xref: /NextBSD/sbin/launchd/init/init.c (revision 33da5adc555b3bc29986eeadca03829e4ad06b1e)
1 /*
2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
3  *
4  * @APPLE_APACHE_LICENSE_HEADER_START@
5  *
6  * Licensed under the Apache License, Version 2.0 (the "License");
7  * you may not use this file except in compliance with the License.
8  * You may obtain a copy of the License at
9  *
10  *     http://www.apache.org/licenses/LICENSE-2.0
11  *
12  * Unless required by applicable law or agreed to in writing, software
13  * distributed under the License is distributed on an "AS IS" BASIS,
14  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15  * See the License for the specific language governing permissions and
16  * limitations under the License.
17  *
18  * @APPLE_APACHE_LICENSE_HEADER_END@
19  */
20 /*-
21  * Copyright (c) 1991, 1993
22  *      The Regents of the University of California.  All rights reserved.
23  *
24  * This code is derived from software contributed to Berkeley by
25  * Donn Seeley at Berkeley Software Design, Inc.
26  *
27  * Redistribution and use in source and binary forms, with or without
28  * modification, are permitted provided that the following conditions
29  * are met:
30  * 1. Redistributions of source code must retain the above copyright
31  *    notice, this list of conditions and the following disclaimer.
32  * 2. Redistributions in binary form must reproduce the above copyright
33  *    notice, this list of conditions and the following disclaimer in the
34  *    documentation and/or other materials provided with the distribution.
35  * 3. All advertising materials mentioning features or use of this software
36  *    must display the following acknowledgement:
37  *      This product includes software developed by the University of
38  *      California, Berkeley and its contributors.
39  * 4. Neither the name of the University nor the names of its contributors
40  *    may be used to endorse or promote products derived from this software
41  *    without specific prior written permission.
42  *
43  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
44  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
45  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
46  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
47  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
48  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
49  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
50  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
51  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
52  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
53  * SUCH DAMAGE.
54  */
55 
56 #if 0
57 #include <Security/Authorization.h>
58 #include <Security/AuthorizationTags.h>
59 #include <Security/AuthSession.h>
60 #endif
61 
62 #include <sys/types.h>
63 #include <sys/event.h>
64 #include <sys/queue.h>
65 #include <sys/param.h>
66 #include <sys/mount.h>
67 #include <sys/sysctl.h>
68 #include <sys/wait.h>
69 #include <sys/time.h>
70 #include <sys/resource.h>
71 
72 #include <errno.h>
73 #include <fcntl.h>
74 #include <signal.h>
75 #include <stdio.h>
76 #include <stdlib.h>
77 #include <stdarg.h>
78 #include <stdbool.h>
79 #include <string.h>
80 #include <syslog.h>
81 #include <time.h>
82 #include <ttyent.h>
83 #include <unistd.h>
84 #include <paths.h>
85 #include <util.h>
86 #include <libgen.h>
87 #include <paths.h>
88 #include <termios.h>
89 
90 #include "launchd.h"
91 
92 #define _PATH_RUNCOM            "/etc/rc"
93 
94 /*
95  * Sleep times; used to prevent thrashing.
96  */
97 #define	GETTY_SPACING		 5	/* N secs minimum getty spacing */
98 #define	GETTY_SLEEP		30	/* sleep N secs after spacing problem */
99 #define	STALL_TIMEOUT		30	/* wait N secs after warning */
100 #define	DEATH_WATCH		10	/* wait N secs for procs to die */
101 #define FAILED_HW_PASS		 5	/* wait N secs before croaking user */
102 
103 static void stall(const char *, ...);
104 
105 static void single_user_callback(void *, struct kevent *);
106 static kq_callback kqsingle_user_callback = single_user_callback;
107 static void runcom_callback(void *, struct kevent *);
108 static kq_callback kqruncom_callback = runcom_callback;
109 
110 static void single_user(void);
111 static void runcom(void);
112 
113 static bool runcom_safe = false;
114 static bool runcom_netboot = false;
115 static bool single_user_mode = false;
116 static bool run_runcom = true;
117 static pid_t single_user_pid = 0;
118 static pid_t runcom_pid = 0;
119 
120 static void setctty(const char *, int);
121 
122 // gvdl@next.com 14 Aug 1995
123 //   - from ~apps/loginwindow_proj/loginwindow/common.h
124 #define REALLY_EXIT_TO_CONSOLE                  229
125 
126 // From old init.c
127 // These flags are used in the se_flags field of the init_session structure
128 #define	SE_SHUTDOWN	0x1		/* session won't be restarted */
129 
130 // The flags below control what sort of getty is launched.
