add: if (me->size != IPT_ALIGN(me->size)) { fprintf(stderr, "%s: match `%s' has invalid size %u.\n", program_name, me->name, me->size); exit(1); }
context: register_match(struct iptables_match *me){	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)) {		fprintf(stderr, "%s: match `%s' already registered.\n",			program_name, me->name);		exit(1);	}	/* Prepend to list. */	me->next = iptables_matches;	iptables_matches = me;	me->m = NULL;	me->mflags = 0;	opts = merge_options(opts, me->extra_opts, &me->option_offset);}