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quiche / quiche / 3e6cf91c2f41a1ab3903736bd9c2073de1e32ac1 / . / quic / core / quic_framer.cc
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// 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_framer.h"
#include <cstddef>
#include <cstdint>
#include <limits>
#include <memory>
#include <string>
#include <utility>
#include "absl/base/attributes.h"
#include "absl/base/macros.h"
#include "absl/base/optimization.h"
#include "absl/strings/escaping.h"
#include "absl/strings/numbers.h"
#include "absl/strings/str_cat.h"
#include "absl/strings/str_split.h"
#include "absl/strings/string_view.h"
#include "quic/core/crypto/crypto_framer.h"
#include "quic/core/crypto/crypto_handshake.h"
#include "quic/core/crypto/crypto_handshake_message.h"
#include "quic/core/crypto/crypto_protocol.h"
#include "quic/core/crypto/crypto_utils.h"
#include "quic/core/crypto/null_decrypter.h"
#include "quic/core/crypto/null_encrypter.h"
#include "quic/core/crypto/quic_decrypter.h"
#include "quic/core/crypto/quic_encrypter.h"
#include "quic/core/crypto/quic_random.h"
#include "quic/core/frames/quic_ack_frequency_frame.h"
#include "quic/core/quic_connection_id.h"
#include "quic/core/quic_constants.h"
#include "quic/core/quic_data_reader.h"
#include "quic/core/quic_data_writer.h"
#include "quic/core/quic_error_codes.h"
#include "quic/core/quic_packets.h"
#include "quic/core/quic_socket_address_coder.h"
#include "quic/core/quic_stream_frame_data_producer.h"
#include "quic/core/quic_time.h"
#include "quic/core/quic_types.h"
#include "quic/core/quic_utils.h"
#include "quic/core/quic_versions.h"
#include "quic/platform/api/quic_bug_tracker.h"
#include "quic/platform/api/quic_client_stats.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_stack_trace.h"
#include "common/quiche_text_utils.h"
namespace quic {
namespace {
#define ENDPOINT \
(perspective_ == Perspective::IS_SERVER ? "Server: " : "Client: ")
// Number of bits the packet number length bits are shifted from the right
// edge of the header.
const uint8_t kPublicHeaderSequenceNumberShift = 4;
// There are two interpretations for the Frame Type byte in the QUIC protocol,
// resulting in two Frame Types: Special Frame Types and Regular Frame Types.
//
// Regular Frame Types use the Frame Type byte simply. Currently defined
// Regular Frame Types are:
// Padding : 0b 00000000 (0x00)
// ResetStream : 0b 00000001 (0x01)
// ConnectionClose : 0b 00000010 (0x02)
// GoAway : 0b 00000011 (0x03)
// WindowUpdate : 0b 00000100 (0x04)
// Blocked : 0b 00000101 (0x05)
//
// Special Frame Types encode both a Frame Type and corresponding flags
// all in the Frame Type byte. Currently defined Special Frame Types
// are:
// Stream : 0b 1xxxxxxx
// Ack : 0b 01xxxxxx
//
// Semantics of the flag bits above (the x bits) depends on the frame type.
// Masks to determine if the frame type is a special use
// and for specific special frame types.
const uint8_t kQuicFrameTypeBrokenMask = 0xE0; // 0b 11100000
const uint8_t kQuicFrameTypeSpecialMask = 0xC0; // 0b 11000000
const uint8_t kQuicFrameTypeStreamMask = 0x80;
const uint8_t kQuicFrameTypeAckMask = 0x40;
static_assert(kQuicFrameTypeSpecialMask ==
(kQuicFrameTypeStreamMask | kQuicFrameTypeAckMask),
"Invalid kQuicFrameTypeSpecialMask");
// The stream type format is 1FDOOOSS, where
// F is the fin bit.
// D is the data length bit (0 or 2 bytes).
// OO/OOO are the size of the offset.
// SS is the size of the stream ID.
// Note that the stream encoding can not be determined by inspection. It can
// be determined only by knowing the QUIC Version.
// Stream frame relative shifts and masks for interpreting the stream flags.
// StreamID may be 1, 2, 3, or 4 bytes.
const uint8_t kQuicStreamIdShift = 2;
const uint8_t kQuicStreamIDLengthMask = 0x03;
// Offset may be 0, 2, 4, or 8 bytes.
const uint8_t kQuicStreamShift = 3;
const uint8_t kQuicStreamOffsetMask = 0x07;
// Data length may be 0 or 2 bytes.
const uint8_t kQuicStreamDataLengthShift = 1;
const uint8_t kQuicStreamDataLengthMask = 0x01;
// Fin bit may be set or not.
const uint8_t kQuicStreamFinShift = 1;
const uint8_t kQuicStreamFinMask = 0x01;
// The format is 01M0LLOO, where
// M if set, there are multiple ack blocks in the frame.
// LL is the size of the largest ack field.
// OO is the size of the ack blocks offset field.
// packet number size shift used in AckFrames.
const uint8_t kQuicSequenceNumberLengthNumBits = 2;
const uint8_t kActBlockLengthOffset = 0;
const uint8_t kLargestAckedOffset = 2;
// Acks may have only one ack block.
const uint8_t kQuicHasMultipleAckBlocksOffset = 5;
// Timestamps are 4 bytes followed by 2 bytes.
const uint8_t kQuicNumTimestampsLength = 1;
const uint8_t kQuicFirstTimestampLength = 4;
const uint8_t kQuicTimestampLength = 2;
// Gaps between packet numbers are 1 byte.
const uint8_t kQuicTimestampPacketNumberGapLength = 1;
// Maximum length of encoded error strings.
const int kMaxErrorStringLength = 256;
const uint8_t kConnectionIdLengthAdjustment = 3;
const uint8_t kDestinationConnectionIdLengthMask = 0xF0;
const uint8_t kSourceConnectionIdLengthMask = 0x0F;
// Returns the absolute value of the difference between |a| and |b|.
uint64_t Delta(uint64_t a, uint64_t b) {
// Since these are unsigned numbers, we can't just return abs(a - b)
if (a < b) {
return b - a;
}
return a - b;
}
uint64_t ClosestTo(uint64_t target, uint64_t a, uint64_t b) {
return (Delta(target, a) < Delta(target, b)) ? a : b;
}
QuicPacketNumberLength ReadSequenceNumberLength(uint8_t flags) {
switch (flags & PACKET_FLAGS_8BYTE_PACKET) {
case PACKET_FLAGS_8BYTE_PACKET:
return PACKET_6BYTE_PACKET_NUMBER;
case PACKET_FLAGS_4BYTE_PACKET:
return PACKET_4BYTE_PACKET_NUMBER;
case PACKET_FLAGS_2BYTE_PACKET:
return PACKET_2BYTE_PACKET_NUMBER;
case PACKET_FLAGS_1BYTE_PACKET:
return PACKET_1BYTE_PACKET_NUMBER;
default:
QUIC_BUG(quic_bug_10850_1) << "Unreachable case statement.";
return PACKET_6BYTE_PACKET_NUMBER;
}
}
QuicPacketNumberLength ReadAckPacketNumberLength(
uint8_t flags) {
switch (flags & PACKET_FLAGS_8BYTE_PACKET) {
case PACKET_FLAGS_8BYTE_PACKET:
return PACKET_6BYTE_PACKET_NUMBER;
case PACKET_FLAGS_4BYTE_PACKET:
return PACKET_4BYTE_PACKET_NUMBER;
case PACKET_FLAGS_2BYTE_PACKET:
return PACKET_2BYTE_PACKET_NUMBER;
case PACKET_FLAGS_1BYTE_PACKET:
return PACKET_1BYTE_PACKET_NUMBER;
default:
QUIC_BUG(quic_bug_10850_2) << "Unreachable case statement.";
return PACKET_6BYTE_PACKET_NUMBER;
}
}
uint8_t PacketNumberLengthToOnWireValue(
QuicPacketNumberLength packet_number_length) {
return packet_number_length - 1;
}
QuicPacketNumberLength GetShortHeaderPacketNumberLength(uint8_t type) {
QUICHE_DCHECK(!(type & FLAGS_LONG_HEADER));
return static_cast<QuicPacketNumberLength>((type & 0x03) + 1);
}
uint8_t LongHeaderTypeToOnWireValue(QuicLongHeaderType type) {
switch (type) {
case INITIAL:
return 0;
case ZERO_RTT_PROTECTED:
return 1 << 4;
case HANDSHAKE:
return 2 << 4;
case RETRY:
return 3 << 4;
case VERSION_NEGOTIATION:
return 0xF0; // Value does not matter
default:
QUIC_BUG(quic_bug_10850_3) << "Invalid long header type: " << type;
return 0xFF;
}
}
bool GetLongHeaderType(uint8_t type, QuicLongHeaderType* long_header_type) {
QUICHE_DCHECK((type & FLAGS_LONG_HEADER));
switch ((type & 0x30) >> 4) {
case 0:
*long_header_type = INITIAL;
break;
case 1:
*long_header_type = ZERO_RTT_PROTECTED;
break;
case 2:
*long_header_type = HANDSHAKE;
break;
case 3:
*long_header_type = RETRY;
break;
default:
QUIC_BUG(quic_bug_10850_4) << "Unreachable statement";
*long_header_type = INVALID_PACKET_TYPE;
return false;
}
return true;
}
QuicPacketNumberLength GetLongHeaderPacketNumberLength(uint8_t type) {
return static_cast<QuicPacketNumberLength>((type & 0x03) + 1);
}
// Used to get packet number space before packet gets decrypted.
PacketNumberSpace GetPacketNumberSpace(const QuicPacketHeader& header) {
switch (header.form) {
case GOOGLE_QUIC_PACKET:
QUIC_BUG(quic_bug_10850_5)
<< "Try to get packet number space of Google QUIC packet";
break;
case IETF_QUIC_SHORT_HEADER_PACKET:
return APPLICATION_DATA;
case IETF_QUIC_LONG_HEADER_PACKET:
switch (header.long_packet_type) {
case INITIAL:
return INITIAL_DATA;
case HANDSHAKE:
return HANDSHAKE_DATA;
case ZERO_RTT_PROTECTED:
return APPLICATION_DATA;
case VERSION_NEGOTIATION:
case RETRY:
case INVALID_PACKET_TYPE:
QUIC_BUG(quic_bug_10850_6)
<< "Try to get packet number space of long header type: "
<< QuicUtils::QuicLongHeaderTypetoString(header.long_packet_type);
break;
}
}
return NUM_PACKET_NUMBER_SPACES;
}
EncryptionLevel GetEncryptionLevel(const QuicPacketHeader& header) {
switch (header.form) {
case GOOGLE_QUIC_PACKET:
QUIC_BUG(quic_bug_10850_7)
<< "Cannot determine EncryptionLevel from Google QUIC header";
break;
case IETF_QUIC_SHORT_HEADER_PACKET:
return ENCRYPTION_FORWARD_SECURE;
case IETF_QUIC_LONG_HEADER_PACKET:
switch (header.long_packet_type) {
case INITIAL:
return ENCRYPTION_INITIAL;
case HANDSHAKE:
return ENCRYPTION_HANDSHAKE;
case ZERO_RTT_PROTECTED:
return ENCRYPTION_ZERO_RTT;
case VERSION_NEGOTIATION:
case RETRY:
case INVALID_PACKET_TYPE:
QUIC_BUG(quic_bug_10850_8)
<< "No encryption used with type "
<< QuicUtils::QuicLongHeaderTypetoString(header.long_packet_type);
}
}
return NUM_ENCRYPTION_LEVELS;
}
absl::string_view TruncateErrorString(absl::string_view error) {
if (error.length() <= kMaxErrorStringLength) {
return error;
}
return absl::string_view(error.data(), kMaxErrorStringLength);
}
size_t TruncatedErrorStringSize(const absl::string_view& error) {
if (error.length() < kMaxErrorStringLength) {
return error.length();
}
return kMaxErrorStringLength;
}
uint8_t GetConnectionIdLengthValue(QuicConnectionIdLength length) {
if (length == 0) {
return 0;
}
return static_cast<uint8_t>(length - kConnectionIdLengthAdjustment);
}
bool IsValidPacketNumberLength(QuicPacketNumberLength packet_number_length) {
size_t length = packet_number_length;
return length == 1 || length == 2 || length == 4 || length == 6 ||
length == 8;
}
bool IsValidFullPacketNumber(uint64_t full_packet_number,
ParsedQuicVersion version) {
return full_packet_number > 0 || version.HasIetfQuicFrames();
}
bool AppendIetfConnectionIds(bool version_flag,
bool use_length_prefix,
QuicConnectionId destination_connection_id,
QuicConnectionId source_connection_id,
QuicDataWriter* writer) {
if (!version_flag) {
return writer->WriteConnectionId(destination_connection_id);
}
if (use_length_prefix) {
return writer->WriteLengthPrefixedConnectionId(destination_connection_id) &&
writer->WriteLengthPrefixedConnectionId(source_connection_id);
}
// Compute connection ID length byte.
uint8_t dcil = GetConnectionIdLengthValue(
static_cast<QuicConnectionIdLength>(destination_connection_id.length()));
uint8_t scil = GetConnectionIdLengthValue(
static_cast<QuicConnectionIdLength>(source_connection_id.length()));
uint8_t connection_id_length = dcil << 4 | scil;
return writer->WriteUInt8(connection_id_length) &&
writer->WriteConnectionId(destination_connection_id) &&
writer->WriteConnectionId(source_connection_id);
}
enum class DroppedPacketReason {
// General errors
INVALID_PUBLIC_HEADER,
VERSION_MISMATCH,
// Version negotiation packet errors
INVALID_VERSION_NEGOTIATION_PACKET,
// Public reset packet errors, pre-v44
INVALID_PUBLIC_RESET_PACKET,
// Data packet errors
INVALID_PACKET_NUMBER,
INVALID_DIVERSIFICATION_NONCE,
DECRYPTION_FAILURE,
NUM_REASONS,
};
void RecordDroppedPacketReason(DroppedPacketReason reason) {
QUIC_CLIENT_HISTOGRAM_ENUM("QuicDroppedPacketReason", reason,
DroppedPacketReason::NUM_REASONS,
"The reason a packet was not processed. Recorded "
"each time such a packet is dropped");
}
PacketHeaderFormat GetIetfPacketHeaderFormat(uint8_t type_byte) {
return type_byte & FLAGS_LONG_HEADER ? IETF_QUIC_LONG_HEADER_PACKET
: IETF_QUIC_SHORT_HEADER_PACKET;
}
std::string GenerateErrorString(std::string initial_error_string,
QuicErrorCode quic_error_code) {
if (quic_error_code == QUIC_IETF_GQUIC_ERROR_MISSING) {
// QUIC_IETF_GQUIC_ERROR_MISSING is special -- it means not to encode
// the error value in the string.
return initial_error_string;
}
return absl::StrCat(std::to_string(static_cast<unsigned>(quic_error_code)),
":", initial_error_string);
}
} // namespace
QuicFramer::QuicFramer(const ParsedQuicVersionVector& supported_versions,
QuicTime creation_time,
Perspective perspective,
uint8_t expected_server_connection_id_length)
: visitor_(nullptr),
error_(QUIC_NO_ERROR),
last_serialized_server_connection_id_(EmptyQuicConnectionId()),
last_serialized_client_connection_id_(EmptyQuicConnectionId()),
version_(ParsedQuicVersion::Unsupported()),
supported_versions_(supported_versions),
decrypter_level_(ENCRYPTION_INITIAL),
alternative_decrypter_level_(NUM_ENCRYPTION_LEVELS),
alternative_decrypter_latch_(false),
perspective_(perspective),
validate_flags_(true),
process_timestamps_(false),
creation_time_(creation_time),
last_timestamp_(QuicTime::Delta::Zero()),
support_key_update_for_connection_(false),
current_key_phase_bit_(false),
potential_peer_key_update_attempt_count_(0),
first_sending_packet_number_(FirstSendingPacketNumber()),
data_producer_(nullptr),
infer_packet_header_type_from_version_(perspective ==
Perspective::IS_CLIENT),
expected_server_connection_id_length_(
expected_server_connection_id_length),
expected_client_connection_id_length_(0),
supports_multiple_packet_number_spaces_(false),
last_written_packet_number_length_(0),
peer_ack_delay_exponent_(kDefaultAckDelayExponent),
local_ack_delay_exponent_(kDefaultAckDelayExponent),
current_received_frame_type_(0) {
QUICHE_DCHECK(!supported_versions.empty());
version_ = supported_versions_[0];
QUICHE_DCHECK(version_.IsKnown())
<< ParsedQuicVersionVectorToString(supported_versions_);
}
QuicFramer::~QuicFramer() {}
// static
size_t QuicFramer::GetMinStreamFrameSize(QuicTransportVersion version,
QuicStreamId stream_id,
QuicStreamOffset offset,
bool last_frame_in_packet,
size_t data_length) {
if (VersionHasIetfQuicFrames(version)) {
return kQuicFrameTypeSize + QuicDataWriter::GetVarInt62Len(stream_id) +
(last_frame_in_packet
? 0
: QuicDataWriter::GetVarInt62Len(data_length)) +
(offset != 0 ? QuicDataWriter::GetVarInt62Len(offset) : 0);
}
return kQuicFrameTypeSize + GetStreamIdSize(stream_id) +
GetStreamOffsetSize(offset) +
(last_frame_in_packet ? 0 : kQuicStreamPayloadLengthSize);
}
// static
size_t QuicFramer::GetMinCryptoFrameSize(QuicStreamOffset offset,
QuicPacketLength data_length) {
return kQuicFrameTypeSize + QuicDataWriter::GetVarInt62Len(offset) +
QuicDataWriter::GetVarInt62Len(data_length);
}
// static
size_t QuicFramer::GetMessageFrameSize(QuicTransportVersion version,
bool last_frame_in_packet,
QuicByteCount length) {
QUIC_BUG_IF(quic_bug_12975_1, !VersionSupportsMessageFrames(version))
<< "Try to serialize MESSAGE frame in " << version;
return kQuicFrameTypeSize +
(last_frame_in_packet ? 0 : QuicDataWriter::GetVarInt62Len(length)) +
length;
}
// static
size_t QuicFramer::GetMinAckFrameSize(QuicTransportVersion version,
const QuicAckFrame& ack_frame,
uint32_t local_ack_delay_exponent) {
if (VersionHasIetfQuicFrames(version)) {
// The minimal ack frame consists of the following fields: Largest
// Acknowledged, ACK Delay, 0 ACK Block Count, First ACK Block and ECN
// counts.
// Type byte + largest acked.
size_t min_size =
kQuicFrameTypeSize +
QuicDataWriter::GetVarInt62Len(LargestAcked(ack_frame).ToUint64());
// Ack delay.
min_size += QuicDataWriter::GetVarInt62Len(
ack_frame.ack_delay_time.ToMicroseconds() >> local_ack_delay_exponent);
// 0 ack block count.
min_size += QuicDataWriter::GetVarInt62Len(0);
// First ack block.
min_size += QuicDataWriter::GetVarInt62Len(
ack_frame.packets.Empty() ? 0
: ack_frame.packets.rbegin()->Length() - 1);
// ECN counts.
if (ack_frame.ecn_counters_populated &&
(ack_frame.ect_0_count || ack_frame.ect_1_count ||
ack_frame.ecn_ce_count)) {
min_size += (QuicDataWriter::GetVarInt62Len(ack_frame.ect_0_count) +
QuicDataWriter::GetVarInt62Len(ack_frame.ect_1_count) +
QuicDataWriter::GetVarInt62Len(ack_frame.ecn_ce_count));
}
return min_size;
}
return kQuicFrameTypeSize +
GetMinPacketNumberLength(LargestAcked(ack_frame)) +
kQuicDeltaTimeLargestObservedSize + kQuicNumTimestampsSize;
}
// static
size_t QuicFramer::GetStopWaitingFrameSize(
QuicPacketNumberLength packet_number_length) {
size_t min_size = kQuicFrameTypeSize + packet_number_length;
return min_size;
}
// static
size_t QuicFramer::GetRstStreamFrameSize(QuicTransportVersion version,
const QuicRstStreamFrame& frame) {
if (VersionHasIetfQuicFrames(version)) {
return QuicDataWriter::GetVarInt62Len(frame.stream_id) +
QuicDataWriter::GetVarInt62Len(frame.byte_offset) +
kQuicFrameTypeSize +
QuicDataWriter::GetVarInt62Len(frame.ietf_error_code);
}
return kQuicFrameTypeSize + kQuicMaxStreamIdSize + kQuicMaxStreamOffsetSize +
kQuicErrorCodeSize;
}
// static
size_t QuicFramer::GetConnectionCloseFrameSize(
QuicTransportVersion version,
const QuicConnectionCloseFrame& frame) {
if (!VersionHasIetfQuicFrames(version)) {
// Not IETF QUIC, return Google QUIC CONNECTION CLOSE frame size.
return kQuicFrameTypeSize + kQuicErrorCodeSize +
kQuicErrorDetailsLengthSize +
TruncatedErrorStringSize(frame.error_details);
}
// Prepend the extra error information to the string and get the result's
// length.
const size_t truncated_error_string_size = TruncatedErrorStringSize(
GenerateErrorString(frame.error_details, frame.quic_error_code));
const size_t frame_size =
truncated_error_string_size +
QuicDataWriter::GetVarInt62Len(truncated_error_string_size) +
kQuicFrameTypeSize +
QuicDataWriter::GetVarInt62Len(frame.wire_error_code);
if (frame.close_type == IETF_QUIC_APPLICATION_CONNECTION_CLOSE) {
return frame_size;
}
// The Transport close frame has the transport_close_frame_type, so include
// its length.
return frame_size +
QuicDataWriter::GetVarInt62Len(frame.transport_close_frame_type);
}
// static
size_t QuicFramer::GetMinGoAwayFrameSize() {
return kQuicFrameTypeSize + kQuicErrorCodeSize + kQuicErrorDetailsLengthSize +
kQuicMaxStreamIdSize;
}
// static
size_t QuicFramer::GetWindowUpdateFrameSize(
QuicTransportVersion version,
const QuicWindowUpdateFrame& frame) {
if (!VersionHasIetfQuicFrames(version)) {
return kQuicFrameTypeSize + kQuicMaxStreamIdSize + kQuicMaxStreamOffsetSize;
}
if (frame.stream_id == QuicUtils::GetInvalidStreamId(version)) {
// Frame would be a MAX DATA frame, which has only a Maximum Data field.
return kQuicFrameTypeSize + QuicDataWriter::GetVarInt62Len(frame.max_data);
}
// Frame would be MAX STREAM DATA, has Maximum Stream Data and Stream ID
// fields.
return kQuicFrameTypeSize + QuicDataWriter::GetVarInt62Len(frame.max_data) +
QuicDataWriter::GetVarInt62Len(frame.stream_id);
}
// static
size_t QuicFramer::GetMaxStreamsFrameSize(QuicTransportVersion version,
const QuicMaxStreamsFrame& frame) {
if (!VersionHasIetfQuicFrames(version)) {
QUIC_BUG(quic_bug_10850_9)
<< "In version " << version
<< ", which does not support IETF Frames, and tried to serialize "
"MaxStreams Frame.";
}
return kQuicFrameTypeSize +
QuicDataWriter::GetVarInt62Len(frame.stream_count);
}
// static
size_t QuicFramer::GetStreamsBlockedFrameSize(
QuicTransportVersion version,
const QuicStreamsBlockedFrame& frame) {
if (!VersionHasIetfQuicFrames(version)) {
QUIC_BUG(quic_bug_10850_10)
<< "In version " << version
<< ", which does not support IETF frames, and tried to serialize "
"StreamsBlocked Frame.";
}
return kQuicFrameTypeSize +
QuicDataWriter::GetVarInt62Len(frame.stream_count);
}
// static
size_t QuicFramer::GetBlockedFrameSize(QuicTransportVersion version,
const QuicBlockedFrame& frame) {
if (!VersionHasIetfQuicFrames(version)) {
return kQuicFrameTypeSize + kQuicMaxStreamIdSize;
}
if (frame.stream_id == QuicUtils::GetInvalidStreamId(version)) {
// return size of IETF QUIC Blocked frame
return kQuicFrameTypeSize + QuicDataWriter::GetVarInt62Len(frame.offset);
}
// return size of IETF QUIC Stream Blocked frame.
return kQuicFrameTypeSize + QuicDataWriter::GetVarInt62Len(frame.offset) +
QuicDataWriter::GetVarInt62Len(frame.stream_id);
}
// static
size_t QuicFramer::GetStopSendingFrameSize(const QuicStopSendingFrame& frame) {
return kQuicFrameTypeSize + QuicDataWriter::GetVarInt62Len(frame.stream_id) +
QuicDataWriter::GetVarInt62Len(frame.ietf_error_code);
}
// static
size_t QuicFramer::GetAckFrequencyFrameSize(
const QuicAckFrequencyFrame& frame) {
return QuicDataWriter::GetVarInt62Len(IETF_ACK_FREQUENCY) +
QuicDataWriter::GetVarInt62Len(frame.sequence_number) +
QuicDataWriter::GetVarInt62Len(frame.packet_tolerance) +
QuicDataWriter::GetVarInt62Len(frame.max_ack_delay.ToMicroseconds()) +
// One byte for encoding boolean
1;
}
// static
size_t QuicFramer::GetPathChallengeFrameSize(
const QuicPathChallengeFrame& frame) {
return kQuicFrameTypeSize + sizeof(frame.data_buffer);
}
// static
size_t QuicFramer::GetPathResponseFrameSize(
const QuicPathResponseFrame& frame) {
return kQuicFrameTypeSize + sizeof(frame.data_buffer);
}
// static
size_t QuicFramer::GetRetransmittableControlFrameSize(
QuicTransportVersion version,
const QuicFrame& frame) {
switch (frame.type) {
case PING_FRAME:
// Ping has no payload.
return kQuicFrameTypeSize;
case RST_STREAM_FRAME:
return GetRstStreamFrameSize(version, *frame.rst_stream_frame);
case CONNECTION_CLOSE_FRAME:
return GetConnectionCloseFrameSize(version,
*frame.connection_close_frame);
case GOAWAY_FRAME:
return GetMinGoAwayFrameSize() +
TruncatedErrorStringSize(frame.goaway_frame->reason_phrase);
case WINDOW_UPDATE_FRAME:
// For IETF QUIC, this could be either a MAX DATA or MAX STREAM DATA.
// GetWindowUpdateFrameSize figures this out and returns the correct
// length.
return GetWindowUpdateFrameSize(version, *frame.window_update_frame);
case BLOCKED_FRAME:
return GetBlockedFrameSize(version, *frame.blocked_frame);
case NEW_CONNECTION_ID_FRAME:
return GetNewConnectionIdFrameSize(*frame.new_connection_id_frame);
case RETIRE_CONNECTION_ID_FRAME:
return GetRetireConnectionIdFrameSize(*frame.retire_connection_id_frame);
case NEW_TOKEN_FRAME:
return GetNewTokenFrameSize(*frame.new_token_frame);
case MAX_STREAMS_FRAME:
return GetMaxStreamsFrameSize(version, frame.max_streams_frame);
case STREAMS_BLOCKED_FRAME:
return GetStreamsBlockedFrameSize(version, frame.streams_blocked_frame);
case PATH_RESPONSE_FRAME:
return GetPathResponseFrameSize(*frame.path_response_frame);
case PATH_CHALLENGE_FRAME:
return GetPathChallengeFrameSize(*frame.path_challenge_frame);
case STOP_SENDING_FRAME:
return GetStopSendingFrameSize(*frame.stop_sending_frame);
case HANDSHAKE_DONE_FRAME:
// HANDSHAKE_DONE has no payload.
return kQuicFrameTypeSize;
case ACK_FREQUENCY_FRAME:
return GetAckFrequencyFrameSize(*frame.ack_frequency_frame);
case STREAM_FRAME:
case ACK_FRAME:
case STOP_WAITING_FRAME:
case MTU_DISCOVERY_FRAME:
case PADDING_FRAME:
case MESSAGE_FRAME:
case CRYPTO_FRAME:
case NUM_FRAME_TYPES:
QUICHE_DCHECK(false);
return 0;
}
// Not reachable, but some Chrome compilers can't figure that out. *sigh*
QUICHE_DCHECK(false);
return 0;
}
// static
size_t QuicFramer::GetStreamIdSize(QuicStreamId stream_id) {
// Sizes are 1 through 4 bytes.
for (int i = 1; i <= 4; ++i) {
stream_id >>= 8;
if (stream_id == 0) {
return i;
}
}
QUIC_BUG(quic_bug_10850_11) << "Failed to determine StreamIDSize.";
return 4;
}
// static
size_t QuicFramer::GetStreamOffsetSize(QuicStreamOffset offset) {
// 0 is a special case.
if (offset == 0) {
return 0;
}
// 2 through 8 are the remaining sizes.
offset >>= 8;
for (int i = 2; i <= 8; ++i) {
offset >>= 8;
if (offset == 0) {
return i;
}
}
QUIC_BUG(quic_bug_10850_12) << "Failed to determine StreamOffsetSize.";
return 8;
}
// static
size_t QuicFramer::GetNewConnectionIdFrameSize(
const QuicNewConnectionIdFrame& frame) {
return kQuicFrameTypeSize +
QuicDataWriter::GetVarInt62Len(frame.sequence_number) +
QuicDataWriter::GetVarInt62Len(frame.retire_prior_to) +
kConnectionIdLengthSize + frame.connection_id.length() +
sizeof(frame.stateless_reset_token);
}
// static
size_t QuicFramer::GetRetireConnectionIdFrameSize(
const QuicRetireConnectionIdFrame& frame) {
return kQuicFrameTypeSize +
QuicDataWriter::GetVarInt62Len(frame.sequence_number);
}
// static
size_t QuicFramer::GetNewTokenFrameSize(const QuicNewTokenFrame& frame) {
return kQuicFrameTypeSize +
QuicDataWriter::GetVarInt62Len(frame.token.length()) +
frame.token.length();
}
// TODO(nharper): Change this method to take a ParsedQuicVersion.
bool QuicFramer::IsSupportedTransportVersion(
const QuicTransportVersion version) const {
for (const ParsedQuicVersion& supported_version : supported_versions_) {
if (version == supported_version.transport_version) {
return true;
}
}
return false;
}
bool QuicFramer::IsSupportedVersion(const ParsedQuicVersion version) const {
for (const ParsedQuicVersion& supported_version : supported_versions_) {
if (version == supported_version) {
return true;
}
}
return false;
}
size_t QuicFramer::GetSerializedFrameLength(
const QuicFrame& frame,
size_t free_bytes,
bool first_frame,
bool last_frame,
QuicPacketNumberLength packet_number_length) {
// Prevent a rare crash reported in b/19458523.
if (frame.type == ACK_FRAME && frame.ack_frame == nullptr) {
QUIC_BUG(quic_bug_10850_13)
<< "Cannot compute the length of a null ack frame. free_bytes:"
<< free_bytes << " first_frame:" << first_frame
<< " last_frame:" << last_frame
<< " seq num length:" << packet_number_length;
set_error(QUIC_INTERNAL_ERROR);
visitor_->OnError(this);
return 0;
}
if (frame.type == PADDING_FRAME) {
if (frame.padding_frame.num_padding_bytes == -1) {
// Full padding to the end of the packet.
return free_bytes;
} else {
// Lite padding.
return free_bytes <
static_cast<size_t>(frame.padding_frame.num_padding_bytes)
? free_bytes
: frame.padding_frame.num_padding_bytes;
}
}
size_t frame_len =
ComputeFrameLength(frame, last_frame, packet_number_length);
if (frame_len <= free_bytes) {
// Frame fits within packet. Note that acks may be truncated.
return frame_len;
}
// Only truncate the first frame in a packet, so if subsequent ones go
// over, stop including more frames.
if (!first_frame) {
return 0;
}
bool can_truncate =
frame.type == ACK_FRAME &&
free_bytes >= GetMinAckFrameSize(version_.transport_version,
*frame.ack_frame,
local_ack_delay_exponent_);
if (can_truncate) {
// Truncate the frame so the packet will not exceed kMaxOutgoingPacketSize.
