src/vnet/ip6-nd/ip6_nd.c - fdio/vpp - Gitiles

 /*
  * ip/ip6_neighbor.c: IP6 neighbor handling
  *
  * 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/ip6-nd/ip6_nd.h>

 #include <vnet/ip-neighbor/ip_neighbor.h>
 #include <vnet/ip-neighbor/ip_neighbor_dp.h>

 #include <vnet/fib/ip6_fib.h>
 #include <vnet/ip/ip6_link.h>
 #include <vnet/ip/ip6_ll_table.h>

 /**
  * @file
  * @brief IPv6 Neighbor Adjacency and Neighbor Discovery.
  *
  * The files contains the API and CLI code for managing IPv6 neighbor
  * adjacency tables and neighbor discovery logic.
  */

 #define DEF_MAX_RADV_INTERVAL 200
 #define DEF_MIN_RADV_INTERVAL .75 * DEF_MAX_RADV_INTERVAL

 typedef struct ip6_nd_t_
 {
   /* local information */
   u32 sw_if_index;

   /* stats */
   u32 n_solicitations_rcvd;
   u32 n_solicitations_dropped;
 } ip6_nd_t;

 static ip6_link_delegate_id_t ip6_nd_delegate_id;
 static ip6_nd_t *ip6_nd_pool;


 typedef enum
 {
   ICMP6_NEIGHBOR_SOLICITATION_NEXT_DROP,
   ICMP6_NEIGHBOR_SOLICITATION_NEXT_REPLY,
   ICMP6_NEIGHBOR_SOLICITATION_N_NEXT,
 } icmp6_neighbor_solicitation_or_advertisement_next_t;

 static_always_inline uword
 icmp6_neighbor_solicitation_or_advertisement (vlib_main_t * vm,
 					      vlib_node_runtime_t * node,
 					      vlib_frame_t * frame,
 					      uword is_solicitation)
 {
   vnet_main_t *vnm = vnet_get_main ();
   ip6_main_t *im = &ip6_main;
   uword n_packets = frame->n_vectors;
   u32 *from, *to_next;
   u32 n_left_from, n_left_to_next, next_index, n_advertisements_sent;
   icmp6_neighbor_discovery_option_type_t option_type;
   vlib_node_runtime_t *error_node =
     vlib_node_get_runtime (vm, ip6_icmp_input_node.index);
   int bogus_length;

   from = vlib_frame_vector_args (frame);
   n_left_from = n_packets;
   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 (icmp6_input_trace_t));

   option_type =
     (is_solicitation
      ? ICMP6_NEIGHBOR_DISCOVERY_OPTION_source_link_layer_address
      : ICMP6_NEIGHBOR_DISCOVERY_OPTION_target_link_layer_address);
   n_advertisements_sent = 0;

   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)
 	{
 	  vlib_buffer_t *p0;
 	  ip6_header_t *ip0;
 	  icmp6_neighbor_solicitation_or_advertisement_header_t *h0;
 	  icmp6_neighbor_discovery_ethernet_link_layer_address_option_t *o0;
 	  u32 bi0, options_len0, sw_if_index0, next0, error0;
 	  u32 ip6_sadd_link_local, ip6_sadd_unspecified;
 	  int is_rewrite0;
 	  u32 ni0;

 	  bi0 = to_next[0] = from[0];

 	  from += 1;
 	  to_next += 1;
 	  n_left_from -= 1;
 	  n_left_to_next -= 1;

 	  p0 = vlib_get_buffer (vm, bi0);
 	  ip0 = vlib_buffer_get_current (p0);
 	  h0 = ip6_next_header (ip0);
 	  options_len0 =
 	    clib_net_to_host_u16 (ip0->payload_length) - sizeof (h0[0]);

 	  error0 = ICMP6_ERROR_NONE;
 	  sw_if_index0 = vnet_buffer (p0)->sw_if_index[VLIB_RX];
 	  ip6_sadd_link_local =
 	    ip6_address_is_link_local_unicast (&ip0->src_address);
 	  ip6_sadd_unspecified =
 	    ip6_address_is_unspecified (&ip0->src_address);

