diff options
author | Evan Prodromou <evan@status.net> | 2010-03-17 09:38:39 -0500 |
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committer | Evan Prodromou <evan@status.net> | 2010-03-17 09:38:39 -0500 |
commit | 4761c07ad8d76f7c34d4db53d32d15e806ba1e88 (patch) | |
tree | eb3d78ccde1778037165c92b6ec36c7465b54345 /plugins/OStatus/extlib/Crypt/AES.php | |
parent | f21f78364a9cbde2ca535a3983b384707ad097ae (diff) | |
parent | f62b8a80cf33ac8529d0736c51dc060a9d235369 (diff) |
Merge branch 'testing' of git@gitorious.org:statusnet/mainline into testing
Diffstat (limited to 'plugins/OStatus/extlib/Crypt/AES.php')
-rw-r--r-- | plugins/OStatus/extlib/Crypt/AES.php | 479 |
1 files changed, 479 insertions, 0 deletions
diff --git a/plugins/OStatus/extlib/Crypt/AES.php b/plugins/OStatus/extlib/Crypt/AES.php new file mode 100644 index 000000000..68ab4db09 --- /dev/null +++ b/plugins/OStatus/extlib/Crypt/AES.php @@ -0,0 +1,479 @@ +<?php +/* vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4: */ + +/** + * Pure-PHP implementation of AES. + * + * Uses mcrypt, if available, and an internal implementation, otherwise. + * + * PHP versions 4 and 5 + * + * If {@link Crypt_AES::setKeyLength() setKeyLength()} isn't called, it'll be calculated from + * {@link Crypt_AES::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 160-bits and 160 bits will be the key length until {@link Crypt_Rijndael::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 Crypt_AES::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: This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + * + * @category Crypt + * @package Crypt_AES + * @author Jim Wigginton <terrafrost@php.net> + * @copyright MMVIII Jim Wigginton + * @license http://www.gnu.org/licenses/lgpl.txt + * @version $Id: AES.php,v 1.7 2010/02/09 06:10:25 terrafrost Exp $ + * @link http://phpseclib.sourceforge.net + */ + +/** + * Include Crypt_Rijndael + */ +require_once 'Rijndael.php'; + +/**#@+ + * @access public + * @see Crypt_AES::encrypt() + * @see Crypt_AES::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', -1); +/** + * 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', 1); +/** + * 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', 2); +/**#@-*/ + +/**#@+ + * @access private + * @see Crypt_AES::Crypt_AES() + */ +/** + * Toggles the internal implementation + */ +define('CRYPT_AES_MODE_INTERNAL', 1); +/** + * Toggles the mcrypt implementation + */ +define('CRYPT_AES_MODE_MCRYPT', 2); +/**#@-*/ + +/** + * Pure-PHP implementation of AES. + * + * @author Jim Wigginton <terrafrost@php.net> + * @version 0.1.0 + * @access public + * @package Crypt_AES + */ +class Crypt_AES extends Crypt_Rijndael { + /** + * mcrypt resource for encryption + * + * The mcrypt resource can be recreated every time something needs to be created or it can be created just once. + * Since mcrypt operates in continuous mode, by default, it'll need to be recreated when in non-continuous mode. + * + * @see Crypt_AES::encrypt() + * @var String + * @access private + */ + var $enmcrypt; + + /** + * mcrypt resource for decryption + * + * The mcrypt resource can be recreated every time something needs to be created or it can be created just once. + * Since mcrypt operates in continuous mode, by default, it'll need to be recreated when in non-continuous mode. + * + * @see Crypt_AES::decrypt() + * @var String + * @access private + */ + var $demcrypt; + + /** + * Default Constructor. + * + * Determines whether or not the