git.distorted.org.uk Git - u/mdw/catacomb/blob - sha256.c

   1 /* -*-c-*-
   2  *
   3  * $Id: sha256.c,v 1.3 2004/04/08 01:36:15 mdw Exp $
   4  *
   5  * Implementation of the SHA-256 hash function
   6  *
   7  * (c) 2000 Straylight/Edgeware
   8  */
   9
  10 /*----- Licensing notice --------------------------------------------------*
  11  *
  12  * This file is part of Catacomb.
  13  *
  14  * Catacomb is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU Library General Public License as
  16  * published by the Free Software Foundation; either version 2 of the
  17  * License, or (at your option) any later version.
  18  *
  19  * Catacomb is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU Library General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU Library General Public
  25  * License along with Catacomb; if not, write to the Free
  26  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
  27  * MA 02111-1307, USA.
  28  */
  29
  30 /*----- Header files ------------------------------------------------------*/
  31
  32 #include <mLib/bits.h>
  33
  34 #include "ghash.h"
  35 #include "ghash-def.h"
  36 #include "hash.h"
  37 #include "sha256.h"
  38
  39 /*----- Main code ---------------------------------------------------------*/
  40
  41 /* --- @sha256_compress@, @sha224_compress@ --- *
  42  *
  43  * Arguments:   @sha256_ctx *ctx@ = pointer to context block
  44  *              @const void *sbuf@ = pointer to buffer of appropriate size
  45  *
  46  * Returns:     ---
  47  *
  48  * Use:         SHA-256 compression function.
  49  */
  50
  51 void sha256_compress(sha256_ctx *ctx, const void *sbuf)
  52 {
  53   uint32 a, b, c, d, e, f, g, h;
  54   uint32 buf[64];
  55
  56   /* --- Fetch the chaining variables --- */
  57
  58   a = ctx->a;
  59   b = ctx->b;
  60   c = ctx->c;
  61   d = ctx->d;
  62   e = ctx->e;
  63   f = ctx->f;
  64   g = ctx->g;
  65   h = ctx->h;
  66
  67   /* --- Definitions for round functions --- */
  68
  69 #define CH(x, y, z) (((x) & (y)) | (~(x) & (z)))
  70 #define MAJ(x, y, z) (((x) & (y)) | ((x) & (z)) | ((y) & (z)))
  71
  72 #define S0(x) (ROR32((x),  2) ^ ROR32((x), 13) ^ ROR32((x), 22))
  73 #define S1(x) (ROR32((x),  6) ^ ROR32((x), 11) ^ ROR32((x), 25))
  74 #define s0(x) (ROR32((x),  7) ^ ROR32((x), 18) ^ LSR32((x),  3))
  75 #define s1(x) (ROR32((x), 17) ^ ROR32((x), 19) ^ LSR32((x), 10))
  76
  77 #define T(a, b, c, d, e, f, g, h, i, k) do {                            \
  78   uint32 t1 = h + S1(e) + CH(e, f, g) + k + buf[i];                     \
  79   uint32 t2 = S0(a) + MAJ(a, b, c);                                     \
  80   d += t1; h = t1 + t2;                                                 \
  81 } while (0)
  82
  83   /* --- Fetch and expand the buffer contents --- */
  84
  85   {
  86     int i;
  87     const octet *p;
  88
  89     for (i = 0, p = sbuf; i < 16; i++, p += 4)
  90       buf[i] = LOAD32(p);
