37 */
38
39#ifndef lint
40static char copyright[] =
41"@(#) Copyright (c) 1991, 1993\n\
42 The Regents of the University of California. All rights reserved.\n";
43#endif /* not lint */
44
45#ifndef lint
46static char sccsid[] = "@(#)init.c 8.1 (Berkeley) 7/15/93";
47#endif /* not lint */
48
49#include <sys/param.h>
50#include <sys/ioctl.h>
51#include <sys/mount.h>
52#include <sys/sysctl.h>
53#include <sys/wait.h>
54#include <sys/types.h>
55#include <sys/stat.h>
56
57#include <db.h>
58#include <errno.h>
59#include <fcntl.h>
60#include <libutil.h>
61#include <signal.h>
62#include <stdio.h>
63#include <stdlib.h>
64#include <string.h>
65#include <syslog.h>
66#include <time.h>
67#include <ttyent.h>
68#include <unistd.h>
69#include <sys/reboot.h>
70#include <err.h>
71
72#ifdef __STDC__
73#include <stdarg.h>
74#else
75#include <varargs.h>
76#endif
77
78#ifdef SECURE
79#include <pwd.h>
80#endif
81
82#ifdef LOGIN_CAP
83#include <login_cap.h>
84#endif
85
86#include "pathnames.h"
87
88/*
89 * Sleep times; used to prevent thrashing.
90 */
91#define GETTY_SPACING 5 /* N secs minimum getty spacing */
92#define GETTY_SLEEP 30 /* sleep N secs after spacing problem */
93#define GETTY_NSPACE 3 /* max. spacing count to bring reaction */
94#define WINDOW_WAIT 3 /* wait N secs after starting window */
95#define STALL_TIMEOUT 30 /* wait N secs after warning */
96#define DEATH_WATCH 10 /* wait N secs for procs to die */
97#define DEATH_SCRIPT 120 /* wait for 2mn for /etc/rc.shutdown */
98#define RESOURCE_RC "daemon"
99#define RESOURCE_WINDOW "default"
100#define RESOURCE_GETTY "default"
101
102void handle __P((sig_t, ...));
103void delset __P((sigset_t *, ...));
104
105void stall __P((char *, ...));
106void warning __P((char *, ...));
107void emergency __P((char *, ...));
108void disaster __P((int));
109void badsys __P((int));
110int runshutdown __P((void));
111
112/*
113 * We really need a recursive typedef...
114 * The following at least guarantees that the return type of (*state_t)()
115 * is sufficiently wide to hold a function pointer.
116 */
117typedef long (*state_func_t) __P((void));
118typedef state_func_t (*state_t) __P((void));
119
120state_func_t single_user __P((void));
121state_func_t runcom __P((void));
122state_func_t read_ttys __P((void));
123state_func_t multi_user __P((void));
124state_func_t clean_ttys __P((void));
125state_func_t catatonia __P((void));
126state_func_t death __P((void));
127
128enum { AUTOBOOT, FASTBOOT } runcom_mode = AUTOBOOT;
129#define FALSE 0
130#define TRUE 1
131
132int Reboot = FALSE;
133
134int devfs;
135
136void transition __P((state_t));
137state_t requested_transition = runcom;
138
139void setctty __P((char *));
140
141typedef struct init_session {
142 int se_index; /* index of entry in ttys file */
143 pid_t se_process; /* controlling process */
144 time_t se_started; /* used to avoid thrashing */
145 int se_flags; /* status of session */
146#define SE_SHUTDOWN 0x1 /* session won't be restarted */
147 int se_nspace; /* spacing count */
148 char *se_device; /* filename of port */
149 char *se_getty; /* what to run on that port */
150 char *se_getty_argv_space; /* pre-parsed argument array space */
151 char **se_getty_argv; /* pre-parsed argument array */
152 char *se_window; /* window system (started only once) */
153 char *se_window_argv_space; /* pre-parsed argument array space */
154 char **se_window_argv; /* pre-parsed argument array */
155 char *se_type; /* default terminal type */
156 struct init_session *se_prev;
157 struct init_session *se_next;
158} session_t;
159
160void free_session __P((session_t *));
161session_t *new_session __P((session_t *, int, struct ttyent *));
162session_t *sessions;
163
164char **construct_argv __P((char *));
165void start_window_system __P((session_t *));
166void collect_child __P((pid_t));
167pid_t start_getty __P((session_t *));
168void transition_handler __P((int));
169void alrm_handler __P((int));
170void setsecuritylevel __P((int));
171int getsecuritylevel __P((void));
172int setupargv __P((session_t *, struct ttyent *));
173#ifdef LOGIN_CAP
174void setprocresources __P((const char *));
175#endif
176int clang;
177
178void clear_session_logs __P((session_t *));
179
180int start_session_db __P((void));
181void add_session __P((session_t *));
182void del_session __P((session_t *));
183session_t *find_session __P((pid_t));
184DB *session_db;
185
186/*
187 * The mother of all processes.
188 */
189int
190main(argc, argv)
191 int argc;
192 char **argv;
193{
194 int c;
195 struct sigaction sa;
196 sigset_t mask;
197
198
199 /* Dispose of random users. */
200 if (getuid() != 0)
201 errx(1, "%s", strerror(EPERM));
202
203 /* System V users like to reexec init. */
204 if (getpid() != 1)
205 errx(1, "already running");
206
207 /*
208 * Note that this does NOT open a file...
209 * Does 'init' deserve its own facility number?
210 */
211 openlog("init", LOG_CONS|LOG_ODELAY, LOG_AUTH);
212
213 /*
214 * Create an initial session.
215 */
216 if (setsid() < 0)
217 warning("initial setsid() failed: %m");
218
219 /*
220 * Establish an initial user so that programs running
221 * single user do not freak out and die (like passwd).
222 */
223 if (setlogin("root") < 0)
224 warning("setlogin() failed: %m");
225
226 /*
227 * This code assumes that we always get arguments through flags,
228 * never through bits set in some random machine register.
