xref: /openbsd-src/sbin/shutdown/shutdown.c (revision db3296cf5c1dd9058ceecc3a29fe4aaa0bd26000)
1 /*	$OpenBSD: shutdown.c,v 1.30 2003/07/30 20:56:19 avsm Exp $	*/
2 /*	$NetBSD: shutdown.c,v 1.9 1995/03/18 15:01:09 cgd Exp $	*/
3 
4 /*
5  * Copyright (c) 1988, 1990, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #ifndef lint
34 static char copyright[] =
35 "@(#) Copyright (c) 1988, 1990, 1993\n\
36 	The Regents of the University of California.  All rights reserved.\n";
37 #endif /* not lint */
38 
39 #ifndef lint
40 #if 0
41 static char sccsid[] = "@(#)shutdown.c	8.2 (Berkeley) 2/16/94";
42 #else
43 static char rcsid[] = "$OpenBSD: shutdown.c,v 1.30 2003/07/30 20:56:19 avsm Exp $";
44 #endif
45 #endif /* not lint */
46 
47 #include <sys/param.h>
48 #include <sys/resource.h>
49 #include <sys/syslog.h>
50 #include <sys/types.h>
51 #include <sys/wait.h>
52 
53 #include <ctype.h>
54 #include <fcntl.h>
55 #include <sys/termios.h>
56 #include <pwd.h>
57 #include <setjmp.h>
58 #include <signal.h>
59 #include <stdio.h>
60 #include <stdlib.h>
61 #include <string.h>
62 #include <time.h>
63 #include <tzfile.h>
64 #include <unistd.h>
65 #include <errno.h>
66 #include <err.h>
67 
68 #include "pathnames.h"
69 
70 #ifdef DEBUG
71 #undef _PATH_NOLOGIN
72 #define	_PATH_NOLOGIN	"./nologin"
73 #undef _PATH_FASTBOOT
74 #define	_PATH_FASTBOOT	"./fastboot"
75 #endif
76 
77 #define	H		*60*60
78 #define	M		*60
79 #define	S		*1
80 #define	NOLOG_TIME	5*60
81 struct interval {
82 	int timeleft, timetowait;
83 } tlist[] = {
84 	{ 10 H,  5 H },
85 	{  5 H,  3 H },
86 	{  2 H,  1 H },
87 	{  1 H, 30 M },
88 	{ 30 M, 10 M },
89 	{ 20 M, 10 M },
90 	{ 10 M,  5 M },
91 	{  5 M,  3 M },
92 	{  2 M,  1 M },
93 	{  1 M, 30 S },
94 	{ 30 S, 30 S },
95 	{    0,    0 }
96 };
97 #undef H
98 #undef M
99 #undef S
100 
101 static time_t offset, shuttime;
102 static int dofast, dohalt, doreboot, dopower, dodump, killflg, mbuflen, nosync;
103 static char *whom, mbuf[BUFSIZ];
104 
105 void badtime(void);
106 void __attribute ((noreturn)) die_you_gravy_sucking_pig_dog(void);
107 void doitfast(void);
108 void __attribute ((noreturn)) finish(int);
109 void getoffset(char *);
110 void __attribute ((noreturn)) loop(void);
111 void nolog(void);
112 void timeout(int);
113 void timewarn(int);
114 void usage(void);
115 
116 int
117 main(int argc, char *argv[])
118 {
119 	char *p, *endp;
120 	struct passwd *pw;
121 	int arglen, ch, len, readstdin;
122 
123 #ifndef DEBUG
124 	if (geteuid())
125 		errx(1, "NOT super-user");
126 #endif
127 	readstdin = 0;
128 	while ((ch = getopt(argc, argv, "dfhknpr-")) != -1)
129 		switch (ch) {
130 		case '-':
131 			readstdin = 1;
132 			break;
133 		case 'd':
134 			dodump = 1;
135 			break;
136 		case 'f':
137 			dofast = 1;
138 			break;
139 		case 'h':
140 			dohalt = 1;
141 			break;
142 		case 'k':
143 			killflg = 1;
144 			break;
145 		case 'n':
146 			nosync = 1;
147 			break;
148 		case 'p':
149 			dopower = 1;
150 			break;
151 		case 'r':
152 			doreboot = 1;
153 			break;
154 		case '?':
155 		default:
156 			usage();
157 		}
158 	argc -= optind;
159 	argv += optind;
160 
161 	if (argc < 1)
162 		usage();
163 
164 	if (dofast && nosync) {
165 		(void)fprintf(stderr,
166 		    "shutdown: incompatible switches -f and -n.\n");
167 		usage();
168 	}
169 	if (doreboot && dohalt) {
170 		(void)fprintf(stderr,
171 		    "shutdown: incompatible switches -h and -r.\n");
172 		usage();
173 	}
174 	if (dopower && !dohalt) {
175 		(void)fprintf(stderr,
176 		    "shutdown: switch -p must be used with -h.\n");
177 		usage();
178 	}
179 	getoffset(*argv++);
180 
181 	if (*argv) {
