2569a54018565b514b169ebbde3228cc70fa0b53
[sysvinit.git] / src / init.c
1 /*
2 * Init A System-V Init Clone.
3 *
4 * Usage: /sbin/init
5 * init [0123456SsQqAaBbCc]
6 * telinit [0123456SsQqAaBbCc]
7 *
8 * Version: @(#)init.c 2.86 30-Jul-2004 miquels@cistron.nl
9 */
10 #define VERSION "2.89"
11 #define DATE "26-Mar-2010"
12 /*
13 * This file is part of the sysvinit suite,
14 * Copyright (C) 1991-2004 Miquel van Smoorenburg.
15 *
16 * This program is free software; you can redistribute it and/or modify
17 * it under the terms of the GNU General Public License as published by
18 * the Free Software Foundation; either version 2 of the License, or
19 * (at your option) any later version.
20 *
21 * This program is distributed in the hope that it will be useful,
22 * but WITHOUT ANY WARRANTY; without even the implied warranty of
23 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
24 * GNU General Public License for more details.
25 *
26 * You should have received a copy of the GNU General Public License
27 * along with this program; if not, write to the Free Software
28 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
29 *
30 */
31
32 #include <sys/types.h>
33 #include <sys/stat.h>
34 #include <sys/ioctl.h>
35 #include <sys/wait.h>
36 #ifdef __linux__
37 #include <sys/kd.h>
38 #endif
39 #include <sys/resource.h>
40 #include <stdlib.h>
41 #include <unistd.h>
42 #include <errno.h>
43 #include <stdio.h>
44 #include <time.h>
45 #include <fcntl.h>
46 #include <string.h>
47 #include <signal.h>
48 #include <termios.h>
49 #include <utmp.h>
50 #include <ctype.h>
51 #include <stdarg.h>
52 #include <sys/ttydefaults.h>
53 #include <sys/syslog.h>
54 #include <sys/time.h>
55
56 #ifdef WITH_SELINUX
57 # include <selinux/selinux.h>
58 #endif
59
60 #ifdef __i386__
61 # ifdef __GLIBC__
62 /* GNU libc 2.x */
63 # define STACK_DEBUG 1
64 # if (__GLIBC__ == 2 && __GLIBC_MINOR__ == 0)
65 /* Only glibc 2.0 needs this */
66 # include <sigcontext.h>
67 # elif ( __GLIBC__ > 2) && ((__GLIBC__ == 2) && (__GLIBC_MINOR__ >= 1))
68 # include <bits/sigcontext.h>
69 # endif
70 # endif
71 #endif
72
73 #include "init.h"
74 #include "initreq.h"
75 #include "paths.h"
76 #include "reboot.h"
77 #include "set.h"
78
79 #ifndef SIGPWR
80 # define SIGPWR SIGUSR2
81 #endif
82
83 #ifndef CBAUD
84 # define CBAUD 0
85 #endif
86 #ifndef CBAUDEX
87 # define CBAUDEX 0
88 #endif
89
90 /* Set a signal handler. */
91 #define SETSIG(sa, sig, fun, flags) \
92 do { \
93 memset(&sa, 0, sizeof(sa)); \
94 sa.sa_handler = fun; \
95 sa.sa_flags = flags; \
96 sigemptyset(&sa.sa_mask); \
97 sigaction(sig, &sa, NULL); \
98 } while(0)
99
100 /* Version information */
101 char *Version = "@(#) init " VERSION " " DATE " miquels@cistron.nl";
102 char *bootmsg = "version " VERSION " %s";
103 #define E_VERSION "INIT_VERSION=sysvinit-" VERSION
104
105 CHILD *family = NULL; /* The linked list of all entries */
106 CHILD *newFamily = NULL; /* The list after inittab re-read */
107
108 CHILD ch_emerg = { /* Emergency shell */
109 WAITING, 0, 0, 0, 0,
110 "~~",
111 "S",
112 3,
113 "/sbin/sulogin",
114 NULL,
115 NULL
116 };
117
118 char runlevel = 'S'; /* The current run level */
119 char thislevel = 'S'; /* The current runlevel */
120 char prevlevel = 'N'; /* Previous runlevel */
121 int dfl_level = 0; /* Default runlevel */
122 sig_atomic_t got_cont = 0; /* Set if we received the SIGCONT signal */
123 sig_atomic_t got_signals; /* Set if we received a signal. */
124 int emerg_shell = 0; /* Start emergency shell? */
125 int wrote_wtmp_reboot = 1; /* Set when we wrote the reboot record */
126 int wrote_utmp_reboot = 1; /* Set when we wrote the reboot record */
127 int wrote_wtmp_rlevel = 1; /* Set when we wrote the runlevel record */
128 int wrote_utmp_rlevel = 1; /* Set when we wrote the runlevel record */
129 int sltime = 5; /* Sleep time between TERM and KILL */
130 char *argv0; /* First arguments; show up in ps listing */
131 int maxproclen; /* Maximal length of argv[0] with \0 */
132 struct utmp utproto; /* Only used for sizeof(utproto.ut_id) */
133 char *console_dev; /* Console device. */
134 int pipe_fd = -1; /* /dev/initctl */
135 int did_boot = 0; /* Did we already do BOOT* stuff? */
136 int main(int, char **);
137
138 /* Used by re-exec part */
139 int reload = 0; /* Should we do initialization stuff? */
140 char *myname="/sbin/init"; /* What should we exec */
141 int oops_error; /* Used by some of the re-exec code. */
142 const char *Signature = "12567362"; /* Signature for re-exec fd */
143
144 /* Macro to see if this is a special action */
145 #define ISPOWER(i) ((i) == POWERWAIT || (i) == POWERFAIL || \
146 (i) == POWEROKWAIT || (i) == POWERFAILNOW || \
147 (i) == CTRLALTDEL)
148
149 /* ascii values for the `action' field. */
150 struct actions {
151 char *name;
152 int act;
153 } actions[] = {
154 { "respawn", RESPAWN },
155 { "wait", WAIT },
156 { "once", ONCE },
157 { "boot", BOOT },
158 { "bootwait", BOOTWAIT },
159 { "powerfail", POWERFAIL },
160 { "powerfailnow",POWERFAILNOW },
161 { "powerwait", POWERWAIT },
162 { "powerokwait", POWEROKWAIT },
163 { "ctrlaltdel", CTRLALTDEL },
164 { "off", OFF },
165 { "ondemand", ONDEMAND },
166 { "initdefault", INITDEFAULT },
167 { "sysinit", SYSINIT },
168 { "kbrequest", KBREQUEST },
169 { NULL, 0 },
170 };
171
172 /*
173 * State parser token table (see receive_state)
174 */
175 struct {
176 char name[4];
177 int cmd;
178 } cmds[] = {
179 { "VER", C_VER },
180 { "END", C_END },
181 { "REC", C_REC },
182 { "EOR", C_EOR },
183 { "LEV", C_LEV },
184 { "FL ", C_FLAG },
185 { "AC ", C_ACTION },
186 { "CMD", C_PROCESS },
187 { "PID", C_PID },
188 { "EXS", C_EXS },
189 { "-RL", D_RUNLEVEL },
190 { "-TL", D_THISLEVEL },
191 { "-PL", D_PREVLEVEL },
192 { "-SI", D_GOTSIGN },
193 { "-WR", D_WROTE_WTMP_REBOOT},
194 { "-WU", D_WROTE_UTMP_REBOOT},
195 { "-ST", D_SLTIME },
196 { "-DB", D_DIDBOOT },
197 { "-LW", D_WROTE_WTMP_RLEVEL},
198 { "-LU", D_WROTE_UTMP_RLEVEL},
199 { "", 0 }
200 };
201 struct {
202 char *name;
203 int mask;
204 } flags[]={
205 {"RU",RUNNING},
206 {"DE",DEMAND},
207 {"XD",XECUTED},
208 {"WT",WAITING},
209 {NULL,0}
210 };
211
212 #define NR_EXTRA_ENV 16
213 char *extra_env[NR_EXTRA_ENV];
214
215
216 /*
217 * Sleep a number of seconds.
218 *
219 * This only works correctly because the linux select updates
220 * the elapsed time in the struct timeval passed to select!
221 */
222 static
223 void do_sleep(int sec)
224 {
225 struct timeval tv;
226
227 tv.tv_sec = sec;
228 tv.tv_usec = 0;
229
230 while(select(0, NULL, NULL, NULL, &tv) < 0 && errno == EINTR)
231 ;
232 }
233
234
235 /*
236 * Non-failing allocation routines (init cannot fail).
237 */
238 static
239 void *imalloc(size_t size)
240 {
241 void *m;
242
243 while ((m = malloc(size)) == NULL) {
244 initlog(L_VB, "out of memory");
245 do_sleep(5);
246 }
247 memset(m, 0, size);
248 return m;
249 }
250
251 static
252 char *istrdup(const char *s)
253 {
254 char *m;
255 int l;
256
257 l = strlen(s) + 1;
258 m = imalloc(l);
259 memcpy(m, s, l);
260 return m;
261 }
262
263
264 /*
265 * Send the state info of the previous running init to
266 * the new one, in a version-independant way.
267 */
268 static
269 void send_state(int fd)
270 {
271 FILE *fp;
272 CHILD *p;
273 int i,val;
274
275 fp = fdopen(fd,"w");
276
277 fprintf(fp, "VER%s\n", Version);
278 fprintf(fp, "-RL%c\n", runlevel);
279 fprintf(fp, "-TL%c\n", thislevel);
280 fprintf(fp, "-PL%c\n", prevlevel);
281 fprintf(fp, "-SI%u\n", got_signals);
282 fprintf(fp, "-WR%d\n", wrote_wtmp_reboot);
283 fprintf(fp, "-WU%d\n", wrote_utmp_reboot);
284 fprintf(fp, "-ST%d\n", sltime);
285 fprintf(fp, "-DB%d\n", did_boot);
286
287 for (p = family; p; p = p->next) {
288 fprintf(fp, "REC%s\n", p->id);
289 fprintf(fp, "LEV%s\n", p->rlevel);
290 for (i = 0, val = p->flags; flags[i].mask; i++)
291 if (val & flags[i].mask) {
292 val &= ~flags[i].mask;
293 fprintf(fp, "FL %s\n",flags[i].name);
294 }
295 fprintf(fp, "PID%d\n",p->pid);
296 fprintf(fp, "EXS%u\n",p->exstat);
297 for(i = 0; actions[i].act; i++)
298 if (actions[i].act == p->action) {
299 fprintf(fp, "AC %s\n", actions[i].name);
300 break;
301 }
302 fprintf(fp, "CMD%s\n", p->process);
303 fprintf(fp, "EOR\n");
304 }
305 fprintf(fp, "END\n");
306 fclose(fp);
307 }
308
309 /*
310 * Read a string from a file descriptor.
311 * FIXME: why not use fgets() ?
312 */
313 static int get_string(char *p, int size, FILE *f)
314 {
315 int c;
316
317 while ((c = getc(f)) != EOF && c != '\n') {
318 if (--size > 0)
319 *p++ = c;
320 }
321 *p = '\0';
322 return (c != EOF) && (size > 0);
323 }
324
325 /*
326 * Read trailing data from the state pipe until we see a newline.
327 */
328 static int get_void(FILE *f)
329 {
330 int c;
331
332 while ((c = getc(f)) != EOF && c != '\n')
333 ;
334
335 return (c != EOF);
336 }
337
338 /*
339 * Read the next "command" from the state pipe.
340 */
341 static int get_cmd(FILE *f)
342 {
343 char cmd[4] = " ";
344 int i;
345
346 if (fread(cmd, 1, sizeof(cmd) - 1, f) != sizeof(cmd) - 1)
347 return C_EOF;
348
349 for(i = 0; cmds[i].cmd && strcmp(cmds[i].name, cmd) != 0; i++)
350 ;
351 return cmds[i].cmd;
352 }
353
354 /*
355 * Read a CHILD * from the state pipe.
