<?php

if (!class_exists('TT_Cipher')) {
    
    class TT_Cipher
    {
        function encrypt($plaintxt, $password, $forcesoftware = FALSE)
        {
            
            // PHP4 compatibility functions
            if (!function_exists('str_split')) {
                function str_split($string, $string_length = 1)
                {
                    if (strlen($string) > $string_length || !$string_length) {
                        do {
                            $c       = strlen($string);
                            $parts[] = substr($string, 0, $string_length);
                            $string  = substr($string, $string_length);
                        } while ($string !== false);
                    } else {
                        $parts = array(
                            $string
                        );
                    }
                    return $parts;
                }
            }
            
            if (!function_exists('hex2bin')) {                

                if (!defined('HEX2BIN_WS')) {
                    define('HEX2BIN_WS', " \t\n\r");                
                }

                function hex2bin($hex_string)
                {
                    $pos    = 0;
                    $result = '';
                    
                    while ($pos < strlen($hex_string)) {
                        if (strpos(HEX2BIN_WS, $hex_string{$pos}) !== FALSE) {
                            $pos++;
                        } else {
                            $code = hexdec(substr($hex_string, $pos, 2));
                            $pos  = $pos + 2;
                            
                            $result .= chr($code);
                        }
                    }
                    return $result;
                }
            }
            
            
            if (!$plaintxt) {
                return null;
            }
            
            // use md5 apikey as the password,  if its not already an md5, then hash it and use it
            $password = pack("H*", md5($password . md5($password)));
            if (strlen($password) != 16)
                return FALSE;
            
            // mcrypt module support
            if (!$forcesoftware & (function_exists("mcrypt_get_iv_size") && function_exists("mcrypt_create_iv") && function_exists("mcrypt_encrypt"))) {
                
                $iv_size = mcrypt_get_iv_size(MCRYPT_RIJNDAEL_128, MCRYPT_MODE_CBC);
                
                $iv = mcrypt_create_iv($iv_size, MCRYPT_RAND);
                
                // PKCS7 padding required
                $padding = $iv_size - (strlen($plaintxt) % $iv_size);
                $plaintxt .= str_repeat(chr($padding), $padding);
                
                // return the IV with the ciphertext for CBC
                $c = mcrypt_encrypt(MCRYPT_RIJNDAEL_128, $password, $plaintxt, MCRYPT_MODE_CBC, $iv);
                
                return base64_encode($iv . $c);
            } else {
                
                $aes = new TT_AES128();
                $key = $aes->makeKey($password);
                
                // PKCS7 padding required
                $padding = 16 - (strlen($plaintxt) % 16);
                $plaintxt .= str_repeat(chr($padding), $padding);
                
                // split plaintext string into blocks
                $plainTextArray = str_split($plaintxt, 16);
                
                $lastIndex = count($plainTextArray) - 1;
                if (strlen($plainTextArray[$lastIndex]) != 16) {
                    
                    for ($i = strlen($plainTextArray[$lastIndex]); $i < 16; $i++) {
                        $plainTextArray[$lastIndex] .= chr(0);
                    }
                    
                }
                $iv = FALSE;
                
                // generate a random seed
                // if ssl libs are available then use them
                if (function_exists('openssl_random_pseudo_bytes')) {
                    $iv = openssl_random_pseudo_bytes(16, $strong);
                }
                
                // fall back to random characters.  generate a large string and salt/hash it.
                if (!$iv) {
                    $iv = "";
                    for ($i = 0; $i < 32; $i++) {
                        $iv .= chr(rand(0, 255));
                    }
                    $iv = pack("H*", md5( md5($iv) . $iv ));
                }
                
                if (!$iv)
                    return FALSE;
                
                $encryptedTextArray = array();
                for ($i = 0; $i < count($plainTextArray); $i++) {
                    
                    if ($i == 0) {
                        $input = $iv ^ $plainTextArray[$i];
                    } else {
                        $input = $encryptedTextArray[$i - 1] ^ $plainTextArray[$i];
                    }
                    
                    $encryptedTextArray[$i] = $aes->blockEncrypt($input, $key);
                    
