src/vnet/gre/node.c - fdio/vpp - Gitiles

 /*
  * node.c: gre packet processing
  *
  * Copyright (c) 2012 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/gre/gre.h>
 #include <vnet/mpls/mpls.h>
 #include <vppinfra/sparse_vec.h>

 #define foreach_gre_input_next			\
 _(PUNT, "error-punt")                           \
 _(DROP, "error-drop")                           \
 _(ETHERNET_INPUT, "ethernet-input")             \
 _(IP4_INPUT, "ip4-input")                       \
 _(IP6_INPUT, "ip6-input")			\
 _(MPLS_INPUT, "mpls-input")

 typedef enum
 {
 #define _(s,n) GRE_INPUT_NEXT_##s,
   foreach_gre_input_next
 #undef _
     GRE_INPUT_N_NEXT,
 } gre_input_next_t;

 typedef struct
 {
   u32 tunnel_id;
   u32 length;
   ip46_address_t src;
   ip46_address_t dst;
 } gre_rx_trace_t;

 extern u8 *format_gre_rx_trace (u8 * s, va_list * args);

 #ifndef CLIB_MARCH_VARIANT
 u8 *
 format_gre_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 *);
   gre_rx_trace_t *t = va_arg (*args, gre_rx_trace_t *);

   s = format (s, "GRE: tunnel %d len %d src %U dst %U",
 	      t->tunnel_id, clib_net_to_host_u16 (t->length),
 	      format_ip46_address, &t->src, IP46_TYPE_ANY,
 	      format_ip46_address, &t->dst, IP46_TYPE_ANY);
   return s;
 }
 #endif /* CLIB_MARCH_VARIANT */

 typedef struct
 {
   /* Sparse vector mapping gre protocol in network byte order
      to next index. */
   u16 *next_by_protocol;
 } gre_input_runtime_t;

 always_inline void
 gre_trace (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_buffer_t * b,
 	   u32 tun_sw_if_index, const ip6_header_t * ip6,
 	   const ip4_header_t * ip4, int is_ipv6)
 {
   gre_rx_trace_t *tr = vlib_add_trace (vm, node,
 				       b, sizeof (*tr));
   tr->tunnel_id = tun_sw_if_index;
   if (is_ipv6)
     {
       tr->length = ip6->payload_length;
       tr->src.ip6.as_u64[0] = ip6->src_address.as_u64[0];
       tr->src.ip6.as_u64[1] = ip6->src_address.as_u64[1];
       tr->dst.ip6.as_u64[0] = ip6->dst_address.as_u64[0];
       tr->dst.ip6.as_u64[1] = ip6->dst_address.as_u64[1];
     }
   else
     {
       tr->length = ip4->length;
       tr->src.as_u64[0] = tr->src.as_u64[1] = 0;
       tr->dst.as_u64[0] = tr->dst.as_u64[1] = 0;
       tr->src.ip4.as_u32 = ip4->src_address.as_u32;
       tr->dst.ip4.as_u32 = ip4->dst_address.as_u32;
     }
 }

 always_inline void
 gre_tunnel_get (const gre_main_t * gm, vlib_node_runtime_t * node,
 		vlib_buffer_t * b, u16 * next, const gre_tunnel_key_t * key,
 		gre_tunnel_key_t * cached_key, u32 * tun_sw_if_index,
 		u32 * cached_tun_sw_if_index, int is_ipv6)
 {
   const uword *p;
   p = is_ipv6 ? hash_get_mem (gm->tunnel_by_key6, &key->gtk_v6)
     : hash_get_mem (gm->tunnel_by_key4, &key->gtk_v4);
   if (PREDICT_FALSE (!p))
     {
       *next = GRE_INPUT_NEXT_DROP;
       b->error = node->errors[GRE_ERROR_NO_SUCH_TUNNEL];
       *tun_sw_if_index = ~0;
     }
   else
     {
       const gre_tunnel_t *tun;
       tun = pool_elt_at_index (gm->tunnels, *p);
       *cached_tun_sw_if_index = *tun_sw_if_index = tun->sw_if_index;
       if (is_ipv6)
 	cached_key->gtk_v6 = key->gtk_v6;
       else
 	cached_key->gtk_v4 = key->gtk_v4;
     }
 }

 always_inline uword
 gre_input (vlib_main_t * vm,
 	   vlib_node_runtime_t * node, vlib_frame_t * frame,
 	   const int is_ipv6)
 {
   gre_main_t *gm = &gre_main;
   u32 *from, n_left_from;
   vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b = bufs;
   u16 nexts[VLIB_FRAME_SIZE], *next = nexts;
   u16 cached_protocol = ~0;
   u32 cached_next_index = SPARSE_VEC_INVALID_INDEX;
   u32 cached_tun_sw_if_index = ~0;
   gre_tunnel_key_t cached_key;

   from = vlib_frame_vector_args (frame);
   n_left_from = frame->n_vectors;
   vlib_get_buffers (vm, from, bufs, n_left_from);

   if (is_ipv6)
     clib_memset (&cached_key.gtk_v6, 0xff, sizeof (cached_key.gtk_v6));
   else
     clib_memset (&cached_key.gtk_v4, 0xff, sizeof (cached_key.gtk_v4));

   while (n_left_from >= 2)
     {
       const ip6_header_t *ip6[2];
       const ip4_header_t *ip4[2];
       const gre_header_t *gre[2];
       u32 nidx[2];
       next_info_t ni[2];
       u8 type[2];
       u16 version[2];
       u32 len[2];
       gre_tunnel_key_t key[2];
       u8 matched[2];
       u32 tun_sw_if_index[2];

