1 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "net/quic/crypto/common_cert_set.h"
6
7 #include "base/basictypes.h"
8 #include "base/logging.h"
9 #include "base/memory/singleton.h"
10 #include "net/quic/quic_utils.h"
11
12 using base::StringPiece;
13
14 namespace net {
15
16 namespace common_cert_set_0 {
17 #include "net/quic/crypto/common_cert_set_0.c"
18 }
19
20 namespace {
21
22 struct CertSet {
23 // num_certs contains the number of certificates in this set.
24 size_t num_certs;
25 // certs is an array of |num_certs| pointers to the DER encoded certificates.
26 const unsigned char* const* certs;
27 // lens is an array of |num_certs| integers describing the length, in bytes,
28 // of each certificate.
29 const size_t* lens;
30 // hash contains the 64-bit, FNV-1a hash of this set.
31 uint64 hash;
32 };
33
34 const CertSet kSets[] = {
35 {
36 common_cert_set_0::kNumCerts,
37 common_cert_set_0::kCerts,
38 common_cert_set_0::kLens,
39 common_cert_set_0::kHash,
40 },
41 };
42
43 const uint64 kSetHashes[] = {
44 common_cert_set_0::kHash,
45 };
46
47 // Compare returns a value less than, equal to or greater than zero if |a| is
48 // lexicographically less than, equal to or greater than |b|, respectively.
Compare(StringPiece a,const unsigned char * b,size_t b_len)49 int Compare(StringPiece a, const unsigned char* b, size_t b_len) {
50 size_t len = a.size();
51 if (len > b_len) {
52 len = b_len;
53 }
54 int n = memcmp(a.data(), b, len);
55 if (n != 0) {
56 return n;
57 }
58
59 if (a.size() < b_len) {
60 return -1;
61 } else if (a.size() > b_len) {
62 return 1;
63 }
64 return 0;
65 }
66
67 // CommonCertSetsQUIC implements the CommonCertSets interface using the default
68 // certificate sets.
69 class CommonCertSetsQUIC : public CommonCertSets {
70 public:
71 // CommonCertSets interface.
GetCommonHashes() const72 virtual StringPiece GetCommonHashes() const OVERRIDE {
73 return StringPiece(reinterpret_cast<const char*>(kSetHashes),
74 sizeof(uint64) * arraysize(kSetHashes));
75 }
76
GetCert(uint64 hash,uint32 index) const77 virtual StringPiece GetCert(uint64 hash, uint32 index) const OVERRIDE {
78 for (size_t i = 0; i < arraysize(kSets); i++) {
79 if (kSets[i].hash == hash) {
80 if (index < kSets[i].num_certs) {
81 return StringPiece(
82 reinterpret_cast<const char*>(kSets[i].certs[index]),
83 kSets[i].lens[index]);
84 }
85 break;
86 }
87 }
88
89 return StringPiece();
90 }
91
MatchCert(StringPiece cert,StringPiece common_set_hashes,uint64 * out_hash,uint32 * out_index) const92 virtual bool MatchCert(StringPiece cert, StringPiece common_set_hashes,
93 uint64* out_hash, uint32* out_index) const OVERRIDE {
94 if (common_set_hashes.size() % sizeof(uint64) != 0) {
95 return false;
96 }
97
98 for (size_t i = 0; i < common_set_hashes.size() / sizeof(uint64); i++) {
99 uint64 hash;
100 memcpy(&hash, common_set_hashes.data() + i * sizeof(uint64),
101 sizeof(uint64));
102
103 for (size_t j = 0; j < arraysize(kSets); j++) {
104 if (kSets[j].hash != hash) {
105 continue;
106 }
107
108 if (kSets[j].num_certs == 0) {
109 continue;
110 }
111
112 // Binary search for a matching certificate.
113 size_t min = 0;
114 size_t max = kSets[j].num_certs - 1;
115 while (max >= min) {
116 size_t mid = min + ((max - min) / 2);
117 int n = Compare(cert, kSets[j].certs[mid], kSets[j].lens[mid]);
118 if (n < 0) {
119 if (mid == 0) {
120 break;
121 }
122 max = mid - 1;
123 } else if (n > 0) {
124 min = mid + 1;
125 } else {
126 *out_hash = hash;
127 *out_index = mid;
128 return true;
129 }
130 }
131 }
132 }
133
134 return false;
135 }
136
GetInstance()137 static CommonCertSetsQUIC* GetInstance() {
138 return Singleton<CommonCertSetsQUIC>::get();
139 }
140
141 private:
CommonCertSetsQUIC()142 CommonCertSetsQUIC() {}
~CommonCertSetsQUIC()143 virtual ~CommonCertSetsQUIC() {}
144
145 friend struct DefaultSingletonTraits<CommonCertSetsQUIC>;
146 DISALLOW_COPY_AND_ASSIGN(CommonCertSetsQUIC);
147 };
148
149 } // anonymous namespace
150
~CommonCertSets()151 CommonCertSets::~CommonCertSets() {}
152
153 // static
GetInstanceQUIC()154 const CommonCertSets* CommonCertSets::GetInstanceQUIC() {
155 return CommonCertSetsQUIC::GetInstance();
156 }
157
158 } // namespace net
159