fix man page generation

other minor changes

.github/FUNDING.yml

@@ -0,0 +1,12 @@
+# These are supported funding model platforms
+
+github: [drakkan] # Replace with up to 4 GitHub Sponsors-enabled usernames e.g., [user1, user2]
+patreon: # Replace with a single Patreon username
+open_collective: # Replace with a single Open Collective username
+ko_fi: # Replace with a single Ko-fi username
+tidelift: # Replace with a single Tidelift platform-name/package-name e.g., npm/babel
+community_bridge: # Replace with a single Community Bridge project-name e.g., cloud-foundry
+liberapay: # Replace with a single Liberapay username
+issuehunt: # Replace with a single IssueHunt username
+otechie: # Replace with a single Otechie username
+custom: # Replace with up to 4 custom sponsorship URLs e.g., ['link1', 'link2']

.github/workflows/.editorconfig

@@ -0,0 +1,2 @@
+[*.yml]
+indent_size = 2

.github/workflows/development.yml

@@ -0,0 +1,204 @@
+name: CI
+
+on:
+  push:
+    branches: [master]
+  pull_request:
+
+jobs:
+  test-deploy:
+    name: Test and deploy
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        go: [1.15]
+        os: [ubuntu-latest, macos-latest]
+        upload-coverage: [true]
+        include:
+          - go: 1.14
+            os: ubuntu-latest
+            upload-coverage: false
+          - go: 1.15
+            os: windows-latest
+            upload-coverage: false
+
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          fetch-depth: 0
+
+      - name: Set up Go
+        uses: actions/setup-go@v2
+        with:
+          go-version: ${{ matrix.go }}
+
+      - name: Build for Linux/macOS
+        if: startsWith(matrix.os, 'windows-') != true
+        run: go build -ldflags "-s -w -X github.com/drakkan/sftpgo/version.commit=`git describe --always --dirty` -X github.com/drakkan/sftpgo/version.date=`date -u +%FT%TZ`" -o sftpgo
+
+      - name: Build for Windows
+        if: startsWith(matrix.os, 'windows-')
+        run: |
+          $GIT_COMMIT = (git describe --always --dirty) | Out-String
+          $DATE_TIME = ([datetime]::Now.ToUniversalTime().toString("yyyy-MM-ddTHH:mm:ssZ")) | Out-String
+          go build -ldflags "-s -w -X github.com/drakkan/sftpgo/version.commit=$GIT_COMMIT -X github.com/drakkan/sftpgo/version.date=$DATE_TIME" -o sftpgo.exe
+
+      - name: Run test cases using SQLite provider
+        run: go test -v -p 1 -timeout 10m ./... -coverprofile=coverage.txt -covermode=atomic
+
+      - name: Upload coverage to Codecov
+        if: ${{ matrix.upload-coverage }}
+        uses: codecov/codecov-action@v1
+        with:
+          file: ./coverage.txt
+          fail_ci_if_error: false
+
+      - name: Run test cases using bolt provider
+        run: |
+          go test -v -p 1 -timeout 2m ./config -covermode=atomic
+          go test -v -p 1 -timeout 2m ./common -covermode=atomic
+          go test -v -p 1 -timeout 3m ./httpd -covermode=atomic
+          go test -v -p 1 -timeout 8m ./sftpd -covermode=atomic
+          go test -v -p 1 -timeout 2m ./ftpd -covermode=atomic
+          go test -v -p 1 -timeout 2m ./webdavd -covermode=atomic
+        env:
+          SFTPGO_DATA_PROVIDER__DRIVER: bolt
+          SFTPGO_DATA_PROVIDER__NAME: 'sftpgo_bolt.db'
+
+      - name: Run test cases using memory provider
+        run: go test -v -p 1 -timeout 10m ./... -covermode=atomic
+        env:
+          SFTPGO_DATA_PROVIDER__DRIVER: memory
+          SFTPGO_DATA_PROVIDER__NAME: ''
+
+      - name: Prepare build artifact for Linux/macOS
+        if: startsWith(matrix.os, 'windows-') != true
+        run: |
+          mkdir -p output/{bash_completion,zsh_completion}
+          mkdir -p output/examples/rest-api-cli
+          cp sftpgo output/
+          cp sftpgo.json output/
+          cp -r templates output/
+          cp -r static output/
+          cp -r init output/
+          cp examples/rest-api-cli/sftpgo_api_cli output/examples/rest-api-cli/
+          ./sftpgo gen completion bash > output/bash_completion/sftpgo
+          ./sftpgo gen completion zsh > output/zsh_completion/_sftpgo
+          ./sftpgo gen man -d output/man/man1
+          gzip output/man/man1/*
+
+      - name: Prepare build artifact for Windows
+        if: startsWith(matrix.os, 'windows-')
+        run: |
+          mkdir output
+          copy .\sftpgo.exe .\output
+          copy .\sftpgo.json .\output
+          mkdir output\templates
+          xcopy .\templates .\output\templates\ /E
+          mkdir output\static
+          xcopy .\static .\output\static\ /E
+
+      - name: Upload build artifact
+        uses: actions/upload-artifact@v2
+        with:
+          name: sftpgo-${{ matrix.os }}-go${{ matrix.go }}
+          path: output
+
+      - name: Build Linux Packages
+        id: build_linux_pkgs
+        if: ${{ matrix.upload-coverage && startsWith(matrix.os, 'ubuntu-') }}
+        run: |
+          cd pkgs
+          ./build.sh
+          PKG_VERSION=$(cat dist/version)
+          echo "::set-output name=pkg-version::${PKG_VERSION}"
+
+      - name: Upload Debian Package
+        if: ${{ matrix.upload-coverage && startsWith(matrix.os, 'ubuntu-') }}
+        uses: actions/upload-artifact@v2
+        with:
+          name: sftpgo-${{ steps.build_linux_pkgs.outputs.pkg-version }}-x86_64-deb
+          path: pkgs/dist/deb/*
+
+      - name: Upload RPM Package
+        if: ${{ matrix.upload-coverage && startsWith(matrix.os, 'ubuntu-') }}
+        uses: actions/upload-artifact@v2
+        with:
+          name: sftpgo-${{ steps.build_linux_pkgs.outputs.pkg-version }}-x86_64-rpm
+          path: pkgs/dist/rpm/*
+
+  test-postgresql-mysql:
+    name: Test with PostgreSQL/MySQL
+    runs-on: ubuntu-latest
+
+    services:
+      postgres:
+        image: postgres:latest
+        env:
+          POSTGRES_PASSWORD: postgres
+          POSTGRES_DB: sftpgo
+        options: >-
+          --health-cmd pg_isready
+          --health-interval 10s
+          --health-timeout 5s
+          --health-retries 5
+        ports:
+          - 5432:5432
+
+      mariadb:
+        image: mariadb:latest
+        env:
+          MYSQL_ROOT_PASSWORD: mysql
+          MYSQL_DATABASE: sftpgo
+          MYSQL_USER: sftpgo
+          MYSQL_PASSWORD: sftpgo
+        options: >-
+          --health-cmd "mysqladmin status -h 127.0.0.1 -P 3306 -u root -p$MYSQL_ROOT_PASSWORD"
+          --health-interval 10s
+          --health-timeout 5s
+          --health-retries 6
+        ports:
+          - 3307:3306
+
+    steps:
+      - uses: actions/checkout@v2
+
+      - name: Set up Go
+        uses: actions/setup-go@v2
+        with:
+          go-version: 1.15
+
+      - name: Build
+        run: go build -ldflags "-s -w -X github.com/drakkan/sftpgo/version.commit=`git describe --always --dirty` -X github.com/drakkan/sftpgo/version.date=`date -u +%FT%TZ`" -o sftpgo
+
+      - name: Run tests using PostgreSQL provider
+        run: |
+          go test -v -p 1 -timeout 10m ./... -covermode=atomic
+        env:
+          SFTPGO_DATA_PROVIDER__DRIVER: postgresql
+          SFTPGO_DATA_PROVIDER__NAME: sftpgo
+          SFTPGO_DATA_PROVIDER__HOST: localhost
+          SFTPGO_DATA_PROVIDER__PORT: 5432
+          SFTPGO_DATA_PROVIDER__USERNAME: postgres
+          SFTPGO_DATA_PROVIDER__PASSWORD: postgres
+
+      - name: Run tests using MySQL provider
+        run: |
+          go test -v -p 1 -timeout 10m ./... -covermode=atomic
+        env:
+          SFTPGO_DATA_PROVIDER__DRIVER: mysql
+          SFTPGO_DATA_PROVIDER__NAME: sftpgo
+          SFTPGO_DATA_PROVIDER__HOST: localhost
+          SFTPGO_DATA_PROVIDER__PORT: 3307
+          SFTPGO_DATA_PROVIDER__USERNAME: sftpgo
+          SFTPGO_DATA_PROVIDER__PASSWORD: sftpgo
+
+  golangci-lint:
+    name: golangci-lint
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: Run golangci-lint
+        uses: golangci/golangci-lint-action@v2
+        with:
+          version: latest

.github/workflows/docker.yml

@@ -0,0 +1,115 @@
+name: Docker
+
+on:
+  #schedule:
+  #  - cron: '0 4 * * *' # everyday at 4:00 AM UTC
+  push:
+    branches:
+      - master
+    tags:
+      - v*
+  pull_request:
+
+jobs:
+  build:
+    name: Build
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os:
+          - ubuntu-latest
+        docker_pkg: [debian, alpine]
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+
+      - name: Repo metadata
+        id: repo
+        uses: actions/github-script@v3
+        with:
+          script: |
+            const repo = await github.repos.get(context.repo)
+            return repo.data
+
+      - name: Gather image information
+        id: info
+        run: |
+          DOCKER_IMAGE=drakkan/sftpgo
+          VERSION=noop
+          DOCKERFILE=Dockerfile
+          MINOR=""
+          MAJOR=""
+          if [ "${{ github.event_name }}" = "schedule" ]; then
+            VERSION=nightly
+          elif [[ $GITHUB_REF == refs/tags/* ]]; then
+            VERSION=${GITHUB_REF#refs/tags/}
+          elif [[ $GITHUB_REF == refs/heads/* ]]; then
+            VERSION=$(echo ${GITHUB_REF#refs/heads/} | sed -r 's#/+#-#g')
+            if [ "${{ github.event.repository.default_branch }}" = "$VERSION" ]; then
+              VERSION=edge
+            fi
+          elif [[ $GITHUB_REF == refs/pull/* ]]; then
+            VERSION=pr-${{ github.event.number }}
+          fi
+          if [[ $VERSION =~ ^v[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}$ ]]; then
+            MINOR=${VERSION%.*}
+            MAJOR=${MINOR%.*}
+          fi
+          if [[ $DOCKER_PKG == alpine ]]; then
+            VERSION="${VERSION}-alpine"
+            DOCKERFILE=Dockerfile.alpine
+          fi
+          TAGS="${DOCKER_IMAGE}:${VERSION}"
+          if [[ $GITHUB_REF == refs/tags/* ]]; then
+            if [[ $DOCKER_PKG == debian ]]; then
+              if [[ -n $MAJOR && -n $MINOR ]]; then
+                TAGS="$TAGS,${DOCKER_IMAGE}:${MINOR},${DOCKER_IMAGE}:${MAJOR}"
+              fi
+              TAGS="$TAGS,${DOCKER_IMAGE}:latest"
+            else
+              if [[ -n $MAJOR && -n $MINOR ]]; then
+                TAGS="$TAGS,${DOCKER_IMAGE}:${MINOR}-alpine,${DOCKER_IMAGE}:${MAJOR}-alpine"
+              fi
+              TAGS="$TAGS,${DOCKER_IMAGE}:alpine"
+            fi
+          fi
+          echo ::set-output name=dockerfile::${DOCKERFILE}
+          echo ::set-output name=version::${VERSION}
+          echo ::set-output name=tags::${TAGS}
+          echo ::set-output name=created::$(date -u +'%Y-%m-%dT%H:%M:%SZ')
+          echo ::set-output name=sha::${GITHUB_SHA::8}
+        env:
+          DOCKER_PKG: ${{ matrix.docker_pkg }}
+
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v1
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v1
+
+      - name: Login to DockerHub
+        uses: docker/login-action@v1
+        with:
+          username: ${{ secrets.DOCKERHUB_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_TOKEN }}
+        if: github.event_name != 'pull_request'
+
+      - name: Build and push
+        uses: docker/build-push-action@v2
+        with:
+          file: ./${{ steps.info.outputs.dockerfile }}
+          platforms: linux/amd64,linux/arm64
+          push: ${{ github.event_name != 'pull_request' }}
+          tags: ${{ steps.info.outputs.tags }}
+          build-args: |
+            COMMIT_SHA=${{ steps.info.outputs.sha }}
+          labels: |
+            org.opencontainers.image.title=SFTPGo
+            org.opencontainers.image.description=Fully featured and highly configurable SFTP server with optional FTP/S and WebDAV support
+            org.opencontainers.image.url=${{ fromJson(steps.repo.outputs.result).html_url }}
+            org.opencontainers.image.documentation=${{ fromJson(steps.repo.outputs.result).html_url }}/blob/${{ github.sha }}/docker/README.md
+            org.opencontainers.image.source=${{ fromJson(steps.repo.outputs.result).clone_url }}
+            org.opencontainers.image.version=${{ steps.info.outputs.version }}
+            org.opencontainers.image.created=${{ steps.info.outputs.created }}
+            org.opencontainers.image.revision=${{ github.sha }}
+            org.opencontainers.image.licenses=${{ fromJson(steps.repo.outputs.result).license.spdx_id }}

.github/workflows/release.yml

@@ -0,0 +1,291 @@
+name: Release
+
+on:
+  push:
+    tags: 'v*'
+
+env:
+  GO_VERSION: 1.15
+
+jobs:
+  create-release:
+    name: Create
+    runs-on: ubuntu-latest
+    steps:
+      - name: Create Release
+        id: create_release
+        uses: actions/create-release@v1
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          tag_name: ${{ github.ref }}
+          release_name: ${{ github.ref }}
+          draft: false
+          prerelease: false
+
+      - name: Save release upload URL
+        run: echo "${{ steps.create_release.outputs.upload_url }}" > ./upload_url.txt
+        shell: bash
+
+      - name: Store release upload URL
+        uses: actions/upload-artifact@v2
+        with:
+          name: upload_url
+          path: ./upload_url.txt
+
+  release-sources-with-deps:
+    name: Publish sources
+    needs: create-release
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: Set up Go
+        uses: actions/setup-go@v2
+        with:
+          go-version: ${{ env.GO_VERSION }}
+
+      - name: Get SFTPGo version
+        id: get_version
+        run: echo ::set-output name=VERSION::${GITHUB_REF/refs\/tags\//}
+
+      - name: Prepare release
+        run: |
+          go mod vendor
+          echo "${SFTPGO_VERSION}" > VERSION.txt
+          tar cJvf sftpgo_${SFTPGO_VERSION}_src_with_deps.tar.xz *
+        env:
+          SFTPGO_VERSION: ${{ steps.get_version.outputs.VERSION }}
+
+      - name: Download release upload URL
+        uses: actions/download-artifact@v2
+        with:
+          name: upload_url
+
+      - name: Get release upload URL
+        id: upload_url
+        run: |
+          URL=$(cat upload_url.txt)
+          echo "::set-output name=url::${URL}"
+        shell: bash
+
+      - name: Upload Release
+        id: upload-release-asset
+        uses: actions/upload-release-asset@v1
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          upload_url: ${{ steps.upload_url.outputs.url }}
+          asset_path: ./sftpgo_${{ steps.get_version.outputs.VERSION }}_src_with_deps.tar.xz
+          asset_name: sftpgo_${{ steps.get_version.outputs.VERSION }}_src_with_deps.tar.xz
+          asset_content_type: application/x-xz
+
+  publish:
+    name: Publish binary
+    needs: create-release
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [ubuntu-latest, macos-latest, windows-latest]
+
+    steps:
+      - uses: actions/checkout@v2
+      - name: Set up Go
+        uses: actions/setup-go@v2
+        with:
+          go-version: ${{ env.GO_VERSION }}
+
+      - name: Set up Python
+        if: startsWith(matrix.os, 'windows-')
+        uses: actions/setup-python@v2
+        with:
+          python-version: 3.x
+
+      - name: Build for Linux/macOS
+        if: startsWith(matrix.os, 'windows-') != true
+        run: go build -ldflags "-s -w -X github.com/drakkan/sftpgo/version.commit=`git describe --always --dirty` -X github.com/drakkan/sftpgo/version.date=`date -u +%FT%TZ`" -o sftpgo
+
+      - name: Build for Windows
+        if: startsWith(matrix.os, 'windows-')
+        run: |
+          $GIT_COMMIT = (git describe --always --dirty) | Out-String
+          $DATE_TIME = ([datetime]::Now.ToUniversalTime().toString("yyyy-MM-ddTHH:mm:ssZ")) | Out-String
+          go build -ldflags "-s -w -X github.com/drakkan/sftpgo/version.commit=$GIT_COMMIT -X github.com/drakkan/sftpgo/version.date=$DATE_TIME" -o sftpgo.exe
+
+      - name: Initialize data provider
+        run: ./sftpgo initprovider
+        shell: bash
+
+      - name: Get SFTPGo version
+        id: get_version
+        run: echo ::set-output name=VERSION::${GITHUB_REF/refs\/tags\//}
+        shell: bash
+
+      - name: Get OS name
+        id: get_os_name
+        run: |
+          if [ $MATRIX_OS == 'ubuntu-latest' ]
+          then
+            echo ::set-output name=OS::linux
+          elif [ $MATRIX_OS == 'macos-latest' ]
+          then
+            echo ::set-output name=OS::macOS
+          else
+            echo ::set-output name=OS::windows
+          fi
+        shell: bash
+        env:
+          MATRIX_OS: ${{ matrix.os }}
+
+      - name: Build REST API CLI for Windows
+        if: startsWith(matrix.os, 'windows-')
+        run: |
+          python -m pip install --upgrade pip setuptools wheel
+          pip install requests
+          pip install pygments
+          pip install pyinstaller
+          pyinstaller --hidden-import="pkg_resources.py2_warn" --noupx --onefile examples\rest-api-cli\sftpgo_api_cli
+
+      - name: Prepare Release for Linux/macOS
+        if: startsWith(matrix.os, 'windows-') != true
+        run: |
+          mkdir -p output/{init,examples/rest-api-cli,sqlite,bash_completion,zsh_completion}
+          echo "For documentation please take a look here:" > output/README.txt
+          echo "" >> output/README.txt
+          echo "https://github.com/drakkan/sftpgo/blob/${SFTPGO_VERSION}/README.md" >> output/README.txt
+          cp LICENSE output/
+          cp sftpgo output/
+          cp sftpgo.json output/
+          cp sftpgo.db output/sqlite/
+          cp -r static output/
+          cp -r templates output/
+          if [ $OS == 'linux' ]
+          then
+            cp init/sftpgo.service output/init/
+          else
+            cp init/com.github.drakkan.sftpgo.plist output/init/
+          fi
+          ./sftpgo gen completion bash > output/bash_completion/sftpgo
+          ./sftpgo gen completion zsh > output/zsh_completion/_sftpgo
+          ./sftpgo gen man -d output/man/man1
+          gzip output/man/man1/*
+          cp examples/rest-api-cli/sftpgo_api_cli output/examples/rest-api-cli/
+          cd output
+          tar cJvf sftpgo_${SFTPGO_VERSION}_${OS}_x86_64.tar.xz *
+          cd ..
+        env:
+          SFTPGO_VERSION: ${{ steps.get_version.outputs.VERSION }}
+          OS: ${{ steps.get_os_name.outputs.OS }}
+
+      - name: Prepare Linux Packages
+        id: build_linux_pkgs
+        if: ${{ matrix.os == 'ubuntu-latest' }}
+        run: |
+          cd pkgs
+          ./build.sh
+          PKG_VERSION=${SFTPGO_VERSION:1}
+          echo "::set-output name=pkg-version::${PKG_VERSION}"
+        env:
+          SFTPGO_VERSION: ${{ steps.get_version.outputs.VERSION }}
+
+      - name: Prepare Release for Windows
+        if: startsWith(matrix.os, 'windows-')
+        run: |
+          mkdir output
+          copy .\sftpgo.exe .\output
+          copy .\sftpgo.json .\output
+          copy .\sftpgo.db .\output
+          copy .\dist\sftpgo_api_cli.exe .\output
+          copy .\LICENSE .\output\LICENSE.txt
+          mkdir output\templates
+          xcopy .\templates .\output\templates\ /E
+          mkdir output\static
+          xcopy .\static .\output\static\ /E
+          iscc windows-installer\sftpgo.iss
+        env:
+          SFTPGO_ISS_VERSION: ${{ steps.get_version.outputs.VERSION }}
+          SFTPGO_ISS_DOC_URL: https://github.com/drakkan/sftpgo/blob/${{ steps.get_version.outputs.VERSION }}/README.md
+
+      - name: Prepare Portable Release for Windows
+        if: startsWith(matrix.os, 'windows-')
+        run: |
+          mkdir win-portable\examples\rest-api-cli
+          copy .\sftpgo.exe .\win-portable
+          copy .\sftpgo.json .\win-portable
+          copy .\sftpgo.db .\win-portable
+          copy .\dist\sftpgo_api_cli.exe .\win-portable\examples\rest-api-cli
+          copy .\LICENSE .\win-portable\LICENSE.txt
+          mkdir win-portable\templates
+          xcopy .\templates .\win-portable\templates\ /E
+          mkdir win-portable\static
+          xcopy .\static .\win-portable\static\ /E
+          Compress-Archive .\win-portable\* sftpgo_portable_x86_64.zip
+        env:
+          SFTPGO_VERSION: ${{ steps.get_version.outputs.VERSION }}
+          OS: ${{ steps.get_os_name.outputs.OS }}
+
+      - name: Download release upload URL
+        uses: actions/download-artifact@v2
+        with:
+          name: upload_url
+
+      - name: Get release upload URL
+        id: upload_url
+        run: |
+          URL=$(cat upload_url.txt)
+          echo "::set-output name=url::${URL}"
+        shell: bash
+
+      - name: Upload Linux/macOS Release
+        if: startsWith(matrix.os, 'windows-') != true
+        uses: actions/upload-release-asset@v1
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          upload_url: ${{ steps.upload_url.outputs.url }}
+          asset_path: ./output/sftpgo_${{ steps.get_version.outputs.VERSION }}_${{ steps.get_os_name.outputs.OS }}_x86_64.tar.xz
+          asset_name: sftpgo_${{ steps.get_version.outputs.VERSION }}_${{ steps.get_os_name.outputs.OS }}_x86_64.tar.xz
+          asset_content_type: application/x-xz
+
+      - name: Upload Windows Release
+        if: startsWith(matrix.os, 'windows-')
+        uses: actions/upload-release-asset@v1
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          upload_url: ${{ steps.upload_url.outputs.url }}
+          asset_path: ./sftpgo_windows_x86_64.exe
+          asset_name: sftpgo_${{ steps.get_version.outputs.VERSION }}_${{ steps.get_os_name.outputs.OS }}_x86_64.exe
+          asset_content_type: application/x-dosexec
+
+      - name: Upload Portable Windows Release
+        if: startsWith(matrix.os, 'windows-')
+        uses: actions/upload-release-asset@v1
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          upload_url: ${{ steps.upload_url.outputs.url }}
+          asset_path: ./sftpgo_portable_x86_64.zip
+          asset_name: sftpgo_${{ steps.get_version.outputs.VERSION }}_${{ steps.get_os_name.outputs.OS }}_portable_x86_64.zip
+          asset_content_type: application/zip
+
+      - name: Upload Debian Package
+        if: ${{ matrix.os == 'ubuntu-latest' }}
+        uses: actions/upload-release-asset@v1
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          upload_url: ${{ steps.upload_url.outputs.url }}
+          asset_path: ./pkgs/dist/deb/sftpgo_${{ steps.build_linux_pkgs.outputs.pkg-version }}-1_amd64.deb
+          asset_name: sftpgo_${{ steps.build_linux_pkgs.outputs.pkg-version }}-1_amd64.deb
+          asset_content_type: application/vnd.debian.binary-package
+
+      - name: Upload RPM Package
+        if: ${{ matrix.os == 'ubuntu-latest' }}
+        uses: actions/upload-release-asset@v1
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          upload_url: ${{ steps.upload_url.outputs.url }}
+          asset_path: ./pkgs/dist/rpm/sftpgo-${{ steps.build_linux_pkgs.outputs.pkg-version }}-1.x86_64.rpm
+          asset_name: sftpgo-${{ steps.build_linux_pkgs.outputs.pkg-version }}-1.x86_64.rpm
+          asset_content_type: application/x-rpm

.gitignore

@@ -0,0 +1,3 @@
+# compilation output
+sftpgo
+sftpgo.exe

.golangci.yml

@@ -0,0 +1,42 @@
+run:
+  timeout: 5m
+  issues-exit-code: 1
+  tests: true
+
+
+linters-settings:
+  dupl:
+    threshold: 150
+  errcheck:
+    check-type-assertions: false
+    check-blank: false
+  goconst:
+    min-len: 3
+    min-occurrences: 3
+  gocyclo:
+    min-complexity: 15
+  gofmt:
+    simplify: true
+  goimports:
+    local-prefixes: github.com/drakkan/sftpgo
+  maligned:
+    suggest-new: true
+
+linters:
+  enable:
+    - goconst
+    - errcheck
+    - gofmt
+    - goimports
+    - golint
+    - unconvert
+    - unparam
+    - bodyclose
+    - gocyclo
+    - misspell
+    - maligned
+    - whitespace
+    - dupl
+    - scopelint
+    - rowserrcheck
+    - dogsled

.travis.yml

@@ -1,23 +0,0 @@
-language: go
-
-os:
-  - linux
-  - osx
-
-go:
-  - "1.13.x"
-
-env:
-  - GO111MODULE=on
-
-before_script:
-  - sqlite3 sftpgo.db 'CREATE TABLE "users" ("id" integer NOT NULL PRIMARY KEY AUTOINCREMENT, "username" varchar(255) NOT NULL UNIQUE, "password" varchar(255) NULL, "public_keys" text NULL, "home_dir" varchar(255) NOT NULL, "uid" integer NOT NULL, "gid" integer NOT NULL, "max_sessions" integer NOT NULL, "quota_size" bigint NOT NULL, "quota_files" integer NOT NULL, "permissions" text NOT NULL, "used_quota_size" bigint NOT NULL, "used_quota_files" integer NOT NULL, "last_quota_update" bigint NOT NULL, "upload_bandwidth" integer NOT NULL, "download_bandwidth" integer NOT NULL, "expiration_date" bigint NOT NULL, "last_login" bigint NOT NULL, "status" integer NOT NULL, "filters" TEXT NULL);'
-
-install:
-  - go get -v -t ./...
-
-script:
-  - go test -v ./... -coverprofile=coverage.txt -covermode=atomic
-
-after_success:
-  - bash <(curl -s https://codecov.io/bash)

Dockerfile

@@ -0,0 +1,67 @@
+FROM golang:1.15 as builder
+
+ENV GOFLAGS="-mod=readonly"
+
+RUN mkdir -p /workspace
+WORKDIR /workspace
+
+ARG GOPROXY
+
+COPY go.mod go.sum ./
+RUN go mod download
+
+ARG COMMIT_SHA
+
+# This ARG allows to disable some optional features and it might be useful if you build the image yourself.
+# For example you can disable S3 and GCS support like this:
+# --build-arg FEATURES=nos3,nogcs
+ARG FEATURES
+
+COPY . .
+
+RUN set -xe && \
+    export COMMIT_SHA=${COMMIT_SHA:-$(git describe --always --dirty)} && \
+    go build $(if [ -n "${FEATURES}" ]; then echo "-tags ${FEATURES}"; fi) -ldflags "-s -w -X github.com/drakkan/sftpgo/version.commit=${COMMIT_SHA} -X github.com/drakkan/sftpgo/version.date=`date -u +%FT%TZ`" -v -o sftpgo
+
+FROM debian:buster-slim
+
+RUN apt-get update && apt-get install --no-install-recommends -y ca-certificates mime-support && apt-get clean
+
+SHELL ["/bin/bash", "-c"]
+
+RUN mkdir -p /etc/sftpgo /var/lib/sftpgo /usr/share/sftpgo /srv/sftpgo
+
+RUN groupadd --system -g 1000 sftpgo && \
+    useradd --system --gid sftpgo --no-create-home \
+    --home-dir /var/lib/sftpgo --shell /usr/sbin/nologin \
+    --comment "SFTPGo user" --uid 1000 sftpgo
+
+# Install some optional packages used by SFTPGo features
+RUN apt-get update && apt-get install --no-install-recommends -y git rsync && apt-get clean
+
+COPY --from=builder /workspace/sftpgo.json /etc/sftpgo/sftpgo.json
+COPY --from=builder /workspace/templates /usr/share/sftpgo/templates
+COPY --from=builder /workspace/static /usr/share/sftpgo/static
+COPY --from=builder /workspace/sftpgo /usr/local/bin/
+
+# Log to the stdout so the logs will be available using docker logs
+ENV SFTPGO_LOG_FILE_PATH=""
+# templates and static paths are inside the container
+ENV SFTPGO_HTTPD__TEMPLATES_PATH=/usr/share/sftpgo/templates
+ENV SFTPGO_HTTPD__STATIC_FILES_PATH=/usr/share/sftpgo/static
+
+# Modify the default configuration file
+RUN sed -i "s|\"users_base_dir\": \"\",|\"users_base_dir\": \"/srv/sftpgo/data\",|" /etc/sftpgo/sftpgo.json && \
+    sed -i "s|\"backups\"|\"/srv/sftpgo/backups\"|" /etc/sftpgo/sftpgo.json && \
+    sed -i "s|\"bind_address\": \"127.0.0.1\",|\"bind_address\": \"\",|" /etc/sftpgo/sftpgo.json
+
+RUN chown -R sftpgo:sftpgo /etc/sftpgo && chown sftpgo:sftpgo /var/lib/sftpgo /srv/sftpgo && \
+    chmod 640 /etc/sftpgo/sftpgo.json && \
+    chmod 750 /etc/sftpgo /var/lib/sftpgo /srv/sftpgo
+
+WORKDIR /var/lib/sftpgo
+USER sftpgo
+
+VOLUME [ "/var/lib/sftpgo", "/srv/sftpgo" ]
+
+CMD sftpgo serve

Dockerfile.alpine

@@ -0,0 +1,72 @@
+FROM golang:1.15-alpine AS builder
+
+ENV GOFLAGS="-mod=readonly"
+
+RUN apk add --update --no-cache bash ca-certificates curl git gcc g++
+
+RUN mkdir -p /workspace
+WORKDIR /workspace
+
+ARG GOPROXY
+
+COPY go.mod go.sum ./
+RUN go mod download
+
+ARG COMMIT_SHA
+
+# This ARG allows to disable some optional features and it might be useful if you build the image yourself.
+# For example you can disable S3 and GCS support like this:
+# --build-arg FEATURES=nos3,nogcs
+ARG FEATURES
+
+COPY . .
+
+RUN set -xe && \
+    export COMMIT_SHA=${COMMIT_SHA:-$(git describe --always --dirty)} && \
+    go build $(if [ -n "${FEATURES}" ]; then echo "-tags ${FEATURES}"; fi) -ldflags "-s -w -X github.com/drakkan/sftpgo/version.commit=${COMMIT_SHA} -X github.com/drakkan/sftpgo/version.date=`date -u +%FT%TZ`" -v -o sftpgo
+
+
+FROM alpine:3.12
+
+RUN apk add --update --no-cache ca-certificates tzdata bash mailcap
+
+SHELL ["/bin/bash", "-c"]
+
+# set up nsswitch.conf for Go's "netgo" implementation
+# https://github.com/gliderlabs/docker-alpine/issues/367#issuecomment-424546457
+RUN test ! -e /etc/nsswitch.conf && echo 'hosts: files dns' > /etc/nsswitch.conf
+
+RUN mkdir -p /etc/sftpgo /var/lib/sftpgo /usr/share/sftpgo /srv/sftpgo
+
+RUN addgroup -g 1000 -S sftpgo && \
+    adduser -u 1000 -h /var/lib/sftpgo -s /sbin/nologin -G sftpgo -S -D -H sftpgo
+
+# Install some optional packages used by SFTPGo features
+RUN apk add --update --no-cache rsync git
+
+COPY --from=builder /workspace/sftpgo.json /etc/sftpgo/sftpgo.json
+COPY --from=builder /workspace/templates /usr/share/sftpgo/templates
+COPY --from=builder /workspace/static /usr/share/sftpgo/static
+COPY --from=builder /workspace/sftpgo /usr/local/bin/
+
+# Log to the stdout so the logs will be available using docker logs
+ENV SFTPGO_LOG_FILE_PATH=""
+# templates and static paths are inside the container
+ENV SFTPGO_HTTPD__TEMPLATES_PATH=/usr/share/sftpgo/templates
+ENV SFTPGO_HTTPD__STATIC_FILES_PATH=/usr/share/sftpgo/static
+
+# Modify the default configuration file
+RUN sed -i "s|\"users_base_dir\": \"\",|\"users_base_dir\": \"/srv/sftpgo/data\",|" /etc/sftpgo/sftpgo.json && \
+    sed -i "s|\"backups\"|\"/srv/sftpgo/backups\"|" /etc/sftpgo/sftpgo.json && \
+    sed -i "s|\"bind_address\": \"127.0.0.1\",|\"bind_address\": \"\",|" /etc/sftpgo/sftpgo.json
+
+RUN chown -R sftpgo:sftpgo /etc/sftpgo && chown sftpgo:sftpgo /var/lib/sftpgo /srv/sftpgo && \
+    chmod 640 /etc/sftpgo/sftpgo.json && \
+    chmod 750 /etc/sftpgo /var/lib/sftpgo /srv/sftpgo
+
+WORKDIR /var/lib/sftpgo
+USER sftpgo
+
+VOLUME [ "/var/lib/sftpgo", "/srv/sftpgo" ]
+
+CMD sftpgo serve

README.md

@@ -1,644 +1,212 @@
 # SFTPGo
-[![Build Status](https://travis-ci.org/drakkan/sftpgo.svg?branch=master)](https://travis-ci.org/drakkan/sftpgo) [![Code Coverage](https://codecov.io/gh/drakkan/sftpgo/branch/master/graph/badge.svg)](https://codecov.io/gh/drakkan/sftpgo/branch/master) [![Go Report Card](https://goreportcard.com/badge/github.com/drakkan/sftpgo)](https://goreportcard.com/report/github.com/drakkan/sftpgo) [![License: GPL v3](https://img.shields.io/badge/License-GPLv3-blue.svg)](https://www.gnu.org/licenses/gpl-3.0) [![Mentioned in Awesome Go](https://awesome.re/mentioned-badge.svg)](https://github.com/avelino/awesome-go)
 
-Full featured and highly configurable SFTP server
+![CI Status](https://github.com/drakkan/sftpgo/workflows/CI/badge.svg?branch=master&event=push)
+[![Code Coverage](https://codecov.io/gh/drakkan/sftpgo/branch/master/graph/badge.svg)](https://codecov.io/gh/drakkan/sftpgo/branch/master)
+[![Go Report Card](https://goreportcard.com/badge/github.com/drakkan/sftpgo)](https://goreportcard.com/report/github.com/drakkan/sftpgo)
+[![License: GPL v3](https://img.shields.io/badge/License-GPLv3-blue.svg)](https://www.gnu.org/licenses/gpl-3.0)
+[![Mentioned in Awesome Go](https://awesome.re/mentioned-badge.svg)](https://github.com/avelino/awesome-go)
+
+Fully featured and highly configurable SFTP server with optional FTP/S and WebDAV support, written in Go.
+It can serve local filesystem, S3 or Google Cloud Storage.
 
 ## Features
 
-- Each account is chrooted to his Home Dir.
-- SFTP accounts are virtual accounts stored in a "data provider".
-- SQLite, MySQL, PostgreSQL, bbolt (key/value store in pure Go) and in memory data providers are supported.
+- SFTPGo uses virtual accounts stored inside a "data provider".
+- SQLite, MySQL, PostgreSQL, bbolt (key/value store in pure Go) and in-memory data providers are supported.
+- Each account is chrooted to its home directory.
 - Public key and password authentication. Multiple public keys per user are supported.
-- Custom authentication using external programs is supported.
+- SSH user [certificate authentication](https://cvsweb.openbsd.org/src/usr.bin/ssh/PROTOCOL.certkeys?rev=1.8).
+- Keyboard interactive authentication. You can easily setup a customizable multi-factor authentication.
+- Partial authentication. You can configure multi-step authentication requiring, for example, the user password after successful public key authentication.
+- Per user authentication methods. You can configure the allowed authentication methods for each user.
+- Custom authentication via external programs/HTTP API is supported.
+- Dynamic user modification before login via external programs/HTTP API is supported.
 - Quota support: accounts can have individual quota expressed as max total size and/or max number of files.
 - Bandwidth throttling is supported, with distinct settings for upload and download.
 - Per user maximum concurrent sessions.
-- Per user and per directory permissions: list directories content, upload, overwrite, download, delete, rename, create directories, create symlinks, changing owner/group and mode, changing access and modification times can be enabled or disabled.
-- Per user files/folders ownership: you can map all the users to the system account that runs SFTPGo (all platforms are supported) or you can run SFTPGo as root user and map each user or group of users to a different system account (*NIX only).
+- Per user and per directory permission management: list directory contents, upload, overwrite, download, delete, rename, create directories, create symlinks, change owner/group and mode, change access and modification times.
+- Per user files/folders ownership mapping: you can map all the users to the system account that runs SFTPGo (all platforms are supported) or you can run SFTPGo as root user and map each user or group of users to a different system account (\*NIX only).
 - Per user IP filters are supported: login can be restricted to specific ranges of IP addresses or to a specific IP address.
-- Configurable custom commands and/or HTTP notifications on file upload, download, delete, rename, on SSH commands and on user add, update and delete.
+- Per user and per directory file extensions filters are supported: files can be allowed or denied based on their extensions.
+- Virtual folders are supported: directories outside the user home directory can be exposed as virtual folders.
+- Configurable custom commands and/or HTTP notifications on file upload, download, pre-delete, delete, rename, on SSH commands and on user add, update and delete.
 - Automatically terminating idle connections.
 - Atomic uploads are configurable.
 - Support for Git repositories over SSH.
 - SCP and rsync are supported.
-- Prometheus metrics are exposed.
-- REST API for users management, backup, restore and real time reports of the active connections with possibility of forcibly closing a connection.
-- Web based interface to easily manage users and connections.
-- Easy migration from Linux system user accounts.
-- Portable mode: a convenient way to share a single directory on demand.
-- Configuration is a your choice: JSON, TOML, YAML, HCL, envfile are supported.
-- Log files are accurate and they are saved in the easily parsable JSON format.
+- FTP/S is supported. You can configure the FTP service to require TLS for both control and data connections.
+- [WebDAV](./docs/webdav.md) is supported.
+- Support for serving local filesystem, S3 Compatible Object Storage and Google Cloud Storage over SFTP/SCP/FTP/WebDAV.
+- Per user protocols restrictions. You can configure the allowed protocols (SSH/FTP/WebDAV) for each user.
+- [Prometheus metrics](./docs/metrics.md) are exposed.
+- Support for HAProxy PROXY protocol: you can proxy and/or load balance the SFTP/SCP/FTP/WebDAV service without losing the information about the client's address.
+- [REST API](./docs/rest-api.md) for users and folders management, backup, restore and real time reports of the active connections with possibility of forcibly closing a connection.
+- [Web based administration interface](./docs/web-admin.md) to easily manage users, folders and connections.
+- Easy [migration](./examples/rest-api-cli#convert-users-from-other-stores) from Linux system user accounts.
+- [Portable mode](./docs/portable-mode.md): a convenient way to share a single directory on demand.
+- Performance analysis using built-in [profiler](./docs/profiling.md).
+- Configuration format is at your choice: JSON, TOML, YAML, HCL, envfile are supported.
+- Log files are accurate and they are saved in the easily parsable JSON format ([more information](./docs/logs.md)).
 
 ## Platforms
 
-SFTPGo is developed and tested on Linux. After each commit the code is automatically built and tested on Linux and macOS using Travis CI.
-Regularly the test cases are manually executed and pass on Windows. Other UNIX variants such as *BSD should work too.
+SFTPGo is developed and tested on Linux. After each commit, the code is automatically built and tested on Linux, macOS and Windows using a [GitHub Action](./.github/workflows/development.yml). The test cases are regularly manually executed and passed on FreeBSD. Other *BSD variants should work too.
 
 ## Requirements
 
 - Go 1.13 or higher as build only dependency.
-- A suitable SQL server or key/value store to use as data provider: PostreSQL 9.4+ or MySQL 5.6+ or SQLite 3.x or bbolt 1.3.x
+- A suitable SQL server to use as data provider: PostgreSQL 9.4+ or MySQL 5.6+ or SQLite 3.x.
+- The SQL server is optional: you can choose to use an embedded bolt database as key/value store or an in memory data provider.
 
 ## Installation
 
-Binary releases for Linux, macOS and Windows are available, please visit the [releases](https://github.com/drakkan/sftpgo/releases "releases") page.
+Binary releases for Linux, macOS, and Windows are available. Please visit the [releases](https://github.com/drakkan/sftpgo/releases "releases") page.
 
-Sample Dockerfiles for [Debian](https://www.debian.org "Debian") and [Alpine](https://alpinelinux.org "Alpine") are available inside the source tree [docker](./docker "docker") directory.
+Official Docker images are available. Documentation is [here](./docker/README.md).
 
 Some Linux distro packages are available:
 
 - For Arch Linux via AUR:
-  - [sftpgo](https://aur.archlinux.org/packages/sftpgo/). This package follow stable releases. It requires `git`, `gcc` and `go` to build.
-  - [sftpgo-bin](https://aur.archlinux.org/packages/sftpgo-bin/). This package follow stable releases downloading the prebuilt linux binary from GitHub. It does not require `git`, `gcc` and `go` to build.
-  - [sftpgo-git](https://aur.archlinux.org/packages/sftpgo-git/). This package build and install the latest git master. It requires `git`, `gcc` and `go` to build.
+  - [sftpgo](https://aur.archlinux.org/packages/sftpgo/). This package follows stable releases. It requires `git`, `gcc` and `go` to build.
+  - [sftpgo-bin](https://aur.archlinux.org/packages/sftpgo-bin/). This package follows stable releases downloading the prebuilt linux binary from GitHub. It does not require `git`, `gcc` and `go` to build.
+  - [sftpgo-git](https://aur.archlinux.org/packages/sftpgo-git/). This package builds and installs the latest git master. It requires `git`, `gcc` and `go` to build.
+- Deb and RPM packages are built after each commit and for each release.
+- For Ubuntu a PPA is available [here](https://launchpad.net/~sftpgo/+archive/ubuntu/sftpgo).
 
-Alternately you can install the package to your [$GOPATH](https://github.com/golang/go/wiki/GOPATH "GOPATH") with the [go tool](https://golang.org/cmd/go/ "go command") from shell:
+You can easily test new features selecting a commit from the [Actions](https://github.com/drakkan/sftpgo/actions) page and downloading the matching build artifacts for Linux, macOS or Windows. GitHub stores artifacts for 90 days.
 
-```
-$ go get -u github.com/drakkan/sftpgo
-```
-
-Make sure [Git](https://git-scm.com/downloads) is installed on your machine and in your system's `PATH`.
-
-SFTPGo depends on [go-sqlite3](https://github.com/mattn/go-sqlite3) that is a CGO package and so it requires a `C` compiler at build time.
-On Linux and macOS a compiler is easy to install or already installed, on Windows you need to download [MinGW-w64](https://sourceforge.net/projects/mingw-w64/files/) and build SFTPGo from its command prompt.
-
-The compiler is a build time only dependency, it is not not required at runtime.
-
-If you don't need SQLite, you can also get/build SFTPGo setting the environment variable `GCO_ENABLED` to 0, this way SQLite support will be disabled but PostgreSQL, MySQL, bbolt and memory data providers will work and you don't need a `C` compiler for building.
-
-Version info, such as git commit and build date, can be embedded setting the following string variables at build time:
-
-- `github.com/drakkan/sftpgo/utils.commit`
-- `github.com/drakkan/sftpgo/utils.date`
-
-For example you can build using the following command:
-
-```
-go build -i -ldflags "-s -w -X github.com/drakkan/sftpgo/utils.commit=`git describe --always --dirty` -X github.com/drakkan/sftpgo/utils.date=`date -u +%FT%TZ`" -o sftpgo
-```
-
-and you will get a version that includes git commit and build date like this one:
-
-```
-sftpgo -v
-SFTPGo version: 0.9.0-dev-90607d4-dirty-2019-08-08T19:28:36Z
-```
-
-For Linux, a `systemd` sample [service](./init/sftpgo.service "systemd service") can be found inside the source tree.
-
-For macOS a `launchd` sample [service](./init/com.github.drakkan.sftpgo.plist "launchd plist") can be found inside the source tree. The `launchd` plist assumes that `sftpgo` has `/usr/local/opt/sftpgo` as base directory.
-
-On Windows you can run `SFTPGo` as Windows Service, please read the "Configuration" section below for more details.
+Alternately, you can [build from source](./docs/build-from-source.md).
 
 ## Configuration
 
-The `sftpgo` executable can be used this way:
+A full explanation of all configuration methods can be found [here](./docs/full-configuration.md).
 
-```
-Usage:
-  sftpgo [command]
+Please make sure to [initialize the data provider](#data-provider-initialization) before running the daemon!
 
-Available Commands:
-  help        Help about any command
-  portable    Serve a single directory
-  serve       Start the SFTP Server
+To start SFTPGo with the default settings, simply run:
 
-Flags:
-  -h, --help      help for sftpgo
-  -v, --version
-
- Use "sftpgo [command] --help" for more information about a command
-```
-
-The `serve` subcommand supports the following flags:
-
-- `--config-dir` string. Location of the config dir. This directory should contain the `sftpgo` configuration file and is used as the base for files with a relative path (eg. the private keys for the SFTP server, the SQLite or bblot database if you use SQLite or bbolt as data provider). The default value is "." or the value of `SFTPGO_CONFIG_DIR` environment variable.
-- `--config-file` string. Name of the configuration file. It must be the name of a file stored in config-dir not the absolute path to the configuration file. The specified file name must have no extension we automatically load JSON, YAML, TOML, HCL and Java properties. The default value is "sftpgo" (and therefore `sftpgo.json`, `sftpgo.yaml` and so on are searched) or the value of `SFTPGO_CONFIG_FILE` environment variable.
-- `--log-compress` boolean. Determine if the rotated log files should be compressed using gzip. Default `false` or the value of `SFTPGO_LOG_COMPRESS` environment variable (1 or `true`, 0 or `false`). It is unused if `log-file-path` is empty.
-- `--log-file-path` string. Location for the log file, default "sftpgo.log" or the value of `SFTPGO_LOG_FILE_PATH` environment variable. Leave empty to write logs to the standard error.
-- `--log-max-age` int. Maximum number of days to retain old log files. Default 28 or the value of `SFTPGO_LOG_MAX_AGE` environment variable. It is unused if `log-file-path` is empty.
-- `--log-max-backups` int. Maximum number of old log files to retain. Default 5 or the value of `SFTPGO_LOG_MAX_BACKUPS` environment variable. It is unused if `log-file-path` is empty.
-- `--log-max-size` int. Maximum size in megabytes of the log file before it gets rotated. Default 10 or the value of `SFTPGO_LOG_MAX_SIZE` environment variable. It is unused if `log-file-path` is empty.
-- `--log-verbose` boolean. Enable verbose logs. Default `true` or the value of `SFTPGO_LOG_VERBOSE` environment variable (1 or `true`, 0 or `false`).
-
-If you don't configure any private host keys, the daemon will use `id_rsa` in the configuration directory. If that file doesn't exist, the daemon will attempt to autogenerate it (if the user that executes SFTPGo has write access to the config-dir). The server supports any private key format supported by [`crypto/ssh`](https://github.com/golang/crypto/blob/master/ssh/keys.go#L32).
-
-Before starting `sftpgo` a dataprovider must be configured.
-
-SQL scripts to create the required database structure can be found inside the source tree [sql](./sql "sql") directory. The SQL scripts filename is, by convention, the date as `YYYYMMDD` and the suffix `.sql`. You need to apply all the SQL scripts for your database ordered by name, for example `20190828.sql` must be applied before `20191112.sql` and so on.
-
-The `sftpgo` configuration file contains the following sections:
-
-- **"sftpd"**, the configuration for the SFTP server
-    - `bind_port`, integer. The port used for serving SFTP requests. Default: 2022
-    - `bind_address`, string. Leave blank to listen on all available network interfaces. Default: ""
-    - `idle_timeout`, integer. Time in minutes after which an idle client will be disconnected. 0 menas disabled. Default: 15
-    - `max_auth_tries` integer. Maximum number of authentication attempts permitted per connection. If set to a negative number, the number of attempts are unlimited. If set to zero, the number of attempts are limited to 6.
-    - `umask`, string. Umask for the new files and directories. This setting has no effect on Windows. Default: "0022"
-    - `banner`, string. Identification string used by the server. Leave empty to use the default banner. Default "SFTPGo_version"
-    - `upload_mode` integer. 0 means standard, the files are uploaded directly to the requested path. 1 means atomic: files are uploaded to a temporary path and renamed to the requested path when the client ends the upload. Atomic mode avoids problems such as a web server that serves partial files when the files are being uploaded. In atomic mode if there is an upload error the temporary file is deleted and so the requested upload path will not contain a partial file. 2 means atomic with resume support: as atomic but if there is an upload error the temporary file is renamed to the requested path and not deleted, this way a client can reconnect and resume the upload.
-    - `actions`, struct. It contains the command to execute and/or the HTTP URL to notify and the trigger conditions. See the "Custom Actions" paragraph for more details
-        - `execute_on`, list of strings. Valid values are `download`, `upload`, `delete`, `rename`, `ssh_cmd`. Leave empty to disable actions.
-        - `command`, string. Absolute path to the command to execute. Leave empty to disable.
-        - `http_notification_url`, a valid URL. An HTTP GET request will be executed to this URL. Leave empty to disable.
-    - `keys`, struct array. It contains the daemon's private keys. If empty or missing the daemon will search or try to generate `id_rsa` in the configuration directory.
-        - `private_key`, path to the private key file. It can be a path relative to the config dir or an absolute one.
-    - `enable_scp`, boolean. Default disabled. Set to `true` to enable the experimental SCP support. This setting is deprecated and will be removed in future versions, please add `scp` to the `enabled_ssh_commands` list to enable it
-    - `kex_algorithms`, list of strings. Available KEX (Key Exchange) algorithms in preference order. Leave empty to use default values. The supported values can be found here: [`crypto/ssh`](https://github.com/golang/crypto/blob/master/ssh/common.go#L46 "Supported kex algos")
-    - `ciphers`, list of strings. Allowed ciphers. Leave empty to use default values. The supported values can be found here: [`crypto/ssh`](https://github.com/golang/crypto/blob/master/ssh/common.go#L28 "Supported ciphers")
-    - `macs`, list of strings. available MAC (message authentication code) algorithms in preference order. Leave empty to use default values. The supported values can be found here: [`crypto/ssh`](https://github.com/golang/crypto/blob/master/ssh/common.go#L84 "Supported MACs")
-    - `login_banner_file`, path to the login banner file. The contents of the specified file, if any, are sent to the remote user before authentication is allowed. It can be a path relative to the config dir or an absolute one. Leave empty to send no login banner
-    - `setstat_mode`, integer. 0 means "normal mode": requests for changing permissions, owner/group and access/modification times are executed. 1 means "ignore mode": requests for changing permissions, owner/group and access/modification times are silently ignored.
-    - `enabled_ssh_commands`, list of enabled SSH commands. These SSH commands are enabled by default: `md5sum`, `sha1sum`, `cd`, `pwd`. `*` enables all supported commands. Some commands are implemented directly inside SFTPGo, while for other commands we use system commands that need to be installed and in your system's `PATH`. For system commands we have no direct control on file creation/deletion and so quota check is suboptimal: if quota is enabled, the number of files is checked at the command begin and not while new files are created. The allowed size is calculated as the difference between the max quota and the used one and it is checked against the bytes transferred via SSH. The command is aborted if it uploads more bytes than the remaining allowed size calculated at the command start. Anyway we see the bytes that the remote command send to the local command via SSH, these bytes contain both protocol commands and files and so the size of the files is different from the size trasferred via SSH: for example a command can send compressed files or a protocol command (few bytes) could delete a big file. To mitigate this issue quotas are recalculated at the command end with a full home directory scan, this could be heavy for big directories. If you need system commands and quotas you could consider to disable quota restrictions and periodically update quota usage yourself using the REST API. We support the following SSH commands:
-      - `scp`, SCP is an experimental feature, we have our own SCP implementation since we can't rely on "scp" system command to proper handle quotas and user's home dir restrictions. The SCP protocol is quite simple but there is no official docs about it, so we need more testing and feedbacks before enabling it by default. We may not handle some borderline cases or have sneaky bugs. Please do accurate tests yourself before enabling SCP and let us known if something does not work as expected for your use cases. SCP between two remote hosts is supported using the `-3` scp option.
-      - `md5sum`, `sha1sum`, `sha256sum`, `sha384sum`, `sha512sum`. Useful to check message digests for uploaded files. These commands are implemented inside SFTPGo so they work even if the matching system commands are not available, for example on Windows.
-      - `cd`, `pwd`. Some SFTP clients does not support the SFTP SSH_FXP_REALPATH packet type and so they use `cd` and `pwd` SSH commands to get the initial directory. Currently `cd` do nothing and `pwd` always returns the `/` path.
-      - `git-receive-pack`, `git-upload-pack`, `git-upload-archive`. These commands enable support for Git repositories over SSH, they need to be installed and in your system's `PATH`.
-      - `rsync`. The `rsync` command need to be installed and in your system's `PATH`. We cannot avoid that rsync create symlinks so if the user has the permission to create symlinks we add the option `--safe-links` to the received rsync command if it is not already set. This should prevent to create symlinks that point outside the home dir. If the user cannot create symlinks we add the option `--munge-links`, if it is not already set. This should make symlinks unusable (but manually recoverable)
-- **"data_provider"**, the configuration for the data provider
-    - `driver`, string. Supported drivers are `sqlite`, `mysql`, `postgresql`, `bolt`, `memory`
-    - `name`, string. Database name. For driver `sqlite` this can be the database name relative to the config dir or the absolute path to the SQLite database.
-    - `host`, string. Database host. Leave empty for drivers `sqlite`, `bolt` and `memory`
-    - `port`, integer. Database port. Leave empty for drivers `sqlite`, `bolt` and `memory`
-    - `username`, string. Database user. Leave empty for drivers `sqlite`, `bolt` and `memory`
-    - `password`, string. Database password. Leave empty for drivers `sqlite`, `bolt` and `memory`
-    - `sslmode`, integer. Used for drivers `mysql` and `postgresql`. 0 disable SSL/TLS connections, 1 require ssl, 2 set ssl mode to `verify-ca` for driver `postgresql` and `skip-verify` for driver `mysql`, 3 set ssl mode to `verify-full` for driver `postgresql` and `preferred` for driver `mysql`
-    - `connectionstring`, string. Provide a custom database connection string. If not empty this connection string will be used instead of build one using the previous parameters. Leave empty for drivers `bolt` and `memory`
-    - `users_table`, string. Database table for SFTP users
-    - `manage_users`, integer. Set to 0 to disable users management, 1 to enable
-    - `track_quota`, integer. Set the preferred mode to track users quota between the following choices:
-        - 0, disable quota tracking. REST API to scan user dir and update quota will do nothing
-        - 1, quota is updated each time a user upload or delete a file even if the user has no quota restrictions
-        - 2, quota is updated each time a user upload or delete a file but only for users with quota restrictions. With this configuration the "quota scan" REST API can still be used to periodically update space usage for users without quota restrictions
-    - `pool_size`, integer. Sets the maximum number of open connections for `mysql` and `postgresql` driver. Default 0 (unlimited)
-    - `users_base_dir`, string. Users' default base directory. If no home dir is defined while adding a new user, and this value is a valid absolute path, then the user home dir will be automatically defined as the path obtained joining the base dir and the username
-    - `actions`, struct. It contains the command to execute and/or the HTTP URL to notify and the trigger conditions. See the "Custom Actions" paragraph for more details
-        - `execute_on`, list of strings. Valid values are `add`, `update`, `delete`. `update` action will not be fired for internal updates such as the last login or the user quota fields.
-        - `command`, string. Absolute path to the command to execute. Leave empty to disable.
-        - `http_notification_url`, a valid URL. Leave empty to disable.
-    - `external_auth_program`, string. Absolute path to an external program to use for users authentication. See the "External Authentication" paragraph for more details.
-    - `external_auth_scope`, integer. 0 means all supported authetication scopes (passwords and public keys). 1 means passwords only. 2 means public keys only
-- **"httpd"**, the configuration for the HTTP server used to serve REST API
-    - `bind_port`, integer. The port used for serving HTTP requests. Set to 0 to disable HTTP server. Default: 8080
-    - `bind_address`, string. Leave blank to listen on all available network interfaces. Default: "127.0.0.1"
-    - `templates_path`, string. Path to the HTML web templates. This can be an absolute path or a path relative to the config dir
-    - `static_files_path`, string. Path to the static files for the web interface. This can be an absolute path or a path relative to the config dir
-    - `backups_path`, string. Path to the backup directory. This can be an absolute path or a path relative to the config dir. We don't allow backups in arbitrary paths for security reasons
-
-Here is a full example showing the default config in JSON format:
-
-```json
-{
-  "sftpd": {
-    "bind_port": 2022,
-    "bind_address": "",
-    "idle_timeout": 15,
-    "max_auth_tries": 0,
-    "umask": "0022",
-    "banner": "",
-    "upload_mode": 0,
-    "actions": {
-      "execute_on": [],
-      "command": "",
-      "http_notification_url": ""
-    },
-    "keys": [],
-    "enable_scp": false,
-    "kex_algorithms": [],
-    "ciphers": [],
-    "macs": [],
-    "login_banner_file": "",
-    "setstat_mode": 0,
-    "enabled_ssh_commands": ["md5sum", "sha1sum", "cd", "pwd"]
-  },
-  "data_provider": {
-    "driver": "sqlite",
-    "name": "sftpgo.db",
-    "host": "",
-    "port": 5432,
-    "username": "",
-    "password": "",
-    "sslmode": 0,
-    "connection_string": "",
-    "users_table": "users",
-    "manage_users": 1,
-    "track_quota": 2,
-    "pool_size": 0,
-    "users_base_dir": "",
-    "actions": {
-      "execute_on": [],
-      "command": "",
-      "http_notification_url": ""
-    },
-    "external_auth_program": "",
-    "external_auth_scope": 0
-  },
-  "httpd": {
-    "bind_port": 8080,
-    "bind_address": "127.0.0.1",
-    "templates_path": "templates",
-    "static_files_path": "static",
-    "backups_path": "backups"
-  }
-}
-```
-
-If you want to use a private key that use an algorithm different from RSA or more than one private key then replace the empty `keys` array with something like this:
-
-```json
-"keys": [
-  {
-    "private_key": "id_rsa"
-  },
-  {
-    "private_key": "id_ecdsa"
-  }
-]
-```
-
-The configuration can be read from JSON, TOML, YAML, HCL, envfile and Java properties config files, if your `config-file` flag is set to `sftpgo` (default value) you need to create a configuration file called `sftpgo.json` or `sftpgo.yaml` and so on inside `config-dir`.
-
-You can also override all the available configuration options using environment variables, sftpgo will check for environment variables with a name matching the key uppercased and prefixed with the `SFTPGO_`. You need to use `__` to traverse a struct.
-
-Let's see some examples:
-
-- To set sftpd `bind_port` you need to define the env var `SFTPGO_SFTPD__BIND_PORT`
-- To set the `execute_on` actions you need to define the env var `SFTPGO_SFTPD__ACTIONS__EXECUTE_ON` for example `SFTPGO_SFTPD__ACTIONS__EXECUTE_ON=upload,download`
-
-Please note that to override configuration options with environment variables a configuration file containing the options to override is required. You can, for example, deploy the default configuration file and then override the options you need to customize using environment variables.
-
-To start the SFTP Server with the default values for the command line flags simply use:
-
-```
+```bash
 sftpgo serve
 ```
 
-On Windows you can register `SFTPGo` as Windows Service, take a look at the CLI usage to learn how:
+Check out [this documentation](./docs/service.md) if you want to run SFTPGo as a service.
 
-```
-sftpgo.exe service --help
-Install, Uninstall, Start, Stop and retrieve status for SFTPGo Windows Service
+### Data provider initialization and update
 
-Usage:
-  sftpgo service [command]
+Before starting the SFTPGo server please ensure that the configured data provider is properly initialized/updated.
 
-Available Commands:
-  install     Install SFTPGo as Windows Service
-  start       Start SFTPGo Windows Service
-  status      Retrieve the status for the SFTPGo Windows Service
-  stop        Stop SFTPGo Windows Service
-  uninstall   Uninstall SFTPGo Windows Service
+SQL based data providers (SQLite, MySQL, PostgreSQL) require the creation of a database containing the required tables. Memory and bolt data providers do not require an initialization but they could require an update to the existing data after upgrading SFTPGo.
 
-Flags:
-  -h, --help   help for service
+For PostgreSQL and MySQL providers, you need to create the configured database.
 
-Use "sftpgo service [command] --help" for more information about a command.
+SFTPGo will attempt to automatically detect if the data provider is initialized/updated and if not, will attempt to initialize/ update it on startup as needed.
+
+Alternately, you can create/update the required data provider structures yourself using the `initprovider` command.
+
+For example, you can simply execute the following command from the configuration directory:
+
+```bash
+sftpgo initprovider
 ```
 
-`install` subcommand accepts the same flags valid for `serve`.
+Take a look at the CLI usage to learn how to specify a different configuration file:
 
