src/vnet/ipip/ipip.c - fdio/vpp - Gitiles

 /*
  * ipip.c: ipip
  *
  * Copyright (c) 2018 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 aipiped 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 <stddef.h>
 #include <vnet/adj/adj_midchain.h>
 #include <vnet/ipip/ipip.h>
 #include <vnet/vnet.h>
 #include <vnet/adj/adj_nbr.h>
 #include <vnet/adj/adj_midchain.h>
 #include <vnet/fib/ip4_fib.h>
 #include <vnet/fib/ip6_fib.h>
 #include <vnet/ip/format.h>
 #include <vnet/ipip/ipip.h>

 ipip_main_t ipip_main;

 /* Packet trace structure */
 typedef struct
 {
   u32 tunnel_id;
   u32 length;
   ip46_address_t src;
   ip46_address_t dst;
 } ipip_tx_trace_t;

 u8 *
 format_ipip_tx_trace (u8 * s, va_list * args)
 {
   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
   ipip_tx_trace_t *t = va_arg (*args, ipip_tx_trace_t *);

   s =
     format (s, "IPIP: tunnel %d len %d src %U dst %U", t->tunnel_id,
 	    t->length, format_ip46_address, &t->src, IP46_TYPE_ANY,
 	    format_ip46_address, &t->dst, IP46_TYPE_ANY);
   return s;
 }

 static u8 *
 ipip_build_rewrite (vnet_main_t * vnm, u32 sw_if_index,
 		    vnet_link_t link_type, const void *dst_address)
 {
   ip4_header_t *ip4;
   ip6_header_t *ip6;
   u8 *rewrite = NULL;
   ipip_tunnel_t *t = ipip_tunnel_db_find_by_sw_if_index (sw_if_index);

   if (!t)
     /* not one of ours */
     return (0);

   switch (t->transport)
     {
     case IPIP_TRANSPORT_IP4:
       vec_validate (rewrite, sizeof (*ip4) - 1);
       ip4 = (ip4_header_t *) rewrite;
       ip4->ip_version_and_header_length = 0x45;
       ip4->ttl = 64;
       /* fixup ip4 header length, protocol and checksum after-the-fact */
       ip4->src_address.as_u32 = t->tunnel_src.ip4.as_u32;
       ip4->dst_address.as_u32 = t->tunnel_dst.ip4.as_u32;
       ip4->checksum = ip4_header_checksum (ip4);
       if (!(t->flags & IPIP_TUNNEL_FLAG_ENCAP_COPY_DSCP))
 	ip4_header_set_dscp (ip4, t->dscp);
       if (t->flags & IPIP_TUNNEL_FLAG_ENCAP_SET_DF)
 	ip4_header_set_df (ip4);
       break;

     case IPIP_TRANSPORT_IP6:
       vec_validate (rewrite, sizeof (*ip6) - 1);
       ip6 = (ip6_header_t *) rewrite;
       ip6->ip_version_traffic_class_and_flow_label =
 	clib_host_to_net_u32 (6 << 28);
       ip6->hop_limit = 64;
       /* fixup ip6 header length and protocol after-the-fact */
       ip6->src_address.as_u64[0] = t->tunnel_src.ip6.as_u64[0];
       ip6->src_address.as_u64[1] = t->tunnel_src.ip6.as_u64[1];
       ip6->dst_address.as_u64[0] = t->tunnel_dst.ip6.as_u64[0];
       ip6->dst_address.as_u64[1] = t->tunnel_dst.ip6.as_u64[1];
       if (!(t->flags & IPIP_TUNNEL_FLAG_ENCAP_COPY_DSCP))
 	ip6_set_dscp_network_order (ip6, t->dscp);
       break;

     default:
       /* pass through */
       ;
     }
   return (rewrite);
 }

 static void
 ipip4_fixup (vlib_main_t * vm, const ip_adjacency_t * adj, vlib_buffer_t * b,
 	     const void *data)
 {
   ip4_header_t *ip4;
   const ipip_tunnel_t *t = data;

   ip4 = vlib_buffer_get_current (b);
   ip4->length = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b));
   switch (adj->ia_link)
     {
     case VNET_LINK_IP6:
       ip4->protocol = IP_PROTOCOL_IPV6;
       if (t->flags & IPIP_TUNNEL_FLAG_ENCAP_COPY_DSCP)
 	ip4_header_set_dscp (ip4,
 			     ip6_dscp_network_order ((ip6_header_t *) (ip4 +
 								       1)));
       if (t->flags & IPIP_TUNNEL_FLAG_ENCAP_COPY_ECN)
 	ip4_header_set_ecn (ip4,
 			    ip6_ecn_network_order ((ip6_header_t *) (ip4 +
 								     1)));
       break;

     case VNET_LINK_IP4:
       ip4->protocol = IP_PROTOCOL_IP_IN_IP;
       if (t->flags & IPIP_TUNNEL_FLAG_ENCAP_COPY_DSCP)
 	ip4_header_set_dscp (ip4, ip4_header_get_dscp (ip4 + 1));
       if (t->flags & IPIP_TUNNEL_FLAG_ENCAP_COPY_ECN)
 	ip4_header_set_ecn (ip4, ip4_header_get_ecn (ip4 + 1));
       if ((t->flags & IPIP_TUNNEL_FLAG_ENCAP_COPY_DF) &&
 	  ip4_header_get_df (ip4 + 1))
 	ip4_header_set_df (ip4);
       break;

     default:
       break;
     }

   ip4->checksum = ip4_header_checksum (ip4);
 }

 static void
 ipip6_fixup (vlib_main_t * vm, const ip_adjacency_t * adj, vlib_buffer_t * b,
 	     const void *data)
 {
   ip6_header_t *ip6;
   const ipip_tunnel_t *t = data;

