usr.sbin/rtadvd/timer.c

   1 /*      $FreeBSD: stable/10/usr.sbin/rtadvd/timer.c 253995 2013-08-06 15:49:18Z hrs $   */
   2 /*      $KAME: timer.c,v 1.9 2002/06/10 19:59:47 itojun Exp $   */
   3
   4 /*
   5  * Copyright (C) 1998 WIDE Project.
   6  * Copyright (C) 2011 Hiroki Sato <hrs@FreeBSD.org>
   7  * All rights reserved.
   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  * 3. Neither the name of the project nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #include <sys/queue.h>
  35 #include <sys/socket.h>
  36
  37 #include <net/if.h>
  38 #include <net/if_dl.h>
  39 #include <netinet/in.h>
  40
  41 #include <unistd.h>
  42 #include <syslog.h>
  43 #include <stdlib.h>
  44 #include <string.h>
  45 #include <search.h>
  46 #include <time.h>
  47 #include <netdb.h>
  48
  49 #include "rtadvd.h"
  50 #include "timer_subr.h"
  51 #include "timer.h"
  52
  53 struct rtadvd_timer_head_t ra_timer =
  54     TAILQ_HEAD_INITIALIZER(ra_timer);
  55 static struct timespec tm_limit;
  56 static struct timespec tm_max;
  57
  58 void
  59 rtadvd_timer_init(void)
  60 {
  61         /* Generate maximum time in timespec. */
  62         tm_limit.tv_sec = (-1) & ~((time_t)1 << ((sizeof(tm_max.tv_sec) * 8) - 1));
  63         tm_limit.tv_nsec = (-1) & ~((long)1 << ((sizeof(tm_max.tv_nsec) * 8) - 1));
  64         tm_max = tm_limit;
  65         TAILQ_INIT(&ra_timer);
  66 }
  67
  68 void
  69 rtadvd_update_timeout_handler(void)
  70 {
  71         struct ifinfo *ifi;
  72
  73         TAILQ_FOREACH(ifi, &ifilist, ifi_next) {
  74                 switch (ifi->ifi_state) {
  75                 case IFI_STATE_CONFIGURED:
  76                 case IFI_STATE_TRANSITIVE:
  77                         if (ifi->ifi_ra_timer != NULL)
  78                                 continue;
  79
  80                         syslog(LOG_DEBUG, "<%s> add timer for %s (idx=%d)",
  81                             __func__, ifi->ifi_ifname, ifi->ifi_ifindex);
  82                         ifi->ifi_ra_timer = rtadvd_add_timer(ra_timeout,
  83                             ra_timer_update, ifi, ifi);
  84                         ra_timer_update((void *)ifi,
  85                             &ifi->ifi_ra_timer->rat_tm);
  86                         rtadvd_set_timer(&ifi->ifi_ra_timer->rat_tm,
  87                             ifi->ifi_ra_timer);
  88                         break;
  89                 case IFI_STATE_UNCONFIGURED:
  90                         if (ifi->ifi_ra_timer == NULL)
  91                                 continue;
  92
  93                         syslog(LOG_DEBUG,
  94                             "<%s> remove timer for %s (idx=%d)", __func__,
  95                             ifi->ifi_ifname, ifi->ifi_ifindex);
  96                         rtadvd_remove_timer(ifi->ifi_ra_timer);
  97                         ifi->ifi_ra_timer = NULL;
  98                         break;
  99                 }
 100         }
 101
 102         return;
 103 }
 104
 105 struct rtadvd_timer *
 106 rtadvd_add_timer(struct rtadvd_timer *(*timeout)(void *),
 107     void (*update)(void *, struct timespec *),
 108     void *timeodata, void *updatedata)
 109 {
 110         struct rtadvd_timer *rat;
 111
 112         if (timeout == NULL) {
 113                 syslog(LOG_ERR,
 114                     "<%s> timeout function unspecified", __func__);
 115                 exit(1);
 116         }
 117
 118         rat = malloc(sizeof(*rat));
 119         if (rat == NULL) {
 120                 syslog(LOG_ERR,
 121                     "<%s> can't allocate memory", __func__);
 122                 exit(1);
 123         }
 124         memset(rat, 0, sizeof(*rat));
 125
 126         rat->rat_expire = timeout;
 127         rat->rat_update = update;
 128         rat->rat_expire_data = timeodata;
 129         rat->rat_update_data = updatedata;
 130         rat->rat_tm = tm_max;
 131
 132         /* link into chain */
 133         TAILQ_INSERT_TAIL(&ra_timer, rat, rat_next);
 134
 135         return (rat);
 136 }
 137
 138 void
 139 rtadvd_remove_timer(struct rtadvd_timer *rat)
 140 {
 141
 142         if (rat == NULL)
 143                 return;
 144
 145         TAILQ_REMOVE(&ra_timer, rat, rat_next);
 146         free(rat);
 147 }
 148
 149 /*
 150  * Check expiration for each timer. If a timer expires,
 151  * call the expire function for the timer and update the timer.
 152  * Return the next interval for select() call.
 153  */
 154 struct timespec *
 155 rtadvd_check_timer(void)
 156 {
 157         static struct timespec returnval;
 158         struct timespec now;
 159         struct rtadvd_timer *rat;
 160
 161         clock_gettime(CLOCK_MONOTONIC_FAST, &now);
 162         tm_max = tm_limit;
 163         TAILQ_FOREACH(rat, &ra_timer, rat_next) {
 164                 if (TS_CMP(&rat->rat_tm, &now, <=)) {
 165                         if (((*rat->rat_expire)(rat->rat_expire_data) == NULL))
 166                                 continue; /* the timer was removed */
 167                         if (rat->rat_update)
 168                                 (*rat->rat_update)(rat->rat_update_data, &rat->rat_tm);
 169                         TS_ADD(&rat->rat_tm, &now, &rat->rat_tm);
 170                 }
 171                 if (TS_CMP(&rat->rat_tm, &tm_max, <))
 172                         tm_max = rat->rat_tm;
 173         }
 174         if (TS_CMP(&tm_max, &tm_limit, ==)) {
 175                 /* no need to timeout */
 176                 return (NULL);
 177         } else if (TS_CMP(&tm_max, &now, <)) {
 178                 /* this may occur when the interval is too small */
 179                 returnval.tv_sec = returnval.tv_nsec = 0;
 180         } else
 181                 TS_SUB(&tm_max, &now, &returnval);
 182         return (&returnval);
 183 }
 184
 185 void
 186 rtadvd_set_timer(struct timespec *tm, struct rtadvd_timer *rat)
 187 {
 188         struct timespec now;
 189
 190         /* reset the timer */
 191         clock_gettime(CLOCK_MONOTONIC_FAST, &now);
 192         TS_ADD(&now, tm, &rat->rat_tm);
 193
 194         /* update the next expiration time */
 195         if (TS_CMP(&rat->rat_tm, &tm_max, <))
 196                 tm_max = rat->rat_tm;
 197
 198         return;
 199 }