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/DES.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/DES.php')
-rw-r--r-- | plugins/OStatus/extlib/Crypt/DES.php | 945 |
1 files changed, 945 insertions, 0 deletions
diff --git a/plugins/OStatus/extlib/Crypt/DES.php b/plugins/OStatus/extlib/Crypt/DES.php new file mode 100644 index 000000000..985ed25b5 --- /dev/null +++ b/plugins/OStatus/extlib/Crypt/DES.php @@ -0,0 +1,945 @@ +<?php +/* vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4: */ + +/** + * Pure-PHP implementation of DES. + * + * Uses mcrypt, if available, and an internal implementation, otherwise. + * + * PHP versions 4 and 5 + * + * Useful resources are as follows: + * + * - {@link http://en.wikipedia.org/wiki/DES_supplementary_material Wikipedia: DES supplementary material} + * - {@link http://www.itl.nist.gov/fipspubs/fip46-2.htm FIPS 46-2 - (DES), Data Encryption Standard} + * - {@link http://www.cs.eku.edu/faculty/styer/460/Encrypt/JS-DES.html JavaScript DES Example} + * + * Here's a short example of how to use this library: + * <code> + * <?php + * include('Crypt/DES.php'); + * + * $des = new Crypt_DES(); + * + * $des->setKey('abcdefgh'); + * + * $size = 10 * 1024; + * $plaintext = ''; + * for ($i = 0; $i < $size; $i++) { + * $plaintext.= 'a'; + * } + * + * echo $des->decrypt($des->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_DES + * @author Jim Wigginton <terrafrost@php.net> + * @copyright MMVII Jim Wigginton + * @license http://www.gnu.org/licenses/lgpl.txt + * @version $Id: DES.php,v 1.12 2010/02/09 06:10:26 terrafrost Exp $ + * @link http://phpseclib.sourceforge.net + */ + +/**#@+ + * @access private + * @see Crypt_DES::_prepareKey() + * @see Crypt_DES::_processBlock() + */ +/** + * Contains array_reverse($keys[CRYPT_DES_DECRYPT]) + */ +define('CRYPT_DES_ENCRYPT', 0); +/** + * Contains array_reverse($keys[CRYPT_DES_ENCRYPT]) + */ +define('CRYPT_DES_DECRYPT', 1); +/**#@-*/ + +/**#@+ + * @access public + * @see Crypt_DES::encrypt() + * @see Crypt_DES::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_DES_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_DES_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_DES_MODE_CBC', 2); +/**#@-*/ + +/**#@+ + * @access private + * @see Crypt_DES::Crypt_DES() + */ +/** + * Toggles the internal implementation + */ +define('CRYPT_DES_MODE_INTERNAL', 1); +/** + * Toggles the mcrypt implementation + */ +define('CRYPT_DES_MODE_MCRYPT', 2); +/**#@-*/ + +/** + * Pure-PHP implementation of DES. + * + * @author Jim Wigginton <terrafrost@php.net> + * @version 0.1.0 + * @access public + * @package Crypt_DES + */ +class Crypt_DES { + /** + * The Key Schedule + * + * @see Crypt_DES::setKey() + * @var Array + * @access private + */ + var $keys = "\0\0\0\0\0\0\0\0"; + + /** + * The Encryption Mode + * + * @see Crypt_DES::Crypt_DES() + * @var Integer + * @access private + */ + var $mode; + + /** + * Continuous Buffer status + * + * @see Crypt_DES::enableContinuousBuffer() + * @var Boolean + * @access private + */ + var $continuousBuffer = false; + + /** + * Padding status + * + * @see Crypt_DES::enablePadding() + * @var Boolean + * @access private + */ + var $padding = true; + + /** + * The Initialization Vector + * + * @see Crypt_DES::setIV() + * @var String + * @access private + */ + var $iv = "\0\0\0\0\0\0\0\0"; + + /** + * A "sliding" Initialization Vector + * + * @see Crypt_DES::enableContinuousBuffer() + * @var String + * @access private + */ + var $encryptIV = "\0\0\0\0\0\0\0\0"; + + /** + * A "sliding" Initialization Vector + * + * @see Crypt_DES::enableContinuousBuffer() + * @var String + * @access private + */ + var $decryptIV = "\0\0\0\0\0\0\0\0"; + + /** + * 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; + + /** + * Does the (en|de)mcrypt resource need to be (re)initialized? + * + * @see setKey() + * @see setIV() + * @var Boolean + * @access private + */ + var $changed = true; + + /** + * Default Constructor. + * + * Determines whether or not the mcrypt extension should be used. $mode should only, at present, be + * CRYPT_DES_MODE_ECB or CRYPT_DES_MODE_CBC. If not explictly set, CRYPT_DES_MODE_CBC will be used. + * + * @param optional Integer $mode + * @return Crypt_DES + * @access public + */ + function Crypt_DES($mode = CRYPT_MODE_DES_CBC) + { + if ( !defined('CRYPT_DES_MODE') ) { + switch (true) { + case extension_loaded('mcrypt'): + // i'd check to see if des 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_DES_MODE', CRYPT_DES_MODE_MCRYPT); + break; + default: + define('CRYPT_DES_MODE', CRYPT_DES_MODE_INTERNAL); + } + } + + switch ( CRYPT_DES_MODE ) { + case CRYPT_DES_MODE_MCRYPT: + switch ($mode) { + case CRYPT_DES_MODE_ECB: + $this->mode = MCRYPT_MODE_ECB; + break; + case CRYPT_DES_MODE_CTR: + $this->mode = 'ctr'; + //$this->mode = in_array('ctr', mcrypt_list_modes()) ? 'ctr' : CRYPT_DES_MODE_CTR; + break; + case CRYPT_DES_MODE_CBC: + default: + $this->mode = MCRYPT_MODE_CBC; + } + + break; + default: + switch ($mode) { + case CRYPT_DES_MODE_ECB: + case CRYPT_DES_MODE_CTR: + case CRYPT_DES_MODE_CBC: + $this->mode = $mode; + break; + default: + $this->mode = CRYPT_DES_MODE_CBC; + } + } + } + + /** + * Sets the key. + * + * Keys can be of any length. DES, itself, uses 64-bit keys (eg. strlen($key) == 8), however, we + * only use the first eight, if $key has more then eight characters in it, and pad $key with the + * null byte if it is less then eight characters long. + * + * DES also requires that every eighth bit be a parity bit, however, we'll ignore that. + * + * If the key is not explicitly set, it'll be assumed to be all zero's. + * + * @access public + * @param String $key + */ + function setKey($key) + { + $this->keys = ( CRYPT_DES_MODE == CRYPT_DES_MODE_MCRYPT ) ? substr($key, 0, 8) : $this->_prepareKey($key); + $this->changed = true; + } + + /** + * Sets the initialization vector. (optional) + * + * SetIV is not required when CRYPT_DES_MODE_ECB is being used. If not explictly set, it'll be assumed + * to be all zero's. + * + * @access public + * @param String $iv + */ + function setIV($iv) + { + $this->encryptIV = $this->decryptIV = $this->iv = str_pad(substr($iv, 0, 8), 8, chr(0)); + $this->changed = true; + } + + /** + * Generate CTR XOR encryption key + * + * Encrypt the output of this and XOR it against the ciphertext / plaintext to get the + * plaintext / ciphertext in CTR mode. + * + * @see Crypt_DES::decrypt() + * @see Crypt_DES::encrypt() + * @access public + * @param Integer $length + * @param String $iv + */ + function _generate_xor($length, &$iv) + { + $xor = ''; + $num_blocks = ($length + 7) >> 3; + for ($i = 0; $i < $num_blocks; $i++) { + $xor.= $iv; + for ($j = 4; $j <= 8; $j+=4) { + $temp = substr($iv, -$j, 4); + switch ($temp) { + case "\xFF\xFF\xFF\xFF": + $iv = substr_replace($iv, "\x00\x00\x00\x00", -$j, 4); + break; + case "\x7F\xFF\xFF\xFF": + $iv = substr_replace($iv, "\x80\x00\x00\x00", -$j, 4); + break 2; + default: + extract(unpack('Ncount', $temp)); + $iv = substr_replace($iv, pack('N', $count + 1), -$j, 4); + break 2; + } + } + } + + return $xor; + } + + /** + * Encrypts a message. + * + * $plaintext will be padded with up to 8 additional bytes. Other DES implementations may or may not pad in the + * same manner. Other common approaches