laipower/wp-content/plugins/wp-webauthn/vendor/web-token/jwt-key-mgmt/Analyzer/RsaAnalyzer.php

55 lines
1.7 KiB
PHP

<?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\KeyManagement\Analyzer;
use Base64Url\Base64Url;
use InvalidArgumentException;
use function is_array;
use Jose\Component\Core\JWK;
final class RsaAnalyzer implements KeyAnalyzer
{
public function analyze(JWK $jwk, MessageBag $bag): void
{
if ('RSA' !== $jwk->get('kty')) {
return;
}
$this->checkExponent($jwk, $bag);
$this->checkModulus($jwk, $bag);
}
private function checkExponent(JWK $jwk, MessageBag $bag): void
{
$exponent = unpack('l', str_pad(Base64Url::decode($jwk->get('e')), 4, "\0"));
if (!is_array($exponent) || !isset($exponent[1])) {
throw new InvalidArgumentException('Unable to get the private key');
}
if ($exponent[1] < 65537) {
$bag->add(Message::high('The exponent is too low. It should be at least 65537.'));
}
}
private function checkModulus(JWK $jwk, MessageBag $bag): void
{
$n = 8 * mb_strlen(Base64Url::decode($jwk->get('n')), '8bit');
if ($n < 2048) {
$bag->add(Message::high('The key length is less than 2048 bits.'));
}
if ($jwk->has('d') && (!$jwk->has('p') || !$jwk->has('q') || !$jwk->has('dp') || !$jwk->has('dq') || !$jwk->has('p') || !$jwk->has('qi'))) {
$bag->add(Message::medium('The key is a private RSA key, but Chinese Remainder Theorem primes are missing. These primes are not mandatory, but signatures and decryption processes are faster when available.'));
}
}
}