AppleCSP/MiscCSPAlgs/MD5.c

   1 /*
   2         File:           MD5.c
   3
   4         Written by:     Colin Plumb
   5
   6         Copyright:      Copyright 1998 by Apple Computer, Inc., all rights reserved.
   7
   8         Change History (most recent first):
   9
  10                  <7>    10/06/98        ap              Changed to compile with C++.
  11
  12         To Do:
  13 */
  14
  15 /* Copyright (c) 1998 Apple Computer, Inc.  All rights reserved.
  16  *
  17  * NOTICE: USE OF THE MATERIALS ACCOMPANYING THIS NOTICE IS SUBJECT
  18  * TO THE TERMS OF THE SIGNED "FAST ELLIPTIC ENCRYPTION (FEE) REFERENCE
  19  * SOURCE CODE EVALUATION AGREEMENT" BETWEEN APPLE COMPUTER, INC. AND THE
  20  * ORIGINAL LICENSEE THAT OBTAINED THESE MATERIALS FROM APPLE COMPUTER,
  21  * INC.  ANY USE OF THESE MATERIALS NOT PERMITTED BY SUCH AGREEMENT WILL
  22  * EXPOSE YOU TO LIABILITY.
  23  ***************************************************************************
  24  *
  25  * MD5.c
  26  */
  27
  28 /*
  29  * This code implements the MD5 message-digest algorithm.
  30  * The algorithm is due to Ron Rivest.  This code was
  31  * written by Colin Plumb in 1993, no copyright is claimed.
  32  * This code is in the public domain; do with it what you wish.
  33  *
  34  * Equivalent code is available from RSA Data Security, Inc.
  35  * This code has been tested against that, and is equivalent,
  36  * except that you don't need to include two pages of legalese
  37  * with every copy.
  38  *
  39  * To compute the message digest of a chunk of bytes, declare an
  40  * MD5Context structure, pass it to MD5Init, call MD5Update as
  41  * needed on buffers full of bytes, and then call MD5Final, which
  42  * will fill a supplied 16-byte array with the digest.
  43  */
  44
  45 /*
  46  * Revision History
  47  * ----------------
  48  * 06 Feb 1997  Doug Mitchell at Apple
  49  *      Fixed endian-dependent cast in MD5Final()
  50  *      Made byteReverse() tolerant of platform-dependent alignment
  51  *              restrictions
  52  */
  53
  54 #include "MD5.h"
  55 #include "platform.h"
  56 #include <stdlib.h>
  57
  58 static inline void intToByteRep(int i, unsigned char *buf)
  59 {
  60         *buf++ = (unsigned char)((i >> 24) & 0xff);
  61         *buf++ = (unsigned char)((i >> 16) & 0xff);
  62         *buf++ = (unsigned char)((i >> 8)  & 0xff);
  63         *buf   = (unsigned char)(i & 0xff);
  64 }
  65
  66 #define MD5_DEBUG       0
  67
  68 #if     MD5_DEBUG
  69 static inline void dumpCtx(struct MD5Context *ctx, char *label)
  70 {
  71         int i;
  72
  73         printf("%s\n", label);
  74         printf("buf = ");
  75         for(i=0; i<4; i++) {
  76                 printf("%x:", ctx->buf[i]);
  77         }
  78         printf("\nbits: %d:%d\n", ctx->bits[0], ctx->bits[1]);
  79         printf("in[]:\n   ");
  80         for(i=0; i<64; i++) {
  81                 printf("%02x:", ctx->in[i]);
  82                 if((i % 16) == 15) {
  83                         printf("\n   ");
  84                 }
  85         }
  86         printf("\n");
  87 }
  88 #else   // MD5_DEBUG
  89 #define dumpCtx(ctx, label)
  90 #endif  // MD5_DEBUG
  91
  92 static void MD5Transform(uint32 buf[4], uint32 const in[16]);
  93
  94 #if __LITTLE_ENDIAN__
  95 #define byteReverse(buf, len)   /* Nothing */
  96 #else
  97 static void byteReverse(unsigned char *buf, unsigned longs);
  98
  99 #ifndef ASM_MD5
 100 /*
 101  * Note: this code is harmless on little-endian machines.
