| /* |
| * Copyright 2004 The WebRTC Project Authors. All rights reserved. |
| * |
| * Use of this source code is governed by a BSD-style license |
| * that can be found in the LICENSE file in the root of the source |
| * tree. An additional intellectual property rights grant can be found |
| * in the file PATENTS. All contributing project authors may |
| * be found in the AUTHORS file in the root of the source tree. |
| */ |
| |
| #include "webrtc/p2p/base/p2ptransportchannel.h" |
| |
| #include <algorithm> |
| #include <set> |
| |
| #include "webrtc/base/common.h" |
| #include "webrtc/base/crc32.h" |
| #include "webrtc/base/logging.h" |
| #include "webrtc/base/stringencode.h" |
| #include "webrtc/p2p/base/candidate.h" |
| #include "webrtc/p2p/base/candidatepairinterface.h" |
| #include "webrtc/p2p/base/common.h" |
| #include "webrtc/p2p/base/relayport.h" // For RELAY_PORT_TYPE. |
| #include "webrtc/p2p/base/stunport.h" // For STUN_PORT_TYPE. |
| #include "webrtc/system_wrappers/include/field_trial.h" |
| |
| namespace { |
| |
| // messages for queuing up work for ourselves |
| enum { |
| MSG_SORT_AND_UPDATE_STATE = 1, |
| MSG_CHECK_AND_PING, |
| MSG_REGATHER_ON_FAILED_NETWORKS |
| }; |
| |
| // The minimum improvement in RTT that justifies a switch. |
| const int kMinImprovement = 10; |
| |
| bool IsRelayRelay(const cricket::Connection* conn) { |
| return conn->local_candidate().type() == cricket::RELAY_PORT_TYPE && |
| conn->remote_candidate().type() == cricket::RELAY_PORT_TYPE; |
| } |
| |
| bool IsUdp(cricket::Connection* conn) { |
| return conn->local_candidate().relay_protocol() == cricket::UDP_PROTOCOL_NAME; |
| } |
| |
| cricket::PortInterface::CandidateOrigin GetOrigin(cricket::PortInterface* port, |
| cricket::PortInterface* origin_port) { |
| if (!origin_port) |
| return cricket::PortInterface::ORIGIN_MESSAGE; |
| else if (port == origin_port) |
| return cricket::PortInterface::ORIGIN_THIS_PORT; |
| else |
| return cricket::PortInterface::ORIGIN_OTHER_PORT; |
| } |
| |
| } // unnamed namespace |
| |
| namespace cricket { |
| |
| // When the socket is unwritable, we will use 10 Kbps (ignoring IP+UDP headers) |
| // for pinging. When the socket is writable, we will use only 1 Kbps because |
| // we don't want to degrade the quality on a modem. These numbers should work |
| // well on a 28.8K modem, which is the slowest connection on which the voice |
| // quality is reasonable at all. |
| static const int PING_PACKET_SIZE = 60 * 8; |
| // STRONG_PING_INTERVAL (480ms) is applied when the selected connection is both |
| // writable and receiving. |
| static const int STRONG_PING_INTERVAL = 1000 * PING_PACKET_SIZE / 1000; |
| // WEAK_PING_INTERVAL (48ms) is applied when the selected connection is either |
| // not writable or not receiving. |
| const int WEAK_PING_INTERVAL = 1000 * PING_PACKET_SIZE / 10000; |
| |
| // Writable connections are pinged at a faster rate while stabilizing. |
| const int STABILIZING_WRITABLE_CONNECTION_PING_INTERVAL = 900; // ms |
| |
| // Writable connections are pinged at a slower rate once stabilized. |
| const int STABLE_WRITABLE_CONNECTION_PING_INTERVAL = 2500; // ms |
| |
| static const int MIN_CHECK_RECEIVING_INTERVAL = 50; // ms |
| |
| static const int RECEIVING_SWITCHING_DELAY = 1000; // ms |
| |
| // We periodically check if any existing networks do not have any connection |
| // and regather on those networks. |
| static const int DEFAULT_REGATHER_ON_FAILED_NETWORKS_INTERVAL = 5 * 60 * 1000; |
| |
| static constexpr int DEFAULT_BACKUP_CONNECTION_PING_INTERVAL = 25 * 1000; |
| |
| static constexpr int a_is_better = 1; |
| static constexpr int b_is_better = -1; |
| |
| P2PTransportChannel::P2PTransportChannel(const std::string& transport_name, |
| int component, |
| P2PTransport* transport, |
| PortAllocator* allocator) |
| : P2PTransportChannel(transport_name, component, allocator) {} |
| |
| P2PTransportChannel::P2PTransportChannel(const std::string& transport_name, |
| int component, |
| PortAllocator* allocator) |
| : TransportChannelImpl(transport_name, component), |
| allocator_(allocator), |
| worker_thread_(rtc::Thread::Current()), |
| incoming_only_(false), |
| error_(0), |
| sort_dirty_(false), |
| remote_ice_mode_(ICEMODE_FULL), |
| ice_role_(ICEROLE_UNKNOWN), |
| tiebreaker_(0), |
| gathering_state_(kIceGatheringNew), |
| check_receiving_interval_(MIN_CHECK_RECEIVING_INTERVAL * 5), |
| config_(MIN_CHECK_RECEIVING_INTERVAL * 50 /* receiving_timeout */, |
| DEFAULT_BACKUP_CONNECTION_PING_INTERVAL, |
| GATHER_ONCE /* continual_gathering_policy */, |
| false /* prioritize_most_likely_candidate_pairs */, |
| STABLE_WRITABLE_CONNECTION_PING_INTERVAL, |
| true /* presume_writable_when_fully_relayed */, |
| DEFAULT_REGATHER_ON_FAILED_NETWORKS_INTERVAL, |
| RECEIVING_SWITCHING_DELAY) { |
| uint32_t weak_ping_interval = ::strtoul( |
| webrtc::field_trial::FindFullName("WebRTC-StunInterPacketDelay").c_str(), |
| nullptr, 10); |
| if (weak_ping_interval) { |
| weak_ping_interval_ = static_cast<int>(weak_ping_interval); |
| } |
| } |
| |
| P2PTransportChannel::~P2PTransportChannel() { |
| ASSERT(worker_thread_ == rtc::Thread::Current()); |
| } |
| |
| // Add the allocator session to our list so that we know which sessions |
| // are still active. |
| void P2PTransportChannel::AddAllocatorSession( |
| std::unique_ptr<PortAllocatorSession> session) { |
| ASSERT(worker_thread_ == rtc::Thread::Current()); |
| |
| session->set_generation(static_cast<uint32_t>(allocator_sessions_.size())); |
| session->SignalPortReady.connect(this, &P2PTransportChannel::OnPortReady); |
| session->SignalPortsPruned.connect(this, &P2PTransportChannel::OnPortsPruned); |
| session->SignalCandidatesReady.connect( |
| this, &P2PTransportChannel::OnCandidatesReady); |
| session->SignalCandidatesRemoved.connect( |
| this, &P2PTransportChannel::OnCandidatesRemoved); |
| session->SignalCandidatesAllocationDone.connect( |
| this, &P2PTransportChannel::OnCandidatesAllocationDone); |
| if (!allocator_sessions_.empty()) { |
| allocator_session()->PruneAllPorts(); |
| } |
| allocator_sessions_.push_back(std::move(session)); |
| |
| // We now only want to apply new candidates that we receive to the ports |
| // created by this new session because these are replacing those of the |
| // previous sessions. |
| PruneAllPorts(); |
| } |
| |
| void P2PTransportChannel::AddConnection(Connection* connection) { |
| connections_.push_back(connection); |
| unpinged_connections_.insert(connection); |
| connection->set_remote_ice_mode(remote_ice_mode_); |
| connection->set_receiving_timeout(config_.receiving_timeout); |
| connection->SignalReadPacket.connect( |
| this, &P2PTransportChannel::OnReadPacket); |
| connection->SignalReadyToSend.connect( |
| this, &P2PTransportChannel::OnReadyToSend); |
| connection->SignalStateChange.connect( |
| this, &P2PTransportChannel::OnConnectionStateChange); |
| connection->SignalDestroyed.connect( |
| this, &P2PTransportChannel::OnConnectionDestroyed); |
| connection->SignalNominated.connect(this, &P2PTransportChannel::OnNominated); |
| had_connection_ = true; |
| } |
| |
| // Determines whether we should switch the selected connection to |
| // |new_connection| based the writable/receiving state, the nomination state, |
| // and the last data received time. This prevents the controlled side from |
| // switching the selected connection too frequently when the controlling side |
| // is doing aggressive nominations. The precedence of the connection switching |
| // criteria is as follows: |
| // i) write/receiving/connected states |
| // ii) For controlled side, |
| // a) nomination state, |
| // b) last data received time. |
| // iii) Lower cost / higher priority. |
| // iv) rtt. |
| // To further prevent switching to high-cost networks, does not switch to |
| // a high-cost connection if it is not receiving. |
| // TODO(honghaiz): Stop the aggressive nomination on the controlling side and |
| // implement the ice-renomination option. |
| bool P2PTransportChannel::ShouldSwitchSelectedConnection( |
| Connection* new_connection, |
| bool* missed_receiving_unchanged_threshold) const { |
| if (!ReadyToSend(new_connection) || selected_connection_ == new_connection) { |
| return false; |
| } |
| |
| if (selected_connection_ == nullptr) { |
| return true; |
| } |
| |
| // Do not switch to a connection that is not receiving if it has higher cost |
| // because it may be just spuriously better. |
| if (new_connection->ComputeNetworkCost() > |
| selected_connection_->ComputeNetworkCost() && |
| !new_connection->receiving()) { |
| return false; |
| } |
| |
| rtc::Optional<int64_t> receiving_unchanged_threshold( |
| rtc::TimeMillis() - config_.receiving_switching_delay.value_or(0)); |
| int cmp = CompareConnections(selected_connection_, new_connection, |
| receiving_unchanged_threshold, |
| missed_receiving_unchanged_threshold); |
| if (cmp != 0) { |
| return cmp < 0; |
| } |
| |
| // If everything else is the same, switch only if rtt has improved by |
| // a margin. |
| return new_connection->rtt() <= selected_connection_->rtt() - kMinImprovement; |
| } |
| |
| bool P2PTransportChannel::MaybeSwitchSelectedConnection( |
| Connection* new_connection, |
| const std::string& reason) { |
| bool missed_receiving_unchanged_threshold = false; |
| if (ShouldSwitchSelectedConnection(new_connection, |
| &missed_receiving_unchanged_threshold)) { |
| LOG(LS_INFO) << "Switching selected connection due to " << reason; |
