2 * md5.c - Compute MD5 checksum of strings according to the
3 * definition of MD5 in RFC 1321 from April 1992.
5 * Written by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1995.
7 * Copyright (C) 1995-1999 Free Software Foundation, Inc.
8 * Copyright (C) 2001 Manuel Novoa III
9 * Copyright (C) 2003 Glenn L. McGrath
10 * Copyright (C) 2003 Erik Andersen
12 * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
24 # if CONFIG_MD5_SIZE_VS_SPEED < 0 || CONFIG_MD5_SIZE_VS_SPEED > 3
25 # define MD5_SIZE_VS_SPEED 2
27 # define MD5_SIZE_VS_SPEED CONFIG_MD5_SIZE_VS_SPEED
30 /* Handle endian-ness */
33 # elif defined(bswap_32)
34 # define SWAP(n) bswap_32(n)
36 # define SWAP(n) ((n << 24) | ((n&65280)<<8) | ((n&16711680)>>8) | (n>>24))
39 # if MD5_SIZE_VS_SPEED == 0
40 /* This array contains the bytes used to pad the buffer to the next
41 64-byte boundary. (RFC 1321, 3.1: Step 1) */
42 static const unsigned char fillbuf[64] = { 0x80, 0 /* , 0, 0, ... */ };
43 # endif /* MD5_SIZE_VS_SPEED == 0 */
45 /* Initialize structure containing state of computation.
46 * (RFC 1321, 3.3: Step 3)
48 void md5_begin(md5_ctx_t *ctx)
55 ctx->total[0] = ctx->total[1] = 0;
59 /* These are the four functions used in the four steps of the MD5 algorithm
60 * and defined in the RFC 1321. The first function is a little bit optimized
61 * (as found in Colin Plumbs public domain implementation).
62 * #define FF(b, c, d) ((b & c) | (~b & d))
64 # define FF(b, c, d) (d ^ (b & (c ^ d)))
65 # define FG(b, c, d) FF (d, b, c)
66 # define FH(b, c, d) (b ^ c ^ d)
67 # define FI(b, c, d) (c ^ (b | ~d))
69 /* Starting with the result of former calls of this function (or the
70 * initialization function update the context for the next LEN bytes
72 * It is necessary that LEN is a multiple of 64!!!
74 void md5_hash_block(const void *buffer, size_t len, md5_ctx_t *ctx)
76 uint32_t correct_words[16];
77 const uint32_t *words = buffer;
78 size_t nwords = len / sizeof(uint32_t);
79 const uint32_t *endp = words + nwords;
81 # if MD5_SIZE_VS_SPEED > 0
82 static const uint32_t C_array[] = {
84 0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee,
85 0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501,
86 0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be,
87 0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821,
89 0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa,
90 0xd62f105d, 0x2441453, 0xd8a1e681, 0xe7d3fbc8,
91 0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed,
92 0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a,
94 0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c,
95 0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70,
96 0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x4881d05,
97 0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665,
99 0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039,
100 0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1,
101 0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1,
102 0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391
105 static const char P_array[] = {
106 # if MD5_SIZE_VS_SPEED > 1
107 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, /* 1 */
108 # endif /* MD5_SIZE_VS_SPEED > 1 */
109 1, 6, 11, 0, 5, 10, 15, 4, 9, 14, 3, 8, 13, 2, 7, 12, /* 2 */
110 5, 8, 11, 14, 1, 4, 7, 10, 13, 0, 3, 6, 9, 12, 15, 2, /* 3 */
