Mercurial > hg > CbC > CbC_gcc

comparison libiberty/sha1.c @ 0:a06113de4d67

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
first commit
author kent <kent@cr.ie.u-ryukyu.ac.jp>
date Fri, 17 Jul 2009 14:47:48 +0900
parents
children 04ced10e8804
comparison
equal deleted inserted replaced
-1:000000000000 0:a06113de4d67
1 /* sha1.c - Functions to compute SHA1 message digest of files or
2 memory blocks according to the NIST specification FIPS-180-1.
3
4 Copyright (C) 2000, 2001, 2003, 2004, 2005, 2006, 2008 Free Software
5 Foundation, Inc.
6
7 This program is free software; you can redistribute it and/or modify it
8 under the terms of the GNU General Public License as published by the
9 Free Software Foundation; either version 2, or (at your option) any
10 later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software Foundation,
19 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
20
21 /* Written by Scott G. Miller
22 Credits:
23 Robert Klep <robert@ilse.nl> -- Expansion function fix
24 */
25
26 #include <config.h>
27
28 #include "sha1.h"
29
30 #include <stddef.h>
31 #include <string.h>
32
33 #if USE_UNLOCKED_IO
34 # include "unlocked-io.h"
35 #endif
36
37 #ifdef WORDS_BIGENDIAN
38 # define SWAP(n) (n)
39 #else
40 # define SWAP(n) \
41 (((n) << 24) | (((n) & 0xff00) << 8) | (((n) >> 8) & 0xff00) | ((n) >> 24))
42 #endif
43
44 #define BLOCKSIZE 4096
45 #if BLOCKSIZE % 64 != 0
46 # error "invalid BLOCKSIZE"
47 #endif
48
49 /* This array contains the bytes used to pad the buffer to the next
50 64-byte boundary. (RFC 1321, 3.1: Step 1) */
51 static const unsigned char fillbuf[64] = { 0x80, 0 /* , 0, 0, ... */ };
52
53
54 /* Take a pointer to a 160 bit block of data (five 32 bit ints) and
55 initialize it to the start constants of the SHA1 algorithm. This
56 must be called before using hash in the call to sha1_hash. */
57 void
58 sha1_init_ctx (struct sha1_ctx *ctx)
59 {
60 ctx->A = 0x67452301;
61 ctx->B = 0xefcdab89;
62 ctx->C = 0x98badcfe;
63 ctx->D = 0x10325476;
64 ctx->E = 0xc3d2e1f0;
65
66 ctx->total[0] = ctx->total[1] = 0;
67 ctx->buflen = 0;
68 }
69
70 /* Put result from CTX in first 20 bytes following RESBUF. The result
71 must be in little endian byte order.
72
73 IMPORTANT: On some systems it is required that RESBUF is correctly
74 aligned for a 32-bit value. */
75 void *
76 sha1_read_ctx (const struct sha1_ctx *ctx, void *resbuf)
77 {
78 ((sha1_uint32 *) resbuf)[0] = SWAP (ctx->A);
79 ((sha1_uint32 *) resbuf)[1] = SWAP (ctx->B);
80 ((sha1_uint32 *) resbuf)[2] = SWAP (ctx->C);
81 ((sha1_uint32 *) resbuf)[3] = SWAP (ctx->D);
82 ((sha1_uint32 *) resbuf)[4] = SWAP (ctx->E);
83
84 return resbuf;
85 }
86
87 /* Process the remaining bytes in the internal buffer and the usual
88 prolog according to the standard and write the result to RESBUF.
