ip4_map_t.c

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/*
 * Copyright (c) 2015 Cisco and/or its affiliates.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
#include "map.h"

#include <vnet/ip/ip_frag.h>
#include <vnet/ip/ip4_to_ip6.h>

#define IP4_MAP_T_DUAL_LOOP 1

typedef enum
{
  IP4_MAPT_NEXT_MAPT_TCP_UDP,
  IP4_MAPT_NEXT_MAPT_ICMP,
  IP4_MAPT_NEXT_MAPT_FRAGMENTED,
  IP4_MAPT_NEXT_DROP,
  IP4_MAPT_N_NEXT
} ip4_mapt_next_t;

typedef enum
{
  IP4_MAPT_ICMP_NEXT_IP6_LOOKUP,
  IP4_MAPT_ICMP_NEXT_IP6_FRAG,
  IP4_MAPT_ICMP_NEXT_DROP,
  IP4_MAPT_ICMP_N_NEXT
} ip4_mapt_icmp_next_t;

typedef enum
{
  IP4_MAPT_TCP_UDP_NEXT_IP6_LOOKUP,
  IP4_MAPT_TCP_UDP_NEXT_IP6_FRAG,
  IP4_MAPT_TCP_UDP_NEXT_DROP,
  IP4_MAPT_TCP_UDP_N_NEXT
} ip4_mapt_tcp_udp_next_t;

typedef enum
{
  IP4_MAPT_FRAGMENTED_NEXT_IP6_LOOKUP,
  IP4_MAPT_FRAGMENTED_NEXT_IP6_FRAG,
  IP4_MAPT_FRAGMENTED_NEXT_DROP,
  IP4_MAPT_FRAGMENTED_N_NEXT
} ip4_mapt_fragmented_next_t;

//This is used to pass information within the buffer data.
//Buffer structure being too small to contain big structures like this.
/* *INDENT-OFF* */
typedef CLIB_PACKED (struct {
  ip6_address_t daddr;
  ip6_address_t saddr;
  //IPv6 header + Fragmentation header will be here
  //sizeof(ip6) + sizeof(ip_frag) - sizeof(ip4)
  u8 unused[28];
}) ip4_mapt_pseudo_header_t;
/* *INDENT-ON* */


static_always_inline int
ip4_map_fragment_cache (ip4_header_t * ip4, u16 port)
{
  u32 *ignore = NULL;
  map_ip4_reass_lock ();
  map_ip4_reass_t *r =
    map_ip4_reass_get (ip4->src_address.as_u32, ip4->dst_address.as_u32,
                       ip4->fragment_id,
                       (ip4->protocol ==
                        IP_PROTOCOL_ICMP) ? IP_PROTOCOL_ICMP6 : ip4->protocol,
                       &ignore);
  if (r)
    r->port = port;

  map_ip4_reass_unlock ();
  return !r;
}

static_always_inline i32
ip4_map_fragment_get_port (ip4_header_t * ip4)
{
  u32 *ignore = NULL;
  map_ip4_reass_lock ();
  map_ip4_reass_t *r =
    map_ip4_reass_get (ip4->src_address.as_u32, ip4->dst_address.as_u32,
                       ip4->fragment_id,
                       (ip4->protocol ==
                        IP_PROTOCOL_ICMP) ? IP_PROTOCOL_ICMP6 : ip4->protocol,
                       &ignore);
  i32 ret = r ? r->port : -1;
  map_ip4_reass_unlock ();
  return ret;
}

typedef struct
{
  map_domain_t *d;
  u16 id;
} icmp_to_icmp6_ctx_t;

static int
ip4_to_ip6_set_icmp_cb (ip4_header_t * ip4, ip6_header_t * ip6, void *arg)
{
  icmp_to_icmp6_ctx_t *ctx = arg;
  map_main_t *mm = &map_main;

  if (mm->is_ce)
    {
      ip6->src_address.as_u64[0] =
        map_get_pfx_net (ctx->d, ip4->src_address.as_u32, ctx->id);
      ip6->src_address.as_u64[1] =
        map_get_sfx_net (ctx->d, ip4->src_address.as_u32, ctx->id);
      ip4_map_t_embedded_address (ctx->d, &ip6->dst_address,
                                  &ip4->dst_address);
    }
  else
    {
      ip4_map_t_embedded_address (ctx->d, &ip6->src_address,
                                  &ip4->src_address);
      ip6->dst_address.as_u64[0] =
        map_get_pfx_net (ctx->d, ip4->dst_address.as_u32, ctx->id);
      ip6->dst_address.as_u64[1] =
        map_get_sfx_net (ctx->d, ip4->dst_address.as_u32, ctx->id);
    }

