<?php

/**
 * Pure-PHP implementation of Rijndael.
 *
 * Uses mcrypt, if available/possible, and an internal implementation, otherwise.
 *
 * PHP versions 4 and 5
 *
 * If {@link Crypt_Rijndael::setBlockLength() setBlockLength()} isn't called, it'll be assumed to be 128 bits.  If
 * {@link Crypt_Rijndael::setKeyLength() setKeyLength()} isn't called, it'll be calculated from
 * {@link Crypt_Rijndael::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 192-bits and 192 bits will be the key length until
 * {@link Crypt_Rijndael::setKey() setKey()} is called, again, at which point, it'll be recalculated.
 *
 * Not all Rijndael implementations may support 160-bits or 224-bits as the block length / key length.  mcrypt, for example,
 * does not.  AES, itself, only supports block lengths of 128 and key lengths of 128, 192, and 256.
 * {@link http://csrc.nist.gov/archive/aes/rijndael/Rijndael-ammended.pdf#page=10 Rijndael-ammended.pdf#page=10} defines the
 * algorithm for block lengths of 192 and 256 but not for block lengths / key lengths of 160 and 224.  Indeed, 160 and 224
 * are first defined as valid key / block lengths in
 * {@link http://csrc.nist.gov/archive/aes/rijndael/Rijndael-ammended.pdf#page=44 Rijndael-ammended.pdf#page=44}:
 * Extensions: Other block and Cipher Key lengths.
 * Note: Use of 160/224-bit Keys must be explicitly set by setKeyLength(160) respectively setKeyLength(224).
 *
 * {@internal The variable names are the same as those in
 * {@link http://www.csrc.nist.gov/publications/fips/fips197/fips-197.pdf#page=10 fips-197.pdf#page=10}.}}
 *
 * Here's a short example of how to use this library:
 * <code>
 * <?php
 *    include 'Crypt/Rijndael.php';
 *
 *    $rijndael = new Crypt_Rijndael();
 *
 *    $rijndael->setKey('abcdefghijklmnop');
 *
 *    $size = 10 * 1024;
 *    $plaintext = '';
 *    for ($i = 0; $i < $size; $i++) {
 *        $plaintext.= 'a';
 *    }
 *
 *    echo $rijndael->decrypt($rijndael->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_Rijndael
 * @author    Jim Wigginton <terrafrost@php.net>
 * @copyright MMVIII Jim Wigginton
 * @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 Crypt_Rijndael::encrypt()
 * @see Crypt_Rijndael::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_RIJNDAEL_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_RIJNDAEL_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_RIJNDAEL_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_RIJNDAEL_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_RIJNDAEL_MODE_OFB', CRYPT_MODE_OFB);
/**#@-*/

/**#@+
 * @access private
 * @see Crypt_Base::Crypt_Base()
 */
/**
 * Toggles the internal implementation
 */
define('CRYPT_RIJNDAEL_MODE_INTERNAL', CRYPT_MODE_INTERNAL);
/**
 * Toggles the mcrypt implementation
 */
define('CRYPT_RIJNDAEL_MODE_MCRYPT', CRYPT_MODE_MCRYPT);
/**#@-*/

/**
 * Pure-PHP implementation of Rijndael.
 *
 * @package Crypt_Rijndael
 * @author  Jim Wigginton <terrafrost@php.net>
 * @access  public
 */
class Crypt_Rijndael extends Crypt_Base
{
    /**
     * The default password key_size used by setPassword()
     *
     * @see Crypt_Base::password_key_size
     * @see Crypt_Base::setPassword()
     * @var Integer
     * @access private
     */
    var $password_key_size = 16;

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

    /**
     * The mcrypt specific name of the cipher
     *
     * Mcrypt is useable for 128/192/256-bit $block_size/$key_size. For 160/224 not.
     * Crypt_Rijndael determines automatically whether mcrypt is useable
     * or not for the current $block_size/$key_size.
     * In case of, $cipher_name_mcrypt will be set dynamically at run time accordingly.
     *
     * @see Crypt_Base::cipher_name_mcrypt
     * @see Crypt_Base::engine
     * @see _setupEngine()
     * @var String
     * @access private
     */
    var $cipher_name_mcrypt = 'rijndael-128';

    /**
     * The default salt used by setPassword()
     *
     * @see Crypt_Base::password_default_salt
     * @see Crypt_Base::setPassword()
     * @var String
     * @access private
     */
    var $password_default_salt = 'phpseclib';

    /**
     * Has the key length explicitly been set or should it be derived from the key, itself?
     *
     * @see setKeyLength()
     * @var Boolean
     * @access private
     */
    var $explicit_key_length = false;

    /**
     * The Key Schedule
     *
     * @see _setup()
     * @var Array
     * @access private
     */
    var $w;

    /**
     * The Inverse Key Schedule
     *
     * @see _setup()
     * @var Array
     * @access private
     */
    var $dw;

    /**
     * The Block Length divided by 32
     *
     * @see setBlockLength()
     * @var Integer
     * @access private
     * @internal The max value is 256 / 32 = 8, the min value is 128 / 32 = 4.  Exists in conjunction with $block_size
     *    because the encryption / decryption / key schedule creation requires this number and not $block_size.  We could
     *    derive this from $block_size or vice versa, but that'd mean we'd have to do multiple shift operations, so in lieu
     *    of that, we'll just precompute it once.
     *
     */
    var $Nb = 4;

    /**
     * The Key Length
     *
     * @see setKeyLength()
     * @var Integer
     * @access private
     * @internal The max value is 256 / 8 = 32, the min value is 128 / 8 = 16.  Exists in conjunction with $Nk
     *    because the encryption / decryption / key schedule creation requires this number and not $key_size.  We could
     *    derive this from $key_size or vice versa, but that'd mean we'd have to do multiple shift operations, so in lieu
     *    of that, we'll just precompute it once.
     */
    var $key_size = 16;

    /**
     * The Key Length divided by 32
     *
     * @see setKeyLength()
     * @var Integer
     * @access private
     * @internal The max value is 256 / 32 = 8, the min value is 128 / 32 = 4
     */
    var $Nk = 4;

    /**
     * The Number of Rounds
     *
     * @var Integer
     * @access private
     * @internal The max value is 14, the min value is 10.
     */
    var $Nr;

    /**
     * Shift offsets
     *
     * @var Array
     * @access private
     */
    var $c;

    /**
     * Holds the last used key- and block_size information
     *
     * @var Array
     * @access private
     */
    var $kl;

    /**
     * Precomputed mixColumns table
     *
     * According to <http://csrc.nist.gov/archive/aes/rijndael/Rijndael-ammended.pdf#page=19> (section 5.2.1),
     * precomputed tables can be used in the mixColumns phase.  in that example, they're assigned t0...t3, so
     * those are the names we'll use.
     *
     * @see Crypt_Rijndael:_encryptBlock()
     * @see Crypt_Rijndael:_decryptBlock()
     * @var Array
     * @access private
     */
    var $t0 = array(
        0xC66363A5, 0xF87C7C84, 0xEE777799, 0xF67B7B8D, 0xFFF2F20D, 0xD66B6BBD, 0xDE6F6FB1, 0x91C5C554,
        0x60303050, 0x02010103, 0xCE6767A9, 0x562B2B7D, 0xE7FEFE19, 0xB5D7D762, 0x4DABABE6, 0xEC76769A,
        0x8FCACA45, 0x1F82829D, 0x89C9C940, 0xFA7D7D87, 0xEFFAFA15, 0xB25959EB, 0x8E4747C9, 0xFBF0F00B,
        0x41ADADEC, 0xB3D4D467, 0x5FA2A2FD, 0x45AFAFEA, 0x239C9CBF, 0x53A4A4F7, 0xE4727296, 0x9BC0C05B,
        0x75B7B7C2, 0xE1FDFD1C, 0x3D9393AE, 0x4C26266A, 0x6C36365A, 0x7E3F3F41, 0xF5F7F702, 0x83CCCC4F,
        0x6834345C, 0x51A5A5F4, 0xD1E5E534, 0xF9F1F108, 0xE2717193, 0xABD8D873, 0x62313153, 0x2A15153F,
        0x0804040C, 0x95C7C752, 0x46232365, 0x9DC3C35E, 0x30181828, 0x379696A1, 0x0A05050F, 0x2F9A9AB5,
        0x0E070709, 0x24121236, 0x1B80809B, 0xDFE2E23D, 0xCDEBEB26, 0x4E272769, 0x7FB2B2CD, 0xEA75759F,
        0x1209091B, 0x1D83839E, 0x582C2C74, 0x341A1A2E, 0x361B1B2D, 0xDC6E6EB2, 0xB45A5AEE, 0x5BA0A0FB,
        0xA45252F6, 0x763B3B4D, 0xB7D6D661, 0x7DB3B3CE, 0x5229297B, 0xDDE3E33E, 0x5E2F2F71, 0x13848497,
        0xA65353F5, 0xB9D1D168, 0x00000000, 0xC1EDED2C, 0x40202060, 0xE3FCFC1F, 0x79B1B1C8, 0xB65B5BED,
        0xD46A6ABE, 0x8DCBCB46, 0x67BEBED9, 0x7239394B, 0x944A4ADE, 0x984C4CD4, 0xB05858E8, 0x85CFCF4A,
        0xBBD0D06B, 0xC5EFEF2A, 0x4FAAAAE5, 0xEDFBFB16, 0x864343C5, 0x9A4D4DD7, 0x66333355, 0x11858594,
        0x8A4545CF, 0xE9F9F910, 0x04020206, 0xFE7F7F81, 0xA05050F0, 0x783C3C44, 0x259F9FBA, 0x4BA8A8E3,
        0xA25151F3, 0x5DA3A3FE, 0x804040C0, 0x058F8F8A, 0x3F9292AD, 0x219D9DBC, 0x70383848, 0xF1F5F504,
        0x63BCBCDF, 0x77B6B6C1, 0xAFDADA75, 0x42212163, 0x20101030, 0xE5FFFF1A, 0xFDF3F30E, 0xBFD2D26D,
        0x81CDCD4C, 0x180C0C14, 0x26131335, 0xC3ECEC2F, 0xBE5F5FE1, 0x359797A2, 0x884444CC, 0x2E171739,
        0x93C4C457, 0x55A7A7F2, 0xFC7E7E82, 0x7A3D3D47, 0xC86464AC, 0xBA5D5DE7, 0x3219192B, 0xE6737395,
        0xC06060A0, 0x19818198, 0x9E4F4FD1, 0xA3DCDC7F, 0x44222266, 0x542A2A7E, 0x3B9090AB, 0x0B888883,
        0x8C4646CA, 0xC7EEEE29, 0x6BB8B8D3, 0x2814143C, 0xA7DEDE79, 0xBC5E5EE2, 0x160B0B1D, 0xADDBDB76,
        0xDBE0E03B, 0x64323256, 0x743A3A4E, 0x140A0A1E, 0x924949DB, 0x0C06060A, 0x4824246C, 0xB85C5CE4,
        0x9FC2C25D, 0xBDD3D36E, 0x43ACACEF, 0xC46262A6, 0x399191A8, 0x319595A4, 0xD3E4E437, 0xF279798B,
        0xD5E7E732, 0x8BC8C843, 0x6E373759, 0xDA6D6DB7, 0x018D8D8C, 0xB1D5D564, 0x9C4E4ED2, 0x49A9A9E0,
        0xD86C6CB4, 0xAC5656FA, 0xF3F4F407, 0xCFEAEA25, 0xCA6565AF, 0xF47A7A8E, 0x47AEAEE9, 0x10080818,
        0x6FBABAD5, 0xF0787888, 0x4A25256F, 0x5C2E2E72, 0x381C1C24, 0x57A6A6F1, 0x73B4B4C7, 0x97C6C651,
        0xCBE8E823, 0xA1DDDD7C, 0xE874749C, 0x3E1F1F21, 0x964B4BDD, 0x61BDBDDC, 0x0D8B8B86, 0x0F8A8A85,
        0xE0707090, 0x7C3E3E42, 0x71B5B5C4, 0xCC6666AA, 0x904848D8, 0x06030305, 0xF7F6F601, 0x1C0E0E12,
        0xC26161A3, 0x6A35355F, 0xAE5757F9, 0x69B9B9D0, 0x17868691, 0x99C1C158, 0x3A1D1D27, 0x279E9EB9,
        0xD9E1E138, 0xEBF8F813, 0x2B9898B3, 0x22111133, 0xD26969BB, 0xA9D9D970, 0x078E8E89, 0x339494A7,
        0x2D9B9BB6, 0x3C1E1E22, 0x15878792, 0xC9E9E920, 0x87CECE49, 0xAA5555FF, 0x50282878, 0xA5DFDF7A,
        0x038C8C8F, 0x59A1A1F8, 0x09898980, 0x1A0D0D17, 0x65BFBFDA, 0xD7E6E631, 0x844242C6, 0xD06868B8,
        0x824141C3, 0x299999B0, 0x5A2D2D77, 0x1E0F0F11, 0x7BB0B0CB, 0xA85454FC, 0x6DBBBBD6, 0x2C16163A
    );

