src/common/md5.c

   1 /* md5.c - MD5 Message-Digest Algorithm
   2  *      Copyright (C) 1995, 1996, 1998, 1999 Free Software Foundation, Inc.
   3  *
   4  * according to the definition of MD5 in RFC 1321 from April 1992.
   5  * NOTE: This is *not* the same file as the one from glibc.
   6  *
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License as published by the
   9  * Free Software Foundation; either version 3, or (at your option) any
  10  * later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  19  */
  20 /* Written by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1995.  */
  21 /* heavily modified for GnuPG by <werner.koch@guug.de> */
  22 /* modified again for Sylpheed by <wk@gnupg.org> 2001-02-11 */
  23
  24
  25 /* Test values:
  26  * ""                  D4 1D 8C D9 8F 00 B2 04  E9 80 09 98 EC F8 42 7E
  27  * "a"                 0C C1 75 B9 C0 F1 B6 A8  31 C3 99 E2 69 77 26 61
  28  * "abc                90 01 50 98 3C D2 4F B0  D6 96 3F 7D 28 E1 7F 72
  29  * "message digest"    F9 6B 69 7D 7C B7 93 8D  52 5A 2F 31 AA F1 61 D0
  30  */
  31
  32 #include <config.h>
  33 #include <stdio.h>
  34 #include <stdlib.h>
  35 #include <string.h>
  36 #include <assert.h>
  37 #include <sys/types.h>
  38 #include <sys/stat.h>
  39 #include <fcntl.h>
  40 #include <unistd.h>
  41
  42 #include <glib.h>
  43 #include <glib/gstdio.h>
  44
  45 #include "md5.h"
  46
  47 /****************
  48  * Rotate a 32 bit integer by n bytes
  49  */
  50 #if defined(__GNUC__) && defined(__i386__)
  51 static inline guint32
  52 rol( guint32 x, int n)
  53 {
  54         __asm__("roll %%cl,%0"
  55                 :"=r" (x)
  56                 :"0" (x),"c" (n));
  57         return x;
  58 }
  59 #else
  60 #define rol(x,n) ( ((x) << (n)) | ((x) >> (32-(n))) )
  61 #endif
  62
  63 typedef struct {
  64     guint32 A,B,C,D;
  65     guint32  nblocks;
  66     unsigned char buf[64];
  67     int  count;
  68     int  finalized;
  69 } MD5_CONTEXT;
  70
  71 static void
  72 md5_init(MD5_CONTEXT *ctx)
  73 {
  74         ctx->A = 0x67452301;
  75         ctx->B = 0xefcdab89;
  76         ctx->C = 0x98badcfe;
  77         ctx->D = 0x10325476;
  78
  79         ctx->nblocks = 0;
  80         ctx->count = 0;
  81         ctx->finalized = 0;
  82 }
  83
  84 /* These are the four functions used in the four steps of the MD5 algorithm
  85    and defined in the RFC 1321.  The first function is a little bit optimized
  86    (as found in Colin Plumbs public domain implementation).  */
  87 /* #define FF(b, c, d) ((b & c) | (~b & d)) */
  88 #define FF(b, c, d) (d ^ (b & (c ^ d)))
  89 #define FG(b, c, d) FF (d, b, c)
  90 #define FH(b, c, d) (b ^ c ^ d)
  91 #define FI(b, c, d) (c ^ (b | ~d))
  92
  93
  94 /****************
  95  * transform n*64 bytes
  96  */
  97 static void
  98 transform(MD5_CONTEXT *ctx, const unsigned char *data)
  99 {
 100         guint32 correct_words[16];
 101         guint32 A = ctx->A;
 102         guint32 B = ctx->B;
 103         guint32 C = ctx->C;
 104         guint32 D = ctx->D;
 105         guint32 *cwp = correct_words;
 106
 107 #ifdef BIG_ENDIAN_HOST
 108         {
 109                 int i;
 110                 unsigned char *p2;
 111                 const unsigned char *p1;
 112
 113                 for (i = 0, p1 = data, p2 = (unsigned char*)correct_words;
 114                      i < 16; i++, p2 += 4) {
 115                         p2[3] = *p1++;
 116                         p2[2] = *p1++;
 117                         p2[1] = *p1++;
 118                         p2[0] = *p1++;
 119                 }
 120         }
 121 #else
 122         memcpy(correct_words, data, 64);
 123 #endif
 124
 125
 126 #define OP(a, b, c, d, s, T)                            \
 127         do {                                            \
 128                 a += FF (b, c, d) + (*cwp++) + T;       \
 129                 a = rol(a, s);                          \
 130                 a += b;                                 \
 131         } while (0)
 132
 133         /* Before we start, one word about the strange constants.
