ip: Protocol Independent IP Neighbors

Type: feature

 - ip-neighbour: generic neighbour handling; APIs, DBs, event handling,
aging
 - arp: ARP protocol implementation
 - ip6-nd; IPv6 neighbor discovery implementation; separate ND,
MLD, RA
 - ip6-link; manage link-local addresses
 - l2-arp-term; events separated from IP neighbours, since they are not
the same.

vnet retains just enough education to perform ND/ARP packet
construction.
arp and ip6-nd to be moved to plugins soon.

Change-Id: I88dedd0006b299344f4c7024a0aa5baa6b9a8bbe
Signed-off-by: Neale Ranns <nranns@cisco.com>

8 files changed, 212 insertions, 3208 deletions

diff --git a/src/vnet/ethernet/arp.c b/src/vnet/ethernet/arp.c
deleted file mode 100644
index 6b1069ecb6d..00000000000
--- a/src/vnet/ethernet/arp.c
+++ /dev/null
@@ -1,3062 +0,0 @@
-/*
- * ethernet/arp.c: IP v4 ARP node
- *
- * Copyright (c) 2010 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.
- */
-
-#include <vnet/ip/ip.h>
-#include <vnet/ip/ip_neighbor.h>
-#include <vnet/ip/ip6.h>
-#include <vnet/ethernet/ethernet.h>
-#include <vnet/ethernet/arp.h>
-#include <vnet/l2/l2_input.h>
-#include <vppinfra/mhash.h>
-#include <vnet/fib/ip4_fib.h>
-#include <vnet/fib/fib_entry_src.h>
-#include <vnet/adj/adj_nbr.h>
-#include <vnet/adj/adj_mcast.h>
-#include <vnet/mpls/mpls.h>
-#include <vnet/l2/feat_bitmap.h>
-
-#include <vlibmemory/api.h>
-
-/**
- * @file
- * @brief IPv4 ARP.
- *
- * This file contains code to manage the IPv4 ARP tables (IP Address
- * to MAC Address lookup).
- */
-
-
-/**
- * @brief Per-interface ARP configuration and state
- */
-typedef struct ethernet_arp_interface_t_
-{
-  /**
-   * Hash table of ARP entries.
-   * Since this hash table is per-interface, the key is only the IPv4 address.
-   */
-  uword *arp_entries;
-  /**
-   * Is ARP enabled on this interface
-   */
-  u32 enabled;
-  /**
-   * Is Proxy ARP enabled on this interface
-   */
-  u32 proxy_enabled;
-} ethernet_arp_interface_t;
-
-typedef struct
-{
-  ip4_address_t lo_addr;
-  ip4_address_t hi_addr;
-  u32 fib_index;
-} ethernet_proxy_arp_t;
-
-typedef struct
-{
-  u32 next_index;
-  uword node_index;
-  uword type_opaque;
-  uword data;
-  /* Used for arp event notification only */
-  arp_change_event_cb_t data_callback;
-  u32 pid;
-} pending_resolution_t;
-
-typedef struct
-{
-  /* Hash tables mapping name to opcode. */
-  uword *opcode_by_name;
-
-  /* lite beer "glean" adjacency handling */
-  uword *pending_resolutions_by_address;
-  pending_resolution_t *pending_resolutions;
-
-  /* Mac address change notification */
-  uword *mac_changes_by_address;
-  pending_resolution_t *mac_changes;
-
-  ethernet_arp_ip4_entry_t *ip4_entry_pool;
-
-  /* ARP attack mitigation */
-  u32 arp_delete_rotor;
-  u32 limit_arp_cache_size;
-
-  /** Per interface state */
-  ethernet_arp_interface_t *ethernet_arp_by_sw_if_index;
-
-  /* Proxy arp vector */
-  ethernet_proxy_arp_t *proxy_arps;
-
-  uword wc_ip4_arp_publisher_node;
-  uword wc_ip4_arp_publisher_et;
-
-  /* ARP feature arc index */
-  u8 feature_arc_index;
-} ethernet_arp_main_t;
-
-static ethernet_arp_main_t ethernet_arp_main;
-
-typedef struct
-{
-  u32 sw_if_index;
-  ip4_address_t ip4;
-  mac_address_t mac;
-  ip_neighbor_flags_t nbr_flags;
-  u32 flags;
-#define ETHERNET_ARP_ARGS_REMOVE (1<<0)
-#define ETHERNET_ARP_ARGS_FLUSH  (1<<1)
-#define ETHERNET_ARP_ARGS_POPULATE  (1<<2)
-#define ETHERNET_ARP_ARGS_WC_PUB  (1<<3)
-} vnet_arp_set_ip4_over_ethernet_rpc_args_t;
-
-static const u8 vrrp_prefix[] = { 0x00, 0x00, 0x5E, 0x00, 0x01 };
-
-/* Node index for send_garp_na_process */
-u32 send_garp_na_process_node_index;
-
-static void
-set_ip4_over_ethernet_rpc_callback (vnet_arp_set_ip4_over_ethernet_rpc_args_t
-				    * a);
-
-static u8 *
-format_ethernet_arp_hardware_type (u8 * s, va_list * va)
-{
-  ethernet_arp_hardware_type_t h = va_arg (*va, ethernet_arp_hardware_type_t);
-  char *t = 0;
-  switch (h)
-    {
-#define _(n,f) case n: t = #f; break;
-      foreach_ethernet_arp_hardware_type;
-#undef _
-
-    default:
-      return format (s, "unknown 0x%x", h);
-    }
-
-  return format (s, "%s", t);
-}
-
-static u8 *
-format_ethernet_arp_opcode (u8 * s, va_list * va)
-{
-  ethernet_arp_opcode_t o = va_arg (*va, ethernet_arp_opcode_t);
-  char *t = 0;
-  switch (o)
-    {
-#define _(f) case ETHERNET_ARP_OPCODE_##f: t = #f; break;
-      foreach_ethernet_arp_opcode;
-#undef _
-
-    default:
-      return format (s, "unknown 0x%x", o);
-    }
-
-  return format (s, "%s", t);
-}
-
-static uword
-unformat_ethernet_arp_opcode_host_byte_order (unformat_input_t * input,
-					      va_list * args)
-{
-  int *result = va_arg (*args, int *);
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-  int x, i;
-
-  /* Numeric opcode. */
-  if (unformat (input, "0x%x", &x) || unformat (input, "%d", &x))
-    {
-      if (x >= (1 << 16))
-	return 0;
-      *result = x;
-      return 1;
-    }
-
-  /* Named type. */
-  if (unformat_user (input, unformat_vlib_number_by_name,
-		     am->opcode_by_name, &i))
-    {
-      *result = i;
-      return 1;
-    }
-
-  return 0;
-}
-
-static uword
-unformat_ethernet_arp_opcode_net_byte_order (unformat_input_t * input,
-					     va_list * args)
-{
-  int *result = va_arg (*args, int *);
-  if (!unformat_user
-      (input, unformat_ethernet_arp_opcode_host_byte_order, result))
-    return 0;
-
-  *result = clib_host_to_net_u16 ((u16) * result);
-  return 1;
-}
-
-static u8 *
-format_ethernet_arp_header (u8 * s, va_list * va)
-{
-  ethernet_arp_header_t *a = va_arg (*va, ethernet_arp_header_t *);
-  u32 max_header_bytes = va_arg (*va, u32);
-  u32 indent;
-  u16 l2_type, l3_type;
-
-  if (max_header_bytes != 0 && sizeof (a[0]) > max_header_bytes)
-    return format (s, "ARP header truncated");
-
-  l2_type = clib_net_to_host_u16 (a->l2_type);
-  l3_type = clib_net_to_host_u16 (a->l3_type);
-
-  indent = format_get_indent (s);
-
-  s = format (s, "%U, type %U/%U, address size %d/%d",
-	      format_ethernet_arp_opcode, clib_net_to_host_u16 (a->opcode),
-	      format_ethernet_arp_hardware_type, l2_type,
-	      format_ethernet_type, l3_type,
-	      a->n_l2_address_bytes, a->n_l3_address_bytes);
-
-  if (l2_type == ETHERNET_ARP_HARDWARE_TYPE_ethernet
-      && l3_type == ETHERNET_TYPE_IP4)
-    {
-      s = format (s, "\n%U%U/%U -> %U/%U",
-		  format_white_space, indent,
-		  format_mac_address_t, &a->ip4_over_ethernet[0].mac,
-		  format_ip4_address, &a->ip4_over_ethernet[0].ip4,
-		  format_mac_address_t, &a->ip4_over_ethernet[1].mac,
-		  format_ip4_address, &a->ip4_over_ethernet[1].ip4);
-    }
-  else
-    {
-      uword n2 = a->n_l2_address_bytes;
-      uword n3 = a->n_l3_address_bytes;
-      s = format (s, "\n%U%U/%U -> %U/%U",
-		  format_white_space, indent,
-		  format_hex_bytes, a->data + 0 * n2 + 0 * n3, n2,
-		  format_hex_bytes, a->data + 1 * n2 + 0 * n3, n3,
-		  format_hex_bytes, a->data + 1 * n2 + 1 * n3, n2,
-		  format_hex_bytes, a->data + 2 * n2 + 1 * n3, n3);
-    }
-
-  return s;
-}
-
-u8 *
-format_ethernet_arp_ip4_entry (u8 * s, va_list * va)
-{
-  vnet_main_t *vnm = va_arg (*va, vnet_main_t *);
-  ethernet_arp_ip4_entry_t *e = va_arg (*va, ethernet_arp_ip4_entry_t *);
-  vnet_sw_interface_t *si;
-
-  if (!e)
-    return format (s, "%=12s%=16s%=6s%=20s%=24s", "Time", "IP4",
-		   "Flags", "Ethernet", "Interface");
-
-  si = vnet_get_sw_interface (vnm, e->sw_if_index);
-
-  return format (s, "%=12U%=16U%=6U%=20U%U",
-		 format_vlib_time, vnm->vlib_main, e->time_last_updated,
-		 format_ip4_address, &e->ip4_address,
-		 format_ip_neighbor_flags, e->flags,
-		 format_mac_address_t, &e->mac,
-		 format_vnet_sw_interface_name, vnm, si);
-}
-
-typedef struct
-{
-  u8 packet_data[64];
-} ethernet_arp_input_trace_t;
-
-static u8 *
-format_ethernet_arp_input_trace (u8 * s, va_list * va)
-{
-  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*va, vlib_main_t *);
-  CLIB_UNUSED (vlib_node_t * node) = va_arg (*va, vlib_node_t *);
-  ethernet_arp_input_trace_t *t = va_arg (*va, ethernet_arp_input_trace_t *);
-
-  s = format (s, "%U",
-	      format_ethernet_arp_header,
-	      t->packet_data, sizeof (t->packet_data));
-
-  return s;
-}
-
-static u8 *
-format_arp_term_input_trace (u8 * s, va_list * va)
-{
-  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*va, vlib_main_t *);
-  CLIB_UNUSED (vlib_node_t * node) = va_arg (*va, vlib_node_t *);
-  ethernet_arp_input_trace_t *t = va_arg (*va, ethernet_arp_input_trace_t *);
-
-  /* arp-term trace data saved is either arp or ip6/icmp6 packet:
-     - for arp, the 1st 16-bit field is hw type of value of 0x0001.
-     - for ip6, the first nibble has value of 6. */
-  s = format (s, "%U", t->packet_data[0] == 0 ?
-	      format_ethernet_arp_header : format_ip6_header,
-	      t->packet_data, sizeof (t->packet_data));
-
-  return s;
-}
-
-static void
-arp_nbr_probe (ip_adjacency_t * adj)
-{
-  vnet_main_t *vnm = vnet_get_main ();
-  ip4_main_t *im = &ip4_main;
-  ip_interface_address_t *ia;
-  ethernet_arp_header_t *h;
-  vnet_hw_interface_t *hi;
-  vnet_sw_interface_t *si;
-  ip4_address_t *src;
-  vlib_buffer_t *b;
-  vlib_main_t *vm;
-  u32 bi = 0;
-
-  vm = vlib_get_main ();
-
-  si = vnet_get_sw_interface (vnm, adj->rewrite_header.sw_if_index);
-
-  if (!(si->flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP))
-    {
-      return;
-    }
-
-  src =
-    ip4_interface_address_matching_destination (im,
-						&adj->sub_type.nbr.next_hop.
-						ip4,
-						adj->rewrite_header.
-						sw_if_index, &ia);
-  if (!src)
-    {
-      return;
-    }
-
-  h =
-    vlib_packet_template_get_packet (vm, &im->ip4_arp_request_packet_template,
-				     &bi);
-  if (!h)
-    return;
-
-  hi = vnet_get_sup_hw_interface (vnm, adj->rewrite_header.sw_if_index);
-
-  mac_address_from_bytes (&h->ip4_over_ethernet[0].mac, hi->hw_address);
-
-  h->ip4_over_ethernet[0].ip4 = src[0];
-  h->ip4_over_ethernet[1].ip4 = adj->sub_type.nbr.next_hop.ip4;
-
-  b = vlib_get_buffer (vm, bi);
-  vnet_buffer (b)->sw_if_index[VLIB_RX] =
-    vnet_buffer (b)->sw_if_index[VLIB_TX] = adj->rewrite_header.sw_if_index;
-
-  /* Add encapsulation string for software interface (e.g. ethernet header). */
-  vnet_rewrite_one_header (adj[0], h, sizeof (ethernet_header_t));
-  vlib_buffer_advance (b, -adj->rewrite_header.data_bytes);
-
-  {
-    vlib_frame_t *f = vlib_get_frame_to_node (vm, hi->output_node_index);
-    u32 *to_next = vlib_frame_vector_args (f);
-    to_next[0] = bi;
-    f->n_vectors = 1;
-    vlib_put_frame_to_node (vm, hi->output_node_index, f);
-  }
-}
-
-static void
-arp_mk_complete (adj_index_t ai, ethernet_arp_ip4_entry_t * e)
-{
-  adj_nbr_update_rewrite
-    (ai, ADJ_NBR_REWRITE_FLAG_COMPLETE,
-     ethernet_build_rewrite (vnet_get_main (),
-			     e->sw_if_index,
-			     adj_get_link_type (ai), &e->mac));
-}
-
-static void
-arp_mk_incomplete (adj_index_t ai)
-{
-  ip_adjacency_t *adj = adj_get (ai);
-
-  adj_nbr_update_rewrite
-    (ai,
-     ADJ_NBR_REWRITE_FLAG_INCOMPLETE,
-     ethernet_build_rewrite (vnet_get_main (),
-			     adj->rewrite_header.sw_if_index,
-			     VNET_LINK_ARP,
-			     VNET_REWRITE_FOR_SW_INTERFACE_ADDRESS_BROADCAST));
-}
-
-static ethernet_arp_ip4_entry_t *
-arp_entry_find (ethernet_arp_interface_t * eai, const ip4_address_t * addr)
-{
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-  ethernet_arp_ip4_entry_t *e = NULL;
-  uword *p;
-
-  if (NULL != eai->arp_entries)
-    {
-      p = hash_get (eai->arp_entries, addr->as_u32);
-      if (!p)
-	return (NULL);
-
-      e = pool_elt_at_index (am->ip4_entry_pool, p[0]);
-    }
-
-  return (e);
-}
-
-static adj_walk_rc_t
-arp_mk_complete_walk (adj_index_t ai, void *ctx)
-{
-  ethernet_arp_ip4_entry_t *e = ctx;
-
-  arp_mk_complete (ai, e);
-
-  return (ADJ_WALK_RC_CONTINUE);
-}
-
-static adj_walk_rc_t
-arp_mk_incomplete_walk (adj_index_t ai, void *ctx)
-{
-  arp_mk_incomplete (ai);
-
-  return (ADJ_WALK_RC_CONTINUE);
-}
-
-static int
-arp_is_enabled (ethernet_arp_main_t * am, u32 sw_if_index)
-{
-  if (vec_len (am->ethernet_arp_by_sw_if_index) <= sw_if_index)
-    return 0;
-
-  return (am->ethernet_arp_by_sw_if_index[sw_if_index].enabled);
-}
-
-static void
-arp_enable (ethernet_arp_main_t * am, u32 sw_if_index)
-{
-  if (arp_is_enabled (am, sw_if_index))
-    return;
-
-  vec_validate (am->ethernet_arp_by_sw_if_index, sw_if_index);
-
-  am->ethernet_arp_by_sw_if_index[sw_if_index].enabled = 1;
-
-  vnet_feature_enable_disable ("arp", "arp-reply", sw_if_index, 1, NULL, 0);
-  vnet_feature_enable_disable ("arp", "arp-disabled", sw_if_index, 0, NULL,
-			       0);
-}
-
-static int
-vnet_arp_flush_ip4_over_ethernet_internal (vnet_main_t * vnm,
-					   vnet_arp_set_ip4_over_ethernet_rpc_args_t
-					   * args);
-
-static void
-arp_disable (ethernet_arp_main_t * am, u32 sw_if_index)
-{
-  ethernet_arp_interface_t *eai;
-  ethernet_arp_ip4_entry_t *e;
-  u32 i, *to_delete = 0;
-  hash_pair_t *pair;
-
-  if (!arp_is_enabled (am, sw_if_index))
-    return;
-
-  vnet_feature_enable_disable ("arp", "arp-disabled", sw_if_index, 1, NULL,
-			       0);
-  vnet_feature_enable_disable ("arp", "arp-reply", sw_if_index, 0, NULL, 0);
-
-  eai = &am->ethernet_arp_by_sw_if_index[sw_if_index];
