ldpd, lib, zebra, topotests: add MPLS interface config from LDP

When LDP is enabled per interface, MPLS is not turned on on each of those interfaces. Fix this by letting LDP configure the interface if the 'mpls auto' mode is configured. Create an IMSG to send interface config request from ldpe thread to main thread of ldp. Create a ZAPI message to set MPLS from ldp to zebra. Update the MPLS setting. Add a test that ensures that LDP properly configures the interface. Signed-off-by: Philippe Guibert <[email protected]>
pguibert6WIND · May 17, 2024 · dbf2252 · dbf2252
1 parent 14711ad
commit dbf2252
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Showing 17 changed files with 162 additions and 3 deletions.
diff --git a/ldpd/interface.c b/ldpd/interface.c
@@ -8,6 +8,7 @@
  */
 
 #include <zebra.h>
+#include "privs.h"
 
 #include "ldpd.h"
 #include "ldpe.h"
@@ -16,6 +17,8 @@
 
 #include "sockopt.h"
 
+extern struct zebra_privs_t ldpe_privs;
+
 static __inline int	 iface_compare(const struct iface *, const struct iface *);
 static struct if_addr	*if_addr_new(struct kaddr *);
 static struct if_addr	*if_addr_lookup(struct if_addr_head *, struct kaddr *);
@@ -93,6 +96,20 @@ ldpe_if_init(struct iface *iface)
 	ldp_sync_fsm_init(iface, LDP_SYNC_STA_NOT_ACH);
 }
 
+/* proc sys net mpls conf <name> input set to 1 or 0
+ * should be used from ldpe only
+ */
+void ldpe_interface_set_mpls(struct iface *iface, bool val)
+{
+	struct ldp_igp_configure_if_mpls config;
+
+	config.ifindex = iface->ifindex;
+	config.enabled = val;
+
+	ldpe_imsg_compose_parent(IMSG_LDP_CONFIGURE_IF_MPLS, getpid(), &config,
+				 sizeof(config));
+}
+
 void
 ldpe_if_exit(struct iface *iface)
 {
@@ -277,6 +294,7 @@ if_start(struct iface *iface, int af)
 
 	log_debug("%s: %s address-family %s", __func__, iface->name, af_name(af));
 
+	ldpe_interface_set_mpls(iface, true);
 	ia = iface_af_get(iface, af);
 
 	gettimeofday(&now, NULL);

diff --git a/ldpd/ldp_zebra.c b/ldpd/ldp_zebra.c
@@ -124,6 +124,15 @@ ldp_sync_zebra_send_state_update(struct ldp_igp_sync_if_state *state)
 		return 0;
 }
 
+int ldp_sync_zebra_send_configure_if_mpls(struct ldp_igp_configure_if_mpls *config)
+{
+	if (zebra_send_interface_mpls_set(zclient, VRF_DEFAULT, config->ifindex,
+					  config->enabled) <= 0)
+		return -1;
+
+	return zclient_send_message(zclient);
+}
+
 static int
 ldp_sync_zebra_send_announce(void)
 {

diff --git a/ldpd/ldpd.c b/ldpd/ldpd.c
@@ -610,6 +610,15 @@ static void main_dispatch_ldpe(struct event *thread)
 
 			ldp_sync_zebra_send_state_update((struct ldp_igp_sync_if_state *)imsg.data);
 			break;
+		case IMSG_LDP_CONFIGURE_IF_MPLS:
+			if (imsg.hdr.len !=
+			    IMSG_HEADER_SIZE +
+				    sizeof(struct ldp_igp_configure_if_mpls))
+				fatalx("IMSG_LDP_CONFIGURE_IF_MPLS imsg with wrong len");
+
+			ldp_sync_zebra_send_configure_if_mpls(
+				(struct ldp_igp_configure_if_mpls *)imsg.data);
+			break;
 		default:
 			log_debug("%s: error handling imsg %d", __func__,
 			    imsg.hdr.type);
@@ -1524,6 +1533,7 @@ merge_ifaces(struct ldpd_conf *conf, struct ldpd_conf *xconf)
 		if (if_lookup_name(xconf, iface->name) == NULL) {
 			switch (ldpd_process) {
 			case PROC_LDP_ENGINE:
+				ldpe_interface_set_mpls(iface, false);
 				ldpe_if_exit(iface);
 				break;
 			case PROC_LDE_ENGINE:

