xref: /freebsd/sbin/reboot/reboot.c (revision ba3c1f5972d7b90feb6e6da47905ff2757e0fe57)
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/types.h>
47 #include <sys/boottrace.h>
48 #include <sys/reboot.h>
49 #include <sys/sysctl.h>
50 #include <sys/time.h>
51 
52 #include <signal.h>
53 #include <err.h>
54 #include <errno.h>
55 #include <fcntl.h>
56 #include <pwd.h>
57 #include <syslog.h>
58 #include <stdio.h>
59 #include <stdlib.h>
60 #include <string.h>
61 #include <unistd.h>
62 #include <utmpx.h>
63 
64 static void usage(void) __dead2;
65 static u_int get_pageins(void);
66 
67 static int dohalt;
68 
69 int
70 main(int argc, char *argv[])
71 {
72 	struct utmpx utx;
73 	const struct passwd *pw;
74 	int ch, howto, i, fd, lflag, nflag, qflag, sverrno, Nflag;
75 	u_int pageins;
76 	const char *user, *kernel = NULL;
77 
78 	if (strstr(getprogname(), "halt") != NULL) {
79 		dohalt = 1;
80 		howto = RB_HALT;
81 	} else
82 		howto = 0;
83 	lflag = nflag = qflag = Nflag = 0;
84 	while ((ch = getopt(argc, argv, "cdk:lNnpqr")) != -1)
85 		switch(ch) {
86 		case 'c':
87 			howto |= RB_POWERCYCLE;
88 			break;
89 		case 'd':
90 			howto |= RB_DUMP;
91 			break;
92 		case 'k':
93 			kernel = optarg;
94 			break;
95 		case 'l':
96 			lflag = 1;
97 			break;
98 		case 'n':
99 			nflag = 1;
100 			howto |= RB_NOSYNC;
101 			break;
102 		case 'N':
103 			nflag = 1;
104 			Nflag = 1;
105 			break;
106 		case 'p':
107 			howto |= RB_POWEROFF;
108 			break;
109 		case 'q':
110 			qflag = 1;
111 			break;
112 		case 'r':
113 			howto |= RB_REROOT;
114 			break;
115 		case '?':
116 		default:
117 			usage();
118 		}
119 	argc -= optind;
120 	argv += optind;
121 	if (argc != 0)
122 		usage();
123 
124 	if ((howto & (RB_DUMP | RB_HALT)) == (RB_DUMP | RB_HALT))
125 		errx(1, "cannot dump (-d) when halting; must reboot instead");
126 	if (Nflag && (howto & RB_NOSYNC) != 0)
127 		errx(1, "-N cannot be used with -n");
128 	if ((howto & RB_POWEROFF) && (howto & RB_POWERCYCLE))
129 		errx(1, "-c and -p cannot be used together");
130 	if ((howto & RB_REROOT) != 0 && howto != RB_REROOT)
131 		errx(1, "-r cannot be used with -c, -d, -n, or -p");
132 	if (geteuid()) {
133 		errno = EPERM;
134 		err(1, NULL);
135 	}
136 
137 	if (qflag) {
138 		reboot(howto);
139 		err(1, NULL);
140 	}
141 
142 	if (kernel != NULL) {
143 		fd = open("/boot/nextboot.conf", O_WRONLY | O_CREAT | O_TRUNC,
144 		    0444);
145 		if (fd > -1) {
146 			(void)write(fd, "nextboot_enable=\"YES\"\n", 22);
147 			(void)write(fd, "kernel=\"", 8L);
148 			(void)write(fd, kernel, strlen(kernel));
149 			(void)write(fd, "\"\n", 2);
150 			close(fd);
151 		}
152 	}
153 
154 	/* Log the reboot. */
155 	if (!lflag)  {
156 		if ((user = getlogin()) == NULL)
157 			user = (pw = getpwuid(getuid())) ?
