| // 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 "quic/core/quic_dispatcher.h" |
| |
| #include <memory> |
| #include <string> |
| #include <utility> |
| |
| #include "absl/container/flat_hash_set.h" |
| #include "absl/strings/string_view.h" |
| #include "quic/core/chlo_extractor.h" |
| #include "quic/core/crypto/crypto_protocol.h" |
| #include "quic/core/crypto/quic_random.h" |
| #include "quic/core/quic_connection_id.h" |
| #include "quic/core/quic_error_codes.h" |
| #include "quic/core/quic_session.h" |
| #include "quic/core/quic_time_wait_list_manager.h" |
| #include "quic/core/quic_types.h" |
| #include "quic/core/quic_utils.h" |
| #include "quic/core/quic_versions.h" |
| #include "quic/core/tls_chlo_extractor.h" |
| #include "quic/platform/api/quic_bug_tracker.h" |
| #include "quic/platform/api/quic_flag_utils.h" |
| #include "quic/platform/api/quic_flags.h" |
| #include "quic/platform/api/quic_logging.h" |
| #include "quic/platform/api/quic_ptr_util.h" |
| #include "quic/platform/api/quic_stack_trace.h" |
| #include "common/platform/api/quiche_text_utils.h" |
| |
| namespace quic { |
| |
| using BufferedPacket = QuicBufferedPacketStore::BufferedPacket; |
| using BufferedPacketList = QuicBufferedPacketStore::BufferedPacketList; |
| using EnqueuePacketResult = QuicBufferedPacketStore::EnqueuePacketResult; |
| |
| namespace { |
| |
| // Minimal INITIAL packet length sent by clients is 1200. |
| const QuicPacketLength kMinClientInitialPacketLength = 1200; |
| |
| // An alarm that informs the QuicDispatcher to delete old sessions. |
| class DeleteSessionsAlarm : public QuicAlarm::Delegate { |
| public: |
| explicit DeleteSessionsAlarm(QuicDispatcher* dispatcher) |
| : dispatcher_(dispatcher) {} |
| DeleteSessionsAlarm(const DeleteSessionsAlarm&) = delete; |
| DeleteSessionsAlarm& operator=(const DeleteSessionsAlarm&) = delete; |
| |
| void OnAlarm() override { dispatcher_->DeleteSessions(); } |
| |
| private: |
| // Not owned. |
| QuicDispatcher* dispatcher_; |
| }; |
| |
| // Collects packets serialized by a QuicPacketCreator in order |
| // to be handed off to the time wait list manager. |
| class PacketCollector : public QuicPacketCreator::DelegateInterface, |
| public QuicStreamFrameDataProducer { |
| public: |
| explicit PacketCollector(QuicBufferAllocator* allocator) |
| : send_buffer_(allocator) {} |
| ~PacketCollector() override = default; |
| |
| // QuicPacketCreator::DelegateInterface methods: |
| void OnSerializedPacket(SerializedPacket serialized_packet) override { |
| // Make a copy of the serialized packet to send later. |
| packets_.emplace_back( |
| new QuicEncryptedPacket(CopyBuffer(serialized_packet), |
| serialized_packet.encrypted_length, true)); |
| } |
| |
| QuicPacketBuffer GetPacketBuffer() override { |
| // Let QuicPacketCreator to serialize packets on stack buffer. |
| return {nullptr, nullptr}; |
| } |
| |
| void OnUnrecoverableError(QuicErrorCode /*error*/, |
| const std::string& /*error_details*/) override {} |
| |
| bool ShouldGeneratePacket(HasRetransmittableData /*retransmittable*/, |
| IsHandshake /*handshake*/) override { |
| QUICHE_DCHECK(false); |
| return true; |
| } |
| |
| const QuicFrames MaybeBundleAckOpportunistically() override { |
| QUICHE_DCHECK(false); |
| return {}; |
| } |
| |
| SerializedPacketFate GetSerializedPacketFate( |
| bool /*is_mtu_discovery*/, |
| EncryptionLevel /*encryption_level*/) override { |
| return SEND_TO_WRITER; |
| } |
| |
| // QuicStreamFrameDataProducer |
| WriteStreamDataResult WriteStreamData(QuicStreamId /*id*/, |
| QuicStreamOffset offset, |
| QuicByteCount data_length, |
| QuicDataWriter* writer) override { |
| if (send_buffer_.WriteStreamData(offset, data_length, writer)) { |
| return WRITE_SUCCESS; |
| } |
| return WRITE_FAILED; |
| } |
| bool WriteCryptoData(EncryptionLevel /*level*/, |
| QuicStreamOffset offset, |
| QuicByteCount data_length, |
| QuicDataWriter* writer) override { |
| return send_buffer_.WriteStreamData(offset, data_length, writer); |
| } |
| |
| std::vector<std::unique_ptr<QuicEncryptedPacket>>* packets() { |
| return &packets_; |
| } |
| |
| private: |
| std::vector<std::unique_ptr<QuicEncryptedPacket>> packets_; |
| // This is only needed until the packets are encrypted. Once packets are |
| // encrypted, the stream data is no longer required. |
| QuicStreamSendBuffer send_buffer_; |
| }; |
| |
| // Helper for statelessly closing connections by generating the |
| // correct termination packets and adding the connection to the time wait |
| // list manager. |
| class StatelessConnectionTerminator { |
| public: |
| StatelessConnectionTerminator(QuicConnectionId server_connection_id, |
| const ParsedQuicVersion version, |
| QuicConnectionHelperInterface* helper, |
| QuicTimeWaitListManager* time_wait_list_manager) |
| : server_connection_id_(server_connection_id), |
| framer_(ParsedQuicVersionVector{version}, |
| /*unused*/ QuicTime::Zero(), |
| Perspective::IS_SERVER, |
| /*unused*/ kQuicDefaultConnectionIdLength), |
| collector_(helper->GetStreamSendBufferAllocator()), |
| creator_(server_connection_id, &framer_, &collector_), |
| time_wait_list_manager_(time_wait_list_manager) { |
| framer_.set_data_producer(&collector_); |
| framer_.SetInitialObfuscators(server_connection_id); |
| } |
| |
| ~StatelessConnectionTerminator() { |
| // Clear framer's producer. |
| framer_.set_data_producer(nullptr); |
| } |
| |
| // Generates a packet containing a CONNECTION_CLOSE frame specifying |
| // |error_code| and |error_details| and add the connection to time wait. |
| void CloseConnection(QuicErrorCode error_code, |
| const std::string& error_details, |
| bool ietf_quic, |
| std::vector<QuicConnectionId> active_connection_ids) { |
| SerializeConnectionClosePacket(error_code, error_details); |
| |
| time_wait_list_manager_->AddConnectionIdToTimeWait( |
| server_connection_id_, |
| QuicTimeWaitListManager::SEND_TERMINATION_PACKETS, |
| TimeWaitConnectionInfo(ietf_quic, collector_.packets(), |
| std::move(active_connection_ids), |
| /*srtt=*/QuicTime::Delta::Zero())); |
| } |
| |
| private: |
| void SerializeConnectionClosePacket(QuicErrorCode error_code, |
| const std::string& error_details) { |
| QuicConnectionCloseFrame* frame = |
| new QuicConnectionCloseFrame(framer_.transport_version(), error_code, |
| NO_IETF_QUIC_ERROR, error_details, |
| /*transport_close_frame_type=*/0); |
| |
| if (!creator_.AddFrame(QuicFrame(frame), NOT_RETRANSMISSION)) { |
| QUIC_BUG(quic_bug_10287_1) << "Unable to add frame to an empty packet"; |
| delete frame; |
| return; |
| } |
| creator_.FlushCurrentPacket(); |
| QUICHE_DCHECK_EQ(1u, collector_.packets()->size()); |
| } |
| |
| QuicConnectionId server_connection_id_; |
| QuicFramer framer_; |
| // Set as the visitor of |creator_| to collect any generated packets. |
| PacketCollector collector_; |
| QuicPacketCreator creator_; |
| QuicTimeWaitListManager* time_wait_list_manager_; |
| }; |
| |
| // Class which extracts the ALPN from a QUIC_CRYPTO CHLO packet. |
| class ChloAlpnExtractor : public ChloExtractor::Delegate { |
| public: |
| void OnChlo(QuicTransportVersion version, |
| QuicConnectionId /*server_connection_id*/, |
| const CryptoHandshakeMessage& chlo) override { |
| absl::string_view alpn_value; |
