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 #ifndef NET_DNS_DNS_CONFIG_SERVICE_H_ | |
6 #define NET_DNS_DNS_CONFIG_SERVICE_H_ | |
7 | |
8 #include <map> | |
9 #include <string> | |
10 #include <vector> | |
11 | |
12 #include "base/gtest_prod_util.h" | |
13 #include "base/memory/scoped_ptr.h" | |
14 #include "base/memory/scoped_vector.h" | |
15 #include "base/threading/non_thread_safe.h" | |
16 #include "base/time/time.h" | |
17 #include "base/timer/timer.h" | |
18 // Needed on shared build with MSVS2010 to avoid multiple definitions of | |
19 // std::vector<IPEndPoint>. | |
20 #include "net/base/address_list.h" | |
21 #include "net/base/ip_endpoint.h" // win requires size of IPEndPoint | |
22 #include "net/base/net_export.h" | |
23 #include "net/dns/dns_hosts.h" | |
24 | |
25 namespace base { | |
26 class Value; | |
27 } | |
28 | |
29 namespace net { | |
30 | |
31 // Always use 1 second timeout (followed by binary exponential backoff). | |
32 // TODO(szym): Remove code which reads timeout from system. | |
33 const unsigned kDnsTimeoutSeconds = 1; | |
34 | |
35 // Classifies nameserver address lists for histograms. | |
36 class NET_EXPORT_PRIVATE NameServerClassifier { | |
37 public: | |
38 // This is used in a histogram (AsyncDNS.NameServersType); add new entries | |
39 // right before MAX_VALUE. | |
40 enum NameServersType { | |
41 NAME_SERVERS_TYPE_NONE, | |
42 NAME_SERVERS_TYPE_GOOGLE_PUBLIC_DNS, | |
43 NAME_SERVERS_TYPE_PRIVATE, | |
44 NAME_SERVERS_TYPE_PUBLIC, | |
45 NAME_SERVERS_TYPE_MIXED, | |
46 NAME_SERVERS_TYPE_MAX_VALUE | |
47 }; | |
48 | |
49 NameServerClassifier(); | |
50 ~NameServerClassifier(); | |
51 | |
52 NameServersType GetNameServersType( | |
53 const std::vector<net::IPEndPoint>& nameservers) const; | |
54 | |
55 private: | |
56 struct NameServerTypeRule; | |
57 | |
58 void AddRule(const char* pattern_string, NameServersType type); | |
59 NameServersType GetNameServerType(const IPAddressNumber& address) const; | |
60 static NameServersType MergeNameServersTypes(NameServersType a, | |
61 NameServersType b); | |
62 | |
63 ScopedVector<NameServerTypeRule> rules_; | |
64 }; | |
65 | |
66 // DnsConfig stores configuration of the system resolver. | |
67 struct NET_EXPORT_PRIVATE DnsConfig { | |
68 DnsConfig(); | |
69 virtual ~DnsConfig(); | |
70 | |
71 bool Equals(const DnsConfig& d) const; | |
72 | |
73 bool EqualsIgnoreHosts(const DnsConfig& d) const; | |
74 | |
75 void CopyIgnoreHosts(const DnsConfig& src); | |
76 | |
77 // Returns a Value representation of |this|. Caller takes ownership of the | |
78 // returned Value. For performance reasons, the Value only contains the | |
79 // number of hosts rather than the full list. | |
80 base::Value* ToValue() const; | |
81 | |
82 bool IsValid() const { | |
83 return !nameservers.empty(); | |
84 } | |
85 | |
86 // List of name server addresses. | |
87 std::vector<IPEndPoint> nameservers; | |
88 // Suffix search list; used on first lookup when number of dots in given name | |
89 // is less than |ndots|. | |
90 std::vector<std::string> search; | |
91 | |
92 DnsHosts hosts; | |
93 | |
94 // True if there are options set in the system configuration that are not yet | |
95 // supported by DnsClient. | |
96 bool unhandled_options; | |
97 | |
98 // AppendToMultiLabelName: is suffix search performed for multi-label names? | |
99 // True, except on Windows where it can be configured. | |
100 bool append_to_multi_label_name; | |
101 | |
102 // Indicates that source port randomization is required. This uses additional | |
103 // resources on some platforms. | |
104 bool randomize_ports; | |
105 | |
106 // Resolver options; see man resolv.conf. | |
107 | |
108 // Minimum number of dots before global resolution precedes |search|. | |
109 int ndots; | |
110 // Time between retransmissions, see res_state.retrans. | |
111 base::TimeDelta timeout; | |
112 // Maximum number of attempts, see res_state.retry. | |
113 int attempts; | |
114 // Round robin entries in |nameservers| for subsequent requests. | |
115 bool rotate; | |
116 // Enable EDNS0 extensions. | |
117 bool edns0; | |
