text: /*	$NetBSD: if_ether.h,v 1.25 1997/01/17 17:06:06 mikel Exp $	*/
  
  /*
   * Copyright (c) 1982, 1986, 1993
   *	The 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. 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.
   *
   *	@(#)if_ether.h	8.1 (Berkeley) 6/10/93
   *
   * $FreeBSD: src/lib/libstand/if_ether.h,v 1.1.1.1.6.1 2000/09/20 09:49:17 jkh Exp $
   * $DragonFly: src/lib/libstand/if_ether.h,v 1.2 2003/06/17 04:26:51 dillon Exp $
   */
  
  /*
   * Ethernet address - 6 octets
   * this is only used by the ethers(3) functions.
   */
  struct ether_addr {
  	u_int8_t ether_addr_octet[6];
  };
  
  /*
   * Structure of a 10Mb/s Ethernet header.
   */
  #define	ETHER_ADDR_LEN	6
  
  struct	ether_header {
  	u_int8_t  ether_dhost[ETHER_ADDR_LEN];
  	u_int8_t  ether_shost[ETHER_ADDR_LEN];
  	u_int16_t ether_type;
  };
  
  #define	ETHERTYPE_PUP		0x0200	/* PUP protocol */
  #define	ETHERTYPE_IP		0x0800	/* IP protocol */
  #define	ETHERTYPE_ARP		0x0806	/* address resolution 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	ETHER_IS_MULTICAST(addr) (*(addr) & 0x01) /* is address mcast/bcast? */
  
  #define	ETHERMTU	1500
  #define	ETHERMIN	(60-14)
  
  #ifdef _KERNEL
  /*
   * 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_int8_t enaddr[ETHER_ADDR_LEN]; */				\
  {									\
  	(enaddr)[0] = 0x01;						\
  	(enaddr)[1] = 0x00;						\
  	(enaddr)[2] = 0x5e;						\
  	(enaddr)[3] = ((u_int8_t *)ipaddr)[1] & 0x7f;			\
  	(enaddr)[4] = ((u_int8_t *)ipaddr)[2];				\
  	(enaddr)[5] = ((u_int8_t *)ipaddr)[3];				\
  }
  #endif
  
  /*
   * 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_int8_t arp_sha[ETHER_ADDR_LEN];	/* sender hardware address */
  	u_int8_t arp_spa[4];			/* sender protocol address */
  	u_int8_t arp_tha[ETHER_ADDR_LEN];	/* target hardware address */
  	u_int8_t 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_int8_t ac_enaddr[ETHER_ADDR_LEN];	/* ethernet hardware address */
  	char	 ac__pad[2];			/* be nice to m68k ports */
  	LIST_HEAD(, ether_multi) ac_multiaddrs;	/* list of ether multicast addrs */
  	int	 ac_multicnt;			/* length of ac_multiaddrs list */
  };
  
  struct llinfo_arp {
  	LIST_ENTRY(llinfo_arp) la_list;
  	struct	rtentry *la_rt;
  	struct	mbuf *la_hold;		/* last packet until resolved/timeout */
  	long	la_asked;		/* last time we QUERIED for this addr */
  #define la_timer la_rt->rt_rmx.rmx_expire /* deletion time in seconds */
  };
  
  struct sockaddr_inarp {
  	u_int8_t  sin_len;
  	u_int8_t  sin_family;
  	u_int16_t sin_port;
  	struct	  in_addr sin_addr;
  	struct	  in_addr sin_srcaddr;
  	u_int16_t sin_tos;
  	u_int16_t sin_other;
  #define SIN_PROXY 1
  };
  
  /*
   * IP and ethernet specific routing flags
   */
  #define	RTF_USETRAILERS	RTF_PROTO1	/* use trailers */
  #define	RTF_ANNOUNCE	RTF_PROTO2	/* announce new arp entry */
  
  #ifdef	_KERNEL
  u_int8_t etherbroadcastaddr[ETHER_ADDR_LEN];
  u_int8_t ether_ipmulticast_min[ETHER_ADDR_LEN];
  u_int8_t ether_ipmulticast_max[ETHER_ADDR_LEN];
  struct	ifqueue arpintrq;
  
  void	arpwhohas(struct arpcom *, struct in_addr *);
  void	arpintr(void);
  int	arpresolve(struct arpcom *,
  	    struct rtentry *, struct mbuf *, struct sockaddr *, u_char *);
  void	arp_ifinit(struct arpcom *, struct ifaddr *);
  void	arp_rtrequest(int, struct rtentry *, struct sockaddr *);
  
  int	ether_addmulti(struct ifreq *, struct arpcom *);
  int	ether_delmulti(struct ifreq *, struct arpcom *);
  #endif /* _KERNEL */
  
  /*
   * 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_int8_t enm_addrlo[ETHER_ADDR_LEN]; /* low  or only address of range */
  	u_int8_t enm_addrhi[ETHER_ADDR_LEN]; /* high or only address of range */
  	struct	 arpcom *enm_ac;	/* back pointer to arpcom */
  	u_int	 enm_refcount;		/* no. claims to this addr/range */
  	LIST_ENTRY(ether_multi) enm_list;
  };
  
  /*
   * 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;
  };
  
  /*
   * 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_int8_t addrlo[ETHER_ADDR_LEN]; */				\
  	/* u_int8_t addrhi[ETHER_ADDR_LEN]; */				\
  	/* struct arpcom *ac; */					\
  	/* struct ether_multi *enm; */					\
  {									\
  	for ((enm) = (ac)->ac_multiaddrs.lh_first;			\
  	    (enm) != NULL &&						\
  	    (bcmp((enm)->enm_addrlo, (addrlo), ETHER_ADDR_LEN) != 0 ||	\
  	     bcmp((enm)->enm_addrhi, (addrhi), ETHER_ADDR_LEN) != 0);	\
  		(enm) = (enm)->enm_list.le_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_list.le_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.lh_first; \
  	ETHER_NEXT_MULTI((step), (enm)); \
  }
  
  #ifdef _KERNEL
  void arp_rtrequest(int, struct rtentry *, struct sockaddr *);
  int arpresolve(struct arpcom *, struct rtentry *, struct mbuf *,
  		    struct sockaddr *, u_char *);
  void arpintr(void);
  int arpioctl(u_long, caddr_t);
  void arp_ifinit(struct arpcom *, struct ifaddr *);
  void revarpinput(struct mbuf *);
  void in_revarpinput(struct mbuf *);
  void revarprequest(struct ifnet *);
  int revarpwhoarewe(struct ifnet *, struct in_addr *, struct in_addr *);
  int revarpwhoami(struct in_addr *, struct ifnet *);
  int db_show_arptab(void);
  #endif
  
  /*
   * Prototype ethers(3) functions.
   */
  #ifndef _KERNEL
  #include <sys/cdefs.h>
  __BEGIN_DECLS
  char *	ether_ntoa(struct ether_addr *);
  struct ether_addr *
  	ether_aton(char *);
  int	ether_ntohost(char *, struct ether_addr *);
  int	ether_hostton(char *, struct ether_addr *);
  int	ether_line(char *, struct ether_addr *, char *);
  __END_DECLS
  #endif
  