summaryrefslogtreecommitdiff
path: root/libbb/sha1.c
blob: 3e61aff6dad8bf2ccd6e9aa47f8b1cbb9a2b78b3 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
/* vi: set sw=4 ts=4: */
/*
 * Based on shasum from http://www.netsw.org/crypto/hash/
 * Majorly hacked up to use Dr Brian Gladman's sha1 code
 *
 * Copyright (C) 2002 Dr Brian Gladman <brg@gladman.me.uk>, Worcester, UK.
 * Copyright (C) 2003 Glenn L. McGrath
 * Copyright (C) 2003 Erik Andersen
 *
 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
 *
 * ---------------------------------------------------------------------------
 * Issue Date: 10/11/2002
 *
 * This is a byte oriented version of SHA1 that operates on arrays of bytes
 * stored in memory. It runs at 22 cycles per byte on a Pentium P4 processor
 *
 * ---------------------------------------------------------------------------
 *
 * SHA256 and SHA512 parts are:
 * Released into the Public Domain by Ulrich Drepper <drepper@redhat.com>.
 * Shrank by Denys Vlasenko.
 *
 * ---------------------------------------------------------------------------
 *
 * The best way to test random blocksizes is to go to coreutils/md5_sha1_sum.c
 * and replace "4096" with something like "2000 + time(NULL) % 2097",
 * then rebuild and compare "shaNNNsum bigfile" results.
 */

#include "libbb.h"

/* gcc 4.2.1 optimizes rotr64 better with inline than with macro
 * (for rotX32, there is no difference). Why? My guess is that
 * macro requires clever common subexpression elimination heuristics
 * in gcc, while inline basically forces it to happen.
 */
//#define rotl32(x,n) (((x) << (n)) | ((x) >> (32 - (n))))
static ALWAYS_INLINE uint32_t rotl32(uint32_t x, unsigned n)
{
	return (x << n) | (x >> (32 - n));
}
//#define rotr32(x,n) (((x) >> (n)) | ((x) << (32 - (n))))
static ALWAYS_INLINE uint32_t rotr32(uint32_t x, unsigned n)
{
	return (x >> n) | (x << (32 - n));
}
/* rotr64 in needed for sha512 only: */
//#define rotr64(x,n) (((x) >> (n)) | ((x) << (64 - (n))))
static ALWAYS_INLINE uint64_t rotr64(uint64_t x, unsigned n)
{
	return (x >> n) | (x << (64 - n));
}
#if BB_LITTLE_ENDIAN
/* ALWAYS_INLINE below would hurt code size, using plain inline: */
static inline uint64_t hton64(uint64_t v)
{
	return (((uint64_t)htonl(v)) << 32) | htonl(v >> 32);
}
#else
#define hton64(v) (v)
#endif
#define ntoh64(v) hton64(v)


/* Some arch headers have conflicting defines */
#undef ch
#undef parity
#undef maj
#undef rnd

static void FAST_FUNC sha1_process_block64(sha1_ctx_t *ctx)
{
	unsigned t;
	uint32_t W[80], a, b, c, d, e;
	const uint32_t *words = (uint32_t*) ctx->wbuffer;

	for (t = 0; t < 16; ++t)
		W[t] = ntohl(words[t]);
	for (/*t = 16*/; t < 80; ++t) {
		uint32_t T = W[t - 3] ^ W[t - 8] ^ W[t - 14] ^ W[t - 16];
		W[t] = rotl32(T, 1);
	}

	a = ctx->hash[0];
	b = ctx->hash[1];
	c = ctx->hash[2];
	d = ctx->hash[3];
	e = ctx->hash[4];

/* Reverse byte order in 32-bit words   */
#define ch(x,y,z)        ((z) ^ ((x) & ((y) ^ (z))))
#define parity(x,y,z)    ((x) ^ (y) ^ (z))
#define maj(x,y,z)       (((x) & (y)) | ((z) & ((x) | (y))))
/* A normal version as set out in the FIPS. This version uses   */
/* partial loop unrolling and is optimised for the Pentium 4    */
#define rnd(f,k) \
	do { \
		uint32_t T = a; \
		a = rotl32(a, 5) + f(b, c, d) + e + k + W[t]; \
		e = d; \
		d = c; \
		c = rotl32(b, 30); \
		b = T; \
	} while (0)

	for (t = 0; t < 20; ++t)
		rnd(ch, 0x5a827999);

	for (/*t = 20*/; t < 40; ++t)
		rnd(parity, 0x6ed9eba1);

	for (/*t = 40*/; t < 60; ++t)
		rnd(maj, 0x8f1bbcdc);

	for (/*t = 60*/; t < 80; ++t)
		rnd(parity, 0xca62c1d6);
#undef ch
#undef parity
#undef maj
#undef rnd

	ctx->hash[0] += a;
	ctx->hash[1] += b;
	ctx->hash[2] += c;
	ctx->hash[3] += d;
	ctx->hash[4] += e;
}

