MPLS Mcast
[vpp.git] / src / vnet / ip / ip4_forward.c
index 8081b34..9fdf9b3 100644 (file)
@@ -75,7 +75,7 @@ ip4_lookup_inline (vlib_main_t * vm,
   vlib_combined_counter_main_t *cm = &load_balance_main.lbm_to_counters;
   u32 n_left_from, n_left_to_next, *from, *to_next;
   ip_lookup_next_t next;
-  u32 cpu_index = os_get_cpu_number ();
+  u32 thread_index = vlib_get_thread_index ();
 
   from = vlib_frame_vector_args (frame);
   n_left_from = frame->n_vectors;
@@ -95,14 +95,10 @@ ip4_lookup_inline (vlib_main_t * vm,
          ip4_fib_mtrie_t *mtrie0, *mtrie1, *mtrie2, *mtrie3;
          ip4_fib_mtrie_leaf_t leaf0, leaf1, leaf2, leaf3;
          ip4_address_t *dst_addr0, *dst_addr1, *dst_addr2, *dst_addr3;
-         __attribute__ ((unused)) u32 pi0, fib_index0, lb_index0,
-           is_tcp_udp0;
-         __attribute__ ((unused)) u32 pi1, fib_index1, lb_index1,
-           is_tcp_udp1;
-         __attribute__ ((unused)) u32 pi2, fib_index2, lb_index2,
-           is_tcp_udp2;
-         __attribute__ ((unused)) u32 pi3, fib_index3, lb_index3,
-           is_tcp_udp3;
+         u32 pi0, fib_index0, lb_index0;
+         u32 pi1, fib_index1, lb_index1;
+         u32 pi2, fib_index2, lb_index2;
+         u32 pi3, fib_index3, lb_index3;
          flow_hash_config_t flow_hash_config0, flow_hash_config1;
          flow_hash_config_t flow_hash_config2, flow_hash_config3;
          u32 hash_c0, hash_c1, hash_c2, hash_c3;
@@ -186,12 +182,10 @@ ip4_lookup_inline (vlib_main_t * vm,
              mtrie2 = &ip4_fib_get (fib_index2)->mtrie;
              mtrie3 = &ip4_fib_get (fib_index3)->mtrie;
 
-             leaf0 = leaf1 = leaf2 = leaf3 = IP4_FIB_MTRIE_LEAF_ROOT;
-
-             leaf0 = ip4_fib_mtrie_lookup_step (mtrie0, leaf0, dst_addr0, 0);
-             leaf1 = ip4_fib_mtrie_lookup_step (mtrie1, leaf1, dst_addr1, 0);
-             leaf2 = ip4_fib_mtrie_lookup_step (mtrie2, leaf2, dst_addr2, 0);
-             leaf3 = ip4_fib_mtrie_lookup_step (mtrie3, leaf3, dst_addr3, 0);
+             leaf0 = ip4_fib_mtrie_lookup_step_one (mtrie0, dst_addr0);
+             leaf1 = ip4_fib_mtrie_lookup_step_one (mtrie1, dst_addr1);
+             leaf2 = ip4_fib_mtrie_lookup_step_one (mtrie2, dst_addr2);
+             leaf3 = ip4_fib_mtrie_lookup_step_one (mtrie3, dst_addr3);
            }
 
          tcp0 = (void *) (ip0 + 1);
@@ -199,23 +193,6 @@ ip4_lookup_inline (vlib_main_t * vm,
          tcp2 = (void *) (ip2 + 1);
          tcp3 = (void *) (ip3 + 1);
 
-         is_tcp_udp0 = (ip0->protocol == IP_PROTOCOL_TCP
-                        || ip0->protocol == IP_PROTOCOL_UDP);
-         is_tcp_udp1 = (ip1->protocol == IP_PROTOCOL_TCP
-                        || ip1->protocol == IP_PROTOCOL_UDP);
-         is_tcp_udp2 = (ip2->protocol == IP_PROTOCOL_TCP
-                        || ip2->protocol == IP_PROTOCOL_UDP);
-         is_tcp_udp3 = (ip1->protocol == IP_PROTOCOL_TCP
-                        || ip1->protocol == IP_PROTOCOL_UDP);
-
-         if (!lookup_for_responses_to_locally_received_packets)
-           {
-             leaf0 = ip4_fib_mtrie_lookup_step (mtrie0, leaf0, dst_addr0, 1);
-             leaf1 = ip4_fib_mtrie_lookup_step (mtrie1, leaf1, dst_addr1, 1);
-             leaf2 = ip4_fib_mtrie_lookup_step (mtrie2, leaf2, dst_addr2, 1);
-             leaf3 = ip4_fib_mtrie_lookup_step (mtrie3, leaf3, dst_addr3, 1);
-           }
-
          if (!lookup_for_responses_to_locally_received_packets)
            {
              leaf0 = ip4_fib_mtrie_lookup_step (mtrie0, leaf0, dst_addr0, 2);
@@ -241,25 +218,13 @@ ip4_lookup_inline (vlib_main_t * vm,
            }
          else
            {
-             /* Handle default route. */
-             leaf0 =
-               (leaf0 ==
-                IP4_FIB_MTRIE_LEAF_EMPTY ? mtrie0->default_leaf : leaf0);
-             leaf1 =
-               (leaf1 ==
-                IP4_FIB_MTRIE_LEAF_EMPTY ? mtrie1->default_leaf : leaf1);
-             leaf2 =
-               (leaf2 ==
-                IP4_FIB_MTRIE_LEAF_EMPTY ? mtrie2->default_leaf : leaf2);
-             leaf3 =
-               (leaf3 ==
-                IP4_FIB_MTRIE_LEAF_EMPTY ? mtrie3->default_leaf : leaf3);
              lb_index0 = ip4_fib_mtrie_leaf_get_adj_index (leaf0);
              lb_index1 = ip4_fib_mtrie_leaf_get_adj_index (leaf1);
              lb_index2 = ip4_fib_mtrie_leaf_get_adj_index (leaf2);
              lb_index3 = ip4_fib_mtrie_leaf_get_adj_index (leaf3);
            }
 
+         ASSERT (lb_index0 && lb_index1 && lb_index2 && lb_index3);
          lb0 = load_balance_get (lb_index0);
          lb1 = load_balance_get (lb_index1);
          lb2 = load_balance_get (lb_index2);
@@ -327,19 +292,19 @@ ip4_lookup_inline (vlib_main_t * vm,
          vnet_buffer (p3)->ip.adj_index[VLIB_TX] = dpo3->dpoi_index;
 
          vlib_increment_combined_counter
-           (cm, cpu_index, lb_index0, 1,
+           (cm, thread_index, lb_index0, 1,
             vlib_buffer_length_in_chain (vm, p0)
             + sizeof (ethernet_header_t));
          vlib_increment_combined_counter
-           (cm, cpu_index, lb_index1, 1,
+           (cm, thread_index, lb_index1, 1,
             vlib_buffer_length_in_chain (vm, p1)
             + sizeof (ethernet_header_t));
          vlib_increment_combined_counter
-           (cm, cpu_index, lb_index2, 1,
+           (cm, thread_index, lb_index2, 1,
             vlib_buffer_length_in_chain (vm, p2)
             + sizeof (ethernet_header_t));
          vlib_increment_combined_counter
-           (cm, cpu_index, lb_index3, 1,
+           (cm, thread_index, lb_index3, 1,
             vlib_buffer_length_in_chain (vm, p3)
             + sizeof (ethernet_header_t));
 
