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 "md5.h"
  57
  58 /*
  59  * The basic MD5 functions.
  60  *
  61  * F and G are optimized compared to their RFC 1321 definitions for
  62  * architectures that lack an AND-NOT instruction, just like in Colin Plumb's
  63  * implementation.
  64  */
  65 #define F(x, y, z)                      ((z) ^ ((x) & ((y) ^ (z))))
  66 #define G(x, y, z)                      ((y) ^ ((z) & ((x) ^ (y))))
  67 #define H(x, y, z)                      (((x) ^ (y)) ^ (z))
  68 #define H2(x, y, z)                     ((x) ^ ((y) ^ (z)))
  69 #define I(x, y, z)                      ((y) ^ ((x) | ~(z)))
  70
  71 /*
  72  * The MD5 transformation for all four rounds.
  73  */
  74 #define STEP(f, a, b, c, d, x, t, s) \
  75         (a) += f((b), (c), (d)) + (x) + (t); \
  76         (a) = (((a) << (s)) | (((a) & 0xffffffff) >> (32 - (s)))); \
  77         (a) += (b);
  78
  79 /*
  80  * SET reads 4 input bytes in little-endian byte order and stores them
  81  * in a properly aligned word in host byte order.
  82  */
  83 #if __BYTE_ORDER == __LITTLE_ENDIAN
  84 #define SET(n) \
  85         (*(uint32_t *)&ptr[(n) * 4])
  86 #define GET(n) \
  87         SET(n)
  88 #else
  89 #define SET(n) \
  90         (block[(n)] = \
  91         (uint32_t)ptr[(n) * 4] | \
  92         ((uint32_t)ptr[(n) * 4 + 1] << 8) | \
  93         ((uint32_t)ptr[(n) * 4 + 2] << 16) | \
  94         ((uint32_t)ptr[(n) * 4 + 3] << 24))
  95 #define GET(n) \
  96         (block[(n)])
  97 #endif
  98
  99 /*
 100  * This processes one or more 64-byte data blocks, but does NOT update
 101  * the bit counters.  There are no alignment requirements.
 102  */
 103 static const void *body(md5_ctx_t *ctx, const void *data, unsigned long size)
 104 {
 105         const unsigned char *ptr;
 106         uint32_t a, b, c, d;
 107         uint32_t saved_a, saved_b, saved_c, saved_d;
 108 #if __BYTE_ORDER != __LITTLE_ENDIAN
 109         uint32_t block[16];
 110 #endif
 111
 112         ptr = (const unsigned char *)data;
 113
 114         a = ctx->a;
 115         b = ctx->b;
 116         c = ctx->c;
 117         d = ctx->d;
 118
 119         do {
 120                 saved_a = a;
 121                 saved_b = b;
 122                 saved_c = c;
 123                 saved_d = d;
 124
 125 /* Round 1 */
 126                 STEP(F, a, b, c, d, SET(0), 0xd76aa478, 7)
 127                 STEP(F, d, a, b, c, SET(1), 0xe8c7b756, 12)
 128                 STEP(F, c, d, a, b, SET(2), 0x242070db, 17)
 129                 STEP(F, b, c, d, a, SET(3), 0xc1bdceee, 22)
 130                 STEP(F, a, b, c, d, SET(4), 0xf57c0faf, 7)
 131                 STEP(F, d, a, b, c, SET(5), 0x4787c62a, 12)
 132                 STEP(F, c, d, a, b, SET(6), 0xa8304613, 17)
 133                 STEP(F, b, c, d, a, SET(7), 0xfd469501, 22)
 134                 STEP(F, a, b, c, d, SET(8), 0x698098d8, 7)
 135                 STEP(F, d, a, b, c, SET(9), 0x8b44f7af, 12)
 136                 STEP(F, c, d, a, b, SET(10), 0xffff5bb1, 17)
 137                 STEP(F, b, c, d, a, SET(11), 0x895cd7be, 22)
 138                 STEP(F, a, b, c, d, SET(12), 0x6b901122, 7)
 139                 STEP(F, d, a, b, c, SET(13), 0xfd987193, 12)
 140                 STEP(F, c, d, a, b, SET(14), 0xa679438e, 17)
 141                 STEP(F, b, c, d, a, SET(15), 0x49b40821, 22)
 142
 143 /* Round 2 */
 144                 STEP(G, a, b, c, d, GET(1), 0xf61e2562, 5)
 145                 STEP(G, d, a, b, c, GET(6), 0xc040b340, 9)