/* Constants for SHA512 from FIPS 180-2:4.2.3.
 * SHA256 constants from FIPS 180-2:4.2.2
 * are the most significant half of first 64 elements
 * of the same array.
 */
static const uint64_t sha_K[80] = {
	0x428a2f98d728ae22ULL, 0x7137449123ef65cdULL,
	0xb5c0fbcfec4d3b2fULL, 0xe9b5dba58189dbbcULL,
	0x3956c25bf348b538ULL, 0x59f111f1b605d019ULL,
	0x923f82a4af194f9bULL, 0xab1c5ed5da6d8118ULL,
	0xd807aa98a3030242ULL, 0x12835b0145706fbeULL,
	0x243185be4ee4b28cULL, 0x550c7dc3d5ffb4e2ULL,
	0x72be5d74f27b896fULL, 0x80deb1fe3b1696b1ULL,
	0x9bdc06a725c71235ULL, 0xc19bf174cf692694ULL,
	0xe49b69c19ef14ad2ULL, 0xefbe4786384f25e3ULL,
	0x0fc19dc68b8cd5b5ULL, 0x240ca1cc77ac9c65ULL,
	0x2de92c6f592b0275ULL, 0x4a7484aa6ea6e483ULL,
	0x5cb0a9dcbd41fbd4ULL, 0x76f988da831153b5ULL,
	0x983e5152ee66dfabULL, 0xa831c66d2db43210ULL,
	0xb00327c898fb213fULL, 0xbf597fc7beef0ee4ULL,
	0xc6e00bf33da88fc2ULL, 0xd5a79147930aa725ULL,
	0x06ca6351e003826fULL, 0x142929670a0e6e70ULL,
	0x27b70a8546d22ffcULL, 0x2e1b21385c26c926ULL,
	0x4d2c6dfc5ac42aedULL, 0x53380d139d95b3dfULL,
	0x650a73548baf63deULL, 0x766a0abb3c77b2a8ULL,
	0x81c2c92e47edaee6ULL, 0x92722c851482353bULL,
	0xa2bfe8a14cf10364ULL, 0xa81a664bbc423001ULL,
	0xc24b8b70d0f89791ULL, 0xc76c51a30654be30ULL,
	0xd192e819d6ef5218ULL, 0xd69906245565a910ULL,
	0xf40e35855771202aULL, 0x106aa07032bbd1b8ULL,
	0x19a4c116b8d2d0c8ULL, 0x1e376c085141ab53ULL,
	0x2748774cdf8eeb99ULL, 0x34b0bcb5e19b48a8ULL,
	0x391c0cb3c5c95a63ULL, 0x4ed8aa4ae3418acbULL,
	0x5b9cca4f7763e373ULL, 0x682e6ff3d6b2b8a3ULL,
	0x748f82ee5defb2fcULL, 0x78a5636f43172f60ULL,
	0x84c87814a1f0ab72ULL, 0x8cc702081a6439ecULL,
	0x90befffa23631e28ULL, 0xa4506cebde82bde9ULL,
	0xbef9a3f7b2c67915ULL, 0xc67178f2e372532bULL,
	0xca273eceea26619cULL, 0xd186b8c721c0c207ULL, /* [64]+ are used for sha512 only */
	0xeada7dd6cde0eb1eULL, 0xf57d4f7fee6ed178ULL,
	0x06f067aa72176fbaULL, 0x0a637dc5a2c898a6ULL,
	0x113f9804bef90daeULL, 0x1b710b35131c471bULL,
	0x28db77f523047d84ULL, 0x32caab7b40c72493ULL,
	0x3c9ebe0a15c9bebcULL, 0x431d67c49c100d4cULL,
	0x4cc5d4becb3e42b6ULL, 0x597f299cfc657e2aULL,
	0x5fcb6fab3ad6faecULL, 0x6c44198c4a475817ULL
};

