diff src/ch/ethz/ssh2/channel/ChannelManager.java @ 273:91a31873c42a ganymed

start conversion from trilead to ganymed
author Carl Byington <carl@five-ten-sg.com>
date Fri, 18 Jul 2014 11:21:46 -0700
parents
children 5824a1475be4
line wrap: on
line diff
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/ch/ethz/ssh2/channel/ChannelManager.java	Fri Jul 18 11:21:46 2014 -0700
@@ -0,0 +1,1644 @@
+/*
+ * Copyright (c) 2006-2013 Christian Plattner. All rights reserved.
+ * Please refer to the LICENSE.txt for licensing details.
+ */
+
+package ch.ethz.ssh2.channel;
+
+import java.io.IOException;
+import java.io.InterruptedIOException;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import ch.ethz.ssh2.ChannelCondition;
+import ch.ethz.ssh2.PacketFormatException;
+import ch.ethz.ssh2.PacketTypeException;
+import ch.ethz.ssh2.PtySettings;
+import ch.ethz.ssh2.ServerConnectionCallback;
+import ch.ethz.ssh2.ServerSessionCallback;
+import ch.ethz.ssh2.log.Logger;
+import ch.ethz.ssh2.packets.*;
+import ch.ethz.ssh2.server.ServerConnectionState;
+import ch.ethz.ssh2.transport.MessageHandler;
+import ch.ethz.ssh2.transport.TransportManager;
+
+/**
+ * ChannelManager. Please read the comments in Channel.java.
+ * <p/>
+ * Besides the crypto part, this is the core of the library.
+ *
+ * @author Christian Plattner
+ * @version $Id: ChannelManager.java 160 2014-05-01 14:30:26Z dkocher@sudo.ch $
+ */
+public class ChannelManager implements MessageHandler {
+    private static final Logger log = Logger.getLogger(ChannelManager.class);
+
+    private final ServerConnectionState server_state;
+    private final TransportManager tm;
+
+    private final Map<String, X11ServerData> x11_magic_cookies = new HashMap<String, X11ServerData>();
+
+    private final List<Channel> channels = new ArrayList<Channel>();
+    private int nextLocalChannel = 100;
+    private boolean shutdown = false;
+    private int globalSuccessCounter = 0;
+    private int globalFailedCounter = 0;
+
+    private final Map<Integer, RemoteForwardingData> remoteForwardings = new HashMap<Integer, RemoteForwardingData>();
+
+    private final List<IChannelWorkerThread> listenerThreads = new ArrayList<IChannelWorkerThread>();
+
+    private boolean listenerThreadsAllowed = true;
+
+    /**
+     * Constructor for client-mode.
+     *
+     * @param tm
+     */
+    public ChannelManager(TransportManager tm) {
+        this.server_state = null;
+        this.tm = tm;
+        tm.registerMessageHandler(this, 80, 100);
+    }
+
+    /**
+     * Constructor for server-mode.
+     *
+     * @param state
+     */
+    public ChannelManager(ServerConnectionState state) {
+        this.server_state = state;
+        this.tm = state.tm;
+        tm.registerMessageHandler(this, 80, 100);
+    }
+
+    private Channel getChannel(int id) {
+        synchronized(channels) {
+            for(Channel c : channels) {
+                if(c.localID == id) {
+                    return c;
+                }
+            }
+        }
+        return null;
+    }
+
+    private void removeChannel(int id) {
+        synchronized(channels) {
+            for(Channel c : channels) {
+                if(c.localID == id) {
+                    channels.remove(c);
+                    break;
+                }
+            }
+        }
+    }
+
+    private int addChannel(Channel c) {
+        synchronized(channels) {
+            channels.add(c);
+            return nextLocalChannel++;
+        }
+    }
+
+    private void waitUntilChannelOpen(Channel c) throws IOException {
+        synchronized(c) {
+            while(c.state == Channel.STATE_OPENING) {
+                try {
+                    c.wait();
+                }
+                catch(InterruptedException e) {
+                    throw new InterruptedIOException(e.getMessage());
+                }
+            }
+
+            if(c.state != Channel.STATE_OPEN) {
+                removeChannel(c.localID);
+                throw c.getReasonClosed();
+            }
+        }
+    }
+
+    private void waitForGlobalSuccessOrFailure() throws IOException {
+        synchronized(channels) {
+            while((globalSuccessCounter == 0) && (globalFailedCounter == 0)) {
+                if(shutdown) {
+                    throw new IOException("The connection is being shutdown");
+                }
+
+                try {
+                    channels.wait();
+                }
+                catch(InterruptedException e) {
+                    throw new InterruptedIOException(e.getMessage());
+                }
+            }
+            if((globalFailedCounter == 0) && (globalSuccessCounter == 1)) {
+                return;
+            }
+            if((globalFailedCounter == 1) && (globalSuccessCounter == 0)) {
+                throw new IOException("The server denied the request (did you enable port forwarding?)");
+            }
+            throw new IOException("Illegal state. The server sent " + globalSuccessCounter
+                    + " SSH_MSG_REQUEST_SUCCESS and " + globalFailedCounter + " SSH_MSG_REQUEST_FAILURE messages.");
+        }
+    }
+
+    private void waitForChannelSuccessOrFailure(Channel c) throws IOException {
+        synchronized(c) {
+            while((c.successCounter == 0) && (c.failedCounter == 0)) {
+                if(c.state != Channel.STATE_OPEN) {
+                    throw c.getReasonClosed();
+                }
+                try {
+                    c.wait();
+                }
+                catch(InterruptedException ignore) {
+                    throw new InterruptedIOException();
+                }
+            }
+            if((c.failedCounter == 0) && (c.successCounter == 1)) {
+                return;
+            }
+            if((c.failedCounter == 1) && (c.successCounter == 0)) {
+                throw new IOException("The server denied the request.");
+            }
+            throw new IOException("Illegal state. The server sent " + c.successCounter
+                    + " SSH_MSG_CHANNEL_SUCCESS and " + c.failedCounter + " SSH_MSG_CHANNEL_FAILURE messages.");
+        }
+    }
+
+    public void registerX11Cookie(String hexFakeCookie, X11ServerData data) {
+        synchronized(x11_magic_cookies) {
+            x11_magic_cookies.put(hexFakeCookie, data);
+        }
+    }
+
+    public void unRegisterX11Cookie(String hexFakeCookie, boolean killChannels) {
+        if(hexFakeCookie == null) {
+            throw new IllegalStateException("hexFakeCookie may not be null");
+        }
+
+        synchronized(x11_magic_cookies) {
+            x11_magic_cookies.remove(hexFakeCookie);
+        }
+
+        if(killChannels == false) {
+            return;
+        }
+
+        log.debug("Closing all X11 channels for the given fake cookie");
+
+        List<Channel> channel_copy = new ArrayList<Channel>();
+
+        synchronized(channels) {
+            channel_copy.addAll(channels);
+        }
+
+        for(Channel c : channel_copy) {
+            synchronized(c) {
+                if(hexFakeCookie.equals(c.hexX11FakeCookie) == false) {
