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.
5 #include "content/common/child_process_host_impl.h"
9 #include "base/atomic_sequence_num.h"
10 #include "base/command_line.h"
11 #include "base/files/file_path.h"
12 #include "base/logging.h"
13 #include "base/metrics/histogram.h"
14 #include "base/numerics/safe_math.h"
15 #include "base/path_service.h"
16 #include "base/process/process_metrics.h"
17 #include "base/rand_util.h"
18 #include "base/strings/stringprintf.h"
19 #include "base/third_party/dynamic_annotations/dynamic_annotations.h"
20 #include "content/common/child_process_messages.h"
21 #include "content/common/gpu/client/gpu_memory_buffer_impl_shared_memory.h"
22 #include "content/public/common/child_process_host_delegate.h"
23 #include "content/public/common/content_paths.h"
24 #include "content/public/common/content_switches.h"
25 #include "ipc/ipc_channel.h"
26 #include "ipc/ipc_logging.h"
27 #include "ipc/message_filter.h"
30 #include "base/linux_util.h"
32 #include "content/common/font_cache_dispatcher_win.h"
37 #if defined(OS_MACOSX)
38 // Given |path| identifying a Mac-style child process executable path, adjusts
39 // it to correspond to |feature|. For a child process path such as
40 // ".../Chromium Helper.app/Contents/MacOS/Chromium Helper", the transformed
41 // path for feature "NP" would be
42 // ".../Chromium Helper NP.app/Contents/MacOS/Chromium Helper NP". The new
44 base::FilePath TransformPathForFeature(const base::FilePath& path,
45 const std::string& feature) {
46 std::string basename = path.BaseName().value();
48 base::FilePath macos_path = path.DirName();
49 const char kMacOSName[] = "MacOS";
50 DCHECK_EQ(kMacOSName, macos_path.BaseName().value());
52 base::FilePath contents_path = macos_path.DirName();
53 const char kContentsName[] = "Contents";
54 DCHECK_EQ(kContentsName, contents_path.BaseName().value());
56 base::FilePath helper_app_path = contents_path.DirName();
57 const char kAppExtension[] = ".app";
58 std::string basename_app = basename;
59 basename_app.append(kAppExtension);
60 DCHECK_EQ(basename_app, helper_app_path.BaseName().value());
62 base::FilePath root_path = helper_app_path.DirName();
64 std::string new_basename = basename;
65 new_basename.append(1, ' ');
66 new_basename.append(feature);
67 std::string new_basename_app = new_basename;
68 new_basename_app.append(kAppExtension);
70 base::FilePath new_path = root_path.Append(new_basename_app)
71 .Append(kContentsName)
73 .Append(new_basename);
79 // Global atomic to generate child process unique IDs.
80 base::StaticAtomicSequenceNumber g_unique_id;
82 // Global atomic to generate gpu memory buffer unique IDs.
83 base::StaticAtomicSequenceNumber g_next_gpu_memory_buffer_id;
89 int ChildProcessHost::kInvalidUniqueID = -1;
92 ChildProcessHost* ChildProcessHost::Create(ChildProcessHostDelegate* delegate) {
93 return new ChildProcessHostImpl(delegate);
97 base::FilePath ChildProcessHost::GetChildPath(int flags) {
98 base::FilePath child_path;
100 child_path = base::CommandLine::ForCurrentProcess()->GetSwitchValuePath(
101 switches::kBrowserSubprocessPath);
103 #if defined(OS_LINUX)
104 // Use /proc/self/exe rather than our known binary path so updates
105 // can't swap out the binary from underneath us.
106 // When running under Valgrind, forking /proc/self/exe ends up forking the
107 // Valgrind executable, which then crashes. However, it's almost safe to
108 // assume that the updates won't happen while testing with Valgrind tools.
109 if (child_path.empty() && flags & CHILD_ALLOW_SELF && !RunningOnValgrind())
110 child_path = base::FilePath(base::kProcSelfExe);
113 // On most platforms, the child executable is the same as the current
115 if (child_path.empty())
116 PathService::Get(CHILD_PROCESS_EXE, &child_path);
118 #if defined(OS_MACOSX)
119 DCHECK(!(flags & CHILD_NO_PIE && flags & CHILD_ALLOW_HEAP_EXECUTION));
121 // If needed, choose an executable with special flags set that inform the
122 // kernel to enable or disable specific optional process-wide features.
