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webrtc / src / b2b58d84e329e5c8de07ec51d18f854fc2318b4f / . / p2p / base / connection.cc
blob: fbbd85344b9fc093d638d695981cf54f17c22ef3 [file] [log] [blame]
/*
* Copyright 2019 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 "p2p/base/connection.h"
#include <math.h>
#include <algorithm>
#include <memory>
#include <utility>
#include <vector>
#include "absl/algorithm/container.h"
#include "absl/strings/match.h"
#include "p2p/base/port_allocator.h"
#include "rtc_base/checks.h"
#include "rtc_base/crc32.h"
#include "rtc_base/helpers.h"
#include "rtc_base/logging.h"
#include "rtc_base/mdns_responder_interface.h"
#include "rtc_base/message_digest.h"
#include "rtc_base/network.h"
#include "rtc_base/numerics/safe_minmax.h"
#include "rtc_base/string_encode.h"
#include "rtc_base/string_utils.h"
#include "rtc_base/third_party/base64/base64.h"
#include "system_wrappers/include/field_trial.h"
namespace {
// Determines whether we have seen at least the given maximum number of
// pings fail to have a response.
inline bool TooManyFailures(
const std::vector<cricket::Connection::SentPing>& pings_since_last_response,
uint32_t maximum_failures,
int rtt_estimate,
int64_t now) {
// If we haven't sent that many pings, then we can't have failed that many.
if (pings_since_last_response.size() < maximum_failures)
return false;
// Check if the window in which we would expect a response to the ping has
// already elapsed.
int64_t expected_response_time =
pings_since_last_response[maximum_failures - 1].sent_time + rtt_estimate;
return now > expected_response_time;
}
// Determines whether we have gone too long without seeing any response.
inline bool TooLongWithoutResponse(
const std::vector<cricket::Connection::SentPing>& pings_since_last_response,
int64_t maximum_time,
int64_t now) {
if (pings_since_last_response.size() == 0)
return false;
auto first = pings_since_last_response[0];
return now > (first.sent_time + maximum_time);
}
// Helper methods for converting string values of log description fields to
// enum.
webrtc::IceCandidateType GetCandidateTypeByString(const std::string& type) {
if (type == cricket::LOCAL_PORT_TYPE) {
return webrtc::IceCandidateType::kLocal;
} else if (type == cricket::STUN_PORT_TYPE) {
return webrtc::IceCandidateType::kStun;
} else if (type == cricket::PRFLX_PORT_TYPE) {
return webrtc::IceCandidateType::kPrflx;
} else if (type == cricket::RELAY_PORT_TYPE) {
return webrtc::IceCandidateType::kRelay;
}
return webrtc::IceCandidateType::kUnknown;
}
webrtc::IceCandidatePairProtocol GetProtocolByString(
const std::string& protocol) {
if (protocol == cricket::UDP_PROTOCOL_NAME) {
return webrtc::IceCandidatePairProtocol::kUdp;
} else if (protocol == cricket::TCP_PROTOCOL_NAME) {
return webrtc::IceCandidatePairProtocol::kTcp;
} else if (protocol == cricket::SSLTCP_PROTOCOL_NAME) {
return webrtc::IceCandidatePairProtocol::kSsltcp;
} else if (protocol == cricket::TLS_PROTOCOL_NAME) {
return webrtc::IceCandidatePairProtocol::kTls;
}
return webrtc::IceCandidatePairProtocol::kUnknown;
}
webrtc::IceCandidatePairAddressFamily GetAddressFamilyByInt(
int address_family) {
if (address_family == AF_INET) {
return webrtc::IceCandidatePairAddressFamily::kIpv4;
} else if (address_family == AF_INET6) {
return webrtc::IceCandidatePairAddressFamily::kIpv6;
}
return webrtc::IceCandidatePairAddressFamily::kUnknown;
}
webrtc::IceCandidateNetworkType ConvertNetworkType(rtc::AdapterType type) {
if (type == rtc::ADAPTER_TYPE_ETHERNET) {
return webrtc::IceCandidateNetworkType::kEthernet;
} else if (type == rtc::ADAPTER_TYPE_LOOPBACK) {
return webrtc::IceCandidateNetworkType::kLoopback;
} else if (type == rtc::ADAPTER_TYPE_WIFI) {
return webrtc::IceCandidateNetworkType::kWifi;
} else if (type == rtc::ADAPTER_TYPE_VPN) {
return webrtc::IceCandidateNetworkType::kVpn;
} else if (type == rtc::ADAPTER_TYPE_CELLULAR) {
return webrtc::IceCandidateNetworkType::kCellular;
}
return webrtc::IceCandidateNetworkType::kUnknown;
}
// When we don't have any RTT data, we have to pick something reasonable. We
// use a large value just in case the connection is really slow.
const int DEFAULT_RTT = 3000; // 3 seconds
// We will restrict RTT estimates (when used for determining state) to be
// within a reasonable range.
const int MINIMUM_RTT = 100; // 0.1 seconds
const int MAXIMUM_RTT = 60000; // 60 seconds
const int DEFAULT_RTT_ESTIMATE_HALF_TIME_MS = 500;
// Computes our estimate of the RTT given the current estimate.
inline int ConservativeRTTEstimate(int rtt) {
return rtc::SafeClamp(2 * rtt, MINIMUM_RTT, MAXIMUM_RTT);
}
// Weighting of the old rtt value to new data.
const int RTT_RATIO = 3; // 3 : 1
constexpr int64_t kMinExtraPingDelayMs = 100;
// Default field trials.
const cricket::IceFieldTrials kDefaultFieldTrials;
} // namespace
namespace cricket {
// A ConnectionRequest is a simple STUN ping used to determine writability.