+                    continue;
+                }
+            }
+
+            try {
+                closeChannel(c, "Closing X11 channel since the corresponding session is closing", true);
+            }
+            catch(IOException ignored) {
+            }
+        }
+    }
+
+    public X11ServerData checkX11Cookie(String hexFakeCookie) {
+        synchronized(x11_magic_cookies) {
+            if(hexFakeCookie != null) {
+                return x11_magic_cookies.get(hexFakeCookie);
+            }
+        }
+        return null;
+    }
+
+    public void closeAllChannels() {
+        log.debug("Closing all channels");
+
+        List<Channel> channel_copy = new ArrayList<Channel>();
+
+        synchronized(channels) {
+            channel_copy.addAll(channels);
+        }
+
+        for(Channel c : channel_copy) {
+            try {
+                closeChannel(c, "Closing all channels", true);
+            }
+            catch(IOException ignored) {
+            }
+        }
+    }
+
+    public void closeChannel(Channel c, String reason, boolean force) throws IOException {
+        this.closeChannel(c, new ChannelClosedException(reason), force);
+    }
+
+    public void closeChannel(Channel c, IOException reason, boolean force) throws IOException {
+        byte msg[] = new byte[5];
+
+        synchronized(c) {
+            if(force) {
+                c.state = Channel.STATE_CLOSED;
+                c.EOF = true;
+            }
+
+            c.setReasonClosed(reason);
+
+            msg[0] = Packets.SSH_MSG_CHANNEL_CLOSE;
+            msg[1] = (byte) (c.remoteID >> 24);
+            msg[2] = (byte) (c.remoteID >> 16);
+            msg[3] = (byte) (c.remoteID >> 8);
+            msg[4] = (byte) (c.remoteID);
+
+            c.notifyAll();
+        }
+
+        synchronized(c.channelSendLock) {
+            if(c.closeMessageSent) {
+                return;
+            }
+            tm.sendMessage(msg);
+            c.closeMessageSent = true;
+        }
+
+        log.debug("Sent SSH_MSG_CHANNEL_CLOSE (channel " + c.localID + ")");
+    }
+
+    public void sendEOF(Channel c) throws IOException {
+        byte[] msg = new byte[5];
+
+        synchronized(c) {
+            if(c.state != Channel.STATE_OPEN) {
+                return;
+            }
+
+            msg[0] = Packets.SSH_MSG_CHANNEL_EOF;
+            msg[1] = (byte) (c.remoteID >> 24);
+            msg[2] = (byte) (c.remoteID >> 16);
+            msg[3] = (byte) (c.remoteID >> 8);
+            msg[4] = (byte) (c.remoteID);
+        }
+
+        synchronized(c.channelSendLock) {
+            if(c.closeMessageSent == true) {
+                return;
+            }
+            tm.sendMessage(msg);
+        }
+
+
+        log.debug("Sent EOF (Channel " + c.localID + "/" + c.remoteID + ")");
+    }
+
+    public void sendOpenConfirmation(Channel c) throws IOException {
+        PacketChannelOpenConfirmation pcoc = null;
+
+        synchronized(c) {
+            if(c.state != Channel.STATE_OPENING) {
+                return;
+            }
+
+            c.state = Channel.STATE_OPEN;
+
+            pcoc = new PacketChannelOpenConfirmation(c.remoteID, c.localID, c.localWindow, c.localMaxPacketSize);
+        }
+
+        synchronized(c.channelSendLock) {
+            if(c.closeMessageSent == true) {
+                return;
+            }
+            tm.sendMessage(pcoc.getPayload());
+        }
+    }
+
+    public void sendData(Channel c, byte[] buffer, int pos, int len) throws IOException {
+        while(len > 0) {
+            int thislen = 0;
+            byte[] msg;
+
+            synchronized(c) {
+                while(true) {
+                    if(c.state == Channel.STATE_CLOSED) {
+                        throw c.getReasonClosed();
+                    }
+                    if(c.state != Channel.STATE_OPEN) {
+                        throw new ChannelClosedException("SSH channel in strange state. (" + c.state + ")");
+                    }
+
+                    if(c.remoteWindow != 0) {
+                        break;
+                    }
+
+                    try {
+                        c.wait();
+                    }
+                    catch(InterruptedException e) {
+                        throw new InterruptedIOException(e.getMessage());
+                    }
+                }
+
+                /* len > 0, no sign extension can happen when comparing */
+
+                thislen = (c.remoteWindow >= len) ? len : (int) c.remoteWindow;
+
+                int estimatedMaxDataLen = c.remoteMaxPacketSize - (tm.getPacketOverheadEstimate() + 9);
+
+                /* The worst case scenario =) a true bottleneck */
+
+                if(estimatedMaxDataLen <= 0) {
+                    estimatedMaxDataLen = 1;
+                }
+
+                if(thislen > estimatedMaxDataLen) {
+                    thislen = estimatedMaxDataLen;
+                }
+
+                c.remoteWindow -= thislen;
+
+                msg = new byte[1 + 8 + thislen];
+
+                msg[0] = Packets.SSH_MSG_CHANNEL_DATA;
+                msg[1] = (byte) (c.remoteID >> 24);
+                msg[2] = (byte) (c.remoteID >> 16);
+                msg[3] = (byte) (c.remoteID >> 8);
+                msg[4] = (byte) (c.remoteID);
+                msg[5] = (byte) (thislen >> 24);
+                msg[6] = (byte) (thislen >> 16);
+                msg[7] = (byte) (thislen >> 8);
+                msg[8] = (byte) (thislen);
+
+                System.arraycopy(buffer, pos, msg, 9, thislen);
+            }
+
+            synchronized(c.channelSendLock) {
+                if(c.closeMessageSent) {
+                    throw c.getReasonClosed();
+                }
+                tm.sendMessage(msg);
+            }
+
+            pos += thislen;
+            len -= thislen;
+        }
+    }
+
+    public int requestGlobalForward(String bindAddress, int bindPort, String targetAddress, int targetPort)
+            throws IOException {
+        RemoteForwardingData rfd = new RemoteForwardingData();
+
+        rfd.bindAddress = bindAddress;
+        rfd.bindPort = bindPort;
+        rfd.targetAddress = targetAddress;
+        rfd.targetPort = targetPort;
+
+        synchronized(remoteForwardings) {
+            if(remoteForwardings.get(bindPort) != null) {
+                throw new IOException("There is already a forwarding for remote port " + bindPort);
+            }
+            remoteForwardings.put(bindPort, rfd);
+        }
+
+        synchronized(channels) {
+            globalSuccessCounter = globalFailedCounter = 0;
+        }
+
+        PacketGlobalForwardRequest pgf = new PacketGlobalForwardRequest(true, bindAddress, bindPort);
+        tm.sendMessage(pgf.getPayload());
+
+        log.debug("Requesting a remote forwarding ('" + bindAddress + "', " + bindPort + ")");
+
+        try {
+            waitForGlobalSuccessOrFailure();
+        }
+        catch(IOException e) {
+            synchronized(remoteForwardings) {
+                remoteForwardings.remove(bindPort);
+            }
