aboutsummaryrefslogtreecommitdiffstats
path: root/update.c
blob: 3263b6246e956d1213dd3920b3ce94566b67491f (plain) (blame)
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
/* See LICENSE file for copyright and license details. */
#include "common.h"


/**
 * Unified implementation (what can unified without performance impact)
 * of the chunk processing for all SHA-2 functions
 * 
 * @param  A       Wordsize-dependent constant, take a look at the code
 * @param  B       Wordsize-dependent constant, take a look at the code
 * @param  C       Wordsize-dependent constant, take a look at the code
 * @param  D       Wordsize-dependent constant, take a look at the code
 * @param  E       Wordsize-dependent constant, take a look at the code
 * @param  F       Wordsize-dependent constant, take a look at the code
 * @param  G       Wordsize-dependent constant, take a look at the code
 * @param  H       Wordsize-dependent constant, take a look at the code
 * @param  I       Wordsize-dependent constant, take a look at the code
 * @param  J       Wordsize-dependent constant, take a look at the code
 * @param  K       Wordsize-dependent constant, take a look at the code
 * @param  L       Wordsize-dependent constant, take a look at the code
 * @param  WORD_T  `__typeof()` on any wordsize-dependent variable, with exact size
 * @param  k       Round constants
 * @param  w       Words
 * @param  h       Hash values
 * @param  work_h  Space for temporary hash values
 */
#define SHA2_IMPLEMENTATION(A, B, C, D, E, F, G, H, I, J, K, L, WORD_T, k, w, h, work_h)\
	memcpy(work_h, h, sizeof(work_h));\
	\
	memset(w, 0, 16 * sizeof(*(w)));\
	for (i = 0; i < 16; i++)\
		for (j = 0; j < sizeof(WORD_T); j++)\
			w[i] |= ((WORD_T)(state->chunk[(i + 1) * sizeof(WORD_T) - j - 1])) << (j << 3);\
	\
	for (i = 16; i < sizeof(k) / sizeof(*(k)); i++)	{\
		w[i] = w[i - 16] + w[i - 7];\
		w[i] += ROTR(w[i - 15], A) ^ ROTR(w[i - 15], B) ^ (w[i - 15] >> (C));\
		w[i] += ROTR(w[i - 2], D) ^ ROTR(w[i - 2], E) ^ (w[i - 2] >> (F));\
	}\
	\
	for (i = 0; i < sizeof(k) / sizeof(*(k)); i++) {\
		s1 = (work_h[4] & work_h[5]) ^ (work_h[6] & ~(work_h[4]));\
		s1 += work_h[7] + k[i] + w[i];\
		s0 = (work_h[0] & work_h[1]) ^ (work_h[0] & work_h[2]) ^ (work_h[1] & work_h[2]);\
		s1 += ROTR(work_h[4], G) ^ ROTR(work_h[4], H) ^ ROTR(work_h[4], I);\
		s0 += ROTR(work_h[0], J) ^ ROTR(work_h[0], K) ^ ROTR(work_h[0], L);\
		\
		memmove(work_h + 1, work_h, 7 * sizeof(*(work_h)));\
		work_h[4] += s1;\
		work_h[0] = s1 + s0;\
	}\
	\
	for (i = 0; i < 8; i++)\
		h[i] += work_h[i]


/**
 * Process a chunk using SHA-256
 * 
 * @param  state  The hashing state
 */
#if defined(__GNUC__)
__attribute__((__nonnull__, __nothrow__))
#endif
static void
process256(struct libsha2_state *restrict state)
{
	uint32_t s0, s1;
	size_t i, j;
#if defined(__GNUC__)
# pragma GCC diagnostic push
# pragma GCC diagnostic ignored "-Wmemset-elt-size"
#endif
#define ROTR(X, N) (((X) >> (N)) | ((X) << ((sizeof(uint32_t) * 8) - (N))))
	SHA2_IMPLEMENTATION(7, 18, 3, 17, 19, 10, 6, 11, 25, 2, 13, 22, uint32_t,
	                    state->k.b32, state->w.b32, state->h.b32, state->work_h.b32);
#undef ROTR
#if defined(__GNUC__)
# pragma GCC diagnostic pop
#endif
}


/**
 * Process a chunk using SHA-512
 * 
 * @param  state  The hashing state
 */
#if defined(__GNUC__)
__attribute__((__nonnull__, __nothrow__))
#endif
static void
process512(struct libsha2_state *restrict state)
{
	uint64_t s0, s1;
	size_t i, j;
#define ROTR(X, N) (((X) >> (N)) | ((X) << ((sizeof(uint64_t) * 8) - (N))))
	SHA2_IMPLEMENTATION(1, 8, 7, 19, 61, 6, 14, 18, 41, 28, 34, 39, uint64_t,
	                    state->k.b64, state->w.b64, state->h.b64, state->work_h.b64);
#undef ROTR
}


/**
 * Absorb more of the message
 * 
 * @param  state    The hashing state
 * @param  message  The message, in bits, must be equivalent to 0 modulus 8
 * @param  msglen   The length of the message
 */
void
libsha2_update(struct libsha2_state *restrict state, const char *restrict message, size_t msglen)
{
	size_t n, off, mlen;

	msglen /= 8;
	mlen = state->message_size / 8;

	while (msglen) {
		off = mlen % state->chunk_size;
		n = state->chunk_size - off;
		n = n < msglen ? n : msglen;
		memcpy(state->chunk + off, message, n);
		if (off + n == state->chunk_size) {
			if (state->algorithm <= LIBSHA2_256)
				process256(state);
			else
				process512(state);
		}
		message += n, mlen += n, msglen -= n;
	}

	state->message_size = mlen * 8;
}