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#include "node_quic_socket-inl.h" // NOLINT(build/include)
#include "aliased_struct-inl.h"
#include "allocated_buffer-inl.h"
#include "async_wrap-inl.h"
#include "debug_utils-inl.h"
#include "env-inl.h"
#include "memory_tracker-inl.h"
#include "nghttp2/nghttp2.h"
#include "nghttp3/nghttp3.h"
#include "node.h"
#include "node_buffer.h"
#include "node_crypto.h"
#include "node_internals.h"
#include "node_mem-inl.h"
#include "node_quic_crypto.h"
#include "node_quic_session-inl.h"
#include "node_quic_util-inl.h"
#include "node_sockaddr-inl.h"
#include "req_wrap-inl.h"
#include "util.h"
#include "uv.h"
#include "v8.h"
#include <random>
namespace node {
using crypto::EntropySource;
using crypto::SecureContext;
using v8::ArrayBufferView;
using v8::Context;
using v8::FunctionCallbackInfo;
using v8::FunctionTemplate;
using v8::HandleScope;
using v8::Isolate;
using v8::Local;
using v8::Number;
using v8::Object;
using v8::ObjectTemplate;
using v8::PropertyAttribute;
using v8::String;
using v8::Value;
namespace quic {
namespace {
// The reserved version is a mechanism QUIC endpoints
// can use to ensure correct handling of version
// negotiation. It is defined by the QUIC spec in
// https://tools.ietf.org/html/draft-ietf-quic-transport-24#section-6.3
// Specifically, any version that follows the pattern
// 0x?a?a?a?a may be used to force version negotiation.
inline uint32_t GenerateReservedVersion(
const SocketAddress& addr,
uint32_t version) {
socklen_t addrlen = addr.length();
uint32_t h = 0x811C9DC5u;
const uint8_t* p = addr.raw();
const uint8_t* ep = p + addrlen;
for (; p != ep; ++p) {
h ^= *p;
h *= 0x01000193u;
}
version = htonl(version);
p = reinterpret_cast<const uint8_t*>(&version);
ep = p + sizeof(version);
for (; p != ep; ++p) {
h ^= *p;
h *= 0x01000193u;
}
h &= 0xf0f0f0f0u;
h |= 0x0a0a0a0au;
return h;
}
bool IsShortHeader(
uint32_t version,
const uint8_t* pscid,
size_t pscidlen) {
return version == NGTCP2_PROTO_VER &&
pscid == nullptr &&
pscidlen == 0;
}
} // namespace
QuicPacket::QuicPacket(const char* diagnostic_label, size_t len)
: data_{0},
len_(len),
diagnostic_label_(diagnostic_label) {
CHECK_LE(len, MAX_PKTLEN);
}
QuicPacket::QuicPacket(const QuicPacket& other) :
QuicPacket(other.diagnostic_label_, other.len_) {
memcpy(&data_, &other.data_, other.len_);
}
const char* QuicPacket::diagnostic_label() const {
return diagnostic_label_ != nullptr ?
diagnostic_label_ : "unspecified";
}
QuicSocketListener::~QuicSocketListener() {
if (socket_)
socket_->RemoveListener(this);
}
void QuicSocketListener::OnError(ssize_t code) {
if (previous_listener_ != nullptr)
previous_listener_->OnError(code);
}
void QuicSocketListener::OnSessionReady(BaseObjectPtr<QuicSession> session) {
if (previous_listener_ != nullptr)
previous_listener_->OnSessionReady(session);
}
void QuicSocketListener::OnServerBusy() {
if (previous_listener_ != nullptr)
previous_listener_->OnServerBusy();
}
void QuicSocketListener::OnEndpointDone(QuicEndpoint* endpoint) {
if (previous_listener_ != nullptr)
previous_listener_->OnEndpointDone(endpoint);
}
void QuicSocketListener::OnDestroy() {
if (previous_listener_ != nullptr)
previous_listener_->OnDestroy();
}
void JSQuicSocketListener::OnError(ssize_t code) {
Environment* env = socket()->env();
HandleScope scope(env->isolate());
Context::Scope context_scope(env->context());
Local<Value> arg = Number::New(env->isolate(), static_cast<double>(code));
socket()->MakeCallback(env->quic_on_socket_close_function(), 1, &arg);
}
void JSQuicSocketListener::OnSessionReady(BaseObjectPtr<QuicSession> session) {
Environment* env = socket()->env();
Local<Value> arg = session->object();
Context::Scope context_scope(env->context());
socket()->MakeCallback(env->quic_on_session_ready_function(), 1, &arg);
}
void JSQuicSocketListener::OnServerBusy() {
Environment* env = socket()->env();
HandleScope handle_scope(env->isolate());
Context::Scope context_scope(env->context());
socket()->MakeCallback(
env->quic_on_socket_server_busy_function(), 0, nullptr);
}
void JSQuicSocketListener::OnEndpointDone(QuicEndpoint* endpoint) {
Environment* env = socket()->env();
HandleScope scope(env->isolate());
Context::Scope context_scope(env->context());
MakeCallback(
env->isolate(),
endpoint->object(),
env->ondone_string(),
0, nullptr);
}
void JSQuicSocketListener::OnDestroy() {
// Do nothing here.
