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The C and C++ Include Header Files
cat -n /usr/include/net/if_arp.h
1 /* Definitions for Address Resolution Protocol. 2 Copyright (C) 1997-2026 Free Software Foundation, Inc. 3 This file is part of the GNU C Library. 4 5 The GNU C Library is free software; you can redistribute it and/or 6 modify it under the terms of the GNU Lesser General Public 7 License as published by the Free Software Foundation; either 8 version 2.1 of the License, or (at your option) any later version. 9 10 The GNU C Library is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public 16 License along with the GNU C Library; if not, see 17 <https://www.gnu.org/licenses/>. */ 18 19 /* Based on the 4.4BSD and Linux version of this file. */ 20 21 #ifndef _NET_IF_ARP_H 22 #define _NET_IF_ARP_H 1 23 24 #include <sys/types.h> 25 #include <sys/socket.h> 26 #include <stdint.h> 27 28 __BEGIN_DECLS 29 30 /* Some internals from deep down in the kernel. */ 31 #define MAX_ADDR_LEN 7 32 33 34 /* This structure defines an ethernet arp header. */ 35 36 /* ARP protocol opcodes. */ 37 #define ARPOP_REQUEST 1 /* ARP request. */ 38 #define ARPOP_REPLY 2 /* ARP reply. */ 39 #define ARPOP_RREQUEST 3 /* RARP request. */ 40 #define ARPOP_RREPLY 4 /* RARP reply. */ 41 #define ARPOP_InREQUEST 8 /* InARP request. */ 42 #define ARPOP_InREPLY 9 /* InARP reply. */ 43 #define ARPOP_NAK 10 /* (ATM)ARP NAK. */ 44 45 /* See RFC 826 for protocol description. ARP packets are variable 46 in size; the arphdr structure defines the fixed-length portion. 47 Protocol type values are the same as those for 10 Mb/s Ethernet. 48 It is followed by the variable-sized fields ar_sha, arp_spa, 49 arp_tha and arp_tpa in that order, according to the lengths 50 specified. Field names used correspond to RFC 826. */ 51 52 struct arphdr 53 { 54 unsigned short int ar_hrd; /* Format of hardware address. */ 55 unsigned short int ar_pro; /* Format of protocol address. */ 56 unsigned char ar_hln; /* Length of hardware address. */ 57 unsigned char ar_pln; /* Length of protocol address. */ 58 unsigned short int ar_op; /* ARP opcode (command). */ 59 #if 0 60 /* Ethernet looks like this : This bit is variable sized 61 however... */ 62 unsigned char __ar_sha[ETH_ALEN]; /* Sender hardware address. */ 63 unsigned char __ar_sip[4]; /* Sender IP address. */ 64 unsigned char __ar_tha[ETH_ALEN]; /* Target hardware address. */ 65 unsigned char __ar_tip[4]; /* Target IP address. */ 66 #endif 67 }; 68 69 70 /* ARP protocol HARDWARE identifiers. */ 71 #define ARPHRD_NETROM 0 /* From KA9Q: NET/ROM pseudo. */ 72 #define ARPHRD_ETHER 1 /* Ethernet 10/100Mbps. */ 73 #define ARPHRD_EETHER 2 /* Experimental Ethernet. */ 74 #define ARPHRD_AX25 3 /* AX.25 Level 2. */ 75 #define ARPHRD_PRONET 4 /* PROnet token ring. */ 76 #define ARPHRD_CHAOS 5 /* Chaosnet. */ 77 #define ARPHRD_IEEE802 6 /* IEEE 802.2 Ethernet/TR/TB. */ 78 #define ARPHRD_ARCNET 7 /* ARCnet. */ 79 #define ARPHRD_APPLETLK 8 /* APPLEtalk. */ 80 #define ARPHRD_DLCI 15 /* Frame Relay DLCI. */ 81 #define ARPHRD_ATM 19 /* ATM. */ 82 #define ARPHRD_METRICOM 23 /* Metricom STRIP (new IANA id). */ 83 #define ARPHRD_IEEE1394 24 /* IEEE 1394 IPv4 - RFC 2734. */ 84 #define ARPHRD_EUI64 27 /* EUI-64. */ 85 #define ARPHRD_INFINIBAND 32 /* InfiniBand. */ 86 87 /* Dummy types for non ARP hardware */ 88 #define ARPHRD_SLIP 256 89 #define ARPHRD_CSLIP 257 90 #define ARPHRD_SLIP6 258 91 #define ARPHRD_CSLIP6 259 92 #define ARPHRD_RSRVD 260 /* Notional KISS type. */ 93 #define ARPHRD_ADAPT 264 94 #define ARPHRD_ROSE 270 95 #define ARPHRD_X25 271 /* CCITT