  return 0;
}

static int
ip4_to_ip6_set_inner_icmp_cb (ip4_header_t * ip4, ip6_header_t * ip6,
                              void *arg)
{
  icmp_to_icmp6_ctx_t *ctx = arg;
  map_main_t *mm = &map_main;

  if (mm->is_ce)
    {
      //Note that the destination address is within the domain
      //while the source address is the one outside the domain
      ip4_map_t_embedded_address (ctx->d, &ip6->src_address,
                                  &ip4->src_address);
      ip6->dst_address.as_u64[0] =
        map_get_pfx_net (ctx->d, ip4->dst_address.as_u32, ctx->id);
      ip6->dst_address.as_u64[1] =
        map_get_sfx_net (ctx->d, ip4->dst_address.as_u32, ctx->id);
    }
  else
    {
      //Note that the source address is within the domain
      //while the destination address is the one outside the domain
      ip4_map_t_embedded_address (ctx->d, &ip6->dst_address,
                                  &ip4->dst_address);
      ip6->src_address.as_u64[0] =
        map_get_pfx_net (ctx->d, ip4->src_address.as_u32, ctx->id);
      ip6->src_address.as_u64[1] =
        map_get_sfx_net (ctx->d, ip4->src_address.as_u32, ctx->id);
    }

  return 0;
}

static uword
ip4_map_t_icmp (vlib_main_t * vm,
                vlib_node_runtime_t * node, vlib_frame_t * frame)
{
  u32 n_left_from, *from, next_index, *to_next, n_left_to_next;
  vlib_node_runtime_t *error_node =
    vlib_node_get_runtime (vm, ip4_map_t_icmp_node.index);
  from = vlib_frame_vector_args (frame);
  n_left_from = frame->n_vectors;
  next_index = node->cached_next_index;
  vlib_combined_counter_main_t *cm = map_main.domain_counters;
  u32 thread_index = vm->thread_index;

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

      while (n_left_from > 0 && n_left_to_next > 0)
        {
          u32 pi0;
          vlib_buffer_t *p0;
          ip4_mapt_icmp_next_t next0;
          u8 error0;
          map_domain_t *d0;
          u16 len0;
          icmp_to_icmp6_ctx_t ctx0;
          ip4_header_t *ip40;
          icmp46_header_t *icmp0;

          next0 = IP4_MAPT_ICMP_NEXT_IP6_LOOKUP;
          pi0 = to_next[0] = from[0];
          from += 1;
          n_left_from -= 1;
          to_next += 1;
          n_left_to_next -= 1;
          error0 = MAP_ERROR_NONE;

          p0 = vlib_get_buffer (vm, pi0);
          vlib_buffer_advance (p0, sizeof (ip4_mapt_pseudo_header_t));  //The pseudo-header is not used
          len0 =
            clib_net_to_host_u16 (((ip4_header_t *)
                                   vlib_buffer_get_current (p0))->length);
          d0 =
            pool_elt_at_index (map_main.domains,
                               vnet_buffer (p0)->map_t.map_domain_index);

          ip40 = vlib_buffer_get_current (p0);
          icmp0 = (icmp46_header_t *) (ip40 + 1);

          ctx0.id = ip4_get_port (ip40, icmp0->type == ICMP6_echo_request);
          ctx0.d = d0;
          if (ctx0.id == 0)
            {
              // In case of 1:1 mapping, we don't care about the port
              if (!(d0->ea_bits_len == 0 && d0->rules))
                {
                  error0 = MAP_ERROR_ICMP;
                  goto err0;
                }
            }

          if (icmp_to_icmp6
              (p0, ip4_to_ip6_set_icmp_cb, &ctx0,
               ip4_to_ip6_set_inner_icmp_cb, &ctx0))
            {
              error0 = MAP_ERROR_ICMP;
              goto err0;
            }

