1/*- 2 * Copyright (c) 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Donn Seeley at Berkeley Software Design, Inc. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 4. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33#ifndef lint 34static const char copyright[] = 35"@(#) Copyright (c) 1991, 1993\n\ 36 The Regents of the University of California. All rights reserved.\n"; 37#endif /* not lint */ 38 39#ifndef lint 40#if 0 41static char sccsid[] = "@(#)init.c 8.1 (Berkeley) 7/15/93"; 42#endif 43static const char rcsid[] = 44 "$FreeBSD$"; 45#endif /* not lint */ 46 47#include <sys/param.h> 48#include <sys/ioctl.h> 49#include <sys/mount.h> 50#include <sys/sysctl.h> 51#include <sys/wait.h> 52#include <sys/stat.h> 53#include <sys/uio.h> 54 55#include <db.h> 56#include <errno.h> 57#include <fcntl.h> 58#include <kenv.h> 59#include <libutil.h> 60#include <paths.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 <utmpx.h> 70#include <sys/reboot.h> 71#include <err.h> 72 73#include <stdarg.h> 74 75#ifdef SECURE 76#include <pwd.h> 77#endif 78 79#ifdef LOGIN_CAP 80#include <login_cap.h> 81#endif 82 83#include "pathnames.h" 84 85/* 86 * Sleep times; used to prevent thrashing. 87 */ 88#define GETTY_SPACING 5 /* N secs minimum getty spacing */ 89#define GETTY_SLEEP 30 /* sleep N secs after spacing problem */ 90#define GETTY_NSPACE 3 /* max. spacing count to bring reaction */ 91#define WINDOW_WAIT 3 /* wait N secs after starting window */ 92#define STALL_TIMEOUT 30 /* wait N secs after warning */ 93#define DEATH_WATCH 10 /* wait N secs for procs to die */ 94#define DEATH_SCRIPT 120 /* wait for 2min for /etc/rc.shutdown */ 95#define RESOURCE_RC "daemon" 96#define RESOURCE_WINDOW "default" 97#define RESOURCE_GETTY "default" 98 99static void handle(sig_t, ...); 100static void delset(sigset_t *, ...); 101 102static void stall(const char *, ...) __printflike(1, 2); 103static void warning(const char *, ...) __printflike(1, 2); 104static void emergency(const char *, ...) __printflike(1, 2); 105static void disaster(int); 106static void badsys(int); 107static int runshutdown(void); 108static char *strk(char *); 109 110/* 111 * We really need a recursive typedef... 112 * The following at least guarantees that the return type of (*state_t)() 113 * is sufficiently wide to hold a function pointer. 114 */ 115typedef long (*state_func_t)(void); 116typedef state_func_t (*state_t)(void); 117 118static state_func_t single_user(void); 119static state_func_t runcom(void); 120static state_func_t read_ttys(void); 121static state_func_t multi_user(void); 122static state_func_t clean_ttys(void); 123static state_func_t catatonia(void); 124static state_func_t death(void); 125static state_func_t death_single(void); 126 127static state_func_t run_script(const char *); 128 129enum { AUTOBOOT, FASTBOOT } runcom_mode = AUTOBOOT; 130#define FALSE 0 131#define TRUE 1 132 133int Reboot = FALSE; 134int howto = RB_AUTOBOOT; 135 136int devfs; 137 138static void transition(state_t); 139static state_t requested_transition; 140static state_t current_state = death_single; 141 142static void open_console(void); 143static const char *get_shell(void); 144static void write_stderr(const char *message); 145 146typedef struct init_session { 147 int se_index; /* index of entry in ttys file */ 148 pid_t se_process; /* controlling process */ 149 time_t se_started; /* used to avoid thrashing */ 150 int se_flags; /* status of session */ 151#define SE_SHUTDOWN 0x1 /* session won't be restarted */ 152#define SE_PRESENT 0x2 /* session is in /etc/ttys */ 153 int se_nspace; /* spacing count */ 154 char *se_device; /* filename of port */ 155 char *se_getty; /* what to run on that port */ 156 char *se_getty_argv_space; /* pre-parsed argument array space */ 157 char **se_getty_argv; /* pre-parsed argument array */ 158 char *se_window; /* window system (started only once) */ 159 char *se_window_argv_space; /* pre-parsed argument array space */ 160 char **se_window_argv; /* pre-parsed argument array */ 161 char *se_type; /* default terminal type */ 162 struct init_session *se_prev; 163 struct init_session *se_next; 164} session_t; 165 166static void free_session(session_t *); 167static session_t *new_session(session_t *, int, struct ttyent *); 168static session_t *sessions; 169 170static char **construct_argv(char *); 171static void start_window_system(session_t *); 172static void collect_child(pid_t); 173static pid_t start_getty(session_t *); 174static void transition_handler(int); 175static void alrm_handler(int); 176static void setsecuritylevel(int); 177static int getsecuritylevel(void); 178static int setupargv(session_t *, struct ttyent *); 179#ifdef LOGIN_CAP 180static void setprocresources(const char *); 181#endif 182static int clang; 183 184static void clear_session_logs(session_t *); 185 186static int start_session_db(void); 187static void add_session(session_t *); 188static void del_session(session_t *); 189static session_t *find_session(pid_t); 190static DB *session_db; 191 192/* 193 * The mother of all processes. 