Commit | Line | Data |
---|---|---|
693c4692 GM |
1 | /* Functions to compute MD5 message digest of files or memory blocks. |
2 | according to the definition of MD5 in RFC 1321 from April 1992. | |
429ab54e GM |
3 | Copyright (C) 1995, 1996, 1997, 1999, 2000, 2001, 2002, 2003, 2004, |
4 | 2005, 2006, 2007 Free Software Foundation, Inc. | |
4cec53bf GM |
5 | |
6 | This file is part of the GNU C Library. | |
693c4692 GM |
7 | |
8 | The GNU C Library is free software; you can redistribute it and/or | |
423a1f3c | 9 | modify it under the terms of the GNU General Public License as |
693c4692 GM |
10 | published by the Free Software Foundation; either version 2 of the |
11 | License, or (at your option) any later version. | |
12 | ||
13 | The GNU C Library is distributed in the hope that it will be useful, | |
14 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
423a1f3c | 16 | General Public License for more details. |
693c4692 | 17 | |
4cec53bf GM |
18 | You should have received a copy of the GNU General Public License |
19 | along with the GNU C Library; see the file COPYING. If not, write to the | |
20 | Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, | |
4fc5845f | 21 | Boston, MA 02110-1301, USA. */ |
693c4692 GM |
22 | |
23 | /* Written by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1995. */ | |
24 | ||
25 | #ifdef HAVE_CONFIG_H | |
26 | # include <config.h> | |
27 | #endif | |
28 | ||
29 | #include <sys/types.h> | |
30 | ||
31 | #if STDC_HEADERS || defined _LIBC | |
32 | # include <stdlib.h> | |
33 | # include <string.h> | |
34 | #else | |
35 | # ifndef HAVE_MEMCPY | |
36 | # define memcpy(d, s, n) bcopy ((s), (d), (n)) | |
37 | # endif | |
38 | #endif | |
39 | ||
693c4692 GM |
40 | #ifdef _LIBC |
41 | # include <endian.h> | |
42 | # if __BYTE_ORDER == __BIG_ENDIAN | |
1c0e6fa4 | 43 | # define WORDS_BIG_ENDIAN 1 |
693c4692 GM |
44 | # endif |
45 | /* We need to keep the namespace clean so define the MD5 function | |
46 | protected using leading __ . */ | |
47 | # define md5_init_ctx __md5_init_ctx | |
48 | # define md5_process_block __md5_process_block | |
49 | # define md5_process_bytes __md5_process_bytes | |
50 | # define md5_finish_ctx __md5_finish_ctx | |
51 | # define md5_read_ctx __md5_read_ctx | |
52 | # define md5_stream __md5_stream | |
53 | # define md5_buffer __md5_buffer | |
54 | #endif | |
55 | ||
c9fddc6f JR |
56 | #include "md5.h" |
57 | ||
1c0e6fa4 | 58 | #ifdef WORDS_BIG_ENDIAN |
693c4692 GM |
59 | # define SWAP(n) \ |
60 | (((n) << 24) | (((n) & 0xff00) << 8) | (((n) >> 8) & 0xff00) | ((n) >> 24)) | |
61 | #else | |
62 | # define SWAP(n) (n) | |
63 | #endif | |
64 | ||
65 | ||
66 | /* This array contains the bytes used to pad the buffer to the next | |
67 | 64-byte boundary. (RFC 1321, 3.1: Step 1) */ | |
68 | static const unsigned char fillbuf[64] = { 0x80, 0 /* , 0, 0, ... */ }; | |
69 | ||
70 | ||
71 | /* Initialize structure containing state of computation. | |
72 | (RFC 1321, 3.3: Step 3) */ | |
73 | void | |
74 | md5_init_ctx (ctx) | |
75 | struct md5_ctx *ctx; | |
76 | { | |
77 | ctx->A = 0x67452301; | |
78 | ctx->B = 0xefcdab89; | |
79 | ctx->C = 0x98badcfe; | |
80 | ctx->D = 0x10325476; | |
81 | ||
82 | ctx->total[0] = ctx->total[1] = 0; | |
83 | ctx->buflen = 0; | |
84 | } | |
85 | ||