                } // for
                
                return base64_encode($iv . join("", $encryptedTextArray));
            } // else
            
            return FALSE;
            
        } // function
    }
} // class

/**
 * AES128
 *
 * Cifrado / Descifrado de datos mediante AES 128
 *
 * Autor: José Manuel Busto López
 * Version: 1.1
 * Fecha: 04-05-2007
 * Licencia: Lesser General Public License (LGPL)
 *
 * Copyright (C) 2007  José Manuel Busto López
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * Based on official reference code by Paulo Bareto and Vincent Rijmen
 */

if (!class_exists('TT_AES128')) {
    
    class TT_AES128
    {
        
        /* Defining the S-box */
        
        var $S = array(99, 124, 119, 123, 242, 107, 111, 197, 48, 1, 103, 43, 254, 215, 171, 118, 202, 
        130, 201, 125, 250, 89, 71, 240, 173, 212, 162, 175, 156, 164, 114, 192, 183, 253, 147, 38, 54, 
        63, 247, 204, 52, 165, 229, 241, 113, 216, 49, 21, 4, 199, 35, 195, 24, 150, 5, 154, 7, 18, 128, 
        226, 235, 39, 178, 117, 9, 131, 44, 26, 27, 110, 90, 160, 82, 59, 214, 179, 41, 227, 47, 132, 
        83, 209, 0, 237, 32, 252, 177, 91, 106, 203, 190, 57, 74, 76, 88, 207, 208, 239, 170, 251, 67, 
        77, 51, 133, 69, 249, 2, 127, 80, 60, 159, 168, 81, 163, 64, 143, 146, 157, 56, 245, 188, 182, 
        218, 33, 16, 255, 243, 210, 205, 12, 19, 236, 95, 151, 68, 23, 196, 167, 126, 61, 100, 93, 25, 
        115, 96, 129, 79, 220, 34, 42, 144, 136, 70, 238, 184, 20, 222, 94, 11, 219, 224, 50, 58, 10, 
        73, 6, 36, 92, 194, 211, 172, 98, 145, 149, 228, 121, 231, 200, 55, 109, 141, 213, 78, 169, 108, 
        86, 244, 234, 101, 122, 174, 8, 186, 120, 37, 46, 28, 166, 180, 198, 232, 221, 116, 31, 75, 189, 
        139, 138, 112, 62, 181, 102, 72, 3, 246, 14, 97, 53, 87, 185, 134, 193, 29, 158, 225, 248, 152, 
        17, 105, 217, 142, 148, 155, 30, 135, 233, 206, 85, 40, 223, 140, 161, 137, 13, 191, 230, 66, 
        104, 65, 153, 45, 15, 176, 84, 187, 22);
        
        /* Defining the S-box inverse (for decryption) */
        var $Si = array(82, 9, 106, 213, 48, 54, 165, 56, 191, 64, 163, 158, 129, 243, 215, 251, 124, 
        227, 57, 130, 155, 47, 255, 135, 52, 142, 67, 68, 196, 222, 233, 203, 84, 123, 148, 50, 166, 
        194, 35, 61, 238, 76, 149, 11, 66, 250, 195, 78, 8, 46, 161, 102, 40, 217, 36, 178, 118, 91, 
        162, 73, 109, 139, 209, 37, 114, 248, 246, 100, 134, 104, 152, 22, 212, 164, 92, 204, 93, 101, 
        182, 146, 108, 112, 72, 80, 253, 237, 185, 218, 94, 21, 70, 87, 167, 141, 157, 132, 144, 216, 
        171, 0, 140, 188, 211, 10, 247, 228, 88, 5, 184, 179, 69, 6, 208, 44, 30, 143, 202, 63, 15, 2, 
        193, 175, 189, 3, 1, 19, 138, 107, 58, 145, 17, 65, 79, 103, 220, 234, 151, 242, 207, 206, 240, 
        180, 230, 115, 150, 172, 116, 34, 231, 173, 53, 133, 226, 249, 55, 232, 28, 117, 223, 110, 71, 
        241, 26, 113, 29, 41, 197, 137, 111, 183, 98, 14, 170, 24, 190, 27, 252, 86, 62, 75, 198, 210, 
        121, 32, 154, 219, 192, 254, 120, 205, 90, 244, 31, 221, 168, 51, 136, 7, 199, 49, 177, 18, 16, 
        89, 39, 128, 236, 95, 96, 81, 127, 169, 25, 181, 74, 13, 45, 229, 122, 159, 147, 201, 156, 239, 
        160, 224, 59, 77, 174, 42, 245, 176, 200, 235, 187, 60, 131, 83, 153, 97, 23, 43, 4, 126, 186, 
        119, 214, 38, 225, 105, 20, 99, 85, 33, 12, 125);
        