194 */ 195int 196main(int argc, char *argv[]) 197{ 198 state_t initial_transition = runcom; 199 char kenv_value[PATH_MAX]; 200 int c; 201 struct sigaction sa; 202 sigset_t mask; 203 204 /* Dispose of random users. */ 205 if (getuid() != 0) 206 errx(1, "%s", strerror(EPERM)); 207 208 /* System V users like to reexec init. */ 209 if (getpid() != 1) { 210#ifdef COMPAT_SYSV_INIT 211 /* So give them what they want */ 212 if (argc > 1) { 213 if (strlen(argv[1]) == 1) { 214 char runlevel = *argv[1]; 215 int sig; 216 217 switch (runlevel) { 218 case '0': /* halt + poweroff */ 219 sig = SIGUSR2; 220 break; 221 case '1': /* single-user */ 222 sig = SIGTERM; 223 break; 224 case '6': /* reboot */ 225 sig = SIGINT; 226 break; 227 case 'c': /* block further logins */ 228 sig = SIGTSTP; 229 break; 230 case 'q': /* rescan /etc/ttys */ 231 sig = SIGHUP; 232 break; 233 default: 234 goto invalid; 235 } 236 kill(1, sig); 237 _exit(0); 238 } else 239invalid: 240 errx(1, "invalid run-level ``%s''", argv[1]); 241 } else 242#endif 243 errx(1, "already running"); 244 } 245 /* 246 * Note that this does NOT open a file... 247 * Does 'init' deserve its own facility number? 248 */ 249 openlog("init", LOG_CONS|LOG_ODELAY, LOG_AUTH); 250 251 /* 252 * Create an initial session. 253 */ 254 if (setsid() < 0) 255 warning("initial setsid() failed: %m"); 256 257 /* 258 * Establish an initial user so that programs running 259 * single user do not freak out and die (like passwd). 260 */ 261 if (setlogin("root") < 0) 262 warning("setlogin() failed: %m"); 263 264 /* 265 * This code assumes that we always get arguments through flags, 266 * never through bits set in some random machine register. 267 */ 268 while ((c = getopt(argc, argv, "dsf")) != -1) 269 switch (c) { 270 case 'd': 271 devfs = 1; 272 break; 273 case 's': 274 initial_transition = single_user; 275 break; 276 case 'f': 277 runcom_mode = FASTBOOT; 278 break; 279 default: 280 warning("unrecognized flag '-%c'", c); 281 break; 282 } 283 284 if (optind != argc) 285 warning("ignoring excess arguments"); 286 287 /* 288 * We catch or block signals rather than ignore them, 289 * so that they get reset on exec. 290 */ 291 handle(badsys, SIGSYS, 0); 292 handle(disaster, SIGABRT, SIGFPE, SIGILL, SIGSEGV, SIGBUS, SIGXCPU, 293 SIGXFSZ, 0); 294 handle(transition_handler, SIGHUP, SIGINT, SIGTERM, SIGTSTP, SIGUSR1, 295 SIGUSR2, 0); 296 handle(alrm_handler, SIGALRM, 0); 297 sigfillset(&mask); 298 delset(&mask, SIGABRT, SIGFPE, SIGILL, SIGSEGV, SIGBUS, SIGSYS, 299 SIGXCPU, SIGXFSZ, SIGHUP, SIGINT, SIGTERM, SIGTSTP, SIGALRM, 300 SIGUSR1, SIGUSR2, 0); 301 sigprocmask(SIG_SETMASK, &mask, (sigset_t *) 0); 302 sigemptyset(&sa.sa_mask); 303 sa.sa_flags = 0; 304 sa.sa_handler = SIG_IGN; 305 sigaction(SIGTTIN, &sa, (struct sigaction *)0); 306 sigaction(SIGTTOU, &sa, (struct sigaction *)0); 307 308 /* 309 * Paranoia. 310 */ 311 close(0); 312 close(1); 313 close(2); 314 315 if (kenv(KENV_GET, "init_script", kenv_value, sizeof(kenv_value)) > 0) { 316 state_func_t next_transition; 317 318 if ((next_transition = run_script(kenv_value)) != 0) 319 initial_transition = (state_t) next_transition; 320 } 321 322 if (kenv(KENV_GET, "init_chroot", kenv_value, sizeof(kenv_value)) > 0) { 323 if (chdir(kenv_value) != 0 || chroot(".") != 0) 324 warning("Can't chroot to %s: %m", kenv_value); 325 } 326 327 /* 328 * Additional check if devfs needs to be mounted: 329 * If "/" and "/dev" have the same device number, 330 * then it hasn't been mounted yet. 331 */ 332 if (!devfs) { 333 struct stat stst; 334 dev_t root_devno; 335 336 stat("/", &stst); 337 root_devno = stst.st_dev; 338 if (stat("/dev", &stst) != 0) 339 warning("Can't stat /dev: %m"); 340 else if (stst.st_dev == root_devno) 341 devfs++; 342 } 343 344 if (devfs) { 345 struct iovec iov[4]; 346 char *s; 347 int i; 348 349 char _fstype[] = "fstype"; 350 char _devfs[] = "devfs"; 351 char _fspath[] = "fspath"; 352 char _path_dev[]= _PATH_DEV; 353 354 iov[0].iov_base = _fstype; 355 iov[0].iov_len = sizeof(_fstype); 356 iov[1].iov_base = _devfs; 357 iov[1].iov_len = sizeof(_devfs); 358 iov[2].iov_base = _fspath; 359 iov[2].iov_len = sizeof(_fspath); 360 /* 361 * Try to avoid the trailing slash in _PATH_DEV. 362 * Be *very* defensive. 363 */ 364 s = strdup(_PATH_DEV); 365 if (s != NULL) { 366 i = strlen(s); 367 if (i > 0 && s[i - 1] == '/') 368 s[i - 1] = '\0'; 369 iov[3].iov_base = s; 370 iov[3].iov_len = strlen(s) + 1; 371 } else { 372 iov[3].iov_base = _path_dev; 373 iov[3].iov_len = sizeof(_path_dev); 374 } 375 nmount(iov, 4, 0); 376 if (s != NULL) 377 free(s); 378 } 379 380 /* 381 * Start the state machine. 382 */ 383 transition(initial_transition); 384 385 /* 386 * Should never reach here. 387 */ 388 return 1; 389} 390 391/* 392 * Associate a function with a signal handler. 393 */ 394static void 395handle(sig_t handler, ...) 396{ 397 int sig; 398 struct sigaction sa; 399 sigset_t mask_everything; 400 va_list ap; 401 va_start(ap, handler); 402 403 sa.sa_handler = handler; 404 sigfillset(&mask_everything); 405 406 while ((sig = va_arg(ap, int)) != 0) { 407 sa.sa_mask = mask_everything; 408 /* XXX SA_RESTART? */ 409 sa.sa_flags = sig == SIGCHLD ? SA_NOCLDSTOP : 0; 410 sigaction(sig, &sa, (struct sigaction *) 0); 411 } 412 va_end(ap); 413} 414 415/* 416 * Delete a set of signals from a mask. 417 */ 418static void 419delset(sigset_t *maskp, ...) 420{ 421 int sig; 422 va_list ap; 423 va_start(ap, maskp); 424 425 while ((sig = va_arg(ap, int)) != 0) 426 sigdelset(maskp, sig); 427 va_end(ap); 428} 429 430/* 431 * Log a message and sleep for a while (to give someone an opportunity 432 * to read it and to save log or hardcopy output if the problem is chronic). 433 * NB: should send a message to the session logger to avoid blocking. 