release/src/router/nettle/md4.c

   1 /* md4.h
   2  *
   3  * The MD4 hash function, described in RFC 1320.
   4  */
   5
   6 /* nettle, low-level cryptographics library
   7  *
   8  * Copyright (C) 2003 Niels Möller, Marcus Comstedt
   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 the public domain md5 code, and modified by Marcus
  27    Comstedt */
  28
  29 #if HAVE_CONFIG_H
  30 # include "config.h"
  31 #endif
  32
  33 #include <assert.h>
  34 #include <string.h>
  35
  36 #include "md4.h"
  37
  38 #include "macros.h"
  39 #include "nettle-write.h"
  40
  41 /* A block, treated as a sequence of 32-bit words. */
  42 #define MD4_DATA_LENGTH 16
  43
  44 static void
  45 md4_transform(uint32_t *digest, const uint32_t *data);
  46
  47 static void
  48 md4_compress(struct md4_ctx *ctx, const uint8_t *block);
  49
  50 /* FIXME: Could be an alias for md5_init */
  51 void
  52 md4_init(struct md4_ctx *ctx)
  53 {
  54   /* Same constants as for md5. */
  55   const uint32_t iv[_MD4_DIGEST_LENGTH] =
  56     {
  57       0x67452301,
  58       0xefcdab89,
  59       0x98badcfe,
  60       0x10325476,
  61     };
  62   memcpy(ctx->state, iv, sizeof(ctx->state));
  63
  64   ctx->count_low = ctx->count_high = 0;
  65   ctx->index = 0;
  66 }
  67
  68 void
  69 md4_update(struct md4_ctx *ctx,
  70            unsigned length,
  71            const uint8_t *data)
  72 {
  73   MD_UPDATE(ctx, length, data, md4_compress, MD_INCR(ctx));
  74 }
  75
  76 void
  77 md4_digest(struct md4_ctx *ctx,
  78            unsigned length,
  79            uint8_t *digest)
  80 {
  81   uint32_t data[MD4_DATA_LENGTH];
  82   unsigned i;
  83
  84   assert(length <= MD4_DIGEST_SIZE);
  85
  86   MD_PAD(ctx, 8, md4_compress);
  87   for (i = 0; i < MD4_DATA_LENGTH - 2; i++)
  88     data[i] = LE_READ_UINT32(ctx->block + 4*i);
  89
  90   /* There are 512 = 2^9 bits in one block
  91    * Little-endian order => Least significant word first */
  92
  93   data[MD4_DATA_LENGTH-1] = (ctx->count_high << 9) | (ctx->count_low >> 23);
  94   data[MD4_DATA_LENGTH-2] = (ctx->count_low << 9) | (ctx->index << 3);
  95   md4_transform(ctx->state, data);
  96
  97   _nettle_write_le32(length, digest, ctx->state);
  98   md4_init(ctx);
  99 }
 100
 101 /* MD4 functions */
 102 #define F(x, y, z) (((y) & (x)) | ((z) & ~(x)))
 103 #define G(x, y, z) (((y) & (x)) | ((z) & (x)) | ((y) & (z)))
 104 #define H(x, y, z) ((x) ^ (y) ^ (z))
 105
 106 #define ROUND(f, w, x, y, z, data, s) \
 107 ( w += f(x, y, z) + data,  w = w<<s | w>>(32-s) )
 108
 109 /* Perform the MD4 transformation on one full block of 16 32-bit words. */
 110
 111 static void
 112 md4_transform(uint32_t *digest, const uint32_t *data)
 113 {
 114   uint32_t a, b, c, d;
 115   a = digest[0];
 116   b = digest[1];
 117   c = digest[2];
 118   d = digest[3];
 119
 120   ROUND(F, a, b, c, d, data[ 0], 3);
