net/base/address_tracker_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_BASE_ADDRESS_TRACKER_LINUX_H_
   6 #define NET_BASE_ADDRESS_TRACKER_LINUX_H_
   7
   8 #include <sys/socket.h>  // Needed to include netlink.
   9 // Mask superfluous definition of |struct net|. This is fixed in Linux 2.6.38.
  10 #define net net_kernel
  11 #include <linux/rtnetlink.h>
  12 #undef net
  13
  14 #include <map>
  15
  16 #include "base/basictypes.h"
  17 #include "base/callback.h"
  18 #include "base/compiler_specific.h"
  19 #include "base/containers/hash_tables.h"
  20 #include "base/message_loop/message_loop.h"
  21 #include "base/synchronization/condition_variable.h"
  22 #include "base/synchronization/lock.h"
  23 #include "net/base/net_util.h"
  24 #include "net/base/network_change_notifier.h"
  25
  26 namespace net {
  27 namespace internal {
  28
  29 // Keeps track of network interface addresses using rtnetlink. Used by
  30 // NetworkChangeNotifier to provide signals to registered IPAddressObservers.
  31 class NET_EXPORT_PRIVATE AddressTrackerLinux :
  32     public base::MessageLoopForIO::Watcher {
  33  public:
  34   typedef std::map<IPAddressNumber, struct ifaddrmsg> AddressMap;
  35
  36   // Will run |address_callback| when the AddressMap changes, |link_callback|
  37   // when the list of online links changes, and |tunnel_callback| when the list
  38   // of online tunnels changes.
  39   AddressTrackerLinux(const base::Closure& address_callback,
  40                       const base::Closure& link_callback,
  41                       const base::Closure& tunnel_callback);
  42   virtual ~AddressTrackerLinux();
  43
  44   // Starts watching system configuration for changes. The current thread must
  45   // have a MessageLoopForIO.
  46   void Init();
  47
  48   AddressMap GetAddressMap() const;
  49
  50   // Implementation of NetworkChangeNotifierLinux::GetCurrentConnectionType().
  51   // Safe to call from any thread, but will block until Init() has completed.
  52   NetworkChangeNotifier::ConnectionType GetCurrentConnectionType();
  53
  54  private:
  55   friend class AddressTrackerLinuxTest;
  56
  57   // A function that returns the name of an interface given the interface index
  58   // in |interface_index|.
  59   typedef const char* (*GetInterfaceNameFunction)(int interface_index);
  60
  61   // Sets |*address_changed| to indicate whether |address_map_| changed and
  62   // sets |*link_changed| to indicate if |online_links_| changed and sets
  63   // |*tunnel_changed| to indicate if |online_links_| changed with regards to a
  64   // tunnel interface while reading messages from |netlink_fd_|.
  65   void ReadMessages(bool* address_changed,
  66                     bool* link_changed,
  67                     bool* tunnel_changed);
  68
  69   // Sets |*address_changed| to true if |address_map_| changed, sets
  70   // |*link_changed| to true if |online_links_| changed, sets |*tunnel_changed|
  71   // to true if |online_links_| changed with regards to a tunnel interface while
  72   // reading the message from |buffer|.
  73   void HandleMessage(char* buffer,
  74                      size_t length,
  75                      bool* address_changed,
  76                      bool* link_changed,
  77                      bool* tunnel_changed);
  78
  79   // Call when some part of initialization failed; forces online and unblocks.
  80   void AbortAndForceOnline();
  81
  82   // MessageLoopForIO::Watcher:
  83   virtual void OnFileCanReadWithoutBlocking(int fd) OVERRIDE;
  84   virtual void OnFileCanWriteWithoutBlocking(int /* fd */) OVERRIDE;
  85
  86   // Close |netlink_fd_|
  87   void CloseSocket();
  88
  89   // Does |msg| refer to a tunnel interface?
  90   bool IsTunnelInterface(const struct ifinfomsg* msg) const;
  91
  92   // Gets the name of an interface given the interface index |interface_index|.
  93   // May return empty string if it fails but should not return NULL. This is
  94   // overridden by tests.
  95   GetInterfaceNameFunction get_interface_name_;
  96
  97   base::Closure address_callback_;
  98   base::Closure link_callback_;
  99   base::Closure tunnel_callback_;
 100
 101   int netlink_fd_;
 102   base::MessageLoopForIO::FileDescriptorWatcher watcher_;
 103
 104   mutable base::Lock address_map_lock_;
 105   AddressMap address_map_;
 106
 107   // Set of interface indices for links that are currently online.
 108   base::hash_set<int> online_links_;
 109
 110   base::Lock is_offline_lock_;
 111   bool is_offline_;
 112   bool is_offline_initialized_;
 113   base::ConditionVariable is_offline_initialized_cv_;
 114 };
 115
 116 }  // namespace internal
 117 }  // namespace net
 118
 119 #endif  // NET_BASE_ADDRESS_TRACKER_LINUX_H_