/Modules/md5.c
C | 394 lines | 270 code | 27 blank | 97 comment | 17 complexity | cde8744da846bbcd348a5126acb9f7b0 MD5 | raw file
1/* 2 Copyright (C) 1999, 2000, 2002 Aladdin Enterprises. All rights reserved. 3 4 This software is provided 'as-is', without any express or implied 5 warranty. In no event will the authors be held liable for any damages 6 arising from the use of this software. 7 8 Permission is granted to anyone to use this software for any purpose, 9 including commercial applications, and to alter it and redistribute it 10 freely, subject to the following restrictions: 11 12 1. The origin of this software must not be misrepresented; you must not 13 claim that you wrote the original software. If you use this software 14 in a product, an acknowledgment in the product documentation would be 15 appreciated but is not required. 16 2. Altered source versions must be plainly marked as such, and must not be 17 misrepresented as being the original software. 18 3. This notice may not be removed or altered from any source distribution. 19 20 L. Peter Deutsch 21 ghost@aladdin.com 22 23 */ 24/* $Id: md5.c,v 1.6 2002/04/13 19:20:28 lpd Exp $ */ 25/* 26 Independent implementation of MD5 (RFC 1321). 27 28 This code implements the MD5 Algorithm defined in RFC 1321, whose 29 text is available at 30 http://www.ietf.org/rfc/rfc1321.txt 31 The code is derived from the text of the RFC, including the test suite 32 (section A.5) but excluding the rest of Appendix A. It does not include 33 any code or documentation that is identified in the RFC as being 34 copyrighted. 35 36 The original and principal author of md5.c is L. Peter Deutsch 37 <ghost@aladdin.com>. Other authors are noted in the change history 38 that follows (in reverse chronological order): 39 40 2002-04-13 lpd Clarified derivation from RFC 1321; now handles byte order 41 either statically or dynamically; added missing #include <string.h> 42 in library. 43 2002-03-11 lpd Corrected argument list for main(), and added int return 44 type, in test program and T value program. 45 2002-02-21 lpd Added missing #include <stdio.h> in test program. 46 2000-07-03 lpd Patched to eliminate warnings about "constant is 47 unsigned in ANSI C, signed in traditional"; made test program 48 self-checking. 49 1999-11-04 lpd Edited comments slightly for automatic TOC extraction. 50 1999-10-18 lpd Fixed typo in header comment (ansi2knr rather than md5). 51 1999-05-03 lpd Original version. 52 */ 53 54#include "md5.h" 55#include <string.h> 56#include <limits.h> 57 58#undef BYTE_ORDER /* 1 = big-endian, -1 = little-endian, 0 = unknown */ 59#ifdef ARCH_IS_BIG_ENDIAN 60# define BYTE_ORDER (ARCH_IS_BIG_ENDIAN ? 1 : -1) 61#else 62# define BYTE_ORDER 0 63#endif 64 65#define T_MASK ((md5_word_t)~0) 66#define T1 /* 0xd76aa478 */ (T_MASK ^ 0x28955b87) 67#define T2 /* 0xe8c7b756 */ (T_MASK ^ 0x173848a9) 68#define T3 0x242070db 69#define T4 /* 0xc1bdceee */ (T_MASK ^ 0x3e423111) 70#define T5 /* 0xf57c0faf */ (T_MASK ^ 0x0a83f050) 71#define T6 0x4787c62a 72#define T7 /* 0xa8304613 */ (T_MASK ^ 0x57cfb9ec) 73#define T8 /* 0xfd469501 */ (T_MASK ^ 0x02b96afe) 74#define T9 0x698098d8 75#define T10 /* 0x8b44f7af */ (T_MASK ^ 0x74bb0850) 76#define T11 /* 0xffff5bb1 */ (T_MASK ^ 0x0000a44e) 77#define T12 /* 0x895cd7be */ (T_MASK ^ 0x76a32841) 