    /**
     * Precomputed mixColumns table
     *
     * @see Crypt_Rijndael:_encryptBlock()
     * @see Crypt_Rijndael:_decryptBlock()
     * @var Array
     * @access private
     */
    var $t1 = array(
        0xA5C66363, 0x84F87C7C, 0x99EE7777, 0x8DF67B7B, 0x0DFFF2F2, 0xBDD66B6B, 0xB1DE6F6F, 0x5491C5C5,
        0x50603030, 0x03020101, 0xA9CE6767, 0x7D562B2B, 0x19E7FEFE, 0x62B5D7D7, 0xE64DABAB, 0x9AEC7676,
        0x458FCACA, 0x9D1F8282, 0x4089C9C9, 0x87FA7D7D, 0x15EFFAFA, 0xEBB25959, 0xC98E4747, 0x0BFBF0F0,
        0xEC41ADAD, 0x67B3D4D4, 0xFD5FA2A2, 0xEA45AFAF, 0xBF239C9C, 0xF753A4A4, 0x96E47272, 0x5B9BC0C0,
        0xC275B7B7, 0x1CE1FDFD, 0xAE3D9393, 0x6A4C2626, 0x5A6C3636, 0x417E3F3F, 0x02F5F7F7, 0x4F83CCCC,
        0x5C683434, 0xF451A5A5, 0x34D1E5E5, 0x08F9F1F1, 0x93E27171, 0x73ABD8D8, 0x53623131, 0x3F2A1515,
        0x0C080404, 0x5295C7C7, 0x65462323, 0x5E9DC3C3, 0x28301818, 0xA1379696, 0x0F0A0505, 0xB52F9A9A,
        0x090E0707, 0x36241212, 0x9B1B8080, 0x3DDFE2E2, 0x26CDEBEB, 0x694E2727, 0xCD7FB2B2, 0x9FEA7575,
        0x1B120909, 0x9E1D8383, 0x74582C2C, 0x2E341A1A, 0x2D361B1B, 0xB2DC6E6E, 0xEEB45A5A, 0xFB5BA0A0,
        0xF6A45252, 0x4D763B3B, 0x61B7D6D6, 0xCE7DB3B3, 0x7B522929, 0x3EDDE3E3, 0x715E2F2F, 0x97138484,
        0xF5A65353, 0x68B9D1D1, 0x00000000, 0x2CC1EDED, 0x60402020, 0x1FE3FCFC, 0xC879B1B1, 0xEDB65B5B,
        0xBED46A6A, 0x468DCBCB, 0xD967BEBE, 0x4B723939, 0xDE944A4A, 0xD4984C4C, 0xE8B05858, 0x4A85CFCF,
        0x6BBBD0D0, 0x2AC5EFEF, 0xE54FAAAA, 0x16EDFBFB, 0xC5864343, 0xD79A4D4D, 0x55663333, 0x94118585,
        0xCF8A4545, 0x10E9F9F9, 0x06040202, 0x81FE7F7F, 0xF0A05050, 0x44783C3C, 0xBA259F9F, 0xE34BA8A8,
        0xF3A25151, 0xFE5DA3A3, 0xC0804040, 0x8A058F8F, 0xAD3F9292, 0xBC219D9D, 0x48703838, 0x04F1F5F5,
        0xDF63BCBC, 0xC177B6B6, 0x75AFDADA, 0x63422121, 0x30201010, 0x1AE5FFFF, 0x0EFDF3F3, 0x6DBFD2D2,
        0x4C81CDCD, 0x14180C0C, 0x35261313, 0x2FC3ECEC, 0xE1BE5F5F, 0xA2359797, 0xCC884444, 0x392E1717,
        0x5793C4C4, 0xF255A7A7, 0x82FC7E7E, 0x477A3D3D, 0xACC86464, 0xE7BA5D5D, 0x2B321919, 0x95E67373,
        0xA0C06060, 0x98198181, 0xD19E4F4F, 0x7FA3DCDC, 0x66442222, 0x7E542A2A, 0xAB3B9090, 0x830B8888,
        0xCA8C4646, 0x29C7EEEE, 0xD36BB8B8, 0x3C281414, 0x79A7DEDE, 0xE2BC5E5E, 0x1D160B0B, 0x76ADDBDB,
        0x3BDBE0E0, 0x56643232, 0x4E743A3A, 0x1E140A0A, 0xDB924949, 0x0A0C0606, 0x6C482424, 0xE4B85C5C,
        0x5D9FC2C2, 0x6EBDD3D3, 0xEF43ACAC, 0xA6C46262, 0xA8399191, 0xA4319595, 0x37D3E4E4, 0x8BF27979,
        0x32D5E7E7, 0x438BC8C8, 0x596E3737, 0xB7DA6D6D, 0x8C018D8D, 0x64B1D5D5, 0xD29C4E4E, 0xE049A9A9,
        0xB4D86C6C, 0xFAAC5656, 0x07F3F4F4, 0x25CFEAEA, 0xAFCA6565, 0x8EF47A7A, 0xE947AEAE, 0x18100808,
        0xD56FBABA, 0x88F07878, 0x6F4A2525, 0x725C2E2E, 0x24381C1C, 0xF157A6A6, 0xC773B4B4, 0x5197C6C6,
        0x23CBE8E8, 0x7CA1DDDD, 0x9CE87474, 0x213E1F1F, 0xDD964B4B, 0xDC61BDBD, 0x860D8B8B, 0x850F8A8A,
        0x90E07070, 0x427C3E3E, 0xC471B5B5, 0xAACC6666, 0xD8904848, 0x05060303, 0x01F7F6F6, 0x121C0E0E,
        0xA3C26161, 0x5F6A3535, 0xF9AE5757, 0xD069B9B9, 0x91178686, 0x5899C1C1, 0x273A1D1D, 0xB9279E9E,
        0x38D9E1E1, 0x13EBF8F8, 0xB32B9898, 0x33221111, 0xBBD26969, 0x70A9D9D9, 0x89078E8E, 0xA7339494,
        0xB62D9B9B, 0x223C1E1E, 0x92158787, 0x20C9E9E9, 0x4987CECE, 0xFFAA5555, 0x78502828, 0x7AA5DFDF,
        0x8F038C8C, 0xF859A1A1, 0x80098989, 0x171A0D0D, 0xDA65BFBF, 0x31D7E6E6, 0xC6844242, 0xB8D06868,
        0xC3824141, 0xB0299999, 0x775A2D2D, 0x111E0F0F, 0xCB7BB0B0, 0xFCA85454, 0xD66DBBBB, 0x3A2C1616
    );

