1 /* vi: set sw=4 ts=4: */
3 * md5.c - Compute MD5 checksum of strings according to the
4 * definition of MD5 in RFC 1321 from April 1992.
6 * Written by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1995.
8 * Copyright (C) 1995-1999 Free Software Foundation, Inc.
9 * Copyright (C) 2001 Manuel Novoa III
10 * Copyright (C) 2003 Glenn L. McGrath
11 * Copyright (C) 2003 Erik Andersen
13 * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
26 # if CONFIG_MD5_SIZE_VS_SPEED < 0 || CONFIG_MD5_SIZE_VS_SPEED > 3
27 # define MD5_SIZE_VS_SPEED 2
29 # define MD5_SIZE_VS_SPEED CONFIG_MD5_SIZE_VS_SPEED
32 /* Initialize structure containing state of computation.
33 * (RFC 1321, 3.3: Step 3)
35 void md5_begin(md5_ctx_t *ctx)
46 /* These are the four functions used in the four steps of the MD5 algorithm
47 * and defined in the RFC 1321. The first function is a little bit optimized
48 * (as found in Colin Plumbs public domain implementation).
49 * #define FF(b, c, d) ((b & c) | (~b & d))
51 # define FF(b, c, d) (d ^ (b & (c ^ d)))
52 # define FG(b, c, d) FF (d, b, c)
53 # define FH(b, c, d) (b ^ c ^ d)
54 # define FI(b, c, d) (c ^ (b | ~d))
56 /* Hash a single block, 64 bytes long and 4-byte aligned. */
57 static void md5_hash_block(const void *buffer, md5_ctx_t *ctx)
59 uint32_t correct_words[16];
60 const uint32_t *words = buffer;
62 # if MD5_SIZE_VS_SPEED > 0
63 static const uint32_t C_array[] = {
65 0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee,
66 0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501,
67 0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be,
68 0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821,
70 0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa,
71 0xd62f105d, 0x2441453, 0xd8a1e681, 0xe7d3fbc8,
72 0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed,
73 0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a,
75 0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c,
76 0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70,
77 0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x4881d05,
78 0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665,
80 0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039,
81 0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1,
82 0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1,
83 0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391
86 static const char P_array[] = {
87 # if MD5_SIZE_VS_SPEED > 1
88 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, /* 1 */
89 # endif /* MD5_SIZE_VS_SPEED > 1 */
90 1, 6, 11, 0, 5, 10, 15, 4, 9, 14, 3, 8, 13, 2, 7, 12, /* 2 */
91 5, 8, 11, 14, 1, 4, 7, 10, 13, 0, 3, 6, 9, 12, 15, 2, /* 3 */
92 0, 7, 14, 5, 12, 3, 10, 1, 8, 15, 6, 13, 4, 11, 2, 9 /* 4 */
95 # if MD5_SIZE_VS_SPEED > 1
