/****************************************************************************
 * include/netinet/ip.h
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.  The
 * ASF licenses this file to you 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 __INCLUDE_NETINET_IP_H
#define __INCLUDE_NETINET_IP_H

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <sys/socket.h>
#include <netinet/in.h>

/****************************************************************************
 * Public Type Definitions
 ****************************************************************************/

#define IPVERSION 4     /* IP version number */
#define IPDEFTTL  64    /* default ttl, from RFC 1340 */

/* Values for the TOS field */

#define IPTOS_TOS_MASK    0x1e
#define IPTOS_TOS(tos)    ((tos) & IPTOS_TOS_MASK)
#define IPTOS_LOWDELAY    0x10
#define IPTOS_THROUGHPUT  0x08
#define IPTOS_RELIABILITY 0x04
#define IPTOS_MINCOST     0x02

#define IPTOS_PREC_MASK            0xe0
#define IPTOS_PREC(tos)            ((tos) & IPTOS_PREC_MASK)
#define IPTOS_PREC_NETCONTROL      0xe0
#define IPTOS_PREC_INTERNETCONTROL 0xc0
#define IPTOS_PREC_CRITIC_ECP      0xa0
#define IPTOS_PREC_FLASHOVERRIDE   0x80
#define IPTOS_PREC_FLASH           0x60
#define IPTOS_PREC_IMMEDIATE       0x40
#define IPTOS_PREC_PRIORITY        0x20
#define IPTOS_PREC_ROUTINE         0x00

struct iphdr
{
#if __BYTE_ORDER == __LITTLE_ENDIAN
  uint8_t ihl:4;
  uint8_t version:4;
#elif __BYTE_ORDER == __BIG_ENDIAN
  uint8_t version:4;
  uint8_t ihl:4;
#else
# error "unknown endian"
#endif
  uint8_t tos;
  uint16_t tot_len;
  uint16_t id;
  uint16_t frag_off;
  uint8_t ttl;
  uint8_t protocol;
  uint16_t check;
  uint32_t saddr;
  uint32_t daddr;

  /* The options start here. */
};

/* Structure of an internet header, naked of options. */

struct ip
{
#if __BYTE_ORDER == __LITTLE_ENDIAN
  uint8_t ip_hl:4;           /* Header length */
  uint8_t ip_v:4;            /* Version */
#endif
#if __BYTE_ORDER == __BIG_ENDIAN
  uint8_t ip_v:4;            /* Version */
  uint8_t ip_hl:4;           /* Header length */
#endif
  uint8_t ip_tos;            /* Type of service */
  uint16_t ip_len;           /* Total length */
  uint16_t ip_id;            /* Identification */
  uint16_t ip_off;           /* Fragment offset field */
#define IP_RF 0x8000         /* Reserved fragment flag */
#define IP_DF 0x4000         /* Dont fragment flag */
#define IP_MF 0x2000         /* More fragments flag */
#define IP_OFFMASK 0x1fff    /* Mask for fragmenting bits */
  uint8_t ip_ttl;            /* Time to live */
  uint8_t ip_p;              /* Protocol */
  uint16_t ip_sum;           /* Checksum */
  struct in_addr ip_src;     /* Source address */
  struct in_addr ip_dst;     /* Destination address */
};

/****************************************************************************
 * Public Function Prototypes
 ****************************************************************************/

#endif /* __INCLUDE_NETINET_IP_H */