        /* Definition of function values rcon */
        var $rcon = array(0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 
        0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91);
        
        /*Definition of 0x02*state[i][j] in GF(2^8) (for MixColumns)*/
        var $T2 = array(0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38,
        40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76, 78, 80, 82, 84,
        86, 88, 90, 92, 94, 96, 98, 100, 102, 104, 106, 108, 110, 112, 114, 116, 118, 120, 122, 124,
        126, 128, 130, 132, 134, 136, 138, 140, 142, 144, 146, 148, 150, 152, 154, 156, 158, 160, 
        162, 164, 166, 168, 170, 172, 174, 176, 178, 180, 182, 184, 186, 188, 190, 192, 194, 196, 
        198, 200, 202, 204, 206, 208, 210, 212, 214, 216, 218, 220, 222, 224, 226, 228, 230, 232, 
        234, 236, 238, 240, 242, 244, 246, 248, 250, 252, 254, 27, 25, 31, 29, 19, 17, 23, 21, 11, 
        9, 15, 13, 3, 1, 7, 5, 59, 57, 63, 61, 51, 49, 55, 53, 43, 41, 47, 45, 35, 33, 39, 37, 91,
        89, 95, 93, 83, 81, 87, 85, 75, 73, 79, 77, 67, 65, 71, 69, 123, 121, 127, 125, 115, 113, 
        119, 117, 107, 105, 111, 109, 99, 97, 103, 101, 155, 153, 159, 157, 147, 145, 151, 149, 
        139, 137, 143, 141, 131, 129, 135, 133, 187, 185, 191, 189, 179, 177, 183, 181, 171, 169, 
        175, 173, 163, 161, 167, 165, 219, 217, 223, 221, 211, 209, 215, 213, 203, 201, 207, 205, 
        195, 193, 199, 197, 251, 249, 255, 253, 243, 241, 247, 245, 235, 233, 239, 237, 227, 225, 
        231, 229);
        
        /*Definition of 0x03*state[i][j] in GF(2^8) (for MixColumns)*/
        var $T3 = array(0, 3, 6, 5, 12, 15, 10, 9, 24, 27, 30, 29, 20, 23, 18, 17, 48, 51, 54, 53, 60,
        63, 58, 57, 40, 43, 46, 45, 36, 39, 34, 33, 96, 99, 102, 101, 108, 111, 106, 105, 120, 123, 
        126, 125, 116, 119, 114, 113, 80, 83, 86, 85, 92, 95, 90, 89, 72, 75, 78, 77, 68, 71, 66, 65,
        192, 195, 198, 197, 204, 207, 202, 201, 216, 219, 222, 221, 212, 215, 210, 209, 240, 243, 246,
        245, 252, 255, 250, 249, 232, 235, 238, 237, 228, 231, 226, 225, 160, 163, 166, 165, 172, 175,
        170, 169, 184, 187, 190, 189, 180, 183, 178, 177, 144, 147, 150, 149, 156, 159, 154, 153, 
        136, 139, 142, 141, 132, 135, 130, 129, 155, 152, 157, 158, 151, 148, 145, 146, 131, 128, 
        133, 134, 143, 140, 137, 138, 171, 168, 173, 174, 167, 164, 161, 162, 179, 176, 181, 182, 
        191, 188, 185, 186, 251, 248, 253, 254, 247, 244, 241, 242, 227, 224, 229, 230, 239, 236, 
        233, 234, 203, 200, 205, 206, 199, 196, 193, 194, 211, 208, 213, 214, 223, 220, 217, 218,
        91, 88, 93, 94, 87, 84, 81, 82, 67, 64, 69, 70, 79, 76, 73, 74, 107, 104, 109, 110, 103,
        100, 97, 98, 115, 112, 117, 118, 127, 124, 121, 122, 59, 56, 61, 62, 55, 52, 49, 50, 35,
        32, 37, 38, 47, 44, 41, 42, 11, 8, 13, 14, 7, 4, 1, 2, 19, 16, 21, 22, 31, 28, 25, 26);
        
