Merge pull request #7 from vifino/mpls

Basic MPLS support!

See the following references:
https://ipng.ch/s/articles/2023/05/07/vpp-mpls-1.html
https://ipng.ch/s/articles/2023/05/17/vpp-mpls-2.html
https://ipng.ch/s/articles/2023/05/21/vpp-mpls-3.html
https://ipng.ch/s/articles/2023/05/28/vpp-mpls-4.html

And contact vpp-dev@lists.fd.io for support.

CMakeLists.txt

@@ -29,6 +29,7 @@ add_vpp_library(lcpng
   lcpng_interface.c
   lcpng_adj.c
   lcpng_if_sync.c
+  lcpng_mpls_sync.c
   lcpng.c
 
   LINK_LIBRARIES

lcpng.c

@@ -23,7 +23,9 @@
 
 lcp_main_t lcp_main;
 
-u8 *lcp_get_default_ns(void) {
+u8 *
+lcp_get_default_ns (void)
+{
   lcp_main_t *lcpm = &lcp_main;
 
   if (!lcpm->default_namespace || lcpm->default_namespace[0] == 0)
@@ -31,7 +33,9 @@ u8 *lcp_get_default_ns(void) {
   return lcpm->default_namespace;
 }
 
-int lcp_get_default_ns_fd(void) {
+int
+lcp_get_default_ns_fd (void)
+{
   lcp_main_t *lcpm = &lcp_main;
 
   return lcpm->default_ns_fd;
@@ -40,7 +44,9 @@ int lcp_get_default_ns_fd(void) {
 /*
  * ns is expected to be or look like a NUL-terminated C string.
  */
-int lcp_set_default_ns(u8 *ns) {
+int
+lcp_set_default_ns (u8 *ns)
+{
   lcp_main_t *lcpm = &lcp_main;
   char *p;
   int len;

lcpng_if.api

@@ -134,9 +134,10 @@ autoendian define lcp_itf_pair_details
   string netns[32]; /* LCP_NS_LEN */
 };
 
-service {
+service
-  rpc lcp_itf_pair_get returns lcp_itf_pair_get_reply
+{
-    stream lcp_itf_pair_details;
+  rpc lcp_itf_pair_get returns lcp_itf_pair_get_reply stream
+    lcp_itf_pair_details;
 };
 
 /** \brief Replace end/begin
@@ -155,14 +156,17 @@ autoreply define lcp_itf_pair_replace_end
 /*
  * Linux-CP Error counters/messages
  */
-counters linuxcp {
+counters linuxcp
-  packets {
+{
+  packets
+  {
     severity info;
     type counter64;
     units "packets";
     description "ARP packets processed";
   };
-  copies {
+  copies
+  {
     severity info;
     type counter64;
     units "packets";
@@ -170,9 +174,12 @@ counters linuxcp {
   };
 };
 
-paths {
+paths
-  "/err/linux-cp-arp-phy" "linuxcp";
+{
-  "/err/linux-cp-arp-host" "linuxcp";
+  "/err/linux-cp-arp-phy"
+  "linuxcp";
+  "/err/linux-cp-arp-host"
+  "linuxcp";
 };
 
 /*

lcpng_if_api.c

@@ -162,7 +162,8 @@ vl_api_lcp_itf_pair_get_t_handler (vl_api_lcp_itf_pair_get_t *mp)
 }
 
 static void
-vl_api_lcp_default_ns_set_t_handler(vl_api_lcp_default_ns_set_t *mp) {
+vl_api_lcp_default_ns_set_t_handler (vl_api_lcp_default_ns_set_t *mp)
+{
   vl_api_lcp_default_ns_set_reply_t *rmp;
   int rv;
 
@@ -173,7 +174,8 @@ vl_api_lcp_default_ns_set_t_handler(vl_api_lcp_default_ns_set_t *mp) {
 }
 
 static void
-vl_api_lcp_default_ns_get_t_handler(vl_api_lcp_default_ns_get_t *mp) {
+vl_api_lcp_default_ns_get_t_handler (vl_api_lcp_default_ns_get_t *mp)
+{
   vl_api_lcp_default_ns_get_reply_t *rmp;
   vl_api_registration_t *reg;
   char *ns;

lcpng_if_cli.c

@@ -173,9 +173,10 @@ VLIB_CLI_COMMAND (lcp_auto_subint_command, static) = {
   .function = lcp_auto_subint_command_fn,
 };
 