-After installing as Windows Service please remember to allow network access to the SFTPGo executable using something like this:
-
-```
-netsh advfirewall firewall add rule name="SFTPGo Service" dir=in action=allow program="C:\Program Files\SFTPGo\sftpgo.exe"
+```bash
+sftpgo initprovider --help
 ```
 
-or through the Windows Firewall GUI.
+You can disable automatic data provider checks/updates at startup by setting the `update_mode` configuration key to `1`.
 
-## External Authentication
+## Users and folders management
 
-Custom authentication methods can easily be added. SFTPGo supports external authentication modules, and writing a new backend can be as simple as a few lines of shell script.
+After starting SFTPGo you can manage users and folders using:
 
-To enable external authentication you must set the absolute path of your authentication program using `external_auth_program` key in your configuration file.
+- the [web based administration interface](./docs/web-admin.md)
+- the [REST API](./docs/rest-api.md)
+- the sample [REST API CLI](./examples/rest-api-cli)
 
-The external program can read the following environment variables to get info about the user trying to authenticate:
+To support embedded data providers like `bolt` and `SQLite` we can't have a CLI that directly write users and folders to the data provider, we always have to use the REST API.
 
-- `SFTPGO_AUTHD_USERNAME`
-- `SFTPGO_AUTHD_PASSWORD`, not empty for password authentication
-- `SFTPGO_AUTHD_PUBLIC_KEY`, not empty for public key authentication
+## Tutorials
 
-Previous global environment variables aren't cleared when the script is called. The content of these variables is _not_ quoted. They may contain special characters. They are under the control of a possibly malicious remote user.
-The program must respond on the standard output with a valid SFTPGo user serialized as json if the authentication succeed or an user with an empty username if the authentication fails.
-If the authentication succeed the user will be automatically added/updated inside the defined data provider. Actions defined for user added/updated will not be executed in this case.
-The external program should check authentication only, if there are login restrictions such as user disabled, expired, login allowed only from specific IP addresses it is enough to populate the matching user fields and these conditions will be checked in the same way as for built-in users.
-The external auth program must finish within 15 seconds.
-This method is slower than built-in authentication, but it's very flexible as anyone can easily write his own authentication program.
-You can also restrict the authentication scope for the external program using the `external_auth_scope` configuration key:
+Some step-to-step tutorials can be found inside the source tree [howto](./docs/howto "How-to") directory.
 
-- 0 means all supported authetication scopes, the external program will be used for both password and public key authentication
-- 1 means passwords only, the external program will not be used for public key authentication
-- 2 means public keys only, the external program will not be used for password authentication
+## Authentication options
 
-Let's see a very basic example. Our sample authentication program will only accept user `test_user` with any password or public key.
+### External Authentication
 
-```
-#!/bin/sh
+Custom authentication methods can easily be added. SFTPGo supports external authentication modules, and writing a new backend can be as simple as a few lines of shell script. More information can be found [here](./docs/external-auth.md).
 
-if test "$SFTPGO_AUTHD_USERNAME" = "test_user"; then
-  echo '{"status":1,"username":"test_user","expiration_date":0,"home_dir":"/tmp/test_user","uid":0,"gid":0,"max_sessions":0,"quota_size":0,"quota_files":100000,"permissions":{"/":["*"],"/somedir":["list","download"]},"upload_bandwidth":0,"download_bandwidth":0,"filters":{"allowed_ip":[],"denied_ip":[]},"public_keys":[]}'
-else
-  echo '{"username":""}'
-fi
-```
+### Keyboard Interactive Authentication
 
-If you have an external authentication program that could be useful for others too, for example LDAP/Active Directory authentication, please let us know and/or send a pull request.
+Keyboard interactive authentication is, in general, a series of questions asked by the server with responses provided by the client.
+This authentication method is typically used for multi-factor authentication.
+
+More information can be found [here](./docs/keyboard-interactive.md).
+
+## Dynamic user creation or modification
+
+A user can be created or modified by an external program just before the login. More information about this can be found [here](./docs/dynamic-user-mod.md).
 
 ## Custom Actions
 
 SFTPGo allows to configure custom commands and/or HTTP notifications on file upload, download, delete, rename, on SSH commands and on user add, update and delete.
 
-The `actions` struct inside the "sftpd" configuration section allows to configure actions on file upload, download, delete, rename and on SSH commands.
+More information about custom actions can be found [here](./docs/custom-actions.md).
 
-Actions will not be executed if an error is detected and so a partial file is uploaded or downloaded or an SSH command is not successfully completed. The `upload` condition includes both uploads to new files and overwrite of existing files. The `ssh_cmd` condition will be triggered after a command is successfully executed via SSH. `scp` will trigger the `download` and `upload` conditions and not `ssh_cmd`.
+## Virtual folders
 
-The `command`, if defined, is invoked with the following arguments:
+Directories outside the user home directory can be exposed as virtual folders, more information [here](./docs/virtual-folders.md).
 
-- `action`, string, possibile values are: `download`, `upload`, `delete`, `rename`, `ssh_cmd`
-- `username`
-- `path` is the full filesystem path, can be empty for some ssh commands
-- `target_path`, non empty for `rename` action
-- `ssh_cmd`, non empty for `ssh_cmd` action
+## Other hooks
 
-The `command` can also read the following environment variables:
+You can get notified as soon as a new connection is established using the [Post-connect hook](./docs/post-connect-hook.md) and after each login using the [Post-login hook](./docs/post-login-hook.md).
+You can use your own hook to [check passwords](./docs/check-password-hook.md).
 
-- `SFTPGO_ACTION`
-- `SFTPGO_ACTION_USERNAME`
-- `SFTPGO_ACTION_PATH`
-- `SFTPGO_ACTION_TARGET`, non empty for `rename` `SFTPGO_ACTION`
-- `SFTPGO_ACTION_SSH_CMD`, non empty for `ssh_cmd` `SFTPGO_ACTION`
-- `SFTPGO_ACTION_FILE_SIZE`, non empty for `upload`, `download` and `delete` `SFTPGO_ACTION`
+## Storage backends
 
-Previous global environment variables aren't cleared when the script is called.
-The `command` must finish within 30 seconds.
+### S3 Compatible Object Storage backends
 
-The `http_notification_url`, if defined, will contain the following, percent encoded, query string parameters:
+Each user can be mapped to the whole bucket or to a bucket virtual folder. This way, the mapped bucket/virtual folder is exposed over SFTP/SCP/FTP/WebDAV. More information about S3 integration can be found [here](./docs/s3.md).
 
-- `action`
-- `username`
-- `path`
-- `target_path`, added for `rename` action
-- `ssh_cmd`, added for `ssh_cmd` action
-- `file_size`, added for `upload`, `download`, `delete` actions
+### Google Cloud Storage backend
 
-The HTTP request has a 15 seconds timeout.
+Each user can be mapped with a Google Cloud Storage bucket or a bucket virtual folder. This way, the mapped bucket/virtual folder is exposed over SFTP/SCP/FTP/WebDAV. More information about Google Cloud Storage integration can be found [here](./docs/google-cloud-storage.md).
 
-The `actions` struct inside the "data_provider" configuration section allows to configure actions on user add, update, delete.
+### Other Storage backends
 
-Actions will not be fired for internal updates such as the last login or the user quota fields or after external authentication.
+Adding new storage backends is quite easy:
 
-The `command`, if defined, is invoked with the following arguments:
+- implement the [Fs interface](./vfs/vfs.go#L18 "interface for filesystem backends").
+- update the user method `GetFilesystem` to return the new backend
+- update the web interface and the REST API CLI
+- add the flags for the new storage backed to the `portable` mode
 
-- `action`, string, possibile values are: `add`, `update`, `delete`
-- `username`
-- `ID`
-- `status`
-- `expiration_date`
-- `home_dir`
-- `uid`
-- `gid`
+Anyway, some backends require a pay per use account (or they offer free account for a limited time period only). To be able to add support for such backends or to review pull requests, please provide a test account. The test account must be available for enough time to be able to maintain the backend and do basic tests before each new release.
 
-The `command` can also read the following environment variables:
+## Brute force protection
 
-- `SFTPGO_USER_ACTION`
-- `SFTPGO_USER_USERNAME`
-- `SFTPGO_USER_ID`
-- `SFTPGO_USER_STATUS`
-- `SFTPGO_USER_EXPIRATION_DATE`
-- `SFTPGO_USER_HOME_DIR`
-- `SFTPGO_USER_UID`
-- `SFTPGO_USER_GID`
-
-Previous global environment variables aren't cleared when the script is called.
-The `command` must finish within 15 seconds.
-
-The `http_notification_url`, if defined, will be called invoked as http POST. The action is added to the query string, for example `<http_notification_url>?action=update` and the user is sent serialized as json inside the POST body
-
-The HTTP request has a 15 seconds timeout.
-
-## Portable mode
-
-SFTPGo allows to share a single directory on demand using the `portable` subcommand:
-
-```
-sftpgo portable --help
-To serve the current working directory with auto generated credentials simply use:
-
-sftpgo portable
-
-Please take a look at the usage below to customize the serving parameters
-
-Usage:
-  sftpgo portable [flags]
-
-Flags:
-  -C, --advertise-credentials   If the SFTP service is advertised via multicast DNS this flag allows to put username/password inside the advertised TXT record
-  -S, --advertise-service       Advertise SFTP service using multicast DNS (default true)
-  -d, --directory string        Path to the directory to serve. This can be an absolute path or a path relative to the current directory (default ".")
-  -h, --help                    help for portable
-  -l, --log-file-path string    Leave empty to disable logging
-  -p, --password string         Leave empty to use an auto generated value
-  -g, --permissions strings     User's permissions. "*" means any permission (default [list,download])
-  -k, --public-key strings
-  -s, --sftpd-port int          0 means a random non privileged port
-  -c, --ssh-commands strings    SSH commands to enable. "*" means any supported SSH command including scp (default [md5sum,sha1sum,cd,pwd])
-  -u, --username string         Leave empty to use an auto generated value
-```
-
-In portable mode SFTPGo can advertise the SFTP service and, optionally, the credentials via multicast DNS, so there is a standard way to discover the service and to automatically connect to it.
-
-Here is an example of the advertised service including credentials as seen using `avahi-browse`:
-
-```
-= enp0s31f6 IPv4 SFTPGo portable 53705                         SFTP File Transfer   local
-   hostname = [p1.local]
-   address = [192.168.1.230]
-   port = [53705]
-   txt = ["password=EWOo6pJe" "user=user" "version=0.9.3-dev-b409523-dirty-2019-10-26T13:43:32Z"]
-```
+The [connection failed logs](./docs/logs.md) can be used for integration in tools such as [Fail2ban](http://www.fail2ban.org/). Example of [jails](./fail2ban/jails) and [filters](./fail2ban/filters) working with `systemd`/`journald` are available in fail2ban directory.
 
 ## Account's configuration properties
 
-For each account the following properties can be configured:
+Details information about account configuration properties can be found [here](./docs/account.md).
 
-- `username`
-- `password` used for password authentication. For users created using SFTPGo REST API if the password has no known hashing algo prefix it will be stored using argon2id. SFTPGo supports checking passwords stored with bcrypt, pbkdf2, md5crypt and sha512crypt too. For pbkdf2 the supported format is `$<algo>$<iterations>$<salt>$<hashed pwd base64 encoded>`, where algo is `pbkdf2-sha1` or `pbkdf2-sha256` or `pbkdf2-sha512`. For example the `pbkdf2-sha256` of the word `password` using 150000 iterations and `E86a9YMX3zC7` as salt must be stored as `$pbkdf2-sha256$150000$E86a9YMX3zC7$R5J62hsSq+pYw00hLLPKBbcGXmq7fj5+/M0IFoYtZbo=`. For bcrypt the format must be the one supported by golang's [crypto/bcrypt](https://godoc.org/golang.org/x/crypto/bcrypt) package, for example the password `secret` with cost `14` must be stored as `$2a$14$ajq8Q7fbtFRQvXpdCq7Jcuy.Rx1h/L4J60Otx.gyNLbAYctGMJ9tK`. For md5crypt and sha512crypt we support the format used in `/etc/shadow` with the `$1$` and `$6$` prefix, this is useful if you are migrating from Unix system user accounts.  Using the REST API you can send a password hashed as bcrypt, pbkdf2, md5crypt or sha512crypt and it will be stored as is.
-- `public_keys` array of public keys. At least one public key or the password is mandatory.
-- `status` 1 means "active", 0 "inactive". An inactive account cannot login.
-- `expiration_date` expiration date as unix timestamp in milliseconds. An expired account cannot login. 0 means no expiration.
-- `home_dir` The user cannot upload or download files outside this directory. Must be an absolute path.
-- `uid`, `gid`. If sftpgo runs as root system user then the created files and directories will be assigned to this system uid/gid. Ignored on windows and if sftpgo runs as non root user: in this case files and directories for all SFTP users will be owned by the system user that runs sftpgo.
-- `max_sessions` maximum concurrent sessions. 0 means unlimited.
-- `quota_size` maximum size allowed as bytes. 0 means unlimited.
-- `quota_files` maximum number of files allowed. 0 means unlimited.
-- `permissions` the following per directory permissions are supported:
-    - `*` all permissions are granted
-    - `list` list items is allowed
-    - `download` download files is allowed
-    - `upload` upload files is allowed
-    - `overwrite` overwrite an existing file, while uploading, is allowed. `upload` permission is required to allow file overwrite
-    - `delete` delete files or directories is allowed
-    - `rename` rename files or directories is allowed
-    - `create_dirs` create directories is allowed
-    - `create_symlinks` create symbolic links is allowed
-    - `chmod` changing file or directory permissions is allowed. On Windows, only the 0200 bit (owner writable) of mode is used; it controls whether the file's read-only attribute is set or cleared. The other bits are currently unused. Use mode 0400 for a read-only file and 0600 for a readable+writable file.
-    - `chown` changing file or directory owner and group is allowed. Changing owner and group is not supported on Windows.
-    - `chtimes` changing file or directory access and modification time is allowed
-- `upload_bandwidth` maximum upload bandwidth as KB/s, 0 means unlimited.
-- `download_bandwidth` maximum download bandwidth as KB/s, 0 means unlimited.
-- `allowed_ip`, List of IP/Mask allowed to login. Any IP address not contained in this list cannot login. IP/Mask must be in CIDR notation as defined in RFC 4632 and RFC 4291, for example "192.0.2.0/24" or "2001:db8::/32"
-- `denied_ip`, List of IP/Mask not allowed to login. If an IP address is both allowed and denied then login will be denied
+## Performance
 
-These properties are stored inside the data provider.
+SFTPGo can easily saturate a Gigabit connection on low end hardware with no special configuration, this is generally enough for most use cases.
 
-If you want to use your existing accounts you have these options:
+More in-depth analysis of performance can be found [here](./docs/performance.md).
 
-- If your accounts are aleady stored inside a supported database, you can create a database view. Since a view is read only, you have to disable user management and quota tracking so SFTPGo will never try to write to the view
-- you can import your users inside SFTPGo. Take a look at [sftpgo_api_cli.py](./scripts/README.md "sftpgo_api_cli script"), it can convert and import users from Linux system users and Pure-FTPd/ProFTPD virtual users
-- you can use an external authentication program
+## Release Cadence
 
-## REST API
-
-SFTPGo exposes REST API to manage, backup and restore users and to get real time reports of the active connections with possibility of forcibly closing a connection.
-
-If quota tracking is enabled in `sftpgo` configuration file, then the used size and number of files are updated each time a file is added/removed. If files are added/removed not using SFTP/SCP or if you change `track_quota` from `2` to `1`, you can rescan the users home dir and update the used quota using the REST API.
-
-REST API is designed to run on localhost or on a trusted network, if you need HTTPS and/or authentication you can setup a reverse proxy using an HTTP Server such as Apache or NGNIX.
-
-For example you can keep SFTPGo listening on localhost and expose it externally configuring a reverse proxy using Apache HTTP Server this way:
-
-```
-ProxyPass /api/v1 http://127.0.0.1:8080/api/v1
-ProxyPassReverse /api/v1 http://127.0.0.1:8080/api/v1
-```
-
-and you can add authentication with something like this:
-
-```
-<Location /api/v1>
-	AuthType Digest
-	AuthName "Private"
-	AuthDigestDomain "/api/v1"
-	AuthDigestProvider file
-	AuthUserFile "/etc/httpd/conf/auth_digest"
-	Require valid-user
-</Location>
-```
-
-and, of course, you can configure the web server to use HTTPS.
-
-The OpenAPI 3 schema for the exposed API can be found inside the source tree: [openapi.yaml](./httpd/schema/openapi.yaml "OpenAPI 3 specs").
-
-A sample CLI client for the REST API can be found inside the source tree [scripts](./scripts "scripts") directory.
-
-You can also generate your own REST client, in your preferred programming language or even bash scripts, using an OpenAPI generator such as [swagger-codegen](https://github.com/swagger-api/swagger-codegen) or [OpenAPI Generator](https://openapi-generator.tech/)
-
-## Metrics
-
-SFTPGo exposes [Prometheus](https://prometheus.io/) metrics at the `/metrics` HTTP endpoint.
-Several counters and gauges are available, for example:
-
-- Total uploads and downloads
-- Total upload and download size
-- Total upload and download errors
-- Total executed SSH commands
-- Total SSH command errors
-- Number of active connections
-- Data provider availability
-- Total successful and failed logins using a password or a public key
-- Total HTTP requests served and totals for response code
-- Go's runtime details about GC, number of gouroutines and OS threads
-- Process information like CPU, memory, file descriptor usage and start time
-
-Please check the `/metrics` page for more details.
-
-## Web Admin
-
-You can easily build your own interface using the exposed REST API, anyway SFTPGo provides also a very basic built-in web interface that allows to manage users and connections.
-With the default `httpd` configuration, the web admin is available at the following URL:
-
-[http://127.0.0.1:8080/web](http://127.0.0.1:8080/web)
-
-If you need HTTPS and/or authentication you can setup a reverse proxy as explained for the REST API.
-
-## Logs
-
-Inside the log file each line is a JSON struct, each struct has a `sender` fields that identify the log type.
-
-The logs can be divided into the following categories:
-
-- **"app logs"**, internal logs used to debug `sftpgo`:
-    - `sender` string. This is generally the package name that emits the log
-    - `time` string. Date/time with millisecond precision
-    - `level` string
-    - `message` string
-- **"transfer logs"**, SFTP/SCP transfer logs:
-    - `sender` string. `Upload` or `Download`
-    - `time` string. Date/time with millisecond precision
-    - `level` string
-    - `elapsed_ms`, int64. Elapsed time, as milliseconds, for the upload/download
-    - `size_bytes`, int64. Size, as bytes, of the download/upload
-    - `username`, string
-    - `file_path` string
-    - `connection_id` string. Unique connection identifier
-    - `protocol` string. `SFTP` or `SCP`
-- **"command logs"**, SFTP/SCP command logs:
-    - `sender` string. `Rename`, `Rmdir`, `Mkdir`, `Symlink`, `Remove`, `Chmod`, `Chown`, `Chtimes`, `SSHCommand`
-    - `level` string
-    - `username`, string
-    - `file_path` string
-    - `target_path` string
-    - `filemode` string. Valid for sender `Chmod` otherwise empty
-    - `uid` integer. Valid for sender `Chown` otherwise -1
-    - `gid` integer. Valid for sender `Chown` otherwise -1
-    - `access_time` datetime as YYYY-MM-DDTHH:MM:SS. Valid for sender `Chtimes` otherwise empty
-    - `modification_time` datetime as YYYY-MM-DDTHH:MM:SS. Valid for sender `Chtimes` otherwise empty
-    - `ssh_command`, string. Valid for sender `SSHCommand` otherwise empty
-    - `connection_id` string. Unique connection identifier
-    - `protocol` string. `SFTP`, `SCP` or `SSH`
-- **"http logs"**, REST API logs:
-    - `sender` string. `httpd`
-    - `level` string
-    - `remote_addr` string. IP and port of the remote client
-    - `proto` string, for example `HTTP/1.1`
-    - `method` string. HTTP method (`GET`, `POST`, `PUT`, `DELETE` etc.)
-    - `user_agent` string
-    - `uri` string. Full uri
-    - `resp_status` integer. HTTP response status code
-    - `resp_size` integer. Size in bytes of the HTTP response
-    - `elapsed_ms` int64. Elapsed time, as milliseconds, to complete the request
-    - `request_id` string. Unique request identifier
-- **"connection failed logs"**, logs for failed attempts to initialize a connection. A connection can fail for an authentication error or other errors such as a client abort or a timeout if the login does not happen in two minutes
-    - `sender` string. `connection_failed`
-    - `level` string
-    - `username`, string. Can be empty if the connection is closed before an authentication attempt
-    - `client_ip` string.
-    - `login_type` string. Can be `public_key`, `password` or `no_auth_tryed`
-    - `error` string. Optional error description
-
-### Brute force protection
-
-The **connection failed logs** can be used for integration in tools such as [Fail2ban](http://www.fail2ban.org/). Example of [jails](./fail2ban/jails) and [filters](./fail2ban/filters) working with `systemd`/`journald` are available in fail2ban directory.
+SFTPGo releases are feature-driven, we don't have a fixed time based schedule. As a rough estimate, you can expect 1 or 2 new releases per year.
 
 ## Acknowledgements
 
-- [pkg/sftp](https://github.com/pkg/sftp)
-- [go-chi](https://github.com/go-chi/chi)
-- [zerolog](https://github.com/rs/zerolog)
-- [lumberjack](https://gopkg.in/natefinch/lumberjack.v2)
-- [argon2id](https://github.com/alexedwards/argon2id)
-- [go-sqlite3](https://github.com/mattn/go-sqlite3)
-- [go-sql-driver/mysql](https://github.com/go-sql-driver/mysql)
-- [bbolt](https://github.com/etcd-io/bbolt)
-- [lib/pq](https://github.com/lib/pq)
-- [viper](https://github.com/spf13/viper)
-- [cobra](https://github.com/spf13/cobra)
-- [xid](https://github.com/rs/xid)
-- [nathanaelle/password](https://github.com/nathanaelle/password)
-- [ZeroConf](https://github.com/grandcat/zeroconf)
-- [SB Admin 2](https://github.com/BlackrockDigital/startbootstrap-sb-admin-2)
-
-Some code was initially taken from [Pterodactyl sftp server](https://github.com/pterodactyl/sftp-server)
+SFTPGo makes use of the third party libraries listed inside [go.mod](./go.mod).
+Some code was initially taken from [Pterodactyl SFTP Server](https://github.com/pterodactyl/sftp-server).
+We are very grateful to all the people who contributed with ideas and/or pull requests.
 
 ## License
 

SECURITY.md

@@ -0,0 +1,12 @@
+# Security Policy
+
+## Supported Versions
+
+Only the current release of the software is actively supported.  If you need
+help backporting fixes into an older release, feel free to ask.
+
+## Reporting a Vulnerability
+
+Email your vulnerability information to SFTPGo's maintainer:
+
+  Nicola Murino <nicola.murino@gmail.com>

cmd/gen.go

@@ -0,0 +1,12 @@
+package cmd
+
+import "github.com/spf13/cobra"
+
+var genCmd = &cobra.Command{
+	Use:   "gen",
+	Short: "A collection of useful generators",
+}
+
+func init() {
+	rootCmd.AddCommand(genCmd)
+}

cmd/gencompletion.go

@@ -0,0 +1,76 @@
+package cmd
+
+import (
+	"os"
+
+	"github.com/rs/zerolog"
+	"github.com/spf13/cobra"
+
+	"github.com/drakkan/sftpgo/logger"
+)
+
+var genCompletionCmd = &cobra.Command{
+	Use:   "completion [bash|zsh|fish|powershell]",
+	Short: "Generate shell completion script",
+	Long: `To load completions:
+
+Bash:
+
+$ source <(sftpgo gen completion bash)
+
+To load completions for each session, execute once:
+
+Linux:
+
+$ sudo sftpgo gen completion bash > /usr/share/bash-completion/completions/sftpgo
+
+MacOS:
+
+$ sudo sftpgo gen completion bash > /usr/local/etc/bash_completion.d/sftpgo
+
+Zsh:
+
+If shell completion is not already enabled in your environment you will need
+to enable it.  You can execute the following once:
+
+$ echo "autoload -U compinit; compinit" >> ~/.zshrc
+
+To load completions for each session, execute once:
+
+$ sftpgo gen completion zsh > "${fpath[1]}/_sftpgo"
+
+Fish:
+
+$ sftpgo gen completion fish | source
+
+# To load completions for each session, execute once:
+
+$ sftpgo gen completion fish > ~/.config/fish/completions/sftpgo.fish
+`,
+	DisableFlagsInUseLine: true,
+	ValidArgs:             []string{"bash", "zsh", "fish", "powershell"},
+	Args:                  cobra.ExactValidArgs(1),
+	Run: func(cmd *cobra.Command, args []string) {
+		var err error
+		logger.DisableLogger()
+		logger.EnableConsoleLogger(zerolog.DebugLevel)
+		switch args[0] {
+		case "bash":
+			err = cmd.Root().GenBashCompletion(os.Stdout)
+		case "zsh":
+			err = cmd.Root().GenZshCompletion(os.Stdout)
+		case "fish":
+			err = cmd.Root().GenFishCompletion(os.Stdout, true)
+		case "powershell":
+			err = cmd.Root().GenPowerShellCompletion(os.Stdout)
+		}
+		if err != nil {
+			logger.WarnToConsole("Unable to generate shell completion script: %v", err)
+			os.Exit(1)
+		}
+	},
+}
+
+func init() {
+	genCmd.AddCommand(genCompletionCmd)
+}

cmd/genman.go

@@ -0,0 +1,52 @@
+package cmd
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/rs/zerolog"
+	"github.com/spf13/cobra"
+	"github.com/spf13/cobra/doc"
+
+	"github.com/drakkan/sftpgo/logger"
+	"github.com/drakkan/sftpgo/version"
+)
+
+var (
+	manDir    string
+	genManCmd = &cobra.Command{
+		Use:   "man",
+		Short: "Generate man pages for SFTPGo CLI",
+		Long: `This command automatically generates up-to-date man pages of SFTPGo's
+command-line interface.  By default, it creates the man page files
+in the "man" directory under the current directory.
+`,
+		Run: func(cmd *cobra.Command, args []string) {
+			logger.DisableLogger()
+			logger.EnableConsoleLogger(zerolog.DebugLevel)
+			if _, err := os.Stat(manDir); os.IsNotExist(err) {
+				err = os.MkdirAll(manDir, os.ModePerm)
+				if err != nil {
+					logger.WarnToConsole("Unable to generate man page files: %v", err)
+					os.Exit(1)
+				}
+			}
+			header := &doc.GenManHeader{
+				Section: "1",
+				Manual:  "SFTPGo Manual",
+				Source:  fmt.Sprintf("SFTPGo %v", version.Get().Version),
+			}
+			cmd.Root().DisableAutoGenTag = true
+			err := doc.GenManTree(cmd.Root(), header, manDir)
+			if err != nil {
+				logger.WarnToConsole("Unable to generate man page files: %v", err)
+				os.Exit(1)
+			}
+		},
+	}
+)
+
+func init() {
+	genManCmd.Flags().StringVarP(&manDir, "dir", "d", "man", "The directory to write the man pages")
+	genCmd.AddCommand(genManCmd)
+}

cmd/initprovider.go

@@ -0,0 +1,64 @@
+package cmd
+
+import (
+	"os"
+
+	"github.com/rs/zerolog"
+	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
+
+	"github.com/drakkan/sftpgo/config"
+	"github.com/drakkan/sftpgo/dataprovider"
+	"github.com/drakkan/sftpgo/logger"
+	"github.com/drakkan/sftpgo/utils"
+)
+
+var (
+	initProviderCmd = &cobra.Command{
+		Use:   "initprovider",
+		Short: "Initializes and/or updates the configured data provider",
+		Long: `This command reads the data provider connection details from the specified
+configuration file and creates the initial structure or update the existing one,
+as needed.
+
+Some data providers such as bolt and memory does not require an initialization
+but they could require an update to the existing data after upgrading SFTPGo.
+
+For SQLite/bolt providers the database file will be auto-created if missing.
+
+For PostgreSQL and MySQL providers you need to create the configured database,
+this command will create/update the required tables as needed.
+
+To initialize/update the data provider from the configuration directory simply use:
+
+$ sftpgo initprovider
+
+Please take a look at the usage below to customize the options.`,
+		Run: func(cmd *cobra.Command, args []string) {
+			logger.DisableLogger()
+			logger.EnableConsoleLogger(zerolog.DebugLevel)
+			configDir = utils.CleanDirInput(configDir)
+			err := config.LoadConfig(configDir, configFile)
+			if err != nil {
+				logger.WarnToConsole("Unable to initialize data provider, config load error: %v", err)
+				return
+			}
+			providerConf := config.GetProviderConf()
+			logger.InfoToConsole("Initializing provider: %#v config file: %#v", providerConf.Driver, viper.ConfigFileUsed())
+			err = dataprovider.InitializeDatabase(providerConf, configDir)
+			if err == nil {
+				logger.InfoToConsole("Data provider successfully initialized/updated")
+			} else if err == dataprovider.ErrNoInitRequired {
+				logger.InfoToConsole("%v", err.Error())
+			} else {
+				logger.WarnToConsole("Unable to initialize/update the data provider: %v", err)
+				os.Exit(1)
+			}
+		},
+	}
+)
+
+func init() {
+	rootCmd.AddCommand(initProviderCmd)
+	addConfigFlags(initProviderCmd)
+}

cmd/install_windows.go

@@ -2,23 +2,28 @@ package cmd
 
 import (
 	"fmt"
+	"os"
+	"strconv"
+
+	"github.com/spf13/cobra"
 
 	"github.com/drakkan/sftpgo/service"
-	"github.com/spf13/cobra"
+	"github.com/drakkan/sftpgo/utils"
 )
 
 var (
 	installCmd = &cobra.Command{
 		Use:   "install",
 		Short: "Install SFTPGo as Windows Service",
-		Long: `To install the SFTPGo Windows Service with the default values for the command line flags simply use:
+		Long: `To install the SFTPGo Windows Service with the default values for the command
+line flags simply use:
 
 sftpgo service install
 
 Please take a look at the usage below to customize the startup options`,
 		Run: func(cmd *cobra.Command, args []string) {
 			s := service.Service{
-				ConfigDir:     configDir,
+				ConfigDir:     utils.CleanDirInput(configDir),
 				ConfigFile:    configFile,
 				LogFilePath:   logFilePath,
 				LogMaxSize:    logMaxSize,
@@ -39,6 +44,7 @@ Please take a look at the usage below to customize the startup options`,
 			err := winService.Install(serviceArgs...)
 			if err != nil {
 				fmt.Printf("Error installing service: %v\r\n", err)
+				os.Exit(1)
 			} else {
 				fmt.Printf("Service installed!\r\n")
 			}
@@ -50,3 +56,42 @@ func init() {
 	serviceCmd.AddCommand(installCmd)
 	addServeFlags(installCmd)
 }
+
+func getCustomServeFlags() []string {
+	result := []string{}
+	if configDir != defaultConfigDir {
+		configDir = utils.CleanDirInput(configDir)
+		result = append(result, "--"+configDirFlag)
+		result = append(result, configDir)
+	}
+	if configFile != defaultConfigName {
+		result = append(result, "--"+configFileFlag)
+		result = append(result, configFile)
+	}
+	if logFilePath != defaultLogFile {
+		result = append(result, "--"+logFilePathFlag)
+		result = append(result, logFilePath)
+	}
+	if logMaxSize != defaultLogMaxSize {
+		result = append(result, "--"+logMaxSizeFlag)
+		result = append(result, strconv.Itoa(logMaxSize))
+	}
+	if logMaxBackups != defaultLogMaxBackup {
+		result = append(result, "--"+logMaxBackupFlag)
+		result = append(result, strconv.Itoa(logMaxBackups))
+	}
+	if logMaxAge != defaultLogMaxAge {
+		result = append(result, "--"+logMaxAgeFlag)
+		result = append(result, strconv.Itoa(logMaxAge))
+	}
+	if logVerbose != defaultLogVerbose {
+		result = append(result, "--"+logVerboseFlag+"=false")
+	}
+	if logCompress != defaultLogCompress {
+		result = append(result, "--"+logCompressFlag+"=true")
+	}
+	if profiler != defaultProfiler {
+		result = append(result, "--"+profilerFlag+"=true")
+	}
+	return result
+}

cmd/portable.go

@@ -1,12 +1,24 @@
+// +build !noportable
+
 package cmd
 
 import (
+	"encoding/base64"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path"
 	"path/filepath"
+	"strings"
 
+	"github.com/spf13/cobra"
+
+	"github.com/drakkan/sftpgo/common"
 	"github.com/drakkan/sftpgo/dataprovider"
 	"github.com/drakkan/sftpgo/service"
 	"github.com/drakkan/sftpgo/sftpd"
-	"github.com/spf13/cobra"
+	"github.com/drakkan/sftpgo/version"
+	"github.com/drakkan/sftpgo/vfs"
 )
 
 var (
@@ -17,33 +29,99 @@ var (
 	portableUsername             string
 	portablePassword             string
 	portableLogFile              string
+	portableLogVerbose           bool
 	portablePublicKeys           []string
 	portablePermissions          []string
 	portableSSHCommands          []string
+	portableAllowedExtensions    []string
+	portableDeniedExtensions     []string
+	portableFsProvider           int
+	portableS3Bucket             string
+	portableS3Region             string
+	portableS3AccessKey          string
+	portableS3AccessSecret       string
+	portableS3Endpoint           string
+	portableS3StorageClass       string
+	portableS3KeyPrefix          string
+	portableS3ULPartSize         int
+	portableS3ULConcurrency      int
+	portableGCSBucket            string
+	portableGCSCredentialsFile   string
+	portableGCSAutoCredentials   int
+	portableGCSStorageClass      string
+	portableGCSKeyPrefix         string
+	portableFTPDPort             int
+	portableFTPSCert             string
+	portableFTPSKey              string
+	portableWebDAVPort           int
+	portableWebDAVCert           string
+	portableWebDAVKey            string
 	portableCmd                  = &cobra.Command{
 		Use:   "portable",
 		Short: "Serve a single directory",
-		Long: `To serve the current working directory with auto generated credentials simply use:
+		Long: `To serve the current working directory with auto generated credentials simply
+use:
 
-sftpgo portable
+$ sftpgo portable
 
 Please take a look at the usage below to customize the serving parameters`,
 		Run: func(cmd *cobra.Command, args []string) {
 			portableDir := directoryToServe
+			fsProvider := dataprovider.FilesystemProvider(portableFsProvider)
 			if !filepath.IsAbs(portableDir) {
-				portableDir, _ = filepath.Abs(portableDir)
+				if fsProvider == dataprovider.LocalFilesystemProvider {
+					portableDir, _ = filepath.Abs(portableDir)
+				} else {
+					portableDir = os.TempDir()
+				}
 			}
 			permissions := make(map[string][]string)
 			permissions["/"] = portablePermissions
+			portableGCSCredentials := ""
+			if fsProvider == dataprovider.GCSFilesystemProvider && len(portableGCSCredentialsFile) > 0 {
+				fi, err := os.Stat(portableGCSCredentialsFile)
+				if err != nil {
+					fmt.Printf("Invalid GCS credentials file: %v\n", err)
+					os.Exit(1)
+				}
+				if fi.Size() > 1048576 {
+					fmt.Printf("Invalid GCS credentials file: %#v is too big %v/1048576 bytes\n", portableGCSCredentialsFile,
+						fi.Size())
+					os.Exit(1)
+				}
+				creds, err := ioutil.ReadFile(portableGCSCredentialsFile)
+				if err != nil {
+					fmt.Printf("Unable to read credentials file: %v\n", err)
+				}
+				portableGCSCredentials = base64.StdEncoding.EncodeToString(creds)
+				portableGCSAutoCredentials = 0
+			}
+			if portableFTPDPort >= 0 && len(portableFTPSCert) > 0 && len(portableFTPSKey) > 0 {
+				_, err := common.NewCertManager(portableFTPSCert, portableFTPSKey, "FTP portable")
+				if err != nil {
+					fmt.Printf("Unable to load FTPS key pair, cert file %#v key file %#v error: %v\n",
+						portableFTPSCert, portableFTPSKey, err)
+					os.Exit(1)
+				}
+			}
+			if portableWebDAVPort > 0 && len(portableWebDAVCert) > 0 && len(portableWebDAVKey) > 0 {
+				_, err := common.NewCertManager(portableWebDAVCert, portableWebDAVKey, "WebDAV portable")
+				if err != nil {
+					fmt.Printf("Unable to load WebDAV key pair, cert file %#v key file %#v error: %v\n",
+						portableWebDAVCert, portableWebDAVKey, err)
+					os.Exit(1)
+				}
+			}
 			service := service.Service{
-				ConfigDir:     defaultConfigDir,
+				ConfigDir:     filepath.Clean(defaultConfigDir),
 				ConfigFile:    defaultConfigName,
 				LogFilePath:   portableLogFile,
 				LogMaxSize:    defaultLogMaxSize,
 				LogMaxBackups: defaultLogMaxBackup,
 				LogMaxAge:     defaultLogMaxAge,
 				LogCompress:   defaultLogCompress,
-				LogVerbose:    defaultLogVerbose,
+				LogVerbose:    portableLogVerbose,
+				Profiler:      defaultProfiler,
 				Shutdown:      make(chan bool),
 				PortableMode:  1,
 				PortableUser: dataprovider.User{
@@ -53,31 +131,175 @@ Please take a look at the usage below to customize the serving parameters`,
 					Permissions: permissions,
 					HomeDir:     portableDir,
 					Status:      1,
+					FsConfig: dataprovider.Filesystem{
+						Provider: dataprovider.FilesystemProvider(portableFsProvider),
+						S3Config: vfs.S3FsConfig{
+							Bucket:            portableS3Bucket,
+							Region:            portableS3Region,
+							AccessKey:         portableS3AccessKey,
+							AccessSecret:      portableS3AccessSecret,
+							Endpoint:          portableS3Endpoint,
+							StorageClass:      portableS3StorageClass,
+							KeyPrefix:         portableS3KeyPrefix,
+							UploadPartSize:    int64(portableS3ULPartSize),
+							UploadConcurrency: portableS3ULConcurrency,
+						},
+						GCSConfig: vfs.GCSFsConfig{
+							Bucket:               portableGCSBucket,
+							Credentials:          portableGCSCredentials,
+							AutomaticCredentials: portableGCSAutoCredentials,
+							StorageClass:         portableGCSStorageClass,
+							KeyPrefix:            portableGCSKeyPrefix,
+						},
+					},
+					Filters: dataprovider.UserFilters{
+						FileExtensions: parseFileExtensionsFilters(),
+					},
 				},
 			}
-			if err := service.StartPortableMode(portableSFTPDPort, portableSSHCommands, portableAdvertiseService,
-				portableAdvertiseCredentials); err == nil {
+			if err := service.StartPortableMode(portableSFTPDPort, portableFTPDPort, portableWebDAVPort, portableSSHCommands, portableAdvertiseService,
+				portableAdvertiseCredentials, portableFTPSCert, portableFTPSKey, portableWebDAVCert, portableWebDAVKey); err == nil {
 				service.Wait()
+				if service.Error == nil {
+					os.Exit(0)
+				}
 			}
+			os.Exit(1)
 		},
 	}
 )
 
 func init() {
-	portableCmd.Flags().StringVarP(&directoryToServe, "directory", "d", ".",
-		"Path to the directory to serve. This can be an absolute path or a path relative to the current directory")
-	portableCmd.Flags().IntVarP(&portableSFTPDPort, "sftpd-port", "s", 0, "0 means a random non privileged port")
+	version.AddFeature("+portable")
+
+	portableCmd.Flags().StringVarP(&directoryToServe, "directory", "d", ".", `Path to the directory to serve.
+This can be an absolute path or a path
+relative to the current directory
+`)
+	portableCmd.Flags().IntVarP(&portableSFTPDPort, "sftpd-port", "s", 0, "0 means a random unprivileged port")
+	portableCmd.Flags().IntVar(&portableFTPDPort, "ftpd-port", -1, `0 means a random unprivileged port,
+< 0 disabled`)
+	portableCmd.Flags().IntVar(&portableWebDAVPort, "webdav-port", -1, `0 means a random unprivileged port,
+< 0 disabled`)
 	portableCmd.Flags().StringSliceVarP(&portableSSHCommands, "ssh-commands", "c", sftpd.GetDefaultSSHCommands(),
-		"SSH commands to enable. \"*\" means any supported SSH command including scp")
-	portableCmd.Flags().StringVarP(&portableUsername, "username", "u", "", "Leave empty to use an auto generated value")
-	portableCmd.Flags().StringVarP(&portablePassword, "password", "p", "", "Leave empty to use an auto generated value")
+		`SSH commands to enable.
+"*" means any supported SSH command
+including scp
+`)
+	portableCmd.Flags().StringVarP(&portableUsername, "username", "u", "", `Leave empty to use an auto generated
+value`)
+	portableCmd.Flags().StringVarP(&portablePassword, "password", "p", "", `Leave empty to use an auto generated
+value`)
 	portableCmd.Flags().StringVarP(&portableLogFile, logFilePathFlag, "l", "", "Leave empty to disable logging")
+	portableCmd.Flags().BoolVarP(&portableLogVerbose, logVerboseFlag, "v", false, "Enable verbose logs")
 	portableCmd.Flags().StringSliceVarP(&portablePublicKeys, "public-key", "k", []string{}, "")
 	portableCmd.Flags().StringSliceVarP(&portablePermissions, "permissions", "g", []string{"list", "download"},
-		"User's permissions. \"*\" means any permission")
-	portableCmd.Flags().BoolVarP(&portableAdvertiseService, "advertise-service", "S", true,
-		"Advertise SFTP service using multicast DNS")
+		`User's permissions. "*" means any
+permission`)
+	portableCmd.Flags().StringArrayVar(&portableAllowedExtensions, "allowed-extensions", []string{},
+		`Allowed file extensions case
+insensitive. The format is
+/dir::ext1,ext2.
+For example: "/somedir::.jpg,.png"`)
+	portableCmd.Flags().StringArrayVar(&portableDeniedExtensions, "denied-extensions", []string{},
+		`Denied file extensions case
+insensitive. The format is
+/dir::ext1,ext2.
+For example: "/somedir::.jpg,.png"`)
+	portableCmd.Flags().BoolVarP(&portableAdvertiseService, "advertise-service", "S", false,
+		`Advertise SFTP/FTP service using
+multicast DNS`)
 	portableCmd.Flags().BoolVarP(&portableAdvertiseCredentials, "advertise-credentials", "C", false,
-		"If the SFTP service is advertised via multicast DNS this flag allows to put username/password inside the advertised TXT record")
+		`If the SFTP/FTP service is
+advertised via multicast DNS, this
+flag allows to put username/password
+inside the advertised TXT record`)
+	portableCmd.Flags().IntVarP(&portableFsProvider, "fs-provider", "f", int(dataprovider.LocalFilesystemProvider), `0 means local filesystem,
+1 Amazon S3 compatible,
+2 Google Cloud Storage`)
+	portableCmd.Flags().StringVar(&portableS3Bucket, "s3-bucket", "", "")
+	portableCmd.Flags().StringVar(&portableS3Region, "s3-region", "", "")
+	portableCmd.Flags().StringVar(&portableS3AccessKey, "s3-access-key", "", "")
+	portableCmd.Flags().StringVar(&portableS3AccessSecret, "s3-access-secret", "", "")
+	portableCmd.Flags().StringVar(&portableS3Endpoint, "s3-endpoint", "", "")
+	portableCmd.Flags().StringVar(&portableS3StorageClass, "s3-storage-class", "", "")
+	portableCmd.Flags().StringVar(&portableS3KeyPrefix, "s3-key-prefix", "", `Allows to restrict access to the
+virtual folder identified by this
+prefix and its contents`)
+	portableCmd.Flags().IntVar(&portableS3ULPartSize, "s3-upload-part-size", 5, `The buffer size for multipart uploads
+(MB)`)
+	portableCmd.Flags().IntVar(&portableS3ULConcurrency, "s3-upload-concurrency", 2, `How many parts are uploaded in
+parallel`)
+	portableCmd.Flags().StringVar(&portableGCSBucket, "gcs-bucket", "", "")
+	portableCmd.Flags().StringVar(&portableGCSStorageClass, "gcs-storage-class", "", "")
+	portableCmd.Flags().StringVar(&portableGCSKeyPrefix, "gcs-key-prefix", "", `Allows to restrict access to the
+virtual folder identified by this
+prefix and its contents`)
+	portableCmd.Flags().StringVar(&portableGCSCredentialsFile, "gcs-credentials-file", "", `Google Cloud Storage JSON credentials
+file`)
+	portableCmd.Flags().IntVar(&portableGCSAutoCredentials, "gcs-automatic-credentials", 1, `0 means explicit credentials using
+a JSON credentials file, 1 automatic
+`)
+	portableCmd.Flags().StringVar(&portableFTPSCert, "ftpd-cert", "", "Path to the certificate file for FTPS")
+	portableCmd.Flags().StringVar(&portableFTPSKey, "ftpd-key", "", "Path to the key file for FTPS")
+	portableCmd.Flags().StringVar(&portableWebDAVCert, "webdav-cert", "", `Path to the certificate file for WebDAV
+over HTTPS`)
+	portableCmd.Flags().StringVar(&portableWebDAVKey, "webdav-key", "", `Path to the key file for WebDAV over
+HTTPS`)
 	rootCmd.AddCommand(portableCmd)
 }
+
+func parseFileExtensionsFilters() []dataprovider.ExtensionsFilter {
+	var extensions []dataprovider.ExtensionsFilter
+	for _, val := range portableAllowedExtensions {
+		p, exts := getExtensionsFilterValues(strings.TrimSpace(val))
+		if len(p) > 0 {
+			extensions = append(extensions, dataprovider.ExtensionsFilter{
+				Path:              path.Clean(p),
+				AllowedExtensions: exts,
+				DeniedExtensions:  []string{},
+			})
+		}
+	}
+	for _, val := range portableDeniedExtensions {
+		p, exts := getExtensionsFilterValues(strings.TrimSpace(val))
+		if len(p) > 0 {
+			found := false
+			for index, e := range extensions {
+				if path.Clean(e.Path) == path.Clean(p) {
+					extensions[index].DeniedExtensions = append(extensions[index].DeniedExtensions, exts...)
+					found = true
+					break
+				}
+			}
+			if !found {
+				extensions = append(extensions, dataprovider.ExtensionsFilter{
+					Path:              path.Clean(p),
+					AllowedExtensions: []string{},
+					DeniedExtensions:  exts,
+				})
+			}
+		}
+	}
+	return extensions
+}
+
+func getExtensionsFilterValues(value string) (string, []string) {
+	if strings.Contains(value, "::") {
+		dirExts := strings.Split(value, "::")
+		if len(dirExts) > 1 {
+			dir := strings.TrimSpace(dirExts[0])
+			exts := []string{}
+			for _, e := range strings.Split(dirExts[1], ",") {
+				cleanedExt := strings.TrimSpace(e)
+				if len(cleanedExt) > 0 {
+					exts = append(exts, cleanedExt)
+				}
+			}
+			if len(dir) > 0 && len(exts) > 0 {
+				return dir, exts
+			}
+		}
+	}
+	return "", nil
+}

cmd/portable_disabled.go

@@ -0,0 +1,9 @@
+// +build noportable
+
+package cmd
+
+import "github.com/drakkan/sftpgo/version"
+
+func init() {
+	version.AddFeature("-portable")
+}

cmd/reload_windows.go

@@ -0,0 +1,35 @@
+package cmd
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/spf13/cobra"
+
+	"github.com/drakkan/sftpgo/service"
+)
+
+var (
+	reloadCmd = &cobra.Command{
+		Use:   "reload",
+		Short: "Reload the SFTPGo Windows Service sending a \"paramchange\" request",
+		Run: func(cmd *cobra.Command, args []string) {
+			s := service.WindowsService{
+				Service: service.Service{
+					Shutdown: make(chan bool),
+				},
+			}
+			err := s.Reload()
+			if err != nil {
+				fmt.Printf("Error sending reload signal: %v\r\n", err)
+				os.Exit(1)
+			} else {
+				fmt.Printf("Reload signal sent!\r\n")
+			}
+		},
+	}
+)
+
+func init() {
+	serviceCmd.AddCommand(reloadCmd)
+}

cmd/root.go

@@ -4,16 +4,15 @@ package cmd
 import (
 	"fmt"
 	"os"
-	"strconv"
 
-	"github.com/drakkan/sftpgo/config"
-	"github.com/drakkan/sftpgo/utils"
 	"github.com/spf13/cobra"
 	"github.com/spf13/viper"
+
+	"github.com/drakkan/sftpgo/config"
+	"github.com/drakkan/sftpgo/version"
 )
 
 const (
-	logSender           = "cmd"
 	configDirFlag       = "config-dir"
 	configDirKey        = "config_dir"
 	configFileFlag      = "config-file"
@@ -30,6 +29,8 @@ const (
 	logCompressKey      = "log_compress"
 	logVerboseFlag      = "log-verbose"
 	logVerboseKey       = "log_verbose"
+	profilerFlag        = "profiler"
+	profilerKey         = "profiler"
 	defaultConfigDir    = "."
 	defaultConfigName   = config.DefaultConfigName
 	defaultLogFile      = "sftpgo.log"
@@ -38,6 +39,7 @@ const (
 	defaultLogMaxAge    = 28
 	defaultLogCompress  = false
 	defaultLogVerbose   = true
+	defaultProfiler     = false
 )
 
 var (
@@ -49,18 +51,18 @@ var (
 	logMaxAge     int
 	logCompress   bool
 	logVerbose    bool
+	profiler      bool
 
 	rootCmd = &cobra.Command{
 		Use:   "sftpgo",
-		Short: "Full featured and highly configurable SFTP server",
+		Short: "Fully featured and highly configurable SFTP server",
 	}
 )
 
 func init() {
-	version := utils.GetAppVersion()
 	rootCmd.Flags().BoolP("version", "v", false, "")
-	rootCmd.Version = version.GetVersionAsString()
-	rootCmd.SetVersionTemplate(`{{printf "SFTPGo version: "}}{{printf "%s" .Version}}
+	rootCmd.Version = version.GetAsString()
+	rootCmd.SetVersionTemplate(`{{printf "SFTPGo "}}{{printf "%s" .Version}}
 `)
 }
 
@@ -73,97 +75,101 @@ func Execute() {
 	}
 }
 
-func addServeFlags(cmd *cobra.Command) {
+func addConfigFlags(cmd *cobra.Command) {
 	viper.SetDefault(configDirKey, defaultConfigDir)
-	viper.BindEnv(configDirKey, "SFTPGO_CONFIG_DIR")
+	viper.BindEnv(configDirKey, "SFTPGO_CONFIG_DIR") //nolint:errcheck // err is not nil only if the key to bind is missing
 	cmd.Flags().StringVarP(&configDir, configDirFlag, "c", viper.GetString(configDirKey),
-		"Location for SFTPGo config dir. This directory should contain the \"sftpgo\" configuration file or the configured "+
-			"config-file and it is used as the base for files with a relative path (eg. the private keys for the SFTP server, "+
-			"the SQLite database if you use SQLite as data provider). This flag can be set using SFTPGO_CONFIG_DIR env var too.")
-	viper.BindPFlag(configDirKey, cmd.Flags().Lookup(configDirFlag))
+		`Location for SFTPGo config dir. This directory
+should contain the "sftpgo" configuration file
+or the configured config-file and it is used as
+the base for files with a relative path (eg. the
+private keys for the SFTP server, the SQLite
+database if you use SQLite as data provider).
+This flag can be set using SFTPGO_CONFIG_DIR
+env var too.`)
+	viper.BindPFlag(configDirKey, cmd.Flags().Lookup(configDirFlag)) //nolint:errcheck
 
 	viper.SetDefault(configFileKey, defaultConfigName)
-	viper.BindEnv(configFileKey, "SFTPGO_CONFIG_FILE")
+	viper.BindEnv(configFileKey, "SFTPGO_CONFIG_FILE") //nolint:errcheck
 	cmd.Flags().StringVarP(&configFile, configFileFlag, "f", viper.GetString(configFileKey),
-		"Name for SFTPGo configuration file. It must be the name of a file stored in config-dir not the absolute path to the "+
-			"configuration file. The specified file name must have no extension we automatically load JSON, YAML, TOML, HCL and "+
-			"Java properties. Therefore if you set \"sftpgo\" then \"sftpgo.json\", \"sftpgo.yaml\" and so on are searched. "+
-			"This flag can be set using SFTPGO_CONFIG_FILE env var too.")
-	viper.BindPFlag(configFileKey, cmd.Flags().Lookup(configFileFlag))
+		`Name for SFTPGo configuration file. It must be
+the name of a file stored in config-dir not the
+absolute path to the configuration file. The
+specified file name must have no extension we
+automatically load JSON, YAML, TOML, HCL and
+Java properties. Therefore if you set "sftpgo"
+then "sftpgo.json", "sftpgo.yaml" and so on
+are searched.
+This flag can be set using SFTPGO_CONFIG_FILE
+env var too.`)
+	viper.BindPFlag(configFileKey, cmd.Flags().Lookup(configFileFlag)) //nolint:errcheck
+}
+
+func addServeFlags(cmd *cobra.Command) {
+	addConfigFlags(cmd)
 
 	viper.SetDefault(logFilePathKey, defaultLogFile)
-	viper.BindEnv(logFilePathKey, "SFTPGO_LOG_FILE_PATH")
+	viper.BindEnv(logFilePathKey, "SFTPGO_LOG_FILE_PATH") //nolint:errcheck
 	cmd.Flags().StringVarP(&logFilePath, logFilePathFlag, "l", viper.GetString(logFilePathKey),
-		"Location for the log file. Leave empty to write logs to the standard output. This flag can be set using SFTPGO_LOG_FILE_PATH "+
-			"env var too.")
-	viper.BindPFlag(logFilePathKey, cmd.Flags().Lookup(logFilePathFlag))
+		`Location for the log file. Leave empty to write
+logs to the standard output. This flag can be
+set using SFTPGO_LOG_FILE_PATH env var too.
+`)
+	viper.BindPFlag(logFilePathKey, cmd.Flags().Lookup(logFilePathFlag)) //nolint:errcheck
 
 	viper.SetDefault(logMaxSizeKey, defaultLogMaxSize)
-	viper.BindEnv(logMaxSizeKey, "SFTPGO_LOG_MAX_SIZE")
+	viper.BindEnv(logMaxSizeKey, "SFTPGO_LOG_MAX_SIZE") //nolint:errcheck
 	cmd.Flags().IntVarP(&logMaxSize, logMaxSizeFlag, "s", viper.GetInt(logMaxSizeKey),
-		"Maximum size in megabytes of the log file before it gets rotated. This flag can be set using SFTPGO_LOG_MAX_SIZE "+
-			"env var too. It is unused if log-file-path is empty.")
-	viper.BindPFlag(logMaxSizeKey, cmd.Flags().Lookup(logMaxSizeFlag))
+		`Maximum size in megabytes of the log file
+before it gets rotated. This flag can be set
+using SFTPGO_LOG_MAX_SIZE env var too. It is
+unused if log-file-path is empty.
+`)
+	viper.BindPFlag(logMaxSizeKey, cmd.Flags().Lookup(logMaxSizeFlag)) //nolint:errcheck
 
 	viper.SetDefault(logMaxBackupKey, defaultLogMaxBackup)
-	viper.BindEnv(logMaxBackupKey, "SFTPGO_LOG_MAX_BACKUPS")
+	viper.BindEnv(logMaxBackupKey, "SFTPGO_LOG_MAX_BACKUPS") //nolint:errcheck
 	cmd.Flags().IntVarP(&logMaxBackups, "log-max-backups", "b", viper.GetInt(logMaxBackupKey),
-		"Maximum number of old log files to retain. This flag can be set using SFTPGO_LOG_MAX_BACKUPS env var too. "+
-			"It is unused if log-file-path is empty.")
-	viper.BindPFlag(logMaxBackupKey, cmd.Flags().Lookup(logMaxBackupFlag))
+		`Maximum number of old log files to retain.
+This flag can be set using SFTPGO_LOG_MAX_BACKUPS
+env var too. It is unused if log-file-path is
+empty.`)
+	viper.BindPFlag(logMaxBackupKey, cmd.Flags().Lookup(logMaxBackupFlag)) //nolint:errcheck
 
 	viper.SetDefault(logMaxAgeKey, defaultLogMaxAge)
-	viper.BindEnv(logMaxAgeKey, "SFTPGO_LOG_MAX_AGE")
+	viper.BindEnv(logMaxAgeKey, "SFTPGO_LOG_MAX_AGE") //nolint:errcheck
 	cmd.Flags().IntVarP(&logMaxAge, "log-max-age", "a", viper.GetInt(logMaxAgeKey),
-		"Maximum number of days to retain old log files. This flag can be set using SFTPGO_LOG_MAX_AGE env var too. "+
-			"It is unused if log-file-path is empty.")
-	viper.BindPFlag(logMaxAgeKey, cmd.Flags().Lookup(logMaxAgeFlag))
+		`Maximum number of days to retain old log files.
+This flag can be set using SFTPGO_LOG_MAX_AGE env
+var too. It is unused if log-file-path is empty.
+`)
+	viper.BindPFlag(logMaxAgeKey, cmd.Flags().Lookup(logMaxAgeFlag)) //nolint:errcheck
 
 	viper.SetDefault(logCompressKey, defaultLogCompress)
-	viper.BindEnv(logCompressKey, "SFTPGO_LOG_COMPRESS")
-	cmd.Flags().BoolVarP(&logCompress, logCompressFlag, "z", viper.GetBool(logCompressKey), "Determine if the rotated "+
-		"log files should be compressed using gzip. This flag can be set using SFTPGO_LOG_COMPRESS env var too. "+
-		"It is unused if log-file-path is empty.")
-	viper.BindPFlag(logCompressKey, cmd.Flags().Lookup(logCompressFlag))
+	viper.BindEnv(logCompressKey, "SFTPGO_LOG_COMPRESS") //nolint:errcheck
+	cmd.Flags().BoolVarP(&logCompress, logCompressFlag, "z", viper.GetBool(logCompressKey),
+		`Determine if the rotated log files
+should be compressed using gzip. This flag can
+be set using SFTPGO_LOG_COMPRESS env var too.
+It is unused if log-file-path is empty.
+`)
+	viper.BindPFlag(logCompressKey, cmd.Flags().Lookup(logCompressFlag)) //nolint:errcheck
 
 	viper.SetDefault(logVerboseKey, defaultLogVerbose)
-	viper.BindEnv(logVerboseKey, "SFTPGO_LOG_VERBOSE")
-	cmd.Flags().BoolVarP(&logVerbose, logVerboseFlag, "v", viper.GetBool(logVerboseKey), "Enable verbose logs. "+
-		"This flag can be set using SFTPGO_LOG_VERBOSE env var too.")
-	viper.BindPFlag(logVerboseKey, cmd.Flags().Lookup(logVerboseFlag))
-}
+	viper.BindEnv(logVerboseKey, "SFTPGO_LOG_VERBOSE") //nolint:errcheck
+	cmd.Flags().BoolVarP(&logVerbose, logVerboseFlag, "v", viper.GetBool(logVerboseKey),
+		`Enable verbose logs. This flag can be set
+using SFTPGO_LOG_VERBOSE env var too.
+`)
+	viper.BindPFlag(logVerboseKey, cmd.Flags().Lookup(logVerboseFlag)) //nolint:errcheck
 
-func getCustomServeFlags() []string {
-	result := []string{}
-	if configDir != defaultConfigDir {
-		result = append(result, "--"+configDirFlag)
-		result = append(result, configDir)
-	}
-	if configFile != defaultConfigName {
-		result = append(result, "--"+configFileFlag)
-		result = append(result, configFile)
-	}
-	if logFilePath != defaultLogFile {
-		result = append(result, "--"+logFilePathFlag)
-		result = append(result, logFilePath)
-	}
-	if logMaxSize != defaultLogMaxSize {
-		result = append(result, "--"+logMaxSizeFlag)
-		result = append(result, strconv.Itoa(logMaxSize))
-	}
-	if logMaxBackups != defaultLogMaxBackup {
-		result = append(result, "--"+logMaxBackupFlag)
-		result = append(result, strconv.Itoa(logMaxBackups))
-	}
-	if logMaxAge != defaultLogMaxAge {
-		result = append(result, "--"+logMaxAgeFlag)
-		result = append(result, strconv.Itoa(logMaxAge))
-	}
-	if logVerbose != defaultLogVerbose {
-		result = append(result, "--"+logVerboseFlag+"=false")
-	}
-	if logCompress != defaultLogCompress {
-		result = append(result, "--"+logCompressFlag+"=true")
-	}
-	return result
+	viper.SetDefault(profilerKey, defaultProfiler)
+	viper.BindEnv(profilerKey, "SFTPGO_PROFILER") //nolint:errcheck
+	cmd.Flags().BoolVarP(&profiler, profilerFlag, "p", viper.GetBool(profilerKey),
+		`Enable the built-in profiler. The profiler will
+be accessible via HTTP/HTTPS using the base URL
+"/debug/pprof/".
+This flag can be set using SFTPGO_PROFILER env
+var too.`)
+	viper.BindPFlag(profilerKey, cmd.Flags().Lookup(profilerFlag)) //nolint:errcheck
 }

cmd/rotatelogs_windows.go

@@ -0,0 +1,35 @@
+package cmd
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/spf13/cobra"
+
+	"github.com/drakkan/sftpgo/service"
+)
+
+var (
+	rotateLogCmd = &cobra.Command{
+		Use:   "rotatelogs",
+		Short: "Signal to the running service to rotate the logs",
+		Run: func(cmd *cobra.Command, args []string) {
+			s := service.WindowsService{
+				Service: service.Service{
+					Shutdown: make(chan bool),
+				},
+			}
+			err := s.RotateLogFile()
+			if err != nil {
+				fmt.Printf("Error sending rotate log file signal to the service: %v\r\n", err)
+				os.Exit(1)
+			} else {
+				fmt.Printf("Rotate log file signal sent!\r\n")
+			}
+		},
+	}
+)
+
+func init() {
+	serviceCmd.AddCommand(rotateLogCmd)
+}

cmd/serve.go

@@ -1,22 +1,27 @@
 package cmd
 
 import (
-	"github.com/drakkan/sftpgo/service"
+	"os"
+
 	"github.com/spf13/cobra"
+
+	"github.com/drakkan/sftpgo/service"
+	"github.com/drakkan/sftpgo/utils"
 )
 
 var (
 	serveCmd = &cobra.Command{
 		Use:   "serve",
 		Short: "Start the SFTP Server",
-		Long: `To start the SFTPGo with the default values for the command line flags simply use:
+		Long: `To start the SFTPGo with the default values for the command line flags simply
+use:
 
-sftpgo serve
+$ sftpgo serve
 
 Please take a look at the usage below to customize the startup options`,
 		Run: func(cmd *cobra.Command, args []string) {
 			service := service.Service{
-				ConfigDir:     configDir,
+				ConfigDir:     utils.CleanDirInput(configDir),
 				ConfigFile:    configFile,
 				LogFilePath:   logFilePath,
 				LogMaxSize:    logMaxSize,
@@ -24,11 +29,16 @@ Please take a look at the usage below to customize the startup options`,
 				LogMaxAge:     logMaxAge,
 				LogCompress:   logCompress,
 				LogVerbose:    logVerbose,
+				Profiler:      profiler,
 				Shutdown:      make(chan bool),
 			}
 			if err := service.Start(); err == nil {
 				service.Wait()
+				if service.Error == nil {
+					os.Exit(0)
+				}
 			}
+			os.Exit(1)
 		},
 	}
 )

cmd/service_windows.go

@@ -7,7 +7,7 @@ import (
 var (
 	serviceCmd = &cobra.Command{
 		Use:   "service",
-		Short: "Install, Uninstall, Start, Stop and retrieve status for SFTPGo Windows Service",
+		Short: "Manage SFTPGo Windows Service",
 	}
 )
 

cmd/start_windows.go

@@ -2,9 +2,13 @@ package cmd
 
 import (
 	"fmt"
+	"os"
+	"path/filepath"
+
+	"github.com/spf13/cobra"
 
 	"github.com/drakkan/sftpgo/service"
-	"github.com/spf13/cobra"
+	"github.com/drakkan/sftpgo/utils"
 )
 
 var (
@@ -12,6 +16,10 @@ var (
 		Use:   "start",
 		Short: "Start SFTPGo Windows Service",
 		Run: func(cmd *cobra.Command, args []string) {
+			configDir = utils.CleanDirInput(configDir)
+			if !filepath.IsAbs(logFilePath) && utils.IsFileInputValid(logFilePath) {
+				logFilePath = filepath.Join(configDir, logFilePath)
+			}
 			s := service.Service{
 				ConfigDir:     configDir,
 				ConfigFile:    configFile,
@@ -21,6 +29,7 @@ var (
 				LogMaxAge:     logMaxAge,
 				LogCompress:   logCompress,
 				LogVerbose:    logVerbose,
+				Profiler:      profiler,
 				Shutdown:      make(chan bool),
 			}
 			winService := service.WindowsService{
@@ -29,6 +38,7 @@ var (
 			err := winService.RunService()
 			if err != nil {
 				fmt.Printf("Error starting service: %v\r\n", err)
+				os.Exit(1)
 			} else {
 				fmt.Printf("Service started!\r\n")
 			}

cmd/status_windows.go

@@ -2,9 +2,11 @@ package cmd
 
 import (
 	"fmt"
+	"os"
+
+	"github.com/spf13/cobra"
 
 	"github.com/drakkan/sftpgo/service"
-	"github.com/spf13/cobra"
 )
 
 var (
@@ -20,6 +22,7 @@ var (
 			status, err := s.Status()
 			if err != nil {
 				fmt.Printf("Error querying service status: %v\r\n", err)
+				os.Exit(1)
 			} else {
 				fmt.Printf("Service status: %#v\r\n", status.String())
 			}

cmd/stop_windows.go

@@ -2,9 +2,11 @@ package cmd
 
 import (
 	"fmt"
+	"os"
+
+	"github.com/spf13/cobra"
 
 	"github.com/drakkan/sftpgo/service"
-	"github.com/spf13/cobra"
 )
 
 var (
@@ -20,6 +22,7 @@ var (
 			err := s.Stop()
 			if err != nil {
 				fmt.Printf("Error stopping service: %v\r\n", err)
+				os.Exit(1)
 			} else {
 				fmt.Printf("Service stopped!\r\n")
 			}

cmd/uninstall_windows.go

@@ -2,9 +2,11 @@ package cmd
 
 import (
 	"fmt"
+	"os"
+
+	"github.com/spf13/cobra"
 
 	"github.com/drakkan/sftpgo/service"
-	"github.com/spf13/cobra"
 )
 
 var (
@@ -20,6 +22,7 @@ var (
 			err := s.Uninstall()
 			if err != nil {
 				fmt.Printf("Error removing service: %v\r\n", err)
+				os.Exit(1)
 			} else {
 				fmt.Printf("Service uninstalled\r\n")
 			}

common/actions.go

@@ -0,0 +1,157 @@
+package common
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"net/http"
+	"net/url"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"time"
+
+	"github.com/drakkan/sftpgo/dataprovider"
+	"github.com/drakkan/sftpgo/httpclient"
+	"github.com/drakkan/sftpgo/logger"
+	"github.com/drakkan/sftpgo/utils"
+)
+
+var (
+	errUnconfiguredAction    = errors.New("no hook is configured for this action")
