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content / browser / media / midi_host.cc [blame]
// Copyright 2013 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/browser/media/midi_host.h"
#include "base/containers/contains.h"
#include "base/functional/bind.h"
#include "base/functional/callback_helpers.h"
#include "base/memory/ptr_util.h"
#include "base/process/process.h"
#include "base/trace_event/trace_event.h"
#include "content/browser/bad_message.h"
#include "content/browser/browser_main_loop.h"
#include "content/browser/child_process_security_policy_impl.h"
#include "content/public/browser/content_browser_client.h"
#include "content/public/browser/render_process_host.h"
#include "media/midi/message_util.h"
#include "media/midi/midi_message_queue.h"
#include "media/midi/midi_service.h"
#include "mojo/public/cpp/bindings/self_owned_receiver.h"
#include "third_party/blink/public/common/features.h"
namespace content {
namespace {
// The total number of bytes which we're allowed to send to the OS
// before knowing that they have been successfully sent.
const size_t kMaxInFlightBytes = 10 * 1024 * 1024; // 10 MB.
// We keep track of the number of bytes successfully sent to
// the hardware. Every once in a while we report back to the renderer
// the number of bytes sent since the last report. This threshold determines
// how many bytes will be sent before reporting back to the renderer.
const size_t kAcknowledgementThresholdBytes = 1024 * 1024; // 1 MB.
} // namespace
using midi::IsDataByte;
using midi::IsSystemRealTimeMessage;
using midi::IsValidWebMIDIData;
using midi::kEndOfSysExByte;
using midi::kSysExByte;
using midi::mojom::PortState;
using midi::mojom::Result;
MidiHost::MidiHost(int renderer_process_id, midi::MidiService* midi_service)
: renderer_process_id_(renderer_process_id),
has_midi_permission_(false),
has_midi_sysex_permission_(false),
midi_service_(midi_service),
sent_bytes_in_flight_(0),
bytes_sent_since_last_acknowledgement_(0),
output_port_count_(0) {
DCHECK(midi_service_);
}
MidiHost::~MidiHost() {
DCHECK_CURRENTLY_ON(BrowserThread::IO);
if (midi_client_ && midi_service_)
EndSession();
}
// static
void MidiHost::BindReceiver(
int render_process_id,
midi::MidiService* midi_service,
mojo::PendingReceiver<midi::mojom::MidiSessionProvider> receiver) {
DCHECK_CURRENTLY_ON(BrowserThread::IO);
mojo::MakeSelfOwnedReceiver(
base::WrapUnique(new MidiHost(render_process_id, midi_service)),
std::move(receiver));
}
void MidiHost::CompleteStartSession(Result result) {
DCHECK_CURRENTLY_ON(BrowserThread::IO);
DCHECK(midi_client_);
if (result == Result::OK)
midi_session_.Bind(std::move(pending_session_receiver_));
midi_client_->SessionStarted(result);
}
void MidiHost::AddInputPort(const midi::mojom::PortInfo& info) {
base::AutoLock auto_lock(messages_queues_lock_);
// MidiMessageQueue is created later in ReceiveMidiData().
received_messages_queues_.push_back(nullptr);
CallClient(&midi::mojom::MidiSessionClient::AddInputPort,
midi::mojom::PortInfo::New(info));
}
void MidiHost::AddOutputPort(const midi::mojom::PortInfo& info) {
base::AutoLock auto_lock(output_port_count_lock_);
output_port_count_++;
CallClient(&midi::mojom::MidiSessionClient::AddOutputPort,
midi::mojom::PortInfo::New(info));
}
void MidiHost::SetInputPortState(uint32_t port, PortState state) {
CallClient(&midi::mojom::MidiSessionClient::SetInputPortState, port, state);
}
void MidiHost::SetOutputPortState(uint32_t port, PortState state) {
CallClient(&midi::mojom::MidiSessionClient::SetOutputPortState, port, state);
}
void MidiHost::ReceiveMidiData(uint32_t port,
const uint8_t* data,
size_t length,
base::TimeTicks timestamp) {
TRACE_EVENT0("midi", "MidiHost::ReceiveMidiData");
base::AutoLock auto_lock(messages_queues_lock_);
if (received_messages_queues_.size() <= port)
return;
// Lazy initialization
if (received_messages_queues_[port] == nullptr)
received_messages_queues_[port] =
std::make_unique<midi::MidiMessageQueue>(true);
received_messages_queues_[port]->Add(data, length);
std::vector<uint8_t> message;
while (true) {
received_messages_queues_[port]->Get(&message);
if (message.empty())
break;
if (base::FeatureList::IsEnabled(blink::features::kBlockMidiByDefault)) {
// MIDI devices may send messages even if the renderer doesn't have
// permission to receive them. Don't kill the renderer as SendData() does.
if (!has_midi_permission_) {
// TODO(crbug.com/40637524): This should check permission with the Frame
// and not the Process.
has_midi_permission_ =
ChildProcessSecurityPolicyImpl::GetInstance()->CanSendMidiMessage(
renderer_process_id_);
if (!has_midi_permission_) {
continue;
}
}
}
// MIDI devices may send a system exclusive messages even if the renderer
// doesn't have a permission to receive it. Don't kill the renderer as
// SendData() does.
if (message[0] == kSysExByte) {
if (!has_midi_sysex_permission_) {
// TODO(crbug.com/40637524): This should check permission with the Frame
// and not the Process.
has_midi_sysex_permission_ =
ChildProcessSecurityPolicyImpl::GetInstance()
->CanSendMidiSysExMessage(renderer_process_id_);
if (!has_midi_sysex_permission_) {
continue;
}
}
}
// Send to the renderer.
