src/vnet/udp/udp_local.c - fdio/vpp - Gitiles

 /*
  * node.c: udp packet processing
  *
  * Copyright (c) 2013-2019 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 <vlib/vlib.h>
 #include <vnet/pg/pg.h>
 #include <vnet/udp/udp.h>
 #include <vnet/udp/udp_packet.h>
 #include <vppinfra/sparse_vec.h>

 typedef enum
 {
   UDP_LOCAL_NEXT_PUNT,
   UDP_LOCAL_NEXT_DROP,
   UDP_LOCAL_NEXT_ICMP,
   UDP_LOCAL_N_NEXT
 } udp_local_next_t;

 typedef struct
 {
   u16 src_port;
   u16 dst_port;
   u8 bound;
 } udp_local_rx_trace_t;

 #define UDP_NO_NODE_SET ((u16) ~0)

 #ifndef CLIB_MARCH_VARIANT
 u8 *
 format_udp_rx_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 *);
   udp_local_rx_trace_t *t = va_arg (*args, udp_local_rx_trace_t *);

   s = format (s, "UDP: src-port %d dst-port %d%s",
 	      clib_net_to_host_u16 (t->src_port),
 	      clib_net_to_host_u16 (t->dst_port),
 	      t->bound ? "" : " (no listener)");
   return s;
 }
 #endif /* CLIB_MARCH_VARIANT */

 always_inline uword
 udp46_local_inline (vlib_main_t * vm,
 		    vlib_node_runtime_t * node,
 		    vlib_frame_t * from_frame, int is_ip4)
 {
   udp_main_t *um = &udp_main;
   __attribute__ ((unused)) u32 n_left_from, next_index, *from, *to_next;
   word n_no_listener = 0;
   u8 punt_unknown = is_ip4 ? um->punt_unknown4 : um->punt_unknown6;
   u16 *next_by_dst_port = (is_ip4 ?
 			   um->next_by_dst_port4 : um->next_by_dst_port6);
   from = vlib_frame_vector_args (from_frame);
   n_left_from = 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 >= 4 && n_left_to_next >= 2)
 	{
 	  u32 bi0, bi1;
 	  vlib_buffer_t *b0, *b1;
 	  udp_header_t *h0 = 0, *h1 = 0;
 	  u32 i0, i1, dst_port0, dst_port1;
 	  u32 advance0, advance1;
 	  u32 error0, next0, error1, next1;

 	  /* Prefetch next iteration. */
 	  {
 	    vlib_buffer_t *p2, *p3;

 	    p2 = vlib_get_buffer (vm, from[2]);
 	    p3 = vlib_get_buffer (vm, from[3]);

 	    vlib_prefetch_buffer_header (p2, LOAD);
 	    vlib_prefetch_buffer_header (p3, LOAD);

 	    CLIB_PREFETCH (p2->data, sizeof (h0[0]), LOAD);
 	    CLIB_PREFETCH (p3->data, sizeof (h1[0]), LOAD);
 	  }

 	  bi0 = from[0];
 	  bi1 = from[1];
 	  to_next[0] = bi0;
 	  to_next[1] = bi1;
 	  from += 2;
 	  to_next += 2;
 	  n_left_to_next -= 2;
 	  n_left_from -= 2;

 	  b0 = vlib_get_buffer (vm, bi0);
 	  b1 = vlib_get_buffer (vm, bi1);

 	  /* ip4/6_local hands us the ip header, not the udp header */
 	  if (is_ip4)
 	    {
 	      advance0 = sizeof (ip4_header_t);
 	      advance1 = sizeof (ip4_header_t);
 	    }
 	  else
 	    {
 	      advance0 = sizeof (ip6_header_t);
 	      advance1 = sizeof (ip6_header_t);
 	    }

 	  if (PREDICT_FALSE (b0->current_length < advance0 + sizeof (*h0)))
 	    {
 	      error0 = UDP_ERROR_LENGTH_ERROR;
 	      next0 = UDP_LOCAL_NEXT_DROP;
 	    }
 	  else
 	    {
 	      vlib_buffer_advance (b0, advance0);
 	      h0 = vlib_buffer_get_current (b0);
 	      error0 = UDP_ERROR_NONE;
 	      next0 = UDP_LOCAL_NEXT_PUNT;
 	      if (PREDICT_FALSE (clib_net_to_host_u16 (h0->length) >
 				 vlib_buffer_length_in_chain (vm, b0)))
 		{
 		  error0 = UDP_ERROR_LENGTH_ERROR;
 		  next0 = UDP_LOCAL_NEXT_DROP;
 		}
 	    }

 	  if (PREDICT_FALSE (b1->current_length < advance1 + sizeof (*h1)))
 	    {
 	      error1 = UDP_ERROR_LENGTH_ERROR;
 	      next1 = UDP_LOCAL_NEXT_DROP;
 	    }
 	  else
 	    {
 	      vlib_buffer_advance (b1, advance1);
 	      h1 = vlib_buffer_get_current (b1);
 	      error1 = UDP_ERROR_NONE;
 	      next1 = UDP_LOCAL_NEXT_PUNT;
 	      if (PREDICT_FALSE (clib_net_to_host_u16 (h1->length) >
 				 vlib_buffer_length_in_chain (vm, b1)))
 		{
 		  error1 = UDP_ERROR_LENGTH_ERROR;
 		  next1 = UDP_LOCAL_NEXT_DROP;
 		}
 	    }

