init.c revision 288446
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: head/sbin/init/init.c 288446 2015-10-01 10:52:26Z cperciva $"; 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 98static void handle(sig_t, ...); 99static void delset(sigset_t *, ...); 100 101static void stall(const char *, ...) __printflike(1, 2); 102static void warning(const char *, ...) __printflike(1, 2); 103static void emergency(const char *, ...) __printflike(1, 2); 104static void disaster(int); 105static void badsys(int); 106static int runshutdown(void); 107static 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 */ 114typedef long (*state_func_t)(void); 115typedef state_func_t (*state_t)(void); 116 117static state_func_t single_user(void); 118static state_func_t runcom(void); 119static state_func_t read_ttys(void); 120static state_func_t multi_user(void); 121static state_func_t clean_ttys(void); 122static state_func_t catatonia(void); 123static state_func_t death(void); 124static state_func_t death_single(void); 125 126static state_func_t run_script(const char *); 127 128static enum { AUTOBOOT, FASTBOOT } runcom_mode = AUTOBOOT; 129#define FALSE 0 130#define TRUE 1 131 132static int Reboot = FALSE; 133static int howto = RB_AUTOBOOT; 134 135static int devfs; 136 137static void transition(state_t); 138static state_t requested_transition; 139static state_t current_state = death_single; 140 141static void open_console(void); 142static const char *get_shell(void); 143static void write_stderr(const char *message); 144 145typedef struct init_session { 146 pid_t se_process; /* controlling process */ 147 time_t se_started; /* used to avoid thrashing */ 148 int se_flags; /* status of session */ 149#define SE_SHUTDOWN 0x1 /* session won't be restarted */ 150#define SE_PRESENT 0x2 /* session is in /etc/ttys */ 151 int se_nspace; /* spacing count */ 152 char *se_device; /* filename of port */ 153 char *se_getty; /* what to run on that port */ 154 char *se_getty_argv_space; /* pre-parsed argument array space */ 155 char **se_getty_argv; /* pre-parsed argument array */ 156 char *se_window; /* window system (started only once) */ 157 char *se_window_argv_space; /* pre-parsed argument array space */ 158 char **se_window_argv; /* pre-parsed argument array */ 159 char *se_type; /* default terminal type */ 160 struct init_session *se_prev; 161 struct init_session *se_next; 162} session_t; 163 164static void free_session(session_t *); 165static session_t *new_session(session_t *, struct ttyent *); 166static session_t *sessions; 167 168static char **construct_argv(char *); 169static void start_window_system(session_t *); 170static void collect_child(pid_t); 171static pid_t start_getty(session_t *); 172static void transition_handler(int); 173static void alrm_handler(int); 174static void setsecuritylevel(int); 175static int getsecuritylevel(void); 176static int setupargv(session_t *, struct ttyent *); 177#ifdef LOGIN_CAP 178static void setprocresources(const char *); 179#endif 180static int clang; 181 182static int start_session_db(void); 183static void add_session(session_t *); 184static void del_session(session_t *); 185static session_t *find_session(pid_t); 186static DB *session_db; 187 188/* 189 * The mother of all processes. 190 */ 191int 192main(int argc, char *argv[]) 193{ 194 state_t initial_transition = runcom; 195 char kenv_value[PATH_MAX]; 196 int c; 197 struct sigaction sa; 198 sigset_t mask; 199 200 /* Dispose of random users. */ 201 if (getuid() != 0) 202 errx(1, "%s", strerror(EPERM)); 203 204 /* System V users like to reexec init. */ 205 if (getpid() != 1) { 206#ifdef COMPAT_SYSV_INIT 207 /* So give them what they want */ 208 if (argc > 1) { 209 if (strlen(argv[1]) == 1) { 210 char runlevel = *argv[1]; 211 int sig; 212 213 switch (runlevel) { 214 case '0': /* halt + poweroff */ 215 sig = SIGUSR2; 216 break; 217 case '1': /* single-user */ 218 sig = SIGTERM; 219 break; 220 case '6': /* reboot */ 221 sig = SIGINT; 222 break; 223 case 'c': /* block further logins */ 224 sig = SIGTSTP; 225 break; 226 case 'q': /* rescan /etc/ttys */ 227 sig = SIGHUP; 228 break; 229 default: 230 goto invalid; 231 } 232 kill(1, sig); 233 _exit(0); 234 } else 235invalid: 236 errx(1, "invalid run-level ``%s''", argv[1]); 237 } else 238#endif 239 errx(1, "already running"); 240 } 241 /* 242 * Note that this does NOT open a file... 243 * Does 'init' deserve its own facility number? 244 */ 245 openlog("init", LOG_CONS, LOG_AUTH); 246 247 /* 248 * Create an initial session. 