ConnectionRequest::ConnectionRequest(Connection* connection)
: StunRequest(new IceMessage()), connection_(connection) {}
void ConnectionRequest::Prepare(StunMessage* request) {
request->SetType(STUN_BINDING_REQUEST);
std::string username;
connection_->port()->CreateStunUsername(
connection_->remote_candidate().username(), &username);
// Note that the order of attributes does not impact the parsing on the
// receiver side. The attribute is retrieved then by iterating and matching
// over all parsed attributes. See StunMessage::GetAttribute.
request->AddAttribute(
std::make_unique<StunByteStringAttribute>(STUN_ATTR_USERNAME, username));
// connection_ already holds this ping, so subtract one from count.
if (connection_->port()->send_retransmit_count_attribute()) {
request->AddAttribute(std::make_unique<StunUInt32Attribute>(
STUN_ATTR_RETRANSMIT_COUNT,
static_cast<uint32_t>(connection_->pings_since_last_response_.size() -
1)));
}
uint32_t network_info = connection_->port()->Network()->id();
network_info = (network_info << 16) | connection_->port()->network_cost();
request->AddAttribute(std::make_unique<StunUInt32Attribute>(
STUN_ATTR_NETWORK_INFO, network_info));
if (webrtc::field_trial::IsEnabled(
"WebRTC-PiggybackIceCheckAcknowledgement") &&
connection_->last_ping_id_received()) {
request->AddAttribute(std::make_unique<StunByteStringAttribute>(
STUN_ATTR_LAST_ICE_CHECK_RECEIVED,
connection_->last_ping_id_received().value()));
}
// Adding ICE_CONTROLLED or ICE_CONTROLLING attribute based on the role.
if (connection_->port()->GetIceRole() == ICEROLE_CONTROLLING) {
request->AddAttribute(std::make_unique<StunUInt64Attribute>(
STUN_ATTR_ICE_CONTROLLING, connection_->port()->IceTiebreaker()));
// We should have either USE_CANDIDATE attribute or ICE_NOMINATION
// attribute but not both. That was enforced in p2ptransportchannel.
if (connection_->use_candidate_attr()) {
request->AddAttribute(
std::make_unique<StunByteStringAttribute>(STUN_ATTR_USE_CANDIDATE));
}
if (connection_->nomination() &&
connection_->nomination() != connection_->acked_nomination()) {
request->AddAttribute(std::make_unique<StunUInt32Attribute>(
STUN_ATTR_NOMINATION, connection_->nomination()));
}
} else if (connection_->port()->GetIceRole() == ICEROLE_CONTROLLED) {
request->AddAttribute(std::make_unique<StunUInt64Attribute>(
STUN_ATTR_ICE_CONTROLLED, connection_->port()->IceTiebreaker()));
} else {
RTC_NOTREACHED();
}
// Adding PRIORITY Attribute.
// Changing the type preference to Peer Reflexive and local preference
// and component id information is unchanged from the original priority.
// priority = (2^24)*(type preference) +
// (2^8)*(local preference) +
// (2^0)*(256 - component ID)
uint32_t type_preference =
(connection_->local_candidate().protocol() == TCP_PROTOCOL_NAME)
? ICE_TYPE_PREFERENCE_PRFLX_TCP
: ICE_TYPE_PREFERENCE_PRFLX;
uint32_t prflx_priority =
type_preference << 24 |
(connection_->local_candidate().priority() & 0x00FFFFFF);
request->AddAttribute(std::make_unique<StunUInt32Attribute>(
STUN_ATTR_PRIORITY, prflx_priority));
// Adding Message Integrity attribute.
request->AddMessageIntegrity(connection_->remote_candidate().password());
// Adding Fingerprint.
request->AddFingerprint();
}
void ConnectionRequest::OnResponse(StunMessage* response) {
connection_->OnConnectionRequestResponse(this, response);
}
void ConnectionRequest::OnErrorResponse(StunMessage* response) {
connection_->OnConnectionRequestErrorResponse(this, response);
}
void ConnectionRequest::OnTimeout() {
connection_->OnConnectionRequestTimeout(this);
}
void ConnectionRequest::OnSent() {
connection_->OnConnectionRequestSent(this);
// Each request is sent only once. After a single delay , the request will
// time out.
timeout_ = true;
}
int ConnectionRequest::resend_delay() {
return CONNECTION_RESPONSE_TIMEOUT;
}
Connection::Connection(Port* port,
size_t index,
const Candidate& remote_candidate)
: id_(rtc::CreateRandomId()),
port_(port),
local_candidate_index_(index),
remote_candidate_(remote_candidate),
recv_rate_tracker_(100, 10u),
send_rate_tracker_(100, 10u),
write_state_(STATE_WRITE_INIT),
receiving_(false),
connected_(true),
pruned_(false),
use_candidate_attr_(false),
remote_ice_mode_(ICEMODE_FULL),
requests_(port->thread()),
rtt_(DEFAULT_RTT),
last_ping_sent_(0),
last_ping_received_(0),
last_data_received_(0),
last_ping_response_received_(0),
reported_(false),
state_(IceCandidatePairState::WAITING),
time_created_ms_(rtc::TimeMillis()),
field_trials_(&kDefaultFieldTrials),
rtt_estimate_(DEFAULT_RTT_ESTIMATE_HALF_TIME_MS) {
// All of our connections start in WAITING state.
// TODO(mallinath) - Start connections from STATE_FROZEN.
// Wire up to send stun packets
requests_.SignalSendPacket.connect(this, &Connection::OnSendStunPacket);
RTC_LOG(LS_INFO) << ToString() << ": Connection created";
}
Connection::~Connection() {}
const Candidate& Connection::local_candidate() const {
RTC_DCHECK(local_candidate_index_ < port_->Candidates().size());
return port_->Candidates()[local_candidate_index_];
}
const Candidate& Connection::remote_candidate() const {
return remote_candidate_;
}
const rtc::Network* Connection::network() const {
return port()->Network();
}
int Connection::generation() const {
return port()->generation();
}
uint64_t Connection::priority() const {
uint64_t priority = 0;
// RFC 5245 - 5.7.2. Computing Pair Priority and Ordering Pairs
// Let G be the priority for the candidate provided by the controlling
// agent. Let D be the priority for the candidate provided by the
// controlled agent.