    /**
     * Precomputed mixColumns table
     *
     * @see Crypt_Rijndael:_encryptBlock()
     * @see Crypt_Rijndael:_decryptBlock()
     * @var Array
     * @access private
     */
    var $t2 = array(
        0x63A5C663, 0x7C84F87C, 0x7799EE77, 0x7B8DF67B, 0xF20DFFF2, 0x6BBDD66B, 0x6FB1DE6F, 0xC55491C5,
        0x30506030, 0x01030201, 0x67A9CE67, 0x2B7D562B, 0xFE19E7FE, 0xD762B5D7, 0xABE64DAB, 0x769AEC76,
        0xCA458FCA, 0x829D1F82, 0xC94089C9, 0x7D87FA7D, 0xFA15EFFA, 0x59EBB259, 0x47C98E47, 0xF00BFBF0,
        0xADEC41AD, 0xD467B3D4, 0xA2FD5FA2, 0xAFEA45AF, 0x9CBF239C, 0xA4F753A4, 0x7296E472, 0xC05B9BC0,
        0xB7C275B7, 0xFD1CE1FD, 0x93AE3D93, 0x266A4C26, 0x365A6C36, 0x3F417E3F, 0xF702F5F7, 0xCC4F83CC,
        0x345C6834, 0xA5F451A5, 0xE534D1E5, 0xF108F9F1, 0x7193E271, 0xD873ABD8, 0x31536231, 0x153F2A15,
        0x040C0804, 0xC75295C7, 0x23654623, 0xC35E9DC3, 0x18283018, 0x96A13796, 0x050F0A05, 0x9AB52F9A,
        0x07090E07, 0x12362412, 0x809B1B80, 0xE23DDFE2, 0xEB26CDEB, 0x27694E27, 0xB2CD7FB2, 0x759FEA75,
        0x091B1209, 0x839E1D83, 0x2C74582C, 0x1A2E341A, 0x1B2D361B, 0x6EB2DC6E, 0x5AEEB45A, 0xA0FB5BA0,
        0x52F6A452, 0x3B4D763B, 0xD661B7D6, 0xB3CE7DB3, 0x297B5229, 0xE33EDDE3, 0x2F715E2F, 0x84971384,
        0x53F5A653, 0xD168B9D1, 0x00000000, 0xED2CC1ED, 0x20604020, 0xFC1FE3FC, 0xB1C879B1, 0x5BEDB65B,
        0x6ABED46A, 0xCB468DCB, 0xBED967BE, 0x394B7239, 0x4ADE944A, 0x4CD4984C, 0x58E8B058, 0xCF4A85CF,
        0xD06BBBD0, 0xEF2AC5EF, 0xAAE54FAA, 0xFB16EDFB, 0x43C58643, 0x4DD79A4D, 0x33556633, 0x85941185,
        0x45CF8A45, 0xF910E9F9, 0x02060402, 0x7F81FE7F, 0x50F0A050, 0x3C44783C, 0x9FBA259F, 0xA8E34BA8,
        0x51F3A251, 0xA3FE5DA3, 0x40C08040, 0x8F8A058F, 0x92AD3F92, 0x9DBC219D, 0x38487038, 0xF504F1F5,
        0xBCDF63BC, 0xB6C177B6, 0xDA75AFDA, 0x21634221, 0x10302010, 0xFF1AE5FF, 0xF30EFDF3, 0xD26DBFD2,
        0xCD4C81CD, 0x0C14180C, 0x13352613, 0xEC2FC3EC, 0x5FE1BE5F, 0x97A23597, 0x44CC8844, 0x17392E17,
        0xC45793C4, 0xA7F255A7, 0x7E82FC7E, 0x3D477A3D, 0x64ACC864, 0x5DE7BA5D, 0x192B3219, 0x7395E673,
        0x60A0C060, 0x81981981, 0x4FD19E4F, 0xDC7FA3DC, 0x22664422, 0x2A7E542A, 0x90AB3B90, 0x88830B88,
        0x46CA8C46, 0xEE29C7EE, 0xB8D36BB8, 0x143C2814, 0xDE79A7DE, 0x5EE2BC5E, 0x0B1D160B, 0xDB76ADDB,
        0xE03BDBE0, 0x32566432, 0x3A4E743A, 0x0A1E140A, 0x49DB9249, 0x060A0C06, 0x246C4824, 0x5CE4B85C,
        0xC25D9FC2, 0xD36EBDD3, 0xACEF43AC, 0x62A6C462, 0x91A83991, 0x95A43195, 0xE437D3E4, 0x798BF279,
        0xE732D5E7, 0xC8438BC8, 0x37596E37, 0x6DB7DA6D, 0x8D8C018D, 0xD564B1D5, 0x4ED29C4E, 0xA9E049A9,
        0x6CB4D86C, 0x56FAAC56, 0xF407F3F4, 0xEA25CFEA, 0x65AFCA65, 0x7A8EF47A, 0xAEE947AE, 0x08181008,
        0xBAD56FBA, 0x7888F078, 0x256F4A25, 0x2E725C2E, 0x1C24381C, 0xA6F157A6, 0xB4C773B4, 0xC65197C6,
        0xE823CBE8, 0xDD7CA1DD, 0x749CE874, 0x1F213E1F, 0x4BDD964B, 0xBDDC61BD, 0x8B860D8B, 0x8A850F8A,
        0x7090E070, 0x3E427C3E, 0xB5C471B5, 0x66AACC66, 0x48D89048, 0x03050603, 0xF601F7F6, 0x0E121C0E,
        0x61A3C261, 0x355F6A35, 0x57F9AE57, 0xB9D069B9, 0x86911786, 0xC15899C1, 0x1D273A1D, 0x9EB9279E,
        0xE138D9E1, 0xF813EBF8, 0x98B32B98, 0x11332211, 0x69BBD269, 0xD970A9D9, 0x8E89078E, 0x94A73394,
        0x9BB62D9B, 0x1E223C1E, 0x87921587, 0xE920C9E9, 0xCE4987CE, 0x55FFAA55, 0x28785028, 0xDF7AA5DF,
        0x8C8F038C, 0xA1F859A1, 0x89800989, 0x0D171A0D, 0xBFDA65BF, 0xE631D7E6, 0x42C68442, 0x68B8D068,
        0x41C38241, 0x99B02999, 0x2D775A2D, 0x0F111E0F, 0xB0CB7BB0, 0x54FCA854, 0xBBD66DBB, 0x163A2C16
    );

    /**
     * Precomputed mixColumns table
     *
     * @see Crypt_Rijndael:_encryptBlock()
     * @see Crypt_Rijndael:_decryptBlock()
     * @var Array
     * @access private
     */
    var $t3 = array(
        0x6363A5C6, 0x7C7C84F8, 0x777799EE, 0x7B7B8DF6, 0xF2F20DFF, 0x6B6BBDD6, 0x6F6FB1DE, 0xC5C55491,
        0x30305060, 0x01010302, 0x6767A9CE, 0x2B2B7D56, 0xFEFE19E7, 0xD7D762B5, 0xABABE64D, 0x76769AEC,
        0xCACA458F, 0x82829D1F, 0xC9C94089, 0x7D7D87FA, 0xFAFA15EF, 0x5959EBB2, 0x4747C98E, 0xF0F00BFB,
        0xADADEC41, 0xD4D467B3, 0xA2A2FD5F, 0xAFAFEA45, 0x9C9CBF23, 0xA4A4F753, 0x727296E4, 0xC0C05B9B,
        0xB7B7C275, 0xFDFD1CE1, 0x9393AE3D, 0x26266A4C, 0x36365A6C, 0x3F3F417E, 0xF7F702F5, 0xCCCC4F83,
        0x34345C68, 0xA5A5F451, 0xE5E534D1, 0xF1F108F9, 0x717193E2, 0xD8D873AB, 0x31315362, 0x15153F2A,
        0x04040C08, 0xC7C75295, 0x23236546, 0xC3C35E9D, 0x18182830, 0x9696A137, 0x05050F0A, 0x9A9AB52F,
        0x0707090E, 0x12123624, 0x80809B1B, 0xE2E23DDF, 0xEBEB26CD, 0x2727694E, 0xB2B2CD7F, 0x75759FEA,
        0x09091B12, 0x83839E1D, 0x2C2C7458, 0x1A1A2E34, 0x1B1B2D36, 0x6E6EB2DC, 0x5A5AEEB4, 0xA0A0FB5B,
        0x5252F6A4, 0x3B3B4D76, 0xD6D661B7, 0xB3B3CE7D, 0x29297B52, 0xE3E33EDD, 0x2F2F715E, 0x84849713,
        0x5353F5A6, 0xD1D168B9, 0x00000000, 0xEDED2CC1, 0x20206040, 0xFCFC1FE3, 0xB1B1C879, 0x5B5BEDB6,
        0x6A6ABED4, 0xCBCB468D, 0xBEBED967, 0x39394B72, 0x4A4ADE94, 0x4C4CD498, 0x5858E8B0, 0xCFCF4A85,
        0xD0D06BBB, 0xEFEF2AC5, 0xAAAAE54F, 0xFBFB16ED, 0x4343C586, 0x4D4DD79A, 0x33335566, 0x85859411,
        0x4545CF8A, 0xF9F910E9, 0x02020604, 0x7F7F81FE, 0x5050F0A0, 0x3C3C4478, 0x9F9FBA25, 0xA8A8E34B,
        0x5151F3A2, 0xA3A3FE5D, 0x4040C080, 0x8F8F8A05, 0x9292AD3F, 0x9D9DBC21, 0x38384870, 0xF5F504F1,
        0xBCBCDF63, 0xB6B6C177, 0xDADA75AF, 0x21216342, 0x10103020, 0xFFFF1AE5, 0xF3F30EFD, 0xD2D26DBF,
        0xCDCD4C81, 0x0C0C1418, 0x13133526, 0xECEC2FC3, 0x5F5FE1BE, 0x9797A235, 0x4444CC88, 0x1717392E,
        0xC4C45793, 0xA7A7F255, 0x7E7E82FC, 0x3D3D477A, 0x6464ACC8, 0x5D5DE7BA, 0x19192B32, 0x737395E6,
        0x6060A0C0, 0x81819819, 0x4F4FD19E, 0xDCDC7FA3, 0x22226644, 0x2A2A7E54, 0x9090AB3B, 0x8888830B,
        0x4646CA8C, 0xEEEE29C7, 0xB8B8D36B, 0x14143C28, 0xDEDE79A7, 0x5E5EE2BC, 0x0B0B1D16, 0xDBDB76AD,
        0xE0E03BDB, 0x32325664, 0x3A3A4E74, 0x0A0A1E14, 0x4949DB92, 0x06060A0C, 0x24246C48, 0x5C5CE4B8,
        0xC2C25D9F, 0xD3D36EBD, 0xACACEF43, 0x6262A6C4, 0x9191A839, 0x9595A431, 0xE4E437D3, 0x79798BF2,
        0xE7E732D5, 0xC8C8438B, 0x3737596E, 0x6D6DB7DA, 0x8D8D8C01, 0xD5D564B1, 0x4E4ED29C, 0xA9A9E049,
        0x6C6CB4D8, 0x5656FAAC, 0xF4F407F3, 0xEAEA25CF, 0x6565AFCA, 0x7A7A8EF4, 0xAEAEE947, 0x08081810,
        0xBABAD56F, 0x787888F0, 0x25256F4A, 0x2E2E725C, 0x1C1C2438, 0xA6A6F157, 0xB4B4C773, 0xC6C65197,
        0xE8E823CB, 0xDDDD7CA1, 0x74749CE8, 0x1F1F213E, 0x4B4BDD96, 0xBDBDDC61, 0x8B8B860D, 0x8A8A850F,
        0x707090E0, 0x3E3E427C, 0xB5B5C471, 0x6666AACC, 0x4848D890, 0x03030506, 0xF6F601F7, 0x0E0E121C,
        0x6161A3C2, 0x35355F6A, 0x5757F9AE, 0xB9B9D069, 0x86869117, 0xC1C15899, 0x1D1D273A, 0x9E9EB927,
        0xE1E138D9, 0xF8F813EB, 0x9898B32B, 0x11113322, 0x6969BBD2, 0xD9D970A9, 0x8E8E8907, 0x9494A733,
        0x9B9BB62D, 0x1E1E223C, 0x87879215, 0xE9E920C9, 0xCECE4987, 0x5555FFAA, 0x28287850, 0xDFDF7AA5,
        0x8C8C8F03, 0xA1A1F859, 0x89898009, 0x0D0D171A, 0xBFBFDA65, 0xE6E631D7, 0x4242C684, 0x6868B8D0,
        0x4141C382, 0x9999B029, 0x2D2D775A, 0x0F0F111E, 0xB0B0CB7B, 0x5454FCA8, 0xBBBBD66D, 0x16163A2C
    );