-
-
-  /* *INDENT-OFF* */
-  hash_foreach_pair (pair, eai->arp_entries,
-  ({
-    e = pool_elt_at_index(am->ip4_entry_pool,
-                          pair->value[0]);
-    vec_add1 (to_delete, e - am->ip4_entry_pool);
-  }));
-  /* *INDENT-ON* */
-
-  for (i = 0; i < vec_len (to_delete); i++)
-    {
-      e = pool_elt_at_index (am->ip4_entry_pool, to_delete[i]);
-
-      vnet_arp_set_ip4_over_ethernet_rpc_args_t delme = {
-	.ip4.as_u32 = e->ip4_address.as_u32,
-	.sw_if_index = e->sw_if_index,
-	.flags = ETHERNET_ARP_ARGS_FLUSH,
-      };
-      mac_address_copy (&delme.mac, &e->mac);
-
-      vnet_arp_flush_ip4_over_ethernet_internal (vnet_get_main (), &delme);
-    }
-
-  vec_free (to_delete);
-
-  eai->enabled = 0;
-}
-
-void
-arp_update_adjacency (vnet_main_t * vnm, u32 sw_if_index, u32 ai)
-{
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-  ethernet_arp_interface_t *arp_int;
-  ethernet_arp_ip4_entry_t *e;
-  ip_adjacency_t *adj;
-
-  adj = adj_get (ai);
-
-  arp_enable (am, sw_if_index);
-  arp_int = &am->ethernet_arp_by_sw_if_index[sw_if_index];
-  e = arp_entry_find (arp_int, &adj->sub_type.nbr.next_hop.ip4);
-
-  switch (adj->lookup_next_index)
-    {
-    case IP_LOOKUP_NEXT_GLEAN:
-      adj_glean_update_rewrite (ai);
-      break;
-    case IP_LOOKUP_NEXT_ARP:
-      if (NULL != e)
-	{
-	  adj_nbr_walk_nh4 (sw_if_index,
-			    &e->ip4_address, arp_mk_complete_walk, e);
-	}
-      else
-	{
-	  /*
-	   * no matching ARP entry.
-	   * construct the rewrite required to for an ARP packet, and stick
-	   * that in the adj's pipe to smoke.
-	   */
-	  adj_nbr_update_rewrite
-	    (ai,
-	     ADJ_NBR_REWRITE_FLAG_INCOMPLETE,
-	     ethernet_build_rewrite
-	     (vnm,
-	      sw_if_index,
-	      VNET_LINK_ARP,
-	      VNET_REWRITE_FOR_SW_INTERFACE_ADDRESS_BROADCAST));
-
-	  /*
-	   * since the FIB has added this adj for a route, it makes sense it
-	   * may want to forward traffic sometime soon. Let's send a
-	   * speculative ARP. just one. If we were to do periodically that
-	   * wouldn't be bad either, but that's more code than i'm prepared to
-	   * write at this time for relatively little reward.
-	   */
-	  arp_nbr_probe (adj);
-	}
-      break;
-    case IP_LOOKUP_NEXT_BCAST:
-      adj_nbr_update_rewrite (ai,
-			      ADJ_NBR_REWRITE_FLAG_COMPLETE,
-			      ethernet_build_rewrite
-			      (vnm,
-			       sw_if_index,
-			       VNET_LINK_IP4,
-			       VNET_REWRITE_FOR_SW_INTERFACE_ADDRESS_BROADCAST));
-      break;
-    case IP_LOOKUP_NEXT_MCAST:
-      {
-	/*
-	 * Construct a partial rewrite from the known ethernet mcast dest MAC
-	 */
-	u8 *rewrite;
-	u8 offset;
-
-	rewrite = ethernet_build_rewrite (vnm,
-					  sw_if_index,
-					  adj->ia_link,
-					  ethernet_ip4_mcast_dst_addr ());
-	offset = vec_len (rewrite) - 2;
-
-	/*
-	 * Complete the remaining fields of the adj's rewrite to direct the
-	 * complete of the rewrite at switch time by copying in the IP
-	 * dst address's bytes.
-	 * Offset is 2 bytes into the MAC destination address.
-	 */
-	adj_mcast_update_rewrite (ai, rewrite, offset);
-
-	break;
-      }
-    case IP_LOOKUP_NEXT_DROP:
-    case IP_LOOKUP_NEXT_PUNT:
-    case IP_LOOKUP_NEXT_LOCAL:
-    case IP_LOOKUP_NEXT_REWRITE:
-    case IP_LOOKUP_NEXT_MCAST_MIDCHAIN:
-    case IP_LOOKUP_NEXT_MIDCHAIN:
-    case IP_LOOKUP_NEXT_ICMP_ERROR:
-    case IP_LOOKUP_N_NEXT:
-      ASSERT (0);
-      break;
-    }
-}
-
-static void
-arp_adj_fib_add (ethernet_arp_ip4_entry_t * e, u32 fib_index)
-{
-  fib_prefix_t pfx = {
-    .fp_len = 32,
-    .fp_proto = FIB_PROTOCOL_IP4,
-    .fp_addr.ip4 = e->ip4_address,
-  };
-
-  e->fib_entry_index =
-    fib_table_entry_path_add (fib_index, &pfx, FIB_SOURCE_ADJ,
-			      FIB_ENTRY_FLAG_ATTACHED,
-			      DPO_PROTO_IP4, &pfx.fp_addr,
-			      e->sw_if_index, ~0, 1, NULL,
-			      FIB_ROUTE_PATH_FLAG_NONE);
-  fib_table_lock (fib_index, FIB_PROTOCOL_IP4, FIB_SOURCE_ADJ);
-}
-
-static void
-arp_adj_fib_remove (ethernet_arp_ip4_entry_t * e, u32 fib_index)
-{
-  if (FIB_NODE_INDEX_INVALID != e->fib_entry_index)
-    {
-      fib_prefix_t pfx = {
-	.fp_len = 32,
-	.fp_proto = FIB_PROTOCOL_IP4,
-	.fp_addr.ip4 = e->ip4_address,
-      };
-      u32 fib_index;
-
-      fib_index = ip4_fib_table_get_index_for_sw_if_index (e->sw_if_index);
-
-      fib_table_entry_path_remove (fib_index, &pfx,
-				   FIB_SOURCE_ADJ,
-				   DPO_PROTO_IP4,
-				   &pfx.fp_addr,
-				   e->sw_if_index, ~0, 1,
-				   FIB_ROUTE_PATH_FLAG_NONE);
-      fib_table_unlock (fib_index, FIB_PROTOCOL_IP4, FIB_SOURCE_ADJ);
-    }
-}
-
-static ethernet_arp_ip4_entry_t *
-force_reuse_arp_entry (void)
-{
-  ethernet_arp_ip4_entry_t *e;
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-  u32 count = 0;
-  u32 index = pool_next_index (am->ip4_entry_pool, am->arp_delete_rotor);
-  if (index == ~0)		/* Try again from elt 0 */
-    index = pool_next_index (am->ip4_entry_pool, index);
-
-  /* Find a non-static random entry to free up for reuse */
-  do
-    {
-      if ((count++ == 100) || (index == ~0))
-	return NULL;		/* give up after 100 entries */
-      e = pool_elt_at_index (am->ip4_entry_pool, index);
-      am->arp_delete_rotor = index;
-      index = pool_next_index (am->ip4_entry_pool, index);
-    }
-  while (e->flags & IP_NEIGHBOR_FLAG_STATIC);
-
-  /* Remove ARP entry from its interface and update fib */
-  hash_unset
-    (am->ethernet_arp_by_sw_if_index[e->sw_if_index].arp_entries,
-     e->ip4_address.as_u32);
-  arp_adj_fib_remove
-    (e, ip4_fib_table_get_index_for_sw_if_index (e->sw_if_index));
-  adj_nbr_walk_nh4 (e->sw_if_index,
-		    &e->ip4_address, arp_mk_incomplete_walk, e);
-  return e;
-}
-
-static int
-vnet_arp_set_ip4_over_ethernet_internal (vnet_main_t * vnm,
-					 vnet_arp_set_ip4_over_ethernet_rpc_args_t
-					 * args)
-{
-  ethernet_arp_ip4_entry_t *e = 0;
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-  vlib_main_t *vm = vlib_get_main ();
-  int make_new_arp_cache_entry = 1;
-  uword *p;
-  pending_resolution_t *pr, *mc;
-  ethernet_arp_interface_t *arp_int;
-  u32 sw_if_index = args->sw_if_index;
-
-  arp_enable (am, sw_if_index);
-
-  arp_int = &am->ethernet_arp_by_sw_if_index[sw_if_index];
-
-  if (NULL != arp_int->arp_entries)
-    {
-      p = hash_get (arp_int->arp_entries, args->ip4.as_u32);
-      if (p)
-	{
-	  e = pool_elt_at_index (am->ip4_entry_pool, p[0]);
-
-	  /* Refuse to over-write static arp. */
-	  if (!(args->nbr_flags & IP_NEIGHBOR_FLAG_STATIC) &&
-	      (e->flags & IP_NEIGHBOR_FLAG_STATIC))
-	    {
-	      /* if MAC address match, still check to send event */
-	      if (mac_address_equal (&e->mac, &args->mac))
-		goto check_customers;
-	      return -2;
-	    }
-	  make_new_arp_cache_entry = 0;
-	}
-    }
-
-  if (make_new_arp_cache_entry)
-    {
-      if (am->limit_arp_cache_size &&
-	  pool_elts (am->ip4_entry_pool) >= am->limit_arp_cache_size)
-	{
-	  e = force_reuse_arp_entry ();
-	  if (NULL == e)
-	    return -2;
-	}
-      else
-	pool_get (am->ip4_entry_pool, e);
-
-      if (NULL == arp_int->arp_entries)
-	arp_int->arp_entries = hash_create (0, sizeof (u32));
-
-      hash_set (arp_int->arp_entries, args->ip4.as_u32,
-		e - am->ip4_entry_pool);
-
-      e->sw_if_index = sw_if_index;
-      e->ip4_address = args->ip4;
-      e->fib_entry_index = FIB_NODE_INDEX_INVALID;
-      mac_address_copy (&e->mac, &args->mac);
-
-      if (!(args->nbr_flags & IP_NEIGHBOR_FLAG_NO_FIB_ENTRY))
-	{
-	  arp_adj_fib_add (e,
-			   ip4_fib_table_get_index_for_sw_if_index
-			   (e->sw_if_index));
-	}
-      else
-	{
-	  e->flags |= IP_NEIGHBOR_FLAG_NO_FIB_ENTRY;
-	}
-    }
-  else
-    {
-      /*
-       * prevent a DoS attack from the data-plane that
-       * spams us with no-op updates to the MAC address
-       */
-      if (mac_address_equal (&e->mac, &args->mac))
-	{
-	  e->time_last_updated = vlib_time_now (vm);
-	  goto check_customers;
-	}
-
-      /* Update ethernet address. */
-      mac_address_copy (&e->mac, &args->mac);
-    }
-
-  /* Update time stamp and flags. */
-  e->time_last_updated = vlib_time_now (vm);
-  if (args->nbr_flags & IP_NEIGHBOR_FLAG_STATIC)
-    {
-      e->flags &= ~IP_NEIGHBOR_FLAG_DYNAMIC;
-      e->flags |= IP_NEIGHBOR_FLAG_STATIC;
-    }
-  else
-    {
-      e->flags &= ~IP_NEIGHBOR_FLAG_STATIC;
-      e->flags |= IP_NEIGHBOR_FLAG_DYNAMIC;
-    }
-
-  adj_nbr_walk_nh4 (sw_if_index, &e->ip4_address, arp_mk_complete_walk, e);
-
-check_customers:
-  /* Customer(s) waiting for this address to be resolved? */
-  p = hash_get (am->pending_resolutions_by_address, args->ip4.as_u32);
-  if (p)
-    {
-      u32 next_index;
-      next_index = p[0];
-
-      while (next_index != (u32) ~ 0)
-	{
-	  pr = pool_elt_at_index (am->pending_resolutions, next_index);
-	  vlib_process_signal_event (vm, pr->node_index,
-				     pr->type_opaque, pr->data);
-	  next_index = pr->next_index;
-	  pool_put (am->pending_resolutions, pr);
-	}
-
-      hash_unset (am->pending_resolutions_by_address, args->ip4.as_u32);
-    }
-
-  /* Customer(s) requesting ARP event for this address? */
-  p = hash_get (am->mac_changes_by_address, args->ip4.as_u32);
-  if (p)
-    {
-      u32 next_index;
-      next_index = p[0];
-
-      while (next_index != (u32) ~ 0)
-	{
-	  int rv = 1;
-	  mc = pool_elt_at_index (am->mac_changes, next_index);
-
-	  /* Call the user's data callback, return 1 to suppress dup events */
-	  if (mc->data_callback)
-	    rv = (mc->data_callback) (mc->data, &args->mac, sw_if_index, 0);
-
-	  /*
-	   * Signal the resolver process, as long as the user
-	   * says they want to be notified
-	   */
-	  if (rv == 0)
-	    vlib_process_signal_event (vm, mc->node_index,
-				       mc->type_opaque, mc->data);
-	  next_index = mc->next_index;
-	}
-    }
-
-  return 0;
-}
-
-void
-vnet_register_ip4_arp_resolution_event (vnet_main_t * vnm,
-					void *address_arg,
-					uword node_index,
-					uword type_opaque, uword data)
-{
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-  ip4_address_t *address = address_arg;
-  uword *p;
-  pending_resolution_t *pr;
-
-  pool_get (am->pending_resolutions, pr);
-
-  pr->next_index = ~0;
-  pr->node_index = node_index;
-  pr->type_opaque = type_opaque;
-  pr->data = data;
-  pr->data_callback = 0;
-
-  p = hash_get (am->pending_resolutions_by_address, address->as_u32);
-  if (p)
-    {
-      /* Insert new resolution at the head of the list */
-      pr->next_index = p[0];
-      hash_unset (am->pending_resolutions_by_address, address->as_u32);
-    }
-
-  hash_set (am->pending_resolutions_by_address, address->as_u32,
-	    pr - am->pending_resolutions);
-}
-
-int
-vnet_add_del_ip4_arp_change_event (vnet_main_t * vnm,
-				   arp_change_event_cb_t data_callback,
-				   u32 pid,
-				   void *address_arg,
-				   uword node_index,
-				   uword type_opaque, uword data, int is_add)
-{
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-  ip4_address_t *address = address_arg;
-
-  /* Try to find an existing entry */
-  u32 *first = (u32 *) hash_get (am->mac_changes_by_address, address->as_u32);
-  u32 *p = first;
-  pending_resolution_t *mc;
-  while (p && *p != ~0)
-    {
-      mc = pool_elt_at_index (am->mac_changes, *p);
-      if (mc->node_index == node_index && mc->type_opaque == type_opaque
-	  && mc->pid == pid)
-	break;
-      p = &mc->next_index;
-    }
-
-  int found = p && *p != ~0;
-  if (is_add)
-    {
-      if (found)
-	return VNET_API_ERROR_ENTRY_ALREADY_EXISTS;
-
-      pool_get (am->mac_changes, mc);
-      /* *INDENT-OFF* */
-      *mc = (pending_resolution_t)
-      {
-        .next_index = ~0,
-        .node_index = node_index,
-        .type_opaque = type_opaque,
-        .data = data,
-        .data_callback = data_callback,
-        .pid = pid,
-      };
-      /* *INDENT-ON* */
-
-      /* Insert new resolution at the end of the list */
-      u32 new_idx = mc - am->mac_changes;
-      if (p)
-	p[0] = new_idx;
-      else
-	hash_set (am->mac_changes_by_address, address->as_u32, new_idx);
-    }
-  else
-    {
-      if (!found)
-	return VNET_API_ERROR_NO_SUCH_ENTRY;
-
-      /* Clients may need to clean up pool entries, too */
-      if (data_callback)
-	/* no new mac addrs */
-	(data_callback) (mc->data, NULL, ~0, NULL);
-
-      /* Remove the entry from the list and delete the entry */
-      *p = mc->next_index;
-      pool_put (am->mac_changes, mc);
-
-      /* Remove from hash if we deleted the last entry */
-      if (*p == ~0 && p == first)
-	hash_unset (am->mac_changes_by_address, address->as_u32);
-    }
-  return 0;
-}
-
-/* Either we drop the packet or we send a reply to the sender. */
-typedef enum
-{
-  ARP_REPLY_NEXT_DROP,
-  ARP_REPLY_NEXT_REPLY_TX,
-  ARP_REPLY_N_NEXT,
-} arp_reply_next_t;
-
-#define foreach_ethernet_arp_error					\
-  _ (replies_sent, "ARP replies sent")					\
-  _ (l2_type_not_ethernet, "L2 type not ethernet")			\
-  _ (l3_type_not_ip4, "L3 type not IP4")				\
-  _ (l3_src_address_not_local, "IP4 source address not local to subnet") \
-  _ (l3_dst_address_not_local, "IP4 destination address not local to subnet") \
-  _ (l3_dst_address_unset, "IP4 destination address is unset")          \
-  _ (l3_src_address_is_local, "IP4 source address matches local interface") \