| SwitchSelectedConnection(new_connection); |
| return true; |
| } |
| if (missed_receiving_unchanged_threshold && |
| config_.receiving_switching_delay) { |
| // If we do not switch to the connection because it missed the receiving |
| // threshold, the new connection is in a better receiving state than the |
| // currently selected connection. So we need to re-check whether it needs |
| // to be switched at a later time. |
| thread()->PostDelayed(RTC_FROM_HERE, *config_.receiving_switching_delay, |
| this, MSG_SORT_AND_UPDATE_STATE); |
| } |
| return false; |
| } |
| |
| void P2PTransportChannel::SetIceRole(IceRole ice_role) { |
| ASSERT(worker_thread_ == rtc::Thread::Current()); |
| if (ice_role_ != ice_role) { |
| ice_role_ = ice_role; |
| for (PortInterface* port : ports_) { |
| port->SetIceRole(ice_role); |
| } |
| // Update role on pruned ports as well, because they may still have |
| // connections alive that should be using the correct role. |
| for (PortInterface* port : pruned_ports_) { |
| port->SetIceRole(ice_role); |
| } |
| } |
| } |
| |
| void P2PTransportChannel::SetIceTiebreaker(uint64_t tiebreaker) { |
| ASSERT(worker_thread_ == rtc::Thread::Current()); |
| if (!ports_.empty() || !pruned_ports_.empty()) { |
| LOG(LS_ERROR) |
| << "Attempt to change tiebreaker after Port has been allocated."; |
| return; |
| } |
| |
| tiebreaker_ = tiebreaker; |
| } |
| |
| TransportChannelState P2PTransportChannel::GetState() const { |
| return state_; |
| } |
| |
| // A channel is considered ICE completed once there is at most one active |
| // connection per network and at least one active connection. |
| TransportChannelState P2PTransportChannel::ComputeState() const { |
| if (!had_connection_) { |
| return TransportChannelState::STATE_INIT; |
| } |
| |
| std::vector<Connection*> active_connections; |
| for (Connection* connection : connections_) { |
| if (connection->active()) { |
| active_connections.push_back(connection); |
| } |
| } |
| if (active_connections.empty()) { |
| return TransportChannelState::STATE_FAILED; |
| } |
| |
| std::set<rtc::Network*> networks; |
| for (Connection* connection : active_connections) { |
| rtc::Network* network = connection->port()->Network(); |
| if (networks.find(network) == networks.end()) { |
| networks.insert(network); |
| } else { |
| LOG_J(LS_VERBOSE, this) << "Ice not completed yet for this channel as " |
| << network->ToString() |
| << " has more than 1 connection."; |
| return TransportChannelState::STATE_CONNECTING; |
| } |
| } |
| |
| return TransportChannelState::STATE_COMPLETED; |
| } |
| |
| void P2PTransportChannel::SetIceParameters(const IceParameters& ice_params) { |
| ASSERT(worker_thread_ == rtc::Thread::Current()); |
| LOG(LS_INFO) << "Set ICE ufrag: " << ice_params.ufrag |
| << " pwd: " << ice_params.pwd << " on transport " |
| << transport_name(); |
| ice_parameters_ = ice_params; |
| // Note: Candidate gathering will restart when MaybeStartGathering is next |
| // called. |
| } |
| |
| void P2PTransportChannel::SetRemoteIceParameters( |
| const IceParameters& ice_params) { |
| ASSERT(worker_thread_ == rtc::Thread::Current()); |
| LOG(LS_INFO) << "Remote supports ICE renomination ? " |
| << ice_params.renomination; |
| IceParameters* current_ice = remote_ice(); |
| if (!current_ice || *current_ice != ice_params) { |
| // Keep the ICE credentials so that newer connections |
| // are prioritized over the older ones. |
| remote_ice_parameters_.push_back(ice_params); |
| } |
| |
| // Update the pwd of remote candidate if needed. |
| for (RemoteCandidate& candidate : remote_candidates_) { |
| if (candidate.username() == ice_params.ufrag && |
| candidate.password().empty()) { |
| candidate.set_password(ice_params.pwd); |
| } |
| } |
| // We need to update the credentials and generation for any peer reflexive |
| // candidates. |
| for (Connection* conn : connections_) { |
| conn->MaybeSetRemoteIceParametersAndGeneration( |
| ice_params, static_cast<int>(remote_ice_parameters_.size() - 1)); |
| } |
| // Updating the remote ICE candidate generation could change the sort order. |
| RequestSortAndStateUpdate(); |
| } |
| |
| void P2PTransportChannel::SetRemoteIceMode(IceMode mode) { |
| remote_ice_mode_ = mode; |
| } |
| |
| void P2PTransportChannel::SetIceConfig(const IceConfig& config) { |
| if (config_.continual_gathering_policy != config.continual_gathering_policy) { |
| if (!allocator_sessions_.empty()) { |
| LOG(LS_ERROR) << "Trying to change continual gathering policy " |
| << "when gathering has already started!"; |
| } else { |
| config_.continual_gathering_policy = config.continual_gathering_policy; |
| LOG(LS_INFO) << "Set continual_gathering_policy to " |
| << config_.continual_gathering_policy; |
| } |
| } |
| |
| if (config.backup_connection_ping_interval >= 0 && |
| config_.backup_connection_ping_interval != |
| config.backup_connection_ping_interval) { |
| config_.backup_connection_ping_interval = |
| config.backup_connection_ping_interval; |
| LOG(LS_INFO) << "Set backup connection ping interval to " |
| << config_.backup_connection_ping_interval << " milliseconds."; |
| } |
| |
| if (config.receiving_timeout >= 0 && |
| config_.receiving_timeout != config.receiving_timeout) { |
| config_.receiving_timeout = config.receiving_timeout; |
| check_receiving_interval_ = |
| std::max(MIN_CHECK_RECEIVING_INTERVAL, config_.receiving_timeout / 10); |
| |
| for (Connection* connection : connections_) { |
| connection->set_receiving_timeout(config_.receiving_timeout); |
| } |
| LOG(LS_INFO) << "Set ICE receiving timeout to " << config_.receiving_timeout |
| << " milliseconds"; |
| } |
| |
| config_.prioritize_most_likely_candidate_pairs = |
| config.prioritize_most_likely_candidate_pairs; |
| LOG(LS_INFO) << "Set ping most likely connection to " |
| << config_.prioritize_most_likely_candidate_pairs; |
| |
| if (config.stable_writable_connection_ping_interval >= 0 && |
| config_.stable_writable_connection_ping_interval != |
| config.stable_writable_connection_ping_interval) { |
| config_.stable_writable_connection_ping_interval = |
| config.stable_writable_connection_ping_interval; |
| LOG(LS_INFO) << "Set stable_writable_connection_ping_interval to " |
| << config_.stable_writable_connection_ping_interval; |
| } |
| |
| if (config.presume_writable_when_fully_relayed != |
| config_.presume_writable_when_fully_relayed) { |
| if (!connections_.empty()) { |
| LOG(LS_ERROR) << "Trying to change 'presume writable' " |
| << "while connections already exist!"; |
| } else { |
| config_.presume_writable_when_fully_relayed = |
| config.presume_writable_when_fully_relayed; |
| LOG(LS_INFO) << "Set presume writable when fully relayed to " |
| << config_.presume_writable_when_fully_relayed; |
| } |
| } |
| |
| if (config.regather_on_failed_networks_interval) { |
| config_.regather_on_failed_networks_interval = |
| config.regather_on_failed_networks_interval; |
| LOG(LS_INFO) << "Set regather_on_failed_networks_interval to " |
| << *config_.regather_on_failed_networks_interval; |
| } |
| if (config.receiving_switching_delay) { |
| config_.receiving_switching_delay = config.receiving_switching_delay; |
| LOG(LS_INFO) << "Set receiving_switching_delay to" |
| << *config_.receiving_switching_delay; |
| } |
| |
| if (config_.default_nomination_mode != config.default_nomination_mode) { |
| config_.default_nomination_mode = config.default_nomination_mode; |
| LOG(LS_INFO) << "Set default nomination mode to " |
| << static_cast<int>(config_.default_nomination_mode); |
| } |
| } |
| |
| const IceConfig& P2PTransportChannel::config() const { |
| return config_; |
| } |
| |
| void P2PTransportChannel::MaybeStartGathering() { |
| if (ice_parameters_.ufrag.empty() || ice_parameters_.pwd.empty()) { |
| LOG(LS_ERROR) << "Cannot gather candidates because ICE parameters are empty" |
| << " ufrag: " << ice_parameters_.ufrag |
| << " pwd: " << ice_parameters_.pwd; |
| return; |
| } |
| // Start gathering if we never started before, or if an ICE restart occurred. |
| if (allocator_sessions_.empty() || |
| IceCredentialsChanged(allocator_sessions_.back()->ice_ufrag(), |
| allocator_sessions_.back()->ice_pwd(), |
| ice_parameters_.ufrag, ice_parameters_.pwd)) { |
| if (gathering_state_ != kIceGatheringGathering) { |
| gathering_state_ = kIceGatheringGathering; |
| SignalGatheringState(this); |
| } |
| // Time for a new allocator. |
| std::unique_ptr<PortAllocatorSession> pooled_session = |
| allocator_->TakePooledSession(transport_name(), component(), |
| ice_parameters_.ufrag, |
| ice_parameters_.pwd); |
| if (pooled_session) { |
| AddAllocatorSession(std::move(pooled_session)); |
| PortAllocatorSession* raw_pooled_session = |
| allocator_sessions_.back().get(); |
| // Process the pooled session's existing candidates/ports, if they exist. |
| OnCandidatesReady(raw_pooled_session, |
| raw_pooled_session->ReadyCandidates()); |
| for (PortInterface* port : allocator_sessions_.back()->ReadyPorts()) { |
| OnPortReady(raw_pooled_session, port); |
| } |
| if (allocator_sessions_.back()->CandidatesAllocationDone()) { |
| OnCandidatesAllocationDone(raw_pooled_session); |
| } |
| } else { |
| AddAllocatorSession(allocator_->CreateSession( |
| transport_name(), component(), ice_parameters_.ufrag, |
| ice_parameters_.pwd)); |
| LOG(LS_INFO) << "Start getting ports"; |
| allocator_sessions_.back()->StartGettingPorts(); |
| } |
| } |
| } |
| |