 	  /* Index sparse array with network byte order. */
 	  dst_port0 = (error0 == 0) ? h0->dst_port : 0;
 	  dst_port1 = (error1 == 0) ? h1->dst_port : 0;
 	  sparse_vec_index2 (next_by_dst_port, dst_port0, dst_port1, &i0,
 			     &i1);
 	  next0 = (error0 == 0) ? vec_elt (next_by_dst_port, i0) : next0;
 	  next1 = (error1 == 0) ? vec_elt (next_by_dst_port, i1) : next1;

 	  if (PREDICT_FALSE (i0 == SPARSE_VEC_INVALID_INDEX ||
 			     next0 == UDP_NO_NODE_SET))
 	    {
 	      // move the pointer back so icmp-error can find the
 	      // ip packet header
 	      vlib_buffer_advance (b0, -(word) advance0);

 	      if (PREDICT_FALSE (punt_unknown))
 		{
 		  b0->error = node->errors[UDP_ERROR_PUNT];
 		  next0 = UDP_LOCAL_NEXT_PUNT;
 		}
 	      else if (is_ip4)
 		{
 		  icmp4_error_set_vnet_buffer (b0,
 					       ICMP4_destination_unreachable,
 					       ICMP4_destination_unreachable_port_unreachable,
 					       0);
 		  next0 = UDP_LOCAL_NEXT_ICMP;
 		  n_no_listener++;
 		}
 	      else
 		{
 		  icmp6_error_set_vnet_buffer (b0,
 					       ICMP6_destination_unreachable,
 					       ICMP6_destination_unreachable_port_unreachable,
 					       0);
 		  next0 = UDP_LOCAL_NEXT_ICMP;
 		  n_no_listener++;
 		}
 	    }
 	  else
 	    {
 	      b0->error = node->errors[UDP_ERROR_NONE];
 	      // advance to the payload
 	      vlib_buffer_advance (b0, sizeof (*h0));
 	    }

 	  if (PREDICT_FALSE (i1 == SPARSE_VEC_INVALID_INDEX ||
 			     next1 == UDP_NO_NODE_SET))
 	    {
 	      // move the pointer back so icmp-error can find the
 	      // ip packet header
 	      vlib_buffer_advance (b1, -(word) advance1);

 	      if (PREDICT_FALSE (punt_unknown))
 		{
 		  b1->error = node->errors[UDP_ERROR_PUNT];
 		  next1 = UDP_LOCAL_NEXT_PUNT;
 		}
 	      else if (is_ip4)
 		{
 		  icmp4_error_set_vnet_buffer (b1,
 					       ICMP4_destination_unreachable,
 					       ICMP4_destination_unreachable_port_unreachable,
 					       0);
 		  next1 = UDP_LOCAL_NEXT_ICMP;
 		  n_no_listener++;
 		}
 	      else
 		{
 		  icmp6_error_set_vnet_buffer (b1,
 					       ICMP6_destination_unreachable,
 					       ICMP6_destination_unreachable_port_unreachable,
 					       0);
 		  next1 = UDP_LOCAL_NEXT_ICMP;
 		  n_no_listener++;
 		}
 	    }
 	  else
 	    {
 	      b1->error = node->errors[UDP_ERROR_NONE];
 	      // advance to the payload
 	      vlib_buffer_advance (b1, sizeof (*h1));
 	    }

 	  if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 	    {
 	      udp_local_rx_trace_t *tr = vlib_add_trace (vm, node,
 							 b0, sizeof (*tr));
 	      if (b0->error != node->errors[UDP_ERROR_LENGTH_ERROR])
 		{
 		  tr->src_port = h0 ? h0->src_port : 0;
 		  tr->dst_port = h0 ? h0->dst_port : 0;
 		  tr->bound = (next0 != UDP_LOCAL_NEXT_ICMP);
 		}
 	    }
 	  if (PREDICT_FALSE (b1->flags & VLIB_BUFFER_IS_TRACED))
 	    {
 	      udp_local_rx_trace_t *tr = vlib_add_trace (vm, node,
 							 b1, sizeof (*tr));
 	      if (b1->error != node->errors[UDP_ERROR_LENGTH_ERROR])
 		{
 		  tr->src_port = h1 ? h1->src_port : 0;
 		  tr->dst_port = h1 ? h1->dst_port : 0;
 		  tr->bound = (next1 != UDP_LOCAL_NEXT_ICMP);
 		}
 	    }

 	  vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
 					   to_next, n_left_to_next,
 					   bi0, bi1, next0, next1);
 	}

       while (n_left_from > 0 && n_left_to_next > 0)
 	{
 	  u32 bi0;
 	  vlib_buffer_t *b0;
 	  udp_header_t *h0 = 0;
 	  u32 i0, next0;
 	  u32 advance0;

 	  bi0 = from[0];
 	  to_next[0] = bi0;
 	  from += 1;
 	  to_next += 1;
 	  n_left_from -= 1;
 	  n_left_to_next -= 1;

 	  b0 = vlib_get_buffer (vm, bi0);

