1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Donn Seeley at Berkeley Software Design, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #ifndef lint 36 static const char copyright[] = 37 "@(#) Copyright (c) 1991, 1993\n\ 38 The Regents of the University of California. All rights reserved.\n"; 39 #endif /* not lint */ 40 41 #ifndef lint 42 #if 0 43 static char sccsid[] = "@(#)init.c 8.1 (Berkeley) 7/15/93"; 44 #endif 45 #endif /* not lint */ 46 47 #include <sys/param.h> 48 #include <sys/boottrace.h> 49 #include <sys/ioctl.h> 50 #include <sys/mman.h> 51 #include <sys/mount.h> 52 #include <sys/reboot.h> 53 #include <sys/stat.h> 54 #include <sys/sysctl.h> 55 #include <sys/uio.h> 56 #include <sys/wait.h> 57 58 #include <db.h> 59 #include <err.h> 60 #include <errno.h> 61 #include <fcntl.h> 62 #include <kenv.h> 63 #include <libutil.h> 64 #include <paths.h> 65 #include <signal.h> 66 #include <stdarg.h> 67 #include <stdbool.h> 68 #include <stdio.h> 69 #include <stdlib.h> 70 #include <string.h> 71 #include <syslog.h> 72 #include <time.h> 73 #include <ttyent.h> 74 #include <unistd.h> 75 76 #ifdef SECURE 77 #include <pwd.h> 78 #endif 79 80 #ifdef LOGIN_CAP 81 #include <login_cap.h> 82 #endif 83 84 #include "mntopts.h" 85 #include "pathnames.h" 86 87 /* 88 * Sleep times; used to prevent thrashing. 89 */ 90 #define GETTY_SPACING 5 /* N secs minimum getty spacing */ 91 #define GETTY_SLEEP 30 /* sleep N secs after spacing problem */ 92 #define GETTY_NSPACE 3 /* max. spacing count to bring reaction */ 93 #define WINDOW_WAIT 3 /* wait N secs after starting window */ 94 #define STALL_TIMEOUT 30 /* wait N secs after warning */ 95 #define DEATH_WATCH 10 /* wait N secs for procs to die */ 96 #define DEATH_SCRIPT 120 /* wait for 2min for /etc/rc.shutdown */ 97 #define RESOURCE_RC "daemon" 98 #define RESOURCE_WINDOW "default" 99 #define RESOURCE_GETTY "default" 100 #define SCRIPT_ARGV_SIZE 3 /* size of argv passed to execute_script, can be increased if needed */ 101 102 static void handle(sig_t, ...); 103 static void delset(sigset_t *, ...); 104 105 static void stall(const char *, ...) __printflike(1, 2); 106 static void warning(const char *, ...) __printflike(1, 2); 107 static void emergency(const char *, ...) __printflike(1, 2); 108 static void disaster(int); 109 static void revoke_ttys(void); 110 static int runshutdown(void); 111 static char *strk(char *); 112 static void runfinal(void); 113 114 /* 115 * We really need a recursive typedef... 116 * The following at least guarantees that the return type of (*state_t)() 117 * is sufficiently wide to hold a function pointer. 118 */ 119 typedef long (*state_func_t)(void); 120 typedef state_func_t (*state_t)(void); 121 122 static state_func_t single_user(void); 123 static state_func_t runcom(void); 124 static state_func_t read_ttys(void); 125 static state_func_t multi_user(void); 126 static state_func_t clean_ttys(void); 127 static state_func_t catatonia(void); 128 static state_func_t death(void); 129 static state_func_t death_single(void); 130 static state_func_t reroot(void); 131 static state_func_t reroot_phase_two(void); 132 133 static state_func_t run_script(const char *); 134 135 static enum { AUTOBOOT, FASTBOOT } runcom_mode = AUTOBOOT; 136 137 static bool Reboot = false; 138 static int howto = RB_AUTOBOOT; 139 140 static bool devfs = false; 141 static char *init_path_argv0; 142 143 static void transition(state_t); 144 static state_t requested_transition; 145 static state_t current_state = death_single; 146 147 static void execute_script(char *argv[]); 148 static void open_console(void); 149 static const char *get_shell(void); 150 static void replace_init(char *path); 151 static void write_stderr(const char *message); 152 153 typedef struct init_session { 154 pid_t se_process; /* controlling process */ 155 time_t se_started; /* used to avoid thrashing */ 156 int se_flags; /* status of session */ 157 #define SE_SHUTDOWN 0x1 /* session won't be restarted */ 158 #define SE_PRESENT 0x2 /* session is in /etc/ttys */ 159 #define SE_IFEXISTS 0x4 /* session defined as "onifexists" */ 160 #define SE_IFCONSOLE 0x8 /* session defined as "onifconsole" */ 161 int se_nspace; /* spacing count */ 162 char *se_device; /* filename of port */ 163 char *se_getty; /* what to run on that port */ 164 char *se_getty_argv_space; /* pre-parsed argument array space */ 165 char **se_getty_argv; /* pre-parsed argument array */ 166 char *se_window; /* window system (started only once) */ 167 char *se_window_argv_space; /* pre-parsed argument array space */ 168 char **se_window_argv; /* pre-parsed argument array */ 169 char *se_type; /* default terminal type */ 170 struct init_session *se_prev; 171 struct init_session *se_next; 172 } session_t; 173 174 static void free_session(session_t *); 175 static session_t *new_session(session_t *, struct ttyent *); 176 static session_t *sessions; 177 178 static char **construct_argv(char *); 179 static void start_window_system(session_t *); 180 static void collect_child(pid_t); 181 static pid_t start_getty(session_t *); 182 static void transition_handler(int); 183 static void alrm_handler(int); 184 static void setsecuritylevel(int); 185 static int getsecuritylevel(void); 186 static int setupargv(session_t *, struct ttyent *); 187 #ifdef LOGIN_CAP 188 static void setprocresources(const char *); 189 #endif 190 static bool clang; 191 192 static int start_session_db(void); 193 static void add_session(session_t *); 194 static void del_session(session_t *); 195 static session_t *find_session(pid_t); 196 static DB *session_db; 197 198 /* 199 * The mother of all processes. 200 */ 201 int 202 main(int argc, char *argv[]) 203 { 204 state_t initial_transition = runcom; 205 char kenv_value[PATH_MAX]; 206 int c, error; 207 struct sigaction sa; 208 sigset_t mask; 209 210 /* Dispose of random users. */ 211 if (getuid() != 0) 212 errx(1, "%s", strerror(EPERM)); 213 214 BOOTTRACE("init(8) starting..."); 215 216 /* System V users like to reexec init. */ 217 if (getpid() != 1) { 218 #ifdef COMPAT_SYSV_INIT 219 /* So give them what they want */ 220 if (argc > 1) { 221 if (strlen(argv[1]) == 1) { 222 char runlevel = *argv[1]; 223 int sig; 224 225 switch (runlevel) { 226 case '0': /* halt + poweroff */ 227 sig = SIGUSR2; 228 break; 229 case '1': /* single-user */ 230 sig = SIGTERM; 231 break; 232 case '6': /* reboot */ 233 sig = SIGINT; 234 break; 235 case 'c': /* block further logins */ 236 sig = SIGTSTP; 237 break; 238 case 'q': /* rescan /etc/ttys */ 239 sig = SIGHUP; 240 break; 241 case 'r': /* remount root */ 242 sig = SIGEMT; 243 break; 244 default: 245 goto invalid; 246 } 247 kill(1, sig); 248 _exit(0); 249 } else 250 invalid: 251 errx(1, "invalid run-level ``%s''", argv[1]); 252 } else 253 #endif 254 errx(1, "already running"); 255 } 256 257 init_path_argv0 = strdup(argv[0]); 258 if (init_path_argv0 == NULL) 259 err(1, "strdup"); 260 261 /* 262 * Note that this does NOT open a file... 263 * Does 'init' deserve its own facility number? 