ipc/ipc_send_fds_test.cc

   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 #include "build/build_config.h"
   6
   7 #if defined(OS_POSIX)
   8 #if defined(OS_MACOSX)
   9 extern "C" {
  10 #include <sandbox.h>
  11 }
  12 #endif
  13 #include <fcntl.h>
  14 #include <sys/socket.h>
  15 #include <sys/stat.h>
  16 #include <unistd.h>
  17
  18 #include <queue>
  19
  20 #include "base/callback.h"
  21 #include "base/file_descriptor_posix.h"
  22 #include "base/message_loop/message_loop.h"
  23 #include "base/pickle.h"
  24 #include "base/posix/eintr_wrapper.h"
  25 #include "base/synchronization/waitable_event.h"
  26 #include "ipc/ipc_message_utils.h"
  27 #include "ipc/ipc_test_base.h"
  28
  29 namespace {
  30
  31 const unsigned kNumFDsToSend = 20;
  32 const char* kDevZeroPath = "/dev/zero";
  33
  34 class MyChannelDescriptorListenerBase : public IPC::Listener {
  35  public:
  36   virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE {
  37     PickleIterator iter(message);
  38
  39     base::FileDescriptor descriptor;
  40
  41     IPC::ParamTraits<base::FileDescriptor>::Read(&message, &iter, &descriptor);
  42
  43     HandleFD(descriptor.fd);
  44     return true;
  45   }
  46
  47  protected:
  48   virtual void HandleFD(int fd) = 0;
  49 };
  50
  51 class MyChannelDescriptorListener : public MyChannelDescriptorListenerBase {
  52  public:
  53   explicit MyChannelDescriptorListener(ino_t expected_inode_num)
  54       : MyChannelDescriptorListenerBase(),
  55         expected_inode_num_(expected_inode_num),
  56         num_fds_received_(0) {
  57   }
  58
  59   bool GotExpectedNumberOfDescriptors() const {
  60     return num_fds_received_ == kNumFDsToSend;
  61   }
  62
  63   virtual void OnChannelError() OVERRIDE {
  64     base::MessageLoop::current()->Quit();
  65   }
  66
  67  protected:
  68   virtual void HandleFD(int fd) OVERRIDE {
  69     // Check that we can read from the FD.
  70     char buf;
  71     ssize_t amt_read = read(fd, &buf, 1);
  72     ASSERT_EQ(amt_read, 1);
  73     ASSERT_EQ(buf, 0);  // /dev/zero always reads 0 bytes.
  74
  75     struct stat st;
  76     ASSERT_EQ(fstat(fd, &st), 0);
  77
  78     ASSERT_EQ(close(fd), 0);
  79
  80     // Compare inode numbers to check that the file sent over the wire is
  81     // actually the one expected.
  82     ASSERT_EQ(expected_inode_num_, st.st_ino);
  83
  84     ++num_fds_received_;
  85     if (num_fds_received_ == kNumFDsToSend)
  86       base::MessageLoop::current()->Quit();
  87   }
  88
  89  private:
  90   ino_t expected_inode_num_;
  91   unsigned num_fds_received_;
  92 };
  93
  94
  95 class IPCSendFdsTest : public IPCTestBase {
  96  protected:
  97   void RunServer() {
  98     // Set up IPC channel and start client.
  99     MyChannelDescriptorListener listener(-1);
 100     CreateChannel(&listener);
 101     ASSERT_TRUE(ConnectChannel());
 102     ASSERT_TRUE(StartClient());
 103
 104     for (unsigned i = 0; i < kNumFDsToSend; ++i) {
 105       const int fd = open(kDevZeroPath, O_RDONLY);
 106       ASSERT_GE(fd, 0);
 107       base::FileDescriptor descriptor(fd, true);
 108
 109       IPC::Message* message =
 110           new IPC::Message(0, 3, IPC::Message::PRIORITY_NORMAL);
 111       IPC::ParamTraits<base::FileDescriptor>::Write(message, descriptor);
 112       ASSERT_TRUE(sender()->Send(message));
 113     }
 114
 115     // Run message loop.
 116     base::MessageLoop::current()->Run();
 117
 118     // Close the channel so the client's OnChannelError() gets fired.
 119     channel()->Close();
 120
 121     EXPECT_TRUE(WaitForClientShutdown());
 122     DestroyChannel();
 123   }
 124 };
 125
 126 TEST_F(IPCSendFdsTest, DescriptorTest) {
 127   Init("SendFdsClient");
 128   RunServer();
 129 }
 130
 131 int SendFdsClientCommon(const std::string& test_client_name,
 132                         ino_t expected_inode_num) {
 133   base::MessageLoopForIO main_message_loop;
 134   MyChannelDescriptorListener listener(expected_inode_num);
 135
 136   // Set up IPC channel.
 137   scoped_ptr<IPC::Channel> channel(IPC::Channel::CreateClient(
 138       IPCTestBase::GetChannelName(test_client_name),
 139       &listener));
 140   CHECK(channel->Connect());
 141
 142   // Run message loop.