       if (PREDICT_TRUE (n_left_from >= 6))
 	{
 	  vlib_prefetch_buffer_data (b[2], LOAD);
 	  vlib_prefetch_buffer_data (b[3], LOAD);
 	  vlib_prefetch_buffer_header (b[4], STORE);
 	  vlib_prefetch_buffer_header (b[5], STORE);
 	}

       if (is_ipv6)
 	{
 	  /* ip6_local hands us the ip header, not the gre header */
 	  ip6[0] = vlib_buffer_get_current (b[0]);
 	  ip6[1] = vlib_buffer_get_current (b[1]);
 	  gre[0] = (void *) (ip6[0] + 1);
 	  gre[1] = (void *) (ip6[1] + 1);
 	  vlib_buffer_advance (b[0], sizeof (*ip6[0]) + sizeof (*gre[0]));
 	  vlib_buffer_advance (b[1], sizeof (*ip6[0]) + sizeof (*gre[0]));
 	}
       else
 	{
 	  /* ip4_local hands us the ip header, not the gre header */
 	  ip4[0] = vlib_buffer_get_current (b[0]);
 	  ip4[1] = vlib_buffer_get_current (b[1]);
 	  gre[0] = (void *) (ip4[0] + 1);
 	  gre[1] = (void *) (ip4[1] + 1);
 	  vlib_buffer_advance (b[0], sizeof (*ip4[0]) + sizeof (*gre[0]));
 	  vlib_buffer_advance (b[1], sizeof (*ip4[0]) + sizeof (*gre[0]));
 	}

       if (PREDICT_TRUE (cached_protocol == gre[0]->protocol))
 	{
 	  nidx[0] = cached_next_index;
 	}
       else
 	{
 	  cached_next_index = nidx[0] =
 	    sparse_vec_index (gm->next_by_protocol, gre[0]->protocol);
 	  cached_protocol = gre[0]->protocol;
 	}
       if (PREDICT_TRUE (cached_protocol == gre[1]->protocol))
 	{
 	  nidx[1] = cached_next_index;
 	}
       else
 	{
 	  cached_next_index = nidx[1] =
 	    sparse_vec_index (gm->next_by_protocol, gre[1]->protocol);
 	  cached_protocol = gre[1]->protocol;
 	}

       ni[0] = vec_elt (gm->next_by_protocol, nidx[0]);
       ni[1] = vec_elt (gm->next_by_protocol, nidx[1]);
       next[0] = ni[0].next_index;
       next[1] = ni[1].next_index;
       type[0] = ni[0].tunnel_type;
       type[1] = ni[1].tunnel_type;

       b[0]->error = nidx[0] == SPARSE_VEC_INVALID_INDEX
 	? node->errors[GRE_ERROR_UNKNOWN_PROTOCOL]
 	: node->errors[GRE_ERROR_NONE];
       b[1]->error = nidx[1] == SPARSE_VEC_INVALID_INDEX
 	? node->errors[GRE_ERROR_UNKNOWN_PROTOCOL]
 	: node->errors[GRE_ERROR_NONE];

       version[0] = clib_net_to_host_u16 (gre[0]->flags_and_version);
       version[1] = clib_net_to_host_u16 (gre[1]->flags_and_version);
       version[0] &= GRE_VERSION_MASK;
       version[1] &= GRE_VERSION_MASK;

       b[0]->error = version[0]
 	? node->errors[GRE_ERROR_UNSUPPORTED_VERSION] : b[0]->error;
       next[0] = version[0] ? GRE_INPUT_NEXT_DROP : next[0];
       b[1]->error = version[1]
 	? node->errors[GRE_ERROR_UNSUPPORTED_VERSION] : b[1]->error;
       next[1] = version[1] ? GRE_INPUT_NEXT_DROP : next[1];

       len[0] = vlib_buffer_length_in_chain (vm, b[0]);
       len[1] = vlib_buffer_length_in_chain (vm, b[1]);

       /* always search for P2P types in the DP */
       if (is_ipv6)
 	{
 	  gre_mk_key6 (&ip6[0]->dst_address,
 		       &ip6[0]->src_address,
 		       vnet_buffer (b[0])->ip.fib_index,
 		       type[0], TUNNEL_MODE_P2P, 0, &key[0].gtk_v6);
 	  gre_mk_key6 (&ip6[1]->dst_address,
 		       &ip6[1]->src_address,
 		       vnet_buffer (b[1])->ip.fib_index,
 		       type[1], TUNNEL_MODE_P2P, 0, &key[1].gtk_v6);
 	  matched[0] = gre_match_key6 (&cached_key.gtk_v6, &key[0].gtk_v6);
 	  matched[1] = gre_match_key6 (&cached_key.gtk_v6, &key[1].gtk_v6);
 	}
       else
 	{
 	  gre_mk_key4 (ip4[0]->dst_address,
 		       ip4[0]->src_address,
 		       vnet_buffer (b[0])->ip.fib_index,
 		       type[0], TUNNEL_MODE_P2P, 0, &key[0].gtk_v4);
 	  gre_mk_key4 (ip4[1]->dst_address,
 		       ip4[1]->src_address,
 		       vnet_buffer (b[1])->ip.fib_index,
 		       type[1], TUNNEL_MODE_P2P, 0, &key[1].gtk_v4);
 	  matched[0] = gre_match_key4 (&cached_key.gtk_v4, &key[0].gtk_v4);
 	  matched[1] = gre_match_key4 (&cached_key.gtk_v4, &key[1].gtk_v4);
 	}