356 */
357 static CHILD *get_record(FILE *f)
358 {
359 int cmd;
360 char s[32];
361 int i;
362 CHILD *p;
363
364 do {
365 switch (cmd = get_cmd(f)) {
366 case C_END:
367 get_void(f);
368 return NULL;
369 case 0:
370 get_void(f);
371 break;
372 case C_REC:
373 break;
374 case D_RUNLEVEL:
375 fscanf(f, "%c\n", &runlevel);
376 break;
377 case D_THISLEVEL:
378 fscanf(f, "%c\n", &thislevel);
379 break;
380 case D_PREVLEVEL:
381 fscanf(f, "%c\n", &prevlevel);
382 break;
383 case D_GOTSIGN:
384 fscanf(f, "%u\n", &got_signals);
385 break;
386 case D_WROTE_WTMP_REBOOT:
387 fscanf(f, "%d\n", &wrote_wtmp_reboot);
388 break;
389 case D_WROTE_UTMP_REBOOT:
390 fscanf(f, "%d\n", &wrote_utmp_reboot);
391 break;
392 case D_SLTIME:
393 fscanf(f, "%d\n", &sltime);
394 break;
395 case D_DIDBOOT:
396 fscanf(f, "%d\n", &did_boot);
397 break;
398 case D_WROTE_WTMP_RLEVEL:
399 fscanf(f, "%d\n", &wrote_wtmp_rlevel);
400 break;
401 case D_WROTE_UTMP_RLEVEL:
402 fscanf(f, "%d\n", &wrote_utmp_rlevel);
403 break;
404 default:
405 if (cmd > 0 || cmd == C_EOF) {
406 oops_error = -1;
407 return NULL;
408 }
409 }
410 } while (cmd != C_REC);
411
412 p = imalloc(sizeof(CHILD));
413 get_string(p->id, sizeof(p->id), f);
414
415 do switch(cmd = get_cmd(f)) {
416 case 0:
417 case C_EOR:
418 get_void(f);
419 break;
420 case C_PID:
421 fscanf(f, "%d\n", &(p->pid));
422 break;
423 case C_EXS:
424 fscanf(f, "%u\n", &(p->exstat));
425 break;
426 case C_LEV:
427 get_string(p->rlevel, sizeof(p->rlevel), f);
428 break;
429 case C_PROCESS:
430 get_string(p->process, sizeof(p->process), f);
431 break;
432 case C_FLAG:
433 get_string(s, sizeof(s), f);
434 for(i = 0; flags[i].name; i++) {
435 if (strcmp(flags[i].name,s) == 0)
436 break;
437 }
438 p->flags |= flags[i].mask;
439 break;
440 case C_ACTION:
441 get_string(s, sizeof(s), f);
442 for(i = 0; actions[i].name; i++) {
443 if (strcmp(actions[i].name, s) == 0)
444 break;
445 }
446 p->action = actions[i].act ? actions[i].act : OFF;
447 break;
448 default:
449 free(p);
450 oops_error = -1;
451 return NULL;
452 } while( cmd != C_EOR);
453
454 return p;
455 }
456
457 /*
458 * Read the complete state info from the state pipe.
459 * Returns 0 on success
460 */
461 static
462 int receive_state(int fd)
463 {
464 FILE *f;
465 char old_version[256];
466 CHILD **pp;
467
468 f = fdopen(fd, "r");
469
470 if (get_cmd(f) != C_VER) {
471 fclose(f);
472 return -1;
473 }
474 get_string(old_version, sizeof(old_version), f);
475 oops_error = 0;
476 for (pp = &family; (*pp = get_record(f)) != NULL; pp = &((*pp)->next))
477 ;
478 fclose(f);
479 return oops_error;
480 }
481
482 /*
483 * Set the process title.
484 */
485 #ifdef __GNUC__
486 __attribute__ ((format (printf, 1, 2)))
487 #endif
488 static int setproctitle(char *fmt, ...)
489 {
490 va_list ap;
491 int len;
492 char buf[256];
493
494 buf[0] = 0;
495
496 va_start(ap, fmt);
497 len = vsnprintf(buf, sizeof(buf), fmt, ap);
498 va_end(ap);
499
500 if (maxproclen > 1) {
501 memset(argv0, 0, maxproclen);
502 strncpy(argv0, buf, maxproclen - 1);
503 }
504
505 return len;
506 }
507
508 /*
509 * Set console_dev to a working console.
510 */
511 static
512 void console_init(void)
513 {
514 int fd;
515 int tried_devcons = 0;
516 int tried_vtmaster = 0;
517 char *s;
518
519 if ((s = getenv("CONSOLE")) != NULL)
520 console_dev = s;
521 else {
522 console_dev = CONSOLE;
523 tried_devcons++;
524 }
525
526 while ((fd = open(console_dev, O_RDONLY|O_NONBLOCK)) < 0) {
527 if (!tried_devcons) {
528 tried_devcons++;
529 console_dev = CONSOLE;
530 continue;
531 }
532 if (!tried_vtmaster) {
533 tried_vtmaster++;
534 console_dev = VT_MASTER;
535 continue;
536 }
537 break;
538 }
539 if (fd < 0)
540 console_dev = "/dev/null";
541 else
542 close(fd);
543 }
544
545
546 /*
547 * Open the console with retries.
548 */
549 static
550 int console_open(int mode)
551 {
552 int f, fd = -1;
553 int m;
554
555 /*
556 * Open device in nonblocking mode.
557 */
558 m = mode | O_NONBLOCK;
559
560 /*
561 * Retry the open five times.
562 */
563 for(f = 0; f < 5; f++) {
564 if ((fd = open(console_dev, m)) >= 0) break;
565 usleep(10000);
566 }
567
568 if (fd < 0) return fd;
569
570 /*
571 * Set original flags.
572 */
573 if (m != mode)
574 fcntl(fd, F_SETFL, mode);
575 return fd;
576 }
577
578 /*
579 * We got a signal (HUP PWR WINCH ALRM INT)
580 */
581 static
582 void signal_handler(int sig)
583 {
584 ADDSET(got_signals, sig);
585 }
586
587 /*
588 * SIGCHLD: one of our children has died.
589 */
590 static
591 # ifdef __GNUC__
592 void chld_handler(int sig __attribute__((unused)))
593 # else
594 void chld_handler(int sig)
595 # endif
596 {
597 CHILD *ch;
598 int pid, st;
599 int saved_errno = errno;
600
601 /*
602 * Find out which process(es) this was (were)
603 */
604 while((pid = waitpid(-1, &st, WNOHANG)) != 0) {
605 if (errno == ECHILD) break;
606 for( ch = family; ch; ch = ch->next )
607 if ( ch->pid == pid && (ch->flags & RUNNING) ) {
608 INITDBG(L_VB,
609 "chld_handler: marked %d as zombie",
610 ch->pid);
611 ADDSET(got_signals, SIGCHLD);
612 ch->exstat = st;
613 ch->flags |= ZOMBIE;
614 if (ch->new) {
615 ch->new->exstat = st;
616 ch->new->flags |= ZOMBIE;
617 }
618 break;
619 }
620 if (ch == NULL) {
621 INITDBG(L_VB, "chld_handler: unknown child %d exited.",
622 pid);
623 }
624 }
625 errno = saved_errno;
626 }
627
628 /*
629 * Linux ignores all signals sent to init when the
630 * SIG_DFL handler is installed. Therefore we must catch SIGTSTP
631 * and SIGCONT, or else they won't work....
632 *
633 * The SIGCONT handler
634 */
635 static
636 # ifdef __GNUC__
637 void cont_handler(int sig __attribute__((unused)))
638 # else
639 void cont_handler(int sig)
640 # endif
641 {
642 got_cont = 1;
643 }
644
645 /*
646 * Fork and dump core in /.
647 */
648 static
649 void coredump(void)
650 {
651 static int dumped = 0;
652 struct rlimit rlim;
653 sigset_t mask;
654
655 if (dumped) return;
656 dumped = 1;
657
658 if (fork() != 0) return;
659
660 sigfillset(&mask);
661 sigprocmask(SIG_SETMASK, &mask, NULL);
662
663 rlim.rlim_cur = RLIM_INFINITY;
664 rlim.rlim_max = RLIM_INFINITY;
665 setrlimit(RLIMIT_CORE, &rlim);
666 chdir("/");
667
668 signal(SIGSEGV, SIG_DFL);
669 raise(SIGSEGV);
670 sigdelset(&mask, SIGSEGV);
671 sigprocmask(SIG_SETMASK, &mask, NULL);
672
673 do_sleep(5);
674 exit(0);
675 }
676
677 /*
678 * OOPS: segmentation violation!
679 * If we have the info, print where it occured.
680 * Then sleep 30 seconds and try to continue.
681 */
682 static
683 #if defined(STACK_DEBUG) && defined(__linux__)
684 # ifdef __GNUC__
685 void segv_handler(int sig __attribute__((unused)), struct sigcontext ctx)
686 # else
687 void segv_handler(int sig, struct sigcontext ctx)
688 # endif
689 {
690 char *p = "";
691 int saved_errno = errno;
692
693 if ((void *)ctx.eip >= (void *)do_sleep &&
694 (void *)ctx.eip < (void *)main)
695 p = " (code)";
696 initlog(L_VB, "PANIC: segmentation violation at %p%s! "
697 "sleeping for 30 seconds.", (void *)ctx.eip, p);
698 coredump();
699 do_sleep(30);
700 errno = saved_errno;
701 }
702 #else
703 # ifdef __GNUC__
704 void segv_handler(int sig __attribute__((unused)))
705 # else
706 void segv_handler(int sig)
707 # endif
708 {
709 int saved_errno = errno;
710
711 initlog(L_VB,
712 "PANIC: segmentation violation! sleeping for 30 seconds.");
713 coredump();
714 do_sleep(30);
715 errno = saved_errno;
716 }
717 #endif
718
719 /*
720 * The SIGSTOP & SIGTSTP handler
721 */
722 static
723 # ifdef __GNUC__
724 void stop_handler(int sig __attribute__((unused)))
725 # else
726 void stop_handler(int sig)
727 # endif
728 {
729 int saved_errno = errno;
730
731 got_cont = 0;
732 while(!got_cont) pause();
733 got_cont = 0;
734 errno = saved_errno;
735 }
736
737 /*
738 * Set terminal settings to reasonable defaults
739 */
740 static
741 void console_stty(void)
742 {
743 struct termios tty;
744 int fd;
745
746 if ((fd = console_open(O_RDWR|O_NOCTTY)) < 0) {
747 initlog(L_VB, "can't open %s", console_dev);
748 return;
749 }
750
751 #ifdef __FreeBSD_kernel__
752 /*
753 * The kernel of FreeBSD expects userland to set TERM. Usually, we want
754 * "cons25". Later, gettys might disagree on this (i.e. we're not using
755 * syscons) but some boot scripts, like /etc/init.d/xserver-xorg, still
756 * need a non-dumb terminal.
757 */
758 putenv ("TERM=cons25");
759 #endif
760
761 (void) tcgetattr(fd, &tty);
762
763 tty.c_cflag &= CBAUD|CBAUDEX|CSIZE|CSTOPB|PARENB|PARODD;
764 tty.c_cflag |= HUPCL|CLOCAL|CREAD;
765
766 tty.c_cc[VINTR] = CINTR;
767 tty.c_cc[VQUIT] = CQUIT;
768 tty.c_cc[VERASE] = CERASE; /* ASCII DEL (0177) */
769 tty.c_cc[VKILL] = CKILL;
770 tty.c_cc[VEOF] = CEOF;
771 tty.c_cc[VTIME] = 0;
772 tty.c_cc[VMIN] = 1;
773 #ifdef VSWTC /* not defined on FreeBSD */
774 tty.c_cc[VSWTC] = _POSIX_VDISABLE;
775 #endif /* VSWTC */
776 tty.c_cc[VSTART] = CSTART;
777 tty.c_cc[VSTOP] = CSTOP;
778 tty.c_cc[VSUSP] = CSUSP;
779 tty.c_cc[VEOL] = _POSIX_VDISABLE;
780 tty.c_cc[VREPRINT] = CREPRINT;
781 tty.c_cc[VDISCARD] = CDISCARD;
782 tty.c_cc[VWERASE] = CWERASE;
783 tty.c_cc[VLNEXT] = CLNEXT;
784 tty.c_cc[VEOL2] = _POSIX_VDISABLE;
785
786 /*
787 * Set pre and post processing
788 */
789 tty.c_iflag = IGNPAR|ICRNL|IXON|IXANY
790 #ifdef IUTF8 /* Not defined on FreeBSD */
791 | (tty.c_iflag & IUTF8)
792 #endif /* IUTF8 */
793 ;
794 tty.c_oflag = OPOST|ONLCR;
795 tty.c_lflag = ISIG|ICANON|ECHO|ECHOCTL|ECHOPRT|ECHOKE;
796
797 #if defined(SANE_TIO) && (SANE_TIO == 1)
798 /*
799 * Disable flow control (-ixon), ignore break (ignbrk),
800 * and make nl/cr more usable (sane).
