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 #include "md5.h"
  27
  28 /* Constants for MD5Transform routine.
  29  */
  30
  31 #define S11 7
  32 #define S12 12
  33 #define S13 17
  34 #define S14 22
  35 #define S21 5
  36 #define S22 9
  37 #define S23 14
  38 #define S24 20
  39 #define S31 4
  40 #define S32 11
  41 #define S33 16
  42 #define S34 23
  43 #define S41 6
  44 #define S42 10
  45 #define S43 15
  46 #define S44 21
  47
  48 static void MD5Transform PROTO_LIST ((UINT4 [4], unsigned char [64]));
  49 static void Encode PROTO_LIST
  50   ((unsigned char *, UINT4 *, unsigned int));
  51 static void Decode PROTO_LIST
  52   ((UINT4 *, unsigned char *, unsigned int));
  53 static void MD5_memcpy PROTO_LIST ((POINTER, POINTER, unsigned int));
  54 static void MD5_memset PROTO_LIST ((POINTER, int, unsigned int));
  55
  56 static unsigned char PADDING[64] = {
  57   0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  58   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  59   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
  60 };
  61
  62 /* F, G, H and I are basic MD5 functions.
  63  */
  64 #define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
  65 #define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
  66 #define H(x, y, z) ((x) ^ (y) ^ (z))
  67 #define I(x, y, z) ((y) ^ ((x) | (~z)))
  68
  69 /* ROTATE_LEFT rotates x left n bits.
  70  */
  71 #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
  72
  73 /* FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4.
  74 Rotation is separate from addition to prevent recomputation.
  75  */
  76 #define FF(a, b, c, d, x, s, ac) { \
  77  (a) += F ((b), (c), (d)) + (x) + (UINT4)(ac); \
  78  (a) = ROTATE_LEFT ((a), (s)); \
  79  (a) += (b); \
  80   }
  81 #define GG(a, b, c, d, x, s, ac) { \
  82  (a) += G ((b), (c), (d)) + (x) + (UINT4)(ac); \
  83  (a) = ROTATE_LEFT ((a), (s)); \
  84  (a) += (b); \
  85   }
  86 #define HH(a, b, c, d, x, s, ac) { \
  87  (a) += H ((b), (c), (d)) + (x) + (UINT4)(ac); \
  88  (a) = ROTATE_LEFT ((a), (s)); \
  89  (a) += (b); \
  90   }
  91 #define II(a, b, c, d, x, s, ac) { \
  92  (a) += I ((b), (c), (d)) + (x) + (UINT4)(ac); \
  93  (a) = ROTATE_LEFT ((a), (s)); \
  94  (a) += (b); \
  95   }
  96
  97 /* MD5 initialization. Begins an MD5 operation, writing a new context.
  98  */
  99 void MD5Init (context)
 100 MD5_CTX *context;                                        /* context */
 101 {
 102   context->count[0] = context->count[1] = 0;
 103   /* Load magic initialization constants.
 104 */
 105   context->state[0] = 0x67452301;
 106   context->state[1] = 0xefcdab89;
 107   context->state[2] = 0x98badcfe;
 108   context->state[3] = 0x10325476;
 109 }
 110
 111 /* MD5 block update operation. Continues an MD5 message-digest
 112   operation, processing another message block, and updating the
 113   context.
 114  */
 115 void MD5Update (context, input, inputLen)
 116 MD5_CTX *context;                                        /* context */
 117 unsigned char *input;                                /* input block */
 118 unsigned int inputLen;                     /* length of input block */
 119 {
 120   unsigned int i, index, partLen;
 121
 122   /* Compute number of bytes mod 64 */
 123   index = (unsigned int)((context->count[0] >> 3) & 0x3F);
 124
 125   /* Update number of bits */
 126   if ((context->count[0] += ((UINT4)inputLen << 3))
 127    < ((UINT4)inputLen << 3))
 128  context->count[1]++;
 129   context->count[1] += ((UINT4)inputLen >> 29);
 130
 131   partLen = 64 - index;
 132
 133   /* Transform as many times as possible.
 134 */
 135   if (inputLen >= partLen) {
 136  MD5_memcpy
 137    ((POINTER)&context->buffer[index], (POINTER)input, partLen);
 138  MD5Transform (context->state, context->buffer);
 139
 140  for (i = partLen; i + 63 < inputLen; i += 64)
 141    MD5Transform (context->state, &input[i]);
 142
 143  index = 0;
 144   }
 145   else
 146  i = 0;
 147
 148   /* Buffer remaining input */
 149   MD5_memcpy
 150  ((POINTER)&context->buffer[index], (POINTER)&input[i],
 151   inputLen-i);
 152 }
 153
 154 /* MD5 finalization. Ends an MD5 message-digest operation, writing the
 155   the message digest and zeroizing the context.
 156  */
 157 void MD5Final (digest, context)
 158 unsigned char digest[16];                         /* message digest */
 159 MD5_CTX *context;                                       /* context */
 160 {
 161   unsigned char bits[8];
 162   unsigned int index, padLen;
 163
 164   /* Save number of bits */
 165   Encode (bits, context->count, 8);
 166
 167   /* Pad out to 56 mod 64.
 168 */
 169   index = (unsigned int)((context->count[0] >> 3) & 0x3f);
 170   padLen = (index < 56) ? (56 - index) : (120 - index);
 171   MD5Update (context, PADDING, padLen);
 172
 173   /* Append length (before padding) */
 174   MD5Update (context, bits, 8);
 175
 176   /* Store state in digest */
 177   Encode (digest, context->state, 16);
 178
 179   /* Zeroize sensitive information.
