Rename project to sshlib

1 files changed, 1388 insertions, 0 deletions

diff --git a/sshlib/src/main/java/com/trilead/ssh2/SFTPv3Client.java b/sshlib/src/main/java/com/trilead/ssh2/SFTPv3Client.java
new file mode 100644
index 0000000..ce25f07
--- /dev/null
+++ b/sshlib/src/main/java/com/trilead/ssh2/SFTPv3Client.java
@@ -0,0 +1,1388 @@
+
+package com.trilead.ssh2;
+
+import java.io.BufferedOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.io.PrintStream;
+import java.nio.charset.Charset;
+import java.util.HashMap;
+import java.util.Vector;
+
+import com.trilead.ssh2.packets.TypesReader;
+import com.trilead.ssh2.packets.TypesWriter;
+import com.trilead.ssh2.sftp.AttribFlags;
+import com.trilead.ssh2.sftp.ErrorCodes;
+import com.trilead.ssh2.sftp.Packet;
+
+
+/**
+ * A <code>SFTPv3Client</code> represents a SFTP (protocol version 3)
+ * client connection tunnelled over a SSH-2 connection. This is a very simple
+ * (synchronous) implementation.
+ * <p>
+ * Basically, most methods in this class map directly to one of
+ * the packet types described in draft-ietf-secsh-filexfer-02.txt.
+ * <p>
+ * Note: this is experimental code.
+ * <p>
+ * Error handling: the methods of this class throw IOExceptions. However, unless
+ * there is catastrophic failure, exceptions of the type {@link SFTPv3Client} will
+ * be thrown (a subclass of IOException). Therefore, you can implement more verbose
+ * behavior by checking if a thrown exception if of this type. If yes, then you
+ * can cast the exception and access detailed information about the failure. 
+ * <p>
+ * Notes about file names, directory names and paths, copy-pasted
+ * from the specs:
+ * <ul>
+ * <li>SFTP v3 represents file names as strings. File names are
+ * assumed to use the slash ('/') character as a directory separator.</li>
+ * <li>File names starting with a slash are "absolute", and are relative to
+ * the root of the file system.  Names starting with any other character
+ * are relative to the user's default directory (home directory).</li>
+ * <li>Servers SHOULD interpret a path name component ".." as referring to
+ * the parent directory, and "." as referring to the current directory.
+ * If the server implementation limits access to certain parts of the
+ * file system, it must be extra careful in parsing file names when
+ * enforcing such restrictions.  There have been numerous reported
+ * security bugs where a ".." in a path name has allowed access outside
+ * the intended area.</li>
+ * <li>An empty path name is valid, and it refers to the user's default
+ * directory (usually the user's home directory).</li>
+ * </ul>
+ * <p>
+ * If you are still not tired then please go on and read the comment for
+ * {@link #setCharset(String)}.
+ * 
+ * @author Christian Plattner, plattner@trilead.com
+ * @version $Id: SFTPv3Client.java,v 1.3 2008/04/01 12:38:09 cplattne Exp $
+ */
+public class SFTPv3Client
+{
+	final Connection conn;
+	final Session sess;
+	final PrintStream debug;
+
+	boolean flag_closed = false;
+
+	InputStream is;
+	OutputStream os;
+
+	int protocol_version = 0;
+	HashMap server_extensions = new HashMap();
+
+	int next_request_id = 1000;
+
+	String charsetName = null;
+
+	/**
+	 * Create a SFTP v3 client.
+	 * 
+	 * @param conn The underlying SSH-2 connection to be used.
+	 * @param debug
+	 * @throws IOException
+	 * 
+	 * @deprecated this constructor (debug version) will disappear in the future,
+	 *             use {@link #SFTPv3Client(Connection)} instead.
+	 */
+	public SFTPv3Client(Connection conn, PrintStream debug) throws IOException
+	{
+		if (conn == null)
+			throw new IllegalArgumentException("Cannot accept null argument!");
+
+		this.conn = conn;
+		this.debug = debug;
+
+		if (debug != null)
+			debug.println("Opening session and starting SFTP subsystem.");
+
+		sess = conn.openSession();
+		sess.startSubSystem("sftp");
+
+		is = sess.getStdout();
+		os = new BufferedOutputStream(sess.getStdin(), 2048);
+
+		if ((is == null) || (os == null))
+			throw new IOException("There is a problem with the streams of the underlying channel.");
+
+		init();
+	}
+
+	/**
+	 * Create a SFTP v3 client.
+	 * 
+	 * @param conn The underlying SSH-2 connection to be used.
+	 * @throws IOException
+	 */
+	public SFTPv3Client(Connection conn) throws IOException
+	{
+		this(conn, null);
+	}
+
+	/**
+	 * Set the charset used to convert between Java Unicode Strings and byte encodings
+	 * used by the server for paths and file names. Unfortunately, the SFTP v3 draft
+	 * says NOTHING about such conversions (well, with the exception of error messages
+	 * which have to be in UTF-8). Newer drafts specify to use UTF-8 for file names
+	 * (if I remember correctly). However, a quick test using OpenSSH serving a EXT-3
+	 * filesystem has shown that UTF-8 seems to be a bad choice for SFTP v3 (tested with
+	 * filenames containing german umlauts). "windows-1252" seems to work better for Europe.
+	 * Luckily, "windows-1252" is the platform default in my case =).
+	 * <p>
+	 * If you don't set anything, then the platform default will be used (this is the default
+	 * behavior).
+	 * 
+	 * @see #getCharset()
+	 * 
+	 * @param charset the name of the charset to be used or <code>null</code> to use the platform's
+	 *        default encoding.