86 | /* Put result from CTX in first 16 bytes following RESBUF. The result | |
87 | must be in little endian byte order. | |
88 | ||
89 | IMPORTANT: On some systems it is required that RESBUF is correctly | |
90 | aligned for a 32 bits value. */ | |
91 | void * | |
92 | md5_read_ctx (ctx, resbuf) | |
93 | const struct md5_ctx *ctx; | |
94 | void *resbuf; | |
95 | { | |
96 | ((md5_uint32 *) resbuf)[0] = SWAP (ctx->A); | |
97 | ((md5_uint32 *) resbuf)[1] = SWAP (ctx->B); | |
98 | ((md5_uint32 *) resbuf)[2] = SWAP (ctx->C); | |
99 | ((md5_uint32 *) resbuf)[3] = SWAP (ctx->D); | |
100 | ||
101 | return resbuf; | |
102 | } | |
103 | ||
104 | /* Process the remaining bytes in the internal buffer and the usual | |
105 | prolog according to the standard and write the result to RESBUF. | |
106 | ||
107 | IMPORTANT: On some systems it is required that RESBUF is correctly | |
108 | aligned for a 32 bits value. */ | |
109 | void * | |
110 | md5_finish_ctx (ctx, resbuf) | |
111 | struct md5_ctx *ctx; | |
112 | void *resbuf; | |
113 | { | |
114 | /* Take yet unprocessed bytes into account. */ | |
115 | md5_uint32 bytes = ctx->buflen; | |
116 | size_t pad; | |
117 | ||
118 | /* Now count remaining bytes. */ | |
119 | ctx->total[0] += bytes; | |
120 | if (ctx->total[0] < bytes) | |
121 | ++ctx->total[1]; | |
122 | ||
123 | pad = bytes >= 56 ? 64 + 56 - bytes : 56 - bytes; | |
124 | memcpy (&ctx->buffer[bytes], fillbuf, pad); | |
125 | ||
126 | /* Put the 64-bit file length in *bits* at the end of the buffer. */ | |
127 | *(md5_uint32 *) &ctx->buffer[bytes + pad] = SWAP (ctx->total[0] << 3); | |
128 | *(md5_uint32 *) &ctx->buffer[bytes + pad + 4] = SWAP ((ctx->total[1] << 3) | | |
129 | (ctx->total[0] >> 29)); | |
130 | ||
131 | /* Process last bytes. */ | |
132 | md5_process_block (ctx->buffer, bytes + pad + 8, ctx); | |
133 | ||
134 | return md5_read_ctx (ctx, resbuf); | |
135 | } | |
136 | ||
137 | /* Compute MD5 message digest for bytes read from STREAM. The | |
138 | resulting message digest number will be written into the 16 bytes | |
139 | beginning at RESBLOCK. */ | |
140 | int | |
141 | md5_stream (stream, resblock) | |
142 | FILE *stream; | |
143 | void *resblock; | |
144 | { | |
145 | /* Important: BLOCKSIZE must be a multiple of 64. */ | |
146 | #define BLOCKSIZE 4096 | |
147 | struct md5_ctx ctx; | |
148 | char buffer[BLOCKSIZE + 72]; | |
149 | size_t sum; | |
150 | ||
151 | /* Initialize the computation context. */ | |
152 | md5_init_ctx (&ctx); | |
153 | ||
154 | /* Iterate over full file contents. */ | |
155 | while (1) | |
156 | { | |
157 | /* We read the file in blocks of BLOCKSIZE bytes. One call of the | |
158 | computation function processes the whole buffer so that with the | |
159 | next round of the loop another block can be read. */ | |
160 | size_t n; | |
161 | sum = 0; | |
162 | ||
163 | /* Read block. Take care for partial reads. */ | |
164 | do | |
165 | { | |
166 | n = fread (buffer + sum, 1, BLOCKSIZE - sum, stream); | |
167 | ||
168 | sum += n; | |
169 | } | |
170 | while (sum < BLOCKSIZE && n != 0); | |
171 | if (n == 0 && ferror (stream)) | |
172 | return 1; | |
173 | ||
174 | /* If end of file is reached, end the loop. */ | |
175 | if (n == 0) | |
176 | break; | |
177 | ||
178 | /* Process buffer with BLOCKSIZE bytes. Note that | |
179 | BLOCKSIZE % 64 == 0 | |
180 | */ | |
