nd6_lookup
ln = nd6_lookup(nexthop, ifp, false);
ln = nd6_lookup(&nb_addr, ifp, false);
ln = nd6_lookup(from, ifp, true);
ln = nd6_lookup(&dst->sin6_addr, ifp, false);
ln = nd6_lookup(&dst->sin6_addr, ifp, true);
ln = nd6_lookup(&addr->sin6_addr, ifp, false);
ln = nd6_lookup(&(satocsin6(rt_getkey(rt)))->sin6_addr, ifp, true);
struct llentry *nd6_lookup(const struct in6_addr *, const struct ifnet *, bool);
ln = nd6_lookup(&taddr6, ifp, true);