xref: /freebsd/sbin/shutdown/shutdown.c (revision 1b6c76a2fe091c74f08427e6c870851025a9cf67)
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. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University 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 REGENTS 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 REGENTS 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 #ifndef lint
35 static const char copyright[] =
36 "@(#) Copyright (c) 1988, 1990, 1993\n\
37 	The Regents of the University of California.  All rights reserved.\n";
38 #endif /* not lint */
39 
40 #ifndef lint
41 #if 0
42 static char sccsid[] = "@(#)shutdown.c	8.4 (Berkeley) 4/28/95";
43 #endif
44 static const char rcsid[] =
45   "$FreeBSD$";
46 #endif /* not lint */
47 
48 #include <sys/param.h>
49 #include <sys/time.h>
50 #include <sys/resource.h>
51 #include <sys/syslog.h>
52 
53 #include <ctype.h>
54 #include <err.h>
55 #include <fcntl.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 <unistd.h>
63 
64 #include "pathnames.h"
65 
66 #ifdef DEBUG
67 #undef _PATH_NOLOGIN
68 #define	_PATH_NOLOGIN	"./nologin"
69 #endif
70 
71 #define	H		*60*60
72 #define	M		*60
73 #define	S		*1
74 #define	NOLOG_TIME	5*60
75 struct interval {
76 	int timeleft, timetowait;
77 } tlist[] = {
78 	{ 10 H,  5 H },
79 	{  5 H,  3 H },
80 	{  2 H,  1 H },
81 	{  1 H, 30 M },
82 	{ 30 M, 10 M },
83 	{ 20 M, 10 M },
84 	{ 10 M,  5 M },
85 	{  5 M,  3 M },
86 	{  2 M,  1 M },
87 	{  1 M, 30 S },
88 	{ 30 S, 30 S },
89 	{  0  ,  0   }
90 };
91 #undef H
92 #undef M
93 #undef S
94 
95 static time_t offset, shuttime;
96 static int dohalt, dopower, doreboot, killflg, mbuflen, oflag;
97 static char *nosync, *whom, mbuf[BUFSIZ];
98 
99 void badtime __P((void));
100 void die_you_gravy_sucking_pig_dog __P((void));
101 void finish __P((int));
102 void getoffset __P((char *));
103 void loop __P((void));
104 void nolog __P((void));
105 void timeout __P((int));
106 void timewarn __P((int));
107 void usage __P((const char *));
108 
109 int
110 main(argc, argv)
111 	int argc;
112 	char *argv[];
113 {
114 	register char *p, *endp;
115 	struct passwd *pw;
116 	int arglen, ch, len, readstdin;
117 
118 #ifndef DEBUG
119 	if (geteuid())
120 		errx(1, "NOT super-user");
121 #endif
122 	nosync = NULL;
123 	readstdin = 0;
124 	while ((ch = getopt(argc, argv, "-hknopr")) != -1)
125 		switch (ch) {
126 		case '-':
127 			readstdin = 1;
128 			break;
129 		case 'h':
130 			dohalt = 1;
131 			break;
132 		case 'k':
133 			killflg = 1;
134 			break;
135 		case 'n':
136 			nosync = "-n";
137 			break;
138 		case 'o':
139 			oflag = 1;
140 			break;
141 		case 'p':
142 			dopower = 1;
143 			break;
144 		case 'r':
145 			doreboot = 1;
146 			break;
147 		case '?':
148 		default:
149 			usage((char *)NULL);
150 		}
151 	argc -= optind;
152 	argv += optind;
153 
154 	if (argc < 1)
155 		usage((char *)NULL);
156 
157 	if (killflg + doreboot + dohalt + dopower > 1)
158 		usage("incompatible switches -h, -k, -p and -r");
159 
160 	if (oflag && !(dohalt || dopower || doreboot))
161 		usage("-o requires -h, -p or -r");
162 
163 	if (nosync != NULL && !oflag)
164 		usage("-n requires -o");
165 
166 	getoffset(*argv++);
167 
168 	if (*argv) {
169 		for (p = mbuf, len = sizeof(mbuf); *argv; ++argv) {
170 			arglen = strlen(*argv);
171 			if ((len -= arglen) <= 2)
172 				break;
173 			if (p != mbuf)
174 				*p++ = ' ';
175 			memmove(p, *argv, arglen);
