md5.c

   1 /*
   2  * Copyright (C) 2014 Felix Fietkau <nbd@openwrt.org>
   3  *
   4  * Permission to use, copy, modify, and/or distribute this software for any
   5  * purpose with or without fee is hereby granted, provided that the above
   6  * copyright notice and this permission notice appear in all copies.
   7  *
   8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  15  */
  16 /*
  17  * This is an OpenSSL-compatible implementation of the RSA Data Security, Inc.
  18  * MD5 Message-Digest Algorithm (RFC 1321).
  19  *
  20  * Homepage:
  21  * http://openwall.info/wiki/people/solar/software/public-domain-source-code/md5
  22  *
  23  * Author:
  24  * Alexander Peslyak, better known as Solar Designer <solar at openwall.com>
  25  *
  26  * This software was written by Alexander Peslyak in 2001.  No copyright is
  27  * claimed, and the software is hereby placed in the public domain.
  28  * In case this attempt to disclaim copyright and place the software in the
  29  * public domain is deemed null and void, then the software is
  30  * Copyright (c) 2001 Alexander Peslyak and it is hereby released to the
  31  * general public under the following terms:
  32  *
  33  * Redistribution and use in source and binary forms, with or without
  34  * modification, are permitted.
  35  *
  36  * There's ABSOLUTELY NO WARRANTY, express or implied.
  37  *
  38  * (This is a heavily cut-down "BSD license".)
  39  *
  40  * This differs from Colin Plumb's older public domain implementation in that
  41  * no exactly 32-bit integer data type is required (any 32-bit or wider
  42  * unsigned integer data type will do), there's no compile-time endianness
  43  * configuration, and the function prototypes match OpenSSL's.  No code from
  44  * Colin Plumb's implementation has been reused; this comment merely compares
  45  * the properties of the two independent implementations.
  46  *
  47  * The primary goals of this implementation are portability and ease of use.
  48  * It is meant to be fast, but not as fast as possible.  Some known
  49  * optimizations are not included to reduce source code size and avoid
  50  * compile-time configuration.
  51  */
  52
  53 #include <string.h>
  54 #include <stdio.h>
  55
  56 #include "utils.h"
  57 #include "md5.h"
  58
  59 /*
  60  * The basic MD5 functions.
  61  *
  62  * F and G are optimized compared to their RFC 1321 definitions for
  63  * architectures that lack an AND-NOT instruction, just like in Colin Plumb's
  64  * implementation.
  65  */
  66 #define F(x, y, z)                      ((z) ^ ((x) & ((y) ^ (z))))
  67 #define G(x, y, z)                      ((y) ^ ((z) & ((x) ^ (y))))
  68 #define H(x, y, z)                      (((x) ^ (y)) ^ (z))
  69 #define H2(x, y, z)                     ((x) ^ ((y) ^ (z)))
  70 #define I(x, y, z)                      ((y) ^ ((x) | ~(z)))
  71
  72 /*
  73  * The MD5 transformation for all four rounds.
  74  */
  75 #define STEP(f, a, b, c, d, x, t, s) \
  76         (a) += f((b), (c), (d)) + (x) + (t); \
  77         (a) = (((a) << (s)) | (((a) & 0xffffffff) >> (32 - (s)))); \
  78         (a) += (b);
  79
  80 /*
  81  * SET reads 4 input bytes in little-endian byte order and stores them
  82  * in a properly aligned word in host byte order.
  83  */
  84 #if __BYTE_ORDER == __LITTLE_ENDIAN
  85 #define SET(n) \
  86         (*(uint32_t *)&ptr[(n) * 4])
  87 #define GET(n) \
  88         SET(n)
  89 #else
  90 #define SET(n) \
  91         (block[(n)] = \
  92         (uint32_t)ptr[(n) * 4] | \
  93         ((uint32_t)ptr[(n) * 4 + 1] << 8) | \
  94         ((uint32_t)ptr[(n) * 4 + 2] << 16) | \
  95         ((uint32_t)ptr[(n) * 4 + 3] << 24))
  96 #define GET(n) \
  97         (block[(n)])
  98 #endif
  99
 100 /*
 101  * This processes one or more 64-byte data blocks, but does NOT update
 102  * the bit counters.  There are no alignment requirements.
