lib/sha256.c

   1 /* sha256.c - Functions to compute SHA256 and SHA224 message digest of files or
   2    memory blocks according to the NIST specification FIPS-180-2.
   3
   4    Copyright (C) 2005-2006, 2008-2017 Free Software Foundation, Inc.
   5
   6    This program is free software: you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation, either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  18
  19 /* Written by David Madore, considerably copypasting from
  20    Scott G. Miller's sha1.c
  21 */
  22
  23 #include <config.h>
  24
  25 #if HAVE_OPENSSL_SHA256
  26 # define GL_OPENSSL_INLINE _GL_EXTERN_INLINE
  27 #endif
  28 #include "sha256.h"
  29
  30 #include <stdalign.h>
  31 #include <stdint.h>
  32 #include <stdlib.h>
  33 #include <string.h>
  34
  35 #if USE_UNLOCKED_IO
  36 # include "unlocked-io.h"
  37 #endif
  38
  39 #ifdef WORDS_BIGENDIAN
  40 # define SWAP(n) (n)
  41 #else
  42 # define SWAP(n) \
  43     (((n) << 24) | (((n) & 0xff00) << 8) | (((n) >> 8) & 0xff00) | ((n) >> 24))
  44 #endif
  45
  46 #define BLOCKSIZE 32768
  47 #if BLOCKSIZE % 64 != 0
  48 # error "invalid BLOCKSIZE"
  49 #endif
  50
  51 #if ! HAVE_OPENSSL_SHA256
  52 /* This array contains the bytes used to pad the buffer to the next
  53    64-byte boundary.  */
  54 static const unsigned char fillbuf[64] = { 0x80, 0 /* , 0, 0, ...  */ };
  55
  56
  57 /*
  58   Takes a pointer to a 256 bit block of data (eight 32 bit ints) and
  59   initializes it to the start constants of the SHA256 algorithm.  This
  60   must be called before using hash in the call to sha256_hash
  61 */
  62 void
  63 sha256_init_ctx (struct sha256_ctx *ctx)
  64 {
  65   ctx->state[0] = 0x6a09e667UL;
  66   ctx->state[1] = 0xbb67ae85UL;
  67   ctx->state[2] = 0x3c6ef372UL;
  68   ctx->state[3] = 0xa54ff53aUL;
  69   ctx->state[4] = 0x510e527fUL;
  70   ctx->state[5] = 0x9b05688cUL;
  71   ctx->state[6] = 0x1f83d9abUL;
  72   ctx->state[7] = 0x5be0cd19UL;
  73
  74   ctx->total[0] = ctx->total[1] = 0;
  75   ctx->buflen = 0;
  76 }
  77
  78 void
  79 sha224_init_ctx (struct sha256_ctx *ctx)
  80 {
  81   ctx->state[0] = 0xc1059ed8UL;
  82   ctx->state[1] = 0x367cd507UL;
  83   ctx->state[2] = 0x3070dd17UL;
  84   ctx->state[3] = 0xf70e5939UL;
  85   ctx->state[4] = 0xffc00b31UL;
  86   ctx->state[5] = 0x68581511UL;
  87   ctx->state[6] = 0x64f98fa7UL;
  88   ctx->state[7] = 0xbefa4fa4UL;
  89
  90   ctx->total[0] = ctx->total[1] = 0;
  91   ctx->buflen = 0;
  92 }
  93
  94 /* Copy the value from v into the memory location pointed to by *cp,
  95    If your architecture allows unaligned access this is equivalent to
  96    * (uint32_t *) cp = v  */
  97 static void
  98 set_uint32 (char *cp, uint32_t v)
  99 {
 100   memcpy (cp, &v, sizeof v);
 101 }
 102
 103 /* Put result from CTX in first 32 bytes following RESBUF.  The result
 104    must be in little endian byte order.  */
 105 void *
 106 sha256_read_ctx (const struct sha256_ctx *ctx, void *resbuf)
 107 {
 108   int i;
 109   char *r = resbuf;
 110
 111   for (i = 0; i < 8; i++)
 112     set_uint32 (r + i * sizeof ctx->state[0], SWAP (ctx->state[i]));
 113
 114   return resbuf;
 115 }
 116
 117 void *
 118 sha224_read_ctx (const struct sha256_ctx *ctx, void *resbuf)
 119 {
 120   int i;
 121   char *r = resbuf;
 122
 123   for (i = 0; i < 7; i++)
 124     set_uint32 (r + i * sizeof ctx->state[0], SWAP (ctx->state[i]));
 125
 126   return resbuf;
 127 }
 128
 129 /* Process the remaining bytes in the internal buffer and the usual
 130    prolog according to the standard and write the result to RESBUF.  */
 131 static void
 132 sha256_conclude_ctx (struct sha256_ctx *ctx)
 133 {
 134   /* Take yet unprocessed bytes into account.  */
 135   size_t bytes = ctx->buflen;
 136   size_t size = (bytes < 56) ? 64 / 4 : 64 * 2 / 4;
 137
 138   /* Now count remaining bytes.  */
 139   ctx->total[0] += bytes;
 140   if (ctx->total[0] < bytes)
 141     ++ctx->total[1];
 142
 143   /* Put the 64-bit file length in *bits* at the end of the buffer.