+            throw e;
+        }
+
+        return bindPort;
+    }
+
+    public void requestCancelGlobalForward(int bindPort) throws IOException {
+        RemoteForwardingData rfd;
+
+        synchronized(remoteForwardings) {
+            rfd = remoteForwardings.get(bindPort);
+
+            if(rfd == null) {
+                throw new IOException("Sorry, there is no known remote forwarding for remote port " + bindPort);
+            }
+        }
+
+        synchronized(channels) {
+            globalSuccessCounter = globalFailedCounter = 0;
+        }
+
+        PacketGlobalCancelForwardRequest pgcf = new PacketGlobalCancelForwardRequest(true, rfd.bindAddress,
+                rfd.bindPort);
+        tm.sendMessage(pgcf.getPayload());
+
+        log.debug("Requesting cancelation of remote forward ('" + rfd.bindAddress + "', " + rfd.bindPort + ")");
+
+        waitForGlobalSuccessOrFailure();
+
+		/* Only now we are sure that no more forwarded connections will arrive */
+
+        synchronized(remoteForwardings) {
+            remoteForwardings.remove(bindPort);
+        }
+    }
+
+    public void registerThread(IChannelWorkerThread thr) throws IOException {
+        synchronized(listenerThreads) {
+            if(listenerThreadsAllowed == false) {
+                throw new IOException("Too late, this connection is closed.");
+            }
+            listenerThreads.add(thr);
+        }
+    }
+
+    public Channel openDirectTCPIPChannel(String host_to_connect, int port_to_connect, String originator_IP_address,
+                                          int originator_port) throws IOException {
+        Channel c = new Channel(this);
+
+        synchronized(c) {
+            c.localID = addChannel(c);
+            // end of synchronized block forces writing out to main memory
+        }
+
+        PacketOpenDirectTCPIPChannel dtc = new PacketOpenDirectTCPIPChannel(c.localID, c.localWindow,
+                c.localMaxPacketSize, host_to_connect, port_to_connect, originator_IP_address, originator_port);
+
+        tm.sendMessage(dtc.getPayload());
+
+        waitUntilChannelOpen(c);
+
+        return c;
+    }
+
+    public Channel openSessionChannel() throws IOException {
+        Channel c = new Channel(this);
+
+        synchronized(c) {
+            c.localID = addChannel(c);
+            // end of synchronized block forces the writing out to main memory
+        }
+
+        log.debug("Sending SSH_MSG_CHANNEL_OPEN (Channel " + c.localID + ")");
+
+        PacketOpenSessionChannel smo = new PacketOpenSessionChannel(c.localID, c.localWindow, c.localMaxPacketSize);
+        tm.sendMessage(smo.getPayload());
+
+        waitUntilChannelOpen(c);
+
+        return c;
+    }
+
+    public void requestPTY(Channel c, String term, int term_width_characters, int term_height_characters,
+                           int term_width_pixels, int term_height_pixels, byte[] terminal_modes) throws IOException {
+        PacketSessionPtyRequest spr;
+
+        synchronized(c) {
+            if(c.state != Channel.STATE_OPEN) {
+                throw c.getReasonClosed();
+            }
+            spr = new PacketSessionPtyRequest(c.remoteID, true, term, term_width_characters, term_height_characters,
+                    term_width_pixels, term_height_pixels, terminal_modes);
+
+            c.successCounter = c.failedCounter = 0;
+        }
+
+        synchronized(c.channelSendLock) {
+            if(c.closeMessageSent) {
+                throw c.getReasonClosed();
+            }
+            tm.sendMessage(spr.getPayload());
+        }
+
+        try {
+            waitForChannelSuccessOrFailure(c);
+        }
+        catch(IOException e) {
+            throw new IOException("PTY request failed", e);
+        }
+    }
+
+    public void requestWindowChange(Channel c, int term_width_characters, int term_height_characters,
+                                    int term_width_pixels, int term_height_pixels) throws IOException {
+        PacketWindowChange pwc;
+
+        synchronized(c) {
+            if(c.state != Channel.STATE_OPEN) {
+                throw c.getReasonClosed();
+            }
+            pwc = new PacketWindowChange(c.remoteID, term_width_characters, term_height_characters,
+                    term_width_pixels, term_height_pixels);
+
+            c.successCounter = c.failedCounter = 0;
+        }
+
+        synchronized(c.channelSendLock) {
+            if(c.closeMessageSent) {
+                throw c.getReasonClosed();
+            }
+            tm.sendMessage(pwc.getPayload());
+        }
+
+        try {
+            waitForChannelSuccessOrFailure(c);
+        }
+        catch(IOException e) {
+            throw new IOException("The window-change request failed.", e);
+        }
+    }
+
+    public void requestX11(Channel c, boolean singleConnection, String x11AuthenticationProtocol,
+                           String x11AuthenticationCookie, int x11ScreenNumber) throws IOException {
+        PacketSessionX11Request psr;
+
+        synchronized(c) {
+            if(c.state != Channel.STATE_OPEN) {
+                throw c.getReasonClosed();
+            }
+            psr = new PacketSessionX11Request(c.remoteID, true, singleConnection, x11AuthenticationProtocol,
+                    x11AuthenticationCookie, x11ScreenNumber);
+
+            c.successCounter = c.failedCounter = 0;
+        }
+
+        synchronized(c.channelSendLock) {
+            if(c.closeMessageSent) {
+                throw c.getReasonClosed();
+            }
+            tm.sendMessage(psr.getPayload());
+        }
+
+        log.debug("Requesting X11 forwarding (Channel " + c.localID + "/" + c.remoteID + ")");
+
+        try {
+            waitForChannelSuccessOrFailure(c);
+        }
+        catch(IOException e) {
+            throw new IOException("The X11 request failed.", e);
+        }
+    }
+
+    public void requestSubSystem(Channel c, String subSystemName) throws IOException {
+        PacketSessionSubsystemRequest ssr;
+
+        synchronized(c) {
+            if(c.state != Channel.STATE_OPEN) {
+                throw c.getReasonClosed();
+            }
+            ssr = new PacketSessionSubsystemRequest(c.remoteID, true, subSystemName);
+
+            c.successCounter = c.failedCounter = 0;
+        }
+
+        synchronized(c.channelSendLock) {
+            if(c.closeMessageSent) {
+                throw c.getReasonClosed();
+            }
+            tm.sendMessage(ssr.getPayload());
+        }
+
+        try {
+            waitForChannelSuccessOrFailure(c);
+        }
+        catch(IOException e) {
+            throw new IOException("The subsystem request failed.", e);
+        }
+    }
+
+    public void requestExecCommand(Channel c, String cmd) throws IOException {
+        this.requestExecCommand(c, cmd, null);
+    }
+
+    /**
+     * @param charsetName The charset used to convert between Java Unicode Strings and byte encodings
+     */
+    public void requestExecCommand(Channel c, String cmd, String charsetName) throws IOException {
+        PacketSessionExecCommand sm;
+
