1 /* $NetBSD: if_arp.h,v 1.43 2021/02/19 14:51:59 christos 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. 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 * @(#)if_arp.h 8.1 (Berkeley) 6/10/93
32 */
33
34 #ifndef _NET_IF_ARP_H_
35 #define _NET_IF_ARP_H_
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 uint16_t ar_hrd; /* format of hardware address */
48 #define ARPHRD_ETHER 1 /* ethernet hardware format */
49 #define ARPHRD_IEEE802 6 /* IEEE 802 hardware format */
50 #define ARPHRD_ARCNET 7 /* ethernet hardware format */
51 #define ARPHRD_FRELAY 15 /* frame relay hardware format */
52 #define ARPHRD_STRIP 23 /* Ricochet Starmode Radio hardware format */
53 #define ARPHRD_IEEE1394 24 /* IEEE 1394 (FireWire) hardware format */
54 uint16_t ar_pro; /* format of protocol address */
55 uint8_t ar_hln; /* length of hardware address */
56 uint8_t ar_pln; /* length of protocol address */
57 uint16_t ar_op; /* one of: */
58 #define ARPOP_REQUEST 1 /* request to resolve address */
59 #define ARPOP_REPLY 2 /* response to previous request */
60 #define ARPOP_REVREQUEST 3 /* request protocol address given hardware */
61 #define ARPOP_REVREPLY 4 /* response giving protocol address */
62 #define ARPOP_INVREQUEST 8 /* request to identify peer */
63 #define ARPOP_INVREPLY 9 /* response identifying peer */
64 /*
65 * The remaining fields are variable in size,
66 * according to the sizes above.
67 */
68 #ifdef COMMENT_ONLY
69 uint8_t ar_sha[]; /* sender hardware address */
70 uint8_t ar_spa[]; /* sender protocol address */
71 uint8_t ar_tha[]; /* target hardware address (!IEEE1394) */
72 uint8_t ar_tpa[]; /* target protocol address */
73 #endif
74 };
75
76 static __inline uint8_t *
ar_data(struct arphdr * ap)77 ar_data(struct arphdr *ap)
78 {
79 return (uint8_t *)(void *)(ap + 1);
80 }
81
82 static __inline uint8_t *
ar_sha(struct arphdr * ap)83 ar_sha(struct arphdr *ap)
84 {
85 return ar_data(ap) + 0;
86 }
87
88 static __inline uint8_t *
ar_spa(struct arphdr * ap)89 ar_spa(struct arphdr *ap)
90 {
91 return ar_data(ap) + ap->ar_hln;
92 }
93
94 static __inline uint8_t *
ar_tha(struct arphdr * ap)95 ar_tha(struct arphdr *ap)
96 {
97 if (ntohs(ap->ar_hrd) == ARPHRD_IEEE1394) {
98 return NULL;
99 } else {
100 return ar_data(ap) + ap->ar_hln + ap->ar_pln;
101 }
102 }
103
104 static __inline uint8_t *
ar_tpa(struct arphdr * ap)105 ar_tpa(struct arphdr *ap)
106 {
107 if (ntohs(ap->ar_hrd) == ARPHRD_IEEE1394) {
108 return ar_data(ap) + ap->ar_hln + ap->ar_pln;
109 } else {
110 return ar_data(ap) + ap->ar_hln + ap->ar_pln + ap->ar_hln;
111 }
112 }
113
114 /*
115 * ARP ioctl request
116 */
117 struct arpreq {
118 struct sockaddr arp_pa; /* protocol address */
119 struct sockaddr arp_ha; /* hardware address */
120 int arp_flags; /* flags */
121 };
122 /* arp_flags and at_flags field values */
123 #define ATF_INUSE 0x01 /* entry in use */
124 #define ATF_COM 0x02 /* completed entry (enaddr valid) */
125 #define ATF_PERM 0x04 /* permanent entry */
126 #define ATF_PUBL 0x08 /* publish entry (respond for other host) */
127 #define ATF_USETRAILERS 0x10 /* has requested trailers */
128
129 /*
130 * Kernel statistics about arp
131 */
132 #define ARP_STAT_SNDTOTAL 0 /* total packets sent */
133 #define ARP_STAT_SNDREPLY 1 /* replies sent */
134 #define ARP_STAT_SENDREQUEST 2 /* requests sent */
135 #define ARP_STAT_RCVTOTAL 3 /* total packets received */
136 #define ARP_STAT_RCVREQUEST 4 /* valid requests received */
137 #define ARP_STAT_RCVREPLY 5 /* replies received */
138 #define ARP_STAT_RCVMCAST 6 /* multicast/broadcast received */
139 #define ARP_STAT_RCVBADPROTO 7 /* unknown protocol type received */
140 #define ARP_STAT_RCVBADLEN 8 /* bad (short) length received */
141 #define ARP_STAT_RCVZEROTPA 9 /* received w/ null target ip */
142 #define ARP_STAT_RCVZEROSPA 10 /* received w/ null source ip */
143 #define ARP_STAT_RCVNOINT 11 /* couldn't map to interface */
144 #define ARP_STAT_RCVLOCALSHA 12 /* received from local hw address */
145 #define ARP_STAT_RCVBCASTSHA 13 /* received w/ broadcast src */
146 #define ARP_STAT_RCVLOCALSPA 14 /* received for a local ip [dup!] */
147 #define ARP_STAT_RCVOVERPERM 15 /* attempts to overwrite static info */
148 #define ARP_STAT_RCVOVERINT 16 /* attempts to overwrite wrong if */
149 #define ARP_STAT_RCVOVER 17 /* entries overwritten! */
150 #define ARP_STAT_RCVLENCHG 18 /* changes in hw address len */
151 #define ARP_STAT_DFRTOTAL 19 /* deferred pending ARP resolution */
152 #define ARP_STAT_DFRSENT 20 /* deferred, then sent */
153 #define ARP_STAT_DFRDROPPED 21 /* deferred, then dropped */
154 #define ARP_STAT_ALLOCFAIL 22 /* failures to allocate llinfo */
155
156 #define ARP_NSTATS 23
157
158 void arp_stat_add(int, uint64_t);
159
160 #endif /* !_NET_IF_ARP_H_ */
161