801 */
802 tty.c_iflag |= IGNBRK;
803 tty.c_iflag &= ~(BRKINT|INLCR|IGNCR|IXON);
804 tty.c_oflag &= ~(OCRNL|ONLRET);
805 #endif
806 /*
807 * Now set the terminal line.
808 * We don't care about non-transmitted output data
809 * and non-read input data.
810 */
811 (void) tcsetattr(fd, TCSANOW, &tty);
812 (void) tcflush(fd, TCIOFLUSH);
813 (void) close(fd);
814 }
815
816 static ssize_t
817 safe_write(int fd, const char *buffer, size_t count)
818 {
819 ssize_t offset = 0;
820
821 while (count > 0) {
822 ssize_t block = write(fd, &buffer[offset], count);
823
824 if (block < 0 && errno == EINTR)
825 continue;
826 if (block <= 0)
827 return offset ? offset : block;
828 offset += block;
829 count -= block;
830 }
831 return offset;
832 }
833
834 /*
835 * Print to the system console
836 */
837 void print(char *s)
838 {
839 int fd;
840
841 if ((fd = console_open(O_WRONLY|O_NOCTTY|O_NDELAY)) >= 0) {
842 safe_write(fd, s, strlen(s));
843 close(fd);
844 }
845 }
846
847 /*
848 * Log something to a logfile and the console.
849 */
850 #ifdef __GNUC__
851 __attribute__ ((format (printf, 2, 3)))
852 #endif
853 void initlog(int loglevel, char *s, ...)
854 {
855 va_list va_alist;
856 char buf[256];
857 sigset_t nmask, omask;
858
859 va_start(va_alist, s);
860 vsnprintf(buf, sizeof(buf), s, va_alist);
861 va_end(va_alist);
862
863 if (loglevel & L_SY) {
864 /*
865 * Re-establish connection with syslogd every time.
866 * Block signals while talking to syslog.
867 */
868 sigfillset(&nmask);
869 sigprocmask(SIG_BLOCK, &nmask, &omask);
870 openlog("init", 0, LOG_DAEMON);
871 syslog(LOG_INFO, "%s", buf);
872 closelog();
873 sigprocmask(SIG_SETMASK, &omask, NULL);
874 }
875
876 /*
877 * And log to the console.
878 */
879 if (loglevel & L_CO) {
880 print("\rINIT: ");
881 print(buf);
882 print("\r\n");
883 }
884 }
885
886 /*
887 * Add or replace specific environment value
888 */
889 int addnewenv(const char *new, char **curr, int n)
890 {
891 size_t nlen = strcspn(new, "=");
892 int i;
893 for (i = 0; i < n; i++) {
894 if (nlen != strcspn(curr[i], "="))
895 continue;
896 if (strncmp (new, curr[i], nlen) == 0)
897 break;
898 }
899 if (i >= n)
900 curr[n++] = istrdup(new);
901 else {
902 free(curr[i]);
903 curr[i] = istrdup(new);
904 }
905 return n;
906 }
907
908 /*
909 * Build a new environment for execve().
910 */
911 char **init_buildenv(int child)
912 {
913 char i_lvl[] = "RUNLEVEL=x";
914 char i_prev[] = "PREVLEVEL=x";
915 char i_cons[128];
916 char i_shell[] = "SHELL=" SHELL;
917 char **e;
918 int n, i;
919
920 for (n = 0; environ[n]; n++)
921 ;
922 n += NR_EXTRA_ENV + 1; /* Also room for last NULL */
923 if (child)
924 n += 8;
925
926 while ((e = (char**)calloc(n, sizeof(char *))) == NULL) {
927 initlog(L_VB, "out of memory");
928 do_sleep(5);
929 }
930
931 for (n = 0; environ[n]; n++)
932 e[n] = istrdup(environ[n]);
933
934 for (i = 0; i < NR_EXTRA_ENV; i++) {
935 if (extra_env[i] == NULL || *extra_env[i] == '\0')
936 continue;
937 n = addnewenv(extra_env[i], e, n);
938 }
939
940 if (child) {
941 snprintf(i_cons, sizeof(i_cons), "CONSOLE=%s", console_dev);
942 i_lvl[9] = thislevel;
943 i_prev[10] = prevlevel;
944 n = addnewenv(i_shell, e, n);
945 n = addnewenv(i_lvl, e, n);
946 n = addnewenv(i_prev, e, n);
947 n = addnewenv(i_cons, e, n);
948 n = addnewenv(E_VERSION, e, n);
949 }
950
951 e[n++] = NULL;
952
953 return e;
954 }
955
956
957 void init_freeenv(char **e)
958 {
959 int n;
960
961 for (n = 0; e[n]; n++)
962 free(e[n]);
963 free(e);
964 }
965
966
967 /*
968 * Fork and execute.
969 *
970 * This function is too long and indents too deep.
971 *
972 */
973 static
974 pid_t spawn(CHILD *ch, int *res)
975 {
976 char *args[16]; /* Argv array */
977 char buf[136]; /* Line buffer */
978 int f, st; /* Scratch variables */
979 char *ptr; /* Ditto */
980 time_t t; /* System time */
981 int oldAlarm; /* Previous alarm value */
982 char *proc = ch->process; /* Command line */
983 pid_t pid, pgrp; /* child, console process group. */
984 sigset_t nmask, omask; /* For blocking SIGCHLD */
985 struct sigaction sa;
986
987 *res = -1;
988 buf[sizeof(buf) - 1] = 0;
989
990 /* Skip '+' if it's there */
991 if (proc[0] == '+') proc++;
992
993 ch->flags |= XECUTED;
994
995 if (ch->action == RESPAWN || ch->action == ONDEMAND) {
996 /* Is the date stamp from less than 2 minutes ago? */
997 time(&t);
998 if (ch->tm + TESTTIME > t) {
999 ch->count++;
1000 } else {
1001 ch->count = 0;
1002 ch->tm = t;
1003 }
1004
1005 /* Do we try to respawn too fast? */
1006 if (ch->count >= MAXSPAWN) {
1007
1008 initlog(L_VB,
1009 "Id \"%s\" respawning too fast: disabled for %d minutes",
1010 ch->id, SLEEPTIME / 60);
1011 ch->flags &= ~RUNNING;
1012 ch->flags |= FAILING;
1013
1014 /* Remember the time we stopped */
1015 ch->tm = t;
1016
1017 /* Try again in 5 minutes */
1018 oldAlarm = alarm(0);
1019 if (oldAlarm > SLEEPTIME || oldAlarm <= 0) oldAlarm = SLEEPTIME;
1020 alarm(oldAlarm);
1021 return(-1);
1022 }
1023 }
1024
1025 /* See if there is an "initscript" (except in single user mode). */
1026 if (access(INITSCRIPT, R_OK) == 0 && runlevel != 'S') {
1027 /* Build command line using "initscript" */
1028 args[1] = SHELL;
1029 args[2] = INITSCRIPT;
1030 args[3] = ch->id;
1031 args[4] = ch->rlevel;
1032 args[5] = "unknown";
1033 for(f = 0; actions[f].name; f++) {
1034 if (ch->action == actions[f].act) {
1035 args[5] = actions[f].name;
1036 break;
1037 }
1038 }
1039 args[6] = proc;
1040 args[7] = NULL;
1041 } else if (strpbrk(proc, "~`!$^&*()=|\\{}[];\"'<>?")) {
1042 /* See if we need to fire off a shell for this command */
1043 /* Give command line to shell */
1044 args[1] = SHELL;
1045 args[2] = "-c";
1046 strcpy(buf, "exec ");
1047 strncat(buf, proc, sizeof(buf) - strlen(buf) - 1);
1048 args[3] = buf;
1049 args[4] = NULL;
1050 } else {
1051 /* Split up command line arguments */
1052 buf[0] = 0;
1053 strncat(buf, proc, sizeof(buf) - 1);
1054 ptr = buf;
1055 for(f = 1; f < 15; f++) {
1056 /* Skip white space */
1057 while(*ptr == ' ' || *ptr == '\t') ptr++;
1058 args[f] = ptr;
1059
1060 /* May be trailing space.. */
1061 if (*ptr == 0) break;
1062
1063 /* Skip this `word' */
1064 while(*ptr && *ptr != ' ' && *ptr != '\t' && *ptr != '#')
1065 ptr++;
1066
1067 /* If end-of-line, break */
1068 if (*ptr == '#' || *ptr == 0) {
1069 f++;
1070 *ptr = 0;
1071 break;
1072 }
1073 /* End word with \0 and continue */
1074 *ptr++ = 0;
1075 }
1076 args[f] = NULL;
1077 }
1078 args[0] = args[1];
1079 while(1) {
1080 /*
1081 * Block sigchild while forking.
1082 */
1083 sigemptyset(&nmask);
1084 sigaddset(&nmask, SIGCHLD);
1085 sigprocmask(SIG_BLOCK, &nmask, &omask);
1086
1087 if ((pid = fork()) == 0) {
1088
1089 close(0);
1090 close(1);
1091 close(2);
1092 if (pipe_fd >= 0) close(pipe_fd);
1093
1094 sigprocmask(SIG_SETMASK, &omask, NULL);
1095
1096 /*
1097 * In sysinit, boot, bootwait or single user mode:
1098 * for any wait-type subprocess we _force_ the console
1099 * to be its controlling tty.
1100 */
1101 if (strchr("*#sS", runlevel) && ch->flags & WAITING) {
1102 /*
1103 * We fork once extra. This is so that we can
1104 * wait and change the process group and session
1105 * of the console after exit of the leader.
1106 */
1107 setsid();
1108 if ((f = console_open(O_RDWR|O_NOCTTY)) >= 0) {
1109 /* Take over controlling tty by force */
1110 (void)ioctl(f, TIOCSCTTY, 1);
1111 dup(f);
1112 dup(f);
1113 }
1114
1115 /*
1116 * 4 Sep 2001, Andrea Arcangeli:
1117 * Fix a race in spawn() that is used to deadlock init in a
1118 * waitpid() loop: must set the childhandler as default before forking
1119 * off the child or the chld_handler could run before the waitpid loop
1120 * has a chance to find its zombie-child.
1121 */
1122 SETSIG(sa, SIGCHLD, SIG_DFL, SA_RESTART);
1123 if ((pid = fork()) < 0) {
1124 initlog(L_VB, "cannot fork: %s",
1125 strerror(errno));
1126 exit(1);
1127 }
1128 if (pid > 0) {
1129 pid_t rc;
1130 /*
1131 * Ignore keyboard signals etc.
1132 * Then wait for child to exit.
1133 */
1134 SETSIG(sa, SIGINT, SIG_IGN, SA_RESTART);
1135 SETSIG(sa, SIGTSTP, SIG_IGN, SA_RESTART);
1136 SETSIG(sa, SIGQUIT, SIG_IGN, SA_RESTART);
1137
1138 while ((rc = waitpid(pid, &st, 0)) != pid)
1139 if (rc < 0 && errno == ECHILD)
1140 break;
1141
1142 /*
1143 * Small optimization. See if stealing
1144 * controlling tty back is needed.
1145 */
1146 pgrp = tcgetpgrp(f);
1147 if (pgrp != getpid())
1148 exit(0);
1149
1150 /*
1151 * Steal controlling tty away. We do
1152 * this with a temporary process.
