Modules/md5c.c

   1 /* MD5C.C - RSA Data Security, Inc., MD5 message-digest algorithm
   2  */
   3
   4 /* Copyright (C) 1991-2, RSA Data Security, Inc. Created 1991. All
   5 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. MD5 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. MD5 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 #ifdef HAVE_CONFIG_H
  27 #include "config.h"
  28 #endif
  29 #include "md5.h"
  30
  31 /* Constants for MD5Transform routine.
  32  */
  33
  34 #define S11 7
  35 #define S12 12
  36 #define S13 17
  37 #define S14 22
  38 #define S21 5
  39 #define S22 9
  40 #define S23 14
  41 #define S24 20
  42 #define S31 4
  43 #define S32 11
  44 #define S33 16
  45 #define S34 23
  46 #define S41 6
  47 #define S42 10
  48 #define S43 15
  49 #define S44 21
  50
  51 static void MD5Transform PROTO_LIST ((UINT4 [4], unsigned char [64]));
  52 static void Encode PROTO_LIST
  53   ((unsigned char *, UINT4 *, unsigned int));
  54 static void Decode PROTO_LIST
  55   ((UINT4 *, unsigned char *, unsigned int));
  56 static void MD5_memcpy PROTO_LIST ((POINTER, POINTER, unsigned int));
  57 static void MD5_memset PROTO_LIST ((POINTER, int, 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, H and I are basic MD5 functions.
  66  */
  67 #define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
  68 #define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
  69 #define H(x, y, z) ((x) ^ (y) ^ (z))
  70 #define I(x, y, z) ((y) ^ ((x) | (~z)))
  71
  72 /* ROTATE_LEFT rotates x left n bits.
  73  */
  74 #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
  75
  76 /* FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4.
  77 Rotation is separate from addition to prevent recomputation.
  78  */
  79 #define FF(a, b, c, d, x, s, ac) { \
  80  (a) += F ((b), (c), (d)) + (x) + (UINT4)(ac); \
  81  (a) = ROTATE_LEFT ((a), (s)); \
  82  (a) += (b); \
  83   }
  84 #define GG(a, b, c, d, x, s, ac) { \
  85  (a) += G ((b), (c), (d)) + (x) + (UINT4)(ac); \
  86  (a) = ROTATE_LEFT ((a), (s)); \
  87  (a) += (b); \
  88   }
  89 #define HH(a, b, c, d, x, s, ac) { \
  90  (a) += H ((b), (c), (d)) + (x) + (UINT4)(ac); \
  91  (a) = ROTATE_LEFT ((a), (s)); \
  92  (a) += (b); \
  93   }
  94 #define II(a, b, c, d, x, s, ac) { \
  95  (a) += I ((b), (c), (d)) + (x) + (UINT4)(ac); \
  96  (a) = ROTATE_LEFT ((a), (s)); \
  97  (a) += (b); \
  98   }
  99
 100 /* MD5 initialization. Begins an MD5 operation, writing a new context.
 101  */
 102 void MD5Init (context)
 103 MD5_CTX *context;                                        /* context */
 104 {
 105   context->count[0] = context->count[1] = 0;
 106   /* Load magic initialization constants.
 107 */
 108   context->state[0] = 0x67452301;
 109   context->state[1] = 0xefcdab89;
 110   context->state[2] = 0x98badcfe;
 111   context->state[3] = 0x10325476;
 112 }
 113
 114 /* MD5 block update operation. Continues an MD5 message-digest
 115   operation, processing another message block, and updating the
 116   context.
 117  */
 118 void MD5Update (context, input, inputLen)
 119 MD5_CTX *context;                                        /* context */
 120 unsigned char *input;                                /* input block */
 121 unsigned int inputLen;                     /* length of input block */
 122 {
 123   unsigned int i, index, partLen;
 124
 125   /* Compute number of bytes mod 64 */
 126   index = (unsigned int)((context->count[0] >> 3) & 0x3F);
 127
 128   /* Update number of bits */
 129   if ((context->count[0] += ((UINT4)inputLen << 3))
 130    < ((UINT4)inputLen << 3))
 131  context->count[1]++;
 132   context->count[1] += ((UINT4)inputLen >> 29);
 133
 134   partLen = 64 - index;
 135
 136   /* Transform as many times as possible.
 137 */
 138   if (inputLen >= partLen) {
 139  MD5_memcpy
 140    ((POINTER)&context->buffer[index], (POINTER)input, partLen);
 141  MD5Transform (context->state, context->buffer);
 142
 143  for (i = partLen; i + 63 < inputLen; i += 64)
 144    MD5Transform (context->state, &input[i]);
 145
 146  index = 0;
 147   }
 148   else
 149  i = 0;
 150
 151   /* Buffer remaining input */
 152   MD5_memcpy
 153  ((POINTER)&context->buffer[index], (POINTER)&input[i],
 154   inputLen-i);
 155 }
 156
 157 /* MD5 finalization. Ends an MD5 message-digest operation, writing the
 158   the message digest and zeroizing the context.
 159  */
 160 void MD5Final (digest, context)
 161 unsigned char digest[16];                         /* message digest */
 162 MD5_CTX *context;                                       /* context */
 163 {
 164   unsigned char bits[8];
 165   unsigned int index, padLen;
 166
 167   /* Save number of bits */
 168   Encode (bits, context->count, 8);
 169
 170   /* Pad out to 56 mod 64.
 171 */
 172   index = (unsigned int)((context->count[0] >> 3) & 0x3f);
 173   padLen = (index < 56) ? (56 - index) : (120 - index);
 174   MD5Update (context, PADDING, padLen);
 175
 176   /* Append length (before padding) */
 177   MD5Update (context, bits, 8);
 178
 179   /* Store state in digest */
 180   Encode (digest, context->state, 16);
 181
 182   /* Zeroize sensitive information.