158 			    pw->pw_name : "???";
159 		if (dohalt) {
160 			openlog("halt", 0, LOG_AUTH | LOG_CONS);
161 			syslog(LOG_CRIT, "halted by %s", user);
162 		} else if (howto & RB_REROOT) {
163 			openlog("reroot", 0, LOG_AUTH | LOG_CONS);
164 			syslog(LOG_CRIT, "rerooted by %s", user);
165 		} else if (howto & RB_POWEROFF) {
166 			openlog("reboot", 0, LOG_AUTH | LOG_CONS);
167 			syslog(LOG_CRIT, "powered off by %s", user);
168 		} else if (howto & RB_POWERCYCLE) {
169 			openlog("reboot", 0, LOG_AUTH | LOG_CONS);
170 			syslog(LOG_CRIT, "power cycled by %s", user);
171 		} else {
172 			openlog("reboot", 0, LOG_AUTH | LOG_CONS);
173 			syslog(LOG_CRIT, "rebooted by %s", user);
174 		}
175 	}
176 	utx.ut_type = SHUTDOWN_TIME;
177 	gettimeofday(&utx.ut_tv, NULL);
178 	pututxline(&utx);
179 
180 	/*
181 	 * Do a sync early on, so disks start transfers while we're off
182 	 * killing processes.  Don't worry about writes done before the
183 	 * processes die, the reboot system call syncs the disks.
184 	 */
185 	if (!nflag)
186 		sync();
187 
188 	/*
189 	 * Ignore signals that we can get as a result of killing
190 	 * parents, group leaders, etc.
191 	 */
192 	(void)signal(SIGHUP,  SIG_IGN);
193 	(void)signal(SIGINT,  SIG_IGN);
194 	(void)signal(SIGQUIT, SIG_IGN);
195 	(void)signal(SIGTERM, SIG_IGN);
196 	(void)signal(SIGTSTP, SIG_IGN);
197 
198 	/*
199 	 * If we're running in a pipeline, we don't want to die
200 	 * after killing whatever we're writing to.
201 	 */
202 	(void)signal(SIGPIPE, SIG_IGN);
203 
204 	/*
205 	 * Only init(8) can perform rerooting.
206 	 */
207 	if (howto & RB_REROOT) {
208 		if (kill(1, SIGEMT) == -1)
209 			err(1, "SIGEMT init");
210 
211 		return (0);
212 	}
213 
214 	/* Just stop init -- if we fail, we'll restart it. */
215 	BOOTTRACE("SIGTSTP to init(8)...");
216 	if (kill(1, SIGTSTP) == -1)
217 		err(1, "SIGTSTP init");
218 
219 	/* Send a SIGTERM first, a chance to save the buffers. */
220 	BOOTTRACE("SIGTERM to all other processes...");
221 	if (kill(-1, SIGTERM) == -1 && errno != ESRCH)
222 		err(1, "SIGTERM processes");
223 
224 	/*
225 	 * After the processes receive the signal, start the rest of the
226 	 * buffers on their way.  Wait 5 seconds between the SIGTERM and
227 	 * the SIGKILL to give everybody a chance. If there is a lot of
228 	 * paging activity then wait longer, up to a maximum of approx
229 	 * 60 seconds.
230 	 */
231 	sleep(2);
232 	for (i = 0; i < 20; i++) {
233 		pageins = get_pageins();
234 		if (!nflag)
235 			sync();
236 		sleep(3);
237 		if (get_pageins() == pageins)
238 			break;
239 	}
240 
241 	for (i = 1;; ++i) {
242 		BOOTTRACE("SIGKILL to all other processes(%d)...", i);
243 		if (kill(-1, SIGKILL) == -1) {
244 			if (errno == ESRCH)
245 				break;
246 			goto restart;
247 		}
248 		if (i > 5) {
249 			(void)fprintf(stderr,
250 			    "WARNING: some process(es) wouldn't die\n");
251 			break;
252 		}
253 		(void)sleep(2 * i);
254 	}
255 
256 	reboot(howto);
257 	/* FALLTHROUGH */
258 
259 restart:
260 	BOOTTRACE("SIGHUP to init(8)...");
261 	sverrno = errno;
262 	errx(1, "%s%s", kill(1, SIGHUP) == -1 ? "(can't restart init): " : "",
263 	    strerror(sverrno));
264 	/* NOTREACHED */
265 }
266 
267 static void
268 usage(void)
269 {
270 
271 	(void)fprintf(stderr, dohalt ?
272 	    "usage: halt [-clNnpq] [-k kernel]\n" :
273 	    "usage: reboot [-cdlNnpqr] [-k kernel]\n");
274 	exit(1);
275 }
276 
277 static u_int
278 get_pageins(void)
279 {
280 	u_int pageins;
281 	size_t len;
282 
283 	len = sizeof(pageins);
284 	if (sysctlbyname("vm.stats.vm.v_swappgsin", &pageins, &len, NULL, 0)
285 	    != 0) {
286 		warnx("v_swappgsin");
287 		return (0);
288 	}
289 	return pageins;
290 }
291