229 */
230 while ((c = getopt(argc, argv, "dsf")) != -1)
231 switch (c) {
232 case 'd':
233 devfs = 1;
234 break;
235 case 's':
236 requested_transition = single_user;
237 break;
238 case 'f':
239 runcom_mode = FASTBOOT;
240 break;
241 default:
242 warning("unrecognized flag '-%c'", c);
243 break;
244 }
245
246 if (optind != argc)
247 warning("ignoring excess arguments");
248
249 if (devfs) {
250 mount("devfs", "/dev", MNT_NOEXEC|MNT_RDONLY, 0);
251 }
252
253 /*
254 * We catch or block signals rather than ignore them,
255 * so that they get reset on exec.
256 */
257 handle(badsys, SIGSYS, 0);
258 handle(disaster, SIGABRT, SIGFPE, SIGILL, SIGSEGV,
259 SIGBUS, SIGXCPU, SIGXFSZ, 0);
260 handle(transition_handler, SIGHUP, SIGINT, SIGTERM, SIGTSTP, 0);
261 handle(alrm_handler, SIGALRM, 0);
262 sigfillset(&mask);
263 delset(&mask, SIGABRT, SIGFPE, SIGILL, SIGSEGV, SIGBUS, SIGSYS,
264 SIGXCPU, SIGXFSZ, SIGHUP, SIGINT, SIGTERM, SIGTSTP, SIGALRM, 0);
265 sigprocmask(SIG_SETMASK, &mask, (sigset_t *) 0);
266 sigemptyset(&sa.sa_mask);
267 sa.sa_flags = 0;
268 sa.sa_handler = SIG_IGN;
269 (void) sigaction(SIGTTIN, &sa, (struct sigaction *)0);
270 (void) sigaction(SIGTTOU, &sa, (struct sigaction *)0);
271
272 /*
273 * Paranoia.
274 */
275 close(0);
276 close(1);
277 close(2);
278
279 /*
280 * Start the state machine.
281 */
282 transition(requested_transition);
283
284 /*
285 * Should never reach here.
286 */
287 return 1;
288}
289
290/*
291 * Associate a function with a signal handler.
292 */
293void
294#ifdef __STDC__
295handle(sig_t handler, ...)
296#else
297handle(va_alist)
298 va_dcl
299#endif
300{
301 int sig;
302 struct sigaction sa;
|
304 va_list ap;
305#ifndef __STDC__
306 sig_t handler;
307
308 va_start(ap);
309 handler = va_arg(ap, sig_t);
310#else
311 va_start(ap, handler);
312#endif
313
314 sa.sa_handler = handler;
315 sigfillset(&mask_everything);
316
317 while ((sig = va_arg(ap, int)) != NULL) {
318 sa.sa_mask = mask_everything;
319 /* XXX SA_RESTART? */
320 sa.sa_flags = sig == SIGCHLD ? SA_NOCLDSTOP : 0;
321 sigaction(sig, &sa, (struct sigaction *) 0);
322 }
323 va_end(ap);
324}
325
326/*
327 * Delete a set of signals from a mask.
328 */
329void
330#ifdef __STDC__
331delset(sigset_t *maskp, ...)
332#else
333delset(va_alist)
334 va_dcl
335#endif
336{
337 int sig;
338 va_list ap;
339#ifndef __STDC__
340 sigset_t *maskp;
341
342 va_start(ap);
343 maskp = va_arg(ap, sigset_t *);
344#else
345 va_start(ap, maskp);
346#endif
347
348 while ((sig = va_arg(ap, int)) != NULL)
349 sigdelset(maskp, sig);
350 va_end(ap);
351}
352
353/*
354 * Log a message and sleep for a while (to give someone an opportunity
355 * to read it and to save log or hardcopy output if the problem is chronic).
356 * NB: should send a message to the session logger to avoid blocking.
357 */
358void
359#ifdef __STDC__
360stall(char *message, ...)
361#else
362stall(va_alist)
363 va_dcl
364#endif
365{
366 va_list ap;
367#ifndef __STDC__
368 char *message;
369
370 va_start(ap);
371 message = va_arg(ap, char *);
372#else
373 va_start(ap, message);
374#endif
375
376 vsyslog(LOG_ALERT, message, ap);
377 va_end(ap);
378 sleep(STALL_TIMEOUT);
379}
380
381/*
382 * Like stall(), but doesn't sleep.
383 * If cpp had variadic macros, the two functions could be #defines for another.
384 * NB: should send a message to the session logger to avoid blocking.
385 */
386void
387#ifdef __STDC__
388warning(char *message, ...)
389#else
390warning(va_alist)
391 va_dcl
392#endif
393{
394 va_list ap;
395#ifndef __STDC__
396 char *message;
397
398 va_start(ap);
399 message = va_arg(ap, char *);
400#else
401 va_start(ap, message);
402#endif
403
404 vsyslog(LOG_ALERT, message, ap);
405 va_end(ap);
406}
407
408/*
409 * Log an emergency message.
410 * NB: should send a message to the session logger to avoid blocking.
411 */
412void
413#ifdef __STDC__
414emergency(char *message, ...)
415#else
416emergency(va_alist)
417 va_dcl
418#endif
419{
420 va_list ap;
421#ifndef __STDC__
422 char *message;
423
424 va_start(ap);
425 message = va_arg(ap, char *);
426#else
427 va_start(ap, message);
428#endif
429
430 vsyslog(LOG_EMERG, message, ap);
431 va_end(ap);
432}
433
434/*
435 * Catch a SIGSYS signal.
436 *
437 * These may arise if a system does not support sysctl.
438 * We tolerate up to 25 of these, then throw in the towel.
439 */
440void
441badsys(sig)
442 int sig;
443{
444 static int badcount = 0;
445
446 if (badcount++ < 25)
447 return;
448 disaster(sig);
449}
450
451/*
452 * Catch an unexpected signal.