    /**
     * Precomputed invMixColumns table
     *
     * @see Crypt_Rijndael:_encryptBlock()
     * @see Crypt_Rijndael:_decryptBlock()
     * @var Array
     * @access private
     */
    var $dt0 = array(
        0x51F4A750, 0x7E416553, 0x1A17A4C3, 0x3A275E96, 0x3BAB6BCB, 0x1F9D45F1, 0xACFA58AB, 0x4BE30393,
        0x2030FA55, 0xAD766DF6, 0x88CC7691, 0xF5024C25, 0x4FE5D7FC, 0xC52ACBD7, 0x26354480, 0xB562A38F,
        0xDEB15A49, 0x25BA1B67, 0x45EA0E98, 0x5DFEC0E1, 0xC32F7502, 0x814CF012, 0x8D4697A3, 0x6BD3F9C6,
        0x038F5FE7, 0x15929C95, 0xBF6D7AEB, 0x955259DA, 0xD4BE832D, 0x587421D3, 0x49E06929, 0x8EC9C844,
        0x75C2896A, 0xF48E7978, 0x99583E6B, 0x27B971DD, 0xBEE14FB6, 0xF088AD17, 0xC920AC66, 0x7DCE3AB4,
        0x63DF4A18, 0xE51A3182, 0x97513360, 0x62537F45, 0xB16477E0, 0xBB6BAE84, 0xFE81A01C, 0xF9082B94,
        0x70486858, 0x8F45FD19, 0x94DE6C87, 0x527BF8B7, 0xAB73D323, 0x724B02E2, 0xE31F8F57, 0x6655AB2A,
        0xB2EB2807, 0x2FB5C203, 0x86C57B9A, 0xD33708A5, 0x302887F2, 0x23BFA5B2, 0x02036ABA, 0xED16825C,
        0x8ACF1C2B, 0xA779B492, 0xF307F2F0, 0x4E69E2A1, 0x65DAF4CD, 0x0605BED5, 0xD134621F, 0xC4A6FE8A,
        0x342E539D, 0xA2F355A0, 0x058AE132, 0xA4F6EB75, 0x0B83EC39, 0x4060EFAA, 0x5E719F06, 0xBD6E1051,
        0x3E218AF9, 0x96DD063D, 0xDD3E05AE, 0x4DE6BD46, 0x91548DB5, 0x71C45D05, 0x0406D46F, 0x605015FF,
        0x1998FB24, 0xD6BDE997, 0x894043CC, 0x67D99E77, 0xB0E842BD, 0x07898B88, 0xE7195B38, 0x79C8EEDB,
        0xA17C0A47, 0x7C420FE9, 0xF8841EC9, 0x00000000, 0x09808683, 0x322BED48, 0x1E1170AC, 0x6C5A724E,
        0xFD0EFFFB, 0x0F853856, 0x3DAED51E, 0x362D3927, 0x0A0FD964, 0x685CA621, 0x9B5B54D1, 0x24362E3A,
        0x0C0A67B1, 0x9357E70F, 0xB4EE96D2, 0x1B9B919E, 0x80C0C54F, 0x61DC20A2, 0x5A774B69, 0x1C121A16,
        0xE293BA0A, 0xC0A02AE5, 0x3C22E043, 0x121B171D, 0x0E090D0B, 0xF28BC7AD, 0x2DB6A8B9, 0x141EA9C8,
        0x57F11985, 0xAF75074C, 0xEE99DDBB, 0xA37F60FD, 0xF701269F, 0x5C72F5BC, 0x44663BC5, 0x5BFB7E34,
        0x8B432976, 0xCB23C6DC, 0xB6EDFC68, 0xB8E4F163, 0xD731DCCA, 0x42638510, 0x13972240, 0x84C61120,
        0x854A247D, 0xD2BB3DF8, 0xAEF93211, 0xC729A16D, 0x1D9E2F4B, 0xDCB230F3, 0x0D8652EC, 0x77C1E3D0,
        0x2BB3166C, 0xA970B999, 0x119448FA, 0x47E96422, 0xA8FC8CC4, 0xA0F03F1A, 0x567D2CD8, 0x223390EF,
        0x87494EC7, 0xD938D1C1, 0x8CCAA2FE, 0x98D40B36, 0xA6F581CF, 0xA57ADE28, 0xDAB78E26, 0x3FADBFA4,
        0x2C3A9DE4, 0x5078920D, 0x6A5FCC9B, 0x547E4662, 0xF68D13C2, 0x90D8B8E8, 0x2E39F75E, 0x82C3AFF5,
        0x9F5D80BE, 0x69D0937C, 0x6FD52DA9, 0xCF2512B3, 0xC8AC993B, 0x10187DA7, 0xE89C636E, 0xDB3BBB7B,
        0xCD267809, 0x6E5918F4, 0xEC9AB701, 0x834F9AA8, 0xE6956E65, 0xAAFFE67E, 0x21BCCF08, 0xEF15E8E6,
        0xBAE79BD9, 0x4A6F36CE, 0xEA9F09D4, 0x29B07CD6, 0x31A4B2AF, 0x2A3F2331, 0xC6A59430, 0x35A266C0,
        0x744EBC37, 0xFC82CAA6, 0xE090D0B0, 0x33A7D815, 0xF104984A, 0x41ECDAF7, 0x7FCD500E, 0x1791F62F,
        0x764DD68D, 0x43EFB04D, 0xCCAA4D54, 0xE49604DF, 0x9ED1B5E3, 0x4C6A881B, 0xC12C1FB8, 0x4665517F,
        0x9D5EEA04, 0x018C355D, 0xFA877473, 0xFB0B412E, 0xB3671D5A, 0x92DBD252, 0xE9105633, 0x6DD64713,
        0x9AD7618C, 0x37A10C7A, 0x59F8148E, 0xEB133C89, 0xCEA927EE, 0xB761C935, 0xE11CE5ED, 0x7A47B13C,
        0x9CD2DF59, 0x55F2733F, 0x1814CE79, 0x73C737BF, 0x53F7CDEA, 0x5FFDAA5B, 0xDF3D6F14, 0x7844DB86,
        0xCAAFF381, 0xB968C43E, 0x3824342C, 0xC2A3405F, 0x161DC372, 0xBCE2250C, 0x283C498B, 0xFF0D9541,
        0x39A80171, 0x080CB3DE, 0xD8B4E49C, 0x6456C190, 0x7BCB8461, 0xD532B670, 0x486C5C74, 0xD0B85742
    );

    /**
     * Precomputed invMixColumns table
     *
     * @see Crypt_Rijndael:_encryptBlock()
     * @see Crypt_Rijndael:_decryptBlock()
     * @var Array
     * @access private
     */
    var $dt1 = array(
        0x5051F4A7, 0x537E4165, 0xC31A17A4, 0x963A275E, 0xCB3BAB6B, 0xF11F9D45, 0xABACFA58, 0x934BE303,
        0x552030FA, 0xF6AD766D, 0x9188CC76, 0x25F5024C, 0xFC4FE5D7, 0xD7C52ACB, 0x80263544, 0x8FB562A3,
        0x49DEB15A, 0x6725BA1B, 0x9845EA0E, 0xE15DFEC0, 0x02C32F75, 0x12814CF0, 0xA38D4697, 0xC66BD3F9,
        0xE7038F5F, 0x9515929C, 0xEBBF6D7A, 0xDA955259, 0x2DD4BE83, 0xD3587421, 0x2949E069, 0x448EC9C8,
        0x6A75C289, 0x78F48E79, 0x6B99583E, 0xDD27B971, 0xB6BEE14F, 0x17F088AD, 0x66C920AC, 0xB47DCE3A,
        0x1863DF4A, 0x82E51A31, 0x60975133, 0x4562537F, 0xE0B16477, 0x84BB6BAE, 0x1CFE81A0, 0x94F9082B,
        0x58704868, 0x198F45FD, 0x8794DE6C, 0xB7527BF8, 0x23AB73D3, 0xE2724B02, 0x57E31F8F, 0x2A6655AB,
        0x07B2EB28, 0x032FB5C2, 0x9A86C57B, 0xA5D33708, 0xF2302887, 0xB223BFA5, 0xBA02036A, 0x5CED1682,
        0x2B8ACF1C, 0x92A779B4, 0xF0F307F2, 0xA14E69E2, 0xCD65DAF4, 0xD50605BE, 0x1FD13462, 0x8AC4A6FE,
        0x9D342E53, 0xA0A2F355, 0x32058AE1, 0x75A4F6EB, 0x390B83EC, 0xAA4060EF, 0x065E719F, 0x51BD6E10,
        0xF93E218A, 0x3D96DD06, 0xAEDD3E05, 0x464DE6BD, 0xB591548D, 0x0571C45D, 0x6F0406D4, 0xFF605015,
        0x241998FB, 0x97D6BDE9, 0xCC894043, 0x7767D99E, 0xBDB0E842, 0x8807898B, 0x38E7195B, 0xDB79C8EE,
        0x47A17C0A, 0xE97C420F, 0xC9F8841E, 0x00000000, 0x83098086, 0x48322BED, 0xAC1E1170, 0x4E6C5A72,
        0xFBFD0EFF, 0x560F8538, 0x1E3DAED5, 0x27362D39, 0x640A0FD9, 0x21685CA6, 0xD19B5B54, 0x3A24362E,
        0xB10C0A67, 0x0F9357E7, 0xD2B4EE96, 0x9E1B9B91, 0x4F80C0C5, 0xA261DC20, 0x695A774B, 0x161C121A,
        0x0AE293BA, 0xE5C0A02A, 0x433C22E0, 0x1D121B17, 0x0B0E090D, 0xADF28BC7, 0xB92DB6A8, 0xC8141EA9,
        0x8557F119, 0x4CAF7507, 0xBBEE99DD, 0xFDA37F60, 0x9FF70126, 0xBC5C72F5, 0xC544663B, 0x345BFB7E,
        0x768B4329, 0xDCCB23C6, 0x68B6EDFC, 0x63B8E4F1, 0xCAD731DC, 0x10426385, 0x40139722, 0x2084C611,
        0x7D854A24, 0xF8D2BB3D, 0x11AEF932, 0x6DC729A1, 0x4B1D9E2F, 0xF3DCB230, 0xEC0D8652, 0xD077C1E3,
        0x6C2BB316, 0x99A970B9, 0xFA119448, 0x2247E964, 0xC4A8FC8C, 0x1AA0F03F, 0xD8567D2C, 0xEF223390,
        0xC787494E, 0xC1D938D1, 0xFE8CCAA2, 0x3698D40B, 0xCFA6F581, 0x28A57ADE, 0x26DAB78E, 0xA43FADBF,
        0xE42C3A9D, 0x0D507892, 0x9B6A5FCC, 0x62547E46, 0xC2F68D13, 0xE890D8B8, 0x5E2E39F7, 0xF582C3AF,
        0xBE9F5D80, 0x7C69D093, 0xA96FD52D, 0xB3CF2512, 0x3BC8AC99, 0xA710187D, 0x6EE89C63, 0x7BDB3BBB,
        0x09CD2678, 0xF46E5918, 0x01EC9AB7, 0xA8834F9A, 0x65E6956E, 0x7EAAFFE6, 0x0821BCCF, 0xE6EF15E8,
        0xD9BAE79B, 0xCE4A6F36, 0xD4EA9F09, 0xD629B07C, 0xAF31A4B2, 0x312A3F23, 0x30C6A594, 0xC035A266,
        0x37744EBC, 0xA6FC82CA, 0xB0E090D0, 0x1533A7D8, 0x4AF10498, 0xF741ECDA, 0x0E7FCD50, 0x2F1791F6,
        0x8D764DD6, 0x4D43EFB0, 0x54CCAA4D, 0xDFE49604, 0xE39ED1B5, 0x1B4C6A88, 0xB8C12C1F, 0x7F466551,
        0x049D5EEA, 0x5D018C35, 0x73FA8774, 0x2EFB0B41, 0x5AB3671D, 0x5292DBD2, 0x33E91056, 0x136DD647,
        0x8C9AD761, 0x7A37A10C, 0x8E59F814, 0x89EB133C, 0xEECEA927, 0x35B761C9, 0xEDE11CE5, 0x3C7A47B1,
        0x599CD2DF, 0x3F55F273, 0x791814CE, 0xBF73C737, 0xEA53F7CD, 0x5B5FFDAA, 0x14DF3D6F, 0x867844DB,
        0x81CAAFF3, 0x3EB968C4, 0x2C382434, 0x5FC2A340, 0x72161DC3, 0x0CBCE225, 0x8B283C49, 0x41FF0D95,
        0x7139A801, 0xDE080CB3, 0x9CD8B4E4, 0x906456C1, 0x617BCB84, 0x70D532B6, 0x74486C5C, 0x42D0B857
    );