249 */ 250 if (setsid() < 0) 251 warning("initial setsid() failed: %m"); 252 253 /* 254 * Establish an initial user so that programs running 255 * single user do not freak out and die (like passwd). 256 */ 257 if (setlogin("root") < 0) 258 warning("setlogin() failed: %m"); 259 260 /* 261 * This code assumes that we always get arguments through flags, 262 * never through bits set in some random machine register. 263 */ 264 while ((c = getopt(argc, argv, "dsf")) != -1) 265 switch (c) { 266 case 'd': 267 devfs = 1; 268 break; 269 case 's': 270 initial_transition = single_user; 271 break; 272 case 'f': 273 runcom_mode = FASTBOOT; 274 break; 275 default: 276 warning("unrecognized flag '-%c'", c); 277 break; 278 } 279 280 if (optind != argc) 281 warning("ignoring excess arguments"); 282 283 /* 284 * We catch or block signals rather than ignore them, 285 * so that they get reset on exec. 286 */ 287 handle(badsys, SIGSYS, 0); 288 handle(disaster, SIGABRT, SIGFPE, SIGILL, SIGSEGV, SIGBUS, SIGXCPU, 289 SIGXFSZ, 0); 290 handle(transition_handler, SIGHUP, SIGINT, SIGTERM, SIGTSTP, SIGUSR1, 291 SIGUSR2, 0); 292 handle(alrm_handler, SIGALRM, 0); 293 sigfillset(&mask); 294 delset(&mask, SIGABRT, SIGFPE, SIGILL, SIGSEGV, SIGBUS, SIGSYS, 295 SIGXCPU, SIGXFSZ, SIGHUP, SIGINT, SIGTERM, SIGTSTP, SIGALRM, 296 SIGUSR1, SIGUSR2, 0); 297 sigprocmask(SIG_SETMASK, &mask, (sigset_t *) 0); 298 sigemptyset(&sa.sa_mask); 299 sa.sa_flags = 0; 300 sa.sa_handler = SIG_IGN; 301 sigaction(SIGTTIN, &sa, (struct sigaction *)0); 302 sigaction(SIGTTOU, &sa, (struct sigaction *)0); 303 304 /* 305 * Paranoia. 306 */ 307 close(0); 308 close(1); 309 close(2); 310 311 if (kenv(KENV_GET, "init_script", kenv_value, sizeof(kenv_value)) > 0) { 312 state_func_t next_transition; 313 314 if ((next_transition = run_script(kenv_value)) != 0) 315 initial_transition = (state_t) next_transition; 316 } 317 318 if (kenv(KENV_GET, "init_chroot", kenv_value, sizeof(kenv_value)) > 0) { 319 if (chdir(kenv_value) != 0 || chroot(".") != 0) 320 warning("Can't chroot to %s: %m", kenv_value); 321 } 322 323 /* 324 * Additional check if devfs needs to be mounted: 325 * If "/" and "/dev" have the same device number, 326 * then it hasn't been mounted yet. 327 */ 328 if (!devfs) { 329 struct stat stst; 330 dev_t root_devno; 331 332 stat("/", &stst); 333 root_devno = stst.st_dev; 334 if (stat("/dev", &stst) != 0) 335 warning("Can't stat /dev: %m"); 336 else if (stst.st_dev == root_devno) 337 devfs++; 338 } 339 340 if (devfs) { 341 struct iovec iov[4]; 342 char *s; 343 int i; 344 345 char _fstype[] = "fstype"; 346 char _devfs[] = "devfs"; 347 char _fspath[] = "fspath"; 348 char _path_dev[]= _PATH_DEV; 349 350 iov[0].iov_base = _fstype; 351 iov[0].iov_len = sizeof(_fstype); 352 iov[1].iov_base = _devfs; 353 iov[1].iov_len = sizeof(_devfs); 354 iov[2].iov_base = _fspath; 355 iov[2].iov_len = sizeof(_fspath); 356 /* 357 * Try to avoid the trailing slash in _PATH_DEV. 358 * Be *very* defensive. 359 */ 360 s = strdup(_PATH_DEV); 361 if (s != NULL) { 362 i = strlen(s); 363 if (i > 0 && s[i - 1] == '/') 364 s[i - 1] = '\0'; 365 iov[3].iov_base = s; 366 iov[3].iov_len = strlen(s) + 1; 367 } else { 368 iov[3].iov_base = _path_dev; 369 iov[3].iov_len = sizeof(_path_dev); 370 } 371 nmount(iov, 4, 0); 372 if (s != NULL) 373 free(s); 374 } 375 376 /* 377 * Start the state machine. 378 */ 379 transition(initial_transition); 380 381 /* 382 * Should never reach here. 383 */ 384 return 1; 385} 386 387/* 388 * Associate a function with a signal handler. 389 */ 390static void 391handle(sig_t handler, ...) 392{ 393 int sig; 394 struct sigaction sa; 395 sigset_t mask_everything; 396 va_list ap; 397 va_start(ap, handler); 398 399 sa.sa_handler = handler; 400 sigfillset(&mask_everything); 401 402 while ((sig = va_arg(ap, int)) != 0) { 403 sa.sa_mask = mask_everything; 404 /* XXX SA_RESTART? */ 405 sa.sa_flags = sig == SIGCHLD ? SA_NOCLDSTOP : 0; 406 sigaction(sig, &sa, (struct sigaction *) 0); 407 } 408 va_end(ap); 409} 410 411/* 412 * Delete a set of signals from a mask. 413 */ 414static void 415delset(sigset_t *maskp, ...) 416{ 417 int sig; 418 va_list ap; 419 va_start(ap, maskp); 420 421 while ((sig = va_arg(ap, int)) != 0) 422 sigdelset(maskp, sig); 423 va_end(ap); 424} 425 426/* 427 * Log a message and sleep for a while (to give someone an opportunity 428 * to read it and to save log or hardcopy output if the problem is chronic). 