 	  /* ip4/6_local hands us the ip header, not the udp header */
 	  if (is_ip4)
 	    advance0 = sizeof (ip4_header_t);
 	  else
 	    advance0 = sizeof (ip6_header_t);

 	  if (PREDICT_FALSE (b0->current_length < advance0 + sizeof (*h0)))
 	    {
 	      b0->error = node->errors[UDP_ERROR_LENGTH_ERROR];
 	      next0 = UDP_LOCAL_NEXT_DROP;
 	      goto trace_x1;
 	    }

 	  vlib_buffer_advance (b0, advance0);

 	  h0 = vlib_buffer_get_current (b0);

 	  if (PREDICT_TRUE (clib_net_to_host_u16 (h0->length) <=
 			    vlib_buffer_length_in_chain (vm, b0)))
 	    {
 	      i0 = sparse_vec_index (next_by_dst_port, h0->dst_port);
 	      next0 = vec_elt (next_by_dst_port, i0);

 	      if (PREDICT_FALSE ((i0 == SPARSE_VEC_INVALID_INDEX) ||
 				 next0 == UDP_NO_NODE_SET))
 		{
 		  // move the pointer back so icmp-error can find the
 		  // ip packet header
 		  vlib_buffer_advance (b0, -(word) advance0);

 		  if (PREDICT_FALSE (punt_unknown))
 		    {
 		      b0->error = node->errors[UDP_ERROR_PUNT];
 		      next0 = UDP_LOCAL_NEXT_PUNT;
 		    }
 		  else if (is_ip4)
 		    {
 		      icmp4_error_set_vnet_buffer (b0,
 						   ICMP4_destination_unreachable,
 						   ICMP4_destination_unreachable_port_unreachable,
 						   0);
 		      next0 = UDP_LOCAL_NEXT_ICMP;
 		      n_no_listener++;
 		    }
 		  else
 		    {
 		      icmp6_error_set_vnet_buffer (b0,
 						   ICMP6_destination_unreachable,
 						   ICMP6_destination_unreachable_port_unreachable,
 						   0);
 		      next0 = UDP_LOCAL_NEXT_ICMP;
 		      n_no_listener++;
 		    }
 		}
 	      else
 		{
 		  b0->error = node->errors[UDP_ERROR_NONE];
 		  // advance to the payload
 		  vlib_buffer_advance (b0, sizeof (*h0));
 		}
 	    }
 	  else
 	    {
 	      b0->error = node->errors[UDP_ERROR_LENGTH_ERROR];
 	      next0 = UDP_LOCAL_NEXT_DROP;
 	    }

 	trace_x1:
 	  if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 	    {
 	      udp_local_rx_trace_t *tr = vlib_add_trace (vm, node,
 							 b0, sizeof (*tr));
 	      if (b0->error != node->errors[UDP_ERROR_LENGTH_ERROR])
 		{
 		  tr->src_port = h0->src_port;
 		  tr->dst_port = h0->dst_port;
 		  tr->bound = (next0 != UDP_LOCAL_NEXT_ICMP);
 		}
 	    }

 	  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);
     }
   vlib_error_count (vm, node->node_index, UDP_ERROR_NO_LISTENER,
 		    n_no_listener);
   return from_frame->n_vectors;
 }

 static char *udp_error_strings[] = {
 #define udp_error(n,s) s,
 #include "udp_error.def"
 #undef udp_error
 };

 VLIB_NODE_FN (udp4_local_node) (vlib_main_t * vm,
 				vlib_node_runtime_t * node,
 				vlib_frame_t * from_frame)
 {
   return udp46_local_inline (vm, node, from_frame, 1 /* is_ip4 */ );
 }

 VLIB_NODE_FN (udp6_local_node) (vlib_main_t * vm,
 				vlib_node_runtime_t * node,
 				vlib_frame_t * from_frame)
 {
   return udp46_local_inline (vm, node, from_frame, 0 /* is_ip4 */ );
 }

 /* *INDENT-OFF* */
 VLIB_REGISTER_NODE (udp4_local_node) = {
   .name = "ip4-udp-lookup",
   /* Takes a vector of packets. */
   .vector_size = sizeof (u32),

   .n_errors = UDP_N_ERROR,
   .error_strings = udp_error_strings,

   .n_next_nodes = UDP_LOCAL_N_NEXT,
   .next_nodes = {
     [UDP_LOCAL_NEXT_PUNT]= "ip4-punt",
     [UDP_LOCAL_NEXT_DROP]= "ip4-drop",
     [UDP_LOCAL_NEXT_ICMP]= "ip4-icmp-error",
   },

   .format_buffer = format_udp_header,
   .format_trace = format_udp_rx_trace,
   .unformat_buffer = unformat_udp_header,
 };
 /* *INDENT-ON* */

 /* *INDENT-OFF* */
 VLIB_REGISTER_NODE (udp6_local_node) = {
   .name = "ip6-udp-lookup",
   /* Takes a vector of packets. */
   .vector_size = sizeof (u32),

   .n_errors = UDP_N_ERROR,
   .error_strings = udp_error_strings,

   .n_next_nodes = UDP_LOCAL_N_NEXT,
   .next_nodes = {
     [UDP_LOCAL_NEXT_PUNT]= "ip6-punt",
     [UDP_LOCAL_NEXT_DROP]= "ip6-drop",
     [UDP_LOCAL_NEXT_ICMP]= "ip6-icmp-error",
   },

   .format_buffer = format_udp_header,
   .format_trace = format_udp_rx_trace,
   .unformat_buffer = unformat_udp_header,
 };
 /* *INDENT-ON* */

 #ifndef CLIB_MARCH_VARIANT
 static void
 add_dst_port (udp_main_t * um,
 	      udp_dst_port_t dst_port, char *dst_port_name, u8 is_ip4)
 {
   udp_dst_port_info_t *pi;
   u32 i;

   vec_add2 (um->dst_port_infos[is_ip4], pi, 1);
   i = pi - um->dst_port_infos[is_ip4];

   pi->name = dst_port_name;
   pi->dst_port = dst_port;
   pi->next_index = pi->node_index = ~0;

   hash_set (um->dst_port_info_by_dst_port[is_ip4], dst_port, i);

   if (pi->name)
     hash_set_mem (um->dst_port_info_by_name[is_ip4], pi->name, i);
 }

 void
 udp_register_dst_port (vlib_main_t * vm,
 		       udp_dst_port_t dst_port, u32 node_index, u8 is_ip4)
 {
   udp_main_t *um = &udp_main;
   udp_dst_port_info_t *pi;
   u16 *n;