// Note that we may not use every byte of the writer in this case.
QUIC_DLOG(INFO) << ENDPOINT
<< "Truncating large frame, free bytes: " << free_bytes;
return free_bytes;
}
return 0;
}
QuicFramer::AckFrameInfo::AckFrameInfo()
: max_block_length(0), first_block_length(0), num_ack_blocks(0) {}
QuicFramer::AckFrameInfo::AckFrameInfo(const AckFrameInfo& other) = default;
QuicFramer::AckFrameInfo::~AckFrameInfo() {}
bool QuicFramer::WriteIetfLongHeaderLength(const QuicPacketHeader& header,
QuicDataWriter* writer,
size_t length_field_offset,
EncryptionLevel level) {
if (!QuicVersionHasLongHeaderLengths(transport_version()) ||
!header.version_flag || length_field_offset == 0) {
return true;
}
if (writer->length() < length_field_offset ||
writer->length() - length_field_offset <
kQuicDefaultLongHeaderLengthLength) {
set_detailed_error("Invalid length_field_offset.");
QUIC_BUG(quic_bug_10850_14) << "Invalid length_field_offset.";
return false;
}
size_t length_to_write = writer->length() - length_field_offset -
kQuicDefaultLongHeaderLengthLength;
// Add length of auth tag.
length_to_write = GetCiphertextSize(level, length_to_write);
QuicDataWriter length_writer(writer->length() - length_field_offset,
writer->data() + length_field_offset);
if (!length_writer.WriteVarInt62(length_to_write,
kQuicDefaultLongHeaderLengthLength)) {
set_detailed_error("Failed to overwrite long header length.");
QUIC_BUG(quic_bug_10850_15) << "Failed to overwrite long header length.";
return false;
}
return true;
}
size_t QuicFramer::BuildDataPacket(const QuicPacketHeader& header,
const QuicFrames& frames,
char* buffer,
size_t packet_length,
EncryptionLevel level) {
QUIC_BUG_IF(quic_bug_12975_2,
header.version_flag && version().HasIetfInvariantHeader() &&
header.long_packet_type == RETRY && !frames.empty())
<< "IETF RETRY packets cannot contain frames " << header;
QuicDataWriter writer(packet_length, buffer);
size_t length_field_offset = 0;
if (!AppendPacketHeader(header, &writer, &length_field_offset)) {
QUIC_BUG(quic_bug_10850_16) << "AppendPacketHeader failed";
return 0;
}
if (VersionHasIetfQuicFrames(transport_version())) {
if (AppendIetfFrames(frames, &writer) == 0) {
return 0;
}
if (!WriteIetfLongHeaderLength(header, &writer, length_field_offset,
level)) {
return 0;
}
return writer.length();
}
size_t i = 0;
for (const QuicFrame& frame : frames) {
// Determine if we should write stream frame length in header.
const bool last_frame_in_packet = i == frames.size() - 1;
if (!AppendTypeByte(frame, last_frame_in_packet, &writer)) {
QUIC_BUG(quic_bug_10850_17) << "AppendTypeByte failed";
return 0;
}
switch (frame.type) {
case PADDING_FRAME:
if (!AppendPaddingFrame(frame.padding_frame, &writer)) {
QUIC_BUG(quic_bug_10850_18)
<< "AppendPaddingFrame of "
<< frame.padding_frame.num_padding_bytes << " failed";
return 0;
}
break;
case STREAM_FRAME:
if (!AppendStreamFrame(frame.stream_frame, last_frame_in_packet,
&writer)) {
QUIC_BUG(quic_bug_10850_19) << "AppendStreamFrame failed";
return 0;
}
break;
case ACK_FRAME:
if (!AppendAckFrameAndTypeByte(*frame.ack_frame, &writer)) {
QUIC_BUG(quic_bug_10850_20)
<< "AppendAckFrameAndTypeByte failed: " << detailed_error_;
return 0;
}
break;
case STOP_WAITING_FRAME:
if (!AppendStopWaitingFrame(header, frame.stop_waiting_frame,
&writer)) {
QUIC_BUG(quic_bug_10850_21) << "AppendStopWaitingFrame failed";
return 0;
}
break;
case MTU_DISCOVERY_FRAME:
// MTU discovery frames are serialized as ping frames.
ABSL_FALLTHROUGH_INTENDED;
case PING_FRAME:
// Ping has no payload.
break;
case RST_STREAM_FRAME:
if (!AppendRstStreamFrame(*frame.rst_stream_frame, &writer)) {
QUIC_BUG(quic_bug_10850_22) << "AppendRstStreamFrame failed";
return 0;
}
break;
case CONNECTION_CLOSE_FRAME:
if (!AppendConnectionCloseFrame(*frame.connection_close_frame,
&writer)) {
QUIC_BUG(quic_bug_10850_23) << "AppendConnectionCloseFrame failed";
return 0;
}
break;
case GOAWAY_FRAME:
if (!AppendGoAwayFrame(*frame.goaway_frame, &writer)) {
QUIC_BUG(quic_bug_10850_24) << "AppendGoAwayFrame failed";
return 0;
}
break;
case WINDOW_UPDATE_FRAME:
if (!AppendWindowUpdateFrame(*frame.window_update_frame, &writer)) {
QUIC_BUG(quic_bug_10850_25) << "AppendWindowUpdateFrame failed";
return 0;
}
break;
case BLOCKED_FRAME:
if (!AppendBlockedFrame(*frame.blocked_frame, &writer)) {
QUIC_BUG(quic_bug_10850_26) << "AppendBlockedFrame failed";
return 0;
}
break;
case NEW_CONNECTION_ID_FRAME:
set_detailed_error(
"Attempt to append NEW_CONNECTION_ID frame and not in IETF QUIC.");
return RaiseError(QUIC_INTERNAL_ERROR);
case RETIRE_CONNECTION_ID_FRAME:
set_detailed_error(
"Attempt to append RETIRE_CONNECTION_ID frame and not in IETF "
"QUIC.");
return RaiseError(QUIC_INTERNAL_ERROR);
case NEW_TOKEN_FRAME:
set_detailed_error(
"Attempt to append NEW_TOKEN_ID frame and not in IETF QUIC.");
return RaiseError(QUIC_INTERNAL_ERROR);
case MAX_STREAMS_FRAME:
set_detailed_error(
"Attempt to append MAX_STREAMS frame and not in IETF QUIC.");
return RaiseError(QUIC_INTERNAL_ERROR);
case STREAMS_BLOCKED_FRAME:
set_detailed_error(
"Attempt to append STREAMS_BLOCKED frame and not in IETF QUIC.");
return RaiseError(QUIC_INTERNAL_ERROR);
case PATH_RESPONSE_FRAME:
set_detailed_error(
"Attempt to append PATH_RESPONSE frame and not in IETF QUIC.");
return RaiseError(QUIC_INTERNAL_ERROR);
case PATH_CHALLENGE_FRAME:
set_detailed_error(
"Attempt to append PATH_CHALLENGE frame and not in IETF QUIC.");
return RaiseError(QUIC_INTERNAL_ERROR);
case STOP_SENDING_FRAME:
set_detailed_error(
"Attempt to append STOP_SENDING frame and not in IETF QUIC.");
return RaiseError(QUIC_INTERNAL_ERROR);
case MESSAGE_FRAME:
if (!AppendMessageFrameAndTypeByte(*frame.message_frame,
last_frame_in_packet, &writer)) {
QUIC_BUG(quic_bug_10850_27) << "AppendMessageFrame failed";
return 0;
}
break;
case CRYPTO_FRAME:
if (!QuicVersionUsesCryptoFrames(version_.transport_version)) {
set_detailed_error(
"Attempt to append CRYPTO frame in version prior to 47.");
return RaiseError(QUIC_INTERNAL_ERROR);
}
if (!AppendCryptoFrame(*frame.crypto_frame, &writer)) {
QUIC_BUG(quic_bug_10850_28) << "AppendCryptoFrame failed";
return 0;
}
break;
case HANDSHAKE_DONE_FRAME:
// HANDSHAKE_DONE has no payload.
break;
default:
RaiseError(QUIC_INVALID_FRAME_DATA);
QUIC_BUG(quic_bug_10850_29) << "QUIC_INVALID_FRAME_DATA";
return 0;
}
++i;
}
if (!WriteIetfLongHeaderLength(header, &writer, length_field_offset, level)) {
return 0;
}
return writer.length();
}
size_t QuicFramer::AppendIetfFrames(const QuicFrames& frames,
QuicDataWriter* writer) {
size_t i = 0;
for (const QuicFrame& frame : frames) {
// Determine if we should write stream frame length in header.
const bool last_frame_in_packet = i == frames.size() - 1;
if (!AppendIetfFrameType(frame, last_frame_in_packet, writer)) {
QUIC_BUG(quic_bug_10850_30)
<< "AppendIetfFrameType failed: " << detailed_error();
return 0;
}
switch (frame.type) {
case PADDING_FRAME:
if (!AppendPaddingFrame(frame.padding_frame, writer)) {
QUIC_BUG(quic_bug_10850_31) << "AppendPaddingFrame of "
<< frame.padding_frame.num_padding_bytes
<< " failed: " << detailed_error();
return 0;
}
break;
case STREAM_FRAME:
if (!AppendStreamFrame(frame.stream_frame, last_frame_in_packet,
writer)) {
QUIC_BUG(quic_bug_10850_32)
<< "AppendStreamFrame " << frame.stream_frame
<< " failed: " << detailed_error();
return 0;
}
break;
case ACK_FRAME:
if (!AppendIetfAckFrameAndTypeByte(*frame.ack_frame, writer)) {
QUIC_BUG(quic_bug_10850_33)
<< "AppendIetfAckFrameAndTypeByte failed: " << detailed_error();
return 0;
}
break;
case STOP_WAITING_FRAME:
set_detailed_error(
"Attempt to append STOP WAITING frame in IETF QUIC.");
RaiseError(QUIC_INTERNAL_ERROR);
QUIC_BUG(quic_bug_10850_34) << detailed_error();
return 0;
case MTU_DISCOVERY_FRAME:
// MTU discovery frames are serialized as ping frames.
ABSL_FALLTHROUGH_INTENDED;
case PING_FRAME:
// Ping has no payload.
break;
case RST_STREAM_FRAME:
if (!AppendRstStreamFrame(*frame.rst_stream_frame, writer)) {
QUIC_BUG(quic_bug_10850_35)
<< "AppendRstStreamFrame failed: " << detailed_error();
return 0;
}
break;
case CONNECTION_CLOSE_FRAME:
if (!AppendIetfConnectionCloseFrame(*frame.connection_close_frame,
writer)) {
QUIC_BUG(quic_bug_10850_36)
<< "AppendIetfConnectionCloseFrame failed: " << detailed_error();
return 0;
}
break;
case GOAWAY_FRAME:
set_detailed_error("Attempt to append GOAWAY frame in IETF QUIC.");
RaiseError(QUIC_INTERNAL_ERROR);
QUIC_BUG(quic_bug_10850_37) << detailed_error();
return 0;
case WINDOW_UPDATE_FRAME:
// Depending on whether there is a stream ID or not, will be either a
// MAX STREAM DATA frame or a MAX DATA frame.
if (frame.window_update_frame->stream_id ==
QuicUtils::GetInvalidStreamId(transport_version())) {
if (!AppendMaxDataFrame(*frame.window_update_frame, writer)) {
QUIC_BUG(quic_bug_10850_38)
<< "AppendMaxDataFrame failed: " << detailed_error();
return 0;
}
} else {
if (!AppendMaxStreamDataFrame(*frame.window_update_frame, writer)) {
QUIC_BUG(quic_bug_10850_39)
<< "AppendMaxStreamDataFrame failed: " << detailed_error();
return 0;
}
}
break;
case BLOCKED_FRAME:
if (!AppendBlockedFrame(*frame.blocked_frame, writer)) {
QUIC_BUG(quic_bug_10850_40)
<< "AppendBlockedFrame failed: " << detailed_error();
return 0;
}
break;
case MAX_STREAMS_FRAME:
if (!AppendMaxStreamsFrame(frame.max_streams_frame, writer)) {
QUIC_BUG(quic_bug_10850_41)
<< "AppendMaxStreamsFrame failed: " << detailed_error();
return 0;
}
break;
case STREAMS_BLOCKED_FRAME:
if (!AppendStreamsBlockedFrame(frame.streams_blocked_frame, writer)) {
QUIC_BUG(quic_bug_10850_42)
<< "AppendStreamsBlockedFrame failed: " << detailed_error();
return 0;
}
break;
case NEW_CONNECTION_ID_FRAME:
if (!AppendNewConnectionIdFrame(*frame.new_connection_id_frame,
writer)) {
QUIC_BUG(quic_bug_10850_43)
<< "AppendNewConnectionIdFrame failed: " << detailed_error();
return 0;
}
break;
case RETIRE_CONNECTION_ID_FRAME:
if (!AppendRetireConnectionIdFrame(*frame.retire_connection_id_frame,
writer)) {
QUIC_BUG(quic_bug_10850_44)
<< "AppendRetireConnectionIdFrame failed: " << detailed_error();
return 0;
}
break;
case NEW_TOKEN_FRAME:
if (!AppendNewTokenFrame(*frame.new_token_frame, writer)) {
QUIC_BUG(quic_bug_10850_45)
<< "AppendNewTokenFrame failed: " << detailed_error();
return 0;
}
break;
case STOP_SENDING_FRAME:
if (!AppendStopSendingFrame(*frame.stop_sending_frame, writer)) {
QUIC_BUG(quic_bug_10850_46)
<< "AppendStopSendingFrame failed: " << detailed_error();
return 0;
}
break;
case PATH_CHALLENGE_FRAME:
if (!AppendPathChallengeFrame(*frame.path_challenge_frame, writer)) {
QUIC_BUG(quic_bug_10850_47)
<< "AppendPathChallengeFrame failed: " << detailed_error();
return 0;
}
break;
case PATH_RESPONSE_FRAME:
if (!AppendPathResponseFrame(*frame.path_response_frame, writer)) {
QUIC_BUG(quic_bug_10850_48)
<< "AppendPathResponseFrame failed: " << detailed_error();
return 0;
}
break;
case MESSAGE_FRAME:
if (!AppendMessageFrameAndTypeByte(*frame.message_frame,
last_frame_in_packet, writer)) {
QUIC_BUG(quic_bug_10850_49)
<< "AppendMessageFrame failed: " << detailed_error();
return 0;
}
break;
case CRYPTO_FRAME:
if (!AppendCryptoFrame(*frame.crypto_frame, writer)) {
QUIC_BUG(quic_bug_10850_50)
<< "AppendCryptoFrame failed: " << detailed_error();
return 0;
}
break;
case HANDSHAKE_DONE_FRAME:
// HANDSHAKE_DONE has no payload.
break;
case ACK_FREQUENCY_FRAME:
if (!AppendAckFrequencyFrame(*frame.ack_frequency_frame, writer)) {
QUIC_BUG(quic_bug_10850_51)
<< "AppendAckFrequencyFrame failed: " << detailed_error();
return 0;
}
break;
default:
set_detailed_error("Tried to append unknown frame type.");
RaiseError(QUIC_INVALID_FRAME_DATA);
QUIC_BUG(quic_bug_10850_52)
<< "QUIC_INVALID_FRAME_DATA: " << frame.type;
return 0;
}
++i;
}
return writer->length();
}
// static
std::unique_ptr<QuicEncryptedPacket> QuicFramer::BuildPublicResetPacket(
const QuicPublicResetPacket& packet) {
CryptoHandshakeMessage reset;
reset.set_tag(kPRST);
reset.SetValue(kRNON, packet.nonce_proof);
if (packet.client_address.host().address_family() !=
IpAddressFamily::IP_UNSPEC) {
// packet.client_address is non-empty.
QuicSocketAddressCoder address_coder(packet.client_address);
std::string serialized_address = address_coder.Encode();
if (serialized_address.empty()) {
return nullptr;
}
reset.SetStringPiece(kCADR, serialized_address);
}
if (!packet.endpoint_id.empty()) {
reset.SetStringPiece(kEPID, packet.endpoint_id);
}
const QuicData& reset_serialized = reset.GetSerialized();
size_t len = kPublicFlagsSize + packet.connection_id.length() +
reset_serialized.length();
std::unique_ptr<char[]> buffer(new char[len]);
QuicDataWriter writer(len, buffer.get());
uint8_t flags = static_cast<uint8_t>(PACKET_PUBLIC_FLAGS_RST |
PACKET_PUBLIC_FLAGS_8BYTE_CONNECTION_ID);
// This hack makes post-v33 public reset packet look like pre-v33 packets.
flags |= static_cast<uint8_t>(PACKET_PUBLIC_FLAGS_8BYTE_CONNECTION_ID_OLD);
if (!writer.WriteUInt8(flags)) {
return nullptr;
}
if (!writer.WriteConnectionId(packet.connection_id)) {
return nullptr;
}
if (!writer.WriteBytes(reset_serialized.data(), reset_serialized.length())) {
return nullptr;
}
return std::make_unique<QuicEncryptedPacket>(buffer.release(), len, true);
}
// static
size_t QuicFramer::GetMinStatelessResetPacketLength() {
// 5 bytes (40 bits) = 2 Fixed Bits (01) + 38 Unpredictable bits
return 5 + kStatelessResetTokenLength;
}
// static
std::unique_ptr<QuicEncryptedPacket> QuicFramer::BuildIetfStatelessResetPacket(
QuicConnectionId /*connection_id*/,
size_t received_packet_length,
StatelessResetToken stateless_reset_token) {
QUIC_DVLOG(1) << "Building IETF stateless reset packet.";
if (GetQuicRestartFlag(quic_fix_stateless_reset2)) {
if (received_packet_length <= GetMinStatelessResetPacketLength()) {
QUICHE_DLOG(ERROR)
<< "Tried to build stateless reset packet with received packet "
"length "
<< received_packet_length;
return nullptr;
}
// To ensure stateless reset is indistinguishable from a valid packet,
// include the max connection ID length.
size_t len = std::min(received_packet_length - 1,
GetMinStatelessResetPacketLength() + 1 +
kQuicMaxConnectionIdWithLengthPrefixLength);
std::unique_ptr<char[]> buffer(new char[len]);
QuicDataWriter writer(len, buffer.get());
// Append random bytes. This randomness only exists to prevent middleboxes
// from comparing the entire packet to a known value. Therefore it has no
// cryptographic use, and does not need a secure cryptographic pseudo-random
// number generator. It's therefore safe to use WriteInsecureRandomBytes.
if (!writer.WriteInsecureRandomBytes(QuicRandom::GetInstance(),
len - kStatelessResetTokenLength)) {
QUIC_BUG(362045737_2) << "Failed to append random bytes of length: "
<< len - kStatelessResetTokenLength;
return nullptr;
}
// Change first 2 fixed bits to 01.
buffer[0] &= ~FLAGS_LONG_HEADER;
buffer[0] |= FLAGS_FIXED_BIT;
// Append stateless reset token.
if (!writer.WriteBytes(&stateless_reset_token,
sizeof(stateless_reset_token))) {
QUIC_BUG(362045737_3) << "Failed to write stateless reset token";
return nullptr;
}
QUIC_RESTART_FLAG_COUNT(quic_fix_stateless_reset2);
return std::make_unique<QuicEncryptedPacket>(buffer.release(), len,
/*owns_buffer=*/true);
}
size_t len = kPacketHeaderTypeSize + kMinRandomBytesLengthInStatelessReset +
sizeof(stateless_reset_token);
std::unique_ptr<char[]> buffer(new char[len]);
QuicDataWriter writer(len, buffer.get());
uint8_t type = 0;
type |= FLAGS_FIXED_BIT;
type |= FLAGS_SHORT_HEADER_RESERVED_1;
type |= FLAGS_SHORT_HEADER_RESERVED_2;
type |= PacketNumberLengthToOnWireValue(PACKET_1BYTE_PACKET_NUMBER);
// Append type byte.
if (!writer.WriteUInt8(type)) {
return nullptr;
}
// Append random bytes. This randomness only exists to prevent middleboxes
// from comparing the entire packet to a known value. Therefore it has no
// cryptographic use, and does not need a secure cryptographic pseudo-random
// number generator. It's therefore safe to use WriteInsecureRandomBytes.
if (!writer.WriteInsecureRandomBytes(QuicRandom::GetInstance(),
kMinRandomBytesLengthInStatelessReset)) {
return nullptr;
}
// Append stateless reset token.
if (!writer.WriteBytes(&stateless_reset_token,
sizeof(stateless_reset_token))) {
return nullptr;
}
return std::make_unique<QuicEncryptedPacket>(buffer.release(), len, true);
}
// static
std::unique_ptr<QuicEncryptedPacket> QuicFramer::BuildVersionNegotiationPacket(
QuicConnectionId server_connection_id,
QuicConnectionId client_connection_id,
bool ietf_quic,
bool use_length_prefix,
const ParsedQuicVersionVector& versions) {
QUIC_CODE_COUNT(quic_build_version_negotiation);
if (use_length_prefix) {
QUICHE_DCHECK(ietf_quic);
QUIC_CODE_COUNT(quic_build_version_negotiation_ietf);
} else if (ietf_quic) {
QUIC_CODE_COUNT(quic_build_version_negotiation_old_ietf);
} else {
QUIC_CODE_COUNT(quic_build_version_negotiation_old_gquic);
}
ParsedQuicVersionVector wire_versions = versions;
// Add a version reserved for negotiation as suggested by the
// "Using Reserved Versions" section of draft-ietf-quic-transport.
if (wire_versions.empty()) {
// Ensure that version negotiation packets we send have at least two
// versions. This guarantees that, under all circumstances, all QUIC
// packets we send are at least 14 bytes long.
wire_versions = {QuicVersionReservedForNegotiation(),
QuicVersionReservedForNegotiation()};
} else {
// This is not uniformely distributed but is acceptable since no security
// depends on this randomness.
size_t version_index = 0;
const bool disable_randomness =
GetQuicFlag(FLAGS_quic_disable_version_negotiation_grease_randomness);
if (!disable_randomness) {
version_index =
QuicRandom::GetInstance()->RandUint64() % (wire_versions.size() + 1);
}
wire_versions.insert(wire_versions.begin() + version_index,
QuicVersionReservedForNegotiation());
}
if (ietf_quic) {
return BuildIetfVersionNegotiationPacket(
use_length_prefix, server_connection_id, client_connection_id,
wire_versions);
}
// The GQUIC encoding does not support encoding client connection IDs.
QUICHE_DCHECK(client_connection_id.IsEmpty());
// The GQUIC encoding does not support length-prefixed connection IDs.
QUICHE_DCHECK(!use_length_prefix);
QUICHE_DCHECK(!wire_versions.empty());
size_t len = kPublicFlagsSize + server_connection_id.length() +
wire_versions.size() * kQuicVersionSize;
std::unique_ptr<char[]> buffer(new char[len]);
QuicDataWriter writer(len, buffer.get());
uint8_t flags = static_cast<uint8_t>(
PACKET_PUBLIC_FLAGS_VERSION | PACKET_PUBLIC_FLAGS_8BYTE_CONNECTION_ID |
PACKET_PUBLIC_FLAGS_8BYTE_CONNECTION_ID_OLD);
if (!writer.WriteUInt8(flags)) {
return nullptr;
}
if (!writer.WriteConnectionId(server_connection_id)) {
return nullptr;
}
for (const ParsedQuicVersion& version : wire_versions) {
if (!writer.WriteUInt32(CreateQuicVersionLabel(version))) {
return nullptr;
}
}
return std::make_unique<QuicEncryptedPacket>(buffer.release(), len, true);
}
// static
std::unique_ptr<QuicEncryptedPacket>
QuicFramer::BuildIetfVersionNegotiationPacket(
bool use_length_prefix,
QuicConnectionId server_connection_id,
QuicConnectionId client_connection_id,
const ParsedQuicVersionVector& versions) {
QUIC_DVLOG(1) << "Building IETF version negotiation packet with"
<< (use_length_prefix ? "" : "out")
<< " length prefix, server_connection_id "
<< server_connection_id << " client_connection_id "
<< client_connection_id << " versions "
<< ParsedQuicVersionVectorToString(versions);
QUICHE_DCHECK(!versions.empty());
size_t len = kPacketHeaderTypeSize + kConnectionIdLengthSize +
client_connection_id.length() + server_connection_id.length() +
(versions.size() + 1) * kQuicVersionSize;
if (use_length_prefix) {
// When using length-prefixed connection IDs, packets carry two lengths
// instead of one.
len += kConnectionIdLengthSize;
}
std::unique_ptr<char[]> buffer(new char[len]);
QuicDataWriter writer(len, buffer.get());
// TODO(fayang): Randomly select a value for the type.
uint8_t type = static_cast<uint8_t>(FLAGS_LONG_HEADER | FLAGS_FIXED_BIT);
if (!writer.WriteUInt8(type)) {
return nullptr;
}
if (!writer.WriteUInt32(0)) {
return nullptr;
}
if (!AppendIetfConnectionIds(true, use_length_prefix, client_connection_id,
server_connection_id, &writer)) {
return nullptr;
}
for (const ParsedQuicVersion& version : versions) {
if (!writer.WriteUInt32(CreateQuicVersionLabel(version))) {
return nullptr;
}
}
return std::make_unique<QuicEncryptedPacket>(buffer.release(), len, true);
}
bool QuicFramer::ProcessPacket(const QuicEncryptedPacket& packet) {
QUICHE_DCHECK(!is_processing_packet_) << ENDPOINT << "Nested ProcessPacket";
is_processing_packet_ = true;
bool result = ProcessPacketInternal(packet);
is_processing_packet_ = false;
return result;
}
bool QuicFramer::ProcessPacketInternal(const QuicEncryptedPacket& packet) {
QuicDataReader reader(packet.data(), packet.length());
bool packet_has_ietf_packet_header = false;
if (infer_packet_header_type_from_version_) {
packet_has_ietf_packet_header = version_.HasIetfInvariantHeader();
} else if (!reader.IsDoneReading()) {
uint8_t type = reader.PeekByte();
packet_has_ietf_packet_header = QuicUtils::IsIetfPacketHeader(type);
}
if (packet_has_ietf_packet_header) {
QUIC_DVLOG(1) << ENDPOINT << "Processing IETF QUIC packet.";
}
visitor_->OnPacket();
QuicPacketHeader header;
if (!ProcessPublicHeader(&reader, packet_has_ietf_packet_header, &header)) {
QUICHE_DCHECK_NE("", detailed_error_);
QUIC_DVLOG(1) << ENDPOINT << "Unable to process public header. Error: "
<< detailed_error_;
QUICHE_DCHECK_NE("", detailed_error_);
RecordDroppedPacketReason(DroppedPacketReason::INVALID_PUBLIC_HEADER);
return RaiseError(QUIC_INVALID_PACKET_HEADER);
}
if (!visitor_->OnUnauthenticatedPublicHeader(header)) {
// The visitor suppresses further processing of the packet.
return true;
}
if (IsVersionNegotiation(header, packet_has_ietf_packet_header)) {
if (perspective_ == Perspective::IS_CLIENT) {
QUIC_DVLOG(1) << "Client received version negotiation packet";
return ProcessVersionNegotiationPacket(&reader, header);
} else {
QUIC_DLOG(ERROR) << "Server received version negotiation packet";
set_detailed_error("Server received version negotiation packet.");
return RaiseError(QUIC_INVALID_VERSION_NEGOTIATION_PACKET);
}
}
if (header.version_flag && header.version != version_) {
if (perspective_ == Perspective::IS_SERVER) {
if (!visitor_->OnProtocolVersionMismatch(header.version)) {
RecordDroppedPacketReason(DroppedPacketReason::VERSION_MISMATCH);
return true;
}
} else {
// A client received a packet of a different version but that packet is
// not a version negotiation packet. It is therefore invalid and dropped.
QUIC_DLOG(ERROR) << "Client received unexpected version "
<< ParsedQuicVersionToString(header.version)
<< " instead of " << ParsedQuicVersionToString(version_);
set_detailed_error("Client received unexpected version.");
return RaiseError(QUIC_INVALID_VERSION);
}
}
bool rv;
if (header.long_packet_type == RETRY) {
rv = ProcessRetryPacket(&reader, header);
} else if (header.reset_flag) {
rv = ProcessPublicResetPacket(&reader, header);
} else if (packet.length() <= kMaxIncomingPacketSize) {
// The optimized decryption algorithm implementations run faster when
// operating on aligned memory.
ABSL_CACHELINE_ALIGNED char buffer[kMaxIncomingPacketSize];
if (packet_has_ietf_packet_header) {
rv = ProcessIetfDataPacket(&reader, &header, packet, buffer,
ABSL_ARRAYSIZE(buffer));
} else {
rv = ProcessDataPacket(&reader, &header, packet, buffer,
ABSL_ARRAYSIZE(buffer));
}
} else {
std::unique_ptr<char[]> large_buffer(new char[packet.length()]);
if (packet_has_ietf_packet_header) {
rv = ProcessIetfDataPacket(&reader, &header, packet, large_buffer.get(),
packet.length());
} else {
rv = ProcessDataPacket(&reader, &header, packet, large_buffer.get(),
packet.length());
}
QUIC_BUG_IF(quic_bug_10850_53, rv)
<< "QUIC should never successfully process packets larger"
<< "than kMaxIncomingPacketSize. packet size:" << packet.length();
}
return rv;
}
bool QuicFramer::ProcessVersionNegotiationPacket(
QuicDataReader* reader,
const QuicPacketHeader& header) {
QUICHE_DCHECK_EQ(Perspective::IS_CLIENT, perspective_);
QuicVersionNegotiationPacket packet(
GetServerConnectionIdAsRecipient(header, perspective_));
// Try reading at least once to raise error if the packet is invalid.
do {
QuicVersionLabel version_label;
if (!ProcessVersionLabel(reader, &version_label)) {
set_detailed_error("Unable to read supported version in negotiation.");
RecordDroppedPacketReason(
DroppedPacketReason::INVALID_VERSION_NEGOTIATION_PACKET);
return RaiseError(QUIC_INVALID_VERSION_NEGOTIATION_PACKET);
}
ParsedQuicVersion parsed_version = ParseQuicVersionLabel(version_label);
if (parsed_version != UnsupportedQuicVersion()) {
packet.versions.push_back(parsed_version);
}
} while (!reader->IsDoneReading());
QUIC_DLOG(INFO) << ENDPOINT << "parsed version negotiation: "
<< ParsedQuicVersionVectorToString(packet.versions);
visitor_->OnVersionNegotiationPacket(packet);
return true;
}
bool QuicFramer::ProcessRetryPacket(QuicDataReader* reader,
const QuicPacketHeader& header) {
QUICHE_DCHECK_EQ(Perspective::IS_CLIENT, perspective_);
if (drop_incoming_retry_packets_) {
QUIC_DLOG(INFO) << "Ignoring received RETRY packet";
return true;
}
if (version_.UsesTls()) {
QUICHE_DCHECK(version_.HasLengthPrefixedConnectionIds()) << version_;
const size_t bytes_remaining = reader->BytesRemaining();
if (bytes_remaining <= kRetryIntegrityTagLength) {
set_detailed_error("Retry packet too short to parse integrity tag.");
return false;
}
const size_t retry_token_length =
bytes_remaining - kRetryIntegrityTagLength;
QUICHE_DCHECK_GT(retry_token_length, 0u);
absl::string_view retry_token;
if (!reader->ReadStringPiece(&retry_token, retry_token_length)) {
set_detailed_error("Failed to read retry token.");
return false;
}
absl::string_view retry_without_tag = reader->PreviouslyReadPayload();
absl::string_view integrity_tag = reader->ReadRemainingPayload();
QUICHE_DCHECK_EQ(integrity_tag.length(), kRetryIntegrityTagLength);
visitor_->OnRetryPacket(EmptyQuicConnectionId(),
header.source_connection_id, retry_token,
integrity_tag, retry_without_tag);
return true;
}
QuicConnectionId original_destination_connection_id;
if (version_.HasLengthPrefixedConnectionIds()) {
// Parse Original Destination Connection ID.
if (!reader->ReadLengthPrefixedConnectionId(
&original_destination_connection_id)) {
set_detailed_error("Unable to read Original Destination ConnectionId.");
return false;
}
} else {
// Parse Original Destination Connection ID Length.
uint8_t odcil = header.type_byte & 0xf;
if (odcil != 0) {
odcil += kConnectionIdLengthAdjustment;
}
// Parse Original Destination Connection ID.
if (!reader->ReadConnectionId(&original_destination_connection_id, odcil)) {
set_detailed_error("Unable to read Original Destination ConnectionId.");
return false;
}
}
if (!QuicUtils::IsConnectionIdValidForVersion(
original_destination_connection_id, transport_version())) {
set_detailed_error(
"Received Original Destination ConnectionId with invalid length.");
return false;
}
absl::string_view retry_token = reader->ReadRemainingPayload();
visitor_->OnRetryPacket(original_destination_connection_id,
header.source_connection_id, retry_token,
/*retry_integrity_tag=*/absl::string_view(),
/*retry_without_tag=*/absl::string_view());
return true;
}
// Seeks the current packet to check for a coalesced packet at the end.
