blob: 167141f8f92003eddea8f989aef9f8ff7b77370b [file] [log] [blame]
// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "net/quic/quic_session.h"
#include "base/stl_util.h"
#include "net/quic/crypto/proof_verifier.h"
#include "net/quic/quic_connection.h"
#include "net/quic/quic_flags.h"
#include "net/quic/quic_flow_controller.h"
#include "net/ssl/ssl_info.h"
using base::StringPiece;
using base::hash_map;
using base::hash_set;
using std::make_pair;
using std::map;
using std::max;
using std::string;
using std::vector;
namespace net {
#define ENDPOINT \
(perspective() == Perspective::IS_SERVER ? "Server: " : " Client: ")
// We want to make sure we delete any closed streams in a safe manner.
// To avoid deleting a stream in mid-operation, we have a simple shim between
// us and the stream, so we can delete any streams when we return from
// processing.
//
// We could just override the base methods, but this makes it easier to make
// sure we don't miss any.
class VisitorShim : public QuicConnectionVisitorInterface {
public:
explicit VisitorShim(QuicSession* session) : session_(session) {}
void OnStreamFrame(const QuicStreamFrame& frame) override {
session_->OnStreamFrame(frame);
session_->PostProcessAfterData();
}
void OnRstStream(const QuicRstStreamFrame& frame) override {
session_->OnRstStream(frame);
session_->PostProcessAfterData();
}
void OnGoAway(const QuicGoAwayFrame& frame) override {
session_->OnGoAway(frame);
session_->PostProcessAfterData();
}
void OnWindowUpdateFrame(const QuicWindowUpdateFrame& frame) override {
session_->OnWindowUpdateFrame(frame);
session_->PostProcessAfterData();
}
void OnBlockedFrame(const QuicBlockedFrame& frame) override {
session_->OnBlockedFrame(frame);
session_->PostProcessAfterData();
}
void OnCanWrite() override {
session_->OnCanWrite();
session_->PostProcessAfterData();
}
void OnCongestionWindowChange(QuicTime now) override {
session_->OnCongestionWindowChange(now);
}
void OnSuccessfulVersionNegotiation(const QuicVersion& version) override {
session_->OnSuccessfulVersionNegotiation(version);
}
void OnConnectionClosed(QuicErrorCode error, bool from_peer) override {
session_->OnConnectionClosed(error, from_peer);
// The session will go away, so don't bother with cleanup.
}
void OnWriteBlocked() override { session_->OnWriteBlocked(); }
bool WillingAndAbleToWrite() const override {
return session_->WillingAndAbleToWrite();
}
bool HasPendingHandshake() const override {
return session_->HasPendingHandshake();
}
bool HasOpenDynamicStreams() const override {
return session_->HasOpenDynamicStreams();
}
private:
QuicSession* session_;
};
QuicSession::QuicSession(QuicConnection* connection, const QuicConfig& config)
: connection_(connection),
visitor_shim_(new VisitorShim(this)),
config_(config),
max_open_streams_(config_.MaxStreamsPerConnection()),
next_stream_id_(perspective() == Perspective::IS_SERVER ? 2 : 3),
largest_peer_created_stream_id_(
perspective() == Perspective::IS_SERVER ? 1 : 0),
error_(QUIC_NO_ERROR),
flow_controller_(connection_.get(),
0,
perspective(),
kMinimumFlowControlSendWindow,
config_.GetInitialSessionFlowControlWindowToSend(),
false),
goaway_received_(false),
goaway_sent_(false),
has_pending_handshake_(false) {
}
void QuicSession::Initialize() {
connection_->set_visitor(visitor_shim_.get());
connection_->SetFromConfig(config_);
DCHECK_EQ(kCryptoStreamId, GetCryptoStream()->id());
static_stream_map_[kCryptoStreamId] = GetCryptoStream();
}
QuicSession::~QuicSession() {
STLDeleteElements(&closed_streams_);
STLDeleteValues(&dynamic_stream_map_);
DLOG_IF(WARNING,
locally_closed_streams_highest_offset_.size() > max_open_streams_)
<< "Surprisingly high number of locally closed streams still waiting for "
"final byte offset: " << locally_closed_streams_highest_offset_.size();
}
void QuicSession::OnStreamFrame(const QuicStreamFrame& frame) {
// TODO(rch) deal with the error case of stream id 0.
