Added RemoteFileTest

src/test/java/com/hierynomus/sshj/SshFixture.java

@@ -3,15 +3,21 @@ package com.hierynomus.sshj;
 import net.schmizz.sshj.Config;
 import net.schmizz.sshj.DefaultConfig;
 import net.schmizz.sshj.SSHClient;
+import net.schmizz.sshj.transport.TransportException;
+import net.schmizz.sshj.userauth.UserAuthException;
 import net.schmizz.sshj.util.gss.BogusGSSAuthenticator;
 import org.apache.sshd.SshServer;
+import org.apache.sshd.common.NamedFactory;
 import org.apache.sshd.common.keyprovider.FileKeyPairProvider;
+import org.apache.sshd.server.Command;
 import org.apache.sshd.server.PasswordAuthenticator;
 import org.apache.sshd.server.session.ServerSession;
+import org.apache.sshd.server.sftp.SftpSubsystem;
 import org.junit.rules.ExternalResource;
 
 import java.io.IOException;
 import java.net.ServerSocket;
+import java.util.Collections;
 import java.util.concurrent.atomic.AtomicBoolean;
 
 /**
@@ -91,6 +97,7 @@ public class SshFixture extends ExternalResource {
             }
         });
         sshServer.setGSSAuthenticator(new BogusGSSAuthenticator());
+        sshServer.setSubsystemFactories(Collections.<NamedFactory<Command>>singletonList(new SftpSubsystem.Factory()));
         return sshServer;
     }
 

src/test/java/com/hierynomus/sshj/sftp/RemoteFileTest.java

@@ -0,0 +1,75 @@
+package com.hierynomus.sshj.sftp;
+
+import com.hierynomus.sshj.SshFixture;
+import net.schmizz.sshj.SSHClient;
+import net.schmizz.sshj.sftp.OpenMode;
+import net.schmizz.sshj.sftp.RemoteFile;
+import net.schmizz.sshj.sftp.SFTPEngine;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.TemporaryFolder;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.Arrays;
+import java.util.EnumSet;
+import java.util.Random;
+
+import static org.hamcrest.CoreMatchers.equalTo;
+import static org.hamcrest.MatcherAssert.assertThat;
+
+public class RemoteFileTest {
+    @Rule
+    public SshFixture fixture = new SshFixture();
+
+    @Rule
+    public TemporaryFolder temp = new TemporaryFolder();
+
+    @Test
+    public void shouldNotGoOutOfBoundsInReadAheadInputStream() throws IOException {
+        SSHClient ssh = fixture.setupConnectedDefaultClient();
+        ssh.authPassword("test", "test");
+        SFTPEngine sftp = new SFTPEngine(ssh).init();
+
+        RemoteFile rf;
+        File file = temp.newFile("SftpReadAheadTest.bin");
+        rf = sftp.open(file.getPath(), EnumSet.of(OpenMode.WRITE, OpenMode.CREAT));
+        byte[] data = new byte[8192];
+        new Random(53).nextBytes(data);
+        data[3072] = 1;
+        rf.write(0, data, 0, data.length);
+        rf.close();
+
+        assertThat("The file should exist", file.exists());
+
+        rf = sftp.open(file.getPath());
+        InputStream rs = rf.new ReadAheadRemoteFileInputStream(16 /*maxUnconfirmedReads*/);
+
+        byte[] test = new byte[4097];
+        int n = 0;
+
+        while (n < 2048) {
+            n += rs.read(test, n, 2048 - n);
+        }
+
+        while (n < 3072) {
+            n += rs.read(test, n, 3072 - n);
+        }
+
+        if (test[3072] != 0) {
+            System.err.println("buffer overrun!");
+        }
+
+        n += rs.read(test, n, test.length - n); // --> ArrayIndexOutOfBoundsException
+
+        byte[] test2 = new byte[data.length];
+        System.arraycopy(test, 0, test2, 0, test.length);
+
+        while (n < data.length) {
+            n += rs.read(test2, n, data.length - n);
+        }
+
+        assertThat("The written and received data should match", data, equalTo(test2));
+    }
+}