web/.ht-inc/phpseclib/Crypt/RC2.php - vcl - Git at Google

 <?php

 /**
  * Pure-PHP implementation of RC2.
  *
  * Uses mcrypt, if available, and an internal implementation, otherwise.
  *
  * PHP versions 4 and 5
  *
  * Useful resources are as follows:
  *
  *  - {@link http://tools.ietf.org/html/rfc2268}
  *
  * Here's a short example of how to use this library:
  * <code>
  * <?php
  *    include 'Crypt/RC2.php';
  *
  *    $rc2 = new Crypt_RC2();
  *
  *    $rc2->setKey('abcdefgh');
  *
  *    $plaintext = str_repeat('a', 1024);
  *
  *    echo $rc2->decrypt($rc2->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_RC2
  * @author   Patrick Monnerat <pm@datasphere.ch>
  * @license  http://www.opensource.org/licenses/mit-license.html  MIT License
  * @link     http://phpseclib.sourceforge.net
  */

 /**
  * Include Crypt_Base
  *
  * Base cipher class
  */
 if (!class_exists('Crypt_Base')) {
     include_once 'Base.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_RC2_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_RC2_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_RC2_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_RC2_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_RC2_MODE_OFB', CRYPT_MODE_OFB);
 /**#@-*/

 /**
  * Pure-PHP implementation of RC2.
  *
  * @package Crypt_RC2
  * @access  public
  */
 class Crypt_RC2 extends Crypt_Base
 {
     /**
      * Block Length of the cipher
      *
      * @see Crypt_Base::block_size
      * @var int
      * @access private
      */
     var $block_size = 8;

     /**
      * The Key
      *
      * @see Crypt_Base::key
      * @see self::setKey()
      * @var string
      * @access private
      */
     var $key;

     /**
      * The Original (unpadded) Key
      *
      * @see Crypt_Base::key
      * @see self::setKey()
      * @see self::encrypt()
      * @see self::decrypt()
      * @var string
      * @access private
      */
     var $orig_key;

     /**
      * Don't truncate / null pad key
      *
      * @see Crypt_Base::_clearBuffers()
      * @var bool
      * @access private
      */
     var $skip_key_adjustment = true;

     /**
      * Key Length (in bytes)
      *
      * @see Crypt_RC2::setKeyLength()
      * @var int
      * @access private
      */
     var $key_length = 16; // = 128 bits

     /**
      * The namespace used by the cipher for its constants.
      *
      * @see Crypt_Base::const_namespace
      * @var string
      * @access private
      */
     var $const_namespace = 'RC2';

     /**
      * The mcrypt specific name of the cipher
      *
      * @see Crypt_Base::cipher_name_mcrypt
      * @var string
      * @access private
      */
     var $cipher_name_mcrypt = 'rc2';

     /**
      * Optimizing value while CFB-encrypting
      *
      * @see Crypt_Base::cfb_init_len
      * @var int
      * @access private
      */
     var $cfb_init_len = 500;

     /**
      * The key length in bits.
      *
      * @see self::setKeyLength()
      * @see self::setKey()
      * @var int
      * @access private
      * @internal Should be in range [1..1024].
      * @internal Changing this value after setting the key has no effect.
      */
     var $default_key_length = 1024;

     /**
      * The key length in bits.
      *
      * @see self::isValidEnine()
      * @see self::setKey()
      * @var int
      * @access private
      * @internal Should be in range [1..1024].
      */
     var $current_key_length;

     /**
      * The Key Schedule
      *
      * @see self::_setupKey()
      * @var array
      * @access private
      */
     var $keys;

     /**
      * Key expansion randomization table.
      * Twice the same 256-value sequence to save a modulus in key expansion.
      *
      * @see self::setKey()
      * @var array
      * @access private
      */
     var $pitable = array(
         0xD9, 0x78, 0xF9, 0xC4, 0x19, 0xDD, 0xB5, 0xED,
         0x28, 0xE9, 0xFD, 0x79, 0x4A, 0xA0, 0xD8, 0x9D,
         0xC6, 0x7E, 0x37, 0x83, 0x2B, 0x76, 0x53, 0x8E,
         0x62, 0x4C, 0x64, 0x88, 0x44, 0x8B, 0xFB, 0xA2,
         0x17, 0x9A, 0x59, 0xF5, 0x87, 0xB3, 0x4F, 0x13,
         0x61, 0x45, 0x6D, 0x8D, 0x09, 0x81, 0x7D, 0x32,
         0xBD, 0x8F, 0x40, 0xEB, 0x86, 0xB7, 0x7B, 0x0B,
         0xF0, 0x95, 0x21, 0x22, 0x5C, 0x6B, 0x4E, 0x82,
         0x54, 0xD6, 0x65, 0x93, 0xCE, 0x60, 0xB2, 0x1C,
         0x73, 0x56, 0xC0, 0x14, 0xA7, 0x8C, 0xF1, 0xDC,
         0x12, 0x75, 0xCA, 0x1F, 0x3B, 0xBE, 0xE4, 0xD1,
         0x42, 0x3D, 0xD4, 0x30, 0xA3, 0x3C, 0xB6, 0x26,
         0x6F, 0xBF, 0x0E, 0xDA, 0x46, 0x69, 0x07, 0x57,
         0x27, 0xF2, 0x1D, 0x9B, 0xBC, 0x94, 0x43, 0x03,
         0xF8, 0x11, 0xC7, 0xF6, 0x90, 0xEF, 0x3E, 0xE7,
         0x06, 0xC3, 0xD5, 0x2F, 0xC8, 0x66, 0x1E, 0xD7,
         0x08, 0xE8, 0xEA, 0xDE, 0x80, 0x52, 0xEE, 0xF7,
         0x84, 0xAA, 0x72, 0xAC, 0x35, 0x4D, 0x6A, 0x2A,
         0x96, 0x1A, 0xD2, 0x71, 0x5A, 0x15, 0x49, 0x74,
         0x4B, 0x9F, 0xD0, 0x5E, 0x04, 0x18, 0xA4, 0xEC,
         0xC2, 0xE0, 0x41, 0x6E, 0x0F, 0x51, 0xCB, 0xCC,
         0x24, 0x91, 0xAF, 0x50, 0xA1, 0xF4, 0x70, 0x39,
         0x99, 0x7C, 0x3A, 0x85, 0x23, 0xB8, 0xB4, 0x7A,
         0xFC, 0x02, 0x36, 0x5B, 0x25, 0x55, 0x97, 0x31,
         0x2D, 0x5D, 0xFA, 0x98, 0xE3, 0x8A, 0x92, 0xAE,
         0x05, 0xDF, 0x29, 0x10, 0x67, 0x6C, 0xBA, 0xC9,
         0xD3, 0x00, 0xE6, 0xCF, 0xE1, 0x9E, 0xA8, 0x2C,
         0x63, 0x16, 0x01, 0x3F, 0x58, 0xE2, 0x89, 0xA9,
         0x0D, 0x38, 0x34, 0x1B, 0xAB, 0x33, 0xFF, 0xB0,
         0xBB, 0x48, 0x0C, 0x5F, 0xB9, 0xB1, 0xCD, 0x2E,
         0xC5, 0xF3, 0xDB, 0x47, 0xE5, 0xA5, 0x9C, 0x77,
         0x0A, 0xA6, 0x20, 0x68, 0xFE, 0x7F, 0xC1, 0xAD,
         0xD9, 0x78, 0xF9, 0xC4, 0x19, 0xDD, 0xB5, 0xED,
         0x28, 0xE9, 0xFD, 0x79, 0x4A, 0xA0, 0xD8, 0x9D,
         0xC6, 0x7E, 0x37, 0x83, 0x2B, 0x76, 0x53, 0x8E,
         0x62, 0x4C, 0x64, 0x88, 0x44, 0x8B, 0xFB, 0xA2,
         0x17, 0x9A, 0x59, 0xF5, 0x87, 0xB3, 0x4F, 0x13,
         0x61, 0x45, 0x6D, 0x8D, 0x09, 0x81, 0x7D, 0x32,
         0xBD, 0x8F, 0x40, 0xEB, 0x86, 0xB7, 0x7B, 0x0B,
         0xF0, 0x95, 0x21, 0x22, 0x5C, 0x6B, 0x4E, 0x82,
         0x54, 0xD6, 0x65, 0x93, 0xCE, 0x60, 0xB2, 0x1C,
         0x73, 0x56, 0xC0, 0x14, 0xA7, 0x8C, 0xF1, 0xDC,
         0x12, 0x75, 0xCA, 0x1F, 0x3B, 0xBE, 0xE4, 0xD1,
         0x42, 0x3D, 0xD4, 0x30, 0xA3, 0x3C, 0xB6, 0x26,
         0x6F, 0xBF, 0x0E, 0xDA, 0x46, 0x69, 0x07, 0x57,
         0x27, 0xF2, 0x1D, 0x9B, 0xBC, 0x94, 0x43, 0x03,
         0xF8, 0x11, 0xC7, 0xF6, 0x90, 0xEF, 0x3E, 0xE7,
         0x06, 0xC3, 0xD5, 0x2F, 0xC8, 0x66, 0x1E, 0xD7,
         0x08, 0xE8, 0xEA, 0xDE, 0x80, 0x52, 0xEE, 0xF7,
         0x84, 0xAA, 0x72, 0xAC, 0x35, 0x4D, 0x6A, 0x2A,
         0x96, 0x1A, 0xD2, 0x71, 0x5A, 0x15, 0x49, 0x74,
         0x4B, 0x9F, 0xD0, 0x5E, 0x04, 0x18, 0xA4, 0xEC,
         0xC2, 0xE0, 0x41, 0x6E, 0x0F, 0x51, 0xCB, 0xCC,
         0x24, 0x91, 0xAF, 0x50, 0xA1, 0xF4, 0x70, 0x39,
         0x99, 0x7C, 0x3A, 0x85, 0x23, 0xB8, 0xB4, 0x7A,
         0xFC, 0x02, 0x36, 0x5B, 0x25, 0x55, 0x97, 0x31,
         0x2D, 0x5D, 0xFA, 0x98, 0xE3, 0x8A, 0x92, 0xAE,
         0x05, 0xDF, 0x29, 0x10, 0x67, 0x6C, 0xBA, 0xC9,
         0xD3, 0x00, 0xE6, 0xCF, 0xE1, 0x9E, 0xA8, 0x2C,
         0x63, 0x16, 0x01, 0x3F, 0x58, 0xE2, 0x89, 0xA9,
         0x0D, 0x38, 0x34, 0x1B, 0xAB, 0x33, 0xFF, 0xB0,
         0xBB, 0x48, 0x0C, 0x5F, 0xB9, 0xB1, 0xCD, 0x2E,
         0xC5, 0xF3, 0xDB, 0x47, 0xE5, 0xA5, 0x9C, 0x77,
         0x0A, 0xA6, 0x20, 0x68, 0xFE, 0x7F, 0xC1, 0xAD
     );

