src/vnet/ipsec/ipsec_tun_in.c - fdio/vpp - Gitiles

 /*
  * ipsec_tun_protect_in.c : IPSec interface input node
  *
  * 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.
  */

 #include <vnet/vnet.h>
 #include <vnet/api_errno.h>
 #include <vnet/ip/ip.h>

 #include <vnet/ipsec/ipsec.h>
 #include <vnet/ipsec/esp.h>
 #include <vnet/ipsec/ipsec_io.h>
 #include <vnet/ipsec/ipsec_punt.h>
 #include <vnet/ipsec/ipsec_tun.h>
 #include <vnet/ip/ip4_input.h>

 /* Statistics (not really errors) */
 #define foreach_ipsec_tun_protect_input_error                     \
   _(RX, "good packets received")                                  \
   _(DISABLED, "ipsec packets received on disabled interface")     \
   _(NO_TUNNEL, "no matching tunnel")                              \
   _(TUNNEL_MISMATCH, "SPI-tunnel mismatch")                       \
   _(NAT_KEEPALIVE, "NAT Keepalive")                               \
   _(TOO_SHORT, "Too Short")                                       \
   _(SPI_0, "SPI 0")

 static char *ipsec_tun_protect_input_error_strings[] = {
 #define _(sym,string) string,
   foreach_ipsec_tun_protect_input_error
 #undef _
 };

 typedef enum
 {
 #define _(sym,str) IPSEC_TUN_PROTECT_INPUT_ERROR_##sym,
   foreach_ipsec_tun_protect_input_error
 #undef _
     IPSEC_TUN_PROTECT_INPUT_N_ERROR,
 } ipsec_tun_protect_input_error_t;

 typedef enum ipsec_tun_next_t_
 {
 #define _(v, s) IPSEC_TUN_PROTECT_NEXT_##v,
   foreach_ipsec_input_next
 #undef _
     IPSEC_TUN_PROTECT_NEXT_DECRYPT,
   IPSEC_TUN_PROTECT_N_NEXT,
 } ipsec_tun_next_t;

 typedef struct
 {
   union
   {
     ipsec4_tunnel_key_t key4;
     ipsec6_tunnel_key_t key6;
   };
   u8 is_ip6;
   u32 seq;
   u32 sa_index;
 } ipsec_tun_protect_input_trace_t;

 static u8 *
 format_ipsec_tun_protect_input_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 *);
   ipsec_tun_protect_input_trace_t *t =
     va_arg (*args, ipsec_tun_protect_input_trace_t *);

   if (t->is_ip6)
     s = format (s, "IPSec: %U seq %u sa %d",
 		format_ipsec6_tunnel_key, &t->key6, t->seq, t->sa_index);
   else
     s = format (s, "IPSec: %U seq %u sa %d",
 		format_ipsec4_tunnel_key, &t->key4, t->seq, t->sa_index);
   return s;
 }

 always_inline u16
 ipsec_ip4_if_no_tunnel (vlib_node_runtime_t * node,
 			vlib_buffer_t * b,
 			const esp_header_t * esp, const ip4_header_t * ip4)
 {
   if (PREDICT_FALSE (0 == esp->spi))
     {
       b->error = node->errors[IPSEC_TUN_PROTECT_INPUT_ERROR_SPI_0];
       b->punt_reason = ipsec_punt_reason[(ip4->protocol == IP_PROTOCOL_UDP ?
 					  IPSEC_PUNT_IP4_SPI_UDP_0 :
 					  IPSEC_PUNT_IP4_NO_SUCH_TUNNEL)];
     }
   else
     {
       b->error = node->errors[IPSEC_TUN_PROTECT_INPUT_ERROR_NO_TUNNEL];
       b->punt_reason = ipsec_punt_reason[IPSEC_PUNT_IP4_NO_SUCH_TUNNEL];
     }
   return IPSEC_INPUT_NEXT_PUNT;
 }

 always_inline u16
 ipsec_ip6_if_no_tunnel (vlib_node_runtime_t * node,
 			vlib_buffer_t * b, const esp_header_t * esp)
 {
   b->error = node->errors[IPSEC_TUN_PROTECT_INPUT_ERROR_NO_TUNNEL];
   b->punt_reason = ipsec_punt_reason[IPSEC_PUNT_IP6_NO_SUCH_TUNNEL];

