1/*	$NetBSD: nd.h,v 1.3 2020/09/15 10:05:36 roy Exp $	*/
 2
 3/*
 4 * Copyright (c) 2020 The NetBSD Foundation, Inc.
 5 *
 6 * This code is derived from software contributed to The NetBSD Foundation
 7 * by Roy Marples.
 8 *
 9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 */
29
30#ifndef _NET_ND_H_
31#define _NET_ND_H_
32
33/* ND LLINFO states */
34#define	ND_LLINFO_PURGE		-3
35#define	ND_LLINFO_NOSTATE	-2
36#define	ND_LLINFO_WAITDELETE	-1
37#define	ND_LLINFO_INCOMPLETE	0
38#define	ND_LLINFO_REACHABLE	1
39#define	ND_LLINFO_STALE		2
40#define	ND_LLINFO_DELAY		3
41#define	ND_LLINFO_PROBE		4
42#define	ND_LLINFO_UNREACHABLE	5
43
44#ifdef _KERNEL
45#define	ND_IS_LLINFO_PROBREACH(ln)	\
46	((ln)->ln_state > ND_LLINFO_INCOMPLETE)
47#define	ND_IS_LLINFO_PERMANENT(ln)	\
48	(((ln)->ln_expire == 0) && ((ln)->ln_state > ND_LLINFO_INCOMPLETE))
49
50/* ND timer types */
51#define	ND_TIMER_IMMEDIATE		0
52#define	ND_TIMER_TICK			1
53#define	ND_TIMER_REACHABLE		2
54#define	ND_TIMER_RETRANS		3
55#define	ND_TIMER_RETRANS_BACKOFF	4
56#define	ND_TIMER_EXPIRE			5
57#define	ND_TIMER_DELAY			6
58#define	ND_TIMER_GC			7
59
60/* node constants */
61#define	MAX_REACHABLE_TIME		3600000	/* msec */
62#define	REACHABLE_TIME			30000	/* msec */
63#define	RETRANS_TIMER			1000	/* msec */
64#define	MAX_RETRANS_TIMER		60000	/* msec */
65#define	BACKOFF_MULTIPLE		3
66#define	MIN_RANDOM_FACTOR		512	/* 1024 * 0.5 */
67#define	MAX_RANDOM_FACTOR		1536	/* 1024 * 1.5 */
68#define	ND_COMPUTE_RTIME(x) \
69		((MIN_RANDOM_FACTOR * (x >> 10)) + (cprng_fast32() & \
70		((MAX_RANDOM_FACTOR - MIN_RANDOM_FACTOR) * (x >> 10))))
71
72struct nd_domain {
73	int nd_family;
74	int nd_delay;		/* delay first probe time in seconds */
75	int nd_mmaxtries;	/* maximum multicast query */
76	int nd_umaxtries;	/* maximum unicast query */
77	int nd_retransmultiple;	/* retransmission multiplier for backoff */
78	int nd_maxretrans;	/* maximum retransmission time in msec */
79	int nd_maxnudhint;	/* max # of subsequent upper layer hints */
80	int nd_maxqueuelen;	/* max # of packets in unresolved ND entries */
81	bool (*nd_nud_enabled)(struct ifnet *);
82	unsigned int (*nd_reachable)(struct ifnet *);	/* msec */
83	unsigned int (*nd_retrans)(struct ifnet *);	/* msec */
84	union l3addr *(*nd_holdsrc)(struct llentry *, union l3addr *);
85	void (*nd_output)(struct ifnet *, const union l3addr *,
86	    const union l3addr *, const uint8_t *, const union l3addr *);
87	void (*nd_missed)(struct ifnet *, const union l3addr *,
88	    int16_t, struct mbuf *);
89	void (*nd_free)(struct llentry *, int);
90};
91
92int nd_resolve(struct llentry *, const struct rtentry *, struct mbuf *,
93    uint8_t *, size_t);
94void nd_set_timer(struct llentry *, int);
95void nd_nud_hint(struct llentry *);
96
97void nd_attach_domain(struct nd_domain *);
98#endif /* !_KERNEL */
99#endif /* !_NET_ND_H_ */