}
QuicEndpoint::QuicEndpoint(
QuicState* quic_state,
Local<Object> wrap,
QuicSocket* listener,
Local<Object> udp_wrap)
: BaseObject(quic_state->env(), wrap),
listener_(listener),
quic_state_(quic_state) {
MakeWeak();
udp_ = static_cast<UDPWrapBase*>(
udp_wrap->GetAlignedPointerFromInternalField(
UDPWrapBase::kUDPWrapBaseField));
CHECK_NOT_NULL(udp_);
udp_->set_listener(this);
strong_ptr_.reset(udp_->GetAsyncWrap());
}
QuicEndpoint::~QuicEndpoint() {
udp_->set_listener(nullptr);
}
uv_buf_t QuicEndpoint::OnAlloc(size_t suggested_size) {
return AllocatedBuffer::AllocateManaged(env(), suggested_size).release();
}
void QuicEndpoint::OnRecv(
ssize_t nread,
const uv_buf_t& buf_,
const sockaddr* addr,
unsigned int flags) {
AllocatedBuffer buf(env(), buf_);
if (nread <= 0) {
if (nread < 0)
listener_->OnError(this, nread);
return;
}
listener_->OnReceive(
nread,
std::move(buf),
local_address(),
SocketAddress(addr),
flags);
}
ReqWrap<uv_udp_send_t>* QuicEndpoint::CreateSendWrap(size_t msg_size) {
return listener_->OnCreateSendWrap(msg_size);
}
void QuicEndpoint::OnSendDone(ReqWrap<uv_udp_send_t>* wrap, int status) {
DecrementPendingCallbacks();
listener_->OnSendDone(wrap, status);
if (!has_pending_callbacks() && waiting_for_callbacks_)
listener_->OnEndpointDone(this);
}
void QuicEndpoint::OnAfterBind() {
listener_->OnBind(this);
}
template <typename Fn>
void QuicSocketStatsTraits::ToString(const QuicSocket& ptr, Fn&& add_field) {
#define V(_n, name, label) \
add_field(label, ptr.GetStat(&QuicSocketStats::name));
SOCKET_STATS(V)
#undef V
}
QuicSocket::QuicSocket(
QuicState* quic_state,
Local<Object> wrap,
uint64_t retry_token_expiration,
size_t max_connections,
size_t max_connections_per_host,
size_t max_stateless_resets_per_host,
uint32_t options,
QlogMode qlog,
const uint8_t* session_reset_secret,
bool disable_stateless_reset)
: AsyncWrap(quic_state->env(), wrap, AsyncWrap::PROVIDER_QUICSOCKET),
StatsBase(quic_state->env(), wrap),
alloc_info_(MakeAllocator()),
block_list_(SocketAddressBlockListWrap::New(quic_state->env())),
options_(options),
state_(quic_state->env()->isolate()),
max_connections_(max_connections),
max_connections_per_host_(max_connections_per_host),
max_stateless_resets_per_host_(max_stateless_resets_per_host),
retry_token_expiration_(retry_token_expiration),
qlog_(qlog),
server_alpn_(NGHTTP3_ALPN_H3),
addrLRU_(DEFAULT_MAX_SOCKETADDRESS_LRU_SIZE),
quic_state_(quic_state) {
MakeWeak();
PushListener(&default_listener_);
Debug(this, "New QuicSocket created");
EntropySource(token_secret_, kTokenSecretLen);
wrap->DefineOwnProperty(
env()->context(),
env()->block_list_string(),
block_list_->object(),
PropertyAttribute::ReadOnly).Check();
wrap->DefineOwnProperty(
env()->context(),
env()->state_string(),
state_.GetArrayBuffer(),
PropertyAttribute::ReadOnly).Check();
if (disable_stateless_reset)
state_->stateless_reset_disabled = 1;
// Set the session reset secret to the one provided or random.
// Note that a random secret is going to make it exceedingly
// difficult for the session reset token to be useful.
if (session_reset_secret != nullptr) {
memcpy(reset_token_secret_,
session_reset_secret,
NGTCP2_STATELESS_RESET_TOKENLEN);
} else {
EntropySource(reset_token_secret_, NGTCP2_STATELESS_RESET_TOKENLEN);
}
}
QuicSocket::~QuicSocket() {
QuicSocketListener* listener = listener_;
listener_->OnDestroy();
if (listener == listener_)
RemoveListener(listener_);
// In a clean shutdown, all QuicSessions associated with the QuicSocket
// would have been destroyed explicitly. However, if the QuicSocket is
// garbage collected / freed before Destroy having been called, there
// may be sessions remaining. This is not really a good thing.
Debug(this, "Destroying with %d sessions remaining", sessions_.size());
DebugStats();
}
void QuicSocket::MemoryInfo(MemoryTracker* tracker) const {
tracker->TrackField("endpoints", endpoints_);
tracker->TrackField("sessions", sessions_);
tracker->TrackField("dcid_to_scid", dcid_to_scid_);
tracker->TrackField("address_counts", addrLRU_);
tracker->TrackField("token_map", token_map_);
StatsBase::StatsMemoryInfo(tracker);
tracker->TrackFieldWithSize(
"current_ngtcp2_memory",
current_ngtcp2_memory_);
}
void QuicSocket::Listen(
BaseObjectPtr<SecureContext> sc,
const sockaddr* preferred_address,
const std::string& alpn,
uint32_t options) {
CHECK(sc);
CHECK_NE(state_->server_listening, 1);
Debug(this, "Starting to listen");
server_session_config_.Set(quic_state(), preferred_address);
server_secure_context_ = sc;
server_alpn_ = alpn;
server_options_ = options;
state_->server_listening = 1;
RecordTimestamp(&QuicSocketStats::listen_at);
ReceiveStart();
}
void QuicSocket::OnError(QuicEndpoint* endpoint, ssize_t error) {
// TODO(@jasnell): What should we do with the endpoint?