       tun_sw_if_index[0] = cached_tun_sw_if_index;
       tun_sw_if_index[1] = cached_tun_sw_if_index;
       if (PREDICT_FALSE (!matched[0]))
 	gre_tunnel_get (gm, node, b[0], &next[0], &key[0], &cached_key,
 			&tun_sw_if_index[0], &cached_tun_sw_if_index,
 			is_ipv6);
       if (PREDICT_FALSE (!matched[1]))
 	gre_tunnel_get (gm, node, b[1], &next[1], &key[1], &cached_key,
 			&tun_sw_if_index[1], &cached_tun_sw_if_index,
 			is_ipv6);

       if (PREDICT_TRUE (next[0] > GRE_INPUT_NEXT_DROP))
 	{
 	  vlib_increment_combined_counter (&gm->vnet_main->
 					   interface_main.combined_sw_if_counters
 					   [VNET_INTERFACE_COUNTER_RX],
 					   vm->thread_index,
 					   tun_sw_if_index[0],
 					   1 /* packets */ ,
 					   len[0] /* bytes */ );
 	  vnet_buffer (b[0])->sw_if_index[VLIB_RX] = tun_sw_if_index[0];
 	}
       if (PREDICT_TRUE (next[1] > GRE_INPUT_NEXT_DROP))
 	{
 	  vlib_increment_combined_counter (&gm->vnet_main->
 					   interface_main.combined_sw_if_counters
 					   [VNET_INTERFACE_COUNTER_RX],
 					   vm->thread_index,
 					   tun_sw_if_index[1],
 					   1 /* packets */ ,
 					   len[1] /* bytes */ );
 	  vnet_buffer (b[1])->sw_if_index[VLIB_RX] = tun_sw_if_index[1];
 	}

       if (PREDICT_FALSE (b[0]->flags & VLIB_BUFFER_IS_TRACED))
 	gre_trace (vm, node, b[0], tun_sw_if_index[0], ip6[0], ip4[0],
 		   is_ipv6);
       if (PREDICT_FALSE (b[1]->flags & VLIB_BUFFER_IS_TRACED))
 	gre_trace (vm, node, b[1], tun_sw_if_index[1], ip6[1], ip4[1],
 		   is_ipv6);

       b += 2;
       next += 2;
       n_left_from -= 2;
     }

   while (n_left_from >= 1)
     {
       const ip6_header_t *ip6[1];
       const ip4_header_t *ip4[1];
       const gre_header_t *gre[1];
       u32 nidx[1];
       next_info_t ni[1];
       u8 type[1];
       u16 version[1];
       u32 len[1];
       gre_tunnel_key_t key[1];
       u8 matched[1];
       u32 tun_sw_if_index[1];

       if (PREDICT_TRUE (n_left_from >= 3))
 	{
 	  vlib_prefetch_buffer_data (b[1], LOAD);
 	  vlib_prefetch_buffer_header (b[2], STORE);
 	}

       if (is_ipv6)
 	{
 	  /* ip6_local hands us the ip header, not the gre header */
 	  ip6[0] = vlib_buffer_get_current (b[0]);
 	  gre[0] = (void *) (ip6[0] + 1);
 	  vlib_buffer_advance (b[0], sizeof (*ip6[0]) + sizeof (*gre[0]));
 	}
       else
 	{
 	  /* ip4_local hands us the ip header, not the gre header */
 	  ip4[0] = vlib_buffer_get_current (b[0]);
 	  gre[0] = (void *) (ip4[0] + 1);
 	  vlib_buffer_advance (b[0], sizeof (*ip4[0]) + sizeof (*gre[0]));
 	}

       if (PREDICT_TRUE (cached_protocol == gre[0]->protocol))
 	{
 	  nidx[0] = cached_next_index;
 	}
       else
 	{
 	  cached_next_index = nidx[0] =
 	    sparse_vec_index (gm->next_by_protocol, gre[0]->protocol);
 	  cached_protocol = gre[0]->protocol;
 	}

       ni[0] = vec_elt (gm->next_by_protocol, nidx[0]);
       next[0] = ni[0].next_index;
       type[0] = ni[0].tunnel_type;

       b[0]->error = nidx[0] == SPARSE_VEC_INVALID_INDEX
 	? node->errors[GRE_ERROR_UNKNOWN_PROTOCOL]
 	: node->errors[GRE_ERROR_NONE];

       version[0] = clib_net_to_host_u16 (gre[0]->flags_and_version);
       version[0] &= GRE_VERSION_MASK;

       b[0]->error = version[0]
 	? node->errors[GRE_ERROR_UNSUPPORTED_VERSION] : b[0]->error;
       next[0] = version[0] ? GRE_INPUT_NEXT_DROP : next[0];

       len[0] = vlib_buffer_length_in_chain (vm, b[0]);

       if (is_ipv6)
 	{
 	  gre_mk_key6 (&ip6[0]->dst_address,
 		       &ip6[0]->src_address,
 		       vnet_buffer (b[0])->ip.fib_index,
 		       type[0], TUNNEL_MODE_P2P, 0, &key[0].gtk_v6);
 	  matched[0] = gre_match_key6 (&cached_key.gtk_v6, &key[0].gtk_v6);
 	}
       else
 	{
 	  gre_mk_key4 (ip4[0]->dst_address,
 		       ip4[0]->src_address,
 		       vnet_buffer (b[0])->ip.fib_index,
 		       type[0], TUNNEL_MODE_P2P, 0, &key[0].gtk_v4);
 	  matched[0] = gre_match_key4 (&cached_key.gtk_v4, &key[0].gtk_v4);
 	}

       tun_sw_if_index[0] = cached_tun_sw_if_index;
       if (PREDICT_FALSE (!matched[0]))
 	gre_tunnel_get (gm, node, b[0], &next[0], &key[0], &cached_key,
 			&tun_sw_if_index[0], &cached_tun_sw_if_index,
 			is_ipv6);

       if (PREDICT_TRUE (next[0] > GRE_INPUT_NEXT_DROP))
 	{
 	  vlib_increment_combined_counter (&gm->vnet_main->
 					   interface_main.combined_sw_if_counters
 					   [VNET_INTERFACE_COUNTER_RX],
 					   vm->thread_index,
 					   tun_sw_if_index[0],
 					   1 /* packets */ ,
 					   len[0] /* bytes */ );
 	  vnet_buffer (b[0])->sw_if_index[VLIB_RX] = tun_sw_if_index[0];
 	}

       if (PREDICT_FALSE (b[0]->flags & VLIB_BUFFER_IS_TRACED))
 	gre_trace (vm, node, b[0], tun_sw_if_index[0], ip6[0], ip4[0],
 		   is_ipv6);