+	errNoHook                = errors.New("unable to execute action, no hook defined")
+	errUnexpectedHTTResponse = errors.New("unexpected HTTP response code")
+)
+
+// ProtocolActions defines the action to execute on file operations and SSH commands
+type ProtocolActions struct {
+	// Valid values are download, upload, pre-delete, delete, rename, ssh_cmd. Empty slice to disable
+	ExecuteOn []string `json:"execute_on" mapstructure:"execute_on"`
+	// Absolute path to an external program or an HTTP URL
+	Hook string `json:"hook" mapstructure:"hook"`
+}
+
+// actionNotification defines a notification for a Protocol Action
+type actionNotification struct {
+	Action     string `json:"action"`
+	Username   string `json:"username"`
+	Path       string `json:"path"`
+	TargetPath string `json:"target_path,omitempty"`
+	SSHCmd     string `json:"ssh_cmd,omitempty"`
+	FileSize   int64  `json:"file_size,omitempty"`
+	FsProvider int    `json:"fs_provider"`
+	Bucket     string `json:"bucket,omitempty"`
+	Endpoint   string `json:"endpoint,omitempty"`
+	Status     int    `json:"status"`
+	Protocol   string `json:"protocol"`
+}
+
+// SSHCommandActionNotification executes the defined action for the specified SSH command
+func SSHCommandActionNotification(user *dataprovider.User, filePath, target, sshCmd string, err error) {
+	action := newActionNotification(user, operationSSHCmd, filePath, target, sshCmd, ProtocolSSH, 0, err)
+	go action.execute() //nolint:errcheck
+}
+
+func newActionNotification(user *dataprovider.User, operation, filePath, target, sshCmd, protocol string, fileSize int64,
+	err error) actionNotification {
+	bucket := ""
+	endpoint := ""
+	status := 1
+	if user.FsConfig.Provider == dataprovider.S3FilesystemProvider {
+		bucket = user.FsConfig.S3Config.Bucket
+		endpoint = user.FsConfig.S3Config.Endpoint
+	} else if user.FsConfig.Provider == dataprovider.GCSFilesystemProvider {
+		bucket = user.FsConfig.GCSConfig.Bucket
+	}
+	if err == ErrQuotaExceeded {
+		status = 2
+	} else if err != nil {
+		status = 0
+	}
+	return actionNotification{
+		Action:     operation,
+		Username:   user.Username,
+		Path:       filePath,
+		TargetPath: target,
+		SSHCmd:     sshCmd,
+		FileSize:   fileSize,
+		FsProvider: int(user.FsConfig.Provider),
+		Bucket:     bucket,
+		Endpoint:   endpoint,
+		Status:     status,
+		Protocol:   protocol,
+	}
+}
+
+func (a *actionNotification) asJSON() []byte {
+	res, _ := json.Marshal(a)
+	return res
+}
+
+func (a *actionNotification) asEnvVars() []string {
+	return []string{fmt.Sprintf("SFTPGO_ACTION=%v", a.Action),
+		fmt.Sprintf("SFTPGO_ACTION_USERNAME=%v", a.Username),
+		fmt.Sprintf("SFTPGO_ACTION_PATH=%v", a.Path),
+		fmt.Sprintf("SFTPGO_ACTION_TARGET=%v", a.TargetPath),
+		fmt.Sprintf("SFTPGO_ACTION_SSH_CMD=%v", a.SSHCmd),
+		fmt.Sprintf("SFTPGO_ACTION_FILE_SIZE=%v", a.FileSize),
+		fmt.Sprintf("SFTPGO_ACTION_FS_PROVIDER=%v", a.FsProvider),
+		fmt.Sprintf("SFTPGO_ACTION_BUCKET=%v", a.Bucket),
+		fmt.Sprintf("SFTPGO_ACTION_ENDPOINT=%v", a.Endpoint),
+		fmt.Sprintf("SFTPGO_ACTION_STATUS=%v", a.Status),
+		fmt.Sprintf("SFTPGO_ACTION_PROTOCOL=%v", a.Protocol),
+	}
+}
+
+func (a *actionNotification) executeNotificationCommand() error {
+	if !filepath.IsAbs(Config.Actions.Hook) {
+		err := fmt.Errorf("invalid notification command %#v", Config.Actions.Hook)
+		logger.Warn(a.Protocol, "", "unable to execute notification command: %v", err)
+		return err
+	}
+	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+	defer cancel()
+	cmd := exec.CommandContext(ctx, Config.Actions.Hook, a.Action, a.Username, a.Path, a.TargetPath, a.SSHCmd)
+	cmd.Env = append(os.Environ(), a.asEnvVars()...)
+	startTime := time.Now()
+	err := cmd.Run()
+	logger.Debug(a.Protocol, "", "executed command %#v with arguments: %#v, %#v, %#v, %#v, %#v, elapsed: %v, error: %v",
+		Config.Actions.Hook, a.Action, a.Username, a.Path, a.TargetPath, a.SSHCmd, time.Since(startTime), err)
+	return err
+}
+
+func (a *actionNotification) execute() error {
+	if !utils.IsStringInSlice(a.Action, Config.Actions.ExecuteOn) {
+		return errUnconfiguredAction
+	}
+	if len(Config.Actions.Hook) == 0 {
+		logger.Warn(a.Protocol, "", "Unable to send notification, no hook is defined")
+		return errNoHook
+	}
+	if strings.HasPrefix(Config.Actions.Hook, "http") {
+		var url *url.URL
+		url, err := url.Parse(Config.Actions.Hook)
+		if err != nil {
+			logger.Warn(a.Protocol, "", "Invalid hook %#v for operation %#v: %v", Config.Actions.Hook, a.Action, err)
+			return err
+		}
+		startTime := time.Now()
+		httpClient := httpclient.GetHTTPClient()
+		resp, err := httpClient.Post(url.String(), "application/json", bytes.NewBuffer(a.asJSON()))
+		respCode := 0
+		if err == nil {
+			respCode = resp.StatusCode
+			resp.Body.Close()
+			if respCode != http.StatusOK {
+				err = errUnexpectedHTTResponse
+			}
+		}
+		logger.Debug(a.Protocol, "", "notified operation %#v to URL: %v status code: %v, elapsed: %v err: %v",
+			a.Action, url.String(), respCode, time.Since(startTime), err)
+		return err
+	}
+	return a.executeNotificationCommand()
+}

common/actions_test.go

@@ -0,0 +1,181 @@
+package common
+
+import (
+	"errors"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"runtime"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	"github.com/drakkan/sftpgo/dataprovider"
+	"github.com/drakkan/sftpgo/vfs"
+)
+
+func TestNewActionNotification(t *testing.T) {
+	user := &dataprovider.User{
+		Username: "username",
+	}
+	user.FsConfig.Provider = dataprovider.LocalFilesystemProvider
+	user.FsConfig.S3Config = vfs.S3FsConfig{
+		Bucket:   "s3bucket",
+		Endpoint: "endpoint",
+	}
+	user.FsConfig.GCSConfig = vfs.GCSFsConfig{
+		Bucket: "gcsbucket",
+	}
+	a := newActionNotification(user, operationDownload, "path", "target", "", ProtocolSFTP, 123, errors.New("fake error"))
+	assert.Equal(t, user.Username, a.Username)
+	assert.Equal(t, 0, len(a.Bucket))
+	assert.Equal(t, 0, len(a.Endpoint))
+	assert.Equal(t, 0, a.Status)
+
+	user.FsConfig.Provider = dataprovider.S3FilesystemProvider
+	a = newActionNotification(user, operationDownload, "path", "target", "", ProtocolSSH, 123, nil)
+	assert.Equal(t, "s3bucket", a.Bucket)
+	assert.Equal(t, "endpoint", a.Endpoint)
+	assert.Equal(t, 1, a.Status)
+
+	user.FsConfig.Provider = dataprovider.GCSFilesystemProvider
+	a = newActionNotification(user, operationDownload, "path", "target", "", ProtocolSCP, 123, ErrQuotaExceeded)
+	assert.Equal(t, "gcsbucket", a.Bucket)
+	assert.Equal(t, 0, len(a.Endpoint))
+	assert.Equal(t, 2, a.Status)
+}
+
+func TestActionHTTP(t *testing.T) {
+	actionsCopy := Config.Actions
+
+	Config.Actions = ProtocolActions{
+		ExecuteOn: []string{operationDownload},
+		Hook:      fmt.Sprintf("http://%v", httpAddr),
+	}
+	user := &dataprovider.User{
+		Username: "username",
+	}
+	a := newActionNotification(user, operationDownload, "path", "target", "", ProtocolSFTP, 123, nil)
+	err := a.execute()
+	assert.NoError(t, err)
+
+	Config.Actions.Hook = "http://invalid:1234"
+	err = a.execute()
+	assert.Error(t, err)
+
+	Config.Actions.Hook = fmt.Sprintf("http://%v/404", httpAddr)
+	err = a.execute()
+	if assert.Error(t, err) {
+		assert.EqualError(t, err, errUnexpectedHTTResponse.Error())
+	}
+
+	Config.Actions = actionsCopy
+}
+
+func TestActionCMD(t *testing.T) {
+	if runtime.GOOS == osWindows {
+		t.Skip("this test is not available on Windows")
+	}
+	actionsCopy := Config.Actions
+
+	hookCmd, err := exec.LookPath("true")
+	assert.NoError(t, err)
+
+	Config.Actions = ProtocolActions{
+		ExecuteOn: []string{operationDownload},
+		Hook:      hookCmd,
+	}
+	user := &dataprovider.User{
+		Username: "username",
+	}
+	a := newActionNotification(user, operationDownload, "path", "target", "", ProtocolSFTP, 123, nil)
+	err = a.execute()
+	assert.NoError(t, err)
+
+	SSHCommandActionNotification(user, "path", "target", "sha1sum", nil)
+
+	Config.Actions = actionsCopy
+}
+
+func TestWrongActions(t *testing.T) {
+	actionsCopy := Config.Actions
+
+	badCommand := "/bad/command"
+	if runtime.GOOS == osWindows {
+		badCommand = "C:\\bad\\command"
+	}
+	Config.Actions = ProtocolActions{
+		ExecuteOn: []string{operationUpload},
+		Hook:      badCommand,
+	}
+	user := &dataprovider.User{
+		Username: "username",
+	}
+
+	a := newActionNotification(user, operationUpload, "", "", "", ProtocolSFTP, 123, nil)
+	err := a.execute()
+	assert.Error(t, err, "action with bad command must fail")
+
+	a.Action = operationDelete
+	err = a.execute()
+	assert.EqualError(t, err, errUnconfiguredAction.Error())
+
+	Config.Actions.Hook = "http://foo\x7f.com/"
+	a.Action = operationUpload
+	err = a.execute()
+	assert.Error(t, err, "action with bad url must fail")
+
+	Config.Actions.Hook = ""
+	err = a.execute()
+	if assert.Error(t, err) {
+		assert.EqualError(t, err, errNoHook.Error())
+	}
+
+	Config.Actions.Hook = "relative path"
+	err = a.execute()
+	if assert.Error(t, err) {
+		assert.EqualError(t, err, fmt.Sprintf("invalid notification command %#v", Config.Actions.Hook))
+	}
+
+	Config.Actions = actionsCopy
+}
+
+func TestPreDeleteAction(t *testing.T) {
+	if runtime.GOOS == osWindows {
+		t.Skip("this test is not available on Windows")
+	}
+	actionsCopy := Config.Actions
+
+	hookCmd, err := exec.LookPath("true")
+	assert.NoError(t, err)
+	Config.Actions = ProtocolActions{
+		ExecuteOn: []string{operationPreDelete},
+		Hook:      hookCmd,
+	}
+	homeDir := filepath.Join(os.TempDir(), "test_user")
+	err = os.MkdirAll(homeDir, os.ModePerm)
+	assert.NoError(t, err)
+	user := dataprovider.User{
+		Username: "username",
+		HomeDir:  homeDir,
+	}
+	user.Permissions = make(map[string][]string)
+	user.Permissions["/"] = []string{dataprovider.PermAny}
+	fs := vfs.NewOsFs("id", homeDir, nil)
+	c := NewBaseConnection("id", ProtocolSFTP, user, fs)
+
+	testfile := filepath.Join(user.HomeDir, "testfile")
+	err = ioutil.WriteFile(testfile, []byte("test"), os.ModePerm)
+	assert.NoError(t, err)
+	info, err := os.Stat(testfile)
+	assert.NoError(t, err)
+	err = c.RemoveFile(testfile, "testfile", info)
+	assert.NoError(t, err)
+	assert.FileExists(t, testfile)
+
+	os.RemoveAll(homeDir)
+
+	Config.Actions = actionsCopy
+}

common/common.go

@@ -0,0 +1,749 @@
+// Package common defines code shared among file transfer packages and protocols
+package common
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"net"
+	"net/http"
+	"net/url"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"github.com/pires/go-proxyproto"
+
+	"github.com/drakkan/sftpgo/dataprovider"
+	"github.com/drakkan/sftpgo/httpclient"
+	"github.com/drakkan/sftpgo/logger"
+	"github.com/drakkan/sftpgo/metrics"
+	"github.com/drakkan/sftpgo/utils"
+)
+
+// constants
+const (
+	logSender                = "common"
+	uploadLogSender          = "Upload"
+	downloadLogSender        = "Download"
+	renameLogSender          = "Rename"
+	rmdirLogSender           = "Rmdir"
+	mkdirLogSender           = "Mkdir"
+	symlinkLogSender         = "Symlink"
+	removeLogSender          = "Remove"
+	chownLogSender           = "Chown"
+	chmodLogSender           = "Chmod"
+	chtimesLogSender         = "Chtimes"
+	truncateLogSender        = "Truncate"
+	operationDownload        = "download"
+	operationUpload          = "upload"
+	operationDelete          = "delete"
+	operationPreDelete       = "pre-delete"
+	operationRename          = "rename"
+	operationSSHCmd          = "ssh_cmd"
+	chtimesFormat            = "2006-01-02T15:04:05" // YYYY-MM-DDTHH:MM:SS
+	idleTimeoutCheckInterval = 3 * time.Minute
+)
+
+// Stat flags
+const (
+	StatAttrUIDGID = 1
+	StatAttrPerms  = 2
+	StatAttrTimes  = 4
+	StatAttrSize   = 8
+)
+
+// Transfer types
+const (
+	TransferUpload = iota
+	TransferDownload
+)
+
+// Supported protocols
+const (
+	ProtocolSFTP   = "SFTP"
+	ProtocolSCP    = "SCP"
+	ProtocolSSH    = "SSH"
+	ProtocolFTP    = "FTP"
+	ProtocolWebDAV = "DAV"
+)
+
+// Upload modes
+const (
+	UploadModeStandard = iota
+	UploadModeAtomic
+	UploadModeAtomicWithResume
+)
+
+// errors definitions
+var (
+	ErrPermissionDenied     = errors.New("permission denied")
+	ErrNotExist             = errors.New("no such file or directory")
+	ErrOpUnsupported        = errors.New("operation unsupported")
+	ErrGenericFailure       = errors.New("failure")
+	ErrQuotaExceeded        = errors.New("denying write due to space limit")
+	ErrSkipPermissionsCheck = errors.New("permission check skipped")
+	ErrConnectionDenied     = errors.New("You are not allowed to connect")
+	errNoTransfer           = errors.New("requested transfer not found")
+	errTransferMismatch     = errors.New("transfer mismatch")
+)
+
+var (
+	// Config is the configuration for the supported protocols
+	Config Configuration
+	// Connections is the list of active connections
+	Connections ActiveConnections
+	// QuotaScans is the list of active quota scans
+	QuotaScans            ActiveScans
+	idleTimeoutTicker     *time.Ticker
+	idleTimeoutTickerDone chan bool
+	supportedProtocols    = []string{ProtocolSFTP, ProtocolSCP, ProtocolSSH, ProtocolFTP, ProtocolWebDAV}
+)
+
+// Initialize sets the common configuration
+func Initialize(c Configuration) {
+	Config = c
+	Config.idleLoginTimeout = 2 * time.Minute
+	Config.idleTimeoutAsDuration = time.Duration(Config.IdleTimeout) * time.Minute
+	if Config.IdleTimeout > 0 {
+		startIdleTimeoutTicker(idleTimeoutCheckInterval)
+	}
+}
+
+func startIdleTimeoutTicker(duration time.Duration) {
+	stopIdleTimeoutTicker()
+	idleTimeoutTicker = time.NewTicker(duration)
+	idleTimeoutTickerDone = make(chan bool)
+	go func() {
+		for {
+			select {
+			case <-idleTimeoutTickerDone:
+				return
+			case <-idleTimeoutTicker.C:
+				Connections.checkIdleConnections()
+			}
+		}
+	}()
+}
+
+func stopIdleTimeoutTicker() {
+	if idleTimeoutTicker != nil {
+		idleTimeoutTicker.Stop()
+		idleTimeoutTickerDone <- true
+		idleTimeoutTicker = nil
+	}
+}
+
+// ActiveTransfer defines the interface for the current active transfers
+type ActiveTransfer interface {
+	GetID() uint64
+	GetType() int
+	GetSize() int64
+	GetVirtualPath() string
+	GetStartTime() time.Time
+	SignalClose()
+	Truncate(fsPath string, size int64) (int64, error)
+	GetRealFsPath(fsPath string) string
+}
+
+// ActiveConnection defines the interface for the current active connections
+type ActiveConnection interface {
+	GetID() string
+	GetUsername() string
+	GetRemoteAddress() string
+	GetClientVersion() string
+	GetProtocol() string
+	GetConnectionTime() time.Time
+	GetLastActivity() time.Time
+	GetCommand() string
+	Disconnect() error
+	AddTransfer(t ActiveTransfer)
+	RemoveTransfer(t ActiveTransfer)
+	GetTransfers() []ConnectionTransfer
+}
+
+// StatAttributes defines the attributes for set stat commands
+type StatAttributes struct {
+	Mode  os.FileMode
+	Atime time.Time
+	Mtime time.Time
+	UID   int
+	GID   int
+	Flags int
+	Size  int64
+}
+
+// ConnectionTransfer defines the trasfer details to expose
+type ConnectionTransfer struct {
+	ID            uint64 `json:"-"`
+	OperationType string `json:"operation_type"`
+	StartTime     int64  `json:"start_time"`
+	Size          int64  `json:"size"`
+	VirtualPath   string `json:"path"`
+}
+
+func (t *ConnectionTransfer) getConnectionTransferAsString() string {
+	result := ""
+	switch t.OperationType {
+	case operationUpload:
+		result += "UL "
+	case operationDownload:
+		result += "DL "
+	}
+	result += fmt.Sprintf("%#v ", t.VirtualPath)
+	if t.Size > 0 {
+		elapsed := time.Since(utils.GetTimeFromMsecSinceEpoch(t.StartTime))
+		speed := float64(t.Size) / float64(utils.GetTimeAsMsSinceEpoch(time.Now())-t.StartTime)
+		result += fmt.Sprintf("Size: %#v Elapsed: %#v Speed: \"%.1f KB/s\"", utils.ByteCountSI(t.Size),
+			utils.GetDurationAsString(elapsed), speed)
+	}
+	return result
+}
+
+// Configuration defines configuration parameters common to all supported protocols
+type Configuration struct {
+	// Maximum idle timeout as minutes. If a client is idle for a time that exceeds this setting it will be disconnected.
+	// 0 means disabled
+	IdleTimeout int `json:"idle_timeout" mapstructure:"idle_timeout"`
+	// UploadMode 0 means standard, the files are uploaded directly to the requested path.
+	// 1 means atomic: the files are uploaded to a temporary path and renamed to the requested path
+	// when the client ends the upload. Atomic mode avoid problems such as a web server that
+	// serves partial files when the files are being uploaded.
+	// In atomic mode if there is an upload error the temporary file is deleted and so the requested
+	// upload path will not contain a partial file.
+	// 2 means atomic with resume support: as atomic but if there is an upload error the temporary
+	// file is renamed to the requested path and not deleted, this way a client can reconnect and resume
+	// the upload.
+	UploadMode int `json:"upload_mode" mapstructure:"upload_mode"`
+	// Actions to execute for SFTP file operations and SSH commands
+	Actions ProtocolActions `json:"actions" mapstructure:"actions"`
+	// SetstatMode 0 means "normal mode": requests for changing permissions and owner/group are executed.
+	// 1 means "ignore mode": requests for changing permissions and owner/group are silently ignored.
+	SetstatMode int `json:"setstat_mode" mapstructure:"setstat_mode"`
+	// Support for HAProxy PROXY protocol.
+	// If you are running SFTPGo behind a proxy server such as HAProxy, AWS ELB or NGNIX, you can enable
+	// the proxy protocol. It provides a convenient way to safely transport connection information
+	// such as a client's address across multiple layers of NAT or TCP proxies to get the real
+	// client IP address instead of the proxy IP. Both protocol versions 1 and 2 are supported.
+	// - 0 means disabled
+	// - 1 means proxy protocol enabled. Proxy header will be used and requests without proxy header will be accepted.
+	// - 2 means proxy protocol required. Proxy header will be used and requests without proxy header will be rejected.
+	// If the proxy protocol is enabled in SFTPGo then you have to enable the protocol in your proxy configuration too,
+	// for example for HAProxy add "send-proxy" or "send-proxy-v2" to each server configuration line.
+	ProxyProtocol int `json:"proxy_protocol" mapstructure:"proxy_protocol"`
+	// List of IP addresses and IP ranges allowed to send the proxy header.
+	// If proxy protocol is set to 1 and we receive a proxy header from an IP that is not in the list then the
+	// connection will be accepted and the header will be ignored.
+	// If proxy protocol is set to 2 and we receive a proxy header from an IP that is not in the list then the
+	// connection will be rejected.
+	ProxyAllowed []string `json:"proxy_allowed" mapstructure:"proxy_allowed"`
+	// Absolute path to an external program or an HTTP URL to invoke after a user connects
+	// and before he tries to login. It allows you to reject the connection based on the source
+	// ip address. Leave empty do disable.
+	PostConnectHook       string `json:"post_connect_hook" mapstructure:"post_connect_hook"`
+	idleTimeoutAsDuration time.Duration
+	idleLoginTimeout      time.Duration
+}
+
+// IsAtomicUploadEnabled returns true if atomic upload is enabled
+func (c *Configuration) IsAtomicUploadEnabled() bool {
+	return c.UploadMode == UploadModeAtomic || c.UploadMode == UploadModeAtomicWithResume
+}
+
+// GetProxyListener returns a wrapper for the given listener that supports the
+// HAProxy Proxy Protocol or nil if the proxy protocol is not configured
+func (c *Configuration) GetProxyListener(listener net.Listener) (*proxyproto.Listener, error) {
+	var proxyListener *proxyproto.Listener
+	var err error
+	if c.ProxyProtocol > 0 {
+		var policyFunc func(upstream net.Addr) (proxyproto.Policy, error)
+		if c.ProxyProtocol == 1 && len(c.ProxyAllowed) > 0 {
+			policyFunc, err = proxyproto.LaxWhiteListPolicy(c.ProxyAllowed)
+			if err != nil {
+				return nil, err
+			}
+		}
+		if c.ProxyProtocol == 2 {
+			if len(c.ProxyAllowed) == 0 {
+				policyFunc = func(upstream net.Addr) (proxyproto.Policy, error) {
+					return proxyproto.REQUIRE, nil
+				}
+			} else {
+				policyFunc, err = proxyproto.StrictWhiteListPolicy(c.ProxyAllowed)
+				if err != nil {
+					return nil, err
+				}
+			}
+		}
+		proxyListener = &proxyproto.Listener{
+			Listener: listener,
+			Policy:   policyFunc,
+		}
+	}
+	return proxyListener, nil
+}
+
+// ExecutePostConnectHook executes the post connect hook if defined
+func (c *Configuration) ExecutePostConnectHook(remoteAddr, protocol string) error {
+	if len(c.PostConnectHook) == 0 {
+		return nil
+	}
+	ip := utils.GetIPFromRemoteAddress(remoteAddr)
+	if strings.HasPrefix(c.PostConnectHook, "http") {
+		var url *url.URL
+		url, err := url.Parse(c.PostConnectHook)
+		if err != nil {
+			logger.Warn(protocol, "", "Login from ip %#v denied, invalid post connect hook %#v: %v",
+				ip, c.PostConnectHook, err)
+			return err
+		}
+		httpClient := httpclient.GetHTTPClient()
+		q := url.Query()
+		q.Add("ip", ip)
+		q.Add("protocol", protocol)
+		url.RawQuery = q.Encode()
+
+		resp, err := httpClient.Get(url.String())
+		if err != nil {
+			logger.Warn(protocol, "", "Login from ip %#v denied, error executing post connect hook: %v", ip, err)
+			return err
+		}
+		defer resp.Body.Close()
+		if resp.StatusCode != http.StatusOK {
+			logger.Warn(protocol, "", "Login from ip %#v denied, post connect hook response code: %v", ip, resp.StatusCode)
+			return errUnexpectedHTTResponse
+		}
+		return nil
+	}
+	if !filepath.IsAbs(c.PostConnectHook) {
+		err := fmt.Errorf("invalid post connect hook %#v", c.PostConnectHook)
+		logger.Warn(protocol, "", "Login from ip %#v denied: %v", ip, err)
+		return err
+	}
+	ctx, cancel := context.WithTimeout(context.Background(), 20*time.Second)
+	defer cancel()
+	cmd := exec.CommandContext(ctx, c.PostConnectHook)
+	cmd.Env = append(os.Environ(),
+		fmt.Sprintf("SFTPGO_CONNECTION_IP=%v", ip),
+		fmt.Sprintf("SFTPGO_CONNECTION_PROTOCOL=%v", protocol))
+	err := cmd.Run()
+	if err != nil {
+		logger.Warn(protocol, "", "Login from ip %#v denied, connect hook error: %v", ip, err)
+	}
+	return err
+}
+
+// SSHConnection defines an ssh connection.
+// Each SSH connection can open several channels for SFTP or SSH commands
+type SSHConnection struct {
+	id           string
+	conn         net.Conn
+	lastActivity int64
+}
+
+// NewSSHConnection returns a new SSHConnection
+func NewSSHConnection(id string, conn net.Conn) *SSHConnection {
+	return &SSHConnection{
+		id:           id,
+		conn:         conn,
+		lastActivity: time.Now().UnixNano(),
+	}
+}
+
+// GetID returns the ID for this SSHConnection
+func (c *SSHConnection) GetID() string {
+	return c.id
+}
+
+// UpdateLastActivity updates last activity for this connection
+func (c *SSHConnection) UpdateLastActivity() {
+	atomic.StoreInt64(&c.lastActivity, time.Now().UnixNano())
+}
+
+// GetLastActivity returns the last connection activity
+func (c *SSHConnection) GetLastActivity() time.Time {
+	return time.Unix(0, atomic.LoadInt64(&c.lastActivity))
+}
+
+// Close closes the underlying network connection
+func (c *SSHConnection) Close() error {
+	return c.conn.Close()
+}
+
+// ActiveConnections holds the currect active connections with the associated transfers
+type ActiveConnections struct {
+	sync.RWMutex
+	connections    []ActiveConnection
+	sshConnections []*SSHConnection
+}
+
+// GetActiveSessions returns the number of active sessions for the given username.
+// We return the open sessions for any protocol
+func (conns *ActiveConnections) GetActiveSessions(username string) int {
+	conns.RLock()
+	defer conns.RUnlock()
+
+	numSessions := 0
+	for _, c := range conns.connections {
+		if c.GetUsername() == username {
+			numSessions++
+		}
+	}
+	return numSessions
+}
+
+// Add adds a new connection to the active ones
+func (conns *ActiveConnections) Add(c ActiveConnection) {
+	conns.Lock()
+	defer conns.Unlock()
+
+	conns.connections = append(conns.connections, c)
+	metrics.UpdateActiveConnectionsSize(len(conns.connections))
+	logger.Debug(c.GetProtocol(), c.GetID(), "connection added, num open connections: %v", len(conns.connections))
+}
+
+// Swap replaces an existing connection with the given one.
+// This method is useful if you have to change some connection details
+// for example for FTP is used to update the connection once the user
+// authenticates
+func (conns *ActiveConnections) Swap(c ActiveConnection) error {
+	conns.Lock()
+	defer conns.Unlock()
+
+	for idx, conn := range conns.connections {
+		if conn.GetID() == c.GetID() {
+			conn = nil
+			conns.connections[idx] = c
+			return nil
+		}
+	}
+	return errors.New("connection to swap not found")
+}
+
+// Remove removes a connection from the active ones
+func (conns *ActiveConnections) Remove(connectionID string) {
+	conns.Lock()
+	defer conns.Unlock()
+
+	var c ActiveConnection
+	indexToRemove := -1
+	for i, conn := range conns.connections {
+		if conn.GetID() == connectionID {
+			indexToRemove = i
+			c = conn
+			break
+		}
+	}
+	if indexToRemove >= 0 {
+		conns.connections[indexToRemove] = conns.connections[len(conns.connections)-1]
+		conns.connections[len(conns.connections)-1] = nil
+		conns.connections = conns.connections[:len(conns.connections)-1]
+		metrics.UpdateActiveConnectionsSize(len(conns.connections))
+		logger.Debug(c.GetProtocol(), c.GetID(), "connection removed, num open connections: %v", len(conns.connections))
+	} else {
+		logger.Warn(logSender, "", "connection to remove with id %#v not found!", connectionID)
+	}
+}
+
+// Close closes an active connection.
+// It returns true on success
+func (conns *ActiveConnections) Close(connectionID string) bool {
+	conns.RLock()
+	result := false
+
+	for _, c := range conns.connections {
+		if c.GetID() == connectionID {
+			defer func(conn ActiveConnection) {
+				err := conn.Disconnect()
+				logger.Debug(conn.GetProtocol(), conn.GetID(), "close connection requested, close err: %v", err)
+			}(c)
+			result = true
+			break
+		}
+	}
+
+	conns.RUnlock()
+	return result
+}
+
+// AddSSHConnection adds a new ssh connection to the active ones
+func (conns *ActiveConnections) AddSSHConnection(c *SSHConnection) {
+	conns.Lock()
+	defer conns.Unlock()
+
+	conns.sshConnections = append(conns.sshConnections, c)
+	logger.Debug(logSender, c.GetID(), "ssh connection added, num open connections: %v", len(conns.sshConnections))
+}
+
+// RemoveSSHConnection removes a connection from the active ones
+func (conns *ActiveConnections) RemoveSSHConnection(connectionID string) {
+	conns.Lock()
+	defer conns.Unlock()
+
+	var c *SSHConnection
+	indexToRemove := -1
+	for i, conn := range conns.sshConnections {
+		if conn.GetID() == connectionID {
+			indexToRemove = i
+			c = conn
+			break
+		}
+	}
+	if indexToRemove >= 0 {
+		conns.sshConnections[indexToRemove] = conns.sshConnections[len(conns.sshConnections)-1]
+		conns.sshConnections[len(conns.sshConnections)-1] = nil
+		conns.sshConnections = conns.sshConnections[:len(conns.sshConnections)-1]
+		logger.Debug(logSender, c.GetID(), "ssh connection removed, num open ssh connections: %v", len(conns.sshConnections))
+	} else {
+		logger.Warn(logSender, "", "ssh connection to remove with id %#v not found!", connectionID)
+	}
+}
+
+func (conns *ActiveConnections) checkIdleConnections() {
+	conns.RLock()
+
+	for _, sshConn := range conns.sshConnections {
+		idleTime := time.Since(sshConn.GetLastActivity())
+		if idleTime > Config.idleTimeoutAsDuration {
+			// we close the an ssh connection if it has no active connections associated
+			idToMatch := fmt.Sprintf("_%v_", sshConn.GetID())
+			toClose := true
+			for _, conn := range conns.connections {
+				if strings.Contains(conn.GetID(), idToMatch) {
+					toClose = false
+					break
+				}
+			}
+			if toClose {
+				defer func(c *SSHConnection) {
+					err := c.Close()
+					logger.Debug(logSender, c.GetID(), "close idle SSH connection, idle time: %v, close err: %v",
+						time.Since(c.GetLastActivity()), err)
+				}(sshConn)
+			}
+		}
+	}
+
+	for _, c := range conns.connections {
+		idleTime := time.Since(c.GetLastActivity())
+		isUnauthenticatedFTPUser := (c.GetProtocol() == ProtocolFTP && len(c.GetUsername()) == 0)
+
+		if idleTime > Config.idleTimeoutAsDuration || (isUnauthenticatedFTPUser && idleTime > Config.idleLoginTimeout) {
+			defer func(conn ActiveConnection, isFTPNoAuth bool) {
+				err := conn.Disconnect()
+				logger.Debug(conn.GetProtocol(), conn.GetID(), "close idle connection, idle time: %v, username: %#v close err: %v",
+					time.Since(conn.GetLastActivity()), conn.GetUsername(), err)
+				if isFTPNoAuth {
+					ip := utils.GetIPFromRemoteAddress(c.GetRemoteAddress())
+					logger.ConnectionFailedLog("", ip, dataprovider.LoginMethodNoAuthTryed, c.GetProtocol(), "client idle")
+					metrics.AddNoAuthTryed()
+					dataprovider.ExecutePostLoginHook("", dataprovider.LoginMethodNoAuthTryed, ip, c.GetProtocol(),
+						dataprovider.ErrNoAuthTryed)
+				}
+			}(c, isUnauthenticatedFTPUser)
+		}
+	}
+
+	conns.RUnlock()
+}
+
+// GetStats returns stats for active connections
+func (conns *ActiveConnections) GetStats() []ConnectionStatus {
+	conns.RLock()
+	defer conns.RUnlock()
+
+	stats := make([]ConnectionStatus, 0, len(conns.connections))
+	for _, c := range conns.connections {
+		stat := ConnectionStatus{
+			Username:       c.GetUsername(),
+			ConnectionID:   c.GetID(),
+			ClientVersion:  c.GetClientVersion(),
+			RemoteAddress:  c.GetRemoteAddress(),
+			ConnectionTime: utils.GetTimeAsMsSinceEpoch(c.GetConnectionTime()),
+			LastActivity:   utils.GetTimeAsMsSinceEpoch(c.GetLastActivity()),
+			Protocol:       c.GetProtocol(),
+			Command:        c.GetCommand(),
+			Transfers:      c.GetTransfers(),
+		}
+		stats = append(stats, stat)
+	}
+	return stats
+}
+
+// ConnectionStatus returns the status for an active connection
+type ConnectionStatus struct {
+	// Logged in username
+	Username string `json:"username"`
+	// Unique identifier for the connection
+	ConnectionID string `json:"connection_id"`
+	// client's version string
+	ClientVersion string `json:"client_version,omitempty"`
+	// Remote address for this connection
+	RemoteAddress string `json:"remote_address"`
+	// Connection time as unix timestamp in milliseconds
+	ConnectionTime int64 `json:"connection_time"`
+	// Last activity as unix timestamp in milliseconds
+	LastActivity int64 `json:"last_activity"`
+	// Protocol for this connection
+	Protocol string `json:"protocol"`
+	// active uploads/downloads
+	Transfers []ConnectionTransfer `json:"active_transfers,omitempty"`
+	// SSH command or WevDAV method
+	Command string `json:"command,omitempty"`
+}
+
+// GetConnectionDuration returns the connection duration as string
+func (c ConnectionStatus) GetConnectionDuration() string {
+	elapsed := time.Since(utils.GetTimeFromMsecSinceEpoch(c.ConnectionTime))
+	return utils.GetDurationAsString(elapsed)
+}
+
+// GetConnectionInfo returns connection info.
+// Protocol,Client Version and RemoteAddress are returned.
+// For SSH commands the issued command is returned too.
+func (c ConnectionStatus) GetConnectionInfo() string {
+	result := fmt.Sprintf("%v. Client: %#v From: %#v", c.Protocol, c.ClientVersion, c.RemoteAddress)
+	if c.Protocol == ProtocolSSH && len(c.Command) > 0 {
+		result += fmt.Sprintf(". Command: %#v", c.Command)
+	}
+	if c.Protocol == ProtocolWebDAV && len(c.Command) > 0 {
+		result += fmt.Sprintf(". Method: %#v", c.Command)
+	}
+	return result
+}
+
+// GetTransfersAsString returns the active transfers as string
+func (c ConnectionStatus) GetTransfersAsString() string {
+	result := ""
+	for _, t := range c.Transfers {
+		if len(result) > 0 {
+			result += ". "
+		}
+		result += t.getConnectionTransferAsString()
+	}
+	return result
+}
+
+// ActiveQuotaScan defines an active quota scan for a user home dir
+type ActiveQuotaScan struct {
+	// Username to which the quota scan refers
+	Username string `json:"username"`
+	// quota scan start time as unix timestamp in milliseconds
+	StartTime int64 `json:"start_time"`
+}
+
+// ActiveVirtualFolderQuotaScan defines an active quota scan for a virtual folder
+type ActiveVirtualFolderQuotaScan struct {
+	// folder path to which the quota scan refers
+	MappedPath string `json:"mapped_path"`
+	// quota scan start time as unix timestamp in milliseconds
+	StartTime int64 `json:"start_time"`
+}
+
+// ActiveScans holds the active quota scans
+type ActiveScans struct {
+	sync.RWMutex
+	UserHomeScans []ActiveQuotaScan
+	FolderScans   []ActiveVirtualFolderQuotaScan
+}
+
+// GetUsersQuotaScans returns the active quota scans for users home directories
+func (s *ActiveScans) GetUsersQuotaScans() []ActiveQuotaScan {
+	s.RLock()
+	defer s.RUnlock()
+
+	scans := make([]ActiveQuotaScan, len(s.UserHomeScans))
+	copy(scans, s.UserHomeScans)
+	return scans
+}
+
+// AddUserQuotaScan adds a user to the ones with active quota scans.
+// Returns false if the user has a quota scan already running
+func (s *ActiveScans) AddUserQuotaScan(username string) bool {
+	s.Lock()
+	defer s.Unlock()
+
+	for _, scan := range s.UserHomeScans {
+		if scan.Username == username {
+			return false
+		}
+	}
+	s.UserHomeScans = append(s.UserHomeScans, ActiveQuotaScan{
+		Username:  username,
+		StartTime: utils.GetTimeAsMsSinceEpoch(time.Now()),
+	})
+	return true
+}
+
+// RemoveUserQuotaScan removes a user from the ones with active quota scans.
+// Returns false if the user has no active quota scans
+func (s *ActiveScans) RemoveUserQuotaScan(username string) bool {
+	s.Lock()
+	defer s.Unlock()
+
+	indexToRemove := -1
+	for i, scan := range s.UserHomeScans {
+		if scan.Username == username {
+			indexToRemove = i
+			break
+		}
+	}
+	if indexToRemove >= 0 {
+		s.UserHomeScans[indexToRemove] = s.UserHomeScans[len(s.UserHomeScans)-1]
+		s.UserHomeScans = s.UserHomeScans[:len(s.UserHomeScans)-1]
+		return true
+	}
+	return false
+}
+
+// GetVFoldersQuotaScans returns the active quota scans for virtual folders
+func (s *ActiveScans) GetVFoldersQuotaScans() []ActiveVirtualFolderQuotaScan {
+	s.RLock()
+	defer s.RUnlock()
+	scans := make([]ActiveVirtualFolderQuotaScan, len(s.FolderScans))
+	copy(scans, s.FolderScans)
+	return scans
+}
+
+// AddVFolderQuotaScan adds a virtual folder to the ones with active quota scans.
+// Returns false if the folder has a quota scan already running
+func (s *ActiveScans) AddVFolderQuotaScan(folderPath string) bool {
+	s.Lock()
+	defer s.Unlock()
+
+	for _, scan := range s.FolderScans {
+		if scan.MappedPath == folderPath {
+			return false
+		}
+	}
+	s.FolderScans = append(s.FolderScans, ActiveVirtualFolderQuotaScan{
+		MappedPath: folderPath,
+		StartTime:  utils.GetTimeAsMsSinceEpoch(time.Now()),
+	})
+	return true
+}
+
+// RemoveVFolderQuotaScan removes a folder from the ones with active quota scans.
+// Returns false if the folder has no active quota scans
+func (s *ActiveScans) RemoveVFolderQuotaScan(folderPath string) bool {
+	s.Lock()
+	defer s.Unlock()
+
+	indexToRemove := -1
+	for i, scan := range s.FolderScans {
+		if scan.MappedPath == folderPath {
+			indexToRemove = i
+			break
+		}
+	}
+	if indexToRemove >= 0 {
+		s.FolderScans[indexToRemove] = s.FolderScans[len(s.FolderScans)-1]
+		s.FolderScans = s.FolderScans[:len(s.FolderScans)-1]
+		return true
+	}
+	return false
+}

common/common_test.go

@@ -0,0 +1,516 @@
+package common
+
+import (
+	"fmt"
+	"net"
+	"net/http"
+	"os"
+	"os/exec"
+	"runtime"
+	"strings"
+	"sync/atomic"
+	"testing"
+	"time"
+
+	"github.com/rs/zerolog"
+	"github.com/spf13/viper"
+	"github.com/stretchr/testify/assert"
+
+	"github.com/drakkan/sftpgo/dataprovider"
+	"github.com/drakkan/sftpgo/httpclient"
+	"github.com/drakkan/sftpgo/logger"
+	"github.com/drakkan/sftpgo/vfs"
+)
+
+const (
+	logSenderTest    = "common_test"
+	httpAddr         = "127.0.0.1:9999"
+	httpProxyAddr    = "127.0.0.1:7777"
+	configDir        = ".."
+	osWindows        = "windows"
+	userTestUsername = "common_test_username"
+	userTestPwd      = "common_test_pwd"
+)
+
+type providerConf struct {
+	Config dataprovider.Config `json:"data_provider" mapstructure:"data_provider"`
+}
+
+type fakeConnection struct {
+	*BaseConnection
+	command string
+}
+
+func (c *fakeConnection) AddUser(user dataprovider.User) error {
+	fs, err := user.GetFilesystem(c.GetID())
+	if err != nil {
+		return err
+	}
+	c.BaseConnection.User = user
+	c.BaseConnection.Fs = fs
+	return nil
+}
+
+func (c *fakeConnection) Disconnect() error {
+	Connections.Remove(c.GetID())
+	return nil
+}
+
+func (c *fakeConnection) GetClientVersion() string {
+	return ""
+}
+
+func (c *fakeConnection) GetCommand() string {
+	return c.command
+}
+
+func (c *fakeConnection) GetRemoteAddress() string {
+	return ""
+}
+
+type customNetConn struct {
+	net.Conn
+	id       string
+	isClosed bool
+}
+
+func (c *customNetConn) Close() error {
+	Connections.RemoveSSHConnection(c.id)
+	c.isClosed = true
+	return c.Conn.Close()
+}
+
+func TestMain(m *testing.M) {
+	logfilePath := "common_test.log"
+	logger.InitLogger(logfilePath, 5, 1, 28, false, zerolog.DebugLevel)
+
+	viper.SetEnvPrefix("sftpgo")
+	replacer := strings.NewReplacer(".", "__")
+	viper.SetEnvKeyReplacer(replacer)
+	viper.SetConfigName("sftpgo")
+	viper.AutomaticEnv()
+	viper.AllowEmptyEnv(true)
+
+	driver, err := initializeDataprovider(-1)
+	if err != nil {
+		logger.WarnToConsole("error initializing data provider: %v", err)
+		os.Exit(1)
+	}
+	logger.InfoToConsole("Starting COMMON tests, provider: %v", driver)
+	Initialize(Configuration{})
+	httpConfig := httpclient.Config{
+		Timeout: 5,
+	}
+	httpConfig.Initialize(configDir)
+
+	go func() {
+		// start a test HTTP server to receive action notifications
+		http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+			fmt.Fprintf(w, "OK\n")
+		})
+		http.HandleFunc("/404", func(w http.ResponseWriter, r *http.Request) {
+			w.WriteHeader(http.StatusNotFound)
+			fmt.Fprintf(w, "Not found\n")
+		})
+		if err := http.ListenAndServe(httpAddr, nil); err != nil {
+			logger.ErrorToConsole("could not start HTTP notification server: %v", err)
+			os.Exit(1)
+		}
+	}()
+
+	go func() {
+		Config.ProxyProtocol = 2
+		listener, err := net.Listen("tcp", httpProxyAddr)
+		if err != nil {
+			logger.ErrorToConsole("error creating listener for proxy protocol server: %v", err)
+			os.Exit(1)
+		}
+		proxyListener, err := Config.GetProxyListener(listener)
+		if err != nil {
+			logger.ErrorToConsole("error creating proxy protocol listener: %v", err)
+			os.Exit(1)
+		}
+		Config.ProxyProtocol = 0
+
+		s := &http.Server{}
+		if err := s.Serve(proxyListener); err != nil {
+			logger.ErrorToConsole("could not start HTTP proxy protocol server: %v", err)
+			os.Exit(1)
+		}
+	}()
+
+	waitTCPListening(httpAddr)
+	waitTCPListening(httpProxyAddr)
+	exitCode := m.Run()
+	os.Remove(logfilePath) //nolint:errcheck
+	os.Exit(exitCode)
+}
+
+func waitTCPListening(address string) {
+	for {
+		conn, err := net.Dial("tcp", address)
+		if err != nil {
+			logger.WarnToConsole("tcp server %v not listening: %v\n", address, err)
+			time.Sleep(100 * time.Millisecond)
+			continue
+		}
+		logger.InfoToConsole("tcp server %v now listening\n", address)
+		conn.Close()
+		break
+	}
+}
+
+func initializeDataprovider(trackQuota int) (string, error) {
+	configDir := ".."
+	viper.AddConfigPath(configDir)
+	if err := viper.ReadInConfig(); err != nil {
+		return "", err
+	}
+	var cfg providerConf
+	if err := viper.Unmarshal(&cfg); err != nil {
+		return "", err
+	}
+	if trackQuota >= 0 && trackQuota <= 2 {
+		cfg.Config.TrackQuota = trackQuota
+	}
+	return cfg.Config.Driver, dataprovider.Initialize(cfg.Config, configDir)
+}
+
+func closeDataprovider() error {
+	return dataprovider.Close()
+}
+
+func TestSSHConnections(t *testing.T) {
+	conn1, conn2 := net.Pipe()
+	now := time.Now()
+	sshConn1 := NewSSHConnection("id1", conn1)
+	sshConn2 := NewSSHConnection("id2", conn2)
+	assert.Equal(t, "id1", sshConn1.GetID())
+	assert.Equal(t, "id2", sshConn2.GetID())
+	sshConn1.UpdateLastActivity()
+	assert.GreaterOrEqual(t, sshConn1.GetLastActivity().UnixNano(), now.UnixNano())
+	Connections.AddSSHConnection(sshConn1)
+	Connections.AddSSHConnection(sshConn2)
+	Connections.RLock()
+	assert.Len(t, Connections.sshConnections, 2)
+	Connections.RUnlock()
+	Connections.RemoveSSHConnection(sshConn1.id)
+	Connections.RLock()
+	assert.Len(t, Connections.sshConnections, 1)
+	Connections.RUnlock()
+	Connections.RemoveSSHConnection(sshConn1.id)
+	Connections.RLock()
+	assert.Len(t, Connections.sshConnections, 1)
+	Connections.RUnlock()
+	Connections.RemoveSSHConnection(sshConn2.id)
+	Connections.RLock()
+	assert.Len(t, Connections.sshConnections, 0)
+	Connections.RUnlock()
+	assert.NoError(t, sshConn1.Close())
+	assert.NoError(t, sshConn2.Close())
+}
+
+func TestIdleConnections(t *testing.T) {
+	configCopy := Config
+
+	Config.IdleTimeout = 1
+	Initialize(Config)
+
+	conn1, conn2 := net.Pipe()
+	customConn1 := &customNetConn{
+		Conn: conn1,
+		id:   "id1",
+	}
+	customConn2 := &customNetConn{
+		Conn: conn2,
+		id:   "id2",
+	}
+	sshConn1 := NewSSHConnection(customConn1.id, customConn1)
+	sshConn2 := NewSSHConnection(customConn2.id, customConn2)
+
+	username := "test_user"
+	user := dataprovider.User{
+		Username: username,
+	}
+	c := NewBaseConnection(sshConn1.id+"_1", ProtocolSFTP, user, nil)
+	c.lastActivity = time.Now().Add(-24 * time.Hour).UnixNano()
+	fakeConn := &fakeConnection{
+		BaseConnection: c,
+	}
+	// both ssh connections are expired but they should get removed only
+	// if there is no associated connection
+	sshConn1.lastActivity = c.lastActivity
+	sshConn2.lastActivity = c.lastActivity
+	Connections.AddSSHConnection(sshConn1)
+	Connections.Add(fakeConn)
+	assert.Equal(t, Connections.GetActiveSessions(username), 1)
+	c = NewBaseConnection(sshConn2.id+"_1", ProtocolSSH, user, nil)
+	fakeConn = &fakeConnection{
+		BaseConnection: c,
+	}
+	Connections.AddSSHConnection(sshConn2)
+	Connections.Add(fakeConn)
+	assert.Equal(t, Connections.GetActiveSessions(username), 2)
+
+	cFTP := NewBaseConnection("id2", ProtocolFTP, dataprovider.User{}, nil)
+	cFTP.lastActivity = time.Now().UnixNano()
+	fakeConn = &fakeConnection{
+		BaseConnection: cFTP,
+	}
+	Connections.Add(fakeConn)
+	assert.Equal(t, Connections.GetActiveSessions(username), 2)
+	assert.Len(t, Connections.GetStats(), 3)
+	Connections.RLock()
+	assert.Len(t, Connections.sshConnections, 2)
+	Connections.RUnlock()
+
+	startIdleTimeoutTicker(100 * time.Millisecond)
+	assert.Eventually(t, func() bool { return Connections.GetActiveSessions(username) == 1 }, 1*time.Second, 200*time.Millisecond)
+	assert.Eventually(t, func() bool {
+		Connections.RLock()
+		defer Connections.RUnlock()
+		return len(Connections.sshConnections) == 1
+	}, 1*time.Second, 200*time.Millisecond)
+	stopIdleTimeoutTicker()
+	assert.Len(t, Connections.GetStats(), 2)
+	c.lastActivity = time.Now().Add(-24 * time.Hour).UnixNano()
+	cFTP.lastActivity = time.Now().Add(-24 * time.Hour).UnixNano()
+	sshConn2.lastActivity = c.lastActivity
+	startIdleTimeoutTicker(100 * time.Millisecond)
+	assert.Eventually(t, func() bool { return len(Connections.GetStats()) == 0 }, 1*time.Second, 200*time.Millisecond)
+	assert.Eventually(t, func() bool {
+		Connections.RLock()
+		defer Connections.RUnlock()
+		return len(Connections.sshConnections) == 0
+	}, 1*time.Second, 200*time.Millisecond)
+	stopIdleTimeoutTicker()
+	assert.True(t, customConn1.isClosed)
+	assert.True(t, customConn2.isClosed)
+
+	Config = configCopy
+}
+
+func TestCloseConnection(t *testing.T) {
+	c := NewBaseConnection("id", ProtocolSFTP, dataprovider.User{}, nil)
+	fakeConn := &fakeConnection{
+		BaseConnection: c,
+	}
+	Connections.Add(fakeConn)
+	assert.Len(t, Connections.GetStats(), 1)
+	res := Connections.Close(fakeConn.GetID())
+	assert.True(t, res)
+	assert.Eventually(t, func() bool { return len(Connections.GetStats()) == 0 }, 300*time.Millisecond, 50*time.Millisecond)
+	res = Connections.Close(fakeConn.GetID())
+	assert.False(t, res)
+	Connections.Remove(fakeConn.GetID())
+}
+
+func TestSwapConnection(t *testing.T) {
+	c := NewBaseConnection("id", ProtocolFTP, dataprovider.User{}, nil)
+	fakeConn := &fakeConnection{
+		BaseConnection: c,
+	}
+	Connections.Add(fakeConn)
+	if assert.Len(t, Connections.GetStats(), 1) {
+		assert.Equal(t, "", Connections.GetStats()[0].Username)
+	}
+	c = NewBaseConnection("id", ProtocolFTP, dataprovider.User{
+		Username: userTestUsername,
+	}, nil)
+	fakeConn = &fakeConnection{
+		BaseConnection: c,
+	}
+	err := Connections.Swap(fakeConn)
+	assert.NoError(t, err)
+	if assert.Len(t, Connections.GetStats(), 1) {
+		assert.Equal(t, userTestUsername, Connections.GetStats()[0].Username)
+	}
+	res := Connections.Close(fakeConn.GetID())
+	assert.True(t, res)
+	assert.Eventually(t, func() bool { return len(Connections.GetStats()) == 0 }, 300*time.Millisecond, 50*time.Millisecond)
+	err = Connections.Swap(fakeConn)
+	assert.Error(t, err)
+}
+
+func TestAtomicUpload(t *testing.T) {
+	configCopy := Config
+
+	Config.UploadMode = UploadModeStandard
+	assert.False(t, Config.IsAtomicUploadEnabled())
+	Config.UploadMode = UploadModeAtomic
+	assert.True(t, Config.IsAtomicUploadEnabled())
+	Config.UploadMode = UploadModeAtomicWithResume
+	assert.True(t, Config.IsAtomicUploadEnabled())
+
+	Config = configCopy
+}
+
+func TestConnectionStatus(t *testing.T) {
+	username := "test_user"
+	user := dataprovider.User{
+		Username: username,
+	}
+	fs := vfs.NewOsFs("", os.TempDir(), nil)
+	c1 := NewBaseConnection("id1", ProtocolSFTP, user, fs)
+	fakeConn1 := &fakeConnection{
+		BaseConnection: c1,
+	}
+	t1 := NewBaseTransfer(nil, c1, nil, "/p1", "/r1", TransferUpload, 0, 0, 0, true, fs)
+	t1.BytesReceived = 123
+	t2 := NewBaseTransfer(nil, c1, nil, "/p2", "/r2", TransferDownload, 0, 0, 0, true, fs)
+	t2.BytesSent = 456
+	c2 := NewBaseConnection("id2", ProtocolSSH, user, nil)
+	fakeConn2 := &fakeConnection{
+		BaseConnection: c2,
+		command:        "md5sum",
+	}
+	c3 := NewBaseConnection("id3", ProtocolWebDAV, user, nil)
+	fakeConn3 := &fakeConnection{
+		BaseConnection: c3,
+		command:        "PROPFIND",
+	}
+	t3 := NewBaseTransfer(nil, c3, nil, "/p2", "/r2", TransferDownload, 0, 0, 0, true, fs)
+	Connections.Add(fakeConn1)
+	Connections.Add(fakeConn2)
+	Connections.Add(fakeConn3)
+
+	stats := Connections.GetStats()
+	assert.Len(t, stats, 3)
+	for _, stat := range stats {
+		assert.Equal(t, stat.Username, username)
+		assert.True(t, strings.HasPrefix(stat.GetConnectionInfo(), stat.Protocol))
+		assert.True(t, strings.HasPrefix(stat.GetConnectionDuration(), "00:"))
+		if stat.ConnectionID == "SFTP_id1" {
+			assert.Len(t, stat.Transfers, 2)
+			assert.Greater(t, len(stat.GetTransfersAsString()), 0)
+			for _, tr := range stat.Transfers {
+				if tr.OperationType == operationDownload {
+					assert.True(t, strings.HasPrefix(tr.getConnectionTransferAsString(), "DL"))
+				} else if tr.OperationType == operationUpload {
+					assert.True(t, strings.HasPrefix(tr.getConnectionTransferAsString(), "UL"))
+				}
+			}
+		} else if stat.ConnectionID == "DAV_id3" {
+			assert.Len(t, stat.Transfers, 1)
+			assert.Greater(t, len(stat.GetTransfersAsString()), 0)
+		} else {
+			assert.Equal(t, 0, len(stat.GetTransfersAsString()))
+		}
+	}
+
+	err := t1.Close()
+	assert.NoError(t, err)
+	err = t2.Close()
+	assert.NoError(t, err)
+
+	err = fakeConn3.SignalTransfersAbort()
+	assert.NoError(t, err)
+	assert.Equal(t, int32(1), atomic.LoadInt32(&t3.AbortTransfer))
+	err = t3.Close()
+	assert.NoError(t, err)
+	err = fakeConn3.SignalTransfersAbort()
+	assert.Error(t, err)
+
+	Connections.Remove(fakeConn1.GetID())
+	Connections.Remove(fakeConn2.GetID())
+	Connections.Remove(fakeConn3.GetID())
+	stats = Connections.GetStats()
+	assert.Len(t, stats, 0)
+}
+
+func TestQuotaScans(t *testing.T) {
+	username := "username"
+	assert.True(t, QuotaScans.AddUserQuotaScan(username))
+	assert.False(t, QuotaScans.AddUserQuotaScan(username))
+	if assert.Len(t, QuotaScans.GetUsersQuotaScans(), 1) {
+		assert.Equal(t, QuotaScans.GetUsersQuotaScans()[0].Username, username)
+	}
+
+	assert.True(t, QuotaScans.RemoveUserQuotaScan(username))
+	assert.False(t, QuotaScans.RemoveUserQuotaScan(username))
+	assert.Len(t, QuotaScans.GetUsersQuotaScans(), 0)
+
+	folderName := "/folder"
+	assert.True(t, QuotaScans.AddVFolderQuotaScan(folderName))
+	assert.False(t, QuotaScans.AddVFolderQuotaScan(folderName))
+	if assert.Len(t, QuotaScans.GetVFoldersQuotaScans(), 1) {
+		assert.Equal(t, QuotaScans.GetVFoldersQuotaScans()[0].MappedPath, folderName)
+	}
+
+	assert.True(t, QuotaScans.RemoveVFolderQuotaScan(folderName))
+	assert.False(t, QuotaScans.RemoveVFolderQuotaScan(folderName))
+	assert.Len(t, QuotaScans.GetVFoldersQuotaScans(), 0)
+}
+
+func TestProxyProtocolVersion(t *testing.T) {
+	c := Configuration{
+		ProxyProtocol: 1,
+	}
+	proxyListener, err := c.GetProxyListener(nil)
+	assert.NoError(t, err)
+	assert.Nil(t, proxyListener.Policy)
+
+	c.ProxyProtocol = 2
+	proxyListener, err = c.GetProxyListener(nil)
+	assert.NoError(t, err)
+	assert.NotNil(t, proxyListener.Policy)
+
+	c.ProxyProtocol = 1
+	c.ProxyAllowed = []string{"invalid"}
+	_, err = c.GetProxyListener(nil)
+	assert.Error(t, err)
+
+	c.ProxyProtocol = 2
+	_, err = c.GetProxyListener(nil)
+	assert.Error(t, err)
+}
+
+func TestProxyProtocol(t *testing.T) {
+	httpClient := httpclient.GetHTTPClient()
+	resp, err := httpClient.Get(fmt.Sprintf("http://%v", httpProxyAddr))
+	if assert.NoError(t, err) {
+		defer resp.Body.Close()
+		assert.Equal(t, http.StatusBadRequest, resp.StatusCode)
+	}
+}
+
+func TestPostConnectHook(t *testing.T) {
+	Config.PostConnectHook = ""
+
+	remoteAddr := &net.IPAddr{
+		IP:   net.ParseIP("127.0.0.1"),
+		Zone: "",
+	}
+
+	assert.NoError(t, Config.ExecutePostConnectHook(remoteAddr.String(), ProtocolFTP))
+
+	Config.PostConnectHook = "http://foo\x7f.com/"
+	assert.Error(t, Config.ExecutePostConnectHook(remoteAddr.String(), ProtocolSFTP))
+
+	Config.PostConnectHook = "http://invalid:1234/"
+	assert.Error(t, Config.ExecutePostConnectHook(remoteAddr.String(), ProtocolSFTP))
+
+	Config.PostConnectHook = fmt.Sprintf("http://%v/404", httpAddr)
+	assert.Error(t, Config.ExecutePostConnectHook(remoteAddr.String(), ProtocolFTP))
+
+	Config.PostConnectHook = fmt.Sprintf("http://%v", httpAddr)
+	assert.NoError(t, Config.ExecutePostConnectHook(remoteAddr.String(), ProtocolFTP))
+
+	Config.PostConnectHook = "invalid"
+	assert.Error(t, Config.ExecutePostConnectHook(remoteAddr.String(), ProtocolFTP))
+
+	if runtime.GOOS == osWindows {
+		Config.PostConnectHook = "C:\\bad\\command"
+		assert.Error(t, Config.ExecutePostConnectHook(remoteAddr.String(), ProtocolSFTP))
+	} else {
+		Config.PostConnectHook = "/invalid/path"
+		assert.Error(t, Config.ExecutePostConnectHook(remoteAddr.String(), ProtocolSFTP))
+
+		hookCmd, err := exec.LookPath("true")
+		assert.NoError(t, err)
+		Config.PostConnectHook = hookCmd
+		assert.NoError(t, Config.ExecutePostConnectHook(remoteAddr.String(), ProtocolSFTP))
+	}
+
+	Config.PostConnectHook = ""
+}

common/connection.go

@@ -0,0 +1,957 @@
+package common
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"path"
+	"strings"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"github.com/pkg/sftp"
+
+	"github.com/drakkan/sftpgo/dataprovider"
+	"github.com/drakkan/sftpgo/logger"
+	"github.com/drakkan/sftpgo/utils"
+	"github.com/drakkan/sftpgo/vfs"
+)
+
+// BaseConnection defines common fields for a connection using any supported protocol
+type BaseConnection struct {
+	// Unique identifier for the connection
+	ID string
+	// user associated with this connection if any
+	User dataprovider.User
+	// start time for this connection
+	startTime time.Time
+	protocol  string
+	Fs        vfs.Fs
+	sync.RWMutex
+	// last activity for this connection
+	lastActivity    int64
+	transferID      uint64
+	activeTransfers []ActiveTransfer
+}
+
+// NewBaseConnection returns a new BaseConnection
+func NewBaseConnection(ID, protocol string, user dataprovider.User, fs vfs.Fs) *BaseConnection {
+	connID := ID
+	if utils.IsStringInSlice(protocol, supportedProtocols) {
+		connID = fmt.Sprintf("%v_%v", protocol, ID)
+	}
+	return &BaseConnection{
+		ID:           connID,
+		User:         user,
+		startTime:    time.Now(),
+		protocol:     protocol,
+		Fs:           fs,
+		lastActivity: time.Now().UnixNano(),
+		transferID:   0,
+	}
+}
+
+// Log outputs a log entry to the configured logger
+func (c *BaseConnection) Log(level logger.LogLevel, format string, v ...interface{}) {
+	logger.Log(level, c.protocol, c.ID, format, v...)
+}
+
+// GetTransferID returns an unique transfer ID for this connection
+func (c *BaseConnection) GetTransferID() uint64 {
+	return atomic.AddUint64(&c.transferID, 1)
+}
+
+// GetID returns the connection ID
+func (c *BaseConnection) GetID() string {
+	return c.ID
+}
+
+// GetUsername returns the authenticated username associated with this connection if any
+func (c *BaseConnection) GetUsername() string {
+	return c.User.Username
+}
+
+// GetProtocol returns the protocol for the connection
+func (c *BaseConnection) GetProtocol() string {
+	return c.protocol
+}
+
+// SetProtocol sets the protocol for this connection
+func (c *BaseConnection) SetProtocol(protocol string) {
+	c.protocol = protocol
+	if utils.IsStringInSlice(c.protocol, supportedProtocols) {
+		c.ID = fmt.Sprintf("%v_%v", c.protocol, c.ID)
+	}
+}
+
+// GetConnectionTime returns the initial connection time
+func (c *BaseConnection) GetConnectionTime() time.Time {
+	return c.startTime
+}
+
+// UpdateLastActivity updates last activity for this connection
+func (c *BaseConnection) UpdateLastActivity() {
+	atomic.StoreInt64(&c.lastActivity, time.Now().UnixNano())
+}
+
+// GetLastActivity returns the last connection activity
+func (c *BaseConnection) GetLastActivity() time.Time {
+	return time.Unix(0, atomic.LoadInt64(&c.lastActivity))
+}
+
+// AddTransfer associates a new transfer to this connection
+func (c *BaseConnection) AddTransfer(t ActiveTransfer) {
+	c.Lock()
+	defer c.Unlock()
+
+	c.activeTransfers = append(c.activeTransfers, t)
+	c.Log(logger.LevelDebug, "transfer added, id: %v, active transfers: %v", t.GetID(), len(c.activeTransfers))
+}
+
+// RemoveTransfer removes the specified transfer from the active ones
+func (c *BaseConnection) RemoveTransfer(t ActiveTransfer) {
+	c.Lock()
+	defer c.Unlock()
+
+	indexToRemove := -1
+	for i, v := range c.activeTransfers {
+		if v.GetID() == t.GetID() {
+			indexToRemove = i
+			break
+		}
+	}
+	if indexToRemove >= 0 {
+		c.activeTransfers[indexToRemove] = c.activeTransfers[len(c.activeTransfers)-1]
+		c.activeTransfers[len(c.activeTransfers)-1] = nil
+		c.activeTransfers = c.activeTransfers[:len(c.activeTransfers)-1]
+		c.Log(logger.LevelDebug, "transfer removed, id: %v active transfers: %v", t.GetID(), len(c.activeTransfers))
+	} else {
+		c.Log(logger.LevelWarn, "transfer to remove not found!")
+	}
+}
+
+// GetTransfers returns the active transfers
+func (c *BaseConnection) GetTransfers() []ConnectionTransfer {
+	c.RLock()
+	defer c.RUnlock()
+
+	transfers := make([]ConnectionTransfer, 0, len(c.activeTransfers))
+	for _, t := range c.activeTransfers {
+		var operationType string
+		switch t.GetType() {
+		case TransferDownload:
+			operationType = operationDownload
+		case TransferUpload:
+			operationType = operationUpload
+		}
+		transfers = append(transfers, ConnectionTransfer{
+			ID:            t.GetID(),
+			OperationType: operationType,
+			StartTime:     utils.GetTimeAsMsSinceEpoch(t.GetStartTime()),
+			Size:          t.GetSize(),
+			VirtualPath:   t.GetVirtualPath(),
+		})
+	}
+
+	return transfers
+}
+
+// SignalTransfersAbort signals to the active transfers to exit as soon as possible
+func (c *BaseConnection) SignalTransfersAbort() error {
+	c.RLock()
+	defer c.RUnlock()
+
+	if len(c.activeTransfers) == 0 {
+		return errors.New("no active transfer found")
+	}
+
+	for _, t := range c.activeTransfers {
+		t.SignalClose()
+	}
+	return nil
+}
+
+func (c *BaseConnection) getRealFsPath(fsPath string) string {
+	c.RLock()
+	defer c.RUnlock()
+
+	for _, t := range c.activeTransfers {
+		if p := t.GetRealFsPath(fsPath); len(p) > 0 {
+			return p
+		}
+	}
+	return fsPath
+}
+
+func (c *BaseConnection) truncateOpenHandle(fsPath string, size int64) (int64, error) {
+	c.RLock()
+	defer c.RUnlock()
+
+	for _, t := range c.activeTransfers {
+		initialSize, err := t.Truncate(fsPath, size)
+		if err != errTransferMismatch {
+			return initialSize, err
+		}
+	}
+
+	return 0, errNoTransfer
+}
+
+// ListDir reads the directory named by fsPath and returns a list of directory entries
+func (c *BaseConnection) ListDir(fsPath, virtualPath string) ([]os.FileInfo, error) {
+	if !c.User.HasPerm(dataprovider.PermListItems, virtualPath) {
+		return nil, c.GetPermissionDeniedError()
+	}
+	files, err := c.Fs.ReadDir(fsPath)
+	if err != nil {
+		c.Log(logger.LevelWarn, "error listing directory: %+v", err)
+		return nil, c.GetFsError(err)
+	}
+	return c.User.AddVirtualDirs(files, virtualPath), nil
+}
+
+// CreateDir creates a new directory at the specified fsPath
+func (c *BaseConnection) CreateDir(fsPath, virtualPath string) error {
+	if !c.User.HasPerm(dataprovider.PermCreateDirs, path.Dir(virtualPath)) {
+		return c.GetPermissionDeniedError()
+	}
+	if c.User.IsVirtualFolder(virtualPath) {
+		c.Log(logger.LevelWarn, "mkdir not allowed %#v is a virtual folder", virtualPath)
+		return c.GetPermissionDeniedError()
+	}
+	if err := c.Fs.Mkdir(fsPath); err != nil {
+		c.Log(logger.LevelWarn, "error creating dir: %#v error: %+v", fsPath, err)
+		return c.GetFsError(err)
+	}
+	vfs.SetPathPermissions(c.Fs, fsPath, c.User.GetUID(), c.User.GetGID())
+
+	logger.CommandLog(mkdirLogSender, fsPath, "", c.User.Username, "", c.ID, c.protocol, -1, -1, "", "", "", -1)
+	return nil
+}
+
+// IsRemoveFileAllowed returns an error if removing this file is not allowed
+func (c *BaseConnection) IsRemoveFileAllowed(fsPath, virtualPath string) error {
+	if !c.User.HasPerm(dataprovider.PermDelete, path.Dir(virtualPath)) {
+		return c.GetPermissionDeniedError()
+	}
+	if !c.User.IsFileAllowed(virtualPath) {
+		c.Log(logger.LevelDebug, "removing file %#v is not allowed", fsPath)
+		return c.GetPermissionDeniedError()
+	}
+	return nil
+}
+
+// RemoveFile removes a file at the specified fsPath
+func (c *BaseConnection) RemoveFile(fsPath, virtualPath string, info os.FileInfo) error {
+	if err := c.IsRemoveFileAllowed(fsPath, virtualPath); err != nil {
+		return err
+	}
+	size := info.Size()
+	action := newActionNotification(&c.User, operationPreDelete, fsPath, "", "", c.protocol, size, nil)
+	actionErr := action.execute()
+	if actionErr == nil {
+		c.Log(logger.LevelDebug, "remove for path %#v handled by pre-delete action", fsPath)
+	} else {
+		if err := c.Fs.Remove(fsPath, false); err != nil {
+			c.Log(logger.LevelWarn, "failed to remove a file/symlink %#v: %+v", fsPath, err)
+			return c.GetFsError(err)
+		}
+	}
+
+	logger.CommandLog(removeLogSender, fsPath, "", c.User.Username, "", c.ID, c.protocol, -1, -1, "", "", "", -1)
+	if info.Mode()&os.ModeSymlink != os.ModeSymlink {
+		vfolder, err := c.User.GetVirtualFolderForPath(path.Dir(virtualPath))
+		if err == nil {
+			dataprovider.UpdateVirtualFolderQuota(vfolder.BaseVirtualFolder, -1, -size, false) //nolint:errcheck
+			if vfolder.IsIncludedInUserQuota() {
+				dataprovider.UpdateUserQuota(c.User, -1, -size, false) //nolint:errcheck
+			}
+		} else {
+			dataprovider.UpdateUserQuota(c.User, -1, -size, false) //nolint:errcheck
+		}
+	}
+	if actionErr != nil {
+		action := newActionNotification(&c.User, operationDelete, fsPath, "", "", c.protocol, size, nil)
+		go action.execute() //nolint:errcheck
+	}
+	return nil
+}
+
+// IsRemoveDirAllowed returns an error if removing this directory is not allowed
+func (c *BaseConnection) IsRemoveDirAllowed(fsPath, virtualPath string) error {
+	if c.Fs.GetRelativePath(fsPath) == "/" {
+		c.Log(logger.LevelWarn, "removing root dir is not allowed")
+		return c.GetPermissionDeniedError()
+	}
+	if c.User.IsVirtualFolder(virtualPath) {
+		c.Log(logger.LevelWarn, "removing a virtual folder is not allowed: %#v", virtualPath)
+		return c.GetPermissionDeniedError()
+	}
+	if c.User.HasVirtualFoldersInside(virtualPath) {
+		c.Log(logger.LevelWarn, "removing a directory with a virtual folder inside is not allowed: %#v", virtualPath)
+		return c.GetOpUnsupportedError()
+	}
+	if c.User.IsMappedPath(fsPath) {
+		c.Log(logger.LevelWarn, "removing a directory mapped as virtual folder is not allowed: %#v", fsPath)
+		return c.GetPermissionDeniedError()
+	}
+	if !c.User.HasPerm(dataprovider.PermDelete, path.Dir(virtualPath)) {
+		return c.GetPermissionDeniedError()
+	}
+	return nil
+}
+
+// RemoveDir removes a directory at the specified fsPath
+func (c *BaseConnection) RemoveDir(fsPath, virtualPath string) error {
+	if err := c.IsRemoveDirAllowed(fsPath, virtualPath); err != nil {
+		return err
+	}
+
+	var fi os.FileInfo
+	var err error
+	if fi, err = c.Fs.Lstat(fsPath); err != nil {
+		// see #149
+		if c.Fs.IsNotExist(err) && c.Fs.HasVirtualFolders() {
+			return nil
+		}
+		c.Log(logger.LevelWarn, "failed to remove a dir %#v: stat error: %+v", fsPath, err)
+		return c.GetFsError(err)
+	}
+	if !fi.IsDir() || fi.Mode()&os.ModeSymlink == os.ModeSymlink {
+		c.Log(logger.LevelDebug, "cannot remove %#v is not a directory", fsPath)
+		return c.GetGenericError(nil)
+	}
+
+	if err := c.Fs.Remove(fsPath, true); err != nil {
+		c.Log(logger.LevelWarn, "failed to remove directory %#v: %+v", fsPath, err)
+		return c.GetFsError(err)
+	}
+
+	logger.CommandLog(rmdirLogSender, fsPath, "", c.User.Username, "", c.ID, c.protocol, -1, -1, "", "", "", -1)
+	return nil
+}
+
+// Rename renames (moves) fsSourcePath to fsTargetPath
+func (c *BaseConnection) Rename(fsSourcePath, fsTargetPath, virtualSourcePath, virtualTargetPath string) error {
+	if c.User.IsMappedPath(fsSourcePath) {
+		c.Log(logger.LevelWarn, "renaming a directory mapped as virtual folder is not allowed: %#v", fsSourcePath)
+		return c.GetPermissionDeniedError()
+	}
+	if c.User.IsMappedPath(fsTargetPath) {
+		c.Log(logger.LevelWarn, "renaming to a directory mapped as virtual folder is not allowed: %#v", fsTargetPath)
+		return c.GetPermissionDeniedError()
+	}
+	srcInfo, err := c.Fs.Lstat(fsSourcePath)
+	if err != nil {
+		return c.GetFsError(err)
+	}
+	if !c.isRenamePermitted(fsSourcePath, virtualSourcePath, virtualTargetPath, srcInfo) {
+		return c.GetPermissionDeniedError()
+	}
+	initialSize := int64(-1)
+	if dstInfo, err := c.Fs.Lstat(fsTargetPath); err == nil {
+		if dstInfo.IsDir() {