to padding and the reasons why it's necessary are discussed in the following + * URL: + * + * {@link http://www.di-mgt.com.au/cryptopad.html http://www.di-mgt.com.au/cryptopad.html} + * + * An alternative to padding is to, separately, send the length of the file. This is what SSH, in fact, does. + * strlen($plaintext) will still need to be a multiple of 8, however, arbitrary values can be added to make it that + * length. + * + * @see Crypt_DES::decrypt() + * @access public + * @param String $plaintext + */ + function encrypt($plaintext) + { + if ($this->mode != CRYPT_DES_MODE_CTR && $this->mode != 'ctr') { + $plaintext = $this->_pad($plaintext); + } + + if ( CRYPT_DES_MODE == CRYPT_DES_MODE_MCRYPT ) { + if ($this->changed) { + if (!isset($this->enmcrypt)) { + $this->enmcrypt = mcrypt_module_open(MCRYPT_DES, '', $this->mode, ''); + } + mcrypt_generic_init($this->enmcrypt, $this->keys, $this->encryptIV); + $this->changed = false; + } + + $ciphertext = mcrypt_generic($this->enmcrypt, $plaintext); + + if (!$this->continuousBuffer) { + mcrypt_generic_init($this->enmcrypt, $this->keys, $this->encryptIV); + } + + return $ciphertext; + } + + if (!is_array($this->keys)) { + $this->keys = $this->_prepareKey("\0\0\0\0\0\0\0\0"); + } + + $ciphertext = ''; + switch ($this->mode) { + case CRYPT_DES_MODE_ECB: + for ($i = 0; $i < strlen($plaintext); $i+=8) { + $ciphertext.= $this->_processBlock(substr($plaintext, $i, 8), CRYPT_DES_ENCRYPT); + } + break; + case CRYPT_DES_MODE_CBC: + $xor = $this->encryptIV; + for ($i = 0; $i < strlen($plaintext); $i+=8) { + $block = substr($plaintext, $i, 8); + $block = $this->_processBlock($block ^ $xor, CRYPT_DES_ENCRYPT); + $xor = $block; + $ciphertext.= $block; + } + if ($this->continuousBuffer) { + $this->encryptIV = $xor; + } + break; + case CRYPT_DES_MODE_CTR: + $xor = $this->encryptIV; + for ($i = 0; $i < strlen($plaintext); $i+=8) { + $block = substr($plaintext, $i, 8); + $key = $this->_processBlock($this->_generate_xor(8, $xor), CRYPT_DES_ENCRYPT); + $ciphertext.= $block ^ $key; + } + if ($this->continuousBuffer) { + $this->encryptIV = $xor; + } + } + + return $ciphertext; + } + + /** + * Decrypts a message. + * + * If strlen($ciphertext) is not a multiple of 8, null bytes will be added to the end of the string until it is. + * + * @see Crypt_DES::encrypt() + * @access public + * @param String $ciphertext + */ + function decrypt($ciphertext) + { + if ($this->mode != CRYPT_DES_MODE_CTR && $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($ciphertext) + 7) & 0xFFFFFFF8, chr(0)); + } + + if ( CRYPT_DES_MODE == CRYPT_DES_MODE_MCRYPT ) { + if ($this->changed) { + if (!isset($this->demcrypt)) { + $this->demcrypt = mcrypt_module_open(MCRYPT_DES, '', $this->mode, ''); + } + mcrypt_generic_init($this->demcrypt, $this->keys, $this->decryptIV); + $this->changed = false; + } + + $plaintext = mdecrypt_generic($this->demcrypt, $ciphertext); + + if (!$this->continuousBuffer) { + mcrypt_generic_init($this->demcrypt, $this->keys, $this->decryptIV); + } + + return $this->mode != 'ctr' ? $this->_unpad($plaintext) : $plaintext; + } + + if (!is_array($this->keys)) { + $this->keys = $this->_prepareKey("\0\0\0\0\0\0\0\0"); + } + + $plaintext = ''; + switch ($this->mode) { + case CRYPT_DES_MODE_ECB: + for ($i = 0; $i < strlen($ciphertext); $i+=8) { + $plaintext.= $this->_processBlock(substr($ciphertext, $i, 8), CRYPT_DES_DECRYPT); + } + break; + case CRYPT_DES_MODE_CBC: + $xor = $this->decryptIV; + for ($i = 0; $i < strlen($ciphertext); $i+=8) { + $block = substr($ciphertext, $i, 8); + $plaintext.