mcrypt extension should be used. $mode should only, at present, be + * CRYPT_AES_MODE_ECB or CRYPT_AES_MODE_CBC. If not explictly set, CRYPT_AES_MODE_CBC will be used. + * + * @param optional Integer $mode + * @return Crypt_AES + * @access public + */ + function Crypt_AES($mode = CRYPT_AES_MODE_CBC) + { + if ( !defined('CRYPT_AES_MODE') ) { + switch (true) { + case extension_loaded('mcrypt'): + // i'd check to see if aes was supported, by doing in_array('des', mcrypt_list_algorithms('')), + // but since that can be changed after the object has been created, there doesn't seem to be + // a lot of point... + define('CRYPT_AES_MODE', CRYPT_AES_MODE_MCRYPT); + break; + default: + define('CRYPT_AES_MODE', CRYPT_AES_MODE_INTERNAL); + } + } + + switch ( CRYPT_AES_MODE ) { + case CRYPT_AES_MODE_MCRYPT: + switch ($mode) { + case CRYPT_AES_MODE_ECB: + $this->mode = MCRYPT_MODE_ECB; + break; + case CRYPT_AES_MODE_CTR: + // ctr doesn't have a constant associated with it even though it appears to be fairly widely + // supported. in lieu of knowing just how widely supported it is, i've, for now, opted not to + // include a compatibility layer. the layer has been implemented but, for now, is commented out. + $this->mode = 'ctr'; + //$this->mode = in_array('ctr', mcrypt_list_modes()) ? 'ctr' : CRYPT_AES_MODE_CTR; + break; + case CRYPT_AES_MODE_CBC: + default: + $this->mode = MCRYPT_MODE_CBC; + } + + break; + default: + switch ($mode) { + case CRYPT_AES_MODE_ECB: + $this->mode = CRYPT_RIJNDAEL_MODE_ECB; + break; + case CRYPT_AES_MODE_CTR: + $this->mode = CRYPT_RIJNDAEL_MODE_CTR; + break; + case CRYPT_AES_MODE_CBC: + default: + $this->mode = CRYPT_RIJNDAEL_MODE_CBC; + } + } + + if (CRYPT_AES_MODE == CRYPT_AES_MODE_INTERNAL) { + parent::Crypt_Rijndael($this->mode); + } + } + + /** + * Dummy function + * + * Since Crypt_AES extends Crypt_Rijndael, this function is, technically, available, but it doesn't do anything. + * + * @access public + * @param Integer $length + */ + function setBlockLength($length) + { + return; + } + + /** + * Encrypts a message. + * + * $plaintext will be padded with up to 16 additional bytes. Other AES implementations may or may not pad in the + * same manner. Other common approaches to padding and the reasons why it's necessary are discussed in the following + * URL: + * + * {@link http://www.di-mgt.com.au/cryptopad.html http://www.di-mgt.com.au/cryptopad.html} + * + * An alternative to padding is to, separately, send the length of the file. This is what SSH, in fact, does. + * strlen($plaintext) will still need to be a multiple of 16, however, arbitrary values can be added to make it that + * length. + * + * @see Crypt_AES::decrypt() + * @access public + * @param String $plaintext + */ + function encrypt($plaintext) + { + if ( CRYPT_AES_MODE == CRYPT_AES_MODE_MCRYPT ) { + $this->_mcryptSetup(); + /* + if ($this->mode == CRYPT_AES_MODE_CTR) { + $iv = $this->encryptIV; + $xor = mcrypt_generic($this->enmcrypt, $this->_generate_xor(strlen($plaintext), $iv)); + $ciphertext = $plaintext ^ $xor; + if ($this->continuousBuffer) { + $this->encryptIV = $iv; + } + return $ciphertext; + } + */ + + if ($this->mode != 'ctr') { + $plaintext = $this->_pad($plaintext); + } + + $ciphertext = mcrypt_generic($this->enmcrypt, $plaintext); + + if (!