blob: 2e4e26d0d1da6dae450c3013a27b0dd19ad4018c [file] [log] [blame]
/*
* Copyright 2012 The WebRTC Project Authors. All rights reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include "webrtc/p2p/base/turnport.h"
#include <functional>
#include "webrtc/p2p/base/common.h"
#include "webrtc/p2p/base/stun.h"
#include "webrtc/base/asyncpacketsocket.h"
#include "webrtc/base/byteorder.h"
#include "webrtc/base/common.h"
#include "webrtc/base/logging.h"
#include "webrtc/base/nethelpers.h"
#include "webrtc/base/socketaddress.h"
#include "webrtc/base/stringencode.h"
namespace cricket {
// TODO(juberti): Move to stun.h when relay messages have been renamed.
static const int TURN_ALLOCATE_REQUEST = STUN_ALLOCATE_REQUEST;
// TODO(juberti): Extract to turnmessage.h
static const int TURN_DEFAULT_PORT = 3478;
static const int TURN_CHANNEL_NUMBER_START = 0x4000;
static const int TURN_PERMISSION_TIMEOUT = 5 * 60 * 1000; // 5 minutes
static const size_t TURN_CHANNEL_HEADER_SIZE = 4U;
// Retry at most twice (i.e. three different ALLOCATE requests) on
// STUN_ERROR_ALLOCATION_MISMATCH error per rfc5766.
static const size_t MAX_ALLOCATE_MISMATCH_RETRIES = 2;
inline bool IsTurnChannelData(uint16 msg_type) {
return ((msg_type & 0xC000) == 0x4000); // MSB are 0b01
}
static int GetRelayPreference(cricket::ProtocolType proto, bool secure) {
int relay_preference = ICE_TYPE_PREFERENCE_RELAY;
if (proto == cricket::PROTO_TCP) {
relay_preference -= 1;
if (secure)
relay_preference -= 1;
}
ASSERT(relay_preference >= 0);
return relay_preference;
}
class TurnAllocateRequest : public StunRequest {
public:
explicit TurnAllocateRequest(TurnPort* port);
void Prepare(StunMessage* request) override;
void OnSent() override;
void OnResponse(StunMessage* response) override;
void OnErrorResponse(StunMessage* response) override;
void OnTimeout() override;
private:
// Handles authentication challenge from the server.
void OnAuthChallenge(StunMessage* response, int code);
void OnTryAlternate(StunMessage* response, int code);
void OnUnknownAttribute(StunMessage* response);
TurnPort* port_;
};
class TurnRefreshRequest : public StunRequest {
public:
explicit TurnRefreshRequest(TurnPort* port);
void Prepare(StunMessage* request) override;
void OnSent() override;
void OnResponse(StunMessage* response) override;
void OnErrorResponse(StunMessage* response) override;
void OnTimeout() override;
void set_lifetime(int lifetime) { lifetime_ = lifetime; }
private:
TurnPort* port_;
int lifetime_;
};
class TurnCreatePermissionRequest : public StunRequest,
public sigslot::has_slots<> {
public:
TurnCreatePermissionRequest(TurnPort* port, TurnEntry* entry,
const rtc::SocketAddress& ext_addr);
void Prepare(StunMessage* request) override;
void OnSent() override;
void OnResponse(StunMessage* response) override;
void OnErrorResponse(StunMessage* response) override;
void OnTimeout() override;
private:
void OnEntryDestroyed(TurnEntry* entry);
TurnPort* port_;
TurnEntry* entry_;
rtc::SocketAddress ext_addr_;
};
class TurnChannelBindRequest : public StunRequest,
public sigslot::has_slots<> {
public:
TurnChannelBindRequest(TurnPort* port, TurnEntry* entry, int channel_id,
const rtc::SocketAddress& ext_addr);
void Prepare(StunMessage* request) override;
void OnSent() override;
void OnResponse(StunMessage* response) override;
void OnErrorResponse(StunMessage* response) override;
void OnTimeout() override;
private:
void OnEntryDestroyed(TurnEntry* entry);
TurnPort* port_;
TurnEntry* entry_;
int channel_id_;
rtc::SocketAddress ext_addr_;
};
// Manages a "connection" to a remote destination. We will attempt to bring up
// a channel for this remote destination to reduce the overhead of sending data.
class TurnEntry : public sigslot::has_slots<> {
public:
enum BindState { STATE_UNBOUND, STATE_BINDING, STATE_BOUND };
TurnEntry(TurnPort* port, int channel_id,
const rtc::SocketAddress& ext_addr);
TurnPort* port() { return port_; }
int channel_id() const { return channel_id_; }
const rtc::SocketAddress& address() const { return ext_addr_; }
BindState state() const { return state_; }
// Helper methods to send permission and channel bind requests.
void SendCreatePermissionRequest();
void SendChannelBindRequest(int delay);
// Sends a packet to the given destination address.
// This will wrap the packet in STUN if necessary.
int Send(const void* data, size_t size, bool payload,
const rtc::PacketOptions& options);
void OnCreatePermissionSuccess();
void OnCreatePermissionError(StunMessage* response, int code);
void OnChannelBindSuccess();
void OnChannelBindError(StunMessage* response, int code);
// Signal sent when TurnEntry is destroyed.
