blob: cc4f50ed50e84c0544c9c19075e0e009b23be88b [file] [log] [blame]
// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "net/third_party/quiche/src/quic/core/quic_packet_creator.h"
#include <algorithm>
#include <cstdint>
#include "base/macros.h"
#include "net/third_party/quiche/src/quic/core/crypto/crypto_protocol.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/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_string.h"
#include "net/third_party/quiche/src/quic/platform/api/quic_string_piece.h"
namespace quic {
#define ENDPOINT \
(framer_->perspective() == Perspective::IS_SERVER ? "Server: " : "Client: ")
QuicPacketCreator::QuicPacketCreator(QuicConnectionId connection_id,
QuicFramer* framer,
DelegateInterface* delegate)
: QuicPacketCreator(connection_id,
framer,
QuicRandom::GetInstance(),
delegate) {}
QuicPacketCreator::QuicPacketCreator(QuicConnectionId 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),
connection_id_length_(PACKET_8BYTE_CONNECTION_ID),
packet_size_(0),
connection_id_(connection_id),
packet_(QuicPacketNumber(),
PACKET_1BYTE_PACKET_NUMBER,
nullptr,
0,
false,
false),
long_header_type_(HANDSHAKE),
pending_padding_bytes_(0),
needs_full_padding_(false),
can_set_transmission_type_(false),
set_transmission_type_for_next_frame_(
GetQuicReloadableFlag(quic_set_transmission_type_for_next_frame)) {
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_);
}
// 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_LE(framer_->transport_version(), QUIC_VERSION_43);
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::ConsumeData(QuicStreamId id,
size_t write_length,
size_t iov_offset,
QuicStreamOffset offset,
bool fin,
bool needs_full_padding,
TransmissionType transmission_type,
QuicFrame* frame) {
if (!HasRoomForStreamFrame(id, offset, write_length - iov_offset)) {
return false;
}
CreateStreamFrame(id, write_length, iov_offset, offset, fin, frame);
// Explicitly disallow multi-packet CHLOs.
if (FLAGS_quic_enforce_single_packet_chlo &&
StreamFrameStartsWithChlo(frame->stream_frame) &&
frame->stream_frame.data_length < write_length) {
const QuicString 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: " << write_length;
delegate_->OnUnrecoverableError(QUIC_CRYPTO_CHLO_TOO_LARGE, error_details,
ConnectionCloseSource::FROM_SELF);
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_connetion_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,
QuicStreamOffset offset) {
return GetPacketHeaderSize(version, destination_connection_id_length,
source_connection_id_length, include_version,
include_diversification_nonce,
packet_number_length) +
// Assumes this is packet with a aingle 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,
kMaxPacketSize);
}
void QuicPacketCreator::CreateStreamFrame(QuicStreamId id,
size_t write_length,
size_t iov_offset,
QuicStreamOffset offset,
bool fin,
QuicFrame* frame) {
const size_t data_size = write_length - iov_offset;
DCHECK_GT(
max_packet_length_,
StreamFramePacketOverhead(
framer_->transport_version(), GetDestinationConnectionIdLength(),
GetSourceConnectionIdLength(), kIncludeVersion,
IncludeNonceInPublicHeader(), PACKET_6BYTE_PACKET_NUMBER, 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);
if (iov_offset == write_length) {
QUIC_BUG_IF(!fin) << "Creating a stream frame with no data or fin.";
// Create a new packet for the fin, if necessary.
*frame = QuicFrame(QuicStreamFrame(id, true, offset, QuicStringPiece()));
return;
}
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));
}
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[kMaxPacketSize];
char* serialized_packet_buffer = delegate_->GetPacketBuffer();
if (serialized_packet_buffer == nullptr) {
serialized_packet_buffer = stack_buffer;
}
SerializePacket(serialized_packet_buffer, kMaxPacketSize);
OnSerializedPacket();
}
void QuicPacketCreator::OnSerializedPacket() {
if (packet_.encrypted_buffer == nullptr) {
const QuicString error_details = "Failed to SerializePacket.";
QUIC_BUG << error_details;
delegate_->OnUnrecoverableError(QUIC_FAILED_TO_SERIALIZE_PACKET,
error_details,
ConnectionCloseSource::FROM_SELF);
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();
if (!can_set_transmission_type_ || ShouldSetTransmissionTypeForNextFrame()) {
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[kMaxPacketSize];
char* encrypted_buffer = delegate_->GetPacketBuffer();
if (encrypted_buffer == nullptr) {
encrypted_buffer = stack_buffer;
}
QuicDataWriter writer(kMaxPacketSize, encrypted_buffer,
framer_->endianness());
if (!framer_->AppendPacketHeader(header, &writer)) {
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;
const size_t min_frame_size = QuicFramer::GetMinStreamFrameSize(
framer_->transport_version(), id, stream_offset,
/* last_frame_in_packet= */ true, remaining_data_size);
const size_t available_size =
max_plaintext_size_ - writer.length() - min_frame_size;
const size_t bytes_consumed =
std::min<size_t>(available_size, remaining_data_size);
const bool set_fin = fin && (bytes_consumed == remaining_data_size);
QuicStreamFrame frame(id, set_fin, stream_offset, bytes_consumed);
QUIC_DVLOG(1) << ENDPOINT << "Adding frame: " << frame;
// TODO(ianswett): AppendTypeByte and AppendStreamFrame could be optimized
// into one method that takes a QuicStreamFrame, if warranted.
