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 { defer packet.Drop() 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 func() { _ = pc.Close() natTable.Delete(key) _ = pool.Put(buf) }() for { _ = pc.SetReadDeadline(time.Now().Add(udpTimeout)) n, from, err := pc.ReadFrom(buf) if err != nil { return } fromUDPAddr := from.(*net.UDPAddr) fromUDPAddr = &(*fromUDPAddr) // make a copy if fromAddr, ok := netip.AddrFromSlice(fromUDPAddr.IP); ok { if fAddr.IsValid() && (oAddr.Unmap() == fromAddr.Unmap()) { fromUDPAddr.IP = fAddr.Unmap().AsSlice() } else { fromUDPAddr.IP = fromAddr.Unmap().AsSlice() } } _, err = packet.WriteBack(buf[:n], fromUDPAddr) if err != nil { return } } } func handleSocket(ctx C.ConnContext, outbound net.Conn) { N.Relay(ctx.Conn(), outbound) }