icmp.h

这是我们的嵌入式作业 在嵌入式平台上开发的

/*
 * Copyright (c) 2001, 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. Neither the name of the Institute nor the names of its contributors 
 *    may be used to endorse or promote products derived from this software 
 *    without specific prior written permission. 
 *
 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``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 INSTITUTE OR CONTRIBUTORS 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 <[e-mail]>
 *
 * $Id: icmp.h,v 1.2 2002/03/04 10:47:56 adam Exp $
 */
#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);

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;



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;

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;

#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__ */