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
|
/*
* OpenPGP PBKDF
* (C) 1999-2007,2017 Jack Lloyd
*
* Distributed under the terms of the Botan license
*/
#ifndef BOTAN_OPENPGP_S2K_H__
#define BOTAN_OPENPGP_S2K_H__
#include <botan/pbkdf.h>
#include <botan/hash.h>
namespace Botan {
/**
* OpenPGP's S2K
*
* See RFC 4880 sections 3.7.1.1, 3.7.1.2, and 3.7.1.3
* If the salt is empty and iterations == 1, "simple" S2K is used
* If the salt is non-empty and iterations == 1, "salted" S2K is used
* If the salt is non-empty and iterations > 1, "iterated" S2K is used
*
* If iterations == 0 and msec.count() > 0, "iterated" S2K is assumed,
* and the number of iterations performed is returned.
*
* Note that unlike PBKDF2, OpenPGP S2K's "iterations" are defined as
* the number of bytes hashed.
*/
class BOTAN_DLL OpenPGP_S2K final : public PBKDF
{
public:
/**
* @param hash_in the hash function to use
*/
explicit OpenPGP_S2K(HashFunction* hash) : m_hash(hash) {}
std::string name() const override
{
return "OpenPGP-S2K(" + m_hash->name() + ")";
}
PBKDF* clone() const
{
return new OpenPGP_S2K(m_hash->clone());
}
size_t pbkdf(uint8_t output_buf[], size_t output_len,
const std::string& passphrase,
const uint8_t salt[], size_t salt_len,
size_t iterations,
std::chrono::milliseconds msec) const override;
/**
* RFC 4880 encodes the iteration count to a single-byte value
*/
static uint8_t encode_count(size_t iterations);
static size_t decode_count(uint8_t encoded_iter);
private:
std::unique_ptr<HashFunction> m_hash;
};
}
#endif
|
