xref: /freebsd/usr.sbin/rtadvd/timer.c (revision 4e579ad047720775ab580b74192c7de8a3386fea)
1 /*	$KAME: timer.c,v 1.9 2002/06/10 19:59:47 itojun Exp $	*/
2 
3 /*-
4  * SPDX-License-Identifier: BSD-3-Clause
5  *
6  * Copyright (C) 1998 WIDE Project.
7  * Copyright (C) 2011 Hiroki Sato <hrs@FreeBSD.org>
8  * All rights reserved.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the project nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #include <sys/queue.h>
36 #include <sys/socket.h>
37 
38 #include <net/if.h>
39 #include <net/if_dl.h>
40 #include <netinet/in.h>
41 
42 #include <unistd.h>
43 #include <syslog.h>
44 #include <stdlib.h>
45 #include <string.h>
46 #include <search.h>
47 #include <time.h>
48 #include <netdb.h>
49 
50 #include "rtadvd.h"
51 #include "timer_subr.h"
52 #include "timer.h"
53 
54 struct rtadvd_timer_head_t ra_timer =
55     TAILQ_HEAD_INITIALIZER(ra_timer);
56 static struct timespec tm_limit;
57 static struct timespec tm_max;
58 
59 void
60 rtadvd_timer_init(void)
61 {
62 	/* Generate maximum time in timespec. */
63 	tm_limit.tv_sec = (-1) & ~((time_t)1 << ((sizeof(tm_max.tv_sec) * 8) - 1));
64 	tm_limit.tv_nsec = (-1) & ~((long)1 << ((sizeof(tm_max.tv_nsec) * 8) - 1));
65 	tm_max = tm_limit;
66 	TAILQ_INIT(&ra_timer);
67 }
68 
69 void
70 rtadvd_update_timeout_handler(void)
71 {
72 	struct ifinfo *ifi;
73 
74 	TAILQ_FOREACH(ifi, &ifilist, ifi_next) {
75 		switch (ifi->ifi_state) {
76 		case IFI_STATE_CONFIGURED:
77 		case IFI_STATE_TRANSITIVE:
78 			if (ifi->ifi_ra_timer != NULL)
79 				continue;
80 
81 			syslog(LOG_DEBUG, "<%s> add timer for %s (idx=%d)",
82 			    __func__, ifi->ifi_ifname, ifi->ifi_ifindex);
83 			ifi->ifi_ra_timer = rtadvd_add_timer(ra_timeout,
84 			    ra_timer_update, ifi, ifi);
85 			ra_timer_update((void *)ifi,
86 			    &ifi->ifi_ra_timer->rat_tm);
87 			rtadvd_set_timer(&ifi->ifi_ra_timer->rat_tm,
88 			    ifi->ifi_ra_timer);
89 			break;
90 		case IFI_STATE_UNCONFIGURED:
91 			if (ifi->ifi_ra_timer == NULL)
92 				continue;
93 
94 			syslog(LOG_DEBUG,
95 			    "<%s> remove timer for %s (idx=%d)", __func__,
96 			    ifi->ifi_ifname, ifi->ifi_ifindex);
97 			rtadvd_remove_timer(ifi->ifi_ra_timer);
98 			ifi->ifi_ra_timer = NULL;
99 			break;
100 		}
101 	}
102 
103 	return;
104 }
105 
106 struct rtadvd_timer *
107 rtadvd_add_timer(struct rtadvd_timer *(*timeout)(void *),
108     void (*update)(void *, struct timespec *),
109     void *timeodata, void *updatedata)
110 {
111 	struct rtadvd_timer *rat;
112 
113 	if (timeout == NULL) {
114 		syslog(LOG_ERR,
115 		    "<%s> timeout function unspecified", __func__);
116 		exit(1);
117 	}
118 
119 	rat = malloc(sizeof(*rat));
120 	if (rat == NULL) {
121 		syslog(LOG_ERR,
122 		    "<%s> can't allocate memory", __func__);
123 		exit(1);
124 	}
125 	memset(rat, 0, sizeof(*rat));
126 
127 	rat->rat_expire = timeout;
128 	rat->rat_update = update;
129 	rat->rat_expire_data = timeodata;
130 	rat->rat_update_data = updatedata;
131 	rat->rat_tm = tm_max;
132 
133 	/* link into chain */
134 	TAILQ_INSERT_TAIL(&ra_timer, rat, rat_next);
135 
136 	return (rat);
137 }
138 
139 void
140 rtadvd_remove_timer(struct rtadvd_timer *rat)
141 {
142 
143 	if (rat == NULL)
144 		return;
145 
146 	TAILQ_REMOVE(&ra_timer, rat, rat_next);
147 	free(rat);
148 }
149 
150 /*
151  * Check expiration for each timer. If a timer expires,
152  * call the expire function for the timer and update the timer.
153  * Return the next interval for select() call.
154  */
155 struct timespec *
156 rtadvd_check_timer(void)
157 {
158 	static struct timespec returnval;
159 	struct timespec now;
160 	struct rtadvd_timer *rat;
161 
162 	clock_gettime(CLOCK_MONOTONIC_FAST, &now);
163 	tm_max = tm_limit;
164 	TAILQ_FOREACH(rat, &ra_timer, rat_next) {
165 		if (TS_CMP(&rat->rat_tm, &now, <=)) {
166 			if (((*rat->rat_expire)(rat->rat_expire_data) == NULL))
167 				continue; /* the timer was removed */
168 			if (rat->rat_update)
169 				(*rat->rat_update)(rat->rat_update_data, &rat->rat_tm);
170 			TS_ADD(&rat->rat_tm, &now, &rat->rat_tm);
171 		}
172 		if (TS_CMP(&rat->rat_tm, &tm_max, <))
173 			tm_max = rat->rat_tm;
174 	}
175 	if (TS_CMP(&tm_max, &tm_limit, ==)) {
176 		/* no need to timeout */
177 		return (NULL);
178 	} else if (TS_CMP(&tm_max, &now, <)) {
179 		/* this may occur when the interval is too small */
180 		returnval.tv_sec = returnval.tv_nsec = 0;
181 	} else
182 		TS_SUB(&tm_max, &now, &returnval);
183 	return (&returnval);
184 }
185 
186 void
187 rtadvd_set_timer(struct timespec *tm, struct rtadvd_timer *rat)
188 {
189 	struct timespec now;
190 
191 	/* reset the timer */
192 	clock_gettime(CLOCK_MONOTONIC_FAST, &now);
193 	TS_ADD(&now, tm, &rat->rat_tm);
194 
195 	/* update the next expiration time */
196 	if (TS_CMP(&rat->rat_tm, &tm_max, <))
197 		tm_max = rat->rat_tm;
198 
199 	return;
200 }
201