nilsteampassnet /
TeamPass
| @@ 10-211 (lines=202) @@ | ||
| 7 | /* form is offered. */ |
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| 8 | /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ |
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| 9 | ||
| 10 | class Aes |
|
| 11 | { |
|
| 12 | /** |
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| 13 | * AES Cipher function: encrypt 'input' with Rijndael algorithm |
|
| 14 | * |
|
| 15 | * @param input message as byte-array (16 bytes) |
|
| 16 | * @param w key schedule as 2D byte-array (Nr+1 x Nb bytes) - |
|
| 17 | * generated from the cipher key by keyExpansion() |
|
| 18 | * @return ciphertext as byte-array (16 bytes) |
|
| 19 | */ |
|
| 20 | public static function cipher($input, $w) |
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| 21 | { |
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| 22 | // main cipher function [é5.1] |
|
| 23 | $Nb = 4; // block size (in words): no of columns in state (fixed at 4 for AES) |
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| 24 | $Nr = count($w) / $Nb - 1; // no of rounds: 10/12/14 for 128/192/256-bit keys |
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| 25 | ||
| 26 | $state = array(); // initialise 4xNb byte-array 'state' with input [é3.4] |
|
| 27 | for ($i = 0; $i < 4 * $Nb; $i++) { |
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| 28 | $state[$i % 4][floor($i / 4)] = $input[$i]; |
|
| 29 | } |
|
| 30 | ||
| 31 | $state = self::addRoundKey($state, $w, 0, $Nb); |
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| 32 | ||
| 33 | for ($round = 1; $round < $Nr; $round++) { // apply Nr rounds |
|
| 34 | $state = self::subBytes($state, $Nb); |
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| 35 | $state = self::shiftRows($state, $Nb); |
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| 36 | $state = self::mixColumns($state, $Nb); |
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| 37 | $state = self::addRoundKey($state, $w, $round, $Nb); |
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| 38 | } |
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| 39 | ||
| 40 | $state = self::subBytes($state, $Nb); |
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| 41 | $state = self::shiftRows($state, $Nb); |
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| 42 | $state = self::addRoundKey($state, $w, $Nr, $Nb); |
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| 43 | ||
| 44 | $output = array(4 * $Nb); // convert state to 1-d array before returning [é3.4] |
|
| 45 | for ($i = 0; $i < 4 * $Nb; $i++) { |
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| 46 | $output[$i] = $state[$i % 4][floor($i / 4)]; |
|
| 47 | } |
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| 48 | ||
| 49 | return $output; |
|
| 50 | } |
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| 51 | ||
| 52 | /** |
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| 53 | * @param integer $rnd |
|
| 54 | * @param integer $Nb |
|
| 55 | */ |
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| 56 | private static function addRoundKey($state, $w, $rnd, $Nb) |
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| 57 | { |
|
| 58 | // xor Round Key into state S [é5.1.4] |
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| 59 | for ($r = 0; $r < 4; $r++) { |
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| 60 | for ($c = 0; $c < $Nb; $c++) { |
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| 61 | $state[$r][$c] ^= $w[$rnd * 4 + $c][$r]; |
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| 62 | } |
|
| 63 | } |
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| 64 | ||
| 65 | return $state; |
|
| 66 | } |
|
| 67 | ||
| 68 | /** |
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| 69 | * @param integer $Nb |
|
| 70 | */ |
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| 71 | private static function subBytes($s, $Nb) |
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| 72 | { |
|
| 73 | // apply SBox to state S [é5.1.1] |
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| 74 | for ($r = 0; $r < 4; $r++) { |
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| 75 | for ($c = 0; $c < $Nb; $c++) { |
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| 76 | $s[$r][$c] = self::$sBox[$s[$r][$c]]; |
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| 77 | } |
