shutdown.c revision 38036 
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
35static 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
42static char sccsid[] = "@(#)shutdown.c	8.2 (Berkeley) 2/16/94";
43#endif
44static const char rcsid[] =
45	"$Id$";
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
75struct 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
95static time_t offset, shuttime;
96static int dohalt, doreboot, killflg, mbuflen;
97static char *nosync, *whom, mbuf[BUFSIZ];
98
99void badtime __P((void));
100void die_you_gravy_sucking_pig_dog __P((void));
101void finish __P((int));
102void getoffset __P((char *));
103void loop __P((void));
104void nolog __P((void));
105void timeout __P((int));
106void timewarn __P((int));
107void usage __P((void));
108
109int
110main(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, "-hknr")) != -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 'r':
139			doreboot = 1;
140			break;
141		case '?':
142		default:
143			usage();
144		}
145	argc -= optind;
146	argv += optind;
147
148	if (argc < 1)
149		usage();
150
151	if (doreboot && dohalt) {
152		warnx("incompatible switches -h and -r");
153		usage();
154	}
155	getoffset(*argv++);
156
157	if (*argv) {
158		for (p = mbuf, len = sizeof(mbuf); *argv; ++argv) {
159			arglen = strlen(*argv);
160			if ((len -= arglen) <= 2)
161				break;
162			if (p != mbuf)
163				*p++ = ' ';
164			bcopy(*argv, p, arglen);
165			p += arglen;
166		}
167		*p = '\n';
168		*++p = '\0';
169	}
170
171	if (readstdin) {
172		p = mbuf;
173		endp = mbuf + sizeof(mbuf) - 2;
174		for (;;) {
175			if (!fgets(p, endp - p + 1, stdin))
176				break;
177			for (; *p &&  p < endp; ++p);
178			if (p == endp) {
179				*p = '\n';
180				*++p = '\0';
181				break;
182			}
183		}
184	}
185	mbuflen = strlen(mbuf);
186
187	if (offset)
188		(void)printf("Shutdown at %.24s.\n", ctime(&shuttime));
189	else
190		(void)printf("Shutdown NOW!\n");
191
192	if (!(whom = getlogin()))
193		whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???";
194
195#ifdef DEBUG
196	(void)putc('\n', stdout);
197#else
198	(void)setpriority(PRIO_PROCESS, 0, PRIO_MIN);
199	{
200		int forkpid;
201
202		forkpid = fork();
203		if (forkpid == -1)
204			err(1, "fork");
205		if (forkpid)
206			errx(0, "[pid %d]", forkpid);
207	}
208	setsid();
209#endif
210	openlog("shutdown", LOG_CONS, LOG_AUTH);
211	loop();
212	return(0);
213}
214
215void
216loop()
217{
218	struct interval *tp;
219	u_int sltime;
220	int logged;
221
222	if (offset <= NOLOG_TIME) {
223		logged = 1;
224		nolog();
225	}
226	else
227		logged = 0;
228	tp = tlist;
229	if (tp->timeleft < offset)
230		(void)sleep((u_int)(offset - tp->timeleft));
231	else {
232		while (offset < tp->timeleft)
233			++tp;
234		/*
235		 * Warn now, if going to sleep more than a fifth of
236		 * the next wait time.
237		 */
238		if ((sltime = offset - tp->timeleft)) {
239			if (sltime > tp->timetowait / 5)
240				timewarn(offset);
241			(void)sleep(sltime);
242		}
243	}
244	for (;; ++tp) {
245		timewarn(tp->timeleft);
246		if (!logged && tp->timeleft <= NOLOG_TIME) {
247			logged = 1;
248			nolog();
249		}
250		(void)sleep((u_int)tp->timetowait);
251		if (!tp->timeleft)
252			break;
253	}
254	die_you_gravy_sucking_pig_dog();
255}
256
257static jmp_buf alarmbuf;
258
259static char *restricted_environ[] = {
260	"PATH=" _PATH_STDPATH,
261	NULL
262};
263
264void
265timewarn(timeleft)
266	int timeleft;
267{
268	static int first;
269	static char hostname[MAXHOSTNAMELEN + 1];
270	FILE *pf;
271	char wcmd[MAXPATHLEN + 4];
272	extern char **environ;
273
274	if (!first++)
275		(void)gethostname(hostname, sizeof(hostname));
276
277	/* undoc -n option to wall suppresses normal wall banner */
278	(void)snprintf(wcmd, sizeof(wcmd), "%s -n", _PATH_WALL);
279	environ = restricted_environ;
280	if (!(pf = popen(wcmd, "w"))) {
281		syslog(LOG_ERR, "shutdown: can't find %s: %m", _PATH_WALL);
282		return;
283	}
284
285	(void)fprintf(pf,
286	    "\007*** %sSystem shutdown message from %s@%s ***\007\n",
287	    timeleft ? "": "FINAL ", whom, hostname);
288
289	if (timeleft > 10*60)
290		(void)fprintf(pf, "System going down at %5.5s\n\n",
291		    ctime(&shuttime) + 11);
292	else if (timeleft > 59)
293		(void)fprintf(pf, "System going down in %d minute%s\n\n",
294		    timeleft / 60, (timeleft > 60) ? "s" : "");
295	else if (timeleft)
296		(void)fprintf(pf, "System going down in 30 seconds\n\n");
297	else
298		(void)fprintf(pf, "System going down IMMEDIATELY\n\n");
299
300	if (mbuflen)
301		(void)fwrite(mbuf, sizeof(*mbuf), mbuflen, pf);
302
303	/*
304	 * play some games, just in case wall doesn't come back
305	 * probably unnecessary, given that wall is careful.
