| // 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/third_party/quiche/src/quic/core/quic_packet_creator.h" |
| |
| #include <algorithm> |
| #include <cstdint> |
| #include <string> |
| |
| #include "net/third_party/quiche/src/quic/core/crypto/crypto_protocol.h" |
| #include "net/third_party/quiche/src/quic/core/quic_connection_id.h" |
| #include "net/third_party/quiche/src/quic/core/quic_constants.h" |
| #include "net/third_party/quiche/src/quic/core/quic_data_writer.h" |
| #include "net/third_party/quiche/src/quic/core/quic_types.h" |
| #include "net/third_party/quiche/src/quic/core/quic_utils.h" |
| #include "net/third_party/quiche/src/quic/core/quic_versions.h" |
| #include "net/third_party/quiche/src/quic/platform/api/quic_aligned.h" |
| #include "net/third_party/quiche/src/quic/platform/api/quic_arraysize.h" |
| #include "net/third_party/quiche/src/quic/platform/api/quic_bug_tracker.h" |
| #include "net/third_party/quiche/src/quic/platform/api/quic_flag_utils.h" |
| #include "net/third_party/quiche/src/quic/platform/api/quic_flags.h" |
| #include "net/third_party/quiche/src/quic/platform/api/quic_logging.h" |
| #include "net/third_party/quiche/src/quic/platform/api/quic_ptr_util.h" |
| #include "net/third_party/quiche/src/quic/platform/api/quic_str_cat.h" |
| #include "net/third_party/quiche/src/quic/platform/api/quic_string_piece.h" |
| #include "net/third_party/quiche/src/quic/platform/api/quic_text_utils.h" |
| |
| namespace quic { |
| namespace { |
| |
| QuicLongHeaderType EncryptionlevelToLongHeaderType(EncryptionLevel level) { |
| switch (level) { |
| case ENCRYPTION_INITIAL: |
| return INITIAL; |
| case ENCRYPTION_HANDSHAKE: |
| return HANDSHAKE; |
| case ENCRYPTION_ZERO_RTT: |
| return ZERO_RTT_PROTECTED; |
| case ENCRYPTION_FORWARD_SECURE: |
| QUIC_BUG |
| << "Try to derive long header type for packet with encryption level: " |
| << QuicUtils::EncryptionLevelToString(level); |
| return INVALID_PACKET_TYPE; |
| default: |
| QUIC_BUG << QuicUtils::EncryptionLevelToString(level); |
| return INVALID_PACKET_TYPE; |
| } |
| } |
| |
| } // namespace |
| |
| #define ENDPOINT \ |
| (framer_->perspective() == Perspective::IS_SERVER ? "Server: " : "Client: ") |
| |
| QuicPacketCreator::QuicPacketCreator(QuicConnectionId server_connection_id, |
| QuicFramer* framer, |
| DelegateInterface* delegate) |
| : QuicPacketCreator(server_connection_id, |
| framer, |
| QuicRandom::GetInstance(), |
| delegate) {} |
| |
| QuicPacketCreator::QuicPacketCreator(QuicConnectionId server_connection_id, |
| QuicFramer* framer, |
| QuicRandom* random, |
| DelegateInterface* delegate) |
| : delegate_(delegate), |
| debug_delegate_(nullptr), |
| framer_(framer), |
| random_(random), |
| send_version_in_packet_(framer->perspective() == Perspective::IS_CLIENT), |
| have_diversification_nonce_(false), |
| max_packet_length_(0), |
| server_connection_id_included_(CONNECTION_ID_PRESENT), |
| packet_size_(0), |
| server_connection_id_(server_connection_id), |
| client_connection_id_(EmptyQuicConnectionId()), |
| packet_(QuicPacketNumber(), |
| PACKET_1BYTE_PACKET_NUMBER, |
| nullptr, |
| 0, |
| false, |
| false), |
| pending_padding_bytes_(0), |
| needs_full_padding_(false), |
| can_set_transmission_type_(false) { |
| SetMaxPacketLength(kDefaultMaxPacketSize); |
| } |
| |
| QuicPacketCreator::~QuicPacketCreator() { |
| DeleteFrames(&packet_.retransmittable_frames); |
| } |
| |
| void QuicPacketCreator::SetEncrypter(EncryptionLevel level, |
| std::unique_ptr<QuicEncrypter> encrypter) { |
| framer_->SetEncrypter(level, std::move(encrypter)); |
| max_plaintext_size_ = framer_->GetMaxPlaintextSize(max_packet_length_); |
| } |
| |
| bool QuicPacketCreator::CanSetMaxPacketLength() const { |
| // |max_packet_length_| should not be changed mid-packet. |
| return queued_frames_.empty(); |
| } |
| |
| void QuicPacketCreator::SetMaxPacketLength(QuicByteCount length) { |
| DCHECK(CanSetMaxPacketLength()); |
| |
| // Avoid recomputing |max_plaintext_size_| if the length does not actually |
| // change. |
| if (length == max_packet_length_) { |
| return; |
| } |
| |
| max_packet_length_ = length; |
| max_plaintext_size_ = framer_->GetMaxPlaintextSize(max_packet_length_); |
| QUIC_BUG_IF(max_plaintext_size_ - PacketHeaderSize() < |
| MinPlaintextPacketSize(framer_->version())) |
| << "Attempted to set max packet length too small"; |
| } |
| |
| // Stops serializing version of the protocol in packets sent after this call. |
| // A packet that is already open might send kQuicVersionSize bytes less than the |
| // maximum packet size if we stop sending version before it is serialized. |
| void QuicPacketCreator::StopSendingVersion() { |
| DCHECK(send_version_in_packet_); |
| DCHECK(!VersionHasIetfInvariantHeader(framer_->transport_version())); |
| send_version_in_packet_ = false; |
| if (packet_size_ > 0) { |
| DCHECK_LT(kQuicVersionSize, packet_size_); |
| packet_size_ -= kQuicVersionSize; |
| } |
| } |
| |
| void QuicPacketCreator::SetDiversificationNonce( |
| const DiversificationNonce& nonce) { |
| DCHECK(!have_diversification_nonce_); |
| have_diversification_nonce_ = true; |
| diversification_nonce_ = nonce; |
| } |
| |
| void QuicPacketCreator::UpdatePacketNumberLength( |
| QuicPacketNumber least_packet_awaited_by_peer, |
| QuicPacketCount max_packets_in_flight) { |
| if (!queued_frames_.empty()) { |
| // Don't change creator state if there are frames queued. |
| QUIC_BUG << "Called UpdatePacketNumberLength with " << queued_frames_.size() |
| << " queued_frames. First frame type:" |
| << queued_frames_.front().type |
| << " last frame type:" << queued_frames_.back().type; |
| return; |
| } |
| |