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| 78 | } |
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| 79 | ||
| 80 | return $s; |
|
| 81 | } |
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| 82 | ||
| 83 | /** |
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| 84 | * @param integer $Nb |
|
| 85 | */ |
|
| 86 | private static function shiftRows($s, $Nb) |
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| 87 | { |
|
| 88 | // shift row r of state S left by r bytes [é5.1.2] |
|
| 89 | $t = array(4); |
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| 90 | for ($r = 1; $r < 4; $r++) { |
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| 91 | for ($c = 0; $c < 4; $c++) { |
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| 92 | $t[$c] = $s[$r][($c + $r) % $Nb]; // shift into temp copy |
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| 93 | } |
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| 94 | for ($c = 0; $c < 4; $c++) { |
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| 95 | $s[$r][$c] = $t[$c]; // and copy back |
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| 96 | } |
|
| 97 | } // note that this will work for Nb=4,5,6, but not 7,8 (always 4 for AES): |
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| 98 | return $s; // see fp.gladman.plus.com/cryptography_technology/rijndael/aes.spec.311.pdf |
|
| 99 | } |
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| 100 | ||
| 101 | /** |
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| 102 | * @param integer $Nb |
|
| 103 | */ |
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| 104 | private static function mixColumns($s, $Nb) |
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| 105 | { |
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| 106 | // combine bytes of each col of state S [é5.1.3] |
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| 107 | for ($c = 0; $c < 4; $c++) { |
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| 108 | $a = array(4); // 'a' is a copy of the current column from 's' |
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| 109 | $b = array(4); // 'b' is aé{02} in GF(2^8) |
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| 110 | for ($i = 0; $i < 4; $i++) { |
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| 111 | $a[$i] = $s[$i][$c]; |
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| 112 | $b[$i] = $s[$i][$c] & 0x80 ? $s[$i][$c] << 1 ^ 0x011b : $s[$i][$c] << 1; |
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| 113 | } |
|
| 114 | // a[n] ^ b[n] is aé{03} in GF(2^8) |
|
| 115 | $s[0][$c] = $b[0] ^ $a[1] ^ $b[1] ^ $a[2] ^ $a[3]; // 2*a0 + 3*a1 + a2 + a3 |
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| 116 | $s[1][$c] = $a[0] ^ $b[1] ^ $a[2] ^ $b[2] ^ $a[3]; // a0 * 2*a1 + 3*a2 + a3 |
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| 117 | $s[2][$c] = $a[0] ^ $a[1] ^ $b[2] ^ $a[3] ^ $b[3]; // a0 + a1 + 2*a2 + 3*a3 |
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| 118 | $s[3][$c] = $a[0] ^ $b[0] ^ $a[1] ^ $a[2] ^ $b[3]; // 3*a0 + a1 + a2 + 2*a3 |
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| 119 | } |
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| 120 | ||
| 121 | return $s; |
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| 122 | } |
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| 123 | ||
| 124 | /** |
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| 125 | * Key expansion for Rijndael cipher(): performs key expansion on cipher key |
|
| 126 | * to generate a key schedule |
|
| 127 | * |
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| 128 | * @param key cipher key byte-array (16 bytes) |
|
| 129 | * @return key schedule as 2D byte-array (Nr+1 x Nb bytes) |
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| 130 | */ |
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| 131 | public static function keyExpansion($key) |
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| 132 | { |
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| 133 | // generate Key Schedule from Cipher Key [é5.2] |
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| 134 | $Nb = 4; // block size (in words): no of columns in state (fixed at 4 for AES) |
|
| 135 | $Nk = count($key) / 4; // key length (in words): 4/6/8 for 128/192/256-bit keys |
