]>
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
;
106 /* Now count remaining bytes. */
107 ctx
->total
[0] += bytes
;
108 if (ctx
->total
[0] < bytes
)
111 pad
= bytes
>= 56 ? 64 + 56 - bytes
: 56 - bytes
;
112 memcpy (&ctx
->buffer
[bytes
], fillbuf
, pad
);
114 /* Put the 64-bit file length in *bits* at the end of the buffer. */
115 ptr
= (md5_uint32
*) &ctx
->buffer
[bytes
+ pad
+ 4];
116 *ptr
= SWAP (ctx
->total
[0] << 3);
117 ptr
= (md5_uint32
*) &ctx
->buffer
[bytes
+ pad
];
118 *ptr
= SWAP ((ctx
->total
[1] << 3) | (ctx
->total
[0] >> 29));
120 /* Process last bytes. */
121 sha1_process_block (ctx
->buffer
, bytes
+ pad
+ 8, ctx
);
123 return sha1_read_ctx (ctx
, resbuf
);
126 /* Compute SHA1 message digest for bytes read from STREAM. The
127 resulting message digest number will be written into the 16 bytes
128 beginning at RESBLOCK. */
130 sha1_stream (FILE *stream
, void *resblock
)
133 char buffer
[BLOCKSIZE
+ 72];
136 /* Initialize the computation context. */
137 sha1_init_ctx (&ctx
);
139 /* Iterate over full file contents. */
142 /* We read the file in blocks of BLOCKSIZE bytes. One call of the
143 computation function processes the whole buffer so that with the
144 next round of the loop another block can be read. */
148 /* Read block. Take care for partial reads. */
151 n
= fread (buffer
+ sum
, 1, BLOCKSIZE
- sum
, stream
);
155 if (sum
== BLOCKSIZE
)
160 /* Check for the error flag IFF N == 0, so that we don't
161 exit the loop after a partial read due to e.g., EAGAIN
165 goto process_partial_block
;
168 /* We've read at least one byte, so ignore errors. But always
169 check for EOF, since feof may be true even though N > 0.
170 Otherwise, we could end up calling fread after EOF. */
172 goto process_partial_block
;
175 /* Process buffer with BLOCKSIZE bytes. Note that
178 sha1_process_block (buffer
, BLOCKSIZE
, &ctx
);
181 process_partial_block
:;
183 /* Process any remaining bytes. */
185 sha1_process_bytes (buffer
, sum
, &ctx
);
187 /* Construct result in desired memory. */
188 sha1_finish_ctx (&ctx
, resblock
);
192 /* Compute MD5 message digest for LEN bytes beginning at BUFFER. The
193 result is always in little endian byte order, so that a byte-wise
194 output yields to the wanted ASCII representation of the message
197 sha1_buffer (const char *buffer
, size_t len
, void *resblock
)
201 /* Initialize the computation context. */
202 sha1_init_ctx (&ctx
);
204 /* Process whole buffer but last len % 64 bytes. */
205 sha1_process_bytes (buffer
, len
, &ctx
);
207 /* Put result in desired memory area. */
208 return sha1_finish_ctx (&ctx
, resblock
);
212 sha1_process_bytes (const void *buffer
, size_t len
, struct sha1_ctx
*ctx
)
214 /* When we already have some bits in our internal buffer concatenate
215 both inputs first. */
216 if (ctx
->buflen
!= 0)
218 size_t left_over
= ctx
->buflen
;
219 size_t add
= 128 - left_over
> len
? len
: 128 - left_over
;
221 memcpy (&ctx
->buffer
[left_over
], buffer
, add
);
224 if (ctx
->buflen
> 64)
226 sha1_process_block (ctx
->buffer
, ctx
->buflen
& ~63, ctx
);
229 /* The regions in the following copy operation cannot overlap. */
230 memcpy (ctx
->buffer
, &ctx
->buffer
[(left_over
+ add
) & ~63],
234 buffer
= (const char *) buffer
+ add
;
238 /* Process available complete blocks. */
241 #if !_STRING_ARCH_unaligned
242 # define alignof(type) offsetof (struct { char c; type x; }, x)
243 # define UNALIGNED_P(p) (((size_t) p) % alignof (md5_uint32) != 0)
244 if (UNALIGNED_P (buffer
))
247 sha1_process_block (memcpy (ctx
->buffer
, buffer
, 64), 64, ctx
);
248 buffer
= (const char *) buffer
+ 64;
254 sha1_process_block (buffer
, len
& ~63, ctx
);
255 buffer
= (const char *) buffer
+ (len
& ~63);
260 /* Move remaining bytes in internal buffer. */
263 size_t left_over
= ctx
->buflen
;
265 memcpy (&ctx
->buffer
[left_over
], buffer
, len
);
269 sha1_process_block (ctx
->buffer
, 64, ctx
);
271 memcpy (ctx
->buffer
, &ctx
->buffer
[64], left_over
);
273 ctx
->buflen
= left_over
;
277 /* --- Code below is the primary difference between md5.c and sha1.c --- */
279 /* SHA1 round constants */
280 #define K1 0x5a827999L
281 #define K2 0x6ed9eba1L
282 #define K3 0x8f1bbcdcL
283 #define K4 0xca62c1d6L
285 /* Round functions. Note that F2 is the same as F4. */
286 #define F1(B,C,D) ( D ^ ( B & ( C ^ D ) ) )
287 #define F2(B,C,D) (B ^ C ^ D)
288 #define F3(B,C,D) ( ( B & C ) | ( D & ( B | C ) ) )
289 #define F4(B,C,D) (B ^ C ^ D)
291 /* Process LEN bytes of BUFFER, accumulating context into CTX.
