884 lines
27 KiB
Go
884 lines
27 KiB
Go
package quic
|
|
|
|
import (
|
|
"bytes"
|
|
"errors"
|
|
"fmt"
|
|
"net"
|
|
"time"
|
|
|
|
"github.com/lucas-clemente/quic-go/internal/ackhandler"
|
|
"github.com/lucas-clemente/quic-go/internal/handshake"
|
|
"github.com/lucas-clemente/quic-go/internal/protocol"
|
|
"github.com/lucas-clemente/quic-go/internal/qerr"
|
|
"github.com/lucas-clemente/quic-go/internal/utils"
|
|
"github.com/lucas-clemente/quic-go/internal/wire"
|
|
)
|
|
|
|
type packer interface {
|
|
PackCoalescedPacket() (*coalescedPacket, error)
|
|
PackPacket() (*packedPacket, error)
|
|
MaybePackProbePacket(protocol.EncryptionLevel) (*packedPacket, error)
|
|
MaybePackAckPacket(handshakeConfirmed bool) (*packedPacket, error)
|
|
PackConnectionClose(*qerr.QuicError) (*coalescedPacket, error)
|
|
|
|
SetMaxPacketSize(protocol.ByteCount)
|
|
PackMTUProbePacket(ping ackhandler.Frame, size protocol.ByteCount) (*packedPacket, error)
|
|
|
|
HandleTransportParameters(*wire.TransportParameters)
|
|
SetToken([]byte)
|
|
}
|
|
|
|
type sealer interface {
|
|
handshake.LongHeaderSealer
|
|
}
|
|
|
|
type payload struct {
|
|
frames []ackhandler.Frame
|
|
ack *wire.AckFrame
|
|
length protocol.ByteCount
|
|
}
|
|
|
|
type packedPacket struct {
|
|
buffer *packetBuffer
|
|
*packetContents
|
|
}
|
|
|
|
type packetContents struct {
|
|
header *wire.ExtendedHeader
|
|
ack *wire.AckFrame
|
|
frames []ackhandler.Frame
|
|
|
|
length protocol.ByteCount
|
|
|
|
isMTUProbePacket bool
|
|
}
|
|
|
|
type coalescedPacket struct {
|
|
buffer *packetBuffer
|
|
packets []*packetContents
|
|
}
|
|
|
|
func (p *packetContents) EncryptionLevel() protocol.EncryptionLevel {
|
|
if !p.header.IsLongHeader {
|
|
return protocol.Encryption1RTT
|
|
}
|
|
//nolint:exhaustive // Will never be called for Retry packets (and they don't have encrypted data).
|
|
switch p.header.Type {
|
|
case protocol.PacketTypeInitial:
|
|
return protocol.EncryptionInitial
|
|
case protocol.PacketTypeHandshake:
|
|
return protocol.EncryptionHandshake
|
|
case protocol.PacketType0RTT:
|
|
return protocol.Encryption0RTT
|
|
default:
|
|
panic("can't determine encryption level")
|
|
}
|
|
}
|
|
|
|
func (p *packetContents) IsAckEliciting() bool {
|
|
return ackhandler.HasAckElicitingFrames(p.frames)
|
|
}
|
|
|
|
func (p *packetContents) ToAckHandlerPacket(now time.Time, q *retransmissionQueue) *ackhandler.Packet {
|
|
largestAcked := protocol.InvalidPacketNumber
|
|
if p.ack != nil {
|
|
largestAcked = p.ack.LargestAcked()
|
|
}
|
|
encLevel := p.EncryptionLevel()
|
|
for i := range p.frames {
|
|
if p.frames[i].OnLost != nil {
|
|
continue
|
|
}
|
|
switch encLevel {
|
|
case protocol.EncryptionInitial:
|
|
p.frames[i].OnLost = q.AddInitial
|
|
case protocol.EncryptionHandshake:
|
|
p.frames[i].OnLost = q.AddHandshake
|
|
case protocol.Encryption0RTT, protocol.Encryption1RTT:
|
|
p.frames[i].OnLost = q.AddAppData
|
|
}
|
|
}
|
|
return &ackhandler.Packet{
|
|
PacketNumber: p.header.PacketNumber,
|
|
LargestAcked: largestAcked,
|
|
Frames: p.frames,
|
|
Length: p.length,
|
|
EncryptionLevel: encLevel,
|
|
SendTime: now,
|
|
IsPathMTUProbePacket: p.isMTUProbePacket,
|
|
}
|
|
}
|
|
|
|
func getMaxPacketSize(addr net.Addr) protocol.ByteCount {
|
|
maxSize := protocol.ByteCount(protocol.MinInitialPacketSize)
|
|
// If this is not a UDP address, we don't know anything about the MTU.
|
|
// Use the minimum size of an Initial packet as the max packet size.