sigslot::signal1<TurnEntry*> SignalDestroyed;
private:
TurnPort* port_;
int channel_id_;
rtc::SocketAddress ext_addr_;
BindState state_;
};
TurnPort::TurnPort(rtc::Thread* thread,
rtc::PacketSocketFactory* factory,
rtc::Network* network,
rtc::AsyncPacketSocket* socket,
const std::string& username,
const std::string& password,
const ProtocolAddress& server_address,
const RelayCredentials& credentials,
int server_priority,
const std::string& origin)
: Port(thread,
factory,
network,
socket->GetLocalAddress().ipaddr(),
username,
password),
server_address_(server_address),
credentials_(credentials),
socket_(socket),
resolver_(NULL),
error_(0),
request_manager_(thread),
next_channel_number_(TURN_CHANNEL_NUMBER_START),
state_(STATE_CONNECTING),
server_priority_(server_priority),
allocate_mismatch_retries_(0) {
request_manager_.SignalSendPacket.connect(this, &TurnPort::OnSendStunPacket);
request_manager_.set_origin(origin);
}
TurnPort::TurnPort(rtc::Thread* thread,
rtc::PacketSocketFactory* factory,
rtc::Network* network,
const rtc::IPAddress& ip,
uint16 min_port,
uint16 max_port,
const std::string& username,
const std::string& password,
const ProtocolAddress& server_address,
const RelayCredentials& credentials,
int server_priority,
const std::string& origin)
: Port(thread,
RELAY_PORT_TYPE,
factory,
network,
ip,
min_port,
max_port,
username,
password),
server_address_(server_address),
credentials_(credentials),
socket_(NULL),
resolver_(NULL),
error_(0),
request_manager_(thread),
next_channel_number_(TURN_CHANNEL_NUMBER_START),
state_(STATE_CONNECTING),
server_priority_(server_priority),
allocate_mismatch_retries_(0) {
request_manager_.SignalSendPacket.connect(this, &TurnPort::OnSendStunPacket);
request_manager_.set_origin(origin);
}
TurnPort::~TurnPort() {
// TODO(juberti): Should this even be necessary?
// release the allocation by sending a refresh with
// lifetime 0.
if (ready()) {
TurnRefreshRequest bye(this);
bye.set_lifetime(0);
SendRequest(&bye, 0);
}
while (!entries_.empty()) {
DestroyEntry(entries_.front()->address());
}
if (resolver_) {
resolver_->Destroy(false);
}
if (!SharedSocket()) {
delete socket_;
}
}
rtc::SocketAddress TurnPort::GetLocalAddress() const {
return socket_ ? socket_->GetLocalAddress() : rtc::SocketAddress();
}
void TurnPort::PrepareAddress() {
if (credentials_.username.empty() ||
credentials_.password.empty()) {
LOG(LS_ERROR) << "Allocation can't be started without setting the"
<< " TURN server credentials for the user.";
OnAllocateError();
return;
}
if (!server_address_.address.port()) {
// We will set default TURN port, if no port is set in the address.
server_address_.address.SetPort(TURN_DEFAULT_PORT);
}
if (server_address_.address.IsUnresolved()) {
ResolveTurnAddress(server_address_.address);
} else {
// If protocol family of server address doesn't match with local, return.
if (!IsCompatibleAddress(server_address_.address)) {
LOG(LS_ERROR) << "IP address family does not match: "
<< "server: " << server_address_.address.family()
<< "local: " << ip().family();
OnAllocateError();
return;
}
// Insert the current address to prevent redirection pingpong.
attempted_server_addresses_.insert(server_address_.address);
LOG_J(LS_INFO, this) << "Trying to connect to TURN server via "
<< ProtoToString(server_address_.proto) << " @ "
<< server_address_.address.ToSensitiveString();
if (!CreateTurnClientSocket()) {
LOG(LS_ERROR) << "Failed to create TURN client socket";
OnAllocateError();
return;
}
if (server_address_.proto == PROTO_UDP) {
// If its UDP, send AllocateRequest now.
// For TCP and TLS AllcateRequest will be sent by OnSocketConnect.
SendRequest(new TurnAllocateRequest(this), 0);
}
}
}
bool TurnPort::CreateTurnClientSocket() {
ASSERT(!socket_ || SharedSocket());
if (server_address_.proto == PROTO_UDP && !SharedSocket()) {
socket_ = socket_factory()->CreateUdpSocket(
rtc::SocketAddress(ip(), 0), min_port(), max_port());
} else if (server_address_.proto == PROTO_TCP) {
ASSERT(!SharedSocket());
int opts = rtc::PacketSocketFactory::OPT_STUN;
// If secure bit is enabled in server address, use TLS over TCP.
if (server_address_.secure) {
opts |= rtc::PacketSocketFactory::OPT_TLS;
}
socket_ = socket_factory()->CreateClientTcpSocket(
rtc::SocketAddress(ip(), 0), server_address_.address,
proxy(), user_agent(), opts);
}
if (!socket_) {
error_ = SOCKET_ERROR;
return false;
}
// Apply options if any.
for (SocketOptionsMap::iterator iter = socket_options_.begin();
iter != socket_options_.end(); ++iter) {
socket_->SetOption(iter->first, iter->second);
}
if (!SharedSocket()) {
// If socket is shared, AllocationSequence will receive the packet.
socket_->SignalReadPacket.connect(this, &TurnPort::OnReadPacket);
}
socket_->SignalReadyToSend.connect(this, &TurnPort::OnReadyToSend);
// TCP port is ready to send stun requests after the socket is connected,
// while UDP port is ready to do so once the socket is created.
if (server_address_.proto == PROTO_TCP) {
socket_->SignalConnect.connect(this, &TurnPort::OnSocketConnect);
socket_->SignalClose.connect(this, &TurnPort::OnSocketClose);
} else {
state_ = STATE_CONNECTED;
}
return true;
}
void TurnPort::OnSocketConnect(rtc::AsyncPacketSocket* socket) {
ASSERT(server_address_.proto == PROTO_TCP);
// Do not use this port if the socket bound to a different address than
// the one we asked for. This is seen in Chrome, where TCP sockets cannot be
// given a binding address, and the platform is expected to pick the
// correct local address.
