ip.h

用于嵌入式系统的TCP/IP协议栈

/***********************************************************************/
/*                                                                     */
/*   Module:  tcp_ip/ip/ip.h                                           */
/*   Release: 2001.3                                                   */
/*   Version: 99.0                                                     */
/*   Purpose: IP Private Header File                                   */
/*                                                                     */
/*---------------------------------------------------------------------*/
/*                                                                     */
/*               Copyright 1999, Blunk Microsystems                    */
/*                      ALL RIGHTS RESERVED                            */
/*                                                                     */
/*   Licensees have the non-exclusive right to use, modify, or extract */
/*   this computer program for software development at a single site.  */
/*   This program may be resold or disseminated in executable format   */
/*   only. The source code may not be redistributed or resold.         */
/*                                                                     */
/***********************************************************************/

/***********************************************************************/
/* Symbol Definitions                                                  */
/***********************************************************************/
/*
** Route Flags
*/
#define RT_BRDCST       (1 << 0)
#define RT_GATEWAY      (1 << 1)

/*
** Protocol Numbers
*/
#define IPT_ICMP    1   /* protocol type for ICMP packets */
#define IPT_IGMP    2   /* protocol type for IGMP packets */
#define IPT_TCP     6   /* protocol type for TCP packets */
#define IPT_EGP     8   /* protocol type for EGP packets */
#define IPT_UDP     17  /* protocol type for UDP packets */

/*
** IP Header Constants
*/
#define IP_VERSION  4   /* current version value */
#define IP_MAXOPT   40  /* largest option field, bytes */

#define IP_MF       0x2000  /* more fragments bit */
#define IP_DF       0x4000  /* don't fragment bit */
#define IP_FRAGOFF  0x1FFF  /* fragment offset mask */
#define IP_PREC     0xE0    /* precedence portion of TOS */

/*
** IP Options
*/
#define IPO_COPY    0x80    /* copy on fragment mask */
#define IPO_CLASS   0x60    /* option class */
#define IPO_NUM     0x1F    /* option number */
#define IPO_EOOP    0x00    /* end of options */
#define IPO_NOP     0x01    /* no operation */
#define IPO_SEC     0x82    /* DoD security/compartmentalization */
#define IPO_LSRCRT  0x83    /* loose source routing */
#define IPO_SSRCRT  0x89    /* strict source routing */
#define IPO_RECRT   0x07    /* record route */
#define IPO_STRID   0x88    /* stream ID */
#define IPO_TIME    0x44    /* internet timestamp */

/*
** ICMP Code Field
*/
#define ICC_NETUR   0   /* dest unreachable, net unreachable */
#define ICC_HOSTUR  1   /* dest unreachable, host unreachable */
#define ICC_PROTOUR 2   /* dest unreachable, proto unreachable */
#define ICC_PORTUR  3   /* dest unreachable, port unreachable */
#define ICC_FRAGREQ 4   /* dest unr, frag needed & don't frag */
#define ICC_SRCRT   5   /* dest unreachable, src route failed */
#define ICC_NETUNK  6   /* dest unreachable, dest network unknown */
#define ICC_HOSTUNK 7   /* dest unreachable, dest host unknown */
#define ICC_NETTYP  11  /* dest unr, network service type unreachable */
#define ICC_HOSTTYP 12  /* dest unr, host service type unreachable */
#define ICC_COMMPRO 13  /* dest unreachable, communication prohibited */
#define ICC_PRECVIO 14  /* dest unreachable, host precedence violation */
#define ICC_PRECCUT 15  /* dest unreachable, precedence cutoff */

#define ICC_NETRD   0   /* redirect: net */
#define ICC_HOSTRD  1   /* redirect: host */
#define IC_TOSNRD   2   /* redirect: type of service, net */
#define IC_TOSHRD   3   /* redirect: type of service, host */

#define ICC_TIMEX   0   /* time exceeded, ttl */
#define ICC_FTIMEX  1   /* time exceeded, frag */

/***********************************************************************/
/* Macro Definitions                                                   */
/***********************************************************************/
/*
** IP header length macro must work on possibly unaligned segments
*/
#define IP_HLEN(ip) \
  (((((ui8 *)(ip))[offsetof(Ip, ver_len)]) & 0xF) << 2)

/***********************************************************************/
/* Type Definitions                                                    */
/***********************************************************************/
/*
** IP Packet Structure
*/
typedef struct ip
{
  ui8  ver_len;         /* IP version & header length (in longs) */
  ui8  ip_tos;          /* type of service */
  ui16 length;          /* total packet length (in bytes) */
  ui16 ip_id;           /* datagram id */
  ui16 frag_off;        /* fragment offset (in 8-octet's) */
  ui8  ttl;             /* time to live, in gateway hops */
  ui8  protocol;        /* IP protocol */
  ui16 checksum;        /* header checksum */
  ui32 src_ip;          /* IP address of source */
  ui32 dst_ip;          /* IP address of destination */
  ui8  options[IP_MAXOPT];      /* variable length options */
} Ip;

/*
** Routing Table Entry Structure
*/
struct route
{
  ui32 addr;            /* network or host address */
  ui32 mask;            /* mask for this route */
  ui32 gw;              /* next IP hop */
  Ni  *ni;              /* pointer to network interface structure */
  struct route *next;   /* next entry for this hash value */
  ui8  key;             /* sort key (number of 1's) */
  ui16 flags;           /* RT_BRDCST, etc. */
};

/***********************************************************************/
/* Function Prototypes                                                 */
/***********************************************************************/
ui16 IpChecksum(void *src, uint len);
void IpSend(const Route *route, NetBuf *buf, int datalen, ui8 tos);
void IpOut(void *object);
ui32 IpNetMask(ui32 net);
ui32 IpSubnetMask(ui32 net);
void IpLocalIn(void);

/*
** Fragmentation related
*/
int  IpJoinFrag(void);
void IpFragInit(void);

/*
** Routing related
*/
void RtInit(void);
int  RtAdd(ui32 gw, ui32 mask, ui32 addr, Ni *ni, int flags);
int  RtDel(ui32 gw, ui32 mask, ui32 addr);
void RtDump(void);
void NiRtDel(Ni *ni);
Route *RtSearch(ui32 dest);