<?php | |
/** | |
* Pure-PHP implementation of AES. | |
* | |
* Uses mcrypt, if available/possible, and an internal implementation, otherwise. | |
* | |
* PHP versions 4 and 5 | |
* | |
* NOTE: Since AES.php is (for compatibility and phpseclib-historical reasons) virtually | |
* just a wrapper to Rijndael.php you may consider using Rijndael.php instead of | |
* to save one include_once(). | |
* | |
* If {@link self::setKeyLength() setKeyLength()} isn't called, it'll be calculated from | |
* {@link self::setKey() setKey()}. ie. if the key is 128-bits, the key length will be 128-bits. If it's 136-bits | |
* it'll be null-padded to 192-bits and 192 bits will be the key length until {@link self::setKey() setKey()} | |
* is called, again, at which point, it'll be recalculated. | |
* | |
* Since Crypt_AES extends Crypt_Rijndael, some functions are available to be called that, in the context of AES, don't | |
* make a whole lot of sense. {@link self::setBlockLength() setBlockLength()}, for instance. Calling that function, | |
* however possible, won't do anything (AES has a fixed block length whereas Rijndael has a variable one). | |
* | |
* Here's a short example of how to use this library: | |
* <code> | |
* <?php | |
* include 'Crypt/AES.php'; | |
* | |
* $aes = new Crypt_AES(); | |
* | |
* $aes->setKey('abcdefghijklmnop'); | |
* | |
* $size = 10 * 1024; | |
* $plaintext = ''; | |
* for ($i = 0; $i < $size; $i++) { | |
* $plaintext.= 'a'; | |
* } | |
* | |
* echo $aes->decrypt($aes->encrypt($plaintext)); | |
* ?> | |
* </code> | |
* | |
* LICENSE: 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. | |
* | |
* @category Crypt | |
* @package Crypt_AES | |
* @author Jim Wigginton <terrafrost@php.net> | |
* @copyright 2008 Jim Wigginton | |
* @license http://www.opensource.org/licenses/mit-license.html MIT License | |
* @link http://phpseclib.sourceforge.net | |
*/ | |
/** | |
* Include Crypt_Rijndael | |
*/ | |
if (!class_exists('Crypt_Rijndael')) { | |
include_once 'Rijndael.php'; | |
} | |
/**#@+ | |
* @access public | |
* @see self::encrypt() | |
* @see self::decrypt() | |
*/ | |
/** | |
* Encrypt / decrypt using the Counter mode. | |
* | |
* Set to -1 since that's what Crypt/Random.php uses to index the CTR mode. | |
* | |
* @link http://en.wikipedia.org/wiki/Block_cipher_modes_of_operation#Counter_.28CTR.29 | |
*/ | |
define('CRYPT_AES_MODE_CTR', CRYPT_MODE_CTR); | |
/** | |
* Encrypt / decrypt using the Electronic Code Book mode. | |
* | |
* @link http://en.wikipedia.org/wiki/Block_cipher_modes_of_operation#Electronic_codebook_.28ECB.29 | |
*/ | |
define('CRYPT_AES_MODE_ECB', CRYPT_MODE_ECB); | |
/** | |
* Encrypt / decrypt using the Code Book Chaining mode. | |
* | |
* @link http://en.wikipedia.org/wiki/Block_cipher_modes_of_operation#Cipher-block_chaining_.28CBC.29 | |
*/ | |
define('CRYPT_AES_MODE_CBC', CRYPT_MODE_CBC); | |
/** | |
* Encrypt / decrypt using the Cipher Feedback mode. | |
* | |
* @link http://en.wikipedia.org/wiki/Block_cipher_modes_of_operation#Cipher_feedback_.28CFB.29 | |
*/ | |
define('CRYPT_AES_MODE_CFB', CRYPT_MODE_CFB); | |
/** | |
* Encrypt / decrypt using the Cipher Feedback mode. | |
* | |
* @link http://en.wikipedia.org/wiki/Block_cipher_modes_of_operation#Output_feedback_.28OFB.29 | |
*/ | |
define('CRYPT_AES_MODE_OFB', CRYPT_MODE_OFB); | |
/**#@-*/ | |
/** | |
* Pure-PHP implementation of AES. | |
* | |
* @package Crypt_AES | |
* @author Jim Wigginton <terrafrost@php.net> | |
* @access public | |
*/ | |
class Crypt_AES extends Crypt_Rijndael | |
{ | |
/** | |
* The namespace used by the cipher for its constants. | |
* | |
* @see Crypt_Base::const_namespace | |
* @var string | |
* @access private | |
*/ | |
var $const_namespace = 'AES'; | |
/** | |
* Dummy function | |
* | |
* Since Crypt_AES extends Crypt_Rijndael, this function is, technically, available, but it doesn't do anything. | |
* | |
* @see Crypt_Rijndael::setBlockLength() | |
* @access public | |
* @param int $length | |
*/ | |
function setBlockLength($length) | |
{ | |
return; | |
} | |
/** | |
* Sets the key length | |
* | |
* Valid key lengths are 128, 192, and 256. If the length is less than 128, it will be rounded up to | |
* 128. If the length is greater than 128 and invalid, it will be rounded down to the closest valid amount. | |
* | |
* @see Crypt_Rijndael:setKeyLength() | |
* @access public | |
* @param int $length | |
*/ | |
function setKeyLength($length) | |
{ | |
switch ($length) { | |
case 160: | |
$length = 192; | |
break; | |
case 224: | |
$length = 256; | |
} | |
parent::setKeyLength($length); | |
} | |
/** | |
* Sets the key. | |
* | |
* Rijndael supports five different key lengths, AES only supports three. | |
* | |
* @see Crypt_Rijndael:setKey() | |
* @see setKeyLength() | |
* @access public | |
* @param string $key | |
*/ | |
function setKey($key) | |
{ | |
parent::setKey($key); | |
if (!$this->explicit_key_length) { | |
$length = strlen($key); | |
switch (true) { | |
case $length <= 16: | |
$this->key_length = 16; | |
break; | |
case $length <= 24: | |
$this->key_length = 24; | |
break; | |
default: | |
$this->key_length = 32; | |
} | |
$this->_setEngine(); | |
} | |
} | |
} |