net/proxy/proxy_config_service_linux.h

   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_PROXY_PROXY_CONFIG_SERVICE_LINUX_H_
   6 #define NET_PROXY_PROXY_CONFIG_SERVICE_LINUX_H_
   7
   8 #include <string>
   9 #include <vector>
  10
  11 #include "base/basictypes.h"
  12 #include "base/compiler_specific.h"
  13 #include "base/environment.h"
  14 #include "base/memory/ref_counted.h"
  15 #include "base/memory/scoped_ptr.h"
  16 #include "base/observer_list.h"
  17 #include "net/base/net_export.h"
  18 #include "net/proxy/proxy_config.h"
  19 #include "net/proxy/proxy_config_service.h"
  20 #include "net/proxy/proxy_server.h"
  21
  22 namespace base {
  23 class SingleThreadTaskRunner;
  24 }  // namespace base
  25
  26 namespace net {
  27
  28 // Implementation of ProxyConfigService that retrieves the system proxy
  29 // settings from environment variables, gconf, gsettings, or kioslaverc (KDE).
  30 class NET_EXPORT_PRIVATE ProxyConfigServiceLinux : public ProxyConfigService {
  31  public:
  32
  33   // Forward declaration of Delegate.
  34   class Delegate;
  35
  36   class SettingGetter {
  37    public:
  38     // Buffer size used in some implementations of this class when reading
  39     // files. Defined here so unit tests can construct worst-case inputs.
  40     static const size_t BUFFER_SIZE = 512;
  41
  42     SettingGetter() {}
  43     virtual ~SettingGetter() {}
  44
  45     // Initializes the class: obtains a gconf/gsettings client, or simulates
  46     // one, in the concrete implementations. Returns true on success. Must be
  47     // called before using other methods, and should be called on the thread
  48     // running the glib main loop.
  49     // One of |glib_task_runner| and |file_task_runner| will be
  50     // used for gconf/gsettings calls or reading necessary files, depending on
  51     // the implementation.
  52     virtual bool Init(
  53         const scoped_refptr<base::SingleThreadTaskRunner>& glib_task_runner,
  54         const scoped_refptr<base::SingleThreadTaskRunner>&
  55             file_task_runner) = 0;
  56
  57     // Releases the gconf/gsettings client, which clears cached directories and
  58     // stops notifications.
  59     virtual void ShutDown() = 0;
  60
  61     // Requests notification of gconf/gsettings changes for proxy
  62     // settings. Returns true on success.
  63     virtual bool SetUpNotifications(Delegate* delegate) = 0;
  64
  65     // Returns the message loop for the thread on which this object
  66     // handles notifications, and also on which it must be destroyed.
  67     // Returns NULL if it does not matter.
  68     virtual const scoped_refptr<base::SingleThreadTaskRunner>&
  69         GetNotificationTaskRunner() = 0;
  70
  71     // Returns the source of proxy settings.
  72     virtual ProxyConfigSource GetConfigSource() = 0;
  73
  74     // These are all the values that can be fetched. We used to just use the
  75     // corresponding paths in gconf for these, but gconf is now obsolete and
  76     // in the future we'll be using mostly gsettings/kioslaverc so we
  77     // enumerate them instead to avoid unnecessary string operations.
  78     enum StringSetting {
  79       PROXY_MODE,
  80       PROXY_AUTOCONF_URL,
  81       PROXY_HTTP_HOST,
  82       PROXY_HTTPS_HOST,
  83       PROXY_FTP_HOST,
  84       PROXY_SOCKS_HOST,
  85     };
  86     enum BoolSetting {
  87       PROXY_USE_HTTP_PROXY,
  88       PROXY_USE_SAME_PROXY,
  89       PROXY_USE_AUTHENTICATION,
  90     };
  91     enum IntSetting {
  92       PROXY_HTTP_PORT,
  93       PROXY_HTTPS_PORT,
  94       PROXY_FTP_PORT,
  95       PROXY_SOCKS_PORT,
  96     };
  97     enum StringListSetting {
  98       PROXY_IGNORE_HOSTS,
  99     };
 100
 101     // Given a PROXY_*_HOST value, return the corresponding PROXY_*_PORT value.
 102     static IntSetting HostSettingToPortSetting(StringSetting host) {
 103       switch (host) {
 104         case PROXY_HTTP_HOST:
 105           return PROXY_HTTP_PORT;
 106         case PROXY_HTTPS_HOST:
 107           return PROXY_HTTPS_PORT;
 108         case PROXY_FTP_HOST:
 109           return PROXY_FTP_PORT;
 110         case PROXY_SOCKS_HOST:
 111           return PROXY_SOCKS_PORT;
 112         default:
 113           NOTREACHED();
 114           return PROXY_HTTP_PORT;  // Placate compiler.
