decap.c

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/*
 * decap.c: vxlan gbp tunnel decap packet processing
 *
 * Copyright (c) 2018 Cisco and/or its affiliates.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or 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/vxlan-gbp/vxlan_gbp.h>

vlib_node_registration_t vxlan4_gbp_input_node;
vlib_node_registration_t vxlan6_gbp_input_node;

typedef struct
{
  u32 next_index;
  u32 tunnel_index;
  u32 error;
  u32 vni;
  u16 sclass;
} vxlan_gbp_rx_trace_t;

static u8 *
format_vxlan_gbp_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 *);
  vxlan_gbp_rx_trace_t *t = va_arg (*args, vxlan_gbp_rx_trace_t *);

  if (t->tunnel_index == ~0)
    return format (s,
                   "VXLAN_GBP decap error - tunnel for vni %d does not exist",
                   t->vni);
  return format (s,
                 "VXLAN_GBP decap from vxlan_gbp_tunnel%d vni %d sclass %d"
                 " next %d error %d",
                 t->tunnel_index, t->vni, t->sclass, t->next_index, t->error);
}

always_inline u32
buf_fib_index (vlib_buffer_t * b, u32 is_ip4)
{
  u32 sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_TX];
  if (sw_if_index != (u32) ~ 0)
    return sw_if_index;

  u32 *fib_index_by_sw_if_index = is_ip4 ?
    ip4_main.fib_index_by_sw_if_index : ip6_main.fib_index_by_sw_if_index;
  sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX];

  return vec_elt (fib_index_by_sw_if_index, sw_if_index);
}

typedef vxlan4_gbp_tunnel_key_t last_tunnel_cache4;

always_inline vxlan_gbp_tunnel_t *
vxlan4_gbp_find_tunnel (vxlan_gbp_main_t * vxm, last_tunnel_cache4 * cache,
                        u32 fib_index, ip4_header_t * ip4_0,
                        vxlan_gbp_header_t * vxlan_gbp0,
                        vxlan_gbp_tunnel_t ** stats_t0)
{
  /* Make sure VXLAN_GBP tunnel exist according to packet SIP and VNI */
  vxlan4_gbp_tunnel_key_t key4;
  key4.key[1] = ((u64) fib_index << 32) | vxlan_gbp0->vni_reserved;

  if (PREDICT_FALSE (key4.key[1] != cache->key[1] ||
                     ip4_0->src_address.as_u32 != (u32) cache->key[0]))
    {
      key4.key[0] = ip4_0->src_address.as_u32;
      int rv = clib_bihash_search_inline_16_8 (&vxm->vxlan4_gbp_tunnel_by_key,
                                               &key4);
      if (PREDICT_FALSE (rv != 0))
        return 0;

      *cache = key4;
    }
  vxlan_gbp_tunnel_t *t0 = pool_elt_at_index (vxm->tunnels, cache->value);

  /* Validate VXLAN_GBP tunnel SIP against packet DIP */
  if (PREDICT_TRUE (ip4_0->dst_address.as_u32 == t0->src.ip4.as_u32))
    *stats_t0 = t0;
  else
    {
      /* try multicast */
      if (PREDICT_TRUE (!ip4_address_is_multicast (&ip4_0->dst_address)))
        return 0;

      key4.key[0] = ip4_0->dst_address.as_u32;
      /* Make sure mcast VXLAN_GBP tunnel exist by packet DIP and VNI */
      int rv = clib_bihash_search_inline_16_8 (&vxm->vxlan4_gbp_tunnel_by_key,
                                               &key4);
      if (PREDICT_FALSE (rv != 0))
        return 0;

      *stats_t0 = pool_elt_at_index (vxm->tunnels, key4.value);
    }

  return t0;
}

typedef vxlan6_gbp_tunnel_key_t last_tunnel_cache6;

always_inline vxlan_gbp_tunnel_t *
vxlan6_gbp_find_tunnel (vxlan_gbp_main_t * vxm, last_tunnel_cache6 * cache,
                        u32 fib_index, ip6_header_t * ip6_0,
                        vxlan_gbp_header_t * vxlan_gbp0,
                        vxlan_gbp_tunnel_t ** stats_t0)
{
  /* Make sure VXLAN_GBP tunnel exist according to packet SIP and VNI */
  vxlan6_gbp_tunnel_key_t key6 = {
    .key = {
            [0] = ip6_0->src_address.as_u64[0],
            [1] = ip6_0->src_address.as_u64[1],
            [2] = (((u64) fib_index) << 32) | vxlan_gbp0->vni_reserved,
            }
  };

  if (PREDICT_FALSE
      (clib_bihash_key_compare_24_8 (key6.key, cache->key) == 0))
    {
      int rv = clib_bihash_search_inline_24_8 (&vxm->vxlan6_gbp_tunnel_by_key,
                                               &key6);
      if (PREDICT_FALSE (rv != 0))
        return 0;

