Refresh kernel protocol when interface disappears.

When an interface goes down, (Linux) kernel removes routes pointing to
that ifacem but does not send withdraws for them. We rescan the
kernel table to ensure synchronization.

Thanks to Alexander Demenshin for the bugreport.
This commit is contained in:
Ondrej Zajicek 2014-10-02 11:05:55 +02:00
parent b2f008378a
commit 252c7e4d0b

View file

@ -910,7 +910,7 @@ krt_scan_timer_stop(struct krt_proto *p)
} }
static void static void
krt_scan_timer_kick(struct krt_proto *p UNUSED) krt_scan_timer_kick(struct krt_proto *p)
{ {
tm_start(p->scan_timer, 0); tm_start(p->scan_timer, 0);
} }
@ -974,8 +974,8 @@ krt_import_control(struct proto *P, rte **new, ea_list **attrs, struct linpool *
} }
static void static void
krt_notify(struct proto *P, struct rtable *table UNUSED, net *net, krt_rt_notify(struct proto *P, struct rtable *table UNUSED, net *net,
rte *new, rte *old, struct ea_list *eattrs) rte *new, rte *old, struct ea_list *eattrs)
{ {
struct krt_proto *p = (struct krt_proto *) P; struct krt_proto *p = (struct krt_proto *) P;
@ -991,6 +991,36 @@ krt_notify(struct proto *P, struct rtable *table UNUSED, net *net,
krt_replace_rte(p, net, new, old, eattrs); krt_replace_rte(p, net, new, old, eattrs);
} }
static void
krt_if_notify(struct proto *P, uint flags, struct iface *iface UNUSED)
{
struct krt_proto *p = (struct krt_proto *) P;
/*
* When interface went down, we should remove routes to it. In the ideal world,
* OS kernel would send us route removal notifications in such cases, but we
* cannot rely on it as it is often not true. E.g. Linux kernel removes related
* routes when an interface went down, but it does not notify userspace about
* that. To be sure, we just schedule a scan to ensure synchronization.
*/
if ((flags & IF_CHANGE_DOWN) && KRT_CF->learn)
krt_scan_timer_kick(p);
}
static int
krt_reload_routes(struct proto *P)
{
struct krt_proto *p = (struct krt_proto *) P;
/* Although we keep learned routes in krt_table, we rather schedule a scan */
if (KRT_CF->learn)
krt_scan_timer_kick(p);
return 1;
}
static void static void
krt_feed_done(struct proto *P) krt_feed_done(struct proto *P)
{ {
@ -1022,7 +1052,9 @@ krt_init(struct proto_config *c)
p->p.accept_ra_types = RA_OPTIMAL; p->p.accept_ra_types = RA_OPTIMAL;
p->p.import_control = krt_import_control; p->p.import_control = krt_import_control;
p->p.rt_notify = krt_notify; p->p.rt_notify = krt_rt_notify;
p->p.if_notify = krt_if_notify;
p->p.reload_routes = krt_reload_routes;
p->p.feed_done = krt_feed_done; p->p.feed_done = krt_feed_done;
p->p.make_tmp_attrs = krt_make_tmp_attrs; p->p.make_tmp_attrs = krt_make_tmp_attrs;
p->p.store_tmp_attrs = krt_store_tmp_attrs; p->p.store_tmp_attrs = krt_store_tmp_attrs;