-static clib_error_t *lcp_default_netns_command_fn(vlib_main_t *vm,
+static clib_error_t *
-                                                  unformat_input_t *input,
+lcp_default_netns_command_fn (vlib_main_t *vm, unformat_input_t *input,
-                                                  vlib_cli_command_t *cmd) {
+			      vlib_cli_command_t *cmd)
+{
   unformat_input_t _line_input, *line_input = &_line_input;
   u8 *ns;
   int r;
@@ -186,7 +187,8 @@ static clib_error_t *lcp_default_netns_command_fn(vlib_main_t *vm,
 
   ns = 0;
 
-  while (unformat_check_input(line_input) != UNFORMAT_END_OF_INPUT) {
+  while (unformat_check_input (line_input) != UNFORMAT_END_OF_INPUT)
+    {
       if (unformat (line_input, "netns %s", &ns))
 	;
       else if (unformat (line_input, "clear netns"))

lcpng_if_node.c

@@ -438,6 +438,103 @@ VNET_FEATURE_INIT(lcp_xc_ip6_mcast_node, static) = {
   .node_name = "linux-cp-xc-ip6",
 };
 
+typedef enum
+{
+  LCP_XC_MPLS_NEXT_DROP,
+  LCP_XC_MPLS_NEXT_IO,
+  LCP_XC_MPLS_N_NEXT,
+} lcp_xc_mpls_next_t;
+
+static_always_inline uword
+lcp_xc_mpls_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
+		    vlib_frame_t *frame)
+{
+  u32 n_left_from, *from, *to_next, n_left_to_next;
+  lcp_xc_next_t next_index;
+
+  next_index = 0;
+  n_left_from = frame->n_vectors;
+  from = vlib_frame_vector_args (frame);
+
+  while (n_left_from > 0)
+    {
+      vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
+
+      while (n_left_from > 0 && n_left_to_next > 0)
+	{
+	  const ethernet_header_t *eth;
+	  const lcp_itf_pair_t *lip;
+	  u32 next0, bi0, lipi, ai;
+	  vlib_buffer_t *b0;
+	  // const ip_adjacency_t *adj;
+
+	  bi0 = to_next[0] = from[0];
+
+	  from += 1;
+	  to_next += 1;
+	  n_left_from -= 1;
+	  n_left_to_next -= 1;
+
+	  b0 = vlib_get_buffer (vm, bi0);
+
+	  lipi =
+	    lcp_itf_pair_find_by_host (vnet_buffer (b0)->sw_if_index[VLIB_RX]);
+	  lip = lcp_itf_pair_get (lipi);
+
+	  vnet_buffer (b0)->sw_if_index[VLIB_TX] = lip->lip_phy_sw_if_index;
+	  vlib_buffer_advance (b0, -lip->lip_rewrite_len);
+	  eth = vlib_buffer_get_current (b0);
+
+	  ai = ADJ_INDEX_INVALID;
+	  next0 = LCP_XC_MPLS_NEXT_DROP;
+	  if (!ethernet_address_cast (eth->dst_address))
+	    ai = lcp_adj_lkup ((u8 *) eth, lip->lip_rewrite_len,
+			       vnet_buffer (b0)->sw_if_index[VLIB_TX]);
+	  if (ai != ADJ_INDEX_INVALID)
+	    {
+	      vnet_buffer (b0)->ip.adj_index[VLIB_TX] = ai;
+	      next0 = LCP_XC_MPLS_NEXT_IO;
+	    }
+
+	  if (PREDICT_FALSE ((b0->flags & VLIB_BUFFER_IS_TRACED)))
+	    {
+	      lcp_xc_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t));
+	      t->phy_sw_if_index = lip->lip_phy_sw_if_index;
+	      t->adj_index = vnet_buffer (b0)->ip.adj_index[VLIB_TX];
+	    }
+
+	  vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
+					   n_left_to_next, bi0, next0);
+	}
+
+      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+    }
+
+  return frame->n_vectors;
+}
+
+VLIB_NODE_FN (lcp_xc_mpls)
+(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
+{
+  return (lcp_xc_mpls_inline (vm, node, frame));
+}
+
+VLIB_REGISTER_NODE (
+  lcp_xc_mpls) = { .name = "linux-cp-xc-mpls",
+		   .vector_size = sizeof (u32),
+		   .format_trace = format_lcp_xc_trace,
+		   .type = VLIB_NODE_TYPE_INTERNAL,
+		   .n_next_nodes = LCP_XC_MPLS_N_NEXT,
+		   .next_nodes = {
+		     [LCP_XC_MPLS_NEXT_DROP] = "error-drop",
+		     [LCP_XC_MPLS_NEXT_IO] = "interface-output",
+		   } };
+
+VNET_FEATURE_INIT (lcp_xc_mpls_node, static) = {
+  .arc_name = "mpls-input",
+  .node_name = "linux-cp-xc-mpls",
+};
+
 typedef enum
 {
   LCP_XC_L3_NEXT_XC,