// If the IETF length field only spans part of the outer packet,
// then there is a coalesced packet after this one.
void QuicFramer::MaybeProcessCoalescedPacket(
const QuicDataReader& encrypted_reader,
uint64_t remaining_bytes_length,
const QuicPacketHeader& header) {
if (header.remaining_packet_length >= remaining_bytes_length) {
// There is no coalesced packet.
return;
}
absl::string_view remaining_data = encrypted_reader.PeekRemainingPayload();
QUICHE_DCHECK_EQ(remaining_data.length(), remaining_bytes_length);
const char* coalesced_data =
remaining_data.data() + header.remaining_packet_length;
uint64_t coalesced_data_length =
remaining_bytes_length - header.remaining_packet_length;
QuicDataReader coalesced_reader(coalesced_data, coalesced_data_length);
QuicPacketHeader coalesced_header;
if (!ProcessIetfPacketHeader(&coalesced_reader, &coalesced_header)) {
// Some implementations pad their INITIAL packets by sending random invalid
// data after the INITIAL, and that is allowed by the specification. If we
// fail to parse a subsequent coalesced packet, simply ignore it.
QUIC_DLOG(INFO) << ENDPOINT
<< "Failed to parse received coalesced header of length "
<< coalesced_data_length
<< " with error: " << detailed_error_ << ": "
<< absl::BytesToHexString(absl::string_view(
coalesced_data, coalesced_data_length))
<< " previous header was " << header;
return;
}
if (coalesced_header.destination_connection_id !=
header.destination_connection_id) {
// Drop coalesced packets with mismatched connection IDs.
QUIC_DLOG(INFO) << ENDPOINT << "Received mismatched coalesced header "
<< coalesced_header << " previous header was " << header;
QUIC_CODE_COUNT(
quic_received_coalesced_packets_with_mismatched_connection_id);
return;
}
QuicEncryptedPacket coalesced_packet(coalesced_data, coalesced_data_length,
/*owns_buffer=*/false);
visitor_->OnCoalescedPacket(coalesced_packet);
}
bool QuicFramer::MaybeProcessIetfLength(QuicDataReader* encrypted_reader,
QuicPacketHeader* header) {
if (!QuicVersionHasLongHeaderLengths(header->version.transport_version) ||
header->form != IETF_QUIC_LONG_HEADER_PACKET ||
(header->long_packet_type != INITIAL &&
header->long_packet_type != HANDSHAKE &&
header->long_packet_type != ZERO_RTT_PROTECTED)) {
return true;
}
header->length_length = encrypted_reader->PeekVarInt62Length();
if (!encrypted_reader->ReadVarInt62(&header->remaining_packet_length)) {
set_detailed_error("Unable to read long header payload length.");
return RaiseError(QUIC_INVALID_PACKET_HEADER);
}
uint64_t remaining_bytes_length = encrypted_reader->BytesRemaining();
if (header->remaining_packet_length > remaining_bytes_length) {
set_detailed_error("Long header payload length longer than packet.");
return RaiseError(QUIC_INVALID_PACKET_HEADER);
}
MaybeProcessCoalescedPacket(*encrypted_reader, remaining_bytes_length,
*header);
if (!encrypted_reader->TruncateRemaining(header->remaining_packet_length)) {
set_detailed_error("Length TruncateRemaining failed.");
QUIC_BUG(quic_bug_10850_54) << "Length TruncateRemaining failed.";
return RaiseError(QUIC_INVALID_PACKET_HEADER);
}
return true;
}
bool QuicFramer::ProcessIetfDataPacket(QuicDataReader* encrypted_reader,
QuicPacketHeader* header,
const QuicEncryptedPacket& packet,
char* decrypted_buffer,
size_t buffer_length) {
QUICHE_DCHECK_NE(GOOGLE_QUIC_PACKET, header->form);
QUICHE_DCHECK(!header->has_possible_stateless_reset_token);
header->length_length = VARIABLE_LENGTH_INTEGER_LENGTH_0;
header->remaining_packet_length = 0;
if (header->form == IETF_QUIC_SHORT_HEADER_PACKET &&
perspective_ == Perspective::IS_CLIENT) {
// Peek possible stateless reset token. Will only be used on decryption
// failure.
absl::string_view remaining = encrypted_reader->PeekRemainingPayload();
if (remaining.length() >= sizeof(header->possible_stateless_reset_token)) {
header->has_possible_stateless_reset_token = true;
memcpy(&header->possible_stateless_reset_token,
&remaining.data()[remaining.length() -
sizeof(header->possible_stateless_reset_token)],
sizeof(header->possible_stateless_reset_token));
}
}
if (!MaybeProcessIetfLength(encrypted_reader, header)) {
return false;
}
absl::string_view associated_data;
std::vector<char> ad_storage;
QuicPacketNumber base_packet_number;
if (header->form == IETF_QUIC_SHORT_HEADER_PACKET ||
header->long_packet_type != VERSION_NEGOTIATION) {
QUICHE_DCHECK(header->form == IETF_QUIC_SHORT_HEADER_PACKET ||
header->long_packet_type == INITIAL ||
header->long_packet_type == HANDSHAKE ||
header->long_packet_type == ZERO_RTT_PROTECTED);
// Process packet number.
if (supports_multiple_packet_number_spaces_) {
PacketNumberSpace pn_space = GetPacketNumberSpace(*header);
if (pn_space == NUM_PACKET_NUMBER_SPACES) {
return RaiseError(QUIC_INVALID_PACKET_HEADER);
}
base_packet_number = largest_decrypted_packet_numbers_[pn_space];
} else {
base_packet_number = largest_packet_number_;
}
uint64_t full_packet_number;
bool hp_removal_failed = false;
if (version_.HasHeaderProtection()) {
if (!RemoveHeaderProtection(encrypted_reader, packet, header,
&full_packet_number, &ad_storage)) {
hp_removal_failed = true;
}
associated_data = absl::string_view(ad_storage.data(), ad_storage.size());
} else if (!ProcessAndCalculatePacketNumber(
encrypted_reader, header->packet_number_length,
base_packet_number, &full_packet_number)) {
set_detailed_error("Unable to read packet number.");
RecordDroppedPacketReason(DroppedPacketReason::INVALID_PACKET_NUMBER);
return RaiseError(QUIC_INVALID_PACKET_HEADER);
}
if (hp_removal_failed ||
!IsValidFullPacketNumber(full_packet_number, version())) {
if (IsIetfStatelessResetPacket(*header)) {
// This is a stateless reset packet.
QuicIetfStatelessResetPacket packet(
*header, header->possible_stateless_reset_token);
visitor_->OnAuthenticatedIetfStatelessResetPacket(packet);
return true;
}
if (hp_removal_failed) {
const EncryptionLevel decryption_level = GetEncryptionLevel(*header);
const bool has_decryption_key = decrypter_[decryption_level] != nullptr;
visitor_->OnUndecryptablePacket(
QuicEncryptedPacket(encrypted_reader->FullPayload()),
decryption_level, has_decryption_key);
RecordDroppedPacketReason(DroppedPacketReason::DECRYPTION_FAILURE);
set_detailed_error(absl::StrCat(
"Unable to decrypt ", EncryptionLevelToString(decryption_level),
" header protection", has_decryption_key ? "" : " (missing key)",
"."));
return RaiseError(QUIC_DECRYPTION_FAILURE);
}
RecordDroppedPacketReason(DroppedPacketReason::INVALID_PACKET_NUMBER);
set_detailed_error("packet numbers cannot be 0.");
return RaiseError(QUIC_INVALID_PACKET_HEADER);
}
header->packet_number = QuicPacketNumber(full_packet_number);
}
// A nonce should only present in SHLO from the server to the client when
// using QUIC crypto.
if (header->form == IETF_QUIC_LONG_HEADER_PACKET &&
header->long_packet_type == ZERO_RTT_PROTECTED &&
perspective_ == Perspective::IS_CLIENT &&
version_.handshake_protocol == PROTOCOL_QUIC_CRYPTO) {
if (!encrypted_reader->ReadBytes(
reinterpret_cast<uint8_t*>(last_nonce_.data()),
last_nonce_.size())) {
set_detailed_error("Unable to read nonce.");
RecordDroppedPacketReason(
DroppedPacketReason::INVALID_DIVERSIFICATION_NONCE);
return RaiseError(QUIC_INVALID_PACKET_HEADER);
}
header->nonce = &last_nonce_;
} else {
header->nonce = nullptr;
}
if (!visitor_->OnUnauthenticatedHeader(*header)) {
set_detailed_error(
"Visitor asked to stop processing of unauthenticated header.");
return false;
}
absl::string_view encrypted = encrypted_reader->ReadRemainingPayload();
if (!version_.HasHeaderProtection()) {
associated_data = GetAssociatedDataFromEncryptedPacket(
version_.transport_version, packet,
GetIncludedDestinationConnectionIdLength(*header),
GetIncludedSourceConnectionIdLength(*header), header->version_flag,
header->nonce != nullptr, header->packet_number_length,
header->retry_token_length_length, header->retry_token.length(),
header->length_length);
}
size_t decrypted_length = 0;
EncryptionLevel decrypted_level;
if (!DecryptPayload(packet.length(), encrypted, associated_data, *header,
decrypted_buffer, buffer_length, &decrypted_length,
&decrypted_level)) {
if (IsIetfStatelessResetPacket(*header)) {
// This is a stateless reset packet.
QuicIetfStatelessResetPacket packet(
*header, header->possible_stateless_reset_token);
visitor_->OnAuthenticatedIetfStatelessResetPacket(packet);
return true;
}
const EncryptionLevel decryption_level = GetEncryptionLevel(*header);
const bool has_decryption_key = version_.KnowsWhichDecrypterToUse() &&
decrypter_[decryption_level] != nullptr;
visitor_->OnUndecryptablePacket(
QuicEncryptedPacket(encrypted_reader->FullPayload()), decryption_level,
has_decryption_key);
set_detailed_error(absl::StrCat(
"Unable to decrypt ", EncryptionLevelToString(decryption_level),
" payload with reconstructed packet number ",
header->packet_number.ToString(), " (largest decrypted was ",
base_packet_number.ToString(), ")",
has_decryption_key || !version_.KnowsWhichDecrypterToUse()
? ""
: " (missing key)",
"."));
RecordDroppedPacketReason(DroppedPacketReason::DECRYPTION_FAILURE);
return RaiseError(QUIC_DECRYPTION_FAILURE);
}
QuicDataReader reader(decrypted_buffer, decrypted_length);
// Update the largest packet number after we have decrypted the packet
// so we are confident is not attacker controlled.
if (supports_multiple_packet_number_spaces_) {
largest_decrypted_packet_numbers_[QuicUtils::GetPacketNumberSpace(
decrypted_level)]
.UpdateMax(header->packet_number);
} else {
largest_packet_number_.UpdateMax(header->packet_number);
}
if (!visitor_->OnPacketHeader(*header)) {
RecordDroppedPacketReason(DroppedPacketReason::INVALID_PACKET_NUMBER);
// The visitor suppresses further processing of the packet.
return true;
}
if (packet.length() > kMaxIncomingPacketSize) {
set_detailed_error("Packet too large.");
return RaiseError(QUIC_PACKET_TOO_LARGE);
}
// Handle the payload.
if (VersionHasIetfQuicFrames(version_.transport_version)) {
current_received_frame_type_ = 0;
if (!ProcessIetfFrameData(&reader, *header, decrypted_level)) {
current_received_frame_type_ = 0;
QUICHE_DCHECK_NE(QUIC_NO_ERROR,
error_); // ProcessIetfFrameData sets the error.
QUICHE_DCHECK_NE("", detailed_error_);
QUIC_DLOG(WARNING) << ENDPOINT << "Unable to process frame data. Error: "
<< detailed_error_;
return false;
}
current_received_frame_type_ = 0;
} else {
if (!ProcessFrameData(&reader, *header)) {
QUICHE_DCHECK_NE(QUIC_NO_ERROR,
error_); // ProcessFrameData sets the error.
QUICHE_DCHECK_NE("", detailed_error_);
QUIC_DLOG(WARNING) << ENDPOINT << "Unable to process frame data. Error: "
<< detailed_error_;
return false;
}
}
visitor_->OnPacketComplete();
return true;
}
bool QuicFramer::ProcessDataPacket(QuicDataReader* encrypted_reader,
QuicPacketHeader* header,
const QuicEncryptedPacket& packet,
char* decrypted_buffer,
size_t buffer_length) {
if (!ProcessUnauthenticatedHeader(encrypted_reader, header)) {
QUICHE_DCHECK_NE("", detailed_error_);
QUIC_DVLOG(1)
<< ENDPOINT
<< "Unable to process packet header. Stopping parsing. Error: "
<< detailed_error_;
RecordDroppedPacketReason(DroppedPacketReason::INVALID_PACKET_NUMBER);
return false;
}
absl::string_view encrypted = encrypted_reader->ReadRemainingPayload();
absl::string_view associated_data = GetAssociatedDataFromEncryptedPacket(
version_.transport_version, packet,
GetIncludedDestinationConnectionIdLength(*header),
GetIncludedSourceConnectionIdLength(*header), header->version_flag,
header->nonce != nullptr, header->packet_number_length,
header->retry_token_length_length, header->retry_token.length(),
header->length_length);
size_t decrypted_length = 0;
EncryptionLevel decrypted_level;
if (!DecryptPayload(packet.length(), encrypted, associated_data, *header,
decrypted_buffer, buffer_length, &decrypted_length,
&decrypted_level)) {
const EncryptionLevel decryption_level = decrypter_level_;
// This version uses trial decryption so we always report to our visitor
// that we are not certain we have the correct decryption key.
const bool has_decryption_key = false;
visitor_->OnUndecryptablePacket(
QuicEncryptedPacket(encrypted_reader->FullPayload()), decryption_level,
has_decryption_key);
RecordDroppedPacketReason(DroppedPacketReason::DECRYPTION_FAILURE);
set_detailed_error(absl::StrCat("Unable to decrypt ",
EncryptionLevelToString(decryption_level),
" payload."));
return RaiseError(QUIC_DECRYPTION_FAILURE);
}
QuicDataReader reader(decrypted_buffer, decrypted_length);
// Update the largest packet number after we have decrypted the packet
// so we are confident is not attacker controlled.
if (supports_multiple_packet_number_spaces_) {
largest_decrypted_packet_numbers_[QuicUtils::GetPacketNumberSpace(
decrypted_level)]
.UpdateMax(header->packet_number);
} else {
largest_packet_number_.UpdateMax(header->packet_number);
}
if (!visitor_->OnPacketHeader(*header)) {
// The visitor suppresses further processing of the packet.
return true;
}
if (packet.length() > kMaxIncomingPacketSize) {
set_detailed_error("Packet too large.");
return RaiseError(QUIC_PACKET_TOO_LARGE);
}
// Handle the payload.
if (!ProcessFrameData(&reader, *header)) {
QUICHE_DCHECK_NE(QUIC_NO_ERROR,
error_); // ProcessFrameData sets the error.
QUICHE_DCHECK_NE("", detailed_error_);
QUIC_DLOG(WARNING) << ENDPOINT << "Unable to process frame data. Error: "
<< detailed_error_;
return false;
}
visitor_->OnPacketComplete();
return true;
}
bool QuicFramer::ProcessPublicResetPacket(QuicDataReader* reader,
const QuicPacketHeader& header) {
QuicPublicResetPacket packet(
GetServerConnectionIdAsRecipient(header, perspective_));
std::unique_ptr<CryptoHandshakeMessage> reset(
CryptoFramer::ParseMessage(reader->ReadRemainingPayload()));
if (!reset) {
set_detailed_error("Unable to read reset message.");
RecordDroppedPacketReason(DroppedPacketReason::INVALID_PUBLIC_RESET_PACKET);
return RaiseError(QUIC_INVALID_PUBLIC_RST_PACKET);
}
if (reset->tag() != kPRST) {
set_detailed_error("Incorrect message tag.");
RecordDroppedPacketReason(DroppedPacketReason::INVALID_PUBLIC_RESET_PACKET);
return RaiseError(QUIC_INVALID_PUBLIC_RST_PACKET);
}
if (reset->GetUint64(kRNON, &packet.nonce_proof) != QUIC_NO_ERROR) {
set_detailed_error("Unable to read nonce proof.");
RecordDroppedPacketReason(DroppedPacketReason::INVALID_PUBLIC_RESET_PACKET);
return RaiseError(QUIC_INVALID_PUBLIC_RST_PACKET);
}
// TODO(satyamshekhar): validate nonce to protect against DoS.
absl::string_view address;
if (reset->GetStringPiece(kCADR, &address)) {
QuicSocketAddressCoder address_coder;
if (address_coder.Decode(address.data(), address.length())) {
packet.client_address =
QuicSocketAddress(address_coder.ip(), address_coder.port());
}
}
absl::string_view endpoint_id;
if (perspective_ == Perspective::IS_CLIENT &&
reset->GetStringPiece(kEPID, &endpoint_id)) {
packet.endpoint_id = std::string(endpoint_id);
packet.endpoint_id += '\0';
}
visitor_->OnPublicResetPacket(packet);
return true;
}
bool QuicFramer::IsIetfStatelessResetPacket(
const QuicPacketHeader& header) const {
QUIC_BUG_IF(quic_bug_12975_3, header.has_possible_stateless_reset_token &&
perspective_ != Perspective::IS_CLIENT)
<< "has_possible_stateless_reset_token can only be true at client side.";
return header.form == IETF_QUIC_SHORT_HEADER_PACKET &&
header.has_possible_stateless_reset_token &&
visitor_->IsValidStatelessResetToken(
header.possible_stateless_reset_token);
}
bool QuicFramer::HasEncrypterOfEncryptionLevel(EncryptionLevel level) const {
return encrypter_[level] != nullptr;
}
bool QuicFramer::HasDecrypterOfEncryptionLevel(EncryptionLevel level) const {
return decrypter_[level] != nullptr;
}
bool QuicFramer::HasAnEncrypterForSpace(PacketNumberSpace space) const {
switch (space) {
case INITIAL_DATA:
return HasEncrypterOfEncryptionLevel(ENCRYPTION_INITIAL);
case HANDSHAKE_DATA:
return HasEncrypterOfEncryptionLevel(ENCRYPTION_HANDSHAKE);
case APPLICATION_DATA:
return HasEncrypterOfEncryptionLevel(ENCRYPTION_ZERO_RTT) ||
HasEncrypterOfEncryptionLevel(ENCRYPTION_FORWARD_SECURE);
case NUM_PACKET_NUMBER_SPACES:
break;
}
QUIC_BUG(quic_bug_10850_55)
<< ENDPOINT
<< "Try to send data of space: " << PacketNumberSpaceToString(space);
return false;
}
EncryptionLevel QuicFramer::GetEncryptionLevelToSendApplicationData() const {
if (!HasAnEncrypterForSpace(APPLICATION_DATA)) {
QUIC_BUG(quic_bug_12975_4)
<< "Tried to get encryption level to send application data with no "
"encrypter available.";
return NUM_ENCRYPTION_LEVELS;
}
if (HasEncrypterOfEncryptionLevel(ENCRYPTION_FORWARD_SECURE)) {
return ENCRYPTION_FORWARD_SECURE;
}
QUICHE_DCHECK(HasEncrypterOfEncryptionLevel(ENCRYPTION_ZERO_RTT));
return ENCRYPTION_ZERO_RTT;
}
bool QuicFramer::AppendPacketHeader(const QuicPacketHeader& header,
QuicDataWriter* writer,
size_t* length_field_offset) {
if (version().HasIetfInvariantHeader()) {
return AppendIetfPacketHeader(header, writer, length_field_offset);
}
QUIC_DVLOG(1) << ENDPOINT << "Appending header: " << header;
uint8_t public_flags = 0;
if (header.reset_flag) {
public_flags |= PACKET_PUBLIC_FLAGS_RST;
}
if (header.version_flag) {
public_flags |= PACKET_PUBLIC_FLAGS_VERSION;
}
public_flags |= GetPacketNumberFlags(header.packet_number_length)
<< kPublicHeaderSequenceNumberShift;
if (header.nonce != nullptr) {
QUICHE_DCHECK_EQ(Perspective::IS_SERVER, perspective_);
public_flags |= PACKET_PUBLIC_FLAGS_NONCE;
}
QuicConnectionId server_connection_id =
GetServerConnectionIdAsSender(header, perspective_);
QuicConnectionIdIncluded server_connection_id_included =
GetServerConnectionIdIncludedAsSender(header, perspective_);
QUICHE_DCHECK_EQ(CONNECTION_ID_ABSENT,
GetClientConnectionIdIncludedAsSender(header, perspective_))
<< ENDPOINT << ParsedQuicVersionToString(version_)
<< " invalid header: " << header;
switch (server_connection_id_included) {
case CONNECTION_ID_ABSENT:
if (!writer->WriteUInt8(public_flags |
PACKET_PUBLIC_FLAGS_0BYTE_CONNECTION_ID)) {
return false;
}
break;
case CONNECTION_ID_PRESENT:
QUIC_BUG_IF(quic_bug_12975_5,
!QuicUtils::IsConnectionIdValidForVersion(
server_connection_id, transport_version()))
<< "AppendPacketHeader: attempted to use connection ID "
<< server_connection_id << " which is invalid with version "
<< version();
public_flags |= PACKET_PUBLIC_FLAGS_8BYTE_CONNECTION_ID;
if (perspective_ == Perspective::IS_CLIENT) {
public_flags |= PACKET_PUBLIC_FLAGS_8BYTE_CONNECTION_ID_OLD;
}
if (!writer->WriteUInt8(public_flags) ||
!writer->WriteConnectionId(server_connection_id)) {
return false;
}
break;
}
last_serialized_server_connection_id_ = server_connection_id;
if (header.version_flag) {
QUICHE_DCHECK_EQ(Perspective::IS_CLIENT, perspective_);
QuicVersionLabel version_label = CreateQuicVersionLabel(version_);
if (!writer->WriteUInt32(version_label)) {
return false;
}
QUIC_DVLOG(1) << ENDPOINT << "label = '"
<< QuicVersionLabelToString(version_label) << "'";
}
if (header.nonce != nullptr &&
!writer->WriteBytes(header.nonce, kDiversificationNonceSize)) {
return false;
}
if (!AppendPacketNumber(header.packet_number_length, header.packet_number,
writer)) {
return false;
}
return true;
}
bool QuicFramer::AppendIetfHeaderTypeByte(const QuicPacketHeader& header,
QuicDataWriter* writer) {
uint8_t type = 0;
if (header.version_flag) {
type = static_cast<uint8_t>(
FLAGS_LONG_HEADER | FLAGS_FIXED_BIT |
LongHeaderTypeToOnWireValue(header.long_packet_type) |
PacketNumberLengthToOnWireValue(header.packet_number_length));
} else {
type = static_cast<uint8_t>(
FLAGS_FIXED_BIT | (current_key_phase_bit_ ? FLAGS_KEY_PHASE_BIT : 0) |
PacketNumberLengthToOnWireValue(header.packet_number_length));
}
return writer->WriteUInt8(type);
}
bool QuicFramer::AppendIetfPacketHeader(const QuicPacketHeader& header,
QuicDataWriter* writer,
size_t* length_field_offset) {
QUIC_DVLOG(1) << ENDPOINT << "Appending IETF header: " << header;
QuicConnectionId server_connection_id =
GetServerConnectionIdAsSender(header, perspective_);
QUIC_BUG_IF(quic_bug_12975_6, !QuicUtils::IsConnectionIdValidForVersion(
server_connection_id, transport_version()))
<< "AppendIetfPacketHeader: attempted to use connection ID "
<< server_connection_id << " which is invalid with version " << version();
if (!AppendIetfHeaderTypeByte(header, writer)) {
return false;
}
if (header.version_flag) {
QUICHE_DCHECK_NE(VERSION_NEGOTIATION, header.long_packet_type)
<< "QuicFramer::AppendIetfPacketHeader does not support sending "
"version negotiation packets, use "
"QuicFramer::BuildVersionNegotiationPacket instead "
<< header;
// Append version for long header.
QuicVersionLabel version_label = CreateQuicVersionLabel(version_);
if (!writer->WriteUInt32(version_label)) {
return false;
}
}
// Append connection ID.
if (!AppendIetfConnectionIds(
header.version_flag, version_.HasLengthPrefixedConnectionIds(),
header.destination_connection_id_included != CONNECTION_ID_ABSENT
? header.destination_connection_id
: EmptyQuicConnectionId(),
header.source_connection_id_included != CONNECTION_ID_ABSENT
? header.source_connection_id
: EmptyQuicConnectionId(),
writer)) {
return false;
}
last_serialized_server_connection_id_ = server_connection_id;
if (version_.SupportsClientConnectionIds()) {
last_serialized_client_connection_id_ =
GetClientConnectionIdAsSender(header, perspective_);
}
// TODO(b/141924462) Remove this QUIC_BUG once we do support sending RETRY.
QUIC_BUG_IF(quic_bug_12975_7,
header.version_flag && header.long_packet_type == RETRY)
<< "Sending IETF RETRY packets is not currently supported " << header;
if (QuicVersionHasLongHeaderLengths(transport_version()) &&
header.version_flag) {
if (header.long_packet_type == INITIAL) {
QUICHE_DCHECK_NE(VARIABLE_LENGTH_INTEGER_LENGTH_0,
header.retry_token_length_length)
<< ENDPOINT << ParsedQuicVersionToString(version_)
<< " bad retry token length length in header: " << header;
// Write retry token length.
if (!writer->WriteVarInt62(header.retry_token.length(),
header.retry_token_length_length)) {
return false;
}
// Write retry token.
if (!header.retry_token.empty() &&
!writer->WriteStringPiece(header.retry_token)) {
return false;
}
}
if (length_field_offset != nullptr) {
*length_field_offset = writer->length();
}
// Add fake length to reserve two bytes to add length in later.
writer->WriteVarInt62(256);
} else if (length_field_offset != nullptr) {
*length_field_offset = 0;
}
// Append packet number.
if (!AppendPacketNumber(header.packet_number_length, header.packet_number,
writer)) {
return false;
}
last_written_packet_number_length_ = header.packet_number_length;
if (!header.version_flag) {
return true;
}
if (header.nonce != nullptr) {
QUICHE_DCHECK(header.version_flag);
QUICHE_DCHECK_EQ(ZERO_RTT_PROTECTED, header.long_packet_type);
QUICHE_DCHECK_EQ(Perspective::IS_SERVER, perspective_);
if (!writer->WriteBytes(header.nonce, kDiversificationNonceSize)) {
return false;
}
}
return true;
}
const QuicTime::Delta QuicFramer::CalculateTimestampFromWire(
uint32_t time_delta_us) {
// The new time_delta might have wrapped to the next epoch, or it
// might have reverse wrapped to the previous epoch, or it might
// remain in the same epoch. Select the time closest to the previous
// time.
//
// epoch_delta is the delta between epochs. A delta is 4 bytes of
// microseconds.
const uint64_t epoch_delta = UINT64_C(1) << 32;
uint64_t epoch = last_timestamp_.ToMicroseconds() & ~(epoch_delta - 1);
// Wrapping is safe here because a wrapped value will not be ClosestTo below.
uint64_t prev_epoch = epoch - epoch_delta;
uint64_t next_epoch = epoch + epoch_delta;
uint64_t time = ClosestTo(
last_timestamp_.ToMicroseconds(), epoch + time_delta_us,
ClosestTo(last_timestamp_.ToMicroseconds(), prev_epoch + time_delta_us,
next_epoch + time_delta_us));
return QuicTime::Delta::FromMicroseconds(time);
}
uint64_t QuicFramer::CalculatePacketNumberFromWire(
QuicPacketNumberLength packet_number_length,
QuicPacketNumber base_packet_number,
uint64_t packet_number) const {
// The new packet number might have wrapped to the next epoch, or
// it might have reverse wrapped to the previous epoch, or it might
// remain in the same epoch. Select the packet number closest to the
// next expected packet number, the previous packet number plus 1.
// epoch_delta is the delta between epochs the packet number was serialized
// with, so the correct value is likely the same epoch as the last sequence
// number or an adjacent epoch.
if (!base_packet_number.IsInitialized()) {
return packet_number;
}
const uint64_t epoch_delta = UINT64_C(1) << (8 * packet_number_length);
uint64_t next_packet_number = base_packet_number.ToUint64() + 1;
uint64_t epoch = base_packet_number.ToUint64() & ~(epoch_delta - 1);
uint64_t prev_epoch = epoch - epoch_delta;
uint64_t next_epoch = epoch + epoch_delta;
return ClosestTo(next_packet_number, epoch + packet_number,
ClosestTo(next_packet_number, prev_epoch + packet_number,
next_epoch + packet_number));
}
bool QuicFramer::ProcessPublicHeader(QuicDataReader* reader,
bool packet_has_ietf_packet_header,
QuicPacketHeader* header) {
if (packet_has_ietf_packet_header) {
return ProcessIetfPacketHeader(reader, header);
}
uint8_t public_flags;
if (!reader->ReadBytes(&public_flags, 1)) {
set_detailed_error("Unable to read public flags.");
return false;
}
header->reset_flag = (public_flags & PACKET_PUBLIC_FLAGS_RST) != 0;
header->version_flag = (public_flags & PACKET_PUBLIC_FLAGS_VERSION) != 0;
if (validate_flags_ && !header->version_flag &&
public_flags > PACKET_PUBLIC_FLAGS_MAX) {
set_detailed_error("Illegal public flags value.");
return false;
}
if (header->reset_flag && header->version_flag) {
set_detailed_error("Got version flag in reset packet");
return false;
}
QuicConnectionId* header_connection_id = &header->destination_connection_id;
QuicConnectionIdIncluded* header_connection_id_included =
&header->destination_connection_id_included;
if (perspective_ == Perspective::IS_CLIENT) {
header_connection_id = &header->source_connection_id;
header_connection_id_included = &header->source_connection_id_included;
}
switch (public_flags & PACKET_PUBLIC_FLAGS_8BYTE_CONNECTION_ID) {
case PACKET_PUBLIC_FLAGS_8BYTE_CONNECTION_ID:
if (!reader->ReadConnectionId(header_connection_id,
kQuicDefaultConnectionIdLength)) {
set_detailed_error("Unable to read ConnectionId.");
return false;
}
*header_connection_id_included = CONNECTION_ID_PRESENT;
break;
case PACKET_PUBLIC_FLAGS_0BYTE_CONNECTION_ID:
*header_connection_id_included = CONNECTION_ID_ABSENT;
*header_connection_id = last_serialized_server_connection_id_;
break;
}
header->packet_number_length = ReadSequenceNumberLength(
public_flags >> kPublicHeaderSequenceNumberShift);
// Read the version only if the packet is from the client.
