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   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   void OnChannelError() override {
  64     base::MessageLoop::current()->Quit();
  65   }
  66
  67  protected:
  68   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   void HandleFD(int fd) override { cb_.Run(fd); }
 206  private:
 207   base::Callback<void(int)> cb_;
 208 };
 209
 210 std::pair<int, int> make_socket_pair() {
 211   int pipe_fds[2];
 212   CHECK_EQ(0, HANDLE_EINTR(socketpair(AF_UNIX, SOCK_STREAM, 0, pipe_fds)));
 213   return std::pair<int, int>(pipe_fds[0], pipe_fds[1]);
 214 }
 215
 216 static void null_cb(int unused_fd) {
 217   NOTREACHED();
 218 }
 219
 220 class PipeChannelHelper {
 221  public:
 222   PipeChannelHelper(base::Thread* in_thread,
 223                     base::Thread* out_thread,
 224                     base::Callback<void(int)> cb,
 225                     int fds_to_send) :
 226       in_thread_(in_thread),
 227       out_thread_(out_thread),
 228       cb_listener_(cb, fds_to_send),
 229       null_listener_(base::Bind(&null_cb), 0) {
 230   }
 231
 232   void Init() {
 233     IPC::ChannelHandle in_handle("IN");
 234     in = IPC::Channel::CreateServer(in_handle, &null_listener_);
 235     IPC::ChannelHandle out_handle(
 236         "OUT", base::FileDescriptor(in->TakeClientFileDescriptor()));
 237     out = IPC::Channel::CreateClient(out_handle, &cb_listener_);
 238     // PostTask the connect calls to make sure the callbacks happens
 239     // on the right threads.
 240     in_thread_->message_loop()->PostTask(
 241         FROM_HERE,
 242         base::Bind(&PipeChannelHelper::Connect, in.get()));
 243     out_thread_->message_loop()->PostTask(
 244         FROM_HERE,
 245         base::Bind(&PipeChannelHelper::Connect, out.get()));
 246   }
 247
 248   static void DestroyChannel(scoped_ptr<IPC::Channel> *c,
 249                              base::WaitableEvent *event) {
 250     c->reset(0);
 251     event->Signal();
 252   }
 253
 254   ~PipeChannelHelper() {
 255     base::WaitableEvent a(true, false);
 256     base::WaitableEvent b(true, false);
 257     in_thread_->message_loop()->PostTask(
 258         FROM_HERE,
 259         base::Bind(&PipeChannelHelper::DestroyChannel, &in, &a));
 260     out_thread_->message_loop()->PostTask(
 261         FROM_HERE,
 262         base::Bind(&PipeChannelHelper::DestroyChannel, &out, &b));
 263     a.Wait();
 264     b.Wait();
 265   }
 266
 267   static void Connect(IPC::Channel *channel) {
 268     EXPECT_TRUE(channel->Connect());
 269   }
 270
 271   void Send(int fd) {
 272     CHECK_EQ(base::MessageLoop::current(), in_thread_->message_loop());
 273
 274     ASSERT_GE(fd, 0);
 275     base::FileDescriptor descriptor(fd, true);
 276
 277     IPC::Message* message =
 278         new IPC::Message(0, 3, IPC::Message::PRIORITY_NORMAL);
 279     IPC::ParamTraits<base::FileDescriptor>::Write(message, descriptor);
 280     ASSERT_TRUE(in->Send(message));
 281   }
 282
 283  private:
 284   scoped_ptr<IPC::Channel> in, out;
 285   base::Thread* in_thread_;
 286   base::Thread* out_thread_;
 287   MyCBListener cb_listener_;
 288   MyCBListener null_listener_;
 289 };
 290
 291 // This test is meant to provoke a kernel bug on OSX, and to prove
 292 // that the workaround for it is working. It sets up two pipes and three
 293 // threads, the producer thread creates socketpairs and sends one of the fds
 294 // over pipe1 to the middleman thread. The middleman thread simply takes the fd
 295 // sends it over pipe2 to the consumer thread. The consumer thread writes a byte
 296 // to each fd it receives and then closes the pipe. The producer thread reads
 297 // the bytes back from each pair of pipes and make sure that everything worked.
 298 // This feedback mechanism makes sure that not too many file descriptors are
 299 // in flight at the same time. For more info on the bug, see:
 300 // http://crbug.com/298276
 301 class IPCMultiSendingFdsTest : public testing::Test {
 302  public:
 303   IPCMultiSendingFdsTest() : received_(true, false) {}
 304
 305   void Producer(PipeChannelHelper* dest,
 306                 base::Thread* t,
 307                 int pipes_to_send) {
 308     for (int i = 0; i < pipes_to_send; i++) {
 309       received_.Reset();
 310       std::pair<int, int> pipe_fds = make_socket_pair();
 311       t->message_loop()->PostTask(
 312           FROM_HERE,
 313           base::Bind(&PipeChannelHelper::Send,
 314                      base::Unretained(dest),
 315                      pipe_fds.second));
 316       char tmp = 'x';
 317       CHECK_EQ(1, HANDLE_EINTR(write(pipe_fds.first, &tmp, 1)));
 318       CHECK_EQ(0, IGNORE_EINTR(close(pipe_fds.first)));
 319       received_.Wait();
 320     }
 321   }
 322
 323   void ConsumerHandleFD(int fd) {
 324     char tmp = 'y';
 325     CHECK_EQ(1, HANDLE_EINTR(read(fd, &tmp, 1)));
 326     CHECK_EQ(tmp, 'x');
 327     CHECK_EQ(0, IGNORE_EINTR(close(fd)));
 328     received_.Signal();
 329   }
 330
 331   base::Thread* CreateThread(const char* name) {
 332     base::Thread* ret = new base::Thread(name);
 333     base::Thread::Options options;
 334     options.message_loop_type = base::MessageLoop::TYPE_IO;
 335     ret->StartWithOptions(options);
 336     return ret;
 337   }
 338
 339   void Run() {
 340     // On my mac, this test fails roughly 35 times per
 341     // million sends with low load, but much more with high load.
 342     // Unless the workaround is in place. With 10000 sends, we
 343     // should see at least a 3% failure rate.
 344     const int pipes_to_send = 20000;
 345     scoped_ptr<base::Thread> producer(CreateThread("producer"));
 346     scoped_ptr<base::Thread> middleman(CreateThread("middleman"));
 347     scoped_ptr<base::Thread> consumer(CreateThread("consumer"));
 348     PipeChannelHelper pipe1(
 349         middleman.get(),
 350         consumer.get(),
 351         base::Bind(&IPCMultiSendingFdsTest::ConsumerHandleFD,
 352                    base::Unretained(this)),
 353         pipes_to_send);
 354     PipeChannelHelper pipe2(
 355         producer.get(),
 356         middleman.get(),
 357         base::Bind(&PipeChannelHelper::Send, base::Unretained(&pipe1)),
 358         pipes_to_send);
 359     pipe1.Init();
 360     pipe2.Init();
 361     Producer(&pipe2, producer.get(), pipes_to_send);
 362   }
 363
 364  private:
 365   base::WaitableEvent received_;
 366 };
 367
 368 TEST_F(IPCMultiSendingFdsTest, StressTest) {
 369   Run();
 370 }
 371
 372 }  // namespace
 373
 374 #endif  // defined(OS_POSIX)