 103  */
 104 static const void *body(md5_ctx_t *ctx, const void *data, unsigned long size)
 105 {
 106         const unsigned char *ptr;
 107         uint32_t a, b, c, d;
 108         uint32_t saved_a, saved_b, saved_c, saved_d;
 109 #if __BYTE_ORDER != __LITTLE_ENDIAN
 110         uint32_t block[16];
 111 #endif
 112
 113         ptr = (const unsigned char *)data;
 114
 115         a = ctx->a;
 116         b = ctx->b;
 117         c = ctx->c;
 118         d = ctx->d;
 119
 120         do {
 121                 saved_a = a;
 122                 saved_b = b;
 123                 saved_c = c;
 124                 saved_d = d;
 125
 126 /* Round 1 */
 127                 STEP(F, a, b, c, d, SET(0), 0xd76aa478, 7)
 128                 STEP(F, d, a, b, c, SET(1), 0xe8c7b756, 12)
 129                 STEP(F, c, d, a, b, SET(2), 0x242070db, 17)
 130                 STEP(F, b, c, d, a, SET(3), 0xc1bdceee, 22)
 131                 STEP(F, a, b, c, d, SET(4), 0xf57c0faf, 7)
 132                 STEP(F, d, a, b, c, SET(5), 0x4787c62a, 12)
 133                 STEP(F, c, d, a, b, SET(6), 0xa8304613, 17)
 134                 STEP(F, b, c, d, a, SET(7), 0xfd469501, 22)
 135                 STEP(F, a, b, c, d, SET(8), 0x698098d8, 7)
 136                 STEP(F, d, a, b, c, SET(9), 0x8b44f7af, 12)
 137                 STEP(F, c, d, a, b, SET(10), 0xffff5bb1, 17)
 138                 STEP(F, b, c, d, a, SET(11), 0x895cd7be, 22)
 139                 STEP(F, a, b, c, d, SET(12), 0x6b901122, 7)
 140                 STEP(F, d, a, b, c, SET(13), 0xfd987193, 12)
 141                 STEP(F, c, d, a, b, SET(14), 0xa679438e, 17)
 142                 STEP(F, b, c, d, a, SET(15), 0x49b40821, 22)
 143
 144 /* Round 2 */
 145                 STEP(G, a, b, c, d, GET(1), 0xf61e2562, 5)
 146                 STEP(G, d, a, b, c, GET(6), 0xc040b340, 9)
 147                 STEP(G, c, d, a, b, GET(11), 0x265e5a51, 14)
 148                 STEP(G, b, c, d, a, GET(0), 0xe9b6c7aa, 20)
 149                 STEP(G, a, b, c, d, GET(5), 0xd62f105d, 5)
 150                 STEP(G, d, a, b, c, GET(10), 0x02441453, 9)
 151                 STEP(G, c, d, a, b, GET(15), 0xd8a1e681, 14)
 152                 STEP(G, b, c, d, a, GET(4), 0xe7d3fbc8, 20)
 153                 STEP(G, a, b, c, d, GET(9), 0x21e1cde6, 5)
 154                 STEP(G, d, a, b, c, GET(14), 0xc33707d6, 9)
 155                 STEP(G, c, d, a, b, GET(3), 0xf4d50d87, 14)
 156                 STEP(G, b, c, d, a, GET(8), 0x455a14ed, 20)
 157                 STEP(G, a, b, c, d, GET(13), 0xa9e3e905, 5)
 158                 STEP(G, d, a, b, c, GET(2), 0xfcefa3f8, 9)
 159                 STEP(G, c, d, a, b, GET(7), 0x676f02d9, 14)
 160                 STEP(G, b, c, d, a, GET(12), 0x8d2a4c8a, 20)
 161
 162 /* Round 3 */
 163                 STEP(H, a, b, c, d, GET(5), 0xfffa3942, 4)
 164                 STEP(H2, d, a, b, c, GET(8), 0x8771f681, 11)
 165                 STEP(H, c, d, a, b, GET(11), 0x6d9d6122, 16)
