Dart

IMAP over Multiple Hop SSH

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

Application => ServerSSH1 => ServerSSH2 => IMAPServer

The ConnectThroughSsh and UseSsh methods are added in Chilkat version 9.5.0.55 to accomplish this task.

Dart

import 'package:chilkat/chilkat.dart';

void main() {
  // This example assumes the Chilkat API to have been previously unlocked.
  // See Global Unlock Sample for sample code.

  final ssh1 = CkSsh();

  // Connect directly to the 1st SSH server.
  try {
    ssh1.connect('serverssh1.com', 22);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // Authenticate using login/password:
  try {
    ssh1.authenticatePw('ssh1Login', 'ssh1Password');
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // 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.
  final ssh2 = CkSsh();
  try {
    ssh2.connectThroughSsh(ssh1, 'serverssh2.com', 22);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // Authenticate with ssh2...
  try {
    ssh2.authenticatePw('ssh2Login', 'ssh2Password');
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  final imap = CkImap();

  // Tell the IMAP object to connect to the IMAP server though the ssh2 tunnel (which itself is routed through ssh1).
  // The connection looks like this:  Application => ServerSSH1 => ServerSSH2 => IMAPServer
  try {
    imap.useSsh(ssh2);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  imap.ssl = true;
  imap.port = 993;

  // Connect to an IMAP server (through the multi-hop SSH tunnel)
  try {
    imap.connect('imap.someimapserver.com');
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // Login
  try {
    imap.login('myLogin', 'myPassword');
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // Do whatever needs to be done...  for example,

  // Create the new email folder (sub-mailbox) on the IMAP server.
  // If no folder path is provided, the new folder is a sub-mailbox of Inbox.
  try {
    imap.createMailbox('newFolder');
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  print('Success.');

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

  // 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();
}