lcpng_if_sync.c

@@ -184,7 +184,8 @@ lcp_itf_admin_state_change (vnet_main_t * vnm, u32 sw_if_index, u32 flags)
 
   // Sync interface state changes into host
   lip = lcp_itf_pair_get (lcp_itf_pair_find_by_phy (sw_if_index));
-  if (!lip) return NULL;
+  if (!lip)
+    return NULL;
   LCP_IF_INFO ("admin_state_change: %U flags %u", format_lcp_itf_pair, lip,
 	       flags);
 

lcpng_interface.c

@@ -149,8 +149,10 @@ lcp_itf_pair_show (u32 phy_sw_if_index)
 lcp_itf_pair_t *
 lcp_itf_pair_get (u32 index)
 {
-  if (!lcp_itf_pair_pool) return NULL;
+  if (!lcp_itf_pair_pool)
-  if (index == INDEX_INVALID) return NULL;
+    return NULL;
+  if (index == INDEX_INVALID)
+    return NULL;
 
   return pool_elt_at_index (lcp_itf_pair_pool, index);
 }
@@ -230,12 +232,14 @@ lcp_itf_pair_add (u32 host_sw_if_index, u32 phy_sw_if_index, u8 *host_name,
   if (lipi != INDEX_INVALID)
     return VNET_API_ERROR_VALUE_EXIST;
 
-  if (host_sw_if_index == ~0) {
+  if (host_sw_if_index == ~0)
+    {
       LCP_IF_ERROR ("pair_add: Cannot add LIP - invalid host");
       return VNET_API_ERROR_INVALID_SW_IF_INDEX;
     }
 
-  if (phy_sw_if_index == ~0) {
+  if (phy_sw_if_index == ~0)
+    {
       LCP_IF_ERROR ("pair_add: Cannot add LIP - invalid phy");
       return VNET_API_ERROR_INVALID_SW_IF_INDEX;
     }
@@ -278,6 +282,10 @@ lcp_itf_pair_add (u32 host_sw_if_index, u32 phy_sw_if_index, u8 *host_name,
 			     lcp_itf_l3_feat_names[lip->lip_host_type][af],
 			     lip->lip_host_sw_if_index, 1, NULL, 0);
 
+  /* Enable MPLS */
+  vnet_feature_enable_disable ("mpls-input", "linux-cp-xc-mpls",
+			       lip->lip_host_sw_if_index, 1, NULL, 0);
+
   /*
    * Configure passive punt to the host interface.
    */
@@ -343,7 +351,8 @@ lcp_netlink_add_link_vlan (int parent, u32 vlan, u16 proto, const char *name)
   int err;
 
   sk = nl_socket_alloc ();
-  if ((err = nl_connect (sk, NETLINK_ROUTE)) < 0) {
+  if ((err = nl_connect (sk, NETLINK_ROUTE)) < 0)
+    {
       LCP_IF_ERROR ("netlink_add_link_vlan: Netlink connect error: %s",
 		    nl_geterror (err));
       return clib_error_return (NULL, "Unable to connect socket: %d", err);
@@ -356,7 +365,8 @@ lcp_netlink_add_link_vlan (int parent, u32 vlan, u16 proto, const char *name)
   rtnl_link_vlan_set_id (link, vlan);
   rtnl_link_vlan_set_protocol (link, htons (proto));
 