   /* Must set locally originated otherwise we're not allowed to
      fragment the packet later */
   b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;

   ip6 = vlib_buffer_get_current (b);
   ip6->payload_length =
     clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b) -
 			  sizeof (*ip6));
   switch (adj->ia_link)
     {
     case VNET_LINK_IP6:
       ip6->protocol = IP_PROTOCOL_IPV6;
       if (t->flags & IPIP_TUNNEL_FLAG_ENCAP_COPY_DSCP)
 	ip6_set_dscp_network_order (ip6, ip6_dscp_network_order (ip6 + 1));
       if (t->flags & IPIP_TUNNEL_FLAG_ENCAP_COPY_ECN)
 	ip6_set_ecn_network_order (ip6, ip6_ecn_network_order (ip6 + 1));
       break;

     case VNET_LINK_IP4:
       ip6->protocol = IP_PROTOCOL_IP_IN_IP;
       if (t->flags & IPIP_TUNNEL_FLAG_ENCAP_COPY_DSCP)
 	ip6_set_dscp_network_order
 	  (ip6, ip4_header_get_dscp ((ip4_header_t *) (ip6 + 1)));
       if (t->flags & IPIP_TUNNEL_FLAG_ENCAP_COPY_ECN)
 	ip6_set_ecn_network_order
 	  (ip6, ip4_header_get_ecn ((ip4_header_t *) (ip6 + 1)));
       break;

     default:
       break;
     }
 }

 static void
 ipip_tunnel_stack (adj_index_t ai)
 {
   ip_adjacency_t *adj;
   ipip_tunnel_t *t;
   u32 sw_if_index;

   adj = adj_get (ai);
   sw_if_index = adj->rewrite_header.sw_if_index;

   t = ipip_tunnel_db_find_by_sw_if_index (sw_if_index);
   if (!t)
     return;

   if ((vnet_hw_interface_get_flags (vnet_get_main (), t->hw_if_index) &
        VNET_HW_INTERFACE_FLAG_LINK_UP) == 0)
     {
       adj_midchain_delegate_unstack (ai);
     }
   else
     {
       /* *INDENT-OFF* */
       fib_prefix_t dst = {
         .fp_len = t->transport == IPIP_TRANSPORT_IP6 ? 128 : 32,
         .fp_proto = (t->transport == IPIP_TRANSPORT_IP6 ?
                      FIB_PROTOCOL_IP6 :
                      FIB_PROTOCOL_IP4),
         .fp_addr = t->tunnel_dst
       };
       /* *INDENT-ON* */

       adj_midchain_delegate_stack (ai, t->fib_index, &dst);
     }
 }

 static adj_walk_rc_t
 ipip_adj_walk_cb (adj_index_t ai, void *ctx)
 {
   ipip_tunnel_stack (ai);

   return (ADJ_WALK_RC_CONTINUE);
 }

 static void
 ipip_tunnel_restack (ipip_tunnel_t * gt)
 {
   fib_protocol_t proto;

   /*
    * walk all the adjacencies on th IPIP interface and restack them
    */
   FOR_EACH_FIB_IP_PROTOCOL (proto)
   {
     adj_nbr_walk (gt->sw_if_index, proto, ipip_adj_walk_cb, NULL);
   }
 }

 void
 ipip_update_adj (vnet_main_t * vnm, u32 sw_if_index, adj_index_t ai)
 {
   adj_midchain_fixup_t f;
   ipip_tunnel_t *t;
   adj_flags_t af;

   t = ipip_tunnel_db_find_by_sw_if_index (sw_if_index);
   if (!t)
     return;

   f = t->transport == IPIP_TRANSPORT_IP6 ? ipip6_fixup : ipip4_fixup;
   af = ADJ_FLAG_MIDCHAIN_IP_STACK;
   if (VNET_LINK_ETHERNET == adj_get_link_type (ai))
     af |= ADJ_FLAG_MIDCHAIN_NO_COUNT;

   adj_nbr_midchain_update_rewrite (ai, f, t, af,
 				   ipip_build_rewrite (vnm,
 						       sw_if_index,
 						       adj_get_link_type
 						       (ai), NULL));
   ipip_tunnel_stack (ai);
 }

 u8 *
 format_ipip_tunnel_flags (u8 * s, va_list * args)
 {
   ipip_tunnel_flags_t f = va_arg (*args, int);

   if (f == IPIP_TUNNEL_FLAG_NONE)
     return (format (s, "none"));