182 		for (p = mbuf, len = sizeof(mbuf); *argv; ++argv) {
183 			arglen = strlen(*argv);
184 			if ((len -= arglen) <= 2)
185 				break;
186 			if (p != mbuf)
187 				*p++ = ' ';
188 			memcpy(p, *argv, arglen);
189 			p += arglen;
190 		}
191 		*p = '\n';
192 		*++p = '\0';
193 	}
194 
195 	if (readstdin) {
196 		p = mbuf;
197 		endp = mbuf + sizeof(mbuf) - 2;
198 		for (;;) {
199 			if (!fgets(p, endp - p + 1, stdin))
200 				break;
201 			for (; *p &&  p < endp; ++p);
202 			if (p == endp) {
203 				*p = '\n';
204 				*++p = '\0';
205 				break;
206 			}
207 		}
208 	}
209 	mbuflen = strlen(mbuf);
210 
211 	if (offset)
212 		(void)printf("Shutdown at %.24s.\n", ctime(&shuttime));
213 	else
214 		(void)printf("Shutdown NOW!\n");
215 
216 	if (!(whom = getlogin()))
217 		whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???";
218 
219 #ifdef DEBUG
220 	(void)putc('\n', stdout);
221 #else
222 	(void)setpriority(PRIO_PROCESS, 0, PRIO_MIN);
223 	{
224 		pid_t forkpid;
225 
226 		forkpid = fork();
227 		if (forkpid == -1)
228 			err(1, "fork");
229 		if (forkpid) {
230 			(void)printf("shutdown: [pid %ld]\n", (long)forkpid);
231 			exit(0);
232 		}
233 	}
234 	setsid();
235 #endif
236 	openlog("shutdown", LOG_CONS, LOG_AUTH);
237 	loop();
238 	/* NOTREACHED */
239 }
240 
241 void
242 loop(void)
243 {
244 	struct interval *tp;
245 	u_int sltime;
246 	int logged;
247 
248 	if (offset <= NOLOG_TIME) {
249 		logged = 1;
250 		nolog();
251 	}
252 	else
253 		logged = 0;
254 	tp = tlist;
255 	if (tp->timeleft < offset)
256 		(void)sleep((u_int)(offset - tp->timeleft));
257 	else {
258 		while (offset < tp->timeleft)
259 			++tp;
260 		/*
261 		 * Warn now, if going to sleep more than a fifth of
262 		 * the next wait time.
263 		 */
264 		if ((sltime = offset - tp->timeleft)) {
265 			if (sltime > tp->timetowait / 5)
266 				timewarn(offset);
267 			(void)sleep(sltime);
268 		}
269 	}
270 	for (;; ++tp) {
271 		timewarn(tp->timeleft);
272 		if (!logged && tp->timeleft <= NOLOG_TIME) {
273 			logged = 1;
274 			nolog();
275 		}
276 		(void)sleep((u_int)tp->timetowait);
277 		if (!tp->timeleft)
278 			break;
279 	}
280 	die_you_gravy_sucking_pig_dog();
281 }
282 
283 static jmp_buf alarmbuf;
284 
285 static char *restricted_environ[] = {
286 	"PATH=" _PATH_STDPATH,
287 	NULL
288 };
289 
290 void
291 timewarn(int timeleft)
292 {
293 	static int first;
294 	static char hostname[MAXHOSTNAMELEN];
295 	FILE *pf;
296 	char wcmd[MAXPATHLEN + 4];
297 	extern char **environ;
298 
299 	if (!first++)
300 		(void)gethostname(hostname, sizeof(hostname));
301 
302 	/* undoc -n option to wall suppresses normal wall banner */
303 	(void)snprintf(wcmd, sizeof(wcmd), "%s -n", _PATH_WALL);
304 	environ = restricted_environ;
305 	if (!(pf = popen(wcmd, "w"))) {
306 		syslog(LOG_ERR, "shutdown: can't find %s: %m", _PATH_WALL);
307 		return;
308 	}
309 
310 	(void)fprintf(pf,
311 	    "\007*** %sSystem shutdown message from %s@%s ***\007\n",
312 	    timeleft ? "": "FINAL ", whom, hostname);
313 
314 	if (timeleft > 10*60)
315 		(void)fprintf(pf, "System going down at %5.5s\n\n",
316 		    ctime(&shuttime) + 11);
317 	else if (timeleft > 59)
318 		(void)fprintf(pf, "System going down in %d minute%s\n\n",
319 		    timeleft / 60, (timeleft > 60) ? "s" : "");
320 	else if (timeleft)
321 		(void)fprintf(pf, "System going down in 30 seconds\n\n");
322 	else
323 		(void)fprintf(pf, "System going down IMMEDIATELY\n\n");
324 
325 	if (mbuflen)
326 		(void)fwrite(mbuf, sizeof(*mbuf), mbuflen, pf);
327 
328 	/*
329 	 * play some games, just in case wall doesn't come back
330 	 * probably unecessary, given that wall is careful.
