Files
PepperDashCore/src/Comm/GenericSshClient.cs
2025-03-05 10:36:35 -06:00

593 lines
20 KiB
C#

using System;
using System.Text;
using System.Threading;
using Crestron.SimplSharp;
using Crestron.SimplSharp.CrestronSockets;
using Org.BouncyCastle.Utilities;
using PepperDash.Core.Logging;
using Renci.SshNet;
using Renci.SshNet.Common;
namespace PepperDash.Core
{
/// <summary>
///
/// </summary>
public class GenericSshClient : Device, ISocketStatusWithStreamDebugging, IAutoReconnect
{
private const string SPlusKey = "Uninitialized SshClient";
/// <summary>
/// Object to enable stream debugging
/// </summary>
public CommunicationStreamDebugging StreamDebugging { get; private set; }
/// <summary>
/// Event that fires when data is received. Delivers args with byte array
/// </summary>
public event EventHandler<GenericCommMethodReceiveBytesArgs> BytesReceived;
/// <summary>
/// Event that fires when data is received. Delivered as text.
/// </summary>
public event EventHandler<GenericCommMethodReceiveTextArgs> TextReceived;
/// <summary>
/// Event when the connection status changes.
/// </summary>
public event EventHandler<GenericSocketStatusChageEventArgs> ConnectionChange;
///// <summary>
/////
///// </summary>
//public event GenericSocketStatusChangeEventDelegate SocketStatusChange;
/// <summary>
/// Address of server
/// </summary>
public string Hostname { get; set; }
/// <summary>
/// Port on server
/// </summary>
public int Port { get; set; }
/// <summary>
/// Username for server
/// </summary>
public string Username { get; set; }
/// <summary>
/// And... Password for server. That was worth documenting!
/// </summary>
public string Password { get; set; }
/// <summary>
/// True when the server is connected - when status == 2.
/// </summary>
public bool IsConnected
{
// returns false if no client or not connected
get { return Client != null && ClientStatus == SocketStatus.SOCKET_STATUS_CONNECTED; }
}
/// <summary>
/// S+ helper for IsConnected
/// </summary>
public ushort UIsConnected
{
get { return (ushort)(IsConnected ? 1 : 0); }
}
/// <summary>
///
/// </summary>
public SocketStatus ClientStatus
{
get { return _ClientStatus; }
private set
{
if (_ClientStatus == value)
return;
_ClientStatus = value;
OnConnectionChange();
}
}
SocketStatus _ClientStatus;
/// <summary>
/// Contains the familiar Simpl analog status values. This drives the ConnectionChange event
/// and IsConnected with be true when this == 2.
/// </summary>
public ushort UStatus
{
get { return (ushort)_ClientStatus; }
}
/// <summary>
/// Determines whether client will attempt reconnection on failure. Default is true
/// </summary>
public bool AutoReconnect { get; set; }
/// <summary>
/// Will be set and unset by connect and disconnect only
/// </summary>
public bool ConnectEnabled { get; private set; }
/// <summary>
/// S+ helper for AutoReconnect
/// </summary>
public ushort UAutoReconnect
{
get { return (ushort)(AutoReconnect ? 1 : 0); }
set { AutoReconnect = value == 1; }
}
/// <summary>
/// Millisecond value, determines the timeout period in between reconnect attempts.
/// Set to 5000 by default
/// </summary>
public int AutoReconnectIntervalMs { get; set; }
SshClient Client;
ShellStream TheStream;
CTimer ReconnectTimer;
//Lock object to prevent simulatneous connect/disconnect operations
//private CCriticalSection connectLock = new CCriticalSection();
private SemaphoreSlim connectLock = new SemaphoreSlim(1);
private bool DisconnectLogged = false;
/// <summary>
/// Typical constructor.
