(Delphi DLL) SSH Tunnel with Dynamic Port Forwarding

Demonstrates how to start a background thread that runs a portable SSH tunnel w/ dynamic port forwarding that the foreground thread can use for establishing connections through an SSH tunnel.

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

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

...

procedure TForm1.Button1Click(Sender: TObject);
var
chilkatGlob: HCkGlobal;
success: Boolean;
tunnel: HCkSshTunnel;
sshHostname: PWideChar;
sshPort: Integer;
url: PWideChar;
http: HCkHttp;
html: PWideChar;
waitForThreadExit: Boolean;

begin
// Starting in v9.5.0.49, all Chilkat classes can be unlocked at once at the beginning of a program
// by calling UnlockBundle.  It requires a Bundle unlock code.
chilkatGlob := CkGlobal_Create();
success := CkGlobal_UnlockBundle(chilkatGlob,'Anything for 30-day trial.');
if (success <> True) then
  begin
    Memo1.Lines.Add(CkGlobal__lastErrorText(chilkatGlob));
    Exit;
  end;

// This example requires Chilkat version 9.5.0.50 or greater.
tunnel := CkSshTunnel_Create();

sshHostname := 'sftp.example.com';
sshPort := 22;

// Connect to an SSH server and establish the SSH tunnel:
success := CkSshTunnel_Connect(tunnel,sshHostname,sshPort);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkSshTunnel__lastErrorText(tunnel));
    Exit;
  end;

// Authenticate with the SSH server via a login/password
// or with a public key.  
// This example demonstrates SSH password authentication.
success := CkSshTunnel_AuthenticatePw(tunnel,'mySshLogin','mySshPassword');
if (success <> True) then
  begin
    Memo1.Lines.Add(CkSshTunnel__lastErrorText(tunnel));
    Exit;
  end;

// Indicate that the background SSH tunnel thread will behave as a SOCKS proxy server
// with dynamic port forwarding:
CkSshTunnel_putDynamicPortForwarding(tunnel,True);

// We may optionally require that connecting clients authenticate with our SOCKS proxy server.
// To do this, set an inbound username/password.  Any connecting clients would be required to 
// use SOCKS5 with the correct username/password.
// If no inbound username/password is set, then our SOCKS proxy server will accept both
// SOCKS4 and SOCKS5 unauthenticated connections.

CkSshTunnel_putInboundSocksUsername(tunnel,'chilkat123');
CkSshTunnel_putInboundSocksPassword(tunnel,'password123');

// Start the listen/accept thread to begin accepting SOCKS proxy client connections.
// Listen on port 1080.
success := CkSshTunnel_BeginAccepting(tunnel,1080);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkSshTunnel__lastErrorText(tunnel));
    Exit;
  end;

// Now that a background thread is running a SOCKS proxy server that forwards connections
// through an SSH tunnel, it is possible to use any Chilkat implemented protocol that is SOCKS capable,
// such as HTTP, POP3, SMTP, IMAP, FTP, etc.  The protocol may use SSL/TLS because the SSL/TLS
// will be passed through the SSH tunnel to the end-destination.  Also, any number of simultaneous
// connections may be routed through the SSH tunnel.

// For this example, let's do a simple HTTPS request:
url := 'https://www.ethereum.org/';

http := CkHttp_Create();

// Indicate that the HTTP object is to use our portable SOCKS proxy/SSH tunnel running in our background thread.
CkHttp_putSocksHostname(http,'localhost');
CkHttp_putSocksPort(http,1080);
CkHttp_putSocksVersion(http,5);
CkHttp_putSocksUsername(http,'chilkat123');
CkHttp_putSocksPassword(http,'password123');

CkHttp_putSendCookies(http,True);
CkHttp_putSaveCookies(http,True);
CkHttp_putCookieDir(http,'memory');

// Do the HTTPS page fetch (through the SSH tunnel)
html := CkHttp__quickGetStr(http,url);
if (CkHttp_getLastMethodSuccess(http) <> True) then
  begin
    Memo1.Lines.Add(CkHttp__lastErrorText(http));
    Exit;
  end;

// Stop the background listen/accept thread:
waitForThreadExit := True;
success := CkSshTunnel_StopAccepting(tunnel,waitForThreadExit);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkSshTunnel__lastErrorText(tunnel));
    Exit;
  end;

// Close the SSH tunnel (would also kick any remaining connected clients).
success := CkSshTunnel_CloseTunnel(tunnel,waitForThreadExit);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkSshTunnel__lastErrorText(tunnel));
    Exit;
  end;

CkGlobal_Dispose(chilkatGlob);
CkSshTunnel_Dispose(tunnel);
CkHttp_Dispose(http);

end;