78#define T13 0x6b901122 79#define T14 /* 0xfd987193 */ (T_MASK ^ 0x02678e6c) 80#define T15 /* 0xa679438e */ (T_MASK ^ 0x5986bc71) 81#define T16 0x49b40821 82#define T17 /* 0xf61e2562 */ (T_MASK ^ 0x09e1da9d) 83#define T18 /* 0xc040b340 */ (T_MASK ^ 0x3fbf4cbf) 84#define T19 0x265e5a51 85#define T20 /* 0xe9b6c7aa */ (T_MASK ^ 0x16493855) 86#define T21 /* 0xd62f105d */ (T_MASK ^ 0x29d0efa2) 87#define T22 0x02441453 88#define T23 /* 0xd8a1e681 */ (T_MASK ^ 0x275e197e) 89#define T24 /* 0xe7d3fbc8 */ (T_MASK ^ 0x182c0437) 90#define T25 0x21e1cde6 91#define T26 /* 0xc33707d6 */ (T_MASK ^ 0x3cc8f829) 92#define T27 /* 0xf4d50d87 */ (T_MASK ^ 0x0b2af278) 93#define T28 0x455a14ed 94#define T29 /* 0xa9e3e905 */ (T_MASK ^ 0x561c16fa) 95#define T30 /* 0xfcefa3f8 */ (T_MASK ^ 0x03105c07) 96#define T31 0x676f02d9 97#define T32 /* 0x8d2a4c8a */ (T_MASK ^ 0x72d5b375) 98#define T33 /* 0xfffa3942 */ (T_MASK ^ 0x0005c6bd) 99#define T34 /* 0x8771f681 */ (T_MASK ^ 0x788e097e) 100#define T35 0x6d9d6122 101#define T36 /* 0xfde5380c */ (T_MASK ^ 0x021ac7f3) 102#define T37 /* 0xa4beea44 */ (T_MASK ^ 0x5b4115bb) 103#define T38 0x4bdecfa9 104#define T39 /* 0xf6bb4b60 */ (T_MASK ^ 0x0944b49f) 105#define T40 /* 0xbebfbc70 */ (T_MASK ^ 0x4140438f) 106#define T41 0x289b7ec6 107#define T42 /* 0xeaa127fa */ (T_MASK ^ 0x155ed805) 108#define T43 /* 0xd4ef3085 */ (T_MASK ^ 0x2b10cf7a) 109#define T44 0x04881d05 110#define T45 /* 0xd9d4d039 */ (T_MASK ^ 0x262b2fc6) 111#define T46 /* 0xe6db99e5 */ (T_MASK ^ 0x1924661a) 112#define T47 0x1fa27cf8 113#define T48 /* 0xc4ac5665 */ (T_MASK ^ 0x3b53a99a) 114#define T49 /* 0xf4292244 */ (T_MASK ^ 0x0bd6ddbb) 115#define T50 0x432aff97 116#define T51 /* 0xab9423a7 */ (T_MASK ^ 0x546bdc58) 117#define T52 /* 0xfc93a039 */ (T_MASK ^ 0x036c5fc6) 118#define T53 0x655b59c3 119#define T54 /* 0x8f0ccc92 */ (T_MASK ^ 0x70f3336d) 120#define T55 /* 0xffeff47d */ (T_MASK ^ 0x00100b82) 121#define T56 /* 0x85845dd1 */ (T_MASK ^ 0x7a7ba22e) 122#define T57 0x6fa87e4f 123#define T58 /* 0xfe2ce6e0 */ (T_MASK ^ 0x01d3191f) 124#define T59 /* 0xa3014314 */ (T_MASK ^ 0x5cfebceb) 125#define T60 0x4e0811a1 126#define T61 /* 0xf7537e82 */ (T_MASK ^ 0x08ac817d) 127#define T62 /* 0xbd3af235 */ (T_MASK ^ 0x42c50dca) 128#define T63 0x2ad7d2bb 129#define T64 /* 0xeb86d391 */ (T_MASK ^ 0x14792c6e) 130 131 132static void 133md5_process(md5_state_t *pms, const md5_byte_t *data /*[64]*/) 134{ 135 md5_word_t 136 a = pms->abcd[0], b = pms->abcd[1], 137 c = pms->abcd[2], d = pms->abcd[3]; 138 md5_word_t t; 139#if BYTE_ORDER > 0 140 /* Define storage only for big-endian CPUs. */ 141 md5_word_t X[16]; 142#else 143 /* Define storage for little-endian or both types of CPUs. */ 144 md5_word_t xbuf[16]; 145 const md5_word_t *X; 146#endif 147 148 { 149#if BYTE_ORDER == 0 150 /* 151 * Determine dynamically whether this is a big-endian or 152 * little-endian machine, since we can use a more efficient 153 * algorithm on the latter. 154 */ 155 static const int w = 1; 156 157 if (*((const md5_byte_t *)&w)) /* dynamic little-endian */ 158#endif 159#if BYTE_ORDER <= 0 /* little-endian */ 160 { 161 /* 162 * On little-endian machines, we can process properly aligned 163 * data without copying it. 164 */ 165 if (!