mcs/class/Mono.Security/Mono.Security.Cryptography/MD4Managed.cs

   1 //
   2 // MD4Managed.cs - Message Digest 4 Managed Implementation
   3 //
   4 // Author:
   5 //      Sebastien Pouliot (sebastien@ximian.com)
   6 //
   7 // (C) 2003 Motus Technologies Inc. (http://www.motus.com)
   8 // (C) 2004 Novell (http://www.novell.com)
   9 //
  10
  11 //
  12 // Permission is hereby granted, free of charge, to any person obtaining
  13 // a copy of this software and associated documentation files (the
  14 // "Software"), to deal in the Software without restriction, including
  15 // without limitation the rights to use, copy, modify, merge, publish,
  16 // distribute, sublicense, and/or sell copies of the Software, and to
  17 // permit persons to whom the Software is furnished to do so, subject to
  18 // the following conditions:
  19 //
  20 // The above copyright notice and this permission notice shall be
  21 // included in all copies or substantial portions of the Software.
  22 //
  23 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  27 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  28 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  29 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  30 //
  31
  32 using System;
  33
  34 namespace Mono.Security.Cryptography {
  35
  36         // References:
  37         // a.     RFC1320: The MD4 Message-Digest Algorithm
  38         //        http://www.ietf.org/rfc/rfc1320.txt
  39
  40         public class MD4Managed : MD4 {
  41
  42                 private uint[] state;
  43                 private byte[] buffer;
  44                 private uint[] count;
  45                 private uint[] x;
  46
  47                 private const int S11 = 3;
  48                 private const int S12 = 7;
  49                 private const int S13 = 11;
  50                 private const int S14 = 19;
  51                 private const int S21 = 3;
  52                 private const int S22 = 5;
  53                 private const int S23 = 9;
  54                 private const int S24 = 13;
  55                 private const int S31 = 3;
  56                 private const int S32 = 9;
  57                 private const int S33 = 11;
  58                 private const int S34 = 15;
  59
  60                 private byte[] digest;
  61
  62                 //--- constructor -----------------------------------------------------------
  63
  64                 public MD4Managed () : base ()
  65                 {
  66                         // we allocate the context memory
  67                         state = new uint [4];
  68                         count = new uint [2];
  69                         buffer = new byte [64];
  70                         digest = new byte [16];
  71                         // the initialize our context
  72                         Initialize ();
  73                 }
  74
  75                 public override void Initialize ()
  76                 {
  77                         count [0] = 0;
  78                         count [1] = 0;
  79                         state [0] = 0x67452301;
  80                         state [1] = 0xefcdab89;
  81                         state [2] = 0x98badcfe;
  82                         state [3] = 0x10325476;
  83                         // temporary buffer in MD4Transform that we don't want to keep allocate on each iteration
  84                         x = new uint [16];
  85                         Array.Clear (buffer, 0, 64);
  86                 }
  87
  88                 protected override void HashCore (byte[] array, int ibStart, int cbSize)
  89                 {
  90                         /* Compute number of bytes mod 64 */
  91                         int index = (int) ((count [0] >> 3) & 0x3F);
  92                         /* Update number of bits */
  93                         count [0] += (uint) (cbSize << 3);
  94                         if (count [0] < (cbSize << 3))
  95                                 count [1]++;
  96                         count [1] += (uint) (cbSize >> 29);
  97
  98                         int partLen = 64 - index;
  99                         int i = 0;
 100                         /* Transform as many times as possible. */
 101                         if (cbSize >= partLen) {
 102                                 //MD4_memcpy((POINTER)&context->buffer[index], (POINTER)input, partLen);
 103                                 Buffer.BlockCopy (array, ibStart, buffer, index, partLen);
 104                                 MD4Transform (state, buffer, 0);
 105
 106                                 for (i = partLen; i + 63 < cbSize; i += 64) {
 107                                         // MD4Transform (context->state, &input[i]);
 108                                         MD4Transform (state, array, i);
 109                                 }
 110
 111                                 index = 0;
 112                         }
 113
 114                         /* Buffer remaining input */
 115                         //MD4_memcpy ((POINTER)&context->buffer[index], (POINTER)&input[i], inputLen-i);
 116                         Buffer.BlockCopy (array, ibStart + i, buffer, index, (cbSize-i));
 117                 }
 118
 119                 protected override byte[] HashFinal ()
 120                 {
 121                         /* Save number of bits */
 122                         byte[] bits = new byte [8];
 123                         Encode (bits, count);
 124
 125                         /* Pad out to 56 mod 64. */
 126                         uint index = ((count [0] >> 3) & 0x3f);
 127                         int padLen = (int) ((index < 56) ? (56 - index) : (120 - index));
 128                         HashCore (Padding (padLen), 0, padLen);
 129
 130                         /* Append length (before padding) */
 131                         HashCore (bits, 0, 8);
 132
 133                         /* Store state in digest */
 134                         Encode (digest, state);
 135
 136                         // Zeroize sensitive information.
