NetBSD/sbin/wdogctl/wdogctl.c

459 lines
11 KiB
C

/* $NetBSD: wdogctl.c,v 1.20 2011/08/27 19:00:35 joerg Exp $ */
/*-
* Copyright (c) 2000 Zembu Labs, Inc.
* All rights reserved.
*
* Author: Jason R. Thorpe <thorpej@zembu.com>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Zembu Labs, Inc.
* 4. Neither the name of Zembu Labs nor the names of its employees may
* be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY ZEMBU LABS, INC. ``AS IS'' AND ANY EXPRESS
* OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WAR-
* RANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DIS-
* CLAIMED. IN NO EVENT SHALL ZEMBU LABS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
#ifndef lint
__RCSID("$NetBSD: wdogctl.c,v 1.20 2011/08/27 19:00:35 joerg Exp $");
#endif
#include <sys/param.h>
#include <sys/ioctl.h>
#include <sys/wdog.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <signal.h>
#include <syslog.h>
#include <unistd.h>
#include <string.h>
#define _PATH_WATCHDOG "/dev/watchdog"
static void enable_kernel(const char *, u_int);
static void enable_user(const char *, u_int, int);
static void enable_ext(const char *, u_int);
static void tickle_ext(void);
static void disable(void);
static void prep_wmode(struct wdog_mode *, int, const char *, u_int);
static void list_timers(void);
__dead static void usage(void);
static int Aflag;
/* Caution -- ordered list; entries >= CMD_EXT_TICKLE set timers */
enum cmd {
CMD_NONE, /* No verb given */
CMD_DISABLE,
CMD_DOTICKLE,
CMD_EXT_TICKLE,
CMD_KERN_TICKLE,
CMD_NOCANCEL_TICKLE,
CMD_USER_TICKLE
};
int
main(int argc, char *argv[])
{
enum cmd command = CMD_NONE;
int period_flag = 0;
int ch, tmp;
u_int period = WDOG_PERIOD_DEFAULT;
while ((ch = getopt(argc, argv, "Adekp:utx")) != -1) {
switch (ch) {
case 'A':
Aflag = 1;
break;
case 'd':
if (command != CMD_NONE)
usage();
command = CMD_DISABLE;
break;
case 'e':
if (command != CMD_NONE)
usage();
command = CMD_EXT_TICKLE;
break;
case 'k':
if (command != CMD_NONE)
usage();
command = CMD_KERN_TICKLE;
break;
case 't':
if (command != CMD_NONE)
usage();
command = CMD_DOTICKLE;
break;
case 'p':
period_flag = 1;
tmp = atoi(optarg);
if (tmp < 0)
usage();
period = (unsigned int)tmp;
break;
case 'x':
case 'u':
if (command != CMD_NONE)
usage();
command =
(ch == 'u') ? CMD_USER_TICKLE : CMD_NOCANCEL_TICKLE;
break;
default:
usage();
}
}
argc -= optind;
argv += optind;
if (command < CMD_EXT_TICKLE) {
if (Aflag || period_flag)
usage();
if (argc != 0)
usage();
} else if (argc != 1)
usage();
switch (command) {
case CMD_NONE:
list_timers();
break;
case CMD_DISABLE:
disable();
break;
case CMD_DOTICKLE:
tickle_ext();
break;
case CMD_EXT_TICKLE:
enable_ext(argv[0], period);
break;
case CMD_KERN_TICKLE:
enable_kernel(argv[0], period);
break;
case CMD_NOCANCEL_TICKLE:
case CMD_USER_TICKLE:
enable_user(argv[0], period, command == CMD_USER_TICKLE);
break;
}
exit(EXIT_SUCCESS);
}
static void
prep_wmode(struct wdog_mode *wp, int mode, const char *name, u_int period)
{
if (strlen(name) >= WDOG_NAMESIZE)
errx(EXIT_FAILURE, "invalid watchdog timer name: %s", name);
strlcpy(wp->wm_name, name, sizeof(wp->wm_name));
wp->wm_mode = mode;
wp->wm_period = period;
if (Aflag)
wp->wm_mode |= WDOG_FEATURE_ALARM;
}
static void
enable_kernel(const char *name, u_int period)
{
struct wdog_mode wm;
int fd;