|
|
if udpAddr, ok := addr.(*net.UDPAddr); ok {
|
|
if utils.IsIPv4(udpAddr.IP) {
|
|
maxSize = protocol.InitialPacketSizeIPv4
|
|
} else {
|
|
maxSize = protocol.InitialPacketSizeIPv6
|
|
}
|
|
}
|
|
return maxSize
|
|
}
|
|
|
|
type packetNumberManager interface {
|
|
PeekPacketNumber(protocol.EncryptionLevel) (protocol.PacketNumber, protocol.PacketNumberLen)
|
|
PopPacketNumber(protocol.EncryptionLevel) protocol.PacketNumber
|
|
}
|
|
|
|
type sealingManager interface {
|
|
GetInitialSealer() (handshake.LongHeaderSealer, error)
|
|
GetHandshakeSealer() (handshake.LongHeaderSealer, error)
|
|
Get0RTTSealer() (handshake.LongHeaderSealer, error)
|
|
Get1RTTSealer() (handshake.ShortHeaderSealer, error)
|
|
}
|
|
|
|
type frameSource interface {
|
|
HasData() bool
|
|
AppendStreamFrames([]ackhandler.Frame, protocol.ByteCount) ([]ackhandler.Frame, protocol.ByteCount)
|
|
AppendControlFrames([]ackhandler.Frame, protocol.ByteCount) ([]ackhandler.Frame, protocol.ByteCount)
|
|
}
|
|
|
|
type ackFrameSource interface {
|
|
GetAckFrame(encLevel protocol.EncryptionLevel, onlyIfQueued bool) *wire.AckFrame
|
|
}
|
|
|
|
type packetPacker struct {
|
|
srcConnID protocol.ConnectionID
|
|
getDestConnID func() protocol.ConnectionID
|
|
|
|
perspective protocol.Perspective
|
|
version protocol.VersionNumber
|
|
cryptoSetup sealingManager
|
|
|
|
initialStream cryptoStream
|
|
handshakeStream cryptoStream
|
|
|
|
token []byte
|
|
|
|
pnManager packetNumberManager
|
|
framer frameSource
|
|
acks ackFrameSource
|
|
datagramQueue *datagramQueue
|
|
retransmissionQueue *retransmissionQueue
|
|
|
|
maxPacketSize protocol.ByteCount
|
|
numNonAckElicitingAcks int
|
|
}
|
|
|
|
var _ packer = &packetPacker{}
|
|
|
|
func newPacketPacker(
|
|
srcConnID protocol.ConnectionID,
|
|
getDestConnID func() protocol.ConnectionID,
|
|
initialStream cryptoStream,
|
|
handshakeStream cryptoStream,
|
|
packetNumberManager packetNumberManager,
|
|
retransmissionQueue *retransmissionQueue,
|
|
remoteAddr net.Addr, // only used for determining the max packet size
|
|
cryptoSetup sealingManager,
|
|
framer frameSource,
|
|
acks ackFrameSource,
|
|
datagramQueue *datagramQueue,
|
|
perspective protocol.Perspective,
|
|
version protocol.VersionNumber,
|
|
) *packetPacker {
|
|
return &packetPacker{
|
|
cryptoSetup: cryptoSetup,
|
|
getDestConnID: getDestConnID,
|
|
srcConnID: srcConnID,
|
|
initialStream: initialStream,
|
|
handshakeStream: handshakeStream,
|
|
retransmissionQueue: retransmissionQueue,
|
|
datagramQueue: datagramQueue,
|
|
perspective: perspective,
|
|
version: version,
|
|
framer: framer,
|
|
acks: acks,
|
|
pnManager: packetNumberManager,
|
|
maxPacketSize: getMaxPacketSize(remoteAddr),
|
|
}
|
|
}
|
|
|
|
// PackConnectionClose packs a packet that ONLY contains a ConnectionCloseFrame
|
|
func (p *packetPacker) PackConnectionClose(quicErr *qerr.QuicError) (*coalescedPacket, error) {
|
|
var reason string
|
|
// don't send details of crypto errors
|
|
if !quicErr.IsCryptoError() {
|
|
reason = quicErr.ErrorMessage
|
|
}
|
|
|
|
var sealers [4]sealer
|
|
var hdrs [4]*wire.ExtendedHeader
|
|
var payloads [4]*payload
|
|
var size protocol.ByteCount
|
|
var numPackets uint8
|
|
encLevels := [4]protocol.EncryptionLevel{protocol.EncryptionInitial, protocol.EncryptionHandshake, protocol.Encryption0RTT, protocol.Encryption1RTT}
|
|
for i, encLevel := range encLevels {
|
|
if p.perspective == protocol.PerspectiveServer && encLevel == protocol.Encryption0RTT {
|
|
continue
|
|
}
|
|
quicErrToSend := quicErr
|
|
reasonPhrase := reason
|
|
if encLevel == protocol.EncryptionInitial || encLevel == protocol.EncryptionHandshake {
|
|
// don't send application errors in Initial or Handshake packets