          if (vnet_buffer (p0)->map_t.mtu < p0->current_length)
            {
              vnet_buffer (p0)->ip_frag.mtu = vnet_buffer (p0)->map_t.mtu;
              vnet_buffer (p0)->ip_frag.next_index = IP6_FRAG_NEXT_IP6_LOOKUP;
              next0 = IP4_MAPT_ICMP_NEXT_IP6_FRAG;
            }
        err0:
          if (PREDICT_TRUE (error0 == MAP_ERROR_NONE))
            {
              vlib_increment_combined_counter (cm + MAP_DOMAIN_COUNTER_TX,
                                               thread_index,
                                               vnet_buffer (p0)->
                                               map_t.map_domain_index, 1,
                                               len0);
            }
          else
            {
              next0 = IP4_MAPT_ICMP_NEXT_DROP;
            }
          p0->error = error_node->errors[error0];
          vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
                                           to_next, n_left_to_next, pi0,
                                           next0);
        }
      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
    }
  return frame->n_vectors;
}

static int
ip4_to_ip6_set_cb (ip4_header_t * ip4, ip6_header_t * ip6, void *ctx)
{
  ip4_mapt_pseudo_header_t *pheader = ctx;

  ip6->dst_address.as_u64[0] = pheader->daddr.as_u64[0];
  ip6->dst_address.as_u64[1] = pheader->daddr.as_u64[1];
  ip6->src_address.as_u64[0] = pheader->saddr.as_u64[0];
  ip6->src_address.as_u64[1] = pheader->saddr.as_u64[1];

  return 0;
}

static uword
ip4_map_t_fragmented (vlib_main_t * vm,
                      vlib_node_runtime_t * node, vlib_frame_t * frame)
{
  u32 n_left_from, *from, next_index, *to_next, n_left_to_next;
  from = vlib_frame_vector_args (frame);
  n_left_from = frame->n_vectors;
  next_index = node->cached_next_index;
  vlib_node_runtime_t *error_node =
    vlib_node_get_runtime (vm, ip4_map_t_fragmented_node.index);

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

      while (n_left_from > 0 && n_left_to_next > 0)
        {
          u32 pi0;
          vlib_buffer_t *p0;
          ip4_mapt_pseudo_header_t *pheader0;
          ip4_mapt_fragmented_next_t next0;

          next0 = IP4_MAPT_FRAGMENTED_NEXT_IP6_LOOKUP;
          pi0 = to_next[0] = from[0];
          from += 1;
          n_left_from -= 1;
          to_next += 1;
          n_left_to_next -= 1;

          p0 = vlib_get_buffer (vm, pi0);

          //Accessing pseudo header
          pheader0 = vlib_buffer_get_current (p0);
          vlib_buffer_advance (p0, sizeof (*pheader0));

          if (ip4_to_ip6_fragmented (p0, ip4_to_ip6_set_cb, pheader0))
            {
              p0->error = error_node->errors[MAP_ERROR_FRAGMENT_DROPPED];
              next0 = IP4_MAPT_FRAGMENTED_NEXT_DROP;
            }
          else
            {
              if (vnet_buffer (p0)->map_t.mtu < p0->current_length)
                {
                  vnet_buffer (p0)->ip_frag.mtu = vnet_buffer (p0)->map_t.mtu;
                  vnet_buffer (p0)->ip_frag.next_index =
                    IP6_FRAG_NEXT_IP6_LOOKUP;
                  next0 = IP4_MAPT_FRAGMENTED_NEXT_IP6_FRAG;
                }
            }

          vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
                                           to_next, n_left_to_next, pi0,
                                           next0);
        }
      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
    }
  return frame->n_vectors;
}

static uword
ip4_map_t_tcp_udp (vlib_main_t * vm,
                   vlib_node_runtime_t * node, vlib_frame_t * frame)
{
  u32 n_left_from, *from, next_index, *to_next, n_left_to_next;
  from = vlib_frame_vector_args (frame);
  n_left_from = frame->n_vectors;
  next_index = node->cached_next_index;
  vlib_node_runtime_t *error_node =
    vlib_node_get_runtime (vm, ip4_map_t_tcp_udp_node.index);


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

#ifdef IP4_MAP_T_DUAL_LOOP
      while (n_left_from >= 4 && n_left_to_next >= 2)
        {
          u32 pi0, pi1;
          vlib_buffer_t *p0, *p1;
          ip4_mapt_pseudo_header_t *pheader0, *pheader1;
          ip4_mapt_tcp_udp_next_t next0, next1;

          pi0 = to_next[0] = from[0];
          pi1 = to_next[1] = from[1];
          from += 2;
          n_left_from -= 2;
          to_next += 2;
          n_left_to_next -= 2;

          next0 = IP4_MAPT_TCP_UDP_NEXT_IP6_LOOKUP;
          next1 = IP4_MAPT_TCP_UDP_NEXT_IP6_LOOKUP;
          p0 = vlib_get_buffer (vm, pi0);
          p1 = vlib_get_buffer (vm, pi1);

