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content / public / browser / browser_message_filter.cc [blame]
// Copyright 2012 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "content/public/browser/browser_message_filter.h"
#include "base/check_op.h"
#include "base/command_line.h"
#include "base/debug/dump_without_crashing.h"
#include "base/functional/bind.h"
#include "base/functional/callback_helpers.h"
#include "base/notreached.h"
#include "base/process/process_handle.h"
#include "base/task/sequenced_task_runner.h"
#include "base/task/task_runner.h"
#include "build/build_config.h"
#include "content/browser/browser_child_process_host_impl.h"
#include "content/browser/child_process_launcher.h"
#include "content/public/browser/browser_thread.h"
#include "content/public/common/content_switches.h"
#include "content/public/common/result_codes.h"
#include "ipc/ipc_sync_message.h"
#include "ipc/message_filter.h"
using content::BrowserMessageFilter;
namespace content {
class BrowserMessageFilter::Internal : public IPC::MessageFilter {
public:
explicit Internal(BrowserMessageFilter* filter) : filter_(filter) {}
Internal(const Internal&) = delete;
Internal& operator=(const Internal&) = delete;
private:
~Internal() override {}
// IPC::MessageFilter implementation:
void OnFilterAdded(IPC::Channel* channel) override {
filter_->sender_ = channel;
filter_->OnFilterAdded(channel);
}
void OnFilterRemoved() override {
for (auto& callback : filter_->filter_removed_callbacks_)
std::move(callback).Run();
filter_->filter_removed_callbacks_.clear();
filter_->OnFilterRemoved();
}
void OnChannelClosing() override {
filter_->sender_ = nullptr;
filter_->OnChannelClosing();
}
void OnChannelError() override { filter_->OnChannelError(); }
void OnChannelConnected(int32_t peer_pid) override {
filter_->peer_process_ = base::Process::OpenWithExtraPrivileges(peer_pid);
filter_->OnChannelConnected(peer_pid);
}
bool OnMessageReceived(const IPC::Message& message) override {
DCHECK_CURRENTLY_ON(BrowserThread::IO);
BrowserThread::ID thread = BrowserThread::IO;
filter_->OverrideThreadForMessage(message, &thread);
scoped_refptr<base::SequencedTaskRunner> destination;
if (thread == BrowserThread::UI) {
destination = GetUIThreadTaskRunner({});
} else {
DCHECK_EQ(thread, BrowserThread::IO);
destination = filter_->OverrideTaskRunnerForMessage(message);
// Neither override kicked in, dispatch the message immediately from the
// IO thread.
if (!destination)
return DispatchMessage(message);
}
DCHECK(destination);
destination->PostTask(
FROM_HERE,
base::BindOnce(base::IgnoreResult(&Internal::DispatchMessage), this,
message));
return true;
}
bool GetSupportedMessageClasses(
std::vector<uint32_t>* supported_message_classes) const override {
supported_message_classes->assign(
filter_->message_classes_to_filter().begin(),
filter_->message_classes_to_filter().end());
return true;
}
// Dispatches a message to the derived class.
bool DispatchMessage(const IPC::Message& message) {
bool rv = filter_->OnMessageReceived(message);
DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO) || rv) <<
"Must handle messages that were dispatched to another thread!";
return rv;
}
scoped_refptr<BrowserMessageFilter> filter_;
};
BrowserMessageFilter::BrowserMessageFilter(uint32_t message_class_to_filter)
: message_classes_to_filter_(1, message_class_to_filter) {}
BrowserMessageFilter::BrowserMessageFilter(
const uint32_t* message_classes_to_filter,
size_t num_message_classes_to_filter)
: message_classes_to_filter_(
message_classes_to_filter,
message_classes_to_filter + num_message_classes_to_filter) {
DCHECK(num_message_classes_to_filter);
}
base::ProcessHandle BrowserMessageFilter::PeerHandle() {
return peer_process_.Handle();
}
void BrowserMessageFilter::OnDestruct() const {
delete this;
}
bool BrowserMessageFilter::Send(IPC::Message* message) {
std::unique_ptr<IPC::Message> msg(message);
// We don't support sending synchronous messages from the browser. If we
// really needed it, we can make this class derive from SyncMessageFilter
// but it seems better to not allow sending synchronous messages from the
// browser, since it might allow a corrupt/malicious renderer to hang us.
DCHECK(!msg->is_sync())
<< "Can't send sync message through BrowserMessageFilter!";
if (!BrowserThread::CurrentlyOn(BrowserThread::IO)) {
GetIOThreadTaskRunner({})->PostTask(
FROM_HERE,
base::BindOnce(base::IgnoreResult(&BrowserMessageFilter::Send), this,
msg.release()));
return true;
}
if (sender_)
return sender_->Send(msg.release());
return false;
}
scoped_refptr<base::SequencedTaskRunner>
BrowserMessageFilter::OverrideTaskRunnerForMessage(
const IPC::Message& message) {
return nullptr;
}
void BrowserMessageFilter::ShutdownForBadMessage() {
base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
if (command_line->HasSwitch(switches::kDisableKillAfterBadIPC))
return;
if (base::Process::Current().Handle() == peer_process_.Handle()) {
// Just crash in single process. Matches RenderProcessHostImpl behavior.
CHECK(false);
}
ChildProcessLauncher::TerminateProcess(
peer_process_, content::RESULT_CODE_KILLED_BAD_MESSAGE);
// Report a crash, since none will be generated by the killed renderer.
base::debug::DumpWithoutCrashing();
}
BrowserMessageFilter::~BrowserMessageFilter() {
}
IPC::MessageFilter* BrowserMessageFilter::GetFilter() {
// We create this on demand so that if a filter is used in a unit test but
// never attached to a channel, we don't leak Internal and this;
DCHECK(!internal_) << "Should only be called once.";
internal_ = new Internal(this);
return internal_;
}
} // namespace content