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| 136 | $Nr = $Nk + 6; // no of rounds: 10/12/14 for 128/192/256-bit keys |
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| 137 | ||
| 138 | $w = array(); |
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| 139 | $temp = array(); |
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| 140 | ||
| 141 | for ($i = 0; $i < $Nk; $i++) { |
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| 142 | $r = array($key[4 * $i], $key[4 * $i + 1], $key[4 * $i + 2], $key[4 * $i + 3]); |
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| 143 | $w[$i] = $r; |
|
| 144 | } |
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| 145 | ||
| 146 | for ($i = $Nk; $i < ($Nb * ($Nr + 1)); $i++) { |
|
| 147 | $w[$i] = array(); |
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| 148 | for ($t = 0; $t < 4; $t++) { |
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| 149 | $temp[$t] = $w[$i - 1][$t]; |
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| 150 | } |
|
| 151 | if ($i % $Nk == 0) { |
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| 152 | $temp = self::subWord(self::rotWord($temp)); |
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| 153 | for ($t = 0; $t < 4; $t++) { |
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| 154 | $temp[$t] ^= self::$rCon[$i / $Nk][$t]; |
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| 155 | } |
|
| 156 | } elseif ($Nk > 6 && $i % $Nk == 4) { |
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| 157 | $temp = self::subWord($temp); |
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| 158 | } |
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| 159 | for ($t = 0; $t < 4; $t++) { |
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| 160 | $w[$i][$t] = $w[$i - $Nk][$t] ^ $temp[$t]; |
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| 161 | } |
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| 162 | } |
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| 163 | ||
| 164 | return $w; |
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| 165 | } |
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| 166 | ||
| 167 | private static function subWord($w) |
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| 168 | { |
|
| 169 | // apply SBox to 4-byte word w |
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| 170 | for ($i = 0; $i < 4; $i++) { |
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| 171 | $w[$i] = self::$sBox[$w[$i]]; |
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| 172 | } |
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| 173 | ||
| 174 | return $w; |
|
| 175 | } |
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| 176 | ||
| 177 | private static function rotWord($w) |
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| 178 | { |
|
| 179 | // rotate 4-byte word w left by one byte |
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| 180 | $tmp = $w[0]; |
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| 181 | for ($i = 0; $i < 3; $i++) { |
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| 182 | $w[$i] = $w[$i + 1]; |
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| 183 | } |
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| 184 | $w[3] = $tmp; |
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| 185 | ||
| 186 | return $w; |
|
| 187 | } |
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| 188 | ||
| 189 | // sBox is pre-computed multiplicative inverse in GF(2^8) used in subBytes and keyExpansion [é5.1.1] |
|
| 190 | private static $sBox = array( |
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| 191 | 0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5, 0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76, |
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| 192 | 0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0, 0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0, |
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| 193 | 0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc, 0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15, |
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| 194 | 0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a, 0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75, |
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| 195 | 0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0, 0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84, |
