]>
git.ipfire.org Git - thirdparty/mdadm.git/blob - sha1.c
1 /* sha1.c - Functions to compute SHA1 message digest of files or
2 memory blocks according to the NIST specification FIPS-180-1.
4 Copyright (C) 2000, 2001, 2003, 2004, 2005 Free Software Foundation, Inc.
6 This program is free software; you can redistribute it and/or modify it
7 under the terms of the GNU General Public License as published by the
8 Free Software Foundation; either version 2, or (at your option) any
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software Foundation,
18 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
20 /* Written by Scott G. Miller
22 Robert Klep <robert@ilse.nl> -- Expansion function fix
35 # include "unlocked-io.h"
38 /* SWAP does an endian swap on architectures that are little-endian,
39 as SHA1 needs some data in a big-endian form. */
41 #ifdef WORDS_BIGENDIAN
45 (((n) << 24) | (((n) & 0xff00) << 8) | (((n) >> 8) & 0xff00) | ((n) >> 24))
48 #define BLOCKSIZE 4096
49 #if BLOCKSIZE % 64 != 0
50 # error "invalid BLOCKSIZE"
53 /* This array contains the bytes used to pad the buffer to the next
54 64-byte boundary. (RFC 1321, 3.1: Step 1) */
55 static const unsigned char fillbuf
[64] = { 0x80, 0 /* , 0, 0, ... */ };
59 Takes a pointer to a 160 bit block of data (five 32 bit ints) and
60 intializes it to the start constants of the SHA1 algorithm. This
61 must be called before using hash in the call to sha1_hash.
64 sha1_init_ctx (struct sha1_ctx
*ctx
)
72 ctx
->total
[0] = ctx
->total
[1] = 0;
76 /* Put result from CTX in first 20 bytes following RESBUF. The result
77 must be in little endian byte order.
79 IMPORTANT: On some systems it is required that RESBUF is correctly
80 aligned for a 32 bits value. */
82 sha1_read_ctx (const struct sha1_ctx
*ctx
, void *resbuf
)
84 ((md5_uint32
*) resbuf
)[0] = SWAP (ctx
->A
);
85 ((md5_uint32
*) resbuf
)[1] = SWAP (ctx
->B
);
86 ((md5_uint32
*) resbuf
)[2] = SWAP (ctx
->C
);
87 ((md5_uint32
*) resbuf
)[3] = SWAP (ctx
->D
);
88 ((md5_uint32
*) resbuf
)[4] = SWAP (ctx
->E
);
93 /* Process the remaining bytes in the internal buffer and the usual
94 prolog according to the standard and write the result to RESBUF.
96 IMPORTANT: On some systems it is required that RESBUF is correctly
97 aligned for a 32 bits value. */
99 sha1_finish_ctx (struct sha1_ctx
*ctx
, void *resbuf
)
101 /* Take yet unprocessed bytes into account. */
102 md5_uint32 bytes
= ctx
->buflen
;
105 /* Now count remaining bytes. */
106 ctx
->total
[0] += bytes
;
107 if (ctx
->total
[0] < bytes
)
110 pad
= bytes
>= 56 ? 64 + 56 - bytes
: 56 - bytes
;
111 memcpy (&ctx
->buffer
[bytes
], fillbuf
, pad
);
113 /* Put the 64-bit file length in *bits* at the end of the buffer. */
114 *(md5_uint32
*) &ctx
->buffer
[bytes
+ pad
+ 4] = SWAP (ctx
->total
[0] << 3);
115 *(md5_uint32
*) &ctx
->buffer
[bytes
+ pad
] = SWAP ((ctx
->total
[1] << 3) |
116 (ctx
->total
[0] >> 29));
118 /* Process last bytes. */
119 sha1_process_block (ctx
->buffer
, bytes
+ pad
+ 8, ctx
);
121 return sha1_read_ctx (ctx
, resbuf
);
124 /* Compute SHA1 message digest for bytes read from STREAM. The
125 resulting message digest number will be written into the 16 bytes
126 beginning at RESBLOCK. */
128 sha1_stream (FILE *stream
, void *resblock
)
131 char buffer
[BLOCKSIZE
+ 72];
134 /* Initialize the computation context. */
135 sha1_init_ctx (&ctx
);
137 /* Iterate over full file contents. */
140 /* We read the file in blocks of BLOCKSIZE bytes. One call of the
141 computation function processes the whole buffer so that with the
142 next round of the loop another block can be read. */
146 /* Read block. Take care for partial reads. */
149 n
= fread (buffer
+ sum
, 1, BLOCKSIZE
- sum
, stream
);
153 if (sum
== BLOCKSIZE
)
158 /* Check for the error flag IFF N == 0, so that we don't
159 exit the loop after a partial read due to e.g., EAGAIN
163 goto process_partial_block
;
166 /* We've read at least one byte, so ignore errors. But always
167 check for EOF, since feof may be true even though N > 0.