Debug(this, "Reading data from UDP socket failed. Error %" PRId64, error);
listener_->OnError(error);
}
ReqWrap<uv_udp_send_t>* QuicSocket::OnCreateSendWrap(size_t msg_size) {
HandleScope handle_scope(env()->isolate());
Local<Object> obj;
if (!env()->quicsocketsendwrap_instance_template()
->NewInstance(env()->context()).ToLocal(&obj)) return nullptr;
return last_created_send_wrap_ = new SendWrap(quic_state(), obj, msg_size);
}
void QuicSocket::OnEndpointDone(QuicEndpoint* endpoint) {
Debug(this, "Endpoint has no pending callbacks");
listener_->OnEndpointDone(endpoint);
}
void QuicSocket::OnBind(QuicEndpoint* endpoint) {
SocketAddress local_address = endpoint->local_address();
bound_endpoints_[local_address] =
BaseObjectWeakPtr<QuicEndpoint>(endpoint);
Debug(this, "Endpoint %s bound", local_address);
RecordTimestamp(&QuicSocketStats::bound_at);
}
BaseObjectPtr<QuicSession> QuicSocket::FindSession(const QuicCID& cid) {
BaseObjectPtr<QuicSession> session;
auto session_it = sessions_.find(cid);
if (session_it == std::end(sessions_)) {
auto scid_it = dcid_to_scid_.find(cid);
if (scid_it != std::end(dcid_to_scid_)) {
session_it = sessions_.find(scid_it->second);
CHECK_NE(session_it, std::end(sessions_));
session = session_it->second;
}
} else {
session = session_it->second;
}
return session;
}
// When a received packet contains a QUIC short header but cannot be
// matched to a known QuicSession, it is either (a) garbage,
// (b) a valid packet for a connection we no longer have state
// for, or (c) a stateless reset. Because we do not yet know if
// we are going to process the packet, we need to try to quickly
// determine -- with as little cost as possible -- whether the
// packet contains a reset token. We do so by checking the final
// NGTCP2_STATELESS_RESET_TOKENLEN bytes in the packet to see if
// they match one of the known reset tokens previously given by
// the remote peer. If there's a match, then it's a reset token,
// if not, we move on the to the next check. It is very important
// that this check be as inexpensive as possible to avoid a DOS
// vector.
bool QuicSocket::MaybeStatelessReset(
const QuicCID& dcid,
const QuicCID& scid,
ssize_t nread,
const uint8_t* data,
const SocketAddress& local_addr,
const SocketAddress& remote_addr,
unsigned int flags) {
if (UNLIKELY(state_->stateless_reset_disabled || nread < 16))
return false;
StatelessResetToken possible_token(
data + nread - NGTCP2_STATELESS_RESET_TOKENLEN);
Debug(this, "Possible stateless reset token: %s", possible_token);
auto it = token_map_.find(possible_token);
if (it == token_map_.end())
return false;
Debug(this, "Received a stateless reset token %s", possible_token);
return it->second->Receive(nread, data, local_addr, remote_addr, flags);
}
// When a packet is received here, we do not yet know if we can
// process it successfully as a QUIC packet or not. Given the
// nature of UDP, we may receive a great deal of garbage here
// so it is extremely important not to commit resources until
// we're certain we can process the data we received as QUIC
// packet.
// Any packet we choose not to process must be ignored.
void QuicSocket::OnReceive(
ssize_t nread,
AllocatedBuffer buf,
const SocketAddress& local_addr,
const SocketAddress& remote_addr,
unsigned int flags) {
Debug(this, "Receiving %d bytes from the UDP socket", nread);
// When diagnostic packet loss is enabled, the packet will be randomly
// dropped based on the rx_loss_ probability.
if (UNLIKELY(is_diagnostic_packet_loss(rx_loss_))) {
Debug(this, "Simulating received packet loss");
return;
}
if (UNLIKELY(block_list_->Apply(remote_addr))) {
Debug(this, "Ignoring blocked remote address: %s", remote_addr);
IncrementStat(&QuicSocketStats::packets_ignored);
return;
}
IncrementStat(&QuicSocketStats::bytes_received, nread);
const uint8_t* data = reinterpret_cast<const uint8_t*>(buf.data());
uint32_t pversion;
const uint8_t* pdcid;
size_t pdcidlen;
const uint8_t* pscid;
size_t pscidlen;
// This is our first check to see if the received data can be
// processed as a QUIC packet. If this fails, then the QUIC packet
// header is invalid and cannot be processed; all we can do is ignore
// it. It's questionable whether we should even increment the
// packets_ignored statistic here but for now we do. If it succeeds,
// we have a valid QUIC header but there's still no guarantee that
// the packet can be successfully processed.
