ospf6d: fix interface area configuration

Currently the interface area is configured from the router node using
"interface IFNAME area ID" command. There are multiple problems with
this command:
- it is not in line with all other interface-related commands - other
  parameters are configured from the interface node using "ipv6 ospf6"
  prefix
- it is not in line with OSPFv2 - area is configured from the interface
  node using "ip ospf area" command
- most importantly, it doesn't work correctly when the interface is in
  a different VRF - instead of configuring the interface, it creates a
  new fake interface and configuring it instead

To fix all the problems, this commit adds a new command to the interface
configuration node - "ipv6 ospf6 area ID". The purpose of the command is
completely the same, but it works correctly in a multi-VRF environment.

The old command is preserved for the backward compatibility, but the
warning is added that it is deprecated because it doesn't work correctly
with VRFs.

Signed-off-by: Igor Ryzhov <iryzhov@nfware.com>

1 files changed, 151 insertions, 26 deletions

diff --git a/ospf6d/ospf6_interface.c b/ospf6d/ospf6_interface.c
index b71d884fdc..148f2dc50d 100644
--- a/ospf6d/ospf6_interface.c
+++ b/ospf6d/ospf6_interface.c
@@ -36,6 +36,7 @@
 #include "ospf6_message.h"
 #include "ospf6_route.h"
 #include "ospf6_area.h"
+#include "ospf6_abr.h"
 #include "ospf6_interface.h"
 #include "ospf6_neighbor.h"
 #include "ospf6_intra.h"
@@ -330,31 +331,6 @@ ospf6_interface_get_linklocal_address(struct interface *ifp)
 	return l;
 }
 
-void ospf6_interface_if_add(struct interface *ifp)
-{
-	struct ospf6_interface *oi;
-	unsigned int iobuflen;
-
-	oi = (struct ospf6_interface *)ifp->info;
-	if (oi == NULL)
-		return;
-
-	/* Try to adjust I/O buffer size with IfMtu */
-	if (oi->ifmtu == 0)
-		oi->ifmtu = ifp->mtu6;
-	iobuflen = ospf6_iobuf_size(ifp->mtu6);
-	if (oi->ifmtu > iobuflen) {
-		if (IS_OSPF6_DEBUG_INTERFACE)
-			zlog_debug(
-				"Interface %s: IfMtu is adjusted to I/O buffer size: %d.",
-				ifp->name, iobuflen);
-		oi->ifmtu = iobuflen;
-	}
-
-	/* interface start */
-	ospf6_interface_state_update(oi->interface);
-}
-
 void ospf6_interface_state_update(struct interface *ifp)
 {
 	struct ospf6_interface *oi;
@@ -1638,7 +1614,143 @@ DEFUN(show_ipv6_ospf6_interface_prefix, show_ipv6_ospf6_interface_prefix_cmd,
 	return CMD_SUCCESS;
 }
 