| DCHECK_LE(least_packet_awaited_by_peer, packet_.packet_number + 1); |
| const uint64_t current_delta = |
| packet_.packet_number + 1 - least_packet_awaited_by_peer; |
| const uint64_t delta = std::max(current_delta, max_packets_in_flight); |
| packet_.packet_number_length = QuicFramer::GetMinPacketNumberLength( |
| framer_->transport_version(), QuicPacketNumber(delta * 4)); |
| } |
| |
| bool QuicPacketCreator::ConsumeCryptoData(EncryptionLevel level, |
| size_t write_length, |
| QuicStreamOffset offset, |
| bool needs_full_padding, |
| TransmissionType transmission_type, |
| QuicFrame* frame) { |
| if (!CreateCryptoFrame(level, write_length, offset, frame)) { |
| return false; |
| } |
| // When crypto data was sent in stream frames, ConsumeData is called with |
| // |needs_full_padding = true|. Keep the same behavior here when sending |
| // crypto frames. |
| // |
| // TODO(nharper): Check what the IETF drafts say about padding out initial |
| // messages and change this as appropriate. |
| if (needs_full_padding) { |
| needs_full_padding_ = true; |
| } |
| return AddFrame(*frame, /*save_retransmittable_frames*/ true, |
| transmission_type); |
| } |
| |
| bool QuicPacketCreator::ConsumeData(QuicStreamId id, |
| size_t data_size, |
| QuicStreamOffset offset, |
| bool fin, |
| bool needs_full_padding, |
| TransmissionType transmission_type, |
| QuicFrame* frame) { |
| if (!HasRoomForStreamFrame(id, offset, data_size)) { |
| return false; |
| } |
| CreateStreamFrame(id, data_size, offset, fin, frame); |
| // Explicitly disallow multi-packet CHLOs. |
| if (GetQuicFlag(FLAGS_quic_enforce_single_packet_chlo) && |
| StreamFrameIsClientHello(frame->stream_frame) && |
| frame->stream_frame.data_length < data_size) { |
| const std::string error_details = |
| "Client hello won't fit in a single packet."; |
| QUIC_BUG << error_details << " Constructed stream frame length: " |
| << frame->stream_frame.data_length |
| << " CHLO length: " << data_size; |
| delegate_->OnUnrecoverableError(QUIC_CRYPTO_CHLO_TOO_LARGE, error_details); |
| return false; |
| } |
| if (!AddFrame(*frame, /*save_retransmittable_frames=*/true, |
| transmission_type)) { |
| // Fails if we try to write unencrypted stream data. |
| return false; |
| } |
| if (needs_full_padding) { |
| needs_full_padding_ = true; |
| } |
| |
| return true; |
| } |
| |
| bool QuicPacketCreator::HasRoomForStreamFrame(QuicStreamId id, |
| QuicStreamOffset offset, |
| size_t data_size) { |
| return BytesFree() > |
| QuicFramer::GetMinStreamFrameSize(framer_->transport_version(), id, |
| offset, true, data_size); |
| } |
| |
| bool QuicPacketCreator::HasRoomForMessageFrame(QuicByteCount length) { |
| return BytesFree() >= QuicFramer::GetMessageFrameSize( |
| framer_->transport_version(), true, length); |
| } |
| |
| // TODO(fkastenholz): this method should not use constant values for |
| // the last-frame-in-packet and data-length parameters to |
| // GetMinStreamFrameSize. Proper values should be plumbed in from |
| // higher up. This was left this way for now for a few reasons. First, |
| // higher up calls to StreamFramePacketOverhead() do not always know |
| // this information, leading to a cascade of changes and B) the |
| // higher-up software does not always loop, calling |
| // StreamFramePacketOverhead() once for every packet -- eg there is |
| // a test in quic_connection_test that calls it once and assumes that |
| // the value is the same for all packets. |
| |
| // static |
| size_t QuicPacketCreator::StreamFramePacketOverhead( |
| QuicTransportVersion version, |
| QuicConnectionIdLength destination_connection_id_length, |
| QuicConnectionIdLength source_connection_id_length, |
| bool include_version, |
| bool include_diversification_nonce, |
| QuicPacketNumberLength packet_number_length, |
| QuicVariableLengthIntegerLength retry_token_length_length, |
| QuicVariableLengthIntegerLength length_length, |
| QuicStreamOffset offset) { |
| return GetPacketHeaderSize(version, destination_connection_id_length, |
| source_connection_id_length, include_version, |
| include_diversification_nonce, |
| packet_number_length, retry_token_length_length, 0, |
| length_length) + |
| |
| // Assumes this is a packet with a single stream frame in it. Since |
| // last_frame_in_packet is set true, the size of the length field is |
| // not included in the calculation. This is OK because in other places |
| // in the code, the logic adds back 2 (the size of the Google QUIC |
| // length) when a frame is not the last frame of the packet. This is |
| // also acceptable for IETF Quic; even though the length field could be |
| // 8 bytes long, in practice it will not be longer than 2 bytes (enough |
| // to encode 16K). A length that would be encoded in 2 bytes (0xfff) |
| // is passed just for cleanliness. |
| // |
| // TODO(fkastenholz): This is very hacky and feels brittle. Ideally we |
| // would calculate the correct lengths at the correct time, based on |
| // the state at that time/place. |
| QuicFramer::GetMinStreamFrameSize(version, 1u, offset, true, |
| kMaxOutgoingPacketSize); |
| } |
| |
| void QuicPacketCreator::CreateStreamFrame(QuicStreamId id, |
| size_t data_size, |
| QuicStreamOffset offset, |
| bool fin, |
| QuicFrame* frame) { |
| DCHECK_GT( |
| max_packet_length_, |
| StreamFramePacketOverhead( |
| framer_->transport_version(), GetDestinationConnectionIdLength(), |
| GetSourceConnectionIdLength(), kIncludeVersion, |
| IncludeNonceInPublicHeader(), PACKET_6BYTE_PACKET_NUMBER, |
| GetRetryTokenLengthLength(), GetLengthLength(), offset)); |
| |
| QUIC_BUG_IF(!HasRoomForStreamFrame(id, offset, data_size)) |
| << "No room for Stream frame, BytesFree: " << BytesFree() |