 166                 STEP(H2, b, c, d, a, GET(14), 0xfde5380c, 23)
 167                 STEP(H, a, b, c, d, GET(1), 0xa4beea44, 4)
 168                 STEP(H2, d, a, b, c, GET(4), 0x4bdecfa9, 11)
 169                 STEP(H, c, d, a, b, GET(7), 0xf6bb4b60, 16)
 170                 STEP(H2, b, c, d, a, GET(10), 0xbebfbc70, 23)
 171                 STEP(H, a, b, c, d, GET(13), 0x289b7ec6, 4)
 172                 STEP(H2, d, a, b, c, GET(0), 0xeaa127fa, 11)
 173                 STEP(H, c, d, a, b, GET(3), 0xd4ef3085, 16)
 174                 STEP(H2, b, c, d, a, GET(6), 0x04881d05, 23)
 175                 STEP(H, a, b, c, d, GET(9), 0xd9d4d039, 4)
 176                 STEP(H2, d, a, b, c, GET(12), 0xe6db99e5, 11)
 177                 STEP(H, c, d, a, b, GET(15), 0x1fa27cf8, 16)
 178                 STEP(H2, b, c, d, a, GET(2), 0xc4ac5665, 23)
 179
 180 /* Round 4 */
 181                 STEP(I, a, b, c, d, GET(0), 0xf4292244, 6)
 182                 STEP(I, d, a, b, c, GET(7), 0x432aff97, 10)
 183                 STEP(I, c, d, a, b, GET(14), 0xab9423a7, 15)
 184                 STEP(I, b, c, d, a, GET(5), 0xfc93a039, 21)
 185                 STEP(I, a, b, c, d, GET(12), 0x655b59c3, 6)
 186                 STEP(I, d, a, b, c, GET(3), 0x8f0ccc92, 10)
 187                 STEP(I, c, d, a, b, GET(10), 0xffeff47d, 15)
 188                 STEP(I, b, c, d, a, GET(1), 0x85845dd1, 21)
 189                 STEP(I, a, b, c, d, GET(8), 0x6fa87e4f, 6)
 190                 STEP(I, d, a, b, c, GET(15), 0xfe2ce6e0, 10)
 191                 STEP(I, c, d, a, b, GET(6), 0xa3014314, 15)
 192                 STEP(I, b, c, d, a, GET(13), 0x4e0811a1, 21)
 193                 STEP(I, a, b, c, d, GET(4), 0xf7537e82, 6)
 194                 STEP(I, d, a, b, c, GET(11), 0xbd3af235, 10)
 195                 STEP(I, c, d, a, b, GET(2), 0x2ad7d2bb, 15)
 196                 STEP(I, b, c, d, a, GET(9), 0xeb86d391, 21)
 197
 198                 a += saved_a;
 199                 b += saved_b;
 200                 c += saved_c;
 201                 d += saved_d;
 202
 203                 ptr += 64;
 204         } while (size -= 64);
 205
 206         ctx->a = a;
 207         ctx->b = b;
 208         ctx->c = c;
 209         ctx->d = d;
 210
 211         return ptr;
 212 }
 213
 214 void md5_begin(md5_ctx_t *ctx)
 215 {
 216         ctx->a = 0x67452301;
 217         ctx->b = 0xefcdab89;
 218         ctx->c = 0x98badcfe;
 219         ctx->d = 0x10325476;
 220
 221         ctx->lo = 0;
 222         ctx->hi = 0;
 223 }
 224
 225 void md5_hash(const void *data, size_t size, md5_ctx_t *ctx)
 226 {
 227         uint32_t saved_lo;
 228         unsigned long used, available;
 229
 230         saved_lo = ctx->lo;
 231         if ((ctx->lo = (saved_lo + size) & 0x1fffffff) < saved_lo)
 232                 ctx->hi++;
 233         ctx->hi += size >> 29;
 234
 235         used = saved_lo & 0x3f;
 236
 237         if (used) {
 238                 available = 64 - used;