176 			p += arglen;
177 		}
178 		*p = '\n';
179 		*++p = '\0';
180 	}
181 
182 	if (readstdin) {
183 		p = mbuf;
184 		endp = mbuf + sizeof(mbuf) - 2;
185 		for (;;) {
186 			if (!fgets(p, endp - p + 1, stdin))
187 				break;
188 			for (; *p &&  p < endp; ++p);
189 			if (p == endp) {
190 				*p = '\n';
191 				*++p = '\0';
192 				break;
193 			}
194 		}
195 	}
196 	mbuflen = strlen(mbuf);
197 
198 	if (offset)
199 		(void)printf("Shutdown at %.24s.\n", ctime(&shuttime));
200 	else
201 		(void)printf("Shutdown NOW!\n");
202 
203 	if (!(whom = getlogin()))
204 		whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???";
205 
206 #ifdef DEBUG
207 	(void)putc('\n', stdout);
208 #else
209 	(void)setpriority(PRIO_PROCESS, 0, PRIO_MIN);
210 	{
211 		int forkpid;
212 
213 		forkpid = fork();
214 		if (forkpid == -1)
215 			err(1, "fork");
216 		if (forkpid)
217 			errx(0, "[pid %d]", forkpid);
218 	}
219 	setsid();
220 #endif
221 	openlog("shutdown", LOG_CONS, LOG_AUTH);
222 	loop();
223 	return(0);
224 }
225 
226 void
227 loop()
228 {
229 	struct interval *tp;
230 	u_int sltime;
231 	int logged;
232 
233 	if (offset <= NOLOG_TIME) {
234 		logged = 1;
235 		nolog();
236 	}
237 	else
238 		logged = 0;
239 	tp = tlist;
240 	if (tp->timeleft < offset)
241 		(void)sleep((u_int)(offset - tp->timeleft));
242 	else {
243 		while (tp->timeleft && offset < tp->timeleft)
244 			++tp;
245 		/*
246 		 * Warn now, if going to sleep more than a fifth of
247 		 * the next wait time.
248 		 */
249 		if ((sltime = offset - tp->timeleft)) {
250 			if (sltime > tp->timetowait / 5)
251 				timewarn(offset);
252 			(void)sleep(sltime);
253 		}
254 	}
255 	for (;; ++tp) {
256 		timewarn(tp->timeleft);
257 		if (!logged && tp->timeleft <= NOLOG_TIME) {
258 			logged = 1;
259 			nolog();
260 		}
261 		(void)sleep((u_int)tp->timetowait);
262 		if (!tp->timeleft)
263 			break;
264 	}
265 	die_you_gravy_sucking_pig_dog();
266 }
267 
268 static jmp_buf alarmbuf;
269 
270 static char *restricted_environ[] = {
271 	"PATH=" _PATH_STDPATH,
272 	NULL
273 };
274 
275 void
276 timewarn(timeleft)
277 	int timeleft;
278 {
279 	static int first;
280 	static char hostname[MAXHOSTNAMELEN + 1];
281 	FILE *pf;
282 	char wcmd[MAXPATHLEN + 4];
283 	extern char **environ;
284 
285 	if (!first++)
286 		(void)gethostname(hostname, sizeof(hostname));
287 
288 	/* undoc -n option to wall suppresses normal wall banner */
289 	(void)snprintf(wcmd, sizeof(wcmd), "%s -n", _PATH_WALL);
290 	environ = restricted_environ;
291 	if (!(pf = popen(wcmd, "w"))) {
292 		syslog(LOG_ERR, "shutdown: can't find %s: %m", _PATH_WALL);
293 		return;
294 	}
295 
296 	(void)fprintf(pf,
297 	    "\007*** %sSystem shutdown message from %s@%s ***\007\n",
298 	    timeleft ? "": "FINAL ", whom, hostname);
299 
300 	if (timeleft > 10*60)
301 		(void)fprintf(pf, "System going down at %5.5s\n\n",
302 		    ctime(&shuttime) + 11);
303 	else if (timeleft > 59)
304 		(void)fprintf(pf, "System going down in %d minute%s\n\n",
305 		    timeleft / 60, (timeleft > 60) ? "s" : "");
306 	else if (timeleft)
307 		(void)fprintf(pf, "System going down in 30 seconds\n\n");
308 	else
309 		(void)fprintf(pf, "System going down IMMEDIATELY\n\n");
310 
311 	if (mbuflen)
312 		(void)fwrite(mbuf, sizeof(*mbuf), mbuflen, pf);
313 
314 	/*
315 	 * play some games, just in case wall doesn't come back
316 	 * probably unnecessary, given that wall is careful.