| // A new port is available, attempt to make connections for it |
| void P2PTransportChannel::OnPortReady(PortAllocatorSession *session, |
| PortInterface* port) { |
| ASSERT(worker_thread_ == rtc::Thread::Current()); |
| |
| // Set in-effect options on the new port |
| for (OptionMap::const_iterator it = options_.begin(); |
| it != options_.end(); |
| ++it) { |
| int val = port->SetOption(it->first, it->second); |
| if (val < 0) { |
| LOG_J(LS_WARNING, port) << "SetOption(" << it->first |
| << ", " << it->second |
| << ") failed: " << port->GetError(); |
| } |
| } |
| |
| // Remember the ports and candidates, and signal that candidates are ready. |
| // The session will handle this, and send an initiate/accept/modify message |
| // if one is pending. |
| |
| port->SetIceRole(ice_role_); |
| port->SetIceTiebreaker(tiebreaker_); |
| ports_.push_back(port); |
| port->SignalUnknownAddress.connect( |
| this, &P2PTransportChannel::OnUnknownAddress); |
| port->SignalDestroyed.connect(this, &P2PTransportChannel::OnPortDestroyed); |
| |
| port->SignalRoleConflict.connect( |
| this, &P2PTransportChannel::OnRoleConflict); |
| port->SignalSentPacket.connect(this, &P2PTransportChannel::OnSentPacket); |
| |
| // Attempt to create a connection from this new port to all of the remote |
| // candidates that we were given so far. |
| |
| std::vector<RemoteCandidate>::iterator iter; |
| for (iter = remote_candidates_.begin(); iter != remote_candidates_.end(); |
| ++iter) { |
| CreateConnection(port, *iter, iter->origin_port()); |
| } |
| |
| SortConnectionsAndUpdateState(); |
| } |
| |
| // A new candidate is available, let listeners know |
| void P2PTransportChannel::OnCandidatesReady( |
| PortAllocatorSession* session, |
| const std::vector<Candidate>& candidates) { |
| ASSERT(worker_thread_ == rtc::Thread::Current()); |
| for (size_t i = 0; i < candidates.size(); ++i) { |
| SignalCandidateGathered(this, candidates[i]); |
| } |
| } |
| |
| void P2PTransportChannel::OnCandidatesAllocationDone( |
| PortAllocatorSession* session) { |
| ASSERT(worker_thread_ == rtc::Thread::Current()); |
| if (config_.gather_continually()) { |
| LOG(LS_INFO) << "P2PTransportChannel: " << transport_name() |
| << ", component " << component() |
| << " gathering complete, but using continual " |
| << "gathering so not changing gathering state."; |
| return; |
| } |
| gathering_state_ = kIceGatheringComplete; |
| LOG(LS_INFO) << "P2PTransportChannel: " << transport_name() << ", component " |
| << component() << " gathering complete"; |
| SignalGatheringState(this); |
| } |
| |
| // Handle stun packets |
| void P2PTransportChannel::OnUnknownAddress( |
| PortInterface* port, |
| const rtc::SocketAddress& address, ProtocolType proto, |
| IceMessage* stun_msg, const std::string &remote_username, |
| bool port_muxed) { |
| ASSERT(worker_thread_ == rtc::Thread::Current()); |
| |
| // Port has received a valid stun packet from an address that no Connection |
| // is currently available for. See if we already have a candidate with the |
| // address. If it isn't we need to create new candidate for it. |
| |
| const Candidate* candidate = nullptr; |
| for (const Candidate& c : remote_candidates_) { |
| if (c.username() == remote_username && c.address() == address && |
| c.protocol() == ProtoToString(proto)) { |
| candidate = &c; |
| break; |
| } |
| } |
| |
| uint32_t remote_generation = 0; |
| std::string remote_password; |
| // The STUN binding request may arrive after setRemoteDescription and before |
| // adding remote candidate, so we need to set the password to the shared |
| // password and set the generation if the user name matches. |
| const IceParameters* ice_param = |
| FindRemoteIceFromUfrag(remote_username, &remote_generation); |
| // Note: if not found, the remote_generation will still be 0. |
| if (ice_param != nullptr) { |
| remote_password = ice_param->pwd; |
| } |
| |
| Candidate remote_candidate; |
| bool remote_candidate_is_new = (candidate == nullptr); |
| if (!remote_candidate_is_new) { |
| remote_candidate = *candidate; |
| } else { |
| // Create a new candidate with this address. |
| // The priority of the candidate is set to the PRIORITY attribute |
| // from the request. |
| const StunUInt32Attribute* priority_attr = |
| stun_msg->GetUInt32(STUN_ATTR_PRIORITY); |
| if (!priority_attr) { |
| LOG(LS_WARNING) << "P2PTransportChannel::OnUnknownAddress - " |
| << "No STUN_ATTR_PRIORITY found in the " |
| << "stun request message"; |
| port->SendBindingErrorResponse(stun_msg, address, STUN_ERROR_BAD_REQUEST, |
| STUN_ERROR_REASON_BAD_REQUEST); |
| return; |
| } |
| int remote_candidate_priority = priority_attr->value(); |
| |
| uint16_t network_id = 0; |
| uint16_t network_cost = 0; |
| const StunUInt32Attribute* network_attr = |
| stun_msg->GetUInt32(STUN_ATTR_NETWORK_INFO); |
| if (network_attr) { |
| uint32_t network_info = network_attr->value(); |
| network_id = static_cast<uint16_t>(network_info >> 16); |
| network_cost = static_cast<uint16_t>(network_info); |
| } |
| |
| // RFC 5245 |
| // If the source transport address of the request does not match any |
| // existing remote candidates, it represents a new peer reflexive remote |
| // candidate. |
| remote_candidate = Candidate( |
| component(), ProtoToString(proto), address, remote_candidate_priority, |
| remote_username, remote_password, PRFLX_PORT_TYPE, remote_generation, |
| "", network_id, network_cost); |
| |
| // From RFC 5245, section-7.2.1.3: |
| // The foundation of the candidate is set to an arbitrary value, different |
| // from the foundation for all other remote candidates. |
| remote_candidate.set_foundation( |
| rtc::ToString<uint32_t>(rtc::ComputeCrc32(remote_candidate.id()))); |
| } |
| |
| // RFC5245, the agent constructs a pair whose local candidate is equal to |
| // the transport address on which the STUN request was received, and a |
| // remote candidate equal to the source transport address where the |
| // request came from. |
| |
| // There shouldn't be an existing connection with this remote address. |
| // When ports are muxed, this channel might get multiple unknown address |
| // signals. In that case if the connection is already exists, we should |
| // simply ignore the signal otherwise send server error. |
| if (port->GetConnection(remote_candidate.address())) { |
| if (port_muxed) { |
| LOG(LS_INFO) << "Connection already exists for peer reflexive " |
| << "candidate: " << remote_candidate.ToString(); |
| return; |
| } else { |
| ASSERT(false); |
| port->SendBindingErrorResponse(stun_msg, address, |
| STUN_ERROR_SERVER_ERROR, |
| STUN_ERROR_REASON_SERVER_ERROR); |
| return; |
| } |
| } |
| |
| Connection* connection = |
| port->CreateConnection(remote_candidate, PortInterface::ORIGIN_THIS_PORT); |
| if (!connection) { |
| // This could happen in some scenarios. For example, a TurnPort may have |
| // had a refresh request timeout, so it won't create connections. |
| port->SendBindingErrorResponse(stun_msg, address, STUN_ERROR_SERVER_ERROR, |
| STUN_ERROR_REASON_SERVER_ERROR); |
| return; |
| } |
| |
| LOG(LS_INFO) << "Adding connection from " |
| << (remote_candidate_is_new ? "peer reflexive" : "resurrected") |
| << " candidate: " << remote_candidate.ToString(); |
| AddConnection(connection); |
| connection->HandleBindingRequest(stun_msg); |
| |
| // Update the list of connections since we just added another. We do this |
| // after sending the response since it could (in principle) delete the |
| // connection in question. |
| SortConnectionsAndUpdateState(); |
| } |
| |
| void P2PTransportChannel::OnRoleConflict(PortInterface* port) { |
| SignalRoleConflict(this); // STUN ping will be sent when SetRole is called |
| // from Transport. |
| } |
| |
| const IceParameters* P2PTransportChannel::FindRemoteIceFromUfrag( |
| const std::string& ufrag, |
| uint32_t* generation) { |
| const auto& params = remote_ice_parameters_; |
| auto it = std::find_if( |
| params.rbegin(), params.rend(), |
| [ufrag](const IceParameters& param) { return param.ufrag == ufrag; }); |
| if (it == params.rend()) { |
| // Not found. |
| return nullptr; |
| } |
| *generation = params.rend() - it - 1; |
| return &(*it); |
| } |
| |
| void P2PTransportChannel::OnNominated(Connection* conn) { |
| ASSERT(worker_thread_ == rtc::Thread::Current()); |
| ASSERT(ice_role_ == ICEROLE_CONTROLLED); |
| |
| if (selected_connection_ == conn) { |
| return; |
| } |
| |
| if (MaybeSwitchSelectedConnection(conn, |
| "nomination on the controlled side")) { |
| // Now that we have selected a connection, it is time to prune other |
| // connections and update the read/write state of the channel. |
| RequestSortAndStateUpdate(); |
| } else { |
| LOG(LS_INFO) |
| << "Not switching the selected connection on controlled side yet: " |
| << conn->ToString(); |
| } |
| } |
| |
| void P2PTransportChannel::AddRemoteCandidate(const Candidate& candidate) { |
| ASSERT(worker_thread_ == rtc::Thread::Current()); |
| |
| uint32_t generation = GetRemoteCandidateGeneration(candidate); |
| // If a remote candidate with a previous generation arrives, drop it. |
| if (generation < remote_ice_generation()) { |
| LOG(LS_WARNING) << "Dropping a remote candidate because its ufrag " |
| << candidate.username() |
| << " indicates it was for a previous generation."; |
| return; |
| } |
| |
| Candidate new_remote_candidate(candidate); |
| new_remote_candidate.set_generation(generation); |
| // ICE candidates don't need to have username and password set, but |