        /*Definition of 0x09*state[i][j] in GF(2^8) (for InvMixColumns)*/
        var $T9 = array(0, 9, 18, 27, 36, 45, 54, 63, 72, 65, 90, 83, 108, 101, 126, 119, 144, 
        153, 130, 139, 180, 189, 166, 175, 216, 209, 202, 195, 252, 245, 238, 231, 59, 50, 41, 
        32, 31, 22, 13, 4, 115, 122, 97, 104, 87, 94, 69, 76, 171, 162, 185, 176, 143, 134, 157, 
        148, 227, 234, 241, 248, 199, 206, 213, 220, 118, 127, 100, 109, 82, 91, 64, 73, 62, 55, 
        44, 37, 26, 19, 8, 1, 230, 239, 244, 253, 194, 203, 208, 217, 174, 167, 188, 181, 138, 
        131, 152, 145, 77, 68, 95, 86, 105, 96, 123, 114, 5, 12, 23, 30, 33, 40, 51, 58, 221, 
        212, 207, 198, 249, 240, 235, 226, 149, 156, 135, 142, 177, 184, 163, 170, 236, 229, 
        254, 247, 200, 193, 218, 211, 164, 173, 182, 191, 128, 137, 146, 155, 124, 117, 110, 
        103, 88, 81, 74, 67, 52, 61, 38, 47, 16, 25, 2, 11, 215, 222, 197, 204, 243, 250, 225, 
        232, 159, 150, 141, 132, 187, 178, 169, 160, 71, 78, 85, 92, 99, 106, 113, 120, 15, 6, 
        29, 20, 43, 34, 57, 48, 154, 147, 136, 129, 190, 183, 172, 165, 210, 219, 192, 201, 246, 
        255, 228, 237, 10, 3, 24, 17, 46, 39, 60, 53, 66, 75, 80, 89, 102, 111, 116, 125, 161, 
        168, 179, 186, 133, 140, 151, 158, 233, 224, 251, 242, 205, 196, 223, 214, 49, 56, 35, 
        42, 21, 28, 7, 14, 121, 112, 107, 98, 93, 84, 79, 70);
        
        /*Definition of 0x0b*state[i][j] in GF(2^8)(for InvMixColumns)*/
        var $T11 = array(0, 11, 22, 29, 44, 39, 58, 49, 88, 83, 78, 69, 116, 127, 98, 105, 176, 
        187, 166, 173, 156, 151, 138, 129, 232, 227, 254, 245, 196, 207, 210, 217, 123, 112, 
        109, 102, 87, 92, 65, 74, 35, 40, 53, 62, 15, 4, 25, 18, 203, 192, 221, 214, 231, 236, 
        241, 250, 147, 152, 133, 142, 191, 180, 169, 162, 246, 253, 224, 235, 218, 209, 204, 
        199, 174, 165, 184, 179, 130, 137, 148, 159, 70, 77, 80, 91, 106, 97, 124, 119, 30, 
        21, 8, 3, 50, 57, 36, 47, 141, 134, 155, 144, 161, 170, 183, 188, 213, 222, 195, 200, 
        249, 242, 239, 228, 61, 54, 43, 32, 17, 26, 7, 12, 101, 110, 115, 120, 73, 66, 95, 84, 
        247, 252, 225, 234, 219, 208, 205, 198, 175, 164, 185, 178, 131, 136, 149, 158, 71, 76, 
        81, 90, 107, 96, 125, 118, 31, 20, 9, 2, 51, 56, 37, 46, 140, 135, 154, 145, 160, 171, 
        182, 189, 212, 223, 194, 201, 248, 243, 238, 229, 60, 55, 42, 33, 16, 27, 6, 13, 100, 
        111, 114, 121, 72, 67, 94, 85, 1, 10, 23, 28, 45, 38, 59, 48, 89, 82, 79, 68, 117, 126, 
        99, 104, 177, 186, 167, 172, 157, 150, 139, 128, 233, 226, 255, 244, 197, 206, 211, 216, 
        122, 113, 108, 103, 86, 93, 64, 75, 34, 41, 52, 63, 14, 5, 24, 19, 202, 193, 220, 215, 
        230, 237, 240, 251, 146, 153, 132, 143, 190, 181, 168, 163);
        