@@ -359,7 +324,7 @@ ip4_lookup_inline (vlib_main_t * vm,
          ip4_fib_mtrie_t *mtrie0;
          ip4_fib_mtrie_leaf_t leaf0;
          ip4_address_t *dst_addr0;
-         __attribute__ ((unused)) u32 pi0, fib_index0, is_tcp_udp0, lbi0;
+         u32 pi0, fib_index0, lbi0;
          flow_hash_config_t flow_hash_config0;
          const dpo_id_t *dpo0;
          u32 hash_c0;
@@ -384,19 +349,11 @@ ip4_lookup_inline (vlib_main_t * vm,
            {
              mtrie0 = &ip4_fib_get (fib_index0)->mtrie;
 
-             leaf0 = IP4_FIB_MTRIE_LEAF_ROOT;
-
-             leaf0 = ip4_fib_mtrie_lookup_step (mtrie0, leaf0, dst_addr0, 0);
+             leaf0 = ip4_fib_mtrie_lookup_step_one (mtrie0, dst_addr0);
            }
 
          tcp0 = (void *) (ip0 + 1);
 
-         is_tcp_udp0 = (ip0->protocol == IP_PROTOCOL_TCP
-                        || ip0->protocol == IP_PROTOCOL_UDP);
-
-         if (!lookup_for_responses_to_locally_received_packets)
-           leaf0 = ip4_fib_mtrie_lookup_step (mtrie0, leaf0, dst_addr0, 1);
-
          if (!lookup_for_responses_to_locally_received_packets)
            leaf0 = ip4_fib_mtrie_lookup_step (mtrie0, leaf0, dst_addr0, 2);
 
@@ -408,12 +365,10 @@ ip4_lookup_inline (vlib_main_t * vm,
          else
            {
              /* Handle default route. */
-             leaf0 =
-               (leaf0 ==
-                IP4_FIB_MTRIE_LEAF_EMPTY ? mtrie0->default_leaf : leaf0);
              lbi0 = ip4_fib_mtrie_leaf_get_adj_index (leaf0);
            }
 
+         ASSERT (lbi0);
          lb0 = load_balance_get (lbi0);
 
          /* Use flow hash to compute multipath adjacency. */
@@ -437,7 +392,7 @@ ip4_lookup_inline (vlib_main_t * vm,
          vnet_buffer (p0)->ip.adj_index[VLIB_TX] = dpo0->dpoi_index;
 
          vlib_increment_combined_counter
-           (cm, cpu_index, lbi0, 1, vlib_buffer_length_in_chain (vm, p0));
+           (cm, thread_index, lbi0, 1, vlib_buffer_length_in_chain (vm, p0));
 
          from += 1;
          to_next += 1;
@@ -524,7 +479,7 @@ ip4_load_balance (vlib_main_t * vm,
   vlib_combined_counter_main_t *cm = &load_balance_main.lbm_via_counters;
   u32 n_left_from, n_left_to_next, *from, *to_next;
   ip_lookup_next_t next;
-  u32 cpu_index = os_get_cpu_number ();
+  u32 thread_index = vlib_get_thread_index ();
 
   from = vlib_frame_vector_args (frame);
   n_left_from = frame->n_vectors;
@@ -586,8 +541,7 @@ ip4_load_balance (vlib_main_t * vm,
           * We don't want to use the same hash value at each level in the recursion
           * graph as that would lead to polarisation
           */
-         hc0 = vnet_buffer (p0)->ip.flow_hash = 0;
-         hc1 = vnet_buffer (p1)->ip.flow_hash = 0;
+         hc0 = hc1 = 0;
 
          if (PREDICT_FALSE (lb0->lb_n_buckets > 1))
            {
@@ -599,7 +553,7 @@ ip4_load_balance (vlib_main_t * vm,
              else
                {
                  hc0 = vnet_buffer (p0)->ip.flow_hash =
-                   ip4_compute_flow_hash (ip0, hc0);
+                   ip4_compute_flow_hash (ip0, lb0->lb_hash_config);
                }
            }
          if (PREDICT_FALSE (lb1->lb_n_buckets > 1))
@@ -612,7 +566,7 @@ ip4_load_balance (vlib_main_t * vm,
              else
                {
                  hc1 = vnet_buffer (p1)->ip.flow_hash =
-                   ip4_compute_flow_hash (ip1, hc1);
+                   ip4_compute_flow_hash (ip1, lb1->lb_hash_config);
                }
            }
 
@@ -630,9 +584,9 @@ ip4_load_balance (vlib_main_t * vm,
          vnet_buffer (p1)->ip.adj_index[VLIB_TX] = dpo1->dpoi_index;
 
          vlib_increment_combined_counter
-           (cm, cpu_index, lbi0, 1, vlib_buffer_length_in_chain (vm, p0));
+           (cm, thread_index, lbi0, 1, vlib_buffer_length_in_chain (vm, p0));
          vlib_increment_combined_counter
-           (cm, cpu_index, lbi1, 1, vlib_buffer_length_in_chain (vm, p1));
+           (cm, thread_index, lbi1, 1, vlib_buffer_length_in_chain (vm, p1));
 
          vlib_validate_buffer_enqueue_x2 (vm, node, next,
                                           to_next, n_left_to_next,
@@ -662,7 +616,7 @@ ip4_load_balance (vlib_main_t * vm,
 
          lb0 = load_balance_get (lbi0);
 
-         hc0 = vnet_buffer (p0)->ip.flow_hash = 0;
+         hc0 = 0;
          if (PREDICT_FALSE (lb0->lb_n_buckets > 1))
            {
              if (PREDICT_TRUE (vnet_buffer (p0)->ip.flow_hash))
@@ -673,7 +627,7 @@ ip4_load_balance (vlib_main_t * vm,
              else
                {
                  hc0 = vnet_buffer (p0)->ip.flow_hash =
-                   ip4_compute_flow_hash (ip0, hc0);
+                   ip4_compute_flow_hash (ip0, lb0->lb_hash_config);
                }
            }
 
@@ -685,7 +639,7 @@ ip4_load_balance (vlib_main_t * vm,
          vnet_buffer (p0)->ip.adj_index[VLIB_TX] = dpo0->dpoi_index;
 
          vlib_increment_combined_counter
-           (cm, cpu_index, lbi0, 1, vlib_buffer_length_in_chain (vm, p0));
+           (cm, thread_index, lbi0, 1, vlib_buffer_length_in_chain (vm, p0));
 
          vlib_validate_buffer_enqueue_x1 (vm, node, next,
                                           to_next, n_left_to_next,
@@ -746,8 +700,9 @@ ip4_add_interface_routes (u32 sw_if_index,
 
   a->neighbor_probe_adj_index = ~0;
 