X.25. */ 96 #define ARPHRD_HWX25 272 /* Boards with X.25 in firmware. */ 97 #define ARPHRD_CAN 280 /* Controller Area Network. */ 98 #define ARPHRD_MCTP 290 99 #define ARPHRD_PPP 512 100 #define ARPHRD_CISCO 513 /* Cisco HDLC. */ 101 #define ARPHRD_HDLC ARPHRD_CISCO 102 #define ARPHRD_LAPB 516 /* LAPB. */ 103 #define ARPHRD_DDCMP 517 /* Digital's DDCMP. */ 104 #define ARPHRD_RAWHDLC 518 /* Raw HDLC. */ 105 #define ARPHRD_RAWIP 519 /* Raw IP. */ 106 107 #define ARPHRD_TUNNEL 768 /* IPIP tunnel. */ 108 #define ARPHRD_TUNNEL6 769 /* IPIP6 tunnel. */ 109 #define ARPHRD_FRAD 770 /* Frame Relay Access Device. */ 110 #define ARPHRD_SKIP 771 /* SKIP vif. */ 111 #define ARPHRD_LOOPBACK 772 /* Loopback device. */ 112 #define ARPHRD_LOCALTLK 773 /* Localtalk device. */ 113 #define ARPHRD_FDDI 774 /* Fiber Distributed Data Interface. */ 114 #define ARPHRD_BIF 775 /* AP1000 BIF. */ 115 #define ARPHRD_SIT 776 /* sit0 device - IPv6-in-IPv4. */ 116 #define ARPHRD_IPDDP 777 /* IP-in-DDP tunnel. */ 117 #define ARPHRD_IPGRE 778 /* GRE over IP. */ 118 #define ARPHRD_PIMREG 779 /* PIMSM register interface. */ 119 #define ARPHRD_HIPPI 780 /* High Performance Parallel I'face. */ 120 #define ARPHRD_ASH 781 /* (Nexus Electronics) Ash. */ 121 #define ARPHRD_ECONET 782 /* Acorn Econet. */ 122 #define ARPHRD_IRDA 783 /* Linux-IrDA. */ 123 #define ARPHRD_FCPP 784 /* Point to point fibrechanel. */ 124 #define ARPHRD_FCAL 785 /* Fibrechanel arbitrated loop. */ 125 #define ARPHRD_FCPL 786 /* Fibrechanel public loop. */ 126 #define ARPHRD_FCFABRIC 787 /* Fibrechanel fabric. */ 127 #define ARPHRD_IEEE802_TR 800 /* Magic type ident for TR. */ 128 #define ARPHRD_IEEE80211 801 /* IEEE 802.11. */ 129 #define ARPHRD_IEEE80211_PRISM 802 /* IEEE 802.11 + Prism2 header. */ 130 #define ARPHRD_IEEE80211_RADIOTAP 803 /* IEEE 802.11 + radiotap header. */ 131 #define ARPHRD_IEEE802154 804 /* IEEE 802.15.4 header. */ 132 #define ARPHRD_IEEE802154_PHY 805 /* IEEE 802.15.4 PHY header. */ 133 134 #define ARPHRD_VOID 0xFFFF /* Void type, nothing is known. */ 135 #define ARPHRD_NONE 0xFFFE /* Zero header length. */ 136 137 138 /* ARP ioctl request. */ 139 struct arpreq 140 { 141 struct sockaddr arp_pa; /* Protocol address. */ 142 struct sockaddr arp_ha; /* Hardware address. */ 143 int arp_flags; /* Flags. */ 144 struct sockaddr arp_netmask; /* Netmask (only for proxy arps). */ 145 char arp_dev[16]; 146 }; 147 148 struct arpreq_old 149 { 150 struct sockaddr arp_pa; /* Protocol address. */ 151 struct sockaddr arp_ha; /* Hardware address. */ 152 int arp_flags; /* Flags. */ 153 struct sockaddr arp_netmask; /* Netmask (only for proxy arps). */ 154 }; 155 156 /* ARP Flag values. */ 157 #define ATF_COM 0x02 /* Completed entry (ha valid). */ 158 #define ATF_PERM 0x04 /* Permanent entry. */ 159 #define ATF_PUBL 0x08 /* Publish entry. */ 160 #define ATF_USETRAILERS 0x10 /* Has requested trailers. */ 161 #define ATF_NETMASK 0x20 /* Want to use a netmask (only 162 for proxy entries). */ 163 #define ATF_DONTPUB 0x40 /* Don't answer this addresses. */ 164 #define ATF_MAGIC 0x80 /* Automatically added entry. */ 165 166 167 /* Support for the user space arp daemon, arpd. */ 168 #define ARPD_UPDATE 0x01 169 #define ARPD_LOOKUP 0x02 170 #define ARPD_FLUSH 0x03 171 172 struct arpd_request 173 { 174 unsigned short int req; /* Request type. */ 175 uint32_t ip; /* IP address of entry. */ 176 unsigned long int dev; /* Device entry is tied to. */ 177 unsigned long int stamp; 178 unsigned long int updated; 179 unsigned char ha[MAX_ADDR_LEN]; /* Hardware address. */ 180 }; 181 182 __END_DECLS 183 184 #endif /* net/if_arp.h */
