xref: /freebsd/sbin/reboot/reboot.c (revision 63a938566d524836885917d95bd491aa4400b181)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1980, 1986, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #if 0
33 #ifndef lint
34 static const char copyright[] =
35 "@(#) Copyright (c) 1980, 1986, 1993\n\
36 	The Regents of the University of California.  All rights reserved.\n";
37 #endif /* not lint */
38 
39 #ifndef lint
40 static char sccsid[] = "@(#)reboot.c	8.1 (Berkeley) 6/5/93";
41 #endif /* not lint */
42 #endif
43 #include <sys/cdefs.h>
44 __FBSDID("$FreeBSD$");
45 
46 #include <sys/reboot.h>
47 #include <sys/time.h>
48 #include <sys/types.h>
49 #include <sys/sysctl.h>
50 #include <signal.h>
51 #include <err.h>
52 #include <errno.h>
53 #include <fcntl.h>
54 #include <pwd.h>
55 #include <syslog.h>
56 #include <stdio.h>
57 #include <stdlib.h>
58 #include <string.h>
59 #include <unistd.h>
60 #include <utmpx.h>
61 
62 static void usage(void);
63 static u_int get_pageins(void);
64 
65 static int dohalt;
66 
67 int
68 main(int argc, char *argv[])
69 {
70 	struct utmpx utx;
71 	const struct passwd *pw;
72 	int ch, howto, i, fd, lflag, nflag, qflag, sverrno, Nflag;
73 	u_int pageins;
74 	const char *user, *kernel = NULL;
75 
76 	if (strcmp(getprogname(), "halt") == 0) {
77 		dohalt = 1;
78 		howto = RB_HALT;
79 	} else
80 		howto = 0;
81 	lflag = nflag = qflag = Nflag = 0;
82 	while ((ch = getopt(argc, argv, "cdk:lNnpqr")) != -1)
83 		switch(ch) {
84 		case 'c':
85 			howto |= RB_POWERCYCLE;
86 			break;
87 		case 'd':
88 			howto |= RB_DUMP;
89 			break;
90 		case 'k':
91 			kernel = optarg;
92 			break;
93 		case 'l':
94 			lflag = 1;
95 			break;
96 		case 'n':
97 			nflag = 1;
98 			howto |= RB_NOSYNC;
99 			break;
100 		case 'N':
101 			nflag = 1;
102 			Nflag = 1;
103 			break;
104 		case 'p':
105 			howto |= RB_POWEROFF;
106 			break;
107 		case 'q':
108 			qflag = 1;
109 			break;
110 		case 'r':
111 			howto |= RB_REROOT;
112 			break;
113 		case '?':
114 		default:
115 			usage();
116 		}
117 	argc -= optind;
118 	argv += optind;
119 
120 	if ((howto & (RB_DUMP | RB_HALT)) == (RB_DUMP | RB_HALT))
121 		errx(1, "cannot dump (-d) when halting; must reboot instead");
122 	if (Nflag && (howto & RB_NOSYNC) != 0)
123 		errx(1, "-N cannot be used with -n");
124 	if ((howto & RB_POWEROFF) && (howto & RB_POWERCYCLE))
125 		errx(1, "-c and -p cannot be used together");
126 	if ((howto & RB_REROOT) != 0 && howto != RB_REROOT)
127 		errx(1, "-r cannot be used with -c, -d, -n, or -p");
128 	if (geteuid()) {
129 		errno = EPERM;
130 		err(1, NULL);
131 	}
132 
133 	if (qflag) {
134 		reboot(howto);
135 		err(1, NULL);
136 	}
137 
138 	if (kernel != NULL) {
139 		fd = open("/boot/nextboot.conf", O_WRONLY | O_CREAT | O_TRUNC,
140 		    0444);
141 		if (fd > -1) {
142 			(void)write(fd, "nextboot_enable=\"YES\"\n", 22);
143 			(void)write(fd, "kernel=\"", 8L);
144 			(void)write(fd, kernel, strlen(kernel));
145 			(void)write(fd, "\"\n", 2);
146 			close(fd);
147 		}
148 	}
149 
150 	/* Log the reboot. */
151 	if (!lflag)  {
152 		if ((user = getlogin()) == NULL)
153 			user = (pw = getpwuid(getuid())) ?