89
90 IMPORTANT: On some systems it is required that RESBUF is correctly
91 aligned for a 32-bit value. */
92 void *
93 sha1_finish_ctx (struct sha1_ctx *ctx, void *resbuf)
94 {
95 /* Take yet unprocessed bytes into account. */
96 sha1_uint32 bytes = ctx->buflen;
97 size_t size = (bytes < 56) ? 64 / 4 : 64 * 2 / 4;
98
99 /* Now count remaining bytes. */
100 ctx->total[0] += bytes;
101 if (ctx->total[0] < bytes)
102 ++ctx->total[1];
103
104 /* Put the 64-bit file length in *bits* at the end of the buffer. */
105 ctx->buffer[size - 2] = SWAP ((ctx->total[1] << 3) | (ctx->total[0] >> 29));
106 ctx->buffer[size - 1] = SWAP (ctx->total[0] << 3);
107
108 memcpy (&((char *) ctx->buffer)[bytes], fillbuf, (size - 2) * 4 - bytes);
109
110 /* Process last bytes. */
111 sha1_process_block (ctx->buffer, size * 4, ctx);
112
113 return sha1_read_ctx (ctx, resbuf);
114 }
115
116 /* Compute SHA1 message digest for bytes read from STREAM. The
117 resulting message digest number will be written into the 16 bytes
118 beginning at RESBLOCK. */
119 int
120 sha1_stream (FILE *stream, void *resblock)
121 {
122 struct sha1_ctx ctx;
123 char buffer[BLOCKSIZE + 72];
124 size_t sum;
125
126 /* Initialize the computation context. */
127 sha1_init_ctx (&ctx);
128
129 /* Iterate over full file contents. */
130 while (1)
131 {
132 /* We read the file in blocks of BLOCKSIZE bytes. One call of the
133 computation function processes the whole buffer so that with the
134 next round of the loop another block can be read. */
135 size_t n;
136 sum = 0;
137
138 /* Read block. Take care for partial reads. */
139 while (1)
140 {
141 n = fread (buffer + sum, 1, BLOCKSIZE - sum, stream);
142
143 sum += n;
144
145 if (sum == BLOCKSIZE)
146 break;
147
148 if (n == 0)
149 {
150 /* Check for the error flag IFF N == 0, so that we don't
151 exit the loop after a partial read due to e.g., EAGAIN
152 or EWOULDBLOCK. */
153 if (ferror (stream))
154 return 1;
155 goto process_partial_block;
156 }
157
158 /* We've read at least one byte, so ignore errors. But always
159 check for EOF, since feof may be true even though N > 0.
160 Otherwise, we could end up calling fread after EOF. */
161 if (feof (stream))
162 goto process_partial_block;
163 }
164
165 /* Process buffer with BLOCKSIZE bytes. Note that
166 BLOCKSIZE % 64 == 0
167 */
168 sha1_process_block (buffer, BLOCKSIZE, &ctx);
169 }
170
171 process_partial_block:;
172
173 /* Process any remaining bytes. */
174 if (sum > 0)
175 sha1_process_bytes (buffer, sum, &ctx);
176
177 /* Construct result in desired memory. */
178 sha1_finish_ctx (&ctx, resblock);
179 return 0;
180 }
181
182 /* Compute SHA1 message digest for LEN bytes beginning at BUFFER. The
183 result is always in little endian byte order, so that a byte-wise
184 output yields to the wanted ASCII representation of the message
185 digest. */
186 void *
187 sha1_buffer (const char *buffer, size_t len, void *resblock)
188 {
189 struct sha1_ctx ctx;
190
191 /* Initialize the computation context. */
192 sha1_init_ctx (&ctx);
193
194 /* Process whole buffer but last len % 64 bytes. */
195 sha1_process_bytes (buffer, len, &ctx);
196
197 /* Put result in desired memory area. */
198 return sha1_finish_ctx (&ctx, resblock);
199 }
200
201 void
202 sha1_process_bytes (const void *buffer, size_t len, struct sha1_ctx *ctx)
203 {