131 #define SE_GETTY_LAUNCH	0x30	/* What type of getty to launch */
132 #define SE_COMMON	0x00	/* Usual command that is run - getty */
133 #define SE_ONERROR	0x10	/* Command to run if error condition occurs.
134 				 * This will almost always be the windowserver
135 				 * and loginwindow.  This is so if the w.s.
136 				 * ever dies, that the naive user (stan)
137 				 * doesn't ever see the console window. */
138 #define SE_ONOPTION 	0x20	/* Command to run when loginwindow exits with
139 				 * special error code (229).  This signifies
140 				 * that the user typed "console" at l.w. and
141 				 * l.w. wants to exit and have init run getty
142 				 * which will then put up a console window. */
143 
144 typedef struct _se_command {
145 	char	*path;		/* what to run on that port */
146 	char	**argv;		/* pre-parsed argument array */
147 } se_cmd_t;
148 
149 typedef struct init_session {
150 	kq_callback se_callback;	/* run loop callback */
151 	int	se_index;		/* index of entry in ttys file */
152 	pid_t	se_process;		/* controlling process */
153 	time_t	se_started;		/* used to avoid thrashing */
154 	int	se_flags;		/* status of session */
155 	char	*se_device;		/* filename of port */
156 	se_cmd_t se_getty;		/* what to run on that port */
157 	se_cmd_t se_onerror;		/* See SE_ONERROR above */
158 	se_cmd_t se_onoption;		/* See SE_ONOPTION above */
159 	TAILQ_ENTRY(init_session) tqe;
160 } *session_t;
161 
162 static TAILQ_HEAD(sessionshead, init_session) sessions = TAILQ_HEAD_INITIALIZER(sessions);
163 
164 static void session_new(int, struct ttyent *);
165 static void session_free(session_t);
166 static void session_launch(session_t);
167 static void session_reap(session_t);
168 static void session_callback(void *, struct kevent *);
169 
170 static char **construct_argv(char *);
171 static void setsecuritylevel(int);
172 static int getsecuritylevel(void);
173 static int setupargv(session_t, struct ttyent *);
174 static bool should_fsck(void);
175 
176 void
init_boot(bool sflag __unused)177 init_boot(bool sflag __unused)
178 {
179 #if 0
180 	int nbmib[2] = { CTL_KERN, KERN_NETBOOT };
181 	int sbmib[2] = { CTL_KERN, KERN_SAFEBOOT };
182 	uint32_t v = 0;
183 	size_t vsz = sizeof(v);
184 
185 	if (sflag) {
186 		single_user_mode = true;
187 		run_runcom = false;
188 	}
189 
190 	if (launchd_assumes(sysctl(nbmib, 2, &v, &vsz, NULL, 0) != -1)) {
191 		if (v != 0)
192 			runcom_netboot = true;
193 	}
194 	if (launchd_assumes(sysctl(sbmib, 2, &v, &vsz, NULL, 0) != -1)) {
195 		if (v != 0)
196 			runcom_safe = true;
197 	}
198 #endif
199 }
200 
201 void
init_pre_kevent(bool sflag)202 init_pre_kevent(bool sflag)
203 {
204 	session_t s;
205 
206 	if (sflag) {
207 		single_user_mode = 1;
208 		run_runcom = 0;
209 	}
210 	syslog(LOG_EMERG, "starting init_pre_kevent() single_user_pid=%d runcom_pid=%d\n",
211 		   single_user_pid, runcom_pid);
212 	syslog(LOG_EMERG, "... single_user_mode=%d run_runcom=%d\n", single_user_mode, run_runcom);
213 	if (single_user_pid || runcom_pid) {
214 		syslog(LOG_ERR, "skipping()\n");
215 		return;
216 	}
217 	if (single_user_mode) {
218 		syslog(LOG_ERR, "single_user()\n");
219 		return single_user();
220 	}
221 	if (run_runcom) {
222 		syslog(LOG_EMERG, "runcom()\n");
223 		return runcom();
224 	}
225 	/*
226 	 * If the administrator has not set the security level to -1
227 	 * to indicate that the kernel should not run multiuser in secure
228 	 * mode, and the run script has not set a higher level of security
229 	 * than level 1, then put the kernel into secure mode.