 144      Use set_uint32 rather than a simple assignment, to avoid risk of
 145      unaligned access.  */
 146   set_uint32 ((char *) &ctx->buffer[size - 2],
 147               SWAP ((ctx->total[1] << 3) | (ctx->total[0] >> 29)));
 148   set_uint32 ((char *) &ctx->buffer[size - 1],
 149               SWAP (ctx->total[0] << 3));
 150
 151   memcpy (&((char *) ctx->buffer)[bytes], fillbuf, (size - 2) * 4 - bytes);
 152
 153   /* Process last bytes.  */
 154   sha256_process_block (ctx->buffer, size * 4, ctx);
 155 }
 156
 157 void *
 158 sha256_finish_ctx (struct sha256_ctx *ctx, void *resbuf)
 159 {
 160   sha256_conclude_ctx (ctx);
 161   return sha256_read_ctx (ctx, resbuf);
 162 }
 163
 164 void *
 165 sha224_finish_ctx (struct sha256_ctx *ctx, void *resbuf)
 166 {
 167   sha256_conclude_ctx (ctx);
 168   return sha224_read_ctx (ctx, resbuf);
 169 }
 170 #endif
 171
 172 /* Compute SHA256 message digest for bytes read from STREAM.  The
 173    resulting message digest number will be written into the 32 bytes
 174    beginning at RESBLOCK.  */
 175 int
 176 sha256_stream (FILE *stream, void *resblock)
 177 {
 178   struct sha256_ctx ctx;
 179   size_t sum;
 180
 181   char *buffer = malloc (BLOCKSIZE + 72);
 182   if (!buffer)
 183     return 1;
 184
 185   /* Initialize the computation context.  */
 186   sha256_init_ctx (&ctx);
 187
 188   /* Iterate over full file contents.  */
 189   while (1)
 190     {
 191       /* We read the file in blocks of BLOCKSIZE bytes.  One call of the
 192          computation function processes the whole buffer so that with the
 193          next round of the loop another block can be read.  */
 194       size_t n;
 195       sum = 0;
 196
 197       /* Read block.  Take care for partial reads.  */
 198       while (1)
 199         {
 200           n = fread (buffer + sum, 1, BLOCKSIZE - sum, stream);
 201
 202           sum += n;
 203
 204           if (sum == BLOCKSIZE)
 205             break;
 206
 207           if (n == 0)
 208             {
 209               /* Check for the error flag IFF N == 0, so that we don't
 210                  exit the loop after a partial read due to e.g., EAGAIN
 211                  or EWOULDBLOCK.  */
 212               if (ferror (stream))
 213                 {
 214                   free (buffer);
 215                   return 1;
 216                 }
 217               goto process_partial_block;
 218             }
 219
 220           /* We've read at least one byte, so ignore errors.  But always
 221              check for EOF, since feof may be true even though N > 0.