 134            They are defined in RFC 1321 as
 135
 136            T[i] = (int) (4294967296.0 * fabs (sin (i))), i=1..64
 137          */
 138
 139         /* Round 1.  */
 140         OP (A, B, C, D,  7, 0xd76aa478);
 141         OP (D, A, B, C, 12, 0xe8c7b756);
 142         OP (C, D, A, B, 17, 0x242070db);
 143         OP (B, C, D, A, 22, 0xc1bdceee);
 144         OP (A, B, C, D,  7, 0xf57c0faf);
 145         OP (D, A, B, C, 12, 0x4787c62a);
 146         OP (C, D, A, B, 17, 0xa8304613);
 147         OP (B, C, D, A, 22, 0xfd469501);
 148         OP (A, B, C, D,  7, 0x698098d8);
 149         OP (D, A, B, C, 12, 0x8b44f7af);
 150         OP (C, D, A, B, 17, 0xffff5bb1);
 151         OP (B, C, D, A, 22, 0x895cd7be);
 152         OP (A, B, C, D,  7, 0x6b901122);
 153         OP (D, A, B, C, 12, 0xfd987193);
 154         OP (C, D, A, B, 17, 0xa679438e);
 155         OP (B, C, D, A, 22, 0x49b40821);
 156
 157 #undef OP
 158 #define OP(f, a, b, c, d, k, s, T)  \
 159         do {                                                    \
 160                 a += f (b, c, d) + correct_words[k] + T;        \
 161                 a = rol(a, s);                                  \
 162                 a += b;                                         \
 163         } while (0)
 164
 165         /* Round 2.  */
 166         OP (FG, A, B, C, D,  1,  5, 0xf61e2562);
 167         OP (FG, D, A, B, C,  6,  9, 0xc040b340);
 168         OP (FG, C, D, A, B, 11, 14, 0x265e5a51);
 169         OP (FG, B, C, D, A,  0, 20, 0xe9b6c7aa);
 170         OP (FG, A, B, C, D,  5,  5, 0xd62f105d);
 171         OP (FG, D, A, B, C, 10,  9, 0x02441453);
 172         OP (FG, C, D, A, B, 15, 14, 0xd8a1e681);
 173         OP (FG, B, C, D, A,  4, 20, 0xe7d3fbc8);
 174         OP (FG, A, B, C, D,  9,  5, 0x21e1cde6);
 175         OP (FG, D, A, B, C, 14,  9, 0xc33707d6);
 176         OP (FG, C, D, A, B,  3, 14, 0xf4d50d87);
 177         OP (FG, B, C, D, A,  8, 20, 0x455a14ed);
 178         OP (FG, A, B, C, D, 13,  5, 0xa9e3e905);
 179         OP (FG, D, A, B, C,  2,  9, 0xfcefa3f8);
 180         OP (FG, C, D, A, B,  7, 14, 0x676f02d9);
 181         OP (FG, B, C, D, A, 12, 20, 0x8d2a4c8a);
 182
 183         /* Round 3.  */
 184         OP (FH, A, B, C, D,  5,  4, 0xfffa3942);
 185         OP (FH, D, A, B, C,  8, 11, 0x8771f681);
 186         OP (FH, C, D, A, B, 11, 16, 0x6d9d6122);
 187         OP (FH, B, C, D, A, 14, 23, 0xfde5380c);
 188         OP (FH, A, B, C, D,  1,  4, 0xa4beea44);
 189         OP (FH, D, A, B, C,  4, 11, 0x4bdecfa9);
 190         OP (FH, C, D, A, B,  7, 16, 0xf6bb4b60);
 191         OP (FH, B, C, D, A, 10, 23, 0xbebfbc70);
 192         OP (FH, A, B, C, D, 13,  4, 0x289b7ec6);
 193         OP (FH, D, A, B, C,  0, 11, 0xeaa127fa);
 194         OP (FH, C, D, A, B,  3, 16, 0xd4ef3085);