   return (IPSEC_INPUT_NEXT_PUNT);
 }

 always_inline uword
 ipsec_tun_protect_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
 				vlib_frame_t * from_frame, int is_ip6)
 {
   ipsec_main_t *im = &ipsec_main;
   vnet_main_t *vnm = im->vnet_main;
   vnet_interface_main_t *vim = &vnm->interface_main;

   int is_trace = node->flags & VLIB_NODE_FLAG_TRACE;
   u32 thread_index = vm->thread_index;

   u32 n_left_from, *from;
   u16 nexts[VLIB_FRAME_SIZE], *next;
   vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;

   from = vlib_frame_vector_args (from_frame);
   n_left_from = from_frame->n_vectors;

   vlib_get_buffers (vm, from, bufs, n_left_from);
   b = bufs;
   next = nexts;

   clib_memset_u16 (nexts, im->esp4_decrypt_next_index, n_left_from);

   u64 n_bytes = 0, n_packets = 0;
   u32 n_disabled = 0, n_no_tunnel = 0;

   u32 last_sw_if_index = ~0;
   ipsec_tun_lkup_result_t last_result = {
     .tun_index = ~0
   };
   ipsec4_tunnel_key_t last_key4;
   ipsec6_tunnel_key_t last_key6;

   vlib_combined_counter_main_t *rx_counter;
   vlib_combined_counter_main_t *drop_counter;
   ipsec_tun_protect_t *itp0;

   if (is_ip6)
     clib_memset (&last_key6, 0xff, sizeof (last_key6));
   else
     last_key4.as_u64 = ~0;

   rx_counter = vim->combined_sw_if_counters + VNET_INTERFACE_COUNTER_RX;
   drop_counter = vim->combined_sw_if_counters + VNET_INTERFACE_COUNTER_DROP;

   while (n_left_from > 0)
     {
       u32 sw_if_index0, len0, hdr_sz0;
       ipsec_tun_lkup_result_t itr0;
       ipsec4_tunnel_key_t key40;
       ipsec6_tunnel_key_t key60;
       ip4_header_t *ip40;
       ip6_header_t *ip60;
       esp_header_t *esp0;
       u16 buf_rewind0;

       ip40 =
 	(ip4_header_t *) (b[0]->data + vnet_buffer (b[0])->l3_hdr_offset);

       if (is_ip6)
 	{
 	  ip60 = (ip6_header_t *) ip40;
 	  esp0 = (esp_header_t *) (ip60 + 1);
 	  hdr_sz0 = sizeof (ip6_header_t);
 	}
       else
 	{
 	  /* NAT UDP port 4500 case, don't advance any more */
 	  if (ip40->protocol == IP_PROTOCOL_UDP)
 	    {
 	      esp0 =
 		(esp_header_t *) ((u8 *) ip40 + ip4_header_bytes (ip40) +
 				  sizeof (udp_header_t));
 	      hdr_sz0 = 0;
 	      buf_rewind0 = ip4_header_bytes (ip40) + sizeof (udp_header_t);
 	    }
 	  else
 	    {
 	      esp0 = (esp_header_t *) ((u8 *) ip40 + ip4_header_bytes (ip40));
 	      buf_rewind0 = hdr_sz0 = ip4_header_bytes (ip40);
 	    }
 	}

       /* stats for the tunnel include all the data after the IP header
          just like a norml IP-IP tunnel */
       vlib_buffer_advance (b[0], hdr_sz0);
       len0 = vlib_buffer_length_in_chain (vm, b[0]);

       if (len0 < sizeof (esp_header_t))
 	{
 	  if (esp0->spi_bytes[0] == 0xff)
 	    b[0]->error =
 	      node->errors[IPSEC_TUN_PROTECT_INPUT_ERROR_NAT_KEEPALIVE];
 	  else
 	    b[0]->error =
 	      node->errors[IPSEC_TUN_PROTECT_INPUT_ERROR_TOO_SHORT];

 	  next[0] = IPSEC_INPUT_NEXT_DROP;
 	  goto trace00;
 	}

       if (is_ip6)
 	{
 	  key60.remote_ip = ip60->src_address;
 	  key60.spi = esp0->spi;