111 0, 7, 14, 5, 12, 3, 10, 1, 8, 15, 6, 13, 4, 11, 2, 9 /* 4 */
114 # if MD5_SIZE_VS_SPEED > 1
115 static const char S_array[] = {
121 # endif /* MD5_SIZE_VS_SPEED > 1 */
129 /* First increment the byte count. RFC 1321 specifies the possible
130 length of the file up to 2^64 bits. Here we only compute the
131 number of bytes. Do a double word increment. */
132 ctx->total[0] += len;
133 if (ctx->total[0] < len)
136 /* Process all bytes in the buffer with 64 bytes in each round of
138 while (words < endp) {
139 uint32_t *cwp = correct_words;
145 # if MD5_SIZE_VS_SPEED > 1
146 # define CYCLIC(w, s) (w = (w << s) | (w >> (32 - s)))
154 for (i = 0; i < 16; i++) {
155 cwp[i] = SWAP(words[i]);
159 # if MD5_SIZE_VS_SPEED > 2
164 for (i = 0; i < 64; i++) {
181 temp += cwp[(int) (*pp++)] + *pc++;
182 CYCLIC(temp, ps[i & 3]);
194 for (i = 0; i < 16; i++) {
195 temp = A + FF(B, C, D) + cwp[(int) (*pp++)] + *pc++;
196 CYCLIC(temp, ps[i & 3]);
205 for (i = 0; i < 16; i++) {
206 temp = A + FG(B, C, D) + cwp[(int) (*pp++)] + *pc++;
207 CYCLIC(temp, ps[i & 3]);
215 for (i = 0; i < 16; i++) {
216 temp = A + FH(B, C, D) + cwp[(int) (*pp++)] + *pc++;
217 CYCLIC(temp, ps[i & 3]);
225 for (i = 0; i < 16; i++) {
226 temp = A + FI(B, C, D) + cwp[(int) (*pp++)] + *pc++;
227 CYCLIC(temp, ps[i & 3]);
235 # endif /* MD5_SIZE_VS_SPEED > 2 */
237 /* First round: using the given function, the context and a constant
238 the next context is computed. Because the algorithms processing
239 unit is a 32-bit word and it is determined to work on words in
240 little endian byte order we perhaps have to change the byte order
241 before the computation. To reduce the work for the next steps
242 we store the swapped words in the array CORRECT_WORDS. */
244 # define OP(a, b, c, d, s, T) \
247 a += FF (b, c, d) + (*cwp++ = SWAP (*words)) + T; \
254 /* It is unfortunate that C does not provide an operator for
255 cyclic rotation. Hope the C compiler is smart enough. */
256 /* gcc 2.95.4 seems to be --aaronl */
257 # define CYCLIC(w, s) (w = (w << s) | (w >> (32 - s)))
259 /* Before we start, one word to the strange constants.
260 They are defined in RFC 1321 as
262 T[i] = (int) (4294967296.0 * fabs (sin (i))), i=1..64
265 # if MD5_SIZE_VS_SPEED == 1
269 # endif /* MD5_SIZE_VS_SPEED */
272 # if MD5_SIZE_VS_SPEED == 1
274 for (i = 0; i < 4; i++) {
275 OP(A, B, C, D, 7, *pc++);
276 OP(D, A, B, C, 12, *pc++);
277 OP(C, D, A, B, 17, *pc++);
278 OP(B, C, D, A, 22, *pc++);
281 OP(A, B, C, D, 7, 0xd76aa478);
282 OP(D, A, B, C, 12, 0xe8c7b756);
283 OP(C, D, A, B, 17, 0x242070db);
284 OP(B, C, D, A, 22, 0xc1bdceee);
285 OP(A, B, C, D, 7, 0xf57c0faf);
286 OP(D, A, B, C, 12, 0x4787c62a);
287 OP(C, D, A, B, 17, 0xa8304613);
288 OP(B, C, D, A, 22, 0xfd469501);
289 OP(A, B, C, D, 7, 0x698098d8);
290 OP(D, A, B, C, 12, 0x8b44f7af);
291 OP(C, D, A, B, 17, 0xffff5bb1);
292 OP(B, C, D, A, 22, 0x895cd7be);
293 OP(A, B, C, D, 7, 0x6b901122);
294 OP(D, A, B, C, 12, 0xfd987193);
295 OP(C, D, A, B, 17, 0xa679438e);
296 OP(B, C, D, A, 22, 0x49b40821);
297 # endif /* MD5_SIZE_VS_SPEED == 1 */
299 /* For the second to fourth round we have the possibly swapped words
300 in CORRECT_WORDS. Redefine the macro to take an additional first
301 argument specifying the function to use. */
303 # define OP(f, a, b, c, d, k, s, T) \