 #define _(a,b,c) if (f & IPIP_TUNNEL_FLAG_##a) s = format(s, "%s ", b);
   forech_ipip_tunnel_flag
 #undef _
     return (s);
 }

 static u8 *
 format_ipip_tunnel_name (u8 * s, va_list * args)
 {
   u32 dev_instance = va_arg (*args, u32);
   ipip_main_t *gm = &ipip_main;
   ipip_tunnel_t *t;

   if (dev_instance >= vec_len (gm->tunnels))
     return format (s, "<improperly-referenced>");

   t = pool_elt_at_index (gm->tunnels, dev_instance);
   return format (s, "ipip%d", t->user_instance);
 }

 static u8 *
 format_ipip_device (u8 * s, va_list * args)
 {
   u32 dev_instance = va_arg (*args, u32);
   CLIB_UNUSED (int verbose) = va_arg (*args, int);

   s = format (s, "IPIP tunnel: id %d\n", dev_instance);
   return s;
 }

 static clib_error_t *
 ipip_interface_admin_up_down (vnet_main_t * vnm, u32 hw_if_index, u32 flags)
 {
   vnet_hw_interface_t *hi;
   ipip_tunnel_t *t;

   hi = vnet_get_hw_interface (vnm, hw_if_index);

   t = ipip_tunnel_db_find_by_sw_if_index (hi->sw_if_index);
   if (!t)
     return 0;

   if (flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP)
     vnet_hw_interface_set_flags (vnm, hw_if_index,
 				 VNET_HW_INTERFACE_FLAG_LINK_UP);
   else
     vnet_hw_interface_set_flags (vnm, hw_if_index, 0 /* down */ );

   ipip_tunnel_restack (t);

   return /* no error */ 0;
 }

 static int
 ipip_tunnel_desc (u32 sw_if_index,
 		  ip46_address_t * src, ip46_address_t * dst, u8 * is_l2)
 {
   ipip_tunnel_t *t;

   t = ipip_tunnel_db_find_by_sw_if_index (sw_if_index);
   if (!t)
     return -1;

   *src = t->tunnel_src;
   *dst = t->tunnel_dst;
   *is_l2 = 0;

   return (0);
 }

 /* *INDENT-OFF* */
 VNET_DEVICE_CLASS(ipip_device_class) = {
     .name = "IPIP tunnel device",
     .format_device_name = format_ipip_tunnel_name,
     .format_device = format_ipip_device,
     .format_tx_trace = format_ipip_tx_trace,
     .admin_up_down_function = ipip_interface_admin_up_down,
     .ip_tun_desc = ipip_tunnel_desc,
 #ifdef SOON
     .clear counter = 0;
 #endif
 };

 VNET_HW_INTERFACE_CLASS(ipip_hw_interface_class) = {
     .name = "IPIP",
     //.format_header = format_ipip_header_with_length,
     //.unformat_header = unformat_ipip_header,
     .build_rewrite = ipip_build_rewrite,
     .update_adjacency = ipip_update_adj,
     .flags = VNET_HW_INTERFACE_CLASS_FLAG_P2P,
 };
 /* *INDENT-ON* */

 ipip_tunnel_t *
 ipip_tunnel_db_find (ipip_tunnel_key_t * key)
 {
   ipip_main_t *gm = &ipip_main;
   uword *p;

   p = hash_get_mem (gm->tunnel_by_key, key);
   if (!p)
     return (NULL);
   return (pool_elt_at_index (gm->tunnels, p[0]));
 }

 ipip_tunnel_t *
 ipip_tunnel_db_find_by_sw_if_index (u32 sw_if_index)
 {
   ipip_main_t *gm = &ipip_main;
   if (vec_len (gm->tunnel_index_by_sw_if_index) <= sw_if_index)
     return NULL;
   u32 ti = gm->tunnel_index_by_sw_if_index[sw_if_index];
   if (ti == ~0)
     return NULL;
   return pool_elt_at_index (gm->tunnels, ti);
 }

 void
 ipip_tunnel_db_add (ipip_tunnel_t * t, ipip_tunnel_key_t * key)
 {
   ipip_main_t *gm = &ipip_main;

   t->key = clib_mem_alloc (sizeof (*t->key));
   clib_memcpy (t->key, key, sizeof (*key));
   hash_set_mem (gm->tunnel_by_key, t->key, t->dev_instance);
 }

 void
 ipip_tunnel_db_remove (ipip_tunnel_t * t)
 {
   ipip_main_t *gm = &ipip_main;

   hash_unset_mem (gm->tunnel_by_key, t->key);
   clib_mem_free (t->key);
   t->key = NULL;
 }

