xref: /dragonfly/sbin/shutdown/shutdown.c (revision 7d3e9a5b)
1 /*
2  * Copyright (c) 1988, 1990, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * @(#) Copyright (c) 1988, 1990, 1993 The Regents of the University of California.  All rights reserved.
30  * @(#)shutdown.c	8.4 (Berkeley) 4/28/95
31  * $FreeBSD: src/sbin/shutdown/shutdown.c,v 1.21.2.1 2001/07/30 10:38:08 dd Exp $
32  */
33 
34 #include <sys/param.h>
35 #include <sys/time.h>
36 #include <sys/resource.h>
37 #include <sys/syslog.h>
38 
39 #include <ctype.h>
40 #include <err.h>
41 #include <errno.h>
42 #include <fcntl.h>
43 #include <pwd.h>
44 #include <setjmp.h>
45 #include <signal.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49 #include <unistd.h>
50 
51 #include "pathnames.h"
52 
53 #ifdef DEBUG
54 #undef _PATH_NOLOGIN
55 #define	_PATH_NOLOGIN	"./nologin"
56 #endif
57 
58 #define	H		*60*60
59 #define	M		*60
60 #define	S		*1
61 #define	NOLOG_TIME	5*60
62 static struct interval {
63 	int timeleft, timetowait;
64 } tlist[] = {
65 	{ 10 H,  5 H },
66 	{  5 H,  3 H },
67 	{  2 H,  1 H },
68 	{  1 H, 30 M },
69 	{ 30 M, 10 M },
70 	{ 20 M, 10 M },
71 	{ 10 M,  5 M },
72 	{  5 M,  3 M },
73 	{  2 M,  1 M },
74 	{  1 M, 30 S },
75 	{ 30 S, 30 S },
76 	{  0  ,  0   }
77 };
78 #undef H
79 #undef M
80 #undef S
81 
82 static time_t offset, shuttime;
83 static int dohalt, dopower, doreboot, killflg, mbuflen, oflag;
84 static char mbuf[BUFSIZ];
85 static const char *nosync, *whom;
86 
87 static void badtime(void);
88 static void die_you_gravy_sucking_pig_dog(void);
89 static void finish(int);
90 static void getoffset(char *);
91 static void loop(void);
92 static void nolog(void);
93 static void timeout(int);
94 static void timewarn(int);
95 static void usage(const char *);
96 
97 extern const char **environ;
98 
99 int
100 main(int argc, char **argv)
101 {
102 	char *p, *endp;
103 	struct passwd *pw;
104 	int arglen, ch, len, readstdin;
105 
106 #ifndef DEBUG
107 	if (geteuid())
108 		errx(1, "NOT super-user");
109 #endif
110 
111 	nosync = NULL;
112 	readstdin = 0;
113 
114 	/*
115 	 * Test for the special case where the utility is called as
116 	 * "poweroff", for which it runs 'shutdown -p now'.
117 	 */
118 	if ((p = strrchr(argv[0], '/')) == NULL)
119 		p = argv[0];
120 	else
121 		++p;
122 	if (strcmp(p, "poweroff") == 0) {
123 		if (getopt(argc, argv, "") != -1)
124 			usage(NULL);
125 		argc -= optind;
126 		argv += optind;
127 		if (argc != 0)
128 			usage(NULL);
129 		dopower = 1;
130 		offset = 0;
131 		(void)time(&shuttime);
132 		goto poweroff;
133 	}
134 
135 	while ((ch = getopt(argc, argv, "-hknopr")) != -1)
136 		switch (ch) {
137 		case '-':
138 			readstdin = 1;
139 			break;
140 		case 'h':
141 			dohalt = 1;
142 			break;
143 		case 'k':
144 			killflg = 1;
145 			break;
146 		case 'n':
147 			nosync = "-n";
148 			break;
149 		case 'o':
150 			oflag = 1;
151 			break;
152 		case 'p':
153 			dopower = 1;
154 			break;
155 		case 'r':
156 			doreboot = 1;
157 			break;
158 		case '?':
159 		default:
160 			usage(NULL);
161 		}
162 	argc -= optind;
163 	argv += optind;
164 
165 #ifdef RESCUE
166 	oflag = 1;
167 #endif
168 
169 	if (argc < 1)
170 		usage(NULL);
171 
172 	if (killflg + doreboot + dohalt + dopower > 1)
173 		usage("incompatible switches -h, -k, -p and -r");
174 
175 	if (oflag && !(dohalt || dopower || doreboot))
176 		usage("-o requires -h, -p or -r");
177 
178 	if (nosync != NULL && !oflag)
179 		usage("-n requires -o");
180 