#undef Ch
#undef Maj
#undef S0
#undef S1
#undef R0
#undef R1

static void FAST_FUNC sha256_process_block64(sha256_ctx_t *ctx)
{
	unsigned t;
	uint32_t W[64], a, b, c, d, e, f, g, h;
	const uint32_t *words = (uint32_t*) ctx->wbuffer;

	/* Operators defined in FIPS 180-2:4.1.2.  */
#define Ch(x, y, z) ((x & y) ^ (~x & z))
#define Maj(x, y, z) ((x & y) ^ (x & z) ^ (y & z))
#define S0(x) (rotr32(x, 2) ^ rotr32(x, 13) ^ rotr32(x, 22))
#define S1(x) (rotr32(x, 6) ^ rotr32(x, 11) ^ rotr32(x, 25))
#define R0(x) (rotr32(x, 7) ^ rotr32(x, 18) ^ (x >> 3))
#define R1(x) (rotr32(x, 17) ^ rotr32(x, 19) ^ (x >> 10))

	/* Compute the message schedule according to FIPS 180-2:6.2.2 step 2.  */
	for (t = 0; t < 16; ++t)
		W[t] = ntohl(words[t]);
	for (/*t = 16*/; t < 64; ++t)
		W[t] = R1(W[t - 2]) + W[t - 7] + R0(W[t - 15]) + W[t - 16];

	a = ctx->hash[0];
	b = ctx->hash[1];
	c = ctx->hash[2];
	d = ctx->hash[3];
	e = ctx->hash[4];
	f = ctx->hash[5];
	g = ctx->hash[6];
	h = ctx->hash[7];

	/* The actual computation according to FIPS 180-2:6.2.2 step 3.  */
	for (t = 0; t < 64; ++t) {
		/* Need to fetch upper half of sha_K[t]
		 * (I hope compiler is clever enough to just fetch
		 * upper half)
		 */
		uint32_t K_t = sha_K[t] >> 32;
		uint32_t T1 = h + S1(e) + Ch(e, f, g) + K_t + W[t];
		uint32_t T2 = S0(a) + Maj(a, b, c);
		h = g;
		g = f;
		f = e;
		e = d + T1;
		d = c;
		c = b;
		b = a;
		a = T1 + T2;
	}
#undef Ch
#undef Maj
#undef S0
#undef S1
#undef R0
#undef R1
	/* Add the starting values of the context according to FIPS 180-2:6.2.2
	   step 4.  */
	ctx->hash[0] += a;
	ctx->hash[1] += b;
	ctx->hash[2] += c;
	ctx->hash[3] += d;
	ctx->hash[4] += e;
	ctx->hash[5] += f;
	ctx->hash[6] += g;
	ctx->hash[7] += h;
}

static void FAST_FUNC sha512_process_block128(sha512_ctx_t *ctx)
{
	unsigned t;
	uint64_t W[80];
	/* On i386, having assignments here (not later as sha256 does)
	 * produces 99 bytes smaller code with gcc 4.3.1
	 */
	uint64_t a = ctx->hash[0];
	uint64_t b = ctx->hash[1];
	uint64_t c = ctx->hash[2];
	uint64_t d = ctx->hash[3];
	uint64_t e = ctx->hash[4];
	uint64_t f = ctx->hash[5];
	uint64_t g = ctx->hash[6];
	uint64_t h = ctx->hash[7];
	const uint64_t *words = (uint64_t*) ctx->wbuffer;

	/* Operators defined in FIPS 180-2:4.1.2.  */
#define Ch(x, y, z) ((x & y) ^ (~x & z))
#define Maj(x, y, z) ((x & y) ^ (x & z) ^ (y & z))
#define S0(x) (rotr64(x, 28) ^ rotr64(x, 34) ^ rotr64(x, 39))
#define S1(x) (rotr64(x, 14) ^ rotr64(x, 18) ^ rotr64(x, 41))
#define R0(x) (rotr64(x, 1) ^ rotr64(x, 8) ^ (x >> 7))
#define R1(x) (rotr64(x, 19) ^ rotr64(x, 61) ^ (x >> 6))