// However, there are two situations in which we allow the bound address to
// differ from the requested address: 1. The bound address is the loopback
// address. This happens when a proxy forces TCP to bind to only the
// localhost address (see issue 3927). 2. The bound address is the "any
// address". This happens when multiple_routes is disabled (see issue 4780).
if (socket->GetLocalAddress().ipaddr() != ip()) {
if (socket->GetLocalAddress().IsLoopbackIP()) {
LOG(LS_WARNING) << "Socket is bound to a different address:"
<< socket->GetLocalAddress().ipaddr().ToString()
<< ", rather then the local port:" << ip().ToString()
<< ". Still allowing it since it's localhost.";
} else if (IPIsAny(ip())) {
LOG(LS_WARNING) << "Socket is bound to a different address:"
<< socket->GetLocalAddress().ipaddr().ToString()
<< ", rather then the local port:" << ip().ToString()
<< ". Still allowing it since it's any address"
<< ", possibly caused by multiple_routes being disabled.";
} else {
LOG(LS_WARNING) << "Socket is bound to a different address:"
<< socket->GetLocalAddress().ipaddr().ToString()
<< ", rather then the local port:" << ip().ToString()
<< ". Discarding TURN port.";
OnAllocateError();
return;
}
}
state_ = STATE_CONNECTED; // It is ready to send stun requests.
if (server_address_.address.IsUnresolved()) {
server_address_.address = socket_->GetRemoteAddress();
}
LOG(LS_INFO) << "TurnPort connected to " << socket->GetRemoteAddress()
<< " using tcp.";
SendRequest(new TurnAllocateRequest(this), 0);
}
void TurnPort::OnSocketClose(rtc::AsyncPacketSocket* socket, int error) {
LOG_J(LS_WARNING, this) << "Connection with server failed, error=" << error;
ASSERT(socket == socket_);
if (!ready()) {
OnAllocateError();
}
request_manager_.Clear();
state_ = STATE_DISCONNECTED;
}
void TurnPort::OnAllocateMismatch() {
if (allocate_mismatch_retries_ >= MAX_ALLOCATE_MISMATCH_RETRIES) {
LOG_J(LS_WARNING, this) << "Giving up on the port after "
<< allocate_mismatch_retries_
<< " retries for STUN_ERROR_ALLOCATION_MISMATCH";
OnAllocateError();
return;
}
LOG_J(LS_INFO, this) << "Allocating a new socket after "
<< "STUN_ERROR_ALLOCATION_MISMATCH, retry = "
<< allocate_mismatch_retries_ + 1;
if (SharedSocket()) {
ResetSharedSocket();
} else {
delete socket_;
}
socket_ = NULL;
PrepareAddress();
++allocate_mismatch_retries_;
}
Connection* TurnPort::CreateConnection(const Candidate& address,
CandidateOrigin origin) {
// TURN-UDP can only connect to UDP candidates.
if (address.protocol() != UDP_PROTOCOL_NAME) {
return NULL;
}
if (!IsCompatibleAddress(address.address())) {
return NULL;
}
if (state_ == STATE_DISCONNECTED) {
return NULL;
}
// Create an entry, if needed, so we can get our permissions set up correctly.
CreateEntry(address.address());
// A TURN port will have two candiates, STUN and TURN. STUN may not
// present in all cases. If present stun candidate will be added first
// and TURN candidate later.
for (size_t index = 0; index < Candidates().size(); ++index) {
if (Candidates()[index].type() == RELAY_PORT_TYPE) {
ProxyConnection* conn = new ProxyConnection(this, index, address);
conn->SignalDestroyed.connect(this, &TurnPort::OnConnectionDestroyed);
AddConnection(conn);
return conn;
}
}
return NULL;
}
int TurnPort::SetOption(rtc::Socket::Option opt, int value) {
if (!socket_) {
// If socket is not created yet, these options will be applied during socket
// creation.
socket_options_[opt] = value;
return 0;
}
return socket_->SetOption(opt, value);
}
int TurnPort::GetOption(rtc::Socket::Option opt, int* value) {
if (!socket_) {
SocketOptionsMap::const_iterator it = socket_options_.find(opt);
if (it == socket_options_.end()) {
return -1;
}
*value = it->second;
return 0;
}
return socket_->GetOption(opt, value);
}
int TurnPort::GetError() {
return error_;
}
int TurnPort::SendTo(const void* data, size_t size,
const rtc::SocketAddress& addr,
const rtc::PacketOptions& options,
bool payload) {
// Try to find an entry for this specific address; we should have one.
TurnEntry* entry = FindEntry(addr);
if (!entry) {
LOG(LS_ERROR) << "Did not find the TurnEntry for address " << addr;
return 0;
}
if (!ready()) {
error_ = EWOULDBLOCK;
return SOCKET_ERROR;
}
// Send the actual contents to the server using the usual mechanism.
int sent = entry->Send(data, size, payload, options);
if (sent <= 0) {
return SOCKET_ERROR;
}
// The caller of the function is expecting the number of user data bytes,
// rather than the size of the packet.
return static_cast<int>(size);
}
void TurnPort::OnReadPacket(
rtc::AsyncPacketSocket* socket, const char* data, size_t size,
const rtc::SocketAddress& remote_addr,
const rtc::PacketTime& packet_time) {
ASSERT(socket == socket_);
// This is to guard against a STUN response from previous server after
// alternative server redirection. TODO(guoweis): add a unit test for this
// race condition.
if (remote_addr != server_address_.address) {
LOG_J(LS_WARNING, this) << "Discarding TURN message from unknown address:"
<< remote_addr.ToString()
<< ", server_address_:"
<< server_address_.address.ToString();
return;
}
// The message must be at least the size of a channel header.
if (size < TURN_CHANNEL_HEADER_SIZE) {
LOG_J(LS_WARNING, this) << "Received TURN message that was too short";
return;
}
// Check the message type, to see if is a Channel Data message.
// The message will either be channel data, a TURN data indication, or
// a response to a previous request.
uint16 msg_type = rtc::GetBE16(data);
if (IsTurnChannelData(msg_type)) {
HandleChannelData(msg_type, data, size, packet_time);
} else if (msg_type == TURN_DATA_INDICATION) {
HandleDataIndication(data, size, packet_time);
} else {
if (SharedSocket() &&
(msg_type == STUN_BINDING_RESPONSE ||
msg_type == STUN_BINDING_ERROR_RESPONSE)) {
LOG_J(LS_VERBOSE, this) <<
"Ignoring STUN binding response message on shared socket.";
return;
}
// This must be a response for one of our requests.