  91     for (i = 16; i < 64; i++)
  92       buf[i] = s1(buf[i - 2]) + buf[i - 7] + s0(buf[i - 15]) + buf[i - 16];
  93   }
  94
  95   /* --- The main compression function --- */
  96
  97   T(a, b, c, d, e, f, g, h,  0, 0x428a2f98);
  98   T(h, a, b, c, d, e, f, g,  1, 0x71374491);
  99   T(g, h, a, b, c, d, e, f,  2, 0xb5c0fbcf);
 100   T(f, g, h, a, b, c, d, e,  3, 0xe9b5dba5);
 101   T(e, f, g, h, a, b, c, d,  4, 0x3956c25b);
 102   T(d, e, f, g, h, a, b, c,  5, 0x59f111f1);
 103   T(c, d, e, f, g, h, a, b,  6, 0x923f82a4);
 104   T(b, c, d, e, f, g, h, a,  7, 0xab1c5ed5);
 105   T(a, b, c, d, e, f, g, h,  8, 0xd807aa98);
 106   T(h, a, b, c, d, e, f, g,  9, 0x12835b01);
 107   T(g, h, a, b, c, d, e, f, 10, 0x243185be);
 108   T(f, g, h, a, b, c, d, e, 11, 0x550c7dc3);
 109   T(e, f, g, h, a, b, c, d, 12, 0x72be5d74);
 110   T(d, e, f, g, h, a, b, c, 13, 0x80deb1fe);
 111   T(c, d, e, f, g, h, a, b, 14, 0x9bdc06a7);
 112   T(b, c, d, e, f, g, h, a, 15, 0xc19bf174);
 113   T(a, b, c, d, e, f, g, h, 16, 0xe49b69c1);
 114   T(h, a, b, c, d, e, f, g, 17, 0xefbe4786);
 115   T(g, h, a, b, c, d, e, f, 18, 0x0fc19dc6);
 116   T(f, g, h, a, b, c, d, e, 19, 0x240ca1cc);
 117   T(e, f, g, h, a, b, c, d, 20, 0x2de92c6f);
 118   T(d, e, f, g, h, a, b, c, 21, 0x4a7484aa);
 119   T(c, d, e, f, g, h, a, b, 22, 0x5cb0a9dc);
 120   T(b, c, d, e, f, g, h, a, 23, 0x76f988da);
 121   T(a, b, c, d, e, f, g, h, 24, 0x983e5152);
 122   T(h, a, b, c, d, e, f, g, 25, 0xa831c66d);
 123   T(g, h, a, b, c, d, e, f, 26, 0xb00327c8);
 124   T(f, g, h, a, b, c, d, e, 27, 0xbf597fc7);
 125   T(e, f, g, h, a, b, c, d, 28, 0xc6e00bf3);
 126   T(d, e, f, g, h, a, b, c, 29, 0xd5a79147);
 127   T(c, d, e, f, g, h, a, b, 30, 0x06ca6351);
 128   T(b, c, d, e, f, g, h, a, 31, 0x14292967);
 129   T(a, b, c, d, e, f, g, h, 32, 0x27b70a85);
 130   T(h, a, b, c, d, e, f, g, 33, 0x2e1b2138);
 131   T(g, h, a, b, c, d, e, f, 34, 0x4d2c6dfc);
 132   T(f, g, h, a, b, c, d, e, 35, 0x53380d13);
 133   T(e, f, g, h, a, b, c, d, 36, 0x650a7354);
 134   T(d, e, f, g, h, a, b, c, 37, 0x766a0abb);
 135   T(c, d, e, f, g, h, a, b, 38, 0x81c2c92e);
 136   T(b, c, d, e, f, g, h, a, 39, 0x92722c85);
 137   T(a, b, c, d, e, f, g, h, 40, 0xa2bfe8a1);
 138   T(h, a, b, c, d, e, f, g, 41, 0xa81a664b);
 139   T(g, h, a, b, c, d, e, f, 42, 0xc24b8b70);
 140   T(f, g, h, a, b, c, d, e, 43, 0xc76c51a3);
 141   T(e, f, g, h, a, b, c, d, 44, 0xd192e819);
 142   T(d, e, f, g, h, a, b, c, 45, 0xd6990624);
 143   T(c, d, e, f, g, h, a, b, 46, 0xf40e3585);
 144   T(b, c, d, e, f, g, h, a, 47, 0x106aa070);
 145   T(a, b, c, d, e, f, g, h, 48, 0x19a4c116);
 146   T(h, a, b, c, d, e, f, g, 49, 0x1e376c08);
 147   T(g, h, a, b, c, d, e, f, 50, 0x2748774c);
 148   T(f, g, h, a, b, c, d, e, 51, 0x34b0bcb5);
 149   T(e, f, g, h, a, b, c, d, 52, 0x391c0cb3);
 150   T(d, e, f, g, h, a, b, c, 53, 0x4ed8aa4a);
 151   T(c, d, e, f, g, h, a, b, 54, 0x5b9cca4f);
 152   T(b, c, d, e, f, g, h, a, 55, 0x682e6ff3);
