sys/kern/md4c.c

   1 /* MD4C.C - RSA Data Security, Inc., MD4 message-digest algorithm
   2  * $FreeBSD: src/sys/kern/md4c.c,v 1.1.2.1 2001/05/22 08:32:32 bp Exp $
   3  */
   4
   5 /* Copyright (C) 1990-2, RSA Data Security, Inc. All rights reserved.
   6
   7    License to copy and use this software is granted provided that it
   8    is identified as the "RSA Data Security, Inc. MD4 Message-Digest
   9    Algorithm" in all material mentioning or referencing this software
  10    or this function.
  11
  12    License is also granted to make and use derivative works provided
  13    that such works are identified as "derived from the RSA Data
  14    Security, Inc. MD4 Message-Digest Algorithm" in all material
  15    mentioning or referencing the derived work.
  16
  17    RSA Data Security, Inc. makes no representations concerning either
  18    the merchantability of this software or the suitability of this
  19    software for any particular purpose. It is provided "as is"
  20    without express or implied warranty of any kind.
  21
  22    These notices must be retained in any copies of any part of this
  23    documentation and/or software.
  24  */
  25
  26 #include <sys/param.h>
  27 #include <sys/systm.h>
  28 #include <sys/md4.h>
  29
  30 typedef unsigned char *POINTER;
  31 typedef u_int16_t UINT2;
  32 typedef u_int32_t UINT4;
  33
  34
  35 /* Constants for MD4Transform routine.
  36  */
  37 #define S11 3
  38 #define S12 7
  39 #define S13 11
  40 #define S14 19
  41 #define S21 3
  42 #define S22 5
  43 #define S23 9
  44 #define S24 13
  45 #define S31 3
  46 #define S32 9
  47 #define S33 11
  48 #define S34 15
  49
  50 static void __kern__MD4Transform(UINT4 [4], const unsigned char [64]);
  51 static void Encode(unsigned char *, UINT4 *, unsigned int);
  52 static void Decode(UINT4 *, const unsigned char *, unsigned int);
  53
  54 static unsigned char PADDING[64] = {
  55   0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  56   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  57   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
  58 };
  59
  60 /* F, G and H are basic MD4 functions.
  61  */
  62 #define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
  63 #define G(x, y, z) (((x) & (y)) | ((x) & (z)) | ((y) & (z)))
  64 #define H(x, y, z) ((x) ^ (y) ^ (z))
  65
  66 /* ROTATE_LEFT rotates x left n bits.
  67  */
  68 #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
  69
  70 /* FF, GG and HH are transformations for rounds 1, 2 and 3 */
  71 /* Rotation is separate from addition to prevent recomputation */
  72 #define FF(a, b, c, d, x, s) { \
  73     (a) += F ((b), (c), (d)) + (x); \
  74     (a) = ROTATE_LEFT ((a), (s)); \
  75   }
  76 #define GG(a, b, c, d, x, s) { \
  77     (a) += G ((b), (c), (d)) + (x) + (UINT4)0x5a827999; \
  78     (a) = ROTATE_LEFT ((a), (s)); \
  79   }
  80 #define HH(a, b, c, d, x, s) { \
  81     (a) += H ((b), (c), (d)) + (x) + (UINT4)0x6ed9eba1; \
  82     (a) = ROTATE_LEFT ((a), (s)); \
  83   }
  84
  85 /* MD4 initialization. Begins an MD4 operation, writing a new context.
  86  */
  87 void
  88 MD4Init(MD4_CTX *context)
  89 {
  90   context->count[0] = context->count[1] = 0;
  91
  92   /* Load magic initialization constants.
  93    */
  94   context->state[0] = 0x67452301;
  95   context->state[1] = 0xefcdab89;
  96   context->state[2] = 0x98badcfe;
  97   context->state[3] = 0x10325476;
  98 }
  99
 100 /* MD4 block update operation. Continues an MD4 message-digest
 101  *    operation, processing another message block, and updating the
 102  *    context.