QuicStreamId stream_id = frame.stream_id;
ReliableQuicStream* stream = GetStream(stream_id);
if (!stream) {
// The stream no longer exists, but we may still be interested in the
// final stream byte offset sent by the peer. A frame with a FIN can give
// us this offset.
if (frame.fin) {
QuicStreamOffset final_byte_offset = frame.offset + frame.data.size();
UpdateFlowControlOnFinalReceivedByteOffset(stream_id, final_byte_offset);
}
return;
}
stream->OnStreamFrame(frame);
}
void QuicSession::OnRstStream(const QuicRstStreamFrame& frame) {
if (ContainsKey(static_stream_map_, frame.stream_id)) {
connection()->SendConnectionCloseWithDetails(
QUIC_INVALID_STREAM_ID, "Attempt to reset a static stream");
return;
}
ReliableQuicStream* stream = GetDynamicStream(frame.stream_id);
if (!stream) {
// The RST frame contains the final byte offset for the stream: we can now
// update the connection level flow controller if needed.
UpdateFlowControlOnFinalReceivedByteOffset(frame.stream_id,
frame.byte_offset);
return; // Errors are handled by GetStream.
}
stream->OnStreamReset(frame);
}
void QuicSession::OnGoAway(const QuicGoAwayFrame& frame) {
DCHECK(frame.last_good_stream_id < next_stream_id_);
goaway_received_ = true;
}
void QuicSession::OnConnectionClosed(QuicErrorCode error, bool from_peer) {
DCHECK(!connection_->connected());
if (error_ == QUIC_NO_ERROR) {
error_ = error;
}
while (!dynamic_stream_map_.empty()) {
StreamMap::iterator it = dynamic_stream_map_.begin();
QuicStreamId id = it->first;
it->second->OnConnectionClosed(error, from_peer);
// The stream should call CloseStream as part of OnConnectionClosed.
if (dynamic_stream_map_.find(id) != dynamic_stream_map_.end()) {
LOG(DFATAL) << ENDPOINT
<< "Stream failed to close under OnConnectionClosed";
CloseStream(id);
}
}
}
void QuicSession::OnSuccessfulVersionNegotiation(const QuicVersion& version) {
}
void QuicSession::OnWindowUpdateFrame(const QuicWindowUpdateFrame& frame) {
// Stream may be closed by the time we receive a WINDOW_UPDATE, so we can't
// assume that it still exists.
QuicStreamId stream_id = frame.stream_id;
if (stream_id == kConnectionLevelId) {
// This is a window update that applies to the connection, rather than an
// individual stream.
DVLOG(1) << ENDPOINT << "Received connection level flow control window "
"update with byte offset: "
<< frame.byte_offset;
if (flow_controller_.UpdateSendWindowOffset(frame.byte_offset)) {
// Connection level flow control window has increased, so blocked streams
// can write again.
// TODO(ianswett): I suspect this can be delayed until the packet
// processing is complete.
if (!FLAGS_quic_dont_write_when_flow_unblocked) {
OnCanWrite();
}
}
return;
}
ReliableQuicStream* stream = GetStream(stream_id);
if (stream) {
stream->OnWindowUpdateFrame(frame);
}
}
void QuicSession::OnBlockedFrame(const QuicBlockedFrame& frame) {
// TODO(rjshade): Compare our flow control receive windows for specified
// streams: if we have a large window then maybe something
// had gone wrong with the flow control accounting.
DVLOG(1) << ENDPOINT
<< "Received BLOCKED frame with stream id: " << frame.stream_id;
}
void QuicSession::OnCanWrite() {
// We limit the number of writes to the number of pending streams. If more
// streams become pending, WillingAndAbleToWrite will be true, which will
// cause the connection to request resumption before yielding to other
// connections.
size_t num_writes = write_blocked_streams_.NumBlockedStreams();
if (flow_controller_.IsBlocked()) {
// If we are connection level flow control blocked, then only allow the
// crypto and headers streams to try writing as all other streams will be
// blocked.
num_writes = 0;
if (write_blocked_streams_.crypto_stream_blocked()) {
num_writes += 1;
}
if (write_blocked_streams_.headers_stream_blocked()) {
num_writes += 1;
}
}
if (num_writes == 0) {
return;
}
QuicConnection::ScopedPacketBundler ack_bundler(
connection_.get(), QuicConnection::NO_ACK);
for (size_t i = 0; i < num_writes; ++i) {
if (!(write_blocked_streams_.HasWriteBlockedCryptoOrHeadersStream() ||
write_blocked_streams_.HasWriteBlockedDataStreams())) {
// Writing one stream removed another!? Something's broken.