+			c.Log(logger.LevelWarn, "attempted to rename %#v overwriting an existing directory %#v",
+				fsSourcePath, fsTargetPath)
+			return c.GetOpUnsupportedError()
+		}
+		// we are overwriting an existing file/symlink
+		if dstInfo.Mode().IsRegular() {
+			initialSize = dstInfo.Size()
+		}
+		if !c.User.HasPerm(dataprovider.PermOverwrite, path.Dir(virtualTargetPath)) {
+			c.Log(logger.LevelDebug, "renaming is not allowed, %#v -> %#v. Target exists but the user "+
+				"has no overwrite permission", virtualSourcePath, virtualTargetPath)
+			return c.GetPermissionDeniedError()
+		}
+	}
+	if srcInfo.IsDir() {
+		if c.User.HasVirtualFoldersInside(virtualSourcePath) {
+			c.Log(logger.LevelDebug, "renaming the folder %#v is not supported: it has virtual folders inside it",
+				virtualSourcePath)
+			return c.GetOpUnsupportedError()
+		}
+		if err = c.checkRecursiveRenameDirPermissions(fsSourcePath, fsTargetPath); err != nil {
+			c.Log(logger.LevelDebug, "error checking recursive permissions before renaming %#v: %+v", fsSourcePath, err)
+			return c.GetFsError(err)
+		}
+	}
+	if !c.hasSpaceForRename(virtualSourcePath, virtualTargetPath, initialSize, fsSourcePath) {
+		c.Log(logger.LevelInfo, "denying cross rename due to space limit")
+		return c.GetGenericError(ErrQuotaExceeded)
+	}
+	if err := c.Fs.Rename(fsSourcePath, fsTargetPath); err != nil {
+		c.Log(logger.LevelWarn, "failed to rename %#v -> %#v: %+v", fsSourcePath, fsTargetPath, err)
+		return c.GetFsError(err)
+	}
+	if dataprovider.GetQuotaTracking() > 0 {
+		c.updateQuotaAfterRename(virtualSourcePath, virtualTargetPath, fsTargetPath, initialSize) //nolint:errcheck
+	}
+	logger.CommandLog(renameLogSender, fsSourcePath, fsTargetPath, c.User.Username, "", c.ID, c.protocol, -1, -1,
+		"", "", "", -1)
+	action := newActionNotification(&c.User, operationRename, fsSourcePath, fsTargetPath, "", c.protocol, 0, nil)
+	// the returned error is used in test cases only, we already log the error inside action.execute
+	go action.execute() //nolint:errcheck
+
+	return nil
+}
+
+// CreateSymlink creates fsTargetPath as a symbolic link to fsSourcePath
+func (c *BaseConnection) CreateSymlink(fsSourcePath, fsTargetPath, virtualSourcePath, virtualTargetPath string) error {
+	if c.Fs.GetRelativePath(fsSourcePath) == "/" {
+		c.Log(logger.LevelWarn, "symlinking root dir is not allowed")
+		return c.GetPermissionDeniedError()
+	}
+	if c.User.IsVirtualFolder(virtualTargetPath) {
+		c.Log(logger.LevelWarn, "symlinking a virtual folder is not allowed")
+		return c.GetPermissionDeniedError()
+	}
+	if !c.User.HasPerm(dataprovider.PermCreateSymlinks, path.Dir(virtualTargetPath)) {
+		return c.GetPermissionDeniedError()
+	}
+	if c.isCrossFoldersRequest(virtualSourcePath, virtualTargetPath) {
+		c.Log(logger.LevelWarn, "cross folder symlink is not supported, src: %v dst: %v", virtualSourcePath, virtualTargetPath)
+		return c.GetOpUnsupportedError()
+	}
+	if c.User.IsMappedPath(fsSourcePath) {
+		c.Log(logger.LevelWarn, "symlinking a directory mapped as virtual folder is not allowed: %#v", fsSourcePath)
+		return c.GetPermissionDeniedError()
+	}
+	if c.User.IsMappedPath(fsTargetPath) {
+		c.Log(logger.LevelWarn, "symlinking to a directory mapped as virtual folder is not allowed: %#v", fsTargetPath)
+		return c.GetPermissionDeniedError()
+	}
+	if err := c.Fs.Symlink(fsSourcePath, fsTargetPath); err != nil {
+		c.Log(logger.LevelWarn, "failed to create symlink %#v -> %#v: %+v", fsSourcePath, fsTargetPath, err)
+		return c.GetFsError(err)
+	}
+	logger.CommandLog(symlinkLogSender, fsSourcePath, fsTargetPath, c.User.Username, "", c.ID, c.protocol, -1, -1, "", "", "", -1)
+	return nil
+}
+
+func (c *BaseConnection) getPathForSetStatPerms(fsPath, virtualPath string) string {
+	pathForPerms := virtualPath
+	if fi, err := c.Fs.Lstat(fsPath); err == nil {
+		if fi.IsDir() {
+			pathForPerms = path.Dir(virtualPath)
+		}
+	}
+	return pathForPerms
+}
+
+// DoStat execute a Stat if mode = 0, Lstat if mode = 1
+func (c *BaseConnection) DoStat(fsPath string, mode int) (os.FileInfo, error) {
+	if mode == 1 {
+		return c.Fs.Lstat(c.getRealFsPath(fsPath))
+	}
+	return c.Fs.Stat(c.getRealFsPath(fsPath))
+}
+
+// SetStat set StatAttributes for the specified fsPath
+func (c *BaseConnection) SetStat(fsPath, virtualPath string, attributes *StatAttributes) error {
+	if Config.SetstatMode == 1 {
+		return nil
+	}
+	pathForPerms := c.getPathForSetStatPerms(fsPath, virtualPath)
+
+	if attributes.Flags&StatAttrPerms != 0 {
+		if !c.User.HasPerm(dataprovider.PermChmod, pathForPerms) {
+			return c.GetPermissionDeniedError()
+		}
+		if err := c.Fs.Chmod(c.getRealFsPath(fsPath), attributes.Mode); err != nil {
+			c.Log(logger.LevelWarn, "failed to chmod path %#v, mode: %v, err: %+v", fsPath, attributes.Mode.String(), err)
+			return c.GetFsError(err)
+		}
+		logger.CommandLog(chmodLogSender, fsPath, "", c.User.Username, attributes.Mode.String(), c.ID, c.protocol,
+			-1, -1, "", "", "", -1)
+	}
+
+	if attributes.Flags&StatAttrUIDGID != 0 {
+		if !c.User.HasPerm(dataprovider.PermChown, pathForPerms) {
+			return c.GetPermissionDeniedError()
+		}
+		if err := c.Fs.Chown(c.getRealFsPath(fsPath), attributes.UID, attributes.GID); err != nil {
+			c.Log(logger.LevelWarn, "failed to chown path %#v, uid: %v, gid: %v, err: %+v", fsPath, attributes.UID,
+				attributes.GID, err)
+			return c.GetFsError(err)
+		}
+		logger.CommandLog(chownLogSender, fsPath, "", c.User.Username, "", c.ID, c.protocol, attributes.UID, attributes.GID,
+			"", "", "", -1)
+	}
+
+	if attributes.Flags&StatAttrTimes != 0 {
+		if !c.User.HasPerm(dataprovider.PermChtimes, pathForPerms) {
+			return c.GetPermissionDeniedError()
+		}
+
+		if err := c.Fs.Chtimes(c.getRealFsPath(fsPath), attributes.Atime, attributes.Mtime); err != nil {
+			c.Log(logger.LevelWarn, "failed to chtimes for path %#v, access time: %v, modification time: %v, err: %+v",
+				fsPath, attributes.Atime, attributes.Mtime, err)
+			return c.GetFsError(err)
+		}
+		accessTimeString := attributes.Atime.Format(chtimesFormat)
+		modificationTimeString := attributes.Mtime.Format(chtimesFormat)
+		logger.CommandLog(chtimesLogSender, fsPath, "", c.User.Username, "", c.ID, c.protocol, -1, -1,
+			accessTimeString, modificationTimeString, "", -1)
+	}
+
+	if attributes.Flags&StatAttrSize != 0 {
+		if !c.User.HasPerm(dataprovider.PermOverwrite, pathForPerms) {
+			return c.GetPermissionDeniedError()
+		}
+
+		if err := c.truncateFile(fsPath, virtualPath, attributes.Size); err != nil {
+			c.Log(logger.LevelWarn, "failed to truncate path %#v, size: %v, err: %+v", fsPath, attributes.Size, err)
+			return c.GetFsError(err)
+		}
+		logger.CommandLog(truncateLogSender, fsPath, "", c.User.Username, "", c.ID, c.protocol, -1, -1, "", "", "", attributes.Size)
+	}
+
+	return nil
+}
+
+func (c *BaseConnection) truncateFile(fsPath, virtualPath string, size int64) error {
+	// check first if we have an open transfer for the given path and try to truncate the file already opened
+	// if we found no transfer we truncate by path.
+	var initialSize int64
+	var err error
+	initialSize, err = c.truncateOpenHandle(fsPath, size)
+	if err == errNoTransfer {
+		c.Log(logger.LevelDebug, "file path %#v not found in active transfers, execute trucate by path", fsPath)
+		var info os.FileInfo
+		info, err = c.Fs.Stat(fsPath)
+		if err != nil {
+			return err
+		}
+		initialSize = info.Size()
+		err = c.Fs.Truncate(fsPath, size)
+	}
+	if err == nil && vfs.IsLocalOsFs(c.Fs) {
+		sizeDiff := initialSize - size
+		vfolder, err := c.User.GetVirtualFolderForPath(path.Dir(virtualPath))
+		if err == nil {
+			dataprovider.UpdateVirtualFolderQuota(vfolder.BaseVirtualFolder, 0, -sizeDiff, false) //nolint:errcheck
+			if vfolder.IsIncludedInUserQuota() {
+				dataprovider.UpdateUserQuota(c.User, 0, -sizeDiff, false) //nolint:errcheck
+			}
+		} else {
+			dataprovider.UpdateUserQuota(c.User, 0, -sizeDiff, false) //nolint:errcheck
+		}
+	}
+	return err
+}
+
+func (c *BaseConnection) checkRecursiveRenameDirPermissions(sourcePath, targetPath string) error {
+	dstPerms := []string{
+		dataprovider.PermCreateDirs,
+		dataprovider.PermUpload,
+		dataprovider.PermCreateSymlinks,
+	}
+
+	err := c.Fs.Walk(sourcePath, func(walkedPath string, info os.FileInfo, err error) error {
+		if err != nil {
+			return err
+		}
+		dstPath := strings.Replace(walkedPath, sourcePath, targetPath, 1)
+		virtualSrcPath := c.Fs.GetRelativePath(walkedPath)
+		virtualDstPath := c.Fs.GetRelativePath(dstPath)
+		// walk scans the directory tree in order, checking the parent directory permissions we are sure that all contents
+		// inside the parent path was checked. If the current dir has no subdirs with defined permissions inside it
+		// and it has all the possible permissions we can stop scanning
+		if !c.User.HasPermissionsInside(path.Dir(virtualSrcPath)) && !c.User.HasPermissionsInside(path.Dir(virtualDstPath)) {
+			if c.User.HasPerm(dataprovider.PermRename, path.Dir(virtualSrcPath)) &&
+				c.User.HasPerm(dataprovider.PermRename, path.Dir(virtualDstPath)) {
+				return ErrSkipPermissionsCheck
+			}
+			if c.User.HasPerm(dataprovider.PermDelete, path.Dir(virtualSrcPath)) &&
+				c.User.HasPerms(dstPerms, path.Dir(virtualDstPath)) {
+				return ErrSkipPermissionsCheck
+			}
+		}
+		if !c.isRenamePermitted(walkedPath, virtualSrcPath, virtualDstPath, info) {
+			c.Log(logger.LevelInfo, "rename %#v -> %#v is not allowed, virtual destination path: %#v",
+				walkedPath, dstPath, virtualDstPath)
+			return os.ErrPermission
+		}
+		return nil
+	})
+	if err == ErrSkipPermissionsCheck {
+		err = nil
+	}
+	return err
+}
+
+func (c *BaseConnection) isRenamePermitted(fsSourcePath, virtualSourcePath, virtualTargetPath string, fi os.FileInfo) bool {
+	if c.Fs.GetRelativePath(fsSourcePath) == "/" {
+		c.Log(logger.LevelWarn, "renaming root dir is not allowed")
+		return false
+	}
+	if c.User.IsVirtualFolder(virtualSourcePath) || c.User.IsVirtualFolder(virtualTargetPath) {
+		c.Log(logger.LevelWarn, "renaming a virtual folder is not allowed")
+		return false
+	}
+	if !c.User.IsFileAllowed(virtualSourcePath) || !c.User.IsFileAllowed(virtualTargetPath) {
+		if fi != nil && fi.Mode().IsRegular() {
+			c.Log(logger.LevelDebug, "renaming file is not allowed, source: %#v target: %#v",
+				virtualSourcePath, virtualTargetPath)
+			return false
+		}
+	}
+	if c.User.HasPerm(dataprovider.PermRename, path.Dir(virtualSourcePath)) &&
+		c.User.HasPerm(dataprovider.PermRename, path.Dir(virtualTargetPath)) {
+		return true
+	}
+	if !c.User.HasPerm(dataprovider.PermDelete, path.Dir(virtualSourcePath)) {
+		return false
+	}
+	if fi != nil {
+		if fi.IsDir() {
+			return c.User.HasPerm(dataprovider.PermCreateDirs, path.Dir(virtualTargetPath))
+		} else if fi.Mode()&os.ModeSymlink == os.ModeSymlink {
+			return c.User.HasPerm(dataprovider.PermCreateSymlinks, path.Dir(virtualTargetPath))
+		}
+	}
+	return c.User.HasPerm(dataprovider.PermUpload, path.Dir(virtualTargetPath))
+}
+
+func (c *BaseConnection) hasSpaceForRename(virtualSourcePath, virtualTargetPath string, initialSize int64,
+	fsSourcePath string) bool {
+	if dataprovider.GetQuotaTracking() == 0 {
+		return true
+	}
+	sourceFolder, errSrc := c.User.GetVirtualFolderForPath(path.Dir(virtualSourcePath))
+	dstFolder, errDst := c.User.GetVirtualFolderForPath(path.Dir(virtualTargetPath))
+	if errSrc != nil && errDst != nil {
+		// rename inside the user home dir
+		return true
+	}
+	if errSrc == nil && errDst == nil {
+		// rename between virtual folders
+		if sourceFolder.MappedPath == dstFolder.MappedPath {
+			// rename inside the same virtual folder
+			return true
+		}
+	}
+	if errSrc != nil && dstFolder.IsIncludedInUserQuota() {
+		// rename between user root dir and a virtual folder included in user quota
+		return true
+	}
+	quotaResult := c.HasSpace(true, virtualTargetPath)
+	return c.hasSpaceForCrossRename(quotaResult, initialSize, fsSourcePath)
+}
+
+// hasSpaceForCrossRename checks the quota after a rename between different folders
+func (c *BaseConnection) hasSpaceForCrossRename(quotaResult vfs.QuotaCheckResult, initialSize int64, sourcePath string) bool {
+	if !quotaResult.HasSpace && initialSize == -1 {
+		// we are over quota and this is not a file replace
+		return false
+	}
+	fi, err := c.Fs.Lstat(sourcePath)
+	if err != nil {
+		c.Log(logger.LevelWarn, "cross rename denied, stat error for path %#v: %v", sourcePath, err)
+		return false
+	}
+	var sizeDiff int64
+	var filesDiff int
+	if fi.Mode().IsRegular() {
+		sizeDiff = fi.Size()
+		filesDiff = 1
+		if initialSize != -1 {
+			sizeDiff -= initialSize
+			filesDiff = 0
+		}
+	} else if fi.IsDir() {
+		filesDiff, sizeDiff, err = c.Fs.GetDirSize(sourcePath)
+		if err != nil {
+			c.Log(logger.LevelWarn, "cross rename denied, error getting size for directory %#v: %v", sourcePath, err)
+			return false
+		}
+	}
+	if !quotaResult.HasSpace && initialSize != -1 {
+		// we are over quota but we are overwriting an existing file so we check if the quota size after the rename is ok
+		if quotaResult.QuotaSize == 0 {
+			return true
+		}
+		c.Log(logger.LevelDebug, "cross rename overwrite, source %#v, used size %v, size to add %v",
+			sourcePath, quotaResult.UsedSize, sizeDiff)
+		quotaResult.UsedSize += sizeDiff
+		return quotaResult.GetRemainingSize() >= 0
+	}
+	if quotaResult.QuotaFiles > 0 {
+		remainingFiles := quotaResult.GetRemainingFiles()
+		c.Log(logger.LevelDebug, "cross rename, source %#v remaining file %v to add %v", sourcePath,
+			remainingFiles, filesDiff)
+		if remainingFiles < filesDiff {
+			return false
+		}
+	}
+	if quotaResult.QuotaSize > 0 {
+		remainingSize := quotaResult.GetRemainingSize()
+		c.Log(logger.LevelDebug, "cross rename, source %#v remaining size %v to add %v", sourcePath,
+			remainingSize, sizeDiff)
+		if remainingSize < sizeDiff {
+			return false
+		}
+	}
+	return true
+}
+
+// GetMaxWriteSize returns the allowed size for an upload or an error
+// if no enough size is available for a resume/append
+func (c *BaseConnection) GetMaxWriteSize(quotaResult vfs.QuotaCheckResult, isResume bool, fileSize int64) (int64, error) {
+	maxWriteSize := quotaResult.GetRemainingSize()
+
+	if isResume {
+		if !c.Fs.IsUploadResumeSupported() {
+			return 0, c.GetOpUnsupportedError()
+		}
+		if c.User.Filters.MaxUploadFileSize > 0 && c.User.Filters.MaxUploadFileSize <= fileSize {
+			return 0, ErrQuotaExceeded
+		}
+		if c.User.Filters.MaxUploadFileSize > 0 {
+			maxUploadSize := c.User.Filters.MaxUploadFileSize - fileSize
+			if maxUploadSize < maxWriteSize || maxWriteSize == 0 {
+				maxWriteSize = maxUploadSize
+			}
+		}
+	} else {
+		if maxWriteSize > 0 {
+			maxWriteSize += fileSize
+		}
+		if c.User.Filters.MaxUploadFileSize > 0 && (c.User.Filters.MaxUploadFileSize < maxWriteSize || maxWriteSize == 0) {
+			maxWriteSize = c.User.Filters.MaxUploadFileSize
+		}
+	}
+
+	return maxWriteSize, nil
+}
+
+// HasSpace checks user's quota usage
+func (c *BaseConnection) HasSpace(checkFiles bool, requestPath string) vfs.QuotaCheckResult {
+	result := vfs.QuotaCheckResult{
+		HasSpace:     true,
+		AllowedSize:  0,
+		AllowedFiles: 0,
+		UsedSize:     0,
+		UsedFiles:    0,
+		QuotaSize:    0,
+		QuotaFiles:   0,
+	}
+
+	if dataprovider.GetQuotaTracking() == 0 {
+		return result
+	}
+	var err error
+	var vfolder vfs.VirtualFolder
+	vfolder, err = c.User.GetVirtualFolderForPath(path.Dir(requestPath))
+	if err == nil && !vfolder.IsIncludedInUserQuota() {
+		if vfolder.HasNoQuotaRestrictions(checkFiles) {
+			return result
+		}
+		result.QuotaSize = vfolder.QuotaSize
+		result.QuotaFiles = vfolder.QuotaFiles
+		result.UsedFiles, result.UsedSize, err = dataprovider.GetUsedVirtualFolderQuota(vfolder.MappedPath)
+	} else {
+		if c.User.HasNoQuotaRestrictions(checkFiles) {
+			return result
+		}
+		result.QuotaSize = c.User.QuotaSize
+		result.QuotaFiles = c.User.QuotaFiles
+		result.UsedFiles, result.UsedSize, err = dataprovider.GetUsedQuota(c.User.Username)
+	}
+	if err != nil {
+		c.Log(logger.LevelWarn, "error getting used quota for %#v request path %#v: %v", c.User.Username, requestPath, err)
+		result.HasSpace = false
+		return result
+	}
+	result.AllowedFiles = result.QuotaFiles - result.UsedFiles
+	result.AllowedSize = result.QuotaSize - result.UsedSize
+	if (checkFiles && result.QuotaFiles > 0 && result.UsedFiles >= result.QuotaFiles) ||
+		(result.QuotaSize > 0 && result.UsedSize >= result.QuotaSize) {
+		c.Log(logger.LevelDebug, "quota exceed for user %#v, request path %#v, num files: %v/%v, size: %v/%v check files: %v",
+			c.User.Username, requestPath, result.UsedFiles, result.QuotaFiles, result.UsedSize, result.QuotaSize, checkFiles)
+		result.HasSpace = false
+		return result
+	}
+	return result
+}
+
+func (c *BaseConnection) isCrossFoldersRequest(virtualSourcePath, virtualTargetPath string) bool {
+	sourceFolder, errSrc := c.User.GetVirtualFolderForPath(virtualSourcePath)
+	dstFolder, errDst := c.User.GetVirtualFolderForPath(virtualTargetPath)
+	if errSrc != nil && errDst != nil {
+		return false
+	}
+	if errSrc == nil && errDst == nil {
+		return sourceFolder.MappedPath != dstFolder.MappedPath
+	}
+	return true
+}
+
+func (c *BaseConnection) updateQuotaMoveBetweenVFolders(sourceFolder, dstFolder vfs.VirtualFolder, initialSize,
+	filesSize int64, numFiles int) {
+	if sourceFolder.MappedPath == dstFolder.MappedPath {
+		// both files are inside the same virtual folder
+		if initialSize != -1 {
+			dataprovider.UpdateVirtualFolderQuota(dstFolder.BaseVirtualFolder, -numFiles, -initialSize, false) //nolint:errcheck
+			if dstFolder.IsIncludedInUserQuota() {
+				dataprovider.UpdateUserQuota(c.User, -numFiles, -initialSize, false) //nolint:errcheck
+			}
+		}
+		return
+	}
+	// files are inside different virtual folders
+	dataprovider.UpdateVirtualFolderQuota(sourceFolder.BaseVirtualFolder, -numFiles, -filesSize, false) //nolint:errcheck
+	if sourceFolder.IsIncludedInUserQuota() {
+		dataprovider.UpdateUserQuota(c.User, -numFiles, -filesSize, false) //nolint:errcheck
+	}
+	if initialSize == -1 {
+		dataprovider.UpdateVirtualFolderQuota(dstFolder.BaseVirtualFolder, numFiles, filesSize, false) //nolint:errcheck
+		if dstFolder.IsIncludedInUserQuota() {
+			dataprovider.UpdateUserQuota(c.User, numFiles, filesSize, false) //nolint:errcheck
+		}
+	} else {
+		// we cannot have a directory here, initialSize != -1 only for files
+		dataprovider.UpdateVirtualFolderQuota(dstFolder.BaseVirtualFolder, 0, filesSize-initialSize, false) //nolint:errcheck
+		if dstFolder.IsIncludedInUserQuota() {
+			dataprovider.UpdateUserQuota(c.User, 0, filesSize-initialSize, false) //nolint:errcheck
+		}
+	}
+}
+
+func (c *BaseConnection) updateQuotaMoveFromVFolder(sourceFolder vfs.VirtualFolder, initialSize, filesSize int64, numFiles int) {
+	// move between a virtual folder and the user home dir
+	dataprovider.UpdateVirtualFolderQuota(sourceFolder.BaseVirtualFolder, -numFiles, -filesSize, false) //nolint:errcheck
+	if sourceFolder.IsIncludedInUserQuota() {
+		dataprovider.UpdateUserQuota(c.User, -numFiles, -filesSize, false) //nolint:errcheck
+	}
+	if initialSize == -1 {
+		dataprovider.UpdateUserQuota(c.User, numFiles, filesSize, false) //nolint:errcheck
+	} else {
+		// we cannot have a directory here, initialSize != -1 only for files
+		dataprovider.UpdateUserQuota(c.User, 0, filesSize-initialSize, false) //nolint:errcheck
+	}
+}
+
+func (c *BaseConnection) updateQuotaMoveToVFolder(dstFolder vfs.VirtualFolder, initialSize, filesSize int64, numFiles int) {
+	// move between the user home dir and a virtual folder
+	dataprovider.UpdateUserQuota(c.User, -numFiles, -filesSize, false) //nolint:errcheck
+	if initialSize == -1 {
+		dataprovider.UpdateVirtualFolderQuota(dstFolder.BaseVirtualFolder, numFiles, filesSize, false) //nolint:errcheck
+		if dstFolder.IsIncludedInUserQuota() {
+			dataprovider.UpdateUserQuota(c.User, numFiles, filesSize, false) //nolint:errcheck
+		}
+	} else {
+		// we cannot have a directory here, initialSize != -1 only for files
+		dataprovider.UpdateVirtualFolderQuota(dstFolder.BaseVirtualFolder, 0, filesSize-initialSize, false) //nolint:errcheck
+		if dstFolder.IsIncludedInUserQuota() {
+			dataprovider.UpdateUserQuota(c.User, 0, filesSize-initialSize, false) //nolint:errcheck
+		}
+	}
+}
+
+func (c *BaseConnection) updateQuotaAfterRename(virtualSourcePath, virtualTargetPath, targetPath string, initialSize int64) error {
+	// we don't allow to overwrite an existing directory so targetPath can be:
+	// - a new file, a symlink is as a new file here
+	// - a file overwriting an existing one
+	// - a new directory
+	// initialSize != -1 only when overwriting files
+	sourceFolder, errSrc := c.User.GetVirtualFolderForPath(path.Dir(virtualSourcePath))
+	dstFolder, errDst := c.User.GetVirtualFolderForPath(path.Dir(virtualTargetPath))
+	if errSrc != nil && errDst != nil {
+		// both files are contained inside the user home dir
+		if initialSize != -1 {
+			// we cannot have a directory here
+			dataprovider.UpdateUserQuota(c.User, -1, -initialSize, false) //nolint:errcheck
+		}
+		return nil
+	}
+
+	filesSize := int64(0)
+	numFiles := 1
+	if fi, err := c.Fs.Stat(targetPath); err == nil {
+		if fi.Mode().IsDir() {
+			numFiles, filesSize, err = c.Fs.GetDirSize(targetPath)
+			if err != nil {
+				c.Log(logger.LevelWarn, "failed to update quota after rename, error scanning moved folder %#v: %v",
+					targetPath, err)
+				return err
+			}
+		} else {
+			filesSize = fi.Size()
+		}
+	} else {
+		c.Log(logger.LevelWarn, "failed to update quota after rename, file %#v stat error: %+v", targetPath, err)
+		return err
+	}
+	if errSrc == nil && errDst == nil {
+		c.updateQuotaMoveBetweenVFolders(sourceFolder, dstFolder, initialSize, filesSize, numFiles)
+	}
+	if errSrc == nil && errDst != nil {
+		c.updateQuotaMoveFromVFolder(sourceFolder, initialSize, filesSize, numFiles)
+	}
+	if errSrc != nil && errDst == nil {
+		c.updateQuotaMoveToVFolder(dstFolder, initialSize, filesSize, numFiles)
+	}
+	return nil
+}
+
+// GetPermissionDeniedError returns an appropriate permission denied error for the connection protocol
+func (c *BaseConnection) GetPermissionDeniedError() error {
+	switch c.protocol {
+	case ProtocolSFTP:
+		return sftp.ErrSSHFxPermissionDenied
+	case ProtocolWebDAV:
+		return os.ErrPermission
+	default:
+		return ErrPermissionDenied
+	}
+}
+
+// GetNotExistError returns an appropriate not exist error for the connection protocol
+func (c *BaseConnection) GetNotExistError() error {
+	switch c.protocol {
+	case ProtocolSFTP:
+		return sftp.ErrSSHFxNoSuchFile
+	case ProtocolWebDAV:
+		return os.ErrNotExist
+	default:
+		return ErrNotExist
+	}
+}
+
+// GetOpUnsupportedError returns an appropriate operation not supported error for the connection protocol
+func (c *BaseConnection) GetOpUnsupportedError() error {
+	switch c.protocol {
+	case ProtocolSFTP:
+		return sftp.ErrSSHFxOpUnsupported
+	default:
+		return ErrOpUnsupported
+	}
+}
+
+// GetGenericError returns an appropriate generic error for the connection protocol
+func (c *BaseConnection) GetGenericError(err error) error {
+	switch c.protocol {
+	case ProtocolSFTP:
+		return sftp.ErrSSHFxFailure
+	default:
+		if err == ErrPermissionDenied || err == ErrNotExist || err == ErrOpUnsupported || err == ErrQuotaExceeded {
+			return err
+		}
+		return ErrGenericFailure
+	}
+}
+
+// GetFsError converts a filesystem error to a protocol error
+func (c *BaseConnection) GetFsError(err error) error {
+	if c.Fs.IsNotExist(err) {
+		return c.GetNotExistError()
+	} else if c.Fs.IsPermission(err) {
+		return c.GetPermissionDeniedError()
+	} else if err != nil {
+		return c.GetGenericError(err)
+	}
+	return nil
+}

common/tlsutils.go

@@ -0,0 +1,54 @@
+package common
+
+import (
+	"crypto/tls"
+	"sync"
+
+	"github.com/drakkan/sftpgo/logger"
+)
+
+// CertManager defines a TLS certificate manager
+type CertManager struct {
+	certPath string
+	keyPath  string
+	sync.RWMutex
+	cert *tls.Certificate
+}
+
+// LoadCertificate loads the configured x509 key pair
+func (m *CertManager) LoadCertificate(logSender string) error {
+	newCert, err := tls.LoadX509KeyPair(m.certPath, m.keyPath)
+	if err != nil {
+		logger.Warn(logSender, "", "unable to load X509 key pair, cert file %#v key file %#v error: %v",
+			m.certPath, m.keyPath, err)
+		return err
+	}
+	logger.Debug(logSender, "", "TLS certificate %#v successfully loaded", m.certPath)
+	m.Lock()
+	defer m.Unlock()
+	m.cert = &newCert
+	return nil
+}
+
+// GetCertificateFunc returns the loaded certificate
+func (m *CertManager) GetCertificateFunc() func(*tls.ClientHelloInfo) (*tls.Certificate, error) {
+	return func(clientHello *tls.ClientHelloInfo) (*tls.Certificate, error) {
+		m.RLock()
+		defer m.RUnlock()
+		return m.cert, nil
+	}
+}
+
+// NewCertManager creates a new certificate manager
+func NewCertManager(certificateFile, certificateKeyFile, logSender string) (*CertManager, error) {
+	manager := &CertManager{
+		cert:     nil,
+		certPath: certificateFile,
+		keyPath:  certificateKeyFile,
+	}
+	err := manager.LoadCertificate(logSender)
+	if err != nil {
+		return nil, err
+	}
+	return manager, nil
+}

common/tlsutils_test.go

@@ -0,0 +1,69 @@
+package common
+
+import (
+	"crypto/tls"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+const (
+	httpsCert = `-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----`
+	httpsKey = `-----BEGIN EC PARAMETERS-----
+BgUrgQQAIg==
+-----END EC PARAMETERS-----
+-----BEGIN EC PRIVATE KEY-----
+MIGkAgEBBDCfMNsN6miEE3rVyUPwElfiJSWaR5huPCzUenZOfJT04GAcQdWvEju3
+UM2lmBLIXpGgBwYFK4EEACKhZANiAARCjRMqJ85rzMC998X5z761nJ+xL3bkmGVq
+WvrJ51t5OxV0v25NsOgR82CANXUgvhVYs7vNFN+jxtb2aj6Xg+/2G/BNxkaFspIV
+CzgWkxiz7XE4lgUwX44FCXZM3+JeUbI=
+-----END EC PRIVATE KEY-----`
+)
+
+func TestLoadCertificate(t *testing.T) {
+	certPath := filepath.Join(os.TempDir(), "test.crt")
+	keyPath := filepath.Join(os.TempDir(), "test.key")
+	err := ioutil.WriteFile(certPath, []byte(httpsCert), os.ModePerm)
+	assert.NoError(t, err)
+	err = ioutil.WriteFile(keyPath, []byte(httpsKey), os.ModePerm)
+	assert.NoError(t, err)
+	certManager, err := NewCertManager(certPath, keyPath, logSenderTest)
+	assert.NoError(t, err)
+	certFunc := certManager.GetCertificateFunc()
+	if assert.NotNil(t, certFunc) {
+		hello := &tls.ClientHelloInfo{
+			ServerName:   "localhost",
+			CipherSuites: []uint16{tls.TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305},
+		}
+		cert, err := certFunc(hello)
+		assert.NoError(t, err)
+		assert.Equal(t, certManager.cert, cert)
+	}
+
+	err = os.Remove(certPath)
+	assert.NoError(t, err)
+	err = os.Remove(keyPath)
+	assert.NoError(t, err)
+}
+
+func TestLoadInvalidCert(t *testing.T) {
+	certManager, err := NewCertManager("test.crt", "test.key", logSenderTest)
+	assert.Error(t, err)
+	assert.Nil(t, certManager)
+}

common/transfer.go

@@ -0,0 +1,290 @@
+package common
+
+import (
+	"errors"
+	"os"
+	"path"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"github.com/drakkan/sftpgo/dataprovider"
+	"github.com/drakkan/sftpgo/logger"
+	"github.com/drakkan/sftpgo/metrics"
+	"github.com/drakkan/sftpgo/vfs"
+)
+
+var (
+	// ErrTransferClosed defines the error returned for a closed transfer
+	ErrTransferClosed = errors.New("transfer already closed")
+)
+
+// BaseTransfer contains protocols common transfer details for an upload or a download.
+type BaseTransfer struct { //nolint:maligned
+	ID             uint64
+	Fs             vfs.Fs
+	File           *os.File
+	Connection     *BaseConnection
+	cancelFn       func()
+	fsPath         string
+	start          time.Time
+	transferType   int
+	MinWriteOffset int64
+	InitialSize    int64
+	isNewFile      bool
+	requestPath    string
+	BytesSent      int64
+	BytesReceived  int64
+	MaxWriteSize   int64
+	AbortTransfer  int32
+	sync.Mutex
+	ErrTransfer error
+}
+
+// NewBaseTransfer returns a new BaseTransfer and adds it to the given connection
+func NewBaseTransfer(file *os.File, conn *BaseConnection, cancelFn func(), fsPath, requestPath string, transferType int,
+	minWriteOffset, initialSize, maxWriteSize int64, isNewFile bool, fs vfs.Fs) *BaseTransfer {
+	t := &BaseTransfer{
+		ID:             conn.GetTransferID(),
+		File:           file,
+		Connection:     conn,
+		cancelFn:       cancelFn,
+		fsPath:         fsPath,
+		start:          time.Now(),
+		transferType:   transferType,
+		MinWriteOffset: minWriteOffset,
+		InitialSize:    initialSize,
+		isNewFile:      isNewFile,
+		requestPath:    requestPath,
+		BytesSent:      0,
+		BytesReceived:  0,
+		MaxWriteSize:   maxWriteSize,
+		AbortTransfer:  0,
+		Fs:             fs,
+	}
+
+	conn.AddTransfer(t)
+	return t
+}
+
+// GetID returns the transfer ID
+func (t *BaseTransfer) GetID() uint64 {
+	return t.ID
+}
+
+// GetType returns the transfer type
+func (t *BaseTransfer) GetType() int {
+	return t.transferType
+}
+
+// GetSize returns the transferred size
+func (t *BaseTransfer) GetSize() int64 {
+	if t.transferType == TransferDownload {
+		return atomic.LoadInt64(&t.BytesSent)
+	}
+	return atomic.LoadInt64(&t.BytesReceived)
+}
+
+// GetStartTime returns the start time
+func (t *BaseTransfer) GetStartTime() time.Time {
+	return t.start
+}
+
+// SignalClose signals that the transfer should be closed.
+// For same protocols, for example WebDAV, we have no
+// access to the network connection, so we use this method
+// to make the next read or write to fail
+func (t *BaseTransfer) SignalClose() {
+	atomic.StoreInt32(&(t.AbortTransfer), 1)
+}
+
+// GetVirtualPath returns the transfer virtual path
+func (t *BaseTransfer) GetVirtualPath() string {
+	return t.requestPath
+}
+
+// GetFsPath returns the transfer filesystem path
+func (t *BaseTransfer) GetFsPath() string {
+	return t.fsPath
+}
+
+// GetRealFsPath returns the real transfer filesystem path.
+// If atomic uploads are enabled this differ from fsPath
+func (t *BaseTransfer) GetRealFsPath(fsPath string) string {
+	if fsPath == t.GetFsPath() {
+		if t.File != nil {
+			return t.File.Name()
+		}
+		return t.fsPath
+	}
+	return ""
+}
+
+// SetCancelFn sets the cancel function for the transfer
+func (t *BaseTransfer) SetCancelFn(cancelFn func()) {
+	t.cancelFn = cancelFn
+}
+
+// Truncate changes the size of the opened file.
+// Supported for local fs only
+func (t *BaseTransfer) Truncate(fsPath string, size int64) (int64, error) {
+	if fsPath == t.GetFsPath() {
+		if t.File != nil {
+			initialSize := t.InitialSize
+			err := t.File.Truncate(size)
+			if err == nil {
+				t.Lock()
+				t.InitialSize = size
+				if t.MaxWriteSize > 0 {
+					sizeDiff := initialSize - size
+					t.MaxWriteSize += sizeDiff
+					metrics.TransferCompleted(atomic.LoadInt64(&t.BytesSent), atomic.LoadInt64(&t.BytesReceived), t.transferType, t.ErrTransfer)
+					atomic.StoreInt64(&t.BytesReceived, 0)
+				}
+				t.Unlock()
+			}
+			t.Connection.Log(logger.LevelDebug, "file %#v truncated to size %v max write size %v new initial size %v err: %v",
+				fsPath, size, t.MaxWriteSize, t.InitialSize, err)
+			return initialSize, err
+		}
+		if size == 0 && atomic.LoadInt64(&t.BytesSent) == 0 {
+			// for cloud providers the file is always truncated to zero, we don't support append/resume for uploads
+			return 0, nil
+		}
+		return 0, ErrOpUnsupported
+	}
+	return 0, errTransferMismatch
+}
+
+// TransferError is called if there is an unexpected error.
+// For example network or client issues
+func (t *BaseTransfer) TransferError(err error) {
+	t.Lock()
+	defer t.Unlock()
+	if t.ErrTransfer != nil {
+		return
+	}
+	t.ErrTransfer = err
+	if t.cancelFn != nil {
+		t.cancelFn()
+	}
+	elapsed := time.Since(t.start).Nanoseconds() / 1000000
+	t.Connection.Log(logger.LevelWarn, "Unexpected error for transfer, path: %#v, error: \"%v\" bytes sent: %v, "+
+		"bytes received: %v transfer running since %v ms", t.fsPath, t.ErrTransfer, atomic.LoadInt64(&t.BytesSent),
+		atomic.LoadInt64(&t.BytesReceived), elapsed)
+}
+
+// Close it is called when the transfer is completed.
+// It logs the transfer info, updates the user quota (for uploads)
+// and executes any defined action.
+// If there is an error no action will be executed and, in atomic mode,
+// we try to delete the temporary file
+func (t *BaseTransfer) Close() error {
+	defer t.Connection.RemoveTransfer(t)
+
+	var err error
+	numFiles := 0
+	if t.isNewFile {
+		numFiles = 1
+	}
+	metrics.TransferCompleted(atomic.LoadInt64(&t.BytesSent), atomic.LoadInt64(&t.BytesReceived), t.transferType, t.ErrTransfer)
+	if t.ErrTransfer == ErrQuotaExceeded && t.File != nil {
+		// if quota is exceeded we try to remove the partial file for uploads to local filesystem
+		err = os.Remove(t.File.Name())
+		if err == nil {
+			numFiles--
+			atomic.StoreInt64(&t.BytesReceived, 0)
+			t.MinWriteOffset = 0
+		}
+		t.Connection.Log(logger.LevelWarn, "upload denied due to space limit, delete temporary file: %#v, deletion error: %v",
+			t.File.Name(), err)
+	} else if t.transferType == TransferUpload && t.File != nil && t.File.Name() != t.fsPath {
+		if t.ErrTransfer == nil || Config.UploadMode == UploadModeAtomicWithResume {
+			err = os.Rename(t.File.Name(), t.fsPath)
+			t.Connection.Log(logger.LevelDebug, "atomic upload completed, rename: %#v -> %#v, error: %v",
+				t.File.Name(), t.fsPath, err)
+		} else {
+			err = os.Remove(t.File.Name())
+			t.Connection.Log(logger.LevelWarn, "atomic upload completed with error: \"%v\", delete temporary file: %#v, "+
+				"deletion error: %v", t.ErrTransfer, t.File.Name(), err)
+			if err == nil {
+				numFiles--
+				atomic.StoreInt64(&t.BytesReceived, 0)
+				t.MinWriteOffset = 0
+			}
+		}
+	}
+	elapsed := time.Since(t.start).Nanoseconds() / 1000000
+	if t.transferType == TransferDownload {
+		logger.TransferLog(downloadLogSender, t.fsPath, elapsed, atomic.LoadInt64(&t.BytesSent), t.Connection.User.Username,
+			t.Connection.ID, t.Connection.protocol)
+		action := newActionNotification(&t.Connection.User, operationDownload, t.fsPath, "", "", t.Connection.protocol,
+			atomic.LoadInt64(&t.BytesSent), t.ErrTransfer)
+		go action.execute() //nolint:errcheck
+	} else {
+		fileSize := atomic.LoadInt64(&t.BytesReceived) + t.MinWriteOffset
+		info, err := t.Fs.Stat(t.fsPath)
+		if err == nil {
+			fileSize = info.Size()
+		}
+		t.Connection.Log(logger.LevelDebug, "upload file size %v stat error %v", fileSize, err)
+		t.updateQuota(numFiles, fileSize)
+		logger.TransferLog(uploadLogSender, t.fsPath, elapsed, atomic.LoadInt64(&t.BytesReceived), t.Connection.User.Username,
+			t.Connection.ID, t.Connection.protocol)
+		action := newActionNotification(&t.Connection.User, operationUpload, t.fsPath, "", "", t.Connection.protocol,
+			fileSize, t.ErrTransfer)
+		go action.execute() //nolint:errcheck
+	}
+	if t.ErrTransfer != nil {
+		t.Connection.Log(logger.LevelWarn, "transfer error: %v, path: %#v", t.ErrTransfer, t.fsPath)
+		if err == nil {
+			err = t.ErrTransfer
+		}
+	}
+	return err
+}
+
+func (t *BaseTransfer) updateQuota(numFiles int, fileSize int64) bool {
+	// S3 uploads are atomic, if there is an error nothing is uploaded
+	if t.File == nil && t.ErrTransfer != nil {
+		return false
+	}
+	sizeDiff := fileSize - t.InitialSize
+	if t.transferType == TransferUpload && (numFiles != 0 || sizeDiff > 0) {
+		vfolder, err := t.Connection.User.GetVirtualFolderForPath(path.Dir(t.requestPath))
+		if err == nil {
+			dataprovider.UpdateVirtualFolderQuota(vfolder.BaseVirtualFolder, numFiles, //nolint:errcheck
+				sizeDiff, false)
+			if vfolder.IsIncludedInUserQuota() {
+				dataprovider.UpdateUserQuota(t.Connection.User, numFiles, sizeDiff, false) //nolint:errcheck
+			}
+		} else {
+			dataprovider.UpdateUserQuota(t.Connection.User, numFiles, sizeDiff, false) //nolint:errcheck
+		}
+		return true
+	}
+	return false
+}
+
+// HandleThrottle manage bandwidth throttling
+func (t *BaseTransfer) HandleThrottle() {
+	var wantedBandwidth int64
+	var trasferredBytes int64
+	if t.transferType == TransferDownload {
+		wantedBandwidth = t.Connection.User.DownloadBandwidth
+		trasferredBytes = atomic.LoadInt64(&t.BytesSent)
+	} else {
+		wantedBandwidth = t.Connection.User.UploadBandwidth
+		trasferredBytes = atomic.LoadInt64(&t.BytesReceived)
+	}
+	if wantedBandwidth > 0 {
+		// real and wanted elapsed as milliseconds, bytes as kilobytes
+		realElapsed := time.Since(t.start).Nanoseconds() / 1000000
+		// trasferredBytes / 1000 = KB/s, we multiply for 1000 to get milliseconds
+		wantedElapsed := 1000 * (trasferredBytes / 1000) / wantedBandwidth
+		if wantedElapsed > realElapsed {
+			toSleep := time.Duration(wantedElapsed - realElapsed)
+			time.Sleep(toSleep * time.Millisecond)
+		}
+	}
+}

common/transfer_test.go

@@ -0,0 +1,254 @@
+package common
+
+import (
+	"errors"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"github.com/drakkan/sftpgo/dataprovider"
+	"github.com/drakkan/sftpgo/vfs"
+)
+
+func TestTransferUpdateQuota(t *testing.T) {
+	conn := NewBaseConnection("", ProtocolSFTP, dataprovider.User{}, nil)
+	transfer := BaseTransfer{
+		Connection:    conn,
+		transferType:  TransferUpload,
+		BytesReceived: 123,
+		Fs:            vfs.NewOsFs("", os.TempDir(), nil),
+	}
+	errFake := errors.New("fake error")
+	transfer.TransferError(errFake)
+	assert.False(t, transfer.updateQuota(1, 0))
+	err := transfer.Close()
+	if assert.Error(t, err) {
+		assert.EqualError(t, err, errFake.Error())
+	}
+	mappedPath := filepath.Join(os.TempDir(), "vdir")
+	vdirPath := "/vdir"
+	conn.User.VirtualFolders = append(conn.User.VirtualFolders, vfs.VirtualFolder{
+		BaseVirtualFolder: vfs.BaseVirtualFolder{
+			MappedPath: mappedPath,
+		},
+		VirtualPath: vdirPath,
+		QuotaFiles:  -1,
+		QuotaSize:   -1,
+	})
+	transfer.ErrTransfer = nil
+	transfer.BytesReceived = 1
+	transfer.requestPath = "/vdir/file"
+	assert.True(t, transfer.updateQuota(1, 0))
+	err = transfer.Close()
+	assert.NoError(t, err)
+}
+
+func TestTransferThrottling(t *testing.T) {
+	u := dataprovider.User{
+		Username:          "test",
+		UploadBandwidth:   50,
+		DownloadBandwidth: 40,
+	}
+	fs := vfs.NewOsFs("", os.TempDir(), nil)
+	testFileSize := int64(131072)
+	wantedUploadElapsed := 1000 * (testFileSize / 1000) / u.UploadBandwidth
+	wantedDownloadElapsed := 1000 * (testFileSize / 1000) / u.DownloadBandwidth
+	// some tolerance
+	wantedUploadElapsed -= wantedDownloadElapsed / 10
+	wantedDownloadElapsed -= wantedDownloadElapsed / 10
+	conn := NewBaseConnection("id", ProtocolSCP, u, nil)
+	transfer := NewBaseTransfer(nil, conn, nil, "", "", TransferUpload, 0, 0, 0, true, fs)
+	transfer.BytesReceived = testFileSize
+	transfer.Connection.UpdateLastActivity()
+	startTime := transfer.Connection.GetLastActivity()
+	transfer.HandleThrottle()
+	elapsed := time.Since(startTime).Nanoseconds() / 1000000
+	assert.GreaterOrEqual(t, elapsed, wantedUploadElapsed, "upload bandwidth throttling not respected")
+	err := transfer.Close()
+	assert.NoError(t, err)
+
+	transfer = NewBaseTransfer(nil, conn, nil, "", "", TransferDownload, 0, 0, 0, true, fs)
+	transfer.BytesSent = testFileSize
+	transfer.Connection.UpdateLastActivity()
+	startTime = transfer.Connection.GetLastActivity()
+
+	transfer.HandleThrottle()
+	elapsed = time.Since(startTime).Nanoseconds() / 1000000
+	assert.GreaterOrEqual(t, elapsed, wantedDownloadElapsed, "download bandwidth throttling not respected")
+	err = transfer.Close()
+	assert.NoError(t, err)
+}
+
+func TestRealPath(t *testing.T) {
+	testFile := filepath.Join(os.TempDir(), "afile.txt")
+	fs := vfs.NewOsFs("123", os.TempDir(), nil)
+	u := dataprovider.User{
+		Username: "user",
+		HomeDir:  os.TempDir(),
+	}
+	u.Permissions = make(map[string][]string)
+	u.Permissions["/"] = []string{dataprovider.PermAny}
+	file, err := os.Create(testFile)
+	require.NoError(t, err)
+	conn := NewBaseConnection(fs.ConnectionID(), ProtocolSFTP, u, fs)
+	transfer := NewBaseTransfer(file, conn, nil, testFile, "/transfer_test_file", TransferUpload, 0, 0, 0, true, fs)
+	rPath := transfer.GetRealFsPath(testFile)
+	assert.Equal(t, testFile, rPath)
+	rPath = conn.getRealFsPath(testFile)
+	assert.Equal(t, testFile, rPath)
+	err = transfer.Close()
+	assert.NoError(t, err)
+	err = file.Close()
+	assert.NoError(t, err)
+	transfer.File = nil
+	rPath = transfer.GetRealFsPath(testFile)
+	assert.Equal(t, testFile, rPath)
+	rPath = transfer.GetRealFsPath("")
+	assert.Empty(t, rPath)
+	err = os.Remove(testFile)
+	assert.NoError(t, err)
+	assert.Len(t, conn.GetTransfers(), 0)
+}
+
+func TestTruncate(t *testing.T) {
+	testFile := filepath.Join(os.TempDir(), "transfer_test_file")
+	fs := vfs.NewOsFs("123", os.TempDir(), nil)
+	u := dataprovider.User{
+		Username: "user",
+		HomeDir:  os.TempDir(),
+	}
+	u.Permissions = make(map[string][]string)
+	u.Permissions["/"] = []string{dataprovider.PermAny}
+	file, err := os.Create(testFile)
+	if !assert.NoError(t, err) {
+		assert.FailNow(t, "unable to open test file")
+	}
+	_, err = file.Write([]byte("hello"))
+	assert.NoError(t, err)
+	conn := NewBaseConnection(fs.ConnectionID(), ProtocolSFTP, u, fs)
+	transfer := NewBaseTransfer(file, conn, nil, testFile, "/transfer_test_file", TransferUpload, 0, 5, 100, false, fs)
+
+	err = conn.SetStat(testFile, "/transfer_test_file", &StatAttributes{
+		Size:  2,
+		Flags: StatAttrSize,
+	})
+	assert.NoError(t, err)
+	assert.Equal(t, int64(103), transfer.MaxWriteSize)
+	err = transfer.Close()
+	assert.NoError(t, err)
+	err = file.Close()
+	assert.NoError(t, err)
+	fi, err := os.Stat(testFile)
+	if assert.NoError(t, err) {
+		assert.Equal(t, int64(2), fi.Size())
+	}
+
+	transfer = NewBaseTransfer(file, conn, nil, testFile, "/transfer_test_file", TransferUpload, 0, 0, 100, true, fs)
+	// file.Stat will fail on a closed file
+	err = conn.SetStat(testFile, "/transfer_test_file", &StatAttributes{
+		Size:  2,
+		Flags: StatAttrSize,
+	})
+	assert.Error(t, err)
+	err = transfer.Close()
+	assert.NoError(t, err)
+
+	transfer = NewBaseTransfer(nil, conn, nil, testFile, "", TransferUpload, 0, 0, 0, true, fs)
+	_, err = transfer.Truncate("mismatch", 0)
+	assert.EqualError(t, err, errTransferMismatch.Error())
+	_, err = transfer.Truncate(testFile, 0)
+	assert.NoError(t, err)
+	_, err = transfer.Truncate(testFile, 1)
+	assert.EqualError(t, err, ErrOpUnsupported.Error())
+
+	err = transfer.Close()
+	assert.NoError(t, err)
+
+	err = os.Remove(testFile)
+	assert.NoError(t, err)
+
+	assert.Len(t, conn.GetTransfers(), 0)
+}
+
+func TestTransferErrors(t *testing.T) {
+	isCancelled := false
+	cancelFn := func() {
+		isCancelled = true
+	}
+	testFile := filepath.Join(os.TempDir(), "transfer_test_file")
+	fs := vfs.NewOsFs("id", os.TempDir(), nil)
+	u := dataprovider.User{
+		Username: "test",
+		HomeDir:  os.TempDir(),
+	}
+	err := ioutil.WriteFile(testFile, []byte("test data"), os.ModePerm)
+	assert.NoError(t, err)
+	file, err := os.Open(testFile)
+	if !assert.NoError(t, err) {
+		assert.FailNow(t, "unable to open test file")
+	}
+	conn := NewBaseConnection("id", ProtocolSFTP, u, fs)
+	transfer := NewBaseTransfer(file, conn, nil, testFile, "/transfer_test_file", TransferUpload, 0, 0, 0, true, fs)
+	assert.Nil(t, transfer.cancelFn)
+	assert.Equal(t, testFile, transfer.GetFsPath())
+	transfer.SetCancelFn(cancelFn)
+	errFake := errors.New("err fake")
+	transfer.BytesReceived = 9
+	transfer.TransferError(ErrQuotaExceeded)
+	assert.True(t, isCancelled)
+	transfer.TransferError(errFake)
+	assert.Error(t, transfer.ErrTransfer, ErrQuotaExceeded.Error())
+	// the file is closed from the embedding struct before to call close
+	err = file.Close()
+	assert.NoError(t, err)
+	err = transfer.Close()
+	if assert.Error(t, err) {
+		assert.Error(t, err, ErrQuotaExceeded.Error())
+	}
+	assert.NoFileExists(t, testFile)
+
+	err = ioutil.WriteFile(testFile, []byte("test data"), os.ModePerm)
+	assert.NoError(t, err)
+	file, err = os.Open(testFile)
+	if !assert.NoError(t, err) {
+		assert.FailNow(t, "unable to open test file")
+	}
+	fsPath := filepath.Join(os.TempDir(), "test_file")
+	transfer = NewBaseTransfer(file, conn, nil, fsPath, "/test_file", TransferUpload, 0, 0, 0, true, fs)
+	transfer.BytesReceived = 9
+	transfer.TransferError(errFake)
+	assert.Error(t, transfer.ErrTransfer, errFake.Error())
+	// the file is closed from the embedding struct before to call close
+	err = file.Close()
+	assert.NoError(t, err)
+	err = transfer.Close()
+	if assert.Error(t, err) {
+		assert.Error(t, err, errFake.Error())
+	}
+	assert.NoFileExists(t, testFile)
+
+	err = ioutil.WriteFile(testFile, []byte("test data"), os.ModePerm)
+	assert.NoError(t, err)
+	file, err = os.Open(testFile)
+	if !assert.NoError(t, err) {
+		assert.FailNow(t, "unable to open test file")
+	}
+	transfer = NewBaseTransfer(file, conn, nil, fsPath, "/test_file", TransferUpload, 0, 0, 0, true, fs)
+	transfer.BytesReceived = 9
+	// the file is closed from the embedding struct before to call close
+	err = file.Close()
+	assert.NoError(t, err)
+	err = transfer.Close()
+	assert.NoError(t, err)
+	assert.NoFileExists(t, testFile)
+	assert.FileExists(t, fsPath)
+	err = os.Remove(fsPath)
+	assert.NoError(t, err)
+
+	assert.Len(t, conn.GetTransfers(), 0)
+}

config/config.go

@@ -1,20 +1,22 @@
-// Package config manages the configuration.
-// Configuration is loaded from sftpgo.conf file.
-// If sftpgo.conf is not found or cannot be readed or decoded as json the default configuration is used.
-// The default configuration an be found inside the source tree:
-// https://github.com/drakkan/sftpgo/blob/master/sftpgo.conf
+// Package config manages the configuration
 package config
 
 import (
 	"fmt"
 	"strings"
 
+	"github.com/spf13/viper"
+
+	"github.com/drakkan/sftpgo/common"
 	"github.com/drakkan/sftpgo/dataprovider"
+	"github.com/drakkan/sftpgo/ftpd"
+	"github.com/drakkan/sftpgo/httpclient"
 	"github.com/drakkan/sftpgo/httpd"
 	"github.com/drakkan/sftpgo/logger"
 	"github.com/drakkan/sftpgo/sftpd"
 	"github.com/drakkan/sftpgo/utils"
-	"github.com/spf13/viper"
+	"github.com/drakkan/sftpgo/version"
+	"github.com/drakkan/sftpgo/webdavd"
 )
 
 const (
@@ -28,39 +30,83 @@ const (
 )
 
 var (
-	globalConf    globalConfig
-	defaultBanner = fmt.Sprintf("SFTPGo_%v", utils.GetAppVersion().Version)
+	globalConf         globalConfig
+	defaultSFTPDBanner = fmt.Sprintf("SFTPGo_%v", version.Get().Version)
+	defaultFTPDBanner  = fmt.Sprintf("SFTPGo %v ready", version.Get().Version)
 )
 
 type globalConfig struct {
-	SFTPD        sftpd.Configuration `json:"sftpd" mapstructure:"sftpd"`
-	ProviderConf dataprovider.Config `json:"data_provider" mapstructure:"data_provider"`
-	HTTPDConfig  httpd.Conf          `json:"httpd" mapstructure:"httpd"`
+	Common       common.Configuration  `json:"common" mapstructure:"common"`
+	SFTPD        sftpd.Configuration   `json:"sftpd" mapstructure:"sftpd"`
+	FTPD         ftpd.Configuration    `json:"ftpd" mapstructure:"ftpd"`
+	WebDAVD      webdavd.Configuration `json:"webdavd" mapstructure:"webdavd"`
+	ProviderConf dataprovider.Config   `json:"data_provider" mapstructure:"data_provider"`
+	HTTPDConfig  httpd.Conf            `json:"httpd" mapstructure:"httpd"`
+	HTTPConfig   httpclient.Config     `json:"http" mapstructure:"http"`
 }
 
 func init() {
 	// create a default configuration to use if no config file is provided
 	globalConf = globalConfig{
-		SFTPD: sftpd.Configuration{
-			Banner:       defaultBanner,
-			BindPort:     2022,
-			BindAddress:  "",
-			IdleTimeout:  15,
-			MaxAuthTries: 0,
-			Umask:        "0022",
-			UploadMode:   0,
-			Actions: sftpd.Actions{
-				ExecuteOn:           []string{},
-				Command:             "",
-				HTTPNotificationURL: "",
+		Common: common.Configuration{
+			IdleTimeout: 15,
+			UploadMode:  0,
+			Actions: common.ProtocolActions{
+				ExecuteOn: []string{},
+				Hook:      "",
+			},
+			SetstatMode:   0,
+			ProxyProtocol: 0,
+			ProxyAllowed:  []string{},
+		},
+		SFTPD: sftpd.Configuration{
+			Banner:                  defaultSFTPDBanner,
+			BindPort:                2022,
+			BindAddress:             "",
+			MaxAuthTries:            0,
+			HostKeys:                []string{},
+			KexAlgorithms:           []string{},
+			Ciphers:                 []string{},
+			MACs:                    []string{},
+			TrustedUserCAKeys:       []string{},
+			LoginBannerFile:         "",
+			EnabledSSHCommands:      sftpd.GetDefaultSSHCommands(),
+			KeyboardInteractiveHook: "",
+			PasswordAuthentication:  true,
+		},
+		FTPD: ftpd.Configuration{
+			BindPort:                 0,
+			BindAddress:              "",
+			Banner:                   defaultFTPDBanner,
+			BannerFile:               "",
+			ActiveTransfersPortNon20: false,
+			ForcePassiveIP:           "",
+			PassivePortRange: ftpd.PortRange{
+				Start: 50000,
+				End:   50100,
+			},
+			CertificateFile:    "",
+			CertificateKeyFile: "",
+		},
+		WebDAVD: webdavd.Configuration{
+			BindPort:           0,
+			BindAddress:        "",
+			CertificateFile:    "",
+			CertificateKeyFile: "",
+			Cors: webdavd.Cors{
+				Enabled:          false,
+				AllowedOrigins:   []string{},
+				AllowedMethods:   []string{},
+				AllowedHeaders:   []string{},
+				ExposedHeaders:   []string{},
+				AllowCredentials: false,
+				MaxAge:           0,
+			},
+			Cache: webdavd.Cache{
+				Enabled:        true,
+				ExpirationTime: 0,
+				MaxSize:        50,
 			},
-			Keys:               []sftpd.Key{},
-			IsSCPEnabled:       false,
-			KexAlgorithms:      []string{},
-			Ciphers:            []string{},
-			MACs:               []string{},
-			LoginBannerFile:    "",
-			EnabledSSHCommands: sftpd.GetDefaultSSHCommands(),
 		},
 		ProviderConf: dataprovider.Config{
 			Driver:           "sqlite",
@@ -70,26 +116,47 @@ func init() {
 			Username:         "",
 			Password:         "",
 			ConnectionString: "",
-			UsersTable:       "users",
+			SQLTablesPrefix:  "",
 			ManageUsers:      1,
 			SSLMode:          0,
 			TrackQuota:       1,
 			PoolSize:         0,
 			UsersBaseDir:     "",
-			Actions: dataprovider.Actions{
-				ExecuteOn:           []string{},
-				Command:             "",
-				HTTPNotificationURL: "",
+			Actions: dataprovider.UserActions{
+				ExecuteOn: []string{},
+				Hook:      "",
 			},
-			ExternalAuthProgram: "",
-			ExternalAuthScope:   0,
+			ExternalAuthHook:   "",
+			ExternalAuthScope:  0,
+			CredentialsPath:    "credentials",
+			PreLoginHook:       "",
+			PostLoginHook:      "",
+			PostLoginScope:     0,
+			CheckPasswordHook:  "",
+			CheckPasswordScope: 0,
+			PasswordHashing: dataprovider.PasswordHashing{
+				Argon2Options: dataprovider.Argon2Options{
+					Memory:      65536,
+					Iterations:  1,
+					Parallelism: 2,
+				},
+			},
+			UpdateMode: 0,
 		},
 		HTTPDConfig: httpd.Conf{
-			BindPort:        8080,
-			BindAddress:     "127.0.0.1",
-			TemplatesPath:   "templates",
-			StaticFilesPath: "static",
-			BackupsPath:     "backups",
+			BindPort:           8080,
+			BindAddress:        "127.0.0.1",
+			TemplatesPath:      "templates",
+			StaticFilesPath:    "static",
+			BackupsPath:        "backups",
+			AuthUserFile:       "",
+			CertificateFile:    "",
+			CertificateKeyFile: "",
+		},
+		HTTPConfig: httpclient.Config{
+			Timeout:        20,
+			CACertificates: nil,
+			SkipTLSVerify:  false,
 		},
 	}
 
@@ -101,6 +168,16 @@ func init() {
 	viper.AllowEmptyEnv(true)
 }
 
+// GetCommonConfig returns the common protocols configuration
+func GetCommonConfig() common.Configuration {
+	return globalConf.Common
+}
+
+// SetCommonConfig sets the common protocols configuration
+func SetCommonConfig(config common.Configuration) {
+	globalConf.Common = config
+}
+
 // GetSFTPDConfig returns the configuration for the SFTP server
 func GetSFTPDConfig() sftpd.Configuration {
 	return globalConf.SFTPD
@@ -111,6 +188,26 @@ func SetSFTPDConfig(config sftpd.Configuration) {
 	globalConf.SFTPD = config
 }
 
+// GetFTPDConfig returns the configuration for the FTP server
+func GetFTPDConfig() ftpd.Configuration {
+	return globalConf.FTPD
+}
+
+// SetFTPDConfig sets the configuration for the FTP server
+func SetFTPDConfig(config ftpd.Configuration) {
+	globalConf.FTPD = config
+}
+
+// GetWebDAVDConfig returns the configuration for the WebDAV server
+func GetWebDAVDConfig() webdavd.Configuration {
+	return globalConf.WebDAVD
+}
+
+// SetWebDAVDConfig sets the configuration for the WebDAV server
+func SetWebDAVDConfig(config webdavd.Configuration) {
+	globalConf.WebDAVD = config
+}
+
 // GetHTTPDConfig returns the configuration for the HTTP server
 func GetHTTPDConfig() httpd.Conf {
 	return globalConf.HTTPDConfig
@@ -131,6 +228,11 @@ func SetProviderConf(config dataprovider.Config) {
 	globalConf.ProviderConf = config
 }
 
+// GetHTTPConfig returns the configuration for HTTP clients
+func GetHTTPConfig() httpclient.Config {
+	return globalConf.HTTPConfig
+}
+
 func getRedactedGlobalConf() globalConfig {
 	conf := globalConf
 	conf.ProviderConf.Password = "[redacted]"
@@ -161,22 +263,88 @@ func LoadConfig(configDir, configName string) error {
 		logger.WarnToConsole("error parsing configuration file: %v. Default configuration will be used.", err)
 		return err
 	}
+	checkCommonParamsCompatibility()
 	if strings.TrimSpace(globalConf.SFTPD.Banner) == "" {
-		globalConf.SFTPD.Banner = defaultBanner
+		globalConf.SFTPD.Banner = defaultSFTPDBanner
 	}
-	if globalConf.SFTPD.UploadMode < 0 || globalConf.SFTPD.UploadMode > 2 {
-		err = fmt.Errorf("invalid upload_mode 0 and 1 are supported, configured: %v reset upload_mode to 0",
-			globalConf.SFTPD.UploadMode)
-		globalConf.SFTPD.UploadMode = 0
+	if strings.TrimSpace(globalConf.FTPD.Banner) == "" {
+		globalConf.FTPD.Banner = defaultFTPDBanner
+	}
+	if len(globalConf.ProviderConf.UsersBaseDir) > 0 && !utils.IsFileInputValid(globalConf.ProviderConf.UsersBaseDir) {
+		err = fmt.Errorf("invalid users base dir %#v will be ignored", globalConf.ProviderConf.UsersBaseDir)
+		globalConf.ProviderConf.UsersBaseDir = ""
 		logger.Warn(logSender, "", "Configuration error: %v", err)
 		logger.WarnToConsole("Configuration error: %v", err)
 	}
-	if globalConf.ProviderConf.ExternalAuthScope < 0 || globalConf.ProviderConf.ExternalAuthScope > 2 {
+	if globalConf.Common.UploadMode < 0 || globalConf.Common.UploadMode > 2 {
+		err = fmt.Errorf("invalid upload_mode 0, 1 and 2 are supported, configured: %v reset upload_mode to 0",
+			globalConf.Common.UploadMode)
+		globalConf.Common.UploadMode = 0
+		logger.Warn(logSender, "", "Configuration error: %v", err)
+		logger.WarnToConsole("Configuration error: %v", err)
+	}
+	if globalConf.Common.ProxyProtocol < 0 || globalConf.Common.ProxyProtocol > 2 {
+		err = fmt.Errorf("invalid proxy_protocol 0, 1 and 2 are supported, configured: %v reset proxy_protocol to 0",
+			globalConf.Common.ProxyProtocol)
+		globalConf.Common.ProxyProtocol = 0
+		logger.Warn(logSender, "", "Configuration error: %v", err)
+		logger.WarnToConsole("Configuration error: %v", err)
+	}
+	if globalConf.ProviderConf.ExternalAuthScope < 0 || globalConf.ProviderConf.ExternalAuthScope > 7 {
 		err = fmt.Errorf("invalid external_auth_scope: %v reset to 0", globalConf.ProviderConf.ExternalAuthScope)
 		globalConf.ProviderConf.ExternalAuthScope = 0
 		logger.Warn(logSender, "", "Configuration error: %v", err)
 		logger.WarnToConsole("Configuration error: %v", err)
 	}
-	logger.Debug(logSender, "", "config file used: '%v', config loaded: %+v", viper.ConfigFileUsed(), getRedactedGlobalConf())
+	if len(globalConf.ProviderConf.CredentialsPath) == 0 {
+		err = fmt.Errorf("invalid credentials path, reset to \"credentials\"")
+		globalConf.ProviderConf.CredentialsPath = "credentials"
+		logger.Warn(logSender, "", "Configuration error: %v", err)
+		logger.WarnToConsole("Configuration error: %v", err)
+	}
+	checkHostKeyCompatibility()
+	logger.Debug(logSender, "", "config file used: '%#v', config loaded: %+v", viper.ConfigFileUsed(), getRedactedGlobalConf())
 	return err
 }
+
+func checkHostKeyCompatibility() {
+	// we copy deprecated fields to new ones to keep backward compatibility so lint is disabled
+	if len(globalConf.SFTPD.Keys) > 0 && len(globalConf.SFTPD.HostKeys) == 0 { //nolint:staticcheck
+		logger.Warn(logSender, "", "keys is deprecated, please use host_keys")
+		logger.WarnToConsole("keys is deprecated, please use host_keys")
+		for _, k := range globalConf.SFTPD.Keys { //nolint:staticcheck
+			globalConf.SFTPD.HostKeys = append(globalConf.SFTPD.HostKeys, k.PrivateKey)
+		}
+	}
+}
+
+func checkCommonParamsCompatibility() {
+	// we copy deprecated fields to new ones to keep backward compatibility so lint is disabled
+	if globalConf.SFTPD.IdleTimeout > 0 { //nolint:staticcheck
+		logger.Warn(logSender, "", "sftpd.idle_timeout is deprecated, please use common.idle_timeout")
+		logger.WarnToConsole("sftpd.idle_timeout is deprecated, please use common.idle_timeout")
+		globalConf.Common.IdleTimeout = globalConf.SFTPD.IdleTimeout //nolint:staticcheck
+	}
+	if len(globalConf.SFTPD.Actions.Hook) > 0 && len(globalConf.Common.Actions.Hook) == 0 { //nolint:staticcheck
+		logger.Warn(logSender, "", "sftpd.actions is deprecated, please use common.actions")
+		logger.WarnToConsole("sftpd.actions is deprecated, please use common.actions")
+		globalConf.Common.Actions.ExecuteOn = globalConf.SFTPD.Actions.ExecuteOn //nolint:staticcheck
+		globalConf.Common.Actions.Hook = globalConf.SFTPD.Actions.Hook           //nolint:staticcheck
+	}
+	if globalConf.SFTPD.SetstatMode > 0 && globalConf.Common.SetstatMode == 0 { //nolint:staticcheck
+		logger.Warn(logSender, "", "sftpd.setstat_mode is deprecated, please use common.setstat_mode")
+		logger.WarnToConsole("sftpd.setstat_mode is deprecated, please use common.setstat_mode")
+		globalConf.Common.SetstatMode = globalConf.SFTPD.SetstatMode //nolint:staticcheck
+	}
+	if globalConf.SFTPD.UploadMode > 0 && globalConf.Common.UploadMode == 0 { //nolint:staticcheck
+		logger.Warn(logSender, "", "sftpd.upload_mode is deprecated, please use common.upload_mode")
+		logger.WarnToConsole("sftpd.upload_mode is deprecated, please use common.upload_mode")
+		globalConf.Common.UploadMode = globalConf.SFTPD.UploadMode //nolint:staticcheck
+	}
+	if globalConf.SFTPD.ProxyProtocol > 0 && globalConf.Common.ProxyProtocol == 0 { //nolint:staticcheck
+		logger.Warn(logSender, "", "sftpd.proxy_protocol is deprecated, please use common.proxy_protocol")
+		logger.WarnToConsole("sftpd.proxy_protocol is deprecated, please use common.proxy_protocol")
+		globalConf.Common.ProxyProtocol = globalConf.SFTPD.ProxyProtocol //nolint:staticcheck
+		globalConf.Common.ProxyAllowed = globalConf.SFTPD.ProxyAllowed   //nolint:staticcheck
+	}
+}

config/config_test.go

@@ -8,134 +8,275 @@ import (
 	"strings"
 	"testing"
 
+	"github.com/stretchr/testify/assert"
+
+	"github.com/drakkan/sftpgo/common"
 	"github.com/drakkan/sftpgo/config"
 	"github.com/drakkan/sftpgo/dataprovider"
+	"github.com/drakkan/sftpgo/ftpd"
+	"github.com/drakkan/sftpgo/httpclient"
 	"github.com/drakkan/sftpgo/httpd"
 	"github.com/drakkan/sftpgo/sftpd"
+	"github.com/drakkan/sftpgo/utils"
 )
 
 const (
 	tempConfigName = "temp"
+	configName     = "sftpgo"
 )
 
 func TestLoadConfigTest(t *testing.T) {
 	configDir := ".."
-	err := config.LoadConfig(configDir, "")
-	if err != nil {
-		t.Errorf("error loading config")
-	}
-	emptyHTTPDConf := httpd.Conf{}
-	if config.GetHTTPDConfig() == emptyHTTPDConf {
-		t.Errorf("error loading httpd conf")
-	}
-	emptyProviderConf := dataprovider.Config{}
-	if config.GetProviderConf().Driver == emptyProviderConf.Driver {
-		t.Errorf("error loading provider conf")
-	}
-	emptySFTPDConf := sftpd.Configuration{}
-	if config.GetSFTPDConfig().BindPort == emptySFTPDConf.BindPort {
-		t.Errorf("error loading SFTPD conf")
-	}
+	err := config.LoadConfig(configDir, configName)
+	assert.NoError(t, err)
+	assert.NotEqual(t, httpd.Conf{}, config.GetHTTPConfig())
+	assert.NotEqual(t, dataprovider.Config{}, config.GetProviderConf())
+	assert.NotEqual(t, sftpd.Configuration{}, config.GetSFTPDConfig())
+	assert.NotEqual(t, httpclient.Config{}, config.GetHTTPConfig())
 	confName := tempConfigName + ".json"
 	configFilePath := filepath.Join(configDir, confName)
 	err = config.LoadConfig(configDir, tempConfigName)
-	if err == nil {
-		t.Errorf("loading a non existent config file must fail")
-	}
-	ioutil.WriteFile(configFilePath, []byte("{invalid json}"), 0666)
+	assert.NotNil(t, err)
+	err = ioutil.WriteFile(configFilePath, []byte("{invalid json}"), os.ModePerm)
+	assert.NoError(t, err)
 	err = config.LoadConfig(configDir, tempConfigName)
-	if err == nil {
-		t.Errorf("loading an invalid config file must fail")
-	}
-	ioutil.WriteFile(configFilePath, []byte("{\"sftpd\": {\"bind_port\": \"a\"}}"), 0666)
+	assert.NotNil(t, err)
+	err = ioutil.WriteFile(configFilePath, []byte("{\"sftpd\": {\"bind_port\": \"a\"}}"), os.ModePerm)
+	assert.NoError(t, err)
 	err = config.LoadConfig(configDir, tempConfigName)
-	if err == nil {
-		t.Errorf("loading a config with an invalid bond_port must fail")
-	}
-	os.Remove(configFilePath)
+	assert.NotNil(t, err)
+	err = os.Remove(configFilePath)
+	assert.NoError(t, err)
 }
 
 func TestEmptyBanner(t *testing.T) {
 	configDir := ".."
 	confName := tempConfigName + ".json"
 	configFilePath := filepath.Join(configDir, confName)
-	config.LoadConfig(configDir, "")
+	err := config.LoadConfig(configDir, configName)
+	assert.NoError(t, err)
 	sftpdConf := config.GetSFTPDConfig()
 	sftpdConf.Banner = " "
 	c := make(map[string]sftpd.Configuration)
 	c["sftpd"] = sftpdConf
 	jsonConf, _ := json.Marshal(c)
-	err := ioutil.WriteFile(configFilePath, jsonConf, 0666)
-	if err != nil {
-		t.Errorf("error saving temporary configuration")
-	}
-	config.LoadConfig(configDir, tempConfigName)
+	err = ioutil.WriteFile(configFilePath, jsonConf, os.ModePerm)
+	assert.NoError(t, err)
+	err = config.LoadConfig(configDir, tempConfigName)
+	assert.NoError(t, err)
 	sftpdConf = config.GetSFTPDConfig()
-	if strings.TrimSpace(sftpdConf.Banner) == "" {
-		t.Errorf("SFTPD banner cannot be empty")
-	}
-	os.Remove(configFilePath)
+	assert.NotEmpty(t, strings.TrimSpace(sftpdConf.Banner))
+	err = os.Remove(configFilePath)
+	assert.NoError(t, err)
+
+	ftpdConf := config.GetFTPDConfig()
+	ftpdConf.Banner = " "
+	c1 := make(map[string]ftpd.Configuration)
+	c1["ftpd"] = ftpdConf
+	jsonConf, _ = json.Marshal(c1)
+	err = ioutil.WriteFile(configFilePath, jsonConf, os.ModePerm)
+	assert.NoError(t, err)
+	err = config.LoadConfig(configDir, tempConfigName)
+	assert.NoError(t, err)
+	ftpdConf = config.GetFTPDConfig()
+	assert.NotEmpty(t, strings.TrimSpace(ftpdConf.Banner))
+	err = os.Remove(configFilePath)
