(PHP Extension) Send Signed Email using PFX File

Demonstrates how to send a signed email using a digital certificate w/ private key stored in a PFX file.

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<?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 sending and receiving email.
$mailman = new CkMailMan();

// Set the SMTP server.
$mailman->put_SmtpHost('smtp.mymailserver.com');

// Create a new email object
$email = new CkEmail();

$email->put_Subject('This email is signed');
$email->put_Body('This is a digitally signed mail');
$email->put_From('Chilkat Admin <admin@chilkatsoft.com>');
$success = $email->AddTo('Chilkat Support','support@chilkatsoft.com');

// Indicate that the email should be sent signed.
$email->put_SendSigned(true);

// Tell the mailman to use a PFX file as a source for locating
// the certificate and private key required for signing.
// The certificate chosen for signing will be the one that
// matches the sender's email address, which also has
// a private key.  All intermediate certs in the chain of 
// authentication, up to and including the root, will
// be included in the signature.
$success = $mailman->AddPfxSourceFile('/pfx_files/chilkatsoft_secret.pfx','secret');
if ($success != true) {
    print $mailman->lastErrorText() . "\n";
    exit;
}

// Signed email can be sent in two different ways.  
// In a multipart/signed email, the signature is attached as a separate MIME part.
// In an opaque email (signedData) the content of the email is encapsulated within the signature
// and the email is sent as "application/pkcs7-mime". 
// Either should be fine, but some receiving systems might require one or the other..
$mailman->put_OpaqueSigning(false);

// Send a signed email.
$success = $mailman->SendEmail($email);
if ($success != true) {
    print $mailman->lastErrorText() . "\n";
}
else {
    // The LastErrorText property provides information
    // even when successful.
    print $mailman->lastErrorText() . "\n";
    print 'Mail Sent!' . "\n";
}


?>