331 	 */
332 	if (!setjmp(alarmbuf)) {
333 		(void)signal(SIGALRM, timeout);
334 		(void)alarm((u_int)30);
335 		(void)pclose(pf);
336 		(void)alarm((u_int)0);
337 		(void)signal(SIGALRM, SIG_DFL);
338 	}
339 }
340 
341 void
342 timeout(int signo)
343 {
344 	longjmp(alarmbuf, 1);		/* XXX signal/longjmp resource leaks */
345 }
346 
347 void
348 die_you_gravy_sucking_pig_dog(void)
349 {
350 
351 	syslog(LOG_NOTICE, "%s by %s: %s",
352 	    doreboot ? "reboot" : dohalt ? "halt" : "shutdown", whom, mbuf);
353 	(void)sleep(2);
354 
355 	(void)printf("\r\nSystem shutdown time has arrived\007\007\r\n");
356 	if (killflg) {
357 		(void)printf("\rbut you'll have to do it yourself\r\n");
358 		finish(0);
359 	}
360 	if (dofast)
361 		doitfast();
362 #ifdef DEBUG
363 	if (doreboot)
364 		(void)printf("reboot");
365 	else if (dohalt)
366 		(void)printf("halt");
367 	if (nosync)
368 		(void)printf(" no sync");
369 	if (dofast)
370 		(void)printf(" no fsck");
371 	if (dodump)
372 		(void)printf(" with dump");
373 	(void)printf("\nkill -HUP 1\n");
374 #else
375 	if (doreboot) {
376 		execle(_PATH_REBOOT, "reboot", "-l",
377 		    (nosync ? "-n" : (dodump ? "-d" : NULL)),
378 		    (dodump ? "-d" : NULL), (char *)NULL, (char *)NULL);
379 		syslog(LOG_ERR, "shutdown: can't exec %s: %m.", _PATH_REBOOT);
380 		warn(_PATH_REBOOT);
381 	}
382 	else if (dohalt) {
383 		execle(_PATH_HALT, "halt", "-l",
384 		    (dopower ? "-p" : (nosync ? "-n" : (dodump ? "-d" : NULL))),
385 		    (nosync ? "-n" : (dodump ? "-d" : NULL)),
386 		    (dodump ? "-d" : NULL), (char *)NULL, (char *)NULL);
387 		syslog(LOG_ERR, "shutdown: can't exec %s: %m.", _PATH_HALT);
388 		warn(_PATH_HALT);
389 	}
390 	if (access(_PATH_RC, R_OK) != -1) {
391 		pid_t pid;
392 		struct termios t;
393 		int fd;
394 
395 		switch ((pid = fork())) {
396 		case -1:
397 			break;
398 		case 0:
399 			if (revoke(_PATH_CONSOLE) == -1)
400 				perror("revoke");
401 			if (setsid() == -1)
402 				perror("setsid");
403 			fd = open(_PATH_CONSOLE, O_RDWR);
404 			if (fd == -1)
405 				perror("open");
406 			dup2(fd, 0);
407 			dup2(fd, 1);
408 			dup2(fd, 2);
409 			if (fd > 2)
410 				close(fd);
411 
412 			/* At a minimum... */
413 			tcgetattr(0, &t);
414 			t.c_oflag |= (ONLCR | OPOST);
415 			tcsetattr(0, TCSANOW, &t);
416 
417 			execl(_PATH_BSHELL, "sh", _PATH_RC, "shutdown", (char *)NULL);
418 			_exit(1);
419 		default:
420 			waitpid(pid, NULL, 0);
421 		}
422 	}
423 	(void)kill(1, SIGTERM);		/* to single user */
424 #endif
425 	finish(0);
426 }
427 
428 #define	ATOI2(p)	(p[0] - '0') * 10 + (p[1] - '0'); p += 2;
429 
430 void
431 getoffset(char *timearg)
432 {
433 	struct tm *lt;
434 	char *p;
435 	time_t now;
436 	int this_year;
437 
438 	if (!strcasecmp(timearg, "now")) {		/* now */
439 		offset = 0;
440 		return;
441 	}
442 
443 	(void)time(&now);
444 	if (*timearg == '+') {				/* +minutes */
445 		if (!isdigit(*++timearg))
446 			badtime();
447 		offset = atoi(timearg) * 60;
448 		shuttime = now + offset;
449 		return;
450 	}
451 
452 	/* handle hh:mm by getting rid of the colon */
453 	for (p = timearg; *p; ++p) {
454 		if (!isascii(*p) || !isdigit(*p)) {
455 			if (*p == ':' && strlen(p) == 3) {
456 				p[0] = p[1];
457 				p[1] = p[2];
458 				p[2] = '\0';
459 			} else
460 				badtime();
461 		}
462 	}
463 
464 	unsetenv("TZ");					/* OUR timezone */
465 	lt = localtime(&now);				/* current time val */
466 
467 	switch(strlen(timearg)) {
468 	case 10:
469 		this_year = lt->tm_year;
470 		lt->tm_year = ATOI2(timearg);
471 		/*
472 		 * check if the specified year is in the next century.