+	assert.NoError(t, err)
 }
 
 func TestInvalidUploadMode(t *testing.T) {
 	configDir := ".."
 	confName := tempConfigName + ".json"
 	configFilePath := filepath.Join(configDir, confName)
-	config.LoadConfig(configDir, "")
-	sftpdConf := config.GetSFTPDConfig()
-	sftpdConf.UploadMode = 10
-	c := make(map[string]sftpd.Configuration)
-	c["sftpd"] = sftpdConf
-	jsonConf, _ := json.Marshal(c)
-	err := ioutil.WriteFile(configFilePath, jsonConf, 0666)
-	if err != nil {
-		t.Errorf("error saving temporary configuration")
-	}
+	err := config.LoadConfig(configDir, configName)
+	assert.NoError(t, err)
+	commonConf := config.GetCommonConfig()
+	commonConf.UploadMode = 10
+	c := make(map[string]common.Configuration)
+	c["common"] = commonConf
+	jsonConf, err := json.Marshal(c)
+	assert.NoError(t, err)
+	err = ioutil.WriteFile(configFilePath, jsonConf, os.ModePerm)
+	assert.NoError(t, err)
 	err = config.LoadConfig(configDir, tempConfigName)
-	if err == nil {
-		t.Errorf("Loading configuration with invalid upload_mode must fail")
-	}
-	os.Remove(configFilePath)
+	assert.NotNil(t, err)
+	err = os.Remove(configFilePath)
+	assert.NoError(t, err)
 }
 
 func TestInvalidExternalAuthScope(t *testing.T) {
 	configDir := ".."
 	confName := tempConfigName + ".json"
 	configFilePath := filepath.Join(configDir, confName)
-	config.LoadConfig(configDir, "")
+	err := config.LoadConfig(configDir, configName)
+	assert.NoError(t, err)
 	providerConf := config.GetProviderConf()
 	providerConf.ExternalAuthScope = 10
 	c := make(map[string]dataprovider.Config)
 	c["data_provider"] = providerConf
-	jsonConf, _ := json.Marshal(c)
-	err := ioutil.WriteFile(configFilePath, jsonConf, 0666)
-	if err != nil {
-		t.Errorf("error saving temporary configuration")
-	}
+	jsonConf, err := json.Marshal(c)
+	assert.NoError(t, err)
+	err = ioutil.WriteFile(configFilePath, jsonConf, os.ModePerm)
+	assert.NoError(t, err)
 	err = config.LoadConfig(configDir, tempConfigName)
-	if err == nil {
-		t.Errorf("Loading configuration with invalid external_auth_scope must fail")
+	assert.NotNil(t, err)
+	err = os.Remove(configFilePath)
+	assert.NoError(t, err)
+}
+
+func TestInvalidCredentialsPath(t *testing.T) {
+	configDir := ".."
+	confName := tempConfigName + ".json"
+	configFilePath := filepath.Join(configDir, confName)
+	err := config.LoadConfig(configDir, configName)
+	assert.NoError(t, err)
+	providerConf := config.GetProviderConf()
+	providerConf.CredentialsPath = ""
+	c := make(map[string]dataprovider.Config)
+	c["data_provider"] = providerConf
+	jsonConf, err := json.Marshal(c)
+	assert.NoError(t, err)
+	err = ioutil.WriteFile(configFilePath, jsonConf, os.ModePerm)
+	assert.NoError(t, err)
+	err = config.LoadConfig(configDir, tempConfigName)
+	assert.NotNil(t, err)
+	err = os.Remove(configFilePath)
+	assert.NoError(t, err)
+}
+
+func TestInvalidProxyProtocol(t *testing.T) {
+	configDir := ".."
+	confName := tempConfigName + ".json"
+	configFilePath := filepath.Join(configDir, confName)
+	err := config.LoadConfig(configDir, configName)
+	assert.NoError(t, err)
+	commonConf := config.GetCommonConfig()
+	commonConf.ProxyProtocol = 10
+	c := make(map[string]common.Configuration)
+	c["common"] = commonConf
+	jsonConf, err := json.Marshal(c)
+	assert.NoError(t, err)
+	err = ioutil.WriteFile(configFilePath, jsonConf, os.ModePerm)
+	assert.NoError(t, err)
+	err = config.LoadConfig(configDir, tempConfigName)
+	assert.NotNil(t, err)
+	err = os.Remove(configFilePath)
+	assert.NoError(t, err)
+}
+
+func TestInvalidUsersBaseDir(t *testing.T) {
+	configDir := ".."
+	confName := tempConfigName + ".json"
+	configFilePath := filepath.Join(configDir, confName)
+	err := config.LoadConfig(configDir, configName)
+	assert.NoError(t, err)
+	providerConf := config.GetProviderConf()
+	providerConf.UsersBaseDir = "."
+	c := make(map[string]dataprovider.Config)
+	c["data_provider"] = providerConf
+	jsonConf, err := json.Marshal(c)
+	assert.NoError(t, err)
+	err = ioutil.WriteFile(configFilePath, jsonConf, os.ModePerm)
+	assert.NoError(t, err)
+	err = config.LoadConfig(configDir, tempConfigName)
+	assert.NotNil(t, err)
+	err = os.Remove(configFilePath)
+	assert.NoError(t, err)
+}
+
+func TestCommonParamsCompatibility(t *testing.T) {
+	configDir := ".."
+	confName := tempConfigName + ".json"
+	configFilePath := filepath.Join(configDir, confName)
+	err := config.LoadConfig(configDir, configName)
+	assert.NoError(t, err)
+	sftpdConf := config.GetSFTPDConfig()
+	sftpdConf.IdleTimeout = 21 //nolint:staticcheck
+	sftpdConf.Actions.Hook = "http://hook"
+	sftpdConf.Actions.ExecuteOn = []string{"upload"}
+	sftpdConf.SetstatMode = 1                                //nolint:staticcheck
+	sftpdConf.UploadMode = common.UploadModeAtomicWithResume //nolint:staticcheck
+	sftpdConf.ProxyProtocol = 1                              //nolint:staticcheck
+	sftpdConf.ProxyAllowed = []string{"192.168.1.1"}         //nolint:staticcheck
+	c := make(map[string]sftpd.Configuration)
+	c["sftpd"] = sftpdConf
+	jsonConf, err := json.Marshal(c)
+	assert.NoError(t, err)
+	err = ioutil.WriteFile(configFilePath, jsonConf, os.ModePerm)
+	assert.NoError(t, err)
+	err = config.LoadConfig(configDir, tempConfigName)
+	assert.NoError(t, err)
+	commonConf := config.GetCommonConfig()
+	assert.Equal(t, 21, commonConf.IdleTimeout)
+	assert.Equal(t, "http://hook", commonConf.Actions.Hook)
+	assert.Len(t, commonConf.Actions.ExecuteOn, 1)
+	assert.True(t, utils.IsStringInSlice("upload", commonConf.Actions.ExecuteOn))
+	assert.Equal(t, 1, commonConf.SetstatMode)
+	assert.Equal(t, 1, commonConf.ProxyProtocol)
+	assert.Len(t, commonConf.ProxyAllowed, 1)
+	assert.True(t, utils.IsStringInSlice("192.168.1.1", commonConf.ProxyAllowed))
+	err = os.Remove(configFilePath)
+	assert.NoError(t, err)
+}
+
+func TestHostKeyCompatibility(t *testing.T) {
+	configDir := ".."
+	confName := tempConfigName + ".json"
+	configFilePath := filepath.Join(configDir, confName)
+	err := config.LoadConfig(configDir, configName)
+	assert.NoError(t, err)
+	sftpdConf := config.GetSFTPDConfig()
+	sftpdConf.Keys = []sftpd.Key{ //nolint:staticcheck
+		{
+			PrivateKey: "rsa",
+		},
+		{
+			PrivateKey: "ecdsa",
+		},
 	}
-	os.Remove(configFilePath)
+	c := make(map[string]sftpd.Configuration)
+	c["sftpd"] = sftpdConf
+	jsonConf, err := json.Marshal(c)
+	assert.NoError(t, err)
+	err = ioutil.WriteFile(configFilePath, jsonConf, os.ModePerm)
+	assert.NoError(t, err)
+	err = config.LoadConfig(configDir, tempConfigName)
+	assert.NoError(t, err)
+	sftpdConf = config.GetSFTPDConfig()
+	assert.Equal(t, 2, len(sftpdConf.HostKeys))
+	assert.True(t, utils.IsStringInSlice("rsa", sftpdConf.HostKeys))
+	assert.True(t, utils.IsStringInSlice("ecdsa", sftpdConf.HostKeys))
+	err = os.Remove(configFilePath)
+	assert.NoError(t, err)
 }
 
 func TestSetGetConfig(t *testing.T) {
 	sftpdConf := config.GetSFTPDConfig()
-	sftpdConf.IdleTimeout = 3
+	sftpdConf.MaxAuthTries = 10
 	config.SetSFTPDConfig(sftpdConf)
-	if config.GetSFTPDConfig().IdleTimeout != sftpdConf.IdleTimeout {
-		t.Errorf("set sftpd conf failed")
-	}
+	assert.Equal(t, sftpdConf.MaxAuthTries, config.GetSFTPDConfig().MaxAuthTries)
 	dataProviderConf := config.GetProviderConf()
 	dataProviderConf.Host = "test host"
 	config.SetProviderConf(dataProviderConf)
-	if config.GetProviderConf().Host != dataProviderConf.Host {
-		t.Errorf("set data provider conf failed")
-	}
+	assert.Equal(t, dataProviderConf.Host, config.GetProviderConf().Host)
 	httpdConf := config.GetHTTPDConfig()
 	httpdConf.BindAddress = "0.0.0.0"
 	config.SetHTTPDConfig(httpdConf)
-	if config.GetHTTPDConfig().BindAddress != httpdConf.BindAddress {
-		t.Errorf("set httpd conf failed")
-	}
+	assert.Equal(t, httpdConf.BindAddress, config.GetHTTPDConfig().BindAddress)
+	commonConf := config.GetCommonConfig()
+	commonConf.IdleTimeout = 10
+	config.SetCommonConfig(commonConf)
+	assert.Equal(t, commonConf.IdleTimeout, config.GetCommonConfig().IdleTimeout)
+	ftpdConf := config.GetFTPDConfig()
+	ftpdConf.CertificateFile = "cert"
+	ftpdConf.CertificateKeyFile = "key"
+	config.SetFTPDConfig(ftpdConf)
+	assert.Equal(t, ftpdConf.CertificateFile, config.GetFTPDConfig().CertificateFile)
+	assert.Equal(t, ftpdConf.CertificateKeyFile, config.GetFTPDConfig().CertificateKeyFile)
+	webDavConf := config.GetWebDAVDConfig()
+	webDavConf.CertificateFile = "dav_cert"
+	webDavConf.CertificateKeyFile = "dav_key"
+	config.SetWebDAVDConfig(webDavConf)
+	assert.Equal(t, webDavConf.CertificateFile, config.GetWebDAVDConfig().CertificateFile)
+	assert.Equal(t, webDavConf.CertificateKeyFile, config.GetWebDAVDConfig().CertificateKeyFile)
 }

dataprovider/bolt.go

@@ -1,3 +1,5 @@
+// +build !nobolt
+
 package dataprovider
 
 import (
@@ -8,18 +10,22 @@ import (
 	"path/filepath"
 	"time"
 
+	bolt "go.etcd.io/bbolt"
+
 	"github.com/drakkan/sftpgo/logger"
 	"github.com/drakkan/sftpgo/utils"
-	bolt "go.etcd.io/bbolt"
+	"github.com/drakkan/sftpgo/version"
+	"github.com/drakkan/sftpgo/vfs"
 )
 
 const (
-	databaseVersion = 3
+	boltDatabaseVersion = 4
 )
 
 var (
 	usersBucket      = []byte("users")
 	usersIDIdxBucket = []byte("users_id_idx")
+	foldersBucket    = []byte("folders")
 	dbVersionBucket  = []byte("db_version")
 	dbVersionKey     = []byte("version")
 )
@@ -29,10 +35,6 @@ type BoltProvider struct {
 	dbHandle *bolt.DB
 }
 
-type boltDatabaseVersion struct {
-	Version int
-}
-
 type compatUserV2 struct {
 	ID                int64    `json:"id"`
 	Username          string   `json:"username"`
@@ -55,10 +57,17 @@ type compatUserV2 struct {
 	Status            int      `json:"status"`
 }
 
+func init() {
+	version.AddFeature("+bolt")
+}
+
 func initializeBoltProvider(basePath string) error {
 	var err error
-	logSender = BoltDataProviderName
+	logSender = fmt.Sprintf("dataprovider_%v", BoltDataProviderName)
 	dbPath := config.Name
+	if !utils.IsFileInputValid(dbPath) {
+		return fmt.Errorf("Invalid database path: %#v", dbPath)
+	}
 	if !filepath.IsAbs(dbPath) {
 		dbPath = filepath.Join(basePath, dbPath)
 	}
@@ -84,6 +93,14 @@ func initializeBoltProvider(basePath string) error {
 			providerLog(logger.LevelWarn, "error creating username idx bucket: %v", err)
 			return err
 		}
+		err = dbHandle.Update(func(tx *bolt.Tx) error {
+			_, e := tx.CreateBucketIfNotExists(foldersBucket)
+			return e
+		})
+		if err != nil {
+			providerLog(logger.LevelWarn, "error creating username idx bucket: %v", err)
+			return err
+		}
 		err = dbHandle.Update(func(tx *bolt.Tx) error {
 			_, e := tx.CreateBucketIfNotExists(dbVersionBucket)
 			return e
@@ -93,7 +110,6 @@ func initializeBoltProvider(basePath string) error {
 			return err
 		}
 		provider = BoltProvider{dbHandle: dbHandle}
-		err = checkBoltDatabaseVersion(dbHandle)
 	} else {
 		providerLog(logger.LevelWarn, "error creating bolt key/value store handler: %v", err)
 	}
@@ -101,11 +117,11 @@ func initializeBoltProvider(basePath string) error {
 }
 
 func (p BoltProvider) checkAvailability() error {
-	_, err := p.getUsers(1, 0, "ASC", "")
+	_, err := getBoltDatabaseVersion(p.dbHandle)
 	return err
 }
 
-func (p BoltProvider) validateUserAndPass(username string, password string) (User, error) {
+func (p BoltProvider) validateUserAndPass(username, password, ip, protocol string) (User, error) {
 	var user User
 	if len(password) == 0 {
 		return user, errors.New("Credentials cannot be null or empty")
@@ -115,10 +131,10 @@ func (p BoltProvider) validateUserAndPass(username string, password string) (Use
 		providerLog(logger.LevelWarn, "error authenticating user: %v, error: %v", username, err)
 		return user, err
 	}
-	return checkUserAndPass(user, password)
+	return checkUserAndPass(user, password, ip, protocol)
 }
 
-func (p BoltProvider) validateUserAndPubKey(username string, pubKey string) (User, string, error) {
+func (p BoltProvider) validateUserAndPubKey(username string, pubKey []byte) (User, string, error) {
 	var user User
 	if len(pubKey) == 0 {
 		return user, "", errors.New("Credentials cannot be null or empty")
@@ -147,7 +163,12 @@ func (p BoltProvider) getUserByID(ID int64) (User, error) {
 		if u == nil {
 			return &RecordNotFoundError{err: fmt.Sprintf("username %#v and ID: %v does not exist", string(username), ID)}
 		}
-		return json.Unmarshal(u, &user)
+		folderBucket, err := getFolderBucket(tx)
+		if err != nil {
+			return err
+		}
+		user, err = joinUserAndFolders(u, folderBucket)
+		return err
 	})
 
 	return user, err
@@ -173,7 +194,13 @@ func (p BoltProvider) updateLastLogin(username string) error {
 		if err != nil {
 			return err
 		}
-		return bucket.Put([]byte(username), buf)
+		err = bucket.Put([]byte(username), buf)
+		if err == nil {
+			providerLog(logger.LevelDebug, "last login updated for user %#v", username)
+		} else {
+			providerLog(logger.LevelWarn, "error updating last login for user %#v: %v", username, err)
+		}
+		return err
 	})
 }
 
@@ -204,7 +231,10 @@ func (p BoltProvider) updateQuota(username string, filesAdd int, sizeAdd int64,
 		if err != nil {
 			return err
 		}
-		return bucket.Put([]byte(username), buf)
+		err = bucket.Put([]byte(username), buf)
+		providerLog(logger.LevelDebug, "quota updated for user %#v, files increment: %v size increment: %v is reset? %v",
+			username, filesAdd, sizeAdd, reset)
+		return err
 	})
 }
 
@@ -228,7 +258,12 @@ func (p BoltProvider) userExists(username string) (User, error) {
 		if u == nil {
 			return &RecordNotFoundError{err: fmt.Sprintf("username %v does not exist", username)}
 		}
-		return json.Unmarshal(u, &user)
+		folderBucket, err := getFolderBucket(tx)
+		if err != nil {
+			return err
+		}
+		user, err = joinUserAndFolders(u, folderBucket)
+		return err
 	})
 	return user, err
 }
@@ -243,6 +278,10 @@ func (p BoltProvider) addUser(user User) error {
 		if err != nil {
 			return err
 		}
+		folderBucket, err := getFolderBucket(tx)
+		if err != nil {
+			return err
+		}
 		if u := bucket.Get([]byte(user.Username)); u != nil {
 			return fmt.Errorf("username %v already exists", user.Username)
 		}
@@ -251,15 +290,25 @@ func (p BoltProvider) addUser(user User) error {
 			return err
 		}
 		user.ID = int64(id)
+		user.LastQuotaUpdate = 0
+		user.UsedQuotaSize = 0
+		user.UsedQuotaFiles = 0
+		user.LastLogin = 0
+		for _, folder := range user.VirtualFolders {
+			err = addUserToFolderMapping(folder, user, folderBucket)
+			if err != nil {
+				return err
+			}
+		}
 		buf, err := json.Marshal(user)
 		if err != nil {
 			return err
 		}
-		userIDAsBytes := itob(user.ID)
 		err = bucket.Put([]byte(user.Username), buf)
 		if err != nil {
 			return err
 		}
+		userIDAsBytes := itob(user.ID)
 		return idxBucket.Put(userIDAsBytes, []byte(user.Username))
 	})
 }
@@ -274,9 +323,35 @@ func (p BoltProvider) updateUser(user User) error {
 		if err != nil {
 			return err
 		}
-		if u := bucket.Get([]byte(user.Username)); u == nil {
+		folderBucket, err := getFolderBucket(tx)
+		if err != nil {
+			return err
+		}
+		var u []byte
+		if u = bucket.Get([]byte(user.Username)); u == nil {
 			return &RecordNotFoundError{err: fmt.Sprintf("username %v does not exist", user.Username)}
 		}
+		var oldUser User
+		err = json.Unmarshal(u, &oldUser)
+		if err != nil {
+			return err
+		}
+		for _, folder := range oldUser.VirtualFolders {
+			err = removeUserFromFolderMapping(folder, oldUser, folderBucket)
+			if err != nil {
+				return err
+			}
+		}
+		for _, folder := range user.VirtualFolders {
+			err = addUserToFolderMapping(folder, user, folderBucket)
+			if err != nil {
+				return err
+			}
+		}
+		user.LastQuotaUpdate = oldUser.LastQuotaUpdate
+		user.UsedQuotaSize = oldUser.UsedQuotaSize
+		user.UsedQuotaFiles = oldUser.UsedQuotaFiles
+		user.LastLogin = oldUser.LastLogin
 		buf, err := json.Marshal(user)
 		if err != nil {
 			return err
@@ -291,6 +366,18 @@ func (p BoltProvider) deleteUser(user User) error {
 		if err != nil {
 			return err
 		}
+		if len(user.VirtualFolders) > 0 {
+			folderBucket, err := getFolderBucket(tx)
+			if err != nil {
+				return err
+			}
+			for _, folder := range user.VirtualFolders {
+				err = removeUserFromFolderMapping(folder, user, folderBucket)
+				if err != nil {
+					return err
+				}
+			}
+		}
 		userIDAsBytes := itob(user.ID)
 		userName := idxBucket.Get(userIDAsBytes)
 		if userName == nil {
@@ -305,17 +392,23 @@ func (p BoltProvider) deleteUser(user User) error {
 }
 
 func (p BoltProvider) dumpUsers() ([]User, error) {
-	users := []User{}
-	var err error
-	err = p.dbHandle.View(func(tx *bolt.Tx) error {
+	users := make([]User, 0, 100)
+	err := p.dbHandle.View(func(tx *bolt.Tx) error {
 		bucket, _, err := getBuckets(tx)
 		if err != nil {
 			return err
 		}
+		folderBucket, err := getFolderBucket(tx)
+		if err != nil {
+			return err
+		}
 		cursor := bucket.Cursor()
 		for k, v := cursor.First(); k != nil; k, v = cursor.Next() {
-			var user User
-			err = json.Unmarshal(v, &user)
+			user, err := joinUserAndFolders(v, folderBucket)
+			if err != nil {
+				return err
+			}
+			err = addCredentialsToUser(&user)
 			if err != nil {
 				return err
 			}
@@ -326,18 +419,29 @@ func (p BoltProvider) dumpUsers() ([]User, error) {
 	return users, err
 }
 
-func (p BoltProvider) getUsers(limit int, offset int, order string, username string) ([]User, error) {
+func (p BoltProvider) getUserWithUsername(username string) ([]User, error) {
 	users := []User{}
+	var user User
+	user, err := p.userExists(username)
+	if err == nil {
+		users = append(users, HideUserSensitiveData(&user))
+		return users, nil
+	}
+	if _, ok := err.(*RecordNotFoundError); ok {
+		err = nil
+	}
+	return users, err
+}
+
+func (p BoltProvider) getUsers(limit int, offset int, order string, username string) ([]User, error) {
+	users := make([]User, 0, limit)
 	var err error
 	if limit <= 0 {
 		return users, err
 	}
 	if len(username) > 0 {
 		if offset == 0 {
-			user, err := p.userExists(username)
-			if err == nil {
-				users = append(users, getUserNoCredentials(&user))
-			}
+			return p.getUserWithUsername(username)
 		}
 		return users, err
 	}
@@ -346,18 +450,21 @@ func (p BoltProvider) getUsers(limit int, offset int, order string, username str
 		if err != nil {
 			return err
 		}
+		folderBucket, err := getFolderBucket(tx)
+		if err != nil {
+			return err
+		}
 		cursor := bucket.Cursor()
 		itNum := 0
-		if order == "ASC" {
+		if order == OrderASC {
 			for k, v := cursor.First(); k != nil; k, v = cursor.Next() {
 				itNum++
 				if itNum <= offset {
 					continue
 				}
-				var user User
-				err = json.Unmarshal(v, &user)
+				user, err := joinUserAndFolders(v, folderBucket)
 				if err == nil {
-					users = append(users, getUserNoCredentials(&user))
+					users = append(users, HideUserSensitiveData(&user))
 				}
 				if len(users) >= limit {
 					break
@@ -369,10 +476,9 @@ func (p BoltProvider) getUsers(limit int, offset int, order string, username str
 				if itNum <= offset {
 					continue
 				}
-				var user User
-				err = json.Unmarshal(v, &user)
+				user, err := joinUserAndFolders(v, folderBucket)
 				if err == nil {
-					users = append(users, getUserNoCredentials(&user))
+					users = append(users, HideUserSensitiveData(&user))
 				}
 				if len(users) >= limit {
 					break
@@ -384,13 +490,253 @@ func (p BoltProvider) getUsers(limit int, offset int, order string, username str
 	return users, err
 }
 
+func (p BoltProvider) dumpFolders() ([]vfs.BaseVirtualFolder, error) {
+	folders := make([]vfs.BaseVirtualFolder, 0, 50)
+	err := p.dbHandle.View(func(tx *bolt.Tx) error {
+		bucket, err := getFolderBucket(tx)
+		if err != nil {
+			return err
+		}
+		cursor := bucket.Cursor()
+		for k, v := cursor.First(); k != nil; k, v = cursor.Next() {
+			var folder vfs.BaseVirtualFolder
+			err = json.Unmarshal(v, &folder)
+			if err != nil {
+				return err
+			}
+			folders = append(folders, folder)
+		}
+		return err
+	})
+	return folders, err
+}
+
+func (p BoltProvider) getFolders(limit, offset int, order, folderPath string) ([]vfs.BaseVirtualFolder, error) {
+	folders := make([]vfs.BaseVirtualFolder, 0, limit)
+	var err error
+	if limit <= 0 {
+		return folders, err
+	}
+	if len(folderPath) > 0 {
+		if offset == 0 {
+			var folder vfs.BaseVirtualFolder
+			folder, err = p.getFolderByPath(folderPath)
+			if err == nil {
+				folders = append(folders, folder)
+			}
+		}
+		return folders, err
+	}
+	err = p.dbHandle.View(func(tx *bolt.Tx) error {
+		bucket, err := getFolderBucket(tx)
+		if err != nil {
+			return err
+		}
+		cursor := bucket.Cursor()
+		itNum := 0
+		if order == OrderASC {
+			for k, v := cursor.First(); k != nil; k, v = cursor.Next() {
+				itNum++
+				if itNum <= offset {
+					continue
+				}
+				var folder vfs.BaseVirtualFolder
+				err = json.Unmarshal(v, &folder)
+				if err != nil {
+					return err
+				}
+				folders = append(folders, folder)
+				if len(folders) >= limit {
+					break
+				}
+			}
+		} else {
+			for k, v := cursor.Last(); k != nil; k, v = cursor.Prev() {
+				itNum++
+				if itNum <= offset {
+					continue
+				}
+				var folder vfs.BaseVirtualFolder
+				err = json.Unmarshal(v, &folder)
+				if err != nil {
+					return err
+				}
+				folders = append(folders, folder)
+				if len(folders) >= limit {
+					break
+				}
+			}
+		}
+		return err
+	})
+	return folders, err
+}
+
+func (p BoltProvider) getFolderByPath(name string) (vfs.BaseVirtualFolder, error) {
+	var folder vfs.BaseVirtualFolder
+	err := p.dbHandle.View(func(tx *bolt.Tx) error {
+		bucket, err := getFolderBucket(tx)
+		if err != nil {
+			return err
+		}
+		folder, err = folderExistsInternal(name, bucket)
+		return err
+	})
+	return folder, err
+}
+
+func (p BoltProvider) addFolder(folder vfs.BaseVirtualFolder) error {
+	err := validateFolder(&folder)
+	if err != nil {
+		return err
+	}
+	return p.dbHandle.Update(func(tx *bolt.Tx) error {
+		bucket, err := getFolderBucket(tx)
+		if err != nil {
+			return err
+		}
+		if f := bucket.Get([]byte(folder.MappedPath)); f != nil {
+			return fmt.Errorf("folder %v already exists", folder.MappedPath)
+		}
+		_, err = addFolderInternal(folder, bucket)
+		return err
+	})
+}
+
+func (p BoltProvider) deleteFolder(folder vfs.BaseVirtualFolder) error {
+	return p.dbHandle.Update(func(tx *bolt.Tx) error {
+		bucket, err := getFolderBucket(tx)
+		if err != nil {
+			return err
+		}
+		usersBucket, _, err := getBuckets(tx)
+		if err != nil {
+			return err
+		}
+		var f []byte
+		if f = bucket.Get([]byte(folder.MappedPath)); f == nil {
+			return &RecordNotFoundError{err: fmt.Sprintf("folder %v does not exist", folder.MappedPath)}
+		}
+		var folder vfs.BaseVirtualFolder
+		err = json.Unmarshal(f, &folder)
+		if err != nil {
+			return err
+		}
+		for _, username := range folder.Users {
+			var u []byte
+			if u = usersBucket.Get([]byte(username)); u == nil {
+				continue
+			}
+			var user User
+			err = json.Unmarshal(u, &user)
+			if err != nil {
+				return err
+			}
+			var folders []vfs.VirtualFolder
+			for _, userFolder := range user.VirtualFolders {
+				if folder.MappedPath != userFolder.MappedPath {
+					folders = append(folders, userFolder)
+				}
+			}
+			user.VirtualFolders = folders
+			buf, err := json.Marshal(user)
+			if err != nil {
+				return err
+			}
+			err = usersBucket.Put([]byte(user.Username), buf)
+			if err != nil {
+				return err
+			}
+		}
+
+		return bucket.Delete([]byte(folder.MappedPath))
+	})
+}
+
+func (p BoltProvider) updateFolderQuota(mappedPath string, filesAdd int, sizeAdd int64, reset bool) error {
+	return p.dbHandle.Update(func(tx *bolt.Tx) error {
+		bucket, err := getFolderBucket(tx)
+		if err != nil {
+			return err
+		}
+		var f []byte
+		if f = bucket.Get([]byte(mappedPath)); f == nil {
+			return &RecordNotFoundError{err: fmt.Sprintf("folder %v does not exist, unable to update quota", mappedPath)}
+		}
+		var folder vfs.BaseVirtualFolder
+		err = json.Unmarshal(f, &folder)
+		if err != nil {
+			return err
+		}
+		if reset {
+			folder.UsedQuotaSize = sizeAdd
+			folder.UsedQuotaFiles = filesAdd
+		} else {
+			folder.UsedQuotaSize += sizeAdd
+			folder.UsedQuotaFiles += filesAdd
+		}
+		folder.LastQuotaUpdate = utils.GetTimeAsMsSinceEpoch(time.Now())
+		buf, err := json.Marshal(folder)
+		if err != nil {
+			return err
+		}
+		return bucket.Put([]byte(folder.MappedPath), buf)
+	})
+}
+
+func (p BoltProvider) getUsedFolderQuota(mappedPath string) (int, int64, error) {
+	folder, err := p.getFolderByPath(mappedPath)
+	if err != nil {
+		providerLog(logger.LevelWarn, "unable to get quota for folder %#v error: %v", mappedPath, err)
+		return 0, 0, err
+	}
+	return folder.UsedQuotaFiles, folder.UsedQuotaSize, err
+}
+
 func (p BoltProvider) close() error {
 	return p.dbHandle.Close()
 }
 
-func getUserNoCredentials(user *User) User {
-	user.Password = ""
-	return *user
+func (p BoltProvider) reloadConfig() error {
+	return nil
+}
+
+// initializeDatabase does nothing, no initilization is needed for bolt provider
+func (p BoltProvider) initializeDatabase() error {
+	return ErrNoInitRequired
+}
+
+func (p BoltProvider) migrateDatabase() error {
+	dbVersion, err := getBoltDatabaseVersion(p.dbHandle)
+	if err != nil {
+		return err
+	}
+	if dbVersion.Version == boltDatabaseVersion {
+		providerLog(logger.LevelDebug, "bolt database is up to date, current version: %v", dbVersion.Version)
+		return ErrNoInitRequired
+	}
+	switch dbVersion.Version {
+	case 1:
+		err = updateDatabaseFrom1To2(p.dbHandle)
+		if err != nil {
+			return err
+		}
+		err = updateDatabaseFrom2To3(p.dbHandle)
+		if err != nil {
+			return err
+		}
+		return updateDatabaseFrom3To4(p.dbHandle)
+	case 2:
+		err = updateDatabaseFrom2To3(p.dbHandle)
+		if err != nil {
+			return err
+		}
+		return updateDatabaseFrom3To4(p.dbHandle)
+	case 3:
+		return updateDatabaseFrom3To4(p.dbHandle)
+	default:
+		return fmt.Errorf("Database version not handled: %v", dbVersion.Version)
+	}
 }
 
 // itob returns an 8-byte big endian representation of v.
@@ -400,6 +746,106 @@ func itob(v int64) []byte {
 	return b
 }
 
+func joinUserAndFolders(u []byte, foldersBucket *bolt.Bucket) (User, error) {
+	var user User
+	err := json.Unmarshal(u, &user)
+	if len(user.VirtualFolders) > 0 {
+		var folders []vfs.VirtualFolder
+		for _, folder := range user.VirtualFolders {
+			baseFolder, err := folderExistsInternal(folder.MappedPath, foldersBucket)
+			if err != nil {
+				continue
+			}
+			folder.UsedQuotaFiles = baseFolder.UsedQuotaFiles
+			folder.UsedQuotaSize = baseFolder.UsedQuotaSize
+			folder.LastQuotaUpdate = baseFolder.LastQuotaUpdate
+			folder.ID = baseFolder.ID
+			folders = append(folders, folder)
+		}
+		user.VirtualFolders = folders
+	}
+	return user, err
+}
+
+func folderExistsInternal(name string, bucket *bolt.Bucket) (vfs.BaseVirtualFolder, error) {
+	var folder vfs.BaseVirtualFolder
+	f := bucket.Get([]byte(name))
+	if f == nil {
+		err := &RecordNotFoundError{err: fmt.Sprintf("folder %v does not exist", name)}
+		return folder, err
+	}
+	err := json.Unmarshal(f, &folder)
+	return folder, err
+}
+
+func addFolderInternal(folder vfs.BaseVirtualFolder, bucket *bolt.Bucket) (vfs.BaseVirtualFolder, error) {
+	id, err := bucket.NextSequence()
+	if err != nil {
+		return folder, err
+	}
+	folder.ID = int64(id)
+	buf, err := json.Marshal(folder)
+	if err != nil {
+		return folder, err
+	}
+	err = bucket.Put([]byte(folder.MappedPath), buf)
+	return folder, err
+}
+
+func addUserToFolderMapping(folder vfs.VirtualFolder, user User, bucket *bolt.Bucket) error {
+	var baseFolder vfs.BaseVirtualFolder
+	var err error
+	if f := bucket.Get([]byte(folder.MappedPath)); f == nil {
+		// folder does not exists, try to create
+		baseFolder, err = addFolderInternal(folder.BaseVirtualFolder, bucket)
+	} else {
+		err = json.Unmarshal(f, &baseFolder)
+	}
+	if err != nil {
+		return err
+	}
+	if !utils.IsStringInSlice(user.Username, baseFolder.Users) {
+		baseFolder.Users = append(baseFolder.Users, user.Username)
+		buf, err := json.Marshal(baseFolder)
+		if err != nil {
+			return err
+		}
+		err = bucket.Put([]byte(folder.MappedPath), buf)
+		if err != nil {
+			return err
+		}
+	}
+	return err
+}
+
+func removeUserFromFolderMapping(folder vfs.VirtualFolder, user User, bucket *bolt.Bucket) error {
+	var f []byte
+	if f = bucket.Get([]byte(folder.MappedPath)); f == nil {
+		// the folder does not exists so there is no associated user
+		return nil
+	}
+	var baseFolder vfs.BaseVirtualFolder
+	err := json.Unmarshal(f, &baseFolder)
+	if err != nil {
+		return err
+	}
+	if utils.IsStringInSlice(user.Username, baseFolder.Users) {
+		var newUserMapping []string
+		for _, u := range baseFolder.Users {
+			if u != user.Username {
+				newUserMapping = append(newUserMapping, u)
+			}
+		}
+		baseFolder.Users = newUserMapping
+		buf, err := json.Marshal(baseFolder)
+		if err != nil {
+			return err
+		}
+		return bucket.Put([]byte(folder.MappedPath), buf)
+	}
+	return err
+}
+
 func getBuckets(tx *bolt.Tx) (*bolt.Bucket, *bolt.Bucket, error) {
 	var err error
 	bucket := tx.Bucket(usersBucket)
@@ -410,29 +856,17 @@ func getBuckets(tx *bolt.Tx) (*bolt.Bucket, *bolt.Bucket, error) {
 	return bucket, idxBucket, err
 }
 
-func checkBoltDatabaseVersion(dbHandle *bolt.DB) error {
-	dbVersion, err := getBoltDatabaseVersion(dbHandle)
-	if err != nil {
-		return err
+func getFolderBucket(tx *bolt.Tx) (*bolt.Bucket, error) {
+	var err error
+	bucket := tx.Bucket(foldersBucket)
+	if bucket == nil {
+		err = fmt.Errorf("unable to find required buckets, bolt database structure not correcly defined")
 	}
-	if dbVersion.Version == databaseVersion {
-		providerLog(logger.LevelDebug, "bolt database updated, version: %v", dbVersion.Version)
-		return nil
-	}
-	if dbVersion.Version == 1 {
-		err = updateDatabaseFrom1To2(dbHandle)
-		if err != nil {
-			return err
-		}
-		return updateDatabaseFrom2To3(dbHandle)
-	} else if dbVersion.Version == 2 {
-		return updateDatabaseFrom2To3(dbHandle)
-	}
-
-	return nil
+	return bucket, err
 }
 
 func updateDatabaseFrom1To2(dbHandle *bolt.DB) error {
+	logger.InfoToConsole("updating bolt database version: 1 -> 2")
 	providerLog(logger.LevelInfo, "updating bolt database version: 1 -> 2")
 	usernames, err := getBoltAvailableUsernames(dbHandle)
 	if err != nil {
@@ -454,6 +888,7 @@ func updateDatabaseFrom1To2(dbHandle *bolt.DB) error {
 }
 
 func updateDatabaseFrom2To3(dbHandle *bolt.DB) error {
+	logger.InfoToConsole("updating bolt database version: 2 -> 3")
 	providerLog(logger.LevelInfo, "updating bolt database version: 2 -> 3")
 	users := []User{}
 	err := dbHandle.View(func(tx *bolt.Tx) error {
@@ -507,6 +942,70 @@ func updateDatabaseFrom2To3(dbHandle *bolt.DB) error {
 	return updateBoltDatabaseVersion(dbHandle, 3)
 }
 
+func updateDatabaseFrom3To4(dbHandle *bolt.DB) error {
+	logger.InfoToConsole("updating bolt database version: 3 -> 4")
+	providerLog(logger.LevelInfo, "updating bolt database version: 3 -> 4")
+	foldersToScan := []string{}
+	users := []userCompactVFolders{}
+	err := dbHandle.View(func(tx *bolt.Tx) error {
+		bucket, _, err := getBuckets(tx)
+		if err != nil {
+			return err
+		}
+		cursor := bucket.Cursor()
+		for k, v := cursor.First(); k != nil; k, v = cursor.Next() {
+			var compatUser userCompactVFolders
+			err = json.Unmarshal(v, &compatUser)
+			if err == nil && len(compatUser.VirtualFolders) > 0 {
+				users = append(users, compatUser)
+			}
+		}
+		return err
+	})
+	if err != nil {
+		return err
+	}
+	for _, u := range users {
+		user, err := provider.userExists(u.Username)
+		if err != nil {
+			return err
+		}
+		var folders []vfs.VirtualFolder
+		for _, f := range u.VirtualFolders {
+			providerLog(logger.LevelInfo, "restoring virtual folder: %+v for user %#v", f, user.Username)
+			quotaSize := int64(-1)
+			quotaFiles := -1
+			if f.ExcludeFromQuota {
+				quotaSize = 0
+				quotaFiles = 0
+			}
+			folder := vfs.VirtualFolder{
+				QuotaSize:   quotaSize,
+				QuotaFiles:  quotaFiles,
+				VirtualPath: f.VirtualPath,
+			}
+			folder.MappedPath = f.MappedPath
+			folders = append(folders, folder)
+			if !utils.IsStringInSlice(folder.MappedPath, foldersToScan) {
+				foldersToScan = append(foldersToScan, folder.MappedPath)
+			}
+		}
+		user.VirtualFolders = folders
+		err = provider.updateUser(user)
+		providerLog(logger.LevelInfo, "number of virtual folders to restore %v, user %#v, error: %v", len(user.VirtualFolders),
+			user.Username, err)
+		if err != nil {
+			return err
+		}
+	}
+
+	err = updateBoltDatabaseVersion(dbHandle, 4)
+	if err == nil {
+		go updateVFoldersQuotaAfterRestore(foldersToScan)
+	}
+	return err
+}
+
 func getBoltAvailableUsernames(dbHandle *bolt.DB) ([]string, error) {
 	usernames := []string{}
 	err := dbHandle.View(func(tx *bolt.Tx) error {
@@ -524,8 +1023,8 @@ func getBoltAvailableUsernames(dbHandle *bolt.DB) ([]string, error) {
 	return usernames, err
 }
 
-func getBoltDatabaseVersion(dbHandle *bolt.DB) (boltDatabaseVersion, error) {
-	var dbVersion boltDatabaseVersion
+func getBoltDatabaseVersion(dbHandle *bolt.DB) (schemaVersion, error) {
+	var dbVersion schemaVersion
 	err := dbHandle.View(func(tx *bolt.Tx) error {
 		bucket := tx.Bucket(dbVersionBucket)
 		if bucket == nil {
@@ -533,7 +1032,7 @@ func getBoltDatabaseVersion(dbHandle *bolt.DB) (boltDatabaseVersion, error) {
 		}
 		v := bucket.Get(dbVersionKey)
 		if v == nil {
-			dbVersion = boltDatabaseVersion{
+			dbVersion = schemaVersion{
 				Version: 1,
 			}
 			return nil
@@ -549,7 +1048,7 @@ func updateBoltDatabaseVersion(dbHandle *bolt.DB, version int) error {
 		if bucket == nil {
 			return fmt.Errorf("unable to find database version bucket")
 		}
-		newDbVersion := boltDatabaseVersion{
+		newDbVersion := schemaVersion{
 			Version: version,
 		}
 		buf, err := json.Marshal(newDbVersion)

dataprovider/bolt_disabled.go

@@ -0,0 +1,17 @@
+// +build nobolt
+
+package dataprovider
+
+import (
+	"errors"
+
+	"github.com/drakkan/sftpgo/version"
+)
+
+func init() {
+	version.AddFeature("-bolt")
+}
+
+func initializeBoltProvider(basePath string) error {
+	return errors.New("bolt disabled at build time")
+}

dataprovider/memory.go

@@ -1,14 +1,19 @@
 package dataprovider
 
 import (
+	"encoding/json"
 	"errors"
 	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
 	"sort"
 	"sync"
 	"time"
 
 	"github.com/drakkan/sftpgo/logger"
 	"github.com/drakkan/sftpgo/utils"
+	"github.com/drakkan/sftpgo/vfs"
 )
 
 var (
@@ -16,6 +21,9 @@ var (
 )
 
 type memoryProviderHandle struct {
+	// configuration file to use for loading users
+	configFile string
+	sync.Mutex
 	isClosed bool
 	// slice with ordered usernames
 	usernames []string
@@ -23,7 +31,10 @@ type memoryProviderHandle struct {
 	usersIdx map[int64]string
 	// map for users, username is the key
 	users map[string]User
-	lock  *sync.Mutex
+	// map for virtual folders, MappedPath is the key
+	vfolders map[string]vfs.BaseVirtualFolder
+	// slice with ordered folders mapped path
+	vfoldersPaths []string
 }
 
 // MemoryProvider auth provider for a memory store
@@ -31,22 +42,32 @@ type MemoryProvider struct {
 	dbHandle *memoryProviderHandle
 }
 
-func initializeMemoryProvider() error {
+func initializeMemoryProvider(basePath string) error {
+	logSender = fmt.Sprintf("dataprovider_%v", MemoryDataProviderName)
+	configFile := ""
+	if utils.IsFileInputValid(config.Name) {
+		configFile = config.Name
+		if !filepath.IsAbs(configFile) {
+			configFile = filepath.Join(basePath, configFile)
+		}
+	}
 	provider = MemoryProvider{
 		dbHandle: &memoryProviderHandle{
-			isClosed:  false,
-			usernames: []string{},
-			usersIdx:  make(map[int64]string),
-			users:     make(map[string]User),
-			lock:      new(sync.Mutex),
+			isClosed:      false,
+			usernames:     []string{},
+			usersIdx:      make(map[int64]string),
+			users:         make(map[string]User),
+			vfolders:      make(map[string]vfs.BaseVirtualFolder),
+			vfoldersPaths: []string{},
+			configFile:    configFile,
 		},
 	}
-	return nil
+	return provider.reloadConfig()
 }
 
 func (p MemoryProvider) checkAvailability() error {
-	p.dbHandle.lock.Lock()
-	defer p.dbHandle.lock.Unlock()
+	p.dbHandle.Lock()
+	defer p.dbHandle.Unlock()
 	if p.dbHandle.isClosed {
 		return errMemoryProviderClosed
 	}
@@ -54,8 +75,8 @@ func (p MemoryProvider) checkAvailability() error {
 }
 
 func (p MemoryProvider) close() error {
-	p.dbHandle.lock.Lock()
-	defer p.dbHandle.lock.Unlock()
+	p.dbHandle.Lock()
+	defer p.dbHandle.Unlock()
 	if p.dbHandle.isClosed {
 		return errMemoryProviderClosed
 	}
@@ -63,35 +84,35 @@ func (p MemoryProvider) close() error {
 	return nil
 }
 
-func (p MemoryProvider) validateUserAndPass(username string, password string) (User, error) {
+func (p MemoryProvider) validateUserAndPass(username, password, ip, protocol string) (User, error) {
 	var user User
 	if len(password) == 0 {
 		return user, errors.New("Credentials cannot be null or empty")
 	}
 	user, err := p.userExists(username)
 	if err != nil {
-		providerLog(logger.LevelWarn, "error authenticating user: %v, error: %v", username, err)
+		providerLog(logger.LevelWarn, "error authenticating user %#v, error: %v", username, err)
 		return user, err
 	}
-	return checkUserAndPass(user, password)
+	return checkUserAndPass(user, password, ip, protocol)
 }
 
-func (p MemoryProvider) validateUserAndPubKey(username string, pubKey string) (User, string, error) {
+func (p MemoryProvider) validateUserAndPubKey(username string, pubKey []byte) (User, string, error) {
 	var user User
 	if len(pubKey) == 0 {
 		return user, "", errors.New("Credentials cannot be null or empty")
 	}
 	user, err := p.userExists(username)
 	if err != nil {
-		providerLog(logger.LevelWarn, "error authenticating user: %v, error: %v", username, err)
+		providerLog(logger.LevelWarn, "error authenticating user %#v, error: %v", username, err)
 		return user, "", err
 	}
 	return checkUserAndPubKey(user, pubKey)
 }
 
 func (p MemoryProvider) getUserByID(ID int64) (User, error) {
-	p.dbHandle.lock.Lock()
-	defer p.dbHandle.lock.Unlock()
+	p.dbHandle.Lock()
+	defer p.dbHandle.Unlock()
 	if p.dbHandle.isClosed {
 		return User{}, errMemoryProviderClosed
 	}
@@ -102,8 +123,8 @@ func (p MemoryProvider) getUserByID(ID int64) (User, error) {
 }
 
 func (p MemoryProvider) updateLastLogin(username string) error {
-	p.dbHandle.lock.Lock()
-	defer p.dbHandle.lock.Unlock()
+	p.dbHandle.Lock()
+	defer p.dbHandle.Unlock()
 	if p.dbHandle.isClosed {
 		return errMemoryProviderClosed
 	}
@@ -117,14 +138,14 @@ func (p MemoryProvider) updateLastLogin(username string) error {
 }
 
 func (p MemoryProvider) updateQuota(username string, filesAdd int, sizeAdd int64, reset bool) error {
-	p.dbHandle.lock.Lock()
-	defer p.dbHandle.lock.Unlock()
+	p.dbHandle.Lock()
+	defer p.dbHandle.Unlock()
 	if p.dbHandle.isClosed {
 		return errMemoryProviderClosed
 	}
 	user, err := p.userExistsInternal(username)
 	if err != nil {
-		providerLog(logger.LevelWarn, "unable to update quota for user %v error: %v", username, err)
+		providerLog(logger.LevelWarn, "unable to update quota for user %#v error: %v", username, err)
 		return err
 	}
 	if reset {
@@ -135,27 +156,29 @@ func (p MemoryProvider) updateQuota(username string, filesAdd int, sizeAdd int64
 		user.UsedQuotaFiles += filesAdd
 	}
 	user.LastQuotaUpdate = utils.GetTimeAsMsSinceEpoch(time.Now())
+	providerLog(logger.LevelDebug, "quota updated for user %#v, files increment: %v size increment: %v is reset? %v",
+		username, filesAdd, sizeAdd, reset)
 	p.dbHandle.users[user.Username] = user
 	return nil
 }
 
 func (p MemoryProvider) getUsedQuota(username string) (int, int64, error) {
-	p.dbHandle.lock.Lock()
-	defer p.dbHandle.lock.Unlock()
+	p.dbHandle.Lock()
+	defer p.dbHandle.Unlock()
 	if p.dbHandle.isClosed {
 		return 0, 0, errMemoryProviderClosed
 	}
 	user, err := p.userExistsInternal(username)
 	if err != nil {
-		providerLog(logger.LevelWarn, "unable to get quota for user %v error: %v", username, err)
+		providerLog(logger.LevelWarn, "unable to get quota for user %#v error: %v", username, err)
 		return 0, 0, err
 	}
 	return user.UsedQuotaFiles, user.UsedQuotaSize, err
 }
 
 func (p MemoryProvider) addUser(user User) error {
-	p.dbHandle.lock.Lock()
-	defer p.dbHandle.lock.Unlock()
+	p.dbHandle.Lock()
+	defer p.dbHandle.Unlock()
 	if p.dbHandle.isClosed {
 		return errMemoryProviderClosed
 	}
@@ -165,9 +188,14 @@ func (p MemoryProvider) addUser(user User) error {
 	}
 	_, err = p.userExistsInternal(user.Username)
 	if err == nil {
-		return fmt.Errorf("username %v already exists", user.Username)
+		return fmt.Errorf("username %#v already exists", user.Username)
 	}
 	user.ID = p.getNextID()
+	user.LastQuotaUpdate = 0
+	user.UsedQuotaSize = 0
+	user.UsedQuotaFiles = 0
+	user.LastLogin = 0
+	user.VirtualFolders = p.joinVirtualFoldersFields(user)
 	p.dbHandle.users[user.Username] = user
 	p.dbHandle.usersIdx[user.ID] = user.Username
 	p.dbHandle.usernames = append(p.dbHandle.usernames, user.Username)
@@ -176,8 +204,8 @@ func (p MemoryProvider) addUser(user User) error {
 }
 
 func (p MemoryProvider) updateUser(user User) error {
-	p.dbHandle.lock.Lock()
-	defer p.dbHandle.lock.Unlock()
+	p.dbHandle.Lock()
+	defer p.dbHandle.Unlock()
 	if p.dbHandle.isClosed {
 		return errMemoryProviderClosed
 	}
@@ -185,24 +213,35 @@ func (p MemoryProvider) updateUser(user User) error {
 	if err != nil {
 		return err
 	}
-	_, err = p.userExistsInternal(user.Username)
+	u, err := p.userExistsInternal(user.Username)
 	if err != nil {
 		return err
 	}
+	for _, oldFolder := range u.VirtualFolders {
+		p.removeUserFromFolderMapping(oldFolder.MappedPath, u.Username)
+	}
+	user.VirtualFolders = p.joinVirtualFoldersFields(user)
+	user.LastQuotaUpdate = u.LastQuotaUpdate
+	user.UsedQuotaSize = u.UsedQuotaSize
+	user.UsedQuotaFiles = u.UsedQuotaFiles
+	user.LastLogin = u.LastLogin
 	p.dbHandle.users[user.Username] = user
 	return nil
 }
 
 func (p MemoryProvider) deleteUser(user User) error {
-	p.dbHandle.lock.Lock()
-	defer p.dbHandle.lock.Unlock()
+	p.dbHandle.Lock()
+	defer p.dbHandle.Unlock()
 	if p.dbHandle.isClosed {
 		return errMemoryProviderClosed
 	}
-	_, err := p.userExistsInternal(user.Username)
+	u, err := p.userExistsInternal(user.Username)
 	if err != nil {
 		return err
 	}
+	for _, oldFolder := range u.VirtualFolders {
+		p.removeUserFromFolderMapping(oldFolder.MappedPath, u.Username)
+	}
 	delete(p.dbHandle.users, user.Username)
 	delete(p.dbHandle.usersIdx, user.ID)
 	// this could be more efficient
@@ -215,25 +254,42 @@ func (p MemoryProvider) deleteUser(user User) error {
 }
 
 func (p MemoryProvider) dumpUsers() ([]User, error) {
-	users := []User{}
+	p.dbHandle.Lock()
+	defer p.dbHandle.Unlock()
+	users := make([]User, 0, len(p.dbHandle.usernames))
 	var err error
-	p.dbHandle.lock.Lock()
-	defer p.dbHandle.lock.Unlock()
 	if p.dbHandle.isClosed {
 		return users, errMemoryProviderClosed
 	}
 	for _, username := range p.dbHandle.usernames {
 		user := p.dbHandle.users[username]
+		err = addCredentialsToUser(&user)
+		if err != nil {
+			return users, err
+		}
 		users = append(users, user)
 	}
 	return users, err
 }
 
+func (p MemoryProvider) dumpFolders() ([]vfs.BaseVirtualFolder, error) {
+	p.dbHandle.Lock()
+	defer p.dbHandle.Unlock()
+	folders := make([]vfs.BaseVirtualFolder, 0, len(p.dbHandle.vfoldersPaths))
+	if p.dbHandle.isClosed {
+		return folders, errMemoryProviderClosed
+	}
+	for _, f := range p.dbHandle.vfolders {
+		folders = append(folders, f)
+	}
+	return folders, nil
+}
+
 func (p MemoryProvider) getUsers(limit int, offset int, order string, username string) ([]User, error) {
-	users := []User{}
+	users := make([]User, 0, limit)
 	var err error
-	p.dbHandle.lock.Lock()
-	defer p.dbHandle.lock.Unlock()
+	p.dbHandle.Lock()
+	defer p.dbHandle.Unlock()
 	if p.dbHandle.isClosed {
 		return users, errMemoryProviderClosed
 	}
@@ -244,22 +300,20 @@ func (p MemoryProvider) getUsers(limit int, offset int, order string, username s
 		if offset == 0 {
 			user, err := p.userExistsInternal(username)
 			if err == nil {
-				user.Password = ""
-				users = append(users, user)
+				users = append(users, HideUserSensitiveData(&user))
 			}
 		}
 		return users, err
 	}
 	itNum := 0
-	if order == "ASC" {
+	if order == OrderASC {
 		for _, username := range p.dbHandle.usernames {
 			itNum++
 			if itNum <= offset {
 				continue
 			}
 			user := p.dbHandle.users[username]
-			user.Password = ""
-			users = append(users, user)
+			users = append(users, HideUserSensitiveData(&user))
 			if len(users) >= limit {
 				break
 			}
@@ -272,8 +326,7 @@ func (p MemoryProvider) getUsers(limit int, offset int, order string, username s
 			}
 			username := p.dbHandle.usernames[i]
 			user := p.dbHandle.users[username]
-			user.Password = ""
-			users = append(users, user)
+			users = append(users, HideUserSensitiveData(&user))
 			if len(users) >= limit {
 				break
 			}
@@ -283,8 +336,8 @@ func (p MemoryProvider) getUsers(limit int, offset int, order string, username s
 }
 
 func (p MemoryProvider) userExists(username string) (User, error) {
-	p.dbHandle.lock.Lock()
-	defer p.dbHandle.lock.Unlock()
+	p.dbHandle.Lock()
+	defer p.dbHandle.Unlock()
 	if p.dbHandle.isClosed {
 		return User{}, errMemoryProviderClosed
 	}
@@ -295,7 +348,224 @@ func (p MemoryProvider) userExistsInternal(username string) (User, error) {
 	if val, ok := p.dbHandle.users[username]; ok {
 		return val.getACopy(), nil
 	}
-	return User{}, &RecordNotFoundError{err: fmt.Sprintf("username %v does not exist", username)}
+	return User{}, &RecordNotFoundError{err: fmt.Sprintf("username %#v does not exist", username)}
+}
+
+func (p MemoryProvider) updateFolderQuota(mappedPath string, filesAdd int, sizeAdd int64, reset bool) error {
+	p.dbHandle.Lock()
+	defer p.dbHandle.Unlock()
+	if p.dbHandle.isClosed {
+		return errMemoryProviderClosed
+	}
+	folder, err := p.folderExistsInternal(mappedPath)
+	if err != nil {
+		providerLog(logger.LevelWarn, "unable to update quota for folder %#v error: %v", mappedPath, err)
+		return err
+	}
+	if reset {
+		folder.UsedQuotaSize = sizeAdd
+		folder.UsedQuotaFiles = filesAdd
+	} else {
+		folder.UsedQuotaSize += sizeAdd
+		folder.UsedQuotaFiles += filesAdd
+	}
+	folder.LastQuotaUpdate = utils.GetTimeAsMsSinceEpoch(time.Now())
+	p.dbHandle.vfolders[mappedPath] = folder
+	return nil
+}
+
+func (p MemoryProvider) getUsedFolderQuota(mappedPath string) (int, int64, error) {
+	p.dbHandle.Lock()
+	defer p.dbHandle.Unlock()
+	if p.dbHandle.isClosed {
+		return 0, 0, errMemoryProviderClosed
+	}
+	folder, err := p.folderExistsInternal(mappedPath)
+	if err != nil {
+		providerLog(logger.LevelWarn, "unable to get quota for folder %#v error: %v", mappedPath, err)
+		return 0, 0, err
+	}
+	return folder.UsedQuotaFiles, folder.UsedQuotaSize, err
+}
+
+func (p MemoryProvider) joinVirtualFoldersFields(user User) []vfs.VirtualFolder {
+	var folders []vfs.VirtualFolder
+	for _, folder := range user.VirtualFolders {
+		f, err := p.addOrGetFolderInternal(folder.MappedPath, user.Username, folder.UsedQuotaSize, folder.UsedQuotaFiles,
+			folder.LastQuotaUpdate)
+		if err == nil {
+			folder.UsedQuotaFiles = f.UsedQuotaFiles
+			folder.UsedQuotaSize = f.UsedQuotaSize
+			folder.LastQuotaUpdate = f.LastQuotaUpdate
+			folder.ID = f.ID
+			folders = append(folders, folder)
+		}
+	}
+	return folders
+}
+
+func (p MemoryProvider) removeUserFromFolderMapping(mappedPath, username string) {
+	folder, err := p.folderExistsInternal(mappedPath)
+	if err == nil {
+		var usernames []string
+		for _, user := range folder.Users {
+			if user != username {
+				usernames = append(usernames, user)
+			}
+		}
+		folder.Users = usernames
+		p.dbHandle.vfolders[folder.MappedPath] = folder
+	}
+}
+
+func (p MemoryProvider) updateFoldersMappingInternal(folder vfs.BaseVirtualFolder) {
+	p.dbHandle.vfolders[folder.MappedPath] = folder
+	if !utils.IsStringInSlice(folder.MappedPath, p.dbHandle.vfoldersPaths) {
+		p.dbHandle.vfoldersPaths = append(p.dbHandle.vfoldersPaths, folder.MappedPath)
+		sort.Strings(p.dbHandle.vfoldersPaths)
+	}
+}
+
+func (p MemoryProvider) addOrGetFolderInternal(mappedPath, username string, usedQuotaSize int64, usedQuotaFiles int, lastQuotaUpdate int64) (vfs.BaseVirtualFolder, error) {
+	folder, err := p.folderExistsInternal(mappedPath)
+	if _, ok := err.(*RecordNotFoundError); ok {
+		folder := vfs.BaseVirtualFolder{
+			ID:              p.getNextFolderID(),
+			MappedPath:      mappedPath,
+			UsedQuotaSize:   usedQuotaSize,
+			UsedQuotaFiles:  usedQuotaFiles,
+			LastQuotaUpdate: lastQuotaUpdate,
+			Users:           []string{username},
+		}
+		p.updateFoldersMappingInternal(folder)
+		return folder, nil
+	}
+	if err == nil && !utils.IsStringInSlice(username, folder.Users) {
+		folder.Users = append(folder.Users, username)
+		p.updateFoldersMappingInternal(folder)
+	}
+	return folder, err
+}
+
+func (p MemoryProvider) folderExistsInternal(mappedPath string) (vfs.BaseVirtualFolder, error) {
+	if val, ok := p.dbHandle.vfolders[mappedPath]; ok {
+		return val, nil
+	}
+	return vfs.BaseVirtualFolder{}, &RecordNotFoundError{err: fmt.Sprintf("folder %#v does not exist", mappedPath)}
+}
+
+func (p MemoryProvider) getFolders(limit, offset int, order, folderPath string) ([]vfs.BaseVirtualFolder, error) {
+	folders := make([]vfs.BaseVirtualFolder, 0, limit)
+	var err error
+	p.dbHandle.Lock()
+	defer p.dbHandle.Unlock()
+	if p.dbHandle.isClosed {
+		return folders, errMemoryProviderClosed
+	}
+	if limit <= 0 {
+		return folders, err
+	}
+	if len(folderPath) > 0 {
+		if offset == 0 {
+			var folder vfs.BaseVirtualFolder
+			folder, err = p.folderExistsInternal(folderPath)
+			if err == nil {
+				folders = append(folders, folder)
+			}
+		}
+		return folders, err
+	}
+	itNum := 0
+	if order == OrderASC {
+		for _, mappedPath := range p.dbHandle.vfoldersPaths {
+			itNum++
+			if itNum <= offset {
+				continue
+			}
+			folder := p.dbHandle.vfolders[mappedPath]
+			folders = append(folders, folder)
+			if len(folders) >= limit {
+				break
+			}
+		}
+	} else {
+		for i := len(p.dbHandle.vfoldersPaths) - 1; i >= 0; i-- {
+			itNum++
+			if itNum <= offset {
+				continue
+			}
+			mappedPath := p.dbHandle.vfoldersPaths[i]
+			folder := p.dbHandle.vfolders[mappedPath]
+			folders = append(folders, folder)
+			if len(folders) >= limit {
+				break
+			}
+		}
+	}
+	return folders, err
+}
+
+func (p MemoryProvider) getFolderByPath(mappedPath string) (vfs.BaseVirtualFolder, error) {
+	p.dbHandle.Lock()
+	defer p.dbHandle.Unlock()
+	if p.dbHandle.isClosed {
+		return vfs.BaseVirtualFolder{}, errMemoryProviderClosed
+	}
+	return p.folderExistsInternal(mappedPath)
+}
+
+func (p MemoryProvider) addFolder(folder vfs.BaseVirtualFolder) error {
+	p.dbHandle.Lock()
+	defer p.dbHandle.Unlock()
+	if p.dbHandle.isClosed {
+		return errMemoryProviderClosed
+	}
+	err := validateFolder(&folder)
+	if err != nil {
+		return err
+	}
+	_, err = p.folderExistsInternal(folder.MappedPath)
+	if err == nil {
+		return fmt.Errorf("folder %#v already exists", folder.MappedPath)
+	}
+	folder.ID = p.getNextFolderID()
+	p.dbHandle.vfolders[folder.MappedPath] = folder
+	p.dbHandle.vfoldersPaths = append(p.dbHandle.vfoldersPaths, folder.MappedPath)
+	sort.Strings(p.dbHandle.vfoldersPaths)
+	return nil
+}
+
+func (p MemoryProvider) deleteFolder(folder vfs.BaseVirtualFolder) error {
+	p.dbHandle.Lock()
+	defer p.dbHandle.Unlock()
+	if p.dbHandle.isClosed {
+		return errMemoryProviderClosed
+	}
+
+	_, err := p.folderExistsInternal(folder.MappedPath)
+	if err != nil {
+		return err
+	}
+	for _, username := range folder.Users {
+		user, err := p.userExistsInternal(username)
+		if err == nil {
+			var folders []vfs.VirtualFolder
+			for _, userFolder := range user.VirtualFolders {
+				if folder.MappedPath != userFolder.MappedPath {
+					folders = append(folders, userFolder)
+				}
+			}
+			user.VirtualFolders = folders
+			p.dbHandle.users[user.Username] = user
+		}
+	}
+	delete(p.dbHandle.vfolders, folder.MappedPath)
+	p.dbHandle.vfoldersPaths = []string{}
+	for mappedPath := range p.dbHandle.vfolders {
+		p.dbHandle.vfoldersPaths = append(p.dbHandle.vfoldersPaths, mappedPath)
+	}
+	sort.Strings(p.dbHandle.vfoldersPaths)
+	return nil
 }
 
 func (p MemoryProvider) getNextID() int64 {
@@ -307,3 +577,99 @@ func (p MemoryProvider) getNextID() int64 {
 	}
 	return nextID
 }
+
+func (p MemoryProvider) getNextFolderID() int64 {
+	nextID := int64(1)
+	for _, v := range p.dbHandle.vfolders {
+		if v.ID >= nextID {
+			nextID = v.ID + 1
+		}
+	}
+	return nextID
+}
+
+func (p MemoryProvider) clear() {
+	p.dbHandle.Lock()
+	defer p.dbHandle.Unlock()
+	p.dbHandle.usernames = []string{}
+	p.dbHandle.usersIdx = make(map[int64]string)
+	p.dbHandle.users = make(map[string]User)
+	p.dbHandle.vfoldersPaths = []string{}
+	p.dbHandle.vfolders = make(map[string]vfs.BaseVirtualFolder)
+}
+
+func (p MemoryProvider) reloadConfig() error {
+	if len(p.dbHandle.configFile) == 0 {
+		providerLog(logger.LevelDebug, "no users configuration file defined")
+		return nil
+	}
+	providerLog(logger.LevelDebug, "loading users from file: %#v", p.dbHandle.configFile)
+	fi, err := os.Stat(p.dbHandle.configFile)
+	if err != nil {
+		providerLog(logger.LevelWarn, "error loading users: %v", err)
+		return err
+	}
+	if fi.Size() == 0 {
+		err = errors.New("users configuration file is invalid, its size must be > 0")
+		providerLog(logger.LevelWarn, "error loading users: %v", err)
+		return err
+	}
+	if fi.Size() > 10485760 {
+		err = errors.New("users configuration file is invalid, its size must be <= 10485760 bytes")
+		providerLog(logger.LevelWarn, "error loading users: %v", err)
+		return err
+	}
+	content, err := ioutil.ReadFile(p.dbHandle.configFile)
+	if err != nil {
+		providerLog(logger.LevelWarn, "error loading users: %v", err)
+		return err
+	}
+	var dump BackupData
+	err = json.Unmarshal(content, &dump)
+	if err != nil {
+		providerLog(logger.LevelWarn, "error loading users: %v", err)
+		return err
+	}
+	p.clear()
+	for _, folder := range dump.Folders {
+		_, err := p.getFolderByPath(folder.MappedPath)
+		if err == nil {
+			logger.Debug(logSender, "", "folder %#v already exists, restore not needed", folder.MappedPath)
+			continue
+		}
+		folder.Users = nil
+		err = p.addFolder(folder)
+		if err != nil {
+			providerLog(logger.LevelWarn, "error adding folder %#v: %v", folder.MappedPath, err)
+			return err
+		}
+	}
+	for _, user := range dump.Users {
+		u, err := p.userExists(user.Username)
+		if err == nil {
+			user.ID = u.ID
+			err = p.updateUser(user)
+			if err != nil {
+				providerLog(logger.LevelWarn, "error updating user %#v: %v", user.Username, err)
+				return err
+			}
+		} else {
+			err = p.addUser(user)
+			if err != nil {
+				providerLog(logger.LevelWarn, "error adding user %#v: %v", user.Username, err)
+				return err
+			}
+		}
+	}
+	providerLog(logger.LevelDebug, "user and folders loaded from file: %#v", p.dbHandle.configFile)
+	return nil
+}
+
+// initializeDatabase does nothing, no initilization is needed for memory provider
+func (p MemoryProvider) initializeDatabase() error {
+	return ErrNoInitRequired
+}
+
+func (p MemoryProvider) migrateDatabase() error {
+	return ErrNoInitRequired
+}

dataprovider/mysql.go

@@ -1,11 +1,43 @@
+// +build !nomysql
+
 package dataprovider
 
 import (
+	"context"
 	"database/sql"
 	"fmt"
+	"strings"
 	"time"
 
+	// we import go-sql-driver/mysql here to be able to disable MySQL support using a build tag
+	_ "github.com/go-sql-driver/mysql"
+
 	"github.com/drakkan/sftpgo/logger"
+	"github.com/drakkan/sftpgo/version"
+	"github.com/drakkan/sftpgo/vfs"
+)
+
+const (
+	mysqlUsersTableSQL = "CREATE TABLE `{{users}}` (`id` integer AUTO_INCREMENT NOT NULL PRIMARY KEY, " +
+		"`username` varchar(255) NOT NULL UNIQUE, `password` varchar(255) NULL, `public_keys` longtext NULL, " +
+		"`home_dir` varchar(255) NOT NULL, `uid` integer NOT NULL, `gid` integer NOT NULL, `max_sessions` integer NOT NULL, " +
+		" `quota_size` bigint NOT NULL, `quota_files` integer NOT NULL, `permissions` longtext NOT NULL, " +
+		"`used_quota_size` bigint NOT NULL, `used_quota_files` integer NOT NULL, `last_quota_update` bigint NOT NULL, " +
+		"`upload_bandwidth` integer NOT NULL, `download_bandwidth` integer NOT NULL, `expiration_date` bigint(20) NOT NULL, " +
+		"`last_login` bigint(20) NOT NULL, `status` int(11) NOT NULL, `filters` longtext DEFAULT NULL, " +
+		"`filesystem` longtext DEFAULT NULL);"
+	mysqlSchemaTableSQL = "CREATE TABLE `{{schema_version}}` (`id` integer AUTO_INCREMENT NOT NULL PRIMARY KEY, `version` integer NOT NULL);"
+	mysqlV2SQL          = "ALTER TABLE `{{users}}` ADD COLUMN `virtual_folders` longtext NULL;"
+	mysqlV3SQL          = "ALTER TABLE `{{users}}` MODIFY `password` longtext NULL;"
+	mysqlV4SQL          = "CREATE TABLE `{{folders}}` (`id` integer AUTO_INCREMENT NOT NULL PRIMARY KEY, `path` varchar(512) NOT NULL UNIQUE," +
+		"`used_quota_size` bigint NOT NULL, `used_quota_files` integer NOT NULL, `last_quota_update` bigint NOT NULL);" +
+		"ALTER TABLE `{{users}}` MODIFY `home_dir` varchar(512) NOT NULL;" +
+		"ALTER TABLE `{{users}}` DROP COLUMN `virtual_folders`;" +
+		"CREATE TABLE `{{folders_mapping}}` (`id` integer AUTO_INCREMENT NOT NULL PRIMARY KEY, `virtual_path` varchar(512) NOT NULL, " +
+		"`quota_size` bigint NOT NULL, `quota_files` integer NOT NULL, `folder_id` integer NOT NULL, `user_id` integer NOT NULL);" +
+		"ALTER TABLE `{{folders_mapping}}` ADD CONSTRAINT `unique_mapping` UNIQUE (`user_id`, `folder_id`);" +
+		"ALTER TABLE `{{folders_mapping}}` ADD CONSTRAINT `folders_mapping_folder_id_fk_folders_id` FOREIGN KEY (`folder_id`) REFERENCES `{{folders}}` (`id`) ON DELETE CASCADE;" +
+		"ALTER TABLE `{{folders_mapping}}` ADD CONSTRAINT `folders_mapping_user_id_fk_users_id` FOREIGN KEY (`user_id`) REFERENCES `{{users}}` (`id`) ON DELETE CASCADE;"
 )
 
 // MySQLProvider auth provider for MySQL/MariaDB database
@@ -13,9 +45,13 @@ type MySQLProvider struct {
 	dbHandle *sql.DB
 }
 
+func init() {
+	version.AddFeature("+mysql")
+}
+
 func initializeMySQLProvider() error {
 	var err error
-	logSender = MySQLDataProviderName
+	logSender = fmt.Sprintf("dataprovider_%v", MySQLDataProviderName)
 	dbHandle, err := sql.Open("mysql", getMySQLConnectionString(false))
 	if err == nil {
 		providerLog(logger.LevelDebug, "mysql database handle created, connection string: %#v, pool size: %v",
@@ -48,11 +84,11 @@ func (p MySQLProvider) checkAvailability() error {
 	return sqlCommonCheckAvailability(p.dbHandle)
 }
 
-func (p MySQLProvider) validateUserAndPass(username string, password string) (User, error) {
-	return sqlCommonValidateUserAndPass(username, password, p.dbHandle)
+func (p MySQLProvider) validateUserAndPass(username, password, ip, protocol string) (User, error) {
+	return sqlCommonValidateUserAndPass(username, password, ip, protocol, p.dbHandle)
 }
 
-func (p MySQLProvider) validateUserAndPubKey(username string, publicKey string) (User, string, error) {
+func (p MySQLProvider) validateUserAndPubKey(username string, publicKey []byte) (User, string, error) {
 	return sqlCommonValidateUserAndPubKey(username, publicKey, p.dbHandle)
 }
 
@@ -64,14 +100,14 @@ func (p MySQLProvider) updateQuota(username string, filesAdd int, sizeAdd int64,
 	return sqlCommonUpdateQuota(username, filesAdd, sizeAdd, reset, p.dbHandle)
 }
 
-func (p MySQLProvider) updateLastLogin(username string) error {
-	return sqlCommonUpdateLastLogin(username, p.dbHandle)
-}
-
 func (p MySQLProvider) getUsedQuota(username string) (int, int64, error) {
 	return sqlCommonGetUsedQuota(username, p.dbHandle)
 }
 
+func (p MySQLProvider) updateLastLogin(username string) error {
+	return sqlCommonUpdateLastLogin(username, p.dbHandle)
+}
+
 func (p MySQLProvider) userExists(username string) (User, error) {
 	return sqlCommonCheckUserExists(username, p.dbHandle)
 }
@@ -96,6 +132,120 @@ func (p MySQLProvider) getUsers(limit int, offset int, order string, username st
 	return sqlCommonGetUsers(limit, offset, order, username, p.dbHandle)
 }
 
+func (p MySQLProvider) dumpFolders() ([]vfs.BaseVirtualFolder, error) {
+	return sqlCommonDumpFolders(p.dbHandle)
+}
+
+func (p MySQLProvider) getFolders(limit, offset int, order, folderPath string) ([]vfs.BaseVirtualFolder, error) {
+	return sqlCommonGetFolders(limit, offset, order, folderPath, p.dbHandle)
+}
+
+func (p MySQLProvider) getFolderByPath(mappedPath string) (vfs.BaseVirtualFolder, error) {
+	ctx, cancel := context.WithTimeout(context.Background(), defaultSQLQueryTimeout)
+	defer cancel()
+	return sqlCommonCheckFolderExists(ctx, mappedPath, p.dbHandle)
+}
+
+func (p MySQLProvider) addFolder(folder vfs.BaseVirtualFolder) error {
+	return sqlCommonAddFolder(folder, p.dbHandle)
+}
+
+func (p MySQLProvider) deleteFolder(folder vfs.BaseVirtualFolder) error {
+	return sqlCommonDeleteFolder(folder, p.dbHandle)
+}
+
+func (p MySQLProvider) updateFolderQuota(mappedPath string, filesAdd int, sizeAdd int64, reset bool) error {
+	return sqlCommonUpdateFolderQuota(mappedPath, filesAdd, sizeAdd, reset, p.dbHandle)
+}
+
+func (p MySQLProvider) getUsedFolderQuota(mappedPath string) (int, int64, error) {
+	return sqlCommonGetFolderUsedQuota(mappedPath, p.dbHandle)
+}
+
 func (p MySQLProvider) close() error {
 	return p.dbHandle.Close()
 }
+
+func (p MySQLProvider) reloadConfig() error {
+	return nil
+}
+
+// initializeDatabase creates the initial database structure
+func (p MySQLProvider) initializeDatabase() error {
+	dbVersion, err := sqlCommonGetDatabaseVersion(p.dbHandle, false)
+	if err == nil && dbVersion.Version > 0 {
+		return ErrNoInitRequired
+	}
+	sqlUsers := strings.Replace(mysqlUsersTableSQL, "{{users}}", sqlTableUsers, 1)
+	tx, err := p.dbHandle.Begin()
+	if err != nil {
+		return err
+	}
+	_, err = tx.Exec(sqlUsers)
+	if err != nil {
+		sqlCommonRollbackTransaction(tx)
+		return err
+	}
+	_, err = tx.Exec(strings.Replace(mysqlSchemaTableSQL, "{{schema_version}}", sqlTableSchemaVersion, 1))
+	if err != nil {
+		sqlCommonRollbackTransaction(tx)
+		return err
+	}
+	_, err = tx.Exec(strings.Replace(initialDBVersionSQL, "{{schema_version}}", sqlTableSchemaVersion, 1))
+	if err != nil {
+		sqlCommonRollbackTransaction(tx)
+		return err
+	}
+	return tx.Commit()
+}
+
+func (p MySQLProvider) migrateDatabase() error {
+	dbVersion, err := sqlCommonGetDatabaseVersion(p.dbHandle, true)
+	if err != nil {
+		return err
+	}
+	if dbVersion.Version == sqlDatabaseVersion {
+		providerLog(logger.LevelDebug, "sql database is up to date, current version: %v", dbVersion.Version)
+		return ErrNoInitRequired