434 */ 435static void 436stall(const char *message, ...) 437{ 438 va_list ap; 439 va_start(ap, message); 440 441 vsyslog(LOG_ALERT, message, ap); 442 va_end(ap); 443 sleep(STALL_TIMEOUT); 444} 445 446/* 447 * Like stall(), but doesn't sleep. 448 * If cpp had variadic macros, the two functions could be #defines for another. 449 * NB: should send a message to the session logger to avoid blocking. 450 */ 451static void 452warning(const char *message, ...) 453{ 454 va_list ap; 455 va_start(ap, message); 456 457 vsyslog(LOG_ALERT, message, ap); 458 va_end(ap); 459} 460 461/* 462 * Log an emergency message. 463 * NB: should send a message to the session logger to avoid blocking. 464 */ 465static void 466emergency(const char *message, ...) 467{ 468 va_list ap; 469 va_start(ap, message); 470 471 vsyslog(LOG_EMERG, message, ap); 472 va_end(ap); 473} 474 475/* 476 * Catch a SIGSYS signal. 477 * 478 * These may arise if a system does not support sysctl. 479 * We tolerate up to 25 of these, then throw in the towel. 480 */ 481static void 482badsys(int sig) 483{ 484 static int badcount = 0; 485 486 if (badcount++ < 25) 487 return; 488 disaster(sig); 489} 490 491/* 492 * Catch an unexpected signal. 493 */ 494static void 495disaster(int sig) 496{ 497 498 emergency("fatal signal: %s", 499 (unsigned)sig < NSIG ? sys_siglist[sig] : "unknown signal"); 500 501 sleep(STALL_TIMEOUT); 502 _exit(sig); /* reboot */ 503} 504 505/* 506 * Get the security level of the kernel. 507 */ 508static int 509getsecuritylevel(void) 510{ 511#ifdef KERN_SECURELVL 512 int name[2], curlevel; 513 size_t len; 514 515 name[0] = CTL_KERN; 516 name[1] = KERN_SECURELVL; 517 len = sizeof curlevel; 518 if (sysctl(name, 2, &curlevel, &len, NULL, 0) == -1) { 519 emergency("cannot get kernel security level: %s", 520 strerror(errno)); 521 return (-1); 522 } 523 return (curlevel); 524#else 525 return (-1); 526#endif 527} 528 529/* 530 * Set the security level of the kernel. 531 */ 532static void 533setsecuritylevel(int newlevel) 534{ 535#ifdef KERN_SECURELVL 536 int name[2], curlevel; 537 538 curlevel = getsecuritylevel(); 539 if (newlevel == curlevel) 540 return; 541 name[0] = CTL_KERN; 542 name[1] = KERN_SECURELVL; 543 if (sysctl(name, 2, NULL, NULL, &newlevel, sizeof newlevel) == -1) { 544 emergency( 545 "cannot change kernel security level from %d to %d: %s", 546 curlevel, newlevel, strerror(errno)); 547 return; 548 } 549#ifdef SECURE 550 warning("kernel security level changed from %d to %d", 551 curlevel, newlevel); 552#endif 553#endif 554} 555 556/* 557 * Change states in the finite state machine. 558 * The initial state is passed as an argument. 559 */ 560static void 561transition(state_t s) 562{ 563 564 current_state = s; 565 for (;;) 566 current_state = (state_t) (*current_state)(); 567} 568 569/* 570 * Close out the accounting files for a login session. 571 * NB: should send a message to the session logger to avoid blocking. 572 */ 573static void 574clear_session_logs(session_t *sp __unused) 575{ 576 577 /* 578 * XXX: Use getutxline() and call pututxline() for each entry. 579 * Is this safe to do this here? Is it really required anyway? 580 */ 581} 582 583/* 584 * Start a session and allocate a controlling terminal. 585 * Only called by children of init after forking. 586 */ 587static void 588open_console(void) 589{ 590 int fd; 591 592 /* 593 * Try to open /dev/console. Open the device with O_NONBLOCK to 594 * prevent potential blocking on a carrier. 595 */ 596 revoke(_PATH_CONSOLE); 597 if ((fd = open(_PATH_CONSOLE, O_RDWR | O_NONBLOCK)) != -1) { 598 (void)fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) & ~O_NONBLOCK); 599 if (login_tty(fd) == 0) 600 return; 601 close(fd); 602 } 603 604 /* No luck. Log output to file if possible. */ 605 if ((fd = open(_PATH_DEVNULL, O_RDWR)) == -1) { 606 stall("cannot open null device."); 607 _exit(1); 608 } 609 if (fd != STDIN_FILENO) { 610 dup2(fd, STDIN_FILENO); 611 close(fd); 612 } 613 fd = open(_PATH_INITLOG, O_WRONLY | O_APPEND | O_CREAT, 0644); 614 if (fd == -1) 615 dup2(STDIN_FILENO, STDOUT_FILENO); 616 else if (fd != STDOUT_FILENO) { 617 dup2(fd, STDOUT_FILENO); 618 close(fd); 619 } 620 dup2(STDOUT_FILENO, STDERR_FILENO); 621} 622 623static const char * 624get_shell(void) 625{ 626 static char kenv_value[PATH_MAX]; 627 628 if (kenv(KENV_GET, "init_shell", kenv_value, sizeof(kenv_value)) > 0) 629 return kenv_value; 630 else 631 return _PATH_BSHELL; 632} 633 634static void 635write_stderr(const char *message) 636{ 637 638 write(STDERR_FILENO, message, strlen(message)); 639} 640 641/* 642 * Bring the system up single user. 643 */ 644static state_func_t 645single_user(void) 646{ 647 pid_t pid, wpid; 648 int status; 649 sigset_t mask; 650 const char *shell; 651 char *argv[2]; 652#ifdef SECURE 653 struct ttyent *typ; 654 struct passwd *pp; 655 static const char banner[] = 656 "Enter root password, or ^D to go multi-user\n"; 657 char *clear, *password; 658#endif 659#ifdef DEBUGSHELL 660 char altshell[128]; 661#endif 662 663 if (Reboot) { 664 /* Instead of going single user, let's reboot the machine */ 665 sync(); 666 alarm(2); 667 pause(); 668 reboot(howto); 669 _exit(0); 670 } 671 672 shell = get_shell(); 673 674 if ((pid = fork()) == 0) { 675 /* 676 * Start the single user session. 677 */ 678 open_console(); 679 680#ifdef SECURE 681 /* 682 * Check the root password. 