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
|
// Copyright (c) 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "crypto/symmetric_key.h"
#include <nss.h>
#include <pk11pub.h>
#include "base/logging.h"
#include "crypto/nss_util.h"
namespace crypto {
SymmetricKey::~SymmetricKey() {}
// static
SymmetricKey* SymmetricKey::GenerateRandomKey(Algorithm algorithm,
size_t key_size_in_bits) {
DCHECK_EQ(AES, algorithm);
EnsureNSSInit();
if (key_size_in_bits == 0)
return NULL;
ScopedPK11Slot slot(PK11_GetBestSlot(CKM_AES_KEY_GEN, NULL));
if (!slot.get())
return NULL;
PK11SymKey* sym_key = PK11_KeyGen(slot.get(), CKM_AES_KEY_GEN, NULL,
key_size_in_bits / 8, NULL);
if (!sym_key)
return NULL;
return new SymmetricKey(sym_key);
}
// static
SymmetricKey* SymmetricKey::DeriveKeyFromPassword(Algorithm algorithm,
const std::string& password,
const std::string& salt,
size_t iterations,
size_t key_size_in_bits) {
EnsureNSSInit();
if (salt.empty() || iterations == 0 || key_size_in_bits == 0)
return NULL;
SECItem password_item;
password_item.type = siBuffer;
password_item.data = reinterpret_cast<unsigned char*>(
const_cast<char *>(password.data()));
password_item.len = password.size();
SECItem salt_item;
salt_item.type = siBuffer;
salt_item.data = reinterpret_cast<unsigned char*>(
const_cast<char *>(salt.data()));
salt_item.len = salt.size();
SECOidTag cipher_algorithm =
algorithm == AES ? SEC_OID_AES_256_CBC : SEC_OID_HMAC_SHA1;
ScopedSECAlgorithmID alg_id(PK11_CreatePBEV2AlgorithmID(SEC_OID_PKCS5_PBKDF2,
cipher_algorithm,
SEC_OID_HMAC_SHA1,
key_size_in_bits / 8,
iterations,
&salt_item));
if (!alg_id.get())
return NULL;
ScopedPK11Slot slot(PK11_GetBestSlot(SEC_OID_PKCS5_PBKDF2, NULL));
if (!slot.get())
return NULL;
PK11SymKey* sym_key = PK11_PBEKeyGen(slot.get(), alg_id.get(), &password_item,
PR_FALSE, NULL);
if (!sym_key)
return NULL;
return new SymmetricKey(sym_key);
}
// static
SymmetricKey* SymmetricKey::Import(Algorithm algorithm,
const std::string& raw_key) {
CK_MECHANISM_TYPE cipher =
algorithm == AES ? CKM_AES_CBC : CKM_SHA_1_HMAC;
SECItem key_item;
key_item.type = siBuffer;
key_item.data = reinterpret_cast<unsigned char*>(
const_cast<char *>(raw_key.data()));
key_item.len = raw_key.size();
ScopedPK11Slot slot(PK11_GetBestSlot(cipher, NULL));
if (!slot.get())
return NULL;
// The exact value of the |origin| argument doesn't matter to NSS as long as
// it's not PK11_OriginFortezzaHack, so we pass PK11_OriginUnwrap as a
// placeholder.
PK11SymKey* sym_key = PK11_ImportSymKey(slot.get(), cipher, PK11_OriginUnwrap,
CKA_ENCRYPT, &key_item, NULL);
if (!sym_key)
return NULL;
return new SymmetricKey(sym_key);
}
bool SymmetricKey::GetRawKey(std::string* raw_key) {
SECStatus rv = PK11_ExtractKeyValue(key_.get());
if (SECSuccess != rv)
return false;
SECItem* key_item = PK11_GetKeyData(key_.get());
if (!key_item)
return false;
raw_key->assign(reinterpret_cast<char*>(key_item->data), key_item->len);
return true;
}
#if defined(OS_CHROMEOS)
// static
SymmetricKey* SymmetricKey::CreateFromKey(PK11SymKey* key) {
return new SymmetricKey(key);
}
#endif
SymmetricKey::SymmetricKey(PK11SymKey* key) : key_(key) {
DCHECK(key);
}
} // namespace crypto
|