 	  /* Check that source address is unspecified, link-local or else on-link. */
 	  if (!ip6_sadd_unspecified && !ip6_sadd_link_local)
 	    {
 	      u32 src_adj_index0 = ip6_src_lookup_for_packet (im, p0, ip0);

 	      if (ADJ_INDEX_INVALID != src_adj_index0)
 		{
 		  ip_adjacency_t *adj0 = adj_get (src_adj_index0);

 		  /* Allow all realistic-looking rewrite adjacencies to pass */
 		  ni0 = adj0->lookup_next_index;
 		  is_rewrite0 = (ni0 >= IP_LOOKUP_NEXT_ARP) &&
 		    (ni0 < IP6_LOOKUP_N_NEXT);

 		  error0 = ((adj0->rewrite_header.sw_if_index != sw_if_index0
 			     || !is_rewrite0)
 			    ?
 			    ICMP6_ERROR_NEIGHBOR_SOLICITATION_SOURCE_NOT_ON_LINK
 			    : error0);
 		}
 	      else
 		{
 		  error0 =
 		    ICMP6_ERROR_NEIGHBOR_SOLICITATION_SOURCE_NOT_ON_LINK;
 		}
 	    }

 	  o0 = (void *) (h0 + 1);
 	  o0 = ((options_len0 == 8 && o0->header.type == option_type
 		 && o0->header.n_data_u64s == 1) ? o0 : 0);

 	  /* If src address unspecified or link local, donot learn neighbor MAC */
 	  if (PREDICT_TRUE (error0 == ICMP6_ERROR_NONE && o0 != 0 &&
 			    !ip6_sadd_unspecified))
 	    {
 	      ip_neighbor_learn_t learn = {
 		.sw_if_index = sw_if_index0,
 		.type = IP46_TYPE_IP6,
 		.ip.ip6 = (is_solicitation ?
 			   ip0->src_address : h0->target_address),
 	      };
 	      memcpy (&learn.mac, o0->ethernet_address, sizeof (learn.mac));
 	      ip_neighbor_learn_dp (&learn);
 	    }

 	  if (is_solicitation && error0 == ICMP6_ERROR_NONE)
 	    {
 	      /* Check that target address is local to this router. */
 	      fib_node_index_t fei;
 	      u32 fib_index;

 	      fib_index =
 		ip6_fib_table_get_index_for_sw_if_index (sw_if_index0);

 	      if (~0 == fib_index)
 		{
 		  error0 = ICMP6_ERROR_NEIGHBOR_SOLICITATION_SOURCE_UNKNOWN;
 		}
 	      else
 		{
 		  if (ip6_address_is_link_local_unicast (&h0->target_address))
 		    {
 		      fei = ip6_fib_table_lookup_exact_match
 			(ip6_ll_fib_get (sw_if_index0),
 			 &h0->target_address, 128);
 		    }
 		  else
 		    {
 		      fei = ip6_fib_table_lookup_exact_match (fib_index,
 							      &h0->target_address,
 							      128);
 		    }

 		  if (FIB_NODE_INDEX_INVALID == fei)
 		    {
 		      /* The target address is not in the FIB */
 		      error0 =
 			ICMP6_ERROR_NEIGHBOR_SOLICITATION_SOURCE_UNKNOWN;
 		    }
 		  else
 		    {
 		      if (FIB_ENTRY_FLAG_LOCAL &
 			  fib_entry_get_flags_for_source (fei,
 							  FIB_SOURCE_INTERFACE))
 			{
 			  /* It's an address that belongs to one of our interfaces
 			   * that's good. */
 			}
 		      else
 			if (fib_entry_is_sourced
 			    (fei, FIB_SOURCE_IP6_ND_PROXY) ||
 			    fib_entry_is_sourced (fei, FIB_SOURCE_IP6_ND))
 			{
 			  /* The address was added by IPv6 Proxy ND config.
 			   * We should only respond to these if the NS arrived on
 			   * the link that has a matching covering prefix */
 			}
 		      else
 			{
 			  error0 =
 			    ICMP6_ERROR_NEIGHBOR_SOLICITATION_SOURCE_UNKNOWN;
 			}
 		    }
 		}
 	    }

 	  if (is_solicitation)
 	    next0 = (error0 != ICMP6_ERROR_NONE
 		     ? ICMP6_NEIGHBOR_SOLICITATION_NEXT_DROP
 		     : ICMP6_NEIGHBOR_SOLICITATION_NEXT_REPLY);
 	  else
 	    {
 	      next0 = 0;
 	      error0 = error0 == ICMP6_ERROR_NONE ?
 		ICMP6_ERROR_NEIGHBOR_ADVERTISEMENTS_RX : error0;
 	    }

 	  if (is_solicitation && error0 == ICMP6_ERROR_NONE)
 	    {
 	      vnet_sw_interface_t *sw_if0;
 	      ethernet_interface_t *eth_if0;
 	      ethernet_header_t *eth0;

