xref: /freebsd/usr.sbin/rtadvd/timer.c (revision 0b57cec536236d46e3dba9bd041533462f33dbb7)
1 /*	$FreeBSD$	*/
2 /*	$KAME: timer.c,v 1.9 2002/06/10 19:59:47 itojun Exp $	*/
3 
4 /*-
5  * SPDX-License-Identifier: BSD-3-Clause
6  *
7  * Copyright (C) 1998 WIDE Project.
8  * Copyright (C) 2011 Hiroki Sato <hrs@FreeBSD.org>
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. Neither the name of the project nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/queue.h>
37 #include <sys/socket.h>
38 
39 #include <net/if.h>
40 #include <net/if_dl.h>
41 #include <netinet/in.h>
42 
43 #include <unistd.h>
44 #include <syslog.h>
45 #include <stdlib.h>
46 #include <string.h>
47 #include <search.h>
48 #include <time.h>
49 #include <netdb.h>
50 
51 #include "rtadvd.h"
52 #include "timer_subr.h"
53 #include "timer.h"
54 
55 struct rtadvd_timer_head_t ra_timer =
56     TAILQ_HEAD_INITIALIZER(ra_timer);
57 static struct timespec tm_limit;
58 static struct timespec tm_max;
59 
60 void
61 rtadvd_timer_init(void)
62 {
63 	/* Generate maximum time in timespec. */
64 	tm_limit.tv_sec = (-1) & ~((time_t)1 << ((sizeof(tm_max.tv_sec) * 8) - 1));
65 	tm_limit.tv_nsec = (-1) & ~((long)1 << ((sizeof(tm_max.tv_nsec) * 8) - 1));
66 	tm_max = tm_limit;
67 	TAILQ_INIT(&ra_timer);
68 }
69 
70 void
71 rtadvd_update_timeout_handler(void)
72 {
73 	struct ifinfo *ifi;
74 
75 	TAILQ_FOREACH(ifi, &ifilist, ifi_next) {
76 		switch (ifi->ifi_state) {
77 		case IFI_STATE_CONFIGURED:
78 		case IFI_STATE_TRANSITIVE:
79 			if (ifi->ifi_ra_timer != NULL)
80 				continue;
81 
82 			syslog(LOG_DEBUG, "<%s> add timer for %s (idx=%d)",
83 			    __func__, ifi->ifi_ifname, ifi->ifi_ifindex);
84 			ifi->ifi_ra_timer = rtadvd_add_timer(ra_timeout,
85 			    ra_timer_update, ifi, ifi);
86 			ra_timer_update((void *)ifi,
87 			    &ifi->ifi_ra_timer->rat_tm);
88 			rtadvd_set_timer(&ifi->ifi_ra_timer->rat_tm,
89 			    ifi->ifi_ra_timer);
90 			break;
91 		case IFI_STATE_UNCONFIGURED:
92 			if (ifi->ifi_ra_timer == NULL)
93 				continue;
94 
95 			syslog(LOG_DEBUG,
96 			    "<%s> remove timer for %s (idx=%d)", __func__,
97 			    ifi->ifi_ifname, ifi->ifi_ifindex);
98 			rtadvd_remove_timer(ifi->ifi_ra_timer);
99 			ifi->ifi_ra_timer = NULL;
100 			break;
101 		}
102 	}
103 
104 	return;
105 }
106 
107 struct rtadvd_timer *
108 rtadvd_add_timer(struct rtadvd_timer *(*timeout)(void *),
109     void (*update)(void *, struct timespec *),
110     void *timeodata, void *updatedata)
111 {
112 	struct rtadvd_timer *rat;
113 
114 	if (timeout == NULL) {
115 		syslog(LOG_ERR,
116 		    "<%s> timeout function unspecified", __func__);
117 		exit(1);
118 	}
119 
120 	rat = malloc(sizeof(*rat));
121 	if (rat == NULL) {
122 		syslog(LOG_ERR,
123 		    "<%s> can't allocate memory", __func__);
124 		exit(1);
125 	}
126 	memset(rat, 0, sizeof(*rat));
127 
128 	rat->rat_expire = timeout;
129 	rat->rat_update = update;
130 	rat->rat_expire_data = timeodata;
131 	rat->rat_update_data = updatedata;
132 	rat->rat_tm = tm_max;
133 
134 	/* link into chain */
135 	TAILQ_INSERT_TAIL(&ra_timer, rat, rat_next);
136 
137 	return (rat);
138 }
139 
140 void
141 rtadvd_remove_timer(struct rtadvd_timer *rat)
142 {
143 
144 	if (rat == NULL)
145 		return;
146 
147 	TAILQ_REMOVE(&ra_timer, rat, rat_next);
148 	free(rat);
149 }
150 
151 /*
152  * Check expiration for each timer. If a timer expires,
153  * call the expire function for the timer and update the timer.
154  * Return the next interval for select() call.
155  */
156 struct timespec *
157 rtadvd_check_timer(void)
158 {
159 	static struct timespec returnval;
160 	struct timespec now;
161 	struct rtadvd_timer *rat;
162 
163 	clock_gettime(CLOCK_MONOTONIC_FAST, &now);
164 	tm_max = tm_limit;
165 	TAILQ_FOREACH(rat, &ra_timer, rat_next) {
166 		if (TS_CMP(&rat->rat_tm, &now, <=)) {
167 			if (((*rat->rat_expire)(rat->rat_expire_data) == NULL))
168 				continue; /* the timer was removed */
169 			if (rat->rat_update)
170 				(*rat->rat_update)(rat->rat_update_data, &rat->rat_tm);
171 			TS_ADD(&rat->rat_tm, &now, &rat->rat_tm);
172 		}
173 		if (TS_CMP(&rat->rat_tm, &tm_max, <))
174 			tm_max = rat->rat_tm;
175 	}
176 	if (TS_CMP(&tm_max, &tm_limit, ==)) {
177 		/* no need to timeout */
178 		return (NULL);
179 	} else if (TS_CMP(&tm_max, &now, <)) {
180 		/* this may occur when the interval is too small */
181 		returnval.tv_sec = returnval.tv_nsec = 0;
182 	} else
183 		TS_SUB(&tm_max, &now, &returnval);
184 	return (&returnval);
185 }
186 
187 void
188 rtadvd_set_timer(struct timespec *tm, struct rtadvd_timer *rat)
189 {
190 	struct timespec now;
191 
192 	/* reset the timer */
193 	clock_gettime(CLOCK_MONOTONIC_FAST, &now);
194 	TS_ADD(&now, tm, &rat->rat_tm);
195 
196 	/* update the next expiration time */
197 	if (TS_CMP(&rat->rat_tm, &tm_max, <))
198 		tm_max = rat->rat_tm;
199 
200 	return;
201 }
202