blob: 8ab33a31185869b669416fbf1ccef98f1b14168e [file] [log] [blame]
/*
* 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 "p2p/base/port.h"
#include <math.h>
#include <algorithm>
#include <utility>
#include <vector>
#include "absl/memory/memory.h"
#include "p2p/base/portallocator.h"
#include "rtc_base/checks.h"
#include "rtc_base/crc32.h"
#include "rtc_base/helpers.h"
#include "rtc_base/logging.h"
#include "rtc_base/messagedigest.h"
#include "rtc_base/network.h"
#include "rtc_base/numerics/safe_minmax.h"
#include "rtc_base/stringencode.h"
#include "rtc_base/stringutils.h"
#include "rtc_base/third_party/base64/base64.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;
}
rtc::PacketInfoProtocolType ConvertProtocolTypeToPacketInfoProtocolType(
cricket::ProtocolType type) {
switch (type) {
case cricket::ProtocolType::PROTO_UDP:
return rtc::PacketInfoProtocolType::kUdp;
case cricket::ProtocolType::PROTO_TCP:
return rtc::PacketInfoProtocolType::kTcp;
case cricket::ProtocolType::PROTO_SSLTCP:
return rtc::PacketInfoProtocolType::kSsltcp;
case cricket::ProtocolType::PROTO_TLS:
return rtc::PacketInfoProtocolType::kTls;
default:
return rtc::PacketInfoProtocolType::kUnknown;
}
}
// 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
// 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
// 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
// The delay before we begin checking if this port is useless. We set
// it to a little higher than a total STUN timeout.
const int kPortTimeoutDelay = cricket::STUN_TOTAL_TIMEOUT + 5000;
// For packet loss estimation.
const int64_t kConsiderPacketLostAfter = 3000; // 3 seconds
// For packet loss estimation.
const int64_t kForgetPacketAfter = 30000; // 30 seconds
} // namespace
namespace cricket {
using webrtc::RTCErrorType;
using webrtc::RTCError;
// TODO(ronghuawu): Use "local", "srflx", "prflx" and "relay". But this requires
// the signaling part be updated correspondingly as well.
const char LOCAL_PORT_TYPE[] = "local";
const char STUN_PORT_TYPE[] = "stun";
const char PRFLX_PORT_TYPE[] = "prflx";
const char RELAY_PORT_TYPE[] = "relay";
static const char* const PROTO_NAMES[] = {UDP_PROTOCOL_NAME, TCP_PROTOCOL_NAME,
SSLTCP_PROTOCOL_NAME,
TLS_PROTOCOL_NAME};
const char* ProtoToString(ProtocolType proto) {
return PROTO_NAMES[proto];
}
bool StringToProto(const char* value, ProtocolType* proto) {
for (size_t i = 0; i <= PROTO_LAST; ++i) {
if (_stricmp(PROTO_NAMES[i], value) == 0) {
*proto = static_cast<ProtocolType>(i);
return true;
}
}
return false;
}
// RFC 6544, TCP candidate encoding rules.
const int DISCARD_PORT = 9;
const char TCPTYPE_ACTIVE_STR[] = "active";
const char TCPTYPE_PASSIVE_STR[] = "passive";
const char TCPTYPE_SIMOPEN_STR[] = "so";
// Foundation: An arbitrary string that is the same for two candidates
// that have the same type, base IP address, protocol (UDP, TCP,
// etc.), and STUN or TURN server. If any of these are different,
// then the foundation will be different. Two candidate pairs with
// the same foundation pairs are likely to have similar network
// characteristics. Foundations are used in the frozen algorithm.