|
|
if quicErr.IsApplicationError() {
|
|
quicErrToSend = qerr.NewError(qerr.ApplicationError, "")
|
|
reasonPhrase = ""
|
|
}
|
|
}
|
|
ccf := &wire.ConnectionCloseFrame{
|
|
IsApplicationError: quicErrToSend.IsApplicationError(),
|
|
ErrorCode: quicErrToSend.ErrorCode,
|
|
FrameType: quicErrToSend.FrameType,
|
|
ReasonPhrase: reasonPhrase,
|
|
}
|
|
payload := &payload{
|
|
frames: []ackhandler.Frame{{Frame: ccf}},
|
|
length: ccf.Length(p.version),
|
|
}
|
|
|
|
var sealer sealer
|
|
var err error
|
|
var keyPhase protocol.KeyPhaseBit // only set for 1-RTT
|
|
switch encLevel {
|
|
case protocol.EncryptionInitial:
|
|
sealer, err = p.cryptoSetup.GetInitialSealer()
|
|
case protocol.EncryptionHandshake:
|
|
sealer, err = p.cryptoSetup.GetHandshakeSealer()
|
|
case protocol.Encryption0RTT:
|
|
sealer, err = p.cryptoSetup.Get0RTTSealer()
|
|
case protocol.Encryption1RTT:
|
|
var s handshake.ShortHeaderSealer
|
|
s, err = p.cryptoSetup.Get1RTTSealer()
|
|
if err == nil {
|
|
keyPhase = s.KeyPhase()
|
|
}
|
|
sealer = s
|
|
}
|
|
if err == handshake.ErrKeysNotYetAvailable || err == handshake.ErrKeysDropped {
|
|
continue
|
|
}
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
sealers[i] = sealer
|
|
var hdr *wire.ExtendedHeader
|
|
if encLevel == protocol.Encryption1RTT {
|
|
hdr = p.getShortHeader(keyPhase)
|
|
} else {
|
|
hdr = p.getLongHeader(encLevel)
|
|
}
|
|
hdrs[i] = hdr
|
|
payloads[i] = payload
|
|
size += p.packetLength(hdr, payload) + protocol.ByteCount(sealer.Overhead())
|
|
numPackets++
|
|
}
|
|
contents := make([]*packetContents, 0, numPackets)
|
|
buffer := getPacketBuffer()
|
|
for i, encLevel := range encLevels {
|
|
if sealers[i] == nil {
|
|
continue
|
|
}
|
|
var paddingLen protocol.ByteCount
|
|
if encLevel == protocol.EncryptionInitial {
|
|
paddingLen = p.initialPaddingLen(payloads[i].frames, size)
|
|
}
|
|
c, err := p.appendPacket(buffer, hdrs[i], payloads[i], paddingLen, encLevel, sealers[i], false)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
contents = append(contents, c)
|
|
}
|
|
return &coalescedPacket{buffer: buffer, packets: contents}, nil
|
|
}
|
|
|
|
// packetLength calculates the length of the serialized packet.
|
|
// It takes into account that packets that have a tiny payload need to be padded,
|
|
// such that len(payload) + packet number len >= 4 + AEAD overhead
|
|
func (p *packetPacker) packetLength(hdr *wire.ExtendedHeader, payload *payload) protocol.ByteCount {
|
|
var paddingLen protocol.ByteCount
|
|
pnLen := protocol.ByteCount(hdr.PacketNumberLen)
|
|
if payload.length < 4-pnLen {
|
|
paddingLen = 4 - pnLen - payload.length
|
|
}
|
|
return hdr.GetLength(p.version) + payload.length + paddingLen
|
|
}
|
|
|
|
func (p *packetPacker) MaybePackAckPacket(handshakeConfirmed bool) (*packedPacket, error) {
|
|
var encLevel protocol.EncryptionLevel
|
|
var ack *wire.AckFrame
|
|
if !handshakeConfirmed {
|
|
ack = p.acks.GetAckFrame(protocol.EncryptionInitial, true)
|
|
if ack != nil {
|
|
encLevel = protocol.EncryptionInitial
|
|
} else {
|
|
ack = p.acks.GetAckFrame(protocol.EncryptionHandshake, true)
|
|
if ack != nil {
|
|
encLevel = protocol.EncryptionHandshake
|
|
}
|
|
}
|
|
}
|
|
if ack == nil {
|
|
ack = p.acks.GetAckFrame(protocol.Encryption1RTT, true)
|
|
if ack == nil {
|
|
return nil, nil
|
|
}
|
|
encLevel = protocol.Encryption1RTT
|
|
}
|
|
payload := &payload{
|
|
ack: ack,
|
|
length: ack.Length(p.version),
|
|
}
|
|
|
|
sealer, hdr, err := p.getSealerAndHeader(encLevel)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return p.writeSinglePacket(hdr, payload, encLevel, sealer)
|
|
}
|
|
|
|
// size is the expected size of the packet, if no padding was applied.