 183 */
 184   MD5_memset ((POINTER)context, 0, sizeof (*context));
 185 }
 186
 187 /* MD5 basic transformation. Transforms state based on block.
 188  */
 189 static void MD5Transform (state, block)
 190 UINT4 state[4];
 191 unsigned char block[64];
 192 {
 193   UINT4 a = state[0], b = state[1], c = state[2], d = state[3], x[16];
 194
 195   Decode (x, block, 64);
 196
 197   /* Round 1 */
 198   FF (a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1 */
 199   FF (d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2 */
 200   FF (c, d, a, b, x[ 2], S13, 0x242070db); /* 3 */
 201   FF (b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4 */
 202   FF (a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5 */
 203   FF (d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6 */
 204   FF (c, d, a, b, x[ 6], S13, 0xa8304613); /* 7 */
 205   FF (b, c, d, a, x[ 7], S14, 0xfd469501); /* 8 */
 206   FF (a, b, c, d, x[ 8], S11, 0x698098d8); /* 9 */
 207   FF (d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10 */
 208   FF (c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */
 209   FF (b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */
 210   FF (a, b, c, d, x[12], S11, 0x6b901122); /* 13 */
 211   FF (d, a, b, c, x[13], S12, 0xfd987193); /* 14 */
 212   FF (c, d, a, b, x[14], S13, 0xa679438e); /* 15 */
 213   FF (b, c, d, a, x[15], S14, 0x49b40821); /* 16 */
 214
 215  /* Round 2 */
 216   GG (a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17 */
 217   GG (d, a, b, c, x[ 6], S22, 0xc040b340); /* 18 */
 218   GG (c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */
 219   GG (b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20 */
 220   GG (a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21 */
 221   GG (d, a, b, c, x[10], S22,  0x2441453); /* 22 */
 222   GG (c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */
 223   GG (b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24 */
 224   GG (a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25 */
 225   GG (d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */
 226   GG (c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27 */
 227   GG (b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28 */
 228   GG (a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */
 229   GG (d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30 */
 230   GG (c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31 */
 231   GG (b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */
 232
 233   /* Round 3 */
 234   HH (a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33 */
 235   HH (d, a, b, c, x[ 8], S32, 0x8771f681); /* 34 */
 236   HH (c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */
 237   HH (b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */
 238   HH (a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37 */
 239   HH (d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38 */
 240   HH (c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39 */
 241   HH (b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */
 242   HH (a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */
 243   HH (d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42 */
 244   HH (c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43 */
 245   HH (b, c, d, a, x[ 6], S34,  0x4881d05); /* 44 */
 246   HH (a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45 */
 247   HH (d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */
 248   HH (c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */
 249   HH (b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48 */
 250
 251   /* Round 4 */
 252   II (a, b, c, d, x[ 0], S41, 0xf4292244); /* 49 */
 253   II (d, a, b, c, x[ 7], S42, 0x432aff97); /* 50 */
 254   II (c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */
 255   II (b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52 */
 256   II (a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */
 257   II (d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54 */
 258   II (c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */
 259   II (b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56 */
 260   II (a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57 */
 261   II (d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */
 262   II (c, d, a, b, x[ 6], S43, 0xa3014314); /* 59 */
 263   II (b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */
 264   II (a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61 */
 265   II (d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */
 266   II (c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63 */
 267   II (b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64 */
 268
 269   state[0] += a;
 270   state[1] += b;
 271   state[2] += c;
 272   state[3] += d;
 273
 274   /* Zeroize sensitive information.
 275 */
 276   MD5_memset ((POINTER)x, 0, sizeof (x));
 277 }
 278
 279 /* Encodes input (UINT4) into output (unsigned char). Assumes len is
 280   a multiple of 4.
 281  */
 282 static void Encode (output, input, len)
 283 unsigned char *output;
 284 UINT4 *input;
 285 unsigned int len;
 286 {
 287   unsigned int i, j;
 288
 289   for (i = 0, j = 0; j < len; i++, j += 4) {
 290  output[j] = (unsigned char)(input[i] & 0xff);
 291  output[j+1] = (unsigned char)((input[i] >> 8) & 0xff);
 292  output[j+2] = (unsigned char)((input[i] >> 16) & 0xff);
 293  output[j+3] = (unsigned char)((input[i] >> 24) & 0xff);
 294   }
 295 }
 296
 297 /* Decodes input (unsigned char) into output (UINT4). Assumes len is
 298   a multiple of 4.
 299  */
 300 static void Decode (output, input, len)
 301 UINT4 *output;
 302 unsigned char *input;
 303 unsigned int len;
 304 {
 305   unsigned int i, j;
 306
 307   for (i = 0, j = 0; j < len; i++, j += 4)
 308  output[i] = ((UINT4)input[j]) | (((UINT4)input[j+1]) << 8) |
 309    (((UINT4)input[j+2]) << 16) | (((UINT4)input[j+3]) << 24);
 310 }
 311
 312 /* Note: Replace "for loop" with standard memcpy if possible.
 313  */
 314
 315 static void MD5_memcpy (output, input, len)
 316 POINTER output;
 317 POINTER input;
 318 unsigned int len;
 319 {
 320   unsigned int i;
 321
 322   for (i = 0; i < len; i++)
 323  output[i] = input[i];
 324 }
 325
 326 /* Note: Replace "for loop" with standard memset if possible.
 327  */
 328 static void MD5_memset (output, value, len)
 329 POINTER output;
 330 int value;
 331 unsigned int len;
 332 {
 333   unsigned int i;
 334
 335   for (i = 0; i < len; i++)
 336  ((char *)output)[i] = (char)value;
 337 }