181 	getoffset(*argv++);
182 
183 poweroff:
184 	if (*argv) {
185 		for (p = mbuf, len = sizeof(mbuf); *argv; ++argv) {
186 			arglen = strlen(*argv);
187 			if ((len -= arglen) <= 2)
188 				break;
189 			if (p != mbuf)
190 				*p++ = ' ';
191 			memmove(p, *argv, arglen);
192 			p += arglen;
193 		}
194 		*p = '\n';
195 		*++p = '\0';
196 	}
197 
198 	if (readstdin) {
199 		p = mbuf;
200 		endp = mbuf + sizeof(mbuf) - 2;
201 		for (;;) {
202 			if (!fgets(p, endp - p + 1, stdin))
203 				break;
204 			for (; *p &&  p < endp; ++p);
205 			if (p == endp) {
206 				*p = '\n';
207 				*++p = '\0';
208 				break;
209 			}
210 		}
211 	}
212 	mbuflen = strlen(mbuf);
213 
214 	if (offset)
215 		printf("Shutdown at %.24s.\n", ctime(&shuttime));
216 	else
217 		printf("Shutdown NOW!\n");
218 
219 	if (!(whom = getlogin()))
220 		whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???";
221 
222 #ifdef DEBUG
223 	putc('\n', stdout);
224 #else
225 	setpriority(PRIO_PROCESS, 0, PRIO_MIN);
226 	{
227 		int forkpid;
228 
229 		forkpid = fork();
230 		if (forkpid == -1)
231 			err(1, "fork");
232 		if (forkpid)
233 			errx(0, "[pid %d]", forkpid);
234 	}
235 	setsid();
236 #endif
237 	openlog("shutdown", LOG_CONS, LOG_AUTH);
238 	loop();
239 	return(0);
240 }
241 
242 static void
243 loop(void)
244 {
245 	struct interval *tp;
246 	u_int sltime;
247 	int logged;
248 
249 	if (offset <= NOLOG_TIME) {
250 		logged = 1;
251 		nolog();
252 	}
253 	else
254 		logged = 0;
255 	tp = tlist;
256 	if (tp->timeleft < offset)
257 		sleep((u_int)(offset - tp->timeleft));
258 	else {
259 		while (tp->timeleft && offset < tp->timeleft)
260 			++tp;
261 		/*
262 		 * Warn now, if going to sleep more than a fifth of
263 		 * the next wait time.
264 		 */
265 		if ((sltime = offset - tp->timeleft)) {
266 			if (sltime > (u_int)(tp->timetowait / 5))
267 				timewarn(offset);
268 			sleep(sltime);
269 		}
270 	}
271 	for (;; ++tp) {
272 		timewarn(tp->timeleft);
273 		if (!logged && tp->timeleft <= NOLOG_TIME) {
274 			logged = 1;
275 			nolog();
276 		}
277 		sleep((u_int)tp->timetowait);
278 		if (!tp->timeleft)
279 			break;
280 	}
281 	die_you_gravy_sucking_pig_dog();
282 }
283 
284 static jmp_buf alarmbuf;
285 
286 static const char *restricted_environ[] = {
287 	"PATH=" _PATH_STDPATH,
288 	NULL
289 };
290 
291 static void
292 timewarn(int timeleft)
293 {
294 	static int first;
295 	static char hostname[MAXHOSTNAMELEN + 1];
296 	FILE *pf;
297 	char wcmd[MAXPATHLEN + 4];
298 
299 	if (!first++)
300 		gethostname(hostname, sizeof(hostname));
301 
302 	/* undoc -n option to wall suppresses normal wall banner */
303 	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 	fprintf(pf,
311 	    "\007*** %sSystem shutdown message from %s@%s ***\007\n",
312 	    timeleft ? "": "FINAL ", whom, hostname);
313 
314 	if (timeleft > 10*60)
315 		fprintf(pf, "System going down at %5.5s\n\n",
316 		    ctime(&shuttime) + 11);
317 	else if (timeleft > 59)
318 		fprintf(pf, "System going down in %d minute%s\n\n",
319 		    timeleft / 60, (timeleft > 60) ? "s" : "");
320 	else if (timeleft)
321 		fprintf(pf, "System going down in %s30 seconds\n\n",
322 		              (offset > 0 && offset < 30 ? "less than " : ""));
323 	else
324 		fprintf(pf, "System going down IMMEDIATELY\n\n");
325 
326 	if (mbuflen)
327 		fwrite(mbuf, sizeof(*mbuf), mbuflen, pf);
328 
329 	/*
330 	 * play some games, just in case wall doesn't come back
331 	 * probably unnecessary, given that wall is careful.
