lib/libmd/md5c.c

   1 /*
   2  * MD5C.C - RSA Data Security, Inc., MD5 message-digest algorithm
   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  * $FreeBSD: src/lib/libmd/md5c.c,v 1.11 1999/12/29 05:04:20 peter Exp $
  26  * $DragonFly: src/lib/libmd/md5c.c,v 1.3 2003/11/12 20:21:31 eirikn Exp $
  27  *
  28  * This code is the same as the code published by RSA Inc.  It has been
  29  * edited for clarity and style only.
  30  */
  31
  32 #include <sys/types.h>
  33
  34 #ifdef _KERNEL
  35 #include <sys/systm.h>
  36 #else
  37 #include <string.h>
  38 #endif
  39
  40 #include <sys/md5.h>
  41
  42 static void MD5Transform (u_int32_t [4], const unsigned char [64]);
  43
  44 #ifdef _KERNEL
  45 #define memset(x,y,z)   bzero(x,z);
  46 #define memcpy(x,y,z)   bcopy(y, x, z)
  47 #endif
  48
  49 #ifdef i386
  50 #define Encode memcpy
  51 #define Decode memcpy
  52 #else /* i386 */
  53
  54 /*
  55  * Encodes input (u_int32_t) into output (unsigned char). Assumes len is
  56  * a multiple of 4.
  57  */
  58
  59 static void
  60 Encode (output, input, len)
  61         unsigned char *output;
  62         u_int32_t *input;
  63         unsigned int len;
  64 {
  65         unsigned int i, j;
  66
  67         for (i = 0, j = 0; j < len; i++, j += 4) {
  68                 output[j] = (unsigned char)(input[i] & 0xff);
  69                 output[j+1] = (unsigned char)((input[i] >> 8) & 0xff);
  70                 output[j+2] = (unsigned char)((input[i] >> 16) & 0xff);
  71                 output[j+3] = (unsigned char)((input[i] >> 24) & 0xff);
  72         }
  73 }
  74
  75 /*
  76  * Decodes input (unsigned char) into output (u_int32_t). Assumes len is
  77  * a multiple of 4.
  78  */
  79
  80 static void
  81 Decode (output, input, len)
  82         u_int32_t *output;
  83         const unsigned char *input;
  84         unsigned int len;
  85 {
  86         unsigned int i, j;
  87
  88         for (i = 0, j = 0; j < len; i++, j += 4)
  89                 output[i] = ((u_int32_t)input[j]) | (((u_int32_t)input[j+1]) << 8) |
  90                     (((u_int32_t)input[j+2]) << 16) | (((u_int32_t)input[j+3]) << 24);
  91 }
  92 #endif /* i386 */
  93
  94 static unsigned char PADDING[64] = {
  95   0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  96   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  97   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
  98 };
  99
 100 /* F, G, H and I are basic MD5 functions. */
 101 #define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
 102 #define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
 103 #define H(x, y, z) ((x) ^ (y) ^ (z))
 104 #define I(x, y, z) ((y) ^ ((x) | (~z)))
 105
 106 /* ROTATE_LEFT rotates x left n bits. */
 107 #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
 108
 109 /*
 110  * FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4.
 111  * Rotation is separate from addition to prevent recomputation.
 112  */
 113 #define FF(a, b, c, d, x, s, ac) { \
 114         (a) += F ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
 115         (a) = ROTATE_LEFT ((a), (s)); \
 116         (a) += (b); \
 117         }
 118 #define GG(a, b, c, d, x, s, ac) { \
 119         (a) += G ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
 120         (a) = ROTATE_LEFT ((a), (s)); \
 121         (a) += (b); \
 122         }
 123 #define HH(a, b, c, d, x, s, ac) { \
 124         (a) += H ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
 125         (a) = ROTATE_LEFT ((a), (s)); \
 126         (a) += (b); \
 127         }
 128 #define II(a, b, c, d, x, s, ac) { \
 129         (a) += I ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
 130         (a) = ROTATE_LEFT ((a), (s)); \
 131         (a) += (b); \
 132         }
 133
 134 /* MD5 initialization. Begins an MD5 operation, writing a new context. */
 135
 136 void
 137 MD5Init (context)
 138         MD5_CTX *context;
 139 {
 140
 141         context->count[0] = context->count[1] = 0;
 142
 143         /* Load magic initialization constants.  */
 144         context->state[0] = 0x67452301;
 145         context->state[1] = 0xefcdab89;
 146         context->state[2] = 0x98badcfe;
 147         context->state[3] = 0x10325476;
 148 }
 149
 150 /*
 151  * MD5 block update operation. Continues an MD5 message-digest
 152  * operation, processing another message block, and updating the
 153  * context.
 154  */
 155
 156 void
 157 MD5Update (context, input, inputLen)
 158         MD5_CTX *context;
 159         const unsigned char *input;
 160         unsigned int inputLen;
 161 {
 162         unsigned int i, index, partLen;
 163
 164         /* Compute number of bytes mod 64 */
 165         index = (unsigned int)((context->count[0] >> 3) & 0x3F);
 166
 167         /* Update number of bits */
 168         if ((context->count[0] += ((u_int32_t)inputLen << 3))
 169             < ((u_int32_t)inputLen << 3))
 170                 context->count[1]++;
 171         context->count[1] += ((u_int32_t)inputLen >> 29);
 172
 173         partLen = 64 - index;
 174
 175         /* Transform as many times as possible. */
 176         if (inputLen >= partLen) {
 177                 memcpy((void *)&context->buffer[index], (const void *)input,
 178                     partLen);
 179                 MD5Transform (context->state, context->buffer);
 180
 181                 for (i = partLen; i + 63 < inputLen; i += 64)
 182                         MD5Transform (context->state, &input[i]);
 183
 184                 index = 0;
 185         }
 186         else
 187                 i = 0;
 188
 189         /* Buffer remaining input */
 190         memcpy ((void *)&context->buffer[index], (const void *)&input[i],
 191             inputLen-i);
 192 }
 193
 194 /*
 195  * MD5 padding. Adds padding followed by original length.