    /**
     * Precomputed invMixColumns table
     *
     * @see Crypt_Rijndael:_encryptBlock()
     * @see Crypt_Rijndael:_decryptBlock()
     * @var Array
     * @access private
     */
    var $dt2 = array(
        0xA75051F4, 0x65537E41, 0xA4C31A17, 0x5E963A27, 0x6BCB3BAB, 0x45F11F9D, 0x58ABACFA, 0x03934BE3,
        0xFA552030, 0x6DF6AD76, 0x769188CC, 0x4C25F502, 0xD7FC4FE5, 0xCBD7C52A, 0x44802635, 0xA38FB562,
        0x5A49DEB1, 0x1B6725BA, 0x0E9845EA, 0xC0E15DFE, 0x7502C32F, 0xF012814C, 0x97A38D46, 0xF9C66BD3,
        0x5FE7038F, 0x9C951592, 0x7AEBBF6D, 0x59DA9552, 0x832DD4BE, 0x21D35874, 0x692949E0, 0xC8448EC9,
        0x896A75C2, 0x7978F48E, 0x3E6B9958, 0x71DD27B9, 0x4FB6BEE1, 0xAD17F088, 0xAC66C920, 0x3AB47DCE,
        0x4A1863DF, 0x3182E51A, 0x33609751, 0x7F456253, 0x77E0B164, 0xAE84BB6B, 0xA01CFE81, 0x2B94F908,
        0x68587048, 0xFD198F45, 0x6C8794DE, 0xF8B7527B, 0xD323AB73, 0x02E2724B, 0x8F57E31F, 0xAB2A6655,
        0x2807B2EB, 0xC2032FB5, 0x7B9A86C5, 0x08A5D337, 0x87F23028, 0xA5B223BF, 0x6ABA0203, 0x825CED16,
        0x1C2B8ACF, 0xB492A779, 0xF2F0F307, 0xE2A14E69, 0xF4CD65DA, 0xBED50605, 0x621FD134, 0xFE8AC4A6,
        0x539D342E, 0x55A0A2F3, 0xE132058A, 0xEB75A4F6, 0xEC390B83, 0xEFAA4060, 0x9F065E71, 0x1051BD6E,
        0x8AF93E21, 0x063D96DD, 0x05AEDD3E, 0xBD464DE6, 0x8DB59154, 0x5D0571C4, 0xD46F0406, 0x15FF6050,
        0xFB241998, 0xE997D6BD, 0x43CC8940, 0x9E7767D9, 0x42BDB0E8, 0x8B880789, 0x5B38E719, 0xEEDB79C8,
        0x0A47A17C, 0x0FE97C42, 0x1EC9F884, 0x00000000, 0x86830980, 0xED48322B, 0x70AC1E11, 0x724E6C5A,
        0xFFFBFD0E, 0x38560F85, 0xD51E3DAE, 0x3927362D, 0xD9640A0F, 0xA621685C, 0x54D19B5B, 0x2E3A2436,
        0x67B10C0A, 0xE70F9357, 0x96D2B4EE, 0x919E1B9B, 0xC54F80C0, 0x20A261DC, 0x4B695A77, 0x1A161C12,
        0xBA0AE293, 0x2AE5C0A0, 0xE0433C22, 0x171D121B, 0x0D0B0E09, 0xC7ADF28B, 0xA8B92DB6, 0xA9C8141E,
        0x198557F1, 0x074CAF75, 0xDDBBEE99, 0x60FDA37F, 0x269FF701, 0xF5BC5C72, 0x3BC54466, 0x7E345BFB,
        0x29768B43, 0xC6DCCB23, 0xFC68B6ED, 0xF163B8E4, 0xDCCAD731, 0x85104263, 0x22401397, 0x112084C6,
        0x247D854A, 0x3DF8D2BB, 0x3211AEF9, 0xA16DC729, 0x2F4B1D9E, 0x30F3DCB2, 0x52EC0D86, 0xE3D077C1,
        0x166C2BB3, 0xB999A970, 0x48FA1194, 0x642247E9, 0x8CC4A8FC, 0x3F1AA0F0, 0x2CD8567D, 0x90EF2233,
        0x4EC78749, 0xD1C1D938, 0xA2FE8CCA, 0x0B3698D4, 0x81CFA6F5, 0xDE28A57A, 0x8E26DAB7, 0xBFA43FAD,
        0x9DE42C3A, 0x920D5078, 0xCC9B6A5F, 0x4662547E, 0x13C2F68D, 0xB8E890D8, 0xF75E2E39, 0xAFF582C3,
        0x80BE9F5D, 0x937C69D0, 0x2DA96FD5, 0x12B3CF25, 0x993BC8AC, 0x7DA71018, 0x636EE89C, 0xBB7BDB3B,
        0x7809CD26, 0x18F46E59, 0xB701EC9A, 0x9AA8834F, 0x6E65E695, 0xE67EAAFF, 0xCF0821BC, 0xE8E6EF15,
        0x9BD9BAE7, 0x36CE4A6F, 0x09D4EA9F, 0x7CD629B0, 0xB2AF31A4, 0x23312A3F, 0x9430C6A5, 0x66C035A2,
        0xBC37744E, 0xCAA6FC82, 0xD0B0E090, 0xD81533A7, 0x984AF104, 0xDAF741EC, 0x500E7FCD, 0xF62F1791,
        0xD68D764D, 0xB04D43EF, 0x4D54CCAA, 0x04DFE496, 0xB5E39ED1, 0x881B4C6A, 0x1FB8C12C, 0x517F4665,
        0xEA049D5E, 0x355D018C, 0x7473FA87, 0x412EFB0B, 0x1D5AB367, 0xD25292DB, 0x5633E910, 0x47136DD6,
        0x618C9AD7, 0x0C7A37A1, 0x148E59F8, 0x3C89EB13, 0x27EECEA9, 0xC935B761, 0xE5EDE11C, 0xB13C7A47,
        0xDF599CD2, 0x733F55F2, 0xCE791814, 0x37BF73C7, 0xCDEA53F7, 0xAA5B5FFD, 0x6F14DF3D, 0xDB867844,
        0xF381CAAF, 0xC43EB968, 0x342C3824, 0x405FC2A3, 0xC372161D, 0x250CBCE2, 0x498B283C, 0x9541FF0D,
        0x017139A8, 0xB3DE080C, 0xE49CD8B4, 0xC1906456, 0x84617BCB, 0xB670D532, 0x5C74486C, 0x5742D0B8
    );

