1 /* $NetBSD: if_arp.h,v 1.8 1995/03/08 02:56:52 cgd Exp $ */ 2 3 /* 4 * Copyright (c) 1986, 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. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)if_arp.h 8.1 (Berkeley) 6/10/93 36 */ 37 38 /* 39 * Address Resolution Protocol. 40 * 41 * See RFC 826 for protocol description. ARP packets are variable 42 * in size; the arphdr structure defines the fixed-length portion. 43 * Protocol type values are the same as those for 10 Mb/s Ethernet. 44 * It is followed by the variable-sized fields ar_sha, arp_spa, 45 * arp_tha and arp_tpa in that order, according to the lengths 46 * specified. Field names used correspond to RFC 826. 47 */ 48 struct arphdr { 49 u_int16_t ar_hrd; /* format of hardware address */ 50 #define ARPHRD_ETHER 1 /* ethernet hardware format */ 51 #define ARPHRD_FRELAY 15 /* frame relay hardware format */ 52 u_int16_t ar_pro; /* format of protocol address */ 53 u_int8_t ar_hln; /* length of hardware address */ 54 u_int8_t ar_pln; /* length of protocol address */ 55 u_int16_t ar_op; /* one of: */ 56 #define ARPOP_REQUEST 1 /* request to resolve address */ 57 #define ARPOP_REPLY 2 /* response to previous request */ 58 #define ARPOP_REVREQUEST 3 /* request protocol address given hardware */ 59 #define ARPOP_REVREPLY 4 /* response giving protocol address */ 60 #define ARPOP_INVREQUEST 8 /* request to identify peer */ 61 #define ARPOP_INVREPLY 9 /* response identifying peer */ 62 /* 63 * The remaining fields are variable in size, 64 * according to the sizes above. 65 */ 66 #ifdef COMMENT_ONLY 67 u_int8_t ar_sha[]; /* sender hardware address */ 68 u_int8_t ar_spa[]; /* sender protocol address */ 69 u_int8_t ar_tha[]; /* target hardware address */ 70 u_int8_t ar_tpa[]; /* target protocol address */ 71 #endif 72 }; 73 74 /* 75 * ARP ioctl request 76 */ 77 struct arpreq { 78 struct sockaddr arp_pa; /* protocol address */ 79 struct sockaddr arp_ha; /* hardware address */ 80 int arp_flags; /* flags */ 81 }; 82 /* arp_flags and at_flags field values */ 83 #define ATF_INUSE 0x01 /* entry in use */ 84 #define ATF_COM 0x02 /* completed entry (enaddr valid) */ 85 #define ATF_PERM 0x04 /* permanent entry */ 86 #define ATF_PUBL 0x08 /* publish entry (respond for other host) */ 87 #define ATF_USETRAILERS 0x10 /* has requested trailers */ 88