+	 * @throws IOException
+	 */
+	public void setCharset(String charset) throws IOException
+	{
+		if (charset == null)
+		{
+			charsetName = charset;
+			return;
+		}
+
+		try
+		{
+			Charset.forName(charset);
+		}
+		catch (Exception e)
+		{
+			throw (IOException) new IOException("This charset is not supported").initCause(e);
+		}
+		charsetName = charset;
+	}
+
+	/**
+	 * The currently used charset for filename encoding/decoding.
+	 * 
+	 * @see #setCharset(String)
+	 * 
+	 * @return The name of the charset (<code>null</code> if the platform's default charset is being used)
+	 */
+	public String getCharset()
+	{
+		return charsetName;
+	}
+
+	private final void checkHandleValidAndOpen(SFTPv3FileHandle handle) throws IOException
+	{
+		if (handle.client != this)
+			throw new IOException("The file handle was created with another SFTPv3FileHandle instance.");
+
+		if (handle.isClosed == true)
+			throw new IOException("The file handle is closed.");
+	}
+
+	private final void sendMessage(int type, int requestId, byte[] msg, int off, int len) throws IOException
+	{
+		int msglen = len + 1;
+
+		if (type != Packet.SSH_FXP_INIT)
+			msglen += 4;
+
+		os.write(msglen >> 24);
+		os.write(msglen >> 16);
+		os.write(msglen >> 8);
+		os.write(msglen);
+		os.write(type);
+
+		if (type != Packet.SSH_FXP_INIT)
+		{
+			os.write(requestId >> 24);
+			os.write(requestId >> 16);
+			os.write(requestId >> 8);
+			os.write(requestId);
+		}
+
+		os.write(msg, off, len);
+		os.flush();
+	}
+
+	private final void sendMessage(int type, int requestId, byte[] msg) throws IOException
+	{
+		sendMessage(type, requestId, msg, 0, msg.length);
+	}
+
+	private final void readBytes(byte[] buff, int pos, int len) throws IOException
+	{
+		while (len > 0)
+		{
+			int count = is.read(buff, pos, len);
+			if (count < 0)
+				throw new IOException("Unexpected end of sftp stream.");
+			if ((count == 0) || (count > len))
+				throw new IOException("Underlying stream implementation is bogus!");
+			len -= count;
+			pos += count;
+		}
+	}
+
+	/**
+	 * Read a message and guarantee that the <b>contents</b> is not larger than
+	 * <code>maxlen</code> bytes.
+	 * <p>
+	 * Note: receiveMessage(34000) actually means that the message may be up to 34004
+	 * bytes (the length attribute preceeding the contents is 4 bytes).
+	 * 
+	 * @param maxlen
+	 * @return the message contents
+	 * @throws IOException
+	 */
+	private final byte[] receiveMessage(int maxlen) throws IOException
+	{
+		byte[] msglen = new byte[4];
+
+		readBytes(msglen, 0, 4);
+
+		int len = (((msglen[0] & 0xff) << 24) | ((msglen[1] & 0xff) << 16) | ((msglen[2] & 0xff) << 8) | (msglen[3] & 0xff));
+
+		if ((len > maxlen) || (len <= 0))
+			throw new IOException("Illegal sftp packet len: " + len);
+
+		byte[] msg = new byte[len];
+
+		readBytes(msg, 0, len);
+
+		return msg;
+	}
+
+	private final int generateNextRequestID()
+	{
+		synchronized (this)
+		{
+			return next_request_id++;
+		}
+	}
+
+	private final void closeHandle(byte[] handle) throws IOException
+	{
+		int req_id = generateNextRequestID();
+
+		TypesWriter tw = new TypesWriter();
+		tw.writeString(handle, 0, handle.length);
+
+		sendMessage(Packet.SSH_FXP_CLOSE, req_id, tw.getBytes());
+
+		expectStatusOKMessage(req_id);
+	}
+
+	private SFTPv3FileAttributes readAttrs(TypesReader tr) throws IOException
+	{
+		/*
+		 * uint32   flags
+		 * uint64   size           present only if flag SSH_FILEXFER_ATTR_SIZE
+		 * uint32   uid            present only if flag SSH_FILEXFER_ATTR_V3_UIDGID
+		 * uint32   gid            present only if flag SSH_FILEXFER_ATTR_V3_UIDGID
+		 * uint32   permissions    present only if flag SSH_FILEXFER_ATTR_PERMISSIONS
+		 * uint32   atime          present only if flag SSH_FILEXFER_ATTR_V3_ACMODTIME
+		 * uint32   mtime          present only if flag SSH_FILEXFER_ATTR_V3_ACMODTIME
+		 * uint32   extended_count present only if flag SSH_FILEXFER_ATTR_EXTENDED
+		 * string   extended_type
+		 * string   extended_data
+		 * ...      more extended data (extended_type - extended_data pairs),
+		 *          so that number of pairs equals extended_count
+		 */
+
+		SFTPv3FileAttributes fa = new SFTPv3FileAttributes();
+
+		int flags = tr.readUINT32();
+
+		if ((flags & AttribFlags.SSH_FILEXFER_ATTR_SIZE) != 0)
+		{
+			if (debug != null)
+				debug.println("SSH_FILEXFER_ATTR_SIZE");
+			fa.size = new Long(tr.readUINT64());
+		}
+
+		if ((flags & AttribFlags.SSH_FILEXFER_ATTR_V3_UIDGID) != 0)
+		{
+			if (debug != null)
+				debug.println("SSH_FILEXFER_ATTR_V3_UIDGID");
+			fa.uid = new Integer(tr.readUINT32());
+			fa.gid = new Integer(tr.readUINT32());
+		}
+
+		if ((flags & AttribFlags.SSH_FILEXFER_ATTR_PERMISSIONS) != 0)
+		{
+			if (debug != null)
+				debug.println("SSH_FILEXFER_ATTR_PERMISSIONS");
+			fa.permissions = new Integer(tr.readUINT32());
+		}
+
+		if ((flags & AttribFlags.SSH_FILEXFER_ATTR_V3_ACMODTIME) != 0)
+		{
+			if (debug != null)
+				debug.println("SSH_FILEXFER_ATTR_V3_ACMODTIME");
+			fa.atime = new Long(((long)tr.readUINT32()) & 0xffffffffl);
+			fa.mtime = new Long(((long)tr.readUINT32()) & 0xffffffffl);
+
+		}
+
+		if ((flags & AttribFlags.SSH_FILEXFER_ATTR_EXTENDED) != 0)
+		{
+			int count = tr.readUINT32();
+
+			if (debug != null)
+				debug.println("SSH_FILEXFER_ATTR_EXTENDED (" + count + ")");
+
+			/* Read it anyway to detect corrupt packets */
+
+			while (count > 0)
+			{
+				tr.readByteString();
+				tr.readByteString();
+				count--;
+			}
+		}
+
+		return fa;
+	}
+
+	/**
+	 * Retrieve the file attributes of an open file.