static std::string ComputeFoundation(const std::string& type,
const std::string& protocol,
const std::string& relay_protocol,
const rtc::SocketAddress& base_address) {
std::ostringstream ost;
ost << type << base_address.ipaddr().ToString() << protocol << relay_protocol;
return rtc::ToString(rtc::ComputeCrc32(ost.str()));
}
CandidateStats::CandidateStats() = default;
CandidateStats::CandidateStats(const CandidateStats&) = default;
CandidateStats::CandidateStats(Candidate candidate) {
this->candidate = candidate;
}
CandidateStats::~CandidateStats() = default;
ConnectionInfo::ConnectionInfo()
: best_connection(false),
writable(false),
receiving(false),
timeout(false),
new_connection(false),
rtt(0),
sent_total_bytes(0),
sent_bytes_second(0),
sent_discarded_packets(0),
sent_total_packets(0),
sent_ping_requests_total(0),
sent_ping_requests_before_first_response(0),
sent_ping_responses(0),
recv_total_bytes(0),
recv_bytes_second(0),
recv_ping_requests(0),
recv_ping_responses(0),
key(nullptr),
state(IceCandidatePairState::WAITING),
priority(0),
nominated(false),
total_round_trip_time_ms(0) {}
ConnectionInfo::ConnectionInfo(const ConnectionInfo&) = default;
ConnectionInfo::~ConnectionInfo() = default;
Port::Port(rtc::Thread* thread,
const std::string& type,
rtc::PacketSocketFactory* factory,
rtc::Network* network,
const std::string& username_fragment,
const std::string& password)
: thread_(thread),
factory_(factory),
type_(type),
send_retransmit_count_attribute_(false),
network_(network),
min_port_(0),
max_port_(0),
component_(ICE_CANDIDATE_COMPONENT_DEFAULT),
generation_(0),
ice_username_fragment_(username_fragment),
password_(password),
timeout_delay_(kPortTimeoutDelay),
enable_port_packets_(false),
ice_role_(ICEROLE_UNKNOWN),
tiebreaker_(0),
shared_socket_(true) {
Construct();
}
Port::Port(rtc::Thread* thread,
const std::string& type,
rtc::PacketSocketFactory* factory,
rtc::Network* network,
uint16_t min_port,
uint16_t max_port,
const std::string& username_fragment,
const std::string& password)
: thread_(thread),
factory_(factory),
type_(type),
send_retransmit_count_attribute_(false),
network_(network),
min_port_(min_port),
max_port_(max_port),
component_(ICE_CANDIDATE_COMPONENT_DEFAULT),
generation_(0),
ice_username_fragment_(username_fragment),
password_(password),
timeout_delay_(kPortTimeoutDelay),
enable_port_packets_(false),
ice_role_(ICEROLE_UNKNOWN),
tiebreaker_(0),
shared_socket_(false) {
RTC_DCHECK(factory_ != NULL);
Construct();
}
void Port::Construct() {
// TODO(pthatcher): Remove this old behavior once we're sure no one
// relies on it. If the username_fragment and password are empty,
// we should just create one.
if (ice_username_fragment_.empty()) {
RTC_DCHECK(password_.empty());
ice_username_fragment_ = rtc::CreateRandomString(ICE_UFRAG_LENGTH);
password_ = rtc::CreateRandomString(ICE_PWD_LENGTH);
}
network_->SignalTypeChanged.connect(this, &Port::OnNetworkTypeChanged);
network_cost_ = network_->GetCost();
thread_->PostDelayed(RTC_FROM_HERE, timeout_delay_, this,
MSG_DESTROY_IF_DEAD);
RTC_LOG(LS_INFO) << ToString() << ": Port created with network cost "
<< network_cost_;
}
Port::~Port() {
// Delete all of the remaining connections. We copy the list up front
// because each deletion will cause it to be modified.