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| 196 | 0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b, 0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf, |
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| 197 | 0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85, 0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8, |
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| 198 | 0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5, 0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2, |
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| 199 | 0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17, 0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73, |
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| 200 | 0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88, 0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb, |
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| 201 | 0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c, 0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79, |
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| 202 | 0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9, 0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08, |
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| 203 | 0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6, 0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a, |
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| 204 | 0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e, 0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e, |
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| 205 | 0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94, 0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf, |
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| 206 | 0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68, 0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16 |
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| 207 | ); |
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| 208 | ||
| 209 | // rCon is Round Constant used for the Key Expansion [1st col is 2^(r-1) in GF(2^8)] [é5.2] |
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| 210 | private static $rCon = array( |
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| 211 | array(0x00, 0x00, 0x00, 0x00), |
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| 212 | array(0x01, 0x00, 0x00, 0x00), |
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| 213 | array(0x02, 0x00, 0x00, 0x00), |
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| 214 | array(0x04, 0x00, 0x00, 0x00), |
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| @@ 7-168 (lines=162) @@ | ||
| 4 | /* commercial or non-commercial use under CC-BY licence. No warranty of any form is offered. */ |
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| 5 | /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ |
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| 6 | ||
| 7 | class Aes |
|
| 8 | { |
|
| 9 | /** |
|
| 10 | * AES Cipher function: encrypt 'input' with Rijndael algorithm |
|
| 11 | * |
|
| 12 | * @param input message as byte-array (16 bytes) |
|
| 13 | * @param w key schedule as 2D byte-array (Nr+1 x Nb bytes) - |
|
| 14 | * generated from the cipher key by keyExpansion() |
|
| 15 | * @return ciphertext as byte-array (16 bytes) |
|
| 16 | */ |
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| 17 | public static function cipher($input, $w) { // main cipher function [é5.1] |
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| 18 | $Nb = 4; // block size (in words): no of columns in state (fixed at 4 for AES) |
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| 19 | $Nr = count($w) / $Nb - 1; // no of rounds: 10/12/14 for 128/192/256-bit keys |
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| 20 | ||
| 21 | $state = array(); // initialise 4xNb byte-array 'state' with input [é3.4] |
|
| 22 | for ($i = 0; $i < 4 * $Nb; $i++) { |
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| 23 | $state[$i % 4][floor($i / 4)] = $input[$i]; |
|
| 24 | } |
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| 25 | ||
| 26 | $state = self::addRoundKey($state, $w, 0, $Nb); |
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| 27 | ||
| 28 | for ($round = 1; $round < $Nr; $round++) { // apply Nr rounds |
|
