(PHP Extension) RSA Signature with Certificate's Private Key from PFX

See more RSA Examples

Demonstrates how to use a certificate's private key from a PFX file to create an RSA signature.

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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.

// Create an instance of a certificate store object, load a PFX file,
// locate the certificate we need, and use it for signing.
// (a PFX file may contain more than one certificate.)
$certStore = new CkCertStore();

// The 1st argument is the filename, the 2nd arg is the 
// PFX file's password:
$success = $certStore->LoadPfxFile('chilkat.pfx','test');
if ($success != true) {
    print $certStore->lastErrorText() . "\n";
    exit;
}

// cert is a CkCert
$cert = $certStore->FindCertBySubject('Chilkat Software, Inc.');
if ($certStore->get_LastMethodSuccess() == false) {
    print $certStore->lastErrorText() . "\n";
    exit;
}

// pkey is a CkPrivateKey
$pkey = $cert->ExportPrivateKey();
if ($cert->get_LastMethodSuccess() == false) {
    print $cert->lastErrorText() . "\n";

    exit;
}

// Get the private key in XML format:
$pkeyXml = $pkey->getXml();

$rsa = new CkRsa();

// Import the private key into the RSA component:
$success = $rsa->ImportPrivateKey($pkeyXml);
if ($success != true) {
    print $rsa->lastErrorText() . "\n";

    exit;
}

// Encode the signature as a hex string
$rsa->put_EncodingMode('hex');

$strData = 'This is the string to be signed.';

// Sign the string using the sha-1 hash algorithm.
// Other valid choices are "sha-256", "md2" and "md5".
$hexSig = $rsa->signStringENC($strData,'sha-1');

print $hexSig . "\n";

print 'Success!' . "\n";

?>