+	 * 
+	 * @param handle a SFTPv3FileHandle handle.
+	 * @return a SFTPv3FileAttributes object.
+	 * @throws IOException
+	 */
+	public SFTPv3FileAttributes fstat(SFTPv3FileHandle handle) throws IOException
+	{
+		checkHandleValidAndOpen(handle);
+
+		int req_id = generateNextRequestID();
+
+		TypesWriter tw = new TypesWriter();
+		tw.writeString(handle.fileHandle, 0, handle.fileHandle.length);
+
+		if (debug != null)
+		{
+			debug.println("Sending SSH_FXP_FSTAT...");
+			debug.flush();
+		}
+
+		sendMessage(Packet.SSH_FXP_FSTAT, req_id, tw.getBytes());
+
+		byte[] resp = receiveMessage(34000);
+
+		if (debug != null)
+		{
+			debug.println("Got REPLY.");
+			debug.flush();
+		}
+
+		TypesReader tr = new TypesReader(resp);
+
+		int t = tr.readByte();
+
+		int rep_id = tr.readUINT32();
+		if (rep_id != req_id)
+			throw new IOException("The server sent an invalid id field.");
+
+		if (t == Packet.SSH_FXP_ATTRS)
+		{
+			return readAttrs(tr);
+		}
+
+		if (t != Packet.SSH_FXP_STATUS)
+			throw new IOException("The SFTP server sent an unexpected packet type (" + t + ")");
+
+		int errorCode = tr.readUINT32();
+
+		throw new SFTPException(tr.readString(), errorCode);
+	}
+
+	private SFTPv3FileAttributes statBoth(String path, int statMethod) throws IOException
+	{
+		int req_id = generateNextRequestID();
+
+		TypesWriter tw = new TypesWriter();
+		tw.writeString(path, charsetName);
+
+		if (debug != null)
+		{
+			debug.println("Sending SSH_FXP_STAT/SSH_FXP_LSTAT...");
+			debug.flush();
+		}
+
+		sendMessage(statMethod, req_id, tw.getBytes());
+
+		byte[] resp = receiveMessage(34000);
+
+		if (debug != null)
+		{
+			debug.println("Got REPLY.");
+			debug.flush();
+		}
+
+		TypesReader tr = new TypesReader(resp);
+
+		int t = tr.readByte();
+
+		int rep_id = tr.readUINT32();
+		if (rep_id != req_id)
+			throw new IOException("The server sent an invalid id field.");
+
+		if (t == Packet.SSH_FXP_ATTRS)
+		{
+			return readAttrs(tr);
+		}
+
+		if (t != Packet.SSH_FXP_STATUS)
+			throw new IOException("The SFTP server sent an unexpected packet type (" + t + ")");
+
+		int errorCode = tr.readUINT32();
+
+		throw new SFTPException(tr.readString(), errorCode);
+	}
+
+	/**
+	 * Retrieve the file attributes of a file. This method
+	 * follows symbolic links on the server.
+	 * 
+	 * @see #lstat(String)
+	 * 
+	 * @param path See the {@link SFTPv3Client comment} for the class for more details.
+	 * @return a SFTPv3FileAttributes object.
+	 * @throws IOException
+	 */
+	public SFTPv3FileAttributes stat(String path) throws IOException
+	{
+		return statBoth(path, Packet.SSH_FXP_STAT);
+	}
+
+	/**
+	 * Retrieve the file attributes of a file. This method
+	 * does NOT follow symbolic links on the server.
+	 * 
+	 * @see #stat(String)
+	 * 
+	 * @param path See the {@link SFTPv3Client comment} for the class for more details.
+	 * @return a SFTPv3FileAttributes object.
+	 * @throws IOException
+	 */
+	public SFTPv3FileAttributes lstat(String path) throws IOException
+	{
+		return statBoth(path, Packet.SSH_FXP_LSTAT);
+	}
+
+	/**
+	 * Read the target of a symbolic link.
+	 * 
+	 * @param path See the {@link SFTPv3Client comment} for the class for more details.
+	 * @return The target of the link.