| if (chlo.GetStringPiece(kALPN, &alpn_value)) { |
| alpn_ = std::string(alpn_value); |
| } |
| if (version == LegacyVersionForEncapsulation().transport_version) { |
| absl::string_view qlve_value; |
| if (chlo.GetStringPiece(kQLVE, &qlve_value)) { |
| legacy_version_encapsulation_inner_packet_ = std::string(qlve_value); |
| } |
| } |
| } |
| |
| std::string&& ConsumeAlpn() { return std::move(alpn_); } |
| |
| std::string&& ConsumeLegacyVersionEncapsulationInnerPacket() { |
| return std::move(legacy_version_encapsulation_inner_packet_); |
| } |
| |
| private: |
| std::string alpn_; |
| std::string legacy_version_encapsulation_inner_packet_; |
| }; |
| |
| bool MaybeHandleLegacyVersionEncapsulation( |
| QuicDispatcher* dispatcher, |
| ChloAlpnExtractor* alpn_extractor, |
| const ReceivedPacketInfo& packet_info) { |
| std::string legacy_version_encapsulation_inner_packet = |
| alpn_extractor->ConsumeLegacyVersionEncapsulationInnerPacket(); |
| if (legacy_version_encapsulation_inner_packet.empty()) { |
| // This CHLO did not contain the Legacy Version Encapsulation tag. |
| return false; |
| } |
| PacketHeaderFormat format; |
| QuicLongHeaderType long_packet_type; |
| bool version_present; |
| bool has_length_prefix; |
| QuicVersionLabel version_label; |
| ParsedQuicVersion parsed_version = ParsedQuicVersion::Unsupported(); |
| QuicConnectionId destination_connection_id, source_connection_id; |
| bool retry_token_present; |
| absl::string_view retry_token; |
| std::string detailed_error; |
| const QuicErrorCode error = QuicFramer::ParsePublicHeaderDispatcher( |
| QuicEncryptedPacket(legacy_version_encapsulation_inner_packet.data(), |
| legacy_version_encapsulation_inner_packet.length()), |
| kQuicDefaultConnectionIdLength, &format, &long_packet_type, |
| &version_present, &has_length_prefix, &version_label, &parsed_version, |
| &destination_connection_id, &source_connection_id, &retry_token_present, |
| &retry_token, &detailed_error); |
| if (error != QUIC_NO_ERROR) { |
| QUIC_DLOG(ERROR) |
| << "Failed to parse Legacy Version Encapsulation inner packet:" |
| << detailed_error; |
| return false; |
| } |
| if (destination_connection_id != packet_info.destination_connection_id) { |
| // We enforce that the inner and outer connection IDs match to make sure |
| // this never impacts routing of packets. |
| QUIC_DLOG(ERROR) << "Ignoring Legacy Version Encapsulation packet " |
| "with mismatched connection ID " |
| << destination_connection_id << " vs " |
| << packet_info.destination_connection_id; |
| return false; |
| } |
| if (legacy_version_encapsulation_inner_packet.length() >= |
| packet_info.packet.length()) { |
| QUIC_BUG(quic_bug_10287_2) |
| << "Inner packet cannot be larger than outer " |
| << legacy_version_encapsulation_inner_packet.length() << " vs " |
| << packet_info.packet.length(); |
| return false; |
| } |
| |
| QUIC_DVLOG(1) << "Extracted a Legacy Version Encapsulation " |
| << legacy_version_encapsulation_inner_packet.length() |
| << " byte packet of version " << parsed_version; |
| |
| // Append zeroes to the end of the packet. This will ensure that |
| // we use the right number of bytes for calculating anti-amplification |
| // limits. Note that this only works for long headers of versions that carry |
| // long header lengths, since they'll ignore any trailing zeroes. We still |
| // do this for all packets to ensure version negotiation works. |
| legacy_version_encapsulation_inner_packet.append( |
| packet_info.packet.length() - |
| legacy_version_encapsulation_inner_packet.length(), |
| 0x00); |
| |
| // Process the inner packet as if it had been received by itself. |
| QuicReceivedPacket received_encapsulated_packet( |
| legacy_version_encapsulation_inner_packet.data(), |
| legacy_version_encapsulation_inner_packet.length(), |
| packet_info.packet.receipt_time()); |
| dispatcher->ProcessPacket(packet_info.self_address, packet_info.peer_address, |
| received_encapsulated_packet); |
| QUIC_CODE_COUNT(quic_legacy_version_encapsulation_decapsulated); |
| return true; |
| } |
| |
| } // namespace |
| |
| QuicDispatcher::QuicDispatcher( |
| const QuicConfig* config, |
| const QuicCryptoServerConfig* crypto_config, |
| QuicVersionManager* version_manager, |
| std::unique_ptr<QuicConnectionHelperInterface> helper, |
| std::unique_ptr<QuicCryptoServerStreamBase::Helper> session_helper, |
| std::unique_ptr<QuicAlarmFactory> alarm_factory, |
| uint8_t expected_server_connection_id_length) |
| : config_(config), |
| crypto_config_(crypto_config), |
| compressed_certs_cache_( |
| QuicCompressedCertsCache::kQuicCompressedCertsCacheSize), |
| helper_(std::move(helper)), |
| session_helper_(std::move(session_helper)), |
| alarm_factory_(std::move(alarm_factory)), |
| delete_sessions_alarm_( |
| alarm_factory_->CreateAlarm(new DeleteSessionsAlarm(this))), |
| buffered_packets_(this, helper_->GetClock(), alarm_factory_.get()), |
| version_manager_(version_manager), |
| last_error_(QUIC_NO_ERROR), |
| new_sessions_allowed_per_event_loop_(0u), |
| accept_new_connections_(true), |
| allow_short_initial_server_connection_ids_(false), |
| expected_server_connection_id_length_( |
| expected_server_connection_id_length), |
| should_update_expected_server_connection_id_length_(false) { |
| if (use_reference_counted_session_map_) { |
| QUIC_RESTART_FLAG_COUNT(quic_use_reference_counted_sesssion_map); |
| } |
| QUIC_BUG_IF(quic_bug_12724_1, GetSupportedVersions().empty()) |
| << "Trying to create dispatcher without any supported versions"; |
| QUIC_DLOG(INFO) << "Created QuicDispatcher with versions: " |
| << ParsedQuicVersionVectorToString(GetSupportedVersions()); |
| } |
| |
| QuicDispatcher::~QuicDispatcher() { |
| if (use_reference_counted_session_map_) { |
| reference_counted_session_map_.clear(); |
| closed_ref_counted_session_list_.clear(); |
| if (support_multiple_cid_per_connection_) { |
| num_sessions_in_session_map_ = 0; |
| } |
| } else { |
| session_map_.clear(); |
| closed_session_list_.clear(); |
| } |
| } |
| |
| void QuicDispatcher::InitializeWithWriter(QuicPacketWriter* writer) { |
| QUICHE_DCHECK(writer_ == nullptr); |
| writer_.reset(writer); |
| time_wait_list_manager_.reset(CreateQuicTimeWaitListManager()); |
| } |
| |
| void QuicDispatcher::ProcessPacket(const QuicSocketAddress& self_address, |
| const QuicSocketAddress& peer_address, |
| const QuicReceivedPacket& packet) { |
| QUIC_DVLOG(2) << "Dispatcher received encrypted " << packet.length() |
| << " bytes:" << std::endl |
| << quiche::QuicheTextUtils::HexDump( |
| absl::string_view(packet.data(), packet.length())); |
| ReceivedPacketInfo packet_info(self_address, peer_address, packet); |
| std::string detailed_error; |
| bool retry_token_present; |
| absl::string_view retry_token; |
| const QuicErrorCode error = QuicFramer::ParsePublicHeaderDispatcher( |
| packet, expected_server_connection_id_length_, &packet_info.form, |
| &packet_info.long_packet_type, &packet_info.version_flag, |
| &packet_info.use_length_prefix, &packet_info.version_label, |
| &packet_info.version, &packet_info.destination_connection_id, |
| &packet_info.source_connection_id, &retry_token_present, &retry_token, |
| &detailed_error); |
| if (error != QUIC_NO_ERROR) { |
| // Packet has framing error. |
| SetLastError(error); |
