Home | History | Annotate | Line # | Download | only in net
if_dl.h revision 1.8 
      1 /*	$NetBSD: if_dl.h,v 1.8 1995/03/26 20:30:13 jtc Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1990, 1993
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. All advertising materials mentioning features or use of this software
     16  *    must display the following acknowledgement:
     17  *	This product includes software developed by the University of
     18  *	California, Berkeley and its contributors.
     19  * 4. Neither the name of the University nor the names of its contributors
     20  *    may be used to endorse or promote products derived from this software
     21  *    without specific prior written permission.
     22  *
     23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     33  * SUCH DAMAGE.
     34  *
     35  *	@(#)if_dl.h	8.1 (Berkeley) 6/10/93
     36  */
     37 
     38 /*
     39  * A Link-Level Sockaddr may specify the interface in one of two
     40  * ways: either by means of a system-provided index number (computed
     41  * anew and possibly differently on every reboot), or by a human-readable
     42  * string such as "il0" (for managerial convenience).
     43  *
     44  * Census taking actions, such as something akin to SIOCGCONF would return
     45  * both the index and the human name.
     46  *
     47  * High volume transactions (such as giving a link-level ``from'' address
     48  * in a recvfrom or recvmsg call) may be likely only to provide the indexed
     49  * form, (which requires fewer copy operations and less space).
     50  *
     51  * The form and interpretation  of the link-level address is purely a matter
     52  * of convention between the device driver and its consumers; however, it is
     53  * expected that all drivers for an interface of a given if_type will agree.
     54  */
     55 
     56 /*
     57  * Structure of a Link-Level sockaddr:
     58  */
     59 struct sockaddr_dl {
     60 	u_char	  sdl_len;	/* Total length of sockaddr */
     61 	u_char	  sdl_family;	/* AF_DLI */
     62 	u_int16_t sdl_index;	/* if != 0, system given index for interface */
     63 	u_char	  sdl_type;	/* interface type */
     64 	u_char	  sdl_nlen;	/* interface name length, no trailing 0 reqd. */
     65 	u_char	  sdl_alen;	/* link level address length */
     66 	u_char	  sdl_slen;	/* link layer selector length */
     67 	char	  sdl_data[12];	/* minimum work area, can be larger;
     68 				   contains both if name and ll address */
     69 };
     70 
     71 #define LLADDR(s) ((caddr_t)((s)->sdl_data + (s)->sdl_nlen))
     72 
     73 #ifndef _KERNEL
     74 
     75 #include <sys/cdefs.h>
     76 
     77 __BEGIN_DECLS
     78 void	link_addr __P((const char *, struct sockaddr_dl *));
     79 char	*link_ntoa __P((const struct sockaddr_dl *));
     80 __END_DECLS
     81 
     82 #endif /* !_KERNEL */
     83