 	  if (memcmp (&key60, &last_key6, sizeof (last_key6)) == 0)
 	    {
 	      itr0 = last_result;
 	    }
 	  else
 	    {
 	      uword *p = hash_get_mem (im->tun6_protect_by_key, &key60);
 	      if (p)
 		{
 		  itr0.as_u64 = p[0];
 		  last_result = itr0;
 		  clib_memcpy_fast (&last_key6, &key60, sizeof (key60));
 		}
 	      else
 		{
 		  next[0] = ipsec_ip6_if_no_tunnel (node, b[0], esp0);
 		  n_no_tunnel++;
 		  goto trace00;
 		}
 	    }
 	}
       else
 	{
 	  key40.remote_ip = ip40->src_address;
 	  key40.spi = esp0->spi;

 	  if (key40.as_u64 == last_key4.as_u64)
 	    {
 	      itr0 = last_result;
 	    }
 	  else
 	    {
 	      uword *p = hash_get (im->tun4_protect_by_key, key40.as_u64);
 	      if (p)
 		{
 		  itr0.as_u64 = p[0];
 		  last_result = itr0;
 		  last_key4.as_u64 = key40.as_u64;
 		}
 	      else
 		{
 		  next[0] = ipsec_ip4_if_no_tunnel (node, b[0], esp0, ip40);
 		  vlib_buffer_advance (b[0], -buf_rewind0);
 		  n_no_tunnel++;
 		  goto trace00;
 		}
 	    }
 	}

       itp0 = pool_elt_at_index (ipsec_protect_pool, itr0.tun_index);
       vnet_buffer (b[0])->ipsec.sad_index = itr0.sa_index;
       vnet_buffer (b[0])->ipsec.protect_index = itr0.tun_index;

       sw_if_index0 = itp0->itp_sw_if_index;
       vnet_buffer (b[0])->sw_if_index[VLIB_RX] = sw_if_index0;

       if (PREDICT_FALSE (!vnet_sw_interface_is_admin_up (vnm, sw_if_index0)))
 	{
 	  vlib_increment_combined_counter
 	    (drop_counter, thread_index, sw_if_index0, 1, len0);
 	  n_disabled++;
 	  b[0]->error = node->errors[IPSEC_TUN_PROTECT_INPUT_ERROR_DISABLED];
 	  next[0] = IPSEC_INPUT_NEXT_DROP;
 	  goto trace00;
 	}
       else
 	{
 	  if (PREDICT_TRUE (sw_if_index0 == last_sw_if_index))
 	    {
 	      n_packets++;
 	      n_bytes += len0;
 	    }
 	  else
 	    {
 	      if (n_packets && !(itp0->itp_flags & IPSEC_PROTECT_ENCAPED))
 		{
 		  vlib_increment_combined_counter
 		    (rx_counter, thread_index, last_sw_if_index,
 		     n_packets, n_bytes);
 		}

 	      last_sw_if_index = sw_if_index0;
 	      n_packets = 1;
 	      n_bytes = len0;
 	    }

 	  /*
 	   * compare the packet's outer IP headers to that of the tunnels
 	   */
 	  if (is_ip6)
 	    {
 	      if (PREDICT_FALSE
 		  (!ip46_address_is_equal_v6
 		   (&itp0->itp_crypto.dst, &ip60->src_address)
 		   || !ip46_address_is_equal_v6 (&itp0->itp_crypto.src,
 						 &ip60->dst_address)))
 		{
 		  b[0]->error =
 		    node->errors
 		    [IPSEC_TUN_PROTECT_INPUT_ERROR_TUNNEL_MISMATCH];
 		  next[0] = IPSEC_INPUT_NEXT_DROP;
 		  goto trace00;
 		}
 	    }
 	  else
 	    {
 	      if (PREDICT_FALSE
 		  (!ip46_address_is_equal_v4
 		   (&itp0->itp_crypto.dst, &ip40->src_address)
 		   || !ip46_address_is_equal_v4 (&itp0->itp_crypto.src,
 						 &ip40->dst_address)))
 		{
 		  b[0]->error =
 		    node->errors
 		    [IPSEC_TUN_PROTECT_INPUT_ERROR_TUNNEL_MISMATCH];
 		  next[0] = IPSEC_INPUT_NEXT_DROP;
 		  goto trace00;
 		}
 	    }

