1<?php 2 3/** 4 * Pure-PHP implementation of AES. 5 * 6 * Uses mcrypt, if available/possible, and an internal implementation, otherwise. 7 * 8 * PHP version 5 9 * 10 * NOTE: Since AES.php is (for compatibility and phpseclib-historical reasons) virtually 11 * just a wrapper to Rijndael.php you may consider using Rijndael.php instead of 12 * to save one include_once(). 13 * 14 * If {@link self::setKeyLength() setKeyLength()} isn't called, it'll be calculated from 15 * {@link self::setKey() setKey()}. ie. if the key is 128-bits, the key length will be 128-bits. If it's 136-bits 16 * it'll be null-padded to 192-bits and 192 bits will be the key length until {@link self::setKey() setKey()} 17 * is called, again, at which point, it'll be recalculated. 18 * 19 * Since \phpseclib3\Crypt\AES extends \phpseclib3\Crypt\Rijndael, some functions are available to be called that, in the context of AES, don't 20 * make a whole lot of sense. {@link self::setBlockLength() setBlockLength()}, for instance. Calling that function, 21 * however possible, won't do anything (AES has a fixed block length whereas Rijndael has a variable one). 22 * 23 * Here's a short example of how to use this library: 24 * <code> 25 * <?php 26 * include 'vendor/autoload.php'; 27 * 28 * $aes = new \phpseclib3\Crypt\AES('ctr'); 29 * 30 * $aes->setKey('abcdefghijklmnop'); 31 * 32 * $size = 10 * 1024; 33 * $plaintext = ''; 34 * for ($i = 0; $i < $size; $i++) { 35 * $plaintext.= 'a'; 36 * } 37 * 38 * echo $aes->decrypt($aes->encrypt($plaintext)); 39 * ?> 40 * </code> 41 * 42 * @category Crypt 43 * @package AES 44 * @author Jim Wigginton <terrafrost@php.net> 45 * @copyright 2008 Jim Wigginton 46 * @license http://www.opensource.org/licenses/mit-license.html MIT License 47 * @link http://phpseclib.sourceforge.net 48 */ 49 50namespace phpseclib3\Crypt; 51 52/** 53 * Pure-PHP implementation of AES. 54 * 55 * @package AES 56 * @author Jim Wigginton <terrafrost@php.net> 57 * @access public 58 */ 59class AES extends Rijndael 60{ 61 /** 62 * Dummy function 63 * 64 * Since \phpseclib3\Crypt\AES extends \phpseclib3\Crypt\Rijndael, this function is, technically, available, but it doesn't do anything. 65 * 66 * @see \phpseclib3\Crypt\Rijndael::setBlockLength() 67 * @access public 68 * @param int $length 69 * @throws \BadMethodCallException anytime it's called 70 */ 71 public function setBlockLength($length) 72 { 73 throw new \BadMethodCallException('The block length cannot be set for AES.'); 74 } 75 76 /** 77 * Sets the key length 78 * 79 * Valid key lengths are 128, 192, and 256. Set the link to bool(false) to disable a fixed key length 80 * 81 * @see \phpseclib3\Crypt\Rijndael:setKeyLength() 82 * @access public 83 * @param int $length 84 * @throws \LengthException if the key length isn't supported 85 */ 86 public function setKeyLength($length) 87 { 88 switch ($length) { 89 case 128: 90 case 192: 91 case 256: 92 break; 93 default: 94 throw new \LengthException('Key of size ' . $length . ' not supported by this algorithm. Only keys of sizes 128, 192 or 256 supported'); 95 } 96 parent::setKeyLength($length); 97 } 98 99 /** 100 * Sets the key. 101 * 102 * Rijndael supports five different key lengths, AES only supports three. 103 * 104 * @see \phpseclib3\Crypt\Rijndael:setKey() 105 * @see setKeyLength() 106 * @access public 107 * @param string $key 108 * @throws \LengthException if the key length isn't supported 109 */ 110 public function setKey($key) 111 { 112 switch (strlen($key)) { 113 case 16: 114 case 24: 115 case 32: 116 break; 117 default: 118 throw new \LengthException('Key of size ' . strlen($key) . ' not supported by this algorithm. Only keys of sizes 16, 24 or 32 supported'); 119 } 120 121 parent::setKey($key); 122 } 123} 124