    /**
     * Precomputed invMixColumns table
     *
     * @see Crypt_Rijndael:_encryptBlock()
     * @see Crypt_Rijndael:_decryptBlock()
     * @var Array
     * @access private
     */
    var $dt3 = array(
        0xF4A75051, 0x4165537E, 0x17A4C31A, 0x275E963A, 0xAB6BCB3B, 0x9D45F11F, 0xFA58ABAC, 0xE303934B,
        0x30FA5520, 0x766DF6AD, 0xCC769188, 0x024C25F5, 0xE5D7FC4F, 0x2ACBD7C5, 0x35448026, 0x62A38FB5,
        0xB15A49DE, 0xBA1B6725, 0xEA0E9845, 0xFEC0E15D, 0x2F7502C3, 0x4CF01281, 0x4697A38D, 0xD3F9C66B,
        0x8F5FE703, 0x929C9515, 0x6D7AEBBF, 0x5259DA95, 0xBE832DD4, 0x7421D358, 0xE0692949, 0xC9C8448E,
        0xC2896A75, 0x8E7978F4, 0x583E6B99, 0xB971DD27, 0xE14FB6BE, 0x88AD17F0, 0x20AC66C9, 0xCE3AB47D,
        0xDF4A1863, 0x1A3182E5, 0x51336097, 0x537F4562, 0x6477E0B1, 0x6BAE84BB, 0x81A01CFE, 0x082B94F9,
        0x48685870, 0x45FD198F, 0xDE6C8794, 0x7BF8B752, 0x73D323AB, 0x4B02E272, 0x1F8F57E3, 0x55AB2A66,
        0xEB2807B2, 0xB5C2032F, 0xC57B9A86, 0x3708A5D3, 0x2887F230, 0xBFA5B223, 0x036ABA02, 0x16825CED,
        0xCF1C2B8A, 0x79B492A7, 0x07F2F0F3, 0x69E2A14E, 0xDAF4CD65, 0x05BED506, 0x34621FD1, 0xA6FE8AC4,
        0x2E539D34, 0xF355A0A2, 0x8AE13205, 0xF6EB75A4, 0x83EC390B, 0x60EFAA40, 0x719F065E, 0x6E1051BD,
        0x218AF93E, 0xDD063D96, 0x3E05AEDD, 0xE6BD464D, 0x548DB591, 0xC45D0571, 0x06D46F04, 0x5015FF60,
        0x98FB2419, 0xBDE997D6, 0x4043CC89, 0xD99E7767, 0xE842BDB0, 0x898B8807, 0x195B38E7, 0xC8EEDB79,
        0x7C0A47A1, 0x420FE97C, 0x841EC9F8, 0x00000000, 0x80868309, 0x2BED4832, 0x1170AC1E, 0x5A724E6C,
        0x0EFFFBFD, 0x8538560F, 0xAED51E3D, 0x2D392736, 0x0FD9640A, 0x5CA62168, 0x5B54D19B, 0x362E3A24,
        0x0A67B10C, 0x57E70F93, 0xEE96D2B4, 0x9B919E1B, 0xC0C54F80, 0xDC20A261, 0x774B695A, 0x121A161C,
        0x93BA0AE2, 0xA02AE5C0, 0x22E0433C, 0x1B171D12, 0x090D0B0E, 0x8BC7ADF2, 0xB6A8B92D, 0x1EA9C814,
        0xF1198557, 0x75074CAF, 0x99DDBBEE, 0x7F60FDA3, 0x01269FF7, 0x72F5BC5C, 0x663BC544, 0xFB7E345B,
        0x4329768B, 0x23C6DCCB, 0xEDFC68B6, 0xE4F163B8, 0x31DCCAD7, 0x63851042, 0x97224013, 0xC6112084,
        0x4A247D85, 0xBB3DF8D2, 0xF93211AE, 0x29A16DC7, 0x9E2F4B1D, 0xB230F3DC, 0x8652EC0D, 0xC1E3D077,
        0xB3166C2B, 0x70B999A9, 0x9448FA11, 0xE9642247, 0xFC8CC4A8, 0xF03F1AA0, 0x7D2CD856, 0x3390EF22,
        0x494EC787, 0x38D1C1D9, 0xCAA2FE8C, 0xD40B3698, 0xF581CFA6, 0x7ADE28A5, 0xB78E26DA, 0xADBFA43F,
        0x3A9DE42C, 0x78920D50, 0x5FCC9B6A, 0x7E466254, 0x8D13C2F6, 0xD8B8E890, 0x39F75E2E, 0xC3AFF582,
        0x5D80BE9F, 0xD0937C69, 0xD52DA96F, 0x2512B3CF, 0xAC993BC8, 0x187DA710, 0x9C636EE8, 0x3BBB7BDB,
        0x267809CD, 0x5918F46E, 0x9AB701EC, 0x4F9AA883, 0x956E65E6, 0xFFE67EAA, 0xBCCF0821, 0x15E8E6EF,
        0xE79BD9BA, 0x6F36CE4A, 0x9F09D4EA, 0xB07CD629, 0xA4B2AF31, 0x3F23312A, 0xA59430C6, 0xA266C035,
        0x4EBC3774, 0x82CAA6FC, 0x90D0B0E0, 0xA7D81533, 0x04984AF1, 0xECDAF741, 0xCD500E7F, 0x91F62F17,
        0x4DD68D76, 0xEFB04D43, 0xAA4D54CC, 0x9604DFE4, 0xD1B5E39E, 0x6A881B4C, 0x2C1FB8C1, 0x65517F46,
        0x5EEA049D, 0x8C355D01, 0x877473FA, 0x0B412EFB, 0x671D5AB3, 0xDBD25292, 0x105633E9, 0xD647136D,
        0xD7618C9A, 0xA10C7A37, 0xF8148E59, 0x133C89EB, 0xA927EECE, 0x61C935B7, 0x1CE5EDE1, 0x47B13C7A,
        0xD2DF599C, 0xF2733F55, 0x14CE7918, 0xC737BF73, 0xF7CDEA53, 0xFDAA5B5F, 0x3D6F14DF, 0x44DB8678,
        0xAFF381CA, 0x68C43EB9, 0x24342C38, 0xA3405FC2, 0x1DC37216, 0xE2250CBC, 0x3C498B28, 0x0D9541FF,
        0xA8017139, 0x0CB3DE08, 0xB4E49CD8, 0x56C19064, 0xCB84617B, 0x32B670D5, 0x6C5C7448, 0xB85742D0
    );

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

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

    /**
     * Sets the key.
     *
     * Keys can be of any length.  Rijndael, itself, requires the use of a key that's between 128-bits and 256-bits long and
     * whose length is a multiple of 32.  If the key is less than 256-bits and the key length isn't set, we round the length
     * up to the closest valid key length, padding $key with null bytes.  If the key is more than 256-bits, we trim the
     * excess bits.
     *
     * If the key is not explicitly set, it'll be assumed to be all null bytes.
     *
     * Note: 160/224-bit keys must explicitly set by setKeyLength(), otherwise they will be round/pad up to 192/256 bits.
     *
     * @see Crypt_Base:setKey()
     * @see setKeyLength()
     * @access public
     * @param String $key
     */
    function setKey($key)
    {
        parent::setKey($key);

        if (!$this->explicit_key_length) {
            $length = strlen($key);
            switch (true) {
                case $length <= 16:
                    $this->key_size = 16;
                    break;
                case $length <= 20:
                    $this->key_size = 20;
                    break;
                case $length <= 24:
                    $this->key_size = 24;
                    break;
                case $length <= 28:
                    $this->key_size = 28;
                    break;
                default:
                    $this->key_size = 32;
            }
            $this->_setupEngine();
        }
    }

    /**
     * Sets the key length
     *
     * Valid key lengths are 128, 160, 192, 224, and 256.  If the length is less than 128, it will be rounded up to
     * 128.  If the length is greater than 128 and invalid, it will be rounded down to the closest valid amount.
     *
     * Note: phpseclib extends Rijndael (and AES) for using 160- and 224-bit keys but they are officially not defined
     *       and the most (if not all) implementations are not able using 160/224-bit keys but round/pad them up to
     *       192/256 bits as, for example, mcrypt will do.
     *
     *       That said, if you want be compatible with other Rijndael and AES implementations,
     *       you should not setKeyLength(160) or setKeyLength(224).
     *
     * Additional: In case of 160- and 224-bit keys, phpseclib will/can, for that reason, not use
     *             the mcrypt php extension, even if available.
     *             This results then in slower encryption.
     *
     * @access public
     * @param Integer $length
     */
    function setKeyLength($length)
    {
        switch (true) {
            case $length == 160:
                $this->key_size = 20;
                break;
            case $length == 224:
                $this->key_size = 28;
                break;
            case $length <= 128:
                $this->key_size = 16;
                break;
            case $length <= 192:
                $this->key_size = 24;
                break;
            default:
                $this->key_size = 32;
        }

        $this->explicit_key_length = true;
        $this->changed = true;
        $this->_setupEngine();
    }

    /**
     * Sets the block length
     *
     * Valid block lengths are 128, 160, 192, 224, and 256.  If the length is less than 128, it will be rounded up to
     * 128.  If the length is greater than 128 and invalid, it will be rounded down to the closest valid amount.
     *
     * @access public
     * @param Integer $length
     */
    function setBlockLength($length)
    {
        $length >>= 5;
        if ($length > 8) {
            $length = 8;
        } else if ($length < 4) {
            $length = 4;
        }
        $this->Nb = $length;
        $this->block_size = $length << 2;
        $this->changed = true;
        $this->_setupEngine();
    }

    /**
     * Setup the fastest possible $engine
     *
     * Determines if the mcrypt (MODE_MCRYPT) $engine available
     * and usable for the current $block_size and $key_size.
     *
     * If not, the slower MODE_INTERNAL $engine will be set.
     *
     * @see setKey()
     * @see setKeyLength()
     * @see setBlockLength()
     * @access private
     */
    function _setupEngine()
    {
        if (constant('CRYPT_' . $this->const_namespace . '_MODE') == CRYPT_MODE_INTERNAL) {
            // No mcrypt support at all for rijndael
            return;
        }

        // The required mcrypt module name for the current $block_size of rijndael
        $cipher_name_mcrypt = 'rijndael-' . ($this->block_size << 3);

        // Determining the availibility/usability of $cipher_name_mcrypt
        switch (true) {
            case $this->key_size % 8: // mcrypt is not usable for 160/224-bit keys, only for 128/192/256-bit keys
            case !in_array($cipher_name_mcrypt, mcrypt_list_algorithms()): // $cipher_name_mcrypt is not available for the current $block_size
                $engine = CRYPT_MODE_INTERNAL;
                break;
            default:
                $engine = CRYPT_MODE_MCRYPT;
        }

        if ($this->engine == $engine && $this->cipher_name_mcrypt == $cipher_name_mcrypt) {
            // allready set, so we not unnecessary close $this->enmcrypt/demcrypt/ecb
            return;
        }

        // Set the $engine
        $this->engine = $engine;
        $this->cipher_name_mcrypt = $cipher_name_mcrypt;

        if ($this->enmcrypt) {
            // Closing the current mcrypt resource(s). _mcryptSetup() will, if needed,
            // (re)open them with the module named in $this->cipher_name_mcrypt
            mcrypt_module_close($this->enmcrypt);
            mcrypt_module_close($this->demcrypt);
            $this->enmcrypt = null;
            $this->demcrypt = null;

            if ($this->ecb) {
                mcrypt_module_close($this->ecb);
                $this->ecb = null;
            }
        }
    }

