(PHP Extension) POP3 Verify Signed (S/MIME) Email

Demonstrates how to download and verify digitally signed S/MIME email.

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

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

<?php

include("chilkat.php");

$success = false;

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

$mailman = new CkMailMan();

// Set the POP3 server's hostname
$mailman->put_MailHost('pop.example.com');

// Set the POP3 login/password.
$mailman->put_PopUsername('myLogin');
$mailman->put_PopPassword('myPassword');

$stUidls = new CkStringTable();
$success = $mailman->FetchUidls($stUidls);
if ($success == false) {
    print $mailman->lastErrorText() . "\n";
    exit;
}

$email = new CkEmail();
$cert = new CkCert();

$count = $stUidls->get_Count();
$i = 0;
while ($i < $count) {
    // Download the full email.
    $success = $mailman->FetchByUidl($stUidls->stringAt($i),false,0,$email);
    if ($success == false) {
        print $mailman->lastErrorText() . "\n";
        exit;
    }

    print $i . "\n";
    print 'From: ' . $email->from() . "\n";
    print 'Subject: ' . $email->subject() . "\n";

    // The security layers of signed and/or encrypted emails
    // are automatically "unwrapped" when loaded into
    // a Chilkat email object.
    // An application only needs to check to see if an email
    // was received signed or encrypted, and then examine
    // the success/failure.  For example:
    if ($email->get_ReceivedSigned() == true) {

        print 'This email was signed.' . "\n";

        // Check to see if the signatures were verified.
        if ($email->get_SignaturesValid() == true) {
            print 'Digital signature(s) verified.' . "\n";
            print 'Signer: ' . $email->signedBy() . "\n";

            $success = $email->LastSignerCert(0,$cert);
            if ($success == false) {
                print $email->lastErrorText() . "\n";
                exit;
            }

            print 'Signing cert: ' . $cert->subjectCN() . "\n";
        }

    }
    else {
        print 'Digital signature verification failed.' . "\n";
    }

    $i = $i + 1;
}

$mailman->Pop3EndSession();

?>