CallClient(&midi::mojom::MidiSessionClient::DataReceived, port, message,
timestamp);
}
}
void MidiHost::AccumulateMidiBytesSent(size_t n) {
{
base::AutoLock auto_lock(in_flight_lock_);
if (n <= sent_bytes_in_flight_)
sent_bytes_in_flight_ -= n;
}
if (bytes_sent_since_last_acknowledgement_ + n >=
bytes_sent_since_last_acknowledgement_)
bytes_sent_since_last_acknowledgement_ += n;
if (bytes_sent_since_last_acknowledgement_ >=
kAcknowledgementThresholdBytes) {
CallClient(&midi::mojom::MidiSessionClient::AcknowledgeSentData,
bytes_sent_since_last_acknowledgement_);
bytes_sent_since_last_acknowledgement_ = 0;
}
}
void MidiHost::Detach() {
midi_service_ = nullptr;
}
void MidiHost::StartSession(
mojo::PendingReceiver<midi::mojom::MidiSession> session_receiver,
mojo::PendingRemote<midi::mojom::MidiSessionClient> client) {
DCHECK_CURRENTLY_ON(BrowserThread::IO);
DCHECK(!pending_session_receiver_);
// Checks to see if |midi_session_| isn't already bound to another
// MidiSessionRequest.
pending_session_receiver_ = std::move(session_receiver);
DCHECK(!midi_client_);
midi_client_.Bind(std::move(client));
midi_client_.set_disconnect_handler(
base::BindOnce(&MidiHost::EndSession, base::Unretained(this)));
if (midi_service_)
midi_service_->StartSession(this);
}
void MidiHost::SendData(uint32_t port,
const std::vector<uint8_t>& data,
base::TimeTicks timestamp) {
DCHECK_CURRENTLY_ON(BrowserThread::IO);
{
base::AutoLock auto_lock(output_port_count_lock_);
if (output_port_count_ <= port) {
bad_message::ReceivedBadMessage(renderer_process_id_,
bad_message::MH_INVALID_MIDI_PORT);
return;
}
}
if (data.empty())
return;
// Blink running in a renderer checks permission to raise a SecurityError
// in JavaScript. The actual permission check for security purposes
// happens here in the browser process.
if (base::FeatureList::IsEnabled(blink::features::kBlockMidiByDefault)) {
if (!has_midi_permission_ && !base::Contains(data, kSysExByte)) {
has_midi_permission_ =
ChildProcessSecurityPolicyImpl::GetInstance()->CanSendMidiMessage(
renderer_process_id_);
if (!has_midi_permission_) {
bad_message::ReceivedBadMessage(renderer_process_id_,
bad_message::MH_MIDI_PERMISSION);
return;
}
}
}
// Check `has_midi_sysex_permission_` here to avoid searching kSysExByte in
// large bulk data transfers for correct uses.
if (!has_midi_sysex_permission_ && base::Contains(data, kSysExByte)) {
has_midi_sysex_permission_ =
ChildProcessSecurityPolicyImpl::GetInstance()->CanSendMidiSysExMessage(
renderer_process_id_);
if (!has_midi_sysex_permission_) {
bad_message::ReceivedBadMessage(renderer_process_id_,
bad_message::MH_MIDI_SYSEX_PERMISSION);
return;
}
}
if (!IsValidWebMIDIData(data))
return;
{
base::AutoLock auto_lock(in_flight_lock_);
// Sanity check that we won't send too much data.
// TODO(yukawa): Consider to send an error event back to the renderer
// after some future discussion in W3C.
if (data.size() + sent_bytes_in_flight_ > kMaxInFlightBytes)
return;
sent_bytes_in_flight_ += data.size();
}
if (midi_service_)
midi_service_->DispatchSendMidiData(this, port, data, timestamp);
}
template <typename Method, typename... Params>
void MidiHost::CallClient(Method method, Params... params) {
if (!BrowserThread::CurrentlyOn(BrowserThread::IO)) {
GetIOThreadTaskRunner({})->PostTask(
FROM_HERE, base::BindOnce(&MidiHost::CallClient<Method, Params...>,
weak_ptr_factory_.GetWeakPtr(), method,
std::move(params)...));
return;
}
(midi_client_.get()->*method)(std::move(params)...);
}
void MidiHost::EndSession() {
if (midi_service_)
midi_service_->EndSession(this);
midi_client_.reset();
midi_session_.reset();
}
} // namespace content