125972Skarels /* 225972Skarels * Copyright (c) 1986 Regents of the University of California. 3*33183Sbostic * All rights reserved. 425972Skarels * 5*33183Sbostic * Redistribution and use in source and binary forms are permitted 6*33183Sbostic * provided that this notice is preserved and that due credit is given 7*33183Sbostic * to the University of California at Berkeley. The name of the University 8*33183Sbostic * may not be used to endorse or promote products derived from this 9*33183Sbostic * software without specific prior written permission. This software 10*33183Sbostic * is provided ``as is'' without express or implied warranty. 11*33183Sbostic * 12*33183Sbostic * @(#)if_arp.h 7.2 (Berkeley) 12/30/87 1325972Skarels */ 1425972Skarels 1525972Skarels /* 1625972Skarels * Address Resolution Protocol. 1725972Skarels * 1825972Skarels * See RFC 826 for protocol description. ARP packets are variable 1925972Skarels * in size; the arphdr structure defines the fixed-length portion. 2025972Skarels * Protocol type values are the same as those for 10 Mb/s Ethernet. 2125972Skarels * It is followed by the variable-sized fields ar_sha, arp_spa, 2225972Skarels * arp_tha and arp_tpa in that order, according to the lengths 2325972Skarels * specified. Field names used correspond to RFC 826. 2425972Skarels */ 2525972Skarels struct arphdr { 2625972Skarels u_short ar_hrd; /* format of hardware address */ 2725972Skarels #define ARPHRD_ETHER 1 /* ethernet hardware address */ 2825972Skarels u_short ar_pro; /* format of protocol address */ 2925972Skarels u_char ar_hln; /* length of hardware address */ 3025972Skarels u_char ar_pln; /* length of protocol address */ 3125972Skarels u_short ar_op; /* one of: */ 3225972Skarels #define ARPOP_REQUEST 1 /* request to resolve address */ 3325972Skarels #define ARPOP_REPLY 2 /* response to previous request */ 3425972Skarels /* 3525972Skarels * The remaining fields are variable in size, 3625972Skarels * according to the sizes above. 3725972Skarels */ 3825972Skarels /* u_char ar_sha[]; /* sender hardware address */ 3925972Skarels /* u_char ar_spa[]; /* sender protocol address */ 4025972Skarels /* u_char ar_tha[]; /* target hardware address */ 4125972Skarels /* u_char ar_tpa[]; /* target protocol address */ 4225972Skarels }; 4325972Skarels 4425972Skarels /* 4525972Skarels * ARP ioctl request 4625972Skarels */ 4725972Skarels struct arpreq { 4825972Skarels struct sockaddr arp_pa; /* protocol address */ 4925972Skarels struct sockaddr arp_ha; /* hardware address */ 5025972Skarels int arp_flags; /* flags */ 5125972Skarels }; 5225972Skarels /* arp_flags and at_flags field values */ 5325972Skarels #define ATF_INUSE 0x01 /* entry in use */ 5425972Skarels #define ATF_COM 0x02 /* completed entry (enaddr valid) */ 5525972Skarels #define ATF_PERM 0x04 /* permanent entry */ 5625972Skarels #define ATF_PUBL 0x08 /* publish entry (respond for other host) */ 5725972Skarels #define ATF_USETRAILERS 0x10 /* has requested trailers */ 58