package quic import ( "context" "sync" "time" "github.com/lucas-clemente/quic-go" "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/tls" ) type sessionContext struct { rawConn *sysConn session quic.Session } var errSessionClosed = newError("session closed") func (c *sessionContext) openStream(destAddr net.Addr) (*interConn, error) { if !isActive(c.session) { return nil, errSessionClosed } stream, err := c.session.OpenStream() if err != nil { return nil, err } conn := &interConn{ stream: stream, local: c.session.LocalAddr(), remote: destAddr, } return conn, nil } type clientSessions struct { access sync.Mutex sessions map[net.Destination][]*sessionContext cleanup *task.Periodic } func isActive(s quic.Session) bool { select { case <-s.Context().Done(): return false default: return true } } func removeInactiveSessions(sessions []*sessionContext) []*sessionContext { activeSessions := make([]*sessionContext, 0, len(sessions)) for _, s := range sessions { if isActive(s.session) { activeSessions = append(activeSessions, s) continue } if err := s.session.CloseWithError(0, ""); err != nil { newError("failed to close session").Base(err).WriteToLog() } if err := s.rawConn.Close(); err != nil { newError("failed to close raw connection").Base(err).WriteToLog() } } if len(activeSessions) < len(sessions) { return activeSessions } return sessions } func openStream(sessions []*sessionContext, destAddr net.Addr) *interConn { for _, s := range sessions { if !isActive(s.session) { continue } conn, err := s.openStream(destAddr) if err != nil { continue } return conn } return nil } func (s *clientSessions) cleanSessions() error { s.access.Lock() defer s.access.Unlock() if len(s.sessions) == 0 { return nil } newSessionMap := make(map[net.Destination][]*sessionContext) for dest, sessions := range s.sessions { sessions = removeInactiveSessions(sessions) if len(sessions) > 0 { newSessionMap[dest] = sessions } } s.sessions = newSessionMap return nil } func (s *clientSessions) openConnection(destAddr net.Addr, config *Config, tlsConfig *tls.Config, sockopt *internet.SocketConfig) (internet.Connection, error) { s.access.Lock() defer s.access.Unlock() if s.sessions == nil { s.sessions = make(map[net.Destination][]*sessionContext) } dest := net.DestinationFromAddr(destAddr) var sessions []*sessionContext if s, found := s.sessions[dest]; found { sessions = s } if true { conn := openStream(sessions, destAddr) if conn != nil { return conn, nil } } sessions = removeInactiveSessions(sessions) rawConn, err := internet.ListenSystemPacket(context.Background(), &net.UDPAddr{ IP: []byte{0, 0, 0, 0}, Port: 0, }, sockopt) if err != nil { return nil, err } quicConfig := &quic.Config{ ConnectionIDLength: 12, KeepAlive: true, } conn, err := wrapSysConn(rawConn, config) if err != nil { rawConn.Close() return nil, err } session, err := quic.DialContext(context.Background(), conn, destAddr, "", tlsConfig.GetTLSConfig(tls.WithDestination(dest)), quicConfig) if err != nil { conn.Close() return nil, err } context := &sessionContext{ session: session, rawConn: conn, } s.sessions[dest] = append(sessions, context) return context.openStream(destAddr) } var client clientSessions func init() { client.sessions = make(map[net.Destination][]*sessionContext) client.cleanup = &task.Periodic{ Interval: time.Minute, Execute: client.cleanSessions, } common.Must(client.cleanup.Start()) } func Dial(ctx context.Context, dest net.Destination, streamSettings *internet.MemoryStreamConfig) (internet.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(destAddr, config, tlsConfig, streamSettings.SocketSettings) } func init() { common.Must(internet.RegisterTransportDialer(protocolName, Dial)) }