        /*Definition of 0x0d*state[i][j] in GF(2^8) (for InvMixColumns)*/
        var $T13 = array(0, 13, 26, 23, 52, 57, 46, 35, 104, 101, 114, 127, 92, 81, 70, 75, 208, 
        221, 202, 199, 228, 233, 254, 243, 184, 181, 162, 175, 140, 129, 150, 155, 187, 182, 161, 
        172, 143, 130, 149, 152, 211, 222, 201, 196, 231, 234, 253, 240, 107, 102, 113, 124, 95, 
        82, 69, 72, 3, 14, 25, 20, 55, 58, 45, 32, 109, 96, 119, 122, 89, 84, 67, 78, 5, 8, 31, 
        18, 49, 60, 43, 38, 189, 176, 167, 170, 137, 132, 147, 158, 213, 216, 207, 194, 225, 236, 
        251, 246, 214, 219, 204, 193, 226, 239, 248, 245, 190, 179, 164, 169, 138, 135, 144, 157, 
        6, 11, 28, 17, 50, 63, 40, 37, 110, 99, 116, 121, 90, 87, 64, 77, 218, 215, 192, 205, 238, 
        227, 244, 249, 178, 191, 168, 165, 134, 139, 156, 145, 10, 7, 16, 29, 62, 51, 36, 41, 98, 
        111, 120, 117, 86, 91, 76, 65, 97, 108, 123, 118, 85, 88, 79, 66, 9, 4, 19, 30, 61, 48, 
        39, 42, 177, 188, 171, 166, 133, 136, 159, 146, 217, 212, 195, 206, 237, 224, 247, 250, 
        183, 186, 173, 160, 131, 142, 153, 148, 223, 210, 197, 200, 235, 230, 241, 252, 103, 106, 
        125, 112, 83, 94, 73, 68, 15, 2, 21, 24, 59, 54, 33, 44, 12, 1, 22, 27, 56, 53, 34, 47, 
        100, 105, 126, 115, 80, 93, 74, 71, 220, 209, 198, 203, 232, 229, 242, 255, 180, 185, 
        174, 163, 128, 141, 154, 151);
        
        /*Definition of 0x0e*state[i][j] in GF(2^8) (for InvMixColumns)*/
        var $T14 = array(0, 14, 28, 18, 56, 54, 36, 42, 112, 126, 108, 98, 72, 70, 84, 90, 224, 
        238, 252, 242, 216, 214, 196, 202, 144, 158, 140, 130, 168, 166, 180, 186, 219, 213, 199, 
        201, 227, 237, 255, 241, 171, 165, 183, 185, 147, 157, 143, 129, 59, 53, 39, 41, 3, 13, 
        31, 17, 75, 69, 87, 89, 115, 125, 111, 97, 173, 163, 177, 191, 149, 155, 137, 135, 221, 
        211, 193, 207, 229, 235, 249, 247, 77, 67, 81, 95, 117, 123, 105, 103, 61, 51, 33, 47, 5, 
        11, 25, 23, 118, 120, 106, 100, 78, 64, 82, 92, 6, 8, 26, 20, 62, 48, 34, 44, 150, 152, 
        138, 132, 174, 160, 178, 188, 230, 232, 250, 244, 222, 208, 194, 204, 65, 79, 93, 83, 121, 
        119, 101, 107, 49, 63, 45, 35, 9, 7, 21, 27, 161, 175, 189, 179, 153, 151, 133, 139, 209, 
        223, 205, 195, 233, 231, 245, 251, 154, 148, 134, 136, 162, 172, 190, 176, 234, 228, 246, 
        248, 210, 220, 206, 192, 122, 116, 102, 104, 66, 76, 94, 80, 10, 4, 22, 24, 50, 60, 46, 
        32, 236, 226, 240, 254, 212, 218, 200, 198, 156, 146, 128, 142, 164, 170, 184, 182, 12, 
        2, 16, 30, 52, 58, 40, 38, 124, 114, 96, 110, 68, 74, 88, 86, 55, 57, 43, 37, 15, 1, 19, 
        29, 71, 73, 91, 85, 127, 113, 99, 109, 215, 217, 203, 197, 239, 225, 243, 253, 167, 169, 
        187, 181, 159, 145, 131, 141);
        