-  _ (l3_src_address_learned, "ARP request IP4 source address learned")  \
-  _ (replies_received, "ARP replies received")				\
-  _ (opcode_not_request, "ARP opcode not request")                      \
-  _ (proxy_arp_replies_sent, "Proxy ARP replies sent")			\
-  _ (l2_address_mismatch, "ARP hw addr does not match L2 frame src addr") \
-  _ (gratuitous_arp, "ARP probe or announcement dropped") \
-  _ (interface_no_table, "Interface is not mapped to an IP table") \
-  _ (interface_not_ip_enabled, "Interface is not IP enabled") \
-  _ (unnumbered_mismatch, "RX interface is unnumbered to different subnet") \
-
-typedef enum
-{
-#define _(sym,string) ETHERNET_ARP_ERROR_##sym,
-  foreach_ethernet_arp_error
-#undef _
-    ETHERNET_ARP_N_ERROR,
-} ethernet_arp_reply_error_t;
-
-static int
-arp_unnumbered (vlib_buffer_t * p0,
-		u32 input_sw_if_index, u32 conn_sw_if_index)
-{
-  vnet_main_t *vnm = vnet_get_main ();
-  vnet_interface_main_t *vim = &vnm->interface_main;
-  vnet_sw_interface_t *si;
-
-  /* verify that the input interface is unnumbered to the connected.
-   * the connected interface is the interface on which the subnet is
-   * configured */
-  si = &vim->sw_interfaces[input_sw_if_index];
-
-  if (!(si->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED &&
-	(si->unnumbered_sw_if_index == conn_sw_if_index)))
-    {
-      /* the input interface is not unnumbered to the interface on which
-       * the sub-net is configured that covers the ARP request.
-       * So this is not the case for unnumbered.. */
-      return 0;
-    }
-
-  return !0;
-}
-
-static u32
-arp_learn (vnet_main_t * vnm,
-	   ethernet_arp_main_t * am, u32 sw_if_index,
-	   const ethernet_arp_ip4_over_ethernet_address_t * addr)
-{
-  vnet_arp_set_ip4_over_ethernet (vnm, sw_if_index, addr, 0);
-  return (ETHERNET_ARP_ERROR_l3_src_address_learned);
-}
-
-typedef enum arp_input_next_t_
-{
-  ARP_INPUT_NEXT_DROP,
-  ARP_INPUT_NEXT_DISABLED,
-  ARP_INPUT_N_NEXT,
-} arp_input_next_t;
-
-static uword
-arp_input (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
-{
-  u32 n_left_from, next_index, *from, *to_next, n_left_to_next;
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-
-  from = vlib_frame_vector_args (frame);
-  n_left_from = frame->n_vectors;
-  next_index = node->cached_next_index;
-
-  if (node->flags & VLIB_NODE_FLAG_TRACE)
-    vlib_trace_frame_buffers_only (vm, node, from, frame->n_vectors,
-				   /* stride */ 1,
-				   sizeof (ethernet_arp_input_trace_t));
-
-  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_arp_header_t *arp0;
-	  arp_input_next_t next0;
-	  vlib_buffer_t *p0;
-	  u32 pi0, error0;
-
-	  pi0 = to_next[0] = from[0];
-	  from += 1;
-	  to_next += 1;
-	  n_left_from -= 1;
-	  n_left_to_next -= 1;
-
-	  p0 = vlib_get_buffer (vm, pi0);
-	  arp0 = vlib_buffer_get_current (p0);
-
-	  error0 = ETHERNET_ARP_ERROR_replies_sent;
-	  next0 = ARP_INPUT_NEXT_DROP;
-
-	  error0 =
-	    (arp0->l2_type !=
-	     clib_net_to_host_u16 (ETHERNET_ARP_HARDWARE_TYPE_ethernet) ?
-	     ETHERNET_ARP_ERROR_l2_type_not_ethernet : error0);
-	  error0 =
-	    (arp0->l3_type !=
-	     clib_net_to_host_u16 (ETHERNET_TYPE_IP4) ?
-	     ETHERNET_ARP_ERROR_l3_type_not_ip4 : error0);
-	  error0 =
-	    (0 == arp0->ip4_over_ethernet[0].ip4.as_u32 ?
-	     ETHERNET_ARP_ERROR_l3_dst_address_unset : error0);
-
-	  if (ETHERNET_ARP_ERROR_replies_sent == error0)
-	    {
-	      next0 = ARP_INPUT_NEXT_DISABLED;
-	      vnet_feature_arc_start (am->feature_arc_index,
-				      vnet_buffer (p0)->sw_if_index[VLIB_RX],
-				      &next0, p0);
-	    }
-	  else
-	    p0->error = node->errors[error0];
-
-	  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);
-    }
-
-  return frame->n_vectors;
-}
-
-typedef enum arp_disabled_next_t_
-{
-  ARP_DISABLED_NEXT_DROP,
-  ARP_DISABLED_N_NEXT,
-} arp_disabled_next_t;
-
-#define foreach_arp_disabled_error					\
-  _ (DISABLED, "ARP Disabled on this interface")                    \
-
-typedef enum
-{
-#define _(sym,string) ARP_DISABLED_ERROR_##sym,
-  foreach_arp_disabled_error
-#undef _
-    ARP_DISABLED_N_ERROR,
-} arp_disabled_error_t;
-
-static char *arp_disabled_error_strings[] = {
-#define _(sym,string) string,
-  foreach_arp_disabled_error
-#undef _
-};
-
-static uword
-arp_disabled (vlib_main_t * vm,
-	      vlib_node_runtime_t * node, vlib_frame_t * frame)
-{
-  u32 n_left_from, next_index, *from, *to_next, n_left_to_next;
-
-  from = vlib_frame_vector_args (frame);
-  n_left_from = frame->n_vectors;
-  next_index = node->cached_next_index;
-
-  if (node->flags & VLIB_NODE_FLAG_TRACE)
-    vlib_trace_frame_buffers_only (vm, node, from, frame->n_vectors,
-				   /* stride */ 1,
-				   sizeof (ethernet_arp_input_trace_t));
-
-  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)
-	{
-	  arp_disabled_next_t next0 = ARP_DISABLED_NEXT_DROP;
-	  vlib_buffer_t *p0;
-	  u32 pi0, error0;
-
-	  next0 = ARP_DISABLED_NEXT_DROP;
-	  error0 = ARP_DISABLED_ERROR_DISABLED;
-
-	  pi0 = to_next[0] = from[0];
-	  from += 1;
-	  to_next += 1;
-	  n_left_from -= 1;
-	  n_left_to_next -= 1;
-
-	  p0 = vlib_get_buffer (vm, pi0);
-	  p0->error = node->errors[error0];
-
-	  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);
-    }
-
-  return frame->n_vectors;
-}
-
-static_always_inline u32
-arp_mk_reply (vnet_main_t * vnm,
-	      vlib_buffer_t * p0,
-	      u32 sw_if_index0,
-	      const ip4_address_t * if_addr0,
-	      ethernet_arp_header_t * arp0, ethernet_header_t * eth_rx)
-{
-  vnet_hw_interface_t *hw_if0;
-  u8 *rewrite0, rewrite0_len;
-  ethernet_header_t *eth_tx;
-  u32 next0;
-
-  /* Send a reply.
-     An adjacency to the sender is not always present,
-     so we use the interface to build us a rewrite string
-     which will contain all the necessary tags. */
-  rewrite0 = ethernet_build_rewrite (vnm, sw_if_index0,
-				     VNET_LINK_ARP, eth_rx->src_address);
-  rewrite0_len = vec_len (rewrite0);
-
-  /* Figure out how much to rewind current data from adjacency. */
-  vlib_buffer_advance (p0, -rewrite0_len);
-  eth_tx = vlib_buffer_get_current (p0);
-
-  vnet_buffer (p0)->sw_if_index[VLIB_TX] = sw_if_index0;
-  hw_if0 = vnet_get_sup_hw_interface (vnm, sw_if_index0);
-
-  /* Send reply back through input interface */
-  vnet_buffer (p0)->sw_if_index[VLIB_TX] = sw_if_index0;
-  next0 = ARP_REPLY_NEXT_REPLY_TX;
-
-  arp0->opcode = clib_host_to_net_u16 (ETHERNET_ARP_OPCODE_reply);
-
-  arp0->ip4_over_ethernet[1] = arp0->ip4_over_ethernet[0];
-
-  mac_address_from_bytes (&arp0->ip4_over_ethernet[0].mac,
-			  hw_if0->hw_address);
-  clib_mem_unaligned (&arp0->ip4_over_ethernet[0].ip4.data_u32, u32) =
-    if_addr0->data_u32;
-
-  /* Hardware must be ethernet-like. */
-  ASSERT (vec_len (hw_if0->hw_address) == 6);
-
-  /* the rx nd tx ethernet headers wil overlap in the case
-   * when we received a tagged VLAN=0 packet, but we are sending
-   * back untagged */
-  clib_memcpy_fast (eth_tx, rewrite0, vec_len (rewrite0));
-  vec_free (rewrite0);
-
-  return (next0);
-}
-
-enum arp_dst_fib_type
-{
-  ARP_DST_FIB_NONE,
-  ARP_DST_FIB_ADJ,
-  ARP_DST_FIB_CONN
-};
-
-/*
- * we're looking for FIB sources that indicate the destination
- * is attached. There may be interposed DPO prior to the one
- * we are looking for
- */
-static enum arp_dst_fib_type
-arp_dst_fib_check (const fib_node_index_t fei, fib_entry_flag_t * flags)
-{
-  const fib_entry_t *entry = fib_entry_get (fei);
-  const fib_entry_src_t *entry_src;
-  fib_source_t src;
-  /* *INDENT-OFF* */
-  FOR_EACH_SRC_ADDED(entry, entry_src, src,
-  ({
-    *flags = fib_entry_get_flags_for_source (fei, src);
-    if (fib_entry_is_sourced (fei, FIB_SOURCE_ADJ))
-        return ARP_DST_FIB_ADJ;
-      else if (FIB_ENTRY_FLAG_CONNECTED & *flags)
-        return ARP_DST_FIB_CONN;
-  }))
-  /* *INDENT-ON* */
-
-  return ARP_DST_FIB_NONE;
-}
-
-static uword
-arp_reply (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
-{
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-  vnet_main_t *vnm = vnet_get_main ();
-  u32 n_left_from, next_index, *from, *to_next;
-  u32 n_replies_sent = 0;
-
-  from = vlib_frame_vector_args (frame);
-  n_left_from = frame->n_vectors;
-  next_index = node->cached_next_index;
-
-  if (node->flags & VLIB_NODE_FLAG_TRACE)
-    vlib_trace_frame_buffers_only (vm, node, from, frame->n_vectors,
-				   /* stride */ 1,
-				   sizeof (ethernet_arp_input_trace_t));
-
-  while (n_left_from > 0)
-    {
-      u32 n_left_to_next;
-
-      vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
-
-      while (n_left_from > 0 && n_left_to_next > 0)
-	{
-	  vlib_buffer_t *p0;
-	  ethernet_arp_header_t *arp0;
-	  ethernet_header_t *eth_rx;
-	  const ip4_address_t *if_addr0;
-	  u32 pi0, error0, next0, sw_if_index0, conn_sw_if_index0, fib_index0;
-	  u8 dst_is_local0, is_vrrp_reply0;
-	  fib_node_index_t dst_fei, src_fei;
-	  const fib_prefix_t *pfx0;
-	  fib_entry_flag_t src_flags, dst_flags;
-
-	  pi0 = from[0];
-	  to_next[0] = pi0;
-	  from += 1;
-	  to_next += 1;
-	  n_left_from -= 1;
-	  n_left_to_next -= 1;
-
-	  p0 = vlib_get_buffer (vm, pi0);
-	  arp0 = vlib_buffer_get_current (p0);
-	  /* Fill in ethernet header. */
-	  eth_rx = ethernet_buffer_get_header (p0);
-
-	  next0 = ARP_REPLY_NEXT_DROP;
-	  error0 = ETHERNET_ARP_ERROR_replies_sent;
-	  sw_if_index0 = vnet_buffer (p0)->sw_if_index[VLIB_RX];
-
-	  /* Check that IP address is local and matches incoming interface. */
-	  fib_index0 = ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
-	  if (~0 == fib_index0)
-	    {
-	      error0 = ETHERNET_ARP_ERROR_interface_no_table;
-	      goto drop;
-
-	    }
-
-	  {
-	    /*
-	     * we're looking for FIB entries that indicate the source
-	     * is attached. There may be more specific non-attached
-	     * routes that match the source, but these do not influence
-	     * whether we respond to an ARP request, i.e. they do not
-	     * influence whether we are the correct way for the sender
-	     * to reach us, they only affect how we reach the sender.
-	     */
-	    fib_entry_t *src_fib_entry;
-	    const fib_prefix_t *pfx;
-	    fib_entry_src_t *src;
-	    fib_source_t source;
-	    int attached;
-	    int mask;
-
-	    mask = 32;
-	    attached = 0;
-
-	    do
-	      {
-		src_fei = ip4_fib_table_lookup (ip4_fib_get (fib_index0),
-						&arp0->
-						ip4_over_ethernet[0].ip4,
-						mask);
-		src_fib_entry = fib_entry_get (src_fei);
-
-		/*
-		 * It's possible that the source that provides the
-		 * flags we need, or the flags we must not have,
-		 * is not the best source, so check then all.
-		 */
-                /* *INDENT-OFF* */
-                FOR_EACH_SRC_ADDED(src_fib_entry, src, source,
-                ({
-                  src_flags = fib_entry_get_flags_for_source (src_fei, source);
-
-                  /* Reject requests/replies with our local interface
-                     address. */
-                  if (FIB_ENTRY_FLAG_LOCAL & src_flags)
-                    {
-                      error0 = ETHERNET_ARP_ERROR_l3_src_address_is_local;
-                      /*
-                       * When VPP has an interface whose address is also
-                       * applied to a TAP interface on the host, then VPP's
-                       * TAP interface will be unnumbered  to the 'real'
-                       * interface and do proxy ARP from the host.
-                       * The curious aspect of this setup is that ARP requests
-                       * from the host will come from the VPP's own address.
-                       * So don't drop immediately here, instead go see if this
-                       * is a proxy ARP case.
-                       */
-                      goto next_feature;
-                    }
-                  /* A Source must also be local to subnet of matching
-                   * interface address. */
-                  if ((FIB_ENTRY_FLAG_ATTACHED & src_flags) ||
-                      (FIB_ENTRY_FLAG_CONNECTED & src_flags))
-                    {
-                      attached = 1;
-                      break;
-                    }
-                  /*
-                   * else
-                   *  The packet was sent from an address that is not
-                   *  connected nor attached i.e. it is not from an
-                   *  address that is covered by a link's sub-net,
-                   *  nor is it a already learned host resp.
-                   */
-                }));
-                /* *INDENT-ON* */
-
-		/*
-		 * shorter mask lookup for the next iteration.
-		 */
-		pfx = fib_entry_get_prefix (src_fei);
-		mask = pfx->fp_len - 1;
-
-		/*
-		 * continue until we hit the default route or we find
-		 * the attached we are looking for. The most likely
-		 * outcome is we find the attached with the first source
-		 * on the first lookup.
-		 */
-	      }
-	    while (!attached &&
-		   !fib_entry_is_sourced (src_fei, FIB_SOURCE_DEFAULT_ROUTE));
-
-	    if (!attached)
-	      {
-		/*
-		 * the matching route is a not attached, i.e. it was
-		 * added as a result of routing, rather than interface/ARP
-		 * configuration. If the matching route is not a host route
-		 * (i.e. a /32)
-		 */
-		error0 = ETHERNET_ARP_ERROR_l3_src_address_not_local;
