mcs/class/Mono.Security/Mono.Security.Cryptography/SHA224Managed.cs

   1 //
   2 // Mono.Security.Cryptography SHA224 class implementation
   3 //      based on SHA256Managed class implementation (mscorlib.dll)
   4 //
   5 // Authors:
   6 //      Matthew S. Ford (Matthew.S.Ford@Rose-Hulman.Edu)
   7 //      Sebastien Pouliot <sebastien@ximian.com>
   8 //
   9 // (C) 2001
  10 // Copyright (C) 2004-2005 Novell, Inc (http://www.novell.com)
  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.Security.Cryptography;
  33
  34 namespace Mono.Security.Cryptography {
  35
  36         public class SHA224Managed : SHA224 {
  37
  38                 private const int BLOCK_SIZE_BYTES =  64;
  39
  40                 private uint[] _H;
  41                 private ulong count;
  42                 private byte[] _ProcessingBuffer;   // Used to start data when passed less than a block worth.
  43                 private int _ProcessingBufferCount; // Counts how much data we have stored that still needs processed.
  44                 private uint[] buff;
  45
  46                 public SHA224Managed ()
  47                 {
  48                         _H = new uint [8];
  49                         _ProcessingBuffer = new byte [BLOCK_SIZE_BYTES];
  50                         buff = new uint[64];
  51                         Initialize ();
  52                 }
  53
  54                 private uint Ch (uint u, uint v, uint w)
  55                 {
  56                         return (u&v) ^ (~u&w);
  57                 }
  58
  59                 private uint Maj (uint u, uint v, uint w)
  60                 {
  61                         return (u&v) ^ (u&w) ^ (v&w);
  62                 }
  63
  64                 private uint Ro0 (uint x)
  65                 {
  66                         return ((x >> 7) | (x << 25))
  67                                 ^ ((x >> 18) | (x << 14))
  68                                 ^ (x >> 3);
  69                 }
  70
  71                 private uint Ro1 (uint x)
  72                 {
  73                         return ((x >> 17) | (x << 15))
  74                                 ^ ((x >> 19) | (x << 13))
  75                                 ^ (x >> 10);
  76                 }
  77
  78                 private uint Sig0 (uint x)
  79                 {
  80                         return ((x >> 2) | (x << 30))
  81                                 ^ ((x >> 13) | (x << 19))
  82                                 ^ ((x >> 22) | (x << 10));
  83                 }
  84
  85                 private uint Sig1 (uint x)
  86                 {
  87                         return ((x >> 6) | (x << 26))
  88                                 ^ ((x >> 11) | (x << 21))
  89                                 ^ ((x >> 25) | (x << 7));
  90                 }
  91
  92                 protected override void HashCore (byte[] rgb, int start, int size)
  93                 {
  94                         int i;
  95                         State = 1;
  96
  97                         if (_ProcessingBufferCount != 0) {
  98                                 if (size < (BLOCK_SIZE_BYTES - _ProcessingBufferCount)) {
  99                                         System.Buffer.BlockCopy (rgb, start, _ProcessingBuffer, _ProcessingBufferCount, size);
 100                                         _ProcessingBufferCount += size;
 101                                         return;
 102                                 }
 103                                 else {
 104                                         i = (BLOCK_SIZE_BYTES - _ProcessingBufferCount);
 105                                         System.Buffer.BlockCopy (rgb, start, _ProcessingBuffer, _ProcessingBufferCount, i);
 106                                         ProcessBlock (_ProcessingBuffer, 0);
 107                                         _ProcessingBufferCount = 0;
 108                                         start += i;
 109                                         size -= i;
 110                                 }
 111                         }
 112
 113                         for (i=0; i<size-size%BLOCK_SIZE_BYTES; i += BLOCK_SIZE_BYTES) {
 114                                 ProcessBlock (rgb, start+i);
 115                         }
 116
 117                         if (size%BLOCK_SIZE_BYTES != 0) {
 118                                 System.Buffer.BlockCopy (rgb, size-size%BLOCK_SIZE_BYTES+start, _ProcessingBuffer, 0, size%BLOCK_SIZE_BYTES);
 119                                 _ProcessingBufferCount = size%BLOCK_SIZE_BYTES;
 120                         }
 121                 }
 122
 123                 protected override byte[] HashFinal ()
 124                 {
 125                         byte[] hash = new byte[28];
 126                         int i, j;
 127
 128                         ProcessFinalBlock (_ProcessingBuffer, 0, _ProcessingBufferCount);
 129
 130                         for (i=0; i<7; i++) {
 131                                 for (j=0; j<4; j++) {
 132                                         hash[i*4+j] = (byte)(_H[i] >> (24-j*8));
 133                                 }
 134                         }
 135
 136                         State = 0;
 137                         return hash;
 138                 }
 139
 140                 public override void Initialize ()
 141                 {
 142                         count = 0;
 143                         _ProcessingBufferCount = 0;