      *cache = key6;
    }
  vxlan_gbp_tunnel_t *t0 = pool_elt_at_index (vxm->tunnels, cache->value);

  /* Validate VXLAN_GBP tunnel SIP against packet DIP */
  if (PREDICT_TRUE (ip6_address_is_equal (&ip6_0->dst_address, &t0->src.ip6)))
    *stats_t0 = t0;
  else
    {
      /* try multicast */
      if (PREDICT_TRUE (!ip6_address_is_multicast (&ip6_0->dst_address)))
        return 0;

      /* Make sure mcast VXLAN_GBP tunnel exist by packet DIP and VNI */
      key6.key[0] = ip6_0->dst_address.as_u64[0];
      key6.key[1] = ip6_0->dst_address.as_u64[1];
      int rv = clib_bihash_search_inline_24_8 (&vxm->vxlan6_gbp_tunnel_by_key,
                                               &key6);
      if (PREDICT_FALSE (rv != 0))
        return 0;

      *stats_t0 = pool_elt_at_index (vxm->tunnels, key6.value);
    }

  return t0;
}

always_inline uword
vxlan_gbp_input (vlib_main_t * vm,
                 vlib_node_runtime_t * node,
                 vlib_frame_t * from_frame, u32 is_ip4)
{
  vxlan_gbp_main_t *vxm = &vxlan_gbp_main;
  vnet_main_t *vnm = vxm->vnet_main;
  vnet_interface_main_t *im = &vnm->interface_main;
  vlib_combined_counter_main_t *rx_counter =
    im->combined_sw_if_counters + VNET_INTERFACE_COUNTER_RX;
  vlib_combined_counter_main_t *drop_counter =
    im->combined_sw_if_counters + VNET_INTERFACE_COUNTER_DROP;
  last_tunnel_cache4 last4;
  last_tunnel_cache6 last6;
  u32 pkts_decapsulated = 0;
  u32 thread_index = vlib_get_thread_index ();

  if (is_ip4)
    memset (&last4, 0xff, sizeof last4);
  else
    memset (&last6, 0xff, sizeof last6);

  u32 next_index = node->cached_next_index;

  u32 *from = vlib_frame_vector_args (from_frame);
  u32 n_left_from = from_frame->n_vectors;

  while (n_left_from > 0)
    {
      u32 *to_next, 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)
        {
          /* 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, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
            CLIB_PREFETCH (p3->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
          }

          u32 bi0 = to_next[0] = from[0];
          u32 bi1 = to_next[1] = from[1];
          from += 2;
          to_next += 2;
          n_left_to_next -= 2;
          n_left_from -= 2;

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

          /* udp leaves current_data pointing at the vxlan_gbp header */
          void *cur0 = vlib_buffer_get_current (b0);
          void *cur1 = vlib_buffer_get_current (b1);
          vxlan_gbp_header_t *vxlan_gbp0 = cur0;
          vxlan_gbp_header_t *vxlan_gbp1 = cur1;

          ip4_header_t *ip4_0, *ip4_1;
          ip6_header_t *ip6_0, *ip6_1;
          if (is_ip4)
            {
              ip4_0 = cur0 - sizeof (udp_header_t) - sizeof (ip4_header_t);
              ip4_1 = cur1 - sizeof (udp_header_t) - sizeof (ip4_header_t);
            }
          else
            {
              ip6_0 = cur0 - sizeof (udp_header_t) - sizeof (ip6_header_t);
              ip6_1 = cur1 - sizeof (udp_header_t) - sizeof (ip6_header_t);
            }

          /* pop vxlan_gbp */
          vlib_buffer_advance (b0, sizeof *vxlan_gbp0);
          vlib_buffer_advance (b1, sizeof *vxlan_gbp1);

          u32 fi0 = buf_fib_index (b0, is_ip4);
          u32 fi1 = buf_fib_index (b1, is_ip4);

          vxlan_gbp_tunnel_t *t0, *stats_t0 = 0;
          vxlan_gbp_tunnel_t *t1, *stats_t1 = 0;
          if (is_ip4)
            {
              t0 =
                vxlan4_gbp_find_tunnel (vxm, &last4, fi0, ip4_0, vxlan_gbp0,
                                        &stats_t0);
              t1 =
                vxlan4_gbp_find_tunnel (vxm, &last4, fi1, ip4_1, vxlan_gbp1,
                                        &stats_t1);
            }
          else
            {
              t0 =
                vxlan6_gbp_find_tunnel (vxm, &last6, fi0, ip6_0, vxlan_gbp0,
                                        &stats_t0);
              t1 =
                vxlan6_gbp_find_tunnel (vxm, &last6, fi1, ip6_1, vxlan_gbp1,
                                        &stats_t1);
            }