+        synchronized(c) {
+            if(c.state != Channel.STATE_OPEN) {
+                throw c.getReasonClosed();
+            }
+            sm = new PacketSessionExecCommand(c.remoteID, true, cmd, charsetName);
+
+            c.successCounter = c.failedCounter = 0;
+        }
+
+        synchronized(c.channelSendLock) {
+            if(c.closeMessageSent) {
+                throw c.getReasonClosed();
+            }
+            tm.sendMessage(sm.getPayload());
+        }
+
+        log.debug("Executing command (channel " + c.localID + ", '" + cmd + "')");
+
+        try {
+            waitForChannelSuccessOrFailure(c);
+        }
+        catch(IOException e) {
+            throw new IOException("The execute request failed.", e);
+        }
+    }
+
+    public void requestShell(Channel c) throws IOException {
+        PacketSessionStartShell sm;
+
+        synchronized(c) {
+            if(c.state != Channel.STATE_OPEN) {
+                throw c.getReasonClosed();
+            }
+            sm = new PacketSessionStartShell(c.remoteID, true);
+
+            c.successCounter = c.failedCounter = 0;
+        }
+
+        synchronized(c.channelSendLock) {
+            if(c.closeMessageSent) {
+                throw c.getReasonClosed();
+            }
+            tm.sendMessage(sm.getPayload());
+        }
+
+        try {
+            waitForChannelSuccessOrFailure(c);
+        }
+        catch(IOException e) {
+            throw new IOException("The shell request failed.", e);
+        }
+    }
+
+    public void msgChannelExtendedData(byte[] msg) throws IOException {
+        if(msg.length <= 13) {
+            throw new PacketFormatException(String.format("SSH_MSG_CHANNEL_EXTENDED_DATA message has wrong size (%d)", msg.length));
+        }
+
+        int id = ((msg[1] & 0xff) << 24) | ((msg[2] & 0xff) << 16) | ((msg[3] & 0xff) << 8) | (msg[4] & 0xff);
+        int dataType = ((msg[5] & 0xff) << 24) | ((msg[6] & 0xff) << 16) | ((msg[7] & 0xff) << 8) | (msg[8] & 0xff);
+        int len = ((msg[9] & 0xff) << 24) | ((msg[10] & 0xff) << 16) | ((msg[11] & 0xff) << 8) | (msg[12] & 0xff);
+
+        Channel c = getChannel(id);
+
+        if(c == null) {
+            throw new PacketTypeException("Unexpected SSH_MSG_CHANNEL_EXTENDED_DATA message for non-existent channel " + id);
+        }
+
+        if(dataType != Packets.SSH_EXTENDED_DATA_STDERR) {
+            throw new PacketFormatException("SSH_MSG_CHANNEL_EXTENDED_DATA message has unknown type (" + dataType + ")");
+        }
+
+        if(len != (msg.length - 13)) {
+            throw new PacketFormatException("SSH_MSG_CHANNEL_EXTENDED_DATA message has wrong len (calculated " + (msg.length - 13)
+                    + ", got " + len + ")");
+        }
+
+        log.debug("Got SSH_MSG_CHANNEL_EXTENDED_DATA (channel " + id + ", " + len + ")");
+
+        synchronized(c) {
+            if(c.state == Channel.STATE_CLOSED) {
+                return; // ignore
+            }
+
+            if(c.state != Channel.STATE_OPEN) {
+                throw new PacketTypeException("Got SSH_MSG_CHANNEL_EXTENDED_DATA, but channel is not in correct state ("
+                        + c.state + ")");
+            }
+
+            if(c.localWindow < len) {
+                throw new PacketFormatException("Remote sent too much data, does not fit into window.");
+            }
+
+            c.localWindow -= len;
+
+            System.arraycopy(msg, 13, c.stderrBuffer, c.stderrWritepos, len);
+            c.stderrWritepos += len;
+
+            c.notifyAll();
+        }
+    }
+
+    /**
+     * Wait until for a condition.
+     *
+     * @param c              Channel
+     * @param timeout        in ms, 0 means no timeout.
+     * @param condition_mask minimum event mask (at least one of the conditions must be fulfilled)
+     * @return all current events
+     */
+    public int waitForCondition(Channel c, long timeout, int condition_mask) throws IOException {
+        long end_time = 0;
+        boolean end_time_set = false;
+
+        synchronized(c) {
+            while(true) {
+                int current_cond = 0;
+
+                int stdoutAvail = c.stdoutWritepos - c.stdoutReadpos;
+                int stderrAvail = c.stderrWritepos - c.stderrReadpos;
+
+                if(stdoutAvail > 0) {
+                    current_cond = current_cond | ChannelCondition.STDOUT_DATA;
+                }
+
+                if(stderrAvail > 0) {
+                    current_cond = current_cond | ChannelCondition.STDERR_DATA;
+                }
+
+                if(c.EOF) {
+                    current_cond = current_cond | ChannelCondition.EOF;
+                }
+
+                if(c.getExitStatus() != null) {
+                    current_cond = current_cond | ChannelCondition.EXIT_STATUS;
+                }
+
+                if(c.getExitSignal() != null) {
+                    current_cond = current_cond | ChannelCondition.EXIT_SIGNAL;
+                }
+
+                if(c.state == Channel.STATE_CLOSED) {
+                    return current_cond | ChannelCondition.CLOSED | ChannelCondition.EOF;
+                }
+
+                if((current_cond & condition_mask) != 0) {
+                    return current_cond;
+                }
+
+                if(timeout > 0) {
+                    if(!end_time_set) {
+                        end_time = System.currentTimeMillis() + timeout;
+                        end_time_set = true;
+                    }
+                    else {
+                        timeout = end_time - System.currentTimeMillis();
+
+                        if(timeout <= 0) {
+                            return current_cond | ChannelCondition.TIMEOUT;
+                        }
+                    }
+                }
+
+                try {
+                    if(timeout > 0) {
+                        c.wait(timeout);
+                    }
+                    else {
+                        c.wait();
+                    }
+                }
+                catch(InterruptedException e) {
+                    throw new InterruptedIOException(e.getMessage());
+                }
+            }
+        }
+    }
+
+    public int getAvailable(Channel c, boolean extended) throws IOException {
+        synchronized(c) {
+            int avail;
+
+            if(extended) {
+                avail = c.stderrWritepos - c.stderrReadpos;
+            }
+            else {
+                avail = c.stdoutWritepos - c.stdoutReadpos;
+            }
+
+            return ((avail > 0) ? avail : (c.EOF ? -1 : 0));
+        }
+    }
+
+    public int getChannelData(Channel c, boolean extended, byte[] target, int off, int len) throws IOException {
+        int copylen = 0;
+        int increment = 0;
+        int remoteID = 0;
+        int localID = 0;
+
+        synchronized(c) {
+            int stdoutAvail = 0;
+            int stderrAvail = 0;
+
+            while(true) {
+                /*
+                 * Data available? We have to return remaining data even if the
+                 * channel is already closed.
