Babel: Set onlink flag for IPv4 routes with unreachable next hop

If the next hop of a route is not a reachable address, the route should be
installed as onlink. This enables a configuration common in mesh networks
where the mesh interface is assigned a /32 and babel handles the routing by
installing onlink routes.

Thanks to Toke Hoiland-Jorgensen for the patch.
This commit is contained in:
Ondrej Zajicek (work) 2020-05-26 23:43:13 +02:00
parent c1632ad0f3
commit 4e8f8afc68

View file

@ -640,6 +640,14 @@ babel_announce_rte(struct babel_proto *p, struct babel_entry *e)
.nh.iface = r->neigh->ifa->iface, .nh.iface = r->neigh->ifa->iface,
}; };
/*
* If we cannot find a reachable neighbour, set the entry to be onlink. This
* makes it possible to, e.g., assign /32 addresses on a mesh interface and
* have routing work.
*/
if (!neigh_find(&p->p, r->next_hop, r->neigh->ifa->iface, 0))
a0.nh.flags = RNF_ONLINK;
rta *a = rta_lookup(&a0); rta *a = rta_lookup(&a0);
rte *rte = rte_get_temp(a); rte *rte = rte_get_temp(a);
rte->u.babel.seqno = r->seqno; rte->u.babel.seqno = r->seqno;