+	 * @throws IOException
+	 */
+	public String readLink(String path) throws IOException
+	{
+		int req_id = generateNextRequestID();
+
+		TypesWriter tw = new TypesWriter();
+		tw.writeString(path, charsetName);
+
+		if (debug != null)
+		{
+			debug.println("Sending SSH_FXP_READLINK...");
+			debug.flush();
+		}
+
+		sendMessage(Packet.SSH_FXP_READLINK, req_id, tw.getBytes());
+
+		byte[] resp = receiveMessage(34000);
+
+		if (debug != null)
+		{
+			debug.println("Got REPLY.");
+			debug.flush();
+		}
+
+		TypesReader tr = new TypesReader(resp);
+
+		int t = tr.readByte();
+
+		int rep_id = tr.readUINT32();
+		if (rep_id != req_id)
+			throw new IOException("The server sent an invalid id field.");
+
+		if (t == Packet.SSH_FXP_NAME)
+		{
+			int count = tr.readUINT32();
+
+			if (count != 1)
+				throw new IOException("The server sent an invalid SSH_FXP_NAME packet.");
+
+			return tr.readString(charsetName);
+		}
+
+		if (t != Packet.SSH_FXP_STATUS)
+			throw new IOException("The SFTP server sent an unexpected packet type (" + t + ")");
+
+		int errorCode = tr.readUINT32();
+
+		throw new SFTPException(tr.readString(), errorCode);
+	}
+
+	private void expectStatusOKMessage(int id) throws IOException
+	{
+		byte[] resp = receiveMessage(34000);
+
+		if (debug != null)
+		{
+			debug.println("Got REPLY.");
+			debug.flush();
+		}
+
+		TypesReader tr = new TypesReader(resp);
+
+		int t = tr.readByte();
+
+		int rep_id = tr.readUINT32();
+		if (rep_id != id)
+			throw new IOException("The server sent an invalid id field.");
+
+		if (t != Packet.SSH_FXP_STATUS)
+			throw new IOException("The SFTP server sent an unexpected packet type (" + t + ")");
+
+		int errorCode = tr.readUINT32();
+
+		if (errorCode == ErrorCodes.SSH_FX_OK)
+			return;
+
+		throw new SFTPException(tr.readString(), errorCode);
+	}
+
+	/**
+	 *  Modify the attributes of a file. Used for operations such as changing
+	 *  the ownership, permissions or access times, as well as for truncating a file.
+	 * 
+	 * @param path See the {@link SFTPv3Client comment} for the class for more details.
+	 * @param attr A SFTPv3FileAttributes object. Specifies the modifications to be
+	 *             made to the attributes of the file. Empty fields will be ignored.
+	 * @throws IOException
+	 */
+	public void setstat(String path, SFTPv3FileAttributes attr) throws IOException
+	{
+		int req_id = generateNextRequestID();
+
+		TypesWriter tw = new TypesWriter();
+		tw.writeString(path, charsetName);
+		tw.writeBytes(createAttrs(attr));
+
+		if (debug != null)
+		{
+			debug.println("Sending SSH_FXP_SETSTAT...");
+			debug.flush();
+		}
+
+		sendMessage(Packet.SSH_FXP_SETSTAT, req_id, tw.getBytes());
+
+		expectStatusOKMessage(req_id);
+	}
+
+	/**
+	 * 	Modify the attributes of a file. Used for operations such as changing
+	 *  the ownership, permissions or access times, as well as for truncating a file.
+	 * 
+	 * @param handle a SFTPv3FileHandle handle
+	 * @param attr A SFTPv3FileAttributes object. Specifies the modifications to be
+	 *             made to the attributes of the file. Empty fields will be ignored.
+	 * @throws IOException
+	 */
+	public void fsetstat(SFTPv3FileHandle handle, SFTPv3FileAttributes attr) throws IOException
+	{
+		checkHandleValidAndOpen(handle);
+
+		int req_id = generateNextRequestID();
+
+		TypesWriter tw = new TypesWriter();
+		tw.writeString(handle.fileHandle, 0, handle.fileHandle.length);
+		tw.writeBytes(createAttrs(attr));
+
+		if (debug != null)
+		{
+			debug.println("Sending SSH_FXP_FSETSTAT...");
+			debug.flush();
+		}
+
+		sendMessage(Packet.SSH_FXP_FSETSTAT, req_id, tw.getBytes());
+
+		expectStatusOKMessage(req_id);
+	}
+
+	/**
+	 * Create a symbolic link on the server. Creates a link "src" that points
+	 * to "target".
+	 * 
+	 * @param src See the {@link SFTPv3Client comment} for the class for more details.
+	 * @param target See the {@link SFTPv3Client comment} for the class for more details.
+	 * @throws IOException
+	 */
+	public void createSymlink(String src, String target) throws IOException
+	{
+		int req_id = generateNextRequestID();
+
+		/* Either I am too stupid to understand the SFTP draft
+		 * or the OpenSSH guys changed the semantics of src and target.
+		 */
+
+		TypesWriter tw = new TypesWriter();
+		tw.writeString(target, charsetName);
+		tw.writeString(src, charsetName);
+
+		if (debug != null)
+		{
+			debug.println("Sending SSH_FXP_SYMLINK...");
+			debug.flush();
+		}
+
+		sendMessage(Packet.SSH_FXP_SYMLINK, req_id, tw.getBytes());
+
+		expectStatusOKMessage(req_id);
+	}
+
+	/**
+	 * Have the server canonicalize any given path name to an absolute path.
+	 * This is useful for converting path names containing ".." components or
+	 * relative pathnames without a leading slash into absolute paths.
+	 * 
+	 * @param path See the {@link SFTPv3Client comment} for the class for more details.
+	 * @return An absolute path.
