xref: /dragonfly/sbin/shutdown/shutdown.c (revision dc71b7ab) 
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  * $DragonFly: src/sbin/shutdown/shutdown.c,v 1.6 2005/01/02 01:22:49 cpressey Exp $
33  */
34 
35 #include <sys/param.h>
36 #include <sys/time.h>
37 #include <sys/resource.h>
38 #include <sys/syslog.h>
39 
40 #include <ctype.h>
41 #include <err.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 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 void badtime(void);
88 void die_you_gravy_sucking_pig_dog(void);
89 void finish(int);
90 void getoffset(char *);
91 void loop(void);
92 void nolog(void);
93 void timeout(int);
94 void timewarn(int);
95 void usage(const char *);
96 
97 int
98 main(int argc, char **argv)
99 {
100 	char *p, *endp;
101 	struct passwd *pw;
102 	int arglen, ch, len, readstdin;
103 
104 #ifndef DEBUG
105 	if (geteuid())
106 		errx(1, "NOT super-user");
107 #endif
108 	nosync = NULL;
109 	readstdin = 0;
110 	while ((ch = getopt(argc, argv, "-hknopr")) != -1)
111 		switch (ch) {
112 		case '-':
113 			readstdin = 1;
114 			break;
115 		case 'h':
116 			dohalt = 1;
117 			break;
118 		case 'k':
119 			killflg = 1;
120 			break;
121 		case 'n':
122 			nosync = "-n";
123 			break;
124 		case 'o':
125 			oflag = 1;
126 			break;
127 		case 'p':
128 			dopower = 1;
129 			break;
130 		case 'r':
131 			doreboot = 1;
132 			break;
133 		case '?':
134 		default:
135 			usage(NULL);
136 		}
137 	argc -= optind;
138 	argv += optind;
139 
140 	if (argc < 1)
141 		usage(NULL);
142 
143 	if (killflg + doreboot + dohalt + dopower > 1)
144 		usage("incompatible switches -h, -k, -p and -r");
145 
146 	if (oflag && !(dohalt || dopower || doreboot))
147 		usage("-o requires -h, -p or -r");
148 
149 	if (nosync != NULL && !oflag)
150 		usage("-n requires -o");
151 
152 	getoffset(*argv++);
153 
154 	if (*argv) {
155 		for (p = mbuf, len = sizeof(mbuf); *argv; ++argv) {
156 			arglen = strlen(*argv);
157 			if ((len -= arglen) <= 2)
158 				break;
159 			if (p != mbuf)
160 				*p++ = ' ';
161 			memmove(p, *argv, arglen);
162 			p += arglen;
163 		}
164 		*p = '\n';
165 		*++p = '\0';
166 	}
167 
168 	if (readstdin) {
169 		p = mbuf;
170 		endp = mbuf + sizeof(mbuf) - 2;
171 		for (;;) {
172 			if (!fgets(p, endp - p + 1, stdin))
173 				break;
174 			for (; *p &&  p < endp; ++p);
175 			if (p == endp) {
176 				*p = '\n';
177 				*++p = '\0';
178 				break;
179 			}
180 		}
181 	}
182 	mbuflen = strlen(mbuf);
183 
184 	if (offset)
185 		printf("Shutdown at %.24s.\n", ctime(&shuttime));
186 	else
187 		printf("Shutdown NOW!\n");
188 
189 	if (!(whom = getlogin()))
190 		whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???";
191 
192 #ifdef DEBUG
193 	putc('\n', stdout);
194 #else
195 	setpriority(PRIO_PROCESS, 0, PRIO_MIN);
196 	{
197 		int forkpid;
198 
199 		forkpid = fork();
200 		if (forkpid == -1)
201 			err(1, "fork");
202 		if (forkpid)
203 			errx(0, "[pid %d]", forkpid);
204 	}
205 	setsid();
206 #endif
207 	openlog("shutdown", LOG_CONS, LOG_AUTH);
208 	loop();
209 	return(0);
210 }
211 
212 void
213 loop(void)
214 {
215 	struct interval *tp;
216 	u_int sltime;
217 	int logged;
218 
219 	if (offset <= NOLOG_TIME) {
220 		logged = 1;
221 		nolog();
222 	}
223 	else
224 		logged = 0;
225 	tp = tlist;
226 	if (tp->timeleft < offset)
227 		sleep((u_int)(offset - tp->timeleft));
228 	else {
229 		while (tp->timeleft && offset < tp->timeleft)
230 			++tp;
231 		/*
232 		 * Warn now, if going to sleep more than a fifth of
233 		 * the next wait time.