181 | md5_process_block (buffer, BLOCKSIZE, &ctx); | |
182 | } | |
183 | ||
184 | /* Add the last bytes if necessary. */ | |
185 | if (sum > 0) | |
186 | md5_process_bytes (buffer, sum, &ctx); | |
187 | ||
188 | /* Construct result in desired memory. */ | |
189 | md5_finish_ctx (&ctx, resblock); | |
190 | return 0; | |
191 | } | |
192 | ||
193 | /* Compute MD5 message digest for LEN bytes beginning at BUFFER. The | |
194 | result is always in little endian byte order, so that a byte-wise | |
195 | output yields to the wanted ASCII representation of the message | |
196 | digest. */ | |
197 | void * | |
198 | md5_buffer (buffer, len, resblock) | |
199 | const char *buffer; | |
200 | size_t len; | |
201 | void *resblock; | |
202 | { | |
203 | struct md5_ctx ctx; | |
204 | ||
205 | /* Initialize the computation context. */ | |
206 | md5_init_ctx (&ctx); | |
207 | ||
208 | /* Process whole buffer but last len % 64 bytes. */ | |
209 | md5_process_bytes (buffer, len, &ctx); | |
210 | ||
211 | /* Put result in desired memory area. */ | |
212 | return md5_finish_ctx (&ctx, resblock); | |
213 | } | |
214 | ||
215 | ||
216 | void | |
217 | md5_process_bytes (buffer, len, ctx) | |
218 | const void *buffer; | |
219 | size_t len; | |
220 | struct md5_ctx *ctx; | |
221 | { | |
11753d04 | 222 | /* const void aligned_buffer = buffer; */ |
693c4692 GM |
223 | |
224 | /* When we already have some bits in our internal buffer concatenate | |
225 | both inputs first. */ | |
226 | if (ctx->buflen != 0) | |
227 | { | |
228 | size_t left_over = ctx->buflen; | |
229 | size_t add = 128 - left_over > len ? len : 128 - left_over; | |
230 | ||
231 | /* Only put full words in the buffer. */ | |
232 | add -= add % __alignof__ (md5_uint32); | |
233 | ||
234 | memcpy (&ctx->buffer[left_over], buffer, add); | |
235 | ctx->buflen += add; | |
236 | ||
237 | if (ctx->buflen > 64) | |
238 | { | |
239 | md5_process_block (ctx->buffer, ctx->buflen & ~63, ctx); | |
240 | ||
241 | ctx->buflen &= 63; | |
242 | /* The regions in the following copy operation cannot overlap. */ | |
243 | memcpy (ctx->buffer, &ctx->buffer[(left_over + add) & ~63], | |
244 | ctx->buflen); | |
245 | } | |
246 | ||
247 | buffer = (const char *) buffer + add; | |
248 | len -= add; | |
249 | } | |
250 | ||
251 | /* Process available complete blocks. */ | |
252 | if (len > 64) | |
253 | { | |
254 | md5_process_block (buffer, len & ~63, ctx); | |
255 | buffer = (const char *) buffer + (len & ~63); | |
256 | len &= 63; | |
257 | } | |
258 | ||
259 | /* Move remaining bytes in internal buffer. */ | |
260 | if (len > 0) | |
261 | { | |
262 | size_t left_over = ctx->buflen; | |
263 | ||
264 | memcpy (&ctx->buffer[left_over], buffer, len); | |
265 | left_over += len; | |
266 | if (left_over >= 64) | |
267 | { | |
268 | md5_process_block (ctx->buffer, 64, ctx); | |
269 | left_over -= 64; | |
270 | memcpy (ctx->buffer, &ctx->buffer[64], left_over); | |
271 | } | |
272 | ctx->buflen = left_over; | |
273 | } | |
274 | } | |
275 | ||
276 | ||
277 | /* These are the four functions used in the four steps of the MD5 algorithm | |
278 | and defined in the RFC 1321. The first function is a little bit optimized | |
279 | (as found in Colin Plumbs public domain implementation). */ | |
280 | /* #define FF(b, c, d) ((b & c) | (~b & d)) */ | |