 	  /*
 	   * There are two encap possibilities
 	   * 1) the tunnel and ths SA are prodiving encap, i.e. it's
 	   *   MAC | SA-IP | TUN-IP | ESP | PAYLOAD
 	   * implying the SA is in tunnel mode (on a tunnel interface)
 	   * 2) only the tunnel provides encap
 	   *   MAC | TUN-IP | ESP | PAYLOAD
 	   * implying the SA is in transport mode.
 	   *
 	   * For 2) we need only strip the tunnel encap and we're good.
 	   *  since the tunnel and crypto ecnap (int the tun=protect
 	   * object) are the same and we verified above that these match
 	   * for 1) we need to strip the SA-IP outer headers, to
 	   * reveal the tunnel IP and then check that this matches
 	   * the configured tunnel. this we can;t do here since it
 	   * involves a lookup in the per-tunnel-type DB - so ship
 	   * the packet to the tunnel-types provided node to do that
 	   */
 	  next[0] = IPSEC_TUN_PROTECT_NEXT_DECRYPT;
 	}
     trace00:
       if (PREDICT_FALSE (is_trace))
 	{
 	  if (b[0]->flags & VLIB_BUFFER_IS_TRACED)
 	    {
 	      ipsec_tun_protect_input_trace_t *tr =
 		vlib_add_trace (vm, node, b[0], sizeof (*tr));
 	      if (is_ip6)
 		clib_memcpy (&tr->key6, &key60, sizeof (tr->key6));
 	      else
 		clib_memcpy (&tr->key4, &key40, sizeof (tr->key4));
 	      tr->is_ip6 = is_ip6;
 	      tr->seq = (len0 >= sizeof (*esp0) ?
 			 clib_host_to_net_u32 (esp0->seq) : ~0);
 	      tr->sa_index = vnet_buffer (b[0])->ipsec.sad_index;
 	    }
 	}

       /* next */
       b += 1;
       next += 1;
       n_left_from -= 1;
     }

   if (n_packets && !(itp0->itp_flags & IPSEC_PROTECT_ENCAPED))
     {
       vlib_increment_combined_counter (rx_counter,
 				       thread_index,
 				       last_sw_if_index, n_packets, n_bytes);
     }

   vlib_node_increment_counter (vm, node->node_index,
 			       IPSEC_TUN_PROTECT_INPUT_ERROR_RX,
 			       from_frame->n_vectors - (n_disabled +
 							n_no_tunnel));

   vlib_buffer_enqueue_to_next (vm, node, from, nexts, from_frame->n_vectors);

   return from_frame->n_vectors;
 }

 VLIB_NODE_FN (ipsec4_tun_input_node) (vlib_main_t * vm,
 				      vlib_node_runtime_t * node,
 				      vlib_frame_t * from_frame)
 {
   return ipsec_tun_protect_input_inline (vm, node, from_frame,
 					 0 /* is_ip6 */ );
 }

 /* *INDENT-OFF* */
 VLIB_REGISTER_NODE (ipsec4_tun_input_node) = {
   .name = "ipsec4-tun-input",
   .vector_size = sizeof (u32),
   .format_trace = format_ipsec_tun_protect_input_trace,
   .type = VLIB_NODE_TYPE_INTERNAL,
   .n_errors = ARRAY_LEN(ipsec_tun_protect_input_error_strings),
   .error_strings = ipsec_tun_protect_input_error_strings,
   .n_next_nodes = IPSEC_TUN_PROTECT_N_NEXT,
   .next_nodes = {
     [IPSEC_TUN_PROTECT_NEXT_DROP] = "ip4-drop",
     [IPSEC_TUN_PROTECT_NEXT_PUNT] = "punt-dispatch",
     [IPSEC_TUN_PROTECT_NEXT_DECRYPT] = "esp4-decrypt-tun",
   }
 };
 /* *INDENT-ON* */

 VLIB_NODE_FN (ipsec6_tun_input_node) (vlib_main_t * vm,
 				      vlib_node_runtime_t * node,
 				      vlib_frame_t * from_frame)
 {
   return ipsec_tun_protect_input_inline (vm, node, from_frame,
 					 1 /* is_ip6 */ );
 }