          //Accessing pseudo header
          pheader0 = vlib_buffer_get_current (p0);
          pheader1 = vlib_buffer_get_current (p1);
          vlib_buffer_advance (p0, sizeof (*pheader0));
          vlib_buffer_advance (p1, sizeof (*pheader1));

          if (ip4_to_ip6_tcp_udp (p0, ip4_to_ip6_set_cb, pheader0))
            {
              p0->error = error_node->errors[MAP_ERROR_UNKNOWN];
              next0 = IP4_MAPT_TCP_UDP_NEXT_DROP;
            }
          else
            {
              if (vnet_buffer (p0)->map_t.mtu < p0->current_length)
                {
                  //Send to fragmentation node if necessary
                  vnet_buffer (p0)->ip_frag.mtu = vnet_buffer (p0)->map_t.mtu;
                  vnet_buffer (p0)->ip_frag.next_index =
                    IP6_FRAG_NEXT_IP6_LOOKUP;
                  next0 = IP4_MAPT_TCP_UDP_NEXT_IP6_FRAG;
                }
            }

          if (ip4_to_ip6_tcp_udp (p1, ip4_to_ip6_set_cb, pheader1))
            {
              p1->error = error_node->errors[MAP_ERROR_UNKNOWN];
              next1 = IP4_MAPT_TCP_UDP_NEXT_DROP;
            }
          else
            {
              if (vnet_buffer (p1)->map_t.mtu < p1->current_length)
                {
                  //Send to fragmentation node if necessary
                  vnet_buffer (p1)->ip_frag.mtu = vnet_buffer (p1)->map_t.mtu;
                  vnet_buffer (p1)->ip_frag.next_index =
                    IP6_FRAG_NEXT_IP6_LOOKUP;
                  next1 = IP4_MAPT_TCP_UDP_NEXT_IP6_FRAG;
                }
            }

          vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
                                           to_next, n_left_to_next, pi0, pi1,
                                           next0, next1);
        }
#endif

      while (n_left_from > 0 && n_left_to_next > 0)
        {
          u32 pi0;
          vlib_buffer_t *p0;
          ip4_mapt_pseudo_header_t *pheader0;
          ip4_mapt_tcp_udp_next_t next0;

          pi0 = to_next[0] = from[0];
          from += 1;
          n_left_from -= 1;
          to_next += 1;
          n_left_to_next -= 1;

          next0 = IP4_MAPT_TCP_UDP_NEXT_IP6_LOOKUP;
          p0 = vlib_get_buffer (vm, pi0);

          //Accessing pseudo header
          pheader0 = vlib_buffer_get_current (p0);
          vlib_buffer_advance (p0, sizeof (*pheader0));

          if (ip4_to_ip6_tcp_udp (p0, ip4_to_ip6_set_cb, pheader0))
            {
              p0->error = error_node->errors[MAP_ERROR_UNKNOWN];
              next0 = IP4_MAPT_TCP_UDP_NEXT_DROP;
            }
          else
            {
              if (vnet_buffer (p0)->map_t.mtu < p0->current_length)
                {
                  //Send to fragmentation node if necessary
                  vnet_buffer (p0)->ip_frag.mtu = vnet_buffer (p0)->map_t.mtu;
                  vnet_buffer (p0)->ip_frag.next_index =
                    IP6_FRAG_NEXT_IP6_LOOKUP;
                  next0 = IP4_MAPT_TCP_UDP_NEXT_IP6_FRAG;
                }
            }
          vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
                                           to_next, n_left_to_next, pi0,
                                           next0);
        }
      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
    }

  return frame->n_vectors;
}

static_always_inline void
ip4_map_t_classify (vlib_buffer_t * p0, map_domain_t * d0,
                    ip4_header_t * ip40, u16 ip4_len0, i32 * dst_port0,
                    u8 * error0, ip4_mapt_next_t * next0)
{
  map_main_t *mm = &map_main;
  u32 port_offset;

  if (mm->is_ce)
    port_offset = 0;
  else
    port_offset = 2;