306 a += f (b, c, d) + correct_words[k] + T; \
313 # if MD5_SIZE_VS_SPEED == 1
315 for (i = 0; i < 4; i++) {
316 OP(FG, A, B, C, D, (int) (*pp++), 5, *pc++);
317 OP(FG, D, A, B, C, (int) (*pp++), 9, *pc++);
318 OP(FG, C, D, A, B, (int) (*pp++), 14, *pc++);
319 OP(FG, B, C, D, A, (int) (*pp++), 20, *pc++);
322 OP(FG, A, B, C, D, 1, 5, 0xf61e2562);
323 OP(FG, D, A, B, C, 6, 9, 0xc040b340);
324 OP(FG, C, D, A, B, 11, 14, 0x265e5a51);
325 OP(FG, B, C, D, A, 0, 20, 0xe9b6c7aa);
326 OP(FG, A, B, C, D, 5, 5, 0xd62f105d);
327 OP(FG, D, A, B, C, 10, 9, 0x02441453);
328 OP(FG, C, D, A, B, 15, 14, 0xd8a1e681);
329 OP(FG, B, C, D, A, 4, 20, 0xe7d3fbc8);
330 OP(FG, A, B, C, D, 9, 5, 0x21e1cde6);
331 OP(FG, D, A, B, C, 14, 9, 0xc33707d6);
332 OP(FG, C, D, A, B, 3, 14, 0xf4d50d87);
333 OP(FG, B, C, D, A, 8, 20, 0x455a14ed);
334 OP(FG, A, B, C, D, 13, 5, 0xa9e3e905);
335 OP(FG, D, A, B, C, 2, 9, 0xfcefa3f8);
336 OP(FG, C, D, A, B, 7, 14, 0x676f02d9);
337 OP(FG, B, C, D, A, 12, 20, 0x8d2a4c8a);
338 # endif /* MD5_SIZE_VS_SPEED == 1 */
341 # if MD5_SIZE_VS_SPEED == 1
342 for (i = 0; i < 4; i++) {
343 OP(FH, A, B, C, D, (int) (*pp++), 4, *pc++);
344 OP(FH, D, A, B, C, (int) (*pp++), 11, *pc++);
345 OP(FH, C, D, A, B, (int) (*pp++), 16, *pc++);
346 OP(FH, B, C, D, A, (int) (*pp++), 23, *pc++);
349 OP(FH, A, B, C, D, 5, 4, 0xfffa3942);
350 OP(FH, D, A, B, C, 8, 11, 0x8771f681);
351 OP(FH, C, D, A, B, 11, 16, 0x6d9d6122);
352 OP(FH, B, C, D, A, 14, 23, 0xfde5380c);
353 OP(FH, A, B, C, D, 1, 4, 0xa4beea44);
354 OP(FH, D, A, B, C, 4, 11, 0x4bdecfa9);
355 OP(FH, C, D, A, B, 7, 16, 0xf6bb4b60);
356 OP(FH, B, C, D, A, 10, 23, 0xbebfbc70);
357 OP(FH, A, B, C, D, 13, 4, 0x289b7ec6);
358 OP(FH, D, A, B, C, 0, 11, 0xeaa127fa);
359 OP(FH, C, D, A, B, 3, 16, 0xd4ef3085);
360 OP(FH, B, C, D, A, 6, 23, 0x04881d05);
361 OP(FH, A, B, C, D, 9, 4, 0xd9d4d039);
362 OP(FH, D, A, B, C, 12, 11, 0xe6db99e5);
363 OP(FH, C, D, A, B, 15, 16, 0x1fa27cf8);
364 OP(FH, B, C, D, A, 2, 23, 0xc4ac5665);
365 # endif /* MD5_SIZE_VS_SPEED == 1 */
368 # if MD5_SIZE_VS_SPEED == 1
369 for (i = 0; i < 4; i++) {
370 OP(FI, A, B, C, D, (int) (*pp++), 6, *pc++);
371 OP(FI, D, A, B, C, (int) (*pp++), 10, *pc++);
372 OP(FI, C, D, A, B, (int) (*pp++), 15, *pc++);
373 OP(FI, B, C, D, A, (int) (*pp++), 21, *pc++);
376 OP(FI, A, B, C, D, 0, 6, 0xf4292244);
377 OP(FI, D, A, B, C, 7, 10, 0x432aff97);
378 OP(FI, C, D, A, B, 14, 15, 0xab9423a7);
379 OP(FI, B, C, D, A, 5, 21, 0xfc93a039);
380 OP(FI, A, B, C, D, 12, 6, 0x655b59c3);
381 OP(FI, D, A, B, C, 3, 10, 0x8f0ccc92);
382 OP(FI, C, D, A, B, 10, 15, 0xffeff47d);
383 OP(FI, B, C, D, A, 1, 21, 0x85845dd1);
384 OP(FI, A, B, C, D, 8, 6, 0x6fa87e4f);
385 OP(FI, D, A, B, C, 15, 10, 0xfe2ce6e0);
386 OP(FI, C, D, A, B, 6, 15, 0xa3014314);
387 OP(FI, B, C, D, A, 13, 21, 0x4e0811a1);
388 OP(FI, A, B, C, D, 4, 6, 0xf7537e82);
389 OP(FI, D, A, B, C, 11, 10, 0xbd3af235);
390 OP(FI, C, D, A, B, 2, 15, 0x2ad7d2bb);
391 OP(FI, B, C, D, A, 9, 21, 0xeb86d391);
392 # endif /* MD5_SIZE_VS_SPEED == 1 */
393 # endif /* MD5_SIZE_VS_SPEED > 1 */
395 /* Add the starting values of the context. */
402 /* Put checksum in context given as argument. */
409 /* Starting with the result of former calls of this function (or the
410 * initialization function update the context for the next LEN bytes
411 * starting at BUFFER.