-  if ((err = rtnl_link_add (sk, link, NLM_F_CREATE)) < 0) {
+  if ((err = rtnl_link_add (sk, link, NLM_F_CREATE)) < 0)
+    {
       LCP_IF_ERROR ("netlink_add_link_vlan: Netlink link add error: %s",
 		    nl_geterror (err));
       return clib_error_return (NULL, "Unable to add link %s: %d", name, err);
@@ -424,6 +434,9 @@ lcp_itf_pair_del (u32 phy_sw_if_index)
 			     lcp_itf_l3_feat_names[lip->lip_host_type][af],
 			     lip->lip_host_sw_if_index, 0, NULL, 0);
 
+  vnet_feature_enable_disable ("mpls-input", "linux-cp-xc-mpls",
+			       lip->lip_host_sw_if_index, 0, NULL, 0);
+
   lcp_itf_unset_adjs (lip);
 
   ip4_punt_redirect_del (lip->lip_phy_sw_if_index);
@@ -611,7 +624,8 @@ lcp_itf_set_link_state (const lcp_itf_pair_t *lip, u8 state)
   vnet_main_t *vnm = vnet_get_main ();
   int curr_ns_fd, vif_ns_fd;
 
-  if (!lip) return;
+  if (!lip)
+    return;
 
   curr_ns_fd = vif_ns_fd = -1;
 
@@ -769,12 +783,14 @@ lcp_itf_pair_create (u32 phy_sw_if_index, u8 *host_if_name,
   const vnet_hw_interface_t *hw;
   lcp_itf_pair_t *lip;
 
-  if (!vnet_sw_if_index_is_api_valid (phy_sw_if_index)) {
+  if (!vnet_sw_if_index_is_api_valid (phy_sw_if_index))
+    {
       LCP_IF_ERROR ("pair_create: Invalid phy index %u", phy_sw_if_index);
       return VNET_API_ERROR_INVALID_SW_IF_INDEX;
     }
 
-  if (!lcp_validate_if_name (host_if_name)) {
+  if (!lcp_validate_if_name (host_if_name))
+    {
       LCP_IF_ERROR ("pair_create: Invalid host-if-name '%s'", host_if_name);
       return VNET_API_ERROR_INVALID_ARGUMENT;
     }
@@ -782,13 +798,15 @@ lcp_itf_pair_create (u32 phy_sw_if_index, u8 *host_if_name,
   vnm = vnet_get_main ();
   sw = vnet_get_sw_interface (vnm, phy_sw_if_index);
   hw = vnet_get_sup_hw_interface (vnm, phy_sw_if_index);
-  if (!sw && !hw) {
+  if (!sw && !hw)
+    {
       LCP_IF_ERROR ("pair_create: Invalid interface");
       return VNET_API_ERROR_INVALID_SW_IF_INDEX;
     }
 
   if (hw->hw_class_index != ethernet_hw_interface_class.index &&
-      host_if_type == LCP_ITF_HOST_TAP) {
+      host_if_type == LCP_ITF_HOST_TAP)
+    {
       LCP_IF_ERROR (
 	"pair_create: don't create TAP for non-eth interface; use tun");
       return VNET_API_ERROR_INVALID_ARGUMENT;
@@ -812,7 +830,9 @@ lcp_itf_pair_create (u32 phy_sw_if_index, u8 *host_if_name,
       u16 vlan, proto;
       u32 parent_vif_index;
 