-		goto drop;
-	      }
-	  }
-
-	  dst_fei = ip4_fib_table_lookup (ip4_fib_get (fib_index0),
-					  &arp0->ip4_over_ethernet[1].ip4,
-					  32);
-	  switch (arp_dst_fib_check (dst_fei, &dst_flags))
-	    {
-	    case ARP_DST_FIB_ADJ:
-	      /*
-	       * We matched an adj-fib on ths source subnet (a /32 previously
-	       * added as a result of ARP). If this request is a gratuitous
-	       * ARP, then learn from it.
-	       * The check for matching an adj-fib, is to prevent hosts
-	       * from spamming us with gratuitous ARPS that might otherwise
-	       * blow our ARP cache
-	       */
-	      if (arp0->ip4_over_ethernet[0].ip4.as_u32 ==
-		  arp0->ip4_over_ethernet[1].ip4.as_u32)
-		error0 = arp_learn (vnm, am, sw_if_index0,
-				    &arp0->ip4_over_ethernet[0]);
-	      goto drop;
-	    case ARP_DST_FIB_CONN:
-	      /* destination is connected, continue to process */
-	      break;
-	    case ARP_DST_FIB_NONE:
-	      /* destination is not connected, stop here */
-	      error0 = ETHERNET_ARP_ERROR_l3_dst_address_not_local;
-	      goto next_feature;
-	    }
-
-	  dst_is_local0 = (FIB_ENTRY_FLAG_LOCAL & dst_flags);
-	  pfx0 = fib_entry_get_prefix (dst_fei);
-	  if_addr0 = &pfx0->fp_addr.ip4;
-
-	  is_vrrp_reply0 =
-	    ((arp0->opcode ==
-	      clib_host_to_net_u16 (ETHERNET_ARP_OPCODE_reply))
-	     &&
-	     (!memcmp
-	      (arp0->ip4_over_ethernet[0].mac.bytes, vrrp_prefix,
-	       sizeof (vrrp_prefix))));
-
-	  /* Trash ARP packets whose ARP-level source addresses do not
-	     match their L2-frame-level source addresses, unless it's
-	     a reply from a VRRP virtual router */
-	  if (!ethernet_mac_address_equal
-	      (eth_rx->src_address,
-	       arp0->ip4_over_ethernet[0].mac.bytes) && !is_vrrp_reply0)
-	    {
-	      error0 = ETHERNET_ARP_ERROR_l2_address_mismatch;
-	      goto drop;
-	    }
-
-	  /* Learn or update sender's mapping only for replies to addresses
-	   * that are local to the subnet */
-	  if (arp0->opcode ==
-	      clib_host_to_net_u16 (ETHERNET_ARP_OPCODE_reply))
-	    {
-	      if (dst_is_local0)
-		error0 = arp_learn (vnm, am, sw_if_index0,
-				    &arp0->ip4_over_ethernet[0]);
-	      else
-		/* a reply for a non-local destination could be a GARP.
-		 * GARPs for hosts we know were handled above, so this one
-		 * we drop */
-		error0 = ETHERNET_ARP_ERROR_l3_dst_address_not_local;
-
-	      goto next_feature;
-	    }
-	  else if (arp0->opcode ==
-		   clib_host_to_net_u16 (ETHERNET_ARP_OPCODE_request) &&
-		   (dst_is_local0 == 0))
-	    {
-	      goto next_feature;
-	    }
-
-	  /* Honor unnumbered interface, if any */
-	  conn_sw_if_index0 = fib_entry_get_resolving_interface (dst_fei);
-	  if (sw_if_index0 != conn_sw_if_index0 ||
-	      sw_if_index0 != fib_entry_get_resolving_interface (src_fei))
-	    {
-	      /*
-	       * The interface the ARP is sent to or was received on is not the
-	       * interface on which the covering prefix is configured.
-	       * Maybe this is a case for unnumbered.
-	       */
-	      if (!arp_unnumbered (p0, sw_if_index0, conn_sw_if_index0))
-		{
-		  error0 = ETHERNET_ARP_ERROR_unnumbered_mismatch;
-		  goto drop;
-		}
-	    }
-	  if (arp0->ip4_over_ethernet[0].ip4.as_u32 ==
-	      arp0->ip4_over_ethernet[1].ip4.as_u32)
-	    {
-	      error0 = ETHERNET_ARP_ERROR_gratuitous_arp;
-	      goto drop;
-	    }
-
-	  next0 = arp_mk_reply (vnm, p0, sw_if_index0,
-				if_addr0, arp0, eth_rx);
-
-	  /* We are going to reply to this request, so, in the absence of
-	     errors, learn the sender */
-	  if (!error0)
-	    error0 = arp_learn (vnm, am, sw_if_index0,
-				&arp0->ip4_over_ethernet[1]);
-
-	  n_replies_sent += 1;
-	  goto enqueue;
-
-	next_feature:
-	  vnet_feature_next (&next0, p0);
-	  goto enqueue;
-
-	drop:
-	  p0->error = node->errors[error0];
-
-	enqueue:
-	  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);
-    }
-
-  vlib_error_count (vm, node->node_index,
-		    ETHERNET_ARP_ERROR_replies_sent, n_replies_sent);
-
-  return frame->n_vectors;
-}
-
-static uword
-arp_proxy (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
-{
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-  vnet_main_t *vnm = vnet_get_main ();
-  u32 n_left_from, next_index, *from, *to_next;
-  u32 n_arp_replies_sent = 0;
-
-  from = vlib_frame_vector_args (frame);
-  n_left_from = frame->n_vectors;
-  next_index = node->cached_next_index;
-
-  if (node->flags & VLIB_NODE_FLAG_TRACE)
-    vlib_trace_frame_buffers_only (vm, node, from, frame->n_vectors,
-				   /* stride */ 1,
-				   sizeof (ethernet_arp_input_trace_t));
-
-  while (n_left_from > 0)
-    {
-      u32 n_left_to_next;
-
-      vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
-
-      while (n_left_from > 0 && n_left_to_next > 0)
-	{
-	  vlib_buffer_t *p0;
-	  ethernet_arp_header_t *arp0;
-	  ethernet_header_t *eth_rx;
-	  ip4_address_t proxy_src;
-	  u32 pi0, error0, next0, sw_if_index0, fib_index0;
-	  u8 is_request0;
-	  ethernet_proxy_arp_t *pa;
-
-	  pi0 = from[0];
-	  to_next[0] = pi0;
-	  from += 1;
-	  to_next += 1;
-	  n_left_from -= 1;
-	  n_left_to_next -= 1;
-
-	  p0 = vlib_get_buffer (vm, pi0);
-	  arp0 = vlib_buffer_get_current (p0);
-	  /* Fill in ethernet header. */
-	  eth_rx = ethernet_buffer_get_header (p0);
-
-	  is_request0 = arp0->opcode
-	    == clib_host_to_net_u16 (ETHERNET_ARP_OPCODE_request);
-
-	  error0 = ETHERNET_ARP_ERROR_replies_sent;
-	  sw_if_index0 = vnet_buffer (p0)->sw_if_index[VLIB_RX];
-	  next0 = ARP_REPLY_NEXT_DROP;
-
-	  fib_index0 = ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
-	  if (~0 == fib_index0)
-	    {
-	      error0 = ETHERNET_ARP_ERROR_interface_no_table;
-	    }
-
-	  if (0 == error0 && is_request0)
-	    {
-	      u32 this_addr = clib_net_to_host_u32
-		(arp0->ip4_over_ethernet[1].ip4.as_u32);
-
-	      vec_foreach (pa, am->proxy_arps)
-	      {
-		u32 lo_addr = clib_net_to_host_u32 (pa->lo_addr.as_u32);
-		u32 hi_addr = clib_net_to_host_u32 (pa->hi_addr.as_u32);
-
-		/* an ARP request hit in the proxy-arp table? */
-		if ((this_addr >= lo_addr && this_addr <= hi_addr) &&
-		    (fib_index0 == pa->fib_index))
-		  {
-		    proxy_src.as_u32 =
-		      arp0->ip4_over_ethernet[1].ip4.data_u32;
-
-		    /*
-		     * change the interface address to the proxied
-		     */
-		    n_arp_replies_sent++;
-
-		    next0 =
-		      arp_mk_reply (vnm, p0, sw_if_index0, &proxy_src, arp0,
-				    eth_rx);
-		  }
-	      }
-	    }
-	  else
-	    {
-	      p0->error = node->errors[error0];
-	    }
-
-	  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);
-    }
-
-  vlib_error_count (vm, node->node_index,
-		    ETHERNET_ARP_ERROR_replies_sent, n_arp_replies_sent);
-
-  return frame->n_vectors;
-}
-
-static char *ethernet_arp_error_strings[] = {
-#define _(sym,string) string,
-  foreach_ethernet_arp_error
-#undef _
-};
-
-/* *INDENT-OFF* */
-
-VLIB_REGISTER_NODE (arp_input_node, static) =
-{
-  .function = arp_input,
-  .name = "arp-input",
-  .vector_size = sizeof (u32),
-  .n_errors = ETHERNET_ARP_N_ERROR,
-  .error_strings = ethernet_arp_error_strings,
-  .n_next_nodes = ARP_INPUT_N_NEXT,
-  .next_nodes = {
-    [ARP_INPUT_NEXT_DROP] = "error-drop",
-    [ARP_INPUT_NEXT_DISABLED] = "arp-disabled",
-  },
-  .format_buffer = format_ethernet_arp_header,
-  .format_trace = format_ethernet_arp_input_trace,
-};
-
-VLIB_REGISTER_NODE (arp_disabled_node, static) =
-{
-  .function = arp_disabled,
-  .name = "arp-disabled",
-  .vector_size = sizeof (u32),
-  .n_errors = ARP_DISABLED_N_ERROR,
-  .error_strings = arp_disabled_error_strings,
-  .n_next_nodes = ARP_DISABLED_N_NEXT,
-  .next_nodes = {
-    [ARP_INPUT_NEXT_DROP] = "error-drop",
-  },
-  .format_buffer = format_ethernet_arp_header,
-  .format_trace = format_ethernet_arp_input_trace,
-};
-
-VLIB_REGISTER_NODE (arp_reply_node, static) =
-{
-  .function = arp_reply,
-  .name = "arp-reply",
-  .vector_size = sizeof (u32),
-  .n_errors = ETHERNET_ARP_N_ERROR,
-  .error_strings = ethernet_arp_error_strings,
-  .n_next_nodes = ARP_REPLY_N_NEXT,
-  .next_nodes = {
-    [ARP_REPLY_NEXT_DROP] = "error-drop",
-    [ARP_REPLY_NEXT_REPLY_TX] = "interface-output",
-  },
-  .format_buffer = format_ethernet_arp_header,
-  .format_trace = format_ethernet_arp_input_trace,
-};
-
-VLIB_REGISTER_NODE (arp_proxy_node, static) =
-{
-  .function = arp_proxy,
-  .name = "arp-proxy",
-  .vector_size = sizeof (u32),
-  .n_errors = ETHERNET_ARP_N_ERROR,
-  .error_strings = ethernet_arp_error_strings,
-  .n_next_nodes = ARP_REPLY_N_NEXT,
-  .next_nodes = {
-    [ARP_REPLY_NEXT_DROP] = "error-drop",
-    [ARP_REPLY_NEXT_REPLY_TX] = "interface-output",
-  },
-  .format_buffer = format_ethernet_arp_header,
-  .format_trace = format_ethernet_arp_input_trace,
-};
-
-/* Built-in ARP rx feature path definition */
-VNET_FEATURE_ARC_INIT (arp_feat, static) =
-{
-  .arc_name = "arp",
-  .start_nodes = VNET_FEATURES ("arp-input"),
-  .last_in_arc = "error-drop",
-  .arc_index_ptr = &ethernet_arp_main.feature_arc_index,
-};
-
-VNET_FEATURE_INIT (arp_reply_feat_node, static) =
-{
-  .arc_name = "arp",
-  .node_name = "arp-reply",
-  .runs_before = VNET_FEATURES ("arp-disabled"),
-};
-
-VNET_FEATURE_INIT (arp_proxy_feat_node, static) =
-{
-  .arc_name = "arp",
-  .node_name = "arp-proxy",
-  .runs_after = VNET_FEATURES ("arp-reply"),
-  .runs_before = VNET_FEATURES ("arp-disabled"),
-};
-
-VNET_FEATURE_INIT (arp_disabled_feat_node, static) =
-{
-  .arc_name = "arp",
-  .node_name = "arp-disabled",
-  .runs_before = VNET_FEATURES ("error-drop"),
-};
-
-VNET_FEATURE_INIT (arp_drop_feat_node, static) =
-{
-  .arc_name = "arp",
-  .node_name = "error-drop",
-  .runs_before = 0,	/* last feature */
-};
-
-/* *INDENT-ON* */
-
-static int
-ip4_arp_entry_sort (void *a1, void *a2)
-{
-  ethernet_arp_ip4_entry_t *e1 = a1;
-  ethernet_arp_ip4_entry_t *e2 = a2;
-
-  int cmp;
-  vnet_main_t *vnm = vnet_get_main ();
-
-  cmp = vnet_sw_interface_compare (vnm, e1->sw_if_index, e2->sw_if_index);
-  if (!cmp)
-    cmp = ip4_address_compare (&e1->ip4_address, &e2->ip4_address);
-  return cmp;
-}
-
-ethernet_arp_ip4_entry_t *
-ip4_neighbors_pool (void)
-{
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-  return am->ip4_entry_pool;
-}
-
-ethernet_arp_ip4_entry_t *
-ip4_neighbor_entries (u32 sw_if_index)
-{
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-  ethernet_arp_ip4_entry_t *n, *ns = 0;
-
-  /* *INDENT-OFF* */
-  pool_foreach (n, am->ip4_entry_pool, ({
-    if (sw_if_index != ~0 && n->sw_if_index != sw_if_index)
-      continue;
-    vec_add1 (ns, n[0]);
-  }));
-  /* *INDENT-ON* */
-
-  if (ns)
-    vec_sort_with_function (ns, ip4_arp_entry_sort);
-  return ns;
-}
-
-static clib_error_t *
-show_ip4_arp (vlib_main_t * vm,
-	      unformat_input_t * input, vlib_cli_command_t * cmd)
-{
-  vnet_main_t *vnm = vnet_get_main ();
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-  ethernet_arp_ip4_entry_t *e, *es;
-  ethernet_proxy_arp_t *pa;
-  clib_error_t *error = 0;
-  u32 sw_if_index;
-
-  /* Filter entries by interface if given. */
-  sw_if_index = ~0;
-  (void) unformat_user (input, unformat_vnet_sw_interface, vnm, &sw_if_index);
-
-  es = ip4_neighbor_entries (sw_if_index);
-  if (es)
-    {
-      vlib_cli_output (vm, "%U", format_ethernet_arp_ip4_entry, vnm, 0);
-      vec_foreach (e, es)
-      {
-	vlib_cli_output (vm, "%U", format_ethernet_arp_ip4_entry, vnm, e);
-      }
-      vec_free (es);
-    }
-
-  if (vec_len (am->proxy_arps))
-    {
-      vlib_cli_output (vm, "Proxy arps enabled for:");
-      vec_foreach (pa, am->proxy_arps)
-      {
-	vlib_cli_output (vm, "Fib_index %d   %U - %U ",
-			 pa->fib_index,
-			 format_ip4_address, &pa->lo_addr,
-			 format_ip4_address, &pa->hi_addr);
-      }
-    }
-
-  return error;
-}
-
-/*?
- * Display all the IPv4 ARP entries.
- *
- * @cliexpar
- * Example of how to display the IPv4 ARP table:
- * @cliexstart{show ip arp}
- *    Time      FIB        IP4       Flags      Ethernet              Interface
- *    346.3028   0       6.1.1.3            de:ad:be:ef:ba:be   GigabitEthernet2/0/0
- *   3077.4271   0       6.1.1.4       S    de:ad:be:ef:ff:ff   GigabitEthernet2/0/0
- *   2998.6409   1       6.2.2.3            de:ad:be:ef:00:01   GigabitEthernet2/0/0
- * Proxy arps enabled for:
- * Fib_index 0   6.0.0.1 - 6.0.0.11
- * @cliexend
- ?*/
-/* *INDENT-OFF* */
-VLIB_CLI_COMMAND (show_ip4_arp_command, static) = {
-  .path = "show ip arp",
-  .function = show_ip4_arp,
-  .short_help = "show ip arp",
-};
-/* *INDENT-ON* */
-
-typedef struct
-{
-  pg_edit_t l2_type, l3_type;
-  pg_edit_t n_l2_address_bytes, n_l3_address_bytes;
-  pg_edit_t opcode;
-  struct
-  {
-    pg_edit_t mac;
-    pg_edit_t ip4;
-  } ip4_over_ethernet[2];
-} pg_ethernet_arp_header_t;
-
-static inline void
-pg_ethernet_arp_header_init (pg_ethernet_arp_header_t * p)
-{
-  /* Initialize fields that are not bit fields in the IP header. */
-#define _(f) pg_edit_init (&p->f, ethernet_arp_header_t, f);
-  _(l2_type);
-  _(l3_type);
-  _(n_l2_address_bytes);
-  _(n_l3_address_bytes);
-  _(opcode);
-  _(ip4_over_ethernet[0].mac);
-  _(ip4_over_ethernet[0].ip4);
-  _(ip4_over_ethernet[1].mac);
-  _(ip4_over_ethernet[1].ip4);
-#undef _
-}
-
-uword