// Check success responses, but not errors, for MESSAGE-INTEGRITY.
if (IsStunSuccessResponseType(msg_type) &&
!StunMessage::ValidateMessageIntegrity(data, size, hash())) {
LOG_J(LS_WARNING, this) << "Received TURN message with invalid "
<< "message integrity, msg_type=" << msg_type;
return;
}
request_manager_.CheckResponse(data, size);
}
}
void TurnPort::OnReadyToSend(rtc::AsyncPacketSocket* socket) {
if (ready()) {
Port::OnReadyToSend();
}
}
// Update current server address port with the alternate server address port.
bool TurnPort::SetAlternateServer(const rtc::SocketAddress& address) {
// Check if we have seen this address before and reject if we did.
AttemptedServerSet::iterator iter = attempted_server_addresses_.find(address);
if (iter != attempted_server_addresses_.end()) {
LOG_J(LS_WARNING, this) << "Redirection to ["
<< address.ToSensitiveString()
<< "] ignored, allocation failed.";
return false;
}
// If protocol family of server address doesn't match with local, return.
if (!IsCompatibleAddress(address)) {
LOG(LS_WARNING) << "Server IP address family does not match with "
<< "local host address family type";
return false;
}
LOG_J(LS_INFO, this) << "Redirecting from TURN server ["
<< server_address_.address.ToSensitiveString()
<< "] to TURN server ["
<< address.ToSensitiveString()
<< "]";
server_address_ = ProtocolAddress(address, server_address_.proto,
server_address_.secure);
// Insert the current address to prevent redirection pingpong.
attempted_server_addresses_.insert(server_address_.address);
return true;
}
void TurnPort::ResolveTurnAddress(const rtc::SocketAddress& address) {
if (resolver_)
return;
resolver_ = socket_factory()->CreateAsyncResolver();
resolver_->SignalDone.connect(this, &TurnPort::OnResolveResult);
resolver_->Start(address);
}
void TurnPort::OnResolveResult(rtc::AsyncResolverInterface* resolver) {
ASSERT(resolver == resolver_);
// If DNS resolve is failed when trying to connect to the server using TCP,
// one of the reason could be due to DNS queries blocked by firewall.
// In such cases we will try to connect to the server with hostname, assuming
// socket layer will resolve the hostname through a HTTP proxy (if any).
if (resolver_->GetError() != 0 && server_address_.proto == PROTO_TCP) {
if (!CreateTurnClientSocket()) {
OnAllocateError();
}
return;
}
// Copy the original server address in |resolved_address|. For TLS based
// sockets we need hostname along with resolved address.
rtc::SocketAddress resolved_address = server_address_.address;
if (resolver_->GetError() != 0 ||
!resolver_->GetResolvedAddress(ip().family(), &resolved_address)) {
LOG_J(LS_WARNING, this) << "TURN host lookup received error "
<< resolver_->GetError();
error_ = resolver_->GetError();
OnAllocateError();
return;
}
// Signal needs both resolved and unresolved address. After signal is sent
// we can copy resolved address back into |server_address_|.
SignalResolvedServerAddress(this, server_address_.address,
resolved_address);
server_address_.address = resolved_address;
PrepareAddress();
}
void TurnPort::OnSendStunPacket(const void* data, size_t size,
StunRequest* request) {
ASSERT(connected());
rtc::PacketOptions options(DefaultDscpValue());
if (Send(data, size, options) < 0) {
LOG_J(LS_ERROR, this) << "Failed to send TURN message, err="
<< socket_->GetError();
}
}
void TurnPort::OnStunAddress(const rtc::SocketAddress& address) {
// STUN Port will discover STUN candidate, as it's supplied with first TURN
// server address.
// Why not using this address? - P2PTransportChannel will start creating
// connections after first candidate, which means it could start creating the
// connections before TURN candidate added. For that to handle, we need to
// supply STUN candidate from this port to UDPPort, and TurnPort should have
// handle to UDPPort to pass back the address.
}
void TurnPort::OnAllocateSuccess(const rtc::SocketAddress& address,
const rtc::SocketAddress& stun_address) {
state_ = STATE_READY;
rtc::SocketAddress related_address = stun_address;
if (!(candidate_filter() & CF_REFLEXIVE)) {
// If candidate filter only allows relay type of address, empty raddr to
// avoid local address leakage.
related_address = rtc::EmptySocketAddressWithFamily(stun_address.family());
}
// For relayed candidate, Base is the candidate itself.
AddAddress(address, // Candidate address.
address, // Base address.
related_address, // Related address.
UDP_PROTOCOL_NAME,
ProtoToString(server_address_.proto), // The first hop protocol.
"", // TCP canddiate type, empty for turn candidates.
RELAY_PORT_TYPE,
GetRelayPreference(server_address_.proto, server_address_.secure),
server_priority_, true);
}
void TurnPort::OnAllocateError() {
// We will send SignalPortError asynchronously as this can be sent during
// port initialization. This way it will not be blocking other port
// creation.
thread()->Post(this, MSG_ERROR);
}
void TurnPort::OnMessage(rtc::Message* message) {
if (message->message_id == MSG_ERROR) {
SignalPortError(this);
return;
} else if (message->message_id == MSG_ALLOCATE_MISMATCH) {
OnAllocateMismatch();
return;
} else if (message->message_id == MSG_TRY_ALTERNATE_SERVER) {
if (server_address().proto == PROTO_UDP) {
// Send another allocate request to alternate server, with the received
// realm and nonce values.
SendRequest(new TurnAllocateRequest(this), 0);
} else {
// Since it's TCP, we have to delete the connected socket and reconnect
// with the alternate server. PrepareAddress will send stun binding once
// the new socket is connected.
