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
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
|
/*
* PBKDF
* (C) 1999-2007,2012,2015 Jack Lloyd
*
* Botan is released under the Simplified BSD License (see license.txt)
*/
#ifndef BOTAN_PBKDF_H_
#define BOTAN_PBKDF_H_
#include <botan/symkey.h>
#include <chrono>
namespace Botan {
/**
* Base class for PBKDF (password based key derivation function)
* implementations. Converts a password into a key using a salt
* and iterated hashing to make brute force attacks harder.
*
* Starting in 2.8 this functionality is also offered by PasswordHash.
* The PBKDF interface may be removed in a future release.
*/
class BOTAN_PUBLIC_API(2,0) PBKDF
{
public:
/**
* Create an instance based on a name
* If provider is empty then best available is chosen.
* @param algo_spec algorithm name
* @param provider provider implementation to choose
* @return a null pointer if the algo/provider combination cannot be found
*/
static std::unique_ptr<PBKDF> create(const std::string& algo_spec,
const std::string& provider = "");
/**
* Create an instance based on a name, or throw if the
* algo/provider combination cannot be found. If provider is
* empty then best available is chosen.
*/
static std::unique_ptr<PBKDF>
create_or_throw(const std::string& algo_spec,
const std::string& provider = "");
/**
* @return list of available providers for this algorithm, empty if not available
*/
static std::vector<std::string> providers(const std::string& algo_spec);
/**
* @return new instance of this same algorithm
*/
virtual PBKDF* clone() const = 0;
/**
* @return name of this PBKDF
*/
virtual std::string name() const = 0;
virtual ~PBKDF() = default;
/**
* Derive a key from a passphrase for a number of iterations
* specified by either iterations or if iterations == 0 then
* running until msec time has elapsed.
*
* @param out buffer to store the derived key, must be of out_len bytes
* @param out_len the desired length of the key to produce
* @param passphrase the password to derive the key from
* @param salt a randomly chosen salt
* @param salt_len length of salt in bytes
* @param iterations the number of iterations to use (use 10K or more)
* @param msec if iterations is zero, then instead the PBKDF is
* run until msec milliseconds has passed.
* @return the number of iterations performed
*/
virtual size_t pbkdf(uint8_t out[], size_t out_len,
const std::string& passphrase,
const uint8_t salt[], size_t salt_len,
size_t iterations,
std::chrono::milliseconds msec) const = 0;
/**
* Derive a key from a passphrase for a number of iterations.
*
* @param out buffer to store the derived key, must be of out_len bytes
* @param out_len the desired length of the key to produce
* @param passphrase the password to derive the key from
* @param salt a randomly chosen salt
* @param salt_len length of salt in bytes
* @param iterations the number of iterations to use (use 10K or more)
*/
void pbkdf_iterations(uint8_t out[], size_t out_len,
const std::string& passphrase,
const uint8_t salt[], size_t salt_len,
size_t iterations) const;
/**
* Derive a key from a passphrase, running until msec time has elapsed.
*
* @param out buffer to store the derived key, must be of out_len bytes
* @param out_len the desired length of the key to produce
* @param passphrase the password to derive the key from
* @param salt a randomly chosen salt
* @param salt_len length of salt in bytes
* @param msec if iterations is zero, then instead the PBKDF is
* run until msec milliseconds has passed.
* @param iterations set to the number iterations executed
*/
void pbkdf_timed(uint8_t out[], size_t out_len,
const std::string& passphrase,
const uint8_t salt[], size_t salt_len,
std::chrono::milliseconds msec,
size_t& iterations) const;
/**
* Derive a key from a passphrase for a number of iterations.
*
* @param out_len the desired length of the key to produce
* @param passphrase the password to derive the key from
* @param salt a randomly chosen salt
* @param salt_len length of salt in bytes
* @param iterations the number of iterations to use (use 10K or more)
* @return the derived key
*/
secure_vector<uint8_t> pbkdf_iterations(size_t out_len,
const std::string& passphrase,
const uint8_t salt[], size_t salt_len,
size_t iterations) const;
/**
* Derive a key from a passphrase, running until msec time has elapsed.
*
* @param out_len the desired length of the key to produce
* @param passphrase the password to derive the key from
* @param salt a randomly chosen salt
* @param salt_len length of salt in bytes
* @param msec if iterations is zero, then instead the PBKDF is
* run until msec milliseconds has passed.
* @param iterations set to the number iterations executed
* @return the derived key
*/
secure_vector<uint8_t> pbkdf_timed(size_t out_len,
const std::string& passphrase,
const uint8_t salt[], size_t salt_len,
std::chrono::milliseconds msec,
size_t& iterations) const;
// Following kept for compat with 1.10:
/**
* Derive a key from a passphrase
* @param out_len the desired length of the key to produce
* @param passphrase the password to derive the key from
* @param salt a randomly chosen salt
* @param salt_len length of salt in bytes
* @param iterations the number of iterations to use (use 10K or more)
*/
OctetString derive_key(size_t out_len,
const std::string& passphrase,
const uint8_t salt[], size_t salt_len,
size_t iterations) const
{
return pbkdf_iterations(out_len, passphrase, salt, salt_len, iterations);
}
/**
* Derive a key from a passphrase
* @param out_len the desired length of the key to produce
* @param passphrase the password to derive the key from
* @param salt a randomly chosen salt
* @param iterations the number of iterations to use (use 10K or more)
*/
template<typename Alloc>
OctetString derive_key(size_t out_len,
const std::string& passphrase,
const std::vector<uint8_t, Alloc>& salt,
size_t iterations) const
{
return pbkdf_iterations(out_len, passphrase, salt.data(), salt.size(), iterations);
}
/**
* Derive a key from a passphrase
* @param out_len the desired length of the key to produce
* @param passphrase the password to derive the key from
* @param salt a randomly chosen salt
* @param salt_len length of salt in bytes
* @param msec is how long to run the PBKDF
* @param iterations is set to the number of iterations used
*/
OctetString derive_key(size_t out_len,
const std::string& passphrase,
const uint8_t salt[], size_t salt_len,
std::chrono::milliseconds msec,
size_t& iterations) const
{
return pbkdf_timed(out_len, passphrase, salt, salt_len, msec, iterations);
}
/**
* Derive a key from a passphrase using a certain amount of time
* @param out_len the desired length of the key to produce
* @param passphrase the password to derive the key from
* @param salt a randomly chosen salt
* @param msec is how long to run the PBKDF
* @param iterations is set to the number of iterations used
*/
template<typename Alloc>
OctetString derive_key(size_t out_len,
const std::string& passphrase,
const std::vector<uint8_t, Alloc>& salt,
std::chrono::milliseconds msec,
size_t& iterations) const
{
return pbkdf_timed(out_len, passphrase, salt.data(), salt.size(), msec, iterations);
}
};
/*
* Compatability typedef
*/
typedef PBKDF S2K;
/**
* Password based key derivation function factory method
* @param algo_spec the name of the desired PBKDF algorithm
* @param provider the provider to use
* @return pointer to newly allocated object of that type
*/
inline PBKDF* get_pbkdf(const std::string& algo_spec,
const std::string& provider = "")
{
return PBKDF::create_or_throw(algo_spec, provider).release();
}
inline PBKDF* get_s2k(const std::string& algo_spec)
{
return get_pbkdf(algo_spec);
}
}
#endif
|