683 * We don't care if the console is 'on' by default; 684 * it's the only tty that can be 'off' and 'secure'. 685 */ 686 typ = getttynam("console"); 687 pp = getpwnam("root"); 688 if (typ && (typ->ty_status & TTY_SECURE) == 0 && 689 pp && *pp->pw_passwd) { 690 write_stderr(banner); 691 for (;;) { 692 clear = getpass("Password:"); 693 if (clear == 0 || *clear == '\0') 694 _exit(0); 695 password = crypt(clear, pp->pw_passwd); 696 bzero(clear, _PASSWORD_LEN); 697 if (strcmp(password, pp->pw_passwd) == 0) 698 break; 699 warning("single-user login failed\n"); 700 } 701 } 702 endttyent(); 703 endpwent(); 704#endif /* SECURE */ 705 706#ifdef DEBUGSHELL 707 { 708 char *cp = altshell; 709 int num; 710 711#define SHREQUEST "Enter full pathname of shell or RETURN for " 712 write_stderr(SHREQUEST); 713 write_stderr(shell); 714 write_stderr(": "); 715 while ((num = read(STDIN_FILENO, cp, 1)) != -1 && 716 num != 0 && *cp != '\n' && cp < &altshell[127]) 717 cp++; 718 *cp = '\0'; 719 if (altshell[0] != '\0') 720 shell = altshell; 721 } 722#endif /* DEBUGSHELL */ 723 724 /* 725 * Unblock signals. 726 * We catch all the interesting ones, 727 * and those are reset to SIG_DFL on exec. 728 */ 729 sigemptyset(&mask); 730 sigprocmask(SIG_SETMASK, &mask, (sigset_t *) 0); 731 732 /* 733 * Fire off a shell. 734 * If the default one doesn't work, try the Bourne shell. 735 */ 736 737 char name[] = "-sh"; 738 739 argv[0] = name; 740 argv[1] = 0; 741 execv(shell, argv); 742 emergency("can't exec %s for single user: %m", shell); 743 execv(_PATH_BSHELL, argv); 744 emergency("can't exec %s for single user: %m", _PATH_BSHELL); 745 sleep(STALL_TIMEOUT); 746 _exit(1); 747 } 748 749 if (pid == -1) { 750 /* 751 * We are seriously hosed. Do our best. 752 */ 753 emergency("can't fork single-user shell, trying again"); 754 while (waitpid(-1, (int *) 0, WNOHANG) > 0) 755 continue; 756 return (state_func_t) single_user; 757 } 758 759 requested_transition = 0; 760 do { 761 if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1) 762 collect_child(wpid); 763 if (wpid == -1) { 764 if (errno == EINTR) 765 continue; 766 warning("wait for single-user shell failed: %m; restarting"); 767 return (state_func_t) single_user; 768 } 769 if (wpid == pid && WIFSTOPPED(status)) { 770 warning("init: shell stopped, restarting\n"); 771 kill(pid, SIGCONT); 772 wpid = -1; 773 } 774 } while (wpid != pid && !requested_transition); 775 776 if (requested_transition) 777 return (state_func_t) requested_transition; 778 779 if (!WIFEXITED(status)) { 780 if (WTERMSIG(status) == SIGKILL) { 781 /* 782 * reboot(8) killed shell? 783 */ 784 warning("single user shell terminated."); 785 sleep(STALL_TIMEOUT); 786 _exit(0); 787 } else { 788 warning("single user shell terminated, restarting"); 789 return (state_func_t) single_user; 790 } 791 } 792 793 runcom_mode = FASTBOOT; 794 return (state_func_t) runcom; 795} 796 797/* 798 * Run the system startup script. 799 */ 800static state_func_t 801runcom(void) 802{ 803 struct utmpx utx; 804 state_func_t next_transition; 805 806 if ((next_transition = run_script(_PATH_RUNCOM)) != 0) 807 return next_transition; 808 809 runcom_mode = AUTOBOOT; /* the default */ 810 /* NB: should send a message to the session logger to avoid blocking. */ 811 utx.ut_type = BOOT_TIME; 812 gettimeofday(&utx.ut_tv, NULL); 813 pututxline(&utx); 814 return (state_func_t) read_ttys; 815} 816 817/* 818 * Run a shell script. 819 * Returns 0 on success, otherwise the next transition to enter: 820 * - single_user if fork/execv/waitpid failed, or if the script 821 * terminated with a signal or exit code != 0. 822 * - death_single if a SIGTERM was delivered to init(8). 823 */ 824static state_func_t 825run_script(const char *script) 826{ 827 pid_t pid, wpid; 828 int status; 829 char *argv[4]; 830 const char *shell; 831 struct sigaction sa; 832 833 shell = get_shell(); 834 835 if ((pid = fork()) == 0) { 836 sigemptyset(&sa.sa_mask); 837 sa.sa_flags = 0; 838 sa.sa_handler = SIG_IGN; 839 sigaction(SIGTSTP, &sa, (struct sigaction *)0); 840 sigaction(SIGHUP, &sa, (struct sigaction *)0); 841 842 open_console(); 843 844 char _sh[] = "sh"; 845 char _autoboot[] = "autoboot"; 846 847 argv[0] = _sh; 848 argv[1] = __DECONST(char *, script); 849 argv[2] = runcom_mode == AUTOBOOT ? _autoboot : 0; 850 argv[3] = 0; 851 852 sigprocmask(SIG_SETMASK, &sa.sa_mask, (sigset_t *) 0); 853 854#ifdef LOGIN_CAP 855 setprocresources(RESOURCE_RC); 856#endif 857 execv(shell, argv); 858 stall("can't exec %s for %s: %m", shell, script); 859 _exit(1); /* force single user mode */ 860 } 861 862 if (pid == -1) { 863 emergency("can't fork for %s on %s: %m", shell, script); 864 while (waitpid(-1, (int *) 0, WNOHANG) > 0) 865 continue; 866 sleep(STALL_TIMEOUT); 867 return (state_func_t) single_user; 868 } 869 870 /* 871 * Copied from single_user(). This is a bit paranoid. 872 */ 873 requested_transition = 0; 874 do { 875 if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1) 876 collect_child(wpid); 877 if (wpid == -1) { 878 if (requested_transition == death_single) 879 return (state_func_t) death_single; 880 if (errno == EINTR) 881 continue; 882 warning("wait for %s on %s failed: %m; going to " 883 "single user mode", shell, script); 884 return (state_func_t) single_user; 885 } 886 if (wpid == pid && WIFSTOPPED(status)) { 887 warning("init: %s on %s stopped, restarting\n", 888 shell, script); 889 kill(pid, SIGCONT); 890 wpid = -1; 891 } 892 } while (wpid != pid); 893 894 if (WIFSIGNALED(status) && WTERMSIG(status) == SIGTERM && 895 requested_transition == catatonia) { 896 /* /etc/rc executed /sbin/reboot; wait for the end quietly */ 897 sigset_t s; 898 899 sigfillset(&s); 900 for (;;) 901 sigsuspend(&s); 902 } 903 904 if (!WIFEXITED(status)) { 905 warning("%s on %s terminated abnormally, going to single " 906 "user mode", shell, script); 907 return (state_func_t) single_user; 908 } 909 910 if (WEXITSTATUS(status)) 911 return (state_func_t) single_user; 912 913 return (state_func_t) 0; 914} 915 916/* 917 * Open the session database. 