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 [4], const unsigned char [64]));
  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 void
  93 MD4Init (MD4_CTX *context)
  94 {
  95   context->count[0] = context->count[1] = 0;
  96
  97   /* Load magic initialization constants.
  98    */
  99   context->state[0] = 0x67452301;
 100   context->state[1] = 0xefcdab89;
 101   context->state[2] = 0x98badcfe;
 102   context->state[3] = 0x10325476;
 103 }
 104
 105 /* MD4 block update operation. Continues an MD4 message-digest
 106      operation, processing another message block, and updating the
 107      context.
 108  */
 109 void
 110 MD4Update (MD4_CTX *context, const void *in, unsigned int inputLen)
 111 {
 112   unsigned int i, idx, partLen;
 113   const unsigned char *input = in;
 114
 115   /* Compute number of bytes mod 64 */
 116   idx = (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 - idx;
 124   /* Transform as many times as possible.
 125    */
 126   if (inputLen >= partLen) {
 127     memcpy
 128       ((POINTER)&context->buffer[idx], (CONST_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     idx = 0;
 135   }
 136   else
 137     i = 0;
 138
 139   /* Buffer remaining input */
 140   memcpy
 141     ((POINTER)&context->buffer[idx], (CONST_POINTER)&input[i],
 142      inputLen-i);
 143 }
 144
 145 /* MD4 padding. */
 146 void
 147 MD4Pad (MD4_CTX *context)
 148 {
 149   unsigned char bits[8];
 150   unsigned int idx, padLen;
 151
 152   /* Save number of bits */
 153   Encode (bits, context->count, 8);
 154
 155   /* Pad out to 56 mod 64.
 156    */
 157   idx = (unsigned int)((context->count[0] >> 3) & 0x3f);
 158   padLen = (idx < 56) ? (56 - idx) : (120 - idx);
 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
 169 MD4Final (unsigned char digest[16], MD4_CTX *context)
 170 {
 171   /* Do padding */
 172   MD4Pad (context);
 173
 174   /* Store state in digest */
 175   Encode (digest, context->state, 16);
 176
 177   /* Zeroize sensitive information.
 178    */
 179   memset ((POINTER)context, 0, sizeof (*context));
 180 }
 181
 182 /* MD4 basic transformation. Transforms state based on block.
 183  */
 184 static void
 185 MD4Transform (UINT4 state[4], const unsigned char block[64])
 186 {
 187   UINT4 a = state[0], b = state[1], c = state[2], d = state[3], x[16];
 188
 189   Decode (x, block, 64);
 190
 191   /* Round 1 */
 192   FF (a, b, c, d, x[ 0], S11); /* 1 */
 193   FF (d, a, b, c, x[ 1], S12); /* 2 */
 194   FF (c, d, a, b, x[ 2], S13); /* 3 */
 195   FF (b, c, d, a, x[ 3], S14); /* 4 */
 196   FF (a, b, c, d, x[ 4], S11); /* 5 */
 197   FF (d, a, b, c, x[ 5], S12); /* 6 */
 198   FF (c, d, a, b, x[ 6], S13); /* 7 */
 199   FF (b, c, d, a, x[ 7], S14); /* 8 */
 200   FF (a, b, c, d, x[ 8], S11); /* 9 */
 201   FF (d, a, b, c, x[ 9], S12); /* 10 */
 202   FF (c, d, a, b, x[10], S13); /* 11 */
 203   FF (b, c, d, a, x[11], S14); /* 12 */
 204   FF (a, b, c, d, x[12], S11); /* 13 */
 205   FF (d, a, b, c, x[13], S12); /* 14 */
 206   FF (c, d, a, b, x[14], S13); /* 15 */
 207   FF (b, c, d, a, x[15], S14); /* 16 */
 208
 209   /* Round 2 */
 210   GG (a, b, c, d, x[ 0], S21); /* 17 */
 211   GG (d, a, b, c, x[ 4], S22); /* 18 */
 212   GG (c, d, a, b, x[ 8], S23); /* 19 */
 213   GG (b, c, d, a, x[12], S24); /* 20 */
 214   GG (a, b, c, d, x[ 1], S21); /* 21 */
 215   GG (d, a, b, c, x[ 5], S22); /* 22 */
 216   GG (c, d, a, b, x[ 9], S23); /* 23 */
 217   GG (b, c, d, a, x[13], S24); /* 24 */
 218   GG (a, b, c, d, x[ 2], S21); /* 25 */
 219   GG (d, a, b, c, x[ 6], S22); /* 26 */
 220   GG (c, d, a, b, x[10], S23); /* 27 */
 221   GG (b, c, d, a, x[14], S24); /* 28 */
 222   GG (a, b, c, d, x[ 3], S21); /* 29 */
 223   GG (d, a, b, c, x[ 7], S22); /* 30 */
 224   GG (c, d, a, b, x[11], S23); /* 31 */
 225   GG (b, c, d, a, x[15], S24); /* 32 */
 226
 227   /* Round 3 */
 228   HH (a, b, c, d, x[ 0], S31); /* 33 */
 229   HH (d, a, b, c, x[ 8], S32); /* 34 */
 230   HH (c, d, a, b, x[ 4], S33); /* 35 */
 231   HH (b, c, d, a, x[12], S34); /* 36 */
 232   HH (a, b, c, d, x[ 2], S31); /* 37 */
 233   HH (d, a, b, c, x[10], S32); /* 38 */
 234   HH (c, d, a, b, x[ 6], S33); /* 39 */
 235   HH (b, c, d, a, x[14], S34); /* 40 */
 236   HH (a, b, c, d, x[ 1], S31); /* 41 */
 237   HH (d, a, b, c, x[ 9], S32); /* 42 */
 238   HH (c, d, a, b, x[ 5], S33); /* 43 */
 239   HH (b, c, d, a, x[13], S34); /* 44 */
 240   HH (a, b, c, d, x[ 3], S31); /* 45 */
 241   HH (d, a, b, c, x[11], S32); /* 46 */
 242   HH (c, d, a, b, x[ 7], S33); /* 47 */
 243   HH (b, c, d, a, x[15], S34); /* 48 */
 244
 245   state[0] += a;
 246   state[1] += b;
 247   state[2] += c;
 248   state[3] += d;
 249
 250   /* Zeroize sensitive information.
 251    */
 252   memset ((POINTER)x, 0, sizeof (x));
 253 }
 254
 255 /* Encodes input (UINT4) into output (unsigned char). Assumes len is
 256      a multiple of 4.
 257  */
 258 static void
 259 Encode (unsigned char *output, UINT4 *input, unsigned int len)
 260 {
 261   unsigned int i, j;
 262
 263   for (i = 0, j = 0; j < len; i++, j += 4) {
 264     output[j] = (unsigned char)(input[i] & 0xff);
 265     output[j+1] = (unsigned char)((input[i] >> 8) & 0xff);
 266     output[j+2] = (unsigned char)((input[i] >> 16) & 0xff);
 267     output[j+3] = (unsigned char)((input[i] >> 24) & 0xff);
 268   }
 269 }
 270
 271 /* Decodes input (unsigned char) into output (UINT4). Assumes len is
 272      a multiple of 4.
 273  */
 274 static void
 275 Decode (UINT4 *output, const unsigned char *input, unsigned int len)
 276 {
 277   unsigned int i, j;
 278
 279   for (i = 0, j = 0; j < len; i++, j += 4)
 280     output[i] = ((UINT4)input[j]) | (((UINT4)input[j+1]) << 8) |
 281       (((UINT4)input[j+2]) << 16) | (((UINT4)input[j+3]) << 24);
 282 }