-      if (sw->type == VNET_SW_INTERFACE_TYPE_SUB && sw->sub.eth.flags.exact_match == 0) {
+      if (sw->type == VNET_SW_INTERFACE_TYPE_SUB &&
+	  sw->sub.eth.flags.exact_match == 0)
+	{
 	  LCP_IF_ERROR ("pair_create: Cannot create LIP for a "
 			"sub-interface without exact-match set");
 	  return VNET_API_ERROR_INVALID_ARGUMENT;
@@ -821,7 +841,8 @@ lcp_itf_pair_create (u32 phy_sw_if_index, u8 *host_if_name,
       outer_vlan = sw->sub.eth.outer_vlan_id;
       inner_vlan = sw->sub.eth.inner_vlan_id;
       outer_proto = inner_proto = ETH_P_8021Q;
-      if (1 == sw->sub.eth.flags.dot1ad) outer_proto = ETH_P_8021AD;
+      if (1 == sw->sub.eth.flags.dot1ad)
+	outer_proto = ETH_P_8021AD;
 
       LCP_IF_INFO ("pair_create: creating dot1%s %d inner-dot1q %d on %U",
 		   sw->sub.eth.flags.dot1ad ? "ad" : "q", outer_vlan,
@@ -916,7 +937,8 @@ lcp_itf_pair_create (u32 phy_sw_if_index, u8 *host_if_name,
 
 	  err = lcp_netlink_add_link_vlan (parent_vif_index, vlan, proto,
 					   (const char *) host_if_name);
-	  if (err != 0) {
+	  if (err != 0)
+	    {
 	      LCP_IF_ERROR ("pair_create: Cannot create link "
 			    "outer(proto:0x%04x,vlan:%u).inner(proto:0x%"
 			    "04x,vlan:%u) name:'%s'",

lcpng_mpls_sync.c

@@ -0,0 +1,140 @@
+/*
+ * Copyright (c) 2023 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define _GNU_SOURCE
+
+#include <vnet/plugin/plugin.h>
+#include <vnet/mpls/mpls.h>
+#include <vppinfra/linux/netns.h>
+
+#include <fcntl.h>
+
+#include <plugins/lcpng/lcpng_interface.h>
+
+void
+lcp_mpls_sync_pair_add_cb (lcp_itf_pair_t *lip)
+{
+  u8 phy_is_enabled = mpls_sw_interface_is_enabled (lip->lip_phy_sw_if_index);
+  LCP_IF_DBG ("mpls_pair_add_cb: mpls enabled %u, parent %U", phy_is_enabled,
+	      format_lcp_itf_pair, lip);
+  if (phy_is_enabled)
+    mpls_sw_interface_enable_disable (&mpls_main, lip->lip_host_sw_if_index,
+				      1);
+}
+
+void
+lcp_mpls_sync_state_cb (struct mpls_main_t *mm, uword opaque, u32 sw_if_index,
+			u32 is_enable)
+{
+  lcp_itf_pair_t *lip;
+  index_t lipi;
+  int curr_ns_fd = -1;
+  int vif_ns_fd = -1;
+  int ctl_fd = -1;
+  u8 *ctl_path = NULL;
+
+  LCP_IF_DBG ("mpls_sync_state_cb: called for sw_if_index %u", sw_if_index);
+
+  // If device is LCP PHY, sync state to host tap.
+  lipi = lcp_itf_pair_find_by_phy (sw_if_index);
+  if (INDEX_INVALID != lipi)
+    {
+      lip = lcp_itf_pair_get (lipi);
+      LCP_IF_DBG ("mpls_sync_state_cb: mpls enabled %u parent %U", is_enable,
+		  format_lcp_itf_pair, lip);
+      mpls_sw_interface_enable_disable (&mpls_main, lip->lip_host_sw_if_index,
+					is_enable);
+      return;
+    }
+
+  // If device is LCP host, sync state to linux.
+  lipi = lcp_itf_pair_find_by_host (sw_if_index);
+  if (INDEX_INVALID == lipi)
+    return;
+
+  lip = lcp_itf_pair_get (lipi);
+  if (lip->lip_namespace)
+    {
+      curr_ns_fd = clib_netns_open (NULL /* self */);
+      vif_ns_fd = clib_netns_open (lip->lip_namespace);
+      if (vif_ns_fd != -1)
+	clib_setns (vif_ns_fd);
+    }
+
+  ctl_path = format (NULL, "/proc/sys/net/mpls/conf/%s/input%c",
+		     lip->lip_host_name, NULL);
+  if (NULL == ctl_path)
+    {
+      LCP_IF_DBG ("mpls_sync_state_cb: failed to format sysctl");
+      goto SYNC_CLEANUP;
+    }
+
+  ctl_fd = open ((char *) ctl_path, O_WRONLY);
+  if (ctl_fd < 0)
+    {
+      LCP_IF_DBG ("mpls_sync_state_cb: failed to open %s for writing",
+		  ctl_path);
+      goto SYNC_CLEANUP;
+    }
+
+  if (fdformat (ctl_fd, "%u", is_enable) < 1)
+    {
+      LCP_IF_DBG ("mpls_sync_state_cb: failed to write to %s", ctl_path);
+      goto SYNC_CLEANUP;
+    }
+
+  LCP_IF_DBG ("mpls_sync_state_cb: set mpls input for %s", lip->lip_host_name);
+
+SYNC_CLEANUP:
+  if (ctl_fd < 0)
+    close (ctl_fd);
+
+  if (NULL != ctl_path)
+    vec_free (ctl_path);
+
+  if (vif_ns_fd != -1)
+    close (vif_ns_fd);
+
+  if (curr_ns_fd != -1)
+    {
+      clib_setns (curr_ns_fd);
+      close (curr_ns_fd);
+    }
+}
+
+static clib_error_t *
+lcp_mpls_sync_init (vlib_main_t *vm)
+{
+  lcp_itf_pair_vft_t mpls_sync_itf_pair_vft = {
+    .pair_add_fn = lcp_mpls_sync_pair_add_cb,
+  };
+  lcp_itf_pair_register_vft (&mpls_sync_itf_pair_vft);
+
+  mpls_interface_state_change_add_callback (lcp_mpls_sync_state_cb, 0);
+
+  return NULL;
+}
+
+VLIB_INIT_FUNCTION (lcp_mpls_sync_init) = {
+  .runs_after = VLIB_INITS ("lcp_itf_pair_init", "mpls_init"),
+};
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */

lcpng_netlink.h

@@ -22,6 +22,7 @@
 #include <netlink/route/link.h>
 #include <netlink/route/route.h>
 #include <netlink/route/neighbour.h>
+#include <netlink/route/nexthop.h>
 #include <netlink/route/addr.h>
 #include <netlink/route/link/vlan.h>
 

lcpng_nl_sync.c

@@ -17,6 +17,7 @@
 
 #include <sys/socket.h>
 #include <linux/if.h>
+#include <linux/mpls.h>
 
 #include <vnet/vnet.h>
 #include <vnet/plugin/plugin.h>
@@ -146,13 +147,31 @@ vnet_sw_interface_get_available_subid (vnet_main_t *vnm, u32 sw_if_index,
   return 1;
 }
 
+static fib_protocol_t
+lcp_nl_proto_k2f (uint32_t k)
+{
+  switch (k)
+    {
+    case AF_INET6:
+      return FIB_PROTOCOL_IP6;
+    case AF_INET:
+      return FIB_PROTOCOL_IP4;
+    case AF_MPLS:
+      return FIB_PROTOCOL_MPLS;
+    default:
+      ASSERT (0);
+      return FIB_PROTOCOL_NONE;
+    }
+}
+
 static fib_protocol_t
 lcp_nl_mk_addr46 (const struct nl_addr *rna, ip46_address_t *ia)
 {
   fib_protocol_t fproto;
 
-  fproto =
+  fproto = lcp_nl_proto_k2f (nl_addr_get_family (rna));
-    nl_addr_get_family (rna) == AF_INET6 ? FIB_PROTOCOL_IP6 : FIB_PROTOCOL_IP4;
+  ASSERT (FIB_PROTOCOL_MPLS != fproto);
+
   ip46_address_reset (ia);
   if (FIB_PROTOCOL_IP4 == fproto)
     memcpy (&ia->ip4, nl_addr_get_binary_addr (rna), nl_addr_get_len (rna));
@@ -166,9 +185,31 @@ static void
 lcp_nl_mk_route_prefix (struct rtnl_route *r, fib_prefix_t *p)
 {
   const struct nl_addr *addr = rtnl_route_get_dst (r);
+  u32 *baddr = nl_addr_get_binary_addr (addr);
+  u32 blen = nl_addr_get_len (addr);
+  ip46_address_t *paddr = &p->fp_addr;
+  u32 entry;
+
+  p->fp_proto = lcp_nl_proto_k2f (nl_addr_get_family (addr));
+
+  switch (p->fp_proto)
+    {
+    case FIB_PROTOCOL_MPLS:
+      entry = ntohl (*baddr);
+      p->fp_label = (entry & MPLS_LS_LABEL_MASK) >> MPLS_LS_LABEL_SHIFT;
+      p->fp_len = 21;
+      p->fp_eos = MPLS_NON_EOS;
+      return;
+    case FIB_PROTOCOL_IP4:
+      ip46_address_reset (paddr);
+      memcpy (&paddr->ip4, baddr, blen);
+      break;
+    case FIB_PROTOCOL_IP6:
+      memcpy (&paddr->ip6, baddr, blen);
+      break;
+    }
 