 222              Otherwise, we could end up calling fread after EOF.  */
 223           if (feof (stream))
 224             goto process_partial_block;
 225         }
 226
 227       /* Process buffer with BLOCKSIZE bytes.  Note that
 228                         BLOCKSIZE % 64 == 0
 229        */
 230       sha256_process_block (buffer, BLOCKSIZE, &ctx);
 231     }
 232
 233  process_partial_block:;
 234
 235   /* Process any remaining bytes.  */
 236   if (sum > 0)
 237     sha256_process_bytes (buffer, sum, &ctx);
 238
 239   /* Construct result in desired memory.  */
 240   sha256_finish_ctx (&ctx, resblock);
 241   free (buffer);
 242   return 0;
 243 }
 244
 245 /* FIXME: Avoid code duplication */
 246 int
 247 sha224_stream (FILE *stream, void *resblock)
 248 {
 249   struct sha256_ctx ctx;
 250   size_t sum;
 251
 252   char *buffer = malloc (BLOCKSIZE + 72);
 253   if (!buffer)
 254     return 1;
 255
 256   /* Initialize the computation context.  */
 257   sha224_init_ctx (&ctx);
 258
 259   /* Iterate over full file contents.  */
 260   while (1)
 261     {
 262       /* We read the file in blocks of BLOCKSIZE bytes.  One call of the
 263          computation function processes the whole buffer so that with the
 264          next round of the loop another block can be read.  */
 265       size_t n;
 266       sum = 0;
 267
 268       /* Read block.  Take care for partial reads.  */
 269       while (1)
 270         {
 271           n = fread (buffer + sum, 1, BLOCKSIZE - sum, stream);
 272
 273           sum += n;
 274
 275           if (sum == BLOCKSIZE)
 276             break;
 277
 278           if (n == 0)
 279             {
 280               /* Check for the error flag IFF N == 0, so that we don't
 281                  exit the loop after a partial read due to e.g., EAGAIN
 282                  or EWOULDBLOCK.  */
 283               if (ferror (stream))
 284                 {
 285                   free (buffer);
 286                   return 1;
 287                 }
 288               goto process_partial_block;
 289             }
 290
 291           /* We've read at least one byte, so ignore errors.  But always
 292              check for EOF, since feof may be true even though N > 0.
 293              Otherwise, we could end up calling fread after EOF.  */
 294           if (feof (stream))
 295             goto process_partial_block;
 296         }
 297
 298       /* Process buffer with BLOCKSIZE bytes.  Note that
 299                         BLOCKSIZE % 64 == 0
 300        */
 301       sha256_process_block (buffer, BLOCKSIZE, &ctx);
 302     }
 303
 304  process_partial_block:;
 305
 306   /* Process any remaining bytes.  */
 307   if (sum > 0)
 308     sha256_process_bytes (buffer, sum, &ctx);
 309
 310   /* Construct result in desired memory.  */
 311   sha224_finish_ctx (&ctx, resblock);
 312   free (buffer);
 313   return 0;
 314 }
 315
 316 #if ! HAVE_OPENSSL_SHA256
 317 /* Compute SHA512 message digest for LEN bytes beginning at BUFFER.  The
 318    result is always in little endian byte order, so that a byte-wise
 319    output yields to the wanted ASCII representation of the message
 320    digest.  */
 321 void *
 322 sha256_buffer (const char *buffer, size_t len, void *resblock)
 323 {
 324   struct sha256_ctx ctx;
 325
 326   /* Initialize the computation context.  */
 327   sha256_init_ctx (&ctx);
 328
 329   /* Process whole buffer but last len % 64 bytes.  */
 330   sha256_process_bytes (buffer, len, &ctx);
 331
 332   /* Put result in desired memory area.  */
 333   return sha256_finish_ctx (&ctx, resblock);
 334 }
 335
 336 void *
 337 sha224_buffer (const char *buffer, size_t len, void *resblock)
 338 {
 339   struct sha256_ctx ctx;
 340
 341   /* Initialize the computation context.  */
 342   sha224_init_ctx (&ctx);
 343