+void ospf6_interface_start(struct ospf6_interface *oi)
+{
+	struct ospf6 *ospf6;
+	struct ospf6_area *oa;
+
+	if (oi->area_id_format == OSPF6_AREA_FMT_UNSET)
+		return;
+
+	ospf6 = ospf6_lookup_by_vrf_id(oi->interface->vrf_id);
+	if (!ospf6)
+		return;
+
+	oa = ospf6_area_lookup(oi->area_id, ospf6);
+	if (oa == NULL)
+		oa = ospf6_area_create(oi->area_id, ospf6, oi->area_id_format);
+
+	/* attach interface to area */
+	listnode_add(oa->if_list, oi);
+	oi->area = oa;
+
+	SET_FLAG(oa->flag, OSPF6_AREA_ENABLE);
+
+	/* start up */
+	ospf6_interface_enable(oi);
+
+	/* If the router is ABR, originate summary routes */
+	if (ospf6_is_router_abr(ospf6))
+		ospf6_abr_enable_area(oa);
+}
+
+void ospf6_interface_stop(struct ospf6_interface *oi)
+{
+	struct ospf6_area *oa;
+
+	oa = oi->area;
+	if (!oa)
+		return;
+
+	ospf6_interface_disable(oi);
+
+	listnode_delete(oa->if_list, oi);
+	oi->area = NULL;
+
+	if (oa->if_list->count == 0) {
+		UNSET_FLAG(oa->flag, OSPF6_AREA_ENABLE);
+		ospf6_abr_disable_area(oa);
+	}
+}
+
 /* interface variable set command */
+DEFUN (ipv6_ospf6_area,
+       ipv6_ospf6_area_cmd,
+       "ipv6 ospf6 area <A.B.C.D|(0-4294967295)>",
+       IP6_STR
+       OSPF6_STR
+       "Specify the OSPF6 area ID\n"
+       "OSPF6 area ID in IPv4 address notation\n"
+       "OSPF6 area ID in decimal notation\n")
+{
+	VTY_DECLVAR_CONTEXT(interface, ifp);
+	struct ospf6_interface *oi;
+	int idx_ipv4 = 3;
+	uint32_t area_id;
+	int format;
+	int ipv6_count = 0;
+
+	assert(ifp);
+
+	oi = (struct ospf6_interface *)ifp->info;
+	if (oi == NULL)
+		oi = ospf6_interface_create(ifp);
+	assert(oi);
+
+	if (oi->area) {
+		vty_out(vty, "%s already attached to Area %s\n",
+			oi->interface->name, oi->area->name);
+		return CMD_SUCCESS;
+	}
+
+	/* if more than OSPF6_MAX_IF_ADDRS are configured on this interface
+	 * then don't allow ospfv3 to be configured
+	 */
+	ipv6_count = connected_count_by_family(ifp, AF_INET6);
+	if (oi->ifmtu == OSPF6_DEFAULT_MTU && ipv6_count > OSPF6_MAX_IF_ADDRS) {
+		vty_out(vty,
+			"can not configure OSPFv3 on if %s, must have less than %d interface addresses but has %d addresses\n",
+			ifp->name, OSPF6_MAX_IF_ADDRS, ipv6_count);
+		return CMD_WARNING_CONFIG_FAILED;
+	} else if (oi->ifmtu >= OSPF6_JUMBO_MTU
+		   && ipv6_count > OSPF6_MAX_IF_ADDRS_JUMBO) {
+		vty_out(vty,
+			"can not configure OSPFv3 on if %s, must have less than %d interface addresses but has %d addresses\n",
+			ifp->name, OSPF6_MAX_IF_ADDRS_JUMBO, ipv6_count);
+		return CMD_WARNING_CONFIG_FAILED;
+	}
+
+	if (str2area_id(argv[idx_ipv4]->arg, &area_id, &format)) {
+		vty_out(vty, "Malformed Area-ID: %s\n", argv[idx_ipv4]->arg);
+		return CMD_WARNING_CONFIG_FAILED;
+	}
+
+	oi->area_id = area_id;
+	oi->area_id_format = format;
+
+	ospf6_interface_start(oi);
+
+	return CMD_SUCCESS;
+}
+
+DEFUN (no_ipv6_ospf6_area,
+       no_ipv6_ospf6_area_cmd,
+       "no ipv6 ospf6 area [<A.B.C.D|(0-4294967295)>]",
+       NO_STR
+       IP6_STR
+       OSPF6_STR
+       "Specify the OSPF6 area ID\n"
+       "OSPF6 area ID in IPv4 address notation\n"
+       "OSPF6 area ID in decimal notation\n")
+{
+	VTY_DECLVAR_CONTEXT(interface, ifp);
+	struct ospf6_interface *oi;
+
+	assert(ifp);
+
+	oi = (struct ospf6_interface *)ifp->info;
+	if (oi == NULL)
+		oi = ospf6_interface_create(ifp);
+	assert(oi);
+
+	ospf6_interface_stop(oi);
+
+	oi->area_id = 0;
+	oi->area_id_format = OSPF6_AREA_FMT_UNSET;
+
+	return CMD_SUCCESS;
+}
+
 DEFUN (ipv6_ospf6_ifmtu,
        ipv6_ospf6_ifmtu_cmd,
        "ipv6 ospf6 ifmtu (1-65535)",
@@ -2334,6 +2446,7 @@ static int config_write_ospf6_interface(struct vty *vty, struct vrf *vrf)
 {
 	struct ospf6_interface *oi;
 	struct interface *ifp;
+	char buf[INET_ADDRSTRLEN];
 
 	FOR_ALL_INTERFACES (vrf, ifp) {
 		oi = (struct ospf6_interface *)ifp->info;
@@ -2348,6 +2461,11 @@ static int config_write_ospf6_interface(struct vty *vty, struct vrf *vrf)
 
 		if (ifp->desc)
 			vty_out(vty, " description %s\n", ifp->desc);
+		if (oi->area_id_format != OSPF6_AREA_FMT_UNSET) {
+			area_id2str(buf, sizeof(buf), oi->area_id,
+				    oi->area_id_format);
+			vty_out(vty, " ipv6 ospf6 area %s\n", buf);
+		}
 		if (oi->c_ifmtu)
 			vty_out(vty, " ipv6 ospf6 ifmtu %d\n", oi->c_ifmtu);
 
@@ -2427,7 +2545,9 @@ static int ospf6_ifp_create(struct interface *ifp)
 	if (IS_OSPF6_DEBUG_ZEBRA(RECV))
 		zlog_debug("Zebra Interface add: %s index %d mtu %d", ifp->name,
 			   ifp->ifindex, ifp->mtu6);
-	ospf6_interface_if_add(ifp);
+
+	if (ifp->info)
+		ospf6_interface_start(ifp->info);
 
 	return 0;
 }
@@ -2468,6 +2588,9 @@ static int ospf6_ifp_destroy(struct interface *ifp)
 		zlog_debug("Zebra Interface delete: %s index %d mtu %d",
 			   ifp->name, ifp->ifindex, ifp->mtu6);
 
+	if (ifp->info)
+		ospf6_interface_stop(ifp->info);
+
 	return 0;
 }
 
@@ -2485,6 +2608,8 @@ void ospf6_interface_init(void)
 			&show_ipv6_ospf6_interface_ifname_prefix_cmd);
 	install_element(VIEW_NODE, &show_ipv6_ospf6_interface_traffic_cmd);
 
+	install_element(INTERFACE_NODE, &ipv6_ospf6_area_cmd);
+	install_element(INTERFACE_NODE, &no_ipv6_ospf6_area_cmd);
 	install_element(INTERFACE_NODE, &ipv6_ospf6_cost_cmd);
 	install_element(INTERFACE_NODE, &no_ipv6_ospf6_cost_cmd);
 	install_element(INTERFACE_NODE, &ipv6_ospf6_ifmtu_cmd);