   {
     clib_error_t *error = vlib_call_init_function (vm, udp_local_init);
     if (error)
       clib_error_report (error);
   }

   pi = udp_get_dst_port_info (um, dst_port, is_ip4);
   if (!pi)
     {
       add_dst_port (um, dst_port, 0, is_ip4);
       pi = udp_get_dst_port_info (um, dst_port, is_ip4);
       ASSERT (pi);
     }

   pi->node_index = node_index;
   pi->next_index = vlib_node_add_next (vm,
 				       is_ip4 ? udp4_local_node.index
 				       : udp6_local_node.index, node_index);

   /* Setup udp protocol -> next index sparse vector mapping. */
   if (is_ip4)
     n = sparse_vec_validate (um->next_by_dst_port4,
 			     clib_host_to_net_u16 (dst_port));
   else
     n = sparse_vec_validate (um->next_by_dst_port6,
 			     clib_host_to_net_u16 (dst_port));

   n[0] = pi->next_index;
 }

 void
 udp_unregister_dst_port (vlib_main_t * vm, udp_dst_port_t dst_port, u8 is_ip4)
 {
   udp_main_t *um = &udp_main;
   udp_dst_port_info_t *pi;
   u16 *n;

   pi = udp_get_dst_port_info (um, dst_port, is_ip4);
   /* Not registered? Fagedaboudit */
   if (!pi)
     return;

   /* Kill the mapping. Don't bother killing the pi, it may be back. */
   if (is_ip4)
     n = sparse_vec_validate (um->next_by_dst_port4,
 			     clib_host_to_net_u16 (dst_port));
   else
     n = sparse_vec_validate (um->next_by_dst_port6,
 			     clib_host_to_net_u16 (dst_port));

   n[0] = UDP_NO_NODE_SET;
 }

 bool
 udp_is_valid_dst_port (udp_dst_port_t dst_port, u8 is_ip4)
 {
   udp_main_t *um = &udp_main;
   u16 *n;

   if (is_ip4)
     n = sparse_vec_validate (um->next_by_dst_port4,
 			     clib_host_to_net_u16 (dst_port));
   else
     n = sparse_vec_validate (um->next_by_dst_port6,
 			     clib_host_to_net_u16 (dst_port));

   return (n[0] != SPARSE_VEC_INVALID_INDEX && n[0] != UDP_NO_NODE_SET);
 }

 void
 udp_punt_unknown (vlib_main_t * vm, u8 is_ip4, u8 is_add)
 {
   udp_main_t *um = &udp_main;
   {
     clib_error_t *error = vlib_call_init_function (vm, udp_local_init);
     if (error)
       clib_error_report (error);
   }

   if (is_ip4)
     um->punt_unknown4 = is_add;
   else
     um->punt_unknown6 = is_add;
 }

 /* Parse a UDP header. */
 uword
 unformat_udp_header (unformat_input_t * input, va_list * args)
 {
   u8 **result = va_arg (*args, u8 **);
   udp_header_t *udp;
   __attribute__ ((unused)) int old_length;
   u16 src_port, dst_port;

   /* Allocate space for IP header. */
   {
     void *p;

     old_length = vec_len (*result);
     vec_add2 (*result, p, sizeof (ip4_header_t));
     udp = p;
   }

   clib_memset (udp, 0, sizeof (udp[0]));
   if (unformat (input, "src-port %d dst-port %d", &src_port, &dst_port))
     {
       udp->src_port = clib_host_to_net_u16 (src_port);
       udp->dst_port = clib_host_to_net_u16 (dst_port);
       return 1;
     }
   return 0;
 }

 static void
 udp_setup_node (vlib_main_t * vm, u32 node_index)
 {
   vlib_node_t *n = vlib_get_node (vm, node_index);
   pg_node_t *pn = pg_get_node (node_index);

   n->format_buffer = format_udp_header;
   n->unformat_buffer = unformat_udp_header;
   pn->unformat_edit = unformat_pg_udp_header;
 }

 clib_error_t *
 udp_local_init (vlib_main_t * vm)
 {
   udp_main_t *um = &udp_main;
   int i;

   {
     clib_error_t *error;
     error = vlib_call_init_function (vm, udp_init);
     if (error)
       clib_error_report (error);
   }


   for (i = 0; i < 2; i++)
     {
       um->dst_port_info_by_name[i] = hash_create_string (0, sizeof (uword));
       um->dst_port_info_by_dst_port[i] = hash_create (0, sizeof (uword));
     }

   udp_setup_node (vm, udp4_local_node.index);
   udp_setup_node (vm, udp6_local_node.index);

   um->punt_unknown4 = 0;
   um->punt_unknown6 = 0;

   um->next_by_dst_port4 = sparse_vec_new
     ( /* elt bytes */ sizeof (um->next_by_dst_port4[0]),
      /* bits in index */ BITS (((udp_header_t *) 0)->dst_port));

   um->next_by_dst_port6 = sparse_vec_new
     ( /* elt bytes */ sizeof (um->next_by_dst_port6[0]),
      /* bits in index */ BITS (((udp_header_t *) 0)->dst_port));