if (ngtcp2_pkt_decode_version_cid(
&pversion,
&pdcid,
&pdcidlen,
&pscid,
&pscidlen,
data, nread, kScidLen) < 0) {
IncrementStat(&QuicSocketStats::packets_ignored);
return;
}
// QUIC currently requires CID lengths of max NGTCP2_MAX_CIDLEN. The
// ngtcp2 API allows non-standard lengths, and we may want to allow
// non-standard lengths later. But for now, we're going to ignore any
// packet with a non-standard CID length.
if (pdcidlen > NGTCP2_MAX_CIDLEN || pscidlen > NGTCP2_MAX_CIDLEN) {
IncrementStat(&QuicSocketStats::packets_ignored);
return;
}
QuicCID dcid(pdcid, pdcidlen);
QuicCID scid(pscid, pscidlen);
Debug(this, "Received a QUIC packet for dcid %s", dcid);
BaseObjectPtr<QuicSession> session = FindSession(dcid);
// If a session is not found, there are four possible reasons:
// 1. The session has not been created yet
// 2. The session existed once but we've lost the local state for it
// 3. The packet is a stateless reset sent by the peer
// 4. This is a malicious or malformed packet.
if (!session) {
Debug(this, "There is no existing session for dcid %s", dcid);
bool is_short_header = IsShortHeader(pversion, pscid, pscidlen);
// Handle possible reception of a stateless reset token...
// If it is a stateless reset, the packet will be handled with
// no additional action necessary here. We want to return immediately
// without committing any further resources.
if (is_short_header &&
MaybeStatelessReset(
dcid,
scid,
nread,
data,
local_addr,
remote_addr,
flags)) {
Debug(this, "Handled stateless reset");
return;
}
// AcceptInitialPacket will first validate that the packet can be
// accepted, then create a new server QuicSession instance if able
// to do so. If a new instance cannot be created (for any reason),
// the session BaseObjectPtr will be empty on return.
session = AcceptInitialPacket(
pversion,
dcid,
scid,
nread,
data,
local_addr,
remote_addr,
flags);
// There are many reasons why a server QuicSession could not be
// created. The most common will be invalid packets or incorrect
// QUIC version. In any of these cases, however, to prevent a
// potential attacker from causing us to consume resources,
// we're just going to ignore the packet. It is possible that
// the AcceptInitialPacket sent a version negotiation packet,
// or a CONNECTION_CLOSE packet.
if (!session) {
Debug(this, "Unable to create a new server QuicSession");
// If the packet contained a short header, we might need to send
// a stateless reset. The stateless reset contains a token derived
// from the received destination connection ID.
//
// TODO(@jasnell): Stateless resets are generated programmatically
// using HKDF with the sender provided dcid and a locally provided
// secret as input. It is entirely possible that a malicious
// peer could send multiple stateless reset eliciting packets
// with the specific intent of using the returned stateless
// reset to guess the stateless reset token secret used by
// the server. Once guessed, the malicious peer could use
// that secret as a DOS vector against other peers. We currently
// implement some mitigations for this by limiting the number
// of stateless resets that can be sent to a specific remote
// address but there are other possible mitigations, such as
// including the remote address as input in the generation of
// the stateless token.
if (is_short_header &&
SendStatelessReset(dcid, local_addr, remote_addr, nread)) {
Debug(this, "Sent stateless reset");
IncrementStat(&QuicSocketStats::stateless_reset_count);
return;
}
IncrementStat(&QuicSocketStats::packets_ignored);
return;
}
}
CHECK(session);
// If the QuicSession is already destroyed, there's nothing to do.
if (session->is_destroyed())
return IncrementStat(&QuicSocketStats::packets_ignored);
// If the packet could not successfully processed for any reason (possibly
// due to being malformed or malicious in some way) we mark it ignored.
if (!session->Receive(nread, data, local_addr, remote_addr, flags)) {
IncrementStat(&QuicSocketStats::packets_ignored);
return;
}
IncrementStat(&QuicSocketStats::packets_received);
}
// Generates and sends a version negotiation packet. This is
// terminal for the connection and is sent only when a QUIC
// packet is received for an unsupported Node.js version.
// It is possible that a malicious packet triggered this
// so we need to be careful not to commit too many resources.
// Currently, we only support one QUIC version at a time.
void QuicSocket::SendVersionNegotiation(
uint32_t version,
const QuicCID& dcid,
const QuicCID& scid,
const SocketAddress& local_addr,
const SocketAddress& remote_addr) {
uint32_t sv[2];
sv[0] = GenerateReservedVersion(remote_addr, version);
sv[1] = NGTCP2_PROTO_VER;
uint8_t unused_random;
EntropySource(&unused_random, 1);
size_t pktlen = dcid.length() + scid.length() + (sizeof(sv)) + 7;
auto packet = QuicPacket::Create("version negotiation", pktlen);
ssize_t nwrite = ngtcp2_pkt_write_version_negotiation(
packet->data(),
NGTCP2_MAX_PKTLEN_IPV6,
unused_random,
dcid.data(),
dcid.length(),
scid.data(),
scid.length(),
sv,
arraysize(sv));
if (nwrite <= 0)
return;
packet->set_length(nwrite);
SocketAddress remote_address(remote_addr);
SendPacket(local_addr, remote_address, std::move(packet));
}
// Possible generates and sends a stateless reset packet.
