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
|
/*
* (C) 2013 Jack Lloyd
* (C) 2016 Daniel Neus, Rohde & Schwarz Cybersecurity
*
* Botan is released under the Simplified BSD License (see license.txt)
*/
#ifndef BOTAN_GCM_GHASH_H_
#define BOTAN_GCM_GHASH_H_
#include <botan/sym_algo.h>
namespace Botan {
/**
* GCM's GHASH
* This is not intended for general use, but is exposed to allow
* shared code between GCM and GMAC
*/
class BOTAN_PUBLIC_API(2,0) GHASH final : public SymmetricAlgorithm
{
public:
void set_associated_data(const uint8_t ad[], size_t ad_len);
secure_vector<uint8_t> BOTAN_DEPRECATED("Use other impl")
nonce_hash(const uint8_t nonce[], size_t nonce_len)
{
secure_vector<uint8_t> y0(GCM_BS);
nonce_hash(y0, nonce, nonce_len);
return y0;
}
void nonce_hash(secure_vector<uint8_t>& y0, const uint8_t nonce[], size_t len);
void start(const uint8_t nonce[], size_t len);
/*
* Assumes input len is multiple of 16
*/
void update(const uint8_t in[], size_t len);
/*
* Incremental update of associated data
*/
void update_associated_data(const uint8_t ad[], size_t len);
secure_vector<uint8_t> BOTAN_DEPRECATED("Use version taking output params") final()
{
secure_vector<uint8_t> mac(GCM_BS);
final(mac.data(), mac.size());
return mac;
}
void final(uint8_t out[], size_t out_len);
Key_Length_Specification key_spec() const override
{ return Key_Length_Specification(16); }
void clear() override;
void reset();
std::string name() const override { return "GHASH"; }
std::string provider() const;
void ghash_update(secure_vector<uint8_t>& x,
const uint8_t input[], size_t input_len);
void add_final_block(secure_vector<uint8_t>& x,
size_t ad_len, size_t pt_len);
private:
void key_schedule(const uint8_t key[], size_t key_len) override;
void gcm_multiply(secure_vector<uint8_t>& x,
const uint8_t input[],
size_t blocks);
static const size_t GCM_BS = 16;
secure_vector<uint8_t> m_H;
secure_vector<uint8_t> m_H_ad;
secure_vector<uint8_t> m_ghash;
secure_vector<uint8_t> m_nonce;
secure_vector<uint64_t> m_HM;
secure_vector<uint64_t> m_H_pow;
size_t m_ad_len = 0;
size_t m_text_len = 0;
};
}
#endif
|