 146                 STEP(G, c, d, a, b, GET(11), 0x265e5a51, 14)
 147                 STEP(G, b, c, d, a, GET(0), 0xe9b6c7aa, 20)
 148                 STEP(G, a, b, c, d, GET(5), 0xd62f105d, 5)
 149                 STEP(G, d, a, b, c, GET(10), 0x02441453, 9)
 150                 STEP(G, c, d, a, b, GET(15), 0xd8a1e681, 14)
 151                 STEP(G, b, c, d, a, GET(4), 0xe7d3fbc8, 20)
 152                 STEP(G, a, b, c, d, GET(9), 0x21e1cde6, 5)
 153                 STEP(G, d, a, b, c, GET(14), 0xc33707d6, 9)
 154                 STEP(G, c, d, a, b, GET(3), 0xf4d50d87, 14)
 155                 STEP(G, b, c, d, a, GET(8), 0x455a14ed, 20)
 156                 STEP(G, a, b, c, d, GET(13), 0xa9e3e905, 5)
 157                 STEP(G, d, a, b, c, GET(2), 0xfcefa3f8, 9)
 158                 STEP(G, c, d, a, b, GET(7), 0x676f02d9, 14)
 159                 STEP(G, b, c, d, a, GET(12), 0x8d2a4c8a, 20)
 160
 161 /* Round 3 */
 162                 STEP(H, a, b, c, d, GET(5), 0xfffa3942, 4)
 163                 STEP(H2, d, a, b, c, GET(8), 0x8771f681, 11)
 164                 STEP(H, c, d, a, b, GET(11), 0x6d9d6122, 16)
 165                 STEP(H2, b, c, d, a, GET(14), 0xfde5380c, 23)
 166                 STEP(H, a, b, c, d, GET(1), 0xa4beea44, 4)
 167                 STEP(H2, d, a, b, c, GET(4), 0x4bdecfa9, 11)
 168                 STEP(H, c, d, a, b, GET(7), 0xf6bb4b60, 16)
 169                 STEP(H2, b, c, d, a, GET(10), 0xbebfbc70, 23)
 170                 STEP(H, a, b, c, d, GET(13), 0x289b7ec6, 4)
 171                 STEP(H2, d, a, b, c, GET(0), 0xeaa127fa, 11)
 172                 STEP(H, c, d, a, b, GET(3), 0xd4ef3085, 16)
 173                 STEP(H2, b, c, d, a, GET(6), 0x04881d05, 23)
 174                 STEP(H, a, b, c, d, GET(9), 0xd9d4d039, 4)
 175                 STEP(H2, d, a, b, c, GET(12), 0xe6db99e5, 11)
 176                 STEP(H, c, d, a, b, GET(15), 0x1fa27cf8, 16)
 177                 STEP(H2, b, c, d, a, GET(2), 0xc4ac5665, 23)
 178
 179 /* Round 4 */
 180                 STEP(I, a, b, c, d, GET(0), 0xf4292244, 6)
 181                 STEP(I, d, a, b, c, GET(7), 0x432aff97, 10)
 182                 STEP(I, c, d, a, b, GET(14), 0xab9423a7, 15)
 183                 STEP(I, b, c, d, a, GET(5), 0xfc93a039, 21)
 184                 STEP(I, a, b, c, d, GET(12), 0x655b59c3, 6)
 185                 STEP(I, d, a, b, c, GET(3), 0x8f0ccc92, 10)
 186                 STEP(I, c, d, a, b, GET(10), 0xffeff47d, 15)
 187                 STEP(I, b, c, d, a, GET(1), 0x85845dd1, 21)
 188                 STEP(I, a, b, c, d, GET(8), 0x6fa87e4f, 6)
 189                 STEP(I, d, a, b, c, GET(15), 0xfe2ce6e0, 10)
 190                 STEP(I, c, d, a, b, GET(6), 0xa3014314, 15)
 191                 STEP(I, b, c, d, a, GET(13), 0x4e0811a1, 21)
 192                 STEP(I, a, b, c, d, GET(4), 0xf7537e82, 6)
 193                 STEP(I, d, a, b, c, GET(11), 0xbd3af235, 10)
 194                 STEP(I, c, d, a, b, GET(2), 0x2ad7d2bb, 15)
 195                 STEP(I, b, c, d, a, GET(9), 0xeb86d391, 21)
 196
 197                 a += saved_a;
 198                 b += saved_b;
 199                 c += saved_c;
 200                 d += saved_d;
 201
 202                 ptr += 64;
 203         } while (size -= 64);
 204
 205         ctx->a = a;
 206         ctx->b = b;
 207         ctx->c = c;
 208         ctx->d = d;
 209
 210         return ptr;
 211 }
 212
 213 void md5_begin(md5_ctx_t *ctx)
 214 {
 215         ctx->a = 0x67452301;
 216         ctx->b = 0xefcdab89;