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

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

   vlib_node_increment_counter (vm,
 			       is_ipv6 ? gre6_input_node.index :
 			       gre4_input_node.index, GRE_ERROR_PKTS_DECAP,
 			       n_left_from);

   return frame->n_vectors;
 }

 VLIB_NODE_FN (gre4_input_node) (vlib_main_t * vm,
 				vlib_node_runtime_t * node,
 				vlib_frame_t * from_frame)
 {
   return gre_input (vm, node, from_frame, /* is_ip6 */ 0);
 }

 VLIB_NODE_FN (gre6_input_node) (vlib_main_t * vm,
 				vlib_node_runtime_t * node,
 				vlib_frame_t * from_frame)
 {
   return gre_input (vm, node, from_frame, /* is_ip6 */ 1);
 }

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

 /* *INDENT-OFF* */
 VLIB_REGISTER_NODE (gre4_input_node) = {
   .name = "gre4-input",
   /* Takes a vector of packets. */
   .vector_size = sizeof (u32),

   .n_errors = GRE_N_ERROR,
   .error_strings = gre_error_strings,

   .n_next_nodes = GRE_INPUT_N_NEXT,
   .next_nodes = {
 #define _(s,n) [GRE_INPUT_NEXT_##s] = n,
     foreach_gre_input_next
 #undef _
   },

   .format_buffer = format_gre_header_with_length,
   .format_trace = format_gre_rx_trace,
   .unformat_buffer = unformat_gre_header,
 };

 VLIB_REGISTER_NODE (gre6_input_node) = {
   .name = "gre6-input",
   /* Takes a vector of packets. */
   .vector_size = sizeof (u32),

   .runtime_data_bytes = sizeof (gre_input_runtime_t),

   .n_errors = GRE_N_ERROR,
   .error_strings = gre_error_strings,

   .n_next_nodes = GRE_INPUT_N_NEXT,
   .next_nodes = {
 #define _(s,n) [GRE_INPUT_NEXT_##s] = n,
     foreach_gre_input_next
 #undef _
   },

   .format_buffer = format_gre_header_with_length,
   .format_trace = format_gre_rx_trace,
   .unformat_buffer = unformat_gre_header,
 };
 /* *INDENT-ON* */

 #ifndef CLIB_MARCH_VARIANT
 void
 gre_register_input_protocol (vlib_main_t * vm,
 			     gre_protocol_t protocol, u32 node_index,
 			     gre_tunnel_type_t tunnel_type)
 {
   gre_main_t *em = &gre_main;
   gre_protocol_info_t *pi;
   next_info_t *n;
   u32 i;

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

   pi = gre_get_protocol_info (em, protocol);
   pi->node_index = node_index;
   pi->tunnel_type = tunnel_type;
   pi->next_index = vlib_node_add_next (vm, gre4_input_node.index, node_index);
   i = vlib_node_add_next (vm, gre6_input_node.index, node_index);
   ASSERT (i == pi->next_index);

   /* Setup gre protocol -> next index sparse vector mapping. */
   n = sparse_vec_validate (em->next_by_protocol,
 			   clib_host_to_net_u16 (protocol));
   n->next_index = pi->next_index;
   n->tunnel_type = tunnel_type;
 }

 static void
 gre_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_gre_header_with_length;
   n->unformat_buffer = unformat_gre_header;
   pn->unformat_edit = unformat_pg_gre_header;
 }

 static clib_error_t *
 gre_input_init (vlib_main_t * vm)
 {
   gre_main_t *gm = &gre_main;
   vlib_node_t *ethernet_input, *ip4_input, *ip6_input, *mpls_unicast_input;

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

   gre_setup_node (vm, gre4_input_node.index);
   gre_setup_node (vm, gre6_input_node.index);

   gm->next_by_protocol = sparse_vec_new
     ( /* elt bytes */ sizeof (gm->next_by_protocol[0]),
      /* bits in index */ BITS (((gre_header_t *) 0)->protocol));

   /* These could be moved to the supported protocol input node defn's */
   ethernet_input = vlib_get_node_by_name (vm, (u8 *) "ethernet-input");
   ASSERT (ethernet_input);
   ip4_input = vlib_get_node_by_name (vm, (u8 *) "ip4-input");
   ASSERT (ip4_input);
   ip6_input = vlib_get_node_by_name (vm, (u8 *) "ip6-input");
   ASSERT (ip6_input);
   mpls_unicast_input = vlib_get_node_by_name (vm, (u8 *) "mpls-input");
   ASSERT (mpls_unicast_input);

   gre_register_input_protocol (vm, GRE_PROTOCOL_teb,
 			       ethernet_input->index, GRE_TUNNEL_TYPE_TEB);

   gre_register_input_protocol (vm, GRE_PROTOCOL_ip4,
 			       ip4_input->index, GRE_TUNNEL_TYPE_L3);

   gre_register_input_protocol (vm, GRE_PROTOCOL_ip6,
 			       ip6_input->index, GRE_TUNNEL_TYPE_L3);

   gre_register_input_protocol (vm, GRE_PROTOCOL_mpls_unicast,
 			       mpls_unicast_input->index, GRE_TUNNEL_TYPE_L3);

   return 0;
 }

 VLIB_INIT_FUNCTION (gre_input_init);

