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