1153 */
1154 if ((pid = fork()) < 0) {
1155 initlog(L_VB, "cannot fork: %s",
1156 strerror(errno));
1157 exit(1);
1158 }
1159 if (pid == 0) {
1160 setsid();
1161 (void)ioctl(f, TIOCSCTTY, 1);
1162 exit(0);
1163 }
1164 while((rc = waitpid(pid, &st, 0)) != pid)
1165 if (rc < 0 && errno == ECHILD)
1166 break;
1167 exit(0);
1168 }
1169
1170 /* Set ioctl settings to default ones */
1171 console_stty();
1172
1173 } else { /* parent */
1174 int fd;
1175 setsid();
1176 if ((fd = console_open(O_RDWR|O_NOCTTY)) < 0) {
1177 initlog(L_VB, "open(%s): %s", console_dev,
1178 strerror(errno));
1179 fd = open("/dev/null", O_RDWR);
1180 }
1181 dup(fd);
1182 dup(fd);
1183 }
1184
1185 /*
1186 * Update utmp/wtmp file prior to starting
1187 * any child. This MUST be done right here in
1188 * the child process in order to prevent a race
1189 * condition that occurs when the child
1190 * process' time slice executes before the
1191 * parent (can and does happen in a uniprocessor
1192 * environment). If the child is a getty and
1193 * the race condition happens, then init's utmp
1194 * update will happen AFTER the getty runs
1195 * and expects utmp to be updated already!
1196 *
1197 * Do NOT log if process field starts with '+'
1198 * FIXME: that's for compatibility with *very*
1199 * old getties - probably it can be taken out.
1200 */
1201 if (ch->process[0] != '+')
1202 write_utmp_wtmp("", ch->id, getpid(), INIT_PROCESS, "");
1203
1204 /* Reset all the signals, set up environment */
1205 for(f = 1; f < NSIG; f++) SETSIG(sa, f, SIG_DFL, SA_RESTART);
1206 environ = init_buildenv(1);
1207
1208 /*
1209 * Execute prog. In case of ENOEXEC try again
1210 * as a shell script.
1211 */
1212 execvp(args[1], args + 1);
1213 if (errno == ENOEXEC) {
1214 args[1] = SHELL;
1215 args[2] = "-c";
1216 strcpy(buf, "exec ");
1217 strncat(buf, proc, sizeof(buf) - strlen(buf) - 1);
1218 args[3] = buf;
1219 args[4] = NULL;
1220 execvp(args[1], args + 1);
1221 }
1222 initlog(L_VB, "cannot execute \"%s\"", args[1]);
1223
1224 if (ch->process[0] != '+')
1225 write_utmp_wtmp("", ch->id, getpid(), DEAD_PROCESS, NULL);
1226 exit(1);
1227 }
1228 *res = pid;
1229 sigprocmask(SIG_SETMASK, &omask, NULL);
1230
1231 INITDBG(L_VB, "Started id %s (pid %d)", ch->id, pid);
1232
1233 if (pid == -1) {
1234 initlog(L_VB, "cannot fork, retry..");
1235 do_sleep(5);
1236 continue;
1237 }
1238 return(pid);
1239 }
1240 }
1241
1242 /*
1243 * Start a child running!
1244 */
1245 static
1246 void startup(CHILD *ch)
1247 {
1248 /*
1249 * See if it's disabled
1250 */
1251 if (ch->flags & FAILING) return;
1252
1253 switch(ch->action) {
1254
1255 case SYSINIT:
1256 case BOOTWAIT:
1257 case WAIT:
1258 case POWERWAIT:
1259 case POWERFAILNOW:
1260 case POWEROKWAIT:
1261 case CTRLALTDEL:
1262 if (!(ch->flags & XECUTED)) ch->flags |= WAITING;
1263 /* Fall through */
1264 case KBREQUEST:
1265 case BOOT:
1266 case POWERFAIL:
1267 case ONCE:
1268 if (ch->flags & XECUTED) break;
1269 case ONDEMAND:
1270 case RESPAWN:
1271 ch->flags |= RUNNING;
1272 (void)spawn(ch, &(ch->pid));
1273 break;
1274 }
1275 }
1276
1277
1278 /*
1279 * Read the inittab file.
1280 */
1281 static
1282 void read_inittab(void)
1283 {
1284 FILE *fp; /* The INITTAB file */
1285 CHILD *ch, *old, *i; /* Pointers to CHILD structure */
1286 CHILD *head = NULL; /* Head of linked list */
1287 #ifdef INITLVL
1288 struct stat st; /* To stat INITLVL */
1289 #endif
1290 sigset_t nmask, omask; /* For blocking SIGCHLD. */
1291 char buf[256]; /* Line buffer */
1292 char err[64]; /* Error message. */
1293 char *id, *rlevel,
1294 *action, *process; /* Fields of a line */
1295 char *p;
1296 int lineNo = 0; /* Line number in INITTAB file */
1297 int actionNo; /* Decoded action field */
1298 int f; /* Counter */
1299 int round; /* round 0 for SIGTERM, 1 for SIGKILL */
1300 int foundOne = 0; /* No killing no sleep */
1301 int talk; /* Talk to the user */
1302 int done = 0; /* Ready yet? */
1303
1304 #if DEBUG
1305 if (newFamily != NULL) {
1306 INITDBG(L_VB, "PANIC newFamily != NULL");
1307 exit(1);
1308 }
1309 INITDBG(L_VB, "Reading inittab");
1310 #endif
1311
1312 /*
1313 * Open INITTAB and read line by line.
1314 */
1315 if ((fp = fopen(INITTAB, "r")) == NULL)
1316 initlog(L_VB, "No inittab file found");
1317
1318 while(!done) {
1319 /*
1320 * Add single user shell entry at the end.
1321 */
1322 if (fp == NULL || fgets(buf, sizeof(buf), fp) == NULL) {
1323 done = 1;
1324 /*
1325 * See if we have a single user entry.
1326 */
1327 for(old = newFamily; old; old = old->next)
1328 if (strpbrk(old->rlevel, "S")) break;
1329 if (old == NULL)
1330 snprintf(buf, sizeof(buf), "~~:S:wait:%s\n", SULOGIN);
1331 else
1332 continue;
1333 }
1334 lineNo++;
1335 /*
1336 * Skip comments and empty lines
1337 */
1338 for(p = buf; *p == ' ' || *p == '\t'; p++)
1339 ;
1340 if (*p == '#' || *p == '\n') continue;
1341
1342 /*
1343 * Decode the fields
1344 */
1345 id = strsep(&p, ":");
1346 rlevel = strsep(&p, ":");
1347 action = strsep(&p, ":");
1348 process = strsep(&p, "\n");
1349
1350 /*
1351 * Check if syntax is OK. Be very verbose here, to
1352 * avoid newbie postings on comp.os.linux.setup :)
1353 */
1354 err[0] = 0;
1355 if (!id || !*id) strcpy(err, "missing id field");
1356 if (!rlevel) strcpy(err, "missing runlevel field");
1357 if (!process) strcpy(err, "missing process field");
1358 if (!action || !*action)
1359 strcpy(err, "missing action field");
1360 if (id && strlen(id) > sizeof(utproto.ut_id))
1361 sprintf(err, "id field too long (max %d characters)",
1362 (int)sizeof(utproto.ut_id));
1363 if (rlevel && strlen(rlevel) > 11)
1364 strcpy(err, "rlevel field too long (max 11 characters)");
1365 if (process && strlen(process) > 127)
1366 strcpy(err, "process field too long");
1367 if (action && strlen(action) > 32)
1368 strcpy(err, "action field too long");
1369 if (err[0] != 0) {
1370 initlog(L_VB, "%s[%d]: %s", INITTAB, lineNo, err);
1371 INITDBG(L_VB, "%s:%s:%s:%s", id, rlevel, action, process);
1372 continue;
1373 }
1374
1375 /*
1376 * Decode the "action" field
1377 */
1378 actionNo = -1;
1379 for(f = 0; actions[f].name; f++)
1380 if (strcasecmp(action, actions[f].name) == 0) {
1381 actionNo = actions[f].act;
1382 break;
1383 }
1384 if (actionNo == -1) {
1385 initlog(L_VB, "%s[%d]: %s: unknown action field",
1386 INITTAB, lineNo, action);
1387 continue;
1388 }
1389
1390 /*
1391 * See if the id field is unique
1392 */
1393 for(old = newFamily; old; old = old->next) {
1394 if(strcmp(old->id, id) == 0 && strcmp(id, "~~")) {
1395 initlog(L_VB, "%s[%d]: duplicate ID field \"%s\"",
1396 INITTAB, lineNo, id);
1397 break;
1398 }
1399 }
1400 if (old) continue;
1401
1402 /*
1403 * Allocate a CHILD structure
1404 */
1405 ch = imalloc(sizeof(CHILD));
1406
1407 /*
1408 * And fill it in.
1409 */
1410 ch->action = actionNo;
1411 strncpy(ch->id, id, sizeof(utproto.ut_id) + 1); /* Hack for different libs. */
1412 strncpy(ch->process, process, sizeof(ch->process) - 1);
1413 if (rlevel[0]) {
1414 for(f = 0; f < (int)sizeof(rlevel) - 1 && rlevel[f]; f++) {
1415 ch->rlevel[f] = rlevel[f];
1416 if (ch->rlevel[f] == 's') ch->rlevel[f] = 'S';
1417 }
1418 strncpy(ch->rlevel, rlevel, sizeof(ch->rlevel) - 1);
1419 } else {
1420 strcpy(ch->rlevel, "0123456789");
1421 if (ISPOWER(ch->action))
1422 strcpy(ch->rlevel, "S0123456789");
1423 }
1424 /*
1425 * We have the fake runlevel '#' for SYSINIT and
1426 * '*' for BOOT and BOOTWAIT.
1427 */
1428 if (ch->action == SYSINIT) strcpy(ch->rlevel, "#");
1429 if (ch->action == BOOT || ch->action == BOOTWAIT)
1430 strcpy(ch->rlevel, "*");
1431
1432 /*
1433 * Now add it to the linked list. Special for powerfail.
1434 */
1435 if (ISPOWER(ch->action)) {
1436
1437 /*
1438 * Disable by default
1439 */
1440 ch->flags |= XECUTED;
1441
1442 /*
1443 * Tricky: insert at the front of the list..
1444 */
1445 old = NULL;
1446 for(i = newFamily; i; i = i->next) {
1447 if (!ISPOWER(i->action)) break;
1448 old = i;
1449 }
1450 /*
1451 * Now add after entry "old"
1452 */
1453 if (old) {
1454 ch->next = i;
1455 old->next = ch;
1456 if (i == NULL) head = ch;
1457 } else {
1458 ch->next = newFamily;
1459 newFamily = ch;
1460 if (ch->next == NULL) head = ch;
1461 }
1462 } else {
1463 /*
1464 * Just add at end of the list
1465 */
1466 if (ch->action == KBREQUEST) ch->flags |= XECUTED;
1467 ch->next = NULL;
1468 if (head)
1469 head->next = ch;
1470 else
1471 newFamily = ch;
1472 head = ch;
1473 }
1474
1475 /*
1476 * Walk through the old list comparing id fields
1477 */
1478 for(old = family; old; old = old->next)
1479 if (strcmp(old->id, ch->id) == 0) {
1480 old->new = ch;
1481 break;
1482 }
1483 }
1484 /*
1485 * We're done.
1486 */
1487 if (fp) fclose(fp);
1488
1489 /*
1490 * Loop through the list of children, and see if they need to
1491 * be killed.
1492 */
1493
1494 INITDBG(L_VB, "Checking for children to kill");
1495 for(round = 0; round < 2; round++) {
1496 talk = 1;
1497 for(ch = family; ch; ch = ch->next) {
1498 ch->flags &= ~KILLME;
1499
1500 /*
1501 * Is this line deleted?
1502 */
1503 if (ch->new == NULL) ch->flags |= KILLME;
1504
1505 /*
1506 * If the entry has changed, kill it anyway. Note that
1507 * we do not check ch->process, only the "action" field.
1508 * This way, you can turn an entry "off" immediately, but
1509 * changes in the command line will only become effective
1510 * after the running version has exited.
