// 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.
#ifndef NET_QUIC_QUIC_FRAMER_H_
#define NET_QUIC_QUIC_FRAMER_H_
#include <vector>
#include "base/basictypes.h"
#include "base/logging.h"
#include "base/memory/scoped_ptr.h"
#include "base/strings/string_piece.h"
#include "net/base/net_export.h"
#include "net/quic/quic_protocol.h"
namespace net {
namespace test {
class QuicFramerPeer;
} // namespace test
class QuicDataReader;
class QuicDataWriter;
class QuicDecrypter;
class QuicEncrypter;
class QuicFramer;
// Number of bytes reserved for the frame type preceding each frame.
const size_t kQuicFrameTypeSize = 1;
// Number of bytes reserved for error code.
const size_t kQuicErrorCodeSize = 4;
// Number of bytes reserved to denote the length of error details field.
const size_t kQuicErrorDetailsLengthSize = 2;
// Maximum number of bytes reserved for stream id.
const size_t kQuicMaxStreamIdSize = 4;
// Maximum number of bytes reserved for byte offset in stream frame.
const size_t kQuicMaxStreamOffsetSize = 8;
// Number of bytes reserved to store payload length in stream frame.
const size_t kQuicStreamPayloadLengthSize = 2;
// Size in bytes of the entropy hash sent in ack frames.
const size_t kQuicEntropyHashSize = 1;
// Size in bytes reserved for the delta time of the largest observed
// sequence number in ack frames.
const size_t kQuicDeltaTimeLargestObservedSize = 2;
// Size in bytes reserved for the number of missing packets in ack frames.
const size_t kNumberOfMissingPacketsSize = 1;
// Size in bytes reserved for the number of revived packets in ack frames.
const size_t kNumberOfRevivedPacketsSize = 1;
// This class receives callbacks from the framer when packets
// are processed.
class NET_EXPORT_PRIVATE QuicFramerVisitorInterface {
public:
virtual ~QuicFramerVisitorInterface() {}
// Called if an error is detected in the QUIC protocol.
virtual void OnError(QuicFramer* framer) = 0;
// Called only when |is_server_| is true and the the framer gets a packet with
// version flag true and the version on the packet doesn't match
// |quic_version_|. The visitor should return true after it updates the
// version of the |framer_| to |received_version| or false to stop processing
// this packet.
virtual bool OnProtocolVersionMismatch(QuicVersion received_version) = 0;
// Called when a new packet has been received, before it
// has been validated or processed.
virtual void OnPacket() = 0;
// Called when a public reset packet has been parsed but has not yet
// been validated.
virtual void OnPublicResetPacket(
const QuicPublicResetPacket& packet) = 0;
// Called only when |is_server_| is false and a version negotiation packet has
// been parsed.
virtual void OnVersionNegotiationPacket(
const QuicVersionNegotiationPacket& packet) = 0;
// Called when a lost packet has been recovered via FEC,
// before it has been processed.
virtual void OnRevivedPacket() = 0;
// Called when the public header has been parsed, but has not been
// authenticated. If it returns false, framing for this packet will cease.
virtual bool OnUnauthenticatedPublicHeader(
const QuicPacketPublicHeader& header) = 0;
// Called when the unauthenticated portion of the header has been parsed.
// If OnUnauthenticatedHeader returns false, framing for this packet will
// cease.
virtual bool OnUnauthenticatedHeader(const QuicPacketHeader& header) = 0;
// Called when the complete header of a packet had been parsed.
// If OnPacketHeader returns false, framing for this packet will cease.
virtual bool OnPacketHeader(const QuicPacketHeader& header) = 0;
// Called when a data packet is parsed that is part of an FEC group.
// |payload| is the non-encrypted FEC protected payload of the packet.
virtual void OnFecProtectedPayload(base::StringPiece payload) = 0;
// Called when a StreamFrame has been parsed.
virtual bool OnStreamFrame(const QuicStreamFrame& frame) = 0;
// Called when a AckFrame has been parsed. If OnAckFrame returns false,
// the framer will stop parsing the current packet.
virtual bool OnAckFrame(const QuicAckFrame& frame) = 0;
// Called when a CongestionFeedbackFrame has been parsed.
virtual bool OnCongestionFeedbackFrame(
const QuicCongestionFeedbackFrame& frame) = 0;
// Called when a StopWaitingFrame has been parsed.
