lib/libmd/md4c.c

   1 /* MD4C.C - RSA Data Security, Inc., MD4 message-digest algorithm
   2  * $FreeBSD: src/lib/libmd/md4c.c,v 1.7 1999/08/28 00:05:05 peter Exp $
   3  * $DragonFly: src/lib/libmd/md4c.c,v 1.2 2003/06/17 06:26:50 dillon Exp $
   4  */
   5
   6 /* Copyright (C) 1990-2, RSA Data Security, Inc. All rights reserved.
   7
   8    License to copy and use this software is granted provided that it
   9    is identified as the "RSA Data Security, Inc. MD4 Message-Digest
  10    Algorithm" in all material mentioning or referencing this software
  11    or this function.
  12
  13    License is also granted to make and use derivative works provided
  14    that such works are identified as "derived from the RSA Data
  15    Security, Inc. MD4 Message-Digest Algorithm" in all material
  16    mentioning or referencing the derived work.
  17
  18    RSA Data Security, Inc. makes no representations concerning either
  19    the merchantability of this software or the suitability of this
  20    software for any particular purpose. It is provided "as is"
  21    without express or implied warranty of any kind.
  22
  23    These notices must be retained in any copies of any part of this
  24    documentation and/or software.
  25  */
  26
  27 #include <sys/types.h>
  28 #include <string.h>
  29 #include "md4.h"
  30
  31 typedef unsigned char *POINTER;
  32 typedef u_int16_t UINT2;
  33 typedef u_int32_t UINT4;
  34
  35 #define PROTO_LIST(list) list
  36
  37 /* Constants for MD4Transform routine.
  38  */
  39 #define S11 3
  40 #define S12 7
  41 #define S13 11
  42 #define S14 19
  43 #define S21 3
  44 #define S22 5
  45 #define S23 9
  46 #define S24 13
  47 #define S31 3
  48 #define S32 9
  49 #define S33 11
  50 #define S34 15
  51
  52 static void MD4Transform PROTO_LIST ((UINT4 [4], const unsigned char [64]));
  53 static void Encode PROTO_LIST
  54   ((unsigned char *, UINT4 *, unsigned int));
  55 static void Decode PROTO_LIST
  56   ((UINT4 *, const unsigned char *, unsigned int));
  57
  58 static unsigned char PADDING[64] = {
  59   0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  60   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  61   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
  62 };
  63
  64 /* F, G and H are basic MD4 functions.
  65  */
  66 #define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
  67 #define G(x, y, z) (((x) & (y)) | ((x) & (z)) | ((y) & (z)))
  68 #define H(x, y, z) ((x) ^ (y) ^ (z))
  69
  70 /* ROTATE_LEFT rotates x left n bits.
  71  */
  72 #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
  73
  74 /* FF, GG and HH are transformations for rounds 1, 2 and 3 */
  75 /* Rotation is separate from addition to prevent recomputation */
  76 #define FF(a, b, c, d, x, s) { \
  77     (a) += F ((b), (c), (d)) + (x); \
  78     (a) = ROTATE_LEFT ((a), (s)); \
  79   }
  80 #define GG(a, b, c, d, x, s) { \
  81     (a) += G ((b), (c), (d)) + (x) + (UINT4)0x5a827999; \
  82     (a) = ROTATE_LEFT ((a), (s)); \
  83   }
  84 #define HH(a, b, c, d, x, s) { \
  85     (a) += H ((b), (c), (d)) + (x) + (UINT4)0x6ed9eba1; \
  86     (a) = ROTATE_LEFT ((a), (s)); \
  87   }
  88
  89 /* MD4 initialization. Begins an MD4 operation, writing a new context.
  90  */
  91 void MD4Init (context)
  92 MD4_CTX *context;                                        /* context */
  93 {
  94   context->count[0] = context->count[1] = 0;
  95
  96   /* Load magic initialization constants.
  97    */
  98   context->state[0] = 0x67452301;
  99   context->state[1] = 0xefcdab89;
 100   context->state[2] = 0x98badcfe;
 101   context->state[3] = 0x10325476;
 102 }
 103
 104 /* MD4 block update operation. Continues an MD4 message-digest
 105      operation, processing another message block, and updating the
 106      context.