264 */ 265 openlog("init", LOG_CONS, LOG_AUTH); 266 267 /* 268 * Create an initial session. 269 */ 270 if (setsid() < 0 && (errno != EPERM || getsid(0) != 1)) 271 warning("initial setsid() failed: %m"); 272 273 /* 274 * Establish an initial user so that programs running 275 * single user do not freak out and die (like passwd). 276 */ 277 if (setlogin("root") < 0) 278 warning("setlogin() failed: %m"); 279 280 /* 281 * This code assumes that we always get arguments through flags, 282 * never through bits set in some random machine register. 283 */ 284 while ((c = getopt(argc, argv, "dsfr")) != -1) 285 switch (c) { 286 case 'd': 287 devfs = true; 288 break; 289 case 's': 290 initial_transition = single_user; 291 break; 292 case 'f': 293 runcom_mode = FASTBOOT; 294 break; 295 case 'r': 296 initial_transition = reroot_phase_two; 297 break; 298 default: 299 warning("unrecognized flag '-%c'", c); 300 break; 301 } 302 303 if (optind != argc) 304 warning("ignoring excess arguments"); 305 306 /* 307 * We catch or block signals rather than ignore them, 308 * so that they get reset on exec. 309 */ 310 handle(disaster, SIGABRT, SIGFPE, SIGILL, SIGSEGV, SIGBUS, SIGSYS, 311 SIGXCPU, SIGXFSZ, 0); 312 handle(transition_handler, SIGHUP, SIGINT, SIGEMT, SIGTERM, SIGTSTP, 313 SIGUSR1, SIGUSR2, SIGWINCH, 0); 314 handle(alrm_handler, SIGALRM, 0); 315 sigfillset(&mask); 316 delset(&mask, SIGABRT, SIGFPE, SIGILL, SIGSEGV, SIGBUS, SIGSYS, 317 SIGXCPU, SIGXFSZ, SIGHUP, SIGINT, SIGEMT, SIGTERM, SIGTSTP, 318 SIGALRM, SIGUSR1, SIGUSR2, SIGWINCH, 0); 319 sigprocmask(SIG_SETMASK, &mask, NULL); 320 sigemptyset(&sa.sa_mask); 321 sa.sa_flags = 0; 322 sa.sa_handler = SIG_IGN; 323 sigaction(SIGTTIN, &sa, NULL); 324 sigaction(SIGTTOU, &sa, NULL); 325 326 /* 327 * Paranoia. 328 */ 329 close(0); 330 close(1); 331 close(2); 332 333 if (kenv(KENV_GET, "init_exec", kenv_value, sizeof(kenv_value)) > 0) { 334 replace_init(kenv_value); 335 _exit(0); /* reboot */ 336 } 337 338 if (kenv(KENV_GET, "init_script", kenv_value, sizeof(kenv_value)) > 0) { 339 state_func_t next_transition; 340 341 if ((next_transition = run_script(kenv_value)) != NULL) 342 initial_transition = (state_t) next_transition; 343 } 344 345 if (kenv(KENV_GET, "init_chroot", kenv_value, sizeof(kenv_value)) > 0) { 346 if (chdir(kenv_value) != 0 || chroot(".") != 0) 347 warning("Can't chroot to %s: %m", kenv_value); 348 } 349 350 /* 351 * Additional check if devfs needs to be mounted: 352 * If "/" and "/dev" have the same device number, 353 * then it hasn't been mounted yet. 354 */ 355 if (!devfs) { 356 struct stat stst; 357 dev_t root_devno; 358 359 stat("/", &stst); 360 root_devno = stst.st_dev; 361 if (stat("/dev", &stst) != 0) 362 warning("Can't stat /dev: %m"); 363 else if (stst.st_dev == root_devno) 364 devfs = true; 365 } 366 367 if (devfs) { 368 struct iovec iov[4]; 369 char *s; 370 int i; 371 372 char _fstype[] = "fstype"; 373 char _devfs[] = "devfs"; 374 char _fspath[] = "fspath"; 375 char _path_dev[]= _PATH_DEV; 376 377 iov[0].iov_base = _fstype; 378 iov[0].iov_len = sizeof(_fstype); 379 iov[1].iov_base = _devfs; 380 iov[1].iov_len = sizeof(_devfs); 381 iov[2].iov_base = _fspath; 382 iov[2].iov_len = sizeof(_fspath); 383 /* 384 * Try to avoid the trailing slash in _PATH_DEV. 385 * Be *very* defensive. 386 */ 387 s = strdup(_PATH_DEV); 388 if (s != NULL) { 389 i = strlen(s); 390 if (i > 0 && s[i - 1] == '/') 391 s[i - 1] = '\0'; 392 iov[3].iov_base = s; 393 iov[3].iov_len = strlen(s) + 1; 394 } else { 395 iov[3].iov_base = _path_dev; 396 iov[3].iov_len = sizeof(_path_dev); 397 } 398 nmount(iov, 4, 0); 399 if (s != NULL) 400 free(s); 401 } 402 403 if (initial_transition != reroot_phase_two) { 404 /* 405 * Unmount reroot leftovers. This runs after init(8) 406 * gets reexecuted after reroot_phase_two() is done. 407 */ 408 error = unmount(_PATH_REROOT, MNT_FORCE); 409 if (error != 0 && errno != EINVAL) 410 warning("Cannot unmount %s: %m", _PATH_REROOT); 411 } 412 413 /* 414 * Start the state machine. 415 */ 416 transition(initial_transition); 417 418 /* 419 * Should never reach here. 420 */ 421 return 1; 422 } 423 424 /* 425 * Associate a function with a signal handler. 426 */ 427 static void 428 handle(sig_t handler, ...) 429 { 430 int sig; 431 struct sigaction sa; 432 sigset_t mask_everything; 433 va_list ap; 434 va_start(ap, handler); 435 436 sa.sa_handler = handler; 437 sigfillset(&mask_everything); 438 439 while ((sig = va_arg(ap, int)) != 0) { 440 sa.sa_mask = mask_everything; 441 /* XXX SA_RESTART? */ 442 sa.sa_flags = sig == SIGCHLD ? SA_NOCLDSTOP : 0; 443 sigaction(sig, &sa, NULL); 444 } 445 va_end(ap); 446 } 447 448 /* 449 * Delete a set of signals from a mask. 450 */ 451 static void 452 delset(sigset_t *maskp, ...) 453 { 454 int sig; 455 va_list ap; 456 va_start(ap, maskp); 457 458 while ((sig = va_arg(ap, int)) != 0) 459 sigdelset(maskp, sig); 460 va_end(ap); 461 } 462 463 /* 464 * Log a message and sleep for a while (to give someone an opportunity 465 * to read it and to save log or hardcopy output if the problem is chronic). 466 * NB: should send a message to the session logger to avoid blocking. 467 */ 468 static void 469 stall(const char *message, ...) 470 { 471 va_list ap; 472 va_start(ap, message); 473 474 vsyslog(LOG_ALERT, message, ap); 475 va_end(ap); 476 sleep(STALL_TIMEOUT); 477 } 478 479 /* 480 * Like stall(), but doesn't sleep. 481 * If cpp had variadic macros, the two functions could be #defines for another. 482 * NB: should send a message to the session logger to avoid blocking. 483 */ 484 static void 485 warning(const char *message, ...) 486 { 487 va_list ap; 488 va_start(ap, message); 489 490 vsyslog(LOG_ALERT, message, ap); 491 va_end(ap); 492 } 493 494 /* 495 * Log an emergency message. 496 * NB: should send a message to the session logger to avoid blocking. 497 */ 498 static void 499 emergency(const char *message, ...) 