 344   /* Process whole buffer but last len % 64 bytes.  */
 345   sha256_process_bytes (buffer, len, &ctx);
 346
 347   /* Put result in desired memory area.  */
 348   return sha224_finish_ctx (&ctx, resblock);
 349 }
 350
 351 void
 352 sha256_process_bytes (const void *buffer, size_t len, struct sha256_ctx *ctx)
 353 {
 354   /* When we already have some bits in our internal buffer concatenate
 355      both inputs first.  */
 356   if (ctx->buflen != 0)
 357     {
 358       size_t left_over = ctx->buflen;
 359       size_t add = 128 - left_over > len ? len : 128 - left_over;
 360
 361       memcpy (&((char *) ctx->buffer)[left_over], buffer, add);
 362       ctx->buflen += add;
 363
 364       if (ctx->buflen > 64)
 365         {
 366           sha256_process_block (ctx->buffer, ctx->buflen & ~63, ctx);
 367
 368           ctx->buflen &= 63;
 369           /* The regions in the following copy operation cannot overlap.  */
 370           memcpy (ctx->buffer,
 371                   &((char *) ctx->buffer)[(left_over + add) & ~63],
 372                   ctx->buflen);
 373         }
 374
 375       buffer = (const char *) buffer + add;
 376       len -= add;
 377     }
 378
 379   /* Process available complete blocks.  */
 380   if (len >= 64)
 381     {
 382 #if !(_STRING_ARCH_unaligned || _STRING_INLINE_unaligned)
 383 # define UNALIGNED_P(p) ((uintptr_t) (p) % alignof (uint32_t) != 0)
 384       if (UNALIGNED_P (buffer))
 385         while (len > 64)
 386           {
 387             sha256_process_block (memcpy (ctx->buffer, buffer, 64), 64, ctx);
 388             buffer = (const char *) buffer + 64;
 389             len -= 64;
 390           }
 391       else
 392 #endif
 393         {
 394           sha256_process_block (buffer, len & ~63, ctx);
 395           buffer = (const char *) buffer + (len & ~63);
 396           len &= 63;
 397         }
 398     }
 399
 400   /* Move remaining bytes in internal buffer.  */
 401   if (len > 0)
 402     {
 403       size_t left_over = ctx->buflen;
 404
 405       memcpy (&((char *) ctx->buffer)[left_over], buffer, len);
 406       left_over += len;
 407       if (left_over >= 64)
 408         {
 409           sha256_process_block (ctx->buffer, 64, ctx);
 410           left_over -= 64;
 411           memcpy (ctx->buffer, &ctx->buffer[16], left_over);
 412         }
 413       ctx->buflen = left_over;
 414     }
 415 }
 416
 417 /* --- Code below is the primary difference between sha1.c and sha256.c --- */
 418
 419 /* SHA256 round constants */
 420 #define K(I) sha256_round_constants[I]
 421 static const uint32_t sha256_round_constants[64] = {
 422   0x428a2f98UL, 0x71374491UL, 0xb5c0fbcfUL, 0xe9b5dba5UL,
 423   0x3956c25bUL, 0x59f111f1UL, 0x923f82a4UL, 0xab1c5ed5UL,
 424   0xd807aa98UL, 0x12835b01UL, 0x243185beUL, 0x550c7dc3UL,
 425   0x72be5d74UL, 0x80deb1feUL, 0x9bdc06a7UL, 0xc19bf174UL,
 426   0xe49b69c1UL, 0xefbe4786UL, 0x0fc19dc6UL, 0x240ca1ccUL,
 427   0x2de92c6fUL, 0x4a7484aaUL, 0x5cb0a9dcUL, 0x76f988daUL,
 428   0x983e5152UL, 0xa831c66dUL, 0xb00327c8UL, 0xbf597fc7UL,
 429   0xc6e00bf3UL, 0xd5a79147UL, 0x06ca6351UL, 0x14292967UL,
 430   0x27b70a85UL, 0x2e1b2138UL, 0x4d2c6dfcUL, 0x53380d13UL,
 431   0x650a7354UL, 0x766a0abbUL, 0x81c2c92eUL, 0x92722c85UL,
 432   0xa2bfe8a1UL, 0xa81a664bUL, 0xc24b8b70UL, 0xc76c51a3UL,
 433   0xd192e819UL, 0xd6990624UL, 0xf40e3585UL, 0x106aa070UL,
 434   0x19a4c116UL, 0x1e376c08UL, 0x2748774cUL, 0x34b0bcb5UL,
 435   0x391c0cb3UL, 0x4ed8aa4aUL, 0x5b9cca4fUL, 0x682e6ff3UL,
 436   0x748f82eeUL, 0x78a5636fUL, 0x84c87814UL, 0x8cc70208UL,
 437   0x90befffaUL, 0xa4506cebUL, 0xbef9a3f7UL, 0xc67178f2UL,
 438 };
 439
 440 /* Round functions.  */
 441 #define F2(A,B,C) ( ( A & B ) | ( C & ( A | B ) ) )
 442 #define F1(E,F,G) ( G ^ ( E & ( F ^ G ) ) )
 443
 444 /* Process LEN bytes of BUFFER, accumulating context into CTX.