+	 * @throws IOException
+	 */
+	public String canonicalPath(String path) throws IOException
+	{
+		int req_id = generateNextRequestID();
+
+		TypesWriter tw = new TypesWriter();
+		tw.writeString(path, charsetName);
+
+		if (debug != null)
+		{
+			debug.println("Sending SSH_FXP_REALPATH...");
+			debug.flush();
+		}
+
+		sendMessage(Packet.SSH_FXP_REALPATH, req_id, tw.getBytes());
+
+		byte[] resp = receiveMessage(34000);
+
+		if (debug != null)
+		{
+			debug.println("Got REPLY.");
+			debug.flush();
+		}
+
+		TypesReader tr = new TypesReader(resp);
+
+		int t = tr.readByte();
+
+		int rep_id = tr.readUINT32();
+		if (rep_id != req_id)
+			throw new IOException("The server sent an invalid id field.");
+
+		if (t == Packet.SSH_FXP_NAME)
+		{
+			int count = tr.readUINT32();
+
+			if (count != 1)
+				throw new IOException("The server sent an invalid SSH_FXP_NAME packet.");
+
+			return tr.readString(charsetName);
+		}
+
+		if (t != Packet.SSH_FXP_STATUS)
+			throw new IOException("The SFTP server sent an unexpected packet type (" + t + ")");
+
+		int errorCode = tr.readUINT32();
+
+		throw new SFTPException(tr.readString(), errorCode);
+	}
+
+	private final Vector scanDirectory(byte[] handle) throws IOException
+	{
+		Vector files = new Vector();
+
+		while (true)
+		{
+			int req_id = generateNextRequestID();
+
+			TypesWriter tw = new TypesWriter();
+			tw.writeString(handle, 0, handle.length);
+
+			if (debug != null)
+			{
+				debug.println("Sending SSH_FXP_READDIR...");
+				debug.flush();
+			}
+
+			sendMessage(Packet.SSH_FXP_READDIR, req_id, tw.getBytes());
+		
+			/* Some servers send here a packet with size > 34000 */
+			/* To whom it may concern: please learn to read the specs. */
+			
+			byte[] resp = receiveMessage(65536);
+
+			if (debug != null)
+			{
+				debug.println("Got REPLY.");
+				debug.flush();
+			}
+
+			TypesReader tr = new TypesReader(resp);
+
+			int t = tr.readByte();
+
+			int rep_id = tr.readUINT32();
+			if (rep_id != req_id)
+				throw new IOException("The server sent an invalid id field.");
+
+			if (t == Packet.SSH_FXP_NAME)
+			{
+				int count = tr.readUINT32();
+
+				if (debug != null)
+					debug.println("Parsing " + count + " name entries...");
+
+				while (count > 0)
+				{
+					SFTPv3DirectoryEntry dirEnt = new SFTPv3DirectoryEntry();
+
+					dirEnt.filename = tr.readString(charsetName);
+					dirEnt.longEntry = tr.readString(charsetName);
+
+					dirEnt.attributes = readAttrs(tr);
+					files.addElement(dirEnt);
+
+					if (debug != null)
+						debug.println("File: '" + dirEnt.filename + "'");
+					count--;
+				}
+				continue;
+			}
+
+			if (t != Packet.SSH_FXP_STATUS)
+				throw new IOException("The SFTP server sent an unexpected packet type (" + t + ")");
+
+			int errorCode = tr.readUINT32();
+
+			if (errorCode == ErrorCodes.SSH_FX_EOF)
+				return files;
+
+			throw new SFTPException(tr.readString(), errorCode);
+		}
+	}
+
+	private final byte[] openDirectory(String path) throws IOException
+	{
+		int req_id = generateNextRequestID();
+
+		TypesWriter tw = new TypesWriter();
+		tw.writeString(path, charsetName);
+
+		if (debug != null)
+		{
+			debug.println("Sending SSH_FXP_OPENDIR...");
+			debug.flush();
+		}
+
+		sendMessage(Packet.SSH_FXP_OPENDIR, req_id, tw.getBytes());
+
+		byte[] resp = receiveMessage(34000);
+
+		TypesReader tr = new TypesReader(resp);
+
+		int t = tr.readByte();
+
+		int rep_id = tr.readUINT32();
+		if (rep_id != req_id)
+			throw new IOException("The server sent an invalid id field.");
+
+		if (t == Packet.SSH_FXP_HANDLE)
+		{
+			if (debug != null)
+			{
+				debug.println("Got SSH_FXP_HANDLE.");
+				debug.flush();
+			}
+
+			byte[] handle = tr.readByteString();
+			return handle;
+		}
+
+		if (t != Packet.SSH_FXP_STATUS)
+			throw new IOException("The SFTP server sent an unexpected packet type (" + t + ")");
+
+		int errorCode = tr.readUINT32();
+		String errorMessage = tr.readString();
+
+		throw new SFTPException(errorMessage, errorCode);
+	}
+
+	private final String expandString(byte[] b, int off, int len)
+	{
+		StringBuffer sb = new StringBuffer();
+
+		for (int i = 0; i < len; i++)
+		{
+			int c = b[off + i] & 0xff;
+
+			if ((c >= 32) && (c <= 126))
+			{
+				sb.append((char) c);
+			}
+			else
+			{
+				sb.append("{0x" + Integer.toHexString(c) + "}");
+			}
+		}
+
+		return sb.toString();
+	}
+
+	private void init() throws IOException
+	{
+		/* Send SSH_FXP_INIT (version 3) */
+
+		final int client_version = 3;
+
+		if (debug != null)
+			debug.println("Sending SSH_FXP_INIT (" + client_version + ")...");
+
+		TypesWriter tw = new TypesWriter();
+		tw.writeUINT32(client_version);
+		sendMessage(Packet.SSH_FXP_INIT, 0, tw.getBytes());
+
+		/* Receive SSH_FXP_VERSION */
+
+		if (debug != null)
+			debug.println("Waiting for SSH_FXP_VERSION...");
+
+		TypesReader tr = new TypesReader(receiveMessage(34000)); /* Should be enough for any reasonable server */
+
+		int type = tr.readByte();
+
+		if (type != Packet.SSH_FXP_VERSION)
+		{
+			throw new IOException("The server did not send a SSH_FXP_VERSION packet (got " + type + ")");
+		}
+
+		protocol_version = tr.readUINT32();
+
+		if (debug != null)
+			debug.println("SSH_FXP_VERSION: protocol_version = " + protocol_version);
+
+		if (protocol_version != 3)
+			throw new IOException("Server version " + protocol_version + " is currently not supported");
+
+		/* Read and save extensions (if any) for later use */
+
+		while (tr.remain() != 0)
+		{
+			String name = tr.readString();
+			byte[] value = tr.readByteString();
+			server_extensions.put(name, value);
+
+			if (debug != null)
+				debug.println("SSH_FXP_VERSION: extension: " + name + " = '" + expandString(value, 0, value.length)
+						+ "'");
+		}
+	}
+
+	/**
+	 * Returns the negotiated SFTP protocol version between the client and the server.