        var $Nr = 10; //Number of founds 128b=>10
        var $Nb = 4; //Number of columns in each state (sample 4)
        var $Nk = 4; //Key length 128b => 4
        
        var $state = array(array());
        var $shifts_r = array(array(0, 1, 2, 3), array(3, 0, 1, 2), array(2, 3, 0, 1), array(1, 2, 3, 0));
        var $shifts_l = array(array(0, 1, 2, 3), array(1, 2, 3, 0), array(2, 3, 0, 1), array(3, 0, 1, 2));
        var $debug = false;
        var $toHex = false;
        
        //////////////////////////////////////////////////////////////////////////////
        // INTERNAL FUNCTIONS
        /////////////////////////////////////////////////////////////////////////////
        
        
        /**
         * Performs an XOR between S-box and key ith rk.
         *
         * @param rk  Array of characters (4x4) with the key i-th
         */
        
        function KeyAddition($rk)
        {
            
            //Para cada found hacemos una XOR entre Sbox[i][j] y rk[round][i][j].
            for ($i = 0; $i < 4; $i++)
                for ($j = 0; $j < $this->Nb; $j++)
                    $this->state[$i][$j] ^= $rk[$i][$j];
        }
        
        
        /*
         * For each we found an XOR between Sbox [i] [j] and rk [round] [i] [j].
         *
         */
        
        function ByteSubShiftRow()
        {
            $tmp = array(
                array()
            );
            
            for ($i = 0; $i < 4; $i++)
                for ($j = 0; $j < $this->Nb; $j++)
                    $tmp[$i][$this->shifts_r[$i][$j]] = $this->S[$this->state[$i][$j]];
            
            $this->state = $tmp;
        }
        
        /**
         * Performs MixColumn () and KeyAddition () as defined in FIPS-198.
         *
         * @param rk  array of characters (4x4) with the key i-th
         */
        function MixColumnKeyAddition($rk)
        {
            $b = array(
                array()
            );
            
            for ($j = 0; $j < 4; $j++)
                for ($i = 0; $i < $this->Nb; $i++) {
                    $b[$i][$j] = $this->T2[$this->state[$i][$j]] ^ $this->T3[$this->state[($i + 1) % 4][$j]] ^ $this->state[($i + 2) % 4][$j] ^ $this->state[($i + 3) % 4][$j];
                    $b[$i][$j] ^= $rk[$i][$j];
                }
            
            $this->state = $b;
        }
        
        /**
         * Performs the inverse function MixColumn ()
         *
         */
        function InvMixColumn()
        {
            $b = array(
                array()
            );
            
            for ($j = 0; $j < 4; $j++)
                for ($i = 0; $i < $this->Nb; $i++)
                    $b[$i][$j] = $this->T14[$this->state[$i][$j]] ^ $this->T11[$this->state[($i + 1) % 4][$j]] ^ $this->T13[$this->state[($i + 2) % 4][$j]] ^ $this->T9[$this->state[($i + 3) % 4][$j]];
            $this->state = $b;
        }
        
        /**
         * Performs the inverse function of SubBytes () and ShiftRow ().
         *
         */
        function InvShiftRowInvByteSub()
        {
            $tmp = array(
                array()
            );
            
            for ($i = 0; $i < 4; $i++)
                for ($j = 0; $j < $this->Nb; $j++)
                    $tmp[$i][$this->shifts_l[$i][$j]] = $this->Si[$this->state[$i][$j]];
            
