xref: /freebsd/sbin/shutdown/shutdown.c (revision 1e413cf93298b5b97441a21d9a50fdcd0ee9945e)
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  * 4. 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 
30 #if 0
31 #ifndef lint
32 static const char copyright[] =
33 "@(#) Copyright (c) 1988, 1990, 1993\n\
34 	The Regents of the University of California.  All rights reserved.\n";
35 #endif /* not lint */
36 
37 #ifndef lint
38 static char sccsid[] = "@(#)shutdown.c	8.4 (Berkeley) 4/28/95";
39 #endif /* not lint */
40 #endif
41 #include <sys/cdefs.h>
42 __FBSDID("$FreeBSD$");
43 
44 #include <sys/param.h>
45 #include <sys/time.h>
46 #include <sys/resource.h>
47 #include <sys/syslog.h>
48 
49 #include <ctype.h>
50 #include <err.h>
51 #include <fcntl.h>
52 #include <paths.h>
53 #include <pwd.h>
54 #include <setjmp.h>
55 #include <signal.h>
56 #include <stdio.h>
57 #include <stdlib.h>
58 #include <string.h>
59 #include <unistd.h>
60 
61 #ifdef DEBUG
62 #undef _PATH_NOLOGIN
63 #define	_PATH_NOLOGIN	"./nologin"
64 #endif
65 
66 #define	H		*60*60
67 #define	M		*60
68 #define	S		*1
69 #define	NOLOG_TIME	5*60
70 struct interval {
71 	int timeleft, timetowait;
72 } tlist[] = {
73 	{ 10 H,  5 H },
74 	{  5 H,  3 H },
75 	{  2 H,  1 H },
76 	{  1 H, 30 M },
77 	{ 30 M, 10 M },
78 	{ 20 M, 10 M },
79 	{ 10 M,  5 M },
80 	{  5 M,  3 M },
81 	{  2 M,  1 M },
82 	{  1 M, 30 S },
83 	{ 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 dohalt, dopower, doreboot, killflg, mbuflen, oflag;
92 static char mbuf[BUFSIZ];
93 static const char *nosync, *whom;
94 
95 void badtime(void);
96 void die_you_gravy_sucking_pig_dog(void);
97 void finish(int);
98 void getoffset(char *);
99 void loop(void);
100 void nolog(void);
101 void timeout(int);
102 void timewarn(int);
103 void usage(const char *);
104 
105 extern const char **environ;
106 
107 int
108 main(int argc, char **argv)
109 {
110 	char *p, *endp;
111 	struct passwd *pw;
112 	int arglen, ch, len, readstdin;
113 
114 #ifndef DEBUG
115 	if (geteuid())
116 		errx(1, "NOT super-user");
117 #endif
118 	nosync = NULL;
119 	readstdin = 0;
120 	while ((ch = getopt(argc, argv, "-hknopr")) != -1)
121 		switch (ch) {
122 		case '-':
123 			readstdin = 1;
124 			break;
125 		case 'h':
126 			dohalt = 1;
127 			break;
128 		case 'k':
129 			killflg = 1;
130 			break;
131 		case 'n':
132 			nosync = "-n";
133 			break;
134 		case 'o':
135 			oflag = 1;
136 			break;
137 		case 'p':
138 			dopower = 1;
139 			break;
140 		case 'r':
141 			doreboot = 1;
142 			break;
143 		case '?':
144 		default:
145 			usage((char *)NULL);
146 		}
147 	argc -= optind;
148 	argv += optind;
149 
150 	if (argc < 1)
151 		usage((char *)NULL);
152 
153 	if (killflg + doreboot + dohalt + dopower > 1)
154 		usage("incompatible switches -h, -k, -p and -r");
155 
156 	if (oflag && !(dohalt || dopower || doreboot))
157 		usage("-o requires -h, -p or -r");
158 
159 	if (nosync != NULL && !oflag)
160 		usage("-n requires -o");
161 
162 	getoffset(*argv++);
163 
164 	if (*argv) {
165 		for (p = mbuf, len = sizeof(mbuf); *argv; ++argv) {
166 			arglen = strlen(*argv);
167 			if ((len -= arglen) <= 2)
168 				break;
169 			if (p != mbuf)
170 				*p++ = ' ';
171 			memmove(p, *argv, arglen);
172 			p += arglen;
173 		}
174 		*p = '\n';
175 		*++p = '\0';
176 	}
177 