LOG(DFATAL) << "WriteBlockedStream is missing";
connection_->CloseConnection(QUIC_INTERNAL_ERROR, false);
return;
}
if (!connection_->CanWriteStreamData()) {
return;
}
QuicStreamId stream_id = write_blocked_streams_.PopFront();
if (stream_id == kCryptoStreamId) {
has_pending_handshake_ = false; // We just popped it.
}
ReliableQuicStream* stream = GetStream(stream_id);
if (stream != nullptr && !stream->flow_controller()->IsBlocked()) {
// If the stream can't write all bytes, it'll re-add itself to the blocked
// list.
stream->OnCanWrite();
}
}
}
bool QuicSession::WillingAndAbleToWrite() const {
// If the crypto or headers streams are blocked, we want to schedule a write -
// they don't get blocked by connection level flow control. Otherwise only
// schedule a write if we are not flow control blocked at the connection
// level.
return write_blocked_streams_.HasWriteBlockedCryptoOrHeadersStream() ||
(!flow_controller_.IsBlocked() &&
write_blocked_streams_.HasWriteBlockedDataStreams());
}
bool QuicSession::HasPendingHandshake() const {
return has_pending_handshake_;
}
bool QuicSession::HasOpenDynamicStreams() const {
return GetNumOpenStreams() > 0;
}
QuicConsumedData QuicSession::WritevData(
QuicStreamId id,
const QuicIOVector& iov,
QuicStreamOffset offset,
bool fin,
FecProtection fec_protection,
QuicAckNotifier::DelegateInterface* ack_notifier_delegate) {
return connection_->SendStreamData(id, iov, offset, fin, fec_protection,
ack_notifier_delegate);
}
void QuicSession::SendRstStream(QuicStreamId id,
QuicRstStreamErrorCode error,
QuicStreamOffset bytes_written) {
if (ContainsKey(static_stream_map_, id)) {
LOG(DFATAL) << "Cannot send RST for a static stream with ID " << id;
return;
}
if (connection()->connected()) {
// Only send a RST_STREAM frame if still connected.
connection_->SendRstStream(id, error, bytes_written);
}
CloseStreamInner(id, true);
}
void QuicSession::SendGoAway(QuicErrorCode error_code, const string& reason) {
if (goaway_sent_) {
return;
}
goaway_sent_ = true;
connection_->SendGoAway(error_code, largest_peer_created_stream_id_, reason);
}
void QuicSession::CloseStream(QuicStreamId stream_id) {
CloseStreamInner(stream_id, false);
}
void QuicSession::CloseStreamInner(QuicStreamId stream_id,
bool locally_reset) {
DVLOG(1) << ENDPOINT << "Closing stream " << stream_id;
StreamMap::iterator it = dynamic_stream_map_.find(stream_id);
if (it == dynamic_stream_map_.end()) {
// When CloseStreamInner has been called recursively (via
// ReliableQuicStream::OnClose), the stream will already have been deleted
// from stream_map_, so return immediately.
DVLOG(1) << ENDPOINT << "Stream is already closed: " << stream_id;
return;
}
ReliableQuicStream* stream = it->second;
// Tell the stream that a RST has been sent.
if (locally_reset) {
stream->set_rst_sent(true);
}
closed_streams_.push_back(it->second);
// If we haven't received a FIN or RST for this stream, we need to keep track
// of the how many bytes the stream's flow controller believes it has
// received, for accurate connection level flow control accounting.
if (!stream->HasFinalReceivedByteOffset()) {
locally_closed_streams_highest_offset_[stream_id] =
stream->flow_controller()->highest_received_byte_offset();
}
dynamic_stream_map_.erase(it);
draining_streams_.erase(stream_id);
stream->OnClose();
// Decrease the number of streams being emulated when a new one is opened.
