OSPF: Packets on PtP networks should be always sent to AllSPFRouters

As specified in RFC 2328 8.1: "On physical point-to-point networks,
the IP destination is always set to the address AllSPFRouters."

Note that this likely break setups with multiple neighbors on a network
configured as PtP, which worked before. These should be configured as
PtMP.

Thanks to Senthil Kumar Nagappan for the original patch and to Joakim
Tjernlund for suggestions.

1 files changed, 3 insertions, 0 deletions

diff --git a/proto/ospf/ospf.h b/proto/ospf/ospf.h
index aa7d937e..fd2347e5 100644
--- a/proto/ospf/ospf.h
+++ b/proto/ospf/ospf.h
@@ -1058,6 +1058,9 @@ void ospf_verr_hook(sock *sk, int err);
 void ospf_send_to(struct ospf_iface *ifa, ip_addr ip);
 void ospf_send_to_iface(struct ospf_iface *ifa);
 
+static inline void ospf_send_to_nbr(struct ospf_iface *ifa, struct ospf_neighbor *n)
+{ ospf_send_to(ifa, (ifa->type == OSPF_IT_PTP) ? ifa->all_routers :  n->ip); }
+
 static inline void ospf_send_to_all(struct ospf_iface *ifa)
 { ospf_send_to(ifa, ifa->all_routers); }