zebra: add 'mpls fec nexthop-resolution' command to vtysh

Commands added:

r3# configure
r3(config)# mpls
  fec    MPLS FEC table
  label  Label configuration
  ldp    Label Distribution Protocol
  lsp    Establish label switched path
r3(config)# mpls fec
  mpls fec nexthop-resolution  Authorise nexthop resolution
				over all labeled routes.
r3(config)# mpls fec mpls fec nexthop-resolution

r3# configure
r3(config)# vrf default
r3(config-vrf)# mpls
  fec  MPLS FEC table
r3(config-vrf)# mpls fec
  mpls fec nexthop-resolution  Authorise nexthop resolution
				over all labeled routes.
r3(config-vrf)# mpls fec nexthop-resolution

east-vm# show running-config
Building configuration...
...
!
mpls fec nexthop-resolution
!
...

Signed-off-by: Dmytro Shytyi <dmytro.shytyi@6wind.com>

8 files changed, 127 insertions, 0 deletions

diff --git a/yang/frr-zebra.yang b/yang/frr-zebra.yang
index 79c524a40a..4aa368e57f 100644
--- a/yang/frr-zebra.yang
+++ b/yang/frr-zebra.yang
@@ -2855,6 +2855,16 @@ module frr-zebra {
         }
       }
 
+      container mpls {
+        description
+          "MPLS Configuration.";
+          leaf fec-nexthop-resolution {
+            type boolean;
+            description
+              "Authorise nexthop resolution over all labeled routes.";
+          }
+      }
+
       uses ribs;
 
       uses vrf-vni-mapping;
diff --git a/zebra/zebra_cli.c b/zebra/zebra_cli.c
index 3e03d74775..6ee0fdbb8d 100644
--- a/zebra/zebra_cli.c
+++ b/zebra/zebra_cli.c
@@ -2221,6 +2221,37 @@ static void lib_vrf_zebra_ipv6_resolve_via_default_cli_write(
 	}
 }
 
+DEFPY_YANG (mpls_fec_nexthop_resolution, mpls_fec_nexthop_resolution_cmd,
+      "[no$no] mpls fec nexthop-resolution",
+      NO_STR
+      MPLS_STR
+      "MPLS FEC table\n"
+      "Authorise nexthop resolution over all labeled routes.\n")
+{
+	nb_cli_enqueue_change(vty,
+			      "./frr-zebra:zebra/mpls/fec-nexthop-resolution",
+			      NB_OP_MODIFY, no ? "false" : "true");
+
+	if (vty->node == CONFIG_NODE)
+		return nb_cli_apply_changes(vty, "/frr-vrf:lib/vrf[name='%s']",
+					    VRF_DEFAULT_NAME);
+
+	return nb_cli_apply_changes(vty, NULL);
+}
+
+static void lib_vrf_mpls_fec_nexthop_resolution_cli_write(
+	struct vty *vty, const struct lyd_node *dnode, bool show_defaults)
+{
+	bool fec_nexthop_resolution = yang_dnode_get_bool(dnode, NULL);
+
+	if (fec_nexthop_resolution || show_defaults) {
+		zebra_vrf_indent_cli_write(vty, dnode);
+
+		vty_out(vty, "%smpls fec nexthop-resolution\n",
+			fec_nexthop_resolution ? "" : "no ");
+	}
+}
+
 DEFPY_YANG (vrf_netns,
        vrf_netns_cmd,
        "[no] netns ![NAME$netns_name]",
@@ -2852,6 +2883,10 @@ const struct frr_yang_module_info frr_zebra_cli_info = {
 			.cbs.cli_show = lib_vrf_zebra_netns_table_range_cli_write,
 		},
 		{
+			.xpath = "/frr-vrf:lib/vrf/frr-zebra:zebra/mpls/fec-nexthop-resolution",
+			.cbs.cli_show = lib_vrf_mpls_fec_nexthop_resolution_cli_write,
+		},
+		{
 			.xpath = "/frr-vrf:lib/vrf/frr-zebra:zebra/l3vni-id",
 			.cbs.cli_show = lib_vrf_zebra_l3vni_id_cli_write,
 		},
@@ -2957,6 +2992,9 @@ void zebra_cli_init(void)
 	install_element(VRF_NODE, &ip_nht_default_route_cmd);
 	install_element(VRF_NODE, &ipv6_nht_default_route_cmd);
 
+	install_element(CONFIG_NODE, &mpls_fec_nexthop_resolution_cmd);
+	install_element(VRF_NODE, &mpls_fec_nexthop_resolution_cmd);
+
 	install_element(CONFIG_NODE, &vni_mapping_cmd);
 	install_element(VRF_NODE, &vni_mapping_cmd);
 
diff --git a/zebra/zebra_mpls.c b/zebra/zebra_mpls.c
index d1c9cd54af..6cee3aa39f 100644
--- a/zebra/zebra_mpls.c
+++ b/zebra/zebra_mpls.c
@@ -448,6 +448,14 @@ static int fec_send(struct zebra_fec *fec, struct zserv *client)
 }
 
 /*
+ * Upon reconfiguring nexthop-resolution updates, update the
+ * lsp entries accordingly.
+ */
+void zebra_mpls_fec_nexthop_resolution_update(struct zebra_vrf *zvrf)
+{
+}
+
+/*
  * Update all registered clients about this FEC. Caller should've updated
  * FEC and ensure no duplicate updates.
  */
diff --git a/zebra/zebra_mpls.h b/zebra/zebra_mpls.h
index dd6f960146..1f97c94347 100644
--- a/zebra/zebra_mpls.h
+++ b/zebra/zebra_mpls.h
@@ -257,6 +257,12 @@ void zebra_mpls_zapi_labels_process(bool add_p, struct zebra_vrf *zvrf,
 				    const struct zapi_labels *zl);
 