453 */
454void
455disaster(sig)
456 int sig;
457{
458 emergency("fatal signal: %s",
459 (unsigned)sig < NSIG ? sys_siglist[sig] : "unknown signal");
460
461 sleep(STALL_TIMEOUT);
462 _exit(sig); /* reboot */
463}
464
465/*
466 * Get the security level of the kernel.
467 */
468int
469getsecuritylevel()
470{
471#ifdef KERN_SECURELVL
472 int name[2], curlevel;
473 size_t len;
474 extern int errno;
475
476 name[0] = CTL_KERN;
477 name[1] = KERN_SECURELVL;
478 len = sizeof curlevel;
479 if (sysctl(name, 2, &curlevel, &len, NULL, 0) == -1) {
480 emergency("cannot get kernel security level: %s",
481 strerror(errno));
482 return (-1);
483 }
484 return (curlevel);
485#else
486 return (-1);
487#endif
488}
489
490/*
491 * Set the security level of the kernel.
492 */
493void
494setsecuritylevel(newlevel)
495 int newlevel;
496{
497#ifdef KERN_SECURELVL
498 int name[2], curlevel;
499 extern int errno;
500
501 curlevel = getsecuritylevel();
502 if (newlevel == curlevel)
503 return;
504 name[0] = CTL_KERN;
505 name[1] = KERN_SECURELVL;
506 if (sysctl(name, 2, NULL, NULL, &newlevel, sizeof newlevel) == -1) {
507 emergency(
508 "cannot change kernel security level from %d to %d: %s",
509 curlevel, newlevel, strerror(errno));
510 return;
511 }
512#ifdef SECURE
513 warning("kernel security level changed from %d to %d",
514 curlevel, newlevel);
515#endif
516#endif
517}
518
519/*
520 * Change states in the finite state machine.
521 * The initial state is passed as an argument.
522 */
523void
524transition(s)
525 state_t s;
526{
527 for (;;)
528 s = (state_t) (*s)();
529}
530
531/*
532 * Close out the accounting files for a login session.
533 * NB: should send a message to the session logger to avoid blocking.
534 */
535void
536clear_session_logs(sp)
537 session_t *sp;
538{
539 char *line = sp->se_device + sizeof(_PATH_DEV) - 1;
540
541 if (logout(line))
542 logwtmp(line, "", "");
543}
544
545/*
546 * Start a session and allocate a controlling terminal.
547 * Only called by children of init after forking.
548 */
549void
550setctty(name)
551 char *name;
552{
553 int fd;
554
555 (void) revoke(name);
556 if ((fd = open(name, O_RDWR)) == -1) {
557 stall("can't open %s: %m", name);
558 _exit(1);
559 }
560 if (login_tty(fd) == -1) {
561 stall("can't get %s for controlling terminal: %m", name);
562 _exit(1);
563 }
564}
565
566/*
567 * Bring the system up single user.
568 */
569state_func_t
570single_user()
571{
572 pid_t pid, wpid;
573 int status;
574 sigset_t mask;
575 char *shell = _PATH_BSHELL;
576 char *argv[2];
577#ifdef SECURE
578 struct ttyent *typ;
579 struct passwd *pp;
580 static const char banner[] =
581 "Enter root password, or ^D to go multi-user\n";
582 char *clear, *password;
583#endif
584
585 /*
586 * If the kernel is in secure mode, downgrade it to insecure mode.
587 */
588 if (getsecuritylevel() > 0)
589 setsecuritylevel(0);
590
591 if (Reboot) {
592 /* Instead of going single user, let's halt the machine */
593 sync();
594 alarm(2);
595 pause();
596 reboot(RB_AUTOBOOT);
597 _exit(0);
598 }
599
600 if ((pid = fork()) == 0) {
601 /*
602 * Start the single user session.
603 */
604 setctty(_PATH_CONSOLE);
605
606#ifdef SECURE
607 /*
608 * Check the root password.
609 * We don't care if the console is 'on' by default;
610 * it's the only tty that can be 'off' and 'secure'.
611 */
612 typ = getttynam("console");
613 pp = getpwnam("root");
614 if (typ && (typ->ty_status & TTY_SECURE) == 0 && pp && *pp->pw_passwd) {
615 write(2, banner, sizeof banner - 1);
616 for (;;) {
617 clear = getpass("Password:");
618 if (clear == 0 || *clear == '\0')
619 _exit(0);
620 password = crypt(clear, pp->pw_passwd);
621 bzero(clear, _PASSWORD_LEN);
622 if (strcmp(password, pp->pw_passwd) == 0)
623 break;
624 warning("single-user login failed\n");
625 }
626 }
627 endttyent();
628 endpwent();
629#endif /* SECURE */
630
631#ifdef DEBUGSHELL
632 {
633 char altshell[128], *cp = altshell;
634 int num;
635
636#define SHREQUEST \
637 "Enter full pathname of shell or RETURN for " _PATH_BSHELL ": "
638 (void)write(STDERR_FILENO,
639 SHREQUEST, sizeof(SHREQUEST) - 1);
640 while ((num = read(STDIN_FILENO, cp, 1)) != -1 &&
641 num != 0 && *cp != '\n' && cp < &altshell[127])
642 cp++;
643 *cp = '\0';
644 if (altshell[0] != '\0')
645 shell = altshell;
646 }
647#endif /* DEBUGSHELL */
648
649 /*
650 * Unblock signals.
651 * We catch all the interesting ones,
652 * and those are reset to SIG_DFL on exec.
653 */
654 sigemptyset(&mask);
655 sigprocmask(SIG_SETMASK, &mask, (sigset_t *) 0);
656
657 /*
658 * Fire off a shell.
659 * If the default one doesn't work, try the Bourne shell.
660 */
661 argv[0] = "-sh";
662 argv[1] = 0;
663 execv(shell, argv);
664 emergency("can't exec %s for single user: %m", shell);
665 execv(_PATH_BSHELL, argv);
666 emergency("can't exec %s for single user: %m", _PATH_BSHELL);
667 sleep(STALL_TIMEOUT);
668 _exit(1);
669 }
670
671 if (pid == -1) {
672 /*
673 * We are seriously hosed. Do our best.
