xref: /dragonfly/sbin/shutdown/shutdown.c (revision 092c2dd1) 
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 <fcntl.h>
42 #include <pwd.h>
43 #include <setjmp.h>
44 #include <signal.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <string.h>
48 #include <unistd.h>
49 
50 #include "pathnames.h"
51 
52 #ifdef DEBUG
53 #undef _PATH_NOLOGIN
54 #define	_PATH_NOLOGIN	"./nologin"
55 #endif
56 
57 #define	H		*60*60
58 #define	M		*60
59 #define	S		*1
60 #define	NOLOG_TIME	5*60
61 static struct interval {
62 	int timeleft, timetowait;
63 } tlist[] = {
64 	{ 10 H,  5 H },
65 	{  5 H,  3 H },
66 	{  2 H,  1 H },
67 	{  1 H, 30 M },
68 	{ 30 M, 10 M },
69 	{ 20 M, 10 M },
70 	{ 10 M,  5 M },
71 	{  5 M,  3 M },
72 	{  2 M,  1 M },
73 	{  1 M, 30 S },
74 	{ 30 S, 30 S },
75 	{  0  ,  0   }
76 };
77 #undef H
78 #undef M
79 #undef S
80 
81 static time_t offset, shuttime;
82 static int dohalt, dopower, doreboot, killflg, mbuflen, oflag;
83 static char mbuf[BUFSIZ];
84 static const char *nosync, *whom;
85 
86 static void badtime(void);
87 static void die_you_gravy_sucking_pig_dog(void);
88 static void finish(int);
89 static void getoffset(char *);
90 static void loop(void);
91 static void nolog(void);
92 static void timeout(int);
93 static void timewarn(int);
94 static void usage(const char *);
95 
96 extern const char **environ;
97 
98 int
99 main(int argc, char **argv)
100 {
101 	char *p, *endp;
102 	struct passwd *pw;
103 	int arglen, ch, len, readstdin;
104 
105 #ifndef DEBUG
106 	if (geteuid())
107 		errx(1, "NOT super-user");
108 #endif
109 
110 	nosync = NULL;
111 	readstdin = 0;
112 
113 	/*
114 	 * Test for the special case where the utility is called as
115 	 * "poweroff", for which it runs 'shutdown -p now'.
116 	 */
117 	if ((p = strrchr(argv[0], '/')) == NULL)
118 		p = argv[0];
119 	else
120 		++p;
121 	if (strcmp(p, "poweroff") == 0) {
122 		if (getopt(argc, argv, "") != -1)
123 			usage(NULL);
124 		argc -= optind;
125 		argv += optind;
126 		if (argc != 0)
127 			usage(NULL);
128 		dopower = 1;
129 		offset = 0;
130 		(void)time(&shuttime);
131 		goto poweroff;
132 	}
133 
134 	while ((ch = getopt(argc, argv, "-hknopr")) != -1)
135 		switch (ch) {
136 		case '-':
137 			readstdin = 1;
138 			break;
139 		case 'h':
140 			dohalt = 1;
141 			break;
142 		case 'k':
143 			killflg = 1;
144 			break;
145 		case 'n':
146 			nosync = "-n";
147 			break;
148 		case 'o':
149 			oflag = 1;
150 			break;
151 		case 'p':
152 			dopower = 1;
153 			break;
154 		case 'r':
155 			doreboot = 1;
156 			break;
157 		case '?':
158 		default:
159 			usage(NULL);
160 		}
161 	argc -= optind;
162 	argv += optind;
163 
164 	if (argc < 1)
165 		usage(NULL);
166 
167 	if (killflg + doreboot + dohalt + dopower > 1)
168 		usage("incompatible switches -h, -k, -p and -r");
169 
170 	if (oflag && !(dohalt || dopower || doreboot))
171 		usage("-o requires -h, -p or -r");
172 
173 	if (nosync != NULL && !oflag)
174 		usage("-n requires -o");
175 
176 	getoffset(*argv++);
177 
178 poweroff:
179 	if (*argv) {
180 		for (p = mbuf, len = sizeof(mbuf); *argv; ++argv) {
181 			arglen = strlen(*argv);
182 			if ((len -= arglen) <= 2)
183 				break;
184 			if (p != mbuf)
185 				*p++ = ' ';
186 			memmove(p, *argv, arglen);
187 			p += arglen;
188 		}