 143   base::MessageLoop::current()->Run();
 144
 145   // Verify that the message loop was exited due to getting the correct number
 146   // of descriptors, and not because of the channel closing unexpectedly.
 147   CHECK(listener.GotExpectedNumberOfDescriptors());
 148
 149   return 0;
 150 }
 151
 152 MULTIPROCESS_IPC_TEST_CLIENT_MAIN(SendFdsClient) {
 153   struct stat st;
 154   int fd = open(kDevZeroPath, O_RDONLY);
 155   fstat(fd, &st);
 156   EXPECT_GE(IGNORE_EINTR(close(fd)), 0);
 157   return SendFdsClientCommon("SendFdsClient", st.st_ino);
 158 }
 159
 160 #if defined(OS_MACOSX)
 161 // Test that FDs are correctly sent to a sandboxed process.
 162 // TODO(port): Make this test cross-platform.
 163 TEST_F(IPCSendFdsTest, DescriptorTestSandboxed) {
 164   Init("SendFdsSandboxedClient");
 165   RunServer();
 166 }
 167
 168 MULTIPROCESS_IPC_TEST_CLIENT_MAIN(SendFdsSandboxedClient) {
 169   struct stat st;
 170   const int fd = open(kDevZeroPath, O_RDONLY);
 171   fstat(fd, &st);
 172   if (IGNORE_EINTR(close(fd)) < 0)
 173     return -1;
 174
 175   // Enable the sandbox.
 176   char* error_buff = NULL;
 177   int error = sandbox_init(kSBXProfilePureComputation, SANDBOX_NAMED,
 178                            &error_buff);
 179   bool success = (error == 0 && error_buff == NULL);
 180   if (!success)
 181     return -1;
 182
 183   sandbox_free_error(error_buff);
 184
 185   // Make sure sandbox is really enabled.
 186   if (open(kDevZeroPath, O_RDONLY) != -1) {
 187     LOG(ERROR) << "Sandbox wasn't properly enabled";
 188     return -1;
 189   }
 190
 191   // See if we can receive a file descriptor.
 192   return SendFdsClientCommon("SendFdsSandboxedClient", st.st_ino);
 193 }
 194 #endif  // defined(OS_MACOSX)
 195
 196
 197 class MyCBListener : public MyChannelDescriptorListenerBase {
 198  public:
 199   MyCBListener(base::Callback<void(int)> cb, int fds_to_send)
 200       : MyChannelDescriptorListenerBase(),
 201         cb_(cb) {
 202     }
 203
 204  protected:
 205   virtual void HandleFD(int fd) OVERRIDE {
 206     cb_.Run(fd);
 207   }
 208  private:
 209   base::Callback<void(int)> cb_;
 210 };
 211
 212 std::pair<int, int> make_socket_pair() {
 213   int pipe_fds[2];
 214   CHECK_EQ(0, HANDLE_EINTR(socketpair(AF_UNIX, SOCK_STREAM, 0, pipe_fds)));
 215   return std::pair<int, int>(pipe_fds[0], pipe_fds[1]);
 216 }
 217
 218 static void null_cb(int unused_fd) {
 219   NOTREACHED();
 220 }
 221
 222 class PipeChannelHelper {
 223  public:
 224   PipeChannelHelper(base::Thread* in_thread,
 225                     base::Thread* out_thread,
 226                     base::Callback<void(int)> cb,
 227                     int fds_to_send) :
 228       in_thread_(in_thread),
 229       out_thread_(out_thread),
 230       cb_listener_(cb, fds_to_send),
 231       null_listener_(base::Bind(&null_cb), 0) {
 232   }
 233
 234   void Init() {
 235     IPC::ChannelHandle in_handle("IN");
 236     in = IPC::Channel::CreateServer(in_handle, &null_listener_);
 237     base::FileDescriptor out_fd(
 238         in->TakeClientFileDescriptor(), false);
 239     IPC::ChannelHandle out_handle("OUT", out_fd);
 240     out = IPC::Channel::CreateClient(out_handle, &cb_listener_);
 241     // PostTask the connect calls to make sure the callbacks happens
 242     // on the right threads.