 #define _(n,s) add_dst_port (um, UDP_DST_PORT_##s, #s, 1 /* is_ip4 */);
   foreach_udp4_dst_port
 #undef _
 #define _(n,s) add_dst_port (um, UDP_DST_PORT_##s, #s, 0 /* is_ip4 */);
     foreach_udp6_dst_port
 #undef _
     ip4_register_protocol (IP_PROTOCOL_UDP, udp4_local_node.index);
   /* Note: ip6 differs from ip4, UDP is hotwired to ip6-udp-lookup */
   return 0;
 }

 VLIB_INIT_FUNCTION (udp_local_init);
 #endif /* CLIB_MARCH_VARIANT */

 /*
  * fd.io coding-style-patch-verification: ON
  *
  * Local Variables:
  * eval: (c-set-style "gnu")
  * End:
  */
	/*
	* node.c: udp packet processing
	*
	* Copyright (c) 2013-2019 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 <vlib/vlib.h>
	#include <vnet/pg/pg.h>
	#include <vnet/udp/udp.h>
	#include <vnet/udp/udp_packet.h>
	#include <vppinfra/sparse_vec.h>

	typedef enum
	{
	UDP_LOCAL_NEXT_PUNT,
	UDP_LOCAL_NEXT_DROP,
	UDP_LOCAL_NEXT_ICMP,
	UDP_LOCAL_N_NEXT
	} udp_local_next_t;

	typedef struct
	{
	u16 src_port;
	u16 dst_port;
	u8 bound;
	} udp_local_rx_trace_t;

	#define UDP_NO_NODE_SET ((u16) ~0)

	#ifndef CLIB_MARCH_VARIANT
	u8 *
	format_udp_rx_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 );
	udp_local_rx_trace_t t = va_arg (args, udp_local_rx_trace_t *);

	s = format (s, "UDP: src-port %d dst-port %d%s",
	clib_net_to_host_u16 (t->src_port),
	clib_net_to_host_u16 (t->dst_port),
	t->bound ? "" : " (no listener)");
	return s;
	}
	#endif /* CLIB_MARCH_VARIANT */

	always_inline uword
	udp46_local_inline (vlib_main_t * vm,
	vlib_node_runtime_t * node,
	vlib_frame_t * from_frame, int is_ip4)
	{
	udp_main_t *um = &udp_main;
	__attribute__ ((unused)) u32 n_left_from, next_index, from, to_next;
	word n_no_listener = 0;
	u8 punt_unknown = is_ip4 ? um->punt_unknown4 : um->punt_unknown6;
	u16 *next_by_dst_port = (is_ip4 ?
	um->next_by_dst_port4 : um->next_by_dst_port6);
	from = vlib_frame_vector_args (from_frame);
	n_left_from = 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 >= 4 && n_left_to_next >= 2)
	{
	u32 bi0, bi1;
	vlib_buffer_t b0, b1;
	udp_header_t h0 = 0, h1 = 0;
	u32 i0, i1, dst_port0, dst_port1;
	u32 advance0, advance1;
	u32 error0, next0, error1, next1;

	/* Prefetch next iteration. */
	{
	vlib_buffer_t p2, p3;

	p2 = vlib_get_buffer (vm, from[2]);
	p3 = vlib_get_buffer (vm, from[3]);

	vlib_prefetch_buffer_header (p2, LOAD);
	vlib_prefetch_buffer_header (p3, LOAD);

	CLIB_PREFETCH (p2->data, sizeof (h0[0]), LOAD);
	CLIB_PREFETCH (p3->data, sizeof (h1[0]), LOAD);
	}

	bi0 = from[0];
	bi1 = from[1];
	to_next[0] = bi0;
	to_next[1] = bi1;
	from += 2;
	to_next += 2;
	n_left_to_next -= 2;
	n_left_from -= 2;

	b0 = vlib_get_buffer (vm, bi0);
	b1 = vlib_get_buffer (vm, bi1);

	/* ip4/6_local hands us the ip header, not the udp header */
	if (is_ip4)
	{
	advance0 = sizeof (ip4_header_t);
	advance1 = sizeof (ip4_header_t);
	}
	else
	{
	advance0 = sizeof (ip6_header_t);
	advance1 = sizeof (ip6_header_t);
	}

	if (PREDICT_FALSE (b0->current_length < advance0 + sizeof (*h0)))
	{
	error0 = UDP_ERROR_LENGTH_ERROR;
	next0 = UDP_LOCAL_NEXT_DROP;
	}
	else
	{
	vlib_buffer_advance (b0, advance0);
	h0 = vlib_buffer_get_current (b0);
	error0 = UDP_ERROR_NONE;
	next0 = UDP_LOCAL_NEXT_PUNT;
	if (PREDICT_FALSE (clib_net_to_host_u16 (h0->length) >
	vlib_buffer_length_in_chain (vm, b0)))
	{
	error0 = UDP_ERROR_LENGTH_ERROR;
	next0 = UDP_LOCAL_NEXT_DROP;
	}
	}

	if (PREDICT_FALSE (b1->current_length < advance1 + sizeof (*h1)))
	{
	error1 = UDP_ERROR_LENGTH_ERROR;
	next1 = UDP_LOCAL_NEXT_DROP;
	}
	else
	{
	vlib_buffer_advance (b1, advance1);
	h1 = vlib_buffer_get_current (b1);
	error1 = UDP_ERROR_NONE;
	next1 = UDP_LOCAL_NEXT_PUNT;
	if (PREDICT_FALSE (clib_net_to_host_u16 (h1->length) >
	vlib_buffer_length_in_chain (vm, b1)))
	{
	error1 = UDP_ERROR_LENGTH_ERROR;
	next1 = UDP_LOCAL_NEXT_DROP;
	}
	}