292 It is assumed that LEN % 64 == 0.
293 Most of this code comes from GnuPG's cipher/sha1.c. */
296 sha1_process_block (const void *buffer
, size_t len
, struct sha1_ctx
*ctx
)
298 const md5_uint32
*words
= buffer
;
299 size_t nwords
= len
/ sizeof (md5_uint32
);
300 const md5_uint32
*endp
= words
+ nwords
;
302 md5_uint32 a
= ctx
->A
;
303 md5_uint32 b
= ctx
->B
;
304 md5_uint32 c
= ctx
->C
;
305 md5_uint32 d
= ctx
->D
;
306 md5_uint32 e
= ctx
->E
;
308 /* First increment the byte count. RFC 1321 specifies the possible
309 length of the file up to 2^64 bits. Here we only compute the
310 number of bytes. Do a double word increment. */
311 ctx
->total
[0] += len
;
312 if (ctx
->total
[0] < len
)
315 #define rol(x, n) (((x) << (n)) | ((x) >> (32 - (n))))
317 #define M(I) ( tm = x[I&0x0f] ^ x[(I-14)&0x0f] \
318 ^ x[(I-8)&0x0f] ^ x[(I-3)&0x0f] \
319 , (x[I&0x0f] = rol(tm, 1)) )
321 #define R(A,B,C,D,E,F,K,M) do { E += rol( A, 5 ) \
332 for (t
= 0; t
< 16; t
++)
334 x
[t
] = SWAP (*words
);
338 R( a
, b
, c
, d
, e
, F1
, K1
, x
[ 0] );
339 R( e
, a
, b
, c
, d
, F1
, K1
, x
[ 1] );
340 R( d
, e
, a
, b
, c
, F1
, K1
, x
[ 2] );
341 R( c
, d
, e
, a
, b
, F1
, K1
, x
[ 3] );
342 R( b
, c
, d
, e
, a
, F1
, K1
, x
[ 4] );
343 R( a
, b
, c
, d
, e
, F1
, K1
, x
[ 5] );
344 R( e
, a
, b
, c
, d
, F1
, K1
, x
[ 6] );
345 R( d
, e
, a
, b
, c
, F1
, K1
, x
[ 7] );
346 R( c
, d
, e
, a
, b
, F1
, K1
, x
[ 8] );
347 R( b
, c
, d
, e
, a
, F1
, K1
, x
[ 9] );
348 R( a
, b
, c
, d
, e
, F1
, K1
, x
[10] );
349 R( e
, a
, b
, c
, d
, F1
, K1
, x
[11] );
350 R( d
, e
, a
, b
, c
, F1
, K1
, x
[12] );
351 R( c
, d
, e
, a
, b
, F1
, K1
, x
[13] );
352 R( b
, c
, d
, e
, a
, F1
, K1
, x
[14] );
353 R( a
, b
, c
, d
, e
, F1
, K1
, x
[15] );
354 R( e
, a
, b
, c
, d
, F1
, K1
, M(16) );
355 R( d
, e
, a
, b
, c
, F1
, K1
, M(17) );
356 R( c
, d
, e
, a
, b
, F1
, K1
, M(18) );
357 R( b
, c
, d
, e
, a
, F1
, K1
, M(19) );
358 R( a
, b
, c
, d
, e
, F2
, K2
, M(20) );
359 R( e
, a
, b
, c
, d
, F2
, K2
, M(21) );
360 R( d
, e
, a
, b
, c
, F2
, K2
, M(22) );
361 R( c
, d
, e
, a
, b
, F2
, K2
, M(23) );
362 R( b
, c
, d
, e
, a
, F2
, K2
, M(24) );
363 R( a
, b
, c
, d
, e
, F2
, K2
, M(25) );
364 R( e
, a
, b
, c
, d
, F2
, K2
, M(26) );
365 R( d
, e
, a
, b
, c
, F2
, K2
, M(27) );
366 R( c
, d
, e
, a
, b
, F2
, K2
, M(28) );
