shutdown.c revision 32399 
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 *	$Id: shutdown.c,v 1.11 1998/01/08 20:05:45 alex Exp $
34 */
35
36#ifndef lint
37static char copyright[] =
38"@(#) Copyright (c) 1988, 1990, 1993\n\
39	The Regents of the University of California.  All rights reserved.\n";
40#endif /* not lint */
41
42#ifndef lint
43static char sccsid[] = "@(#)shutdown.c	8.2 (Berkeley) 2/16/94";
44#endif /* not lint */
45
46#include <sys/param.h>
47#include <sys/time.h>
48#include <sys/resource.h>
49#include <sys/syslog.h>
50
51#include <ctype.h>
52#include <fcntl.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#include <err.h>
61
62#include "pathnames.h"
63
64#ifdef DEBUG
65#undef _PATH_NOLOGIN
66#define	_PATH_NOLOGIN	"./nologin"
67#endif
68
69#define	H		*60*60
70#define	M		*60
71#define	S		*1
72#define	NOLOG_TIME	5*60
73struct interval {
74	int timeleft, timetowait;
75} tlist[] = {
76	{ 10 H,  5 H },
77	{  5 H,  3 H },
78	{  2 H,  1 H },
79	{  1 H, 30 M },
80	{ 30 M, 10 M },
81	{ 20 M, 10 M },
82	{ 10 M,  5 M },
83	{  5 M,  3 M },
84	{  2 M,  1 M },
85	{  1 M, 30 S },
86	{ 30 S, 30 S },
87	{  0  ,  0   }
88};
89#undef H
90#undef M
91#undef S
92
93static time_t offset, shuttime;
94static int dohalt, doreboot, killflg, mbuflen;
95static char *nosync, *whom, mbuf[BUFSIZ];
96
97void badtime __P((void));
98void die_you_gravy_sucking_pig_dog __P((void));
99void finish __P((int));
100void getoffset __P((char *));
101void loop __P((void));
102void nolog __P((void));
103void timeout __P((int));
104void timewarn __P((int));
105void usage __P((void));
106
107int
108main(argc, argv)
109	int argc;
110	char *argv[];
111{
112	extern int optind;
113	register char *p, *endp;
114	struct passwd *pw;
115	int arglen, ch, len, readstdin;
116
117#ifndef DEBUG
118	if (geteuid())
119		errx(1, "NOT super-user");
120#endif
121	nosync = NULL;
122	readstdin = 0;
123	while ((ch = getopt(argc, argv, "-hknr")) != -1)
124		switch (ch) {
125		case '-':
126			readstdin = 1;
127			break;
128		case 'h':
129			dohalt = 1;
130			break;
131		case 'k':
132			killflg = 1;
133			break;
134		case 'n':
135			nosync = "-n";
136			break;
137		case 'r':
138			doreboot = 1;
139			break;
140		case '?':
141		default:
142			usage();
143		}
144	argc -= optind;
145	argv += optind;
146
147	if (argc < 1)
148		usage();
149
150	if (doreboot && dohalt) {
151		warnx("incompatible switches -h and -r.");
152		usage();
153	}
154	getoffset(*argv++);
155
156	if (*argv) {
157		for (p = mbuf, len = sizeof(mbuf); *argv; ++argv) {
158			arglen = strlen(*argv);
159			if ((len -= arglen) <= 2)
160				break;
161			if (p != mbuf)
162				*p++ = ' ';
163			bcopy(*argv, p, arglen);
164			p += arglen;
165		}
166		*p = '\n';
167		*++p = '\0';
168	}
169
170	if (readstdin) {
171		p = mbuf;
172		endp = mbuf + sizeof(mbuf) - 2;
173		for (;;) {
174			if (!fgets(p, endp - p + 1, stdin))
175				break;
176			for (; *p &&  p < endp; ++p);
177			if (p == endp) {
178				*p = '\n';
179				*++p = '\0';
180				break;
181			}
182		}
183	}
184	mbuflen = strlen(mbuf);
185
186	if (offset)
187		(void)printf("Shutdown at %.24s.\n", ctime(&shuttime));
188	else
189		(void)printf("Shutdown NOW!\n");
190
191	if (!(whom = getlogin()))
192		whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???";
193
194#ifdef DEBUG
195	(void)putc('\n', stdout);
196#else
197	(void)setpriority(PRIO_PROCESS, 0, PRIO_MIN);
198	{
199		int forkpid;
200
201		forkpid = fork();
202		if (forkpid == -1)
203			err(1, "fork");
204		if (forkpid)
205			errx(0, "[pid %d]", forkpid);
206	}
207	setsid();
208#endif
209	openlog("shutdown", LOG_CONS, LOG_AUTH);
210	loop();
211	/* NOTREACHED */
212}
213
214void
215loop()
216{
217	struct interval *tp;
218	u_int sltime;
219	int logged;
220
221	if (offset <= NOLOG_TIME) {
222		logged = 1;
223		nolog();
224	}
225	else
226		logged = 0;
227	tp = tlist;
228	if (tp->timeleft < offset)
229		(void)sleep((u_int)(offset - tp->timeleft));
230	else {
231		while (offset < tp->timeleft)
232			++tp;
233		/*
234		 * Warn now, if going to sleep more than a fifth of
235		 * the next wait time.