123 if (flags & CHILD_NO_PIE) {
124 // "NP" is "No PIE". This results in Chromium Helper NP.app or
125 // Google Chrome Helper NP.app.
126 child_path = TransformPathForFeature(child_path, "NP");
127 } else if (flags & CHILD_ALLOW_HEAP_EXECUTION) {
128 // "EH" is "Executable Heap". A non-executable heap is only available to
129 // 32-bit processes on Mac OS X 10.7. Most code can and should run with a
130 // non-executable heap, but the "EH" feature is provided to allow code
131 // intolerant of a non-executable heap to work properly on 10.7. This
132 // results in Chromium Helper EH.app or Google Chrome Helper EH.app.
133 child_path = TransformPathForFeature(child_path, "EH");
140 ChildProcessHostImpl::ChildProcessHostImpl(ChildProcessHostDelegate* delegate)
141 : delegate_(delegate),
142 peer_handle_(base::kNullProcessHandle),
143 opening_channel_(false) {
145 AddFilter(new FontCacheDispatcher());
149 ChildProcessHostImpl::~ChildProcessHostImpl() {
150 for (size_t i = 0; i < filters_.size(); ++i) {
151 filters_[i]->OnChannelClosing();
152 filters_[i]->OnFilterRemoved();
155 base::CloseProcessHandle(peer_handle_);
158 void ChildProcessHostImpl::AddFilter(IPC::MessageFilter* filter) {
159 filters_.push_back(filter);
162 filter->OnFilterAdded(channel_.get());
165 void ChildProcessHostImpl::ForceShutdown() {
166 Send(new ChildProcessMsg_Shutdown());
169 std::string ChildProcessHostImpl::CreateChannel() {
170 channel_id_ = IPC::Channel::GenerateVerifiedChannelID(std::string());
171 channel_ = IPC::Channel::CreateServer(channel_id_, this);
172 if (!channel_->Connect())
173 return std::string();
175 for (size_t i = 0; i < filters_.size(); ++i)
176 filters_[i]->OnFilterAdded(channel_.get());
178 // Make sure these messages get sent first.
179 #if defined(IPC_MESSAGE_LOG_ENABLED)
180 bool enabled = IPC::Logging::GetInstance()->Enabled();
181 Send(new ChildProcessMsg_SetIPCLoggingEnabled(enabled));
184 opening_channel_ = true;
189 bool ChildProcessHostImpl::IsChannelOpening() {
190 return opening_channel_;
193 #if defined(OS_POSIX)
194 base::ScopedFD ChildProcessHostImpl::TakeClientFileDescriptor() {
195 return channel_->TakeClientFileDescriptor();
199 bool ChildProcessHostImpl::Send(IPC::Message* message) {
204 return channel_->Send(message);
207 void ChildProcessHostImpl::AllocateSharedMemory(
208 size_t buffer_size, base::ProcessHandle child_process_handle,
209 base::SharedMemoryHandle* shared_memory_handle) {
210 base::SharedMemory shared_buf;
211 if (!shared_buf.CreateAnonymous(buffer_size)) {
212 *shared_memory_handle = base::SharedMemory::NULLHandle();
213 NOTREACHED() << "Cannot create shared memory buffer";
216 shared_buf.GiveToProcess(child_process_handle, shared_memory_handle);
219 int ChildProcessHostImpl::GenerateChildProcessUniqueId() {
220 // This function must be threadsafe.
222 // Historically, this function returned ids started with 1, so in several
223 // places in the code a value of 0 (rather than kInvalidUniqueID) was used as
224 // an invalid value. So we retain those semantics.