-  if (pfx.fp_len < 32)
+  if (pfx.fp_len <= 30)
     {
+      /* a /30 or shorter - add a glean for the network address */
       fib_node_index_t fei;
 
       fei = fib_table_entry_update_one_path (fib_index, &pfx,
@@ -765,8 +720,50 @@ ip4_add_interface_routes (u32 sw_if_index,
                                              NULL,
                                             FIB_ROUTE_PATH_FLAG_NONE);
       a->neighbor_probe_adj_index = fib_entry_get_adj (fei);
-    }
 
+      /* Add the two broadcast addresses as drop */
+      fib_prefix_t net_pfx = {
+        .fp_len = 32,
+        .fp_proto = FIB_PROTOCOL_IP4,
+        .fp_addr.ip4.as_u32 = address->as_u32 & im->fib_masks[pfx.fp_len],
+      };
+      if (net_pfx.fp_addr.ip4.as_u32 != pfx.fp_addr.ip4.as_u32)
+        fib_table_entry_special_add(fib_index,
+                                    &net_pfx,
+                                    FIB_SOURCE_INTERFACE,
+                                    (FIB_ENTRY_FLAG_DROP |
+                                     FIB_ENTRY_FLAG_LOOSE_URPF_EXEMPT),
+                                    ADJ_INDEX_INVALID);
+      net_pfx.fp_addr.ip4.as_u32 |= ~im->fib_masks[pfx.fp_len];
+      if (net_pfx.fp_addr.ip4.as_u32 != pfx.fp_addr.ip4.as_u32)
+        fib_table_entry_special_add(fib_index,
+                                    &net_pfx,
+                                    FIB_SOURCE_INTERFACE,
+                                    (FIB_ENTRY_FLAG_DROP |
+                                     FIB_ENTRY_FLAG_LOOSE_URPF_EXEMPT),
+                                    ADJ_INDEX_INVALID);
+    }
+  else if (pfx.fp_len == 31)
+    {
+      u32 mask = clib_host_to_net_u32(1);
+      fib_prefix_t net_pfx = pfx;
+
+      net_pfx.fp_len = 32;
+      net_pfx.fp_addr.ip4.as_u32 ^= mask;
+
+      /* a /31 - add the other end as an attached host */
+      fib_table_entry_update_one_path (fib_index, &net_pfx,
+                                       FIB_SOURCE_INTERFACE,
+                                       (FIB_ENTRY_FLAG_ATTACHED),
+                                       FIB_PROTOCOL_IP4,
+                                       &net_pfx.fp_addr,
+                                       sw_if_index,
+                                       // invalid FIB index
+                                       ~0,
+                                       1,
+                                       NULL,
+                                       FIB_ROUTE_PATH_FLAG_NONE);
+    }
   pfx.fp_len = 32;
 
   if (sw_if_index < vec_len (lm->classify_table_index_by_sw_if_index))
@@ -814,10 +811,34 @@ ip4_del_interface_routes (ip4_main_t * im,
     .fp_addr.ip4 = *address,
   };
 
-  if (pfx.fp_len < 32)
+  if (pfx.fp_len <= 30)
     {
+      fib_prefix_t net_pfx = {
+        .fp_len = 32,
+        .fp_proto = FIB_PROTOCOL_IP4,
+        .fp_addr.ip4.as_u32 = address->as_u32 & im->fib_masks[pfx.fp_len],
+      };
+      if (net_pfx.fp_addr.ip4.as_u32 != pfx.fp_addr.ip4.as_u32)
+        fib_table_entry_special_remove(fib_index,
+                                       &net_pfx,
+                                       FIB_SOURCE_INTERFACE);
+      net_pfx.fp_addr.ip4.as_u32 |= ~im->fib_masks[pfx.fp_len];
+      if (net_pfx.fp_addr.ip4.as_u32 != pfx.fp_addr.ip4.as_u32)
+        fib_table_entry_special_remove(fib_index,
+                                       &net_pfx,
+                                       FIB_SOURCE_INTERFACE);
       fib_table_entry_delete (fib_index, &pfx, FIB_SOURCE_INTERFACE);
     }
+    else if (pfx.fp_len == 31)
+    {
+      u32 mask = clib_host_to_net_u32(1);
+      fib_prefix_t net_pfx = pfx;
+
+      net_pfx.fp_len = 32;
+      net_pfx.fp_addr.ip4.as_u32 ^= mask;
+
+      fib_table_entry_delete (fib_index, &net_pfx, FIB_SOURCE_INTERFACE);
+    }
 
   pfx.fp_len = 32;
   fib_table_entry_delete (fib_index, &pfx, FIB_SOURCE_INTERFACE);
@@ -848,9 +869,8 @@ ip4_sw_interface_enable_disable (u32 sw_if_index, u32 is_enable)
                               !is_enable, 0, 0);
 
 
-  vnet_feature_enable_disable ("ip4-multicast",
-                              "ip4-mfib-forward-lookup",
-                              sw_if_index, is_enable, 0, 0);
+  vnet_feature_enable_disable ("ip4-multicast", "ip4-drop",
+                              sw_if_index, !is_enable, 0, 0);
 }
 
 static clib_error_t *
@@ -955,7 +975,6 @@ VNET_FEATURE_ARC_INIT (ip4_unicast, static) =
 {
   .arc_name = "ip4-unicast",
   .start_nodes = VNET_FEATURES ("ip4-input", "ip4-input-no-checksum"),
-  .end_node = "ip4-lookup",
   .arc_index_ptr = &ip4_main.lookup_main.ucast_feature_arc_index,
 };
 
@@ -1022,27 +1041,25 @@ VNET_FEATURE_INIT (ip4_vxlan_bypass, static) =
   .runs_before = VNET_FEATURES ("ip4-lookup"),
 };
 
-VNET_FEATURE_INIT (ip4_lookup, static) =
+VNET_FEATURE_INIT (ip4_drop, static) =
 {
   .arc_name = "ip4-unicast",
-  .node_name = "ip4-lookup",
-  .runs_before = VNET_FEATURES ("ip4-drop"),
+  .node_name = "ip4-drop",
+  .runs_before = VNET_FEATURES ("ip4-lookup"),
 };
 
-VNET_FEATURE_INIT (ip4_drop, static) =
+VNET_FEATURE_INIT (ip4_lookup, static) =
 {
   .arc_name = "ip4-unicast",
-  .node_name = "ip4-drop",
+  .node_name = "ip4-lookup",
   .runs_before = 0,    /* not before any other features */
 };
 
-
 /* Built-in ip4 multicast rx feature path definition */
 VNET_FEATURE_ARC_INIT (ip4_multicast, static) =
 {
   .arc_name = "ip4-multicast",
   .start_nodes = VNET_FEATURES ("ip4-input", "ip4-input-no-checksum"),
-  .end_node = "ip4-lookup-multicast",
   .arc_index_ptr = &ip4_main.lookup_main.mcast_feature_arc_index,
 };
 
