/*
* Copyright (c) 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)if_dl.h 8.1 (Berkeley) 6/10/93
*/
/*
* A Link-Level Sockaddr may specify the interface in one of two
* ways: either by means of a system-provided index number (computed
* anew and possibly differently on every reboot), or by a human-readable
* string such as "il0" (for managerial convenience).
*
* Census taking actions, such as something akin to SIOCGCONF would return
* both the index and the human name.
*
* High volume transactions (such as giving a link-level ``from'' address
* in a recvfrom or recvmsg call) may be likely only to provide the indexed
* form, (which requires fewer copy operations and less space).
*
* The form and interpretation of the link-level address is purely a matter
* of convention between the device driver and its consumers; however, it is
* expected that all drivers for an interface of a given if_type will agree.
*/
struct dl_addr {
uint8_t dl_type; /* interface type */
uint8_t dl_nlen; /* interface name length, no trailing 0 reqd. */
uint8_t dl_alen; /* link level address length */
uint8_t dl_slen; /* link layer selector length */
char dl_data[24]; /*
* minimum work area, can be larger; contains
* both if name and ll address; big enough for
* IFNAMSIZ plus 8byte ll addr.
*/
};
/*
* Structure of a Link-Level sockaddr:
*/
struct sockaddr_dl {
uint8_t sdl_len; /* Total length of sockaddr */
sa_family_t sdl_family; /* AF_LINK */
uint16_t sdl_index; /* if != 0, system given index for interface */
struct dl_addr sdl_addr;
#define sdl_type sdl_addr.dl_type
#define sdl_nlen sdl_addr.dl_nlen
#define sdl_alen sdl_addr.dl_alen
#define sdl_slen sdl_addr.dl_slen
#define sdl_data sdl_addr.dl_data
};
/* We do arithmetic directly with these, so keep them char instead of void */
#define LLADDR(s) ((char *)((s)->sdl_data + (s)->sdl_nlen))
#define CLLADDR(s) ((const char *)((s)->sdl_data + (s)->sdl_nlen))