if (!framer_->AppendTypeByte(QuicFrame(frame),
/* no stream frame length */ true, &writer)) {
QUIC_BUG << "AppendTypeByte failed";
return;
}
if (!framer_->AppendStreamFrame(frame, /* no stream frame length */ true,
&writer)) {
QUIC_BUG << "AppendStreamFrame failed";
return;
}
if (ShouldSetTransmissionTypeForNextFrame()) {
QUIC_RELOADABLE_FLAG_COUNT_N(quic_set_transmission_type_for_next_frame, 1,
2);
packet_.transmission_type = transmission_type;
}
size_t encrypted_length = framer_->EncryptInPlace(
packet_.encryption_level, packet_.packet_number,
GetStartOfEncryptedData(framer_->transport_version(), header),
writer.length(), kMaxPacketSize, 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_data.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 (framer_->transport_version() == QUIC_VERSION_99) {
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_ = GetPacketHeaderSize(
framer_->transport_version(), GetDestinationConnectionIdLength(),
GetSourceConnectionIdLength(), IncludeVersionInHeader(),
IncludeNonceInPublicHeader(), GetPacketNumberLength());
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();
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_);
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,
const ParsedQuicVersionVector& supported_versions) {
DCHECK_EQ(Perspective::IS_SERVER, framer_->perspective());
std::unique_ptr<QuicEncryptedPacket> encrypted =
QuicFramer::BuildVersionNegotiationPacket(connection_id_, ietf_quic,
supported_versions);
DCHECK(encrypted);
DCHECK_GE(max_packet_length_, encrypted->length());
return encrypted;
}
OwningSerializedPacketPointer
QuicPacketCreator::SerializeConnectivityProbingPacket() {
QUIC_BUG_IF(framer_->transport_version() == QUIC_VERSION_99)
<< "Must not be version 99 to serialize padded ping connectivity probe";
QuicPacketHeader header;
// FillPacketHeader increments packet_number_.
FillPacketHeader(&header);
std::unique_ptr<char[]> buffer(new char[kMaxPacketSize]);
size_t length = framer_->BuildConnectivityProbingPacket(header, buffer.get(),
max_plaintext_size_);
DCHECK(length);
const size_t encrypted_length = framer_->EncryptInPlace(
packet_.encryption_level, packet_.packet_number,
GetStartOfEncryptedData(framer_->transport_version(), header), length,
kMaxPacketSize, 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(framer_->transport_version() != QUIC_VERSION_99)
<< "Must be version 99 to serialize path challenge connectivity probe, "
"is version "
<< framer_->transport_version();
QuicPacketHeader header;
// FillPacketHeader increments packet_number_.
FillPacketHeader(&header);
std::unique_ptr<char[]> buffer(new char[kMaxPacketSize]);
size_t length = framer_->BuildPaddedPathChallengePacket(
header, buffer.get(), max_plaintext_size_, payload, random_);
DCHECK(length);
const size_t encrypted_length = framer_->EncryptInPlace(
packet_.encryption_level, packet_.packet_number,
GetStartOfEncryptedData(framer_->transport_version(), header), length,
kMaxPacketSize, 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(framer_->transport_version() != QUIC_VERSION_99)
<< "Must be version 99 to serialize path response connectivity probe, is "
"version "
<< framer_->transport_version();
QuicPacketHeader header;
// FillPacketHeader increments packet_number_.
FillPacketHeader(&header);
std::unique_ptr<char[]> buffer(new char[kMaxPacketSize]);
size_t length = framer_->BuildPathResponsePacket(
header, buffer.get(), max_plaintext_size_, payloads, is_padded);
DCHECK(length);
const size_t encrypted_length = framer_->EncryptInPlace(
packet_.encryption_level, packet_.packet_number,
GetStartOfEncryptedData(framer_->transport_version(), header), length,
kMaxPacketSize, 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);
}
QuicConnectionIdLength QuicPacketCreator::GetDestinationConnectionIdLength()
const {
if (framer_->transport_version() > QUIC_VERSION_43) {
// Packets sent by client always include destination connection ID, and
// those sent by the server do not include destination connection ID.
return framer_->perspective() == Perspective::IS_CLIENT
? PACKET_8BYTE_CONNECTION_ID
: PACKET_0BYTE_CONNECTION_ID;
}
return connection_id_length_;
}
QuicConnectionIdLength QuicPacketCreator::GetSourceConnectionIdLength() const {
// Long header packets sent by server include source connection ID.
