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      1 /*	$NetBSD: shutdown.c,v 1.60 2026/05/11 23:21:07 kre Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1988, 1990, 1993
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. Neither the name of the University nor the names of its contributors
     16  *    may be used to endorse or promote products derived from this software
     17  *    without specific prior written permission.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     29  * SUCH DAMAGE.
     30  */
     31 
     32 #include <sys/cdefs.h>
     33 #ifndef lint
     34 __COPYRIGHT("@(#) Copyright (c) 1988, 1990, 1993\
     35  The Regents of the University of California.  All rights reserved.");
     36 #endif /* not lint */
     37 
     38 #ifndef lint
     39 #if 0
     40 static char sccsid[] = "@(#)shutdown.c	8.4 (Berkeley) 4/28/95";
     41 #else
     42 __RCSID("$NetBSD: shutdown.c,v 1.60 2026/05/11 23:21:07 kre Exp $");
     43 #endif
     44 #endif /* not lint */
     45 
     46 #include <sys/param.h>
     47 #include <sys/time.h>
     48 #include <sys/resource.h>
     49 #include <sys/syslog.h>
     50 
     51 #include <ctype.h>
     52 #include <err.h>
     53 #include <fcntl.h>
     54 #include <pwd.h>
     55 #include <setjmp.h>
     56 #include <signal.h>
     57 #include <stdio.h>
     58 #include <stdlib.h>
     59 #include <string.h>
     60 #include <time.h>
     61 #include <tzfile.h>
     62 #include <unistd.h>
     63 #include <errno.h>
     64 
     65 #include "pathnames.h"
     66 
     67 #ifdef DEBUG
     68 #undef _PATH_NOLOGIN
     69 #define	_PATH_NOLOGIN	"./nologin"
     70 #undef _PATH_FASTBOOT
     71 #define	_PATH_FASTBOOT	"./fastboot"
     72 #endif
     73 
     74 #define	H		*60*60
     75 #define	M		*60
     76 #define	S		*1
     77 #define	NOLOG_TIME	5*60
     78 static const struct interval {
     79 	time_t timeleft, timetowait;
     80 } tlist[] = {
     81 	{ 10 H,  5 H },	{  5 H,  3 H },	{  2 H,  1 H },	{ 1 H, 30 M },
     82 	{ 30 M, 10 M },	{ 20 M, 10 M },	{ 10 M,  5 M },	{ 5 M,  3 M },
     83 	{  2 M,  1 M },	{  1 M, 30 S },	{ 30 S, 30 S },
     84 	{  0, 0 }
     85 };
     86 #undef H
     87 #undef M
     88 #undef S
     89 
     90 static time_t offset, shuttime;
     91 static int dofast, dohalt, doreboot, kidding, nofork, nosync, dodump;
     92 static size_t mbuflen;
     93 static int dopowerdown;
     94 static int dodebug, dosilent, doverbose;
     95 static const char *whom;
     96 static char mbuf[BUFSIZ];
     97 static char *bootstr;
     98 
     99 static void badtime(void) __dead;
    100 static void die_you_gravy_sucking_pig_dog(void) __dead;
    101 static void doitfast(void);
    102 static void dorcshutdown(const char *what);
    103 static void finish(int) __dead;
    104 static void getoffset(char *);
    105 static void loop(void) __dead;
    106 static void nolog(void);
    107 static void timeout(int) __dead;
    108 static void timewarn(time_t);
    109 static void usage(void) __dead;
    110 
    111 int
    112 main(int argc, char *argv[])
    113 {
    114 	char *p, *endp;
    115 	struct passwd *pw;
    116 	size_t arglen, len;
    117 	int ch;
    118 
    119 	(void)setprogname(argv[0]);
    120 #ifndef DEBUG
    121 	if (geteuid())
    122 		errx(1, "%s: Not super-user", strerror(EPERM));
    123 #endif
    124 	while ((ch = getopt(argc, argv, "b:Ddfhknprvxz")) != -1)
    125 		switch (ch) {
    126 		case 'b':
    127 			bootstr = optarg;
    128 			break;
    129 		case 'd':
    130 			dodump = 1;