connection_->SetNumOpenStreams(dynamic_stream_map_.size());
}
void QuicSession::UpdateFlowControlOnFinalReceivedByteOffset(
QuicStreamId stream_id, QuicStreamOffset final_byte_offset) {
map<QuicStreamId, QuicStreamOffset>::iterator it =
locally_closed_streams_highest_offset_.find(stream_id);
if (it == locally_closed_streams_highest_offset_.end()) {
return;
}
DVLOG(1) << ENDPOINT << "Received final byte offset " << final_byte_offset
<< " for stream " << stream_id;
QuicByteCount offset_diff = final_byte_offset - it->second;
if (flow_controller_.UpdateHighestReceivedOffset(
flow_controller_.highest_received_byte_offset() + offset_diff)) {
// If the final offset violates flow control, close the connection now.
if (flow_controller_.FlowControlViolation()) {
connection_->SendConnectionClose(
QUIC_FLOW_CONTROL_RECEIVED_TOO_MUCH_DATA);
return;
}
}
flow_controller_.AddBytesConsumed(offset_diff);
locally_closed_streams_highest_offset_.erase(it);
}
bool QuicSession::IsEncryptionEstablished() {
return GetCryptoStream()->encryption_established();
}
bool QuicSession::IsCryptoHandshakeConfirmed() {
return GetCryptoStream()->handshake_confirmed();
}
void QuicSession::OnConfigNegotiated() {
connection_->SetFromConfig(config_);
uint32 max_streams = config_.MaxStreamsPerConnection();
if (perspective() == Perspective::IS_SERVER) {
// A server should accept a small number of additional streams beyond the
// limit sent to the client. This helps avoid early connection termination
// when FIN/RSTs for old streams are lost or arrive out of order.
// Use a minimum number of additional streams, or a percentage increase,
// whichever is larger.
max_streams =
max(max_streams + kMaxStreamsMinimumIncrement,
static_cast<uint32>(max_streams * kMaxStreamsMultiplier));
if (config_.HasReceivedConnectionOptions()) {
if (ContainsQuicTag(config_.ReceivedConnectionOptions(), kAFCW)) {
EnableAutoTuneReceiveWindow();
}
// The following variations change the initial receive flow control window
// size for streams. For simplicity reasons, do not try to effect
// existing streams but only future ones.
if (ContainsQuicTag(config_.ReceivedConnectionOptions(), kIFW5)) {
config_.SetInitialStreamFlowControlWindowToSend(32 * 1024);
}
if (ContainsQuicTag(config_.ReceivedConnectionOptions(), kIFW6)) {
config_.SetInitialStreamFlowControlWindowToSend(64 * 1024);
}
if (ContainsQuicTag(config_.ReceivedConnectionOptions(), kIFW7)) {
config_.SetInitialStreamFlowControlWindowToSend(128 * 1024);
}
}
}
set_max_open_streams(max_streams);
if (config_.HasReceivedInitialStreamFlowControlWindowBytes()) {
// Streams which were created before the SHLO was received (0-RTT
// requests) are now informed of the peer's initial flow control window.
OnNewStreamFlowControlWindow(
config_.ReceivedInitialStreamFlowControlWindowBytes());
}
if (config_.HasReceivedInitialSessionFlowControlWindowBytes()) {
OnNewSessionFlowControlWindow(
config_.ReceivedInitialSessionFlowControlWindowBytes());
}
}
void QuicSession::EnableAutoTuneReceiveWindow() {
flow_controller_.set_auto_tune_receive_window(true);
// Inform all existing streams about the new window.
for (auto const& kv : static_stream_map_) {
kv.second->flow_controller()->set_auto_tune_receive_window(true);
}
for (auto const& kv : dynamic_stream_map_) {
kv.second->flow_controller()->set_auto_tune_receive_window(true);
}
}
void QuicSession::OnNewStreamFlowControlWindow(QuicStreamOffset new_window) {
if (new_window < kMinimumFlowControlSendWindow) {
LOG(ERROR) << "Peer sent us an invalid stream flow control send window: "
<< new_window
<< ", below default: " << kMinimumFlowControlSendWindow;
if (connection_->connected()) {
connection_->SendConnectionClose(QUIC_FLOW_CONTROL_INVALID_WINDOW);
}
return;
}
// Inform all existing streams about the new window.
