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  * This code is the same as the code published by RSA Inc.  It has been
  26  * edited for clarity and style only.
  27  */
  28
  29 #include <sys/cdefs.h>
  30 __FBSDID("$FreeBSD$");
  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 <machine/endian.h>
  41 #include <sys/endian.h>
  42 #include "md5.h"
  43
  44 static void MD5Transform(u_int32_t [4], const unsigned char [64]);
  45
  46 #ifdef _KERNEL
  47 #define memset(x,y,z)   bzero(x,z);
  48 #define memcpy(x,y,z)   bcopy(y, x, z)
  49 #endif
  50
  51 #if (BYTE_ORDER == LITTLE_ENDIAN)
  52 #define Encode memcpy
  53 #define Decode memcpy
  54 #else
  55
  56 /*
  57  * Encodes input (u_int32_t) into output (unsigned char). Assumes len is
  58  * a multiple of 4.
  59  */
  60
  61 static void
  62 Encode (unsigned char *output, u_int32_t *input, unsigned int len)
  63 {
  64         unsigned int i;
  65         u_int32_t *op = (u_int32_t *)output;
  66
  67         for (i = 0; i < len / 4; i++)
  68                 op[i] = htole32(input[i]);
  69 }
  70
  71 /*
  72  * Decodes input (unsigned char) into output (u_int32_t). Assumes len is
  73  * a multiple of 4.
  74  */
  75
  76 static void
  77 Decode (u_int32_t *output, const unsigned char *input, unsigned int len)
  78 {
  79         unsigned int i;
  80         const u_int32_t *ip = (const u_int32_t *)input;
  81
  82         for (i = 0; i < len / 4; i++)
  83                 output[i] = le32toh(ip[i]);
  84 }
  85 #endif
  86
  87 static unsigned char PADDING[64] = {
  88   0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  89   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  90   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
  91 };
  92
  93 /* F, G, H and I are basic MD5 functions. */
  94 #define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
  95 #define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
  96 #define H(x, y, z) ((x) ^ (y) ^ (z))
  97 #define I(x, y, z) ((y) ^ ((x) | (~z)))
  98
  99 /* ROTATE_LEFT rotates x left n bits. */
 100 #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
 101
 102 /*
 103  * FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4.
 104  * Rotation is separate from addition to prevent recomputation.
 105  */
 106 #define FF(a, b, c, d, x, s, ac) { \
 107         (a) += F ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
 108         (a) = ROTATE_LEFT ((a), (s)); \
 109         (a) += (b); \
 110         }
 111 #define GG(a, b, c, d, x, s, ac) { \
 112         (a) += G ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
 113         (a) = ROTATE_LEFT ((a), (s)); \
 114         (a) += (b); \
 115         }
 116 #define HH(a, b, c, d, x, s, ac) { \
 117         (a) += H ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
 118         (a) = ROTATE_LEFT ((a), (s)); \
 119         (a) += (b); \
 120         }
 121 #define II(a, b, c, d, x, s, ac) { \
 122         (a) += I ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
 123         (a) = ROTATE_LEFT ((a), (s)); \
 124         (a) += (b); \
 125         }
 126
 127 /* MD5 initialization. Begins an MD5 operation, writing a new context. */
 128
 129 void
 130 MD5Init (context)
 131         MD5_CTX *context;
 132 {
 133
 134         context->count[0] = context->count[1] = 0;
 135
 136         /* Load magic initialization constants.  */
 137         context->state[0] = 0x67452301;
 138         context->state[1] = 0xefcdab89;
 139         context->state[2] = 0x98badcfe;
 140         context->state[3] = 0x10325476;
 141 }
 142
 143 /*
 144  * MD5 block update operation. Continues an MD5 message-digest
 145  * operation, processing another message block, and updating the
 146  * context.
 147  */
 148
 149 void
 150 MD5Update (context, in, inputLen)
 151         MD5_CTX *context;
 152         const void *in;
 153         unsigned int inputLen;
 154 {
 155         unsigned int i, idx, partLen;
 156         const unsigned char *input = in;
 157
 158         /* Compute number of bytes mod 64 */
 159         idx = (unsigned int)((context->count[0] >> 3) & 0x3F);
 160
 161         /* Update number of bits */
 162         if ((context->count[0] += ((u_int32_t)inputLen << 3))
 163             < ((u_int32_t)inputLen << 3))
 164                 context->count[1]++;
 165         context->count[1] += ((u_int32_t)inputLen >> 29);
 166
 167         partLen = 64 - idx;
 168
 169         /* Transform as many times as possible. */
 170         if (inputLen >= partLen) {
 171                 memcpy((void *)&context->buffer[idx], (const void *)input,
 172                     partLen);
 173                 MD5Transform (context->state, context->buffer);
 174
 175                 for (i = partLen; i + 63 < inputLen; i += 64)
 176                         MD5Transform (context->state, &input[i]);
 177
 178                 idx = 0;
 179         }
 180         else
 181                 i = 0;
 182
 183         /* Buffer remaining input */
 184         memcpy ((void *)&context->buffer[idx], (const void *)&input[i],
 185             inputLen-i);
 186 }
 187
 188 /*
 189  * MD5 padding. Adds padding followed by original length.