virtual bool OnStopWaitingFrame(const QuicStopWaitingFrame& frame) = 0;
// Called when a RstStreamFrame has been parsed.
virtual bool OnRstStreamFrame(const QuicRstStreamFrame& frame) = 0;
// Called when a ConnectionCloseFrame has been parsed.
virtual bool OnConnectionCloseFrame(
const QuicConnectionCloseFrame& frame) = 0;
// Called when a GoAwayFrame has been parsed.
virtual bool OnGoAwayFrame(const QuicGoAwayFrame& frame) = 0;
// Called when a WindowUpdateFrame has been parsed.
virtual bool OnWindowUpdateFrame(const QuicWindowUpdateFrame& frame) = 0;
// Called when a BlockedFrame has been parsed.
virtual bool OnBlockedFrame(const QuicBlockedFrame& frame) = 0;
// Called when FEC data has been parsed.
virtual void OnFecData(const QuicFecData& fec) = 0;
// Called when a packet has been completely processed.
virtual void OnPacketComplete() = 0;
};
class NET_EXPORT_PRIVATE QuicFecBuilderInterface {
public:
virtual ~QuicFecBuilderInterface() {}
// Called when a data packet is constructed that is part of an FEC group.
// |payload| is the non-encrypted FEC protected payload of the packet.
virtual void OnBuiltFecProtectedPayload(const QuicPacketHeader& header,
base::StringPiece payload) = 0;
};
// This class calculates the received entropy of the ack packet being
// framed, should it get truncated.
class NET_EXPORT_PRIVATE QuicReceivedEntropyHashCalculatorInterface {
public:
virtual ~QuicReceivedEntropyHashCalculatorInterface() {}
// When an ack frame gets truncated while being framed the received
// entropy of the ack frame needs to be calculated since the some of the
// missing packets are not added and the largest observed might be lowered.
// This should return the received entropy hash of the packets received up to
// and including |sequence_number|.
virtual QuicPacketEntropyHash EntropyHash(
QuicPacketSequenceNumber sequence_number) const = 0;
};
// Class for parsing and constructing QUIC packets. It has a
// QuicFramerVisitorInterface that is called when packets are parsed.
// It also has a QuicFecBuilder that is called when packets are constructed
// in order to generate FEC data for subsequently building FEC packets.
class NET_EXPORT_PRIVATE QuicFramer {
public:
// Constructs a new framer that installs a kNULL QuicEncrypter and
// QuicDecrypter for level ENCRYPTION_NONE. |supported_versions| specifies the
// list of supported QUIC versions. |quic_version_| is set to the maximum
// version in |supported_versions|.
QuicFramer(const QuicVersionVector& supported_versions,
QuicTime creation_time,
bool is_server);
virtual ~QuicFramer();
// Returns true if |version| is a supported protocol version.
bool IsSupportedVersion(const QuicVersion version) const;
// Set callbacks to be called from the framer. A visitor must be set, or
// else the framer will likely crash. It is acceptable for the visitor
// to do nothing. If this is called multiple times, only the last visitor
// will be used.
void set_visitor(QuicFramerVisitorInterface* visitor) {
visitor_ = visitor;
}
// Set a builder to be called from the framer when building FEC protected
// packets. If this is called multiple times, only the last builder
// will be used. The builder need not be set.
void set_fec_builder(QuicFecBuilderInterface* builder) {
fec_builder_ = builder;
}
const QuicVersionVector& supported_versions() const {
return supported_versions_;
}
QuicVersion version() const {
return quic_version_;
}
void set_version(const QuicVersion version);
// Does not DCHECK for supported version. Used by tests to set unsupported
// version to trigger version negotiation.
void set_version_for_tests(const QuicVersion version) {
quic_version_ = version;
}
// Set entropy calculator to be called from the framer when it needs the
// entropy of a truncated ack frame. An entropy calculator must be set or else
// the framer will likely crash. If this is called multiple times, only the
// last calculator will be used.
void set_received_entropy_calculator(
QuicReceivedEntropyHashCalculatorInterface* entropy_calculator) {
entropy_calculator_ = entropy_calculator;
}
QuicErrorCode error() const {
return error_;
}
// Pass a UDP packet into the framer for parsing.