| << " MinStreamFrameSize: " |
| << QuicFramer::GetMinStreamFrameSize(framer_->transport_version(), id, |
| offset, true, data_size); |
| |
| QUIC_BUG_IF(data_size == 0 && !fin) |
| << "Creating a stream frame for stream ID:" << id |
| << " with no data or fin."; |
| size_t min_frame_size = QuicFramer::GetMinStreamFrameSize( |
| framer_->transport_version(), id, offset, |
| /* last_frame_in_packet= */ true, data_size); |
| size_t bytes_consumed = |
| std::min<size_t>(BytesFree() - min_frame_size, data_size); |
| |
| bool set_fin = fin && bytes_consumed == data_size; // Last frame. |
| *frame = QuicFrame(QuicStreamFrame(id, set_fin, offset, bytes_consumed)); |
| } |
| |
| bool QuicPacketCreator::CreateCryptoFrame(EncryptionLevel level, |
| size_t write_length, |
| QuicStreamOffset offset, |
| QuicFrame* frame) { |
| size_t min_frame_size = |
| QuicFramer::GetMinCryptoFrameSize(write_length, offset); |
| if (BytesFree() <= min_frame_size) { |
| return false; |
| } |
| size_t max_write_length = BytesFree() - min_frame_size; |
| size_t bytes_consumed = std::min<size_t>(max_write_length, write_length); |
| *frame = QuicFrame(new QuicCryptoFrame(level, offset, bytes_consumed)); |
| return true; |
| } |
| |
| void QuicPacketCreator::ReserializeAllFrames( |
| const QuicPendingRetransmission& retransmission, |
| char* buffer, |
| size_t buffer_len) { |
| DCHECK(queued_frames_.empty()); |
| DCHECK_EQ(0, packet_.num_padding_bytes); |
| QUIC_BUG_IF(retransmission.retransmittable_frames.empty()) |
| << "Attempt to serialize empty packet"; |
| const EncryptionLevel default_encryption_level = packet_.encryption_level; |
| |
| // Temporarily set the packet number length and change the encryption level. |
| packet_.packet_number_length = retransmission.packet_number_length; |
| if (retransmission.num_padding_bytes == -1) { |
| // Only retransmit padding when original packet needs full padding. Padding |
| // from pending_padding_bytes_ are not retransmitted. |
| needs_full_padding_ = true; |
| } |
| // Only preserve the original encryption level if it's a handshake packet or |
| // if we haven't gone forward secure. |
| if (retransmission.has_crypto_handshake || |
| packet_.encryption_level != ENCRYPTION_FORWARD_SECURE) { |
| packet_.encryption_level = retransmission.encryption_level; |
| } |
| |
| // Serialize the packet and restore packet number length state. |
| for (const QuicFrame& frame : retransmission.retransmittable_frames) { |
| bool success = AddFrame(frame, false, retransmission.transmission_type); |
| QUIC_BUG_IF(!success) << " Failed to add frame of type:" << frame.type |
| << " num_frames:" |
| << retransmission.retransmittable_frames.size() |
| << " retransmission.packet_number_length:" |
| << retransmission.packet_number_length |
| << " packet_.packet_number_length:" |
| << packet_.packet_number_length; |
| } |
| packet_.transmission_type = retransmission.transmission_type; |
| SerializePacket(buffer, buffer_len); |
| packet_.original_packet_number = retransmission.packet_number; |
| OnSerializedPacket(); |
| // Restore old values. |
| packet_.encryption_level = default_encryption_level; |
| } |
| |
| void QuicPacketCreator::Flush() { |
| if (!HasPendingFrames() && pending_padding_bytes_ == 0) { |
| return; |
| } |
| |
| QUIC_CACHELINE_ALIGNED char stack_buffer[kMaxOutgoingPacketSize]; |
| char* serialized_packet_buffer = delegate_->GetPacketBuffer(); |
| if (serialized_packet_buffer == nullptr) { |
| serialized_packet_buffer = stack_buffer; |
| } |
| |
| SerializePacket(serialized_packet_buffer, kMaxOutgoingPacketSize); |
| OnSerializedPacket(); |
| } |
| |
| void QuicPacketCreator::OnSerializedPacket() { |
| if (packet_.encrypted_buffer == nullptr) { |
| const std::string error_details = "Failed to SerializePacket."; |
| QUIC_BUG << error_details; |
| delegate_->OnUnrecoverableError(QUIC_FAILED_TO_SERIALIZE_PACKET, |
| error_details); |
| return; |
| } |
| |
| SerializedPacket packet(std::move(packet_)); |
| ClearPacket(); |
| delegate_->OnSerializedPacket(&packet); |
| } |
| |
| void QuicPacketCreator::ClearPacket() { |
| packet_.has_ack = false; |
| packet_.has_stop_waiting = false; |
| packet_.has_crypto_handshake = NOT_HANDSHAKE; |
| packet_.num_padding_bytes = 0; |
| packet_.original_packet_number.Clear(); |
| packet_.transmission_type = NOT_RETRANSMISSION; |
| packet_.encrypted_buffer = nullptr; |
| packet_.encrypted_length = 0; |
| DCHECK(packet_.retransmittable_frames.empty()); |
| packet_.largest_acked.Clear(); |
| needs_full_padding_ = false; |
| } |
| |
| void QuicPacketCreator::CreateAndSerializeStreamFrame( |
| QuicStreamId id, |
| size_t write_length, |
| QuicStreamOffset iov_offset, |
| QuicStreamOffset stream_offset, |
| bool fin, |
| TransmissionType transmission_type, |
| size_t* num_bytes_consumed) { |
| DCHECK(queued_frames_.empty()); |
| // Write out the packet header |
| QuicPacketHeader header; |
| FillPacketHeader(&header); |
| |
| QUIC_CACHELINE_ALIGNED char stack_buffer[kMaxOutgoingPacketSize]; |
| char* encrypted_buffer = delegate_->GetPacketBuffer(); |
| if (encrypted_buffer == nullptr) { |
| encrypted_buffer = stack_buffer; |
| } |
| |
| QuicDataWriter writer(kMaxOutgoingPacketSize, encrypted_buffer); |
| size_t length_field_offset = 0; |
| if (!framer_->AppendPacketHeader(header, &writer, &length_field_offset)) { |
| QUIC_BUG << "AppendPacketHeader failed"; |
| return; |
| } |
| |
| // Create a Stream frame with the remaining space. |
| QUIC_BUG_IF(iov_offset == write_length && !fin) |
| << "Creating a stream frame with no data or fin."; |
| const size_t remaining_data_size = write_length - iov_offset; |