-unformat_pg_arp_header (unformat_input_t * input, va_list * args)
-{
-  pg_stream_t *s = va_arg (*args, pg_stream_t *);
-  pg_ethernet_arp_header_t *p;
-  u32 group_index;
-
-  p = pg_create_edit_group (s, sizeof (p[0]), sizeof (ethernet_arp_header_t),
-			    &group_index);
-  pg_ethernet_arp_header_init (p);
-
-  /* Defaults. */
-  pg_edit_set_fixed (&p->l2_type, ETHERNET_ARP_HARDWARE_TYPE_ethernet);
-  pg_edit_set_fixed (&p->l3_type, ETHERNET_TYPE_IP4);
-  pg_edit_set_fixed (&p->n_l2_address_bytes, 6);
-  pg_edit_set_fixed (&p->n_l3_address_bytes, 4);
-
-  if (!unformat (input, "%U: %U/%U -> %U/%U",
-		 unformat_pg_edit,
-		 unformat_ethernet_arp_opcode_net_byte_order, &p->opcode,
-		 unformat_pg_edit,
-		 unformat_mac_address_t, &p->ip4_over_ethernet[0].mac,
-		 unformat_pg_edit,
-		 unformat_ip4_address, &p->ip4_over_ethernet[0].ip4,
-		 unformat_pg_edit,
-		 unformat_mac_address_t, &p->ip4_over_ethernet[1].mac,
-		 unformat_pg_edit,
-		 unformat_ip4_address, &p->ip4_over_ethernet[1].ip4))
-    {
-      /* Free up any edits we may have added. */
-      pg_free_edit_group (s);
-      return 0;
-    }
-  return 1;
-}
-
-clib_error_t *
-ip4_set_arp_limit (u32 arp_limit)
-{
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-
-  am->limit_arp_cache_size = arp_limit;
-  return 0;
-}
-
-/**
- * @brief Control Plane hook to remove an ARP entry
- */
-int
-vnet_arp_unset_ip4_over_ethernet (vnet_main_t * vnm,
-				  u32 sw_if_index,
-				  const
-				  ethernet_arp_ip4_over_ethernet_address_t *
-				  a)
-{
-  vnet_arp_set_ip4_over_ethernet_rpc_args_t args = {
-    .sw_if_index = sw_if_index,
-    .flags = ETHERNET_ARP_ARGS_REMOVE,
-    .ip4 = a->ip4,
-    .mac = a->mac,
-  };
-
-  vl_api_rpc_call_main_thread (set_ip4_over_ethernet_rpc_callback,
-			       (u8 *) & args, sizeof (args));
-  return 0;
-}
-
-/**
- * @brief publish wildcard arp event
- * @param sw_if_index The interface on which the ARP entries are acted
- */
-static int
-vnet_arp_wc_publish (u32 sw_if_index,
-		     const ethernet_arp_ip4_over_ethernet_address_t * a)
-{
-  vnet_arp_set_ip4_over_ethernet_rpc_args_t args = {
-    .flags = ETHERNET_ARP_ARGS_WC_PUB,
-    .sw_if_index = sw_if_index,
-    .ip4 = a->ip4,
-    .mac = a->mac,
-  };
-
-  vl_api_rpc_call_main_thread (set_ip4_over_ethernet_rpc_callback,
-			       (u8 *) & args, sizeof (args));
-  return 0;
-}
-
-static void
-vnet_arp_wc_publish_internal (vnet_main_t * vnm,
-			      vnet_arp_set_ip4_over_ethernet_rpc_args_t *
-			      args)
-{
-  vlib_main_t *vm = vlib_get_main ();
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-  uword ni = am->wc_ip4_arp_publisher_node;
-  uword et = am->wc_ip4_arp_publisher_et;
-
-  if (ni == (uword) ~ 0)
-    return;
-  wc_arp_report_t *r =
-    vlib_process_signal_event_data (vm, ni, et, 1, sizeof *r);
-  r->ip.as_u32 = args->ip4.as_u32;
-  r->sw_if_index = args->sw_if_index;
-  mac_address_copy (&r->mac, &args->mac);
-}
-
-void
-wc_arp_set_publisher_node (uword node_index, uword event_type)
-{
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-  am->wc_ip4_arp_publisher_node = node_index;
-  am->wc_ip4_arp_publisher_et = event_type;
-}
-
-static void
-arp_entry_free (ethernet_arp_interface_t * eai, ethernet_arp_ip4_entry_t * e);
-
-static int
-vnet_arp_flush_ip4_over_ethernet_internal (vnet_main_t * vnm,
-					   vnet_arp_set_ip4_over_ethernet_rpc_args_t
-					   * args)
-{
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-  ethernet_arp_ip4_entry_t *e;
-  ethernet_arp_interface_t *eai;
-
-  if (vec_len (am->ethernet_arp_by_sw_if_index) <= args->sw_if_index)
-    return 0;
-
-  eai = &am->ethernet_arp_by_sw_if_index[args->sw_if_index];
-
-  e = arp_entry_find (eai, &args->ip4);
-
-  if (NULL != e)
-    {
-      adj_nbr_walk_nh4 (e->sw_if_index,
-			&e->ip4_address, arp_mk_incomplete_walk, e);
-
-      /*
-       * The difference between flush and unset, is that an unset
-       * means delete for static and dynamic entries. A flush
-       * means delete only for dynamic. Flushing is what the DP
-       * does in response to interface events. unset is only done
-       * by the control plane.
-       */
-      if (e->flags & IP_NEIGHBOR_FLAG_STATIC)
-	{
-	  e->flags &= ~IP_NEIGHBOR_FLAG_DYNAMIC;
-	}
-      else if (e->flags & IP_NEIGHBOR_FLAG_DYNAMIC)
-	{
-	  arp_entry_free (eai, e);
-	}
-    }
-  return (0);
-}
-
-/*
- * arp_add_del_interface_address
- *
- * callback when an interface address is added or deleted
- */
-static void
-arp_enable_disable_interface (ip4_main_t * im,
-			      uword opaque, u32 sw_if_index, u32 is_enable)
-{
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-
-  if (is_enable)
-    arp_enable (am, sw_if_index);
-  else
-    arp_disable (am, sw_if_index);
-}
-
-/*
- * arp_add_del_interface_address
- *
- * callback when an interface address is added or deleted
- */
-static void
-arp_add_del_interface_address (ip4_main_t * im,
-			       uword opaque,
-			       u32 sw_if_index,
-			       ip4_address_t * address,
-			       u32 address_length,
-			       u32 if_address_index, u32 is_del)
-{
-  /*
-   * Flush the ARP cache of all entries covered by the address
-   * that is being removed.
-   */
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-  ethernet_arp_ip4_entry_t *e;
-
-  if (vec_len (am->ethernet_arp_by_sw_if_index) <= sw_if_index)
-    return;
-
-  if (is_del)
-    {
-      ethernet_arp_interface_t *eai;
-      u32 i, *to_delete = 0;
-      hash_pair_t *pair;
-
-      eai = &am->ethernet_arp_by_sw_if_index[sw_if_index];
-
-      /* *INDENT-OFF* */
-      hash_foreach_pair (pair, eai->arp_entries,
-      ({
-	e = pool_elt_at_index(am->ip4_entry_pool,
-			      pair->value[0]);
-	if (ip4_destination_matches_route (im, &e->ip4_address,
-					   address, address_length))
-	  {
-	    vec_add1 (to_delete, e - am->ip4_entry_pool);
-	  }
-      }));
-      /* *INDENT-ON* */
-
-      for (i = 0; i < vec_len (to_delete); i++)
-	{
-	  e = pool_elt_at_index (am->ip4_entry_pool, to_delete[i]);
-
-	  vnet_arp_set_ip4_over_ethernet_rpc_args_t delme = {
-	    .ip4.as_u32 = e->ip4_address.as_u32,
-	    .sw_if_index = e->sw_if_index,
-	    .flags = ETHERNET_ARP_ARGS_FLUSH,
-	  };
-	  mac_address_copy (&delme.mac, &e->mac);
-
-	  vnet_arp_flush_ip4_over_ethernet_internal (vnet_get_main (),
-						     &delme);
-	}
-
-      vec_free (to_delete);
-    }
-}
-
-static void
-arp_table_bind (ip4_main_t * im,
-		uword opaque,
-		u32 sw_if_index, u32 new_fib_index, u32 old_fib_index)
-{
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-  ethernet_arp_interface_t *eai;
-  ethernet_arp_ip4_entry_t *e;
-  hash_pair_t *pair;
-
-  /*
-   * the IP table that the interface is bound to has changed.
-   * reinstall all the adj fibs.
-   */
-
-  if (vec_len (am->ethernet_arp_by_sw_if_index) <= sw_if_index)
-    return;
-
-  eai = &am->ethernet_arp_by_sw_if_index[sw_if_index];
-
-  /* *INDENT-OFF* */
-  hash_foreach_pair (pair, eai->arp_entries,
-  ({
-    e = pool_elt_at_index(am->ip4_entry_pool,
-                          pair->value[0]);
-    /*
-     * remove the adj-fib from the old table and add to the new
-     */
-    arp_adj_fib_remove(e, old_fib_index);
-    arp_adj_fib_add(e, new_fib_index);
-  }));
-  /* *INDENT-ON* */
-
-}
-
-static clib_error_t *
-ethernet_arp_init (vlib_main_t * vm)
-{
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-  ip4_main_t *im = &ip4_main;
-  pg_node_t *pn;
-
-  ethernet_register_input_type (vm, ETHERNET_TYPE_ARP, arp_input_node.index);
-
-  pn = pg_get_node (arp_input_node.index);
-  pn->unformat_edit = unformat_pg_arp_header;
-
-  am->opcode_by_name = hash_create_string (0, sizeof (uword));
-#define _(o) hash_set_mem (am->opcode_by_name, #o, ETHERNET_ARP_OPCODE_##o);
-  foreach_ethernet_arp_opcode;
-#undef _
-
-  /* $$$ configurable */
-  am->limit_arp_cache_size = 50000;
-
-  am->pending_resolutions_by_address = hash_create (0, sizeof (uword));
-  am->mac_changes_by_address = hash_create (0, sizeof (uword));
-  am->wc_ip4_arp_publisher_node = (uword) ~ 0;
-
-  /* don't trace ARP error packets */
-  {
-    vlib_node_runtime_t *rt =
-      vlib_node_get_runtime (vm, arp_input_node.index);
-
-#define _(a,b)                                  \
-    vnet_pcap_drop_trace_filter_add_del         \
-        (rt->errors[ETHERNET_ARP_ERROR_##a],    \
-         1 /* is_add */);
-    foreach_ethernet_arp_error
-#undef _
-  }
-
-  ip4_add_del_interface_address_callback_t cb;
-  cb.function = arp_add_del_interface_address;
-  cb.function_opaque = 0;
-  vec_add1 (im->add_del_interface_address_callbacks, cb);
-
-  ip4_enable_disable_interface_callback_t cbe;
-  cbe.function = arp_enable_disable_interface;
-  cbe.function_opaque = 0;
-  vec_add1 (im->enable_disable_interface_callbacks, cbe);
-
-  ip4_table_bind_callback_t cbt;
-  cbt.function = arp_table_bind;
-  cbt.function_opaque = 0;
-  vec_add1 (im->table_bind_callbacks, cbt);
-
-  return 0;
-}
-/* *INDENT-OFF* */
-VLIB_INIT_FUNCTION (ethernet_arp_init) =
-{
-  .runs_after = VLIB_INITS("ethernet_init"),
-};
-/* *INDENT-ON* */
-
-static void
-arp_entry_free (ethernet_arp_interface_t * eai, ethernet_arp_ip4_entry_t * e)
-{
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-
-  arp_adj_fib_remove
-    (e, ip4_fib_table_get_index_for_sw_if_index (e->sw_if_index));
-  hash_unset (eai->arp_entries, e->ip4_address.as_u32);
-  pool_put (am->ip4_entry_pool, e);
-}
-
-static inline int
-vnet_arp_unset_ip4_over_ethernet_internal (vnet_main_t * vnm,
-					   vnet_arp_set_ip4_over_ethernet_rpc_args_t
-					   * args)
-{
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-  ethernet_arp_ip4_entry_t *e;
-  ethernet_arp_interface_t *eai;
-
-  if (vec_len (am->ethernet_arp_by_sw_if_index) <= args->sw_if_index)
-    return 0;
-
-  eai = &am->ethernet_arp_by_sw_if_index[args->sw_if_index];
-
-  e = arp_entry_find (eai, &args->ip4);
-
-  if (NULL != e)
-    {
-      adj_nbr_walk_nh4 (e->sw_if_index,
-			&e->ip4_address, arp_mk_incomplete_walk, e);
-      arp_entry_free (eai, e);
-    }
-
-  return 0;
-}
-
-
-static int
-vnet_arp_populate_ip4_over_ethernet_internal (vnet_main_t * vnm,
-					      vnet_arp_set_ip4_over_ethernet_rpc_args_t
-					      * args)
-{
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-  ethernet_arp_ip4_entry_t *e;
-  ethernet_arp_interface_t *eai;
-
-  arp_enable (am, args->sw_if_index);
-  eai = &am->ethernet_arp_by_sw_if_index[args->sw_if_index];
-
-  e = arp_entry_find (eai, &args->ip4);
-
-  if (NULL != e)
-    {
-      adj_nbr_walk_nh4 (e->sw_if_index,
-			&e->ip4_address, arp_mk_complete_walk, e);
-    }
-  return (0);
-}
-
-static void
-set_ip4_over_ethernet_rpc_callback (vnet_arp_set_ip4_over_ethernet_rpc_args_t
-				    * a)
-{
-  vnet_main_t *vm = vnet_get_main ();
-  ASSERT (vlib_get_thread_index () == 0);
-
-  if (a->flags & ETHERNET_ARP_ARGS_REMOVE)
-    vnet_arp_unset_ip4_over_ethernet_internal (vm, a);
-  else if (a->flags & ETHERNET_ARP_ARGS_FLUSH)
-    vnet_arp_flush_ip4_over_ethernet_internal (vm, a);
-  else if (a->flags & ETHERNET_ARP_ARGS_POPULATE)
-    vnet_arp_populate_ip4_over_ethernet_internal (vm, a);
-  else if (a->flags & ETHERNET_ARP_ARGS_WC_PUB)
-    vnet_arp_wc_publish_internal (vm, a);
-  else
-    vnet_arp_set_ip4_over_ethernet_internal (vm, a);
-}
-
-/**
- * @brief Invoked when the interface's admin state changes
- */
-static clib_error_t *
-ethernet_arp_sw_interface_up_down (vnet_main_t * vnm,
-				   u32 sw_if_index, u32 flags)
-{
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-  ethernet_arp_ip4_entry_t *e;
-  u32 i, *to_update = 0;
-
-  /* *INDENT-OFF* */
-  pool_foreach (e, am->ip4_entry_pool,
-  ({
-    if (e->sw_if_index == sw_if_index)
-      vec_add1 (to_update,
-		e - am->ip4_entry_pool);
-  }));
-  /* *INDENT-ON* */
-
-  for (i = 0; i < vec_len (to_update); i++)
-    {
-      e = pool_elt_at_index (am->ip4_entry_pool, to_update[i]);
-
-      vnet_arp_set_ip4_over_ethernet_rpc_args_t update_me = {
-	.ip4.as_u32 = e->ip4_address.as_u32,
-	.sw_if_index = e->sw_if_index,
-      };
-      mac_address_copy (&update_me.mac, &e->mac);
-
-      if (flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP)
-	{
-	  update_me.flags = ETHERNET_ARP_ARGS_POPULATE;
-	  vnet_arp_populate_ip4_over_ethernet_internal (vnm, &update_me);
-	}
-      else
-	{
-	  update_me.flags = ETHERNET_ARP_ARGS_FLUSH;
-	  vnet_arp_flush_ip4_over_ethernet_internal (vnm, &update_me);
-	}
-    }
-  vec_free (to_update);
-
-  return 0;
-}
-
-VNET_SW_INTERFACE_ADMIN_UP_DOWN_FUNCTION (ethernet_arp_sw_interface_up_down);
-
-static void
-increment_ip4_and_mac_address (ethernet_arp_ip4_over_ethernet_address_t * a)
-{
-  u8 old;
-  int i;
-
-  for (i = 3; i >= 0; i--)
-    {
-      old = a->ip4.as_u8[i];
-      a->ip4.as_u8[i] += 1;
-      if (old < a->ip4.as_u8[i])
-	break;
-    }
-
-  for (i = 5; i >= 0; i--)
-    {
-      old = a->mac.bytes[i];
-      a->mac.bytes[i] += 1;
-      if (old < a->mac.bytes[i])
-	break;
-    }
-}
-
-int
-vnet_arp_set_ip4_over_ethernet (vnet_main_t * vnm,
-				u32 sw_if_index,
-				const ethernet_arp_ip4_over_ethernet_address_t
-				* a, ip_neighbor_flags_t flags)
-{
-  vnet_arp_set_ip4_over_ethernet_rpc_args_t args = {
-    .sw_if_index = sw_if_index,
-    .nbr_flags = flags,