 int
 ipip_add_tunnel (ipip_transport_t transport,
 		 u32 instance, ip46_address_t * src, ip46_address_t * dst,
 		 u32 fib_index, ipip_tunnel_flags_t flags,
 		 ip_dscp_t dscp, u32 * sw_if_indexp)
 {
   ipip_main_t *gm = &ipip_main;
   vnet_main_t *vnm = gm->vnet_main;
   ip4_main_t *im4 = &ip4_main;
   ip6_main_t *im6 = &ip6_main;
   ipip_tunnel_t *t;
   vnet_hw_interface_t *hi;
   u32 hw_if_index, sw_if_index;
   ipip_tunnel_key_t key = {.transport = transport,
     .fib_index = fib_index,
     .src = *src,
     .dst = *dst
   };
   t = ipip_tunnel_db_find (&key);
   if (t)
     {
       if (sw_if_indexp)
 	sw_if_indexp[0] = t->sw_if_index;
       return VNET_API_ERROR_IF_ALREADY_EXISTS;
     }

   pool_get_aligned (gm->tunnels, t, CLIB_CACHE_LINE_BYTES);
   clib_memset (t, 0, sizeof (*t));

   /* Reconcile the real dev_instance and a possible requested instance */
   u32 t_idx = t - gm->tunnels;	/* tunnel index (or instance) */
   u32 u_idx = instance;		/* user specified instance */
   if (u_idx == ~0)
     u_idx = t_idx;
   if (hash_get (gm->instance_used, u_idx))
     {
       pool_put (gm->tunnels, t);
       return VNET_API_ERROR_INSTANCE_IN_USE;
     }
   hash_set (gm->instance_used, u_idx, 1);

   t->dev_instance = t_idx;	/* actual */
   t->user_instance = u_idx;	/* name */

   hw_if_index = vnet_register_interface (vnm, ipip_device_class.index, t_idx,
 					 ipip_hw_interface_class.index,
 					 t_idx);

   hi = vnet_get_hw_interface (vnm, hw_if_index);
   sw_if_index = hi->sw_if_index;

   t->hw_if_index = hw_if_index;
   t->fib_index = fib_index;
   t->sw_if_index = sw_if_index;
   t->dscp = dscp;
   t->flags = flags;
   t->transport = transport;

   vec_validate_init_empty (gm->tunnel_index_by_sw_if_index, sw_if_index, ~0);
   gm->tunnel_index_by_sw_if_index[sw_if_index] = t_idx;

   if (t->transport == IPIP_TRANSPORT_IP4)
     {
       vec_validate (im4->fib_index_by_sw_if_index, sw_if_index);
       hi->min_packet_bytes = 64 + sizeof (ip4_header_t);
     }
   else
     {
       vec_validate (im6->fib_index_by_sw_if_index, sw_if_index);
       hi->min_packet_bytes = 64 + sizeof (ip6_header_t);
     }

   /* Standard default ipip MTU. */
   vnet_sw_interface_set_mtu (vnm, sw_if_index, 9000);

   t->tunnel_src = *src;
   t->tunnel_dst = *dst;

   ipip_tunnel_db_add (t, &key);

   if (sw_if_indexp)
     *sw_if_indexp = sw_if_index;

   if (t->transport == IPIP_TRANSPORT_IP6 && !gm->ip6_protocol_registered)
     {
       ip6_register_protocol (IP_PROTOCOL_IP_IN_IP, ipip6_input_node.index);
       ip6_register_protocol (IP_PROTOCOL_IPV6, ipip6_input_node.index);
       gm->ip6_protocol_registered = true;
     }
   else if (t->transport == IPIP_TRANSPORT_IP4 && !gm->ip4_protocol_registered)
     {
       ip4_register_protocol (IP_PROTOCOL_IP_IN_IP, ipip4_input_node.index);
       ip4_register_protocol (IP_PROTOCOL_IPV6, ipip4_input_node.index);
       gm->ip4_protocol_registered = true;
     }
   return 0;
 }

 int
 ipip_del_tunnel (u32 sw_if_index)
 {
   ipip_main_t *gm = &ipip_main;
   vnet_main_t *vnm = gm->vnet_main;
   ipip_tunnel_t *t;


   t = ipip_tunnel_db_find_by_sw_if_index (sw_if_index);
   if (t == NULL)
     return VNET_API_ERROR_NO_SUCH_ENTRY;

   vnet_sw_interface_set_flags (vnm, sw_if_index, 0 /* down */ );
   gm->tunnel_index_by_sw_if_index[sw_if_index] = ~0;
   vnet_delete_hw_interface (vnm, t->hw_if_index);
   hash_unset (gm->instance_used, t->user_instance);
   ipip_tunnel_db_remove (t);
   pool_put (gm->tunnels, t);

   return 0;
 }

 static clib_error_t *
 ipip_init (vlib_main_t * vm)
 {
   ipip_main_t *gm = &ipip_main;

   clib_memset (gm, 0, sizeof (gm[0]));
   gm->vlib_main = vm;
   gm->vnet_main = vnet_get_main ();
   gm->tunnel_by_key =
     hash_create_mem (0, sizeof (ipip_tunnel_key_t), sizeof (uword));

   return 0;
 }

 VLIB_INIT_FUNCTION (ipip_init);

