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