@@ -1053,17 +1070,17 @@ VNET_FEATURE_INIT (ip4_vpath_mc, static) =
   .runs_before = VNET_FEATURES ("ip4-mfib-forward-lookup"),
 };
 
-VNET_FEATURE_INIT (ip4_lookup_mc, static) =
+VNET_FEATURE_INIT (ip4_mc_drop, static) =
 {
   .arc_name = "ip4-multicast",
-  .node_name = "ip4-mfib-forward-lookup",
-  .runs_before = VNET_FEATURES ("ip4-drop"),
+  .node_name = "ip4-drop",
+  .runs_before = VNET_FEATURES ("ip4-mfib-forward-lookup"),
 };
 
-VNET_FEATURE_INIT (ip4_mc_drop, static) =
+VNET_FEATURE_INIT (ip4_lookup_mc, static) =
 {
   .arc_name = "ip4-multicast",
-  .node_name = "ip4-drop",
+  .node_name = "ip4-mfib-forward-lookup",
   .runs_before = 0,    /* last feature */
 };
 
@@ -1072,7 +1089,6 @@ VNET_FEATURE_ARC_INIT (ip4_output, static) =
 {
   .arc_name = "ip4-output",
   .start_nodes = VNET_FEATURES ("ip4-rewrite", "ip4-midchain"),
-  .end_node = "interface-output",
   .arc_index_ptr = &ip4_main.lookup_main.output_feature_arc_index,
 };
 
@@ -1233,7 +1249,6 @@ format_ip4_rewrite_trace (u8 * s, va_list * args)
   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
   ip4_forward_next_trace_t *t = va_arg (*args, ip4_forward_next_trace_t *);
-  vnet_main_t *vnm = vnet_get_main ();
   uword indent = format_get_indent (s);
 
   s = format (s, "tx_sw_if_index %d dpo-idx %d : %U flow hash: 0x%08x",
@@ -1242,7 +1257,7 @@ format_ip4_rewrite_trace (u8 * s, va_list * args)
   s = format (s, "\n%U%U",
              format_white_space, indent,
              format_ip_adjacency_packet_data,
-             vnm, t->dpo_index, t->packet_data, sizeof (t->packet_data));
+             t->dpo_index, t->packet_data, sizeof (t->packet_data));
   return s;
 }
 
@@ -1478,8 +1493,18 @@ ip4_tcp_udp_validate_checksum (vlib_main_t * vm, vlib_buffer_t * p0)
   return p0->flags;
 }
 
-static uword
-ip4_local (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
+/* *INDENT-OFF* */
+VNET_FEATURE_ARC_INIT (ip4_local) =
+{
+  .arc_name  = "ip4-local",
+  .start_nodes = VNET_FEATURES ("ip4-local"),
+};
+/* *INDENT-ON* */
+
+static inline uword
+ip4_local_inline (vlib_main_t * vm,
+                 vlib_node_runtime_t * node,
+                 vlib_frame_t * frame, int head_of_feature_arc)
 {
   ip4_main_t *im = &ip4_main;
   ip_lookup_main_t *lm = &im->lookup_main;
@@ -1487,6 +1512,7 @@ ip4_local (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
   u32 *from, *to_next, n_left_from, n_left_to_next;
   vlib_node_runtime_t *error_node =
     vlib_node_get_runtime (vm, ip4_input_node.index);
+  u8 arc_index = vnet_feat_arc_ip4_local.feature_arc_index;
 
   from = vlib_frame_vector_args (frame);
   n_left_from = frame->n_vectors;
@@ -1513,7 +1539,7 @@ ip4_local (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
          i32 len_diff0, len_diff1;
          u8 error0, is_udp0, is_tcp_udp0, good_tcp_udp0, proto0;
          u8 error1, is_udp1, is_tcp_udp1, good_tcp_udp1, proto1;
-         u8 enqueue_code;
+         u32 sw_if_index0, sw_if_index1;
 
          pi0 = to_next[0] = from[0];
          pi1 = to_next[1] = from[1];
@@ -1522,6 +1548,8 @@ ip4_local (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
          to_next += 2;
          n_left_to_next -= 2;
 
+         next0 = next1 = IP_LOCAL_NEXT_DROP;
+
          p0 = vlib_get_buffer (vm, pi0);
          p1 = vlib_get_buffer (vm, pi1);
 
@@ -1531,14 +1559,18 @@ ip4_local (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
          vnet_buffer (p0)->ip.start_of_ip_header = p0->current_data;
          vnet_buffer (p1)->ip.start_of_ip_header = p1->current_data;
 
-         fib_index0 = vec_elt (im->fib_index_by_sw_if_index,
-                               vnet_buffer (p0)->sw_if_index[VLIB_RX]);
+         sw_if_index0 = vnet_buffer (p0)->sw_if_index[VLIB_RX];
+         sw_if_index1 = vnet_buffer (p1)->sw_if_index[VLIB_RX];
+
+         fib_index0 = vec_elt (im->fib_index_by_sw_if_index, sw_if_index0);
+         fib_index1 = vec_elt (im->fib_index_by_sw_if_index, sw_if_index1);
+
+         fib_index0 = vec_elt (im->fib_index_by_sw_if_index, sw_if_index0);
          fib_index0 =
            (vnet_buffer (p0)->sw_if_index[VLIB_TX] ==
             (u32) ~ 0) ? fib_index0 : vnet_buffer (p0)->sw_if_index[VLIB_TX];
 
-         fib_index1 = vec_elt (im->fib_index_by_sw_if_index,
-                               vnet_buffer (p1)->sw_if_index[VLIB_RX]);
+         fib_index1 = vec_elt (im->fib_index_by_sw_if_index, sw_if_index1);
          fib_index1 =
            (vnet_buffer (p1)->sw_if_index[VLIB_TX] ==
             (u32) ~ 0) ? fib_index1 : vnet_buffer (p1)->sw_if_index[VLIB_TX];
@@ -1546,17 +1578,20 @@ ip4_local (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
          mtrie0 = &ip4_fib_get (fib_index0)->mtrie;
          mtrie1 = &ip4_fib_get (fib_index1)->mtrie;
 
-         leaf0 = leaf1 = IP4_FIB_MTRIE_LEAF_ROOT;
-
-         leaf0 =
-           ip4_fib_mtrie_lookup_step (mtrie0, leaf0, &ip0->src_address, 0);
-         leaf1 =
-           ip4_fib_mtrie_lookup_step (mtrie1, leaf1, &ip1->src_address, 0);
+         leaf0 = ip4_fib_mtrie_lookup_step_one (mtrie0, &ip0->src_address);
+         leaf1 = ip4_fib_mtrie_lookup_step_one (mtrie1, &ip1->src_address);
 
