Contents of /trunk/mkinitrd-magellan/busybox/libbb/md5.c
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Wed Aug 18 21:56:57 2010 UTC (14 years, 1 month ago) by niro
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Wed Aug 18 21:56:57 2010 UTC (14 years, 1 month ago) by niro
File MIME type: text/plain
File size: 11853 byte(s)
-updated to busybox-1.17.1
1 | /* vi: set sw=4 ts=4: */ |
2 | /* |
3 | * md5.c - Compute MD5 checksum of strings according to the |
4 | * definition of MD5 in RFC 1321 from April 1992. |
5 | * |
6 | * Written by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1995. |
7 | * |
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 |
12 | * |
13 | * Licensed under the GPL v2 or later, see the file LICENSE in this tarball. |
14 | */ |
15 | |
16 | #include "libbb.h" |
17 | |
18 | /* 0: fastest, 3: smallest */ |
19 | #if CONFIG_MD5_SIZE_VS_SPEED < 0 |
20 | # define MD5_SIZE_VS_SPEED 0 |
21 | #elif CONFIG_MD5_SIZE_VS_SPEED > 3 |
22 | # define MD5_SIZE_VS_SPEED 3 |
23 | #else |
24 | # define MD5_SIZE_VS_SPEED CONFIG_MD5_SIZE_VS_SPEED |
25 | #endif |
26 | |
27 | /* Initialize structure containing state of computation. |
28 | * (RFC 1321, 3.3: Step 3) |
29 | */ |
30 | void FAST_FUNC md5_begin(md5_ctx_t *ctx) |
31 | { |
32 | ctx->A = 0x67452301; |
33 | ctx->B = 0xefcdab89; |
34 | ctx->C = 0x98badcfe; |
35 | ctx->D = 0x10325476; |
36 | ctx->total = 0; |
37 | ctx->buflen = 0; |
38 | } |
39 | |
40 | /* These are the four functions used in the four steps of the MD5 algorithm |
41 | * and defined in the RFC 1321. The first function is a little bit optimized |
42 | * (as found in Colin Plumbs public domain implementation). |
43 | * #define FF(b, c, d) ((b & c) | (~b & d)) |
44 | */ |
45 | #define FF(b, c, d) (d ^ (b & (c ^ d))) |
46 | #define FG(b, c, d) FF(d, b, c) |
47 | #define FH(b, c, d) (b ^ c ^ d) |
48 | #define FI(b, c, d) (c ^ (b | ~d)) |
49 | |
50 | #define rotl32(w, s) (((w) << (s)) | ((w) >> (32 - (s)))) |
51 | |
52 | /* Hash a single block, 64 bytes long and 4-byte aligned. */ |
53 | static void md5_hash_block(const void *buffer, md5_ctx_t *ctx) |
54 | { |
55 | uint32_t correct_words[16]; |
56 | const uint32_t *words = buffer; |
57 | |
58 | #if MD5_SIZE_VS_SPEED > 0 |
59 | static const uint32_t C_array[] = { |
60 | /* round 1 */ |
61 | 0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee, |
62 | 0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501, |
63 | 0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be, |
64 | 0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821, |
65 | /* round 2 */ |
66 | 0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa, |
67 | 0xd62f105d, 0x2441453, 0xd8a1e681, 0xe7d3fbc8, |
68 | 0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed, |
69 | 0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a, |
70 | /* round 3 */ |
71 | 0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c, |
72 | 0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70, |