234 		 */
235 		if ((sltime = offset - tp->timeleft)) {
236 			if (sltime > (u_int)(tp->timetowait / 5))
237 				timewarn(offset);
238 			sleep(sltime);
239 		}
240 	}
241 	for (;; ++tp) {
242 		timewarn(tp->timeleft);
243 		if (!logged && tp->timeleft <= NOLOG_TIME) {
244 			logged = 1;
245 			nolog();
246 		}
247 		sleep((u_int)tp->timetowait);
248 		if (!tp->timeleft)
249 			break;
250 	}
251 	die_you_gravy_sucking_pig_dog();
252 }
253 
254 static jmp_buf alarmbuf;
255 
256 static const char *restricted_environ[] = {
257 	"PATH=" _PATH_STDPATH,
258 	NULL
259 };
260 
261 extern const char **environ;
262 
263 void
264 timewarn(int timeleft)
265 {
266 	static int first;
267 	static char hostname[MAXHOSTNAMELEN + 1];
268 	FILE *pf;
269 	char wcmd[MAXPATHLEN + 4];
270 
271 	if (!first++)
272 		gethostname(hostname, sizeof(hostname));
273 
274 	/* undoc -n option to wall suppresses normal wall banner */
275 	snprintf(wcmd, sizeof(wcmd), "%s -n", _PATH_WALL);
276 	environ = restricted_environ;
277 	if (!(pf = popen(wcmd, "w"))) {
278 		syslog(LOG_ERR, "shutdown: can't find %s: %m", _PATH_WALL);
279 		return;
280 	}
281 
282 	fprintf(pf,
283 	    "\007*** %sSystem shutdown message from %s@%s ***\007\n",
284 	    timeleft ? "": "FINAL ", whom, hostname);
285 
286 	if (timeleft > 10*60)
287 		fprintf(pf, "System going down at %5.5s\n\n",
288 		    ctime(&shuttime) + 11);
289 	else if (timeleft > 59)
290 		fprintf(pf, "System going down in %d minute%s\n\n",
291 		    timeleft / 60, (timeleft > 60) ? "s" : "");
292 	else if (timeleft)
293 		fprintf(pf, "System going down in 30 seconds\n\n");
294 	else
295 		fprintf(pf, "System going down IMMEDIATELY\n\n");
296 
297 	if (mbuflen)
298 		fwrite(mbuf, sizeof(*mbuf), mbuflen, pf);
299 
300 	/*
301 	 * play some games, just in case wall doesn't come back
302 	 * probably unnecessary, given that wall is careful.
303 	 */
304 	if (!setjmp(alarmbuf)) {
305 		signal(SIGALRM, timeout);
306 		alarm((u_int)30);
307 		pclose(pf);
308 		alarm((u_int)0);
309 		signal(SIGALRM, SIG_DFL);
310 	}
311 }
312 
313 void
314 timeout(int signo __unused)
315 {
316 	longjmp(alarmbuf, 1);
317 }
318 
319 void
320 die_you_gravy_sucking_pig_dog(void)
321 {
322 	char *empty_environ[] = { NULL };
323 
324 	syslog(LOG_NOTICE, "%s by %s: %s",
325 	    doreboot ? "reboot" : dohalt ? "halt" : dopower ? "power-down" :
326 	    "shutdown", whom, mbuf);
327 	sleep(2);
328 
329 	printf("\r\nSystem shutdown time has arrived\007\007\r\n");
330 	if (killflg) {
331 		printf("\rbut you'll have to do it yourself\r\n");
332 		exit(0);
333 	}
334 #ifdef DEBUG
335 	if (doreboot)
336 		printf("reboot");
337 	else if (dohalt)
338 		printf("halt");
339 	else if (dopower)
340 		printf("power-down");
341 	if (nosync != NULL)
342 		printf(" no sync");
343 	printf("\nkill -HUP 1\n");
344 #else
345 	if (!oflag) {
346 		kill(1, doreboot ? SIGINT :	/* reboot */
347 			dohalt ? SIGUSR1 :	/* halt */
348 			dopower ? SIGUSR2 :	/* power-down */
349 			SIGTERM);		/* single-user */
350 	} else {
351 		if (doreboot) {
352 			execle(_PATH_REBOOT, "reboot", "-l", nosync,
353 				NULL, empty_environ);
354 			syslog(LOG_ERR, "shutdown: can't exec %s: %m.",
355 				_PATH_REBOOT);
356 			warn(_PATH_REBOOT);
357 		}
358 		else if (dohalt) {
359 			execle(_PATH_HALT, "halt", "-l", nosync,
360 				NULL, empty_environ);
361 			syslog(LOG_ERR, "shutdown: can't exec %s: %m.",
362 				_PATH_HALT);
363 			warn(_PATH_HALT);
364 		}
365 		else if (dopower) {