= $this->_processBlock($block, CRYPT_DES_DECRYPT) ^ $xor; + $xor = $block; + } + if ($this->continuousBuffer) { + $this->decryptIV = $xor; + } + break; + case CRYPT_DES_MODE_CTR: + $xor = $this->decryptIV; + for ($i = 0; $i < strlen($ciphertext); $i+=8) { + $block = substr($ciphertext, $i, 8); + $key = $this->_processBlock($this->_generate_xor(8, $xor), CRYPT_DES_ENCRYPT); + $plaintext.= $block ^ $key; + } + if ($this->continuousBuffer) { + $this->decryptIV = $xor; + } + } + + return $this->mode != CRYPT_DES_MODE_CTR ? $this->_unpad($plaintext) : $plaintext; + } + + /** + * Treat consecutive "packets" as if they are a continuous buffer. + * + * Say you have a 16-byte plaintext $plaintext. Using the default behavior, the two following code snippets + * will yield different outputs: + * + * <code> + * echo $des->encrypt(substr($plaintext, 0, 8)); + * echo $des->encrypt(substr($plaintext, 8, 8)); + * </code> + * <code> + * echo $des->encrypt($plaintext); + * </code> + * + * The solution is to enable the continuous buffer. Although this will resolve the above discrepancy, it creates + * another, as demonstrated with the following: + * + * <code> + * $des->encrypt(substr($plaintext, 0, 8)); + * echo $des->decrypt($des->encrypt(substr($plaintext, 8, 8))); + * </code> + * <code> + * echo $des->decrypt($des->encrypt(substr($plaintext, 8, 8))); + * </code> + * + * With the continuous buffer disabled, these would yield the same output. With it enabled, they yield different + * outputs. The reason is due to the fact that the initialization vector's change after every encryption / + * decryption round when the continuous buffer is enabled. When it's disabled, they remain constant. + * + * Put another way, when the continuous buffer is enabled, the state of the Crypt_DES() object changes after each + * encryption / decryption round, whereas otherwise, it'd remain constant. For this reason, it's recommended that + * continuous buffers not be used. They do offer better security and are, in fact, sometimes required (SSH uses them), + * however, they are also less intuitive and more likely to cause you problems. + * + * @see Crypt_DES::disableContinuousBuffer() + * @access public + */ + function enableContinuousBuffer() + { + $this->continuousBuffer = true; + } + + /** + * Treat consecutive packets as if they are a discontinuous buffer. + * + * The default behavior. + * + * @see Crypt_DES::enableContinuousBuffer() + * @access public + */ + function disableContinuousBuffer() + { + $this->continuousBuffer = false; + $this->encryptIV = $this->iv; + $this->decryptIV = $this->iv; + } + + /** + * Pad "packets". + * + * DES works by encrypting eight bytes at a time. If you ever need to encrypt or decrypt something that's not + * a multiple of eight, it becomes necessary to pad the input so that it's length is a multiple of eight. + * + * Padding is enabled by default. Sometimes, however, it is undesirable to pad strings. Such is the case in SSH1, + * where "packets" are padded with random bytes before being encrypted. Unpad these packets and you risk stripping + * away characters that shouldn't be stripped away. (SSH knows how many bytes are added because the length is + * transmitted separately) + * + * @see Crypt_DES::disablePadding() + * @access public + */ + function enablePadding() + { + $this->padding = true; + } + + /** + * Do not pad packets. + * + * @see Crypt_DES::enablePadding() + * @access public + */ + function disablePadding() + { + $this->padding = false; + } + + /** + * Pads a string + * + * Pads a string using the RSA PKCS padding standards so that its length is a multiple of the blocksize (8). + * 8 - (strlen($text) & 7) bytes are added, each of which is equal to chr(8 - (strlen($text) & 7) + * + * If padding is disabled and $text is not a multiple of the blocksize, the string will be padded regardless + * and padding will, hence forth, be enabled. + * + * @see Crypt_DES::_unpad() + * @access private + */ + function _pad($text) + { + $length = strlen($text); + + if (!