          u32 len0 = vlib_buffer_length_in_chain (vm, b0);
          u32 len1 = vlib_buffer_length_in_chain (vm, b1);

          u32 next0, next1;
          u8 error0 = 0, error1 = 0;
          u8 flags0 = vxlan_gbp_get_flags (vxlan_gbp0);
          u8 flags1 = vxlan_gbp_get_flags (vxlan_gbp1);
          /* Validate VXLAN_GBP tunnel encap-fib index against packet */
          if (PREDICT_FALSE
              (t0 == 0 || flags0 != (VXLAN_GBP_FLAGS_I | VXLAN_GBP_FLAGS_G)))
            {
              next0 = VXLAN_GBP_INPUT_NEXT_DROP;

              if (t0 != 0
                  && flags0 != (VXLAN_GBP_FLAGS_I | VXLAN_GBP_FLAGS_G))
                {
                  error0 = VXLAN_GBP_ERROR_BAD_FLAGS;
                  vlib_increment_combined_counter
                    (drop_counter, thread_index, stats_t0->sw_if_index, 1,
                     len0);
                }
              else
                error0 = VXLAN_GBP_ERROR_NO_SUCH_TUNNEL;
              b0->error = node->errors[error0];
            }
          else
            {
              next0 = t0->decap_next_index;
              vnet_buffer2 (b0)->gbp.flags =
                vxlan_gbp_get_gpflags (vxlan_gbp0);
              vnet_buffer2 (b0)->gbp.src_epg =
                vxlan_gbp_get_sclass (vxlan_gbp0);

              /* Required to make the l2 tag push / pop code work on l2 subifs */
              if (PREDICT_TRUE (next0 == VXLAN_GBP_INPUT_NEXT_L2_INPUT))
                vnet_update_l2_len (b0);

              /* Set packet input sw_if_index to unicast VXLAN tunnel for learning */
              vnet_buffer (b0)->sw_if_index[VLIB_RX] = t0->sw_if_index;
              vlib_increment_combined_counter
                (rx_counter, thread_index, stats_t0->sw_if_index, 1, len0);
              pkts_decapsulated++;
            }

          /* Validate VXLAN_GBP tunnel encap-fib index against packet */
          if (PREDICT_FALSE
              (t1 == 0 || flags1 != (VXLAN_GBP_FLAGS_I | VXLAN_GBP_FLAGS_G)))
            {
              next1 = VXLAN_GBP_INPUT_NEXT_DROP;

              if (t1 != 0
                  && flags1 != (VXLAN_GBP_FLAGS_I | VXLAN_GBP_FLAGS_G))
                {
                  error1 = VXLAN_GBP_ERROR_BAD_FLAGS;
                  vlib_increment_combined_counter
                    (drop_counter, thread_index, stats_t1->sw_if_index, 1,
                     len1);
                }
              else
                error1 = VXLAN_GBP_ERROR_NO_SUCH_TUNNEL;
              b1->error = node->errors[error1];
            }
          else
            {
              next1 = t1->decap_next_index;
              vnet_buffer2 (b1)->gbp.flags =
                vxlan_gbp_get_gpflags (vxlan_gbp1);
              vnet_buffer2 (b1)->gbp.src_epg =
                vxlan_gbp_get_sclass (vxlan_gbp1);

              /* Required to make the l2 tag push / pop code work on l2 subifs */
              if (PREDICT_TRUE (next1 == VXLAN_GBP_INPUT_NEXT_L2_INPUT))
                vnet_update_l2_len (b1);

              /* Set packet input sw_if_index to unicast VXLAN_GBP tunnel for learning */
              vnet_buffer (b1)->sw_if_index[VLIB_RX] = t1->sw_if_index;
              pkts_decapsulated++;

              vlib_increment_combined_counter
                (rx_counter, thread_index, stats_t1->sw_if_index, 1, len1);
            }

          if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
            {
              vxlan_gbp_rx_trace_t *tr =
                vlib_add_trace (vm, node, b0, sizeof (*tr));
              tr->next_index = next0;
              tr->error = error0;
              tr->tunnel_index = t0 == 0 ? ~0 : t0 - vxm->tunnels;
              tr->vni = vxlan_gbp_get_vni (vxlan_gbp0);
              tr->sclass = vxlan_gbp_get_sclass (vxlan_gbp0);
            }
          if (PREDICT_FALSE (b1->flags & VLIB_BUFFER_IS_TRACED))
            {
              vxlan_gbp_rx_trace_t *tr =
                vlib_add_trace (vm, node, b1, sizeof (*tr));
              tr->next_index = next1;
              tr->error = error1;
              tr->tunnel_index = t1 == 0 ? ~0 : t1 - vxm->tunnels;
              tr->vni = vxlan_gbp_get_vni (vxlan_gbp1);
              tr->sclass = vxlan_gbp_get_sclass (vxlan_gbp1);
            }