674 */
675 emergency("can't fork single-user shell, trying again");
676 while (waitpid(-1, (int *) 0, WNOHANG) > 0)
677 continue;
678 return (state_func_t) single_user;
679 }
680
681 requested_transition = 0;
682 do {
683 if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1)
684 collect_child(wpid);
685 if (wpid == -1) {
686 if (errno == EINTR)
687 continue;
688 warning("wait for single-user shell failed: %m; restarting");
689 return (state_func_t) single_user;
690 }
691 if (wpid == pid && WIFSTOPPED(status)) {
692 warning("init: shell stopped, restarting\n");
693 kill(pid, SIGCONT);
694 wpid = -1;
695 }
696 } while (wpid != pid && !requested_transition);
697
698 if (requested_transition)
699 return (state_func_t) requested_transition;
700
701 if (!WIFEXITED(status)) {
702 if (WTERMSIG(status) == SIGKILL) {
703 /*
704 * reboot(8) killed shell?
705 */
706 warning("single user shell terminated.");
707 sleep(STALL_TIMEOUT);
708 _exit(0);
709 } else {
710 warning("single user shell terminated, restarting");
711 return (state_func_t) single_user;
712 }
713 }
714
715 runcom_mode = FASTBOOT;
716 return (state_func_t) runcom;
717}
718
719/*
720 * Run the system startup script.
721 */
722state_func_t
723runcom()
724{
725 pid_t pid, wpid;
726 int status;
727 char *argv[4];
728 struct sigaction sa;
729
730 if ((pid = fork()) == 0) {
731 sigemptyset(&sa.sa_mask);
732 sa.sa_flags = 0;
733 sa.sa_handler = SIG_IGN;
734 (void) sigaction(SIGTSTP, &sa, (struct sigaction *)0);
735 (void) sigaction(SIGHUP, &sa, (struct sigaction *)0);
736
737 setctty(_PATH_CONSOLE);
738
739 argv[0] = "sh";
740 argv[1] = _PATH_RUNCOM;
741 argv[2] = runcom_mode == AUTOBOOT ? "autoboot" : 0;
742 argv[3] = 0;
743
744 sigprocmask(SIG_SETMASK, &sa.sa_mask, (sigset_t *) 0);
745
746#ifdef LOGIN_CAP
747 setprocresources(RESOURCE_RC);
748#endif
749 execv(_PATH_BSHELL, argv);
750 stall("can't exec %s for %s: %m", _PATH_BSHELL, _PATH_RUNCOM);
751 _exit(1); /* force single user mode */
752 }
753
754 if (pid == -1) {
755 emergency("can't fork for %s on %s: %m",
756 _PATH_BSHELL, _PATH_RUNCOM);
757 while (waitpid(-1, (int *) 0, WNOHANG) > 0)
758 continue;
759 sleep(STALL_TIMEOUT);
760 return (state_func_t) single_user;
761 }
762
763 /*
764 * Copied from single_user(). This is a bit paranoid.
765 */
766 do {
767 if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1)
768 collect_child(wpid);
769 if (wpid == -1) {
770 if (errno == EINTR)
771 continue;
772 warning("wait for %s on %s failed: %m; going to single user mode",
773 _PATH_BSHELL, _PATH_RUNCOM);
774 return (state_func_t) single_user;
775 }
776 if (wpid == pid && WIFSTOPPED(status)) {
777 warning("init: %s on %s stopped, restarting\n",
778 _PATH_BSHELL, _PATH_RUNCOM);
779 kill(pid, SIGCONT);
780 wpid = -1;
781 }
782 } while (wpid != pid);
783
784 if (WIFSIGNALED(status) && WTERMSIG(status) == SIGTERM &&
785 requested_transition == catatonia) {
786 /* /etc/rc executed /sbin/reboot; wait for the end quietly */
787 sigset_t s;
788
789 sigfillset(&s);
790 for (;;)
791 sigsuspend(&s);
792 }
793
794 if (!WIFEXITED(status)) {
795 warning("%s on %s terminated abnormally, going to single user mode",
796 _PATH_BSHELL, _PATH_RUNCOM);
797 return (state_func_t) single_user;
798 }
799
800 if (WEXITSTATUS(status))
801 return (state_func_t) single_user;
802
803 runcom_mode = AUTOBOOT; /* the default */
804 /* NB: should send a message to the session logger to avoid blocking. */
805 logwtmp("~", "reboot", "");
806 return (state_func_t) read_ttys;
807}
808
809/*
810 * Open the session database.
811 *
812 * NB: We could pass in the size here; is it necessary?
813 */
814int
815start_session_db()
816{
817 if (session_db && (*session_db->close)(session_db))
818 emergency("session database close: %s", strerror(errno));
819 if ((session_db = dbopen(NULL, O_RDWR, 0, DB_HASH, NULL)) == 0) {
820 emergency("session database open: %s", strerror(errno));
821 return (1);
822 }
823 return (0);
824
825}
826
827/*
828 * Add a new login session.
829 */
830void
831add_session(sp)
832 session_t *sp;
833{
834 DBT key;
835 DBT data;
836
837 key.data = &sp->se_process;
838 key.size = sizeof sp->se_process;
839 data.data = &sp;
840 data.size = sizeof sp;
841
842 if ((*session_db->put)(session_db, &key, &data, 0))
843 emergency("insert %d: %s", sp->se_process, strerror(errno));
844}
845
846/*
847 * Delete an old login session.
848 */
849void
850del_session(sp)
851 session_t *sp;
852{
853 DBT key;
854
855 key.data = &sp->se_process;
856 key.size = sizeof sp->se_process;
857
858 if ((*session_db->del)(session_db, &key, 0))
859 emergency("delete %d: %s", sp->se_process, strerror(errno));
860}
861
862/*
863 * Look up a login session by pid.
