xref: /netbsd-src/sys/net/if_dl.h (revision 5e4c038a45edbc7d63b7c2daa76e29f88b64a4e3)
1 /*	$NetBSD: if_dl.h,v 1.11 2000/07/28 12:13:32 kleink 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 #ifndef _NET_IF_DL_H_
57 #define _NET_IF_DL_H_
58 
59 #include <sys/ansi.h>
60 
61 #ifndef sa_family_t
62 typedef __sa_family_t	sa_family_t;
63 #define sa_family_t	__sa_family_t
64 #endif
65 
66 /*
67  * Structure of a Link-Level sockaddr:
68  */
69 struct sockaddr_dl {
70 	u_char	    sdl_len;	/* Total length of sockaddr */
71 	sa_family_t sdl_family;	/* AF_DLI */
72 	u_int16_t   sdl_index;	/* if != 0, system given index for interface */
73 	u_char	    sdl_type;	/* interface type */
74 	u_char	    sdl_nlen;	/* interface name length, no trailing 0 reqd. */
75 	u_char	    sdl_alen;	/* link level address length */
76 	u_char	    sdl_slen;	/* link layer selector length */
77 	char	    sdl_data[12]; /* minimum work area, can be larger;
78 				     contains both if name and ll address */
79 };
80 
81 #define LLADDR(s) ((caddr_t)((s)->sdl_data + (s)->sdl_nlen))
82 
83 #ifndef _KERNEL
84 
85 #include <sys/cdefs.h>
86 
87 __BEGIN_DECLS
88 void	link_addr __P((const char *, struct sockaddr_dl *));
89 char	*link_ntoa __P((const struct sockaddr_dl *));
90 __END_DECLS
91 
92 #endif /* !_KERNEL */
93 
94 #endif /* _NET_IF_DL_H_ */
95