| | | 1 | | using System; |
| | | 2 | | using System.Net; |
| | | 3 | | using System.Net.Sockets; |
| | | 4 | | using Renci.SshNet.Abstractions; |
| | | 5 | | using Renci.SshNet.Common; |
| | | 6 | | using Renci.SshNet.Messages.Connection; |
| | | 7 | | |
| | | 8 | | namespace Renci.SshNet.Channels |
| | | 9 | | { |
| | | 10 | | /// <summary> |
| | | 11 | | /// Implements "forwarded-tcpip" SSH channel. |
| | | 12 | | /// </summary> |
| | | 13 | | internal sealed class ChannelForwardedTcpip : ServerChannel, IChannelForwardedTcpip |
| | | 14 | | { |
| | 17 | 15 | | private readonly object _socketShutdownAndCloseLock = new object(); |
| | | 16 | | private Socket _socket; |
| | | 17 | | private IForwardedPort _forwardedPort; |
| | | 18 | | |
| | | 19 | | /// <summary> |
| | | 20 | | /// Initializes a new instance of the <see cref="ChannelForwardedTcpip"/> class. |
| | | 21 | | /// </summary> |
| | | 22 | | /// <param name="session">The session.</param> |
| | | 23 | | /// <param name="localChannelNumber">The local channel number.</param> |
| | | 24 | | /// <param name="localWindowSize">Size of the window.</param> |
| | | 25 | | /// <param name="localPacketSize">Size of the packet.</param> |
| | | 26 | | /// <param name="remoteChannelNumber">The remote channel number.</param> |
| | | 27 | | /// <param name="remoteWindowSize">The window size of the remote party.</param> |
| | | 28 | | /// <param name="remotePacketSize">The maximum size of a data packet that we can send to the remote party.</para |
| | | 29 | | internal ChannelForwardedTcpip(ISession session, |
| | | 30 | | uint localChannelNumber, |
| | | 31 | | uint localWindowSize, |
| | | 32 | | uint localPacketSize, |
| | | 33 | | uint remoteChannelNumber, |
| | | 34 | | uint remoteWindowSize, |
| | | 35 | | uint remotePacketSize) |
| | 17 | 36 | | : base(session, |
| | 17 | 37 | | localChannelNumber, |
| | 17 | 38 | | localWindowSize, |
| | 17 | 39 | | localPacketSize, |
| | 17 | 40 | | remoteChannelNumber, |
| | 17 | 41 | | remoteWindowSize, |
| | 17 | 42 | | remotePacketSize) |
| | 17 | 43 | | { |
| | 17 | 44 | | } |
| | | 45 | | |
| | | 46 | | /// <summary> |
| | | 47 | | /// Gets the type of the channel. |
| | | 48 | | /// </summary> |
| | | 49 | | /// <value> |
| | | 50 | | /// The type of the channel. |
| | | 51 | | /// </value> |
| | | 52 | | public override ChannelTypes ChannelType |
| | | 53 | | { |
| | 0 | 54 | | get { return ChannelTypes.ForwardedTcpip; } |
| | | 55 | | } |
| | | 56 | | |
| | | 57 | | /// <summary> |
| | | 58 | | /// Binds the channel to the specified endpoint. |
| | | 59 | | /// </summary> |
| | | 60 | | /// <param name="remoteEndpoint">The endpoint to connect to.</param> |
| | | 61 | | /// <param name="forwardedPort">The forwarded port for which the channel is opened.</param> |
| | | 62 | | public void Bind(IPEndPoint remoteEndpoint, IForwardedPort forwardedPort) |
| | 17 | 63 | | { |
| | 17 | 64 | | if (!IsConnected) |
| | 0 | 65 | | { |
| | 0 | 66 | | throw new SshException("Session is not connected."); |
| | | 67 | | } |
| | | 68 | | |
| | 17 | 69 | | _forwardedPort = forwardedPort; |
| | 17 | 70 | | _forwardedPort.Closing += ForwardedPort_Closing; |
| | | 71 | | |
| | | 72 | | // Try to connect to the socket |
| | | 73 | | try |
| | 17 | 74 | | { |
| | 17 | 75 | | _socket = SocketAbstraction.Connect(remoteEndpoint, ConnectionInfo.Timeout); |
| | | 76 | | |
| | | 77 | | // Send channel open confirmation message |
| | 17 | 78 | | SendMessage(new ChannelOpenConfirmationMessage(RemoteChannelNumber, LocalWindowSize, LocalPacketSize, Lo |
| | 17 | 79 | | } |
| | 0 | 80 | | catch (Exception exp) |
| | 0 | 81 | | { |
| | | 82 | | // Send channel open failure message |
| | 0 | 83 | | SendMessage(new ChannelOpenFailureMessage(RemoteChannelNumber, exp.ToString(), ChannelOpenFailureMessage |
| | | 84 | | |
| | 0 | 85 | | throw; |
| | | 86 | | } |
| | | 87 | | |
| | 17 | 88 | | var buffer = new byte[RemotePacketSize]; |
| | | 89 | | |
| | 17 | 90 | | SocketAbstraction.ReadContinuous(_socket, buffer, 0, buffer.Length, SendData); |
| | 17 | 91 | | } |
| | | 92 | | |
| | | 93 | | protected override void OnErrorOccured(Exception exp) |
| | 0 | 94 | | { |
| | 0 | 95 | | base.OnErrorOccured(exp); |
| | | 96 | | |
| | | 97 | | // signal to the server that we will not send anything anymore; this will also interrupt the |