// version flag from the server means version negotiation packet.
if (header->version_flag && perspective_ == Perspective::IS_SERVER) {
QuicVersionLabel version_label;
if (!ProcessVersionLabel(reader, &version_label)) {
set_detailed_error("Unable to read protocol version.");
return false;
}
// If the version from the new packet is the same as the version of this
// framer, then the public flags should be set to something we understand.
// If not, this raises an error.
ParsedQuicVersion version = ParseQuicVersionLabel(version_label);
if (version == version_ && public_flags > PACKET_PUBLIC_FLAGS_MAX) {
set_detailed_error("Illegal public flags value.");
return false;
}
header->version = version;
}
// A nonce should only be present in packets from the server to the client,
// which are neither version negotiation nor public reset packets.
if (public_flags & PACKET_PUBLIC_FLAGS_NONCE &&
!(public_flags & PACKET_PUBLIC_FLAGS_VERSION) &&
!(public_flags & PACKET_PUBLIC_FLAGS_RST) &&
// The nonce flag from a client is ignored and is assumed to be an older
// client indicating an eight-byte connection ID.
perspective_ == Perspective::IS_CLIENT) {
if (!reader->ReadBytes(reinterpret_cast<uint8_t*>(last_nonce_.data()),
last_nonce_.size())) {
set_detailed_error("Unable to read nonce.");
return false;
}
header->nonce = &last_nonce_;
} else {
header->nonce = nullptr;
}
return true;
}
// static
QuicPacketNumberLength QuicFramer::GetMinPacketNumberLength(
QuicPacketNumber packet_number) {
QUICHE_DCHECK(packet_number.IsInitialized());
if (packet_number < QuicPacketNumber(1 << (PACKET_1BYTE_PACKET_NUMBER * 8))) {
return PACKET_1BYTE_PACKET_NUMBER;
} else if (packet_number <
QuicPacketNumber(1 << (PACKET_2BYTE_PACKET_NUMBER * 8))) {
return PACKET_2BYTE_PACKET_NUMBER;
} else if (packet_number <
QuicPacketNumber(UINT64_C(1)
<< (PACKET_4BYTE_PACKET_NUMBER * 8))) {
return PACKET_4BYTE_PACKET_NUMBER;
} else {
return PACKET_6BYTE_PACKET_NUMBER;
}
}
// static
uint8_t QuicFramer::GetPacketNumberFlags(
QuicPacketNumberLength packet_number_length) {
switch (packet_number_length) {
case PACKET_1BYTE_PACKET_NUMBER:
return PACKET_FLAGS_1BYTE_PACKET;
case PACKET_2BYTE_PACKET_NUMBER:
return PACKET_FLAGS_2BYTE_PACKET;
case PACKET_4BYTE_PACKET_NUMBER:
return PACKET_FLAGS_4BYTE_PACKET;
case PACKET_6BYTE_PACKET_NUMBER:
case PACKET_8BYTE_PACKET_NUMBER:
return PACKET_FLAGS_8BYTE_PACKET;
default:
QUIC_BUG(quic_bug_10850_56) << "Unreachable case statement.";
return PACKET_FLAGS_8BYTE_PACKET;
}
}
// static
QuicFramer::AckFrameInfo QuicFramer::GetAckFrameInfo(
const QuicAckFrame& frame) {
AckFrameInfo new_ack_info;
if (frame.packets.Empty()) {
return new_ack_info;
}
// The first block is the last interval. It isn't encoded with the gap-length
// encoding, so skip it.
new_ack_info.first_block_length = frame.packets.LastIntervalLength();
auto itr = frame.packets.rbegin();
QuicPacketNumber previous_start = itr->min();
new_ack_info.max_block_length = itr->Length();
++itr;
// Don't do any more work after getting information for 256 ACK blocks; any
// more can't be encoded anyway.
for (; itr != frame.packets.rend() &&
new_ack_info.num_ack_blocks < std::numeric_limits<uint8_t>::max();
previous_start = itr->min(), ++itr) {
const auto& interval = *itr;
const QuicPacketCount total_gap = previous_start - interval.max();
new_ack_info.num_ack_blocks +=
(total_gap + std::numeric_limits<uint8_t>::max() - 1) /
std::numeric_limits<uint8_t>::max();
new_ack_info.max_block_length =
std::max(new_ack_info.max_block_length, interval.Length());
}
return new_ack_info;
}
bool QuicFramer::ProcessUnauthenticatedHeader(QuicDataReader* encrypted_reader,
QuicPacketHeader* header) {
QuicPacketNumber base_packet_number;
if (supports_multiple_packet_number_spaces_) {
PacketNumberSpace pn_space = GetPacketNumberSpace(*header);
if (pn_space == NUM_PACKET_NUMBER_SPACES) {
set_detailed_error("Unable to determine packet number space.");
return RaiseError(QUIC_INVALID_PACKET_HEADER);
}
base_packet_number = largest_decrypted_packet_numbers_[pn_space];
} else {
base_packet_number = largest_packet_number_;
}
uint64_t full_packet_number;
if (!ProcessAndCalculatePacketNumber(
encrypted_reader, header->packet_number_length, base_packet_number,
&full_packet_number)) {
set_detailed_error("Unable to read packet number.");
return RaiseError(QUIC_INVALID_PACKET_HEADER);
}
if (!IsValidFullPacketNumber(full_packet_number, version())) {
set_detailed_error("packet numbers cannot be 0.");
return RaiseError(QUIC_INVALID_PACKET_HEADER);
}
header->packet_number = QuicPacketNumber(full_packet_number);
if (!visitor_->OnUnauthenticatedHeader(*header)) {
set_detailed_error(
"Visitor asked to stop processing of unauthenticated header.");
return false;
}
// The function we are in is called because the framer believes that it is
// processing a packet that uses the non-IETF (i.e. Google QUIC) packet header
// type. Usually, the framer makes that decision based on the framer's
// version, but when the framer is used with Perspective::IS_SERVER, then
// before version negotiation is complete (specifically, before
// InferPacketHeaderTypeFromVersion is called), this decision is made based on
// the type byte of the packet.
//
// If the framer's version KnowsWhichDecrypterToUse, then that version expects
// to use the IETF packet header type. If that's the case and we're in this
// function, then the packet received is invalid: the framer was expecting an
// IETF packet header and didn't get one.
if (version().KnowsWhichDecrypterToUse()) {
set_detailed_error("Invalid public header type for expected version.");
return RaiseError(QUIC_INVALID_PACKET_HEADER);
}
return true;
}
bool QuicFramer::ProcessIetfHeaderTypeByte(QuicDataReader* reader,
QuicPacketHeader* header) {
uint8_t type;
if (!reader->ReadBytes(&type, 1)) {
set_detailed_error("Unable to read first byte.");
return false;
}
header->type_byte = type;
// Determine whether this is a long or short header.
header->form = GetIetfPacketHeaderFormat(type);
if (header->form == IETF_QUIC_LONG_HEADER_PACKET) {
// Version is always present in long headers.
header->version_flag = true;
// In versions that do not support client connection IDs, we mark the
// corresponding connection ID as absent.
header->destination_connection_id_included =
(perspective_ == Perspective::IS_SERVER ||
version_.SupportsClientConnectionIds())
? CONNECTION_ID_PRESENT
: CONNECTION_ID_ABSENT;
header->source_connection_id_included =
(perspective_ == Perspective::IS_CLIENT ||
version_.SupportsClientConnectionIds())
? CONNECTION_ID_PRESENT
: CONNECTION_ID_ABSENT;
// Read version tag.
QuicVersionLabel version_label;
if (!ProcessVersionLabel(reader, &version_label)) {
set_detailed_error("Unable to read protocol version.");
return false;
}
if (!version_label) {
// Version label is 0 indicating this is a version negotiation packet.
header->long_packet_type = VERSION_NEGOTIATION;
} else {
header->version = ParseQuicVersionLabel(version_label);
if (header->version.IsKnown()) {
if (!(type & FLAGS_FIXED_BIT)) {
set_detailed_error("Fixed bit is 0 in long header.");
return false;
}
if (!GetLongHeaderType(type, &header->long_packet_type)) {
set_detailed_error("Illegal long header type value.");
return false;
}
if (header->long_packet_type == RETRY) {
if (!version().SupportsRetry()) {
set_detailed_error("RETRY not supported in this version.");
return false;
}
if (perspective_ == Perspective::IS_SERVER) {
set_detailed_error("Client-initiated RETRY is invalid.");
return false;
}
} else if (!header->version.HasHeaderProtection()) {
header->packet_number_length = GetLongHeaderPacketNumberLength(type);
}
}
}
QUIC_DVLOG(1) << ENDPOINT << "Received IETF long header: "
<< QuicUtils::QuicLongHeaderTypetoString(
header->long_packet_type);
return true;
}
QUIC_DVLOG(1) << ENDPOINT << "Received IETF short header";
// Version is not present in short headers.
header->version_flag = false;
// In versions that do not support client connection IDs, the client will not
// receive destination connection IDs.
header->destination_connection_id_included =
(perspective_ == Perspective::IS_SERVER ||
version_.SupportsClientConnectionIds())
? CONNECTION_ID_PRESENT
: CONNECTION_ID_ABSENT;
header->source_connection_id_included = CONNECTION_ID_ABSENT;
if (!(type & FLAGS_FIXED_BIT)) {
set_detailed_error("Fixed bit is 0 in short header.");
return false;
}
if (!version_.HasHeaderProtection()) {
header->packet_number_length = GetShortHeaderPacketNumberLength(type);
}
QUIC_DVLOG(1) << "packet_number_length = " << header->packet_number_length;
return true;
}
// static
bool QuicFramer::ProcessVersionLabel(QuicDataReader* reader,
QuicVersionLabel* version_label) {
if (!reader->ReadUInt32(version_label)) {
return false;
}
return true;
}
// static
bool QuicFramer::ProcessAndValidateIetfConnectionIdLength(
QuicDataReader* reader,
ParsedQuicVersion version,
Perspective perspective,
bool should_update_expected_server_connection_id_length,
uint8_t* expected_server_connection_id_length,
uint8_t* destination_connection_id_length,
uint8_t* source_connection_id_length,
std::string* detailed_error) {
uint8_t connection_id_lengths_byte;
if (!reader->ReadBytes(&connection_id_lengths_byte, 1)) {
*detailed_error = "Unable to read ConnectionId length.";
return false;
}
uint8_t dcil =
(connection_id_lengths_byte & kDestinationConnectionIdLengthMask) >> 4;
if (dcil != 0) {
dcil += kConnectionIdLengthAdjustment;
}
uint8_t scil = connection_id_lengths_byte & kSourceConnectionIdLengthMask;
if (scil != 0) {
scil += kConnectionIdLengthAdjustment;
}
if (should_update_expected_server_connection_id_length) {
uint8_t server_connection_id_length =
perspective == Perspective::IS_SERVER ? dcil : scil;
if (*expected_server_connection_id_length != server_connection_id_length) {
QUIC_DVLOG(1) << "Updating expected_server_connection_id_length: "
<< static_cast<int>(*expected_server_connection_id_length)
<< " -> " << static_cast<int>(server_connection_id_length);
*expected_server_connection_id_length = server_connection_id_length;
}
}
if (!should_update_expected_server_connection_id_length &&
(dcil != *destination_connection_id_length ||
scil != *source_connection_id_length) &&
version.IsKnown() && !version.AllowsVariableLengthConnectionIds()) {
QUIC_DVLOG(1) << "dcil: " << static_cast<uint32_t>(dcil)
<< ", scil: " << static_cast<uint32_t>(scil);
*detailed_error = "Invalid ConnectionId length.";
return false;
}
*destination_connection_id_length = dcil;
*source_connection_id_length = scil;
return true;
}
bool QuicFramer::ValidateReceivedConnectionIds(const QuicPacketHeader& header) {
bool skip_server_connection_id_validation =
perspective_ == Perspective::IS_CLIENT &&
header.form == IETF_QUIC_SHORT_HEADER_PACKET;
if (!skip_server_connection_id_validation &&
!QuicUtils::IsConnectionIdValidForVersion(
GetServerConnectionIdAsRecipient(header, perspective_),
transport_version())) {
set_detailed_error("Received server connection ID with invalid length.");
return false;
}
bool skip_client_connection_id_validation =
perspective_ == Perspective::IS_SERVER &&
header.form == IETF_QUIC_SHORT_HEADER_PACKET;
if (!skip_client_connection_id_validation &&
version_.SupportsClientConnectionIds() &&
!QuicUtils::IsConnectionIdValidForVersion(
GetClientConnectionIdAsRecipient(header, perspective_),
transport_version())) {
set_detailed_error("Received client connection ID with invalid length.");
return false;
}
return true;
}
bool QuicFramer::ProcessIetfPacketHeader(QuicDataReader* reader,
QuicPacketHeader* header) {
if (version_.HasLengthPrefixedConnectionIds()) {
uint8_t expected_destination_connection_id_length =
perspective_ == Perspective::IS_CLIENT
? expected_client_connection_id_length_
: expected_server_connection_id_length_;
QuicVersionLabel version_label;
bool has_length_prefix;
std::string detailed_error;
QuicErrorCode parse_result = QuicFramer::ParsePublicHeader(
reader, expected_destination_connection_id_length,
version_.HasIetfInvariantHeader(), &header->type_byte, &header->form,
&header->version_flag, &has_length_prefix, &version_label,
&header->version, &header->destination_connection_id,
&header->source_connection_id, &header->long_packet_type,
&header->retry_token_length_length, &header->retry_token,
&detailed_error);
if (parse_result != QUIC_NO_ERROR) {
set_detailed_error(detailed_error);
return false;
}
header->destination_connection_id_included = CONNECTION_ID_PRESENT;
header->source_connection_id_included =
header->version_flag ? CONNECTION_ID_PRESENT : CONNECTION_ID_ABSENT;
if (!ValidateReceivedConnectionIds(*header)) {
return false;
}
if (header->version_flag &&
header->long_packet_type != VERSION_NEGOTIATION &&
!(header->type_byte & FLAGS_FIXED_BIT)) {
set_detailed_error("Fixed bit is 0 in long header.");
return false;
}
if (!header->version_flag && !(header->type_byte & FLAGS_FIXED_BIT)) {
set_detailed_error("Fixed bit is 0 in short header.");
return false;
}
if (!header->version_flag) {
if (!version_.HasHeaderProtection()) {
header->packet_number_length =
GetShortHeaderPacketNumberLength(header->type_byte);
}
return true;
}
if (header->long_packet_type == RETRY) {
if (!version().SupportsRetry()) {
set_detailed_error("RETRY not supported in this version.");
return false;
}
if (perspective_ == Perspective::IS_SERVER) {
set_detailed_error("Client-initiated RETRY is invalid.");
return false;
}
return true;
}
if (header->version.IsKnown() && !header->version.HasHeaderProtection()) {
header->packet_number_length =
GetLongHeaderPacketNumberLength(header->type_byte);
}
return true;
}
if (!ProcessIetfHeaderTypeByte(reader, header)) {
return false;
}
uint8_t destination_connection_id_length =
header->destination_connection_id_included == CONNECTION_ID_PRESENT
? (perspective_ == Perspective::IS_SERVER
? expected_server_connection_id_length_
: expected_client_connection_id_length_)
: 0;
uint8_t source_connection_id_length =
header->source_connection_id_included == CONNECTION_ID_PRESENT
? (perspective_ == Perspective::IS_CLIENT
? expected_server_connection_id_length_
: expected_client_connection_id_length_)
: 0;
if (header->form == IETF_QUIC_LONG_HEADER_PACKET) {
if (!ProcessAndValidateIetfConnectionIdLength(
reader, header->version, perspective_,
/*should_update_expected_server_connection_id_length=*/false,
&expected_server_connection_id_length_,
&destination_connection_id_length, &source_connection_id_length,
&detailed_error_)) {
return false;
}
}
// Read connection ID.
if (!reader->ReadConnectionId(&header->destination_connection_id,
destination_connection_id_length)) {
set_detailed_error("Unable to read destination connection ID.");
return false;
}
if (!reader->ReadConnectionId(&header->source_connection_id,
source_connection_id_length)) {
set_detailed_error("Unable to read source connection ID.");
return false;
}
if (header->source_connection_id_included == CONNECTION_ID_ABSENT) {
if (!header->source_connection_id.IsEmpty()) {
QUICHE_DCHECK(!version_.SupportsClientConnectionIds());
set_detailed_error("Client connection ID not supported in this version.");
return false;
}
}
return ValidateReceivedConnectionIds(*header);
}
bool QuicFramer::ProcessAndCalculatePacketNumber(
QuicDataReader* reader,
QuicPacketNumberLength packet_number_length,
QuicPacketNumber base_packet_number,
uint64_t* packet_number) {
uint64_t wire_packet_number;
if (!reader->ReadBytesToUInt64(packet_number_length, &wire_packet_number)) {
return false;
}
// TODO(ianswett): Explore the usefulness of trying multiple packet numbers
// in case the first guess is incorrect.
*packet_number = CalculatePacketNumberFromWire(
packet_number_length, base_packet_number, wire_packet_number);
return true;
}
bool QuicFramer::ProcessFrameData(QuicDataReader* reader,
const QuicPacketHeader& header) {
QUICHE_DCHECK(!VersionHasIetfQuicFrames(version_.transport_version))
<< "IETF QUIC Framing negotiated but attempting to process frames as "
"non-IETF QUIC.";
if (reader->IsDoneReading()) {
set_detailed_error("Packet has no frames.");
return RaiseError(QUIC_MISSING_PAYLOAD);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing packet with header " << header;
while (!reader->IsDoneReading()) {
uint8_t frame_type;
if (!reader->ReadBytes(&frame_type, 1)) {
set_detailed_error("Unable to read frame type.");
return RaiseError(QUIC_INVALID_FRAME_DATA);
}
const uint8_t special_mask = version_.HasIetfInvariantHeader()
? kQuicFrameTypeSpecialMask
: kQuicFrameTypeBrokenMask;
if (frame_type & special_mask) {
// Stream Frame
if (frame_type & kQuicFrameTypeStreamMask) {
QuicStreamFrame frame;
if (!ProcessStreamFrame(reader, frame_type, &frame)) {
return RaiseError(QUIC_INVALID_STREAM_DATA);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing stream frame " << frame;
if (!visitor_->OnStreamFrame(frame)) {
QUIC_DVLOG(1) << ENDPOINT
<< "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
continue;
}
// Ack Frame
if (frame_type & kQuicFrameTypeAckMask) {
if (!ProcessAckFrame(reader, frame_type)) {
return RaiseError(QUIC_INVALID_ACK_DATA);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing ACK frame";
continue;
}
// This was a special frame type that did not match any
// of the known ones. Error.
set_detailed_error("Illegal frame type.");
QUIC_DLOG(WARNING) << ENDPOINT << "Illegal frame type: "
<< static_cast<int>(frame_type);
return RaiseError(QUIC_INVALID_FRAME_DATA);
}
switch (frame_type) {
case PADDING_FRAME: {
QuicPaddingFrame frame;
ProcessPaddingFrame(reader, &frame);
QUIC_DVLOG(2) << ENDPOINT << "Processing padding frame " << frame;
if (!visitor_->OnPaddingFrame(frame)) {
QUIC_DVLOG(1) << "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
continue;
}
case RST_STREAM_FRAME: {
QuicRstStreamFrame frame;
if (!ProcessRstStreamFrame(reader, &frame)) {
return RaiseError(QUIC_INVALID_RST_STREAM_DATA);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing reset stream frame " << frame;
if (!visitor_->OnRstStreamFrame(frame)) {
QUIC_DVLOG(1) << "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
continue;
}
case CONNECTION_CLOSE_FRAME: {
QuicConnectionCloseFrame frame;
if (!ProcessConnectionCloseFrame(reader, &frame)) {
return RaiseError(QUIC_INVALID_CONNECTION_CLOSE_DATA);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing connection close frame "
<< frame;
if (!visitor_->OnConnectionCloseFrame(frame)) {
QUIC_DVLOG(1) << ENDPOINT
<< "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
continue;
}
case GOAWAY_FRAME: {
QuicGoAwayFrame goaway_frame;
if (!ProcessGoAwayFrame(reader, &goaway_frame)) {
return RaiseError(QUIC_INVALID_GOAWAY_DATA);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing go away frame "
<< goaway_frame;
if (!visitor_->OnGoAwayFrame(goaway_frame)) {
QUIC_DVLOG(1) << ENDPOINT
<< "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
continue;
}
case WINDOW_UPDATE_FRAME: {
QuicWindowUpdateFrame window_update_frame;
if (!ProcessWindowUpdateFrame(reader, &window_update_frame)) {
return RaiseError(QUIC_INVALID_WINDOW_UPDATE_DATA);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing window update frame "
<< window_update_frame;
if (!visitor_->OnWindowUpdateFrame(window_update_frame)) {
QUIC_DVLOG(1) << ENDPOINT
<< "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
continue;
}
case BLOCKED_FRAME: {
QuicBlockedFrame blocked_frame;
if (!ProcessBlockedFrame(reader, &blocked_frame)) {
return RaiseError(QUIC_INVALID_BLOCKED_DATA);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing blocked frame "
<< blocked_frame;
if (!visitor_->OnBlockedFrame(blocked_frame)) {
QUIC_DVLOG(1) << ENDPOINT
<< "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
continue;
}
case STOP_WAITING_FRAME: {
QuicStopWaitingFrame stop_waiting_frame;
if (!ProcessStopWaitingFrame(reader, header, &stop_waiting_frame)) {
return RaiseError(QUIC_INVALID_STOP_WAITING_DATA);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing stop waiting frame "
<< stop_waiting_frame;
if (!visitor_->OnStopWaitingFrame(stop_waiting_frame)) {
QUIC_DVLOG(1) << ENDPOINT
<< "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
continue;
}
case PING_FRAME: {
// Ping has no payload.
QuicPingFrame ping_frame;
if (!visitor_->OnPingFrame(ping_frame)) {
QUIC_DVLOG(1) << ENDPOINT
<< "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
QUIC_DVLOG(2) << ENDPOINT << "Processing ping frame " << ping_frame;
continue;
}
case IETF_EXTENSION_MESSAGE_NO_LENGTH:
ABSL_FALLTHROUGH_INTENDED;
case IETF_EXTENSION_MESSAGE: {
QuicMessageFrame message_frame;
if (!ProcessMessageFrame(reader,
frame_type == IETF_EXTENSION_MESSAGE_NO_LENGTH,
&message_frame)) {
return RaiseError(QUIC_INVALID_MESSAGE_DATA);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing message frame "
<< message_frame;
if (!visitor_->OnMessageFrame(message_frame)) {
QUIC_DVLOG(1) << ENDPOINT
<< "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
break;
}
case CRYPTO_FRAME: {
if (!QuicVersionUsesCryptoFrames(version_.transport_version)) {
set_detailed_error("Illegal frame type.");
return RaiseError(QUIC_INVALID_FRAME_DATA);
}
QuicCryptoFrame frame;
if (!ProcessCryptoFrame(reader, GetEncryptionLevel(header), &frame)) {
return RaiseError(QUIC_INVALID_FRAME_DATA);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing crypto frame " << frame;
if (!visitor_->OnCryptoFrame(frame)) {
QUIC_DVLOG(1) << "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
break;
}
case HANDSHAKE_DONE_FRAME: {
// HANDSHAKE_DONE has no payload.
QuicHandshakeDoneFrame handshake_done_frame;
QUIC_DVLOG(2) << ENDPOINT << "Processing handshake done frame "
<< handshake_done_frame;
if (!visitor_->OnHandshakeDoneFrame(handshake_done_frame)) {
QUIC_DVLOG(1) << ENDPOINT
<< "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
break;
}
default:
set_detailed_error("Illegal frame type.");
QUIC_DLOG(WARNING) << ENDPOINT << "Illegal frame type: "
<< static_cast<int>(frame_type);
return RaiseError(QUIC_INVALID_FRAME_DATA);
}
}
return true;
}
// static
bool QuicFramer::IsIetfFrameTypeExpectedForEncryptionLevel(
uint64_t frame_type,
EncryptionLevel level) {
switch (level) {
case ENCRYPTION_INITIAL:
case ENCRYPTION_HANDSHAKE:
return frame_type == IETF_CRYPTO || frame_type == IETF_ACK ||
frame_type == IETF_PING || frame_type == IETF_PADDING ||
frame_type == IETF_CONNECTION_CLOSE;
case ENCRYPTION_ZERO_RTT:
return !(frame_type == IETF_ACK || frame_type == IETF_CRYPTO ||
frame_type == IETF_HANDSHAKE_DONE ||
frame_type == IETF_NEW_TOKEN ||
frame_type == IETF_PATH_RESPONSE ||
frame_type == IETF_RETIRE_CONNECTION_ID);
case ENCRYPTION_FORWARD_SECURE:
return true;
default:
QUIC_BUG(quic_bug_10850_57) << "Unknown encryption level: " << level;
}
return false;
}
bool QuicFramer::ProcessIetfFrameData(QuicDataReader* reader,
const QuicPacketHeader& header,
EncryptionLevel decrypted_level) {
QUICHE_DCHECK(VersionHasIetfQuicFrames(version_.transport_version))
<< "Attempt to process frames as IETF frames but version ("
<< version_.transport_version << ") does not support IETF Framing.";
if (reader->IsDoneReading()) {
set_detailed_error("Packet has no frames.");
return RaiseError(QUIC_MISSING_PAYLOAD);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing IETF packet with header " << header;
while (!reader->IsDoneReading()) {
uint64_t frame_type;
// Will be the number of bytes into which frame_type was encoded.
size_t encoded_bytes = reader->BytesRemaining();
if (!reader->ReadVarInt62(&frame_type)) {
set_detailed_error("Unable to read frame type.");
return RaiseError(QUIC_INVALID_FRAME_DATA);
}
if (!IsIetfFrameTypeExpectedForEncryptionLevel(frame_type,
decrypted_level)) {
set_detailed_error(absl::StrCat(
"IETF frame type ",
QuicIetfFrameTypeString(static_cast<QuicIetfFrameType>(frame_type)),
" is unexpected at encryption level ",
EncryptionLevelToString(decrypted_level)));
return RaiseError(IETF_QUIC_PROTOCOL_VIOLATION);
}
current_received_frame_type_ = frame_type;
// Is now the number of bytes into which the frame type was encoded.
encoded_bytes -= reader->BytesRemaining();
// Check that the frame type is minimally encoded.
if (encoded_bytes !=
static_cast<size_t>(QuicDataWriter::GetVarInt62Len(frame_type))) {
// The frame type was not minimally encoded.
set_detailed_error("Frame type not minimally encoded.");
return RaiseError(IETF_QUIC_PROTOCOL_VIOLATION);
}
if (IS_IETF_STREAM_FRAME(frame_type)) {
QuicStreamFrame frame;
if (!ProcessIetfStreamFrame(reader, frame_type, &frame)) {
return RaiseError(QUIC_INVALID_STREAM_DATA);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing IETF stream frame " << frame;
if (!visitor_->OnStreamFrame(frame)) {
QUIC_DVLOG(1) << ENDPOINT
<< "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
} else {
switch (frame_type) {
case IETF_PADDING: {
QuicPaddingFrame frame;
ProcessPaddingFrame(reader, &frame);
QUIC_DVLOG(2) << ENDPOINT << "Processing IETF padding frame "
<< frame;
if (!visitor_->OnPaddingFrame(frame)) {
QUIC_DVLOG(1) << "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
break;
}
case IETF_RST_STREAM: {
QuicRstStreamFrame frame;
if (!ProcessIetfResetStreamFrame(reader, &frame)) {
return RaiseError(QUIC_INVALID_RST_STREAM_DATA);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing IETF reset stream frame "
<< frame;
if (!visitor_->OnRstStreamFrame(frame)) {
QUIC_DVLOG(1) << "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
break;
}
case IETF_APPLICATION_CLOSE:
case IETF_CONNECTION_CLOSE: {
QuicConnectionCloseFrame frame;
if (!ProcessIetfConnectionCloseFrame(
reader,
(frame_type == IETF_CONNECTION_CLOSE)
? IETF_QUIC_TRANSPORT_CONNECTION_CLOSE
: IETF_QUIC_APPLICATION_CONNECTION_CLOSE,
&frame)) {
return RaiseError(QUIC_INVALID_CONNECTION_CLOSE_DATA);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing IETF connection close frame "
<< frame;
if (!visitor_->OnConnectionCloseFrame(frame)) {
QUIC_DVLOG(1) << "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
break;
}
case IETF_MAX_DATA: {
QuicWindowUpdateFrame frame;
if (!ProcessMaxDataFrame(reader, &frame)) {
return RaiseError(QUIC_INVALID_MAX_DATA_FRAME_DATA);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing IETF max data frame "
<< frame;
if (!visitor_->OnWindowUpdateFrame(frame)) {
QUIC_DVLOG(1) << "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
break;
}
case IETF_MAX_STREAM_DATA: {
QuicWindowUpdateFrame frame;
if (!ProcessMaxStreamDataFrame(reader, &frame)) {
return RaiseError(QUIC_INVALID_MAX_STREAM_DATA_FRAME_DATA);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing IETF max stream data frame "
<< frame;
if (!visitor_->OnWindowUpdateFrame(frame)) {
QUIC_DVLOG(1) << "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
break;
}
case IETF_MAX_STREAMS_BIDIRECTIONAL:
case IETF_MAX_STREAMS_UNIDIRECTIONAL: {
QuicMaxStreamsFrame frame;
if (!ProcessMaxStreamsFrame(reader, &frame, frame_type)) {
return RaiseError(QUIC_MAX_STREAMS_DATA);
}
QUIC_CODE_COUNT_N(quic_max_streams_received, 1, 2);
QUIC_DVLOG(2) << ENDPOINT << "Processing IETF max streams frame "
<< frame;
if (!visitor_->OnMaxStreamsFrame(frame)) {
QUIC_DVLOG(1) << "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
break;
}
case IETF_PING: {
// Ping has no payload.