| QUIC_DLOG(ERROR) << detailed_error; |
| return; |
| } |
| if (packet_info.destination_connection_id.length() != |
| expected_server_connection_id_length_ && |
| !should_update_expected_server_connection_id_length_ && |
| packet_info.version.IsKnown() && |
| !packet_info.version.AllowsVariableLengthConnectionIds()) { |
| SetLastError(QUIC_INVALID_PACKET_HEADER); |
| QUIC_DLOG(ERROR) << "Invalid Connection Id Length"; |
| return; |
| } |
| |
| if (packet_info.version_flag && IsSupportedVersion(packet_info.version)) { |
| if (!QuicUtils::IsConnectionIdValidForVersion( |
| packet_info.destination_connection_id, |
| packet_info.version.transport_version)) { |
| SetLastError(QUIC_INVALID_PACKET_HEADER); |
| QUIC_DLOG(ERROR) |
| << "Invalid destination connection ID length for version"; |
| return; |
| } |
| if (packet_info.version.SupportsClientConnectionIds() && |
| !QuicUtils::IsConnectionIdValidForVersion( |
| packet_info.source_connection_id, |
| packet_info.version.transport_version)) { |
| SetLastError(QUIC_INVALID_PACKET_HEADER); |
| QUIC_DLOG(ERROR) << "Invalid source connection ID length for version"; |
| return; |
| } |
| } |
| |
| if (should_update_expected_server_connection_id_length_) { |
| expected_server_connection_id_length_ = |
| packet_info.destination_connection_id.length(); |
| } |
| |
| if (MaybeDispatchPacket(packet_info)) { |
| // Packet has been dropped or successfully dispatched, stop processing. |
| return; |
| } |
| ProcessHeader(&packet_info); |
| } |
| |
| QuicConnectionId QuicDispatcher::MaybeReplaceServerConnectionId( |
| const QuicConnectionId& server_connection_id, |
| const ParsedQuicVersion& version) const { |
| const uint8_t server_connection_id_length = server_connection_id.length(); |
| if (server_connection_id_length == expected_server_connection_id_length_) { |
| return server_connection_id; |
| } |
| QUICHE_DCHECK(version.AllowsVariableLengthConnectionIds()); |
| QuicConnectionId new_connection_id; |
| if (server_connection_id_length < expected_server_connection_id_length_) { |
| new_connection_id = ReplaceShortServerConnectionId( |
| version, server_connection_id, expected_server_connection_id_length_); |
| // Verify that ReplaceShortServerConnectionId is deterministic. |
| QUICHE_DCHECK_EQ( |
| new_connection_id, |
| ReplaceShortServerConnectionId(version, server_connection_id, |
| expected_server_connection_id_length_)); |
| } else { |
| new_connection_id = ReplaceLongServerConnectionId( |
| version, server_connection_id, expected_server_connection_id_length_); |
| // Verify that ReplaceLongServerConnectionId is deterministic. |
| QUICHE_DCHECK_EQ( |
| new_connection_id, |
| ReplaceLongServerConnectionId(version, server_connection_id, |
| expected_server_connection_id_length_)); |
| } |
| QUICHE_DCHECK_EQ(expected_server_connection_id_length_, |
| new_connection_id.length()); |
| |
| QUIC_DLOG(INFO) << "Replacing incoming connection ID " << server_connection_id |
| << " with " << new_connection_id; |
| return new_connection_id; |
| } |
| |
| QuicConnectionId QuicDispatcher::ReplaceShortServerConnectionId( |
| const ParsedQuicVersion& /*version*/, |
| const QuicConnectionId& server_connection_id, |
| uint8_t expected_server_connection_id_length) const { |
| QUICHE_DCHECK_LT(server_connection_id.length(), |
| expected_server_connection_id_length); |
| return QuicUtils::CreateReplacementConnectionId( |
| server_connection_id, expected_server_connection_id_length); |
| } |
| |
| QuicConnectionId QuicDispatcher::ReplaceLongServerConnectionId( |
| const ParsedQuicVersion& /*version*/, |
| const QuicConnectionId& server_connection_id, |
| uint8_t expected_server_connection_id_length) const { |
| QUICHE_DCHECK_GT(server_connection_id.length(), |
| expected_server_connection_id_length); |
| return QuicUtils::CreateReplacementConnectionId( |
| server_connection_id, expected_server_connection_id_length); |
| } |
| |
| bool QuicDispatcher::MaybeDispatchPacket( |
| const ReceivedPacketInfo& packet_info) { |
| // Port zero is only allowed for unidirectional UDP, so is disallowed by QUIC. |
| // Given that we can't even send a reply rejecting the packet, just drop the |
| // packet. |
| if (packet_info.peer_address.port() == 0) { |
| return true; |
| } |
| |
| QuicConnectionId server_connection_id = packet_info.destination_connection_id; |
| |
| // The IETF spec requires the client to generate an initial server |
| // connection ID that is at least 64 bits long. After that initial |
| // connection ID, the dispatcher picks a new one of its expected length. |
| // Therefore we should never receive a connection ID that is smaller |
| // than 64 bits and smaller than what we expect. Unless the version is |
| // unknown, in which case we allow short connection IDs for version |
| // negotiation because that version could allow those. |
| if (packet_info.version_flag && packet_info.version.IsKnown() && |
| server_connection_id.length() < kQuicMinimumInitialConnectionIdLength && |
| server_connection_id.length() < expected_server_connection_id_length_ && |
| !allow_short_initial_server_connection_ids_) { |
| QUICHE_DCHECK(packet_info.version_flag); |
| QUICHE_DCHECK(packet_info.version.AllowsVariableLengthConnectionIds()); |
| QUIC_DLOG(INFO) << "Packet with short destination connection ID " |
| << server_connection_id << " expected " |
| << static_cast<int>(expected_server_connection_id_length_); |
| // Drop the packet silently. |
| QUIC_CODE_COUNT(quic_dropped_invalid_small_initial_connection_id); |
| return true; |
| } |
| |
| // Packets with connection IDs for active connections are processed |
| // immediately. |
| if (use_reference_counted_session_map_) { |
| auto it = reference_counted_session_map_.find(server_connection_id); |
| if (it != reference_counted_session_map_.end()) { |
| QUICHE_DCHECK( |
| !buffered_packets_.HasBufferedPackets(server_connection_id)); |
| if (packet_info.version_flag && |
| packet_info.version != it->second->version() && |
| packet_info.version == LegacyVersionForEncapsulation()) { |
| // This packet is using the Legacy Version Encapsulation version but the |
| // corresponding session isn't, attempt extraction of inner packet. |
| ChloAlpnExtractor alpn_extractor; |
| if (ChloExtractor::Extract(packet_info.packet, packet_info.version, |
| config_->create_session_tag_indicators(), |
| &alpn_extractor, |
| server_connection_id.length())) { |
| if (MaybeHandleLegacyVersionEncapsulation(this, &alpn_extractor, |
| packet_info)) { |
| return true; |
| } |
| } |
| } |
| it->second->ProcessUdpPacket(packet_info.self_address, |
| packet_info.peer_address, |
| packet_info.packet); |
| return true; |
| } |
| } else { |
| auto it = session_map_.find(server_connection_id); |
| if (it != session_map_.end()) { |
| QUICHE_DCHECK( |
| !buffered_packets_.HasBufferedPackets(server_connection_id)); |
| if (packet_info.version_flag && |
| packet_info.version != it->second->version() && |
| packet_info.version == LegacyVersionForEncapsulation()) { |
| // This packet is using the Legacy Version Encapsulation version but the |
| // corresponding session isn't, attempt extraction of inner packet. |
| ChloAlpnExtractor alpn_extractor; |
| if (ChloExtractor::Extract(packet_info.packet, packet_info.version, |
