| 1 | <?php |
| 2 | /** |
| 3 | * An implementation of the TripleDES cipher |
| 4 | * |
| 5 | * This was forked from phpseclib and modified to use CryptLib conventions |
| 6 | * |
| 7 | * PHP version 5.3 |
| 8 | * |
| 9 | * @category PHPCryptLib |
| 10 | * @package Cipher |
| 11 | * @subpackage Block |
| 12 | * @author Anthony Ferrara <ircmaxell@ircmaxell.com> |
| 13 | * @author Jim Wigginton <terrafrost@php.net> |
| 14 | * @copyright 2011 The Authors |
| 15 | * @license http://www.opensource.org/licenses/mit-license.html MIT License |
| 16 | * @version Build @@version@@ |
| 17 | */ |
| 18 | |
| 19 | namespace CryptLib\Cipher\Block\Cipher; |
| 20 | |
| 21 | /** |
| 22 | * An implementation of the TripleDES Cipher |
| 23 | * |
| 24 | * @category PHPCryptLib |
| 25 | * @package Cipher |
| 26 | * @subpackage Block |
| 27 | * @author Anthony Ferrara <ircmaxell@ircmaxell.com> |
| 28 | */ |
| 29 | class TripleDES extends DES { |
| 30 | |
| 31 | /** |
| 32 | * @var int The key size for the cipher |
| 33 | */ |
| 34 | protected $keySize = 24; |
| 35 | |
| 36 | /** |
| 37 | * Get a list of supported ciphers for this class implementation |
| 38 | * |
| 39 | * @return array A list of supported ciphers |
| 40 | */ |
| 41 | public static function getSupportedCiphers() { |
| 42 | return array('tripledes'); |
| 43 | } |
| 44 | |
| 45 | /** |
| 46 | * Set the key to use for the cipher |
| 47 | * |
| 48 | * @param string $key The key to use |
| 49 | * |
| 50 | * @throws InvalidArgumentException If the key is not the correct size |
| 51 | * @return void |
| 52 | */ |
| 53 | public function setKey($key) { |
| 54 | $len = strlen($key); |
| 55 | if ($len == 16) { |
| 56 | $key .= substr($key, 0, 8); |
| 57 | } elseif ($len != 24) { |
| 58 | throw new \InvalidArgumentException( |
| 59 | 'The supplied key block is not the correct size' |
| 60 | ); |
| 61 | } |
| 62 | $this->key = $key; |
| 63 | $this->initialized = true; |
| 64 | } |
| 65 | |
| 66 | /** |
| 67 | * Decrypt a block of data using the supplied string key |
| 68 | * |
| 69 | * Note that the supplied data should be the same size as the block size of |
| 70 | * the cipher being used. |
| 71 | * |
| 72 | * @param string $data The data to decrypt |
| 73 | * |
| 74 | * @return string The result decrypted data |
| 75 | */ |
| 76 | protected function decryptBlockData($data) { |
| 77 | $key = $this->key; |
| 78 | $this->key = substr($key, 16, 8); |
| 79 | $this->initialize(); |
| 80 | $data = parent::decryptBlockData($data); |
| 81 | $this->key = substr($key, 8, 8); |
| 82 | $this->initialize(); |
| 83 | $data = parent::encryptBlockData($data); |
| 84 | $this->key = substr($key, 0, 8); |
| 85 | $this->initialize(); |
| 86 | $data = parent::decryptBlockData($data); |
| 87 | $this->key = $key; |
| 88 | return $data; |
| 89 | } |
| 90 | |
| 91 | /** |
| 92 | * Encrypt a block of data using the supplied string key |
| 93 | * |
| 94 | * Note that the supplied data should be the same size as the block size of |
| 95 | * the cipher being used. |
| 96 | * |
| 97 | * @param string $data The data to encrypt |
| 98 | * |
| 99 | * @return string The result encrypted data |
| 100 | */ |
| 101 | protected function encryptBlockData($data) { |
| 102 | $key = $this->key; |
| 103 | $this->key = substr($key, 0, 8); |
| 104 | $this->initialize(); |
| 105 | $data = parent::encryptBlockData($data); |
| 106 | $this->key = substr($key, 8, 8); |
| 107 | $this->initialize(); |
| 108 | $data = parent::decryptBlockData($data); |
| 109 | $this->key = substr($key, 16, 8); |
| 110 | $this->initialize(); |
| 111 | $data = parent::encryptBlockData($data); |
| 112 | $this->key = $key; |
| 113 | return $data; |
| 114 | } |
| 115 | |
| 116 | } |