   p->fp_len = nl_addr_get_prefixlen (addr);
-  p->fp_proto = lcp_nl_mk_addr46 (addr, &p->fp_addr);
 }
 
 static void
@@ -208,6 +249,37 @@ lcp_nl_mk_route_entry_flags (uint8_t rtype, int table_id, uint8_t rproto)
   return (fef);
 }
 
+static int
+lcp_router_mpls_nladdr_to_path (fib_route_path_t *path, struct nl_addr *addr)
+{
+  if (!addr)
+    return 0;
+
+  struct mpls_label *stack = nl_addr_get_binary_addr (addr);
+  u32 entry, label;
+  u8 exp, ttl;
+  int label_count = 0;
+
+  while (1)
+    {
+      entry = ntohl (stack[label_count++].entry);
+      label = (entry & MPLS_LS_LABEL_MASK) >> MPLS_LS_LABEL_SHIFT;
+      exp = (entry & MPLS_LS_TC_MASK) >> MPLS_LS_TC_SHIFT;
+      ttl = (entry & MPLS_LS_TTL_MASK) >> MPLS_LS_TTL_SHIFT;
+
+      fib_mpls_label_t fml = {
+	.fml_value = label,
+	.fml_exp = exp,
+	.fml_ttl = ttl,
+      };
+      vec_add1 (path->frp_label_stack, fml);
+
+      if (entry & MPLS_LS_S_MASK)
+	break;
+    }
+  return label_count;
+}
+
 static void
 lcp_nl_route_path_parse (struct rtnl_nexthop *rnh, void *arg)
 {
@@ -216,6 +288,7 @@ lcp_nl_route_path_parse (struct rtnl_nexthop *rnh, void *arg)
   lcp_itf_pair_t *lip;
   fib_protocol_t fproto;
   struct nl_addr *addr;
+  int label_count = 0;
 
   /* We do not log a warning/error here, because some routes (like
    * blackhole/unreach) don't have an interface associated with them.
@@ -230,9 +303,16 @@ lcp_nl_route_path_parse (struct rtnl_nexthop *rnh, void *arg)
 
   path->frp_flags = FIB_ROUTE_PATH_FLAG_NONE | ctx->type_flags;
   path->frp_sw_if_index = lip->lip_phy_sw_if_index;
-  path->frp_weight = rtnl_route_nh_get_weight (rnh);
   path->frp_preference = ctx->preference;
 
+  /*
+   * FIB Path Weight of 0 is meaningless and replaced with 1 further along.
+   * See fib_path_create. fib_path_cmp_w_route_path would fail to match
+   * such a fib_route_path_t with any fib_path_t, because a fib_path_t's
+   * fp_weight can never be 0.
+   */
+  path->frp_weight = clib_max (1, rtnl_route_nh_get_weight (rnh));
+
   addr = rtnl_route_nh_get_gateway (rnh);
   if (!addr)
     addr = rtnl_route_nh_get_via (rnh);
@@ -244,6 +324,32 @@ lcp_nl_route_path_parse (struct rtnl_nexthop *rnh, void *arg)
 
   path->frp_proto = fib_proto_to_dpo (fproto);
 
