lib/libmd/md4c.c

   1 /* MD4C.C - RSA Data Security, Inc., MD4 message-digest algorithm
   2  * $FreeBSD: src/lib/libmd/md4c.c,v 1.10 2006/01/17 15:35:56 phk Exp $
   3  * $DragonFly: src/lib/libmd/md4c.c,v 1.4 2008/09/30 16:57:05 swildner 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 const unsigned char *CONST_POINTER;
  33 typedef u_int16_t UINT2;
  34 typedef u_int32_t UINT4;
  35
  36 #define PROTO_LIST(list) list
  37
  38 /* Constants for MD4Transform routine.
  39  */
  40 #define S11 3
  41 #define S12 7
  42 #define S13 11
  43 #define S14 19
  44 #define S21 3
  45 #define S22 5
  46 #define S23 9
  47 #define S24 13
  48 #define S31 3
  49 #define S32 9
  50 #define S33 11
  51 #define S34 15
  52
  53 static void MD4Transform PROTO_LIST ((UINT4 *, const unsigned char *));
  54 static void Encode PROTO_LIST
  55   ((unsigned char *, UINT4 *, unsigned int));
  56 static void Decode PROTO_LIST
  57   ((UINT4 *, const unsigned char *, unsigned int));
  58
  59 static unsigned char PADDING[64] = {
  60   0x80, 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, 0, 0, 0, 0,
  62   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
  63 };
  64
  65 /* F, G and H are basic MD4 functions.
  66  */
  67 #define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
  68 #define G(x, y, z) (((x) & (y)) | ((x) & (z)) | ((y) & (z)))
  69 #define H(x, y, z) ((x) ^ (y) ^ (z))
  70
  71 /* ROTATE_LEFT rotates x left n bits.
  72  */
  73 #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
  74
  75 /* FF, GG and HH are transformations for rounds 1, 2 and 3 */
  76 /* Rotation is separate from addition to prevent recomputation */
  77 #define FF(a, b, c, d, x, s) { \
  78     (a) += F ((b), (c), (d)) + (x); \
  79     (a) = ROTATE_LEFT ((a), (s)); \
  80   }
  81 #define GG(a, b, c, d, x, s) { \
  82     (a) += G ((b), (c), (d)) + (x) + (UINT4)0x5a827999; \
  83     (a) = ROTATE_LEFT ((a), (s)); \
  84   }
  85 #define HH(a, b, c, d, x, s) { \
  86     (a) += H ((b), (c), (d)) + (x) + (UINT4)0x6ed9eba1; \
  87     (a) = ROTATE_LEFT ((a), (s)); \
  88   }
  89
  90 /* MD4 initialization. Begins an MD4 operation, writing a new context.
  91  */
  92 int
  93 MD4Init (MD4_CTX *context)
  94 {
  95   context->Nl = context->Nh = 0;
  96
  97   /* Load magic initialization constants.
  98    */
  99   context->A = 0x67452301;
 100   context->B = 0xefcdab89;
 101   context->C = 0x98badcfe;
 102   context->D = 0x10325476;
 103   return 1;
 104 }
 105
 106 /* MD4 block update operation. Continues an MD4 message-digest
 107      operation, processing another message block, and updating the
 108      context.
 109  */
 110 void
 111 MD4Update (MD4_CTX *context, const void *in, unsigned int inputLen)
 112 {
 113   unsigned int i, idx, partLen;
 114   const unsigned char *input = in;
 115
 116   /* Compute number of bytes mod 64 */
 117   idx = (unsigned int)((context->Nl >> 3) & 0x3F);
 118   /* Update number of bits */
 119   if ((context->Nl += ((UINT4)inputLen << 3))
 120       < ((UINT4)inputLen << 3))
 121     context->Nh++;
 122   context->Nh += ((UINT4)inputLen >> 29);
 123
 124   partLen = 64 - idx;
 125   /* Transform as many times as possible.
 126    */
 127   if (inputLen >= partLen) {
 128     memcpy
 129       ((POINTER)&((char *)context->data)[idx], (CONST_POINTER)input, partLen);
 130     MD4Transform (&context->A, (unsigned char *)context->data);
 131
 132     for (i = partLen; i + 63 < inputLen; i += 64)
 133       MD4Transform (&context->A, &input[i]);
 134
 135     idx = 0;
 136   }
 137   else
 138     i = 0;
 139
 140   /* Buffer remaining input */
 141   memcpy
 142     ((POINTER)&((char *)context->data)[idx], (CONST_POINTER)&input[i],
 143      inputLen-i);
 144 }
 145
 146 /* MD4 padding. */
 147 void
 148 MD4Pad (MD4_CTX *context)
 149 {
 150   unsigned char bits[8];
 151   unsigned int idx, padLen;
 152
 153   /* Save number of bits */
 154   Encode (bits, &context->Nl, 8);
 155
 156   /* Pad out to 56 mod 64.
 157    */
 158   idx = (unsigned int)((context->Nl >> 3) & 0x3f);
 159   padLen = (idx < 56) ? (56 - idx) : (120 - idx);
 160   MD4Update (context, PADDING, padLen);
 161
 162   /* Append length (before padding) */
 163   MD4Update (context, bits, 8);
 164 }
 165
 166 /* MD4 finalization. Ends an MD4 message-digest operation, writing the
 167      the message digest and zeroizing the context.