178 	if (readstdin) {
179 		p = mbuf;
180 		endp = mbuf + sizeof(mbuf) - 2;
181 		for (;;) {
182 			if (!fgets(p, endp - p + 1, stdin))
183 				break;
184 			for (; *p &&  p < endp; ++p);
185 			if (p == endp) {
186 				*p = '\n';
187 				*++p = '\0';
188 				break;
189 			}
190 		}
191 	}
192 	mbuflen = strlen(mbuf);
193 
194 	if (offset)
195 		(void)printf("Shutdown at %.24s.\n", ctime(&shuttime));
196 	else
197 		(void)printf("Shutdown NOW!\n");
198 
199 	if (!(whom = getlogin()))
200 		whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???";
201 
202 #ifdef DEBUG
203 	(void)putc('\n', stdout);
204 #else
205 	(void)setpriority(PRIO_PROCESS, 0, PRIO_MIN);
206 	{
207 		int forkpid;
208 
209 		forkpid = fork();
210 		if (forkpid == -1)
211 			err(1, "fork");
212 		if (forkpid)
213 			errx(0, "[pid %d]", forkpid);
214 	}
215 	setsid();
216 #endif
217 	openlog("shutdown", LOG_CONS, LOG_AUTH);
218 	loop();
219 	return(0);
220 }
221 
222 void
223 loop()
224 {
225 	struct interval *tp;
226 	u_int sltime;
227 	int logged;
228 
229 	if (offset <= NOLOG_TIME) {
230 		logged = 1;
231 		nolog();
232 	}
233 	else
234 		logged = 0;
235 	tp = tlist;
236 	if (tp->timeleft < offset)
237 		(void)sleep((u_int)(offset - tp->timeleft));
238 	else {
239 		while (tp->timeleft && offset < tp->timeleft)
240 			++tp;
241 		/*
242 		 * Warn now, if going to sleep more than a fifth of
243 		 * the next wait time.
244 		 */
245 		if ((sltime = offset - tp->timeleft)) {
246 			if (sltime > (u_int)(tp->timetowait / 5))
247 				timewarn(offset);
248 			(void)sleep(sltime);
249 		}
250 	}
251 	for (;; ++tp) {
252 		timewarn(tp->timeleft);
253 		if (!logged && tp->timeleft <= NOLOG_TIME) {
254 			logged = 1;
255 			nolog();
256 		}
257 		(void)sleep((u_int)tp->timetowait);
258 		if (!tp->timeleft)
259 			break;
260 	}
261 	die_you_gravy_sucking_pig_dog();
262 }
263 
264 static jmp_buf alarmbuf;
265 
266 static const char *restricted_environ[] = {
267 	"PATH=" _PATH_STDPATH,
268 	NULL
269 };
270 
271 void
272 timewarn(int timeleft)
273 {
274 	static int first;
275 	static char hostname[MAXHOSTNAMELEN + 1];
276 	FILE *pf;
277 	char wcmd[MAXPATHLEN + 4];
278 
279 	if (!first++)
280 		(void)gethostname(hostname, sizeof(hostname));
281 
282 	/* undoc -n option to wall suppresses normal wall banner */
283 	(void)snprintf(wcmd, sizeof(wcmd), "%s -n", _PATH_WALL);
284 	environ = restricted_environ;
285 	if (!(pf = popen(wcmd, "w"))) {
286 		syslog(LOG_ERR, "shutdown: can't find %s: %m", _PATH_WALL);
287 		return;
288 	}
289 
290 	(void)fprintf(pf,
291 	    "\007*** %sSystem shutdown message from %s@%s ***\007\n",
292 	    timeleft ? "": "FINAL ", whom, hostname);
293 
294 	if (timeleft > 10*60)
295 		(void)fprintf(pf, "System going down at %5.5s\n\n",
296 		    ctime(&shuttime) + 11);
297 	else if (timeleft > 59)
298 		(void)fprintf(pf, "System going down in %d minute%s\n\n",
299 		    timeleft / 60, (timeleft > 60) ? "s" : "");
300 	else if (timeleft)
301 		(void)fprintf(pf, "System going down in 30 seconds\n\n");
302 	else
303 		(void)fprintf(pf, "System going down IMMEDIATELY\n\n");
304 
305 	if (mbuflen)
306 		(void)fwrite(mbuf, sizeof(*mbuf), mbuflen, pf);
307 
308 	/*
309 	 * play some games, just in case wall doesn't come back
310 	 * probably unnecessary, given that wall is careful.