| // the code below this (specifically, ConnectionRequest::Prepare in |
| // port.cc) uses the remote candidates's username. So, we set it |
| // here. |
| if (remote_ice()) { |
| if (candidate.username().empty()) { |
| new_remote_candidate.set_username(remote_ice()->ufrag); |
| } |
| if (new_remote_candidate.username() == remote_ice()->ufrag) { |
| if (candidate.password().empty()) { |
| new_remote_candidate.set_password(remote_ice()->pwd); |
| } |
| } else { |
| // The candidate belongs to the next generation. Its pwd will be set |
| // when the new remote ICE credentials arrive. |
| LOG(LS_WARNING) << "A remote candidate arrives with an unknown ufrag: " |
| << candidate.username(); |
| } |
| } |
| |
| // If this candidate matches what was thought to be a peer reflexive |
| // candidate, we need to update the candidate priority/etc. |
| for (Connection* conn : connections_) { |
| conn->MaybeUpdatePeerReflexiveCandidate(new_remote_candidate); |
| } |
| |
| // Create connections to this remote candidate. |
| CreateConnections(new_remote_candidate, NULL); |
| |
| // Resort the connections list, which may have new elements. |
| SortConnectionsAndUpdateState(); |
| } |
| |
| void P2PTransportChannel::RemoveRemoteCandidate( |
| const Candidate& cand_to_remove) { |
| auto iter = |
| std::remove_if(remote_candidates_.begin(), remote_candidates_.end(), |
| [cand_to_remove](const Candidate& candidate) { |
| return cand_to_remove.MatchesForRemoval(candidate); |
| }); |
| if (iter != remote_candidates_.end()) { |
| LOG(LS_VERBOSE) << "Removed remote candidate " << cand_to_remove.ToString(); |
| remote_candidates_.erase(iter, remote_candidates_.end()); |
| } |
| } |
| |
| // Creates connections from all of the ports that we care about to the given |
| // remote candidate. The return value is true if we created a connection from |
| // the origin port. |
| bool P2PTransportChannel::CreateConnections(const Candidate& remote_candidate, |
| PortInterface* origin_port) { |
| ASSERT(worker_thread_ == rtc::Thread::Current()); |
| |
| // If we've already seen the new remote candidate (in the current candidate |
| // generation), then we shouldn't try creating connections for it. |
| // We either already have a connection for it, or we previously created one |
| // and then later pruned it. If we don't return, the channel will again |
| // re-create any connections that were previously pruned, which will then |
| // immediately be re-pruned, churning the network for no purpose. |
| // This only applies to candidates received over signaling (i.e. origin_port |
| // is NULL). |
| if (!origin_port && IsDuplicateRemoteCandidate(remote_candidate)) { |
| // return true to indicate success, without creating any new connections. |
| return true; |
| } |
| |
| // Add a new connection for this candidate to every port that allows such a |
| // connection (i.e., if they have compatible protocols) and that does not |
| // already have a connection to an equivalent candidate. We must be careful |
| // to make sure that the origin port is included, even if it was pruned, |
| // since that may be the only port that can create this connection. |
| bool created = false; |
| std::vector<PortInterface *>::reverse_iterator it; |
| for (it = ports_.rbegin(); it != ports_.rend(); ++it) { |
| if (CreateConnection(*it, remote_candidate, origin_port)) { |
| if (*it == origin_port) |
| created = true; |
| } |
| } |
| |
| if ((origin_port != NULL) && |
| std::find(ports_.begin(), ports_.end(), origin_port) == ports_.end()) { |
| if (CreateConnection(origin_port, remote_candidate, origin_port)) |
| created = true; |
| } |
| |
| // Remember this remote candidate so that we can add it to future ports. |
| RememberRemoteCandidate(remote_candidate, origin_port); |
| |
| return created; |
| } |
| |
| // Setup a connection object for the local and remote candidate combination. |
| // And then listen to connection object for changes. |
| bool P2PTransportChannel::CreateConnection(PortInterface* port, |
| const Candidate& remote_candidate, |
| PortInterface* origin_port) { |
| if (!port->SupportsProtocol(remote_candidate.protocol())) { |
| return false; |
| } |
| // Look for an existing connection with this remote address. If one is not |
| // found or it is found but the existing remote candidate has an older |
| // generation, then we can create a new connection for this address. |
| Connection* connection = port->GetConnection(remote_candidate.address()); |
| if (connection == nullptr || |
| connection->remote_candidate().generation() < |
| remote_candidate.generation()) { |
| // Don't create a connection if this is a candidate we received in a |
| // message and we are not allowed to make outgoing connections. |
| PortInterface::CandidateOrigin origin = GetOrigin(port, origin_port); |
| if (origin == PortInterface::ORIGIN_MESSAGE && incoming_only_) { |
| return false; |
| } |
| Connection* connection = port->CreateConnection(remote_candidate, origin); |
| if (!connection) { |
| return false; |
| } |
| AddConnection(connection); |
| LOG_J(LS_INFO, this) << "Created connection with origin=" << origin << ", (" |
| << connections_.size() << " total)"; |
| return true; |
| } |
| |
| // No new connection was created. |
| // It is not legal to try to change any of the parameters of an existing |
| // connection; however, the other side can send a duplicate candidate. |
| if (!remote_candidate.IsEquivalent(connection->remote_candidate())) { |
| LOG(INFO) << "Attempt to change a remote candidate." |
| << " Existing remote candidate: " |
| << connection->remote_candidate().ToString() |
| << "New remote candidate: " << remote_candidate.ToString(); |
| } |
| return false; |
| } |
| |
| bool P2PTransportChannel::FindConnection(Connection* connection) const { |
| std::vector<Connection*>::const_iterator citer = |
| std::find(connections_.begin(), connections_.end(), connection); |
| return citer != connections_.end(); |
| } |
| |
| uint32_t P2PTransportChannel::GetRemoteCandidateGeneration( |
| const Candidate& candidate) { |
| // If the candidate has a ufrag, use it to find the generation. |
| if (!candidate.username().empty()) { |
| uint32_t generation = 0; |
| if (!FindRemoteIceFromUfrag(candidate.username(), &generation)) { |
| // If the ufrag is not found, assume the next/future generation. |
| generation = static_cast<uint32_t>(remote_ice_parameters_.size()); |
| } |
| return generation; |
| } |
| // If candidate generation is set, use that. |
| if (candidate.generation() > 0) { |
| return candidate.generation(); |
| } |
| // Otherwise, assume the generation from remote ice parameters. |
| return remote_ice_generation(); |
| } |
| |
| // Check if remote candidate is already cached. |
| bool P2PTransportChannel::IsDuplicateRemoteCandidate( |
| const Candidate& candidate) { |
| for (size_t i = 0; i < remote_candidates_.size(); ++i) { |
| if (remote_candidates_[i].IsEquivalent(candidate)) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| // Maintain our remote candidate list, adding this new remote one. |
| void P2PTransportChannel::RememberRemoteCandidate( |
| const Candidate& remote_candidate, PortInterface* origin_port) { |
| // Remove any candidates whose generation is older than this one. The |
| // presence of a new generation indicates that the old ones are not useful. |
| size_t i = 0; |
| while (i < remote_candidates_.size()) { |
| if (remote_candidates_[i].generation() < remote_candidate.generation()) { |
| LOG(INFO) << "Pruning candidate from old generation: " |
| << remote_candidates_[i].address().ToSensitiveString(); |
| remote_candidates_.erase(remote_candidates_.begin() + i); |
| } else { |
| i += 1; |
| } |
| } |
| |
| // Make sure this candidate is not a duplicate. |
| if (IsDuplicateRemoteCandidate(remote_candidate)) { |
| LOG(INFO) << "Duplicate candidate: " << remote_candidate.ToString(); |
| return; |
| } |
| |
| // Try this candidate for all future ports. |
| remote_candidates_.push_back(RemoteCandidate(remote_candidate, origin_port)); |
| } |
| |
| // Set options on ourselves is simply setting options on all of our available |
| // port objects. |
| int P2PTransportChannel::SetOption(rtc::Socket::Option opt, int value) { |
| ASSERT(worker_thread_ == rtc::Thread::Current()); |
| OptionMap::iterator it = options_.find(opt); |
| if (it == options_.end()) { |
| options_.insert(std::make_pair(opt, value)); |
| } else if (it->second == value) { |
| return 0; |
| } else { |
| it->second = value; |
| } |
| |
| for (PortInterface* port : ports_) { |
| int val = port->SetOption(opt, value); |
| if (val < 0) { |
| // Because this also occurs deferred, probably no point in reporting an |
| // error |
| LOG(WARNING) << "SetOption(" << opt << ", " << value |
| << ") failed: " << port->GetError(); |
| } |
| } |
| return 0; |
| } |
| |
| bool P2PTransportChannel::GetOption(rtc::Socket::Option opt, int* value) { |
| ASSERT(worker_thread_ == rtc::Thread::Current()); |
| |
| const auto& found = options_.find(opt); |
| if (found == options_.end()) { |
| return false; |
| } |
| *value = found->second; |
| return true; |
| } |
| |
| // Send data to the other side, using our selected connection. |
| int P2PTransportChannel::SendPacket(const char *data, size_t len, |
| const rtc::PacketOptions& options, |
| int flags) { |
| ASSERT(worker_thread_ == rtc::Thread::Current()); |
| if (flags != 0) { |
| error_ = EINVAL; |
| return -1; |
