cloudflared-mirror/vendor/github.com/lucas-clemente/quic-go/multiplexer.go

108 lines
2.8 KiB
Go

package quic
import (
"bytes"
"fmt"
"net"
"sync"
"github.com/lucas-clemente/quic-go/internal/utils"
"github.com/lucas-clemente/quic-go/logging"
)
var (
connMuxerOnce sync.Once
connMuxer multiplexer
)
type indexableConn interface {
LocalAddr() net.Addr
}
type multiplexer interface {
AddConn(c net.PacketConn, connIDLen int, statelessResetKey []byte, tracer logging.Tracer) (packetHandlerManager, error)
RemoveConn(indexableConn) error
}
type connManager struct {
connIDLen int
statelessResetKey []byte
tracer logging.Tracer
manager packetHandlerManager
}
// The connMultiplexer listens on multiple net.PacketConns and dispatches
// incoming packets to the connection handler.
type connMultiplexer struct {
mutex sync.Mutex
conns map[string] /* LocalAddr().String() */ connManager
newPacketHandlerManager func(net.PacketConn, int, []byte, logging.Tracer, utils.Logger) (packetHandlerManager, error) // so it can be replaced in the tests
logger utils.Logger
}
var _ multiplexer = &connMultiplexer{}
func getMultiplexer() multiplexer {
connMuxerOnce.Do(func() {
connMuxer = &connMultiplexer{
conns: make(map[string]connManager),
logger: utils.DefaultLogger.WithPrefix("muxer"),
newPacketHandlerManager: newPacketHandlerMap,
}
})
return connMuxer
}
func (m *connMultiplexer) AddConn(
c net.PacketConn,
connIDLen int,
statelessResetKey []byte,
tracer logging.Tracer,
) (packetHandlerManager, error) {
m.mutex.Lock()
defer m.mutex.Unlock()
addr := c.LocalAddr()
connIndex := addr.Network() + " " + addr.String()
p, ok := m.conns[connIndex]
if !ok {
manager, err := m.newPacketHandlerManager(c, connIDLen, statelessResetKey, tracer, m.logger)
if err != nil {
return nil, err
}
p = connManager{
connIDLen: connIDLen,
statelessResetKey: statelessResetKey,
manager: manager,
tracer: tracer,
}
m.conns[connIndex] = p
} else {
if p.connIDLen != connIDLen {
return nil, fmt.Errorf("cannot use %d byte connection IDs on a connection that is already using %d byte connction IDs", connIDLen, p.connIDLen)
}
if statelessResetKey != nil && !bytes.Equal(p.statelessResetKey, statelessResetKey) {
return nil, fmt.Errorf("cannot use different stateless reset keys on the same packet conn")
}
if tracer != p.tracer {
return nil, fmt.Errorf("cannot use different tracers on the same packet conn")
}
}
return p.manager, nil
}
func (m *connMultiplexer) RemoveConn(c indexableConn) error {
m.mutex.Lock()
defer m.mutex.Unlock()
connIndex := c.LocalAddr().Network() + " " + c.LocalAddr().String()
if _, ok := m.conns[connIndex]; !ok {
return fmt.Errorf("cannote remove connection, connection is unknown")
}
delete(m.conns, connIndex)
return nil
}