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 
72 struct 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 
92 int nd_resolve(struct llentry *, const struct rtentry *, struct mbuf *,
93     uint8_t *, size_t);
94 void nd_set_timer(struct llentry *, int);
95 void nd_nud_hint(struct llentry *);
96 
97 void nd_attach_domain(struct nd_domain *);
98 #endif /* !_KERNEL */
99 #endif /* !_NET_ND_H_ */
100