317 	 */
318 	if (!setjmp(alarmbuf)) {
319 		(void)signal(SIGALRM, timeout);
320 		(void)alarm((u_int)30);
321 		(void)pclose(pf);
322 		(void)alarm((u_int)0);
323 		(void)signal(SIGALRM, SIG_DFL);
324 	}
325 }
326 
327 void
328 timeout(signo)
329 	int signo;
330 {
331 	longjmp(alarmbuf, 1);
332 }
333 
334 void
335 die_you_gravy_sucking_pig_dog()
336 {
337 	char *empty_environ[] = { NULL };
338 
339 	syslog(LOG_NOTICE, "%s by %s: %s",
340 	    doreboot ? "reboot" : dohalt ? "halt" : dopower ? "power-down" :
341 	    "shutdown", whom, mbuf);
342 	(void)sleep(2);
343 
344 	(void)printf("\r\nSystem shutdown time has arrived\007\007\r\n");
345 	if (killflg) {
346 		(void)printf("\rbut you'll have to do it yourself\r\n");
347 		exit(0);
348 	}
349 #ifdef DEBUG
350 	if (doreboot)
351 		(void)printf("reboot");
352 	else if (dohalt)
353 		(void)printf("halt");
354 	else if (dopower)
355 		(void)printf("power-down");
356 	if (nosync != NULL)
357 		(void)printf(" no sync");
358 	(void)printf("\nkill -HUP 1\n");
359 #else
360 	if (!oflag) {
361 		(void)kill(1, doreboot ? SIGINT :	/* reboot */
362 			      dohalt ? SIGUSR1 :	/* halt */
363 			      dopower ? SIGUSR2 :	/* power-down */
364 			      SIGTERM);			/* single-user */
365 	} else {
366 		if (doreboot) {
367 			execle(_PATH_REBOOT, "reboot", "-l", nosync,
368 				(char *)NULL, empty_environ);
369 			syslog(LOG_ERR, "shutdown: can't exec %s: %m.",
370 				_PATH_REBOOT);
371 			warn(_PATH_REBOOT);
372 		}
373 		else if (dohalt) {
374 			execle(_PATH_HALT, "halt", "-l", nosync,
375 				(char *)NULL, empty_environ);
376 			syslog(LOG_ERR, "shutdown: can't exec %s: %m.",
377 				_PATH_HALT);
378 			warn(_PATH_HALT);
379 		}
380 		else if (dopower) {
381 			execle(_PATH_HALT, "halt", "-l", "-p", nosync,
382 				(char *)NULL, empty_environ);
383 			syslog(LOG_ERR, "shutdown: can't exec %s: %m.",
384 				_PATH_HALT);
385 			warn(_PATH_HALT);
386 		}
387 		(void)kill(1, SIGTERM);		/* to single-user */
388 	}
389 #endif
390 	finish(0);
391 }
392 
393 #define	ATOI2(p)	(p[0] - '0') * 10 + (p[1] - '0'); p += 2;
394 
395 void
396 getoffset(timearg)
397 	register char *timearg;
398 {
399 	register struct tm *lt;
400 	register char *p;
401 	time_t now;
402 	int this_year;
403 
404 	(void)time(&now);
405 
406 	if (!strcasecmp(timearg, "now")) {		/* now */
407 		offset = 0;
408 		shuttime = now;
409 		return;
410 	}
411 
412 	if (*timearg == '+') {				/* +minutes */
413 		if (!isdigit(*++timearg))
414 			badtime();
415 		if ((offset = atoi(timearg) * 60) < 0)
416 			badtime();
417 		shuttime = now + offset;
418 		return;
419 	}
420 
421 	/* handle hh:mm by getting rid of the colon */
422 	for (p = timearg; *p; ++p)
423 		if (!isascii(*p) || !isdigit(*p)) {
424 			if (*p == ':' && strlen(p) == 3) {
425 				p[0] = p[1];
426 				p[1] = p[2];
427 				p[2] = '\0';
428 			}
429 			else
430 				badtime();
431 		}
432 
433 	unsetenv("TZ");					/* OUR timezone */
434 	lt = localtime(&now);				/* current time val */
435 
436 	switch(strlen(timearg)) {
437 	case 10:
438 		this_year = lt->tm_year;
439 		lt->tm_year = ATOI2(timearg);
440 		/*
441 		 * check if the specified year is in the next century.