    /**
     * Setup the CRYPT_MODE_MCRYPT $engine
     *
     * @see Crypt_Base::_setupMcrypt()
     * @access private
     */
    function _setupMcrypt()
    {
        $this->key = str_pad(substr($this->key, 0, $this->key_size), $this->key_size, "\0");
        parent::_setupMcrypt();
    }

    /**
     * Encrypts a block
     *
     * @access private
     * @param String $in
     * @return String
     */
    function _encryptBlock($in)
    {
        static $t0, $t1, $t2, $t3, $sbox;
        if (!$t0) {
            for ($i = 0; $i < 256; ++$i) {
                $t0[] = (int)$this->t0[$i];
                $t1[] = (int)$this->t1[$i];
                $t2[] = (int)$this->t2[$i];
                $t3[] = (int)$this->t3[$i];
                $sbox[] = (int)$this->sbox[$i];
            }
        }

        $state = array();
        $words = unpack('N*', $in);

        $c = $this->c;
        $w = $this->w;
        $Nb = $this->Nb;
        $Nr = $this->Nr;

        // addRoundKey
        $i = -1;
        foreach ($words as $word) {
            $state[] = $word ^ $w[0][++$i];
        }

        // fips-197.pdf#page=19, "Figure 5. Pseudo Code for the Cipher", states that this loop has four components -
        // subBytes, shiftRows, mixColumns, and addRoundKey. fips-197.pdf#page=30, "Implementation Suggestions Regarding
        // Various Platforms" suggests that performs enhanced implementations are described in Rijndael-ammended.pdf.
        // Rijndael-ammended.pdf#page=20, "Implementation aspects / 32-bit processor", discusses such an optimization.
        // Unfortunately, the description given there is not quite correct.  Per aes.spec.v316.pdf#page=19 [1],
        // equation (7.4.7) is supposed to use addition instead of subtraction, so we'll do that here, as well.

        // [1] http://fp.gladman.plus.com/cryptography_technology/rijndael/aes.spec.v316.pdf
        $temp = array();
        for ($round = 1; $round < $Nr; ++$round) {
            $i = 0; // $c[0] == 0
            $j = $c[1];
            $k = $c[2];
            $l = $c[3];

            while ($i < $Nb) {
                $temp[$i] = $t0[$state[$i] >> 24 & 0x000000FF] ^
                            $t1[$state[$j] >> 16 & 0x000000FF] ^
                            $t2[$state[$k] >>  8 & 0x000000FF] ^
                            $t3[$state[$l]       & 0x000000FF] ^
                            $w[$round][$i];
                ++$i;
                $j = ($j + 1) % $Nb;
                $k = ($k + 1) % $Nb;
                $l = ($l + 1) % $Nb;
            }
            $state = $temp;
        }

        // subWord
        for ($i = 0; $i < $Nb; ++$i) {
            $state[$i] =   $sbox[$state[$i]       & 0x000000FF]        |
                          ($sbox[$state[$i] >>  8 & 0x000000FF] <<  8) |
                          ($sbox[$state[$i] >> 16 & 0x000000FF] << 16) |
                          ($sbox[$state[$i] >> 24 & 0x000000FF] << 24);
        }

        // shiftRows + addRoundKey
        $i = 0; // $c[0] == 0
        $j = $c[1];
        $k = $c[2];
        $l = $c[3];
        while ($i < $Nb) {
            $temp[$i] = ($state[$i] & 0xFF000000) ^
                        ($state[$j] & 0x00FF0000) ^
                        ($state[$k] & 0x0000FF00) ^
                        ($state[$l] & 0x000000FF) ^
                         $w[$Nr][$i];
            ++$i;
            $j = ($j + 1) % $Nb;
            $k = ($k + 1) % $Nb;
            $l = ($l + 1) % $Nb;
        }

        switch ($Nb) {
            case 8:
                return pack('N*', $temp[0], $temp[1], $temp[2], $temp[3], $temp[4], $temp[5], $temp[6], $temp[7]);
            case 7:
                return pack('N*', $temp[0], $temp[1], $temp[2], $temp[3], $temp[4], $temp[5], $temp[6]);
            case 6:
                return pack('N*', $temp[0], $temp[1], $temp[2], $temp[3], $temp[4], $temp[5]);
            case 5:
                return pack('N*', $temp[0], $temp[1], $temp[2], $temp[3], $temp[4]);
            default:
                return pack('N*', $temp[0], $temp[1], $temp[2], $temp[3]);
        }
    }

    /**
     * Decrypts a block
     *
     * @access private
     * @param String $in
     * @return String
     */
    function _decryptBlock($in)
    {
        static $dt0, $dt1, $dt2, $dt3, $isbox;
        if (!$dt0) {
            for ($i = 0; $i < 256; ++$i) {
                $dt0[] = (int)$this->dt0[$i];
                $dt1[] = (int)$this->dt1[$i];
                $dt2[] = (int)$this->dt2[$i];
                $dt3[] = (int)$this->dt3[$i];
                $isbox[] = (int)$this->isbox[$i];
            }
        }

        $state = array();
        $words = unpack('N*', $in);

        $c  = $this->c;
        $dw = $this->dw;
        $Nb = $this->Nb;
        $Nr = $this->Nr;

        // addRoundKey
        $i = -1;
        foreach ($words as $word) {
            $state[] = $word ^ $dw[$Nr][++$i];
        }

        $temp = array();
        for ($round = $Nr - 1; $round > 0; --$round) {
            $i = 0; // $c[0] == 0
            $j = $Nb - $c[1];
            $k = $Nb - $c[2];
            $l = $Nb - $c[3];

            while ($i < $Nb) {
                $temp[$i] = $dt0[$state[$i] >> 24 & 0x000000FF] ^
                            $dt1[$state[$j] >> 16 & 0x000000FF] ^
                            $dt2[$state[$k] >>  8 & 0x000000FF] ^
                            $dt3[$state[$l]       & 0x000000FF] ^
                            $dw[$round][$i];
                ++$i;
                $j = ($j + 1) % $Nb;
                $k = ($k + 1) % $Nb;
                $l = ($l + 1) % $Nb;
            }
            $state = $temp;
        }

        // invShiftRows + invSubWord + addRoundKey
        $i = 0; // $c[0] == 0
        $j = $Nb - $c[1];
        $k = $Nb - $c[2];
        $l = $Nb - $c[3];

        while ($i < $Nb) {
            $word = ($state[$i] & 0xFF000000) |
                    ($state[$j] & 0x00FF0000) |
                    ($state[$k] & 0x0000FF00) |
                    ($state[$l] & 0x000000FF);

            $temp[$i] = $dw[0][$i] ^ ($isbox[$word       & 0x000000FF]        |
                                     ($isbox[$word >>  8 & 0x000000FF] <<  8) |
                                     ($isbox[$word >> 16 & 0x000000FF] << 16) |
                                     ($isbox[$word >> 24 & 0x000000FF] << 24));
            ++$i;
            $j = ($j + 1) % $Nb;
            $k = ($k + 1) % $Nb;
            $l = ($l + 1) % $Nb;
        }

        switch ($Nb) {
            case 8:
                return pack('N*', $temp[0], $temp[1], $temp[2], $temp[3], $temp[4], $temp[5], $temp[6], $temp[7]);
            case 7:
                return pack('N*', $temp[0], $temp[1], $temp[2], $temp[3], $temp[4], $temp[5], $temp[6]);
            case 6:
                return pack('N*', $temp[0], $temp[1], $temp[2], $temp[3], $temp[4], $temp[5]);
            case 5:
                return pack('N*', $temp[0], $temp[1], $temp[2], $temp[3], $temp[4]);
            default:
                return pack('N*', $temp[0], $temp[1], $temp[2], $temp[3]);
        }
    }

    /**
     * Setup the key (expansion)
     *
     * @see Crypt_Base::_setupKey()
     * @access private
     */
    function _setupKey()
    {
        // Each number in $rcon is equal to the previous number multiplied by two in Rijndael's finite field.
        // See http://en.wikipedia.org/wiki/Finite_field_arithmetic#Multiplicative_inverse
        static $rcon = array(0,
            0x01000000, 0x02000000, 0x04000000, 0x08000000, 0x10000000,
            0x20000000, 0x40000000, 0x80000000, 0x1B000000, 0x36000000,
            0x6C000000, 0xD8000000, 0xAB000000, 0x4D000000, 0x9A000000,
            0x2F000000, 0x5E000000, 0xBC000000, 0x63000000, 0xC6000000,
            0x97000000, 0x35000000, 0x6A000000, 0xD4000000, 0xB3000000,
            0x7D000000, 0xFA000000, 0xEF000000, 0xC5000000, 0x91000000
        );

        $this->key = str_pad(substr($this->key, 0, $this->key_size), $this->key_size, "\0");

        if (isset($this->kl['key']) && $this->key === $this->kl['key'] && $this->key_size === $this->kl['key_size'] && $this->block_size === $this->kl['block_size']) {
            // already expanded
            return;
        }
        $this->kl = array('key' => $this->key, 'key_size' => $this->key_size, 'block_size' => $this->block_size);

        $this->Nk = $this->key_size >> 2;
        // see Rijndael-ammended.pdf#page=44
        $this->Nr = max($this->Nk, $this->Nb) + 6;

        // shift offsets for Nb = 5, 7 are defined in Rijndael-ammended.pdf#page=44,
        //     "Table 8: Shift offsets in Shiftrow for the alternative block lengths"
        // shift offsets for Nb = 4, 6, 8 are defined in Rijndael-ammended.pdf#page=14,
        //     "Table 2: Shift offsets for different block lengths"
        switch ($this->Nb) {
            case 4:
            case 5:
            case 6:
                $this->c = array(0, 1, 2, 3);
                break;
            case 7:
                $this->c = array(0, 1, 2, 4);
                break;
            case 8:
                $this->c = array(0, 1, 3, 4);
        }

        $w = array_values(unpack('N*words', $this->key));

        $length = $this->Nb * ($this->Nr + 1);
        for ($i = $this->Nk; $i < $length; $i++) {
            $temp = $w[$i - 1];
            if ($i % $this->Nk == 0) {
                // according to <http://php.net/language.types.integer>, "the size of an integer is platform-dependent".
                // on a 32-bit machine, it's 32-bits, and on a 64-bit machine, it's 64-bits. on a 32-bit machine,
                // 0xFFFFFFFF << 8 == 0xFFFFFF00, but on a 64-bit machine, it equals 0xFFFFFFFF00. as such, doing 'and'
                // with 0xFFFFFFFF (or 0xFFFFFF00) on a 32-bit machine is unnecessary, but on a 64-bit machine, it is.
                $temp = (($temp << 8) & 0xFFFFFF00) | (($temp >> 24) & 0x000000FF); // rotWord
                $temp = $this->_subWord($temp) ^ $rcon[$i / $this->Nk];
            } else if ($this->Nk > 6 && $i % $this->Nk == 4) {
                $temp = $this->_subWord($temp);
            }
            $w[$i] = $w[$i - $this->Nk] ^ $temp;
        }