for (auto const& kv : static_stream_map_) {
kv.second->UpdateSendWindowOffset(new_window);
}
for (auto const& kv : dynamic_stream_map_) {
kv.second->UpdateSendWindowOffset(new_window);
}
}
void QuicSession::OnNewSessionFlowControlWindow(QuicStreamOffset new_window) {
if (new_window < kMinimumFlowControlSendWindow) {
LOG(ERROR) << "Peer sent us an invalid session flow control send window: "
<< new_window
<< ", below default: " << kMinimumFlowControlSendWindow;
if (connection_->connected()) {
connection_->SendConnectionClose(QUIC_FLOW_CONTROL_INVALID_WINDOW);
}
return;
}
flow_controller_.UpdateSendWindowOffset(new_window);
}
void QuicSession::OnCryptoHandshakeEvent(CryptoHandshakeEvent event) {
switch (event) {
// TODO(satyamshekhar): Move the logic of setting the encrypter/decrypter
// to QuicSession since it is the glue.
case ENCRYPTION_FIRST_ESTABLISHED:
break;
case ENCRYPTION_REESTABLISHED:
// Retransmit originally packets that were sent, since they can't be
// decrypted by the peer.
connection_->RetransmitUnackedPackets(ALL_INITIAL_RETRANSMISSION);
break;
case HANDSHAKE_CONFIRMED:
LOG_IF(DFATAL, !config_.negotiated()) << ENDPOINT
<< "Handshake confirmed without parameter negotiation.";
// Discard originally encrypted packets, since they can't be decrypted by
// the peer.
connection_->NeuterUnencryptedPackets();
break;
default:
LOG(ERROR) << ENDPOINT << "Got unknown handshake event: " << event;
}
}
void QuicSession::OnCryptoHandshakeMessageSent(
const CryptoHandshakeMessage& message) {
}
void QuicSession::OnCryptoHandshakeMessageReceived(
const CryptoHandshakeMessage& message) {
}
QuicConfig* QuicSession::config() {
return &config_;
}
void QuicSession::ActivateStream(ReliableQuicStream* stream) {
DVLOG(1) << ENDPOINT << "num_streams: " << dynamic_stream_map_.size()
<< ". activating " << stream->id();
DCHECK(!ContainsKey(dynamic_stream_map_, stream->id()));
DCHECK(!ContainsKey(static_stream_map_, stream->id()));
dynamic_stream_map_[stream->id()] = stream;
// Increase the number of streams being emulated when a new one is opened.
connection_->SetNumOpenStreams(dynamic_stream_map_.size());
}
QuicStreamId QuicSession::GetNextStreamId() {
QuicStreamId id = next_stream_id_;
next_stream_id_ += 2;
return id;
}
ReliableQuicStream* QuicSession::GetStream(const QuicStreamId stream_id) {
StreamMap::iterator it = static_stream_map_.find(stream_id);
if (it != static_stream_map_.end()) {
return it->second;
}
return GetDynamicStream(stream_id);
}
void QuicSession::StreamDraining(QuicStreamId stream_id) {
DCHECK(ContainsKey(dynamic_stream_map_, stream_id));
if (!ContainsKey(draining_streams_, stream_id)) {
draining_streams_.insert(stream_id);
}
}
ReliableQuicStream* QuicSession::GetDynamicStream(
const QuicStreamId stream_id) {
if (static_stream_map_.find(stream_id) != static_stream_map_.end()) {
DLOG(FATAL) << "Attempt to call GetDynamicStream for a static stream";
return nullptr;
}
StreamMap::iterator it = dynamic_stream_map_.find(stream_id);
if (it != dynamic_stream_map_.end()) {
return it->second;
}
if (IsClosedStream(stream_id)) {
return nullptr;
}
if (stream_id % 2 == next_stream_id_ % 2) {
// We've received a frame for a locally-created stream that is not
// currently active. This is an error.
