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
|
// Copyright (C) 2011 Internet Systems Consortium, Inc. ("ISC")
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice appear in all copies.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
// AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
// OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
// PERFORMANCE OF THIS SOFTWARE.
#include <util/buffer.h>
#include <boost/noncopyable.hpp>
#include <cryptolink/cryptolink.h>
#ifndef _ISC_CRYPTO_HMAC_H
#define _ISC_CRYPTO_HMAC_H
namespace isc {
namespace cryptolink {
/// Forward declaration, pimpl style
class HMACImpl;
/// \brief HMAC support
///
/// This class is used to create and verify HMAC signatures. Instances
/// can be created with CryptoLink::createHMAC()
///
class HMAC : private boost::noncopyable {
private:
/// \brief Constructor from a secret and a hash algorithm
///
/// \exception UnsupportedAlgorithmException if the given algorithm
/// is unknown or not supported by the underlying library
/// \exception InvalidKeyLength if the given key secret_len is bad
/// \exception LibraryError if there was any unexpected exception
/// in the underlying library
///
/// Notes: if the secret is longer than the block size of its
/// algorithm, the constructor will run it through the hash
/// algorithm, and use the digest as the secret for this HMAC
/// operation
///
/// \param secret The secret to sign with
/// \param len The length of the secret
/// \param hash_algorithm The hash algorithm
HMAC(const void* secret, size_t secret_len,
const HashAlgorithm hash_algorithm);
friend HMAC* CryptoLink::createHMAC(const void*, size_t,
const HashAlgorithm);
public:
/// \brief Destructor
~HMAC();
/// \brief Returns the output size of the digest
///
/// \return output size of the digest
size_t getOutputLength() const;
/// \brief Add data to digest
///
/// \exception LibraryError if there was any unexpected exception
/// in the underlying library
///
/// \param data The data to add
/// \param len The size of the data
void update(const void* data, const size_t len);
/// \brief Calculate the final signature
///
/// The result will be appended to the given outputbuffer
///
/// \exception LibraryError if there was any unexpected exception
/// in the underlying library
///
/// \param result The OutputBuffer to append the result to
/// \param len The number of bytes from the result to copy. If this
/// value is smaller than the algorithms output size, the
/// result will be truncated. If this value is larger, or 0
/// (the default), it will be ignored
void sign(isc::util::OutputBuffer& result, size_t len = 0);
/// \brief Calculate the final signature
///
/// len bytes of data from the result will be copied to *result
/// If len is larger than the output size, only output_size bytes
/// will be copied. If it is smaller, the output will be truncated
///
/// \exception LibraryError if there was any unexpected exception
/// in the underlying library
///
/// At least len bytes of data must be available for writing at
/// result
void sign(void* result, size_t len);
/// \brief Calculate the final signatre
///
/// The result will be returned as a std::vector<uint8_t>
///
/// \exception LibraryError if there was any unexpected exception
/// in the underlying library
///
/// \param len The number of bytes from the result to copy. If this
/// value is smaller than the algorithms output size, the
/// result will be truncated. If this value is larger, or 0
/// (the default), it will be ignored
/// \return a vector containing the signature
std::vector<uint8_t> sign(size_t len = 0);
/// \brief Verify an existing signature
///
/// \exception LibraryError if there was any unexpected exception
/// in the underlying library
///
/// \param sig The signature to verify
/// \param len The length of the signature. If this is non-zero,
/// and smaller than the output length of the algorithm,
/// only len bytes will be checked
/// \return true if the signature is correct, false otherwise
bool verify(const void* sig, size_t len);
private:
HMACImpl* impl_;
};
/// \brief Create an HMAC signature for the given data
///
/// This is a convenience function that calculates the hmac signature,
/// given a fixed amount of data. Internally it does the same as
/// creating an HMAC object, feeding it the data, and calculating the
/// resulting signature.
///
/// \exception UnsupportedAlgorithm if the given algorithm is unknown
/// or not supported by the underlying library
/// \exception BadKey if the given key secret_len is bad
/// \exception LibraryError if there was any unexpected exception
/// in the underlying library
///
/// Notes: if the secret is longer than the block size of its
/// algorithm, the constructor will run it through the hash
/// algorithm, and use the digest as the secret for this HMAC
/// operation
///
/// \param data The data to sign
/// \param data_len The length of the data
/// \param secret The secret to sign with
/// \param secret_len The length of the secret
/// \param hash_algorithm The hash algorithm
/// \param result The signature will be appended to this buffer
/// \param len If this is non-zero and less than the output size,
/// the result will be truncated to len bytes
void signHMAC(const void* data,
const size_t data_len,
const void* secret,
size_t secret_len,
const HashAlgorithm hash_algorithm,
isc::util::OutputBuffer& result,
size_t len = 0);
/// \brief Verify an HMAC signature for the given data
///
/// This is a convenience function that verifies an hmac signature,
/// given a fixed amount of data. Internally it does the same as
/// creating an HMAC object, feeding it the data, and checking the
/// resulting signature.
///
/// \exception UnsupportedAlgorithm if the given algorithm is unknown
/// or not supported by the underlying library
/// \exception BadKey if the given key secret_len is bad
/// \exception LibraryError if there was any unexpected exception
/// in the underlying library
///
/// Notes: if the secret is longer than the block size of its
/// algorithm, the constructor will run it through the hash
/// algorithm, and use the digest as the secret for this HMAC
/// operation
///
/// \param data The data to verify
/// \param data_len The length of the data
/// \param secret The secret to sign with
/// \param secret_len The length of the secret
/// \param hash_algorithm The hash algorithm
/// \param sig The signature to verify
/// \param sig_len The length of the signature
/// \return True if the signature verifies, false if not
bool verifyHMAC(const void* data,
const size_t data_len,
const void* secret,
size_t secret_len,
const HashAlgorithm hash_algorithm,
const void* sig,
const size_t sig_len);
/// \brief Delete an HMAC object
void deleteHMAC(HMAC* hmac);
} // namespace cryptolink
} // namespace isc
#endif // __ISC_CRYPTO_HMAC
|