ipc/mojo/ipc_mojo_bootstrap.cc

   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 #include "ipc/mojo/ipc_mojo_bootstrap.h"
   6
   7 #include "base/logging.h"
   8 #include "base/process/process_handle.h"
   9 #include "ipc/ipc_message_utils.h"
  10 #include "ipc/ipc_platform_file.h"
  11 #include "mojo/edk/embedder/platform_channel_pair.h"
  12
  13 namespace IPC {
  14
  15 namespace {
  16
  17 // MojoBootstrap for the server process. You should create the instance
  18 // using MojoBootstrap::Create().
  19 class MojoServerBootstrap : public MojoBootstrap {
  20  public:
  21   MojoServerBootstrap();
  22
  23   void OnClientLaunched(base::ProcessHandle process) override;
  24
  25  private:
  26   void SendClientPipe();
  27   void SendClientPipeIfReady();
  28
  29   // Listener implementations
  30   bool OnMessageReceived(const Message& message) override;
  31   void OnChannelConnected(int32 peer_pid) override;
  32
  33   mojo::embedder::ScopedPlatformHandle server_pipe_;
  34   base::ProcessHandle client_process_;
  35   bool connected_;
  36
  37   DISALLOW_COPY_AND_ASSIGN(MojoServerBootstrap);
  38 };
  39
  40 MojoServerBootstrap::MojoServerBootstrap()
  41     : client_process_(base::kNullProcessHandle), connected_(false) {
  42 }
  43
  44 void MojoServerBootstrap::SendClientPipe() {
  45   DCHECK_EQ(state(), STATE_INITIALIZED);
  46   DCHECK_NE(client_process_, base::kNullProcessHandle);
  47   DCHECK(connected_);
  48
  49   mojo::embedder::PlatformChannelPair channel_pair;
  50   server_pipe_ = channel_pair.PassServerHandle();
  51   PlatformFileForTransit client_pipe = GetFileHandleForProcess(
  52 #if defined(OS_POSIX)
  53       channel_pair.PassClientHandle().release().fd,
  54 #else
  55       channel_pair.PassClientHandle().release().handle,
  56 #endif
  57       client_process_,
  58       true);
  59   if (client_pipe == IPC::InvalidPlatformFileForTransit()) {
  60 #if !defined(OS_WIN)
  61     // GetFileHandleForProcess() only fails on Windows.
  62     NOTREACHED();
  63 #endif
  64     DLOG(WARNING) << "Failed to translate file handle for client process.";
  65     Fail();
  66     return;
  67   }
  68
  69   scoped_ptr<Message> message(new Message());
  70   ParamTraits<PlatformFileForTransit>::Write(message.get(), client_pipe);
  71   Send(message.release());
  72
  73   set_state(STATE_WAITING_ACK);
  74 }
  75
  76 void MojoServerBootstrap::SendClientPipeIfReady() {
  77   // Is the client launched?
  78   if (client_process_ == base::kNullProcessHandle)
  79     return;
  80   // Has the bootstrap channel been made?
  81   if (!connected_)
  82     return;
  83   SendClientPipe();
  84 }
  85
  86 void MojoServerBootstrap::OnClientLaunched(base::ProcessHandle process) {
  87   if (HasFailed())
  88     return;
  89
  90   DCHECK_EQ(state(), STATE_INITIALIZED);
  91   DCHECK_NE(process, base::kNullProcessHandle);
  92   client_process_ = process;
  93   SendClientPipeIfReady();
  94 }
  95
  96 void MojoServerBootstrap::OnChannelConnected(int32 peer_pid) {
  97   DCHECK_EQ(state(), STATE_INITIALIZED);
  98   connected_ = true;
  99   SendClientPipeIfReady();
 100 }
 101
 102 bool MojoServerBootstrap::OnMessageReceived(const Message&) {
 103   if (state() != STATE_WAITING_ACK) {
 104     set_state(STATE_ERROR);
 105     LOG(ERROR) << "Got inconsistent message from client.";
 106     return false;
 107   }
 108
 109   set_state(STATE_READY);
 110   CHECK(server_pipe_.is_valid());
 111   delegate()->OnPipeAvailable(
 112       mojo::embedder::ScopedPlatformHandle(server_pipe_.release()));
 113
 114   return true;
 115 }
 116
 117 // MojoBootstrap for client processes. You should create the instance
 118 // using MojoBootstrap::Create().