| 29 | $state = self::subBytes($state, $Nb); |
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| 30 | $state = self::shiftRows($state, $Nb); |
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| 31 | $state = self::mixColumns($state, $Nb); |
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| 32 | $state = self::addRoundKey($state, $w, $round, $Nb); |
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| 33 | } |
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| 34 | ||
| 35 | $state = self::subBytes($state, $Nb); |
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| 36 | $state = self::shiftRows($state, $Nb); |
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| 37 | $state = self::addRoundKey($state, $w, $Nr, $Nb); |
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| 38 | ||
| 39 | $output = array(4 * $Nb); // convert state to 1-d array before returning [é3.4] |
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| 40 | for ($i = 0; $i < 4 * $Nb; $i++) { |
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| 41 | $output[$i] = $state[$i % 4][floor($i / 4)]; |
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| 42 | } |
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| 43 | ||
| 44 | return $output; |
|
| 45 | } |
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| 46 | ||
| 47 | /** |
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| 48 | * @param integer $rnd |
|
| 49 | * @param integer $Nb |
|
| 50 | */ |
|
| 51 | private static function addRoundKey($state, $w, $rnd, $Nb) { // xor Round Key into state S [é5.1.4] |
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| 52 | for ($r = 0; $r < 4; $r++) { |
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| 53 | for ($c = 0; $c < $Nb; $c++) { |
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| 54 | $state[$r][$c] ^= $w[$rnd * 4 + $c][$r]; |
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| 55 | } |
|
| 56 | } |
|
| 57 | ||
| 58 | return $state; |
|
| 59 | } |
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| 60 | ||
| 61 | /** |
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| 62 | * @param integer $Nb |
|
| 63 | */ |
|
| 64 | private static function subBytes($s, $Nb) { // apply SBox to state S [é5.1.1] |
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| 65 | for ($r = 0; $r < 4; $r++) { |
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| 66 | for ($c = 0; $c < $Nb; $c++) { |
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| 67 | $s[$r][$c] = self::$sBox[$s[$r][$c]]; |
|
| 68 | } |
|
| 69 | } |
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| 70 | ||
| 71 | return $s; |
|
| 72 | } |
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| 73 | ||
| 74 | /** |
|
| 75 | * @param integer $Nb |
|
| 76 | */ |
|
| 77 | private static function shiftRows($s, $Nb) { // shift row r of state S left by r bytes [é5.1.2] |
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| 78 | $t = array(4); |
|
| 79 | for ($r = 1; $r < 4; $r++) { |
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| 80 | for ($c = 0; $c < 4; $c++) { |
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| 81 | $t[$c] = $s[$r][($c + $r) % $Nb]; |
|
| 82 | } |
|
| 83 | // shift into temp copy |
|
| 84 | for ($c = 0; $c < 4; $c++) { |
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| 85 | $s[$r][$c] = $t[$c]; |
|
| 86 | } |
|
| 87 | // and copy back |
|
| 88 | } // note that this will work for Nb=4,5,6, but not 7,8 (always 4 for AES): |
|
| 89 | return $s; // see fp.gladman.plus.com/cryptography_technology/rijndael/aes.spec.311.pdf |
|
| 90 | } |
|
| 91 | ||
| 92 | /** |
|
| 93 | * @param integer $Nb |
|
| 94 | */ |
|
| 95 | private static function mixColumns($s, $Nb) { // combine bytes of each col of state S [é5.1.3] |
|
| 96 | for ($c = 0; $c < 4; $c++) { |
|
| 97 | $a = array(4); // 'a' is a copy of the current column from 's' |
|
| 98 | $b = array(4); // 'b' is aé{02} in GF(2^8) |
|
| 99 | for ($i = 0; $i < 4; $i++) { |
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| 100 | $a[$i] = $s[$i][$c]; |
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| 101 | $b[$i] = $s[$i][$c] & 0x80 ? $s[$i][$c] << 1 ^ 0x011b : $s[$i][$c] << 1; |
|
| 102 | } |
|
| 103 | // a[n] ^ b[n] is aé{03} in GF(2^8) |
|
| 104 | $s[0][$c] = $b[0] ^ $a[1] ^ $b[1] ^ $a[2] ^ $a[3]; // 2*a0 + 3*a1 + a2 + a3 |
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| 105 | $s[1][$c] = $a[0] ^ $b[1] ^ $a[2] ^ $b[2] ^ $a[3]; // a0 * 2*a1 + 3*a2 + a3 |