| | | 98 | | // blocking receive in Bind if the server sends FIN/ACK in time |
| | | 99 | | // |
| | | 100 | | // if the FIN/ACK is not sent in time, the socket will be closed in Close(bool) |
| | 0 | 101 | | ShutdownSocket(SocketShutdown.Send); |
| | 0 | 102 | | } |
| | | 103 | | |
| | | 104 | | /// <summary> |
| | | 105 | | /// Occurs as the forwarded port is being stopped. |
| | | 106 | | /// </summary> |
| | | 107 | | private void ForwardedPort_Closing(object sender, EventArgs eventArgs) |
| | 2 | 108 | | { |
| | | 109 | | // signal to the server that we will not send anything anymore; this will also interrupt the |
| | | 110 | | // blocking receive in Bind if the server sends FIN/ACK in time |
| | | 111 | | // |
| | | 112 | | // if the FIN/ACK is not sent in time, the socket will be closed in Close(bool) |
| | 2 | 113 | | ShutdownSocket(SocketShutdown.Send); |
| | 2 | 114 | | } |
| | | 115 | | |
| | | 116 | | /// <summary> |
| | | 117 | | /// Shuts down the socket. |
| | | 118 | | /// </summary> |
| | | 119 | | /// <param name="how">One of the <see cref="SocketShutdown"/> values that specifies the operation that will no l |
| | | 120 | | private void ShutdownSocket(SocketShutdown how) |
| | 36 | 121 | | { |
| | 36 | 122 | | if (_socket is null) |
| | 0 | 123 | | { |
| | 0 | 124 | | return; |
| | | 125 | | } |
| | | 126 | | |
| | 36 | 127 | | lock (_socketShutdownAndCloseLock) |
| | 36 | 128 | | { |
| | 36 | 129 | | var socket = _socket; |
| | 36 | 130 | | if (!socket.IsConnected()) |
| | 19 | 131 | | { |
| | 19 | 132 | | return; |
| | | 133 | | } |
| | | 134 | | |
| | | 135 | | try |
| | 17 | 136 | | { |
| | 17 | 137 | | socket.Shutdown(how); |
| | 17 | 138 | | } |
| | 0 | 139 | | catch (SocketException ex) |
| | 0 | 140 | | { |
| | | 141 | | // TODO: log as warning |
| | 0 | 142 | | DiagnosticAbstraction.Log("Failure shutting down socket: " + ex); |
| | 0 | 143 | | } |
| | 17 | 144 | | } |
| | 36 | 145 | | } |
| | | 146 | | |
| | | 147 | | /// <summary> |
| | | 148 | | /// Closes the socket, hereby interrupting the blocking receive in <see cref="Bind(IPEndPoint,IForwardedPort)"/> |
| | | 149 | | /// </summary> |
| | | 150 | | private void CloseSocket() |
| | 34 | 151 | | { |
| | 34 | 152 | | if (_socket is null) |
| | 17 | 153 | | { |
| | 17 | 154 | | return; |
| | | 155 | | } |
| | | 156 | | |
| | 17 | 157 | | lock (_socketShutdownAndCloseLock) |
| | 17 | 158 | | { |
| | 17 | 159 | | var socket = _socket; |
| | 17 | 160 | | if (socket != null) |
| | 17 | 161 | | { |
| | 17 | 162 | | _socket = null; |
| | 17 | 163 | | socket.Dispose(); |
| | 17 | 164 | | } |
| | 17 | 165 | | } |
| | 34 | 166 | | } |
| | | 167 | | |
| | | 168 | | /// <summary> |
| | | 169 | | /// Closes the channel waiting for the SSH_MSG_CHANNEL_CLOSE message to be received from the server. |
| | | 170 | | /// </summary> |
| | | 171 | | protected override void Close() |
| | 34 | 172 | | { |
| | 34 | 173 | | var forwardedPort = _forwardedPort; |
| | 34 | 174 | | if (forwardedPort != null) |
| | 17 | 175 | | { |
| | 17 | 176 | | forwardedPort.Closing -= ForwardedPort_Closing; |
| | 17 | 177 | | _forwardedPort = null; |
| | 17 | 178 | | } |
| | | 179 | | |
| | | 180 | | // signal to the server that we will not send anything anymore; this will also interrupt the |
| | | 181 | | // blocking receive in Bind if the server sends FIN/ACK in time |
| | | 182 | | // |
| | | 183 | | // if the FIN/ACK is not sent in time, the socket will be closed after the channel is closed |
| | 34 | 184 | | ShutdownSocket(SocketShutdown.Send); |
| | | 185 | | |
| | | 186 | | // close the SSH channel, and mark the channel closed |
| | 34 | 187 | | base.Close(); |
| | | 188 | | |
| | | 189 | | // close the socket |
| | 34 | 190 | | CloseSocket(); |
| | 34 | 191 | | } |
| | | 192 | | |
| | | 193 | | /// <summary> |
| | | 194 | | /// Called when channel data is received. |
| | | 195 | | /// </summary> |
| | | 196 | | /// <param name="data">The data.</param> |
| | | 197 | | protected override void OnData(byte[] data) |
| | 2 | 198 | | { |
| | 2 | 199 | | base.OnData(data); |
| | | 200 | | |
| | 2 | 201 | | var socket = _socket; |
| | 2 | 202 | | if (socket.IsConnected()) |
| | 2 | 203 | | { |
| | 2 | 204 | | SocketAbstraction.Send(socket, data, 0, data.Length); |
| | 2 | 205 | | } |
| | 2 | 206 | | } |
| | | 207 | | } |
| | | 208 | | } |