|
|
func (p *packetPacker) initialPaddingLen(frames []ackhandler.Frame, size protocol.ByteCount) protocol.ByteCount {
|
|
// For the server, only ack-eliciting Initial packets need to be padded.
|
|
if p.perspective == protocol.PerspectiveServer && !ackhandler.HasAckElicitingFrames(frames) {
|
|
return 0
|
|
}
|
|
if size >= p.maxPacketSize {
|
|
return 0
|
|
}
|
|
return p.maxPacketSize - size
|
|
}
|
|
|
|
// PackCoalescedPacket packs a new packet.
|
|
// It packs an Initial / Handshake if there is data to send in these packet number spaces.
|
|
// It should only be called before the handshake is confirmed.
|
|
func (p *packetPacker) PackCoalescedPacket() (*coalescedPacket, error) {
|
|
maxPacketSize := p.maxPacketSize
|
|
if p.perspective == protocol.PerspectiveClient {
|
|
maxPacketSize = protocol.MinInitialPacketSize
|
|
}
|
|
var initialHdr, handshakeHdr, appDataHdr *wire.ExtendedHeader
|
|
var initialPayload, handshakePayload, appDataPayload *payload
|
|
var numPackets int
|
|
// Try packing an Initial packet.
|
|
initialSealer, err := p.cryptoSetup.GetInitialSealer()
|
|
if err != nil && err != handshake.ErrKeysDropped {
|
|
return nil, err
|
|
}
|
|
var size protocol.ByteCount
|
|
if initialSealer != nil {
|
|
initialHdr, initialPayload = p.maybeGetCryptoPacket(maxPacketSize-protocol.ByteCount(initialSealer.Overhead()), size, protocol.EncryptionInitial)
|
|
if initialPayload != nil {
|
|
size += p.packetLength(initialHdr, initialPayload) + protocol.ByteCount(initialSealer.Overhead())
|
|
numPackets++
|
|
}
|
|
}
|
|
|
|
// Add a Handshake packet.
|
|
var handshakeSealer sealer
|
|
if size < maxPacketSize-protocol.MinCoalescedPacketSize {
|
|
var err error
|
|
handshakeSealer, err = p.cryptoSetup.GetHandshakeSealer()
|
|
if err != nil && err != handshake.ErrKeysDropped && err != handshake.ErrKeysNotYetAvailable {
|
|
return nil, err
|
|
}
|
|
if handshakeSealer != nil {
|
|
handshakeHdr, handshakePayload = p.maybeGetCryptoPacket(maxPacketSize-size-protocol.ByteCount(handshakeSealer.Overhead()), size, protocol.EncryptionHandshake)
|
|
if handshakePayload != nil {
|
|
s := p.packetLength(handshakeHdr, handshakePayload) + protocol.ByteCount(handshakeSealer.Overhead())
|
|
size += s
|
|
numPackets++
|
|
}
|
|
}
|
|
}
|
|
|
|
// Add a 0-RTT / 1-RTT packet.
|
|
var appDataSealer sealer
|
|
appDataEncLevel := protocol.Encryption1RTT
|
|
if size < maxPacketSize-protocol.MinCoalescedPacketSize {
|
|
var err error
|
|
appDataSealer, appDataHdr, appDataPayload = p.maybeGetAppDataPacket(maxPacketSize-size, size)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
if appDataHdr != nil {
|
|
if appDataHdr.IsLongHeader {
|
|
appDataEncLevel = protocol.Encryption0RTT
|
|
}
|
|
if appDataPayload != nil {
|
|
size += p.packetLength(appDataHdr, appDataPayload) + protocol.ByteCount(appDataSealer.Overhead())
|
|
numPackets++
|
|
}
|
|
}
|
|
}
|
|
|
|
if numPackets == 0 {
|
|
return nil, nil
|
|
}
|
|
|
|
buffer := getPacketBuffer()
|
|
packet := &coalescedPacket{
|
|
buffer: buffer,
|
|
packets: make([]*packetContents, 0, numPackets),
|
|
}
|
|
if initialPayload != nil {
|
|
padding := p.initialPaddingLen(initialPayload.frames, size)
|
|
cont, err := p.appendPacket(buffer, initialHdr, initialPayload, padding, protocol.EncryptionInitial, initialSealer, false)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
packet.packets = append(packet.packets, cont)
|
|
}
|
|
if handshakePayload != nil {
|
|
cont, err := p.appendPacket(buffer, handshakeHdr, handshakePayload, 0, protocol.EncryptionHandshake, handshakeSealer, false)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
packet.packets = append(packet.packets, cont)
|
|
}
|
|
if appDataPayload != nil {
|
|
cont, err := p.appendPacket(buffer, appDataHdr, appDataPayload, 0, appDataEncLevel, appDataSealer, false)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
packet.packets = append(packet.packets, cont)
|
|
}
|
|
return packet, nil
|
|
}
|
|
|
|
// PackPacket packs a packet in the application data packet number space.
|
|
// It should be called after the handshake is confirmed.