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

          vlib_buffer_t *b0 = vlib_get_buffer (vm, bi0);

          /* udp leaves current_data pointing at the vxlan_gbp header */
          void *cur0 = vlib_buffer_get_current (b0);
          vxlan_gbp_header_t *vxlan_gbp0 = cur0;
          ip4_header_t *ip4_0;
          ip6_header_t *ip6_0;
          if (is_ip4)
            ip4_0 = cur0 - sizeof (udp_header_t) - sizeof (ip4_header_t);
          else
            ip6_0 = cur0 - sizeof (udp_header_t) - sizeof (ip6_header_t);

          /* pop (ip, udp, vxlan_gbp) */
          vlib_buffer_advance (b0, sizeof (*vxlan_gbp0));

          u32 fi0 = buf_fib_index (b0, is_ip4);

          vxlan_gbp_tunnel_t *t0, *stats_t0 = 0;
          if (is_ip4)
            t0 =
              vxlan4_gbp_find_tunnel (vxm, &last4, fi0, ip4_0, vxlan_gbp0,
                                      &stats_t0);
          else
            t0 =
              vxlan6_gbp_find_tunnel (vxm, &last6, fi0, ip6_0, vxlan_gbp0,
                                      &stats_t0);

          uword len0 = vlib_buffer_length_in_chain (vm, b0);

          u32 next0;
          u8 error0 = 0;
          u8 flags0 = vxlan_gbp_get_flags (vxlan_gbp0);
          /* Validate VXLAN_GBP tunnel encap-fib index against packet */
          if (PREDICT_FALSE
              (t0 == 0 || flags0 != (VXLAN_GBP_FLAGS_I | VXLAN_GBP_FLAGS_G)))
            {
              next0 = VXLAN_GBP_INPUT_NEXT_DROP;

              if (t0 != 0
                  && flags0 != (VXLAN_GBP_FLAGS_I | VXLAN_GBP_FLAGS_G))
                {
                  error0 = VXLAN_GBP_ERROR_BAD_FLAGS;
                  vlib_increment_combined_counter
                    (drop_counter, thread_index, stats_t0->sw_if_index, 1,
                     len0);
                }
              else
                error0 = VXLAN_GBP_ERROR_NO_SUCH_TUNNEL;
              b0->error = node->errors[error0];
            }
          else
            {
              next0 = t0->decap_next_index;
              vnet_buffer2 (b0)->gbp.flags =
                vxlan_gbp_get_gpflags (vxlan_gbp0);
              vnet_buffer2 (b0)->gbp.src_epg =
                vxlan_gbp_get_sclass (vxlan_gbp0);


              /* Required to make the l2 tag push / pop code work on l2 subifs */
              if (PREDICT_TRUE (next0 == VXLAN_GBP_INPUT_NEXT_L2_INPUT))
                vnet_update_l2_len (b0);

              /* Set packet input sw_if_index to unicast VXLAN_GBP tunnel for learning */
              vnet_buffer (b0)->sw_if_index[VLIB_RX] = t0->sw_if_index;
              pkts_decapsulated++;

              vlib_increment_combined_counter
                (rx_counter, thread_index, stats_t0->sw_if_index, 1, len0);
            }

          if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
            {
              vxlan_gbp_rx_trace_t *tr
                = vlib_add_trace (vm, node, b0, sizeof (*tr));
              tr->next_index = next0;
              tr->error = error0;
              tr->tunnel_index = t0 == 0 ? ~0 : t0 - vxm->tunnels;
              tr->vni = vxlan_gbp_get_vni (vxlan_gbp0);
              tr->sclass = vxlan_gbp_get_sclass (vxlan_gbp0);
            }
          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);
    }
  /* Do we still need this now that tunnel tx stats is kept? */
  u32 node_idx =
    is_ip4 ? vxlan4_gbp_input_node.index : vxlan6_gbp_input_node.index;
  vlib_node_increment_counter (vm, node_idx, VXLAN_GBP_ERROR_DECAPSULATED,
                               pkts_decapsulated);

  return from_frame->n_vectors;
}

static uword
vxlan4_gbp_input (vlib_main_t * vm,
                  vlib_node_runtime_t * node, vlib_frame_t * from_frame)
{
  return vxlan_gbp_input (vm, node, from_frame, /* is_ip4 */ 1);
}

static uword
vxlan6_gbp_input (vlib_main_t * vm,
                  vlib_node_runtime_t * node, vlib_frame_t * from_frame)
{
  return vxlan_gbp_input (vm, node, from_frame, /* is_ip4 */ 0);
}

static char *vxlan_gbp_error_strings[] = {
#define vxlan_gbp_error(n,s) s,
#include <vnet/vxlan-gbp/vxlan_gbp_error.def>
#undef vxlan_gbp_error
#undef _
};