189 		*p = '\n';
190 		*++p = '\0';
191 	}
192 
193 	if (readstdin) {
194 		p = mbuf;
195 		endp = mbuf + sizeof(mbuf) - 2;
196 		for (;;) {
197 			if (!fgets(p, endp - p + 1, stdin))
198 				break;
199 			for (; *p &&  p < endp; ++p);
200 			if (p == endp) {
201 				*p = '\n';
202 				*++p = '\0';
203 				break;
204 			}
205 		}
206 	}
207 	mbuflen = strlen(mbuf);
208 
209 	if (offset)
210 		printf("Shutdown at %.24s.\n", ctime(&shuttime));
211 	else
212 		printf("Shutdown NOW!\n");
213 
214 	if (!(whom = getlogin()))
215 		whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???";
216 
217 #ifdef DEBUG
218 	putc('\n', stdout);
219 #else
220 	setpriority(PRIO_PROCESS, 0, PRIO_MIN);
221 	{
222 		int forkpid;
223 
224 		forkpid = fork();
225 		if (forkpid == -1)
226 			err(1, "fork");
227 		if (forkpid)
228 			errx(0, "[pid %d]", forkpid);
229 	}
230 	setsid();
231 #endif
232 	openlog("shutdown", LOG_CONS, LOG_AUTH);
233 	loop();
234 	return(0);
235 }
236 
237 static void
238 loop(void)
239 {
240 	struct interval *tp;
241 	u_int sltime;
242 	int logged;
243 
244 	if (offset <= NOLOG_TIME) {
245 		logged = 1;
246 		nolog();
247 	}
248 	else
249 		logged = 0;
250 	tp = tlist;
251 	if (tp->timeleft < offset)
252 		sleep((u_int)(offset - tp->timeleft));
253 	else {
254 		while (tp->timeleft && offset < tp->timeleft)
255 			++tp;
256 		/*
257 		 * Warn now, if going to sleep more than a fifth of
258 		 * the next wait time.
259 		 */
260 		if ((sltime = offset - tp->timeleft)) {
261 			if (sltime > (u_int)(tp->timetowait / 5))
262 				timewarn(offset);
263 			sleep(sltime);
264 		}
265 	}
266 	for (;; ++tp) {
267 		timewarn(tp->timeleft);
268 		if (!logged && tp->timeleft <= NOLOG_TIME) {
269 			logged = 1;
270 			nolog();
271 		}
272 		sleep((u_int)tp->timetowait);
273 		if (!tp->timeleft)
274 			break;
275 	}
276 	die_you_gravy_sucking_pig_dog();
277 }
278 
279 static jmp_buf alarmbuf;
280 
281 static const char *restricted_environ[] = {
282 	"PATH=" _PATH_STDPATH,
283 	NULL
284 };
285 
286 static void
287 timewarn(int timeleft)
288 {
289 	static int first;
290 	static char hostname[MAXHOSTNAMELEN + 1];
291 	FILE *pf;
292 	char wcmd[MAXPATHLEN + 4];
293 
294 	if (!first++)
295 		gethostname(hostname, sizeof(hostname));
296 
297 	/* undoc -n option to wall suppresses normal wall banner */
298 	snprintf(wcmd, sizeof(wcmd), "%s -n", _PATH_WALL);
299 	environ = restricted_environ;
300 	if (!(pf = popen(wcmd, "w"))) {
301 		syslog(LOG_ERR, "shutdown: can't find %s: %m", _PATH_WALL);
302 		return;
303 	}
304 
305 	fprintf(pf,
306 	    "\007*** %sSystem shutdown message from %s@%s ***\007\n",
307 	    timeleft ? "": "FINAL ", whom, hostname);
308 
309 	if (timeleft > 10*60)
310 		fprintf(pf, "System going down at %5.5s\n\n",
311 		    ctime(&shuttime) + 11);
312 	else if (timeleft > 59)
313 		fprintf(pf, "System going down in %d minute%s\n\n",
314 		    timeleft / 60, (timeleft > 60) ? "s" : "");
315 	else if (timeleft)
316 		fprintf(pf, "System going down in 30 seconds\n\n");
317 	else
318 		fprintf(pf, "System going down IMMEDIATELY\n\n");
319 
320 	if (mbuflen)
321 		fwrite(mbuf, sizeof(*mbuf), mbuflen, pf);
322 
323 	/*
324 	 * play some games, just in case wall doesn't come back
325 	 * probably unnecessary, given that wall is careful.