// pair priority = 2^32*MIN(G,D) + 2*MAX(G,D) + (G>D?1:0)
IceRole role = port_->GetIceRole();
if (role != ICEROLE_UNKNOWN) {
uint32_t g = 0;
uint32_t d = 0;
if (role == ICEROLE_CONTROLLING) {
g = local_candidate().priority();
d = remote_candidate_.priority();
} else {
g = remote_candidate_.priority();
d = local_candidate().priority();
}
priority = std::min(g, d);
priority = priority << 32;
priority += 2 * std::max(g, d) + (g > d ? 1 : 0);
}
return priority;
}
void Connection::set_write_state(WriteState value) {
WriteState old_value = write_state_;
write_state_ = value;
if (value != old_value) {
RTC_LOG(LS_VERBOSE) << ToString() << ": set_write_state from: " << old_value
<< " to " << value;
SignalStateChange(this);
}
}
void Connection::UpdateReceiving(int64_t now) {
bool receiving;
if (last_ping_sent() < last_ping_response_received()) {
// We consider any candidate pair that has its last connectivity check
// acknowledged by a response as receiving, particularly for backup
// candidate pairs that send checks at a much slower pace than the selected
// one. Otherwise, a backup candidate pair constantly becomes not receiving
// as a side effect of a long ping interval, since we do not have a separate
// receiving timeout for backup candidate pairs. See
// IceConfig.ice_backup_candidate_pair_ping_interval,
// IceConfig.ice_connection_receiving_timeout and their default value.
receiving = true;
} else {
receiving =
last_received() > 0 && now <= last_received() + receiving_timeout();
}
if (receiving_ == receiving) {
return;
}
RTC_LOG(LS_VERBOSE) << ToString() << ": set_receiving to " << receiving;
receiving_ = receiving;
receiving_unchanged_since_ = now;
SignalStateChange(this);
}
void Connection::set_state(IceCandidatePairState state) {
IceCandidatePairState old_state = state_;
state_ = state;
if (state != old_state) {
RTC_LOG(LS_VERBOSE) << ToString() << ": set_state";
}
}
void Connection::set_connected(bool value) {
bool old_value = connected_;
connected_ = value;
if (value != old_value) {
RTC_LOG(LS_VERBOSE) << ToString() << ": Change connected_ to " << value;
SignalStateChange(this);
}
}
void Connection::set_use_candidate_attr(bool enable) {
use_candidate_attr_ = enable;
}
int Connection::unwritable_timeout() const {
return unwritable_timeout_.value_or(CONNECTION_WRITE_CONNECT_TIMEOUT);
}
int Connection::unwritable_min_checks() const {
return unwritable_min_checks_.value_or(CONNECTION_WRITE_CONNECT_FAILURES);
}
int Connection::inactive_timeout() const {
return inactive_timeout_.value_or(CONNECTION_WRITE_TIMEOUT);
}
int Connection::receiving_timeout() const {
return receiving_timeout_.value_or(WEAK_CONNECTION_RECEIVE_TIMEOUT);
}
void Connection::SetIceFieldTrials(const IceFieldTrials* field_trials) {
field_trials_ = field_trials;
rtt_estimate_.SetHalfTime(field_trials->rtt_estimate_halftime_ms);
}
void Connection::OnSendStunPacket(const void* data,
size_t size,
StunRequest* req) {
rtc::PacketOptions options(port_->StunDscpValue());
options.info_signaled_after_sent.packet_type =
rtc::PacketType::kIceConnectivityCheck;
auto err =
port_->SendTo(data, size, remote_candidate_.address(), options, false);
if (err < 0) {
RTC_LOG(LS_WARNING) << ToString()
<< ": Failed to send STUN ping "
" err="
<< err << " id=" << rtc::hex_encode(req->id());
}
}
void Connection::OnReadPacket(const char* data,
size_t size,
int64_t packet_time_us) {
std::unique_ptr<IceMessage> msg;
std::string remote_ufrag;
const rtc::SocketAddress& addr(remote_candidate_.address());
if (!port_->GetStunMessage(data, size, addr, &msg, &remote_ufrag)) {
// The packet did not parse as a valid STUN message
// This is a data packet, pass it along.
last_data_received_ = rtc::TimeMillis();
UpdateReceiving(last_data_received_);
recv_rate_tracker_.AddSamples(size);
SignalReadPacket(this, data, size, packet_time_us);
// If timed out sending writability checks, start up again
if (!pruned_ && (write_state_ == STATE_WRITE_TIMEOUT)) {
RTC_LOG(LS_WARNING)
<< "Received a data packet on a timed-out Connection. "
"Resetting state to STATE_WRITE_INIT.";
set_write_state(STATE_WRITE_INIT);
}
} else if (!msg) {
// The packet was STUN, but failed a check and was handled internally.
} else {
// The packet is STUN and passed the Port checks.
// Perform our own checks to ensure this packet is valid.
// If this is a STUN request, then update the receiving bit and respond.
// If this is a STUN response, then update the writable bit.
// Log at LS_INFO if we receive a ping on an unwritable connection.
rtc::LoggingSeverity sev = (!writable() ? rtc::LS_INFO : rtc::LS_VERBOSE);
switch (msg->type()) {
case STUN_BINDING_REQUEST:
RTC_LOG_V(sev) << ToString() << ": Received STUN ping, id="
<< rtc::hex_encode(msg->transaction_id());
if (remote_ufrag == remote_candidate_.username()) {
HandleBindingRequest(msg.get());
} else {
// The packet had the right local username, but the remote username
// was not the right one for the remote address.
RTC_LOG(LS_ERROR)
<< ToString()
<< ": Received STUN request with bad remote username "
<< remote_ufrag;
port_->SendBindingErrorResponse(msg.get(), addr,
STUN_ERROR_UNAUTHORIZED,
STUN_ERROR_REASON_UNAUTHORIZED);
}
break;
// Response from remote peer. Does it match request sent?