-    .flags = 0,
-    .ip4.as_u32 = a->ip4.as_u32,
-    .mac = a->mac,
-  };
-
-  vl_api_rpc_call_main_thread (set_ip4_over_ethernet_rpc_callback,
-			       (u8 *) & args, sizeof (args));
-  return 0;
-}
-
-void
-proxy_arp_walk (proxy_arp_walk_t cb, void *data)
-{
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-  ethernet_proxy_arp_t *pa;
-
-  vec_foreach (pa, am->proxy_arps)
-  {
-    if (!cb (&pa->lo_addr, &pa->hi_addr, pa->fib_index, data))
-      break;
-  }
-}
-
-int
-vnet_proxy_arp_enable_disable (vnet_main_t * vnm, u32 sw_if_index, u8 enable)
-{
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-  ethernet_arp_interface_t *eai;
-
-  vec_validate (am->ethernet_arp_by_sw_if_index, sw_if_index);
-
-  eai = &am->ethernet_arp_by_sw_if_index[sw_if_index];
-
-  if (enable)
-    {
-      if (!eai->proxy_enabled)
-	{
-	  vnet_feature_enable_disable ("arp", "arp-proxy",
-				       sw_if_index, 1, NULL, 0);
-	}
-      eai->proxy_enabled = 1;
-    }
-  else
-    {
-      if (eai->proxy_enabled)
-	{
-	  vnet_feature_enable_disable ("arp", "arp-proxy",
-				       sw_if_index, 0, NULL, 0);
-	}
-      eai->proxy_enabled = 0;
-    }
-
-  return (0);
-}
-
-int
-vnet_proxy_arp_add_del (ip4_address_t * lo_addr,
-			ip4_address_t * hi_addr, u32 fib_index, int is_del)
-{
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-  ethernet_proxy_arp_t *pa;
-  u32 found_at_index = ~0;
-
-  vec_foreach (pa, am->proxy_arps)
-  {
-    if (pa->lo_addr.as_u32 == lo_addr->as_u32 &&
-	pa->hi_addr.as_u32 == hi_addr->as_u32 && pa->fib_index == fib_index)
-      {
-	found_at_index = pa - am->proxy_arps;
-	break;
-      }
-  }
-
-  if (found_at_index != ~0)
-    {
-      /* Delete, otherwise it's already in the table */
-      if (is_del)
-	vec_delete (am->proxy_arps, 1, found_at_index);
-      return 0;
-    }
-  /* delete, no such entry */
-  if (is_del)
-    return VNET_API_ERROR_NO_SUCH_ENTRY;
-
-  /* add, not in table */
-  vec_add2 (am->proxy_arps, pa, 1);
-  pa->lo_addr.as_u32 = lo_addr->as_u32;
-  pa->hi_addr.as_u32 = hi_addr->as_u32;
-  pa->fib_index = fib_index;
-  return 0;
-}
-
-void
-proxy_arp_intfc_walk (proxy_arp_intf_walk_t cb, void *data)
-{
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-  ethernet_arp_interface_t *eai;
-
-  vec_foreach (eai, am->ethernet_arp_by_sw_if_index)
-  {
-    if (eai->proxy_enabled)
-      cb (eai - am->ethernet_arp_by_sw_if_index, data);
-  }
-}
-
-static clib_error_t *
-ip_arp_add_del_command_fn (vlib_main_t * vm,
-			   unformat_input_t * input, vlib_cli_command_t * cmd)
-{
-  vnet_main_t *vnm = vnet_get_main ();
-  u32 sw_if_index;
-  ethernet_arp_ip4_over_ethernet_address_t lo_addr, hi_addr, addr;
-  int addr_valid = 0;
-  int is_del = 0;
-  int count = 1;
-  u32 fib_index = 0;
-  u32 fib_id;
-  int is_proxy = 0;
-  ip_neighbor_flags_t flags;
-
-  flags = IP_NEIGHBOR_FLAG_NONE;
-
-  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
-    {
-      /* set ip arp TenGigE1/1/0/1 1.2.3.4 aa:bb:... or aabb.ccdd... */
-      if (unformat (input, "%U %U %U",
-		    unformat_vnet_sw_interface, vnm, &sw_if_index,
-		    unformat_ip4_address, &addr.ip4,
-		    unformat_mac_address_t, &addr.mac))
-	addr_valid = 1;
-
-      else if (unformat (input, "delete") || unformat (input, "del"))
-	is_del = 1;
-
-      else if (unformat (input, "static"))
-	flags |= IP_NEIGHBOR_FLAG_STATIC;
-
-      else if (unformat (input, "no-fib-entry"))
-	flags |= IP_NEIGHBOR_FLAG_NO_FIB_ENTRY;
-
-      else if (unformat (input, "count %d", &count))
-	;
-
-      else if (unformat (input, "fib-id %d", &fib_id))
-	{
-	  fib_index = fib_table_find (FIB_PROTOCOL_IP4, fib_id);
-
-	  if (~0 == fib_index)
-	    return clib_error_return (0, "fib ID %d doesn't exist\n", fib_id);
-	}
-
-      else if (unformat (input, "proxy %U - %U",
-			 unformat_ip4_address, &lo_addr.ip4,
-			 unformat_ip4_address, &hi_addr.ip4))
-	is_proxy = 1;
-      else
-	break;
-    }
-
-  if (is_proxy)
-    {
-      (void) vnet_proxy_arp_add_del (&lo_addr.ip4, &hi_addr.ip4,
-				     fib_index, is_del);
-      return 0;
-    }
-
-  if (addr_valid)
-    {
-      int i;
-
-      for (i = 0; i < count; i++)
-	{
-	  if (is_del == 0)
-	    {
-	      uword event_type, *event_data = 0;
-
-	      /* Park the debug CLI until the arp entry is installed */
-	      vnet_register_ip4_arp_resolution_event
-		(vnm, &addr.ip4, vlib_current_process (vm),
-		 1 /* type */ , 0 /* data */ );
-
-	      vnet_arp_set_ip4_over_ethernet (vnm, sw_if_index, &addr, flags);
-
-	      vlib_process_wait_for_event (vm);
-	      event_type = vlib_process_get_events (vm, &event_data);
-	      vec_reset_length (event_data);
-	      if (event_type != 1)
-		clib_warning ("event type %d unexpected", event_type);
-	    }
-	  else
-	    vnet_arp_unset_ip4_over_ethernet (vnm, sw_if_index, &addr);
-
-	  increment_ip4_and_mac_address (&addr);
-	}
-    }
-  else
-    {
-      return clib_error_return (0, "unknown input `%U'",
-				format_unformat_error, input);
-    }
-
-  return 0;
-}
-
-/* *INDENT-OFF* */
-/*?
- * Add or delete IPv4 ARP cache entries.
- *
- * @note 'set ip arp' options (e.g. delete, static, 'fib-id <id>',
- * 'count <number>', 'interface ip4_addr mac_addr') can be added in
- * any order and combination.
- *
- * @cliexpar
- * @parblock
- * Add or delete IPv4 ARP cache entries as follows. MAC Address can be in
- * either aa:bb:cc:dd:ee:ff format or aabb.ccdd.eeff format.
- * @cliexcmd{set ip arp GigabitEthernet2/0/0 6.0.0.3 dead.beef.babe}
- * @cliexcmd{set ip arp delete GigabitEthernet2/0/0 6.0.0.3 de:ad:be:ef:ba:be}
- *
- * To add or delete an IPv4 ARP cache entry to or from a specific fib
- * table:
- * @cliexcmd{set ip arp fib-id 1 GigabitEthernet2/0/0 6.0.0.3 dead.beef.babe}
- * @cliexcmd{set ip arp fib-id 1 delete GigabitEthernet2/0/0 6.0.0.3 dead.beef.babe}
- *
- * Add or delete IPv4 static ARP cache entries as follows:
- * @cliexcmd{set ip arp static GigabitEthernet2/0/0 6.0.0.3 dead.beef.babe}
- * @cliexcmd{set ip arp static delete GigabitEthernet2/0/0 6.0.0.3 dead.beef.babe}
- *
- * For testing / debugging purposes, the 'set ip arp' command can add or
- * delete multiple entries. Supply the 'count N' parameter:
- * @cliexcmd{set ip arp count 10 GigabitEthernet2/0/0 6.0.0.3 dead.beef.babe}
- * @endparblock
- ?*/
-VLIB_CLI_COMMAND (ip_arp_add_del_command, static) = {
-  .path = "set ip arp",
-  .short_help =
-  "set ip arp [del] <intfc> <ip-address> <mac-address> [static] [no-fib-entry] [count <count>] [fib-id <fib-id>] [proxy <lo-addr> - <hi-addr>]",
-  .function = ip_arp_add_del_command_fn,
-};
-/* *INDENT-ON* */
-
-static clib_error_t *
-set_int_proxy_arp_command_fn (vlib_main_t * vm,
-			      unformat_input_t *
-			      input, vlib_cli_command_t * cmd)
-{
-  vnet_main_t *vnm = vnet_get_main ();
-  u32 sw_if_index;
-  int enable = 0;
-
-  sw_if_index = ~0;
-
-  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
-    {
-      if (unformat (input, "%U", unformat_vnet_sw_interface,
-		    vnm, &sw_if_index))
-	;
-      else if (unformat (input, "enable") || unformat (input, "on"))
-	enable = 1;
-      else if (unformat (input, "disable") || unformat (input, "off"))
-	enable = 0;
-      else
-	break;
-    }
-
-  if (~0 == sw_if_index)
-    return clib_error_return (0, "unknown input '%U'",
-			      format_unformat_error, input);
-
-  vnet_proxy_arp_enable_disable (vnm, sw_if_index, enable);
-
-  return 0;
-}
-
-/* *INDENT-OFF* */
-/*?
- * Enable proxy-arp on an interface. The vpp stack will answer ARP
- * requests for the indicated address range. Multiple proxy-arp
- * ranges may be provisioned.
- *
- * @note Proxy ARP as a technology is infamous for blackholing traffic.
- * Also, the underlying implementation has not been performance-tuned.
- * Avoid creating an unnecessarily large set of ranges.
- *
- * @cliexpar
- * To enable proxy arp on a range of addresses, use:
- * @cliexcmd{set ip arp proxy 6.0.0.1 - 6.0.0.11}
- * Append 'del' to delete a range of proxy ARP addresses:
- * @cliexcmd{set ip arp proxy 6.0.0.1 - 6.0.0.11 del}
- * You must then specifically enable proxy arp on individual interfaces:
- * @cliexcmd{set interface proxy-arp GigabitEthernet0/8/0 enable}
- * To disable proxy arp on an individual interface:
- * @cliexcmd{set interface proxy-arp GigabitEthernet0/8/0 disable}
- ?*/
-VLIB_CLI_COMMAND (set_int_proxy_enable_command, static) = {
-  .path = "set interface proxy-arp",
-  .short_help =
-  "set interface proxy-arp <intfc> [enable|disable]",
-  .function = set_int_proxy_arp_command_fn,
-};
-/* *INDENT-ON* */
-
-
-/*
- * ARP/ND Termination in a L2 Bridge Domain based on IP4/IP6 to MAC
- * hash tables mac_by_ip4 and mac_by_ip6 for each BD.
- */
-typedef enum
-{
-  ARP_TERM_NEXT_L2_OUTPUT,
-  ARP_TERM_NEXT_DROP,
-  ARP_TERM_N_NEXT,
-} arp_term_next_t;
-
-u32 arp_term_next_node_index[32];
-
-static uword
-arp_term_l2bd (vlib_main_t * vm,
-	       vlib_node_runtime_t * node, vlib_frame_t * frame)
-{
-  l2input_main_t *l2im = &l2input_main;
-  u32 n_left_from, next_index, *from, *to_next;
-  u32 n_replies_sent = 0;
-  u16 last_bd_index = ~0;
-  l2_bridge_domain_t *last_bd_config = 0;
-  l2_input_config_t *cfg0;
-
-  from = vlib_frame_vector_args (frame);
-  n_left_from = frame->n_vectors;
-  next_index = node->cached_next_index;
-
-  while (n_left_from > 0)
-    {
-      u32 n_left_to_next;
-
-      vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
-
-      while (n_left_from > 0 && n_left_to_next > 0)
-	{
-	  vlib_buffer_t *p0;
-	  ethernet_header_t *eth0;
-	  ethernet_arp_header_t *arp0;
-	  ip6_header_t *iph0;
-	  u8 *l3h0;
-	  u32 pi0, error0, next0, sw_if_index0;
-	  u16 ethertype0;
-	  u16 bd_index0;
-	  u32 ip0;
-	  u8 *macp0;
-
-	  pi0 = from[0];
-	  to_next[0] = pi0;
-	  from += 1;
-	  to_next += 1;
-	  n_left_from -= 1;
-	  n_left_to_next -= 1;
-
-	  p0 = vlib_get_buffer (vm, pi0);
-	  // Terminate only local (SHG == 0) ARP
-	  if (vnet_buffer (p0)->l2.shg != 0)
-	    goto next_l2_feature;
-
-	  eth0 = vlib_buffer_get_current (p0);
-	  l3h0 = (u8 *) eth0 + vnet_buffer (p0)->l2.l2_len;
-	  ethertype0 = clib_net_to_host_u16 (*(u16 *) (l3h0 - 2));
-	  arp0 = (ethernet_arp_header_t *) l3h0;
-
-	  if (ethertype0 != ETHERNET_TYPE_ARP)
-	    goto check_ip6_nd;
-
-	  if ((arp0->opcode !=
-	       clib_host_to_net_u16 (ETHERNET_ARP_OPCODE_request)) &&
-	      (arp0->opcode !=
-	       clib_host_to_net_u16 (ETHERNET_ARP_OPCODE_reply)))
-	    goto check_ip6_nd;
-
-	  /* Must be ARP request/reply packet here */
-	  if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE) &&
-			     (p0->flags & VLIB_BUFFER_IS_TRACED)))
-	    {
-	      u8 *t0 = vlib_add_trace (vm, node, p0,
-				       sizeof (ethernet_arp_input_trace_t));
-	      clib_memcpy_fast (t0, l3h0,
-				sizeof (ethernet_arp_input_trace_t));
-	    }
-
-	  error0 = 0;
-	  error0 =
-	    (arp0->l2_type !=
-	     clib_net_to_host_u16 (ETHERNET_ARP_HARDWARE_TYPE_ethernet)
-	     ? ETHERNET_ARP_ERROR_l2_type_not_ethernet : error0);
-	  error0 =
-	    (arp0->l3_type !=
-	     clib_net_to_host_u16 (ETHERNET_TYPE_IP4) ?
-	     ETHERNET_ARP_ERROR_l3_type_not_ip4 : error0);
-
-	  sw_if_index0 = vnet_buffer (p0)->sw_if_index[VLIB_RX];
-
-	  if (error0)
-	    goto drop;
-
-	  /* Trash ARP packets whose ARP-level source addresses do not
-	     match, or if requester address is mcast */
-	  if (PREDICT_FALSE
-	      (!ethernet_mac_address_equal (eth0->src_address,
-					    arp0->ip4_over_ethernet[0].
-					    mac.bytes))
-	      || ethernet_address_cast (arp0->ip4_over_ethernet[0].mac.bytes))
-	    {
-	      /* VRRP virtual MAC may be different to SMAC in ARP reply */
-	      if (!ethernet_mac_address_equal
-		  (arp0->ip4_over_ethernet[0].mac.bytes, vrrp_prefix))
-		{
-		  error0 = ETHERNET_ARP_ERROR_l2_address_mismatch;
-		  goto drop;
-		}
-	    }
-	  if (PREDICT_FALSE
-	      (ip4_address_is_multicast (&arp0->ip4_over_ethernet[0].ip4)))
-	    {
-	      error0 = ETHERNET_ARP_ERROR_l3_src_address_not_local;
-	      goto drop;
-	    }
-
-	  /* Check if anyone want ARP request events for L2 BDs */
-	  {
-	    ethernet_arp_main_t *am = &ethernet_arp_main;
-	    if (am->wc_ip4_arp_publisher_node != (uword) ~ 0)
-	      vnet_arp_wc_publish (sw_if_index0, &arp0->ip4_over_ethernet[0]);
-	  }
-
-	  /* lookup BD mac_by_ip4 hash table for MAC entry */
-	  ip0 = arp0->ip4_over_ethernet[1].ip4.as_u32;
-	  bd_index0 = vnet_buffer (p0)->l2.bd_index;
-	  if (PREDICT_FALSE ((bd_index0 != last_bd_index)
-			     || (last_bd_index == (u16) ~ 0)))
-	    {
-	      last_bd_index = bd_index0;
-	      last_bd_config = vec_elt_at_index (l2im->bd_configs, bd_index0);
-	    }
-	  macp0 = (u8 *) hash_get (last_bd_config->mac_by_ip4, ip0);
-
-	  if (PREDICT_FALSE (!macp0))
-	    goto next_l2_feature;	/* MAC not found */
-	  if (PREDICT_FALSE (arp0->ip4_over_ethernet[0].ip4.as_u32 ==
-			     arp0->ip4_over_ethernet[1].ip4.as_u32))
-	    goto next_l2_feature;	/* GARP */
-
-	  /* MAC found, send ARP reply -
-	     Convert ARP request packet to ARP reply */
-	  arp0->opcode = clib_host_to_net_u16 (ETHERNET_ARP_OPCODE_reply);
-	  arp0->ip4_over_ethernet[1] = arp0->ip4_over_ethernet[0];
-	  arp0->ip4_over_ethernet[0].ip4.as_u32 = ip0;
-	  mac_address_from_bytes (&arp0->ip4_over_ethernet[0].mac, macp0);