  if (PREDICT_FALSE (ip4_get_fragment_offset (ip40)))
    {
      *next0 = IP4_MAPT_NEXT_MAPT_FRAGMENTED;
      if (d0->ea_bits_len == 0 && d0->rules)
        {
          *dst_port0 = 0;
        }
      else
        {
          *dst_port0 = ip4_map_fragment_get_port (ip40);
          *error0 = (*dst_port0 == -1) ? MAP_ERROR_FRAGMENT_MEMORY : *error0;
        }
    }
  else if (PREDICT_TRUE (ip40->protocol == IP_PROTOCOL_TCP))
    {
      vnet_buffer (p0)->map_t.checksum_offset = 36;
      *next0 = IP4_MAPT_NEXT_MAPT_TCP_UDP;
      *error0 = ip4_len0 < 40 ? MAP_ERROR_MALFORMED : *error0;
      *dst_port0 =
        (i32) * ((u16 *) u8_ptr_add (ip40, sizeof (*ip40) + port_offset));
    }
  else if (PREDICT_TRUE (ip40->protocol == IP_PROTOCOL_UDP))
    {
      vnet_buffer (p0)->map_t.checksum_offset = 26;
      *next0 = IP4_MAPT_NEXT_MAPT_TCP_UDP;
      *error0 = ip4_len0 < 28 ? MAP_ERROR_MALFORMED : *error0;
      *dst_port0 =
        (i32) * ((u16 *) u8_ptr_add (ip40, sizeof (*ip40) + port_offset));
    }
  else if (ip40->protocol == IP_PROTOCOL_ICMP)
    {
      *next0 = IP4_MAPT_NEXT_MAPT_ICMP;
      if (d0->ea_bits_len == 0 && d0->rules)
        *dst_port0 = 0;
      else if (((icmp46_header_t *) u8_ptr_add (ip40, sizeof (*ip40)))->code
               == ICMP4_echo_reply
               || ((icmp46_header_t *)
                   u8_ptr_add (ip40,
                               sizeof (*ip40)))->code == ICMP4_echo_request)
        *dst_port0 = (i32) * ((u16 *) u8_ptr_add (ip40, sizeof (*ip40) + 6));
    }
  else
    {
      *error0 = MAP_ERROR_BAD_PROTOCOL;
    }
}

static uword
ip4_map_t (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
{
  u32 n_left_from, *from, next_index, *to_next, n_left_to_next;
  vlib_node_runtime_t *error_node =
    vlib_node_get_runtime (vm, ip4_map_t_node.index);
  from = vlib_frame_vector_args (frame);
  n_left_from = frame->n_vectors;
  next_index = node->cached_next_index;
  map_main_t *mm = &map_main;
  vlib_combined_counter_main_t *cm = map_main.domain_counters;
  u32 thread_index = vm->thread_index;

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

#ifdef IP4_MAP_T_DUAL_LOOP
      while (n_left_from >= 4 && n_left_to_next >= 2)
        {
          u32 pi0, pi1;
          vlib_buffer_t *p0, *p1;
          ip4_header_t *ip40, *ip41;
          map_domain_t *d0, *d1;
          ip4_mapt_next_t next0 = 0, next1 = 0;
          u16 ip4_len0, ip4_len1;
          u8 error0, error1;
          i32 map_port0, map_port1;
          ip4_mapt_pseudo_header_t *pheader0, *pheader1;

          pi0 = to_next[0] = from[0];
          pi1 = to_next[1] = from[1];
          from += 2;
          n_left_from -= 2;
          to_next += 2;
          n_left_to_next -= 2;
          error0 = MAP_ERROR_NONE;
          error1 = MAP_ERROR_NONE;

          p0 = vlib_get_buffer (vm, pi0);
          p1 = vlib_get_buffer (vm, pi1);
          ip40 = vlib_buffer_get_current (p0);
          ip41 = vlib_buffer_get_current (p1);
          ip4_len0 = clib_host_to_net_u16 (ip40->length);
          ip4_len1 = clib_host_to_net_u16 (ip41->length);

          if (PREDICT_FALSE (p0->current_length < ip4_len0 ||
                             ip40->ip_version_and_header_length != 0x45))
            {
              error0 = MAP_ERROR_UNKNOWN;
              next0 = IP4_MAPT_NEXT_DROP;
            }