 195         OP (FH, B, C, D, A,  6, 23, 0x04881d05);
 196         OP (FH, A, B, C, D,  9,  4, 0xd9d4d039);
 197         OP (FH, D, A, B, C, 12, 11, 0xe6db99e5);
 198         OP (FH, C, D, A, B, 15, 16, 0x1fa27cf8);
 199         OP (FH, B, C, D, A,  2, 23, 0xc4ac5665);
 200
 201         /* Round 4.  */
 202         OP (FI, A, B, C, D,  0,  6, 0xf4292244);
 203         OP (FI, D, A, B, C,  7, 10, 0x432aff97);
 204         OP (FI, C, D, A, B, 14, 15, 0xab9423a7);
 205         OP (FI, B, C, D, A,  5, 21, 0xfc93a039);
 206         OP (FI, A, B, C, D, 12,  6, 0x655b59c3);
 207         OP (FI, D, A, B, C,  3, 10, 0x8f0ccc92);
 208         OP (FI, C, D, A, B, 10, 15, 0xffeff47d);
 209         OP (FI, B, C, D, A,  1, 21, 0x85845dd1);
 210         OP (FI, A, B, C, D,  8,  6, 0x6fa87e4f);
 211         OP (FI, D, A, B, C, 15, 10, 0xfe2ce6e0);
 212         OP (FI, C, D, A, B,  6, 15, 0xa3014314);
 213         OP (FI, B, C, D, A, 13, 21, 0x4e0811a1);
 214         OP (FI, A, B, C, D,  4,  6, 0xf7537e82);
 215         OP (FI, D, A, B, C, 11, 10, 0xbd3af235);
 216         OP (FI, C, D, A, B,  2, 15, 0x2ad7d2bb);
 217         OP (FI, B, C, D, A,  9, 21, 0xeb86d391);
 218
 219         /* Put checksum in context given as argument.  */
 220         ctx->A += A;
 221         ctx->B += B;
 222         ctx->C += C;
 223         ctx->D += D;
 224 }
 225
 226
 227
 228 /* The routine updates the message-digest context to
 229  * account for the presence of each of the characters inBuf[0..inLen-1]
 230  * in the message whose digest is being computed.
 231  */
 232 static void
 233 md5_update(MD5_CONTEXT *hd, const unsigned char *inbuf, size_t inlen)
 234 {
 235         if (hd->count == 64) { /* flush the buffer */
 236                 transform( hd, hd->buf );
 237                 hd->count = 0;
 238                 hd->nblocks++;
 239         }
 240         if (!inbuf)
 241                 return;
 242         if (hd->count) {
 243                 for (; inlen && hd->count < 64; inlen--)
 244                         hd->buf[hd->count++] = *inbuf++;
 245                 md5_update(hd, NULL, 0);
 246                 if (!inlen)
 247                         return;
 248         }
 249
 250         while (inlen >= 64) {
 251                 transform(hd, inbuf);
 252                 hd->count = 0;
 253                 hd->nblocks++;
 254                 inlen -= 64;
 255                 inbuf += 64;
 256         }
 257
 258         for (; inlen && hd->count < 64; inlen--)
 259                 hd->buf[hd->count++] = *inbuf++;
 260 }
 261
 262
 263
 264 /* The routine final terminates the message-digest computation and
 265  * ends with the desired message digest in mdContext->digest[0...15].
 266  * The handle is prepared for a new MD5 cycle.
 267  * Returns 16 bytes representing the digest.
