CommunityID/libs/Zend/InfoCard/Cipher/Symmetric/Adapter/Aes256cbc.php

115 lines
3.6 KiB
PHP

<?php
/**
* Zend Framework
*
* LICENSE
*
* This source file is subject to the new BSD license that is bundled
* with this package in the file LICENSE.txt.
* It is also available through the world-wide-web at this URL:
* http://framework.zend.com/license/new-bsd
* If you did not receive a copy of the license and are unable to
* obtain it through the world-wide-web, please send an email
* to license@zend.com so we can send you a copy immediately.
*
* @category Zend
* @package Zend_InfoCard
* @subpackage Zend_InfoCard_Cipher
* @copyright Copyright (c) 2005-2008 Zend Technologies USA Inc. (http://www.zend.com)
* @license http://framework.zend.com/license/new-bsd New BSD License
* @version $Id: Aes256cbc.php 9094 2008-03-30 18:36:55Z thomas $
*/
/**
* Zend_InfoCard_Cipher_Symmetric_Adapter_Abstract
*/
require_once 'Zend/InfoCard/Cipher/Symmetric/Adapter/Abstract.php';
/**
* Zend_InfoCard_Cipher_Symmetric_Aes256cbc_Interface
*/
require_once 'Zend/InfoCard/Cipher/Symmetric/Aes256cbc/Interface.php';
/**
* Zend_InfoCard_Cipher_Exception
*/
require_once 'Zend/InfoCard/Cipher/Exception.php';
/**
* Implements AES256 with CBC encryption implemented using the mCrypt extension
*
* @category Zend
* @package Zend_InfoCard
* @subpackage Zend_InfoCard_Cipher
* @copyright Copyright (c) 2005-2008 Zend Technologies USA Inc. (http://www.zend.com)
* @license http://framework.zend.com/license/new-bsd New BSD License
*/
class Zend_InfoCard_Cipher_Symmetric_Adapter_Aes256cbc
extends Zend_InfoCard_Cipher_Symmetric_Adapter_Abstract
implements Zend_InfoCard_Cipher_Symmetric_Aes256cbc_Interface
{
/**
* The MCRYPT Cipher constant for this encryption
*/
const MCRYPT_CIPHER = MCRYPT_RIJNDAEL_128;
/**
* The MCRYPT Mode constant for this encryption
*/
const MCRYPT_MODE = MCRYPT_MODE_CBC;
/**
* The default length of the IV to use
*/
const IV_LENGTH = 16;
/**
* The object constructor
*
* @throws Zend_InfoCard_Cipher_Exception
*/
public function __construct()
{
// Can't test for this
// @codeCoverageIgnoreStart
if(!extension_loaded('mcrypt')) {
throw new Zend_InfoCard_Cipher_Exception("Use of the AES256CBC Cipher requires the mcrypt extension");
}
// @codeCoveregIgnoreEnd
}
/**
* Decrypts data using the AES Algorithm using the mCrypt extension
*
* @throws Zend_InfoCard_Cipher_Exception
* @param string $encryptedData The encrypted data in binary format
* @param string $decryptionKey The decryption key
* @param integer $iv_length The IV length to use
* @return string the decrypted data with any terminating nulls removed
*/
public function decrypt($encryptedData, $decryptionKey, $iv_length = null)
{
$iv_length = is_null($iv_length) ? self::IV_LENGTH : $iv_length;
$mcrypt_iv = null;
if($iv_length > 0) {
$mcrypt_iv = substr($encryptedData, 0, $iv_length);
$encryptedData = substr($encryptedData, $iv_length);
}
$decrypted = mcrypt_decrypt(self::MCRYPT_CIPHER, $decryptionKey, $encryptedData, self::MCRYPT_MODE, $mcrypt_iv);
if(!$decrypted) {
throw new Zend_InfoCard_Cipher_Exception("Failed to decrypt data using AES256CBC Algorithm");
}
$decryptedLength = strlen($decrypted);
$paddingLength = substr($decrypted, $decryptedLength -1, 1);
$decrypted = substr($decrypted, 0, $decryptedLength - ord($paddingLength));
return rtrim($decrypted, "\0");
}
}