168 Otherwise, we could end up calling fread after EOF. */
170 goto process_partial_block
;
173 /* Process buffer with BLOCKSIZE bytes. Note that
176 sha1_process_block (buffer
, BLOCKSIZE
, &ctx
);
179 process_partial_block
:;
181 /* Process any remaining bytes. */
183 sha1_process_bytes (buffer
, sum
, &ctx
);
185 /* Construct result in desired memory. */
186 sha1_finish_ctx (&ctx
, resblock
);
190 /* Compute MD5 message digest for LEN bytes beginning at BUFFER. The
191 result is always in little endian byte order, so that a byte-wise
192 output yields to the wanted ASCII representation of the message
195 sha1_buffer (const char *buffer
, size_t len
, void *resblock
)
199 /* Initialize the computation context. */
200 sha1_init_ctx (&ctx
);
202 /* Process whole buffer but last len % 64 bytes. */
203 sha1_process_bytes (buffer
, len
, &ctx
);
205 /* Put result in desired memory area. */
206 return sha1_finish_ctx (&ctx
, resblock
);
210 sha1_process_bytes (const void *buffer
, size_t len
, struct sha1_ctx
*ctx
)
212 /* When we already have some bits in our internal buffer concatenate
213 both inputs first. */
214 if (ctx
->buflen
!= 0)
216 size_t left_over
= ctx
->buflen
;
217 size_t add
= 128 - left_over
> len
? len
: 128 - left_over
;
219 memcpy (&ctx
->buffer
[left_over
], buffer
, add
);
222 if (ctx
->buflen
> 64)
224 sha1_process_block (ctx
->buffer
, ctx
->buflen
& ~63, ctx
);
227 /* The regions in the following copy operation cannot overlap. */
228 memcpy (ctx
->buffer
, &ctx
->buffer
[(left_over
+ add
) & ~63],
232 buffer
= (const char *) buffer
+ add
;
236 /* Process available complete blocks. */
239 #if !_STRING_ARCH_unaligned
240 # define alignof(type) offsetof (struct { char c; type x; }, x)
241 # define UNALIGNED_P(p) (((size_t) p) % alignof (md5_uint32) != 0)
242 if (UNALIGNED_P (buffer
))
245 sha1_process_block (memcpy (ctx
->buffer
, buffer
, 64), 64, ctx
);
246 buffer
= (const char *) buffer
+ 64;
252 sha1_process_block (buffer
, len
& ~63, ctx
);
253 buffer
= (const char *) buffer
+ (len
& ~63);
258 /* Move remaining bytes in internal buffer. */
261 size_t left_over
= ctx
->buflen
;
263 memcpy (&ctx
->buffer
[left_over
], buffer
, len
);
267 sha1_process_block (ctx
->buffer
, 64, ctx
);
269 memcpy (ctx
->buffer
, &ctx
->buffer
[64], left_over
);
271 ctx
->buflen
= left_over
;
275 /* --- Code below is the primary difference between md5.c and sha1.c --- */
277 /* SHA1 round constants */
278 #define K1 0x5a827999L
279 #define K2 0x6ed9eba1L
280 #define K3 0x8f1bbcdcL
281 #define K4 0xca62c1d6L
283 /* Round functions. Note that F2 is the same as F4. */
284 #define F1(B,C,D) ( D ^ ( B & ( C ^ D ) ) )
285 #define F2(B,C,D) (B ^ C ^ D)
286 #define F3(B,C,D) ( ( B & C ) | ( D & ( B | C ) ) )
287 #define F4(B,C,D) (B ^ C ^ D)
289 /* Process LEN bytes of BUFFER, accumulating context into CTX.