          /* Treat IP frag packets as "experimental" protocol for now
             until support of IP frag reassembly is implemented */
          proto0 = ip4_is_fragment (ip0) ? 0xfe : ip0->protocol;
          proto1 = ip4_is_fragment (ip1) ? 0xfe : ip1->protocol;
+
+         if (head_of_feature_arc == 0)
+           {
+             error0 = error1 = IP4_ERROR_UNKNOWN_PROTOCOL;
+             goto skip_checks;
+           }
+
          is_udp0 = proto0 == IP_PROTOCOL_UDP;
          is_udp1 = proto1 == IP_PROTOCOL_UDP;
          is_tcp_udp0 = is_udp0 || proto0 == IP_PROTOCOL_TCP;
@@ -1575,11 +1610,6 @@ ip4_local (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
          good_tcp_udp0 |= is_udp0 && udp0->checksum == 0;
          good_tcp_udp1 |= is_udp1 && udp1->checksum == 0;
 
-         leaf0 =
-           ip4_fib_mtrie_lookup_step (mtrie0, leaf0, &ip0->src_address, 1);
-         leaf1 =
-           ip4_fib_mtrie_lookup_step (mtrie1, leaf1, &ip1->src_address, 1);
-
          /* Verify UDP length. */
          ip_len0 = clib_net_to_host_u16 (ip0->length);
          ip_len1 = clib_net_to_host_u16 (ip1->length);
@@ -1638,12 +1668,6 @@ ip4_local (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
            ip4_fib_mtrie_lookup_step (mtrie0, leaf0, &ip0->src_address, 3);
          leaf1 =
            ip4_fib_mtrie_lookup_step (mtrie1, leaf1, &ip1->src_address, 3);
-         leaf0 =
-           (leaf0 ==
-            IP4_FIB_MTRIE_LEAF_EMPTY ? mtrie0->default_leaf : leaf0);
-         leaf1 =
-           (leaf1 ==
-            IP4_FIB_MTRIE_LEAF_EMPTY ? mtrie1->default_leaf : leaf1);
 
          vnet_buffer (p0)->ip.adj_index[VLIB_RX] = lbi0 =
            ip4_fib_mtrie_leaf_get_adj_index (leaf0);
@@ -1683,6 +1707,8 @@ ip4_local (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
                     ip1->dst_address.as_u32 != 0xFFFFFFFF)
                    ? IP4_ERROR_SRC_LOOKUP_MISS : error1);
 
+       skip_checks:
+
          next0 = lm->local_next_by_ip_protocol[proto0];
          next1 = lm->local_next_by_ip_protocol[proto1];
 
@@ -1694,44 +1720,17 @@ ip4_local (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
          p0->error = error0 ? error_node->errors[error0] : 0;
          p1->error = error1 ? error_node->errors[error1] : 0;
 
-         enqueue_code = (next0 != next_index) + 2 * (next1 != next_index);
-
-         if (PREDICT_FALSE (enqueue_code != 0))
+         if (head_of_feature_arc)
            {
-             switch (enqueue_code)
-               {
-               case 1:
-                 /* A B A */
-                 to_next[-2] = pi1;
-                 to_next -= 1;
-                 n_left_to_next += 1;
-                 vlib_set_next_frame_buffer (vm, node, next0, pi0);
-                 break;
-
-               case 2:
-                 /* A A B */
-                 to_next -= 1;
-                 n_left_to_next += 1;
-                 vlib_set_next_frame_buffer (vm, node, next1, pi1);
-                 break;
-
-               case 3:
-                 /* A B B or A B C */
-                 to_next -= 2;
-                 n_left_to_next += 2;
-                 vlib_set_next_frame_buffer (vm, node, next0, pi0);
-                 vlib_set_next_frame_buffer (vm, node, next1, pi1);
-                 if (next0 == next1)
-                   {
-                     vlib_put_next_frame (vm, node, next_index,
-                                          n_left_to_next);
-                     next_index = next1;
-                     vlib_get_next_frame (vm, node, next_index, to_next,
-                                          n_left_to_next);
-                   }
-                 break;
-               }
+             if (PREDICT_TRUE (error0 == (u8) IP4_ERROR_UNKNOWN_PROTOCOL))
+               vnet_feature_arc_start (arc_index, sw_if_index0, &next0, p0);
+             if (PREDICT_TRUE (error1 == (u8) IP4_ERROR_UNKNOWN_PROTOCOL))
+               vnet_feature_arc_start (arc_index, sw_if_index1, &next1, p1);
            }
+
+         vlib_validate_buffer_enqueue_x2 (vm, node, next_index, to_next,
+                                          n_left_to_next, pi0, pi1,
+                                          next0, next1);
        }
 
       while (n_left_from > 0 && n_left_to_next > 0)
@@ -1746,6 +1745,7 @@ ip4_local (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
          u8 error0, is_udp0, is_tcp_udp0, good_tcp_udp0, proto0;
          load_balance_t *lb0;
          const dpo_id_t *dpo0;
+         u32 sw_if_index0;
 
          pi0 = to_next[0] = from[0];
          from += 1;
@@ -1753,28 +1753,36 @@ ip4_local (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
          to_next += 1;
          n_left_to_next -= 1;
 
+         next0 = IP_LOCAL_NEXT_DROP;
+
          p0 = vlib_get_buffer (vm, pi0);
 
          ip0 = vlib_buffer_get_current (p0);
 
          vnet_buffer (p0)->ip.start_of_ip_header = p0->current_data;
 
-         fib_index0 = vec_elt (im->fib_index_by_sw_if_index,
-                               vnet_buffer (p0)->sw_if_index[VLIB_RX]);
+         sw_if_index0 = vnet_buffer (p0)->sw_if_index[VLIB_RX];
+
+         fib_index0 = vec_elt (im->fib_index_by_sw_if_index, sw_if_index0);
+
          fib_index0 =
            (vnet_buffer (p0)->sw_if_index[VLIB_TX] ==
             (u32) ~ 0) ? fib_index0 : vnet_buffer (p0)->sw_if_index[VLIB_TX];
 
          mtrie0 = &ip4_fib_get (fib_index0)->mtrie;
 
-         leaf0 = IP4_FIB_MTRIE_LEAF_ROOT;
-
-         leaf0 =
-           ip4_fib_mtrie_lookup_step (mtrie0, leaf0, &ip0->src_address, 0);
+         leaf0 = ip4_fib_mtrie_lookup_step_one (mtrie0, &ip0->src_address);
 
          /* Treat IP frag packets as "experimental" protocol for now
             until support of IP frag reassembly is implemented */
          proto0 = ip4_is_fragment (ip0) ? 0xfe : ip0->protocol;
+
+         if (head_of_feature_arc == 0)
+           {
+             error0 = IP4_ERROR_UNKNOWN_PROTOCOL;
+             goto skip_check;
+           }
+
          is_udp0 = proto0 == IP_PROTOCOL_UDP;
          is_tcp_udp0 = is_udp0 || proto0 == IP_PROTOCOL_TCP;
 