ASSERT(server_address().proto == PROTO_TCP);
ASSERT(!SharedSocket());
delete socket_;
socket_ = NULL;
PrepareAddress();
}
return;
}
Port::OnMessage(message);
}
void TurnPort::OnAllocateRequestTimeout() {
OnAllocateError();
}
void TurnPort::HandleDataIndication(const char* data, size_t size,
const rtc::PacketTime& packet_time) {
// Read in the message, and process according to RFC5766, Section 10.4.
rtc::ByteBuffer buf(data, size);
TurnMessage msg;
if (!msg.Read(&buf)) {
LOG_J(LS_WARNING, this) << "Received invalid TURN data indication";
return;
}
// Check mandatory attributes.
const StunAddressAttribute* addr_attr =
msg.GetAddress(STUN_ATTR_XOR_PEER_ADDRESS);
if (!addr_attr) {
LOG_J(LS_WARNING, this) << "Missing STUN_ATTR_XOR_PEER_ADDRESS attribute "
<< "in data indication.";
return;
}
const StunByteStringAttribute* data_attr =
msg.GetByteString(STUN_ATTR_DATA);
if (!data_attr) {
LOG_J(LS_WARNING, this) << "Missing STUN_ATTR_DATA attribute in "
<< "data indication.";
return;
}
// Verify that the data came from somewhere we think we have a permission for.
rtc::SocketAddress ext_addr(addr_attr->GetAddress());
if (!HasPermission(ext_addr.ipaddr())) {
LOG_J(LS_WARNING, this) << "Received TURN data indication with invalid "
<< "peer address, addr="
<< ext_addr.ToSensitiveString();
return;
}
DispatchPacket(data_attr->bytes(), data_attr->length(), ext_addr,
PROTO_UDP, packet_time);
}
void TurnPort::HandleChannelData(int channel_id, const char* data,
size_t size,
const rtc::PacketTime& packet_time) {
// Read the message, and process according to RFC5766, Section 11.6.
// 0 1 2 3
// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// | Channel Number | Length |
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// | |
// / Application Data /
// / /
// | |
// | +-------------------------------+
// | |
// +-------------------------------+
// Extract header fields from the message.
uint16 len = rtc::GetBE16(data + 2);
if (len > size - TURN_CHANNEL_HEADER_SIZE) {
LOG_J(LS_WARNING, this) << "Received TURN channel data message with "
<< "incorrect length, len=" << len;
return;
}
// Allowing messages larger than |len|, as ChannelData can be padded.
TurnEntry* entry = FindEntry(channel_id);
if (!entry) {
LOG_J(LS_WARNING, this) << "Received TURN channel data message for invalid "
<< "channel, channel_id=" << channel_id;
return;
}
DispatchPacket(data + TURN_CHANNEL_HEADER_SIZE, len, entry->address(),
PROTO_UDP, packet_time);
}
void TurnPort::DispatchPacket(const char* data, size_t size,
const rtc::SocketAddress& remote_addr,
ProtocolType proto, const rtc::PacketTime& packet_time) {
if (Connection* conn = GetConnection(remote_addr)) {
conn->OnReadPacket(data, size, packet_time);
} else {
Port::OnReadPacket(data, size, remote_addr, proto);
}
}
bool TurnPort::ScheduleRefresh(int lifetime) {
// Lifetime is in seconds; we schedule a refresh for one minute less.
if (lifetime < 2 * 60) {
LOG_J(LS_WARNING, this) << "Received response with lifetime that was "
<< "too short, lifetime=" << lifetime;
return false;
}
int delay = (lifetime - 60) * 1000;
SendRequest(new TurnRefreshRequest(this), delay);
LOG_J(LS_INFO, this) << "Scheduled refresh in " << delay << "ms.";
return true;
}
void TurnPort::SendRequest(StunRequest* req, int delay) {
request_manager_.SendDelayed(req, delay);
}
void TurnPort::AddRequestAuthInfo(StunMessage* msg) {
// If we've gotten the necessary data from the server, add it to our request.
VERIFY(!hash_.empty());
VERIFY(msg->AddAttribute(new StunByteStringAttribute(
STUN_ATTR_USERNAME, credentials_.username)));
VERIFY(msg->AddAttribute(new StunByteStringAttribute(
STUN_ATTR_REALM, realm_)));
VERIFY(msg->AddAttribute(new StunByteStringAttribute(
STUN_ATTR_NONCE, nonce_)));
VERIFY(msg->AddMessageIntegrity(hash()));
}
int TurnPort::Send(const void* data, size_t len,
const rtc::PacketOptions& options) {
return socket_->SendTo(data, len, server_address_.address, options);
}
void TurnPort::UpdateHash() {
VERIFY(ComputeStunCredentialHash(credentials_.username, realm_,
credentials_.password, &hash_));
}
bool TurnPort::UpdateNonce(StunMessage* response) {
// When stale nonce error received, we should update
// hash and store realm and nonce.
// Check the mandatory attributes.
const StunByteStringAttribute* realm_attr =
response->GetByteString(STUN_ATTR_REALM);
if (!realm_attr) {
LOG(LS_ERROR) << "Missing STUN_ATTR_REALM attribute in "
<< "stale nonce error response.";
return false;
}
set_realm(realm_attr->GetString());
const StunByteStringAttribute* nonce_attr =
response->GetByteString(STUN_ATTR_NONCE);
if (!nonce_attr) {
LOG(LS_ERROR) << "Missing STUN_ATTR_NONCE attribute in "
<< "stale nonce error response.";
return false;
}
set_nonce(nonce_attr->GetString());
return true;
}
static bool MatchesIP(TurnEntry* e, rtc::IPAddress ipaddr) {
return e->address().ipaddr() == ipaddr;
}
bool TurnPort::HasPermission(const rtc::IPAddress& ipaddr) const {
return (std::find_if(entries_.begin(), entries_.end(),
std::bind2nd(std::ptr_fun(MatchesIP), ipaddr)) != entries_.end());
}
static bool MatchesAddress(TurnEntry* e, rtc::SocketAddress addr) {
return e->address() == addr;
}
TurnEntry* TurnPort::FindEntry(const rtc::SocketAddress& addr) const {
EntryList::const_iterator it = std::find_if(entries_.begin(), entries_.end(),
std::bind2nd(std::ptr_fun(MatchesAddress), addr));
return (it != entries_.end()) ? *it : NULL;
}
static bool MatchesChannelId(TurnEntry* e, int id) {
return e->channel_id() == id;
}
TurnEntry* TurnPort::FindEntry(int channel_id) const {
EntryList::const_iterator it = std::find_if(entries_.begin(), entries_.end(),
std::bind2nd(std::ptr_fun(MatchesChannelId), channel_id));
return (it != entries_.end()) ? *it : NULL;
}
TurnEntry* TurnPort::CreateEntry(const rtc::SocketAddress& addr) {
ASSERT(FindEntry(addr) == NULL);
TurnEntry* entry = new TurnEntry(this, next_channel_number_++, addr);
entries_.push_back(entry);
return entry;
}
void TurnPort::DestroyEntry(const rtc::SocketAddress& addr) {
TurnEntry* entry = FindEntry(addr);
ASSERT(entry != NULL);
entry->SignalDestroyed(entry);
entries_.remove(entry);
delete entry;
}
void TurnPort::OnConnectionDestroyed(Connection* conn) {
// Destroying TurnEntry for the connection, which is already destroyed.