std::vector<Connection*> list;
AddressMap::iterator iter = connections_.begin();
while (iter != connections_.end()) {
list.push_back(iter->second);
++iter;
}
for (uint32_t i = 0; i < list.size(); i++)
delete list[i];
}
const std::string& Port::Type() const {
return type_;
}
rtc::Network* Port::Network() const {
return network_;
}
IceRole Port::GetIceRole() const {
return ice_role_;
}
void Port::SetIceRole(IceRole role) {
ice_role_ = role;
}
void Port::SetIceTiebreaker(uint64_t tiebreaker) {
tiebreaker_ = tiebreaker;
}
uint64_t Port::IceTiebreaker() const {
return tiebreaker_;
}
bool Port::SharedSocket() const {
return shared_socket_;
}
void Port::SetIceParameters(int component,
const std::string& username_fragment,
const std::string& password) {
component_ = component;
ice_username_fragment_ = username_fragment;
password_ = password;
for (Candidate& c : candidates_) {
c.set_component(component);
c.set_username(username_fragment);
c.set_password(password);
}
}
const std::vector<Candidate>& Port::Candidates() const {
return candidates_;
}
Connection* Port::GetConnection(const rtc::SocketAddress& remote_addr) {
AddressMap::const_iterator iter = connections_.find(remote_addr);
if (iter != connections_.end())
return iter->second;
else
return NULL;
}
void Port::AddAddress(const rtc::SocketAddress& address,
const rtc::SocketAddress& base_address,
const rtc::SocketAddress& related_address,
const std::string& protocol,
const std::string& relay_protocol,
const std::string& tcptype,
const std::string& type,
uint32_t type_preference,
uint32_t relay_preference,
bool final) {
AddAddress(address, base_address, related_address, protocol, relay_protocol,
tcptype, type, type_preference, relay_preference, "", final);
}
void Port::AddAddress(const rtc::SocketAddress& address,
const rtc::SocketAddress& base_address,
const rtc::SocketAddress& related_address,
const std::string& protocol,
const std::string& relay_protocol,
const std::string& tcptype,
const std::string& type,
uint32_t type_preference,
uint32_t relay_preference,
const std::string& url,
bool final) {
if (protocol == TCP_PROTOCOL_NAME && type == LOCAL_PORT_TYPE) {
RTC_DCHECK(!tcptype.empty());
}
std::string foundation =
ComputeFoundation(type, protocol, relay_protocol, base_address);
Candidate c(component_, protocol, address, 0U, username_fragment(), password_,
type, generation_, foundation, network_->id(), network_cost_);
c.set_priority(
c.GetPriority(type_preference, network_->preference(), relay_preference));
c.set_relay_protocol(relay_protocol);
c.set_tcptype(tcptype);
c.set_network_name(network_->name());
c.set_network_type(network_->type());
c.set_related_address(related_address);
c.set_url(url);
candidates_.push_back(c);
SignalCandidateReady(this, c);
if (final) {
SignalPortComplete(this);
}
}
void Port::AddOrReplaceConnection(Connection* conn) {
auto ret = connections_.insert(
std::make_pair(conn->remote_candidate().address(), conn));
// If there is a different connection on the same remote address, replace
// it with the new one and destroy the old one.
if (ret.second == false && ret.first->second != conn) {
RTC_LOG(LS_WARNING)
<< ToString()
<< ": A new connection was created on an existing remote address. "
"New remote candidate: "
<< conn->remote_candidate().ToString();
ret.first->second->SignalDestroyed.disconnect(this);
ret.first->second->Destroy();
ret.first->second = conn;
}
conn->SignalDestroyed.connect(this, &Port::OnConnectionDestroyed);
SignalConnectionCreated(this, conn);
}
void Port::OnReadPacket(const char* data,
size_t size,
const rtc::SocketAddress& addr,
ProtocolType proto) {
// If the user has enabled port packets, just hand this over.
if (enable_port_packets_) {
SignalReadPacket(this, data, size, addr);
return;
}
// If this is an authenticated STUN request, then signal unknown address and
// send back a proper binding response.
std::unique_ptr<IceMessage> msg;
std::string remote_username;
if (!GetStunMessage(data, size, addr, &msg, &remote_username)) {
RTC_LOG(LS_ERROR) << ToString()
<< ": Received non-STUN packet from unknown address: "
<< addr.ToSensitiveString();
} else if (!msg) {
// STUN message handled already
} else if (msg->type() == STUN_BINDING_REQUEST) {
RTC_LOG(LS_INFO) << "Received STUN ping id="
<< rtc::hex_encode(msg->transaction_id())
<< " from unknown address " << addr.ToSensitiveString();
// We need to signal an unknown address before we handle any role conflict
// below. Otherwise there would be no candidate pair and TURN entry created
// to send the error response in case of a role conflict.