/// </summary>
public GenericSshClient(string key, string hostname, int port, string username, string password) :
base(key)
{
StreamDebugging = new CommunicationStreamDebugging(key);
CrestronEnvironment.ProgramStatusEventHandler += new ProgramStatusEventHandler(CrestronEnvironment_ProgramStatusEventHandler);
Key = key;
Hostname = hostname;
Port = port;
Username = username;
Password = password;
AutoReconnectIntervalMs = 5000;
ReconnectTimer = new CTimer(o =>
{
if (ConnectEnabled)
{
Connect();
}
}, System.Threading.Timeout.Infinite);
}
/// <summary>
/// S+ Constructor - Must set all properties before calling Connect
/// </summary>
public GenericSshClient()
: base(SPlusKey)
{
CrestronEnvironment.ProgramStatusEventHandler += new ProgramStatusEventHandler(CrestronEnvironment_ProgramStatusEventHandler);
AutoReconnectIntervalMs = 5000;
ReconnectTimer = new CTimer(o =>
{
if (ConnectEnabled)
{
Connect();
}
}, System.Threading.Timeout.Infinite);
}
/// <summary>
/// Handles closing this up when the program shuts down
/// </summary>
void CrestronEnvironment_ProgramStatusEventHandler(eProgramStatusEventType programEventType)
{
if (programEventType == eProgramStatusEventType.Stopping)
{
if (Client != null)
{
this.LogDebug("Program stopping. Closing connection");
Disconnect();
}
}
}
/// <summary>
/// Connect to the server, using the provided properties.
/// </summary>
public void Connect()
{
// Don't go unless everything is here
if (string.IsNullOrEmpty(Hostname) || Port < 1 || Port > 65535
|| Username == null || Password == null)
{
this.LogError("Connect failed. Check hostname, port, username and password are set or not null");
return;
}
ConnectEnabled = true;
try
{
connectLock.Wait();
if (IsConnected)
{
this.LogDebug("Connection already connected. Exiting Connect");
}
else
{
this.LogDebug("Attempting connect");
// Cancel reconnect if running.
if (ReconnectTimer != null)
{
ReconnectTimer.Stop();
}
// Cleanup the old client if it already exists
if (Client != null)
{
this.LogDebug("Cleaning up disconnected client");
KillClient(SocketStatus.SOCKET_STATUS_BROKEN_LOCALLY);
}
// This handles both password and keyboard-interactive (like on OS-X, 'nixes)
KeyboardInteractiveAuthenticationMethod kauth = new KeyboardInteractiveAuthenticationMethod(Username);
kauth.AuthenticationPrompt += new EventHandler<AuthenticationPromptEventArgs>(kauth_AuthenticationPrompt);
PasswordAuthenticationMethod pauth = new PasswordAuthenticationMethod(Username, Password);
this.LogDebug("Creating new SshClient");
ConnectionInfo connectionInfo = new ConnectionInfo(Hostname, Port, Username, pauth, kauth);
Client = new SshClient(connectionInfo);
Client.ErrorOccurred += Client_ErrorOccurred;
//Attempt to connect
ClientStatus = SocketStatus.SOCKET_STATUS_WAITING;
try
{
Client.Connect();
TheStream = Client.CreateShellStream("PDTShell", 100, 80, 100, 200, 65534);
if (TheStream.DataAvailable)
{
// empty the buffer if there is data
string str = TheStream.Read();
}
TheStream.DataReceived += Stream_DataReceived;
this.LogInformation("Connected");
ClientStatus = SocketStatus.SOCKET_STATUS_CONNECTED;
DisconnectLogged = false;
}
catch (SshConnectionException e)
{
var ie = e.InnerException; // The details are inside!!
