extern void subnet_add(struct node_t *, subnet_t *);
extern void subnet_del(struct node_t *, subnet_t *);
extern void subnet_update(struct node_t *, subnet_t *, bool);
extern void subnet_add(struct node_t *, subnet_t *);
extern void subnet_del(struct node_t *, subnet_t *);
extern void subnet_update(struct node_t *, subnet_t *, bool);