md5.c

   1 /*
   2  ***********************************************************************
   3  ** md5.c -- the source code for MD5 routines                         **
   4  ** RSA Data Security, Inc. MD5 Message-Digest Algorithm              **
   5  ** Created: 2/17/90 RLR                                              **
   6  ** Revised: 1/91 SRD,AJ,BSK,JT Reference C Version                   **
   7  ** Revised (for MD5): RLR 4/27/91                                    **
   8  **   -- G modified to have y&~z instead of y&z                       **
   9  **   -- FF, GG, HH modified to add in last register done             **
  10  **   -- Access pattern: round 2 works mod 5, round 3 works mod 3     **
  11  **   -- distinct additive constant for each step                     **
  12  **   -- round 4 added, working mod 7                                 **
  13  ***********************************************************************
  14  */
  15
  16 /*
  17  ***********************************************************************
  18  ** Copyright (C) 1990, RSA Data Security, Inc. All rights reserved.  **
  19  **                                                                   **
  20  ** License to copy and use this software is granted provided that    **
  21  ** it is identified as the "RSA Data Security, Inc. MD5 Message-     **
  22  ** Digest Algorithm" in all material mentioning or referencing this  **
  23  ** software or this function.                                        **
  24  **                                                                   **
  25  ** License is also granted to make and use derivative works          **
  26  ** provided that such works are identified as "derived from the RSA  **
  27  ** Data Security, Inc. MD5 Message-Digest Algorithm" in all          **
  28  ** material mentioning or referencing the derived work.              **
  29  **                                                                   **
  30  ** RSA Data Security, Inc. makes no representations concerning       **
  31  ** either the merchantability of this software or the suitability    **
  32  ** of this software for any particular purpose.  It is provided "as  **
  33  ** is" without express or implied warranty of any kind.              **
  34  **                                                                   **
  35  ** These notices must be retained in any copies of any part of this  **
  36  ** documentation and/or software.                                    **
  37  ***********************************************************************
  38  */
  39
  40 #include "md5.h"
  41
  42 /*
  43  ***********************************************************************
  44  **  Message-digest routines:                                         **
  45  **  To form the message digest for a message M                       **
  46  **    (1) Initialize a context buffer mdContext using MD5Init        **
  47  **    (2) Call MD5Update on mdContext and M                          **
  48  **    (3) Call MD5Final on mdContext                                 **
  49  **  The message digest is now in mdContext->digest[0...15]           **
  50  ***********************************************************************
  51  */
  52
  53 /* forward declaration */
  54 static void Transform (UINT4 *, UINT4 *);
  55
  56 #ifdef  __STDC__
  57 static const
  58 #else
  59 static
  60 #endif
  61 unsigned char PADDING[64] = {
  62   0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  63   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  64   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  65   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  66   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  67   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  68   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  69   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
  70 };
  71
  72 /* F, G, H and I are basic MD5 functions */
  73 #define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
  74 #define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
  75 #define H(x, y, z) ((x) ^ (y) ^ (z))
  76 #define I(x, y, z) ((y) ^ ((x) | (~z)))
  77
  78 /* ROTATE_LEFT rotates x left n bits */
  79 #if     defined(FAST_MD5) && defined(__GNUC__) && defined(mc68000)
  80 /*
  81  * If we're on a 68000 based CPU and using a GNU C compiler with
  82  * inline assembly code, we can speed this up a bit.