236		 */
237		if ((sltime = offset - tp->timeleft)) {
238			if (sltime > tp->timetowait / 5)
239				timewarn(offset);
240			(void)sleep(sltime);
241		}
242	}
243	for (;; ++tp) {
244		timewarn(tp->timeleft);
245		if (!logged && tp->timeleft <= NOLOG_TIME) {
246			logged = 1;
247			nolog();
248		}
249		(void)sleep((u_int)tp->timetowait);
250		if (!tp->timeleft)
251			break;
252	}
253	die_you_gravy_sucking_pig_dog();
254}
255
256static jmp_buf alarmbuf;
257
258static char *restricted_environ[] = {
259	"PATH=" _PATH_STDPATH,
260	NULL
261};
262
263void
264timewarn(timeleft)
265	int timeleft;
266{
267	static int first;
268	static char hostname[MAXHOSTNAMELEN + 1];
269	FILE *pf;
270	char wcmd[MAXPATHLEN + 4];
271	extern char **environ;
272
273	if (!first++)
274		(void)gethostname(hostname, sizeof(hostname));
275
276	/* undoc -n option to wall suppresses normal wall banner */
277	(void)snprintf(wcmd, sizeof(wcmd), "%s -n", _PATH_WALL);
278	environ = restricted_environ;
279	if (!(pf = popen(wcmd, "w"))) {
280		syslog(LOG_ERR, "shutdown: can't find %s: %m", _PATH_WALL);
281		return;
282	}
283
284	(void)fprintf(pf,
285	    "\007*** %sSystem shutdown message from %s@%s ***\007\n",
286	    timeleft ? "": "FINAL ", whom, hostname);
287
288	if (timeleft > 10*60)
289		(void)fprintf(pf, "System going down at %5.5s\n\n",
290		    ctime(&shuttime) + 11);
291	else if (timeleft > 59)
292		(void)fprintf(pf, "System going down in %d minute%s\n\n",
293		    timeleft / 60, (timeleft > 60) ? "s" : "");
294	else if (timeleft)
295		(void)fprintf(pf, "System going down in 30 seconds\n\n");
296	else
297		(void)fprintf(pf, "System going down IMMEDIATELY\n\n");
298
299	if (mbuflen)
300		(void)fwrite(mbuf, sizeof(*mbuf), mbuflen, pf);
301
302	/*
303	 * play some games, just in case wall doesn't come back
304	 * probably unecessary, given that wall is careful.