     /**
      * Inverse key expansion randomization table.
      *
      * @see self::setKey()
      * @var array
      * @access private
      */
     var $invpitable = array(
         0xD1, 0xDA, 0xB9, 0x6F, 0x9C, 0xC8, 0x78, 0x66,
         0x80, 0x2C, 0xF8, 0x37, 0xEA, 0xE0, 0x62, 0xA4,
         0xCB, 0x71, 0x50, 0x27, 0x4B, 0x95, 0xD9, 0x20,
         0x9D, 0x04, 0x91, 0xE3, 0x47, 0x6A, 0x7E, 0x53,
         0xFA, 0x3A, 0x3B, 0xB4, 0xA8, 0xBC, 0x5F, 0x68,
         0x08, 0xCA, 0x8F, 0x14, 0xD7, 0xC0, 0xEF, 0x7B,
         0x5B, 0xBF, 0x2F, 0xE5, 0xE2, 0x8C, 0xBA, 0x12,
         0xE1, 0xAF, 0xB2, 0x54, 0x5D, 0x59, 0x76, 0xDB,
         0x32, 0xA2, 0x58, 0x6E, 0x1C, 0x29, 0x64, 0xF3,
         0xE9, 0x96, 0x0C, 0x98, 0x19, 0x8D, 0x3E, 0x26,
         0xAB, 0xA5, 0x85, 0x16, 0x40, 0xBD, 0x49, 0x67,
         0xDC, 0x22, 0x94, 0xBB, 0x3C, 0xC1, 0x9B, 0xEB,
         0x45, 0x28, 0x18, 0xD8, 0x1A, 0x42, 0x7D, 0xCC,
         0xFB, 0x65, 0x8E, 0x3D, 0xCD, 0x2A, 0xA3, 0x60,
         0xAE, 0x93, 0x8A, 0x48, 0x97, 0x51, 0x15, 0xF7,
         0x01, 0x0B, 0xB7, 0x36, 0xB1, 0x2E, 0x11, 0xFD,
         0x84, 0x2D, 0x3F, 0x13, 0x88, 0xB3, 0x34, 0x24,
         0x1B, 0xDE, 0xC5, 0x1D, 0x4D, 0x2B, 0x17, 0x31,
         0x74, 0xA9, 0xC6, 0x43, 0x6D, 0x39, 0x90, 0xBE,
         0xC3, 0xB0, 0x21, 0x6B, 0xF6, 0x0F, 0xD5, 0x99,
         0x0D, 0xAC, 0x1F, 0x5C, 0x9E, 0xF5, 0xF9, 0x4C,
         0xD6, 0xDF, 0x89, 0xE4, 0x8B, 0xFF, 0xC7, 0xAA,
         0xE7, 0xED, 0x46, 0x25, 0xB6, 0x06, 0x5E, 0x35,
         0xB5, 0xEC, 0xCE, 0xE8, 0x6C, 0x30, 0x55, 0x61,
         0x4A, 0xFE, 0xA0, 0x79, 0x03, 0xF0, 0x10, 0x72,
         0x7C, 0xCF, 0x52, 0xA6, 0xA7, 0xEE, 0x44, 0xD3,
         0x9A, 0x57, 0x92, 0xD0, 0x5A, 0x7A, 0x41, 0x7F,
         0x0E, 0x00, 0x63, 0xF2, 0x4F, 0x05, 0x83, 0xC9,
         0xA1, 0xD4, 0xDD, 0xC4, 0x56, 0xF4, 0xD2, 0x77,
         0x81, 0x09, 0x82, 0x33, 0x9F, 0x07, 0x86, 0x75,
         0x38, 0x4E, 0x69, 0xF1, 0xAD, 0x23, 0x73, 0x87,
         0x70, 0x02, 0xC2, 0x1E, 0xB8, 0x0A, 0xFC, 0xE6
     );