473 		 * allow for one year of user error as many people will
474 		 * enter n - 1 at the start of year n.
475 		 */
476 		if (lt->tm_year < (this_year % 100) - 1)
477 			lt->tm_year += 100;
478 		/* adjust for the year 2000 and beyond */
479 		lt->tm_year += (this_year - (this_year % 100));
480 		/* FALLTHROUGH */
481 	case 8:
482 		lt->tm_mon = ATOI2(timearg);
483 		if (--lt->tm_mon < 0 || lt->tm_mon > 11)
484 			badtime();
485 		/* FALLTHROUGH */
486 	case 6:
487 		lt->tm_mday = ATOI2(timearg);
488 		if (lt->tm_mday < 1 || lt->tm_mday > 31)
489 			badtime();
490 		/* FALLTHROUGH */
491 	case 4:
492 		lt->tm_hour = ATOI2(timearg);
493 		if (lt->tm_hour < 0 || lt->tm_hour > 23)
494 			badtime();
495 		lt->tm_min = ATOI2(timearg);
496 		if (lt->tm_min < 0 || lt->tm_min > 59)
497 			badtime();
498 		lt->tm_sec = 0;
499 		if ((shuttime = mktime(lt)) == -1)
500 			badtime();
501 		if ((offset = shuttime - now) < 0)
502 			errx(1, "that time is already past.");
503 		break;
504 	default:
505 		badtime();
506 	}
507 }
508 
509 #define	FSMSG	"fastboot file for fsck\n"
510 void
511 doitfast(void)
512 {
513 	int fastfd;
514 
515 	if ((fastfd = open(_PATH_FASTBOOT, O_WRONLY|O_CREAT|O_TRUNC,
516 	    0664)) >= 0) {
517 		(void)write(fastfd, FSMSG, sizeof(FSMSG) - 1);
518 		(void)close(fastfd);
519 	}
520 }
521 
522 #define	NOMSG	"\n\nNO LOGINS: System going down at "
523 void
524 nolog(void)
525 {
526 	int logfd;
527 	char *ct;
528 
529 	(void)unlink(_PATH_NOLOGIN);	/* in case linked to another file */
530 	(void)signal(SIGINT, finish);
531 	(void)signal(SIGHUP, finish);
532 	(void)signal(SIGQUIT, finish);
533 	(void)signal(SIGTERM, finish);
534 	if ((logfd = open(_PATH_NOLOGIN, O_WRONLY|O_CREAT|O_TRUNC,
535 	    0664)) >= 0) {
536 		(void)write(logfd, NOMSG, sizeof(NOMSG) - 1);
537 		ct = ctime(&shuttime);
538 		(void)write(logfd, ct + 11, 5);
539 		(void)write(logfd, "\n\n", 2);
540 		(void)write(logfd, mbuf, strlen(mbuf));
541 		(void)close(logfd);
542 	}
543 }
544 
545 void
546 finish(int signo)
547 {
548 	if (!killflg)
549 		(void)unlink(_PATH_NOLOGIN);
550 	if (signo == 0)
551 		exit(0);
552 	else
553 		_exit(0);
554 }
555 
556 void
557 badtime(void)
558 {
559 	errx(1, "bad time format.");
560 }
561 
562 void
563 usage(void)
564 {
565 	fprintf(stderr, "usage: shutdown [-dfhknpr] shutdowntime [ message ]\n");
566 	exit(1);
567 }
568