diff --git a/ldpd/ldpd.h b/ldpd/ldpd.h
@@ -151,6 +151,7 @@ enum imsg_type {
 	IMSG_RLFA_UNREG_ALL,
 	IMSG_RLFA_LABELS,
 	IMSG_AGENTX_ENABLED,
+	IMSG_LDP_CONFIGURE_IF_MPLS,
 };
 
 struct ldpd_init {
@@ -890,6 +891,7 @@ extern char			 ctl_sock_path[MAXPATHLEN];
 void ldp_zebra_init(struct event_loop *m);
 void		 ldp_zebra_destroy(void);
 int		 ldp_sync_zebra_send_state_update(struct ldp_igp_sync_if_state *);
+int ldp_sync_zebra_send_configure_if_mpls(struct ldp_igp_configure_if_mpls *);
 int		 ldp_zebra_send_rlfa_labels(struct zapi_rlfa_response *
 		    rlfa_labels);
 

diff --git a/ldpd/ldpe.h b/ldpd/ldpe.h
@@ -306,6 +306,7 @@ void	ldpe_l2vpn_init(struct l2vpn *);
 void	ldpe_l2vpn_exit(struct l2vpn *);
 void	ldpe_l2vpn_pw_init(struct l2vpn_pw *);
 void	ldpe_l2vpn_pw_exit(struct l2vpn_pw *);
+extern void ldpe_interface_set_mpls(struct iface *iface, bool val);
 
 DECLARE_HOOK(ldp_nbr_state_change, (struct nbr * nbr, int old_state),
 	     (nbr, old_state));

diff --git a/lib/ldp_sync.h b/lib/ldp_sync.h
@@ -56,6 +56,11 @@ struct ldp_igp_sync_if_state {
 	bool sync_start;
 };
 
+struct ldp_igp_configure_if_mpls {
+	ifindex_t ifindex;
+	bool enabled;
+};
+
 struct ldp_igp_sync_if_state_req {
 	int proto;
 	ifindex_t ifindex;

diff --git a/lib/zclient.c b/lib/zclient.c
@@ -2867,6 +2867,51 @@ size_t zebra_interface_link_params_write(struct stream *s,
 	return w;
 }
 
+int zebra_send_interface_mpls_set(struct zclient *zclient, vrf_id_t vrf_id,
+				  ifindex_t ifindex, bool set)
+{
+	struct stream *s;
+
+	if (!zclient->obuf)
+		return 0;
+
+	s = zclient->obuf;
+	stream_reset(s);
+
+	zclient_create_header(s, ZEBRA_INTERFACE_MPLS_SET, VRF_DEFAULT);
+
+	stream_putl(s, ifindex);
+	stream_putc(s, set);
+
+	stream_putw_at(s, 0, stream_get_endp(s));
+
+	return zclient_send_message(zclient);
+}
+
+struct interface *zebra_interface_mpls_set_read(struct stream *s,
+						vrf_id_t vrf_id,
+						bool *value_to_set)
+{
+	ifindex_t ifindex;
+	struct interface *ifp = NULL;
+
+	STREAM_GETL(s, ifindex);
+
+	ifp = if_lookup_by_index(ifindex, vrf_id);
+
+	if (ifp == NULL) {
+		flog_err(EC_LIB_ZAPI_ENCODE,
+			 "%s: unknown ifindex %u, shouldn't happen", __func__,
+			 ifindex);
+		return NULL;
+	}
+	if (value_to_set)
+		STREAM_GETC(s, *value_to_set);
+
+stream_failure:
+	return ifp;
+}
+
 /*
  * format of message for address addition is:
  *    0