500 { 501 va_list ap; 502 va_start(ap, message); 503 504 vsyslog(LOG_EMERG, message, ap); 505 va_end(ap); 506 } 507 508 /* 509 * Catch an unexpected signal. 510 */ 511 static void 512 disaster(int sig) 513 { 514 515 emergency("fatal signal: %s", 516 (unsigned)sig < NSIG ? sys_siglist[sig] : "unknown signal"); 517 518 sleep(STALL_TIMEOUT); 519 _exit(sig); /* reboot */ 520 } 521 522 /* 523 * Get the security level of the kernel. 524 */ 525 static int 526 getsecuritylevel(void) 527 { 528 #ifdef KERN_SECURELVL 529 int name[2], curlevel; 530 size_t len; 531 532 name[0] = CTL_KERN; 533 name[1] = KERN_SECURELVL; 534 len = sizeof curlevel; 535 if (sysctl(name, 2, &curlevel, &len, NULL, 0) == -1) { 536 emergency("cannot get kernel security level: %m"); 537 return (-1); 538 } 539 return (curlevel); 540 #else 541 return (-1); 542 #endif 543 } 544 545 /* 546 * Set the security level of the kernel. 547 */ 548 static void 549 setsecuritylevel(int newlevel) 550 { 551 #ifdef KERN_SECURELVL 552 int name[2], curlevel; 553 554 curlevel = getsecuritylevel(); 555 if (newlevel == curlevel) 556 return; 557 name[0] = CTL_KERN; 558 name[1] = KERN_SECURELVL; 559 if (sysctl(name, 2, NULL, NULL, &newlevel, sizeof newlevel) == -1) { 560 emergency( 561 "cannot change kernel security level from %d to %d: %m", 562 curlevel, newlevel); 563 return; 564 } 565 #ifdef SECURE 566 warning("kernel security level changed from %d to %d", 567 curlevel, newlevel); 568 #endif 569 #endif 570 } 571 572 /* 573 * Change states in the finite state machine. 574 * The initial state is passed as an argument. 575 */ 576 static void 577 transition(state_t s) 578 { 579 580 current_state = s; 581 for (;;) 582 current_state = (state_t) (*current_state)(); 583 } 584 585 /* 586 * Start a session and allocate a controlling terminal. 587 * Only called by children of init after forking. 588 */ 589 static void 590 open_console(void) 591 { 592 int fd; 593 594 /* 595 * Try to open /dev/console. Open the device with O_NONBLOCK to 596 * prevent potential blocking on a carrier. 597 */ 598 revoke(_PATH_CONSOLE); 599 if ((fd = open(_PATH_CONSOLE, O_RDWR | O_NONBLOCK)) != -1) { 600 (void)fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) & ~O_NONBLOCK); 601 if (login_tty(fd) == 0) 602 return; 603 close(fd); 604 } 605 606 /* No luck. Log output to file if possible. */ 607 if ((fd = open(_PATH_DEVNULL, O_RDWR)) == -1) { 608 stall("cannot open null device."); 609 _exit(1); 610 } 611 if (fd != STDIN_FILENO) { 612 dup2(fd, STDIN_FILENO); 613 close(fd); 614 } 615 fd = open(_PATH_INITLOG, O_WRONLY | O_APPEND | O_CREAT, 0644); 616 if (fd == -1) 617 dup2(STDIN_FILENO, STDOUT_FILENO); 618 else if (fd != STDOUT_FILENO) { 619 dup2(fd, STDOUT_FILENO); 620 close(fd); 621 } 622 dup2(STDOUT_FILENO, STDERR_FILENO); 623 } 624 625 static const char * 626 get_shell(void) 627 { 628 static char kenv_value[PATH_MAX]; 629 630 if (kenv(KENV_GET, "init_shell", kenv_value, sizeof(kenv_value)) > 0) 631 return kenv_value; 632 else 633 return _PATH_BSHELL; 634 } 635 636 static void 637 write_stderr(const char *message) 638 { 639 640 write(STDERR_FILENO, message, strlen(message)); 641 } 642 643 static int 644 read_file(const char *path, void **bufp, size_t *bufsizep) 645 { 646 struct stat sb; 647 size_t bufsize; 648 void *buf; 649 ssize_t nbytes; 650 int error, fd; 651 652 fd = open(path, O_RDONLY); 653 if (fd < 0) { 654 emergency("%s: %m", path); 655 return (-1); 656 } 657 658 error = fstat(fd, &sb); 659 if (error != 0) { 660 emergency("fstat: %m"); 661 close(fd); 662 return (error); 663 } 664 665 bufsize = sb.st_size; 666 buf = malloc(bufsize); 667 if (buf == NULL) { 668 emergency("malloc: %m"); 669 close(fd); 670 return (error); 671 } 672 673 nbytes = read(fd, buf, bufsize); 674 if (nbytes != (ssize_t)bufsize) { 675 emergency("read: %m"); 676 close(fd); 677 free(buf); 678 return (error); 679 } 680 681 error = close(fd); 682 if (error != 0) { 683 emergency("close: %m"); 684 free(buf); 685 return (error); 686 } 687 688 *bufp = buf; 689 *bufsizep = bufsize; 690 691 return (0); 692 } 693 694 static int 695 create_file(const char *path, const void *buf, size_t bufsize) 696 { 697 ssize_t nbytes; 698 int error, fd; 699 700 fd = open(path, O_WRONLY | O_CREAT | O_EXCL, 0700); 701 if (fd < 0) { 702 emergency("%s: %m", path); 703 return (-1); 704 } 705 706 nbytes = write(fd, buf, bufsize); 707 if (nbytes != (ssize_t)bufsize) { 708 emergency("write: %m"); 709 close(fd); 710 return (-1); 711 } 712 713 error = close(fd); 714 if (error != 0) { 715 emergency("close: %m"); 716 return (-1); 717 } 718 719 return (0); 720 } 721 722 static int 723 mount_tmpfs(const char *fspath) 724 { 725 struct iovec *iov; 726 char errmsg[255]; 727 int error, iovlen; 728 729 iov = NULL; 730 iovlen = 0; 731 memset(errmsg, 0, sizeof(errmsg)); 732 build_iovec(&iov, &iovlen, "fstype", 733 __DECONST(void *, "tmpfs"), (size_t)-1); 734 build_iovec(&iov, &iovlen, "fspath", 735 __DECONST(void *, fspath), (size_t)-1); 736 build_iovec(&iov, &iovlen, "errmsg", 737 errmsg, sizeof(errmsg)); 738 739 error = nmount(iov, iovlen, 0); 740 if (error != 0) { 741 if (*errmsg != '\0') { 742 emergency("cannot mount tmpfs on %s: %s: %m", 743 fspath, errmsg); 744 } else { 745 emergency("cannot mount tmpfs on %s: %m", 746 fspath); 747 } 748 return (error); 749 } 750 return (0); 751 } 752 753 static state_func_t 754 reroot(void) 755 { 756 void *buf; 757 size_t bufsize; 758 int error; 759 760 buf = NULL; 761 bufsize = 0; 762 763 revoke_ttys(); 764 runshutdown(); 765 766 /* 767 * Make sure nobody can interfere with our scheme. 768 * Ignore ESRCH, which can apparently happen when 769 * there are no processes to kill. 770 */ 771 error = kill(-1, SIGKILL); 772 if (error != 0 && errno != ESRCH) { 773 emergency("kill(2) failed: %m"); 774 goto out; 775 } 776 777 /* 778 * Copy the init binary into tmpfs, so that we can unmount 779 * the old rootfs without committing suicide. 780 */ 781 error = read_file(init_path_argv0, &buf, &bufsize); 782 if (error != 0) 783 goto out; 784 error = mount_tmpfs(_PATH_REROOT); 785 if (error != 0) 786 goto out; 787 error = create_file(_PATH_REROOT_INIT, buf, bufsize); 788 if (error != 0) 789 goto out; 790 791 /* 792 * Execute the temporary init. 793 */ 794 execl(_PATH_REROOT_INIT, _PATH_REROOT_INIT, "-r", NULL); 795 emergency("cannot exec %s: %m", _PATH_REROOT_INIT); 796 797 out: 798 emergency("reroot failed; going to single user mode"); 799 free(buf); 800 return (state_func_t) single_user; 801 } 802 803 static state_func_t 804 reroot_phase_two(void) 805 { 806 char init_path[PATH_MAX], *path, *path_component; 807 size_t init_path_len; 808 int nbytes, error; 809 810 /* 811 * Ask the kernel to mount the new rootfs. 