 /*
  * fd.io coding-style-patch-verification: ON
  *
  * Local Variables:
  * eval: (c-set-style "gnu")
  * End:
  */
	/*
	* ipip.c: ipip
	*
	* Copyright (c) 2018 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 aipiped 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 <stddef.h>
	#include <vnet/adj/adj_midchain.h>
	#include <vnet/ipip/ipip.h>
	#include <vnet/vnet.h>
	#include <vnet/adj/adj_nbr.h>
	#include <vnet/adj/adj_midchain.h>
	#include <vnet/fib/ip4_fib.h>
	#include <vnet/fib/ip6_fib.h>
	#include <vnet/ip/format.h>
	#include <vnet/ipip/ipip.h>

	ipip_main_t ipip_main;

	/* Packet trace structure */
	typedef struct
	{
	u32 tunnel_id;
	u32 length;
	ip46_address_t src;
	ip46_address_t dst;
	} ipip_tx_trace_t;

	u8 *
	format_ipip_tx_trace (u8 * s, va_list * args)
	{
	CLIB_UNUSED (vlib_main_t * vm) = va_arg (args, vlib_main_t );
	CLIB_UNUSED (vlib_node_t * node) = va_arg (args, vlib_node_t );
	ipip_tx_trace_t t = va_arg (args, ipip_tx_trace_t *);

	s =
	format (s, "IPIP: tunnel %d len %d src %U dst %U", t->tunnel_id,
	t->length, format_ip46_address, &t->src, IP46_TYPE_ANY,
	format_ip46_address, &t->dst, IP46_TYPE_ANY);
	return s;
	}

	static u8 *
	ipip_build_rewrite (vnet_main_t * vnm, u32 sw_if_index,
	vnet_link_t link_type, const void *dst_address)
	{
	ip4_header_t *ip4;
	ip6_header_t *ip6;
	u8 *rewrite = NULL;
	ipip_tunnel_t *t = ipip_tunnel_db_find_by_sw_if_index (sw_if_index);

	if (!t)
	/* not one of ours */
	return (0);

	switch (t->transport)
	{
	case IPIP_TRANSPORT_IP4:
	vec_validate (rewrite, sizeof (*ip4) - 1);
	ip4 = (ip4_header_t *) rewrite;
	ip4->ip_version_and_header_length = 0x45;
	ip4->ttl = 64;
	/* fixup ip4 header length, protocol and checksum after-the-fact */
	ip4->src_address.as_u32 = t->tunnel_src.ip4.as_u32;
	ip4->dst_address.as_u32 = t->tunnel_dst.ip4.as_u32;
	ip4->checksum = ip4_header_checksum (ip4);
	if (!(t->flags & IPIP_TUNNEL_FLAG_ENCAP_COPY_DSCP))
	ip4_header_set_dscp (ip4, t->dscp);
	if (t->flags & IPIP_TUNNEL_FLAG_ENCAP_SET_DF)
	ip4_header_set_df (ip4);
	break;

	case IPIP_TRANSPORT_IP6:
	vec_validate (rewrite, sizeof (*ip6) - 1);
	ip6 = (ip6_header_t *) rewrite;
	ip6->ip_version_traffic_class_and_flow_label =
	clib_host_to_net_u32 (6 << 28);
	ip6->hop_limit = 64;
	/* fixup ip6 header length and protocol after-the-fact */
	ip6->src_address.as_u64[0] = t->tunnel_src.ip6.as_u64[0];
	ip6->src_address.as_u64[1] = t->tunnel_src.ip6.as_u64[1];
	ip6->dst_address.as_u64[0] = t->tunnel_dst.ip6.as_u64[0];
	ip6->dst_address.as_u64[1] = t->tunnel_dst.ip6.as_u64[1];
	if (!(t->flags & IPIP_TUNNEL_FLAG_ENCAP_COPY_DSCP))
	ip6_set_dscp_network_order (ip6, t->dscp);
	break;

	default:
	/* pass through */
	;
	}
	return (rewrite);
	}

	static void
	ipip4_fixup (vlib_main_t * vm, const ip_adjacency_t * adj, vlib_buffer_t * b,
	const void *data)
	{
	ip4_header_t *ip4;
	const ipip_tunnel_t *t = data;

	ip4 = vlib_buffer_get_current (b);
	ip4->length = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b));
	switch (adj->ia_link)
	{
	case VNET_LINK_IP6:
	ip4->protocol = IP_PROTOCOL_IPV6;
	if (t->flags & IPIP_TUNNEL_FLAG_ENCAP_COPY_DSCP)
	ip4_header_set_dscp (ip4,
	ip6_dscp_network_order ((ip6_header_t *) (ip4 +
	1)));
	if (t->flags & IPIP_TUNNEL_FLAG_ENCAP_COPY_ECN)
	ip4_header_set_ecn (ip4,
	ip6_ecn_network_order ((ip6_header_t *) (ip4 +
	1)));
	break;