73 | 0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x4881d05, |
74 | 0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665, |
75 | /* round 4 */ |
76 | 0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039, |
77 | 0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1, |
78 | 0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1, |
79 | 0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391 |
80 | }; |
81 | static const char P_array[] ALIGN1 = { |
82 | # if MD5_SIZE_VS_SPEED > 1 |
83 | 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, /* 1 */ |
84 | # endif |
85 | 1, 6, 11, 0, 5, 10, 15, 4, 9, 14, 3, 8, 13, 2, 7, 12, /* 2 */ |
86 | 5, 8, 11, 14, 1, 4, 7, 10, 13, 0, 3, 6, 9, 12, 15, 2, /* 3 */ |
87 | 0, 7, 14, 5, 12, 3, 10, 1, 8, 15, 6, 13, 4, 11, 2, 9 /* 4 */ |
88 | }; |
89 | # if MD5_SIZE_VS_SPEED > 1 |
90 | static const char S_array[] ALIGN1 = { |
91 | 7, 12, 17, 22, |
92 | 5, 9, 14, 20, |
93 | 4, 11, 16, 23, |
94 | 6, 10, 15, 21 |
95 | }; |
96 | # endif /* MD5_SIZE_VS_SPEED > 1 */ |
97 | #endif |
98 | uint32_t A = ctx->A; |
99 | uint32_t B = ctx->B; |
100 | uint32_t C = ctx->C; |
101 | uint32_t D = ctx->D; |
102 | |
103 | /* Process all bytes in the buffer with 64 bytes in each round of |
104 | the loop. */ |
105 | uint32_t *cwp = correct_words; |
106 | uint32_t A_save = A; |
107 | uint32_t B_save = B; |
108 | uint32_t C_save = C; |
109 | uint32_t D_save = D; |
110 | |
111 | #if MD5_SIZE_VS_SPEED > 1 |
112 | const uint32_t *pc; |
113 | const char *pp; |
114 | const char *ps; |
115 | int i; |
116 | uint32_t temp; |
117 | |
118 | for (i = 0; i < 16; i++) |
119 | cwp[i] = SWAP_LE32(words[i]); |
120 | words += 16; |
121 | |
122 | # if MD5_SIZE_VS_SPEED > 2 |
123 | pc = C_array; |
124 | pp = P_array; |
125 | ps = S_array - 4; |
126 | |
127 | for (i = 0; i < 64; i++) { |
128 | if ((i & 0x0f) == 0) |
129 | ps += 4; |
130 | temp = A; |
131 | switch (i >> 4) { |
132 | case 0: |
133 | temp += FF(B, C, D); |
134 | break; |
135 | case 1: |
136 | temp += FG(B, C, D); |
137 | break; |
138 | case 2: |
139 | temp += FH(B, C, D); |
140 | break; |
141 | case 3: |
142 | temp += FI(B, C, D); |
143 | } |
144 | temp += cwp[(int) (*pp++)] + *pc++; |
145 | temp = rotl32(temp, ps[i & 3]); |
146 | temp += B; |
147 | A = D; |
148 | D = C; |
149 | C = B; |
150 | B = temp; |
151 | } |
152 | # else |
153 | pc = C_array; |
154 | pp = P_array; |
155 | ps = S_array; |
156 | |
157 | for (i = 0; i < 16; i++) { |
158 | temp = A + FF(B, C, D) + cwp[(int) (*pp++)] + *pc++; |
159 | temp = rotl32(temp, ps[i & 3]); |
160 | temp += B; |
161 | A = D; |
162 | D = C; |
163 | C = B; |
164 | B = temp; |
165 | } |
166 | ps += 4; |
167 | for (i = 0; i < 16; i++) { |
168 | temp = A + FG(B, C, D) + cwp[(int) (*pp++)] + *pc++; |
169 | temp = rotl32(temp, ps[i & 3]); |
170 | temp += B; |
171 | A = D; |
172 | D = C; |
173 | C = B; |
174 | B = temp; |
175 | } |
176 | ps += 4; |
177 | for (i = 0; i < 16; i++) { |
178 | temp = A + FH(B, C, D) + cwp[(int) (*pp++)] + *pc++; |