| config_->create_session_tag_indicators(), |
| &alpn_extractor, |
| server_connection_id.length())) { |
| if (MaybeHandleLegacyVersionEncapsulation(this, &alpn_extractor, |
| packet_info)) { |
| return true; |
| } |
| } |
| } |
| it->second->ProcessUdpPacket(packet_info.self_address, |
| packet_info.peer_address, |
| packet_info.packet); |
| return true; |
| } |
| } |
| if (packet_info.version.IsKnown()) { |
| // We did not find the connection ID, check if we've replaced it. |
| // This is only performed for supported versions because packets with |
| // unsupported versions can flow through this function in order to send |
| // a version negotiation packet, but we know that their connection ID |
| // did not get replaced since that is performed on connection creation, |
| // and that only happens for known verions. |
| QuicConnectionId replaced_connection_id = MaybeReplaceServerConnectionId( |
| server_connection_id, packet_info.version); |
| if (replaced_connection_id != server_connection_id) { |
| if (use_reference_counted_session_map_) { |
| // Search for the replacement. |
| auto it2 = reference_counted_session_map_.find(replaced_connection_id); |
| if (it2 != reference_counted_session_map_.end()) { |
| QUICHE_DCHECK( |
| !buffered_packets_.HasBufferedPackets(replaced_connection_id)); |
| it2->second->ProcessUdpPacket(packet_info.self_address, |
| packet_info.peer_address, |
| packet_info.packet); |
| return true; |
| } |
| } else { |
| // Search for the replacement. |
| auto it2 = session_map_.find(replaced_connection_id); |
| if (it2 != session_map_.end()) { |
| QUICHE_DCHECK( |
| !buffered_packets_.HasBufferedPackets(replaced_connection_id)); |
| it2->second->ProcessUdpPacket(packet_info.self_address, |
| packet_info.peer_address, |
| packet_info.packet); |
| return true; |
| } |
| } |
| } |
| } |
| |
| if (buffered_packets_.HasChloForConnection(server_connection_id)) { |
| BufferEarlyPacket(packet_info); |
| return true; |
| } |
| |
| if (OnFailedToDispatchPacket(packet_info)) { |
| return true; |
| } |
| |
| if (time_wait_list_manager_->IsConnectionIdInTimeWait(server_connection_id)) { |
| // This connection ID is already in time-wait state. |
| time_wait_list_manager_->ProcessPacket( |
| packet_info.self_address, packet_info.peer_address, |
| packet_info.destination_connection_id, packet_info.form, |
| packet_info.packet.length(), GetPerPacketContext()); |
| return true; |
| } |
| |
| // The packet has an unknown connection ID. |
| if (!accept_new_connections_ && packet_info.version_flag) { |
| // If not accepting new connections, reject packets with version which can |
| // potentially result in new connection creation. But if the packet doesn't |
| // have version flag, leave it to ValidityChecks() to reset it. |
| // By adding the connection to time wait list, following packets on this |
| // connection will not reach ShouldAcceptNewConnections(). |
| StatelesslyTerminateConnection( |
| packet_info.destination_connection_id, packet_info.form, |
| packet_info.version_flag, packet_info.use_length_prefix, |
| packet_info.version, QUIC_HANDSHAKE_FAILED, |
| "Stop accepting new connections", |
| quic::QuicTimeWaitListManager::SEND_STATELESS_RESET); |
| // Time wait list will reject the packet correspondingly.. |
| time_wait_list_manager()->ProcessPacket( |
| packet_info.self_address, packet_info.peer_address, |
| packet_info.destination_connection_id, packet_info.form, |
| packet_info.packet.length(), GetPerPacketContext()); |
| OnNewConnectionRejected(); |
| return true; |
| } |
| |
| // Unless the packet provides a version, assume that we can continue |
| // processing using our preferred version. |
| if (packet_info.version_flag) { |
| if (!IsSupportedVersion(packet_info.version)) { |
| if (ShouldCreateSessionForUnknownVersion(packet_info.version_label)) { |
| return false; |
| } |
| if (!crypto_config()->validate_chlo_size() || |
| packet_info.packet.length() >= kMinPacketSizeForVersionNegotiation) { |
| // Since the version is not supported, send a version negotiation |
| // packet and stop processing the current packet. |
| QuicConnectionId client_connection_id = |
| packet_info.source_connection_id; |
| time_wait_list_manager()->SendVersionNegotiationPacket( |
| server_connection_id, client_connection_id, |
| packet_info.form != GOOGLE_QUIC_PACKET, |
| packet_info.use_length_prefix, GetSupportedVersions(), |
| packet_info.self_address, packet_info.peer_address, |
| GetPerPacketContext()); |
| } |
| return true; |
| } |
| |
| if (crypto_config()->validate_chlo_size() && |
| packet_info.form == IETF_QUIC_LONG_HEADER_PACKET && |
| packet_info.long_packet_type == INITIAL && |
| packet_info.packet.length() < kMinClientInitialPacketLength) { |
| QUIC_DVLOG(1) << "Dropping initial packet which is too short, length: " |
| << packet_info.packet.length(); |
| QUIC_CODE_COUNT(quic_drop_small_initial_packets); |
| return true; |
| } |
| } |
| |
| return false; |
| } |
| |
| void QuicDispatcher::ProcessHeader(ReceivedPacketInfo* packet_info) { |
| QuicConnectionId server_connection_id = |
| packet_info->destination_connection_id; |
| // Packet's connection ID is unknown. Apply the validity checks. |
| QuicPacketFate fate = ValidityChecks(*packet_info); |
| ChloAlpnExtractor alpn_extractor; |
| switch (fate) { |
| case kFateProcess: { |
| if (packet_info->version.handshake_protocol == PROTOCOL_TLS1_3) { |
| bool has_full_tls_chlo = false; |
| std::vector<std::string> alpns; |
| if (buffered_packets_.HasBufferedPackets( |
| packet_info->destination_connection_id)) { |
| // If we already have buffered packets for this connection ID, |
| // use the associated TlsChloExtractor to parse this packet. |
| has_full_tls_chlo = |
| buffered_packets_.IngestPacketForTlsChloExtraction( |
| packet_info->destination_connection_id, packet_info->version, |
| packet_info->packet, &alpns); |
| } else { |
| // If we do not have a BufferedPacketList for this connection ID, |
| // create a single-use one to check whether this packet contains a |
| // full single-packet CHLO. |
| TlsChloExtractor tls_chlo_extractor; |
| tls_chlo_extractor.IngestPacket(packet_info->version, |
| packet_info->packet); |
| if (tls_chlo_extractor.HasParsedFullChlo()) { |
| // This packet contains a full single-packet CHLO. |
| has_full_tls_chlo = true; |
| alpns = tls_chlo_extractor.alpns(); |
| } |
| } |
| if (has_full_tls_chlo) { |
| ProcessChlo(alpns, packet_info); |
| } else { |
| // This packet does not contain a full CHLO. It could be a 0-RTT |
| // packet that arrived before the CHLO (due to loss or reordering), |
| // or it could be a fragment of a multi-packet CHLO. |
| BufferEarlyPacket(*packet_info); |
| } |
| break; |
| } |
| if (GetQuicFlag(FLAGS_quic_allow_chlo_buffering) && |
| !ChloExtractor::Extract(packet_info->packet, packet_info->version, |
| config_->create_session_tag_indicators(), |
| &alpn_extractor, |
| server_connection_id.length())) { |
| // Buffer non-CHLO packets. |
| BufferEarlyPacket(*packet_info); |
| break; |
| } |
| |
| // We only apply this check for versions that do not use the IETF |
| // invariant header because those versions are already checked in |
| // QuicDispatcher::MaybeDispatchPacket. |
| if (packet_info->version_flag && |
| !packet_info->version.HasIetfInvariantHeader() && |
