/// <summary>
/// Process packet about this channel.
/// </summary>
/// <param name="packetType">a packet type (message number)</param>
/// <param name="packetFragment">a packet image except message number and recipient channel.</param>
public void ProcessPacket(SSH2PacketType packetType, DataFragment packetFragment)
{
if (_state == State.Closed) {
return; // ignore
}
DataFragment dataFragmentArg;
uint dataTypeCodeArg;
lock (_stateSync) {
switch (_state) {
case State.InitiatedByServer:
break;
case State.InitiatedByClient:
if (packetType == SSH2PacketType.SSH_MSG_CHANNEL_OPEN_CONFIRMATION) {
SSH2DataReader reader = new SSH2DataReader(packetFragment);
RemoteChannel = reader.ReadUInt32();
_serverWindowSizeLeft = reader.ReadUInt32();
_serverMaxPacketSize = reader.ReadUInt32();
_state = State.Established;
Monitor.PulseAll(_stateSync); // notifies state change
dataFragmentArg = reader.GetRemainingDataView();
goto OnEstablished; // do it out of the lock block
}
if (packetType == SSH2PacketType.SSH_MSG_CHANNEL_OPEN_FAILURE) {
SSH2DataReader reader = new SSH2DataReader(packetFragment);
uint reasonCode = reader.ReadUInt32();
string description = reader.ReadUTF8String();
string lang = reader.ReadString();
goto RequestFailed; // do it out of the lock block
}
break;
case State.Closing:
if (packetType == SSH2PacketType.SSH_MSG_CHANNEL_CLOSE) {
goto SetStateClosedByClient; // do it out of the lock block
}
break;
case State.Established:
case State.Ready:
if (ProcessPacketSub(packetType, packetFragment) == SubPacketProcessResult.Consumed) {
return;
}
switch (packetType) {
case SSH2PacketType.SSH_MSG_CHANNEL_DATA: {
SSH2DataReader reader = new SSH2DataReader(packetFragment);
int len = reader.ReadInt32();
dataFragmentArg = reader.GetRemainingDataView(len);
AdjustWindowSize(len);
}
goto OnData; // do it out of the lock block
case SSH2PacketType.SSH_MSG_CHANNEL_EXTENDED_DATA: {
SSH2DataReader reader = new SSH2DataReader(packetFragment);
dataTypeCodeArg = reader.ReadUInt32();
int len = reader.ReadInt32();
dataFragmentArg = reader.GetRemainingDataView(len);
AdjustWindowSize(len);
}
goto OnExtendedData; // do it out of the lock block
case SSH2PacketType.SSH_MSG_CHANNEL_REQUEST: {
SSH2DataReader reader = new SSH2DataReader(packetFragment);
string request = reader.ReadString();
bool wantReply = reader.ReadBool();
if (wantReply) { //we reject unknown requests including keep-alive check
Transmit(
0,
new SSH2Packet(SSH2PacketType.SSH_MSG_CHANNEL_FAILURE)
.WriteUInt32(RemoteChannel)
);
}
}
break;
case SSH2PacketType.SSH_MSG_CHANNEL_EOF:
goto OnEOF; // do it out of the lock block
case SSH2PacketType.SSH_MSG_CHANNEL_CLOSE:
Transmit(
0,
new SSH2Packet(SSH2PacketType.SSH_MSG_CHANNEL_CLOSE)
.WriteUInt32(RemoteChannel)
);
goto SetStateClosedByServer; // do it out of the lock block
case SSH2PacketType.SSH_MSG_CHANNEL_WINDOW_ADJUST: {
SSH2DataReader reader = new SSH2DataReader(packetFragment);
uint bytesToAdd = reader.ReadUInt32();
// some servers may not send SSH_MSG_CHANNEL_WINDOW_ADJUST.
// it is dangerous to wait this message in send procedure
_serverWindowSizeLeft += bytesToAdd;
}
goto OnWindowAdjust;
case SSH2PacketType.SSH_MSG_CHANNEL_SUCCESS:
case SSH2PacketType.SSH_MSG_CHANNEL_FAILURE: {
_channelRequestResult.TrySet(packetType == SSH2PacketType.SSH_MSG_CHANNEL_SUCCESS, 1000);
}
break;
default:
goto OnUnhandledPacket;
}
break; // case State.Ready
}
}
return;
OnEstablished:
_protocolEventManager.Trace(
"CH[{0}] remoteCH={1} remoteWindowSize={2} remoteMaxPacketSize={3}",
LocalChannel, RemoteChannel, _serverWindowSizeLeft, _serverMaxPacketSize);
_handler.OnEstablished(dataFragmentArg);
OnChannelEstablished();
return;
RequestFailed:
_protocolEventManager.Trace("CH[{0}] request failed", LocalChannel);
RequestFailed();
return;
SetStateClosedByClient:
_protocolEventManager.Trace("CH[{0}] closed completely", LocalChannel);
SetStateClosed(false);
return;
SetStateClosedByServer:
_protocolEventManager.Trace("CH[{0}] closed by server", LocalChannel);
SetStateClosed(true);
return;
OnData:
_handler.OnData(dataFragmentArg);
return;
OnExtendedData:
_handler.OnExtendedData(dataTypeCodeArg, dataFragmentArg);
return;
OnEOF:
_protocolEventManager.Trace("CH[{0}] caught EOF", LocalChannel);
_handler.OnEOF();
return;
OnWindowAdjust:
_protocolEventManager.Trace(
"CH[{0}] adjusted remote window size to {1}",
LocalChannel, _serverWindowSizeLeft);
return;
OnUnhandledPacket:
_handler.OnUnhandledPacket((byte)packetType, packetFragment);
return;
}
private void ProcessChannelLocalData(ISSHChannelEventReceiver receiver, SSH2PacketType pt, SSH2DataReader re)
{
switch (pt) {
case SSH2PacketType.SSH_MSG_CHANNEL_DATA: {
int len = re.ReadInt32();
DataFragment frag = re.GetRemainingDataView(len);
receiver.OnData(frag.Data, frag.Offset, frag.Length);
}
break;
case SSH2PacketType.SSH_MSG_CHANNEL_EXTENDED_DATA: {
int t = re.ReadInt32();
byte[] data = re.ReadByteString();
receiver.OnExtendedData(t, data);
}
break;
case SSH2PacketType.SSH_MSG_CHANNEL_REQUEST: {
string request = re.ReadString();
bool reply = re.ReadBool();
if (request == "exit-status") {
int status = re.ReadInt32();
}
else if (reply) { //we reject unknown requests including keep-alive check
Transmit(
0,
new SSH2Packet(SSH2PacketType.SSH_MSG_CHANNEL_FAILURE)
.WriteInt32(_remoteID)
);
}
}
break;
case SSH2PacketType.SSH_MSG_CHANNEL_EOF:
receiver.OnChannelEOF();
break;
case SSH2PacketType.SSH_MSG_CHANNEL_CLOSE:
_connection.ChannelCollection.UnregisterChannelEventReceiver(_localID);
receiver.OnChannelClosed();
break;
case SSH2PacketType.SSH_MSG_CHANNEL_FAILURE: {
DataFragment frag = re.GetRemainingDataView();
receiver.OnMiscPacket((byte)pt, frag.Data, frag.Offset, frag.Length);
}
break;
default: {
DataFragment frag = re.GetRemainingDataView();
receiver.OnMiscPacket((byte)pt, frag.Data, frag.Offset, frag.Length);
}
Debug.WriteLine("Unknown Packet " + pt);
break;
}
}