204 /* When we already have some bits in our internal buffer concatenate
205 both inputs first. */
206 if (ctx->buflen != 0)
207 {
208 size_t left_over = ctx->buflen;
209 size_t add = 128 - left_over > len ? len : 128 - left_over;
210
211 memcpy (&((char *) ctx->buffer)[left_over], buffer, add);
212 ctx->buflen += add;
213
214 if (ctx->buflen > 64)
215 {
216 sha1_process_block (ctx->buffer, ctx->buflen & ~63, ctx);
217
218 ctx->buflen &= 63;
219 /* The regions in the following copy operation cannot overlap. */
220 memcpy (ctx->buffer,
221 &((char *) ctx->buffer)[(left_over + add) & ~63],
222 ctx->buflen);
223 }
224
225 buffer = (const char *) buffer + add;
226 len -= add;
227 }
228
229 /* Process available complete blocks. */
230 if (len >= 64)
231 {
232 #if !_STRING_ARCH_unaligned
233 # define alignof(type) offsetof (struct { char c; type x; }, x)
234 # define UNALIGNED_P(p) (((size_t) p) % alignof (sha1_uint32) != 0)
235 if (UNALIGNED_P (buffer))
236 while (len > 64)
237 {
238 sha1_process_block (memcpy (ctx->buffer, buffer, 64), 64, ctx);
239 buffer = (const char *) buffer + 64;
240 len -= 64;
241 }
242 else
243 #endif
244 {
245 sha1_process_block (buffer, len & ~63, ctx);
246 buffer = (const char *) buffer + (len & ~63);
247 len &= 63;
248 }
249 }
250
251 /* Move remaining bytes in internal buffer. */
252 if (len > 0)
253 {
254 size_t left_over = ctx->buflen;
255
256 memcpy (&((char *) ctx->buffer)[left_over], buffer, len);
257 left_over += len;
258 if (left_over >= 64)
259 {
260 sha1_process_block (ctx->buffer, 64, ctx);
261 left_over -= 64;
262 memcpy (ctx->buffer, &ctx->buffer[16], left_over);
263 }
264 ctx->buflen = left_over;
265 }
266 }
267
268 /* --- Code below is the primary difference between md5.c and sha1.c --- */
269
270 /* SHA1 round constants */
271 #define K1 0x5a827999
272 #define K2 0x6ed9eba1
273 #define K3 0x8f1bbcdc
274 #define K4 0xca62c1d6
275
276 /* Round functions. Note that F2 is the same as F4. */
277 #define F1(B,C,D) ( D ^ ( B & ( C ^ D ) ) )
278 #define F2(B,C,D) (B ^ C ^ D)
279 #define F3(B,C,D) ( ( B & C ) | ( D & ( B | C ) ) )
280 #define F4(B,C,D) (B ^ C ^ D)
281
282 /* Process LEN bytes of BUFFER, accumulating context into CTX.
283 It is assumed that LEN % 64 == 0.
284 Most of this code comes from GnuPG's cipher/sha1.c. */
285
286 void
287 sha1_process_block (const void *buffer, size_t len, struct sha1_ctx *ctx)
288 {
289 const sha1_uint32 *words = (const sha1_uint32*) buffer;
290 size_t nwords = len / sizeof (sha1_uint32);
291 const sha1_uint32 *endp = words + nwords;
292 sha1_uint32 x[16];
293 sha1_uint32 a = ctx->A;
294 sha1_uint32 b = ctx->B;
295 sha1_uint32 c = ctx->C;
296 sha1_uint32 d = ctx->D;
297 sha1_uint32 e = ctx->E;
298
299 /* First increment the byte count. RFC 1321 specifies the possible
300 length of the file up to 2^64 bits. Here we only compute the
301 number of bytes. Do a double word increment. */
302 ctx->total[0] += len;
303 if (ctx->total[0] < len)
304 ++ctx->total[1];
305
306 #define rol(x, n) (((x) << (n)) | ((sha1_uint32) (x) >> (32 - (n))))
307
308 #define M(I) ( tm = x[I&0x0f] ^ x[(I-14)&0x0f] \
309 ^ x[(I-8)&0x0f] ^ x[(I-3)&0x0f] \
310 , (x[I&0x0f] = rol(tm, 1)) )
311
312 #define R(A,B,C,D,E,F,K,M) do { E += rol( A, 5 ) \
313 + F( B, C, D ) \
314 + K \
315 + M; \
316 B = rol( B, 30 ); \
317 } while(0)
318
319 while (words < endp)
320 {