$this->continuousBuffer) { + mcrypt_generic_init($this->enmcrypt, $this->key, $this->iv); + } + + return $ciphertext; + } + + return parent::encrypt($plaintext); + } + + /** + * Decrypts a message. + * + * If strlen($ciphertext) is not a multiple of 16, null bytes will be added to the end of the string until it is. + * + * @see Crypt_AES::encrypt() + * @access public + * @param String $ciphertext + */ + function decrypt($ciphertext) + { + if ( CRYPT_AES_MODE == CRYPT_AES_MODE_MCRYPT ) { + $this->_mcryptSetup(); + /* + if ($this->mode == CRYPT_AES_MODE_CTR) { + $iv = $this->decryptIV; + $xor = mcrypt_generic($this->enmcrypt, $this->_generate_xor(strlen($ciphertext), $iv)); + $plaintext = $ciphertext ^ $xor; + if ($this->continuousBuffer) { + $this->decryptIV = $iv; + } + return $plaintext; + } + */ + + if ($this->mode != 'ctr') { + // we pad with chr(0) since that's what mcrypt_generic does. to quote from http://php.net/function.mcrypt-generic : + // "The data is padded with "\0" to make sure the length of the data is n * blocksize." + $ciphertext = str_pad($ciphertext, (strlen($ciphertext) + 15) & 0xFFFFFFF0, chr(0)); + } + + $plaintext = mdecrypt_generic($this->demcrypt, $ciphertext); + + if (!$this->continuousBuffer) { + mcrypt_generic_init($this->demcrypt, $this->key, $this->iv); + } + + return $this->mode != 'ctr' ? $this->_unpad($plaintext) : $plaintext; + } + + return parent::decrypt($ciphertext); + } + + /** + * Setup mcrypt + * + * Validates all the variables. + * + * @access private + */ + function _mcryptSetup() + { + if (!$this->changed) { + return; + } + + if (!$this->explicit_key_length) { + // this just copied from Crypt_Rijndael::_setup() + $length = strlen($this->key) >> 2; + if ($length > 8) { + $length = 8; + } else if ($length < 4) { + $length = 4; + } + $this->Nk = $length; + $this->key_size = $length << 2; + } + + switch ($this->Nk) { + case 4: // 128 + $this->key_size = 16; + break; + case 5: // 160 + case 6: // 192 + $this->key_size = 24; + break; + case 7: // 224 + case 8: // 256 + $this->key_size = 32; + } + + $this->key = substr($this->key, 0, $this->key_size); + $this->encryptIV = $this->decryptIV = $this->iv = str_pad(substr($this->iv, 0, 16), 16, chr(0)); + + if (!isset($this->enmcrypt)) { + $mode = $this->mode; + //$mode = $this->mode == CRYPT_AES_MODE_CTR ? MCRYPT_MODE_ECB : $this->mode; + + $this->demcrypt = mcrypt_module_open(MCRYPT_RIJNDAEL_128, '', $mode, ''); + $this->enmcrypt = mcrypt_module_open(MCRYPT_RIJNDAEL_128, '', $mode, ''); + } // else should mcrypt_generic_deinit be called? + + mcrypt_generic_init($this->demcrypt, $this->key, $this->iv); + mcrypt_generic_init($this->enmcrypt, $this->key, $this->iv); + + $this->changed = false; + } + + /** + * Encrypts a block + * + * Optimized over Crypt_Rijndael's implementation by means of loop unrolling. + * + * @see Crypt_Rijndael::_encryptBlock() + * @access private + * @param String $in + * @return String + */ + function _encryptBlock($in) + { + $state = unpack('N*word', $in); + + $Nr = $this->Nr; + $w = $this->w; + $t0 = $this->t0; + $t1 = $this->t1; + $t2 = $this->t2; + $t3 = $this->t3; + + // addRoundKey and reindex $state + $state = array( + $state['word1'] ^ $w[0][0], + $state['word2'] ^ $w[0][1], + $state['word3'] ^ $w[0][2], + $state['word4'] ^ $w[0][3] + ); + + // shiftRows + subWord + mixColumns + addRoundKey + // we could loop unroll this and use if statements to do more rounds as necessary, but, in my tests, that yields + // only a marginal improvement. since that also, imho, hinders the readability of the code, i've opted not to do it. + for ($round = 1; $round < $this->Nr; $round++) { + $state = array( + $t0[$state[0] & 0xFF000000] ^ $t1[$state[1] & 0x00FF0000] ^ $t2[$state[2] & 0x0000FF00] ^ $t3[$state[3] & 0x000000FF] ^ $w[$round][0], + $t0[$state[1] & 0xFF000000] ^ $t1[$state[2] & 0x00FF0000] ^ $t2[$state[3] & 0x0000FF00] ^ $t3[$state[0] & 0x000000FF] ^ $w[$round][1], + $t0[$state[2] & 0xFF000000] ^ $t1[$state[3] & 0x00FF0000] ^ $t2[$state[0] & 0x0000FF00] ^ $t3[$state[1] & 0x000000FF] ^ $w[$round][2], + $t0[$state[3] & 0xFF000000] ^ $t1[$state[0] & 0x00FF0000] ^ $t2[$state[1] & 0x0000FF00] ^ $t3[$state[2] & 0x000000FF] ^ $w[$round][3] + ); + + } + + // subWord + $state = array( + $this->_subWord($state[0]), + $this->_subWord($state[1]), + $this->_subWord($state[2]), + $this->_subWord($state[3]) + ); + + // shiftRows + addRoundKey + $state = array( + ($state[0] & 0xFF000000) ^ ($state[1] & 0x00FF0000) ^ ($state[2] & 0x0000FF00) ^ ($state[3] & 0x000000FF) ^ $this->w[$this->Nr][0], + ($state[1] & 0xFF000000) ^ ($state[2] & 0x00FF0000) ^ ($state[3] & 0x0000FF00) ^ ($state[0] & 0x000000FF) ^ $this->w[$this->Nr][1], + ($state[2] & 0xFF000000) ^ ($state[3] & 0x00FF0000) ^ ($state[0] & 0x0000FF00) ^ ($state[1] & 0x000000FF) ^ $this->w[$this->Nr][2], + ($state[3] & 0xFF000000) ^ ($state[0] & 0x00FF0000) ^ ($state[1] & 0x0000FF00) ^ ($state[2] & 0x000000FF) ^ $this->w[$this->Nr][3] + ); + + return pack('N*', $state[0], $state[1], $state[2], $state[3]); + } + + /** + * Decrypts a block + * + * Optimized over Crypt_Rijndael's implementation by means of loop unrolling. + * + * @see Crypt_Rijndael::_decryptBlock() + * @access private + * @param String $in + * @return String + */ + function _decryptBlock($in) + { + $state = unpack('N*word', $in); + + $Nr = $this->Nr; + $dw = $this->dw; + $dt0 = $this->dt0; + $dt1 = $this->dt1; + $dt2 = $this->dt2; + $dt3 = $this->dt3; + + // addRoundKey and reindex $state + $state = array( + $state['word1'] ^ $dw[$this->Nr][0], + $state['word2'] ^ $dw[$this->Nr][1], + $state['word3'] ^ $dw[$this->Nr][2], + $state['word4'] ^ $dw[$this->Nr][3] + ); + + + // invShiftRows + invSubBytes + invMixColumns + addRoundKey + for ($round = $this->Nr - 1; $round > 0; $round--) { + $state = array( + $dt0[$state[0] & 0xFF000000] ^ $dt1[$state[3] & 0x00FF0000] ^ $dt2[$state[2] & 0x0000FF00] ^ $dt3[$state[1] & 0x000000FF] ^ $dw[$round][0], + $dt0[$state[1] & 0xFF000000] ^ $dt1[$state[0] & 0x00FF0000] ^ $dt2[$state[3] & 0x0000FF00] ^ $dt3[$state[2] & 0x000000FF] ^ $dw[$round][1], + $dt0[$state[2] & 0xFF000000] ^ $dt1[$state[1] & 0x00FF0000] ^ $dt2[$state[0] & 0x0000FF00] ^ $dt3[$state[3] & 0x000000FF] ^ $dw[$round][2], + $dt0[$state[3] & 0xFF000000] ^ $dt1[$state[2] & 0x00FF0000] ^ $dt2[$state[1] & 0x0000FF00] ^ $dt3[$state[0] & 0x000000FF] ^ $dw[$round][3] + ); + } + + // invShiftRows + invSubWord + addRoundKey + $state = array( + $this->_invSubWord(($state[0] & 0xFF000000) ^ ($state[3] & 0x00FF0000) ^ ($state[2] & 0x0000FF00) ^ ($state[1] & 0x000000FF)) ^ $dw[0][0], + $this->_invSubWord(($state[1] & 0xFF000000) ^ ($state[0] & 0x00FF0000) ^ ($state[3] & 0x0000FF00) ^ ($state[2] & 0x000000FF)) ^ $dw[0][1], + $this->_invSubWord(($state[2] & 0xFF000000) ^ ($state[1] & 0x00FF0000) ^ ($state[0] & 0x0000FF00) ^ ($state[3] & 0x000000FF)) ^ $dw[0][2], + $this->_invSubWord(($state[3] & 0xFF000000) ^ ($state[2] & 0x00FF0000) ^ ($state[1] & 0x0000FF00) ^ ($state[0] & 0x000000FF)) ^ $dw[0][3] + ); + + return pack('N*', $state[0], $state[1], $state[2], $state[3]); + } +} + +// vim: ts=4:sw=4:et: +// vim6: fdl=1:
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