 153   T(a, b, c, d, e, f, g, h, 56, 0x748f82ee);
 154   T(h, a, b, c, d, e, f, g, 57, 0x78a5636f);
 155   T(g, h, a, b, c, d, e, f, 58, 0x84c87814);
 156   T(f, g, h, a, b, c, d, e, 59, 0x8cc70208);
 157   T(e, f, g, h, a, b, c, d, 60, 0x90befffa);
 158   T(d, e, f, g, h, a, b, c, 61, 0xa4506ceb);
 159   T(c, d, e, f, g, h, a, b, 62, 0xbef9a3f7);
 160   T(b, c, d, e, f, g, h, a, 63, 0xc67178f2);
 161
 162   /* --- Update the chaining variables --- */
 163
 164   ctx->a += a;
 165   ctx->b += b;
 166   ctx->c += c;
 167   ctx->d += d;
 168   ctx->e += e;
 169   ctx->f += f;
 170   ctx->g += g;
 171   ctx->h += h;
 172 }
 173
 174 /* --- @sha256_init@, @sha224_init@ --- *
 175  *
 176  * Arguments:   @sha256_ctx *ctx@ = pointer to context block to initialize
 177  *
 178  * Returns:     ---
 179  *
 180  * Use:         Initializes a context block ready for hashing.
 181  */
 182
 183 void sha256_init(sha256_ctx *ctx)
 184 {
 185   ctx->a = 0x6a09e667;
 186   ctx->b = 0xbb67ae85;
 187   ctx->c = 0x3c6ef372;
 188   ctx->d = 0xa54ff53a;
 189   ctx->e = 0x510e527f;
 190   ctx->f = 0x9b05688c;
 191   ctx->g = 0x1f83d9ab;
 192   ctx->h = 0x5be0cd19;
 193   ctx->off = 0;
 194   ctx->nl = ctx->nh = 0;
 195 }
 196
 197 void sha224_init(sha256_ctx *ctx)
 198 {
 199   ctx->a = 0xc1059ed8;
 200   ctx->b = 0x367cd507;
 201   ctx->c = 0x3070dd17;
 202   ctx->d = 0xf70e5939;
 203   ctx->e = 0xffc00b31;
 204   ctx->f = 0x68581511;
 205   ctx->g = 0x64f98fa7;
 206   ctx->h = 0xbefa4fa4;
 207   ctx->off = 0;
 208   ctx->nl = ctx->nh = 0;
 209 }
 210
 211 /* --- @sha256_set@, @sha224_set@ --- *
 212  *
 213  * Arguments:   @sha256_ctx *ctx@ = pointer to context block
 214  *              @const void *buf@ = pointer to state buffer
 215  *              @unsigned long count@ = current count of bytes processed
 216  *
 217  * Returns:     ---
 218  *
 219  * Use:         Initializes a context block from a given state.  This is
 220  *              useful in cases where the initial hash state is meant to be
 221  *              secret, e.g., for NMAC and HMAC support.
 222  */
 223
 224 void sha256_set(sha256_ctx *ctx, const void *buf, unsigned long count)
 225 {
 226   const octet *p = buf;
 227   ctx->a = LOAD32(p +  0);
 228   ctx->b = LOAD32(p +  4);
 229   ctx->c = LOAD32(p +  8);
 230   ctx->d = LOAD32(p + 12);
 231   ctx->e = LOAD32(p + 16);
 232   ctx->f = LOAD32(p + 20);
 233   ctx->g = LOAD32(p + 24);
 234   ctx->h = LOAD32(p + 28);
 235   ctx->off = 0;
 236   ctx->nl = U32(count);
 237   ctx->nh = U32(((count & ~MASK32) >> 16) >> 16);
 238 }
 239
 240 /* --- @sha256_hash@, @sha224_hash@ --- *
 241  *
 242  * Arguments:   @sha256_ctx *ctx@ = pointer to context block
 243  *              @const void *buf@ = buffer of data to hash
 244  *              @size_t sz@ = size of buffer to hash
 245  *
 246  * Returns:     ---
 247  *
 248  * Use:         Hashes a buffer of data.  The buffer may be of any size and
 249  *              alignment.