| crypto_config()->validate_chlo_size() && |
| packet_info->packet.length() < kMinClientInitialPacketLength) { |
| QUIC_DVLOG(1) << "Dropping CHLO packet which is too short, length: " |
| << packet_info->packet.length(); |
| QUIC_CODE_COUNT(quic_drop_small_chlo_packets); |
| break; |
| } |
| |
| if (MaybeHandleLegacyVersionEncapsulation(this, &alpn_extractor, |
| *packet_info)) { |
| break; |
| } |
| |
| ProcessChlo({alpn_extractor.ConsumeAlpn()}, packet_info); |
| } break; |
| case kFateTimeWait: |
| // Add this connection_id to the time-wait state, to safely reject |
| // future packets. |
| QUIC_DLOG(INFO) << "Adding connection ID " << server_connection_id |
| << " to time-wait list."; |
| QUIC_CODE_COUNT(quic_reject_fate_time_wait); |
| StatelesslyTerminateConnection( |
| server_connection_id, packet_info->form, packet_info->version_flag, |
| packet_info->use_length_prefix, packet_info->version, |
| QUIC_HANDSHAKE_FAILED, "Reject connection", |
| quic::QuicTimeWaitListManager::SEND_STATELESS_RESET); |
| |
| QUICHE_DCHECK(time_wait_list_manager_->IsConnectionIdInTimeWait( |
| server_connection_id)); |
| time_wait_list_manager_->ProcessPacket( |
| packet_info->self_address, packet_info->peer_address, |
| server_connection_id, packet_info->form, packet_info->packet.length(), |
| GetPerPacketContext()); |
| |
| buffered_packets_.DiscardPackets(server_connection_id); |
| break; |
| case kFateDrop: |
| break; |
| } |
| } |
| |
| std::string QuicDispatcher::SelectAlpn(const std::vector<std::string>& alpns) { |
| if (alpns.empty()) { |
| return ""; |
| } |
| if (alpns.size() > 1u) { |
| const std::vector<std::string>& supported_alpns = |
| version_manager_->GetSupportedAlpns(); |
| for (const std::string& alpn : alpns) { |
| if (std::find(supported_alpns.begin(), supported_alpns.end(), alpn) != |
| supported_alpns.end()) { |
| return alpn; |
| } |
| } |
| } |
| return alpns[0]; |
| } |
| |
| QuicDispatcher::QuicPacketFate QuicDispatcher::ValidityChecks( |
| const ReceivedPacketInfo& packet_info) { |
| if (!packet_info.version_flag) { |
| QUIC_DLOG(INFO) |
| << "Packet without version arrived for unknown connection ID " |
| << packet_info.destination_connection_id; |
| MaybeResetPacketsWithNoVersion(packet_info); |
| return kFateDrop; |
| } |
| |
| // Let the connection parse and validate packet number. |
| return kFateProcess; |
| } |
| |
| void QuicDispatcher::CleanUpSession(QuicConnectionId server_connection_id, |
| QuicConnection* connection, |
| QuicErrorCode error, |
| const std::string& error_details, |
| ConnectionCloseSource source) { |
| write_blocked_list_.erase(connection); |
| QuicTimeWaitListManager::TimeWaitAction action = |
| QuicTimeWaitListManager::SEND_STATELESS_RESET; |
| if (connection->termination_packets() != nullptr && |
| !connection->termination_packets()->empty()) { |
| action = QuicTimeWaitListManager::SEND_CONNECTION_CLOSE_PACKETS; |
| } else { |
| if (!connection->IsHandshakeComplete()) { |
| const bool fix_dispatcher_sent_error_code = |
| GetQuicReloadableFlag(quic_fix_dispatcher_sent_error_code) && |
| source == ConnectionCloseSource::FROM_SELF; |
| // TODO(fayang): Do not serialize connection close packet if the |
| // connection is closed by the client. |
| if (fix_dispatcher_sent_error_code) { |
| QUIC_RELOADABLE_FLAG_COUNT(quic_fix_dispatcher_sent_error_code); |
| } |
| if (!connection->version().HasIetfInvariantHeader()) { |
| QUIC_CODE_COUNT(gquic_add_to_time_wait_list_with_handshake_failed); |
| } else { |
| QUIC_CODE_COUNT(quic_v44_add_to_time_wait_list_with_handshake_failed); |
| } |
| if (support_multiple_cid_per_connection_) { |
| QUIC_RESTART_FLAG_COUNT_N( |
| quic_dispatcher_support_multiple_cid_per_connection_v2, 1, 2); |
| // This serializes a connection close termination packet and adds the |
| // connection to the time wait list. |
| StatelessConnectionTerminator terminator( |
| server_connection_id, connection->version(), helper_.get(), |
| time_wait_list_manager_.get()); |
| terminator.CloseConnection( |
| fix_dispatcher_sent_error_code ? error : QUIC_HANDSHAKE_FAILED, |
| fix_dispatcher_sent_error_code |
| ? error_details |
| : "Connection is closed by server before handshake confirmed", |
| connection->version().HasIetfInvariantHeader(), |
| connection->GetActiveServerConnectionIds()); |
| } else { |
| action = QuicTimeWaitListManager::SEND_TERMINATION_PACKETS; |
| // This serializes a connection close termination packet and adds the |
| // connection to the time wait list. |
| StatelesslyTerminateConnection( |
| connection->connection_id(), |
| connection->version().HasIetfInvariantHeader() |
| ? IETF_QUIC_LONG_HEADER_PACKET |
| : GOOGLE_QUIC_PACKET, |
| /*version_flag=*/true, |
| connection->version().HasLengthPrefixedConnectionIds(), |
| connection->version(), |
| fix_dispatcher_sent_error_code ? error : QUIC_HANDSHAKE_FAILED, |
| fix_dispatcher_sent_error_code |
| ? error_details |
| : "Connection is closed by server before handshake confirmed", |
| // Although it is our intention to send termination packets, the |
| // |action| argument is not used by this call to |
| // StatelesslyTerminateConnection(). |
| action); |
| } |
| return; |
| } |
| QUIC_CODE_COUNT(quic_v44_add_to_time_wait_list_with_stateless_reset); |
| } |
| time_wait_list_manager_->AddConnectionIdToTimeWait( |
| server_connection_id, action, |
| TimeWaitConnectionInfo( |
| connection->version().HasIetfInvariantHeader(), |
| connection->termination_packets(), |
| connection->GetActiveServerConnectionIds(), |
| connection->sent_packet_manager().GetRttStats()->smoothed_rtt())); |
| } |
| |
| void QuicDispatcher::StartAcceptingNewConnections() { |
| accept_new_connections_ = true; |
| } |
| |
| void QuicDispatcher::StopAcceptingNewConnections() { |
| accept_new_connections_ = false; |
| // No more CHLO will arrive and buffered CHLOs shouldn't be able to create |
| // connections. |
| buffered_packets_.DiscardAllPackets(); |
| } |
| |
| void QuicDispatcher::PerformActionOnActiveSessions( |
| std::function<void(QuicSession*)> operation) const { |
| if (use_reference_counted_session_map_) { |
| absl::flat_hash_set<QuicSession*> visited_session; |
| visited_session.reserve(reference_counted_session_map_.size()); |
| for (auto const& kv : reference_counted_session_map_) { |
| QuicSession* session = kv.second.get(); |
| if (visited_session.insert(session).second) { |
| operation(session); |
| } |
| } |
| } else { |
| for (auto const& kv : session_map_) { |
| operation(kv.second.get()); |
| } |
| } |
| } |
| |
| // Get a snapshot of all sessions. |
| std::vector<std::shared_ptr<QuicSession>> QuicDispatcher::GetSessionsSnapshot() |
| const { |
| QUICHE_DCHECK(use_reference_counted_session_map_); |
| std::vector<std::shared_ptr<QuicSession>> snapshot; |
| snapshot.reserve(reference_counted_session_map_.size()); |
| absl::flat_hash_set<QuicSession*> visited_session; |
| visited_session.reserve(reference_counted_session_map_.size()); |
| for (auto const& kv : reference_counted_session_map_) { |
| QuicSession* session = kv.second.get(); |
| if (visited_session.insert(session).second) { |
| snapshot.push_back(kv.second); |
| } |
| } |
| return snapshot; |
| } |
| |
| std::unique_ptr<QuicPerPacketContext> QuicDispatcher::GetPerPacketContext() |