 107  */
 108 void MD4Update (context, input, inputLen)
 109 MD4_CTX *context;                                        /* context */
 110 const unsigned char *input;                                /* input block */
 111 unsigned int inputLen;                     /* length of input block */
 112 {
 113   unsigned int i, index, partLen;
 114
 115   /* Compute number of bytes mod 64 */
 116   index = (unsigned int)((context->count[0] >> 3) & 0x3F);
 117   /* Update number of bits */
 118   if ((context->count[0] += ((UINT4)inputLen << 3))
 119       < ((UINT4)inputLen << 3))
 120     context->count[1]++;
 121   context->count[1] += ((UINT4)inputLen >> 29);
 122
 123   partLen = 64 - index;
 124   /* Transform as many times as possible.
 125    */
 126   if (inputLen >= partLen) {
 127     memcpy
 128       ((POINTER)&context->buffer[index], (POINTER)input, partLen);
 129     MD4Transform (context->state, context->buffer);
 130
 131     for (i = partLen; i + 63 < inputLen; i += 64)
 132       MD4Transform (context->state, &input[i]);
 133
 134     index = 0;
 135   }
 136   else
 137     i = 0;
 138
 139   /* Buffer remaining input */
 140   memcpy
 141     ((POINTER)&context->buffer[index], (POINTER)&input[i],
 142      inputLen-i);
 143 }
 144
 145 /* MD4 padding. */
 146 void MD4Pad (context)
 147 MD4_CTX *context;                                        /* context */
 148 {
 149   unsigned char bits[8];
 150   unsigned int index, padLen;
 151
 152   /* Save number of bits */
 153   Encode (bits, context->count, 8);
 154
 155   /* Pad out to 56 mod 64.
 156    */
 157   index = (unsigned int)((context->count[0] >> 3) & 0x3f);
 158   padLen = (index < 56) ? (56 - index) : (120 - index);
 159   MD4Update (context, PADDING, padLen);
 160
 161   /* Append length (before padding) */
 162   MD4Update (context, bits, 8);
 163 }
 164
 165 /* MD4 finalization. Ends an MD4 message-digest operation, writing the
 166      the message digest and zeroizing the context.
 167  */
 168 void MD4Final (digest, context)
 169 unsigned char digest[16];                         /* message digest */
 170 MD4_CTX *context;                                        /* context */
 171 {
 172   /* Do padding */
 173   MD4Pad (context);
 174
 175   /* Store state in digest */
 176   Encode (digest, context->state, 16);
 177
 178   /* Zeroize sensitive information.
 179    */
 180   memset ((POINTER)context, 0, sizeof (*context));
 181 }
 182
 183 /* MD4 basic transformation. Transforms state based on block.
 184  */
 185 static void MD4Transform (state, block)
 186 UINT4 state[4];
 187 const unsigned char block[64];
 188 {
 189   UINT4 a = state[0], b = state[1], c = state[2], d = state[3], x[16];
 190
 191   Decode (x, block, 64);
 192
 193   /* Round 1 */
 194   FF (a, b, c, d, x[ 0], S11); /* 1 */
 195   FF (d, a, b, c, x[ 1], S12); /* 2 */
 196   FF (c, d, a, b, x[ 2], S13); /* 3 */
 197   FF (b, c, d, a, x[ 3], S14); /* 4 */
 198   FF (a, b, c, d, x[ 4], S11); /* 5 */
 199   FF (d, a, b, c, x[ 5], S12); /* 6 */
 200   FF (c, d, a, b, x[ 6], S13); /* 7 */
 201   FF (b, c, d, a, x[ 7], S14); /* 8 */