 	      /* dst address is either source address or the all-nodes mcast addr */
 	      if (!ip6_sadd_unspecified)
 		ip0->dst_address = ip0->src_address;
 	      else
 		ip6_set_reserved_multicast_address (&ip0->dst_address,
 						    IP6_MULTICAST_SCOPE_link_local,
 						    IP6_MULTICAST_GROUP_ID_all_hosts);

 	      ip0->src_address = h0->target_address;
 	      ip0->hop_limit = 255;
 	      h0->icmp.type = ICMP6_neighbor_advertisement;

 	      sw_if0 = vnet_get_sup_sw_interface (vnm, sw_if_index0);
 	      ASSERT (sw_if0->type == VNET_SW_INTERFACE_TYPE_HARDWARE);
 	      eth_if0 =
 		ethernet_get_interface (&ethernet_main, sw_if0->hw_if_index);
 	      if (eth_if0 && o0)
 		{
 		  clib_memcpy (o0->ethernet_address, eth_if0->address, 6);
 		  o0->header.type =
 		    ICMP6_NEIGHBOR_DISCOVERY_OPTION_target_link_layer_address;
 		}

 	      h0->advertisement_flags = clib_host_to_net_u32
 		(ICMP6_NEIGHBOR_ADVERTISEMENT_FLAG_SOLICITED
 		 | ICMP6_NEIGHBOR_ADVERTISEMENT_FLAG_OVERRIDE);

 	      h0->icmp.checksum = 0;
 	      h0->icmp.checksum =
 		ip6_tcp_udp_icmp_compute_checksum (vm, p0, ip0,
 						   &bogus_length);
 	      ASSERT (bogus_length == 0);

 	      /* Reuse current MAC header, copy SMAC to DMAC and
 	       * interface MAC to SMAC */
 	      vlib_buffer_advance (p0, -ethernet_buffer_header_size (p0));
 	      eth0 = vlib_buffer_get_current (p0);
 	      clib_memcpy (eth0->dst_address, eth0->src_address, 6);
 	      if (eth_if0)
 		clib_memcpy (eth0->src_address, eth_if0->address, 6);

 	      /* Setup input and output sw_if_index for packet */
 	      ASSERT (vnet_buffer (p0)->sw_if_index[VLIB_RX] == sw_if_index0);
 	      vnet_buffer (p0)->sw_if_index[VLIB_TX] = sw_if_index0;
 	      vnet_buffer (p0)->sw_if_index[VLIB_RX] =
 		vnet_main.local_interface_sw_if_index;

 	      n_advertisements_sent++;
 	    }

 	  p0->error = error_node->errors[error0];

 	  vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
 					   to_next, n_left_to_next,
 					   bi0, next0);
 	}

       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
     }

   /* Account for advertisements sent. */
   vlib_error_count (vm, error_node->node_index,
 		    ICMP6_ERROR_NEIGHBOR_ADVERTISEMENTS_TX,
 		    n_advertisements_sent);

   return frame->n_vectors;
 }

 static const ethernet_interface_t *
 ip6_nd_get_eth_itf (u32 sw_if_index)
 {
   const vnet_sw_interface_t *sw;

   /* lookup radv container  - ethernet interfaces only */
   sw = vnet_get_sup_sw_interface (vnet_get_main (), sw_if_index);
   if (sw->type == VNET_SW_INTERFACE_TYPE_HARDWARE)
     return (ethernet_get_interface (&ethernet_main, sw->hw_if_index));

   return (NULL);
 }

 /**
  * @brief called when IP6 is enabled on a link.
  * create and initialize router advertisement parameters with default
  * values for this intfc
  */
 static void
 ip6_nd_link_enable (u32 sw_if_index)
 {
   const ethernet_interface_t *eth;
   ip6_nd_t *ind;

   eth = ip6_nd_get_eth_itf (sw_if_index);

   if (NULL == eth)
     return;