     /**
      * Test for engine validity
      *
      * This is mainly just a wrapper to set things up for Crypt_Base::isValidEngine()
      *
      * @see Crypt_Base::Crypt_Base()
      * @param int $engine
      * @access public
      * @return bool
      */
     function isValidEngine($engine)
     {
         switch ($engine) {
             case CRYPT_ENGINE_OPENSSL:
                 if ($this->current_key_length != 128 || strlen($this->orig_key) < 16) {
                     return false;
                 }
                 $this->cipher_name_openssl_ecb = 'rc2-ecb';
                 $this->cipher_name_openssl = 'rc2-' . $this->_openssl_translate_mode();
         }

         return parent::isValidEngine($engine);
     }

     /**
      * Sets the key length.
      *
      * Valid key lengths are 8 to 1024.
      * Calling this function after setting the key has no effect until the next
      *  Crypt_RC2::setKey() call.
      *
      * @access public
      * @param int $length in bits
      */
     function setKeyLength($length)
     {
         if ($length < 8) {
             $this->default_key_length = 8;
         } elseif ($length > 1024) {
             $this->default_key_length = 128;
         } else {
             $this->default_key_length = $length;
         }
         $this->current_key_length = $this->default_key_length;

         parent::setKeyLength($length);
     }

     /**
      * Returns the current key length
      *
      * @access public
      * @return int
      */
     function getKeyLength()
     {
         return $this->current_key_length;
     }

     /**
      * Sets the key.
      *
      * Keys can be of any length. RC2, itself, uses 8 to 1024 bit keys (eg.
      * strlen($key) <= 128), however, we only use the first 128 bytes if $key
      * has more then 128 bytes in it, and set $key to a single null byte if
      * it is empty.
      *
      * If the key is not explicitly set, it'll be assumed to be a single
      * null byte.
      *
      * @see Crypt_Base::setKey()
      * @access public
      * @param string $key
      * @param int $t1 optional Effective key length in bits.
      */
     function setKey($key, $t1 = 0)
     {
         $this->orig_key = $key;

         if ($t1 <= 0) {
             $t1 = $this->default_key_length;
         } elseif ($t1 > 1024) {
             $t1 = 1024;
         }
         $this->current_key_length = $t1;
         // Key byte count should be 1..128.
         $key = strlen($key) ? substr($key, 0, 128) : "\x00";
         $t = strlen($key);

         // The mcrypt RC2 implementation only supports effective key length
         // of 1024 bits. It is however possible to handle effective key
         // lengths in range 1..1024 by expanding the key and applying
         // inverse pitable mapping to the first byte before submitting it
         // to mcrypt.

         // Key expansion.
         $l = array_values(unpack('C*', $key));
         $t8 = ($t1 + 7) >> 3;
         $tm = 0xFF >> (8 * $t8 - $t1);

         // Expand key.
         $pitable = $this->pitable;
         for ($i = $t; $i < 128; $i++) {
             $l[$i] = $pitable[$l[$i - 1] + $l[$i - $t]];
         }
         $i = 128 - $t8;
         $l[$i] = $pitable[$l[$i] & $tm];
         while ($i--) {
             $l[$i] = $pitable[$l[$i + 1] ^ $l[$i + $t8]];
         }

         // Prepare the key for mcrypt.
         $l[0] = $this->invpitable[$l[0]];
         array_unshift($l, 'C*');

         parent::setKey(call_user_func_array('pack', $l));
     }

     /**
      * Encrypts a message.
      *
      * Mostly a wrapper for Crypt_Base::encrypt, with some additional OpenSSL handling code
      *
      * @see self::decrypt()
      * @access public
      * @param string $plaintext
      * @return string $ciphertext
      */
     function encrypt($plaintext)
     {
         if ($this->engine == CRYPT_ENGINE_OPENSSL) {
             $temp = $this->key;
             $this->key = $this->orig_key;
             $result = parent::encrypt($plaintext);
             $this->key = $temp;
             return $result;
         }

         return parent::encrypt($plaintext);
     }

     /**
      * Decrypts a message.
      *
      * Mostly a wrapper for Crypt_Base::decrypt, with some additional OpenSSL handling code
      *
      * @see self::encrypt()
      * @access public
      * @param string $ciphertext
      * @return string $plaintext
      */
     function decrypt($ciphertext)
     {
         if ($this->engine == CRYPT_ENGINE_OPENSSL) {
             $temp = $this->key;
             $this->key = $this->orig_key;
             $result = parent::decrypt($ciphertext);
             $this->key = $temp;
             return $result;
         }

         return parent::decrypt($ciphertext);
     }

     /**
      * Encrypts a block
      *
      * @see Crypt_Base::_encryptBlock()
      * @see Crypt_Base::encrypt()
      * @access private
      * @param string $in
      * @return string
      */
     function _encryptBlock($in)
     {
         list($r0, $r1, $r2, $r3) = array_values(unpack('v*', $in));
         $keys = $this->keys;
         $limit = 20;
         $actions = array($limit => 44, 44 => 64);
         $j = 0;

         for (;;) {
             // Mixing round.
             $r0 = (($r0 + $keys[$j++] + ((($r1 ^ $r2) & $r3) ^ $r1)) & 0xFFFF) << 1;
             $r0 |= $r0 >> 16;
             $r1 = (($r1 + $keys[$j++] + ((($r2 ^ $r3) & $r0) ^ $r2)) & 0xFFFF) << 2;
             $r1 |= $r1 >> 16;
             $r2 = (($r2 + $keys[$j++] + ((($r3 ^ $r0) & $r1) ^ $r3)) & 0xFFFF) << 3;
             $r2 |= $r2 >> 16;
             $r3 = (($r3 + $keys[$j++] + ((($r0 ^ $r1) & $r2) ^ $r0)) & 0xFFFF) << 5;
             $r3 |= $r3 >> 16;

             if ($j === $limit) {
                 if ($limit === 64) {
                     break;
                 }

                 // Mashing round.
                 $r0 += $keys[$r3 & 0x3F];
                 $r1 += $keys[$r0 & 0x3F];
                 $r2 += $keys[$r1 & 0x3F];
                 $r3 += $keys[$r2 & 0x3F];
                 $limit = $actions[$limit];
             }
         }

         return pack('vvvv', $r0, $r1, $r2, $r3);
     }

     /**
      * Decrypts a block
      *
      * @see Crypt_Base::_decryptBlock()
      * @see Crypt_Base::decrypt()
      * @access private
      * @param string $in
      * @return string
      */
     function _decryptBlock($in)
     {
         list($r0, $r1, $r2, $r3) = array_values(unpack('v*', $in));
         $keys = $this->keys;
         $limit = 44;
         $actions = array($limit => 20, 20 => 0);
         $j = 64;

         for (;;) {
             // R-mixing round.
             $r3 = ($r3 | ($r3 << 16)) >> 5;
             $r3 = ($r3 - $keys[--$j] - ((($r0 ^ $r1) & $r2) ^ $r0)) & 0xFFFF;
             $r2 = ($r2 | ($r2 << 16)) >> 3;
             $r2 = ($r2 - $keys[--$j] - ((($r3 ^ $r0) & $r1) ^ $r3)) & 0xFFFF;
             $r1 = ($r1 | ($r1 << 16)) >> 2;
             $r1 = ($r1 - $keys[--$j] - ((($r2 ^ $r3) & $r0) ^ $r2)) & 0xFFFF;
             $r0 = ($r0 | ($r0 << 16)) >> 1;
             $r0 = ($r0 - $keys[--$j] - ((($r1 ^ $r2) & $r3) ^ $r1)) & 0xFFFF;

             if ($j === $limit) {
                 if ($limit === 0) {
                     break;
                 }