| } |
| // If we don't think the connection is working yet, return ENOTCONN |
| // instead of sending a packet that will probably be dropped. |
| if (!ReadyToSend(selected_connection_)) { |
| error_ = ENOTCONN; |
| return -1; |
| } |
| |
| last_sent_packet_id_ = options.packet_id; |
| int sent = selected_connection_->Send(data, len, options); |
| if (sent <= 0) { |
| ASSERT(sent < 0); |
| error_ = selected_connection_->GetError(); |
| } |
| return sent; |
| } |
| |
| bool P2PTransportChannel::GetStats(ConnectionInfos *infos) { |
| ASSERT(worker_thread_ == rtc::Thread::Current()); |
| // Gather connection infos. |
| infos->clear(); |
| |
| for (Connection* connection : connections_) { |
| ConnectionInfo info = connection->stats(); |
| info.best_connection = (selected_connection_ == connection); |
| info.receiving = connection->receiving(); |
| info.writable = (connection->write_state() == Connection::STATE_WRITABLE); |
| info.timeout = |
| (connection->write_state() == Connection::STATE_WRITE_TIMEOUT); |
| info.new_connection = !connection->reported(); |
| connection->set_reported(true); |
| info.rtt = connection->rtt(); |
| info.local_candidate = connection->local_candidate(); |
| info.remote_candidate = connection->remote_candidate(); |
| info.key = connection; |
| infos->push_back(info); |
| } |
| |
| return true; |
| } |
| |
| rtc::DiffServCodePoint P2PTransportChannel::DefaultDscpValue() const { |
| OptionMap::const_iterator it = options_.find(rtc::Socket::OPT_DSCP); |
| if (it == options_.end()) { |
| return rtc::DSCP_NO_CHANGE; |
| } |
| return static_cast<rtc::DiffServCodePoint> (it->second); |
| } |
| |
| // Monitor connection states. |
| void P2PTransportChannel::UpdateConnectionStates() { |
| int64_t now = rtc::TimeMillis(); |
| |
| // We need to copy the list of connections since some may delete themselves |
| // when we call UpdateState. |
| for (Connection* c : connections_) { |
| c->UpdateState(now); |
| } |
| } |
| |
| // Prepare for best candidate sorting. |
| void P2PTransportChannel::RequestSortAndStateUpdate() { |
| if (!sort_dirty_) { |
| worker_thread_->Post(RTC_FROM_HERE, this, MSG_SORT_AND_UPDATE_STATE); |
| sort_dirty_ = true; |
| } |
| } |
| |
| void P2PTransportChannel::MaybeStartPinging() { |
| if (started_pinging_) { |
| return; |
| } |
| |
| int64_t now = rtc::TimeMillis(); |
| if (std::any_of( |
| connections_.begin(), connections_.end(), |
| [this, now](const Connection* c) { return IsPingable(c, now); })) { |
| LOG_J(LS_INFO, this) << "Have a pingable connection for the first time; " |
| << "starting to ping."; |
| thread()->Post(RTC_FROM_HERE, this, MSG_CHECK_AND_PING); |
| thread()->PostDelayed(RTC_FROM_HERE, |
| *config_.regather_on_failed_networks_interval, this, |
| MSG_REGATHER_ON_FAILED_NETWORKS); |
| started_pinging_ = true; |
| } |
| } |
| |
| // Compare two connections based on their writing, receiving, and connected |
| // states. |
| int P2PTransportChannel::CompareConnectionStates( |
| const Connection* a, |
| const Connection* b, |
| rtc::Optional<int64_t> receiving_unchanged_threshold, |
| bool* missed_receiving_unchanged_threshold) const { |
| // First, prefer a connection that's writable or presumed writable over |
| // one that's not writable. |
| bool a_writable = a->writable() || PresumedWritable(a); |
| bool b_writable = b->writable() || PresumedWritable(b); |
| if (a_writable && !b_writable) { |
| return a_is_better; |
| } |
| if (!a_writable && b_writable) { |
| return b_is_better; |
| } |
| |
| // Sort based on write-state. Better states have lower values. |
| if (a->write_state() < b->write_state()) { |
| return a_is_better; |
| } |
| if (b->write_state() < a->write_state()) { |
| return b_is_better; |
| } |
| |
| // We prefer a receiving connection to a non-receiving, higher-priority |
| // connection when sorting connections and choosing which connection to |
| // switch to. |
| if (a->receiving() && !b->receiving()) { |
| return a_is_better; |
| } |
| if (!a->receiving() && b->receiving()) { |
| if (!receiving_unchanged_threshold || |
| (a->receiving_unchanged_since() <= *receiving_unchanged_threshold && |
| b->receiving_unchanged_since() <= *receiving_unchanged_threshold)) { |
| return b_is_better; |
| } |
| *missed_receiving_unchanged_threshold = true; |
| } |
| |
| // WARNING: Some complexity here about TCP reconnecting. |
| // When a TCP connection fails because of a TCP socket disconnecting, the |
| // active side of the connection will attempt to reconnect for 5 seconds while |
| // pretending to be writable (the connection is not set to the unwritable |
| // state). On the passive side, the connection also remains writable even |
| // though it is disconnected, and a new connection is created when the active |
| // side connects. At that point, there are two TCP connections on the passive |
| // side: 1. the old, disconnected one that is pretending to be writable, and |
| // 2. the new, connected one that is maybe not yet writable. For purposes of |
| // pruning, pinging, and selecting the selected connection, we want to treat |
| // the new connection as "better" than the old one. We could add a method |
| // called something like Connection::ImReallyBadEvenThoughImWritable, but that |
| // is equivalent to the existing Connection::connected(), which we already |
| // have. So, in code throughout this file, we'll check whether the connection |
| // is connected() or not, and if it is not, treat it as "worse" than a |
| // connected one, even though it's writable. In the code below, we're doing |
| // so to make sure we treat a new writable connection as better than an old |
| // disconnected connection. |
| |
| // In the case where we reconnect TCP connections, the original best |
| // connection is disconnected without changing to WRITE_TIMEOUT. In this case, |
| // the new connection, when it becomes writable, should have higher priority. |
| if (a->write_state() == Connection::STATE_WRITABLE && |
| b->write_state() == Connection::STATE_WRITABLE) { |
| if (a->connected() && !b->connected()) { |
| return a_is_better; |
| } |
| if (!a->connected() && b->connected()) { |
| return b_is_better; |
| } |
| } |
| return 0; |
| } |
| |
| // Compares two connections based only on the candidate and network information. |
| // Returns positive if |a| is better than |b|. |
| int P2PTransportChannel::CompareConnectionCandidates( |
| const Connection* a, |
| const Connection* b) const { |
| // Prefer lower network cost. |
| uint32_t a_cost = a->ComputeNetworkCost(); |
| uint32_t b_cost = b->ComputeNetworkCost(); |
| // Smaller cost is better. |
| if (a_cost < b_cost) { |
| return a_is_better; |
| } |
| if (a_cost > b_cost) { |
| return b_is_better; |
| } |
| |
| // Compare connection priority. Lower values get sorted last. |
| if (a->priority() > b->priority()) { |
| return a_is_better; |
| } |
| if (a->priority() < b->priority()) { |
| return b_is_better; |
| } |
| |
| // If we're still tied at this point, prefer a younger generation. |
| // (Younger generation means a larger generation number). |
| return (a->remote_candidate().generation() + a->port()->generation()) - |
| (b->remote_candidate().generation() + b->port()->generation()); |
| } |
| |
| int P2PTransportChannel::CompareConnections( |
| const Connection* a, |
| const Connection* b, |
| rtc::Optional<int64_t> receiving_unchanged_threshold, |
| bool* missed_receiving_unchanged_threshold) const { |
| RTC_CHECK(a != nullptr); |
| RTC_CHECK(b != nullptr); |
| |
| // We prefer to switch to a writable and receiving connection over a |
| // non-writable or non-receiving connection, even if the latter has |
| // been nominated by the controlling side. |
| int state_cmp = CompareConnectionStates(a, b, receiving_unchanged_threshold, |
| missed_receiving_unchanged_threshold); |
| if (state_cmp != 0) { |
| return state_cmp; |
| } |
| |
| if (ice_role_ == ICEROLE_CONTROLLED) { |
| // Compare the connections based on the nomination states and the last data |
| // received time if this is on the controlled side. |
| if (a->remote_nomination() > b->remote_nomination()) { |
| return a_is_better; |
| } |
| if (a->remote_nomination() < b->remote_nomination()) { |
| return b_is_better; |
| } |
| |
| if (a->last_data_received() > b->last_data_received()) { |
| return a_is_better; |
| } |
| if (a->last_data_received() < b->last_data_received()) { |
| return b_is_better; |
| } |
| } |
| |
| // Compare the network cost and priority. |
| return CompareConnectionCandidates(a, b); |
| } |
| |
| bool P2PTransportChannel::PresumedWritable(const Connection* conn) const { |
| return (conn->write_state() == Connection::STATE_WRITE_INIT && |
| config_.presume_writable_when_fully_relayed && |
| conn->local_candidate().type() == RELAY_PORT_TYPE && |
| (conn->remote_candidate().type() == RELAY_PORT_TYPE || |
| conn->remote_candidate().type() == PRFLX_PORT_TYPE)); |
| } |
| |
| // Sort the available connections to find the best one. We also monitor |
| // the number of available connections and the current state. |
| void P2PTransportChannel::SortConnectionsAndUpdateState() { |
| ASSERT(worker_thread_ == rtc::Thread::Current()); |
| |
| // Make sure the connection states are up-to-date since this affects how they |
| // will be sorted. |
| UpdateConnectionStates(); |
| |
| // Any changes after this point will require a re-sort. |
| sort_dirty_ = false; |
| |
| // Find the best alternative connection by sorting. It is important to note |
