twisted.conch.ssh.connection.SSHConnection : API documentation

An implementation of the 'ssh-connection' service. It is used to multiplex multiple channels over the single SSH connection.

Instance Variables	localChannelID	the next number to use as a local channel ID. (type: `int` )
	channels	a `dict` mapping a local channel ID to `SSHChannel` subclasses. (type: `dict` )
	localToRemoteChannel	a `dict` mapping a local channel ID to a remote channel ID. (type: `dict` )
	channelsToRemoteChannel	a `dict` mapping a `SSHChannel` subclass to remote channel ID. (type: `dict` )
	deferreds	a `dict` mapping a local channel ID to a `list` of `Deferreds` for outstanding channel requests. Also, the 'global' key stores the `list` of pending global request `Deferred`s.

Method	__init__	Undocumented
Method	serviceStarted	called when the service is active on the transport.
Method	serviceStopped	Called when the connection is stopped.
Method	ssh_GLOBAL_REQUEST	No summary
Method	ssh_REQUEST_SUCCESS	Our global request succeeded. Get the appropriate Deferred and call it back with the packet we received.
Method	ssh_REQUEST_FAILURE	Our global request failed. Get the appropriate Deferred and errback it with the packet we received.
Method	ssh_CHANNEL_OPEN	No summary
Method	ssh_CHANNEL_OPEN_CONFIRMATION	No summary
Method	ssh_CHANNEL_OPEN_FAILURE	No summary
Method	ssh_CHANNEL_WINDOW_ADJUST	The other side is adding bytes to its window. Payload:: uint32 local channel number uint32 bytes to add
Method	ssh_CHANNEL_DATA	The other side is sending us data. Payload:: uint32 local channel number string data
Method	ssh_CHANNEL_EXTENDED_DATA	No summary
Method	ssh_CHANNEL_EOF	The other side is not sending any more data. Payload:: uint32 local channel number
Method	ssh_CHANNEL_CLOSE	The other side is closing its end; it does not want to receive any more data. Payload:: uint32 local channel number
Method	ssh_CHANNEL_REQUEST	No summary
Method	ssh_CHANNEL_SUCCESS	Our channel request to the other other side succeeded. Payload:: uint32 local channel number
Method	ssh_CHANNEL_FAILURE	Our channel request to the other side failed. Payload:: uint32 local channel number
Method	sendGlobalRequest	Send a global request for this connection. Current this is only used for remote->local TCP forwarding.
Method	openChannel	Open a new channel on this connection.
Method	sendRequest	Send a request to a channel.
Method	adjustWindow	Tell the other side that we will receive more data. This should not normally need to be called as it is managed automatically.
Method	sendData	Send data to a channel. This should not normally be used: instead use channel.write(data) as it manages the window automatically.
Method	sendExtendedData	Send extended data to a channel. This should not normally be used: instead use channel.writeExtendedData(data, dataType) as it manages the window automatically.
Method	sendEOF	Send an EOF (End of File) for a channel.
Method	sendClose	Close a channel.
Method	getChannel	No summary
Method	gotGlobalRequest	No summary
Method	channelClosed	No summary
Method	_cleanupGlobalDeferreds	All pending requests that have returned a deferred must be errbacked when this service is stopped, otherwise they might be left uncalled and uncallable.
Method	_cbChannelRequest	Called back if the other side wanted a reply to a channel request. If the result is true, send a MSG_CHANNEL_SUCCESS. Otherwise, raise a `error.ConchError`
Method	_ebChannelRequest	Called if the other wisde wanted a reply to the channel requeset and the channel request failed.

Inherited from SSHService:

Method	logPrefix	Override this method to insert custom logging behavior. Its return value will be inserted in front of every line. It may be called more times than the number of output lines.
Method	packetReceived	called when we receive a packet on the transport

called when the service is active on the transport.

Called when the connection is stopped.

All pending requests that have returned a deferred must be errbacked when this service is stopped, otherwise they might be left uncalled and uncallable.

The other side has made a global request. Payload:

   string  request type
   bool    want reply
   <request specific data>

This dispatches to self.gotGlobalRequest.

Our global request succeeded. Get the appropriate Deferred and call it back with the packet we received.

Our global request failed. Get the appropriate Deferred and errback it with the packet we received.

The other side wants to get a channel. Payload:

   string  channel name
   uint32  remote channel number
   uint32  remote window size
   uint32  remote maximum packet size
   <channel specific data>

We get a channel from self.getChannel(), give it a local channel number and notify the other side. Then notify the channel by calling its channelOpen method.

The other side accepted our MSG_CHANNEL_OPEN request. Payload:

   uint32  local channel number
   uint32  remote channel number
   uint32  remote window size
   uint32  remote maximum packet size
   <channel specific data>

Find the channel using the local channel number and notify its channelOpen method.

The other side did not accept our MSG_CHANNEL_OPEN request. Payload:

   uint32  local channel number
   uint32  reason code
   string  reason description

Find the channel using the local channel number and notify it by calling its openFailed() method.

