1 /* 2 * Copyright (c) 1990 Regents of the University of California. 3 * 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. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)if_dl.h 7.2 (Berkeley) 2/22/91 34 */ 35 36 /* 37 * A Link-Level Sockaddr may specify the interface in one of two 38 * ways: either by means of a system-provided index number (computed 39 * anew and possibly differently on every reboot), or by a human-readable 40 * string such as "il0" (for managerial convenience). 41 * 42 * Census taking actions, such as something akin to SIOCGCONF would return 43 * both the index and the human name. 44 * 45 * High volume transactions (such as giving a link-level ``from'' address 46 * in a recvfrom or recvmsg call) may be likely only to provide the indexed 47 * form, (which requires fewer copy operations and less space). 48 * 49 * The form and interpretation of the link-level address is purely a matter 50 * of convention between the device driver and its consumers; however, it is 51 * expected that all drivers for an interface of a given if_type will agree. 52 */ 53 54 /* 55 * Structure of a Link-Level sockaddr: 56 */ 57 struct sockaddr_dl { 58 u_char sdl_len; /* Total length of sockaddr */ 59 u_char sdl_family; /* AF_DLI */ 60 u_short sdl_index; /* if != 0, system given index for interface */ 61 u_char sdl_type; /* interface type */ 62 u_char sdl_nlen; /* interface name length, no trailing 0 reqd. */ 63 u_char sdl_alen; /* link level address length */ 64 u_char sdl_slen; /* link layer selector length */ 65 char sdl_data[12]; /* minimum work area, can be larger; 66 contains both if name and ll address */ 67 }; 68 69 #define LLADDR(s) ((caddr_t)((s)->sdl_data + (s)->sdl_nlen)) 70 71 #ifndef KERNEL 72 73 #include <sys/cdefs.h> 74 75 __BEGIN_DECLS 76 void link_addr __P((const char *, struct sockaddr_dl *)); 77 char *link_ntoa __P((const struct sockaddr_dl *)); 78 __END_DECLS 79 80 #endif /* !KERNEL */ 81