179 | temp = rotl32(temp, ps[i & 3]); |
180 | temp += B; |
181 | A = D; |
182 | D = C; |
183 | C = B; |
184 | B = temp; |
185 | } |
186 | ps += 4; |
187 | for (i = 0; i < 16; i++) { |
188 | temp = A + FI(B, C, D) + cwp[(int) (*pp++)] + *pc++; |
189 | temp = rotl32(temp, ps[i & 3]); |
190 | temp += B; |
191 | A = D; |
192 | D = C; |
193 | C = B; |
194 | B = temp; |
195 | } |
196 | |
197 | # endif /* MD5_SIZE_VS_SPEED > 2 */ |
198 | #else |
199 | /* First round: using the given function, the context and a constant |
200 | the next context is computed. Because the algorithms processing |
201 | unit is a 32-bit word and it is determined to work on words in |
202 | little endian byte order we perhaps have to change the byte order |
203 | before the computation. To reduce the work for the next steps |
204 | we store the swapped words in the array CORRECT_WORDS. */ |
205 | # define OP(a, b, c, d, s, T) \ |
206 | do { \ |
207 | a += FF(b, c, d) + (*cwp++ = SWAP_LE32(*words)) + T; \ |
208 | ++words; \ |
209 | a = rotl32(a, s); \ |
210 | a += b; \ |
211 | } while (0) |
212 | |
213 | /* Before we start, one word to the strange constants. |
214 | They are defined in RFC 1321 as |
215 | T[i] = (int)(4294967296.0 * fabs(sin(i))), i=1..64 |
216 | */ |
217 | |
218 | # if MD5_SIZE_VS_SPEED == 1 |
219 | const uint32_t *pc; |
220 | const char *pp; |
221 | int i; |
222 | # endif /* MD5_SIZE_VS_SPEED */ |
223 | |
224 | /* Round 1. */ |
225 | # if MD5_SIZE_VS_SPEED == 1 |
226 | pc = C_array; |
227 | for (i = 0; i < 4; i++) { |
228 | OP(A, B, C, D, 7, *pc++); |
229 | OP(D, A, B, C, 12, *pc++); |
230 | OP(C, D, A, B, 17, *pc++); |
231 | OP(B, C, D, A, 22, *pc++); |
232 | } |
233 | # else |
234 | OP(A, B, C, D, 7, 0xd76aa478); |
235 | OP(D, A, B, C, 12, 0xe8c7b756); |
236 | OP(C, D, A, B, 17, 0x242070db); |
237 | OP(B, C, D, A, 22, 0xc1bdceee); |
238 | OP(A, B, C, D, 7, 0xf57c0faf); |
239 | OP(D, A, B, C, 12, 0x4787c62a); |
240 | OP(C, D, A, B, 17, 0xa8304613); |
241 | OP(B, C, D, A, 22, 0xfd469501); |
242 | OP(A, B, C, D, 7, 0x698098d8); |
243 | OP(D, A, B, C, 12, 0x8b44f7af); |
244 | OP(C, D, A, B, 17, 0xffff5bb1); |
245 | OP(B, C, D, A, 22, 0x895cd7be); |
246 | OP(A, B, C, D, 7, 0x6b901122); |
247 | OP(D, A, B, C, 12, 0xfd987193); |
248 | OP(C, D, A, B, 17, 0xa679438e); |
249 | OP(B, C, D, A, 22, 0x49b40821); |
250 | # endif /* MD5_SIZE_VS_SPEED == 1 */ |
251 | |
252 | /* For the second to fourth round we have the possibly swapped words |
253 | in CORRECT_WORDS. Redefine the macro to take an additional first |
254 | argument specifying the function to use. */ |
255 | # undef OP |
256 | # define OP(f, a, b, c, d, k, s, T) \ |
257 | do { \ |
258 | a += f(b, c, d) + correct_words[k] + T; \ |
259 | a = rotl32(a, s); \ |
260 | a += b; \ |
261 | } while (0) |
262 | |
263 | /* Round 2. */ |
264 | # if MD5_SIZE_VS_SPEED == 1 |
265 | pp = P_array; |
266 | for (i = 0; i < 4; i++) { |
267 | OP(FG, A, B, C, D, (int) (*pp++), 5, *pc++); |
268 | OP(FG, D, A, B, C, (int) (*pp++), 9, *pc++); |