          if (PREDICT_FALSE (p1->current_length < ip4_len1 ||
                             ip41->ip_version_and_header_length != 0x45))
            {
              error1 = MAP_ERROR_UNKNOWN;
              next1 = IP4_MAPT_NEXT_DROP;
            }

          vnet_buffer (p0)->map_t.map_domain_index =
            vnet_buffer (p0)->ip.adj_index[VLIB_TX];
          d0 = ip4_map_get_domain (vnet_buffer (p0)->map_t.map_domain_index);
          vnet_buffer (p1)->map_t.map_domain_index =
            vnet_buffer (p1)->ip.adj_index[VLIB_TX];
          d1 = ip4_map_get_domain (vnet_buffer (p1)->map_t.map_domain_index);

          vnet_buffer (p0)->map_t.mtu = d0->mtu ? d0->mtu : ~0;
          vnet_buffer (p1)->map_t.mtu = d1->mtu ? d1->mtu : ~0;

          map_port0 = -1;
          map_port1 = -1;

          ip4_map_t_classify (p0, d0, ip40, ip4_len0, &map_port0, &error0,
                              &next0);
          ip4_map_t_classify (p1, d1, ip41, ip4_len1, &map_port1, &error1,
                              &next1);

          //Add MAP-T pseudo header in front of the packet
          vlib_buffer_advance (p0, -sizeof (*pheader0));
          vlib_buffer_advance (p1, -sizeof (*pheader1));
          pheader0 = vlib_buffer_get_current (p0);
          pheader1 = vlib_buffer_get_current (p1);

          //Save addresses within the packet
          if (mm->is_ce)
            {
              ip4_map_t_embedded_address (d0, &pheader0->daddr,
                                          &ip40->dst_address);
              ip4_map_t_embedded_address (d1, &pheader1->daddr,
                                          &ip41->dst_address);
              pheader0->saddr.as_u64[0] =
                map_get_pfx_net (d0, ip40->src_address.as_u32,
                                 (u16) map_port0);
              pheader0->saddr.as_u64[1] =
                map_get_sfx_net (d0, ip40->src_address.as_u32,
                                 (u16) map_port0);
              pheader1->saddr.as_u64[0] =
                map_get_pfx_net (d1, ip41->src_address.as_u32,
                                 (u16) map_port1);
              pheader1->saddr.as_u64[1] =
                map_get_sfx_net (d1, ip41->src_address.as_u32,
                                 (u16) map_port1);
            }
          else
            {
              ip4_map_t_embedded_address (d0, &pheader0->saddr,
                                          &ip40->src_address);
              ip4_map_t_embedded_address (d1, &pheader1->saddr,
                                          &ip41->src_address);
              pheader0->daddr.as_u64[0] =
                map_get_pfx_net (d0, ip40->dst_address.as_u32,
                                 (u16) map_port0);
              pheader0->daddr.as_u64[1] =
                map_get_sfx_net (d0, ip40->dst_address.as_u32,
                                 (u16) map_port0);
              pheader1->daddr.as_u64[0] =
                map_get_pfx_net (d1, ip41->dst_address.as_u32,
                                 (u16) map_port1);
              pheader1->daddr.as_u64[1] =
                map_get_sfx_net (d1, ip41->dst_address.as_u32,
                                 (u16) map_port1);
            }

          if (PREDICT_FALSE
              (ip4_is_first_fragment (ip40) && (map_port0 != -1)
               && (d0->ea_bits_len != 0 || !d0->rules)
               && ip4_map_fragment_cache (ip40, map_port0)))
            {
              error0 = MAP_ERROR_FRAGMENT_MEMORY;
            }

          if (PREDICT_FALSE
              (ip4_is_first_fragment (ip41) && (map_port1 != -1)
               && (d1->ea_bits_len != 0 || !d1->rules)
               && ip4_map_fragment_cache (ip41, map_port1)))
            {
              error1 = MAP_ERROR_FRAGMENT_MEMORY;
            }

          if (PREDICT_TRUE
              (error0 == MAP_ERROR_NONE && next0 != IP4_MAPT_NEXT_MAPT_ICMP))
            {
              vlib_increment_combined_counter (cm + MAP_DOMAIN_COUNTER_TX,
                                               thread_index,
                                               vnet_buffer (p0)->
                                               map_t.map_domain_index, 1,
                                               clib_net_to_host_u16
                                               (ip40->length));
            }

