PHP Extension

Create an Opaque Signature with a Separate Private Key

Demonstrates the Chilkat Mime.ConvertToSignedPk method, which creates an opaque signature using a signer certificate and its separately supplied private key. The first argument is the Cert and the second is the PrivateKey.

Note: The file paths are relative to the application's current working directory. Absolute paths may also be used. Supply the paths appropriate to your own environment.

Background: The separate-key form of ConvertToSigned, for when the certificate and private key are not bundled together. It produces the same opaque CMS signed-data result; only the source of the key material differs.

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PHP Extension

<?php

include("chilkat.php");

$success = false;

$mime = new CkMime();
$success = $mime->SetBodyFromPlainText('This message will be signed.');
if ($success == false) {
    print $mime->lastErrorText() . "\n";
    exit;
}

//  Load the certificate and its private key separately.
$cert = new CkCert();
$success = $cert->LoadFromFile('qa_data/signer.cer');
if ($success == false) {
    print $cert->lastErrorText() . "\n";
    exit;
}

$privKey = new CkPrivateKey();
$success = $privKey->LoadPemFile('qa_data/signer_privkey.pem');
if ($success == false) {
    print $privKey->lastErrorText() . "\n";
    exit;
}

//  Create an opaque signature when the certificate and private key are supplied separately.  The
//  1st argument is the signer certificate and the 2nd is its private key.
$success = $mime->ConvertToSignedPk($cert,$privKey);
if ($success == false) {
    print $mime->lastErrorText() . "\n";
    exit;
}

$success = $mime->SaveMime('qa_output/signed_opaque.eml');
if ($success == false) {
    print $mime->lastErrorText() . "\n";
    exit;
}

print 'Message converted to an opaque signed message.' . "\n";

?>