minix/lib/liblwip/dist/src/include/lwip/prot/ip4.h

   1 /**
   2  * @file
   3  * IPv4 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_IP4_H
  38 #define LWIP_HDR_PROT_IP4_H
  39
  40 #include "lwip/arch.h"
  41 #include "lwip/ip4_addr.h"
  42
  43 #ifdef __cplusplus
  44 extern "C" {
  45 #endif
  46
  47 /** This is the packed version of ip4_addr_t,
  48     used in network headers that are itself packed */
  49 #ifdef PACK_STRUCT_USE_INCLUDES
  50 #  include "arch/bpstruct.h"
  51 #endif
  52 PACK_STRUCT_BEGIN
  53 struct ip4_addr_packed {
  54   PACK_STRUCT_FIELD(u32_t addr);
  55 } PACK_STRUCT_STRUCT;
  56 PACK_STRUCT_END
  57 #ifdef PACK_STRUCT_USE_INCLUDES
  58 #  include "arch/epstruct.h"
  59 #endif
  60
  61 typedef struct ip4_addr_packed ip4_addr_p_t;
  62
  63 /* Size of the IPv4 header. Same as 'sizeof(struct ip_hdr)'. */
  64 #define IP_HLEN 20
  65
  66 #ifdef PACK_STRUCT_USE_INCLUDES
  67 #  include "arch/bpstruct.h"
  68 #endif
  69 PACK_STRUCT_BEGIN
  70 /* The IPv4 header */
  71 struct ip_hdr {
  72   /* version / header length */
  73   PACK_STRUCT_FLD_8(u8_t _v_hl);
  74   /* type of service */
  75   PACK_STRUCT_FLD_8(u8_t _tos);
  76   /* total length */
  77   PACK_STRUCT_FIELD(u16_t _len);
  78   /* identification */
  79   PACK_STRUCT_FIELD(u16_t _id);
  80   /* fragment offset field */
  81   PACK_STRUCT_FIELD(u16_t _offset);
  82 #define IP_RF 0x8000U        /* reserved fragment flag */
  83 #define IP_DF 0x4000U        /* don't fragment flag */
  84 #define IP_MF 0x2000U        /* more fragments flag */
  85 #define IP_OFFMASK 0x1fffU   /* mask for fragmenting bits */
  86   /* time to live */
  87   PACK_STRUCT_FLD_8(u8_t _ttl);
  88   /* protocol*/
  89   PACK_STRUCT_FLD_8(u8_t _proto);
  90   /* checksum */
  91   PACK_STRUCT_FIELD(u16_t _chksum);
  92   /* source and destination IP addresses */
  93   PACK_STRUCT_FLD_S(ip4_addr_p_t src);
  94   PACK_STRUCT_FLD_S(ip4_addr_p_t dest);
  95 } PACK_STRUCT_STRUCT;
  96 PACK_STRUCT_END
  97 #ifdef PACK_STRUCT_USE_INCLUDES
  98 #  include "arch/epstruct.h"
  99 #endif
 100
 101 /* Macros to get struct ip_hdr fields: */
 102 #define IPH_V(hdr)  ((hdr)->_v_hl >> 4)
 103 #define IPH_HL(hdr) ((hdr)->_v_hl & 0x0f)
 104 #define IPH_TOS(hdr) ((hdr)->_tos)
 105 #define IPH_LEN(hdr) ((hdr)->_len)
 106 #define IPH_ID(hdr) ((hdr)->_id)
 107 #define IPH_OFFSET(hdr) ((hdr)->_offset)
 108 #define IPH_TTL(hdr) ((hdr)->_ttl)
 109 #define IPH_PROTO(hdr) ((hdr)->_proto)
 110 #define IPH_CHKSUM(hdr) ((hdr)->_chksum)
 111
 112 /* Macros to set struct ip_hdr fields: */
 113 #define IPH_VHL_SET(hdr, v, hl) (hdr)->_v_hl = (u8_t)((((v) << 4) | (hl)))
 114 #define IPH_TOS_SET(hdr, tos) (hdr)->_tos = (tos)
 115 #define IPH_LEN_SET(hdr, len) (hdr)->_len = (len)
 116 #define IPH_ID_SET(hdr, id) (hdr)->_id = (id)
 117 #define IPH_OFFSET_SET(hdr, off) (hdr)->_offset = (off)
 118 #define IPH_TTL_SET(hdr, ttl) (hdr)->_ttl = (u8_t)(ttl)
 119 #define IPH_PROTO_SET(hdr, proto) (hdr)->_proto = (u8_t)(proto)
 120 #define IPH_CHKSUM_SET(hdr, chksum) (hdr)->_chksum = (chksum)
 121
 122
 123 #ifdef __cplusplus
 124 }
 125 #endif
 126
 127 #endif /* LWIP_HDR_PROT_IP4_H */