269 | OP(FG, C, D, A, B, (int) (*pp++), 14, *pc++); |
270 | OP(FG, B, C, D, A, (int) (*pp++), 20, *pc++); |
271 | } |
272 | # else |
273 | OP(FG, A, B, C, D, 1, 5, 0xf61e2562); |
274 | OP(FG, D, A, B, C, 6, 9, 0xc040b340); |
275 | OP(FG, C, D, A, B, 11, 14, 0x265e5a51); |
276 | OP(FG, B, C, D, A, 0, 20, 0xe9b6c7aa); |
277 | OP(FG, A, B, C, D, 5, 5, 0xd62f105d); |
278 | OP(FG, D, A, B, C, 10, 9, 0x02441453); |
279 | OP(FG, C, D, A, B, 15, 14, 0xd8a1e681); |
280 | OP(FG, B, C, D, A, 4, 20, 0xe7d3fbc8); |
281 | OP(FG, A, B, C, D, 9, 5, 0x21e1cde6); |
282 | OP(FG, D, A, B, C, 14, 9, 0xc33707d6); |
283 | OP(FG, C, D, A, B, 3, 14, 0xf4d50d87); |
284 | OP(FG, B, C, D, A, 8, 20, 0x455a14ed); |
285 | OP(FG, A, B, C, D, 13, 5, 0xa9e3e905); |
286 | OP(FG, D, A, B, C, 2, 9, 0xfcefa3f8); |
287 | OP(FG, C, D, A, B, 7, 14, 0x676f02d9); |
288 | OP(FG, B, C, D, A, 12, 20, 0x8d2a4c8a); |
289 | # endif /* MD5_SIZE_VS_SPEED == 1 */ |
290 | |
291 | /* Round 3. */ |
292 | # if MD5_SIZE_VS_SPEED == 1 |
293 | for (i = 0; i < 4; i++) { |
294 | OP(FH, A, B, C, D, (int) (*pp++), 4, *pc++); |
295 | OP(FH, D, A, B, C, (int) (*pp++), 11, *pc++); |
296 | OP(FH, C, D, A, B, (int) (*pp++), 16, *pc++); |
297 | OP(FH, B, C, D, A, (int) (*pp++), 23, *pc++); |
298 | } |
299 | # else |
300 | OP(FH, A, B, C, D, 5, 4, 0xfffa3942); |
301 | OP(FH, D, A, B, C, 8, 11, 0x8771f681); |
302 | OP(FH, C, D, A, B, 11, 16, 0x6d9d6122); |
303 | OP(FH, B, C, D, A, 14, 23, 0xfde5380c); |
304 | OP(FH, A, B, C, D, 1, 4, 0xa4beea44); |
305 | OP(FH, D, A, B, C, 4, 11, 0x4bdecfa9); |
306 | OP(FH, C, D, A, B, 7, 16, 0xf6bb4b60); |
307 | OP(FH, B, C, D, A, 10, 23, 0xbebfbc70); |
308 | OP(FH, A, B, C, D, 13, 4, 0x289b7ec6); |
309 | OP(FH, D, A, B, C, 0, 11, 0xeaa127fa); |
310 | OP(FH, C, D, A, B, 3, 16, 0xd4ef3085); |
311 | OP(FH, B, C, D, A, 6, 23, 0x04881d05); |
312 | OP(FH, A, B, C, D, 9, 4, 0xd9d4d039); |
313 | OP(FH, D, A, B, C, 12, 11, 0xe6db99e5); |
314 | OP(FH, C, D, A, B, 15, 16, 0x1fa27cf8); |
315 | OP(FH, B, C, D, A, 2, 23, 0xc4ac5665); |
316 | # endif /* MD5_SIZE_VS_SPEED == 1 */ |
317 | |
318 | /* Round 4. */ |
319 | # if MD5_SIZE_VS_SPEED == 1 |
320 | for (i = 0; i < 4; i++) { |
321 | OP(FI, A, B, C, D, (int) (*pp++), 6, *pc++); |
322 | OP(FI, D, A, B, C, (int) (*pp++), 10, *pc++); |
323 | OP(FI, C, D, A, B, (int) (*pp++), 15, *pc++); |
324 | OP(FI, B, C, D, A, (int) (*pp++), 21, *pc++); |
325 | } |
326 | # else |
327 | OP(FI, A, B, C, D, 0, 6, 0xf4292244); |
328 | OP(FI, D, A, B, C, 7, 10, 0x432aff97); |
329 | OP(FI, C, D, A, B, 14, 15, 0xab9423a7); |
330 | OP(FI, B, C, D, A, 5, 21, 0xfc93a039); |
331 | OP(FI, A, B, C, D, 12, 6, 0x655b59c3); |
332 | OP(FI, D, A, B, C, 3, 10, 0x8f0ccc92); |
333 | OP(FI, C, D, A, B, 10, 15, 0xffeff47d); |
334 | OP(FI, B, C, D, A, 1, 21, 0x85845dd1); |
335 | OP(FI, A, B, C, D, 8, 6, 0x6fa87e4f); |
336 | OP(FI, D, A, B, C, 15, 10, 0xfe2ce6e0); |
337 | OP(FI, C, D, A, B, 6, 15, 0xa3014314); |
338 | OP(FI, B, C, D, A, 13, 21, 0x4e0811a1); |
339 | OP(FI, A, B, C, D, 4, 6, 0xf7537e82); |
