<?php /* * This file is part of the Symfony package. * * (c) Fabien Potencier <fabien@symfony.com> * * For the full copyright and license information, please view the LICENSE * file that was distributed with this source code. */ namespace Symfony\Component\HttpKernel; /** * Signs URIs. * * @author Fabien Potencier <fabien@symfony.com> */ class UriSigner { private $secret; /** * Constructor. * * @param string $secret A secret */ public function __construct($secret) { $this->secret = $secret; } /** * Signs a URI. * * The given URI is signed by adding a _hash query string parameter * which value depends on the URI and the secret. * * @param string $uri A URI to sign * * @return string The signed URI */ public function sign($uri) { return $uri.(false === (strpos($uri, '?')) ? '?' : '&').'_hash='.$this->computeHash($uri); } /** * Checks that a URI contains the correct hash. * * The _hash query string parameter must be the last one * (as it is generated that way by the sign() method, it should * never be a problem). * * @param string $uri A signed URI * * @return Boolean True if the URI is signed correctly, false otherwise */ public function check($uri) { if (!preg_match('/^(.*)(?:\?|&)_hash=(.+?)$/', $uri, $matches)) { return false; } return $this->computeHash($matches[1]) === $matches[2]; } private function computeHash($uri) { return urlencode(base64_encode(hash_hmac('sha256', $uri, $this->secret, true))); } }