<?php
/**
* CodeIgniter
*
* An open source application development framework for PHP
*
* This content is released under the MIT License (MIT)
*
* Copyright (c) 2014 - 2015, 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. (http://ellislab.com/)
* @copyright Copyright (c) 2014 - 2015, British Columbia Institute of Technology (http://bcit.ca/)
* @license http://opensource.org/licenses/MIT MIT License
* @link http://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 http://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, $raw_output = FALSE)
{
if ( ! in_array($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;
}
$hash_length = strlen(hash($algo, NULL, TRUE));
if (empty($length))
{
$length = $hash_length;
}
$hash = '';
// Note: Blocks are NOT 0-indexed
for ($bc = 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 .= $derived_key;
}
// This is not RFC-compatible, but we're aiming for natural PHP compatibility
return substr($raw_output ? $hash : bin2hex($hash), 0, $length);
}
}