// This doesn't just check, it makes callbacks if transaction
// id's match.
case STUN_BINDING_RESPONSE:
case STUN_BINDING_ERROR_RESPONSE:
if (msg->ValidateMessageIntegrity(data, size,
remote_candidate().password())) {
requests_.CheckResponse(msg.get());
}
// Otherwise silently discard the response message.
break;
// Remote end point sent an STUN indication instead of regular binding
// request. In this case |last_ping_received_| will be updated but no
// response will be sent.
case STUN_BINDING_INDICATION:
ReceivedPing(msg->transaction_id());
break;
default:
RTC_NOTREACHED();
break;
}
}
}
void Connection::HandleBindingRequest(IceMessage* msg) {
// This connection should now be receiving.
ReceivedPing(msg->transaction_id());
if (webrtc::field_trial::IsEnabled("WebRTC-ExtraICEPing") &&
last_ping_response_received_ == 0) {
if (local_candidate().type() == RELAY_PORT_TYPE ||
local_candidate().type() == PRFLX_PORT_TYPE ||
remote_candidate().type() == RELAY_PORT_TYPE ||
remote_candidate().type() == PRFLX_PORT_TYPE) {
const int64_t now = rtc::TimeMillis();
if (last_ping_sent_ + kMinExtraPingDelayMs <= now) {
RTC_LOG(LS_INFO) << ToString()
<< "WebRTC-ExtraICEPing/Sending extra ping"
<< " last_ping_sent_: " << last_ping_sent_
<< " now: " << now
<< " (diff: " << (now - last_ping_sent_) << ")";
Ping(now);
} else {
RTC_LOG(LS_INFO) << ToString()
<< "WebRTC-ExtraICEPing/Not sending extra ping"
<< " last_ping_sent_: " << last_ping_sent_
<< " now: " << now
<< " (diff: " << (now - last_ping_sent_) << ")";
}
}
}
const rtc::SocketAddress& remote_addr = remote_candidate_.address();
const std::string& remote_ufrag = remote_candidate_.username();
// Check for role conflicts.
if (!port_->MaybeIceRoleConflict(remote_addr, msg, remote_ufrag)) {
// Received conflicting role from the peer.
RTC_LOG(LS_INFO) << "Received conflicting role from the peer.";
return;
}
stats_.recv_ping_requests++;
LogCandidatePairEvent(webrtc::IceCandidatePairEventType::kCheckReceived,
msg->reduced_transaction_id());
// This is a validated stun request from remote peer.
SendBindingResponse(msg);
// If it timed out on writing check, start up again
if (!pruned_ && write_state_ == STATE_WRITE_TIMEOUT) {
set_write_state(STATE_WRITE_INIT);
}
if (port_->GetIceRole() == ICEROLE_CONTROLLED) {
const StunUInt32Attribute* nomination_attr =
msg->GetUInt32(STUN_ATTR_NOMINATION);
uint32_t nomination = 0;
if (nomination_attr) {
nomination = nomination_attr->value();
if (nomination == 0) {
RTC_LOG(LS_ERROR) << "Invalid nomination: " << nomination;
}
} else {
const StunByteStringAttribute* use_candidate_attr =
msg->GetByteString(STUN_ATTR_USE_CANDIDATE);
if (use_candidate_attr) {
nomination = 1;
}
}
// We don't un-nominate a connection, so we only keep a larger nomination.
if (nomination > remote_nomination_) {
set_remote_nomination(nomination);
SignalNominated(this);
}
}
// Set the remote cost if the network_info attribute is available.
// Note: If packets are re-ordered, we may get incorrect network cost
// temporarily, but it should get the correct value shortly after that.
const StunUInt32Attribute* network_attr =
msg->GetUInt32(STUN_ATTR_NETWORK_INFO);
if (network_attr) {
uint32_t network_info = network_attr->value();
uint16_t network_cost = static_cast<uint16_t>(network_info);
if (network_cost != remote_candidate_.network_cost()) {
remote_candidate_.set_network_cost(network_cost);
// Network cost change will affect the connection ranking, so signal
// state change to force a re-sort in P2PTransportChannel.
SignalStateChange(this);
}
}
if (webrtc::field_trial::IsEnabled(
"WebRTC-PiggybackIceCheckAcknowledgement")) {
HandlePiggybackCheckAcknowledgementIfAny(msg);
}
}
void Connection::SendBindingResponse(const StunMessage* request) {
RTC_DCHECK(request->type() == STUN_BINDING_REQUEST);
// Where I send the response.
const rtc::SocketAddress& addr = remote_candidate_.address();
// Retrieve the username from the request.
const StunByteStringAttribute* username_attr =
request->GetByteString(STUN_ATTR_USERNAME);
RTC_DCHECK(username_attr != NULL);
if (username_attr == NULL) {
// No valid username, skip the response.
return;
}
// Fill in the response message.
StunMessage response;
response.SetType(STUN_BINDING_RESPONSE);
response.SetTransactionID(request->transaction_id());
const StunUInt32Attribute* retransmit_attr =
request->GetUInt32(STUN_ATTR_RETRANSMIT_COUNT);
if (retransmit_attr) {
// Inherit the incoming retransmit value in the response so the other side
// can see our view of lost pings.
response.AddAttribute(std::make_unique<StunUInt32Attribute>(
STUN_ATTR_RETRANSMIT_COUNT, retransmit_attr->value()));
if (retransmit_attr->value() > CONNECTION_WRITE_CONNECT_FAILURES) {
RTC_LOG(LS_INFO)
<< ToString()
<< ": Received a remote ping with high retransmit count: "
<< retransmit_attr->value();
}
}
response.AddAttribute(std::make_unique<StunXorAddressAttribute>(
STUN_ATTR_XOR_MAPPED_ADDRESS, addr));
response.AddMessageIntegrity(local_candidate().password());
response.AddFingerprint();
// Send the response message.