 #endif /* CLIB_MARCH_VARIANT */
 /*
  * fd.io coding-style-patch-verification: ON
  *
  * Local Variables:
  * eval: (c-set-style "gnu")
  * End:
  */
	/*
	* node.c: gre packet processing
	*
	* Copyright (c) 2012 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/gre/gre.h>
	#include <vnet/mpls/mpls.h>
	#include <vppinfra/sparse_vec.h>

	#define foreach_gre_input_next \
	_(PUNT, "error-punt") \
	_(DROP, "error-drop") \
	_(ETHERNET_INPUT, "ethernet-input") \
	_(IP4_INPUT, "ip4-input") \
	_(IP6_INPUT, "ip6-input") \
	_(MPLS_INPUT, "mpls-input")

	typedef enum
	{
	#define _(s,n) GRE_INPUT_NEXT_##s,
	foreach_gre_input_next
	#undef _
	GRE_INPUT_N_NEXT,
	} gre_input_next_t;

	typedef struct
	{
	u32 tunnel_id;
	u32 length;
	ip46_address_t src;
	ip46_address_t dst;
	} gre_rx_trace_t;

	extern u8 format_gre_rx_trace (u8 s, va_list * args);

	#ifndef CLIB_MARCH_VARIANT
	u8 *
	format_gre_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 );
	gre_rx_trace_t t = va_arg (args, gre_rx_trace_t *);

	s = format (s, "GRE: tunnel %d len %d src %U dst %U",
	t->tunnel_id, clib_net_to_host_u16 (t->length),
	format_ip46_address, &t->src, IP46_TYPE_ANY,
	format_ip46_address, &t->dst, IP46_TYPE_ANY);
	return s;
	}
	#endif /* CLIB_MARCH_VARIANT */

	typedef struct
	{
	/* Sparse vector mapping gre protocol in network byte order
	to next index. */
	u16 *next_by_protocol;
	} gre_input_runtime_t;

	always_inline void
	gre_trace (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_buffer_t * b,
	u32 tun_sw_if_index, const ip6_header_t * ip6,
	const ip4_header_t * ip4, int is_ipv6)
	{
	gre_rx_trace_t *tr = vlib_add_trace (vm, node,
	b, sizeof (*tr));
	tr->tunnel_id = tun_sw_if_index;
	if (is_ipv6)
	{
	tr->length = ip6->payload_length;
	tr->src.ip6.as_u64[0] = ip6->src_address.as_u64[0];
	tr->src.ip6.as_u64[1] = ip6->src_address.as_u64[1];
	tr->dst.ip6.as_u64[0] = ip6->dst_address.as_u64[0];
	tr->dst.ip6.as_u64[1] = ip6->dst_address.as_u64[1];
	}
	else
	{
	tr->length = ip4->length;
	tr->src.as_u64[0] = tr->src.as_u64[1] = 0;
	tr->dst.as_u64[0] = tr->dst.as_u64[1] = 0;
	tr->src.ip4.as_u32 = ip4->src_address.as_u32;
	tr->dst.ip4.as_u32 = ip4->dst_address.as_u32;
	}
	}

	always_inline void
	gre_tunnel_get (const gre_main_t * gm, vlib_node_runtime_t * node,
	vlib_buffer_t * b, u16 * next, const gre_tunnel_key_t * key,
	gre_tunnel_key_t * cached_key, u32 * tun_sw_if_index,
	u32 * cached_tun_sw_if_index, int is_ipv6)
	{
	const uword *p;
	p = is_ipv6 ? hash_get_mem (gm->tunnel_by_key6, &key->gtk_v6)
	: hash_get_mem (gm->tunnel_by_key4, &key->gtk_v4);
	if (PREDICT_FALSE (!p))
	{
	*next = GRE_INPUT_NEXT_DROP;
	b->error = node->errors[GRE_ERROR_NO_SUCH_TUNNEL];
	*tun_sw_if_index = ~0;
	}
	else
	{
	const gre_tunnel_t *tun;
	tun = pool_elt_at_index (gm->tunnels, *p);
	cached_tun_sw_if_index = tun_sw_if_index = tun->sw_if_index;
	if (is_ipv6)
	cached_key->gtk_v6 = key->gtk_v6;
	else
	cached_key->gtk_v4 = key->gtk_v4;
	}
	}

	always_inline uword
	gre_input (vlib_main_t * vm,
	vlib_node_runtime_t * node, vlib_frame_t * frame,
	const int is_ipv6)
	{
	gre_main_t *gm = &gre_main;
	u32 *from, n_left_from;
	vlib_buffer_t bufs[VLIB_FRAME_SIZE], *b = bufs;
	u16 nexts[VLIB_FRAME_SIZE], *next = nexts;
	u16 cached_protocol = ~0;
	u32 cached_next_index = SPARSE_VEC_INVALID_INDEX;
	u32 cached_tun_sw_if_index = ~0;
	gre_tunnel_key_t cached_key;

	from = vlib_frame_vector_args (frame);
	n_left_from = frame->n_vectors;
	vlib_get_buffers (vm, from, bufs, n_left_from);

	if (is_ipv6)
	clib_memset (&cached_key.gtk_v6, 0xff, sizeof (cached_key.gtk_v6));
	else
	clib_memset (&cached_key.gtk_v4, 0xff, sizeof (cached_key.gtk_v4));

