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
|
// Copyright (c) 2013 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 "net/quic/crypto/crypto_utils.h"
#include "crypto/hkdf.h"
#include "net/quic/crypto/crypto_handshake.h"
#include "net/quic/crypto/crypto_protocol.h"
#include "net/quic/crypto/quic_decrypter.h"
#include "net/quic/crypto/quic_encrypter.h"
#include "net/quic/crypto/quic_random.h"
#include "net/quic/quic_clock.h"
using base::StringPiece;
using std::string;
namespace net {
// static
bool CryptoUtils::FindMutualTag(const CryptoTagVector& our_tags_vector,
const CryptoTag* their_tags,
size_t num_their_tags,
Priority priority,
CryptoTag* out_result,
size_t* out_index) {
if (our_tags_vector.empty()) {
return false;
}
const size_t num_our_tags = our_tags_vector.size();
const CryptoTag* our_tags = &our_tags_vector[0];
size_t num_priority_tags, num_inferior_tags;
const CryptoTag* priority_tags;
const CryptoTag* inferior_tags;
if (priority == LOCAL_PRIORITY) {
num_priority_tags = num_our_tags;
priority_tags = our_tags;
num_inferior_tags = num_their_tags;
inferior_tags = their_tags;
} else {
num_priority_tags = num_their_tags;
priority_tags = their_tags;
num_inferior_tags = num_our_tags;
inferior_tags = our_tags;
}
for (size_t i = 0; i < num_priority_tags; i++) {
for (size_t j = 0; j < num_inferior_tags; j++) {
if (priority_tags[i] == inferior_tags[j]) {
*out_result = priority_tags[i];
if (out_index) {
if (priority == LOCAL_PRIORITY) {
*out_index = j;
} else {
*out_index = i;
}
}
return true;
}
}
}
return false;
}
void CryptoUtils::GenerateNonce(const QuicClock* clock,
QuicRandom* random_generator,
const string& orbit,
string* nonce) {
// a 4-byte timestamp + 28 random bytes.
nonce->reserve(kNonceSize);
nonce->resize(kNonceSize);
QuicTime::Delta now = clock->NowAsDeltaSinceUnixEpoch();
uint32 gmt_unix_time = now.ToSeconds();
memcpy(&(*nonce)[0], &gmt_unix_time, sizeof(gmt_unix_time));
size_t bytes_written = sizeof(gmt_unix_time);
if (orbit.size() == 8) {
memcpy(&(*nonce)[bytes_written], orbit.data(), orbit.size());
bytes_written += orbit.size();
}
random_generator->RandBytes(&(*nonce)[bytes_written],
kNonceSize - bytes_written);
}
void CryptoUtils::DeriveKeys(QuicCryptoNegotiatedParameters* params,
StringPiece nonce,
const string& hkdf_input,
Perspective perspective) {
params->encrypter.reset(QuicEncrypter::Create(params->aead));
params->decrypter.reset(QuicDecrypter::Create(params->aead));
size_t key_bytes = params->encrypter->GetKeySize();
size_t nonce_prefix_bytes = params->encrypter->GetNoncePrefixSize();
crypto::HKDF hkdf(params->premaster_secret, nonce,
hkdf_input, key_bytes, nonce_prefix_bytes);
if (perspective == SERVER) {
params->encrypter->SetKey(hkdf.server_write_key());
params->encrypter->SetNoncePrefix(hkdf.server_write_iv());
params->decrypter->SetKey(hkdf.client_write_key());
params->decrypter->SetNoncePrefix(hkdf.client_write_iv());
} else {
params->encrypter->SetKey(hkdf.client_write_key());
params->encrypter->SetNoncePrefix(hkdf.client_write_iv());
params->decrypter->SetKey(hkdf.server_write_key());
params->decrypter->SetNoncePrefix(hkdf.server_write_iv());
}
}
} // namespace net
|
