Java

Use an Existing Socket SSH Tunnel

Demonstrates the Chilkat MailMan.UseSshTunnel method, which configures MailMan to use an existing SSH tunnel provided by a Socket object for its SMTP and POP3 connections. This example opens and authenticates a tunnel on a Socket, hands it to MailMan, and then verifies an SMTP login through it.

Background: Sharing one already-established SSH tunnel across objects avoids opening (and authenticating) a separate SSH connection for every component that needs to reach the remote network. Here the tunnel lives on a Socket object, which MailMan then routes its SMTP/POP3 traffic through. It is the Socket-based sibling of UseSsh, which shares an Ssh object instead.

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Java

import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    boolean success = false;

    //  Demonstrates the MailMan.UseSshTunnel method, which configures MailMan to use an existing
    //  SSH tunnel provided by a Socket object for its SMTP and POP3 connections.

    //  Open and authenticate the SSH tunnel using a Socket object.
    CkSocket sshTunnel = new CkSocket();
    success = sshTunnel.SshOpenTunnel("ssh.example.com",22);
    if (success == false) {
        System.out.println(sshTunnel.lastErrorText());
        return;
        }

    success = sshTunnel.SshAuthenticatePw("sshUser","sshPassword");
    if (success == false) {
        System.out.println(sshTunnel.lastErrorText());
        return;
        }

    CkMailMan mailman = new CkMailMan();

    //  Configure the SMTP server connection.  These connections will travel through the tunnel.
    mailman.put_SmtpHost("smtp.example.com");
    mailman.put_SmtpPort(465);
    mailman.put_SmtpSsl(true);
    mailman.put_SmtpUsername("user@example.com");
    mailman.put_SmtpPassword("myPassword");

    //  Tell MailMan to route its connections through the existing tunnel.
    success = mailman.UseSshTunnel(sshTunnel);
    if (success == false) {
        System.out.println(mailman.lastErrorText());
        return;
        }

    //  SMTP operations now travel through the shared SSH tunnel.
    success = mailman.VerifySmtpLogin();
    if (success == false) {
        System.out.println(mailman.lastErrorText());
        return;
        }

    System.out.println("Authenticated with the SMTP server through the SSH tunnel.");
  }
}