$this->padding) { + if (($length & 7) == 0) { + return $text; + } else { + user_error("The plaintext's length ($length) is not a multiple of the block size (8)", E_USER_NOTICE); + $this->padding = true; + } + } + + $pad = 8 - ($length & 7); + return str_pad($text, $length + $pad, chr($pad)); + } + + /** + * Unpads a string + * + * If padding is enabled and the reported padding length is invalid the encryption key will be assumed to be wrong + * and false will be returned. + * + * @see Crypt_DES::_pad() + * @access private + */ + function _unpad($text) + { + if (!$this->padding) { + return $text; + } + + $length = ord($text[strlen($text) - 1]); + + if (!$length || $length > 8) { + return false; + } + + return substr($text, 0, -$length); + } + + /** + * Encrypts or decrypts a 64-bit block + * + * $mode should be either CRYPT_DES_ENCRYPT or CRYPT_DES_DECRYPT. See + * {@link http://en.wikipedia.org/wiki/Image:Feistel.png Feistel.png} to get a general + * idea of what this function does. + * + * @access private + * @param String $block + * @param Integer $mode + * @return String + */ + function _processBlock($block, $mode) + { + // s-boxes. in the official DES docs, they're described as being matrices that + // one accesses by using the first and last bits to determine the row and the + // middle four bits to determine the column. in this implementation, they've + // been converted to vectors + static $sbox = array( + array( + 14, 0, 4, 15, 13, 7, 1, 4, 2, 14, 15, 2, 11, 13, 8, 1, + 3, 10 ,10, 6, 6, 12, 12, 11, 5, 9, 9, 5, 0, 3, 7, 8, + 4, 15, 1, 12, 14, 8, 8, 2, 13, 4, 6, 9, 2, 1, 11, 7, + 15, 5, 12, 11, 9, 3, 7, 14, 3, 10, 10, 0, 5, 6, 0, 13 + ), + array( + 15, 3, 1, 13, 8, 4, 14, 7, 6, 15, 11, 2, 3, 8, 4, 14, + 9, 12, 7, 0, 2, 1, 13, 10, 12, 6, 0, 9, 5, 11, 10, 5, + 0, 13, 14, 8, 7, 10, 11, 1, 10, 3, 4, 15, 13, 4, 1, 2, + 5, 11, 8, 6, 12, 7, 6, 12, 9, 0, 3, 5, 2, 14, 15, 9 + ), + array( + 10, 13, 0, 7, 9, 0, 14, 9, 6, 3, 3, 4, 15, 6, 5, 10, + 1, 2, 13, 8, 12, 5, 7, 14, 11, 12, 4, 11, 2, 15, 8, 1, + 13, 1, 6, 10, 4, 13, 9, 0, 8, 6, 15, 9, 3, 8, 0, 7, + 11, 4, 1, 15, 2, 14, 12, 3, 5, 11, 10, 5, 14, 2, 7, 12 + ), + array( + 7, 13, 13, 8, 14, 11, 3, 5, 0, 6, 6, 15, 9, 0, 10, 3, + 1, 4, 2, 7, 8, 2, 5, 12, 11, 1, 12, 10, 4, 14, 15, 9, + 10, 3, 6, 15, 9, 0, 0, 6, 12, 10, 11, 1, 7, 13, 13, 8, + 15, 9, 1, 4, 3, 5, 14, 11, 5, 12, 2, 7, 8, 2, 4, 14 + ), + array( + 2, 14, 12, 11, 4, 2, 1, 12, 7, 4, 10, 7, 11, 13, 6, 1, + 8, 5, 5, 0, 3, 15, 15, 10, 13, 3, 0, 9, 14, 8, 9, 6, + 4, 11, 2, 8, 1, 12, 11, 7, 10, 1, 13, 14, 7, 2, 8, 13, + 15, 6, 9, 15, 12, 0, 5, 9, 6, 10, 3, 4, 0, 5, 14, 3 + ), + array( + 12, 10, 1, 15, 10, 4, 15, 2, 9, 7, 2, 12, 6, 9, 8, 5, + 0, 6, 13, 1, 3, 13, 4, 14, 14, 0, 7, 11, 5, 3, 11, 8, + 9, 4, 14, 3, 15, 2, 5, 12, 2, 9, 8, 5, 12, 15, 3, 10, + 7, 11, 0, 14, 4, 1, 10, 7, 1, 6, 13, 0, 11, 8, 6, 13 + ), + array( + 4, 13, 11, 0, 2, 11, 14, 7, 15, 4, 0, 9, 8, 1, 13, 10, + 3, 14, 12, 3, 9, 5, 7, 12, 5, 2, 10, 15, 6, 8, 1, 6, + 1, 6, 4, 11, 11, 13, 13, 8, 12, 1, 3, 4, 7, 10, 14, 7, + 10, 9, 15, 5, 6, 0, 8, 15, 0, 14, 5, 2, 9, 3, 2, 12 + ), + array( + 13, 1, 2, 15, 8, 13, 4, 8, 6, 10, 15, 3, 11, 7, 1, 4, + 10, 12, 9, 5, 3, 6, 14, 11, 5, 0, 0, 14, 12, 9, 7, 2, + 7, 2, 11, 1, 4, 14, 1, 7, 9, 4, 12, 10, 14, 8, 2, 13, + 0, 15, 6, 12, 10, 9, 13, 0, 15, 3, 3, 5, 5, 6, 8, 11 + ) + ); + + $keys = $this->keys; + + $temp = unpack('Na/Nb', $block); + $block = array($temp['a'], $temp['b']); + + // because php does arithmetic right shifts, if the most significant bits are set, right + // shifting those into the correct position will add 1's - not 0's. this will intefere + // with the | operation unless a second & is done. so we isolate these bits and left shift + // them into place. we then & each block with 0x7FFFFFFF to prevennt 1's from being added + // for any other shifts. + $msb = array( + ($block[0] >> 31) & 1, + ($block[1] >> 31) & 1 + ); + $block[0] &= 0x7FFFFFFF; + $block[1] &= 0x7FFFFFFF; + + // we isolate the appropriate bit in the appropriate integer and shift as appropriate. in + // some cases, there are going to be multiple bits in the same integer that need to be shifted + // in the same way. we combine those into one shift operation. + $block = array( + (($block[1] & 0x00000040) << 25) | (($block[1] & 0x00004000) << 16) | + (($block[1] & 0x00400001) << 7) | (($block[1] & 0x40000100) >> 2) | + (($block[0] & 0x00000040) << 21) | (($block[0] & 0x00004000) << 12) | + (($block[0] & 0x00400001) << 3) | (($block[0] & 0x40000100) >> 6) | + (($block[1] & 0x00000010) << 19) | (($block[1] & 0x00001000) << 10) | + (($block[1] & 0x00100000) << 1) | (($block[1] & 0x10000000) >> 8) | + (($block[0] & 0x00000010) << 15) | (($block[0] & 0x00001000) << 6) | + (($block[0] & 0x00100000) >> 3) | (($block[0] & 0x10000000) >> 12) | + (($block[1] & 0x00000004) << 13) | (($block[1] & 0x00000400) << 4) | + (($block[1] & 0x00040000) >> 5) | (($block[1] & 0x04000000) >> 14) | + (($block[0] & 0x00000004) << 9) | ( $block[0] & 0x00000400 ) | + (($block[0] & 0x00040000) >> 9) | (($block[0] & 0x04000000) >> 18) | + (($block[1] & 0x00010000) >> 11) | (($block[1] & 0x01000000) >> 20) | + (($block[0] & 0x00010000) >> 15) | (($block[0] & 0x01000000) >> 24) + , + (($block[1] & 0x00000080) << 24) | (($block[1] & 0x00008000) << 15) | + (($block[1] & 0x00800002) << 6) | (($block[0] & 0x00000080) << 20) | + (($block[0] & 0x00008000) << 11) | (($block[0] & 0x00800002) << 2) | + (($block[1] & 0x00000020) << 18) | (($block[1] & 0x00002000) << 9) | + ( $block[1] & 0x00200000 ) | (($block[1] & 0x20000000) >> 9) | + (($block[0] & 0x00000020) << 14) | (($block[0] & 0x00002000) << 5) | + (($block[0] & 0x00200000) >> 4) | (($block[0] & 0x20000000) >> 13) | + (($block[1] & 0x00000008) << 12) | (($block[1] & 0x00000800) << 3) | + (($block[1] & 0x00080000) >> 6) | (($block[1] & 0x08000000) >> 15) | + (($block[0] & 0x00000008) << 8) | (($block[0] & 0x00000800) >> 1) | + (($block[0] & 0x00080000) >> 10) | (($block[0] & 0x08000000) >> 19) | + (($block[1] & 0x00000200) >> 3) | (($block[0] & 0x00000200) >> 7) | + (($block[1] & 0x00020000) >> 12) | (($block[1] & 0x02000000) >> 21) | + (($block[0] & 0x00020000) >> 16) | (($block[0] & 0x02000000) >> 25) | + ($msb[1] << 28) | ($msb[0] << 24) + ); + + for ($i = 0; $i < 16; $i++) { + // start of "the Feistel (F) function" - see the following URL: + // http://en.wikipedia.org/wiki/Image:Data_Encryption_Standard_InfoBox_Diagram.png + $temp = (($sbox[0][((($block[1] >> 27) & 0x1F) | (($block[1] & 1) << 5)) ^ $keys[$mode][$i][0]]) << 28) + | (($sbox[1][(($block[1] & 0x1F800000) >> 23) ^ $keys[$mode][$i][1]]) << 24) + | (($sbox[2][(($block[1] & 0x01F80000) >> 19) ^ $keys[$mode][$i][2]]) << 20) + | (($sbox[3][(($block[1] & 0x001F8000) >> 15) ^ $keys[$mode][$i][3]]) << 16) + | (($sbox[4][(($block[1] & 0x0001F800) >> 11) ^ $keys[$mode][$i][4]]) << 12) + | (($sbox[5][(($block[1] & 0x00001F80) >> 7) ^ $keys[$mode][$i][5]]) << 8) + | (($sbox[6][(($block[1] & 0x000001F8) >> 3) ^ $keys[$mode][$i][6]]) << 