// Return true if the packet was processed succesfully. |packet| must be a
// single, complete UDP packet (not a frame of a packet). This packet
// might be null padded past the end of the payload, which will be correctly
// ignored.
bool ProcessPacket(const QuicEncryptedPacket& packet);
// Pass a data packet that was revived from FEC data into the framer
// for parsing.
// Return true if the packet was processed succesfully. |payload| must be
// the complete DECRYPTED payload of the revived packet.
bool ProcessRevivedPacket(QuicPacketHeader* header,
base::StringPiece payload);
// Largest size in bytes of all stream frame fields without the payload.
static size_t GetMinStreamFrameSize(QuicVersion version,
QuicStreamId stream_id,
QuicStreamOffset offset,
bool last_frame_in_packet,
InFecGroup is_in_fec_group);
// Size in bytes of all ack frame fields without the missing packets.
static size_t GetMinAckFrameSize(
QuicVersion version,
QuicSequenceNumberLength sequence_number_length,
QuicSequenceNumberLength largest_observed_length);
// Size in bytes of a stop waiting frame.
static size_t GetStopWaitingFrameSize(
QuicSequenceNumberLength sequence_number_length);
// Size in bytes of all reset stream frame without the error details.
static size_t GetMinRstStreamFrameSize(QuicVersion quic_version);
// Size in bytes of all connection close frame fields without the error
// details and the missing packets from the enclosed ack frame.
static size_t GetMinConnectionCloseFrameSize();
// Size in bytes of all GoAway frame fields without the reason phrase.
static size_t GetMinGoAwayFrameSize();
// Size in bytes of all WindowUpdate frame fields.
static size_t GetWindowUpdateFrameSize();
// Size in bytes of all Blocked frame fields.
static size_t GetBlockedFrameSize();
// Size in bytes required to serialize the stream id.
static size_t GetStreamIdSize(QuicStreamId stream_id);
// Size in bytes required to serialize the stream offset.
static size_t GetStreamOffsetSize(QuicStreamOffset offset);
// Size in bytes required for a serialized version negotiation packet
static size_t GetVersionNegotiationPacketSize(size_t number_versions);
// Returns the number of bytes added to the packet for the specified frame,
// and 0 if the frame doesn't fit. Includes the header size for the first
// frame.
size_t GetSerializedFrameLength(
const QuicFrame& frame,
size_t free_bytes,
bool first_frame_in_packet,
bool last_frame_in_packet,
InFecGroup is_in_fec_group,
QuicSequenceNumberLength sequence_number_length);
// Returns the associated data from the encrypted packet |encrypted| as a
// stringpiece.
static base::StringPiece GetAssociatedDataFromEncryptedPacket(
const QuicEncryptedPacket& encrypted,
QuicConnectionIdLength connection_id_length,
bool includes_version,
QuicSequenceNumberLength sequence_number_length);
// Returns a SerializedPacket whose |packet| member is owned by the caller,
// and is populated with the fields in |header| and |frames|, or is NULL if
// the packet could not be created.
// TODO(ianswett): Used for testing only.
SerializedPacket BuildUnsizedDataPacket(const QuicPacketHeader& header,
const QuicFrames& frames);
// Returns a SerializedPacket whose |packet| member is owned by the caller,
// is created from the first |num_frames| frames, or is NULL if the packet
// could not be created. The packet must be of size |packet_size|.
SerializedPacket BuildDataPacket(const QuicPacketHeader& header,
const QuicFrames& frames,
size_t packet_size);
// Returns a SerializedPacket whose |packet| member is owned by the caller,
// and is populated with the fields in |header| and |fec|, or is NULL if the
// packet could not be created.
SerializedPacket BuildFecPacket(const QuicPacketHeader& header,
const QuicFecData& fec);
// Returns a new public reset packet, owned by the caller.
static QuicEncryptedPacket* BuildPublicResetPacket(
const QuicPublicResetPacket& packet);
QuicEncryptedPacket* BuildVersionNegotiationPacket(
const QuicPacketPublicHeader& header,
const QuicVersionVector& supported_versions);
// SetDecrypter sets the primary decrypter, replacing any that already exists,
// and takes ownership. If an alternative decrypter is in place then the
// function DCHECKs. This is intended for cases where one knows that future
// packets will be using the new decrypter and the previous decrypter is not
// obsolete.