 137                         Initialize ();
 138
 139                         return digest;
 140                 }
 141
 142                 //--- private methods ---------------------------------------------------
 143
 144                 private byte[] Padding (int nLength)
 145                 {
 146                         if (nLength > 0) {
 147                                 byte[] padding = new byte [nLength];
 148                                 padding [0] = 0x80;
 149                                 return padding;
 150                         }
 151                         return null;
 152                 }
 153
 154                 /* F, G and H are basic MD4 functions. */
 155                 private uint F (uint x, uint y, uint z)
 156                 {
 157                         return (uint) (((x) & (y)) | ((~x) & (z)));
 158                 }
 159
 160                 private uint G (uint x, uint y, uint z)
 161                 {
 162                         return (uint) (((x) & (y)) | ((x) & (z)) | ((y) & (z)));
 163                 }
 164
 165                 private uint H (uint x, uint y, uint z)
 166                 {
 167                         return (uint) ((x) ^ (y) ^ (z));
 168                 }
 169
 170                 /* ROTATE_LEFT rotates x left n bits. */
 171                 private uint ROL (uint x, byte n)
 172                 {
 173                         return (uint) (((x) << (n)) | ((x) >> (32-(n))));
 174                 }
 175
 176                 /* FF, GG and HH are transformations for rounds 1, 2 and 3 */
 177                 /* Rotation is separate from addition to prevent recomputation */
 178                 private void FF (ref uint a, uint b, uint c, uint d, uint x, byte s)
 179                 {
 180                         a += F (b, c, d) + x;
 181                         a = ROL (a, s);
 182                 }
 183
 184                 private void GG (ref uint a, uint b, uint c, uint d, uint x, byte s)
 185                 {
 186                         a += G (b, c, d) + x + 0x5a827999;
 187                         a = ROL (a, s);
 188                 }
 189
 190                 private void HH (ref uint a, uint b, uint c, uint d, uint x, byte s)
 191                 {
 192                         a += H (b, c, d) + x + 0x6ed9eba1;
 193                         a = ROL (a, s);
 194                 }
 195
 196                 private void Encode (byte[] output, uint[] input)
 197                 {
 198                         for (int i = 0, j = 0; j < output.Length; i++, j += 4) {
 199                                 output [j]   = (byte)(input [i] & 0xff);
 200                                 output [j+1] = (byte)((input [i] >> 8) & 0xff);
 201                                 output [j+2] = (byte)((input [i] >> 16) & 0xff);
 202                                 output [j+3] = (byte)(input [i] >> 24);
 203                         }
 204                 }
 205
 206                 private void Decode (uint[] output, byte[] input, int index)
 207                 {
 208                         for (int i = 0, j = index; i < output.Length; i++, j += 4) {
 209                                 output [i] = (uint) ((input [j]) | (input [j+1] << 8) | (input [j+2] << 16) | (input [j+3] << 24));
 210                         }
 211                 }
 212
 213                 private void MD4Transform (uint[] state, byte[] block, int index)
 214                 {
 215                         uint a = state [0];
 216                         uint b = state [1];
 217                         uint c = state [2];
 218                         uint d = state [3];
 219
 220                         Decode (x, block, index);
 221
 222                         /* Round 1 */