| const { |
| return nullptr; |
| } |
| |
| void QuicDispatcher::DeleteSessions() { |
| if (use_reference_counted_session_map_) { |
| if (!write_blocked_list_.empty()) { |
| for (const auto& session : closed_ref_counted_session_list_) { |
| if (write_blocked_list_.erase(session->connection()) != 0) { |
| QUIC_BUG(quic_bug_12724_2) |
| << "QuicConnection was in WriteBlockedList before destruction " |
| << session->connection()->connection_id(); |
| } |
| } |
| } |
| closed_ref_counted_session_list_.clear(); |
| } else { |
| if (!write_blocked_list_.empty()) { |
| for (const std::unique_ptr<QuicSession>& session : closed_session_list_) { |
| if (write_blocked_list_.erase(session->connection()) != 0) { |
| QUIC_BUG(quic_bug_12724_3) |
| << "QuicConnection was in WriteBlockedList before destruction " |
| << session->connection()->connection_id(); |
| } |
| } |
| } |
| closed_session_list_.clear(); |
| } |
| } |
| |
| void QuicDispatcher::OnCanWrite() { |
| // The socket is now writable. |
| writer_->SetWritable(); |
| |
| // Move every blocked writer in |write_blocked_list_| to a temporary list. |
| const size_t num_blocked_writers_before = write_blocked_list_.size(); |
| WriteBlockedList temp_list; |
| temp_list.swap(write_blocked_list_); |
| QUICHE_DCHECK(write_blocked_list_.empty()); |
| |
| // Give each blocked writer a chance to write what they indended to write. |
| // If they are blocked again, they will call |OnWriteBlocked| to add |
| // themselves back into |write_blocked_list_|. |
| while (!temp_list.empty()) { |
| QuicBlockedWriterInterface* blocked_writer = temp_list.begin()->first; |
| temp_list.erase(temp_list.begin()); |
| blocked_writer->OnBlockedWriterCanWrite(); |
| } |
| const size_t num_blocked_writers_after = write_blocked_list_.size(); |
| if (num_blocked_writers_after != 0) { |
| if (num_blocked_writers_before == num_blocked_writers_after) { |
| QUIC_CODE_COUNT(quic_zero_progress_on_can_write); |
| } else { |
| QUIC_CODE_COUNT(quic_blocked_again_on_can_write); |
| } |
| } |
| } |
| |
| bool QuicDispatcher::HasPendingWrites() const { |
| return !write_blocked_list_.empty(); |
| } |
| |
| void QuicDispatcher::Shutdown() { |
| if (use_reference_counted_session_map_) { |
| while (!reference_counted_session_map_.empty()) { |
| QuicSession* session = |
| reference_counted_session_map_.begin()->second.get(); |
| session->connection()->CloseConnection( |
| QUIC_PEER_GOING_AWAY, "Server shutdown imminent", |
| ConnectionCloseBehavior::SEND_CONNECTION_CLOSE_PACKET); |
| // Validate that the session removes itself from the session map on close. |
| QUICHE_DCHECK(reference_counted_session_map_.empty() || |
| reference_counted_session_map_.begin()->second.get() != |
| session); |
| } |
| } else { |
| while (!session_map_.empty()) { |
| QuicSession* session = session_map_.begin()->second.get(); |
| session->connection()->CloseConnection( |
| QUIC_PEER_GOING_AWAY, "Server shutdown imminent", |
| ConnectionCloseBehavior::SEND_CONNECTION_CLOSE_PACKET); |
| // Validate that the session removes itself from the session map on close. |
| QUICHE_DCHECK(session_map_.empty() || |
| session_map_.begin()->second.get() != session); |
| } |
| } |
| DeleteSessions(); |
| } |
| |
| void QuicDispatcher::OnConnectionClosed(QuicConnectionId server_connection_id, |
| QuicErrorCode error, |
| const std::string& error_details, |
| ConnectionCloseSource source) { |
| if (use_reference_counted_session_map_) { |
| auto it = reference_counted_session_map_.find(server_connection_id); |
| if (it == reference_counted_session_map_.end()) { |
| QUIC_BUG(quic_bug_10287_3) |
| << "ConnectionId " << server_connection_id |
| << " does not exist in the session map. Error: " |
| << QuicErrorCodeToString(error); |
| QUIC_BUG(quic_bug_10287_4) << QuicStackTrace(); |
| return; |
| } |
| |
| QUIC_DLOG_IF(INFO, error != QUIC_NO_ERROR) |
| << "Closing connection (" << server_connection_id |
| << ") due to error: " << QuicErrorCodeToString(error) |
| << ", with details: " << error_details; |
| |
| QuicConnection* connection = it->second->connection(); |
| if (ShouldDestroySessionAsynchronously()) { |
| // Set up alarm to fire immediately to bring destruction of this session |
| // out of current call stack. |
| if (closed_ref_counted_session_list_.empty()) { |
| delete_sessions_alarm_->Update(helper()->GetClock()->ApproximateNow(), |
| QuicTime::Delta::Zero()); |
| } |
| closed_ref_counted_session_list_.push_back(std::move(it->second)); |
| } |
| CleanUpSession(it->first, connection, error, error_details, source); |
| if (support_multiple_cid_per_connection_) { |
| QUIC_RESTART_FLAG_COUNT_N( |
| quic_dispatcher_support_multiple_cid_per_connection_v2, 1, 2); |
| for (const QuicConnectionId& cid : |
| connection->GetActiveServerConnectionIds()) { |
| reference_counted_session_map_.erase(cid); |
| } |
| --num_sessions_in_session_map_; |
| } else { |
| reference_counted_session_map_.erase(it); |
| } |
| } else { |
| auto it = session_map_.find(server_connection_id); |
| if (it == session_map_.end()) { |
| QUIC_BUG(quic_bug_10287_5) |
| << "ConnectionId " << server_connection_id |
| << " does not exist in the session map. Error: " |
| << QuicErrorCodeToString(error); |
| QUIC_BUG(quic_bug_10287_6) << QuicStackTrace(); |
| return; |
| } |
| |
| QUIC_DLOG_IF(INFO, error != QUIC_NO_ERROR) |
| << "Closing connection (" << server_connection_id |
| << ") due to error: " << QuicErrorCodeToString(error) |
| << ", with details: " << error_details; |
| |
| QuicConnection* connection = it->second->connection(); |
| if (ShouldDestroySessionAsynchronously()) { |
| // Set up alarm to fire immediately to bring destruction of this session |
| // out of current call stack. |
| if (closed_session_list_.empty()) { |
| delete_sessions_alarm_->Update(helper()->GetClock()->ApproximateNow(), |
| QuicTime::Delta::Zero()); |
| } |
| closed_session_list_.push_back(std::move(it->second)); |
| } |
| CleanUpSession(it->first, connection, error, error_details, source); |
| session_map_.erase(it); |
| } |
| } |
| |
| void QuicDispatcher::OnWriteBlocked( |
| QuicBlockedWriterInterface* blocked_writer) { |
| if (!blocked_writer->IsWriterBlocked()) { |
| // It is a programming error if this ever happens. When we are sure it is |
| // not happening, replace it with a QUICHE_DCHECK. |
| QUIC_BUG(quic_bug_12724_4) |
| << "Tried to add writer into blocked list when it shouldn't be added"; |
| // Return without adding the connection to the blocked list, to avoid |
| // infinite loops in OnCanWrite. |
| return; |
| } |
| |
| write_blocked_list_.insert(std::make_pair(blocked_writer, true)); |
| } |
| |
| void QuicDispatcher::OnRstStreamReceived(const QuicRstStreamFrame& /*frame*/) {} |
| |
| void QuicDispatcher::OnStopSendingReceived( |
| const QuicStopSendingFrame& /*frame*/) {} |
| |
| void QuicDispatcher::OnNewConnectionIdSent( |
| const QuicConnectionId& server_connection_id, |
| const QuicConnectionId& new_connection_id) { |
| QUICHE_DCHECK(support_multiple_cid_per_connection_); |
| auto it = reference_counted_session_map_.find(server_connection_id); |
| if (it == reference_counted_session_map_.end()) { |
| QUIC_BUG(quic_bug_10287_7) |
| << "Couldn't locate the session that issues the connection ID in " |