 102  */
 103 static void byteReverse(unsigned char *buf, unsigned longs)
 104 {
 105 #if             old_way
 106     /*
 107      * this code is NOT harmless on big-endian machine which require
 108      * natural alignment.
 109      */
 110     uint32 t;
 111     do {
 112         t = (uint32) ((unsigned) buf[3] << 8 | buf[2]) << 16 |
 113             ((unsigned) buf[1] << 8 | buf[0]);
 114         *(uint32 *) buf = t;
 115         buf += 4;
 116     } while (--longs);
 117 #else   // new_way
 118
 119     unsigned char t;
 120     do {
 121         t = buf[0];
 122         buf[0] = buf[3];
 123         buf[3] = t;
 124         t = buf[1];
 125         buf[1] = buf[2];
 126         buf[2] = t;
 127         buf += 4;
 128     } while (--longs);
 129 #endif // old_way
 130 }
 131 #endif // ASM_MD5
 132 #endif // __LITTLE_ENDIAN__
 133
 134 /*
 135  * Start MD5 accumulation.  Set bit count to 0 and buffer to mysterious
 136  * initialization constants.
 137  */
 138 void MD5Init(struct MD5Context *ctx)
 139 {
 140     ctx->buf[0] = 0x67452301;
 141     ctx->buf[1] = 0xefcdab89;
 142     ctx->buf[2] = 0x98badcfe;
 143     ctx->buf[3] = 0x10325476;
 144
 145     ctx->bits[0] = 0;
 146     ctx->bits[1] = 0;
 147 }
 148
 149 /*
 150  * Update context to reflect the concatenation of another buffer full
 151  * of bytes.
 152  */
 153 void MD5Update(struct MD5Context *ctx, unsigned char const *buf, unsigned len)
 154 {
 155     uint32 t;
 156
 157     dumpCtx(ctx, "MD5.c update top");
 158     /* Update bitcount */
 159
 160     t = ctx->bits[0];
 161     if ((ctx->bits[0] = t + ((uint32) len << 3)) < t)
 162         ctx->bits[1]++;         /* Carry from low to high */
 163     ctx->bits[1] += len >> 29;
 164
 165     t = (t >> 3) & 0x3f;        /* Bytes already in shsInfo->data */
 166
 167     /* Handle any leading odd-sized chunks */
 168
 169     if (t) {
 170         unsigned char *p = (unsigned char *) ctx->in + t;
 171
 172         t = 64 - t;
 173         if (len < t) {
 174             memcpy(p, buf, len);
 175             return;
 176         }
 177         memcpy(p, buf, t);
 178         byteReverse(ctx->in, 16);
 179         MD5Transform(ctx->buf, (uint32 *) ctx->in);
 180         dumpCtx(ctx, "update - return from transform (1)");
 181         buf += t;
 182         len -= t;
 183     }
 184     /* Process data in 64-byte chunks */
 185
 186     while (len >= 64) {
 187         memcpy(ctx->in, buf, 64);
 188         byteReverse(ctx->in, 16);
 189         MD5Transform(ctx->buf, (uint32 *) ctx->in);
 190         dumpCtx(ctx, "update - return from transform (2)");
 191         buf += 64;
 192         len -= 64;
 193     }
 194
 195     /* Handle any remaining bytes of data. */
 196
 197     memcpy(ctx->in, buf, len);
 198 }
 199
 200 /*
 201  * Final wrapup - pad to 64-byte boundary with the bit pattern
 202  * 1 0* (64-bit count of bits processed, MSB-first)
 203  */
 204 void MD5Final(struct MD5Context *ctx, unsigned char *digest)
 205 {
 206     unsigned count;
 207     unsigned char *p;
 208
 209     dumpCtx(ctx, "final top");
 210
 211     /* Compute number of bytes mod 64 */
 212     count = (ctx->bits[0] >> 3) & 0x3F;
 213
 214     /* Set the first char of padding to 0x80.  This is safe since there is
 215        always at least one byte free */
 216     p = ctx->in + count;
 217     *p++ = 0x80;
 218     #if MD5_DEBUG
 219     printf("in[%d] = %x\n", count, ctx->in[count]);
 220     #endif
 221     /* Bytes of padding needed to make 64 bytes */
 222     count = 64 - 1 - count;
 223
 224     /* Pad out to 56 mod 64 */
 225     dumpCtx(ctx, "final, before pad");
 226     if (count < 8) {
 227         /* Two lots of padding:  Pad the first block to 64 bytes */
 228         bzero(p, count);
 229         byteReverse(ctx->in, 16);
 230         MD5Transform(ctx->buf, (uint32 *) ctx->in);
 231
 232         /* Now fill the next block with 56 bytes */
 233         bzero(ctx->in, 56);
 234     } else {
 235         /* Pad block to 56 bytes */
 236         bzero(p, count - 8);
 237     }
 238     byteReverse(ctx->in, 14);
 239
 240     /* Append length in bits and transform */
 241     #if         old_way
 242      /*
 243      * On a little endian machine, this writes the l.s. byte of
 244      * the bit count to ctx->in[56] and the m.s byte of the bit count to
 245      * ctx->in[63].