290 It is assumed that LEN % 64 == 0.
291 Most of this code comes from GnuPG's cipher/sha1.c. */
294 sha1_process_block (const void *buffer
, size_t len
, struct sha1_ctx
*ctx
)
296 const md5_uint32
*words
= buffer
;
297 size_t nwords
= len
/ sizeof (md5_uint32
);
298 const md5_uint32
*endp
= words
+ nwords
;
300 md5_uint32 a
= ctx
->A
;
301 md5_uint32 b
= ctx
->B
;
302 md5_uint32 c
= ctx
->C
;
303 md5_uint32 d
= ctx
->D
;
304 md5_uint32 e
= ctx
->E
;
306 /* First increment the byte count. RFC 1321 specifies the possible
307 length of the file up to 2^64 bits. Here we only compute the
308 number of bytes. Do a double word increment. */
309 ctx
->total
[0] += len
;
310 if (ctx
->total
[0] < len
)
313 #define rol(x, n) (((x) << (n)) | ((x) >> (32 - (n))))
315 #define M(I) ( tm = x[I&0x0f] ^ x[(I-14)&0x0f] \
316 ^ x[(I-8)&0x0f] ^ x[(I-3)&0x0f] \
317 , (x[I&0x0f] = rol(tm, 1)) )
319 #define R(A,B,C,D,E,F,K,M) do { E += rol( A, 5 ) \
330 for (t
= 0; t
< 16; t
++)
332 x
[t
] = SWAP (*words
);
336 R( a
, b
, c
, d
, e
, F1
, K1
, x
[ 0] );
337 R( e
, a
, b
, c
, d
, F1
, K1
, x
[ 1] );
338 R( d
, e
, a
, b
, c
, F1
, K1
, x
[ 2] );
339 R( c
, d
, e
, a
, b
, F1
, K1
, x
[ 3] );
340 R( b
, c
, d
, e
, a
, F1
, K1
, x
[ 4] );
341 R( a
, b
, c
, d
, e
, F1
, K1
, x
[ 5] );
342 R( e
, a
, b
, c
, d
, F1
, K1
, x
[ 6] );
343 R( d
, e
, a
, b
, c
, F1
, K1
, x
[ 7] );
344 R( c
, d
, e
, a
, b
, F1
, K1
, x
[ 8] );
345 R( b
, c
, d
, e
, a
, F1
, K1
, x
[ 9] );
346 R( a
, b
, c
, d
, e
, F1
, K1
, x
[10] );
347 R( e
, a
, b
, c
, d
, F1
, K1
, x
[11] );
348 R( d
, e
, a
, b
, c
, F1
, K1
, x
[12] );
349 R( c
, d
, e
, a
, b
, F1
, K1
, x
[13] );
350 R( b
, c
, d
, e
, a
, F1
, K1
, x
[14] );
351 R( a
, b
, c
, d
, e
, F1
, K1
, x
[15] );
352 R( e
, a
, b
, c
, d
, F1
, K1
, M(16) );
353 R( d
, e
, a
, b
, c
, F1
, K1
, M(17) );
354 R( c
, d
, e
, a
, b
, F1
, K1
, M(18) );
355 R( b
, c
, d
, e
, a
, F1
, K1
, M(19) );
356 R( a
, b
, c
, d
, e
, F2
, K2
, M(20) );
357 R( e
, a
, b
, c
, d
, F2
, K2
, M(21) );
358 R( d
, e
, a
, b
, c
, F2
, K2
, M(22) );
359 R( c
, d
, e
, a
, b
, F2
, K2
, M(23) );
360 R( b
, c
, d
, e
, a
, F2
, K2
, M(24) );
361 R( a
, b
, c
, d
, e
, F2
, K2
, M(25) );
362 R( e
, a
, b
, c
, d
, F2
, K2
, M(26) );
363 R( d
, e
, a
, b
, c
, F2
, K2
, M(27) );
364 R( c
, d
, e
, a
, b
, F2
, K2
, M(28) );
