sandbox/mac/mach_message_server.h

   1 // Copyright 2014 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 SANDBOX_MAC_MACH_MESSAGE_SERVER_H_
   6 #define SANDBOX_MAC_MACH_MESSAGE_SERVER_H_
   7
   8 #include <mach/mach.h>
   9
  10 #include "base/mac/scoped_mach_port.h"
  11 #include "base/mac/scoped_mach_vm.h"
  12 #include "base/memory/scoped_ptr.h"
  13 #include "sandbox/mac/message_server.h"
  14
  15 namespace sandbox {
  16
  17 class DispatchSourceMach;
  18
  19 // A Mach message server that operates a receive port. Messages are received
  20 // and then passed to the MessageDemuxer for handling. The Demuxer
  21 // can use the server class to send a reply, forward the message to a
  22 // different port, or reply to the message with a MIG error.
  23 class MachMessageServer : public MessageServer {
  24  public:
  25   // Creates a new Mach message server that will send messages to |demuxer|
  26   // for handling. If the |server_receive_right| is non-NULL, this class will
  27   // take ownership of the port and it will be used to receive messages.
  28   // Otherwise the server will create a new receive right.
  29   // The maximum size of messages is specified by |buffer_size|.
  30   MachMessageServer(MessageDemuxer* demuxer,
  31                     mach_port_t server_receive_right,
  32                     mach_msg_size_t buffer_size);
  33   ~MachMessageServer() override;
  34
  35   // MessageServer:
  36   bool Initialize() override;
  37   pid_t GetMessageSenderPID(IPCMessage request) override;
  38   IPCMessage CreateReply(IPCMessage request) override;
  39   bool SendReply(IPCMessage reply) override;
  40   void ForwardMessage(IPCMessage request, mach_port_t destination) override;
  41   // Replies to the message with the specified |error_code| as a MIG
  42   // error_reply RetCode.
  43   void RejectMessage(IPCMessage request, int error_code) override;
  44   mach_port_t GetServerPort() const override;
  45
  46  private:
  47   // Event handler for the |server_source_| that reads a message from the queue
  48   // and processes it.
  49   void ReceiveMessage();
  50
  51   // The demuxer delegate. Weak.
  52   MessageDemuxer* demuxer_;
  53
  54   // The Mach port on which the server is receiving requests.
  55   base::mac::ScopedMachReceiveRight server_port_;
  56
  57   // The size of the two message buffers below.
  58   const mach_msg_size_t buffer_size_;
  59
  60   // Request and reply buffers used in ReceiveMessage.
  61   base::mac::ScopedMachVM request_buffer_;
  62   base::mac::ScopedMachVM reply_buffer_;
  63
  64   // MACH_RECV dispatch source that handles the |server_port_|.
  65   scoped_ptr<DispatchSourceMach> dispatch_source_;
  66
  67   // Whether or not ForwardMessage() was called during ReceiveMessage().
  68   bool did_forward_message_;
  69 };
  70
  71 }  // namespace sandbox
  72
  73 #endif  // SANDBOX_MAC_MACH_MESSAGE_SERVER_H_