                 // R-mashing round.
                 $r3 = ($r3 - $keys[$r2 & 0x3F]) & 0xFFFF;
                 $r2 = ($r2 - $keys[$r1 & 0x3F]) & 0xFFFF;
                 $r1 = ($r1 - $keys[$r0 & 0x3F]) & 0xFFFF;
                 $r0 = ($r0 - $keys[$r3 & 0x3F]) & 0xFFFF;
                 $limit = $actions[$limit];
             }
         }

         return pack('vvvv', $r0, $r1, $r2, $r3);
     }

     /**
      * Setup the CRYPT_ENGINE_MCRYPT $engine
      *
      * @see Crypt_Base::_setupMcrypt()
      * @access private
      */
     function _setupMcrypt()
     {
         if (!isset($this->key)) {
             $this->setKey('');
         }

         parent::_setupMcrypt();
     }

     /**
      * Creates the key schedule
      *
      * @see Crypt_Base::_setupKey()
      * @access private
      */
     function _setupKey()
     {
         if (!isset($this->key)) {
             $this->setKey('');
         }

         // Key has already been expanded in Crypt_RC2::setKey():
         // Only the first value must be altered.
         $l = unpack('Ca/Cb/v*', $this->key);
         array_unshift($l, $this->pitable[$l['a']] | ($l['b'] << 8));
         unset($l['a']);
         unset($l['b']);
         $this->keys = $l;
     }

     /**
      * Setup the performance-optimized function for de/encrypt()
      *
      * @see Crypt_Base::_setupInlineCrypt()
      * @access private
      */
     function _setupInlineCrypt()
     {
         $lambda_functions = &Crypt_RC2::_getLambdaFunctions();

         // The first 10 generated $lambda_functions will use the $keys hardcoded as integers
         // for the mixing rounds, for better inline crypt performance [~20% faster].
         // But for memory reason we have to limit those ultra-optimized $lambda_functions to an amount of 10.
         // (Currently, for Crypt_RC2, one generated $lambda_function cost on php5.5@32bit ~60kb unfreeable mem and ~100kb on php5.5@64bit)
         $gen_hi_opt_code = (bool)(count($lambda_functions) < 10);

         // Generation of a unique hash for our generated code
         $code_hash = "Crypt_RC2, {$this->mode}";
         if ($gen_hi_opt_code) {
             $code_hash = str_pad($code_hash, 32) . $this->_hashInlineCryptFunction($this->key);
         }

         // Is there a re-usable $lambda_functions in there?
         // If not, we have to create it.
         if (!isset($lambda_functions[$code_hash])) {
             // Init code for both, encrypt and decrypt.
             $init_crypt = '$keys = $self->keys;';

             switch (true) {
                 case $gen_hi_opt_code:
                     $keys = $this->keys;
                 default:
                     $keys = array();
                     foreach ($this->keys as $k => $v) {
                         $keys[$k] = '$keys[' . $k . ']';
                     }
             }

             // $in is the current 8 bytes block which has to be en/decrypt
             $encrypt_block = $decrypt_block = '
                 $in = unpack("v4", $in);
                 $r0 = $in[1];
                 $r1 = $in[2];
                 $r2 = $in[3];
                 $r3 = $in[4];
             ';

             // Create code for encryption.
             $limit = 20;
             $actions = array($limit => 44, 44 => 64);
             $j = 0;

             for (;;) {
                 // Mixing round.
                 $encrypt_block .= '
                     $r0 = (($r0 + ' . $keys[$j++] . ' +
                            ((($r1 ^ $r2) & $r3) ^ $r1)) & 0xFFFF) << 1;
                     $r0 |= $r0 >> 16;
                     $r1 = (($r1 + ' . $keys[$j++] . ' +
                            ((($r2 ^ $r3) & $r0) ^ $r2)) & 0xFFFF) << 2;
                     $r1 |= $r1 >> 16;
                     $r2 = (($r2 + ' . $keys[$j++] . ' +
                            ((($r3 ^ $r0) & $r1) ^ $r3)) & 0xFFFF) << 3;
                     $r2 |= $r2 >> 16;
                     $r3 = (($r3 + ' . $keys[$j++] . ' +
                            ((($r0 ^ $r1) & $r2) ^ $r0)) & 0xFFFF) << 5;
                     $r3 |= $r3 >> 16;';

                 if ($j === $limit) {
                     if ($limit === 64) {
                         break;
                     }

                     // Mashing round.
                     $encrypt_block .= '
                         $r0 += $keys[$r3 & 0x3F];
                         $r1 += $keys[$r0 & 0x3F];
                         $r2 += $keys[$r1 & 0x3F];
                         $r3 += $keys[$r2 & 0x3F];';
                     $limit = $actions[$limit];
                 }
             }

             $encrypt_block .= '$in = pack("v4", $r0, $r1, $r2, $r3);';

             // Create code for decryption.
             $limit = 44;
             $actions = array($limit => 20, 20 => 0);
             $j = 64;

             for (;;) {
                 // R-mixing round.
                 $decrypt_block .= '
                     $r3 = ($r3 | ($r3 << 16)) >> 5;
                     $r3 = ($r3 - ' . $keys[--$j] . ' -
                            ((($r0 ^ $r1) & $r2) ^ $r0)) & 0xFFFF;
                     $r2 = ($r2 | ($r2 << 16)) >> 3;
                     $r2 = ($r2 - ' . $keys[--$j] . ' -
                            ((($r3 ^ $r0) & $r1) ^ $r3)) & 0xFFFF;
                     $r1 = ($r1 | ($r1 << 16)) >> 2;
                     $r1 = ($r1 - ' . $keys[--$j] . ' -
                            ((($r2 ^ $r3) & $r0) ^ $r2)) & 0xFFFF;
                     $r0 = ($r0 | ($r0 << 16)) >> 1;
                     $r0 = ($r0 - ' . $keys[--$j] . ' -
                            ((($r1 ^ $r2) & $r3) ^ $r1)) & 0xFFFF;';

                 if ($j === $limit) {
                     if ($limit === 0) {
                         break;
                     }

                     // R-mashing round.
                     $decrypt_block .= '
                         $r3 = ($r3 - $keys[$r2 & 0x3F]) & 0xFFFF;
                         $r2 = ($r2 - $keys[$r1 & 0x3F]) & 0xFFFF;
                         $r1 = ($r1 - $keys[$r0 & 0x3F]) & 0xFFFF;
                         $r0 = ($r0 - $keys[$r3 & 0x3F]) & 0xFFFF;';
                     $limit = $actions[$limit];
                 }
             }

             $decrypt_block .= '$in = pack("v4", $r0, $r1, $r2, $r3);';

             // Creates the inline-crypt function
             $lambda_functions[$code_hash] = $this->_createInlineCryptFunction(
                 array(
                    'init_crypt'    => $init_crypt,
                    'encrypt_block' => $encrypt_block,
                    'decrypt_block' => $decrypt_block
                 )
             );
         }