311 	 */
312 	if (!setjmp(alarmbuf)) {
313 		(void)signal(SIGALRM, timeout);
314 		(void)alarm((u_int)30);
315 		(void)pclose(pf);
316 		(void)alarm((u_int)0);
317 		(void)signal(SIGALRM, SIG_DFL);
318 	}
319 }
320 
321 void
322 timeout(int signo __unused)
323 {
324 	longjmp(alarmbuf, 1);
325 }
326 
327 void
328 die_you_gravy_sucking_pig_dog()
329 {
330 	char *empty_environ[] = { NULL };
331 
332 	syslog(LOG_NOTICE, "%s by %s: %s",
333 	    doreboot ? "reboot" : dohalt ? "halt" : dopower ? "power-down" :
334 	    "shutdown", whom, mbuf);
335 	(void)sleep(2);
336 
337 	(void)printf("\r\nSystem shutdown time has arrived\007\007\r\n");
338 	if (killflg) {
339 		(void)printf("\rbut you'll have to do it yourself\r\n");
340 		exit(0);
341 	}
342 #ifdef DEBUG
343 	if (doreboot)
344 		(void)printf("reboot");
345 	else if (dohalt)
346 		(void)printf("halt");
347 	else if (dopower)
348 		(void)printf("power-down");
349 	if (nosync != NULL)
350 		(void)printf(" no sync");
351 	(void)printf("\nkill -HUP 1\n");
352 #else
353 	if (!oflag) {
354 		(void)kill(1, doreboot ? SIGINT :	/* reboot */
355 			      dohalt ? SIGUSR1 :	/* halt */
356 			      dopower ? SIGUSR2 :	/* power-down */
357 			      SIGTERM);			/* single-user */
358 	} else {
359 		if (doreboot) {
360 			execle(_PATH_REBOOT, "reboot", "-l", nosync,
361 				(char *)NULL, empty_environ);
362 			syslog(LOG_ERR, "shutdown: can't exec %s: %m.",
363 				_PATH_REBOOT);
364 			warn(_PATH_REBOOT);
365 		}
366 		else if (dohalt) {
367 			execle(_PATH_HALT, "halt", "-l", nosync,
368 				(char *)NULL, empty_environ);
369 			syslog(LOG_ERR, "shutdown: can't exec %s: %m.",
370 				_PATH_HALT);
371 			warn(_PATH_HALT);
372 		}
373 		else if (dopower) {
374 			execle(_PATH_HALT, "halt", "-l", "-p", 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 		(void)kill(1, SIGTERM);		/* to single-user */
381 	}
382 #endif
383 	finish(0);
384 }
385 
386 #define	ATOI2(p)	(p[0] - '0') * 10 + (p[1] - '0'); p += 2;
387 
388 void
389 getoffset(char *timearg)
390 {
391 	struct tm *lt;
392 	char *p;
393 	time_t now;
394 	int this_year;
395 
396 	(void)time(&now);
397 
398 	if (!strcasecmp(timearg, "now")) {		/* now */
399 		offset = 0;
400 		shuttime = now;
401 		return;
402 	}
403 
404 	if (*timearg == '+') {				/* +minutes */
405 		if (!isdigit(*++timearg))
406 			badtime();
407 		if ((offset = atoi(timearg) * 60) < 0)
408 			badtime();
409 		shuttime = now + offset;
410 		return;
411 	}
412 
413 	/* handle hh:mm by getting rid of the colon */
414 	for (p = timearg; *p; ++p)
415 		if (!isascii(*p) || !isdigit(*p)) {
416 			if (*p == ':' && strlen(p) == 3) {
417 				p[0] = p[1];
418 				p[1] = p[2];
419 				p[2] = '\0';
420 			}
421 			else
422 				badtime();
423 		}
424 
425 	unsetenv("TZ");					/* OUR timezone */
426 	lt = localtime(&now);				/* current time val */
427 
428 	switch(strlen(timearg)) {
429 	case 10:
430 		this_year = lt->tm_year;
431 		lt->tm_year = ATOI2(timearg);
432 		/*
433 		 * check if the specified year is in the next century.