 168  */
 169 void
 170 MD4Final (unsigned char digest[16], MD4_CTX *context)
 171 {
 172   /* Do padding */
 173   MD4Pad (context);
 174
 175   /* Store state in digest */
 176   Encode (digest, &context->A, 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
 186 MD4Transform (UINT4 *state, const unsigned char *block)
 187 {
 188   UINT4 a = state[0], b = state[1], c = state[2], d = state[3], x[16];
 189
 190   Decode (x, block, 64);
 191
 192   /* Round 1 */
 193   FF (a, b, c, d, x[ 0], S11); /* 1 */
 194   FF (d, a, b, c, x[ 1], S12); /* 2 */
 195   FF (c, d, a, b, x[ 2], S13); /* 3 */
 196   FF (b, c, d, a, x[ 3], S14); /* 4 */
 197   FF (a, b, c, d, x[ 4], S11); /* 5 */
 198   FF (d, a, b, c, x[ 5], S12); /* 6 */
 199   FF (c, d, a, b, x[ 6], S13); /* 7 */
 200   FF (b, c, d, a, x[ 7], S14); /* 8 */
 201   FF (a, b, c, d, x[ 8], S11); /* 9 */
 202   FF (d, a, b, c, x[ 9], S12); /* 10 */
 203   FF (c, d, a, b, x[10], S13); /* 11 */
 204   FF (b, c, d, a, x[11], S14); /* 12 */
 205   FF (a, b, c, d, x[12], S11); /* 13 */
 206   FF (d, a, b, c, x[13], S12); /* 14 */
 207   FF (c, d, a, b, x[14], S13); /* 15 */
 208   FF (b, c, d, a, x[15], S14); /* 16 */
 209
 210   /* Round 2 */
 211   GG (a, b, c, d, x[ 0], S21); /* 17 */
 212   GG (d, a, b, c, x[ 4], S22); /* 18 */
 213   GG (c, d, a, b, x[ 8], S23); /* 19 */
 214   GG (b, c, d, a, x[12], S24); /* 20 */
 215   GG (a, b, c, d, x[ 1], S21); /* 21 */
 216   GG (d, a, b, c, x[ 5], S22); /* 22 */
 217   GG (c, d, a, b, x[ 9], S23); /* 23 */
 218   GG (b, c, d, a, x[13], S24); /* 24 */
 219   GG (a, b, c, d, x[ 2], S21); /* 25 */
 220   GG (d, a, b, c, x[ 6], S22); /* 26 */
 221   GG (c, d, a, b, x[10], S23); /* 27 */
 222   GG (b, c, d, a, x[14], S24); /* 28 */
 223   GG (a, b, c, d, x[ 3], S21); /* 29 */
 224   GG (d, a, b, c, x[ 7], S22); /* 30 */
 225   GG (c, d, a, b, x[11], S23); /* 31 */
 226   GG (b, c, d, a, x[15], S24); /* 32 */
 227
 228   /* Round 3 */
 229   HH (a, b, c, d, x[ 0], S31); /* 33 */
 230   HH (d, a, b, c, x[ 8], S32); /* 34 */
 231   HH (c, d, a, b, x[ 4], S33); /* 35 */
 232   HH (b, c, d, a, x[12], S34); /* 36 */
 233   HH (a, b, c, d, x[ 2], S31); /* 37 */
 234   HH (d, a, b, c, x[10], S32); /* 38 */
 235   HH (c, d, a, b, x[ 6], S33); /* 39 */
 236   HH (b, c, d, a, x[14], S34); /* 40 */
 237   HH (a, b, c, d, x[ 1], S31); /* 41 */
 238   HH (d, a, b, c, x[ 9], S32); /* 42 */
 239   HH (c, d, a, b, x[ 5], S33); /* 43 */
 240   HH (b, c, d, a, x[13], S34); /* 44 */
 241   HH (a, b, c, d, x[ 3], S31); /* 45 */
 242   HH (d, a, b, c, x[11], S32); /* 46 */
 243   HH (c, d, a, b, x[ 7], S33); /* 47 */
 244   HH (b, c, d, a, x[15], S34); /* 48 */
 245
 246   state[0] += a;
 247   state[1] += b;
 248   state[2] += c;
 249   state[3] += d;
 250
 251   /* Zeroize sensitive information.
 252    */
 253   memset ((POINTER)x, 0, sizeof (x));
 254 }
 255
 256 /* Encodes input (UINT4) into output (unsigned char). Assumes len is
 257      a multiple of 4.
 258  */
 259 static void
 260 Encode (unsigned char *output, UINT4 *input, unsigned int len)
 261 {
 262   unsigned int i, j;
 263
 264   for (i = 0, j = 0; j < len; i++, j += 4) {
 265     output[j] = (unsigned char)(input[i] & 0xff);
 266     output[j+1] = (unsigned char)((input[i] >> 8) & 0xff);
 267     output[j+2] = (unsigned char)((input[i] >> 16) & 0xff);
 268     output[j+3] = (unsigned char)((input[i] >> 24) & 0xff);
 269   }
 270 }
 271
 272 /* Decodes input (unsigned char) into output (UINT4). Assumes len is
 273      a multiple of 4.
 274  */
 275 static void
 276 Decode (UINT4 *output, const unsigned char *input, unsigned int len)
 277 {
 278   unsigned int i, j;
 279
 280   for (i = 0, j = 0; j < len; i++, j += 4)
 281     output[i] = ((UINT4)input[j]) | (((UINT4)input[j+1]) << 8) |
 282       (((UINT4)input[j+2]) << 16) | (((UINT4)input[j+3]) << 24);
 283 }