1511 */
1512 if (ch->new && ch->action != ch->new->action) ch->flags |= KILLME;
1513
1514 /*
1515 * Only BOOT processes may live in all levels
1516 */
1517 if (ch->action != BOOT &&
1518 strchr(ch->rlevel, runlevel) == NULL) {
1519 /*
1520 * Ondemand procedures live always,
1521 * except in single user
1522 */
1523 if (runlevel == 'S' || !(ch->flags & DEMAND))
1524 ch->flags |= KILLME;
1525 }
1526
1527 /*
1528 * Now, if this process may live note so in the new list
1529 */
1530 if ((ch->flags & KILLME) == 0) {
1531 ch->new->flags = ch->flags;
1532 ch->new->pid = ch->pid;
1533 ch->new->exstat = ch->exstat;
1534 continue;
1535 }
1536
1537
1538 /*
1539 * Is this process still around?
1540 */
1541 if ((ch->flags & RUNNING) == 0) {
1542 ch->flags &= ~KILLME;
1543 continue;
1544 }
1545 INITDBG(L_VB, "Killing \"%s\"", ch->process);
1546 switch(round) {
1547 case 0: /* Send TERM signal */
1548 if (talk)
1549 initlog(L_CO,
1550 "Sending processes configured via /etc/inittab the TERM signal");
1551 kill(-(ch->pid), SIGTERM);
1552 foundOne = 1;
1553 break;
1554 case 1: /* Send KILL signal and collect status */
1555 if (talk)
1556 initlog(L_CO,
1557 "Sending processes configured via /etc/inittab the KILL signal");
1558 kill(-(ch->pid), SIGKILL);
1559 break;
1560 }
1561 talk = 0;
1562
1563 }
1564 /*
1565 * See if we have to wait 5 seconds
1566 */
1567 if (foundOne && round == 0) {
1568 /*
1569 * Yup, but check every second if we still have children.
1570 */
1571 for(f = 0; f < sltime; f++) {
1572 for(ch = family; ch; ch = ch->next) {
1573 if (!(ch->flags & KILLME)) continue;
1574 if ((ch->flags & RUNNING) && !(ch->flags & ZOMBIE))
1575 break;
1576 }
1577 if (ch == NULL) {
1578 /*
1579 * No running children, skip SIGKILL
1580 */
1581 round = 1;
1582 foundOne = 0; /* Skip the sleep below. */
1583 break;
1584 }
1585 do_sleep(1);
1586 }
1587 }
1588 }
1589
1590 /*
1591 * Now give all processes the chance to die and collect exit statuses.
1592 */
1593 if (foundOne) do_sleep(1);
1594 for(ch = family; ch; ch = ch->next)
1595 if (ch->flags & KILLME) {
1596 if (!(ch->flags & ZOMBIE))
1597 initlog(L_CO, "Pid %d [id %s] seems to hang", ch->pid,
1598 ch->id);
1599 else {
1600 INITDBG(L_VB, "Updating utmp for pid %d [id %s]",
1601 ch->pid, ch->id);
1602 ch->flags &= ~RUNNING;
1603 if (ch->process[0] != '+')
1604 write_utmp_wtmp("", ch->id, ch->pid, DEAD_PROCESS, NULL);
1605 }
1606 }
1607
1608 /*
1609 * Both rounds done; clean up the list.
1610 */
1611 sigemptyset(&nmask);
1612 sigaddset(&nmask, SIGCHLD);
1613 sigprocmask(SIG_BLOCK, &nmask, &omask);
1614 for(ch = family; ch; ch = old) {
1615 old = ch->next;
1616 free(ch);
1617 }
1618 family = newFamily;
1619 for(ch = family; ch; ch = ch->next) ch->new = NULL;
1620 newFamily = NULL;
1621 sigprocmask(SIG_SETMASK, &omask, NULL);
1622
1623 #ifdef INITLVL
1624 /*
1625 * Dispose of INITLVL file.
1626 */
1627 if (lstat(INITLVL, &st) >= 0 && S_ISLNK(st.st_mode)) {
1628 /*
1629 * INITLVL is a symbolic link, so just truncate the file.
1630 */
1631 close(open(INITLVL, O_WRONLY|O_TRUNC));
1632 } else {
1633 /*
1634 * Delete INITLVL file.
1635 */
1636 unlink(INITLVL);
1637 }
1638 #endif
1639 #ifdef INITLVL2
1640 /*
1641 * Dispose of INITLVL2 file.
1642 */
1643 if (lstat(INITLVL2, &st) >= 0 && S_ISLNK(st.st_mode)) {
1644 /*
1645 * INITLVL2 is a symbolic link, so just truncate the file.
1646 */
1647 close(open(INITLVL2, O_WRONLY|O_TRUNC));
1648 } else {
1649 /*
1650 * Delete INITLVL2 file.
1651 */
1652 unlink(INITLVL2);
1653 }
1654 #endif
1655 }
1656
1657 /*
1658 * Walk through the family list and start up children.
1659 * The entries that do not belong here at all are removed
1660 * from the list.
1661 */
1662 static
1663 void start_if_needed(void)
1664 {
1665 CHILD *ch; /* Pointer to child */
1666 int delete; /* Delete this entry from list? */
1667
1668 INITDBG(L_VB, "Checking for children to start");
1669
1670 for(ch = family; ch; ch = ch->next) {
1671
1672 #if DEBUG
1673 if (ch->rlevel[0] == 'C') {
1674 INITDBG(L_VB, "%s: flags %d", ch->process, ch->flags);
1675 }
1676 #endif
1677
1678 /* Are we waiting for this process? Then quit here. */
1679 if (ch->flags & WAITING) break;
1680
1681 /* Already running? OK, don't touch it */
1682 if (ch->flags & RUNNING) continue;
1683
1684 /* See if we have to start it up */
1685 delete = 1;
1686 if (strchr(ch->rlevel, runlevel) ||
1687 ((ch->flags & DEMAND) && !strchr("#*Ss", runlevel))) {
1688 startup(ch);
1689 delete = 0;
1690 }
1691
1692 if (delete) {
1693 /* FIXME: is this OK? */
1694 ch->flags &= ~(RUNNING|WAITING);
1695 if (!ISPOWER(ch->action) && ch->action != KBREQUEST)
1696 ch->flags &= ~XECUTED;
1697 ch->pid = 0;
1698 } else
1699 /* Do we have to wait for this process? */
1700 if (ch->flags & WAITING) break;
1701 }
1702 /* Done. */
1703 }
1704
1705 /*
1706 * Ask the user on the console for a runlevel
1707 */
1708 static
1709 int ask_runlevel(void)
1710 {
1711 const char prompt[] = "\nEnter runlevel: ";
1712 char buf[8];
1713 int lvl = -1;
1714 int fd;
1715
1716 console_stty();
1717 fd = console_open(O_RDWR|O_NOCTTY);
1718
1719 if (fd < 0) return('S');
1720
1721 while(!strchr("0123456789S", lvl)) {
1722 safe_write(fd, prompt, sizeof(prompt) - 1);
1723 if (read(fd, buf, sizeof(buf)) <= 0)
1724 buf[0] = 0;
1725 if (buf[0] != 0 && (buf[1] == '\r' || buf[1] == '\n'))
1726 lvl = buf[0];
1727 if (islower(lvl)) lvl = toupper(lvl);
1728 }
1729 close(fd);
1730 return lvl;
1731 }
1732
1733 /*
1734 * Search the INITTAB file for the 'initdefault' field, with the default
1735 * runlevel. If this fails, ask the user to supply a runlevel.
1736 */
1737 static
1738 int get_init_default(void)
1739 {
1740 CHILD *ch;
1741 int lvl = -1;
1742 char *p;
1743
1744 /*
1745 * Look for initdefault.
1746 */
1747 for(ch = family; ch; ch = ch->next)
1748 if (ch->action == INITDEFAULT) {
1749 p = ch->rlevel;
1750 while(*p) {
1751 if (*p > lvl) lvl = *p;
1752 p++;
1753 }
1754 break;
1755 }
1756 /*
1757 * See if level is valid
1758 */
1759 if (lvl > 0) {
1760 if (islower(lvl)) lvl = toupper(lvl);
1761 if (strchr("0123456789S", lvl) == NULL) {
1762 initlog(L_VB,
1763 "Initdefault level '%c' is invalid", lvl);
1764 lvl = 0;
1765 }
1766 }
1767 /*
1768 * Ask for runlevel on console if needed.
1769 */
1770 if (lvl <= 0) lvl = ask_runlevel();
1771
1772 /*
1773 * Log the fact that we have a runlevel now.
1774 */
1775 return lvl;
1776 }
1777
1778
1779 /*
1780 * We got signaled.
1781 *
1782 * Do actions for the new level. If we are compatible with
1783 * the "old" INITLVL and arg == 0, try to read the new
1784 * runlevel from that file first.
1785 */
1786 static
1787 int read_level(int arg)
1788 {
1789 CHILD *ch; /* Walk through list */
1790 unsigned char foo = 'X'; /* Contents of INITLVL */
1791 int ok = 1;
1792 #ifdef INITLVL
1793 FILE *fp;
1794 struct stat stt;
1795 int st;
1796 #endif
1797
1798 if (arg) foo = arg;
1799
1800 #ifdef INITLVL
1801 ok = 0;
1802
1803 if (arg == 0) {
1804 fp = NULL;
1805 if (stat(INITLVL, &stt) != 0 || stt.st_size != 0L)
1806 fp = fopen(INITLVL, "r");
1807 #ifdef INITLVL2
1808 if (fp == NULL &&
1809 (stat(INITLVL2, &stt) != 0 || stt.st_size != 0L))
1810 fp = fopen(INITLVL2, "r");
1811 #endif
1812 if (fp == NULL) {
1813 /* INITLVL file empty or not there - act as 'init q' */
1814 initlog(L_SY, "Re-reading inittab");
1815 return(runlevel);
1816 }
1817 ok = fscanf(fp, "%c %d", &foo, &st);
1818 fclose(fp);
1819 } else {
1820 /* We go to the new runlevel passed as an argument. */
1821 foo = arg;
1822 ok = 1;
1823 }
1824 if (ok == 2) sltime = st;
1825
1826 #endif /* INITLVL */
1827
1828 if (islower(foo)) foo = toupper(foo);
1829 if (ok < 1 || ok > 2 || strchr("QS0123456789ABCU", foo) == NULL) {
1830 initlog(L_VB, "bad runlevel: %c", foo);
1831 return runlevel;
1832 }
1833
1834 /* Log this action */
1835 switch(foo) {
1836 case 'S':
1837 initlog(L_VB, "Going single user");
1838 break;
1839 case 'Q':
1840 initlog(L_SY, "Re-reading inittab");
1841 break;
1842 case 'A':
1843 case 'B':
1844 case 'C':
1845 initlog(L_SY,
1846 "Activating demand-procedures for '%c'", foo);
1847 break;
1848 case 'U':
1849 initlog(L_SY, "Trying to re-exec init");
1850 return 'U';
1851 default:
1852 initlog(L_VB, "Switching to runlevel: %c", foo);
1853 }
1854
1855 if (foo == 'Q') {
1856 #if defined(SIGINT_ONLYONCE) && (SIGINT_ONLYONCE == 1)
1857 /* Re-enable signal from keyboard */
1858 struct sigaction sa;
1859 SETSIG(sa, SIGINT, signal_handler, 0);
1860 #endif
1861 return runlevel;
1862 }
1863
1864 /* Check if this is a runlevel a, b or c */
1865 if (strchr("ABC", foo)) {
1866 if (runlevel == 'S') return(runlevel);
1867
1868 /* Read inittab again first! */
1869 read_inittab();
1870
1871 /* Mark those special tasks */
1872 for(ch = family; ch; ch = ch->next)
1873 if (strchr(ch->rlevel, foo) != NULL ||
1874 strchr(ch->rlevel, tolower(foo)) != NULL) {
1875 ch->flags |= DEMAND;
1876 ch->flags &= ~XECUTED;
1877 INITDBG(L_VB,
1878 "Marking (%s) as ondemand, flags %d",
1879 ch->id, ch->flags);
1880 }
1881 return runlevel;
1882 }
1883
1884 /* Store both the old and the new runlevel. */
1885 wrote_utmp_rlevel = 0;
1886 wrote_wtmp_rlevel = 0;
1887 write_utmp_wtmp("runlevel", "~~", foo + 256*runlevel, RUN_LVL, "~");
1888 thislevel = foo;
1889 prevlevel = runlevel;
1890 return foo;
1891 }
1892
1893
1894 /*
1895 * This procedure is called after every signal (SIGHUP, SIGALRM..)