/* *INDENT-OFF* */
VLIB_REGISTER_NODE (vxlan4_gbp_input_node) =
{
  .function = vxlan4_gbp_input,
  .name = "vxlan4-gbp-input",
  .vector_size = sizeof (u32),
  .n_errors = VXLAN_GBP_N_ERROR,
  .error_strings = vxlan_gbp_error_strings,
  .n_next_nodes = VXLAN_GBP_INPUT_N_NEXT,
  .format_trace = format_vxlan_gbp_rx_trace,
  .next_nodes = {
#define _(s,n) [VXLAN_GBP_INPUT_NEXT_##s] = n,
    foreach_vxlan_gbp_input_next
#undef _
  },
};
VLIB_NODE_FUNCTION_MULTIARCH (vxlan4_gbp_input_node, vxlan4_gbp_input)

VLIB_REGISTER_NODE (vxlan6_gbp_input_node) =
{
  .function = vxlan6_gbp_input,
  .name = "vxlan6-gbp-input",
  .vector_size = sizeof (u32),
  .n_errors = VXLAN_GBP_N_ERROR,
  .error_strings = vxlan_gbp_error_strings,
  .n_next_nodes = VXLAN_GBP_INPUT_N_NEXT,
  .next_nodes = {
#define _(s,n) [VXLAN_GBP_INPUT_NEXT_##s] = n,
    foreach_vxlan_gbp_input_next
#undef _
  },
  .format_trace = format_vxlan_gbp_rx_trace,
};
VLIB_NODE_FUNCTION_MULTIARCH (vxlan6_gbp_input_node, vxlan6_gbp_input)
/* *INDENT-ON* */

typedef enum
{
  IP_VXLAN_GBP_BYPASS_NEXT_DROP,
  IP_VXLAN_GBP_BYPASS_NEXT_VXLAN_GBP,
  IP_VXLAN_GBP_BYPASS_N_NEXT,
} ip_vxan_gbp_bypass_next_t;

always_inline uword
ip_vxlan_gbp_bypass_inline (vlib_main_t * vm,
                            vlib_node_runtime_t * node,
                            vlib_frame_t * frame, u32 is_ip4)
{
  vxlan_gbp_main_t *vxm = &vxlan_gbp_main;
  u32 *from, *to_next, n_left_from, n_left_to_next, next_index;
  vlib_node_runtime_t *error_node =
    vlib_node_get_runtime (vm, ip4_input_node.index);
  ip4_address_t addr4;          /* last IPv4 address matching a local VTEP address */
  ip6_address_t addr6;          /* last IPv6 address matching a local VTEP address */

  from = vlib_frame_vector_args (frame);
  n_left_from = frame->n_vectors;
  next_index = node->cached_next_index;

  if (node->flags & VLIB_NODE_FLAG_TRACE)
    ip4_forward_next_trace (vm, node, frame, VLIB_TX);

  if (is_ip4)
    addr4.data_u32 = ~0;
  else
    ip6_address_set_zero (&addr6);

  while (n_left_from > 0)
    {
      vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);

      while (n_left_from >= 4 && n_left_to_next >= 2)
        {
          vlib_buffer_t *b0, *b1;
          ip4_header_t *ip40, *ip41;
          ip6_header_t *ip60, *ip61;
          udp_header_t *udp0, *udp1;
          u32 bi0, ip_len0, udp_len0, flags0, next0;
          u32 bi1, ip_len1, udp_len1, flags1, next1;
          i32 len_diff0, len_diff1;
          u8 error0, good_udp0, proto0;
          u8 error1, good_udp1, proto1;

          /* 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, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
            CLIB_PREFETCH (p3->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
          }

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

          b0 = vlib_get_buffer (vm, bi0);
          b1 = vlib_get_buffer (vm, bi1);
          if (is_ip4)
            {
              ip40 = vlib_buffer_get_current (b0);
              ip41 = vlib_buffer_get_current (b1);
            }
          else
            {
              ip60 = vlib_buffer_get_current (b0);
              ip61 = vlib_buffer_get_current (b1);
            }

          /* Setup packet for next IP feature */
          vnet_feature_next (&next0, b0);
          vnet_feature_next (&next1, b1);

          if (is_ip4)
            {
              /* Treat IP frag packets as "experimental" protocol for now
                 until support of IP frag reassembly is implemented */
              proto0 = ip4_is_fragment (ip40) ? 0xfe : ip40->protocol;
              proto1 = ip4_is_fragment (ip41) ? 0xfe : ip41->protocol;
            }
          else
            {
              proto0 = ip60->protocol;
              proto1 = ip61->protocol;
            }

