ipc/glue/NodeChannel.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
   5  * You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef mozilla_ipc_NodeChannel_h
   8 #define mozilla_ipc_NodeChannel_h
   9
  10 #include "mojo/core/ports/node.h"
  11 #include "mojo/core/ports/node_delegate.h"
  12 #include "base/process.h"
  13 #include "chrome/common/ipc_message.h"
  14 #include "chrome/common/ipc_channel.h"
  15 #include "mozilla/ipc/ProtocolUtils.h"
  16 #include "nsISupports.h"
  17 #include "nsTHashMap.h"
  18 #include "mozilla/Queue.h"
  19 #include "mozilla/DataMutex.h"
  20 #include "mozilla/UniquePtr.h"
  21
  22 #ifdef FUZZING_SNAPSHOT
  23 #  include "mozilla/fuzzing/IPCFuzzController.h"
  24 #endif
  25
  26 namespace mozilla::ipc {
  27
  28 class GeckoChildProcessHost;
  29 class NodeController;
  30
  31 // Represents a live connection between our Node and a remote process. This
  32 // object acts as an IPC::Channel listener and performs basic processing on
  33 // messages as they're passed between processes.
  34
  35 class NodeChannel final : public IPC::Channel::Listener {
  36   using NodeName = mojo::core::ports::NodeName;
  37   using PortName = mojo::core::ports::PortName;
  38
  39 #ifdef FUZZING_SNAPSHOT
  40   // Required because IPCFuzzController calls OnMessageReceived.
  41   friend class mozilla::fuzzing::IPCFuzzController;
  42 #endif
  43
  44  public:
  45   NS_INLINE_DECL_THREADSAFE_REFCOUNTING_WITH_DESTROY(NodeChannel, Destroy())
  46
  47   struct Introduction {
  48     NodeName mName;
  49     IPC::Channel::ChannelHandle mHandle;
  50     IPC::Channel::Mode mMode;
  51     base::ProcessId mMyPid = base::kInvalidProcessId;
  52     base::ProcessId mOtherPid = base::kInvalidProcessId;
  53   };
  54
  55   class Listener {
  56    public:
  57     virtual ~Listener() = default;
  58
  59     NS_INLINE_DECL_PURE_VIRTUAL_REFCOUNTING
  60
  61     virtual void OnEventMessage(const NodeName& aFromNode,
  62                                 UniquePtr<IPC::Message> aMessage) = 0;
  63     virtual void OnBroadcast(const NodeName& aFromNode,
  64                              UniquePtr<IPC::Message> aMessage) = 0;
  65     virtual void OnIntroduce(const NodeName& aFromNode,
  66                              Introduction aIntroduction) = 0;
  67     virtual void OnRequestIntroduction(const NodeName& aFromNode,
  68                                        const NodeName& aName) = 0;
  69     virtual void OnAcceptInvite(const NodeName& aFromNode,
  70                                 const NodeName& aRealName,
  71                                 const PortName& aInitialPort) = 0;
  72     virtual void OnChannelError(const NodeName& aFromNode) = 0;
  73   };
  74
  75   NodeChannel(const NodeName& aName, UniquePtr<IPC::Channel> aChannel,
  76               Listener* aListener,
  77               base::ProcessId aPid = base::kInvalidProcessId,
  78               GeckoChildProcessHost* aChildProcessHost = nullptr);
  79
  80   // Send the given message over this peer channel link. May be called from any
  81   // thread.
  82   void SendEventMessage(UniquePtr<IPC::Message> aMessage);
  83
  84   // Ask the broker process to broadcast this message to every node. May be
  85   // called from any thread.
  86   void Broadcast(UniquePtr<IPC::Message> aMessage);
  87
  88   // Ask the broker process to introduce this node to another node with the
  89   // given name. May be called from any thread.
  90   void RequestIntroduction(const NodeName& aPeerName);
  91
  92   // Send an introduction to the target node. May be called from any thread.
  93   void Introduce(Introduction aIntroduction);
  94
  95   void AcceptInvite(const NodeName& aRealName, const PortName& aInitialPort);
  96
  97   // The PID of the remote process, once known. May be called from any thread.
  98   base::ProcessId OtherPid() const { return mOtherPid; }
  99
 100   // Start communicating with the remote process using this NodeChannel. MUST BE
 101   // CALLED FROM THE IO THREAD.
 102   void Start();
 103
 104   // Stop communicating with the remote process using this NodeChannel, MUST BE
 105   // CALLED FROM THE IO THREAD.
 106   void Close();
 107
 108   // Only ever called by NodeController to update the name after an invite has
 109   // completed. MUST BE CALLED FROM THE IO THREAD.
 110   void SetName(const NodeName& aNewName) { mName = aNewName; }
 111
 112 #ifdef FUZZING_SNAPSHOT
 113   // MUST BE CALLED FROM THE IO THREAD.
 114   const NodeName& GetName() { return mName; }
 115 #endif
 116
 117   // Update the known PID for the remote process. MUST BE CALLED FROM THE IO
 118   // THREAD.
 119   void SetOtherPid(base::ProcessId aNewPid);
 120
 121 #ifdef XP_MACOSX
 122   // Called by the GeckoChildProcessHost to provide the task_t for the peer
 123   // process. MUST BE CALLED FROM THE IO THREAD.
 124   void SetMachTaskPort(task_t aTask);
 125 #endif
 126
 127  private:
 128   ~NodeChannel();
 129
 130   void Destroy();
 131   void FinalDestroy();
 132
 133   void SendMessage(UniquePtr<IPC::Message> aMessage);
 134
 135   // IPC::Channel::Listener implementation
 136   void OnMessageReceived(UniquePtr<IPC::Message> aMessage) override;
 137   void OnChannelConnected(base::ProcessId aPeerPid) override;
 138   void OnChannelError() override;
 139
 140   // NOTE: This strong reference will create a reference cycle between the
 141   // listener and the NodeChannel while it is in use. The Listener must clear
 142   // its reference to the NodeChannel to avoid leaks before shutdown.
 143   const RefPtr<Listener> mListener;
 144
 145   // The apparent name of this Node. This may change during the invite process
 146   // while waiting for the remote node name to be communicated to us.
 147
 148   // WARNING: This must only be accessed on the IO thread.
 149   NodeName mName;
 150
 151   // NOTE: This won't change once the connection has been established, but may
 152   // be `-1` until then. This will only be written to on the IO thread, but may
 153   // be read from other threads.
 154   std::atomic<base::ProcessId> mOtherPid;
 155
 156   // WARNING: Most methods on the IPC::Channel are only safe to call on the IO
 157   // thread, however it is safe to call `Send()` and `IsClosed()` from other
 158   // threads. See IPC::Channel's documentation for details.
 159   const mozilla::UniquePtr<IPC::Channel> mChannel;
 160
 161   // The state will start out as `State::Active`, and will only transition to
 162   // `State::Closed` on the IO thread. If a Send fails, the state will
 163   // transition to `State::Closing`, and a runnable will be dispatched to the
 164   // I/O thread to notify callbacks.
 165   enum class State { Active, Closing, Closed };
 166   std::atomic<State> mState = State::Active;
 167
 168 #ifdef FUZZING_SNAPSHOT
 169   std::atomic<bool> mBlockSendRecv = false;
 170 #endif
 171
 172   // WARNING: Must only be accessed on the IO thread.
 173   WeakPtr<mozilla::ipc::GeckoChildProcessHost> mChildProcessHost;
 174 };
 175
 176 }  // namespace mozilla::ipc
 177
 178 #endif