    131 			break;
    132 		case 'D':
    133 			nofork = 1;
    134 			break;
    135 		case 'f':
    136 			dofast = 1;
    137 			break;
    138 		case 'p':
    139 			dopowerdown = 1;
    140 			/* FALLTHROUGH */
    141 		case 'h':
    142 			dohalt = 1;
    143 			break;
    144 		case 'k':
    145 			kidding = 1;
    146 			break;
    147 		case 'n':
    148 			nosync = 1;
    149 			break;
    150 		case 'r':
    151 			doreboot = 1;
    152 			break;
    153 		case 'v':
    154 			doverbose = 1;
    155 			break;
    156 		case 'x':
    157 			dodebug = 1;
    158 			break;
    159 		case 'z':
    160 			dosilent = 1;
    161 			break;
    162 		case '?':
    163 		default:
    164 			usage();
    165 		}
    166 	argc -= optind;
    167 	argv += optind;
    168 
    169 	if (argc < 1)
    170 		usage();
    171 
    172 	if (dodump && !dohalt && !doreboot)
    173 		doreboot = 1;
    174 
    175 	if (dofast && nosync) {
    176 		warnx("Incompatible options -f and -n");
    177 		usage();
    178 	}
    179 	if (dohalt && doreboot) {
    180 		const char *which_flag = dopowerdown ? "p" : "h";
    181 
    182 		warnx("Incompatible options -%s and -r", which_flag);
    183 		usage();
    184 	}
    185 
    186 	getoffset(*argv++);
    187 
    188 	if (argv[0]) {
    189 		if (strcmp(argv[0], "-") || argv[1]) {
    190 			for (p = mbuf, len = sizeof(mbuf); *argv; ++argv) {
    191 				arglen = strlen(*argv);
    192 				if ((len -= arglen) <= 2)
    193 					break;
    194 				if (p != mbuf)
    195 					*p++ = ' ';
    196 				(void)memmove(p, *argv, arglen);
    197 				p += arglen;
    198 			}
    199 			*p = '\n';
    200 			*++p = '\0';
    201 		} else {
    202 			p = mbuf;
    203 			endp = mbuf + sizeof(mbuf) - 2;
    204 			for (;;) {
    205 				if (!fgets(p, endp - p + 1, stdin))
    206 					break;
    207 				for (; *p &&  p < endp; ++p);
    208 				if (p == endp) {
    209 					*p = '\n';
    210 					*++p = '\0';
    211 					break;
    212 				}
    213 			}
    214 		}
    215 	}
    216 	mbuflen = strlen(mbuf);
    217 
    218 	if (offset)
    219 		(void)printf("Shutdown at %.24s.\n", ctime(&shuttime));
    220 	else
    221 		(void)printf("Shutdown NOW!\n");
    222 
    223 	if (!(whom = getlogin()))
    224 		whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???";
    225 
    226 #ifdef DEBUG
    227 	(void)putc('\n', stdout);
    228 #else
    229 	(void)setpriority(PRIO_PROCESS, 0, PRIO_MIN);
    230 	if (nofork == 0) {
    231 		int forkpid;
    232 
    233 		forkpid = fork();
    234 		if (forkpid == -1) {
    235 			perror("shutdown: fork");
    236 			exit(1);
    237 		}
    238 		if (forkpid) {
    239 			(void)printf("shutdown: [pid %d]\n", forkpid);
    240 			exit(0);
    241 		}
    242 		(void)setsid();
    243 	}
    244 #endif
    245 	openlog("shutdown", LOG_CONS, LOG_AUTH);
    246 	loop();
    247 	/* NOTREACHED */
    248 #ifdef __GNUC__
    249 	return 1;
    250 #endif
    251 }
    252 
    253 static void
    254 loop(void)
    255 {
    256 	const struct interval *tp;
    257 	u_int sltime;
    258 	int logged;
    259 
    260 	if (offset <= NOLOG_TIME) {
    261 		logged = 1;
    262 		nolog();
    263 	}
    264 	else
    265 		logged = 0;
    266 	tp = tlist;
    267 	if (tp->timeleft < offset)
    268 		(void)sleep((u_int)(offset - tp->timeleft));
    269 	else {
    270 		while (offset < tp->timeleft)
    271 			++tp;
    272 		/*
    273 		 * Warn now, if going to sleep more than a fifth of
    274 		 * the next wait time.