+                 */
+
+                stdoutAvail = c.stdoutWritepos - c.stdoutReadpos;
+                stderrAvail = c.stderrWritepos - c.stderrReadpos;
+
+                if((!extended) && (stdoutAvail != 0)) {
+                    break;
+                }
+
+                if((extended) && (stderrAvail != 0)) {
+                    break;
+                }
+
+                /* Do not wait if more data will never arrive (EOF or CLOSED) */
+
+                if((c.EOF) || (c.state != Channel.STATE_OPEN)) {
+                    return -1;
+                }
+
+                try {
+                    c.wait();
+                }
+                catch(InterruptedException e) {
+                    throw new InterruptedIOException(e.getMessage());
+                }
+            }
+
+            /* OK, there is some data. Return it. */
+
+            if(!extended) {
+                copylen = (stdoutAvail > len) ? len : stdoutAvail;
+                System.arraycopy(c.stdoutBuffer, c.stdoutReadpos, target, off, copylen);
+                c.stdoutReadpos += copylen;
+
+                if(c.stdoutReadpos != c.stdoutWritepos)
+
+                {
+                    System.arraycopy(c.stdoutBuffer, c.stdoutReadpos, c.stdoutBuffer, 0, c.stdoutWritepos
+                            - c.stdoutReadpos);
+                }
+
+                c.stdoutWritepos -= c.stdoutReadpos;
+                c.stdoutReadpos = 0;
+            }
+            else {
+                copylen = (stderrAvail > len) ? len : stderrAvail;
+                System.arraycopy(c.stderrBuffer, c.stderrReadpos, target, off, copylen);
+                c.stderrReadpos += copylen;
+
+                if(c.stderrReadpos != c.stderrWritepos)
+
+                {
+                    System.arraycopy(c.stderrBuffer, c.stderrReadpos, c.stderrBuffer, 0, c.stderrWritepos
+                            - c.stderrReadpos);
+                }
+
+                c.stderrWritepos -= c.stderrReadpos;
+                c.stderrReadpos = 0;
+            }
+
+            if(c.state != Channel.STATE_OPEN) {
+                return copylen;
+            }
+
+            if(c.localWindow < ((Channel.CHANNEL_BUFFER_SIZE + 1) / 2)) {
+                int minFreeSpace = Math.min(Channel.CHANNEL_BUFFER_SIZE - c.stdoutWritepos,
+                        Channel.CHANNEL_BUFFER_SIZE - c.stderrWritepos);
+
+                increment = minFreeSpace - c.localWindow;
+                c.localWindow = minFreeSpace;
+            }
+
+            remoteID = c.remoteID; /* read while holding the lock */
+            localID = c.localID; /* read while holding the lock */
+        }
+
+        /*
+         * If a consumer reads stdout and stdin in parallel, we may end up with
+         * sending two msgWindowAdjust messages. Luckily, it
+         * does not matter in which order they arrive at the server.
+         */
+
+        if(increment > 0) {
+            log.debug("Sending SSH_MSG_CHANNEL_WINDOW_ADJUST (channel " + localID + ", " + increment + ")");
+
+            synchronized(c.channelSendLock) {
+                byte[] msg = c.msgWindowAdjust;
+
+                msg[0] = Packets.SSH_MSG_CHANNEL_WINDOW_ADJUST;
+                msg[1] = (byte) (remoteID >> 24);
+                msg[2] = (byte) (remoteID >> 16);
+                msg[3] = (byte) (remoteID >> 8);
+                msg[4] = (byte) (remoteID);
+                msg[5] = (byte) (increment >> 24);
+                msg[6] = (byte) (increment >> 16);
+                msg[7] = (byte) (increment >> 8);
+                msg[8] = (byte) (increment);
+
+                if(!c.closeMessageSent) {
+                    tm.sendMessage(msg);
+                }
+            }
+        }
+
+        return copylen;
+    }
+
+    public void msgChannelData(byte[] msg) throws IOException {
+        if(msg.length <= 9) {
+            throw new PacketFormatException(String.format("SSH_MSG_CHANNEL_DATA message has wrong size (%d)", msg.length));
+        }
+
+        int id = ((msg[1] & 0xff) << 24) | ((msg[2] & 0xff) << 16) | ((msg[3] & 0xff) << 8) | (msg[4] & 0xff);
+        int len = ((msg[5] & 0xff) << 24) | ((msg[6] & 0xff) << 16) | ((msg[7] & 0xff) << 8) | (msg[8] & 0xff);
+
+        Channel c = getChannel(id);
+
+        if(c == null) {
+            throw new PacketTypeException("Unexpected SSH_MSG_CHANNEL_DATA message for non-existent channel " + id);
+        }
+
+        if(len != (msg.length - 9)) {
+            throw new PacketFormatException("SSH_MSG_CHANNEL_DATA message has wrong len (calculated " + (msg.length - 9) + ", got "
+                    + len + ")");
+        }
+
+        log.debug("Got SSH_MSG_CHANNEL_DATA (channel " + id + ", " + len + ")");
+
+        synchronized(c) {
+            if(c.state == Channel.STATE_CLOSED) {
+                return; // ignore
+            }
+
+            if(c.state != Channel.STATE_OPEN) {
+                throw new PacketTypeException("Got SSH_MSG_CHANNEL_DATA, but channel is not in correct state (" + c.state + ")");
+            }
+
+            if(c.localWindow < len) {
+                throw new IOException("Remote sent too much data, does not fit into window.");
+            }
+
+            c.localWindow -= len;
+
+            System.arraycopy(msg, 9, c.stdoutBuffer, c.stdoutWritepos, len);
+            c.stdoutWritepos += len;
+
+            c.notifyAll();
+        }
+    }
+
+    public void msgChannelWindowAdjust(byte[] msg) throws IOException {
+        if(msg.length != 9) {
+            throw new PacketFormatException(String.format("SSH_MSG_CHANNEL_WINDOW_ADJUST message has wrong size (%d)", msg.length));
+        }
+
+        int id = ((msg[1] & 0xff) << 24) | ((msg[2] & 0xff) << 16) | ((msg[3] & 0xff) << 8) | (msg[4] & 0xff);
+        int windowChange = ((msg[5] & 0xff) << 24) | ((msg[6] & 0xff) << 16) | ((msg[7] & 0xff) << 8) | (msg[8] & 0xff);
+
+        Channel c = getChannel(id);
+
+        if(c == null) {
+            throw new PacketTypeException("Unexpected SSH_MSG_CHANNEL_WINDOW_ADJUST message for non-existent channel " + id);
+        }
+
+        synchronized(c) {
+            final long huge = 0xFFFFffffL; /* 2^32 - 1 */
+
+            c.remoteWindow += (windowChange & huge); /* avoid sign extension */
+
+			/* TODO - is this a good heuristic? */
+
+            if((c.remoteWindow > huge)) {
+                c.remoteWindow = huge;
+            }
+
+            c.notifyAll();
+        }
+
+
+        log.debug("Got SSH_MSG_CHANNEL_WINDOW_ADJUST (channel " + id + ", " + windowChange + ")");
+    }
+
+    public void msgChannelOpen(byte[] msg) throws IOException {
+        TypesReader tr = new TypesReader(msg);
+
+        tr.readByte(); // skip packet type
+        String channelType = tr.readString();
+        int remoteID = tr.readUINT32(); /* sender channel */
+        int remoteWindow = tr.readUINT32(); /* initial window size */
+        int remoteMaxPacketSize = tr.readUINT32(); /* maximum packet size */
+
+        if("x11".equals(channelType)) {
+            synchronized(x11_magic_cookies) {