812 */ 813 error = reboot(RB_REROOT); 814 if (error != 0) { 815 emergency("RB_REBOOT failed: %m"); 816 goto out; 817 } 818 819 /* 820 * Figure out where the destination init(8) binary is. Note that 821 * the path could be different than what we've started with. Use 822 * the value from kenv, if set, or the one from sysctl otherwise. 823 * The latter defaults to a hardcoded value, but can be overridden 824 * by a build time option. 825 */ 826 nbytes = kenv(KENV_GET, "init_path", init_path, sizeof(init_path)); 827 if (nbytes <= 0) { 828 init_path_len = sizeof(init_path); 829 error = sysctlbyname("kern.init_path", 830 init_path, &init_path_len, NULL, 0); 831 if (error != 0) { 832 emergency("failed to retrieve kern.init_path: %m"); 833 goto out; 834 } 835 } 836 837 /* 838 * Repeat the init search logic from sys/kern/init_path.c 839 */ 840 path_component = init_path; 841 while ((path = strsep(&path_component, ":")) != NULL) { 842 /* 843 * Execute init(8) from the new rootfs. 844 */ 845 execl(path, path, NULL); 846 } 847 emergency("cannot exec init from %s: %m", init_path); 848 849 out: 850 emergency("reroot failed; going to single user mode"); 851 return (state_func_t) single_user; 852 } 853 854 /* 855 * Bring the system up single user. 856 */ 857 static state_func_t 858 single_user(void) 859 { 860 pid_t pid, wpid; 861 int status; 862 sigset_t mask; 863 const char *shell; 864 char *argv[2]; 865 struct timeval tv, tn; 866 #ifdef SECURE 867 struct ttyent *typ; 868 struct passwd *pp; 869 static const char banner[] = 870 "Enter root password, or ^D to go multi-user\n"; 871 char *clear, *password; 872 #endif 873 #ifdef DEBUGSHELL 874 char altshell[128]; 875 #endif 876 877 if (Reboot) { 878 /* Instead of going single user, let's reboot the machine */ 879 BOOTTRACE("shutting down the system"); 880 sync(); 881 /* Run scripts after all processes have been terminated. */ 882 runfinal(); 883 if (reboot(howto) == -1) { 884 emergency("reboot(%#x) failed, %m", howto); 885 _exit(1); /* panic and reboot */ 886 } 887 warning("reboot(%#x) returned", howto); 888 _exit(0); /* panic as well */ 889 } 890 891 BOOTTRACE("going to single user mode"); 892 shell = get_shell(); 893 894 if ((pid = fork()) == 0) { 895 /* 896 * Start the single user session. 897 */ 898 open_console(); 899 900 #ifdef SECURE 901 /* 902 * Check the root password. 903 * We don't care if the console is 'on' by default; 904 * it's the only tty that can be 'off' and 'secure'. 905 */ 906 typ = getttynam("console"); 907 pp = getpwnam("root"); 908 if (typ && (typ->ty_status & TTY_SECURE) == 0 && 909 pp && *pp->pw_passwd) { 910 write_stderr(banner); 911 for (;;) { 912 clear = getpass("Password:"); 913 if (clear == NULL || *clear == '\0') 914 _exit(0); 915 password = crypt(clear, pp->pw_passwd); 916 explicit_bzero(clear, _PASSWORD_LEN); 917 if (password != NULL && 918 strcmp(password, pp->pw_passwd) == 0) 919 break; 920 warning("single-user login failed\n"); 921 } 922 } 923 endttyent(); 924 endpwent(); 925 #endif /* SECURE */ 926 927 #ifdef DEBUGSHELL 928 { 929 char *cp = altshell; 930 int num; 931 932 #define SHREQUEST "Enter full pathname of shell or RETURN for " 933 write_stderr(SHREQUEST); 934 write_stderr(shell); 935 write_stderr(": "); 936 while ((num = read(STDIN_FILENO, cp, 1)) != -1 && 937 num != 0 && *cp != '\n' && cp < &altshell[127]) 938 cp++; 939 *cp = '\0'; 940 if (altshell[0] != '\0') 941 shell = altshell; 942 } 943 #endif /* DEBUGSHELL */ 944 945 /* 946 * Unblock signals. 947 * We catch all the interesting ones, 948 * and those are reset to SIG_DFL on exec. 949 */ 950 sigemptyset(&mask); 951 sigprocmask(SIG_SETMASK, &mask, NULL); 952 953 /* 954 * Fire off a shell. 955 * If the default one doesn't work, try the Bourne shell. 956 */ 957 958 char name[] = "-sh"; 959 960 argv[0] = name; 961 argv[1] = NULL; 962 execv(shell, argv); 963 emergency("can't exec %s for single user: %m", shell); 964 execv(_PATH_BSHELL, argv); 965 emergency("can't exec %s for single user: %m", _PATH_BSHELL); 966 sleep(STALL_TIMEOUT); 967 _exit(1); 968 } 969 970 if (pid == -1) { 971 /* 972 * We are seriously hosed. Do our best. 973 */ 974 emergency("can't fork single-user shell, trying again"); 975 while (waitpid(-1, (int *) 0, WNOHANG) > 0) 976 continue; 977 return (state_func_t) single_user; 978 } 979 980 requested_transition = 0; 981 do { 982 if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1) 983 collect_child(wpid); 984 if (wpid == -1) { 985 if (errno == EINTR) 986 continue; 987 warning("wait for single-user shell failed: %m; restarting"); 988 return (state_func_t) single_user; 989 } 990 if (wpid == pid && WIFSTOPPED(status)) { 991 warning("init: shell stopped, restarting\n"); 992 kill(pid, SIGCONT); 993 wpid = -1; 994 } 995 } while (wpid != pid && !requested_transition); 996 997 if (requested_transition) 998 return (state_func_t) requested_transition; 999 1000 if (!WIFEXITED(status)) { 1001 if (WTERMSIG(status) == SIGKILL) { 1002 /* 1003 * reboot(8) killed shell? 1004 */ 1005 warning("single user shell terminated."); 1006 gettimeofday(&tv, NULL); 1007 tn = tv; 1008 tv.tv_sec += STALL_TIMEOUT; 1009 while (tv.tv_sec > tn.tv_sec || (tv.tv_sec == 1010 tn.tv_sec && tv.tv_usec > tn.tv_usec)) { 1011 sleep(1); 1012 gettimeofday(&tn, NULL); 1013 } 1014 _exit(0); 1015 } else { 1016 warning("single user shell terminated, restarting"); 1017 return (state_func_t) single_user; 1018 } 1019 } 1020 1021 runcom_mode = FASTBOOT; 1022 return (state_func_t) runcom; 1023 } 1024 1025 /* 1026 * Run the system startup script. 