prep_wmode(&wm, WDOG_MODE_KTICKLE, name, period);
fd = open(_PATH_WATCHDOG, O_RDWR, 0644);
if (fd == -1)
err(EXIT_FAILURE, "open %s", _PATH_WATCHDOG);
if (ioctl(fd, WDOGIOC_SMODE, &wm) == -1)
err(EXIT_FAILURE, "WDOGIOC_SMODE");
(void)close(fd);
}
static void
enable_ext(const char *name, u_int period)
{
struct wdog_mode wm;
int fd;
prep_wmode(&wm, WDOG_MODE_ETICKLE, name, period);
fd = open(_PATH_WATCHDOG, O_RDWR, 0644);
if (fd == -1)
err(EXIT_FAILURE, "open %s", _PATH_WATCHDOG);
if (ioctl(fd, WDOGIOC_SMODE, &wm) == -1) {
err(EXIT_FAILURE, "WDOGIOC_SMODE");
}
if (ioctl(fd, WDOGIOC_TICKLE) == -1)
syslog(LOG_EMERG, "unable to tickle watchdog timer %s: %m",
wm.wm_name);
(void)close(fd);
return;
}
static void
enable_user(const char *name, u_int period, int cancel_on_close)
{
struct wdog_mode wm;
struct timespec ts;
pid_t tickler;
int fd, rv;
prep_wmode(&wm,
(cancel_on_close) ? WDOG_MODE_UTICKLE : WDOG_MODE_ETICKLE, name,
period);
fd = open(_PATH_WATCHDOG, O_RDWR, 0644);
if (fd == -1)
err(EXIT_FAILURE, "open %s", _PATH_WATCHDOG);
/* ...so we can log failures to tickle the timer. */
openlog("wdogctl", LOG_PERROR|LOG_PID, LOG_DAEMON);
/*
* We fork a child process which detaches from the controlling
* terminal once the timer is armed, and tickles the timer
* until we send it a SIGTERM.
*/
tickler = fork();
if (tickler == -1)
err(EXIT_FAILURE, "unable to fork tickler process");
else if (tickler != 0) {
if (ioctl(fd, WDOGIOC_SMODE, &wm) == -1) {
(void)kill(tickler, SIGTERM);
err(EXIT_FAILURE, "WDOGIOC_SMODE");
}
(void)close(fd);
return;
}
/*
* Wait for the watchdog to be armed. When it is, loop,
* tickling the timer, then waiting 1/2 the period before
* doing it again.
*
* If the parent fails to enable the watchdog, it will kill
* us.
*/
do {
rv = ioctl(fd, WDOGIOC_WHICH, &wm);
} while (rv == -1);
if (ioctl(fd, WDOGIOC_TICKLE) == -1)
syslog(LOG_EMERG, "unable to tickle watchdog timer %s: %m",
wm.wm_name);
/*
* Now detach from the controlling terminal, and just run
* in the background. The kernel will keep track of who
* we are, each time we tickle the timer.
*/
if (daemon(0, 0) == -1) {
/*
* We weren't able to go into the background. When
* we exit, the kernel will disable the watchdog so
* that the system won't die.
*/
err(EXIT_FAILURE, "unable to detach from terminal");
}
if (ioctl(fd, WDOGIOC_TICKLE) == -1)
syslog(LOG_EMERG, "unable to tickle watchdog timer %s: %m",
wm.wm_name);
for (;;) {
ts.tv_sec = wm.wm_period / 2;
ts.tv_nsec = 0;
(void)nanosleep(&ts, NULL);
if (ioctl(fd, WDOGIOC_TICKLE) == -1)
syslog(LOG_EMERG,
"unable to tickle watchdog timer %s: %m",
wm.wm_name);
}
/* NOTREACHED */
}
static void
tickle_ext(void)
{
int fd;
fd = open(_PATH_WATCHDOG, O_RDWR, 0644);
if (fd == -1)
err(EXIT_FAILURE, "open %s", _PATH_WATCHDOG);
if (ioctl(fd, WDOGIOC_TICKLE) == -1)
fprintf(stderr, "Cannot tickle timer\n");
(void)close(fd);
}
static void
disable(void)
{
struct wdog_mode wm;
pid_t tickler;
int fd, mode;
fd = open(_PATH_WATCHDOG, O_RDWR, 0644);
if (fd == -1)
err(EXIT_FAILURE, "open %s", _PATH_WATCHDOG);
if (ioctl(fd, WDOGIOC_WHICH, &wm) == -1) {
printf("No watchdog timer running.\n");
(void)close(fd);
return;
}
mode = wm.wm_mode & WDOG_MODE_MASK;
/*
* If the timer is running in UTICKLE mode, we need
* to kill the wdogctl(8) process that is tickling
* the timer.
