sys/net/if_dl.h

   1 /*      $NetBSD: if_dl.h,v 1.22 2008/02/20 17:05:52 matt 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. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  *
  31  *      @(#)if_dl.h     8.1 (Berkeley) 6/10/93
  32  */
  33
  34 /*
  35  * A Link-Level Sockaddr may specify the interface in one of two
  36  * ways: either by means of a system-provided index number (computed
  37  * anew and possibly differently on every reboot), or by a human-readable
  38  * string such as "il0" (for managerial convenience).
  39  *
  40  * Census taking actions, such as something akin to SIOCGCONF would return
  41  * both the index and the human name.
  42  *
  43  * High volume transactions (such as giving a link-level ``from'' address
  44  * in a recvfrom or recvmsg call) may be likely only to provide the indexed
  45  * form, (which requires fewer copy operations and less space).
  46  *
  47  * The form and interpretation  of the link-level address is purely a matter
  48  * of convention between the device driver and its consumers; however, it is
  49  * expected that all drivers for an interface of a given if_type will agree.
  50  */
  51
  52 #ifndef _NET_IF_DL_H_
  53 #define _NET_IF_DL_H_
  54
  55 #include <sys/ansi.h>
  56
  57 #ifndef sa_family_t
  58 typedef __sa_family_t   sa_family_t;
  59 #define sa_family_t     __sa_family_t
  60 #endif
  61
  62 /*
  63  * Structure of a Link-Level sockaddr:
  64  */
  65 struct sockaddr_dl {
  66         uint8_t     sdl_len;    /* Total length of sockaddr */
  67         sa_family_t sdl_family; /* AF_LINK */
  68         uint16_t   sdl_index;   /* if != 0, system given index for interface */
  69         uint8_t     sdl_type;   /* interface type */
  70         uint8_t     sdl_nlen;   /* interface name length, no trailing 0 reqd. */
  71         uint8_t     sdl_alen;   /* link level address length */
  72         uint8_t     sdl_slen;   /* link layer selector length */
  73         /* minimum work area, can be larger; contains both if name
  74          * and ll address
  75          */
  76         char        sdl_data[12];
  77 };
  78
  79 #define satosdl(__sa)   ((struct sockaddr_dl *)(__sa))
  80 #define satocsdl(__sa)  ((const struct sockaddr_dl *)(__sa))
  81
  82 /* We do arithmetic directly with these, so keep them char instead of void */
  83 #define LLADDR(s) ((char *)((s)->sdl_data + (s)->sdl_nlen))
  84 #define CLLADDR(s) ((const char *)((s)->sdl_data + (s)->sdl_nlen))
  85
  86 #ifdef _KERNEL
  87 uint8_t sockaddr_dl_measure(uint8_t, uint8_t);
  88 struct sockaddr *sockaddr_dl_alloc(uint16_t, uint8_t,
  89     const void *, uint8_t, const void *, uint8_t, int);
  90 struct sockaddr_dl *sockaddr_dl_init(struct sockaddr_dl *, socklen_t, uint16_t,
  91     uint8_t, const void *, uint8_t, const void *, uint8_t);
  92 struct sockaddr_dl *sockaddr_dl_setaddr(struct sockaddr_dl *, socklen_t,
  93     const void *, uint8_t);
  94 #else
  95
  96 #include <sys/cdefs.h>
  97
  98 __BEGIN_DECLS
  99 void    link_addr(const char *, struct sockaddr_dl *);
 100 char    *link_ntoa(const struct sockaddr_dl *);
 101 __END_DECLS
 102
 103 #endif /* !_KERNEL */
 104
 105 #endif /* !_NET_IF_DL_H_ */