1027 */ 1028 static state_func_t 1029 runcom(void) 1030 { 1031 state_func_t next_transition; 1032 1033 BOOTTRACE("/etc/rc starting..."); 1034 if ((next_transition = run_script(_PATH_RUNCOM)) != NULL) 1035 return next_transition; 1036 BOOTTRACE("/etc/rc finished"); 1037 1038 runcom_mode = AUTOBOOT; /* the default */ 1039 return (state_func_t) read_ttys; 1040 } 1041 1042 static void 1043 execute_script(char *argv[]) 1044 { 1045 struct sigaction sa; 1046 char* sh_argv[3 + SCRIPT_ARGV_SIZE]; 1047 const char *shell, *script; 1048 int error, sh_argv_len, i; 1049 1050 bzero(&sa, sizeof(sa)); 1051 sigemptyset(&sa.sa_mask); 1052 sa.sa_handler = SIG_IGN; 1053 sigaction(SIGTSTP, &sa, NULL); 1054 sigaction(SIGHUP, &sa, NULL); 1055 1056 open_console(); 1057 1058 sigprocmask(SIG_SETMASK, &sa.sa_mask, NULL); 1059 #ifdef LOGIN_CAP 1060 setprocresources(RESOURCE_RC); 1061 #endif 1062 1063 /* 1064 * Try to directly execute the script first. If it 1065 * fails, try the old method of passing the script path 1066 * to sh(1). Don't complain if it fails because of 1067 * the missing execute bit. 1068 */ 1069 script = argv[0]; 1070 error = access(script, X_OK); 1071 if (error == 0) { 1072 execv(script, argv); 1073 warning("can't directly exec %s: %m", script); 1074 } else if (errno != EACCES) { 1075 warning("can't access %s: %m", script); 1076 } 1077 1078 shell = get_shell(); 1079 sh_argv[0] = __DECONST(char*, shell); 1080 sh_argv_len = 1; 1081 #ifdef SECURE 1082 if (strcmp(shell, _PATH_BSHELL) == 0) { 1083 sh_argv[1] = __DECONST(char*, "-o"); 1084 sh_argv[2] = __DECONST(char*, "verify"); 1085 sh_argv_len = 3; 1086 } 1087 #endif 1088 for (i = 0; i != SCRIPT_ARGV_SIZE; ++i) 1089 sh_argv[i + sh_argv_len] = argv[i]; 1090 execv(shell, sh_argv); 1091 stall("can't exec %s for %s: %m", shell, script); 1092 } 1093 1094 /* 1095 * Execute binary, replacing init(8) as PID 1. 1096 */ 1097 static void 1098 replace_init(char *path) 1099 { 1100 char *argv[SCRIPT_ARGV_SIZE]; 1101 1102 argv[0] = path; 1103 argv[1] = NULL; 1104 1105 execute_script(argv); 1106 } 1107 1108 /* 1109 * Run a shell script. 1110 * Returns 0 on success, otherwise the next transition to enter: 1111 * - single_user if fork/execv/waitpid failed, or if the script 1112 * terminated with a signal or exit code != 0. 1113 * - death_single if a SIGTERM was delivered to init(8). 1114 */ 1115 static state_func_t 1116 run_script(const char *script) 1117 { 1118 pid_t pid, wpid; 1119 int status; 1120 char *argv[SCRIPT_ARGV_SIZE]; 1121 const char *shell; 1122 1123 shell = get_shell(); 1124 1125 if ((pid = fork()) == 0) { 1126 1127 char _autoboot[] = "autoboot"; 1128 1129 argv[0] = __DECONST(char *, script); 1130 argv[1] = runcom_mode == AUTOBOOT ? _autoboot : NULL; 1131 argv[2] = NULL; 1132 1133 execute_script(argv); 1134 sleep(STALL_TIMEOUT); 1135 _exit(1); /* force single user mode */ 1136 } 1137 1138 if (pid == -1) { 1139 emergency("can't fork for %s on %s: %m", shell, script); 1140 while (waitpid(-1, (int *) 0, WNOHANG) > 0) 1141 continue; 1142 sleep(STALL_TIMEOUT); 1143 return (state_func_t) single_user; 1144 } 1145 1146 /* 1147 * Copied from single_user(). This is a bit paranoid. 1148 */ 1149 requested_transition = 0; 1150 do { 1151 if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1) 1152 collect_child(wpid); 1153 if (requested_transition == death_single || 1154 requested_transition == reroot) 1155 return (state_func_t) requested_transition; 1156 if (wpid == -1) { 1157 if (errno == EINTR) 1158 continue; 1159 warning("wait for %s on %s failed: %m; going to " 1160 "single user mode", shell, script); 1161 return (state_func_t) single_user; 1162 } 1163 if (wpid == pid && WIFSTOPPED(status)) { 1164 warning("init: %s on %s stopped, restarting\n", 1165 shell, script); 1166 kill(pid, SIGCONT); 1167 wpid = -1; 1168 } 1169 } while (wpid != pid); 1170 1171 if (WIFSIGNALED(status) && WTERMSIG(status) == SIGTERM && 1172 requested_transition == catatonia) { 1173 /* /etc/rc executed /sbin/reboot; wait for the end quietly */ 1174 sigset_t s; 1175 1176 sigfillset(&s); 1177 for (;;) 1178 sigsuspend(&s); 1179 } 1180 1181 if (!WIFEXITED(status)) { 1182 warning("%s on %s terminated abnormally, going to single " 1183 "user mode", shell, script); 1184 return (state_func_t) single_user; 1185 } 1186 1187 if (WEXITSTATUS(status)) 1188 return (state_func_t) single_user; 1189 1190 return (state_func_t) 0; 1191 } 1192 1193 /* 1194 * Open the session database. 1195 * 1196 * NB: We could pass in the size here; is it necessary? 1197 */ 1198 static int 1199 start_session_db(void) 1200 { 1201 if (session_db && (*session_db->close)(session_db)) 1202 emergency("session database close: %m"); 1203 if ((session_db = dbopen(NULL, O_RDWR, 0, DB_HASH, NULL)) == NULL) { 1204 emergency("session database open: %m"); 1205 return (1); 1206 } 1207 return (0); 1208 1209 } 1210 1211 /* 1212 * Add a new login session. 1213 */ 1214 static void 1215 add_session(session_t *sp) 1216 { 1217 DBT key; 1218 DBT data; 1219 1220 key.data = &sp->se_process; 1221 key.size = sizeof sp->se_process; 1222 data.data = &sp; 1223 data.size = sizeof sp; 1224 1225 if ((*session_db->put)(session_db, &key, &data, 0)) 1226 emergency("insert %d: %m", sp->se_process); 1227 } 1228 1229 /* 1230 * Delete an old login session. 1231 */ 1232 static void 1233 del_session(session_t *sp) 1234 { 1235 DBT key; 1236 1237 key.data = &sp->se_process; 1238 key.size = sizeof sp->se_process; 1239 1240 if ((*session_db->del)(session_db, &key, 0)) 1241 emergency("delete %d: %m", sp->se_process); 1242 } 1243 1244 /* 1245 * Look up a login session by pid. 1246 */ 1247 static session_t * 1248 find_session(pid_t pid) 1249 { 1250 DBT key; 1251 DBT data; 1252 session_t *ret; 1253 1254 key.data = &pid; 1255 key.size = sizeof pid; 1256 if ((*session_db->get)(session_db, &key, &data, 0) != 0) 1257 return 0; 1258 bcopy(data.data, (char *)&ret, sizeof(ret)); 1259 return ret; 1260 } 1261 1262 /* 1263 * Construct an argument vector from a command line. 1264 */ 1265 static char ** 1266 construct_argv(char *command) 1267 { 1268 int argc = 0; 1269 char **argv = (char **) malloc(((strlen(command) + 1) / 2 + 1) 1270 * sizeof (char *)); 1271 1272 if ((argv[argc++] = strk(command)) == NULL) { 1273 free(argv); 1274 return (NULL); 1275 } 1276 while ((argv[argc++] = strk((char *) 0)) != NULL) 1277 continue; 1278 return argv; 1279 } 1280 1281 /* 1282 * Deallocate a session descriptor. 1283 */ 1284 static void 1285 free_session(session_t *sp) 1286 { 1287 free(sp->se_device); 1288 if (sp->se_getty) { 1289 free(sp->se_getty); 1290 free(sp->se_getty_argv_space); 1291 free(sp->se_getty_argv); 1292 } 1293 if (sp->se_window) { 1294 free(sp->se_window); 1295 free(sp->se_window_argv_space); 1296 free(sp->se_window_argv); 1297 } 1298 if (sp->se_type) 1299 free(sp->se_type); 1300 free(sp); 1301 } 1302 1303 /* 1304 * Allocate a new session descriptor. 1305 * Mark it SE_PRESENT. 