          /* Process packet 0 */
          if (proto0 != IP_PROTOCOL_UDP)
            goto exit0;         /* not UDP packet */

          if (is_ip4)
            udp0 = ip4_next_header (ip40);
          else
            udp0 = ip6_next_header (ip60);

          if (udp0->dst_port != clib_host_to_net_u16 (UDP_DST_PORT_vxlan_gbp))
            goto exit0;         /* not VXLAN_GBP packet */

          /* Validate DIP against VTEPs */
          if (is_ip4)
            {
              if (addr4.as_u32 != ip40->dst_address.as_u32)
                {
                  if (!hash_get (vxm->vtep4, ip40->dst_address.as_u32))
                    goto exit0; /* no local VTEP for VXLAN_GBP packet */
                  addr4 = ip40->dst_address;
                }
            }
          else
            {
              if (!ip6_address_is_equal (&addr6, &ip60->dst_address))
                {
                  if (!hash_get_mem (vxm->vtep6, &ip60->dst_address))
                    goto exit0; /* no local VTEP for VXLAN_GBP packet */
                  addr6 = ip60->dst_address;
                }
            }

          flags0 = b0->flags;
          good_udp0 = (flags0 & VNET_BUFFER_F_L4_CHECKSUM_CORRECT) != 0;

          /* Don't verify UDP checksum for packets with explicit zero checksum. */
          good_udp0 |= udp0->checksum == 0;

          /* Verify UDP length */
          if (is_ip4)
            ip_len0 = clib_net_to_host_u16 (ip40->length);
          else
            ip_len0 = clib_net_to_host_u16 (ip60->payload_length);
          udp_len0 = clib_net_to_host_u16 (udp0->length);
          len_diff0 = ip_len0 - udp_len0;

          /* Verify UDP checksum */
          if (PREDICT_FALSE (!good_udp0))
            {
              if ((flags0 & VNET_BUFFER_F_L4_CHECKSUM_COMPUTED) == 0)
                {
                  if (is_ip4)
                    flags0 = ip4_tcp_udp_validate_checksum (vm, b0);
                  else
                    flags0 = ip6_tcp_udp_icmp_validate_checksum (vm, b0);
                  good_udp0 =
                    (flags0 & VNET_BUFFER_F_L4_CHECKSUM_CORRECT) != 0;
                }
            }

          if (is_ip4)
            {
              error0 = good_udp0 ? 0 : IP4_ERROR_UDP_CHECKSUM;
              error0 = (len_diff0 >= 0) ? error0 : IP4_ERROR_UDP_LENGTH;
            }
          else
            {
              error0 = good_udp0 ? 0 : IP6_ERROR_UDP_CHECKSUM;
              error0 = (len_diff0 >= 0) ? error0 : IP6_ERROR_UDP_LENGTH;
            }

          next0 = error0 ?
            IP_VXLAN_GBP_BYPASS_NEXT_DROP :
            IP_VXLAN_GBP_BYPASS_NEXT_VXLAN_GBP;
          b0->error = error0 ? error_node->errors[error0] : 0;

          /* vxlan-gbp-input node expect current at VXLAN_GBP header */
          if (is_ip4)
            vlib_buffer_advance (b0,
                                 sizeof (ip4_header_t) +
                                 sizeof (udp_header_t));
          else
            vlib_buffer_advance (b0,
                                 sizeof (ip6_header_t) +
                                 sizeof (udp_header_t));

        exit0:
          /* Process packet 1 */
          if (proto1 != IP_PROTOCOL_UDP)
            goto exit1;         /* not UDP packet */

          if (is_ip4)
            udp1 = ip4_next_header (ip41);
          else
            udp1 = ip6_next_header (ip61);

          if (udp1->dst_port != clib_host_to_net_u16 (UDP_DST_PORT_vxlan_gbp))
            goto exit1;         /* not VXLAN_GBP packet */

          /* Validate DIP against VTEPs */
          if (is_ip4)
            {
              if (addr4.as_u32 != ip41->dst_address.as_u32)
                {
                  if (!hash_get (vxm->vtep4, ip41->dst_address.as_u32))
                    goto exit1; /* no local VTEP for VXLAN_GBP packet */
                  addr4 = ip41->dst_address;
                }
            }
          else
            {
              if (!ip6_address_is_equal (&addr6, &ip61->dst_address))
                {
                  if (!hash_get_mem (vxm->vtep6, &ip61->dst_address))
                    goto exit1; /* no local VTEP for VXLAN_GBP packet */
                  addr6 = ip61->dst_address;
                }
            }

          flags1 = b1->flags;
          good_udp1 = (flags1 & VNET_BUFFER_F_L4_CHECKSUM_CORRECT) != 0;