 119 class MojoClientBootstrap : public MojoBootstrap {
 120  public:
 121   MojoClientBootstrap();
 122
 123   void OnClientLaunched(base::ProcessHandle process) override;
 124
 125  private:
 126   // Listener implementations
 127   bool OnMessageReceived(const Message& message) override;
 128   void OnChannelConnected(int32 peer_pid) override;
 129
 130   DISALLOW_COPY_AND_ASSIGN(MojoClientBootstrap);
 131 };
 132
 133 MojoClientBootstrap::MojoClientBootstrap() {
 134 }
 135
 136 bool MojoClientBootstrap::OnMessageReceived(const Message& message) {
 137   if (state() != STATE_INITIALIZED) {
 138     set_state(STATE_ERROR);
 139     LOG(ERROR) << "Got inconsistent message from server.";
 140     return false;
 141   }
 142
 143   PlatformFileForTransit pipe;
 144   PickleIterator iter(message);
 145   if (!ParamTraits<PlatformFileForTransit>::Read(&message, &iter, &pipe)) {
 146     DLOG(WARNING) << "Failed to read a file handle from bootstrap channel.";
 147     message.set_dispatch_error();
 148     return false;
 149   }
 150
 151   // Sends ACK back.
 152   Send(new Message());
 153   set_state(STATE_READY);
 154   delegate()->OnPipeAvailable(
 155       mojo::embedder::ScopedPlatformHandle(mojo::embedder::PlatformHandle(
 156           PlatformFileForTransitToPlatformFile(pipe))));
 157
 158   return true;
 159 }
 160
 161 void MojoClientBootstrap::OnClientLaunched(base::ProcessHandle process) {
 162   // This notification should happen only on server processes.
 163   NOTREACHED();
 164 }
 165
 166 void MojoClientBootstrap::OnChannelConnected(int32 peer_pid) {
 167 }
 168
 169 }  // namespace
 170
 171 // MojoBootstrap
 172
 173 // static
 174 scoped_ptr<MojoBootstrap> MojoBootstrap::Create(ChannelHandle handle,
 175                                                 Channel::Mode mode,
 176                                                 Delegate* delegate) {
 177   CHECK(mode == Channel::MODE_CLIENT || mode == Channel::MODE_SERVER);
 178   scoped_ptr<MojoBootstrap> self =
 179       mode == Channel::MODE_CLIENT
 180           ? scoped_ptr<MojoBootstrap>(new MojoClientBootstrap())
 181           : scoped_ptr<MojoBootstrap>(new MojoServerBootstrap());
 182   scoped_ptr<Channel> bootstrap_channel =
 183       Channel::Create(handle, mode, self.get());
 184   self->Init(bootstrap_channel.Pass(), delegate);
 185   return self.Pass();
 186 }
 187
 188 MojoBootstrap::MojoBootstrap() : delegate_(NULL), state_(STATE_INITIALIZED) {
 189 }
 190
 191 MojoBootstrap::~MojoBootstrap() {
 192 }
 193
 194 void MojoBootstrap::Init(scoped_ptr<Channel> channel, Delegate* delegate) {
 195   channel_ = channel.Pass();
 196   delegate_ = delegate;
 197 }
 198
 199 bool MojoBootstrap::Connect() {
 200   return channel_->Connect();
 201 }
 202
 203 void MojoBootstrap::OnBadMessageReceived(const Message& message) {
 204   Fail();
 205 }
 206
 207 void MojoBootstrap::OnChannelError() {
 208   if (state_ == STATE_READY || state_ == STATE_ERROR)
 209     return;
 210   DLOG(WARNING) << "Detected error on Mojo bootstrap channel.";
 211   Fail();
 212 }
 213
 214 void MojoBootstrap::Fail() {
 215   set_state(STATE_ERROR);
 216   delegate()->OnBootstrapError();
 217 }
 218
 219 bool MojoBootstrap::HasFailed() const {
 220   return state() == STATE_ERROR;
 221 }
 222
 223 bool MojoBootstrap::Send(Message* message) {
 224   return channel_->Send(message);
 225 }
 226
 227 #if defined(OS_POSIX) && !defined(OS_NACL)
 228 int MojoBootstrap::GetClientFileDescriptor() const {
 229   return channel_->GetClientFileDescriptor();
 230 }
 231
 232 base::ScopedFD MojoBootstrap::TakeClientFileDescriptor() {
 233   return channel_->TakeClientFileDescriptor();
 234 }
 235 #endif  // defined(OS_POSIX) && !defined(OS_NACL)
 236
 237 }  // namespace IPC