1306 */ 1307 static session_t * 1308 new_session(session_t *sprev, struct ttyent *typ) 1309 { 1310 session_t *sp; 1311 1312 if ((typ->ty_status & TTY_ON) == 0 || 1313 typ->ty_name == 0 || 1314 typ->ty_getty == 0) 1315 return 0; 1316 1317 sp = (session_t *) calloc(1, sizeof (session_t)); 1318 1319 sp->se_flags |= SE_PRESENT; 1320 1321 if ((typ->ty_status & TTY_IFEXISTS) != 0) 1322 sp->se_flags |= SE_IFEXISTS; 1323 1324 if ((typ->ty_status & TTY_IFCONSOLE) != 0) 1325 sp->se_flags |= SE_IFCONSOLE; 1326 1327 if (asprintf(&sp->se_device, "%s%s", _PATH_DEV, typ->ty_name) < 0) 1328 err(1, "asprintf"); 1329 1330 if (setupargv(sp, typ) == 0) { 1331 free_session(sp); 1332 return (0); 1333 } 1334 1335 sp->se_next = 0; 1336 if (sprev == NULL) { 1337 sessions = sp; 1338 sp->se_prev = 0; 1339 } else { 1340 sprev->se_next = sp; 1341 sp->se_prev = sprev; 1342 } 1343 1344 return sp; 1345 } 1346 1347 /* 1348 * Calculate getty and if useful window argv vectors. 1349 */ 1350 static int 1351 setupargv(session_t *sp, struct ttyent *typ) 1352 { 1353 1354 if (sp->se_getty) { 1355 free(sp->se_getty); 1356 free(sp->se_getty_argv_space); 1357 free(sp->se_getty_argv); 1358 } 1359 if (asprintf(&sp->se_getty, "%s %s", typ->ty_getty, typ->ty_name) < 0) 1360 err(1, "asprintf"); 1361 sp->se_getty_argv_space = strdup(sp->se_getty); 1362 sp->se_getty_argv = construct_argv(sp->se_getty_argv_space); 1363 if (sp->se_getty_argv == NULL) { 1364 warning("can't parse getty for port %s", sp->se_device); 1365 free(sp->se_getty); 1366 free(sp->se_getty_argv_space); 1367 sp->se_getty = sp->se_getty_argv_space = 0; 1368 return (0); 1369 } 1370 if (sp->se_window) { 1371 free(sp->se_window); 1372 free(sp->se_window_argv_space); 1373 free(sp->se_window_argv); 1374 } 1375 sp->se_window = sp->se_window_argv_space = 0; 1376 sp->se_window_argv = 0; 1377 if (typ->ty_window) { 1378 sp->se_window = strdup(typ->ty_window); 1379 sp->se_window_argv_space = strdup(sp->se_window); 1380 sp->se_window_argv = construct_argv(sp->se_window_argv_space); 1381 if (sp->se_window_argv == NULL) { 1382 warning("can't parse window for port %s", 1383 sp->se_device); 1384 free(sp->se_window_argv_space); 1385 free(sp->se_window); 1386 sp->se_window = sp->se_window_argv_space = 0; 1387 return (0); 1388 } 1389 } 1390 if (sp->se_type) 1391 free(sp->se_type); 1392 sp->se_type = typ->ty_type ? strdup(typ->ty_type) : 0; 1393 return (1); 1394 } 1395 1396 /* 1397 * Walk the list of ttys and create sessions for each active line. 1398 */ 1399 static state_func_t 1400 read_ttys(void) 1401 { 1402 session_t *sp, *snext; 1403 struct ttyent *typ; 1404 1405 /* 1406 * Destroy any previous session state. 1407 * There shouldn't be any, but just in case... 1408 */ 1409 for (sp = sessions; sp; sp = snext) { 1410 snext = sp->se_next; 1411 free_session(sp); 1412 } 1413 sessions = 0; 1414 if (start_session_db()) 1415 return (state_func_t) single_user; 1416 1417 /* 1418 * Allocate a session entry for each active port. 1419 * Note that sp starts at 0. 1420 */ 1421 while ((typ = getttyent()) != NULL) 1422 if ((snext = new_session(sp, typ)) != NULL) 1423 sp = snext; 1424 1425 endttyent(); 1426 1427 return (state_func_t) multi_user; 1428 } 1429 1430 /* 1431 * Start a window system running. 1432 */ 1433 static void 1434 start_window_system(session_t *sp) 1435 { 1436 pid_t pid; 1437 sigset_t mask; 1438 char term[64], *env[2]; 1439 int status; 1440 1441 if ((pid = fork()) == -1) { 1442 emergency("can't fork for window system on port %s: %m", 1443 sp->se_device); 1444 /* hope that getty fails and we can try again */ 1445 return; 1446 } 1447 if (pid) { 1448 waitpid(-1, &status, 0); 1449 return; 1450 } 1451 1452 /* reparent window process to the init to not make a zombie on exit */ 1453 if ((pid = fork()) == -1) { 1454 emergency("can't fork for window system on port %s: %m", 1455 sp->se_device); 1456 _exit(1); 1457 } 1458 if (pid) 1459 _exit(0); 1460 1461 sigemptyset(&mask); 1462 sigprocmask(SIG_SETMASK, &mask, NULL); 1463 1464 if (setsid() < 0) 1465 emergency("setsid failed (window) %m"); 1466 1467 #ifdef LOGIN_CAP 1468 setprocresources(RESOURCE_WINDOW); 1469 #endif 1470 if (sp->se_type) { 1471 /* Don't use malloc after fork */ 1472 strcpy(term, "TERM="); 1473 strlcat(term, sp->se_type, sizeof(term)); 1474 env[0] = term; 1475 env[1] = NULL; 1476 } 1477 else 1478 env[0] = NULL; 1479 execve(sp->se_window_argv[0], sp->se_window_argv, env); 1480 stall("can't exec window system '%s' for port %s: %m", 1481 sp->se_window_argv[0], sp->se_device); 1482 _exit(1); 1483 } 1484 1485 /* 1486 * Start a login session running. 1487 */ 1488 static pid_t 1489 start_getty(session_t *sp) 1490 { 1491 pid_t pid; 1492 sigset_t mask; 1493 time_t current_time = time((time_t *) 0); 1494 int too_quick = 0; 1495 char term[64], *env[2]; 1496 1497 if (current_time >= sp->se_started && 1498 current_time - sp->se_started < GETTY_SPACING) { 1499 if (++sp->se_nspace > GETTY_NSPACE) { 1500 sp->se_nspace = 0; 1501 too_quick = 1; 1502 } 1503 } else 1504 sp->se_nspace = 0; 1505 1506 /* 1507 * fork(), not vfork() -- we can't afford to block. 1508 */ 1509 if ((pid = fork()) == -1) { 1510 emergency("can't fork for getty on port %s: %m", sp->se_device); 1511 return -1; 1512 } 1513 1514 if (pid) 1515 return pid; 1516 1517 if (too_quick) { 1518 warning("getty repeating too quickly on port %s, sleeping %d secs", 1519 sp->se_device, GETTY_SLEEP); 1520 sleep((unsigned) GETTY_SLEEP); 1521 } 1522 1523 if (sp->se_window) { 1524 start_window_system(sp); 1525 sleep(WINDOW_WAIT); 1526 } 1527 1528 sigemptyset(&mask); 1529 sigprocmask(SIG_SETMASK, &mask, NULL); 1530 1531 #ifdef LOGIN_CAP 1532 setprocresources(RESOURCE_GETTY); 1533 #endif 1534 if (sp->se_type) { 1535 /* Don't use malloc after fork */ 1536 strcpy(term, "TERM="); 1537 strlcat(term, sp->se_type, sizeof(term)); 1538 env[0] = term; 1539 env[1] = NULL; 1540 } else 1541 env[0] = NULL; 1542 execve(sp->se_getty_argv[0], sp->se_getty_argv, env); 1543 stall("can't exec getty '%s' for port %s: %m", 1544 sp->se_getty_argv[0], sp->se_device); 1545 _exit(1); 1546 } 1547 1548 /* 1549 * Return 1 if the session is defined as "onifexists" 1550 * or "onifconsole" and the device node does not exist. 1551 */ 1552 static int 1553 session_has_no_tty(session_t *sp) 1554 { 1555 int fd; 1556 1557 if ((sp->se_flags & SE_IFEXISTS) == 0 && 1558 (sp->se_flags & SE_IFCONSOLE) == 0) 1559 return (0); 1560 1561 fd = open(sp->se_device, O_RDONLY | O_NONBLOCK, 0); 1562 if (fd < 0) { 1563 if (errno == ENOENT) 1564 return (1); 1565 return (0); 1566 } 1567 1568 close(fd); 1569 return (0); 1570 } 1571 1572 /* 1573 * Collect exit status for a child. 1574 * If an exiting login, start a new login running. 