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| 106 | $s[2][$c] = $a[0] ^ $a[1] ^ $b[2] ^ $a[3] ^ $b[3]; // a0 + a1 + 2*a2 + 3*a3 |
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| 107 | $s[3][$c] = $a[0] ^ $b[0] ^ $a[1] ^ $a[2] ^ $b[3]; // 3*a0 + a1 + a2 + 2*a3 |
|
| 108 | } |
|
| 109 | ||
| 110 | return $s; |
|
| 111 | } |
|
| 112 | ||
| 113 | /** |
|
| 114 | * Key expansion for Rijndael cipher(): performs key expansion on cipher key |
|
| 115 | * to generate a key schedule |
|
| 116 | * |
|
| 117 | * @param key cipher key byte-array (16 bytes) |
|
| 118 | * @return key schedule as 2D byte-array (Nr+1 x Nb bytes) |
|
| 119 | */ |
|
| 120 | public static function keyExpansion($key) { // generate Key Schedule from Cipher Key [é5.2] |
|
| 121 | $Nb = 4; // block size (in words): no of columns in state (fixed at 4 for AES) |
|
| 122 | $Nk = count($key) / 4; // key length (in words): 4/6/8 for 128/192/256-bit keys |
|
| 123 | $Nr = $Nk + 6; // no of rounds: 10/12/14 for 128/192/256-bit keys |
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| 124 | ||
| 125 | $w = array(); |
|
| 126 | $temp = array(); |
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| 127 | ||
| 128 | for ($i = 0; $i < $Nk; $i++) { |
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| 129 | $r = array($key[4 * $i], $key[4 * $i + 1], $key[4 * $i + 2], $key[4 * $i + 3]); |
|
| 130 | $w[$i] = $r; |
|
| 131 | } |
|
| 132 | ||
| 133 | for ($i = $Nk; $i < ($Nb * ($Nr + 1)); $i++) { |
|
| 134 | $w[$i] = array(); |
|
| 135 | for ($t = 0; $t < 4; $t++) { |
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| 136 | $temp[$t] = $w[$i - 1][$t]; |
|
| 137 | } |
|
| 138 | if ($i % $Nk == 0) { |
|
| 139 | $temp = self::subWord(self::rotWord($temp)); |
|
| 140 | for ($t = 0; $t < 4; $t++) { |
|
| 141 | $temp[$t] ^= self::$rCon[$i / $Nk][$t]; |
|
| 142 | } |
|
| 143 | } elseif ($Nk > 6 && $i % $Nk == 4) { |
|
| 144 | $temp = self::subWord($temp); |
|
| 145 | } |
|
| 146 | for ($t = 0; $t < 4; $t++) { |
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| 147 | $w[$i][$t] = $w[$i - $Nk][$t] ^ $temp[$t]; |
|
| 148 | } |
|
| 149 | } |
|
| 150 | ||
| 151 | return $w; |
|
| 152 | } |
|
| 153 | ||
| 154 | private static function subWord($w) { // apply SBox to 4-byte word w |
|
| 155 | for ($i = 0; $i < 4; $i++) { |
|
| 156 | $w[$i] = self::$sBox[$w[$i]]; |
|
| 157 | } |
|
| 158 | ||
| 159 | return $w; |
|
| 160 | } |
|
| 161 | ||
| 162 | private static function rotWord($w) { // rotate 4-byte word w left by one byte |
|
| 163 | $tmp = $w[0]; |
|
| 164 | for ($i = 0; $i < 3; $i++) { |
|
| 165 | $w[$i] = $w[$i + 1]; |
|
| 166 | } |
|
| 167 | $w[3] = $tmp; |
|
| 168 | ||
| 169 | return $w; |
|
| 170 | } |
|
| 171 | ||
| @@ 10-211 (lines=202) @@ | ||
| 7 | /* form is offered. */ |
|
| 8 | /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ |
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| 9 | ||
| 10 | class Aes |
|
| 11 | { |
|
| 12 | /** |
|
| 13 | * AES Cipher function: encrypt 'input' with Rijndael algorithm |
|
| 14 | * |
|
| 15 | * @param input message as byte-array (16 bytes) |
|
| 16 | * @param w key schedule as 2D byte-array (Nr+1 x Nb bytes) - |
|
| 17 | * generated from the cipher key by keyExpansion() |
|
| 18 | * @return ciphertext as byte-array (16 bytes) |
|
| 19 | */ |
|
| 20 | public static function cipher($input, $w) |
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| 21 | { |
|
| 22 | // main cipher function [é5.1] |
|
| 23 | $Nb = 4; // block size (in words): no of columns in state (fixed at 4 for AES) |
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| 24 | $Nr = count($w) / $Nb - 1; // no of rounds: 10/12/14 for 128/192/256-bit keys |
|
| 25 | ||
| 26 | $state = array(); // initialise 4xNb byte-array 'state' with input [é3.4] |
|
| 27 | for ($i = 0; $i < 4 * $Nb; $i++) { |
|
| 28 | $state[$i % 4][floor($i / 4)] = $input[$i]; |
|
| 29 | } |
|
| 30 | ||
| 31 | $state = self::addRoundKey($state, $w, 0, $Nb); |
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| 32 | ||
| 33 | for ($round = 1; $round < $Nr; $round++) { // apply Nr rounds |
|
| 34 | $state = self::subBytes($state, $Nb); |
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| 35 | $state = self::shiftRows($state, $Nb); |
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| 36 | $state = self::mixColumns($state, $Nb); |
