zebra: Add interface sysctl ignore on linkdown status

Add the ability to decode the ignore on linkdown nexthop
status for an interface.

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

zebra/interface.c

@@ -1407,7 +1407,7 @@ static void zebra_if_netconf_update_ctx(struct zebra_dplane_ctx *ctx,
 					struct interface *ifp)
 {
 	struct zebra_if *zif;
-	enum dplane_netconf_status_e mpls;
+	enum dplane_netconf_status_e mpls, linkdown;
 
 	zif = ifp->info;
 	if (!zif) {
@@ -1424,10 +1424,17 @@ static void zebra_if_netconf_update_ctx(struct zebra_dplane_ctx *ctx,
 	else if (mpls == DPLANE_NETCONF_STATUS_DISABLED)
 		zif->mpls = false;
 
+	linkdown = dplane_ctx_get_netconf_linkdown(ctx);
+	if (linkdown == DPLANE_NETCONF_STATUS_ENABLED)
+		zif->linkdown = true;
+	else if (linkdown == DPLANE_NETCONF_STATUS_DISABLED)
+		zif->linkdown = false;
+
 	if (IS_ZEBRA_DEBUG_KERNEL)
-		zlog_debug("%s: if %s, ifindex %d, mpls %s",
+		zlog_debug("%s: if %s, ifindex %d, mpls %s linkdown %s",
 			   __func__, ifp->name, ifp->ifindex,
-			   (zif->mpls ? "ON" : "OFF"));
+			   (zif->mpls ? "ON" : "OFF"),
+			   (zif->linkdown ? "ON" : "OFF"));
 }
 
 void zebra_if_dplane_result(struct zebra_dplane_ctx *ctx)
@@ -1890,6 +1897,9 @@ static void if_dump_vty(struct vty *vty, struct interface *ifp)
 	if (zebra_if->mpls)
 		vty_out(vty, "  MPLS enabled\n");
 
+	if (zebra_if->linkdown)
+		vty_out(vty, "  Ignore all routes with linkdown\n");
+
 	/* Hardware address. */
 	vty_out(vty, "  Type: %s\n", if_link_type_str(ifp->ll_type));
 	if (ifp->hw_addr_len != 0) {
@@ -2211,6 +2221,7 @@ static void if_dump_vty_json(struct vty *vty, struct interface *ifp,
 				       zebra_if->desc);
 
 	json_object_boolean_add(json_if, "mplsEnabled", zebra_if->mpls);
+	json_object_boolean_add(json_if, "linkDown", zebra_if->linkdown);
 
 	if (ifp->ifindex == IFINDEX_INTERNAL) {
 		json_object_boolean_add(json_if, "pseudoInterface", true);

zebra/interface.h

@@ -129,6 +129,9 @@ struct zebra_if {
 	/* MPLS status. */
 	bool mpls;
 
+	/* Linkdown status */
+	bool linkdown;
+
 	/* Router advertise configuration. */
 	uint8_t rtadv_enable;
 

zebra/netconf_netlink.c

@@ -45,9 +45,11 @@ static struct rtattr *netconf_rta(struct netconfmsg *ncm)
  * Handle netconf update about a single interface: create dplane
  * context, and enqueue for processing in the main zebra pthread.
  */
-static int netlink_netconf_dplane_update(ns_id_t ns_id, ifindex_t ifindex,
+static int
-					 enum dplane_netconf_status_e mpls_on,
+netlink_netconf_dplane_update(ns_id_t ns_id, ifindex_t ifindex,
-					 enum dplane_netconf_status_e mcast_on)
+			      enum dplane_netconf_status_e mpls_on,
+			      enum dplane_netconf_status_e mcast_on,
+			      enum dplane_netconf_status_e linkdown_on)
 {
 	struct zebra_dplane_ctx *ctx;
 
@@ -58,6 +60,7 @@ static int netlink_netconf_dplane_update(ns_id_t ns_id, ifindex_t ifindex,
 
 	dplane_ctx_set_netconf_mpls(ctx, mpls_on);
 	dplane_ctx_set_netconf_mcast(ctx, mcast_on);
+	dplane_ctx_set_netconf_linkdown(ctx, linkdown_on);
 