326 	 */
327 	if (!setjmp(alarmbuf)) {
328 		signal(SIGALRM, timeout);
329 		alarm((u_int)30);
330 		pclose(pf);
331 		alarm((u_int)0);
332 		signal(SIGALRM, SIG_DFL);
333 	}
334 }
335 
336 static void
337 timeout(int signo __unused)
338 {
339 	longjmp(alarmbuf, 1);
340 }
341 
342 static void
343 die_you_gravy_sucking_pig_dog(void)
344 {
345 #ifndef DEBUG
346 	char *empty_environ[] = { NULL };
347 #endif
348 
349 	syslog(LOG_NOTICE, "%s by %s: %s",
350 	    doreboot ? "reboot" : dohalt ? "halt" : dopower ? "power-down" :
351 	    "shutdown", whom, mbuf);
352 	sleep(2);
353 
354 	printf("\r\nSystem shutdown time has arrived\007\007\r\n");
355 	if (killflg) {
356 		printf("\rbut you'll have to do it yourself\r\n");
357 		exit(0);
358 	}
359 #ifdef DEBUG
360 	if (doreboot)
361 		printf("reboot");
362 	else if (dohalt)
363 		printf("halt");
364 	else if (dopower)
365 		printf("power-down");
366 	if (nosync != NULL)
367 		printf(" no sync");
368 	printf("\nkill -HUP 1\n");
369 #else
370 	if (!oflag) {
371 		kill(1, doreboot ? SIGINT :	/* reboot */
372 			dohalt ? SIGUSR1 :	/* halt */
373 			dopower ? SIGUSR2 :	/* power-down */
374 			SIGTERM);		/* single-user */
375 	} else {
376 		if (doreboot) {
377 			execle(_PATH_REBOOT, "reboot", "-l", nosync,
378 				NULL, empty_environ);
379 			syslog(LOG_ERR, "shutdown: can't exec %s: %m.",
380 				_PATH_REBOOT);
381 			warn(_PATH_REBOOT);
382 		}
383 		else if (dohalt) {
384 			execle(_PATH_HALT, "halt", "-l", nosync,
385 				NULL, empty_environ);
386 			syslog(LOG_ERR, "shutdown: can't exec %s: %m.",
387 				_PATH_HALT);
388 			warn(_PATH_HALT);
389 		}
390 		else if (dopower) {
391 			execle(_PATH_HALT, "halt", "-l", "-p", nosync,
392 				NULL, empty_environ);
393 			syslog(LOG_ERR, "shutdown: can't exec %s: %m.",
394 				_PATH_HALT);
395 			warn(_PATH_HALT);
396 		}
397 		kill(1, SIGTERM);		/* to single-user */
398 	}
399 #endif
400 	finish(0);
401 }
402 
403 #define	ATOI2(p)	(p[0] - '0') * 10 + (p[1] - '0'); p += 2;
404 
405 static void
406 getoffset(char *timearg)
407 {
408 	struct tm *lt;
409 	char *p;
410 	time_t now;
411 	int this_year;
412 
413 	time(&now);
414 
415 	if (!strcasecmp(timearg, "now")) {		/* now */
416 		offset = 0;
417 		shuttime = now;
418 		return;
419 	}
420 
421 	if (*timearg == '+') {				/* +minutes */
422 		if (!isdigit(*++timearg))
423 			badtime();
424 		if ((offset = atoi(timearg) * 60) < 0)
425 			badtime();
426 		shuttime = now + offset;
427 		return;
428 	}
429 
430 	/* handle hh:mm by getting rid of the colon */
431 	for (p = timearg; *p; ++p)
432 		if (!isascii(*p) || !isdigit(*p)) {
433 			if (*p == ':' && strlen(p) == 3) {
434 				p[0] = p[1];
435 				p[1] = p[2];
436 				p[2] = '\0';
437 			}
438 			else
439 				badtime();
440 		}
441 
442 	unsetenv("TZ");					/* OUR timezone */
443 	lt = localtime(&now);				/* current time val */
444 
445 	switch(strlen(timearg)) {
446 	case 10:
447 		this_year = lt->tm_year;
448 		lt->tm_year = ATOI2(timearg);
449 		/*
450 		 * check if the specified year is in the next century.