((data - (const md5_byte_t *)0) & 3)) { 166 /* data are properly aligned */ 167 X = (const md5_word_t *)data; 168 } else { 169 /* not aligned */ 170 memcpy(xbuf, data, 64); 171 X = xbuf; 172 } 173 } 174#endif 175#if BYTE_ORDER == 0 176 else /* dynamic big-endian */ 177#endif 178#if BYTE_ORDER >= 0 /* big-endian */ 179 { 180 /* 181 * On big-endian machines, we must arrange the bytes in the 182 * right order. 183 */ 184 const md5_byte_t *xp = data; 185 int i; 186 187# if BYTE_ORDER == 0 188 X = xbuf; /* (dynamic only) */ 189# else 190# define xbuf X /* (static only) */ 191# endif 192 for (i = 0; i < 16; ++i, xp += 4) 193 xbuf[i] = xp[0] + (xp[1] << 8) + (xp[2] << 16) + (xp[3] << 24); 194 } 195#endif 196 } 197 198#define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32 - (n)))) 199 200 /* Round 1. */ 201 /* Let [abcd k s i] denote the operation 202 a = b + ((a + F(b,c,d) + X[k] + T[i]) <<< s). */ 203#define F(x, y, z) (((x) & (y)) | (~(x) & (z))) 204#define SET(a, b, c, d, k, s, Ti)\ 205 t = a + F(b,c,d) + X[k] + Ti;\ 206 a = ROTATE_LEFT(t, s) + b 207 /* Do the following 16 operations. */ 208 SET(a, b, c, d, 0, 7, T1); 209 SET(d, a, b, c, 1, 12, T2); 210 SET(c, d, a, b, 2, 17, T3); 211 SET(b, c, d, a, 3, 22, T4); 212 SET(a, b, c, d, 4, 7, T5); 213 SET(d, a, b, c, 5, 12, T6); 214 SET(c, d, a, b, 6, 17, T7); 215 SET(b, c, d, a, 7, 22, T8); 216 SET(a, b, c, d, 8, 7, T9); 217 SET(d, a, b, c, 9, 12, T10); 218 SET(c, d, a, b, 10, 17, T11); 219 SET(b, c, d, a, 11, 22, T12); 220 SET(a, b, c, d, 12, 7, T13); 221 SET(d, a, b, c, 13, 12, T14); 222 SET(c, d, a, b, 14, 17, T15); 223 SET(b, c, d, a, 15, 22, T16); 224#undef SET 225 226 /* Round 2. */ 227 /* Let [abcd k s i] denote the operation 228 a = b + ((a + G(b,c,d) + X[k] + T[i]) <<< s). */ 229#define G(x, y, z) (((x) & (z)) | ((y) & ~(z))) 230#define SET(a, b, c, d, k, s, Ti)\ 231 t = a + G(b,c,d) + X[k] + Ti;\ 232 a = ROTATE_LEFT(t, s) + b 233 /* Do the following 16 operations. */ 234 SET(a, b, c, d, 1, 5, T17); 235 SET(d, a, b, c, 6, 9, T18); 236 SET(c, d, a, b, 11, 14, T19); 237 SET(b, c, d, a, 0, 20, T20); 238 SET(a, b, c, d, 5, 5, T21); 239 SET(d, a, b, c, 10, 9, T22); 240 SET(c, d, a, b, 15, 14, T23); 241 SET(b, c, d, a, 4, 20, T24); 242 SET(a, b, c, d, 9, 5, T25); 243 SET(d, a, b, c, 14, 9, T26); 244 SET(c, d, a, b, 3, 14, T27); 245 SET(b, c, d, a, 8, 20, T28); 246 SET(a, b, c, d, 13, 5, T29); 247 SET(d, a, b, c, 2, 9, T30); 248 SET(c, d, a, b, 7, 14, T31); 249 SET(b, c, d, a, 12, 20, T32); 250#undef SET 251 252 /* Round 3. */ 253 /* Let [abcd k s t] denote the operation 254 a = b + ((a + H(b,c,d) + X[k] + T[i]) <<< s). */ 255#define H(x, y, z) ((x) ^ (y) ^ (z)) 256#define SET(a, b, c, d, k, s, Ti)\ 257 t = a + H(b,c,d) + X[k] + Ti;\ 258 a = ROTATE_LEFT(t, s) + b 259 /* Do the following 16 operations. */ 260 SET(a, b, c, d, 5, 4, T33); 261 SET(d, a, b, c, 8, 11, T34); 262 SET(c, d, a, b, 11, 16, T35); 263 SET(b, c, d, a, 14, 23, T36); 264 SET(a, b, c, d, 1, 4, T37); 265 SET(d, a, b, c, 4, 11, T38); 266 SET(c, d, a, b, 7, 16, T39); 267 SET(b, c, d, a, 10, 23, T40); 268 SET(a, b, c, d, 13, 4, T41); 269 SET(d, a, b, c, 0, 11, T42); 270 SET(c, d, a, b, 3, 16, T43); 271 SET(b, c, d, a, 6, 23, T44); 272 SET(a, b, c, d, 9, 4, T45); 273 SET(d, a, b, c, 12, 11, T46); 274 SET(c, d, a, b, 15, 16, T47); 275 SET(b, c, d, a, 2, 23, T48); 276#undef SET 277 278 /* Round 4. */ 279 /* Let [abcd k s t] denote the operation 