|
|
func (p *packetPacker) PackPacket() (*packedPacket, error) {
|
|
sealer, hdr, payload := p.maybeGetAppDataPacket(p.maxPacketSize, 0)
|
|
if payload == nil {
|
|
return nil, nil
|
|
}
|
|
buffer := getPacketBuffer()
|
|
encLevel := protocol.Encryption1RTT
|
|
if hdr.IsLongHeader {
|
|
encLevel = protocol.Encryption0RTT
|
|
}
|
|
cont, err := p.appendPacket(buffer, hdr, payload, 0, encLevel, sealer, false)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return &packedPacket{
|
|
buffer: buffer,
|
|
packetContents: cont,
|
|
}, nil
|
|
}
|
|
|
|
func (p *packetPacker) maybeGetCryptoPacket(maxPacketSize, currentSize protocol.ByteCount, encLevel protocol.EncryptionLevel) (*wire.ExtendedHeader, *payload) {
|
|
var s cryptoStream
|
|
var hasRetransmission bool
|
|
//nolint:exhaustive // Initial and Handshake are the only two encryption levels here.
|
|
switch encLevel {
|
|
case protocol.EncryptionInitial:
|
|
s = p.initialStream
|
|
hasRetransmission = p.retransmissionQueue.HasInitialData()
|
|
case protocol.EncryptionHandshake:
|
|
s = p.handshakeStream
|
|
hasRetransmission = p.retransmissionQueue.HasHandshakeData()
|
|
}
|
|
|
|
hasData := s.HasData()
|
|
var ack *wire.AckFrame
|
|
if encLevel == protocol.EncryptionInitial || currentSize == 0 {
|
|
ack = p.acks.GetAckFrame(encLevel, !hasRetransmission && !hasData)
|
|
}
|
|
if !hasData && !hasRetransmission && ack == nil {
|
|
// nothing to send
|
|
return nil, nil
|
|
}
|
|
|
|
var payload payload
|
|
if ack != nil {
|
|
payload.ack = ack
|
|
payload.length = ack.Length(p.version)
|
|
maxPacketSize -= payload.length
|
|
}
|
|
hdr := p.getLongHeader(encLevel)
|
|
maxPacketSize -= hdr.GetLength(p.version)
|
|
if hasRetransmission {
|
|
for {
|
|
var f wire.Frame
|
|
//nolint:exhaustive // 0-RTT packets can't contain any retransmission.s
|
|
switch encLevel {
|
|
case protocol.EncryptionInitial:
|
|
f = p.retransmissionQueue.GetInitialFrame(maxPacketSize)
|
|
case protocol.EncryptionHandshake:
|
|
f = p.retransmissionQueue.GetHandshakeFrame(maxPacketSize)
|
|
}
|
|
if f == nil {
|
|
break
|
|
}
|
|
payload.frames = append(payload.frames, ackhandler.Frame{Frame: f})
|
|
frameLen := f.Length(p.version)
|
|
payload.length += frameLen
|
|
maxPacketSize -= frameLen
|
|
}
|
|
} else if s.HasData() {
|
|
cf := s.PopCryptoFrame(maxPacketSize)
|
|
payload.frames = []ackhandler.Frame{{Frame: cf}}
|
|
payload.length += cf.Length(p.version)
|
|
}
|
|
return hdr, &payload
|
|
}
|
|
|
|
func (p *packetPacker) maybeGetAppDataPacket(maxPacketSize, currentSize protocol.ByteCount) (sealer, *wire.ExtendedHeader, *payload) {
|
|
var sealer sealer
|
|
var encLevel protocol.EncryptionLevel
|
|
var hdr *wire.ExtendedHeader
|
|
oneRTTSealer, err := p.cryptoSetup.Get1RTTSealer()
|
|
if err == nil {
|
|
encLevel = protocol.Encryption1RTT
|
|
sealer = oneRTTSealer
|
|
hdr = p.getShortHeader(oneRTTSealer.KeyPhase())
|
|
} else {
|
|
// 1-RTT sealer not yet available
|
|
if p.perspective != protocol.PerspectiveClient {
|
|
return nil, nil, nil
|
|
}
|
|
sealer, err = p.cryptoSetup.Get0RTTSealer()
|
|
if sealer == nil || err != nil {
|
|
return nil, nil, nil
|
|
}
|
|
encLevel = protocol.Encryption0RTT
|
|
hdr = p.getLongHeader(protocol.Encryption0RTT)