+	}
+	switch dbVersion.Version {
+	case 1:
+		err = updateMySQLDatabaseFrom1To2(p.dbHandle)
+		if err != nil {
+			return err
+		}
+		err = updateMySQLDatabaseFrom2To3(p.dbHandle)
+		if err != nil {
+			return err
+		}
+		return updateMySQLDatabaseFrom3To4(p.dbHandle)
+	case 2:
+		err = updateMySQLDatabaseFrom2To3(p.dbHandle)
+		if err != nil {
+			return err
+		}
+		return updateMySQLDatabaseFrom3To4(p.dbHandle)
+	case 3:
+		return updateMySQLDatabaseFrom3To4(p.dbHandle)
+	default:
+		return fmt.Errorf("Database version not handled: %v", dbVersion.Version)
+	}
+}
+
+func updateMySQLDatabaseFrom1To2(dbHandle *sql.DB) error {
+	logger.InfoToConsole("updating database version: 1 -> 2")
+	providerLog(logger.LevelInfo, "updating database version: 1 -> 2")
+	sql := strings.Replace(mysqlV2SQL, "{{users}}", sqlTableUsers, 1)
+	return sqlCommonExecSQLAndUpdateDBVersion(dbHandle, []string{sql}, 2)
+}
+
+func updateMySQLDatabaseFrom2To3(dbHandle *sql.DB) error {
+	logger.InfoToConsole("updating database version: 2 -> 3")
+	providerLog(logger.LevelInfo, "updating database version: 2 -> 3")
+	sql := strings.Replace(mysqlV3SQL, "{{users}}", sqlTableUsers, 1)
+	return sqlCommonExecSQLAndUpdateDBVersion(dbHandle, []string{sql}, 3)
+}
+
+func updateMySQLDatabaseFrom3To4(dbHandle *sql.DB) error {
+	return sqlCommonUpdateDatabaseFrom3To4(mysqlV4SQL, dbHandle)
+}

dataprovider/mysql_disabled.go

@@ -0,0 +1,17 @@
+// +build nomysql
+
+package dataprovider
+
+import (
+	"errors"
+
+	"github.com/drakkan/sftpgo/version"
+)
+
+func init() {
+	version.AddFeature("-mysql")
+}
+
+func initializeMySQLProvider() error {
+	return errors.New("MySQL disabled at build time")
+}

dataprovider/pgsql.go

@@ -1,10 +1,42 @@
+// +build !nopgsql
+
 package dataprovider
 
 import (
+	"context"
 	"database/sql"
 	"fmt"
+	"strings"
+
+	// we import lib/pq here to be able to disable PostgreSQL support using a build tag
+	_ "github.com/lib/pq"
 
 	"github.com/drakkan/sftpgo/logger"
+	"github.com/drakkan/sftpgo/version"
+	"github.com/drakkan/sftpgo/vfs"
+)
+
+const (
+	pgsqlUsersTableSQL = `CREATE TABLE "{{users}}" ("id" serial NOT NULL PRIMARY KEY, "username" varchar(255) NOT NULL UNIQUE,
+"password" varchar(255) NULL, "public_keys" text NULL, "home_dir" varchar(255) NOT NULL, "uid" integer NOT NULL,
+"gid" integer NOT NULL, "max_sessions" integer NOT NULL, "quota_size" bigint NOT NULL, "quota_files" integer NOT NULL,
+"permissions" text NOT NULL, "used_quota_size" bigint NOT NULL, "used_quota_files" integer NOT NULL,
+"last_quota_update" bigint NOT NULL, "upload_bandwidth" integer NOT NULL, "download_bandwidth" integer NOT NULL,
+"expiration_date" bigint NOT NULL, "last_login" bigint NOT NULL, "status" integer NOT NULL, "filters" text NULL,
+"filesystem" text NULL);`
+	pgsqlSchemaTableSQL = `CREATE TABLE "{{schema_version}}" ("id" serial NOT NULL PRIMARY KEY, "version" integer NOT NULL);`
+	pgsqlV2SQL          = `ALTER TABLE "{{users}}" ADD COLUMN "virtual_folders" text NULL;`
+	pgsqlV3SQL          = `ALTER TABLE "{{users}}" ALTER COLUMN "password" TYPE text USING "password"::text;`
+	pgsqlV4SQL          = `CREATE TABLE "{{folders}}" ("id" serial NOT NULL PRIMARY KEY, "path" varchar(512) NOT NULL UNIQUE, "used_quota_size" bigint NOT NULL, "used_quota_files" integer NOT NULL, "last_quota_update" bigint NOT NULL);
+ALTER TABLE "{{users}}" ALTER COLUMN "home_dir" TYPE varchar(512) USING "home_dir"::varchar(512);
+ALTER TABLE "{{users}}" DROP COLUMN "virtual_folders" CASCADE;
+CREATE TABLE "{{folders_mapping}}" ("id" serial NOT NULL PRIMARY KEY, "virtual_path" varchar(512) NOT NULL, "quota_size" bigint NOT NULL, "quota_files" integer NOT NULL, "folder_id" integer NOT NULL, "user_id" integer NOT NULL);
+ALTER TABLE "{{folders_mapping}}" ADD CONSTRAINT "unique_mapping" UNIQUE ("user_id", "folder_id");
+ALTER TABLE "{{folders_mapping}}" ADD CONSTRAINT "folders_mapping_folder_id_fk_folders_id" FOREIGN KEY ("folder_id") REFERENCES "{{folders}}" ("id") MATCH SIMPLE ON UPDATE NO ACTION ON DELETE CASCADE DEFERRABLE INITIALLY DEFERRED;
+ALTER TABLE "{{folders_mapping}}" ADD CONSTRAINT "folders_mapping_user_id_fk_users_id" FOREIGN KEY ("user_id") REFERENCES "{{users}}" ("id") MATCH SIMPLE ON UPDATE NO ACTION ON DELETE CASCADE DEFERRABLE INITIALLY DEFERRED;
+CREATE INDEX "folders_mapping_folder_id_idx" ON "{{folders_mapping}}" ("folder_id");
+CREATE INDEX "folders_mapping_user_id_idx" ON "{{folders_mapping}}" ("user_id");
+`
 )
 
 // PGSQLProvider auth provider for PostgreSQL database
@@ -12,9 +44,13 @@ type PGSQLProvider struct {
 	dbHandle *sql.DB
 }
 
+func init() {
+	version.AddFeature("+pgsql")
+}
+
 func initializePGSQLProvider() error {
 	var err error
-	logSender = PGSQLDataProviderName
+	logSender = fmt.Sprintf("dataprovider_%v", PGSQLDataProviderName)
 	dbHandle, err := sql.Open("postgres", getPGSQLConnectionString(false))
 	if err == nil {
 		providerLog(logger.LevelDebug, "postgres database handle created, connection string: %#v, pool size: %v",
@@ -47,11 +83,11 @@ func (p PGSQLProvider) checkAvailability() error {
 	return sqlCommonCheckAvailability(p.dbHandle)
 }
 
-func (p PGSQLProvider) validateUserAndPass(username string, password string) (User, error) {
-	return sqlCommonValidateUserAndPass(username, password, p.dbHandle)
+func (p PGSQLProvider) validateUserAndPass(username, password, ip, protocol string) (User, error) {
+	return sqlCommonValidateUserAndPass(username, password, ip, protocol, p.dbHandle)
 }
 
-func (p PGSQLProvider) validateUserAndPubKey(username string, publicKey string) (User, string, error) {
+func (p PGSQLProvider) validateUserAndPubKey(username string, publicKey []byte) (User, string, error) {
 	return sqlCommonValidateUserAndPubKey(username, publicKey, p.dbHandle)
 }
 
@@ -63,14 +99,14 @@ func (p PGSQLProvider) updateQuota(username string, filesAdd int, sizeAdd int64,
 	return sqlCommonUpdateQuota(username, filesAdd, sizeAdd, reset, p.dbHandle)
 }
 
-func (p PGSQLProvider) updateLastLogin(username string) error {
-	return sqlCommonUpdateLastLogin(username, p.dbHandle)
-}
-
 func (p PGSQLProvider) getUsedQuota(username string) (int, int64, error) {
 	return sqlCommonGetUsedQuota(username, p.dbHandle)
 }
 
+func (p PGSQLProvider) updateLastLogin(username string) error {
+	return sqlCommonUpdateLastLogin(username, p.dbHandle)
+}
+
 func (p PGSQLProvider) userExists(username string) (User, error) {
 	return sqlCommonCheckUserExists(username, p.dbHandle)
 }
@@ -95,6 +131,120 @@ func (p PGSQLProvider) getUsers(limit int, offset int, order string, username st
 	return sqlCommonGetUsers(limit, offset, order, username, p.dbHandle)
 }
 
+func (p PGSQLProvider) dumpFolders() ([]vfs.BaseVirtualFolder, error) {
+	return sqlCommonDumpFolders(p.dbHandle)
+}
+
+func (p PGSQLProvider) getFolders(limit, offset int, order, folderPath string) ([]vfs.BaseVirtualFolder, error) {
+	return sqlCommonGetFolders(limit, offset, order, folderPath, p.dbHandle)
+}
+
+func (p PGSQLProvider) getFolderByPath(mappedPath string) (vfs.BaseVirtualFolder, error) {
+	ctx, cancel := context.WithTimeout(context.Background(), defaultSQLQueryTimeout)
+	defer cancel()
+	return sqlCommonCheckFolderExists(ctx, mappedPath, p.dbHandle)
+}
+
+func (p PGSQLProvider) addFolder(folder vfs.BaseVirtualFolder) error {
+	return sqlCommonAddFolder(folder, p.dbHandle)
+}
+
+func (p PGSQLProvider) deleteFolder(folder vfs.BaseVirtualFolder) error {
+	return sqlCommonDeleteFolder(folder, p.dbHandle)
+}
+
+func (p PGSQLProvider) updateFolderQuota(mappedPath string, filesAdd int, sizeAdd int64, reset bool) error {
+	return sqlCommonUpdateFolderQuota(mappedPath, filesAdd, sizeAdd, reset, p.dbHandle)
+}
+
+func (p PGSQLProvider) getUsedFolderQuota(mappedPath string) (int, int64, error) {
+	return sqlCommonGetFolderUsedQuota(mappedPath, p.dbHandle)
+}
+
 func (p PGSQLProvider) close() error {
 	return p.dbHandle.Close()
 }
+
+func (p PGSQLProvider) reloadConfig() error {
+	return nil
+}
+
+// initializeDatabase creates the initial database structure
+func (p PGSQLProvider) initializeDatabase() error {
+	dbVersion, err := sqlCommonGetDatabaseVersion(p.dbHandle, false)
+	if err == nil && dbVersion.Version > 0 {
+		return ErrNoInitRequired
+	}
+	sqlUsers := strings.Replace(pgsqlUsersTableSQL, "{{users}}", sqlTableUsers, 1)
+	tx, err := p.dbHandle.Begin()
+	if err != nil {
+		return err
+	}
+	_, err = tx.Exec(sqlUsers)
+	if err != nil {
+		sqlCommonRollbackTransaction(tx)
+		return err
+	}
+	_, err = tx.Exec(strings.Replace(pgsqlSchemaTableSQL, "{{schema_version}}", sqlTableSchemaVersion, 1))
+	if err != nil {
+		sqlCommonRollbackTransaction(tx)
+		return err
+	}
+	_, err = tx.Exec(strings.Replace(initialDBVersionSQL, "{{schema_version}}", sqlTableSchemaVersion, 1))
+	if err != nil {
+		sqlCommonRollbackTransaction(tx)
+		return err
+	}
+	return tx.Commit()
+}
+
+func (p PGSQLProvider) migrateDatabase() error {
+	dbVersion, err := sqlCommonGetDatabaseVersion(p.dbHandle, true)
+	if err != nil {
+		return err
+	}
+	if dbVersion.Version == sqlDatabaseVersion {
+		providerLog(logger.LevelDebug, "sql database is up to date, current version: %v", dbVersion.Version)
+		return ErrNoInitRequired
+	}
+	switch dbVersion.Version {
+	case 1:
+		err = updatePGSQLDatabaseFrom1To2(p.dbHandle)
+		if err != nil {
+			return err
+		}
+		err = updatePGSQLDatabaseFrom2To3(p.dbHandle)
+		if err != nil {
+			return err
+		}
+		return updatePGSQLDatabaseFrom3To4(p.dbHandle)
+	case 2:
+		err = updatePGSQLDatabaseFrom2To3(p.dbHandle)
+		if err != nil {
+			return err
+		}
+		return updatePGSQLDatabaseFrom3To4(p.dbHandle)
+	case 3:
+		return updatePGSQLDatabaseFrom3To4(p.dbHandle)
+	default:
+		return fmt.Errorf("Database version not handled: %v", dbVersion.Version)
+	}
+}
+
+func updatePGSQLDatabaseFrom1To2(dbHandle *sql.DB) error {
+	logger.InfoToConsole("updating database version: 1 -> 2")
+	providerLog(logger.LevelInfo, "updating database version: 1 -> 2")
+	sql := strings.Replace(pgsqlV2SQL, "{{users}}", sqlTableUsers, 1)
+	return sqlCommonExecSQLAndUpdateDBVersion(dbHandle, []string{sql}, 2)
+}
+
+func updatePGSQLDatabaseFrom2To3(dbHandle *sql.DB) error {
+	logger.InfoToConsole("updating database version: 2 -> 3")
+	providerLog(logger.LevelInfo, "updating database version: 2 -> 3")
+	sql := strings.Replace(pgsqlV3SQL, "{{users}}", sqlTableUsers, 1)
+	return sqlCommonExecSQLAndUpdateDBVersion(dbHandle, []string{sql}, 3)
+}
+
+func updatePGSQLDatabaseFrom3To4(dbHandle *sql.DB) error {
+	return sqlCommonUpdateDatabaseFrom3To4(pgsqlV4SQL, dbHandle)
+}

dataprovider/pgsql_disabled.go

@@ -0,0 +1,17 @@
+// +build nopgsql
+
+package dataprovider
+
+import (
+	"errors"
+
+	"github.com/drakkan/sftpgo/version"
+)
+
+func init() {
+	version.AddFeature("-pgsql")
+}
+
+func initializePGSQLProvider() error {
+	return errors.New("PostgreSQL disabled at build time")
+}

dataprovider/sqlite.go

@@ -1,13 +1,68 @@
+// +build !nosqlite
+
 package dataprovider
 
 import (
+	"context"
 	"database/sql"
-	"errors"
 	"fmt"
-	"os"
 	"path/filepath"
+	"strings"
+
+	// we import go-sqlite3 here to be able to disable SQLite support using a build tag
+	_ "github.com/mattn/go-sqlite3"
 
 	"github.com/drakkan/sftpgo/logger"
+	"github.com/drakkan/sftpgo/utils"
+	"github.com/drakkan/sftpgo/version"
+	"github.com/drakkan/sftpgo/vfs"
+)
+
+const (
+	sqliteUsersTableSQL = `CREATE TABLE "{{users}}" ("id" integer NOT NULL PRIMARY KEY AUTOINCREMENT, "username" varchar(255)
+NOT NULL UNIQUE, "password" varchar(255) NULL, "public_keys" text NULL, "home_dir" varchar(255) NOT NULL, "uid" integer NOT NULL,
+"gid" integer NOT NULL, "max_sessions" integer NOT NULL, "quota_size" bigint NOT NULL, "quota_files" integer NOT NULL,
+"permissions" text NOT NULL, "used_quota_size" bigint NOT NULL, "used_quota_files" integer NOT NULL,
+"last_quota_update" bigint NOT NULL, "upload_bandwidth" integer NOT NULL, "download_bandwidth" integer NOT NULL,
+"expiration_date" bigint NOT NULL, "last_login" bigint NOT NULL, "status" integer NOT NULL, "filters" text NULL,
+"filesystem" text NULL);`
+	sqliteSchemaTableSQL = `CREATE TABLE "{{schema_version}}" ("id" integer NOT NULL PRIMARY KEY AUTOINCREMENT, "version" integer NOT NULL);`
+	sqliteV2SQL          = `ALTER TABLE "{{users}}" ADD COLUMN "virtual_folders" text NULL;`
+	sqliteV3SQL          = `CREATE TABLE "new__users" ("id" integer NOT NULL PRIMARY KEY AUTOINCREMENT, "username" varchar(255) NOT NULL UNIQUE,
+	"password" text NULL, "public_keys" text NULL, "home_dir" varchar(255) NOT NULL, "uid" integer NOT NULL,
+"gid" integer NOT NULL, "max_sessions" integer NOT NULL, "quota_size" bigint NOT NULL, "quota_files" integer NOT NULL,
+"permissions" text NOT NULL, "used_quota_size" bigint NOT NULL, "used_quota_files" integer NOT NULL, "last_quota_update" bigint NOT NULL,
+"upload_bandwidth" integer NOT NULL, "download_bandwidth" integer NOT NULL, "expiration_date" bigint NOT NULL, "last_login" bigint NOT NULL,
+"status" integer NOT NULL, "filters" text NULL, "filesystem" text NULL, "virtual_folders" text NULL);
+INSERT INTO "new__users" ("id", "username", "public_keys", "home_dir", "uid", "gid", "max_sessions", "quota_size", "quota_files",
+"permissions", "used_quota_size", "used_quota_files", "last_quota_update", "upload_bandwidth", "download_bandwidth", "expiration_date",
+"last_login", "status", "filters", "filesystem", "virtual_folders", "password") SELECT "id", "username", "public_keys", "home_dir",
+"uid", "gid", "max_sessions", "quota_size", "quota_files", "permissions", "used_quota_size", "used_quota_files", "last_quota_update",
+"upload_bandwidth", "download_bandwidth", "expiration_date", "last_login", "status", "filters", "filesystem", "virtual_folders",
+"password" FROM "{{users}}";
+DROP TABLE "{{users}}";
+ALTER TABLE "new__users" RENAME TO "{{users}}";`
+	sqliteV4SQL = `CREATE TABLE "{{folders}}" ("id" integer NOT NULL PRIMARY KEY AUTOINCREMENT, "path" varchar(512) NOT NULL UNIQUE,
+"used_quota_size" bigint NOT NULL, "used_quota_files" integer NOT NULL, "last_quota_update" bigint NOT NULL);
+CREATE TABLE "{{folders_mapping}}" ("id" integer NOT NULL PRIMARY KEY AUTOINCREMENT, "virtual_path" varchar(512) NOT NULL,
+"quota_size" bigint NOT NULL, "quota_files" integer NOT NULL, "folder_id" integer NOT NULL REFERENCES "{{folders}}" ("id")
+ON DELETE CASCADE DEFERRABLE INITIALLY DEFERRED, "user_id" integer NOT NULL REFERENCES "{{users}}" ("id") ON DELETE CASCADE DEFERRABLE INITIALLY DEFERRED,
+CONSTRAINT "unique_mapping" UNIQUE ("user_id", "folder_id"));
+CREATE TABLE "new__users" ("id" integer NOT NULL PRIMARY KEY AUTOINCREMENT, "username" varchar(255) NOT NULL UNIQUE, "password" text NULL,
+"public_keys" text NULL, "home_dir" varchar(512) NOT NULL, "uid" integer NOT NULL, "gid" integer NOT NULL, "max_sessions" integer NOT NULL,
+"quota_size" bigint NOT NULL, "quota_files" integer NOT NULL, "permissions" text NOT NULL, "used_quota_size" bigint NOT NULL,
+"used_quota_files" integer NOT NULL, "last_quota_update" bigint NOT NULL, "upload_bandwidth" integer NOT NULL, "download_bandwidth" integer NOT NULL,
+"expiration_date" bigint NOT NULL, "last_login" bigint NOT NULL, "status" integer NOT NULL, "filters" text NULL, "filesystem" text NULL);
+INSERT INTO "new__users" ("id", "username", "password", "public_keys", "home_dir", "uid", "gid", "max_sessions", "quota_size", "quota_files",
+"permissions", "used_quota_size", "used_quota_files", "last_quota_update", "upload_bandwidth", "download_bandwidth", "expiration_date",
+"last_login", "status", "filters", "filesystem") SELECT "id", "username", "password", "public_keys", "home_dir", "uid", "gid", "max_sessions",
+"quota_size", "quota_files", "permissions", "used_quota_size", "used_quota_files", "last_quota_update", "upload_bandwidth", "download_bandwidth",
+"expiration_date", "last_login", "status", "filters", "filesystem" FROM "{{users}}";
+DROP TABLE "{{users}}";
+ALTER TABLE "new__users" RENAME TO "{{users}}";
+CREATE INDEX "folders_mapping_folder_id_idx" ON "{{folders_mapping}}" ("folder_id");
+CREATE INDEX "folders_mapping_user_id_idx" ON "{{folders_mapping}}" ("user_id");
+`
 )
 
 // SQLiteProvider auth provider for SQLite database
@@ -15,26 +70,23 @@ type SQLiteProvider struct {
 	dbHandle *sql.DB
 }
 
+func init() {
+	version.AddFeature("+sqlite")
+}
+
 func initializeSQLiteProvider(basePath string) error {
 	var err error
 	var connectionString string
-	logSender = SQLiteDataProviderName
+	logSender = fmt.Sprintf("dataprovider_%v", SQLiteDataProviderName)
 	if len(config.ConnectionString) == 0 {
 		dbPath := config.Name
+		if !utils.IsFileInputValid(dbPath) {
+			return fmt.Errorf("Invalid database path: %#v", dbPath)
+		}
 		if !filepath.IsAbs(dbPath) {
 			dbPath = filepath.Join(basePath, dbPath)
 		}
-		fi, err := os.Stat(dbPath)
-		if err != nil {
-			providerLog(logger.LevelWarn, "sqlite database file does not exists, please be sure to create and initialize"+
-				" a database before starting sftpgo")
-			return err
-		}
-		if fi.Size() == 0 {
-			return errors.New("sqlite database file is invalid, please be sure to create and initialize" +
-				" a database before starting sftpgo")
-		}
-		connectionString = fmt.Sprintf("file:%v?cache=shared", dbPath)
+		connectionString = fmt.Sprintf("file:%v?cache=shared&_foreign_keys=1", dbPath)
 	} else {
 		connectionString = config.ConnectionString
 	}
@@ -54,11 +106,11 @@ func (p SQLiteProvider) checkAvailability() error {
 	return sqlCommonCheckAvailability(p.dbHandle)
 }
 
-func (p SQLiteProvider) validateUserAndPass(username string, password string) (User, error) {
-	return sqlCommonValidateUserAndPass(username, password, p.dbHandle)
+func (p SQLiteProvider) validateUserAndPass(username, password, ip, protocol string) (User, error) {
+	return sqlCommonValidateUserAndPass(username, password, ip, protocol, p.dbHandle)
 }
 
-func (p SQLiteProvider) validateUserAndPubKey(username string, publicKey string) (User, string, error) {
+func (p SQLiteProvider) validateUserAndPubKey(username string, publicKey []byte) (User, string, error) {
 	return sqlCommonValidateUserAndPubKey(username, publicKey, p.dbHandle)
 }
 
@@ -70,14 +122,14 @@ func (p SQLiteProvider) updateQuota(username string, filesAdd int, sizeAdd int64
 	return sqlCommonUpdateQuota(username, filesAdd, sizeAdd, reset, p.dbHandle)
 }
 
-func (p SQLiteProvider) updateLastLogin(username string) error {
-	return sqlCommonUpdateLastLogin(username, p.dbHandle)
-}
-
 func (p SQLiteProvider) getUsedQuota(username string) (int, int64, error) {
 	return sqlCommonGetUsedQuota(username, p.dbHandle)
 }
 
+func (p SQLiteProvider) updateLastLogin(username string) error {
+	return sqlCommonUpdateLastLogin(username, p.dbHandle)
+}
+
 func (p SQLiteProvider) userExists(username string) (User, error) {
 	return sqlCommonCheckUserExists(username, p.dbHandle)
 }
@@ -102,6 +154,120 @@ func (p SQLiteProvider) getUsers(limit int, offset int, order string, username s
 	return sqlCommonGetUsers(limit, offset, order, username, p.dbHandle)
 }
 
+func (p SQLiteProvider) dumpFolders() ([]vfs.BaseVirtualFolder, error) {
+	return sqlCommonDumpFolders(p.dbHandle)
+}
+
+func (p SQLiteProvider) getFolders(limit, offset int, order, folderPath string) ([]vfs.BaseVirtualFolder, error) {
+	return sqlCommonGetFolders(limit, offset, order, folderPath, p.dbHandle)
+}
+
+func (p SQLiteProvider) getFolderByPath(mappedPath string) (vfs.BaseVirtualFolder, error) {
+	ctx, cancel := context.WithTimeout(context.Background(), defaultSQLQueryTimeout)
+	defer cancel()
+	return sqlCommonCheckFolderExists(ctx, mappedPath, p.dbHandle)
+}
+
+func (p SQLiteProvider) addFolder(folder vfs.BaseVirtualFolder) error {
+	return sqlCommonAddFolder(folder, p.dbHandle)
+}
+
+func (p SQLiteProvider) deleteFolder(folder vfs.BaseVirtualFolder) error {
+	return sqlCommonDeleteFolder(folder, p.dbHandle)
+}
+
+func (p SQLiteProvider) updateFolderQuota(mappedPath string, filesAdd int, sizeAdd int64, reset bool) error {
+	return sqlCommonUpdateFolderQuota(mappedPath, filesAdd, sizeAdd, reset, p.dbHandle)
+}
+
+func (p SQLiteProvider) getUsedFolderQuota(mappedPath string) (int, int64, error) {
+	return sqlCommonGetFolderUsedQuota(mappedPath, p.dbHandle)
+}
+
 func (p SQLiteProvider) close() error {
 	return p.dbHandle.Close()
 }
+
+func (p SQLiteProvider) reloadConfig() error {
+	return nil
+}
+
+// initializeDatabase creates the initial database structure
+func (p SQLiteProvider) initializeDatabase() error {
+	dbVersion, err := sqlCommonGetDatabaseVersion(p.dbHandle, false)
+	if err == nil && dbVersion.Version > 0 {
+		return ErrNoInitRequired
+	}
+	sqlUsers := strings.Replace(sqliteUsersTableSQL, "{{users}}", sqlTableUsers, 1)
+	tx, err := p.dbHandle.Begin()
+	if err != nil {
+		return err
+	}
+	_, err = tx.Exec(sqlUsers)
+	if err != nil {
+		sqlCommonRollbackTransaction(tx)
+		return err
+	}
+	_, err = tx.Exec(strings.Replace(sqliteSchemaTableSQL, "{{schema_version}}", sqlTableSchemaVersion, 1))
+	if err != nil {
+		sqlCommonRollbackTransaction(tx)
+		return err
+	}
+	_, err = tx.Exec(strings.Replace(initialDBVersionSQL, "{{schema_version}}", sqlTableSchemaVersion, 1))
+	if err != nil {
+		sqlCommonRollbackTransaction(tx)
+		return err
+	}
+	return tx.Commit()
+}
+
+func (p SQLiteProvider) migrateDatabase() error {
+	dbVersion, err := sqlCommonGetDatabaseVersion(p.dbHandle, true)
+	if err != nil {
+		return err
+	}
+	if dbVersion.Version == sqlDatabaseVersion {
+		providerLog(logger.LevelDebug, "sql database is up to date, current version: %v", dbVersion.Version)
+		return ErrNoInitRequired
+	}
+	switch dbVersion.Version {
+	case 1:
+		err = updateSQLiteDatabaseFrom1To2(p.dbHandle)
+		if err != nil {
+			return err
+		}
+		err = updateSQLiteDatabaseFrom2To3(p.dbHandle)
+		if err != nil {
+			return err
+		}
+		return updateSQLiteDatabaseFrom3To4(p.dbHandle)
+	case 2:
+		err = updateSQLiteDatabaseFrom2To3(p.dbHandle)
+		if err != nil {
+			return err
+		}
+		return updateSQLiteDatabaseFrom3To4(p.dbHandle)
+	case 3:
+		return updateSQLiteDatabaseFrom3To4(p.dbHandle)
+	default:
+		return fmt.Errorf("Database version not handled: %v", dbVersion.Version)
+	}
+}
+
+func updateSQLiteDatabaseFrom1To2(dbHandle *sql.DB) error {
+	logger.InfoToConsole("updating database version: 1 -> 2")
+	providerLog(logger.LevelInfo, "updating database version: 1 -> 2")
+	sql := strings.Replace(sqliteV2SQL, "{{users}}", sqlTableUsers, 1)
+	return sqlCommonExecSQLAndUpdateDBVersion(dbHandle, []string{sql}, 2)
+}
+
+func updateSQLiteDatabaseFrom2To3(dbHandle *sql.DB) error {
+	logger.InfoToConsole("updating database version: 2 -> 3")
+	providerLog(logger.LevelInfo, "updating database version: 2 -> 3")
+	sql := strings.ReplaceAll(sqliteV3SQL, "{{users}}", sqlTableUsers)
+	return sqlCommonExecSQLAndUpdateDBVersion(dbHandle, []string{sql}, 3)
+}
+
+func updateSQLiteDatabaseFrom3To4(dbHandle *sql.DB) error {
+	return sqlCommonUpdateDatabaseFrom3To4(sqliteV4SQL, dbHandle)
+}

dataprovider/sqlite_disabled.go

@@ -0,0 +1,17 @@
+// +build nosqlite
+
+package dataprovider
+
+import (
+	"errors"
+
+	"github.com/drakkan/sftpgo/version"
+)
+
+func init() {
+	version.AddFeature("-sqlite")
+}
+
+func initializeSQLiteProvider(basePath string) error {
+	return errors.New("SQLite disabled at build time")
+}

dataprovider/sqlqueries.go

@@ -1,10 +1,17 @@
 package dataprovider
 
-import "fmt"
+import (
+	"fmt"
+	"strconv"
+	"strings"
+
+	"github.com/drakkan/sftpgo/vfs"
+)
 
 const (
 	selectUserFields = "id,username,password,public_keys,home_dir,uid,gid,max_sessions,quota_size,quota_files,permissions,used_quota_size," +
-		"used_quota_files,last_quota_update,upload_bandwidth,download_bandwidth,expiration_date,last_login,status,filters"
+		"used_quota_files,last_quota_update,upload_bandwidth,download_bandwidth,expiration_date,last_login,status,filters,filesystem"
+	selectFolderFields = "id,path,used_quota_size,used_quota_files,last_quota_update"
 )
 
 func getSQLPlaceholders() []string {
@@ -20,61 +27,160 @@ func getSQLPlaceholders() []string {
 }
 
 func getUserByUsernameQuery() string {
-	return fmt.Sprintf(`SELECT %v FROM %v WHERE username = %v`, selectUserFields, config.UsersTable, sqlPlaceholders[0])
+	return fmt.Sprintf(`SELECT %v FROM %v WHERE username = %v`, selectUserFields, sqlTableUsers, sqlPlaceholders[0])
 }
 
 func getUserByIDQuery() string {
-	return fmt.Sprintf(`SELECT %v FROM %v WHERE id = %v`, selectUserFields, config.UsersTable, sqlPlaceholders[0])
+	return fmt.Sprintf(`SELECT %v FROM %v WHERE id = %v`, selectUserFields, sqlTableUsers, sqlPlaceholders[0])
 }
 
 func getUsersQuery(order string, username string) string {
 	if len(username) > 0 {
 		return fmt.Sprintf(`SELECT %v FROM %v WHERE username = %v ORDER BY username %v LIMIT %v OFFSET %v`,
-			selectUserFields, config.UsersTable, sqlPlaceholders[0], order, sqlPlaceholders[1], sqlPlaceholders[2])
+			selectUserFields, sqlTableUsers, sqlPlaceholders[0], order, sqlPlaceholders[1], sqlPlaceholders[2])
 	}
-	return fmt.Sprintf(`SELECT %v FROM %v ORDER BY username %v LIMIT %v OFFSET %v`, selectUserFields, config.UsersTable,
+	return fmt.Sprintf(`SELECT %v FROM %v ORDER BY username %v LIMIT %v OFFSET %v`, selectUserFields, sqlTableUsers,
 		order, sqlPlaceholders[0], sqlPlaceholders[1])
 }
 
 func getDumpUsersQuery() string {
-	return fmt.Sprintf(`SELECT %v FROM %v`, selectUserFields, config.UsersTable)
+	return fmt.Sprintf(`SELECT %v FROM %v`, selectUserFields, sqlTableUsers)
+}
+
+func getDumpFoldersQuery() string {
+	return fmt.Sprintf(`SELECT %v FROM %v`, selectFolderFields, sqlTableFolders)
 }
 
 func getUpdateQuotaQuery(reset bool) string {
 	if reset {
 		return fmt.Sprintf(`UPDATE %v SET used_quota_size = %v,used_quota_files = %v,last_quota_update = %v
-			WHERE username = %v`, config.UsersTable, sqlPlaceholders[0], sqlPlaceholders[1], sqlPlaceholders[2], sqlPlaceholders[3])
+			WHERE username = %v`, sqlTableUsers, sqlPlaceholders[0], sqlPlaceholders[1], sqlPlaceholders[2], sqlPlaceholders[3])
 	}
 	return fmt.Sprintf(`UPDATE %v SET used_quota_size = used_quota_size + %v,used_quota_files = used_quota_files + %v,last_quota_update = %v
-		WHERE username = %v`, config.UsersTable, sqlPlaceholders[0], sqlPlaceholders[1], sqlPlaceholders[2], sqlPlaceholders[3])
+		WHERE username = %v`, sqlTableUsers, sqlPlaceholders[0], sqlPlaceholders[1], sqlPlaceholders[2], sqlPlaceholders[3])
 }
 
 func getUpdateLastLoginQuery() string {
-	return fmt.Sprintf(`UPDATE %v SET last_login = %v WHERE username = %v`, config.UsersTable, sqlPlaceholders[0], sqlPlaceholders[1])
+	return fmt.Sprintf(`UPDATE %v SET last_login = %v WHERE username = %v`, sqlTableUsers, sqlPlaceholders[0], sqlPlaceholders[1])
 }
 
 func getQuotaQuery() string {
-	return fmt.Sprintf(`SELECT used_quota_size,used_quota_files FROM %v WHERE username = %v`, config.UsersTable,
+	return fmt.Sprintf(`SELECT used_quota_size,used_quota_files FROM %v WHERE username = %v`, sqlTableUsers,
 		sqlPlaceholders[0])
 }
 
 func getAddUserQuery() string {
 	return fmt.Sprintf(`INSERT INTO %v (username,password,public_keys,home_dir,uid,gid,max_sessions,quota_size,quota_files,permissions,
-		used_quota_size,used_quota_files,last_quota_update,upload_bandwidth,download_bandwidth,status,last_login,expiration_date,filters)
-		VALUES (%v,%v,%v,%v,%v,%v,%v,%v,%v,%v,0,0,0,%v,%v,%v,0,%v,%v)`, config.UsersTable, sqlPlaceholders[0], sqlPlaceholders[1],
+		used_quota_size,used_quota_files,last_quota_update,upload_bandwidth,download_bandwidth,status,last_login,expiration_date,filters,
+		filesystem)
+		VALUES (%v,%v,%v,%v,%v,%v,%v,%v,%v,%v,0,0,0,%v,%v,%v,0,%v,%v,%v)`, sqlTableUsers, sqlPlaceholders[0], sqlPlaceholders[1],
 		sqlPlaceholders[2], sqlPlaceholders[3], sqlPlaceholders[4], sqlPlaceholders[5], sqlPlaceholders[6], sqlPlaceholders[7],
 		sqlPlaceholders[8], sqlPlaceholders[9], sqlPlaceholders[10], sqlPlaceholders[11], sqlPlaceholders[12], sqlPlaceholders[13],
-		sqlPlaceholders[14])
+		sqlPlaceholders[14], sqlPlaceholders[15])
 }
 
 func getUpdateUserQuery() string {
 	return fmt.Sprintf(`UPDATE %v SET password=%v,public_keys=%v,home_dir=%v,uid=%v,gid=%v,max_sessions=%v,quota_size=%v,
-		quota_files=%v,permissions=%v,upload_bandwidth=%v,download_bandwidth=%v,status=%v,expiration_date=%v,filters=%v WHERE id = %v`,
-		config.UsersTable, sqlPlaceholders[0], sqlPlaceholders[1], sqlPlaceholders[2], sqlPlaceholders[3], sqlPlaceholders[4],
-		sqlPlaceholders[5], sqlPlaceholders[6], sqlPlaceholders[7], sqlPlaceholders[8], sqlPlaceholders[9], sqlPlaceholders[10],
-		sqlPlaceholders[11], sqlPlaceholders[12], sqlPlaceholders[13], sqlPlaceholders[14])
+		quota_files=%v,permissions=%v,upload_bandwidth=%v,download_bandwidth=%v,status=%v,expiration_date=%v,filters=%v,filesystem=%v
+		WHERE id = %v`, sqlTableUsers, sqlPlaceholders[0], sqlPlaceholders[1], sqlPlaceholders[2], sqlPlaceholders[3],
+		sqlPlaceholders[4], sqlPlaceholders[5], sqlPlaceholders[6], sqlPlaceholders[7], sqlPlaceholders[8], sqlPlaceholders[9],
+		sqlPlaceholders[10], sqlPlaceholders[11], sqlPlaceholders[12], sqlPlaceholders[13], sqlPlaceholders[14], sqlPlaceholders[15])
 }
 
 func getDeleteUserQuery() string {
-	return fmt.Sprintf(`DELETE FROM %v WHERE id = %v`, config.UsersTable, sqlPlaceholders[0])
+	return fmt.Sprintf(`DELETE FROM %v WHERE id = %v`, sqlTableUsers, sqlPlaceholders[0])
+}
+
+func getFolderByPathQuery() string {
+	return fmt.Sprintf(`SELECT %v FROM %v WHERE path = %v`, selectFolderFields, sqlTableFolders, sqlPlaceholders[0])
+}
+
+func getAddFolderQuery() string {
+	return fmt.Sprintf(`INSERT INTO %v (path,used_quota_size,used_quota_files,last_quota_update) VALUES (%v,%v,%v,%v)`,
+		sqlTableFolders, sqlPlaceholders[0], sqlPlaceholders[1], sqlPlaceholders[2], sqlPlaceholders[3])
+}
+
+func getDeleteFolderQuery() string {
+	return fmt.Sprintf(`DELETE FROM %v WHERE id = %v`, sqlTableFolders, sqlPlaceholders[0])
+}
+
+func getClearFolderMappingQuery() string {
+	return fmt.Sprintf(`DELETE FROM %v WHERE user_id = (SELECT id FROM %v WHERE username = %v)`, sqlTableFoldersMapping,
+		sqlTableUsers, sqlPlaceholders[0])
+}
+
+func getAddFolderMappingQuery() string {
+	return fmt.Sprintf(`INSERT INTO %v (virtual_path,quota_size,quota_files,folder_id,user_id)
+		VALUES (%v,%v,%v,%v,(SELECT id FROM %v WHERE username = %v))`, sqlTableFoldersMapping, sqlPlaceholders[0],
+		sqlPlaceholders[1], sqlPlaceholders[2], sqlPlaceholders[3], sqlTableUsers, sqlPlaceholders[4])
+}
+
+func getFoldersQuery(order, folderPath string) string {
+	if len(folderPath) > 0 {
+		return fmt.Sprintf(`SELECT %v FROM %v WHERE path = %v ORDER BY path %v LIMIT %v OFFSET %v`,
+			selectFolderFields, sqlTableFolders, sqlPlaceholders[0], order, sqlPlaceholders[1], sqlPlaceholders[2])
+	}
+	return fmt.Sprintf(`SELECT %v FROM %v ORDER BY path %v LIMIT %v OFFSET %v`, selectFolderFields, sqlTableFolders,
+		order, sqlPlaceholders[0], sqlPlaceholders[1])
+}
+
+func getUpdateFolderQuotaQuery(reset bool) string {
+	if reset {
+		return fmt.Sprintf(`UPDATE %v SET used_quota_size = %v,used_quota_files = %v,last_quota_update = %v
+			WHERE path = %v`, sqlTableFolders, sqlPlaceholders[0], sqlPlaceholders[1], sqlPlaceholders[2], sqlPlaceholders[3])
+	}
+	return fmt.Sprintf(`UPDATE %v SET used_quota_size = used_quota_size + %v,used_quota_files = used_quota_files + %v,last_quota_update = %v
+		WHERE path = %v`, sqlTableFolders, sqlPlaceholders[0], sqlPlaceholders[1], sqlPlaceholders[2], sqlPlaceholders[3])
+}
+
+func getQuotaFolderQuery() string {
+	return fmt.Sprintf(`SELECT used_quota_size,used_quota_files FROM %v WHERE path = %v`, sqlTableFolders,
+		sqlPlaceholders[0])
+}
+
+func getRelatedFoldersForUsersQuery(users []User) string {
+	var sb strings.Builder
+	for _, u := range users {
+		if sb.Len() == 0 {
+			sb.WriteString("(")
+		} else {
+			sb.WriteString(",")
+		}
+		sb.WriteString(strconv.FormatInt(u.ID, 10))
+	}
+	if sb.Len() > 0 {
+		sb.WriteString(")")
+	}
+	return fmt.Sprintf(`SELECT f.id,f.path,f.used_quota_size,f.used_quota_files,f.last_quota_update,fm.virtual_path,fm.quota_size,fm.quota_files,fm.user_id
+		FROM %v f INNER JOIN %v fm ON f.id = fm.folder_id WHERE fm.user_id IN %v ORDER BY fm.user_id`, sqlTableFolders,
+		sqlTableFoldersMapping, sb.String())
+}
+
+func getRelatedUsersForFoldersQuery(folders []vfs.BaseVirtualFolder) string {
+	var sb strings.Builder
+	for _, f := range folders {
+		if sb.Len() == 0 {
+			sb.WriteString("(")
+		} else {
+			sb.WriteString(",")
+		}
+		sb.WriteString(strconv.FormatInt(f.ID, 10))
+	}
+	if sb.Len() > 0 {
+		sb.WriteString(")")
+	}
+	return fmt.Sprintf(`SELECT fm.folder_id,u.username FROM %v fm INNER JOIN %v u ON fm.user_id = u.id
+		WHERE fm.folder_id IN %v ORDER BY fm.folder_id`, sqlTableFoldersMapping, sqlTableUsers, sb.String())
+}
+
+func getDatabaseVersionQuery() string {
+	return fmt.Sprintf("SELECT version from %v LIMIT 1", sqlTableSchemaVersion)
+}
+
+func getUpdateDBVersionQuery() string {
+	return fmt.Sprintf(`UPDATE %v SET version=%v`, sqlTableSchemaVersion, sqlPlaceholders[0])
+}
+
+func getCompatVirtualFoldersQuery() string {
+	return fmt.Sprintf(`SELECT id,username,virtual_folders FROM %v`, sqlTableUsers)
 }

dataprovider/user.go

@@ -2,15 +2,19 @@ package dataprovider
 
 import (
 	"encoding/json"
+	"errors"
 	"fmt"
 	"net"
+	"os"
 	"path"
 	"path/filepath"
 	"strconv"
 	"strings"
+	"time"
 
 	"github.com/drakkan/sftpgo/logger"
 	"github.com/drakkan/sftpgo/utils"
+	"github.com/drakkan/sftpgo/vfs"
 )
 
 // Available permissions for SFTP users
@@ -42,18 +46,97 @@ const (
 	PermChtimes = "chtimes"
 )
 
+// Available login methods
+const (
+	LoginMethodNoAuthTryed            = "no_auth_tryed"
+	LoginMethodPassword               = "password"
+	SSHLoginMethodPublicKey           = "publickey"
+	SSHLoginMethodKeyboardInteractive = "keyboard-interactive"
+	SSHLoginMethodKeyAndPassword      = "publickey+password"
+	SSHLoginMethodKeyAndKeyboardInt   = "publickey+keyboard-interactive"
+)
+
+var (
+	errNoMatchingVirtualFolder = errors.New("no matching virtual folder found")
+)
+
+// CachedUser adds fields useful for caching to a SFTPGo user
+type CachedUser struct {
+	User       User
+	Expiration time.Time
+	Password   string
+}
+
+// IsExpired returns true if the cached user is expired
+func (c CachedUser) IsExpired() bool {
+	if c.Expiration.IsZero() {
+		return false
+	}
+	return c.Expiration.Before(time.Now())
+}
+
+// ExtensionsFilter defines filters based on file extensions.
+// These restrictions do not apply to files listing for performance reasons, so
+// a denied file cannot be downloaded/overwritten/renamed but will still be
+// it will still be listed in the list of files.
+// System commands such as Git and rsync interacts with the filesystem directly
+// and they are not aware about these restrictions so they are not allowed
+// inside paths with extensions filters
+type ExtensionsFilter struct {
+	// SFTP/SCP path, if no other specific filter is defined, the filter apply for
+	// sub directories too.
+	// For example if filters are defined for the paths "/" and "/sub" then the
+	// filters for "/" are applied for any file outside the "/sub" directory
+	Path string `json:"path"`
+	// only files with these, case insensitive, extensions are allowed.
+	// Shell like expansion is not supported so you have to specify ".jpg" and
+	// not "*.jpg"
+	AllowedExtensions []string `json:"allowed_extensions,omitempty"`
+	// files with these, case insensitive, extensions are not allowed.
+	// Denied file extensions are evaluated before the allowed ones
+	DeniedExtensions []string `json:"denied_extensions,omitempty"`
+}
+
 // UserFilters defines additional restrictions for a user
 type UserFilters struct {
 	// only clients connecting from these IP/Mask are allowed.
 	// IP/Mask must be in CIDR notation as defined in RFC 4632 and RFC 4291
 	// for example "192.0.2.0/24" or "2001:db8::/32"
-	AllowedIP []string `json:"allowed_ip"`
+	AllowedIP []string `json:"allowed_ip,omitempty"`
 	// clients connecting from these IP/Mask are not allowed.
 	// Denied rules will be evaluated before allowed ones
-	DeniedIP []string `json:"denied_ip"`
+	DeniedIP []string `json:"denied_ip,omitempty"`
+	// these login methods are not allowed.
+	// If null or empty any available login method is allowed
+	DeniedLoginMethods []string `json:"denied_login_methods,omitempty"`
+	// these protocols are not allowed.
+	// If null or empty any available protocol is allowed
+	DeniedProtocols []string `json:"denied_protocols,omitempty"`
+	// filters based on file extensions.
+	// Please note that these restrictions can be easily bypassed.
+	FileExtensions []ExtensionsFilter `json:"file_extensions,omitempty"`
+	// max size allowed for a single upload, 0 means unlimited
+	MaxUploadFileSize int64 `json:"max_upload_file_size,omitempty"`
 }
 
-// User defines an SFTP user
+// FilesystemProvider defines the supported storages
+type FilesystemProvider int
+
+// supported values for FilesystemProvider
+const (
+	LocalFilesystemProvider FilesystemProvider = iota // Local
+	S3FilesystemProvider                              // Amazon S3 compatible
+	GCSFilesystemProvider                             // Google Cloud Storage
+)
+
+// Filesystem defines cloud storage filesystem details
+type Filesystem struct {
+	Provider  FilesystemProvider `json:"provider"`
+	S3Config  vfs.S3FsConfig     `json:"s3config,omitempty"`
+	GCSConfig vfs.GCSFsConfig    `json:"gcsconfig,omitempty"`
+}
+
+// User defines a SFTPGo user
 type User struct {
 	// Database unique identifier
 	ID int64 `json:"id"`
@@ -66,12 +149,15 @@ type User struct {
 	ExpirationDate int64 `json:"expiration_date"`
 	// Password used for password authentication.
 	// For users created using SFTPGo REST API the password is be stored using argon2id hashing algo.
-	// Checking passwords stored with bcrypt, pbkdf2 and sha512crypt is supported too.
+	// Checking passwords stored with bcrypt, pbkdf2, md5crypt and sha512crypt is supported too.
 	Password string `json:"password,omitempty"`
 	// PublicKeys used for public key authentication. At least one between password and a public key is mandatory
 	PublicKeys []string `json:"public_keys,omitempty"`
 	// The user cannot upload or download files outside this directory. Must be an absolute path
 	HomeDir string `json:"home_dir"`
+	// Mapping between virtual paths and filesystem paths outside the home directory.
+	// Supported for local filesystem only
+	VirtualFolders []vfs.VirtualFolder `json:"virtual_folders,omitempty"`
 	// If sftpgo runs as root system user then the created files and directories will be assigned to this system UID
 	UID int `json:"uid"`
 	// If sftpgo runs as root system user then the created files and directories will be assigned to this system GID
@@ -98,6 +184,20 @@ type User struct {
 	LastLogin int64 `json:"last_login"`
 	// Additional restrictions
 	Filters UserFilters `json:"filters"`
+	// Filesystem configuration details
+	FsConfig Filesystem `json:"filesystem"`
+}
+
+// GetFilesystem returns the filesystem for this user
+func (u *User) GetFilesystem(connectionID string) (vfs.Fs, error) {
+	if u.FsConfig.Provider == S3FilesystemProvider {
+		return vfs.NewS3Fs(connectionID, u.GetHomeDir(), u.FsConfig.S3Config)
+	} else if u.FsConfig.Provider == GCSFilesystemProvider {
+		config := u.FsConfig.GCSConfig
+		config.CredentialFile = u.getGCSCredentialsFilePath()
+		return vfs.NewGCSFs(connectionID, u.GetHomeDir(), config)
+	}
+	return vfs.NewOsFs(connectionID, u.GetHomeDir(), u.VirtualFolders), nil
 }
 
 // GetPermissionsForPath returns the permissions for the given path.
@@ -112,19 +212,7 @@ func (u *User) GetPermissionsForPath(p string) []string {
 		// fallback permissions
 		permissions = perms
 	}
-	sftpPath := filepath.ToSlash(p)
-	if !path.IsAbs(p) {
-		sftpPath = "/" + sftpPath
-	}
-	sftpPath = path.Clean(sftpPath)
-	dirsForPath := []string{sftpPath}
-	for {
-		if sftpPath == "/" {
-			break
-		}
-		sftpPath = path.Dir(sftpPath)
-		dirsForPath = append(dirsForPath, sftpPath)
-	}
+	dirsForPath := utils.GetDirsForSFTPPath(p)
 	// dirsForPath contains all the dirs for a given path in reverse order
 	// for example if the path is: /1/2/3/4 it contains:
 	// [ "/1/2/3/4", "/1/2/3", "/1/2", "/1", "/" ]
@@ -138,6 +226,118 @@ func (u *User) GetPermissionsForPath(p string) []string {
 	return permissions
 }
 
+// GetVirtualFolderForPath returns the virtual folder containing the specified sftp path.
+// If the path is not inside a virtual folder an error is returned
+func (u *User) GetVirtualFolderForPath(sftpPath string) (vfs.VirtualFolder, error) {
+	var folder vfs.VirtualFolder
+	if len(u.VirtualFolders) == 0 || u.FsConfig.Provider != LocalFilesystemProvider {
+		return folder, errNoMatchingVirtualFolder
+	}
+	dirsForPath := utils.GetDirsForSFTPPath(sftpPath)
+	for _, val := range dirsForPath {
+		for _, v := range u.VirtualFolders {
+			if v.VirtualPath == val {
+				return v, nil
+			}
+		}
+	}
+	return folder, errNoMatchingVirtualFolder
+}
+
+// AddVirtualDirs adds virtual folders, if defined, to the given files list
+func (u *User) AddVirtualDirs(list []os.FileInfo, sftpPath string) []os.FileInfo {
+	if len(u.VirtualFolders) == 0 {
+		return list
+	}
+	for _, v := range u.VirtualFolders {
+		if path.Dir(v.VirtualPath) == sftpPath {
+			fi := vfs.NewFileInfo(v.VirtualPath, true, 0, time.Now(), false)
+			found := false
+			for index, f := range list {
+				if f.Name() == fi.Name() {
+					list[index] = fi
+					found = true
+					break
+				}
+			}
+			if !found {
+				list = append(list, fi)
+			}
+		}
+	}
+	return list
+}
+
+// IsMappedPath returns true if the specified filesystem path has a virtual folder mapping.
+// The filesystem path must be cleaned before calling this method
+func (u *User) IsMappedPath(fsPath string) bool {
+	for _, v := range u.VirtualFolders {
+		if fsPath == v.MappedPath {
+			return true
+		}
+	}
+	return false
+}
+
+// IsVirtualFolder returns true if the specified sftp path is a virtual folder
+func (u *User) IsVirtualFolder(sftpPath string) bool {
+	for _, v := range u.VirtualFolders {
+		if sftpPath == v.VirtualPath {
+			return true
+		}
+	}
+	return false
+}
+
+// HasVirtualFoldersInside returns true if there are virtual folders inside the
+// specified SFTP path. We assume that path are cleaned
+func (u *User) HasVirtualFoldersInside(sftpPath string) bool {
+	if sftpPath == "/" && len(u.VirtualFolders) > 0 {
+		return true
+	}
+	for _, v := range u.VirtualFolders {
+		if len(v.VirtualPath) > len(sftpPath) {
+			if strings.HasPrefix(v.VirtualPath, sftpPath+"/") {
+				return true
+			}
+		}
+	}
+	return false
+}
+
+// HasPermissionsInside returns true if the specified sftpPath has no permissions itself and
+// no subdirs with defined permissions
+func (u *User) HasPermissionsInside(sftpPath string) bool {
+	for dir := range u.Permissions {
+		if dir == sftpPath {
+			return true
+		} else if len(dir) > len(sftpPath) {
+			if strings.HasPrefix(dir, sftpPath+"/") {
+				return true
+			}
+		}
+	}
+	return false
+}
+
+// HasOverlappedMappedPaths returns true if this user has virtual folders with overlapped mapped paths
+func (u *User) HasOverlappedMappedPaths() bool {
+	if len(u.VirtualFolders) <= 1 {
+		return false
+	}
+	for _, v1 := range u.VirtualFolders {
+		for _, v2 := range u.VirtualFolders {
+			if v1.VirtualPath == v2.VirtualPath {
+				continue
+			}
+			if isMappedDirOverlapped(v1.MappedPath, v2.MappedPath) {
+				return true
+			}
+		}
+	}
+	return false
+}
+
 // HasPerm returns true if the user has the given permission or any permission
 func (u *User) HasPerm(permission, path string) bool {
 	perms := u.GetPermissionsForPath(path)
@@ -161,11 +361,121 @@ func (u *User) HasPerms(permissions []string, path string) bool {
 	return true
 }
 
-// IsLoginAllowed return true if the login is allowed from the specified remoteAddr.
+// HasNoQuotaRestrictions returns true if no quota restrictions need to be applyed
+func (u *User) HasNoQuotaRestrictions(checkFiles bool) bool {
+	if u.QuotaSize == 0 && (!checkFiles || u.QuotaFiles == 0) {
+		return true
+	}
+	return false
+}
+
+// IsLoginMethodAllowed returns true if the specified login method is allowed
+func (u *User) IsLoginMethodAllowed(loginMethod string, partialSuccessMethods []string) bool {
+	if len(u.Filters.DeniedLoginMethods) == 0 {
+		return true
+	}
+	if len(partialSuccessMethods) == 1 {
+		for _, method := range u.GetNextAuthMethods(partialSuccessMethods, true) {
+			if method == loginMethod {
+				return true
+			}
+		}
+	}
+	if utils.IsStringInSlice(loginMethod, u.Filters.DeniedLoginMethods) {
+		return false
+	}
+	return true
+}
+
+// GetNextAuthMethods returns the list of authentications methods that
+// can continue for multi-step authentication
+func (u *User) GetNextAuthMethods(partialSuccessMethods []string, isPasswordAuthEnabled bool) []string {
+	var methods []string
+	if len(partialSuccessMethods) != 1 {
+		return methods
+	}
+	if partialSuccessMethods[0] != SSHLoginMethodPublicKey {
+		return methods
+	}
+	for _, method := range u.GetAllowedLoginMethods() {
+		if method == SSHLoginMethodKeyAndPassword && isPasswordAuthEnabled {
+			methods = append(methods, LoginMethodPassword)
+		}
+		if method == SSHLoginMethodKeyAndKeyboardInt {
+			methods = append(methods, SSHLoginMethodKeyboardInteractive)
+		}
+	}
+	return methods
+}
+
+// IsPartialAuth returns true if the specified login method is a step for
+// a multi-step Authentication.
+// We support publickey+password and publickey+keyboard-interactive, so
+// only publickey can returns partial success.
+// We can have partial success if only multi-step Auth methods are enabled
+func (u *User) IsPartialAuth(loginMethod string) bool {
+	if loginMethod != SSHLoginMethodPublicKey {
+		return false
+	}
+	for _, method := range u.GetAllowedLoginMethods() {
+		if !utils.IsStringInSlice(method, SSHMultiStepsLoginMethods) {
+			return false
+		}
+	}
+	return true
+}
+
+// GetAllowedLoginMethods returns the allowed login methods
+func (u *User) GetAllowedLoginMethods() []string {
+	var allowedMethods []string
+	for _, method := range ValidSSHLoginMethods {
+		if !utils.IsStringInSlice(method, u.Filters.DeniedLoginMethods) {
+			allowedMethods = append(allowedMethods, method)
+		}
+	}
+	return allowedMethods
+}
+
+// IsFileAllowed returns true if the specified file is allowed by the file restrictions filters
+func (u *User) IsFileAllowed(sftpPath string) bool {
+	if len(u.Filters.FileExtensions) == 0 {
+		return true
+	}
+	dirsForPath := utils.GetDirsForSFTPPath(path.Dir(sftpPath))
+	var filter ExtensionsFilter
+	for _, dir := range dirsForPath {
+		for _, f := range u.Filters.FileExtensions {
+			if f.Path == dir {
+				filter = f
+				break
+			}
+		}
+		if len(filter.Path) > 0 {
+			break
+		}
+	}
+	if len(filter.Path) > 0 {
+		toMatch := strings.ToLower(sftpPath)
+		for _, denied := range filter.DeniedExtensions {
+			if strings.HasSuffix(toMatch, denied) {
+				return false
+			}
+		}
+		for _, allowed := range filter.AllowedExtensions {
+			if strings.HasSuffix(toMatch, allowed) {
+				return true
+			}
+		}
+		return len(filter.AllowedExtensions) == 0
+	}
+	return true
+}
+
+// IsLoginFromAddrAllowed returns true if the login is allowed from the specified remoteAddr.
 // If AllowedIP is defined only the specified IP/Mask can login.
 // If DeniedIP is defined the specified IP/Mask cannot login.
 // If an IP is both allowed and denied then login will be denied
-func (u *User) IsLoginAllowed(remoteAddr string) bool {
+func (u *User) IsLoginFromAddrAllowed(remoteAddr string) bool {
 	if len(u.Filters.AllowedIP) == 0 && len(u.Filters.DeniedIP) == 0 {
 		return true
 	}
@@ -211,6 +521,11 @@ func (u *User) GetFiltersAsJSON() ([]byte, error) {
 	return json.Marshal(u.Filters)
 }
 
+// GetFsConfigAsJSON returns the filesystem config as json byte array
+func (u *User) GetFsConfigAsJSON() ([]byte, error) {
+	return json.Marshal(u.FsConfig)
+}
+
 // GetUID returns a validate uid, suitable for use with os.Chown
 func (u *User) GetUID() int {
 	if u.UID <= 0 || u.UID > 65535 {
@@ -237,19 +552,6 @@ func (u *User) HasQuotaRestrictions() bool {
 	return u.QuotaFiles > 0 || u.QuotaSize > 0
 }
 
-// GetRelativePath returns the path for a file relative to the user's home dir.
-// This is the path as seen by SFTP users
-func (u *User) GetRelativePath(path string) string {
-	rel, err := filepath.Rel(u.GetHomeDir(), filepath.Clean(path))
-	if err != nil {
-		return ""
-	}
-	if rel == "." || strings.HasPrefix(rel, "..") {
-		rel = ""
-	}
-	return "/" + filepath.ToSlash(rel)
-}
-
 // GetQuotaSummary returns used quota and limits if defined
 func (u *User) GetQuotaSummary() string {
 	var result string
@@ -300,25 +602,31 @@ func (u *User) GetBandwidthAsString() string {
 	if u.DownloadBandwidth > 0 {
 		result += utils.ByteCountSI(u.DownloadBandwidth*1000) + "/s."
 	} else {
-		result += "ulimited."
+		result += "unlimited."
 	}
 	result += " Upload: "
 	if u.UploadBandwidth > 0 {
 		result += utils.ByteCountSI(u.UploadBandwidth*1000) + "/s."
 	} else {
-		result += "ulimited."
+		result += "unlimited."
 	}
 	return result
 }
 
 // GetInfoString returns user's info as string.
-// Number of public keys, max sessions, uid and gid are returned
+// Storage provider, number of public keys, max sessions, uid,
+// gid, denied and allowed IP/Mask are returned
 func (u *User) GetInfoString() string {
 	var result string
 	if u.LastLogin > 0 {
 		t := utils.GetTimeFromMsecSinceEpoch(u.LastLogin)
 		result += fmt.Sprintf("Last login: %v ", t.Format("2006-01-02 15:04:05")) // YYYY-MM-DD HH:MM:SS
 	}
+	if u.FsConfig.Provider == S3FilesystemProvider {
+		result += "Storage: S3 "
+	} else if u.FsConfig.Provider == GCSFilesystemProvider {
+		result += "Storage: GCS "
+	}
 	if len(u.PublicKeys) > 0 {
 		result += fmt.Sprintf("Public keys: %v ", len(u.PublicKeys))
 	}
@@ -376,6 +684,8 @@ func (u User) GetDeniedIPAsString() string {
 func (u *User) getACopy() User {
 	pubKeys := make([]string, len(u.PublicKeys))
 	copy(pubKeys, u.PublicKeys)
+	virtualFolders := make([]vfs.VirtualFolder, len(u.VirtualFolders))
+	copy(virtualFolders, u.VirtualFolders)
 	permissions := make(map[string][]string)
 	for k, v := range u.Permissions {
 		perms := make([]string, len(v))
@@ -383,10 +693,38 @@ func (u *User) getACopy() User {
 		permissions[k] = perms
 	}
 	filters := UserFilters{}
+	filters.MaxUploadFileSize = u.Filters.MaxUploadFileSize
 	filters.AllowedIP = make([]string, len(u.Filters.AllowedIP))
 	copy(filters.AllowedIP, u.Filters.AllowedIP)
 	filters.DeniedIP = make([]string, len(u.Filters.DeniedIP))
 	copy(filters.DeniedIP, u.Filters.DeniedIP)
+	filters.DeniedLoginMethods = make([]string, len(u.Filters.DeniedLoginMethods))
+	copy(filters.DeniedLoginMethods, u.Filters.DeniedLoginMethods)
+	filters.FileExtensions = make([]ExtensionsFilter, len(u.Filters.FileExtensions))
+	copy(filters.FileExtensions, u.Filters.FileExtensions)
+	filters.DeniedProtocols = make([]string, len(u.Filters.DeniedProtocols))
+	copy(filters.DeniedProtocols, u.Filters.DeniedProtocols)
+	fsConfig := Filesystem{
+		Provider: u.FsConfig.Provider,
+		S3Config: vfs.S3FsConfig{
+			Bucket:            u.FsConfig.S3Config.Bucket,
+			Region:            u.FsConfig.S3Config.Region,
+			AccessKey:         u.FsConfig.S3Config.AccessKey,
+			AccessSecret:      u.FsConfig.S3Config.AccessSecret,
+			Endpoint:          u.FsConfig.S3Config.Endpoint,
+			StorageClass:      u.FsConfig.S3Config.StorageClass,
+			KeyPrefix:         u.FsConfig.S3Config.KeyPrefix,
+			UploadPartSize:    u.FsConfig.S3Config.UploadPartSize,
+			UploadConcurrency: u.FsConfig.S3Config.UploadConcurrency,
+		},
+		GCSConfig: vfs.GCSFsConfig{
+			Bucket:               u.FsConfig.GCSConfig.Bucket,
+			CredentialFile:       u.FsConfig.GCSConfig.CredentialFile,
+			AutomaticCredentials: u.FsConfig.GCSConfig.AutomaticCredentials,
+			StorageClass:         u.FsConfig.GCSConfig.StorageClass,
+			KeyPrefix:            u.FsConfig.GCSConfig.KeyPrefix,
+		},
+	}
 
 	return User{
 		ID:                u.ID,
@@ -394,6 +732,7 @@ func (u *User) getACopy() User {
 		Password:          u.Password,
 		PublicKeys:        pubKeys,
 		HomeDir:           u.HomeDir,
+		VirtualFolders:    virtualFolders,
 		UID:               u.UID,
 		GID:               u.GID,
 		MaxSessions:       u.MaxSessions,
@@ -409,6 +748,7 @@ func (u *User) getACopy() User {
 		ExpirationDate:    u.ExpirationDate,
 		LastLogin:         u.LastLogin,
 		Filters:           filters,
+		FsConfig:          fsConfig,
 	}
 }
 
@@ -416,7 +756,7 @@ func (u *User) getNotificationFieldsAsSlice(action string) []string {
 	return []string{action, u.Username,
 		strconv.FormatInt(u.ID, 10),
 		strconv.FormatInt(int64(u.Status), 10),
-		strconv.FormatInt(int64(u.ExpirationDate), 10),
+		strconv.FormatInt(u.ExpirationDate, 10),
 		u.HomeDir,
 		strconv.FormatInt(int64(u.UID), 10),
 		strconv.FormatInt(int64(u.GID), 10),
@@ -426,10 +766,21 @@ func (u *User) getNotificationFieldsAsSlice(action string) []string {
 func (u *User) getNotificationFieldsAsEnvVars(action string) []string {
 	return []string{fmt.Sprintf("SFTPGO_USER_ACTION=%v", action),
 		fmt.Sprintf("SFTPGO_USER_USERNAME=%v", u.Username),
+		fmt.Sprintf("SFTPGO_USER_PASSWORD=%v", u.Password),
 		fmt.Sprintf("SFTPGO_USER_ID=%v", u.ID),
 		fmt.Sprintf("SFTPGO_USER_STATUS=%v", u.Status),
 		fmt.Sprintf("SFTPGO_USER_EXPIRATION_DATE=%v", u.ExpirationDate),
 		fmt.Sprintf("SFTPGO_USER_HOME_DIR=%v", u.HomeDir),
 		fmt.Sprintf("SFTPGO_USER_UID=%v", u.UID),
-		fmt.Sprintf("SFTPGO_USER_GID=%v", u.GID)}
+		fmt.Sprintf("SFTPGO_USER_GID=%v", u.GID),
+		fmt.Sprintf("SFTPGO_USER_QUOTA_FILES=%v", u.QuotaFiles),
+		fmt.Sprintf("SFTPGO_USER_QUOTA_SIZE=%v", u.QuotaSize),
+		fmt.Sprintf("SFTPGO_USER_UPLOAD_BANDWIDTH=%v", u.UploadBandwidth),
+		fmt.Sprintf("SFTPGO_USER_DOWNLOAD_BANDWIDTH=%v", u.DownloadBandwidth),
+		fmt.Sprintf("SFTPGO_USER_MAX_SESSIONS=%v", u.MaxSessions),
+		fmt.Sprintf("SFTPGO_USER_FS_PROVIDER=%v", u.FsConfig.Provider)}
+}
+
+func (u *User) getGCSCredentialsFilePath() string {
+	return filepath.Join(credentialsDirPath, fmt.Sprintf("%v_gcs_credentials.json", u.Username))
 }

docker/README.md

@@ -1,5 +1,57 @@
-## Dockerfile examples
+# Official Docker images
 
-Sample Dockerfiles for `sftpgo` daemon and the REST API CLI.
+SFTPGo provides official Docker images. They are available on [Docker Hub](https://hub.docker.com/r/drakkan/sftpgo).
 
-We don't want to add a `Dockerfile` for each single `sftpgo` configuration options or data provider. You can use the docker configurations here as starting point that you can customize to run `sftpgo` with [Docker](http://www.docker.io "Docker").
+## Start a SFTPGo server instance
+
+Starting a SFTPGo instance is simple:
+
+```shell
+docker run --name some-sftpgo -p 127.0.0.1:8080:8080 -p 2022:2022 -d "drakkan/sftpgo:edge"
+```
+
+Now visit [http://localhost:8080/](http://localhost:8080/) and create a new SFTPGo user. The SFTP service is available on port 2022.
+
+## LOG
+
+The logs are available through Docker's container log:
+
+```shell
+docker logs some-sftpgo
+```
+
+## Where to Store Data
+
+Important note: There are several ways to store data used by applications that run in Docker containers. We encourage users of the SFTPGo images to familiarize themselves with the options available, including:
+
+- Let Docker manage the storage for SFTPGo data by [writing them to disk on the host system using its own internal volume management](https://docs.docker.com/engine/tutorials/dockervolumes/#adding-a-data-volume). This is the default and is easy and fairly transparent to the user. The downside is that the files may be hard to locate for tools and applications that run directly on the host system, i.e. outside containers.
+- Create a data directory on the host system (outside the container) and [mount this to a directory visible from inside the container]((https://docs.docker.com/engine/tutorials/dockervolumes/#mount-a-host-directory-as-a-data-volume)). This places the SFTPGo files in a known location on the host system, and makes it easy for tools and applications on the host system to access the files. The downside is that the user needs to make sure that the directory exists, and that e.g. directory permissions and other security mechanisms on the host system are set up correctly. The SFTPGo images run using `1000` as uid and gid.
+
+The Docker documentation is a good starting point for understanding the different storage options and variations, and there are multiple blogs and forum postings that discuss and give advice in this area. We will simply show the basic procedure here for the latter option above:
+
+1. Create a data directory on a suitable volume on your host system, e.g. `/my/own/sftpgodata`.
+2. Create a home directory for the sftpgo container user on your host system e.g. `/my/own/sftpgohome`.
+3. Start your SFTPGo container like this:
+
+```shell
+docker run --name some-sftpgo \
+    -p 127.0.0.1:8080:8090 \
+    -p 2022:2022 \
+    --mount type=bind,source=/my/own/sftpgodata,target=/srv/sftpgo \
+    --mount type=bind,source=/my/own/sftpgohome,target=/var/lib/sftpgo \
+    -e SFTPGO_HTTPD__BIND_PORT=8090 \
+    -d "drakkan/sftpgo:edge"
+```
+
+As you can see SFTPGo uses two volumes:
+
+- `/srv/sftpgo` to handle persistent data. The default home directory for SFTP/FTP/WebDAV users is `/srv/sftpgo/data/<username>`. Backups are stored in `/srv/sftpgo/backups`
+- `/var/lib/sftpgo` is the home directory for the sftpgo system user defined inside the container. This is the container working directory too, host keys will be created here when using the default configuration.
+
+## Configuration
+
+The runtime configuration can be customized via environment variables that you can set passing the `-e` option to the `docker run` command or inside the `environment` section if you are using [docker stack deploy](https://docs.docker.com/engine/reference/commandline/stack_deploy/) or [docker-compose](https://github.com/docker/compose).
+
+Please take a look [here](../docs/full-configuration.md#environment-variables) to learn how to configure SFTPGo via environment variables.
+
+Alternately you can mount your custom configuration file to `/var/lib/sftpgo` or `/var/lib/sftpgo/.config/sftpgo`.

docker/rest-api-cli/Dockerfile

@@ -2,7 +2,7 @@ FROM debian:latest
 LABEL maintainer="nicola.murino@gmail.com"
 RUN apt-get update && apt-get install -y curl python3-requests python3-pygments
 
-RUN curl https://raw.githubusercontent.com/drakkan/sftpgo/master/scripts/sftpgo_api_cli.py --output /usr/bin/sftpgo_api_cli.py
+RUN curl https://raw.githubusercontent.com/drakkan/sftpgo/master/examples/rest-api-cli/sftpgo_api_cli --output /usr/bin/sftpgo_api_cli
 
-ENTRYPOINT ["python3", "/usr/bin/sftpgo_api_cli.py" ]
+ENTRYPOINT ["python3", "/usr/bin/sftpgo_api_cli" ]
 CMD []

docker/sftpgo/alpine/Dockerfile

@@ -1,18 +1,20 @@
 FROM golang:alpine as builder
 
 RUN apk add --no-cache git gcc g++ ca-certificates \
-  && go get -d github.com/drakkan/sftpgo
+  && go get -v -d github.com/drakkan/sftpgo
 WORKDIR /go/src/github.com/drakkan/sftpgo
-# uncomment the next line to get the latest stable version instead of the latest git
-#RUN git checkout `git rev-list --tags --max-count=1`
-RUN go build -i -ldflags "-s -w -X github.com/drakkan/sftpgo/utils.commit=`git describe --always --dirty` -X github.com/drakkan/sftpgo/utils.date=`date -u +%FT%TZ`" -o /go/bin/sftpgo
+ARG TAG
+ARG FEATURES
+# Use --build-arg TAG=LATEST for latest tag. Use e.g. --build-arg TAG=v1.0.0 for a specific tag/commit. Otherwise HEAD (master) is built.
+RUN git checkout $(if [ "${TAG}" = LATEST ]; then echo `git rev-list --tags --max-count=1`; elif [ -n "${TAG}" ]; then echo "${TAG}"; else echo HEAD; fi)
+RUN go build $(if [ -n "${FEATURES}" ]; then echo "-tags ${FEATURES}"; fi) -ldflags "-s -w -X github.com/drakkan/sftpgo/version.commit=`git describe --always --dirty` -X github.com/drakkan/sftpgo/version.date=`date -u +%FT%TZ`" -v -o /go/bin/sftpgo
 
 FROM alpine:latest
 
 RUN apk add --no-cache ca-certificates su-exec \
   && mkdir -p /data /etc/sftpgo /srv/sftpgo/config /srv/sftpgo/web /srv/sftpgo/backups
 
-# git and rsync are optional, uncomment the next line to add support for them if needed
+# git and rsync are optional, uncomment the next line to add support for them if needed.
 #RUN apk add --no-cache git rsync
 
 COPY --from=builder /go/bin/sftpgo /bin/
@@ -25,5 +27,24 @@ RUN chmod +x /bin/entrypoint.sh
 VOLUME [ "/data", "/srv/sftpgo/config", "/srv/sftpgo/backups" ]
 EXPOSE 2022 8080
 
+# uncomment the following settings to enable FTP support
+#ENV SFTPGO_FTPD__BIND_PORT=2121
+#ENV SFTPGO_FTPD__FORCE_PASSIVE_IP=<your FTP visibile IP here>
+#EXPOSE 2121
+
+# we need to expose the passive ports range too
+#EXPOSE 50000-50100
+
+# it is a good idea to provide certificates to enable FTPS too
+#ENV SFTPGO_FTPD__CERTIFICATE_FILE=/srv/sftpgo/config/mycert.crt
+#ENV SFTPGO_FTPD__CERTIFICATE_KEY_FILE=/srv/sftpgo/config/mycert.key
+
+# uncomment the following setting to enable WebDAV support
+#ENV SFTPGO_WEBDAVD__BIND_PORT=8090
+
+# it is a good idea to provide certificates to enable WebDAV over HTTPS
+#ENV SFTPGO_WEBDAVD__CERTIFICATE_FILE=${CONFIG_DIR}/mycert.crt
+#ENV SFTPGO_WEBDAVD__CERTIFICATE_KEY_FILE=${CONFIG_DIR}/mycert.key
+
 ENTRYPOINT ["/bin/entrypoint.sh"]
-CMD []
+CMD ["serve"]

docker/sftpgo/alpine/README.md

@@ -1,26 +1,38 @@
 # SFTPGo with Docker and Alpine
 
+:warning: The recommended way to run SFTPGo on Docker is to use the official [images](https://hub.docker.com/r/drakkan/sftpgo). The documentation here is now obsolete.
+
 This DockerFile is made to build image to host multiple instances of SFTPGo started with different users.
 
-### Example
+## Example
+
 > 1003 is a custom uid:gid for this instance of SFTPGo
+
 ```bash
 # Prereq on docker host
 sudo groupadd -g 1003 sftpgrp && \
   sudo useradd -u 1003 -g 1003 sftpuser -d /home/sftpuser/ && \
   sudo -u sftpuser mkdir /home/sftpuser/{conf,data} && \
-  curl https://raw.githubusercontent.com/drakkan/sftpgo/master/sql/sqlite/20190828.sql | sqlite3 /home/sftpuser/conf/sftpgo.db && \
-  curl https://raw.githubusercontent.com/drakkan/sftpgo/master/sql/sqlite/20191112.sql | sqlite3 /home/sftpuser/conf/sftpgo.db && \
-  curl https://raw.githubusercontent.com/drakkan/sftpgo/master/sql/sqlite/20191230.sql | sqlite3 /home/sftpuser/conf/sftpgo.db && \
   curl https://raw.githubusercontent.com/drakkan/sftpgo/master/sftpgo.json -o /home/sftpuser/conf/sftpgo.json
 
