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 /* Initialize structure containing state of computation.
31 * (RFC 1321, 3.3: Step 3)
33 void md5_begin(md5_ctx_t *ctx)
44 /* These are the four functions used in the four steps of the MD5 algorithm
45 * and defined in the RFC 1321. The first function is a little bit optimized
46 * (as found in Colin Plumbs public domain implementation).
47 * #define FF(b, c, d) ((b & c) | (~b & d))
49 # define FF(b, c, d) (d ^ (b & (c ^ d)))
50 # define FG(b, c, d) FF (d, b, c)
51 # define FH(b, c, d) (b ^ c ^ d)
52 # define FI(b, c, d) (c ^ (b | ~d))
54 /* Hash a single block, 64 bytes long and 4-byte aligned. */
55 static void md5_hash_block(const void *buffer, md5_ctx_t *ctx)
57 uint32_t correct_words[16];
58 const uint32_t *words = buffer;
60 # if MD5_SIZE_VS_SPEED > 0
61 static const uint32_t C_array[] = {
63 0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee,
64 0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501,
65 0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be,
66 0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821,
68 0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa,
69 0xd62f105d, 0x2441453, 0xd8a1e681, 0xe7d3fbc8,
70 0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed,
71 0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a,
73 0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c,
74 0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70,
75 0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x4881d05,
76 0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665,
78 0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039,
79 0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1,
80 0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1,
81 0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391
84 static const char P_array[] = {
85 # if MD5_SIZE_VS_SPEED > 1
86 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, /* 1 */
87 # endif /* MD5_SIZE_VS_SPEED > 1 */
88 1, 6, 11, 0, 5, 10, 15, 4, 9, 14, 3, 8, 13, 2, 7, 12, /* 2 */
89 5, 8, 11, 14, 1, 4, 7, 10, 13, 0, 3, 6, 9, 12, 15, 2, /* 3 */
90 0, 7, 14, 5, 12, 3, 10, 1, 8, 15, 6, 13, 4, 11, 2, 9 /* 4 */
93 # if MD5_SIZE_VS_SPEED > 1
94 static const char S_array[] = {
100 # endif /* MD5_SIZE_VS_SPEED > 1 */
108 /* Process all bytes in the buffer with 64 bytes in each round of
110 uint32_t *cwp = correct_words;
116 # if MD5_SIZE_VS_SPEED > 1
117 # define CYCLIC(w, s) (w = (w << s) | (w >> (32 - s)))
125 for (i = 0; i < 16; i++) {
126 cwp[i] = SWAP_LE32(words[i]);
130 # if MD5_SIZE_VS_SPEED > 2
135 for (i = 0; i < 64; i++) {
152 temp += cwp[(int) (*pp++)] + *pc++;
153 CYCLIC(temp, ps[i & 3]);
165 for (i = 0; i < 16; i++) {
166 temp = A + FF(B, C, D) + cwp[(int) (*pp++)] + *pc++;
167 CYCLIC(temp, ps[i & 3]);
176 for (i = 0; i < 16; i++) {
177 temp = A + FG(B, C, D) + cwp[(int) (*pp++)] + *pc++;
178 CYCLIC(temp, ps[i & 3]);
186 for (i = 0; i < 16; i++) {
187 temp = A + FH(B, C, D) + cwp[(int) (*pp++)] + *pc++;
188 CYCLIC(temp, ps[i & 3]);
196 for (i = 0; i < 16; i++) {
197 temp = A + FI(B, C, D) + cwp[(int) (*pp++)] + *pc++;
198 CYCLIC(temp, ps[i & 3]);
206 # endif /* MD5_SIZE_VS_SPEED > 2 */
208 /* First round: using the given function, the context and a constant
209 the next context is computed. Because the algorithms processing
210 unit is a 32-bit word and it is determined to work on words in
211 little endian byte order we perhaps have to change the byte order
212 before the computation. To reduce the work for the next steps
213 we store the swapped words in the array CORRECT_WORDS. */
215 # define OP(a, b, c, d, s, T) \
218 a += FF (b, c, d) + (*cwp++ = SWAP_LE32(*words)) + T; \
225 /* It is unfortunate that C does not provide an operator for
226 cyclic rotation. Hope the C compiler is smart enough. */
227 /* gcc 2.95.4 seems to be --aaronl */
228 # define CYCLIC(w, s) (w = (w << s) | (w >> (32 - s)))
230 /* Before we start, one word to the strange constants.