365 R( b
, c
, d
, e
, a
, F2
, K2
, M(29) );
366 R( a
, b
, c
, d
, e
, F2
, K2
, M(30) );
367 R( e
, a
, b
, c
, d
, F2
, K2
, M(31) );
368 R( d
, e
, a
, b
, c
, F2
, K2
, M(32) );
369 R( c
, d
, e
, a
, b
, F2
, K2
, M(33) );
370 R( b
, c
, d
, e
, a
, F2
, K2
, M(34) );
371 R( a
, b
, c
, d
, e
, F2
, K2
, M(35) );
372 R( e
, a
, b
, c
, d
, F2
, K2
, M(36) );
373 R( d
, e
, a
, b
, c
, F2
, K2
, M(37) );
374 R( c
, d
, e
, a
, b
, F2
, K2
, M(38) );
375 R( b
, c
, d
, e
, a
, F2
, K2
, M(39) );
376 R( a
, b
, c
, d
, e
, F3
, K3
, M(40) );
377 R( e
, a
, b
, c
, d
, F3
, K3
, M(41) );
378 R( d
, e
, a
, b
, c
, F3
, K3
, M(42) );
379 R( c
, d
, e
, a
, b
, F3
, K3
, M(43) );
380 R( b
, c
, d
, e
, a
, F3
, K3
, M(44) );
381 R( a
, b
, c
, d
, e
, F3
, K3
, M(45) );
382 R( e
, a
, b
, c
, d
, F3
, K3
, M(46) );
383 R( d
, e
, a
, b
, c
, F3
, K3
, M(47) );
384 R( c
, d
, e
, a
, b
, F3
, K3
, M(48) );
385 R( b
, c
, d
, e
, a
, F3
, K3
, M(49) );
386 R( a
, b
, c
, d
, e
, F3
, K3
, M(50) );
387 R( e
, a
, b
, c
, d
, F3
, K3
, M(51) );
388 R( d
, e
, a
, b
, c
, F3
, K3
, M(52) );
389 R( c
, d
, e
, a
, b
, F3
, K3
, M(53) );
390 R( b
, c
, d
, e
, a
, F3
, K3
, M(54) );
391 R( a
, b
, c
, d
, e
, F3
, K3
, M(55) );
392 R( e
, a
, b
, c
, d
, F3
, K3
, M(56) );
393 R( d
, e
, a
, b
, c
, F3
, K3
, M(57) );
394 R( c
, d
, e
, a
, b
, F3
, K3
, M(58) );
395 R( b
, c
, d
, e
, a
, F3
, K3
, M(59) );
396 R( a
, b
, c
, d
, e
, F4
, K4
, M(60) );
397 R( e
, a
, b
, c
, d
, F4
, K4
, M(61) );
398 R( d
, e
, a
, b
, c
, F4
, K4
, M(62) );
399 R( c
, d
, e
, a
, b
, F4
, K4
, M(63) );
400 R( b
, c
, d
, e
, a
, F4
, K4
, M(64) );
401 R( a
, b
, c
, d
, e
, F4
, K4
, M(65) );
402 R( e
, a
, b
, c
, d
, F4
, K4
, M(66) );
403 R( d
, e
, a
, b
, c
, F4
, K4
, M(67) );
404 R( c
, d
, e
, a
, b
, F4
, K4
, M(68) );
405 R( b
, c
, d
, e
, a
, F4
, K4
, M(69) );
406 R( a
, b
, c
, d
, e
, F4
, K4
, M(70) );
407 R( e
, a
, b
, c
, d
, F4
, K4
, M(71) );
408 R( d
, e
, a
, b
, c
, F4
, K4
, M(72) );
409 R( c
, d
, e
, a
, b
, F4
, K4
, M(73) );
410 R( b
, c
, d
, e
, a
, F4
, K4
, M(74) );
411 R( a
, b
, c
, d
, e
, F4
, K4
, M(75) );
412 R( e
, a
, b
, c
, d
, F4
, K4
, M(76) );
413 R( d
, e
, a
, b
, c
, F4
, K4
, M(77) );
414 R( c
, d
, e
, a
, b
, F4
, K4
, M(78) );
415 R( b
, c
, d
, e
, a
, F4
, K4
, M(79) );