332 	 */
333 	if (!setjmp(alarmbuf)) {
334 		signal(SIGALRM, timeout);
335 		alarm((u_int)30);
336 		pclose(pf);
337 		alarm((u_int)0);
338 		signal(SIGALRM, SIG_DFL);
339 	}
340 }
341 
342 static void
343 timeout(int signo __unused)
344 {
345 	longjmp(alarmbuf, 1);
346 }
347 
348 static void
349 die_you_gravy_sucking_pig_dog(void)
350 {
351 #ifndef DEBUG
352 	char *empty_environ[] = { NULL };
353 #endif
354 
355 	syslog(LOG_NOTICE, "%s by %s: %s",
356 	    doreboot ? "reboot" : dohalt ? "halt" : dopower ? "power-down" :
357 	    "shutdown", whom, mbuf);
358 	sleep(2);
359 
360 	printf("\r\nSystem shutdown time has arrived\007\007\r\n");
361 	if (killflg) {
362 		printf("\rbut you'll have to do it yourself\r\n");
363 		exit(0);
364 	}
365 #ifdef DEBUG
366 	if (doreboot)
367 		printf("reboot");
368 	else if (dohalt)
369 		printf("halt");
370 	else if (dopower)
371 		printf("power-down");
372 	if (nosync != NULL)
373 		printf(" no sync");
374 	printf("\nkill -HUP 1\n");
375 #else
376 	if (!oflag) {
377 		kill(1, doreboot ? SIGINT :	/* reboot */
378 			dohalt ? SIGUSR1 :	/* halt */
379 			dopower ? SIGUSR2 :	/* power-down */
380 			SIGTERM);		/* single-user */
381 	} else {
382 		if (doreboot) {
383 			execle(_PATH_REBOOT, "reboot", "-l", nosync,
384 				NULL, empty_environ);
385 			syslog(LOG_ERR, "shutdown: can't exec %s: %m.",
386 				_PATH_REBOOT);
387 			warn(_PATH_REBOOT);
388 		}
389 		else if (dohalt) {
390 			execle(_PATH_HALT, "halt", "-l", nosync,
391 				NULL, empty_environ);
392 			syslog(LOG_ERR, "shutdown: can't exec %s: %m.",
393 				_PATH_HALT);
394 			warn(_PATH_HALT);
395 		}
396 		else if (dopower) {
397 			execle(_PATH_HALT, "halt", "-l", "-p", nosync,
398 				NULL, empty_environ);
399 			syslog(LOG_ERR, "shutdown: can't exec %s: %m.",
400 				_PATH_HALT);
401 			warn(_PATH_HALT);
402 		}
403 		kill(1, SIGTERM);		/* to single-user */
404 	}
405 #endif
406 	finish(0);
407 }
408 
409 #define	ATOI2(p)	(p[0] - '0') * 10 + (p[1] - '0'); p += 2;
410 
411 static void
412 getoffset(char *timearg)
413 {
414 	struct tm *lt;
415 	char *p;
416 	time_t now;
417 	int maybe_today, this_year;
418 	char *timeunit;
419 
420 	time(&now);
421 
422 	if (!strcasecmp(timearg, "now")) {		/* now */
423 		offset = 0;
424 		shuttime = now;
425 		return;
426 	}
427 
428 	if (*timearg == '+') {				/* +minutes */
429 		if (!isdigit(*++timearg))
430 			badtime();
431 		errno = 0;
432 		offset = strtol(timearg, &timeunit, 10);
433 		if (offset < 0 || offset == LONG_MAX || errno != 0)
434 			badtime();
435 		if (timeunit[0] == '\0' || strcasecmp(timeunit, "m") == 0 ||
436 		    strcasecmp(timeunit, "min") == 0 ||
437 		    strcasecmp(timeunit, "mins") == 0) {
438 			offset *= 60;
439 		} else if (strcasecmp(timeunit, "h") == 0 ||
440 		           strcasecmp(timeunit, "hour") == 0 ||
441 		           strcasecmp(timeunit, "hours") == 0) {
442 			offset *= 60 * 60;
443 		} else if (strcasecmp(timeunit, "s") == 0 ||
444 		           strcasecmp(timeunit, "sec") == 0 ||
445 		           strcasecmp(timeunit, "secs") == 0) {
446 			offset *= 1;
447 		} else {
448 			badtime();
449 		}
450 		/* if ((offset = atoi(timearg) * 60) < 0) */
451 		/* 	badtime(); */
452 		shuttime = now + offset;
453 		return;
454 	}
455 
456 	/* handle hh:mm by getting rid of the colon */
457 	for (p = timearg; *p; ++p)
458 		if (!isascii(*p) || !isdigit(*p)) {
459 			if (*p == ':' && strlen(p) == 3) {
460 				p[0] = p[1];
461 				p[1] = p[2];
462 				p[2] = '\0';
463 			}
464 			else
465 				badtime();
466 		}
467 
468 	unsetenv("TZ");					/* OUR timezone */
469 	lt = localtime(&now);				/* current time val */
470 	maybe_today = 1;
471 
472 	switch(strlen(timearg)) {
473 	case 10:
474 		this_year = lt->tm_year;
475 		lt->tm_year = ATOI2(timearg);
476 		/*
477 		 * check if the specified year is in the next century.