@@ -1787,9 +1795,6 @@ ip4_local (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
          /* Don't verify UDP checksum for packets with explicit zero checksum. */
          good_tcp_udp0 |= is_udp0 && udp0->checksum == 0;
 
-         leaf0 =
-           ip4_fib_mtrie_lookup_step (mtrie0, leaf0, &ip0->src_address, 1);
-
          /* Verify UDP length. */
          ip_len0 = clib_net_to_host_u16 (ip0->length);
          udp_len0 = clib_net_to_host_u16 (udp0->length);
@@ -1826,9 +1831,6 @@ ip4_local (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
 
          leaf0 =
            ip4_fib_mtrie_lookup_step (mtrie0, leaf0, &ip0->src_address, 3);
-         leaf0 =
-           (leaf0 ==
-            IP4_FIB_MTRIE_LEAF_EMPTY ? mtrie0->default_leaf : leaf0);
 
          lbi0 = ip4_fib_mtrie_leaf_get_adj_index (leaf0);
          vnet_buffer (p0)->ip.adj_index[VLIB_TX] = lbi0;
@@ -1847,6 +1849,8 @@ ip4_local (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
                     ip0->dst_address.as_u32 != 0xFFFFFFFF)
                    ? IP4_ERROR_SRC_LOOKUP_MISS : error0);
 
+       skip_check:
+
          next0 = lm->local_next_by_ip_protocol[proto0];
 
          next0 =
@@ -1854,18 +1858,15 @@ ip4_local (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
 
          p0->error = error0 ? error_node->errors[error0] : 0;
 
-         if (PREDICT_FALSE (next0 != next_index))
+         if (head_of_feature_arc)
            {
-             n_left_to_next += 1;
-             vlib_put_next_frame (vm, node, next_index, n_left_to_next);
-
-             next_index = next0;
-             vlib_get_next_frame (vm, node, next_index, to_next,
-                                  n_left_to_next);
-             to_next[0] = pi0;
-             to_next += 1;
-             n_left_to_next -= 1;
+             if (PREDICT_TRUE (error0 == (u8) IP4_ERROR_UNKNOWN_PROTOCOL))
+               vnet_feature_arc_start (arc_index, sw_if_index0, &next0, p0);
            }
+
+         vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
+                                          n_left_to_next, pi0, next0);
+
        }
 
       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
@@ -1874,21 +1875,57 @@ ip4_local (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
   return frame->n_vectors;
 }
 
+static uword
+ip4_local (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+  return ip4_local_inline (vm, node, frame, 1 /* head of feature arc */ );
+}
+
+/* *INDENT-OFF* */
 VLIB_REGISTER_NODE (ip4_local_node) =
 {
-  .function = ip4_local,.name = "ip4-local",.vector_size =
-    sizeof (u32),.format_trace =
-    format_ip4_forward_next_trace,.n_next_nodes =
-    IP_LOCAL_N_NEXT,.next_nodes =
+  .function = ip4_local,
+  .name = "ip4-local",
+  .vector_size = sizeof (u32),
+  .format_trace = format_ip4_forward_next_trace,
+  .n_next_nodes = IP_LOCAL_N_NEXT,
+  .next_nodes =
   {
-  [IP_LOCAL_NEXT_DROP] = "error-drop",
-      [IP_LOCAL_NEXT_PUNT] = "error-punt",
-      [IP_LOCAL_NEXT_UDP_LOOKUP] = "ip4-udp-lookup",
-      [IP_LOCAL_NEXT_ICMP] = "ip4-icmp-input",}
-,};
+    [IP_LOCAL_NEXT_DROP] = "error-drop",
+    [IP_LOCAL_NEXT_PUNT] = "error-punt",
+    [IP_LOCAL_NEXT_UDP_LOOKUP] = "ip4-udp-lookup",
+    [IP_LOCAL_NEXT_ICMP] = "ip4-icmp-input",},
+};
+/* *INDENT-ON* */
 
 VLIB_NODE_FUNCTION_MULTIARCH (ip4_local_node, ip4_local);
 
+static uword
+ip4_local_end_of_arc (vlib_main_t * vm,
+                     vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+  return ip4_local_inline (vm, node, frame, 0 /* head of feature arc */ );
+}
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (ip4_local_end_of_arc_node,static) = {
+  .function = ip4_local_end_of_arc,
+  .name = "ip4-local-end-of-arc",
+  .vector_size = sizeof (u32),
+
+  .format_trace = format_ip4_forward_next_trace,
+  .sibling_of = "ip4-local",
+};
+
+VLIB_NODE_FUNCTION_MULTIARCH (ip4_local_end_of_arc_node, ip4_local_end_of_arc)
+
+VNET_FEATURE_INIT (ip4_local_end_of_arc, static) = {
+  .arc_name = "ip4-local",
+  .node_name = "ip4-local-end-of-arc",
+  .runs_before = 0, /* not before any other features */
+};
+/* *INDENT-ON* */
+
 void
 ip4_register_protocol (u32 protocol, u32 node_index)
 {
@@ -2282,7 +2319,8 @@ typedef enum
 always_inline uword
 ip4_rewrite_inline (vlib_main_t * vm,
                    vlib_node_runtime_t * node,
-                   vlib_frame_t * frame, int is_midchain, int is_mcast)
+                   vlib_frame_t * frame,
+                   int do_counters, int is_midchain, int is_mcast)
 {
   ip_lookup_main_t *lm = &ip4_main.lookup_main;
   u32 *from = vlib_frame_vector_args (frame);
@@ -2292,7 +2330,7 @@ ip4_rewrite_inline (vlib_main_t * vm,
 
   n_left_from = frame->n_vectors;
   next_index = node->cached_next_index;
-  u32 cpu_index = os_get_cpu_number ();
+  u32 thread_index = vlib_get_thread_index ();
 
   while (n_left_from > 0)
     {
@@ -2335,8 +2373,16 @@ ip4_rewrite_inline (vlib_main_t * vm,
          adj_index0 = vnet_buffer (p0)->ip.adj_index[VLIB_TX];
          adj_index1 = vnet_buffer (p1)->ip.adj_index[VLIB_TX];
 
-         /* We should never rewrite a pkt using the MISS adjacency */
-         ASSERT (adj_index0 && adj_index1);
+         /*
+          * pre-fetch the per-adjacency counters
+          */
+         if (do_counters)
+           {
+             vlib_prefetch_combined_counter (&adjacency_counters,
+                                             thread_index, adj_index0);
+             vlib_prefetch_combined_counter (&adjacency_counters,
+                                             thread_index, adj_index1);
+           }
 
          ip0 = vlib_buffer_get_current (p0);
          ip1 = vlib_buffer_get_current (p1);
@@ -2440,14 +2486,6 @@ ip4_rewrite_inline (vlib_main_t * vm,
             rewrite_header.max_l3_packet_bytes ? IP4_ERROR_MTU_EXCEEDED :
             error1);
 
