From aed7cc626d4056f6850d906c2c73abf45934a875 Mon Sep 17 00:00:00 2001
From: Chirag Shah <chirag@cumulusnetworks.com>
Date: Tue, 21 Nov 2017 20:57:50 -0800
Subject: [PATCH] ospfd: Forward reference ospf area config

Upon restart frr interface configuration applied
prior to 'router ospf' configuration. 'ip ospf area x'
config fails if ospf instance is not active.

Allow 'ip ospf area x' configuration to allow in absence
of ospf instance. Upon 'router ospf' walk through vrf
aware interfaces, active area cofigurations.
When vrf is enabled, router-id update also walk through
vrf aware interfaces to enable area configuration
via network_run_interface.

Ticket: CM-18927
Reviewed By:
Testing Done:
Configured multiple interfaces with 'ip ospf area x'
with multiple areas/interface combinations.
Upon router ospf enable along with vrf is active,
interfaces comes up in respective area, ospf neighborship
comes up fine.

Signed-off-by: Chirag Shah <chirag@cumulusnetworks.com>
---
 ospfd/ospf_vty.c | 57 +++++++++++++++++++++++++++++++++++++++++-------
 ospfd/ospfd.h    |  4 +++-
 2 files changed, 52 insertions(+), 9 deletions(-)

diff --git a/ospfd/ospf_vty.c b/ospfd/ospf_vty.c
index a49143873e..f76ae8f698 100644
--- a/ospfd/ospf_vty.c
+++ b/ospfd/ospf_vty.c
@@ -201,6 +201,9 @@ DEFUN_NOSH (router_ospf,
 	struct ospf *ospf = NULL;
 	int ret = CMD_SUCCESS;
 	u_short instance = 0;
+	struct vrf *vrf = NULL;
+	struct route_node *rn;
+	struct interface *ifp;
 
 	ospf = ospf_cmd_lookup_ospf(vty, argv, argc, 1, &instance);
 	if (!ospf)
@@ -219,6 +222,34 @@ DEFUN_NOSH (router_ospf,
 				   instance,  ospf->name ? ospf->name : "NIL",
 				   ospf->vrf_id, ospf->oi_running);
 		VTY_PUSH_CONTEXT(OSPF_NODE, ospf);
+
+		/* Activate 'ip ospf area x' configured interfaces for given
+		 * vrf. Activate area on vrf x aware interfaces.
+		 * vrf_enable callback calls router_id_update which
+		 * internally will call ospf_if_update to trigger
+		 * network_run_state
+		 */
+		vrf = vrf_lookup_by_id(ospf->vrf_id);
+
+		FOR_ALL_INTERFACES (vrf, ifp) {
+			struct ospf_if_params *params;
+
+			params = IF_DEF_PARAMS(ifp);
+			if (OSPF_IF_PARAM_CONFIGURED(params, if_area)) {
+				for (rn = route_top(ospf->networks); rn;
+				     rn = route_next(rn)) {
+					if (rn->info != NULL) {
+						vty_out(vty,
+						"Interface %s has area config but please remove all network commands first.\n",
+						ifp->name);
+						return ret;
+					}
+				}
+				ospf_interface_area_set(ospf, ifp);
+				ospf->if_ospf_cli_count++;
+			}
+		}
+
 		ospf_router_id_update(ospf);
 	}
 
@@ -570,6 +601,11 @@ DEFUN (ospf_network_area,
 	if (ospf->if_ospf_cli_count > 0) {
 		vty_out(vty,
 			"Please remove all ip ospf area x.x.x.x commands first.\n");
+		if (IS_DEBUG_OSPF_EVENT)
+			zlog_debug("%s ospf vrf %s num of %u ip osp area x config",
+				   __PRETTY_FUNCTION__,
+				   ospf->name ? ospf->name : "NIL",
+				   ospf->if_ospf_cli_count);
 		return CMD_WARNING_CONFIG_FAILED;
 	}
 
@@ -7926,7 +7962,7 @@ DEFUN (ip_ospf_area,
 	else
 		ospf = ospf_lookup_instance(instance);
 
-	if (ospf == NULL) {
+	if (instance && ospf == NULL) {
 		params = IF_DEF_PARAMS(ifp);
 		if (OSPF_IF_PARAM_CONFIGURED(params, if_area)) {
 			UNSET_IF_PARAM(params, if_area);
@@ -7971,11 +8007,13 @@ DEFUN (ip_ospf_area,
 		ospf_if_update_params((ifp), (addr));
 	}
 
-	for (rn = route_top(ospf->networks); rn; rn = route_next(rn)) {
-		if (rn->info != NULL) {
-			vty_out(vty,
-				"Please remove all network commands first.\n");
-			return CMD_WARNING_CONFIG_FAILED;
+	if (ospf) {
+		for (rn = route_top(ospf->networks); rn; rn = route_next(rn)) {
+			if (rn->info != NULL) {
+				vty_out(vty,
+					"Please remove all network commands first.\n");
+				return CMD_WARNING_CONFIG_FAILED;
+			}
 		}
 	}
 
@@ -7985,8 +8023,11 @@ DEFUN (ip_ospf_area,
 		params->if_area = area_id;
 		params->if_area_id_fmt = format;
 	}
-	ospf_interface_area_set(ospf, ifp);
-	ospf->if_ospf_cli_count++;
+
+	if (ospf) {
+		ospf_interface_area_set(ospf, ifp);
+		ospf->if_ospf_cli_count++;
+	}
 
 	return CMD_SUCCESS;
 }
diff --git a/ospfd/ospfd.h b/ospfd/ospfd.h
index 6cccccc649..fbe08e913c 100644
--- a/ospfd/ospfd.h
+++ b/ospfd/ospfd.h
@@ -305,7 +305,9 @@ struct ospf {
 	/* Statistics for LSA used for new instantiation. */
 	u_int32_t rx_lsa_count;
 
-	/* Counter of "ip ospf area x.x.x.x" */
+	/* Counter of "ip ospf area x.x.x.x" used
+	 * for multual exclusion of network command under
+	 * router ospf or ip ospf area x under interface. */
 	u_int32_t if_ospf_cli_count;
 
 	struct route_table *distance_table;
-- 
2.39.5