478 		 * allow for one year of user error as many people will
479 		 * enter n - 1 at the start of year n.
480 		 */
481 		if (lt->tm_year < (this_year % 100) - 1)
482 			lt->tm_year += 100;
483 		/* adjust for the year 2000 and beyond */
484 		lt->tm_year += (this_year - (this_year % 100));
485 		/* FALLTHROUGH */
486 	case 8:
487 		lt->tm_mon = ATOI2(timearg);
488 		if (--lt->tm_mon < 0 || lt->tm_mon > 11)
489 			badtime();
490 		/* FALLTHROUGH */
491 	case 6:
492 		maybe_today = 0;
493 		lt->tm_mday = ATOI2(timearg);
494 		if (lt->tm_mday < 1 || lt->tm_mday > 31)
495 			badtime();
496 		/* FALLTHROUGH */
497 	case 4:
498 		lt->tm_hour = ATOI2(timearg);
499 		if (lt->tm_hour < 0 || lt->tm_hour > 23)
500 			badtime();
501 		lt->tm_min = ATOI2(timearg);
502 		if (lt->tm_min < 0 || lt->tm_min > 59)
503 			badtime();
504 		lt->tm_sec = 0;
505 		if ((shuttime = mktime(lt)) == -1)
506 			badtime();
507 
508 		if ((offset = shuttime - now) < 0) {
509 			if (!maybe_today)
510 				errx(1, "that time is already past.");
511 
512 			/*
513 			 * If the user only gave a time, assume that
514 			 * any time earlier than the current time
515 			 * was intended to be that time tomorrow.
516 			 */
517 			lt->tm_mday++;
518 			if ((shuttime = mktime(lt)) == -1)
519 				badtime();
520 			if ((offset = shuttime - now) < 0) {
521 				errx(1, "tomorrow is before today?");
522 			}
523 		}
524 		break;
525 	default:
526 		badtime();
527 	}
528 }
529 
530 #define	NOMSG	"\n\nNO LOGINS: System going down at "
531 static void
532 nolog(void)
533 {
534 	int logfd;
535 	char *ct;
536 
537 	unlink(_PATH_NOLOGIN);	/* in case linked to another file */
538 	signal(SIGINT, finish);
539 	signal(SIGHUP, finish);
540 	signal(SIGQUIT, finish);
541 	signal(SIGTERM, finish);
542 	if ((logfd = open(_PATH_NOLOGIN, O_WRONLY|O_CREAT|O_TRUNC,
543 	    0664)) >= 0) {
544 		write(logfd, NOMSG, sizeof(NOMSG) - 1);
545 		ct = ctime(&shuttime);
546 		write(logfd, ct + 11, 5);
547 		write(logfd, "\n\n", 2);
548 		write(logfd, mbuf, strlen(mbuf));
549 		close(logfd);
550 	}
551 }
552 
553 static void
554 finish(int signo __unused)
555 {
556 	if (!killflg)
557 		unlink(_PATH_NOLOGIN);
558 	exit(0);
559 }
560 
561 static void
562 badtime(void)
563 {
564 	errx(1, "bad time format");
565 }
566 
567 static void
568 usage(const char *cp)
569 {
570 	if (cp != NULL)
571 		warnx("%s", cp);
572 	fprintf(stderr,
573 	    "usage: shutdown [-] [-h | -p | -r | -k] [-o [-n]]"
574 	    " time [warning-message ...]\n"
575 	    "       poweroff\n");
576 	exit(1);
577 }
578