SignalUnknownAddress(this, addr, proto, msg.get(), remote_username, false);
// Check for role conflicts.
if (!MaybeIceRoleConflict(addr, msg.get(), remote_username)) {
RTC_LOG(LS_INFO) << "Received conflicting role from the peer.";
return;
}
} else {
// NOTE(tschmelcher): STUN_BINDING_RESPONSE is benign. It occurs if we
// pruned a connection for this port while it had STUN requests in flight,
// because we then get back responses for them, which this code correctly
// does not handle.
if (msg->type() != STUN_BINDING_RESPONSE) {
RTC_LOG(LS_ERROR) << ToString()
<< ": Received unexpected STUN message type: "
<< msg->type() << " from unknown address: "
<< addr.ToSensitiveString();
}
}
}
void Port::OnReadyToSend() {
AddressMap::iterator iter = connections_.begin();
for (; iter != connections_.end(); ++iter) {
iter->second->OnReadyToSend();
}
}
size_t Port::AddPrflxCandidate(const Candidate& local) {
candidates_.push_back(local);
return (candidates_.size() - 1);
}
bool Port::GetStunMessage(const char* data,
size_t size,
const rtc::SocketAddress& addr,
std::unique_ptr<IceMessage>* out_msg,
std::string* out_username) {
// NOTE: This could clearly be optimized to avoid allocating any memory.
// However, at the data rates we'll be looking at on the client side,
// this probably isn't worth worrying about.
RTC_DCHECK(out_msg != NULL);
RTC_DCHECK(out_username != NULL);
out_username->clear();
// Don't bother parsing the packet if we can tell it's not STUN.
// In ICE mode, all STUN packets will have a valid fingerprint.
if (!StunMessage::ValidateFingerprint(data, size)) {
return false;
}
// Parse the request message. If the packet is not a complete and correct
// STUN message, then ignore it.
std::unique_ptr<IceMessage> stun_msg(new IceMessage());
rtc::ByteBufferReader buf(data, size);
if (!stun_msg->Read(&buf) || (buf.Length() > 0)) {
return false;
}
if (stun_msg->type() == STUN_BINDING_REQUEST) {
// Check for the presence of USERNAME and MESSAGE-INTEGRITY (if ICE) first.
// If not present, fail with a 400 Bad Request.
if (!stun_msg->GetByteString(STUN_ATTR_USERNAME) ||
!stun_msg->GetByteString(STUN_ATTR_MESSAGE_INTEGRITY)) {
RTC_LOG(LS_ERROR) << ToString()
<< ": Received STUN request without username/M-I from: "
<< addr.ToSensitiveString();
SendBindingErrorResponse(stun_msg.get(), addr, STUN_ERROR_BAD_REQUEST,
STUN_ERROR_REASON_BAD_REQUEST);
return true;
}
// If the username is bad or unknown, fail with a 401 Unauthorized.
std::string local_ufrag;
std::string remote_ufrag;
if (!ParseStunUsername(stun_msg.get(), &local_ufrag, &remote_ufrag) ||
local_ufrag != username_fragment()) {
RTC_LOG(LS_ERROR) << ToString()
<< ": Received STUN request with bad local username "
<< local_ufrag << " from " << addr.ToSensitiveString();
SendBindingErrorResponse(stun_msg.get(), addr, STUN_ERROR_UNAUTHORIZED,
STUN_ERROR_REASON_UNAUTHORIZED);
return true;
}
// If ICE, and the MESSAGE-INTEGRITY is bad, fail with a 401 Unauthorized
if (!stun_msg->ValidateMessageIntegrity(data, size, password_)) {
RTC_LOG(LS_ERROR) << ToString()
<< ": Received STUN request with bad M-I from "
<< addr.ToSensitiveString()
<< ", password_=" << password_;
SendBindingErrorResponse(stun_msg.get(), addr, STUN_ERROR_UNAUTHORIZED,
STUN_ERROR_REASON_UNAUTHORIZED);
return true;
}
out_username->assign(remote_ufrag);
} else if ((stun_msg->type() == STUN_BINDING_RESPONSE) ||
(stun_msg->type() == STUN_BINDING_ERROR_RESPONSE)) {
if (stun_msg->type() == STUN_BINDING_ERROR_RESPONSE) {
if (const StunErrorCodeAttribute* error_code = stun_msg->GetErrorCode()) {
RTC_LOG(LS_ERROR) << ToString()
<< ": Received STUN binding error: class="
<< error_code->eclass()
<< " number=" << error_code->number() << " reason='"
<< error_code->reason() << "' from "
<< addr.ToSensitiveString();
// Return message to allow error-specific processing
} else {
RTC_LOG(LS_ERROR)
<< ToString()
<< ": Received STUN binding error without a error code from "
<< addr.ToSensitiveString();
return true;
}
}
// NOTE: Username should not be used in verifying response messages.