429 * NB: should send a message to the session logger to avoid blocking. 430 */ 431static void 432stall(const char *message, ...) 433{ 434 va_list ap; 435 va_start(ap, message); 436 437 vsyslog(LOG_ALERT, message, ap); 438 va_end(ap); 439 sleep(STALL_TIMEOUT); 440} 441 442/* 443 * Like stall(), but doesn't sleep. 444 * If cpp had variadic macros, the two functions could be #defines for another. 445 * NB: should send a message to the session logger to avoid blocking. 446 */ 447static void 448warning(const char *message, ...) 449{ 450 va_list ap; 451 va_start(ap, message); 452 453 vsyslog(LOG_ALERT, message, ap); 454 va_end(ap); 455} 456 457/* 458 * Log an emergency message. 459 * NB: should send a message to the session logger to avoid blocking. 460 */ 461static void 462emergency(const char *message, ...) 463{ 464 va_list ap; 465 va_start(ap, message); 466 467 vsyslog(LOG_EMERG, message, ap); 468 va_end(ap); 469} 470 471/* 472 * Catch a SIGSYS signal. 473 * 474 * These may arise if a system does not support sysctl. 475 * We tolerate up to 25 of these, then throw in the towel. 476 */ 477static void 478badsys(int sig) 479{ 480 static int badcount = 0; 481 482 if (badcount++ < 25) 483 return; 484 disaster(sig); 485} 486 487/* 488 * Catch an unexpected signal. 489 */ 490static void 491disaster(int sig) 492{ 493 494 emergency("fatal signal: %s", 495 (unsigned)sig < NSIG ? sys_siglist[sig] : "unknown signal"); 496 497 sleep(STALL_TIMEOUT); 498 _exit(sig); /* reboot */ 499} 500 501/* 502 * Get the security level of the kernel. 503 */ 504static int 505getsecuritylevel(void) 506{ 507#ifdef KERN_SECURELVL 508 int name[2], curlevel; 509 size_t len; 510 511 name[0] = CTL_KERN; 512 name[1] = KERN_SECURELVL; 513 len = sizeof curlevel; 514 if (sysctl(name, 2, &curlevel, &len, NULL, 0) == -1) { 515 emergency("cannot get kernel security level: %s", 516 strerror(errno)); 517 return (-1); 518 } 519 return (curlevel); 520#else 521 return (-1); 522#endif 523} 524 525/* 526 * Set the security level of the kernel. 527 */ 528static void 529setsecuritylevel(int newlevel) 530{ 531#ifdef KERN_SECURELVL 532 int name[2], curlevel; 533 534 curlevel = getsecuritylevel(); 535 if (newlevel == curlevel) 536 return; 537 name[0] = CTL_KERN; 538 name[1] = KERN_SECURELVL; 539 if (sysctl(name, 2, NULL, NULL, &newlevel, sizeof newlevel) == -1) { 540 emergency( 541 "cannot change kernel security level from %d to %d: %s", 542 curlevel, newlevel, strerror(errno)); 543 return; 544 } 545#ifdef SECURE 546 warning("kernel security level changed from %d to %d", 547 curlevel, newlevel); 548#endif 549#endif 550} 551 552/* 553 * Change states in the finite state machine. 554 * The initial state is passed as an argument. 555 */ 556static void 557transition(state_t s) 558{ 559 560 current_state = s; 561 for (;;) 562 current_state = (state_t) (*current_state)(); 563} 564 565/* 566 * Start a session and allocate a controlling terminal. 567 * Only called by children of init after forking. 568 */ 569static void 570open_console(void) 571{ 572 int fd; 573 574 /* 575 * Try to open /dev/console. Open the device with O_NONBLOCK to 576 * prevent potential blocking on a carrier. 577 */ 578 revoke(_PATH_CONSOLE); 579 if ((fd = open(_PATH_CONSOLE, O_RDWR | O_NONBLOCK)) != -1) { 580 (void)fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) & ~O_NONBLOCK); 581 if (login_tty(fd) == 0) 582 return; 583 close(fd); 584 } 585 586 /* No luck. Log output to file if possible. */ 587 if ((fd = open(_PATH_DEVNULL, O_RDWR)) == -1) { 588 stall("cannot open null device."); 589 _exit(1); 590 } 591 if (fd != STDIN_FILENO) { 592 dup2(fd, STDIN_FILENO); 593 close(fd); 594 } 595 fd = open(_PATH_INITLOG, O_WRONLY | O_APPEND | O_CREAT, 0644); 596 if (fd == -1) 597 dup2(STDIN_FILENO, STDOUT_FILENO); 598 else if (fd != STDOUT_FILENO) { 599 dup2(fd, STDOUT_FILENO); 600 close(fd); 601 } 602 dup2(STDOUT_FILENO, STDERR_FILENO); 603} 604 605static const char * 606get_shell(void) 607{ 608 static char kenv_value[PATH_MAX]; 609 610 if (kenv(KENV_GET, "init_shell", kenv_value, sizeof(kenv_value)) > 0) 611 return kenv_value; 612 else 613 return _PATH_BSHELL; 614} 615 616static void 617write_stderr(const char *message) 618{ 619 620 write(STDERR_FILENO, message, strlen(message)); 621} 622 623/* 624 * Bring the system up single user. 625 */ 626static state_func_t 627single_user(void) 628{ 629 pid_t pid, wpid; 630 int status; 631 sigset_t mask; 632 const char *shell; 633 char *argv[2]; 634#ifdef SECURE 635 struct ttyent *typ; 636 struct passwd *pp; 637 static const char banner[] = 638 "Enter root password, or ^D to go multi-user\n"; 639 char *clear, *password; 640#endif 641#ifdef DEBUGSHELL 642 char altshell[128]; 643#endif 644 645 if (Reboot) { 646 /* Instead of going single user, let's reboot the machine */ 647 sync(); 648 reboot(howto); 649 _exit(0); 650 } 651 652 shell = get_shell(); 653 654 if ((pid = fork()) == 0) { 655 /* 656 * Start the single user session. 