+	 * 
+	 * @return SFTP protocol version, i.e., "3".
+	 * 
+	 */
+	public int getProtocolVersion()
+	{
+		return protocol_version;
+	}
+
+	/**
+	 * Close this SFTP session. NEVER forget to call this method to free up
+	 * resources - even if you got an exception from one of the other methods.
+	 * Sometimes these other methods may throw an exception, saying that the
+	 * underlying channel is closed (this can happen, e.g., if the other server
+	 * sent a close message.) However, as long as you have not called the
+	 * <code>close()</code> method, you are likely wasting resources.
+	 * 
+	 */
+	public void close()
+	{
+		sess.close();
+	}
+
+	/**
+	 * List the contents of a directory.
+	 * 
+	 * @param dirName See the {@link SFTPv3Client comment} for the class for more details.
+	 * @return A Vector containing {@link SFTPv3DirectoryEntry} objects.
+	 * @throws IOException
+	 */
+	public Vector ls(String dirName) throws IOException
+	{
+		byte[] handle = openDirectory(dirName);
+		Vector result = scanDirectory(handle);
+		closeHandle(handle);
+		return result;
+	}
+
+	/**
+	 * Create a new directory.
+	 * 
+	 * @param dirName See the {@link SFTPv3Client comment} for the class for more details.
+	 * @param posixPermissions the permissions for this directory, e.g., "0700" (remember that
+	 *                         this is octal noation). The server will likely apply a umask.
+	 * 
+	 * @throws IOException
+	 */
+	public void mkdir(String dirName, int posixPermissions) throws IOException
+	{
+		int req_id = generateNextRequestID();
+
+		TypesWriter tw = new TypesWriter();
+		tw.writeString(dirName, charsetName);
+		tw.writeUINT32(AttribFlags.SSH_FILEXFER_ATTR_PERMISSIONS);
+		tw.writeUINT32(posixPermissions);
+
+		sendMessage(Packet.SSH_FXP_MKDIR, req_id, tw.getBytes());
+
+		expectStatusOKMessage(req_id);
+	}
+
+	/**
+	 * Remove a file.
+	 * 
+	 * @param fileName See the {@link SFTPv3Client comment} for the class for more details.
+	 * @throws IOException
+	 */
+	public void rm(String fileName) throws IOException
+	{
+		int req_id = generateNextRequestID();
+
+		TypesWriter tw = new TypesWriter();
+		tw.writeString(fileName, charsetName);
+
+		sendMessage(Packet.SSH_FXP_REMOVE, req_id, tw.getBytes());
+
+		expectStatusOKMessage(req_id);
+	}
+
+	/**
+	 * Remove an empty directory. 
+	 * 
+	 * @param dirName See the {@link SFTPv3Client comment} for the class for more details.
+	 * @throws IOException
+	 */
+	public void rmdir(String dirName) throws IOException
+	{
+		int req_id = generateNextRequestID();
+
+		TypesWriter tw = new TypesWriter();
+		tw.writeString(dirName, charsetName);
+
+		sendMessage(Packet.SSH_FXP_RMDIR, req_id, tw.getBytes());
+
+		expectStatusOKMessage(req_id);
+	}
+
+	/**
+	 * Move a file or directory.
+	 * 
+	 * @param oldPath See the {@link SFTPv3Client comment} for the class for more details.
+	 * @param newPath See the {@link SFTPv3Client comment} for the class for more details.
+	 * @throws IOException
+	 */
+	public void mv(String oldPath, String newPath) throws IOException
+	{
+		int req_id = generateNextRequestID();
+
+		TypesWriter tw = new TypesWriter();
+		tw.writeString(oldPath, charsetName);
+		tw.writeString(newPath, charsetName);
+
+		sendMessage(Packet.SSH_FXP_RENAME, req_id, tw.getBytes());
+
+		expectStatusOKMessage(req_id);
+	}
+
+	/**
+	 * Open a file for reading.
+	 * 
+	 * @param fileName See the {@link SFTPv3Client comment} for the class for more details.
+	 * @return a SFTPv3FileHandle handle
+	 * @throws IOException
+	 */
+	public SFTPv3FileHandle openFileRO(String fileName) throws IOException
+	{
+		return openFile(fileName, 0x00000001, null); // SSH_FXF_READ	
+	}
+
+	/**
+	 * Open a file for reading and writing.
+	 * 
+	 * @param fileName See the {@link SFTPv3Client comment} for the class for more details.
+	 * @return a SFTPv3FileHandle handle
+	 * @throws IOException
+	 */
+	public SFTPv3FileHandle openFileRW(String fileName) throws IOException
+	{
+		return openFile(fileName, 0x00000003, null); // SSH_FXF_READ | SSH_FXF_WRITE
+	}
+
+	// Append is broken (already in the specification, because there is no way to
+	// send a write operation (what offset to use??))
+	//	public SFTPv3FileHandle openFileRWAppend(String fileName) throws IOException
+	//	{
+	//		return openFile(fileName, 0x00000007, null); // SSH_FXF_READ | SSH_FXF_WRITE | SSH_FXF_APPEND
+	//	}
+
+	/**
+	 * Create a file and open it for reading and writing.
+	 * Same as {@link #createFile(String, SFTPv3FileAttributes) createFile(fileName, null)}.
+	 * 
+	 * @param fileName See the {@link SFTPv3Client comment} for the class for more details.
+	 * @return a SFTPv3FileHandle handle
+	 * @throws IOException
+	 */
+	public SFTPv3FileHandle createFile(String fileName) throws IOException
+	{
+		return createFile(fileName, null);
+	}
+
+	/**
+	 * Create a file and open it for reading and writing.