 /*
+ * Upon reconfiguring nexthop-resolution updates, update the
+ * lsp entries accordingly.
+ */
+void zebra_mpls_fec_nexthop_resolution_update(struct zebra_vrf *zvrf);
+
+/*
  * Uninstall all NHLFEs bound to a single FEC.
  *
  * mpls_ftn_uninstall -> Called to enqueue into early label processing
diff --git a/zebra/zebra_nb.c b/zebra/zebra_nb.c
index eee9323082..0a7ed5db41 100644
--- a/zebra/zebra_nb.c
+++ b/zebra/zebra_nb.c
@@ -884,6 +884,13 @@ const struct frr_yang_module_info frr_zebra_info = {
 			}
 		},
 		{
+			.xpath = "/frr-vrf:lib/vrf/frr-zebra:zebra/mpls/fec-nexthop-resolution",
+			.cbs = {
+				.modify = lib_vrf_zebra_mpls_fec_nexthop_resolution_modify,
+				.destroy = lib_vrf_zebra_mpls_fec_nexthop_resolution_destroy,
+			}
+		},
+		{
 			.xpath = "/frr-vrf:lib/vrf/frr-zebra:zebra/ribs/rib",
 			.cbs = {
 				.get_next = lib_vrf_zebra_ribs_rib_get_next,
diff --git a/zebra/zebra_nb.h b/zebra/zebra_nb.h
index b40ed68229..785291bc68 100644
--- a/zebra/zebra_nb.h
+++ b/zebra/zebra_nb.h
@@ -309,6 +309,10 @@ int lib_vrf_zebra_netns_table_range_create(struct nb_cb_create_args *args);
 int lib_vrf_zebra_netns_table_range_destroy(struct nb_cb_destroy_args *args);
 int lib_vrf_zebra_netns_table_range_start_modify(struct nb_cb_modify_args *args);
 int lib_vrf_zebra_netns_table_range_end_modify(struct nb_cb_modify_args *args);
+int lib_vrf_zebra_mpls_fec_nexthop_resolution_modify(
+	struct nb_cb_modify_args *args);
+int lib_vrf_zebra_mpls_fec_nexthop_resolution_destroy(
+	struct nb_cb_destroy_args *args);
 const void *lib_vrf_zebra_ribs_rib_get_next(struct nb_cb_get_next_args *args);
 int lib_vrf_zebra_ribs_rib_get_keys(struct nb_cb_get_keys_args *args);
 const void *
diff --git a/zebra/zebra_nb_config.c b/zebra/zebra_nb_config.c
index ae6232a1bb..09c0091ec6 100644
--- a/zebra/zebra_nb_config.c
+++ b/zebra/zebra_nb_config.c
@@ -3781,6 +3781,59 @@ int lib_vrf_zebra_netns_table_range_end_modify(struct nb_cb_modify_args *args)
 }
 
 /*
+ * XPath: /frr-vrf:lib/vrf/frr-zebra:zebra/mpls/fec-nexthop-resolution
+ */
+int lib_vrf_zebra_mpls_fec_nexthop_resolution_modify(
+	struct nb_cb_modify_args *args)
+{
+	struct vrf *vrf;
+	struct zebra_vrf *zvrf;
+	bool fec_nexthop_resolution;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	vrf = nb_running_get_entry(args->dnode, NULL, true);
+	zvrf = vrf->info;
+
+	fec_nexthop_resolution = yang_dnode_get_bool(args->dnode, NULL);
+
+	if (zvrf->zebra_mpls_fec_nexthop_resolution == fec_nexthop_resolution)
+		return NB_OK;
+
+	zvrf->zebra_mpls_fec_nexthop_resolution = fec_nexthop_resolution;
+
+	zebra_mpls_fec_nexthop_resolution_update(zvrf);
+
+	return NB_OK;
+}
+
+int lib_vrf_zebra_mpls_fec_nexthop_resolution_destroy(
+	struct nb_cb_destroy_args *args)
+{
+	struct vrf *vrf;
+	struct zebra_vrf *zvrf;
+	bool fec_nexthop_resolution;
+
+	if (args->event != NB_EV_APPLY)
+		return NB_OK;
+
+	vrf = nb_running_get_entry(args->dnode, NULL, true);
+	zvrf = vrf->info;
+
+	fec_nexthop_resolution = DFLT_ZEBRA_IP_NHT_RESOLVE_VIA_DEFAULT;
+
+	if (zvrf->zebra_mpls_fec_nexthop_resolution == fec_nexthop_resolution)
+		return NB_OK;
+
+	zvrf->zebra_mpls_fec_nexthop_resolution = fec_nexthop_resolution;
+
+	zebra_mpls_fec_nexthop_resolution_update(zvrf);
+
+	return NB_OK;
+}
+
+/*
  * XPath: /frr-vrf:lib/vrf/frr-zebra:zebra/l3vni-id
  */
 int lib_vrf_zebra_l3vni_id_modify(struct nb_cb_modify_args *args)
diff --git a/zebra/zebra_vrf.h b/zebra/zebra_vrf.h
index 5cbfab1ddc..f97138c811 100644
--- a/zebra/zebra_vrf.h
+++ b/zebra/zebra_vrf.h
@@ -173,6 +173,7 @@ struct zebra_vrf {
 
 	bool zebra_rnh_ip_default_route;
 	bool zebra_rnh_ipv6_default_route;
+	bool zebra_mpls_fec_nexthop_resolution;
 };
 #define PROTO_RM_NAME(zvrf, afi, rtype) zvrf->proto_rm[afi][rtype].name
 #define NHT_RM_NAME(zvrf, afi, rtype) zvrf->nht_rm[afi][rtype].name