The other side is adding bytes to its window. Payload:

   uint32  local channel number
   uint32  bytes to add

Call the channel's addWindowBytes() method to add new bytes to the remote window.

The other side is sending us data. Payload:

   uint32 local channel number
   string data

Check to make sure the other side hasn't sent too much data (more than what's in the window, or more than the maximum packet size). If they have, close the channel. Otherwise, decrease the available window and pass the data to the channel's dataReceived().

The other side is sending us exteneded data. Payload:

   uint32  local channel number
   uint32  type code
   string  data

Check to make sure the other side hasn't sent too much data (more than what's in the window, or or than the maximum packet size). If they have, close the channel. Otherwise, decrease the available window and pass the data and type code to the channel's extReceived().

The other side is not sending any more data. Payload:

   uint32  local channel number

Notify the channel by calling its eofReceived() method.

The other side is closing its end; it does not want to receive any more data. Payload:

   uint32  local channel number

Notify the channnel by calling its closeReceived() method. If the channel has also sent a close message, call self.channelClosed().

The other side is sending a request to a channel. Payload:

   uint32  local channel number
   string  request name
   bool    want reply
   <request specific data>

Pass the message to the channel's requestReceived method. If the other side wants a reply, add callbacks which will send the reply.

Called back if the other side wanted a reply to a channel request. If the result is true, send a MSG_CHANNEL_SUCCESS. Otherwise, raise a error.ConchError

Parameters	result	the value returned from the channel's requestReceived() method. If it's False, the request failed. (type: `bool` )
	localChannel	the local channel ID of the channel to which the request was made. (type: `int` )
Raises	ConchError	if the result is False.

Called if the other wisde wanted a reply to the channel requeset and the channel request failed.

Parameters	result	a Failure, but it's not used.
	localChannel	the local channel ID of the channel to which the request was made. (type: `int` )

Our channel request to the other other side succeeded. Payload:

   uint32  local channel number

Get the Deferred out of self.deferreds and call it back.

Our channel request to the other side failed. Payload:

   uint32  local channel number

Get the Deferred out of self.deferreds and errback it with a error.ConchError.

Send a global request for this connection. Current this is only used for remote->local TCP forwarding.

Parameters	request	(type: `str` )
	data	(type: `str` )
	wantReply	(type: `bool` @rtype `Deferred`/`None` )

Open a new channel on this connection.

Parameters	channel	(type: subclass of `SSHChannel` )
	extra	(type: `str` )

Send a request to a channel.

Parameters	channel	(type: subclass of `SSHChannel` )
	requestType	(type: `str` )
	data	(type: `str` )
	wantReply	(type: `bool` @rtype `Deferred`/`None` )

Tell the other side that we will receive more data. This should not normally need to be called as it is managed automatically.

Parameters	channel	(type: subclass of `SSHChannel` )
	bytesToAdd	(type: `int` )

Send data to a channel. This should not normally be used: instead use channel.write(data) as it manages the window automatically.

Parameters	channel	(type: subclass of `SSHChannel` )
	data	(type: `str` )

Send extended data to a channel. This should not normally be used: instead use channel.writeExtendedData(data, dataType) as it manages the window automatically.

Parameters	channel	(type: subclass of `SSHChannel` )
	dataType	(type: `int` )
	data	(type: `str` )

Send an EOF (End of File) for a channel.

Parameters channel (type: subclass of SSHChannel )

Close a channel.

Parameters channel (type: subclass of SSHChannel )

The other side requested a channel of some sort. channelType is the type of channel being requested, windowSize is the initial size of the remote window, maxPacket is the largest packet we should send, data is any other packet data (often nothing).

We return a subclass of SSHChannel.

By default, this dispatches to a method 'channel_channelType' with any non-alphanumerics in the channelType replace with _'s. If it cannot find a suitable method, it returns an OPEN_UNKNOWN_CHANNEL_TYPE error. The method is called with arguments of windowSize, maxPacket, data.

Parameters	channelType	(type: `str` )
	windowSize	(type: `int` )
	maxPacket	(type: `int` )
	data	(type: `str` )
Returns	(type: subclass of `SSHChannel`/`tuple` )

We got a global request. pretty much, this is just used by the client to request that we forward a port from the server to the client. Returns either:

1: request accepted
1, <data>: request accepted with request specific data
0: request denied

By default, this dispatches to a method 'global_requestType' with -'s in requestType replaced with _'s. The found method is passed data. If this method cannot be found, this method returns 0. Otherwise, it returns the return value of that method.

Parameters	requestType	(type: `str` )
	data	(type: `str` )
Returns	(type: `int`/`tuple` )

Called when a channel is closed. It clears the local state related to the channel, and calls channel.closed(). MAKE SURE YOU CALL THIS METHOD, even if you subclass SSHConnection. If you don't, things will break mysteriously.

Parameters channel (type: SSHChannel )

t.c.s.c.SSHConnection(service.SSHService) : class documentation