+                /* If we did not request X11 forwarding, then simply ignore this bogus request. */
+
+                if(x11_magic_cookies.size() == 0) {
+                    PacketChannelOpenFailure pcof = new PacketChannelOpenFailure(remoteID,
+                            Packets.SSH_OPEN_ADMINISTRATIVELY_PROHIBITED, "X11 forwarding not activated", "");
+
+                    tm.sendAsynchronousMessage(pcof.getPayload());
+
+                    log.warning("Unexpected X11 request, denying it!");
+
+                    return;
+                }
+            }
+
+            String remoteOriginatorAddress = tr.readString();
+            int remoteOriginatorPort = tr.readUINT32();
+
+            Channel c = new Channel(this);
+
+            synchronized(c) {
+                c.remoteID = remoteID;
+                c.remoteWindow = remoteWindow & 0xFFFFffffL; /* properly convert UINT32 to long */
+                c.remoteMaxPacketSize = remoteMaxPacketSize;
+                c.localID = addChannel(c);
+            }
+
+			/*
+             * The open confirmation message will be sent from another thread
+			 */
+
+            RemoteX11AcceptThread rxat = new RemoteX11AcceptThread(c, remoteOriginatorAddress, remoteOriginatorPort);
+            rxat.setDaemon(true);
+            rxat.start();
+
+            return;
+        }
+
+        if("forwarded-tcpip".equals(channelType)) {
+            String remoteConnectedAddress = tr.readString(); /* address that was connected */
+            int remoteConnectedPort = tr.readUINT32(); /* port that was connected */
+            String remoteOriginatorAddress = tr.readString(); /* originator IP address */
+            int remoteOriginatorPort = tr.readUINT32(); /* originator port */
+
+            RemoteForwardingData rfd;
+
+            synchronized(remoteForwardings) {
+                rfd = remoteForwardings.get(remoteConnectedPort);
+            }
+
+            if(rfd == null) {
+                PacketChannelOpenFailure pcof = new PacketChannelOpenFailure(remoteID,
+                        Packets.SSH_OPEN_ADMINISTRATIVELY_PROHIBITED,
+                        "No thanks, unknown port in forwarded-tcpip request", "");
+
+				/* Always try to be polite. */
+
+                tm.sendAsynchronousMessage(pcof.getPayload());
+
+                log.debug("Unexpected forwarded-tcpip request, denying it!");
+
+                return;
+            }
+
+            Channel c = new Channel(this);
+
+            synchronized(c) {
+                c.remoteID = remoteID;
+                c.remoteWindow = remoteWindow & 0xFFFFffffL; /* convert UINT32 to long */
+                c.remoteMaxPacketSize = remoteMaxPacketSize;
+                c.localID = addChannel(c);
+            }
+
+			/*
+			 * The open confirmation message will be sent from another thread.
+			 */
+
+            RemoteAcceptThread rat = new RemoteAcceptThread(c, remoteConnectedAddress, remoteConnectedPort,
+                    remoteOriginatorAddress, remoteOriginatorPort, rfd.targetAddress, rfd.targetPort);
+
+            rat.setDaemon(true);
+            rat.start();
+
+            return;
+        }
+
+        if((server_state != null) && ("session".equals(channelType))) {
+            ServerConnectionCallback cb;
+
+            synchronized(server_state) {
+                cb = server_state.cb_conn;
+            }
+
+            if(cb == null) {
+                tm.sendAsynchronousMessage(new PacketChannelOpenFailure(remoteID, Packets.SSH_OPEN_ADMINISTRATIVELY_PROHIBITED,
+                        "Sessions are currently not enabled", "en").getPayload());
+
+                return;
+            }
+
+            final Channel c = new Channel(this);
+
+            synchronized(c) {
+                c.remoteID = remoteID;
+                c.remoteWindow = remoteWindow & 0xFFFFffffL; /* convert UINT32 to long */
+                c.remoteMaxPacketSize = remoteMaxPacketSize;
+                c.localID = addChannel(c);
+                c.state = Channel.STATE_OPEN;
+                c.ss = new ServerSessionImpl(c);
+            }
+
+            PacketChannelOpenConfirmation pcoc = new PacketChannelOpenConfirmation(c.remoteID, c.localID,
+                    c.localWindow, c.localMaxPacketSize);
+
+            tm.sendAsynchronousMessage(pcoc.getPayload());
+
+            c.ss.sscb = cb.acceptSession(c.ss);
+
+            return;
+        }
+
+		/* Tell the server that we have no idea what it is talking about */
+
+        PacketChannelOpenFailure pcof = new PacketChannelOpenFailure(remoteID, Packets.SSH_OPEN_UNKNOWN_CHANNEL_TYPE,
+                "Unknown channel type", "");
+
+        tm.sendAsynchronousMessage(pcof.getPayload());
+
+
+        log.warning("The peer tried to open an unsupported channel type (" + channelType + ")");
+    }
+
+    /* Starts the given runnable in a foreground (non-daemon) thread */
+    private void runAsync(Runnable r) {
+        Thread t = new Thread(r);
+        t.start();
+    }
+
+    public void msgChannelRequest(byte[] msg) throws IOException {
+        TypesReader tr = new TypesReader(msg);
+
+        tr.readByte(); // skip packet type
+        int id = tr.readUINT32();
+
+        Channel c = getChannel(id);
+
+        if(c == null) {
+            throw new IOException("Unexpected SSH_MSG_CHANNEL_REQUEST message for non-existent channel " + id);
+        }
+
+        ServerSessionImpl server_session = null;
+
+        if(server_state != null) {
+            synchronized(c) {
+                server_session = c.ss;
+            }
+        }
+
+        String type = tr.readString("US-ASCII");
+        boolean wantReply = tr.readBoolean();
+
+        log.debug("Got SSH_MSG_CHANNEL_REQUEST (channel " + id + ", '" + type + "')");
+
+        if(type.equals("exit-status")) {
+            if(wantReply) {
+                throw new IOException(
+                        "Badly formatted SSH_MSG_CHANNEL_REQUEST exit-status message, 'want reply' is true");
+            }
+
+            int exit_status = tr.readUINT32();
+
+            if(tr.remain() != 0) {
+                throw new IOException("Badly formatted SSH_MSG_CHANNEL_REQUEST message");
+            }
+
+            synchronized(c) {
+                c.exit_status = exit_status;
+                c.notifyAll();
+            }
+
+            log.debug("Got EXIT STATUS (channel " + id + ", status " + exit_status + ")");
+
+            return;
+        }
+
+        if((server_state == null) && (type.equals("exit-signal"))) {
+            if(wantReply) {
+                throw new IOException(
+                        "Badly formatted SSH_MSG_CHANNEL_REQUEST exit-signal message, 'want reply' is true");
+            }
+
+            String signame = tr.readString("US-ASCII");
+            tr.readBoolean();
+            tr.readString();
+            tr.readString();
+
+            if(tr.remain() != 0) {
+                throw new IOException("Badly formatted SSH_MSG_CHANNEL_REQUEST message");
+            }
+
+            synchronized(c) {
+                c.exit_signal = signame;
+                c.notifyAll();
+            }
+