 	/* Enqueue ctx for main pthread to process */
 	dplane_provider_enqueue_to_zebra(ctx);
@@ -77,6 +80,8 @@ int netlink_netconf_change(struct nlmsghdr *h, ns_id_t ns_id, int startup)
 	uint32_t ival;
 	enum dplane_netconf_status_e mpls_on = DPLANE_NETCONF_STATUS_UNKNOWN;
 	enum dplane_netconf_status_e mcast_on = DPLANE_NETCONF_STATUS_UNKNOWN;
+	enum dplane_netconf_status_e linkdown_on =
+		DPLANE_NETCONF_STATUS_UNKNOWN;
 
 	if (h->nlmsg_type != RTM_NEWNETCONF && h->nlmsg_type != RTM_DELNETCONF)
 		return 0;
@@ -133,12 +138,23 @@ int netlink_netconf_change(struct nlmsghdr *h, ns_id_t ns_id, int startup)
 			mcast_on = DPLANE_NETCONF_STATUS_DISABLED;
 	}
 
+	if (tb[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]) {
+		ival = *(uint32_t *)RTA_DATA(
+			tb[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]);
+		if (ival != 0)
+			linkdown_on = DPLANE_NETCONF_STATUS_ENABLED;
+		else
+			linkdown_on = DPLANE_NETCONF_STATUS_DISABLED;
+	}
+
 	if (IS_ZEBRA_DEBUG_KERNEL)
-		zlog_debug("%s: interface %u is mpls on: %d multicast on: %d",
+		zlog_debug(
-			   __func__, ifindex, mpls_on, mcast_on);
+			"%s: interface %u is mpls on: %d multicast on: %d linkdown: %d",
+			__func__, ifindex, mpls_on, mcast_on, linkdown_on);
 
 	/* Create a dplane context and pass it along for processing */
-	netlink_netconf_dplane_update(ns_id, ifindex, mpls_on, mcast_on);
+	netlink_netconf_dplane_update(ns_id, ifindex, mpls_on, mcast_on,
+				      linkdown_on);
 
 	return 0;
 }

zebra/zebra_dplane.c

@@ -303,6 +303,7 @@ struct dplane_gre_ctx {
 struct dplane_netconf_info {
 	enum dplane_netconf_status_e mpls_val;
 	enum dplane_netconf_status_e mcast_val;
+	enum dplane_netconf_status_e linkdown_val;
 };
 
 /*
@@ -2348,6 +2349,14 @@ dplane_ctx_get_netconf_mcast(const struct zebra_dplane_ctx *ctx)
 	return ctx->u.netconf.mcast_val;
 }
 
+enum dplane_netconf_status_e
+dplane_ctx_get_netconf_linkdown(const struct zebra_dplane_ctx *ctx)
+{
+	DPLANE_CTX_VALID(ctx);
+
+	return ctx->u.netconf.linkdown_val;
+}
+
 void dplane_ctx_set_netconf_mpls(struct zebra_dplane_ctx *ctx,
 				 enum dplane_netconf_status_e val)
 {
@@ -2364,6 +2373,15 @@ void dplane_ctx_set_netconf_mcast(struct zebra_dplane_ctx *ctx,
 	ctx->u.netconf.mcast_val = val;
 }
 
+void dplane_ctx_set_netconf_linkdown(struct zebra_dplane_ctx *ctx,
+				     enum dplane_netconf_status_e val)
+{
+	DPLANE_CTX_VALID(ctx);
+
+	ctx->u.netconf.linkdown_val = val;
+}
+
+
 /*
  * Retrieve the limit on the number of pending, unprocessed updates.
  */

zebra/zebra_dplane.h

@@ -596,10 +596,15 @@ enum dplane_netconf_status_e
 dplane_ctx_get_netconf_mpls(const struct zebra_dplane_ctx *ctx);
 enum dplane_netconf_status_e
 dplane_ctx_get_netconf_mcast(const struct zebra_dplane_ctx *ctx);
+enum dplane_netconf_status_e
+dplane_ctx_get_netconf_linkdown(const struct zebra_dplane_ctx *ctx);
+
 void dplane_ctx_set_netconf_mpls(struct zebra_dplane_ctx *ctx,
 				 enum dplane_netconf_status_e val);
 void dplane_ctx_set_netconf_mcast(struct zebra_dplane_ctx *ctx,
 				  enum dplane_netconf_status_e val);
+void dplane_ctx_set_netconf_linkdown(struct zebra_dplane_ctx *ctx,
+				     enum dplane_netconf_status_e val);
 
 /* Namespace fd info - esp. for netlink communication */
 const struct zebra_dplane_info *dplane_ctx_get_ns(