out_username->clear();
} else if (stun_msg->type() == STUN_BINDING_INDICATION) {
RTC_LOG(LS_VERBOSE) << ToString()
<< ": Received STUN binding indication: from "
<< addr.ToSensitiveString();
out_username->clear();
// No stun attributes will be verified, if it's stun indication message.
// Returning from end of the this method.
} else {
RTC_LOG(LS_ERROR) << ToString()
<< ": Received STUN packet with invalid type ("
<< stun_msg->type() << ") from "
<< addr.ToSensitiveString();
return true;
}
// Return the STUN message found.
*out_msg = std::move(stun_msg);
return true;
}
bool Port::IsCompatibleAddress(const rtc::SocketAddress& addr) {
// Get a representative IP for the Network this port is configured to use.
rtc::IPAddress ip = network_->GetBestIP();
// We use single-stack sockets, so families must match.
if (addr.family() != ip.family()) {
return false;
}
// Link-local IPv6 ports can only connect to other link-local IPv6 ports.
if (ip.family() == AF_INET6 &&
(IPIsLinkLocal(ip) != IPIsLinkLocal(addr.ipaddr()))) {
return false;
}
return true;
}
bool Port::ParseStunUsername(const StunMessage* stun_msg,
std::string* local_ufrag,
std::string* remote_ufrag) const {
// The packet must include a username that either begins or ends with our
// fragment. It should begin with our fragment if it is a request and it
// should end with our fragment if it is a response.
local_ufrag->clear();
remote_ufrag->clear();
const StunByteStringAttribute* username_attr =
stun_msg->GetByteString(STUN_ATTR_USERNAME);
if (username_attr == NULL)
return false;
// RFRAG:LFRAG
const std::string username = username_attr->GetString();
size_t colon_pos = username.find(":");
if (colon_pos == std::string::npos) {
return false;
}
*local_ufrag = username.substr(0, colon_pos);
*remote_ufrag = username.substr(colon_pos + 1, username.size());
return true;
}
bool Port::MaybeIceRoleConflict(const rtc::SocketAddress& addr,
IceMessage* stun_msg,
const std::string& remote_ufrag) {
// Validate ICE_CONTROLLING or ICE_CONTROLLED attributes.
bool ret = true;
IceRole remote_ice_role = ICEROLE_UNKNOWN;
uint64_t remote_tiebreaker = 0;
const StunUInt64Attribute* stun_attr =
stun_msg->GetUInt64(STUN_ATTR_ICE_CONTROLLING);
if (stun_attr) {
remote_ice_role = ICEROLE_CONTROLLING;
remote_tiebreaker = stun_attr->value();
}
// If |remote_ufrag| is same as port local username fragment and
// tie breaker value received in the ping message matches port
// tiebreaker value this must be a loopback call.
// We will treat this as valid scenario.
if (remote_ice_role == ICEROLE_CONTROLLING &&
username_fragment() == remote_ufrag &&
remote_tiebreaker == IceTiebreaker()) {
return true;
}
stun_attr = stun_msg->GetUInt64(STUN_ATTR_ICE_CONTROLLED);
if (stun_attr) {
remote_ice_role = ICEROLE_CONTROLLED;
remote_tiebreaker = stun_attr->value();
}
switch (ice_role_) {
case ICEROLE_CONTROLLING:
if (ICEROLE_CONTROLLING == remote_ice_role) {
if (remote_tiebreaker >= tiebreaker_) {
SignalRoleConflict(this);
} else {
// Send Role Conflict (487) error response.
SendBindingErrorResponse(stun_msg, addr, STUN_ERROR_ROLE_CONFLICT,
STUN_ERROR_REASON_ROLE_CONFLICT);
ret = false;
}
}
break;
case ICEROLE_CONTROLLED:
if (ICEROLE_CONTROLLED == remote_ice_role) {
if (remote_tiebreaker < tiebreaker_) {
SignalRoleConflict(this);
} else {
// Send Role Conflict (487) error response.