-         /*
-          * pre-fetch the per-adjacency counters
-          */
-         vlib_prefetch_combined_counter (&adjacency_counters,
-                                         cpu_index, adj_index0);
-         vlib_prefetch_combined_counter (&adjacency_counters,
-                                         cpu_index, adj_index1);
-
          /* Don't adjust the buffer for ttl issue; icmp-error node wants
           * to see the IP headerr */
          if (PREDICT_TRUE (error0 == IP4_ERROR_NONE))
@@ -2458,8 +2496,10 @@ ip4_rewrite_inline (vlib_main_t * vm,
              tx_sw_if_index0 = adj0[0].rewrite_header.sw_if_index;
              vnet_buffer (p0)->sw_if_index[VLIB_TX] = tx_sw_if_index0;
 
-             vnet_feature_arc_start (lm->output_feature_arc_index,
-                                     tx_sw_if_index0, &next0, p0);
+             if (PREDICT_FALSE
+                 (adj0[0].rewrite_header.flags & VNET_REWRITE_HAS_FEATURES))
+               vnet_feature_arc_start (lm->output_feature_arc_index,
+                                       tx_sw_if_index0, &next0, p0);
            }
          if (PREDICT_TRUE (error1 == IP4_ERROR_NONE))
            {
@@ -2470,8 +2510,10 @@ ip4_rewrite_inline (vlib_main_t * vm,
              tx_sw_if_index1 = adj1[0].rewrite_header.sw_if_index;
              vnet_buffer (p1)->sw_if_index[VLIB_TX] = tx_sw_if_index1;
 
-             vnet_feature_arc_start (lm->output_feature_arc_index,
-                                     tx_sw_if_index1, &next1, p1);
+             if (PREDICT_FALSE
+                 (adj1[0].rewrite_header.flags & VNET_REWRITE_HAS_FEATURES))
+               vnet_feature_arc_start (lm->output_feature_arc_index,
+                                       tx_sw_if_index1, &next1, p1);
            }
 
          /* Guess we are only writing on simple Ethernet header. */
@@ -2481,15 +2523,20 @@ ip4_rewrite_inline (vlib_main_t * vm,
          /*
           * Bump the per-adjacency counters
           */
-         vlib_increment_combined_counter
-           (&adjacency_counters,
-            cpu_index,
-            adj_index0, 1, vlib_buffer_length_in_chain (vm, p0) + rw_len0);
-
-         vlib_increment_combined_counter
-           (&adjacency_counters,
-            cpu_index,
-            adj_index1, 1, vlib_buffer_length_in_chain (vm, p1) + rw_len1);
+         if (do_counters)
+           {
+             vlib_increment_combined_counter
+               (&adjacency_counters,
+                thread_index,
+                adj_index0, 1,
+                vlib_buffer_length_in_chain (vm, p0) + rw_len0);
+
+             vlib_increment_combined_counter
+               (&adjacency_counters,
+                thread_index,
+                adj_index1, 1,
+                vlib_buffer_length_in_chain (vm, p1) + rw_len1);
+           }
 
          if (is_midchain)
            {
@@ -2501,8 +2548,8 @@ ip4_rewrite_inline (vlib_main_t * vm,
              /*
               * copy bytes from the IP address into the MAC rewrite
               */
-             vnet_fixup_one_header (adj0[0], &ip0->dst_address, ip0, 1);
-             vnet_fixup_one_header (adj1[0], &ip1->dst_address, ip1, 1);
+             vnet_fixup_one_header (adj0[0], &ip0->dst_address, ip0);
+             vnet_fixup_one_header (adj1[0], &ip1->dst_address, ip1);
            }
 
          vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
@@ -2524,9 +2571,6 @@ ip4_rewrite_inline (vlib_main_t * vm,
 
          adj_index0 = vnet_buffer (p0)->ip.adj_index[VLIB_TX];
 
-         /* We should never rewrite a pkt using the MISS adjacency */
-         ASSERT (adj_index0);
-
          adj0 = ip_get_adjacency (lm, adj_index0);
 
          ip0 = vlib_buffer_get_current (p0);
@@ -2572,8 +2616,9 @@ ip4_rewrite_inline (vlib_main_t * vm,
              p0->flags &= ~VNET_BUFFER_LOCALLY_ORIGINATED;
            }
 
-         vlib_prefetch_combined_counter (&adjacency_counters,
-                                         cpu_index, adj_index0);
+         if (do_counters)
+           vlib_prefetch_combined_counter (&adjacency_counters,
+                                           thread_index, adj_index0);
 
          /* Guess we are only writing on simple Ethernet header. */
          vnet_rewrite_one_header (adj0[0], ip0, sizeof (ethernet_header_t));
@@ -2582,17 +2627,18 @@ ip4_rewrite_inline (vlib_main_t * vm,
              /*
               * copy bytes from the IP address into the MAC rewrite
               */
-             vnet_fixup_one_header (adj0[0], &ip0->dst_address, ip0, 1);
+             vnet_fixup_one_header (adj0[0], &ip0->dst_address, ip0);
            }
 
          /* Update packet buffer attributes/set output interface. */
          rw_len0 = adj0[0].rewrite_header.data_bytes;
          vnet_buffer (p0)->ip.save_rewrite_length = rw_len0;
 
-         vlib_increment_combined_counter
-           (&adjacency_counters,
-            cpu_index,
-            adj_index0, 1, vlib_buffer_length_in_chain (vm, p0) + rw_len0);
+         if (do_counters)
+           vlib_increment_combined_counter
+             (&adjacency_counters,
+              thread_index, adj_index0, 1,
+              vlib_buffer_length_in_chain (vm, p0) + rw_len0);
 
          /* Check MTU of outgoing interface. */
          error0 = (vlib_buffer_length_in_chain (vm, p0)
@@ -2617,8 +2663,10 @@ ip4_rewrite_inline (vlib_main_t * vm,
                  adj0->sub_type.midchain.fixup_func (vm, adj0, p0);
                }
 
-             vnet_feature_arc_start (lm->output_feature_arc_index,
-                                     tx_sw_if_index0, &next0, p0);
+             if (PREDICT_FALSE
+                 (adj0[0].rewrite_header.flags & VNET_REWRITE_HAS_FEATURES))
+               vnet_feature_arc_start (lm->output_feature_arc_index,
+                                       tx_sw_if_index0, &next0, p0);
 