// This is terminal for the connection. It is possible
// that a malicious packet triggered this so we need to
// be careful not to commit too many resources.
bool QuicSocket::SendStatelessReset(
const QuicCID& cid,
const SocketAddress& local_addr,
const SocketAddress& remote_addr,
size_t source_len) {
if (UNLIKELY(state_->stateless_reset_disabled))
return false;
constexpr static size_t kRandlen = NGTCP2_MIN_STATELESS_RESET_RANDLEN * 5;
constexpr static size_t kMinStatelessResetLen = 41;
uint8_t random[kRandlen];
// Per the QUIC spec, we need to protect against sending too
// many stateless reset tokens to an endpoint to prevent
// endless looping.
if (GetCurrentStatelessResetCounter(remote_addr) >=
max_stateless_resets_per_host_) {
return false;
}
// Per the QUIC spec, a stateless reset token must be strictly
// smaller than the packet that triggered it. This is one of the
// mechanisms to prevent infinite looping exchange of stateless
// tokens with the peer.
// An endpoint should never send a stateless reset token smaller than
// 41 bytes per the QUIC spec. The reason is that packets less than
// 41 bytes may allow an observer to determine that it's a stateless
// reset.
size_t pktlen = source_len - 1;
if (pktlen < kMinStatelessResetLen)
return false;
StatelessResetToken token(reset_token_secret_, cid);
EntropySource(random, kRandlen);
auto packet = QuicPacket::Create("stateless reset", pktlen);
ssize_t nwrite =
ngtcp2_pkt_write_stateless_reset(
packet->data(),
NGTCP2_MAX_PKTLEN_IPV4,
const_cast<uint8_t*>(token.data()),
random,
kRandlen);
if (nwrite < static_cast<ssize_t>(kMinStatelessResetLen))
return false;
packet->set_length(nwrite);
SocketAddress remote_address(remote_addr);
IncrementStatelessResetCounter(remote_address);
return SendPacket(local_addr, remote_address, std::move(packet)) == 0;
}
// Generates and sends a retry packet. This is terminal
// for the connection. Retry packets are used to force
// explicit path validation by issuing a token to the
// peer that it must thereafter include in all subsequent
// initial packets. Upon receiving a retry packet, the
// peer must termination it's initial attempt to
// establish a connection and start a new attempt.
//
// Retry packets will only ever be generated by QUIC servers,
// and only if the QuicSocket is configured for explicit path
// validation. There is no way for a client to force a retry
// packet to be created. However, once a client determines that
// explicit path validation is enabled, it could attempt to
// DOS by sending a large number of malicious initial packets
// to intentionally ellicit retry packets (It can do so by
// intentionally sending initial packets that ignore the retry
// token). To help mitigate that risk, we limit the number of
// retries we send to a given remote endpoint.
bool QuicSocket::SendRetry(
const QuicCID& dcid,
const QuicCID& scid,
const SocketAddress& local_addr,
const SocketAddress& remote_addr) {
auto info = addrLRU_.Upsert(remote_addr);
// Do not send a retry if the retry count is greater
// than the retry limit.
// TODO(@jasnell): Make the retry limit configurable.
if (++(info->retry_count) > DEFAULT_MAX_RETRY_LIMIT)
return true;
std::unique_ptr<QuicPacket> packet =
GenerateRetryPacket(token_secret_, dcid, scid, local_addr, remote_addr);
return packet ?
SendPacket(local_addr, remote_addr, std::move(packet)) == 0 : false;
}
// Shutdown a connection prematurely, before a QuicSession is created.
// This should only be called t the start of a session before the crypto
// keys have been established.
void QuicSocket::ImmediateConnectionClose(
const QuicCID& scid,
const QuicCID& dcid,
const SocketAddress& local_addr,
const SocketAddress& remote_addr,
int64_t reason) {
Debug(this, "Sending stateless connection close to %s", scid);
auto packet = QuicPacket::Create("immediate connection close");
ssize_t nwrite = ngtcp2_crypto_write_connection_close(
packet->data(),
packet->length(),
scid.cid(),
dcid.cid(),
reason);
if (nwrite > 0) {
packet->set_length(nwrite);
SendPacket(local_addr, remote_addr, std::move(packet));
}
}
// Inspects the packet and possibly accepts it as a new
// initial packet creating a new QuicSession instance.
// If the packet is not acceptable, it is very important
// not to commit resources.
BaseObjectPtr<QuicSession> QuicSocket::AcceptInitialPacket(
uint32_t version,
const QuicCID& dcid,
const QuicCID& scid,
ssize_t nread,
const uint8_t* data,
const SocketAddress& local_addr,
const SocketAddress& remote_addr,
unsigned int flags) {
HandleScope handle_scope(env()->isolate());
Context::Scope context_scope(env()->context());
ngtcp2_pkt_hd hd;
QuicCID ocid;
// If the QuicSocket is not listening, the paket will be ignored.
if (!state_->server_listening) {
Debug(this, "QuicSocket is not listening");
return {};
}
switch (ngtcp2_accept(&hd, data, static_cast<size_t>(nread))) {
case 1:
// Send Version Negotiation
SendVersionNegotiation(version, dcid, scid, local_addr, remote_addr);
// Fall through
case -1:
// Either a version negotiation packet was sent or the packet is
// an invalid initial packet. Either way, there's nothing more we
// can do here.
return {};
}
// If the server is busy, new connections will be shut down immediately
// after the initial keys are installed. The busy state is controlled
// entirely by local user code. It is important to understand that
// a QuicSession is created and resources are committed even though
// the QuicSession will be torn down as quickly as possible.