340 | OP(FI, D, A, B, C, 11, 10, 0xbd3af235); |
341 | OP(FI, C, D, A, B, 2, 15, 0x2ad7d2bb); |
342 | OP(FI, B, C, D, A, 9, 21, 0xeb86d391); |
343 | # endif /* MD5_SIZE_VS_SPEED == 1 */ |
344 | #endif /* MD5_SIZE_VS_SPEED > 1 */ |
345 | |
346 | /* Add the starting values of the context. */ |
347 | A += A_save; |
348 | B += B_save; |
349 | C += C_save; |
350 | D += D_save; |
351 | |
352 | /* Put checksum in context given as argument. */ |
353 | ctx->A = A; |
354 | ctx->B = B; |
355 | ctx->C = C; |
356 | ctx->D = D; |
357 | } |
358 | |
359 | /* Feed data through a temporary buffer to call md5_hash_aligned_block() |
360 | * with chunks of data that are 4-byte aligned and a multiple of 64 bytes. |
361 | * This function's internal buffer remembers previous data until it has 64 |
362 | * bytes worth to pass on. Call md5_end() to flush this buffer. */ |
363 | void FAST_FUNC md5_hash(const void *buffer, size_t len, md5_ctx_t *ctx) |
364 | { |
365 | char *buf = (char *)buffer; |
366 | |
367 | /* RFC 1321 specifies the possible length of the file up to 2^64 bits, |
368 | * Here we only track the number of bytes. */ |
369 | ctx->total += len; |
370 | |
371 | /* Process all input. */ |
372 | while (len) { |
373 | unsigned i = 64 - ctx->buflen; |
374 | |
375 | /* Copy data into aligned buffer. */ |
376 | if (i > len) |
377 | i = len; |
378 | memcpy(ctx->buffer + ctx->buflen, buf, i); |
379 | len -= i; |
380 | ctx->buflen += i; |
381 | buf += i; |
382 | |
383 | /* When buffer fills up, process it. */ |
384 | if (ctx->buflen == 64) { |
385 | md5_hash_block(ctx->buffer, ctx); |
386 | ctx->buflen = 0; |
387 | } |
388 | } |
389 | } |
390 | |
391 | /* Process the remaining bytes in the buffer and put result from CTX |
392 | * in first 16 bytes following RESBUF. The result is always in little |
393 | * endian byte order, so that a byte-wise output yields to the wanted |
394 | * ASCII representation of the message digest. |
395 | */ |
396 | void FAST_FUNC md5_end(void *resbuf, md5_ctx_t *ctx) |
397 | { |
398 | char *buf = ctx->buffer; |
399 | int i; |
400 | |
401 | /* Pad data to block size. */ |
402 | buf[ctx->buflen++] = 0x80; |
403 | memset(buf + ctx->buflen, 0, 128 - ctx->buflen); |
404 | |
405 | /* Put the 64-bit file length in *bits* at the end of the buffer. */ |
406 | ctx->total <<= 3; |
407 | if (ctx->buflen > 56) |
408 | buf += 64; |
409 | for (i = 0; i < 8; i++) |
410 | buf[56 + i] = ctx->total >> (i*8); |
411 | |
412 | /* Process last bytes. */ |
413 | if (buf != ctx->buffer) |
414 | md5_hash_block(ctx->buffer, ctx); |
415 | md5_hash_block(buf, ctx); |
416 | |
417 | /* The MD5 result is in little endian byte order. |
418 | * We (ab)use the fact that A-D are consecutive in memory. |
419 | */ |
420 | #if BB_BIG_ENDIAN |
421 | ctx->A = SWAP_LE32(ctx->A); |
422 | ctx->B = SWAP_LE32(ctx->B); |
423 | ctx->C = SWAP_LE32(ctx->C); |
424 | ctx->D = SWAP_LE32(ctx->D); |
425 | #endif |
426 | memcpy(resbuf, &ctx->A, sizeof(ctx->A) * 4); |
427 | } |