QuicPingFrame ping_frame;
QUIC_DVLOG(2) << ENDPOINT << "Processing IETF ping frame "
<< ping_frame;
if (!visitor_->OnPingFrame(ping_frame)) {
QUIC_DVLOG(1) << "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
break;
}
case IETF_DATA_BLOCKED: {
QuicBlockedFrame frame;
if (!ProcessDataBlockedFrame(reader, &frame)) {
return RaiseError(QUIC_INVALID_BLOCKED_DATA);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing IETF blocked frame "
<< frame;
if (!visitor_->OnBlockedFrame(frame)) {
QUIC_DVLOG(1) << "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
break;
}
case IETF_STREAM_DATA_BLOCKED: {
QuicBlockedFrame frame;
if (!ProcessStreamDataBlockedFrame(reader, &frame)) {
return RaiseError(QUIC_INVALID_STREAM_BLOCKED_DATA);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing IETF stream blocked frame "
<< frame;
if (!visitor_->OnBlockedFrame(frame)) {
QUIC_DVLOG(1) << "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
break;
}
case IETF_STREAMS_BLOCKED_UNIDIRECTIONAL:
case IETF_STREAMS_BLOCKED_BIDIRECTIONAL: {
QuicStreamsBlockedFrame frame;
if (!ProcessStreamsBlockedFrame(reader, &frame, frame_type)) {
return RaiseError(QUIC_STREAMS_BLOCKED_DATA);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing IETF streams blocked frame "
<< frame;
if (!visitor_->OnStreamsBlockedFrame(frame)) {
QUIC_DVLOG(1) << "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
break;
}
case IETF_NEW_CONNECTION_ID: {
QuicNewConnectionIdFrame frame;
if (!ProcessNewConnectionIdFrame(reader, &frame)) {
return RaiseError(QUIC_INVALID_NEW_CONNECTION_ID_DATA);
}
QUIC_DVLOG(2) << ENDPOINT
<< "Processing IETF new connection ID frame " << frame;
if (!visitor_->OnNewConnectionIdFrame(frame)) {
QUIC_DVLOG(1) << "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
break;
}
case IETF_RETIRE_CONNECTION_ID: {
QuicRetireConnectionIdFrame frame;
if (!ProcessRetireConnectionIdFrame(reader, &frame)) {
return RaiseError(QUIC_INVALID_RETIRE_CONNECTION_ID_DATA);
}
QUIC_DVLOG(2) << ENDPOINT
<< "Processing IETF retire connection ID frame "
<< frame;
if (!visitor_->OnRetireConnectionIdFrame(frame)) {
QUIC_DVLOG(1) << "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
break;
}
case IETF_NEW_TOKEN: {
QuicNewTokenFrame frame;
if (!ProcessNewTokenFrame(reader, &frame)) {
return RaiseError(QUIC_INVALID_NEW_TOKEN);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing IETF new token frame "
<< frame;
if (!visitor_->OnNewTokenFrame(frame)) {
QUIC_DVLOG(1) << "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
break;
}
case IETF_STOP_SENDING: {
QuicStopSendingFrame frame;
if (!ProcessStopSendingFrame(reader, &frame)) {
return RaiseError(QUIC_INVALID_STOP_SENDING_FRAME_DATA);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing IETF stop sending frame "
<< frame;
if (!visitor_->OnStopSendingFrame(frame)) {
QUIC_DVLOG(1) << "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
break;
}
case IETF_ACK_ECN:
case IETF_ACK: {
QuicAckFrame frame;
if (!ProcessIetfAckFrame(reader, frame_type, &frame)) {
return RaiseError(QUIC_INVALID_ACK_DATA);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing IETF ACK frame " << frame;
break;
}
case IETF_PATH_CHALLENGE: {
QuicPathChallengeFrame frame;
if (!ProcessPathChallengeFrame(reader, &frame)) {
return RaiseError(QUIC_INVALID_PATH_CHALLENGE_DATA);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing IETF path challenge frame "
<< frame;
if (!visitor_->OnPathChallengeFrame(frame)) {
QUIC_DVLOG(1) << "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
break;
}
case IETF_PATH_RESPONSE: {
QuicPathResponseFrame frame;
if (!ProcessPathResponseFrame(reader, &frame)) {
return RaiseError(QUIC_INVALID_PATH_RESPONSE_DATA);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing IETF path response frame "
<< frame;
if (!visitor_->OnPathResponseFrame(frame)) {
QUIC_DVLOG(1) << "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
break;
}
case IETF_EXTENSION_MESSAGE_NO_LENGTH_V99:
ABSL_FALLTHROUGH_INTENDED;
case IETF_EXTENSION_MESSAGE_V99: {
QuicMessageFrame message_frame;
if (!ProcessMessageFrame(
reader, frame_type == IETF_EXTENSION_MESSAGE_NO_LENGTH_V99,
&message_frame)) {
return RaiseError(QUIC_INVALID_MESSAGE_DATA);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing IETF message frame "
<< message_frame;
if (!visitor_->OnMessageFrame(message_frame)) {
QUIC_DVLOG(1) << ENDPOINT
<< "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
break;
}
case IETF_CRYPTO: {
QuicCryptoFrame frame;
if (!ProcessCryptoFrame(reader, GetEncryptionLevel(header), &frame)) {
return RaiseError(QUIC_INVALID_FRAME_DATA);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing IETF crypto frame " << frame;
if (!visitor_->OnCryptoFrame(frame)) {
QUIC_DVLOG(1) << "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
break;
}
case IETF_HANDSHAKE_DONE: {
// HANDSHAKE_DONE has no payload.
QuicHandshakeDoneFrame handshake_done_frame;
if (!visitor_->OnHandshakeDoneFrame(handshake_done_frame)) {
QUIC_DVLOG(1) << ENDPOINT
<< "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
QUIC_DVLOG(2) << ENDPOINT << "Processing handshake done frame "
<< handshake_done_frame;
break;
}
case IETF_ACK_FREQUENCY: {
QuicAckFrequencyFrame frame;
if (!ProcessAckFrequencyFrame(reader, &frame)) {
return RaiseError(QUIC_INVALID_FRAME_DATA);
}
QUIC_DVLOG(2) << ENDPOINT << "Processing IETF ack frequency frame "
<< frame;
if (!visitor_->OnAckFrequencyFrame(frame)) {
QUIC_DVLOG(1) << "Visitor asked to stop further processing.";
// Returning true since there was no parsing error.
return true;
}
break;
}
default:
set_detailed_error("Illegal frame type.");
QUIC_DLOG(WARNING)
<< ENDPOINT
<< "Illegal frame type: " << static_cast<int>(frame_type);
return RaiseError(QUIC_INVALID_FRAME_DATA);
}
}
}
return true;
}
namespace {
// Create a mask that sets the last |num_bits| to 1 and the rest to 0.
inline uint8_t GetMaskFromNumBits(uint8_t num_bits) {
return (1u << num_bits) - 1;
}
// Extract |num_bits| from |flags| offset by |offset|.
uint8_t ExtractBits(uint8_t flags, uint8_t num_bits, uint8_t offset) {
return (flags >> offset) & GetMaskFromNumBits(num_bits);
}
// Extract the bit at position |offset| from |flags| as a bool.
bool ExtractBit(uint8_t flags, uint8_t offset) {
return ((flags >> offset) & GetMaskFromNumBits(1)) != 0;
}
// Set |num_bits|, offset by |offset| to |val| in |flags|.
void SetBits(uint8_t* flags, uint8_t val, uint8_t num_bits, uint8_t offset) {
QUICHE_DCHECK_LE(val, GetMaskFromNumBits(num_bits));
*flags |= val << offset;
}
// Set the bit at position |offset| to |val| in |flags|.
void SetBit(uint8_t* flags, bool val, uint8_t offset) {
SetBits(flags, val ? 1 : 0, 1, offset);
}
} // namespace
bool QuicFramer::ProcessStreamFrame(QuicDataReader* reader,
uint8_t frame_type,
QuicStreamFrame* frame) {
uint8_t stream_flags = frame_type;
uint8_t stream_id_length = 0;
uint8_t offset_length = 4;
bool has_data_length = true;
stream_flags &= ~kQuicFrameTypeStreamMask;
// Read from right to left: StreamID, Offset, Data Length, Fin.
stream_id_length = (stream_flags & kQuicStreamIDLengthMask) + 1;
stream_flags >>= kQuicStreamIdShift;
offset_length = (stream_flags & kQuicStreamOffsetMask);
// There is no encoding for 1 byte, only 0 and 2 through 8.
if (offset_length > 0) {
offset_length += 1;
}
stream_flags >>= kQuicStreamShift;
has_data_length =
(stream_flags & kQuicStreamDataLengthMask) == kQuicStreamDataLengthMask;
stream_flags >>= kQuicStreamDataLengthShift;
frame->fin = (stream_flags & kQuicStreamFinMask) == kQuicStreamFinShift;
uint64_t stream_id;
if (!reader->ReadBytesToUInt64(stream_id_length, &stream_id)) {
set_detailed_error("Unable to read stream_id.");
return false;
}
frame->stream_id = static_cast<QuicStreamId>(stream_id);
if (!reader->ReadBytesToUInt64(offset_length, &frame->offset)) {
set_detailed_error("Unable to read offset.");
return false;
}
// TODO(ianswett): Don't use absl::string_view as an intermediary.
absl::string_view data;
if (has_data_length) {
if (!reader->ReadStringPiece16(&data)) {
set_detailed_error("Unable to read frame data.");
return false;
}
} else {
if (!reader->ReadStringPiece(&data, reader->BytesRemaining())) {
set_detailed_error("Unable to read frame data.");
return false;
}
}
frame->data_buffer = data.data();
frame->data_length = static_cast<uint16_t>(data.length());
return true;
}
bool QuicFramer::ProcessIetfStreamFrame(QuicDataReader* reader,
uint8_t frame_type,
QuicStreamFrame* frame) {
// Read stream id from the frame. It's always present.
if (!ReadUint32FromVarint62(reader, IETF_STREAM, &frame->stream_id)) {
return false;
}
// If we have a data offset, read it. If not, set to 0.
if (frame_type & IETF_STREAM_FRAME_OFF_BIT) {
if (!reader->ReadVarInt62(&frame->offset)) {
set_detailed_error("Unable to read stream data offset.");
return false;
}
} else {
// no offset in the frame, ensure it's 0 in the Frame.
frame->offset = 0;
}
// If we have a data length, read it. If not, set to 0.
if (frame_type & IETF_STREAM_FRAME_LEN_BIT) {
uint64_t length;
if (!reader->ReadVarInt62(&length)) {
set_detailed_error("Unable to read stream data length.");
return false;
}
if (length > std::numeric_limits<decltype(frame->data_length)>::max()) {
set_detailed_error("Stream data length is too large.");
return false;
}
frame->data_length = length;
} else {
// no length in the frame, it is the number of bytes remaining in the
// packet.
frame->data_length = reader->BytesRemaining();
}
if (frame_type & IETF_STREAM_FRAME_FIN_BIT) {
frame->fin = true;
} else {
frame->fin = false;
}
// TODO(ianswett): Don't use absl::string_view as an intermediary.
absl::string_view data;
if (!reader->ReadStringPiece(&data, frame->data_length)) {
set_detailed_error("Unable to read frame data.");
return false;
}
frame->data_buffer = data.data();
QUICHE_DCHECK_EQ(frame->data_length, data.length());
return true;
}
bool QuicFramer::ProcessCryptoFrame(QuicDataReader* reader,
EncryptionLevel encryption_level,
QuicCryptoFrame* frame) {
frame->level = encryption_level;
if (!reader->ReadVarInt62(&frame->offset)) {
set_detailed_error("Unable to read crypto data offset.");
return false;
}
uint64_t len;
if (!reader->ReadVarInt62(&len) ||
len > std::numeric_limits<QuicPacketLength>::max()) {
set_detailed_error("Invalid data length.");
return false;
}
frame->data_length = len;
// TODO(ianswett): Don't use absl::string_view as an intermediary.
absl::string_view data;
if (!reader->ReadStringPiece(&data, frame->data_length)) {
set_detailed_error("Unable to read frame data.");
return false;
}
frame->data_buffer = data.data();
return true;
}
bool QuicFramer::ProcessAckFrequencyFrame(QuicDataReader* reader,
QuicAckFrequencyFrame* frame) {
if (!reader->ReadVarInt62(&frame->sequence_number)) {
set_detailed_error("Unable to read sequence number.");
return false;
}
if (!reader->ReadVarInt62(&frame->packet_tolerance)) {
set_detailed_error("Unable to read packet tolerance.");
return false;
}
if (frame->packet_tolerance == 0) {
set_detailed_error("Invalid packet tolerance.");
return false;
}
uint64_t max_ack_delay_us;
if (!reader->ReadVarInt62(&max_ack_delay_us)) {
set_detailed_error("Unable to read max_ack_delay_us.");
return false;
}
constexpr uint64_t kMaxAckDelayUsBound = 1u << 24;
if (max_ack_delay_us > kMaxAckDelayUsBound) {
set_detailed_error("Invalid max_ack_delay_us.");
return false;
}
frame->max_ack_delay = QuicTime::Delta::FromMicroseconds(max_ack_delay_us);
uint8_t ignore_order;
if (!reader->ReadUInt8(&ignore_order)) {
set_detailed_error("Unable to read ignore_order.");
return false;
}
if (ignore_order > 1) {
set_detailed_error("Invalid ignore_order.");
return false;
}
frame->ignore_order = ignore_order;
return true;
}
bool QuicFramer::ProcessAckFrame(QuicDataReader* reader, uint8_t frame_type) {
const bool has_ack_blocks =
ExtractBit(frame_type, kQuicHasMultipleAckBlocksOffset);
uint8_t num_ack_blocks = 0;
uint8_t num_received_packets = 0;
// Determine the two lengths from the frame type: largest acked length,
// ack block length.
const QuicPacketNumberLength ack_block_length = ReadAckPacketNumberLength(
ExtractBits(frame_type, kQuicSequenceNumberLengthNumBits,
kActBlockLengthOffset));
const QuicPacketNumberLength largest_acked_length = ReadAckPacketNumberLength(
ExtractBits(frame_type, kQuicSequenceNumberLengthNumBits,
kLargestAckedOffset));
uint64_t largest_acked;
if (!reader->ReadBytesToUInt64(largest_acked_length, &largest_acked)) {
set_detailed_error("Unable to read largest acked.");
return false;
}
if (largest_acked < first_sending_packet_number_.ToUint64()) {
// Connection always sends packet starting from kFirstSendingPacketNumber >
// 0, peer has observed an unsent packet.
set_detailed_error("Largest acked is 0.");
return false;
}
uint64_t ack_delay_time_us;
if (!reader->ReadUFloat16(&ack_delay_time_us)) {
set_detailed_error("Unable to read ack delay time.");
return false;
}
if (!visitor_->OnAckFrameStart(
QuicPacketNumber(largest_acked),
ack_delay_time_us == kUFloat16MaxValue
? QuicTime::Delta::Infinite()
: QuicTime::Delta::FromMicroseconds(ack_delay_time_us))) {
// The visitor suppresses further processing of the packet. Although this is
// not a parsing error, returns false as this is in middle of processing an
// ack frame,
set_detailed_error("Visitor suppresses further processing of ack frame.");
return false;
}
if (has_ack_blocks && !reader->ReadUInt8(&num_ack_blocks)) {
set_detailed_error("Unable to read num of ack blocks.");
return false;
}
uint64_t first_block_length;
if (!reader->ReadBytesToUInt64(ack_block_length, &first_block_length)) {
set_detailed_error("Unable to read first ack block length.");
return false;
}
if (first_block_length == 0) {
set_detailed_error("First block length is zero.");
return false;
}
bool first_ack_block_underflow = first_block_length > largest_acked + 1;
if (first_block_length + first_sending_packet_number_.ToUint64() >
largest_acked + 1) {
first_ack_block_underflow = true;
}
if (first_ack_block_underflow) {
set_detailed_error(absl::StrCat("Underflow with first ack block length ",
first_block_length, " largest acked is ",
largest_acked, ".")
.c_str());
return false;
}
uint64_t first_received = largest_acked + 1 - first_block_length;
if (!visitor_->OnAckRange(QuicPacketNumber(first_received),
QuicPacketNumber(largest_acked + 1))) {
// The visitor suppresses further processing of the packet. Although
// this is not a parsing error, returns false as this is in middle
// of processing an ack frame,
set_detailed_error("Visitor suppresses further processing of ack frame.");
return false;
}
if (num_ack_blocks > 0) {
for (size_t i = 0; i < num_ack_blocks; ++i) {
uint8_t gap = 0;
if (!reader->ReadUInt8(&gap)) {
set_detailed_error("Unable to read gap to next ack block.");
return false;
}
uint64_t current_block_length;
if (!reader->ReadBytesToUInt64(ack_block_length, &current_block_length)) {
set_detailed_error("Unable to ack block length.");
return false;
}
bool ack_block_underflow = first_received < gap + current_block_length;
if (first_received < gap + current_block_length +
first_sending_packet_number_.ToUint64()) {
ack_block_underflow = true;
}
if (ack_block_underflow) {
set_detailed_error(absl::StrCat("Underflow with ack block length ",
current_block_length,
", end of block is ",
first_received - gap, ".")
.c_str());
return false;
}
first_received -= (gap + current_block_length);
if (current_block_length > 0) {
if (!visitor_->OnAckRange(
QuicPacketNumber(first_received),
QuicPacketNumber(first_received) + current_block_length)) {
// The visitor suppresses further processing of the packet. Although
// this is not a parsing error, returns false as this is in middle
// of processing an ack frame,
set_detailed_error(
"Visitor suppresses further processing of ack frame.");
return false;
}
}
}
}
if (!reader->ReadUInt8(&num_received_packets)) {
set_detailed_error("Unable to read num received packets.");
return false;
}
if (!ProcessTimestampsInAckFrame(num_received_packets,
QuicPacketNumber(largest_acked), reader)) {
return false;
}
// Done processing the ACK frame.
if (!visitor_->OnAckFrameEnd(QuicPacketNumber(first_received))) {
set_detailed_error(
"Error occurs when visitor finishes processing the ACK frame.");
return false;
}
return true;
}
bool QuicFramer::ProcessTimestampsInAckFrame(uint8_t num_received_packets,
QuicPacketNumber largest_acked,
QuicDataReader* reader) {
if (num_received_packets == 0) {
return true;
}
uint8_t delta_from_largest_observed;
if (!reader->ReadUInt8(&delta_from_largest_observed)) {
set_detailed_error("Unable to read sequence delta in received packets.");
return false;
}
if (largest_acked.ToUint64() <= delta_from_largest_observed) {
set_detailed_error(
absl::StrCat("delta_from_largest_observed too high: ",
delta_from_largest_observed,
", largest_acked: ", largest_acked.ToUint64())
.c_str());
return false;
}
// Time delta from the framer creation.
uint32_t time_delta_us;
if (!reader->ReadUInt32(&time_delta_us)) {
set_detailed_error("Unable to read time delta in received packets.");
return false;
}
QuicPacketNumber seq_num = largest_acked - delta_from_largest_observed;
if (process_timestamps_) {
last_timestamp_ = CalculateTimestampFromWire(time_delta_us);
visitor_->OnAckTimestamp(seq_num, creation_time_ + last_timestamp_);
}
for (uint8_t i = 1; i < num_received_packets; ++i) {
if (!reader->ReadUInt8(&delta_from_largest_observed)) {
set_detailed_error("Unable to read sequence delta in received packets.");
return false;
}
if (largest_acked.ToUint64() <= delta_from_largest_observed) {
set_detailed_error(
absl::StrCat("delta_from_largest_observed too high: ",
delta_from_largest_observed,
", largest_acked: ", largest_acked.ToUint64())
.c_str());
return false;
}
seq_num = largest_acked - delta_from_largest_observed;
// Time delta from the previous timestamp.
uint64_t incremental_time_delta_us;
if (!reader->ReadUFloat16(&incremental_time_delta_us)) {
set_detailed_error(
"Unable to read incremental time delta in received packets.");
return false;
}
if (process_timestamps_) {
last_timestamp_ = last_timestamp_ + QuicTime::Delta::FromMicroseconds(
incremental_time_delta_us);
visitor_->OnAckTimestamp(seq_num, creation_time_ + last_timestamp_);
}
}
return true;
}
bool QuicFramer::ProcessIetfAckFrame(QuicDataReader* reader,
uint64_t frame_type,
QuicAckFrame* ack_frame) {
uint64_t largest_acked;
if (!reader->ReadVarInt62(&largest_acked)) {
set_detailed_error("Unable to read largest acked.");
return false;
}
if (largest_acked < first_sending_packet_number_.ToUint64()) {
// Connection always sends packet starting from kFirstSendingPacketNumber >
// 0, peer has observed an unsent packet.
set_detailed_error("Largest acked is 0.");
return false;
}
ack_frame->largest_acked = static_cast<QuicPacketNumber>(largest_acked);
uint64_t ack_delay_time_in_us;
if (!reader->ReadVarInt62(&ack_delay_time_in_us)) {
set_detailed_error("Unable to read ack delay time.");
return false;
}
if (ack_delay_time_in_us >= (kVarInt62MaxValue >> peer_ack_delay_exponent_)) {
ack_frame->ack_delay_time = QuicTime::Delta::Infinite();
} else {
ack_delay_time_in_us = (ack_delay_time_in_us << peer_ack_delay_exponent_);
ack_frame->ack_delay_time =
QuicTime::Delta::FromMicroseconds(ack_delay_time_in_us);
}
if (!visitor_->OnAckFrameStart(QuicPacketNumber(largest_acked),
ack_frame->ack_delay_time)) {
// The visitor suppresses further processing of the packet. Although this is
// not a parsing error, returns false as this is in middle of processing an
// ACK frame.
set_detailed_error("Visitor suppresses further processing of ACK frame.");
return false;
}
// Get number of ACK blocks from the packet.
uint64_t ack_block_count;
if (!reader->ReadVarInt62(&ack_block_count)) {
set_detailed_error("Unable to read ack block count.");
return false;
}
// There always is a first ACK block, which is the (number of packets being
// acked)-1, up to and including the packet at largest_acked. Therefore if the
// value is 0, then only largest is acked. If it is 1, then largest-1,
// largest] are acked, etc
uint64_t ack_block_value;
if (!reader->ReadVarInt62(&ack_block_value)) {
set_detailed_error("Unable to read first ack block length.");
return false;
}
// Calculate the packets being acked in the first block.
// +1 because AddRange implementation requires [low,high)
uint64_t block_high = largest_acked + 1;
uint64_t block_low = largest_acked - ack_block_value;
// ack_block_value is the number of packets preceding the
// largest_acked packet which are in the block being acked. Thus,
// its maximum value is largest_acked-1. Test this, reporting an
// error if the value is wrong.
if (ack_block_value + first_sending_packet_number_.ToUint64() >
largest_acked) {
set_detailed_error(absl::StrCat("Underflow with first ack block length ",
ack_block_value + 1, " largest acked is ",
largest_acked, ".")
.c_str());
return false;
}
if (!visitor_->OnAckRange(QuicPacketNumber(block_low),
QuicPacketNumber(block_high))) {
// The visitor suppresses further processing of the packet. Although
// this is not a parsing error, returns false as this is in middle
// of processing an ACK frame.
set_detailed_error("Visitor suppresses further processing of ACK frame.");
return false;
}
while (ack_block_count != 0) {
uint64_t gap_block_value;
// Get the sizes of the gap and ack blocks,
if (!reader->ReadVarInt62(&gap_block_value)) {
set_detailed_error("Unable to read gap block value.");
return false;
}
// It's an error if the gap is larger than the space from packet
// number 0 to the start of the block that's just been acked, PLUS
// there must be space for at least 1 packet to be acked. For
// example, if block_low is 10 and gap_block_value is 9, it means
// the gap block is 10 packets long, leaving no room for a packet
// to be acked. Thus, gap_block_value+2 can not be larger than
// block_low.
// The test is written this way to detect wrap-arounds.
if ((gap_block_value + 2) > block_low) {
set_detailed_error(
absl::StrCat("Underflow with gap block length ", gap_block_value + 1,
" previous ack block start is ", block_low, ".")
.c_str());
return false;
}
// Adjust block_high to be the top of the next ack block.
// There is a gap of |gap_block_value| packets between the bottom
// of ack block N and top of block N+1. Note that gap_block_value
// is he size of the gap minus 1 (per the QUIC protocol), and
// block_high is the packet number of the first packet of the gap
// (per the implementation of OnAckRange/AddAckRange, below).
block_high = block_low - 1 - gap_block_value;
if (!reader->ReadVarInt62(&ack_block_value)) {
set_detailed_error("Unable to read ack block value.");
return false;
}
if (ack_block_value + first_sending_packet_number_.ToUint64() >
(block_high - 1)) {
set_detailed_error(
absl::StrCat("Underflow with ack block length ", ack_block_value + 1,
" latest ack block end is ", block_high - 1, ".")
.c_str());
return false;
}
// Calculate the low end of the new nth ack block. The +1 is
// because the encoded value is the blocksize-1.
block_low = block_high - 1 - ack_block_value;
if (!visitor_->OnAckRange(QuicPacketNumber(block_low),
QuicPacketNumber(block_high))) {
// The visitor suppresses further processing of the packet. Although
// this is not a parsing error, returns false as this is in middle
// of processing an ACK frame.
set_detailed_error("Visitor suppresses further processing of ACK frame.");
return false;
}
// Another one done.
ack_block_count--;
}
if (frame_type == IETF_ACK_ECN) {
ack_frame->ecn_counters_populated = true;
if (!reader->ReadVarInt62(&ack_frame->ect_0_count)) {
set_detailed_error("Unable to read ack ect_0_count.");
return false;
}
if (!reader->ReadVarInt62(&ack_frame->ect_1_count)) {
set_detailed_error("Unable to read ack ect_1_count.");
return false;
}
if (!reader->ReadVarInt62(&ack_frame->ecn_ce_count)) {
set_detailed_error("Unable to read ack ecn_ce_count.");
return false;
}
} else {
ack_frame->ecn_counters_populated = false;
ack_frame->ect_0_count = 0;
ack_frame->ect_1_count = 0;
ack_frame->ecn_ce_count = 0;
}
// TODO(fayang): Report ECN counts to visitor when they are actually used.
if (!visitor_->OnAckFrameEnd(QuicPacketNumber(block_low))) {
set_detailed_error(
"Error occurs when visitor finishes processing the ACK frame.");
return false;
}
return true;
}
bool QuicFramer::ProcessStopWaitingFrame(QuicDataReader* reader,
const QuicPacketHeader& header,
QuicStopWaitingFrame* stop_waiting) {
uint64_t least_unacked_delta;
if (!reader->ReadBytesToUInt64(header.packet_number_length,
&least_unacked_delta)) {
set_detailed_error("Unable to read least unacked delta.");
return false;
}
if (header.packet_number.ToUint64() <= least_unacked_delta) {
set_detailed_error("Invalid unacked delta.");
return false;
}
stop_waiting->least_unacked = header.packet_number - least_unacked_delta;
return true;
}
bool QuicFramer::ProcessRstStreamFrame(QuicDataReader* reader,
QuicRstStreamFrame* frame) {
if (!reader->ReadUInt32(&frame->stream_id)) {
set_detailed_error("Unable to read stream_id.");
return false;
}
if (!reader->ReadUInt64(&frame->byte_offset)) {
set_detailed_error("Unable to read rst stream sent byte offset.");
return false;
}
uint32_t error_code;
if (!reader->ReadUInt32(&error_code)) {
set_detailed_error("Unable to read rst stream error code.");
return false;
}
if (error_code >= QUIC_STREAM_LAST_ERROR) {
// Ignore invalid stream error code if any.
error_code = QUIC_STREAM_LAST_ERROR;
}
frame->error_code = static_cast<QuicRstStreamErrorCode>(error_code);
return true;
}
bool QuicFramer::ProcessConnectionCloseFrame(QuicDataReader* reader,
QuicConnectionCloseFrame* frame) {
uint32_t error_code;
frame->close_type = GOOGLE_QUIC_CONNECTION_CLOSE;
if (!reader->ReadUInt32(&error_code)) {
set_detailed_error("Unable to read connection close error code.");
return false;
}
// For Google QUIC connection closes, |wire_error_code| and |quic_error_code|
// must have the same value.
frame->wire_error_code = error_code;
frame->quic_error_code = static_cast<QuicErrorCode>(error_code);
absl::string_view error_details;
if (!reader->ReadStringPiece16(&error_details)) {
set_detailed_error("Unable to read connection close error details.");
return false;
}
frame->error_details = std::string(error_details);
return true;
}
bool QuicFramer::ProcessGoAwayFrame(QuicDataReader* reader,
QuicGoAwayFrame* frame) {
uint32_t error_code;
if (!reader->ReadUInt32(&error_code)) {
set_detailed_error("Unable to read go away error code.");
return false;
}
frame->error_code = static_cast<QuicErrorCode>(error_code);
uint32_t stream_id;
if (!reader->ReadUInt32(&stream_id)) {
set_detailed_error("Unable to read last good stream id.");
return false;
}
frame->last_good_stream_id = static_cast<QuicStreamId>(stream_id);
absl::string_view reason_phrase;
if (!reader->ReadStringPiece16(&reason_phrase)) {
set_detailed_error("Unable to read goaway reason.");
return false;
}
frame->reason_phrase = std::string(reason_phrase);
return true;
}
bool QuicFramer::ProcessWindowUpdateFrame(QuicDataReader* reader,
QuicWindowUpdateFrame* frame) {
if (!reader->ReadUInt32(&frame->stream_id)) {
set_detailed_error("Unable to read stream_id.");
return false;
}
if (!reader->ReadUInt64(&frame->max_data)) {
set_detailed_error("Unable to read window byte_offset.");
return false;
}
return true;
}
bool QuicFramer::ProcessBlockedFrame(QuicDataReader* reader,
QuicBlockedFrame* frame) {
QUICHE_DCHECK(!VersionHasIetfQuicFrames(version_.transport_version))
<< "Attempt to process non-IETF QUIC frames in an IETF QUIC version.";
if (!reader->ReadUInt32(&frame->stream_id)) {
set_detailed_error("Unable to read stream_id.");
return false;
}
return true;
}
void QuicFramer::ProcessPaddingFrame(QuicDataReader* reader,
QuicPaddingFrame* frame) {
// Type byte has been read.
frame->num_padding_bytes = 1;
uint8_t next_byte;
while (!reader->IsDoneReading() && reader->PeekByte() == 0x00) {
reader->ReadBytes(&next_byte, 1);
QUICHE_DCHECK_EQ(0x00, next_byte);
++frame->num_padding_bytes;
}
}
bool QuicFramer::ProcessMessageFrame(QuicDataReader* reader,
bool no_message_length,
QuicMessageFrame* frame) {
if (no_message_length) {
absl::string_view remaining(reader->ReadRemainingPayload());
frame->data = remaining.data();
frame->message_length = remaining.length();
return true;
}
uint64_t message_length;
if (!reader->ReadVarInt62(&message_length)) {
set_detailed_error("Unable to read message length");
return false;
}
absl::string_view message_piece;
if (!reader->ReadStringPiece(&message_piece, message_length)) {
set_detailed_error("Unable to read message data");
return false;
}
frame->data = message_piece.data();
frame->message_length = message_length;
return true;
}
// static
absl::string_view QuicFramer::GetAssociatedDataFromEncryptedPacket(
QuicTransportVersion version,
const QuicEncryptedPacket& encrypted,
QuicConnectionIdLength destination_connection_id_length,
QuicConnectionIdLength source_connection_id_length,
bool includes_version,
bool includes_diversification_nonce,
QuicPacketNumberLength packet_number_length,
QuicVariableLengthIntegerLength retry_token_length_length,
uint64_t retry_token_length,
QuicVariableLengthIntegerLength length_length) {
// TODO(ianswett): This is identical to QuicData::AssociatedData.
