From: Donald Sharp <sharpd@cumulusnetworks.com>
Date: Tue, 22 Aug 2017 18:40:24 +0000 (-0400)
Subject: eigrpd: Start split-horizon
X-Git-Tag: frr-4.0-dev~375^2~17
X-Git-Url: https://git.puffer.fish/?a=commitdiff_plain;h=cd0442479369e53f3b8451163a8679a00f4c0d25;p=matthieu%2Ffrr.git

eigrpd: Start split-horizon

EIGRP was not handling split-horizon.  This code starts
down the path of properly considering it.  There still
exists situations where we are not properly handling it
though.

Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
---

diff --git a/eigrpd/eigrp_neighbor.c b/eigrpd/eigrp_neighbor.c
index d5fc6a2996..5d78dc375c 100644
--- a/eigrpd/eigrp_neighbor.c
+++ b/eigrpd/eigrp_neighbor.c
@@ -357,3 +357,11 @@ void eigrp_nbr_hard_restart(struct eigrp_neighbor *nbr, struct vty *vty)
 	/* delete neighbor */
 	eigrp_nbr_delete(nbr);
 }
+
+int eigrp_nbr_split_horizon_check(struct eigrp_neighbor_entry *ne, struct eigrp_interface *ei)
+{
+	if (ne->distance == EIGRP_MAX_METRIC)
+		return 0;
+
+	return (ne->ei == ei);
+}
diff --git a/eigrpd/eigrp_neighbor.h b/eigrpd/eigrp_neighbor.h
index 006aa9ab75..6467fb24a9 100644
--- a/eigrpd/eigrp_neighbor.h
+++ b/eigrpd/eigrp_neighbor.h
@@ -53,4 +53,6 @@ extern struct eigrp_neighbor *eigrp_nbr_lookup_by_addr_process(struct eigrp *,
 							       struct in_addr);
 extern void eigrp_nbr_hard_restart(struct eigrp_neighbor *nbr, struct vty *vty);
 
+extern int eigrp_nbr_split_horizon_check(struct eigrp_neighbor_entry *ne,
+					 struct eigrp_interface *ei);
 #endif /* _ZEBRA_EIGRP_NEIGHBOR_H */
diff --git a/eigrpd/eigrp_update.c b/eigrpd/eigrp_update.c
index d0c6520c4e..2934c6c652 100644
--- a/eigrpd/eigrp_update.c
+++ b/eigrpd/eigrp_update.c
@@ -610,8 +610,7 @@ void eigrp_update_send_EOT(struct eigrp_neighbor *nbr)
 
 	for (ALL_LIST_ELEMENTS(nbr->ei->eigrp->topology_table, node, nnode, pe)) {
 		for (ALL_LIST_ELEMENTS(pe->entries, node2, nnode2, te)) {
-			if ((te->ei == nbr->ei)
-			    && (te->prefix->nt == EIGRP_TOPOLOGY_TYPE_REMOTE))
+			if (eigrp_nbr_split_horizon_check(te, nbr->ei))
 				continue;
 
 			if ((length + 0x001D) > (u_int16_t)nbr->ei->ifp->mtu) {
@@ -701,10 +700,15 @@ void eigrp_update_send(struct eigrp_interface *ei)
 	has_tlv = 0;
 	for (ALL_LIST_ELEMENTS(ei->eigrp->topology_changes_internalIPV4, node,
 			       nnode, pe)) {
+		struct eigrp_neighbor_entry *ne;
 
 		if (!(pe->req_action & EIGRP_FSM_NEED_UPDATE))
 			continue;
 
+		ne = listnode_head(pe->entries);
+		if (eigrp_nbr_split_horizon_check(ne, ei))
+			continue;
+
 		if ((length + 0x001D) > (u_int16_t)ei->ifp->mtu) {
 			if ((IF_DEF_PARAMS(ei->ifp)->auth_type == EIGRP_AUTH_TYPE_MD5)
 			    && (IF_DEF_PARAMS(ei->ifp)->auth_keychain != NULL)) {