  83  */
  84 inline UINT4 ROTATE_LEFT(UINT4 x, int n)
  85 {
  86     asm("roll %2,%0" : "=d" (x) : "0" (x), "Ir" (n));
  87     return x;
  88 }
  89 #else
  90 #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
  91 #endif
  92
  93
  94 /* FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4 */
  95 /* Rotation is separate from addition to prevent recomputation */
  96 #define FF(a, b, c, d, x, s, ac) \
  97   {(a) += F ((b), (c), (d)) + (x) + (UINT4)(ac); \
  98    (a) = ROTATE_LEFT ((a), (s)); \
  99    (a) += (b); \
 100   }
 101 #define GG(a, b, c, d, x, s, ac) \
 102   {(a) += G ((b), (c), (d)) + (x) + (UINT4)(ac); \
 103    (a) = ROTATE_LEFT ((a), (s)); \
 104    (a) += (b); \
 105   }
 106 #define HH(a, b, c, d, x, s, ac) \
 107   {(a) += H ((b), (c), (d)) + (x) + (UINT4)(ac); \
 108    (a) = ROTATE_LEFT ((a), (s)); \
 109    (a) += (b); \
 110   }
 111 #define II(a, b, c, d, x, s, ac) \
 112   {(a) += I ((b), (c), (d)) + (x) + (UINT4)(ac); \
 113    (a) = ROTATE_LEFT ((a), (s)); \
 114    (a) += (b); \
 115   }
 116
 117 /* The routine MD5Init initializes the message-digest context
 118    mdContext. All fields are set to zero.
 119  */
 120 void MD5Init (mdContext)
 121 MD5_CTX *mdContext;
 122 {
 123   mdContext->i[0] = mdContext->i[1] = (UINT4)0;
 124
 125   /* Load magic initialization constants.
 126    */
 127   mdContext->buf[0] = (UINT4)0x67452301;
 128   mdContext->buf[1] = (UINT4)0xefcdab89;
 129   mdContext->buf[2] = (UINT4)0x98badcfe;
 130   mdContext->buf[3] = (UINT4)0x10325476;
 131 }
 132
 133 /* The routine MD5Update updates the message-digest context to
 134    account for the presence of each of the characters inBuf[0..inLen-1]
 135    in the message whose digest is being computed.
 136  */
 137 void MD5Update (mdContext, inBuf, inLen)
 138 MD5_CTX *mdContext;
 139 unsigned const char *inBuf;
 140 unsigned int inLen;
 141 {
 142   UINT4 in[16];
 143   int mdi;
 144   unsigned int i, ii;
 145
 146   /* compute number of bytes mod 64 */
 147   mdi = (int)((mdContext->i[0] >> 3) & 0x3F);
 148
 149   /* update number of bits */
 150   if ((mdContext->i[0] + ((UINT4)inLen << 3)) < mdContext->i[0])
 151     mdContext->i[1]++;
 152   mdContext->i[0] += ((UINT4)inLen << 3);
 153   mdContext->i[1] += ((UINT4)inLen >> 29);
 154
 155   while (inLen--) {
 156     /* add new character to buffer, increment mdi */
 157     mdContext->in[mdi++] = *inBuf++;
 158
 159     /* transform if necessary */
 160     if (mdi == 0x40) {
 161       for (i = 0, ii = 0; i < 16; i++, ii += 4)
 162         in[i] = (((UINT4)mdContext->in[ii+3]) << 24) |
 163                 (((UINT4)mdContext->in[ii+2]) << 16) |
 164                 (((UINT4)mdContext->in[ii+1]) << 8) |
 165                 ((UINT4)mdContext->in[ii]);
 166       Transform (mdContext->buf, in);
 167       mdi = 0;
 168     }
 169   }
 170 }
 171
 172 /* The routine MD5Final terminates the message-digest computation and
 173    ends with the desired message digest in mdContext->digest[0...15].
 174  */
 175
 176 void MD5Final (mdContext)
 177 MD5_CTX *mdContext;
 178 {
 179   UINT4 in[16];
 180   int mdi;
 181   unsigned int i, ii;
 182   unsigned int padLen;
 183
 184   /* save number of bits */
 185   in[14] = mdContext->i[0];
 186   in[15] = mdContext->i[1];
 187
 188   /* compute number of bytes mod 64 */
 189   mdi = (int)((mdContext->i[0] >> 3) & 0x3F);
 190
 191   /* pad out to 56 mod 64 */
 192   padLen = (mdi < 56) ? (56 - mdi) : (120 - mdi);
 193   MD5Update (mdContext, PADDING, padLen);
 194
 195   /* append length in bits and transform */
 196   for (i = 0, ii = 0; i < 14; i++, ii += 4)
 197     in[i] = (((UINT4)mdContext->in[ii+3]) << 24) |
 198             (((UINT4)mdContext->in[ii+2]) << 16) |
 199             (((UINT4)mdContext->in[ii+1]) << 8) |
 200             ((UINT4)mdContext->in[ii]);
 201   Transform (mdContext->buf, in);
 202
 203   /* store buffer in digest */
 204   for (i = 0, ii = 0; i < 4; i++, ii += 4) {
 205     mdContext->digest[ii] = (unsigned char)(mdContext->buf[i] & 0xFF);
 206     mdContext->digest[ii+1] =
 207       (unsigned char)((mdContext->buf[i] >> 8) & 0xFF);
 208     mdContext->digest[ii+2] =
 209       (unsigned char)((mdContext->buf[i] >> 16) & 0xFF);
 210     mdContext->digest[ii+3] =
 211       (unsigned char)((mdContext->buf[i] >> 24) & 0xFF);
 212   }
 213 }
 214
 215 /* Basic MD5 step. Transforms buf based on in.