 223                         FF (ref a, b, c, d, x[ 0], S11); /* 1 */
 224                         FF (ref d, a, b, c, x[ 1], S12); /* 2 */
 225                         FF (ref c, d, a, b, x[ 2], S13); /* 3 */
 226                         FF (ref b, c, d, a, x[ 3], S14); /* 4 */
 227                         FF (ref a, b, c, d, x[ 4], S11); /* 5 */
 228                         FF (ref d, a, b, c, x[ 5], S12); /* 6 */
 229                         FF (ref c, d, a, b, x[ 6], S13); /* 7 */
 230                         FF (ref b, c, d, a, x[ 7], S14); /* 8 */
 231                         FF (ref a, b, c, d, x[ 8], S11); /* 9 */
 232                         FF (ref d, a, b, c, x[ 9], S12); /* 10 */
 233                         FF (ref c, d, a, b, x[10], S13); /* 11 */
 234                         FF (ref b, c, d, a, x[11], S14); /* 12 */
 235                         FF (ref a, b, c, d, x[12], S11); /* 13 */
 236                         FF (ref d, a, b, c, x[13], S12); /* 14 */
 237                         FF (ref c, d, a, b, x[14], S13); /* 15 */
 238                         FF (ref b, c, d, a, x[15], S14); /* 16 */
 239
 240                         /* Round 2 */
 241                         GG (ref a, b, c, d, x[ 0], S21); /* 17 */
 242                         GG (ref d, a, b, c, x[ 4], S22); /* 18 */
 243                         GG (ref c, d, a, b, x[ 8], S23); /* 19 */
 244                         GG (ref b, c, d, a, x[12], S24); /* 20 */
 245                         GG (ref a, b, c, d, x[ 1], S21); /* 21 */
 246                         GG (ref d, a, b, c, x[ 5], S22); /* 22 */
 247                         GG (ref c, d, a, b, x[ 9], S23); /* 23 */
 248                         GG (ref b, c, d, a, x[13], S24); /* 24 */
 249                         GG (ref a, b, c, d, x[ 2], S21); /* 25 */
 250                         GG (ref d, a, b, c, x[ 6], S22); /* 26 */
 251                         GG (ref c, d, a, b, x[10], S23); /* 27 */
 252                         GG (ref b, c, d, a, x[14], S24); /* 28 */
 253                         GG (ref a, b, c, d, x[ 3], S21); /* 29 */
 254                         GG (ref d, a, b, c, x[ 7], S22); /* 30 */
 255                         GG (ref c, d, a, b, x[11], S23); /* 31 */
 256                         GG (ref b, c, d, a, x[15], S24); /* 32 */
 257
 258                         HH (ref a, b, c, d, x[ 0], S31); /* 33 */
 259                         HH (ref d, a, b, c, x[ 8], S32); /* 34 */
 260                         HH (ref c, d, a, b, x[ 4], S33); /* 35 */
 261                         HH (ref b, c, d, a, x[12], S34); /* 36 */
 262                         HH (ref a, b, c, d, x[ 2], S31); /* 37 */
 263                         HH (ref d, a, b, c, x[10], S32); /* 38 */
 264                         HH (ref c, d, a, b, x[ 6], S33); /* 39 */
 265                         HH (ref b, c, d, a, x[14], S34); /* 40 */
 266                         HH (ref a, b, c, d, x[ 1], S31); /* 41 */
 267                         HH (ref d, a, b, c, x[ 9], S32); /* 42 */
 268                         HH (ref c, d, a, b, x[ 5], S33); /* 43 */
 269                         HH (ref b, c, d, a, x[13], S34); /* 44 */
 270                         HH (ref a, b, c, d, x[ 3], S31); /* 45 */
 271                         HH (ref d, a, b, c, x[11], S32); /* 46 */
 272                         HH (ref c, d, a, b, x[ 7], S33); /* 47 */
 273                         HH (ref b, c, d, a, x[15], S34); /* 48 */
 274
 275                         state [0] += a;
 276                         state [1] += b;
 277                         state [2] += c;
 278                         state [3] += d;
 279
 280                         /* Zeroize sensitive information. */
 281                         Array.Clear (x, 0, 16);
 282                 }
 283         }
 284 }