	while (n_left_from >= 2)
	{
	const ip6_header_t *ip6[2];
	const ip4_header_t *ip4[2];
	const gre_header_t *gre[2];
	u32 nidx[2];
	next_info_t ni[2];
	u8 type[2];
	u16 version[2];
	u32 len[2];
	gre_tunnel_key_t key[2];
	u8 matched[2];
	u32 tun_sw_if_index[2];

	if (PREDICT_TRUE (n_left_from >= 6))
	{
	vlib_prefetch_buffer_data (b[2], LOAD);
	vlib_prefetch_buffer_data (b[3], LOAD);
	vlib_prefetch_buffer_header (b[4], STORE);
	vlib_prefetch_buffer_header (b[5], STORE);
	}

	if (is_ipv6)
	{
	/* ip6_local hands us the ip header, not the gre header */
	ip6[0] = vlib_buffer_get_current (b[0]);
	ip6[1] = vlib_buffer_get_current (b[1]);
	gre[0] = (void *) (ip6[0] + 1);
	gre[1] = (void *) (ip6[1] + 1);
	vlib_buffer_advance (b[0], sizeof (ip6[0]) + sizeof (gre[0]));
	vlib_buffer_advance (b[1], sizeof (ip6[0]) + sizeof (gre[0]));
	}
	else
	{
	/* ip4_local hands us the ip header, not the gre header */
	ip4[0] = vlib_buffer_get_current (b[0]);
	ip4[1] = vlib_buffer_get_current (b[1]);
	gre[0] = (void *) (ip4[0] + 1);
	gre[1] = (void *) (ip4[1] + 1);
	vlib_buffer_advance (b[0], sizeof (ip4[0]) + sizeof (gre[0]));
	vlib_buffer_advance (b[1], sizeof (ip4[0]) + sizeof (gre[0]));
	}

	if (PREDICT_TRUE (cached_protocol == gre[0]->protocol))
	{
	nidx[0] = cached_next_index;
	}
	else
	{
	cached_next_index = nidx[0] =
	sparse_vec_index (gm->next_by_protocol, gre[0]->protocol);
	cached_protocol = gre[0]->protocol;
	}
	if (PREDICT_TRUE (cached_protocol == gre[1]->protocol))
	{
	nidx[1] = cached_next_index;
	}
	else
	{
	cached_next_index = nidx[1] =
	sparse_vec_index (gm->next_by_protocol, gre[1]->protocol);
	cached_protocol = gre[1]->protocol;
	}

	ni[0] = vec_elt (gm->next_by_protocol, nidx[0]);
	ni[1] = vec_elt (gm->next_by_protocol, nidx[1]);
	next[0] = ni[0].next_index;
	next[1] = ni[1].next_index;
	type[0] = ni[0].tunnel_type;
	type[1] = ni[1].tunnel_type;

	b[0]->error = nidx[0] == SPARSE_VEC_INVALID_INDEX
	? node->errors[GRE_ERROR_UNKNOWN_PROTOCOL]
	: node->errors[GRE_ERROR_NONE];
	b[1]->error = nidx[1] == SPARSE_VEC_INVALID_INDEX
	? node->errors[GRE_ERROR_UNKNOWN_PROTOCOL]
	: node->errors[GRE_ERROR_NONE];

	version[0] = clib_net_to_host_u16 (gre[0]->flags_and_version);
	version[1] = clib_net_to_host_u16 (gre[1]->flags_and_version);
	version[0] &= GRE_VERSION_MASK;
	version[1] &= GRE_VERSION_MASK;

	b[0]->error = version[0]
	? node->errors[GRE_ERROR_UNSUPPORTED_VERSION] : b[0]->error;
	next[0] = version[0] ? GRE_INPUT_NEXT_DROP : next[0];
	b[1]->error = version[1]
	? node->errors[GRE_ERROR_UNSUPPORTED_VERSION] : b[1]->error;
	next[1] = version[1] ? GRE_INPUT_NEXT_DROP : next[1];

	len[0] = vlib_buffer_length_in_chain (vm, b[0]);
	len[1] = vlib_buffer_length_in_chain (vm, b[1]);

	/* always search for P2P types in the DP */
	if (is_ipv6)
	{
	gre_mk_key6 (&ip6[0]->dst_address,
	&ip6[0]->src_address,
	vnet_buffer (b[0])->ip.fib_index,
	type[0], TUNNEL_MODE_P2P, 0, &key[0].gtk_v6);
	gre_mk_key6 (&ip6[1]->dst_address,
	&ip6[1]->src_address,
	vnet_buffer (b[1])->ip.fib_index,
	type[1], TUNNEL_MODE_P2P, 0, &key[1].gtk_v6);
	matched[0] = gre_match_key6 (&cached_key.gtk_v6, &key[0].gtk_v6);
	matched[1] = gre_match_key6 (&cached_key.gtk_v6, &key[1].gtk_v6);
	}
	else
	{
	gre_mk_key4 (ip4[0]->dst_address,
	ip4[0]->src_address,
	vnet_buffer (b[0])->ip.fib_index,
	type[0], TUNNEL_MODE_P2P, 0, &key[0].gtk_v4);
	gre_mk_key4 (ip4[1]->dst_address,
	ip4[1]->src_address,
	vnet_buffer (b[1])->ip.fib_index,
	type[1], TUNNEL_MODE_P2P, 0, &key[1].gtk_v4);
	matched[0] = gre_match_key4 (&cached_key.gtk_v4, &key[0].gtk_v4);
	matched[1] = gre_match_key4 (&cached_key.gtk_v4, &key[1].gtk_v4);
	}