*/
if (mode == WDOG_MODE_UTICKLE) {
if (ioctl(fd, WDOGIOC_GTICKLER, &tickler) == -1)
err(EXIT_FAILURE, "WDOGIOC_GTICKLER");
(void)close(fd);
(void)kill(tickler, SIGTERM);
} else {
wm.wm_mode = WDOG_MODE_DISARMED;
if (ioctl(fd, WDOGIOC_SMODE, &wm) == -1) {
err(EXIT_FAILURE, "unable to disarm watchdog %s",
wm.wm_name);
}
(void)close(fd);
}
}
static void
list_timers(void)
{
struct wdog_conf wc;
struct wdog_mode wm;
char *buf, *cp;
int fd, count, i, mode;
pid_t tickler;
fd = open(_PATH_WATCHDOG, O_RDONLY, 0644);
if (fd == -1)
err(EXIT_FAILURE, "open %s", _PATH_WATCHDOG);
wc.wc_names = NULL;
wc.wc_count = 0;
if (ioctl(fd, WDOGIOC_GWDOGS, &wc) == -1)
err(EXIT_FAILURE, "ioctl WDOGIOC_GWDOGS for count");
count = wc.wc_count;
if (count == 0) {
printf("No watchdog timers present.\n");
goto out;
}
buf = malloc(count * WDOG_NAMESIZE);
if (buf == NULL)
err(EXIT_FAILURE, "malloc %d byte for watchdog names",
count * WDOG_NAMESIZE);
wc.wc_names = buf;
if (ioctl(fd, WDOGIOC_GWDOGS, &wc) == -1)
err(EXIT_FAILURE, "ioctl WDOGIOC_GWDOGS for names");
count = wc.wc_count;
if (count == 0) {
printf("No watchdog timers present.\n");
free(buf);
goto out;
}
printf("Available watchdog timers:\n");
for (i = 0, cp = buf; i < count; i++, cp += WDOG_NAMESIZE) {
cp[WDOG_NAMESIZE - 1] = '\0';
strlcpy(wm.wm_name, cp, sizeof(wm.wm_name));
if (ioctl(fd, WDOGIOC_GMODE, &wm) == -1)
continue;
mode = wm.wm_mode & WDOG_MODE_MASK;
if (mode == WDOG_MODE_UTICKLE) {
if (ioctl(fd, WDOGIOC_GTICKLER, &tickler) == -1)
tickler = (pid_t) -1;
}
printf("\t%s, %u second period", cp, wm.wm_period);
if (mode != WDOG_MODE_DISARMED) {
switch(mode) {
case WDOG_MODE_KTICKLE:
printf(" [armed, kernel tickle");
break;
case WDOG_MODE_UTICKLE:
printf(" [armed, user tickle");
if (tickler != (pid_t) -1)
printf(", pid %d", tickler);
break;
case WDOG_MODE_ETICKLE:
printf(" [armed, external tickle");
break;
}
printf("]");
}
printf("\n");
}
out:
(void)close(fd);
}
static void
usage(void)
{
fprintf(stderr, "usage: %s\n", getprogname());
fprintf(stderr, " %s -d\n", getprogname());
fprintf(stderr, " %s -e [-A] [-p seconds] timer\n",
getprogname());
fprintf(stderr, " %s -k [-A] [-p seconds] timer\n",
getprogname());
fprintf(stderr, " %s -t\n", getprogname());
fprintf(stderr, " %s -u [-A] [-p seconds] timer\n",
getprogname());
fprintf(stderr, " %s -x [-A] [-p seconds] timer\n",
getprogname());
exit(1);
}