 202   FF (a, b, c, d, x[ 8], S11); /* 9 */
 203   FF (d, a, b, c, x[ 9], S12); /* 10 */
 204   FF (c, d, a, b, x[10], S13); /* 11 */
 205   FF (b, c, d, a, x[11], S14); /* 12 */
 206   FF (a, b, c, d, x[12], S11); /* 13 */
 207   FF (d, a, b, c, x[13], S12); /* 14 */
 208   FF (c, d, a, b, x[14], S13); /* 15 */
 209   FF (b, c, d, a, x[15], S14); /* 16 */
 210
 211   /* Round 2 */
 212   GG (a, b, c, d, x[ 0], S21); /* 17 */
 213   GG (d, a, b, c, x[ 4], S22); /* 18 */
 214   GG (c, d, a, b, x[ 8], S23); /* 19 */
 215   GG (b, c, d, a, x[12], S24); /* 20 */
 216   GG (a, b, c, d, x[ 1], S21); /* 21 */
 217   GG (d, a, b, c, x[ 5], S22); /* 22 */
 218   GG (c, d, a, b, x[ 9], S23); /* 23 */
 219   GG (b, c, d, a, x[13], S24); /* 24 */
 220   GG (a, b, c, d, x[ 2], S21); /* 25 */
 221   GG (d, a, b, c, x[ 6], S22); /* 26 */
 222   GG (c, d, a, b, x[10], S23); /* 27 */
 223   GG (b, c, d, a, x[14], S24); /* 28 */
 224   GG (a, b, c, d, x[ 3], S21); /* 29 */
 225   GG (d, a, b, c, x[ 7], S22); /* 30 */
 226   GG (c, d, a, b, x[11], S23); /* 31 */
 227   GG (b, c, d, a, x[15], S24); /* 32 */
 228
 229   /* Round 3 */
 230   HH (a, b, c, d, x[ 0], S31); /* 33 */
 231   HH (d, a, b, c, x[ 8], S32); /* 34 */
 232   HH (c, d, a, b, x[ 4], S33); /* 35 */
 233   HH (b, c, d, a, x[12], S34); /* 36 */
 234   HH (a, b, c, d, x[ 2], S31); /* 37 */
 235   HH (d, a, b, c, x[10], S32); /* 38 */
 236   HH (c, d, a, b, x[ 6], S33); /* 39 */
 237   HH (b, c, d, a, x[14], S34); /* 40 */
 238   HH (a, b, c, d, x[ 1], S31); /* 41 */
 239   HH (d, a, b, c, x[ 9], S32); /* 42 */
 240   HH (c, d, a, b, x[ 5], S33); /* 43 */
 241   HH (b, c, d, a, x[13], S34); /* 44 */
 242   HH (a, b, c, d, x[ 3], S31); /* 45 */
 243   HH (d, a, b, c, x[11], S32); /* 46 */
 244   HH (c, d, a, b, x[ 7], S33); /* 47 */
 245   HH (b, c, d, a, x[15], S34); /* 48 */
 246
 247   state[0] += a;
 248   state[1] += b;
 249   state[2] += c;
 250   state[3] += d;
 251
 252   /* Zeroize sensitive information.
 253    */
 254   memset ((POINTER)x, 0, sizeof (x));
 255 }
 256
 257 /* Encodes input (UINT4) into output (unsigned char). Assumes len is
 258      a multiple of 4.
 259  */
 260 static void Encode (output, input, len)
 261 unsigned char *output;
 262 UINT4 *input;
 263 unsigned int len;
 264 {
 265   unsigned int i, j;
 266
 267   for (i = 0, j = 0; j < len; i++, j += 4) {
 268     output[j] = (unsigned char)(input[i] & 0xff);
 269     output[j+1] = (unsigned char)((input[i] >> 8) & 0xff);
 270     output[j+2] = (unsigned char)((input[i] >> 16) & 0xff);
 271     output[j+3] = (unsigned char)((input[i] >> 24) & 0xff);
 272   }
 273 }
 274
 275 /* Decodes input (unsigned char) into output (UINT4). Assumes len is
 276      a multiple of 4.
 277  */
 278 static void Decode (output, input, len)
 279
 280 UINT4 *output;
 281 const unsigned char *input;
 282 unsigned int len;
 283 {
 284   unsigned int i, j;
 285
 286   for (i = 0, j = 0; j < len; i++, j += 4)
 287     output[i] = ((UINT4)input[j]) | (((UINT4)input[j+1]) << 8) |
 288       (((UINT4)input[j+2]) << 16) | (((UINT4)input[j+3]) << 24);
 289 }