1 /* 2 * Copyright (c) 1986, 1993 3 * The Regents of the University of California. 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_arp.h 8.1 (Berkeley) 6/10/93 34 */ 35 36 /* 37 * Address Resolution Protocol. 38 * 39 * See RFC 826 for protocol description. ARP packets are variable 40 * in size; the arphdr structure defines the fixed-length portion. 41 * Protocol type values are the same as those for 10 Mb/s Ethernet. 42 * It is followed by the variable-sized fields ar_sha, arp_spa, 43 * arp_tha and arp_tpa in that order, according to the lengths 44 * specified. Field names used correspond to RFC 826. 45 */ 46 struct arphdr { 47 u_short ar_hrd; /* format of hardware address */ 48 #define ARPHRD_ETHER 1 /* ethernet hardware format */ 49 #define ARPHRD_FRELAY 15 /* frame relay hardware format */ 50 u_short ar_pro; /* format of protocol address */ 51 u_char ar_hln; /* length of hardware address */ 52 u_char ar_pln; /* length of protocol address */ 53 u_short ar_op; /* one of: */ 54 #define ARPOP_REQUEST 1 /* request to resolve address */ 55 #define ARPOP_REPLY 2 /* response to previous request */ 56 #define ARPOP_REVREQUEST 3 /* request protocol address given hardware */ 57 #define ARPOP_REVREPLY 4 /* response giving protocol address */ 58 #define ARPOP_INVREQUEST 8 /* request to identify peer */ 59 #define ARPOP_INVREPLY 9 /* response identifying peer */ 60 /* 61 * The remaining fields are variable in size, 62 * according to the sizes above. 63 */ 64 #ifdef COMMENT_ONLY 65 u_char ar_sha[]; /* sender hardware address */ 66 u_char ar_spa[]; /* sender protocol address */ 67 u_char ar_tha[]; /* target hardware address */ 68 u_char ar_tpa[]; /* target protocol address */ 69 #endif 70 }; 71 72 /* 73 * ARP ioctl request 74 */ 75 struct arpreq { 76 struct sockaddr arp_pa; /* protocol address */ 77 struct sockaddr arp_ha; /* hardware address */ 78 int arp_flags; /* flags */ 79 }; 80 /* arp_flags and at_flags field values */ 81 #define ATF_INUSE 0x01 /* entry in use */ 82 #define ATF_COM 0x02 /* completed entry (enaddr valid) */ 83 #define ATF_PERM 0x04 /* permanent entry */ 84 #define ATF_PUBL 0x08 /* publish entry (respond for other host) */ 85 #define ATF_USETRAILERS 0x10 /* has requested trailers */ 86