 103  *
 104  * Parameters:
 105  *      input:          input block
 106  *      inputLen:       length of input block
 107  */
 108 void
 109 MD4Update(MD4_CTX *context, const unsigned char *input, unsigned int inputLen)
 110 {
 111   unsigned int i, index, partLen;
 112
 113   /* Compute number of bytes mod 64 */
 114   index = (unsigned int)((context->count[0] >> 3) & 0x3F);
 115   /* Update number of bits */
 116   if ((context->count[0] += ((UINT4)inputLen << 3))
 117       < ((UINT4)inputLen << 3))
 118     context->count[1]++;
 119   context->count[1] += ((UINT4)inputLen >> 29);
 120
 121   partLen = 64 - index;
 122   /* Transform as many times as possible.
 123    */
 124   if (inputLen >= partLen) {
 125     bcopy(input, &context->buffer[index], partLen);
 126     __kern__MD4Transform (context->state, context->buffer);
 127
 128     for (i = partLen; i + 63 < inputLen; i += 64)
 129       __kern__MD4Transform (context->state, &input[i]);
 130
 131     index = 0;
 132   }
 133   else
 134     i = 0;
 135
 136   /* Buffer remaining input */
 137   bcopy(&input[i], &context->buffer[index], inputLen-i);
 138 }
 139
 140 /* MD4 padding. */
 141 static void
 142 __kern__MD4Pad(MD4_CTX *context)
 143 {
 144   unsigned char bits[8];
 145   unsigned int index, padLen;
 146
 147   /* Save number of bits */
 148   Encode (bits, context->count, 8);
 149
 150   /* Pad out to 56 mod 64.
 151    */
 152   index = (unsigned int)((context->count[0] >> 3) & 0x3f);
 153   padLen = (index < 56) ? (56 - index) : (120 - index);
 154   MD4Update (context, PADDING, padLen);
 155
 156   /* Append length (before padding) */
 157   MD4Update (context, bits, 8);
 158 }
 159
 160 /* MD4 finalization. Ends an MD4 message-digest operation, writing the
 161  *    the message digest and zeroizing the context.
 162  *
 163  * Parameters:
 164  *      digest: message digest
 165  */
 166 void
 167 MD4Final(unsigned char digest[16], MD4_CTX *context)
 168 {
 169   /* Do padding */
 170   __kern__MD4Pad (context);
 171
 172   /* Store state in digest */
 173   Encode (digest, context->state, 16);
 174
 175   /* Zeroize sensitive information.
 176    */
 177   bzero((POINTER)context, sizeof (*context));
 178 }
 179
 180 /* MD4 basic transformation. Transforms state based on block.
 181  */
 182 static void
 183 __kern__MD4Transform(UINT4 state[4], const unsigned char block[64])
 184 {
 185   UINT4 a = state[0], b = state[1], c = state[2], d = state[3], x[16];
 186
 187   Decode (x, block, 64);
 188
 189   /* Round 1 */
 190   FF (a, b, c, d, x[ 0], S11); /* 1 */
 191   FF (d, a, b, c, x[ 1], S12); /* 2 */
 192   FF (c, d, a, b, x[ 2], S13); /* 3 */
 193   FF (b, c, d, a, x[ 3], S14); /* 4 */
 194   FF (a, b, c, d, x[ 4], S11); /* 5 */
 195   FF (d, a, b, c, x[ 5], S12); /* 6 */
 196   FF (c, d, a, b, x[ 6], S13); /* 7 */
 197   FF (b, c, d, a, x[ 7], S14); /* 8 */
 198   FF (a, b, c, d, x[ 8], S11); /* 9 */
 199   FF (d, a, b, c, x[ 9], S12); /* 10 */