+	 * You can specify the default attributes of the file (the server may or may
+	 * not respect your wishes).
+	 * 
+	 * @param fileName See the {@link SFTPv3Client comment} for the class for more details.
+	 * @param attr may be <code>null</code> to use server defaults. Probably only
+	 *             the <code>uid</code>, <code>gid</code> and <code>permissions</code>
+	 *             (remember the server may apply a umask) entries of the {@link SFTPv3FileHandle}
+	 *             structure make sense. You need only to set those fields where you want
+	 *             to override the server's defaults.
+	 * @return a SFTPv3FileHandle handle
+	 * @throws IOException
+	 */
+	public SFTPv3FileHandle createFile(String fileName, SFTPv3FileAttributes attr) throws IOException
+	{
+		return openFile(fileName, 0x00000008 | 0x00000003, attr); // SSH_FXF_CREAT | SSH_FXF_READ | SSH_FXF_WRITE
+	}
+
+	/**
+	 * Create a file (truncate it if it already exists) and open it for reading and writing.
+	 * Same as {@link #createFileTruncate(String, SFTPv3FileAttributes) createFileTruncate(fileName, null)}.
+	 * 
+	 * @param fileName See the {@link SFTPv3Client comment} for the class for more details.
+	 * @return a SFTPv3FileHandle handle
+	 * @throws IOException
+	 */
+	public SFTPv3FileHandle createFileTruncate(String fileName) throws IOException
+	{
+		return createFileTruncate(fileName, null);
+	}
+
+	/**
+	 * reate a file (truncate it if it already exists) and open it for reading and writing.
+	 * You can specify the default attributes of the file (the server may or may
+	 * not respect your wishes).
+	 * 
+	 * @param fileName See the {@link SFTPv3Client comment} for the class for more details.
+	 * @param attr may be <code>null</code> to use server defaults. Probably only
+	 *             the <code>uid</code>, <code>gid</code> and <code>permissions</code>
+	 *             (remember the server may apply a umask) entries of the {@link SFTPv3FileHandle}
+	 *             structure make sense. You need only to set those fields where you want
+	 *             to override the server's defaults.
+	 * @return a SFTPv3FileHandle handle
+	 * @throws IOException
+	 */
+	public SFTPv3FileHandle createFileTruncate(String fileName, SFTPv3FileAttributes attr) throws IOException
+	{
+		return openFile(fileName, 0x00000018 | 0x00000003, attr); // SSH_FXF_CREAT | SSH_FXF_TRUNC | SSH_FXF_READ | SSH_FXF_WRITE
+	}
+
+	private byte[] createAttrs(SFTPv3FileAttributes attr)
+	{
+		TypesWriter tw = new TypesWriter();
+
+		int attrFlags = 0;
+
+		if (attr == null)
+		{
+			tw.writeUINT32(0);
+		}
+		else
+		{
+			if (attr.size != null)
+				attrFlags = attrFlags | AttribFlags.SSH_FILEXFER_ATTR_SIZE;
+
+			if ((attr.uid != null) && (attr.gid != null))
+				attrFlags = attrFlags | AttribFlags.SSH_FILEXFER_ATTR_V3_UIDGID;
+
+			if (attr.permissions != null)
+				attrFlags = attrFlags | AttribFlags.SSH_FILEXFER_ATTR_PERMISSIONS;
+
+			if ((attr.atime != null) && (attr.mtime != null))
+				attrFlags = attrFlags | AttribFlags.SSH_FILEXFER_ATTR_V3_ACMODTIME;
+
+			tw.writeUINT32(attrFlags);
+
+			if (attr.size != null)
+				tw.writeUINT64(attr.size.longValue());
+
+			if ((attr.uid != null) && (attr.gid != null))
+			{
+				tw.writeUINT32(attr.uid.intValue());
+				tw.writeUINT32(attr.gid.intValue());
+			}
+
+			if (attr.permissions != null)
+				tw.writeUINT32(attr.permissions.intValue());
+
+			if ((attr.atime != null) && (attr.mtime != null))
+			{
+				tw.writeUINT32(attr.atime.intValue());
+				tw.writeUINT32(attr.mtime.intValue());
+			}
+		}
+
+		return tw.getBytes();
+	}
+
+	private SFTPv3FileHandle openFile(String fileName, int flags, SFTPv3FileAttributes attr) throws IOException
+	{
+		int req_id = generateNextRequestID();
+
+		TypesWriter tw = new TypesWriter();
+		tw.writeString(fileName, charsetName);
+		tw.writeUINT32(flags);
+		tw.writeBytes(createAttrs(attr));
+
+		if (debug != null)
+		{
+			debug.println("Sending SSH_FXP_OPEN...");
+			debug.flush();
+		}
+
+		sendMessage(Packet.SSH_FXP_OPEN, req_id, tw.getBytes());
+
+		byte[] resp = receiveMessage(34000);
+
+		TypesReader tr = new TypesReader(resp);
+
+		int t = tr.readByte();
+
+		int rep_id = tr.readUINT32();
+		if (rep_id != req_id)
+			throw new IOException("The server sent an invalid id field.");
+
+		if (t == Packet.SSH_FXP_HANDLE)
+		{
+			if (debug != null)
+			{
+				debug.println("Got SSH_FXP_HANDLE.");
+				debug.flush();
+			}
+
+			return new SFTPv3FileHandle(this, tr.readByteString());
+		}
+
+		if (t != Packet.SSH_FXP_STATUS)
+			throw new IOException("The SFTP server sent an unexpected packet type (" + t + ")");
+
+		int errorCode = tr.readUINT32();
+		String errorMessage = tr.readString();
+
+		throw new SFTPException(errorMessage, errorCode);
+	}
+
+	/**
+	 * Read bytes from a file. No more than 32768 bytes may be read at once.