         // Set the inline-crypt function as callback in: $this->inline_crypt
         $this->inline_crypt = $lambda_functions[$code_hash];
     }
 }
	<?php

	/**
	* Pure-PHP implementation of RC2.
	*
	* Uses mcrypt, if available, and an internal implementation, otherwise.
	*
	* PHP versions 4 and 5
	*
	* Useful resources are as follows:
	*
	* - {@link http://tools.ietf.org/html/rfc2268}
	*
	* Here's a short example of how to use this library:
	* <code>
	* <?php
	* include 'Crypt/RC2.php';
	*
	* $rc2 = new Crypt_RC2();
	*
	* $rc2->setKey('abcdefgh');
	*
	* $plaintext = str_repeat('a', 1024);
	*
	* echo $rc2->decrypt($rc2->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_RC2
	* @author Patrick Monnerat <pm@datasphere.ch>
	* @license http://www.opensource.org/licenses/mit-license.html MIT License
	* @link http://phpseclib.sourceforge.net
	*/

	/**
	* Include Crypt_Base
	*
	* Base cipher class
	*/
	if (!class_exists('Crypt_Base')) {
	include_once 'Base.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_RC2_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_RC2_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_RC2_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_RC2_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_RC2_MODE_OFB', CRYPT_MODE_OFB);
	/*#@-/

	/**
	* Pure-PHP implementation of RC2.
	*
	* @package Crypt_RC2
	* @access public
	*/
	class Crypt_RC2 extends Crypt_Base
	{
	/**
	* Block Length of the cipher
	*
	* @see Crypt_Base::block_size
	* @var int
	* @access private
	*/
	var $block_size = 8;

	/**
	* The Key
	*
	* @see Crypt_Base::key
	* @see self::setKey()
	* @var string
	* @access private
	*/
	var $key;

	/**
	* The Original (unpadded) Key
	*
	* @see Crypt_Base::key
	* @see self::setKey()
	* @see self::encrypt()
	* @see self::decrypt()
	* @var string
	* @access private
	*/
	var $orig_key;

	/**
	* Don't truncate / null pad key
	*
	* @see Crypt_Base::_clearBuffers()
	* @var bool
	* @access private
	*/
	var $skip_key_adjustment = true;

	/**
	* Key Length (in bytes)
	*
	* @see Crypt_RC2::setKeyLength()
	* @var int
	* @access private
	*/
	var $key_length = 16; // = 128 bits

	/**
	* The namespace used by the cipher for its constants.
	*
	* @see Crypt_Base::const_namespace
	* @var string
	* @access private
	*/
	var $const_namespace = 'RC2';

	/**
	* The mcrypt specific name of the cipher
	*
	* @see Crypt_Base::cipher_name_mcrypt
	* @var string
	* @access private
	*/
	var $cipher_name_mcrypt = 'rc2';

	/**
	* Optimizing value while CFB-encrypting
	*
	* @see Crypt_Base::cfb_init_len
	* @var int
	* @access private
	*/
	var $cfb_init_len = 500;

	/**
	* The key length in bits.
	*
	* @see self::setKeyLength()
	* @see self::setKey()
	* @var int
	* @access private
	* @internal Should be in range [1..1024].
	* @internal Changing this value after setting the key has no effect.
	*/
	var $default_key_length = 1024;

	/**
	* The key length in bits.
	*
	* @see self::isValidEnine()
	* @see self::setKey()
	* @var int
	* @access private
	* @internal Should be in range [1..1024].
	*/
	var $current_key_length;

	/**
	* The Key Schedule
	*
	* @see self::_setupKey()
	* @var array
	* @access private
	*/
	var $keys;

	/**
	* Key expansion randomization table.
	* Twice the same 256-value sequence to save a modulus in key expansion.
	*
	* @see self::setKey()
	* @var array
	* @access private
	*/
	var $pitable = array(
	0xD9, 0x78, 0xF9, 0xC4, 0x19, 0xDD, 0xB5, 0xED,
	0x28, 0xE9, 0xFD, 0x79, 0x4A, 0xA0, 0xD8, 0x9D,
	0xC6, 0x7E, 0x37, 0x83, 0x2B, 0x76, 0x53, 0x8E,
	0x62, 0x4C, 0x64, 0x88, 0x44, 0x8B, 0xFB, 0xA2,
	0x17, 0x9A, 0x59, 0xF5, 0x87, 0xB3, 0x4F, 0x13,
	0x61, 0x45, 0x6D, 0x8D, 0x09, 0x81, 0x7D, 0x32,
	0xBD, 0x8F, 0x40, 0xEB, 0x86, 0xB7, 0x7B, 0x0B,
	0xF0, 0x95, 0x21, 0x22, 0x5C, 0x6B, 0x4E, 0x82,
	0x54, 0xD6, 0x65, 0x93, 0xCE, 0x60, 0xB2, 0x1C,
	0x73, 0x56, 0xC0, 0x14, 0xA7, 0x8C, 0xF1, 0xDC,
	0x12, 0x75, 0xCA, 0x1F, 0x3B, 0xBE, 0xE4, 0xD1,
	0x42, 0x3D, 0xD4, 0x30, 0xA3, 0x3C, 0xB6, 0x26,
	0x6F, 0xBF, 0x0E, 0xDA, 0x46, 0x69, 0x07, 0x57,
	0x27, 0xF2, 0x1D, 0x9B, 0xBC, 0x94, 0x43, 0x03,
	0xF8, 0x11, 0xC7, 0xF6, 0x90, 0xEF, 0x3E, 0xE7,
	0x06, 0xC3, 0xD5, 0x2F, 0xC8, 0x66, 0x1E, 0xD7,
	0x08, 0xE8, 0xEA, 0xDE, 0x80, 0x52, 0xEE, 0xF7,
	0x84, 0xAA, 0x72, 0xAC, 0x35, 0x4D, 0x6A, 0x2A,
	0x96, 0x1A, 0xD2, 0x71, 0x5A, 0x15, 0x49, 0x74,
	0x4B, 0x9F, 0xD0, 0x5E, 0x04, 0x18, 0xA4, 0xEC,
	0xC2, 0xE0, 0x41, 0x6E, 0x0F, 0x51, 0xCB, 0xCC,
	0x24, 0x91, 0xAF, 0x50, 0xA1, 0xF4, 0x70, 0x39,
	0x99, 0x7C, 0x3A, 0x85, 0x23, 0xB8, 0xB4, 0x7A,
	0xFC, 0x02, 0x36, 0x5B, 0x25, 0x55, 0x97, 0x31,
	0x2D, 0x5D, 0xFA, 0x98, 0xE3, 0x8A, 0x92, 0xAE,
	0x05, 0xDF, 0x29, 0x10, 0x67, 0x6C, 0xBA, 0xC9,
	0xD3, 0x00, 0xE6, 0xCF, 0xE1, 0x9E, 0xA8, 0x2C,
	0x63, 0x16, 0x01, 0x3F, 0x58, 0xE2, 0x89, 0xA9,
	0x0D, 0x38, 0x34, 0x1B, 0xAB, 0x33, 0xFF, 0xB0,
	0xBB, 0x48, 0x0C, 0x5F, 0xB9, 0xB1, 0xCD, 0x2E,
	0xC5, 0xF3, 0xDB, 0x47, 0xE5, 0xA5, 0x9C, 0x77,
	0x0A, 0xA6, 0x20, 0x68, 0xFE, 0x7F, 0xC1, 0xAD,
	0xD9, 0x78, 0xF9, 0xC4, 0x19, 0xDD, 0xB5, 0xED,
	0x28, 0xE9, 0xFD, 0x79, 0x4A, 0xA0, 0xD8, 0x9D,
	0xC6, 0x7E, 0x37, 0x83, 0x2B, 0x76, 0x53, 0x8E,
	0x62, 0x4C, 0x64, 0x88, 0x44, 0x8B, 0xFB, 0xA2,
	0x17, 0x9A, 0x59, 0xF5, 0x87, 0xB3, 0x4F, 0x13,
	0x61, 0x45, 0x6D, 0x8D, 0x09, 0x81, 0x7D, 0x32,
	0xBD, 0x8F, 0x40, 0xEB, 0x86, 0xB7, 0x7B, 0x0B,
	0xF0, 0x95, 0x21, 0x22, 0x5C, 0x6B, 0x4E, 0x82,
	0x54, 0xD6, 0x65, 0x93, 0xCE, 0x60, 0xB2, 0x1C,
	0x73, 0x56, 0xC0, 0x14, 0xA7, 0x8C, 0xF1, 0xDC,
	0x12, 0x75, 0xCA, 0x1F, 0x3B, 0xBE, 0xE4, 0xD1,
	0x42, 0x3D, 0xD4, 0x30, 0xA3, 0x3C, 0xB6, 0x26,
	0x6F, 0xBF, 0x0E, 0xDA, 0x46, 0x69, 0x07, 0x57,
	0x27, 0xF2, 0x1D, 0x9B, 0xBC, 0x94, 0x43, 0x03,
	0xF8, 0x11, 0xC7, 0xF6, 0x90, 0xEF, 0x3E, 0xE7,
	0x06, 0xC3, 0xD5, 0x2F, 0xC8, 0x66, 0x1E, 0xD7,
	0x08, 0xE8, 0xEA, 0xDE, 0x80, 0x52, 0xEE, 0xF7,
	0x84, 0xAA, 0x72, 0xAC, 0x35, 0x4D, 0x6A, 0x2A,
	0x96, 0x1A, 0xD2, 0x71, 0x5A, 0x15, 0x49, 0x74,
	0x4B, 0x9F, 0xD0, 0x5E, 0x04, 0x18, 0xA4, 0xEC,
	0xC2, 0xE0, 0x41, 0x6E, 0x0F, 0x51, 0xCB, 0xCC,
	0x24, 0x91, 0xAF, 0x50, 0xA1, 0xF4, 0x70, 0x39,
	0x99, 0x7C, 0x3A, 0x85, 0x23, 0xB8, 0xB4, 0x7A,
	0xFC, 0x02, 0x36, 0x5B, 0x25, 0x55, 0x97, 0x31,
	0x2D, 0x5D, 0xFA, 0x98, 0xE3, 0x8A, 0x92, 0xAE,
	0x05, 0xDF, 0x29, 0x10, 0x67, 0x6C, 0xBA, 0xC9,
	0xD3, 0x00, 0xE6, 0xCF, 0xE1, 0x9E, 0xA8, 0x2C,
	0x63, 0x16, 0x01, 0x3F, 0x58, 0xE2, 0x89, 0xA9,
	0x0D, 0x38, 0x34, 0x1B, 0xAB, 0x33, 0xFF, 0xB0,
	0xBB, 0x48, 0x0C, 0x5F, 0xB9, 0xB1, 0xCD, 0x2E,
	0xC5, 0xF3, 0xDB, 0x47, 0xE5, 0xA5, 0x9C, 0x77,
	0x0A, 0xA6, 0x20, 0x68, 0xFE, 0x7F, 0xC1, 0xAD
	);

