typedef void *(*handle_upper_udp_dun_t)(uint8_t);
/* Handles UDP-packets that are detected by any network layer. */
-extern int8_t handle_udp(int fd, uint8_t * udp_packet, int32_t packetsize);
+extern int8_t handle_udp(int fd, uint8_t * udp_packet, uint32_t packetsize);
/* Handles UDP related ICMP-Dest.Unreachable packets that are detected by
* the network layers. */