void SetDecrypter(QuicDecrypter* decrypter);
// SetAlternativeDecrypter sets a decrypter that may be used to decrypt
// future packets and takes ownership of it. If |latch_once_used| is true,
// then the first time that the decrypter is successful it will replace the
// primary decrypter. Otherwise both decrypters will remain active and the
// primary decrypter will be the one last used.
void SetAlternativeDecrypter(QuicDecrypter* decrypter,
bool latch_once_used);
const QuicDecrypter* decrypter() const;
const QuicDecrypter* alternative_decrypter() const;
// Changes the encrypter used for level |level| to |encrypter|. The function
// takes ownership of |encrypter|.
void SetEncrypter(EncryptionLevel level, QuicEncrypter* encrypter);
const QuicEncrypter* encrypter(EncryptionLevel level) const;
// SwapCryptersForTest exchanges the state of the crypters with |other|. To
// be used in tests only.
void SwapCryptersForTest(QuicFramer* other);
// Returns a new encrypted packet, owned by the caller.
QuicEncryptedPacket* EncryptPacket(EncryptionLevel level,
QuicPacketSequenceNumber sequence_number,
const QuicPacket& packet);
// Returns the maximum length of plaintext that can be encrypted
// to ciphertext no larger than |ciphertext_size|.
size_t GetMaxPlaintextSize(size_t ciphertext_size);
const std::string& detailed_error() { return detailed_error_; }
// The minimum sequence number length required to represent |sequence_number|.
static QuicSequenceNumberLength GetMinSequenceNumberLength(
QuicPacketSequenceNumber sequence_number);
void SetSupportedVersions(const QuicVersionVector& versions) {
supported_versions_ = versions;
quic_version_ = versions[0];
}
void set_validate_flags(bool value) { validate_flags_ = value; }
private:
friend class test::QuicFramerPeer;
typedef std::map<QuicPacketSequenceNumber, uint8> NackRangeMap;
struct AckFrameInfo {
AckFrameInfo();
~AckFrameInfo();
// The maximum delta between ranges.
QuicPacketSequenceNumber max_delta;
// Nack ranges starting with start sequence numbers and lengths.
NackRangeMap nack_ranges;
};
QuicPacketEntropyHash GetPacketEntropyHash(
const QuicPacketHeader& header) const;
bool ProcessDataPacket(const QuicPacketPublicHeader& public_header,
const QuicEncryptedPacket& packet);
bool ProcessPublicResetPacket(const QuicPacketPublicHeader& public_header);
bool ProcessVersionNegotiationPacket(QuicPacketPublicHeader* public_header);
bool ProcessPublicHeader(QuicPacketPublicHeader* header);
bool ProcessPacketHeader(QuicPacketHeader* header,
const QuicEncryptedPacket& packet);
bool ProcessPacketSequenceNumber(
QuicSequenceNumberLength sequence_number_length,
QuicPacketSequenceNumber* sequence_number);
bool ProcessFrameData(const QuicPacketHeader& header);
bool ProcessStreamFrame(uint8 frame_type, QuicStreamFrame* frame);
bool ProcessAckFrame(const QuicPacketHeader& header,
uint8 frame_type,
QuicAckFrame* frame);
bool ProcessReceivedInfo(uint8 frame_type, ReceivedPacketInfo* received_info);
bool ProcessStopWaitingFrame(const QuicPacketHeader& public_header,
QuicStopWaitingFrame* stop_waiting);
bool ProcessQuicCongestionFeedbackFrame(
QuicCongestionFeedbackFrame* congestion_feedback);
bool ProcessRstStreamFrame(QuicRstStreamFrame* frame);
bool ProcessConnectionCloseFrame(QuicConnectionCloseFrame* frame);
bool ProcessGoAwayFrame(QuicGoAwayFrame* frame);
bool ProcessWindowUpdateFrame(QuicWindowUpdateFrame* frame);
bool ProcessBlockedFrame(QuicBlockedFrame* frame);
bool DecryptPayload(const QuicPacketHeader& header,
const QuicEncryptedPacket& packet);
// Returns the full packet sequence number from the truncated
// wire format version and the last seen packet sequence number.