            $this->state = $tmp;
        }
        
        
        /////////////////////////////////////////////////////////////////////////
        // Encryption functions
        /////////////////////////////////////////////////////////////////////////
        
        /**
         * Constructor
         *
         * @param hex If true returns the values in hexadecimal
         * @param debug If true sample debug information
         */
        function __construct($hex = false, $debug = false)
        {
            $this->debug = $debug;
            $this->toHex = $hex;
        }
        
        /**
         * Create matrix encryption keys.
         *
         * @param key  Encryption key length equal to 16 characters.
         * @return     Array of keys to encrypt / decrypt.
         */
        function makeKey($hash)
        {
            $rconpocharer = 0;
            $tk           = array(
                array()
            );
            ;
            $rk = array(
                array(
                    array()
                )
            );
            for ($j = 0; $j < $this->Nk; $j++)
                for ($i = 0; $i < 4; $i++)
                    $tk[$i][$j] = @ord($hash{$j * 4 + $i}) > 256 ? @ord($hash{$j * 4 + $i}) % 256 : @ord($hash{$j * 4 + $i});
            $t = 0;
            
            for ($j = 0; ($j < $this->Nk) && ($t < ($this->Nr + 1) * $this->Nb); $j++, $t++)
                for ($i = 0; $i < 4; $i++)
                    $rk[$t / $this->Nb][$i][$t % $this->Nb] = $tk[$i][$j];
            while ($t < ($this->Nr + 1) * $this->Nb) {
                
                for ($i = 0; $i < 4; $i++)
                    $tk[$i][0] ^= $this->S[$tk[($i + 1) % 4][$this->Nk - 1]];
                $tk[0][0] ^= $this->rcon[$rconpocharer++];
                for ($j = 1; $j < $this->Nk; $j++)
                    for ($i = 0; $i < 4; $i++) {
                        $tk[$i][$j] ^= $tk[$i][$j - 1];
                    }
                for ($j = 0; ($j < $this->Nk) && ($t < ($this->Nr + 1) * $this->Nb); $j++, $t++)
                    for ($i = 0; $i < 4; $i++) {
                        $rk[$t / $this->Nb][$i][$t % $this->Nb] = $tk[$i][$j];
                    }
            }
            return $rk;
        }
        
        /**
         * Performs encryption 1 data block (128 bits).
         *
         * @param Data in encrypted (length 128 bits).
              * @param Array keyin encryption key (generated with makeKey ())
              * @return The string encrypted data.
         */
        function blockEncrypt($in, $key)
        {
            
            for ($i = 0; $i < 4; $i++) {
                for ($j = 0; $j < $this->Nb; $j++) {
                    $this->state[$j][$i] = ord($in{$i * 4 + $j});
                }
            }
            $this->showInt("Encryption: \b State Inicial");
            $this->KeyAddition($key[0]);
            $this->showInt("Round 0 :: KeyAddition");
            for ($r = 1; $r < $this->Nr; $r++) {
                $this->ByteSubShiftRow();
                $this->showInt("Round $r :: ByteSubShiftRow");
                $this->MixColumnKeyAddition($key[$r]);
                $this->showInt("Round $r :: MixColumnKeyAddition");
            }
            
            $this->ByteSubShiftRow();
            $this->showInt("Round final :: ByteSubShiftRow");
            $this->KeyAddition($key[$this->Nr]);
            $this->showInt("Round final :: KeyAddition ==> Result");
            
            $out = "";
            for ($i = 0; $i < 4; $i++)
                for ($j = 0; $j < 4; $j++)
                    $out .= chr($this->state[$j][$i]);
            
            if ($this->toHex) {
                $out = $this->toHexString($out);
            }
            return $out;
        }
        
        /**
         * Perform decryption 1 data block (128 bits).
               *
               * @param In deciphering data (length 128 bits).
               * @param Array keyin encryption key (generated with makeKey ())
               * @return The decoded data string.    
         */
        function blockDecrypt($in, $key)
        {
            
            for ($i = 0; $i < 4; $i++) {
                for ($j = 0; $j < $this->Nb; $j++) {
                    $this->state[$j][$i] = ord($in{$i * 4 + $j});
                }
            }
            
