OLD | NEW |
| (Empty) |
1 // Copyright (c) 2012 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/dns/dns_config_service.h" | |
6 | |
7 #include "base/logging.h" | |
8 #include "base/metrics/histogram.h" | |
9 #include "base/values.h" | |
10 #include "net/base/ip_endpoint.h" | |
11 #include "net/base/ip_pattern.h" | |
12 | |
13 namespace net { | |
14 | |
15 NameServerClassifier::NameServerClassifier() { | |
16 // Google Public DNS addresses from: | |
17 // https://developers.google.com/speed/public-dns/docs/using | |
18 AddRule("8.8.8.8", NAME_SERVERS_TYPE_GOOGLE_PUBLIC_DNS); | |
19 AddRule("8.8.4.4", NAME_SERVERS_TYPE_GOOGLE_PUBLIC_DNS); | |
20 AddRule("2001:4860:4860:0:0:0:0:8888", NAME_SERVERS_TYPE_GOOGLE_PUBLIC_DNS), | |
21 AddRule("2001:4860:4860:0:0:0:0:8844", NAME_SERVERS_TYPE_GOOGLE_PUBLIC_DNS), | |
22 | |
23 // Count localhost as private, since we don't know what upstream it uses: | |
24 AddRule("127.*.*.*", NAME_SERVERS_TYPE_PRIVATE); | |
25 AddRule("0:0:0:0:0:0:0:1", NAME_SERVERS_TYPE_PRIVATE); | |
26 | |
27 // RFC 1918 private addresses: | |
28 AddRule("10.*.*.*", NAME_SERVERS_TYPE_PRIVATE); | |
29 AddRule("172.[16-31].*.*", NAME_SERVERS_TYPE_PRIVATE); | |
30 AddRule("192.168.*.*", NAME_SERVERS_TYPE_PRIVATE); | |
31 | |
32 // IPv4 link-local addresses: | |
33 AddRule("169.254.*.*", NAME_SERVERS_TYPE_PRIVATE); | |
34 | |
35 // IPv6 link-local addresses: | |
36 AddRule("fe80:*:*:*:*:*:*:*", NAME_SERVERS_TYPE_PRIVATE); | |
37 | |
38 // Anything else counts as public: | |
39 AddRule("*.*.*.*", NAME_SERVERS_TYPE_PUBLIC); | |
40 AddRule("*:*:*:*:*:*:*:*", NAME_SERVERS_TYPE_PUBLIC); | |
41 } | |
42 | |
43 NameServerClassifier::~NameServerClassifier() {} | |
44 | |
45 NameServerClassifier::NameServersType NameServerClassifier::GetNameServersType( | |
46 const std::vector<IPEndPoint>& nameservers) const { | |
47 NameServersType type = NAME_SERVERS_TYPE_NONE; | |
48 for (std::vector<IPEndPoint>::const_iterator it = nameservers.begin(); | |
49 it != nameservers.end(); | |
50 ++it) { | |
51 type = MergeNameServersTypes(type, GetNameServerType(it->address())); | |
52 } | |
53 return type; | |
54 } | |
55 | |
56 struct NameServerClassifier::NameServerTypeRule { | |
57 NameServerTypeRule(const char* pattern_string, NameServersType type) | |
58 : type(type) { | |
59 bool parsed = pattern.ParsePattern(pattern_string); | |
60 DCHECK(parsed); | |
61 } | |
62 | |
63 IPPattern pattern; | |
64 NameServersType type; | |
65 }; | |
66 | |
67 void NameServerClassifier::AddRule(const char* pattern_string, | |
68 NameServersType address_type) { | |
69 rules_.push_back(new NameServerTypeRule(pattern_string, address_type)); | |
70 } | |
71 | |
72 NameServerClassifier::NameServersType NameServerClassifier::GetNameServerType( | |
73 const IPAddressNumber& address) const { | |
74 for (ScopedVector<NameServerTypeRule>::const_iterator it = rules_.begin(); | |
75 it != rules_.end(); | |
76 ++it) { | |
77 if ((*it)->pattern.Match(address)) | |
78 return (*it)->type; | |
79 } | |
80 NOTREACHED(); | |
81 return NAME_SERVERS_TYPE_NONE; | |
82 } | |
83 | |
84 NameServerClassifier::NameServersType | |
85 NameServerClassifier::MergeNameServersTypes(NameServersType a, | |
86 NameServersType b) { | |
87 if (a == NAME_SERVERS_TYPE_NONE) | |
88 return b; | |
89 if (b == NAME_SERVERS_TYPE_NONE) | |
90 return a; | |
91 if (a == b) | |
92 return a; | |
93 return NAME_SERVERS_TYPE_MIXED; | |
94 } | |
95 | |
96 // Default values are taken from glibc resolv.h except timeout which is set to | |
97 // |kDnsTimeoutSeconds|. | |
98 DnsConfig::DnsConfig() | |
99 : unhandled_options(false), | |
100 append_to_multi_label_name(true), | |
101 randomize_ports(false), | |
102 ndots(1), | |
103 timeout(base::TimeDelta::FromSeconds(kDnsTimeoutSeconds)), | |
104 attempts(2), | |
105 rotate(false), | |
106 edns0(false), | |