 196  */
 197
 198 void
 199 MD5Pad (context)
 200         MD5_CTX *context;
 201 {
 202         unsigned char bits[8];
 203         unsigned int index, padLen;
 204
 205         /* Save number of bits */
 206         Encode (bits, context->count, 8);
 207
 208         /* Pad out to 56 mod 64. */
 209         index = (unsigned int)((context->count[0] >> 3) & 0x3f);
 210         padLen = (index < 56) ? (56 - index) : (120 - index);
 211         MD5Update (context, PADDING, padLen);
 212
 213         /* Append length (before padding) */
 214         MD5Update (context, bits, 8);
 215 }
 216
 217 /*
 218  * MD5 finalization. Ends an MD5 message-digest operation, writing the
 219  * the message digest and zeroizing the context.
 220  */
 221
 222 void
 223 MD5Final (digest, context)
 224         unsigned char digest[16];
 225         MD5_CTX *context;
 226 {
 227         /* Do padding. */
 228         MD5Pad (context);
 229
 230         /* Store state in digest */
 231         Encode (digest, context->state, 16);
 232
 233         /* Zeroize sensitive information. */
 234         memset ((void *)context, 0, sizeof (*context));
 235 }
 236
 237 /* MD5 basic transformation. Transforms state based on block. */
 238
 239 static void
 240 MD5Transform (state, block)
 241         u_int32_t state[4];
 242         const unsigned char block[64];
 243 {
 244         u_int32_t a = state[0], b = state[1], c = state[2], d = state[3], x[16];
 245
 246         Decode (x, block, 64);
 247
 248         /* Round 1 */
 249 #define S11 7
 250 #define S12 12
 251 #define S13 17
 252 #define S14 22
 253         FF (a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1 */
 254         FF (d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2 */
 255         FF (c, d, a, b, x[ 2], S13, 0x242070db); /* 3 */
 256         FF (b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4 */
 257         FF (a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5 */
 258         FF (d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6 */
 259         FF (c, d, a, b, x[ 6], S13, 0xa8304613); /* 7 */
 260         FF (b, c, d, a, x[ 7], S14, 0xfd469501); /* 8 */
 261         FF (a, b, c, d, x[ 8], S11, 0x698098d8); /* 9 */
 262         FF (d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10 */
 263         FF (c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */
 264         FF (b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */
 265         FF (a, b, c, d, x[12], S11, 0x6b901122); /* 13 */
 266         FF (d, a, b, c, x[13], S12, 0xfd987193); /* 14 */
 267         FF (c, d, a, b, x[14], S13, 0xa679438e); /* 15 */
 268         FF (b, c, d, a, x[15], S14, 0x49b40821); /* 16 */
 269
 270         /* Round 2 */
 271 #define S21 5
 272 #define S22 9
 273 #define S23 14
 274 #define S24 20
 275         GG (a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17 */
 276         GG (d, a, b, c, x[ 6], S22, 0xc040b340); /* 18 */
 277         GG (c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */
 278         GG (b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20 */
 279         GG (a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21 */
 280         GG (d, a, b, c, x[10], S22,  0x2441453); /* 22 */
 281         GG (c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */
 282         GG (b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24 */
 283         GG (a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25 */
 284         GG (d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */
 285         GG (c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27 */
 286         GG (b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28 */
 287         GG (a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */
 288         GG (d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30 */
 289         GG (c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31 */
 290         GG (b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */
 291
 292         /* Round 3 */
 293 #define S31 4
 294 #define S32 11
 295 #define S33 16
 296 #define S34 23
 297         HH (a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33 */
 298         HH (d, a, b, c, x[ 8], S32, 0x8771f681); /* 34 */
 299         HH (c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */
 300         HH (b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */
 301         HH (a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37 */
 302         HH (d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38 */
 303         HH (c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39 */
 304         HH (b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */
 305         HH (a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */
 306         HH (d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42 */
 307         HH (c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43 */
 308         HH (b, c, d, a, x[ 6], S34,  0x4881d05); /* 44 */
 309         HH (a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45 */
 310         HH (d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */
 311         HH (c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */
 312         HH (b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48 */
 313
 314         /* Round 4 */
 315 #define S41 6
 316 #define S42 10
 317 #define S43 15
 318 #define S44 21
 319         II (a, b, c, d, x[ 0], S41, 0xf4292244); /* 49 */
 320         II (d, a, b, c, x[ 7], S42, 0x432aff97); /* 50 */
 321         II (c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */
 322         II (b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52 */
 323         II (a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */
 324         II (d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54 */
 325         II (c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */
 326         II (b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56 */
 327         II (a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57 */
 328         II (d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */
 329         II (c, d, a, b, x[ 6], S43, 0xa3014314); /* 59 */
 330         II (b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */
 331         II (a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61 */
 332         II (d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */
 333         II (c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63 */
 334         II (b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64 */
 335
 336         state[0] += a;
 337         state[1] += b;
 338         state[2] += c;
 339         state[3] += d;
 340
 341         /* Zeroize sensitive information. */
 342         memset ((void *)x, 0, sizeof (x));
 343 }