 216  */
 217 static void Transform (buf, in)
 218 UINT4 *buf;
 219 UINT4 *in;
 220 {
 221   UINT4 a = buf[0], b = buf[1], c = buf[2], d = buf[3];
 222
 223   /* Round 1 */
 224 #define S11 7
 225 #define S12 12
 226 #define S13 17
 227 #define S14 22
 228
 229   FF ( a, b, c, d, in[ 0], S11, 0xd76aa478); /* 1 */
 230   FF ( d, a, b, c, in[ 1], S12, 0xe8c7b756); /* 2 */
 231   FF ( c, d, a, b, in[ 2], S13, 0x242070db); /* 3 */
 232   FF ( b, c, d, a, in[ 3], S14, 0xc1bdceee); /* 4 */
 233   FF ( a, b, c, d, in[ 4], S11, 0xf57c0faf); /* 5 */
 234   FF ( d, a, b, c, in[ 5], S12, 0x4787c62a); /* 6 */
 235   FF ( c, d, a, b, in[ 6], S13, 0xa8304613); /* 7 */
 236   FF ( b, c, d, a, in[ 7], S14, 0xfd469501); /* 8 */
 237   FF ( a, b, c, d, in[ 8], S11, 0x698098d8); /* 9 */
 238   FF ( d, a, b, c, in[ 9], S12, 0x8b44f7af); /* 10 */
 239   FF ( c, d, a, b, in[10], S13, 0xffff5bb1); /* 11 */
 240   FF ( b, c, d, a, in[11], S14, 0x895cd7be); /* 12 */
 241   FF ( a, b, c, d, in[12], S11, 0x6b901122); /* 13 */
 242   FF ( d, a, b, c, in[13], S12, 0xfd987193); /* 14 */
 243   FF ( c, d, a, b, in[14], S13, 0xa679438e); /* 15 */
 244   FF ( b, c, d, a, in[15], S14, 0x49b40821); /* 16 */
 245
 246   /* Round 2 */
 247 #define S21 5
 248 #define S22 9
 249 #define S23 14
 250 #define S24 20
 251   GG ( a, b, c, d, in[ 1], S21, 0xf61e2562); /* 17 */
 252   GG ( d, a, b, c, in[ 6], S22, 0xc040b340); /* 18 */
 253   GG ( c, d, a, b, in[11], S23, 0x265e5a51); /* 19 */
 254   GG ( b, c, d, a, in[ 0], S24, 0xe9b6c7aa); /* 20 */
 255   GG ( a, b, c, d, in[ 5], S21, 0xd62f105d); /* 21 */
 256   GG ( d, a, b, c, in[10], S22,  0x2441453); /* 22 */
 257   GG ( c, d, a, b, in[15], S23, 0xd8a1e681); /* 23 */
 258   GG ( b, c, d, a, in[ 4], S24, 0xe7d3fbc8); /* 24 */
 259   GG ( a, b, c, d, in[ 9], S21, 0x21e1cde6); /* 25 */
 260   GG ( d, a, b, c, in[14], S22, 0xc33707d6); /* 26 */
 261   GG ( c, d, a, b, in[ 3], S23, 0xf4d50d87); /* 27 */
 262   GG ( b, c, d, a, in[ 8], S24, 0x455a14ed); /* 28 */
 263   GG ( a, b, c, d, in[13], S21, 0xa9e3e905); /* 29 */
 264   GG ( d, a, b, c, in[ 2], S22, 0xfcefa3f8); /* 30 */
 265   GG ( c, d, a, b, in[ 7], S23, 0x676f02d9); /* 31 */
 266   GG ( b, c, d, a, in[12], S24, 0x8d2a4c8a); /* 32 */
 267
 268   /* Round 3 */
 269 #define S31 4
 270 #define S32 11
 271 #define S33 16
 272 #define S34 23
