1/*
2 * Copyright (c) 1980, 1986, 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
32static const char copyright[] =
33"@(#) Copyright (c) 1980, 1986, 1993\n\
34	The Regents of the University of California.  All rights reserved.\n";
35#endif /* not lint */
36
37#ifndef lint
38static char sccsid[] = "@(#)reboot.c	8.1 (Berkeley) 6/5/93";
39#endif /* not lint */
40#endif
41#include <sys/cdefs.h>
42__FBSDID("$FreeBSD: stable/10/sbin/reboot/reboot.c 332465 2018-04-13 03:47:41Z rgrimes $");
43
44#include <sys/reboot.h>
45#include <sys/time.h>
46#include <sys/types.h>
47#include <sys/sysctl.h>
48#include <signal.h>
49#include <err.h>
50#include <errno.h>
51#include <fcntl.h>
52#include <pwd.h>
53#include <syslog.h>
54#include <stdio.h>
55#include <stdlib.h>
56#include <string.h>
57#include <unistd.h>
58#include <utmpx.h>
59
60static void usage(void);
61static u_int get_pageins(void);
62
63static int dohalt;
64
65int
66main(int argc, char *argv[])
67{
68	struct utmpx utx;
69	const struct passwd *pw;
70	int ch, howto, i, fd, lflag, nflag, qflag, sverrno, Nflag;
71	u_int pageins;
72	const char *user, *kernel = NULL;
73
74	if (strcmp(getprogname(), "halt") == 0) {
75		dohalt = 1;
76		howto = RB_HALT;
77	} else
78		howto = 0;
79	lflag = nflag = qflag = Nflag = 0;
80	while ((ch = getopt(argc, argv, "dk:lNnpqr")) != -1)
81		switch(ch) {
82		case 'd':
83			howto |= RB_DUMP;
84			break;
85		case 'k':
86			kernel = optarg;
87			break;
88		case 'l':
89			lflag = 1;
90			break;
91		case 'n':
92			nflag = 1;
93			howto |= RB_NOSYNC;
94			break;
95		case 'N':
96			nflag = 1;
97			Nflag = 1;
98			break;
99		case 'p':
100			howto |= RB_POWEROFF;
101			break;
102		case 'q':
103			qflag = 1;
104			break;
105		case 'r':
106			howto |= RB_REROOT;
107			break;
108		case '?':
109		default:
110			usage();
111		}
112	argc -= optind;
113	argv += optind;
114	if (argc != 0)
115		usage();
116
117	if ((howto & (RB_DUMP | RB_HALT)) == (RB_DUMP | RB_HALT))
118		errx(1, "cannot dump (-d) when halting; must reboot instead");
119	if (Nflag && (howto & RB_NOSYNC) != 0)
120		errx(1, "-N cannot be used with -n");
121	if ((howto & RB_REROOT) != 0 && howto != RB_REROOT)
122		errx(1, "-r cannot be used with -d, -n, or -p");
123	if (geteuid()) {
124		errno = EPERM;
125		err(1, NULL);
126	}
127
128	if (qflag) {
129		reboot(howto);
130		err(1, NULL);
131	}
132
133	if (kernel != NULL) {
134		fd = open("/boot/nextboot.conf", O_WRONLY | O_CREAT | O_TRUNC,
135		    0444);
136		if (fd > -1) {
137			(void)write(fd, "nextboot_enable=\"YES\"\n", 22);
138			(void)write(fd, "kernel=\"", 8L);
139			(void)write(fd, kernel, strlen(kernel));
140			(void)write(fd, "\"\n", 2);
141			close(fd);
142		}
143	}
144
145	/* Log the reboot. */
146	if (!lflag)  {
147		if ((user = getlogin()) == NULL)
148			user = (pw = getpwuid(getuid())) ?