230 	 */
231 	if (getsecuritylevel() == 0) {
232 		syslog(LOG_ERR, "setsecuritylevel()");
233 		setsecuritylevel(1);
234 	}
235 	TAILQ_FOREACH(s, &sessions, tqe) {
236 		if (s->se_process == 0) {
237 			syslog(LOG_ERR, "session_launch()");
238 			session_launch(s);
239 		}
240 	}
241 	syslog(LOG_ERR, "done init_pre_kevent()\n");
242 }
243 
244 static void
stall(const char * message,...)245 stall(const char *message, ...)
246 {
247 	va_list ap;
248 	va_start(ap, message);
249 
250 	vsyslog(LOG_ERR, message, ap);
251 	va_end(ap);
252 	sleep(STALL_TIMEOUT);
253 }
254 
255 static int
getsecuritylevel(void)256 getsecuritylevel(void)
257 {
258 	int name[2], curlevel;
259 	size_t len;
260 
261 	name[0] = CTL_KERN;
262 	name[1] = KERN_SECURELVL;
263 	len = sizeof (curlevel);
264 	if (sysctl(name, 2, &curlevel, &len, NULL, 0) == -1) {
265 		syslog(LOG_ALERT, "cannot get kernel security level: %m");
266 		return -1;
267 	}
268 	return curlevel;
269 }
270 
271 static void
setsecuritylevel(int newlevel)272 setsecuritylevel(int newlevel)
273 {
274 	int name[2], curlevel;
275 
276 	curlevel = getsecuritylevel();
277 	if (newlevel == curlevel)
278 		return;
279 	name[0] = CTL_KERN;
280 	name[1] = KERN_SECURELVL;
281 	if (sysctl(name, 2, NULL, NULL, &newlevel, sizeof newlevel) == -1) {
282 		syslog(LOG_ALERT, "cannot change kernel security level from %d to %d: %m",
283 				curlevel, newlevel);
284 		return;
285 	}
286 	syslog(LOG_INFO, "kernel security level changed from %d to %d",
287 	    curlevel, newlevel);
288 }
289 
290 /*
291  * Start a session and allocate a controlling terminal.
292  * Only called by children of init after forking.
293  */
294 static void
setctty(const char * name,int flags)295 setctty(const char *name, int flags)
296 {
297 	int fd;
298 
299 	revoke(name);
300 	if ((fd = open(name, flags | O_RDWR)) == -1) {
301 		stall("can't open %s: %m", name);
302 		launchd_exit(EXIT_FAILURE);
303 	}
304 	if (login_tty(fd) == -1) {
305 		stall("can't get %s for controlling terminal: %m", name);
306 		launchd_exit(EXIT_FAILURE);
307 	}
308 }
309 
310 static void
single_user(void)311 single_user(void)
312 {
313 	bool runcom_fsck = should_fsck();
314 	const char *argv[2];
315 
316 	if (getsecuritylevel() > 0)
317 		setsecuritylevel(0);
318 
319 	if ((single_user_pid = launchd_fork()) == -1) {
320 		syslog(LOG_ERR, "can't fork single-user shell, trying again: %m");
321 		return;
322 	} else if (single_user_pid == 0) {
323 #if 0
324 		setctty(_PATH_CONSOLE, O_POPUP);
325 #endif
326                 setenv("TERM", "vt100", 1);
327 		setenv("SafeBoot", runcom_safe ? "-x" : "", 1);
328 		setenv("VerboseFlag", "-v", 1); /* single user mode implies verbose mode */
329 		setenv("FsckSlash", runcom_fsck ? "-F" : "", 1);
330 		setenv("NetBoot", runcom_netboot ? "-N" : "", 1);
331 
332 		if (runcom_fsck) {
333 			fprintf(stdout, "Singleuser boot -- fsck not done\n");
334 			fprintf(stdout, "Root device is mounted read-only\n\n");
335 			fprintf(stdout, "If you want to make modifications to files:\n");
336 			fprintf(stdout, "\t/sbin/fsck -fy\n\t/sbin/mount -uw /\n\n");
337 			fprintf(stdout, "If you wish to boot the system:\n");
338 			fprintf(stdout, "\texit\n\n");
339 			fflush(stdout);
340 		}
341 
342 		argv[0] = "-sh";
343 		argv[1] = NULL;