 /* *INDENT-OFF* */
 VLIB_REGISTER_NODE (ipsec6_tun_input_node) = {
   .name = "ipsec6-tun-input",
   .vector_size = sizeof (u32),
   .format_trace = format_ipsec_tun_protect_input_trace,
   .type = VLIB_NODE_TYPE_INTERNAL,
   .n_errors = ARRAY_LEN(ipsec_tun_protect_input_error_strings),
   .error_strings = ipsec_tun_protect_input_error_strings,
   .n_next_nodes = IPSEC_TUN_PROTECT_N_NEXT,
   .next_nodes = {
     [IPSEC_TUN_PROTECT_NEXT_DROP] = "ip6-drop",
     [IPSEC_TUN_PROTECT_NEXT_PUNT] = "punt-dispatch",
     [IPSEC_TUN_PROTECT_NEXT_DECRYPT] = "esp6-decrypt-tun",
   }
 };
 /* *INDENT-ON* */

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

	#include <vnet/vnet.h>
	#include <vnet/api_errno.h>
	#include <vnet/ip/ip.h>

	#include <vnet/ipsec/ipsec.h>
	#include <vnet/ipsec/esp.h>
	#include <vnet/ipsec/ipsec_io.h>
	#include <vnet/ipsec/ipsec_punt.h>
	#include <vnet/ipsec/ipsec_tun.h>
	#include <vnet/ip/ip4_input.h>

	/* Statistics (not really errors) */
	#define foreach_ipsec_tun_protect_input_error \
	_(RX, "good packets received") \
	_(DISABLED, "ipsec packets received on disabled interface") \
	_(NO_TUNNEL, "no matching tunnel") \
	_(TUNNEL_MISMATCH, "SPI-tunnel mismatch") \
	_(NAT_KEEPALIVE, "NAT Keepalive") \
	_(TOO_SHORT, "Too Short") \
	_(SPI_0, "SPI 0")

	static char *ipsec_tun_protect_input_error_strings[] = {
	#define _(sym,string) string,
	foreach_ipsec_tun_protect_input_error
	#undef _
	};

	typedef enum
	{
	#define _(sym,str) IPSEC_TUN_PROTECT_INPUT_ERROR_##sym,
	foreach_ipsec_tun_protect_input_error
	#undef _
	IPSEC_TUN_PROTECT_INPUT_N_ERROR,
	} ipsec_tun_protect_input_error_t;

	typedef enum ipsec_tun_next_t_
	{
	#define _(v, s) IPSEC_TUN_PROTECT_NEXT_##v,
	foreach_ipsec_input_next
	#undef _
	IPSEC_TUN_PROTECT_NEXT_DECRYPT,
	IPSEC_TUN_PROTECT_N_NEXT,
	} ipsec_tun_next_t;

	typedef struct
	{
	union
	{
	ipsec4_tunnel_key_t key4;
	ipsec6_tunnel_key_t key6;
	};
	u8 is_ip6;
	u32 seq;
	u32 sa_index;
	} ipsec_tun_protect_input_trace_t;

	static u8 *
	format_ipsec_tun_protect_input_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 );
	ipsec_tun_protect_input_trace_t *t =
	va_arg (args, ipsec_tun_protect_input_trace_t );

	if (t->is_ip6)
	s = format (s, "IPSec: %U seq %u sa %d",
	format_ipsec6_tunnel_key, &t->key6, t->seq, t->sa_index);
	else
	s = format (s, "IPSec: %U seq %u sa %d",
	format_ipsec4_tunnel_key, &t->key4, t->seq, t->sa_index);
	return s;
	}

	always_inline u16
	ipsec_ip4_if_no_tunnel (vlib_node_runtime_t * node,
	vlib_buffer_t * b,
	const esp_header_t * esp, const ip4_header_t * ip4)
	{
	if (PREDICT_FALSE (0 == esp->spi))
	{
	b->error = node->errors[IPSEC_TUN_PROTECT_INPUT_ERROR_SPI_0];
	b->punt_reason = ipsec_punt_reason[(ip4->protocol == IP_PROTOCOL_UDP ?
	IPSEC_PUNT_IP4_SPI_UDP_0 :
	IPSEC_PUNT_IP4_NO_SUCH_TUNNEL)];
	}
	else
	{
	b->error = node->errors[IPSEC_TUN_PROTECT_INPUT_ERROR_NO_TUNNEL];
	b->punt_reason = ipsec_punt_reason[IPSEC_PUNT_IP4_NO_SUCH_TUNNEL];
	}
	return IPSEC_INPUT_NEXT_PUNT;
	}