 268  */
 269
 270 static void
 271 do_final(MD5_CONTEXT *hd)
 272 {
 273         guint32 t, msb, lsb;
 274         unsigned char *p;
 275
 276         md5_update(hd, NULL, 0); /* flush */
 277
 278         msb = 0;
 279         t = hd->nblocks;
 280         if ((lsb = t << 6) < t) /* multiply by 64 to make a byte count */
 281                 msb++;
 282         msb += t >> 26;
 283         t = lsb;
 284         if ((lsb = t + hd->count) < t) /* add the count */
 285                 msb++;
 286         t = lsb;
 287         if ((lsb = t << 3) < t) /* multiply by 8 to make a bit count */
 288                 msb++;
 289         msb += t >> 29;
 290
 291         if (hd->count < 56) { /* enough room */
 292                 hd->buf[hd->count++] = 0x80; /* pad */
 293                 while(hd->count < 56)
 294                         hd->buf[hd->count++] = 0;  /* pad */
 295         } else { /* need one extra block */
 296                 hd->buf[hd->count++] = 0x80; /* pad character */
 297                 while (hd->count < 64)
 298                         hd->buf[hd->count++] = 0;
 299                 md5_update(hd, NULL, 0);  /* flush */
 300                 memset(hd->buf, 0, 56); /* fill next block with zeroes */
 301         }
 302
 303         /* append the 64 bit count */
 304         hd->buf[56] = lsb      ;
 305         hd->buf[57] = lsb >>  8;
 306         hd->buf[58] = lsb >> 16;
 307         hd->buf[59] = lsb >> 24;
 308         hd->buf[60] = msb      ;
 309         hd->buf[61] = msb >>  8;
 310         hd->buf[62] = msb >> 16;
 311         hd->buf[63] = msb >> 24;
 312         transform(hd, hd->buf);
 313
 314         p = hd->buf;
 315 #ifdef BIG_ENDIAN_HOST
 316 #define X(a) do { *p++ = hd->a      ; *p++ = hd->a >> 8;      \
 317                   *p++ = hd->a >> 16; *p++ = hd->a >> 24; } while(0)
 318 #else /* little endian */
 319         /*#define X(a) do { *(guint32*)p = hd->##a ; p += 4; } while(0)*/
 320         /* Unixware's cpp doesn't like the above construct so we do it his way:
 321          * (reported by Allan Clark) */
 322 #define X(a) do { *(guint32*)p = (*hd).a ; p += 4; } while(0)
 323 #endif
 324         X(A);
 325         X(B);
 326         X(C);
 327         X(D);
 328 #undef X
 329         hd->finalized = 1;
 330 }
 331
 332 static void
 333 md5_final(unsigned char *digest, MD5_CONTEXT *ctx)
 334 {
 335         if (!ctx->finalized)
 336                 do_final(ctx);
 337         memcpy(digest, ctx->buf, 16);
 338 }
 339
 340 /*
 341  * Creates a MD5 digest in hex fomrat (lowercase letters) from the
 342  * string S.  hextdigest but be buffer of at lease 33 bytes!
 343  */
 344 static void
 345 md5_hex_digest_binary(char *hexdigest, const unsigned char *s, size_t len)
 346 {
 347         int i;
 348         MD5_CONTEXT context;
 349         unsigned char digest[16];
 350
 351         md5_init(&context);
 352         md5_update(&context, s, len);
 353         md5_final(digest, &context);
 354
 355         for (i = 0; i < 16; i++)
 356                 sprintf(hexdigest + 2 * i, "%02x", digest[i]);
 357 }
 358
 359 int
 360 md5_hex_digest_file(char *hexdigest, const unsigned char *file)
 361 {
 362         int READ_BLOCK_SIZE=4096;
 363         int len;
 364         char *buf = malloc(READ_BLOCK_SIZE); /* alloc the first block */
 365         char *lastp = buf; /* point to the start of the buffer */
 366         size_t total = 0; /* total length read */
 367         int num_alloc = 1; /* number of blocks allocated */
 368         int fd = g_open(file, O_RDONLY, 0);
 369
 370         if (fd == -1) {
 371                 FILE_OP_ERROR(file, "open");
 372                 free(buf);
 373                 return -1;
 374         }
 375
 376         while ((len = read(fd, lastp, READ_BLOCK_SIZE)) > 0) { /* read one block (which is allocated) */
 377                 total += len; /* update the total length */
 378                 num_alloc++; /* increase number of allocs */
 379                 buf = realloc(buf, READ_BLOCK_SIZE*num_alloc); /* allocate one more block for next read */
 380                 lastp = buf+total; /* point to the end of read stuff to buf */
 381         }
 382
 383         close(fd);
 384         md5_hex_digest_binary(hexdigest, buf, total);
 385         free(buf);
 386         // printf("%s  %s\n", hexdigest, file);
 387         return 0;
 388 }
 389
 390 /*
 391  * Creates a MD5 digest in hex fomrat (lowercase letters) from the
 392  * string S.  hextdigest but be buffer of at lease 33 bytes!
