ip.h

LwIP是瑞士计算机科学院(Swedish Institute of Computer Science)的AdamDunkels等开发的一套用于嵌入式系统的开放源代码TCP/IP协议栈。LwIP的含义

/*
 * 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 <[e-mail]>
 *
 */
#ifndef __LWIP_IP_H__
#define __LWIP_IP_H__

#include "lwip/arch.h"

#include "lwip/def.h"
#include "lwip/pbuf.h"
#include "lwip/ip_addr.h"

#include "lwip/err.h"


void ip_init(void);
struct netif *ip_route(struct ip_addr *dest);
err_t ip_input(struct pbuf *p, struct netif *inp);
err_t ip_output(struct pbuf *p, struct ip_addr *src, struct ip_addr *dest,
    u8_t ttl, u8_t tos, u8_t proto);
err_t ip_output_if(struct pbuf *p, struct ip_addr *src, struct ip_addr *dest,
       u8_t ttl, u8_t tos, u8_t proto,
       struct netif *netif);

#define IP_HLEN 20

#define IP_PROTO_ICMP 1
#define IP_PROTO_UDP 17
#define IP_PROTO_UDPLITE 136
#define IP_PROTO_TCP 6

/* This is passed as the destination address to ip_output_if (not
   to ip_output), meaning that an IP header already is constructed
   in the pbuf. This is used when TCP retransmits. */
#ifdef IP_HDRINCL
#undef IP_HDRINCL
#endif /* IP_HDRINCL */
#define IP_HDRINCL  NULL


/* This is the common part of all PCB types. It needs to be at the
   beginning of a PCB type definition. It is located here so that
   changes to this common part are made in one location instead of
   having to change all PCB structs. */
#define IP_PCB struct ip_addr local_ip; \
  struct ip_addr remote_ip; \
   /* Socket options */  \
  u16_t so_options;      \
   /* Type Of Service */ \
  u8_t tos;              \
  /* Time To Live */     \
  u8_t ttl

/*
 * Option flags per-socket. These are the same like SO_XXX.
 */
#define SOF_DEBUG     (u16_t)0x0001U    /* turn on debugging info recording */
#define SOF_ACCEPTCONN  (u16_t)0x0002U    /* socket has had listen() */
#define SOF_REUSEADDR (u16_t)0x0004U    /* allow local address reuse */
#define SOF_KEEPALIVE (u16_t)0x0008U    /* keep connections alive */
#define SOF_DONTROUTE (u16_t)0x0010U    /* just use interface addresses */
#define SOF_BROADCAST (u16_t)0x0020U    /* permit sending of broadcast msgs */
#define SOF_USELOOPBACK (u16_t)0x0040U    /* bypass hardware when possible */
#define SOF_LINGER      (u16_t)0x0080U    /* linger on close if data present */
#define SOF_OOBINLINE (u16_t)0x0100U    /* leave received OOB data in line */
#define SOF_REUSEPORT (u16_t)0x0200U    /* allow local address & port reuse */



#ifdef PACK_STRUCT_USE_INCLUDES
#  include "arch/bpstruct.h"
#endif
PACK_STRUCT_BEGIN
struct ip_hdr {
  /* version / header length / type of service */
  PACK_STRUCT_FIELD(u16_t _v_hl_tos);
  /* total length */
  PACK_STRUCT_FIELD(u16_t _len);
  /* identification */
  PACK_STRUCT_FIELD(u16_t _id);
  /* fragment offset field */
  PACK_STRUCT_FIELD(u16_t _offset);
#define IP_RF 0x8000        /* reserved fragment flag */
#define IP_DF 0x4000        /* dont fragment flag */
#define IP_MF 0x2000        /* more fragments flag */
#define IP_OFFMASK 0x1fff   /* mask for fragmenting bits */
  /* time to live / protocol*/
  PACK_STRUCT_FIELD(u16_t _ttl_proto);
  /* checksum */
  PACK_STRUCT_FIELD(u16_t _chksum);
  /* source and destination IP addresses */
  PACK_STRUCT_FIELD(struct ip_addr src);
  PACK_STRUCT_FIELD(struct ip_addr dest); 
} PACK_STRUCT_STRUCT;
PACK_STRUCT_END
#ifdef PACK_STRUCT_USE_INCLUDES
#  include "arch/epstruct.h"
#endif

#define IPH_V(hdr)  (ntohs((hdr)->_v_hl_tos) >> 12)
#define IPH_HL(hdr) ((ntohs((hdr)->_v_hl_tos) >> 8) & 0x0f)
#define IPH_TOS(hdr) (ntohs((hdr)->_v_hl_tos) & 0xff)
#define IPH_LEN(hdr) ((hdr)->_len)
#define IPH_ID(hdr) ((hdr)->_id)
#define IPH_OFFSET(hdr) ((hdr)->_offset)
#define IPH_TTL(hdr) (ntohs((hdr)->_ttl_proto) >> 8)
#define IPH_PROTO(hdr) (ntohs((hdr)->_ttl_proto) & 0xff)
#define IPH_CHKSUM(hdr) ((hdr)->_chksum)

#define IPH_VHLTOS_SET(hdr, v, hl, tos) (hdr)->_v_hl_tos = (htons(((v) << 12) | ((hl) << 8) | (tos)))
#define IPH_LEN_SET(hdr, len) (hdr)->_len = (len)
#define IPH_ID_SET(hdr, id) (hdr)->_id = (id)
#define IPH_OFFSET_SET(hdr, off) (hdr)->_offset = (off)
#define IPH_TTL_SET(hdr, ttl) (hdr)->_ttl_proto = (htons(IPH_PROTO(hdr) | ((u16_t)(ttl) << 8)))
#define IPH_PROTO_SET(hdr, proto) (hdr)->_ttl_proto = (htons((proto) | (IPH_TTL(hdr) << 8)))
#define IPH_CHKSUM_SET(hdr, chksum) (hdr)->_chksum = (chksum)

#if IP_DEBUG
void ip_debug_print(struct pbuf *p);
#else
#define ip_debug_print(p)
#endif /* IP_DEBUG */

#endif /* __LWIP_IP_H__ */