- var_dump: documentation ( source)
- hash_hmac: documentation ( source)
- hash_equals: documentation ( source)
- base64_encode: documentation ( source)
<?php
$message = 'Message';
$secret = 'secret';
$hash = hash_hmac('sha256', $message, $secret, true);
$encoded = base64_encode($hash);
var_dump(hash_equals($hash, $encoded));