451 		 * allow for one year of user error as many people will
452 		 * enter n - 1 at the start of year n.
453 		 */
454 		if (lt->tm_year < (this_year % 100) - 1)
455 			lt->tm_year += 100;
456 		/* adjust for the year 2000 and beyond */
457 		lt->tm_year += (this_year - (this_year % 100));
458 		/* FALLTHROUGH */
459 	case 8:
460 		lt->tm_mon = ATOI2(timearg);
461 		if (--lt->tm_mon < 0 || lt->tm_mon > 11)
462 			badtime();
463 		/* FALLTHROUGH */
464 	case 6:
465 		lt->tm_mday = ATOI2(timearg);
466 		if (lt->tm_mday < 1 || lt->tm_mday > 31)
467 			badtime();
468 		/* FALLTHROUGH */
469 	case 4:
470 		lt->tm_hour = ATOI2(timearg);
471 		if (lt->tm_hour < 0 || lt->tm_hour > 23)
472 			badtime();
473 		lt->tm_min = ATOI2(timearg);
474 		if (lt->tm_min < 0 || lt->tm_min > 59)
475 			badtime();
476 		lt->tm_sec = 0;
477 		if ((shuttime = mktime(lt)) == -1)
478 			badtime();
479 		if ((offset = shuttime - now) < 0)
480 			errx(1, "that time is already past.");
481 		break;
482 	default:
483 		badtime();
484 	}
485 }
486 
487 #define	NOMSG	"\n\nNO LOGINS: System going down at "
488 static void
489 nolog(void)
490 {
491 	int logfd;
492 	char *ct;
493 
494 	unlink(_PATH_NOLOGIN);	/* in case linked to another file */
495 	signal(SIGINT, finish);
496 	signal(SIGHUP, finish);
497 	signal(SIGQUIT, finish);
498 	signal(SIGTERM, finish);
499 	if ((logfd = open(_PATH_NOLOGIN, O_WRONLY|O_CREAT|O_TRUNC,
500 	    0664)) >= 0) {
501 		write(logfd, NOMSG, sizeof(NOMSG) - 1);
502 		ct = ctime(&shuttime);
503 		write(logfd, ct + 11, 5);
504 		write(logfd, "\n\n", 2);
505 		write(logfd, mbuf, strlen(mbuf));
506 		close(logfd);
507 	}
508 }
509 
510 static void
511 finish(int signo __unused)
512 {
513 	if (!killflg)
514 		unlink(_PATH_NOLOGIN);
515 	exit(0);
516 }
517 
518 static void
519 badtime(void)
520 {
521 	errx(1, "bad time format");
522 }
523 
524 static void
525 usage(const char *cp)
526 {
527 	if (cp != NULL)
528 		warnx("%s", cp);
529 	fprintf(stderr,
530 	    "usage: shutdown [-] [-h | -p | -r | -k] [-o [-n]]"
531 	    " time [warning-message ...]\n"
532 	    "       poweroff\n");
533 	exit(1);
534 }
535