	always_inline u16
	ipsec_ip6_if_no_tunnel (vlib_node_runtime_t * node,
	vlib_buffer_t * b, const esp_header_t * esp)
	{
	b->error = node->errors[IPSEC_TUN_PROTECT_INPUT_ERROR_NO_TUNNEL];
	b->punt_reason = ipsec_punt_reason[IPSEC_PUNT_IP6_NO_SUCH_TUNNEL];

	return (IPSEC_INPUT_NEXT_PUNT);
	}

	always_inline uword
	ipsec_tun_protect_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
	vlib_frame_t * from_frame, int is_ip6)
	{
	ipsec_main_t *im = &ipsec_main;
	vnet_main_t *vnm = im->vnet_main;
	vnet_interface_main_t *vim = &vnm->interface_main;

	int is_trace = node->flags & VLIB_NODE_FLAG_TRACE;
	u32 thread_index = vm->thread_index;

	u32 n_left_from, *from;
	u16 nexts[VLIB_FRAME_SIZE], *next;
	vlib_buffer_t bufs[VLIB_FRAME_SIZE], *b;

	from = vlib_frame_vector_args (from_frame);
	n_left_from = from_frame->n_vectors;

	vlib_get_buffers (vm, from, bufs, n_left_from);
	b = bufs;
	next = nexts;

	clib_memset_u16 (nexts, im->esp4_decrypt_next_index, n_left_from);

	u64 n_bytes = 0, n_packets = 0;
	u32 n_disabled = 0, n_no_tunnel = 0;

	u32 last_sw_if_index = ~0;
	ipsec_tun_lkup_result_t last_result = {
	.tun_index = ~0
	};
	ipsec4_tunnel_key_t last_key4;
	ipsec6_tunnel_key_t last_key6;

	vlib_combined_counter_main_t *rx_counter;
	vlib_combined_counter_main_t *drop_counter;
	ipsec_tun_protect_t *itp0;

	if (is_ip6)
	clib_memset (&last_key6, 0xff, sizeof (last_key6));
	else
	last_key4.as_u64 = ~0;

	rx_counter = vim->combined_sw_if_counters + VNET_INTERFACE_COUNTER_RX;
	drop_counter = vim->combined_sw_if_counters + VNET_INTERFACE_COUNTER_DROP;

	while (n_left_from > 0)
	{
	u32 sw_if_index0, len0, hdr_sz0;
	ipsec_tun_lkup_result_t itr0;
	ipsec4_tunnel_key_t key40;
	ipsec6_tunnel_key_t key60;
	ip4_header_t *ip40;
	ip6_header_t *ip60;
	esp_header_t *esp0;
	u16 buf_rewind0;

	ip40 =
	(ip4_header_t *) (b[0]->data + vnet_buffer (b[0])->l3_hdr_offset);

	if (is_ip6)
	{
	ip60 = (ip6_header_t *) ip40;
	esp0 = (esp_header_t *) (ip60 + 1);
	hdr_sz0 = sizeof (ip6_header_t);
	}
	else
	{
	/* NAT UDP port 4500 case, don't advance any more */
	if (ip40->protocol == IP_PROTOCOL_UDP)
	{
	esp0 =
	(esp_header_t ) ((u8 ) ip40 + ip4_header_bytes (ip40) +
	sizeof (udp_header_t));
	hdr_sz0 = 0;
	buf_rewind0 = ip4_header_bytes (ip40) + sizeof (udp_header_t);
	}
	else
	{
	esp0 = (esp_header_t ) ((u8 ) ip40 + ip4_header_bytes (ip40));
	buf_rewind0 = hdr_sz0 = ip4_header_bytes (ip40);
	}
	}

	/* stats for the tunnel include all the data after the IP header
	just like a norml IP-IP tunnel */
	vlib_buffer_advance (b[0], hdr_sz0);
	len0 = vlib_buffer_length_in_chain (vm, b[0]);

	if (len0 < sizeof (esp_header_t))
	{
	if (esp0->spi_bytes[0] == 0xff)
	b[0]->error =
	node->errors[IPSEC_TUN_PROTECT_INPUT_ERROR_NAT_KEEPALIVE];
	else
	b[0]->error =
	node->errors[IPSEC_TUN_PROTECT_INPUT_ERROR_TOO_SHORT];

	next[0] = IPSEC_INPUT_NEXT_DROP;
	goto trace00;
	}

	if (is_ip6)
	{
	key60.remote_ip = ip60->src_address;
	key60.spi = esp0->spi;

