nextcloud/lib/public/security/isecurerandom.php

75 lines
2.5 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 OCP\Security;
/**
* Class SecureRandom provides a layer around RandomLib to generate
* secure random numbers.
*
* Usage:
* $rng = new \OC\Security\SecureRandom();
* $randomString = $rng->getMediumStrengthGenerator()->generateString(30);
*
* @package OCP\Security
*/
interface ISecureRandom {
/**
* Flags for characters that can be used for <code>generate($length, $characters)</code>
*/
const CHAR_UPPER = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
const CHAR_LOWER = 'abcdefghijklmnopqrstuvwxyz';
const CHAR_DIGITS = '0123456789';
const CHAR_SYMBOLS = '!\"#$%&\\\'()* +,-./:;<=>?@[\]^_`{|}~';
/**
* Convenience method to get a low strength random number generator.
*
* Low Strength should be used anywhere that random strings are needed
* in a non-cryptographical setting. They are not strong enough to be
* used as keys or salts. They are however useful for one-time use tokens.
*
* @return $this
*/
public function getLowStrengthGenerator();
/**
* Convenience method to get a medium strength random number generator.
*
* Medium Strength should be used for most needs of a cryptographic nature.
* They are strong enough to be used as keys and salts. However, they do
* take some time and resources to generate, so they should not be over-used
*
* @return $this
*/
public function getMediumStrengthGenerator();
/**
* Generate a random string of specified length.
* @param string $length The length of the generated string
* @param string $characters An optional list of characters to use if no characterlist is
* specified all valid base64 characters are used.
* @return string
* @throws \Exception If the generator is not initialized.
*/
public function generate($length, $characters = '');
}