231 They are defined in RFC 1321 as
233 T[i] = (int) (4294967296.0 * fabs (sin (i))), i=1..64
236 # if MD5_SIZE_VS_SPEED == 1
240 # endif /* MD5_SIZE_VS_SPEED */
243 # if MD5_SIZE_VS_SPEED == 1
245 for (i = 0; i < 4; i++) {
246 OP(A, B, C, D, 7, *pc++);
247 OP(D, A, B, C, 12, *pc++);
248 OP(C, D, A, B, 17, *pc++);
249 OP(B, C, D, A, 22, *pc++);
252 OP(A, B, C, D, 7, 0xd76aa478);
253 OP(D, A, B, C, 12, 0xe8c7b756);
254 OP(C, D, A, B, 17, 0x242070db);
255 OP(B, C, D, A, 22, 0xc1bdceee);
256 OP(A, B, C, D, 7, 0xf57c0faf);
257 OP(D, A, B, C, 12, 0x4787c62a);
258 OP(C, D, A, B, 17, 0xa8304613);
259 OP(B, C, D, A, 22, 0xfd469501);
260 OP(A, B, C, D, 7, 0x698098d8);
261 OP(D, A, B, C, 12, 0x8b44f7af);
262 OP(C, D, A, B, 17, 0xffff5bb1);
263 OP(B, C, D, A, 22, 0x895cd7be);
264 OP(A, B, C, D, 7, 0x6b901122);
265 OP(D, A, B, C, 12, 0xfd987193);
266 OP(C, D, A, B, 17, 0xa679438e);
267 OP(B, C, D, A, 22, 0x49b40821);
268 # endif /* MD5_SIZE_VS_SPEED == 1 */
270 /* For the second to fourth round we have the possibly swapped words
271 in CORRECT_WORDS. Redefine the macro to take an additional first
272 argument specifying the function to use. */
274 # define OP(f, a, b, c, d, k, s, T) \
277 a += f (b, c, d) + correct_words[k] + T; \
284 # if MD5_SIZE_VS_SPEED == 1
286 for (i = 0; i < 4; i++) {
287 OP(FG, A, B, C, D, (int) (*pp++), 5, *pc++);
288 OP(FG, D, A, B, C, (int) (*pp++), 9, *pc++);
289 OP(FG, C, D, A, B, (int) (*pp++), 14, *pc++);
290 OP(FG, B, C, D, A, (int) (*pp++), 20, *pc++);
293 OP(FG, A, B, C, D, 1, 5, 0xf61e2562);
294 OP(FG, D, A, B, C, 6, 9, 0xc040b340);
295 OP(FG, C, D, A, B, 11, 14, 0x265e5a51);
296 OP(FG, B, C, D, A, 0, 20, 0xe9b6c7aa);
297 OP(FG, A, B, C, D, 5, 5, 0xd62f105d);
298 OP(FG, D, A, B, C, 10, 9, 0x02441453);
299 OP(FG, C, D, A, B, 15, 14, 0xd8a1e681);
300 OP(FG, B, C, D, A, 4, 20, 0xe7d3fbc8);
301 OP(FG, A, B, C, D, 9, 5, 0x21e1cde6);
302 OP(FG, D, A, B, C, 14, 9, 0xc33707d6);
303 OP(FG, C, D, A, B, 3, 14, 0xf4d50d87);
304 OP(FG, B, C, D, A, 8, 20, 0x455a14ed);
305 OP(FG, A, B, C, D, 13, 5, 0xa9e3e905);
306 OP(FG, D, A, B, C, 2, 9, 0xfcefa3f8);
307 OP(FG, C, D, A, B, 7, 14, 0x676f02d9);
308 OP(FG, B, C, D, A, 12, 20, 0x8d2a4c8a);
309 # endif /* MD5_SIZE_VS_SPEED == 1 */
312 # if MD5_SIZE_VS_SPEED == 1
313 for (i = 0; i < 4; i++) {
314 OP(FH, A, B, C, D, (int) (*pp++), 4, *pc++);
315 OP(FH, D, A, B, C, (int) (*pp++), 11, *pc++);
316 OP(FH, C, D, A, B, (int) (*pp++), 16, *pc++);
317 OP(FH, B, C, D, A, (int) (*pp++), 23, *pc++);
320 OP(FH, A, B, C, D, 5, 4, 0xfffa3942);
321 OP(FH, D, A, B, C, 8, 11, 0x8771f681);
322 OP(FH, C, D, A, B, 11, 16, 0x6d9d6122);
323 OP(FH, B, C, D, A, 14, 23, 0xfde5380c);
324 OP(FH, A, B, C, D, 1, 4, 0xa4beea44);
325 OP(FH, D, A, B, C, 4, 11, 0x4bdecfa9);
326 OP(FH, C, D, A, B, 7, 16, 0xf6bb4b60);
327 OP(FH, B, C, D, A, 10, 23, 0xbebfbc70);
328 OP(FH, A, B, C, D, 13, 4, 0x289b7ec6);
329 OP(FH, D, A, B, C, 0, 11, 0xeaa127fa);
330 OP(FH, C, D, A, B, 3, 16, 0xd4ef3085);
331 OP(FH, B, C, D, A, 6, 23, 0x04881d05);
332 OP(FH, A, B, C, D, 9, 4, 0xd9d4d039);
333 OP(FH, D, A, B, C, 12, 11, 0xe6db99e5);
334 OP(FH, C, D, A, B, 15, 16, 0x1fa27cf8);
335 OP(FH, B, C, D, A, 2, 23, 0xc4ac5665);
336 # endif /* MD5_SIZE_VS_SPEED == 1 */
339 # if MD5_SIZE_VS_SPEED == 1
340 for (i = 0; i < 4; i++) {