	/**
	* Inverse key expansion randomization table.
	*
	* @see self::setKey()
	* @var array
	* @access private
	*/
	var $invpitable = array(
	0xD1, 0xDA, 0xB9, 0x6F, 0x9C, 0xC8, 0x78, 0x66,
	0x80, 0x2C, 0xF8, 0x37, 0xEA, 0xE0, 0x62, 0xA4,
	0xCB, 0x71, 0x50, 0x27, 0x4B, 0x95, 0xD9, 0x20,
	0x9D, 0x04, 0x91, 0xE3, 0x47, 0x6A, 0x7E, 0x53,
	0xFA, 0x3A, 0x3B, 0xB4, 0xA8, 0xBC, 0x5F, 0x68,
	0x08, 0xCA, 0x8F, 0x14, 0xD7, 0xC0, 0xEF, 0x7B,
	0x5B, 0xBF, 0x2F, 0xE5, 0xE2, 0x8C, 0xBA, 0x12,
	0xE1, 0xAF, 0xB2, 0x54, 0x5D, 0x59, 0x76, 0xDB,
	0x32, 0xA2, 0x58, 0x6E, 0x1C, 0x29, 0x64, 0xF3,
	0xE9, 0x96, 0x0C, 0x98, 0x19, 0x8D, 0x3E, 0x26,
	0xAB, 0xA5, 0x85, 0x16, 0x40, 0xBD, 0x49, 0x67,
	0xDC, 0x22, 0x94, 0xBB, 0x3C, 0xC1, 0x9B, 0xEB,
	0x45, 0x28, 0x18, 0xD8, 0x1A, 0x42, 0x7D, 0xCC,
	0xFB, 0x65, 0x8E, 0x3D, 0xCD, 0x2A, 0xA3, 0x60,
	0xAE, 0x93, 0x8A, 0x48, 0x97, 0x51, 0x15, 0xF7,
	0x01, 0x0B, 0xB7, 0x36, 0xB1, 0x2E, 0x11, 0xFD,
	0x84, 0x2D, 0x3F, 0x13, 0x88, 0xB3, 0x34, 0x24,
	0x1B, 0xDE, 0xC5, 0x1D, 0x4D, 0x2B, 0x17, 0x31,
	0x74, 0xA9, 0xC6, 0x43, 0x6D, 0x39, 0x90, 0xBE,
	0xC3, 0xB0, 0x21, 0x6B, 0xF6, 0x0F, 0xD5, 0x99,
	0x0D, 0xAC, 0x1F, 0x5C, 0x9E, 0xF5, 0xF9, 0x4C,
	0xD6, 0xDF, 0x89, 0xE4, 0x8B, 0xFF, 0xC7, 0xAA,
	0xE7, 0xED, 0x46, 0x25, 0xB6, 0x06, 0x5E, 0x35,
	0xB5, 0xEC, 0xCE, 0xE8, 0x6C, 0x30, 0x55, 0x61,
	0x4A, 0xFE, 0xA0, 0x79, 0x03, 0xF0, 0x10, 0x72,
	0x7C, 0xCF, 0x52, 0xA6, 0xA7, 0xEE, 0x44, 0xD3,
	0x9A, 0x57, 0x92, 0xD0, 0x5A, 0x7A, 0x41, 0x7F,
	0x0E, 0x00, 0x63, 0xF2, 0x4F, 0x05, 0x83, 0xC9,
	0xA1, 0xD4, 0xDD, 0xC4, 0x56, 0xF4, 0xD2, 0x77,
	0x81, 0x09, 0x82, 0x33, 0x9F, 0x07, 0x86, 0x75,
	0x38, 0x4E, 0x69, 0xF1, 0xAD, 0x23, 0x73, 0x87,
	0x70, 0x02, 0xC2, 0x1E, 0xB8, 0x0A, 0xFC, 0xE6
	);