412 * It is NOT required that LEN is a multiple of 64.
415 static void md5_hash_bytes(const void *buffer, size_t len, md5_ctx_t *ctx)
417 /* When we already have some bits in our internal buffer concatenate
418 both inputs first. */
419 if (ctx->buflen != 0) {
420 size_t left_over = ctx->buflen;
421 size_t add = 128 - left_over > len ? len : 128 - left_over;
423 memcpy(&ctx->buffer[left_over], buffer, add);
426 if (left_over + add > 64) {
427 md5_hash_block(ctx->buffer, (left_over + add) & ~63, ctx);
428 /* The regions in the following copy operation cannot overlap. */
429 memcpy(ctx->buffer, &ctx->buffer[(left_over + add) & ~63],
430 (left_over + add) & 63);
431 ctx->buflen = (left_over + add) & 63;
434 buffer = (const char *) buffer + add;
438 /* Process available complete blocks. */
440 md5_hash_block(buffer, len & ~63, ctx);
441 buffer = (const char *) buffer + (len & ~63);
445 /* Move remaining bytes in internal buffer. */
447 memcpy(ctx->buffer, buffer, len);
452 void md5_hash(const void *data, size_t length, md5_ctx_t *ctx)
454 if (length % 64 == 0) {
455 md5_hash_block(data, length, ctx);
457 md5_hash_bytes(data, length, ctx);
461 /* Process the remaining bytes in the buffer and put result from CTX
462 * in first 16 bytes following RESBUF. The result is always in little
463 * endian byte order, so that a byte-wise output yields to the wanted
464 * ASCII representation of the message digest.
466 * IMPORTANT: On some systems it is required that RESBUF is correctly
467 * aligned for a 32 bits value.
469 void *md5_end(void *resbuf, md5_ctx_t *ctx)
471 /* Take yet unprocessed bytes into account. */
472 uint32_t bytes = ctx->buflen;
475 /* Now count remaining bytes. */
476 ctx->total[0] += bytes;
477 if (ctx->total[0] < bytes)
480 pad = bytes >= 56 ? 64 + 56 - bytes : 56 - bytes;
481 # if MD5_SIZE_VS_SPEED > 0
482 memset(&ctx->buffer[bytes], 0, pad);
483 ctx->buffer[bytes] = 0x80;
485 memcpy(&ctx->buffer[bytes], fillbuf, pad);
486 # endif /* MD5_SIZE_VS_SPEED > 0 */
488 /* Put the 64-bit file length in *bits* at the end of the buffer. */
489 *(uint32_t *) & ctx->buffer[bytes + pad] = SWAP(ctx->total[0] << 3);
490 *(uint32_t *) & ctx->buffer[bytes + pad + 4] =
491 SWAP(((ctx->total[1] << 3) | (ctx->total[0] >> 29)));
493 /* Process last bytes. */
494 md5_hash_block(ctx->buffer, bytes + pad + 8, ctx);
496 /* Put result from CTX in first 16 bytes following RESBUF. The result is
497 * always in little endian byte order, so that a byte-wise output yields
498 * to the wanted ASCII representation of the message digest.
500 * IMPORTANT: On some systems it is required that RESBUF is correctly
501 * aligned for a 32 bits value.
503 ((uint32_t *) resbuf)[0] = SWAP(ctx->A);
504 ((uint32_t *) resbuf)[1] = SWAP(ctx->B);
505 ((uint32_t *) resbuf)[2] = SWAP(ctx->C);
506 ((uint32_t *) resbuf)[3] = SWAP(ctx->D);