| "reference_counted_session_map_. server_connection_id:" |
| << server_connection_id << " new_connection_id: " << new_connection_id; |
| return; |
| } |
| auto insertion_result = reference_counted_session_map_.insert( |
| std::make_pair(new_connection_id, it->second)); |
| QUICHE_DCHECK(insertion_result.second); |
| } |
| |
| void QuicDispatcher::OnConnectionIdRetired( |
| const QuicConnectionId& server_connection_id) { |
| QUICHE_DCHECK(support_multiple_cid_per_connection_); |
| reference_counted_session_map_.erase(server_connection_id); |
| } |
| |
| void QuicDispatcher::OnConnectionAddedToTimeWaitList( |
| QuicConnectionId server_connection_id) { |
| QUIC_DLOG(INFO) << "Connection " << server_connection_id |
| << " added to time wait list."; |
| } |
| |
| void QuicDispatcher::StatelesslyTerminateConnection( |
| QuicConnectionId server_connection_id, |
| PacketHeaderFormat format, |
| bool version_flag, |
| bool use_length_prefix, |
| ParsedQuicVersion version, |
| QuicErrorCode error_code, |
| const std::string& error_details, |
| QuicTimeWaitListManager::TimeWaitAction action) { |
| if (format != IETF_QUIC_LONG_HEADER_PACKET && !version_flag) { |
| QUIC_DVLOG(1) << "Statelessly terminating " << server_connection_id |
| << " based on a non-ietf-long packet, action:" << action |
| << ", error_code:" << error_code |
| << ", error_details:" << error_details; |
| time_wait_list_manager_->AddConnectionIdToTimeWait( |
| server_connection_id, action, |
| TimeWaitConnectionInfo(format != GOOGLE_QUIC_PACKET, nullptr, |
| {server_connection_id})); |
| return; |
| } |
| |
| // If the version is known and supported by framer, send a connection close. |
| if (IsSupportedVersion(version)) { |
| QUIC_DVLOG(1) |
| << "Statelessly terminating " << server_connection_id |
| << " based on an ietf-long packet, which has a supported version:" |
| << version << ", error_code:" << error_code |
| << ", error_details:" << error_details; |
| |
| StatelessConnectionTerminator terminator(server_connection_id, version, |
| helper_.get(), |
| time_wait_list_manager_.get()); |
| // This also adds the connection to time wait list. |
| terminator.CloseConnection( |
| error_code, error_details, format != GOOGLE_QUIC_PACKET, |
| /*active_connection_ids=*/{server_connection_id}); |
| QUIC_CODE_COUNT(quic_dispatcher_generated_connection_close); |
| QuicSession::RecordConnectionCloseAtServer( |
| error_code, ConnectionCloseSource::FROM_SELF); |
| return; |
| } |
| |
| QUIC_DVLOG(1) |
| << "Statelessly terminating " << server_connection_id |
| << " based on an ietf-long packet, which has an unsupported version:" |
| << version << ", error_code:" << error_code |
| << ", error_details:" << error_details; |
| // Version is unknown or unsupported by framer, send a version negotiation |
| // with an empty version list, which can be understood by the client. |
| std::vector<std::unique_ptr<QuicEncryptedPacket>> termination_packets; |
| termination_packets.push_back(QuicFramer::BuildVersionNegotiationPacket( |
| server_connection_id, EmptyQuicConnectionId(), |
| /*ietf_quic=*/format != GOOGLE_QUIC_PACKET, use_length_prefix, |
| /*versions=*/{})); |
| time_wait_list_manager()->AddConnectionIdToTimeWait( |
| server_connection_id, QuicTimeWaitListManager::SEND_TERMINATION_PACKETS, |
| TimeWaitConnectionInfo(/*ietf_quic=*/format != GOOGLE_QUIC_PACKET, |
| &termination_packets, {server_connection_id})); |
| } |
| |
| bool QuicDispatcher::ShouldCreateSessionForUnknownVersion( |
| QuicVersionLabel /*version_label*/) { |
| return false; |
| } |
| |
| void QuicDispatcher::OnExpiredPackets( |
| QuicConnectionId server_connection_id, |
| BufferedPacketList early_arrived_packets) { |
| QUIC_CODE_COUNT(quic_reject_buffered_packets_expired); |
| StatelesslyTerminateConnection( |
| server_connection_id, |
| early_arrived_packets.ietf_quic ? IETF_QUIC_LONG_HEADER_PACKET |
| : GOOGLE_QUIC_PACKET, |
| /*version_flag=*/true, |
| early_arrived_packets.version.HasLengthPrefixedConnectionIds(), |
| early_arrived_packets.version, QUIC_HANDSHAKE_FAILED, |
| "Packets buffered for too long", |
| quic::QuicTimeWaitListManager::SEND_STATELESS_RESET); |
| } |
| |
| void QuicDispatcher::ProcessBufferedChlos(size_t max_connections_to_create) { |
| // Reset the counter before starting creating connections. |
| new_sessions_allowed_per_event_loop_ = max_connections_to_create; |
| for (; new_sessions_allowed_per_event_loop_ > 0; |
| --new_sessions_allowed_per_event_loop_) { |
| QuicConnectionId server_connection_id; |
| BufferedPacketList packet_list = |
| buffered_packets_.DeliverPacketsForNextConnection( |
| &server_connection_id); |
| const std::list<BufferedPacket>& packets = packet_list.buffered_packets; |
| if (packets.empty()) { |
| return; |
| } |
| QuicConnectionId original_connection_id = server_connection_id; |
| server_connection_id = MaybeReplaceServerConnectionId(server_connection_id, |
| packet_list.version); |
| std::string alpn = SelectAlpn(packet_list.alpns); |
| std::unique_ptr<QuicSession> session = CreateQuicSession( |
| server_connection_id, packets.front().self_address, |
| packets.front().peer_address, alpn, packet_list.version); |
| if (original_connection_id != server_connection_id) { |
| session->connection()->SetOriginalDestinationConnectionId( |
| original_connection_id); |
| } |
| QUIC_DLOG(INFO) << "Created new session for " << server_connection_id; |
| |
| if (use_reference_counted_session_map_) { |
| auto insertion_result = reference_counted_session_map_.insert( |
| std::make_pair(server_connection_id, |
| std::shared_ptr<QuicSession>(std::move(session)))); |
| if (!insertion_result.second) { |
| QUIC_BUG(quic_bug_12724_5) |
| << "Tried to add a session to session_map with existing connection " |
| "id: " |
| << server_connection_id; |
| } else if (support_multiple_cid_per_connection_) { |
| ++num_sessions_in_session_map_; |
| } |
| DeliverPacketsToSession(packets, insertion_result.first->second.get()); |
| } else { |
| auto insertion_result = session_map_.insert( |
| std::make_pair(server_connection_id, std::move(session))); |
| QUIC_BUG_IF(quic_bug_12724_6, !insertion_result.second) |
| << "Tried to add a session to session_map with existing connection " |
| "id: " |
| << server_connection_id; |
| DeliverPacketsToSession(packets, insertion_result.first->second.get()); |
| } |
| } |
| } |
| |
| bool QuicDispatcher::HasChlosBuffered() const { |
| return buffered_packets_.HasChlosBuffered(); |
| } |
| |
| bool QuicDispatcher::ShouldCreateOrBufferPacketForConnection( |
| const ReceivedPacketInfo& packet_info) { |
| QUIC_VLOG(1) << "Received packet from new connection " |
| << packet_info.destination_connection_id; |
| return true; |
| } |
| |
| // Return true if there is any packet buffered in the store. |
| bool QuicDispatcher::HasBufferedPackets(QuicConnectionId server_connection_id) { |
| return buffered_packets_.HasBufferedPackets(server_connection_id); |
| } |
| |
| void QuicDispatcher::OnBufferPacketFailure( |
| EnqueuePacketResult result, |
| QuicConnectionId server_connection_id) { |
| QUIC_DLOG(INFO) << "Fail to buffer packet on connection " |
| << server_connection_id << " because of " << result; |
| } |
| |
| QuicTimeWaitListManager* QuicDispatcher::CreateQuicTimeWaitListManager() { |