 445    It is assumed that LEN % 64 == 0.
 446    Most of this code comes from GnuPG's cipher/sha1.c.  */
 447
 448 void
 449 sha256_process_block (const void *buffer, size_t len, struct sha256_ctx *ctx)
 450 {
 451   const uint32_t *words = buffer;
 452   size_t nwords = len / sizeof (uint32_t);
 453   const uint32_t *endp = words + nwords;
 454   uint32_t x[16];
 455   uint32_t a = ctx->state[0];
 456   uint32_t b = ctx->state[1];
 457   uint32_t c = ctx->state[2];
 458   uint32_t d = ctx->state[3];
 459   uint32_t e = ctx->state[4];
 460   uint32_t f = ctx->state[5];
 461   uint32_t g = ctx->state[6];
 462   uint32_t h = ctx->state[7];
 463   uint32_t lolen = len;
 464
 465   /* First increment the byte count.  FIPS PUB 180-2 specifies the possible
 466      length of the file up to 2^64 bits.  Here we only compute the
 467      number of bytes.  Do a double word increment.  */
 468   ctx->total[0] += lolen;
 469   ctx->total[1] += (len >> 31 >> 1) + (ctx->total[0] < lolen);
 470
 471 #define rol(x, n) (((x) << (n)) | ((x) >> (32 - (n))))
 472 #define S0(x) (rol(x,25)^rol(x,14)^(x>>3))
 473 #define S1(x) (rol(x,15)^rol(x,13)^(x>>10))
 474 #define SS0(x) (rol(x,30)^rol(x,19)^rol(x,10))
 475 #define SS1(x) (rol(x,26)^rol(x,21)^rol(x,7))
 476
 477 #define M(I) ( tm =   S1(x[(I-2)&0x0f]) + x[(I-7)&0x0f] \
 478                     + S0(x[(I-15)&0x0f]) + x[I&0x0f]    \
 479                , x[I&0x0f] = tm )
 480
 481 #define R(A,B,C,D,E,F,G,H,K,M)  do { t0 = SS0(A) + F2(A,B,C); \
 482                                      t1 = H + SS1(E)  \
 483                                       + F1(E,F,G)     \
 484                                       + K             \
 485                                       + M;            \
 486                                      D += t1;  H = t0 + t1; \
 487                                } while(0)
 488
 489   while (words < endp)
 490     {
 491       uint32_t tm;
 492       uint32_t t0, t1;
 493       int t;
 494       /* FIXME: see sha1.c for a better implementation.  */
 495       for (t = 0; t < 16; t++)
 496         {
 497           x[t] = SWAP (*words);
 498           words++;
 499         }
 500
 501       R( a, b, c, d, e, f, g, h, K( 0), x[ 0] );
 502       R( h, a, b, c, d, e, f, g, K( 1), x[ 1] );
 503       R( g, h, a, b, c, d, e, f, K( 2), x[ 2] );
 504       R( f, g, h, a, b, c, d, e, K( 3), x[ 3] );
 505       R( e, f, g, h, a, b, c, d, K( 4), x[ 4] );
 506       R( d, e, f, g, h, a, b, c, K( 5), x[ 5] );
 507       R( c, d, e, f, g, h, a, b, K( 6), x[ 6] );
 508       R( b, c, d, e, f, g, h, a, K( 7), x[ 7] );
 509       R( a, b, c, d, e, f, g, h, K( 8), x[ 8] );
 510       R( h, a, b, c, d, e, f, g, K( 9), x[ 9] );
 511       R( g, h, a, b, c, d, e, f, K(10), x[10] );
 512       R( f, g, h, a, b, c, d, e, K(11), x[11] );
 513       R( e, f, g, h, a, b, c, d, K(12), x[12] );
 514       R( d, e, f, g, h, a, b, c, K(13), x[13] );
 515       R( c, d, e, f, g, h, a, b, K(14), x[14] );