864 */
865session_t *
866#ifdef __STDC__
867find_session(pid_t pid)
868#else
869find_session(pid)
870 pid_t pid;
871#endif
872{
873 DBT key;
874 DBT data;
875 session_t *ret;
876
877 key.data = &pid;
878 key.size = sizeof pid;
879 if ((*session_db->get)(session_db, &key, &data, 0) != 0)
880 return 0;
881 bcopy(data.data, (char *)&ret, sizeof(ret));
882 return ret;
883}
884
885/*
886 * Construct an argument vector from a command line.
887 */
888char **
889construct_argv(command)
890 char *command;
891{
892 char *strk (char *);
893 register int argc = 0;
894 register char **argv = (char **) malloc(((strlen(command) + 1) / 2 + 1)
895 * sizeof (char *));
896
897 if ((argv[argc++] = strk(command)) == 0)
898 return 0;
899 while ((argv[argc++] = strk((char *) 0)) != NULL)
900 continue;
901 return argv;
902}
903
904/*
905 * Deallocate a session descriptor.
906 */
907void
908free_session(sp)
909 register session_t *sp;
910{
911 free(sp->se_device);
912 if (sp->se_getty) {
913 free(sp->se_getty);
914 free(sp->se_getty_argv_space);
915 free(sp->se_getty_argv);
916 }
917 if (sp->se_window) {
918 free(sp->se_window);
919 free(sp->se_window_argv_space);
920 free(sp->se_window_argv);
921 }
922 if (sp->se_type)
923 free(sp->se_type);
924 free(sp);
925}
926
927/*
928 * Allocate a new session descriptor.
929 */
930session_t *
931new_session(sprev, session_index, typ)
932 session_t *sprev;
933 int session_index;
934 register struct ttyent *typ;
935{
936 register session_t *sp;
937 int fd;
938
939 if ((typ->ty_status & TTY_ON) == 0 ||
940 typ->ty_name == 0 ||
941 typ->ty_getty == 0)
942 return 0;
943
944 sp = (session_t *) calloc(1, sizeof (session_t));
945
946 sp->se_index = session_index;
947
948 sp->se_device = malloc(sizeof(_PATH_DEV) + strlen(typ->ty_name));
949 (void) sprintf(sp->se_device, "%s%s", _PATH_DEV, typ->ty_name);
950
951 /*
952 * Attempt to open the device, if we get "device not configured"
953 * then don't add the device to the session list.
954 */
955 if ((fd = open(sp->se_device, O_RDONLY | O_NONBLOCK, 0)) < 0) {
956 if (errno == ENXIO) {
957 free_session(sp);
958 return (0);
959 }
960 } else
961 close(fd);
962
963 if (setupargv(sp, typ) == 0) {
964 free_session(sp);
965 return (0);
966 }
967
968 sp->se_next = 0;
969 if (sprev == 0) {
970 sessions = sp;
971 sp->se_prev = 0;
972 } else {
973 sprev->se_next = sp;
974 sp->se_prev = sprev;
975 }
976
977 return sp;
978}
979
980/*
981 * Calculate getty and if useful window argv vectors.
982 */
983int
984setupargv(sp, typ)
985 session_t *sp;
986 struct ttyent *typ;
987{
988
989 if (sp->se_getty) {
990 free(sp->se_getty);
991 free(sp->se_getty_argv_space);
992 free(sp->se_getty_argv);
993 }
994 sp->se_getty = malloc(strlen(typ->ty_getty) + strlen(typ->ty_name) + 2);
995 (void) sprintf(sp->se_getty, "%s %s", typ->ty_getty, typ->ty_name);
996 sp->se_getty_argv_space = strdup(sp->se_getty);
997 sp->se_getty_argv = construct_argv(sp->se_getty_argv_space);
998 if (sp->se_getty_argv == 0) {
999 warning("can't parse getty for port %s", sp->se_device);
1000 free(sp->se_getty);
1001 free(sp->se_getty_argv_space);
1002 sp->se_getty = sp->se_getty_argv_space = 0;
1003 return (0);
1004 }
1005 if (sp->se_window) {
1006 free(sp->se_window);
1007 free(sp->se_window_argv_space);
1008 free(sp->se_window_argv);
1009 }
1010 sp->se_window = sp->se_window_argv_space = 0;
1011 sp->se_window_argv = 0;
1012 if (typ->ty_window) {
1013 sp->se_window = strdup(typ->ty_window);
1014 sp->se_window_argv_space = strdup(sp->se_window);
1015 sp->se_window_argv = construct_argv(sp->se_window_argv_space);
1016 if (sp->se_window_argv == 0) {
1017 warning("can't parse window for port %s",
1018 sp->se_device);
1019 free(sp->se_window_argv_space);
1020 free(sp->se_window);
1021 sp->se_window = sp->se_window_argv_space = 0;
1022 return (0);
1023 }
1024 }
1025 if (sp->se_type)
1026 free(sp->se_type);
1027 sp->se_type = typ->ty_type ? strdup(typ->ty_type) : 0;
1028 return (1);
1029}
1030
1031/*
1032 * Walk the list of ttys and create sessions for each active line.
1033 */
1034state_func_t
1035read_ttys()
1036{
1037 int session_index = 0;
1038 register session_t *sp, *snext;
1039 register struct ttyent *typ;
1040
1041 /*
1042 * Destroy any previous session state.
1043 * There shouldn't be any, but just in case...
1044 */
1045 for (sp = sessions; sp; sp = snext) {
1046 if (sp->se_process)
1047 clear_session_logs(sp);
1048 snext = sp->se_next;
1049 free_session(sp);
1050 }
1051 sessions = 0;
1052 if (start_session_db())
1053 return (state_func_t) single_user;
1054
1055 /*
1056 * Allocate a session entry for each active port.
1057 * Note that sp starts at 0.