657 */ 658 open_console(); 659 660#ifdef SECURE 661 /* 662 * Check the root password. 663 * We don't care if the console is 'on' by default; 664 * it's the only tty that can be 'off' and 'secure'. 665 */ 666 typ = getttynam("console"); 667 pp = getpwnam("root"); 668 if (typ && (typ->ty_status & TTY_SECURE) == 0 && 669 pp && *pp->pw_passwd) { 670 write_stderr(banner); 671 for (;;) { 672 clear = getpass("Password:"); 673 if (clear == 0 || *clear == '\0') 674 _exit(0); 675 password = crypt(clear, pp->pw_passwd); 676 bzero(clear, _PASSWORD_LEN); 677 if (password == NULL || 678 strcmp(password, pp->pw_passwd) == 0) 679 break; 680 warning("single-user login failed\n"); 681 } 682 } 683 endttyent(); 684 endpwent(); 685#endif /* SECURE */ 686 687#ifdef DEBUGSHELL 688 { 689 char *cp = altshell; 690 int num; 691 692#define SHREQUEST "Enter full pathname of shell or RETURN for " 693 write_stderr(SHREQUEST); 694 write_stderr(shell); 695 write_stderr(": "); 696 while ((num = read(STDIN_FILENO, cp, 1)) != -1 && 697 num != 0 && *cp != '\n' && cp < &altshell[127]) 698 cp++; 699 *cp = '\0'; 700 if (altshell[0] != '\0') 701 shell = altshell; 702 } 703#endif /* DEBUGSHELL */ 704 705 /* 706 * Unblock signals. 707 * We catch all the interesting ones, 708 * and those are reset to SIG_DFL on exec. 709 */ 710 sigemptyset(&mask); 711 sigprocmask(SIG_SETMASK, &mask, (sigset_t *) 0); 712 713 /* 714 * Fire off a shell. 715 * If the default one doesn't work, try the Bourne shell. 716 */ 717 718 char name[] = "-sh"; 719 720 argv[0] = name; 721 argv[1] = 0; 722 execv(shell, argv); 723 emergency("can't exec %s for single user: %m", shell); 724 execv(_PATH_BSHELL, argv); 725 emergency("can't exec %s for single user: %m", _PATH_BSHELL); 726 sleep(STALL_TIMEOUT); 727 _exit(1); 728 } 729 730 if (pid == -1) { 731 /* 732 * We are seriously hosed. Do our best. 733 */ 734 emergency("can't fork single-user shell, trying again"); 735 while (waitpid(-1, (int *) 0, WNOHANG) > 0) 736 continue; 737 return (state_func_t) single_user; 738 } 739 740 requested_transition = 0; 741 do { 742 if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1) 743 collect_child(wpid); 744 if (wpid == -1) { 745 if (errno == EINTR) 746 continue; 747 warning("wait for single-user shell failed: %m; restarting"); 748 return (state_func_t) single_user; 749 } 750 if (wpid == pid && WIFSTOPPED(status)) { 751 warning("init: shell stopped, restarting\n"); 752 kill(pid, SIGCONT); 753 wpid = -1; 754 } 755 } while (wpid != pid && !requested_transition); 756 757 if (requested_transition) 758 return (state_func_t) requested_transition; 759 760 if (!WIFEXITED(status)) { 761 if (WTERMSIG(status) == SIGKILL) { 762 /* 763 * reboot(8) killed shell? 764 */ 765 warning("single user shell terminated."); 766 sleep(STALL_TIMEOUT); 767 _exit(0); 768 } else { 769 warning("single user shell terminated, restarting"); 770 return (state_func_t) single_user; 771 } 772 } 773 774 runcom_mode = FASTBOOT; 775 return (state_func_t) runcom; 776} 777 778/* 779 * Run the system startup script. 780 */ 781static state_func_t 782runcom(void) 783{ 784 state_func_t next_transition; 785 786 if ((next_transition = run_script(_PATH_RUNCOM)) != 0) 787 return next_transition; 788 789 runcom_mode = AUTOBOOT; /* the default */ 790 return (state_func_t) read_ttys; 791} 792 793/* 794 * Run a shell script. 795 * Returns 0 on success, otherwise the next transition to enter: 796 * - single_user if fork/execv/waitpid failed, or if the script 797 * terminated with a signal or exit code != 0. 798 * - death_single if a SIGTERM was delivered to init(8). 