	case VNET_LINK_IP4:
	ip4->protocol = IP_PROTOCOL_IP_IN_IP;
	if (t->flags & IPIP_TUNNEL_FLAG_ENCAP_COPY_DSCP)
	ip4_header_set_dscp (ip4, ip4_header_get_dscp (ip4 + 1));
	if (t->flags & IPIP_TUNNEL_FLAG_ENCAP_COPY_ECN)
	ip4_header_set_ecn (ip4, ip4_header_get_ecn (ip4 + 1));
	if ((t->flags & IPIP_TUNNEL_FLAG_ENCAP_COPY_DF) &&
	ip4_header_get_df (ip4 + 1))
	ip4_header_set_df (ip4);
	break;

	default:
	break;
	}

	ip4->checksum = ip4_header_checksum (ip4);
	}

	static void
	ipip6_fixup (vlib_main_t * vm, const ip_adjacency_t * adj, vlib_buffer_t * b,
	const void *data)
	{
	ip6_header_t *ip6;
	const ipip_tunnel_t *t = data;

	/* Must set locally originated otherwise we're not allowed to
	fragment the packet later */
	b->flags \|= VNET_BUFFER_F_LOCALLY_ORIGINATED;

	ip6 = vlib_buffer_get_current (b);
	ip6->payload_length =
	clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b) -
	sizeof (*ip6));
	switch (adj->ia_link)
	{
	case VNET_LINK_IP6:
	ip6->protocol = IP_PROTOCOL_IPV6;
	if (t->flags & IPIP_TUNNEL_FLAG_ENCAP_COPY_DSCP)
	ip6_set_dscp_network_order (ip6, ip6_dscp_network_order (ip6 + 1));
	if (t->flags & IPIP_TUNNEL_FLAG_ENCAP_COPY_ECN)
	ip6_set_ecn_network_order (ip6, ip6_ecn_network_order (ip6 + 1));
	break;

	case VNET_LINK_IP4:
	ip6->protocol = IP_PROTOCOL_IP_IN_IP;
	if (t->flags & IPIP_TUNNEL_FLAG_ENCAP_COPY_DSCP)
	ip6_set_dscp_network_order
	(ip6, ip4_header_get_dscp ((ip4_header_t *) (ip6 + 1)));
	if (t->flags & IPIP_TUNNEL_FLAG_ENCAP_COPY_ECN)
	ip6_set_ecn_network_order
	(ip6, ip4_header_get_ecn ((ip4_header_t *) (ip6 + 1)));
	break;

	default:
	break;
	}
	}

	static void
	ipip_tunnel_stack (adj_index_t ai)
	{
	ip_adjacency_t *adj;
	ipip_tunnel_t *t;
	u32 sw_if_index;

	adj = adj_get (ai);
	sw_if_index = adj->rewrite_header.sw_if_index;

	t = ipip_tunnel_db_find_by_sw_if_index (sw_if_index);
	if (!t)
	return;

	if ((vnet_hw_interface_get_flags (vnet_get_main (), t->hw_if_index) &
	VNET_HW_INTERFACE_FLAG_LINK_UP) == 0)
	{
	adj_midchain_delegate_unstack (ai);
	}
	else
	{
	/* INDENT-OFF */
	fib_prefix_t dst = {
	.fp_len = t->transport == IPIP_TRANSPORT_IP6 ? 128 : 32,
	.fp_proto = (t->transport == IPIP_TRANSPORT_IP6 ?
	FIB_PROTOCOL_IP6 :
	FIB_PROTOCOL_IP4),
	.fp_addr = t->tunnel_dst
	};
	/* INDENT-ON */

	adj_midchain_delegate_stack (ai, t->fib_index, &dst);
	}
	}

	static adj_walk_rc_t
	ipip_adj_walk_cb (adj_index_t ai, void *ctx)
	{
	ipip_tunnel_stack (ai);

	return (ADJ_WALK_RC_CONTINUE);
	}

	static void
	ipip_tunnel_restack (ipip_tunnel_t * gt)
	{
	fib_protocol_t proto;

	/*
	* walk all the adjacencies on th IPIP interface and restack them
	*/
	FOR_EACH_FIB_IP_PROTOCOL (proto)
	{
	adj_nbr_walk (gt->sw_if_index, proto, ipip_adj_walk_cb, NULL);
	}
	}

	void
	ipip_update_adj (vnet_main_t * vnm, u32 sw_if_index, adj_index_t ai)
	{
	adj_midchain_fixup_t f;
	ipip_tunnel_t *t;
	adj_flags_t af;

	t = ipip_tunnel_db_find_by_sw_if_index (sw_if_index);
	if (!t)
	return;

	f = t->transport == IPIP_TRANSPORT_IP6 ? ipip6_fixup : ipip4_fixup;
	af = ADJ_FLAG_MIDCHAIN_IP_STACK;
	if (VNET_LINK_ETHERNET == adj_get_link_type (ai))
	af \|= ADJ_FLAG_MIDCHAIN_NO_COUNT;

	adj_nbr_midchain_update_rewrite (ai, f, t, af,
	ipip_build_rewrite (vnm,
	sw_if_index,
	adj_get_link_type
	(ai), NULL));
	ipip_tunnel_stack (ai);
	}

	u8 *
	format_ipip_tunnel_flags (u8 * s, va_list * args)
	{
	ipip_tunnel_flags_t f = va_arg (*args, int);

	if (f == IPIP_TUNNEL_FLAG_NONE)
	return (format (s, "none"));