918 * 919 * NB: We could pass in the size here; is it necessary? 920 */ 921static int 922start_session_db(void) 923{ 924 if (session_db && (*session_db->close)(session_db)) 925 emergency("session database close: %s", strerror(errno)); 926 if ((session_db = dbopen(NULL, O_RDWR, 0, DB_HASH, NULL)) == 0) { 927 emergency("session database open: %s", strerror(errno)); 928 return (1); 929 } 930 return (0); 931 932} 933 934/* 935 * Add a new login session. 936 */ 937static void 938add_session(session_t *sp) 939{ 940 DBT key; 941 DBT data; 942 943 key.data = &sp->se_process; 944 key.size = sizeof sp->se_process; 945 data.data = &sp; 946 data.size = sizeof sp; 947 948 if ((*session_db->put)(session_db, &key, &data, 0)) 949 emergency("insert %d: %s", sp->se_process, strerror(errno)); 950} 951 952/* 953 * Delete an old login session. 954 */ 955static void 956del_session(session_t *sp) 957{ 958 DBT key; 959 960 key.data = &sp->se_process; 961 key.size = sizeof sp->se_process; 962 963 if ((*session_db->del)(session_db, &key, 0)) 964 emergency("delete %d: %s", sp->se_process, strerror(errno)); 965} 966 967/* 968 * Look up a login session by pid. 969 */ 970static session_t * 971find_session(pid_t pid) 972{ 973 DBT key; 974 DBT data; 975 session_t *ret; 976 977 key.data = &pid; 978 key.size = sizeof pid; 979 if ((*session_db->get)(session_db, &key, &data, 0) != 0) 980 return 0; 981 bcopy(data.data, (char *)&ret, sizeof(ret)); 982 return ret; 983} 984 985/* 986 * Construct an argument vector from a command line. 987 */ 988static char ** 989construct_argv(char *command) 990{ 991 int argc = 0; 992 char **argv = (char **) malloc(((strlen(command) + 1) / 2 + 1) 993 * sizeof (char *)); 994 995 if ((argv[argc++] = strk(command)) == 0) { 996 free(argv); 997 return (NULL); 998 } 999 while ((argv[argc++] = strk((char *) 0)) != NULL) 1000 continue; 1001 return argv; 1002} 1003 1004/* 1005 * Deallocate a session descriptor. 1006 */ 1007static void 1008free_session(session_t *sp) 1009{ 1010 free(sp->se_device); 1011 if (sp->se_getty) { 1012 free(sp->se_getty); 1013 free(sp->se_getty_argv_space); 1014 free(sp->se_getty_argv); 1015 } 1016 if (sp->se_window) { 1017 free(sp->se_window); 1018 free(sp->se_window_argv_space); 1019 free(sp->se_window_argv); 1020 } 1021 if (sp->se_type) 1022 free(sp->se_type); 1023 free(sp); 1024} 1025 1026/* 1027 * Allocate a new session descriptor. 1028 * Mark it SE_PRESENT. 1029 */ 1030static session_t * 1031new_session(session_t *sprev, int session_index, struct ttyent *typ) 1032{ 1033 session_t *sp; 1034 int fd; 1035 1036 if ((typ->ty_status & TTY_ON) == 0 || 1037 typ->ty_name == 0 || 1038 typ->ty_getty == 0) 1039 return 0; 1040 1041 sp = (session_t *) calloc(1, sizeof (session_t)); 1042 1043 sp->se_index = session_index; 1044 sp->se_flags |= SE_PRESENT; 1045 1046 sp->se_device = malloc(sizeof(_PATH_DEV) + strlen(typ->ty_name)); 1047 sprintf(sp->se_device, "%s%s", _PATH_DEV, typ->ty_name); 1048 1049 /* 1050 * Attempt to open the device, if we get "device not configured" 1051 * then don't add the device to the session list. 1052 */ 1053 if ((fd = open(sp->se_device, O_RDONLY | O_NONBLOCK, 0)) < 0) { 1054 if (errno == ENXIO) { 1055 free_session(sp); 1056 return (0); 1057 } 1058 } else 1059 close(fd); 1060 1061 if (setupargv(sp, typ) == 0) { 1062 free_session(sp); 1063 return (0); 1064 } 1065 1066 sp->se_next = 0; 1067 if (sprev == 0) { 1068 sessions = sp; 1069 sp->se_prev = 0; 1070 } else { 1071 sprev->se_next = sp; 1072 sp->se_prev = sprev; 1073 } 1074 1075 return sp; 1076} 1077 1078/* 1079 * Calculate getty and if useful window argv vectors. 1080 */ 1081static int 1082setupargv(session_t *sp, struct ttyent *typ) 1083{ 1084 1085 if (sp->se_getty) { 1086 free(sp->se_getty); 1087 free(sp->se_getty_argv_space); 1088 free(sp->se_getty_argv); 1089 } 1090 sp->se_getty = malloc(strlen(typ->ty_getty) + strlen(typ->ty_name) + 2); 1091 sprintf(sp->se_getty, "%s %s", typ->ty_getty, typ->ty_name); 1092 sp->se_getty_argv_space = strdup(sp->se_getty); 1093 sp->se_getty_argv = construct_argv(sp->se_getty_argv_space); 1094 if (sp->se_getty_argv == 0) { 1095 warning("can't parse getty for port %s", sp->se_device); 1096 free(sp->se_getty); 1097 free(sp->se_getty_argv_space); 1098 sp->se_getty = sp->se_getty_argv_space = 0; 1099 return (0); 1100 } 1101 if (sp->se_window) { 1102 free(sp->se_window); 1103 free(sp->se_window_argv_space); 1104 free(sp->se_window_argv); 1105 } 1106 sp->se_window = sp->se_window_argv_space = 0; 1107 sp->se_window_argv = 0; 1108 if (typ->ty_window) { 1109 sp->se_window = strdup(typ->ty_window); 1110 sp->se_window_argv_space = strdup(sp->se_window); 1111 sp->se_window_argv = construct_argv(sp->se_window_argv_space); 1112 if (sp->se_window_argv == 0) { 1113 warning("can't parse window for port %s", 1114 sp->se_device); 1115 free(sp->se_window_argv_space); 1116 free(sp->se_window); 1117 sp->se_window = sp->se_window_argv_space = 0; 1118 return (0); 1119 } 1120 } 1121 if (sp->se_type) 1122 free(sp->se_type); 1123 sp->se_type = typ->ty_type ? strdup(typ->ty_type) : 0; 1124 return (1); 1125} 1126 1127/* 1128 * Walk the list of ttys and create sessions for each active line. 1129 */ 1130static state_func_t 1131read_ttys(void) 1132{ 1133 int session_index = 0; 1134 session_t *sp, *snext; 1135 struct ttyent *typ; 1136 1137 /* 1138 * Destroy any previous session state. 