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| 37 | $state = self::addRoundKey($state, $w, $round, $Nb); |
|
| 38 | } |
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| 39 | ||
| 40 | $state = self::subBytes($state, $Nb); |
|
| 41 | $state = self::shiftRows($state, $Nb); |
|
| 42 | $state = self::addRoundKey($state, $w, $Nr, $Nb); |
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| 43 | ||
| 44 | $output = array(4 * $Nb); // convert state to 1-d array before returning [é3.4] |
|
| 45 | for ($i = 0; $i < 4 * $Nb; $i++) { |
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| 46 | $output[$i] = $state[$i % 4][floor($i / 4)]; |
|
| 47 | } |
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| 48 | ||
| 49 | return $output; |
|
| 50 | } |
|
| 51 | ||
| 52 | /** |
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| 53 | * @param integer $rnd |
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| 54 | * @param integer $Nb |
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| 55 | */ |
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| 56 | private static function addRoundKey($state, $w, $rnd, $Nb) |
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| 57 | { |
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| 58 | // xor Round Key into state S [é5.1.4] |
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| 59 | for ($r = 0; $r < 4; $r++) { |
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| 60 | for ($c = 0; $c < $Nb; $c++) { |
|
| 61 | $state[$r][$c] ^= $w[$rnd * 4 + $c][$r]; |
|
| 62 | } |
|
| 63 | } |
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| 64 | ||
| 65 | return $state; |
|
| 66 | } |
|
| 67 | ||
| 68 | /** |
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| 69 | * @param integer $Nb |
|
| 70 | */ |
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| 71 | private static function subBytes($s, $Nb) |
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| 72 | { |
|
| 73 | // apply SBox to state S [é5.1.1] |
|
| 74 | for ($r = 0; $r < 4; $r++) { |
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| 75 | for ($c = 0; $c < $Nb; $c++) { |
|
| 76 | $s[$r][$c] = self::$sBox[$s[$r][$c]]; |
|
| 77 | } |
|
| 78 | } |
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| 79 | ||
| 80 | return $s; |
|
| 81 | } |
|
| 82 | ||
| 83 | /** |
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| 84 | * @param integer $Nb |
|
| 85 | */ |
|
| 86 | private static function shiftRows($s, $Nb) |
|
| 87 | { |
|
| 88 | // shift row r of state S left by r bytes [é5.1.2] |
|
| 89 | $t = array(4); |
|
| 90 | for ($r = 1; $r < 4; $r++) { |
|
| 91 | for ($c = 0; $c < 4; $c++) { |
|
| 92 | $t[$c] = $s[$r][($c + $r) % $Nb]; // shift into temp copy |
|
| 93 | } |
|
| 94 | for ($c = 0; $c < 4; $c++) { |
|
| 95 | $s[$r][$c] = $t[$c]; // and copy back |
|
| 96 | } |
|
| 97 | } // note that this will work for Nb=4,5,6, but not 7,8 (always 4 for AES): |
|
| 98 | return $s; // see fp.gladman.plus.com/cryptography_technology/rijndael/aes.spec.311.pdf |
|
| 99 | } |
|
| 100 | ||
| 101 | /** |
|
| 102 | * @param integer $Nb |
|
| 103 | */ |
|
| 104 | private static function mixColumns($s, $Nb) |
|
| 105 | { |
|
| 106 | // combine bytes of each col of state S [é5.1.3] |
|
| 107 | for ($c = 0; $c < 4; $c++) { |
|
| 108 | $a = array(4); // 'a' is a copy of the current column from 's' |
|
| 109 | $b = array(4); // 'b' is aé{02} in GF(2^8) |
|
| 110 | for ($i = 0; $i < 4; $i++) { |
|
| 111 | $a[$i] = $s[$i][$c]; |
|
| 112 | $b[$i] = $s[$i][$c] & 0x80 ? $s[$i][$c] << 1 ^ 0x011b : $s[$i][$c] << 1; |
|
| 113 | } |
|
| 114 | // a[n] ^ b[n] is aé{03} in GF(2^8) |
|
| 115 | $s[0][$c] = $b[0] ^ $a[1] ^ $b[1] ^ $a[2] ^ $a[3]; // 2*a0 + 3*a1 + a2 + a3 |
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| 116 | $s[1][$c] = $a[0] ^ $b[1] ^ $a[2] ^ $b[2] ^ $a[3]; // a0 * 2*a1 + 3*a2 + a3 |
|
| 117 | $s[2][$c] = $a[0] ^ $a[1] ^ $b[2] ^ $a[3] ^ $b[3]; // a0 + a1 + 2*a2 + 3*a3 |
|
| 118 | $s[3][$c] = $a[0] ^ $b[0] ^ $a[1] ^ $a[2] ^ $b[3]; // 3*a0 + a1 + a2 + 2*a3 |
|
| 119 | } |
|
| 120 | ||
| 121 | return $s; |
|
| 122 | } |
|
| 123 | ||
| 124 | /** |
|
| 125 | * Key expansion for Rijndael cipher(): performs key expansion on cipher key |
|
| 126 | * to generate a key schedule |
|
| 127 | * |
|
| 128 | * @param key cipher key byte-array (16 bytes) |
|
| 129 | * @return key schedule as 2D byte-array (Nr+1 x Nb bytes) |
|