107 use_local_ipv6(false) {} | |
108 | |
109 DnsConfig::~DnsConfig() {} | |
110 | |
111 bool DnsConfig::Equals(const DnsConfig& d) const { | |
112 return EqualsIgnoreHosts(d) && (hosts == d.hosts); | |
113 } | |
114 | |
115 bool DnsConfig::EqualsIgnoreHosts(const DnsConfig& d) const { | |
116 return (nameservers == d.nameservers) && | |
117 (search == d.search) && | |
118 (unhandled_options == d.unhandled_options) && | |
119 (append_to_multi_label_name == d.append_to_multi_label_name) && | |
120 (ndots == d.ndots) && | |
121 (timeout == d.timeout) && | |
122 (attempts == d.attempts) && | |
123 (rotate == d.rotate) && | |
124 (edns0 == d.edns0) && | |
125 (use_local_ipv6 == d.use_local_ipv6); | |
126 } | |
127 | |
128 void DnsConfig::CopyIgnoreHosts(const DnsConfig& d) { | |
129 nameservers = d.nameservers; | |
130 search = d.search; | |
131 unhandled_options = d.unhandled_options; | |
132 append_to_multi_label_name = d.append_to_multi_label_name; | |
133 ndots = d.ndots; | |
134 timeout = d.timeout; | |
135 attempts = d.attempts; | |
136 rotate = d.rotate; | |
137 edns0 = d.edns0; | |
138 use_local_ipv6 = d.use_local_ipv6; | |
139 } | |
140 | |
141 base::Value* DnsConfig::ToValue() const { | |
142 base::DictionaryValue* dict = new base::DictionaryValue(); | |
143 | |
144 base::ListValue* list = new base::ListValue(); | |
145 for (size_t i = 0; i < nameservers.size(); ++i) | |
146 list->Append(new base::StringValue(nameservers[i].ToString())); | |
147 dict->Set("nameservers", list); | |
148 | |
149 list = new base::ListValue(); | |
150 for (size_t i = 0; i < search.size(); ++i) | |
151 list->Append(new base::StringValue(search[i])); | |
152 dict->Set("search", list); | |
153 | |
154 dict->SetBoolean("unhandled_options", unhandled_options); | |
155 dict->SetBoolean("append_to_multi_label_name", append_to_multi_label_name); | |
156 dict->SetInteger("ndots", ndots); | |
157 dict->SetDouble("timeout", timeout.InSecondsF()); | |
158 dict->SetInteger("attempts", attempts); | |
159 dict->SetBoolean("rotate", rotate); | |
160 dict->SetBoolean("edns0", edns0); | |
161 dict->SetBoolean("use_local_ipv6", use_local_ipv6); | |
162 dict->SetInteger("num_hosts", hosts.size()); | |
163 | |
164 return dict; | |
165 } | |
166 | |
167 | |
168 DnsConfigService::DnsConfigService() | |
169 : watch_failed_(false), | |
170 have_config_(false), | |
171 have_hosts_(false), | |
172 need_update_(false), | |
173 last_sent_empty_(true) {} | |
174 | |
175 DnsConfigService::~DnsConfigService() { | |
176 } | |
177 | |
178 void DnsConfigService::ReadConfig(const CallbackType& callback) { | |
179 DCHECK(CalledOnValidThread()); | |
180 DCHECK(!callback.is_null()); | |
181 DCHECK(callback_.is_null()); | |
182 callback_ = callback; | |
183 ReadNow(); | |
184 } | |
185 | |
186 void DnsConfigService::WatchConfig(const CallbackType& callback) { | |
187 DCHECK(CalledOnValidThread()); | |
188 DCHECK(!callback.is_null()); | |
189 DCHECK(callback_.is_null()); | |
190 callback_ = callback; | |
191 watch_failed_ = !StartWatching(); | |
192 ReadNow(); | |
193 } | |
194 | |
195 void DnsConfigService::InvalidateConfig() { | |
196 DCHECK(CalledOnValidThread()); | |
197 base::TimeTicks now = base::TimeTicks::Now(); | |
198 if (!last_invalidate_config_time_.is_null()) { | |
199 UMA_HISTOGRAM_LONG_TIMES("AsyncDNS.ConfigNotifyInterval", | |
200 now - last_invalidate_config_time_); | |
201 } | |
202 last_invalidate_config_time_ = now; | |
203 if (!have_config_) | |
204 return; | |
205 have_config_ = false; | |
206 StartTimer(); | |
207 } | |
208 | |
209 void DnsConfigService::InvalidateHosts() { | |
210 DCHECK(CalledOnValidThread()); | |
211 base::TimeTicks now = base::TimeTicks::Now(); | |
212 if (!last_invalidate_hosts_time_.is_null()) { | |
213 UMA_HISTOGRAM_LONG_TIMES("AsyncDNS.HostsNotifyInterval", | |