1139 * There shouldn't be any, but just in case... 1140 */ 1141 for (sp = sessions; sp; sp = snext) { 1142 if (sp->se_process) 1143 clear_session_logs(sp); 1144 snext = sp->se_next; 1145 free_session(sp); 1146 } 1147 sessions = 0; 1148 if (start_session_db()) 1149 return (state_func_t) single_user; 1150 1151 /* 1152 * Allocate a session entry for each active port. 1153 * Note that sp starts at 0. 1154 */ 1155 while ((typ = getttyent()) != NULL) 1156 if ((snext = new_session(sp, ++session_index, typ)) != NULL) 1157 sp = snext; 1158 1159 endttyent(); 1160 1161 return (state_func_t) multi_user; 1162} 1163 1164/* 1165 * Start a window system running. 1166 */ 1167static void 1168start_window_system(session_t *sp) 1169{ 1170 pid_t pid; 1171 sigset_t mask; 1172 char term[64], *env[2]; 1173 int status; 1174 1175 if ((pid = fork()) == -1) { 1176 emergency("can't fork for window system on port %s: %m", 1177 sp->se_device); 1178 /* hope that getty fails and we can try again */ 1179 return; 1180 } 1181 if (pid) { 1182 waitpid(-1, &status, 0); 1183 return; 1184 } 1185 1186 /* reparent window process to the init to not make a zombie on exit */ 1187 if ((pid = fork()) == -1) { 1188 emergency("can't fork for window system on port %s: %m", 1189 sp->se_device); 1190 _exit(1); 1191 } 1192 if (pid) 1193 _exit(0); 1194 1195 sigemptyset(&mask); 1196 sigprocmask(SIG_SETMASK, &mask, (sigset_t *) 0); 1197 1198 if (setsid() < 0) 1199 emergency("setsid failed (window) %m"); 1200 1201#ifdef LOGIN_CAP 1202 setprocresources(RESOURCE_WINDOW); 1203#endif 1204 if (sp->se_type) { 1205 /* Don't use malloc after fork */ 1206 strcpy(term, "TERM="); 1207 strncat(term, sp->se_type, sizeof(term) - 6); 1208 env[0] = term; 1209 env[1] = 0; 1210 } 1211 else 1212 env[0] = 0; 1213 execve(sp->se_window_argv[0], sp->se_window_argv, env); 1214 stall("can't exec window system '%s' for port %s: %m", 1215 sp->se_window_argv[0], sp->se_device); 1216 _exit(1); 1217} 1218 1219/* 1220 * Start a login session running. 1221 */ 1222static pid_t 1223start_getty(session_t *sp) 1224{ 1225 pid_t pid; 1226 sigset_t mask; 1227 time_t current_time = time((time_t *) 0); 1228 int too_quick = 0; 1229 char term[64], *env[2]; 1230 1231 if (current_time >= sp->se_started && 1232 current_time - sp->se_started < GETTY_SPACING) { 1233 if (++sp->se_nspace > GETTY_NSPACE) { 1234 sp->se_nspace = 0; 1235 too_quick = 1; 1236 } 1237 } else 1238 sp->se_nspace = 0; 1239 1240 /* 1241 * fork(), not vfork() -- we can't afford to block. 1242 */ 1243 if ((pid = fork()) == -1) { 1244 emergency("can't fork for getty on port %s: %m", sp->se_device); 1245 return -1; 1246 } 1247 1248 if (pid) 1249 return pid; 1250 1251 if (too_quick) { 1252 warning("getty repeating too quickly on port %s, sleeping %d secs", 1253 sp->se_device, GETTY_SLEEP); 1254 sleep((unsigned) GETTY_SLEEP); 1255 } 1256 1257 if (sp->se_window) { 1258 start_window_system(sp); 1259 sleep(WINDOW_WAIT); 1260 } 1261 1262 sigemptyset(&mask); 1263 sigprocmask(SIG_SETMASK, &mask, (sigset_t *) 0); 1264 1265#ifdef LOGIN_CAP 1266 setprocresources(RESOURCE_GETTY); 1267#endif 1268 if (sp->se_type) { 1269 /* Don't use malloc after fork */ 1270 strcpy(term, "TERM="); 1271 strncat(term, sp->se_type, sizeof(term) - 6); 1272 env[0] = term; 1273 env[1] = 0; 1274 } else 1275 env[0] = 0; 1276 execve(sp->se_getty_argv[0], sp->se_getty_argv, env); 1277 stall("can't exec getty '%s' for port %s: %m", 1278 sp->se_getty_argv[0], sp->se_device); 1279 _exit(1); 1280} 1281 1282/* 1283 * Collect exit status for a child. 1284 * If an exiting login, start a new login running. 1285 */ 1286static void 1287collect_child(pid_t pid) 1288{ 1289 session_t *sp, *sprev, *snext; 1290 1291 if (! sessions) 1292 return; 1293 1294 if (! (sp = find_session(pid))) 1295 return; 1296 1297 clear_session_logs(sp); 1298 del_session(sp); 1299 sp->se_process = 0; 1300 1301 if (sp->se_flags & SE_SHUTDOWN) { 1302 if ((sprev = sp->se_prev) != NULL) 1303 sprev->se_next = sp->se_next; 1304 else 1305 sessions = sp->se_next; 1306 if ((snext = sp->se_next) != NULL) 1307 snext->se_prev = sp->se_prev; 1308 free_session(sp); 1309 return; 1310 } 1311 1312 if ((pid = start_getty(sp)) == -1) { 1313 /* serious trouble */ 1314 requested_transition = clean_ttys; 1315 return; 1316 } 1317 1318 sp->se_process = pid; 1319 sp->se_started = time((time_t *) 0); 1320 add_session(sp); 1321} 1322 1323/* 1324 * Catch a signal and request a state transition. 