minix/lib/liblwip/dist/src/include/lwip/prot/etharp.h

   1 /**
   2  * @file
   3  * ARP protocol definitions
   4  */
   5
   6 /*
   7  * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
   8  * All rights reserved.
   9  *
  10  * Redistribution and use in source and binary forms, with or without modification,
  11  * are permitted provided that the following conditions are met:
  12  *
  13  * 1. Redistributions of source code must retain the above copyright notice,
  14  *    this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright notice,
  16  *    this list of conditions and the following disclaimer in the documentation
  17  *    and/or other materials provided with the distribution.
  18  * 3. The name of the author may not be used to endorse or promote products
  19  *    derived from this software without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
  22  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  23  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
  24  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  25  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
  26  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  29  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
  30  * OF SUCH DAMAGE.
  31  *
  32  * This file is part of the lwIP TCP/IP stack.
  33  *
  34  * Author: Adam Dunkels <adam@sics.se>
  35  *
  36  */
  37 #ifndef LWIP_HDR_PROT_ETHARP_H
  38 #define LWIP_HDR_PROT_ETHARP_H
  39
  40 #include "lwip/arch.h"
  41 #include "lwip/prot/ethernet.h"
  42
  43 #ifdef __cplusplus
  44 extern "C" {
  45 #endif
  46
  47 #ifndef ETHARP_HWADDR_LEN
  48 #define ETHARP_HWADDR_LEN     ETH_HWADDR_LEN
  49 #endif
  50
  51 /**
  52  * struct ip4_addr_wordaligned is used in the definition of the ARP packet format in
  53  * order to support compilers that don't have structure packing.
  54  */
  55 #ifdef PACK_STRUCT_USE_INCLUDES
  56 #  include "arch/bpstruct.h"
  57 #endif
  58 PACK_STRUCT_BEGIN
  59 struct ip4_addr_wordaligned {
  60   PACK_STRUCT_FIELD(u16_t addrw[2]);
  61 } PACK_STRUCT_STRUCT;
  62 PACK_STRUCT_END
  63 #ifdef PACK_STRUCT_USE_INCLUDES
  64 #  include "arch/epstruct.h"
  65 #endif
  66
  67 /** MEMCPY-like copying of IP addresses where addresses are known to be
  68  * 16-bit-aligned if the port is correctly configured (so a port could define
  69  * this to copying 2 u16_t's) - no NULL-pointer-checking needed. */
  70 #ifndef IPADDR_WORDALIGNED_COPY_TO_IP4_ADDR_T
  71 #define IPADDR_WORDALIGNED_COPY_TO_IP4_ADDR_T(dest, src) SMEMCPY(dest, src, sizeof(ip4_addr_t))
  72 #endif
  73
  74  /** MEMCPY-like copying of IP addresses where addresses are known to be
  75  * 16-bit-aligned if the port is correctly configured (so a port could define
  76  * this to copying 2 u16_t's) - no NULL-pointer-checking needed. */
  77 #ifndef IPADDR_WORDALIGNED_COPY_FROM_IP4_ADDR_T
  78 #define IPADDR_WORDALIGNED_COPY_FROM_IP4_ADDR_T(dest, src) SMEMCPY(dest, src, sizeof(ip4_addr_t))
  79 #endif
  80
  81 #ifdef PACK_STRUCT_USE_INCLUDES
  82 #  include "arch/bpstruct.h"
  83 #endif
  84 PACK_STRUCT_BEGIN
  85 /** the ARP message, see RFC 826 ("Packet format") */
  86 struct etharp_hdr {
  87   PACK_STRUCT_FIELD(u16_t hwtype);
  88   PACK_STRUCT_FIELD(u16_t proto);
  89   PACK_STRUCT_FLD_8(u8_t  hwlen);
  90   PACK_STRUCT_FLD_8(u8_t  protolen);
  91   PACK_STRUCT_FIELD(u16_t opcode);
  92   PACK_STRUCT_FLD_S(struct eth_addr shwaddr);
  93   PACK_STRUCT_FLD_S(struct ip4_addr_wordaligned sipaddr);
  94   PACK_STRUCT_FLD_S(struct eth_addr dhwaddr);
  95   PACK_STRUCT_FLD_S(struct ip4_addr_wordaligned dipaddr);
  96 } PACK_STRUCT_STRUCT;
  97 PACK_STRUCT_END
  98 #ifdef PACK_STRUCT_USE_INCLUDES
  99 #  include "arch/epstruct.h"
 100 #endif
 101
 102 #define SIZEOF_ETHARP_HDR 28
 103
 104 /* ARP hwtype values */
 105 enum etharp_hwtype {
 106   HWTYPE_ETHERNET = 1
 107   /* others not used */
 108 };
 109
 110 /* ARP message types (opcodes) */
 111 enum etharp_opcode {
 112   ARP_REQUEST = 1,
 113   ARP_REPLY   = 2
 114 };
 115
 116 #ifdef __cplusplus
 117 }
 118 #endif
 119
 120 #endif /* LWIP_HDR_PROT_ETHARP_H */