| size_t min_frame_size = QuicFramer::GetMinStreamFrameSize( |
| framer_->transport_version(), id, stream_offset, |
| /* last_frame_in_packet= */ true, remaining_data_size); |
| size_t available_size = |
| max_plaintext_size_ - writer.length() - min_frame_size; |
| size_t bytes_consumed = std::min<size_t>(available_size, remaining_data_size); |
| size_t plaintext_bytes_written = min_frame_size + bytes_consumed; |
| bool needs_padding = false; |
| if (plaintext_bytes_written < MinPlaintextPacketSize(framer_->version())) { |
| needs_padding = true; |
| // Recalculate sizes with the stream frame not being marked as the last |
| // frame in the packet. |
| min_frame_size = QuicFramer::GetMinStreamFrameSize( |
| framer_->transport_version(), id, stream_offset, |
| /* last_frame_in_packet= */ false, remaining_data_size); |
| available_size = max_plaintext_size_ - writer.length() - min_frame_size; |
| bytes_consumed = std::min<size_t>(available_size, remaining_data_size); |
| plaintext_bytes_written = min_frame_size + bytes_consumed; |
| } |
| |
| const bool set_fin = fin && (bytes_consumed == remaining_data_size); |
| QuicStreamFrame frame(id, set_fin, stream_offset, bytes_consumed); |
| if (debug_delegate_ != nullptr) { |
| debug_delegate_->OnFrameAddedToPacket(QuicFrame(frame)); |
| } |
| QUIC_DVLOG(1) << ENDPOINT << "Adding frame: " << frame; |
| |
| QUIC_DVLOG(2) << ENDPOINT << "Serializing stream packet " << header << frame; |
| |
| // TODO(ianswett): AppendTypeByte and AppendStreamFrame could be optimized |
| // into one method that takes a QuicStreamFrame, if warranted. |
| bool omit_frame_length = !needs_padding; |
| if (!framer_->AppendTypeByte(QuicFrame(frame), omit_frame_length, &writer)) { |
| QUIC_BUG << "AppendTypeByte failed"; |
| return; |
| } |
| if (!framer_->AppendStreamFrame(frame, omit_frame_length, &writer)) { |
| QUIC_BUG << "AppendStreamFrame failed"; |
| return; |
| } |
| if (needs_padding && |
| plaintext_bytes_written < MinPlaintextPacketSize(framer_->version()) && |
| !writer.WritePaddingBytes(MinPlaintextPacketSize(framer_->version()) - |
| plaintext_bytes_written)) { |
| QUIC_BUG << "Unable to add padding bytes"; |
| return; |
| } |
| |
| if (!framer_->WriteIetfLongHeaderLength(header, &writer, length_field_offset, |
| packet_.encryption_level)) { |
| return; |
| } |
| |
| if (can_set_transmission_type()) { |
| packet_.transmission_type = transmission_type; |
| } |
| |
| size_t encrypted_length = framer_->EncryptInPlace( |
| packet_.encryption_level, packet_.packet_number, |
| GetStartOfEncryptedData(framer_->transport_version(), header), |
| writer.length(), kMaxOutgoingPacketSize, encrypted_buffer); |
| if (encrypted_length == 0) { |
| QUIC_BUG << "Failed to encrypt packet number " << header.packet_number; |
| return; |
| } |
| // TODO(ianswett): Optimize the storage so RetransmitableFrames can be |
| // unioned with a QuicStreamFrame and a UniqueStreamBuffer. |
| *num_bytes_consumed = bytes_consumed; |
| packet_size_ = 0; |
| packet_.encrypted_buffer = encrypted_buffer; |
| packet_.encrypted_length = encrypted_length; |
| packet_.retransmittable_frames.push_back(QuicFrame(frame)); |
| OnSerializedPacket(); |
| } |
| |
| bool QuicPacketCreator::HasPendingFrames() const { |
| return !queued_frames_.empty(); |
| } |
| |
| bool QuicPacketCreator::HasPendingRetransmittableFrames() const { |
| return !packet_.retransmittable_frames.empty(); |
| } |
| |
| bool QuicPacketCreator::HasPendingStreamFramesOfStream(QuicStreamId id) const { |
| for (const auto& frame : packet_.retransmittable_frames) { |
| if (frame.type == STREAM_FRAME && frame.stream_frame.stream_id == id) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| size_t QuicPacketCreator::ExpansionOnNewFrame() const { |
| // If the last frame in the packet is a message frame, then it will expand to |
| // include the varint message length when a new frame is added. |
| const bool has_trailing_message_frame = |
| !queued_frames_.empty() && queued_frames_.back().type == MESSAGE_FRAME; |
| if (has_trailing_message_frame) { |
| return QuicDataWriter::GetVarInt62Len( |
| queued_frames_.back().message_frame->message_length); |
| } |
| // If the last frame in the packet is a stream frame, then it will expand to |
| // include the stream_length field when a new frame is added. |
| const bool has_trailing_stream_frame = |
| !queued_frames_.empty() && queued_frames_.back().type == STREAM_FRAME; |
| if (!has_trailing_stream_frame) { |
| return 0; |
| } |
| if (VersionHasIetfQuicFrames(framer_->transport_version())) { |
| return QuicDataWriter::GetVarInt62Len( |
| queued_frames_.back().stream_frame.data_length); |
| } |
| return kQuicStreamPayloadLengthSize; |
| } |
| |
| size_t QuicPacketCreator::BytesFree() { |
| DCHECK_GE(max_plaintext_size_, PacketSize()); |
| return max_plaintext_size_ - |
| std::min(max_plaintext_size_, PacketSize() + ExpansionOnNewFrame()); |
| } |
| |
| size_t QuicPacketCreator::PacketSize() { |
| if (!queued_frames_.empty()) { |
| return packet_size_; |
| } |
| packet_size_ = PacketHeaderSize(); |
| return packet_size_; |
| } |
| |
| bool QuicPacketCreator::AddSavedFrame(const QuicFrame& frame, |
| TransmissionType transmission_type) { |
| return AddFrame(frame, /*save_retransmittable_frames=*/true, |
| transmission_type); |
| } |
| |
| bool QuicPacketCreator::AddPaddedSavedFrame( |
| const QuicFrame& frame, |
| TransmissionType transmission_type) { |
| if (AddFrame(frame, /*save_retransmittable_frames=*/true, |
| transmission_type)) { |
| needs_full_padding_ = true; |
| return true; |
| } |
| return false; |
| } |
| |
| void QuicPacketCreator::SerializePacket(char* encrypted_buffer, |
| size_t encrypted_buffer_len) { |