            }
 
@@ -2678,21 +2726,40 @@ static uword
 ip4_rewrite (vlib_main_t * vm,
             vlib_node_runtime_t * node, vlib_frame_t * frame)
 {
-  return ip4_rewrite_inline (vm, node, frame, 0, 0);
+  if (adj_are_counters_enabled ())
+    return ip4_rewrite_inline (vm, node, frame, 1, 0, 0);
+  else
+    return ip4_rewrite_inline (vm, node, frame, 0, 0, 0);
 }
 
 static uword
 ip4_midchain (vlib_main_t * vm,
              vlib_node_runtime_t * node, vlib_frame_t * frame)
 {
-  return ip4_rewrite_inline (vm, node, frame, 1, 0);
+  if (adj_are_counters_enabled ())
+    return ip4_rewrite_inline (vm, node, frame, 1, 1, 0);
+  else
+    return ip4_rewrite_inline (vm, node, frame, 0, 1, 0);
 }
 
 static uword
 ip4_rewrite_mcast (vlib_main_t * vm,
                   vlib_node_runtime_t * node, vlib_frame_t * frame)
 {
-  return ip4_rewrite_inline (vm, node, frame, 0, 1);
+  if (adj_are_counters_enabled ())
+    return ip4_rewrite_inline (vm, node, frame, 1, 0, 1);
+  else
+    return ip4_rewrite_inline (vm, node, frame, 0, 0, 1);
+}
+
+static uword
+ip4_mcast_midchain (vlib_main_t * vm,
+                   vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+  if (adj_are_counters_enabled ())
+    return ip4_rewrite_inline (vm, node, frame, 1, 1, 1);
+  else
+    return ip4_rewrite_inline (vm, node, frame, 0, 1, 1);
 }
 
 /* *INDENT-OFF* */
@@ -2721,6 +2788,16 @@ VLIB_REGISTER_NODE (ip4_rewrite_mcast_node) = {
 };
 VLIB_NODE_FUNCTION_MULTIARCH (ip4_rewrite_mcast_node, ip4_rewrite_mcast)
 
+VLIB_REGISTER_NODE (ip4_mcast_midchain_node, static) = {
+  .function = ip4_mcast_midchain,
+  .name = "ip4-mcast-midchain",
+  .vector_size = sizeof (u32),
+
+  .format_trace = format_ip4_rewrite_trace,
+  .sibling_of = "ip4-rewrite",
+};
+VLIB_NODE_FUNCTION_MULTIARCH (ip4_mcast_midchain_node, ip4_mcast_midchain)
+
 VLIB_REGISTER_NODE (ip4_midchain_node) = {
   .function = ip4_midchain,
   .name = "ip4-midchain",
@@ -2736,6 +2813,7 @@ add_del_interface_table (vlib_main_t * vm,
                         unformat_input_t * input, vlib_cli_command_t * cmd)
 {
   vnet_main_t *vnm = vnet_get_main ();
+  ip_interface_address_t *ia;
   clib_error_t *error = 0;
   u32 sw_if_index, table_id;
 
@@ -2757,29 +2835,44 @@ add_del_interface_table (vlib_main_t * vm,
       goto done;
     }
 
-  {
-    ip4_main_t *im = &ip4_main;
-    u32 fib_index;
-
-    fib_index = fib_table_find_or_create_and_lock (FIB_PROTOCOL_IP4,
-                                                  table_id);
-
-    //
-    // FIXME-LATER
-    //  changing an interface's table has consequences for any connecteds
-    //  and adj-fibs already installed.
-    //
-    vec_validate (im->fib_index_by_sw_if_index, sw_if_index);
-    im->fib_index_by_sw_if_index[sw_if_index] = fib_index;
-
-    fib_index = mfib_table_find_or_create_and_lock (FIB_PROTOCOL_IP4,
-                                                   table_id);
-    vec_validate (im->mfib_index_by_sw_if_index, sw_if_index);
-    im->mfib_index_by_sw_if_index[sw_if_index] = fib_index;
-  }
+  /*
+   * If the interface already has in IP address, then a change int
+   * VRF is not allowed. The IP address applied must first be removed.
+   * We do not do that automatically here, since VPP has no knowledge
+   * of whether thoses subnets are valid in the destination VRF.
+   */
+  /* *INDENT-OFF* */
+  foreach_ip_interface_address (&ip4_main.lookup_main,
+                                ia, sw_if_index,
+                                1 /* honor unnumbered */,
+  ({
+      ip4_address_t * a;
+
+      a = ip_interface_address_get_address (&ip4_main.lookup_main, ia);
+      error = clib_error_return (0, "interface %U has address %U",
+                                 format_vnet_sw_if_index_name, vnm,
+                                 sw_if_index,
+                                 format_ip4_address, a);
+      goto done;
+   }));
+   /* *INDENT-ON* */
+
+{
+  ip4_main_t *im = &ip4_main;
+  u32 fib_index;
+
+  fib_index = fib_table_find_or_create_and_lock (FIB_PROTOCOL_IP4, table_id);
+
+  vec_validate (im->fib_index_by_sw_if_index, sw_if_index);
+  im->fib_index_by_sw_if_index[sw_if_index] = fib_index;
+
+  fib_index = mfib_table_find_or_create_and_lock (FIB_PROTOCOL_IP4, table_id);
+  vec_validate (im->mfib_index_by_sw_if_index, sw_if_index);
+  im->mfib_index_by_sw_if_index[sw_if_index] = fib_index;
+}
 
 done:
-  return error;
+return error;
 }
 
 /*?
@@ -2790,13 +2883,12 @@ done:
  * an IP Address is assigned to an interface in the table (which adds a route
  * automatically).
  *
- * @note IP addresses added after setting the interface IP table end up in
- * the indicated FIB table. If the IP address is added prior to adding the
- * interface to the FIB table, it will NOT be part of the FIB table. Predictable
- * but potentially counter-intuitive results occur if you provision interface
- * addresses in multiple FIBs. Upon RX, packets will be processed in the last
- * IP table ID provisioned. It might be marginally useful to evade source RPF
- * drops to put an interface address into multiple FIBs.
+ * @note IP addresses added after setting the interface IP table are added to
+ * the indicated FIB table. If an IP address is added prior to changing the
+ * table then this is an error. The control plane must remove these addresses
+ * first and then change the table. VPP will not automatically move the
+ * addresses from the old to the new table as it does not know the validity
+ * of such a change.
  *
  * @cliexpar
  * Example of how to add an interface to an IPv4 FIB table (where 2 is the table-id):
@@ -2820,15 +2912,10 @@ ip4_lookup_validate (ip4_address_t * a, u32 fib_index0)
 
   mtrie0 = &ip4_fib_get (fib_index0)->mtrie;
 
-  leaf0 = IP4_FIB_MTRIE_LEAF_ROOT;
-  leaf0 = ip4_fib_mtrie_lookup_step (mtrie0, leaf0, a, 0);
-  leaf0 = ip4_fib_mtrie_lookup_step (mtrie0, leaf0, a, 1);
+  leaf0 = ip4_fib_mtrie_lookup_step_one (mtrie0, a);
   leaf0 = ip4_fib_mtrie_lookup_step (mtrie0, leaf0, a, 2);
   leaf0 = ip4_fib_mtrie_lookup_step (mtrie0, leaf0, a, 3);
 
-  /* Handle default route. */
-  leaf0 = (leaf0 == IP4_FIB_MTRIE_LEAF_EMPTY ? mtrie0->default_leaf : leaf0);
-
   lbi0 = ip4_fib_mtrie_leaf_get_adj_index (leaf0);
 
   return lbi0 == ip4_fib_table_lookup_lb (ip4_fib_get (fib_index0), a);