sys/net/if_dl.h

   1 /*
   2  * Copyright (c) 1990, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  *      @(#)if_dl.h     8.1 (Berkeley) 6/10/93
  30  * $FreeBSD: src/sys/net/if_dl.h,v 1.10 2000/03/01 02:46:25 archie Exp $
  31  * $DragonFly: src/sys/net/if_dl.h,v 1.4 2006/05/20 02:42:08 dillon Exp $
  32  */
  33
  34 #ifndef _NET_IF_DL_H_
  35 #define _NET_IF_DL_H_
  36
  37 #ifndef _SYS_TYPES_H_
  38 #include <sys/types.h>
  39 #endif
  40
  41 /*
  42  * A Link-Level Sockaddr may specify the interface in one of two
  43  * ways: either by means of a system-provided index number (computed
  44  * anew and possibly differently on every reboot), or by a human-readable
  45  * string such as "il0" (for managerial convenience).
  46  *
  47  * Census taking actions, such as something akin to SIOCGCONF would return
  48  * both the index and the human name.
  49  *
  50  * High volume transactions (such as giving a link-level ``from'' address
  51  * in a recvfrom or recvmsg call) may be likely only to provide the indexed
  52  * form, (which requires fewer copy operations and less space).
  53  *
  54  * The form and interpretation  of the link-level address is purely a matter
  55  * of convention between the device driver and its consumers; however, it is
  56  * expected that all drivers for an interface of a given if_type will agree.
  57  */
  58
  59 /*
  60  * Structure of a Link-Level sockaddr:
  61  */
  62 struct sockaddr_dl {
  63         u_char  sdl_len;        /* Total length of sockaddr */
  64         u_char  sdl_family;     /* AF_LINK */
  65         u_short sdl_index;      /* if != 0, system given index for interface */
  66         u_char  sdl_type;       /* interface type */
  67         u_char  sdl_nlen;       /* interface name length, no trailing 0 reqd. */
  68         u_char  sdl_alen;       /* link level address length */
  69         u_char  sdl_slen;       /* link layer selector length */
  70         char    sdl_data[12];   /* minimum work area, can be larger;
  71                                    contains both if name and ll address */
  72         u_short sdl_rcf;        /* source routing control */
  73         u_short sdl_route[16];  /* source routing information */
  74 };
  75
  76 #define LLADDR(s) ((caddr_t)((s)->sdl_data + (s)->sdl_nlen))
  77
  78 #ifndef _KERNEL
  79
  80 #include <sys/cdefs.h>
  81
  82 __BEGIN_DECLS
  83 void    link_addr (const char *, struct sockaddr_dl *);
  84 char    *link_ntoa (const struct sockaddr_dl *);
  85 __END_DECLS
  86
  87 #endif /* !_KERNEL */
  88
  89 #endif