/*
 * Copyright (c) 2017-2019 Cisco and/or its affiliates.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef __HICN_FACE_UDP_H__
#define __HICN_FACE_UDP_H__

#include <vlib/vlib.h>
#include <vnet/vnet.h>
#include <vnet/ip/ip6_packet.h>
#include <vnet/udp/udp_packet.h>

#include "../face.h"

/**
 * @file
 * @brief UDP face
 *
 * This file containes the definition of UDP faces.
 * UDP faces encap and decap an hicn packet into a UDP tunnel.
 * Src and dst address in interest and data packets are not considered and
 * should be set to 0 (not checked in the forwarder).
 */

/* Pre-instantiated ip header to fast fill an newly encapsulated packet */
extern ip4_header_t ip4_header_skl;
extern ip6_header_t ip6_header_skl;

#define INVALID_UDP_DPO_INDEX ~0

/**
 * @brief UDP face representation. The following is stored in the data field of
 * an hicn_face_t object (see hicn_face.h). A UDP face is identifies by the
 * quadruplet (src addr, dst addr, src port, dst port).
 */
typedef struct hicn_face_udp_t_
{
  /**
   * The headers to paint, in packet painting order
   */
  union
  {
    struct
    {
      ip4_header_t ip;
      udp_header_t udp;
    } __attribute__ ((packed)) ip4;
    struct
    {
      ip6_header_t ip;
      udp_header_t udp;
    } __attribute__ ((packed)) ip6;
  } __attribute__ ((packed)) hdrs;
} hicn_face_udp_t;

/* Hast table mapping the udp key with the face id (dpoi_index pointing to and
   element in the face pool defined in hicn_face.h)*/
extern mhash_t hicn_face_udp_hashtb;

/**
 * @brief Hash table key.
 */
typedef struct hicn_face_udp_key_s
{
  ip46_address_t local_addr;
  ip46_address_t remote_addr;
  u16 local_port;
  u16 remote_port;
} hicn_face_udp_key_t;

/* DPO type for the udp face */
extern dpo_type_t hicn_face_udp_type;

/* VFT table for the udp face. Mainly used to format the face in the right way */
extern hicn_face_vft_t udp_vft;

/**
 * @brief Create the key object for the mhash. Fill in the key object with the
 * expected values.
 *
 * @param local_addr Local address of the UDP tunnel
 * @param remote_addr Remote address of the UDP tunnel
 * @param local_port Local port of the UDP tunnel
 * @param remote_port Remote port of the UDP tunnel
 * @param key Pointer to an allocated hic