securemail/php-gpg/libs/GPG/AES.php

   1 <?php\r
   2 /** @package    php-gpg::GPG */\r
   3 \r
   4 /** require supporting files */\r
   5 require_once("Cipher.php");\r
   6 \r
   7 /**\r
   8  * @package    php-gpg::GPG\r
   9  */\r
  10 class GPG_AES\r
  11 {\r
  12         static function encrypt($block, $ctx)\r
  13         {\r
  14                 $RCON = GPG_Cipher::$RCON;\r
  15                 $S = GPG_Cipher::$S;\r
  16                 \r
  17                 $T1 = GPG_Cipher::$T1;\r
  18                 $T2 = GPG_Cipher::$T2;\r
  19                 $T3 = GPG_Cipher::$T3;\r
  20                 $T4 = GPG_Cipher::$T4;\r
  21                 \r
  22                 $r = 0;\r
  23                 $t0 = 0;\r
  24                 $t1 = 0;\r
  25                 $t2 = 0;\r
  26                 $t3 = 0;\r
  27                 \r
  28                 $b = GPG_Utility::pack_octets($block);\r
  29                 $rounds = $ctx->rounds;\r
  30                 $b0 = $b[0];\r
  31                 $b1 = $b[1];\r
  32                 $b2 = $b[2];\r
  33                 $b3 = $b[3];\r
  34                 \r
  35                 for($r = 0; $r < $rounds - 1; $r++) {\r
  36                         $t0 = $b0 ^ $ctx->rk[$r][0];\r
  37                         $t1 = $b1 ^ $ctx->rk[$r][1];\r
  38                         $t2 = $b2 ^ $ctx->rk[$r][2];\r
  39                         $t3 = $b3 ^ $ctx->rk[$r][3];\r
  40                         \r
  41                         $b0 = $T1[$t0 & 255] ^ $T2[($t1 >> 8) & 255] ^ $T3[($t2 >> 16) & 255] ^ $T4[GPG_Utility::zshift($t3, 24)];\r
  42                         $b1 = $T1[$t1 & 255] ^ $T2[($t2 >> 8) & 255] ^ $T3[($t3 >> 16) & 255] ^ $T4[GPG_Utility::zshift($t0, 24)];\r
  43                         $b2 = $T1[$t2 & 255] ^ $T2[($t3 >> 8) & 255] ^ $T3[($t0 >> 16) & 255] ^ $T4[GPG_Utility::zshift($t1, 24)];\r
  44                         $b3 = $T1[$t3 & 255] ^ $T2[($t0 >> 8) & 255] ^ $T3[($t1 >> 16) & 255] ^ $T4[GPG_Utility::zshift($t2, 24)];\r
  45                 }\r
  46                 \r
  47                 $r = $rounds - 1;\r
  48                 \r
  49                 $t0 = $b0 ^ $ctx->rk[$r][0];\r
  50                 $t1 = $b1 ^ $ctx->rk[$r][1];\r
  51                 $t2 = $b2 ^ $ctx->rk[$r][2];\r
  52                 $t3 = $b3 ^ $ctx->rk[$r][3];\r
  53                 \r
  54                 $b[0] = GPG_Cipher::F1($t0, $t1, $t2, $t3) ^ $ctx->rk[$rounds][0];\r
  55                 $b[1] = GPG_Cipher::F1($t1, $t2, $t3, $t0) ^ $ctx->rk[$rounds][1];\r
  56                 $b[2] = GPG_Cipher::F1($t2, $t3, $t0, $t1) ^ $ctx->rk[$rounds][2];\r
  57                 $b[3] = GPG_Cipher::F1($t3, $t0, $t1, $t2) ^ $ctx->rk[$rounds][3];\r
  58                 \r
  59                 return GPG_Utility::unpack_octets($b);\r
  60         }\r
  61 }\r
  62 \r
  63 ?>