(Delphi ActiveX) SSH Tunnel (Port Forwarding via direct-tcpip channel)

Demonstrates how to create an SSH tunnel to a remote hostname:port via a direct-tcpip channel.

Chilkat for Delphi Downloads Chilkat ActiveX DLL for Delphi Chilkat non-ActiveX DLL for Delphi * The examples here use the ActiveX DLL.

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Chilkat_TLB;

...

procedure TForm1.Button1Click(Sender: TObject);
var
ssh: TChilkatSsh;
hostname: WideString;
port: Integer;
success: Integer;
channelNum: Integer;
httpReq: WideString;
caseSensitive: Integer;
matchStr: WideString;
responseHeader: WideString;
numBytesRead: Integer;
pollTimeoutMs: Integer;
htmlBody: WideString;

begin
// This example assumes the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

ssh := TChilkatSsh.Create(Self);

// Connect to an SSH server:

// Hostname may be an IP address or hostname:
hostname := '192.168.1.117';
port := 22;

success := ssh.Connect(hostname,port);
if (success <> 1) then
  begin
    Memo1.Lines.Add(ssh.LastErrorText);
    Exit;
  end;

// Wait a max of 5 seconds when reading responses..
ssh.IdleTimeoutMs := 5000;

// Authenticate using login/password:
success := ssh.AuthenticatePw('chilkat','myPassword');
if (success <> 1) then
  begin
    Memo1.Lines.Add(ssh.LastErrorText);
    Exit;
  end;

// Open a direct-tcpip channel.  We want the SSH server to connect
// to www.chilkatsoft.com, port 80 (i.e. the web server).
// Data sent through the SSH tunnel is forwarded to the remote
// host:port.  (Note: The remote host:port does not need to be 
// a web server.  It can be anything.  It can be your own
// customer application server that listens on a port, or any
// other type of server.)
// When we read from the SSH channel, we'll be reading data
// sent from the remote host:port (i.e. the web server in this
// example).

channelNum := ssh.OpenDirectTcpIpChannel('www.chilkatsoft.com',80);
if (channelNum < 0) then
  begin
    Memo1.Lines.Add(ssh.LastErrorText);
    Exit;
  end;

// Build a simple HTTP GET request for http://www.chilkatsoft.com/xyz.html
httpReq := 'GET /xyz123.html HTTP/1.1' + #13#10 + 'Host: www.chilkatsoft.com' + #13#10 + #13#10;

// Send the HTTP request:
success := ssh.ChannelSendString(channelNum,httpReq,'ansi');
if (success <> 1) then
  begin
    Memo1.Lines.Add(ssh.LastErrorText);
    Exit;
  end;

// Get the HTTP response.
// First read the HTTP response header which ends with a double CRLF.
// Calling ChannelReceiveUntilMatch will receive until match string is seen,
// or until a timeout occurs (IdleTimeoutMs property).  ChannelReceiveUntilMatch
// may read beyond the match string, but it will stop reading as soon as the match
// string is seen.
caseSensitive := 0;
matchStr := #13#10 + #13#10;
success := ssh.ChannelReceiveUntilMatch(channelNum,matchStr,'ansi',caseSensitive);
if (success <> 1) then
  begin
    Memo1.Lines.Add(ssh.LastErrorText);
    Exit;
  end;

// Extract the HTTP header from the receive buffer.
// (GetReceiveTextS extracts up to and including the match string from the receive buffer)

responseHeader := ssh.GetReceivedTextS(channelNum,matchStr,'ansi');
Memo1.Lines.Add('---- HTTP Response Header ----');
Memo1.Lines.Add(responseHeader);

// Now get the body of the HTTP response (this is the HTML content
// of http://www.chilkatsoft.com/xyz.html
// It's possible we've already received the entire HTTP response in the
// call to ChannelReceiveUntilMatch.  Therefore, we'll poll for any remaining data
// and wait a max of .2 seconds.

pollTimeoutMs := 200;
numBytesRead := ssh.ChannelPoll(channelNum,pollTimeoutMs);
// We're not checking for an error here.
// A return value of -2 means that no data was available and the poll simply timed out (not an error)
// A return value of -1 indicates an error.
// A return value greater than 0 indicates that additional data was received.

Memo1.Lines.Add('---- HTML BODY ----');

// Extract the remainder of the accumulated data in the internal receive buffer.
// This should be our HTML body:

htmlBody := ssh.GetReceivedText(channelNum,'ansi');
Memo1.Lines.Add(htmlBody);

// Close the channel:
success := ssh.ChannelSendClose(channelNum);
if (success <> 1) then
  begin
    Memo1.Lines.Add(ssh.LastErrorText);
    Exit;
  end;

// Disconnect
ssh.Disconnect();
end;