	/* Compute the message schedule according to FIPS 180-2:6.3.2 step 2.  */
	for (t = 0; t < 16; ++t)
		W[t] = ntoh64(words[t]);
	for (/*t = 16*/; t < 80; ++t)
		W[t] = R1(W[t - 2]) + W[t - 7] + R0(W[t - 15]) + W[t - 16];

	/* The actual computation according to FIPS 180-2:6.3.2 step 3.  */
	for (t = 0; t < 80; ++t) {
		uint64_t T1 = h + S1(e) + Ch(e, f, g) + sha_K[t] + W[t];
		uint64_t T2 = S0(a) + Maj(a, b, c);
		h = g;
		g = f;
		f = e;
		e = d + T1;
		d = c;
		c = b;
		b = a;
		a = T1 + T2;
	}
#undef Ch
#undef Maj
#undef S0
#undef S1
#undef R0
#undef R1
	/* Add the starting values of the context according to FIPS 180-2:6.3.2
	   step 4.  */
	ctx->hash[0] += a;
	ctx->hash[1] += b;
	ctx->hash[2] += c;
	ctx->hash[3] += d;
	ctx->hash[4] += e;
	ctx->hash[5] += f;
	ctx->hash[6] += g;
	ctx->hash[7] += h;
}


void FAST_FUNC sha1_begin(sha1_ctx_t *ctx)
{
	ctx->hash[0] = 0x67452301;
	ctx->hash[1] = 0xefcdab89;
	ctx->hash[2] = 0x98badcfe;
	ctx->hash[3] = 0x10325476;
	ctx->hash[4] = 0xc3d2e1f0;
	ctx->total64 = 0;
	ctx->process_block = sha1_process_block64;
}

static const uint32_t init256[] = {
	0x6a09e667,
	0xbb67ae85,
	0x3c6ef372,
	0xa54ff53a,
	0x510e527f,
	0x9b05688c,
	0x1f83d9ab,
	0x5be0cd19,
	0,
	0,
};
static const uint32_t init512_lo[] = {
	0xf3bcc908,
	0x84caa73b,
	0xfe94f82b,
	0x5f1d36f1,
	0xade682d1,
	0x2b3e6c1f,
	0xfb41bd6b,
	0x137e2179,
	0,
	0,
};

/* Initialize structure containing state of computation.
   (FIPS 180-2:5.3.2)  */
void FAST_FUNC sha256_begin(sha256_ctx_t *ctx)
{
	memcpy(ctx->hash, init256, sizeof(init256));
	/*ctx->total64 = 0; - done by extending init256 with two 32-bit zeros */
	ctx->process_block = sha256_process_block64;
}

/* Initialize structure containing state of computation.
   (FIPS 180-2:5.3.3)  */
void FAST_FUNC sha512_begin(sha512_ctx_t *ctx)
{
	int i;
	/* Two extra iterations zero out ctx->total64[] */
	for (i = 0; i < 8+2; i++)
		ctx->hash[i] = ((uint64_t)(init256[i]) << 32) + init512_lo[i];
	/*ctx->total64[0] = ctx->total64[1] = 0; - already done */
}


/* Used also for sha256 */
void FAST_FUNC sha1_hash(sha1_ctx_t *ctx, const void *buffer, size_t len)
{
	unsigned bufpos = ctx->total64 & 63;
	unsigned remaining;

	ctx->total64 += len;
#if 0
	remaining = 64 - bufpos;

	/* Hash whole blocks */
	while (len >= remaining) {
		memcpy(ctx->wbuffer + bufpos, buffer, remaining);
		buffer = (const char *)buffer + remaining;
		len -= remaining;
		remaining = 64;
		bufpos = 0;
		ctx->process_block(ctx);
	}

	/* Save last, partial blosk */
	memcpy(ctx->wbuffer + bufpos, buffer, len);
#else
	/* Tiny bit smaller code */
	while (1) {
		remaining = 64 - bufpos;
		if (remaining > len)
			remaining = len;
		/* Copy data into aligned buffer */
		memcpy(ctx->wbuffer + bufpos, buffer, remaining);
		len -= remaining;
		buffer = (const char *)buffer + remaining;
		bufpos += remaining;
		/* clever way to do "if (bufpos != 64) break; ... ; bufpos = 0;" */
		bufpos -= 64;
		if (bufpos != 0)
			break;
		/* Buffer is filled up, process it */
		ctx->process_block(ctx);
		/*bufpos = 0; - already is */
	}
#endif
}

void FAST_FUNC sha512_hash(sha512_ctx_t *ctx, const void *buffer, size_t len)
{
	unsigned bufpos = ctx->total64[0] & 127;
	unsigned remaining;