 190  */
 191
 192 void
 193 MD5Pad (context)
 194         MD5_CTX *context;
 195 {
 196         unsigned char bits[8];
 197         unsigned int idx, padLen;
 198
 199         /* Save number of bits */
 200         Encode (bits, context->count, 8);
 201
 202         /* Pad out to 56 mod 64. */
 203         idx = (unsigned int)((context->count[0] >> 3) & 0x3f);
 204         padLen = (idx < 56) ? (56 - idx) : (120 - idx);
 205         MD5Update (context, PADDING, padLen);
 206
 207         /* Append length (before padding) */
 208         MD5Update (context, bits, 8);
 209 }
 210
 211 /*
 212  * MD5 finalization. Ends an MD5 message-digest operation, writing the
 213  * the message digest and zeroizing the context.
 214  */
 215
 216 void
 217 MD5Final (digest, context)
 218         unsigned char digest[16];
 219         MD5_CTX *context;
 220 {
 221         /* Do padding. */
 222         MD5Pad (context);
 223
 224         /* Store state in digest */
 225         Encode (digest, context->state, 16);
 226
 227         /* Zeroize sensitive information. */
 228         memset ((void *)context, 0, sizeof (*context));
 229 }
 230
 231 /* MD5 basic transformation. Transforms state based on block. */
 232
 233 static void
 234 MD5Transform (state, block)
 235         u_int32_t state[4];
 236         const unsigned char block[64];
 237 {
 238         u_int32_t a = state[0], b = state[1], c = state[2], d = state[3], x[16];
 239
 240         Decode (x, block, 64);
 241
 242         /* Round 1 */
 243 #define S11 7
 244 #define S12 12
 245 #define S13 17
 246 #define S14 22
 247         FF (a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1 */
 248         FF (d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2 */
 249         FF (c, d, a, b, x[ 2], S13, 0x242070db); /* 3 */
 250         FF (b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4 */
 251         FF (a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5 */
 252         FF (d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6 */
 253         FF (c, d, a, b, x[ 6], S13, 0xa8304613); /* 7 */
 254         FF (b, c, d, a, x[ 7], S14, 0xfd469501); /* 8 */
 255         FF (a, b, c, d, x[ 8], S11, 0x698098d8); /* 9 */
 256         FF (d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10 */
 257         FF (c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */
 258         FF (b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */
 259         FF (a, b, c, d, x[12], S11, 0x6b901122); /* 13 */
 260         FF (d, a, b, c, x[13], S12, 0xfd987193); /* 14 */
 261         FF (c, d, a, b, x[14], S13, 0xa679438e); /* 15 */
 262         FF (b, c, d, a, x[15], S14, 0x49b40821); /* 16 */
 263
 264         /* Round 2 */
 265 #define S21 5
 266 #define S22 9
 267 #define S23 14
 268 #define S24 20
 269         GG (a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17 */
 270         GG (d, a, b, c, x[ 6], S22, 0xc040b340); /* 18 */
 271         GG (c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */
 272         GG (b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20 */
 273         GG (a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21 */
 274         GG (d, a, b, c, x[10], S22,  0x2441453); /* 22 */
 275         GG (c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */
 276         GG (b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24 */
 277         GG (a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25 */
 278         GG (d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */
 279         GG (c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27 */
 280         GG (b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28 */
 281         GG (a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */
 282         GG (d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30 */
 283         GG (c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31 */
 284         GG (b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */
 285
 286         /* Round 3 */
 287 #define S31 4
 288 #define S32 11
 289 #define S33 16
 290 #define S34 23
 291         HH (a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33 */
 292         HH (d, a, b, c, x[ 8], S32, 0x8771f681); /* 34 */
 293         HH (c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */
 294         HH (b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */
 295         HH (a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37 */
 296         HH (d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38 */
 297         HH (c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39 */
 298         HH (b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */
 299         HH (a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */
 300         HH (d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42 */
 301         HH (c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43 */
 302         HH (b, c, d, a, x[ 6], S34,  0x4881d05); /* 44 */
 303         HH (a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45 */
 304         HH (d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */
 305         HH (c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */
 306         HH (b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48 */
 307
 308         /* Round 4 */
 309 #define S41 6
 310 #define S42 10
 311 #define S43 15
 312 #define S44 21
 313         II (a, b, c, d, x[ 0], S41, 0xf4292244); /* 49 */
 314         II (d, a, b, c, x[ 7], S42, 0x432aff97); /* 50 */
 315         II (c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */
 316         II (b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52 */
 317         II (a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */
 318         II (d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54 */
 319         II (c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */
 320         II (b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56 */
 321         II (a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57 */
 322         II (d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */
 323         II (c, d, a, b, x[ 6], S43, 0xa3014314); /* 59 */
 324         II (b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */
 325         II (a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61 */
 326         II (d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */
 327         II (c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63 */
 328         II (b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64 */
 329
 330         state[0] += a;
 331         state[1] += b;
 332         state[2] += c;
 333         state[3] += d;
 334
 335         /* Zeroize sensitive information. */
 336         memset ((void *)x, 0, sizeof (x));
 337 }
 338
 339 #ifdef WEAK_REFS
 340 /* When building libmd, provide weak references. Note: this is not
 341    activated in the context of compiling these sources for internal
 342    use in libcrypt.
 343  */
 344 #undef MD5Init
 345 __weak_reference(_libmd_MD5Init, MD5Init);
 346 #undef MD5Update
 347 __weak_reference(_libmd_MD5Update, MD5Update);
 348 #undef MD5Pad
 349 __weak_reference(_libmd_MD5Pad, MD5Pad);
 350 #undef MD5Final
 351 __weak_reference(_libmd_MD5Final, MD5Final);
 352 #undef MD5Transform
 353 __weak_reference(_libmd_MD5Transform, MD5Transform);
 354 #endif