 180 */
 181   MD5_memset ((POINTER)context, 0, sizeof (*context));
 182 }
 183
 184 /* MD5 basic transformation. Transforms state based on block.
 185  */
 186 static void MD5Transform (state, block)
 187 UINT4 state[4];
 188 unsigned char block[64];
 189 {
 190   UINT4 a = state[0], b = state[1], c = state[2], d = state[3], x[16];
 191
 192   Decode (x, block, 64);
 193
 194   /* Round 1 */
 195   FF (a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1 */
 196   FF (d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2 */
 197   FF (c, d, a, b, x[ 2], S13, 0x242070db); /* 3 */
 198   FF (b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4 */
 199   FF (a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5 */
 200   FF (d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6 */
 201   FF (c, d, a, b, x[ 6], S13, 0xa8304613); /* 7 */
 202   FF (b, c, d, a, x[ 7], S14, 0xfd469501); /* 8 */
 203   FF (a, b, c, d, x[ 8], S11, 0x698098d8); /* 9 */
 204   FF (d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10 */
 205   FF (c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */
 206   FF (b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */
 207   FF (a, b, c, d, x[12], S11, 0x6b901122); /* 13 */
 208   FF (d, a, b, c, x[13], S12, 0xfd987193); /* 14 */
 209   FF (c, d, a, b, x[14], S13, 0xa679438e); /* 15 */
 210   FF (b, c, d, a, x[15], S14, 0x49b40821); /* 16 */
 211
 212  /* Round 2 */
 213   GG (a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17 */
 214   GG (d, a, b, c, x[ 6], S22, 0xc040b340); /* 18 */
 215   GG (c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */
 216   GG (b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20 */
 217   GG (a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21 */
 218   GG (d, a, b, c, x[10], S22,  0x2441453); /* 22 */
 219   GG (c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */
 220   GG (b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24 */
 221   GG (a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25 */
 222   GG (d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */
 223   GG (c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27 */
 224   GG (b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28 */
 225   GG (a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */
 226   GG (d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30 */
 227   GG (c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31 */
 228   GG (b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */
 229
 230   /* Round 3 */
 231   HH (a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33 */
 232   HH (d, a, b, c, x[ 8], S32, 0x8771f681); /* 34 */
 233   HH (c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */
 234   HH (b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */
 235   HH (a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37 */
 236   HH (d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38 */
 237   HH (c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39 */
 238   HH (b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */
 239   HH (a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */
 240   HH (d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42 */
 241   HH (c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43 */
 242   HH (b, c, d, a, x[ 6], S34,  0x4881d05); /* 44 */
 243   HH (a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45 */
 244   HH (d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */
 245   HH (c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */
 246   HH (b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48 */
 247
 248   /* Round 4 */
 249   II (a, b, c, d, x[ 0], S41, 0xf4292244); /* 49 */
 250   II (d, a, b, c, x[ 7], S42, 0x432aff97); /* 50 */
 251   II (c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */
 252   II (b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52 */
 253   II (a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */
 254   II (d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54 */
 255   II (c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */
 256   II (b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56 */
 257   II (a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57 */
 258   II (d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */
 259   II (c, d, a, b, x[ 6], S43, 0xa3014314); /* 59 */
 260   II (b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */
 261   II (a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61 */
 262   II (d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */
 263   II (c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63 */
 264   II (b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64 */
 265
 266   state[0] += a;
 267   state[1] += b;
 268   state[2] += c;
 269   state[3] += d;
 270
 271   /* Zeroize sensitive information.
 272 */
 273   MD5_memset ((POINTER)x, 0, sizeof (x));
 274 }
 275
 276 /* Encodes input (UINT4) into output (unsigned char). Assumes len is
 277   a multiple of 4.
 278  */
 279 static void Encode (output, input, len)
 280 unsigned char *output;
 281 UINT4 *input;
 282 unsigned int len;
 283 {
 284   unsigned int i, j;
 285
 286   for (i = 0, j = 0; j < len; i++, j += 4) {
 287  output[j] = (unsigned char)(input[i] & 0xff);
 288  output[j+1] = (unsigned char)((input[i] >> 8) & 0xff);
 289  output[j+2] = (unsigned char)((input[i] >> 16) & 0xff);
 290  output[j+3] = (unsigned char)((input[i] >> 24) & 0xff);
 291   }
 292 }
 293
 294 /* Decodes input (unsigned char) into output (UINT4). Assumes len is
 295   a multiple of 4.
 296  */
 297 static void Decode (output, input, len)
 298 UINT4 *output;
 299 unsigned char *input;
 300 unsigned int len;
 301 {
 302   unsigned int i, j;
 303
 304   for (i = 0, j = 0; j < len; i++, j += 4)
 305  output[i] = ((UINT4)input[j]) | (((UINT4)input[j+1]) << 8) |
 306    (((UINT4)input[j+2]) << 16) | (((UINT4)input[j+3]) << 24);
 307 }
 308
 309 /* Note: Replace "for loop" with standard memcpy if possible.
 310  */
 311
 312 static void MD5_memcpy (output, input, len)
 313 POINTER output;
 314 POINTER input;
 315 unsigned int len;
 316 {
 317   unsigned int i;
 318
 319   for (i = 0; i < len; i++)
 320  output[i] = input[i];
 321 }
 322
 323 /* Note: Replace "for loop" with standard memset if possible.
 324  */
 325 static void MD5_memset (output, value, len)
 326 POINTER output;
 327 int value;
 328 unsigned int len;
 329 {
 330   unsigned int i;
 331
 332   for (i = 0; i < len; i++)
 333  ((char *)output)[i] = (char)value;
 334 }