mcs/class/corlib/System.Security.Cryptography/SHA512Managed.cs

   1 //
   2 // System.Security.Cryptography.SHA512Managed.cs
   3 //
   4 // Authors:
   5 //      Dan Lewis (dihlewis@yahoo.co.uk)
   6 //      Sebastien Pouliot (sebastien@ximian.com)
   7 //
   8 // (C) 2002
   9 // Implementation translated from Bouncy Castle JCE (http://www.bouncycastle.org/)
  10 // See bouncycastle.txt for license.
  11 // (C) 2004 Novell (http://www.novell.com)
  12 //
  13
  14 //
  15 // Copyright (C) 2004 Novell, Inc (http://www.novell.com)
  16 //
  17 // Permission is hereby granted, free of charge, to any person obtaining
  18 // a copy of this software and associated documentation files (the
  19 // "Software"), to deal in the Software without restriction, including
  20 // without limitation the rights to use, copy, modify, merge, publish,
  21 // distribute, sublicense, and/or sell copies of the Software, and to
  22 // permit persons to whom the Software is furnished to do so, subject to
  23 // the following conditions:
  24 //
  25 // The above copyright notice and this permission notice shall be
  26 // included in all copies or substantial portions of the Software.
  27 //
  28 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  29 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  30 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  31 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  32 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  33 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  34 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  35 //
  36
  37 using System;
  38
  39 namespace System.Security.Cryptography {
  40
  41 public class SHA512Managed : SHA512 {
  42
  43         private byte[] xBuf;
  44         private int xBufOff;
  45
  46         private ulong byteCount1;
  47         private ulong byteCount2;
  48
  49         private ulong H1, H2, H3, H4, H5, H6, H7, H8;
  50
  51         private ulong[] W;
  52         private int wOff;
  53
  54         public SHA512Managed ()
  55         {
  56                 xBuf = new byte [8];
  57                 W = new ulong [80];
  58                 Initialize (false); // limited initialization
  59         }
  60
  61         private void Initialize (bool reuse)
  62         {
  63                 // SHA-512 initial hash value
  64                 // The first 64 bits of the fractional parts of the square roots
  65                 // of the first eight prime numbers
  66                 H1 = 0x6a09e667f3bcc908L;
  67                 H2 = 0xbb67ae8584caa73bL;
  68                 H3 = 0x3c6ef372fe94f82bL;
  69                 H4 = 0xa54ff53a5f1d36f1L;
  70                 H5 = 0x510e527fade682d1L;
  71                 H6 = 0x9b05688c2b3e6c1fL;
  72                 H7 = 0x1f83d9abfb41bd6bL;
  73                 H8 = 0x5be0cd19137e2179L;
  74
  75                 if (reuse) {
  76                         byteCount1 = 0;
  77                         byteCount2 = 0;
  78
  79                         xBufOff = 0;
  80                         for (int i = 0; i < xBuf.Length; i++)
  81                                 xBuf [i] = 0;
  82
  83                         wOff = 0;
  84                         for (int i = 0; i != W.Length; i++)
  85                                 W [i] = 0;
  86                 }
  87         }
  88
  89         public override void Initialize ()
  90         {
  91                 Initialize (true); // reuse instance
  92         }
  93
  94         // protected
  95
  96         protected override void HashCore (byte[] rgb, int start, int count)
  97         {
  98                 // fill the current word
  99                 while ((xBufOff != 0) && (count > 0)) {
 100                         update (rgb [start]);
 101                         start++;
 102                         count--;
 103                 }
 104
 105                 // process whole words.
 106                 while (count > xBuf.Length) {
 107                         processWord (rgb, start);
 108                         start += xBuf.Length;
 109                         count -= xBuf.Length;
 110                         byteCount1 += (ulong) xBuf.Length;
 111                 }
 112
 113                 // load in the remainder.
 114                 while (count > 0) {
 115                         update (rgb [start]);
 116                         start++;
 117                         count--;
 118                 }
 119         }
 120
 121         protected override byte[] HashFinal ()
 122         {
 123                 adjustByteCounts ();
 124
 125                 ulong lowBitLength = byteCount1 << 3;
 126                 ulong hiBitLength = byteCount2;
 127
 128                 // add the pad bytes.