1058 */
1059 while ((typ = getttyent()) != NULL)
1060 if ((snext = new_session(sp, ++session_index, typ)) != NULL)
1061 sp = snext;
1062
1063 endttyent();
1064
1065 return (state_func_t) multi_user;
1066}
1067
1068/*
1069 * Start a window system running.
1070 */
1071void
1072start_window_system(sp)
1073 session_t *sp;
1074{
1075 pid_t pid;
1076 sigset_t mask;
1077 char term[64], *env[2];
1078
1079 if ((pid = fork()) == -1) {
1080 emergency("can't fork for window system on port %s: %m",
1081 sp->se_device);
1082 /* hope that getty fails and we can try again */
1083 return;
1084 }
1085
1086 if (pid)
1087 return;
1088
1089 sigemptyset(&mask);
1090 sigprocmask(SIG_SETMASK, &mask, (sigset_t *) 0);
1091
1092 if (setsid() < 0)
1093 emergency("setsid failed (window) %m");
1094
1095#ifdef LOGIN_CAP
1096 setprocresources(RESOURCE_WINDOW);
1097#endif
1098 if (sp->se_type) {
1099 /* Don't use malloc after fork */
1100 strcpy(term, "TERM=");
1101 strncat(term, sp->se_type, sizeof(term) - 6);
1102 env[0] = term;
1103 env[1] = 0;
1104 }
1105 else
1106 env[0] = 0;
1107 execve(sp->se_window_argv[0], sp->se_window_argv, env);
1108 stall("can't exec window system '%s' for port %s: %m",
1109 sp->se_window_argv[0], sp->se_device);
1110 _exit(1);
1111}
1112
1113/*
1114 * Start a login session running.
1115 */
1116pid_t
1117start_getty(sp)
1118 session_t *sp;
1119{
1120 pid_t pid;
1121 sigset_t mask;
1122 time_t current_time = time((time_t *) 0);
1123 int too_quick = 0;
1124 char term[64], *env[2];
1125
1126 if (current_time >= sp->se_started &&
1127 current_time - sp->se_started < GETTY_SPACING) {
1128 if (++sp->se_nspace > GETTY_NSPACE) {
1129 sp->se_nspace = 0;
1130 too_quick = 1;
1131 }
1132 } else
1133 sp->se_nspace = 0;
1134
1135 /*
1136 * fork(), not vfork() -- we can't afford to block.
1137 */
1138 if ((pid = fork()) == -1) {
1139 emergency("can't fork for getty on port %s: %m", sp->se_device);
1140 return -1;
1141 }
1142
1143 if (pid)
1144 return pid;
1145
1146 if (too_quick) {
1147 warning("getty repeating too quickly on port %s, sleeping %d secs",
1148 sp->se_device, GETTY_SLEEP);
1149 sleep((unsigned) GETTY_SLEEP);
1150 }
1151
1152 if (sp->se_window) {
1153 start_window_system(sp);
1154 sleep(WINDOW_WAIT);
1155 }
1156
1157 sigemptyset(&mask);
1158 sigprocmask(SIG_SETMASK, &mask, (sigset_t *) 0);
1159
1160#ifdef LOGIN_CAP
1161 setprocresources(RESOURCE_GETTY);
1162#endif
1163 if (sp->se_type) {
1164 /* Don't use malloc after fork */
1165 strcpy(term, "TERM=");
1166 strncat(term, sp->se_type, sizeof(term) - 6);
1167 env[0] = term;
1168 env[1] = 0;
1169 }
1170 else
1171 env[0] = 0;
1172 execve(sp->se_getty_argv[0], sp->se_getty_argv, env);
1173 stall("can't exec getty '%s' for port %s: %m",
1174 sp->se_getty_argv[0], sp->se_device);
1175 _exit(1);
1176}
1177
1178/*
1179 * Collect exit status for a child.
1180 * If an exiting login, start a new login running.
1181 */
1182void
1183#ifdef __STDC__
1184collect_child(pid_t pid)
1185#else
1186collect_child(pid)
1187 pid_t pid;
1188#endif
1189{
1190 register session_t *sp, *sprev, *snext;
1191
1192 if (! sessions)
1193 return;
1194
1195 if (! (sp = find_session(pid)))
1196 return;
1197
1198 clear_session_logs(sp);
1199 del_session(sp);
1200 sp->se_process = 0;
1201
1202 if (sp->se_flags & SE_SHUTDOWN) {
1203 if ((sprev = sp->se_prev) != NULL)
1204 sprev->se_next = sp->se_next;
1205 else
1206 sessions = sp->se_next;
1207 if ((snext = sp->se_next) != NULL)
1208 snext->se_prev = sp->se_prev;
1209 free_session(sp);
1210 return;
1211 }
1212
1213 if ((pid = start_getty(sp)) == -1) {
1214 /* serious trouble */
1215 requested_transition = clean_ttys;
1216 return;
1217 }
1218
1219 sp->se_process = pid;
1220 sp->se_started = time((time_t *) 0);
1221 add_session(sp);
1222}
1223
1224/*
1225 * Catch a signal and request a state transition.
1226 */
1227void
1228transition_handler(sig)
1229 int sig;
1230{
1231
1232 switch (sig) {
1233 case SIGHUP:
1234 requested_transition = clean_ttys;
1235 break;
1236 case SIGINT:
1237 Reboot = TRUE;
1238 case SIGTERM:
1239 requested_transition = death;
1240 break;
1241 case SIGTSTP:
1242 requested_transition = catatonia;
1243 break;
1244 default:
1245 requested_transition = 0;
1246 break;
1247 }
1248}
1249
1250/*
1251 * Take the system multiuser.
1252 */
1253state_func_t
1254multi_user()
1255{
1256 pid_t pid;
1257 register session_t *sp;
1258
1259 requested_transition = 0;
1260
1261 /*
1262 * If the administrator has not set the security level to -1
1263 * to indicate that the kernel should not run multiuser in secure
1264 * mode, and the run script has not set a higher level of security
1265 * than level 1, then put the kernel into secure mode.