1896 *
1897 * Only clear the 'failing' flag if the process is sleeping
1898 * longer than 5 minutes, or inittab was read again due
1899 * to user interaction.
1900 */
1901 static
1902 void fail_check(void)
1903 {
1904 CHILD *ch; /* Pointer to child structure */
1905 time_t t; /* System time */
1906 time_t next_alarm = 0; /* When to set next alarm */
1907
1908 time(&t);
1909
1910 for(ch = family; ch; ch = ch->next) {
1911
1912 if (ch->flags & FAILING) {
1913 /* Can we free this sucker? */
1914 if (ch->tm + SLEEPTIME < t) {
1915 ch->flags &= ~FAILING;
1916 ch->count = 0;
1917 ch->tm = 0;
1918 } else {
1919 /* No, we'll look again later */
1920 if (next_alarm == 0 ||
1921 ch->tm + SLEEPTIME > next_alarm)
1922 next_alarm = ch->tm + SLEEPTIME;
1923 }
1924 }
1925 }
1926 if (next_alarm) {
1927 next_alarm -= t;
1928 if (next_alarm < 1) next_alarm = 1;
1929 alarm(next_alarm);
1930 }
1931 }
1932
1933 /* Set all 'Fail' timers to 0 */
1934 static
1935 void fail_cancel(void)
1936 {
1937 CHILD *ch;
1938
1939 for(ch = family; ch; ch = ch->next) {
1940 ch->count = 0;
1941 ch->tm = 0;
1942 ch->flags &= ~FAILING;
1943 }
1944 }
1945
1946 /*
1947 * Start up powerfail entries.
1948 */
1949 static
1950 void do_power_fail(int pwrstat)
1951 {
1952 CHILD *ch;
1953
1954 /*
1955 * Tell powerwait & powerfail entries to start up
1956 */
1957 for (ch = family; ch; ch = ch->next) {
1958 if (pwrstat == 'O') {
1959 /*
1960 * The power is OK again.
1961 */
1962 if (ch->action == POWEROKWAIT)
1963 ch->flags &= ~XECUTED;
1964 } else if (pwrstat == 'L') {
1965 /*
1966 * Low battery, shut down now.
1967 */
1968 if (ch->action == POWERFAILNOW)
1969 ch->flags &= ~XECUTED;
1970 } else {
1971 /*
1972 * Power is failing, shutdown imminent
1973 */
1974 if (ch->action == POWERFAIL || ch->action == POWERWAIT)
1975 ch->flags &= ~XECUTED;
1976 }
1977 }
1978 }
1979
1980 /*
1981 * Check for state-pipe presence
1982 */
1983 static
1984 int check_pipe(int fd)
1985 {
1986 struct timeval t;
1987 fd_set s;
1988 char signature[8];
1989
1990 FD_ZERO(&s);
1991 FD_SET(fd, &s);
1992 t.tv_sec = t.tv_usec = 0;
1993
1994 if (select(fd+1, &s, NULL, NULL, &t) != 1)
1995 return 0;
1996 if (read(fd, signature, 8) != 8)
1997 return 0;
1998 return strncmp(Signature, signature, 8) == 0;
1999 }
2000
2001 /*
2002 * Make a state-pipe.
2003 */
2004 static
2005 int make_pipe(int fd)
2006 {
2007 int fds[2];
2008
2009 if (pipe(fds)) {
2010 initlog(L_VB, "pipe: %m");
2011 return -1;
2012 }
2013 dup2(fds[0], fd);
2014 close(fds[0]);
2015 fcntl(fds[1], F_SETFD, 1);
2016 fcntl(fd, F_SETFD, 0);
2017 safe_write(fds[1], Signature, 8);
2018
2019 return fds[1];
2020 }
2021
2022 /*
2023 * Attempt to re-exec.
2024 */
2025 static
2026 void re_exec(void)
2027 {
2028 CHILD *ch;
2029 sigset_t mask, oldset;
2030 pid_t pid;
2031 char **env;
2032 int fd;
2033
2034 if (strchr("S0123456",runlevel) == NULL)
2035 return;
2036
2037 /*
2038 * Reset the alarm, and block all signals.
2039 */
2040 alarm(0);
2041 sigfillset(&mask);
2042 sigprocmask(SIG_BLOCK, &mask, &oldset);
2043
2044 /*
2045 * construct a pipe fd --> STATE_PIPE and write a signature
2046 */
2047 if ((fd = make_pipe(STATE_PIPE)) < 0) {
2048 sigprocmask(SIG_SETMASK, &oldset, NULL);
2049 initlog(L_CO, "Attempt to re-exec failed");
2050 }
2051
2052 /*
2053 * It's a backup day today, so I'm pissed off. Being a BOFH, however,
2054 * does have it's advantages...
2055 */
2056 fail_cancel();
2057 close(pipe_fd);
2058 pipe_fd = -1;
2059 DELSET(got_signals, SIGCHLD);
2060 DELSET(got_signals, SIGHUP);
2061 DELSET(got_signals, SIGUSR1);
2062
2063 /*
2064 * That should be cleaned.
2065 */
2066 for(ch = family; ch; ch = ch->next)
2067 if (ch->flags & ZOMBIE) {
2068 INITDBG(L_VB, "Child died, PID= %d", ch->pid);
2069 ch->flags &= ~(RUNNING|ZOMBIE|WAITING);
2070 if (ch->process[0] != '+')
2071 write_utmp_wtmp("", ch->id, ch->pid, DEAD_PROCESS, NULL);
2072 }
2073
2074 if ((pid = fork()) == 0) {
2075 /*
2076 * Child sends state information to the parent.
2077 */
2078 send_state(fd);
2079 exit(0);
2080 }
2081
2082 /*
2083 * The existing init process execs a new init binary.
2084 */
2085 env = init_buildenv(0);
2086 execle(myname, myname, "--init", NULL, env);
2087
2088 /*
2089 * We shouldn't be here, something failed.
2090 * Bitch, close the state pipe, unblock signals and return.
2091 */
2092 init_freeenv(env);
2093 close(fd);
2094 close(STATE_PIPE);
2095 sigprocmask(SIG_SETMASK, &oldset, NULL);
2096 initlog(L_CO, "Attempt to re-exec failed");
2097 }
2098
2099 /*
2100 * Redo utmp/wtmp entries if required or requested
2101 * Check for written records and size of utmp
2102 */
2103 static
2104 void redo_utmp_wtmp(void)
2105 {
2106 struct stat ustat;
2107 const int ret = stat(UTMP_FILE, &ustat);
2108
2109 if ((ret < 0) || (ustat.st_size == 0))
2110 wrote_utmp_rlevel = wrote_utmp_reboot = 0;
2111
2112 if ((wrote_wtmp_reboot == 0) || (wrote_utmp_reboot == 0))
2113 write_utmp_wtmp("reboot", "~~", 0, BOOT_TIME, "~");
2114
2115 if ((wrote_wtmp_rlevel == 0) || (wrote_wtmp_rlevel == 0))
2116 write_utmp_wtmp("runlevel", "~~", thislevel + 256 * prevlevel, RUN_LVL, "~");
2117 }
2118
2119 /*
2120 * We got a change runlevel request through the
2121 * init.fifo. Process it.
2122 */
2123 static
2124 void fifo_new_level(int level)
2125 {
2126 #if CHANGE_WAIT
2127 CHILD *ch;
2128 #endif
2129 int oldlevel;
2130
2131 if (level == runlevel) return;
2132
2133 #if CHANGE_WAIT
2134 /* Are we waiting for a child? */
2135 for(ch = family; ch; ch = ch->next)
2136 if (ch->flags & WAITING) break;
2137 if (ch == NULL)
2138 #endif
2139 {
2140 /* We need to go into a new runlevel */
2141 oldlevel = runlevel;
2142 runlevel = read_level(level);
2143 if (runlevel == 'U') {
2144 runlevel = oldlevel;
2145 re_exec();
2146 } else {
2147 if (oldlevel != 'S' && runlevel == 'S') console_stty();
2148 if (runlevel == '6' || runlevel == '0' ||
2149 runlevel == '1') console_stty();
2150 if (runlevel > '1' && runlevel < '6') redo_utmp_wtmp();
2151 read_inittab();
2152 fail_cancel();
2153 setproctitle("init [%c]", (int)runlevel);
2154 }
2155 }
2156 }
2157
2158
2159 /*
2160 * Set/unset environment variables. The variables are
2161 * encoded as KEY=VAL\0KEY=VAL\0\0. With "=VAL" it means
2162 * setenv, without it means unsetenv.
2163 */
2164 static
2165 void initcmd_setenv(char *data, int size)
2166 {
2167 char *env, *p, *e;
2168 size_t sz;
2169 int i, eq;
2170
2171 e = data + size;
2172
2173 while (*data && data < e) {
2174 for (p = data; *p && p < e; p++)
2175 ;
2176 if (*p) break;
2177 env = data;
2178 data = ++p;
2179
2180 /*
2181 * We only allow INIT_* to be set.
2182 */
2183 if (strncmp(env, "INIT_", 5) != 0)
2184 continue;
2185
2186 sz = strcspn(env, "=");
2187 eq = (env[sz] == '=');
2188
2189 /*initlog(L_SY, "init_setenv: %s, %d, %d", env, eq, sz);*/
2190
2191 /* Free existing vars. */
2192 for (i = 0; i < NR_EXTRA_ENV; i++) {
2193 if (extra_env[i] == NULL)
2194 continue;
2195 if (sz != strcspn(extra_env[i], "="))
2196 continue;
2197 if (strncmp(extra_env[i], env, sz) == 0) {
2198 free(extra_env[i]);
2199 extra_env[i] = NULL;
2200 }
2201 }
2202
2203 if (eq == 0)
2204 continue;
2205
2206 /* Set new vars if needed. */
2207 for (i = 0; i < NR_EXTRA_ENV; i++) {
2208 if (extra_env[i] == NULL) {
2209 extra_env[i] = istrdup(env);
2210 break;
2211 }
2212 }
2213 }
2214 }
2215
2216
2217 /*
2218 * Read from the init FIFO. Processes like telnetd and rlogind can
2219 * ask us to create login processes on their behalf.
2220 *
2221 * FIXME: this needs to be finished. NOT that it is buggy, but we need
2222 * to add the telnetd/rlogind stuff so people can start using it.
2223 * Maybe move to using an AF_UNIX socket so we can use
2224 * the 2.2 kernel credential stuff to see who we're talking to.
2225 *
2226 */
2227 static
2228 void check_init_fifo(void)
2229 {
2230 struct init_request request;
2231 struct timeval tv;
2232 struct stat st, st2;
2233 fd_set fds;
2234 int n;
2235 int quit = 0;
2236
2237 /*
2238 * First, try to create /dev/initctl if not present.
2239 */
2240 if (stat(INIT_FIFO, &st2) < 0 && errno == ENOENT)
2241 (void)mkfifo(INIT_FIFO, 0600);
2242
2243 /*
2244 * If /dev/initctl is open, stat the file to see if it
2245 * is still the _same_ inode.
2246 */
2247 if (pipe_fd >= 0) {
2248 fstat(pipe_fd, &st);
2249 if (stat(INIT_FIFO, &st2) < 0 ||
2250 st.st_dev != st2.st_dev ||
2251 st.st_ino != st2.st_ino) {
2252 close(pipe_fd);
2253 pipe_fd = -1;
2254 }
2255 }
2256
2257 /*
2258 * Now finally try to open /dev/initctl
2259 */
2260 if (pipe_fd < 0) {
2261 if ((pipe_fd = open(INIT_FIFO, O_RDWR|O_NONBLOCK)) >= 0) {
2262 fstat(pipe_fd, &st);
2263 if (!S_ISFIFO(st.st_mode)) {
2264 initlog(L_VB, "%s is not a fifo", INIT_FIFO);
2265 close(pipe_fd);
2266 pipe_fd = -1;
2267 }
2268 }
2269 if (pipe_fd >= 0) {
2270 /*
2271 * Don't use fd's 0, 1 or 2.