434 		 * allow for one year of user error as many people will
435 		 * enter n - 1 at the start of year n.
436 		 */
437 		if (lt->tm_year < (this_year % 100) - 1)
438 			lt->tm_year += 100;
439 		/* adjust for the year 2000 and beyond */
440 		lt->tm_year += (this_year - (this_year % 100));
441 		/* FALLTHROUGH */
442 	case 8:
443 		lt->tm_mon = ATOI2(timearg);
444 		if (--lt->tm_mon < 0 || lt->tm_mon > 11)
445 			badtime();
446 		/* FALLTHROUGH */
447 	case 6:
448 		lt->tm_mday = ATOI2(timearg);
449 		if (lt->tm_mday < 1 || lt->tm_mday > 31)
450 			badtime();
451 		/* FALLTHROUGH */
452 	case 4:
453 		lt->tm_hour = ATOI2(timearg);
454 		if (lt->tm_hour < 0 || lt->tm_hour > 23)
455 			badtime();
456 		lt->tm_min = ATOI2(timearg);
457 		if (lt->tm_min < 0 || lt->tm_min > 59)
458 			badtime();
459 		lt->tm_sec = 0;
460 		if ((shuttime = mktime(lt)) == -1)
461 			badtime();
462 		if ((offset = shuttime - now) < 0)
463 			errx(1, "that time is already past.");
464 		break;
465 	default:
466 		badtime();
467 	}
468 }
469 
470 #define	NOMSG	"\n\nNO LOGINS: System going down at "
471 void
472 nolog()
473 {
474 	int logfd;
475 	char *ct;
476 
477 	(void)unlink(_PATH_NOLOGIN);	/* in case linked to another file */
478 	(void)signal(SIGINT, finish);
479 	(void)signal(SIGHUP, finish);
480 	(void)signal(SIGQUIT, finish);
481 	(void)signal(SIGTERM, finish);
482 	if ((logfd = open(_PATH_NOLOGIN, O_WRONLY|O_CREAT|O_TRUNC,
483 	    0664)) >= 0) {
484 		(void)write(logfd, NOMSG, sizeof(NOMSG) - 1);
485 		ct = ctime(&shuttime);
486 		(void)write(logfd, ct + 11, 5);
487 		(void)write(logfd, "\n\n", 2);
488 		(void)write(logfd, mbuf, strlen(mbuf));
489 		(void)close(logfd);
490 	}
491 }
492 
493 void
494 finish(int signo __unused)
495 {
496 	if (!killflg)
497 		(void)unlink(_PATH_NOLOGIN);
498 	exit(0);
499 }
500 
501 void
502 badtime()
503 {
504 	errx(1, "bad time format");
505 }
506 
507 void
508 usage(const char *cp)
509 {
510 	if (cp != NULL)
511 		warnx("%s", cp);
512 	(void)fprintf(stderr,
513 	    "usage: shutdown [-] [-h | -p | -r | -k] [-o [-n]]"
514 	    " time [warning-message ...]\n");
515 	exit(1);
516 }
517