 246      */
 247     ((uint32 *) ctx->in)[14] = ctx->bits[0];
 248     ((uint32 *) ctx->in)[15] = ctx->bits[1];
 249     #else       // new_way
 250     intToByteRep(ctx->bits[0], &ctx->in[56]);
 251     intToByteRep(ctx->bits[1], &ctx->in[60]);
 252     #endif      // new_way
 253
 254     dumpCtx(ctx, "last transform");
 255     MD5Transform(ctx->buf, (uint32 *) ctx->in);
 256     byteReverse((unsigned char *) ctx->buf, 4);
 257     memcpy(digest, ctx->buf, MD5_DIGEST_SIZE);
 258     dumpCtx(ctx, "final end");
 259
 260     bzero(ctx, sizeof(ctx));    /* In case it's sensitive */
 261 }
 262
 263 #ifndef ASM_MD5
 264
 265 /* The four core functions - F1 is optimized somewhat */
 266
 267 /* #define F1(x, y, z) (x & y | ~x & z) */
 268 #define F1(x, y, z) (z ^ (x & (y ^ z)))
 269 #define F2(x, y, z) F1(z, x, y)
 270 #define F3(x, y, z) (x ^ y ^ z)
 271 #define F4(x, y, z) (y ^ (x | ~z))
 272
 273 /* This is the central step in the MD5 algorithm. */
 274 #define MD5STEP(f, w, x, y, z, data, s) \
 275         ( w += f(x, y, z) + data,  w = w<<s | w>>(32-s),  w += x )
 276
 277 /*
 278  * The core of the MD5 algorithm, this alters an existing MD5 hash to
 279  * reflect the addition of 16 longwords of new data.  MD5Update blocks
 280  * the data and converts bytes into longwords for this routine.
 281  */
 282 static void MD5Transform(uint32 buf[4], uint32 const in[16])
 283 {
 284     register uint32 a, b, c, d;
 285
 286     a = buf[0];
 287     b = buf[1];
 288     c = buf[2];
 289     d = buf[3];
 290
 291     MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
 292     MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
 293     MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
 294     MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
 295     MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
 296     MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
 297     MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
 298     MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
 299     MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
 300     MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
 301     MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
 302     MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
 303     MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
 304     MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
 305     MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
 306     MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
 307
 308     MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
 309     MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
 310     MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
 311     MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
 312     MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
 313     MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
 314     MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
 315     MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
 316     MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
 317     MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
 318     MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
 319     MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
 320     MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
 321     MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
 322     MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
 323     MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
 324
 325     MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
 326     MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
 327     MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
 328     MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
 329     MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
 330     MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
 331     MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
 332     MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
 333     MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
 334     MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
 335     MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
 336     MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
 337     MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
 338     MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
 339     MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
 340     MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
 341
 342     MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
 343     MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
 344     MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
 345     MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
 346     MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
 347     MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
 348     MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
 349     MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
 350     MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
 351     MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
 352     MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
 353     MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
 354     MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
 355     MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
 356     MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
 357     MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
 358
 359     buf[0] += a;
 360     buf[1] += b;
 361     buf[2] += c;
 362     buf[3] += d;
 363 }
 364
 365 #endif // ASM_MD5