if_arp.h

<B>Digital的Unix操作系统VAX 4.2源码</B>

/*
 *	@(#)if_arp.h	4.1	(ULTRIX)	7/2/90
 */ 
/************************************************************************
 *									*
 *			Copyright (c) 1984 by				*
 *		Digital Equipment Corporation, Maynard, MA		*
 *			All rights reserved.				*
 *									*
 *   This software is furnished under a license and may be used and	*
 *   copied  only  in accordance with the terms of such license and	*
 *   with the  inclusion  of  the  above  copyright  notice.   This	*
 *   software  or  any  other copies thereof may not be provided or	*
 *   otherwise made available to any other person.  No title to and	*
 *   ownership of the software is hereby transferred.			*
 *									*
 *   This software is  derived  from  software  received  from  the	*
 *   University    of   California,   Berkeley,   and   from   Bell	*
 *   Laboratories.  Use, duplication, or disclosure is  subject  to	*
 *   restrictions  under  license  agreements  with  University  of	*
 *   California and with AT&T.						*
 *									*
 *   The information in this software is subject to change  without	*
 *   notice  and should not be construed as a commitment by Digital	*
 *   Equipment Corporation.						*
 *									*
 *   Digital assumes no responsibility for the use  or  reliability	*
 *   of its software on equipment which is not supplied by Digital.	*
 *									*
 ************************************************************************/
/*
 *	
 *	15-Jan-88	lp
 *		Merge of final 43BSD changes.
 *
 */ 
/*
 * Copyright (c) 1986 Regents of the University of California.
 * All rights reserved.  The Berkeley software License Agreement
 * specifies the terms and conditions for redistribution.
 *
 *	if_arp.h	7.1 (Berkeley) 6/4/86
 */

/*
 * Address Resolution Protocol.
 *
 * See RFC 826 for protocol description.  ARP packets are variable
 * in size; the arphdr structure defines the fixed-length portion.
 * Protocol type values are the same as those for 10 Mb/s Ethernet.
 * It is followed by the variable-sized fields ar_sha, arp_spa,
 * arp_tha and arp_tpa in that order, according to the lengths
 * specified.  Field names used correspond to RFC 826.
 */
struct	arphdr {
	u_short	ar_hrd;		/* format of hardware address */
#define ARPHRD_ETHER 	1	/* ethernet hardware address */
	u_short	ar_pro;		/* format of protocol address */
	u_char	ar_hln;		/* length of hardware address */
	u_char	ar_pln;		/* length of protocol address */
	u_short	ar_op;		/* one of: */
#define	ARPOP_REQUEST	1	/* request to resolve address */
#define	ARPOP_REPLY	2	/* response to previous request */
#define RARPOP_REQUEST  3       /* Reverse ARP request */
#define RARPOP_REPLY    4       /* Reverse ARP reply */

/*
 * The remaining fields are variable in size,
 * according to the sizes above.
 */
/*	u_char	ar_sha[];	/* sender hardware address */
/*	u_char	ar_spa[];	/* sender protocol address */
/*	u_char	ar_tha[];	/* target hardware address */
/*	u_char	ar_tpa[];	/* target protocol address */
};

/*
 * ARP ioctl request
 */
struct arpreq {
	struct	sockaddr arp_pa;		/* protocol address */
	struct	sockaddr arp_ha;		/* hardware address */
	int	arp_flags;			/* flags */
};
/*  arp_flags and at_flags field values */
#define	ATF_INUSE	0x01	/* entry in use */
#define ATF_COM		0x02	/* completed entry (enaddr valid) */
#define	ATF_PERM	0x04	/* permanent entry */
#define	ATF_PUBL	0x08	/* publish entry (respond for other host) */
#define	ATF_USETRAILERS	0x10	/* has requested trailers */

#define BSD_TRAILERS	1