344 		execv(_PATH_BSHELL, __DECONST(char *const *, argv));
345 		syslog(LOG_ERR, "can't exec %s for single user: %m", _PATH_BSHELL);
346 		sleep(STALL_TIMEOUT);
347 		launchd_exit(EXIT_FAILURE);
348 	} else {
349 		if (kevent_mod(single_user_pid, EVFILT_PROC, EV_ADD,
350 					NOTE_EXIT, 0, &kqsingle_user_callback) == -1)
351 			single_user_callback(NULL, NULL);
352 	}
353 }
354 
355 static void
single_user_callback(void * obj,struct kevent * kev)356 single_user_callback(void *obj __attribute__((unused)), struct kevent *kev __attribute__((unused)))
357 {
358 	int status;
359 
360 	if (!launchd_assumes(waitpid(single_user_pid, &status, 0) == single_user_pid))
361 		return;
362 
363 	if (WIFEXITED(status) && WEXITSTATUS(status) == EXIT_SUCCESS) {
364 		syslog(LOG_INFO, "single user shell terminated, restarting");
365 		run_runcom = true;
366 		single_user_mode = false;
367 	} else {
368 		syslog(LOG_INFO, "single user shell terminated.");
369 		run_runcom = false;
370 		if (WTERMSIG(status) != SIGKILL)
371 			single_user_mode = true;
372 	}
373 
374 	single_user_pid = 0;
375 }
376 
377 static struct timeval runcom_start_tv = { 0, 0 };
378 /*
379  * Run the system startup script.
380  */
381 static void
runcom(void)382 runcom(void)
383 {
384 	bool runcom_fsck = should_fsck();
385 	char *argv[4];
386 	struct termios term;
387 	int vdisable;
388 
389 	gettimeofday(&runcom_start_tv, NULL);
390 	syslog(LOG_ERR, "launchd_fork()\n");
391 	if ((runcom_pid = launchd_fork()) == -1) {
392 		syslog(LOG_ERR, "can't fork for %s on %s: %m", _PATH_BSHELL, _PATH_RUNCOM);
393 		sleep(STALL_TIMEOUT);
394 		runcom_pid = 0;
395 		single_user_mode = true;
396 		return;
397 	} else if (runcom_pid > 0) {
398 		run_runcom = false;
399 		if (kevent_mod(runcom_pid, EVFILT_PROC, EV_ADD,
400 					   NOTE_EXIT, 0, &kqruncom_callback) == -1) {
401 			syslog(LOG_ERR, "runcom_callback() ... ");
402 			runcom_callback(NULL, NULL);
403 			syslog(LOG_ERR, "done\n");
404 		}
405 		return;
406 	}
407 	syslog(LOG_ERR, "setctty()\n");
408 	setctty(_PATH_CONSOLE, 0);
409 
410 	syslog(LOG_ERR, "fpathconf()\n");
411 	sleep(1);
412 	if ((vdisable = fpathconf(STDIN_FILENO, _PC_VDISABLE)) == -1) {
413 		syslog(LOG_ERR, "fpathconf(\"%s\") %m", _PATH_CONSOLE);
414 	} else if (tcgetattr(STDIN_FILENO, &term) == -1) {
415 		syslog(LOG_ERR, "tcgetattr(\"%s\") %m", _PATH_CONSOLE);
416 	} else {
417 		term.c_cc[VINTR] = vdisable;
418 		term.c_cc[VKILL] = vdisable;
419 		term.c_cc[VQUIT] = vdisable;
420 		term.c_cc[VSUSP] = vdisable;
421 		term.c_cc[VSTART] = vdisable;
422 		term.c_cc[VSTOP] = vdisable;
423 		term.c_cc[VDSUSP] = vdisable;
424 		sleep(1);
425 		syslog(LOG_ERR, "tcsetattr(STDIN_FILENO) ...");
426 		if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &term) == -1)
427 			syslog(LOG_WARNING, "tcsetattr(\"%s\") %m", _PATH_CONSOLE);
428 		syslog(LOG_ERR, "done\n");
429 	}
430 	sleep(1);
431 	syslog(LOG_ERR, "setenv\n");
432 	setenv("SafeBoot", runcom_safe ? "-x" : "", 1);
433 	setenv("FsckSlash", runcom_fsck ? "-F" : "", 1);
434 	setenv("NetBoot", runcom_netboot ? "-N" : "", 1);
435 	syslog(LOG_ERR, "execv\n");
436 	{
437 		char _sh[] = "sh";
438 		int err;
439 
440 		argv[0] = _sh;
441 		argv[1] = __DECONST(char *, _PATH_RUNCOM);
442 		argv[2] = 0;