 516       R( b, c, d, e, f, g, h, a, K(15), x[15] );
 517       R( a, b, c, d, e, f, g, h, K(16), M(16) );
 518       R( h, a, b, c, d, e, f, g, K(17), M(17) );
 519       R( g, h, a, b, c, d, e, f, K(18), M(18) );
 520       R( f, g, h, a, b, c, d, e, K(19), M(19) );
 521       R( e, f, g, h, a, b, c, d, K(20), M(20) );
 522       R( d, e, f, g, h, a, b, c, K(21), M(21) );
 523       R( c, d, e, f, g, h, a, b, K(22), M(22) );
 524       R( b, c, d, e, f, g, h, a, K(23), M(23) );
 525       R( a, b, c, d, e, f, g, h, K(24), M(24) );
 526       R( h, a, b, c, d, e, f, g, K(25), M(25) );
 527       R( g, h, a, b, c, d, e, f, K(26), M(26) );
 528       R( f, g, h, a, b, c, d, e, K(27), M(27) );
 529       R( e, f, g, h, a, b, c, d, K(28), M(28) );
 530       R( d, e, f, g, h, a, b, c, K(29), M(29) );
 531       R( c, d, e, f, g, h, a, b, K(30), M(30) );
 532       R( b, c, d, e, f, g, h, a, K(31), M(31) );
 533       R( a, b, c, d, e, f, g, h, K(32), M(32) );
 534       R( h, a, b, c, d, e, f, g, K(33), M(33) );
 535       R( g, h, a, b, c, d, e, f, K(34), M(34) );
 536       R( f, g, h, a, b, c, d, e, K(35), M(35) );
 537       R( e, f, g, h, a, b, c, d, K(36), M(36) );
 538       R( d, e, f, g, h, a, b, c, K(37), M(37) );
 539       R( c, d, e, f, g, h, a, b, K(38), M(38) );
 540       R( b, c, d, e, f, g, h, a, K(39), M(39) );
 541       R( a, b, c, d, e, f, g, h, K(40), M(40) );
 542       R( h, a, b, c, d, e, f, g, K(41), M(41) );
 543       R( g, h, a, b, c, d, e, f, K(42), M(42) );
 544       R( f, g, h, a, b, c, d, e, K(43), M(43) );
 545       R( e, f, g, h, a, b, c, d, K(44), M(44) );
 546       R( d, e, f, g, h, a, b, c, K(45), M(45) );
 547       R( c, d, e, f, g, h, a, b, K(46), M(46) );
 548       R( b, c, d, e, f, g, h, a, K(47), M(47) );
 549       R( a, b, c, d, e, f, g, h, K(48), M(48) );
 550       R( h, a, b, c, d, e, f, g, K(49), M(49) );
 551       R( g, h, a, b, c, d, e, f, K(50), M(50) );
 552       R( f, g, h, a, b, c, d, e, K(51), M(51) );
 553       R( e, f, g, h, a, b, c, d, K(52), M(52) );
 554       R( d, e, f, g, h, a, b, c, K(53), M(53) );
 555       R( c, d, e, f, g, h, a, b, K(54), M(54) );
 556       R( b, c, d, e, f, g, h, a, K(55), M(55) );
 557       R( a, b, c, d, e, f, g, h, K(56), M(56) );
 558       R( h, a, b, c, d, e, f, g, K(57), M(57) );
 559       R( g, h, a, b, c, d, e, f, K(58), M(58) );
 560       R( f, g, h, a, b, c, d, e, K(59), M(59) );
 561       R( e, f, g, h, a, b, c, d, K(60), M(60) );
 562       R( d, e, f, g, h, a, b, c, K(61), M(61) );
 563       R( c, d, e, f, g, h, a, b, K(62), M(62) );
 564       R( b, c, d, e, f, g, h, a, K(63), M(63) );
 565
 566       a = ctx->state[0] += a;
 567       b = ctx->state[1] += b;
 568       c = ctx->state[2] += c;
 569       d = ctx->state[3] += d;
 570       e = ctx->state[4] += e;
 571       f = ctx->state[5] += f;
 572       g = ctx->state[6] += g;
 573       h = ctx->state[7] += h;
 574     }
 575 }
 576 #endif