799 */ 800static state_func_t 801run_script(const char *script) 802{ 803 pid_t pid, wpid; 804 int status; 805 char *argv[4]; 806 const char *shell; 807 struct sigaction sa; 808 809 shell = get_shell(); 810 811 if ((pid = fork()) == 0) { 812 sigemptyset(&sa.sa_mask); 813 sa.sa_flags = 0; 814 sa.sa_handler = SIG_IGN; 815 sigaction(SIGTSTP, &sa, (struct sigaction *)0); 816 sigaction(SIGHUP, &sa, (struct sigaction *)0); 817 818 open_console(); 819 820 char _sh[] = "sh"; 821 char _autoboot[] = "autoboot"; 822 823 argv[0] = _sh; 824 argv[1] = __DECONST(char *, script); 825 argv[2] = runcom_mode == AUTOBOOT ? _autoboot : 0; 826 argv[3] = 0; 827 828 sigprocmask(SIG_SETMASK, &sa.sa_mask, (sigset_t *) 0); 829 830#ifdef LOGIN_CAP 831 setprocresources(RESOURCE_RC); 832#endif 833 execv(shell, argv); 834 stall("can't exec %s for %s: %m", shell, script); 835 _exit(1); /* force single user mode */ 836 } 837 838 if (pid == -1) { 839 emergency("can't fork for %s on %s: %m", shell, script); 840 while (waitpid(-1, (int *) 0, WNOHANG) > 0) 841 continue; 842 sleep(STALL_TIMEOUT); 843 return (state_func_t) single_user; 844 } 845 846 /* 847 * Copied from single_user(). This is a bit paranoid. 848 */ 849 requested_transition = 0; 850 do { 851 if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1) 852 collect_child(wpid); 853 if (wpid == -1) { 854 if (requested_transition == death_single) 855 return (state_func_t) death_single; 856 if (errno == EINTR) 857 continue; 858 warning("wait for %s on %s failed: %m; going to " 859 "single user mode", shell, script); 860 return (state_func_t) single_user; 861 } 862 if (wpid == pid && WIFSTOPPED(status)) { 863 warning("init: %s on %s stopped, restarting\n", 864 shell, script); 865 kill(pid, SIGCONT); 866 wpid = -1; 867 } 868 } while (wpid != pid); 869 870 if (WIFSIGNALED(status) && WTERMSIG(status) == SIGTERM && 871 requested_transition == catatonia) { 872 /* /etc/rc executed /sbin/reboot; wait for the end quietly */ 873 sigset_t s; 874 875 sigfillset(&s); 876 for (;;) 877 sigsuspend(&s); 878 } 879 880 if (!WIFEXITED(status)) { 881 warning("%s on %s terminated abnormally, going to single " 882 "user mode", shell, script); 883 return (state_func_t) single_user; 884 } 885 886 if (WEXITSTATUS(status)) 887 return (state_func_t) single_user; 888 889 return (state_func_t) 0; 890} 891 892/* 893 * Open the session database. 894 * 895 * NB: We could pass in the size here; is it necessary? 896 */ 897static int 898start_session_db(void) 899{ 900 if (session_db && (*session_db->close)(session_db)) 901 emergency("session database close: %s", strerror(errno)); 902 if ((session_db = dbopen(NULL, O_RDWR, 0, DB_HASH, NULL)) == 0) { 903 emergency("session database open: %s", strerror(errno)); 904 return (1); 905 } 906 return (0); 907 908} 909 910/* 911 * Add a new login session. 912 */ 913static void 914add_session(session_t *sp) 915{ 916 DBT key; 917 DBT data; 918 919 key.data = &sp->se_process; 920 key.size = sizeof sp->se_process; 921 data.data = &sp; 922 data.size = sizeof sp; 923 924 if ((*session_db->put)(session_db, &key, &data, 0)) 925 emergency("insert %d: %s", sp->se_process, strerror(errno)); 926} 927 928/* 929 * Delete an old login session. 930 */ 931static void 932del_session(session_t *sp) 933{ 934 DBT key; 935 936 key.data = &sp->se_process; 937 key.size = sizeof sp->se_process; 938 939 if ((*session_db->del)(session_db, &key, 0)) 940 emergency("delete %d: %s", sp->se_process, strerror(errno)); 941} 942 943/* 944 * Look up a login session by pid. 945 */ 946static session_t * 947find_session(pid_t pid) 948{ 949 DBT key; 950 DBT data; 951 session_t *ret; 952 953 key.data = &pid; 954 key.size = sizeof pid; 955 if ((*session_db->get)(session_db, &key, &data, 0) != 0) 956 return 0; 957 bcopy(data.data, (char *)&ret, sizeof(ret)); 958 return ret; 959} 960 961/* 962 * Construct an argument vector from a command line. 963 */ 964static char ** 965construct_argv(char *command) 966{ 967 int argc = 0; 968 char **argv = (char **) malloc(((strlen(command) + 1) / 2 + 1) 969 * sizeof (char *)); 970 971 if ((argv[argc++] = strk(command)) == 0) { 972 free(argv); 973 return (NULL); 974 } 975 while ((argv[argc++] = strk((char *) 0)) != NULL) 976 continue; 977 return argv; 978} 979 980/* 981 * Deallocate a session descriptor. 982 */ 983static void 984free_session(session_t *sp) 985{ 986 free(sp->se_device); 987 if (sp->se_getty) { 988 free(sp->se_getty); 989 free(sp->se_getty_argv_space); 990 free(sp->se_getty_argv); 991 } 992 if (sp->se_window) { 993 free(sp->se_window); 994 free(sp->se_window_argv_space); 995 free(sp->se_window_argv); 996 } 997 if (sp->se_type) 998 free(sp->se_type); 999 free(sp); 1000} 1001 1002/* 1003 * Allocate a new session descriptor. 1004 * Mark it SE_PRESENT. 