if_arp.h revision 128376 
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 * 4. Neither the name of the University nor the names of its contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 *	@(#)if_arp.h	8.1 (Berkeley) 6/10/93
30 * $FreeBSD: head/sys/net/if_arp.h 128376 2004-04-18 01:15:32Z luigi $
31 */
32
33#ifndef _NET_IF_ARP_H_
34#define	_NET_IF_ARP_H_
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 */
46struct	arphdr {
47	u_short	ar_hrd;		/* format of hardware address */
48#define ARPHRD_ETHER 	1	/* ethernet hardware format */
49#define ARPHRD_IEEE802	6	/* token-ring hardware format */
50#define ARPHRD_ARCNET	7	/* arcnet hardware format */
51#define ARPHRD_FRELAY 	15	/* frame relay hardware format */
52	u_short	ar_pro;		/* format of protocol address */
53	u_char	ar_hln;		/* length of hardware address */
54	u_char	ar_pln;		/* length of protocol address */
55	u_short	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_char	ar_sha[];	/* sender hardware address */
68	u_char	ar_spa[];	/* sender protocol address */
69	u_char	ar_tha[];	/* target hardware address */
70	u_char	ar_tpa[];	/* target protocol address */
71#endif
72};
73
74#define ar_sha(ap)	(((caddr_t)((ap)+1)) +   0)
75#define ar_spa(ap)	(((caddr_t)((ap)+1)) +   (ap)->ar_hln)
76#define ar_tha(ap)	(((caddr_t)((ap)+1)) +   (ap)->ar_hln + (ap)->ar_pln)
77#define ar_tpa(ap)	(((caddr_t)((ap)+1)) + 2*(ap)->ar_hln + (ap)->ar_pln)
78
79#define arphdr_len2(ar_hln, ar_pln)					\
80	(sizeof(struct arphdr) + 2*(ar_hln) + 2*(ar_pln))
81#define arphdr_len(ap)	(arphdr_len2((ap)->ar_hln, (ap)->ar_pln))
82
83/*
84 * ARP ioctl request
85 */
86struct arpreq {
87	struct	sockaddr arp_pa;		/* protocol address */
88	struct	sockaddr arp_ha;		/* hardware address */
89	int	arp_flags;			/* flags */
90};
91/*  arp_flags and at_flags field values */
92#define	ATF_INUSE	0x01	/* entry in use */
93#define ATF_COM		0x02	/* completed entry (enaddr valid) */
94#define	ATF_PERM	0x04	/* permanent entry */
95#define	ATF_PUBL	0x08	/* publish entry (respond for other host) */
96#define	ATF_USETRAILERS	0x10	/* has requested trailers */
97
98#ifdef _KERNEL
99/*
100 * Structure shared between the ethernet driver modules and
101 * the address resolution code.  For example, each ec_softc or il_softc
102 * begins with this structure.
103 * The code is written so that each *_softc _must_ begin with a
104 * struct arpcom, which in turn _must_ begin with a struct ifnet.
105 */
106struct	arpcom {
107	/*
108	 * The ifnet struct _must_ be at the head of this structure.
109	 */
110	struct 	ifnet ac_if;		/* network-visible interface */
111	u_char	ac_enaddr[6];		/* ethernet hardware address */
112	int	now_unused;	/* XXX was length of ac_multiaddrs list */
113	void	*ac_netgraph;		/* ng_ether(4) netgraph node info */
114};
115#define IFP2AC(ifp) ((struct arpcom *)(ifp))
116
117#endif
118
119#endif /* !_NET_IF_ARP_H_ */
120