366 			execle(_PATH_HALT, "halt", "-l", "-p", nosync,
367 				NULL, empty_environ);
368 			syslog(LOG_ERR, "shutdown: can't exec %s: %m.",
369 				_PATH_HALT);
370 			warn(_PATH_HALT);
371 		}
372 		kill(1, SIGTERM);		/* to single-user */
373 	}
374 #endif
375 	finish(0);
376 }
377 
378 #define	ATOI2(p)	(p[0] - '0') * 10 + (p[1] - '0'); p += 2;
379 
380 void
381 getoffset(char *timearg)
382 {
383 	struct tm *lt;
384 	char *p;
385 	time_t now;
386 	int this_year;
387 
388 	time(&now);
389 
390 	if (!strcasecmp(timearg, "now")) {		/* now */
391 		offset = 0;
392 		shuttime = now;
393 		return;
394 	}
395 
396 	if (*timearg == '+') {				/* +minutes */
397 		if (!isdigit(*++timearg))
398 			badtime();
399 		if ((offset = atoi(timearg) * 60) < 0)
400 			badtime();
401 		shuttime = now + offset;
402 		return;
403 	}
404 
405 	/* handle hh:mm by getting rid of the colon */
406 	for (p = timearg; *p; ++p)
407 		if (!isascii(*p) || !isdigit(*p)) {
408 			if (*p == ':' && strlen(p) == 3) {
409 				p[0] = p[1];
410 				p[1] = p[2];
411 				p[2] = '\0';
412 			}
413 			else
414 				badtime();
415 		}
416 
417 	unsetenv("TZ");					/* OUR timezone */
418 	lt = localtime(&now);				/* current time val */
419 
420 	switch(strlen(timearg)) {
421 	case 10:
422 		this_year = lt->tm_year;
423 		lt->tm_year = ATOI2(timearg);
424 		/*
425 		 * check if the specified year is in the next century.
426 		 * allow for one year of user error as many people will
427 		 * enter n - 1 at the start of year n.
428 		 */
429 		if (lt->tm_year < (this_year % 100) - 1)
430 			lt->tm_year += 100;
431 		/* adjust for the year 2000 and beyond */
432 		lt->tm_year += (this_year - (this_year % 100));
433 		/* FALLTHROUGH */
434 	case 8:
435 		lt->tm_mon = ATOI2(timearg);
436 		if (--lt->tm_mon < 0 || lt->tm_mon > 11)
437 			badtime();
438 		/* FALLTHROUGH */
439 	case 6:
440 		lt->tm_mday = ATOI2(timearg);
441 		if (lt->tm_mday < 1 || lt->tm_mday > 31)
442 			badtime();
443 		/* FALLTHROUGH */
444 	case 4:
445 		lt->tm_hour = ATOI2(timearg);
446 		if (lt->tm_hour < 0 || lt->tm_hour > 23)
447 			badtime();
448 		lt->tm_min = ATOI2(timearg);
449 		if (lt->tm_min < 0 || lt->tm_min > 59)
450 			badtime();
451 		lt->tm_sec = 0;
452 		if ((shuttime = mktime(lt)) == -1)
453 			badtime();
454 		if ((offset = shuttime - now) < 0)
455 			errx(1, "that time is already past.");
456 		break;
457 	default:
458 		badtime();
459 	}
460 }
461 
462 #define	NOMSG	"\n\nNO LOGINS: System going down at "
463 void
464 nolog(void)
465 {
466 	int logfd;
467 	char *ct;
468 
469 	unlink(_PATH_NOLOGIN);	/* in case linked to another file */
470 	signal(SIGINT, finish);
471 	signal(SIGHUP, finish);
472 	signal(SIGQUIT, finish);
473 	signal(SIGTERM, finish);
474 	if ((logfd = open(_PATH_NOLOGIN, O_WRONLY|O_CREAT|O_TRUNC,
475 	    0664)) >= 0) {
476 		write(logfd, NOMSG, sizeof(NOMSG) - 1);
477 		ct = ctime(&shuttime);
478 		write(logfd, ct + 11, 5);
479 		write(logfd, "\n\n", 2);
480 		write(logfd, mbuf, strlen(mbuf));
481 		close(logfd);
482 	}
483 }
484 
485 void
486 finish(int signo __unused)
487 {
488 	if (!killflg)
489 		unlink(_PATH_NOLOGIN);
490 	exit(0);
491 }
492 
493 void
494 badtime(void)
495 {
496 	errx(1, "bad time format");
497 }
498 
499 void
500 usage(const char *cp)
501 {
502 	if (cp != NULL)
503 		warnx("%s", cp);
504 	fprintf(stderr,
505 	    "usage: shutdown [-] [-h | -p | -r | -k] [-o [-n]]"
506 	    " time [warning-message ...]\n");
507 	exit(1);
508 }
509