          /* Don't verify UDP checksum for packets with explicit zero checksum. */
          good_udp1 |= udp1->checksum == 0;

          /* Verify UDP length */
          if (is_ip4)
            ip_len1 = clib_net_to_host_u16 (ip41->length);
          else
            ip_len1 = clib_net_to_host_u16 (ip61->payload_length);
          udp_len1 = clib_net_to_host_u16 (udp1->length);
          len_diff1 = ip_len1 - udp_len1;

          /* Verify UDP checksum */
          if (PREDICT_FALSE (!good_udp1))
            {
              if ((flags1 & VNET_BUFFER_F_L4_CHECKSUM_COMPUTED) == 0)
                {
                  if (is_ip4)
                    flags1 = ip4_tcp_udp_validate_checksum (vm, b1);
                  else
                    flags1 = ip6_tcp_udp_icmp_validate_checksum (vm, b1);
                  good_udp1 =
                    (flags1 & VNET_BUFFER_F_L4_CHECKSUM_CORRECT) != 0;
                }
            }

          if (is_ip4)
            {
              error1 = good_udp1 ? 0 : IP4_ERROR_UDP_CHECKSUM;
              error1 = (len_diff1 >= 0) ? error1 : IP4_ERROR_UDP_LENGTH;
            }
          else
            {
              error1 = good_udp1 ? 0 : IP6_ERROR_UDP_CHECKSUM;
              error1 = (len_diff1 >= 0) ? error1 : IP6_ERROR_UDP_LENGTH;
            }

          next1 = error1 ?
            IP_VXLAN_GBP_BYPASS_NEXT_DROP :
            IP_VXLAN_GBP_BYPASS_NEXT_VXLAN_GBP;
          b1->error = error1 ? error_node->errors[error1] : 0;

          /* vxlan_gbp-input node expect current at VXLAN_GBP header */
          if (is_ip4)
            vlib_buffer_advance (b1,
                                 sizeof (ip4_header_t) +
                                 sizeof (udp_header_t));
          else
            vlib_buffer_advance (b1,
                                 sizeof (ip6_header_t) +
                                 sizeof (udp_header_t));

        exit1:
          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)
        {
          vlib_buffer_t *b0;
          ip4_header_t *ip40;
          ip6_header_t *ip60;
          udp_header_t *udp0;
          u32 bi0, ip_len0, udp_len0, flags0, next0;
          i32 len_diff0;
          u8 error0, good_udp0, proto0;

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

          b0 = vlib_get_buffer (vm, bi0);
          if (is_ip4)
            ip40 = vlib_buffer_get_current (b0);
          else
            ip60 = vlib_buffer_get_current (b0);

          /* Setup packet for next IP feature */
          vnet_feature_next (&next0, b0);

          if (is_ip4)
            /* Treat IP4 frag packets as "experimental" protocol for now
               until support of IP frag reassembly is implemented */
            proto0 = ip4_is_fragment (ip40) ? 0xfe : ip40->protocol;
          else
            proto0 = ip60->protocol;

          if (proto0 != IP_PROTOCOL_UDP)
            goto exit;          /* not UDP packet */

          if (is_ip4)
            udp0 = ip4_next_header (ip40);
          else
            udp0 = ip6_next_header (ip60);

          if (udp0->dst_port != clib_host_to_net_u16 (UDP_DST_PORT_vxlan_gbp))
            goto exit;          /* not VXLAN_GBP packet */

          /* Validate DIP against VTEPs */
          if (is_ip4)
            {
              if (addr4.as_u32 != ip40->dst_address.as_u32)
                {
                  if (!hash_get (vxm->vtep4, ip40->dst_address.as_u32))
                    goto exit;  /* no local VTEP for VXLAN_GBP packet */
                  addr4 = ip40->dst_address;
                }
            }
          else
            {
              if (!ip6_address_is_equal (&addr6, &ip60->dst_address))
                {
                  if (!hash_get_mem (vxm->vtep6, &ip60->dst_address))
                    goto exit;  /* no local VTEP for VXLAN_GBP packet */
                  addr6 = ip60->dst_address;
                }
            }

          flags0 = b0->flags;
          good_udp0 = (flags0 & VNET_BUFFER_F_L4_CHECKSUM_CORRECT) != 0;

          /* Don't verify UDP checksum for packets with explicit zero checksum. */
          good_udp0 |= udp0->checksum == 0;

          /* Verify UDP length */
          if (is_ip4)
            ip_len0 = clib_net_to_host_u16 (ip40->length);
          else
            ip_len0 = clib_net_to_host_u16 (ip60->payload_length);
          udp_len0 = clib_net_to_host_u16 (udp0->length);
          len_diff0 = ip_len0 - udp_len0;

