Package com.sshtools.synergy.ssh

Class SocketForwardingChannel<T extends SshContext>

java.lang.Object

com.sshtools.synergy.ssh.ChannelNG<T>

com.sshtools.synergy.ssh.ForwardingChannel<T>

com.sshtools.synergy.ssh.SocketForwardingChannel<T>

All Implemented Interfaces:

Channel, SelectionKeyAware, SelectorRegistrationListener, SocketHandler

Direct Known Subclasses:

LocalForwardingChannel, RemoteForwardingChannel

public abstract class SocketForwardingChannel<T extends SshContext>
extends ForwardingChannel<T>
implements SocketHandler

An abstract forwarding channel implementation for use with forwarding both local and remote sockets.

See Also:

• ForwardingChannel

Nested Class Summary

Nested classes/interfaces inherited from class com.sshtools.synergy.ssh.ChannelNG

ChannelNG.ChannelInputStream

Field Summary

Fields

Modifier and Type	Field	Description
protected SelectionKey	key
static final String	LOCAL_FORWARDING_CHANNEL_TYPE
static final String	REMOTE_FORWARDING_CHANNEL_TYPE
protected SelectorThread	selectorThread
protected SocketChannel	socketChannel
static final String	X11_FORWARDING_CHANNEL_TYPE

Fields inherited from class com.sshtools.synergy.ssh.ForwardingChannel

hostToConnect, originatingHost, originatingPort, portToConnect

Fields inherited from class com.sshtools.synergy.ssh.ChannelNG

cache, con, connection, localWindow, remoteWindow

Constructor Summary

Constructors

Constructor	Description
SocketForwardingChannel(String channeltype, SshConnection con)	Construct the forwarding channel.

Method Summary

Modifier and Type	Method	Description
void	addTask(ConnectionAwareTask task)	Add a task to the executor
protected boolean	canClose()	Can this channel close?
protected void	cleanupSocket()
protected CachingDataWindow	createCache(int maximumWindowSpace)
protected abstract byte[]	createChannel()	Called when the channel is being created.
protected void	evaluateClosure()	set the closePending flag to true and attempt to close the channel
protected void	evaluateWindowSpace(int remaining)
int	getInitialOps()	Returns the current operations the handler is interested in
String	getName()	A name for this Socket
SelectorThread	getSelectorThread()	Get the selector thread this handler is connected to.
void	initialize(ProtocolEngine engine, SshEngine daemon)	No initialisation is necessary so this method does nothing.
protected void	onChannelClosed()	Called when the channel has been closed to enable resources to be freed.
protected void	onChannelClosing()	does nothing
protected void	onChannelData(ByteBuffer data)	data has arrived from the end of the tunnel so add to the queue of data heading towards the start of the tunnel
protected void	onChannelFree()	does nothing
protected void	onChannelOpen()	does nothing
protected abstract void	onChannelOpenConfirmation()	Called when the channel has been confirmed as open by the remote side - this method is only called when the channel has been requested by this side of the connection
protected void	onChannelRequest(String parm1, boolean parm2, byte[] parm3)	Called when a channel request is received.
protected void	onExtendedData(ByteBuffer data, int type)	does nothing
protected void	onLocalEOF()	The start of the tunnel has gone EOF , if the end of the tunnel has already gone EOF then close the tunnel.
protected abstract void	onRegistrationComplete()	Called by the subsystem when the selector registration has been completed.
protected void	onRemoteClose()	We override this to make sure that all data from the socket has been sent before we close our side of the channel
protected void	onRemoteEOF()	The end of the tunnel has gone EOF , if the start of the tunnel has already gone EOF then close the tunnel.
protected abstract byte[]	openChannel(byte[] parm1)	Called when the channel is being opened.
boolean	processReadEvent()	read data from the start/end of tunnel and write it into the ssh tunnel.
boolean	processWriteEvent()	read data from the ssh tunnel and write it to the start/end point.
void	registrationCompleted(SelectableChannel channel, SelectionKey key, SelectorThread selectorThread)	The registration completed and its selector added to an available SelectorThread
void	setSelectionKey(SelectionKey key)
void	setThread(SelectorThread thread)	Sets the selector thread for this connection
protected void	shutdownSocket()
boolean	wantsRead()	Tell the selector that the handler wants to read.
boolean	wantsWrite()	Tell the selector that the handler wants to write.