1325 */ 1326static void 1327transition_handler(int sig) 1328{ 1329 1330 switch (sig) { 1331 case SIGHUP: 1332 if (current_state == read_ttys || current_state == multi_user || 1333 current_state == clean_ttys || current_state == catatonia) 1334 requested_transition = clean_ttys; 1335 break; 1336 case SIGUSR2: 1337 howto = RB_POWEROFF; 1338 case SIGUSR1: 1339 howto |= RB_HALT; 1340 case SIGINT: 1341 Reboot = TRUE; 1342 case SIGTERM: 1343 if (current_state == read_ttys || current_state == multi_user || 1344 current_state == clean_ttys || current_state == catatonia) 1345 requested_transition = death; 1346 else 1347 requested_transition = death_single; 1348 break; 1349 case SIGTSTP: 1350 if (current_state == runcom || current_state == read_ttys || 1351 current_state == clean_ttys || 1352 current_state == multi_user || current_state == catatonia) 1353 requested_transition = catatonia; 1354 break; 1355 default: 1356 requested_transition = 0; 1357 break; 1358 } 1359} 1360 1361/* 1362 * Take the system multiuser. 1363 */ 1364static state_func_t 1365multi_user(void) 1366{ 1367 pid_t pid; 1368 session_t *sp; 1369 1370 requested_transition = 0; 1371 1372 /* 1373 * If the administrator has not set the security level to -1 1374 * to indicate that the kernel should not run multiuser in secure 1375 * mode, and the run script has not set a higher level of security 1376 * than level 1, then put the kernel into secure mode. 1377 */ 1378 if (getsecuritylevel() == 0) 1379 setsecuritylevel(1); 1380 1381 for (sp = sessions; sp; sp = sp->se_next) { 1382 if (sp->se_process) 1383 continue; 1384 if ((pid = start_getty(sp)) == -1) { 1385 /* serious trouble */ 1386 requested_transition = clean_ttys; 1387 break; 1388 } 1389 sp->se_process = pid; 1390 sp->se_started = time((time_t *) 0); 1391 add_session(sp); 1392 } 1393 1394 while (!requested_transition) 1395 if ((pid = waitpid(-1, (int *) 0, 0)) != -1) 1396 collect_child(pid); 1397 1398 return (state_func_t) requested_transition; 1399} 1400 1401/* 1402 * This is an (n*2)+(n^2) algorithm. We hope it isn't run often... 1403 */ 1404static state_func_t 1405clean_ttys(void) 1406{ 1407 session_t *sp, *sprev; 1408 struct ttyent *typ; 1409 int session_index = 0; 1410 int devlen; 1411 char *old_getty, *old_window, *old_type; 1412 1413 /* 1414 * mark all sessions for death, (!SE_PRESENT) 1415 * as we find or create new ones they'll be marked as keepers, 1416 * we'll later nuke all the ones not found in /etc/ttys 1417 */ 1418 for (sp = sessions; sp != NULL; sp = sp->se_next) 1419 sp->se_flags &= ~SE_PRESENT; 1420 1421 devlen = sizeof(_PATH_DEV) - 1; 1422 while ((typ = getttyent()) != NULL) { 1423 ++session_index; 1424 1425 for (sprev = 0, sp = sessions; sp; sprev = sp, sp = sp->se_next) 1426 if (strcmp(typ->ty_name, sp->se_device + devlen) == 0) 1427 break; 1428 1429 if (sp) { 1430 /* we want this one to live */ 1431 sp->se_flags |= SE_PRESENT; 1432 if (sp->se_index != session_index) { 1433 warning("port %s changed utmp index from %d to %d", 1434 sp->se_device, sp->se_index, 1435 session_index); 1436 sp->se_index = session_index; 1437 } 1438 if ((typ->ty_status & TTY_ON) == 0 || 1439 typ->ty_getty == 0) { 1440 sp->se_flags |= SE_SHUTDOWN; 1441 kill(sp->se_process, SIGHUP); 1442 continue; 1443 } 1444 sp->se_flags &= ~SE_SHUTDOWN; 1445 old_getty = sp->se_getty ? strdup(sp->se_getty) : 0; 1446 old_window = sp->se_window ? strdup(sp->se_window) : 0; 1447 old_type = sp->se_type ? strdup(sp->se_type) : 0; 1448 if (setupargv(sp, typ) == 0) { 1449 warning("can't parse getty for port %s", 1450 sp->se_device); 1451 sp->se_flags |= SE_SHUTDOWN; 1452 kill(sp->se_process, SIGHUP); 1453 } 1454 else if ( !old_getty 1455 || (!old_type && sp->se_type) 1456 || (old_type && !sp->se_type) 1457 || (!old_window && sp->se_window) 1458 || (old_window && !sp->se_window) 1459 || (strcmp(old_getty, sp->se_getty) != 0) 1460 || (old_window && strcmp(old_window, sp->se_window) != 0) 1461 || (old_type && strcmp(old_type, sp->se_type) != 0) 1462 ) { 1463 /* Don't set SE_SHUTDOWN here */ 1464 sp->se_nspace = 0; 1465 sp->se_started = 0; 1466 kill(sp->se_process, SIGHUP); 1467 } 1468 if (old_getty) 1469 free(old_getty); 1470 if (old_window) 1471 free(old_window); 1472 if (old_type) 1473 free(old_type); 1474 continue; 1475 } 1476 1477 new_session(sprev, session_index, typ); 1478 } 1479 1480 endttyent(); 1481 1482 /* 1483 * sweep through and kill all deleted sessions 1484 * ones who's /etc/ttys line was deleted (SE_PRESENT unset) 1485 */ 1486 for (sp = sessions; sp != NULL; sp = sp->se_next) { 1487 if ((sp->se_flags & SE_PRESENT) == 0) { 1488 sp->se_flags |= SE_SHUTDOWN; 1489 kill(sp->se_process, SIGHUP); 1490 } 1491 } 1492 1493 return (state_func_t) multi_user; 1494} 1495 1496/* 1497 * Block further logins. 1498 */ 1499static state_func_t 1500catatonia(void) 1501{ 1502 session_t *sp; 1503 1504 for (sp = sessions; sp; sp = sp->se_next) 1505 sp->se_flags |= SE_SHUTDOWN; 1506 1507 return (state_func_t) multi_user; 1508} 1509 1510/* 1511 * Note SIGALRM. 1512 */ 1513static void 1514alrm_handler(int sig) 1515{ 1516 1517 (void)sig; 1518 clang = 1; 1519} 1520 1521/* 1522 * Bring the system down to single user. 1523 */ 1524static state_func_t 1525death(void) 1526{ 1527 struct utmpx utx; 1528 session_t *sp; 1529 1530 /* NB: should send a message to the session logger to avoid blocking. */ 1531 utx.ut_type = SHUTDOWN_TIME; 1532 gettimeofday(&utx.ut_tv, NULL); 1533 pututxline(&utx); 1534 1535 /* 1536 * Also revoke the TTY here. Because runshutdown() may reopen 1537 * the TTY whose getty we're killing here, there is no guarantee 1538 * runshutdown() will perform the initial open() call, causing 1539 * the terminal attributes to be misconfigured. 