1266 */
1267 if (getsecuritylevel() == 0)
1268 setsecuritylevel(1);
1269
1270 for (sp = sessions; sp; sp = sp->se_next) {
1271 if (sp->se_process)
1272 continue;
1273 if ((pid = start_getty(sp)) == -1) {
1274 /* serious trouble */
1275 requested_transition = clean_ttys;
1276 break;
1277 }
1278 sp->se_process = pid;
1279 sp->se_started = time((time_t *) 0);
1280 add_session(sp);
1281 }
1282
1283 while (!requested_transition)
1284 if ((pid = waitpid(-1, (int *) 0, 0)) != -1)
1285 collect_child(pid);
1286
1287 return (state_func_t) requested_transition;
1288}
1289
1290/*
1291 * This is an n-squared algorithm. We hope it isn't run often...
1292 */
1293state_func_t
1294clean_ttys()
1295{
1296 register session_t *sp, *sprev;
1297 register struct ttyent *typ;
1298 register int session_index = 0;
1299 register int devlen;
1300 char *old_getty, *old_window, *old_type;
1301
1302 if (! sessions)
1303 return (state_func_t) multi_user;
1304
1305 devlen = sizeof(_PATH_DEV) - 1;
1306 while ((typ = getttyent()) != NULL) {
1307 ++session_index;
1308
1309 for (sprev = 0, sp = sessions; sp; sprev = sp, sp = sp->se_next)
1310 if (strcmp(typ->ty_name, sp->se_device + devlen) == 0)
1311 break;
1312
1313 if (sp) {
1314 if (sp->se_index != session_index) {
1315 warning("port %s changed utmp index from %d to %d",
1316 sp->se_device, sp->se_index,
1317 session_index);
1318 sp->se_index = session_index;
1319 }
1320 if ((typ->ty_status & TTY_ON) == 0 ||
1321 typ->ty_getty == 0) {
1322 sp->se_flags |= SE_SHUTDOWN;
1323 kill(sp->se_process, SIGHUP);
1324 continue;
1325 }
1326 sp->se_flags &= ~SE_SHUTDOWN;
1327 old_getty = sp->se_getty ? strdup(sp->se_getty) : 0;
1328 old_window = sp->se_window ? strdup(sp->se_window) : 0;
1329 old_type = sp->se_type ? strdup(sp->se_type) : 0;
1330 if (setupargv(sp, typ) == 0) {
1331 warning("can't parse getty for port %s",
1332 sp->se_device);
1333 sp->se_flags |= SE_SHUTDOWN;
1334 kill(sp->se_process, SIGHUP);
1335 }
1336 else if ( !old_getty
1337 || (!old_type && sp->se_type)
1338 || (old_type && !sp->se_type)
1339 || (!old_window && sp->se_window)
1340 || (old_window && !sp->se_window)
1341 || (strcmp(old_getty, sp->se_getty) != 0)
1342 || (old_window && strcmp(old_window, sp->se_window) != 0)
1343 || (old_type && strcmp(old_type, sp->se_type) != 0)
1344 ) {
1345 /* Don't set SE_SHUTDOWN here */
1346 sp->se_nspace = 0;
1347 sp->se_started = 0;
1348 kill(sp->se_process, SIGHUP);
1349 }
1350 if (old_getty)
1351 free(old_getty);
1352 if (old_getty)
1353 free(old_window);
1354 if (old_type)
1355 free(old_type);
1356 continue;
1357 }
1358
1359 new_session(sprev, session_index, typ);
1360 }
1361
1362 endttyent();
1363
1364 return (state_func_t) multi_user;
1365}
1366
1367/*
1368 * Block further logins.
1369 */
1370state_func_t
1371catatonia()
1372{
1373 register session_t *sp;
1374
1375 for (sp = sessions; sp; sp = sp->se_next)
1376 sp->se_flags |= SE_SHUTDOWN;
1377
1378 return (state_func_t) multi_user;
1379}
1380
1381/*
1382 * Note SIGALRM.
1383 */
1384void
1385alrm_handler(sig)
1386 int sig;
1387{
1388 (void)sig;
1389 clang = 1;
1390}
1391
1392/*
1393 * Bring the system down to single user.
1394 */
1395state_func_t
1396death()
1397{
1398 register session_t *sp;
1399 register int i;
1400 pid_t pid;
1401 static const int death_sigs[2] = { SIGTERM, SIGKILL };
1402
1403 /* NB: should send a message to the session logger to avoid blocking. */
1404 logwtmp("~", "shutdown", "");
1405
1406 for (sp = sessions; sp; sp = sp->se_next) {
1407 sp->se_flags |= SE_SHUTDOWN;
1408 kill(sp->se_process, SIGHUP);
1409 }
1410
1411 /* Try to run the rc.shutdown script within a period of time */
1412 (void) runshutdown();
1413
1414 for (i = 0; i < 2; ++i) {
1415 if (kill(-1, death_sigs[i]) == -1 && errno == ESRCH)
1416 return (state_func_t) single_user;
1417
1418 clang = 0;
1419 alarm(DEATH_WATCH);
1420 do
1421 if ((pid = waitpid(-1, (int *)0, 0)) != -1)
1422 collect_child(pid);
1423 while (clang == 0 && errno != ECHILD);
1424
1425 if (errno == ECHILD)
1426 return (state_func_t) single_user;
1427 }
1428
1429 warning("some processes would not die; ps axl advised");
1430
1431 return (state_func_t) single_user;
1432}
1433
1434/*
1435 * Run the system shutdown script.
1436 *
1437 * Exit codes: XXX I should document more
1438 * -2 shutdown script terminated abnormally
1439 * -1 fatal error - can't run script
1440 * 0 good.