// Else, check to see if the number of connections total for this QuicSocket
// has been exceeded. If the count has been exceeded, shutdown the connection
// immediately after the initial keys are installed.
if (UNLIKELY(state_->server_busy == 1) ||
sessions_.size() >= max_connections_ ||
GetCurrentSocketAddressCounter(remote_addr) >=
max_connections_per_host_) {
Debug(this, "QuicSocket is busy or connection count exceeded");
IncrementStat(&QuicSocketStats::server_busy_count);
ImmediateConnectionClose(
QuicCID(hd.scid),
QuicCID(hd.dcid),
local_addr,
remote_addr,
NGTCP2_CONNECTION_REFUSED);
return {};
}
// QUIC has address validation built in to the handshake but allows for
// an additional explicit validation request using RETRY frames. If we
// are using explicit validation, we check for the existence of a valid
// retry token in the packet. If one does not exist, we send a retry with
// a new token. If it does exist, and if it's valid, we grab the original
// cid and continue.
if (!is_validated_address(remote_addr)) {
switch (hd.type) {
case NGTCP2_PKT_INITIAL:
if (has_option_validate_address() || hd.token.len > 0) {
Debug(this, "Performing explicit address validation");
if (hd.token.len == 0) {
Debug(this, "No retry token was detected. Generating one");
SendRetry(dcid, scid, local_addr, remote_addr);
// Sending a retry token terminates this connection attempt.
return {};
}
if (InvalidRetryToken(
hd.token,
remote_addr,
&ocid,
token_secret_,
retry_token_expiration_)) {
Debug(this, "Invalid retry token was detected. Failing");
ImmediateConnectionClose(
QuicCID(hd.scid),
QuicCID(hd.dcid),
local_addr,
remote_addr);
return {};
}
}
break;
case NGTCP2_PKT_0RTT:
SendRetry(dcid, scid, local_addr, remote_addr);
return {};
}
}
BaseObjectPtr<QuicSession> session =
QuicSession::CreateServer(
this,
server_session_config_,
local_addr,
remote_addr,
scid,
dcid,
ocid,
version,
server_alpn_,
server_options_,
qlog_);
CHECK(session);
listener_->OnSessionReady(session);
// It's possible that the session was destroyed while processing
// the ready callback. If it was, then we need to send an early
// CONNECTION_CLOSE.
if (session->is_destroyed()) {
ImmediateConnectionClose(
QuicCID(hd.scid),
QuicCID(hd.dcid),
local_addr,
remote_addr,
NGTCP2_CONNECTION_REFUSED);
} else {
session->set_wrapped();
}
return session;
}
QuicSocket::SendWrap::SendWrap(
QuicState* quic_state,
Local<Object> req_wrap_obj,
size_t total_length)
: ReqWrap(quic_state->env(), req_wrap_obj, PROVIDER_QUICSOCKET),
total_length_(total_length),
quic_state_(quic_state) {
}
std::string QuicSocket::SendWrap::MemoryInfoName() const {
return "QuicSendWrap";
}
void QuicSocket::SendWrap::MemoryInfo(MemoryTracker* tracker) const {
tracker->TrackField("session", session_);
tracker->TrackField("packet", packet_);
}
int QuicSocket::SendPacket(
const SocketAddress& local_addr,
const SocketAddress& remote_addr,
std::unique_ptr<QuicPacket> packet,
BaseObjectPtr<QuicSession> session) {
// If the packet is empty, there's nothing to do
if (packet->length() == 0)
return 0;
Debug(this, "Sending %" PRIu64 " bytes to %s from %s (label: %s)",
packet->length(),
remote_addr,
local_addr,
packet->diagnostic_label());
// If DiagnosticPacketLoss returns true, it will call Done() internally
if (UNLIKELY(is_diagnostic_packet_loss(tx_loss_))) {
Debug(this, "Simulating transmitted packet loss");
return 0;
}
last_created_send_wrap_ = nullptr;
uv_buf_t buf = packet->buf();
auto endpoint = bound_endpoints_.find(local_addr);
CHECK_NE(endpoint, bound_endpoints_.end());
int err = endpoint->second->Send(&buf, 1, remote_addr.data());
if (err != 0) {
if (err > 0) err = 0;
OnSend(err, packet.get());
} else {
CHECK_NOT_NULL(last_created_send_wrap_);
last_created_send_wrap_->set_packet(std::move(packet));
if (session)
last_created_send_wrap_->set_session(session);
}
return err;
}
void QuicSocket::OnSend(int status, QuicPacket* packet) {
if (status == 0) {
Debug(this, "Sent %" PRIu64 " bytes (label: %s)",
packet->length(),
packet->diagnostic_label());
IncrementStat(&QuicSocketStats::bytes_sent, packet->length());
IncrementStat(&QuicSocketStats::packets_sent);