1540 */ 1541 for (sp = sessions; sp; sp = sp->se_next) { 1542 sp->se_flags |= SE_SHUTDOWN; 1543 kill(sp->se_process, SIGHUP); 1544 revoke(sp->se_device); 1545 } 1546 1547 /* Try to run the rc.shutdown script within a period of time */ 1548 runshutdown(); 1549 1550 return (state_func_t) death_single; 1551} 1552 1553/* 1554 * Do what is necessary to reinitialize single user mode or reboot 1555 * from an incomplete state. 1556 */ 1557static state_func_t 1558death_single(void) 1559{ 1560 int i; 1561 pid_t pid; 1562 static const int death_sigs[2] = { SIGTERM, SIGKILL }; 1563 1564 revoke(_PATH_CONSOLE); 1565 1566 for (i = 0; i < 2; ++i) { 1567 if (kill(-1, death_sigs[i]) == -1 && errno == ESRCH) 1568 return (state_func_t) single_user; 1569 1570 clang = 0; 1571 alarm(DEATH_WATCH); 1572 do 1573 if ((pid = waitpid(-1, (int *)0, 0)) != -1) 1574 collect_child(pid); 1575 while (clang == 0 && errno != ECHILD); 1576 1577 if (errno == ECHILD) 1578 return (state_func_t) single_user; 1579 } 1580 1581 warning("some processes would not die; ps axl advised"); 1582 1583 return (state_func_t) single_user; 1584} 1585 1586/* 1587 * Run the system shutdown script. 1588 * 1589 * Exit codes: XXX I should document more 1590 * -2 shutdown script terminated abnormally 1591 * -1 fatal error - can't run script 1592 * 0 good. 1593 * >0 some error (exit code) 1594 */ 1595static int 1596runshutdown(void) 1597{ 1598 pid_t pid, wpid; 1599 int status; 1600 int shutdowntimeout; 1601 size_t len; 1602 char *argv[4]; 1603 const char *shell; 1604 struct sigaction sa; 1605 struct stat sb; 1606 1607 /* 1608 * rc.shutdown is optional, so to prevent any unnecessary 1609 * complaints from the shell we simply don't run it if the 1610 * file does not exist. If the stat() here fails for other 1611 * reasons, we'll let the shell complain. 1612 */ 1613 if (stat(_PATH_RUNDOWN, &sb) == -1 && errno == ENOENT) 1614 return 0; 1615 1616 shell = get_shell(); 1617 1618 if ((pid = fork()) == 0) { 1619 sigemptyset(&sa.sa_mask); 1620 sa.sa_flags = 0; 1621 sa.sa_handler = SIG_IGN; 1622 sigaction(SIGTSTP, &sa, (struct sigaction *)0); 1623 sigaction(SIGHUP, &sa, (struct sigaction *)0); 1624 1625 open_console(); 1626 1627 char _sh[] = "sh"; 1628 char _reboot[] = "reboot"; 1629 char _single[] = "single"; 1630 char _path_rundown[] = _PATH_RUNDOWN; 1631 1632 argv[0] = _sh; 1633 argv[1] = _path_rundown; 1634 argv[2] = Reboot ? _reboot : _single; 1635 argv[3] = 0; 1636 1637 sigprocmask(SIG_SETMASK, &sa.sa_mask, (sigset_t *) 0); 1638 1639#ifdef LOGIN_CAP 1640 setprocresources(RESOURCE_RC); 1641#endif 1642 execv(shell, argv); 1643 warning("can't exec %s for %s: %m", shell, _PATH_RUNDOWN); 1644 _exit(1); /* force single user mode */ 1645 } 1646 1647 if (pid == -1) { 1648 emergency("can't fork for %s on %s: %m", shell, _PATH_RUNDOWN); 1649 while (waitpid(-1, (int *) 0, WNOHANG) > 0) 1650 continue; 1651 sleep(STALL_TIMEOUT); 1652 return -1; 1653 } 1654 1655 len = sizeof(shutdowntimeout); 1656 if (sysctlbyname("kern.init_shutdown_timeout", &shutdowntimeout, &len, 1657 NULL, 0) == -1 || shutdowntimeout < 2) 1658 shutdowntimeout = DEATH_SCRIPT; 1659 alarm(shutdowntimeout); 1660 clang = 0; 1661 /* 1662 * Copied from single_user(). This is a bit paranoid. 1663 * Use the same ALRM handler. 1664 */ 1665 do { 1666 if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1) 1667 collect_child(wpid); 1668 if (clang == 1) { 1669 /* we were waiting for the sub-shell */ 1670 kill(wpid, SIGTERM); 1671 warning("timeout expired for %s on %s: %m; going to " 1672 "single user mode", shell, _PATH_RUNDOWN); 1673 return -1; 1674 } 1675 if (wpid == -1) { 1676 if (errno == EINTR) 1677 continue; 1678 warning("wait for %s on %s failed: %m; going to " 1679 "single user mode", shell, _PATH_RUNDOWN); 1680 return -1; 1681 } 1682 if (wpid == pid && WIFSTOPPED(status)) { 1683 warning("init: %s on %s stopped, restarting\n", 1684 shell, _PATH_RUNDOWN); 1685 kill(pid, SIGCONT); 1686 wpid = -1; 1687 } 1688 } while (wpid != pid && !clang); 1689 1690 /* Turn off the alarm */ 1691 alarm(0); 1692 1693 if (WIFSIGNALED(status) && WTERMSIG(status) == SIGTERM && 1694 requested_transition == catatonia) { 1695 /* 1696 * /etc/rc.shutdown executed /sbin/reboot; 1697 * wait for the end quietly 1698 */ 1699 sigset_t s; 1700 1701 sigfillset(&s); 1702 for (;;) 1703 sigsuspend(&s); 1704 } 1705 1706 if (!WIFEXITED(status)) { 1707 warning("%s on %s terminated abnormally, going to " 1708 "single user mode", shell, _PATH_RUNDOWN); 1709 return -2; 1710 } 1711 1712 if ((status = WEXITSTATUS(status)) != 0) 1713 warning("%s returned status %d", _PATH_RUNDOWN, status); 1714 1715 return status; 1716} 1717 1718static char * 1719strk(char *p) 1720{ 1721 static char *t; 1722 char *q; 1723 int c; 1724 1725 if (p) 1726 t = p; 1727 if (!t) 1728 return 0; 1729 1730 c = *t; 1731 while (c == ' ' || c == '\t' ) 1732 c = *++t; 1733 if (!c) { 1734 t = 0; 1735 return 0; 1736 } 1737 q = t; 1738 if (c == '\'') { 1739 c = *++t; 1740 q = t; 1741 while (c && c != '\'') 1742 c = *++t; 1743 if (!c) /* unterminated string */ 1744 q = t = 0; 1745 else 1746 *t++ = 0; 1747 } else { 1748 while (c && c != ' ' && c != '\t' ) 1749 c = *++t; 1750 *t++ = 0; 1751 if (!c) 1752 t = 0; 1753 } 1754 return q; 1755} 1756 1757#ifdef LOGIN_CAP 1758static void 1759setprocresources(const char *cname) 1760{ 1761 login_cap_t *lc; 1762 if ((lc = login_getclassbyname(cname, NULL)) != NULL) { 1763 setusercontext(lc, (struct passwd*)NULL, 0, 1764 LOGIN_SETPRIORITY | LOGIN_SETRESOURCES); 1765 login_close(lc); 1766 } 1767} 1768#endif 1769