	/* Index sparse array with network byte order. */
	dst_port0 = (error0 == 0) ? h0->dst_port : 0;
	dst_port1 = (error1 == 0) ? h1->dst_port : 0;
	sparse_vec_index2 (next_by_dst_port, dst_port0, dst_port1, &i0,
	&i1);
	next0 = (error0 == 0) ? vec_elt (next_by_dst_port, i0) : next0;
	next1 = (error1 == 0) ? vec_elt (next_by_dst_port, i1) : next1;

	if (PREDICT_FALSE (i0 == SPARSE_VEC_INVALID_INDEX \|\|
	next0 == UDP_NO_NODE_SET))
	{
	// move the pointer back so icmp-error can find the
	// ip packet header
	vlib_buffer_advance (b0, -(word) advance0);

	if (PREDICT_FALSE (punt_unknown))
	{
	b0->error = node->errors[UDP_ERROR_PUNT];
	next0 = UDP_LOCAL_NEXT_PUNT;
	}
	else if (is_ip4)
	{
	icmp4_error_set_vnet_buffer (b0,
	ICMP4_destination_unreachable,
	ICMP4_destination_unreachable_port_unreachable,
	0);
	next0 = UDP_LOCAL_NEXT_ICMP;
	n_no_listener++;
	}
	else
	{
	icmp6_error_set_vnet_buffer (b0,
	ICMP6_destination_unreachable,
	ICMP6_destination_unreachable_port_unreachable,
	0);
	next0 = UDP_LOCAL_NEXT_ICMP;
	n_no_listener++;
	}
	}
	else
	{
	b0->error = node->errors[UDP_ERROR_NONE];
	// advance to the payload
	vlib_buffer_advance (b0, sizeof (*h0));
	}

	if (PREDICT_FALSE (i1 == SPARSE_VEC_INVALID_INDEX \|\|
	next1 == UDP_NO_NODE_SET))
	{
	// move the pointer back so icmp-error can find the
	// ip packet header
	vlib_buffer_advance (b1, -(word) advance1);

	if (PREDICT_FALSE (punt_unknown))
	{
	b1->error = node->errors[UDP_ERROR_PUNT];
	next1 = UDP_LOCAL_NEXT_PUNT;
	}
	else if (is_ip4)
	{
	icmp4_error_set_vnet_buffer (b1,
	ICMP4_destination_unreachable,
	ICMP4_destination_unreachable_port_unreachable,
	0);
	next1 = UDP_LOCAL_NEXT_ICMP;
	n_no_listener++;
	}
	else
	{
	icmp6_error_set_vnet_buffer (b1,
	ICMP6_destination_unreachable,
	ICMP6_destination_unreachable_port_unreachable,
	0);
	next1 = UDP_LOCAL_NEXT_ICMP;
	n_no_listener++;
	}
	}
	else
	{
	b1->error = node->errors[UDP_ERROR_NONE];
	// advance to the payload
	vlib_buffer_advance (b1, sizeof (*h1));
	}

	if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
	{
	udp_local_rx_trace_t *tr = vlib_add_trace (vm, node,
	b0, sizeof (*tr));
	if (b0->error != node->errors[UDP_ERROR_LENGTH_ERROR])
	{
	tr->src_port = h0 ? h0->src_port : 0;
	tr->dst_port = h0 ? h0->dst_port : 0;
	tr->bound = (next0 != UDP_LOCAL_NEXT_ICMP);
	}
	}
	if (PREDICT_FALSE (b1->flags & VLIB_BUFFER_IS_TRACED))
	{
	udp_local_rx_trace_t *tr = vlib_add_trace (vm, node,
	b1, sizeof (*tr));
	if (b1->error != node->errors[UDP_ERROR_LENGTH_ERROR])
	{
	tr->src_port = h1 ? h1->src_port : 0;
	tr->dst_port = h1 ? h1->dst_port : 0;
	tr->bound = (next1 != UDP_LOCAL_NEXT_ICMP);
	}
	}

	vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
	to_next, n_left_to_next,
	bi0, bi1, next0, next1);
	}

	while (n_left_from > 0 && n_left_to_next > 0)
	{
	u32 bi0;
	vlib_buffer_t *b0;
	udp_header_t *h0 = 0;
	u32 i0, next0;
	u32 advance0;

	bi0 = from[0];
	to_next[0] = bi0;
	from += 1;
	to_next += 1;
	n_left_from -= 1;
	n_left_to_next -= 1;

	b0 = vlib_get_buffer (vm, bi0);

	/* ip4/6_local hands us the ip header, not the udp header */
	if (is_ip4)
	advance0 = sizeof (ip4_header_t);
	else
	advance0 = sizeof (ip6_header_t);

	if (PREDICT_FALSE (b0->current_length < advance0 + sizeof (*h0)))
	{
	b0->error = node->errors[UDP_ERROR_LENGTH_ERROR];
	next0 = UDP_LOCAL_NEXT_DROP;
	goto trace_x1;
	}

	vlib_buffer_advance (b0, advance0);

	h0 = vlib_buffer_get_current (b0);

	if (PREDICT_TRUE (clib_net_to_host_u16 (h0->length) <=
	vlib_buffer_length_in_chain (vm, b0)))
	{
	i0 = sparse_vec_index (next_by_dst_port, h0->dst_port);
	next0 = vec_elt (next_by_dst_port, i0);

