(PHP Extension) POP3 SSH Tunneling (Port Forwarding)

Demonstrates how to connect to a POP3 server through an SSH tunnel. Reads a POP3 mailbox and display the FROM and SUBJECT header fields of each email.

Chilkat PHP Downloads PHP Extension for Windows, Linux, MacOS, Alpine Linux, Solaris

<?php

// The version number (9_5_0) should match version of the Chilkat extension used, omitting the micro-version number.
// For example, if using Chilkat v9.5.0.48, then include as shown here:
include("chilkat_9_5_0.php");

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

// The mailman object is used for receiving (POP3) 
// and sending (SMTP) email.
$mailman = new CkMailMan();

// The SSH hostname may be a hostname or an 
// IP address, such as "192.168.1.108".
// The port is typically 22 (the standard port for SSH).
$sshHostname = 'www.my-ssh-server.com';
$sshPort = 22;

// Connect to an SSH server and establish the SSH tunnel:
$success = $mailman->SshOpenTunnel($sshHostname,$sshPort);
if ($success != true) {
    print $mailman->lastErrorText() . "\n";
    exit;
}

// Authenticate with the SSH server via a login/password
// or with a public key.
// This example demonstrates SSH password authentication.
// Note: This is not authenticating with the POP3 server, it is
// for authenticating with the SSH server, which is separate.
$success = $mailman->SshAuthenticatePw('ssh_login','ssh_password');
if ($success != true) {
    print $mailman->lastErrorText() . "\n";
    exit;
}

// OK, the SSH tunnel is setup.  The mailman may
// be used exactly the same as usual, except all communications
// are now sent through the SSH tunnel.

// The SSH tunnel may be kept open for any number of 
// POP3 connections.  

// Set the POP3 server's hostname
$mailman->put_MailHost('mail.my-pop3-server.com');

// Set the POP3 settings for your POP3 server:
$mailman->put_PopUsername('pop3_login');
$mailman->put_PopPassword('pop3_password');
$mailman->put_MailPort(995);
$mailman->put_PopSsl(true);

// Connect to the POP3 server through the already-established SSH tunnel:
$success = $mailman->Pop3BeginSession();
if ($success != true) {
    print $mailman->lastErrorText() . "\n";
    exit;
}

// A visual inspection of the LastErrorText after
// a successful POP3 connection will confirm the SSH tunneling.
// Note: If the POP3 connection uses SSL/TLS, then the SSL/TLS 
// secure channel will be wrapped within the SSH tunnel.
print $mailman->lastErrorText() . "\n";

// How many messages are in the POP3 inbox?
$numToDownload = $mailman->GetMailboxCount();
if ($numToDownload > 5) {
    $numToDownload = 5;
}

if ($numToDownload == 0) {
    exit;
}

// Download a max of 5 messages

for ($i = 1; $i <= $numToDownload; $i++) {
    // email is a CkEmail
    $email = $mailman->FetchByMsgnum($i);
    if ($mailman->get_LastMethodSuccess() == false) {
        print $mailman->lastErrorText() . "\n";
        exit;
    }

    print $email->from() . "\n";
    print $email->subject() . "\n";
    print '----' . "\n";

}

// Close the connection with the POP3 server, leaving the SSH tunnel open for subsequent POP3 connections.
$success = $mailman->Pop3EndSession();
if ($success != true) {
    print $mailman->lastErrorText() . "\n";
    exit;
}

// Try connecting to a different POP3 server through the same aleady setup SSH tunnel:
// Set the POP3 server's hostname
$mailman->put_MailHost('mail.my-pop3-server2.com');

// Set the POP3 settings for your POP3 server:
$mailman->put_PopUsername('pop3_login2');
$mailman->put_PopPassword('pop3_password2');
$mailman->put_MailPort(110);
$mailman->put_PopSsl(false);

$success = $mailman->Pop3BeginSession();
if ($success != true) {
    print $mailman->lastErrorText() . "\n";
    exit;
}

// Review the LastErrorText to see that the connection was made via the SSH tunnel:
print $mailman->lastErrorText() . "\n";

$success = $mailman->Pop3EndSession();
if ($success != true) {
    print $mailman->lastErrorText() . "\n";
    exit;
}

// Close the SSH tunnel.
$success = $mailman->SshCloseTunnel();
if ($success != true) {
    print $mailman->lastErrorText() . "\n";
    exit;
}


?>