1: /* Functions to compute SHA512 message digest of files or memory blocks.
    2:    according to the definition of SHA512 in FIPS 180-2.
    3:    Copyright (C) 2007 Free Software Foundation, Inc.
    4:    This file is part of the GNU C Library.
    5: 
    6:    The GNU C Library is free software; you can redistribute it and/or
    7:    modify it under the terms of the GNU Lesser General Public
    8:    License as published by the Free Software Foundation; either
    9:    version 2.1 of the License, or (at your option) any later version.
   10: 
   11:    The GNU C Library 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 GNU
   14:    Lesser General Public License for more details.
   15: 
   16:    You should have received a copy of the GNU Lesser General Public
   17:    License along with the GNU C Library; if not, write to the Free
   18:    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   19:    02111-1307 USA.  */
   20: 
   21: /* Written by Ulrich Drepper <drepper@redhat.com>, 2007.  */
   22: 
   23: #ifdef HAVE_CONFIG_H
   24: # include <config.h>
   25: #endif
   26: 
   27: #include <endian.h>
   28: #include <stdlib.h>
   29: #include <string.h>
   30: #include <sys/types.h>
   31: 
   32: #include "sha512.h"
   33: 
   34: #if __BYTE_ORDER == __LITTLE_ENDIAN
   35: # ifdef _LIBC
   36: #  include <byteswap.h>
   37: #  define SWAP(n) bswap_64 (n)
   38: # else
   39: #  define SWAP(n) \
   40:   (((n) << 56)                                  \
   41:    | (((n) & 0xff00) << 40)                     \
   42:    | (((n) & 0xff0000) << 24)                   \
   43:    | (((n) & 0xff000000) << 8)                  \
   44:    | (((n) >> 8) & 0xff000000)                  \
   45:    | (((n) >> 24) & 0xff0000)                   \
   46:    | (((n) >> 40) & 0xff00)                     \
   47:    | ((n) >> 56))
   48: # endif
   49: #else
   50: # define SWAP(n) (n)
   51: #endif
   52: 
   53: 
   54: /* This array contains the bytes used to pad the buffer to the next
   55:    64-byte boundary.  (FIPS 180-2:5.1.2)  */
   56: static const unsigned char fillbuf[128] = { 0x80, 0 /* , 0, 0, ...  */ };
   57: 
   58: 
   59: /* Constants for SHA512 from FIPS 180-2:4.2.3.  */
   60: static const uint64_t K[80] =
   61:   {
   62:     UINT64_C (0x428a2f98d728ae22), UINT64_C (0x7137449123ef65cd),
   63:     UINT64_C (0xb5c0fbcfec4d3b2f), UINT64_C (0xe9b5dba58189dbbc),
   64:     UINT64_C (0x3956c25bf348b538), UINT64_C (0x59f111f1b605d019),
   65:     UINT64_C (0x923f82a4af194f9b), UINT64_C (0xab1c5ed5da6d8118),
   66:     UINT64_C (0xd807aa98a3030242), UINT64_C (0x12835b0145706fbe),
   67:     UINT64_C (0x243185be4ee4b28c), UINT64_C (0x550c7dc3d5ffb4e2),
   68:     UINT64_C (0x72be5d74f27b896f), UINT64_C (0x80deb1fe3b1696b1),
   69:     UINT64_C (0x9bdc06a725c71235), UINT64_C (0xc19bf174cf692694),
   70:     UINT64_C (0xe49b69c19ef14ad2), UINT64_C (0xefbe4786384f25e3),
   71:     UINT64_C (0x0fc19dc68b8cd5b5), UINT64_C (0x240ca1cc77ac9c65),
   72:     UINT64_C (0x2de92c6f592b0275), UINT64_C (0x4a7484aa6ea6e483),
   73:     UINT64_C (0x5cb0a9dcbd41fbd4), UINT64_C (0x76f988da831153b5),
   74:     UINT64_C (0x983e5152ee66dfab), UINT64_C (0xa831c66d2db43210),