443 		syslog(LOG_ERR, "execv(%s, %p)\n", _PATH_BSHELL, argv);
444 		err = execv(_PATH_BSHELL, argv);
445 		syslog(LOG_ERR, "execv err=%d errno=%d", err, errno);
446 		sleep(2);
447 	}
448 	stall("can't exec %s for %s: %m", _PATH_BSHELL, _PATH_RUNCOM);
449 	launchd_exit(EXIT_FAILURE);
450 }
451 
452 static void
runcom_callback(void * obj,struct kevent * kev)453 runcom_callback(void *obj __attribute__((unused)), struct kevent *kev __attribute__((unused)))
454 {
455 	int status;
456 	struct timeval runcom_end_tv, runcom_total_tv;
457 	double sec;
458 
459 	gettimeofday(&runcom_end_tv, NULL);
460 	timersub(&runcom_end_tv, &runcom_start_tv, &runcom_total_tv);
461 	sec = runcom_total_tv.tv_sec;
462 	sec += (double)runcom_total_tv.tv_usec / (double)1000000;
463 	syslog(LOG_INFO, "%s finished in: %.3f seconds", _PATH_RUNCOM, sec);
464 
465 	if (launchd_assumes(waitpid(runcom_pid, &status, 0) == runcom_pid)) {
466 		runcom_pid = 0;
467 	} else {
468 		syslog(LOG_ERR, "going to single user mode");
469 		single_user_mode = true;
470 		return;
471 	}
472 
473 	if (WIFEXITED(status) && WEXITSTATUS(status) == EXIT_SUCCESS) {
474 #ifdef notyet
475 		logwtmp("~", "reboot", "");
476 #endif
477 		return;
478 	} else if (WIFSIGNALED(status) && (WTERMSIG(status) == SIGTERM || WTERMSIG(status) == SIGKILL)) {
479 		return;
480 	}
481 
482 	syslog(LOG_ERR, "%s on %s terminated abnormally, going to single user mode",
483 			_PATH_BSHELL, _PATH_RUNCOM);
484 	single_user_mode = true;
485 }
486 
487 /*
488  * Construct an argument vector from a command line.
489  */
490 char **
construct_argv(command)491 construct_argv(command)
492 	char *command;
493 {
494 	int argc = 0;
495 	char **argv = (char **) malloc(((strlen(command) + 1) / 2 + 1)
496 						* sizeof (char *));
497 	static const char separators[] = " \t";
498 
499 	if ((argv[argc++] = strtok(command, separators)) == 0)
500 		return 0;
501 	while ((argv[argc++] = strtok(NULL, separators)))
502 		continue;
503 	return argv;
504 }
505 
506 /*
507  * Deallocate a session descriptor.
508  */
509 
free_command(se_cmd_t * se_cmd)510 static void free_command(se_cmd_t *se_cmd)
511 {
512     if (se_cmd->path) {
513 	free(se_cmd->path);
514 	free(se_cmd->argv);
515     }
516 }
517 
518 void
session_free(session_t s)519 session_free(session_t s)
520 {
521 	TAILQ_REMOVE(&sessions, s, tqe);
522 	if (s->se_process) {
523 #ifdef notyet
524 		if (kevent_mod(s->se_process, EVFILT_PROC, EV_ADD,
525 					NOTE_EXIT, 0, &kqsimple_zombie_reaper) == -1)
526 			session_reap(s);
527 		else
528 			kill(s->se_process, SIGHUP);
529 #endif
530 	}
531 	free(s->se_device);
532 	free_command(&s->se_getty);
533 	free_command(&s->se_onerror);
534 	free_command(&s->se_onoption);
535 	free(s);
536 }
537 
setup_command(se_cmd_t * se_cmd,char * command,char * arg)538 static int setup_command(se_cmd_t *se_cmd, char *command, char *arg )
539 {
540 	char *commandWithArg;
541 
542 	asprintf(&commandWithArg, "%s %s", command, arg);
543 
544 	free_command(se_cmd);
545 
546 	se_cmd->path = commandWithArg;
547 	se_cmd->argv = construct_argv(commandWithArg);
548 	if (se_cmd->argv == NULL) {
549 		free(se_cmd->path);
550 		se_cmd->path = NULL;
551 		return 0;
552 	}
553 	return 1;
554 }
555 
556 /*
557  * Calculate getty and if useful window argv vectors.