SendBindingErrorResponse(stun_msg, addr, STUN_ERROR_ROLE_CONFLICT,
STUN_ERROR_REASON_ROLE_CONFLICT);
ret = false;
}
}
break;
default:
RTC_NOTREACHED();
}
return ret;
}
void Port::CreateStunUsername(const std::string& remote_username,
std::string* stun_username_attr_str) const {
stun_username_attr_str->clear();
*stun_username_attr_str = remote_username;
stun_username_attr_str->append(":");
stun_username_attr_str->append(username_fragment());
}
bool Port::HandleIncomingPacket(rtc::AsyncPacketSocket* socket,
const char* data,
size_t size,
const rtc::SocketAddress& remote_addr,
const rtc::PacketTime& packet_time) {
RTC_NOTREACHED();
return false;
}
bool Port::CanHandleIncomingPacketsFrom(const rtc::SocketAddress&) const {
return false;
}
void Port::SendBindingResponse(StunMessage* request,
const rtc::SocketAddress& addr) {
RTC_DCHECK(request->type() == STUN_BINDING_REQUEST);
// 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(absl::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(absl::make_unique<StunXorAddressAttribute>(
STUN_ATTR_XOR_MAPPED_ADDRESS, addr));
response.AddMessageIntegrity(password_);
response.AddFingerprint();
// Send the response message.
rtc::ByteBufferWriter buf;
response.Write(&buf);
rtc::PacketOptions options(DefaultDscpValue());
options.info_signaled_after_sent.packet_type =
rtc::PacketType::kIceConnectivityCheckResponse;
auto err = 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.
Connection* conn = GetConnection(addr);
rtc::LoggingSeverity sev =
(conn && !conn->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());
conn->stats_.sent_ping_responses++;
conn->LogCandidatePairEvent(
webrtc::IceCandidatePairEventType::kCheckResponseSent);
}
}
void Port::SendBindingErrorResponse(StunMessage* request,
const rtc::SocketAddress& addr,
int error_code,
const std::string& reason) {
RTC_DCHECK(request->type() == STUN_BINDING_REQUEST);
// Fill in the response message.
StunMessage response;
response.SetType(STUN_BINDING_ERROR_RESPONSE);
response.SetTransactionID(request->transaction_id());
// When doing GICE, we need to write out the error code incorrectly to
// maintain backwards compatiblility.
auto error_attr = StunAttribute::CreateErrorCode();
error_attr->SetCode(error_code);
error_attr->SetReason(reason);
response.AddAttribute(std::move(error_attr));
// Per Section 10.1.2, certain error cases don't get a MESSAGE-INTEGRITY,
// because we don't have enough information to determine the shared secret.
if (error_code != STUN_ERROR_BAD_REQUEST &&
error_code != STUN_ERROR_UNAUTHORIZED)
response.AddMessageIntegrity(password_);
response.AddFingerprint();
// Send the response message.
rtc::ByteBufferWriter buf;
response.Write(&buf);
rtc::PacketOptions options(DefaultDscpValue());
options.info_signaled_after_sent.packet_type =
rtc::PacketType::kIceConnectivityCheckResponse;
SendTo(buf.Data(), buf.Length(), addr, options, false);
RTC_LOG(LS_INFO) << ToString()
<< ": Sending STUN binding error: reason=" << reason
<< " to " << addr.ToSensitiveString();
}
void Port::KeepAliveUntilPruned() {
// If it is pruned, we won't bring it up again.