 393  */
 394 void
 395 md5_hex_digest(char *hexdigest, const unsigned char *s)
 396 {
 397         g_return_if_fail(hexdigest != NULL);
 398         g_return_if_fail(s != NULL);
 399         md5_hex_digest_binary(hexdigest, s, strlen(s));
 400 }
 401
 402 /*
 403 ** Function: md5_hmac
 404 ** taken from the file rfc2104.txt
 405 ** written by Martin Schaaf <mascha@ma-scha.de>
 406 */
 407 static void
 408 md5_hmac(unsigned char *digest,
 409          const unsigned char* text, int text_len,
 410          const unsigned char* key, int key_len)
 411 {
 412         MD5_CONTEXT context;
 413         unsigned char k_ipad[64];    /* inner padding -
 414                                       * key XORd with ipad
 415                                       */
 416         unsigned char k_opad[64];    /* outer padding -
 417                                       * key XORd with opad
 418                                       */
 419         /* unsigned char tk[16]; */
 420         int i;
 421
 422         /* start out by storing key in pads */
 423         memset(k_ipad, 0, sizeof k_ipad);
 424         memset(k_opad, 0, sizeof k_opad);
 425         if (key_len > 64) {
 426                 /* if key is longer than 64 bytes reset it to key=MD5(key) */
 427                 MD5_CONTEXT tctx;
 428
 429                 md5_init(&tctx);
 430                 md5_update(&tctx, key, key_len);
 431                 md5_final(k_ipad, &tctx);
 432                 md5_final(k_opad, &tctx);
 433         } else {
 434                 memcpy(k_ipad, key, key_len);
 435                 memcpy(k_opad, key, key_len);
 436         }
 437
 438         /*
 439          * the HMAC_MD5 transform looks like:
 440          *
 441          * MD5(K XOR opad, MD5(K XOR ipad, text))
 442          *
 443          * where K is an n byte key
 444          * ipad is the byte 0x36 repeated 64 times
 445          * opad is the byte 0x5c repeated 64 times
 446          * and text is the data being protected
 447          */
 448
 449
 450         /* XOR key with ipad and opad values */
 451         for (i = 0; i < 64; i++) {
 452                 k_ipad[i] ^= 0x36;
 453                 k_opad[i] ^= 0x5c;
 454         }
 455
 456         /*
 457          * perform inner MD5
 458          */
 459         md5_init(&context);                   /* init context for 1st
 460                                                * pass */
 461         md5_update(&context, k_ipad, 64);     /* start with inner pad */
 462         md5_update(&context, text, text_len); /* then text of datagram */
 463         md5_final(digest, &context);          /* finish up 1st pass */
 464         /*
 465          * perform outer MD5
 466          */
 467         md5_init(&context);                   /* init context for 2nd
 468                                                * pass */
 469         md5_update(&context, k_opad, 64);     /* start with outer pad */
 470         md5_update(&context, digest, 16);     /* then results of 1st
 471                                                * hash */
 472         md5_final(digest, &context);          /* finish up 2nd pass */
 473 }
 474
 475
 476 void
 477 md5_hex_hmac(char *hexdigest,
 478              const unsigned char* text, int text_len,
 479              const unsigned char* key, int key_len)
 480 {
 481         unsigned char digest[16];
 482         int i;
 483
 484         g_return_if_fail(key != NULL);
 485         g_return_if_fail(key_len >= 0);
 486         g_return_if_fail(text != NULL);
 487         g_return_if_fail(text_len >= 0);
 488         g_return_if_fail(hexdigest != NULL);
 489
 490         md5_hmac(digest, text, text_len, key, key_len);
 491         for (i = 0; i < 16; i++)
 492                 sprintf(hexdigest + 2 * i, "%02x", digest[i]);
 493 }