   ASSERT (INDEX_INVALID == ip6_link_delegate_get (sw_if_index,
 						  ip6_nd_delegate_id));

   pool_get_zero (ip6_nd_pool, ind);

   ind->sw_if_index = sw_if_index;

   ip6_link_delegate_update (sw_if_index, ip6_nd_delegate_id,
 			    ind - ip6_nd_pool);
 }

 static void
 ip6_nd_delegate_disable (index_t indi)
 {
   ip6_nd_t *ind;

   ind = pool_elt_at_index (ip6_nd_pool, indi);

   pool_put (ip6_nd_pool, ind);
 }

 static uword
 icmp6_neighbor_solicitation (vlib_main_t * vm,
 			     vlib_node_runtime_t * node, vlib_frame_t * frame)
 {
   return icmp6_neighbor_solicitation_or_advertisement (vm, node, frame,
 						       /* is_solicitation */
 						       1);
 }

 static uword
 icmp6_neighbor_advertisement (vlib_main_t * vm,
 			      vlib_node_runtime_t * node,
 			      vlib_frame_t * frame)
 {
   return icmp6_neighbor_solicitation_or_advertisement (vm, node, frame,
 						       /* is_solicitation */
 						       0);
 }

 /* *INDENT-OFF* */
 VLIB_REGISTER_NODE (ip6_icmp_neighbor_solicitation_node,static) =
 {
   .function = icmp6_neighbor_solicitation,
   .name = "icmp6-neighbor-solicitation",

   .vector_size = sizeof (u32),

   .format_trace = format_icmp6_input_trace,

   .n_next_nodes = ICMP6_NEIGHBOR_SOLICITATION_N_NEXT,
   .next_nodes = {
     [ICMP6_NEIGHBOR_SOLICITATION_NEXT_DROP] = "ip6-drop",
     [ICMP6_NEIGHBOR_SOLICITATION_NEXT_REPLY] = "interface-output",
   },
 };

 VLIB_REGISTER_NODE (ip6_icmp_neighbor_advertisement_node,static) =
 {
   .function = icmp6_neighbor_advertisement,
   .name = "icmp6-neighbor-advertisement",

   .vector_size = sizeof (u32),

   .format_trace = format_icmp6_input_trace,

   .n_next_nodes = 1,
   .next_nodes = {
     [0] = "ip6-punt",
   },
 };
 /* *INDENT-ON* */

 static u8 *
 format_ip6_nd (u8 * s, va_list * args)
 {
   CLIB_UNUSED (index_t indi) = va_arg (*args, index_t);
   u32 indent = va_arg (*args, u32);

   s = format (s, "%UNeighbor Discovery: enabled\n",
 	      format_white_space, indent);

   s = format (s, "%UICMP redirects are disabled\n",
 	      format_white_space, indent + 2);
   s = format (s, "%UICMP unreachables are not sent\n",
 	      format_white_space, indent + 2);
   s = format (s, "%UND DAD is disabled\n", format_white_space, indent + 2);
   //s = format (s, "%UND reachable time is %d milliseconds\n",);

   return (s);
 }

 /**
  * VFT to act as an implementation of a neighbour protocol
  */
 const static ip_neighbor_vft_t ip6_nd_impl_vft = {
   .inv_proxy6_add = ip6_nd_proxy_add,
   .inv_proxy6_del = ip6_nd_proxy_del,
 };

 /**
  * VFT for registering as a delegate to an IP6 link
  */
 const static ip6_link_delegate_vft_t ip6_nd_delegate_vft = {
   .ildv_disable = ip6_nd_delegate_disable,
   .ildv_enable = ip6_nd_link_enable,
   .ildv_format = format_ip6_nd,
 };

 static clib_error_t *
 ip6_nd_init (vlib_main_t * vm)
 {
   icmp6_register_type (vm, ICMP6_neighbor_solicitation,
 		       ip6_icmp_neighbor_solicitation_node.index);
   icmp6_register_type (vm, ICMP6_neighbor_advertisement,
 		       ip6_icmp_neighbor_advertisement_node.index);

   ip_neighbor_register (IP46_TYPE_IP6, &ip6_nd_impl_vft);

   ip6_nd_delegate_id = ip6_link_delegate_register (&ip6_nd_delegate_vft);

   return 0;
 }

 /* *INDENT-OFF* */
 VLIB_INIT_FUNCTION (ip6_nd_init) =
 {
   .runs_after = VLIB_INITS("icmp6_init"),
 };
 /* *INDENT-ON* */