| 130 | */ |
|
| 131 | public static function keyExpansion($key) |
|
| 132 | { |
|
| 133 | // generate Key Schedule from Cipher Key [é5.2] |
|
| 134 | $Nb = 4; // block size (in words): no of columns in state (fixed at 4 for AES) |
|
| 135 | $Nk = count($key) / 4; // key length (in words): 4/6/8 for 128/192/256-bit keys |
|
| 136 | $Nr = $Nk + 6; // no of rounds: 10/12/14 for 128/192/256-bit keys |
|
| 137 | ||
| 138 | $w = array(); |
|
| 139 | $temp = array(); |
|
| 140 | ||
| 141 | for ($i = 0; $i < $Nk; $i++) { |
|
| 142 | $r = array($key[4 * $i], $key[4 * $i + 1], $key[4 * $i + 2], $key[4 * $i + 3]); |
|
| 143 | $w[$i] = $r; |
|
| 144 | } |
|
| 145 | ||
| 146 | for ($i = $Nk; $i < ($Nb * ($Nr + 1)); $i++) { |
|
| 147 | $w[$i] = array(); |
|
| 148 | for ($t = 0; $t < 4; $t++) { |
|
| 149 | $temp[$t] = $w[$i - 1][$t]; |
|
| 150 | } |
|
| 151 | if ($i % $Nk == 0) { |
|
| 152 | $temp = self::subWord(self::rotWord($temp)); |
|
| 153 | for ($t = 0; $t < 4; $t++) { |
|
| 154 | $temp[$t] ^= self::$rCon[$i / $Nk][$t]; |
|
| 155 | } |
|
| 156 | } elseif ($Nk > 6 && $i % $Nk == 4) { |
|
| 157 | $temp = self::subWord($temp); |
|
| 158 | } |
|
| 159 | for ($t = 0; $t < 4; $t++) { |
|
| 160 | $w[$i][$t] = $w[$i - $Nk][$t] ^ $temp[$t]; |
|
| 161 | } |
|
| 162 | } |
|
| 163 | ||
| 164 | return $w; |
|
| 165 | } |
|
| 166 | ||
| 167 | private static function subWord($w) |
|
| 168 | { |
|
| 169 | // apply SBox to 4-byte word w |
|
| 170 | for ($i = 0; $i < 4; $i++) { |
|
| 171 | $w[$i] = self::$sBox[$w[$i]]; |
|
| 172 | } |
|
| 173 | ||
| 174 | return $w; |
|
| 175 | } |
|
| 176 | ||
| 177 | private static function rotWord($w) |
|
| 178 | { |
|
| 179 | // rotate 4-byte word w left by one byte |
|
| 180 | $tmp = $w[0]; |
|
| 181 | for ($i = 0; $i < 3; $i++) { |
|
| 182 | $w[$i] = $w[$i + 1]; |
|
| 183 | } |
|
| 184 | $w[3] = $tmp; |
|
| 185 | ||
| 186 | return $w; |
|
| 187 | } |
|
| 188 | ||
| 189 | // sBox is pre-computed multiplicative inverse in GF(2^8) used in subBytes and keyExpansion [é5.1.1] |
|
| 190 | private static $sBox = array( |
|
| 191 | 0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5, 0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76, |
|
| 192 | 0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0, 0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0, |
|
| 193 | 0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc, 0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15, |
|
| 194 | 0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a, 0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75, |
|
| 195 | 0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0, 0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84, |
|
| 196 | 0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b, 0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf, |
|
| 197 | 0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85, 0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8, |
|
| 198 | 0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5, 0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2, |
|
| 199 | 0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17, 0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73, |
|
| 200 | 0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88, 0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb, |
|
| 201 | 0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c, 0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79, |
|
| 202 | 0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9, 0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08, |
|
| 203 | 0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6, 0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a, |
|
| 204 | 0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e, 0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e, |
|
| 205 | 0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94, 0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf, |
|
| 206 | 0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68, 0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16 |
|
| 207 | ); |
|
| 208 | ||
| 209 | // rCon is Round Constant used for the Key Expansion [1st col is 2^(r-1) in GF(2^8)] [é5.2] |
|
| 210 | private static $rCon = array( |
|
| 211 | array(0x00, 0x00, 0x00, 0x00), |
|
| 212 | array(0x01, 0x00, 0x00, 0x00), |
|
| 213 | array(0x02, 0x00, 0x00, 0x00), |
|
| 214 | array(0x04, 0x00, 0x00, 0x00), |
|