return absl::string_view(
encrypted.data(),
GetStartOfEncryptedData(version, destination_connection_id_length,
source_connection_id_length, includes_version,
includes_diversification_nonce,
packet_number_length, retry_token_length_length,
retry_token_length, length_length));
}
void QuicFramer::SetDecrypter(EncryptionLevel level,
std::unique_ptr<QuicDecrypter> decrypter) {
QUICHE_DCHECK_EQ(alternative_decrypter_level_, NUM_ENCRYPTION_LEVELS);
QUICHE_DCHECK_GE(level, decrypter_level_);
QUICHE_DCHECK(!version_.KnowsWhichDecrypterToUse());
QUIC_DVLOG(1) << ENDPOINT << "Setting decrypter from level "
<< decrypter_level_ << " to " << level;
decrypter_[decrypter_level_] = nullptr;
decrypter_[level] = std::move(decrypter);
decrypter_level_ = level;
}
void QuicFramer::SetAlternativeDecrypter(
EncryptionLevel level,
std::unique_ptr<QuicDecrypter> decrypter,
bool latch_once_used) {
QUICHE_DCHECK_NE(level, decrypter_level_);
QUICHE_DCHECK(!version_.KnowsWhichDecrypterToUse());
QUIC_DVLOG(1) << ENDPOINT << "Setting alternative decrypter from level "
<< alternative_decrypter_level_ << " to " << level;
if (alternative_decrypter_level_ != NUM_ENCRYPTION_LEVELS) {
decrypter_[alternative_decrypter_level_] = nullptr;
}
decrypter_[level] = std::move(decrypter);
alternative_decrypter_level_ = level;
alternative_decrypter_latch_ = latch_once_used;
}
void QuicFramer::InstallDecrypter(EncryptionLevel level,
std::unique_ptr<QuicDecrypter> decrypter) {
QUICHE_DCHECK(version_.KnowsWhichDecrypterToUse());
QUIC_DVLOG(1) << ENDPOINT << "Installing decrypter at level " << level;
decrypter_[level] = std::move(decrypter);
}
void QuicFramer::RemoveDecrypter(EncryptionLevel level) {
QUICHE_DCHECK(version_.KnowsWhichDecrypterToUse());
QUIC_DVLOG(1) << ENDPOINT << "Removing decrypter at level " << level;
decrypter_[level] = nullptr;
}
void QuicFramer::SetKeyUpdateSupportForConnection(bool enabled) {
QUIC_DVLOG(1) << ENDPOINT << "SetKeyUpdateSupportForConnection: " << enabled;
support_key_update_for_connection_ = enabled;
}
void QuicFramer::DiscardPreviousOneRttKeys() {
QUICHE_DCHECK(support_key_update_for_connection_);
QUIC_DVLOG(1) << ENDPOINT << "Discarding previous set of 1-RTT keys";
previous_decrypter_ = nullptr;
}
bool QuicFramer::DoKeyUpdate(KeyUpdateReason reason) {
QUICHE_DCHECK(support_key_update_for_connection_);
if (!next_decrypter_) {
// If key update is locally initiated, next decrypter might not be created
// yet.
next_decrypter_ = visitor_->AdvanceKeysAndCreateCurrentOneRttDecrypter();
}
std::unique_ptr<QuicEncrypter> next_encrypter =
visitor_->CreateCurrentOneRttEncrypter();
if (!next_decrypter_ || !next_encrypter) {
QUIC_BUG(quic_bug_10850_58) << "Failed to create next crypters";
return false;
}
key_update_performed_ = true;
current_key_phase_bit_ = !current_key_phase_bit_;
QUIC_DLOG(INFO) << ENDPOINT << "DoKeyUpdate: new current_key_phase_bit_="
<< current_key_phase_bit_;
current_key_phase_first_received_packet_number_.Clear();
previous_decrypter_ = std::move(decrypter_[ENCRYPTION_FORWARD_SECURE]);
decrypter_[ENCRYPTION_FORWARD_SECURE] = std::move(next_decrypter_);
encrypter_[ENCRYPTION_FORWARD_SECURE] = std::move(next_encrypter);
visitor_->OnKeyUpdate(reason);
return true;
}
QuicPacketCount QuicFramer::PotentialPeerKeyUpdateAttemptCount() const {
return potential_peer_key_update_attempt_count_;
}
const QuicDecrypter* QuicFramer::GetDecrypter(EncryptionLevel level) const {
QUICHE_DCHECK(version_.KnowsWhichDecrypterToUse());
return decrypter_[level].get();
}
const QuicDecrypter* QuicFramer::decrypter() const {
return decrypter_[decrypter_level_].get();
}
const QuicDecrypter* QuicFramer::alternative_decrypter() const {
if (alternative_decrypter_level_ == NUM_ENCRYPTION_LEVELS) {
return nullptr;
}
return decrypter_[alternative_decrypter_level_].get();
}
void QuicFramer::SetEncrypter(EncryptionLevel level,
std::unique_ptr<QuicEncrypter> encrypter) {
QUICHE_DCHECK_GE(level, 0);
QUICHE_DCHECK_LT(level, NUM_ENCRYPTION_LEVELS);
QUIC_DVLOG(1) << ENDPOINT << "Setting encrypter at level " << level;
encrypter_[level] = std::move(encrypter);
}
void QuicFramer::RemoveEncrypter(EncryptionLevel level) {
QUIC_DVLOG(1) << ENDPOINT << "Removing encrypter of " << level;
encrypter_[level] = nullptr;
}
void QuicFramer::SetInitialObfuscators(QuicConnectionId connection_id) {
CrypterPair crypters;
CryptoUtils::CreateInitialObfuscators(perspective_, version_, connection_id,
&crypters);
encrypter_[ENCRYPTION_INITIAL] = std::move(crypters.encrypter);
decrypter_[ENCRYPTION_INITIAL] = std::move(crypters.decrypter);
}
size_t QuicFramer::EncryptInPlace(EncryptionLevel level,
QuicPacketNumber packet_number,
size_t ad_len,
size_t total_len,
size_t buffer_len,
char* buffer) {
QUICHE_DCHECK(packet_number.IsInitialized());
if (encrypter_[level] == nullptr) {
QUIC_BUG(quic_bug_10850_59)
<< ENDPOINT
<< "Attempted to encrypt in place without encrypter at level " << level;
RaiseError(QUIC_ENCRYPTION_FAILURE);
return 0;
}
size_t output_length = 0;
if (!encrypter_[level]->EncryptPacket(
packet_number.ToUint64(),
absl::string_view(buffer, ad_len), // Associated data
absl::string_view(buffer + ad_len,
total_len - ad_len), // Plaintext
buffer + ad_len, // Destination buffer
&output_length, buffer_len - ad_len)) {
RaiseError(QUIC_ENCRYPTION_FAILURE);
return 0;
}
if (version_.HasHeaderProtection() &&
!ApplyHeaderProtection(level, buffer, ad_len + output_length, ad_len)) {
QUIC_DLOG(ERROR) << "Applying header protection failed.";
RaiseError(QUIC_ENCRYPTION_FAILURE);
return 0;
}
return ad_len + output_length;
}
namespace {
const size_t kHPSampleLen = 16;
constexpr bool IsLongHeader(uint8_t type_byte) {
return (type_byte & FLAGS_LONG_HEADER) != 0;
}
} // namespace
bool QuicFramer::ApplyHeaderProtection(EncryptionLevel level,
char* buffer,
size_t buffer_len,
size_t ad_len) {
QuicDataReader buffer_reader(buffer, buffer_len);
QuicDataWriter buffer_writer(buffer_len, buffer);
// The sample starts 4 bytes after the start of the packet number.
if (ad_len < last_written_packet_number_length_) {
return false;
}
size_t pn_offset = ad_len - last_written_packet_number_length_;
// Sample the ciphertext and generate the mask to use for header protection.
size_t sample_offset = pn_offset + 4;
QuicDataReader sample_reader(buffer, buffer_len);
absl::string_view sample;
if (!sample_reader.Seek(sample_offset) ||
!sample_reader.ReadStringPiece(&sample, kHPSampleLen)) {
QUIC_BUG(quic_bug_10850_60)
<< "Not enough bytes to sample: sample_offset " << sample_offset
<< ", sample len: " << kHPSampleLen << ", buffer len: " << buffer_len;
return false;
}
if (encrypter_[level] == nullptr) {
QUIC_BUG(quic_bug_12975_8)
<< ENDPOINT
<< "Attempted to apply header protection without encrypter at level "
<< level << " using " << version_;
return false;
}
std::string mask = encrypter_[level]->GenerateHeaderProtectionMask(sample);
if (mask.empty()) {
QUIC_BUG(quic_bug_10850_61) << "Unable to generate header protection mask.";
return false;
}
QuicDataReader mask_reader(mask.data(), mask.size());
// Apply the mask to the 4 or 5 least significant bits of the first byte.
uint8_t bitmask = 0x1f;
uint8_t type_byte;
if (!buffer_reader.ReadUInt8(&type_byte)) {
return false;
}
QuicLongHeaderType header_type;
if (IsLongHeader(type_byte)) {
bitmask = 0x0f;
if (!GetLongHeaderType(type_byte, &header_type)) {
return false;
}
}
uint8_t mask_byte;
if (!mask_reader.ReadUInt8(&mask_byte) ||
!buffer_writer.WriteUInt8(type_byte ^ (mask_byte & bitmask))) {
return false;
}
// Adjust |pn_offset| to account for the diversification nonce.
if (IsLongHeader(type_byte) && header_type == ZERO_RTT_PROTECTED &&
perspective_ == Perspective::IS_SERVER &&
version_.handshake_protocol == PROTOCOL_QUIC_CRYPTO) {
if (pn_offset <= kDiversificationNonceSize) {
QUIC_BUG(quic_bug_10850_62)
<< "Expected diversification nonce, but not enough bytes";
return false;
}
pn_offset -= kDiversificationNonceSize;
}
// Advance the reader and writer to the packet number. Both the reader and
// writer have each read/written one byte.
if (!buffer_writer.Seek(pn_offset - 1) ||
!buffer_reader.Seek(pn_offset - 1)) {
return false;
}
// Apply the rest of the mask to the packet number.
for (size_t i = 0; i < last_written_packet_number_length_; ++i) {
uint8_t buffer_byte;
uint8_t mask_byte;
if (!mask_reader.ReadUInt8(&mask_byte) ||
!buffer_reader.ReadUInt8(&buffer_byte) ||
!buffer_writer.WriteUInt8(buffer_byte ^ mask_byte)) {
return false;
}
}
return true;
}
bool QuicFramer::RemoveHeaderProtection(QuicDataReader* reader,
const QuicEncryptedPacket& packet,
QuicPacketHeader* header,
uint64_t* full_packet_number,
std::vector<char>* associated_data) {
EncryptionLevel expected_decryption_level = GetEncryptionLevel(*header);
QuicDecrypter* decrypter = decrypter_[expected_decryption_level].get();
if (decrypter == nullptr) {
QUIC_DVLOG(1)
<< ENDPOINT
<< "No decrypter available for removing header protection at level "
<< expected_decryption_level;
return false;
}
bool has_diversification_nonce =
header->form == IETF_QUIC_LONG_HEADER_PACKET &&
header->long_packet_type == ZERO_RTT_PROTECTED &&
perspective_ == Perspective::IS_CLIENT &&
version_.handshake_protocol == PROTOCOL_QUIC_CRYPTO;
// Read a sample from the ciphertext and compute the mask to use for header
// protection.
absl::string_view remaining_packet = reader->PeekRemainingPayload();
QuicDataReader sample_reader(remaining_packet);
// The sample starts 4 bytes after the start of the packet number.
absl::string_view pn;
if (!sample_reader.ReadStringPiece(&pn, 4)) {
QUIC_DVLOG(1) << "Not enough data to sample";
return false;
}
if (has_diversification_nonce) {
// In Google QUIC, the diversification nonce comes between the packet number
// and the sample.
if (!sample_reader.Seek(kDiversificationNonceSize)) {
QUIC_DVLOG(1) << "No diversification nonce to skip over";
return false;
}
}
std::string mask = decrypter->GenerateHeaderProtectionMask(&sample_reader);
QuicDataReader mask_reader(mask.data(), mask.size());
if (mask.empty()) {
QUIC_DVLOG(1) << "Failed to compute mask";
return false;
}
// Unmask the rest of the type byte.
uint8_t bitmask = 0x1f;
if (IsLongHeader(header->type_byte)) {
bitmask = 0x0f;
}
uint8_t mask_byte;
if (!mask_reader.ReadUInt8(&mask_byte)) {
QUIC_DVLOG(1) << "No first byte to read from mask";
return false;
}
header->type_byte ^= (mask_byte & bitmask);
// Compute the packet number length.
header->packet_number_length =
static_cast<QuicPacketNumberLength>((header->type_byte & 0x03) + 1);
char pn_buffer[IETF_MAX_PACKET_NUMBER_LENGTH] = {};
QuicDataWriter pn_writer(ABSL_ARRAYSIZE(pn_buffer), pn_buffer);
// Read the (protected) packet number from the reader and unmask the packet
// number.
for (size_t i = 0; i < header->packet_number_length; ++i) {
uint8_t protected_pn_byte, mask_byte;
if (!mask_reader.ReadUInt8(&mask_byte) ||
!reader->ReadUInt8(&protected_pn_byte) ||
!pn_writer.WriteUInt8(protected_pn_byte ^ mask_byte)) {
QUIC_DVLOG(1) << "Failed to unmask packet number";
return false;
}
}
QuicDataReader packet_number_reader(pn_writer.data(), pn_writer.length());
QuicPacketNumber base_packet_number;
if (supports_multiple_packet_number_spaces_) {
PacketNumberSpace pn_space = GetPacketNumberSpace(*header);
if (pn_space == NUM_PACKET_NUMBER_SPACES) {
return false;
}
base_packet_number = largest_decrypted_packet_numbers_[pn_space];
} else {
base_packet_number = largest_packet_number_;
}
if (!ProcessAndCalculatePacketNumber(
&packet_number_reader, header->packet_number_length,
base_packet_number, full_packet_number)) {
return false;
}
// Get the associated data, and apply the same unmasking operations to it.
absl::string_view ad = GetAssociatedDataFromEncryptedPacket(
version_.transport_version, packet,
GetIncludedDestinationConnectionIdLength(*header),
GetIncludedSourceConnectionIdLength(*header), header->version_flag,
has_diversification_nonce, header->packet_number_length,
header->retry_token_length_length, header->retry_token.length(),
header->length_length);
*associated_data = std::vector<char>(ad.begin(), ad.end());
QuicDataWriter ad_writer(associated_data->size(), associated_data->data());
// Apply the unmasked type byte and packet number to |associated_data|.
if (!ad_writer.WriteUInt8(header->type_byte)) {
return false;
}
// Put the packet number at the end of the AD, or if there's a diversification
// nonce, before that (which is at the end of the AD).
size_t seek_len = ad_writer.remaining() - header->packet_number_length;
if (has_diversification_nonce) {
seek_len -= kDiversificationNonceSize;
}
if (!ad_writer.Seek(seek_len) ||
!ad_writer.WriteBytes(pn_writer.data(), pn_writer.length())) {
QUIC_DVLOG(1) << "Failed to apply unmasking operations to AD";
return false;
}
return true;
}
size_t QuicFramer::EncryptPayload(EncryptionLevel level,
QuicPacketNumber packet_number,
const QuicPacket& packet,
char* buffer,
size_t buffer_len) {
QUICHE_DCHECK(packet_number.IsInitialized());
if (encrypter_[level] == nullptr) {
QUIC_BUG(quic_bug_10850_63)
<< ENDPOINT << "Attempted to encrypt without encrypter at level "
<< level;
RaiseError(QUIC_ENCRYPTION_FAILURE);
return 0;
}
absl::string_view associated_data =
packet.AssociatedData(version_.transport_version);
// Copy in the header, because the encrypter only populates the encrypted
// plaintext content.
const size_t ad_len = associated_data.length();
if (packet.length() < ad_len) {
QUIC_BUG(quic_bug_10850_64)
<< ENDPOINT << "packet is shorter than associated data length. version:"
<< version() << ", packet length:" << packet.length()
<< ", associated data length:" << ad_len;
RaiseError(QUIC_ENCRYPTION_FAILURE);
return 0;
}
memmove(buffer, associated_data.data(), ad_len);
// Encrypt the plaintext into the buffer.
size_t output_length = 0;
if (!encrypter_[level]->EncryptPacket(
packet_number.ToUint64(), associated_data,
packet.Plaintext(version_.transport_version), buffer + ad_len,
&output_length, buffer_len - ad_len)) {
RaiseError(QUIC_ENCRYPTION_FAILURE);
return 0;
}
if (version_.HasHeaderProtection() &&
!ApplyHeaderProtection(level, buffer, ad_len + output_length, ad_len)) {
QUIC_DLOG(ERROR) << "Applying header protection failed.";
RaiseError(QUIC_ENCRYPTION_FAILURE);
return 0;
}
return ad_len + output_length;
}
size_t QuicFramer::GetCiphertextSize(EncryptionLevel level,
size_t plaintext_size) const {
if (encrypter_[level] == nullptr) {
QUIC_BUG(quic_bug_10850_65)
<< ENDPOINT
<< "Attempted to get ciphertext size without encrypter at level "
<< level << " using " << version_;
return plaintext_size;
}
return encrypter_[level]->GetCiphertextSize(plaintext_size);
}
size_t QuicFramer::GetMaxPlaintextSize(size_t ciphertext_size) {
// In order to keep the code simple, we don't have the current encryption
// level to hand. Both the NullEncrypter and AES-GCM have a tag length of 12.
size_t min_plaintext_size = ciphertext_size;
for (int i = ENCRYPTION_INITIAL; i < NUM_ENCRYPTION_LEVELS; i++) {
if (encrypter_[i] != nullptr) {
size_t size = encrypter_[i]->GetMaxPlaintextSize(ciphertext_size);
if (size < min_plaintext_size) {
min_plaintext_size = size;
}
}
}
return min_plaintext_size;
}
QuicPacketCount QuicFramer::GetOneRttEncrypterConfidentialityLimit() const {
if (!encrypter_[ENCRYPTION_FORWARD_SECURE]) {
QUIC_BUG(quic_bug_10850_66) << "1-RTT encrypter not set";
return 0;
}
return encrypter_[ENCRYPTION_FORWARD_SECURE]->GetConfidentialityLimit();
}
bool QuicFramer::DecryptPayload(size_t udp_packet_length,
absl::string_view encrypted,
absl::string_view associated_data,
const QuicPacketHeader& header,
char* decrypted_buffer,
size_t buffer_length,
size_t* decrypted_length,
EncryptionLevel* decrypted_level) {
if (!EncryptionLevelIsValid(decrypter_level_)) {
QUIC_BUG(quic_bug_10850_67)
<< "Attempted to decrypt with bad decrypter_level_";
return false;
}
EncryptionLevel level = decrypter_level_;
QuicDecrypter* decrypter = decrypter_[level].get();
QuicDecrypter* alternative_decrypter = nullptr;
bool key_phase_parsed = false;
bool key_phase;
bool attempt_key_update = false;
if (version().KnowsWhichDecrypterToUse()) {
if (header.form == GOOGLE_QUIC_PACKET) {
QUIC_BUG(quic_bug_10850_68)
<< "Attempted to decrypt GOOGLE_QUIC_PACKET with a version that "
"knows which decrypter to use";
return false;
}
level = GetEncryptionLevel(header);
if (!EncryptionLevelIsValid(level)) {
QUIC_BUG(quic_bug_10850_69) << "Attempted to decrypt with bad level";
return false;
}
decrypter = decrypter_[level].get();
if (decrypter == nullptr) {
return false;
}
if (level == ENCRYPTION_ZERO_RTT &&
perspective_ == Perspective::IS_CLIENT && header.nonce != nullptr) {
decrypter->SetDiversificationNonce(*header.nonce);
}
if (support_key_update_for_connection_ &&
header.form == IETF_QUIC_SHORT_HEADER_PACKET) {
QUICHE_DCHECK(version().UsesTls());
QUICHE_DCHECK_EQ(level, ENCRYPTION_FORWARD_SECURE);
key_phase = (header.type_byte & FLAGS_KEY_PHASE_BIT) != 0;
key_phase_parsed = true;
QUIC_DVLOG(1) << ENDPOINT << "packet " << header.packet_number
<< " received key_phase=" << key_phase
<< " current_key_phase_bit_=" << current_key_phase_bit_;
if (key_phase != current_key_phase_bit_) {
if ((current_key_phase_first_received_packet_number_.IsInitialized() &&
header.packet_number >
current_key_phase_first_received_packet_number_) ||
(!current_key_phase_first_received_packet_number_.IsInitialized() &&
!key_update_performed_)) {
if (!next_decrypter_) {
next_decrypter_ =
visitor_->AdvanceKeysAndCreateCurrentOneRttDecrypter();
if (!next_decrypter_) {
QUIC_BUG(quic_bug_10850_70) << "Failed to create next_decrypter";
return false;
}
}
QUIC_DVLOG(1) << ENDPOINT << "packet " << header.packet_number
<< " attempt_key_update=true";
attempt_key_update = true;
potential_peer_key_update_attempt_count_++;
decrypter = next_decrypter_.get();
} else {
if (previous_decrypter_) {
QUIC_DVLOG(1) << ENDPOINT
<< "trying previous_decrypter_ for packet "
<< header.packet_number;
decrypter = previous_decrypter_.get();
} else {
QUIC_DVLOG(1) << ENDPOINT << "dropping packet "
<< header.packet_number << " with old key phase";
return false;
}
}
}
}
} else if (alternative_decrypter_level_ != NUM_ENCRYPTION_LEVELS) {
if (!EncryptionLevelIsValid(alternative_decrypter_level_)) {
QUIC_BUG(quic_bug_10850_71)
<< "Attempted to decrypt with bad alternative_decrypter_level_";
return false;
}
alternative_decrypter = decrypter_[alternative_decrypter_level_].get();
}
if (decrypter == nullptr) {
QUIC_BUG(quic_bug_10850_72)
<< "Attempting to decrypt without decrypter, encryption level:" << level
<< " version:" << version();
return false;
}
bool success = decrypter->DecryptPacket(
header.packet_number.ToUint64(), associated_data, encrypted,
decrypted_buffer, decrypted_length, buffer_length);
if (success) {
visitor_->OnDecryptedPacket(udp_packet_length, level);
if (level == ENCRYPTION_ZERO_RTT &&
current_key_phase_first_received_packet_number_.IsInitialized() &&
header.packet_number >
current_key_phase_first_received_packet_number_) {
set_detailed_error(absl::StrCat(
"Decrypted a 0-RTT packet with a packet number ",
header.packet_number.ToString(),
" which is higher than a 1-RTT packet number ",
current_key_phase_first_received_packet_number_.ToString()));
return RaiseError(QUIC_INVALID_0RTT_PACKET_NUMBER_OUT_OF_ORDER);
}
*decrypted_level = level;
potential_peer_key_update_attempt_count_ = 0;
if (attempt_key_update) {
if (!DoKeyUpdate(KeyUpdateReason::kRemote)) {
set_detailed_error("Key update failed due to internal error");
return RaiseError(QUIC_INTERNAL_ERROR);
}
QUICHE_DCHECK_EQ(current_key_phase_bit_, key_phase);
}
if (key_phase_parsed &&
!current_key_phase_first_received_packet_number_.IsInitialized() &&
key_phase == current_key_phase_bit_) {
// Set packet number for current key phase if it hasn't been initialized
// yet. This is set outside of attempt_key_update since the key update
// may have been initiated locally, and in that case we don't know yet
// which packet number from the remote side to use until we receive a
// packet with that phase.
QUIC_DVLOG(1) << ENDPOINT
<< "current_key_phase_first_received_packet_number_ = "
<< header.packet_number;
current_key_phase_first_received_packet_number_ = header.packet_number;
visitor_->OnDecryptedFirstPacketInKeyPhase();
}
} else if (alternative_decrypter != nullptr) {
if (header.nonce != nullptr) {
QUICHE_DCHECK_EQ(perspective_, Perspective::IS_CLIENT);
alternative_decrypter->SetDiversificationNonce(*header.nonce);
}
bool try_alternative_decryption = true;
if (alternative_decrypter_level_ == ENCRYPTION_ZERO_RTT) {
if (perspective_ == Perspective::IS_CLIENT) {
if (header.nonce == nullptr) {
// Can not use INITIAL decryption without a diversification nonce.
try_alternative_decryption = false;
}
} else {
QUICHE_DCHECK(header.nonce == nullptr);
}
}
if (try_alternative_decryption) {
success = alternative_decrypter->DecryptPacket(
header.packet_number.ToUint64(), associated_data, encrypted,
decrypted_buffer, decrypted_length, buffer_length);
}
if (success) {
visitor_->OnDecryptedPacket(udp_packet_length,
alternative_decrypter_level_);
*decrypted_level = decrypter_level_;
if (alternative_decrypter_latch_) {
if (!EncryptionLevelIsValid(alternative_decrypter_level_)) {
QUIC_BUG(quic_bug_10850_73)
<< "Attempted to latch alternate decrypter with bad "
"alternative_decrypter_level_";
return false;
}
// Switch to the alternative decrypter and latch so that we cannot
// switch back.
decrypter_level_ = alternative_decrypter_level_;
alternative_decrypter_level_ = NUM_ENCRYPTION_LEVELS;
} else {
// Switch the alternative decrypter so that we use it first next time.
EncryptionLevel level = alternative_decrypter_level_;
alternative_decrypter_level_ = decrypter_level_;
decrypter_level_ = level;
}
}
}
if (!success) {
QUIC_DVLOG(1) << ENDPOINT << "DecryptPacket failed for: " << header;
return false;
}
return true;
}
size_t QuicFramer::GetIetfAckFrameSize(const QuicAckFrame& frame) {
// Type byte, largest_acked, and delay_time are straight-forward.
size_t ack_frame_size = kQuicFrameTypeSize;
QuicPacketNumber largest_acked = LargestAcked(frame);
ack_frame_size += QuicDataWriter::GetVarInt62Len(largest_acked.ToUint64());
uint64_t ack_delay_time_us;
ack_delay_time_us = frame.ack_delay_time.ToMicroseconds();
ack_delay_time_us = ack_delay_time_us >> local_ack_delay_exponent_;
ack_frame_size += QuicDataWriter::GetVarInt62Len(ack_delay_time_us);
if (frame.packets.Empty() || frame.packets.Max() != largest_acked) {
QUIC_BUG(quic_bug_10850_74) << "Malformed ack frame";
// ACK frame serialization will fail and connection will be closed.
return ack_frame_size;
}
// Ack block count.
ack_frame_size +=
QuicDataWriter::GetVarInt62Len(frame.packets.NumIntervals() - 1);
// First Ack range.
auto iter = frame.packets.rbegin();
ack_frame_size += QuicDataWriter::GetVarInt62Len(iter->Length() - 1);
QuicPacketNumber previous_smallest = iter->min();
++iter;
// Ack blocks.
for (; iter != frame.packets.rend(); ++iter) {
const uint64_t gap = previous_smallest - iter->max() - 1;
const uint64_t ack_range = iter->Length() - 1;
ack_frame_size += (QuicDataWriter::GetVarInt62Len(gap) +
QuicDataWriter::GetVarInt62Len(ack_range));
previous_smallest = iter->min();
}
// ECN counts.
if (frame.ecn_counters_populated &&
(frame.ect_0_count || frame.ect_1_count || frame.ecn_ce_count)) {
ack_frame_size += QuicDataWriter::GetVarInt62Len(frame.ect_0_count);
ack_frame_size += QuicDataWriter::GetVarInt62Len(frame.ect_1_count);
ack_frame_size += QuicDataWriter::GetVarInt62Len(frame.ecn_ce_count);
}
return ack_frame_size;
}
size_t QuicFramer::GetAckFrameSize(
const QuicAckFrame& ack,
QuicPacketNumberLength /*packet_number_length*/) {
QUICHE_DCHECK(!ack.packets.Empty());
size_t ack_size = 0;
if (VersionHasIetfQuicFrames(version_.transport_version)) {
return GetIetfAckFrameSize(ack);
}
AckFrameInfo ack_info = GetAckFrameInfo(ack);
QuicPacketNumberLength ack_block_length =
GetMinPacketNumberLength(QuicPacketNumber(ack_info.max_block_length));
ack_size = GetMinAckFrameSize(version_.transport_version, ack,
local_ack_delay_exponent_);
// First ack block length.
ack_size += ack_block_length;
if (ack_info.num_ack_blocks != 0) {
ack_size += kNumberOfAckBlocksSize;
ack_size += std::min(ack_info.num_ack_blocks, kMaxAckBlocks) *
(ack_block_length + PACKET_1BYTE_PACKET_NUMBER);
}
// Include timestamps.
if (process_timestamps_) {
ack_size += GetAckFrameTimeStampSize(ack);
}
return ack_size;
}
size_t QuicFramer::GetAckFrameTimeStampSize(const QuicAckFrame& ack) {
if (ack.received_packet_times.empty()) {
return 0;
}
return kQuicNumTimestampsLength + kQuicFirstTimestampLength +
(kQuicTimestampLength + kQuicTimestampPacketNumberGapLength) *
(ack.received_packet_times.size() - 1);
}
size_t QuicFramer::ComputeFrameLength(
const QuicFrame& frame,
bool last_frame_in_packet,
QuicPacketNumberLength packet_number_length) {
switch (frame.type) {
case STREAM_FRAME:
return GetMinStreamFrameSize(
version_.transport_version, frame.stream_frame.stream_id,
frame.stream_frame.offset, last_frame_in_packet,
frame.stream_frame.data_length) +
frame.stream_frame.data_length;
case CRYPTO_FRAME:
return GetMinCryptoFrameSize(frame.crypto_frame->offset,
frame.crypto_frame->data_length) +
frame.crypto_frame->data_length;
case ACK_FRAME: {
return GetAckFrameSize(*frame.ack_frame, packet_number_length);
}
case STOP_WAITING_FRAME:
return GetStopWaitingFrameSize(packet_number_length);
case MTU_DISCOVERY_FRAME:
// MTU discovery frames are serialized as ping frames.
return kQuicFrameTypeSize;
case MESSAGE_FRAME:
return GetMessageFrameSize(version_.transport_version,
last_frame_in_packet,
frame.message_frame->message_length);
case PADDING_FRAME:
QUICHE_DCHECK(false);
return 0;
default:
return GetRetransmittableControlFrameSize(version_.transport_version,
frame);
}
}
bool QuicFramer::AppendTypeByte(const QuicFrame& frame,
bool last_frame_in_packet,
QuicDataWriter* writer) {
if (VersionHasIetfQuicFrames(version_.transport_version)) {
return AppendIetfFrameType(frame, last_frame_in_packet, writer);
}
uint8_t type_byte = 0;
switch (frame.type) {
case STREAM_FRAME:
type_byte =
GetStreamFrameTypeByte(frame.stream_frame, last_frame_in_packet);
break;
case ACK_FRAME:
return true;
case MTU_DISCOVERY_FRAME:
type_byte = static_cast<uint8_t>(PING_FRAME);
break;
case NEW_CONNECTION_ID_FRAME:
set_detailed_error(
"Attempt to append NEW_CONNECTION_ID frame and not in IETF QUIC.");
return RaiseError(QUIC_INTERNAL_ERROR);
case RETIRE_CONNECTION_ID_FRAME:
set_detailed_error(
"Attempt to append RETIRE_CONNECTION_ID frame and not in IETF QUIC.");
return RaiseError(QUIC_INTERNAL_ERROR);
case NEW_TOKEN_FRAME:
set_detailed_error(
"Attempt to append NEW_TOKEN frame and not in IETF QUIC.");
return RaiseError(QUIC_INTERNAL_ERROR);
case MAX_STREAMS_FRAME:
set_detailed_error(
"Attempt to append MAX_STREAMS frame and not in IETF QUIC.");
return RaiseError(QUIC_INTERNAL_ERROR);
case STREAMS_BLOCKED_FRAME:
set_detailed_error(
"Attempt to append STREAMS_BLOCKED frame and not in IETF QUIC.");
return RaiseError(QUIC_INTERNAL_ERROR);
case PATH_RESPONSE_FRAME:
set_detailed_error(
"Attempt to append PATH_RESPONSE frame and not in IETF QUIC.");
return RaiseError(QUIC_INTERNAL_ERROR);
case PATH_CHALLENGE_FRAME:
set_detailed_error(
"Attempt to append PATH_CHALLENGE frame and not in IETF QUIC.");
return RaiseError(QUIC_INTERNAL_ERROR);
case STOP_SENDING_FRAME:
set_detailed_error(
"Attempt to append STOP_SENDING frame and not in IETF QUIC.");
return RaiseError(QUIC_INTERNAL_ERROR);
case MESSAGE_FRAME:
return true;
default:
type_byte = static_cast<uint8_t>(frame.type);
break;
}
return writer->WriteUInt8(type_byte);
}
bool QuicFramer::AppendIetfFrameType(const QuicFrame& frame,
bool last_frame_in_packet,
QuicDataWriter* writer) {
uint8_t type_byte = 0;
switch (frame.type) {
case PADDING_FRAME:
type_byte = IETF_PADDING;
break;
case RST_STREAM_FRAME:
type_byte = IETF_RST_STREAM;
break;
case CONNECTION_CLOSE_FRAME:
switch (frame.connection_close_frame->close_type) {
case IETF_QUIC_APPLICATION_CONNECTION_CLOSE:
type_byte = IETF_APPLICATION_CLOSE;
break;
case IETF_QUIC_TRANSPORT_CONNECTION_CLOSE:
type_byte = IETF_CONNECTION_CLOSE;
break;
default:
set_detailed_error(absl::StrCat(
"Invalid QuicConnectionCloseFrame type: ",
static_cast<int>(frame.connection_close_frame->close_type)));
return RaiseError(QUIC_INTERNAL_ERROR);
}
break;
case GOAWAY_FRAME:
set_detailed_error(
"Attempt to create non-IETF QUIC GOAWAY frame in IETF QUIC.");
return RaiseError(QUIC_INTERNAL_ERROR);
case WINDOW_UPDATE_FRAME:
// Depending on whether there is a stream ID or not, will be either a
// MAX_STREAM_DATA frame or a MAX_DATA frame.