96 static const char S_array[] = {
102 # endif /* MD5_SIZE_VS_SPEED > 1 */
110 /* Process all bytes in the buffer with 64 bytes in each round of
112 uint32_t *cwp = correct_words;
118 # if MD5_SIZE_VS_SPEED > 1
119 # define CYCLIC(w, s) (w = (w << s) | (w >> (32 - s)))
127 for (i = 0; i < 16; i++) {
128 cwp[i] = SWAP_LE32(words[i]);
132 # if MD5_SIZE_VS_SPEED > 2
137 for (i = 0; i < 64; i++) {
154 temp += cwp[(int) (*pp++)] + *pc++;
155 CYCLIC(temp, ps[i & 3]);
167 for (i = 0; i < 16; i++) {
168 temp = A + FF(B, C, D) + cwp[(int) (*pp++)] + *pc++;
169 CYCLIC(temp, ps[i & 3]);
178 for (i = 0; i < 16; i++) {
179 temp = A + FG(B, C, D) + cwp[(int) (*pp++)] + *pc++;
180 CYCLIC(temp, ps[i & 3]);
188 for (i = 0; i < 16; i++) {
189 temp = A + FH(B, C, D) + cwp[(int) (*pp++)] + *pc++;
190 CYCLIC(temp, ps[i & 3]);
198 for (i = 0; i < 16; i++) {
199 temp = A + FI(B, C, D) + cwp[(int) (*pp++)] + *pc++;
200 CYCLIC(temp, ps[i & 3]);
208 # endif /* MD5_SIZE_VS_SPEED > 2 */
210 /* First round: using the given function, the context and a constant
211 the next context is computed. Because the algorithms processing
212 unit is a 32-bit word and it is determined to work on words in
213 little endian byte order we perhaps have to change the byte order
214 before the computation. To reduce the work for the next steps
215 we store the swapped words in the array CORRECT_WORDS. */
217 # define OP(a, b, c, d, s, T) \
220 a += FF (b, c, d) + (*cwp++ = SWAP_LE32(*words)) + T; \
227 /* It is unfortunate that C does not provide an operator for
228 cyclic rotation. Hope the C compiler is smart enough. */
229 /* gcc 2.95.4 seems to be --aaronl */
230 # define CYCLIC(w, s) (w = (w << s) | (w >> (32 - s)))
232 /* Before we start, one word to the strange constants.
233 They are defined in RFC 1321 as
235 T[i] = (int) (4294967296.0 * fabs (sin (i))), i=1..64
238 # if MD5_SIZE_VS_SPEED == 1
242 # endif /* MD5_SIZE_VS_SPEED */
245 # if MD5_SIZE_VS_SPEED == 1
247 for (i = 0; i < 4; i++) {
248 OP(A, B, C, D, 7, *pc++);
249 OP(D, A, B, C, 12, *pc++);
250 OP(C, D, A, B, 17, *pc++);
251 OP(B, C, D, A, 22, *pc++);
254 OP(A, B, C, D, 7, 0xd76aa478);
255 OP(D, A, B, C, 12, 0xe8c7b756);
256 OP(C, D, A, B, 17, 0x242070db);
257 OP(B, C, D, A, 22, 0xc1bdceee);
258 OP(A, B, C, D, 7, 0xf57c0faf);
259 OP(D, A, B, C, 12, 0x4787c62a);
260 OP(C, D, A, B, 17, 0xa8304613);
261 OP(B, C, D, A, 22, 0xfd469501);
262 OP(A, B, C, D, 7, 0x698098d8);
263 OP(D, A, B, C, 12, 0x8b44f7af);
264 OP(C, D, A, B, 17, 0xffff5bb1);
265 OP(B, C, D, A, 22, 0x895cd7be);
266 OP(A, B, C, D, 7, 0x6b901122);
267 OP(D, A, B, C, 12, 0xfd987193);
268 OP(C, D, A, B, 17, 0xa679438e);
269 OP(B, C, D, A, 22, 0x49b40821);
270 # endif /* MD5_SIZE_VS_SPEED == 1 */
272 /* For the second to fourth round we have the possibly swapped words
