utils/zenutils/source/shared/crypt.cpp

   1 /* zenutils - Utilities for working with creative firmwares.
   2  * Copyright 2007 (c) Rasmus Ry <rasmus.ry{at}gmail.com>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  17  */
  18
  19 #include "crypt.h"
  20 #include <stdexcept>
  21 #include <beecrypt/hmacsha1.h>
  22 #include <beecrypt/blockmode.h>
  23 #include <beecrypt/blowfish.h>
  24
  25
  26 bool zen::hmac_sha1_calc(const byte* key, size_t keylen, const byte* data,
  27                          size_t datalen, byte* sig, size_t* siglen)
  28 {
  29     hmacsha1Param param;
  30     if (hmacsha1Setup(&param, key, keylen * 8))
  31         return false;
  32     if (hmacsha1Update(&param, data, datalen))
  33         return false;
  34     if (hmacsha1Digest(&param, sig))
  35         return false;
  36     return true;
  37 }
  38
  39 bool zen::bf_cbc_encrypt(const byte* key, size_t keylen, byte* data,
  40                          size_t datalen, const byte* iv)
  41 {
  42     if (datalen % blowfish.blocksize)
  43         throw std::invalid_argument(
  44             "The length must be aligned on a 8 byte boundary.");
  45
  46         blowfishParam param;
  47     if (blowfishSetup(&param, key, keylen * 8, ENCRYPT))
  48         return false;
  49     if (blowfishSetIV(&param, iv))
  50         return false;
  51
  52     byte* plain = new byte[datalen];
  53     memcpy(plain, data, datalen);
  54
  55     unsigned int nblocks = datalen / blowfish.blocksize;
  56     if (blockEncryptCBC(&blowfish, &param, (uint32_t*)data, (uint32_t*)plain,
  57                         nblocks))
  58     {
  59         delete [] plain;
  60         return false;
  61     }
  62
  63     return true;
  64 }
  65
  66 bool zen::bf_cbc_decrypt(const byte* key, size_t keylen, byte* data,
  67                          size_t datalen, const byte* iv)
  68 {
  69     if (datalen % blowfish.blocksize)
  70         throw std::invalid_argument(
  71             "The length must be aligned on a 8 byte boundary.");
  72
  73         blowfishParam param;
  74     if (blowfishSetup(&param, key, keylen * 8, ENCRYPT))
  75         return false;
  76     if (blowfishSetIV(&param, iv))
  77         return false;
  78
  79     byte* cipher = new byte[datalen];
  80     memcpy(cipher, data, datalen);
  81
  82     unsigned int nblocks = datalen / blowfish.blocksize;
  83     if (blockDecryptCBC(&blowfish, &param, (uint32_t*)data, (uint32_t*)cipher,
  84                         nblocks))
  85     {
  86         delete [] cipher;
  87         return false;
  88     }
  89
  90     return true;
  91 }