1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 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 32 #ifndef _NET_IF_DL_H_ 33 #define _NET_IF_DL_H_ 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 /* 54 * Structure of a Link-Level sockaddr: 55 */ 56 struct sockaddr_dl { 57 u_char sdl_len; /* Total length of sockaddr */ 58 u_char sdl_family; /* AF_LINK */ 59 u_short sdl_index; /* if != 0, system given index for interface */ 60 u_char sdl_type; /* interface type */ 61 u_char sdl_nlen; /* interface name length, no trailing 0 reqd. */ 62 u_char sdl_alen; /* link level address length */ 63 u_char sdl_slen; /* link layer selector length */ 64 char sdl_data[46]; /* minimum work area, can be larger; 65 contains both if name and ll address */ 66 }; 67 68 #define LLADDR(s) ((caddr_t)((s)->sdl_data + (s)->sdl_nlen)) 69 #define LLINDEX(s) ((s)->sdl_index) 70 71 struct ifnet; 72 struct sockaddr_dl *link_alloc_sdl(size_t, int); 73 void link_free_sdl(struct sockaddr *sa); 74 struct sockaddr_dl *link_init_sdl(struct ifnet *, struct sockaddr *, u_char); 75 76 #ifndef _KERNEL 77 78 #include <sys/cdefs.h> 79 80 __BEGIN_DECLS 81 void link_addr(const char *, struct sockaddr_dl *); 82 char *link_ntoa(const struct sockaddr_dl *); 83 __END_DECLS 84 85 #endif /* !_KERNEL */ 86 87 #endif 88