 115       }
 116     }
 117
 118     // Gets a string type value from the data source and stores it in
 119     // |*result|. Returns false if the key is unset or on error. Must only be
 120     // called after a successful call to Init(), and not after a failed call
 121     // to SetUpNotifications() or after calling Release().
 122     virtual bool GetString(StringSetting key, std::string* result) = 0;
 123     // Same thing for a bool typed value.
 124     virtual bool GetBool(BoolSetting key, bool* result) = 0;
 125     // Same for an int typed value.
 126     virtual bool GetInt(IntSetting key, int* result) = 0;
 127     // And for a string list.
 128     virtual bool GetStringList(StringListSetting key,
 129                                std::vector<std::string>* result) = 0;
 130
 131     // Returns true if the bypass list should be interpreted as a proxy
 132     // whitelist rather than blacklist. (This is KDE-specific.)
 133     virtual bool BypassListIsReversed() = 0;
 134
 135     // Returns true if the bypass rules should be interpreted as
 136     // suffix-matching rules.
 137     virtual bool MatchHostsUsingSuffixMatching() = 0;
 138
 139    private:
 140     DISALLOW_COPY_AND_ASSIGN(SettingGetter);
 141   };
 142
 143   // ProxyConfigServiceLinux is created on the UI thread, and
 144   // SetUpAndFetchInitialConfig() is immediately called to synchronously
 145   // fetch the original configuration and set up change notifications on
 146   // the UI thread.
 147   //
 148   // Past that point, it is accessed periodically through the
 149   // ProxyConfigService interface (GetLatestProxyConfig, AddObserver,
 150   // RemoveObserver) from the IO thread.
 151   //
 152   // Setting change notification callbacks can occur at any time and are
 153   // run on either the UI thread (gconf/gsettings) or the file thread
 154   // (KDE). The new settings are fetched on that thread, and the resulting
 155   // proxy config is posted to the IO thread through
 156   // Delegate::SetNewProxyConfig(). We then notify observers on the IO
 157   // thread of the configuration change.
 158   //
 159   // ProxyConfigServiceLinux is deleted from the IO thread.
 160   //
 161   // The substance of the ProxyConfigServiceLinux implementation is
 162   // wrapped in the Delegate ref counted class. On deleting the
 163   // ProxyConfigServiceLinux, Delegate::OnDestroy() is posted to either
 164   // the UI thread (gconf/gsettings) or the file thread (KDE) where change
 165   // notifications will be safely stopped before releasing Delegate.
 166
 167   class Delegate : public base::RefCountedThreadSafe<Delegate> {
 168    public:
 169     // Constructor receives env var getter implementation to use, and
 170     // takes ownership of it. This is the normal constructor.
 171     explicit Delegate(base::Environment* env_var_getter);
 172     // Constructor receives setting and env var getter implementations
 173     // to use, and takes ownership of them. Used for testing.
 174     Delegate(base::Environment* env_var_getter, SettingGetter* setting_getter);
 175
 176     // Synchronously obtains the proxy configuration. If gconf,
 177     // gsettings, or kioslaverc are used, also enables notifications for
 178     // setting changes. gconf/gsettings must only be accessed from the
 179     // thread running the default glib main loop, and so this method
 180     // must be called from the UI thread. The message loop for the IO
 181     // thread is specified so that notifications can post tasks to it
 182     // (and for assertions). The message loop for the file thread is
 183     // used to read any files needed to determine proxy settings.
 184     void SetUpAndFetchInitialConfig(
 185         const scoped_refptr<base::SingleThreadTaskRunner>& glib_task_runner,
 186         const scoped_refptr<base::SingleThreadTaskRunner>& io_task_runner,
 187         const scoped_refptr<base::SingleThreadTaskRunner>& file_task_runner);
 188
 189     // Handler for setting change notifications: fetches a new proxy
 190     // configuration from settings, and if this config is different
 191     // than what we had before, posts a task to have it stored in
 192     // cached_config_.
 193     // Left public for simplicity.
 194     void OnCheckProxyConfigSettings();
 195
 196     // Called from IO thread.
 197     void AddObserver(Observer* observer);
 198     void RemoveObserver(Observer* observer);
 199     ProxyConfigService::ConfigAvailability GetLatestProxyConfig(
 200         ProxyConfig* config);
 201
 202     // Posts a call to OnDestroy() to the UI or FILE thread, depending on the
 203     // setting getter in use. Called from ProxyConfigServiceLinux's destructor.
 204     void PostDestroyTask();
 205     // Safely stops change notifications. Posted to either the UI or FILE
 206     // thread, depending on the setting getter in use.