273 in CORRECT_WORDS. Redefine the macro to take an additional first
274 argument specifying the function to use. */
276 # define OP(f, a, b, c, d, k, s, T) \
279 a += f (b, c, d) + correct_words[k] + T; \
286 # if MD5_SIZE_VS_SPEED == 1
288 for (i = 0; i < 4; i++) {
289 OP(FG, A, B, C, D, (int) (*pp++), 5, *pc++);
290 OP(FG, D, A, B, C, (int) (*pp++), 9, *pc++);
291 OP(FG, C, D, A, B, (int) (*pp++), 14, *pc++);
292 OP(FG, B, C, D, A, (int) (*pp++), 20, *pc++);
295 OP(FG, A, B, C, D, 1, 5, 0xf61e2562);
296 OP(FG, D, A, B, C, 6, 9, 0xc040b340);
297 OP(FG, C, D, A, B, 11, 14, 0x265e5a51);
298 OP(FG, B, C, D, A, 0, 20, 0xe9b6c7aa);
299 OP(FG, A, B, C, D, 5, 5, 0xd62f105d);
300 OP(FG, D, A, B, C, 10, 9, 0x02441453);
301 OP(FG, C, D, A, B, 15, 14, 0xd8a1e681);
302 OP(FG, B, C, D, A, 4, 20, 0xe7d3fbc8);
303 OP(FG, A, B, C, D, 9, 5, 0x21e1cde6);
304 OP(FG, D, A, B, C, 14, 9, 0xc33707d6);
305 OP(FG, C, D, A, B, 3, 14, 0xf4d50d87);
306 OP(FG, B, C, D, A, 8, 20, 0x455a14ed);
307 OP(FG, A, B, C, D, 13, 5, 0xa9e3e905);
308 OP(FG, D, A, B, C, 2, 9, 0xfcefa3f8);
309 OP(FG, C, D, A, B, 7, 14, 0x676f02d9);
310 OP(FG, B, C, D, A, 12, 20, 0x8d2a4c8a);
311 # endif /* MD5_SIZE_VS_SPEED == 1 */
314 # if MD5_SIZE_VS_SPEED == 1
315 for (i = 0; i < 4; i++) {
316 OP(FH, A, B, C, D, (int) (*pp++), 4, *pc++);
317 OP(FH, D, A, B, C, (int) (*pp++), 11, *pc++);
318 OP(FH, C, D, A, B, (int) (*pp++), 16, *pc++);
319 OP(FH, B, C, D, A, (int) (*pp++), 23, *pc++);
322 OP(FH, A, B, C, D, 5, 4, 0xfffa3942);
323 OP(FH, D, A, B, C, 8, 11, 0x8771f681);
324 OP(FH, C, D, A, B, 11, 16, 0x6d9d6122);
325 OP(FH, B, C, D, A, 14, 23, 0xfde5380c);
326 OP(FH, A, B, C, D, 1, 4, 0xa4beea44);
327 OP(FH, D, A, B, C, 4, 11, 0x4bdecfa9);
328 OP(FH, C, D, A, B, 7, 16, 0xf6bb4b60);
329 OP(FH, B, C, D, A, 10, 23, 0xbebfbc70);
330 OP(FH, A, B, C, D, 13, 4, 0x289b7ec6);
331 OP(FH, D, A, B, C, 0, 11, 0xeaa127fa);
332 OP(FH, C, D, A, B, 3, 16, 0xd4ef3085);
333 OP(FH, B, C, D, A, 6, 23, 0x04881d05);
334 OP(FH, A, B, C, D, 9, 4, 0xd9d4d039);
335 OP(FH, D, A, B, C, 12, 11, 0xe6db99e5);
336 OP(FH, C, D, A, B, 15, 16, 0x1fa27cf8);
337 OP(FH, B, C, D, A, 2, 23, 0xc4ac5665);
338 # endif /* MD5_SIZE_VS_SPEED == 1 */
341 # if MD5_SIZE_VS_SPEED == 1
342 for (i = 0; i < 4; i++) {
343 OP(FI, A, B, C, D, (int) (*pp++), 6, *pc++);
344 OP(FI, D, A, B, C, (int) (*pp++), 10, *pc++);
345 OP(FI, C, D, A, B, (int) (*pp++), 15, *pc++);
346 OP(FI, B, C, D, A, (int) (*pp++), 21, *pc++);
349 OP(FI, A, B, C, D, 0, 6, 0xf4292244);
350 OP(FI, D, A, B, C, 7, 10, 0x432aff97);
351 OP(FI, C, D, A, B, 14, 15, 0xab9423a7);
352 OP(FI, B, C, D, A, 5, 21, 0xfc93a039);
353 OP(FI, A, B, C, D, 12, 6, 0x655b59c3);
354 OP(FI, D, A, B, C, 3, 10, 0x8f0ccc92);
355 OP(FI, C, D, A, B, 10, 15, 0xffeff47d);
