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
|
/* See LICENSE file for copyright and license details. */
#include "common.h"
#if defined(__clang__)
# pragma clang diagnostic ignored "-Wcast-align"
#endif
/**
* Unmarshal a `struct libkeccak_hmac_state` from a buffer
*
* @param state The slot for the unmarshalled state, must not be
* initialised (memory leak otherwise), can be `NULL`
* @param data_ The input buffer
* @return The number of bytes read from `data`, 0 on error
*/
size_t
libkeccak_hmac_unmarshal(struct libkeccak_hmac_state *restrict state, const void *restrict data_)
{
const unsigned char *restrict data = data_;
size_t parsed, size, i;
state->key_opad = NULL;
state->key_ipad = NULL;
parsed = libkeccak_state_unmarshal(state ? &state->sponge : NULL, data);
if (!parsed)
return 0;
data += parsed;
__builtin_memcpy(&size, data, sizeof(size));
data += sizeof(size_t);
if (state)
size = state->key_length;
size = (state->key_length + 7) >> 3;
if (state) {
state->key_opad = malloc(2 * size);
if (!state->key_opad) {
libkeccak_state_destroy(&state->sponge);
return 0;
}
memcpy(state->key_opad, data, size);
data += size;
if (data[0]) {
state->key_ipad = &state->key_opad[size];
memcpy(state->key_ipad, state->key_opad, size);
for (i = 0; i < size; i++)
state->key_ipad[i] ^= (char)(HMAC_OUTER_PAD ^ HMAC_INNER_PAD);
}
state->leftover = data[1];
state->buffer = NULL;
state->buffer_size = 0;
}
return parsed + sizeof(size_t) + size + 2 * sizeof(char);
}
|