|
|
}
|
|
|
|
maxPayloadSize := maxPacketSize - hdr.GetLength(p.version) - protocol.ByteCount(sealer.Overhead())
|
|
payload := p.maybeGetAppDataPacketWithEncLevel(maxPayloadSize, encLevel == protocol.Encryption1RTT && currentSize == 0)
|
|
return sealer, hdr, payload
|
|
}
|
|
|
|
func (p *packetPacker) maybeGetAppDataPacketWithEncLevel(maxPayloadSize protocol.ByteCount, ackAllowed bool) *payload {
|
|
payload := p.composeNextPacket(maxPayloadSize, ackAllowed)
|
|
|
|
// check if we have anything to send
|
|
if len(payload.frames) == 0 {
|
|
if payload.ack == nil {
|
|
return nil
|
|
}
|
|
// the packet only contains an ACK
|
|
if p.numNonAckElicitingAcks >= protocol.MaxNonAckElicitingAcks {
|
|
ping := &wire.PingFrame{}
|
|
// don't retransmit the PING frame when it is lost
|
|
payload.frames = append(payload.frames, ackhandler.Frame{Frame: ping, OnLost: func(wire.Frame) {}})
|
|
payload.length += ping.Length(p.version)
|
|
p.numNonAckElicitingAcks = 0
|
|
} else {
|
|
p.numNonAckElicitingAcks++
|
|
}
|
|
} else {
|
|
p.numNonAckElicitingAcks = 0
|
|
}
|
|
return payload
|
|
}
|
|
|
|
func (p *packetPacker) composeNextPacket(maxFrameSize protocol.ByteCount, ackAllowed bool) *payload {
|
|
payload := &payload{frames: make([]ackhandler.Frame, 0, 1)}
|
|
|
|
var hasDatagram bool
|
|
if p.datagramQueue != nil {
|
|
if datagram := p.datagramQueue.Get(); datagram != nil {
|
|
payload.frames = append(payload.frames, ackhandler.Frame{
|
|
Frame: datagram,
|
|
// set it to a no-op. Then we won't set the default callback, which would retransmit the frame.
|
|
OnLost: func(wire.Frame) {},
|
|
})
|
|
payload.length += datagram.Length(p.version)
|
|
hasDatagram = true
|
|
}
|
|
}
|
|
|
|
var ack *wire.AckFrame
|
|
hasData := p.framer.HasData()
|
|
hasRetransmission := p.retransmissionQueue.HasAppData()
|
|
// TODO: make sure ACKs are sent when a lot of DATAGRAMs are queued
|
|
if !hasDatagram && ackAllowed {
|
|
ack = p.acks.GetAckFrame(protocol.Encryption1RTT, !hasRetransmission && !hasData)
|
|
if ack != nil {
|
|
payload.ack = ack
|
|
payload.length += ack.Length(p.version)
|
|
}
|
|
}
|
|
|
|
if ack == nil && !hasData && !hasRetransmission {
|
|
return payload
|
|
}
|
|
|
|
if hasRetransmission {
|
|
for {
|
|
remainingLen := maxFrameSize - payload.length
|
|
if remainingLen < protocol.MinStreamFrameSize {
|
|
break
|
|
}
|
|
f := p.retransmissionQueue.GetAppDataFrame(remainingLen)
|
|
if f == nil {
|
|
break
|
|
}
|
|
payload.frames = append(payload.frames, ackhandler.Frame{Frame: f})
|
|
payload.length += f.Length(p.version)
|
|
}
|
|
}
|
|
|
|
if hasData {
|
|
var lengthAdded protocol.ByteCount
|
|
payload.frames, lengthAdded = p.framer.AppendControlFrames(payload.frames, maxFrameSize-payload.length)
|
|
payload.length += lengthAdded
|
|
|
|
payload.frames, lengthAdded = p.framer.AppendStreamFrames(payload.frames, maxFrameSize-payload.length)
|
|
payload.length += lengthAdded
|
|
}
|
|
return payload
|
|
}
|
|
|
|
func (p *packetPacker) MaybePackProbePacket(encLevel protocol.EncryptionLevel) (*packedPacket, error) {
|
|
var hdr *wire.ExtendedHeader
|
|
var payload *payload
|
|
var sealer sealer
|
|
//nolint:exhaustive // Probe packets are never sent for 0-RTT.