2272 */
2273 (void) dup2(pipe_fd, PIPE_FD);
2274 close(pipe_fd);
2275 pipe_fd = PIPE_FD;
2276
2277 /*
2278 * Return to caller - we'll be back later.
2279 */
2280 }
2281 }
2282
2283 /* Wait for data to appear, _if_ the pipe was opened. */
2284 if (pipe_fd >= 0) while(!quit) {
2285
2286 /* Do select, return on EINTR. */
2287 FD_ZERO(&fds);
2288 FD_SET(pipe_fd, &fds);
2289 tv.tv_sec = 5;
2290 tv.tv_usec = 0;
2291 n = select(pipe_fd + 1, &fds, NULL, NULL, &tv);
2292 if (n <= 0) {
2293 if (n == 0 || errno == EINTR) return;
2294 continue;
2295 }
2296
2297 /* Read the data, return on EINTR. */
2298 n = read(pipe_fd, &request, sizeof(request));
2299 if (n == 0) {
2300 /*
2301 * End of file. This can't happen under Linux (because
2302 * the pipe is opened O_RDWR - see select() in the
2303 * kernel) but you never know...
2304 */
2305 close(pipe_fd);
2306 pipe_fd = -1;
2307 return;
2308 }
2309 if (n <= 0) {
2310 if (errno == EINTR) return;
2311 initlog(L_VB, "error reading initrequest");
2312 continue;
2313 }
2314
2315 /*
2316 * This is a convenient point to also try to
2317 * find the console device or check if it changed.
2318 */
2319 console_init();
2320
2321 /*
2322 * Process request.
2323 */
2324 if (request.magic != INIT_MAGIC || n != sizeof(request)) {
2325 initlog(L_VB, "got bogus initrequest");
2326 continue;
2327 }
2328 switch(request.cmd) {
2329 case INIT_CMD_RUNLVL:
2330 sltime = request.sleeptime;
2331 fifo_new_level(request.runlevel);
2332 quit = 1;
2333 break;
2334 case INIT_CMD_POWERFAIL:
2335 sltime = request.sleeptime;
2336 do_power_fail('F');
2337 quit = 1;
2338 break;
2339 case INIT_CMD_POWERFAILNOW:
2340 sltime = request.sleeptime;
2341 do_power_fail('L');
2342 quit = 1;
2343 break;
2344 case INIT_CMD_POWEROK:
2345 sltime = request.sleeptime;
2346 do_power_fail('O');
2347 quit = 1;
2348 break;
2349 case INIT_CMD_SETENV:
2350 initcmd_setenv(request.i.data, sizeof(request.i.data));
2351 break;
2352 default:
2353 initlog(L_VB, "got unimplemented initrequest.");
2354 break;
2355 }
2356 }
2357
2358 /*
2359 * We come here if the pipe couldn't be opened.
2360 */
2361 if (pipe_fd < 0) pause();
2362
2363 }
2364
2365
2366 /*
2367 * This function is used in the transition
2368 * sysinit (-> single user) boot -> multi-user.
2369 */
2370 static
2371 void boot_transitions()
2372 {
2373 CHILD *ch;
2374 static int newlevel = 0;
2375 static int warn = 1;
2376 int loglevel;
2377 int oldlevel;
2378
2379 /* Check if there is something to wait for! */
2380 for( ch = family; ch; ch = ch->next )
2381 if ((ch->flags & RUNNING) && ch->action != BOOT) break;
2382
2383 if (ch == NULL) {
2384 /* No processes left in this level, proceed to next level. */
2385 loglevel = -1;
2386 oldlevel = 'N';
2387 switch(runlevel) {
2388 case '#': /* SYSINIT -> BOOT */
2389 INITDBG(L_VB, "SYSINIT -> BOOT");
2390
2391 /* Write a boot record. */
2392 wrote_utmp_reboot = 0;
2393 wrote_wtmp_reboot = 0;
2394 write_utmp_wtmp("reboot", "~~", 0, BOOT_TIME, "~");
2395
2396 /* Get our run level */
2397 newlevel = dfl_level ? dfl_level : get_init_default();
2398 if (newlevel == 'S') {
2399 runlevel = newlevel;
2400 /* Not really 'S' but show anyway. */
2401 setproctitle("init [S]");
2402 } else
2403 runlevel = '*';
2404 break;
2405 case '*': /* BOOT -> NORMAL */
2406 INITDBG(L_VB, "BOOT -> NORMAL");
2407 if (runlevel != newlevel)
2408 loglevel = newlevel;
2409 runlevel = newlevel;
2410 did_boot = 1;
2411 warn = 1;
2412 break;
2413 case 'S': /* Ended SU mode */
2414 case 's':
2415 INITDBG(L_VB, "END SU MODE");
2416 newlevel = get_init_default();
2417 if (!did_boot && newlevel != 'S')
2418 runlevel = '*';
2419 else {
2420 if (runlevel != newlevel)
2421 loglevel = newlevel;
2422 runlevel = newlevel;
2423 oldlevel = 'S';
2424 }
2425 warn = 1;
2426 for(ch = family; ch; ch = ch->next)
2427 if (strcmp(ch->rlevel, "S") == 0)
2428 ch->flags &= ~(FAILING|WAITING|XECUTED);
2429 break;
2430 default:
2431 if (warn)
2432 initlog(L_VB,
2433 "no more processes left in this runlevel");
2434 warn = 0;
2435 loglevel = -1;
2436 if (got_signals == 0)
2437 check_init_fifo();
2438 break;
2439 }
2440 if (loglevel > 0) {
2441 initlog(L_VB, "Entering runlevel: %c", runlevel);
2442 wrote_utmp_rlevel = 0;
2443 wrote_wtmp_rlevel = 0;
2444 write_utmp_wtmp("runlevel", "~~", runlevel + 256 * oldlevel, RUN_LVL, "~");
2445 thislevel = runlevel;
2446 prevlevel = oldlevel;
2447 setproctitle("init [%c]", (int)runlevel);
2448 }
2449 }
2450 }
2451
2452 /*
2453 * Init got hit by a signal. See which signal it is,
2454 * and act accordingly.
2455 */
2456 static
2457 void process_signals()
2458 {
2459 CHILD *ch;
2460 int pwrstat;
2461 int oldlevel;
2462 int fd;
2463 char c;
2464
2465 if (ISMEMBER(got_signals, SIGPWR)) {
2466 INITDBG(L_VB, "got SIGPWR");
2467 /* See _what_ kind of SIGPWR this is. */
2468 pwrstat = 0;
2469 if ((fd = open(PWRSTAT, O_RDONLY)) >= 0) {
2470 if (read(fd, &c, 1) != 1)
2471 c = 0;
2472 pwrstat = c;
2473 close(fd);
2474 unlink(PWRSTAT);
2475 } else if ((fd = open(PWRSTAT_OLD, O_RDONLY)) >= 0) {
2476 /* Path changed 2010-03-20. Look for the old path for a while. */
2477 initlog(L_VB, "warning: found obsolete path %s, use %s instead",
2478 PWRSTAT_OLD, PWRSTAT);
2479 if (read(fd, &c, 1) != 1)
2480 c = 0;
2481 pwrstat = c;
2482 close(fd);
2483 unlink(PWRSTAT_OLD);
2484 }
2485 do_power_fail(pwrstat);
2486 DELSET(got_signals, SIGPWR);
2487 }
2488
2489 if (ISMEMBER(got_signals, SIGINT)) {
2490 #if defined(SIGINT_ONLYONCE) && (SIGINT_ONLYONCE == 1)
2491 /* Ignore any further signal from keyboard */
2492 struct sigaction sa;
2493 SETSIG(sa, SIGINT, SIG_IGN, SA_RESTART);
2494 #endif
2495 INITDBG(L_VB, "got SIGINT");
2496 /* Tell ctrlaltdel entry to start up */
2497 for(ch = family; ch; ch = ch->next)
2498 if (ch->action == CTRLALTDEL)
2499 ch->flags &= ~XECUTED;
2500 DELSET(got_signals, SIGINT);
2501 }
2502
2503 if (ISMEMBER(got_signals, SIGWINCH)) {
2504 INITDBG(L_VB, "got SIGWINCH");
2505 /* Tell kbrequest entry to start up */
2506 for(ch = family; ch; ch = ch->next)
2507 if (ch->action == KBREQUEST)
2508 ch->flags &= ~XECUTED;
2509 DELSET(got_signals, SIGWINCH);
2510 }
2511
2512 if (ISMEMBER(got_signals, SIGALRM)) {
2513 INITDBG(L_VB, "got SIGALRM");
2514 /* The timer went off: check it out */
2515 DELSET(got_signals, SIGALRM);
2516 }
2517
2518 if (ISMEMBER(got_signals, SIGCHLD)) {
2519 INITDBG(L_VB, "got SIGCHLD");
2520 /* First set flag to 0 */
2521 DELSET(got_signals, SIGCHLD);
2522
2523 /* See which child this was */
2524 for(ch = family; ch; ch = ch->next)
2525 if (ch->flags & ZOMBIE) {
2526 INITDBG(L_VB, "Child died, PID= %d", ch->pid);
2527 ch->flags &= ~(RUNNING|ZOMBIE|WAITING);
2528 if (ch->process[0] != '+')
2529 write_utmp_wtmp("", ch->id, ch->pid, DEAD_PROCESS, NULL);
2530 }
2531
2532 }
2533
2534 if (ISMEMBER(got_signals, SIGHUP)) {
2535 INITDBG(L_VB, "got SIGHUP");
2536 #if CHANGE_WAIT
2537 /* Are we waiting for a child? */
2538 for(ch = family; ch; ch = ch->next)
2539 if (ch->flags & WAITING) break;
2540 if (ch == NULL)
2541 #endif
2542 {
2543 /* We need to go into a new runlevel */
2544 oldlevel = runlevel;
2545 #ifdef INITLVL
2546 runlevel = read_level(0);
2547 #endif
2548 if (runlevel == 'U') {
2549 runlevel = oldlevel;
2550 re_exec();
2551 } else {
2552 if (oldlevel != 'S' && runlevel == 'S') console_stty();
2553 if (runlevel == '6' || runlevel == '0' ||
2554 runlevel == '1') console_stty();
2555 read_inittab();
2556 fail_cancel();
2557 setproctitle("init [%c]", (int)runlevel);
2558 DELSET(got_signals, SIGHUP);
2559 }
2560 }
2561 }
2562 if (ISMEMBER(got_signals, SIGUSR1)) {
2563 /*
2564 * SIGUSR1 means close and reopen /dev/initctl
2565 */
2566 INITDBG(L_VB, "got SIGUSR1");
2567 close(pipe_fd);
2568 pipe_fd = -1;
2569 DELSET(got_signals, SIGUSR1);
2570 }
2571 }
2572
2573 /*
2574 * The main loop
2575 */
2576 static
2577 void init_main(void)
2578 {
2579 CHILD *ch;
2580 struct sigaction sa;
2581 sigset_t sgt;
2582 int f, st;
2583
2584 if (!reload) {
2585
2586 #if INITDEBUG
2587 /*
2588 * Fork so we can debug the init process.
2589 */
2590 if ((f = fork()) > 0) {
2591 static const char killmsg[] = "PRNT: init killed.\r\n";
2592 pid_t rc;
2593
2594 while((rc = wait(&st)) != f)
2595 if (rc < 0 && errno == ECHILD)
2596 break;
2597 safe_write(1, killmsg, sizeof(killmsg) - 1);
2598 while(1) pause();
2599 }
2600 #endif
2601
2602 #ifdef __linux__
2603 /*
2604 * Tell the kernel to send us SIGINT when CTRL-ALT-DEL
2605 * is pressed, and that we want to handle keyboard signals.