diff --git a/lib/zclient.h b/lib/zclient.h
@@ -134,6 +134,7 @@ typedef enum {
 	ZEBRA_INTERFACE_DISABLE_RADV,
 	ZEBRA_NEXTHOP_LOOKUP_MRIB,
 	ZEBRA_INTERFACE_LINK_PARAMS,
+	ZEBRA_INTERFACE_MPLS_SET,
 	ZEBRA_MPLS_LABELS_ADD,
 	ZEBRA_MPLS_LABELS_DELETE,
 	ZEBRA_MPLS_LABELS_REPLACE,
@@ -1055,6 +1056,12 @@ extern struct interface *zebra_interface_link_params_read(struct stream *s,
 							  bool *changed);
 extern size_t zebra_interface_link_params_write(struct stream *,
 						struct interface *);
+extern int zebra_send_interface_mpls_set(struct zclient *zclient,
+					 vrf_id_t vrf_id, ifindex_t ifindex,
+					 bool set);
+extern struct interface *zebra_interface_mpls_set_read(struct stream *s,
+						       vrf_id_t vrf_id,
+						       bool *value_to_set);
 extern enum zclient_send_status
 zclient_send_get_label_chunk(struct zclient *zclient, uint8_t keep,
 			     uint32_t chunk_size, uint32_t base);

diff --git a/tests/topotests/ldp_topo1/r1/zebra.conf b/tests/topotests/ldp_topo1/r1/zebra.conf
@@ -9,6 +9,7 @@ interface r1-eth0
  description to sw0
  ip address 10.0.1.1/24
  no link-detect
+ mpls auto
 !
 ip forwarding
 !

diff --git a/tests/topotests/ldp_topo1/r2/zebra.conf b/tests/topotests/ldp_topo1/r2/zebra.conf
@@ -9,16 +9,19 @@ interface r2-eth0
  description to sw0
  ip address 10.0.1.2/24
  no link-detect
+ mpls auto
 !
 interface r2-eth1
  description to sw1
  ip address 10.0.2.2/24
  no link-detect
+ mpls auto
 !
 interface r2-eth2
  description to sw2
  ip address 10.0.3.2/24
  no link-detect
+ mpls auto
 !
 ip forwarding
 !

diff --git a/tests/topotests/ldp_topo1/r3/zebra.conf b/tests/topotests/ldp_topo1/r3/zebra.conf
@@ -9,11 +9,13 @@ interface r3-eth0
  description to sw1
  ip address 10.0.2.3/24
  no link-detect
+ mpls auto
 !
 interface r3-eth1
  description to sw2
  ip address 10.0.3.3/24
  no link-detect
+ mpls auto
 !
 ip forwarding
 !

diff --git a/tests/topotests/ldp_topo1/r4/zebra.conf b/tests/topotests/ldp_topo1/r4/zebra.conf
@@ -9,6 +9,7 @@ interface r4-eth0
  description to sw1
  ip address 10.0.2.4/24
  no link-detect
+ mpls auto
 !
 ip forwarding
 !

diff --git a/tests/topotests/ldp_topo1/test_ldp_topo1.py b/tests/topotests/ldp_topo1/test_ldp_topo1.py
@@ -75,7 +75,6 @@
 
 
 def build_topo(tgen):
-
     # Setup Routers
     for i in range(1, 5):
         tgen.add_router("r%s" % i)
@@ -134,6 +133,7 @@ def setup_module(module):
     tgen.start_topology()
 
     net = tgen.net
+    os.environ["TOPOTESTS_MPLS_AUTO"] = "1"
 
     # Starting Routers
     for i in range(1, 5):
@@ -781,6 +781,37 @@ def test_linux_mpls_routes():
         assert fatal_error == "", fatal_error
 
 
+def _check_mpls_interface_set(rname, ifname, value):
+    tgen = get_topogen()
+    val = (
+        tgen.net[rname]
+        .cmd_raises("sysctl -n " + "net.mpls.conf." + ifname + ".input")
+        .strip()
+    )
+    assert (
+        val == value
+    ), f"{rname}, interface {ifname} has MPLS flag set to {val}, unexpected"
+
+
+def test_linux_mpls_interface_settings():
+    global fatal_error
+
+    # Skip if previous fatal error condition is raised
+    if fatal_error != "":
+        pytest.skip(fatal_error)
+
+    # Verify Linux Kernel MPLS settings
+    print("\n\n** Verifying Linux MPLS interface settings")
+    print("******************************************\n")
+    _check_mpls_interface_set("r1", "r1-eth0", "1")
+    _check_mpls_interface_set("r2", "r2-eth0", "1")
+    _check_mpls_interface_set("r2", "r2-eth1", "1")
+    _check_mpls_interface_set("r2", "r2-eth2", "1")
+    _check_mpls_interface_set("r3", "r3-eth0", "1")
+    _check_mpls_interface_set("r3", "r3-eth1", "1")
+    _check_mpls_interface_set("r4", "r4-eth0", "1")
+
+
 def test_shutdown_check_stderr():
     global fatal_error
     net = get_topogen().net
@@ -837,7 +868,6 @@ def test_shutdown_check_memleak():
 
