From 39847cda73d8e8536300b74d90d01b6e2f233ef7 Mon Sep 17 00:00:00 2001 From: Ondrej Zajicek Date: Thu, 23 Dec 2010 12:24:40 +0100 Subject: Add some comments. --- proto/ospf/rt.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'proto/ospf/rt.c') diff --git a/proto/ospf/rt.c b/proto/ospf/rt.c index 6b8886ba..5469bdcf 100644 --- a/proto/ospf/rt.c +++ b/proto/ospf/rt.c @@ -517,6 +517,13 @@ link_back(struct ospf_area *oa, struct top_hash_entry *en, struct top_hash_entry if (!en || !par) return 0; + /* We should check whether there is a link back from en to par, + this is used in SPF calc (RFC 2328 16.1. (2b)). According to RFC 2328 + note 23, we don't have to find the same link that is used for par + to en, any link is enough. This we do for ptp links. For net-rt + links, we have to find the same link to compute proper lb/lb_id, + which may be later used as the next hop. */ + /* In OSPFv2, en->lb is set here. In OSPFv3, en->lb is just cleared here, it is set in process_prefixes() to any global addres in the area */ @@ -556,6 +563,7 @@ link_back(struct ospf_area *oa, struct top_hash_entry *en, struct top_hash_entry break; case LSART_VLNK: case LSART_PTP: + /* Not necessary the same link, see RFC 2328 [23] */ tmp = ospf_hash_find_rt(po->gr, oa->areaid, rtl->id); if (tmp == par) return 1; -- cgit v1.2.3