1575 */ 1576 static void 1577 collect_child(pid_t pid) 1578 { 1579 session_t *sp, *sprev, *snext; 1580 1581 if (! sessions) 1582 return; 1583 1584 if (! (sp = find_session(pid))) 1585 return; 1586 1587 del_session(sp); 1588 sp->se_process = 0; 1589 1590 if (sp->se_flags & SE_SHUTDOWN || 1591 session_has_no_tty(sp)) { 1592 if ((sprev = sp->se_prev) != NULL) 1593 sprev->se_next = sp->se_next; 1594 else 1595 sessions = sp->se_next; 1596 if ((snext = sp->se_next) != NULL) 1597 snext->se_prev = sp->se_prev; 1598 free_session(sp); 1599 return; 1600 } 1601 1602 if ((pid = start_getty(sp)) == -1) { 1603 /* serious trouble */ 1604 requested_transition = clean_ttys; 1605 return; 1606 } 1607 1608 sp->se_process = pid; 1609 sp->se_started = time((time_t *) 0); 1610 add_session(sp); 1611 } 1612 1613 static const char * 1614 get_current_state(void) 1615 { 1616 1617 if (current_state == single_user) 1618 return ("single-user"); 1619 if (current_state == runcom) 1620 return ("runcom"); 1621 if (current_state == read_ttys) 1622 return ("read-ttys"); 1623 if (current_state == multi_user) 1624 return ("multi-user"); 1625 if (current_state == clean_ttys) 1626 return ("clean-ttys"); 1627 if (current_state == catatonia) 1628 return ("catatonia"); 1629 if (current_state == death) 1630 return ("death"); 1631 if (current_state == death_single) 1632 return ("death-single"); 1633 return ("unknown"); 1634 } 1635 1636 static void 1637 boottrace_transition(int sig) 1638 { 1639 const char *action; 1640 1641 switch (sig) { 1642 case SIGUSR2: 1643 action = "halt & poweroff"; 1644 break; 1645 case SIGUSR1: 1646 action = "halt"; 1647 break; 1648 case SIGINT: 1649 action = "reboot"; 1650 break; 1651 case SIGWINCH: 1652 action = "powercycle"; 1653 break; 1654 case SIGTERM: 1655 action = Reboot ? "reboot" : "single-user"; 1656 break; 1657 default: 1658 BOOTTRACE("signal %d from %s", sig, get_current_state()); 1659 return; 1660 } 1661 1662 /* Trace the shutdown reason. */ 1663 SHUTTRACE("%s from %s", action, get_current_state()); 1664 } 1665 1666 /* 1667 * Catch a signal and request a state transition. 1668 */ 1669 static void 1670 transition_handler(int sig) 1671 { 1672 1673 boottrace_transition(sig); 1674 switch (sig) { 1675 case SIGHUP: 1676 if (current_state == read_ttys || current_state == multi_user || 1677 current_state == clean_ttys || current_state == catatonia) 1678 requested_transition = clean_ttys; 1679 break; 1680 case SIGUSR2: 1681 howto = RB_POWEROFF; 1682 case SIGUSR1: 1683 howto |= RB_HALT; 1684 case SIGWINCH: 1685 case SIGINT: 1686 if (sig == SIGWINCH) 1687 howto |= RB_POWERCYCLE; 1688 Reboot = true; 1689 case SIGTERM: 1690 if (current_state == read_ttys || current_state == multi_user || 1691 current_state == clean_ttys || current_state == catatonia) 1692 requested_transition = death; 1693 else 1694 requested_transition = death_single; 1695 break; 1696 case SIGTSTP: 1697 if (current_state == runcom || current_state == read_ttys || 1698 current_state == clean_ttys || 1699 current_state == multi_user || current_state == catatonia) 1700 requested_transition = catatonia; 1701 break; 1702 case SIGEMT: 1703 requested_transition = reroot; 1704 break; 1705 default: 1706 requested_transition = 0; 1707 break; 1708 } 1709 } 1710 1711 /* 1712 * Take the system multiuser. 1713 */ 1714 static state_func_t 1715 multi_user(void) 1716 { 1717 static bool inmultiuser = false; 1718 pid_t pid; 1719 session_t *sp; 1720 1721 requested_transition = 0; 1722 1723 /* 1724 * If the administrator has not set the security level to -1 1725 * to indicate that the kernel should not run multiuser in secure 1726 * mode, and the run script has not set a higher level of security 1727 * than level 1, then put the kernel into secure mode. 1728 */ 1729 if (getsecuritylevel() == 0) 1730 setsecuritylevel(1); 1731 1732 for (sp = sessions; sp; sp = sp->se_next) { 1733 if (sp->se_process) 1734 continue; 1735 if (session_has_no_tty(sp)) 1736 continue; 1737 if ((pid = start_getty(sp)) == -1) { 1738 /* serious trouble */ 1739 requested_transition = clean_ttys; 1740 break; 1741 } 1742 sp->se_process = pid; 1743 sp->se_started = time((time_t *) 0); 1744 add_session(sp); 1745 } 1746 1747 if (requested_transition == 0 && !inmultiuser) { 1748 inmultiuser = true; 1749 /* This marks the change from boot-time tracing to run-time. */ 1750 RUNTRACE("multi-user start"); 1751 } 1752 while (!requested_transition) 1753 if ((pid = waitpid(-1, (int *) 0, 0)) != -1) 1754 collect_child(pid); 1755 1756 return (state_func_t) requested_transition; 1757 } 1758 1759 /* 1760 * This is an (n*2)+(n^2) algorithm. We hope it isn't run often... 1761 */ 1762 static state_func_t 1763 clean_ttys(void) 1764 { 1765 session_t *sp, *sprev; 1766 struct ttyent *typ; 1767 int devlen; 1768 char *old_getty, *old_window, *old_type; 1769 1770 /* 1771 * mark all sessions for death, (!SE_PRESENT) 1772 * as we find or create new ones they'll be marked as keepers, 1773 * we'll later nuke all the ones not found in /etc/ttys 1774 */ 1775 for (sp = sessions; sp != NULL; sp = sp->se_next) 1776 sp->se_flags &= ~SE_PRESENT; 1777 1778 devlen = sizeof(_PATH_DEV) - 1; 1779 while ((typ = getttyent()) != NULL) { 1780 for (sprev = 0, sp = sessions; sp; sprev = sp, sp = sp->se_next) 1781 if (strcmp(typ->ty_name, sp->se_device + devlen) == 0) 1782 break; 1783 1784 if (sp) { 1785 /* we want this one to live */ 1786 sp->se_flags |= SE_PRESENT; 1787 if ((typ->ty_status & TTY_ON) == 0 || 1788 typ->ty_getty == 0) { 1789 sp->se_flags |= SE_SHUTDOWN; 1790 kill(sp->se_process, SIGHUP); 1791 continue; 1792 } 1793 sp->se_flags &= ~SE_SHUTDOWN; 1794 old_getty = sp->se_getty ? strdup(sp->se_getty) : 0; 1795 old_window = sp->se_window ? strdup(sp->se_window) : 0; 1796 old_type = sp->se_type ? strdup(sp->se_type) : 0; 1797 if (setupargv(sp, typ) == 0) { 1798 warning("can't parse getty for port %s", 1799 sp->se_device); 1800 sp->se_flags |= SE_SHUTDOWN; 1801 kill(sp->se_process, SIGHUP); 1802 } 1803 else if ( !old_getty 1804 || (!old_type && sp->se_type) 1805 || (old_type && !sp->se_type) 1806 || (!old_window && sp->se_window) 1807 || (old_window && !sp->se_window) 1808 || (strcmp(old_getty, sp->se_getty) != 0) 1809 || (old_window && strcmp(old_window, sp->se_window) != 0) 1810 || (old_type && strcmp(old_type, sp->se_type) != 0) 1811 ) { 1812 /* Don't set SE_SHUTDOWN here */ 1813 sp->se_nspace = 0; 1814 sp->se_started = 0; 1815 kill(sp->se_process, SIGHUP); 1816 } 1817 if (old_getty) 1818 free(old_getty); 1819 if (old_window) 1820 free(old_window); 1821 if (old_type) 1822 free(old_type); 1823 continue; 1824 } 1825 1826 new_session(sprev, typ); 1827 } 1828 1829 endttyent(); 1830 1831 /* 1832 * sweep through and kill all deleted sessions 1833 * ones who's /etc/ttys line was deleted (SE_PRESENT unset) 1834 */ 1835 for (sp = sessions; sp != NULL; sp = sp->se_next) { 1836 if ((sp->se_flags & SE_PRESENT) == 0) { 1837 sp->se_flags |= SE_SHUTDOWN; 1838 kill(sp->se_process, SIGHUP); 1839 } 1840 } 1841 1842 return (state_func_t) multi_user; 1843 } 1844 1845 /* 1846 * Block further logins. 