 
 if __name__ == "__main__":
-
     # To suppress tracebacks, either use the following pytest call or add "--tb=no" to cli
     # retval = pytest.main(["-s", "--tb=no"])
     retval = pytest.main(["-s"])

diff --git a/tests/topotests/lib/topogen.py b/tests/topotests/lib/topogen.py
@@ -907,9 +907,13 @@ def start(self):
                     daemon=daemon,
                 )
 
+        if nrouter.daemons["ldpd"] == 1 and not os.environ.get("TOPOTESTS_MPLS_AUTO"):
+            need_mpls_for_ldp = True
+        else:
+            need_mpls_for_ldp = False
         if result != "":
             self.tgen.set_error(result)
-        elif nrouter.daemons["ldpd"] == 1 or nrouter.daemons["pathd"] == 1:
+        elif need_mpls_for_ldp or nrouter.daemons["pathd"] == 1:
             # Enable MPLS processing on all interfaces.
             for interface in self.links:
                 topotest.sysctl_assure(

diff --git a/zebra/interface.c b/zebra/interface.c
@@ -3974,6 +3974,23 @@ void mpls_auto_interface_data_off(struct interface *ifp)
 	mpls_auto_interface_data_internal(ifp, false);
 }
 
+void zebra_interface_mpls_set(ZAPI_HANDLER_ARGS)
+{
+	struct interface *ifp;
+	bool mpls = false;
+	struct stream *s;
+
+	s = msg;
+	ifp = zebra_interface_mpls_set_read(s, zvrf->vrf->vrf_id, &mpls);
+	if (!ifp)
+		return;
+
+	if (mpls)
+		mpls_auto_interface_data_on(ifp);
+	else
+		mpls_auto_interface_data_off(ifp);
+}
+
 /* Allocate and initialize interface vector. */
 void zebra_if_init(void)
 {

diff --git a/zebra/interface.h b/zebra/interface.h
@@ -17,6 +17,7 @@
 #include "zebra/zebra_nhg_private.h"
 #include "zebra/zebra_router.h"
 #include "zebra/rtadv.h"
+#include "zebra/zserv.h"
 
 #ifdef __cplusplus
 extern "C" {
@@ -354,6 +355,8 @@ extern const char *zebra_protodown_rc_str(uint32_t protodown_rc, char *pd_buf,
 					  uint32_t pd_buf_len);
 extern void mpls_auto_interface_data_off(struct interface *ifp);
 extern void mpls_auto_interface_data_on(struct interface *ifp);
+extern void zebra_interface_mpls_set(struct zserv *client, struct zmsghdr *hdr,
+				     struct stream *msg, struct zebra_vrf *zvrf);
 void zebra_if_dplane_result(struct zebra_dplane_ctx *ctx);
 
 #ifdef HAVE_PROC_NET_DEV

diff --git a/zebra/zapi_msg.c b/zebra/zapi_msg.c
@@ -3908,6 +3908,7 @@ void (*const zserv_handlers[])(ZAPI_HANDLER_ARGS) = {
 	[ZEBRA_BFD_CLIENT_REGISTER] = zebra_ptm_bfd_client_register,
 	[ZEBRA_INTERFACE_ENABLE_RADV] = zebra_interface_radv_enable,
 	[ZEBRA_INTERFACE_DISABLE_RADV] = zebra_interface_radv_disable,
+	[ZEBRA_INTERFACE_MPLS_SET] = zebra_interface_mpls_set,
 	[ZEBRA_SR_POLICY_SET] = zread_sr_policy_set,
 	[ZEBRA_SR_POLICY_DELETE] = zread_sr_policy_delete,
 	[ZEBRA_MPLS_LABELS_ADD] = zread_mpls_labels_add,