2606 */
2607 init_reboot(BMAGIC_SOFT);
2608 if ((f = open(VT_MASTER, O_RDWR | O_NOCTTY)) >= 0) {
2609 (void) ioctl(f, KDSIGACCEPT, SIGWINCH);
2610 close(f);
2611 } else
2612 (void) ioctl(0, KDSIGACCEPT, SIGWINCH);
2613 #endif
2614
2615 /*
2616 * Ignore all signals.
2617 */
2618 for(f = 1; f <= NSIG; f++)
2619 SETSIG(sa, f, SIG_IGN, SA_RESTART);
2620 }
2621
2622 SETSIG(sa, SIGALRM, signal_handler, 0);
2623 SETSIG(sa, SIGHUP, signal_handler, 0);
2624 SETSIG(sa, SIGINT, signal_handler, 0);
2625 SETSIG(sa, SIGCHLD, chld_handler, SA_RESTART);
2626 SETSIG(sa, SIGPWR, signal_handler, 0);
2627 SETSIG(sa, SIGWINCH, signal_handler, 0);
2628 SETSIG(sa, SIGUSR1, signal_handler, 0);
2629 SETSIG(sa, SIGSTOP, stop_handler, SA_RESTART);
2630 SETSIG(sa, SIGTSTP, stop_handler, SA_RESTART);
2631 SETSIG(sa, SIGCONT, cont_handler, SA_RESTART);
2632 SETSIG(sa, SIGSEGV, (void (*)(int))segv_handler, SA_RESTART);
2633
2634 console_init();
2635
2636 if (!reload) {
2637 int fd;
2638
2639 /* Close whatever files are open, and reset the console. */
2640 close(0);
2641 close(1);
2642 close(2);
2643 console_stty();
2644 setsid();
2645
2646 /*
2647 * Set default PATH variable.
2648 */
2649 setenv("PATH", PATH_DEFAULT, 1 /* Overwrite */);
2650
2651 /*
2652 * Initialize /var/run/utmp (only works if /var is on
2653 * root and mounted rw)
2654 */
2655 if ((fd = open(UTMP_FILE, O_WRONLY|O_CREAT|O_TRUNC, 0644)) >= 0)
2656 close(fd);
2657
2658 /*
2659 * Say hello to the world
2660 */
2661 initlog(L_CO, bootmsg, "booting");
2662
2663 /*
2664 * See if we have to start an emergency shell.
2665 */
2666 if (emerg_shell) {
2667 pid_t rc;
2668 SETSIG(sa, SIGCHLD, SIG_DFL, SA_RESTART);
2669 if (spawn(&ch_emerg, &f) > 0) {
2670 while((rc = wait(&st)) != f)
2671 if (rc < 0 && errno == ECHILD)
2672 break;
2673 }
2674 SETSIG(sa, SIGCHLD, chld_handler, SA_RESTART);
2675 }
2676
2677 /*
2678 * Start normal boot procedure.
2679 */
2680 runlevel = '#';
2681 read_inittab();
2682
2683 } else {
2684 /*
2685 * Restart: unblock signals and let the show go on
2686 */
2687 initlog(L_CO, bootmsg, "reloading");
2688 sigfillset(&sgt);
2689 sigprocmask(SIG_UNBLOCK, &sgt, NULL);
2690
2691 /*
2692 * Set default PATH variable.
2693 */
2694 setenv("PATH", PATH_DEFAULT, 0 /* Don't overwrite */);
2695 }
2696 start_if_needed();
2697
2698 while(1) {
2699
2700 /* See if we need to make the boot transitions. */
2701 boot_transitions();
2702 INITDBG(L_VB, "init_main: waiting..");
2703
2704 /* Check if there are processes to be waited on. */
2705 for(ch = family; ch; ch = ch->next)
2706 if ((ch->flags & RUNNING) && ch->action != BOOT) break;
2707
2708 #if CHANGE_WAIT
2709 /* Wait until we get hit by some signal. */
2710 while (ch != NULL && got_signals == 0) {
2711 if (ISMEMBER(got_signals, SIGHUP)) {
2712 /* See if there are processes to be waited on. */
2713 for(ch = family; ch; ch = ch->next)
2714 if (ch->flags & WAITING) break;
2715 }
2716 if (ch != NULL) check_init_fifo();
2717 }
2718 #else /* CHANGE_WAIT */
2719 if (ch != NULL && got_signals == 0) check_init_fifo();
2720 #endif /* CHANGE_WAIT */
2721
2722 /* Check the 'failing' flags */
2723 fail_check();
2724
2725 /* Process any signals. */
2726 process_signals();
2727
2728 /* See what we need to start up (again) */
2729 start_if_needed();
2730 }
2731 /*NOTREACHED*/
2732 }
2733
2734 /*
2735 * Tell the user about the syntax we expect.
2736 */
2737 static
2738 void usage(char *s)
2739 {
2740 fprintf(stderr, "Usage: %s {-e VAR[=VAL] | [-t SECONDS] {0|1|2|3|4|5|6|S|s|Q|q|A|a|B|b|C|c|U|u}}\n", s);
2741 exit(1);
2742 }
2743
2744 static
2745 int telinit(char *progname, int argc, char **argv)
2746 {
2747 #ifdef TELINIT_USES_INITLVL
2748 FILE *fp;
2749 #endif
2750 struct init_request request;
2751 struct sigaction sa;
2752 int f, fd, l;
2753 char *env = NULL;
2754
2755 memset(&request, 0, sizeof(request));
2756 request.magic = INIT_MAGIC;
2757
2758 while ((f = getopt(argc, argv, "t:e:")) != EOF) switch(f) {
2759 case 't':
2760 sltime = atoi(optarg);
2761 break;
2762 case 'e':
2763 if (env == NULL)
2764 env = request.i.data;
2765 l = strlen(optarg);
2766 if (env + l + 2 > request.i.data + sizeof(request.i.data)) {
2767 fprintf(stderr, "%s: -e option data "
2768 "too large\n", progname);
2769 exit(1);
2770 }
2771 memcpy(env, optarg, l);
2772 env += l;
2773 *env++ = 0;
2774 break;
2775 default:
2776 usage(progname);
2777 break;
2778 }
2779
2780 if (env) *env++ = 0;
2781
2782 if (env) {
2783 if (argc != optind)
2784 usage(progname);
2785 request.cmd = INIT_CMD_SETENV;
2786 } else {
2787 if (argc - optind != 1 || strlen(argv[optind]) != 1)
2788 usage(progname);
2789 if (!strchr("0123456789SsQqAaBbCcUu", argv[optind][0]))
2790 usage(progname);
2791 request.cmd = INIT_CMD_RUNLVL;
2792 request.runlevel = argv[optind][0];
2793 request.sleeptime = sltime;
2794 }
2795
2796 /* Change to the root directory. */
2797 chdir("/");
2798
2799 /* Open the fifo and write a command. */
2800 /* Make sure we don't hang on opening /dev/initctl */
2801 SETSIG(sa, SIGALRM, signal_handler, 0);
2802 alarm(3);
2803 if ((fd = open(INIT_FIFO, O_WRONLY)) >= 0) {
2804 ssize_t p = 0;
2805 size_t s = sizeof(request);
2806 void *ptr = &request;
2807
2808 while (s > 0) {
2809 p = write(fd, ptr, s);
2810 if (p < 0) {
2811 if (errno == EINTR || errno == EAGAIN)
2812 continue;
2813 break;
2814 }
2815 ptr += p;
2816 s -= p;
2817 }
2818 close(fd);
2819 alarm(0);
2820 return 0;
2821 }
2822
2823 #ifdef TELINIT_USES_INITLVL
2824 if (request.cmd == INIT_CMD_RUNLVL) {
2825 /* Fallthrough to the old method. */
2826
2827 /* Now write the new runlevel. */
2828 if ((fp = fopen(INITLVL, "w")) == NULL) {
2829 fprintf(stderr, "%s: cannot create %s\n",
2830 progname, INITLVL);
2831 exit(1);
2832 }
2833 fprintf(fp, "%s %d", argv[optind], sltime);
2834 fclose(fp);
2835
2836 /* And tell init about the pending runlevel change. */
2837 if (kill(INITPID, SIGHUP) < 0) perror(progname);
2838
2839 return 0;
2840 }
2841 #endif
2842
2843 fprintf(stderr, "%s: ", progname);
2844 if (ISMEMBER(got_signals, SIGALRM)) {
2845 fprintf(stderr, "timeout opening/writing control channel %s\n",
2846 INIT_FIFO);
2847 } else {
2848 perror(INIT_FIFO);
2849 }
2850 return 1;
2851 }
2852
2853 /*
2854 * Main entry for init and telinit.
2855 */
2856 int main(int argc, char **argv)
2857 {
2858 char *p;
2859 int f;
2860 int isinit;
2861 #ifdef WITH_SELINUX
2862 int enforce = 0;
2863 #endif
2864
2865 /* Get my own name */
2866 if ((p = strrchr(argv[0], '/')) != NULL)
2867 p++;
2868 else
2869 p = argv[0];
2870
2871 /* Common umask */
2872 umask(umask(077) | 022);
2873
2874 /* Quick check */
2875 if (geteuid() != 0) {
2876 fprintf(stderr, "%s: must be superuser.\n", p);
2877 exit(1);
2878 }
2879
2880 /*
2881 * Is this telinit or init ?
2882 */
2883 isinit = (getpid() == 1);
2884 for (f = 1; f < argc; f++) {
2885 if (!strcmp(argv[f], "-i") || !strcmp(argv[f], "--init")) {
2886 isinit = 1;
2887 break;
2888 }
2889 }
2890 if (!isinit) exit(telinit(p, argc, argv));
2891
2892 /*
2893 * Check for re-exec
2894 */
2895 if (check_pipe(STATE_PIPE)) {
2896
2897 receive_state(STATE_PIPE);
2898
2899 myname = istrdup(argv[0]);
2900 argv0 = argv[0];
2901 maxproclen = 0;
2902 for (f = 0; f < argc; f++)
2903 maxproclen += strlen(argv[f]) + 1;
2904 reload = 1;
2905 setproctitle("init [%c]", (int)runlevel);
2906
2907 init_main();
2908 }
2909
2910 /* Check command line arguments */
2911 maxproclen = strlen(argv[0]) + 1;
2912 for(f = 1; f < argc; f++) {
2913 if (!strcmp(argv[f], "single") || !strcmp(argv[f], "-s"))
2914 dfl_level = 'S';
2915 else if (!strcmp(argv[f], "-a") || !strcmp(argv[f], "auto"))
2916 putenv("AUTOBOOT=YES");
2917 else if (!strcmp(argv[f], "-b") || !strcmp(argv[f],"emergency"))
2918 emerg_shell = 1;
2919 else if (!strcmp(argv[f], "-z")) {
2920 /* Ignore -z xxx */
2921 if (argv[f + 1]) f++;
2922 } else if (strchr("0123456789sS", argv[f][0])
2923 && strlen(argv[f]) == 1)
2924 dfl_level = argv[f][0];
2925 /* "init u" in the very beginning makes no sense */
2926 if (dfl_level == 's') dfl_level = 'S';
2927 maxproclen += strlen(argv[f]) + 1;
2928 }
2929
2930 #ifdef WITH_SELINUX
2931 if (getenv("SELINUX_INIT") == NULL) {
2932 if (is_selinux_enabled() != 1) {
2933 if (selinux_init_load_policy(&enforce) == 0) {
2934 putenv("SELINUX_INIT=YES");
2935 execv(myname, argv);
2936 } else {
2937 if (enforce > 0) {
2938 /* SELinux in enforcing mode but load_policy failed */
2939 /* At this point, we probably can't open /dev/console, so log() won't work */
2940 fprintf(stderr,"Unable to load SELinux Policy. Machine is in enforcing mode. Halting now.\n");
2941 exit(1);
2942 }
2943 }
2944 }
2945 }
2946 #endif
2947 /* Start booting. */
2948 argv0 = argv[0];
2949 argv[1] = NULL;
2950 setproctitle("init boot");
2951 init_main();
2952
2953 /*NOTREACHED*/
2954 return 0;
2955 }