1005 */ 1006static session_t * 1007new_session(session_t *sprev, struct ttyent *typ) 1008{ 1009 session_t *sp; 1010 int fd; 1011 1012 if ((typ->ty_status & TTY_ON) == 0 || 1013 typ->ty_name == 0 || 1014 typ->ty_getty == 0) 1015 return 0; 1016 1017 sp = (session_t *) calloc(1, sizeof (session_t)); 1018 1019 sp->se_flags |= SE_PRESENT; 1020 1021 sp->se_device = malloc(sizeof(_PATH_DEV) + strlen(typ->ty_name)); 1022 sprintf(sp->se_device, "%s%s", _PATH_DEV, typ->ty_name); 1023 1024 /* 1025 * Attempt to open the device, if we get "device not configured" 1026 * then don't add the device to the session list. 1027 */ 1028 if ((fd = open(sp->se_device, O_RDONLY | O_NONBLOCK, 0)) < 0) { 1029 if (errno == ENXIO) { 1030 free_session(sp); 1031 return (0); 1032 } 1033 } else 1034 close(fd); 1035 1036 if (setupargv(sp, typ) == 0) { 1037 free_session(sp); 1038 return (0); 1039 } 1040 1041 sp->se_next = 0; 1042 if (sprev == 0) { 1043 sessions = sp; 1044 sp->se_prev = 0; 1045 } else { 1046 sprev->se_next = sp; 1047 sp->se_prev = sprev; 1048 } 1049 1050 return sp; 1051} 1052 1053/* 1054 * Calculate getty and if useful window argv vectors. 1055 */ 1056static int 1057setupargv(session_t *sp, struct ttyent *typ) 1058{ 1059 1060 if (sp->se_getty) { 1061 free(sp->se_getty); 1062 free(sp->se_getty_argv_space); 1063 free(sp->se_getty_argv); 1064 } 1065 sp->se_getty = malloc(strlen(typ->ty_getty) + strlen(typ->ty_name) + 2); 1066 sprintf(sp->se_getty, "%s %s", typ->ty_getty, typ->ty_name); 1067 sp->se_getty_argv_space = strdup(sp->se_getty); 1068 sp->se_getty_argv = construct_argv(sp->se_getty_argv_space); 1069 if (sp->se_getty_argv == 0) { 1070 warning("can't parse getty for port %s", sp->se_device); 1071 free(sp->se_getty); 1072 free(sp->se_getty_argv_space); 1073 sp->se_getty = sp->se_getty_argv_space = 0; 1074 return (0); 1075 } 1076 if (sp->se_window) { 1077 free(sp->se_window); 1078 free(sp->se_window_argv_space); 1079 free(sp->se_window_argv); 1080 } 1081 sp->se_window = sp->se_window_argv_space = 0; 1082 sp->se_window_argv = 0; 1083 if (typ->ty_window) { 1084 sp->se_window = strdup(typ->ty_window); 1085 sp->se_window_argv_space = strdup(sp->se_window); 1086 sp->se_window_argv = construct_argv(sp->se_window_argv_space); 1087 if (sp->se_window_argv == 0) { 1088 warning("can't parse window for port %s", 1089 sp->se_device); 1090 free(sp->se_window_argv_space); 1091 free(sp->se_window); 1092 sp->se_window = sp->se_window_argv_space = 0; 1093 return (0); 1094 } 1095 } 1096 if (sp->se_type) 1097 free(sp->se_type); 1098 sp->se_type = typ->ty_type ? strdup(typ->ty_type) : 0; 1099 return (1); 1100} 1101 1102/* 1103 * Walk the list of ttys and create sessions for each active line. 1104 */ 1105static state_func_t 1106read_ttys(void) 1107{ 1108 session_t *sp, *snext; 1109 struct ttyent *typ; 1110 1111 /* 1112 * Destroy any previous session state. 1113 * There shouldn't be any, but just in case... 1114 */ 1115 for (sp = sessions; sp; sp = snext) { 1116 snext = sp->se_next; 1117 free_session(sp); 1118 } 1119 sessions = 0; 1120 if (start_session_db()) 1121 return (state_func_t) single_user; 1122 1123 /* 1124 * Allocate a session entry for each active port. 1125 * Note that sp starts at 0. 1126 */ 1127 while ((typ = getttyent()) != NULL) 1128 if ((snext = new_session(sp, typ)) != NULL) 1129 sp = snext; 1130 1131 endttyent(); 1132 1133 return (state_func_t) multi_user; 1134} 1135 1136/* 1137 * Start a window system running. 1138 */ 1139static void 1140start_window_system(session_t *sp) 1141{ 1142 pid_t pid; 1143 sigset_t mask; 1144 char term[64], *env[2]; 1145 int status; 1146 1147 if ((pid = fork()) == -1) { 1148 emergency("can't fork for window system on port %s: %m", 1149 sp->se_device); 1150 /* hope that getty fails and we can try again */ 1151 return; 1152 } 1153 if (pid) { 1154 waitpid(-1, &status, 0); 1155 return; 1156 } 1157 1158 /* reparent window process to the init to not make a zombie on exit */ 1159 if ((pid = fork()) == -1) { 1160 emergency("can't fork for window system on port %s: %m", 1161 sp->se_device); 1162 _exit(1); 1163 } 1164 if (pid) 1165 _exit(0); 1166 1167 sigemptyset(&mask); 1168 sigprocmask(SIG_SETMASK, &mask, (sigset_t *) 0); 1169 1170 if (setsid() < 0) 1171 emergency("setsid failed (window) %m"); 1172 1173#ifdef LOGIN_CAP 1174 setprocresources(RESOURCE_WINDOW); 1175#endif 1176 if (sp->se_type) { 1177 /* Don't use malloc after fork */ 1178 strcpy(term, "TERM="); 1179 strncat(term, sp->se_type, sizeof(term) - 6); 1180 env[0] = term; 1181 env[1] = 0; 1182 } 1183 else 1184 env[0] = 0; 1185 execve(sp->se_window_argv[0], sp->se_window_argv, env); 1186 stall("can't exec window system '%s' for port %s: %m", 1187 sp->se_window_argv[0], sp->se_device); 1188 _exit(1); 1189} 1190 1191/* 1192 * Start a login session running. 