-	  clib_memcpy_fast (eth0->dst_address, eth0->src_address, 6);
-	  clib_memcpy_fast (eth0->src_address, macp0, 6);
-	  n_replies_sent += 1;
-
-	output_response:
-	  /* For BVI, need to use l2-fwd node to send ARP reply as
-	     l2-output node cannot output packet to BVI properly */
-	  cfg0 = vec_elt_at_index (l2im->configs, sw_if_index0);
-	  if (PREDICT_FALSE (cfg0->bvi))
-	    {
-	      vnet_buffer (p0)->l2.feature_bitmap |= L2INPUT_FEAT_FWD;
-	      vnet_buffer (p0)->sw_if_index[VLIB_RX] = 0;
-	      goto next_l2_feature;
-	    }
-
-	  /* Send ARP/ND reply back out input interface through l2-output */
-	  vnet_buffer (p0)->sw_if_index[VLIB_TX] = sw_if_index0;
-	  next0 = ARP_TERM_NEXT_L2_OUTPUT;
-	  vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
-					   to_next, n_left_to_next, pi0,
-					   next0);
-	  continue;
-
-	check_ip6_nd:
-	  /* IP6 ND event notification or solicitation handling to generate
-	     local response instead of flooding */
-	  iph0 = (ip6_header_t *) l3h0;
-	  if (PREDICT_FALSE (ethertype0 == ETHERNET_TYPE_IP6 &&
-			     iph0->protocol == IP_PROTOCOL_ICMP6 &&
-			     !ip6_address_is_unspecified
-			     (&iph0->src_address)))
-	    {
-	      sw_if_index0 = vnet_buffer (p0)->sw_if_index[VLIB_RX];
-	      if (vnet_ip6_nd_term
-		  (vm, node, p0, eth0, iph0, sw_if_index0,
-		   vnet_buffer (p0)->l2.bd_index))
-		goto output_response;
-	    }
-
-	next_l2_feature:
-	  {
-	    next0 = vnet_l2_feature_next (p0, arp_term_next_node_index,
-					  L2INPUT_FEAT_ARP_TERM);
-	    vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
-					     to_next, n_left_to_next,
-					     pi0, next0);
-	    continue;
-	  }
-
-	drop:
-	  if (0 == arp0->ip4_over_ethernet[0].ip4.as_u32 ||
-	      (arp0->ip4_over_ethernet[0].ip4.as_u32 ==
-	       arp0->ip4_over_ethernet[1].ip4.as_u32))
-	    {
-	      error0 = ETHERNET_ARP_ERROR_gratuitous_arp;
-	    }
-	  next0 = ARP_TERM_NEXT_DROP;
-	  p0->error = node->errors[error0];
-
-	  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);
-    }
-
-  vlib_error_count (vm, node->node_index,
-		    ETHERNET_ARP_ERROR_replies_sent, n_replies_sent);
-  return frame->n_vectors;
-}
-
-/* *INDENT-OFF* */
-VLIB_REGISTER_NODE (arp_term_l2bd_node, static) = {
-  .function = arp_term_l2bd,
-  .name = "arp-term-l2bd",
-  .vector_size = sizeof (u32),
-  .n_errors = ETHERNET_ARP_N_ERROR,
-  .error_strings = ethernet_arp_error_strings,
-  .n_next_nodes = ARP_TERM_N_NEXT,
-  .next_nodes = {
-    [ARP_TERM_NEXT_L2_OUTPUT] = "l2-output",
-    [ARP_TERM_NEXT_DROP] = "error-drop",
-  },
-  .format_buffer = format_ethernet_arp_header,
-  .format_trace = format_arp_term_input_trace,
-};
-/* *INDENT-ON* */
-
-clib_error_t *
-arp_term_init (vlib_main_t * vm)
-{
-  // Initialize the feature next-node indexes
-  feat_bitmap_init_next_nodes (vm,
-			       arp_term_l2bd_node.index,
-			       L2INPUT_N_FEAT,
-			       l2input_get_feat_names (),
-			       arp_term_next_node_index);
-  return 0;
-}
-
-VLIB_INIT_FUNCTION (arp_term_init);
-
-void
-change_arp_mac (u32 sw_if_index, ethernet_arp_ip4_entry_t * e)
-{
-  if (e->sw_if_index == sw_if_index)
-    {
-      adj_nbr_walk_nh4 (e->sw_if_index,
-			&e->ip4_address, arp_mk_complete_walk, e);
-    }
-}
-
-void
-ethernet_arp_change_mac (u32 sw_if_index)
-{
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-  ethernet_arp_ip4_entry_t *e;
-  adj_index_t ai;
-
-  /* *INDENT-OFF* */
-  pool_foreach (e, am->ip4_entry_pool,
-  ({
-    change_arp_mac (sw_if_index, e);
-  }));
-  /* *INDENT-ON* */
-
-  ai = adj_glean_get (FIB_PROTOCOL_IP4, sw_if_index);
-
-  if (ADJ_INDEX_INVALID != ai)
-    adj_glean_update_rewrite (ai);
-}
-
-void
-send_ip4_garp (vlib_main_t * vm, u32 sw_if_index)
-{
-  ip4_main_t *i4m = &ip4_main;
-  ip4_address_t *ip4_addr = ip4_interface_first_address (i4m, sw_if_index, 0);
-
-  send_ip4_garp_w_addr (vm, ip4_addr, sw_if_index);
-}
-
-void
-send_ip4_garp_w_addr (vlib_main_t * vm,
-		      const ip4_address_t * ip4_addr, u32 sw_if_index)
-{
-  ip4_main_t *i4m = &ip4_main;
-  vnet_main_t *vnm = vnet_get_main ();
-  u8 *rewrite, rewrite_len;
-  vnet_hw_interface_t *hi = vnet_get_sup_hw_interface (vnm, sw_if_index);
-
-  if (ip4_addr)
-    {
-      clib_warning ("Sending GARP for IP4 address %U on sw_if_idex %d",
-		    format_ip4_address, ip4_addr, sw_if_index);
-
-      /* Form GARP packet for output - Gratuitous ARP is an ARP request packet
-         where the interface IP/MAC pair is used for both source and request
-         MAC/IP pairs in the request */
-      u32 bi = 0;
-      ethernet_arp_header_t *h = vlib_packet_template_get_packet
-	(vm, &i4m->ip4_arp_request_packet_template, &bi);
-
-      if (!h)
-	return;
-
-      mac_address_from_bytes (&h->ip4_over_ethernet[0].mac, hi->hw_address);
-      mac_address_from_bytes (&h->ip4_over_ethernet[1].mac, hi->hw_address);
-      h->ip4_over_ethernet[0].ip4 = ip4_addr[0];
-      h->ip4_over_ethernet[1].ip4 = ip4_addr[0];
-
-      /* Setup MAC header with ARP Etype and broadcast DMAC */
-      vlib_buffer_t *b = vlib_get_buffer (vm, bi);
-      rewrite =
-	ethernet_build_rewrite (vnm, sw_if_index, VNET_LINK_ARP,
-				VNET_REWRITE_FOR_SW_INTERFACE_ADDRESS_BROADCAST);
-      rewrite_len = vec_len (rewrite);
-      vlib_buffer_advance (b, -rewrite_len);
-      ethernet_header_t *e = vlib_buffer_get_current (b);
-      clib_memcpy_fast (e->dst_address, rewrite, rewrite_len);
-      vec_free (rewrite);
-
-      /* Send GARP packet out the specified interface */
-      vnet_buffer (b)->sw_if_index[VLIB_RX] =
-	vnet_buffer (b)->sw_if_index[VLIB_TX] = sw_if_index;
-      vlib_frame_t *f = vlib_get_frame_to_node (vm, hi->output_node_index);
-      u32 *to_next = vlib_frame_vector_args (f);
-      to_next[0] = bi;
-      f->n_vectors = 1;
-      vlib_put_frame_to_node (vm, hi->output_node_index, f);
-    }
-}
-
-/*
- * Remove any arp entries associated with the specified interface
- */
-static clib_error_t *
-vnet_arp_delete_sw_interface (vnet_main_t * vnm, u32 sw_if_index, u32 is_add)
-{
-  ethernet_arp_main_t *am = &ethernet_arp_main;
-
-  if (!is_add && sw_if_index != ~0)
-    {
-      ethernet_arp_ip4_entry_t *e;
-      /* *INDENT-OFF* */
-      pool_foreach (e, am->ip4_entry_pool, ({
-        if (e->sw_if_index != sw_if_index)
-          continue;
-        vnet_arp_set_ip4_over_ethernet_rpc_args_t args = {
-          .sw_if_index = sw_if_index,
-          .ip4 = e->ip4_address,
-        };
-        vnet_arp_unset_ip4_over_ethernet_internal (vnm, &args);
-      }));
-      /* *INDENT-ON* */
-      arp_disable (am, sw_if_index);
-    }
-  else if (is_add)
-    {
-      vnet_feature_enable_disable ("arp", "arp-disabled",
-				   sw_if_index, 1, NULL, 0);
-    }
-
-  return (NULL);
-}
-
-VNET_SW_INTERFACE_ADD_DEL_FUNCTION (vnet_arp_delete_sw_interface);
-
-/*
- * fd.io coding-style-patch-verification: ON
- *
- * Local Variables:
- * eval: (c-set-style "gnu")
- * End:
- */
diff --git a/src/vnet/ethernet/arp.h b/src/vnet/ethernet/arp.h
deleted file mode 100644
index de92c4f419c..00000000000
--- a/src/vnet/ethernet/arp.h
+++ /dev/null
@@ -1,123 +0,0 @@
-/*
- * Copyright (c) 2015 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.
- */
-
-#ifndef __ARP_H__
-#define __ARP_H__
-
-#include <vnet/ethernet/ethernet.h>
-#include <vnet/ethernet/arp_packet.h>
-#include <vnet/ip/ip.h>
-#include <vnet/ip/ip_neighbor.h>
-
-typedef struct
-{
-  u32 sw_if_index;
-  ip4_address_t ip4_address;
-
-  mac_address_t mac;
-
-  ip_neighbor_flags_t flags;
-
-  f64 time_last_updated;
-
-  /**
-   * The index of the adj-fib entry created
-   */
-  fib_node_index_t fib_entry_index;
-} ethernet_arp_ip4_entry_t;
-
-extern u8 *format_ethernet_arp_ip4_entry (u8 * s, va_list * va);
-
-ethernet_arp_ip4_entry_t *ip4_neighbors_pool (void);
-ethernet_arp_ip4_entry_t *ip4_neighbor_entries (u32 sw_if_index);
-
-extern int vnet_proxy_arp_add_del (ip4_address_t * lo_addr,
-				   ip4_address_t * hi_addr,
-				   u32 fib_index, int is_del);
-
-extern int vnet_proxy_arp_enable_disable (vnet_main_t * vnm,
-					  u32 sw_if_index, u8 enable);
-
-extern int vnet_arp_set_ip4_over_ethernet (vnet_main_t * vnm,
-					   u32 sw_if_index,
-					   const
-					   ethernet_arp_ip4_over_ethernet_address_t
-					   * a, ip_neighbor_flags_t flags);
-
-extern int vnet_arp_unset_ip4_over_ethernet (vnet_main_t * vnm,
-					     u32 sw_if_index,
-					     const
-					     ethernet_arp_ip4_over_ethernet_address_t
-					     * a);
-
-void vnet_register_ip4_arp_resolution_event (vnet_main_t * vnm,
-					     void *address_arg,
-					     uword node_index,
-					     uword type_opaque, uword data);
-
-typedef int (*arp_change_event_cb_t) (u32 pool_index,
-				      const mac_address_t * mac,
-				      u32 sw_if_index,
-				      const ip4_address_t * address);
-
-int vnet_add_del_ip4_arp_change_event (vnet_main_t * vnm,
-				       arp_change_event_cb_t data_callback,
-				       u32 pid,
-				       void *address_arg,
-				       uword node_index,
-				       uword type_opaque,
-				       uword data, int is_add);
-
-void wc_arp_set_publisher_node (uword inode_index, uword event_type);
-
-void ethernet_arp_change_mac (u32 sw_if_index);
-void ethernet_ndp_change_mac (u32 sw_if_index);
-
-void arp_update_adjacency (vnet_main_t * vnm, u32 sw_if_index, u32 ai);
-
-typedef struct
-{
-  u32 sw_if_index;
-  ip4_address_t ip;
-  mac_address_t mac;
-} wc_arp_report_t;
-
-/**
- * call back function when walking the DB of proxy ARPs
- * @return 0 to stop the walk !0 to continue
- */
-typedef walk_rc_t (proxy_arp_walk_t) (const ip4_address_t * lo_addr,
-				      const ip4_address_t * hi_addr,
-				      u32 fib_index, void *dat);
-
-extern void proxy_arp_walk (proxy_arp_walk_t cb, void *data);
-
-/**
- * call back function when walking the DB of proxy ARP interface
- * @return 0 to stop the walk !0 to continue
- */
-typedef walk_rc_t (proxy_arp_intf_walk_t) (u32 sw_if_index, void *data);
-
-extern void proxy_arp_intfc_walk (proxy_arp_intf_walk_t cb, void *data);
-
-#endif
-
-/*
- * fd.io coding-style-patch-verification: ON
- *
- * Local Variables:
- * eval: (c-set-style "gnu")
- * End:
- */
diff --git a/src/vnet/ethernet/arp_packet.c b/src/vnet/ethernet/arp_packet.c
new file mode 100644
index 00000000000..c72dab99ad5
--- /dev/null
+++ b/src/vnet/ethernet/arp_packet.c
@@ -0,0 +1,111 @@
+/*
+ * ethernet/arp.c: IP v4 ARP node
+ *
+ * Copyright (c) 2010 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.
+ */
+
+#include <vnet/ethernet/arp_packet.h>
+#include <vnet/ethernet/ethernet.h>
+#include <vnet/ip/format.h>
+
+u8 *
+format_ethernet_arp_opcode (u8 * s, va_list * va)
+{
+  ethernet_arp_opcode_t o = va_arg (*va, ethernet_arp_opcode_t);
+  char *t = 0;
+  switch (o)
+    {
+#define _(f) case ETHERNET_ARP_OPCODE_##f: t = #f; break;
+      foreach_ethernet_arp_opcode;
+#undef _
+
+    default:
+      return format (s, "unknown 0x%x", o);
+    }
+
+  return format (s, "%s", t);
+}
+
+u8 *
+format_ethernet_arp_hardware_type (u8 * s, va_list * va)
+{
+  ethernet_arp_hardware_type_t h = va_arg (*va, ethernet_arp_hardware_type_t);
+  char *t = 0;
+  switch (h)
+    {
+#define _(n,f) case n: t = #f; break;
+      foreach_ethernet_arp_hardware_type;
+#undef _
+
+    default:
+      return format (s, "unknown 0x%x", h);
+    }
+
+  return format (s, "%s", t);
+}
+
+u8 *
+format_ethernet_arp_header (u8 * s, va_list * va)
+{
+  ethernet_arp_header_t *a = va_arg (*va, ethernet_arp_header_t *);
+  u32 max_header_bytes = va_arg (*va, u32);
+  u32 indent;
+  u16 l2_type, l3_type;
+
+  if (max_header_bytes != 0 && sizeof (a[0]) > max_header_bytes)
+    return format (s, "ARP header truncated");
+
+  l2_type = clib_net_to_host_u16 (a->l2_type);
+  l3_type = clib_net_to_host_u16 (a->l3_type);
+
+  indent = format_get_indent (s);
+
+  s = format (s, "%U, type %U/%U, address size %d/%d",
+	      format_ethernet_arp_opcode, clib_net_to_host_u16 (a->opcode),
+	      format_ethernet_arp_hardware_type, l2_type,
+	      format_ethernet_type, l3_type,
+	      a->n_l2_address_bytes, a->n_l3_address_bytes);
+
+  if (l2_type == ETHERNET_ARP_HARDWARE_TYPE_ethernet
+      && l3_type == ETHERNET_TYPE_IP4)
+    {
+      s = format (s, "\n%U%U/%U -> %U/%U",
+		  format_white_space, indent,
+		  format_mac_address_t, &a->ip4_over_ethernet[0].mac,
+		  format_ip4_address, &a->ip4_over_ethernet[0].ip4,
+		  format_mac_address_t, &a->ip4_over_ethernet[1].mac,
+		  format_ip4_address, &a->ip4_over_ethernet[1].ip4);
+    }
+  else
+    {
+      uword n2 = a->n_l2_address_bytes;
+      uword n3 = a->n_l3_address_bytes;
+      s = format (s, "\n%U%U/%U -> %U/%U",
+		  format_white_space, indent,
+		  format_hex_bytes, a->data + 0 * n2 + 0 * n3, n2,
+		  format_hex_bytes, a->data + 1 * n2 + 0 * n3, n3,
+		  format_hex_bytes, a->data + 1 * n2 + 1 * n3, n2,
+		  format_hex_bytes, a->data + 2 * n2 + 1 * n3, n3);
+    }
+
+  return s;
+}
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/vnet/ethernet/arp_packet.h b/src/vnet/ethernet/arp_packet.h
index b4e021cce19..a35adf17c85 100644
--- a/src/vnet/ethernet/arp_packet.h
+++ b/src/vnet/ethernet/arp_packet.h
@@ -18,6 +18,7 @@
 #ifndef included_ethernet_arp_packet_h
 #define included_ethernet_arp_packet_h
 