if (frame.window_update_frame->stream_id ==
QuicUtils::GetInvalidStreamId(transport_version())) {
type_byte = IETF_MAX_DATA;
} else {
type_byte = IETF_MAX_STREAM_DATA;
}
break;
case BLOCKED_FRAME:
if (frame.blocked_frame->stream_id ==
QuicUtils::GetInvalidStreamId(transport_version())) {
type_byte = IETF_DATA_BLOCKED;
} else {
type_byte = IETF_STREAM_DATA_BLOCKED;
}
break;
case STOP_WAITING_FRAME:
set_detailed_error(
"Attempt to append type byte of STOP WAITING frame in IETF QUIC.");
return RaiseError(QUIC_INTERNAL_ERROR);
case PING_FRAME:
type_byte = IETF_PING;
break;
case STREAM_FRAME:
type_byte =
GetStreamFrameTypeByte(frame.stream_frame, last_frame_in_packet);
break;
case ACK_FRAME:
// Do nothing here, AppendIetfAckFrameAndTypeByte() will put the type byte
// in the buffer.
return true;
case MTU_DISCOVERY_FRAME:
// The path MTU discovery frame is encoded as a PING frame on the wire.
type_byte = IETF_PING;
break;
case NEW_CONNECTION_ID_FRAME:
type_byte = IETF_NEW_CONNECTION_ID;
break;
case RETIRE_CONNECTION_ID_FRAME:
type_byte = IETF_RETIRE_CONNECTION_ID;
break;
case NEW_TOKEN_FRAME:
type_byte = IETF_NEW_TOKEN;
break;
case MAX_STREAMS_FRAME:
if (frame.max_streams_frame.unidirectional) {
type_byte = IETF_MAX_STREAMS_UNIDIRECTIONAL;
} else {
type_byte = IETF_MAX_STREAMS_BIDIRECTIONAL;
}
break;
case STREAMS_BLOCKED_FRAME:
if (frame.streams_blocked_frame.unidirectional) {
type_byte = IETF_STREAMS_BLOCKED_UNIDIRECTIONAL;
} else {
type_byte = IETF_STREAMS_BLOCKED_BIDIRECTIONAL;
}
break;
case PATH_RESPONSE_FRAME:
type_byte = IETF_PATH_RESPONSE;
break;
case PATH_CHALLENGE_FRAME:
type_byte = IETF_PATH_CHALLENGE;
break;
case STOP_SENDING_FRAME:
type_byte = IETF_STOP_SENDING;
break;
case MESSAGE_FRAME:
return true;
case CRYPTO_FRAME:
type_byte = IETF_CRYPTO;
break;
case HANDSHAKE_DONE_FRAME:
type_byte = IETF_HANDSHAKE_DONE;
break;
case ACK_FREQUENCY_FRAME:
type_byte = IETF_ACK_FREQUENCY;
break;
default:
QUIC_BUG(quic_bug_10850_75)
<< "Attempt to generate a frame type for an unsupported value: "
<< frame.type;
return false;
}
return writer->WriteVarInt62(type_byte);
}
// static
bool QuicFramer::AppendPacketNumber(QuicPacketNumberLength packet_number_length,
QuicPacketNumber packet_number,
QuicDataWriter* writer) {
QUICHE_DCHECK(packet_number.IsInitialized());
if (!IsValidPacketNumberLength(packet_number_length)) {
QUIC_BUG(quic_bug_10850_76)
<< "Invalid packet_number_length: " << packet_number_length;
return false;
}
return writer->WriteBytesToUInt64(packet_number_length,
packet_number.ToUint64());
}
// static
bool QuicFramer::AppendStreamId(size_t stream_id_length,
QuicStreamId stream_id,
QuicDataWriter* writer) {
if (stream_id_length == 0 || stream_id_length > 4) {
QUIC_BUG(quic_bug_10850_77)
<< "Invalid stream_id_length: " << stream_id_length;
return false;
}
return writer->WriteBytesToUInt64(stream_id_length, stream_id);
}
// static
bool QuicFramer::AppendStreamOffset(size_t offset_length,
QuicStreamOffset offset,
QuicDataWriter* writer) {
if (offset_length == 1 || offset_length > 8) {
QUIC_BUG(quic_bug_10850_78)
<< "Invalid stream_offset_length: " << offset_length;
return false;
}
return writer->WriteBytesToUInt64(offset_length, offset);
}
// static
bool QuicFramer::AppendAckBlock(uint8_t gap,
QuicPacketNumberLength length_length,
uint64_t length,
QuicDataWriter* writer) {
if (length == 0) {
if (!IsValidPacketNumberLength(length_length)) {
QUIC_BUG(quic_bug_10850_79)
<< "Invalid packet_number_length: " << length_length;
return false;
}
return writer->WriteUInt8(gap) &&
writer->WriteBytesToUInt64(length_length, length);
}
return writer->WriteUInt8(gap) &&
AppendPacketNumber(length_length, QuicPacketNumber(length), writer);
}
bool QuicFramer::AppendStreamFrame(const QuicStreamFrame& frame,
bool no_stream_frame_length,
QuicDataWriter* writer) {
if (VersionHasIetfQuicFrames(version_.transport_version)) {
return AppendIetfStreamFrame(frame, no_stream_frame_length, writer);
}
if (!AppendStreamId(GetStreamIdSize(frame.stream_id), frame.stream_id,
writer)) {
QUIC_BUG(quic_bug_10850_80) << "Writing stream id size failed.";
return false;
}
if (!AppendStreamOffset(GetStreamOffsetSize(frame.offset), frame.offset,
writer)) {
QUIC_BUG(quic_bug_10850_81) << "Writing offset size failed.";
return false;
}
if (!no_stream_frame_length) {
static_assert(
std::numeric_limits<decltype(frame.data_length)>::max() <=
std::numeric_limits<uint16_t>::max(),
"If frame.data_length can hold more than a uint16_t than we need to "
"check that frame.data_length <= std::numeric_limits<uint16_t>::max()");
if (!writer->WriteUInt16(static_cast<uint16_t>(frame.data_length))) {
QUIC_BUG(quic_bug_10850_82) << "Writing stream frame length failed";
return false;
}
}
if (data_producer_ != nullptr) {
QUICHE_DCHECK_EQ(nullptr, frame.data_buffer);
if (frame.data_length == 0) {
return true;
}
if (data_producer_->WriteStreamData(frame.stream_id, frame.offset,
frame.data_length,
writer) != WRITE_SUCCESS) {
QUIC_BUG(quic_bug_10850_83) << "Writing frame data failed.";
return false;
}
return true;
}
if (!writer->WriteBytes(frame.data_buffer, frame.data_length)) {
QUIC_BUG(quic_bug_10850_84) << "Writing frame data failed.";
return false;
}
return true;
}
bool QuicFramer::AppendNewTokenFrame(const QuicNewTokenFrame& frame,
QuicDataWriter* writer) {
if (!writer->WriteVarInt62(static_cast<uint64_t>(frame.token.length()))) {
set_detailed_error("Writing token length failed.");
return false;
}
if (!writer->WriteBytes(frame.token.data(), frame.token.length())) {
set_detailed_error("Writing token buffer failed.");
return false;
}
return true;
}
bool QuicFramer::ProcessNewTokenFrame(QuicDataReader* reader,
QuicNewTokenFrame* frame) {
uint64_t length;
if (!reader->ReadVarInt62(&length)) {
set_detailed_error("Unable to read new token length.");
return false;
}
if (length > kMaxNewTokenTokenLength) {
set_detailed_error("Token length larger than maximum.");
return false;
}
// TODO(ianswett): Don't use absl::string_view as an intermediary.
absl::string_view data;
if (!reader->ReadStringPiece(&data, length)) {
set_detailed_error("Unable to read new token data.");
return false;
}
frame->token = std::string(data);
return true;
}
// Add a new ietf-format stream frame.
// Bits controlling whether there is a frame-length and frame-offset
// are in the QuicStreamFrame.
bool QuicFramer::AppendIetfStreamFrame(const QuicStreamFrame& frame,
bool last_frame_in_packet,
QuicDataWriter* writer) {
if (!writer->WriteVarInt62(static_cast<uint64_t>(frame.stream_id))) {
set_detailed_error("Writing stream id failed.");
return false;
}
if (frame.offset != 0) {
if (!writer->WriteVarInt62(static_cast<uint64_t>(frame.offset))) {
set_detailed_error("Writing data offset failed.");
return false;
}
}
if (!last_frame_in_packet) {
if (!writer->WriteVarInt62(frame.data_length)) {
set_detailed_error("Writing data length failed.");
return false;
}
}
if (frame.data_length == 0) {
return true;
}
if (data_producer_ == nullptr) {
if (!writer->WriteBytes(frame.data_buffer, frame.data_length)) {
set_detailed_error("Writing frame data failed.");
return false;
}
} else {
QUICHE_DCHECK_EQ(nullptr, frame.data_buffer);
if (data_producer_->WriteStreamData(frame.stream_id, frame.offset,
frame.data_length,
writer) != WRITE_SUCCESS) {
set_detailed_error("Writing frame data from producer failed.");
return false;
}
}
return true;
}
bool QuicFramer::AppendCryptoFrame(const QuicCryptoFrame& frame,
QuicDataWriter* writer) {
if (!writer->WriteVarInt62(static_cast<uint64_t>(frame.offset))) {
set_detailed_error("Writing data offset failed.");
return false;
}
if (!writer->WriteVarInt62(static_cast<uint64_t>(frame.data_length))) {
set_detailed_error("Writing data length failed.");
return false;
}
if (data_producer_ == nullptr) {
if (frame.data_buffer == nullptr ||
!writer->WriteBytes(frame.data_buffer, frame.data_length)) {
set_detailed_error("Writing frame data failed.");
return false;
}
} else {
QUICHE_DCHECK_EQ(nullptr, frame.data_buffer);
if (!data_producer_->WriteCryptoData(frame.level, frame.offset,
frame.data_length, writer)) {
return false;
}
}
return true;
}
bool QuicFramer::AppendAckFrequencyFrame(const QuicAckFrequencyFrame& frame,
QuicDataWriter* writer) {
if (!writer->WriteVarInt62(frame.sequence_number)) {
set_detailed_error("Writing sequence number failed.");
return false;
}
if (!writer->WriteVarInt62(frame.packet_tolerance)) {
set_detailed_error("Writing packet tolerance failed.");
return false;
}
if (!writer->WriteVarInt62(
static_cast<uint64_t>(frame.max_ack_delay.ToMicroseconds()))) {
set_detailed_error("Writing max_ack_delay_us failed.");
return false;
}
if (!writer->WriteUInt8(static_cast<uint8_t>(frame.ignore_order))) {
set_detailed_error("Writing ignore_order failed.");
return false;
}
return true;
}
void QuicFramer::set_version(const ParsedQuicVersion version) {
QUICHE_DCHECK(IsSupportedVersion(version))
<< ParsedQuicVersionToString(version);
version_ = version;
}
bool QuicFramer::AppendAckFrameAndTypeByte(const QuicAckFrame& frame,
QuicDataWriter* writer) {
if (VersionHasIetfQuicFrames(transport_version())) {
return AppendIetfAckFrameAndTypeByte(frame, writer);
}
const AckFrameInfo new_ack_info = GetAckFrameInfo(frame);
QuicPacketNumber largest_acked = LargestAcked(frame);
QuicPacketNumberLength largest_acked_length =
GetMinPacketNumberLength(largest_acked);
QuicPacketNumberLength ack_block_length =
GetMinPacketNumberLength(QuicPacketNumber(new_ack_info.max_block_length));
// Calculate available bytes for timestamps and ack blocks.
int32_t available_timestamp_and_ack_block_bytes =
writer->capacity() - writer->length() - ack_block_length -
GetMinAckFrameSize(version_.transport_version, frame,
local_ack_delay_exponent_) -
(new_ack_info.num_ack_blocks != 0 ? kNumberOfAckBlocksSize : 0);
QUICHE_DCHECK_LE(0, available_timestamp_and_ack_block_bytes);
uint8_t type_byte = 0;
SetBit(&type_byte, new_ack_info.num_ack_blocks != 0,
kQuicHasMultipleAckBlocksOffset);
SetBits(&type_byte, GetPacketNumberFlags(largest_acked_length),
kQuicSequenceNumberLengthNumBits, kLargestAckedOffset);
SetBits(&type_byte, GetPacketNumberFlags(ack_block_length),
kQuicSequenceNumberLengthNumBits, kActBlockLengthOffset);
type_byte |= kQuicFrameTypeAckMask;
if (!writer->WriteUInt8(type_byte)) {
return false;
}
size_t max_num_ack_blocks = available_timestamp_and_ack_block_bytes /
(ack_block_length + PACKET_1BYTE_PACKET_NUMBER);
// Number of ack blocks.
size_t num_ack_blocks =
std::min(new_ack_info.num_ack_blocks, max_num_ack_blocks);
if (num_ack_blocks > std::numeric_limits<uint8_t>::max()) {
num_ack_blocks = std::numeric_limits<uint8_t>::max();
}
// Largest acked.
if (!AppendPacketNumber(largest_acked_length, largest_acked, writer)) {
return false;
}
// Largest acked delta time.
uint64_t ack_delay_time_us = kUFloat16MaxValue;
if (!frame.ack_delay_time.IsInfinite()) {
QUICHE_DCHECK_LE(0u, frame.ack_delay_time.ToMicroseconds());
ack_delay_time_us = frame.ack_delay_time.ToMicroseconds();
}
if (!writer->WriteUFloat16(ack_delay_time_us)) {
return false;
}
if (num_ack_blocks > 0) {
if (!writer->WriteBytes(&num_ack_blocks, 1)) {
return false;
}
}
// First ack block length.
if (!AppendPacketNumber(ack_block_length,
QuicPacketNumber(new_ack_info.first_block_length),
writer)) {
return false;
}
// Ack blocks.
if (num_ack_blocks > 0) {
size_t num_ack_blocks_written = 0;
// Append, in descending order from the largest ACKed packet, a series of
// ACK blocks that represents the successfully acknoweldged packets. Each
// appended gap/block length represents a descending delta from the previous
// block. i.e.:
// |--- length ---|--- gap ---|--- length ---|--- gap ---|--- largest ---|
// For gaps larger than can be represented by a single encoded gap, a 0
// length gap of the maximum is used, i.e.:
// |--- length ---|--- gap ---|- 0 -|--- gap ---|--- largest ---|
auto itr = frame.packets.rbegin();
QuicPacketNumber previous_start = itr->min();
++itr;
for (;
itr != frame.packets.rend() && num_ack_blocks_written < num_ack_blocks;
previous_start = itr->min(), ++itr) {
const auto& interval = *itr;
const uint64_t total_gap = previous_start - interval.max();
const size_t num_encoded_gaps =
(total_gap + std::numeric_limits<uint8_t>::max() - 1) /
std::numeric_limits<uint8_t>::max();
// Append empty ACK blocks because the gap is longer than a single gap.
for (size_t i = 1;
i < num_encoded_gaps && num_ack_blocks_written < num_ack_blocks;
++i) {
if (!AppendAckBlock(std::numeric_limits<uint8_t>::max(),
ack_block_length, 0, writer)) {
return false;
}
++num_ack_blocks_written;
}
if (num_ack_blocks_written >= num_ack_blocks) {
if (QUIC_PREDICT_FALSE(num_ack_blocks_written != num_ack_blocks)) {
QUIC_BUG(quic_bug_10850_85)
<< "Wrote " << num_ack_blocks_written << ", expected to write "
<< num_ack_blocks;
}
break;
}
const uint8_t last_gap =
total_gap -
(num_encoded_gaps - 1) * std::numeric_limits<uint8_t>::max();
// Append the final ACK block with a non-empty size.
if (!AppendAckBlock(last_gap, ack_block_length, interval.Length(),
writer)) {
return false;
}
++num_ack_blocks_written;
}
QUICHE_DCHECK_EQ(num_ack_blocks, num_ack_blocks_written);
}
// Timestamps.
// If we don't process timestamps or if we don't have enough available space
// to append all the timestamps, don't append any of them.
if (process_timestamps_ && writer->capacity() - writer->length() >=
GetAckFrameTimeStampSize(frame)) {
if (!AppendTimestampsToAckFrame(frame, writer)) {
return false;
}
} else {
uint8_t num_received_packets = 0;
if (!writer->WriteBytes(&num_received_packets, 1)) {
return false;
}
}
return true;
}
bool QuicFramer::AppendTimestampsToAckFrame(const QuicAckFrame& frame,
QuicDataWriter* writer) {
QUICHE_DCHECK_GE(std::numeric_limits<uint8_t>::max(),
frame.received_packet_times.size());
// num_received_packets is only 1 byte.
if (frame.received_packet_times.size() >
std::numeric_limits<uint8_t>::max()) {
return false;
}
uint8_t num_received_packets = frame.received_packet_times.size();
if (!writer->WriteBytes(&num_received_packets, 1)) {
return false;
}
if (num_received_packets == 0) {
return true;
}
auto it = frame.received_packet_times.begin();
QuicPacketNumber packet_number = it->first;
uint64_t delta_from_largest_observed = LargestAcked(frame) - packet_number;
QUICHE_DCHECK_GE(std::numeric_limits<uint8_t>::max(),
delta_from_largest_observed);
if (delta_from_largest_observed > std::numeric_limits<uint8_t>::max()) {
return false;
}
if (!writer->WriteUInt8(delta_from_largest_observed)) {
return false;
}
// Use the lowest 4 bytes of the time delta from the creation_time_.
const uint64_t time_epoch_delta_us = UINT64_C(1) << 32;
uint32_t time_delta_us =
static_cast<uint32_t>((it->second - creation_time_).ToMicroseconds() &
(time_epoch_delta_us - 1));
if (!writer->WriteUInt32(time_delta_us)) {
return false;
}
QuicTime prev_time = it->second;
for (++it; it != frame.received_packet_times.end(); ++it) {
packet_number = it->first;
delta_from_largest_observed = LargestAcked(frame) - packet_number;
if (delta_from_largest_observed > std::numeric_limits<uint8_t>::max()) {
return false;
}
if (!writer->WriteUInt8(delta_from_largest_observed)) {
return false;
}
uint64_t frame_time_delta_us = (it->second - prev_time).ToMicroseconds();
prev_time = it->second;
if (!writer->WriteUFloat16(frame_time_delta_us)) {
return false;
}
}
return true;
}
bool QuicFramer::AppendStopWaitingFrame(const QuicPacketHeader& header,
const QuicStopWaitingFrame& frame,
QuicDataWriter* writer) {
QUICHE_DCHECK(!version_.HasIetfInvariantHeader());
QUICHE_DCHECK(frame.least_unacked.IsInitialized());
QUICHE_DCHECK_GE(header.packet_number, frame.least_unacked);
const uint64_t least_unacked_delta =
header.packet_number - frame.least_unacked;
const uint64_t length_shift = header.packet_number_length * 8;
if (least_unacked_delta >> length_shift > 0) {
QUIC_BUG(quic_bug_10850_86)
<< "packet_number_length " << header.packet_number_length
<< " is too small for least_unacked_delta: " << least_unacked_delta
<< " packet_number:" << header.packet_number
<< " least_unacked:" << frame.least_unacked
<< " version:" << version_.transport_version;
return false;
}
if (least_unacked_delta == 0) {
return writer->WriteBytesToUInt64(header.packet_number_length,
least_unacked_delta);
}
if (!AppendPacketNumber(header.packet_number_length,
QuicPacketNumber(least_unacked_delta), writer)) {
QUIC_BUG(quic_bug_10850_87)
<< " seq failed: " << header.packet_number_length;
return false;
}
return true;
}
bool QuicFramer::AppendIetfAckFrameAndTypeByte(const QuicAckFrame& frame,
QuicDataWriter* writer) {
uint8_t type = IETF_ACK;
uint64_t ecn_size = 0;
if (frame.ecn_counters_populated &&
(frame.ect_0_count || frame.ect_1_count || frame.ecn_ce_count)) {
// Change frame type to ACK_ECN if any ECN count is available.
type = IETF_ACK_ECN;
ecn_size = (QuicDataWriter::GetVarInt62Len(frame.ect_0_count) +
QuicDataWriter::GetVarInt62Len(frame.ect_1_count) +
QuicDataWriter::GetVarInt62Len(frame.ecn_ce_count));
}
if (!writer->WriteVarInt62(type)) {
set_detailed_error("No room for frame-type");
return false;
}
QuicPacketNumber largest_acked = LargestAcked(frame);
if (!writer->WriteVarInt62(largest_acked.ToUint64())) {
set_detailed_error("No room for largest-acked in ack frame");
return false;
}
uint64_t ack_delay_time_us = kVarInt62MaxValue;
if (!frame.ack_delay_time.IsInfinite()) {
QUICHE_DCHECK_LE(0u, frame.ack_delay_time.ToMicroseconds());
ack_delay_time_us = frame.ack_delay_time.ToMicroseconds();
ack_delay_time_us = ack_delay_time_us >> local_ack_delay_exponent_;
}
if (!writer->WriteVarInt62(ack_delay_time_us)) {
set_detailed_error("No room for ack-delay in ack frame");
return false;
}
if (frame.packets.Empty() || frame.packets.Max() != largest_acked) {
QUIC_BUG(quic_bug_10850_88) << "Malformed ack frame: " << frame;
set_detailed_error("Malformed ack frame");
return false;
}
// Latch ack_block_count for potential truncation.
const uint64_t ack_block_count = frame.packets.NumIntervals() - 1;
QuicDataWriter count_writer(QuicDataWriter::GetVarInt62Len(ack_block_count),
writer->data() + writer->length());
if (!writer->WriteVarInt62(ack_block_count)) {
set_detailed_error("No room for ack block count in ack frame");
return false;
}
auto iter = frame.packets.rbegin();
if (!writer->WriteVarInt62(iter->Length() - 1)) {
set_detailed_error("No room for first ack block in ack frame");
return false;
}
QuicPacketNumber previous_smallest = iter->min();
++iter;
// Append remaining ACK blocks.
uint64_t appended_ack_blocks = 0;
for (; iter != frame.packets.rend(); ++iter) {
const uint64_t gap = previous_smallest - iter->max() - 1;
const uint64_t ack_range = iter->Length() - 1;
if (writer->remaining() < ecn_size ||
writer->remaining() - ecn_size <
static_cast<size_t>(QuicDataWriter::GetVarInt62Len(gap) +
QuicDataWriter::GetVarInt62Len(ack_range))) {
// ACK range does not fit, truncate it.
break;
}
const bool success =
writer->WriteVarInt62(gap) && writer->WriteVarInt62(ack_range);
QUICHE_DCHECK(success);
previous_smallest = iter->min();
++appended_ack_blocks;
}
if (appended_ack_blocks < ack_block_count) {
// Truncation is needed, rewrite the ack block count.
if (QuicDataWriter::GetVarInt62Len(appended_ack_blocks) !=
QuicDataWriter::GetVarInt62Len(ack_block_count) ||
!count_writer.WriteVarInt62(appended_ack_blocks)) {
// This should never happen as ack_block_count is limited by
// max_ack_ranges_.
QUIC_BUG(quic_bug_10850_89)
<< "Ack frame truncation fails. ack_block_count: " << ack_block_count
<< ", appended count: " << appended_ack_blocks;
set_detailed_error("ACK frame truncation fails");
return false;
}
QUIC_DLOG(INFO) << ENDPOINT << "ACK ranges get truncated from "
<< ack_block_count << " to " << appended_ack_blocks;
}
if (type == IETF_ACK_ECN) {
// Encode the ECN counts.
if (!writer->WriteVarInt62(frame.ect_0_count)) {
set_detailed_error("No room for ect_0_count in ack frame");
return false;
}
if (!writer->WriteVarInt62(frame.ect_1_count)) {
set_detailed_error("No room for ect_1_count in ack frame");
return false;
}
if (!writer->WriteVarInt62(frame.ecn_ce_count)) {
set_detailed_error("No room for ecn_ce_count in ack frame");
return false;
}
}
return true;
}
bool QuicFramer::AppendRstStreamFrame(const QuicRstStreamFrame& frame,
QuicDataWriter* writer) {
if (VersionHasIetfQuicFrames(version_.transport_version)) {
return AppendIetfResetStreamFrame(frame, writer);
}
if (!writer->WriteUInt32(frame.stream_id)) {
return false;
}
if (!writer->WriteUInt64(frame.byte_offset)) {
return false;
}
uint32_t error_code = static_cast<uint32_t>(frame.error_code);
if (!writer->WriteUInt32(error_code)) {
return false;
}
return true;
}
bool QuicFramer::AppendConnectionCloseFrame(
const QuicConnectionCloseFrame& frame,
QuicDataWriter* writer) {
if (VersionHasIetfQuicFrames(version_.transport_version)) {
return AppendIetfConnectionCloseFrame(frame, writer);
}
uint32_t error_code = static_cast<uint32_t>(frame.wire_error_code);
if (!writer->WriteUInt32(error_code)) {
return false;
}
if (!writer->WriteStringPiece16(TruncateErrorString(frame.error_details))) {
return false;
}
return true;
}
bool QuicFramer::AppendGoAwayFrame(const QuicGoAwayFrame& frame,
QuicDataWriter* writer) {
uint32_t error_code = static_cast<uint32_t>(frame.error_code);
if (!writer->WriteUInt32(error_code)) {
return false;
}
uint32_t stream_id = static_cast<uint32_t>(frame.last_good_stream_id);
if (!writer->WriteUInt32(stream_id)) {
return false;
}
if (!writer->WriteStringPiece16(TruncateErrorString(frame.reason_phrase))) {
return false;
}
return true;
}
bool QuicFramer::AppendWindowUpdateFrame(const QuicWindowUpdateFrame& frame,
QuicDataWriter* writer) {
uint32_t stream_id = static_cast<uint32_t>(frame.stream_id);
if (!writer->WriteUInt32(stream_id)) {
return false;
}
if (!writer->WriteUInt64(frame.max_data)) {
return false;
}
return true;
}
bool QuicFramer::AppendBlockedFrame(const QuicBlockedFrame& frame,
QuicDataWriter* writer) {
if (VersionHasIetfQuicFrames(version_.transport_version)) {
if (frame.stream_id == QuicUtils::GetInvalidStreamId(transport_version())) {
return AppendDataBlockedFrame(frame, writer);
}
return AppendStreamDataBlockedFrame(frame, writer);
}
uint32_t stream_id = static_cast<uint32_t>(frame.stream_id);
if (!writer->WriteUInt32(stream_id)) {
return false;
}
return true;
}
bool QuicFramer::AppendPaddingFrame(const QuicPaddingFrame& frame,
QuicDataWriter* writer) {
if (frame.num_padding_bytes == 0) {
return false;
}
if (frame.num_padding_bytes < 0) {
QUIC_BUG_IF(quic_bug_12975_9, frame.num_padding_bytes != -1);
writer->WritePadding();
return true;
}
// Please note, num_padding_bytes includes type byte which has been written.
return writer->WritePaddingBytes(frame.num_padding_bytes - 1);
}
bool QuicFramer::AppendMessageFrameAndTypeByte(const QuicMessageFrame& frame,
bool last_frame_in_packet,
QuicDataWriter* writer) {
uint8_t type_byte;
if (VersionHasIetfQuicFrames(version_.transport_version)) {
type_byte = last_frame_in_packet ? IETF_EXTENSION_MESSAGE_NO_LENGTH_V99
: IETF_EXTENSION_MESSAGE_V99;
} else {
type_byte = last_frame_in_packet ? IETF_EXTENSION_MESSAGE_NO_LENGTH
: IETF_EXTENSION_MESSAGE;
}
if (!writer->WriteUInt8(type_byte)) {
return false;
}
if (!last_frame_in_packet && !writer->WriteVarInt62(frame.message_length)) {
return false;
}
for (const auto& slice : frame.message_data) {
if (!writer->WriteBytes(slice.data(), slice.length())) {
return false;
}
}
return true;
}
bool QuicFramer::RaiseError(QuicErrorCode error) {
QUIC_DLOG(INFO) << ENDPOINT << "Error: " << QuicErrorCodeToString(error)
<< " detail: " << detailed_error_;
set_error(error);
if (visitor_) {
visitor_->OnError(this);
}
return false;
}
bool QuicFramer::IsVersionNegotiation(
const QuicPacketHeader& header,
bool packet_has_ietf_packet_header) const {
if (!packet_has_ietf_packet_header &&
perspective_ == Perspective::IS_CLIENT) {
return header.version_flag;
}
if (header.form == IETF_QUIC_SHORT_HEADER_PACKET) {
return false;
}
return header.long_packet_type == VERSION_NEGOTIATION;
}
bool QuicFramer::AppendIetfConnectionCloseFrame(
const QuicConnectionCloseFrame& frame,
QuicDataWriter* writer) {
if (frame.close_type != IETF_QUIC_TRANSPORT_CONNECTION_CLOSE &&
frame.close_type != IETF_QUIC_APPLICATION_CONNECTION_CLOSE) {
QUIC_BUG(quic_bug_10850_90)
<< "Invalid close_type for writing IETF CONNECTION CLOSE.";
set_detailed_error("Invalid close_type for writing IETF CONNECTION CLOSE.");
return false;
}
if (!writer->WriteVarInt62(frame.wire_error_code)) {
set_detailed_error("Can not write connection close frame error code");
return false;
}
if (frame.close_type == IETF_QUIC_TRANSPORT_CONNECTION_CLOSE) {
// Write the frame-type of the frame causing the error only
// if it's a CONNECTION_CLOSE/Transport.
if (!writer->WriteVarInt62(frame.transport_close_frame_type)) {
set_detailed_error("Writing frame type failed.");
return false;
}
}
// There may be additional error information available in the extracted error
// code. Encode the error information in the reason phrase and serialize the
// result.
std::string final_error_string =
GenerateErrorString(frame.error_details, frame.quic_error_code);
if (!writer->WriteStringPieceVarInt62(
TruncateErrorString(final_error_string))) {
set_detailed_error("Can not write connection close phrase");
return false;
}
return true;
}
bool QuicFramer::ProcessIetfConnectionCloseFrame(
QuicDataReader* reader,
QuicConnectionCloseType type,
QuicConnectionCloseFrame* frame) {
frame->close_type = type;
uint64_t error_code;
if (!reader->ReadVarInt62(&error_code)) {
set_detailed_error("Unable to read connection close error code.");
return false;
}
frame->wire_error_code = error_code;
if (type == IETF_QUIC_TRANSPORT_CONNECTION_CLOSE) {
// The frame-type of the frame causing the error is present only
// if it's a CONNECTION_CLOSE/Transport.
if (!reader->ReadVarInt62(&frame->transport_close_frame_type)) {
set_detailed_error("Unable to read connection close frame type.");
return false;
}
}
uint64_t phrase_length;
if (!reader->ReadVarInt62(&phrase_length)) {
set_detailed_error("Unable to read connection close error details.");
return false;
}
absl::string_view phrase;
if (!reader->ReadStringPiece(&phrase, static_cast<size_t>(phrase_length))) {
set_detailed_error("Unable to read connection close error details.");
return false;
}
frame->error_details = std::string(phrase);
// The frame may have an extracted error code in it. Look for it and
// extract it. If it's not present, MaybeExtract will return
// QUIC_IETF_GQUIC_ERROR_MISSING.