321 sha1_uint32 tm;
322 int t;
323 for (t = 0; t < 16; t++)
324 {
325 x[t] = SWAP (*words);
326 words++;
327 }
328
329 R( a, b, c, d, e, F1, K1, x[ 0] );
330 R( e, a, b, c, d, F1, K1, x[ 1] );
331 R( d, e, a, b, c, F1, K1, x[ 2] );
332 R( c, d, e, a, b, F1, K1, x[ 3] );
333 R( b, c, d, e, a, F1, K1, x[ 4] );
334 R( a, b, c, d, e, F1, K1, x[ 5] );
335 R( e, a, b, c, d, F1, K1, x[ 6] );
336 R( d, e, a, b, c, F1, K1, x[ 7] );
337 R( c, d, e, a, b, F1, K1, x[ 8] );
338 R( b, c, d, e, a, F1, K1, x[ 9] );
339 R( a, b, c, d, e, F1, K1, x[10] );
340 R( e, a, b, c, d, F1, K1, x[11] );
341 R( d, e, a, b, c, F1, K1, x[12] );
342 R( c, d, e, a, b, F1, K1, x[13] );
343 R( b, c, d, e, a, F1, K1, x[14] );
344 R( a, b, c, d, e, F1, K1, x[15] );
345 R( e, a, b, c, d, F1, K1, M(16) );
346 R( d, e, a, b, c, F1, K1, M(17) );
347 R( c, d, e, a, b, F1, K1, M(18) );
348 R( b, c, d, e, a, F1, K1, M(19) );
349 R( a, b, c, d, e, F2, K2, M(20) );
350 R( e, a, b, c, d, F2, K2, M(21) );
351 R( d, e, a, b, c, F2, K2, M(22) );
352 R( c, d, e, a, b, F2, K2, M(23) );
353 R( b, c, d, e, a, F2, K2, M(24) );
354 R( a, b, c, d, e, F2, K2, M(25) );
355 R( e, a, b, c, d, F2, K2, M(26) );
356 R( d, e, a, b, c, F2, K2, M(27) );
357 R( c, d, e, a, b, F2, K2, M(28) );
358 R( b, c, d, e, a, F2, K2, M(29) );
359 R( a, b, c, d, e, F2, K2, M(30) );
360 R( e, a, b, c, d, F2, K2, M(31) );
361 R( d, e, a, b, c, F2, K2, M(32) );
362 R( c, d, e, a, b, F2, K2, M(33) );
363 R( b, c, d, e, a, F2, K2, M(34) );
364 R( a, b, c, d, e, F2, K2, M(35) );
365 R( e, a, b, c, d, F2, K2, M(36) );
366 R( d, e, a, b, c, F2, K2, M(37) );
367 R( c, d, e, a, b, F2, K2, M(38) );
368 R( b, c, d, e, a, F2, K2, M(39) );
369 R( a, b, c, d, e, F3, K3, M(40) );
370 R( e, a, b, c, d, F3, K3, M(41) );
371 R( d, e, a, b, c, F3, K3, M(42) );
372 R( c, d, e, a, b, F3, K3, M(43) );
373 R( b, c, d, e, a, F3, K3, M(44) );
374 R( a, b, c, d, e, F3, K3, M(45) );
375 R( e, a, b, c, d, F3, K3, M(46) );
376 R( d, e, a, b, c, F3, K3, M(47) );
377 R( c, d, e, a, b, F3, K3, M(48) );
378 R( b, c, d, e, a, F3, K3, M(49) );
379 R( a, b, c, d, e, F3, K3, M(50) );
380 R( e, a, b, c, d, F3, K3, M(51) );
381 R( d, e, a, b, c, F3, K3, M(52) );
382 R( c, d, e, a, b, F3, K3, M(53) );
383 R( b, c, d, e, a, F3, K3, M(54) );
384 R( a, b, c, d, e, F3, K3, M(55) );
385 R( e, a, b, c, d, F3, K3, M(56) );
386 R( d, e, a, b, c, F3, K3, M(57) );
387 R( c, d, e, a, b, F3, K3, M(58) );
388 R( b, c, d, e, a, F3, K3, M(59) );
389 R( a, b, c, d, e, F4, K4, M(60) );
390 R( e, a, b, c, d, F4, K4, M(61) );
391 R( d, e, a, b, c, F4, K4, M(62) );
392 R( c, d, e, a, b, F4, K4, M(63) );
393 R( b, c, d, e, a, F4, K4, M(64) );
394 R( a, b, c, d, e, F4, K4, M(65) );
395 R( e, a, b, c, d, F4, K4, M(66) );
396 R( d, e, a, b, c, F4, K4, M(67) );
397 R( c, d, e, a, b, F4, K4, M(68) );
398 R( b, c, d, e, a, F4, K4, M(69) );
399 R( a, b, c, d, e, F4, K4, M(70) );
400 R( e, a, b, c, d, F4, K4, M(71) );
401 R( d, e, a, b, c, F4, K4, M(72) );
402 R( c, d, e, a, b, F4, K4, M(73) );
403 R( b, c, d, e, a, F4, K4, M(74) );
404 R( a, b, c, d, e, F4, K4, M(75) );
405 R( e, a, b, c, d, F4, K4, M(76) );
406 R( d, e, a, b, c, F4, K4, M(77) );
407 R( c, d, e, a, b, F4, K4, M(78) );
408 R( b, c, d, e, a, F4, K4, M(79) );
409
410 a = ctx->A += a;
411 b = ctx->B += b;
412 c = ctx->C += c;
413 d = ctx->D += d;
414 e = ctx->E += e;
415 }
416 }