	if (PREDICT_FALSE ((i0 == SPARSE_VEC_INVALID_INDEX) \|\|
	next0 == UDP_NO_NODE_SET))
	{
	// move the pointer back so icmp-error can find the
	// ip packet header
	vlib_buffer_advance (b0, -(word) advance0);

	if (PREDICT_FALSE (punt_unknown))
	{
	b0->error = node->errors[UDP_ERROR_PUNT];
	next0 = UDP_LOCAL_NEXT_PUNT;
	}
	else if (is_ip4)
	{
	icmp4_error_set_vnet_buffer (b0,
	ICMP4_destination_unreachable,
	ICMP4_destination_unreachable_port_unreachable,
	0);
	next0 = UDP_LOCAL_NEXT_ICMP;
	n_no_listener++;
	}
	else
	{
	icmp6_error_set_vnet_buffer (b0,
	ICMP6_destination_unreachable,
	ICMP6_destination_unreachable_port_unreachable,
	0);
	next0 = UDP_LOCAL_NEXT_ICMP;
	n_no_listener++;
	}
	}
	else
	{
	b0->error = node->errors[UDP_ERROR_NONE];
	// advance to the payload
	vlib_buffer_advance (b0, sizeof (*h0));
	}
	}
	else
	{
	b0->error = node->errors[UDP_ERROR_LENGTH_ERROR];
	next0 = UDP_LOCAL_NEXT_DROP;
	}

	trace_x1:
	if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
	{
	udp_local_rx_trace_t *tr = vlib_add_trace (vm, node,
	b0, sizeof (*tr));
	if (b0->error != node->errors[UDP_ERROR_LENGTH_ERROR])
	{
	tr->src_port = h0->src_port;
	tr->dst_port = h0->dst_port;
	tr->bound = (next0 != UDP_LOCAL_NEXT_ICMP);
	}
	}

	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);
	}
	vlib_error_count (vm, node->node_index, UDP_ERROR_NO_LISTENER,
	n_no_listener);
	return from_frame->n_vectors;
	}

	static char *udp_error_strings[] = {
	#define udp_error(n,s) s,
	#include "udp_error.def"
	#undef udp_error
	};

	VLIB_NODE_FN (udp4_local_node) (vlib_main_t * vm,
	vlib_node_runtime_t * node,
	vlib_frame_t * from_frame)
	{
	return udp46_local_inline (vm, node, from_frame, 1 /* is_ip4 */ );
	}

	VLIB_NODE_FN (udp6_local_node) (vlib_main_t * vm,
	vlib_node_runtime_t * node,
	vlib_frame_t * from_frame)
	{
	return udp46_local_inline (vm, node, from_frame, 0 /* is_ip4 */ );
	}

	/* INDENT-OFF */
	VLIB_REGISTER_NODE (udp4_local_node) = {
	.name = "ip4-udp-lookup",
	/* Takes a vector of packets. */
	.vector_size = sizeof (u32),

	.n_errors = UDP_N_ERROR,
	.error_strings = udp_error_strings,

	.n_next_nodes = UDP_LOCAL_N_NEXT,
	.next_nodes = {
	[UDP_LOCAL_NEXT_PUNT]= "ip4-punt",
	[UDP_LOCAL_NEXT_DROP]= "ip4-drop",
	[UDP_LOCAL_NEXT_ICMP]= "ip4-icmp-error",
	},

	.format_buffer = format_udp_header,
	.format_trace = format_udp_rx_trace,
	.unformat_buffer = unformat_udp_header,
	};
	/* INDENT-ON */

	/* INDENT-OFF */
	VLIB_REGISTER_NODE (udp6_local_node) = {
	.name = "ip6-udp-lookup",
	/* Takes a vector of packets. */
	.vector_size = sizeof (u32),

	.n_errors = UDP_N_ERROR,
	.error_strings = udp_error_strings,

	.n_next_nodes = UDP_LOCAL_N_NEXT,
	.next_nodes = {
	[UDP_LOCAL_NEXT_PUNT]= "ip6-punt",
	[UDP_LOCAL_NEXT_DROP]= "ip6-drop",
	[UDP_LOCAL_NEXT_ICMP]= "ip6-icmp-error",
	},

	.format_buffer = format_udp_header,
	.format_trace = format_udp_rx_trace,
	.unformat_buffer = unformat_udp_header,
	};
	/* INDENT-ON */

	#ifndef CLIB_MARCH_VARIANT
	static void
	add_dst_port (udp_main_t * um,
	udp_dst_port_t dst_port, char *dst_port_name, u8 is_ip4)
	{
	udp_dst_port_info_t *pi;
	u32 i;

	vec_add2 (um->dst_port_infos[is_ip4], pi, 1);
	i = pi - um->dst_port_infos[is_ip4];

	pi->name = dst_port_name;
	pi->dst_port = dst_port;
	pi->next_index = pi->node_index = ~0;

	hash_set (um->dst_port_info_by_dst_port[is_ip4], dst_port, i);

	if (pi->name)
	hash_set_mem (um->dst_port_info_by_name[is_ip4], pi->name, i);
	}

	void
	udp_register_dst_port (vlib_main_t * vm,
	udp_dst_port_t dst_port, u32 node_index, u8 is_ip4)
	{
	udp_main_t *um = &udp_main;
	udp_dst_port_info_t *pi;
	u16 *n;

