1 /* $OpenBSD: if_dl.h,v 1.12 2017/05/04 15:00:24 bluhm Exp $ */ 2 /* $NetBSD: if_dl.h,v 1.8 1995/03/26 20:30:13 jtc Exp $ */ 3 4 /* 5 * Copyright (c) 1990, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * @(#)if_dl.h 8.1 (Berkeley) 6/10/93 33 */ 34 35 /* 36 * A Link-Level Sockaddr may specify the interface in one of two 37 * ways: either by means of a system-provided index number (computed 38 * anew and possibly differently on every reboot), or by a human-readable 39 * string such as "il0" (for managerial convenience). 40 * 41 * Census taking actions, such as something akin to SIOCGCONF would return 42 * both the index and the human name. 43 * 44 * High volume transactions (such as giving a link-level ``from'' address 45 * in a recvfrom or recvmsg call) may be likely only to provide the indexed 46 * form, (which requires fewer copy operations and less space). 47 * 48 * The form and interpretation of the link-level address is purely a matter 49 * of convention between the device driver and its consumers; however, it is 50 * expected that all drivers for an interface of a given if_type will agree. 51 */ 52 53 #ifndef _NET_IF_DL_H_ 54 #define _NET_IF_DL_H_ 55 56 /* 57 * Structure of a Link-Level sockaddr: 58 */ 59 struct sockaddr_dl { 60 u_char sdl_len; /* Total length of sockaddr */ 61 u_char sdl_family; /* AF_LINK */ 62 u_int16_t sdl_index; /* if != 0, system given index for interface */ 63 u_char sdl_type; /* interface type */ 64 u_char sdl_nlen; /* interface name length, no trailing 0 reqd. */ 65 u_char sdl_alen; /* link level address length */ 66 u_char sdl_slen; /* link layer selector length, mostly 0 */ 67 char sdl_data[24]; /* minimum work area, can be larger; 68 contains both if name and ll address; 69 big enough for IFNAMSIZ plus 8byte ll addr */ 70 }; 71 72 #define LLADDR(s) ((caddr_t)((s)->sdl_data + (s)->sdl_nlen)) 73 74 #ifdef _KERNEL 75 76 static inline struct sockaddr_dl * 77 satosdl(struct sockaddr *sa) 78 { 79 return ((struct sockaddr_dl *)(sa)); 80 } 81 82 static inline struct sockaddr * 83 sdltosa(struct sockaddr_dl *sdl) 84 { 85 return ((struct sockaddr *)(sdl)); 86 } 87 88 #else /* _KERNEL */ 89 90 __BEGIN_DECLS 91 char *link_ntoa(const struct sockaddr_dl *); 92 __END_DECLS 93 94 #endif /* _KERNEL */ 95 #endif /* _NET_IF_DL_H_ */ 96