release/src/router/nettle/md5.c

   1 /* md5.c
   2  *
   3  * The MD5 hash function, described in RFC 1321.
   4  */
   5
   6 /* nettle, low-level cryptographics library
   7  *
   8  * Copyright (C) 2001 Niels Möller
   9  *
  10  * The nettle library is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU Lesser General Public License as published by
  12  * the Free Software Foundation; either version 2.1 of the License, or (at your
  13  * option) any later version.
  14  *
  15  * The nettle library is distributed in the hope that it will be useful, but
  16  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  17  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
  18  * License for more details.
  19  *
  20  * You should have received a copy of the GNU Lesser General Public License
  21  * along with the nettle library; see the file COPYING.LIB.  If not, write to
  22  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  23  * MA 02111-1301, USA.
  24  */
  25
  26 /* Based on public domain code hacked by Colin Plumb, Andrew Kuchling, and
  27  * Niels Möller. */
  28
  29 #if HAVE_CONFIG_H
  30 # include "config.h"
  31 #endif
  32
  33 #include <assert.h>
  34 #include <string.h>
  35
  36 #include "md5.h"
  37
  38 #include "macros.h"
  39 #include "nettle-write.h"
  40
  41 void
  42 md5_init(struct md5_ctx *ctx)
  43 {
  44   const uint32_t iv[_MD5_DIGEST_LENGTH] =
  45     {
  46       0x67452301,
  47       0xefcdab89,
  48       0x98badcfe,
  49       0x10325476,
  50     };
  51   memcpy(ctx->state, iv, sizeof(ctx->state));
  52   ctx->count_low = ctx->count_high = 0;
  53   ctx->index = 0;
  54 }
  55
  56 #define COMPRESS(ctx, data) (_nettle_md5_compress((ctx)->state, (data)))
  57
  58 void
  59 md5_update(struct md5_ctx *ctx,
  60            unsigned length,
  61            const uint8_t *data)
  62 {
  63   MD_UPDATE(ctx, length, data, COMPRESS, MD_INCR(ctx));
  64 }
  65
  66 void
  67 md5_digest(struct md5_ctx *ctx,
  68            unsigned length,
  69            uint8_t *digest)
  70 {
  71   uint32_t high, low;
  72
  73   assert(length <= MD5_DIGEST_SIZE);
  74
  75   MD_PAD(ctx, 8, COMPRESS);
  76
  77   /* There are 512 = 2^9 bits in one block */
  78   high = (ctx->count_high << 9) | (ctx->count_low >> 23);
  79   low = (ctx->count_low << 9) | (ctx->index << 3);
  80
  81   LE_WRITE_UINT32(ctx->block + (MD5_DATA_SIZE - 8), low);
  82   LE_WRITE_UINT32(ctx->block + (MD5_DATA_SIZE - 4), high);
  83   _nettle_md5_compress(ctx->state, ctx->block);
  84
  85   _nettle_write_le32(length, digest, ctx->state);
  86   md5_init(ctx);
  87 }