| DCHECK_LT(0u, encrypted_buffer_len); |
| QUIC_BUG_IF(queued_frames_.empty() && pending_padding_bytes_ == 0) |
| << "Attempt to serialize empty packet"; |
| QuicPacketHeader header; |
| // FillPacketHeader increments packet_number_. |
| FillPacketHeader(&header); |
| |
| MaybeAddPadding(); |
| |
| QUIC_DVLOG(2) << ENDPOINT << "Serializing packet " << header |
| << QuicFramesToString(queued_frames_); |
| |
| DCHECK_GE(max_plaintext_size_, packet_size_); |
| // Use the packet_size_ instead of the buffer size to ensure smaller |
| // packet sizes are properly used. |
| size_t length = |
| framer_->BuildDataPacket(header, queued_frames_, encrypted_buffer, |
| packet_size_, packet_.encryption_level); |
| if (length == 0) { |
| QUIC_BUG << "Failed to serialize " << queued_frames_.size() << " frames."; |
| return; |
| } |
| |
| // ACK Frames will be truncated due to length only if they're the only frame |
| // in the packet, and if packet_size_ was set to max_plaintext_size_. If |
| // truncation due to length occurred, then GetSerializedFrameLength will have |
| // returned all bytes free. |
| bool possibly_truncated_by_length = packet_size_ == max_plaintext_size_ && |
| queued_frames_.size() == 1 && |
| queued_frames_.back().type == ACK_FRAME; |
| // Because of possible truncation, we can't be confident that our |
| // packet size calculation worked correctly. |
| if (!possibly_truncated_by_length) { |
| DCHECK_EQ(packet_size_, length); |
| } |
| const size_t encrypted_length = framer_->EncryptInPlace( |
| packet_.encryption_level, packet_.packet_number, |
| GetStartOfEncryptedData(framer_->transport_version(), header), length, |
| encrypted_buffer_len, encrypted_buffer); |
| if (encrypted_length == 0) { |
| QUIC_BUG << "Failed to encrypt packet number " << packet_.packet_number; |
| return; |
| } |
| |
| packet_size_ = 0; |
| queued_frames_.clear(); |
| packet_.encrypted_buffer = encrypted_buffer; |
| packet_.encrypted_length = encrypted_length; |
| } |
| |
| std::unique_ptr<QuicEncryptedPacket> |
| QuicPacketCreator::SerializeVersionNegotiationPacket( |
| bool ietf_quic, |
| bool use_length_prefix, |
| const ParsedQuicVersionVector& supported_versions) { |
| DCHECK_EQ(Perspective::IS_SERVER, framer_->perspective()); |
| std::unique_ptr<QuicEncryptedPacket> encrypted = |
| QuicFramer::BuildVersionNegotiationPacket( |
| server_connection_id_, client_connection_id_, ietf_quic, |
| use_length_prefix, supported_versions); |
| DCHECK(encrypted); |
| DCHECK_GE(max_packet_length_, encrypted->length()); |
| return encrypted; |
| } |
| |
| OwningSerializedPacketPointer |
| QuicPacketCreator::SerializeConnectivityProbingPacket() { |
| QUIC_BUG_IF(VersionHasIetfQuicFrames(framer_->transport_version())) |
| << "Must not be version 99 to serialize padded ping connectivity probe"; |
| QuicPacketHeader header; |
| // FillPacketHeader increments packet_number_. |
| FillPacketHeader(&header); |
| |
| QUIC_DVLOG(2) << ENDPOINT << "Serializing connectivity probing packet " |
| << header; |
| |
| std::unique_ptr<char[]> buffer(new char[kMaxOutgoingPacketSize]); |
| size_t length = framer_->BuildConnectivityProbingPacket( |
| header, buffer.get(), max_plaintext_size_, packet_.encryption_level); |
| DCHECK(length); |
| |
| const size_t encrypted_length = framer_->EncryptInPlace( |
| packet_.encryption_level, packet_.packet_number, |
| GetStartOfEncryptedData(framer_->transport_version(), header), length, |
| kMaxOutgoingPacketSize, buffer.get()); |
| DCHECK(encrypted_length); |
| |
| OwningSerializedPacketPointer serialize_packet(new SerializedPacket( |
| header.packet_number, header.packet_number_length, buffer.release(), |
| encrypted_length, /*has_ack=*/false, /*has_stop_waiting=*/false)); |
| |
| serialize_packet->encryption_level = packet_.encryption_level; |
| serialize_packet->transmission_type = NOT_RETRANSMISSION; |
| |
| return serialize_packet; |
| } |
| |
| OwningSerializedPacketPointer |
| QuicPacketCreator::SerializePathChallengeConnectivityProbingPacket( |
| QuicPathFrameBuffer* payload) { |
| QUIC_BUG_IF(!VersionHasIetfQuicFrames(framer_->transport_version())) |
| << "Must be version 99 to serialize path challenge connectivity probe, " |
| "is version " |
| << framer_->transport_version(); |
| QuicPacketHeader header; |
| // FillPacketHeader increments packet_number_. |
| FillPacketHeader(&header); |
| |
| QUIC_DVLOG(2) << ENDPOINT << "Serializing path challenge packet " << header; |
| |
| std::unique_ptr<char[]> buffer(new char[kMaxOutgoingPacketSize]); |
| size_t length = framer_->BuildPaddedPathChallengePacket( |
| header, buffer.get(), max_plaintext_size_, payload, random_, |
| packet_.encryption_level); |
| DCHECK(length); |
| |
| const size_t encrypted_length = framer_->EncryptInPlace( |
| packet_.encryption_level, packet_.packet_number, |
| GetStartOfEncryptedData(framer_->transport_version(), header), length, |
| kMaxOutgoingPacketSize, buffer.get()); |
| DCHECK(encrypted_length); |
| |
| OwningSerializedPacketPointer serialize_packet(new SerializedPacket( |
| header.packet_number, header.packet_number_length, buffer.release(), |
| encrypted_length, /*has_ack=*/false, /*has_stop_waiting=*/false)); |
| |
| serialize_packet->encryption_level = packet_.encryption_level; |
| serialize_packet->transmission_type = NOT_RETRANSMISSION; |
| |
| return serialize_packet; |
| } |
| |
| OwningSerializedPacketPointer |
| QuicPacketCreator::SerializePathResponseConnectivityProbingPacket( |
| const QuicDeque<QuicPathFrameBuffer>& payloads, |
| const bool is_padded) { |
| QUIC_BUG_IF(!VersionHasIetfQuicFrames(framer_->transport_version())) |