	if (memcmp (&key60, &last_key6, sizeof (last_key6)) == 0)
	{
	itr0 = last_result;
	}
	else
	{
	uword *p = hash_get_mem (im->tun6_protect_by_key, &key60);
	if (p)
	{
	itr0.as_u64 = p[0];
	last_result = itr0;
	clib_memcpy_fast (&last_key6, &key60, sizeof (key60));
	}
	else
	{
	next[0] = ipsec_ip6_if_no_tunnel (node, b[0], esp0);
	n_no_tunnel++;
	goto trace00;
	}
	}
	}
	else
	{
	key40.remote_ip = ip40->src_address;
	key40.spi = esp0->spi;

	if (key40.as_u64 == last_key4.as_u64)
	{
	itr0 = last_result;
	}
	else
	{
	uword *p = hash_get (im->tun4_protect_by_key, key40.as_u64);
	if (p)
	{
	itr0.as_u64 = p[0];
	last_result = itr0;
	last_key4.as_u64 = key40.as_u64;
	}
	else
	{
	next[0] = ipsec_ip4_if_no_tunnel (node, b[0], esp0, ip40);
	vlib_buffer_advance (b[0], -buf_rewind0);
	n_no_tunnel++;
	goto trace00;
	}
	}
	}

	itp0 = pool_elt_at_index (ipsec_protect_pool, itr0.tun_index);
	vnet_buffer (b[0])->ipsec.sad_index = itr0.sa_index;
	vnet_buffer (b[0])->ipsec.protect_index = itr0.tun_index;

	sw_if_index0 = itp0->itp_sw_if_index;
	vnet_buffer (b[0])->sw_if_index[VLIB_RX] = sw_if_index0;

	if (PREDICT_FALSE (!vnet_sw_interface_is_admin_up (vnm, sw_if_index0)))
	{
	vlib_increment_combined_counter
	(drop_counter, thread_index, sw_if_index0, 1, len0);
	n_disabled++;
	b[0]->error = node->errors[IPSEC_TUN_PROTECT_INPUT_ERROR_DISABLED];
	next[0] = IPSEC_INPUT_NEXT_DROP;
	goto trace00;
	}
	else
	{
	if (PREDICT_TRUE (sw_if_index0 == last_sw_if_index))
	{
	n_packets++;
	n_bytes += len0;
	}
	else
	{
	if (n_packets && !(itp0->itp_flags & IPSEC_PROTECT_ENCAPED))
	{
	vlib_increment_combined_counter
	(rx_counter, thread_index, last_sw_if_index,
	n_packets, n_bytes);
	}

	last_sw_if_index = sw_if_index0;
	n_packets = 1;
	n_bytes = len0;
	}

	/*
	* compare the packet's outer IP headers to that of the tunnels
	*/
	if (is_ip6)
	{
	if (PREDICT_FALSE
	(!ip46_address_is_equal_v6
	(&itp0->itp_crypto.dst, &ip60->src_address)
	\|\| !ip46_address_is_equal_v6 (&itp0->itp_crypto.src,
	&ip60->dst_address)))
	{
	b[0]->error =
	node->errors
	[IPSEC_TUN_PROTECT_INPUT_ERROR_TUNNEL_MISMATCH];
	next[0] = IPSEC_INPUT_NEXT_DROP;
	goto trace00;
	}
	}
	else
	{
	if (PREDICT_FALSE
	(!ip46_address_is_equal_v4
	(&itp0->itp_crypto.dst, &ip40->src_address)
	\|\| !ip46_address_is_equal_v4 (&itp0->itp_crypto.src,
	&ip40->dst_address)))
	{
	b[0]->error =
	node->errors
	[IPSEC_TUN_PROTECT_INPUT_ERROR_TUNNEL_MISMATCH];
	next[0] = IPSEC_INPUT_NEXT_DROP;
	goto trace00;
	}
	}