DestroyEntry(conn->remote_candidate().address());
}
TurnAllocateRequest::TurnAllocateRequest(TurnPort* port)
: StunRequest(new TurnMessage()),
port_(port) {
}
void TurnAllocateRequest::Prepare(StunMessage* request) {
// Create the request as indicated in RFC 5766, Section 6.1.
request->SetType(TURN_ALLOCATE_REQUEST);
StunUInt32Attribute* transport_attr = StunAttribute::CreateUInt32(
STUN_ATTR_REQUESTED_TRANSPORT);
transport_attr->SetValue(IPPROTO_UDP << 24);
VERIFY(request->AddAttribute(transport_attr));
if (!port_->hash().empty()) {
port_->AddRequestAuthInfo(request);
}
}
void TurnAllocateRequest::OnSent() {
LOG_J(LS_INFO, port_) << "TURN allocate request sent"
<< ", id=" << rtc::hex_encode(id());
StunRequest::OnSent();
}
void TurnAllocateRequest::OnResponse(StunMessage* response) {
LOG_J(LS_INFO, port_) << "TURN allocate requested successfully"
<< ", id=" << rtc::hex_encode(id())
<< ", code=0" // Makes logging easier to parse.
<< ", rtt=" << Elapsed();
// Check mandatory attributes as indicated in RFC5766, Section 6.3.
const StunAddressAttribute* mapped_attr =
response->GetAddress(STUN_ATTR_XOR_MAPPED_ADDRESS);
if (!mapped_attr) {
LOG_J(LS_WARNING, port_) << "Missing STUN_ATTR_XOR_MAPPED_ADDRESS "
<< "attribute in allocate success response";
return;
}
// Using XOR-Mapped-Address for stun.
port_->OnStunAddress(mapped_attr->GetAddress());
const StunAddressAttribute* relayed_attr =
response->GetAddress(STUN_ATTR_XOR_RELAYED_ADDRESS);
if (!relayed_attr) {
LOG_J(LS_WARNING, port_) << "Missing STUN_ATTR_XOR_RELAYED_ADDRESS "
<< "attribute in allocate success response";
return;
}
const StunUInt32Attribute* lifetime_attr =
response->GetUInt32(STUN_ATTR_TURN_LIFETIME);
if (!lifetime_attr) {
LOG_J(LS_WARNING, port_) << "Missing STUN_ATTR_TURN_LIFETIME attribute in "
<< "allocate success response";
return;
}
// Notify the port the allocate succeeded, and schedule a refresh request.
port_->OnAllocateSuccess(relayed_attr->GetAddress(),
mapped_attr->GetAddress());
port_->ScheduleRefresh(lifetime_attr->value());
}
void TurnAllocateRequest::OnErrorResponse(StunMessage* response) {
// Process error response according to RFC5766, Section 6.4.
const StunErrorCodeAttribute* error_code = response->GetErrorCode();
LOG_J(LS_INFO, port_) << "Received TURN allocate error response"
<< ", id=" << rtc::hex_encode(id())
<< ", code=" << error_code->code()
<< ", rtt=" << Elapsed();
switch (error_code->code()) {
case STUN_ERROR_UNAUTHORIZED: // Unauthrorized.
OnAuthChallenge(response, error_code->code());
break;
case STUN_ERROR_TRY_ALTERNATE:
OnTryAlternate(response, error_code->code());
break;
case STUN_ERROR_ALLOCATION_MISMATCH:
// We must handle this error async because trying to delete the socket in
// OnErrorResponse will cause a deadlock on the socket.
port_->thread()->Post(port_, TurnPort::MSG_ALLOCATE_MISMATCH);
break;
default:
LOG_J(LS_WARNING, port_) << "Received TURN allocate error response"
<< ", id=" << rtc::hex_encode(id())
<< ", code=" << error_code->code()
<< ", rtt=" << Elapsed();
port_->OnAllocateError();
}
}
void TurnAllocateRequest::OnTimeout() {
LOG_J(LS_WARNING, port_) << "TURN allocate request "
<< rtc::hex_encode(id()) << " timout";
port_->OnAllocateRequestTimeout();
}
void TurnAllocateRequest::OnAuthChallenge(StunMessage* response, int code) {
// If we failed to authenticate even after we sent our credentials, fail hard.
if (code == STUN_ERROR_UNAUTHORIZED && !port_->hash().empty()) {
LOG_J(LS_WARNING, port_) << "Failed to authenticate with the server "
<< "after challenge.";
port_->OnAllocateError();
return;
}
// Check the mandatory attributes.
const StunByteStringAttribute* realm_attr =
response->GetByteString(STUN_ATTR_REALM);
if (!realm_attr) {
LOG_J(LS_WARNING, port_) << "Missing STUN_ATTR_REALM attribute in "
<< "allocate unauthorized response.";
return;
}
port_->set_realm(realm_attr->GetString());
const StunByteStringAttribute* nonce_attr =
response->GetByteString(STUN_ATTR_NONCE);
if (!nonce_attr) {
LOG_J(LS_WARNING, port_) << "Missing STUN_ATTR_NONCE attribute in "
<< "allocate unauthorized response.";
return;
}
port_->set_nonce(nonce_attr->GetString());
// Send another allocate request, with the received realm and nonce values.
port_->SendRequest(new TurnAllocateRequest(port_), 0);
}
void TurnAllocateRequest::OnTryAlternate(StunMessage* response, int code) {
// According to RFC 5389 section 11, there are use cases where
// authentication of response is not possible, we're not validating
// message integrity.