   75:     UINT64_C (0xb00327c898fb213f), UINT64_C (0xbf597fc7beef0ee4),
   76:     UINT64_C (0xc6e00bf33da88fc2), UINT64_C (0xd5a79147930aa725),
   77:     UINT64_C (0x06ca6351e003826f), UINT64_C (0x142929670a0e6e70),
   78:     UINT64_C (0x27b70a8546d22ffc), UINT64_C (0x2e1b21385c26c926),
   79:     UINT64_C (0x4d2c6dfc5ac42aed), UINT64_C (0x53380d139d95b3df),
   80:     UINT64_C (0x650a73548baf63de), UINT64_C (0x766a0abb3c77b2a8),
   81:     UINT64_C (0x81c2c92e47edaee6), UINT64_C (0x92722c851482353b),
   82:     UINT64_C (0xa2bfe8a14cf10364), UINT64_C (0xa81a664bbc423001),
   83:     UINT64_C (0xc24b8b70d0f89791), UINT64_C (0xc76c51a30654be30),
   84:     UINT64_C (0xd192e819d6ef5218), UINT64_C (0xd69906245565a910),
   85:     UINT64_C (0xf40e35855771202a), UINT64_C (0x106aa07032bbd1b8),
   86:     UINT64_C (0x19a4c116b8d2d0c8), UINT64_C (0x1e376c085141ab53),
   87:     UINT64_C (0x2748774cdf8eeb99), UINT64_C (0x34b0bcb5e19b48a8),
   88:     UINT64_C (0x391c0cb3c5c95a63), UINT64_C (0x4ed8aa4ae3418acb),
   89:     UINT64_C (0x5b9cca4f7763e373), UINT64_C (0x682e6ff3d6b2b8a3),
   90:     UINT64_C (0x748f82ee5defb2fc), UINT64_C (0x78a5636f43172f60),
   91:     UINT64_C (0x84c87814a1f0ab72), UINT64_C (0x8cc702081a6439ec),
   92:     UINT64_C (0x90befffa23631e28), UINT64_C (0xa4506cebde82bde9),
   93:     UINT64_C (0xbef9a3f7b2c67915), UINT64_C (0xc67178f2e372532b),
   94:     UINT64_C (0xca273eceea26619c), UINT64_C (0xd186b8c721c0c207),
   95:     UINT64_C (0xeada7dd6cde0eb1e), UINT64_C (0xf57d4f7fee6ed178),
   96:     UINT64_C (0x06f067aa72176fba), UINT64_C (0x0a637dc5a2c898a6),
   97:     UINT64_C (0x113f9804bef90dae), UINT64_C (0x1b710b35131c471b),
   98:     UINT64_C (0x28db77f523047d84), UINT64_C (0x32caab7b40c72493),
   99:     UINT64_C (0x3c9ebe0a15c9bebc), UINT64_C (0x431d67c49c100d4c),
  100:     UINT64_C (0x4cc5d4becb3e42b6), UINT64_C (0x597f299cfc657e2a),
  101:     UINT64_C (0x5fcb6fab3ad6faec), UINT64_C (0x6c44198c4a475817)
  102:   };
  103: 
  104: 
  105: /* Process LEN bytes of BUFFER, accumulating context into CTX.
  106:    It is assumed that LEN % 128 == 0.  */
  107: static void
  108: sha512_process_block (const void *buffer, size_t len, struct sha512_ctx *ctx)
  109: {
  110:   const uint64_t *words = buffer;
  111:   size_t nwords = len / sizeof (uint64_t);
  112:   uint64_t a = ctx->H[0];
  113:   uint64_t b = ctx->H[1];
  114:   uint64_t c = ctx->H[2];
  115:   uint64_t d = ctx->H[3];
  116:   uint64_t e = ctx->H[4];
  117:   uint64_t f = ctx->H[5];
  118:   uint64_t g = ctx->H[6];
  119:   uint64_t h = ctx->H[7];
  120: 
  121:   /* First increment the byte count.  FIPS 180-2 specifies the possible
  122:      length of the file up to 2^128 bits.  Here we only compute the
  123:      number of bytes.  Do a double word increment.  */
  124:   ctx->total[0] += len;
  125:   if (ctx->total[0] < len)
  126:     ++ctx->total[1];
  127: 
  128:   /* Process all bytes in the buffer with 128 bytes in each round of
  129:      the loop.  */
  130:   while (nwords > 0)
  131:     {
  132:       uint64_t W[80];
  133:       uint64_t a_save = a;
  134:       uint64_t b_save = b;
  135:       uint64_t c_save = c;
  136:       uint64_t d_save = d;
