SSH Tunnel using an HTTP proxy

Demonstrates how to establish an SSH tunnel that uses an HTTP proxy.

uses
    Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
    Dialogs, StdCtrls,
    OleCtrls;

...

procedure TForm1.Button1Click(Sender: TObject);
var
sshTunnel: ERROR-1;
success: Integer;
listenPort: Integer;
maxWaitMs: Integer;

begin
sshTunnel := TChilkatSshTunnel.Create(Self);

success := sshTunnel.UnlockComponent('30-day trial');
if (success <> 1) then
  begin
    ShowMessage(sshTunnel.LastErrorText);
    Exit;
  end;

//  The DestHostname / DestPort is the server with which we
//  are ultimately communicating.
sshTunnel.DestPort := 1433;
sshTunnel.DestHostname := 'myServer.com';

//  Provide information about the location of the SSH server,
//  and the authentication to be used with it. This is the
//  login information for the SSH server.
sshTunnel.SshHostname := '192.168.1.108';
sshTunnel.SshPort := 22;
sshTunnel.SshLogin := 'mySshLogin';
sshTunnel.SshPassword := 'mySshPassword';

//  To connect through an HTTP proxy, set the HttpProxyHostname
//  and HttpProxyPort properties to the hostname (or IP address)
//  and port of the HTTP proxy.  Typical port numbers used by
//  HTTP proxy servers are 3128 and 8080.
sshTunnel.HttpProxyHostname := 'www.my-http-proxy.com';
sshTunnel.HttpProxyPort := 3128;

//  Important:  Your HTTP proxy server must allow non-HTTP
//  traffic to pass.  Otherwise this does not work.

//  Start accepting connections in a background thread.
//  The SSH tunnels are autonomously run in a background
//  thread.  There is one background thread for accepting
//  connections, and another for managing the tunnel pool.
listenPort := 3316;
success := sshTunnel.BeginAccepting(listenPort);
if (success <> 1) then
  begin
    ShowMessage(sshTunnel.LastErrorText);
    Exit;
  end;

//  At this point you may write code to communicate with
//  the server at DestHostname/DestPort.  This could be anything --
//  it could be WinSock, ADO/ODBC code, Chilkat Socket, etc.
//  However, instead of connecting directly to DestHostname/DestPort,
//  your code would connect to localhost:3316 (because this
//  is the listenPort of the SSH Tunnel

//  This is what happens when you connect to localhost:3316
//  1) The connection is accepted by the SSH tunnel
//      background thread (which was started in the call to BeginAccepting).
//  2) In the background thread, a connection to a remote SSH
//      server is established via an HTTP proxy.
//  3) Port-forwarding is setup so that the remote SSH server connects
//     to the DestHostname/DestPort.
//  4) Data sent by your application to localhost:3316 is ultimately forwarded to DestHostname/DestPort
//   5) Data sent back from DestHostname/DestPort is forwarded back and received by your application

//  When you're finished with the  connection, you may
//  stop the background tunnel threads:
//  Stop the background thread that accepts new connections:
success := sshTunnel.StopAccepting();
if (success <> 1) then
  begin
    ShowMessage(sshTunnel.LastErrorText);
    Exit;
  end;
//  If any background tunnels are still in existence (and managed
//  by a single SSH tunnel pool background thread), stop them...
maxWaitMs := 1000;
success := sshTunnel.StopAllTunnels(maxWaitMs);
if (success <> 1) then
  begin
    ShowMessage(sshTunnel.LastErrorText);
    Exit;
  end;
end;