} else {
Debug(this, "Failed to send %" PRIu64 " bytes (status: %d, label: %s)",
packet->length(),
status,
packet->diagnostic_label());
}
}
void QuicSocket::OnSendDone(ReqWrap<uv_udp_send_t>* wrap, int status) {
std::unique_ptr<SendWrap> req_wrap(static_cast<SendWrap*>(wrap));
OnSend(status, req_wrap->packet());
}
void QuicSocket::CheckAllocatedSize(size_t previous_size) const {
CHECK_GE(current_ngtcp2_memory_, previous_size);
}
void QuicSocket::IncreaseAllocatedSize(size_t size) {
current_ngtcp2_memory_ += size;
}
void QuicSocket::DecreaseAllocatedSize(size_t size) {
current_ngtcp2_memory_ -= size;
}
void QuicSocket::PushListener(QuicSocketListener* listener) {
CHECK_NOT_NULL(listener);
CHECK(!listener->socket_);
listener->previous_listener_ = listener_;
listener->socket_.reset(this);
listener_ = listener;
}
void QuicSocket::RemoveListener(QuicSocketListener* listener) {
CHECK_NOT_NULL(listener);
QuicSocketListener* previous;
QuicSocketListener* current;
for (current = listener_, previous = nullptr;
/* No loop condition because we want a crash if listener is not found */
; previous = current, current = current->previous_listener_) {
CHECK_NOT_NULL(current);
if (current == listener) {
if (previous != nullptr)
previous->previous_listener_ = current->previous_listener_;
else
listener_ = listener->previous_listener_;
break;
}
}
listener->socket_.reset();
listener->previous_listener_ = nullptr;
}
bool QuicSocket::SocketAddressInfoTraits::CheckExpired(
const SocketAddress& address,
const Type& type) {
return (uv_hrtime() - type.timestamp) > 1e10; // 10 seconds.
}
void QuicSocket::SocketAddressInfoTraits::Touch(
const SocketAddress& address,
Type* type) {
type->timestamp = uv_hrtime();
}
// JavaScript API
namespace {
void NewQuicEndpoint(const FunctionCallbackInfo<Value>& args) {
QuicState* state = Environment::GetBindingData<QuicState>(args);
CHECK(args.IsConstructCall());
CHECK(args[0]->IsObject());
QuicSocket* socket;
ASSIGN_OR_RETURN_UNWRAP(&socket, args[0].As<Object>());
CHECK(args[1]->IsObject());
CHECK_GE(args[1].As<Object>()->InternalFieldCount(),
UDPWrapBase::kUDPWrapBaseField);
new QuicEndpoint(state, args.This(), socket, args[1].As<Object>());
}
void NewQuicSocket(const FunctionCallbackInfo<Value>& args) {
QuicState* state = Environment::GetBindingData<QuicState>(args);
Environment* env = state->env();
CHECK(args.IsConstructCall());
uint32_t options;
uint32_t retry_token_expiration;
uint32_t max_connections;
uint32_t max_connections_per_host;
uint32_t max_stateless_resets_per_host;
if (!args[0]->Uint32Value(env->context()).To(&options) ||
!args[1]->Uint32Value(env->context()).To(&retry_token_expiration) ||
!args[2]->Uint32Value(env->context()).To(&max_connections) ||
!args[3]->Uint32Value(env->context()).To(&max_connections_per_host) ||
!args[4]->Uint32Value(env->context())
.To(&max_stateless_resets_per_host)) {
return;
}
CHECK_GE(retry_token_expiration, MIN_RETRYTOKEN_EXPIRATION);
CHECK_LE(retry_token_expiration, MAX_RETRYTOKEN_EXPIRATION);
const uint8_t* session_reset_secret = nullptr;
if (args[6]->IsArrayBufferView()) {
ArrayBufferViewContents<uint8_t> buf(args[6].As<ArrayBufferView>());
CHECK_EQ(buf.length(), kTokenSecretLen);
session_reset_secret = buf.data();
}
new QuicSocket(
state,
args.This(),
retry_token_expiration,
max_connections,
max_connections_per_host,
max_stateless_resets_per_host,
options,
args[5]->IsTrue() ? QlogMode::kEnabled : QlogMode::kDisabled,
session_reset_secret,
args[7]->IsTrue());
}
void QuicSocketAddEndpoint(const FunctionCallbackInfo<Value>& args) {
QuicSocket* socket;
ASSIGN_OR_RETURN_UNWRAP(&socket, args.Holder());
CHECK(args[0]->IsObject());
QuicEndpoint* endpoint;
ASSIGN_OR_RETURN_UNWRAP(&endpoint, args[0].As<Object>());
socket->AddEndpoint(
BaseObjectPtr<QuicEndpoint>(endpoint),
args[1]->IsTrue());
}
// Enabling diagnostic packet loss enables a mode where the QuicSocket
// instance will randomly ignore received packets in order to simulate
// packet loss. This is not an API that should be enabled in production
// but is useful when debugging and diagnosing performance issues.