 239
 240                 if (size < available) {
 241                         memcpy(&ctx->buffer[used], data, size);
 242                         return;
 243                 }
 244
 245                 memcpy(&ctx->buffer[used], data, available);
 246                 data = (const unsigned char *)data + available;
 247                 size -= available;
 248                 body(ctx, ctx->buffer, 64);
 249         }
 250
 251         if (size >= 64) {
 252                 data = body(ctx, data, size & ~((size_t) 0x3f));
 253                 size &= 0x3f;
 254         }
 255
 256         memcpy(ctx->buffer, data, size);
 257 }
 258
 259 void md5_end(void *resbuf, md5_ctx_t *ctx)
 260 {
 261         unsigned char *result = resbuf;
 262         unsigned long used, available;
 263
 264         used = ctx->lo & 0x3f;
 265
 266         ctx->buffer[used++] = 0x80;
 267
 268         available = 64 - used;
 269
 270         if (available < 8) {
 271                 memset(&ctx->buffer[used], 0, available);
 272                 body(ctx, ctx->buffer, 64);
 273                 used = 0;
 274                 available = 64;
 275         }
 276
 277         memset(&ctx->buffer[used], 0, available - 8);
 278
 279         ctx->lo <<= 3;
 280         ctx->buffer[56] = ctx->lo;
 281         ctx->buffer[57] = ctx->lo >> 8;
 282         ctx->buffer[58] = ctx->lo >> 16;
 283         ctx->buffer[59] = ctx->lo >> 24;
 284         ctx->buffer[60] = ctx->hi;
 285         ctx->buffer[61] = ctx->hi >> 8;
 286         ctx->buffer[62] = ctx->hi >> 16;
 287         ctx->buffer[63] = ctx->hi >> 24;
 288
 289         body(ctx, ctx->buffer, 64);
 290
 291         result[0] = ctx->a;
 292         result[1] = ctx->a >> 8;
 293         result[2] = ctx->a >> 16;
 294         result[3] = ctx->a >> 24;
 295         result[4] = ctx->b;
 296         result[5] = ctx->b >> 8;
 297         result[6] = ctx->b >> 16;
 298         result[7] = ctx->b >> 24;
 299         result[8] = ctx->c;
 300         result[9] = ctx->c >> 8;
 301         result[10] = ctx->c >> 16;
 302         result[11] = ctx->c >> 24;
 303         result[12] = ctx->d;
 304         result[13] = ctx->d >> 8;
 305         result[14] = ctx->d >> 16;
 306         result[15] = ctx->d >> 24;
 307
 308         memset(ctx, 0, sizeof(*ctx));
 309 }
 310
 311 int md5sum(char *file, void *md5_buf)
 312 {
 313         char buf[256];
 314         md5_ctx_t ctx;
 315         int ret = 0;
 316         FILE *f;
 317
 318         f = fopen(file, "r");
 319         if (!f)
 320                 return -1;
 321
 322         md5_begin(&ctx);
 323         do {
 324                 int len = fread(buf, 1, sizeof(buf), f);
 325                 if (!len)
 326                         break;
 327
 328                 md5_hash(buf, len, &ctx);
 329                 ret += len;
 330         } while(1);
 331
 332         md5_end(md5_buf, &ctx);
 333         fclose(f);
 334
 335         return ret;
 336 }