 250  */
 251
 252 void sha256_hash(sha256_ctx *ctx, const void *buf, size_t sz)
 253 {
 254   HASH_BUFFER(SHA256, sha256, ctx, buf, sz);
 255 }
 256
 257 /* --- @sha256_done, @sha224_done@ --- *
 258  *
 259  * Arguments:   @sha256_ctx *ctx@ = pointer to context block
 260  *              @void *hash@ = pointer to output buffer
 261  *
 262  * Returns:     ---
 263  *
 264  * Use:         Returns the hash of the data read so far.
 265  */
 266
 267 static void final(sha256_ctx *ctx)
 268 {
 269   HASH_PAD(SHA256, sha256, ctx, 0x80, 0, 8);
 270   STORE32(ctx->buf + SHA256_BUFSZ - 8, (ctx->nl >> 29) | (ctx->nh << 3));
 271   STORE32(ctx->buf + SHA256_BUFSZ - 4, ctx->nl << 3);
 272   sha256_compress(ctx, ctx->buf);
 273 }
 274
 275 void sha256_done(sha256_ctx *ctx, void *hash)
 276 {
 277   octet *p = hash;
 278   final(ctx);
 279   STORE32(p +  0, ctx->a);
 280   STORE32(p +  4, ctx->b);
 281   STORE32(p +  8, ctx->c);
 282   STORE32(p + 12, ctx->d);
 283   STORE32(p + 16, ctx->e);
 284   STORE32(p + 20, ctx->f);
 285   STORE32(p + 24, ctx->g);
 286   STORE32(p + 28, ctx->h);
 287 }
 288
 289 void sha224_done(sha224_ctx *ctx, void *hash)
 290 {
 291   octet *p = hash;
 292   final(ctx);
 293   STORE32(p +  0, ctx->a);
 294   STORE32(p +  4, ctx->b);
 295   STORE32(p +  8, ctx->c);
 296   STORE32(p + 12, ctx->d);
 297   STORE32(p + 16, ctx->e);
 298   STORE32(p + 20, ctx->f);
 299   STORE32(p + 24, ctx->g);
 300 }
 301
 302 /* --- @sha256_state@, @sha224_state@ --- *
 303  *
 304  * Arguments:   @sha256_ctx *ctx@ = pointer to context
 305  *              @void *state@ = pointer to buffer for current state
 306  *
 307  * Returns:     Number of bytes written to the hash function so far.
 308  *
 309  * Use:         Returns the current state of the hash function such that
 310  *              it can be passed to @sha256_set@.
 311  */
 312
 313 unsigned long sha256_state(sha256_ctx *ctx, void *state)
 314 {
 315   octet *p = state;
 316   STORE32(p +  0, ctx->a);
 317   STORE32(p +  4, ctx->b);
 318   STORE32(p +  8, ctx->c);
 319   STORE32(p + 12, ctx->d);
 320   STORE32(p + 16, ctx->e);
 321   STORE32(p + 20, ctx->f);
 322   STORE32(p + 24, ctx->g);
 323   STORE32(p + 28, ctx->h);
 324   return (ctx->nl | ((ctx->nh << 16) << 16));
 325 }
 326
 327 /* --- Generic interface --- */
 328
 329 GHASH_DEF(SHA256, sha256)
 330
 331 /* --- Test code --- */
 332
 333 HASH_TEST(SHA256, sha256)
 334
 335 /*----- That's all, folks -------------------------------------------------*/