	#define _(a,b,c) if (f & IPIP_TUNNEL_FLAG_##a) s = format(s, "%s ", b);
	forech_ipip_tunnel_flag
	#undef _
	return (s);
	}

	static u8 *
	format_ipip_tunnel_name (u8 * s, va_list * args)
	{
	u32 dev_instance = va_arg (*args, u32);
	ipip_main_t *gm = &ipip_main;
	ipip_tunnel_t *t;

	if (dev_instance >= vec_len (gm->tunnels))
	return format (s, "<improperly-referenced>");

	t = pool_elt_at_index (gm->tunnels, dev_instance);
	return format (s, "ipip%d", t->user_instance);
	}

	static u8 *
	format_ipip_device (u8 * s, va_list * args)
	{
	u32 dev_instance = va_arg (*args, u32);
	CLIB_UNUSED (int verbose) = va_arg (*args, int);

	s = format (s, "IPIP tunnel: id %d\n", dev_instance);
	return s;
	}

	static clib_error_t *
	ipip_interface_admin_up_down (vnet_main_t * vnm, u32 hw_if_index, u32 flags)
	{
	vnet_hw_interface_t *hi;
	ipip_tunnel_t *t;

	hi = vnet_get_hw_interface (vnm, hw_if_index);

	t = ipip_tunnel_db_find_by_sw_if_index (hi->sw_if_index);
	if (!t)
	return 0;

	if (flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP)
	vnet_hw_interface_set_flags (vnm, hw_if_index,
	VNET_HW_INTERFACE_FLAG_LINK_UP);
	else
	vnet_hw_interface_set_flags (vnm, hw_if_index, 0 /* down */ );

	ipip_tunnel_restack (t);

	return /* no error */ 0;
	}

	static int
	ipip_tunnel_desc (u32 sw_if_index,
	ip46_address_t * src, ip46_address_t * dst, u8 * is_l2)
	{
	ipip_tunnel_t *t;

	t = ipip_tunnel_db_find_by_sw_if_index (sw_if_index);
	if (!t)
	return -1;

	*src = t->tunnel_src;
	*dst = t->tunnel_dst;
	*is_l2 = 0;

	return (0);
	}

	/* INDENT-OFF */
	VNET_DEVICE_CLASS(ipip_device_class) = {
	.name = "IPIP tunnel device",
	.format_device_name = format_ipip_tunnel_name,
	.format_device = format_ipip_device,
	.format_tx_trace = format_ipip_tx_trace,
	.admin_up_down_function = ipip_interface_admin_up_down,
	.ip_tun_desc = ipip_tunnel_desc,
	#ifdef SOON
	.clear counter = 0;
	#endif
	};

	VNET_HW_INTERFACE_CLASS(ipip_hw_interface_class) = {
	.name = "IPIP",
	//.format_header = format_ipip_header_with_length,
	//.unformat_header = unformat_ipip_header,
	.build_rewrite = ipip_build_rewrite,
	.update_adjacency = ipip_update_adj,
	.flags = VNET_HW_INTERFACE_CLASS_FLAG_P2P,
	};
	/* INDENT-ON */

	ipip_tunnel_t *
	ipip_tunnel_db_find (ipip_tunnel_key_t * key)
	{
	ipip_main_t *gm = &ipip_main;
	uword *p;

	p = hash_get_mem (gm->tunnel_by_key, key);
	if (!p)
	return (NULL);
	return (pool_elt_at_index (gm->tunnels, p[0]));
	}

	ipip_tunnel_t *
	ipip_tunnel_db_find_by_sw_if_index (u32 sw_if_index)
	{
	ipip_main_t *gm = &ipip_main;
	if (vec_len (gm->tunnel_index_by_sw_if_index) <= sw_if_index)
	return NULL;
	u32 ti = gm->tunnel_index_by_sw_if_index[sw_if_index];
	if (ti == ~0)
	return NULL;
	return pool_elt_at_index (gm->tunnels, ti);
	}

	void
	ipip_tunnel_db_add (ipip_tunnel_t * t, ipip_tunnel_key_t * key)
	{
	ipip_main_t *gm = &ipip_main;

	t->key = clib_mem_alloc (sizeof (*t->key));
	clib_memcpy (t->key, key, sizeof (*key));
	hash_set_mem (gm->tunnel_by_key, t->key, t->dev_instance);
	}

	void
	ipip_tunnel_db_remove (ipip_tunnel_t * t)
	{
	ipip_main_t *gm = &ipip_main;

	hash_unset_mem (gm->tunnel_by_key, t->key);
	clib_mem_free (t->key);
	t->key = NULL;
	}

