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
|
/*
* PKCS#11 ECDH
* (C) 2016 Daniel Neus, Sirrix AG
* (C) 2016 Philipp Weber, Sirrix AG
*
* Botan is released under the Simplified BSD License (see license.txt)
*/
#include <botan/p11_ecdh.h>
#if defined(BOTAN_HAS_ECDH)
#include <botan/internal/p11_mechanism.h>
#include <botan/ber_dec.h>
#include <botan/der_enc.h>
#include <botan/internal/algo_registry.h>
#include <botan/internal/pk_utils.h>
#include <botan/rng.h>
namespace Botan {
namespace PKCS11 {
ECDH_PublicKey PKCS11_ECDH_PublicKey::export_key() const
{
return ECDH_PublicKey(domain(), public_point());
}
ECDH_PrivateKey PKCS11_ECDH_PrivateKey::export_key() const
{
auto priv_key = get_attribute_value(AttributeType::Value);
Null_RNG rng;
return ECDH_PrivateKey(rng, domain(), BigInt::decode(priv_key));
}
secure_vector<byte> PKCS11_ECDH_PrivateKey::pkcs8_private_key() const
{
return export_key().pkcs8_private_key();
}
namespace {
class PKCS11_ECDH_KA_Operation : public PK_Ops::Key_Agreement
{
public:
typedef PKCS11_EC_PrivateKey Key_Type;
static PKCS11_ECDH_KA_Operation* make_ecdh(const Spec& spec, bool use_cofactor)
{
try
{
if(auto* key = dynamic_cast< const PKCS11_EC_PrivateKey* >(&spec.key()))
{
return new PKCS11_ECDH_KA_Operation(*key, spec.padding(), use_cofactor);
}
}
catch(...)
{
}
return nullptr;
}
PKCS11_ECDH_KA_Operation(const PKCS11_EC_PrivateKey& key, const std::string& kdf, bool use_cofactor)
: PK_Ops::Key_Agreement(), m_key(key), m_mechanism(MechanismWrapper::create_ecdh_mechanism(kdf, use_cofactor))
{}
/// The encoding in V2.20 was not specified and resulted in different implementations choosing different encodings.
/// Applications relying only on a V2.20 encoding (e.g. the DER variant) other than the one specified now (raw) may not work with all V2.30 compliant tokens.
secure_vector<byte> agree(size_t key_len, const byte other_key[], size_t other_key_len, const byte salt[],
size_t salt_len) override
{
std::vector<byte> der_encoded_other_key;
if(m_key.point_encoding() == PublicPointEncoding::Der)
{
der_encoded_other_key = DER_Encoder().encode(other_key, other_key_len, OCTET_STRING).get_contents_unlocked();
m_mechanism.set_ecdh_other_key(der_encoded_other_key.data(), der_encoded_other_key.size());
}
else
{
m_mechanism.set_ecdh_other_key(other_key, other_key_len);
}
if(salt != nullptr && salt_len > 0)
{
m_mechanism.set_ecdh_salt(salt, salt_len);
}
ObjectHandle secret_handle = 0;
AttributeContainer attributes;
attributes.add_bool(AttributeType::Sensitive, false);
attributes.add_bool(AttributeType::Extractable, true);
attributes.add_numeric(AttributeType::Class, static_cast< CK_OBJECT_CLASS >(ObjectClass::SecretKey));
attributes.add_numeric(AttributeType::KeyType, static_cast< CK_KEY_TYPE >(KeyType::GenericSecret));
attributes.add_numeric(AttributeType::ValueLen, key_len);
m_key.module()->C_DeriveKey(m_key.session().handle(), m_mechanism.data(), m_key.handle(), attributes.data(),
attributes.count(), &secret_handle);
Object secret_object(m_key.session(), secret_handle);
secure_vector<byte> secret = secret_object.get_attribute_value(AttributeType::Value);
if(secret.size() < key_len)
{
throw PKCS11_Error("ECDH key derivation secret length is too short");
}
secret.resize(key_len);
return secret;
}
private:
const PKCS11_EC_PrivateKey& m_key;
MechanismWrapper m_mechanism;
};
Algo_Registry<PK_Ops::Key_Agreement>::Add g_PKCS11_ECDH_KA_Operation_reg("ECDH",
std::bind(&PKCS11_ECDH_KA_Operation::make_ecdh, std::placeholders::_1, false), "pkcs11", BOTAN_PKCS11_ECDH_PRIO);
Algo_Registry<PK_Ops::Key_Agreement>::Add g_PKCS11_ECDHC_KA_Operation_reg("ECDHC",
std::bind(&PKCS11_ECDH_KA_Operation::make_ecdh, std::placeholders::_1, true), "pkcs11", BOTAN_PKCS11_ECDH_PRIO);
}
PKCS11_ECDH_KeyPair generate_ecdh_keypair(Session& session, const EC_PublicKeyGenerationProperties& pub_props,
const EC_PrivateKeyGenerationProperties& priv_props)
{
ObjectHandle pub_key_handle = 0;
ObjectHandle priv_key_handle = 0;
Mechanism mechanism = { static_cast< CK_MECHANISM_TYPE >(MechanismType::EcKeyPairGen), nullptr, 0 };
session.module()->C_GenerateKeyPair(session.handle(), &mechanism,
pub_props.data(), pub_props.count(), priv_props.data(), priv_props.count(),
&pub_key_handle, &priv_key_handle);
return std::make_pair(PKCS11_ECDH_PublicKey(session, pub_key_handle), PKCS11_ECDH_PrivateKey(session, priv_key_handle));
}
}
}
#endif
|