  137:       uint64_t e_save = e;
  138:       uint64_t f_save = f;
  139:       uint64_t g_save = g;
  140:       uint64_t h_save = h;
  141: 
  142:       /* Operators defined in FIPS 180-2:4.1.2.  */
  143: #define Ch(x, y, z) ((x & y) ^ (~x & z))
  144: #define Maj(x, y, z) ((x & y) ^ (x & z) ^ (y & z))
  145: #define S0(x) (CYCLIC (x, 28) ^ CYCLIC (x, 34) ^ CYCLIC (x, 39))
  146: #define S1(x) (CYCLIC (x, 14) ^ CYCLIC (x, 18) ^ CYCLIC (x, 41))
  147: #define R0(x) (CYCLIC (x, 1) ^ CYCLIC (x, 8) ^ (x >> 7))
  148: #define R1(x) (CYCLIC (x, 19) ^ CYCLIC (x, 61) ^ (x >> 6))
  149: 
  150:       /* It is unfortunate that C does not provide an operator for
  151:          cyclic rotation.  Hope the C compiler is smart enough.  */
  152: #define CYCLIC(w, s) ((w >> s) | (w << (64 - s)))
  153: 
  154:       /* Compute the message schedule according to FIPS 180-2:6.3.2 step 2.  */
  155:       for (unsigned int t = 0; t < 16; ++t)
  156:         {
  157:           W[t] = SWAP (*words);
  158:           ++words;
  159:         }
  160:       for (unsigned int t = 16; t < 80; ++t)
  161:         W[t] = R1 (W[t - 2]) + W[t - 7] + R0 (W[t - 15]) + W[t - 16];
  162: 
  163:       /* The actual computation according to FIPS 180-2:6.3.2 step 3.  */
  164:       for (unsigned int t = 0; t < 80; ++t)
  165:         {
  166:           uint64_t T1 = h + S1 (e) + Ch (e, f, g) + K[t] + W[t];
  167:           uint64_t T2 = S0 (a) + Maj (a, b, c);
  168:           h = g;
  169:           g = f;
  170:           f = e;
  171:           e = d + T1;
  172:           d = c;
  173:           c = b;
  174:           b = a;
  175:           a = T1 + T2;
  176:         }
  177: 
  178:       /* Add the starting values of the context according to FIPS 180-2:6.3.2
  179:          step 4.  */
  180:       a += a_save;
  181:       b += b_save;
  182:       c += c_save;
  183:       d += d_save;
  184:       e += e_save;
  185:       f += f_save;
  186:       g += g_save;
  187:       h += h_save;
  188: 
  189:       /* Prepare for the next round.  */
  190:       nwords -= 16;
  191:     }
  192: 
  193:   /* Put checksum in context given as argument.  */
  194:   ctx->H[0] = a;
  195:   ctx->H[1] = b;
  196:   ctx->H[2] = c;
  197:   ctx->H[3] = d;
  198:   ctx->H[4] = e;
  199:   ctx->H[5] = f;
  200:   ctx->H[6] = g;
  201:   ctx->H[7] = h;
  202: }
  203: 
  204: 
  205: /* Initialize structure containing state of computation.
  206:    (FIPS 180-2:5.3.3)  */
  207: void
  208: __sha512_init_ctx (ctx)
  209:      struct sha512_ctx *ctx;
  210: {
  211:   ctx->H[0] = UINT64_C (0x6a09e667f3bcc908);
  212:   ctx->H[1] = UINT64_C (0xbb67ae8584caa73b);
  213:   ctx->H[2] = UINT64_C (0x3c6ef372fe94f82b);
  214:   ctx->H[3] = UINT64_C (0xa54ff53a5f1d36f1);
  215:   ctx->H[4] = UINT64_C (0x510e527fade682d1);
  216:   ctx->H[5] = UINT64_C (0x9b05688c2b3e6c1f);
  217:   ctx->H[6] = UINT64_C (0x1f83d9abfb41bd6b);
  218:   ctx->H[7] = UINT64_C (0x5be0cd19137e2179);
  219: 
  220:   ctx->total[0] = ctx->total[1] = 0;
  221:   ctx->buflen = 0;
  222: }
  223: 
  224: 
  225: /* Process the remaining bytes in the internal buffer and the usual
  226:    prolog according to the standard and write the result to RESBUF.
