Subversion-Projekte lars-tiefland.ci

<?php

/**

 * CodeIgniter

 *

 * An open source application development framework for PHP

 *

 * This content is released under the MIT License (MIT)

 *

 * Copyright (c) 2014 - 2018, British Columbia Institute of Technology

 *

 * Permission is hereby granted, free of charge, to any person obtaining a copy

 * of this software and associated documentation files (the "Software"), to deal

 * in the Software without restriction, including without limitation the rights

 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

 * copies of the Software, and to permit persons to whom the Software is

 * furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice shall be included in

 * all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

 * THE SOFTWARE.

 *

 * @package	CodeIgniter

 * @author	EllisLab Dev Team

 * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/)

 * @copyright	Copyright (c) 2014 - 2018, British Columbia Institute of Technology (http://bcit.ca/)

 * @license	http://opensource.org/licenses/MIT	MIT License

 * @link	https://codeigniter.com

 * @since	Version 3.0.0

 * @filesource

 */

defined('BASEPATH') OR exit('No direct script access allowed');

/**

 * PHP ext/hash compatibility package

 *

 * @package		CodeIgniter

 * @subpackage	CodeIgniter

 * @category	Compatibility

 * @author		Andrey Andreev

 * @link		https://codeigniter.com/user_guide/

 * @link		http://php.net/hash

 */

// ------------------------------------------------------------------------

if (is_php('5.6'))

{

	return;

}

// ------------------------------------------------------------------------

if ( ! function_exists('hash_equals'))

{

	/**

	 * hash_equals()

	 *

	 * @link	http://php.net/hash_equals

	 * @param	string	$known_string

	 * @param	string	$user_string

	 * @return	bool

	 */

	function hash_equals($known_string, $user_string)

	{

		if ( ! is_string($known_string))

		{

			trigger_error('hash_equals(): Expected known_string to be a string, '.strtolower(gettype($known_string)).' given', E_USER_WARNING);

			return FALSE;

		}

		elseif ( ! is_string($user_string))

		{

			trigger_error('hash_equals(): Expected user_string to be a string, '.strtolower(gettype($user_string)).' given', E_USER_WARNING);

			return FALSE;

		}

		elseif (($length = strlen($known_string)) !== strlen($user_string))

		{

			return FALSE;

		}

		$diff = 0;

		for ($i = 0; $i < $length; $i++)

		{

			$diff |= ord($known_string[$i]) ^ ord($user_string[$i]);

		}

		return ($diff === 0);

	}

}

// ------------------------------------------------------------------------

if (is_php('5.5'))

{

	return;

}

// ------------------------------------------------------------------------

if ( ! function_exists('hash_pbkdf2'))

{

	/**

	 * hash_pbkdf2()

	 *

	 * @link	http://php.net/hash_pbkdf2

	 * @param	string	$algo

	 * @param	string	$password

	 * @param	string	$salt

	 * @param	int	$iterations

	 * @param	int	$length

	 * @param	bool	$raw_output

	 * @return	string

	 */

	function hash_pbkdf2($algo, $password, $salt, $iterations, $length = 0, $raw_output = FALSE)

	{

		if ( ! in_array(strtolower($algo), hash_algos(), TRUE))

		{

			trigger_error('hash_pbkdf2(): Unknown hashing algorithm: '.$algo, E_USER_WARNING);

			return FALSE;

		}

		if (($type = gettype($iterations)) !== 'integer')

		{

			if ($type === 'object' && method_exists($iterations, '__toString'))

			{

				$iterations = (string) $iterations;

			}

			if (is_string($iterations) && is_numeric($iterations))

			{

				$iterations = (int) $iterations;

			}

			else

			{

				trigger_error('hash_pbkdf2() expects parameter 4 to be long, '.$type.' given', E_USER_WARNING);

				return NULL;

			}

		}

		if ($iterations < 1)

		{

			trigger_error('hash_pbkdf2(): Iterations must be a positive integer: '.$iterations, E_USER_WARNING);

			return FALSE;

		}

		if (($type = gettype($length)) !== 'integer')

		{

			if ($type === 'object' && method_exists($length, '__toString'))

			{

				$length = (string) $length;

			}

			if (is_string($length) && is_numeric($length))

			{

				$length = (int) $length;

			}

			else

			{

				trigger_error('hash_pbkdf2() expects parameter 5 to be long, '.$type.' given', E_USER_WARNING);

				return NULL;

			}

		}

		if ($length < 0)

		{

			trigger_error('hash_pbkdf2(): Length must be greater than or equal to 0: '.$length, E_USER_WARNING);

			return FALSE;

		}

		$hash_length = defined('MB_OVERLOAD_STRING')

			? mb_strlen(hash($algo, NULL, TRUE), '8bit')

			: strlen(hash($algo, NULL, TRUE));

		empty($length) && $length = $hash_length;

		// Pre-hash password inputs longer than the algorithm's block size

		// (i.e. prepare HMAC key) to mitigate potential DoS attacks.

		static $block_sizes;

		empty($block_sizes) && $block_sizes = array(

			'gost' => 32,

			'haval128,3' => 128,

			'haval160,3' => 128,

			'haval192,3' => 128,

			'haval224,3' => 128,

			'haval256,3' => 128,

			'haval128,4' => 128,

			'haval160,4' => 128,

			'haval192,4' => 128,

			'haval224,4' => 128,

			'haval256,4' => 128,

			'haval128,5' => 128,

			'haval160,5' => 128,

			'haval192,5' => 128,

			'haval224,5' => 128,

			'haval256,5' => 128,

			'md2' => 16,

			'md4' => 64,

			'md5' => 64,

			'ripemd128' => 64,

			'ripemd160' => 64,

			'ripemd256' => 64,

			'ripemd320' => 64,

			'salsa10' => 64,

			'salsa20' => 64,

			'sha1' => 64,

			'sha224' => 64,

			'sha256' => 64,

			'sha384' => 128,

			'sha512' => 128,

			'snefru' => 32,

			'snefru256' => 32,

			'tiger128,3' => 64,

			'tiger160,3' => 64,

			'tiger192,3' => 64,

			'tiger128,4' => 64,

			'tiger160,4' => 64,

			'tiger192,4' => 64,

			'whirlpool' => 64

		);

		if (isset($block_sizes[$algo], $password[$block_sizes[$algo]]))

		{

			$password = hash($algo, $password, TRUE);

		}

		$hash = '';

		// Note: Blocks are NOT 0-indexed

		for ($bc = (int) ceil($length / $hash_length), $bi = 1; $bi <= $bc; $bi++)

		{

			$key = $derived_key = hash_hmac($algo, $salt.pack('N', $bi), $password, TRUE);

			for ($i = 1; $i < $iterations; $i++)

			{

				$derived_key ^= $key = hash_hmac($algo, $key, $password, TRUE);

			}

			$hash .= $derived_key;

		}

		// This is not RFC-compatible, but we're aiming for natural PHP compatibility

		if ( ! $raw_output)

		{

			$hash = bin2hex($hash);

		}

		return defined('MB_OVERLOAD_STRING')

			? mb_substr($hash, 0, $length, '8bit')

			: substr($hash, 0, $length);

	}

}