225 int id = g_unique_id.GetNext() + 1;
228 CHECK_NE(kInvalidUniqueID, id);
233 bool ChildProcessHostImpl::OnMessageReceived(const IPC::Message& msg) {
234 #ifdef IPC_MESSAGE_LOG_ENABLED
235 IPC::Logging* logger = IPC::Logging::GetInstance();
236 if (msg.type() == IPC_LOGGING_ID) {
237 logger->OnReceivedLoggingMessage(msg);
241 if (logger->Enabled())
242 logger->OnPreDispatchMessage(msg);
245 bool handled = false;
246 for (size_t i = 0; i < filters_.size(); ++i) {
247 if (filters_[i]->OnMessageReceived(msg)) {
255 IPC_BEGIN_MESSAGE_MAP(ChildProcessHostImpl, msg)
256 IPC_MESSAGE_HANDLER(ChildProcessHostMsg_ShutdownRequest,
258 IPC_MESSAGE_HANDLER(ChildProcessHostMsg_SyncAllocateSharedMemory,
259 OnAllocateSharedMemory)
260 IPC_MESSAGE_HANDLER_DELAY_REPLY(
261 ChildProcessHostMsg_SyncAllocateGpuMemoryBuffer,
262 OnAllocateGpuMemoryBuffer)
263 IPC_MESSAGE_HANDLER(ChildProcessHostMsg_DeletedGpuMemoryBuffer,
264 OnDeletedGpuMemoryBuffer)
265 IPC_MESSAGE_UNHANDLED(handled = false)
266 IPC_END_MESSAGE_MAP()
269 handled = delegate_->OnMessageReceived(msg);
272 #ifdef IPC_MESSAGE_LOG_ENABLED
273 if (logger->Enabled())
274 logger->OnPostDispatchMessage(msg, channel_id_);
279 void ChildProcessHostImpl::OnChannelConnected(int32 peer_pid) {
281 !base::OpenPrivilegedProcessHandle(peer_pid, &peer_handle_)) {
282 peer_handle_ = delegate_->GetHandle();
283 DCHECK(peer_handle_);
285 opening_channel_ = false;
286 delegate_->OnChannelConnected(peer_pid);
287 for (size_t i = 0; i < filters_.size(); ++i)
288 filters_[i]->OnChannelConnected(peer_pid);
291 void ChildProcessHostImpl::OnChannelError() {
292 opening_channel_ = false;
293 delegate_->OnChannelError();
295 for (size_t i = 0; i < filters_.size(); ++i)
296 filters_[i]->OnChannelError();
298 // This will delete host_, which will also destroy this!
299 delegate_->OnChildDisconnected();
302 void ChildProcessHostImpl::OnBadMessageReceived(const IPC::Message& message) {
303 delegate_->OnBadMessageReceived(message);
306 void ChildProcessHostImpl::OnAllocateSharedMemory(
308 base::SharedMemoryHandle* handle) {
309 AllocateSharedMemory(buffer_size, peer_handle_, handle);
312 void ChildProcessHostImpl::OnShutdownRequest() {
313 if (delegate_->CanShutdown())
314 Send(new ChildProcessMsg_Shutdown());
317 void ChildProcessHostImpl::OnAllocateGpuMemoryBuffer(
320 gfx::GpuMemoryBuffer::Format format,
321 gfx::GpuMemoryBuffer::Usage usage,
322 IPC::Message* reply) {
323 base::CheckedNumeric<int> size = width;
325 if (!size.IsValid()) {
326 GpuMemoryBufferAllocated(reply, gfx::GpuMemoryBufferHandle());
330 // TODO(reveman): Add support for other types of GpuMemoryBuffers.
331 if (!GpuMemoryBufferImplSharedMemory::IsConfigurationSupported(
332 gfx::Size(width, height), format, usage)) {
333 GpuMemoryBufferAllocated(reply, gfx::GpuMemoryBufferHandle());
337 // Note: It is safe to use base::Unretained here as the shared memory
338 // implementation of AllocateForChildProcess() calls this synchronously.
339 GpuMemoryBufferImplSharedMemory::AllocateForChildProcess(
340 g_next_gpu_memory_buffer_id.GetNext(),
341 gfx::Size(width, height),
344 base::Bind(&ChildProcessHostImpl::GpuMemoryBufferAllocated,
345 base::Unretained(this),
349 void ChildProcessHostImpl::OnDeletedGpuMemoryBuffer(
350 gfx::GpuMemoryBufferId id,
352 // Note: Nothing to do here as ownership of shared memory backed
353 // GpuMemoryBuffers is passed with IPC.
356 void ChildProcessHostImpl::GpuMemoryBufferAllocated(
358 const gfx::GpuMemoryBufferHandle& handle) {
359 ChildProcessHostMsg_SyncAllocateGpuMemoryBuffer::WriteReplyParams(reply,
364 } // namespace content