 144
 145                         _H[0] = 0xC1059ED8;
 146                         _H[1] = 0x367CD507;
 147                         _H[2] = 0x3070DD17;
 148                         _H[3] = 0xF70E5939;
 149                         _H[4] = 0xFFC00B31;
 150                         _H[5] = 0x68581511;
 151                         _H[6] = 0x64F98FA7;
 152                         _H[7] = 0xBEFA4FA4;
 153                 }
 154
 155                 private void ProcessBlock (byte[] inputBuffer, int inputOffset)
 156                 {
 157                         uint a, b, c, d, e, f, g, h;
 158                         uint t1, t2;
 159                         int i;
 160                         uint[] K1 = SHAConstants.K1;
 161                         uint[] buff = this.buff;
 162
 163                         count += BLOCK_SIZE_BYTES;
 164
 165                         for (i=0; i<16; i++) {
 166                                 buff[i] = (uint)(((inputBuffer[inputOffset+4*i]) << 24)
 167                                         | ((inputBuffer[inputOffset+4*i+1]) << 16)
 168                                         | ((inputBuffer[inputOffset+4*i+2]) <<  8)
 169                                         | ((inputBuffer[inputOffset+4*i+3])));
 170                         }
 171
 172
 173                         for (i=16; i<64; i++) {
 174                                 t1 = buff[i - 15];
 175                                 t1 = (((t1 >> 7) | (t1 << 25)) ^ ((t1 >> 18) | (t1 << 14)) ^ (t1 >> 3));
 176
 177                                 t2 = buff[i - 2];
 178                                 t2 = (((t2 >> 17) | (t2 << 15)) ^ ((t2 >> 19) | (t2 << 13)) ^ (t2 >> 10));
 179                                 buff[i] = t2 + buff[i - 7] + t1 + buff[i - 16];
 180                         }
 181
 182                         a = _H[0];
 183                         b = _H[1];
 184                         c = _H[2];
 185                         d = _H[3];
 186                         e = _H[4];
 187                         f = _H[5];
 188                         g = _H[6];
 189                         h = _H[7];
 190
 191                         for (i=0; i<64; i++) {
 192                                 t1 = h + (((e >> 6) | (e << 26)) ^ ((e >> 11) | (e << 21)) ^ ((e >> 25) | (e << 7))) + ((e & f) ^ (~e & g)) + K1[i] + buff[i];
 193
 194                                 t2 = (((a >> 2) | (a << 30)) ^ ((a >> 13) | (a << 19)) ^ ((a >> 22) | (a << 10)));
 195                                 t2 = t2 + ((a & b) ^ (a & c) ^ (b & c));
 196                                 h = g;
 197                                 g = f;
 198                                 f = e;
 199                                 e = d + t1;
 200                                 d = c;
 201                                 c = b;
 202                                 b = a;
 203                                 a = t1 + t2;
 204                         }
 205
 206                         _H[0] += a;
 207                         _H[1] += b;
 208                         _H[2] += c;
 209                         _H[3] += d;
 210                         _H[4] += e;
 211                         _H[5] += f;
 212                         _H[6] += g;
 213                         _H[7] += h;
 214                 }
 215
 216                 private void ProcessFinalBlock (byte[] inputBuffer, int inputOffset, int inputCount)
 217                 {
 218                         ulong total = count + (ulong)inputCount;
 219                         int paddingSize = (56 - (int)(total % BLOCK_SIZE_BYTES));
 220
 221                         if (paddingSize < 1)
 222                                 paddingSize += BLOCK_SIZE_BYTES;
 223
 224                         byte[] fooBuffer = new byte[inputCount+paddingSize+8];
 225
 226                         for (int i=0; i<inputCount; i++) {
 227                                 fooBuffer[i] = inputBuffer[i+inputOffset];
 228                         }
 229
 230                         fooBuffer[inputCount] = 0x80;
 231                         for (int i=inputCount+1; i<inputCount+paddingSize; i++) {
 232                                 fooBuffer[i] = 0x00;
 233                         }
 234
 235                         // I deal in bytes. The algorithm deals in bits.
 236                         ulong size = total << 3;
 237                         AddLength (size, fooBuffer, inputCount+paddingSize);
 238                         ProcessBlock (fooBuffer, 0);
 239
 240                         if (inputCount+paddingSize+8 == 128) {
 241                                 ProcessBlock(fooBuffer, 64);
 242                         }
 243                 }
 244
 245                 internal void AddLength (ulong length, byte[] buffer, int position)
 246                 {
 247                         buffer [position++] = (byte)(length >> 56);
 248                         buffer [position++] = (byte)(length >> 48);
 249                         buffer [position++] = (byte)(length >> 40);
 250                         buffer [position++] = (byte)(length >> 32);
 251                         buffer [position++] = (byte)(length >> 24);
 252                         buffer [position++] = (byte)(length >> 16);
 253                         buffer [position++] = (byte)(length >>  8);
 254                         buffer [position]   = (byte)(length);
 255                 }
 256         }
 257 }
 258