// Get the alternate server address attribute value.
const StunAddressAttribute* alternate_server_attr =
response->GetAddress(STUN_ATTR_ALTERNATE_SERVER);
if (!alternate_server_attr) {
LOG_J(LS_WARNING, port_) << "Missing STUN_ATTR_ALTERNATE_SERVER "
<< "attribute in try alternate error response";
port_->OnAllocateError();
return;
}
if (!port_->SetAlternateServer(alternate_server_attr->GetAddress())) {
port_->OnAllocateError();
return;
}
// Check the attributes.
const StunByteStringAttribute* realm_attr =
response->GetByteString(STUN_ATTR_REALM);
if (realm_attr) {
LOG_J(LS_INFO, port_) << "Applying STUN_ATTR_REALM attribute in "
<< "try alternate error response.";
port_->set_realm(realm_attr->GetString());
}
const StunByteStringAttribute* nonce_attr =
response->GetByteString(STUN_ATTR_NONCE);
if (nonce_attr) {
LOG_J(LS_INFO, port_) << "Applying STUN_ATTR_NONCE attribute in "
<< "try alternate error response.";
port_->set_nonce(nonce_attr->GetString());
}
// For TCP, we can't close the original Tcp socket during handling a 300 as
// we're still inside that socket's event handler. Doing so will cause
// deadlock.
port_->thread()->Post(port_, TurnPort::MSG_TRY_ALTERNATE_SERVER);
}
TurnRefreshRequest::TurnRefreshRequest(TurnPort* port)
: StunRequest(new TurnMessage()),
port_(port),
lifetime_(-1) {
}
void TurnRefreshRequest::Prepare(StunMessage* request) {
// Create the request as indicated in RFC 5766, Section 7.1.
// No attributes need to be included.
request->SetType(TURN_REFRESH_REQUEST);
if (lifetime_ > -1) {
VERIFY(request->AddAttribute(new StunUInt32Attribute(
STUN_ATTR_LIFETIME, lifetime_)));
}
port_->AddRequestAuthInfo(request);
}
void TurnRefreshRequest::OnSent() {
LOG_J(LS_INFO, port_) << "TURN refresh request sent"
<< ", id=" << rtc::hex_encode(id());
StunRequest::OnSent();
}
void TurnRefreshRequest::OnResponse(StunMessage* response) {
LOG_J(LS_INFO, port_) << "TURN refresh requested successfully"
<< ", id=" << rtc::hex_encode(id())
<< ", code=0" // Makes logging easier to parse.
<< ", rtt=" << Elapsed();
// Check mandatory attributes as indicated in RFC5766, Section 7.3.
const StunUInt32Attribute* lifetime_attr =
response->GetUInt32(STUN_ATTR_TURN_LIFETIME);
if (!lifetime_attr) {
LOG_J(LS_WARNING, port_) << "Missing STUN_ATTR_TURN_LIFETIME attribute in "
<< "refresh success response.";
return;
}
// Schedule a refresh based on the returned lifetime value.
port_->ScheduleRefresh(lifetime_attr->value());
}
void TurnRefreshRequest::OnErrorResponse(StunMessage* response) {
const StunErrorCodeAttribute* error_code = response->GetErrorCode();
LOG_J(LS_INFO, port_) << "Received TURN refresh error response"
<< ", id=" << rtc::hex_encode(id())
<< ", code=" << error_code->code()
<< ", rtt=" << Elapsed();
if (error_code->code() == STUN_ERROR_STALE_NONCE) {
if (port_->UpdateNonce(response)) {
// Send RefreshRequest immediately.
port_->SendRequest(new TurnRefreshRequest(port_), 0);
}
} else {
LOG_J(LS_WARNING, port_) << "Received TURN refresh error response"
<< ", id=" << rtc::hex_encode(id())
<< ", code=" << error_code->code()
<< ", rtt=" << Elapsed();
}
}
void TurnRefreshRequest::OnTimeout() {
LOG_J(LS_WARNING, port_) << "TURN refresh timeout " << rtc::hex_encode(id());
}
TurnCreatePermissionRequest::TurnCreatePermissionRequest(
TurnPort* port, TurnEntry* entry,
const rtc::SocketAddress& ext_addr)
: StunRequest(new TurnMessage()),
port_(port),
entry_(entry),
ext_addr_(ext_addr) {
entry_->SignalDestroyed.connect(
this, &TurnCreatePermissionRequest::OnEntryDestroyed);
}
void TurnCreatePermissionRequest::Prepare(StunMessage* request) {
// Create the request as indicated in RFC5766, Section 9.1.
request->SetType(TURN_CREATE_PERMISSION_REQUEST);
VERIFY(request->AddAttribute(new StunXorAddressAttribute(
STUN_ATTR_XOR_PEER_ADDRESS, ext_addr_)));
port_->AddRequestAuthInfo(request);
}
void TurnCreatePermissionRequest::OnSent() {
LOG_J(LS_INFO, port_) << "TURN create permission request sent"
<< ", id=" << rtc::hex_encode(id());
StunRequest::OnSent();
}
void TurnCreatePermissionRequest::OnResponse(StunMessage* response) {
LOG_J(LS_INFO, port_) << "TURN permission requested successfully"
<< ", id=" << rtc::hex_encode(id())
<< ", code=0" // Makes logging easier to parse.