Methods inherited from class com.sshtools.synergy.ssh.ForwardingChannel

getHost, getOriginatingHost, getOriginatingPort, getPort

Methods inherited from class com.sshtools.synergy.ssh.ChannelNG

addEventListener, checkWindowSpace, clearIdleState, close, close, close, disposeCache, evaluateWindowSpace, getChannelType, getCloseFuture, getConnection, getConnectionProtocol, getContext, getInputStream, getLastActivity, getLocalId, getLocalPacket, getLocalWindow, getMaxiumRemotePacketSize, getMaxiumRemoteWindowSize, getOpenFuture, getOutputStream, getRemoteId, getRemotePacket, getRemoteWindow, getSessionIdentifier, getTimeout, haltIncomingData, isAutoConsume, isClosed, isClosing, isConnected, isIncomingDataHalted, isLocalEOF, isOpen, isRemoteEOF, log, log, log, log, logMessage, logMessage, onChannelError, onChannelOpenFailure, onWindowAdjust, processChannelRequestResponse, registerExtendedDataType, resetIdleState, resumeIncomingData, sendChannelDataAndBlock, sendChannelDataAndBlock, sendChannelDataAndBlock, sendChannelDataAndBlock, sendChannelDataAndBlock, sendChannelDataAndBlock, sendChannelRequest, sendChannelRequest, sendData, sendEOF, sendExtendedData, sendExtendedData, sendRequestResponse, sendWindowAdjust, sendWindowAdjust, setTimeout

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface com.sshtools.synergy.nio.SocketHandler

getConnection, getContext, initialize

Field Details

LOCAL_FORWARDING_CHANNEL_TYPE

public static final String LOCAL_FORWARDING_CHANNEL_TYPE

See Also:

• Constant Field Values

REMOTE_FORWARDING_CHANNEL_TYPE

public static final String REMOTE_FORWARDING_CHANNEL_TYPE

See Also:

• Constant Field Values

X11_FORWARDING_CHANNEL_TYPE

public static final String X11_FORWARDING_CHANNEL_TYPE

See Also:

• Constant Field Values

socketChannel

protected SocketChannel socketChannel

selectorThread

protected SelectorThread selectorThread

key

protected SelectionKey key

Constructor Details

SocketForwardingChannel

public SocketForwardingChannel(String channeltype,
 SshConnection con)

Construct the forwarding channel.

Parameters:

channeltype - the type of channel i.e. "forwarded-tcpip"

Method Details

createCache

protected CachingDataWindow createCache(int maximumWindowSpace)

Overrides:

createCache in class ChannelNG<T extends SshContext>

setSelectionKey

public void setSelectionKey(SelectionKey key)

Specified by:

setSelectionKey in interface SelectionKeyAware

onChannelOpen

protected void onChannelOpen()

does nothing

Specified by:

onChannelOpen in class ChannelNG<T extends SshContext>

initialize

public void initialize(ProtocolEngine engine,
 SshEngine daemon)

No initialisation is necessary so this method does nothing.

createChannel

protected abstract byte[] createChannel()
                                 throws IOException

Description copied from class: ChannelNG

Called when the channel is being created. You can return data to be sent in the channel open request, or null for none.

Specified by:

createChannel in class ChannelNG<T extends SshContext>

Returns:

byte[]

Throws:

IOException

onExtendedData

protected void onExtendedData(ByteBuffer data,
 int type)

does nothing

Overrides:

onExtendedData in class ChannelNG<T extends SshContext>

onRegistrationComplete

protected abstract void onRegistrationComplete()

Called by the subsystem when the selector registration has been completed.

registrationCompleted

public void registrationCompleted(SelectableChannel channel,
 SelectionKey key,
 SelectorThread selectorThread)

Description copied from interface: SelectorRegistrationListener

The registration completed and its selector added to an available SelectorThread

Specified by:

registrationCompleted in interface SelectorRegistrationListener

Parameters:

channel - SelectableChannel

key - SelectionKey

selectorThread - SelectorThread

onChannelData

protected void onChannelData(ByteBuffer data)

data has arrived from the end of the tunnel so add to the queue of data heading towards the start of the tunnel

Overrides:

onChannelData in class ChannelNG<T extends SshContext>

onChannelRequest

protected void onChannelRequest(String parm1,
 boolean parm2,
 byte[] parm3)

Description copied from class: ChannelNG

Called when a channel request is received.