 200   FF (c, d, a, b, x[10], S13); /* 11 */
 201   FF (b, c, d, a, x[11], S14); /* 12 */
 202   FF (a, b, c, d, x[12], S11); /* 13 */
 203   FF (d, a, b, c, x[13], S12); /* 14 */
 204   FF (c, d, a, b, x[14], S13); /* 15 */
 205   FF (b, c, d, a, x[15], S14); /* 16 */
 206
 207   /* Round 2 */
 208   GG (a, b, c, d, x[ 0], S21); /* 17 */
 209   GG (d, a, b, c, x[ 4], S22); /* 18 */
 210   GG (c, d, a, b, x[ 8], S23); /* 19 */
 211   GG (b, c, d, a, x[12], S24); /* 20 */
 212   GG (a, b, c, d, x[ 1], S21); /* 21 */
 213   GG (d, a, b, c, x[ 5], S22); /* 22 */
 214   GG (c, d, a, b, x[ 9], S23); /* 23 */
 215   GG (b, c, d, a, x[13], S24); /* 24 */
 216   GG (a, b, c, d, x[ 2], S21); /* 25 */
 217   GG (d, a, b, c, x[ 6], S22); /* 26 */
 218   GG (c, d, a, b, x[10], S23); /* 27 */
 219   GG (b, c, d, a, x[14], S24); /* 28 */
 220   GG (a, b, c, d, x[ 3], S21); /* 29 */
 221   GG (d, a, b, c, x[ 7], S22); /* 30 */
 222   GG (c, d, a, b, x[11], S23); /* 31 */
 223   GG (b, c, d, a, x[15], S24); /* 32 */
 224
 225   /* Round 3 */
 226   HH (a, b, c, d, x[ 0], S31); /* 33 */
 227   HH (d, a, b, c, x[ 8], S32); /* 34 */
 228   HH (c, d, a, b, x[ 4], S33); /* 35 */
 229   HH (b, c, d, a, x[12], S34); /* 36 */
 230   HH (a, b, c, d, x[ 2], S31); /* 37 */
 231   HH (d, a, b, c, x[10], S32); /* 38 */
 232   HH (c, d, a, b, x[ 6], S33); /* 39 */
 233   HH (b, c, d, a, x[14], S34); /* 40 */
 234   HH (a, b, c, d, x[ 1], S31); /* 41 */
 235   HH (d, a, b, c, x[ 9], S32); /* 42 */
 236   HH (c, d, a, b, x[ 5], S33); /* 43 */
 237   HH (b, c, d, a, x[13], S34); /* 44 */
 238   HH (a, b, c, d, x[ 3], S31); /* 45 */
 239   HH (d, a, b, c, x[11], S32); /* 46 */
 240   HH (c, d, a, b, x[ 7], S33); /* 47 */
 241   HH (b, c, d, a, x[15], S34); /* 48 */
 242
 243   state[0] += a;
 244   state[1] += b;
 245   state[2] += c;
 246   state[3] += d;
 247
 248   /* Zeroize sensitive information.
 249    */
 250   bzero((POINTER)x, sizeof (x));
 251 }
 252
 253 /* Encodes input (UINT4) into output (unsigned char). Assumes len is
 254      a multiple of 4.
 255  */
 256 static void
 257 Encode(unsigned char *output, UINT4 *input, unsigned int len)
 258 {
 259   unsigned int i, j;
 260
 261   for (i = 0, j = 0; j < len; i++, j += 4) {
 262     output[j] = (unsigned char)(input[i] & 0xff);
 263     output[j+1] = (unsigned char)((input[i] >> 8) & 0xff);
 264     output[j+2] = (unsigned char)((input[i] >> 16) & 0xff);
 265     output[j+3] = (unsigned char)((input[i] >> 24) & 0xff);
 266   }
 267 }
 268
 269 /* Decodes input (unsigned char) into output (UINT4). Assumes len is
 270      a multiple of 4.
 271  */
 272 static void
 273 Decode(UINT4 *output, const unsigned char *input, unsigned int len)
 274 {
 275   unsigned int i, j;
 276
 277   for (i = 0, j = 0; j < len; i++, j += 4)
 278     output[i] = ((UINT4)input[j]) | (((UINT4)input[j+1]) << 8) |
 279       (((UINT4)input[j+2]) << 16) | (((UINT4)input[j+3]) << 24);
 280 }