          if (PREDICT_TRUE
              (error1 == MAP_ERROR_NONE && next1 != IP4_MAPT_NEXT_MAPT_ICMP))
            {
              vlib_increment_combined_counter (cm + MAP_DOMAIN_COUNTER_TX,
                                               thread_index,
                                               vnet_buffer (p1)->
                                               map_t.map_domain_index, 1,
                                               clib_net_to_host_u16
                                               (ip41->length));
            }

          next0 = (error0 != MAP_ERROR_NONE) ? IP4_MAPT_NEXT_DROP : next0;
          next1 = (error1 != MAP_ERROR_NONE) ? IP4_MAPT_NEXT_DROP : next1;
          p0->error = error_node->errors[error0];
          p1->error = error_node->errors[error1];
          vlib_validate_buffer_enqueue_x2 (vm, node, next_index, to_next,
                                           n_left_to_next, pi0, pi1, next0,
                                           next1);
        }
#endif

      while (n_left_from > 0 && n_left_to_next > 0)
        {
          u32 pi0;
          vlib_buffer_t *p0;
          ip4_header_t *ip40;
          map_domain_t *d0;
          ip4_mapt_next_t next0;
          u16 ip4_len0;
          u8 error0;
          i32 map_port0;
          ip4_mapt_pseudo_header_t *pheader0;

          pi0 = to_next[0] = from[0];
          from += 1;
          n_left_from -= 1;
          to_next += 1;
          n_left_to_next -= 1;
          error0 = MAP_ERROR_NONE;

          p0 = vlib_get_buffer (vm, pi0);
          ip40 = vlib_buffer_get_current (p0);
          ip4_len0 = clib_host_to_net_u16 (ip40->length);
          if (PREDICT_FALSE (p0->current_length < ip4_len0 ||
                             ip40->ip_version_and_header_length != 0x45))
            {
              error0 = MAP_ERROR_UNKNOWN;
              next0 = IP4_MAPT_NEXT_DROP;
            }

          vnet_buffer (p0)->map_t.map_domain_index =
            vnet_buffer (p0)->ip.adj_index[VLIB_TX];
          d0 = ip4_map_get_domain (vnet_buffer (p0)->map_t.map_domain_index);

          vnet_buffer (p0)->map_t.mtu = d0->mtu ? d0->mtu : ~0;

          map_port0 = -1;
          ip4_map_t_classify (p0, d0, ip40, ip4_len0, &map_port0, &error0,
                              &next0);

          /* Verify that port is not among the well-known ports */
          if ((d0->psid_length > 0 && d0->psid_offset > 0)
              && (clib_net_to_host_u16 (map_port0) <
                  (0x1 << (16 - d0->psid_offset))))
            {
              error0 = MAP_ERROR_SEC_CHECK;
            }

          //Add MAP-T pseudo header in front of the packet
          vlib_buffer_advance (p0, -sizeof (*pheader0));
          pheader0 = vlib_buffer_get_current (p0);

          //Save addresses within the packet
          if (mm->is_ce)
            {
              ip4_map_t_embedded_address (d0, &pheader0->daddr,
                                          &ip40->dst_address);
              pheader0->saddr.as_u64[0] =
                map_get_pfx_net (d0, ip40->src_address.as_u32,
                                 (u16) map_port0);
              pheader0->saddr.as_u64[1] =
                map_get_sfx_net (d0, ip40->src_address.as_u32,
                                 (u16) map_port0);
            }
          else
            {
              ip4_map_t_embedded_address (d0, &pheader0->saddr,
                                          &ip40->src_address);
              pheader0->daddr.as_u64[0] =
                map_get_pfx_net (d0, ip40->dst_address.as_u32,
                                 (u16) map_port0);
              pheader0->daddr.as_u64[1] =
                map_get_sfx_net (d0, ip40->dst_address.as_u32,
                                 (u16) map_port0);
            }

