text: /*
   * Copyright (c) 2001-2004 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/opt.h"
  #include "lwip/pbuf.h"
  #include "lwip/ip_addr.h"
  #include "lwip/netif.h"
  
  #if LWIP_IPV6 && LWIP_ICMP6
  #include "lwip/icmp6.h"
  #endif
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  #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 */
  };
  
  #ifdef PACK_STRUCT_USE_INCLUDES
  #  include "arch/bpstruct.h"
  #endif
  /** This is the standard ICMP header only that the u32_t data
   *  is splitted to two u16_t like ICMP echo needs it.
   *  This header is also used for other ICMP types that do not
   *  use the data part.
   */
  PACK_STRUCT_BEGIN
  struct icmp_echo_hdr {
    PACK_STRUCT_FIELD(u8_t type);
    PACK_STRUCT_FIELD(u8_t 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
  #ifdef PACK_STRUCT_USE_INCLUDES
  #  include "arch/epstruct.h"
  #endif
  
  #define ICMPH_TYPE(hdr) ((hdr)->type)
  #define ICMPH_CODE(hdr) ((hdr)->code)
  
  /** Combines type and code to an u16_t */
  #define ICMPH_TYPE_SET(hdr, t) ((hdr)->type = (t))
  #define ICMPH_CODE_SET(hdr, c) ((hdr)->code = (c))
  
  
  #if LWIP_ICMP /* don't build if not configured for use in lwipopts.h */
  
  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);
  
  #endif /* LWIP_ICMP */
  
  #if (LWIP_IPV6 && LWIP_ICMP6)
  #if LWIP_ICMP
  #define icmp_port_unreach(isipv6, pbuf) ((isipv6) ? \
                                           icmp6_dest_unreach(pbuf, ICMP6_DUR_PORT) : \
                                           icmp_dest_unreach(pbuf, ICMP_DUR_PORT))
  #else /* LWIP_ICMP */
  #define icmp_port_unreach(isipv6, pbuf) icmp6_dest_unreach(pbuf, ICMP6_DUR_PORT)
  #endif /*LWIP_ICMP */
  #elif LWIP_ICMP
  #define icmp_port_unreach(isipv6, pbuf) icmp_dest_unreach(pbuf, ICMP_DUR_PORT)
  #else /* (LWIP_IPV6 && LWIP_ICMP6) || LWIP_ICMP*/
  #define icmp_port_unreach(isipv6, pbuf)
  #endif /* (LWIP_IPV6 && LWIP_ICMP6) || LWIP_ICMP*/
  
  #ifdef __cplusplus
  }
  #endif
  
  #endif /* __LWIP_ICMP_H__ */
  