| << "Must be version 99 to serialize path response connectivity probe, is " |
| "version " |
| << framer_->transport_version(); |
| QuicPacketHeader header; |
| // FillPacketHeader increments packet_number_. |
| FillPacketHeader(&header); |
| |
| QUIC_DVLOG(2) << ENDPOINT << "Serializing path response packet " << header; |
| |
| std::unique_ptr<char[]> buffer(new char[kMaxOutgoingPacketSize]); |
| size_t length = framer_->BuildPathResponsePacket( |
| header, buffer.get(), max_plaintext_size_, payloads, is_padded, |
| packet_.encryption_level); |
| DCHECK(length); |
| |
| const size_t encrypted_length = framer_->EncryptInPlace( |
| packet_.encryption_level, packet_.packet_number, |
| GetStartOfEncryptedData(framer_->transport_version(), header), length, |
| kMaxOutgoingPacketSize, buffer.get()); |
| DCHECK(encrypted_length); |
| |
| OwningSerializedPacketPointer serialize_packet(new SerializedPacket( |
| header.packet_number, header.packet_number_length, buffer.release(), |
| encrypted_length, /*has_ack=*/false, /*has_stop_waiting=*/false)); |
| |
| serialize_packet->encryption_level = packet_.encryption_level; |
| serialize_packet->transmission_type = NOT_RETRANSMISSION; |
| |
| return serialize_packet; |
| } |
| |
| // TODO(b/74062209): Make this a public method of framer? |
| SerializedPacket QuicPacketCreator::NoPacket() { |
| return SerializedPacket(QuicPacketNumber(), PACKET_1BYTE_PACKET_NUMBER, |
| nullptr, 0, false, false); |
| } |
| |
| QuicConnectionId QuicPacketCreator::GetDestinationConnectionId() const { |
| if (framer_->perspective() == Perspective::IS_SERVER) { |
| return client_connection_id_; |
| } |
| return server_connection_id_; |
| } |
| |
| QuicConnectionId QuicPacketCreator::GetSourceConnectionId() const { |
| if (framer_->perspective() == Perspective::IS_CLIENT) { |
| return client_connection_id_; |
| } |
| return server_connection_id_; |
| } |
| |
| QuicConnectionIdIncluded QuicPacketCreator::GetDestinationConnectionIdIncluded() |
| const { |
| // In versions that do not support client connection IDs, the destination |
| // connection ID is only sent from client to server. |
| return (framer_->perspective() == Perspective::IS_CLIENT || |
| framer_->version().SupportsClientConnectionIds()) |
| ? CONNECTION_ID_PRESENT |
| : CONNECTION_ID_ABSENT; |
| } |
| |
| QuicConnectionIdIncluded QuicPacketCreator::GetSourceConnectionIdIncluded() |
| const { |
| // Long header packets sent by server include source connection ID. |
| // Ones sent by the client only include source connection ID if the version |
| // supports client connection IDs. |
| if (HasIetfLongHeader() && |
| (framer_->perspective() == Perspective::IS_SERVER || |
| framer_->version().SupportsClientConnectionIds())) { |
| return CONNECTION_ID_PRESENT; |
| } |
| if (framer_->perspective() == Perspective::IS_SERVER) { |
| return server_connection_id_included_; |
| } |
| return CONNECTION_ID_ABSENT; |
| } |
| |
| QuicConnectionIdLength QuicPacketCreator::GetDestinationConnectionIdLength() |
| const { |
| DCHECK(QuicUtils::IsConnectionIdValidForVersion(server_connection_id_, |
| transport_version())); |
| return GetDestinationConnectionIdIncluded() == CONNECTION_ID_PRESENT |
| ? static_cast<QuicConnectionIdLength>( |
| GetDestinationConnectionId().length()) |
| : PACKET_0BYTE_CONNECTION_ID; |
| } |
| |
| QuicConnectionIdLength QuicPacketCreator::GetSourceConnectionIdLength() const { |
| DCHECK(QuicUtils::IsConnectionIdValidForVersion(server_connection_id_, |
| transport_version())); |
| return GetSourceConnectionIdIncluded() == CONNECTION_ID_PRESENT |
| ? static_cast<QuicConnectionIdLength>( |
| GetSourceConnectionId().length()) |
| : PACKET_0BYTE_CONNECTION_ID; |
| } |
| |
| QuicPacketNumberLength QuicPacketCreator::GetPacketNumberLength() const { |
| if (HasIetfLongHeader() && |
| !framer_->version().SendsVariableLengthPacketNumberInLongHeader()) { |
| return PACKET_4BYTE_PACKET_NUMBER; |
| } |
| return packet_.packet_number_length; |
| } |
| |
| size_t QuicPacketCreator::PacketHeaderSize() const { |
| return GetPacketHeaderSize( |
| framer_->transport_version(), GetDestinationConnectionIdLength(), |
| GetSourceConnectionIdLength(), IncludeVersionInHeader(), |
| IncludeNonceInPublicHeader(), GetPacketNumberLength(), |
| GetRetryTokenLengthLength(), GetRetryToken().length(), GetLengthLength()); |
| } |
| |
| QuicVariableLengthIntegerLength QuicPacketCreator::GetRetryTokenLengthLength() |
| const { |
| if (QuicVersionHasLongHeaderLengths(framer_->transport_version()) && |
| HasIetfLongHeader() && |
| EncryptionlevelToLongHeaderType(packet_.encryption_level) == INITIAL) { |
| return QuicDataWriter::GetVarInt62Len(GetRetryToken().length()); |
| } |
| return VARIABLE_LENGTH_INTEGER_LENGTH_0; |
| } |
| |
| QuicStringPiece QuicPacketCreator::GetRetryToken() const { |
| if (QuicVersionHasLongHeaderLengths(framer_->transport_version()) && |
| HasIetfLongHeader() && |
| EncryptionlevelToLongHeaderType(packet_.encryption_level) == INITIAL) { |
| return retry_token_; |
| } |
| return QuicStringPiece(); |
| } |
| |
| void QuicPacketCreator::SetRetryToken(QuicStringPiece retry_token) { |
| retry_token_ = std::string(retry_token); |
| } |
| |
| QuicVariableLengthIntegerLength QuicPacketCreator::GetLengthLength() const { |
| if (QuicVersionHasLongHeaderLengths(framer_->transport_version()) && |
| HasIetfLongHeader()) { |
| QuicLongHeaderType long_header_type = |
| EncryptionlevelToLongHeaderType(packet_.encryption_level); |
| if (long_header_type == INITIAL || long_header_type == ZERO_RTT_PROTECTED || |
| long_header_type == HANDSHAKE) { |
| return VARIABLE_LENGTH_INTEGER_LENGTH_2; |
| } |
| } |
| return VARIABLE_LENGTH_INTEGER_LENGTH_0; |
| } |
| |