 121   ROUND(F, d, a, b, c, data[ 1], 7);
 122   ROUND(F, c, d, a, b, data[ 2], 11);
 123   ROUND(F, b, c, d, a, data[ 3], 19);
 124   ROUND(F, a, b, c, d, data[ 4], 3);
 125   ROUND(F, d, a, b, c, data[ 5], 7);
 126   ROUND(F, c, d, a, b, data[ 6], 11);
 127   ROUND(F, b, c, d, a, data[ 7], 19);
 128   ROUND(F, a, b, c, d, data[ 8], 3);
 129   ROUND(F, d, a, b, c, data[ 9], 7);
 130   ROUND(F, c, d, a, b, data[10], 11);
 131   ROUND(F, b, c, d, a, data[11], 19);
 132   ROUND(F, a, b, c, d, data[12], 3);
 133   ROUND(F, d, a, b, c, data[13], 7);
 134   ROUND(F, c, d, a, b, data[14], 11);
 135   ROUND(F, b, c, d, a, data[15], 19);
 136
 137   ROUND(G, a, b, c, d, data[ 0] + 0x5a827999, 3);
 138   ROUND(G, d, a, b, c, data[ 4] + 0x5a827999, 5);
 139   ROUND(G, c, d, a, b, data[ 8] + 0x5a827999, 9);
 140   ROUND(G, b, c, d, a, data[12] + 0x5a827999, 13);
 141   ROUND(G, a, b, c, d, data[ 1] + 0x5a827999, 3);
 142   ROUND(G, d, a, b, c, data[ 5] + 0x5a827999, 5);
 143   ROUND(G, c, d, a, b, data[ 9] + 0x5a827999, 9);
 144   ROUND(G, b, c, d, a, data[13] + 0x5a827999, 13);
 145   ROUND(G, a, b, c, d, data[ 2] + 0x5a827999, 3);
 146   ROUND(G, d, a, b, c, data[ 6] + 0x5a827999, 5);
 147   ROUND(G, c, d, a, b, data[10] + 0x5a827999, 9);
 148   ROUND(G, b, c, d, a, data[14] + 0x5a827999, 13);
 149   ROUND(G, a, b, c, d, data[ 3] + 0x5a827999, 3);
 150   ROUND(G, d, a, b, c, data[ 7] + 0x5a827999, 5);
 151   ROUND(G, c, d, a, b, data[11] + 0x5a827999, 9);
 152   ROUND(G, b, c, d, a, data[15] + 0x5a827999, 13);
 153
 154   ROUND(H, a, b, c, d, data[ 0] + 0x6ed9eba1, 3);
 155   ROUND(H, d, a, b, c, data[ 8] + 0x6ed9eba1, 9);
 156   ROUND(H, c, d, a, b, data[ 4] + 0x6ed9eba1, 11);
 157   ROUND(H, b, c, d, a, data[12] + 0x6ed9eba1, 15);
 158   ROUND(H, a, b, c, d, data[ 2] + 0x6ed9eba1, 3);
 159   ROUND(H, d, a, b, c, data[10] + 0x6ed9eba1, 9);
 160   ROUND(H, c, d, a, b, data[ 6] + 0x6ed9eba1, 11);
 161   ROUND(H, b, c, d, a, data[14] + 0x6ed9eba1, 15);
 162   ROUND(H, a, b, c, d, data[ 1] + 0x6ed9eba1, 3);
 163   ROUND(H, d, a, b, c, data[ 9] + 0x6ed9eba1, 9);
 164   ROUND(H, c, d, a, b, data[ 5] + 0x6ed9eba1, 11);
 165   ROUND(H, b, c, d, a, data[13] + 0x6ed9eba1, 15);
 166   ROUND(H, a, b, c, d, data[ 3] + 0x6ed9eba1, 3);
 167   ROUND(H, d, a, b, c, data[11] + 0x6ed9eba1, 9);
 168   ROUND(H, c, d, a, b, data[ 7] + 0x6ed9eba1, 11);
 169   ROUND(H, b, c, d, a, data[15] + 0x6ed9eba1, 15);
 170
 171   digest[0] += a;
 172   digest[1] += b;
 173   digest[2] += c;
 174   digest[3] += d;
 175 }
 176
 177 static void
 178 md4_compress(struct md4_ctx *ctx, const uint8_t *block)
 179 {
 180   uint32_t data[MD4_DATA_LENGTH];
 181   unsigned i;
 182
 183   /* Endian independent conversion */
 184   for (i = 0; i<16; i++, block += 4)
 185     data[i] = LE_READ_UINT32(block);
 186
 187   md4_transform(ctx->state, data);
 188 }