          /* Verify UDP checksum */
          if (PREDICT_FALSE (!good_udp0))
            {
              if ((flags0 & VNET_BUFFER_F_L4_CHECKSUM_COMPUTED) == 0)
                {
                  if (is_ip4)
                    flags0 = ip4_tcp_udp_validate_checksum (vm, b0);
                  else
                    flags0 = ip6_tcp_udp_icmp_validate_checksum (vm, b0);
                  good_udp0 =
                    (flags0 & VNET_BUFFER_F_L4_CHECKSUM_CORRECT) != 0;
                }
            }

          if (is_ip4)
            {
              error0 = good_udp0 ? 0 : IP4_ERROR_UDP_CHECKSUM;
              error0 = (len_diff0 >= 0) ? error0 : IP4_ERROR_UDP_LENGTH;
            }
          else
            {
              error0 = good_udp0 ? 0 : IP6_ERROR_UDP_CHECKSUM;
              error0 = (len_diff0 >= 0) ? error0 : IP6_ERROR_UDP_LENGTH;
            }

          next0 = error0 ?
            IP_VXLAN_GBP_BYPASS_NEXT_DROP :
            IP_VXLAN_GBP_BYPASS_NEXT_VXLAN_GBP;
          b0->error = error0 ? error_node->errors[error0] : 0;

          /* vxlan_gbp-input node expect current at VXLAN_GBP header */
          if (is_ip4)
            vlib_buffer_advance (b0,
                                 sizeof (ip4_header_t) +
                                 sizeof (udp_header_t));
          else
            vlib_buffer_advance (b0,
                                 sizeof (ip6_header_t) +
                                 sizeof (udp_header_t));

        exit:
          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);
    }

  return frame->n_vectors;
}

static uword
ip4_vxlan_gbp_bypass (vlib_main_t * vm,
                      vlib_node_runtime_t * node, vlib_frame_t * frame)
{
  return ip_vxlan_gbp_bypass_inline (vm, node, frame, /* is_ip4 */ 1);
}

/* *INDENT-OFF* */
VLIB_REGISTER_NODE (ip4_vxlan_gbp_bypass_node) =
{
  .function = ip4_vxlan_gbp_bypass,
  .name = "ip4-vxlan-gbp-bypass",
  .vector_size = sizeof (u32),
  .n_next_nodes = IP_VXLAN_GBP_BYPASS_N_NEXT,
  .next_nodes = {
          [IP_VXLAN_GBP_BYPASS_NEXT_DROP] = "error-drop",
          [IP_VXLAN_GBP_BYPASS_NEXT_VXLAN_GBP] = "vxlan4-gbp-input",
  },
  .format_buffer = format_ip4_header,
  .format_trace = format_ip4_forward_next_trace,
};

VLIB_NODE_FUNCTION_MULTIARCH (ip4_vxlan_gbp_bypass_node, ip4_vxlan_gbp_bypass)
/* *INDENT-ON* */

/* Dummy init function to get us linked in. */
clib_error_t *
ip4_vxlan_gbp_bypass_init (vlib_main_t * vm)
{
  return 0;
}

VLIB_INIT_FUNCTION (ip4_vxlan_gbp_bypass_init);

static uword
ip6_vxlan_gbp_bypass (vlib_main_t * vm,
                      vlib_node_runtime_t * node, vlib_frame_t * frame)
{
  return ip_vxlan_gbp_bypass_inline (vm, node, frame, /* is_ip4 */ 0);
}

/* *INDENT-OFF* */
VLIB_REGISTER_NODE (ip6_vxlan_gbp_bypass_node) =
{
  .function = ip6_vxlan_gbp_bypass,
  .name = "ip6-vxlan-gbp-bypass",
  .vector_size = sizeof (u32),
  .n_next_nodes = IP_VXLAN_GBP_BYPASS_N_NEXT,
  .next_nodes = {
    [IP_VXLAN_GBP_BYPASS_NEXT_DROP] = "error-drop",
    [IP_VXLAN_GBP_BYPASS_NEXT_VXLAN_GBP] = "vxlan6-gbp-input",
  },
  .format_buffer = format_ip6_header,
  .format_trace = format_ip6_forward_next_trace,
};

VLIB_NODE_FUNCTION_MULTIARCH (ip6_vxlan_gbp_bypass_node, ip6_vxlan_gbp_bypass)
/* *INDENT-ON* */

/* Dummy init function to get us linked in. */
clib_error_t *
ip6_vxlan_gbp_bypass_init (vlib_main_t * vm)
{
  return 0;
}

VLIB_INIT_FUNCTION (ip6_vxlan_gbp_bypass_init);

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