Validate a JWS with a Public Key

See more JSON Web Signatures (JWS) Examples

Demonstrates Jws.SetPublicKey, which sets the public key used to validate a signature of a loaded JWS.

The file path is relative to the application's current working directory. An absolute path may also be used. Supply the path appropriate to your own environment.

<?php

include("chilkat.php");

$success = false;

$jws = new CkJws();

//  Load the JWS compact serialization.
$jwsCompact = 'eyJhbGciOiJIUzI1NiJ9.VGhpcyBpcyB0aGUgY29udGVudCB0byBzaWduLg.<signature>';
$success = $jws->LoadJws($jwsCompact);
if ($success == false) {
    print $jws->lastErrorText() . "\n";
    exit;
}

//  The file path is relative to the application's current working directory.  An absolute path
//  may also be used.  Supply the path appropriate to your own environment.
//  Load the signer's public key and set it for validating signature 0.
$pubKey = new CkPublicKey();
$success = $pubKey->LoadFromFile('qa_data/signer_pubkey.pem');
if ($success == false) {
    print $pubKey->lastErrorText() . "\n";
    exit;
}

$success = $jws->SetPublicKey(0,$pubKey);
if ($success == false) {
    print $jws->lastErrorText() . "\n";
    exit;
}

//  Validate the signature.  Validate returns 1 when valid, 0 when not, or a negative value on error.
$v = $jws->Validate(0);
if ($v < 0) {
    print $jws->lastErrorText() . "\n";
    exit;
}

if ($v != 1) {
    print 'The signature is not valid.' . "\n";
    exit;
}

print 'The signature is valid.' . "\n";

?>