Specified by:

onChannelRequest in class ChannelNG<T extends SshContext>

onChannelFree

protected void onChannelFree()

does nothing

Specified by:

onChannelFree in class ChannelNG<T extends SshContext>

onChannelClosing

protected void onChannelClosing()

does nothing

Specified by:

onChannelClosing in class ChannelNG<T extends SshContext>

cleanupSocket

protected void cleanupSocket()

canClose

protected boolean canClose()

Description copied from class: ChannelNG

Can this channel close?

Overrides:

canClose in class ChannelNG<T extends SshContext>

Returns:

true if there is no queued data, else false

evaluateClosure

protected void evaluateClosure()

set the closePending flag to true and attempt to close the channel

shutdownSocket

protected void shutdownSocket()

onChannelClosed

protected void onChannelClosed()

Description copied from class: ChannelNG

Called when the channel has been closed to enable resources to be freed.

Specified by:

onChannelClosed in class ChannelNG<T extends SshContext>

onLocalEOF

protected void onLocalEOF()

The start of the tunnel has gone EOF , if the end of the tunnel has already gone EOF then close the tunnel.

Specified by:

onLocalEOF in class ChannelNG<T extends SshContext>

onRemoteClose

protected void onRemoteClose()

We override this to make sure that all data from the socket has been sent before we close our side of the channel

Overrides:

onRemoteClose in class ChannelNG<T extends SshContext>

onRemoteEOF

protected void onRemoteEOF()

The end of the tunnel has gone EOF , if the start of the tunnel has already gone EOF then close the tunnel.

Specified by:

onRemoteEOF in class ChannelNG<T extends SshContext>

onChannelOpenConfirmation

protected abstract void onChannelOpenConfirmation()

Description copied from class: ChannelNG

Called when the channel has been confirmed as open by the remote side - this method is only called when the channel has been requested by this side of the connection

Specified by:

onChannelOpenConfirmation in class ChannelNG<T extends SshContext>

evaluateWindowSpace

protected void evaluateWindowSpace(int remaining)

openChannel

protected abstract byte[] openChannel(byte[] parm1)
                               throws WriteOperationRequest,
ChannelOpenException

Description copied from class: ChannelNG

Called when the channel is being opened. You can retrun data to be sent in the channel open confirmation message, or null for none.

Specified by:

openChannel in class ChannelNG<T extends SshContext>

Returns:

byte[]

Throws:

WriteOperationRequest

ChannelOpenException

processReadEvent

public boolean processReadEvent()

read data from the start/end of tunnel and write it into the ssh tunnel.

Specified by:

processReadEvent in interface SocketHandler

Returns:

boolean indicating ??

processWriteEvent

public boolean processWriteEvent()

read data from the ssh tunnel and write it to the start/end point.

Specified by:

processWriteEvent in interface SocketHandler

Returns:

boolean

wantsWrite

public boolean wantsWrite()

Description copied from interface: SocketHandler

Tell the selector that the handler wants to write.

Specified by:

wantsWrite in interface SocketHandler

Returns:

wantsRead

public boolean wantsRead()

Description copied from interface: SocketHandler

Tell the selector that the handler wants to read.

Specified by:

wantsRead in interface SocketHandler

Returns:

getInitialOps

public int getInitialOps()

Description copied from interface: SocketHandler

Returns the current operations the handler is interested in

Specified by:

getInitialOps in interface SocketHandler

Returns:

int

setThread

public void setThread(SelectorThread thread)

Sets the selector thread for this connection

Specified by:

setThread in interface SocketHandler

Parameters:

thread - SelectorThread

addTask

public void addTask(ConnectionAwareTask task)

Description copied from interface: SocketHandler

Add a task to the executor

Specified by:

addTask in interface SocketHandler

getSelectorThread

public SelectorThread getSelectorThread()

Description copied from interface: SocketHandler

Get the selector thread this handler is connected to.

Specified by:

getSelectorThread in interface SocketHandler

Returns:

getName

public String getName()

Description copied from interface: SocketHandler

A name for this Socket

Specified by:

getName in interface SocketHandler

Returns: