blob: 1de27c9acb63be634be38d0ff51ae14344330047 (
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
|
/*
* PBKDF2
* (C) 1999-2007 Jack Lloyd
*
* Distributed under the terms of the Botan license
*/
#include <botan/pbkdf2.h>
#include <botan/loadstor.h>
#include <botan/xor_buf.h>
namespace Botan {
/*
* Return a PKCS#5 PBKDF2 derived key
*/
OctetString PKCS5_PBKDF2::derive(u32bit key_len,
const std::string& passphrase,
const byte salt[], u32bit salt_size,
u32bit iterations) const
{
if(iterations == 0)
throw Invalid_Argument("PKCS#5 PBKDF2: Invalid iteration count");
if(passphrase.length() == 0)
throw Invalid_Argument("PKCS#5 PBKDF2: Empty passphrase is invalid");
mac->set_key(reinterpret_cast<const byte*>(passphrase.data()),
passphrase.length());
SecureVector<byte> key(key_len);
byte* T = key.begin();
u32bit counter = 1;
while(key_len)
{
u32bit T_size = std::min(mac->OUTPUT_LENGTH, key_len);
SecureVector<byte> U(mac->OUTPUT_LENGTH);
mac->update(salt, salt_size);
for(u32bit j = 0; j != 4; ++j)
mac->update(get_byte(j, counter));
mac->final(U);
xor_buf(T, U, T_size);
for(u32bit j = 1; j != iterations; ++j)
{
mac->update(U);
mac->final(U);
xor_buf(T, U, T_size);
}
key_len -= T_size;
T += T_size;
++counter;
}
return key;
}
/*
* Return the name of this type
*/
std::string PKCS5_PBKDF2::name() const
{
return "PBKDF2(" + mac->name() + ")";
}
S2K* PKCS5_PBKDF2::clone() const
{
return new PKCS5_PBKDF2(mac->clone());
}
/*
* PKCS5_PBKDF2 Constructor
*/
PKCS5_PBKDF2::PKCS5_PBKDF2(MessageAuthenticationCode* m) : mac(m) {}
PKCS5_PBKDF2::~PKCS5_PBKDF2() { delete mac; }
}
|