| void QuicPacketCreator::FillPacketHeader(QuicPacketHeader* header) { |
| header->destination_connection_id = GetDestinationConnectionId(); |
| header->destination_connection_id_included = |
| GetDestinationConnectionIdIncluded(); |
| header->source_connection_id = GetSourceConnectionId(); |
| header->source_connection_id_included = GetSourceConnectionIdIncluded(); |
| header->reset_flag = false; |
| header->version_flag = IncludeVersionInHeader(); |
| if (IncludeNonceInPublicHeader()) { |
| DCHECK_EQ(Perspective::IS_SERVER, framer_->perspective()); |
| header->nonce = &diversification_nonce_; |
| } else { |
| header->nonce = nullptr; |
| } |
| packet_.packet_number = NextSendingPacketNumber(); |
| header->packet_number = packet_.packet_number; |
| header->packet_number_length = GetPacketNumberLength(); |
| header->retry_token_length_length = GetRetryTokenLengthLength(); |
| header->retry_token = GetRetryToken(); |
| header->length_length = GetLengthLength(); |
| header->remaining_packet_length = 0; |
| if (!HasIetfLongHeader()) { |
| return; |
| } |
| header->long_packet_type = |
| EncryptionlevelToLongHeaderType(packet_.encryption_level); |
| } |
| |
| bool QuicPacketCreator::AddFrame(const QuicFrame& frame, |
| bool save_retransmittable_frames, |
| TransmissionType transmission_type) { |
| QUIC_DVLOG(1) << ENDPOINT << "Adding frame with transmission type " |
| << transmission_type << ": " << frame; |
| if (frame.type == STREAM_FRAME && |
| !QuicUtils::IsCryptoStreamId(framer_->transport_version(), |
| frame.stream_frame.stream_id) && |
| (packet_.encryption_level == ENCRYPTION_INITIAL || |
| packet_.encryption_level == ENCRYPTION_HANDSHAKE)) { |
| const std::string error_details = QuicStrCat( |
| "Cannot send stream data with level: ", |
| QuicUtils::EncryptionLevelToString(packet_.encryption_level)); |
| QUIC_BUG << error_details; |
| delegate_->OnUnrecoverableError( |
| QUIC_ATTEMPT_TO_SEND_UNENCRYPTED_STREAM_DATA, error_details); |
| return false; |
| } |
| size_t frame_len = framer_->GetSerializedFrameLength( |
| frame, BytesFree(), queued_frames_.empty(), |
| /* last_frame_in_packet= */ true, GetPacketNumberLength()); |
| if (frame_len == 0) { |
| // Current open packet is full. |
| Flush(); |
| return false; |
| } |
| DCHECK_LT(0u, packet_size_); |
| |
| packet_size_ += ExpansionOnNewFrame() + frame_len; |
| |
| if (save_retransmittable_frames && |
| QuicUtils::IsRetransmittableFrame(frame.type)) { |
| packet_.retransmittable_frames.push_back(frame); |
| queued_frames_.push_back(frame); |
| if (QuicUtils::IsHandshakeFrame(frame, framer_->transport_version())) { |
| packet_.has_crypto_handshake = IS_HANDSHAKE; |
| } |
| } else { |
| queued_frames_.push_back(frame); |
| } |
| |
| if (frame.type == ACK_FRAME) { |
| packet_.has_ack = true; |
| packet_.largest_acked = LargestAcked(*frame.ack_frame); |
| } |
| if (frame.type == STOP_WAITING_FRAME) { |
| packet_.has_stop_waiting = true; |
| } |
| if (debug_delegate_ != nullptr) { |
| debug_delegate_->OnFrameAddedToPacket(frame); |
| } |
| |
| // Packet transmission type is determined by the last added retransmittable |
| // frame. |
| if (can_set_transmission_type() && |
| QuicUtils::IsRetransmittableFrame(frame.type)) { |
| packet_.transmission_type = transmission_type; |
| } |
| return true; |
| } |
| |
| void QuicPacketCreator::MaybeAddPadding() { |
| // The current packet should have no padding bytes because padding is only |
| // added when this method is called just before the packet is serialized. |
| DCHECK_EQ(0, packet_.num_padding_bytes); |
| if (BytesFree() == 0) { |
| // Don't pad full packets. |
| return; |
| } |
| |
| if (packet_.transmission_type == PROBING_RETRANSMISSION) { |
| needs_full_padding_ = true; |
| } |
| |
| // Header protection requires a minimum plaintext packet size. |
| size_t extra_padding_bytes = 0; |
| if (framer_->version().HasHeaderProtection()) { |
| size_t frame_bytes = PacketSize() - PacketHeaderSize(); |
| |
| if (frame_bytes + pending_padding_bytes_ < |
| MinPlaintextPacketSize(framer_->version()) && |
| !needs_full_padding_) { |
| extra_padding_bytes = |
| MinPlaintextPacketSize(framer_->version()) - frame_bytes; |
| } |
| } |
| |
| if (!needs_full_padding_ && pending_padding_bytes_ == 0 && |
| extra_padding_bytes == 0) { |
| // Do not need padding. |
| return; |
| } |
| |
| int padding_bytes = -1; |
| if (needs_full_padding_) { |
| // Full padding does not consume pending padding bytes. |
| packet_.num_padding_bytes = -1; |
| } else { |
| packet_.num_padding_bytes = |
| std::min<int16_t>(pending_padding_bytes_, BytesFree()); |
| pending_padding_bytes_ -= packet_.num_padding_bytes; |
| padding_bytes = |
| std::max<int16_t>(packet_.num_padding_bytes, extra_padding_bytes); |
| } |
| |
| bool success = AddFrame(QuicFrame(QuicPaddingFrame(padding_bytes)), false, |
| packet_.transmission_type); |
| DCHECK(success); |
| } |
| |
| bool QuicPacketCreator::IncludeNonceInPublicHeader() const { |
| return have_diversification_nonce_ && |
| packet_.encryption_level == ENCRYPTION_ZERO_RTT; |
| } |
| |
| bool QuicPacketCreator::IncludeVersionInHeader() const { |
| if (VersionHasIetfInvariantHeader(framer_->transport_version())) { |
| return packet_.encryption_level < ENCRYPTION_FORWARD_SECURE; |
| } |
| return send_version_in_packet_; |
| } |
| |
| void QuicPacketCreator::AddPendingPadding(QuicByteCount size) { |
| pending_padding_bytes_ += size; |
| } |
| |
| bool QuicPacketCreator::StreamFrameIsClientHello( |
| const QuicStreamFrame& frame) const { |
| if (framer_->perspective() == Perspective::IS_SERVER || |
| !QuicUtils::IsCryptoStreamId(framer_->transport_version(), |
| frame.stream_id)) { |