	/**
	* Test for engine validity
	*
	* This is mainly just a wrapper to set things up for Crypt_Base::isValidEngine()
	*
	* @see Crypt_Base::Crypt_Base()
	* @param int $engine
	* @access public
	* @return bool
	*/
	function isValidEngine($engine)
	{
	switch ($engine) {
	case CRYPT_ENGINE_OPENSSL:
	if ($this->current_key_length != 128 \|\| strlen($this->orig_key) < 16) {
	return false;
	}
	$this->cipher_name_openssl_ecb = 'rc2-ecb';
	$this->cipher_name_openssl = 'rc2-' . $this->_openssl_translate_mode();
	}

	return parent::isValidEngine($engine);
	}

	/**
	* Sets the key length.
	*
	* Valid key lengths are 8 to 1024.
	* Calling this function after setting the key has no effect until the next
	* Crypt_RC2::setKey() call.
	*
	* @access public
	* @param int $length in bits
	*/
	function setKeyLength($length)
	{
	if ($length < 8) {
	$this->default_key_length = 8;
	} elseif ($length > 1024) {
	$this->default_key_length = 128;
	} else {
	$this->default_key_length = $length;
	}
	$this->current_key_length = $this->default_key_length;

	parent::setKeyLength($length);
	}

	/**
	* Returns the current key length
	*
	* @access public
	* @return int
	*/
	function getKeyLength()
	{
	return $this->current_key_length;
	}

	/**
	* Sets the key.
	*
	* Keys can be of any length. RC2, itself, uses 8 to 1024 bit keys (eg.
	* strlen($key) <= 128), however, we only use the first 128 bytes if $key
	* has more then 128 bytes in it, and set $key to a single null byte if
	* it is empty.
	*
	* If the key is not explicitly set, it'll be assumed to be a single
	* null byte.
	*
	* @see Crypt_Base::setKey()
	* @access public
	* @param string $key
	* @param int $t1 optional Effective key length in bits.
	*/
	function setKey($key, $t1 = 0)
	{
	$this->orig_key = $key;

	if ($t1 <= 0) {
	$t1 = $this->default_key_length;
	} elseif ($t1 > 1024) {
	$t1 = 1024;
	}
	$this->current_key_length = $t1;
	// Key byte count should be 1..128.
	$key = strlen($key) ? substr($key, 0, 128) : "\x00";
	$t = strlen($key);

	// The mcrypt RC2 implementation only supports effective key length
	// of 1024 bits. It is however possible to handle effective key
	// lengths in range 1..1024 by expanding the key and applying
	// inverse pitable mapping to the first byte before submitting it
	// to mcrypt.

	// Key expansion.
	$l = array_values(unpack('C*', $key));
	$t8 = ($t1 + 7) >> 3;
	$tm = 0xFF >> (8 * $t8 - $t1);

	// Expand key.
	$pitable = $this->pitable;
	for ($i = $t; $i < 128; $i++) {
	$l[$i] = $pitable[$l[$i - 1] + $l[$i - $t]];
	}
	$i = 128 - $t8;
	$l[$i] = $pitable[$l[$i] & $tm];
	while ($i--) {
	$l[$i] = $pitable[$l[$i + 1] ^ $l[$i + $t8]];
	}

	// Prepare the key for mcrypt.
	$l[0] = $this->invpitable[$l[0]];
	array_unshift($l, 'C*');

	parent::setKey(call_user_func_array('pack', $l));
	}

	/**
	* Encrypts a message.
	*
	* Mostly a wrapper for Crypt_Base::encrypt, with some additional OpenSSL handling code
	*
	* @see self::decrypt()
	* @access public
	* @param string $plaintext
	* @return string $ciphertext
	*/
	function encrypt($plaintext)
	{
	if ($this->engine == CRYPT_ENGINE_OPENSSL) {
	$temp = $this->key;
	$this->key = $this->orig_key;
	$result = parent::encrypt($plaintext);
	$this->key = $temp;
	return $result;
	}

	return parent::encrypt($plaintext);
	}

	/**
	* Decrypts a message.
	*
	* Mostly a wrapper for Crypt_Base::decrypt, with some additional OpenSSL handling code
	*
	* @see self::encrypt()
	* @access public
	* @param string $ciphertext
	* @return string $plaintext
	*/
	function decrypt($ciphertext)
	{
	if ($this->engine == CRYPT_ENGINE_OPENSSL) {
	$temp = $this->key;
	$this->key = $this->orig_key;
	$result = parent::decrypt($ciphertext);
	$this->key = $temp;
	return $result;
	}

	return parent::decrypt($ciphertext);
	}

	/**
	* Encrypts a block
	*
	* @see Crypt_Base::_encryptBlock()
	* @see Crypt_Base::encrypt()
	* @access private
	* @param string $in
	* @return string
	*/
	function _encryptBlock($in)
	{
	list($r0, $r1, $r2, $r3) = array_values(unpack('v*', $in));
	$keys = $this->keys;
	$limit = 20;
	$actions = array($limit => 44, 44 => 64);
	$j = 0;

	for (;;) {
	// Mixing round.
	$r0 = (($r0 + $keys[$j++] + ((($r1 ^ $r2) & $r3) ^ $r1)) & 0xFFFF) << 1;
	$r0 \|= $r0 >> 16;
	$r1 = (($r1 + $keys[$j++] + ((($r2 ^ $r3) & $r0) ^ $r2)) & 0xFFFF) << 2;
	$r1 \|= $r1 >> 16;
	$r2 = (($r2 + $keys[$j++] + ((($r3 ^ $r0) & $r1) ^ $r3)) & 0xFFFF) << 3;
	$r2 \|= $r2 >> 16;
	$r3 = (($r3 + $keys[$j++] + ((($r0 ^ $r1) & $r2) ^ $r0)) & 0xFFFF) << 5;
	$r3 \|= $r3 >> 16;

	if ($j === $limit) {
	if ($limit === 64) {
	break;
	}

	// Mashing round.
	$r0 += $keys[$r3 & 0x3F];
	$r1 += $keys[$r0 & 0x3F];
	$r2 += $keys[$r1 & 0x3F];
	$r3 += $keys[$r2 & 0x3F];
	$limit = $actions[$limit];
	}
	}

	return pack('vvvv', $r0, $r1, $r2, $r3);
	}

	/**
	* Decrypts a block
	*
	* @see Crypt_Base::_decryptBlock()
	* @see Crypt_Base::decrypt()
	* @access private
	* @param string $in
	* @return string
	*/
	function _decryptBlock($in)
	{
	list($r0, $r1, $r2, $r3) = array_values(unpack('v*', $in));
	$keys = $this->keys;
	$limit = 44;
	$actions = array($limit => 20, 20 => 0);
	$j = 64;

	for (;;) {
	// R-mixing round.
	$r3 = ($r3 \| ($r3 << 16)) >> 5;
	$r3 = ($r3 - $keys[--$j] - ((($r0 ^ $r1) & $r2) ^ $r0)) & 0xFFFF;
	$r2 = ($r2 \| ($r2 << 16)) >> 3;
	$r2 = ($r2 - $keys[--$j] - ((($r3 ^ $r0) & $r1) ^ $r3)) & 0xFFFF;
	$r1 = ($r1 \| ($r1 << 16)) >> 2;
	$r1 = ($r1 - $keys[--$j] - ((($r2 ^ $r3) & $r0) ^ $r2)) & 0xFFFF;
	$r0 = ($r0 \| ($r0 << 16)) >> 1;
	$r0 = ($r0 - $keys[--$j] - ((($r1 ^ $r2) & $r3) ^ $r1)) & 0xFFFF;

