Change unnamed ptp link description on OSPFv2.

Although it is a slight deviation from the standard, it has no ill
consequences for OSPFv2 and the change fixes a compatibility issue
with some broken implementations.

diff --git a/proto/ospf/topology.c b/proto/ospf/topology.c
index bfa071d822fb7e27a8d8d7c7eae164b0a2be1641..5f4d1d5434a1d0fb22ce91683b6d7599deca7307 100644 (file)
--- a/proto/ospf/topology.c
+++ b/proto/ospf/topology.c
@@ -258,8 +258,17 @@ originate_rt_lsa_body(struct ospf_area *oa, u16 *length)
            ln = lsab_alloc(po, sizeof(struct ospf_lsa_rt_link));
            ln->type = LSART_PTP;
            ln->id = neigh->rid;
-           ln->data = (ifa->addr->flags & IA_PEER) ?
-             ifa->iface_id : ipa_to_u32(ifa->addr->ip);
+
+           /*
+            * ln->data should be ifa->iface_id in case of no/ptp
+            * address (ifa->addr->flags & IA_PEER) on PTP link (see
+            * RFC 2328 12.4.1.1.), but the iface ID value has no use,
+            * while using IP address even in this case is here for
+            * compatibility with some broken implementations that use
+            * this address as a next-hop.
+            */
+           ln->data = ipa_to_u32(ifa->addr->ip);
+
            ln->metric = ifa->cost;
            ln->padding = 0;
            i++;