154 			    pw->pw_name : "???";
155 		if (dohalt) {
156 			openlog("halt", 0, LOG_AUTH | LOG_CONS);
157 			syslog(LOG_CRIT, "halted by %s", user);
158 		} else if (howto & RB_REROOT) {
159 			openlog("reroot", 0, LOG_AUTH | LOG_CONS);
160 			syslog(LOG_CRIT, "rerooted by %s", user);
161 		} else if (howto & RB_POWEROFF) {
162 			openlog("reboot", 0, LOG_AUTH | LOG_CONS);
163 			syslog(LOG_CRIT, "powered off by %s", user);
164 		} else if (howto & RB_POWERCYCLE) {
165 			openlog("reboot", 0, LOG_AUTH | LOG_CONS);
166 			syslog(LOG_CRIT, "power cycled by %s", user);
167 		} else {
168 			openlog("reboot", 0, LOG_AUTH | LOG_CONS);
169 			syslog(LOG_CRIT, "rebooted by %s", user);
170 		}
171 	}
172 	utx.ut_type = SHUTDOWN_TIME;
173 	gettimeofday(&utx.ut_tv, NULL);
174 	pututxline(&utx);
175 
176 	/*
177 	 * Do a sync early on, so disks start transfers while we're off
178 	 * killing processes.  Don't worry about writes done before the
179 	 * processes die, the reboot system call syncs the disks.
180 	 */
181 	if (!nflag)
182 		sync();
183 
184 	/*
185 	 * Ignore signals that we can get as a result of killing
186 	 * parents, group leaders, etc.
187 	 */
188 	(void)signal(SIGHUP,  SIG_IGN);
189 	(void)signal(SIGINT,  SIG_IGN);
190 	(void)signal(SIGQUIT, SIG_IGN);
191 	(void)signal(SIGTERM, SIG_IGN);
192 	(void)signal(SIGTSTP, SIG_IGN);
193 
194 	/*
195 	 * If we're running in a pipeline, we don't want to die
196 	 * after killing whatever we're writing to.
197 	 */
198 	(void)signal(SIGPIPE, SIG_IGN);
199 
200 	/*
201 	 * Only init(8) can perform rerooting.
202 	 */
203 	if (howto & RB_REROOT) {
204 		if (kill(1, SIGEMT) == -1)
205 			err(1, "SIGEMT init");
206 
207 		return (0);
208 	}
209 
210 	/* Just stop init -- if we fail, we'll restart it. */
211 	if (kill(1, SIGTSTP) == -1)
212 		err(1, "SIGTSTP init");
213 
214 	/* Send a SIGTERM first, a chance to save the buffers. */
215 	if (kill(-1, SIGTERM) == -1 && errno != ESRCH)
216 		err(1, "SIGTERM processes");
217 
218 	/*
219 	 * After the processes receive the signal, start the rest of the
220 	 * buffers on their way.  Wait 5 seconds between the SIGTERM and
221 	 * the SIGKILL to give everybody a chance. If there is a lot of
222 	 * paging activity then wait longer, up to a maximum of approx
223 	 * 60 seconds.
224 	 */
225 	sleep(2);
226 	for (i = 0; i < 20; i++) {
227 		pageins = get_pageins();
228 		if (!nflag)
229 			sync();
230 		sleep(3);
231 		if (get_pageins() == pageins)
232 			break;
233 	}
234 
235 	for (i = 1;; ++i) {
236 		if (kill(-1, SIGKILL) == -1) {
237 			if (errno == ESRCH)
238 				break;
239 			goto restart;
240 		}
241 		if (i > 5) {
242 			(void)fprintf(stderr,
243 			    "WARNING: some process(es) wouldn't die\n");
244 			break;
245 		}
246 		(void)sleep(2 * i);
247 	}
248 
249 	reboot(howto);
250 	/* FALLTHROUGH */
251 
252 restart:
253 	sverrno = errno;
254 	errx(1, "%s%s", kill(1, SIGHUP) == -1 ? "(can't restart init): " : "",
255 	    strerror(sverrno));
256 	/* NOTREACHED */
257 }
258 
259 static void
260 usage(void)
261 {
262 
263 	(void)fprintf(stderr, dohalt ?
264 	    "usage: halt [-clNnpq] [-k kernel]\n" :
265 	    "usage: reboot [-cdlNnpqr] [-k kernel]\n");
266 	exit(1);
267 }
268 
269 static u_int
270 get_pageins(void)
271 {
272 	u_int pageins;
273 	size_t len;
274 
275 	len = sizeof(pageins);
276 	if (sysctlbyname("vm.stats.vm.v_swappgsin", &pageins, &len, NULL, 0)
277 	    != 0) {
278 		warnx("v_swappgsin");
279 		return (0);
280 	}
281 	return pageins;
282 }
283