| // that amongst equal preference, writable connections, this will choose the |
| // one whose estimated latency is lowest. So it is the only one that we |
| // need to consider switching to. |
| std::stable_sort(connections_.begin(), connections_.end(), |
| [this](const Connection* a, const Connection* b) { |
| int cmp = CompareConnections( |
| a, b, rtc::Optional<int64_t>(), nullptr); |
| if (cmp != 0) { |
| return cmp > 0; |
| } |
| // Otherwise, sort based on latency estimate. |
| return a->rtt() < b->rtt(); |
| }); |
| |
| LOG(LS_VERBOSE) << "Sorting " << connections_.size() |
| << " available connections:"; |
| for (size_t i = 0; i < connections_.size(); ++i) { |
| LOG(LS_VERBOSE) << connections_[i]->ToString(); |
| } |
| |
| Connection* top_connection = |
| (connections_.size() > 0) ? connections_[0] : nullptr; |
| |
| // If necessary, switch to the new choice. Note that |top_connection| doesn't |
| // have to be writable to become the selected connection although it will |
| // have higher priority if it is writable. |
| MaybeSwitchSelectedConnection(top_connection, "sorting"); |
| |
| // The controlled side can prune only if the selected connection has been |
| // nominated because otherwise it may prune the connection that will be |
| // selected by the controlling side. |
| // TODO(honghaiz): This is not enough to prevent a connection from being |
| // pruned too early because with aggressive nomination, the controlling side |
| // will nominate every connection until it becomes writable. |
| if (ice_role_ == ICEROLE_CONTROLLING || |
| (selected_connection_ && selected_connection_->nominated())) { |
| PruneConnections(); |
| } |
| |
| // Check if all connections are timedout. |
| bool all_connections_timedout = true; |
| for (size_t i = 0; i < connections_.size(); ++i) { |
| if (connections_[i]->write_state() != Connection::STATE_WRITE_TIMEOUT) { |
| all_connections_timedout = false; |
| break; |
| } |
| } |
| |
| // Now update the writable state of the channel with the information we have |
| // so far. |
| if (all_connections_timedout) { |
| HandleAllTimedOut(); |
| } |
| |
| // Update the state of this channel. |
| UpdateState(); |
| |
| // Also possibly start pinging. |
| // We could start pinging if: |
| // * The first connection was created. |
| // * ICE credentials were provided. |
| // * A TCP connection became connected. |
| MaybeStartPinging(); |
| } |
| |
| void P2PTransportChannel::PruneConnections() { |
| // We can prune any connection for which there is a connected, writable |
| // connection on the same network with better or equal priority. We leave |
| // those with better priority just in case they become writable later (at |
| // which point, we would prune out the current selected connection). We leave |
| // connections on other networks because they may not be using the same |
| // resources and they may represent very distinct paths over which we can |
| // switch. If the |premier| connection is not connected, we may be |
| // reconnecting a TCP connection and temporarily do not prune connections in |
| // this network. See the big comment in CompareConnectionStates. |
| |
| // Get a list of the networks that we are using. |
| std::set<rtc::Network*> networks; |
| for (const Connection* conn : connections_) { |
| networks.insert(conn->port()->Network()); |
| } |
| for (rtc::Network* network : networks) { |
| Connection* premier = GetBestConnectionOnNetwork(network); |
| // Do not prune connections if the current selected connection is weak on |
| // this network. Otherwise, it may delete connections prematurely. |
| if (!premier || premier->weak()) { |
| continue; |
| } |
| |
| for (Connection* conn : connections_) { |
| if ((conn != premier) && (conn->port()->Network() == network) && |
| (CompareConnectionCandidates(premier, conn) >= 0)) { |
| conn->Prune(); |
| } |
| } |
| } |
| } |
| |
| // Change the selected connection, and let listeners know. |
| void P2PTransportChannel::SwitchSelectedConnection(Connection* conn) { |
| // Note: if conn is NULL, the previous |selected_connection_| has been |
| // destroyed, so don't use it. |
| Connection* old_selected_connection = selected_connection_; |
| selected_connection_ = conn; |
| if (selected_connection_) { |
| ++nomination_; |
| if (old_selected_connection) { |
| LOG_J(LS_INFO, this) << "Previous selected connection: " |
| << old_selected_connection->ToString(); |
| } |
| LOG_J(LS_INFO, this) << "New selected connection: " |
| << selected_connection_->ToString(); |
| SignalRouteChange(this, selected_connection_->remote_candidate()); |
| // This is a temporary, but safe fix to webrtc issue 5705. |
| // TODO(honghaiz): Make all ENOTCONN error routed through the transport |
| // channel so that it knows whether the media channel is allowed to |
| // send; then it will only signal ready-to-send if the media channel |
| // has been disallowed to send. |
| if (selected_connection_->writable() || |
| PresumedWritable(selected_connection_)) { |
| SignalReadyToSend(this); |
| } |
| } else { |
| LOG_J(LS_INFO, this) << "No selected connection"; |
| } |
| SignalSelectedCandidatePairChanged(this, selected_connection_, |
| last_sent_packet_id_, |
| ReadyToSend(selected_connection_)); |
| } |
| |
| // Warning: UpdateState should eventually be called whenever a connection |
| // is added, deleted, or the write state of any connection changes so that the |
| // transport controller will get the up-to-date channel state. However it |
| // should not be called too often; in the case that multiple connection states |
| // change, it should be called after all the connection states have changed. For |
| // example, we call this at the end of SortConnectionsAndUpdateState. |
| void P2PTransportChannel::UpdateState() { |
| TransportChannelState state = ComputeState(); |
| if (state_ != state) { |
| LOG_J(LS_INFO, this) << "Transport channel state changed from " << state_ |
| << " to " << state; |
| // Check that the requested transition is allowed. Note that |
| // P2PTransportChannel does not (yet) implement a direct mapping of the ICE |
| // states from the standard; the difference is covered by |
| // TransportController and PeerConnection. |
| switch (state_) { |
| case STATE_INIT: |
| // TODO(deadbeef): Once we implement end-of-candidates signaling, |
| // we shouldn't go from INIT to COMPLETED. |
| RTC_DCHECK(state == STATE_CONNECTING || state == STATE_COMPLETED); |
| break; |
| case STATE_CONNECTING: |
| RTC_DCHECK(state == STATE_COMPLETED || state == STATE_FAILED); |
| break; |
| case STATE_COMPLETED: |
| // TODO(deadbeef): Once we implement end-of-candidates signaling, |
| // we shouldn't go from COMPLETED to CONNECTING. |
| // Though we *can* go from COMPlETED to FAILED, if consent expires. |
| RTC_DCHECK(state == STATE_CONNECTING || state == STATE_FAILED); |
| break; |
| case STATE_FAILED: |
| // TODO(deadbeef): Once we implement end-of-candidates signaling, |
| // we shouldn't go from FAILED to CONNECTING or COMPLETED. |
| RTC_DCHECK(state == STATE_CONNECTING || state == STATE_COMPLETED); |
| break; |
| default: |
| RTC_DCHECK(false); |
| break; |
| } |
| state_ = state; |
| SignalStateChanged(this); |
| } |
| |
| // If our selected connection is "presumed writable" (TURN-TURN with no |
| // CreatePermission required), act like we're already writable to the upper |
| // layers, so they can start media quicker. |
| bool writable = |
| selected_connection_ && (selected_connection_->writable() || |
| PresumedWritable(selected_connection_)); |
| set_writable(writable); |
| |
| bool receiving = false; |
| for (const Connection* connection : connections_) { |
| if (connection->receiving()) { |
| receiving = true; |
| break; |
| } |
| } |
| set_receiving(receiving); |
| } |
| |
| void P2PTransportChannel::MaybeStopPortAllocatorSessions() { |
| if (!IsGettingPorts()) { |
| return; |
| } |
| |
| for (const auto& session : allocator_sessions_) { |
| if (session->IsStopped()) { |
| continue; |
| } |
| // If gathering continually, keep the last session running so that |
| // it can gather candidates if the networks change. |
| if (config_.gather_continually() && session == allocator_sessions_.back()) { |
| session->ClearGettingPorts(); |
| } else { |
| session->StopGettingPorts(); |
| } |
| } |
| } |
| |
| // If all connections timed out, delete them all. |
| void P2PTransportChannel::HandleAllTimedOut() { |
| for (Connection* connection : connections_) { |
| connection->Destroy(); |
| } |
| } |
| |
| bool P2PTransportChannel::weak() const { |
| return !selected_connection_ || selected_connection_->weak(); |
| } |
| |
| bool P2PTransportChannel::ReadyToSend(Connection* connection) const { |
| // Note that we allow sending on an unreliable connection, because it's |
| // possible that it became unreliable simply due to bad chance. |
| // So this shouldn't prevent attempting to send media. |
| return connection != nullptr && |
| (connection->writable() || |
| connection->write_state() == Connection::STATE_WRITE_UNRELIABLE || |
| PresumedWritable(connection)); |
| } |
| |
| // If we have a selected connection, return it, otherwise return top one in the |
| // list (later we will mark it best). |
| Connection* P2PTransportChannel::GetBestConnectionOnNetwork( |
| rtc::Network* network) const { |
| // If the selected connection is on this network, then it wins. |
| if (selected_connection_ && |