	if ($j === $limit) {
	if ($limit === 0) {
	break;
	}

	// R-mashing round.
	$r3 = ($r3 - $keys[$r2 & 0x3F]) & 0xFFFF;
	$r2 = ($r2 - $keys[$r1 & 0x3F]) & 0xFFFF;
	$r1 = ($r1 - $keys[$r0 & 0x3F]) & 0xFFFF;
	$r0 = ($r0 - $keys[$r3 & 0x3F]) & 0xFFFF;
	$limit = $actions[$limit];
	}
	}

	return pack('vvvv', $r0, $r1, $r2, $r3);
	}

	/**
	* Setup the CRYPT_ENGINE_MCRYPT $engine
	*
	* @see Crypt_Base::_setupMcrypt()
	* @access private
	*/
	function _setupMcrypt()
	{
	if (!isset($this->key)) {
	$this->setKey('');
	}

	parent::_setupMcrypt();
	}

	/**
	* Creates the key schedule
	*
	* @see Crypt_Base::_setupKey()
	* @access private
	*/
	function _setupKey()
	{
	if (!isset($this->key)) {
	$this->setKey('');
	}

	// Key has already been expanded in Crypt_RC2::setKey():
	// Only the first value must be altered.
	$l = unpack('Ca/Cb/v*', $this->key);
	array_unshift($l, $this->pitable[$l['a']] \| ($l['b'] << 8));
	unset($l['a']);
	unset($l['b']);
	$this->keys = $l;
	}

	/**
	* Setup the performance-optimized function for de/encrypt()
	*
	* @see Crypt_Base::_setupInlineCrypt()
	* @access private
	*/
	function _setupInlineCrypt()
	{
	$lambda_functions = &Crypt_RC2::_getLambdaFunctions();

	// The first 10 generated $lambda_functions will use the $keys hardcoded as integers
	// for the mixing rounds, for better inline crypt performance [~20% faster].
	// But for memory reason we have to limit those ultra-optimized $lambda_functions to an amount of 10.
	// (Currently, for Crypt_RC2, one generated $lambda_function cost on php5.5@32bit ~60kb unfreeable mem and ~100kb on php5.5@64bit)
	$gen_hi_opt_code = (bool)(count($lambda_functions) < 10);

	// Generation of a unique hash for our generated code
	$code_hash = "Crypt_RC2, {$this->mode}";
	if ($gen_hi_opt_code) {
	$code_hash = str_pad($code_hash, 32) . $this->_hashInlineCryptFunction($this->key);
	}

	// Is there a re-usable $lambda_functions in there?
	// If not, we have to create it.
	if (!isset($lambda_functions[$code_hash])) {
	// Init code for both, encrypt and decrypt.
	$init_crypt = '$keys = $self->keys;';

	switch (true) {
	case $gen_hi_opt_code:
	$keys = $this->keys;
	default:
	$keys = array();
	foreach ($this->keys as $k => $v) {
	$keys[$k] = '$keys[' . $k . ']';
	}
	}

	// $in is the current 8 bytes block which has to be en/decrypt
	$encrypt_block = $decrypt_block = '
	$in = unpack("v4", $in);
	$r0 = $in[1];
	$r1 = $in[2];
	$r2 = $in[3];
	$r3 = $in[4];
	';

	// Create code for encryption.
	$limit = 20;
	$actions = array($limit => 44, 44 => 64);
	$j = 0;

	for (;;) {
	// Mixing round.
	$encrypt_block .= '
	$r0 = (($r0 + ' . $keys[$j++] . ' +
	((($r1 ^ $r2) & $r3) ^ $r1)) & 0xFFFF) << 1;
	$r0 \|= $r0 >> 16;
	$r1 = (($r1 + ' . $keys[$j++] . ' +
	((($r2 ^ $r3) & $r0) ^ $r2)) & 0xFFFF) << 2;
	$r1 \|= $r1 >> 16;
	$r2 = (($r2 + ' . $keys[$j++] . ' +
	((($r3 ^ $r0) & $r1) ^ $r3)) & 0xFFFF) << 3;
	$r2 \|= $r2 >> 16;
	$r3 = (($r3 + ' . $keys[$j++] . ' +
	((($r0 ^ $r1) & $r2) ^ $r0)) & 0xFFFF) << 5;
	$r3 \|= $r3 >> 16;';

	if ($j === $limit) {
	if ($limit === 64) {
	break;
	}

	// Mashing round.
	$encrypt_block .= '
	$r0 += $keys[$r3 & 0x3F];
	$r1 += $keys[$r0 & 0x3F];
	$r2 += $keys[$r1 & 0x3F];
	$r3 += $keys[$r2 & 0x3F];';
	$limit = $actions[$limit];
	}
	}

	$encrypt_block .= '$in = pack("v4", $r0, $r1, $r2, $r3);';

	// Create code for decryption.
	$limit = 44;
	$actions = array($limit => 20, 20 => 0);
	$j = 64;

	for (;;) {
	// R-mixing round.
	$decrypt_block .= '
	$r3 = ($r3 \| ($r3 << 16)) >> 5;
	$r3 = ($r3 - ' . $keys[--$j] . ' -
	((($r0 ^ $r1) & $r2) ^ $r0)) & 0xFFFF;
	$r2 = ($r2 \| ($r2 << 16)) >> 3;
	$r2 = ($r2 - ' . $keys[--$j] . ' -
	((($r3 ^ $r0) & $r1) ^ $r3)) & 0xFFFF;
	$r1 = ($r1 \| ($r1 << 16)) >> 2;
	$r1 = ($r1 - ' . $keys[--$j] . ' -
	((($r2 ^ $r3) & $r0) ^ $r2)) & 0xFFFF;
	$r0 = ($r0 \| ($r0 << 16)) >> 1;
	$r0 = ($r0 - ' . $keys[--$j] . ' -
	((($r1 ^ $r2) & $r3) ^ $r1)) & 0xFFFF;';

	if ($j === $limit) {
	if ($limit === 0) {
	break;
	}

	// R-mashing round.
	$decrypt_block .= '
	$r3 = ($r3 - $keys[$r2 & 0x3F]) & 0xFFFF;
	$r2 = ($r2 - $keys[$r1 & 0x3F]) & 0xFFFF;
	$r1 = ($r1 - $keys[$r0 & 0x3F]) & 0xFFFF;
	$r0 = ($r0 - $keys[$r3 & 0x3F]) & 0xFFFF;';
	$limit = $actions[$limit];
	}
	}

	$decrypt_block .= '$in = pack("v4", $r0, $r1, $r2, $r3);';

	// Creates the inline-crypt function
	$lambda_functions[$code_hash] = $this->_createInlineCryptFunction(
	array(
	'init_crypt' => $init_crypt,
	'encrypt_block' => $encrypt_block,
	'decrypt_block' => $decrypt_block
	)
	);
	}

	// Set the inline-crypt function as callback in: $this->inline_crypt
	$this->inline_crypt = $lambda_functions[$code_hash];
	}
	}