+            log.debug("Got EXIT SIGNAL (channel " + id + ", signal " + signame + ")");
+
+            return;
+        }
+
+        if((server_session != null) && (type.equals("pty-req"))) {
+            PtySettings pty = new PtySettings();
+
+            pty.term = tr.readString();
+            pty.term_width_characters = tr.readUINT32();
+            pty.term_height_characters = tr.readUINT32();
+            pty.term_width_pixels = tr.readUINT32();
+            pty.term_height_pixels = tr.readUINT32();
+            pty.terminal_modes = tr.readByteString();
+
+            if(tr.remain() != 0) {
+                throw new IOException("Badly formatted SSH_MSG_CHANNEL_REQUEST message");
+            }
+
+            Runnable run_after_sending_success = null;
+
+            ServerSessionCallback sscb = server_session.getServerSessionCallback();
+
+            if(sscb != null) {
+                run_after_sending_success = sscb.requestPtyReq(server_session, pty);
+            }
+
+            if(wantReply) {
+                if(run_after_sending_success != null) {
+                    tm.sendAsynchronousMessage(new PacketChannelSuccess(c.remoteID).getPayload());
+                }
+                else {
+                    tm.sendAsynchronousMessage(new PacketChannelFailure(c.remoteID).getPayload());
+                }
+            }
+
+            if(run_after_sending_success != null) {
+                runAsync(run_after_sending_success);
+            }
+
+            return;
+        }
+
+        if((server_session != null) && (type.equals("shell"))) {
+            if(tr.remain() != 0) {
+                throw new IOException("Badly formatted SSH_MSG_CHANNEL_REQUEST message");
+            }
+
+            Runnable run_after_sending_success = null;
+            ServerSessionCallback sscb = server_session.getServerSessionCallback();
+
+            if(sscb != null) {
+                run_after_sending_success = sscb.requestShell(server_session);
+            }
+
+            if(wantReply) {
+                if(run_after_sending_success != null) {
+                    tm.sendAsynchronousMessage(new PacketChannelSuccess(c.remoteID).getPayload());
+                }
+                else {
+                    tm.sendAsynchronousMessage(new PacketChannelFailure(c.remoteID).getPayload());
+                }
+            }
+
+            if(run_after_sending_success != null) {
+                runAsync(run_after_sending_success);
+            }
+
+            return;
+        }
+
+        if((server_session != null) && (type.equals("exec"))) {
+            String command = tr.readString();
+
+            if(tr.remain() != 0) {
+                throw new IOException("Badly formatted SSH_MSG_CHANNEL_REQUEST message");
+            }
+
+            Runnable run_after_sending_success = null;
+            ServerSessionCallback sscb = server_session.getServerSessionCallback();
+
+            if(sscb != null) {
+                run_after_sending_success = sscb.requestExec(server_session, command);
+            }
+
+            if(wantReply) {
+                if(run_after_sending_success != null) {
+                    tm.sendAsynchronousMessage(new PacketChannelSuccess(c.remoteID).getPayload());
+                }
+                else {
+                    tm.sendAsynchronousMessage(new PacketChannelFailure(c.remoteID).getPayload());
+                }
+            }
+
+            if(run_after_sending_success != null) {
+                runAsync(run_after_sending_success);
+            }
+
+            return;
+        }
+
+		/* We simply ignore unknown channel requests, however, if the server wants a reply,
+		 * then we signal that we have no idea what it is about.
+		 */
+
+        if(wantReply) {
+            tm.sendAsynchronousMessage(new PacketChannelFailure(c.remoteID).getPayload());
+        }
+
+        log.debug("Channel request '" + type + "' is not known, ignoring it");
+    }
+
+    public void msgChannelEOF(byte[] msg) throws IOException {
+        if(msg.length != 5) {
+            throw new PacketFormatException(String.format("SSH_MSG_CHANNEL_EOF message has wrong size (%d)", msg.length));
+        }
+
+        int id = ((msg[1] & 0xff) << 24) | ((msg[2] & 0xff) << 16) | ((msg[3] & 0xff) << 8) | (msg[4] & 0xff);
+
+        Channel c = getChannel(id);
+
+        if(c == null) {
+            throw new PacketTypeException("Unexpected SSH_MSG_CHANNEL_EOF message for non-existent channel " + id);
+        }
+
+        synchronized(c) {
+            c.EOF = true;
+            c.notifyAll();
+        }
+
+        log.debug("Got SSH_MSG_CHANNEL_EOF (channel " + id + ")");
+    }
+
+    public void msgChannelClose(byte[] msg) throws IOException {
+        if(msg.length != 5) {
+            throw new PacketFormatException("SSH_MSG_CHANNEL_CLOSE message has wrong size (" + msg.length + ")");
+        }
+
+        int id = ((msg[1] & 0xff) << 24) | ((msg[2] & 0xff) << 16) | ((msg[3] & 0xff) << 8) | (msg[4] & 0xff);
+
+        Channel c = getChannel(id);
+
+        if(c == null) {
+            throw new IOException("Unexpected SSH_MSG_CHANNEL_CLOSE message for non-existent channel " + id);
+        }
+
+        synchronized(c) {
+            c.EOF = true;
+            c.state = Channel.STATE_CLOSED;
+            c.setReasonClosed(new ChannelClosedException("Close requested by remote"));
+            c.closeMessageRecv = true;
+
+            removeChannel(c.localID);
+
+            c.notifyAll();
+        }
+
+        log.debug("Got SSH_MSG_CHANNEL_CLOSE (channel " + id + ")");
+    }
+
+    public void msgChannelSuccess(byte[] msg) throws IOException {
+        if(msg.length != 5) {
+            throw new PacketFormatException("SSH_MSG_CHANNEL_SUCCESS message has wrong size (" + msg.length + ")");
+        }
+
+        int id = ((msg[1] & 0xff) << 24) | ((msg[2] & 0xff) << 16) | ((msg[3] & 0xff) << 8) | (msg[4] & 0xff);
+
+        Channel c = getChannel(id);
+
+        if(c == null) {
+            throw new PacketTypeException("Unexpected SSH_MSG_CHANNEL_SUCCESS message for non-existent channel " + id);
+        }
+
+        synchronized(c) {
+            c.successCounter++;
+            c.notifyAll();
+        }
+
+        log.debug("Got SSH_MSG_CHANNEL_SUCCESS (channel " + id + ")");
+    }
+
+    public void msgChannelFailure(byte[] msg) throws IOException {
+        if(msg.length != 5) {
+            throw new PacketFormatException(String.format("SSH_MSG_CHANNEL_FAILURE message has wrong size (%d)", msg.length));
+        }
+
+        int id = ((msg[1] & 0xff) << 24) | ((msg[2] & 0xff) << 16) | ((msg[3] & 0xff) << 8) | (msg[4] & 0xff);
+
+        Channel c = getChannel(id);
+
+        if(c == null) {
+            throw new PacketTypeException("Unexpected SSH_MSG_CHANNEL_FAILURE message for non-existent channel " + id);
+        }
+
+        synchronized(c) {
+            c.failedCounter++;
+            c.notifyAll();
+        }
+
+        log.debug("Got SSH_MSG_CHANNEL_FAILURE (channel " + id + ")");
+    }
+
+    public void msgChannelOpenConfirmation(byte[] msg) throws IOException {
