(PHP Extension) Sign a File to Create a .p7s (Detached Signature)

PHP Extension example to create a detached signature file (.p7s) for any type file. The signature can be verified by calling VerifyP7S and passing the original filename and the .p7s filename.

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.

$crypt = new CkCrypt2();

// Use a digital certificate and private key from a PFX file (.pfx or .p12).
$signingCertSubject = 'Acme Inc';
$pfxFilename = '/Users/chilkat/testData/pfx/acme.pfx';
$pfxPassword = 'test123';

$certStore = new CkCertStore();
$success = $certStore->LoadPfxFile($pfxFilename,$pfxPassword);
if ($success != true) {
    print $certStore->lastErrorText() . "\n";
    exit;
}

// cert is a CkCert
$cert = $certStore->FindCertBySubjectCN($signingCertSubject);
if ($certStore->get_LastMethodSuccess() == false) {
    print 'Failed to find certificate by subject common name.' . "\n";
    exit;
}

// Tell the crypt component to use this cert.
$success = $crypt->SetSigningCert($cert);

// We can sign any type of file, creating a .p7s as output:
$inFile = '/Users/chilkat/testData/pdf/sample.pdf';
$sigFile = '/Users/chilkat/testData/p7s/sample.p7s';

$success = $crypt->CreateP7S($inFile,$sigFile);
if ($success == false) {
    print $crypt->lastErrorText() . "\n";

    exit;
}

$success = $crypt->VerifyP7S($inFile,$sigFile);
if ($success == false) {
    print $crypt->lastErrorText() . "\n";

    exit;
}

print 'Success!' . "\n";

?>