281 | #define FF(b, c, d) (d ^ (b & (c ^ d))) | |
282 | #define FG(b, c, d) FF (d, b, c) | |
283 | #define FH(b, c, d) (b ^ c ^ d) | |
284 | #define FI(b, c, d) (c ^ (b | ~d)) | |
285 | ||
286 | /* Process LEN bytes of BUFFER, accumulating context into CTX. | |
287 | It is assumed that LEN % 64 == 0. */ | |
288 | ||
289 | void | |
290 | md5_process_block (buffer, len, ctx) | |
291 | const void *buffer; | |
292 | size_t len; | |
293 | struct md5_ctx *ctx; | |
294 | { | |
295 | md5_uint32 correct_words[16]; | |
296 | const md5_uint32 *words = buffer; | |
297 | size_t nwords = len / sizeof (md5_uint32); | |
298 | const md5_uint32 *endp = words + nwords; | |
299 | md5_uint32 A = ctx->A; | |
300 | md5_uint32 B = ctx->B; | |
301 | md5_uint32 C = ctx->C; | |
302 | md5_uint32 D = ctx->D; | |
303 | ||
304 | /* First increment the byte count. RFC 1321 specifies the possible | |
305 | length of the file up to 2^64 bits. Here we only compute the | |
306 | number of bytes. Do a double word increment. */ | |
307 | ctx->total[0] += len; | |
308 | if (ctx->total[0] < len) | |
309 | ++ctx->total[1]; | |
310 | ||
311 | /* Process all bytes in the buffer with 64 bytes in each round of | |
312 | the loop. */ | |
313 | while (words < endp) | |
314 | { | |
315 | md5_uint32 *cwp = correct_words; | |
316 | md5_uint32 A_save = A; | |
317 | md5_uint32 B_save = B; | |
318 | md5_uint32 C_save = C; | |
319 | md5_uint32 D_save = D; | |
320 | ||
321 | /* First round: using the given function, the context and a constant | |
322 | the next context is computed. Because the algorithms processing | |
323 | unit is a 32-bit word and it is determined to work on words in | |
324 | little endian byte order we perhaps have to change the byte order | |
325 | before the computation. To reduce the work for the next steps | |
326 | we store the swapped words in the array CORRECT_WORDS. */ | |
327 | ||
328 | #define OP(a, b, c, d, s, T) \ | |
329 | do \ | |
330 | { \ | |
331 | a += FF (b, c, d) + (*cwp++ = SWAP (*words)) + T; \ | |
332 | ++words; \ | |
333 | CYCLIC (a, s); \ | |
334 | a += b; \ | |
335 | } \ | |
336 | while (0) | |
337 | ||
338 | /* It is unfortunate that C does not provide an operator for | |
339 | cyclic rotation. Hope the C compiler is smart enough. */ | |
340 | #define CYCLIC(w, s) (w = (w << s) | (w >> (32 - s))) | |
341 | ||
342 | /* Before we start, one word to the strange constants. | |
343 | They are defined in RFC 1321 as | |
344 | ||
345 | T[i] = (int) (4294967296.0 * fabs (sin (i))), i=1..64 | |
346 | */ | |
347 | ||
348 | /* Round 1. */ | |
349 | OP (A, B, C, D, 7, 0xd76aa478); | |
350 | OP (D, A, B, C, 12, 0xe8c7b756); | |
351 | OP (C, D, A, B, 17, 0x242070db); | |
352 | OP (B, C, D, A, 22, 0xc1bdceee); | |
353 | OP (A, B, C, D, 7, 0xf57c0faf); | |
354 | OP (D, A, B, C, 12, 0x4787c62a); | |
355 | OP (C, D, A, B, 17, 0xa8304613); | |
356 | OP (B, C, D, A, 22, 0xfd469501); | |
357 | OP (A, B, C, D, 7, 0x698098d8); | |
358 | OP (D, A, B, C, 12, 0x8b44f7af); | |
359 | OP (C, D, A, B, 17, 0xffff5bb1); | |
360 | OP (B, C, D, A, 22, 0x895cd7be); | |
361 | OP (A, B, C, D, 7, 0x6b901122); | |
362 | OP (D, A, B, C, 12, 0xfd987193); | |
363 | OP (C, D, A, B, 17, 0xa679438e); | |
364 | OP (B, C, D, A, 22, 0x49b40821); | |
365 | ||
366 | /* For the second to fourth round we have the possibly swapped words | |
