src/SHA.cpp

   1 //
   2 // This file is part of the aMule Project.
   3 //
   4 // Copyright (c) 2003-2008 Angel Vidal (Kry) ( kry@amule.org )
   5 // Copyright (c) 2003-2008 aMule Team ( admin@amule.org / http://www.amule.org )
   6 //
   7 // Any parts of this program derived from the xMule, lMule or eMule project,
   8 // or contributed by third-party developers are copyrighted by their
   9 // respective authors.
  10 //
  11 // This program is free software; you can redistribute it and/or modify
  12 // it under the terms of the GNU General Public License as published by
  13 // the Free Software Foundation; either version 2 of the License, or
  14 // (at your option) any later version.
  15 //
  16 // This program is distributed in the hope that it will be useful,
  17 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 // GNU General Public License for more details.
  20 //
  21 // You should have received a copy of the GNU General Public License
  22 // along with this program; if not, write to the Free Software
  23 // Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301, USA
  24 //
  25 // Kry - Modified version of the original SHA.cpp to work on linux and
  26 // use wxWidgets. Original license follows.
  27 //
  28
  29 /*
  30  ---------------------------------------------------------------------------
  31  Copyright (c) 2002, Dr Brian Gladman <brg@gladman.me.uk>, Worcester, UK.
  32  All rights reserved.
  33
  34  LICENSE TERMS
  35
  36  The free distribution and use of this software in both source and binary
  37  form is allowed (with or without changes) provided that:
  38
  39    1. distributions of this source code include the above copyright
  40       notice, this list of conditions and the following disclaimer;
  41
  42    2. distributions in binary form include the above copyright
  43       notice, this list of conditions and the following disclaimer
  44       in the documentation and/or other associated materials;
  45
  46    3. the copyright holder's name is not used to endorse products
  47       built using this software without specific written permission.
  48
  49  ALTERNATIVELY, provided that this notice is retained in full, this product
  50  may be distributed under the terms of the GNU General Public License (GPL),
  51  in which case the provisions of the GPL apply INSTEAD OF those given above.
  52
  53  DISCLAIMER
  54
  55  This software is provided 'as is' with no explicit or implied warranties
  56  in respect of its properties, including, but not limited to, correctness
  57  and/or fitness for purpose.
  58  ---------------------------------------------------------------------------
  59  Issue Date: 30/11/2002
  60
  61  This is a byte oriented version of SHA1 that operates on arrays of bytes
  62  stored in memory. It runs at 22 cycles per byte on a Pentium P4 processor
  63 */
  64
  65 #include "SHA.h"
  66
  67
  68 CSHA::CSHA()
  69 {
  70         Reset();
  71 }
  72
  73 /*
  74     To obtain the highest speed on processors with 32-bit words, this code
  75     needs to determine the order in which bytes are packed into such words.
  76     The following block of code is an attempt to capture the most obvious
  77     ways in which various environemnts specify their endian definitions.
  78     It may well fail, in which case the definitions will need to be set by
  79     editing at the points marked **** EDIT HERE IF NECESSARY **** below.
  80 */
  81 #define SHA_LITTLE_ENDIAN   1234 /* byte 0 is least significant (i386) */
  82 #define SHA_BIG_ENDIAN      4321 /* byte 0 is most significant (mc68k) */
  83
  84 #define rotl32(x,n) (((x) << n) | ((x) >> (32 - n)))
  85
  86 #if (wxBYTE_ORDER == wxBIG_ENDIAN)
  87 #define swap_b32(x) (x)
  88 #elif defined(bswap_32)
  89 #define swap_b32(x) bswap_32(x)
  90 #else
  91 #define swap_b32(x) ((rotl32((x), 8) & 0x00ff00ff) | (rotl32((x), 24) & 0xff00ff00))
  92 #endif
  93
  94 #define SHA1_MASK   (SHA1_BLOCK_SIZE - 1)
  95
  96 /* reverse byte order in 32-bit words   */
  97
  98 #define ch(x,y,z)       (((x) & (y)) ^ (~(x) & (z)))
  99 #define parity(x,y,z)   ((x) ^ (y) ^ (z))
 100 #define maj(x,y,z)      (((x) & (y)) ^ ((x) & (z)) ^ ((y) & (z)))
 101
 102 /* A normal version as set out in the FIPS. This version uses   */
 103 /* partial loop unrolling and is optimised for the Pentium 4    */
 104
 105 #define rnd(f,k) t = a; a = rotl32(a,5) + f(b,c,d) + e + k + w[i]; e = d; d = c; c = rotl32(b, 30); b = t
 106
 107 void CSHA::Compile()
 108 {
 109         uint32    w[80], i, a, b, c, d, e, t;
 110
 111     /* note that words are compiled from the buffer into 32-bit */