558  */
559 static int
setupargv(sp,typ)560 setupargv(sp, typ)
561 	session_t sp;
562 	struct ttyent *typ;
563 {
564     const char *type;
565 
566     if ( !setup_command(&sp->se_getty, typ->ty_getty, typ->ty_name) )
567     {
568 	type = "getty";
569 	goto bad_args;
570     }
571 #if 0
572     if (typ->ty_onerror
573     && !setup_command(&sp->se_onerror, typ->ty_onerror, typ->ty_name) )
574     {
575 	type = "onerror";
576 	goto bad_args;
577     }
578 
579     if (typ->ty_onoption
580     && !setup_command(&sp->se_onoption, typ->ty_onoption, typ->ty_name) )
581     {
582 	type = "onoption";
583 	goto bad_args;
584     }
585 #endif
586     return 1;
587 
588 bad_args:
589     syslog(LOG_WARNING, "can't parse %s for port %s", type, sp->se_device);
590     return 0;
591 }
592 
593 
594 /*
595  * Allocate a new session descriptor.
596  */
597 void
session_new(session_index,typ)598 session_new(session_index, typ)
599 	int session_index;
600 	struct ttyent *typ;
601 {
602 	session_t s;
603 
604 	if ((typ->ty_status & TTY_ON) == 0 ||
605 	    typ->ty_name == 0 ||
606 	    typ->ty_getty == 0)
607 		return;
608 
609 	s = calloc(1, sizeof(struct init_session));
610 
611 	s->se_callback = session_callback;
612 	s->se_index = session_index;
613 
614 	TAILQ_INSERT_TAIL(&sessions, s, tqe);
615 
616 	asprintf(&s->se_device, "%s%s", _PATH_DEV, typ->ty_name);
617 
618 	if (setupargv(s, typ) == 0)
619 		session_free(s);
620 }
621 
622 static void
session_launch(session_t s)623 session_launch(session_t s)
624 {
625 	pid_t pid;
626 	sigset_t mask;
627 	se_cmd_t *se_cmd;
628 	const char *session_type = NULL;
629 	time_t current_time      = time(NULL);
630 	bool is_loginwindow = false;
631 
632 	// Setup the default values;
633 	switch (s->se_flags & SE_GETTY_LAUNCH) {
634 	case SE_ONOPTION:
635 		if (s->se_onoption.path) {
636 			se_cmd       = &s->se_onoption;
637 			session_type = "onoption";
638 			break;
639 		}
640 		/* No break */
641 	case SE_ONERROR:
642 		if (s->se_onerror.path) {
643 			se_cmd       = &s->se_onerror;
644 			session_type = "onerror";
645 			break;
646 		}
647 		/* No break */
648 	case SE_COMMON:
649 	default:
650 		se_cmd       = &s->se_getty;
651 		session_type = "getty";
652 		break;
653 	}
654 
655 	if (strcmp(se_cmd->argv[0], "/System/Library/CoreServices/loginwindow.app/Contents/MacOS/loginwindow") == 0)
656 		is_loginwindow = true;
657 
658 	pid = launchd_fork();
659 
660 	if (pid == -1) {
661 		syslog(LOG_ERR, "can't fork for %s on port %s: %m",
662 				session_type, s->se_device);
663 		return;
664 	}
665 
666 	if (pid) {
667 		s->se_process = pid;
668 		s->se_started = time(NULL);
669 		s->se_flags  &= ~SE_GETTY_LAUNCH; // clear down getty launch type
670 		if (kevent_mod(pid, EVFILT_PROC, EV_ADD, NOTE_EXIT, 0, &s->se_callback) == -1)
671 			session_reap(s);
672 		return;
673 	}
674 
675 	if (current_time > s->se_started &&
676 	    current_time - s->se_started < GETTY_SPACING) {
677 		syslog(LOG_WARNING, "%s repeating too quickly on port %s, sleeping",
678 		        session_type, s->se_device);
679 		sleep(GETTY_SLEEP);
680 	}
681 
682 	sigemptyset(&mask);
683 	sigprocmask(SIG_SETMASK, &mask, NULL);
684 
685 
686 	if (!is_loginwindow)
687 		launchd_SessionCreate();