367 | in CORRECT_WORDS. Redefine the macro to take an additional first | |
368 | argument specifying the function to use. */ | |
369 | #undef OP | |
370 | #define OP(f, a, b, c, d, k, s, T) \ | |
371 | do \ | |
372 | { \ | |
373 | a += f (b, c, d) + correct_words[k] + T; \ | |
374 | CYCLIC (a, s); \ | |
375 | a += b; \ | |
376 | } \ | |
377 | while (0) | |
378 | ||
379 | /* Round 2. */ | |
380 | OP (FG, A, B, C, D, 1, 5, 0xf61e2562); | |
381 | OP (FG, D, A, B, C, 6, 9, 0xc040b340); | |
382 | OP (FG, C, D, A, B, 11, 14, 0x265e5a51); | |
383 | OP (FG, B, C, D, A, 0, 20, 0xe9b6c7aa); | |
384 | OP (FG, A, B, C, D, 5, 5, 0xd62f105d); | |
385 | OP (FG, D, A, B, C, 10, 9, 0x02441453); | |
386 | OP (FG, C, D, A, B, 15, 14, 0xd8a1e681); | |
387 | OP (FG, B, C, D, A, 4, 20, 0xe7d3fbc8); | |
388 | OP (FG, A, B, C, D, 9, 5, 0x21e1cde6); | |
389 | OP (FG, D, A, B, C, 14, 9, 0xc33707d6); | |
390 | OP (FG, C, D, A, B, 3, 14, 0xf4d50d87); | |
391 | OP (FG, B, C, D, A, 8, 20, 0x455a14ed); | |
392 | OP (FG, A, B, C, D, 13, 5, 0xa9e3e905); | |
393 | OP (FG, D, A, B, C, 2, 9, 0xfcefa3f8); | |
394 | OP (FG, C, D, A, B, 7, 14, 0x676f02d9); | |
395 | OP (FG, B, C, D, A, 12, 20, 0x8d2a4c8a); | |
396 | ||
397 | /* Round 3. */ | |
398 | OP (FH, A, B, C, D, 5, 4, 0xfffa3942); | |
399 | OP (FH, D, A, B, C, 8, 11, 0x8771f681); | |
400 | OP (FH, C, D, A, B, 11, 16, 0x6d9d6122); | |
401 | OP (FH, B, C, D, A, 14, 23, 0xfde5380c); | |
402 | OP (FH, A, B, C, D, 1, 4, 0xa4beea44); | |
403 | OP (FH, D, A, B, C, 4, 11, 0x4bdecfa9); | |
404 | OP (FH, C, D, A, B, 7, 16, 0xf6bb4b60); | |
405 | OP (FH, B, C, D, A, 10, 23, 0xbebfbc70); | |
406 | OP (FH, A, B, C, D, 13, 4, 0x289b7ec6); | |
407 | OP (FH, D, A, B, C, 0, 11, 0xeaa127fa); | |
408 | OP (FH, C, D, A, B, 3, 16, 0xd4ef3085); | |
409 | OP (FH, B, C, D, A, 6, 23, 0x04881d05); | |
410 | OP (FH, A, B, C, D, 9, 4, 0xd9d4d039); | |
411 | OP (FH, D, A, B, C, 12, 11, 0xe6db99e5); | |
412 | OP (FH, C, D, A, B, 15, 16, 0x1fa27cf8); | |
413 | OP (FH, B, C, D, A, 2, 23, 0xc4ac5665); | |
414 | ||
415 | /* Round 4. */ | |
416 | OP (FI, A, B, C, D, 0, 6, 0xf4292244); | |
417 | OP (FI, D, A, B, C, 7, 10, 0x432aff97); | |
418 | OP (FI, C, D, A, B, 14, 15, 0xab9423a7); | |
419 | OP (FI, B, C, D, A, 5, 21, 0xfc93a039); | |
420 | OP (FI, A, B, C, D, 12, 6, 0x655b59c3); | |
421 | OP (FI, D, A, B, C, 3, 10, 0x8f0ccc92); | |
422 | OP (FI, C, D, A, B, 10, 15, 0xffeff47d); | |
423 | OP (FI, B, C, D, A, 1, 21, 0x85845dd1); | |
424 | OP (FI, A, B, C, D, 8, 6, 0x6fa87e4f); | |
425 | OP (FI, D, A, B, C, 15, 10, 0xfe2ce6e0); | |
426 | OP (FI, C, D, A, B, 6, 15, 0xa3014314); | |
427 | OP (FI, B, C, D, A, 13, 21, 0x4e0811a1); | |
428 | OP (FI, A, B, C, D, 4, 6, 0xf7537e82); | |
429 | OP (FI, D, A, B, C, 11, 10, 0xbd3af235); | |
430 | OP (FI, C, D, A, B, 2, 15, 0x2ad7d2bb); | |
431 | OP (FI, B, C, D, A, 9, 21, 0xeb86d391); | |
432 | ||
433 | /* Add the starting values of the context. */ | |
434 | A += A_save; | |
435 | B += B_save; | |
436 | C += C_save; | |
437 | D += D_save; | |
438 | } | |
439 | ||
440 | /* Put checksum in context given as argument. */ | |
441 | ctx->A = A; | |
442 | ctx->B = B; | |
443 | ctx->C = C; | |
444 | ctx->D = D; | |
445 | } | |
ab5796a9 MB |
446 | |
447 | /* arch-tag: 60084f04-b434-42cb-9d2b-e91df01f4325 | |
448 | (do not change this comment) */ |