    275 		 */
    276 		if ((sltime = offset - tp->timeleft) != 0) {
    277 			if (sltime > tp->timetowait / 5)
    278 				timewarn(offset);
    279 			(void)sleep(sltime);
    280 		}
    281 	}
    282 	for (;; ++tp) {
    283 		timewarn(tp->timeleft);
    284 		if (!logged && tp->timeleft <= NOLOG_TIME) {
    285 			logged = 1;
    286 			nolog();
    287 		}
    288 		(void)sleep((u_int)tp->timetowait);
    289 		if (!tp->timeleft)
    290 			break;
    291 	}
    292 	die_you_gravy_sucking_pig_dog();
    293 }
    294 
    295 static jmp_buf alarmbuf;
    296 
    297 #define	plural(n)	((n) == 1 ? "" : "s")
    298 
    299 static void
    300 timewarn(time_t timeleft)
    301 {
    302 	static int first;
    303 	static char hostname[MAXHOSTNAMELEN + 1];
    304 	FILE *pf;
    305 	char wcmd[MAXPATHLEN + 4];
    306 
    307 	if (!first++) {
    308 		(void)gethostname(hostname, sizeof(hostname));
    309 		hostname[sizeof(hostname) - 1] = '\0';
    310 	}
    311 
    312 	/* undoc -n option to wall suppresses normal wall banner */
    313 	(void)snprintf(wcmd, sizeof wcmd, "%s -n", _PATH_WALL);
    314 	if ((pf = popen(wcmd, "w")) == NULL) {
    315 		syslog(LOG_ERR, "%s: Can't find `%s' (%m)", getprogname(),
    316 		    _PATH_WALL);
    317 		return;
    318 	}
    319 
    320 	(void)fprintf(pf,
    321 	    "\007*** %sSystem shutdown message from %s@%s ***\007\n",
    322 	    timeleft ? "": "FINAL ", whom, hostname);
    323 
    324 	if (timeleft > 10*60)
    325 		(void)fprintf(pf, "System going down at %5.5s\n\n",
    326 		    ctime(&shuttime) + 11);
    327 	else if (timeleft > 59)
    328 		(void)fprintf(pf, "System going down in %ld minute%s\n\n",
    329 		    (long)timeleft / 60, plural((long)timeleft / 60));
    330 	else if (timeleft)
    331 		(void)fprintf(pf, "System going down in ~30 seconds\n\n");
    332 	else
    333 		(void)fprintf(pf, "System going down IMMEDIATELY\n\n");
    334 
    335 	if (mbuflen)
    336 		(void)fwrite(mbuf, 1, mbuflen, pf);
    337 
    338 	/*
    339 	 * play some games, just in case wall doesn't come back
    340 	 * probably unnecessary, given that wall is careful.
    341 	 */
    342 	if (!setjmp(alarmbuf)) {
    343 		(void)signal(SIGALRM, timeout);
    344 		(void)alarm((u_int)30);
    345 		(void)pclose(pf);
    346 		(void)alarm((u_int)0);
    347 		(void)signal(SIGALRM, SIG_DFL);
    348 	}
    349 }
    350 
    351 static void
    352 /*ARGSUSED*/
    353 timeout(int signo)
    354 {
    355 	longjmp(alarmbuf, 1);
    356 }
    357 
    358 static void
    359 die_you_gravy_sucking_pig_dog(void)
    360 {
    361 	const char *what;
    362 
    363 	if (doreboot) {
    364 		what = "reboot";
    365 	} else if (dohalt && dopowerdown) {
    366 		what = "poweroff";
    367 	} else if (dohalt) {
    368 		what = "halt";
    369 	} else {
    370 		what = "shutdown";
    371 	}
    372 
    373 	syslog(LOG_NOTICE, "%s by %s: %s", what, whom, mbuf);
    374 	(void)sleep(2);
    375 
    376 	(void)printf("\r\nSystem shutdown time has arrived\007\007\r\n");
    377 	if (kidding) {
    378 		(void)printf("\rbut you'll have to do it yourself\r\n");
    379 		finish(0);
    380 	}
    381 	if (dofast)