688 
689 	execv(se_cmd->argv[0], se_cmd->argv);
690 	stall("can't exec %s '%s' for port %s: %m", session_type,
691 		se_cmd->argv[0], s->se_device);
692 	launchd_exit(EXIT_FAILURE);
693 }
694 
695 static void
session_callback(void * obj,struct kevent * kev)696 session_callback(void *obj, struct kevent *kev __attribute__((unused)))
697 {
698 	session_t s = obj;
699 
700 	session_reap(s);
701 	if (s->se_flags & SE_SHUTDOWN) {
702 		session_free(s);
703 	} else {
704 		session_launch(s);
705 	}
706 }
707 
708 static void
session_reap(session_t s)709 session_reap(session_t s)
710 {
711 	char *line;
712 	int status;
713 
714 	if (!launchd_assumes(waitpid(s->se_process, &status, 0) == s->se_process))
715 		return;
716 
717 	if (WIFSIGNALED(status)) {
718 		syslog(LOG_WARNING, "%s port %s exited abnormally: %s",
719 				s->se_getty.path, s->se_device, strsignal(WTERMSIG(status)));
720 		s->se_flags |= SE_ONERROR;
721 	} else if (WEXITSTATUS(status) == REALLY_EXIT_TO_CONSOLE) {
722 		/* WIFEXITED(status) assumed */
723 		s->se_flags |= SE_ONOPTION;
724 	} else {
725 		s->se_flags |= SE_ONERROR;
726 	}
727 
728 	s->se_process = 0;
729 	line = s->se_device + sizeof(_PATH_DEV) - 1;
730 
731 #ifdef notyet
732 	if (logout(line))
733 		logwtmp(line, "", "");
734 #endif
735 }
736 
737 /*
738  * This is an n-squared algorithm.  We hope it isn't run often...
739  */
740 void
update_ttys(void)741 update_ttys(void)
742 {
743 	session_t sp;
744 	struct ttyent *typ;
745 	int session_index = 0;
746 	int devlen;
747 
748 	devlen = sizeof(_PATH_DEV) - 1;
749 	while ((typ = getttyent())) {
750 		++session_index;
751 
752 		TAILQ_FOREACH(sp, &sessions, tqe) {
753 			if (strcmp(typ->ty_name, sp->se_device + devlen) == 0)
754 				break;
755 		}
756 
757 		if (sp == NULL) {
758 			session_new(session_index, typ);
759 			continue;
760 		}
761 
762 		if (sp->se_index != session_index) {
763 			syslog(LOG_INFO, "port %s changed utmp index from %d to %d",
764 			       sp->se_device, sp->se_index,
765 			       session_index);
766 			sp->se_index = session_index;
767 		}
768 
769 		if ((typ->ty_status & TTY_ON) == 0 ||
770 		    typ->ty_getty == 0) {
771 			session_free(sp);
772 			continue;
773 		}
774 
775 		sp->se_flags &= ~SE_SHUTDOWN;
776 
777 		if (setupargv(sp, typ) == 0) {
778 			syslog(LOG_WARNING, "can't parse getty for port %s",
779 				sp->se_device);
780 			session_free(sp);
781 		}
782 	}
783 
784 	endttyent();
785 }
786 
787 /*
788  * Block further logins.
789  */
790 void
catatonia(void)791 catatonia(void)
792 {
793 	session_t s;
794 
795 	TAILQ_FOREACH(s, &sessions, tqe)
796 		s->se_flags |= SE_SHUTDOWN;
797 }
798 
init_check_pid(pid_t p)799 bool init_check_pid(pid_t p)
800 {
801 	session_t s;
802 
803 	TAILQ_FOREACH(s, &sessions, tqe) {
804 		if (s->se_process == p)
805 			return true;
806 	}
807 
808 	if (single_user_pid == p)
809 		return true;
810 
811 	if (runcom_pid == p)
812 		return true;
813 
814 	return false;
815 }
816 
817 bool
should_fsck(void)818 should_fsck(void)
819 {
820 	struct statfs sfs;
821 	bool r = true;
822 
823 	if (launchd_assumes(statfs("/", &sfs) != -1)) {
824 		if (!(sfs.f_flags & MNT_RDONLY)) {
825 			r = false;
826 		}
827 	}
828 
829 	return r;
830 }
831