149			    pw->pw_name : "???";
150		if (dohalt) {
151			openlog("halt", 0, LOG_AUTH | LOG_CONS);
152			syslog(LOG_CRIT, "halted by %s", user);
153		} else if (howto & RB_REROOT) {
154			openlog("reroot", 0, LOG_AUTH | LOG_CONS);
155			syslog(LOG_CRIT, "rerooted by %s", user);
156		} else {
157			openlog("reboot", 0, LOG_AUTH | LOG_CONS);
158			syslog(LOG_CRIT, "rebooted by %s", user);
159		}
160	}
161	utx.ut_type = SHUTDOWN_TIME;
162	gettimeofday(&utx.ut_tv, NULL);
163	pututxline(&utx);
164
165	/*
166	 * Do a sync early on, so disks start transfers while we're off
167	 * killing processes.  Don't worry about writes done before the
168	 * processes die, the reboot system call syncs the disks.
169	 */
170	if (!nflag)
171		sync();
172
173	/*
174	 * Ignore signals that we can get as a result of killing
175	 * parents, group leaders, etc.
176	 */
177	(void)signal(SIGHUP,  SIG_IGN);
178	(void)signal(SIGINT,  SIG_IGN);
179	(void)signal(SIGQUIT, SIG_IGN);
180	(void)signal(SIGTERM, SIG_IGN);
181	(void)signal(SIGTSTP, SIG_IGN);
182
183	/*
184	 * If we're running in a pipeline, we don't want to die
185	 * after killing whatever we're writing to.
186	 */
187	(void)signal(SIGPIPE, SIG_IGN);
188
189	/*
190	 * Only init(8) can perform rerooting.
191	 */
192	if (howto & RB_REROOT) {
193		if (kill(1, SIGEMT) == -1)
194			err(1, "SIGEMT init");
195
196		return (0);
197	}
198
199	/* Just stop init -- if we fail, we'll restart it. */
200	if (kill(1, SIGTSTP) == -1)
201		err(1, "SIGTSTP init");
202
203	/* Send a SIGTERM first, a chance to save the buffers. */
204	if (kill(-1, SIGTERM) == -1 && errno != ESRCH)
205		err(1, "SIGTERM processes");
206
207	/*
208	 * After the processes receive the signal, start the rest of the
209	 * buffers on their way.  Wait 5 seconds between the SIGTERM and
210	 * the SIGKILL to give everybody a chance. If there is a lot of
211	 * paging activity then wait longer, up to a maximum of approx
212	 * 60 seconds.
213	 */
214	sleep(2);
215	for (i = 0; i < 20; i++) {
216		pageins = get_pageins();
217		if (!nflag)
218			sync();
219		sleep(3);
220		if (get_pageins() == pageins)
221			break;
222	}
223
224	for (i = 1;; ++i) {
225		if (kill(-1, SIGKILL) == -1) {
226			if (errno == ESRCH)
227				break;
228			goto restart;
229		}
230		if (i > 5) {
231			(void)fprintf(stderr,
232			    "WARNING: some process(es) wouldn't die\n");
233			break;
234		}
235		(void)sleep(2 * i);
236	}
237
238	reboot(howto);
239	/* FALLTHROUGH */
240
241restart:
242	sverrno = errno;
243	errx(1, "%s%s", kill(1, SIGHUP) == -1 ? "(can't restart init): " : "",
244	    strerror(sverrno));
245	/* NOTREACHED */
246}
247
248static void
249usage(void)
250{
251
252	(void)fprintf(stderr, dohalt ?
253	    "usage: halt [-lNnpq] [-k kernel]\n" :
254	    "usage: reboot [-dlNnpqr] [-k kernel]\n");
255	exit(1);
256}
257
258static u_int
259get_pageins(void)
260{
261	u_int pageins;
262	size_t len;
263
264	len = sizeof(pageins);
265	if (sysctlbyname("vm.stats.vm.v_swappgsin", &pageins, &len, NULL, 0)
266	    != 0) {
267		warnx("v_swappgsin");
268		return (0);
269	}
270	return pageins;
271}
272