	/* First increment the byte count.  FIPS 180-2 specifies the possible
	   length of the file up to 2^128 _bits_.
	   We compute the number of _bytes_ and convert to bits later.  */
	ctx->total64[0] += len;
	if (ctx->total64[0] < len)
		ctx->total64[1]++;
#if 0
	remaining = 128 - bufpos;

	/* Hash whole blocks */
	while (len >= remaining) {
		memcpy(ctx->wbuffer + bufpos, buffer, remaining);
		buffer = (const char *)buffer + remaining;
		len -= remaining;
		remaining = 128;
		bufpos = 0;
		sha512_process_block128(ctx);
	}

	/* Save last, partial blosk */
	memcpy(ctx->wbuffer + bufpos, buffer, len);
#else
	while (1) {
		remaining = 128 - bufpos;
		if (remaining > len)
			remaining = len;
		/* Copy data into aligned buffer */
		memcpy(ctx->wbuffer + bufpos, buffer, remaining);
		len -= remaining;
		buffer = (const char *)buffer + remaining;
		bufpos += remaining;
		/* clever way to do "if (bufpos != 128) break; ... ; bufpos = 0;" */
		bufpos -= 128;
		if (bufpos != 0)
			break;
		/* Buffer is filled up, process it */
		sha512_process_block128(ctx);
		/*bufpos = 0; - already is */
	}
#endif
}


/* Used also for sha256 */
void FAST_FUNC sha1_end(sha1_ctx_t *ctx, void *resbuf)
{
	unsigned bufpos = ctx->total64 & 63;

	/* Pad the buffer to the next 64-byte boundary with 0x80,0,0,0... */
	ctx->wbuffer[bufpos++] = 0x80;

	/* This loop iterates either once or twice, no more, no less */
	while (1) {
		unsigned pad = 64 - bufpos;
		memset(ctx->wbuffer + bufpos, 0, pad);
		/* Do we have enough space for the length count? */
		if (pad >= 8) {
			/* Store the 64-bit counter of bits in the buffer in BE format */
			uint64_t t = ctx->total64 << 3;
			t = hton64(t);
			/* wbuffer is suitably aligned for this */
			*(uint64_t *) (&ctx->wbuffer[64 - 8]) = t;
		}
		ctx->process_block(ctx);
		if (pad >= 8)
			break;
		bufpos = 0;
	}

	bufpos = (ctx->process_block == sha1_process_block64) ? 5 : 8;
	/* This way we do not impose alignment constraints on resbuf: */
	if (BB_LITTLE_ENDIAN) {
		unsigned i;
		for (i = 0; i < bufpos; ++i)
			ctx->hash[i] = htonl(ctx->hash[i]);
	}
	memcpy(resbuf, ctx->hash, sizeof(ctx->hash[0]) * bufpos);
}

void FAST_FUNC sha512_end(sha512_ctx_t *ctx, void *resbuf)
{
	unsigned bufpos = ctx->total64[0] & 127;

	/* Pad the buffer to the next 128-byte boundary with 0x80,0,0,0... */
	ctx->wbuffer[bufpos++] = 0x80;

	while (1) {
		unsigned pad = 128 - bufpos;
		memset(ctx->wbuffer + bufpos, 0, pad);
		if (pad >= 16) {
			/* Store the 128-bit counter of bits in the buffer in BE format */
			uint64_t t;
			t = ctx->total64[0] << 3;
			t = hton64(t);
			*(uint64_t *) (&ctx->wbuffer[128 - 8]) = t;
			t = (ctx->total64[1] << 3) | (ctx->total64[0] >> 61);
			t = hton64(t);
			*(uint64_t *) (&ctx->wbuffer[128 - 16]) = t;
		}
		sha512_process_block128(ctx);
		if (pad >= 16)
			break;
		bufpos = 0;
	}

	if (BB_LITTLE_ENDIAN) {
		unsigned i;
		for (i = 0; i < ARRAY_SIZE(ctx->hash); ++i)
			ctx->hash[i] = hton64(ctx->hash[i]);
	}
	memcpy(resbuf, ctx->hash, sizeof(ctx->hash));
}