+  if (ctx->route_proto == FIB_PROTOCOL_MPLS)
+    {
+      addr = rtnl_route_nh_get_newdst (rnh);
+      label_count = lcp_router_mpls_nladdr_to_path (path, addr);
+      if (label_count)
+	{
+	  LCP_NL_DBG ("router_path_parse: is label swap to %u",
+		      path->frp_label_stack[0].fml_value);
+	}
+      else
+	{
+	  fib_mpls_label_t fml = {
+	    .fml_value = MPLS_LABEL_POP,
+	  };
+	  vec_add1 (path->frp_label_stack, fml);
+	  LCP_NL_DBG ("router_path_parse: is label pop");
+	}
+    }
+
+#ifdef NL_CAPABILITY_VERSION_3_6_0
+  addr = rtnl_route_nh_get_encap_mpls_dst (rnh);
+  label_count = lcp_router_mpls_nladdr_to_path (path, addr);
+  if (label_count)
+    LCP_NL_DBG ("router_path_parse: has encap mpls, %d labels", label_count);
+#endif
+
   if (ctx->is_mcast)
     path->frp_mitf_flags = MFIB_ITF_FLAG_FORWARD;
 
@@ -439,11 +545,21 @@ lcp_nl_route_del (struct rtnl_route *rr)
       LCP_NL_DBG ("route_del: table %d prefix %U flags %U",
 		  rtnl_route_get_table (rr), format_fib_prefix, &pfx,
 		  format_fib_entry_flags, entry_flags);
-      if (pfx.fp_proto == FIB_PROTOCOL_IP6)
+
+      switch (pfx.fp_proto)
+	{
+	case FIB_PROTOCOL_IP6:
 	  fib_table_entry_delete (nlt->nlt_fib_index, &pfx, fib_src);
-      else
+	  break;
+	case FIB_PROTOCOL_MPLS:
 	  fib_table_entry_path_remove2 (nlt->nlt_fib_index, &pfx, fib_src,
 					np.paths);
+	  /* delete the EOS route in addition to NEOS - fallthrough */
+	  pfx.fp_eos = MPLS_EOS;
+	default:
+	  fib_table_entry_path_remove2 (nlt->nlt_fib_index, &pfx, fib_src,
+					np.paths);
+	}
     }
 
   vec_free (np.paths);
@@ -451,6 +567,26 @@ lcp_nl_route_del (struct rtnl_route *rr)
   lcp_nl_table_unlock (nlt);
 }
 
+static fib_route_path_t *
+lcp_router_fib_route_path_dup (fib_route_path_t *old)
+{
+  int idx;
+  fib_route_path_t *p;
+
+  fib_route_path_t *new = vec_dup (old);
+  if (!new)
+    return NULL;
+
+  for (idx = 0; idx < vec_len (new); idx++)
+    {
+      p = &new[idx];
+      if (p->frp_label_stack)
+	p->frp_label_stack = vec_dup (p->frp_label_stack);
+    }
+
+  return new;
+}
+
 void
 lcp_nl_route_add (struct rtnl_route *rr, int is_replace)
 {
@@ -536,6 +672,24 @@ lcp_nl_route_add (struct rtnl_route *rr, int is_replace)
 		      rtnl_route_get_table (rr), format_fib_prefix, &pfx,
 		      format_fib_entry_flags, entry_flags);
 
+	  if (pfx.fp_proto == FIB_PROTOCOL_MPLS)
+	    {
+	      /* in order to avoid double-frees, we duplicate the paths. */
+	      fib_route_path_t *pathdup =
+		lcp_router_fib_route_path_dup (np.paths);
+	      if (is_replace)
+		fib_table_entry_update (nlt->nlt_fib_index, &pfx, fib_src,
+					entry_flags, pathdup);
+	      else
+		fib_table_entry_path_add2 (nlt->nlt_fib_index, &pfx, fib_src,
+					   entry_flags, pathdup);
+	      vec_free (pathdup);
+
+		/* install EOS route in addition to NEOS */
+		pfx.fp_eos = MPLS_EOS;
+	      pfx.fp_payload_proto = np.paths[0].frp_proto;
+	    }
+
 	  if (is_replace)
 	    fib_table_entry_update (nlt->nlt_fib_index, &pfx, fib_src,
 				    entry_flags, np.paths);