package tunnel import ( "errors" "net" "net/netip" "time" N "github.com/Dreamacro/clash/common/net" "github.com/Dreamacro/clash/common/pool" C "github.com/Dreamacro/clash/constant" ) func handleUDPToRemote(packet C.UDPPacket, pc C.PacketConn, metadata *C.Metadata) error { addr := metadata.UDPAddr() if addr == nil { return errors.New("udp addr invalid") } if _, err := pc.WriteTo(packet.Data(), addr); err != nil { return err } // reset timeout pc.SetReadDeadline(time.Now().Add(udpTimeout)) return nil } func handleUDPToLocal(packet C.UDPPacket, pc net.PacketConn, key string, oAddr, fAddr netip.Addr) { buf := pool.Get(pool.UDPBufferSize) defer pool.Put(buf) defer natTable.Delete(key) defer pc.Close() for { pc.SetReadDeadline(time.Now().Add(udpTimeout)) n, from, err := pc.ReadFrom(buf) if err != nil { return } fromUDPAddr := *from.(*net.UDPAddr) if fAddr.IsValid() { fromAddr, _ := netip.AddrFromSlice(fromUDPAddr.IP) fromAddr = fromAddr.Unmap() if oAddr == fromAddr { fromUDPAddr.IP = fAddr.AsSlice() } } _, err = packet.WriteBack(buf[:n], &fromUDPAddr) if err != nil { return } } } func handleSocket(ctx C.ConnContext, outbound net.Conn) { N.Relay(ctx.Conn(), outbound) }