// Diagnostic packet loss is enabled by setting either the tx or rx
// arguments to a value between 0.0 and 1.0. Setting both values to 0.0
// disables the mechanism.
void QuicSocketSetDiagnosticPacketLoss(
const FunctionCallbackInfo<Value>& args) {
Environment* env = Environment::GetCurrent(args);
QuicSocket* socket;
ASSIGN_OR_RETURN_UNWRAP(&socket, args.Holder());
double rx, tx;
if (!args[0]->NumberValue(env->context()).To(&rx) ||
!args[1]->NumberValue(env->context()).To(&tx)) return;
CHECK_GE(rx, 0.0f);
CHECK_GE(tx, 0.0f);
CHECK_LE(rx, 1.0f);
CHECK_LE(tx, 1.0f);
socket->set_diagnostic_packet_loss(rx, tx);
}
void QuicSocketDestroy(const FunctionCallbackInfo<Value>& args) {
QuicSocket* socket;
ASSIGN_OR_RETURN_UNWRAP(&socket, args.Holder());
socket->ReceiveStop();
}
void QuicSocketListen(const FunctionCallbackInfo<Value>& args) {
Environment* env = Environment::GetCurrent(args);
QuicSocket* socket;
ASSIGN_OR_RETURN_UNWRAP(&socket, args.Holder(),
args.GetReturnValue().Set(UV_EBADF));
CHECK(args[0]->IsObject() &&
env->secure_context_constructor_template()->HasInstance(args[0]));
SecureContext* sc;
ASSIGN_OR_RETURN_UNWRAP(&sc, args[0].As<Object>(),
args.GetReturnValue().Set(UV_EBADF));
sockaddr_storage preferred_address_storage;
const sockaddr* preferred_address = nullptr;
if (args[1]->IsString()) {
node::Utf8Value preferred_address_host(args.GetIsolate(), args[1]);
int32_t preferred_address_family;
uint32_t preferred_address_port;
if (!args[2]->Int32Value(env->context()).To(&preferred_address_family) ||
!args[3]->Uint32Value(env->context()).To(&preferred_address_port))
return;
if (SocketAddress::ToSockAddr(
preferred_address_family,
*preferred_address_host,
preferred_address_port,
&preferred_address_storage)) {
preferred_address =
reinterpret_cast<const sockaddr*>(&preferred_address_storage);
}
}
std::string alpn(NGHTTP3_ALPN_H3);
if (args[4]->IsString()) {
Utf8Value val(env->isolate(), args[4]);
alpn = val.length();
alpn += *val;
}
uint32_t options = 0;
if (!args[5]->Uint32Value(env->context()).To(&options)) return;
socket->Listen(
BaseObjectPtr<SecureContext>(sc),
preferred_address,
alpn,
options);
}
void QuicEndpointWaitForPendingCallbacks(
const FunctionCallbackInfo<Value>& args) {
QuicEndpoint* endpoint;
ASSIGN_OR_RETURN_UNWRAP(&endpoint, args.Holder());
endpoint->WaitForPendingCallbacks();
}
} // namespace
void QuicEndpoint::Initialize(
Environment* env,
Local<Object> target,
Local<Context> context) {
Isolate* isolate = env->isolate();
Local<String> class_name = FIXED_ONE_BYTE_STRING(isolate, "QuicEndpoint");
Local<FunctionTemplate> endpoint = env->NewFunctionTemplate(NewQuicEndpoint);
endpoint->Inherit(BaseObject::GetConstructorTemplate(env));
endpoint->SetClassName(class_name);
endpoint->InstanceTemplate()->SetInternalFieldCount(
QuicEndpoint::kInternalFieldCount);
env->SetProtoMethod(endpoint,
"waitForPendingCallbacks",
QuicEndpointWaitForPendingCallbacks);
endpoint->InstanceTemplate()->Set(env->owner_symbol(), Null(isolate));
target->Set(
context,
class_name,
endpoint->GetFunction(context).ToLocalChecked())
.FromJust();
}
void QuicSocket::Initialize(
Environment* env,
Local<Object> target,
Local<Context> context) {
Isolate* isolate = env->isolate();
Local<String> class_name = FIXED_ONE_BYTE_STRING(isolate, "QuicSocket");
Local<FunctionTemplate> socket = env->NewFunctionTemplate(NewQuicSocket);
socket->Inherit(AsyncWrap::GetConstructorTemplate(env));
socket->SetClassName(class_name);
socket->InstanceTemplate()->SetInternalFieldCount(
QuicSocket::kInternalFieldCount);
socket->InstanceTemplate()->Set(env->owner_symbol(), Null(isolate));
env->SetProtoMethod(socket,
"addEndpoint",
QuicSocketAddEndpoint);
env->SetProtoMethod(socket,
"destroy",
QuicSocketDestroy);
env->SetProtoMethod(socket,
"listen",
QuicSocketListen);
env->SetProtoMethod(socket,
"setDiagnosticPacketLoss",
QuicSocketSetDiagnosticPacketLoss);
socket->Inherit(HandleWrap::GetConstructorTemplate(env));
target->Set(context, class_name,
socket->GetFunction(env->context()).ToLocalChecked()).FromJust();
Local<FunctionTemplate> sendwrap_ctor = FunctionTemplate::New(isolate);
sendwrap_ctor->Inherit(AsyncWrap::GetConstructorTemplate(env));
sendwrap_ctor->SetClassName(FIXED_ONE_BYTE_STRING(isolate, "SendWrap"));
Local<ObjectTemplate> sendwrap_template = sendwrap_ctor->InstanceTemplate();
sendwrap_template->SetInternalFieldCount(SendWrap::kInternalFieldCount);
env->set_quicsocketsendwrap_instance_template(sendwrap_template);
}
} // namespace quic
} // namespace node
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