1193 */ 1194static pid_t 1195start_getty(session_t *sp) 1196{ 1197 pid_t pid; 1198 sigset_t mask; 1199 time_t current_time = time((time_t *) 0); 1200 int too_quick = 0; 1201 char term[64], *env[2]; 1202 1203 if (current_time >= sp->se_started && 1204 current_time - sp->se_started < GETTY_SPACING) { 1205 if (++sp->se_nspace > GETTY_NSPACE) { 1206 sp->se_nspace = 0; 1207 too_quick = 1; 1208 } 1209 } else 1210 sp->se_nspace = 0; 1211 1212 /* 1213 * fork(), not vfork() -- we can't afford to block. 1214 */ 1215 if ((pid = fork()) == -1) { 1216 emergency("can't fork for getty on port %s: %m", sp->se_device); 1217 return -1; 1218 } 1219 1220 if (pid) 1221 return pid; 1222 1223 if (too_quick) { 1224 warning("getty repeating too quickly on port %s, sleeping %d secs", 1225 sp->se_device, GETTY_SLEEP); 1226 sleep((unsigned) GETTY_SLEEP); 1227 } 1228 1229 if (sp->se_window) { 1230 start_window_system(sp); 1231 sleep(WINDOW_WAIT); 1232 } 1233 1234 sigemptyset(&mask); 1235 sigprocmask(SIG_SETMASK, &mask, (sigset_t *) 0); 1236 1237#ifdef LOGIN_CAP 1238 setprocresources(RESOURCE_GETTY); 1239#endif 1240 if (sp->se_type) { 1241 /* Don't use malloc after fork */ 1242 strcpy(term, "TERM="); 1243 strncat(term, sp->se_type, sizeof(term) - 6); 1244 env[0] = term; 1245 env[1] = 0; 1246 } else 1247 env[0] = 0; 1248 execve(sp->se_getty_argv[0], sp->se_getty_argv, env); 1249 stall("can't exec getty '%s' for port %s: %m", 1250 sp->se_getty_argv[0], sp->se_device); 1251 _exit(1); 1252} 1253 1254/* 1255 * Collect exit status for a child. 1256 * If an exiting login, start a new login running. 1257 */ 1258static void 1259collect_child(pid_t pid) 1260{ 1261 session_t *sp, *sprev, *snext; 1262 1263 if (! sessions) 1264 return; 1265 1266 if (! (sp = find_session(pid))) 1267 return; 1268 1269 del_session(sp); 1270 sp->se_process = 0; 1271 1272 if (sp->se_flags & SE_SHUTDOWN) { 1273 if ((sprev = sp->se_prev) != NULL) 1274 sprev->se_next = sp->se_next; 1275 else 1276 sessions = sp->se_next; 1277 if ((snext = sp->se_next) != NULL) 1278 snext->se_prev = sp->se_prev; 1279 free_session(sp); 1280 return; 1281 } 1282 1283 if ((pid = start_getty(sp)) == -1) { 1284 /* serious trouble */ 1285 requested_transition = clean_ttys; 1286 return; 1287 } 1288 1289 sp->se_process = pid; 1290 sp->se_started = time((time_t *) 0); 1291 add_session(sp); 1292} 1293 1294/* 1295 * Catch a signal and request a state transition. 1296 */ 1297static void 1298transition_handler(int sig) 1299{ 1300 1301 switch (sig) { 1302 case SIGHUP: 1303 if (current_state == read_ttys || current_state == multi_user || 1304 current_state == clean_ttys || current_state == catatonia) 1305 requested_transition = clean_ttys; 1306 break; 1307 case SIGUSR2: 1308 howto = RB_POWEROFF; 1309 case SIGUSR1: 1310 howto |= RB_HALT; 1311 case SIGINT: 1312 Reboot = TRUE; 1313 case SIGTERM: 1314 if (current_state == read_ttys || current_state == multi_user || 1315 current_state == clean_ttys || current_state == catatonia) 1316 requested_transition = death; 1317 else 1318 requested_transition = death_single; 1319 break; 1320 case SIGTSTP: 1321 if (current_state == runcom || current_state == read_ttys || 1322 current_state == clean_ttys || 1323 current_state == multi_user || current_state == catatonia) 1324 requested_transition = catatonia; 1325 break; 1326 default: 1327 requested_transition = 0; 1328 break; 1329 } 1330} 1331 1332/* 1333 * Take the system multiuser. 1334 */ 1335static state_func_t 1336multi_user(void) 1337{ 1338 pid_t pid; 1339 session_t *sp; 1340 1341 requested_transition = 0; 1342 1343 /* 1344 * If the administrator has not set the security level to -1 1345 * to indicate that the kernel should not run multiuser in secure 1346 * mode, and the run script has not set a higher level of security 1347 * than level 1, then put the kernel into secure mode. 1348 */ 1349 if (getsecuritylevel() == 0) 1350 setsecuritylevel(1); 1351 1352 for (sp = sessions; sp; sp = sp->se_next) { 1353 if (sp->se_process) 1354 continue; 1355 if ((pid = start_getty(sp)) == -1) { 1356 /* serious trouble */ 1357 requested_transition = clean_ttys; 1358 break; 1359 } 1360 sp->se_process = pid; 1361 sp->se_started = time((time_t *) 0); 1362 add_session(sp); 1363 } 1364 1365 while (!requested_transition) 1366 if ((pid = waitpid(-1, (int *) 0, 0)) != -1) 1367 collect_child(pid); 1368 1369 return (state_func_t) requested_transition; 1370} 1371 1372/* 1373 * This is an (n*2)+(n^2) algorithm. We hope it isn't run often... 