|
|
switch encLevel {
|
|
case protocol.EncryptionInitial:
|
|
var err error
|
|
sealer, err = p.cryptoSetup.GetInitialSealer()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
hdr, payload = p.maybeGetCryptoPacket(p.maxPacketSize-protocol.ByteCount(sealer.Overhead()), 0, protocol.EncryptionInitial)
|
|
case protocol.EncryptionHandshake:
|
|
var err error
|
|
sealer, err = p.cryptoSetup.GetHandshakeSealer()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
hdr, payload = p.maybeGetCryptoPacket(p.maxPacketSize-protocol.ByteCount(sealer.Overhead()), 0, protocol.EncryptionHandshake)
|
|
case protocol.Encryption1RTT:
|
|
oneRTTSealer, err := p.cryptoSetup.Get1RTTSealer()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
sealer = oneRTTSealer
|
|
hdr = p.getShortHeader(oneRTTSealer.KeyPhase())
|
|
payload = p.maybeGetAppDataPacketWithEncLevel(p.maxPacketSize-protocol.ByteCount(sealer.Overhead())-hdr.GetLength(p.version), true)
|
|
default:
|
|
panic("unknown encryption level")
|
|
}
|
|
if payload == nil {
|
|
return nil, nil
|
|
}
|
|
size := p.packetLength(hdr, payload) + protocol.ByteCount(sealer.Overhead())
|
|
var padding protocol.ByteCount
|
|
if encLevel == protocol.EncryptionInitial {
|
|
padding = p.initialPaddingLen(payload.frames, size)
|
|
}
|
|
buffer := getPacketBuffer()
|
|
cont, err := p.appendPacket(buffer, hdr, payload, padding, encLevel, sealer, false)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return &packedPacket{
|
|
buffer: buffer,
|
|
packetContents: cont,
|
|
}, nil
|
|
}
|
|
|
|
func (p *packetPacker) PackMTUProbePacket(ping ackhandler.Frame, size protocol.ByteCount) (*packedPacket, error) {
|
|
payload := &payload{
|
|
frames: []ackhandler.Frame{ping},
|
|
length: ping.Length(p.version),
|
|
}
|
|
buffer := getPacketBuffer()
|
|
sealer, err := p.cryptoSetup.Get1RTTSealer()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
hdr := p.getShortHeader(sealer.KeyPhase())
|
|
padding := size - p.packetLength(hdr, payload) - protocol.ByteCount(sealer.Overhead())
|
|
contents, err := p.appendPacket(buffer, hdr, payload, padding, protocol.Encryption1RTT, sealer, true)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
contents.isMTUProbePacket = true
|
|
return &packedPacket{
|
|
buffer: buffer,
|
|
packetContents: contents,
|
|
}, nil
|
|
}
|
|
|
|
func (p *packetPacker) getSealerAndHeader(encLevel protocol.EncryptionLevel) (sealer, *wire.ExtendedHeader, error) {
|
|
switch encLevel {
|
|
case protocol.EncryptionInitial:
|
|
sealer, err := p.cryptoSetup.GetInitialSealer()
|
|
if err != nil {
|
|
return nil, nil, err
|
|
}
|
|
hdr := p.getLongHeader(protocol.EncryptionInitial)
|
|
return sealer, hdr, nil
|
|
case protocol.Encryption0RTT:
|
|
sealer, err := p.cryptoSetup.Get0RTTSealer()
|
|
if err != nil {
|
|
return nil, nil, err
|
|
}
|
|
hdr := p.getLongHeader(protocol.Encryption0RTT)
|
|
return sealer, hdr, nil
|
|
case protocol.EncryptionHandshake:
|
|
sealer, err := p.cryptoSetup.GetHandshakeSealer()
|
|
if err != nil {
|
|
return nil, nil, err
|
|
}
|
|
hdr := p.getLongHeader(protocol.EncryptionHandshake)
|
|
return sealer, hdr, nil
|
|
case protocol.Encryption1RTT:
|
|
sealer, err := p.cryptoSetup.Get1RTTSealer()
|
|
if err != nil {
|
|
return nil, nil, err
|
|
}
|
|
hdr := p.getShortHeader(sealer.KeyPhase())
|
|
return sealer, hdr, nil
|
|
default:
|
|
return nil, nil, fmt.Errorf("unexpected encryption level: %s", encLevel)
|
|
}
|
|
}
|
|
|
|
func (p *packetPacker) getShortHeader(kp protocol.KeyPhaseBit) *wire.ExtendedHeader {
|
|
pn, pnLen := p.pnManager.PeekPacketNumber(protocol.Encryption1RTT)
|
|
hdr := &wire.ExtendedHeader{}
|
|
hdr.PacketNumber = pn
|
|
hdr.PacketNumberLen = pnLen
|
|
hdr.DestConnectionID = p.getDestConnID()
|
|
hdr.KeyPhase = kp
|
|
return hdr
|
|
}
|
|
|
|
func (p *packetPacker) getLongHeader(encLevel protocol.EncryptionLevel) *wire.ExtendedHeader {
|
|
pn, pnLen := p.pnManager.PeekPacketNumber(encLevel)
|
|
hdr := &wire.ExtendedHeader{
|
|
PacketNumber: pn,
|
|
PacketNumberLen: pnLen,
|
|
}
|
|
hdr.IsLongHeader = true
|
|
hdr.Version = p.version
|
|
hdr.SrcConnectionID = p.srcConnID
|
|
hdr.DestConnectionID = p.getDestConnID()
|
|
|
|
//nolint:exhaustive // 1-RTT packets are not long header packets.
|
|
switch encLevel {
|
|
case protocol.EncryptionInitial:
|
|
hdr.Type = protocol.PacketTypeInitial
|
|
hdr.Token = p.token
|
|
case protocol.EncryptionHandshake:
|
|
hdr.Type = protocol.PacketTypeHandshake
|
|
case protocol.Encryption0RTT:
|
|
hdr.Type = protocol.PacketType0RTT
|
|
}
|
|
return hdr
|
|
}
|
|
|
|
// writeSinglePacket packs a single packet.