| return new QuicTimeWaitListManager(writer_.get(), this, helper_->GetClock(), |
| alarm_factory_.get()); |
| } |
| |
| void QuicDispatcher::BufferEarlyPacket(const ReceivedPacketInfo& packet_info) { |
| bool is_new_connection = !buffered_packets_.HasBufferedPackets( |
| packet_info.destination_connection_id); |
| if (is_new_connection && |
| !ShouldCreateOrBufferPacketForConnection(packet_info)) { |
| return; |
| } |
| |
| EnqueuePacketResult rs = buffered_packets_.EnqueuePacket( |
| packet_info.destination_connection_id, |
| packet_info.form != GOOGLE_QUIC_PACKET, packet_info.packet, |
| packet_info.self_address, packet_info.peer_address, /*is_chlo=*/false, |
| /*alpns=*/{}, packet_info.version); |
| if (rs != EnqueuePacketResult::SUCCESS) { |
| OnBufferPacketFailure(rs, packet_info.destination_connection_id); |
| } |
| } |
| |
| void QuicDispatcher::ProcessChlo(const std::vector<std::string>& alpns, |
| ReceivedPacketInfo* packet_info) { |
| if (!buffered_packets_.HasBufferedPackets( |
| packet_info->destination_connection_id) && |
| !ShouldCreateOrBufferPacketForConnection(*packet_info)) { |
| return; |
| } |
| if (GetQuicFlag(FLAGS_quic_allow_chlo_buffering) && |
| new_sessions_allowed_per_event_loop_ <= 0) { |
| // Can't create new session any more. Wait till next event loop. |
| QUIC_BUG_IF(quic_bug_12724_7, buffered_packets_.HasChloForConnection( |
| packet_info->destination_connection_id)); |
| EnqueuePacketResult rs = buffered_packets_.EnqueuePacket( |
| packet_info->destination_connection_id, |
| packet_info->form != GOOGLE_QUIC_PACKET, packet_info->packet, |
| packet_info->self_address, packet_info->peer_address, |
| /*is_chlo=*/true, alpns, packet_info->version); |
| if (rs != EnqueuePacketResult::SUCCESS) { |
| OnBufferPacketFailure(rs, packet_info->destination_connection_id); |
| } |
| return; |
| } |
| |
| QuicConnectionId original_connection_id = |
| packet_info->destination_connection_id; |
| packet_info->destination_connection_id = MaybeReplaceServerConnectionId( |
| original_connection_id, packet_info->version); |
| // Creates a new session and process all buffered packets for this connection. |
| std::string alpn = SelectAlpn(alpns); |
| std::unique_ptr<QuicSession> session = CreateQuicSession( |
| packet_info->destination_connection_id, packet_info->self_address, |
| packet_info->peer_address, alpn, packet_info->version); |
| if (QUIC_PREDICT_FALSE(session == nullptr)) { |
| QUIC_BUG(quic_bug_10287_8) |
| << "CreateQuicSession returned nullptr for " |
| << packet_info->destination_connection_id << " from " |
| << packet_info->peer_address << " to " << packet_info->self_address |
| << " ALPN \"" << alpn << "\" version " << packet_info->version; |
| return; |
| } |
| if (original_connection_id != packet_info->destination_connection_id) { |
| session->connection()->SetOriginalDestinationConnectionId( |
| original_connection_id); |
| } |
| QUIC_DLOG(INFO) << "Created new session for " |
| << packet_info->destination_connection_id; |
| |
| QuicSession* session_ptr; |
| if (use_reference_counted_session_map_) { |
| auto insertion_result = |
| reference_counted_session_map_.insert(std::make_pair( |
| packet_info->destination_connection_id, |
| std::shared_ptr<QuicSession>(std::move(session.release())))); |
| if (!insertion_result.second) { |
| QUIC_BUG(quic_bug_10287_9) |
| << "Tried to add a session to session_map with existing " |
| "connection id: " |
| << packet_info->destination_connection_id; |
| } else if (support_multiple_cid_per_connection_) { |
| ++num_sessions_in_session_map_; |
| } |
| session_ptr = insertion_result.first->second.get(); |
| } else { |
| auto insertion_result = session_map_.insert(std::make_pair( |
| packet_info->destination_connection_id, std::move(session))); |
| QUIC_BUG_IF(quic_bug_12724_8, !insertion_result.second) |
| << "Tried to add a session to session_map with existing connection id: " |
| << packet_info->destination_connection_id; |
| session_ptr = insertion_result.first->second.get(); |
| } |
| std::list<BufferedPacket> packets = |
| buffered_packets_.DeliverPackets(packet_info->destination_connection_id) |
| .buffered_packets; |
| // Process CHLO at first. |
| session_ptr->ProcessUdpPacket(packet_info->self_address, |
| packet_info->peer_address, packet_info->packet); |
| // Deliver queued-up packets in the same order as they arrived. |
| // Do this even when flag is off because there might be still some packets |
| // buffered in the store before flag is turned off. |
| DeliverPacketsToSession(packets, session_ptr); |
| --new_sessions_allowed_per_event_loop_; |
| } |
| |
| bool QuicDispatcher::ShouldDestroySessionAsynchronously() { |
| return true; |
| } |
| |
| void QuicDispatcher::SetLastError(QuicErrorCode error) { |
| last_error_ = error; |
| } |
| |
| bool QuicDispatcher::OnFailedToDispatchPacket( |
| const ReceivedPacketInfo& /*packet_info*/) { |
| return false; |
| } |
| |
| const ParsedQuicVersionVector& QuicDispatcher::GetSupportedVersions() { |
| return version_manager_->GetSupportedVersions(); |
| } |
| |
| const ParsedQuicVersionVector& |
| QuicDispatcher::GetSupportedVersionsWithQuicCrypto() { |
| return version_manager_->GetSupportedVersionsWithQuicCrypto(); |
| } |
| |
| void QuicDispatcher::DeliverPacketsToSession( |
| const std::list<BufferedPacket>& packets, |
| QuicSession* session) { |
| for (const BufferedPacket& packet : packets) { |
| session->ProcessUdpPacket(packet.self_address, packet.peer_address, |
| *(packet.packet)); |
| } |
| } |
| |
| bool QuicDispatcher::IsSupportedVersion(const ParsedQuicVersion version) { |
| for (const ParsedQuicVersion& supported_version : |
| version_manager_->GetSupportedVersions()) { |
| if (version == supported_version) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| void QuicDispatcher::MaybeResetPacketsWithNoVersion( |
| const ReceivedPacketInfo& packet_info) { |
| QUICHE_DCHECK(!packet_info.version_flag); |
| if (GetQuicReloadableFlag(quic_fix_stateless_reset) && |
| packet_info.form != GOOGLE_QUIC_PACKET) { |
| // Drop IETF packets smaller than the minimal stateless reset length. |
| if (packet_info.packet.length() <= |
| QuicFramer::GetMinStatelessResetPacketLength()) { |
| QUIC_CODE_COUNT(quic_drop_too_small_short_header_packets); |
| return; |
| } |
| } else { |
| const size_t MinValidPacketLength = |
| kPacketHeaderTypeSize + expected_server_connection_id_length_ + |
| PACKET_1BYTE_PACKET_NUMBER + /*payload size=*/1 + /*tag size=*/12; |
| if (packet_info.packet.length() < MinValidPacketLength) { |
| // The packet size is too small. |
| QUIC_CODE_COUNT(drop_too_small_packets); |
| return; |
| } |
| // TODO(fayang): Consider rate limiting reset packets if reset packet size > |
| // packet_length. |
| } |
| |
| time_wait_list_manager()->SendPublicReset( |
| packet_info.self_address, packet_info.peer_address, |
| packet_info.destination_connection_id, |
| packet_info.form != GOOGLE_QUIC_PACKET, packet_info.packet.length(), |
| GetPerPacketContext()); |
| } |
| |
| size_t QuicDispatcher::NumSessions() const { |
| if (support_multiple_cid_per_connection_) { |
| return num_sessions_in_session_map_; |
| } |
| return use_reference_counted_session_map_ |
| ? reference_counted_session_map_.size() |
| : session_map_.size(); |
| } |
| |
| } // namespace quic |