	int
	ipip_add_tunnel (ipip_transport_t transport,
	u32 instance, ip46_address_t * src, ip46_address_t * dst,
	u32 fib_index, ipip_tunnel_flags_t flags,
	ip_dscp_t dscp, u32 * sw_if_indexp)
	{
	ipip_main_t *gm = &ipip_main;
	vnet_main_t *vnm = gm->vnet_main;
	ip4_main_t *im4 = &ip4_main;
	ip6_main_t *im6 = &ip6_main;
	ipip_tunnel_t *t;
	vnet_hw_interface_t *hi;
	u32 hw_if_index, sw_if_index;
	ipip_tunnel_key_t key = {.transport = transport,
	.fib_index = fib_index,
	.src = *src,
	.dst = *dst
	};
	t = ipip_tunnel_db_find (&key);
	if (t)
	{
	if (sw_if_indexp)
	sw_if_indexp[0] = t->sw_if_index;
	return VNET_API_ERROR_IF_ALREADY_EXISTS;
	}

	pool_get_aligned (gm->tunnels, t, CLIB_CACHE_LINE_BYTES);
	clib_memset (t, 0, sizeof (*t));

	/* Reconcile the real dev_instance and a possible requested instance */
	u32 t_idx = t - gm->tunnels; /* tunnel index (or instance) */
	u32 u_idx = instance; /* user specified instance */
	if (u_idx == ~0)
	u_idx = t_idx;
	if (hash_get (gm->instance_used, u_idx))
	{
	pool_put (gm->tunnels, t);
	return VNET_API_ERROR_INSTANCE_IN_USE;
	}
	hash_set (gm->instance_used, u_idx, 1);

	t->dev_instance = t_idx; /* actual */
	t->user_instance = u_idx; /* name */

	hw_if_index = vnet_register_interface (vnm, ipip_device_class.index, t_idx,
	ipip_hw_interface_class.index,
	t_idx);

	hi = vnet_get_hw_interface (vnm, hw_if_index);
	sw_if_index = hi->sw_if_index;

	t->hw_if_index = hw_if_index;
	t->fib_index = fib_index;
	t->sw_if_index = sw_if_index;
	t->dscp = dscp;
	t->flags = flags;
	t->transport = transport;

	vec_validate_init_empty (gm->tunnel_index_by_sw_if_index, sw_if_index, ~0);
	gm->tunnel_index_by_sw_if_index[sw_if_index] = t_idx;

	if (t->transport == IPIP_TRANSPORT_IP4)
	{
	vec_validate (im4->fib_index_by_sw_if_index, sw_if_index);
	hi->min_packet_bytes = 64 + sizeof (ip4_header_t);
	}
	else
	{
	vec_validate (im6->fib_index_by_sw_if_index, sw_if_index);
	hi->min_packet_bytes = 64 + sizeof (ip6_header_t);
	}

	/* Standard default ipip MTU. */
	vnet_sw_interface_set_mtu (vnm, sw_if_index, 9000);

	t->tunnel_src = *src;
	t->tunnel_dst = *dst;

	ipip_tunnel_db_add (t, &key);

	if (sw_if_indexp)
	*sw_if_indexp = sw_if_index;

	if (t->transport == IPIP_TRANSPORT_IP6 && !gm->ip6_protocol_registered)
	{
	ip6_register_protocol (IP_PROTOCOL_IP_IN_IP, ipip6_input_node.index);
	ip6_register_protocol (IP_PROTOCOL_IPV6, ipip6_input_node.index);
	gm->ip6_protocol_registered = true;
	}
	else if (t->transport == IPIP_TRANSPORT_IP4 && !gm->ip4_protocol_registered)
	{
	ip4_register_protocol (IP_PROTOCOL_IP_IN_IP, ipip4_input_node.index);
	ip4_register_protocol (IP_PROTOCOL_IPV6, ipip4_input_node.index);
	gm->ip4_protocol_registered = true;
	}
	return 0;
	}

	int
	ipip_del_tunnel (u32 sw_if_index)
	{
	ipip_main_t *gm = &ipip_main;
	vnet_main_t *vnm = gm->vnet_main;
	ipip_tunnel_t *t;


	t = ipip_tunnel_db_find_by_sw_if_index (sw_if_index);
	if (t == NULL)
	return VNET_API_ERROR_NO_SUCH_ENTRY;

	vnet_sw_interface_set_flags (vnm, sw_if_index, 0 /* down */ );
	gm->tunnel_index_by_sw_if_index[sw_if_index] = ~0;
	vnet_delete_hw_interface (vnm, t->hw_if_index);
	hash_unset (gm->instance_used, t->user_instance);
	ipip_tunnel_db_remove (t);
	pool_put (gm->tunnels, t);

	return 0;
	}

	static clib_error_t *
	ipip_init (vlib_main_t * vm)
	{
	ipip_main_t *gm = &ipip_main;

	clib_memset (gm, 0, sizeof (gm[0]));
	gm->vlib_main = vm;
	gm->vnet_main = vnet_get_main ();
	gm->tunnel_by_key =
	hash_create_mem (0, sizeof (ipip_tunnel_key_t), sizeof (uword));

	return 0;
	}

	VLIB_INIT_FUNCTION (ipip_init);

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