rtc::ByteBufferWriter buf;
response.Write(&buf);
rtc::PacketOptions options(port_->StunDscpValue());
options.info_signaled_after_sent.packet_type =
rtc::PacketType::kIceConnectivityCheckResponse;
auto err = port_->SendTo(buf.Data(), buf.Length(), addr, options, false);
if (err < 0) {
RTC_LOG(LS_ERROR) << ToString()
<< ": Failed to send STUN ping response, to="
<< addr.ToSensitiveString() << ", err=" << err
<< ", id=" << rtc::hex_encode(response.transaction_id());
} else {
// Log at LS_INFO if we send a stun ping response on an unwritable
// connection.
rtc::LoggingSeverity sev = (!writable()) ? rtc::LS_INFO : rtc::LS_VERBOSE;
RTC_LOG_V(sev) << ToString() << ": Sent STUN ping response, to="
<< addr.ToSensitiveString()
<< ", id=" << rtc::hex_encode(response.transaction_id());
stats_.sent_ping_responses++;
LogCandidatePairEvent(webrtc::IceCandidatePairEventType::kCheckResponseSent,
request->reduced_transaction_id());
}
}
void Connection::OnReadyToSend() {
SignalReadyToSend(this);
}
void Connection::Prune() {
if (!pruned_ || active()) {
RTC_LOG(LS_INFO) << ToString() << ": Connection pruned";
pruned_ = true;
requests_.Clear();
set_write_state(STATE_WRITE_TIMEOUT);
}
}
void Connection::Destroy() {
// TODO(deadbeef, nisse): This may leak if an application closes a
// PeerConnection and then quickly destroys the PeerConnectionFactory (along
// with the networking thread on which this message is posted). Also affects
// tests, with a workaround in
// AutoSocketServerThread::~AutoSocketServerThread.
RTC_LOG(LS_VERBOSE) << ToString() << ": Connection destroyed";
port_->thread()->Post(RTC_FROM_HERE, this, MSG_DELETE);
LogCandidatePairConfig(webrtc::IceCandidatePairConfigType::kDestroyed);
}
void Connection::FailAndDestroy() {
set_state(IceCandidatePairState::FAILED);
Destroy();
}
void Connection::FailAndPrune() {
set_state(IceCandidatePairState::FAILED);
Prune();
}
void Connection::PrintPingsSinceLastResponse(std::string* s, size_t max) {
rtc::StringBuilder oss;
if (pings_since_last_response_.size() > max) {
for (size_t i = 0; i < max; i++) {
const SentPing& ping = pings_since_last_response_[i];
oss << rtc::hex_encode(ping.id) << " ";
}
oss << "... " << (pings_since_last_response_.size() - max) << " more";
} else {
for (const SentPing& ping : pings_since_last_response_) {
oss << rtc::hex_encode(ping.id) << " ";
}
}
*s = oss.str();
}
void Connection::UpdateState(int64_t now) {
int rtt = ConservativeRTTEstimate(rtt_);
if (RTC_LOG_CHECK_LEVEL(LS_VERBOSE)) {
std::string pings;
PrintPingsSinceLastResponse(&pings, 5);
RTC_LOG(LS_VERBOSE) << ToString()
<< ": UpdateState()"
", ms since last received response="
<< now - last_ping_response_received_
<< ", ms since last received data="
<< now - last_data_received_ << ", rtt=" << rtt
<< ", pings_since_last_response=" << pings;
}
// Check the writable state. (The order of these checks is important.)
//
// Before becoming unwritable, we allow for a fixed number of pings to fail
// (i.e., receive no response). We also have to give the response time to
// get back, so we include a conservative estimate of this.
//
// Before timing out writability, we give a fixed amount of time. This is to
// allow for changes in network conditions.
if ((write_state_ == STATE_WRITABLE) &&
TooManyFailures(pings_since_last_response_, unwritable_min_checks(), rtt,
now) &&
TooLongWithoutResponse(pings_since_last_response_, unwritable_timeout(),
now)) {
uint32_t max_pings = unwritable_min_checks();
RTC_LOG(LS_INFO) << ToString() << ": Unwritable after " << max_pings
<< " ping failures and "
<< now - pings_since_last_response_[0].sent_time
<< " ms without a response,"
" ms since last received ping="
<< now - last_ping_received_
<< " ms since last received data="
<< now - last_data_received_ << " rtt=" << rtt;
set_write_state(STATE_WRITE_UNRELIABLE);
}
if ((write_state_ == STATE_WRITE_UNRELIABLE ||
write_state_ == STATE_WRITE_INIT) &&
TooLongWithoutResponse(pings_since_last_response_, inactive_timeout(),
now)) {
RTC_LOG(LS_INFO) << ToString() << ": Timed out after "
<< now - pings_since_last_response_[0].sent_time
<< " ms without a response, rtt=" << rtt;
set_write_state(STATE_WRITE_TIMEOUT);
}
// Update the receiving state.
UpdateReceiving(now);
if (dead(now)) {
Destroy();
}
}
void Connection::Ping(int64_t now) {
last_ping_sent_ = now;
ConnectionRequest* req = new ConnectionRequest(this);
// If not using renomination, we use "1" to mean "nominated" and "0" to mean
// "not nominated". If using renomination, values greater than 1 are used for
// re-nominated pairs.
