dnscrypt-proxy/vendor/github.com/quic-go/quic-go/internal/ackhandler/received_packet_handler.go

126 lines
4.0 KiB
Go

package ackhandler
import (
"fmt"
"time"
"github.com/quic-go/quic-go/internal/protocol"
"github.com/quic-go/quic-go/internal/utils"
"github.com/quic-go/quic-go/internal/wire"
)
type receivedPacketHandler struct {
sentPackets sentPacketTracker
initialPackets *receivedPacketTracker
handshakePackets *receivedPacketTracker
appDataPackets appDataReceivedPacketTracker
lowest1RTTPacket protocol.PacketNumber
}
var _ ReceivedPacketHandler = &receivedPacketHandler{}
func newReceivedPacketHandler(sentPackets sentPacketTracker, logger utils.Logger) ReceivedPacketHandler {
return &receivedPacketHandler{
sentPackets: sentPackets,
initialPackets: newReceivedPacketTracker(),
handshakePackets: newReceivedPacketTracker(),
appDataPackets: *newAppDataReceivedPacketTracker(logger),
lowest1RTTPacket: protocol.InvalidPacketNumber,
}
}
func (h *receivedPacketHandler) ReceivedPacket(
pn protocol.PacketNumber,
ecn protocol.ECN,
encLevel protocol.EncryptionLevel,
rcvTime time.Time,
ackEliciting bool,
) error {
h.sentPackets.ReceivedPacket(encLevel)
switch encLevel {
case protocol.EncryptionInitial:
return h.initialPackets.ReceivedPacket(pn, ecn, rcvTime, ackEliciting)
case protocol.EncryptionHandshake:
// The Handshake packet number space might already have been dropped as a result
// of processing the CRYPTO frame that was contained in this packet.
if h.handshakePackets == nil {
return nil
}
return h.handshakePackets.ReceivedPacket(pn, ecn, rcvTime, ackEliciting)
case protocol.Encryption0RTT:
if h.lowest1RTTPacket != protocol.InvalidPacketNumber && pn > h.lowest1RTTPacket {
return fmt.Errorf("received packet number %d on a 0-RTT packet after receiving %d on a 1-RTT packet", pn, h.lowest1RTTPacket)
}
return h.appDataPackets.ReceivedPacket(pn, ecn, rcvTime, ackEliciting)
case protocol.Encryption1RTT:
if h.lowest1RTTPacket == protocol.InvalidPacketNumber || pn < h.lowest1RTTPacket {
h.lowest1RTTPacket = pn
}
if err := h.appDataPackets.ReceivedPacket(pn, ecn, rcvTime, ackEliciting); err != nil {
return err
}
h.appDataPackets.IgnoreBelow(h.sentPackets.GetLowestPacketNotConfirmedAcked())
return nil
default:
panic(fmt.Sprintf("received packet with unknown encryption level: %s", encLevel))
}
}
func (h *receivedPacketHandler) DropPackets(encLevel protocol.EncryptionLevel) {
//nolint:exhaustive // 1-RTT packet number space is never dropped.
switch encLevel {
case protocol.EncryptionInitial:
h.initialPackets = nil
case protocol.EncryptionHandshake:
h.handshakePackets = nil
case protocol.Encryption0RTT:
// Nothing to do here.
// If we are rejecting 0-RTT, no 0-RTT packets will have been decrypted.
default:
panic(fmt.Sprintf("Cannot drop keys for encryption level %s", encLevel))
}
}
func (h *receivedPacketHandler) GetAlarmTimeout() time.Time {
return h.appDataPackets.GetAlarmTimeout()
}
func (h *receivedPacketHandler) GetAckFrame(encLevel protocol.EncryptionLevel, onlyIfQueued bool) *wire.AckFrame {
//nolint:exhaustive // 0-RTT packets can't contain ACK frames.
switch encLevel {
case protocol.EncryptionInitial:
if h.initialPackets != nil {
return h.initialPackets.GetAckFrame()
}
return nil
case protocol.EncryptionHandshake:
if h.handshakePackets != nil {
return h.handshakePackets.GetAckFrame()
}
return nil
case protocol.Encryption1RTT:
return h.appDataPackets.GetAckFrame(onlyIfQueued)
default:
// 0-RTT packets can't contain ACK frames
return nil
}
}
func (h *receivedPacketHandler) IsPotentiallyDuplicate(pn protocol.PacketNumber, encLevel protocol.EncryptionLevel) bool {
switch encLevel {
case protocol.EncryptionInitial:
if h.initialPackets != nil {
return h.initialPackets.IsPotentiallyDuplicate(pn)
}
case protocol.EncryptionHandshake:
if h.handshakePackets != nil {
return h.handshakePackets.IsPotentiallyDuplicate(pn)
}
case protocol.Encryption0RTT, protocol.Encryption1RTT:
return h.appDataPackets.IsPotentiallyDuplicate(pn)
}
panic("unexpected encryption level")
}