442 		 * allow for one year of user error as many people will
443 		 * enter n - 1 at the start of year n.
444 		 */
445 		if (lt->tm_year < (this_year % 100) - 1)
446 			lt->tm_year += 100;
447 		/* adjust for the year 2000 and beyond */
448 		lt->tm_year += (this_year - (this_year % 100));
449 		/* FALLTHROUGH */
450 	case 8:
451 		lt->tm_mon = ATOI2(timearg);
452 		if (--lt->tm_mon < 0 || lt->tm_mon > 11)
453 			badtime();
454 		/* FALLTHROUGH */
455 	case 6:
456 		lt->tm_mday = ATOI2(timearg);
457 		if (lt->tm_mday < 1 || lt->tm_mday > 31)
458 			badtime();
459 		/* FALLTHROUGH */
460 	case 4:
461 		lt->tm_hour = ATOI2(timearg);
462 		if (lt->tm_hour < 0 || lt->tm_hour > 23)
463 			badtime();
464 		lt->tm_min = ATOI2(timearg);
465 		if (lt->tm_min < 0 || lt->tm_min > 59)
466 			badtime();
467 		lt->tm_sec = 0;
468 		if ((shuttime = mktime(lt)) == -1)
469 			badtime();
470 		if ((offset = shuttime - now) < 0)
471 			errx(1, "that time is already past.");
472 		break;
473 	default:
474 		badtime();
475 	}
476 }
477 
478 #define	NOMSG	"\n\nNO LOGINS: System going down at "
479 void
480 nolog()
481 {
482 	int logfd;
483 	char *ct;
484 
485 	(void)unlink(_PATH_NOLOGIN);	/* in case linked to another file */
486 	(void)signal(SIGINT, finish);
487 	(void)signal(SIGHUP, finish);
488 	(void)signal(SIGQUIT, finish);
489 	(void)signal(SIGTERM, finish);
490 	if ((logfd = open(_PATH_NOLOGIN, O_WRONLY|O_CREAT|O_TRUNC,
491 	    0664)) >= 0) {
492 		(void)write(logfd, NOMSG, sizeof(NOMSG) - 1);
493 		ct = ctime(&shuttime);
494 		(void)write(logfd, ct + 11, 5);
495 		(void)write(logfd, "\n\n", 2);
496 		(void)write(logfd, mbuf, strlen(mbuf));
497 		(void)close(logfd);
498 	}
499 }
500 
501 void
502 finish(signo)
503 	int signo;
504 {
505 	if (!killflg)
506 		(void)unlink(_PATH_NOLOGIN);
507 	exit(0);
508 }
509 
510 void
511 badtime()
512 {
513 	errx(1, "bad time format");
514 }
515 
516 void
517 usage(cp)
518 	const char *cp;
519 {
520 	if (cp != NULL)
521 		warnx("%s", cp);
522 	(void)fprintf(stderr,
523 	    "usage: shutdown [-] [-h | -p | -r | -k] [-o [-n]]"
524 	    " time [warning-message ...]\n");
525 	exit(1);
526 }
527