int nomination = use_candidate_attr_ ? 1 : 0;
if (nomination_ > 0) {
nomination = nomination_;
}
pings_since_last_response_.push_back(SentPing(req->id(), now, nomination));
RTC_LOG(LS_VERBOSE) << ToString() << ": Sending STUN ping, id="
<< rtc::hex_encode(req->id())
<< ", nomination=" << nomination_;
requests_.Send(req);
state_ = IceCandidatePairState::IN_PROGRESS;
num_pings_sent_++;
}
void Connection::ReceivedPing(const absl::optional<std::string>& request_id) {
last_ping_received_ = rtc::TimeMillis();
last_ping_id_received_ = request_id;
UpdateReceiving(last_ping_received_);
}
void Connection::HandlePiggybackCheckAcknowledgementIfAny(StunMessage* msg) {
RTC_DCHECK(msg->type() == STUN_BINDING_REQUEST);
const StunByteStringAttribute* last_ice_check_received_attr =
msg->GetByteString(STUN_ATTR_LAST_ICE_CHECK_RECEIVED);
if (last_ice_check_received_attr) {
const std::string request_id = last_ice_check_received_attr->GetString();
auto iter = absl::c_find_if(
pings_since_last_response_,
[&request_id](const SentPing& ping) { return ping.id == request_id; });
if (iter != pings_since_last_response_.end()) {
rtc::LoggingSeverity sev = !writable() ? rtc::LS_INFO : rtc::LS_VERBOSE;
RTC_LOG_V(sev) << ToString()
<< ": Received piggyback STUN ping response, id="
<< rtc::hex_encode(request_id);
const int64_t rtt = rtc::TimeMillis() - iter->sent_time;
ReceivedPingResponse(rtt, request_id, iter->nomination);
}
}
}
void Connection::ReceivedPingResponse(
int rtt,
const std::string& request_id,
const absl::optional<uint32_t>& nomination) {
RTC_DCHECK_GE(rtt, 0);
// We've already validated that this is a STUN binding response with
// the correct local and remote username for this connection.
// So if we're not already, become writable. We may be bringing a pruned
// connection back to life, but if we don't really want it, we can always
// prune it again.
if (nomination && nomination.value() > acked_nomination_) {
acked_nomination_ = nomination.value();
}
int64_t now = rtc::TimeMillis();
total_round_trip_time_ms_ += rtt;
current_round_trip_time_ms_ = static_cast<uint32_t>(rtt);
rtt_estimate_.AddSample(now, rtt);
pings_since_last_response_.clear();
last_ping_response_received_ = now;
UpdateReceiving(last_ping_response_received_);
set_write_state(STATE_WRITABLE);
set_state(IceCandidatePairState::SUCCEEDED);
if (rtt_samples_ > 0) {
rtt_ = rtc::GetNextMovingAverage(rtt_, rtt, RTT_RATIO);
} else {
rtt_ = rtt;
}
rtt_samples_++;
}
bool Connection::dead(int64_t now) const {
if (last_received() > 0) {
// If it has ever received anything, we keep it alive until it hasn't
// received anything for DEAD_CONNECTION_RECEIVE_TIMEOUT. This covers the
// normal case of a successfully used connection that stops working. This
// also allows a remote peer to continue pinging over a locally inactive
// (pruned) connection.
return (now > (last_received() + DEAD_CONNECTION_RECEIVE_TIMEOUT));
}
if (active()) {
// If it has never received anything, keep it alive as long as it is
// actively pinging and not pruned. Otherwise, the connection might be
// deleted before it has a chance to ping. This is the normal case for a
// new connection that is pinging but hasn't received anything yet.
return false;
}
// If it has never received anything and is not actively pinging (pruned), we
// keep it around for at least MIN_CONNECTION_LIFETIME to prevent connections
// from being pruned too quickly during a network change event when two
// networks would be up simultaneously but only for a brief period.
return now > (time_created_ms_ + MIN_CONNECTION_LIFETIME);
}
bool Connection::stable(int64_t now) const {
// A connection is stable if it's RTT has converged and it isn't missing any
// responses. We should send pings at a higher rate until the RTT converges
// and whenever a ping response is missing (so that we can detect
// unwritability faster)
return rtt_converged() && !missing_responses(now);
}
std::string Connection::ToDebugId() const {
return rtc::ToHex(reinterpret_cast<uintptr_t>(this));
}
uint32_t Connection::ComputeNetworkCost() const {
// TODO(honghaiz): Will add rtt as part of the network cost.
return port()->network_cost() + remote_candidate_.network_cost();
}
std::string Connection::ToString() const {
const absl::string_view CONNECT_STATE_ABBREV[2] = {
"-", // not connected (false)
"C", // connected (true)
};
const absl::string_view RECEIVE_STATE_ABBREV[2] = {
"-", // not receiving (false)
"R", // receiving (true)
};
const absl::string_view WRITE_STATE_ABBREV[4] = {
"W", // STATE_WRITABLE
"w", // STATE_WRITE_UNRELIABLE
"-", // STATE_WRITE_INIT
"x", // STATE_WRITE_TIMEOUT
};
const absl::string_view ICESTATE[4] = {
"W", // STATE_WAITING
"I", // STATE_INPROGRESS
"S", // STATE_SUCCEEDED
"F" // STATE_FAILED
};
const absl::string_view SELECTED_STATE_ABBREV[2] = {
"-", // candidate pair not selected (false)
"S", // selected (true)
};
const Candidate& local = local_candidate();
const Candidate& remote = remote_candidate();
rtc::StringBuilder ss;
ss << "Conn[" << ToDebugId() << ":" << port_->content_name() << ":"
<< port_->Network()->ToString() << ":" << local.id() << ":"
<< local.component() << ":" << local.generation() << ":" << local.type()
<< ":" << local.protocol() << ":" << local.address().ToSensitiveString()
<< "->" << remote.id() << ":" << remote.component() << ":"
<< remote.priority() << ":" << remote.type() << ":" << remote.protocol()
<< ":" << remote.address().ToSensitiveString() << "|"
<< CONNECT_STATE_ABBREV[connected()] << RECEIVE_STATE_ABBREV[receiving()]
<< WRITE_STATE_ABBREV[write_state()] << ICESTATE[static_cast<int>(state())]
<< "|" << SELECTED_STATE_ABBREV[selected()] << "|" << remote_nomination()
<< "|" << nomination() << "|" << priority() << "|";
if (rtt_ < DEFAULT_RTT) {
ss << rtt_ << "]";
} else {
ss << "-]";
}
return ss.Release();
}
std::string Connection::ToSensitiveString() const {
return ToString();
}
const webrtc::IceCandidatePairDescription& Connection::ToLogDescription() {
if (log_description_.has_value()) {
return log_description_.value();
}
const Candidate& local = local_candidate();
const Candidate& remote = remote_candidate();
const rtc::Network* network = port()->Network();
log_description_ = webrtc::IceCandidatePairDescription();
log_description_->local_candidate_type =
GetCandidateTypeByString(local.type());
log_description_->local_relay_protocol =
GetProtocolByString(local.relay_protocol());
log_description_->local_network_type = ConvertNetworkType(network->type());
log_description_->local_address_family =
GetAddressFamilyByInt(local.address().family());
log_description_->remote_candidate_type =
GetCandidateTypeByString(remote.type());
log_description_->remote_address_family =
GetAddressFamilyByInt(remote.address().family());
log_description_->candidate_pair_protocol =
GetProtocolByString(local.protocol());
return log_description_.value();
}
void Connection::LogCandidatePairConfig(
webrtc::IceCandidatePairConfigType type) {
if (ice_event_log_ == nullptr) {
return;
}
ice_event_log_->LogCandidatePairConfig(type, id(), ToLogDescription());
}
void Connection::LogCandidatePairEvent(webrtc::IceCandidatePairEventType type,
uint32_t transaction_id) {
if (ice_event_log_ == nullptr) {
return;
}
ice_event_log_->LogCandidatePairEvent(type, id(), transaction_id);
}
void Connection::OnConnectionRequestResponse(ConnectionRequest* request,
StunMessage* response) {
// Log at LS_INFO if we receive a ping response on an unwritable
// connection.