MaybeExtractQuicErrorCode(frame);
return true;
}
// IETF Quic Path Challenge/Response frames.
bool QuicFramer::ProcessPathChallengeFrame(QuicDataReader* reader,
QuicPathChallengeFrame* frame) {
if (!reader->ReadBytes(frame->data_buffer.data(),
frame->data_buffer.size())) {
set_detailed_error("Can not read path challenge data.");
return false;
}
return true;
}
bool QuicFramer::ProcessPathResponseFrame(QuicDataReader* reader,
QuicPathResponseFrame* frame) {
if (!reader->ReadBytes(frame->data_buffer.data(),
frame->data_buffer.size())) {
set_detailed_error("Can not read path response data.");
return false;
}
return true;
}
bool QuicFramer::AppendPathChallengeFrame(const QuicPathChallengeFrame& frame,
QuicDataWriter* writer) {
if (!writer->WriteBytes(frame.data_buffer.data(), frame.data_buffer.size())) {
set_detailed_error("Writing Path Challenge data failed.");
return false;
}
return true;
}
bool QuicFramer::AppendPathResponseFrame(const QuicPathResponseFrame& frame,
QuicDataWriter* writer) {
if (!writer->WriteBytes(frame.data_buffer.data(), frame.data_buffer.size())) {
set_detailed_error("Writing Path Response data failed.");
return false;
}
return true;
}
// Add a new ietf-format stream reset frame.
// General format is
// stream id
// application error code
// final offset
bool QuicFramer::AppendIetfResetStreamFrame(const QuicRstStreamFrame& frame,
QuicDataWriter* writer) {
if (!writer->WriteVarInt62(static_cast<uint64_t>(frame.stream_id))) {
set_detailed_error("Writing reset-stream stream id failed.");
return false;
}
if (!writer->WriteVarInt62(static_cast<uint64_t>(frame.ietf_error_code))) {
set_detailed_error("Writing reset-stream error code failed.");
return false;
}
if (!writer->WriteVarInt62(static_cast<uint64_t>(frame.byte_offset))) {
set_detailed_error("Writing reset-stream final-offset failed.");
return false;
}
return true;
}
bool QuicFramer::ProcessIetfResetStreamFrame(QuicDataReader* reader,
QuicRstStreamFrame* frame) {
// Get Stream ID from frame. ReadVarIntStreamID returns false
// if either A) there is a read error or B) the resulting value of
// the Stream ID is larger than the maximum allowed value.
if (!ReadUint32FromVarint62(reader, IETF_RST_STREAM, &frame->stream_id)) {
return false;
}
if (!reader->ReadVarInt62(&frame->ietf_error_code)) {
set_detailed_error("Unable to read rst stream error code.");
return false;
}
frame->error_code =
IetfResetStreamErrorCodeToRstStreamErrorCode(frame->ietf_error_code);
if (!reader->ReadVarInt62(&frame->byte_offset)) {
set_detailed_error("Unable to read rst stream sent byte offset.");
return false;
}
return true;
}
bool QuicFramer::ProcessStopSendingFrame(
QuicDataReader* reader,
QuicStopSendingFrame* stop_sending_frame) {
if (!ReadUint32FromVarint62(reader, IETF_STOP_SENDING,
&stop_sending_frame->stream_id)) {
return false;
}
if (!reader->ReadVarInt62(&stop_sending_frame->ietf_error_code)) {
set_detailed_error("Unable to read stop sending application error code.");
return false;
}
stop_sending_frame->error_code = IetfResetStreamErrorCodeToRstStreamErrorCode(
stop_sending_frame->ietf_error_code);
return true;
}
bool QuicFramer::AppendStopSendingFrame(
const QuicStopSendingFrame& stop_sending_frame,
QuicDataWriter* writer) {
if (!writer->WriteVarInt62(stop_sending_frame.stream_id)) {
set_detailed_error("Can not write stop sending stream id");
return false;
}
if (!writer->WriteVarInt62(
static_cast<uint64_t>(stop_sending_frame.ietf_error_code))) {
set_detailed_error("Can not write application error code");
return false;
}
return true;
}
// Append/process IETF-Format MAX_DATA Frame
bool QuicFramer::AppendMaxDataFrame(const QuicWindowUpdateFrame& frame,
QuicDataWriter* writer) {
if (!writer->WriteVarInt62(frame.max_data)) {
set_detailed_error("Can not write MAX_DATA byte-offset");
return false;
}
return true;
}
bool QuicFramer::ProcessMaxDataFrame(QuicDataReader* reader,
QuicWindowUpdateFrame* frame) {
frame->stream_id = QuicUtils::GetInvalidStreamId(transport_version());
if (!reader->ReadVarInt62(&frame->max_data)) {
set_detailed_error("Can not read MAX_DATA byte-offset");
return false;
}
return true;
}
// Append/process IETF-Format MAX_STREAM_DATA Frame
bool QuicFramer::AppendMaxStreamDataFrame(const QuicWindowUpdateFrame& frame,
QuicDataWriter* writer) {
if (!writer->WriteVarInt62(frame.stream_id)) {
set_detailed_error("Can not write MAX_STREAM_DATA stream id");
return false;
}
if (!writer->WriteVarInt62(frame.max_data)) {
set_detailed_error("Can not write MAX_STREAM_DATA byte-offset");
return false;
}
return true;
}
bool QuicFramer::ProcessMaxStreamDataFrame(QuicDataReader* reader,
QuicWindowUpdateFrame* frame) {
if (!ReadUint32FromVarint62(reader, IETF_MAX_STREAM_DATA,
&frame->stream_id)) {
return false;
}
if (!reader->ReadVarInt62(&frame->max_data)) {
set_detailed_error("Can not read MAX_STREAM_DATA byte-count");
return false;
}
return true;
}
bool QuicFramer::AppendMaxStreamsFrame(const QuicMaxStreamsFrame& frame,
QuicDataWriter* writer) {
if (!writer->WriteVarInt62(frame.stream_count)) {
set_detailed_error("Can not write MAX_STREAMS stream count");
return false;
}
return true;
}
bool QuicFramer::ProcessMaxStreamsFrame(QuicDataReader* reader,
QuicMaxStreamsFrame* frame,
uint64_t frame_type) {
if (!ReadUint32FromVarint62(reader,
static_cast<QuicIetfFrameType>(frame_type),
&frame->stream_count)) {
return false;
}
frame->unidirectional = (frame_type == IETF_MAX_STREAMS_UNIDIRECTIONAL);
return true;
}
bool QuicFramer::AppendDataBlockedFrame(const QuicBlockedFrame& frame,
QuicDataWriter* writer) {
if (!writer->WriteVarInt62(frame.offset)) {
set_detailed_error("Can not write blocked offset.");
return false;
}
return true;
}
bool QuicFramer::ProcessDataBlockedFrame(QuicDataReader* reader,
QuicBlockedFrame* frame) {
// Indicates that it is a BLOCKED frame (as opposed to STREAM_BLOCKED).
frame->stream_id = QuicUtils::GetInvalidStreamId(transport_version());
if (!reader->ReadVarInt62(&frame->offset)) {
set_detailed_error("Can not read blocked offset.");
return false;
}
return true;
}
bool QuicFramer::AppendStreamDataBlockedFrame(const QuicBlockedFrame& frame,
QuicDataWriter* writer) {
if (!writer->WriteVarInt62(frame.stream_id)) {
set_detailed_error("Can not write stream blocked stream id.");
return false;
}
if (!writer->WriteVarInt62(frame.offset)) {
set_detailed_error("Can not write stream blocked offset.");
return false;
}
return true;
}
bool QuicFramer::ProcessStreamDataBlockedFrame(QuicDataReader* reader,
QuicBlockedFrame* frame) {
if (!ReadUint32FromVarint62(reader, IETF_STREAM_DATA_BLOCKED,
&frame->stream_id)) {
return false;
}
if (!reader->ReadVarInt62(&frame->offset)) {
set_detailed_error("Can not read stream blocked offset.");
return false;
}
return true;
}
bool QuicFramer::AppendStreamsBlockedFrame(const QuicStreamsBlockedFrame& frame,
QuicDataWriter* writer) {
if (!writer->WriteVarInt62(frame.stream_count)) {
set_detailed_error("Can not write STREAMS_BLOCKED stream count");
return false;
}
return true;
}
bool QuicFramer::ProcessStreamsBlockedFrame(QuicDataReader* reader,
QuicStreamsBlockedFrame* frame,
uint64_t frame_type) {
if (!ReadUint32FromVarint62(reader,
static_cast<QuicIetfFrameType>(frame_type),
&frame->stream_count)) {
return false;
}
if (frame->stream_count > QuicUtils::GetMaxStreamCount()) {
// If stream count is such that the resulting stream ID would exceed our
// implementation limit, generate an error.
set_detailed_error(
"STREAMS_BLOCKED stream count exceeds implementation limit.");
return false;
}
frame->unidirectional = (frame_type == IETF_STREAMS_BLOCKED_UNIDIRECTIONAL);
return true;
}
bool QuicFramer::AppendNewConnectionIdFrame(
const QuicNewConnectionIdFrame& frame,
QuicDataWriter* writer) {
if (!writer->WriteVarInt62(frame.sequence_number)) {
set_detailed_error("Can not write New Connection ID sequence number");
return false;
}
if (!writer->WriteVarInt62(frame.retire_prior_to)) {
set_detailed_error("Can not write New Connection ID retire_prior_to");
return false;
}
if (!writer->WriteLengthPrefixedConnectionId(frame.connection_id)) {
set_detailed_error("Can not write New Connection ID frame connection ID");
return false;
}
if (!writer->WriteBytes(
static_cast<const void*>(&frame.stateless_reset_token),
sizeof(frame.stateless_reset_token))) {
set_detailed_error("Can not write New Connection ID Reset Token");
return false;
}
return true;
}
bool QuicFramer::ProcessNewConnectionIdFrame(QuicDataReader* reader,
QuicNewConnectionIdFrame* frame) {
if (!reader->ReadVarInt62(&frame->sequence_number)) {
set_detailed_error(
"Unable to read new connection ID frame sequence number.");
return false;
}
if (!reader->ReadVarInt62(&frame->retire_prior_to)) {
set_detailed_error(
"Unable to read new connection ID frame retire_prior_to.");
return false;
}
if (frame->retire_prior_to > frame->sequence_number) {
set_detailed_error("Retire_prior_to > sequence_number.");
return false;
}
if (!reader->ReadLengthPrefixedConnectionId(&frame->connection_id)) {
set_detailed_error("Unable to read new connection ID frame connection id.");
return false;
}
if (!QuicUtils::IsConnectionIdValidForVersion(frame->connection_id,
transport_version())) {
set_detailed_error("Invalid new connection ID length for version.");
return false;
}
if (!reader->ReadBytes(&frame->stateless_reset_token,
sizeof(frame->stateless_reset_token))) {
set_detailed_error("Can not read new connection ID frame reset token.");
return false;
}
return true;
}
bool QuicFramer::AppendRetireConnectionIdFrame(
const QuicRetireConnectionIdFrame& frame,
QuicDataWriter* writer) {
if (!writer->WriteVarInt62(frame.sequence_number)) {
set_detailed_error("Can not write Retire Connection ID sequence number");
return false;
}
return true;
}
bool QuicFramer::ProcessRetireConnectionIdFrame(
QuicDataReader* reader,
QuicRetireConnectionIdFrame* frame) {
if (!reader->ReadVarInt62(&frame->sequence_number)) {
set_detailed_error(
"Unable to read retire connection ID frame sequence number.");
return false;
}
return true;
}
bool QuicFramer::ReadUint32FromVarint62(QuicDataReader* reader,
QuicIetfFrameType type,
QuicStreamId* id) {
uint64_t temp_uint64;
if (!reader->ReadVarInt62(&temp_uint64)) {
set_detailed_error("Unable to read " + QuicIetfFrameTypeString(type) +
" frame stream id/count.");
return false;
}
if (temp_uint64 > kMaxQuicStreamId) {
set_detailed_error("Stream id/count of " + QuicIetfFrameTypeString(type) +
"frame is too large.");
return false;
}
*id = static_cast<uint32_t>(temp_uint64);
return true;
}
uint8_t QuicFramer::GetStreamFrameTypeByte(const QuicStreamFrame& frame,
bool last_frame_in_packet) const {
if (VersionHasIetfQuicFrames(version_.transport_version)) {
return GetIetfStreamFrameTypeByte(frame, last_frame_in_packet);
}
uint8_t type_byte = 0;
// Fin bit.
type_byte |= frame.fin ? kQuicStreamFinMask : 0;
// Data Length bit.
type_byte <<= kQuicStreamDataLengthShift;
type_byte |= last_frame_in_packet ? 0 : kQuicStreamDataLengthMask;
// Offset 3 bits.
type_byte <<= kQuicStreamShift;
const size_t offset_len = GetStreamOffsetSize(frame.offset);
if (offset_len > 0) {
type_byte |= offset_len - 1;
}
// stream id 2 bits.
type_byte <<= kQuicStreamIdShift;
type_byte |= GetStreamIdSize(frame.stream_id) - 1;
type_byte |= kQuicFrameTypeStreamMask; // Set Stream Frame Type to 1.
return type_byte;
}
uint8_t QuicFramer::GetIetfStreamFrameTypeByte(
const QuicStreamFrame& frame,
bool last_frame_in_packet) const {
QUICHE_DCHECK(VersionHasIetfQuicFrames(version_.transport_version));
uint8_t type_byte = IETF_STREAM;
if (!last_frame_in_packet) {
type_byte |= IETF_STREAM_FRAME_LEN_BIT;
}
if (frame.offset != 0) {
type_byte |= IETF_STREAM_FRAME_OFF_BIT;
}
if (frame.fin) {
type_byte |= IETF_STREAM_FRAME_FIN_BIT;
}
return type_byte;
}
void QuicFramer::InferPacketHeaderTypeFromVersion() {
// This function should only be called when server connection negotiates the
// version.
QUICHE_DCHECK_EQ(perspective_, Perspective::IS_SERVER);
QUICHE_DCHECK(!infer_packet_header_type_from_version_);
infer_packet_header_type_from_version_ = true;
}
void QuicFramer::EnableMultiplePacketNumberSpacesSupport() {
if (supports_multiple_packet_number_spaces_) {
QUIC_BUG(quic_bug_10850_91)
<< "Multiple packet number spaces has already been enabled";
return;
}
if (largest_packet_number_.IsInitialized()) {
QUIC_BUG(quic_bug_10850_92)
<< "Try to enable multiple packet number spaces support after any "
"packet has been received.";
return;
}
supports_multiple_packet_number_spaces_ = true;
}
// static
QuicErrorCode QuicFramer::ParsePublicHeaderDispatcher(
const QuicEncryptedPacket& packet,
uint8_t expected_destination_connection_id_length,
PacketHeaderFormat* format,
QuicLongHeaderType* long_packet_type,
bool* version_present,
bool* has_length_prefix,
QuicVersionLabel* version_label,
ParsedQuicVersion* parsed_version,
QuicConnectionId* destination_connection_id,
QuicConnectionId* source_connection_id,
bool* retry_token_present,
absl::string_view* retry_token,
std::string* detailed_error) {
QuicDataReader reader(packet.data(), packet.length());
if (reader.IsDoneReading()) {
*detailed_error = "Unable to read first byte.";
return QUIC_INVALID_PACKET_HEADER;
}
const uint8_t first_byte = reader.PeekByte();
const bool ietf_format = QuicUtils::IsIetfPacketHeader(first_byte);
uint8_t unused_first_byte;
QuicVariableLengthIntegerLength retry_token_length_length;
QuicErrorCode error_code = ParsePublicHeader(
&reader, expected_destination_connection_id_length, ietf_format,
&unused_first_byte, format, version_present, has_length_prefix,
version_label, parsed_version, destination_connection_id,
source_connection_id, long_packet_type, &retry_token_length_length,
retry_token, detailed_error);
*retry_token_present =
retry_token_length_length != VARIABLE_LENGTH_INTEGER_LENGTH_0;
return error_code;
}
// static
QuicErrorCode QuicFramer::ParsePublicHeaderGoogleQuic(
QuicDataReader* reader,
uint8_t* first_byte,
PacketHeaderFormat* format,
bool* version_present,
QuicVersionLabel* version_label,
ParsedQuicVersion* parsed_version,
QuicConnectionId* destination_connection_id,
std::string* detailed_error) {
*format = GOOGLE_QUIC_PACKET;
*version_present = (*first_byte & PACKET_PUBLIC_FLAGS_VERSION) != 0;
uint8_t destination_connection_id_length = 0;
if ((*first_byte & PACKET_PUBLIC_FLAGS_8BYTE_CONNECTION_ID) != 0) {
destination_connection_id_length = kQuicDefaultConnectionIdLength;
}
if (!reader->ReadConnectionId(destination_connection_id,
destination_connection_id_length)) {
*detailed_error = "Unable to read ConnectionId.";
return QUIC_INVALID_PACKET_HEADER;
}
if (*version_present) {
if (!ProcessVersionLabel(reader, version_label)) {
*detailed_error = "Unable to read protocol version.";
return QUIC_INVALID_PACKET_HEADER;
}
*parsed_version = ParseQuicVersionLabel(*version_label);
}
return QUIC_NO_ERROR;
}
namespace {
const QuicVersionLabel kProxVersionLabel = 0x50524F58; // "PROX"
inline bool PacketHasLengthPrefixedConnectionIds(
const QuicDataReader& reader,
ParsedQuicVersion parsed_version,
QuicVersionLabel version_label,
uint8_t first_byte) {
if (parsed_version.IsKnown()) {
return parsed_version.HasLengthPrefixedConnectionIds();
}
// Received unsupported version, check known old unsupported versions.
if (QuicVersionLabelUses4BitConnectionIdLength(version_label)) {
return false;
}
// Received unknown version, check connection ID length byte.
if (reader.IsDoneReading()) {
// This check is required to safely peek the connection ID length byte.
return true;
}
const uint8_t connection_id_length_byte = reader.PeekByte();
// Check for packets produced by older versions of
// QuicFramer::WriteClientVersionNegotiationProbePacket
if (first_byte == 0xc0 && (connection_id_length_byte & 0x0f) == 0 &&
connection_id_length_byte >= 0x50 && version_label == 0xcabadaba) {
return false;
}
// Check for munged packets with version tag PROX.
if ((connection_id_length_byte & 0x0f) == 0 &&
connection_id_length_byte >= 0x20 && version_label == kProxVersionLabel) {
return false;
}
return true;
}
inline bool ParseLongHeaderConnectionIds(
QuicDataReader* reader,
bool has_length_prefix,
QuicVersionLabel version_label,
QuicConnectionId* destination_connection_id,
QuicConnectionId* source_connection_id,
std::string* detailed_error) {
if (has_length_prefix) {
if (!reader->ReadLengthPrefixedConnectionId(destination_connection_id)) {
*detailed_error = "Unable to read destination connection ID.";
return false;
}
if (!reader->ReadLengthPrefixedConnectionId(source_connection_id)) {
if (version_label == kProxVersionLabel) {
// The "PROX" version does not follow the length-prefixed invariants,
// and can therefore attempt to read a payload byte and interpret it
// as the source connection ID length, which could fail to parse.
// In that scenario we keep the source connection ID empty but mark
// parsing as successful.
return true;
}
*detailed_error = "Unable to read source connection ID.";
return false;
}
} else {
// Parse connection ID lengths.
uint8_t connection_id_lengths_byte;
if (!reader->ReadUInt8(&connection_id_lengths_byte)) {
*detailed_error = "Unable to read connection ID lengths.";
return false;
}
uint8_t destination_connection_id_length =
(connection_id_lengths_byte & kDestinationConnectionIdLengthMask) >> 4;
if (destination_connection_id_length != 0) {
destination_connection_id_length += kConnectionIdLengthAdjustment;
}
uint8_t source_connection_id_length =
connection_id_lengths_byte & kSourceConnectionIdLengthMask;
if (source_connection_id_length != 0) {
source_connection_id_length += kConnectionIdLengthAdjustment;
}
// Read destination connection ID.
if (!reader->ReadConnectionId(destination_connection_id,
destination_connection_id_length)) {
*detailed_error = "Unable to read destination connection ID.";
return false;
}
// Read source connection ID.
if (!reader->ReadConnectionId(source_connection_id,
source_connection_id_length)) {
*detailed_error = "Unable to read source connection ID.";
return false;
}
}
return true;
}
} // namespace
// static
QuicErrorCode QuicFramer::ParsePublicHeader(
QuicDataReader* reader,
uint8_t expected_destination_connection_id_length,
bool ietf_format,
uint8_t* first_byte,
PacketHeaderFormat* format,
bool* version_present,
bool* has_length_prefix,
QuicVersionLabel* version_label,
ParsedQuicVersion* parsed_version,
QuicConnectionId* destination_connection_id,
QuicConnectionId* source_connection_id,
QuicLongHeaderType* long_packet_type,
QuicVariableLengthIntegerLength* retry_token_length_length,
absl::string_view* retry_token,
std::string* detailed_error) {
*version_present = false;
*has_length_prefix = false;
*version_label = 0;
*parsed_version = UnsupportedQuicVersion();
*source_connection_id = EmptyQuicConnectionId();
*long_packet_type = INVALID_PACKET_TYPE;
*retry_token_length_length = VARIABLE_LENGTH_INTEGER_LENGTH_0;
*retry_token = absl::string_view();
*detailed_error = "";
if (!reader->ReadUInt8(first_byte)) {
*detailed_error = "Unable to read first byte.";
return QUIC_INVALID_PACKET_HEADER;
}
if (!ietf_format) {
return ParsePublicHeaderGoogleQuic(
reader, first_byte, format, version_present, version_label,
parsed_version, destination_connection_id, detailed_error);
}
*format = GetIetfPacketHeaderFormat(*first_byte);
if (*format == IETF_QUIC_SHORT_HEADER_PACKET) {
// Read destination connection ID using
// expected_destination_connection_id_length to determine its length.
if (!reader->ReadConnectionId(destination_connection_id,
expected_destination_connection_id_length)) {
*detailed_error = "Unable to read destination connection ID.";
return QUIC_INVALID_PACKET_HEADER;
}
return QUIC_NO_ERROR;
}
QUICHE_DCHECK_EQ(IETF_QUIC_LONG_HEADER_PACKET, *format);
*version_present = true;
if (!ProcessVersionLabel(reader, version_label)) {
*detailed_error = "Unable to read protocol version.";
return QUIC_INVALID_PACKET_HEADER;
}
if (*version_label == 0) {
*long_packet_type = VERSION_NEGOTIATION;
}
// Parse version.
*parsed_version = ParseQuicVersionLabel(*version_label);
// Figure out which IETF QUIC invariants this packet follows.
*has_length_prefix = PacketHasLengthPrefixedConnectionIds(
*reader, *parsed_version, *version_label, *first_byte);
// Parse connection IDs.
if (!ParseLongHeaderConnectionIds(reader, *has_length_prefix, *version_label,
destination_connection_id,
source_connection_id, detailed_error)) {
return QUIC_INVALID_PACKET_HEADER;
}
if (!parsed_version->IsKnown()) {
// Skip parsing of long packet type and retry token for unknown versions.
return QUIC_NO_ERROR;
}
// Parse long packet type.
if (!GetLongHeaderType(*first_byte, long_packet_type)) {
*detailed_error = "Unable to parse long packet type.";
return QUIC_INVALID_PACKET_HEADER;
}
if (!parsed_version->SupportsRetry() || *long_packet_type != INITIAL) {
// Retry token is only present on initial packets for some versions.
return QUIC_NO_ERROR;
}
*retry_token_length_length = reader->PeekVarInt62Length();
uint64_t retry_token_length;
if (!reader->ReadVarInt62(&retry_token_length)) {
*retry_token_length_length = VARIABLE_LENGTH_INTEGER_LENGTH_0;
*detailed_error = "Unable to read retry token length.";
return QUIC_INVALID_PACKET_HEADER;
}
if (!reader->ReadStringPiece(retry_token, retry_token_length)) {
*detailed_error = "Unable to read retry token.";
return QUIC_INVALID_PACKET_HEADER;
}
return QUIC_NO_ERROR;
}
// static
bool QuicFramer::WriteClientVersionNegotiationProbePacket(
char* packet_bytes,
QuicByteCount packet_length,
const char* destination_connection_id_bytes,
uint8_t destination_connection_id_length) {
if (packet_bytes == nullptr) {
QUIC_BUG(quic_bug_10850_93) << "Invalid packet_bytes";
return false;
}
if (packet_length < kMinPacketSizeForVersionNegotiation ||
packet_length > 65535) {
QUIC_BUG(quic_bug_10850_94) << "Invalid packet_length";
return false;
}
if (destination_connection_id_length > kQuicMaxConnectionId4BitLength ||
destination_connection_id_length < kQuicDefaultConnectionIdLength) {
QUIC_BUG(quic_bug_10850_95) << "Invalid connection_id_length";
return false;
}
// clang-format off
const unsigned char packet_start_bytes[] = {
// IETF long header with fixed bit set, type initial, all-0 encrypted bits.
0xc0,
// Version, part of the IETF space reserved for negotiation.
// This intentionally differs from QuicVersionReservedForNegotiation()
// to allow differentiating them over the wire.
0xca, 0xba, 0xda, 0xda,
};
// clang-format on
static_assert(sizeof(packet_start_bytes) == 5, "bad packet_start_bytes size");
QuicDataWriter writer(packet_length, packet_bytes);
if (!writer.WriteBytes(packet_start_bytes, sizeof(packet_start_bytes))) {
QUIC_BUG(quic_bug_10850_96) << "Failed to write packet start";
return false;
}
QuicConnectionId destination_connection_id(destination_connection_id_bytes,
destination_connection_id_length);
if (!AppendIetfConnectionIds(
/*version_flag=*/true, /*use_length_prefix=*/true,
destination_connection_id, EmptyQuicConnectionId(), &writer)) {
QUIC_BUG(quic_bug_10850_97) << "Failed to write connection IDs";
return false;
}
// Add 8 bytes of zeroes followed by 8 bytes of ones to ensure that this does
// not parse with any known version. The zeroes make sure that packet numbers,
// retry token lengths and payload lengths are parsed as zero, and if the
// zeroes are treated as padding frames, 0xff is known to not parse as a
// valid frame type.
if (!writer.WriteUInt64(0) ||
!writer.WriteUInt64(std::numeric_limits<uint64_t>::max())) {
QUIC_BUG(quic_bug_10850_98) << "Failed to write 18 bytes";
return false;
}
// Make sure the polite greeting below is padded to a 16-byte boundary to
// make it easier to read in tcpdump.
while (writer.length() % 16 != 0) {
if (!writer.WriteUInt8(0)) {
QUIC_BUG(quic_bug_10850_99) << "Failed to write padding byte";
return false;
}
}
// Add a polite greeting in case a human sees this in tcpdump.
static const char polite_greeting[] =
"This packet only exists to trigger IETF QUIC version negotiation. "
"Please respond with a Version Negotiation packet indicating what "
"versions you support. Thank you and have a nice day.";
if (!writer.WriteBytes(polite_greeting, sizeof(polite_greeting))) {
QUIC_BUG(quic_bug_10850_100) << "Failed to write polite greeting";
return false;
}
// Fill the rest of the packet with zeroes.
writer.WritePadding();
QUICHE_DCHECK_EQ(0u, writer.remaining());
return true;
}
// static
bool QuicFramer::ParseServerVersionNegotiationProbeResponse(
const char* packet_bytes,
QuicByteCount packet_length,
char* source_connection_id_bytes,
uint8_t* source_connection_id_length_out,
std::string* detailed_error) {
if (detailed_error == nullptr) {
QUIC_BUG(quic_bug_10850_101) << "Invalid error_details";
return false;
}
*detailed_error = "";
if (packet_bytes == nullptr) {
*detailed_error = "Invalid packet_bytes";
return false;
}
if (packet_length < 6) {
*detailed_error = "Invalid packet_length";
return false;
}
if (source_connection_id_bytes == nullptr) {
*detailed_error = "Invalid source_connection_id_bytes";
return false;
}
if (source_connection_id_length_out == nullptr) {
*detailed_error = "Invalid source_connection_id_length_out";
return false;
}
QuicDataReader reader(packet_bytes, packet_length);
uint8_t type_byte = 0;
if (!reader.ReadUInt8(&type_byte)) {
*detailed_error = "Failed to read type byte";
return false;
}
if ((type_byte & 0x80) == 0) {
*detailed_error = "Packet does not have long header";
return false;
}
uint32_t version = 0;
if (!reader.ReadUInt32(&version)) {
*detailed_error = "Failed to read version";
return false;
}
if (version != 0) {
*detailed_error = "Packet is not a version negotiation packet";
return false;
}
QuicConnectionId destination_connection_id, source_connection_id;
if (!reader.ReadLengthPrefixedConnectionId(&destination_connection_id)) {
*detailed_error = "Failed to read destination connection ID";
return false;
}
if (!reader.ReadLengthPrefixedConnectionId(&source_connection_id)) {
*detailed_error = "Failed to read source connection ID";
return false;
}
if (destination_connection_id.length() != 0) {
*detailed_error = "Received unexpected destination connection ID length";
return false;
}
if (*source_connection_id_length_out < source_connection_id.length()) {
*detailed_error =
absl::StrCat("*source_connection_id_length_out too small ",
static_cast<int>(*source_connection_id_length_out), " < ",
static_cast<int>(source_connection_id.length()));
return false;
}
memcpy(source_connection_id_bytes, source_connection_id.data(),
source_connection_id.length());
*source_connection_id_length_out = source_connection_id.length();
return true;
}
// Look for and parse the error code from the "<quic_error_code>:" text that
// may be present at the start of the CONNECTION_CLOSE error details string.
// This text, inserted by the peer if it's using Google's QUIC implementation,
// contains additional error information that narrows down the exact error. If
// the string is not found, or is not properly formed, it returns
// ErrorCode::QUIC_IETF_GQUIC_ERROR_MISSING
void MaybeExtractQuicErrorCode(QuicConnectionCloseFrame* frame) {
std::vector<absl::string_view> ed = absl::StrSplit(frame->error_details, ':');
uint64_t extracted_error_code;
if (ed.size() < 2 || !quiche::QuicheTextUtils::IsAllDigits(ed[0]) ||
!absl::SimpleAtoi(ed[0], &extracted_error_code)) {
if (frame->close_type == IETF_QUIC_TRANSPORT_CONNECTION_CLOSE &&
frame->wire_error_code == NO_IETF_QUIC_ERROR) {
frame->quic_error_code = QUIC_NO_ERROR;
} else {
frame->quic_error_code = QUIC_IETF_GQUIC_ERROR_MISSING;
}
return;
}
// Return the error code (numeric) and the error details string without the
// error code prefix. Note that Split returns everything up to, but not
// including, the split character, so the length of ed[0] is just the number
// of digits in the error number. In removing the prefix, 1 is added to the
// length to account for the :
absl::string_view x = absl::string_view(frame->error_details);
x.remove_prefix(ed[0].length() + 1);
frame->error_details = std::string(x);
frame->quic_error_code = static_cast<QuicErrorCode>(extracted_error_code);
}
#undef ENDPOINT // undef for jumbo builds
} // namespace quic