4) + | ( $sbox[7][((($block[1] & 0x1F) << 1) | (($block[1] >> 31) & 1)) ^ $keys[$mode][$i][7]]); + + $msb = ($temp >> 31) & 1; + $temp &= 0x7FFFFFFF; + $newBlock = (($temp & 0x00010000) << 15) | (($temp & 0x02020120) << 5) + | (($temp & 0x00001800) << 17) | (($temp & 0x01000000) >> 10) + | (($temp & 0x00000008) << 24) | (($temp & 0x00100000) << 6) + | (($temp & 0x00000010) << 21) | (($temp & 0x00008000) << 9) + | (($temp & 0x00000200) << 12) | (($temp & 0x10000000) >> 27) + | (($temp & 0x00000040) << 14) | (($temp & 0x08000000) >> 8) + | (($temp & 0x00004000) << 4) | (($temp & 0x00000002) << 16) + | (($temp & 0x00442000) >> 6) | (($temp & 0x40800000) >> 15) + | (($temp & 0x00000001) << 11) | (($temp & 0x20000000) >> 20) + | (($temp & 0x00080000) >> 13) | (($temp & 0x00000004) << 3) + | (($temp & 0x04000000) >> 22) | (($temp & 0x00000480) >> 7) + | (($temp & 0x00200000) >> 19) | ($msb << 23); + // end of "the Feistel (F) function" - $newBlock is F's output + + $temp = $block[1]; + $block[1] = $block[0] ^ $newBlock; + $block[0] = $temp; + } + + $msb = array( + ($block[0] >> 31) & 1, + ($block[1] >> 31) & 1 + ); + $block[0] &= 0x7FFFFFFF; + $block[1] &= 0x7FFFFFFF; + + $block = array( + (($block[0] & 0x01000004) << 7) | (($block[1] & 0x01000004) << 6) | + (($block[0] & 0x00010000) << 13) | (($block[1] & 0x00010000) << 12) | + (($block[0] & 0x00000100) << 19) | (($block[1] & 0x00000100) << 18) | + (($block[0] & 0x00000001) << 25) | (($block[1] & 0x00000001) << 24) | + (($block[0] & 0x02000008) >> 2) | (($block[1] & 0x02000008) >> 3) | + (($block[0] & 0x00020000) << 4) | (($block[1] & 0x00020000) << 3) | + (($block[0] & 0x00000200) << 10) | (($block[1] & 0x00000200) << 9) | + (($block[0] & 0x00000002) << 16) | (($block[1] & 0x00000002) << 15) | + (($block[0] & 0x04000000) >> 11) | (($block[1] & 0x04000000) >> 12) | + (($block[0] & 0x00040000) >> 5) | (($block[1] & 0x00040000) >> 6) | + (($block[0] & 0x00000400) << 1) | ( $block[1] & 0x00000400 ) | + (($block[0] & 0x08000000) >> 20) | (($block[1] & 0x08000000) >> 21) | + (($block[0] & 0x00080000) >> 14) | (($block[1] & 0x00080000) >> 15) | + (($block[0] & 0x00000800) >> 8) | (($block[1] & 0x00000800) >> 9) + , + (($block[0] & 0x10000040) << 3) | (($block[1] & 0x10000040) << 2) | + (($block[0] & 0x00100000) << 9) | (($block[1] & 0x00100000) << 8) | + (($block[0] & 0x00001000) << 15) | (($block[1] & 0x00001000) << 14) | + (($block[0] & 0x00000010) << 21) | (($block[1] & 0x00000010) << 20) | + (($block[0] & 0x20000080) >> 6) | (($block[1] & 0x20000080) >> 7) | + ( $block[0] & 0x00200000 ) | (($block[1] & 0x00200000) >> 1) | + (($block[0] & 0x00002000) << 6) | (($block[1] & 0x00002000) << 5) | + (($block[0] & 0x00000020) << 12) | (($block[1] & 0x00000020) << 11) | + (($block[0] & 0x40000000) >> 15) | (($block[1] & 0x40000000) >> 16) | + (($block[0] & 0x00400000) >> 9) | (($block[1] & 0x00400000) >> 10) | + (($block[0] & 0x00004000) >> 3) | (($block[1] & 0x00004000) >> 4) | + (($block[0] & 0x00800000) >> 18) | (($block[1] & 0x00800000) >> 19) | + (($block[0] & 0x00008000) >> 12) | (($block[1] & 0x00008000) >> 13) | + ($msb[0] << 7) | ($msb[1] << 6) + ); + + return pack('NN', $block[0], $block[1]); + } + + /** + * Creates the key schedule. + * + * @access private + * @param String $key + * @return Array + */ + function _prepareKey($key) + { + static $shifts = array( // number of key bits shifted per round + 1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1 + ); + + // pad the key and remove extra characters as appropriate. + $key = str_pad(substr($key, 0, 8), 8, chr(0)); + + $temp = unpack('Na/Nb', $key); + $key = array($temp['a'], $temp['b']); + $msb = array( + ($key[0] >> 31) & 1, + ($key[1] >> 31) & 1 + ); + $key[0] &= 0x7FFFFFFF; + $key[1] &= 0x7FFFFFFF; + + $key = array( + (($key[1] & 0x00000002) << 26) | (($key[1] & 0x00000204) << 17) | + (($key[1] & 0x00020408) << 8) | (($key[1] & 0x02040800) >> 1) | + (($key[0] & 0x00000002) << 22) | (($key[0] & 0x00000204) << 13) | + (($key[0] & 0x00020408) << 4) | (($key[0] & 0x02040800) >> 5) | + (($key[1] & 0x04080000) >> 10) | (($key[0] & 0x04080000) >> 14) | + (($key[1] & 0x08000000) >> 19) | (($key[0] & 0x08000000) >> 23) | + (($key[0] & 0x00000010) >> 1) | (($key[0] & 0x00001000) >> 10) | + (($key[0] & 0x00100000) >> 19) | (($key[0] & 0x10000000) >> 28) + , + (($key[1] & 0x00000080) << 20) | (($key[1] & 0x00008000) << 11) | + (($key[1] & 0x00800000) << 2) | (($key[0] & 0x00000080) << 16) | + (($key[0] & 0x00008000) << 7) | (($key[0] & 0x00800000) >> 2) | + (($key[1] & 0x00000040) << 13) | (($key[1] & 0x00004000) << 4) | + (($key[1] & 0x00400000) >> 5) | (($key[1] & 0x40000000) >> 14) | + (($key[0] & 0x00000040) << 9) | ( $key[0] & 0x00004000 ) | + (($key[0] & 0x00400000) >> 9) | (($key[0] & 0x40000000) >> 18) | + (($key[1] & 0x00000020) << 6) | (($key[1] & 0x00002000) >> 3) | + (($key[1] & 0x00200000) >> 12) | (($key[1] & 0x20000000) >> 21) | + (($key[0] & 0x00000020) << 2) | (($key[0] & 0x00002000) >> 7) | + (($key[0] & 0x00200000) >> 16) | (($key[0] & 0x20000000) >> 25) | + (($key[1] & 0x00000010) >> 1) | (($key[1] & 0x00001000) >> 10) | + (($key[1] & 0x00100000) >> 19) | (($key[1] & 0x10000000) >> 28) | + ($msb[1] << 24) | ($msb[0] << 20) + ); + + $keys = array(); + for ($i = 0; $i < 16; $i++) { + $key[0] <<= $shifts[$i]; + $temp = ($key[0] & 0xF0000000) >> 28; + $key[0] = ($key[0] | $temp) & 0x0FFFFFFF; + + $key[1] <<= $shifts[$i]; + $temp = ($key[1] & 0xF0000000) >> 28; + $key[1] = ($key[1] | $temp) & 0x0FFFFFFF; + + $temp = array( + (($key[1] & 0x00004000) >> 9) | (($key[1] & 0x00000800) >> 7) | + (($key[1] & 0x00020000) >> 14) | (($key[1] & 0x00000010) >> 2) | + (($key[1] & 0x08000000) >> 26) | (($key[1] & 0x00800000) >> 23) + , + (($key[1] & 0x02400000) >> 20) | (($key[1] & 0x00000001) << 4) | + (($key[1] & 0x00002000) >> 10) | (($key[1] & 0x00040000) >> 18) | + (($key[1] & 0x00000080) >> 6) + , + ( $key[1] & 0x00000020 ) | (($key[1] & 0x00000200) >> 5) | + (($key[1] & 0x00010000) >> 13) | (($key[1] & 0x01000000) >> 22) | + (($key[1] & 0x00000004) >> 1) | (($key[1] & 0x00100000) >> 20) + , + (($key[1] & 0x00001000) >> 7) | (($key[1] & 0x00200000) >> 17) | + (($key[1] & 0x00000002) << 2) | (($key[1] & 0x00000100) >> 6) | + (($key[1] & 0x00008000) >> 14) | (($key[1] & 0x04000000) >> 26) + , + (($key[0] & 0x00008000) >> 10) | ( $key[0] & 0x00000010 ) | + (($key[0] & 0x02000000) >> 22) | (($key[0] & 0x00080000) >> 17) | + (($key[0] & 0x00000200) >> 8) | (($key[0] & 0x00000002) >> 1) + , + (($key[0] & 0x04000000) >> 21) | (($key[0] & 0x00010000) >> 12) | + (($key[0] & 0x00000020) >> 2) | (($key[0] & 0x00000800) >> 9) | + (($key[0] & 0x00800000) >> 22) | (($key[0] & 0x00000100) >> 8) + , + (($key[0] & 0x00001000) >> 7) | (($key[0] & 0x00000088) >> 3) | + (($key[0] & 0x00020000) >> 14) | (($key[0] & 0x00000001) << 2) | + (($key[0] & 0x00400000) >> 21) + , + (($key[0] & 0x00000400) >> 5) | (($key[0] & 0x00004000) >> 10) | + (($key[0] & 0x00000040) >> 3) | (($key[0] & 0x00100000) >> 18) | + (($key[0] & 0x08000000) >> 26) | (($key[0] & 0x01000000) >> 24) + ); + + $keys[] = $temp; + } + + $temp = array( + CRYPT_DES_ENCRYPT => $keys, + CRYPT_DES_DECRYPT => array_reverse($keys) + ); + + return $temp; + } +} + +// vim: ts=4:sw=4:et: +// vim6: fdl=1:
\ No newline at end of file |