| (selected_connection_->port()->Network() == network)) { |
| return selected_connection_; |
| } |
| |
| // Otherwise, we return the top-most in sorted order. |
| for (size_t i = 0; i < connections_.size(); ++i) { |
| if (connections_[i]->port()->Network() == network) { |
| return connections_[i]; |
| } |
| } |
| |
| return NULL; |
| } |
| |
| // Handle any queued up requests |
| void P2PTransportChannel::OnMessage(rtc::Message *pmsg) { |
| switch (pmsg->message_id) { |
| case MSG_SORT_AND_UPDATE_STATE: |
| SortConnectionsAndUpdateState(); |
| break; |
| case MSG_CHECK_AND_PING: |
| OnCheckAndPing(); |
| break; |
| case MSG_REGATHER_ON_FAILED_NETWORKS: |
| OnRegatherOnFailedNetworks(); |
| break; |
| default: |
| ASSERT(false); |
| break; |
| } |
| } |
| |
| // Handle queued up check-and-ping request |
| void P2PTransportChannel::OnCheckAndPing() { |
| // Make sure the states of the connections are up-to-date (since this affects |
| // which ones are pingable). |
| UpdateConnectionStates(); |
| // When the selected connection is not receiving or not writable, or any |
| // active connection has not been pinged enough times, use the weak ping |
| // interval. |
| bool need_more_pings_at_weak_interval = std::any_of( |
| connections_.begin(), connections_.end(), [](Connection* conn) { |
| return conn->active() && |
| conn->num_pings_sent() < MIN_PINGS_AT_WEAK_PING_INTERVAL; |
| }); |
| int ping_interval = (weak() || need_more_pings_at_weak_interval) |
| ? weak_ping_interval_ |
| : STRONG_PING_INTERVAL; |
| if (rtc::TimeMillis() >= last_ping_sent_ms_ + ping_interval) { |
| Connection* conn = FindNextPingableConnection(); |
| if (conn) { |
| PingConnection(conn); |
| MarkConnectionPinged(conn); |
| } |
| } |
| int delay = std::min(ping_interval, check_receiving_interval_); |
| thread()->PostDelayed(RTC_FROM_HERE, delay, this, MSG_CHECK_AND_PING); |
| } |
| |
| // A connection is considered a backup connection if the channel state |
| // is completed, the connection is not the selected connection and it is active. |
| bool P2PTransportChannel::IsBackupConnection(const Connection* conn) const { |
| return state_ == STATE_COMPLETED && conn != selected_connection_ && |
| conn->active(); |
| } |
| |
| // Is the connection in a state for us to even consider pinging the other side? |
| // We consider a connection pingable even if it's not connected because that's |
| // how a TCP connection is kicked into reconnecting on the active side. |
| bool P2PTransportChannel::IsPingable(const Connection* conn, |
| int64_t now) const { |
| const Candidate& remote = conn->remote_candidate(); |
| // We should never get this far with an empty remote ufrag. |
| ASSERT(!remote.username().empty()); |
| if (remote.username().empty() || remote.password().empty()) { |
| // If we don't have an ICE ufrag and pwd, there's no way we can ping. |
| return false; |
| } |
| |
| // A failed connection will not be pinged. |
| if (conn->state() == Connection::STATE_FAILED) { |
| return false; |
| } |
| |
| // An never connected connection cannot be written to at all, so pinging is |
| // out of the question. However, if it has become WRITABLE, it is in the |
| // reconnecting state so ping is needed. |
| if (!conn->connected() && !conn->writable()) { |
| return false; |
| } |
| |
| // If the channel is weakly connected, ping all connections. |
| if (weak()) { |
| return true; |
| } |
| |
| // Always ping active connections regardless whether the channel is completed |
| // or not, but backup connections are pinged at a slower rate. |
| if (IsBackupConnection(conn)) { |
| return conn->rtt_samples() == 0 || |
| (now >= conn->last_ping_response_received() + |
| config_.backup_connection_ping_interval); |
| } |
| // Don't ping inactive non-backup connections. |
| if (!conn->active()) { |
| return false; |
| } |
| |
| // Do ping unwritable, active connections. |
| if (!conn->writable()) { |
| return true; |
| } |
| |
| // Ping writable, active connections if it's been long enough since the last |
| // ping. |
| int ping_interval = CalculateActiveWritablePingInterval(conn, now); |
| return (now >= conn->last_ping_sent() + ping_interval); |
| } |
| |
| bool P2PTransportChannel::IsSelectedConnectionPingable(int64_t now) { |
| if (!selected_connection_ || !selected_connection_->connected() || |
| !selected_connection_->writable()) { |
| return false; |
| } |
| |
| int interval = CalculateActiveWritablePingInterval(selected_connection_, now); |
| return selected_connection_->last_ping_sent() + interval <= now; |
| } |
| |
| int P2PTransportChannel::CalculateActiveWritablePingInterval( |
| const Connection* conn, |
| int64_t now) const { |
| // Ping each connection at a higher rate at least |
| // MIN_PINGS_AT_WEAK_PING_INTERVAL times. |
| if (conn->num_pings_sent() < MIN_PINGS_AT_WEAK_PING_INTERVAL) { |
| return weak_ping_interval_; |
| } |
| |
| int stable_interval = config_.stable_writable_connection_ping_interval; |
| int stablizing_interval = |
| std::min(stable_interval, STABILIZING_WRITABLE_CONNECTION_PING_INTERVAL); |
| |
| return conn->stable(now) ? stable_interval : stablizing_interval; |
| } |
| |
| // Returns the next pingable connection to ping. This will be the oldest |
| // pingable connection unless we have a connected, writable connection that is |
| // past the writable ping interval. When reconnecting a TCP |
| // connection, the selected connection is disconnected, although still WRITABLE |
| // while reconnecting. The newly created connection should be selected as the |
| // ping target to become writable instead. See the big comment in |
| // CompareConnectionStates. |
| Connection* P2PTransportChannel::FindNextPingableConnection() { |
| int64_t now = rtc::TimeMillis(); |
| Connection* conn_to_ping = nullptr; |
| if (IsSelectedConnectionPingable(now)) { |
| conn_to_ping = selected_connection_; |
| } else { |
| conn_to_ping = FindConnectionToPing(now); |
| } |
| return conn_to_ping; |
| } |
| |
| void P2PTransportChannel::MarkConnectionPinged(Connection* conn) { |
| if (conn && pinged_connections_.insert(conn).second) { |
| unpinged_connections_.erase(conn); |
| } |
| } |
| |
| // Apart from sending ping from |conn| this method also updates |
| // |use_candidate_attr| and |nomination| flags. One of the flags is set to |
| // nominate |conn| if this channel is in CONTROLLING. |
| void P2PTransportChannel::PingConnection(Connection* conn) { |
| bool use_candidate_attr = false; |
| uint32_t nomination = 0; |
| if (ice_role_ == ICEROLE_CONTROLLING) { |
| bool renomination_supported = ice_parameters_.renomination && |
| !remote_ice_parameters_.empty() && |
| remote_ice_parameters_.back().renomination; |
| if (renomination_supported) { |
| nomination = GetNominationAttr(conn); |
| } else { |
| use_candidate_attr = |
| GetUseCandidateAttr(conn, config_.default_nomination_mode); |
| } |
| } |
| conn->set_nomination(nomination); |
| conn->set_use_candidate_attr(use_candidate_attr); |
| last_ping_sent_ms_ = rtc::TimeMillis(); |
| conn->Ping(last_ping_sent_ms_); |
| } |
| |
| uint32_t P2PTransportChannel::GetNominationAttr(Connection* conn) const { |
| return (conn == selected_connection_) ? nomination_ : 0; |
| } |
| |
| // Nominate a connection based on the NominationMode. |
| bool P2PTransportChannel::GetUseCandidateAttr(Connection* conn, |
| NominationMode mode) const { |
| switch (mode) { |
| case NominationMode::REGULAR: |
| // TODO(honghaiz): Implement regular nomination. |
| return false; |
| case NominationMode::AGGRESSIVE: |
| if (remote_ice_mode_ == ICEMODE_LITE) { |
| return GetUseCandidateAttr(conn, NominationMode::REGULAR); |
| } |
| return true; |
| case NominationMode::SEMI_AGGRESSIVE: { |
| // Nominate if |
| // a) Remote is in FULL ICE AND |
| // a.1) |conn| is the selected connection OR |
| // a.2) there is no selected connection OR |
| // a.3) the selected connection is unwritable OR |
| // a.4) |conn| has higher priority than selected_connection. |
| // b) Remote is in LITE ICE AND |
| // b.1) |conn| is the selected_connection AND |
| // b.2) |conn| is writable. |
| bool selected = conn == selected_connection_; |
| if (remote_ice_mode_ == ICEMODE_LITE) { |
| return selected && conn->writable(); |
| } |
| bool better_than_selected = |
| !selected_connection_ || !selected_connection_->writable() || |
| CompareConnectionCandidates(selected_connection_, conn) < 0; |
| return selected || better_than_selected; |
| } |
| default: |
| RTC_DCHECK(false); |
| return false; |
| } |
| } |
| |
| // When a connection's state changes, we need to figure out who to use as |
| // the selected connection again. It could have become usable, or become |
| // unusable. |
| void P2PTransportChannel::OnConnectionStateChange(Connection* connection) { |
| ASSERT(worker_thread_ == rtc::Thread::Current()); |
| |
| // May stop the allocator session when at least one connection becomes |
| // strongly connected after starting to get ports and the local candidate of |
| // the connection is at the latest generation. It is not enough to check |
| // that the connection becomes weakly connected because the connection may be |
| // changing from (writable, receiving) to (writable, not receiving). |
| bool strongly_connected = !connection->weak(); |
| bool latest_generation = connection->local_candidate().generation() >= |
| allocator_session()->generation(); |
| if (strongly_connected && latest_generation) { |
| MaybeStopPortAllocatorSessions(); |
| } |
| |