 217         ctx->c = 0x98badcfe;
 218         ctx->d = 0x10325476;
 219
 220         ctx->lo = 0;
 221         ctx->hi = 0;
 222 }
 223
 224 void md5_hash(const void *data, size_t size, md5_ctx_t *ctx)
 225 {
 226         uint32_t saved_lo;
 227         unsigned long used, available;
 228
 229         saved_lo = ctx->lo;
 230         if ((ctx->lo = (saved_lo + size) & 0x1fffffff) < saved_lo)
 231                 ctx->hi++;
 232         ctx->hi += size >> 29;
 233
 234         used = saved_lo & 0x3f;
 235
 236         if (used) {
 237                 available = 64 - used;
 238
 239                 if (size < available) {
 240                         memcpy(&ctx->buffer[used], data, size);
 241                         return;
 242                 }
 243
 244                 memcpy(&ctx->buffer[used], data, available);
 245                 data = (const unsigned char *)data + available;
 246                 size -= available;
 247                 body(ctx, ctx->buffer, 64);
 248         }
 249
 250         if (size >= 64) {
 251                 data = body(ctx, data, size & ~((size_t) 0x3f));
 252                 size &= 0x3f;
 253         }
 254
 255         memcpy(ctx->buffer, data, size);
 256 }
 257
 258 void md5_end(void *resbuf, md5_ctx_t *ctx)
 259 {
 260         unsigned char *result = resbuf;
 261         unsigned long used, available;
 262
 263         used = ctx->lo & 0x3f;
 264
 265         ctx->buffer[used++] = 0x80;
 266
 267         available = 64 - used;
 268
 269         if (available < 8) {
 270                 memset(&ctx->buffer[used], 0, available);
 271                 body(ctx, ctx->buffer, 64);
 272                 used = 0;
 273                 available = 64;
 274         }
 275
 276         memset(&ctx->buffer[used], 0, available - 8);
 277
 278         ctx->lo <<= 3;
 279         ctx->buffer[56] = ctx->lo;
 280         ctx->buffer[57] = ctx->lo >> 8;
 281         ctx->buffer[58] = ctx->lo >> 16;
 282         ctx->buffer[59] = ctx->lo >> 24;
 283         ctx->buffer[60] = ctx->hi;
 284         ctx->buffer[61] = ctx->hi >> 8;
 285         ctx->buffer[62] = ctx->hi >> 16;
 286         ctx->buffer[63] = ctx->hi >> 24;
 287
 288         body(ctx, ctx->buffer, 64);
 289
 290         result[0] = ctx->a;
 291         result[1] = ctx->a >> 8;
 292         result[2] = ctx->a >> 16;
 293         result[3] = ctx->a >> 24;
 294         result[4] = ctx->b;
 295         result[5] = ctx->b >> 8;
 296         result[6] = ctx->b >> 16;
 297         result[7] = ctx->b >> 24;
 298         result[8] = ctx->c;
 299         result[9] = ctx->c >> 8;
 300         result[10] = ctx->c >> 16;
 301         result[11] = ctx->c >> 24;
 302         result[12] = ctx->d;
 303         result[13] = ctx->d >> 8;
 304         result[14] = ctx->d >> 16;
 305         result[15] = ctx->d >> 24;
 306
 307         memset(ctx, 0, sizeof(*ctx));
 308 }
 309
 310 int md5sum(char *file, void *md5_buf)
 311 {
 312         char buf[256];
 313         md5_ctx_t ctx;
 314         int ret = 0;
 315         FILE *f;
 316
 317         f = fopen(file, "r");
 318         if (!f)
 319                 return -1;
 320
 321         md5_begin(&ctx);
 322         do {
 323                 int len = fread(buf, 1, sizeof(buf), f);
 324                 if (!len)
 325                         break;
 326
 327                 md5_hash(buf, len, &ctx);
 328                 ret += len;
 329         } while(1);
 330
 331         md5_end(md5_buf, &ctx);
 332         fclose(f);
 333
 334         return ret;
 335 }