<< ", rtt=" << Elapsed();
if (entry_) {
entry_->OnCreatePermissionSuccess();
}
}
void TurnCreatePermissionRequest::OnErrorResponse(StunMessage* response) {
const StunErrorCodeAttribute* error_code = response->GetErrorCode();
LOG_J(LS_WARNING, port_) << "Received TURN create permission error response"
<< ", id=" << rtc::hex_encode(id())
<< ", code=" << error_code->code()
<< ", rtt=" << Elapsed();
if (entry_) {
entry_->OnCreatePermissionError(response, error_code->code());
}
}
void TurnCreatePermissionRequest::OnTimeout() {
LOG_J(LS_WARNING, port_) << "TURN create permission timeout "
<< rtc::hex_encode(id());
}
void TurnCreatePermissionRequest::OnEntryDestroyed(TurnEntry* entry) {
ASSERT(entry_ == entry);
entry_ = NULL;
}
TurnChannelBindRequest::TurnChannelBindRequest(
TurnPort* port, TurnEntry* entry,
int channel_id, const rtc::SocketAddress& ext_addr)
: StunRequest(new TurnMessage()),
port_(port),
entry_(entry),
channel_id_(channel_id),
ext_addr_(ext_addr) {
entry_->SignalDestroyed.connect(
this, &TurnChannelBindRequest::OnEntryDestroyed);
}
void TurnChannelBindRequest::Prepare(StunMessage* request) {
// Create the request as indicated in RFC5766, Section 11.1.
request->SetType(TURN_CHANNEL_BIND_REQUEST);
VERIFY(request->AddAttribute(new StunUInt32Attribute(
STUN_ATTR_CHANNEL_NUMBER, channel_id_ << 16)));
VERIFY(request->AddAttribute(new StunXorAddressAttribute(
STUN_ATTR_XOR_PEER_ADDRESS, ext_addr_)));
port_->AddRequestAuthInfo(request);
}
void TurnChannelBindRequest::OnSent() {
LOG_J(LS_INFO, port_) << "TURN channel bind request sent"
<< ", id=" << rtc::hex_encode(id());
StunRequest::OnSent();
}
void TurnChannelBindRequest::OnResponse(StunMessage* response) {
LOG_J(LS_INFO, port_) << "TURN channel bind requested successfully"
<< ", id=" << rtc::hex_encode(id())
<< ", code=0" // Makes logging easier to parse.
<< ", rtt=" << Elapsed();
if (entry_) {
entry_->OnChannelBindSuccess();
// Refresh the channel binding just under the permission timeout
// threshold. The channel binding has a longer lifetime, but
// this is the easiest way to keep both the channel and the
// permission from expiring.
int delay = TURN_PERMISSION_TIMEOUT - 60000;
entry_->SendChannelBindRequest(delay);
LOG_J(LS_INFO, port_) << "Scheduled channel bind in " << delay << "ms.";
}
}
void TurnChannelBindRequest::OnErrorResponse(StunMessage* response) {
const StunErrorCodeAttribute* error_code = response->GetErrorCode();
LOG_J(LS_WARNING, port_) << "Received TURN channel bind error response"
<< ", id=" << rtc::hex_encode(id())
<< ", code=" << error_code->code()
<< ", rtt=" << Elapsed();
if (entry_) {
entry_->OnChannelBindError(response, error_code->code());
}
}
void TurnChannelBindRequest::OnTimeout() {
LOG_J(LS_WARNING, port_) << "TURN channel bind timeout "
<< rtc::hex_encode(id());
}
void TurnChannelBindRequest::OnEntryDestroyed(TurnEntry* entry) {
ASSERT(entry_ == entry);
entry_ = NULL;
}
TurnEntry::TurnEntry(TurnPort* port, int channel_id,
const rtc::SocketAddress& ext_addr)
: port_(port),
channel_id_(channel_id),
ext_addr_(ext_addr),
state_(STATE_UNBOUND) {
// Creating permission for |ext_addr_|.
SendCreatePermissionRequest();
}
void TurnEntry::SendCreatePermissionRequest() {
port_->SendRequest(new TurnCreatePermissionRequest(
port_, this, ext_addr_), 0);
}
void TurnEntry::SendChannelBindRequest(int delay) {
port_->SendRequest(new TurnChannelBindRequest(
port_, this, channel_id_, ext_addr_), delay);
}
int TurnEntry::Send(const void* data, size_t size, bool payload,
const rtc::PacketOptions& options) {
rtc::ByteBuffer buf;
if (state_ != STATE_BOUND) {
// If we haven't bound the channel yet, we have to use a Send Indication.
TurnMessage msg;
msg.SetType(TURN_SEND_INDICATION);
msg.SetTransactionID(
rtc::CreateRandomString(kStunTransactionIdLength));
VERIFY(msg.AddAttribute(new StunXorAddressAttribute(
STUN_ATTR_XOR_PEER_ADDRESS, ext_addr_)));
VERIFY(msg.AddAttribute(new StunByteStringAttribute(
STUN_ATTR_DATA, data, size)));
VERIFY(msg.Write(&buf));
// If we're sending real data, request a channel bind that we can use later.
if (state_ == STATE_UNBOUND && payload) {
SendChannelBindRequest(0);
state_ = STATE_BINDING;
}
} else {
// If the channel is bound, we can send the data as a Channel Message.
buf.WriteUInt16(channel_id_);
buf.WriteUInt16(static_cast<uint16>(size));
buf.WriteBytes(reinterpret_cast<const char*>(data), size);
}
return port_->Send(buf.Data(), buf.Length(), options);
}
void TurnEntry::OnCreatePermissionSuccess() {
LOG_J(LS_INFO, port_) << "Create permission for "
<< ext_addr_.ToSensitiveString()
<< " succeeded";
// For success result code will be 0.
port_->SignalCreatePermissionResult(port_, ext_addr_, 0);
}
void TurnEntry::OnCreatePermissionError(StunMessage* response, int code) {
if (code == STUN_ERROR_STALE_NONCE) {
if (port_->UpdateNonce(response)) {
SendCreatePermissionRequest();
}
} else {
// Send signal with error code.
port_->SignalCreatePermissionResult(port_, ext_addr_, code);
}
}
void TurnEntry::OnChannelBindSuccess() {
LOG_J(LS_INFO, port_) << "Channel bind for " << ext_addr_.ToSensitiveString()
<< " succeeded";
ASSERT(state_ == STATE_BINDING || state_ == STATE_BOUND);
state_ = STATE_BOUND;
}
void TurnEntry::OnChannelBindError(StunMessage* response, int code) {
// TODO(mallinath) - Implement handling of error response for channel
// bind request as per http://tools.ietf.org/html/rfc5766#section-11.3
if (code == STUN_ERROR_STALE_NONCE) {
if (port_->UpdateNonce(response)) {
// Send channel bind request with fresh nonce.
SendChannelBindRequest(0);
}
}
}
} // namespace cricket