package quic import ( "context" "io" "sync" "time" "github.com/lucas-clemente/quic-go" "github.com/lucas-clemente/quic-go/logging" "github.com/lucas-clemente/quic-go/qlog" "github.com/xtls/xray-core/common" "github.com/xtls/xray-core/common/net" "github.com/xtls/xray-core/common/task" "github.com/xtls/xray-core/transport/internet" "github.com/xtls/xray-core/transport/internet/stat" "github.com/xtls/xray-core/transport/internet/tls" ) type connectionContext struct { rawConn *sysConn conn quic.Connection } var errConnectionClosed = newError("connection closed") func (c *connectionContext) openStream(destAddr net.Addr) (*interConn, error) { if !isActive(c.conn) { return nil, errConnectionClosed } stream, err := c.conn.OpenStream() if err != nil { return nil, err } conn := &interConn{ stream: stream, local: c.conn.LocalAddr(), remote: destAddr, } return conn, nil } type clientConnections struct { access sync.Mutex conns map[net.Destination][]*connectionContext cleanup *task.Periodic } func isActive(s quic.Connection) bool { select { case <-s.Context().Done(): return false default: return true } } func removeInactiveConnections(conns []*connectionContext) []*connectionContext { activeConnections := make([]*connectionContext, 0, len(conns)) for i, s := range conns { if isActive(s.conn) { activeConnections = append(activeConnections, s) continue } newError("closing quic connection at index: ", i).WriteToLog() if err := s.conn.CloseWithError(0, ""); err != nil { newError("failed to close connection").Base(err).WriteToLog() } if err := s.rawConn.Close(); err != nil { newError("failed to close raw connection").Base(err).WriteToLog() } } if len(activeConnections) < len(conns) { newError("active quic connection reduced from ", len(conns), " to ", len(activeConnections)).WriteToLog() return activeConnections } return conns } func (s *clientConnections) cleanConnections() error { s.access.Lock() defer s.access.Unlock() if len(s.conns) == 0 { return nil } newConnMap := make(map[net.Destination][]*connectionContext) for dest, conns := range s.conns { conns = removeInactiveConnections(conns) if len(conns) > 0 { newConnMap[dest] = conns } } s.conns = newConnMap return nil } func (s *clientConnections) openConnection(ctx context.Context, destAddr net.Addr, config *Config, tlsConfig *tls.Config, sockopt *internet.SocketConfig) (stat.Connection, error) { s.access.Lock() defer s.access.Unlock() if s.conns == nil { s.conns = make(map[net.Destination][]*connectionContext) } dest := net.DestinationFromAddr(destAddr) var conns []*connectionContext if s, found := s.conns[dest]; found { conns = s } if len(conns) > 0 { s := conns[len(conns)-1] if isActive(s.conn) { conn, err := s.openStream(destAddr) if err == nil { return conn, nil } newError("failed to openStream: ").Base(err).WriteToLog() } else { newError("current quic connection is not active!").WriteToLog() } } conns = removeInactiveConnections(conns) newError("dialing quic to ", dest).WriteToLog() rawConn, err := internet.DialSystem(ctx, dest, sockopt) if err != nil { return nil, newError("failed to dial to dest: ", err).AtWarning().Base(err) } quicConfig := &quic.Config{ ConnectionIDLength: 12, KeepAlive: false, Tracer: qlog.NewTracer(func(_ logging.Perspective, connID []byte) io.WriteCloser { return &QlogWriter{connID: connID} }), } udpConn, _ := rawConn.(*net.UDPConn) if udpConn == nil { udpConn = rawConn.(*internet.PacketConnWrapper).Conn.(*net.UDPConn) } sysConn, err := wrapSysConn(udpConn, config) if err != nil { rawConn.Close() return nil, err } conn, err := quic.DialContext(context.Background(), sysConn, destAddr, "", tlsConfig.GetTLSConfig(tls.WithDestination(dest)), quicConfig) if err != nil { sysConn.Close() return nil, err } context := &connectionContext{ conn: conn, rawConn: sysConn, } s.conns[dest] = append(conns, context) return context.openStream(destAddr) } var client clientConnections func init() { client.conns = make(map[net.Destination][]*connectionContext) client.cleanup = &task.Periodic{ Interval: time.Minute, Execute: client.cleanConnections, } common.Must(client.cleanup.Start()) } func Dial(ctx context.Context, dest net.Destination, streamSettings *internet.MemoryStreamConfig) (stat.Connection, error) { tlsConfig := tls.ConfigFromStreamSettings(streamSettings) if tlsConfig == nil { tlsConfig = &tls.Config{ ServerName: internalDomain, AllowInsecure: true, } } var destAddr *net.UDPAddr if dest.Address.Family().IsIP() { destAddr = &net.UDPAddr{ IP: dest.Address.IP(), Port: int(dest.Port), } } else { addr, err := net.ResolveUDPAddr("udp", dest.NetAddr()) if err != nil { return nil, err } destAddr = addr } config := streamSettings.ProtocolSettings.(*Config) return client.openConnection(ctx, destAddr, config, tlsConfig, streamSettings.SocketSettings) } func init() { common.Must(internet.RegisterTransportDialer(protocolName, Dial)) }