| return false; |
| } |
| // The ClientHello is always sent with INITIAL encryption. |
| return packet_.encryption_level == ENCRYPTION_INITIAL; |
| } |
| |
| void QuicPacketCreator::SetServerConnectionIdIncluded( |
| QuicConnectionIdIncluded server_connection_id_included) { |
| DCHECK(server_connection_id_included == CONNECTION_ID_PRESENT || |
| server_connection_id_included == CONNECTION_ID_ABSENT); |
| DCHECK(framer_->perspective() == Perspective::IS_SERVER || |
| server_connection_id_included != CONNECTION_ID_ABSENT); |
| server_connection_id_included_ = server_connection_id_included; |
| } |
| |
| void QuicPacketCreator::SetServerConnectionId( |
| QuicConnectionId server_connection_id) { |
| server_connection_id_ = server_connection_id; |
| } |
| |
| void QuicPacketCreator::SetClientConnectionId( |
| QuicConnectionId client_connection_id) { |
| DCHECK(client_connection_id.IsEmpty() || |
| framer_->version().SupportsClientConnectionIds()); |
| client_connection_id_ = client_connection_id; |
| } |
| |
| void QuicPacketCreator::SetTransmissionType(TransmissionType type) { |
| DCHECK(can_set_transmission_type_); |
| |
| if (!can_set_transmission_type()) { |
| QUIC_DVLOG_IF(1, type != packet_.transmission_type) |
| << ENDPOINT << "Setting Transmission type to " |
| << QuicUtils::TransmissionTypeToString(type); |
| |
| packet_.transmission_type = type; |
| } |
| } |
| |
| QuicPacketLength QuicPacketCreator::GetCurrentLargestMessagePayload() const { |
| if (!VersionSupportsMessageFrames(framer_->transport_version())) { |
| return 0; |
| } |
| const size_t packet_header_size = GetPacketHeaderSize( |
| framer_->transport_version(), GetDestinationConnectionIdLength(), |
| GetSourceConnectionIdLength(), IncludeVersionInHeader(), |
| IncludeNonceInPublicHeader(), GetPacketNumberLength(), |
| // No Retry token on packets containing application data. |
| VARIABLE_LENGTH_INTEGER_LENGTH_0, 0, GetLengthLength()); |
| // This is the largest possible message payload when the length field is |
| // omitted. |
| return max_plaintext_size_ - |
| std::min(max_plaintext_size_, packet_header_size + kQuicFrameTypeSize); |
| } |
| |
| QuicPacketLength QuicPacketCreator::GetGuaranteedLargestMessagePayload() const { |
| if (!VersionSupportsMessageFrames(framer_->transport_version())) { |
| return 0; |
| } |
| // QUIC Crypto server packets may include a diversification nonce. |
| const bool may_include_nonce = |
| framer_->version().handshake_protocol == PROTOCOL_QUIC_CRYPTO && |
| framer_->perspective() == Perspective::IS_SERVER; |
| // IETF QUIC long headers include a length on client 0RTT packets. |
| QuicVariableLengthIntegerLength length_length = |
| VARIABLE_LENGTH_INTEGER_LENGTH_0; |
| if (framer_->perspective() == Perspective::IS_CLIENT) { |
| length_length = VARIABLE_LENGTH_INTEGER_LENGTH_2; |
| } |
| if (!QuicVersionHasLongHeaderLengths(framer_->transport_version())) { |
| length_length = VARIABLE_LENGTH_INTEGER_LENGTH_0; |
| } |
| const size_t packet_header_size = GetPacketHeaderSize( |
| framer_->transport_version(), GetDestinationConnectionIdLength(), |
| // Assume CID lengths don't change, but version may be present. |
| GetSourceConnectionIdLength(), kIncludeVersion, may_include_nonce, |
| PACKET_4BYTE_PACKET_NUMBER, |
| // No Retry token on packets containing application data. |
| VARIABLE_LENGTH_INTEGER_LENGTH_0, 0, length_length); |
| // This is the largest possible message payload when the length field is |
| // omitted. |
| const QuicPacketLength largest_payload = |
| max_plaintext_size_ - |
| std::min(max_plaintext_size_, packet_header_size + kQuicFrameTypeSize); |
| // This must always be less than or equal to GetCurrentLargestMessagePayload. |
| DCHECK_LE(largest_payload, GetCurrentLargestMessagePayload()); |
| return largest_payload; |
| } |
| |
| bool QuicPacketCreator::HasIetfLongHeader() const { |
| return VersionHasIetfInvariantHeader(framer_->transport_version()) && |
| packet_.encryption_level < ENCRYPTION_FORWARD_SECURE; |
| } |
| |
| // static |
| size_t QuicPacketCreator::MinPlaintextPacketSize( |
| const ParsedQuicVersion& version) { |
| if (!version.HasHeaderProtection()) { |
| return 0; |
| } |
| // Header protection samples 16 bytes of ciphertext starting 4 bytes after the |
| // packet number. In IETF QUIC, all AEAD algorithms have a 16-byte auth tag |
| // (i.e. the ciphertext is 16 bytes larger than the plaintext). Since packet |
| // numbers could be as small as 1 byte, but the sample starts 4 bytes after |
| // the packet number, at least 3 bytes of plaintext are needed to make sure |
| // that there is enough ciphertext to sample. |
| // |
| // Google QUIC crypto uses different AEAD algorithms - in particular the auth |
| // tags are only 12 bytes instead of 16 bytes. Since the auth tag is 4 bytes |
| // shorter, 4 more bytes of plaintext are needed to guarantee there is enough |
| // ciphertext to sample. |
| // |
| // This method could check for PROTOCOL_TLS1_3 vs PROTOCOL_QUIC_CRYPTO and |
| // return 3 when TLS 1.3 is in use (the use of IETF vs Google QUIC crypters is |
| // determined based on the handshake protocol used). However, even when TLS |
| // 1.3 is used, unittests still use NullEncrypter/NullDecrypter (and other |
| // test crypters) which also only use 12 byte tags. |
| // |
| // TODO(nharper): Set this based on the handshake protocol in use. |
| return 7; |
| } |
| |
| QuicPacketNumber QuicPacketCreator::NextSendingPacketNumber() const { |
| if (!packet_number().IsInitialized()) { |
| return framer_->first_sending_packet_number(); |
| } |
| return packet_number() + 1; |
| } |
| |
| #undef ENDPOINT // undef for jumbo builds |
| } // namespace quic |