 /*
  * fd.io coding-style-patch-verification: ON
  *
  * Local Variables:
  * eval: (c-set-style "gnu")
  * End:
  */
	/*
	* ip/ip6_neighbor.c: IP6 neighbor handling
	*
	* 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/ip6-nd/ip6_nd.h>

	#include <vnet/ip-neighbor/ip_neighbor.h>
	#include <vnet/ip-neighbor/ip_neighbor_dp.h>

	#include <vnet/fib/ip6_fib.h>
	#include <vnet/ip/ip6_link.h>
	#include <vnet/ip/ip6_ll_table.h>

	/**
	* @file
	* @brief IPv6 Neighbor Adjacency and Neighbor Discovery.
	*
	* The files contains the API and CLI code for managing IPv6 neighbor
	* adjacency tables and neighbor discovery logic.
	*/

	#define DEF_MAX_RADV_INTERVAL 200
	#define DEF_MIN_RADV_INTERVAL .75 * DEF_MAX_RADV_INTERVAL

	typedef struct ip6_nd_t_
	{
	/* local information */
	u32 sw_if_index;

	/* stats */
	u32 n_solicitations_rcvd;
	u32 n_solicitations_dropped;
	} ip6_nd_t;

	static ip6_link_delegate_id_t ip6_nd_delegate_id;
	static ip6_nd_t *ip6_nd_pool;


	typedef enum
	{
	ICMP6_NEIGHBOR_SOLICITATION_NEXT_DROP,
	ICMP6_NEIGHBOR_SOLICITATION_NEXT_REPLY,
	ICMP6_NEIGHBOR_SOLICITATION_N_NEXT,
	} icmp6_neighbor_solicitation_or_advertisement_next_t;

	static_always_inline uword
	icmp6_neighbor_solicitation_or_advertisement (vlib_main_t * vm,
	vlib_node_runtime_t * node,
	vlib_frame_t * frame,
	uword is_solicitation)
	{
	vnet_main_t *vnm = vnet_get_main ();
	ip6_main_t *im = &ip6_main;
	uword n_packets = frame->n_vectors;
	u32 from, to_next;
	u32 n_left_from, n_left_to_next, next_index, n_advertisements_sent;
	icmp6_neighbor_discovery_option_type_t option_type;
	vlib_node_runtime_t *error_node =
	vlib_node_get_runtime (vm, ip6_icmp_input_node.index);
	int bogus_length;

	from = vlib_frame_vector_args (frame);
	n_left_from = n_packets;
	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 (icmp6_input_trace_t));

	option_type =
	(is_solicitation
	? ICMP6_NEIGHBOR_DISCOVERY_OPTION_source_link_layer_address
	: ICMP6_NEIGHBOR_DISCOVERY_OPTION_target_link_layer_address);
	n_advertisements_sent = 0;

	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)
	{
	vlib_buffer_t *p0;
	ip6_header_t *ip0;
	icmp6_neighbor_solicitation_or_advertisement_header_t *h0;
	icmp6_neighbor_discovery_ethernet_link_layer_address_option_t *o0;
	u32 bi0, options_len0, sw_if_index0, next0, error0;
	u32 ip6_sadd_link_local, ip6_sadd_unspecified;
	int is_rewrite0;
	u32 ni0;

	bi0 = to_next[0] = from[0];

	from += 1;
	to_next += 1;
	n_left_from -= 1;
	n_left_to_next -= 1;

	p0 = vlib_get_buffer (vm, bi0);
	ip0 = vlib_buffer_get_current (p0);
	h0 = ip6_next_header (ip0);
	options_len0 =
	clib_net_to_host_u16 (ip0->payload_length) - sizeof (h0[0]);

	error0 = ICMP6_ERROR_NONE;
	sw_if_index0 = vnet_buffer (p0)->sw_if_index[VLIB_RX];
	ip6_sadd_link_local =
	ip6_address_is_link_local_unicast (&ip0->src_address);
	ip6_sadd_unspecified =
	ip6_address_is_unspecified (&ip0->src_address);