|
|
func (p *packetPacker) writeSinglePacket(
|
|
hdr *wire.ExtendedHeader,
|
|
payload *payload,
|
|
encLevel protocol.EncryptionLevel,
|
|
sealer sealer,
|
|
) (*packedPacket, error) {
|
|
buffer := getPacketBuffer()
|
|
var paddingLen protocol.ByteCount
|
|
if encLevel == protocol.EncryptionInitial {
|
|
paddingLen = p.initialPaddingLen(payload.frames, hdr.GetLength(p.version)+payload.length+protocol.ByteCount(sealer.Overhead()))
|
|
}
|
|
contents, err := p.appendPacket(buffer, hdr, payload, paddingLen, encLevel, sealer, false)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return &packedPacket{
|
|
buffer: buffer,
|
|
packetContents: contents,
|
|
}, nil
|
|
}
|
|
|
|
func (p *packetPacker) appendPacket(buffer *packetBuffer, header *wire.ExtendedHeader, payload *payload, padding protocol.ByteCount, encLevel protocol.EncryptionLevel, sealer sealer, isMTUProbePacket bool) (*packetContents, error) {
|
|
var paddingLen protocol.ByteCount
|
|
pnLen := protocol.ByteCount(header.PacketNumberLen)
|
|
if payload.length < 4-pnLen {
|
|
paddingLen = 4 - pnLen - payload.length
|
|
}
|
|
paddingLen += padding
|
|
if header.IsLongHeader {
|
|
header.Length = pnLen + protocol.ByteCount(sealer.Overhead()) + payload.length + paddingLen
|
|
}
|
|
|
|
hdrOffset := buffer.Len()
|
|
buf := bytes.NewBuffer(buffer.Data)
|
|
if err := header.Write(buf, p.version); err != nil {
|
|
return nil, err
|
|
}
|
|
payloadOffset := buf.Len()
|
|
|
|
if payload.ack != nil {
|
|
if err := payload.ack.Write(buf, p.version); err != nil {
|
|
return nil, err
|
|
}
|
|
}
|
|
if paddingLen > 0 {
|
|
buf.Write(make([]byte, paddingLen))
|
|
}
|
|
for _, frame := range payload.frames {
|
|
if err := frame.Write(buf, p.version); err != nil {
|
|
return nil, err
|
|
}
|
|
}
|
|
|
|
if payloadSize := protocol.ByteCount(buf.Len()-payloadOffset) - paddingLen; payloadSize != payload.length {
|
|
return nil, fmt.Errorf("PacketPacker BUG: payload size inconsistent (expected %d, got %d bytes)", payload.length, payloadSize)
|
|
}
|
|
if !isMTUProbePacket {
|
|
if size := protocol.ByteCount(buf.Len() + sealer.Overhead()); size > p.maxPacketSize {
|
|
return nil, fmt.Errorf("PacketPacker BUG: packet too large (%d bytes, allowed %d bytes)", size, p.maxPacketSize)
|
|
}
|
|
}
|
|
|
|
raw := buffer.Data
|
|
// encrypt the packet
|
|
raw = raw[:buf.Len()]
|
|
_ = sealer.Seal(raw[payloadOffset:payloadOffset], raw[payloadOffset:], header.PacketNumber, raw[hdrOffset:payloadOffset])
|
|
raw = raw[0 : buf.Len()+sealer.Overhead()]
|
|
// apply header protection
|
|
pnOffset := payloadOffset - int(header.PacketNumberLen)
|
|
sealer.EncryptHeader(raw[pnOffset+4:pnOffset+4+16], &raw[hdrOffset], raw[pnOffset:payloadOffset])
|
|
buffer.Data = raw
|
|
|
|
num := p.pnManager.PopPacketNumber(encLevel)
|
|
if num != header.PacketNumber {
|
|
return nil, errors.New("packetPacker BUG: Peeked and Popped packet numbers do not match")
|
|
}
|
|
return &packetContents{
|
|
header: header,
|
|
ack: payload.ack,
|
|
frames: payload.frames,
|
|
length: buffer.Len() - hdrOffset,
|
|
}, nil
|
|
}
|
|
|
|
func (p *packetPacker) SetToken(token []byte) {
|
|
p.token = token
|
|
}
|
|
|
|
// When a higher MTU is discovered, use it.
|
|
func (p *packetPacker) SetMaxPacketSize(s protocol.ByteCount) {
|
|
p.maxPacketSize = s
|
|
}
|
|
|
|
// If the peer sets a max_packet_size that's smaller than the size we're currently using,
|
|
// we need to reduce the size of packets we send.
|
|
func (p *packetPacker) HandleTransportParameters(params *wire.TransportParameters) {
|
|
if params.MaxUDPPayloadSize != 0 {
|
|
p.maxPacketSize = utils.MinByteCount(p.maxPacketSize, params.MaxUDPPayloadSize)
|
|
}
|
|
}
|