aes_dec.c

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/*
+--------------------------------------------------------------------------+
| CHStone : a suite of benchmark programs for C-based High-Level Synthesis |
| ======================================================================== |
|                                                                          |
| * Collected and Modified : Y. Hara, H. Tomiyama, S. Honda,               |
|                            H. Takada and K. Ishii                        |
|                            Nagoya University, Japan                      |
|                                                                          |
| * Remark :                                                               |
|    1. This source code is modified to unify the formats of the benchmark |
|       programs in CHStone.                                               |
|    2. Test vectors are added for CHStone.                                |
|    3. If "main_result" is 0 at the end of the program, the program is    |
|       correctly executed.                                                |
|    4. Please follow the copyright of each benchmark program.             |
+--------------------------------------------------------------------------+
*/
/* aes_dec.c */
/*
 * Copyright (C) 2005
 * Akira Iwata & Masayuki Sato
 * Akira Iwata Laboratory,
 * Nagoya Institute of Technology in Japan.
 *
 * All rights reserved.
 *
 * This software is written by Masayuki Sato.
 * And if you want to contact us, send an email to Kimitake Wakayama
 * (wakayama@elcom.nitech.ac.jp)
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 * 
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 *
 * 3. All advertising materials mentioning features or use of this software must
 *    display the following acknowledgment:
 *    "This product includes software developed by Akira Iwata Laboratory,
 *    Nagoya Institute of Technology in Japan (http://mars.elcom.nitech.ac.jp/)."
 *
 * 4. Redistributions of any form whatsoever must retain the following
 *    acknowledgment:
 *    "This product includes software developed by Akira Iwata Laboratory,
 *     Nagoya Institute of Technology in Japan (http://mars.elcom.nitech.ac.jp/)."
 *
 *   THIS SOFTWARE IS PROVIDED "AS IS" WITHOUT EXPRESS OR IMPLIED WARRANTY.
 *   AKIRA IWATA LABORATORY DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
 *   SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS,
 *   IN NO EVENT SHALL AKIRA IWATA LABORATORY BE LIABLE FOR ANY SPECIAL,
 *   INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
 *   FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
 *   NEGLIGENCE OR OTHER TORTUOUS ACTION, ARISING OUT OF OR IN CONNECTION
 *   WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 */
int
decrypt (int statemt[32], int key[32], int type)
{
  int i;
/*
+--------------------------------------------------------------------------+
| * Test Vector (added for CHStone)                                        |
|     out_enc_statemt : expected output data for "decrypt"                 |
+--------------------------------------------------------------------------+
*/
  const int out_dec_statemt[16] =
    { 0x32, 0x43, 0xf6, 0xa8, 0x88, 0x5a, 0x30, 0x8d, 0x31, 0x31, 0x98, 0xa2,
    0xe0, 0x37, 0x7, 0x34
  };
  KeySchedule (type, key);

  switch (type)
    {
    case 128128:
      i_round = 10;
      nb = 4;
      break;
    case 128192:
    case 192192:
      i_round = 12;
      nb = 6;
      break;
    case 192128:
      i_round = 12;
      nb = 4;
      break;
    case 128256:
    case 192256:
      i_round = 14;
      nb = 8;
      break;
    case 256128:
      i_round = 14;
      nb = 4;
      break;
    case 256192:
      i_round = 14;
      nb = 6;
      break;
    case 256256:
      i_round = 14;
      nb = 8;
      break;
    }

  AddRoundKey (statemt, type, i_round);

  InversShiftRow_ByteSub (statemt, nb);

  for (i = i_round - 1; i >= 1; --i)
    {
      AddRoundKey_InversMixColumn (statemt, nb, i);
      InversShiftRow_ByteSub (statemt, nb);
    }

  AddRoundKey (statemt, type, 0);

  printf ("\ndecrypto message\t");
  for (i = 0; i < ((type % 1000) / 8); ++i)
    {
      if (statemt[i] < 16)
        printf ("0");
      printf ("%x", statemt[i]);
    }

  for (i = 0; i < 16; i++)
    main_result += (statemt[i] != out_dec_statemt[i]);

 return 0;
}