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