(Delphi ActiveX) POP3 over Multiple Hop SSH

Demonstrates how to read POP3 email (using TCP or TLS) tunneled through mulitple-hop SSH. The scheme looks like this:

Application => ServerSSH1 => ServerSSH2 => POP3Server

Note: This example requires Chilkat v11.0.0 or greater.

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
success: Integer;
ssh1: TChilkatSsh;
ssh2: TChilkatSsh;
mailman: TChilkatMailMan;
numMessages: Integer;
email: TChilkatEmail;
i: Integer;

begin
success := 0;

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

ssh1 := TChilkatSsh.Create(Self);

// Connect directly to the 1st SSH server.
success := ssh1.Connect('serverssh1.com',22);
if (success = 0) then
  begin
    Memo1.Lines.Add(ssh1.LastErrorText);
    Exit;
  end;

// Authenticate using login/password:
success := ssh1.AuthenticatePw('ssh1Login','ssh1Password');
if (success = 0) then
  begin
    Memo1.Lines.Add(ssh1.LastErrorText);
    Exit;
  end;

// Connect through the 1st SSH connection to reach a 2nd SSH server.
// Note: Any number of SSH connections may be simultaneously tunneled through a single
// existing SSH connection.
ssh2 := TChilkatSsh.Create(Self);
success := ssh2.ConnectThroughSsh(ssh1.ControlInterface,'serverssh2.com',22);
if (success = 0) then
  begin
    Memo1.Lines.Add(ssh2.LastErrorText);
    Exit;
  end;

// Authenticate with ssh2...
success := ssh2.AuthenticatePw('ssh2Login','ssh2Password');
if (success = 0) then
  begin
    Memo1.Lines.Add(ssh2.LastErrorText);
    Exit;
  end;

mailman := TChilkatMailMan.Create(Self);

// Tell the mailman object to connect to the POP3 server though the ssh2 tunnel (which itself is routed through ssh1).
// The connection looks like this:  Application => ServerSSH1 => ServerSSH2 => POP3Server
success := mailman.UseSsh(ssh2.ControlInterface);
if (success = 0) then
  begin
    Memo1.Lines.Add(mailman.LastErrorText);
    Exit;
  end;

// Set the POP3 server's hostname
mailman.MailHost := 'pop.example.com';

// Set the POP3 login/password.
mailman.PopUsername := 'myLogin';
mailman.PopPassword := 'myPassword';

// Establish the POP3 connection through the ssh2 tunnel.
success := mailman.Pop3BeginSession();
if (success = 0) then
  begin
    Memo1.Lines.Add(mailman.LastErrorText);
    Exit;
  end;

// Get the number of messages in the mailbox.
numMessages := mailman.GetMailboxCount();

email := TChilkatEmail.Create(Self);
i := 1;
while i <= numMessages do
  begin
    // Fetch by the message number (not by the UIDL)
    success := mailman.FetchOne(0,0,i,email.ControlInterface);
    if (success = 0) then
      begin
        Memo1.Lines.Add(mailman.LastErrorText);
        Exit;
      end;

    Memo1.Lines.Add(email.From + ': ' + email.Subject + #10);

    i := i + 1;
  end;

// Close the connection with the POP3 server.  (This closes the tunnel through ssh2)
// The connection with ssh2 is still alive, and may be used for more connections.
success := mailman.Pop3EndSession();

// Close the connection with ssh2.  (This closes the the tunnel through ssh1.)
// The connection with ssh1 is still alive, and may be used for more connections.

ssh2.Disconnect();

ssh1.Disconnect();
end;