 273   HH ( a, b, c, d, in[ 5], S31, 0xfffa3942); /* 33 */
 274   HH ( d, a, b, c, in[ 8], S32, 0x8771f681); /* 34 */
 275   HH ( c, d, a, b, in[11], S33, 0x6d9d6122); /* 35 */
 276   HH ( b, c, d, a, in[14], S34, 0xfde5380c); /* 36 */
 277   HH ( a, b, c, d, in[ 1], S31, 0xa4beea44); /* 37 */
 278   HH ( d, a, b, c, in[ 4], S32, 0x4bdecfa9); /* 38 */
 279   HH ( c, d, a, b, in[ 7], S33, 0xf6bb4b60); /* 39 */
 280   HH ( b, c, d, a, in[10], S34, 0xbebfbc70); /* 40 */
 281   HH ( a, b, c, d, in[13], S31, 0x289b7ec6); /* 41 */
 282   HH ( d, a, b, c, in[ 0], S32, 0xeaa127fa); /* 42 */
 283   HH ( c, d, a, b, in[ 3], S33, 0xd4ef3085); /* 43 */
 284   HH ( b, c, d, a, in[ 6], S34,  0x4881d05); /* 44 */
 285   HH ( a, b, c, d, in[ 9], S31, 0xd9d4d039); /* 45 */
 286   HH ( d, a, b, c, in[12], S32, 0xe6db99e5); /* 46 */
 287   HH ( c, d, a, b, in[15], S33, 0x1fa27cf8); /* 47 */
 288   HH ( b, c, d, a, in[ 2], S34, 0xc4ac5665); /* 48 */
 289
 290   /* Round 4 */
 291 #define S41 6
 292 #define S42 10
 293 #define S43 15
 294 #define S44 21
 295   II ( a, b, c, d, in[ 0], S41, 0xf4292244); /* 49 */
 296   II ( d, a, b, c, in[ 7], S42, 0x432aff97); /* 50 */
 297   II ( c, d, a, b, in[14], S43, 0xab9423a7); /* 51 */
 298   II ( b, c, d, a, in[ 5], S44, 0xfc93a039); /* 52 */
 299   II ( a, b, c, d, in[12], S41, 0x655b59c3); /* 53 */
 300   II ( d, a, b, c, in[ 3], S42, 0x8f0ccc92); /* 54 */
 301   II ( c, d, a, b, in[10], S43, 0xffeff47d); /* 55 */
 302   II ( b, c, d, a, in[ 1], S44, 0x85845dd1); /* 56 */
 303   II ( a, b, c, d, in[ 8], S41, 0x6fa87e4f); /* 57 */
 304   II ( d, a, b, c, in[15], S42, 0xfe2ce6e0); /* 58 */
 305   II ( c, d, a, b, in[ 6], S43, 0xa3014314); /* 59 */
 306   II ( b, c, d, a, in[13], S44, 0x4e0811a1); /* 60 */
 307   II ( a, b, c, d, in[ 4], S41, 0xf7537e82); /* 61 */
 308   II ( d, a, b, c, in[11], S42, 0xbd3af235); /* 62 */
 309   II ( c, d, a, b, in[ 2], S43, 0x2ad7d2bb); /* 63 */
 310   II ( b, c, d, a, in[ 9], S44, 0xeb86d391); /* 64 */
 311
 312   buf[0] += a;
 313   buf[1] += b;
 314   buf[2] += c;
 315   buf[3] += d;
 316 }
 317
 318 /*
 319  ***********************************************************************
 320  ** End of md5.c                                                      **
 321  ******************************** (cut) ********************************
 322  */