        // convert the key schedule from a vector of $Nb * ($Nr + 1) length to a matrix with $Nr + 1 rows and $Nb columns
        // and generate the inverse key schedule.  more specifically,
        // according to <http://csrc.nist.gov/archive/aes/rijndael/Rijndael-ammended.pdf#page=23> (section 5.3.3),
        // "The key expansion for the Inverse Cipher is defined as follows:
        //        1. Apply the Key Expansion.
        //        2. Apply InvMixColumn to all Round Keys except the first and the last one."
        // also, see fips-197.pdf#page=27, "5.3.5 Equivalent Inverse Cipher"
        $temp = $this->w = $this->dw = array();
        for ($i = $row = $col = 0; $i < $length; $i++, $col++) {
            if ($col == $this->Nb) {
                if ($row == 0) {
                    $this->dw[0] = $this->w[0];
                } else {
                    // subWord + invMixColumn + invSubWord = invMixColumn
                    $j = 0;
                    while ($j < $this->Nb) {
                        $dw = $this->_subWord($this->w[$row][$j]);
                        $temp[$j] = $this->dt0[$dw >> 24 & 0x000000FF] ^
                                    $this->dt1[$dw >> 16 & 0x000000FF] ^
                                    $this->dt2[$dw >>  8 & 0x000000FF] ^
                                    $this->dt3[$dw       & 0x000000FF];
                        $j++;
                    }
                    $this->dw[$row] = $temp;
                }

                $col = 0;
                $row++;
            }
            $this->w[$row][$col] = $w[$i];
        }

        $this->dw[$row] = $this->w[$row];

        // In case of $this->use_inline_crypt === true we have to use 1-dim key arrays (both ascending)
        if ($this->use_inline_crypt) {
            $this->dw = array_reverse($this->dw);
            $w  = array_pop($this->w);
            $dw = array_pop($this->dw);
            foreach ($this->w as $r => $wr) {
                foreach ($wr as $c => $wc) {
                    $w[]  = $wc;
                    $dw[] = $this->dw[$r][$c];
                }
            }
            $this->w  = $w;
            $this->dw = $dw;
        }
    }

    /**
     * Performs S-Box substitutions
     *
     * @access private
     * @param Integer $word
     */
    function _subWord($word)
    {
        $sbox = $this->sbox;

        return  $sbox[$word       & 0x000000FF]        |
               ($sbox[$word >>  8 & 0x000000FF] <<  8) |
               ($sbox[$word >> 16 & 0x000000FF] << 16) |
               ($sbox[$word >> 24 & 0x000000FF] << 24);
    }

    /**
     * Setup the performance-optimized function for de/encrypt()
     *
     * @see Crypt_Base::_setupInlineCrypt()
     * @access private
     */
    function _setupInlineCrypt()
    {
        // Note: _setupInlineCrypt() will be called only if $this->changed === true
        // So here we are'nt under the same heavy timing-stress as we are in _de/encryptBlock() or de/encrypt().
        // However...the here generated function- $code, stored as php callback in $this->inline_crypt, must work as fast as even possible.

        $lambda_functions =& Crypt_Rijndael::_getLambdaFunctions();

        // The first 10 generated $lambda_functions will use the key-words hardcoded for better performance.
        // For memory reason we limit those ultra-optimized functions.
        // After that, we use pure (extracted) integer vars for the key-words which is faster than accessing them via array.
        if (count($lambda_functions) < 10) {
            $w  = $this->w;
            $dw = $this->dw;
            $init_encrypt = '';
            $init_decrypt = '';
        } else {
            for ($i = 0, $cw = count($this->w); $i < $cw; ++$i) {
                $w[]  = '$w['  . $i . ']';
                $dw[] = '$dw[' . $i . ']';
            }
            $init_encrypt = '$w = $self->w;';
            $init_decrypt = '$dw = $self->dw;';
        }

        $code_hash = md5(str_pad("Crypt_Rijndael, {$this->mode}, {$this->block_size}, ", 32, "\0") . implode(',', $w));

        if (!isset($lambda_functions[$code_hash])) {
            $Nr = $this->Nr;
            $Nb = $this->Nb;
            $c  = $this->c;

            // Generating encrypt code:
            $init_encrypt.= '
                static $t0, $t1, $t2, $t3, $sbox;
                if (!$t0) {
                    for ($i = 0; $i < 256; ++$i) {
                        $t0[$i]    = (int)$self->t0[$i];
                        $t1[$i]    = (int)$self->t1[$i];
                        $t2[$i]    = (int)$self->t2[$i];
                        $t3[$i]    = (int)$self->t3[$i];
                        $sbox[$i]  = (int)$self->sbox[$i];
                    }
                }
            ';

            $s  = 'e';
            $e  = 's';
            $wc = $Nb - 1;

            // Preround: addRoundKey
            $encrypt_block = '$in = unpack("N*", $in);'."\n";
            for ($i = 0; $i < $Nb; ++$i) {
                $encrypt_block .= '$s'.$i.' = $in['.($i + 1).'] ^ '.$w[++$wc].";\n";
            }

            // Mainrounds: shiftRows + subWord + mixColumns + addRoundKey
            for ($round = 1; $round < $Nr; ++$round) {
                list($s, $e) = array($e, $s);
                for ($i = 0; $i < $Nb; ++$i) {
                    $encrypt_block.=
                        '$'.$e.$i.' =
                        $t0[($'.$s.$i                  .' >> 24) & 0xff] ^
                        $t1[($'.$s.(($i + $c[1]) % $Nb).' >> 16) & 0xff] ^
                        $t2[($'.$s.(($i + $c[2]) % $Nb).' >>  8) & 0xff] ^
                        $t3[ $'.$s.(($i + $c[3]) % $Nb).'        & 0xff] ^
                        '.$w[++$wc].";\n";
                }
            }

            // Finalround: subWord + shiftRows + addRoundKey
            for ($i = 0; $i < $Nb; ++$i) {
                $encrypt_block.=
                    '$'.$e.$i.' =
                     $sbox[ $'.$e.$i.'        & 0xff]        |
                    ($sbox[($'.$e.$i.' >>  8) & 0xff] <<  8) |
                    ($sbox[($'.$e.$i.' >> 16) & 0xff] << 16) |
                    ($sbox[($'.$e.$i.' >> 24) & 0xff] << 24);'."\n";
            }
            $encrypt_block .= '$in = pack("N*"'."\n";
            for ($i = 0; $i < $Nb; ++$i) {
                $encrypt_block.= ',
                    ($'.$e.$i                  .' & 0xFF000000) ^
                    ($'.$e.(($i + $c[1]) % $Nb).' & 0x00FF0000) ^
                    ($'.$e.(($i + $c[2]) % $Nb).' & 0x0000FF00) ^
                    ($'.$e.(($i + $c[3]) % $Nb).' & 0x000000FF) ^
                    '.$w[$i]."\n";
            }
            $encrypt_block .= ');';

            // Generating decrypt code:
            $init_decrypt.= '
                static $dt0, $dt1, $dt2, $dt3, $isbox;
                if (!$dt0) {
                    for ($i = 0; $i < 256; ++$i) {
                        $dt0[$i]   = (int)$self->dt0[$i];
                        $dt1[$i]   = (int)$self->dt1[$i];
                        $dt2[$i]   = (int)$self->dt2[$i];
                        $dt3[$i]   = (int)$self->dt3[$i];
                        $isbox[$i] = (int)$self->isbox[$i];
                    }
                }
            ';

            $s  = 'e';
            $e  = 's';
            $wc = $Nb - 1;

            // Preround: addRoundKey
            $decrypt_block = '$in = unpack("N*", $in);'."\n";
            for ($i = 0; $i < $Nb; ++$i) {
                $decrypt_block .= '$s'.$i.' = $in['.($i + 1).'] ^ '.$dw[++$wc].';'."\n";
            }

            // Mainrounds: shiftRows + subWord + mixColumns + addRoundKey
            for ($round = 1; $round < $Nr; ++$round) {
                list($s, $e) = array($e, $s);
                for ($i = 0; $i < $Nb; ++$i) {
                    $decrypt_block.=
                        '$'.$e.$i.' =
                        $dt0[($'.$s.$i                        .' >> 24) & 0xff] ^
                        $dt1[($'.$s.(($Nb + $i - $c[1]) % $Nb).' >> 16) & 0xff] ^
                        $dt2[($'.$s.(($Nb + $i - $c[2]) % $Nb).' >>  8) & 0xff] ^
                        $dt3[ $'.$s.(($Nb + $i - $c[3]) % $Nb).'        & 0xff] ^
                        '.$dw[++$wc].";\n";
                }
            }

            // Finalround: subWord + shiftRows + addRoundKey
            for ($i = 0; $i < $Nb; ++$i) {
                $decrypt_block.=
                    '$'.$e.$i.' =
                     $isbox[ $'.$e.$i.'        & 0xff]        |
                    ($isbox[($'.$e.$i.' >>  8) & 0xff] <<  8) |
                    ($isbox[($'.$e.$i.' >> 16) & 0xff] << 16) |
                    ($isbox[($'.$e.$i.' >> 24) & 0xff] << 24);'."\n";
            }
            $decrypt_block .= '$in = pack("N*"'."\n";
            for ($i = 0; $i < $Nb; ++$i) {
                $decrypt_block.= ',
                    ($'.$e.$i.                        ' & 0xFF000000) ^
                    ($'.$e.(($Nb + $i - $c[1]) % $Nb).' & 0x00FF0000) ^
                    ($'.$e.(($Nb + $i - $c[2]) % $Nb).' & 0x0000FF00) ^
                    ($'.$e.(($Nb + $i - $c[3]) % $Nb).' & 0x000000FF) ^
                    '.$dw[$i]."\n";
            }
            $decrypt_block .= ');';

            $lambda_functions[$code_hash] = $this->_createInlineCryptFunction(
                array(
                   'init_crypt'    => '',
                   'init_encrypt'  => $init_encrypt,
                   'init_decrypt'  => $init_decrypt,
                   'encrypt_block' => $encrypt_block,
                   'decrypt_block' => $decrypt_block
                )
            );
        }
        $this->inline_crypt = $lambda_functions[$code_hash];
    }
}
