Creating an interactive SSH session

To create an interactive SSH session you must first understand how to establish a connection, send data to the SSH server and receive data from the SSH server. Each of these is covered in the sections titled Establishing a connection , Receiving data and Sending data respectively.

Example

[C#]

using System;

using System.IO;

using Jscape.Ssh;

namespace SshExample

{

 /// <summary>

 /// Demonstrates creating an interactive SSH client.

 /// </summary>

 ///

 class SshExample

 {

         private const string NEWLINE = "\n";

         private bool connected = false;

         public SshExample() {

                 // get hostname and login information

                 Console.Write("Enter hostname: ");

                 string hostname = Console.ReadLine();

                 Console.Write("Enter username: ");

                 string username = Console.ReadLine();

                 Console.Write("Enter password: ");

                 string password = Console.ReadLine();

                 // create login credentials

                 SshParameters sshParams = new SshParameters(hostname,username,password);

                 // create new Ssh instance

                 Ssh ssh = new Ssh(sshParams);

                 // register event handlers

                 ssh.SshDataEvent += new Ssh.SshDataEventHandler(OnData);

                 ssh.SshConnectedEvent += new Ssh.SshConnectedEventHandler(OnConnected);

                 ssh.SshDisconnectedEvent += new Ssh.SshDisconnectedEventHandler(OnDisconnected);

                 // establish connection

                 ssh.Connect();

                 // get output stream

                 Stream output = ssh.GetStream();

                 // read data from console and write to server

                 string line = null;

                 while((line = Console.ReadLine()) != null && connected) {        

                         byte[] data = System.Text.Encoding.UTF8.GetBytes(line);

                         byte[] nl = System.Text.Encoding.UTF8.GetBytes(NEWLINE);

                         output.Write(data,0,data.Length);

                         output.Write(nl,0,nl.Length);

                         try {

                                 output.Flush();

                         } catch(Exception e) {

                                 break;

                         }

                 }

                 // disconnect

                 ssh.Disconnect();

         }

         /// <summary>

         /// Invoked when data is recevied from SSH server

         /// </summary>

         /// <param name="sender">the source of this event</param>

         /// <param name="e">the event</param>

         public void OnData(object sender, SshDataEventArgs e) {

                 Console.Write(e.Data);

         }

         /// <summary>

         /// Invoked when a connection is established with SSH server

         /// </summary>

         /// <param name="sender">the source of this event</param>

         /// <param name="e">the event</param>

         public void OnConnected(object sender, SshConnectedEventArgs e) {

                 connected = true;

                 Console.WriteLine("Connected to host " + e.Hostname);

         }

         /// <summary>

         /// Invoked when connection is released from SSH server.

         /// </summary>

         /// <param name="sender"></param>

         /// <param name="e"></param>

         public void OnDisconnected(object sender, SshDisconnectedEventArgs e) {

                 connected = false;

                 Console.WriteLine("Disconnected from host " + e.Hostname);

                 Console.WriteLine("");

                 Console.WriteLine("Press ENTER to exit.");

         }

         /// <summary>

         /// The main entry point for the application.

         /// </summary>

         [STAThread]

         static void Main(string[] args)

         {

                 SshExample example = new SshExample();

         }

 }

}

[VB]

Imports System

Imports System.IO

Imports Jscape.Ssh

Namespace SshExample

 Class SshExample

         Private Const NEWLINE As String = "" & Microsoft.VisualBasic.Chr(10) & ""

         Private connected As Boolean = False

         Public Sub New()

                 ' get hostname and login information

                 Console.Write("Enter hostname: ")

                 Dim hostname As String = Console.ReadLine

                 Console.Write("Enter username: ")

                 Dim username As String = Console.ReadLine

                 Console.Write("Enter password: ")

                 Dim password As String = Console.ReadLine

                 ' create login credentials

                 Dim sshParams As SshParameters = New SshParameters(hostname, username, password)

                 Dim ssh As Ssh = New Ssh(sshParams)

                 ' register event handlers

                 AddHandler ssh.SshDataEvent, AddressOf OnData

                 AddHandler ssh.SshConnectedEvent, AddressOf OnConnected

                 AddHandler ssh.SshDisconnectedEvent, AddressOf OnDisconnected

                 ' connect to server

                 ssh.Connect()

                 ' get output stream from server

                 Dim Output As Stream = ssh.GetStream

                 ' read data from local console and send to server

                 Dim Line As String = Console.ReadLine

                 While Not (Line Is Nothing) AndAlso connected

                         Dim data As Byte() = System.Text.Encoding.UTF8.GetBytes(Line)

                         Dim nl As Byte() = System.Text.Encoding.UTF8.GetBytes(NEWLINE)

                         output.Write(data, 0, data.Length)

                         output.Write(nl, 0, nl.Length)

                         Try

                                 output.Flush()

                         Catch e As Exception

                                 ' break

                         End Try

                         Line = Console.ReadLine

                 End While

                 ' disconnect

                 ssh.Disconnect()

         End Sub

         Public Sub OnData(ByVal sender As Object, ByVal e As SshDataEventArgs)

                 Console.Write(e.Data)

         End Sub

         Public Sub OnConnected(ByVal sender As Object, ByVal e As SshConnectedEventArgs)

                 connected = True

                 Console.WriteLine("Connected to host " + e.Hostname)

         End Sub

         Public Sub OnDisconnected(ByVal sender As Object, ByVal e As SshDisconnectedEventArgs)

                 connected = False

                 Console.WriteLine("Disconnected from host " + e.Hostname)

                 Console.WriteLine("")

                 Console.WriteLine("Press ENTER to exit.")

         End Sub

         <STAThread()> _

         Shared Sub Main(ByVal args As String())

                 Dim example As SshExample = New SshExample

         End Sub

 End Class

End Namespace