 129                 update (128);
 130                 while (xBufOff != 0)
 131                         update (0);
 132
 133                 processLength (lowBitLength, hiBitLength);
 134                 processBlock ();
 135
 136                 byte[] output = new byte [64];
 137                 unpackWord(H1, output, 0);
 138                 unpackWord(H2, output, 8);
 139                 unpackWord(H3, output, 16);
 140                 unpackWord(H4, output, 24);
 141                 unpackWord(H5, output, 32);
 142                 unpackWord(H6, output, 40);
 143                 unpackWord(H7, output, 48);
 144                 unpackWord(H8, output, 56);
 145
 146                 Initialize ();
 147                 return output;
 148         }
 149
 150         private void update (byte input)
 151         {
 152                 xBuf [xBufOff++] = input;
 153                 if (xBufOff == xBuf.Length) {
 154                         processWord(xBuf, 0);
 155                         xBufOff = 0;
 156                 }
 157                 byteCount1++;
 158         }
 159
 160         private void processWord (byte[] input, int inOff)
 161         {
 162                 W [wOff++] = ( (ulong) input [inOff] << 56)
 163                         | ( (ulong) input [inOff + 1] << 48)
 164                         | ( (ulong) input [inOff + 2] << 40)
 165                         | ( (ulong) input [inOff + 3] << 32)
 166                         | ( (ulong) input [inOff + 4] << 24)
 167                         | ( (ulong) input [inOff + 5] << 16)
 168                         | ( (ulong) input [inOff + 6] << 8)
 169                         | ( (ulong) input [inOff + 7]);
 170                 if (wOff == 16)
 171                         processBlock ();
 172         }
 173
 174         private void unpackWord (ulong word, byte[] output, int outOff)
 175         {
 176                 output[outOff]     = (byte) (word >> 56);
 177                 output[outOff + 1] = (byte) (word >> 48);
 178                 output[outOff + 2] = (byte) (word >> 40);
 179                 output[outOff + 3] = (byte) (word >> 32);
 180                 output[outOff + 4] = (byte) (word >> 24);
 181                 output[outOff + 5] = (byte) (word >> 16);
 182                 output[outOff + 6] = (byte) (word >> 8);
 183                 output[outOff + 7] = (byte) word;
 184         }
 185
 186         // adjust the byte counts so that byteCount2 represents the
 187         // upper long (less 3 bits) word of the byte count.
 188         private void adjustByteCounts ()
 189         {
 190                 if (byteCount1 > 0x1fffffffffffffffL) {
 191                         byteCount2 += (byteCount1 >> 61);
 192                         byteCount1 &= 0x1fffffffffffffffL;
 193                 }
 194         }
 195
 196         private void processLength (ulong lowW, ulong hiW)
 197         {
 198                 if (wOff > 14)
 199                         processBlock();
 200                 W[14] = hiW;
 201                 W[15] = lowW;
 202         }
 203
 204         private void processBlock ()
 205         {
 206                 adjustByteCounts ();
 207                 // expand 16 word block into 80 word blocks.
 208                 for (int t = 16; t <= 79; t++)
 209                         W[t] = Sigma1 (W [t - 2]) + W [t - 7] + Sigma0 (W [t - 15]) + W [t - 16];
 210
 211                 // set up working variables.
 212                 ulong a = H1;
 213                 ulong b = H2;
 214                 ulong c = H3;
 215                 ulong d = H4;
 216                 ulong e = H5;
 217                 ulong f = H6;
 218                 ulong g = H7;
 219                 ulong h = H8;
 220
 221                 for (int t = 0; t <= 79; t++) {
 222                         ulong T1 = h + Sum1 (e) + Ch (e, f, g) + SHAConstants.K2 [t] + W [t];
 223                         ulong T2 = Sum0 (a) + Maj (a, b, c);
 224                         h = g;
 225                         g = f;
 226                         f = e;
 227                         e = d + T1;
 228                         d = c;
 229                         c = b;
 230                         b = a;
 231                         a = T1 + T2;
 232                 }
 233
 234                 H1 += a;
 235                 H2 += b;
 236                 H3 += c;
 237                 H4 += d;
 238                 H5 += e;
 239                 H6 += f;
 240                 H7 += g;
 241                 H8 += h;
 242                 // reset the offset and clean out the word buffer.
 243                 wOff = 0;
 244                 for (int i = 0; i != W.Length; i++)
 245                         W[i] = 0;
 246         }
 247
 248         private ulong rotateRight (ulong x, int n)
 249         {
 250                 return (x >> n) | (x << (64 - n));
 251         }
 252
 253         /* SHA-512 and SHA-512 functions (as for SHA-256 but for longs) */
 254         private ulong Ch (ulong x, ulong y, ulong z)
 255         {
 256                 return ((x & y) ^ ((~x) & z));
 257         }
 258
 259         private ulong Maj (ulong x, ulong y, ulong z)
 260         {
 261                 return ((x & y) ^ (x & z) ^ (y & z));
 262         }
 263
 264         private ulong Sum0 (ulong x)
 265         {
 266                 return rotateRight (x, 28) ^ rotateRight (x, 34) ^ rotateRight (x, 39);
 267         }
 268
 269         private ulong Sum1 (ulong x)
 270         {
 271                 return rotateRight (x, 14) ^ rotateRight (x, 18) ^ rotateRight (x, 41);
 272         }
 273
 274         private ulong Sigma0 (ulong x)
 275         {
 276                 return rotateRight (x, 1) ^ rotateRight(x, 8) ^ (x >> 7);
 277         }
 278
 279         private ulong Sigma1 (ulong x)
 280         {
 281                 return rotateRight (x, 19) ^ rotateRight (x, 61) ^ (x >> 6);
 282         }
 283 }
 284
 285 }