58 lines
1.8 KiB
PHP
58 lines
1.8 KiB
PHP
<?php
|
|
/**
|
|
* @author Lukas Reschke <lukas@owncloud.com>
|
|
*
|
|
* @copyright Copyright (c) 2015, ownCloud, Inc.
|
|
* @license AGPL-3.0
|
|
*
|
|
* This code is free software: you can redistribute it and/or modify
|
|
* it under the terms of the GNU Affero General Public License, version 3,
|
|
* as published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU Affero General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Affero General Public License, version 3,
|
|
* along with this program. If not, see <http://www.gnu.org/licenses/>
|
|
*
|
|
*/
|
|
namespace OC\Security;
|
|
|
|
class StringUtils {
|
|
|
|
/**
|
|
* Compares whether two strings are equal. To prevent guessing of the string
|
|
* length this is done by comparing two hashes against each other and afterwards
|
|
* a comparison of the real string to prevent against the unlikely chance of
|
|
* collisions.
|
|
*
|
|
* Be aware that this function may leak whether the string to compare have a different
|
|
* length.
|
|
*
|
|
* @param string $expected The expected value
|
|
* @param string $input The input to compare against
|
|
* @return bool True if the two strings are equal, otherwise false.
|
|
*/
|
|
public static function equals($expected, $input) {
|
|
|
|
if(!is_string($expected) || !is_string($input)) {
|
|
return false;
|
|
}
|
|
|
|
if(function_exists('hash_equals')) {
|
|
return hash_equals($expected, $input);
|
|
}
|
|
|
|
$randomString = \OC::$server->getSecureRandom()->getLowStrengthGenerator()->generate(10);
|
|
|
|
if(hash('sha512', $expected.$randomString) === hash('sha512', $input.$randomString)) {
|
|
if($expected === $input) {
|
|
return true;
|
|
}
|
|
}
|
|
|
|
return false;
|
|
}
|
|
} |