	/* Check that source address is unspecified, link-local or else on-link. */
	if (!ip6_sadd_unspecified && !ip6_sadd_link_local)
	{
	u32 src_adj_index0 = ip6_src_lookup_for_packet (im, p0, ip0);

	if (ADJ_INDEX_INVALID != src_adj_index0)
	{
	ip_adjacency_t *adj0 = adj_get (src_adj_index0);

	/* Allow all realistic-looking rewrite adjacencies to pass */
	ni0 = adj0->lookup_next_index;
	is_rewrite0 = (ni0 >= IP_LOOKUP_NEXT_ARP) &&
	(ni0 < IP6_LOOKUP_N_NEXT);

	error0 = ((adj0->rewrite_header.sw_if_index != sw_if_index0
	\|\| !is_rewrite0)
	?
	ICMP6_ERROR_NEIGHBOR_SOLICITATION_SOURCE_NOT_ON_LINK
	: error0);
	}
	else
	{
	error0 =
	ICMP6_ERROR_NEIGHBOR_SOLICITATION_SOURCE_NOT_ON_LINK;
	}
	}

	o0 = (void *) (h0 + 1);
	o0 = ((options_len0 == 8 && o0->header.type == option_type
	&& o0->header.n_data_u64s == 1) ? o0 : 0);

	/* If src address unspecified or link local, donot learn neighbor MAC */
	if (PREDICT_TRUE (error0 == ICMP6_ERROR_NONE && o0 != 0 &&
	!ip6_sadd_unspecified))
	{
	ip_neighbor_learn_t learn = {
	.sw_if_index = sw_if_index0,
	.type = IP46_TYPE_IP6,
	.ip.ip6 = (is_solicitation ?
	ip0->src_address : h0->target_address),
	};
	memcpy (&learn.mac, o0->ethernet_address, sizeof (learn.mac));
	ip_neighbor_learn_dp (&learn);
	}

	if (is_solicitation && error0 == ICMP6_ERROR_NONE)
	{
	/* Check that target address is local to this router. */
	fib_node_index_t fei;
	u32 fib_index;

	fib_index =
	ip6_fib_table_get_index_for_sw_if_index (sw_if_index0);

	if (~0 == fib_index)
	{
	error0 = ICMP6_ERROR_NEIGHBOR_SOLICITATION_SOURCE_UNKNOWN;
	}
	else
	{
	if (ip6_address_is_link_local_unicast (&h0->target_address))
	{
	fei = ip6_fib_table_lookup_exact_match
	(ip6_ll_fib_get (sw_if_index0),
	&h0->target_address, 128);
	}
	else
	{
	fei = ip6_fib_table_lookup_exact_match (fib_index,
	&h0->target_address,
	128);
	}

	if (FIB_NODE_INDEX_INVALID == fei)
	{
	/* The target address is not in the FIB */
	error0 =
	ICMP6_ERROR_NEIGHBOR_SOLICITATION_SOURCE_UNKNOWN;
	}
	else
	{
	if (FIB_ENTRY_FLAG_LOCAL &
	fib_entry_get_flags_for_source (fei,
	FIB_SOURCE_INTERFACE))
	{
	/* It's an address that belongs to one of our interfaces
	* that's good. */
	}
	else
	if (fib_entry_is_sourced
	(fei, FIB_SOURCE_IP6_ND_PROXY) \|\|
	fib_entry_is_sourced (fei, FIB_SOURCE_IP6_ND))
	{
	/* The address was added by IPv6 Proxy ND config.
	* We should only respond to these if the NS arrived on
	* the link that has a matching covering prefix */
	}
	else
	{
	error0 =
	ICMP6_ERROR_NEIGHBOR_SOLICITATION_SOURCE_UNKNOWN;
	}
	}
	}
	}

	if (is_solicitation)
	next0 = (error0 != ICMP6_ERROR_NONE
	? ICMP6_NEIGHBOR_SOLICITATION_NEXT_DROP
	: ICMP6_NEIGHBOR_SOLICITATION_NEXT_REPLY);
	else
	{
	next0 = 0;
	error0 = error0 == ICMP6_ERROR_NONE ?
	ICMP6_ERROR_NEIGHBOR_ADVERTISEMENTS_RX : error0;
	}

	if (is_solicitation && error0 == ICMP6_ERROR_NONE)
	{
	vnet_sw_interface_t *sw_if0;
	ethernet_interface_t *eth_if0;
	ethernet_header_t *eth0;