+	 * Be aware that the semantics of read() are different than for Java streams.
+	 * <p>
+	 * <ul>
+	 * <li>The server will read as many bytes as it can from the file (up to <code>len</code>),
+	 * and return them.</li>
+	 * <li>If EOF is encountered before reading any data, <code>-1</code> is returned.</li>
+	 * <li>If an error occurs, an exception is thrown.</li>
+	 * <li>For normal disk files, it is guaranteed that the server will return the specified
+	 * number of bytes, or up to end of file. For, e.g., device files this may return
+	 * fewer bytes than requested.</li>
+	 * </ul>
+	 * 
+	 * @param handle a SFTPv3FileHandle handle
+	 * @param fileOffset offset (in bytes) in the file
+	 * @param dst the destination byte array
+	 * @param dstoff offset in the destination byte array
+	 * @param len how many bytes to read, 0 &lt; len &lt;= 32768 bytes
+	 * @return the number of bytes that could be read, may be less than requested if
+	 *         the end of the file is reached, -1 is returned in case of <code>EOF</code>
+	 * @throws IOException
+	 */
+	public int read(SFTPv3FileHandle handle, long fileOffset, byte[] dst, int dstoff, int len) throws IOException
+	{
+		checkHandleValidAndOpen(handle);
+
+		if ((len > 32768) || (len <= 0))
+			throw new IllegalArgumentException("invalid len argument");
+
+		int req_id = generateNextRequestID();
+
+		TypesWriter tw = new TypesWriter();
+		tw.writeString(handle.fileHandle, 0, handle.fileHandle.length);
+		tw.writeUINT64(fileOffset);
+		tw.writeUINT32(len);
+
+		if (debug != null)
+		{
+			debug.println("Sending SSH_FXP_READ...");
+			debug.flush();
+		}
+
+		sendMessage(Packet.SSH_FXP_READ, req_id, tw.getBytes());
+
+		byte[] resp = receiveMessage(34000);
+
+		TypesReader tr = new TypesReader(resp);
+
+		int t = tr.readByte();
+
+		int rep_id = tr.readUINT32();
+		if (rep_id != req_id)
+			throw new IOException("The server sent an invalid id field.");
+
+		if (t == Packet.SSH_FXP_DATA)
+		{
+			if (debug != null)
+			{
+				debug.println("Got SSH_FXP_DATA...");
+				debug.flush();
+			}
+
+			int readLen = tr.readUINT32();
+
+			if ((readLen < 0) || (readLen > len))
+				throw new IOException("The server sent an invalid length field.");
+
+			tr.readBytes(dst, dstoff, readLen);
+
+			return readLen;
+		}
+
+		if (t != Packet.SSH_FXP_STATUS)
+			throw new IOException("The SFTP server sent an unexpected packet type (" + t + ")");
+
+		int errorCode = tr.readUINT32();
+
+		if (errorCode == ErrorCodes.SSH_FX_EOF)
+		{
+			if (debug != null)
+			{
+				debug.println("Got SSH_FX_EOF.");
+				debug.flush();
+			}
+
+			return -1;
+		}
+
+		String errorMessage = tr.readString();
+
+		throw new SFTPException(errorMessage, errorCode);
+	}
+
+	/**
+	 * Write bytes to a file. If <code>len</code> &gt; 32768, then the write operation will
+	 * be split into multiple writes.
+	 * 
+	 * @param handle a SFTPv3FileHandle handle.
+	 * @param fileOffset offset (in bytes) in the file.
+	 * @param src the source byte array.
+	 * @param srcoff offset in the source byte array.
+	 * @param len how many bytes to write.
+	 * @throws IOException
+	 */
+	public void write(SFTPv3FileHandle handle, long fileOffset, byte[] src, int srcoff, int len) throws IOException
+	{
+		checkHandleValidAndOpen(handle);
+
+		while (len > 0)
+		{
+			int writeRequestLen = len;
+
+			if (writeRequestLen > 32768)
+				writeRequestLen = 32768;
+
+			int req_id = generateNextRequestID();
+
+			TypesWriter tw = new TypesWriter();
+			tw.writeString(handle.fileHandle, 0, handle.fileHandle.length);
+			tw.writeUINT64(fileOffset);
+			tw.writeString(src, srcoff, writeRequestLen);
+
+			if (debug != null)
+			{
+				debug.println("Sending SSH_FXP_WRITE...");
+				debug.flush();
+			}
+
+			sendMessage(Packet.SSH_FXP_WRITE, req_id, tw.getBytes());
+
+			fileOffset += writeRequestLen;
+
+			srcoff += writeRequestLen;
+			len -= writeRequestLen;
+
+			byte[] resp = receiveMessage(34000);
+
+			TypesReader tr = new TypesReader(resp);
+
+			int t = tr.readByte();
+
+			int rep_id = tr.readUINT32();
+			if (rep_id != req_id)
+				throw new IOException("The server sent an invalid id field.");
+
+			if (t != Packet.SSH_FXP_STATUS)
+				throw new IOException("The SFTP server sent an unexpected packet type (" + t + ")");
+
+			int errorCode = tr.readUINT32();
+
+			if (errorCode == ErrorCodes.SSH_FX_OK)
+				continue;
+
+			String errorMessage = tr.readString();
+
+			throw new SFTPException(errorMessage, errorCode);
+		}
+	}
+
+	/**
+	 * Close a file.
+	 * 
+	 * @param handle a SFTPv3FileHandle handle
+	 * @throws IOException
+	 */
+	public void closeFile(SFTPv3FileHandle handle) throws IOException
+	{
+		if (handle == null)
+			throw new IllegalArgumentException("the handle argument may not be null");
+
+		try
+		{
+			if (handle.isClosed == false)
+			{
+				closeHandle(handle.fileHandle);
+			}
+		}
+		finally
+		{
+			handle.isClosed = true;
+		}
+	}
+}