| // We have to unroll the stack before doing this because we may be changing |
| // the state of connections while sorting. |
| RequestSortAndStateUpdate(); |
| } |
| |
| // When a connection is removed, edit it out, and then update our best |
| // connection. |
| void P2PTransportChannel::OnConnectionDestroyed(Connection* connection) { |
| ASSERT(worker_thread_ == rtc::Thread::Current()); |
| |
| // Note: the previous selected_connection_ may be destroyed by now, so don't |
| // use it. |
| |
| // Remove this connection from the list. |
| std::vector<Connection*>::iterator iter = |
| std::find(connections_.begin(), connections_.end(), connection); |
| ASSERT(iter != connections_.end()); |
| pinged_connections_.erase(*iter); |
| unpinged_connections_.erase(*iter); |
| connections_.erase(iter); |
| |
| LOG_J(LS_INFO, this) << "Removed connection (" |
| << static_cast<int>(connections_.size()) << " remaining)"; |
| |
| // If this is currently the selected connection, then we need to pick a new |
| // one. The call to SortConnectionsAndUpdateState will pick a new one. It |
| // looks at the current selected connection in order to avoid switching |
| // between fairly similar ones. Since this connection is no longer an option, |
| // we can just set selected to nullptr and re-choose a best assuming that |
| // there was no selected connection. |
| if (selected_connection_ == connection) { |
| LOG(LS_INFO) << "Selected connection destroyed. Will choose a new one."; |
| SwitchSelectedConnection(nullptr); |
| RequestSortAndStateUpdate(); |
| } else { |
| // If a non-selected connection was destroyed, we don't need to re-sort but |
| // we do need to update state, because we could be switching to "failed" or |
| // "completed". |
| UpdateState(); |
| } |
| } |
| |
| // When a port is destroyed, remove it from our list of ports to use for |
| // connection attempts. |
| void P2PTransportChannel::OnPortDestroyed(PortInterface* port) { |
| ASSERT(worker_thread_ == rtc::Thread::Current()); |
| |
| ports_.erase(std::remove(ports_.begin(), ports_.end(), port), ports_.end()); |
| pruned_ports_.erase( |
| std::remove(pruned_ports_.begin(), pruned_ports_.end(), port), |
| pruned_ports_.end()); |
| LOG(INFO) << "Removed port because it is destroyed: " << ports_.size() |
| << " remaining"; |
| } |
| |
| void P2PTransportChannel::OnPortsPruned( |
| PortAllocatorSession* session, |
| const std::vector<PortInterface*>& ports) { |
| ASSERT(worker_thread_ == rtc::Thread::Current()); |
| for (PortInterface* port : ports) { |
| if (PrunePort(port)) { |
| LOG(INFO) << "Removed port: " << port->ToString() << " " << ports_.size() |
| << " remaining"; |
| } |
| } |
| } |
| |
| void P2PTransportChannel::OnCandidatesRemoved( |
| PortAllocatorSession* session, |
| const std::vector<Candidate>& candidates) { |
| ASSERT(worker_thread_ == rtc::Thread::Current()); |
| // Do not signal candidate removals if continual gathering is not enabled, or |
| // if this is not the last session because an ICE restart would have signaled |
| // the remote side to remove all candidates in previous sessions. |
| if (!config_.gather_continually() || session != allocator_session()) { |
| return; |
| } |
| |
| std::vector<Candidate> candidates_to_remove; |
| for (Candidate candidate : candidates) { |
| candidate.set_transport_name(transport_name()); |
| candidates_to_remove.push_back(candidate); |
| } |
| SignalCandidatesRemoved(this, candidates_to_remove); |
| } |
| |
| void P2PTransportChannel::OnRegatherOnFailedNetworks() { |
| // Only re-gather when the current session is in the CLEARED state (i.e., not |
| // running or stopped). It is only possible to enter this state when we gather |
| // continually, so there is an implicit check on continual gathering here. |
| if (!allocator_sessions_.empty() && allocator_session()->IsCleared()) { |
| allocator_session()->RegatherOnFailedNetworks(); |
| } |
| |
| thread()->PostDelayed(RTC_FROM_HERE, |
| *config_.regather_on_failed_networks_interval, this, |
| MSG_REGATHER_ON_FAILED_NETWORKS); |
| } |
| |
| void P2PTransportChannel::PruneAllPorts() { |
| pruned_ports_.insert(pruned_ports_.end(), ports_.begin(), ports_.end()); |
| ports_.clear(); |
| } |
| |
| bool P2PTransportChannel::PrunePort(PortInterface* port) { |
| auto it = std::find(ports_.begin(), ports_.end(), port); |
| // Don't need to do anything if the port has been deleted from the port list. |
| if (it == ports_.end()) { |
| return false; |
| } |
| ports_.erase(it); |
| pruned_ports_.push_back(port); |
| return true; |
| } |
| |
| // We data is available, let listeners know |
| void P2PTransportChannel::OnReadPacket(Connection* connection, |
| const char* data, |
| size_t len, |
| const rtc::PacketTime& packet_time) { |
| ASSERT(worker_thread_ == rtc::Thread::Current()); |
| |
| // Do not deliver, if packet doesn't belong to the correct transport channel. |
| if (!FindConnection(connection)) |
| return; |
| |
| // Let the client know of an incoming packet |
| SignalReadPacket(this, data, len, packet_time, 0); |
| |
| // May need to switch the sending connection based on the receiving media path |
| // if this is the controlled side. |
| if (ice_role_ == ICEROLE_CONTROLLED) { |
| MaybeSwitchSelectedConnection(connection, "data received"); |
| } |
| } |
| |
| void P2PTransportChannel::OnSentPacket(const rtc::SentPacket& sent_packet) { |
| ASSERT(worker_thread_ == rtc::Thread::Current()); |
| |
| SignalSentPacket(this, sent_packet); |
| } |
| |
| void P2PTransportChannel::OnReadyToSend(Connection* connection) { |
| if (connection == selected_connection_ && writable()) { |
| SignalReadyToSend(this); |
| } |
| } |
| |
| // Find "triggered checks". We ping first those connections that have |
| // received a ping but have not sent a ping since receiving it |
| // (last_received_ping > last_sent_ping). But we shouldn't do |
| // triggered checks if the connection is already writable. |
| Connection* P2PTransportChannel::FindOldestConnectionNeedingTriggeredCheck( |
| int64_t now) { |
| Connection* oldest_needing_triggered_check = nullptr; |
| for (auto conn : connections_) { |
| if (!IsPingable(conn, now)) { |
| continue; |
| } |
| bool needs_triggered_check = |
| (!conn->writable() && |
| conn->last_ping_received() > conn->last_ping_sent()); |
| if (needs_triggered_check && |
| (!oldest_needing_triggered_check || |
| (conn->last_ping_received() < |
| oldest_needing_triggered_check->last_ping_received()))) { |
| oldest_needing_triggered_check = conn; |
| } |
| } |
| |
| if (oldest_needing_triggered_check) { |
| LOG(LS_INFO) << "Selecting connection for triggered check: " |
| << oldest_needing_triggered_check->ToString(); |
| } |
| return oldest_needing_triggered_check; |
| } |
| |
| Connection* P2PTransportChannel::FindConnectionToPing(int64_t now) { |
| RTC_CHECK(connections_.size() == |
| pinged_connections_.size() + unpinged_connections_.size()); |
| |
| // If there is nothing pingable in the |unpinged_connections_|, copy |
| // over from |pinged_connections_|. We do this here such that the |
| // new connection will take precedence. |
| if (std::find_if(unpinged_connections_.begin(), unpinged_connections_.end(), |
| [this, now](Connection* conn) { |
| return this->IsPingable(conn, now); |
| }) == unpinged_connections_.end()) { |
| unpinged_connections_.insert(pinged_connections_.begin(), |
| pinged_connections_.end()); |
| pinged_connections_.clear(); |
| } |
| |
| Connection* conn_to_ping = FindOldestConnectionNeedingTriggeredCheck(now); |
| if (conn_to_ping) { |
| return conn_to_ping; |
| } |
| |
| for (Connection* conn : unpinged_connections_) { |
| if (!IsPingable(conn, now)) { |
| continue; |
| } |
| if (!conn_to_ping || |
| SelectMostPingableConnection(conn_to_ping, conn) == conn) { |
| conn_to_ping = conn; |
| } |
| } |
| return conn_to_ping; |
| } |
| |
| Connection* P2PTransportChannel::MostLikelyToWork(Connection* conn1, |
| Connection* conn2) { |
| bool rr1 = IsRelayRelay(conn1); |
| bool rr2 = IsRelayRelay(conn2); |
| if (rr1 && !rr2) { |
| return conn1; |
| } else if (rr2 && !rr1) { |
| return conn2; |
| } else if (rr1 && rr2) { |
| bool udp1 = IsUdp(conn1); |
| bool udp2 = IsUdp(conn2); |
| if (udp1 && !udp2) { |
| return conn1; |
| } else if (udp2 && udp1) { |
| return conn2; |
| } |
| } |
| return nullptr; |
| } |
| |
| Connection* P2PTransportChannel::LeastRecentlyPinged(Connection* conn1, |
| Connection* conn2) { |
| if (conn1->last_ping_sent() < conn2->last_ping_sent()) { |
| return conn1; |
| } |
| if (conn1->last_ping_sent() > conn2->last_ping_sent()) { |
| return conn2; |
| } |
| return nullptr; |
| } |
| |
| Connection* P2PTransportChannel::SelectMostPingableConnection( |
| Connection* conn1, |
| Connection* conn2) { |
| RTC_DCHECK(conn1 != conn2); |
| if (config_.prioritize_most_likely_candidate_pairs) { |
| Connection* most_likely_to_work_conn = MostLikelyToWork(conn1, conn2); |
| if (most_likely_to_work_conn) { |
| return most_likely_to_work_conn; |
| } |
| } |
| |
| Connection* least_recently_pinged_conn = LeastRecentlyPinged(conn1, conn2); |
| if (least_recently_pinged_conn) { |
| return least_recently_pinged_conn; |
| } |
| |
| // During the initial state when nothing has been pinged yet, return the first |
| // one in the ordered |connections_|. |
| return *(std::find_if(connections_.begin(), connections_.end(), |
| [conn1, conn2](Connection* conn) { |
| return conn == conn1 || conn == conn2; |
| })); |
| } |
| |
| } // namespace cricket |