(PHP ActiveX) Add S/MIME Signature using PFX

Add a digital signature to a MIME message using the certificate + private key from a PFX file.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

<?php

$mime = new COM("Chilkat_9_5_0.Mime");

$success = $mime->UnlockComponent('Anything for 30-day trial');
if ($success == 0) {
    print $mime->LastErrorText . "\n";
    exit;
}

//  Load a PFX file into a certificate object.
$cert = new COM("Chilkat_9_5_0.Cert");
$pfxFilepath = 'pfxFiles/something.pfx';
$pfxPassword = 'secret';
$success = $cert->LoadPfxFile($pfxFilepath,$pfxPassword);
if ($success == 0) {
    print $cert->LastErrorText . "\n";
    exit;
}

$success = $mime->SetBodyFromPlainText('This is the plain-text MIME body.');

$mime->Charset = 'utf-8';
$mime->Encoding = 'quoted-printable';

//  Sign the MIME (adds a PKCS7 detached signature)
$success = $mime->AddDetachedSignature($cert);
if ($success == 0) {
    print $mime->LastErrorText . "\n";
    exit;
}

//  Save the S/MIME to a file.
$success = $mime->SaveMime('/temp/signedMime.txt');
if ($success == 0) {
    print $mime->LastErrorText . "\n";
    exit;
}

print 'success!' . "\n";

?>