if (connection()->connected()) {
connection()->SendConnectionClose(QUIC_PACKET_FOR_NONEXISTENT_STREAM);
}
return nullptr;
}
return GetIncomingDynamicStream(stream_id);
}
ReliableQuicStream* QuicSession::GetIncomingDynamicStream(
QuicStreamId stream_id) {
if (IsClosedStream(stream_id)) {
return nullptr;
}
implicitly_created_streams_.erase(stream_id);
if (stream_id > largest_peer_created_stream_id_) {
if (stream_id - largest_peer_created_stream_id_ > kMaxStreamIdDelta) {
// We may already have sent a connection close due to multiple reset
// streams in the same packet.
if (connection()->connected()) {
LOG(ERROR) << "Trying to get stream: " << stream_id
<< ", largest peer created stream: "
<< largest_peer_created_stream_id_
<< ", max delta: " << kMaxStreamIdDelta;
connection()->SendConnectionClose(QUIC_INVALID_STREAM_ID);
}
return nullptr;
}
for (QuicStreamId id = largest_peer_created_stream_id_ + 2;
id < stream_id;
id += 2) {
implicitly_created_streams_.insert(id);
}
largest_peer_created_stream_id_ = stream_id;
}
ReliableQuicStream* stream = CreateIncomingDynamicStream(stream_id);
if (stream == nullptr) {
return nullptr;
}
ActivateStream(stream);
return stream;
}
void QuicSession::set_max_open_streams(size_t max_open_streams) {
DVLOG(1) << "Setting max_open_streams_ to " << max_open_streams;
max_open_streams_ = max_open_streams;
}
bool QuicSession::IsClosedStream(QuicStreamId id) {
DCHECK_NE(0u, id);
if (ContainsKey(static_stream_map_, id) ||
ContainsKey(dynamic_stream_map_, id)) {
// Stream is active
return false;
}
if (id % 2 == next_stream_id_ % 2) {
// Locally created streams are strictly in-order. If the id is in the
// range of created streams and it's not active, it must have been closed.
return id < next_stream_id_;
}
// For peer created streams, we also need to consider implicitly created
// streams.
return id <= largest_peer_created_stream_id_ &&
!ContainsKey(implicitly_created_streams_, id);
}
size_t QuicSession::GetNumOpenStreams() const {
return dynamic_stream_map_.size() + implicitly_created_streams_.size() -
draining_streams_.size();
}
void QuicSession::MarkConnectionLevelWriteBlocked(QuicStreamId id,
QuicPriority priority) {
#ifndef NDEBUG
ReliableQuicStream* stream = GetStream(id);
if (stream != nullptr) {
LOG_IF(DFATAL, priority != stream->EffectivePriority())
<< ENDPOINT << "Stream " << id
<< "Priorities do not match. Got: " << priority
<< " Expected: " << stream->EffectivePriority();
} else {
LOG(DFATAL) << "Marking unknown stream " << id << " blocked.";
}
#endif
if (id == kCryptoStreamId) {
DCHECK(!has_pending_handshake_);
has_pending_handshake_ = true;
// TODO(jar): Be sure to use the highest priority for the crypto stream,
// perhaps by adding a "special" priority for it that is higher than
// kHighestPriority.
priority = kHighestPriority;
}
write_blocked_streams_.PushBack(id, priority);
}
bool QuicSession::HasDataToWrite() const {
return write_blocked_streams_.HasWriteBlockedCryptoOrHeadersStream() ||
write_blocked_streams_.HasWriteBlockedDataStreams() ||
connection_->HasQueuedData();
}
void QuicSession::PostProcessAfterData() {
STLDeleteElements(&closed_streams_);
if (connection()->connected() &&
locally_closed_streams_highest_offset_.size() > max_open_streams_) {
// A buggy client may fail to send FIN/RSTs. Don't tolerate this.
connection_->SendConnectionClose(QUIC_TOO_MANY_UNFINISHED_STREAMS);
}
}
bool QuicSession::IsConnectionFlowControlBlocked() const {
return flow_controller_.IsBlocked();
}
bool QuicSession::IsStreamFlowControlBlocked() {
for (auto const& kv : static_stream_map_) {
if (kv.second->flow_controller()->IsBlocked()) {
return true;
}
}
for (auto const& kv : dynamic_stream_map_) {
if (kv.second->flow_controller()->IsBlocked()) {
return true;
}
}
return false;
}
} // namespace net