/*!\file inc/netinet/if_ether.h
 * Ethernet definitions.
 */

/* Modified for emx by hv 1994
 *
 * Copyright (c) 1982, 1986 Regents of the University of California.
 * 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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.
 *
 *      from: @(#)if_ether.h    7.5 (Berkeley) 6/28/90
 *      $Id: if_ether.h,v 1.8 1994/02/02 05:58:54 hpeyerl Exp $
 */

#ifndef __NETINET_IF_ETHER_H
#define __NETINET_IF_ETHER_H

#include <sys/packon.h>

/*
 * Ethernet address - 6 octets
 * this is only used by the ethers(3) functions.
 */
struct ether_addr {
       u_char ether_addr_octet[6];
     };

/*
 * Structure of a 10Mb/s Ethernet header.
 */
struct ether_header {
       u_char  ether_dhost[6];
       u_char  ether_shost[6];
       u_short ether_type;
     };

#define ETHERTYPE_PUP           0x0200  /* PUP protocol */
/* the IBM header corrects the following to 0x608 for OS/2 but I believe
 * this is just a dirty hack 
 */
#define ETHERTYPE_ARP           0x0806  /* address resolution protocol */
#define ETHERTYPE_IP            0x0800  /* IP protocol */
#define ETHERTYPE_REVARP        0x8035  /* reverse addr resolution protocol */

/*
 * The ETHERTYPE_NTRAILER packet types starting at ETHERTYPE_TRAIL have
 * (type-ETHERTYPE_TRAIL)*512 bytes of data followed
 * by an ETHER type (as given above) and then the (variable-length) header.
 */
#define ETHERTYPE_TRAIL         0x1000          /* Trailer packet */
#define ETHERTYPE_NTRAILER      16

#define ETHERMTU                1500
#define ETHERMIN                (60-14)

/*
 * Macro to map an IP multicast address to an Ethernet multicast address.
 * The high-order 25 bits of the Ethernet address are statically assigned,
 * and the low-order 23 bits are taken from the low end of the IP address.
 */
#define ETHER_MAP_IP_MULTICAST(ipaddr, enaddr) \
        /* struct in_addr *ipaddr; */ \
        /* u_char enaddr[6];       */ \
        { \
          (enaddr)[0] = 0x01; \
          (enaddr)[1] = 0x00; \
          (enaddr)[2] = 0x5e; \
          (enaddr)[3] = ((u_char *)ipaddr)[1] & 0x7f; \
          (enaddr)[4] = ((u_char *)ipaddr)[2]; \
          (enaddr)[5] = ((u_char *)ipaddr)[3]; \
        }


/*
 * Ethernet Address Resolution Protocol.
 *
 * See RFC 826 for protocol description.  Structure below is adapted
 * to resolving internet addresses.  Field names used correspond to 
 * RFC 826.
 */
struct ether_arp {
       struct  arphdr ea_hdr;  /* fixed-size header */
       u_char  arp_sha[6];     /* sender hardware address */
       u_char  arp_spa[4];     /* sender protocol address */
       u_char  arp_tha[6];     /* target hardware address */
       u_char  arp_tpa[4];     /* target protocol address */
     };
#define arp_hrd ea_hdr.ar_hrd
#define arp_pro ea_hdr.ar_pro
#define arp_hln ea_hdr.ar_hln
#define arp_pln ea_hdr.ar_pln
#define arp_op  ea_hdr.ar_op


/*
 * Structure shared between the ethernet driver modules and
 * the address resolution code.  For example, each ec_softc or il_softc
 * begins with this structure.
 */
struct arpcom {
       struct  ifnet ac_if;               /* network-visible interface */
       u_char  ac_enaddr[6];              /* ethernet hardware address */
       struct in_addr ac_ipaddr;          /* copy of ip address- XXX */
       struct ether_multi *ac_multiaddrs; /* list of ether multicast addrs */
       int ac_multicnt;                   /* length of ac_multiaddrs list */
};

/*
 * Internet to ethernet address resolution table.
 */

struct arptab {
       struct  in_addr at_iaddr;       /* internet address */
       u_char  at_enaddr[6];           /* ethernet address */
       u_char  at_timer;               /* minutes since last reference */
       u_char  at_flags;               /* flags */
       struct  mbuf *at_hold;          /* last packet until resolved/timeout */
/* only os2 */
       u_short at_rcf;
       u_short at_rseg[8];
       u_long at_millisec;
       int at_interface;
};


extern u_char  etherbroadcastaddr[6];
extern u_char  ether_ipmulticast_min[6];
extern u_char  ether_ipmulticast_max[6];

/*
 * Ethernet multicast address structure.  There is one of these for each
 * multicast address or range of multicast addresses that we are supposed
 * to listen to on a particular interface.  They are kept in a linked list,
 * rooted in the interface's arpcom structure.  (This really has nothing to
 * do with ARP, or with the Internet address family, but this appears to be
 * the minimally-disrupting place to put it.)
 */
struct ether_multi {
       u_char  enm_addrlo[6];          /* low  or only address of range */
       u_char  enm_addrhi[6];          /* high or only address of range */
       struct  arpcom *enm_ac;         /* back pointer to arpcom */
       u_int   enm_refcount;           /* no. claims to this addr/range */
       struct  ether_multi *enm_next;  /* ptr to next ether_multi */
     };

/*
 * Structure used by macros below to remember position when stepping through
 * all of the ether_multi records.
 */
struct ether_multistep {
       struct ether_multi  *e_enm;
     };

#include <sys/packoff.h>

/*
 * Macro for looking up the ether_multi record for a given range of Ethernet
 * multicast addresses connected to a given arpcom structure.  If no matching
 * record is found, "enm" returns NULL.
 */
#define ETHER_LOOKUP_MULTI(addrlo, addrhi, ac, enm) \
        /* u_char addrlo[6]; */ \
        /* u_char addrhi[6]; */ \
        /* struct arpcom *ac; */ \
        /* struct ether_multi *enm; */ \
{ \
        for ((enm) = (ac)->ac_multiaddrs; \
            (enm) != NULL && \
            (bcmp((enm)->enm_addrlo, (addrlo), 6) != 0 || \
             bcmp((enm)->enm_addrhi, (addrhi), 6) != 0); \
                (enm) = (enm)->enm_next); \
}

/*
 * Macro to step through all of the ether_multi records, one at a time.
 * The current position is remembered in "step", which the caller must
 * provide.  ETHER_FIRST_MULTI(), below, must be called to initialize "step"
 * and get the first record.  Both macros return a NULL "enm" when there
 * are no remaining records.
 */
#define ETHER_NEXT_MULTI(step, enm) \
        /* struct ether_multistep step; */  \
        /* struct ether_multi *enm; */  \
{ \
        if (((enm) = (step).e_enm) != NULL) \
                (step).e_enm = (enm)->enm_next; \
}

#define ETHER_FIRST_MULTI(step, ac, enm) \
        /* struct ether_multistep step; */ \
        /* struct arpcom *ac; */ \
        /* struct ether_multi *enm; */ \
{ \
        (step).e_enm = (ac)->ac_multiaddrs; \
        ETHER_NEXT_MULTI((step), (enm)); \
}

#endif
