From: Piotr Jurkiewicz <piotr.jerzy.jurkiewicz@gmail.com>
Date: Fri, 4 May 2018 00:28:29 +0000 (+0200)
Subject: eigrpd: Consider only feasible successors as successors
X-Git-Tag: frr-6.1-dev~476^2
X-Git-Url: https://git.puffer.fish/?a=commitdiff_plain;h=refs%2Fpull%2F2169%2Fhead;p=mirror%2Ffrr.git

eigrpd: Consider only feasible successors as successors

Meeting the feasibility condition is required also for routes
meeting the variance condition.

Signed-off-by: Piotr Jurkiewicz <piotr.jerzy.jurkiewicz@gmail.com>
---

diff --git a/eigrpd/eigrp_topology.c b/eigrpd/eigrp_topology.c
index 2d1bc46e6b..becb29a95f 100644
--- a/eigrpd/eigrp_topology.c
+++ b/eigrpd/eigrp_topology.c
@@ -443,17 +443,24 @@ void eigrp_topology_update_node_flags(struct eigrp_prefix_entry *dest)
 	struct eigrp *eigrp = eigrp_lookup();
 
 	for (ALL_LIST_ELEMENTS_RO(dest->entries, node, entry)) {
-		if (((uint64_t)entry->distance
-		     <= (uint64_t)dest->distance * (uint64_t)eigrp->variance)
-		    && entry->distance != EIGRP_MAX_METRIC) // is successor
-		{
-			entry->flags |= EIGRP_NEXTHOP_ENTRY_SUCCESSOR_FLAG;
-			entry->flags &= ~EIGRP_NEXTHOP_ENTRY_FSUCCESSOR_FLAG;
-		} else if (entry->reported_distance
-			   < dest->fdistance) // is feasible successor
-		{
-			entry->flags |= EIGRP_NEXTHOP_ENTRY_FSUCCESSOR_FLAG;
-			entry->flags &= ~EIGRP_NEXTHOP_ENTRY_SUCCESSOR_FLAG;
+		if (entry->reported_distance < dest->fdistance) {
+			// is feasible successor, can be successor
+			if (((uint64_t)entry->distance
+			     <= (uint64_t)dest->distance
+					* (uint64_t)eigrp->variance)
+			    && entry->distance != EIGRP_MAX_METRIC) {
+				// is successor
+				entry->flags |=
+					EIGRP_NEXTHOP_ENTRY_SUCCESSOR_FLAG;
+				entry->flags &=
+					~EIGRP_NEXTHOP_ENTRY_FSUCCESSOR_FLAG;
+			} else {
+				// is feasible successor only
+				entry->flags |=
+					EIGRP_NEXTHOP_ENTRY_FSUCCESSOR_FLAG;
+				entry->flags &=
+					~EIGRP_NEXTHOP_ENTRY_SUCCESSOR_FLAG;
+			}
 		} else {
 			entry->flags &= ~EIGRP_NEXTHOP_ENTRY_FSUCCESSOR_FLAG;
 			entry->flags &= ~EIGRP_NEXTHOP_ENTRY_SUCCESSOR_FLAG;