1374 */ 1375static state_func_t 1376clean_ttys(void) 1377{ 1378 session_t *sp, *sprev; 1379 struct ttyent *typ; 1380 int devlen; 1381 char *old_getty, *old_window, *old_type; 1382 1383 /* 1384 * mark all sessions for death, (!SE_PRESENT) 1385 * as we find or create new ones they'll be marked as keepers, 1386 * we'll later nuke all the ones not found in /etc/ttys 1387 */ 1388 for (sp = sessions; sp != NULL; sp = sp->se_next) 1389 sp->se_flags &= ~SE_PRESENT; 1390 1391 devlen = sizeof(_PATH_DEV) - 1; 1392 while ((typ = getttyent()) != NULL) { 1393 for (sprev = 0, sp = sessions; sp; sprev = sp, sp = sp->se_next) 1394 if (strcmp(typ->ty_name, sp->se_device + devlen) == 0) 1395 break; 1396 1397 if (sp) { 1398 /* we want this one to live */ 1399 sp->se_flags |= SE_PRESENT; 1400 if ((typ->ty_status & TTY_ON) == 0 || 1401 typ->ty_getty == 0) { 1402 sp->se_flags |= SE_SHUTDOWN; 1403 kill(sp->se_process, SIGHUP); 1404 continue; 1405 } 1406 sp->se_flags &= ~SE_SHUTDOWN; 1407 old_getty = sp->se_getty ? strdup(sp->se_getty) : 0; 1408 old_window = sp->se_window ? strdup(sp->se_window) : 0; 1409 old_type = sp->se_type ? strdup(sp->se_type) : 0; 1410 if (setupargv(sp, typ) == 0) { 1411 warning("can't parse getty for port %s", 1412 sp->se_device); 1413 sp->se_flags |= SE_SHUTDOWN; 1414 kill(sp->se_process, SIGHUP); 1415 } 1416 else if ( !old_getty 1417 || (!old_type && sp->se_type) 1418 || (old_type && !sp->se_type) 1419 || (!old_window && sp->se_window) 1420 || (old_window && !sp->se_window) 1421 || (strcmp(old_getty, sp->se_getty) != 0) 1422 || (old_window && strcmp(old_window, sp->se_window) != 0) 1423 || (old_type && strcmp(old_type, sp->se_type) != 0) 1424 ) { 1425 /* Don't set SE_SHUTDOWN here */ 1426 sp->se_nspace = 0; 1427 sp->se_started = 0; 1428 kill(sp->se_process, SIGHUP); 1429 } 1430 if (old_getty) 1431 free(old_getty); 1432 if (old_window) 1433 free(old_window); 1434 if (old_type) 1435 free(old_type); 1436 continue; 1437 } 1438 1439 new_session(sprev, typ); 1440 } 1441 1442 endttyent(); 1443 1444 /* 1445 * sweep through and kill all deleted sessions 1446 * ones who's /etc/ttys line was deleted (SE_PRESENT unset) 1447 */ 1448 for (sp = sessions; sp != NULL; sp = sp->se_next) { 1449 if ((sp->se_flags & SE_PRESENT) == 0) { 1450 sp->se_flags |= SE_SHUTDOWN; 1451 kill(sp->se_process, SIGHUP); 1452 } 1453 } 1454 1455 return (state_func_t) multi_user; 1456} 1457 1458/* 1459 * Block further logins. 1460 */ 1461static state_func_t 1462catatonia(void) 1463{ 1464 session_t *sp; 1465 1466 for (sp = sessions; sp; sp = sp->se_next) 1467 sp->se_flags |= SE_SHUTDOWN; 1468 1469 return (state_func_t) multi_user; 1470} 1471 1472/* 1473 * Note SIGALRM. 1474 */ 1475static void 1476alrm_handler(int sig) 1477{ 1478 1479 (void)sig; 1480 clang = 1; 1481} 1482 1483/* 1484 * Bring the system down to single user. 1485 */ 1486static state_func_t 1487death(void) 1488{ 1489 session_t *sp; 1490 int block, blocked; 1491 size_t len; 1492 1493 /* Temporarily block suspend. */ 1494 len = sizeof(blocked); 1495 block = 1; 1496 if (sysctlbyname("kern.suspend_blocked", &blocked, &len, 1497 &block, sizeof(block)) == -1) 1498 blocked = 0; 1499 1500 /* 1501 * Also revoke the TTY here. Because runshutdown() may reopen 1502 * the TTY whose getty we're killing here, there is no guarantee 1503 * runshutdown() will perform the initial open() call, causing 1504 * the terminal attributes to be misconfigured. 1505 */ 1506 for (sp = sessions; sp; sp = sp->se_next) { 1507 sp->se_flags |= SE_SHUTDOWN; 1508 kill(sp->se_process, SIGHUP); 1509 revoke(sp->se_device); 1510 } 1511 1512 /* Try to run the rc.shutdown script within a period of time */ 1513 runshutdown(); 1514 1515 /* Unblock suspend if we blocked it. */ 1516 if (!blocked) 1517 sysctlbyname("kern.suspend_blocked", NULL, NULL, 1518 &blocked, sizeof(blocked)); 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 */ 1527static state_func_t 1528death_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 */ 1565static int 1566runshutdown(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 1688static char * 1689strk(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 1728static void 1729setprocresources(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_SETLOGINCLASS | LOGIN_SETCPUMASK); 1736 login_close(lc); 1737 } 1738} 1739#endif 1740