 112     /* words in big-endian order so an order reversal is needed */
 113     /* here on little endian machines                           */
 114     for(i = 0; i < SHA1_BLOCK_SIZE / 4; ++i)
 115         w[i] = swap_b32(m_nBuffer[i]);
 116
 117     for(i = SHA1_BLOCK_SIZE / 4; i < 80; ++i)
 118         w[i] = rotl32(w[i - 3] ^ w[i - 8] ^ w[i - 14] ^ w[i - 16], 1);
 119
 120     a = m_nHash[0];
 121     b = m_nHash[1];
 122     c = m_nHash[2];
 123     d = m_nHash[3];
 124     e = m_nHash[4];
 125
 126     for(i = 0; i < 20; ++i)
 127     {
 128         rnd(ch, 0x5a827999);
 129     }
 130
 131     for(i = 20; i < 40; ++i)
 132     {
 133         rnd(parity, 0x6ed9eba1);
 134     }
 135
 136     for(i = 40; i < 60; ++i)
 137     {
 138         rnd(maj, 0x8f1bbcdc);
 139     }
 140
 141     for(i = 60; i < 80; ++i)
 142     {
 143         rnd(parity, 0xca62c1d6);
 144     }
 145
 146     m_nHash[0] += a;
 147     m_nHash[1] += b;
 148     m_nHash[2] += c;
 149     m_nHash[3] += d;
 150     m_nHash[4] += e;
 151 }
 152
 153 void CSHA::Reset()
 154 {
 155     m_nCount[0] = m_nCount[1] = 0;
 156     m_nHash[0] = 0x67452301;
 157     m_nHash[1] = 0xefcdab89;
 158     m_nHash[2] = 0x98badcfe;
 159     m_nHash[3] = 0x10325476;
 160     m_nHash[4] = 0xc3d2e1f0;
 161 }
 162
 163 void CSHA::GetHash(CAICHHash& Hash)
 164 {
 165     /* extract the hash value as bytes in case the hash buffer is   */
 166     /* misaligned for 32-bit words*/
 167
 168         wxASSERT( Hash.GetHashSize() == 20 );
 169     for(int i = 0; i < SHA1_DIGEST_SIZE; ++i)
 170         Hash.GetRawHash()[i] = (unsigned char)(m_nHash[i >> 2] >> 8 * (~i & 3));
 171 }
 172
 173 /* SHA1 hash data in an array of bytes into hash buffer and call the        */
 174 /* hash_compile function as required.                                       */
 175
 176 void CSHA::Add(const void* pData, uint32 nLength)
 177 {
 178         const unsigned char* data = (const unsigned char*)pData;
 179
 180         uint32 pos = (uint32)(m_nCount[0] & SHA1_MASK),
 181              space = SHA1_BLOCK_SIZE - pos;
 182     const unsigned char *sp = data;
 183
 184     if((m_nCount[0] += nLength) < nLength)
 185         ++(m_nCount[1]);
 186
 187     while(nLength >= space)     /* tranfer whole blocks while possible  */
 188     {
 189         memcpy(((unsigned char*)m_nBuffer) + pos, sp, space);
 190         sp += space; nLength -= space; space = SHA1_BLOCK_SIZE; pos = 0;
 191         Compile();
 192     }
 193
 194     memcpy(((unsigned char*)m_nBuffer) + pos, sp, nLength);
 195 }
 196
 197 /* SHA1 final padding and digest calculation  */
 198
 199 #if (wxBYTE_ORDER == wxLITTLE_ENDIAN)
 200 static uint32  mask[4] =
 201         {   0x00000000, 0x000000ff, 0x0000ffff, 0x00ffffff };
 202 static uint32  bits[4] =
 203         {   0x00000080, 0x00008000, 0x00800000, 0x80000000 };
 204 #else
 205 static uint32  mask[4] =
 206         {   0x00000000, 0xff000000, 0xffff0000, 0xffffff00 };
 207 static uint32  bits[4] =
 208         {   0x80000000, 0x00800000, 0x00008000, 0x00000080 };
 209 #endif
 210
 211 void CSHA::Finish(CAICHHash& Hash)
 212 {
 213         uint32    i = (uint32)(m_nCount[0] & SHA1_MASK);
 214
 215     /* mask out the rest of any partial 32-bit word and then set    */
 216     /* the next byte to 0x80. On big-endian machines any bytes in   */
 217     /* the buffer will be at the top end of 32 bit words, on little */
 218     /* endian machines they will be at the bottom. Hence the AND    */
 219     /* and OR masks above are reversed for little endian systems    */
 220         /* Note that we can always add the first padding byte at this   */
 221         /* because the buffer always contains at least one empty slot   */
 222     m_nBuffer[i >> 2] = (m_nBuffer[i >> 2] & mask[i & 3]) | bits[i & 3];
 223
 224     /* we need 9 or more empty positions, one for the padding byte  */
 225     /* (above) and eight for the length count.  If there is not     */
 226     /* enough space pad and empty the buffer                        */
 227     if(i > SHA1_BLOCK_SIZE - 9)
 228     {
 229         if(i < 60) m_nBuffer[15] = 0;
 230         Compile();
 231         i = 0;
 232     }
 233     else    /* compute a word index for the empty buffer positions  */
 234         i = (i >> 2) + 1;
 235
 236     while(i < 14) /* and zero pad all but last two positions      */
 237         m_nBuffer[i++] = 0;
 238
 239     /* assemble the eight byte counter in in big-endian format          */
 240     m_nBuffer[14] = swap_b32((m_nCount[1] << 3) | (m_nCount[0] >> 29));
 241     m_nBuffer[15] = swap_b32(m_nCount[0] << 3);
 242
 243     Compile();
 244         GetHash(Hash);
 245 }
 246 // File_checked_for_headers