if (state_ == State::INIT) {
state_ = State::KEEP_ALIVE_UNTIL_PRUNED;
}
}
void Port::Prune() {
state_ = State::PRUNED;
thread_->Post(RTC_FROM_HERE, this, MSG_DESTROY_IF_DEAD);
}
void Port::OnMessage(rtc::Message* pmsg) {
RTC_DCHECK(pmsg->message_id == MSG_DESTROY_IF_DEAD);
bool dead =
(state_ == State::INIT || state_ == State::PRUNED) &&
connections_.empty() &&
rtc::TimeMillis() - last_time_all_connections_removed_ >= timeout_delay_;
if (dead) {
Destroy();
}
}
void Port::OnNetworkTypeChanged(const rtc::Network* network) {
RTC_DCHECK(network == network_);
UpdateNetworkCost();
}
std::string Port::ToString() const {
std::stringstream ss;
ss << "Port[" << std::hex << this << std::dec << ":" << content_name_ << ":"
<< component_ << ":" << generation_ << ":" << type_ << ":"
<< network_->ToString() << "]";
return ss.str();
}
// TODO(honghaiz): Make the network cost configurable from user setting.
void Port::UpdateNetworkCost() {
uint16_t new_cost = network_->GetCost();
if (network_cost_ == new_cost) {
return;
}
RTC_LOG(LS_INFO) << "Network cost changed from " << network_cost_ << " to "
<< new_cost
<< ". Number of candidates created: " << candidates_.size()
<< ". Number of connections created: "
<< connections_.size();
network_cost_ = new_cost;
for (cricket::Candidate& candidate : candidates_) {
candidate.set_network_cost(network_cost_);
}
// Network cost change will affect the connection selection criteria.
// Signal the connection state change on each connection to force a
// re-sort in P2PTransportChannel.
for (auto kv : connections_) {
Connection* conn = kv.second;
conn->SignalStateChange(conn);
}
}
void Port::EnablePortPackets() {
enable_port_packets_ = true;
}
void Port::OnConnectionDestroyed(Connection* conn) {
AddressMap::iterator iter =
connections_.find(conn->remote_candidate().address());
RTC_DCHECK(iter != connections_.end());
connections_.erase(iter);
HandleConnectionDestroyed(conn);
// Ports time out after all connections fail if it is not marked as
// "keep alive until pruned."
// Note: If a new connection is added after this message is posted, but it
// fails and is removed before kPortTimeoutDelay, then this message will
// not cause the Port to be destroyed.
if (connections_.empty()) {
last_time_all_connections_removed_ = rtc::TimeMillis();
thread_->PostDelayed(RTC_FROM_HERE, timeout_delay_, this,
MSG_DESTROY_IF_DEAD);
}
}
void Port::Destroy() {
RTC_DCHECK(connections_.empty());
RTC_LOG(LS_INFO) << ToString() << ": Port deleted";
SignalDestroyed(this);
delete this;
}
const std::string Port::username_fragment() const {
return ice_username_fragment_;
}
void Port::CopyPortInformationToPacketInfo(rtc::PacketInfo* info) const {
info->protocol = ConvertProtocolTypeToPacketInfoProtocolType(GetProtocol());
info->network_id = Network()->id();
}
// A ConnectionRequest is a simple STUN ping used to determine writability.
class ConnectionRequest : public StunRequest {
public:
explicit ConnectionRequest(Connection* connection)
: StunRequest(new IceMessage()), connection_(connection) {}
void Prepare(StunMessage* request) override {
request->SetType(STUN_BINDING_REQUEST);
std::string username;
connection_->port()->CreateStunUsername(
connection_->remote_candidate().username(), &username);
request->AddAttribute(absl::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(absl::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(absl::make_unique<StunUInt32Attribute>(
STUN_ATTR_NETWORK_INFO, network_info));
// Adding ICE_CONTROLLED or ICE_CONTROLLING attribute based on the role.
if (connection_->port()->GetIceRole() == ICEROLE_CONTROLLING) {
request->AddAttribute(absl::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(absl::make_unique<StunByteStringAttribute>(
STUN_ATTR_USE_CANDIDATE));
}
if (connection_->nomination() &&
connection_->nomination() != connection_->acked_nomination()) {
request->AddAttribute(absl::make_unique<StunUInt32Attribute>(
STUN_ATTR_NOMINATION, connection_->nomination()));
}
} else if (connection_->port()->GetIceRole() == ICEROLE_CONTROLLED) {
request->AddAttribute(absl::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(absl::make_unique<StunUInt32Attribute>(
STUN_ATTR_PRIORITY, prflx_priority));
// Adding Message Integrity attribute.