          //It is important to cache at this stage because the result might be necessary
          //for packets within the same vector.
          //Actually, this approach even provides some limited out-of-order fragments support
          if (PREDICT_FALSE
              (ip4_is_first_fragment (ip40) && (map_port0 != -1)
               && (d0->ea_bits_len != 0 || !d0->rules)
               && ip4_map_fragment_cache (ip40, map_port0)))
            {
              error0 = MAP_ERROR_UNKNOWN;
            }

          if (PREDICT_TRUE
              (error0 == MAP_ERROR_NONE && next0 != IP4_MAPT_NEXT_MAPT_ICMP))
            {
              vlib_increment_combined_counter (cm + MAP_DOMAIN_COUNTER_TX,
                                               thread_index,
                                               vnet_buffer (p0)->
                                               map_t.map_domain_index, 1,
                                               clib_net_to_host_u16
                                               (ip40->length));
            }

          next0 = (error0 != MAP_ERROR_NONE) ? IP4_MAPT_NEXT_DROP : next0;
          p0->error = error_node->errors[error0];
          vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
                                           to_next, n_left_to_next, pi0,
                                           next0);
        }
      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
    }
  return frame->n_vectors;
}

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

/* *INDENT-OFF* */
VLIB_REGISTER_NODE(ip4_map_t_fragmented_node) = {
  .function = ip4_map_t_fragmented,
  .name = "ip4-map-t-fragmented",
  .vector_size = sizeof(u32),
  .format_trace = format_map_trace,
  .type = VLIB_NODE_TYPE_INTERNAL,

  .n_errors = MAP_N_ERROR,
  .error_strings = map_t_error_strings,

  .n_next_nodes = IP4_MAPT_FRAGMENTED_N_NEXT,
  .next_nodes = {
      [IP4_MAPT_FRAGMENTED_NEXT_IP6_LOOKUP] = "ip6-lookup",
      [IP4_MAPT_FRAGMENTED_NEXT_IP6_FRAG] = IP6_FRAG_NODE_NAME,
      [IP4_MAPT_FRAGMENTED_NEXT_DROP] = "error-drop",
  },
};
/* *INDENT-ON* */

/* *INDENT-OFF* */
VLIB_REGISTER_NODE(ip4_map_t_icmp_node) = {
  .function = ip4_map_t_icmp,
  .name = "ip4-map-t-icmp",
  .vector_size = sizeof(u32),
  .format_trace = format_map_trace,
  .type = VLIB_NODE_TYPE_INTERNAL,

  .n_errors = MAP_N_ERROR,
  .error_strings = map_t_error_strings,

  .n_next_nodes = IP4_MAPT_ICMP_N_NEXT,
  .next_nodes = {
      [IP4_MAPT_ICMP_NEXT_IP6_LOOKUP] = "ip6-lookup",
      [IP4_MAPT_ICMP_NEXT_IP6_FRAG] = IP6_FRAG_NODE_NAME,
      [IP4_MAPT_ICMP_NEXT_DROP] = "error-drop",
  },
};
/* *INDENT-ON* */

/* *INDENT-OFF* */
VLIB_REGISTER_NODE(ip4_map_t_tcp_udp_node) = {
  .function = ip4_map_t_tcp_udp,
  .name = "ip4-map-t-tcp-udp",
  .vector_size = sizeof(u32),
  .format_trace = format_map_trace,
  .type = VLIB_NODE_TYPE_INTERNAL,

  .n_errors = MAP_N_ERROR,
  .error_strings = map_t_error_strings,

  .n_next_nodes = IP4_MAPT_TCP_UDP_N_NEXT,
  .next_nodes = {
      [IP4_MAPT_TCP_UDP_NEXT_IP6_LOOKUP] = "ip6-lookup",
      [IP4_MAPT_TCP_UDP_NEXT_IP6_FRAG] = IP6_FRAG_NODE_NAME,
      [IP4_MAPT_TCP_UDP_NEXT_DROP] = "error-drop",
  },
};
/* *INDENT-ON* */

/* *INDENT-OFF* */
VLIB_REGISTER_NODE(ip4_map_t_node) = {
  .function = ip4_map_t,
  .name = "ip4-map-t",
  .vector_size = sizeof(u32),
  .format_trace = format_map_trace,
  .type = VLIB_NODE_TYPE_INTERNAL,

  .n_errors = MAP_N_ERROR,
  .error_strings = map_t_error_strings,

  .n_next_nodes = IP4_MAPT_N_NEXT,
  .next_nodes = {
      [IP4_MAPT_NEXT_MAPT_TCP_UDP] = "ip4-map-t-tcp-udp",
      [IP4_MAPT_NEXT_MAPT_ICMP] = "ip4-map-t-icmp",
      [IP4_MAPT_NEXT_MAPT_FRAGMENTED] = "ip4-map-t-fragmented",
      [IP4_MAPT_NEXT_DROP] = "error-drop",
  },
};
/* *INDENT-ON* */

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