+        PacketChannelOpenConfirmation sm = new PacketChannelOpenConfirmation(msg);
+
+        Channel c = getChannel(sm.getRecipientChannelID());
+
+        if(c == null) {
+            throw new PacketTypeException("Unexpected SSH_MSG_CHANNEL_OPEN_CONFIRMATION message for non-existent channel "
+                    + sm.getRecipientChannelID());
+        }
+
+        synchronized(c) {
+            if(c.state != Channel.STATE_OPENING) {
+                throw new PacketTypeException("Unexpected SSH_MSG_CHANNEL_OPEN_CONFIRMATION message for channel "
+                        + sm.getRecipientChannelID());
+            }
+
+            c.remoteID = sm.getSenderChannelID();
+            c.remoteWindow = sm.getInitialWindowSize() & 0xFFFFffffL; /* convert UINT32 to long */
+            c.remoteMaxPacketSize = sm.getMaxPacketSize();
+            c.state = Channel.STATE_OPEN;
+            c.notifyAll();
+        }
+
+        log.debug("Got SSH_MSG_CHANNEL_OPEN_CONFIRMATION (channel " + sm.getRecipientChannelID() + " / remote: "
+                + sm.getSenderChannelID() + ")");
+    }
+
+    public void msgChannelOpenFailure(byte[] msg) throws IOException {
+        if(msg.length < 5) {
+            throw new PacketFormatException(String.format("SSH_MSG_CHANNEL_OPEN_FAILURE message has wrong size (%d)", msg.length));
+        }
+
+        TypesReader tr = new TypesReader(msg);
+
+        tr.readByte(); // skip packet type
+        int id = tr.readUINT32(); /* sender channel */
+
+        Channel c = getChannel(id);
+
+        if(c == null) {
+            throw new PacketTypeException("Unexpected SSH_MSG_CHANNEL_OPEN_FAILURE message for non-existent channel " + id);
+        }
+
+        int reasonCode = tr.readUINT32();
+        String description = tr.readString("UTF-8");
+
+        String reasonCodeSymbolicName;
+
+        switch(reasonCode) {
+            case 1:
+                reasonCodeSymbolicName = "SSH_OPEN_ADMINISTRATIVELY_PROHIBITED";
+                break;
+            case 2:
+                reasonCodeSymbolicName = "SSH_OPEN_CONNECT_FAILED";
+                break;
+            case 3:
+                reasonCodeSymbolicName = "SSH_OPEN_UNKNOWN_CHANNEL_TYPE";
+                break;
+            case 4:
+                reasonCodeSymbolicName = "SSH_OPEN_RESOURCE_SHORTAGE";
+                break;
+            default:
+                reasonCodeSymbolicName = "UNKNOWN REASON CODE (" + reasonCode + ")";
+        }
+
+        StringBuilder descriptionBuffer = new StringBuilder();
+        descriptionBuffer.append(description);
+
+        for(int i = 0; i < descriptionBuffer.length(); i++) {
+            char cc = descriptionBuffer.charAt(i);
+
+            if((cc >= 32) && (cc <= 126)) {
+                continue;
+            }
+            descriptionBuffer.setCharAt(i, '\uFFFD');
+        }
+
+        synchronized(c) {
+            c.EOF = true;
+            c.state = Channel.STATE_CLOSED;
+            c.setReasonClosed(new ChannelClosedException(String.format("The server refused to open the channel (%s, '%s')",
+                    reasonCodeSymbolicName, descriptionBuffer.toString())));
+            c.notifyAll();
+        }
+
+        log.debug("Got SSH_MSG_CHANNEL_OPEN_FAILURE (channel " + id + ")");
+    }
+
+    public void msgGlobalRequest(byte[] msg) throws IOException {
+		/* Currently we do not support any kind of global request */
+
+        TypesReader tr = new TypesReader(msg);
+
+        tr.readByte(); // skip packet type
+        String requestName = tr.readString();
+        boolean wantReply = tr.readBoolean();
+
+        if(wantReply) {
+            byte[] reply_failure = new byte[1];
+            reply_failure[0] = Packets.SSH_MSG_REQUEST_FAILURE;
+
+            tm.sendAsynchronousMessage(reply_failure);
+        }
+
+		/* We do not clean up the requestName String - that is OK for debug */
+
+        log.debug("Got SSH_MSG_GLOBAL_REQUEST (" + requestName + ")");
+    }
+
+    public void msgGlobalSuccess() throws IOException {
+        synchronized(channels) {
+            globalSuccessCounter++;
+            channels.notifyAll();
+        }
+
+        log.debug("Got SSH_MSG_REQUEST_SUCCESS");
+    }
+
+    public void msgGlobalFailure() throws IOException {
+        synchronized(channels) {
+            globalFailedCounter++;
+            channels.notifyAll();
+        }
+
+        log.debug("Got SSH_MSG_REQUEST_FAILURE");
+    }
+
+    @Override
+    public void handleFailure(final IOException failure) {
+        log.debug("HandleMessage: got shutdown");
+
+        synchronized(listenerThreads) {
+            for(IChannelWorkerThread lat : listenerThreads) {
+                lat.stopWorking();
+            }
+            listenerThreadsAllowed = false;
+        }
+
+        synchronized(channels) {
+            shutdown = true;
+
+            for(Channel c : channels) {
+                synchronized(c) {
+                    c.EOF = true;
+                    c.state = Channel.STATE_CLOSED;
+                    c.setReasonClosed(failure);
+                    c.closeMessageRecv = true;
+                    c.notifyAll();
+                }
+            }
+            channels.clear();
+            channels.notifyAll(); /* Notify global response waiters */
+        }
+    }
+
+    public void handleMessage(byte[] msg) throws IOException {
+        switch(msg[0]) {
+            case Packets.SSH_MSG_CHANNEL_OPEN_CONFIRMATION:
+                msgChannelOpenConfirmation(msg);
+                break;
+            case Packets.SSH_MSG_CHANNEL_WINDOW_ADJUST:
+                msgChannelWindowAdjust(msg);
+                break;
+            case Packets.SSH_MSG_CHANNEL_DATA:
+                msgChannelData(msg);
+                break;
+            case Packets.SSH_MSG_CHANNEL_EXTENDED_DATA:
+                msgChannelExtendedData(msg);
+                break;
+            case Packets.SSH_MSG_CHANNEL_REQUEST:
+                msgChannelRequest(msg);
+                break;
+            case Packets.SSH_MSG_CHANNEL_EOF:
+                msgChannelEOF(msg);
+                break;
+            case Packets.SSH_MSG_CHANNEL_OPEN:
+                msgChannelOpen(msg);
+                break;
+            case Packets.SSH_MSG_CHANNEL_CLOSE:
+                msgChannelClose(msg);
+                break;
+            case Packets.SSH_MSG_CHANNEL_SUCCESS:
+                msgChannelSuccess(msg);
+                break;
+            case Packets.SSH_MSG_CHANNEL_FAILURE:
+                msgChannelFailure(msg);
+                break;
+            case Packets.SSH_MSG_CHANNEL_OPEN_FAILURE:
+                msgChannelOpenFailure(msg);
+                break;
+            case Packets.SSH_MSG_GLOBAL_REQUEST:
+                msgGlobalRequest(msg);
+                break;
+            case Packets.SSH_MSG_REQUEST_SUCCESS:
+                msgGlobalSuccess();
+                break;
+            case Packets.SSH_MSG_REQUEST_FAILURE:
+                msgGlobalFailure();
+                break;
+            default:
+                throw new PacketTypeException(msg[0]);
+        }
+    }
+}