request->AddMessageIntegrity(connection_->remote_candidate().password());
// Adding Fingerprint.
request->AddFingerprint();
}
void OnResponse(StunMessage* response) override {
connection_->OnConnectionRequestResponse(this, response);
}
void OnErrorResponse(StunMessage* response) override {
connection_->OnConnectionRequestErrorResponse(this, response);
}
void OnTimeout() override { connection_->OnConnectionRequestTimeout(this); }
void OnSent() override {
connection_->OnConnectionRequestSent(this);
// Each request is sent only once. After a single delay , the request will
// time out.
timeout_ = true;
}
int resend_delay() override { return CONNECTION_RESPONSE_TIMEOUT; }
private:
Connection* connection_;
};
//
// Connection
//
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),
packet_loss_estimator_(kConsiderPacketLostAfter, kForgetPacketAfter),
reported_(false),
state_(IceCandidatePairState::WAITING),
time_created_ms_(rtc::TimeMillis()) {
// 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_;
}
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::receiving_timeout() const {
return receiving_timeout_.value_or(WEAK_CONNECTION_RECEIVE_TIMEOUT);
}
void Connection::OnSendStunPacket(const void* data,
size_t size,
StunRequest* req) {
rtc::PacketOptions options(port_->DefaultDscpValue());
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,
const rtc::PacketTime& packet_time) {
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);
// 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();
break;
default:
RTC_NOTREACHED();
break;
}
}
}
void Connection::HandleBindingRequest(IceMessage* msg) {
// This connection should now be receiving.
ReceivedPing();
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);
// This is a validated stun request from remote peer.
port_->SendBindingResponse(msg, remote_addr);
// 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);
}
}
}
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) {
std::ostringstream oss;
oss << std::boolalpha;
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_,
CONNECTION_WRITE_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));
packet_loss_estimator_.ExpectResponse(req->id(), now);
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() {
last_ping_received_ = rtc::TimeMillis();
UpdateReceiving(last_ping_received_);
}
void Connection::ReceivedPingResponse(int rtt, const std::string& request_id) {
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.
auto iter = std::find_if(
pings_since_last_response_.begin(), pings_since_last_response_.end(),
[request_id](const SentPing& ping) { return ping.id == request_id; });
if (iter != pings_since_last_response_.end() &&
iter->nomination > acked_nomination_) {
acked_nomination_ = iter->nomination;
}
total_round_trip_time_ms_ += rtt;
current_round_trip_time_ms_ = static_cast<uint32_t>(rtt);
pings_since_last_response_.clear();
last_ping_response_received_ = rtc::TimeMillis();
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 {
std::stringstream ss;
ss << std::hex << this;
return ss.str();
}
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 char CONNECT_STATE_ABBREV[2] = {
'-', // not connected (false)
'C', // connected (true)
};
const char RECEIVE_STATE_ABBREV[2] = {
'-', // not receiving (false)
'R', // receiving (true)
};
const char WRITE_STATE_ABBREV[4] = {
'W', // STATE_WRITABLE
'w', // STATE_WRITE_UNRELIABLE
'-', // STATE_WRITE_INIT
'x', // STATE_WRITE_TIMEOUT
};
const std::string ICESTATE[4] = {
"W", // STATE_WAITING
"I", // STATE_INPROGRESS
"S", // STATE_SUCCEEDED
"F" // STATE_FAILED
};
const std::string SELECTED_STATE_ABBREV[2] = {
"-", // candidate pair not selected (false)
"S", // selected (true)
};
const Candidate& local = local_candidate();
const Candidate& remote = remote_candidate();
std::stringstream 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.str();
}
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) {
if (ice_event_log_ == nullptr) {
return;
}
ice_event_log_->LogCandidatePairEvent(type, 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;
}
ReceivedPingResponse(rtt, request->id());
int64_t time_received = rtc::TimeMillis();
packet_loss_estimator_.ReceivedResponse(request->id(), time_received);
stats_.recv_ping_responses++;
LogCandidatePairEvent(
webrtc::IceCandidatePairEventType::kCheckResponseReceived);
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);
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_.local_candidate = local_candidate();
stats_.remote_candidate = remote_candidate();
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_;
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(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();
}
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