/home/preegmxb/byeaglytics-co.com/libraries/vendor/web-auth/cose-lib/src/Algorithm/Mac/Hmac.php
<?php
declare(strict_types=1);
/*
* The MIT License (MIT)
*
* Copyright (c) 2014-2019 Spomky-Labs
*
* This software may be modified and distributed under the terms
* of the MIT license. See the LICENSE file for details.
*/
namespace Cose\Algorithm\Mac;
use Assert\Assertion;
use Cose\Key\Key;
abstract class Hmac implements Mac
{
public function hash(string $data, Key $key): string
{
$this->checKey($key);
$signature = hash_hmac($this->getHashAlgorithm(), $data, $key->get(-1), true);
return mb_substr($signature, 0, $this->getSignatureLength() / 8, '8bit');
}
public function verify(string $data, Key $key, string $signature): bool
{
return hash_equals($this->hash($data, $key), $signature);
}
private function checKey(Key $key): void
{
Assertion::eq($key->type(), 4, 'Invalid key. Must be of type symmetric');
Assertion::true($key->has(-1), 'Invalid key. The value of the key is missing');
}
abstract protected function getHashAlgorithm(): string;
abstract protected function getSignatureLength(): int;
}