QuicPacketSequenceNumber CalculatePacketSequenceNumberFromWire(
QuicSequenceNumberLength sequence_number_length,
QuicPacketSequenceNumber packet_sequence_number) const;
// Computes the wire size in bytes of the |ack| frame, assuming no truncation.
size_t GetAckFrameSize(const QuicAckFrame& ack,
QuicSequenceNumberLength sequence_number_length);
// Computes the wire size in bytes of the payload of |frame|.
size_t ComputeFrameLength(const QuicFrame& frame,
bool last_frame_in_packet,
InFecGroup is_in_fec_group,
QuicSequenceNumberLength sequence_number_length);
static bool AppendPacketSequenceNumber(
QuicSequenceNumberLength sequence_number_length,
QuicPacketSequenceNumber packet_sequence_number,
QuicDataWriter* writer);
static uint8 GetSequenceNumberFlags(
QuicSequenceNumberLength sequence_number_length);
static AckFrameInfo GetAckFrameInfo(const QuicAckFrame& frame);
// The Append* methods attempt to write the provided header or frame using the
// |writer|, and return true if successful.
bool AppendPacketHeader(const QuicPacketHeader& header,
QuicDataWriter* writer);
bool AppendTypeByte(const QuicFrame& frame,
bool last_frame_in_packet,
QuicDataWriter* writer);
bool AppendStreamFrame(const QuicStreamFrame& frame,
bool last_frame_in_packet,
QuicDataWriter* builder);
bool AppendAckFrameAndTypeByte(const QuicPacketHeader& header,
const QuicAckFrame& frame,
QuicDataWriter* builder);
bool AppendCongestionFeedbackFrame(const QuicCongestionFeedbackFrame& frame,
QuicDataWriter* builder);
bool AppendStopWaitingFrame(const QuicPacketHeader& header,
const QuicStopWaitingFrame& frame,
QuicDataWriter* builder);
bool AppendRstStreamFrame(const QuicRstStreamFrame& frame,
QuicDataWriter* builder);
bool AppendConnectionCloseFrame(const QuicConnectionCloseFrame& frame,
QuicDataWriter* builder);
bool AppendGoAwayFrame(const QuicGoAwayFrame& frame, QuicDataWriter* writer);
bool AppendWindowUpdateFrame(const QuicWindowUpdateFrame& frame,
QuicDataWriter* writer);
bool AppendBlockedFrame(const QuicBlockedFrame& frame,
QuicDataWriter* writer);
bool RaiseError(QuicErrorCode error);
void set_error(QuicErrorCode error) {
error_ = error;
}
void set_detailed_error(const char* error) {
detailed_error_ = error;
}
std::string detailed_error_;
scoped_ptr<QuicDataReader> reader_;
QuicFramerVisitorInterface* visitor_;
QuicFecBuilderInterface* fec_builder_;
QuicReceivedEntropyHashCalculatorInterface* entropy_calculator_;
QuicErrorCode error_;
// Updated by ProcessPacketHeader when it succeeds.
QuicPacketSequenceNumber last_sequence_number_;
// Updated by WritePacketHeader.
QuicConnectionId last_serialized_connection_id_;
// Buffer containing decrypted payload data during parsing.
scoped_ptr<QuicData> decrypted_;
// Version of the protocol being used.
QuicVersion quic_version_;
// This vector contains QUIC versions which we currently support.
// This should be ordered such that the highest supported version is the first
// element, with subsequent elements in descending order (versions can be
// skipped as necessary).
QuicVersionVector supported_versions_;
// Primary decrypter used to decrypt packets during parsing.
scoped_ptr<QuicDecrypter> decrypter_;
// Alternative decrypter that can also be used to decrypt packets.
scoped_ptr<QuicDecrypter> alternative_decrypter_;
// alternative_decrypter_latch_is true if, when |alternative_decrypter_|
// successfully decrypts a packet, we should install it as the only
// decrypter.
bool alternative_decrypter_latch_;
// Encrypters used to encrypt packets via EncryptPacket().
scoped_ptr<QuicEncrypter> encrypter_[NUM_ENCRYPTION_LEVELS];
// Tracks if the framer is being used by the entity that received the
// connection or the entity that initiated it.
bool is_server_;
// If false, skip validation that the public flags are set to legal values.
bool validate_flags_;
// The time this frames was created. Time written to the wire will be
// written as a delta from this value.
QuicTime creation_time_;
DISALLOW_COPY_AND_ASSIGN(QuicFramer);
};
} // namespace net
#endif // NET_QUIC_QUIC_FRAMER_H_