	/* dst address is either source address or the all-nodes mcast addr */
	if (!ip6_sadd_unspecified)
	ip0->dst_address = ip0->src_address;
	else
	ip6_set_reserved_multicast_address (&ip0->dst_address,
	IP6_MULTICAST_SCOPE_link_local,
	IP6_MULTICAST_GROUP_ID_all_hosts);

	ip0->src_address = h0->target_address;
	ip0->hop_limit = 255;
	h0->icmp.type = ICMP6_neighbor_advertisement;

	sw_if0 = vnet_get_sup_sw_interface (vnm, sw_if_index0);
	ASSERT (sw_if0->type == VNET_SW_INTERFACE_TYPE_HARDWARE);
	eth_if0 =
	ethernet_get_interface (&ethernet_main, sw_if0->hw_if_index);
	if (eth_if0 && o0)
	{
	clib_memcpy (o0->ethernet_address, eth_if0->address, 6);
	o0->header.type =
	ICMP6_NEIGHBOR_DISCOVERY_OPTION_target_link_layer_address;
	}

	h0->advertisement_flags = clib_host_to_net_u32
	(ICMP6_NEIGHBOR_ADVERTISEMENT_FLAG_SOLICITED
	\| ICMP6_NEIGHBOR_ADVERTISEMENT_FLAG_OVERRIDE);

	h0->icmp.checksum = 0;
	h0->icmp.checksum =
	ip6_tcp_udp_icmp_compute_checksum (vm, p0, ip0,
	&bogus_length);
	ASSERT (bogus_length == 0);

	/* Reuse current MAC header, copy SMAC to DMAC and
	* interface MAC to SMAC */
	vlib_buffer_advance (p0, -ethernet_buffer_header_size (p0));
	eth0 = vlib_buffer_get_current (p0);
	clib_memcpy (eth0->dst_address, eth0->src_address, 6);
	if (eth_if0)
	clib_memcpy (eth0->src_address, eth_if0->address, 6);

	/* Setup input and output sw_if_index for packet */
	ASSERT (vnet_buffer (p0)->sw_if_index[VLIB_RX] == sw_if_index0);
	vnet_buffer (p0)->sw_if_index[VLIB_TX] = sw_if_index0;
	vnet_buffer (p0)->sw_if_index[VLIB_RX] =
	vnet_main.local_interface_sw_if_index;

	n_advertisements_sent++;
	}

	p0->error = error_node->errors[error0];

	vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
	to_next, n_left_to_next,
	bi0, next0);
	}

	vlib_put_next_frame (vm, node, next_index, n_left_to_next);
	}

	/* Account for advertisements sent. */
	vlib_error_count (vm, error_node->node_index,
	ICMP6_ERROR_NEIGHBOR_ADVERTISEMENTS_TX,
	n_advertisements_sent);

	return frame->n_vectors;
	}

	static const ethernet_interface_t *
	ip6_nd_get_eth_itf (u32 sw_if_index)
	{
	const vnet_sw_interface_t *sw;

	/* lookup radv container - ethernet interfaces only */
	sw = vnet_get_sup_sw_interface (vnet_get_main (), sw_if_index);
	if (sw->type == VNET_SW_INTERFACE_TYPE_HARDWARE)
	return (ethernet_get_interface (&ethernet_main, sw->hw_if_index));

	return (NULL);
	}

	/**
	* @brief called when IP6 is enabled on a link.
	* create and initialize router advertisement parameters with default
	* values for this intfc
	*/
	static void
	ip6_nd_link_enable (u32 sw_if_index)
	{
	const ethernet_interface_t *eth;
	ip6_nd_t *ind;

	eth = ip6_nd_get_eth_itf (sw_if_index);

	if (NULL == eth)
	return;