var errorLogLevel = DisconnectLogged == true ? Debug.ErrorLogLevel.None : Debug.ErrorLogLevel.Error;
if (ie is SocketException)
{
this.LogException(ie, "CONNECTION failure: Cannot reach host, ({1})", Key, ie.Message);
}
if (ie is System.Net.Sockets.SocketException socketException)
{
this.LogException(ie, "'{0}' Connection failure: Cannot reach host '{1}' on port {2}, ({3})",
Key, Hostname, Port, ie.GetType());
}
if (ie is SshAuthenticationException)
{
this.LogException(ie, "Authentication failure for username '{0}', ({1})", this,
Username, ie.Message);
}
else
this.LogException(ie, "Error on connect");
DisconnectLogged = true;
KillClient(SocketStatus.SOCKET_STATUS_CONNECT_FAILED);
if (AutoReconnect)
{
this.LogDebug("Checking autoreconnect: {0}, {1}ms", AutoReconnect, AutoReconnectIntervalMs);
ReconnectTimer.Reset(AutoReconnectIntervalMs);
}
}
catch(SshOperationTimeoutException ex)
{
this.LogWarning("Connection attempt timed out: {message}", ex.Message);
DisconnectLogged = true;
KillClient(SocketStatus.SOCKET_STATUS_CONNECT_FAILED);
if (AutoReconnect)
{
this.LogDebug("Checking autoreconnect: {0}, {1}ms", AutoReconnect, AutoReconnectIntervalMs);
ReconnectTimer.Reset(AutoReconnectIntervalMs);
}
}
catch (Exception e)
{
var errorLogLevel = DisconnectLogged == true ? Debug.ErrorLogLevel.None : Debug.ErrorLogLevel.Error;
this.LogException(e, "Unhandled exception on connect");
DisconnectLogged = true;
KillClient(SocketStatus.SOCKET_STATUS_CONNECT_FAILED);
if (AutoReconnect)
{
this.LogDebug("Checking autoreconnect: {0}, {1}ms", AutoReconnect, AutoReconnectIntervalMs);
ReconnectTimer.Reset(AutoReconnectIntervalMs);
}
}
}
}
finally
{
connectLock.Release();
}
}
/// <summary>
/// Disconnect the clients and put away it's resources.
/// </summary>
public void Disconnect()
{
ConnectEnabled = false;
// Stop trying reconnects, if we are
if (ReconnectTimer != null)
{
ReconnectTimer.Stop();
// ReconnectTimer = null;
}
KillClient(SocketStatus.SOCKET_STATUS_BROKEN_LOCALLY);
}
/// <summary>
/// Kills the stream, cleans up the client and sets it to null
/// </summary>
private void KillClient(SocketStatus status)
{
KillStream();
try
{
if (Client != null)
{
Client.ErrorOccurred -= Client_ErrorOccurred;
Client.Disconnect();
Client.Dispose();
Client = null;
ClientStatus = status;
this.LogDebug("Disconnected");
}
}
catch (Exception ex)
{
this.LogException(ex,"Exception in Kill Client");
}
}
/// <summary>
/// Kills the stream
/// </summary>
void KillStream()
{
try
{
if (TheStream != null)
{
TheStream.DataReceived -= Stream_DataReceived;
TheStream.Close();
TheStream.Dispose();
TheStream = null;
this.LogDebug("Disconnected stream");
}
}
catch (Exception ex)
{
this.LogException(ex, "Exception in Kill Stream:{0}");
}
}
/// <summary>
/// Handles the keyboard interactive authentication, should it be required.
/// </summary>
void kauth_AuthenticationPrompt(object sender, AuthenticationPromptEventArgs e)
{
foreach (AuthenticationPrompt prompt in e.Prompts)
if (prompt.Request.IndexOf("Password:", StringComparison.InvariantCultureIgnoreCase) != -1)
prompt.Response = Password;
}
/// <summary>
/// Handler for data receive on ShellStream. Passes data across to queue for line parsing.