-# Get and build SFTPGo image
+# Edit sftpgo.json as you need
+
+# Get and build SFTPGo image.
+# Add --build-arg TAG=LATEST to build the latest tag or e.g. TAG=v1.0.0 for a specific tag/commit.
+# Add --build-arg FEATURES=<build features comma separated> to specify the features to build.
 git clone https://github.com/drakkan/sftpgo.git && \
   cd sftpgo && \
   sudo docker build -t sftpgo docker/sftpgo/alpine/
 
-# Starting image
+# Initialize the configured provider. For PostgreSQL and MySQL providers you need to create the configured database and the "initprovider" command will create the required tables.
 sudo docker run --name sftpgo \
+  -e PUID=1003 \
+  -e GUID=1003 \
+  -v /home/sftpuser/conf/:/srv/sftpgo/config \
+  sftpgo initprovider -c /srv/sftpgo/config
+
+# Start the image
+sudo docker rm sftpgo && sudo docker run --name sftpgo \
   -e SFTPGO_LOG_FILE_PATH= \
   -e SFTPGO_CONFIG_DIR=/srv/sftpgo/config \
   -e SFTPGO_HTTPD__TEMPLATES_PATH=/srv/sftpgo/web/templates \
@@ -35,11 +47,15 @@ sudo docker run --name sftpgo \
   -v /home/sftpuser/backups:/srv/sftpgo/backups \
   sftpgo
 ```
-The script `entrypoint.sh` makes sure to correct the permissions of directories and start the process with the right user
+
+If you want to enable FTP/S you also need the publish the FTP port and the FTP passive port range, defined in your `Dockerfile`, by adding, for example, the following options to the `docker run` command `-p 2121:2121 -p 50000-50100:50000-50100`. The same goes for WebDAV, you need to publish the configured port.
+
+The script `entrypoint.sh` makes sure to correct the permissions of directories and start the process with the right user.
 
 Several images can be run with different parameters.
 
-### Custom systemd script
+## Custom systemd script
+
 An example of systemd script is present [here](sftpgo.service), with `Environment` parameter to set `PUID` and `GUID`
 
-`WorkingDirectory` parameter must be exist with one file in this directory like `sftpgo-${PUID}.env` corresponding to the variable file for SFTPGo instance.
+`WorkingDirectory` parameter must be exist with one file in this directory like `sftpgo-${PUID}.env` corresponding to the variable file for SFTPGo instance.

docker/sftpgo/alpine/docker-entrypoint.sh

@@ -4,4 +4,4 @@ set -eu
 
 chown -R "${PUID}:${GUID}" /data /etc/sftpgo /srv/sftpgo/config /srv/sftpgo/backups \
 	&& exec su-exec "${PUID}:${GUID}" \
-  /bin/sftpgo serve "$@"
+  /bin/sftpgo "$@"

docker/sftpgo/alpine/sftpgo.service

@@ -1,5 +1,5 @@
 [Unit]
-Description=SFTPGo sftp server
+Description=SFTPGo server
 After=docker.service
 
 [Service]
@@ -8,19 +8,23 @@ Group=root
 WorkingDirectory=/etc/sftpgo
 Environment=PUID=1003
 Environment=GUID=1003
-EnvironmentFile=-/etc/sysconfig/sftpgo.conf
+EnvironmentFile=-/etc/sysconfig/sftpgo.env
 ExecStartPre=-docker kill sftpgo
 ExecStartPre=-docker rm sftpgo
 ExecStart=docker run --name sftpgo \
   --env-file sftpgo-${PUID}.env \
   -e PUID=${PUID} \
   -e GUID=${GUID} \
+  -e SFTPGO_LOG_FILE_PATH= \
+  -e SFTPGO_CONFIG_DIR=/srv/sftpgo/config \
   -e SFTPGO_HTTPD__TEMPLATES_PATH=/srv/sftpgo/web/templates \
   -e SFTPGO_HTTPD__STATIC_FILES_PATH=/srv/sftpgo/web/static \
+  -e SFTPGO_HTTPD__BACKUPS_PATH=/srv/sftpgo/backups \
   -p 8080:8080 \
   -p 2022:2022 \
   -v /home/sftpuser/conf/:/srv/sftpgo/config \
   -v /home/sftpuser/data:/data \
+  -v /home/sftpuser/backups:/srv/sftpgo/backups \
   sftpgo
 ExecStop=docker stop sftpgo
 SyslogIdentifier=sftpgo

docker/sftpgo/debian/Dockerfile

@@ -1,17 +1,22 @@
 # we use a multi stage build to have a separate build and run env
 FROM golang:latest as buildenv
 LABEL maintainer="nicola.murino@gmail.com"
-RUN go get -d github.com/drakkan/sftpgo
+RUN go get -v -d github.com/drakkan/sftpgo
 WORKDIR /go/src/github.com/drakkan/sftpgo
-# uncomment the next line to get the latest stable version instead of the latest git
-#RUN git checkout `git rev-list --tags --max-count=1`
-RUN go build -i -ldflags "-s -w -X github.com/drakkan/sftpgo/utils.commit=`git describe --always --dirty` -X github.com/drakkan/sftpgo/utils.date=`date -u +%FT%TZ`" -o sftpgo
+ARG TAG
+ARG FEATURES
+# Use --build-arg TAG=LATEST for latest tag. Use e.g. --build-arg TAG=v1.0.0 for a specific tag/commit. Otherwise HEAD (master) is built.
+RUN git checkout $(if [ "${TAG}" = LATEST ]; then echo `git rev-list --tags --max-count=1`; elif [ -n "${TAG}" ]; then echo "${TAG}"; else echo HEAD; fi)
+RUN go build $(if [ -n "${FEATURES}" ]; then echo "-tags ${FEATURES}"; fi) -ldflags "-s -w -X github.com/drakkan/sftpgo/version.commit=`git describe --always --dirty` -X github.com/drakkan/sftpgo/version.date=`date -u +%FT%TZ`" -v -o sftpgo
 
 # now define the run environment
 FROM debian:latest
 
-# git and rsync are optional, uncomment the next line to add support for them if needed
-#RUN apt-get update && apt-get install -y git rsync
+# ca-certificates is needed for Cloud Storage Support and for HTTPS/FTPS.
+RUN apt-get update && apt-get install -y ca-certificates && apt-get clean
+
+# git and rsync are optional, uncomment the next line to add support for them if needed.
+#RUN apt-get update && apt-get install -y git rsync && apt-get clean
 
 ARG BASE_DIR=/app
 ARG DATA_REL_DIR=data
@@ -35,7 +40,7 @@ ENV WEB_DIR=${BASE_DIR}/${WEB_REL_PATH}
 
 RUN mkdir -p ${DATA_DIR} ${CONFIG_DIR} ${WEB_DIR} ${BACKUPS_DIR}
 RUN groupadd --system -g ${GID} ${GROUPNAME}
-RUN useradd --system --create-home --no-log-init --home-dir ${HOME_DIR} --comment "SFTPGo user" --shell /bin/false --gid ${GID} --uid ${UID} ${USERNAME}
+RUN useradd --system --create-home --no-log-init --home-dir ${HOME_DIR} --comment "SFTPGo user" --shell /usr/sbin/nologin --gid ${GID} --uid ${UID} ${USERNAME}
 
 WORKDIR ${HOME_DIR}
 RUN mkdir -p bin .config/sftpgo
@@ -59,12 +64,30 @@ VOLUME [ "$DATA_DIR", "$CONFIG_DIR", "$BACKUPS_DIR" ]
 # override some default configuration options using env vars
 ENV SFTPGO_CONFIG_DIR=${CONFIG_DIR}
 # setting SFTPGO_LOG_FILE_PATH to an empty string will log to stdout
-ENV SFTPGO_LOG_FILE_PATH=${CONFIG_DIR}/sftpgo.log
+ENV SFTPGO_LOG_FILE_PATH=""
 ENV SFTPGO_HTTPD__BIND_ADDRESS=""
 ENV SFTPGO_HTTPD__TEMPLATES_PATH=${WEB_DIR}/templates
 ENV SFTPGO_HTTPD__STATIC_FILES_PATH=${WEB_DIR}/static
 ENV SFTPGO_DATA_PROVIDER__USERS_BASE_DIR=${DATA_DIR}
 ENV SFTPGO_HTTPD__BACKUPS_PATH=${BACKUPS_DIR}
 
+# uncomment the following settings to enable FTP support
+#ENV SFTPGO_FTPD__BIND_PORT=2121
+#ENV SFTPGO_FTPD__FORCE_PASSIVE_IP=<your FTP visibile IP here>
+#EXPOSE 2121
+# we need to expose the passive ports range too
+#EXPOSE 50000-50100
+
+# it is a good idea to provide certificates to enable FTPS too
+#ENV SFTPGO_FTPD__CERTIFICATE_FILE=${CONFIG_DIR}/mycert.crt
+#ENV SFTPGO_FTPD__CERTIFICATE_KEY_FILE=${CONFIG_DIR}/mycert.key
+
+# uncomment the following setting to enable WebDAV support
+#ENV SFTPGO_WEBDAVD__BIND_PORT=8090
+
+# it is a good idea to provide certificates to enable WebDAV over HTTPS
+#ENV SFTPGO_WEBDAVD__CERTIFICATE_FILE=${CONFIG_DIR}/mycert.crt
+#ENV SFTPGO_WEBDAVD__CERTIFICATE_KEY_FILE=${CONFIG_DIR}/mycert.key
+
 ENTRYPOINT ["sftpgo"]
-CMD ["serve"]
+CMD ["serve"]

docker/sftpgo/debian/README.md

@@ -1,4 +1,6 @@
-## Dockerfile based on Debian stable
+# Dockerfile based on Debian stable
+
+:warning: The recommended way to run SFTPGo on Docker is to use the official [images](https://hub.docker.com/r/drakkan/sftpgo). The documentation here is now obsolete.
 
 Please read the comments inside the `Dockerfile` to learn how to customize things for your setup.
 
@@ -8,15 +10,50 @@ You can build the container image using `docker build`, for example:
 docker build -t="drakkan/sftpgo" .
 ```
 
