File size: 1.81Kb
<?php
declare(strict_types=1);
/*
* The MIT License (MIT)
*
* Copyright (c) 2014-2020 Spomky-Labs
*
* This software may be modified and distributed under the terms
* of the MIT license. See the LICENSE file for details.
*/
namespace Jose\Component\Encryption\Algorithm\KeyEncryption;
use Base64Url\Base64Url;
use function in_array;
use InvalidArgumentException;
use function is_string;
use Jose\Component\Core\JWK;
abstract class AESKW implements KeyWrapping
{
public function allowedKeyTypes(): array
{
return ['oct'];
}
public function wrapKey(JWK $key, string $cek, array $completeHeader, array &$additionalHeader): string
{
$k = $this->getKey($key);
$wrapper = $this->getWrapper();
return $wrapper::wrap($k, $cek);
}
public function unwrapKey(JWK $key, string $encrypted_cek, array $completeHeader): string
{
$k = $this->getKey($key);
$wrapper = $this->getWrapper();
return $wrapper::unwrap($k, $encrypted_cek);
}
public function getKeyManagementMode(): string
{
return self::MODE_WRAP;
}
/**
* @return \AESKW\A128KW|\AESKW\A192KW|\AESKW\A256KW
*/
abstract protected function getWrapper();
/**
* @throws InvalidArgumentException if the key is invalid
*/
private function getKey(JWK $key): string
{
if (!in_array($key->get('kty'), $this->allowedKeyTypes(), true)) {
throw new InvalidArgumentException('Wrong key type.');
}
if (!$key->has('k')) {
throw new InvalidArgumentException('The key parameter "k" is missing.');
}
$k = $key->get('k');
if (!is_string($k)) {
throw new InvalidArgumentException('The key parameter "k" is invalid.');
}
return Base64Url::decode($k);
}
}