367 R( b
, c
, d
, e
, a
, F2
, K2
, M(29) );
368 R( a
, b
, c
, d
, e
, F2
, K2
, M(30) );
369 R( e
, a
, b
, c
, d
, F2
, K2
, M(31) );
370 R( d
, e
, a
, b
, c
, F2
, K2
, M(32) );
371 R( c
, d
, e
, a
, b
, F2
, K2
, M(33) );
372 R( b
, c
, d
, e
, a
, F2
, K2
, M(34) );
373 R( a
, b
, c
, d
, e
, F2
, K2
, M(35) );
374 R( e
, a
, b
, c
, d
, F2
, K2
, M(36) );
375 R( d
, e
, a
, b
, c
, F2
, K2
, M(37) );
376 R( c
, d
, e
, a
, b
, F2
, K2
, M(38) );
377 R( b
, c
, d
, e
, a
, F2
, K2
, M(39) );
378 R( a
, b
, c
, d
, e
, F3
, K3
, M(40) );
379 R( e
, a
, b
, c
, d
, F3
, K3
, M(41) );
380 R( d
, e
, a
, b
, c
, F3
, K3
, M(42) );
381 R( c
, d
, e
, a
, b
, F3
, K3
, M(43) );
382 R( b
, c
, d
, e
, a
, F3
, K3
, M(44) );
383 R( a
, b
, c
, d
, e
, F3
, K3
, M(45) );
384 R( e
, a
, b
, c
, d
, F3
, K3
, M(46) );
385 R( d
, e
, a
, b
, c
, F3
, K3
, M(47) );
386 R( c
, d
, e
, a
, b
, F3
, K3
, M(48) );
387 R( b
, c
, d
, e
, a
, F3
, K3
, M(49) );
388 R( a
, b
, c
, d
, e
, F3
, K3
, M(50) );
389 R( e
, a
, b
, c
, d
, F3
, K3
, M(51) );
390 R( d
, e
, a
, b
, c
, F3
, K3
, M(52) );
391 R( c
, d
, e
, a
, b
, F3
, K3
, M(53) );
392 R( b
, c
, d
, e
, a
, F3
, K3
, M(54) );
393 R( a
, b
, c
, d
, e
, F3
, K3
, M(55) );
394 R( e
, a
, b
, c
, d
, F3
, K3
, M(56) );
395 R( d
, e
, a
, b
, c
, F3
, K3
, M(57) );
396 R( c
, d
, e
, a
, b
, F3
, K3
, M(58) );
397 R( b
, c
, d
, e
, a
, F3
, K3
, M(59) );
398 R( a
, b
, c
, d
, e
, F4
, K4
, M(60) );
399 R( e
, a
, b
, c
, d
, F4
, K4
, M(61) );
400 R( d
, e
, a
, b
, c
, F4
, K4
, M(62) );
401 R( c
, d
, e
, a
, b
, F4
, K4
, M(63) );
402 R( b
, c
, d
, e
, a
, F4
, K4
, M(64) );
403 R( a
, b
, c
, d
, e
, F4
, K4
, M(65) );
404 R( e
, a
, b
, c
, d
, F4
, K4
, M(66) );
405 R( d
, e
, a
, b
, c
, F4
, K4
, M(67) );
406 R( c
, d
, e
, a
, b
, F4
, K4
, M(68) );
407 R( b
, c
, d
, e
, a
, F4
, K4
, M(69) );
408 R( a
, b
, c
, d
, e
, F4
, K4
, M(70) );
409 R( e
, a
, b
, c
, d
, F4
, K4
, M(71) );
410 R( d
, e
, a
, b
, c
, F4
, K4
, M(72) );
411 R( c
, d
, e
, a
, b
, F4
, K4
, M(73) );
412 R( b
, c
, d
, e
, a
, F4
, K4
, M(74) );
413 R( a
, b
, c
, d
, e
, F4
, K4
, M(75) );
414 R( e
, a
, b
, c
, d
, F4
, K4
, M(76) );
415 R( d
, e
, a
, b
, c
, F4
, K4
, M(77) );
416 R( c
, d
, e
, a
, b
, F4
, K4
, M(78) );
417 R( b
, c
, d
, e
, a
, F4
, K4
, M(79) );