rtc::LoggingSeverity sev = !writable() ? rtc::LS_INFO : rtc::LS_VERBOSE;
int rtt = request->Elapsed();
if (RTC_LOG_CHECK_LEVEL_V(sev)) {
std::string pings;
PrintPingsSinceLastResponse(&pings, 5);
RTC_LOG_V(sev) << ToString() << ": Received STUN ping response, id="
<< rtc::hex_encode(request->id())
<< ", code=0" // Makes logging easier to parse.
", rtt="
<< rtt << ", pings_since_last_response=" << pings;
}
absl::optional<uint32_t> nomination;
const std::string request_id = request->id();
auto iter = absl::c_find_if(
pings_since_last_response_,
[&request_id](const SentPing& ping) { return ping.id == request_id; });
if (iter != pings_since_last_response_.end()) {
nomination.emplace(iter->nomination);
}
ReceivedPingResponse(rtt, request_id, nomination);
stats_.recv_ping_responses++;
LogCandidatePairEvent(
webrtc::IceCandidatePairEventType::kCheckResponseReceived,
response->reduced_transaction_id());
MaybeUpdateLocalCandidate(request, response);
}
void Connection::OnConnectionRequestErrorResponse(ConnectionRequest* request,
StunMessage* response) {
int error_code = response->GetErrorCodeValue();
RTC_LOG(LS_WARNING) << ToString() << ": Received STUN error response id="
<< rtc::hex_encode(request->id())
<< " code=" << error_code
<< " rtt=" << request->Elapsed();
if (error_code == STUN_ERROR_UNKNOWN_ATTRIBUTE ||
error_code == STUN_ERROR_SERVER_ERROR ||
error_code == STUN_ERROR_UNAUTHORIZED) {
// Recoverable error, retry
} else if (error_code == STUN_ERROR_STALE_CREDENTIALS) {
// Race failure, retry
} else if (error_code == STUN_ERROR_ROLE_CONFLICT) {
HandleRoleConflictFromPeer();
} else {
// This is not a valid connection.
RTC_LOG(LS_ERROR) << ToString()
<< ": Received STUN error response, code=" << error_code
<< "; killing connection";
FailAndDestroy();
}
}
void Connection::OnConnectionRequestTimeout(ConnectionRequest* request) {
// Log at LS_INFO if we miss a ping on a writable connection.
rtc::LoggingSeverity sev = writable() ? rtc::LS_INFO : rtc::LS_VERBOSE;
RTC_LOG_V(sev) << ToString() << ": Timing-out STUN ping "
<< rtc::hex_encode(request->id()) << " after "
<< request->Elapsed() << " ms";
}
void Connection::OnConnectionRequestSent(ConnectionRequest* request) {
// Log at LS_INFO if we send a ping on an unwritable connection.
rtc::LoggingSeverity sev = !writable() ? rtc::LS_INFO : rtc::LS_VERBOSE;
RTC_LOG_V(sev) << ToString()
<< ": Sent STUN ping, id=" << rtc::hex_encode(request->id())
<< ", use_candidate=" << use_candidate_attr()
<< ", nomination=" << nomination();
stats_.sent_ping_requests_total++;
LogCandidatePairEvent(webrtc::IceCandidatePairEventType::kCheckSent,
request->reduced_transaction_id());
if (stats_.recv_ping_responses == 0) {
stats_.sent_ping_requests_before_first_response++;
}
}
void Connection::HandleRoleConflictFromPeer() {
port_->SignalRoleConflict(port_);
}
void Connection::MaybeSetRemoteIceParametersAndGeneration(
const IceParameters& ice_params,
int generation) {
if (remote_candidate_.username() == ice_params.ufrag &&
remote_candidate_.password().empty()) {
remote_candidate_.set_password(ice_params.pwd);
}
// TODO(deadbeef): A value of '0' for the generation is used for both
// generation 0 and "generation unknown". It should be changed to an
// absl::optional to fix this.
