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
|
/*
* (C) 1999-2010,2015 Jack Lloyd
*
* Botan is released under the Simplified BSD License (see license.txt)
*/
#include <botan/pubkey.h>
#include <botan/internal/algo_registry.h>
#include <botan/der_enc.h>
#include <botan/ber_dec.h>
#include <botan/bigint.h>
namespace Botan {
namespace {
template<typename T, typename Key>
T* get_pk_op(const std::string& what, const Key& key, const std::string& pad,
const std::string& provider = "")
{
if(T* p = Algo_Registry<T>::global_registry().make(typename T::Spec(key, pad), provider))
return p;
const std::string err = what + " with " + key.algo_name() + "/" + pad + " not supported";
if(provider != "")
throw Lookup_Error(err + " with provider " + provider);
else
throw Lookup_Error(err);
}
}
PK_Encryptor_EME::PK_Encryptor_EME(const Public_Key& key,
const std::string& padding,
const std::string& provider)
{
m_op.reset(get_pk_op<PK_Ops::Encryption>("Encryption", key, padding, provider));
}
std::vector<byte>
PK_Encryptor_EME::enc(const byte in[], size_t length, RandomNumberGenerator& rng) const
{
return unlock(m_op->encrypt(in, length, rng));
}
size_t PK_Encryptor_EME::maximum_input_size() const
{
return m_op->max_input_bits() / 8;
}
PK_Decryptor_EME::PK_Decryptor_EME(const Private_Key& key, const std::string& padding,
const std::string& provider)
{
m_op.reset(get_pk_op<PK_Ops::Decryption>("Decryption", key, padding, provider));
}
secure_vector<byte> PK_Decryptor_EME::dec(const byte msg[], size_t length) const
{
return m_op->decrypt(msg, length);
}
PK_KEM_Encryptor::PK_KEM_Encryptor(const Public_Key& key,
const std::string& param,
const std::string& provider)
{
m_op.reset(get_pk_op<PK_Ops::KEM_Encryption>("KEM", key, param, provider));
}
void PK_KEM_Encryptor::encrypt(secure_vector<byte>& out_encapsulated_key,
secure_vector<byte>& out_shared_key,
size_t desired_shared_key_len,
Botan::RandomNumberGenerator& rng,
const uint8_t salt[],
size_t salt_len)
{
m_op->kem_encrypt(out_encapsulated_key,
out_shared_key,
desired_shared_key_len,
rng,
salt,
salt_len);
}
PK_KEM_Decryptor::PK_KEM_Decryptor(const Private_Key& key,
const std::string& param,
const std::string& provider)
{
m_op.reset(get_pk_op<PK_Ops::KEM_Decryption>("KEM", key, param, provider));
}
secure_vector<byte> PK_KEM_Decryptor::decrypt(const byte encap_key[],
size_t encap_key_len,
size_t desired_shared_key_len,
const uint8_t salt[],
size_t salt_len)
{
return m_op->kem_decrypt(encap_key, encap_key_len,
desired_shared_key_len,
salt, salt_len);
}
PK_Key_Agreement::PK_Key_Agreement(const Private_Key& key,
const std::string& kdf,
const std::string& provider)
{
m_op.reset(get_pk_op<PK_Ops::Key_Agreement>("Key agreement", key, kdf, provider));
}
SymmetricKey PK_Key_Agreement::derive_key(size_t key_len,
const byte in[], size_t in_len,
const byte salt[],
size_t salt_len) const
{
return m_op->agree(key_len, in, in_len, salt, salt_len);
}
namespace {
std::vector<byte> der_encode_signature(const std::vector<byte>& sig, size_t parts)
{
if(sig.size() % parts)
throw Encoding_Error("PK_Signer: strange signature size found");
const size_t SIZE_OF_PART = sig.size() / parts;
std::vector<BigInt> sig_parts(parts);
for(size_t j = 0; j != sig_parts.size(); ++j)
sig_parts[j].binary_decode(&sig[SIZE_OF_PART*j], SIZE_OF_PART);
return DER_Encoder()
.start_cons(SEQUENCE)
.encode_list(sig_parts)
.end_cons()
.get_contents_unlocked();
}
std::vector<byte> der_decode_signature(const byte sig[], size_t len,
size_t part_size, size_t parts)
{
std::vector<byte> real_sig;
BER_Decoder decoder(sig, len);
BER_Decoder ber_sig = decoder.start_cons(SEQUENCE);
size_t count = 0;
while(ber_sig.more_items())
{
BigInt sig_part;
ber_sig.decode(sig_part);
real_sig += BigInt::encode_1363(sig_part, part_size);
++count;
}
if(count != parts)
throw Decoding_Error("PK_Verifier: signature size invalid");
return real_sig;
}
}
PK_Signer::PK_Signer(const Private_Key& key,
const std::string& emsa,
Signature_Format format,
const std::string& provider)
{
m_op.reset(get_pk_op<PK_Ops::Signature>("Signing", key, emsa, provider));
m_sig_format = format;
}
void PK_Signer::update(const byte in[], size_t length)
{
m_op->update(in, length);
}
std::vector<byte> PK_Signer::signature(RandomNumberGenerator& rng)
{
const std::vector<byte> plain_sig = unlock(m_op->sign(rng));
const size_t parts = m_op->message_parts();
if(parts == 1 || m_sig_format == IEEE_1363)
return plain_sig;
else if(m_sig_format == DER_SEQUENCE)
return der_encode_signature(plain_sig, parts);
else
throw Encoding_Error("PK_Signer: Unknown signature format " +
std::to_string(m_sig_format));
}
PK_Verifier::PK_Verifier(const Public_Key& key,
const std::string& emsa_name,
Signature_Format format,
const std::string& provider)
{
m_op.reset(get_pk_op<PK_Ops::Verification>("Verification", key, emsa_name, provider));
m_sig_format = format;
}
void PK_Verifier::set_input_format(Signature_Format format)
{
if(m_op->message_parts() == 1 && format != IEEE_1363)
throw Invalid_State("PK_Verifier: This algorithm always uses IEEE 1363");
m_sig_format = format;
}
bool PK_Verifier::verify_message(const byte msg[], size_t msg_length,
const byte sig[], size_t sig_length)
{
update(msg, msg_length);
return check_signature(sig, sig_length);
}
void PK_Verifier::update(const byte in[], size_t length)
{
m_op->update(in, length);
}
bool PK_Verifier::check_signature(const byte sig[], size_t length)
{
try {
if(m_sig_format == IEEE_1363)
{
return m_op->is_valid_signature(sig, length);
}
else if(m_sig_format == DER_SEQUENCE)
{
std::vector<byte> real_sig = der_decode_signature(sig, length,
m_op->message_part_size(),
m_op->message_parts());
return m_op->is_valid_signature(real_sig.data(), real_sig.size());
}
else
throw Decoding_Error("PK_Verifier: Unknown signature format " +
std::to_string(m_sig_format));
}
catch(Invalid_Argument) { return false; }
}
}
|