	ASSERT (INDEX_INVALID == ip6_link_delegate_get (sw_if_index,
	ip6_nd_delegate_id));

	pool_get_zero (ip6_nd_pool, ind);

	ind->sw_if_index = sw_if_index;

	ip6_link_delegate_update (sw_if_index, ip6_nd_delegate_id,
	ind - ip6_nd_pool);
	}

	static void
	ip6_nd_delegate_disable (index_t indi)
	{
	ip6_nd_t *ind;

	ind = pool_elt_at_index (ip6_nd_pool, indi);

	pool_put (ip6_nd_pool, ind);
	}

	static uword
	icmp6_neighbor_solicitation (vlib_main_t * vm,
	vlib_node_runtime_t * node, vlib_frame_t * frame)
	{
	return icmp6_neighbor_solicitation_or_advertisement (vm, node, frame,
	/* is_solicitation */
	1);
	}

	static uword
	icmp6_neighbor_advertisement (vlib_main_t * vm,
	vlib_node_runtime_t * node,
	vlib_frame_t * frame)
	{
	return icmp6_neighbor_solicitation_or_advertisement (vm, node, frame,
	/* is_solicitation */
	0);
	}

	/* INDENT-OFF */
	VLIB_REGISTER_NODE (ip6_icmp_neighbor_solicitation_node,static) =
	{
	.function = icmp6_neighbor_solicitation,
	.name = "icmp6-neighbor-solicitation",

	.vector_size = sizeof (u32),

	.format_trace = format_icmp6_input_trace,

	.n_next_nodes = ICMP6_NEIGHBOR_SOLICITATION_N_NEXT,
	.next_nodes = {
	[ICMP6_NEIGHBOR_SOLICITATION_NEXT_DROP] = "ip6-drop",
	[ICMP6_NEIGHBOR_SOLICITATION_NEXT_REPLY] = "interface-output",
	},
	};

	VLIB_REGISTER_NODE (ip6_icmp_neighbor_advertisement_node,static) =
	{
	.function = icmp6_neighbor_advertisement,
	.name = "icmp6-neighbor-advertisement",

	.vector_size = sizeof (u32),

	.format_trace = format_icmp6_input_trace,

	.n_next_nodes = 1,
	.next_nodes = {
	[0] = "ip6-punt",
	},
	};
	/* INDENT-ON */

	static u8 *
	format_ip6_nd (u8 * s, va_list * args)
	{
	CLIB_UNUSED (index_t indi) = va_arg (*args, index_t);
	u32 indent = va_arg (*args, u32);

	s = format (s, "%UNeighbor Discovery: enabled\n",
	format_white_space, indent);

	s = format (s, "%UICMP redirects are disabled\n",
	format_white_space, indent + 2);
	s = format (s, "%UICMP unreachables are not sent\n",
	format_white_space, indent + 2);
	s = format (s, "%UND DAD is disabled\n", format_white_space, indent + 2);
	//s = format (s, "%UND reachable time is %d milliseconds\n",);

	return (s);
	}

	/**
	* VFT to act as an implementation of a neighbour protocol
	*/
	const static ip_neighbor_vft_t ip6_nd_impl_vft = {
	.inv_proxy6_add = ip6_nd_proxy_add,
	.inv_proxy6_del = ip6_nd_proxy_del,
	};

	/**
	* VFT for registering as a delegate to an IP6 link
	*/
	const static ip6_link_delegate_vft_t ip6_nd_delegate_vft = {
	.ildv_disable = ip6_nd_delegate_disable,
	.ildv_enable = ip6_nd_link_enable,
	.ildv_format = format_ip6_nd,
	};

	static clib_error_t *
	ip6_nd_init (vlib_main_t * vm)
	{
	icmp6_register_type (vm, ICMP6_neighbor_solicitation,
	ip6_icmp_neighbor_solicitation_node.index);
	icmp6_register_type (vm, ICMP6_neighbor_advertisement,
	ip6_icmp_neighbor_advertisement_node.index);

	ip_neighbor_register (IP46_TYPE_IP6, &ip6_nd_impl_vft);

	ip6_nd_delegate_id = ip6_link_delegate_register (&ip6_nd_delegate_vft);

	return 0;
	}

	/* INDENT-OFF */
	VLIB_INIT_FUNCTION (ip6_nd_init) =
	{
	.runs_after = VLIB_INITS("icmp6_init"),
	};
	/* INDENT-ON */

	/*
	* fd.io coding-style-patch-verification: ON
	*
	* Local Variables:
	* eval: (c-set-style "gnu")
	* End:
	*/