            $this->showInt("Decoded: \b Initial State");
            $this->KeyAddition($key[$this->Nr]);
            $this->showInt("Round 0 :: KeyAddition");
            
            for ($r = $this->Nr - 1; $r > 0; $r--) {
                $this->InvShiftRowInvByteSub();
                $this->showInt("Round " . ($this->Nr - $r) . " :: InvShiftRowInvByteSub");
                $this->KeyAddition($key[$r]);
                $this->showInt("Round " . ($this->Nr - $r) . " :: KeyAddition");
                $this->InvMixColumn();
                $this->showInt("Round " . ($this->Nr - $r) . " :: InvMiColumn");
            }
            
            $this->InvShiftRowInvByteSub();
            $this->showInt("Round final :: InvShiftRowInvByteSub");
            $this->KeyAddition($key[0]);
            $this->showInt("Round final :: KeyAddition ==> Result");
            
            $out = "";
            for ($i = 0; $i < 4; $i++)
                for ($j = 0; $j < 4; $j++)
                    $out .= chr($this->state[$j][$i]);
            
            if ($this->toHex) {
                $out = $this->toHexString($out);
            }
            
            return $out;
        }
        
        
        
        ////////////////////////////////////////////////////////////////////////
        // Self test functions
        ////////////////////////////////////////////////////////////////////////
        
        /**
         * Perform a self test
         *
         */
        function self_test()
        {
            $hash = "";
            $in   = "";
            for ($i = 0; $i < 16; $i++) {
                $hash .= chr($i);
            }
            $in .= chr(0x00);
            $in .= chr(0x11);
            $in .= chr(0x22);
            $in .= chr(0x33);
            $in .= chr(0x44);
            $in .= chr(0x55);
            $in .= chr(0x66);
            $in .= chr(0x77);
            $in .= chr(0x88);
            $in .= chr(0x99);
            $in .= chr(0xaa);
            $in .= chr(0xbb);
            $in .= chr(0xcc);
            $in .= chr(0xdd);
            $in .= chr(0xee);
            $in .= chr(0xff);
            echo ("===============================\n");
            echo ("KEYSIZE= 128 bits<br/>");
            echo ("KEY= 0x" . $this->toHexString($hash) . "\n");
            echo ("Plaintext= 0x" . $this->toHexString($in) . "\n");
            
            $key = $this->makeKey($hash);
            $ct  = $this->blockEncrypt($in, $key);
            echo ("Ciphertext= 0x" . $this->toHexString($ct) . "\n");
            $cpt = $this->blockDecrypt($ct, $key);
            echo ("Decoded= 0x" . $this->toHexString($cpt) . "\n");
            
            if (!strcmp($cpt, $in)) {
                if (!$this->debug) {
                    $start = microtime(true);
                    for ($i = 0; $i < 1024; $i++) {
                        $cpt = $this->blockEncrypt($ct, $key);
                    }
                    $end = (microtime(true) - $start) * 1000;
                    echo ("Encryption time 16 KB (1024 blocks): " . $end . " ms\n");
                }
                
                echo ("128-bit encryption correct\n");
            } else
                echo ("128-bit encryption failed\n");
        }
        
        ///////////////////////////////////////////////////////////////////////
        // Extra functions
        //////////////////////////////////////////////////////////////////////
        
        function toHexString($sa)
        {
            $buf = "";
            for ($i = 0; $i < strlen($sa); $i++) {
                $val = dechex(ord($sa{$i}));
                if (strlen($val) < 2)
                    $val = "0" . $val;
                $buf .= $val;
            }
            return $buf;
        }
        
        function fromHexString($sa)
        {
            $buf = "";
            for ($i = 0; $i < strlen($sa); $i = $i + 2) {
                $val = chr(hexdec(substr($sa, $i, 2)));
                $buf .= $val;
            }
            return $buf;
        }
        
        
        function showInt($texto)
        {
            if ($this->debug) {
                echo ($texto . ": ");
                for ($i = 0; $i < 4; $i++) {
                    for ($j = 0; $j < 4; $j++) {
                        echo (dechex($this->state[$j][$i]) . " ");
                    }
                }
                echo ("\n");
            }
        }
        
    } // if 
} // class