	/*
	* There are two encap possibilities
	* 1) the tunnel and ths SA are prodiving encap, i.e. it's
	* MAC \| SA-IP \| TUN-IP \| ESP \| PAYLOAD
	* implying the SA is in tunnel mode (on a tunnel interface)
	* 2) only the tunnel provides encap
	* MAC \| TUN-IP \| ESP \| PAYLOAD
	* implying the SA is in transport mode.
	*
	* For 2) we need only strip the tunnel encap and we're good.
	* since the tunnel and crypto ecnap (int the tun=protect
	* object) are the same and we verified above that these match
	* for 1) we need to strip the SA-IP outer headers, to
	* reveal the tunnel IP and then check that this matches
	* the configured tunnel. this we can;t do here since it
	* involves a lookup in the per-tunnel-type DB - so ship
	* the packet to the tunnel-types provided node to do that
	*/
	next[0] = IPSEC_TUN_PROTECT_NEXT_DECRYPT;
	}
	trace00:
	if (PREDICT_FALSE (is_trace))
	{
	if (b[0]->flags & VLIB_BUFFER_IS_TRACED)
	{
	ipsec_tun_protect_input_trace_t *tr =
	vlib_add_trace (vm, node, b[0], sizeof (*tr));
	if (is_ip6)
	clib_memcpy (&tr->key6, &key60, sizeof (tr->key6));
	else
	clib_memcpy (&tr->key4, &key40, sizeof (tr->key4));
	tr->is_ip6 = is_ip6;
	tr->seq = (len0 >= sizeof (*esp0) ?
	clib_host_to_net_u32 (esp0->seq) : ~0);
	tr->sa_index = vnet_buffer (b[0])->ipsec.sad_index;
	}
	}

	/* next */
	b += 1;
	next += 1;
	n_left_from -= 1;
	}

	if (n_packets && !(itp0->itp_flags & IPSEC_PROTECT_ENCAPED))
	{
	vlib_increment_combined_counter (rx_counter,
	thread_index,
	last_sw_if_index, n_packets, n_bytes);
	}

	vlib_node_increment_counter (vm, node->node_index,
	IPSEC_TUN_PROTECT_INPUT_ERROR_RX,
	from_frame->n_vectors - (n_disabled +
	n_no_tunnel));

	vlib_buffer_enqueue_to_next (vm, node, from, nexts, from_frame->n_vectors);

	return from_frame->n_vectors;
	}

	VLIB_NODE_FN (ipsec4_tun_input_node) (vlib_main_t * vm,
	vlib_node_runtime_t * node,
	vlib_frame_t * from_frame)
	{
	return ipsec_tun_protect_input_inline (vm, node, from_frame,
	0 /* is_ip6 */ );
	}

	/* INDENT-OFF */
	VLIB_REGISTER_NODE (ipsec4_tun_input_node) = {
	.name = "ipsec4-tun-input",
	.vector_size = sizeof (u32),
	.format_trace = format_ipsec_tun_protect_input_trace,
	.type = VLIB_NODE_TYPE_INTERNAL,
	.n_errors = ARRAY_LEN(ipsec_tun_protect_input_error_strings),
	.error_strings = ipsec_tun_protect_input_error_strings,
	.n_next_nodes = IPSEC_TUN_PROTECT_N_NEXT,
	.next_nodes = {
	[IPSEC_TUN_PROTECT_NEXT_DROP] = "ip4-drop",
	[IPSEC_TUN_PROTECT_NEXT_PUNT] = "punt-dispatch",
	[IPSEC_TUN_PROTECT_NEXT_DECRYPT] = "esp4-decrypt-tun",
	}
	};
	/* INDENT-ON */

	VLIB_NODE_FN (ipsec6_tun_input_node) (vlib_main_t * vm,
	vlib_node_runtime_t * node,
	vlib_frame_t * from_frame)
	{
	return ipsec_tun_protect_input_inline (vm, node, from_frame,
	1 /* is_ip6 */ );
	}

	/* INDENT-OFF */
	VLIB_REGISTER_NODE (ipsec6_tun_input_node) = {
	.name = "ipsec6-tun-input",
	.vector_size = sizeof (u32),
	.format_trace = format_ipsec_tun_protect_input_trace,
	.type = VLIB_NODE_TYPE_INTERNAL,
	.n_errors = ARRAY_LEN(ipsec_tun_protect_input_error_strings),
	.error_strings = ipsec_tun_protect_input_error_strings,
	.n_next_nodes = IPSEC_TUN_PROTECT_N_NEXT,
	.next_nodes = {
	[IPSEC_TUN_PROTECT_NEXT_DROP] = "ip6-drop",
	[IPSEC_TUN_PROTECT_NEXT_PUNT] = "punt-dispatch",
	[IPSEC_TUN_PROTECT_NEXT_DECRYPT] = "esp6-decrypt-tun",
	}
	};
	/* INDENT-ON */

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