	tun_sw_if_index[0] = cached_tun_sw_if_index;
	tun_sw_if_index[1] = cached_tun_sw_if_index;
	if (PREDICT_FALSE (!matched[0]))
	gre_tunnel_get (gm, node, b[0], &next[0], &key[0], &cached_key,
	&tun_sw_if_index[0], &cached_tun_sw_if_index,
	is_ipv6);
	if (PREDICT_FALSE (!matched[1]))
	gre_tunnel_get (gm, node, b[1], &next[1], &key[1], &cached_key,
	&tun_sw_if_index[1], &cached_tun_sw_if_index,
	is_ipv6);

	if (PREDICT_TRUE (next[0] > GRE_INPUT_NEXT_DROP))
	{
	vlib_increment_combined_counter (&gm->vnet_main->
	interface_main.combined_sw_if_counters
	[VNET_INTERFACE_COUNTER_RX],
	vm->thread_index,
	tun_sw_if_index[0],
	1 /* packets */ ,
	len[0] /* bytes */ );
	vnet_buffer (b[0])->sw_if_index[VLIB_RX] = tun_sw_if_index[0];
	}
	if (PREDICT_TRUE (next[1] > GRE_INPUT_NEXT_DROP))
	{
	vlib_increment_combined_counter (&gm->vnet_main->
	interface_main.combined_sw_if_counters
	[VNET_INTERFACE_COUNTER_RX],
	vm->thread_index,
	tun_sw_if_index[1],
	1 /* packets */ ,
	len[1] /* bytes */ );
	vnet_buffer (b[1])->sw_if_index[VLIB_RX] = tun_sw_if_index[1];
	}

	if (PREDICT_FALSE (b[0]->flags & VLIB_BUFFER_IS_TRACED))
	gre_trace (vm, node, b[0], tun_sw_if_index[0], ip6[0], ip4[0],
	is_ipv6);
	if (PREDICT_FALSE (b[1]->flags & VLIB_BUFFER_IS_TRACED))
	gre_trace (vm, node, b[1], tun_sw_if_index[1], ip6[1], ip4[1],
	is_ipv6);

	b += 2;
	next += 2;
	n_left_from -= 2;
	}

	while (n_left_from >= 1)
	{
	const ip6_header_t *ip6[1];
	const ip4_header_t *ip4[1];
	const gre_header_t *gre[1];
	u32 nidx[1];
	next_info_t ni[1];
	u8 type[1];
	u16 version[1];
	u32 len[1];
	gre_tunnel_key_t key[1];
	u8 matched[1];
	u32 tun_sw_if_index[1];

	if (PREDICT_TRUE (n_left_from >= 3))
	{
	vlib_prefetch_buffer_data (b[1], LOAD);
	vlib_prefetch_buffer_header (b[2], STORE);
	}

	if (is_ipv6)
	{
	/* ip6_local hands us the ip header, not the gre header */
	ip6[0] = vlib_buffer_get_current (b[0]);
	gre[0] = (void *) (ip6[0] + 1);
	vlib_buffer_advance (b[0], sizeof (ip6[0]) + sizeof (gre[0]));
	}
	else
	{
	/* ip4_local hands us the ip header, not the gre header */
	ip4[0] = vlib_buffer_get_current (b[0]);
	gre[0] = (void *) (ip4[0] + 1);
	vlib_buffer_advance (b[0], sizeof (ip4[0]) + sizeof (gre[0]));
	}

	if (PREDICT_TRUE (cached_protocol == gre[0]->protocol))
	{
	nidx[0] = cached_next_index;
	}
	else
	{
	cached_next_index = nidx[0] =
	sparse_vec_index (gm->next_by_protocol, gre[0]->protocol);
	cached_protocol = gre[0]->protocol;
	}

	ni[0] = vec_elt (gm->next_by_protocol, nidx[0]);
	next[0] = ni[0].next_index;
	type[0] = ni[0].tunnel_type;

	b[0]->error = nidx[0] == SPARSE_VEC_INVALID_INDEX
	? node->errors[GRE_ERROR_UNKNOWN_PROTOCOL]
	: node->errors[GRE_ERROR_NONE];

	version[0] = clib_net_to_host_u16 (gre[0]->flags_and_version);
	version[0] &= GRE_VERSION_MASK;

	b[0]->error = version[0]
	? node->errors[GRE_ERROR_UNSUPPORTED_VERSION] : b[0]->error;
	next[0] = version[0] ? GRE_INPUT_NEXT_DROP : next[0];

	len[0] = vlib_buffer_length_in_chain (vm, b[0]);

	if (is_ipv6)
	{
	gre_mk_key6 (&ip6[0]->dst_address,
	&ip6[0]->src_address,
	vnet_buffer (b[0])->ip.fib_index,
	type[0], TUNNEL_MODE_P2P, 0, &key[0].gtk_v6);
	matched[0] = gre_match_key6 (&cached_key.gtk_v6, &key[0].gtk_v6);
	}
	else
	{
	gre_mk_key4 (ip4[0]->dst_address,
	ip4[0]->src_address,
	vnet_buffer (b[0])->ip.fib_index,
	type[0], TUNNEL_MODE_P2P, 0, &key[0].gtk_v4);
	matched[0] = gre_match_key4 (&cached_key.gtk_v4, &key[0].gtk_v4);
	}

	tun_sw_if_index[0] = cached_tun_sw_if_index;
	if (PREDICT_FALSE (!matched[0]))
	gre_tunnel_get (gm, node, b[0], &next[0], &key[0], &cached_key,
	&tun_sw_if_index[0], &cached_tun_sw_if_index,
	is_ipv6);

	if (PREDICT_TRUE (next[0] > GRE_INPUT_NEXT_DROP))
	{
	vlib_increment_combined_counter (&gm->vnet_main->
	interface_main.combined_sw_if_counters
	[VNET_INTERFACE_COUNTER_RX],
	vm->thread_index,
	tun_sw_if_index[0],
	1 /* packets */ ,
	len[0] /* bytes */ );
	vnet_buffer (b[0])->sw_if_index[VLIB_RX] = tun_sw_if_index[0];
	}

	if (PREDICT_FALSE (b[0]->flags & VLIB_BUFFER_IS_TRACED))
	gre_trace (vm, node, b[0], tun_sw_if_index[0], ip6[0], ip4[0],
	is_ipv6);