306	 */
307	if (!setjmp(alarmbuf)) {
308		(void)signal(SIGALRM, timeout);
309		(void)alarm((u_int)30);
310		(void)pclose(pf);
311		(void)alarm((u_int)0);
312		(void)signal(SIGALRM, SIG_DFL);
313	}
314}
315
316void
317timeout(signo)
318	int signo;
319{
320	longjmp(alarmbuf, 1);
321}
322
323void
324die_you_gravy_sucking_pig_dog()
325{
326	char *empty_environ[] = { NULL };
327
328	syslog(LOG_NOTICE, "%s by %s: %s",
329	    doreboot ? "reboot" : dohalt ? "halt" : "shutdown", whom, mbuf);
330	(void)sleep(2);
331
332	(void)printf("\r\nSystem shutdown time has arrived\007\007\r\n");
333	if (killflg) {
334		(void)printf("\rbut you'll have to do it yourself\r\n");
335		exit(0);
336	}
337#ifdef DEBUG
338	if (doreboot)
339		(void)printf("reboot");
340	else if (dohalt)
341		(void)printf("halt");
342	if (nosync)
343		(void)printf(" no sync");
344	(void)printf("\nkill -HUP 1\n");
345#else
346	if (doreboot) {
347		execle(_PATH_REBOOT, "reboot", "-l", nosync,
348			   (char *)NULL, empty_environ);
349		syslog(LOG_ERR, "shutdown: can't exec %s: %m.", _PATH_REBOOT);
350		warn(_PATH_REBOOT);
351	}
352	else if (dohalt) {
353		execle(_PATH_HALT, "halt", "-l", nosync,
354			   (char *)NULL, empty_environ);
355		syslog(LOG_ERR, "shutdown: can't exec %s: %m.", _PATH_HALT);
356		warn(_PATH_HALT);
357	}
358	(void)kill(1, SIGTERM);		/* to single user */
359#endif
360	finish(0);
361}
362
363#define	ATOI2(p)	(p[0] - '0') * 10 + (p[1] - '0'); p += 2;
364
365void
366getoffset(timearg)
367	register char *timearg;
368{
369	register struct tm *lt;
370	register char *p;
371	time_t now;
372	int this_year;
373
374	if (!strcasecmp(timearg, "now")) {		/* now */
375		offset = 0;
376		return;
377	}
378
379	(void)time(&now);
380	if (*timearg == '+') {				/* +minutes */
381		if (!isdigit(*++timearg))
382			badtime();
383		offset = atoi(timearg) * 60;
384		shuttime = now + offset;
385		return;
386	}
387
388	/* handle hh:mm by getting rid of the colon */
389	for (p = timearg; *p; ++p)
390		if (!isascii(*p) || !isdigit(*p))
391			if (*p == ':' && strlen(p) == 3) {
392				p[0] = p[1];
393				p[1] = p[2];
394				p[2] = '\0';
395			}
396			else
397				badtime();
398
399	unsetenv("TZ");					/* OUR timezone */
400	lt = localtime(&now);				/* current time val */
401
402	switch(strlen(timearg)) {
403	case 10:
404		this_year = lt->tm_year;
405		lt->tm_year = ATOI2(timearg);
406		/*
407		 * check if the specified year is in the next century.
408		 * allow for one year of user error as many people will
409		 * enter n - 1 at the start of year n.
410		 */
411		if (lt->tm_year < (this_year % 100) - 1)
412			lt->tm_year += 100;
413		/* adjust for the year 2000 and beyond */
414		lt->tm_year += (this_year - (this_year % 100));
415		/* FALLTHROUGH */
416	case 8:
417		lt->tm_mon = ATOI2(timearg);
418		if (--lt->tm_mon < 0 || lt->tm_mon > 11)
419			badtime();
420		/* FALLTHROUGH */
421	case 6:
422		lt->tm_mday = ATOI2(timearg);
423		if (lt->tm_mday < 1 || lt->tm_mday > 31)
424			badtime();
425		/* FALLTHROUGH */
426	case 4:
427		lt->tm_hour = ATOI2(timearg);
428		if (lt->tm_hour < 0 || lt->tm_hour > 23)
429			badtime();
430		lt->tm_min = ATOI2(timearg);
431		if (lt->tm_min < 0 || lt->tm_min > 59)
432			badtime();
433		lt->tm_sec = 0;
434		if ((shuttime = mktime(lt)) == -1)
435			badtime();
436		if ((offset = shuttime - now) < 0)
437			errx(1, "that time is already past.");
438		break;
439	default:
440		badtime();
441	}
442}
443
444#define	NOMSG	"\n\nNO LOGINS: System going down at "
445void
446nolog()
447{
448	int logfd;
449	char *ct;
450
451	(void)unlink(_PATH_NOLOGIN);	/* in case linked to another file */
452	(void)signal(SIGINT, finish);
453	(void)signal(SIGHUP, finish);
454	(void)signal(SIGQUIT, finish);
455	(void)signal(SIGTERM, finish);
456	if ((logfd = open(_PATH_NOLOGIN, O_WRONLY|O_CREAT|O_TRUNC,
457	    0664)) >= 0) {
458		(void)write(logfd, NOMSG, sizeof(NOMSG) - 1);
459		ct = ctime(&shuttime);
460		(void)write(logfd, ct + 11, 5);
461		(void)write(logfd, "\n\n", 2);
462		(void)write(logfd, mbuf, strlen(mbuf));
463		(void)close(logfd);
464	}
465}
466
467void
468finish(signo)
469	int signo;
470{
471	(void)unlink(_PATH_NOLOGIN);
472	exit(0);
473}
474
475void
476badtime()
477{
478	errx(1, "bad time format");
479}
480
481void
482usage()
483{
484	fprintf(stderr, "usage: shutdown [-hknr] shutdowntime [ message ]\n");
485	exit(1);
486}
487