118 | |
119 // Indicates system configuration uses local IPv6 connectivity, e.g., | |
120 // DirectAccess. This is exposed for HostResolver to skip IPv6 probes, | |
121 // as it may cause them to return incorrect results. | |
122 bool use_local_ipv6; | |
123 }; | |
124 | |
125 // Service for reading system DNS settings, on demand or when signalled by | |
126 // internal watchers and NetworkChangeNotifier. | |
127 class NET_EXPORT_PRIVATE DnsConfigService | |
128 : NON_EXPORTED_BASE(public base::NonThreadSafe) { | |
129 public: | |
130 // Callback interface for the client, called on the same thread as | |
131 // ReadConfig() and WatchConfig(). | |
132 typedef base::Callback<void(const DnsConfig& config)> CallbackType; | |
133 | |
134 // Creates the platform-specific DnsConfigService. | |
135 static scoped_ptr<DnsConfigService> CreateSystemService(); | |
136 | |
137 DnsConfigService(); | |
138 virtual ~DnsConfigService(); | |
139 | |
140 // Attempts to read the configuration. Will run |callback| when succeeded. | |
141 // Can be called at most once. | |
142 void ReadConfig(const CallbackType& callback); | |
143 | |
144 // Registers systems watchers. Will attempt to read config after watch starts, | |
145 // but only if watchers started successfully. Will run |callback| iff config | |
146 // changes from last call or has to be withdrawn. Can be called at most once. | |
147 // Might require MessageLoopForIO. | |
148 void WatchConfig(const CallbackType& callback); | |
149 | |
150 protected: | |
151 enum WatchStatus { | |
152 DNS_CONFIG_WATCH_STARTED = 0, | |
153 DNS_CONFIG_WATCH_FAILED_TO_START_CONFIG, | |
154 DNS_CONFIG_WATCH_FAILED_TO_START_HOSTS, | |
155 DNS_CONFIG_WATCH_FAILED_CONFIG, | |
156 DNS_CONFIG_WATCH_FAILED_HOSTS, | |
157 DNS_CONFIG_WATCH_MAX, | |
158 }; | |
159 | |
160 // Immediately attempts to read the current configuration. | |
161 virtual void ReadNow() = 0; | |
162 // Registers system watchers. Returns true iff succeeds. | |
163 virtual bool StartWatching() = 0; | |
164 | |
165 // Called when the current config (except hosts) has changed. | |
166 void InvalidateConfig(); | |
167 // Called when the current hosts have changed. | |
168 void InvalidateHosts(); | |
169 | |
170 // Called with new config. |config|.hosts is ignored. | |
171 void OnConfigRead(const DnsConfig& config); | |
172 // Called with new hosts. Rest of the config is assumed unchanged. | |
173 void OnHostsRead(const DnsHosts& hosts); | |
174 | |
175 void set_watch_failed(bool value) { watch_failed_ = value; } | |
176 | |
177 private: | |
178 // The timer counts from the last Invalidate* until complete config is read. | |
179 void StartTimer(); | |
180 void OnTimeout(); | |
181 // Called when the config becomes complete. Stops the timer. | |
182 void OnCompleteConfig(); | |
183 | |
184 CallbackType callback_; | |
185 | |
186 DnsConfig dns_config_; | |
187 | |
188 // True if any of the necessary watchers failed. In that case, the service | |
189 // will communicate changes via OnTimeout, but will only send empty DnsConfig. | |
190 bool watch_failed_; | |
191 // True after On*Read, before Invalidate*. Tells if the config is complete. | |
192 bool have_config_; | |
193 bool have_hosts_; | |
194 // True if receiver needs to be updated when the config becomes complete. | |
195 bool need_update_; | |
196 // True if the last config sent was empty (instead of |dns_config_|). | |
197 // Set when |timer_| expires. | |
198 bool last_sent_empty_; | |
199 | |
200 // Initialized and updated on Invalidate* call. | |
201 base::TimeTicks last_invalidate_config_time_; | |
202 base::TimeTicks last_invalidate_hosts_time_; | |
203 // Initialized and updated when |timer_| expires. | |
204 base::TimeTicks last_sent_empty_time_; | |
205 | |
206 // Started in Invalidate*, cleared in On*Read. | |
207 base::OneShotTimer<DnsConfigService> timer_; | |
208 | |
209 NameServerClassifier classifier_; | |
210 | |
211 DISALLOW_COPY_AND_ASSIGN(DnsConfigService); | |
212 }; | |
213 | |
214 } // namespace net | |
215 | |
216 #endif // NET_DNS_DNS_CONFIG_SERVICE_H_ | |
OLD | NEW |