 243     in_thread_->message_loop()->PostTask(
 244         FROM_HERE,
 245         base::Bind(&PipeChannelHelper::Connect, in.get()));
 246     out_thread_->message_loop()->PostTask(
 247         FROM_HERE,
 248         base::Bind(&PipeChannelHelper::Connect, out.get()));
 249   }
 250
 251   static void DestroyChannel(scoped_ptr<IPC::Channel> *c,
 252                              base::WaitableEvent *event) {
 253     c->reset(0);
 254     event->Signal();
 255   }
 256
 257   ~PipeChannelHelper() {
 258     base::WaitableEvent a(true, false);
 259     base::WaitableEvent b(true, false);
 260     in_thread_->message_loop()->PostTask(
 261         FROM_HERE,
 262         base::Bind(&PipeChannelHelper::DestroyChannel, &in, &a));
 263     out_thread_->message_loop()->PostTask(
 264         FROM_HERE,
 265         base::Bind(&PipeChannelHelper::DestroyChannel, &out, &b));
 266     a.Wait();
 267     b.Wait();
 268   }
 269
 270   static void Connect(IPC::Channel *channel) {
 271     EXPECT_TRUE(channel->Connect());
 272   }
 273
 274   void Send(int fd) {
 275     CHECK_EQ(base::MessageLoop::current(), in_thread_->message_loop());
 276
 277     ASSERT_GE(fd, 0);
 278     base::FileDescriptor descriptor(fd, true);
 279
 280     IPC::Message* message =
 281         new IPC::Message(0, 3, IPC::Message::PRIORITY_NORMAL);
 282     IPC::ParamTraits<base::FileDescriptor>::Write(message, descriptor);
 283     ASSERT_TRUE(in->Send(message));
 284   }
 285
 286  private:
 287   scoped_ptr<IPC::Channel> in, out;
 288   base::Thread* in_thread_;
 289   base::Thread* out_thread_;
 290   MyCBListener cb_listener_;
 291   MyCBListener null_listener_;
 292 };
 293
 294 // This test is meant to provoke a kernel bug on OSX, and to prove
 295 // that the workaround for it is working. It sets up two pipes and three
 296 // threads, the producer thread creates socketpairs and sends one of the fds
 297 // over pipe1 to the middleman thread. The middleman thread simply takes the fd
 298 // sends it over pipe2 to the consumer thread. The consumer thread writes a byte
 299 // to each fd it receives and then closes the pipe. The producer thread reads
 300 // the bytes back from each pair of pipes and make sure that everything worked.
 301 // This feedback mechanism makes sure that not too many file descriptors are
 302 // in flight at the same time. For more info on the bug, see:
 303 // http://crbug.com/298276
 304 class IPCMultiSendingFdsTest : public testing::Test {
 305  public:
 306   IPCMultiSendingFdsTest() : received_(true, false) {}
 307
 308   void Producer(PipeChannelHelper* dest,
 309                 base::Thread* t,
 310                 int pipes_to_send) {
 311     for (int i = 0; i < pipes_to_send; i++) {
 312       received_.Reset();
 313       std::pair<int, int> pipe_fds = make_socket_pair();
 314       t->message_loop()->PostTask(
 315           FROM_HERE,
 316           base::Bind(&PipeChannelHelper::Send,
 317                      base::Unretained(dest),
 318                      pipe_fds.second));
 319       char tmp = 'x';
 320       CHECK_EQ(1, HANDLE_EINTR(write(pipe_fds.first, &tmp, 1)));
 321       CHECK_EQ(0, IGNORE_EINTR(close(pipe_fds.first)));
 322       received_.Wait();
 323     }
 324   }
 325
 326   void ConsumerHandleFD(int fd) {
 327     char tmp = 'y';
 328     CHECK_EQ(1, HANDLE_EINTR(read(fd, &tmp, 1)));
 329     CHECK_EQ(tmp, 'x');
 330     CHECK_EQ(0, IGNORE_EINTR(close(fd)));
 331     received_.Signal();
 332   }
 333
 334   base::Thread* CreateThread(const char* name) {
 335     base::Thread* ret = new base::Thread(name);
 336     base::Thread::Options options;
 337     options.message_loop_type = base::MessageLoop::TYPE_IO;
 338     ret->StartWithOptions(options);
 339     return ret;
 340   }
 341
 342   void Run() {
 343     // On my mac, this test fails roughly 35 times per
 344     // million sends with low load, but much more with high load.
 345     // Unless the workaround is in place. With 10000 sends, we
 346     // should see at least a 3% failure rate.
 347     const int pipes_to_send = 20000;
 348     scoped_ptr<base::Thread> producer(CreateThread("producer"));
 349     scoped_ptr<base::Thread> middleman(CreateThread("middleman"));
 350     scoped_ptr<base::Thread> consumer(CreateThread("consumer"));
 351     PipeChannelHelper pipe1(
 352         middleman.get(),
 353         consumer.get(),
 354         base::Bind(&IPCMultiSendingFdsTest::ConsumerHandleFD,
 355                    base::Unretained(this)),
 356         pipes_to_send);
 357     PipeChannelHelper pipe2(
 358         producer.get(),
 359         middleman.get(),
 360         base::Bind(&PipeChannelHelper::Send, base::Unretained(&pipe1)),
 361         pipes_to_send);
 362     pipe1.Init();
 363     pipe2.Init();
 364     Producer(&pipe2, producer.get(), pipes_to_send);
 365   }
 366
 367  private:
 368   base::WaitableEvent received_;
 369 };
 370
 371 TEST_F(IPCMultiSendingFdsTest, StressTest) {
 372   Run();
 373 }
 374
 375 }  // namespace
 376
 377 #endif  // defined(OS_POSIX)