356 OP(FI, B, C, D, A, 1, 21, 0x85845dd1);
357 OP(FI, A, B, C, D, 8, 6, 0x6fa87e4f);
358 OP(FI, D, A, B, C, 15, 10, 0xfe2ce6e0);
359 OP(FI, C, D, A, B, 6, 15, 0xa3014314);
360 OP(FI, B, C, D, A, 13, 21, 0x4e0811a1);
361 OP(FI, A, B, C, D, 4, 6, 0xf7537e82);
362 OP(FI, D, A, B, C, 11, 10, 0xbd3af235);
363 OP(FI, C, D, A, B, 2, 15, 0x2ad7d2bb);
364 OP(FI, B, C, D, A, 9, 21, 0xeb86d391);
365 # endif /* MD5_SIZE_VS_SPEED == 1 */
366 # endif /* MD5_SIZE_VS_SPEED > 1 */
368 /* Add the starting values of the context. */
374 /* Put checksum in context given as argument. */
381 /* Feed data through a temporary buffer to call md5_hash_aligned_block()
382 * with chunks of data that are 4-byte aligned and a multiple of 64 bytes.
383 * This function's internal buffer remembers previous data until it has 64
384 * bytes worth to pass on. Call md5_end() to flush this buffer. */
386 void md5_hash(const void *buffer, size_t len, md5_ctx_t *ctx)
388 char *buf=(char *)buffer;
390 /* RFC 1321 specifies the possible length of the file up to 2^64 bits,
391 * Here we only track the number of bytes. */
395 // Process all input.
398 int i = 64 - ctx->buflen;
400 // Copy data into aligned buffer.
402 if (i > len) i = len;
403 memcpy(ctx->buffer + ctx->buflen, buf, i);
408 // When buffer fills up, process it.
410 if (ctx->buflen == 64) {
411 md5_hash_block(ctx->buffer, ctx);
417 /* Process the remaining bytes in the buffer and put result from CTX
418 * in first 16 bytes following RESBUF. The result is always in little
419 * endian byte order, so that a byte-wise output yields to the wanted
420 * ASCII representation of the message digest.
422 * IMPORTANT: On some systems it is required that RESBUF is correctly
423 * aligned for a 32 bits value.
425 void *md5_end(void *resbuf, md5_ctx_t *ctx)
427 char *buf = ctx->buffer;
430 /* Pad data to block size. */
432 buf[ctx->buflen++] = 0x80;
433 memset(buf + ctx->buflen, 0, 128 - ctx->buflen);
435 /* Put the 64-bit file length in *bits* at the end of the buffer. */
437 if (ctx->buflen > 56) buf += 64;
438 for (i = 0; i < 8; i++) buf[56 + i] = ctx->total >> (i*8);
440 /* Process last bytes. */
441 if (buf != ctx->buffer) md5_hash_block(ctx->buffer, ctx);
442 md5_hash_block(buf, ctx);
444 /* Put result from CTX in first 16 bytes following RESBUF. The result is
445 * always in little endian byte order, so that a byte-wise output yields
446 * to the wanted ASCII representation of the message digest.
448 * IMPORTANT: On some systems it is required that RESBUF is correctly
449 * aligned for a 32 bits value.
451 ((uint32_t *) resbuf)[0] = SWAP_LE32(ctx->A);
452 ((uint32_t *) resbuf)[1] = SWAP_LE32(ctx->B);
453 ((uint32_t *) resbuf)[2] = SWAP_LE32(ctx->C);
454 ((uint32_t *) resbuf)[3] = SWAP_LE32(ctx->D);