 207     void OnDestroy();
 208
 209    private:
 210     friend class base::RefCountedThreadSafe<Delegate>;
 211
 212     ~Delegate();
 213
 214     // Obtains an environment variable's value. Parses a proxy server
 215     // specification from it and puts it in result. Returns true if the
 216     // requested variable is defined and the value valid.
 217     bool GetProxyFromEnvVarForScheme(const char* variable,
 218                                      ProxyServer::Scheme scheme,
 219                                      ProxyServer* result_server);
 220     // As above but with scheme set to HTTP, for convenience.
 221     bool GetProxyFromEnvVar(const char* variable, ProxyServer* result_server);
 222     // Fills proxy config from environment variables. Returns true if
 223     // variables were found and the configuration is valid.
 224     bool GetConfigFromEnv(ProxyConfig* config);
 225
 226     // Obtains host and port config settings and parses a proxy server
 227     // specification from it and puts it in result. Returns true if the
 228     // requested variable is defined and the value valid.
 229     bool GetProxyFromSettings(SettingGetter::StringSetting host_key,
 230                               ProxyServer* result_server);
 231     // Fills proxy config from settings. Returns true if settings were found
 232     // and the configuration is valid.
 233     bool GetConfigFromSettings(ProxyConfig* config);
 234
 235     // This method is posted from the UI thread to the IO thread to
 236     // carry the new config information.
 237     void SetNewProxyConfig(const ProxyConfig& new_config);
 238
 239     // This method is run on the getter's notification thread.
 240     void SetUpNotifications();
 241
 242     scoped_ptr<base::Environment> env_var_getter_;
 243     scoped_ptr<SettingGetter> setting_getter_;
 244
 245     // Cached proxy configuration, to be returned by
 246     // GetLatestProxyConfig. Initially populated from the UI thread, but
 247     // afterwards only accessed from the IO thread.
 248     ProxyConfig cached_config_;
 249
 250     // A copy kept on the UI thread of the last seen proxy config, so as
 251     // to avoid posting a call to SetNewProxyConfig when we get a
 252     // notification but the config has not actually changed.
 253     ProxyConfig reference_config_;
 254
 255     // The task runner for the glib thread, aka main browser thread. This thread
 256     // is where we run the glib main loop (see
 257     // base/message_loop/message_pump_glib.h). It is the glib default loop in
 258     // the sense that it runs the glib default context: as in the context where
 259     // sources are added by g_timeout_add and g_idle_add, and returned by
 260     // g_main_context_default. gconf uses glib timeouts and idles and possibly
 261     // other callbacks that will all be dispatched on this thread. Since gconf
 262     // is not thread safe, any use of gconf must be done on the thread running
 263     // this loop.
 264     scoped_refptr<base::SingleThreadTaskRunner> glib_task_runner_;
 265     // Task runner for the IO thread. GetLatestProxyConfig() is called from
 266     // the thread running this loop.
 267     scoped_refptr<base::SingleThreadTaskRunner> io_task_runner_;
 268
 269     ObserverList<Observer> observers_;
 270
 271     DISALLOW_COPY_AND_ASSIGN(Delegate);
 272   };
 273
 274   // Thin wrapper shell around Delegate.
 275
 276   // Usual constructor
 277   ProxyConfigServiceLinux();
 278   // For testing: take alternate setting and env var getter implementations.
 279   explicit ProxyConfigServiceLinux(base::Environment* env_var_getter);
 280   ProxyConfigServiceLinux(base::Environment* env_var_getter,
 281                           SettingGetter* setting_getter);
 282
 283   virtual ~ProxyConfigServiceLinux();
 284
 285   void SetupAndFetchInitialConfig(
 286       const scoped_refptr<base::SingleThreadTaskRunner>& glib_task_runner,
 287       const scoped_refptr<base::SingleThreadTaskRunner>& io_task_runner,
 288       const scoped_refptr<base::SingleThreadTaskRunner>& file_task_runner) {
 289     delegate_->SetUpAndFetchInitialConfig(glib_task_runner,
 290                                           io_task_runner,
 291                                           file_task_runner);
 292   }
 293   void OnCheckProxyConfigSettings() {
 294     delegate_->OnCheckProxyConfigSettings();
 295   }
 296
 297   // ProxyConfigService methods:
 298   // Called from IO thread.
 299   virtual void AddObserver(Observer* observer) OVERRIDE;
 300   virtual void RemoveObserver(Observer* observer) OVERRIDE;
 301   virtual ProxyConfigService::ConfigAvailability GetLatestProxyConfig(
 302       ProxyConfig* config) OVERRIDE;
 303
 304  private:
 305   scoped_refptr<Delegate> delegate_;
 306
 307   DISALLOW_COPY_AND_ASSIGN(ProxyConfigServiceLinux);
 308 };
 309
 310 }  // namespace net
 311
 312 #endif  // NET_PROXY_PROXY_CONFIG_SERVICE_LINUX_H_