341 OP(FI, A, B, C, D, (int) (*pp++), 6, *pc++);
342 OP(FI, D, A, B, C, (int) (*pp++), 10, *pc++);
343 OP(FI, C, D, A, B, (int) (*pp++), 15, *pc++);
344 OP(FI, B, C, D, A, (int) (*pp++), 21, *pc++);
347 OP(FI, A, B, C, D, 0, 6, 0xf4292244);
348 OP(FI, D, A, B, C, 7, 10, 0x432aff97);
349 OP(FI, C, D, A, B, 14, 15, 0xab9423a7);
350 OP(FI, B, C, D, A, 5, 21, 0xfc93a039);
351 OP(FI, A, B, C, D, 12, 6, 0x655b59c3);
352 OP(FI, D, A, B, C, 3, 10, 0x8f0ccc92);
353 OP(FI, C, D, A, B, 10, 15, 0xffeff47d);
354 OP(FI, B, C, D, A, 1, 21, 0x85845dd1);
355 OP(FI, A, B, C, D, 8, 6, 0x6fa87e4f);
356 OP(FI, D, A, B, C, 15, 10, 0xfe2ce6e0);
357 OP(FI, C, D, A, B, 6, 15, 0xa3014314);
358 OP(FI, B, C, D, A, 13, 21, 0x4e0811a1);
359 OP(FI, A, B, C, D, 4, 6, 0xf7537e82);
360 OP(FI, D, A, B, C, 11, 10, 0xbd3af235);
361 OP(FI, C, D, A, B, 2, 15, 0x2ad7d2bb);
362 OP(FI, B, C, D, A, 9, 21, 0xeb86d391);
363 # endif /* MD5_SIZE_VS_SPEED == 1 */
364 # endif /* MD5_SIZE_VS_SPEED > 1 */
366 /* Add the starting values of the context. */
372 /* Put checksum in context given as argument. */
379 /* Feed data through a temporary buffer to call md5_hash_aligned_block()
380 * with chunks of data that are 4-byte aligned and a multiple of 64 bytes.
381 * This function's internal buffer remembers previous data until it has 64
382 * bytes worth to pass on. Call md5_end() to flush this buffer. */
384 void md5_hash(const void *buffer, size_t len, md5_ctx_t *ctx)
386 char *buf=(char *)buffer;
388 /* RFC 1321 specifies the possible length of the file up to 2^64 bits,
389 * Here we only track the number of bytes. */
393 // Process all input.
396 int i = 64 - ctx->buflen;
398 // Copy data into aligned buffer.
400 if (i > len) i = len;
401 memcpy(ctx->buffer + ctx->buflen, buf, i);
406 // When buffer fills up, process it.
408 if (ctx->buflen == 64) {
409 md5_hash_block(ctx->buffer, ctx);
415 /* Process the remaining bytes in the buffer and put result from CTX
416 * in first 16 bytes following RESBUF. The result is always in little
417 * endian byte order, so that a byte-wise output yields to the wanted
418 * ASCII representation of the message digest.
420 * IMPORTANT: On some systems it is required that RESBUF is correctly
421 * aligned for a 32 bits value.
423 void *md5_end(void *resbuf, md5_ctx_t *ctx)
425 char *buf = ctx->buffer;
428 /* Pad data to block size. */
430 buf[ctx->buflen++] = 0x80;
431 memset(buf + ctx->buflen, 0, 128 - ctx->buflen);
433 /* Put the 64-bit file length in *bits* at the end of the buffer. */
435 if (ctx->buflen > 56) buf += 64;
436 for (i = 0; i < 8; i++) buf[56 + i] = ctx->total >> (i*8);
438 /* Process last bytes. */
439 if (buf != ctx->buffer) md5_hash_block(ctx->buffer, ctx);
440 md5_hash_block(buf, ctx);
442 /* Put result from CTX in first 16 bytes following RESBUF. The result is
443 * always in little endian byte order, so that a byte-wise output yields
444 * to the wanted ASCII representation of the message digest.
446 * IMPORTANT: On some systems it is required that RESBUF is correctly
447 * aligned for a 32 bits value.
449 ((uint32_t *) resbuf)[0] = SWAP_LE32(ctx->A);
450 ((uint32_t *) resbuf)[1] = SWAP_LE32(ctx->B);
451 ((uint32_t *) resbuf)[2] = SWAP_LE32(ctx->C);
452 ((uint32_t *) resbuf)[3] = SWAP_LE32(ctx->D);