    382 		doitfast();
    383 	dorcshutdown(what);
    384 	if (doreboot || dohalt) {
    385 		const char *args[20];
    386 		const char **arg, *path;
    387 #ifndef DEBUG
    388 		int serrno;
    389 #endif
    390 
    391 		arg = &args[0];
    392 		if (doreboot) {
    393 			path = _PATH_REBOOT;
    394 			*arg++ = "reboot";
    395 		} else {
    396 			path = _PATH_HALT;
    397 			*arg++ = "halt";
    398 		}
    399 		if (doverbose)
    400 			*arg++ = "-v";
    401 		if (dodebug)
    402 			*arg++ = "-x";
    403 		if (dosilent)
    404 			*arg++ = "-z";
    405 		if (dodump)
    406 			*arg++ = "-d";
    407 		if (nosync)
    408 			*arg++ = "-n";
    409 		if (dopowerdown)
    410 			*arg++ = "-p";
    411 		*arg++ = "-l";
    412 		if (bootstr)
    413 			*arg++ = bootstr;
    414 		*arg++ = NULL;
    415 #ifndef DEBUG
    416 		(void)unlink(_PATH_NOLOGIN);
    417 		(void)execve(path, __UNCONST(args), NULL);
    418 		serrno = errno;
    419 		syslog(LOG_ERR, "Can't exec `%s' (%m)", path);
    420 		errno = serrno;
    421 		warn("Can't exec `%s'", path);
    422 #else
    423 		printf("%s", path);
    424 		for (arg = &args[0]; *arg; arg++)
    425 			printf(" %s", *arg);
    426 		printf("\n");
    427 #endif
    428 	} else {
    429 #ifndef DEBUG
    430 		(void)kill(1, SIGTERM);		/* to single user */
    431 #else
    432 		printf("kill 1\n");
    433 #endif
    434 	}
    435 	finish(0);
    436 }
    437 
    438 #define	ATOI2(s)	((s) += 2, ((s)[-2] - '0') * 10 + ((s)[-1] - '0'))
    439 
    440 static void
    441 getoffset(char *timearg)
    442 {
    443 	struct tm *lt;
    444 	char *p;
    445 	time_t now;
    446 	int yearset;
    447 
    448 	(void)time(&now);
    449 	if (!strcasecmp(timearg, "now")) {		/* now */
    450 		offset = 0;
    451 		shuttime = now;
    452 		return;
    453 	}
    454 
    455 	if (*timearg == '+') {				/* +minutes */
    456 		if (!isdigit((unsigned char)*++timearg))
    457 			badtime();
    458 		offset = atoi(timearg) * 60;
    459 		shuttime = now + offset;
    460 		return;
    461 	}
    462 
    463 	/* handle hh:mm by getting rid of the colon */
    464 	for (p = timearg; *p; ++p)
    465 		if (!isascii(*p) || !isdigit((unsigned char)*p)) {
    466 			if (*p == ':' && strlen(p) == 3) {
    467 				p[0] = p[1];
    468 				p[1] = p[2];
    469 				p[2] = '\0';
    470 			}
    471 			else
    472 				badtime();
    473 		}
    474 
    475 	(void)unsetenv("TZ");				/* OUR timezone */
    476 	lt = localtime(&now);				/* current time val */
    477 
    478 	lt->tm_sec = 0;
    479 
    480 	yearset = 0;
    481 	switch (strlen(timearg)) {
    482 	case 12:
    483 		lt->tm_year = ATOI2(timearg) * 100 - TM_YEAR_BASE;
    484 		yearset = 1;
    485 		/* FALLTHROUGH */
    486 	case 10:
    487 		if (yearset) {
    488 			lt->tm_year += ATOI2(timearg);
    489 		} else {
    490 			yearset = ATOI2(timearg);
    491 			if (yearset < 20)
    492 				lt->tm_year = yearset + 2100 - TM_YEAR_BASE;
    493 			else
    494 				lt->tm_year = yearset + 2000 - TM_YEAR_BASE;
    495 		}
    496 		/* FALLTHROUGH */
    497 	case 8:
    498 		lt->tm_mon = ATOI2(timearg);
    499 		if (lt->tm_mon < 1 || lt->tm_mon > 12)
