rem: if (find_match(me->name, DONT_LOAD, NULL)) { fprintf(stderr, "%s: match `%s' already registered.\n",
add: if (!memchr(me->name, 0, IPT_FUNCTION_MAXNAMELEN-1)) { fprintf(stderr, "%s: target `%s' has invalid name\n",
context: register_match(struct iptables_match *me){	struct iptables_match **i;	if (strcmp(me->version, program_version) != 0) {		fprintf(stderr, "%s: match `%s' v%s (I'm v%s).\n",			program_name, me->name, me->version, program_version);		exit(1);	}	if (find_match(me->name, DONT_LOAD, NULL)) {		fprintf(stderr, "%s: match `%s' already registered.\n",			program_name, me->name);		exit(1);	}	if (me->size != IPT_ALIGN(me->size)) {		fprintf(stderr, "%s: match `%s' has invalid size %u.\n",			program_name, me->name, (unsigned int)me->size);		exit(1);	}	/* Append to list. */	for (i = &iptables_matches; *i; i = &(*i)->next);	me->next = NULL;	*i = me;	me->m = NULL;	me->mflags = 0;}