/*
 * Copyright (c) 2001, 2002 Swedish Institute of Computer Science.
 * All rights reserved. 
 * 
 * Redistribution and use in source and binary forms, with or without modification, 
 * are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission. 
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
 * OF SUCH DAMAGE.
 *
 * This file is part of the lwIP TCP/IP stack.
 * 
 * Author: Adam Dunkels <adam@sics.se>
 *
 */
#ifndef __LWIP_ICMP_H__
#define __LWIP_ICMP_H__

#include "lwip/arch.h"

#include "lwip/opt.h"
#include "lwip/pbuf.h"

#include "lwip/netif.h"

#define ICMP_ER 0      /* echo reply */
#define ICMP_DUR 3     /* destination unreachable */
#define ICMP_SQ 4      /* source quench */
#define ICMP_RD 5      /* redirect */
#define ICMP_ECHO 8    /* echo */
#define ICMP_TE 11     /* time exceeded */
#define ICMP_PP 12     /* parameter problem */
#define ICMP_TS 13     /* timestamp */
#define ICMP_TSR 14    /* timestamp reply */
#define ICMP_IRQ 15    /* information request */
#define ICMP_IR 16     /* information reply */

enum icmp_dur_type {
  ICMP_DUR_NET = 0,    /* net unreachable */
  ICMP_DUR_HOST = 1,   /* host unreachable */
  ICMP_DUR_PROTO = 2,  /* protocol unreachable */
  ICMP_DUR_PORT = 3,   /* port unreachable */
  ICMP_DUR_FRAG = 4,   /* fragmentation needed and DF set */
  ICMP_DUR_SR = 5      /* source route failed */
};

enum icmp_te_type {
  ICMP_TE_TTL = 0,     /* time to live exceeded in transit */
  ICMP_TE_FRAG = 1     /* fragment reassembly time exceeded */
};

void icmp_input(struct pbuf *p, struct netif *inp);

void icmp_dest_unreach(struct pbuf *p, enum icmp_dur_type t);
void icmp_time_exceeded(struct pbuf *p, enum icmp_te_type t);

PACK_STRUCT_BEGIN
struct icmp_echo_hdr {
  PACK_STRUCT_FIELD(u16_t _type_code);
  PACK_STRUCT_FIELD(u16_t chksum);
  PACK_STRUCT_FIELD(u16_t id);
  PACK_STRUCT_FIELD(u16_t seqno);
} PACK_STRUCT_STRUCT;
PACK_STRUCT_END

PACK_STRUCT_BEGIN
struct icmp_dur_hdr {
  PACK_STRUCT_FIELD(u16_t _type_code);
  PACK_STRUCT_FIELD(u16_t chksum);
  PACK_STRUCT_FIELD(u32_t unused);
} PACK_STRUCT_STRUCT;
PACK_STRUCT_END

PACK_STRUCT_BEGIN
struct icmp_te_hdr {
  PACK_STRUCT_FIELD(u16_t _type_code);
  PACK_STRUCT_FIELD(u16_t chksum);
  PACK_STRUCT_FIELD(u32_t unused);
} PACK_STRUCT_STRUCT;
PACK_STRUCT_END

#define ICMPH_TYPE(hdr) (NTOHS((hdr)->_type_code) >> 8)
#define ICMPH_CODE(hdr) (NTOHS((hdr)->_type_code) & 0xff)

#define ICMPH_TYPE_SET(hdr, type) ((hdr)->_type_code = HTONS(ICMPH_CODE(hdr) | ((type) << 8)))
#define ICMPH_CODE_SET(hdr, code) ((hdr)->_type_code = HTONS((code) | (ICMPH_TYPE(hdr) << 8)))

#endif /* __LWIP_ICMP_H__ */