ipc/ipc_channel_win.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 IPC_IPC_CHANNEL_WIN_H_
   6 #define IPC_IPC_CHANNEL_WIN_H_
   7
   8 #include "ipc/ipc_channel.h"
   9
  10 #include <stdint.h>
  11
  12 #include <queue>
  13 #include <string>
  14
  15 #include "base/memory/scoped_ptr.h"
  16 #include "base/memory/weak_ptr.h"
  17 #include "base/message_loop/message_loop.h"
  18 #include "base/win/scoped_handle.h"
  19 #include "ipc/ipc_channel_reader.h"
  20
  21 namespace base {
  22 class ThreadChecker;
  23 }
  24
  25 namespace IPC {
  26
  27 class ChannelWin : public Channel,
  28                    public internal::ChannelReader,
  29                    public base::MessageLoopForIO::IOHandler {
  30  public:
  31   // Mirror methods of Channel, see ipc_channel.h for description.
  32   // |broker| must outlive the newly created object.
  33   ChannelWin(const IPC::ChannelHandle& channel_handle,
  34              Mode mode,
  35              Listener* listener);
  36   ~ChannelWin() override;
  37
  38   // Channel implementation
  39   bool Connect() override;
  40   void Close() override;
  41   bool Send(Message* message) override;
  42   AttachmentBroker* GetAttachmentBroker() override;
  43   base::ProcessId GetPeerPID() const override;
  44   base::ProcessId GetSelfPID() const override;
  45
  46   static bool IsNamedServerInitialized(const std::string& channel_id);
  47
  48
  49  private:
  50   // ChannelReader implementation.
  51   ReadState ReadData(char* buffer, int buffer_len, int* bytes_read) override;
  52   bool ShouldDispatchInputMessage(Message* msg) override;
  53   bool GetNonBrokeredAttachments(Message* msg) override;
  54   bool DidEmptyInputBuffers() override;
  55   void HandleInternalMessage(const Message& msg) override;
  56   base::ProcessId GetSenderPID() override;
  57   bool IsAttachmentBrokerEndpoint() override;
  58
  59   static const base::string16 PipeName(const std::string& channel_id,
  60                                        int32_t* secret);
  61   bool CreatePipe(const IPC::ChannelHandle &channel_handle, Mode mode);
  62
  63   bool ProcessConnection();
  64   bool ProcessOutgoingMessages(base::MessageLoopForIO::IOContext* context,
  65                                DWORD bytes_written);
  66
  67   // Returns |false| on channel error.
  68   // If |message| has brokerable attachments, those attachments are passed to
  69   // the AttachmentBroker (which in turn invokes Send()), so this method must
  70   // be re-entrant.
  71   // Adds |message| to |output_queue_| and calls ProcessOutgoingMessages().
  72   bool ProcessMessageForDelivery(Message* message);
  73
  74   // Moves all messages from |prelim_queue_| to |output_queue_| by calling
  75   // ProcessMessageForDelivery().
  76   void FlushPrelimQueue();
  77
  78   // MessageLoop::IOHandler implementation.
  79   void OnIOCompleted(base::MessageLoopForIO::IOContext* context,
  80                      DWORD bytes_transfered,
  81                      DWORD error) override;
  82
  83  private:
  84   struct State {
  85     explicit State(ChannelWin* channel);
  86     ~State();
  87     base::MessageLoopForIO::IOContext context;
  88     bool is_pending;
  89   };
  90
  91   State input_state_;
  92   State output_state_;
  93
  94   base::win::ScopedHandle pipe_;
  95
  96   base::ProcessId peer_pid_;
  97
  98   // Messages not yet ready to be sent are queued here. Messages removed from
  99   // this queue are placed in the output_queue_. The double queue is
 100   // unfortunate, but is necessary because messages with brokerable attachments
 101   // can generate multiple messages to be sent (possibly from other channels).
 102   // Some of these generated messages cannot be sent until |peer_pid_| has been
 103   // configured.
 104   // As soon as |peer_pid| has been configured, there is no longer any need for
 105   // |prelim_queue_|. All messages are flushed, and no new messages are added.
 106   std::queue<Message*> prelim_queue_;
 107
 108   // Messages to be sent are queued here.
 109   std::queue<OutputElement*> output_queue_;
 110
 111   // In server-mode, we have to wait for the client to connect before we
 112   // can begin reading.  We make use of the input_state_ when performing
 113   // the connect operation in overlapped mode.
 114   bool waiting_connect_;
 115
 116   // This flag is set when processing incoming messages.  It is used to
 117   // avoid recursing through ProcessIncomingMessages, which could cause
 118   // problems.  TODO(darin): make this unnecessary
 119   bool processing_incoming_;
 120
 121   // Determines if we should validate a client's secret on connection.
 122   bool validate_client_;
 123
 124   // Tracks the lifetime of this object, for debugging purposes.
 125   uint32_t debug_flags_;
 126
 127   // This is a unique per-channel value used to authenticate the client end of
 128   // a connection. If the value is non-zero, the client passes it in the hello
 129   // and the host validates. (We don't send the zero value fto preserve IPC
 130   // compatability with existing clients that don't validate the channel.)
 131   int32_t client_secret_;
 132
 133   scoped_ptr<base::ThreadChecker> thread_check_;
 134
 135   base::WeakPtrFactory<ChannelWin> weak_factory_;
 136   DISALLOW_COPY_AND_ASSIGN(ChannelWin);
 137 };
 138
 139 }  // namespace IPC
 140
 141 #endif  // IPC_IPC_CHANNEL_WIN_H_