-and you can run the Dockerfile using something like this:
+This will build master of github.com/drakkan/sftpgo.
+
+To build the latest tag you can add `--build-arg TAG=LATEST` and to build a specific tag/commit you can use for example `TAG=v1.0.0`, like this:
 
 ```bash
-docker run --name sftpgo -p 8080:8080 -p 2022:2022 --mount type=bind,source=/srv/sftpgo/data,target=/app/data --mount type=bind,source=/srv/sftpgo/config,target=/app/config --mount type=bind,source=/srv/sftpgo/backups,target=/app/backups drakkan/sftpgo
+docker build -t="drakkan/sftpgo" --build-arg TAG=v1.0.0 .
 ```
 
-where  `/srv/sftpgo/data`, `/srv/sftpgo/config` and `/srv/sftpgo/backups` are folders on the host system with write access for UID/GID defined inside the `Dockerfile`. You can choose to create a new user, on the host system, with a matching UID/GID pair or simply do something like:
-
+To specify the features to build you can add `--build-arg FEATURES=<build features comma separated>`. For example you can disable SQLite and S3 support like this:
 
 ```bash
-chown -R <UID>:<GID> /srv/sftpgo/data /srv/sftpgo/config /srv/sftpgo/backups
-```
+docker build -t="drakkan/sftpgo" --build-arg FEATURES=nosqlite,nos3 .
+```
+
+Please take a look at the [build from source](./../../../docs/build-from-source.md) documentation for the complete list of the features that can be disabled.
+
+Now create the required folders on the host system, for example:
+
+```bash
+sudo mkdir -p /srv/sftpgo/data /srv/sftpgo/config /srv/sftpgo/backups
+```
+
+and give write access to them to the UID/GID defined inside the `Dockerfile`. You can choose to create a new user, on the host system, with a matching UID/GID pair, or simply do something like this:
+
+```bash
+sudo chown -R <UID>:<GID> /srv/sftpgo/data /srv/sftpgo/config /srv/sftpgo/backups
+```
+
+Download the default configuration file and edit it as you need:
+
+```bash
+sudo curl https://raw.githubusercontent.com/drakkan/sftpgo/master/sftpgo.json -o /srv/sftpgo/config/sftpgo.json
+```
+
+Initialize the configured provider. For PostgreSQL and MySQL providers you need to create the configured database and the `initprovider` command will create the required tables:
+
+```bash
+docker run --name sftpgo --mount type=bind,source=/srv/sftpgo/config,target=/app/config drakkan/sftpgo initprovider -c /app/config
+```
+
+and finally you can run the image using something like this:
+
+```bash
+docker rm sftpgo && docker run --name sftpgo -p 8080:8080 -p 2022:2022 --mount type=bind,source=/srv/sftpgo/data,target=/app/data --mount type=bind,source=/srv/sftpgo/config,target=/app/config --mount type=bind,source=/srv/sftpgo/backups,target=/app/backups drakkan/sftpgo
+```
+
+If you want to enable FTP/S you also need the publish the FTP port and the FTP passive port range, defined in your `Dockerfile`, by adding, for example, the following options to the `docker run` command `-p 2121:2121 -p 50000-50100:50000-50100`. The same goes for WebDAV, you need to publish the configured port.

docs/account.md

@@ -0,0 +1,70 @@
+# Account's configuration properties
+
+For each account, the following properties can be configured:
+
+- `username`
+- `password` used for password authentication. For users created using SFTPGo REST API, if the password has no known hashing algo prefix, it will be stored using argon2id. SFTPGo supports checking passwords stored with bcrypt, pbkdf2, md5crypt and sha512crypt too. For pbkdf2 the supported format is `$<algo>$<iterations>$<salt>$<hashed pwd base64 encoded>`, where algo is `pbkdf2-sha1` or `pbkdf2-sha256` or `pbkdf2-sha512` or `$pbkdf2-b64salt-sha256$`. For example the `pbkdf2-sha256` of the word `password` using 150000 iterations and `E86a9YMX3zC7` as salt must be stored as `$pbkdf2-sha256$150000$E86a9YMX3zC7$R5J62hsSq+pYw00hLLPKBbcGXmq7fj5+/M0IFoYtZbo=`. In pbkdf2 variant with `b64salt` the salt is base64 encoded. For bcrypt the format must be the one supported by golang's [crypto/bcrypt](https://godoc.org/golang.org/x/crypto/bcrypt) package, for example the password `secret` with cost `14` must be stored as `$2a$14$ajq8Q7fbtFRQvXpdCq7Jcuy.Rx1h/L4J60Otx.gyNLbAYctGMJ9tK`. For md5crypt and sha512crypt we support the format used in `/etc/shadow` with the `$1$` and `$6$` prefix, this is useful if you are migrating from Unix system user accounts. We support Apache md5crypt (`$apr1$` prefix) too. Using the REST API you can send a password hashed as bcrypt, pbkdf2, md5crypt or sha512crypt and it will be stored as is.
+- `public_keys` array of public keys. At least one public key or the password is mandatory.
+- `status` 1 means "active", 0 "inactive". An inactive account cannot login.
+- `expiration_date` expiration date as unix timestamp in milliseconds. An expired account cannot login. 0 means no expiration.
+- `home_dir` the user cannot upload or download files outside this directory. Must be an absolute path. A local home directory is required for Cloud Storage Backends too: in this case it will store temporary files.
+- `virtual_folders` list of mappings between virtual SFTP/SCP paths and local filesystem paths outside the user home directory. More information can be found [here](./virtual-folders.md)
+- `uid`, `gid`. If SFTPGo runs as root system user then the created files and directories will be assigned to this system uid/gid. Ignored on windows or if SFTPGo runs as non root user: in this case files and directories for all SFTP users will be owned by the system user that runs SFTPGo.
+- `max_sessions` maximum concurrent sessions. 0 means unlimited.
+- `quota_size` maximum size allowed as bytes. 0 means unlimited.
+- `quota_files` maximum number of files allowed. 0 means unlimited.
+- `permissions` for SFTP paths. The following per directory permissions are supported:
+  - `*` all permissions are granted
+  - `list` list items is allowed
+  - `download` download files is allowed
+  - `upload` upload files is allowed
+  - `overwrite` overwrite an existing file, while uploading, is allowed. `upload` permission is required to allow file overwrite
+  - `delete` delete files or directories is allowed
+  - `rename` rename a file or a directory is allowed if this permission is granted on source and target path. You can enable rename in a more controlled way granting `delete` permission on source directory and `upload`/`create_dirs`/`create_symlinks` permissions on target directory
+  - `create_dirs` create directories is allowed
+  - `create_symlinks` create symbolic links is allowed
+  - `chmod` changing file or directory permissions is allowed. On Windows, only the 0200 bit (owner writable) of mode is used; it controls whether the file's read-only attribute is set or cleared. The other bits are currently unused. Use mode 0400 for a read-only file and 0600 for a readable+writable file.
+  - `chown` changing file or directory owner and group is allowed. Changing owner and group is not supported on Windows.
+  - `chtimes` changing file or directory access and modification time is allowed
+- `upload_bandwidth` maximum upload bandwidth as KB/s, 0 means unlimited.
+- `download_bandwidth` maximum download bandwidth as KB/s, 0 means unlimited.
+- `allowed_ip`, List of IP/Mask allowed to login. Any IP address not contained in this list cannot login. IP/Mask must be in CIDR notation as defined in RFC 4632 and RFC 4291, for example "192.0.2.0/24" or "2001:db8::/32"
+- `denied_ip`, List of IP/Mask not allowed to login. If an IP address is both allowed and denied then login will be denied
+- `max_upload_file_size`, max allowed size, as bytes, for a single file upload. The upload will be aborted if/when the size of the file being sent exceeds this limit. 0 means unlimited. This restriction does not apply for SSH system commands such as `git` and `rsync`
+- `denied_login_methods`, List of login methods not allowed. To enable multi-step authentication you have to allow only multi-step login methods. If password login method is denied or no password is set then FTP and WebDAV users cannot login. The following login methods are supported:
+  - `publickey`
+  - `password`
+  - `keyboard-interactive`
+  - `publickey+password`
+  - `publickey+keyboard-interactive`
+- `denied_protocols`, list of protocols not allowed. The following protocols are supported:
+  - `SSH`
+  - `FTP`
+  - `DAV`
+- `file_extensions`, list of struct. These restrictions do not apply to files listing for performance reasons, so a denied file cannot be downloaded/overwritten/renamed but it will still be listed in the list of files. Please note that these restrictions can be easily bypassed. Each struct contains the following fields:
+  - `allowed_extensions`, list of, case insensitive, allowed files extension. Shell like expansion is not supported so you have to specify `.jpg` and not `*.jpg`. Any file that does not end with this suffix will be denied
+  - `denied_extensions`, list of, case insensitive, denied files extension. Denied file extensions are evaluated before the allowed ones
+  - `path`, SFTP/SCP path, if no other specific filter is defined, the filter apply for sub directories too. For example if filters are defined for the paths `/` and `/sub` then the filters for `/` are applied for any file outside the `/sub` directory
+- `fs_provider`, filesystem to serve via SFTP. Local filesystem and S3 Compatible Object Storage are supported
+- `s3_bucket`, required for S3 filesystem
+- `s3_region`, required for S3 filesystem. Must match the region for your bucket. You can find here the list of available [AWS regions](https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/using-regions-availability-zones.html#concepts-available-regions). For example if your bucket is at `Frankfurt` you have to set the region to `eu-central-1`
+- `s3_access_key`
+- `s3_access_secret`, if provided it is stored encrypted (AES-256-GCM). You can leave access key and access secret blank to use credentials from environment
+- `s3_endpoint`, specifies a S3 endpoint (server) different from AWS. It is not required if you are connecting to AWS
+- `s3_storage_class`, leave blank to use the default or specify a valid AWS [storage class](https://docs.aws.amazon.com/AmazonS3/latest/dev/storage-class-intro.html)
+- `s3_key_prefix`, allows to restrict access to the folder identified by this prefix and its contents
+- `s3_upload_part_size`, the buffer size for multipart uploads (MB). Zero means the default (5 MB). Minimum is 5
+- `s3_upload_concurrency` how many parts are uploaded in parallel
+- `gcs_bucket`, required for GCS filesystem
+- `gcs_credentials`, Google Cloud Storage JSON credentials base64 encoded
+- `gcs_automatic_credentials`, integer. Set to 1 to use Application Default Credentials strategy or set to 0 to use explicit credentials via `gcs_credentials`
+- `gcs_storage_class`
+- `gcs_key_prefix`, allows to restrict access to the folder identified by this prefix and its contents
+
+These properties are stored inside the data provider.
+
+If you want to use your existing accounts, you have these options:
+
+- If your accounts are already stored inside a supported database, you can create a database view. Since a view is read only, you have to disable user management and quota tracking so SFTPGo will never try to write to the view
+- you can import your users inside SFTPGo. Take a look at [sftpgo_api_cli](../examples/rest-api-cli#convert-users-from-other-stores "SFTPGo API CLI example"), it can convert and import users from Linux system users and Pure-FTPd/ProFTPD virtual users
+- you can use an external authentication program

docs/build-from-source.md

@@ -0,0 +1,47 @@
+# Build SFTPGo from source
+
+You can install the package to your [\$GOPATH](https://github.com/golang/go/wiki/GOPATH "GOPATH") with the [go tool](https://golang.org/cmd/go/ "go command") from shell:
+
+```bash
+go get -u github.com/drakkan/sftpgo
+```
+
+Or you can download the sources and use `go build`.
+
+Make sure [Git](https://git-scm.com/downloads) is installed on your machine and in your system's `PATH`.
+
+The following build tags are available:
+
+- `nogcs`, disable Google Cloud Storage backend, default enabled
+- `nos3`, disable S3 Compabible Object Storage backends, default enabled
+- `nobolt`, disable Bolt data provider, default enabled
+- `nomysql`, disable MySQL data provider, default enabled
+- `nopgsql`, disable PostgreSQL data provider, default enabled
+- `nosqlite`, disable SQLite data provider, default enabled
+- `noportable`, disable portable mode, default enabled
+- `nometrics`, disable Prometheus metrics, default enabled
+
+If no build tag is specified the build will include the default features.
+
+The optional [SQLite driver](https://github.com/mattn/go-sqlite3 "go-sqlite3") is a `CGO` package and so it requires a `C` compiler at build time.
+On Linux and macOS, a compiler is easy to install or already installed. On Windows, you need to download [MinGW-w64](https://sourceforge.net/projects/mingw-w64/files/) and build SFTPGo from its command prompt.
+
+The compiler is a build time only dependency. It is not required at runtime.
+
+Version info, such as git commit and build date, can be embedded setting the following string variables at build time:
+
+- `github.com/drakkan/sftpgo/version.commit`
+- `github.com/drakkan/sftpgo/version.date`
+
+For example, you can build using the following command:
+
+```bash
+go build -tags nogcs,nos3,nosqlite -ldflags "-s -w -X github.com/drakkan/sftpgo/version.commit=`git describe --always --dirty` -X github.com/drakkan/sftpgo/version.date=`date -u +%FT%TZ`" -o sftpgo
+```
+
+You should get a version that includes git commit, build date and available features like this one:
+
+```bash
+$ ./sftpgo -v
+SFTPGo 0.9.6-dev-b30614e-dirty-2020-06-19T11:04:56Z +metrics -gcs -s3 +bolt +mysql +pgsql -sqlite +portable
+```

docs/check-password-hook.md

@@ -0,0 +1,45 @@
+# Check password hook
+
+This hook allows you to externally check the provided password, its main use case is to allow to easily support things like password+OTP for protocols without keyboard interactive support such as FTP and WebDAV. You can ask your users to login using a string consisting of a fixed password and a One Time Token, you can verify the token inside the hook and ask to SFTPGo to verify the fixed part.
+
+The same thing can be achieved using [External authentication](./external-auth.md) but using this hook is simpler in some use cases.
+
+The `check password hook` can be defined as the absolute path of your program or an HTTP URL.
+
+The expected response is a JSON serialized struct containing the following keys:
+
+- `status` integer. 0 means KO, 1 means OK, 2 means partial success
+- `to_verify` string. For `status` = 2 SFTPGo will check this password against the one stored inside SFTPGo data provider
+
+If the hook defines an external program it can read the following environment variables:
+
+- `SFTPGO_AUTHD_USERNAME`
+- `SFTPGO_AUTHD_PASSWORD`
+- `SFTPGO_AUTHD_IP`
+- `SFTPGO_AUTHD_PROTOCOL`, possible values are `SSH`, `FTP`, `DAV`
+
+Previous global environment variables aren't cleared when the script is called. The content of these variables is _not_ quoted. They may contain special characters. They are under the control of a possibly malicious remote user.
+
+The program must write, on its standard output, the expected JSON serialized response described above.
+
+If the hook is an HTTP URL then it will be invoked as HTTP POST. The request body will contain a JSON serialized struct with the following fields:
+
+- `username`
+- `password`
+- `ip`
+- `protocol`, possible values are `SSH`, `FTP`, `DAV`
+
+If authentication succeeds the HTTP response code must be 200 and the response body must contain the expected JSON serialized response described above.
+
+The program hook must finish within 30 seconds, the HTTP hook timeout will use the global configuration for HTTP clients.
+
+You can also restrict the hook scope using the `check_password_scope` configuration key:
+
+- `0` means all supported protocols.
+- `1` means SSH only
+- `2` means FTP only
+- `4` means WebDAV only
+
+You can combine the scopes. For example, 6 means FTP and WebDAV.
+
+An example check password program allowing 2FA using password + one time token can be found inside the source tree [checkpwd](../examples/OTP/authy/checkpwd) directory.

docs/custom-actions.md

@@ -0,0 +1,89 @@
+# Custom Actions
+
+The `actions` struct inside the "common" configuration section allows to configure the actions for file operations and SSH commands.
+The `hook` can be defined as the absolute path of your program or an HTTP URL.
+
+The `upload` condition includes both uploads to new files and overwrite of existing files. If an upload is aborted for quota limits SFTPGo tries to remove the partial file, so if the notification reports a zero size file and a quota exceeded error the file has been deleted. The `ssh_cmd` condition will be triggered after a command is successfully executed via SSH. `scp` will trigger the `download` and `upload` conditions and not `ssh_cmd`.
+The notification will indicate if an error is detected and so, for example, a partial file is uploaded.
+The `pre-delete` action, if defined, will be called just before files deletion. If the external command completes with a zero exit status or the HTTP notification response code is `200` then SFTPGo will assume that the file was already deleted/moved and so it will not try to remove the file and it will not execute the hook defined for the `delete` action.
+
+If the `hook` defines a path to an external program, then this program is invoked with the following arguments:
+
+- `action`, string, possible values are: `download`, `upload`, `pre-delete`,`delete`, `rename`, `ssh_cmd`
+- `username`
+- `path` is the full filesystem path, can be empty for some ssh commands
+- `target_path`, non-empty for `rename` action and for `sftpgo-copy` SSH command
+- `ssh_cmd`, non-empty for `ssh_cmd` action
+
+The external program can also read the following environment variables:
+
+- `SFTPGO_ACTION`
+- `SFTPGO_ACTION_USERNAME`
+- `SFTPGO_ACTION_PATH`
+- `SFTPGO_ACTION_TARGET`, non-empty for `rename` `SFTPGO_ACTION`
+- `SFTPGO_ACTION_SSH_CMD`, non-empty for `ssh_cmd` `SFTPGO_ACTION`
+- `SFTPGO_ACTION_FILE_SIZE`, non-empty for `upload`, `download` and `delete` `SFTPGO_ACTION`
+- `SFTPGO_ACTION_FS_PROVIDER`, `0` for local filesystem, `1` for S3 backend, `2` for Google Cloud Storage (GCS) backend
+- `SFTPGO_ACTION_BUCKET`, non-empty for S3 and GCS backends
+- `SFTPGO_ACTION_ENDPOINT`, non-empty for S3 backend if configured
+- `SFTPGO_ACTION_STATUS`, integer. 0 means a generic error occurred. 1 means no error, 2 means quota exceeded error
+- `SFTPGO_ACTION_PROTOCOL`, string. Possible values are `SSH`, `SFTP`, `SCP`, `FTP`, `DAV`
+
+Previous global environment variables aren't cleared when the script is called.
+The program must finish within 30 seconds.
+
+If the `hook` defines an HTTP URL then this URL will be invoked as HTTP POST. The request body will contain a JSON serialized struct with the following fields:
+
+- `action`
+- `username`
+- `path`
+- `target_path`, not null for `rename` action
+- `ssh_cmd`, not null for `ssh_cmd` action
+- `file_size`, not null for `upload`, `download`, `delete` actions
+- `fs_provider`, `0` for local filesystem, `1` for S3 backend, `2` for Google Cloud Storage (GCS) backend
+- `bucket`, not null for S3 and GCS backends
+- `endpoint`, not null for S3 backend if configured
+- `status`, integer. 0 means a generic error occurred. 1 means no error, 2 means quota exceeded error
+- `protocol`, string. Possible values are `SSH`, `FTP`, `DAV`
+
+The HTTP request will use the global configuration for HTTP clients.
+
+The `actions` struct inside the "data_provider" configuration section allows you to configure actions on user add, update, delete.
+
+Actions will not be fired for internal updates, such as the last login or the user quota fields, or after external authentication.
+
+If the `hook` defines a path to an external program, then this program is invoked with the following arguments:
+
+- `action`, string, possible values are: `add`, `update`, `delete`
+- `username`
+- `ID`
+- `status`
+- `expiration_date`
+- `home_dir`
+- `uid`
+- `gid`
+
+The external program can also read the following environment variables:
+
+- `SFTPGO_USER_ACTION`
+- `SFTPGO_USER_USERNAME`
+- `SFTPGO_USER_PASSWORD`, hashed password as stored inside the data provider, can be empty if the user does not login using a password
+- `SFTPGO_USER_ID`
+- `SFTPGO_USER_STATUS`
+- `SFTPGO_USER_EXPIRATION_DATE`
+- `SFTPGO_USER_HOME_DIR`
+- `SFTPGO_USER_UID`
+- `SFTPGO_USER_GID`
+- `SFTPGO_USER_QUOTA_FILES`
+- `SFTPGO_USER_QUOTA_SIZE`
+- `SFTPGO_USER_UPLOAD_BANDWIDTH`
+- `SFTPGO_USER_DOWNLOAD_BANDWIDTH`
+- `SFTPGO_USER_MAX_SESSIONS`
+- `SFTPGO_USER_FS_PROVIDER`
+
+Previous global environment variables aren't cleared when the script is called.
+The program must finish within 15 seconds.
+
+If the `hook` defines an HTTP URL then this URL will be invoked as HTTP POST. The action is added to the query string, for example `<hook>?action=update`, and the user is sent serialized as JSON inside the POST body with sensitive fields removed.
+
+The HTTP request will use the global configuration for HTTP clients.

docs/dynamic-user-mod.md

@@ -0,0 +1,55 @@
+# Dynamic user creation or modification
+
+Dynamic user creation or modification is supported via an external program or an HTTP URL that can be invoked just before the user login.
+To enable dynamic user modification, you must set the absolute path of your program or an HTTP URL using the `pre_login_hook` key in your configuration file.
+
+The external program can read the following environment variables to get info about the user trying to login:
+
+- `SFTPGO_LOGIND_USER`, it contains the user trying to login serialized as JSON. A JSON serialized user id equal to zero means the user does not exist inside SFTPGo
+- `SFTPGO_LOGIND_METHOD`, possible values are: `password`, `publickey` and `keyboard-interactive`
+- `SFTPGO_LOGIND_IP`, ip address of the user trying to login
+- `SFTPGO_LOGIND_PROTOCOL`, possible values are `SSH`, `FTP`, `DAV`
+
+The program must write, on its standard output:
+
+- an empty string (or no response at all) if the user should not be created/updated
+- or the SFTPGo user, JSON serialized, if you want to create or update the given user
+
+If the hook is an HTTP URL then it will be invoked as HTTP POST. The login method, the used protocol and the ip address of the user trying to login are added to the query string, for example `<http_url>?login_method=password&ip=1.2.3.4&protocol=SSH`.
+The request body will contain the user trying to login serialized as JSON. If no modification is needed the HTTP response code must be 204, otherwise the response code must be 200 and the response body a valid SFTPGo user serialized as JSON.
+
+Actions defined for user's updates will not be executed in this case and an already logged in user with the same username will not be disconnected, you have to handle these things yourself.
+
+The JSON response can include only the fields to update instead of the full user. For example, if you want to disable the user, you can return a response like this:
+
+```json
+{"status": 0}
+```
+
+Please note that if you want to create a new user, the pre-login hook response must include all the mandatory user fields.
+
+The program hook must finish within 30 seconds, the HTTP hook will use the global configuration for HTTP clients.
+
+If an error happens while executing the hook then login will be denied.
+
+"Dynamic user creation or modification" and "External Authentication" are mutually exclusive, they are quite similar, the difference is that "External Authentication" returns an already authenticated user while using "Dynamic users modification" you simply create or update a user. The authentication will be checked inside SFTPGo.
+In other words while using "External Authentication" the external program receives the credentials of the user trying to login (for example the cleartext password) and it needs to validate them. While using "Dynamic users modification" the pre-login program receives the user stored inside the dataprovider (it includes the hashed password if any) and it can modify it, after the modification SFTPGo will check the credentials of the user trying to login.
+
+Let's see a very basic example. Our sample program will grant access to the existing user `test_user` only in the time range 10:00-18:00. Other users will not be modified since the program will terminate with no output.
+
+```shell
+#!/bin/bash
+
+CURRENT_TIME=`date +%H:%M`
+if [[ "$SFTPGO_LOGIND_USER" =~ "\"test_user\"" ]]
+then
+  if [[ $CURRENT_TIME > "18:00" || $CURRENT_TIME < "10:00" ]]
+  then
+    echo '{"status":0}'
+  else
+    echo '{"status":1}'
+  fi
+fi
+```
+
+Please note that this is a demo program and it might not work in all cases. For example, the username should be obtained by parsing the JSON serialized user and not by searching the username inside the JSON as shown here.

docs/external-auth.md

@@ -0,0 +1,58 @@
+# External Authentication
+
+To enable external authentication, you must set the absolute path of your authentication program or an HTTP URL using the `external_auth_hook` key in your configuration file.
+
+The external program can read the following environment variables to get info about the user trying to authenticate:
+
+- `SFTPGO_AUTHD_USERNAME`
+- `SFTPGO_AUTHD_IP`
+- `SFTPGO_AUTHD_PROTOCOL`, possible values are `SSH`, `FTP`, `DAV`
+- `SFTPGO_AUTHD_PASSWORD`, not empty for password authentication
+- `SFTPGO_AUTHD_PUBLIC_KEY`, not empty for public key authentication
+- `SFTPGO_AUTHD_KEYBOARD_INTERACTIVE`, not empty for keyboard interactive authentication
+
+Previous global environment variables aren't cleared when the script is called. The content of these variables is _not_ quoted. They may contain special characters. They are under the control of a possibly malicious remote user.
+The program must write, on its standard output, a valid SFTPGo user serialized as JSON if the authentication succeeds or a user with an empty username if the authentication fails.
+
+If the hook is an HTTP URL then it will be invoked as HTTP POST. The request body will contain a JSON serialized struct with the following fields:
+
+- `username`
+- `ip`
+- `protocol`, possible values are `SSH`, `FTP`, `DAV`
+- `password`, not empty for password authentication
+- `public_key`, not empty for public key authentication
+- `keyboard_interactive`, not empty for keyboard interactive authentication
+
+If authentication succeeds the HTTP response code must be 200 and the response body a valid SFTPGo user serialized as JSON. If the authentication fails the HTTP response code must be != 200 or the response body must be empty.
+
+If the authentication succeeds, the user will be automatically added/updated inside the defined data provider. Actions defined for users added/updated will not be executed in this case and an already logged in user with the same username will not be disconnected, you have to handle these things yourself.
+
+The program hook must finish within 30 seconds, the HTTP hook timeout will use the global configuration for HTTP clients.
+
+This method is slower than built-in authentication, but it's very flexible as anyone can easily write his own authentication hooks.
+You can also restrict the authentication scope for the hook using the `external_auth_scope` configuration key:
+
+- `0` means all supported authentication scopes. The external hook will be used for password, public key and keyboard interactive authentication
+- `1` means passwords only
+- `2` means public keys only
+- `4` means keyboard interactive only
+
+You can combine the scopes. For example, 3 means password and public key, 5 means password and keyboard interactive, and so on.
+
+Let's see a very basic example. Our sample authentication program will only accept user `test_user` with any password or public key.
+
+```shell
+#!/bin/sh
+
+if test "$SFTPGO_AUTHD_USERNAME" = "test_user"; then
+  echo '{"status":1,"username":"test_user","expiration_date":0,"home_dir":"/tmp/test_user","uid":0,"gid":0,"max_sessions":0,"quota_size":0,"quota_files":100000,"permissions":{"/":["*"],"/somedir":["list","download"]},"upload_bandwidth":0,"download_bandwidth":0,"filters":{"allowed_ip":[],"denied_ip":[]},"public_keys":[]}'
+else
+  echo '{"username":""}'
+fi
+```
+
+An example authentication program allowing to authenticate against an LDAP server can be found inside the source tree [ldapauth](../examples/ldapauth) directory.
+
+An example server, to use as HTTP authentication hook, allowing to authenticate against an LDAP server can be found inside the source tree [ldapauthserver](../examples/ldapauthserver) directory.
+
+If you have an external authentication hook that could be useful to others too, please let us know and/or please send a pull request.

docs/full-configuration.md

@@ -0,0 +1,197 @@
+# Configuring SFTPGo
+
+## Command line options
+
+The SFTPGo executable can be used this way:
+
+```console
+Usage:
+  sftpgo [command]
+
+Available Commands:
+  gen          A collection of useful generators
+  help         Help about any command
+  initprovider Initializes and/or updates the configured data provider
+  portable     Serve a single directory
+  serve        Start the SFTP Server
+
+Flags:
+  -h, --help      help for sftpgo
+  -v, --version
+
+ Use "sftpgo [command] --help" for more information about a command
+```
+
+The `serve` command supports the following flags:
+
+- `--config-dir` string. Location of the config dir. This directory should contain the configuration file and is used as the base directory for any files that use a relative path (eg. the private keys for the SFTP server, the SQLite or bblot database if you use SQLite or bbolt as data provider). The default value is "." or the value of `SFTPGO_CONFIG_DIR` environment variable.
+- `--config-file` string. Name of the configuration file. It must be the name of a file stored in `config-dir`, not the absolute path to the configuration file. The specified file name must have no extension because we automatically append JSON, YAML, TOML, HCL and Java extensions when we search for the file. The default value is "sftpgo" (and therefore `sftpgo.json`, `sftpgo.yaml` and so on are searched) or the value of `SFTPGO_CONFIG_FILE` environment variable.
+- `--log-compress` boolean. Determine if the rotated log files should be compressed using gzip. Default `false` or the value of `SFTPGO_LOG_COMPRESS` environment variable (1 or `true`, 0 or `false`). It is unused if `log-file-path` is empty.
+- `--log-file-path` string. Location for the log file, default "sftpgo.log" or the value of `SFTPGO_LOG_FILE_PATH` environment variable. Leave empty to write logs to the standard error.
+- `--log-max-age` int. Maximum number of days to retain old log files. Default 28 or the value of `SFTPGO_LOG_MAX_AGE` environment variable. It is unused if `log-file-path` is empty.
+- `--log-max-backups` int. Maximum number of old log files to retain. Default 5 or the value of `SFTPGO_LOG_MAX_BACKUPS` environment variable. It is unused if `log-file-path` is empty.
+- `--log-max-size` int. Maximum size in megabytes of the log file before it gets rotated. Default 10 or the value of `SFTPGO_LOG_MAX_SIZE` environment variable. It is unused if `log-file-path` is empty.
+- `--log-verbose` boolean. Enable verbose logs. Default `true` or the value of `SFTPGO_LOG_VERBOSE` environment variable (1 or `true`, 0 or `false`).
+
+Log file can be rotated on demand sending a `SIGUSR1` signal on Unix based systems and using the command `sftpgo service rotatelogs` on Windows.
+
+If you don't configure any private host key, the daemon will use `id_rsa` and `id_ecdsa` in the configuration directory. If these files don't exist, the daemon will attempt to autogenerate them (if the user that executes SFTPGo has write access to the `config-dir`). The server supports any private key format supported by [`crypto/ssh`](https://github.com/golang/crypto/blob/master/ssh/keys.go#L33).
+
+The `gen` command allows to generate completion scripts for your shell and man pages. Currently the man pages visual representation is wrong, take a look at this upstream [bug](https://github.com/spf13/cobra/issues/1049) for more details.
+
+## Configuration file
+
+The configuration file contains the following sections:
+
+- **"common"**, configuration parameters shared among all the supported protocols
+  - `idle_timeout`, integer. Time in minutes after which an idle client will be disconnected. 0 means disabled. Default: 15
+  - `upload_mode` integer. 0 means standard: the files are uploaded directly to the requested path. 1 means atomic: files are uploaded to a temporary path and renamed to the requested path when the client ends the upload. Atomic mode avoids problems such as a web server that serves partial files when the files are being uploaded. In atomic mode, if there is an upload error, the temporary file is deleted and so the requested upload path will not contain a partial file. 2 means atomic with resume support: same as atomic but if there is an upload error, the temporary file is renamed to the requested path and not deleted. This way, a client can reconnect and resume the upload.
+  - `actions`, struct. It contains the command to execute and/or the HTTP URL to notify and the trigger conditions. See [Custom Actions](./custom-actions.md) for more details
+    - `execute_on`, list of strings. Valid values are `download`, `upload`, `pre-delete`, `delete`, `rename`, `ssh_cmd`. Leave empty to disable actions.
+    - `hook`, string. Absolute path to the command to execute or HTTP URL to notify.
+  - `setstat_mode`, integer. 0 means "normal mode": requests for changing permissions, owner/group and access/modification times are executed. 1 means "ignore mode": requests for changing permissions, owner/group and access/modification times are silently ignored.
+  - `proxy_protocol`, integer. Support for [HAProxy PROXY protocol](https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt). If you are running SFTPGo behind a proxy server such as HAProxy, AWS ELB or NGNIX, you can enable the proxy protocol. It provides a convenient way to safely transport connection information such as a client's address across multiple layers of NAT or TCP proxies to get the real client IP address instead of the proxy IP. Both protocol versions 1 and 2 are supported. If the proxy protocol is enabled in SFTPGo then you have to enable the protocol in your proxy configuration too. For example, for HAProxy, add `send-proxy` or `send-proxy-v2` to each server configuration line. The following modes are supported:
+    - 0, disabled
+    - 1, enabled. Proxy header will be used and requests without proxy header will be accepted
+    - 2, required. Proxy header will be used and requests without proxy header will be rejected
+  - `proxy_allowed`, List of IP addresses and IP ranges allowed to send the proxy header:
+    - If `proxy_protocol` is set to 1 and we receive a proxy header from an IP that is not in the list then the connection will be accepted and the header will be ignored
+    - If `proxy_protocol` is set to 2 and we receive a proxy header from an IP that is not in the list then the connection will be rejected
+  - `post_connect_hook`, string. Absolute path to the command to execute or HTTP URL to notify. See [Post connect hook](./post-connect-hook.md) for more details. Leave empty to disable
+- **"sftpd"**, the configuration for the SFTP server
+  - `bind_port`, integer. The port used for serving SFTP requests. Default: 2022
+  - `bind_address`, string. Leave blank to listen on all available network interfaces. Default: ""
+  - `idle_timeout`, integer. Deprecated, please use the same key in `common` section.
+  - `max_auth_tries` integer. Maximum number of authentication attempts permitted per connection. If set to a negative number, the number of attempts is unlimited. If set to zero, the number of attempts is limited to 6.
+  - `banner`, string. Identification string used by the server. Leave empty to use the default banner. Default `SFTPGo_<version>`, for example `SSH-2.0-SFTPGo_0.9.5`
+  - `upload_mode` integer. Deprecated, please use the same key in `common` section.
+  - `actions`, struct. Deprecated, please use the same key in `common` section.
+  - `keys`, struct array. Deprecated, please use `host_keys`.
+    - `private_key`, path to the private key file. It can be a path relative to the config dir or an absolute one.
+  - `host_keys`, list of strings. It contains the daemon's private host keys. Each host key can be defined as a path relative to the configuration directory or an absolute one. If empty, the daemon will search or try to generate `id_rsa` and `id_ecdsa` keys inside the configuration directory. If you configure absolute paths to files named `id_rsa` and/or `id_ecdsa` then SFTPGo will try to generate these keys using the default settings.
+  - `kex_algorithms`, list of strings. Available KEX (Key Exchange) algorithms in preference order. Leave empty to use default values. The supported values can be found here: [`crypto/ssh`](https://github.com/golang/crypto/blob/master/ssh/common.go#L46 "Supported kex algos")
+  - `ciphers`, list of strings. Allowed ciphers. Leave empty to use default values. The supported values can be found here: [crypto/ssh](https://github.com/golang/crypto/blob/master/ssh/common.go#L28 "Supported ciphers")
+  - `macs`, list of strings. Available MAC (message authentication code) algorithms in preference order. Leave empty to use default values. The supported values can be found here: [crypto/ssh](https://github.com/golang/crypto/blob/master/ssh/common.go#L84 "Supported MACs")
+  - `trusted_user_ca_keys`, list of public keys paths of certificate authorities that are trusted to sign user certificates for authentication. The paths can be absolute or relative to the configuration directory.
+  - `login_banner_file`, path to the login banner file. The contents of the specified file, if any, are sent to the remote user before authentication is allowed. It can be a path relative to the config dir or an absolute one. Leave empty to disable login banner.
+  - `setstat_mode`, integer. Deprecated, please use the same key in `common` section.
+  - `enabled_ssh_commands`, list of enabled SSH commands. `*` enables all supported commands. More information can be found [here](./ssh-commands.md).
+  - `keyboard_interactive_auth_hook`, string. Absolute path to an external program or an HTTP URL to invoke for keyboard interactive authentication. See [Keyboard Interactive Authentication](./keyboard-interactive.md) for more details.
+  - `password_authentication`, boolean. Set to false to disable password authentication. This setting will disable multi-step authentication method using public key + password too. It is useful for public key only configurations if you need to manage old clients that will not attempt to authenticate with public keys if the password login method is advertised. Default: true.
+  - `proxy_protocol`, integer.  Deprecated, please use the same key in `common` section.
+  - `proxy_allowed`, list of strings. Deprecated, please use the same key in `common` section.
+- **"ftpd"**, the configuration for the FTP server
+  - `bind_port`, integer. The port used for serving FTP requests. 0 means disabled. Default: 0.
+  - `bind_address`, string. Leave blank to listen on all available network interfaces. Default: "".
+  - `banner`, string. Greeting banner displayed when a connection first comes in. Leave empty to use the default banner. Default `SFTPGo <version> ready`, for example `SFTPGo 1.0.0-dev ready`.
+  - `banner_file`, path to the banner file. The contents of the specified file, if any, are displayed when someone connects to the server. It can be a path relative to the config dir or an absolute one. If set, it overrides the banner string provided by the `banner` option. Leave empty to disable.
+  - `active_transfers_port_non_20`, boolean. Do not impose the port 20 for active data transfers. Enabling this option allows to run SFTPGo with less privilege. Default: false.
+  - `force_passive_ip`, ip address. External IP address to expose for passive connections. Leavy empty to autodetect. Defaut: "".
+  - `passive_port_range`, struct containing the key `start` and `end`. Port Range for data connections. Random if not specified. Default range is 50000-50100.
+  - `certificate_file`, string. Certificate for FTPS. This can be an absolute path or a path relative to the config dir.
+  - `certificate_key_file`, string. Private key matching the above certificate. This can be an absolute path or a path relative to the config dir. If both the certificate and the private key are provided the server will accept both plain FTP an explicit FTP over TLS. Certificate and key files can be reloaded on demand sending a `SIGHUP` signal on Unix based systems and a `paramchange` request to the running service on Windows.
+  - `tls_mode`, integer. 0 means accept both cleartext and encrypted sessions. 1 means TLS is required for both control and data connection. Do not enable this blindly, please check that a proper TLS config is in place or no login will be allowed if `tls_mode` is 1.
+- **webdavd**, the configuration for the WebDAV server, more info [here](./webdav.md)
+  - `bind_port`, integer. The port used for serving WebDAV requests. 0 means disabled. Default: 0.
+  - `bind_address`, string. Leave blank to listen on all available network interfaces. Default: "".
+  - `certificate_file`, string. Certificate for WebDAV over HTTPS. This can be an absolute path or a path relative to the config dir.
+  - `certificate_key_file`, string. Private key matching the above certificate. This can be an absolute path or a path relative to the config dir. If both the certificate and the private key are provided the server will expect HTTPS connections. Certificate and key files can be reloaded on demand sending a `SIGHUP` signal on Unix based systems and a `paramchange` request to the running service on Windows.
+  - `cors` struct containing CORS configuration. SFTPGo uses [Go CORS handler](https://github.com/rs/cors), please refer to upstream documentation for fields meaning and their default values.
+    - `enabled`, boolean, set to true to enable CORS.
+    - `allowed_origins`, list of strings.
+    - `allowed_methods`, list of strings.
+    - `allowed_headers`, list of strings.
+    - `exposed_headers`, list of strings.
+    - `allow_credentials` boolean.
+    - `max_age`, integer.
+  - `cache` struct containing cache configuration for the authenticated users.
+    - `enabled`, boolean, set to true to enable user caching. Default: true.
+    - `expiration_time`, integer. Expiration time, in minutes, for the cached users. 0 means unlimited. Default: 0.
+    - `max_size`, integer. Maximum number of users to cache. 0 means unlimited. Default: 50.
+- **"data_provider"**, the configuration for the data provider
+  - `driver`, string. Supported drivers are `sqlite`, `mysql`, `postgresql`, `bolt`, `memory`
+  - `name`, string. Database name. For driver `sqlite` this can be the database name relative to the config dir or the absolute path to the SQLite database. For driver `memory` this is the (optional) path relative to the config dir or the absolute path to the users dump, obtained using the `dumpdata` REST API, to load. This dump will be loaded at startup and can be reloaded on demand sending a `SIGHUP` signal on Unix based systems and a `paramchange` request to the running service on Windows. The `memory` provider will not modify the provided file so quota usage and last login will not be persisted
+  - `host`, string. Database host. Leave empty for drivers `sqlite`, `bolt` and `memory`
+  - `port`, integer. Database port. Leave empty for drivers `sqlite`, `bolt` and `memory`
+  - `username`, string. Database user. Leave empty for drivers `sqlite`, `bolt` and `memory`
+  - `password`, string. Database password. Leave empty for drivers `sqlite`, `bolt` and `memory`
+  - `sslmode`, integer. Used for drivers `mysql` and `postgresql`. 0 disable SSL/TLS connections, 1 require ssl, 2 set ssl mode to `verify-ca` for driver `postgresql` and `skip-verify` for driver `mysql`, 3 set ssl mode to `verify-full` for driver `postgresql` and `preferred` for driver `mysql`
+  - `connectionstring`, string. Provide a custom database connection string. If not empty, this connection string will be used instead of building one using the previous parameters. Leave empty for drivers `bolt` and `memory`
+  - `sql_tables_prefix`, string. Prefix for SQL tables
+  - `manage_users`, integer. Set to 0 to disable users management, 1 to enable
+  - `track_quota`, integer. Set the preferred mode to track users quota between the following choices:
+    - 0, disable quota tracking. REST API to scan users home directories/virtual folders and update quota will do nothing
+    - 1, quota is updated each time a user uploads or deletes a file, even if the user has no quota restrictions
+    - 2, quota is updated each time a user uploads or deletes a file, but only for users with quota restrictions and for virtual folders. With this configuration, the `quota scan` and `folder_quota_scan` REST API can still be used to periodically update space usage for users without quota restrictions and for folders
+  - `pool_size`, integer. Sets the maximum number of open connections for `mysql` and `postgresql` driver. Default 0 (unlimited)
+  - `users_base_dir`, string. Users default base directory. If no home dir is defined while adding a new user, and this value is a valid absolute path, then the user home dir will be automatically defined as the path obtained joining the base dir and the username
+  - `actions`, struct. It contains the command to execute and/or the HTTP URL to notify and the trigger conditions. See [Custom Actions](./custom-actions.md) for more details
+    - `execute_on`, list of strings. Valid values are `add`, `update`, `delete`. `update` action will not be fired for internal updates such as the last login or the user quota fields.
+    - `hook`, string. Absolute path to the command to execute or HTTP URL to notify.
+  - `external_auth_program`, string. Deprecated, please use `external_auth_hook`.
+  - `external_auth_hook`, string. Absolute path to an external program or an HTTP URL to invoke for users authentication. See [External Authentication](./external-auth.md) for more details. Leave empty to disable.
+  - `external_auth_scope`, integer. 0 means all supported authentication scopes (passwords, public keys and keyboard interactive). 1 means passwords only. 2 means public keys only. 4 means key keyboard interactive only. The flags can be combined, for example 6 means public keys and keyboard interactive
+  - `credentials_path`, string. It defines the directory for storing user provided credential files such as Google Cloud Storage credentials. This can be an absolute path or a path relative to the config dir
+  - `pre_login_program`, string. Deprecated, please use `pre_login_hook`.
+  - `pre_login_hook`, string. Absolute path to an external program or an HTTP URL to invoke to modify user details just before the login. See [Dynamic user modification](./dynamic-user-mod.md) for more details. Leave empty to disable.
+  - `post_login_hook`, string. Absolute path to an external program or an HTTP URL to invoke to notify a successful or failed login. See [Post-login hook](./post-login-hook.md) for more details. Leave empty to disable.
+  - `post_login_scope`, defines the scope for the post-login hook. 0 means notify both failed and successful logins. 1 means notify failed logins. 2 means notify successful logins.
+  - `check_password_hook`, string.  Absolute path to an external program or an HTTP URL to invoke to check the user provided password. See [Check password hook](./check-password-hook.md) for more details. Leave empty to disable.
+  - `check_password_scope`, defines the scope for the check password hook. 0 means all protocols, 1 means SSH, 2 means FTP, 4 means WebDAV. You can combine the scopes, for example 6 means FTP and WebDAV.
+  - `password_hashing`, struct. It contains the configuration parameters to be used to generate the password hash. SFTPGo can verify passwords in several formats and uses the `argon2id` algorithm to hash passwords in plain-text before storing them inside the data provider. These options allow you to customize how the hash is generated.
+    - `argon2_options` struct containing the options for argon2id hashing algorithm. The `memory` and `iterations` parameters control the computational cost of hashing the password. The higher these figures are, the greater the cost of generating the hash and the longer the runtime. It also follows that the greater the cost will be for any attacker trying to guess the password. If the code is running on a machine with multiple cores, then you can decrease the runtime without reducing the cost by increasing the `parallelism` parameter. This controls the number of threads that the work is spread across.
+      - `memory`, unsigned integer. The amount of memory used by the algorithm (in kibibytes). Default: 65536.
+      - `iterations`, unsigned integer. The number of iterations over the memory. Default: 1.
+      - `parallelism`. unsigned 8 bit integer. The number of threads (or lanes) used by the algorithm. Default: 2.
+  - `update_mode`, integer. Defines how the database will be initialized/updated. 0 means automatically. 1 means manually using the initprovider sub-command.
+- **"httpd"**, the configuration for the HTTP server used to serve REST API and to expose the built-in web interface
+  - `bind_port`, integer. The port used for serving HTTP requests. Set to 0 to disable HTTP server. Default: 8080
+  - `bind_address`, string. Leave blank to listen on all available network interfaces. Default: "127.0.0.1"
+  - `templates_path`, string. Path to the HTML web templates. This can be an absolute path or a path relative to the config dir
+  - `static_files_path`, string. Path to the static files for the web interface. This can be an absolute path or a path relative to the config dir. If both `templates_path` and `static_files_path` are empty the built-in web interface will be disabled
+  - `backups_path`, string. Path to the backup directory. This can be an absolute path or a path relative to the config dir. We don't allow backups in arbitrary paths for security reasons
+  - `auth_user_file`, string. Path to a file used to store usernames and passwords for basic authentication. This can be an absolute path or a path relative to the config dir. We support HTTP basic authentication, and the file format must conform to the one generated using the Apache `htpasswd` tool. The supported password formats are bcrypt (`$2y$` prefix) and md5 crypt (`$apr1$` prefix). If empty, HTTP authentication is disabled.
+  - `certificate_file`, string. Certificate for HTTPS. This can be an absolute path or a path relative to the config dir.
+  - `certificate_key_file`, string. Private key matching the above certificate. This can be an absolute path or a path relative to the config dir. If both the certificate and the private key are provided, the server will expect HTTPS connections. Certificate and key files can be reloaded on demand sending a `SIGHUP` signal on Unix based systems and a `paramchange` request to the running service on Windows.
+- **"http"**, the configuration for HTTP clients. HTTP clients are used for executing hooks such as the ones used for custom actions, external authentication and pre-login user modifications
+  - `timeout`, integer. Timeout specifies a time limit, in seconds, for requests.
+  - `ca_certificates`, list of strings. List of paths to extra CA certificates to trust. The paths can be absolute or relative to the config dir. Adding trusted CA certificates is a convenient way to use self-signed certificates without defeating the purpose of using TLS.
+  - `skip_tls_verify`, boolean. if enabled the HTTP client accepts any TLS certificate presented by the server and any host name in that certificate. In this mode, TLS is susceptible to man-in-the-middle attacks. This should be used only for testing.
+
+A full example showing the default config (in JSON format) can be found [here](../sftpgo.json).
+
+If you want to use a private host key that uses an algorithm/setting different from the auto generated RSA/ECDSA keys, or more than two private keys, you can generate your own keys and replace the empty `keys` array with something like this:
+
+```json
+"host_keys": [
+  "id_rsa",
+  "id_ecdsa",
+  "id_ed25519"
+]
+```
+
+where `id_rsa`, `id_ecdsa` and `id_ed25519`, in this example, are files containing your generated keys. You can use absolute paths or paths relative to the configuration directory.
+
+If you want the default host keys generation in a directory different from the config dir, please specify absolute paths to files named `id_rsa` or `id_ecdsa` like this:
+
+```json
+"host_keys": [
+  "/etc/sftpgo/keys/id_rsa",
+  "/etc/sftpgo/keys/id_ecdsa"
+]
+```
+
+then SFTPGo will try to create `id_rsa` and `id_ecdsa`, if they are missing, inside the existing directory `/etc/sftpgo/keys`.
+
+The configuration can be read from JSON, TOML, YAML, HCL, envfile and Java properties config files. If your `config-file` flag is set to `sftpgo` (default value), you need to create a configuration file called `sftpgo.json` or `sftpgo.yaml` and so on inside `config-dir`.
+
+## Environment variables
+
+You can also override all the available configuration options using environment variables. SFTPGo will check for environment variables with a name matching the key uppercased and prefixed with the `SFTPGO_`. You need to use `__` to traverse a struct.
+
+Let's see some examples:
+
+- To set sftpd `bind_port`, you need to define the env var `SFTPGO_SFTPD__BIND_PORT`
+- To set the `execute_on` actions, you need to define the env var `SFTPGO_COMMON__ACTIONS__EXECUTE_ON`. For example `SFTPGO_COMMON__ACTIONS__EXECUTE_ON=upload,download`
+
+Please note that in order to override configuration options with environment variables, you need a configuration file containing the options to override, this is a [viper bug](https://github.com/spf13/viper/issues/584). For example, you can deploy the default configuration file and then override the options to customize using environment variables.

docs/google-cloud-storage.md

@@ -0,0 +1,13 @@
+# Google Cloud Storage backend
+
+To connect SFTPGo to Google Cloud Storage you can use use the Application Default Credentials (ADC) strategy to try to find your application's credentials automatically or you can explicitly provide a JSON credentials file that you can obtain from the Google Cloud Console. Take a look [here](https://cloud.google.com/docs/authentication/production#providing_credentials_to_your_application) for details.
+
+Specifying a different `key_prefix`, you can assign different "folders" of the same bucket to different users. This is similar to a chroot directory for local filesystem. Each SFTP/SCP user can only access the assigned folder and its contents. The folder identified by `key_prefix` does not need to be pre-created.
+
+You can optionally specify a [storage class](https://cloud.google.com/storage/docs/storage-classes) too. Leave it blank to use the default storage class.
+
+The configured bucket must exist.
+
+Google Cloud Storage is exposed over HTTPS so if you are running SFTPGo as docker image please be sure to uncomment the line that installs `ca-certificates`, inside your `Dockerfile`, to be able to properly verify certificate authorities.
+
+This backend is very similar to the [S3](./s3.md) backend, and it has the same limitations.

docs/howto/README.md

@@ -0,0 +1,6 @@
+# Tutorials
+
+Here we collect step-to-step tutorials. SFTPGo users are encouraged to contribute!
+
+- [SFTPGo with PostgreSQL data provider and S3 backend](./postgresql-s3.md)
+- [Expose Web Admin and REST API over HTTPS and password protected](./rest-api-https-auth.md)

docs/howto/postgresql-s3.md

@@ -0,0 +1,215 @@
+# SFTPGo with PostgreSQL data provider and S3 backend
+
+This tutorial shows the installation of SFTPGo on Ubuntu 20.04 (Focal Fossa) with PostgreSQL data provider and S3 backend. SFTPGo will run as an unprivileged (non-root) user. We assume that you want to serve a single S3 bucket and you want to assign different "virtual folders" of this bucket to different SFTPGo virtual users.
+
+## Preliminary Note
+
+Before proceeding further you need to have a basic minimal installation of Ubuntu 20.04.
+
+## Install PostgreSQL
+
+Before installing any packages on the Ubuntu system, update and upgrade all packages using the `apt` commands below.
+
+```shell
+sudo apt update
+sudo apt upgrade
+```
+
+Install PostgreSQL with this `apt` command.
+
+```shell
+sudo apt -y install postgresql
+```
+
+Once installation is completed, start the PostgreSQL service and add it to the system boot.
+
+```shell
+sudo systemctl start postgresql
+sudo systemctl enable postgresql
+```
+
+Next, check the PostgreSQL service using the following command.
+
+```shell
+systemctl status postgresql
+```
+
+## Configure PostgreSQL
+
+PostgreSQL uses roles for user authentication and authorization, it just like Unix-Style permissions. By default, PostgreSQL creates a new user called `postgres` for basic authentication.
+
+In this step, we will create a new PostgreSQL user for SFTPGo.
+
+Login to the PostgreSQL shell using the command below.
+
+```shell
+sudo -i -u postgres psql
+```
+
+Next, create a new role `sftpgo` with the password `sftpgo_pg_pwd` using the following query.
+
+```sql
+create user "sftpgo" with encrypted password 'sftpgo_pg_pwd';
+```
+
+Next, create a new database `sftpgo.db` for the SFTPGo service using the following queries.
+
+```sql
+create database "sftpgo.db";
+grant all privileges on database "sftpgo.db" to "sftpgo";
+```
+
+Exit from the PostgreSQL shell typing `\q`.
+
+## Install SFTPGo
+
+To install SFTPGo you can use the PPA [here](https://launchpad.net/~sftpgo/+archive/ubuntu/sftpgo).
+
+Start by adding the PPA.
+
+```shell
+sudo add-apt-repository ppa:sftpgo/sftpgo
+sudo apt-get update
+```
+
+Next install SFTPGo.
+
+```shell
+sudo apt install sftpgo
+```
+
+After installation SFTPGo should already be running with default configuration and configured to start automatically at boot, check its status using the following command.
+
+```shell
+systemctl status sftpgo
+```
+
+## Configure AWS credentials
+
+We assume that you want to serve a single S3 bucket and you want to assign different "virtual folders" of this bucket to different SFTPGo virtual users. In this case is very convenient to configure a credential file so SFTPGo will automatically use it and you don't need to specify the same AWS credentials for each user.
+
+You can manually create the `/var/lib/sftpgo/.aws/credentials` file and write your AWS credentials like this.
+
+```shell
+[default]
+aws_access_key_id=AKIAIOSFODNN7EXAMPLE
+aws_secret_access_key=wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY
+```
+
+Alternately you can install `AWS CLI` and manage the credential using this tool.
+
+```shell
+sudo apt install awscli
+```
+
+and now set your credentials, region, and output format with the following command.
+
+```shell
+aws configure
+```
+
+Confirm that you can list your bucket contents with the following command.
+
+```shell
+aws s3 ls s3://mybucket
+```
+
+The AWS CLI will create the credential file in `~/.aws/credentials`. The SFTPGo service runs using the `sftpgo` system user whose home directory is `/var/lib/sftpgo` so you need to copy the credentials file to the sftpgo home directory and assign it the proper permissions.
+
+```shell
+sudo mkdir /var/lib/sftpgo/.aws
+sudo cp ~/.aws/credentials /var/lib/sftpgo/.aws/
+sudo chown -R sftpgo:sftpgo /var/lib/sftpgo/.aws
+```
+
+## Configure SFTPGo
+
+Now open the SFTPGo configuration.
+
+```shell
+sudo vi /etc/sftpgo/sftpgo.json
+```
+
+Search for the `data_provider` section and change it as follow.
+
+```json
+  "data_provider": {
+    "driver": "postgresql",
+    "name": "sftpgo.db",
+    "host": "127.0.0.1",
+    "port": 5432,
+    "username": "sftpgo",
+    "password": "sftpgo_pg_pwd",
+    ...
+}
+```
+
+This way we set the PostgreSQL connection parameters and a default base directory for new users.
+
+If you want to connect to PostgreSQL over a Unix Domain socket you have to set the value `/var/run/postgresql` for the `host` configuration key instead of `127.0.0.1`.
+
+You can further customize your configuration adding custom actions and other hooks. A full explanation of all configuration parameters can be found [here](../full-configuration.md).
+
+Next, initialize the data provider with the following command.
+
+```shell
+$ sudo su - sftpgo -s /bin/bash -c 'sftpgo initprovider -c /etc/sftpgo'
+2020-10-09T21:07:50.000 INF Initializing provider: "postgresql" config file: "/etc/sftpgo/sftpgo.json"
+2020-10-09T21:07:50.000 INF updating database version: 1 -> 2
+2020-10-09T21:07:50.000 INF updating database version: 2 -> 3
+2020-10-09T21:07:50.000 INF updating database version: 3 -> 4
+2020-10-09T21:07:50.000 INF Data provider successfully initialized/updated
+```
+
+The default sftpgo systemd service will start after the network target, in this setup it is more appropriate to start it after the PostgreSQL service, so edit the service using the following command.
+
+```shell
+sudo systemctl edit sftpgo.service
+```
+
+And override the unit definition with the following snippet.
+
+```shell
+[Unit]
+After=postgresql.service
+```
+
+Confirm that `sftpgo.service` will start after `postgresql.service` with the next command.
+
+```shell
+$ systemctl show sftpgo.service | grep After=
+After=postgresql.service systemd-journald.socket system.slice -.mount systemd-tmpfiles-setup.service network.target sysinit.target basic.target
+```
+
+Next restart the sftpgo service to use the new configuration and check that it is running.
+
+```shell
+sudo systemctl restart sftpgo
+systemctl status sftpgo
+```
+
+## Add virtual users
+
+The easiest way to add virtual users is to use the built-in Web interface.
+
+You can expose the Web Admin interface over the network replacing `"bind_address": "127.0.0.1"` in the `httpd` configuration section with `"bind_address": ""` and apply the change restarting the SFTPGo service with the following command.
+
+```shell
+sudo systemctl restart sftpgo
+```
+
+So now open the Web Admin URL.
+
+[http://127.0.0.1:8080/web](http://127.0.0.1:8080/web)
+
+Click `Add` and fill the user details, the minimum required parameters are:
+
+- `Username`
+- `Password` or `Public keys`
+- `Permissions`
+- `Home Dir` can be empty since we defined a default base dir
+- Select `Amazon S3 (Compatible)` as storage and then set `Bucket`, `Region` and optionally a `Key Prefix` if you want to restrict the user to a specific virtual folder in the bucket. The specified virtual folder does not need to be pre-created. You can leave `Access Key` and `Access Secret` empty since we defined global credentials for the `sftpgo` user and we use this system user to run the SFTPGo service.
+
+You are done! Now you can connect to you SFTPGo instance using any compatible `sftp` client on port `2022`.
+
+You can mix S3 users with local users but please be aware that we are running the service as the unprivileged `sftpgo` system user so if you set storage as `local` for an SFTPGo virtual user then the home directory for this user must be owned by the `sftpgo` system user. If you don't specify an home directory the default will be `/var/lib/sftpgo/users/<username>` which should be appropriate.

docs/howto/rest-api-https-auth.md

@@ -0,0 +1,122 @@
+# Expose Web Admin and REST API over HTTPS and password protected
+
+This tutorial shows how to expose the SFTPGo web interface and REST API over HTTPS and password protect them.
+
+## Preliminary Note
+
+Before proceeding further you need to have a SFTPGo instance already configured and running.
+
+We assume:
+
+- you are running SFTPGo as service using the dedicated `sftpgo` system user
+- the SFTPGo configuration directory is `/etc/sftpgo`
+- you are running SFTPGo on Ubuntu 20.04, however this instructions can be easily adapted for other Linux variants.
+
+## Authentication Setup
+
+First install the `htpasswd` tool. We use this tool to create the users for the Web Admin/REST API.
+
+```shell
+sudo apt install apache2-utils
+```
+
+Create a user for web based authentication.
+
+```shell
+sudo htpasswd -B -c /etc/sftpgo/httpauth sftpgoweb
+```
+
+If you want to create additional users omit the `-c` option.
+
+```shell
+sudo htpasswd -B /etc/sftpgo/httpauth anotheruser
+```
+
+Next open the SFTPGo configuration.
+
+```shell
+sudo vi /etc/sftpgo/sftpgo.json
+```
+
+Search for the `httpd` section and change it as follow.
+
+```json
+  "httpd": {
+    "bind_port": 8080,
+    "bind_address": "",
+    "templates_path": "templates",
+    "static_files_path": "static",
+    "backups_path": "backups",
+    "auth_user_file": "/etc/sftpgo/httpauth",
+    "certificate_file": "",
+    "certificate_key_file": ""
+  }
+```
+
+Setting an empty `bind_address` means that the service will listen on all available network interfaces and so it will be exposed over the network.
+
+Now restart the SFTPGo service to apply the changes.
+
+```shell
+sudo systemctl restart sftpgo
+```
+
+You are done! Now login to the Web Admin interface using the username and password created above.
+
+## Creation of a Self-Signed Certificate
+
+For demostration purpose we use a self-signed certificate here. These certificates are easy to make and do not cost money. However, they do not provide all of the security properties that certificates signed by a Public Certificate Authority (CA) aim to provide, you are encouraged to use a certificate signed by a Public CA.
+
+When creating a new SSL certificate, one needs to specify the duration validity of the same by changing the value 365 (as appearing in the message below) to the preferred number of days. It is important to mention here that the certificate so created stands to auto-expire upon completion of one year.
+
+```shell
+sudo mkdir /etc/sftpgo/ssl
+sudo openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout /etc/sftpgo/ssl/sftpgo.key -out /etc/sftpgo/ssl/sftpgo.crt
+```
+
+The above command is rather versatile, and lets you create both the self-signed SSL certificate and the server key to safeguard it, in addition to placing both of these into the `etc/sftpgo/ssl` directory. Answer to the questions to create the certificate and the key for HTTPS.
+
+Assign the proper permissions to the generated certificates.
+
+```shell
+sudo chown -R sftpgo:sftpgo /etc/sftpgo/ssl
+```
+
+## HTTPS Setup
+
+Open the SFTPGo configuration.
+
+```shell
+sudo vi /etc/sftpgo/sftpgo.json
+```
+
+Search for the `httpd` section and change it as follow.
+
+```json
+  "httpd": {
+    "bind_port": 8080,
+    "bind_address": "",
+    "templates_path": "templates",
+    "static_files_path": "static",
+    "backups_path": "backups",
+    "auth_user_file": "/etc/sftpgo/httpauth",
+    "certificate_file": "/etc/sftpgo/ssl/sftpgo.crt",
+    "certificate_key_file": "/etc/sftpgo/ssl/sftpgo.key"
+  }
+```
+
+Now restart the SFTPGo service to apply the changes.
+
+```shell
+sudo systemctl restart sftpgo
+```
+
+You are done! Now SFTPGo web admin and REST API are exposed over HTTPS and password protected.
+
+You can easily replace the self-signed certificate used here with a properly signed certificate.
+
+The certificate could frequently change if you use something like [let's encrypt](https://letsencrypt.org/). SFTPGo allows hot-certificate reloading using the following command.
+
+```shell
+sudo systemctl reload sftpgo
+```

docs/keyboard-interactive.md

@@ -0,0 +1,168 @@
+# Keyboard Interactive Authentication
+
+Keyboard interactive authentication is, in general, a series of questions asked by the server with responses provided by the client.
+This authentication method is typically used for multi-factor authentication.
+There are no restrictions on the number of questions asked on a particular authentication stage; there are also no restrictions on the number of stages involving different sets of questions.
+
+To enable keyboard interactive authentication, you must set the absolute path of your authentication program or an HTTP URL using the  `keyboard_interactive_auth_hook` key in your configuration file.
+
+The external program can read the following environment variables to get info about the user trying to authenticate:
+
+- `SFTPGO_AUTHD_USERNAME`
+- `SFTPGO_AUTHD_IP`
+- `SFTPGO_AUTHD_PASSWORD`, this is the hashed password as stored inside the data provider
+
+Previous global environment variables aren't cleared when the script is called. The content of these variables is _not_ quoted. They may contain special characters.
+
+The program must write the questions on its standard output, in a single line, using the following struct JSON serialized:
+
+- `instruction`, string. A short description to show to the user that is trying to authenticate. Can be empty or omitted
+- `questions`, list of questions to be asked to the user
+- `echos` list of boolean flags corresponding to the questions (so the lengths of both lists must be the same) and indicating whether user's reply for a particular question should be echoed on the screen while they are typing: true if it should be echoed, or false if it should be hidden.
+- `check_password` optional integer. Ask exactly one question and set this field to 1 if the expected answer is the user password and you want that SFTPGo checks it for you. If the password is correct, the returned response to the program is `OK`. If the password is wrong, the program will be terminated and an authentication error will be returned to the user that is trying to authenticate.
+- `auth_result`, integer. Set this field to 1 to indicate successful authentication. 0 is ignored. Any other value means authentication error. If this field is found and it is different from 0 then SFTPGo will not read any other questions from the external program, and it will finalize the authentication.
+
+SFTPGo writes the user answers to the program standard input, one per line, in the same order as the questions.
+Please be sure that your program receives the answers for all the issued questions before asking for the next ones.
+
+Keyboard interactive authentication can be chained to the external authentication.
+The authentication must finish within 60 seconds.
+
+Let's see a very basic example. Our sample keyboard interactive authentication program will ask for 2 sets of questions and accept the user if the answer to the last question is `answer3`.
+
+```shell
+#!/bin/sh
+
+echo '{"questions":["Question1: ","Question2: "],"instruction":"This is a sample for keyboard interactive authentication","echos":[true,false]}'
+
+read ANSWER1
+read ANSWER2
+
+echo '{"questions":["Question3: "],"instruction":"","echos":[true]}'
+
+read ANSWER3
+
+if test "$ANSWER3" = "answer3"; then
+  echo '{"auth_result":1}'
+else
+  echo '{"auth_result":-1}'
+fi
+```
+
+and here is an example where SFTPGo checks the user password for you:
+
+```shell
+#!/bin/sh
+
+echo '{"questions":["Password: "],"instruction":"This is a sample for keyboard interactive authentication","echos":[false],"check_password":1}'
+
+read ANSWER1
+
+if test "$ANSWER1" != "OK"; then
+  exit 1
+fi
+
+echo '{"questions":["One time token: "],"instruction":"","echos":[false]}'
+
+read ANSWER2
+
+if test "$ANSWER2" = "token"; then
+  echo '{"auth_result":1}'
+else
+  echo '{"auth_result":-1}'
+fi
+```
+
+If the hook is an HTTP URL then it will be invoked as HTTP POST multiple times for each login request.
+The request body will contain a JSON struct with the following fields:
+
+- `request_id`, string. Unique request identifier
+- `username`, string
+- `ip`, string
+- `password`, string. This is the hashed password as stored inside the data provider
+- `answers`, list of string. It will be null for the first request
+- `questions`, list of string. It will contain the previously asked questions. It will be null for the first request
+
+The HTTP response code must be 200 and the body must contain the same JSON struct described for the program.
+
+Let's see a basic sample, the configured hook is `http://127.0.0.1:8000/keyIntHookPwd`, as soon as the user tries to login, SFTPGo makes this HTTP POST request:
+
+```shell
+POST /keyIntHookPwd HTTP/1.1
+Host: 127.0.0.1:8000
+User-Agent: Go-http-client/1.1
+Content-Length: 189
+Content-Type: application/json
+Accept-Encoding: gzip
+
+{"request_id":"bq1r5r7cdrpd2qtn25ng","username":"a","ip":"127.0.0.1","password":"$pbkdf2-sha512$150000$ClOPkLNujMTL$XktKy0xuJsOfMYBz+f2bIyPTdbvDTSnJ1q+7+zp/HPq5Qojwp6kcpSIiVHiwvbi8P6HFXI/D3UJv9BLcnQFqPA=="}
+```
+
+as you can see in this first requests `answers` and `questions` are null.
+
+Here is the response that instructs SFTPGo to ask for the user password and to check it:
+
+```shell
+HTTP/1.1 200 OK
+Date: Tue, 31 Mar 2020 21:15:24 GMT
+Server: WSGIServer/0.2 CPython/3.8.2
+Content-Type: application/json
+X-Frame-Options: SAMEORIGIN
+Content-Length: 143
+
+{"questions": ["Password: "], "check_password": 1, "instruction": "This is a sample for keyboard interactive authentication", "echos": [false]}
+```
+
+The user enters the correct password and so SFTPGo makes a new HTTP POST, please note that the `request_id` is the same of the previous request, this time the asked `questions` and the user's `answers` are not null:
+
+```shell
+POST /keyIntHookPwd HTTP/1.1
+Host: 127.0.0.1:8000
+User-Agent: Go-http-client/1.1
+Content-Length: 233
+Content-Type: application/json
+Accept-Encoding: gzip
+
+{"request_id":"bq1r5r7cdrpd2qtn25ng","username":"a","ip":"127.0.0.1","password":"$pbkdf2-sha512$150000$ClOPkLNujMTL$XktKy0xuJsOfMYBz+f2bIyPTdbvDTSnJ1q+7+zp/HPq5Qojwp6kcpSIiVHiwvbi8P6HFXI/D3UJv9BLcnQFqPA==","answers":["OK"],"questions":["Password: "]}
+```
+
+Here is the HTTP response that instructs SFTPGo to ask for a new question:
+
+```shell
+HTTP/1.1 200 OK
+Date: Tue, 31 Mar 2020 21:15:27 GMT
+Server: WSGIServer/0.2 CPython/3.8.2
+Content-Type: application/json
+X-Frame-Options: SAMEORIGIN
+Content-Length: 66
+
+{"questions": ["Question2: "], "instruction": "", "echos": [true]}
+```
+
+As soon as the user answer to this question, SFTPGo will make a new HTTP POST request with the user's answers:
+
+```shell
+POST /keyIntHookPwd HTTP/1.1
+Host: 127.0.0.1:8000
+User-Agent: Go-http-client/1.1
+Content-Length: 239
+Content-Type: application/json
+Accept-Encoding: gzip
+
+{"request_id":"bq1r5r7cdrpd2qtn25ng","username":"a","ip":"127.0.0.1","password":"$pbkdf2-sha512$150000$ClOPkLNujMTL$XktKy0xuJsOfMYBz+f2bIyPTdbvDTSnJ1q+7+zp/HPq5Qojwp6kcpSIiVHiwvbi8P6HFXI/D3UJv9BLcnQFqPA==","answers":["answer2"],"questions":["Question2: "]}
+```
+
+Here is the final HTTP response that allows the user login:
+
+```shell
+HTTP/1.1 200 OK
+Date: Tue, 31 Mar 2020 21:15:29 GMT
+Server: WSGIServer/0.2 CPython/3.8.2
+Content-Type: application/json
+X-Frame-Options: SAMEORIGIN
+Content-Length: 18
+
+{"auth_result": 1}
+```
+
+An example keyboard interactive program allowing to authenticate using [Twilio Authy 2FA](https://www.twilio.com/docs/authy) can be found inside the source tree [authy](../examples/OTP/authy) directory.

docs/logs.md

@@ -0,0 +1,56 @@
+# Logs
+
+The log file is a stream of JSON structs. Each struct has a `sender` field that identifies the log type.
+
+The logs can be divided into the following categories:
+
+- **"app logs"**, internal logs used to debug SFTPGo:
+  - `sender` string. This is generally the package name that emits the log
+  - `time` string. Date/time with millisecond precision
+  - `level` string
+  - `message` string
+- **"transfer logs"**, SFTP/SCP transfer logs:
+  - `sender` string. `Upload` or `Download`
+  - `time` string. Date/time with millisecond precision
+  - `level` string
+  - `elapsed_ms`, int64. Elapsed time, as milliseconds, for the upload/download
+  - `size_bytes`, int64. Size, as bytes, of the download/upload
+  - `username`, string
+  - `file_path` string
+  - `connection_id` string. Unique connection identifier
+  - `protocol` string. `SFTP` or `SCP`
+- **"command logs"**, SFTP/SCP command logs:
+  - `sender` string. `Rename`, `Rmdir`, `Mkdir`, `Symlink`, `Remove`, `Chmod`, `Chown`, `Chtimes`, `Truncate`, `SSHCommand`
+  - `level` string
+  - `username`, string
+  - `file_path` string
+  - `target_path` string
+  - `filemode` string. Valid for sender `Chmod` otherwise empty
+  - `uid` integer. Valid for sender `Chown` otherwise -1
+  - `gid` integer. Valid for sender `Chown` otherwise -1
+  - `access_time` datetime as YYYY-MM-DDTHH:MM:SS. Valid for sender `Chtimes` otherwise empty
+  - `modification_time` datetime as YYYY-MM-DDTHH:MM:SS. Valid for sender `Chtimes` otherwise empty
+  - `size` int64. Valid for sender `Truncate` otherwise -1
+  - `ssh_command`, string. Valid for sender `SSHCommand` otherwise empty
+  - `connection_id` string. Unique connection identifier
+  - `protocol` string. `SFTP`, `SCP` or `SSH`
+- **"http logs"**, REST API logs:
+  - `sender` string. `httpd`
+  - `level` string
+  - `remote_addr` string. IP and port of the remote client
+  - `proto` string, for example `HTTP/1.1`
+  - `method` string. HTTP method (`GET`, `POST`, `PUT`, `DELETE` etc.)
+  - `user_agent` string
+  - `uri` string. Full uri
+  - `resp_status` integer. HTTP response status code
+  - `resp_size` integer. Size in bytes of the HTTP response
+  - `elapsed_ms` int64. Elapsed time, as milliseconds, to complete the request
+  - `request_id` string. Unique request identifier
+- **"connection failed logs"**, logs for failed attempts to initialize a connection. A connection can fail for an authentication error or other errors such as a client abort or a timeout if the login does not happen in two minutes
+  - `sender` string. `connection_failed`
+  - `level` string
+  - `username`, string. Can be empty if the connection is closed before an authentication attempt
+  - `client_ip` string.
+  - `protocol` string. Possible values are `SSH`, `FTP`, `DAV`
+  - `login_type` string. Can be `publickey`, `password`, `keyboard-interactive`, `publickey+password`, `publickey+keyboard-interactive` or `no_auth_tryed`
+  - `error` string. Optional error description

docs/metrics.md

@@ -0,0 +1,18 @@
+# Metrics
+
+SFTPGo exposes [Prometheus](https://prometheus.io/) metrics at the `/metrics` HTTP endpoint.
+Several counters and gauges are available, for example:
+
+- Total uploads and downloads
+- Total upload and download size
+- Total upload and download errors
+- Total executed SSH commands
+- Total SSH command errors
+- Number of active connections
+- Data provider availability
+- Total successful and failed logins using password, public key, keyboard interactive authentication or supported multi-step authentications
+- Total HTTP requests served and totals for response code
+- Go's runtime details about GC, number of gouroutines and OS threads
+- Process information like CPU, memory, file descriptor usage and start time
+
+Please check the `/metrics` page for more details.

docs/performance.md

@@ -0,0 +1,164 @@
+# Performance
+
+SFTPGo can easily saturate a Gigabit connection on low end hardware with no special configuration, this is generally enough for most use cases.
+
+For Multi-Gig connections, some performance improvements and comparisons with OpenSSH have been discussed [here](https://github.com/drakkan/sftpgo/issues/69), most of them have been included in the master branch. To summarize:
+
+- In current state with all performance improvements applied, SFTP performance is very close to OpenSSH however CPU usage is higher. SCP performance match OpenSSH.
+- The main bottlenecks are the encryption and the messages authentication, so if you can use a fast cipher with implicit messages authentication, such as `aes128-gcm@openssh.com`, you will get a big performance boost.
+- SCP protocol is much simpler than SFTP and so, the multi-platform, SFTPGo's SCP implementation performs better than SFTP.
+- Load balancing with HAProxy can greatly improve the performance if CPU not become the bottleneck.
+
+## Benchmark
+
+### Hardware specification
+
+**Server** ||
+--- | --- |
+OS| Debian 10.2 x64 |
+CPU| Ryzen5 3600 |
+RAM| 64GB 2400MHz ECC |
+Disk| Ramdisk |
+Ethernet| Mellanox ConnectX-3 40GbE|
+
+**Client** ||
+--- | --- |
+OS| Ubuntu 19.10 x64 |
+CPU| Threadripper 1920X |
+RAM| 64GB 2400MHz ECC |
+Disk| Ramdisk |
+Ethernet| Mellanox ConnectX-3 40GbE|
+
+### Test configurations
+
+- `Baseline`: SFTPGo version 0.9.6.
+- `Devel`: SFTPGo commit b0ed1905918b9dcc22f9a20e89e354313f491734, compiled with Golang 1.14.2. This is basically the same as v1.0.0 as far as performance is concerned.
+- `Optimized`: Various [optimizations](#Optimizations-applied) applied on top of `Devel`.
+- `Balanced`: Two optimized instances, running on localhost, load balanced by HAProxy 2.1.3.
+- `OpenSSH`: OpenSSH_7.9p1 Debian-10+deb10u2, OpenSSL 1.1.1d  10 Sep 2019
+
+Server's CPU is in Eco mode, you can expect better results in certain cases with a stronger CPU, especially multi-stream HAProxy balanced load.
+
+#### Cipher aes128-ctr
+
+The Message Authentication Code (MAC) used is `hmac-sha2-256`.
+
+##### SFTP
+
+Download:
+
+Stream|Baseline MB/s|Devel MB/s|Optimized MB/s|Balanced MB/s|OpenSSH MB/s|
+---|---|---|---|---|---|
+1|150|243|319|412|452|
+2|267|452|600|740|735|
+3|351|637|802|991|1045|
+4|414|811|1002|1192|1265|
+8|536|1451|1742|1552|1798|
+
+Upload:
+
+Stream|Baseline MB/s|Devel MB/s|Optimized MB/s|Balanced MB/s|OpenSSH MB/s|
+---|---|---|---|---|---|
+1|172|273|343|407|426|
+2|284|469|595|673|738|
+3|368|644|820|881|1090|
+4|446|851|1041|1026|1244|
+8|605|1210|1368|1273|1820|
+
+##### SCP
+
+Download:
+
+Stream|Baseline MB/s|Devel MB/s|Optimized MB/s|Balanced MB/s|OpenSSH MB/s|
+---|---|---|---|---|---|
+1|220|369|525|611|558|
+2|437|659|941|1048|856|
+3|635|1000|1365|1363|1201|
+4|787|1272|1664|1610|1415|
+8|1297|2129|2690|2100|1959|
+
+Upload:
+
+Stream|Baseline MB/s|Devel MB/s|Optimized MB/s|Balanced MB/s|OpenSSH MB/s|
+---|---|---|---|---|---|
+1|208|312|400|458|508|
+2|360|516|647|745|926|
+3|476|678|861|935|1254|
+4|576|836|1080|1099|1569|
+8|857|1161|1416|1433|2271|
+
+#### Cipher aes128-gcm@openssh.com
+
+With this cipher the messages authentication is implicit, no SHA256 computation is needed.
+
+##### SFTP
+
+Download:
+
+Stream|Baseline MB/s|Devel MB/s|Optimized MB/s|Balanced MB/s|OpenSSH MB/s|
+---|---|---|---|---|---|
+1|332|423|<--|583|443|
+2|533|755|<--|970|809|
+3|666|1045|<--|1249|1098|
+4|762|1276|<--|1461|1351|
+8|886|2064|<--|1825|1933|
+
+Upload:
+
+Stream|Baseline MB/s|Devel MB/s|Optimized MB/s|Balanced MB/s|OpenSSH MB/s|
+---|---|---|---|---|---|
+1|348|410|<--|527|469|
+2|596|729|<--|842|930|
+3|778|974|<--|1088|1341|
+4|886|1192|<--|1232|1494|
+8|1042|1578|<--|1433|1893|
+
+##### SCP
+
+Download:
+
+Stream|Baseline MB/s|Devel MB/s|Optimized MB/s|Balanced MB/s|OpenSSH MB/s|
+---|---|---|---|---|---|
+1|776|793|<--|832|578|
+2|1343|1415|<--|1435|938|
+3|1815|1878|<--|1877|1279|
+4|2192|2205|<--|2056|1567|
+8|3237|3287|<--|2493|2036|
+
+Upload:
+
+Stream|Baseline MB/s|Devel MB/s|Optimized MB/s|Balanced MB/s|OpenSSH MB/s|
+---|---|---|---|---|---|
+1|528|545|<--|608|584|
+2|872|849|<--|975|1019|
+3|1121|1138|<--|1217|1412|
+4|1367|1387|<--|1368|1755|
+8|1733|1744|<--|1664|2510|
+
+### Optimizations applied
+
+- AES-CTR optimization of Go compiler for x86_64, there is a [patch](https://go-review.googlesource.com/c/go/+/51670) that hasn't been merged yet, you can apply it yourself.
+
+### HAProxy configuration
+
+Here is the relevant HAProxy configuration used for the `Balanced` test configuration:
+
+```console
+frontend sftp
+    bind   :2222
+    mode   tcp
+    timeout  client  600s
+    default_backend sftpgo
+
+backend sftpgo
+    mode    tcp
+    balance roundrobin
+    timeout connect 10s
+    timeout server  600s
+    timeout queue   30s
+    option  tcp-check
+    tcp-check expect string SSH-2.0-
+
+    server sftpgo1 127.0.0.1:2022 check send-proxy-v2 weight 10 inter 10s rise 2 fall 3
+    server sftpgo2 127.0.0.1:2024 check send-proxy-v2 weight 10 inter 10s rise 2 fall 3
+```

docs/portable-mode.md

@@ -0,0 +1,99 @@
+# Portable mode
+
+SFTPGo allows to share a single directory on demand using the `portable` subcommand:
+
+```console
+sftpgo portable --help
+To serve the current working directory with auto generated credentials simply
+use:
+
+$ sftpgo portable
+
+Please take a look at the usage below to customize the serving parameters
+
+Usage:
+  sftpgo portable [flags]
+
+Flags:
+  -C, --advertise-credentials            If the SFTP/FTP service is
+                                         advertised via multicast DNS, this
+                                         flag allows to put username/password
+                                         inside the advertised TXT record
+  -S, --advertise-service                Advertise SFTP/FTP service using
+                                         multicast DNS
+      --allowed-extensions stringArray   Allowed file extensions case
+                                         insensitive. The format is
+                                         /dir::ext1,ext2.
+                                         For example: "/somedir::.jpg,.png"
+      --denied-extensions stringArray    Denied file extensions case
+                                         insensitive. The format is
+                                         /dir::ext1,ext2.
+                                         For example: "/somedir::.jpg,.png"
+  -d, --directory string                 Path to the directory to serve.
+                                         This can be an absolute path or a path
+                                         relative to the current directory
+                                          (default ".")
+  -f, --fs-provider int                  0 means local filesystem,
+                                         1 Amazon S3 compatible,
+                                         2 Google Cloud Storage
+      --ftpd-cert string                 Path to the certificate file for FTPS
+      --ftpd-key string                  Path to the key file for FTPS
+      --ftpd-port int                    0 means a random unprivileged port,
+                                         < 0 disabled (default -1)
+      --gcs-automatic-credentials int    0 means explicit credentials using
+                                         a JSON credentials file, 1 automatic
+                                          (default 1)
+      --gcs-bucket string
+      --gcs-credentials-file string      Google Cloud Storage JSON credentials
+                                         file
+      --gcs-key-prefix string            Allows to restrict access to the
+                                         virtual folder identified by this
+                                         prefix and its contents
+      --gcs-storage-class string
+  -h, --help                             help for portable
+  -l, --log-file-path string             Leave empty to disable logging
+  -v, --log-verbose                      Enable verbose logs
+  -p, --password string                  Leave empty to use an auto generated
+                                         value
+  -g, --permissions strings              User's permissions. "*" means any
+                                         permission (default [list,download])
+  -k, --public-key strings
+      --s3-access-key string
+      --s3-access-secret string
+      --s3-bucket string
+      --s3-endpoint string
+      --s3-key-prefix string             Allows to restrict access to the
+                                         virtual folder identified by this
+                                         prefix and its contents
+      --s3-region string
+      --s3-storage-class string
+      --s3-upload-concurrency int        How many parts are uploaded in
+                                         parallel (default 2)
+      --s3-upload-part-size int          The buffer size for multipart uploads
+                                         (MB) (default 5)
+  -s, --sftpd-port int                   0 means a random unprivileged port
+  -c, --ssh-commands strings             SSH commands to enable.
+                                         "*" means any supported SSH command
+                                         including scp
+                                          (default [md5sum,sha1sum,cd,pwd,scp])
+  -u, --username string                  Leave empty to use an auto generated
+                                         value
+      --webdav-cert string               Path to the certificate file for WebDAV
+                                         over HTTPS
+      --webdav-key string                Path to the key file for WebDAV over
+                                         HTTPS
+      --webdav-port int                  0 means a random unprivileged port,
+                                         < 0 disabled (default -1)
+```
+
+In portable mode, SFTPGo can advertise the SFTP/FTP services and, optionally, the credentials via multicast DNS, so there is a standard way to discover the service and to automatically connect to it.
+
+Here is an example of the advertised SFTP service including credentials as seen using `avahi-browse`:
+
+```console
+= enp0s31f6 IPv4 SFTPGo portable 53705                         SFTP File Transfer   local
+   hostname = [p1.local]
+   address = [192.168.1.230]
+   port = [53705]
+   txt = ["password=EWOo6pJe" "user=user" "version=0.9.3-dev-b409523-dirty-2019-10-26T13:43:32Z"]
+```

docs/post-connect-hook.md

@@ -0,0 +1,26 @@
+# Post-connect hook
+
+This hook is executed as soon as a new connection is established. It notifies the connection's IP address and protocol. Based on the received response, the connection is accepted or rejected. Combining this hook with the [Post-login hook](./post-login-hook.md) you can implement your own (even for Protocol) blacklist/whitelist of IP addresses.
+
+Please keep in mind that you can easily configure specialized program such as [Fail2ban](http://www.fail2ban.org/) for brute force protection. Executing a hook for each connection can be heavy.
+
+The `post-connect-hook` can be defined as the absolute path of your program or an HTTP URL.
+
+If the hook defines an external program it can read the following environment variables:
+
+- `SFTPGO_CONNECTION_IP`
+- `SFTPGO_CONNECTION_PROTOCOL`
+
+If the external command completes with a zero exit status the connection will be accepted otherwise rejected.
+
+Previous global environment variables aren't cleared when the script is called.
+The program must finish within 20 seconds.
+
+If the hook defines an HTTP URL then this URL will be invoked as HTTP GET with the following query parameters:
+
+- `ip`
+- `protocol`
+
+The connection is accepted if the HTTP response code is `200` otherwise rejected.
+
+The HTTP request will use the global configuration for HTTP clients.

docs/post-login-hook.md

@@ -0,0 +1,36 @@
+# Post-login hook
+
+This hook is executed after a login or after closing a connection for authentication timeout. Defining an appropriate `post_login_scope` you can get notifications for failed logins, successful logins or both.
+
+Combining this hook with the [Post-connect hook](./post-connect-hook.md) you can implement your own (even for Protocol) blacklist/whitelist of IP addresses.
+
+Please keep in mind that you can easily configure specialized program such as [Fail2ban](http://www.fail2ban.org/) for brute force protection. Executing a hook after each login can be heavy.
+
+The `post-login-hook` can be defined as the absolute path of your program or an HTTP URL.
+
+If the hook defines an external program it can reads the following environment variables:
+
+- `SFTPGO_LOGIND_USER`, username, can be empty if the connection is closed for authentication timeout
+- `SFTPGO_LOGIND_IP`
+- `SFTPGO_LOGIND_METHOD`, possible values are `publickey`, `password`, `keyboard-interactive`, `publickey+password`, `publickey+keyboard-interactive` or `no_auth_tryed`
+- `SFTPGO_LOGIND_STATUS`, 1 means login OK, 0 login KO
+- `SFTPGO_LOGIND_PROTOCOL`, possible values are `SSH`, `FTP`, `DAV`
+
+Previous global environment variables aren't cleared when the script is called.
+The program must finish within 20 seconds.
+
+If the hook is an HTTP URL then it will be invoked as HTTP POST. The request body will contain a JSON serialized struct with the following fields:
+
+- `username`
+- `login_method`
+- `ip`
+- `protocol`
+- `status`
+
+The HTTP request will use the global configuration for HTTP clients.
+
+The `post_login_scope` supports the following configuration values:
+
+- `0` means notify both failed and successful logins
+- `1` means notify failed logins. Connections closed for authentication timeout are notified as failed connections. You will get an empty username in this case
+- `2` means notify successful logins

docs/profiling.md

@@ -0,0 +1,23 @@
+# Profiling SFTPGo
+
+The built-in profiler lets you collect CPU profiles, traces, allocations and heap profiles that allow to identify and correct specific bottlenecks.
+You can enable the built-in profiler using the `--profiler` command flag.
+
+Profiling data are exposed via HTTP/HTTPS in the format expected by the [pprof](https://github.com/google/pprof/blob/master/doc/README.md) visualization tool. You can find the index page at the URL `/debug/pprof/`.
+
+The following profiles are available, you can obtain them via HTTP GET requests:
+
+- `allocs`, a sampling of all past memory allocations
+- `block`, stack traces that led to blocking on synchronization primitives
+- `goroutine`, stack traces of all current goroutines
+- `heap`, a sampling of memory allocations of live objects. You can specify the `gc` GET parameter to run GC before taking the heap sample
+- `mutex`, stack traces of holders of contended mutexes
+- `profile`, CPU profile. You can specify the duration in the `seconds` GET parameter. After you get the profile file, use the `go tool pprof` command to investigate the profile
+- `threadcreate`, stack traces that led to the creation of new OS threads
+- `trace`, a trace of execution of the current program. You can specify the duration in the `seconds` GET parameter. After you get the trace file, use the `go tool trace` command to investigate the trace
+
+For example you can:
+
+- download a 30 seconds CPU profile from the URL `/debug/pprof/profile?seconds=30`
+- download a sampling of memory allocations of live objects from the URL `/debug/pprof/heap?gc=1`
+- download a sampling of all past memory allocations from the URL `/debug/pprof/allocs`

docs/rest-api.md

@@ -0,0 +1,35 @@
+# REST API
+
+SFTPGo exposes REST API to manage, backup, and restore users and folders, and to get real time reports of the active connections with the ability to forcibly close a connection.
+
+If quota tracking is enabled in the configuration file, then the used size and number of files are updated each time a file is added/removed. If files are added/removed not using SFTP/SCP, or if you change `track_quota` from `2` to `1`, you can rescan the users home dir and update the used quota using the REST API.
+
+REST API can be protected using HTTP basic authentication and exposed via HTTPS. If you need more advanced security features, you can setup a reverse proxy using an HTTP Server such as Apache or NGNIX.
+
+For example, you can keep SFTPGo listening on localhost and expose it externally configuring a reverse proxy using Apache HTTP Server this way:
+
+```shell
+ProxyPass /api/v1 http://127.0.0.1:8080/api/v1
+ProxyPassReverse /api/v1 http://127.0.0.1:8080/api/v1
+```
+
+and you can add authentication with something like this:
+
+```shell
+<Location /api/v1>
+  AuthType Digest
+  AuthName "Private"
+  AuthDigestDomain "/api/v1"
+  AuthDigestProvider file
+  AuthUserFile "/etc/httpd/conf/auth_digest"
+  Require valid-user
+</Location>
+```
+
+and, of course, you can configure the web server to use HTTPS.
+
+The OpenAPI 3 schema for the exposed API can be found inside the source tree: [openapi.yaml](../httpd/schema/openapi.yaml "OpenAPI 3 specs").
+
+A sample CLI client for the REST API can be found inside the source tree [rest-api-cli](../examples/rest-api-cli) directory.
+
+You can also generate your own REST client in your preferred programming language, or even bash scripts, using an OpenAPI generator such as [swagger-codegen](https://github.com/swagger-api/swagger-codegen) or [OpenAPI Generator](https://openapi-generator.tech/)

docs/s3.md

@@ -0,0 +1,38 @@
+# S3 Compatible Object Storage backends
+
+To connect SFTPGo to AWS, you need to specify credentials, a `bucket` and a `region`. Here is the list of available [AWS regions](https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/using-regions-availability-zones.html#concepts-available-regions). For example, if your bucket is at `Frankfurt`, you have to set the region to `eu-central-1`. You can specify an AWS [storage class](https://docs.aws.amazon.com/AmazonS3/latest/dev/storage-class-intro.html) too. Leave it blank to use the default AWS storage class. An endpoint is required if you are connecting to a Compatible AWS Storage such as [MinIO](https://min.io/).
+
+AWS SDK has different options for credentials. [More Detail](https://docs.aws.amazon.com/sdk-for-go/v1/developer-guide/configuring-sdk.html). We support:
+
+1. Providing [Access Keys](https://docs.aws.amazon.com/general/latest/gr/aws-sec-cred-types.html#access-keys-and-secret-access-keys).
+2. Use IAM roles for Amazon EC2
+3. Use IAM roles for tasks if your application uses an ECS task definition
+
+So, you need to provide access keys to activate option 1, or leave them blank to use the other ways to specify credentials.
+
+Most S3 backends require HTTPS connections so if you are running SFTPGo as docker image please be sure to uncomment the line that installs `ca-certificates`, inside your `Dockerfile`, to be able to properly verify certificate authorities.
+
+Specifying a different `key_prefix`, you can assign different "folders" of the same bucket to different users. This is similar to a chroot directory for local filesystem. Each SFTP/SCP user can only access the assigned folder and its contents. The folder identified by `key_prefix` does not need to be pre-created.
+
+SFTPGo uses multipart uploads and parallel downloads for storing and retrieving files from S3.
+
+For multipart uploads you can customize the parts size and the upload concurrency. Please note that if the upload bandwidth between the SFTP client and SFTPGo is greater than the upload bandwidth between SFTPGo and S3 then the SFTP client have to wait for the upload of the last parts to S3 after it ends the file upload to SFTPGo, and it may time out. Keep this in mind if you customize these parameters.
+
+The configured bucket must exist.
+
+Some SFTP commands don't work over S3:
+
+- `symlink` and `chtimes` will fail
+- `chown` and `chmod` are silently ignored
+- `truncate` is not supported
+- opening a file for both reading and writing at the same time is not supported
+- upload resume is not supported
+- upload mode `atomic` is ignored since S3 uploads are already atomic
+
+Other notes:
+
+- `rename` is a two step operation: server-side copy and then deletion. So, it is not atomic as for local filesystem.
+- We don't support renaming non empty directories since we should rename all the contents too and this could take a long time: think about directories with thousands of files; for each file we should do an AWS API call.
+- For server side encryption, you have to configure the mapped bucket to automatically encrypt objects.
+- A local home directory is still required to store temporary files.
+- Clients that require advanced filesystem-like features such as `sshfs` are not supported.

docs/service.md

@@ -0,0 +1,145 @@
+# Running SFTPGo as a service
+
+Download a binary SFTPGo [release](https://github.com/drakkan/sftpgo/releases) or a build artifact for the [latest commit](https://github.com/drakkan/sftpgo/actions) or build SFTPGo yourself.
+
+Run the following instructions from the directory that contains the sftpgo binary and the accompanying files.
+
+## Linux
+
+The easiest way to run SFTPGo as a service is to download and install the pre-compiled deb/rpm package or use one of the Arch Linux PKGBUILDs we maintain.
+
+This section describes the procedure to use if you prefer to build SFTPGo yourself or if you want to download and configure a pre-built release as tar.
+
+A `systemd` sample [service](../init/sftpgo.service "systemd service") can be found inside the source tree.
+
+Here are some basic instructions to run SFTPGo as service using a dedicated `sftpgo` system account.
+
+Please run the following commands from the directory where you downloaded/compiled SFTPGo:
+
+```bash
+# create the sftpgo user and group
+sudo groupadd --system sftpgo
+sudo useradd --system \
+  --gid sftpgo \
+  --no-create-home \
+  --home-dir /var/lib/sftpgo \
+  --shell /usr/sbin/nologin \
+  --comment "SFTPGo user" \
+  sftpgo
+# create the required directories
+sudo mkdir -p /etc/sftpgo \
+  /var/lib/sftpgo \
+  /usr/share/sftpgo
+
+# install the sftpgo executable
+sudo install -Dm755 sftpgo /usr/bin/sftpgo
+# install the default configuration file, edit it if required
+sudo install -Dm644 sftpgo.json /etc/sftpgo/
+# override some configuration keys using environment variables
+sudo sh -c 'echo "SFTPGO_HTTPD__TEMPLATES_PATH=/usr/share/sftpgo/templates" > /etc/sftpgo/sftpgo.env'
+sudo sh -c 'echo "SFTPGO_HTTPD__STATIC_FILES_PATH=/usr/share/sftpgo/static" >> /etc/sftpgo/sftpgo.env'
+sudo sh -c 'echo "SFTPGO_HTTPD__BACKUPS_PATH=/var/lib/sftpgo/backups" >> /etc/sftpgo/sftpgo.env'
+sudo sh -c 'echo "SFTPGO_DATA_PROVIDER__CREDENTIALS_PATH=/var/lib/sftpgo/credentials" >> /etc/sftpgo/sftpgo.env'
+# if you use a file based data provider such as sqlite or bolt consider to set the database path too, for example:
+#sudo sh -c 'echo "SFTPGO_DATA_PROVIDER__NAME=/var/lib/sftpgo/sftpgo.db" >> /etc/sftpgo/sftpgo.env'
+# also set the provider's PATH as env var to get initprovider to work with SQLite provider:
+#export SFTPGO_DATA_PROVIDER__NAME=/var/lib/sftpgo/sftpgo.db
+# install static files and templates for the web UI
+sudo cp -r static templates /usr/share/sftpgo/
+# set files and directory permissions
+sudo chown -R sftpgo:sftpgo /etc/sftpgo /var/lib/sftpgo
+sudo chmod 750 /etc/sftpgo /var/lib/sftpgo
+sudo chmod 640 /etc/sftpgo/sftpgo.json /etc/sftpgo/sftpgo.env
+# initialize the configured data provider
+# if you want to use MySQL or PostgreSQL you need to create the configured database before running the initprovider command
+sudo -E su - sftpgo -m -s /bin/bash -c 'sftpgo initprovider -c /etc/sftpgo'
+# install the systemd service
+sudo install -Dm644 init/sftpgo.service /etc/systemd/system
+# start the service
+sudo systemctl start sftpgo
+# verify that the service is started
+sudo systemctl status sftpgo
+# automatically start sftpgo on boot
+sudo systemctl enable sftpgo
+# optional, install the REST API CLI. It requires python-requests to run
+sudo install -Dm755 examples/rest-api-cli/sftpgo_api_cli /usr/bin/sftpgo_api_cli
+# optional, create shell completion script, for example for bash
+sudo sh -c '/usr/bin/sftpgo gen completion bash > /usr/share/bash-completion/completions/sftpgo'
+# optional, create man pages
+sudo /usr/bin/sftpgo gen man -d /usr/share/man/man1
+```
+
+## macOS
+
+For macOS, a `launchd` sample [service](../init/com.github.drakkan.sftpgo.plist "launchd plist") can be found inside the source tree. The `launchd` plist assumes that SFTPGo has `/usr/local/opt/sftpgo` as base directory.
+
+Here are some basic instructions to run SFTPGo as service, please run the following commands from the directory where you downloaded SFTPGo:
+
+```bash
+# create the required directories
+sudo mkdir -p /usr/local/opt/sftpgo/init \
+  /usr/local/opt/sftpgo/var/lib \
+  /usr/local/opt/sftpgo/usr/share \
+  /usr/local/opt/sftpgo/var/log \
+  /usr/local/opt/sftpgo/etc \
+  /usr/local/opt/sftpgo/bin
+
+# install sftpgo executable
+sudo cp sftpgo /usr/local/opt/sftpgo/bin/
+# install the launchd service
+sudo cp init/com.github.drakkan.sftpgo.plist /usr/local/opt/sftpgo/init/
+sudo chown root:wheel /usr/local/opt/sftpgo/init/com.github.drakkan.sftpgo.plist
+# install the default configuration file, edit it if required
+sudo cp sftpgo.json /usr/local/opt/sftpgo/etc/
+# install static files and templates for the web UI
+sudo cp -r static templates /usr/local/opt/sftpgo/usr/share/
+# initialize the configured data provider
+# if you want to use MySQL or PostgreSQL you need to create the configured database before running the initprovider command
+sudo /usr/local/opt/sftpgo/bin/sftpgo initprovider -c /usr/local/opt/sftpgo/etc/
+# add sftpgo to the launch daemons
+sudo ln -s /usr/local/opt/sftpgo/init/com.github.drakkan.sftpgo.plist /Library/LaunchDaemons/com.github.drakkan.sftpgo.plist
+# start the service and enable it to start on boot
+sudo launchctl load -w /Library/LaunchDaemons/com.github.drakkan.sftpgo.plist
+# verify that the service is started
+sudo launchctl list com.github.drakkan.sftpgo
+# optional, install the REST API CLI. It requires python-requests to run, this python module is not installed by default
+sudo cp examples/rest-api-cli/sftpgo_api_cli /usr/local/opt/sftpgo/bin/
+```
+
+## Windows
+
+On Windows, you can register SFTPGo as Windows Service. Take a look at the CLI usage to learn how to do this:
+
+```powershell
+PS> sftpgo.exe service --help
+Manage SFTPGo Windows Service
+
+Usage:
+  sftpgo service [command]
+
+Available Commands:
+  install     Install SFTPGo as Windows Service
+  reload      Reload the SFTPGo Windows Service sending a "paramchange" request
+  rotatelogs  Signal to the running service to rotate the logs
+  start       Start SFTPGo Windows Service
+  status      Retrieve the status for the SFTPGo Windows Service
+  stop        Stop SFTPGo Windows Service
+  uninstall   Uninstall SFTPGo Windows Service
+
+Flags:
+  -h, --help   help for service
+
+Use "sftpgo service [command] --help" for more information about a command.
+```
+
+The `install` subcommand accepts the same flags that are valid for `serve`.
+
+After installing as a Windows Service, please remember to allow network access to the SFTPGo executable using something like this:
+
+```powershell
+PS> netsh advfirewall firewall add rule name="SFTPGo Service" dir=in action=allow program="C:\Program Files\SFTPGo\sftpgo.exe"
+```
+
+Or through the Windows Firewall GUI.
+
+The Windows installer will register the service and allow network access for it automatically.

docs/ssh-commands.md

@@ -0,0 +1,46 @@
+# SSH commands
+
+Some SSH commands are implemented directly inside SFTPGo, while for others we use system commands that need to be installed and in your system's `PATH`.
+
+For system commands we have no direct control on file creation/deletion and so there are some limitations:
+
+- we cannot allow them if the target directory contains virtual folders or file extensions filters
+- system commands work only on local filyestem
+- we cannot avoid to leak real filesystem paths
+- quota check is suboptimal
+- maximum size restriction on single file is not respected
+
+ If quota is enabled and SFTPGo receives a system command, the used size and number of files are checked at the command start and not while new files are created/deleted. While the command is running the number of files is not checked, the remaining size is calculated as the difference between the max allowed quota and the used one, and it is checked against the bytes transferred via SSH. The command is aborted if it uploads more bytes than the remaining allowed size calculated at the command start. Anyway, we only see the bytes that the remote command sends to the local one via SSH. These bytes contain both protocol commands and files, and so the size of the files is different from the size transferred via SSH: for example, a command can send compressed files, or a protocol command (few bytes) could delete a big file. To mitigate these issues, quotas are recalculated at the command end with a full scan of the directory specified for the system command. This could be heavy for big directories. If you need system commands and quotas you could consider disabling quota restrictions and periodically update quota usage yourself using the REST API.
+
+ For these reasons we should limit system commands usage as much as possible, we currently support the following system commands:
+
+- `git-receive-pack`, `git-upload-pack`, `git-upload-archive`. These commands enable support for Git repositories over SSH. They need to be installed and in your system's `PATH`.
+- `rsync`. The `rsync` command needs to be installed and in your system's `PATH`.
+
+At least the following permissions are required to be able to run system commands:
+
+- `list`
+- `download`
+- `upload`
+- `create_dirs`
+- `overwrite`
+- `delete`
+
+For `rsync`  we cannot avoid that it creates symlinks so if the `create_symlinks` permission is granted we add the option `--safe-links`, if it is not already set, to the received `rsync` command. This should prevent to create symlinks that point outside the home directory.
+If the user cannot create symlinks we add the option `--munge-links`, if it is not already set, to the received `rsync` command. This should make symlinks unusable (but manually recoverable).
+
+SFTPGo supports the following built-in SSH commands:
+
+- `scp`, SFTPGo implements the SCP protocol so we can support it for cloud filesystems too and we can avoid the other system commands limitations. SCP between two remote hosts is supported using the `-3` scp option.
+- `md5sum`, `sha1sum`, `sha256sum`, `sha384sum`, `sha512sum`. Useful to check message digests for uploaded files.
+- `cd`, `pwd`. Some SFTP clients do not support the SFTP SSH_FXP_REALPATH packet type, so they use `cd` and `pwd` SSH commands to get the initial directory. Currently `cd` does nothing and `pwd` always returns the `/` path.
+- `sftpgo-copy`. This is a built-in copy implementation. It allows server side copy for files and directories. The first argument is the source file/directory and the second one is the destination file/directory, for example `sftpgo-copy <src> <dst>`. The command will fail if the destination exists. Copy for directories spanning virtual folders is not supported. Only local filesystem is supported: recursive copy for Cloud Storage filesystems requires a new request for every file in any case, so a real server side copy is not possible.
+- `sftpgo-remove`. This is a built-in remove implementation. It allows to remove single files and to recursively remove directories. The first argument is the file/directory to remove, for example `sftpgo-remove <dst>`. Only local filesystem is supported: recursive remove for Cloud Storage filesystems requires a new request for every file in any case, so a server side remove is not possible.
+
+The following SSH commands are enabled by default:
+
+- `md5sum`
+- `sha1sum`
+- `cd`
+- `pwd`
+- `scp`

docs/virtual-folders.md

@@ -0,0 +1,31 @@
+# Virtual Folders
+
+A virtual folder is a mapping between an SFTP/SCP virtual path and a filesystem path outside the user home directory.
+The specified paths must be absolute and the virtual path cannot be "/", it must be a sub directory.
+The parent directory to the specified virtual path must exist. SFTPGo will try to automatically create any missing parent directory for the configured virtual folders at user login.
+
+For each virtual folder, the following properties can be configured:
+
+- `mapped_path`, the full absolute path to the filesystem path to expose as virtual folder
+- `virtual_path`, the SFTP/SCP absolute path to use to expose the mapped path
+- `quota_size`, maximum size allowed as bytes. 0 means unlimited, -1 included in user quota
+- `quota_files`, maximum number of files allowed. 0 means unlimited, -1 included in user quota
+
+For example if you configure `/tmp/mapped` or `C:\mapped` as mapped path and `/vfolder` as virtual path then SFTP/SCP users can access the mapped path via the `/vfolder` SFTP path.
+
+The same virtual folder, identified by the `mapped_path`, can be shared among users and different folder quota limits for each user are supported.
+Folder quota limits can also be included inside the user quota but in this case the folder is considered "private" and sharing it with other users will break user quota calculation.
+
+You don't need to create virtual folders, inside the data provider, to associate them to the users: any missing virtual folder will be automatically created when you add/update a user. You only have to create the folder on the filesystem.
+
+Using the REST API you can:
+
+- monitor folders quota usage
+- scan quota for folders
+- inspect the relationships among users and folders
+- delete a virtual folder. SFTPGo removes folders from the data provider, no files deletion will occur
+
+If you remove a folder, from the data provider, any users relationships will be cleared up. If the deleted folder is included inside the user quota you need to do a user quota scan to update its quota. An orphan virtual folder will not be automatically deleted since if you add it again later then a quota scan is needed and it could be quite expensive, anyway you can easily list the orphan folders using the REST API and delete them if they are not needed anymore.
+
+Overlapping virtual paths are not allowed for the same user, overlapping mapped paths are allowed only if quota tracking is globally disabled inside the configuration file (`track_quota` must be set to `0`).
+Virtual folders are supported for local filesystem only.

docs/web-admin.md

@@ -0,0 +1,8 @@
+# Web Admin
+
+You can easily build your own interface using the exposed REST API. Anyway, SFTPGo also provides a very basic built-in web interface that allows you to manage users and connections.
+With the default `httpd` configuration, the web admin is available at the following URL:
+
+[http://127.0.0.1:8080/web](http://127.0.0.1:8080/web)
+
+The web interface can be protected using HTTP basic authentication and exposed via HTTPS. If you need more advanced security features, you can setup a reverse proxy as explained for the [REST API](./rest-api.md).

docs/webdav.md

@@ -0,0 +1,28 @@
+# WebDAV
+
+The experimental `WebDAV` support can be enabled by setting a `bind_port` inside the `webdavd` configuration section.
+
+Each user has his own path like `http/s://<SFTPGo ip>:<WevDAVPORT>/<username>` and it must authenticate using password credentials.
+
+WebDAV is quite a different protocol than SCP/FTP, there is no session concept, each command is a separate HTTP request and must be authenticated, performance can be greatly improved enabling caching for the authenticated users (it is enabled by default). This way SFTPGo don't need to do a dataprovider query and a password check for each request.
+If you enable quota support a dataprovider query is required, to update the user quota, after each file upload.
+
+The caching configuration allows to set:
+
+- `expiration_time` in minutes. If a user is cached for more than the specified minutes it will be removed from the cache and a new dataprovider query will be performed. Please note that the `last_login` field will not be updated and `external_auth_hook`, `pre_login_hook` and `check_password_hook` will not be executed if the user is obtained from the cache.
+- `max_size`. Maximum number of users to cache. When this limit is reached the user with the oldest expiration date will be removed from the cache. 0 means no limit however the cache size cannot exceed the number of users so if you have a small number of users you can leave this setting to 0.
+
+Users are automatically removed from the cache after an update/delete.
+
+WebDAV should work as expected for most use cases but there are some minor issues and some missing features.
+
+Know issues:
+
+- removing a directory tree on Cloud Storage backends could generate a `not found` error when removing the last (virtual) directory. This happens if the client cycles the directories tree itself and removes files and directories one by one instead of issuing a single remove command
+- the used [WebDAV library](https://pkg.go.dev/golang.org/x/net/webdav?tab=doc) asks to open a file to execute a `stat` and sometimes reads some bytes to find the content type. We are unable to distinguish a `stat` from a `download` for now, so to be able to properly list a directory you need to grant both `list` and `download` permissions
+- the used `WebDAV library` not always returns a proper error code/message, most of the times it simply returns `Method not Allowed`. I'll try to improve the library error codes in the future
+- if an object within a directory cannot be accessed, for example due to OS permissions issues or because is a missing mapped path for a virtual folder, the directory listing will fail. In SFTP/FTP the directory listing will succeed and you'll only get an error if you try to access to the problematic file/directory
+
+We plan to add [Dead Properties](https://tools.ietf.org/html/rfc4918#section-3) support in future releases. We need a design decision here, probably the best solution is to store dead properties inside the data provider but this could increase a lot its size. Alternately we could store them on disk for local filesystem and add as metadata for Cloud Storage, this means that we need to do a separate `HEAD` request to retrieve dead properties for an S3 file. For big folders will do a lot of requests to the Cloud Provider, I don't like this solution. Another option is to expose a hook and allow you to implement `dead properties` outside SFTPGo.
+
+If you find any other quirks or problems please let us know opening a GitHub issue, thank you!

examples/OTP/authy/README.md

@@ -0,0 +1,58 @@
+# Authy
+
+These example show how-to integrate [Twilio Authy API](https://www.twilio.com/docs/authy/api) for One-Time-Password logins.
+
+The examples assume that the user has the free [Authy app](https://authy.com/) installed and uses it to generate offline [TOTP](https://en.wikipedia.org/wiki/Time-based_One-time_Password_algorithm) codes (soft tokens).
+
+You first need to [create an Authy Application in the Twilio Console](https://twilio.com/console/authy/applications?_ga=2.205553366.451688189.1597667213-1526360003.1597667213), then you can create a new Authy user and store a reference to the matching SFTPGo account.
+
+Verify that your Authy application is successfully registered:
+
+```bash
+export AUTHY_API_KEY=<your api key here>
+curl 'https://api.authy.com/protected/json/app/details' -H "X-Authy-API-Key: $AUTHY_API_KEY"
+```
+
+now create an Authy user:
+
+```bash
+curl -XPOST "https://api.authy.com/protected/json/users/new" \
+-H "X-Authy-API-Key: $AUTHY_API_KEY" \
+--data-urlencode user[email]="user@domain.com" \
+--data-urlencode user[cellphone]="317-338-9302" \
+--data-urlencode user[country_code]="54"
+```
+
+The response is something like this:
+
+```json
+{"message":"User created successfully.","user":{"id":xxxxxxxx},"success":true}
+```
+
+Save the user id somewhere and add a reference to the matching SFTPGo account.
+
+After this step you can use the Authy app installed on your phone to generate TOTP codes.
+
+Now you can verify the token using an HTTP GET request:
+
+```bash
+export TOKEN=<TOTP you read from Authy app>
+export AUTHY_ID=<user id>
+curl -i "https://api.authy.com/protected/json/verify/${TOKEN}/${AUTHY_ID}" \
+    -H "X-Authy-API-Key: $AUTHY_API_KEY"
+```
+
+So inside your hook you need to check:
+
+- the HTTP response code for the verify request, it must be `200`
+- the JSON reponse body, it must contains the key `success` with the value `true` (as string)
+
+If these conditions are met the token is valid and you allow the user to login.
+
+We provide the following examples:
+
+- [Keyboard interactive authentication](./keyint/README.md) for 2FA using password + Authy one time token.
+- [External authentication](./extauth/README.md) using Authy one time tokens as passwords.
+- [Check password hook](./checkpwd/README.md) for 2FA using a password consisting of a fixed string and a One Time Token.
+
+Please note that these are sample programs not intended for production use, you should write your own hook based on them and you should prefer HTTP based hooks if performance is a concern.

examples/OTP/authy/checkpwd/README.md

@@ -0,0 +1,3 @@
+# Authy 2FA via check password hook
+
+This example shows how to use 2FA via the check password hook using a password consisting of a fixed part and an Authy TOTP token. The hook will check the TOTP token using the Authy API and SFTPGo will check the fixed part. Please read the [sample code](./main.go), it should be self explanatory.

examples/OTP/authy/checkpwd/go.mod

@@ -0,0 +1,3 @@
+module github.com/drakkan/sftpgo/authy/checkpwd
+
+go 1.15

examples/OTP/authy/checkpwd/main.go

@@ -0,0 +1,106 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"log"
+	"net/http"
+	"os"
+	"time"
+)
+
+type userMapping struct {
+	SFTPGoUsername string
+	AuthyID        int64
+	AuthyAPIKey    string
+}
+
+type checkPasswordResponse struct {
+	// 0 KO, 1 OK, 2 partial success
+	Status int `json:"status"`
+	// for status == 2 this is the password that SFTPGo will check against the one stored
+	// inside the data provider
+	ToVerify string `json:"to_verify"`
+}
+
+var (
+	mapping []userMapping
+)
+
+func init() {
+	// this is for demo only, you probably want to get this mapping dynamically, for example using a database query
+	mapping = append(mapping, userMapping{
+		SFTPGoUsername: "<SFTPGo username>",
+		AuthyID:        1234567,
+		AuthyAPIKey:    "<your api key>",
+	})
+}
+
+func printResponse(status int, toVerify string) {
+	r := checkPasswordResponse{
+		Status:   status,
+		ToVerify: toVerify,
+	}
+	resp, _ := json.Marshal(r)
+	fmt.Printf("%v\n", string(resp))
+	if status > 0 {
+		os.Exit(0)
+	} else {
+		os.Exit(1)
+	}
+}
+
+func main() {
+	// get credentials from env vars
+	username := os.Getenv("SFTPGO_AUTHD_USERNAME")
+	password := os.Getenv("SFTPGO_AUTHD_PASSWORD")
+
+	for _, m := range mapping {
+		if m.SFTPGoUsername == username {
+			// Authy token len is 7, we assume that we have the password followed by the token
+			pwdLen := len(password)
+			if pwdLen <= 7 {
+				printResponse(0, "")
+			}
+			pwd := password[:pwdLen-7]
+			authyToken := password[pwdLen-7:]
+			// now verify the authy token and instruct SFTPGo to check the password if the token is OK
+			url := fmt.Sprintf("https://api.authy.com/protected/json/verify/%v/%v", authyToken, m.AuthyID)
+			req, err := http.NewRequest(http.MethodGet, url, nil)
+			if err != nil {
+				log.Fatal(err)
+			}
+			req.Header.Set("X-Authy-API-Key", m.AuthyAPIKey)
+			httpClient := &http.Client{
+				Timeout: 10 * time.Second,
+			}
+			resp, err := httpClient.Do(req)
+			if err != nil {
+				printResponse(0, "")
+			}
+			defer resp.Body.Close()
+			if resp.StatusCode != http.StatusOK {
+				// status code 200 is expected
+				printResponse(0, "")
+			}
+			var authyResponse map[string]interface{}
+			respBody, err := ioutil.ReadAll(resp.Body)
+			if err != nil {
+				printResponse(0, "")
+			}
+			err = json.Unmarshal(respBody, &authyResponse)
+			if err != nil {
+				printResponse(0, "")
+			}
+			if authyResponse["success"].(string) == "true" {
+				printResponse(2, pwd)
+			}
+			printResponse(0, "")
+			break
+		}
+	}
+
+	// no mapping found
+	printResponse(0, "")
+}

examples/OTP/authy/extauth/README.md

@@ -0,0 +1,3 @@
+# Authy external authentication
+
+This example shows how to use Authy TOTP token as password for SFTPGo users. Please read the [sample code](./main.go), it should be self explanatory.

examples/OTP/authy/extauth/go.mod

@@ -0,0 +1,3 @@
+module github.com/drakkan/sftpgo/authy/extauth
+
+go 1.15

examples/OTP/authy/extauth/main.go

@@ -0,0 +1,109 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"log"
+	"net/http"
+	"os"
+	"path/filepath"
+	"time"
+)
+
+type userMapping struct {
+	SFTPGoUsername string
+	AuthyID        int64
+	AuthyAPIKey    string
+}
+
+// we assume that the SFTPGo already exists, we only check the one time token.
+// If you need to create the SFTPGo user more fields are needed here
+type minimalSFTPGoUser struct {
+	Status      int                 `json:"status,omitempty"`
+	Username    string              `json:"username"`
+	HomeDir     string              `json:"home_dir,omitempty"`
+	Permissions map[string][]string `json:"permissions"`
+}
+
+var (
+	mapping []userMapping
+)
+
+func init() {
+	// this is for demo only, you probably want to get this mapping dynamically, for example using a database query
+	mapping = append(mapping, userMapping{
+		SFTPGoUsername: "<SFTPGo username>",
+		AuthyID:        1234567,
+		AuthyAPIKey:    "<your api key>",
+	})
+}
+
+func printResponse(username string) {
+	u := minimalSFTPGoUser{
+		Username: username,
+		Status:   1,
+		HomeDir:  filepath.Join(os.TempDir(), username),
+	}
+	u.Permissions = make(map[string][]string)
+	u.Permissions["/"] = []string{"*"}
+	resp, _ := json.Marshal(u)
+	fmt.Printf("%v\n", string(resp))
+	if len(username) > 0 {
+		os.Exit(0)
+	} else {
+		os.Exit(1)
+	}
+}
+
+func main() {
+	// get credentials from env vars
+	username := os.Getenv("SFTPGO_AUTHD_USERNAME")
+	password := os.Getenv("SFTPGO_AUTHD_PASSWORD")
+	if len(password) == 0 {
+		// login method is not password
+		printResponse("")
+		return
+	}
+
+	for _, m := range mapping {
+		if m.SFTPGoUsername == username {
+			// mapping found we can now verify the token
+			url := fmt.Sprintf("https://api.authy.com/protected/json/verify/%v/%v", password, m.AuthyID)
+			req, err := http.NewRequest(http.MethodGet, url, nil)
+			if err != nil {
+				log.Fatal(err)
+			}
+			req.Header.Set("X-Authy-API-Key", m.AuthyAPIKey)
+			httpClient := &http.Client{
+				Timeout: 10 * time.Second,
+			}
+			resp, err := httpClient.Do(req)
+			if err != nil {
+				printResponse("")
+			}
+			defer resp.Body.Close()
+			if resp.StatusCode != http.StatusOK {
+				// status code 200 is expected
+				printResponse("")
+			}
+			var authyResponse map[string]interface{}
+			respBody, err := ioutil.ReadAll(resp.Body)
+			if err != nil {
+				printResponse("")
+			}
+			err = json.Unmarshal(respBody, &authyResponse)
+			if err != nil {
+				printResponse("")
+			}
+			if authyResponse["success"].(string) == "true" {
+				printResponse(username)
+			}
+			printResponse("")
+			break
+		}
+	}
+
+	// no mapping found
+	printResponse("")
+}

examples/OTP/authy/keyint/README.md

@@ -0,0 +1,3 @@
+# Authy 2FA using keyboard interactive authentication
+
+This example shows how to authenticate SFTP users using 2FA (password + Authy token). Please read the [sample code](./main.go), it should be self explanatory.

examples/OTP/authy/keyint/go.mod

@@ -0,0 +1,3 @@
+module github.com/drakkan/sftpgo/authy/keyint
+
+go 1.15

examples/OTP/authy/keyint/main.go

@@ -0,0 +1,137 @@
+package main
+
+import (
+	"bufio"
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"os"
+	"time"
+)
+
+type userMapping struct {
+	SFTPGoUsername string
+	AuthyID        int64
+	AuthyAPIKey    string
+}
+
+type keyboardAuthHookResponse struct {
+	Instruction string   `json:"instruction,omitempty"`
+	Questions   []string `json:"questions,omitempty"`
+	Echos       []bool   `json:"echos,omitempty"`
+	AuthResult  int      `json:"auth_result"`
+	CheckPwd    int      `json:"check_password,omitempty"`
+}
+
+var (
+	mapping []userMapping
+)
+
+func init() {
+	// this is for demo only, you probably want to get this mapping dynamically, for example using a database query
+	mapping = append(mapping, userMapping{
+		SFTPGoUsername: "<SFTPGo username>",
+		AuthyID:        1234567,
+		AuthyAPIKey:    "<your api key>",
+	})
+}
+
+func printAuthResponse(result int) {
+	resp, _ := json.Marshal(keyboardAuthHookResponse{
+		AuthResult: result,
+	})
+	fmt.Printf("%v\n", string(resp))
+	if result == 1 {
+		os.Exit(0)
+	} else {
+		os.Exit(1)
+	}
+}
+
+func main() {
+	// get credentials from env vars
+	username := os.Getenv("SFTPGO_AUTHD_USERNAME")
+	var userMap userMapping
+	for _, m := range mapping {
+		if m.SFTPGoUsername == username {
+			userMap = m
+			break
+		}
+	}
+
+	if userMap.SFTPGoUsername != username {
+		// no mapping found
+		os.Exit(1)
+	}
+
+	checkPwdQuestion := keyboardAuthHookResponse{
+		Instruction: "This is a sample keyboard authentication program that ask for your password + Authy token",
+		Questions:   []string{"Your password: "},
+		Echos:       []bool{false},
+		CheckPwd:    1,
+		AuthResult:  0,
+	}
+
+	q, _ := json.Marshal(checkPwdQuestion)
+	fmt.Printf("%v\n", string(q))
+
+	// in a real world app you probably want to use a read timeout
+	scanner := bufio.NewScanner(os.Stdin)
+	scanner.Scan()
+	if scanner.Err() != nil {
+		printAuthResponse(-1)
+	}
+	response := scanner.Text()
+	if response != "OK" {
+		printAuthResponse(-1)
+	}
+
+	checkTokenQuestion := keyboardAuthHookResponse{
+		Instruction: "",
+		Questions:   []string{"Authy token: "},
+		Echos:       []bool{false},
+		CheckPwd:    0,
+		AuthResult:  0,
+	}
+
+	q, _ = json.Marshal(checkTokenQuestion)
+	fmt.Printf("%v\n", string(q))
+	scanner.Scan()
+	if scanner.Err() != nil {
+		printAuthResponse(-1)
+	}
+	authyToken := scanner.Text()
+
+	url := fmt.Sprintf("https://api.authy.com/protected/json/verify/%v/%v", authyToken, userMap.AuthyID)
+	req, err := http.NewRequest(http.MethodGet, url, nil)
+	if err != nil {
+		printAuthResponse(-1)
+	}
+	req.Header.Set("X-Authy-API-Key", userMap.AuthyAPIKey)
+	httpClient := &http.Client{
+		Timeout: 10 * time.Second,
+	}
+	resp, err := httpClient.Do(req)
+	if err != nil {
+		printAuthResponse(-1)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		// status code 200 is expected
+		printAuthResponse(-1)
+	}
+	var authyResponse map[string]interface{}
+	respBody, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		printAuthResponse(-1)
+	}
+	err = json.Unmarshal(respBody, &authyResponse)
+	if err != nil {
+		printAuthResponse(-1)
+	}
+	if authyResponse["success"].(string) == "true" {
+		printAuthResponse(1)
+	}
+	printAuthResponse(-1)
+}

examples/ldapauth/README.md

@@ -0,0 +1,48 @@
+# LDAPAuth
+
+This is an example for an external authentication program. It performs authentication against an LDAP server.
+It is tested against [389ds](https://directory.fedoraproject.org/) and can be used as starting point to authenticate using any LDAP server including Active Directory.
+
+You need to change the LDAP connection parameters and the user search query to match your environment.
+You can build this example using the following command:
+
+```console
+go build -ldflags "-s -w" -o ldapauth
+```
+
+This program assumes that the 389ds schema was extended to add support for public keys using the following ldif file placed in `/etc/dirsrv/schema/98openssh-ldap.ldif`:
+
+```console
+dn: cn=schema
+changetype: modify
+add: attributetypes
+attributetypes: ( 1.3.6.1.4.1.24552.500.1.1.1.13 NAME 'sshPublicKey' DESC 'MANDATORY: OpenSSH Public key' EQUALITY octetStringMatch SYNTAX 1.3.6.1.4.1.1466.115.121.1.40 )
+-
+add: objectclasses
+objectClasses: ( 1.3.6.1.4.1.24552.500.1.1.2.0 NAME 'ldapPublicKey' SUP top AUXILIARY DESC 'MANDATORY: OpenSSH LPK objectclass' MUST ( uid ) MAY ( sshPublicKey ) )
+-
+
+dn: cn=sshpublickey,cn=default indexes,cn=config,cn=ldbm database,cn=plugins,cn=config
+changetype: add
+cn: sshpublickey
+nsIndexType: eq
+nsIndexType: pres
+nsSystemIndex: false
+objectClass: top
+objectClass: nsIndex
+
+dn: cn=sshpublickey_self_manage,ou=groups,dc=example,dc=com
+changetype: add
+objectClass: top
+objectClass: groupofuniquenames
+cn: sshpublickey_self_manage
+description: Members of this group gain the ability to edit their own sshPublicKey field
+
+dn: dc=example,dc=com
+changetype: modify
+add: aci
+aci: (targetattr = "sshPublicKey") (version 3.0; acl "Allow members of sshpublickey_self_manage to edit their keys"; allow(write) (groupdn = "ldap:///cn=sshpublickey_self_manage,ou=groups,dc=example,dc=com" and userdn="ldap:///self" ); )
+-
+```
+
+Please feel free to send pull requests to improve this example authentication program, thanks!

examples/ldapauth/go.mod

@@ -0,0 +1,9 @@
+module github.com/drakkan/ldapauth
+
+go 1.14
+
+require (
+	github.com/go-ldap/ldap/v3 v3.2.3
+	golang.org/x/crypto v0.0.0-20200709230013-948cd5f35899
+	golang.org/x/sys v0.0.0-20200625212154-ddb9806d33ae // indirect
+)

examples/ldapauth/go.sum

@@ -0,0 +1,15 @@
+github.com/Azure/go-ntlmssp v0.0.0-20200615164410-66371956d46c h1:/IBSNwUN8+eKzUzbJPqhK839ygXJ82sde8x3ogr6R28=
+github.com/Azure/go-ntlmssp v0.0.0-20200615164410-66371956d46c/go.mod h1:chxPXzSsl7ZWRAuOIE23GDNzjWuZquvFlgA8xmpunjU=
+github.com/go-asn1-ber/asn1-ber v1.5.1 h1:pDbRAunXzIUXfx4CB2QJFv5IuPiuoW+sWvr/Us009o8=
+github.com/go-asn1-ber/asn1-ber v1.5.1/go.mod h1:hEBeB/ic+5LoWskz+yKT7vGhhPYkProFKoKdwZRWMe0=
+github.com/go-ldap/ldap/v3 v3.2.3 h1:FBt+5w3q/vPVPb4eYMQSn+pOiz4zewPamYhlGMmc7yM=
+github.com/go-ldap/ldap/v3 v3.2.3/go.mod h1:iYS1MdmrmceOJ1QOTnRXrIs7i3kloqtmGQjRvjKpyMg=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/crypto v0.0.0-20200604202706-70a84ac30bf9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
+golang.org/x/crypto v0.0.0-20200709230013-948cd5f35899 h1:DZhuSZLsGlFL4CmhA8BcRA0mnthyA/nZ00AqCUo7vHg=
+golang.org/x/crypto v0.0.0-20200709230013-948cd5f35899/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
+golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20200625212154-ddb9806d33ae/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=