/// </summary>
void Stream_DataReceived(object sender, ShellDataEventArgs e)
{
if (((ShellStream)sender).Length <= 0L)
{
return;
}
var response = ((ShellStream)sender).Read();
var bytesHandler = BytesReceived;
if (bytesHandler != null)
{
var bytes = Encoding.UTF8.GetBytes(response);
if (StreamDebugging.RxStreamDebuggingIsEnabled)
{
this.LogInformation("Received {1} bytes: '{0}'", ComTextHelper.GetEscapedText(bytes), bytes.Length);
}
bytesHandler(this, new GenericCommMethodReceiveBytesArgs(bytes));
}
var textHandler = TextReceived;
if (textHandler != null)
{
if (StreamDebugging.RxStreamDebuggingIsEnabled)
this.LogInformation("Received: '{0}'", ComTextHelper.GetDebugText(response));
textHandler(this, new GenericCommMethodReceiveTextArgs(response));
}
}
/// <summary>
/// Error event handler for client events - disconnect, etc. Will forward those events via ConnectionChange
/// event
/// </summary>
void Client_ErrorOccurred(object sender, ExceptionEventArgs e)
{
CrestronInvoke.BeginInvoke(o =>
{
if (e.Exception is SshConnectionException || e.Exception is System.Net.Sockets.SocketException)
this.LogError("Disconnected by remote");
else
this.LogException(e.Exception, "Unhandled SSH client error");
try
{
connectLock.Wait();
KillClient(SocketStatus.SOCKET_STATUS_BROKEN_REMOTELY);
}
finally
{
connectLock.Release();
}
if (AutoReconnect && ConnectEnabled)
{
this.LogDebug("Checking autoreconnect: {0}, {1}ms", AutoReconnect, AutoReconnectIntervalMs);
ReconnectTimer.Reset(AutoReconnectIntervalMs);
}
});
}
/// <summary>
/// Helper for ConnectionChange event
/// </summary>
void OnConnectionChange()
{
if (ConnectionChange != null)
ConnectionChange(this, new GenericSocketStatusChageEventArgs(this));
}
#region IBasicCommunication Members
/// <summary>
/// Sends text to the server
/// </summary>
/// <param name="text"></param>
public void SendText(string text)
{
try
{
if (Client != null && TheStream != null && IsConnected)
{
if (StreamDebugging.TxStreamDebuggingIsEnabled)
this.LogInformation(
"Sending {length} characters of text: '{text}'",
text.Length,
ComTextHelper.GetDebugText(text));
TheStream.Write(text);
TheStream.Flush();
}
else
{
this.LogDebug("Client is null or disconnected. Cannot Send Text");
}
}
catch (ObjectDisposedException ex)
{
this.LogException(ex, "ObjectDisposedException sending {message}", text);
KillClient(SocketStatus.SOCKET_STATUS_CONNECT_FAILED);
ReconnectTimer.Reset();
}
catch (Exception ex)
{
this.LogException(ex, "Exception sending text: {message}", text);
}
}
/// <summary>
/// Sends Bytes to the server
/// </summary>
/// <param name="bytes"></param>
public void SendBytes(byte[] bytes)
{
try
{
if (Client != null && TheStream != null && IsConnected)
{
if (StreamDebugging.TxStreamDebuggingIsEnabled)
this.LogInformation("Sending {0} bytes: '{1}'", bytes.Length, ComTextHelper.GetEscapedText(bytes));
TheStream.Write(bytes, 0, bytes.Length);
TheStream.Flush();
}
else
{
this.LogDebug("Client is null or disconnected. Cannot Send Bytes");
}
}
catch (ObjectDisposedException ex)
{
this.LogException(ex, "ObjectDisposedException sending {message}", ComTextHelper.GetEscapedText(bytes));
KillClient(SocketStatus.SOCKET_STATUS_CONNECT_FAILED);
ReconnectTimer.Reset();
}
catch (Exception ex)
{
this.LogException(ex, "Exception sending {message}", ComTextHelper.GetEscapedText(bytes));
}
}
#endregion
}
//*****************************************************************************************************
//*****************************************************************************************************
/// <summary>
/// Fired when connection changes
/// </summary>
public class SshConnectionChangeEventArgs : EventArgs
{
/// <summary>
/// Connection State
/// </summary>
public bool IsConnected { get; private set; }
/// <summary>
/// Connection Status represented as a ushort
/// </summary>
public ushort UIsConnected { get { return (ushort)(Client.IsConnected ? 1 : 0); } }
/// <summary>
/// The client
/// </summary>
public GenericSshClient Client { get; private set; }
/// <summary>
/// Socket Status as represented by
/// </summary>
public ushort Status { get { return Client.UStatus; } }
/// <summary>
/// S+ Constructor
/// </summary>
public SshConnectionChangeEventArgs() { }
/// <summary>
/// EventArgs class
/// </summary>
/// <param name="isConnected">Connection State</param>
/// <param name="client">The Client</param>
public SshConnectionChangeEventArgs(bool isConnected, GenericSshClient client)
{
IsConnected = isConnected;
Client = client;
}
}
}