305	 */
306	if (!setjmp(alarmbuf)) {
307		(void)signal(SIGALRM, timeout);
308		(void)alarm((u_int)30);
309		(void)pclose(pf);
310		(void)alarm((u_int)0);
311		(void)signal(SIGALRM, SIG_DFL);
312	}
313}
314
315void
316timeout(signo)
317	int signo;
318{
319	longjmp(alarmbuf, 1);
320}
321
322void
323die_you_gravy_sucking_pig_dog()
324{
325	char *empty_environ[] = { NULL };
326
327	syslog(LOG_NOTICE, "%s by %s: %s",
328	    doreboot ? "reboot" : dohalt ? "halt" : "shutdown", whom, mbuf);
329	(void)sleep(2);
330
331	(void)printf("\r\nSystem shutdown time has arrived\007\007\r\n");
332	if (killflg) {
333		(void)printf("\rbut you'll have to do it yourself\r\n");
334		exit(0);
335	}
336#ifdef DEBUG
337	if (doreboot)
338		(void)printf("reboot");
339	else if (dohalt)
340		(void)printf("halt");
341	if (nosync)
342		(void)printf(" no sync");
343	(void)printf("\nkill -HUP 1\n");
344#else
345	if (doreboot) {
346		execle(_PATH_REBOOT, "reboot", "-l", nosync,
347			   (char *)NULL, empty_environ);
348		syslog(LOG_ERR, "shutdown: can't exec %s: %m.", _PATH_REBOOT);
349		warn(_PATH_REBOOT);
350	}
351	else if (dohalt) {
352		execle(_PATH_HALT, "halt", "-l", nosync,
353			   (char *)NULL, empty_environ);
354		syslog(LOG_ERR, "shutdown: can't exec %s: %m.", _PATH_HALT);
355		warn(_PATH_HALT);
356	}
357	(void)kill(1, SIGTERM);		/* to single user */
358#endif
359	finish(0);
360}
361
362#define	ATOI2(p)	(p[0] - '0') * 10 + (p[1] - '0'); p += 2;
363
364void
365getoffset(timearg)
366	register char *timearg;
367{
368	register struct tm *lt;
369	register char *p;
370	time_t now;
371	int this_year;
372
373	if (!strcasecmp(timearg, "now")) {		/* now */
374		offset = 0;
375		return;
376	}
377
378	(void)time(&now);
379	if (*timearg == '+') {				/* +minutes */
380		if (!isdigit(*++timearg))
381			badtime();
382		offset = atoi(timearg) * 60;
383		shuttime = now + offset;
384		return;
385	}
386
387	/* handle hh:mm by getting rid of the colon */
388	for (p = timearg; *p; ++p)
389		if (!isascii(*p) || !isdigit(*p))
390			if (*p == ':' && strlen(p) == 3) {
391				p[0] = p[1];
392				p[1] = p[2];
393				p[2] = '\0';
394			}
395			else
396				badtime();
397
398	unsetenv("TZ");					/* OUR timezone */
399	lt = localtime(&now);				/* current time val */
400
401	switch(strlen(timearg)) {
402	case 10:
403		this_year = lt->tm_year;
404		lt->tm_year = ATOI2(timearg);
405		/*
406		 * check if the specified year is in the next century.
407		 * allow for one year of user error as many people will
408		 * enter n - 1 at the start of year n.
409		 */
410		if (lt->tm_year < (this_year % 100) - 1)
411			lt->tm_year += 100;
412		/* adjust for the year 2000 and beyond */
413		lt->tm_year += (this_year - (this_year % 100));
414		/* FALLTHROUGH */
415	case 8:
416		lt->tm_mon = ATOI2(timearg);
417		if (--lt->tm_mon < 0 || lt->tm_mon > 11)
418			badtime();
419		/* FALLTHROUGH */
420	case 6:
421		lt->tm_mday = ATOI2(timearg);
422		if (lt->tm_mday < 1 || lt->tm_mday > 31)
423			badtime();
424		/* FALLTHROUGH */
425	case 4:
426		lt->tm_hour = ATOI2(timearg);
427		if (lt->tm_hour < 0 || lt->tm_hour > 23)
428			badtime();
429		lt->tm_min = ATOI2(timearg);
430		if (lt->tm_min < 0 || lt->tm_min > 59)
431			badtime();
432		lt->tm_sec = 0;
433		if ((shuttime = mktime(lt)) == -1)
434			badtime();
435		if ((offset = shuttime - now) < 0)
436			errx(1, "that time is already past.");
437		break;
438	default:
439		badtime();
440	}
441}
442
443#define	NOMSG	"\n\nNO LOGINS: System going down at "
444void
445nolog()
446{
447	int logfd;
448	char *ct;
449
450	(void)unlink(_PATH_NOLOGIN);	/* in case linked to another file */
451	(void)signal(SIGINT, finish);
452	(void)signal(SIGHUP, finish);
453	(void)signal(SIGQUIT, finish);
454	(void)signal(SIGTERM, finish);
455	if ((logfd = open(_PATH_NOLOGIN, O_WRONLY|O_CREAT|O_TRUNC,
456	    0664)) >= 0) {
457		(void)write(logfd, NOMSG, sizeof(NOMSG) - 1);
458		ct = ctime(&shuttime);
459		(void)write(logfd, ct + 11, 5);
460		(void)write(logfd, "\n\n", 2);
461		(void)write(logfd, mbuf, strlen(mbuf));
462		(void)close(logfd);
463	}
464}
465
466void
467finish(signo)
468	int signo;
469{
470	(void)unlink(_PATH_NOLOGIN);
471	exit(0);
472}
473
474void
475badtime()
476{
477	errx(1, "bad time format.");
478}
479
480void
481usage()
482{
483	fprintf(stderr, "usage: shutdown [-hknr] shutdowntime [ message ]\n");
484	exit(1);
485}
486