  227: 
  228:    IMPORTANT: On some systems it is required that RESBUF is correctly
  229:    aligned for a 32 bits value.  */
  230: void *
  231: __sha512_finish_ctx (ctx, resbuf)
  232:      struct sha512_ctx *ctx;
  233:      void *resbuf;
  234: {
  235:   /* Take yet unprocessed bytes into account.  */
  236:   uint64_t bytes = ctx->buflen;
  237:   size_t pad;
  238: 
  239:   /* Now count remaining bytes.  */
  240:   ctx->total[0] += bytes;
  241:   if (ctx->total[0] < bytes)
  242:     ++ctx->total[1];
  243: 
  244:   pad = bytes >= 112 ? 128 + 112 - bytes : 112 - bytes;
  245:   memcpy (&ctx->buffer[bytes], fillbuf, pad);
  246: 
  247:   /* Put the 128-bit file length in *bits* at the end of the buffer.  */
  248:   *(uint64_t *) &ctx->buffer[bytes + pad + 8] = SWAP (ctx->total[0] << 3);
  249:   *(uint64_t *) &ctx->buffer[bytes + pad] = SWAP ((ctx->total[1] << 3) |
  250:                                                   (ctx->total[0] >> 61));
  251: 
  252:   /* Process last bytes.  */
  253:   sha512_process_block (ctx->buffer, bytes + pad + 16, ctx);
  254: 
  255:   /* Put result from CTX in first 64 bytes following RESBUF.  */
  256:   for (unsigned int i = 0; i < 8; ++i)
  257:     ((uint64_t *) resbuf)[i] = SWAP (ctx->H[i]);
  258: 
  259:   return resbuf;
  260: }
  261: 
  262: 
  263: void
  264: __sha512_process_bytes (buffer, len, ctx)
  265:      const void *buffer;
  266:      size_t len;
  267:      struct sha512_ctx *ctx;
  268: {
  269:   /* When we already have some bits in our internal buffer concatenate
  270:      both inputs first.  */
  271:   if (ctx->buflen != 0)
  272:     {
  273:       size_t left_over = ctx->buflen;
  274:       size_t add = 256 - left_over > len ? len : 256 - left_over;
  275: 
  276:       memcpy (&ctx->buffer[left_over], buffer, add);
  277:       ctx->buflen += add;
  278: 
  279:       if (ctx->buflen > 128)
  280:         {
  281:           sha512_process_block (ctx->buffer, ctx->buflen & ~127, ctx);
  282: 
  283:           ctx->buflen &= 127;
  284:           /* The regions in the following copy operation cannot overlap.  */
  285:           memcpy (ctx->buffer, &ctx->buffer[(left_over + add) & ~127],
  286:                   ctx->buflen);
  287:         }
  288: 
  289:       buffer = (const char *) buffer + add;
  290:       len -= add;
  291:     }
  292: 
  293:   /* Process available complete blocks.  */
  294:   if (len >= 128)
  295:     {
  296: #if !_STRING_ARCH_unaligned
  297: /* To check alignment gcc has an appropriate operator.  Other
  298:    compilers don't.  */
  299: # if __GNUC__ >= 2
  300: #  define UNALIGNED_P(p) (((uintptr_t) p) % __alignof__ (uint64_t) != 0)
  301: # else
  302: #  define UNALIGNED_P(p) (((uintptr_t) p) % sizeof (uint64_t) != 0)
  303: # endif
  304:       if (UNALIGNED_P (buffer))
  305:         while (len > 128)
  306:           {
  307:             sha512_process_block (memcpy (ctx->buffer, buffer, 128), 128,
  308:                                     ctx);
  309:             buffer = (const char *) buffer + 128;
  310:             len -= 128;
  311:           }
  312:       else
  313: #endif
  314:         {
  315:           sha512_process_block (buffer, len & ~127, ctx);
  316:           buffer = (const char *) buffer + (len & ~127);
  317:           len &= 127;
  318:         }
  319:     }
  320: 
  321:   /* Move remaining bytes into internal buffer.  */
  322:   if (len > 0)
  323:     {
  324:       size_t left_over = ctx->buflen;
  325: 
  326:       memcpy (&ctx->buffer[left_over], buffer, len);
  327:       left_over += len;
  328:       if (left_over >= 128)
  329:         {
  330:           sha512_process_block (ctx->buffer, 128, ctx);
  331:           left_over -= 128;
  332:           memcpy (ctx->buffer, &ctx->buffer[128], left_over);
  333:         }
  334:       ctx->buflen = left_over;
  335:     }
  336: }