280 a = b + ((a + I(b,c,d) + X[k] + T[i]) <<< s). */ 281#define I(x, y, z) ((y) ^ ((x) | ~(z))) 282#define SET(a, b, c, d, k, s, Ti)\ 283 t = a + I(b,c,d) + X[k] + Ti;\ 284 a = ROTATE_LEFT(t, s) + b 285 /* Do the following 16 operations. */ 286 SET(a, b, c, d, 0, 6, T49); 287 SET(d, a, b, c, 7, 10, T50); 288 SET(c, d, a, b, 14, 15, T51); 289 SET(b, c, d, a, 5, 21, T52); 290 SET(a, b, c, d, 12, 6, T53); 291 SET(d, a, b, c, 3, 10, T54); 292 SET(c, d, a, b, 10, 15, T55); 293 SET(b, c, d, a, 1, 21, T56); 294 SET(a, b, c, d, 8, 6, T57); 295 SET(d, a, b, c, 15, 10, T58); 296 SET(c, d, a, b, 6, 15, T59); 297 SET(b, c, d, a, 13, 21, T60); 298 SET(a, b, c, d, 4, 6, T61); 299 SET(d, a, b, c, 11, 10, T62); 300 SET(c, d, a, b, 2, 15, T63); 301 SET(b, c, d, a, 9, 21, T64); 302#undef SET 303 304 /* Then perform the following additions. (That is increment each 305 of the four registers by the value it had before this block 306 was started.) */ 307 pms->abcd[0] += a; 308 pms->abcd[1] += b; 309 pms->abcd[2] += c; 310 pms->abcd[3] += d; 311} 312 313void 314md5_init(md5_state_t *pms) 315{ 316 pms->count[0] = pms->count[1] = 0; 317 pms->abcd[0] = 0x67452301; 318 pms->abcd[1] = /*0xefcdab89*/ T_MASK ^ 0x10325476; 319 pms->abcd[2] = /*0x98badcfe*/ T_MASK ^ 0x67452301; 320 pms->abcd[3] = 0x10325476; 321} 322 323void 324md5_append(md5_state_t *pms, const md5_byte_t *data, int nbytes) 325{ 326 const md5_byte_t *p = data; 327 int left = nbytes; 328 int offset = (pms->count[0] >> 3) & 63; 329 md5_word_t nbits = (md5_word_t)(nbytes << 3); 330 331 if (nbytes <= 0) 332 return; 333 334 /* this special case is handled recursively */ 335 if (nbytes > INT_MAX - offset) { 336 int overlap; 337 338 /* handle the append in two steps to prevent overflow */ 339 overlap = 64 - offset; 340 341 md5_append(pms, data, overlap); 342 md5_append(pms, data + overlap, nbytes - overlap); 343 return; 344 } 345 346 /* Update the message length. */ 347 pms->count[1] += nbytes >> 29; 348 pms->count[0] += nbits; 349 if (pms->count[0] < nbits) 350 pms->count[1]++; 351 352 /* Process an initial partial block. */ 353 if (offset) { 354 int copy = (offset + nbytes > 64 ? 64 - offset : nbytes); 355 356 memcpy(pms->buf + offset, p, copy); 357 if (offset + copy < 64) 358 return; 359 p += copy; 360 left -= copy; 361 md5_process(pms, pms->buf); 362 } 363 364 /* Process full blocks. */ 365 for (; left >= 64; p += 64, left -= 64) 366 md5_process(pms, p); 367 368 /* Process a final partial block. */ 369 if (left) 370 memcpy(pms->buf, p, left); 371} 372 373void 374md5_finish(md5_state_t *pms, md5_byte_t digest[16]) 375{ 376 static const md5_byte_t pad[64] = { 377 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 378 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 379 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 380 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 381 }; 382 md5_byte_t data[8]; 383 int i; 384 385 /* Save the length before padding. */ 386 for (i = 0; i < 8; ++i) 387 data[i] = (md5_byte_t)(pms->count[i >> 2] >> ((i & 3) << 3)); 388 /* Pad to 56 bytes mod 64. */ 389 md5_append(pms, pad, ((55 - (pms->count[0] >> 3)) & 63) + 1); 390 /* Append the length. */ 391 md5_append(pms, data, 8); 392 for (i = 0; i < 16; ++i) 393 digest[i] = (md5_byte_t)(pms->abcd[i >> 2] >> ((i & 3) << 3)); 394}