+#include <vnet/ip/ip4_packet.h>
 #include <vnet/ethernet/mac_address.h>
 
 #define foreach_ethernet_arp_hardware_type	\
@@ -145,9 +146,9 @@ typedef struct
   };
 } ethernet_arp_header_t;
 
-void send_ip4_garp (vlib_main_t * vm, u32 sw_if_index);
-void send_ip4_garp_w_addr (vlib_main_t * vm,
-			   const ip4_address_t * ip4_addr, u32 sw_if_index);
+extern u8 *format_ethernet_arp_header (u8 * s, va_list * va);
+extern u8 *format_ethernet_arp_opcode (u8 * s, va_list * va);
+extern u8 *format_ethernet_arp_hardware_type (u8 * s, va_list * va);
 
 #endif /* included_ethernet_arp_packet_h */
 
diff --git a/src/vnet/ethernet/ethernet.h b/src/vnet/ethernet/ethernet.h
index cde6fb90038..2e5209c4423 100644
--- a/src/vnet/ethernet/ethernet.h
+++ b/src/vnet/ethernet/ethernet.h
@@ -257,8 +257,19 @@ typedef struct
   u32 input_next_mpls;
 } next_by_ethertype_t;
 
+struct ethernet_main_t_;
+
+typedef void (ethernet_address_change_function_t)
+  (struct ethernet_main_t_ * im, u32 sw_if_index, uword opaque);
+
 typedef struct
 {
+  ethernet_address_change_function_t *function;
+  uword function_opaque;
+} ethernet_address_change_ctx_t;
+
+typedef struct ethernet_main_t_
+{
   vlib_main_t *vlib_main;
 
   /* next node index for the L3 input node of each ethertype */
@@ -300,6 +311,10 @@ typedef struct
 
   /* Allocated loopback instances */
   uword *bm_loopback_instances;
+
+  /** Functions to call when interface hw address changes. */
+  ethernet_address_change_ctx_t *address_change_callbacks;
+
 } ethernet_main_t;
 
 extern ethernet_main_t ethernet_main;
@@ -552,8 +567,6 @@ void ethernet_update_adjacency (vnet_main_t * vnm, u32 sw_if_index, u32 ai);
 u8 *ethernet_build_rewrite (vnet_main_t * vnm,
 			    u32 sw_if_index,
 			    vnet_link_t link_type, const void *dst_address);
-const u8 *ethernet_ip4_mcast_dst_addr (void);
-const u8 *ethernet_ip6_mcast_dst_addr (void);
 void ethernet_input_init (vlib_main_t * vm, ethernet_main_t * em);
 
 extern vlib_node_registration_t ethernet_input_node;
diff --git a/src/vnet/ethernet/interface.c b/src/vnet/ethernet/interface.c
index d79669206a9..39e5cfb3cf8 100644
--- a/src/vnet/ethernet/interface.c
+++ b/src/vnet/ethernet/interface.c
@@ -41,10 +41,12 @@
 #include <vnet/ip/ip.h>
 #include <vnet/pg/pg.h>
 #include <vnet/ethernet/ethernet.h>
-#include <vnet/ethernet/arp.h>
+//#include <vnet/ethernet/arp.h>
 #include <vnet/l2/l2_input.h>
 #include <vnet/l2/l2_bd.h>
 #include <vnet/adj/adj.h>
+#include <vnet/adj/adj_mcast.h>
+#include <vnet/ip-neighbor/ip_neighbor.h>
 
 /**
  * @file
@@ -53,7 +55,7 @@
  * This file contains code to manage loopback interfaces.
  */
 
-const u8 *
+static const u8 *
 ethernet_ip4_mcast_dst_addr (void)
 {
   const static u8 ethernet_mcast_dst_mac[] = {
@@ -63,7 +65,7 @@ ethernet_ip4_mcast_dst_addr (void)
   return (ethernet_mcast_dst_mac);
 }
 
-const u8 *
+static const u8 *
 ethernet_ip6_mcast_dst_addr (void)
 {
   const static u8 ethernet_mcast_dst_mac[] = {
@@ -195,27 +197,74 @@ ethernet_build_rewrite (vnet_main_t * vnm,
 void
 ethernet_update_adjacency (vnet_main_t * vnm, u32 sw_if_index, u32 ai)
 {
-  ip_adjacency_t *adj;
-
-  adj = adj_get (ai);
-
   vnet_sw_interface_t *si = vnet_get_sw_interface (vnm, sw_if_index);
+
   if ((si->type == VNET_SW_INTERFACE_TYPE_P2P) ||
       (si->type == VNET_SW_INTERFACE_TYPE_PIPE))
     {
       default_update_adjacency (vnm, sw_if_index, ai);
     }
-  else if (FIB_PROTOCOL_IP4 == adj->ia_nh_proto)
-    {
-      arp_update_adjacency (vnm, sw_if_index, ai);
-    }
-  else if (FIB_PROTOCOL_IP6 == adj->ia_nh_proto)
-    {
-      ip6_ethernet_update_adjacency (vnm, sw_if_index, ai);
-    }
   else
     {
-      ASSERT (0);
+      ip_adjacency_t *adj;
+
+      adj = adj_get (ai);
+
+      switch (adj->lookup_next_index)
+	{
+	case IP_LOOKUP_NEXT_GLEAN:
+	  adj_glean_update_rewrite (ai);
+	  break;
+	case IP_LOOKUP_NEXT_ARP:
+	  ip_neighbor_update (vnm, ai);
+	  break;
+	case IP_LOOKUP_NEXT_BCAST:
+	  adj_nbr_update_rewrite (ai,
+				  ADJ_NBR_REWRITE_FLAG_COMPLETE,
+				  ethernet_build_rewrite
+				  (vnm,
+				   adj->rewrite_header.sw_if_index,
+				   adj->ia_link,
+				   VNET_REWRITE_FOR_SW_INTERFACE_ADDRESS_BROADCAST));
+	  break;
+	case IP_LOOKUP_NEXT_MCAST:
+	  {
+	    /*
+	     * Construct a partial rewrite from the known ethernet mcast dest MAC
+	     */
+	    u8 *rewrite;
+	    u8 offset;
+
+	    rewrite = ethernet_build_rewrite
+	      (vnm,
+	       sw_if_index,
+	       adj->ia_link,
+	       (adj->ia_nh_proto == FIB_PROTOCOL_IP6 ?
+		ethernet_ip6_mcast_dst_addr () :
+		ethernet_ip4_mcast_dst_addr ()));
+
+	    /*
+	     * Complete the remaining fields of the adj's rewrite to direct the
+	     * complete of the rewrite at switch time by copying in the IP
+	     * dst address's bytes.
+	     * Ofset is 2 bytes into the destintation address.
+	     */
+	    offset = vec_len (rewrite) - 2;
+	    adj_mcast_update_rewrite (ai, rewrite, offset);
+
+	    break;
+	  }
+	case IP_LOOKUP_NEXT_DROP:
+	case IP_LOOKUP_NEXT_PUNT:
+	case IP_LOOKUP_NEXT_LOCAL:
+	case IP_LOOKUP_NEXT_REWRITE:
+	case IP_LOOKUP_NEXT_MCAST_MIDCHAIN:
+	case IP_LOOKUP_NEXT_MIDCHAIN:
+	case IP_LOOKUP_NEXT_ICMP_ERROR:
+	case IP_LOOKUP_N_NEXT:
+	  ASSERT (0);
+	  break;
+	}
     }
 }
 
@@ -234,8 +283,12 @@ ethernet_mac_change (vnet_hw_interface_t * hi,
   clib_memcpy (hi->hw_address, mac_address, vec_len (hi->hw_address));
 
   clib_memcpy (ei->address, (u8 *) mac_address, sizeof (ei->address));
-  ethernet_arp_change_mac (hi->sw_if_index);
-  ethernet_ndp_change_mac (hi->sw_if_index);
+
+  {
+    ethernet_address_change_ctx_t *cb;
+    vec_foreach (cb, em->address_change_callbacks)
+      cb->function (em, hi->sw_if_index, cb->function_opaque);
+  }
 
   return (NULL);
 }
diff --git a/src/vnet/ethernet/mac_address.c b/src/vnet/ethernet/mac_address.c
index 6f40e50efa2..b7981299700 100644
--- a/src/vnet/ethernet/mac_address.c
+++ b/src/vnet/ethernet/mac_address.c
@@ -61,6 +61,16 @@ unformat_mac_address_t (unformat_input_t * input, va_list * args)
   return (0);
 }
 
+void
+mac_address_increment (mac_address_t * mac)
+{
+  u64 a;
+
+  a = mac_address_as_u64 (mac);
+  a++;
+  mac_address_from_u64 (mac, a);
+}
+
 /*
  * fd.io coding-style-patch-verification: ON
  *
diff --git a/src/vnet/ethernet/mac_address.h b/src/vnet/ethernet/mac_address.h
index 01fb76e002b..aa773c5c449 100644
--- a/src/vnet/ethernet/mac_address.h
+++ b/src/vnet/ethernet/mac_address.h
@@ -149,6 +149,7 @@ mac_address_set_zero (mac_address_t * mac)
   mac->u.last_2 = 0;
 }
 
+extern void mac_address_increment (mac_address_t * mac);
 extern uword unformat_mac_address_t (unformat_input_t * input,
 				     va_list * args);
 extern u8 *format_mac_address_t (u8 * s, va_list * args);