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

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

	vlib_node_increment_counter (vm,
	is_ipv6 ? gre6_input_node.index :
	gre4_input_node.index, GRE_ERROR_PKTS_DECAP,
	n_left_from);

	return frame->n_vectors;
	}

	VLIB_NODE_FN (gre4_input_node) (vlib_main_t * vm,
	vlib_node_runtime_t * node,
	vlib_frame_t * from_frame)
	{
	return gre_input (vm, node, from_frame, /* is_ip6 */ 0);
	}

	VLIB_NODE_FN (gre6_input_node) (vlib_main_t * vm,
	vlib_node_runtime_t * node,
	vlib_frame_t * from_frame)
	{
	return gre_input (vm, node, from_frame, /* is_ip6 */ 1);
	}

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

	/* INDENT-OFF */
	VLIB_REGISTER_NODE (gre4_input_node) = {
	.name = "gre4-input",
	/* Takes a vector of packets. */
	.vector_size = sizeof (u32),

	.n_errors = GRE_N_ERROR,
	.error_strings = gre_error_strings,

	.n_next_nodes = GRE_INPUT_N_NEXT,
	.next_nodes = {
	#define _(s,n) [GRE_INPUT_NEXT_##s] = n,
	foreach_gre_input_next
	#undef _
	},

	.format_buffer = format_gre_header_with_length,
	.format_trace = format_gre_rx_trace,
	.unformat_buffer = unformat_gre_header,
	};

	VLIB_REGISTER_NODE (gre6_input_node) = {
	.name = "gre6-input",
	/* Takes a vector of packets. */
	.vector_size = sizeof (u32),

	.runtime_data_bytes = sizeof (gre_input_runtime_t),

	.n_errors = GRE_N_ERROR,
	.error_strings = gre_error_strings,

	.n_next_nodes = GRE_INPUT_N_NEXT,
	.next_nodes = {
	#define _(s,n) [GRE_INPUT_NEXT_##s] = n,
	foreach_gre_input_next
	#undef _
	},

	.format_buffer = format_gre_header_with_length,
	.format_trace = format_gre_rx_trace,
	.unformat_buffer = unformat_gre_header,
	};
	/* INDENT-ON */

	#ifndef CLIB_MARCH_VARIANT
	void
	gre_register_input_protocol (vlib_main_t * vm,
	gre_protocol_t protocol, u32 node_index,
	gre_tunnel_type_t tunnel_type)
	{
	gre_main_t *em = &gre_main;
	gre_protocol_info_t *pi;
	next_info_t *n;
	u32 i;

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

	pi = gre_get_protocol_info (em, protocol);
	pi->node_index = node_index;
	pi->tunnel_type = tunnel_type;
	pi->next_index = vlib_node_add_next (vm, gre4_input_node.index, node_index);
	i = vlib_node_add_next (vm, gre6_input_node.index, node_index);
	ASSERT (i == pi->next_index);

	/* Setup gre protocol -> next index sparse vector mapping. */
	n = sparse_vec_validate (em->next_by_protocol,
	clib_host_to_net_u16 (protocol));
	n->next_index = pi->next_index;
	n->tunnel_type = tunnel_type;
	}

	static void
	gre_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_gre_header_with_length;
	n->unformat_buffer = unformat_gre_header;
	pn->unformat_edit = unformat_pg_gre_header;
	}

	static clib_error_t *
	gre_input_init (vlib_main_t * vm)
	{
	gre_main_t *gm = &gre_main;
	vlib_node_t ethernet_input, ip4_input, ip6_input, mpls_unicast_input;

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

	gre_setup_node (vm, gre4_input_node.index);
	gre_setup_node (vm, gre6_input_node.index);

	gm->next_by_protocol = sparse_vec_new
	( /* elt bytes */ sizeof (gm->next_by_protocol[0]),
	/* bits in index / BITS (((gre_header_t ) 0)->protocol));

	/* These could be moved to the supported protocol input node defn's */
	ethernet_input = vlib_get_node_by_name (vm, (u8 *) "ethernet-input");
	ASSERT (ethernet_input);
	ip4_input = vlib_get_node_by_name (vm, (u8 *) "ip4-input");
	ASSERT (ip4_input);
	ip6_input = vlib_get_node_by_name (vm, (u8 *) "ip6-input");
	ASSERT (ip6_input);
	mpls_unicast_input = vlib_get_node_by_name (vm, (u8 *) "mpls-input");
	ASSERT (mpls_unicast_input);

	gre_register_input_protocol (vm, GRE_PROTOCOL_teb,
	ethernet_input->index, GRE_TUNNEL_TYPE_TEB);

	gre_register_input_protocol (vm, GRE_PROTOCOL_ip4,
	ip4_input->index, GRE_TUNNEL_TYPE_L3);

	gre_register_input_protocol (vm, GRE_PROTOCOL_ip6,
	ip6_input->index, GRE_TUNNEL_TYPE_L3);

	gre_register_input_protocol (vm, GRE_PROTOCOL_mpls_unicast,
	mpls_unicast_input->index, GRE_TUNNEL_TYPE_L3);

	return 0;
	}

	VLIB_INIT_FUNCTION (gre_input_init);

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