if (remote_candidate_.username() == ice_params.ufrag &&
remote_candidate_.password() == ice_params.pwd &&
remote_candidate_.generation() == 0) {
remote_candidate_.set_generation(generation);
}
}
void Connection::MaybeUpdatePeerReflexiveCandidate(
const Candidate& new_candidate) {
if (remote_candidate_.type() == PRFLX_PORT_TYPE &&
new_candidate.type() != PRFLX_PORT_TYPE &&
remote_candidate_.protocol() == new_candidate.protocol() &&
remote_candidate_.address() == new_candidate.address() &&
remote_candidate_.username() == new_candidate.username() &&
remote_candidate_.password() == new_candidate.password() &&
remote_candidate_.generation() == new_candidate.generation()) {
remote_candidate_ = new_candidate;
}
}
void Connection::OnMessage(rtc::Message* pmsg) {
RTC_DCHECK(pmsg->message_id == MSG_DELETE);
RTC_LOG(LS_INFO) << "Connection deleted with number of pings sent: "
<< num_pings_sent_;
SignalDestroyed(this);
delete this;
}
int64_t Connection::last_received() const {
return std::max(last_data_received_,
std::max(last_ping_received_, last_ping_response_received_));
}
ConnectionInfo Connection::stats() {
stats_.recv_bytes_second = round(recv_rate_tracker_.ComputeRate());
stats_.recv_total_bytes = recv_rate_tracker_.TotalSampleCount();
stats_.sent_bytes_second = round(send_rate_tracker_.ComputeRate());
stats_.sent_total_bytes = send_rate_tracker_.TotalSampleCount();
stats_.receiving = receiving_;
stats_.writable = write_state_ == STATE_WRITABLE;
stats_.timeout = write_state_ == STATE_WRITE_TIMEOUT;
stats_.new_connection = !reported_;
stats_.rtt = rtt_;
stats_.key = this;
stats_.state = state_;
stats_.priority = priority();
stats_.nominated = nominated();
stats_.total_round_trip_time_ms = total_round_trip_time_ms_;
stats_.current_round_trip_time_ms = current_round_trip_time_ms_;
stats_.local_candidate = local_candidate();
stats_.remote_candidate = remote_candidate();
return stats_;
}
void Connection::MaybeUpdateLocalCandidate(ConnectionRequest* request,
StunMessage* response) {
// RFC 5245
// The agent checks the mapped address from the STUN response. If the
// transport address does not match any of the local candidates that the
// agent knows about, the mapped address represents a new candidate -- a
// peer reflexive candidate.
const StunAddressAttribute* addr =
response->GetAddress(STUN_ATTR_XOR_MAPPED_ADDRESS);
if (!addr) {
RTC_LOG(LS_WARNING)
<< "Connection::OnConnectionRequestResponse - "
"No MAPPED-ADDRESS or XOR-MAPPED-ADDRESS found in the "
"stun response message";
return;
}
for (size_t i = 0; i < port_->Candidates().size(); ++i) {
if (port_->Candidates()[i].address() == addr->GetAddress()) {
if (local_candidate_index_ != i) {
RTC_LOG(LS_INFO) << ToString()
<< ": Updating local candidate type to srflx.";
local_candidate_index_ = i;
// SignalStateChange to force a re-sort in P2PTransportChannel as this
// Connection's local candidate has changed.
SignalStateChange(this);
}
return;
}
}
// RFC 5245
// Its priority is set equal to the value of the PRIORITY attribute
// in the Binding request.
const StunUInt32Attribute* priority_attr =
request->msg()->GetUInt32(STUN_ATTR_PRIORITY);
if (!priority_attr) {
RTC_LOG(LS_WARNING) << "Connection::OnConnectionRequestResponse - "
"No STUN_ATTR_PRIORITY found in the "
"stun response message";
return;
}
const uint32_t priority = priority_attr->value();
std::string id = rtc::CreateRandomString(8);
Candidate new_local_candidate;
new_local_candidate.set_id(id);
new_local_candidate.set_component(local_candidate().component());
new_local_candidate.set_type(PRFLX_PORT_TYPE);
new_local_candidate.set_protocol(local_candidate().protocol());
new_local_candidate.set_address(addr->GetAddress());
new_local_candidate.set_priority(priority);
new_local_candidate.set_username(local_candidate().username());
new_local_candidate.set_password(local_candidate().password());
new_local_candidate.set_network_name(local_candidate().network_name());
new_local_candidate.set_network_type(local_candidate().network_type());
new_local_candidate.set_related_address(local_candidate().address());
new_local_candidate.set_generation(local_candidate().generation());
new_local_candidate.set_foundation(Port::ComputeFoundation(
PRFLX_PORT_TYPE, local_candidate().protocol(),
local_candidate().relay_protocol(), local_candidate().address()));
new_local_candidate.set_network_id(local_candidate().network_id());
new_local_candidate.set_network_cost(local_candidate().network_cost());
// Change the local candidate of this Connection to the new prflx candidate.
RTC_LOG(LS_INFO) << ToString() << ": Updating local candidate type to prflx.";
local_candidate_index_ = port_->AddPrflxCandidate(new_local_candidate);
// SignalStateChange to force a re-sort in P2PTransportChannel as this
// Connection's local candidate has changed.
SignalStateChange(this);
}
bool Connection::rtt_converged() const {
return rtt_samples_ > (RTT_RATIO + 1);
}
bool Connection::missing_responses(int64_t now) const {
if (pings_since_last_response_.empty()) {
return false;
}
int64_t waiting = now - pings_since_last_response_[0].sent_time;
return waiting > 2 * rtt();
}
bool Connection::TooManyOutstandingPings(
const absl::optional<int>& max_outstanding_pings) const {
if (!max_outstanding_pings.has_value()) {
return false;
}
if (static_cast<int>(pings_since_last_response_.size()) <
*max_outstanding_pings) {
return false;
}
return true;
}
ProxyConnection::ProxyConnection(Port* port,
size_t index,
const Candidate& remote_candidate)
: Connection(port, index, remote_candidate) {}
int ProxyConnection::Send(const void* data,
size_t size,
const rtc::PacketOptions& options) {
stats_.sent_total_packets++;
int sent =
port_->SendTo(data, size, remote_candidate_.address(), options, true);
if (sent <= 0) {
RTC_DCHECK(sent < 0);
error_ = port_->GetError();
stats_.sent_discarded_packets++;
} else {
send_rate_tracker_.AddSamples(sent);
}
return sent;
}
int ProxyConnection::GetError() {
return error_;
}
} // namespace cricket