if (HasIetfLongHeader() && framer_->perspective() == Perspective::IS_SERVER) {
return PACKET_8BYTE_CONNECTION_ID;
}
return PACKET_0BYTE_CONNECTION_ID;
}
QuicPacketNumberLength QuicPacketCreator::GetPacketNumberLength() const {
if (HasIetfLongHeader() && framer_->transport_version() != QUIC_VERSION_99) {
return PACKET_4BYTE_PACKET_NUMBER;
}
return packet_.packet_number_length;
}
void QuicPacketCreator::FillPacketHeader(QuicPacketHeader* header) {
header->destination_connection_id = connection_id_;
header->destination_connection_id_length = GetDestinationConnectionIdLength();
header->source_connection_id = connection_id_;
header->source_connection_id_length = GetSourceConnectionIdLength();
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;
}
if (!packet_.packet_number.IsInitialized()) {
packet_.packet_number = framer_->first_sending_packet_number();
} else {
++packet_.packet_number;
}
header->packet_number = packet_.packet_number;
header->packet_number_length = GetPacketNumberLength();
if (!HasIetfLongHeader()) {
return;
}
header->long_packet_type = long_header_type_;
}
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 &&
frame.stream_frame.stream_id !=
QuicUtils::GetCryptoStreamId(framer_->transport_version()) &&
packet_.encryption_level == ENCRYPTION_NONE) {
const QuicString error_details =
"Cannot send stream data without encryption.";
QUIC_BUG << error_details;
delegate_->OnUnrecoverableError(
QUIC_ATTEMPT_TO_SEND_UNENCRYPTED_STREAM_DATA, error_details,
ConnectionCloseSource::FROM_SELF);
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)) {
if (packet_.retransmittable_frames.empty()) {
packet_.retransmittable_frames.reserve(2);
}
packet_.retransmittable_frames.push_back(frame);
queued_frames_.push_back(frame);
if (frame.type == STREAM_FRAME &&
frame.stream_frame.stream_id ==
QuicUtils::GetCryptoStreamId(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 (ShouldSetTransmissionTypeForNextFrame() &&
QuicUtils::IsRetransmittableFrame(frame.type)) {
QUIC_RELOADABLE_FLAG_COUNT_N(quic_set_transmission_type_for_next_frame, 2,
2);
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;
}
if (!needs_full_padding_ && pending_padding_bytes_ == 0) {
// Do not need padding.
return;
}
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;
}
bool success =
AddFrame(QuicFrame(QuicPaddingFrame(packet_.num_padding_bytes)), false,
packet_.transmission_type);
DCHECK(success);
}
bool QuicPacketCreator::IncludeNonceInPublicHeader() const {
return have_diversification_nonce_ &&
packet_.encryption_level == ENCRYPTION_INITIAL;
}
bool QuicPacketCreator::IncludeVersionInHeader() const {
if (framer_->transport_version() > QUIC_VERSION_43) {
return packet_.encryption_level < ENCRYPTION_FORWARD_SECURE;
}
return send_version_in_packet_;
}
void QuicPacketCreator::AddPendingPadding(QuicByteCount size) {
pending_padding_bytes_ += size;
}
bool QuicPacketCreator::StreamFrameStartsWithChlo(
const QuicStreamFrame& frame) const {
if (framer_->perspective() == Perspective::IS_SERVER ||
frame.stream_id !=
QuicUtils::GetCryptoStreamId(framer_->transport_version()) ||
frame.data_length < sizeof(kCHLO)) {
return false;
}
return framer_->StartsWithChlo(frame.stream_id, frame.offset);
}
void QuicPacketCreator::SetConnectionIdLength(QuicConnectionIdLength length) {
DCHECK(framer_->perspective() == Perspective::IS_SERVER ||
length != PACKET_0BYTE_CONNECTION_ID);
connection_id_length_ = length;
}
void QuicPacketCreator::SetTransmissionType(TransmissionType type) {
DCHECK(can_set_transmission_type_);
if (!ShouldSetTransmissionTypeForNextFrame()) {
QUIC_DVLOG_IF(1, type != packet_.transmission_type)
<< ENDPOINT << "Setting Transmission type to "
<< QuicUtils::TransmissionTypeToString(type);
packet_.transmission_type = type;
}
}
void QuicPacketCreator::SetLongHeaderType(QuicLongHeaderType type) {
long_header_type_ = type;
}
QuicPacketLength QuicPacketCreator::GetLargestMessagePayload() const {
if (framer_->transport_version() <= QUIC_VERSION_44) {
return 0;
}
const size_t packet_header_size = GetPacketHeaderSize(
framer_->transport_version(), GetDestinationConnectionIdLength(),
GetSourceConnectionIdLength(), IncludeVersionInHeader(),
IncludeNonceInPublicHeader(), GetPacketNumberLength());
// 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);
}
bool QuicPacketCreator::HasIetfLongHeader() const {
return framer_->transport_version() > QUIC_VERSION_43 &&
packet_.encryption_level < ENCRYPTION_FORWARD_SECURE;
}
#undef ENDPOINT // undef for jumbo builds
} // namespace quic