1441 * >0 some error (exit code)
1442 */
1443int
1444runshutdown()
1445{
1446 pid_t pid, wpid;
1447 int status;
1448 int shutdowntimeout;
1449 size_t len;
1450 char *argv[3];
1451 struct sigaction sa;
1452 struct stat sb;
1453
1454 /*
1455 * rc.shutdown is optional, so to prevent any unnecessary
1456 * complaints from the shell we simply don't run it if the
1457 * file does not exist. If the stat() here fails for other
1458 * reasons, we'll let the shell complain.
1459 */
1460 if (stat(_PATH_RUNDOWN, &sb) == -1 && errno == ENOENT)
1461 return 0;
1462
1463 if ((pid = fork()) == 0) {
1464 int fd;
1465
1466 /* Assume that init already grab console as ctty before */
1467
1468 sigemptyset(&sa.sa_mask);
1469 sa.sa_flags = 0;
1470 sa.sa_handler = SIG_IGN;
1471 (void) sigaction(SIGTSTP, &sa, (struct sigaction *)0);
1472 (void) sigaction(SIGHUP, &sa, (struct sigaction *)0);
1473
1474 if ((fd = open(_PATH_CONSOLE, O_RDWR)) == -1)
1475 warning("can't open %s: %m", _PATH_CONSOLE);
1476 else {
1477 (void) dup2(fd, 0);
1478 (void) dup2(fd, 1);
1479 (void) dup2(fd, 2);
1480 if (fd > 2)
1481 close(fd);
1482 }
1483
1484 /*
1485 * Run the shutdown script.
1486 */
1487 argv[0] = "sh";
1488 argv[1] = _PATH_RUNDOWN;
1489 argv[2] = 0;
1490
1491 sigprocmask(SIG_SETMASK, &sa.sa_mask, (sigset_t *) 0);
1492
1493#ifdef LOGIN_CAP
1494 setprocresources(RESOURCE_RC);
1495#endif
1496 execv(_PATH_BSHELL, argv);
1497 warning("can't exec %s for %s: %m", _PATH_BSHELL, _PATH_RUNDOWN);
1498 _exit(1); /* force single user mode */
1499 }
1500
1501 if (pid == -1) {
1502 emergency("can't fork for %s on %s: %m",
1503 _PATH_BSHELL, _PATH_RUNDOWN);
1504 while (waitpid(-1, (int *) 0, WNOHANG) > 0)
1505 continue;
1506 sleep(STALL_TIMEOUT);
1507 return -1;
1508 }
1509
1510 len = sizeof(shutdowntimeout);
1511 if (sysctlbyname("kern.shutdown_timeout",
1512 &shutdowntimeout,
1513 &len, NULL, 0) == -1 || shutdowntimeout < 2)
1514 shutdowntimeout = DEATH_SCRIPT;
1515 alarm(shutdowntimeout);
1516 clang = 0;
1517 /*
1518 * Copied from single_user(). This is a bit paranoid.
1519 * Use the same ALRM handler.
1520 */
1521 do {
1522 if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1)
1523 collect_child(wpid);
1524 if (clang == 1) {
1525 /* we were waiting for the sub-shell */
1526 kill(wpid, SIGTERM);
1527 warning("timeout expired for %s on %s: %m; going to single used mode",
1528 _PATH_BSHELL, _PATH_RUNDOWN);
1529 return -1;
1530 }
1531 if (wpid == -1) {
1532 if (errno == EINTR)
1533 continue;
1534 warning("wait for %s on %s failed: %m; going to single user mode",
1535 _PATH_BSHELL, _PATH_RUNDOWN);
1536 return -1;
1537 }
1538 if (wpid == pid && WIFSTOPPED(status)) {
1539 warning("init: %s on %s stopped, restarting\n",
1540 _PATH_BSHELL, _PATH_RUNDOWN);
1541 kill(pid, SIGCONT);
1542 wpid = -1;
1543 }
1544 } while (wpid != pid && !clang);
1545
1546 /* Turn off the alarm */
1547 alarm(0);
1548
1549 if (WIFSIGNALED(status) && WTERMSIG(status) == SIGTERM &&
1550 requested_transition == catatonia) {
1551 /*
1552 * /etc/rc.shutdown executed /sbin/reboot;
1553 * wait for the end quietly
1554 */
1555 sigset_t s;
1556
1557 sigfillset(&s);
1558 for (;;)
1559 sigsuspend(&s);
1560 }
1561
1562 if (!WIFEXITED(status)) {
1563 warning("%s on %s terminated abnormally, going to single user mode",
1564 _PATH_BSHELL, _PATH_RUNDOWN);
1565 return -2;
1566 }
1567
1568 if ((status = WEXITSTATUS(status)) != 0)
1569 warning("%s returned status %d", _PATH_RUNDOWN, status);
1570
1571 return status;
1572}
1573
1574char *
1575strk (char *p)
1576{
1577 static char *t;
1578 char *q;
1579 int c;
1580
1581 if (p)
1582 t = p;
1583 if (!t)
1584 return 0;
1585
1586 c = *t;
1587 while (c == ' ' || c == '\t' )
1588 c = *++t;
1589 if (!c) {
1590 t = 0;
1591 return 0;
1592 }
1593 q = t;
1594 if (c == '\'') {
1595 c = *++t;
1596 q = t;
1597 while (c && c != '\'')
1598 c = *++t;
1599 if (!c) /* unterminated string */
1600 q = t = 0;
1601 else
1602 *t++ = 0;
1603 } else {
1604 while (c && c != ' ' && c != '\t' )
1605 c = *++t;
1606 *t++ = 0;
1607 if (!c)
1608 t = 0;
1609 }
1610 return q;
1611}
1612
1613#ifdef LOGIN_CAP
1614void
1615setprocresources(cname)
1616 const char *cname;
1617{
1618 login_cap_t *lc;
1619 if ((lc = login_getclassbyname(cname, NULL)) != NULL) {
1620 setusercontext(lc, (struct passwd*)NULL, 0, LOGIN_SETPRIORITY|LOGIN_SETRESOURCES);
1621 login_close(lc);
1622 }
1623}
1624#endif
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