    500 			badtime();
    501 		--lt->tm_mon;
    502 		/* FALLTHROUGH */
    503 	case 6:
    504 		lt->tm_mday = ATOI2(timearg);
    505 		if (lt->tm_mday < 1 || lt->tm_mday > 31)
    506 			badtime();
    507 		/* FALLTHROUGH */
    508 	case 4:
    509 		lt->tm_hour = ATOI2(timearg);
    510 		if (lt->tm_hour < 0 || lt->tm_hour > 23)
    511 			badtime();
    512 		/* FALLTHROUGH */
    513 	case 2:
    514 		lt->tm_min = ATOI2(timearg);
    515 		/* ignore possibility of a leap second */
    516 		if (lt->tm_min < 0 || lt->tm_min > 59)
    517 			badtime();
    518 		break;
    519 	default:
    520 		badtime();
    521 	}
    522 
    523 	if ((shuttime = mktime(lt)) == -1)
    524 		badtime();
    525 	if ((offset = shuttime - now) < 0)
    526 		errx(1, "time is already past");
    527 }
    528 
    529 static void
    530 dorcshutdown(const char *arg)
    531 {
    532 	static char cmd[sizeof(_PATH_RCSHUTDOWN) + 64];
    533 
    534 	if (arg) {
    535 		snprintf(cmd, sizeof(cmd), "set -- %s && . " _PATH_RCSHUTDOWN,
    536 		    arg);
    537 		cmd[sizeof(cmd)-1] = 0;
    538 		arg = cmd;
    539 	} else {
    540 		arg = ". " _PATH_RCSHUTDOWN;
    541 	}
    542 
    543 	(void)printf("\r\nAbout to run shutdown hooks...\r\n");
    544 #ifndef DEBUG
    545 	(void)setuid(0);
    546 	(void)system(arg);
    547 #endif
    548 	(void)sleep(5);		/* Give operator a chance to abort this. */
    549 	(void)printf("\r\nDone running shutdown hooks.\r\n");
    550 }
    551 
    552 #define	FSMSG	"fastboot file for fsck\n"
    553 static void
    554 doitfast(void)
    555 {
    556 	int fastfd;
    557 
    558 	if ((fastfd = open(_PATH_FASTBOOT, O_WRONLY|O_CREAT|O_TRUNC,
    559 	    0664)) >= 0) {
    560 		(void)write(fastfd, FSMSG, sizeof(FSMSG) - 1);
    561 		(void)close(fastfd);
    562 	}
    563 }
    564 
    565 #define	NOMSG	"\n\nNO LOGINS: System going down at "
    566 static void
    567 nolog(void)
    568 {
    569 	int logfd;
    570 	char *ct;
    571 
    572 	if (kidding)
    573 		return;
    574 
    575 	(void)unlink(_PATH_NOLOGIN);	/* in case linked to another file */
    576 	(void)signal(SIGINT, finish);
    577 	(void)signal(SIGHUP, finish);
    578 	(void)signal(SIGQUIT, finish);
    579 	(void)signal(SIGTERM, finish);
    580 	if ((logfd = open(_PATH_NOLOGIN, O_WRONLY|O_CREAT|O_TRUNC,
    581 	    0664)) >= 0) {
    582 		(void)write(logfd, NOMSG, sizeof(NOMSG) - 1);
    583 		ct = ctime(&shuttime);
    584 		(void)write(logfd, ct + 11, 5);
    585 		(void)write(logfd, "\n\n", 2);
    586 		(void)write(logfd, mbuf, strlen(mbuf));
    587 		(void)close(logfd);
    588 	}
    589 }
    590 
    591 static void
    592 /*ARGSUSED*/
    593 finish(int signo)
    594 {
    595 
    596 	if (!kidding)
    597 		(void)unlink(_PATH_NOLOGIN);
    598 	exit(0);
    599 }
    600 
    601 static void
    602 badtime(void)
    603 {
    604 
    605 	warnx("illegal time format");
    606 	usage();
    607 }
    608 
    609 static void
    610 usage(void)
    611 {
    612 
    613 	(void)fprintf(stderr,
    614 	    "Usage: %s [-Ddfhknprvxz] [-b bootstr] time [message ... | -]\n",
    615 	    getprogname());
    616 	exit(1);
    617 }
    618