	{
	clib_error_t *error = vlib_call_init_function (vm, udp_local_init);
	if (error)
	clib_error_report (error);
	}

	pi = udp_get_dst_port_info (um, dst_port, is_ip4);
	if (!pi)
	{
	add_dst_port (um, dst_port, 0, is_ip4);
	pi = udp_get_dst_port_info (um, dst_port, is_ip4);
	ASSERT (pi);
	}

	pi->node_index = node_index;
	pi->next_index = vlib_node_add_next (vm,
	is_ip4 ? udp4_local_node.index
	: udp6_local_node.index, node_index);

	/* Setup udp protocol -> next index sparse vector mapping. */
	if (is_ip4)
	n = sparse_vec_validate (um->next_by_dst_port4,
	clib_host_to_net_u16 (dst_port));
	else
	n = sparse_vec_validate (um->next_by_dst_port6,
	clib_host_to_net_u16 (dst_port));

	n[0] = pi->next_index;
	}

	void
	udp_unregister_dst_port (vlib_main_t * vm, udp_dst_port_t dst_port, u8 is_ip4)
	{
	udp_main_t *um = &udp_main;
	udp_dst_port_info_t *pi;
	u16 *n;

	pi = udp_get_dst_port_info (um, dst_port, is_ip4);
	/* Not registered? Fagedaboudit */
	if (!pi)
	return;

	/* Kill the mapping. Don't bother killing the pi, it may be back. */
	if (is_ip4)
	n = sparse_vec_validate (um->next_by_dst_port4,
	clib_host_to_net_u16 (dst_port));
	else
	n = sparse_vec_validate (um->next_by_dst_port6,
	clib_host_to_net_u16 (dst_port));

	n[0] = UDP_NO_NODE_SET;
	}

	bool
	udp_is_valid_dst_port (udp_dst_port_t dst_port, u8 is_ip4)
	{
	udp_main_t *um = &udp_main;
	u16 *n;

	if (is_ip4)
	n = sparse_vec_validate (um->next_by_dst_port4,
	clib_host_to_net_u16 (dst_port));
	else
	n = sparse_vec_validate (um->next_by_dst_port6,
	clib_host_to_net_u16 (dst_port));

	return (n[0] != SPARSE_VEC_INVALID_INDEX && n[0] != UDP_NO_NODE_SET);
	}

	void
	udp_punt_unknown (vlib_main_t * vm, u8 is_ip4, u8 is_add)
	{
	udp_main_t *um = &udp_main;
	{
	clib_error_t *error = vlib_call_init_function (vm, udp_local_init);
	if (error)
	clib_error_report (error);
	}

	if (is_ip4)
	um->punt_unknown4 = is_add;
	else
	um->punt_unknown6 = is_add;
	}

	/* Parse a UDP header. */
	uword
	unformat_udp_header (unformat_input_t * input, va_list * args)
	{
	u8 *result = va_arg (args, u8 **);
	udp_header_t *udp;
	__attribute__ ((unused)) int old_length;
	u16 src_port, dst_port;

	/* Allocate space for IP header. */
	{
	void *p;

	old_length = vec_len (*result);
	vec_add2 (*result, p, sizeof (ip4_header_t));
	udp = p;
	}

	clib_memset (udp, 0, sizeof (udp[0]));
	if (unformat (input, "src-port %d dst-port %d", &src_port, &dst_port))
	{
	udp->src_port = clib_host_to_net_u16 (src_port);
	udp->dst_port = clib_host_to_net_u16 (dst_port);
	return 1;
	}
	return 0;
	}

	static void
	udp_setup_node (vlib_main_t * vm, u32 node_index)
	{
	vlib_node_t *n = vlib_get_node (vm, node_index);
	pg_node_t *pn = pg_get_node (node_index);

	n->format_buffer = format_udp_header;
	n->unformat_buffer = unformat_udp_header;
	pn->unformat_edit = unformat_pg_udp_header;
	}

	clib_error_t *
	udp_local_init (vlib_main_t * vm)
	{
	udp_main_t *um = &udp_main;
	int i;

	{
	clib_error_t *error;
	error = vlib_call_init_function (vm, udp_init);
	if (error)
	clib_error_report (error);
	}


	for (i = 0; i < 2; i++)
	{
	um->dst_port_info_by_name[i] = hash_create_string (0, sizeof (uword));
	um->dst_port_info_by_dst_port[i] = hash_create (0, sizeof (uword));
	}

	udp_setup_node (vm, udp4_local_node.index);
	udp_setup_node (vm, udp6_local_node.index);

	um->punt_unknown4 = 0;
	um->punt_unknown6 = 0;

	um->next_by_dst_port4 = sparse_vec_new
	( /* elt bytes */ sizeof (um->next_by_dst_port4[0]),
	/* bits in index / BITS (((udp_header_t ) 0)->dst_port));

	um->next_by_dst_port6 = sparse_vec_new
	( /* elt bytes */ sizeof (um->next_by_dst_port6[0]),
	/* bits in index / BITS (((udp_header_t ) 0)->dst_port));

	#define _(n,s) add_dst_port (um, UDP_DST_PORT_##s, #s, 1 /* is_ip4 */);
	foreach_udp4_dst_port
	#undef _
	#define _(n,s) add_dst_port (um, UDP_DST_PORT_##s, #s, 0 /* is_ip4 */);
	foreach_udp6_dst_port
	#undef _
	ip4_register_protocol (IP_PROTOCOL_UDP, udp4_local_node.index);
	/* Note: ip6 differs from ip4, UDP is hotwired to ip6-udp-lookup */
	return 0;
	}

	VLIB_INIT_FUNCTION (udp_local_init);
	#endif /* CLIB_MARCH_VARIANT */

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