214 now - last_invalidate_hosts_time_); | |
215 } | |
216 last_invalidate_hosts_time_ = now; | |
217 if (!have_hosts_) | |
218 return; | |
219 have_hosts_ = false; | |
220 StartTimer(); | |
221 } | |
222 | |
223 void DnsConfigService::OnConfigRead(const DnsConfig& config) { | |
224 DCHECK(CalledOnValidThread()); | |
225 DCHECK(config.IsValid()); | |
226 | |
227 bool changed = false; | |
228 if (!config.EqualsIgnoreHosts(dns_config_)) { | |
229 dns_config_.CopyIgnoreHosts(config); | |
230 need_update_ = true; | |
231 changed = true; | |
232 } | |
233 if (!changed && !last_sent_empty_time_.is_null()) { | |
234 UMA_HISTOGRAM_LONG_TIMES("AsyncDNS.UnchangedConfigInterval", | |
235 base::TimeTicks::Now() - last_sent_empty_time_); | |
236 } | |
237 UMA_HISTOGRAM_BOOLEAN("AsyncDNS.ConfigChange", changed); | |
238 UMA_HISTOGRAM_ENUMERATION( | |
239 "AsyncDNS.NameServersType", | |
240 classifier_.GetNameServersType(dns_config_.nameservers), | |
241 NameServerClassifier::NAME_SERVERS_TYPE_MAX_VALUE); | |
242 | |
243 have_config_ = true; | |
244 if (have_hosts_ || watch_failed_) | |
245 OnCompleteConfig(); | |
246 } | |
247 | |
248 void DnsConfigService::OnHostsRead(const DnsHosts& hosts) { | |
249 DCHECK(CalledOnValidThread()); | |
250 | |
251 bool changed = false; | |
252 if (hosts != dns_config_.hosts) { | |
253 dns_config_.hosts = hosts; | |
254 need_update_ = true; | |
255 changed = true; | |
256 } | |
257 if (!changed && !last_sent_empty_time_.is_null()) { | |
258 UMA_HISTOGRAM_LONG_TIMES("AsyncDNS.UnchangedHostsInterval", | |
259 base::TimeTicks::Now() - last_sent_empty_time_); | |
260 } | |
261 UMA_HISTOGRAM_BOOLEAN("AsyncDNS.HostsChange", changed); | |
262 | |
263 have_hosts_ = true; | |
264 if (have_config_ || watch_failed_) | |
265 OnCompleteConfig(); | |
266 } | |
267 | |
268 void DnsConfigService::StartTimer() { | |
269 DCHECK(CalledOnValidThread()); | |
270 if (last_sent_empty_) { | |
271 DCHECK(!timer_.IsRunning()); | |
272 return; // No need to withdraw again. | |
273 } | |
274 timer_.Stop(); | |
275 | |
276 // Give it a short timeout to come up with a valid config. Otherwise withdraw | |
277 // the config from the receiver. The goal is to avoid perceivable network | |
278 // outage (when using the wrong config) but at the same time avoid | |
279 // unnecessary Job aborts in HostResolverImpl. The signals come from multiple | |
280 // sources so it might receive multiple events during a config change. | |
281 | |
282 // DHCP and user-induced changes are on the order of seconds, so 150ms should | |
283 // not add perceivable delay. On the other hand, config readers should finish | |
284 // within 150ms with the rare exception of I/O block or extra large HOSTS. | |
285 const base::TimeDelta kTimeout = base::TimeDelta::FromMilliseconds(150); | |
286 | |
287 timer_.Start(FROM_HERE, | |
288 kTimeout, | |
289 this, | |
290 &DnsConfigService::OnTimeout); | |
291 } | |
292 | |
293 void DnsConfigService::OnTimeout() { | |
294 DCHECK(CalledOnValidThread()); | |
295 DCHECK(!last_sent_empty_); | |
296 // Indicate that even if there is no change in On*Read, we will need to | |
297 // update the receiver when the config becomes complete. | |
298 need_update_ = true; | |
299 // Empty config is considered invalid. | |
300 last_sent_empty_ = true; | |
301 last_sent_empty_time_ = base::TimeTicks::Now(); | |
302 callback_.Run(DnsConfig()); | |
303 } | |
304 | |
305 void DnsConfigService::OnCompleteConfig() { | |
306 timer_.Stop(); | |
307 if (!need_update_) | |
308 return; | |
309 need_update_ = false; | |
310 last_sent_empty_ = false; | |
311 if (watch_failed_) { | |
312 // If a watch failed, the config may not be accurate, so report empty. | |
313 callback_.Run(DnsConfig()); | |
314 } else { | |
315 callback_.Run(dns_config_); | |
316 } | |
317 } | |
318 | |
319 } // namespace net | |
320 | |
OLD | NEW |