1847 */ 1848 static state_func_t 1849 catatonia(void) 1850 { 1851 session_t *sp; 1852 1853 for (sp = sessions; sp; sp = sp->se_next) 1854 sp->se_flags |= SE_SHUTDOWN; 1855 1856 return (state_func_t) multi_user; 1857 } 1858 1859 /* 1860 * Note SIGALRM. 1861 */ 1862 static void 1863 alrm_handler(int sig) 1864 { 1865 1866 (void)sig; 1867 clang = true; 1868 } 1869 1870 /* 1871 * Bring the system down to single user. 1872 */ 1873 static state_func_t 1874 death(void) 1875 { 1876 int block, blocked; 1877 size_t len; 1878 1879 /* Temporarily block suspend. */ 1880 len = sizeof(blocked); 1881 block = 1; 1882 if (sysctlbyname("kern.suspend_blocked", &blocked, &len, 1883 &block, sizeof(block)) == -1) 1884 blocked = 0; 1885 1886 /* 1887 * Also revoke the TTY here. Because runshutdown() may reopen 1888 * the TTY whose getty we're killing here, there is no guarantee 1889 * runshutdown() will perform the initial open() call, causing 1890 * the terminal attributes to be misconfigured. 1891 */ 1892 revoke_ttys(); 1893 1894 /* Try to run the rc.shutdown script within a period of time */ 1895 runshutdown(); 1896 1897 /* Unblock suspend if we blocked it. */ 1898 if (!blocked) 1899 sysctlbyname("kern.suspend_blocked", NULL, NULL, 1900 &blocked, sizeof(blocked)); 1901 1902 return (state_func_t) death_single; 1903 } 1904 1905 /* 1906 * Do what is necessary to reinitialize single user mode or reboot 1907 * from an incomplete state. 1908 */ 1909 static state_func_t 1910 death_single(void) 1911 { 1912 int i; 1913 pid_t pid; 1914 static const int death_sigs[2] = { SIGTERM, SIGKILL }; 1915 1916 revoke(_PATH_CONSOLE); 1917 1918 BOOTTRACE("start killing user processes"); 1919 for (i = 0; i < 2; ++i) { 1920 if (kill(-1, death_sigs[i]) == -1 && errno == ESRCH) 1921 return (state_func_t) single_user; 1922 1923 clang = false; 1924 alarm(DEATH_WATCH); 1925 do 1926 if ((pid = waitpid(-1, (int *)0, 0)) != -1) 1927 collect_child(pid); 1928 while (!clang && errno != ECHILD); 1929 1930 if (errno == ECHILD) 1931 return (state_func_t) single_user; 1932 } 1933 1934 warning("some processes would not die; ps axl advised"); 1935 1936 return (state_func_t) single_user; 1937 } 1938 1939 static void 1940 revoke_ttys(void) 1941 { 1942 session_t *sp; 1943 1944 for (sp = sessions; sp; sp = sp->se_next) { 1945 sp->se_flags |= SE_SHUTDOWN; 1946 kill(sp->se_process, SIGHUP); 1947 revoke(sp->se_device); 1948 } 1949 } 1950 1951 /* 1952 * Run the system shutdown script. 1953 * 1954 * Exit codes: XXX I should document more 1955 * -2 shutdown script terminated abnormally 1956 * -1 fatal error - can't run script 1957 * 0 good. 1958 * >0 some error (exit code) 1959 */ 1960 static int 1961 runshutdown(void) 1962 { 1963 pid_t pid, wpid; 1964 int status; 1965 int shutdowntimeout; 1966 size_t len; 1967 char *argv[SCRIPT_ARGV_SIZE]; 1968 struct stat sb; 1969 1970 BOOTTRACE("init(8): start rc.shutdown"); 1971 1972 /* 1973 * rc.shutdown is optional, so to prevent any unnecessary 1974 * complaints from the shell we simply don't run it if the 1975 * file does not exist. If the stat() here fails for other 1976 * reasons, we'll let the shell complain. 1977 */ 1978 if (stat(_PATH_RUNDOWN, &sb) == -1 && errno == ENOENT) 1979 return 0; 1980 1981 if ((pid = fork()) == 0) { 1982 char _reboot[] = "reboot"; 1983 char _single[] = "single"; 1984 char _path_rundown[] = _PATH_RUNDOWN; 1985 1986 argv[0] = _path_rundown; 1987 argv[1] = Reboot ? _reboot : _single; 1988 argv[2] = NULL; 1989 1990 execute_script(argv); 1991 _exit(1); /* force single user mode */ 1992 } 1993 1994 if (pid == -1) { 1995 emergency("can't fork for %s: %m", _PATH_RUNDOWN); 1996 while (waitpid(-1, (int *) 0, WNOHANG) > 0) 1997 continue; 1998 sleep(STALL_TIMEOUT); 1999 return -1; 2000 } 2001 2002 len = sizeof(shutdowntimeout); 2003 if (sysctlbyname("kern.init_shutdown_timeout", &shutdowntimeout, &len, 2004 NULL, 0) == -1 || shutdowntimeout < 2) 2005 shutdowntimeout = DEATH_SCRIPT; 2006 alarm(shutdowntimeout); 2007 clang = false; 2008 /* 2009 * Copied from single_user(). This is a bit paranoid. 2010 * Use the same ALRM handler. 2011 */ 2012 do { 2013 if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1) 2014 collect_child(wpid); 2015 if (clang) { 2016 /* we were waiting for the sub-shell */ 2017 kill(wpid, SIGTERM); 2018 warning("timeout expired for %s: %m; going to " 2019 "single user mode", _PATH_RUNDOWN); 2020 BOOTTRACE("rc.shutdown's %d sec timeout expired", 2021 shutdowntimeout); 2022 return -1; 2023 } 2024 if (wpid == -1) { 2025 if (errno == EINTR) 2026 continue; 2027 warning("wait for %s failed: %m; going to " 2028 "single user mode", _PATH_RUNDOWN); 2029 return -1; 2030 } 2031 if (wpid == pid && WIFSTOPPED(status)) { 2032 warning("init: %s stopped, restarting\n", 2033 _PATH_RUNDOWN); 2034 kill(pid, SIGCONT); 2035 wpid = -1; 2036 } 2037 } while (wpid != pid && !clang); 2038 2039 /* Turn off the alarm */ 2040 alarm(0); 2041 2042 if (WIFSIGNALED(status) && WTERMSIG(status) == SIGTERM && 2043 requested_transition == catatonia) { 2044 /* 2045 * /etc/rc.shutdown executed /sbin/reboot; 2046 * wait for the end quietly 2047 */ 2048 sigset_t s; 2049 2050 sigfillset(&s); 2051 for (;;) 2052 sigsuspend(&s); 2053 } 2054 2055 if (!WIFEXITED(status)) { 2056 warning("%s terminated abnormally, going to " 2057 "single user mode", _PATH_RUNDOWN); 2058 return -2; 2059 } 2060 2061 if ((status = WEXITSTATUS(status)) != 0) 2062 warning("%s returned status %d", _PATH_RUNDOWN, status); 2063 2064 return status; 2065 } 2066 2067 static char * 2068 strk(char *p) 2069 { 2070 static char *t; 2071 char *q; 2072 int c; 2073 2074 if (p) 2075 t = p; 2076 if (!t) 2077 return 0; 2078 2079 c = *t; 2080 while (c == ' ' || c == '\t' ) 2081 c = *++t; 2082 if (!c) { 2083 t = 0; 2084 return 0; 2085 } 2086 q = t; 2087 if (c == '\'') { 2088 c = *++t; 2089 q = t; 2090 while (c && c != '\'') 2091 c = *++t; 2092 if (!c) /* unterminated string */ 2093 q = t = 0; 2094 else 2095 *t++ = 0; 2096 } else { 2097 while (c && c != ' ' && c != '\t' ) 2098 c = *++t; 2099 *t++ = 0; 2100 if (!c) 2101 t = 0; 2102 } 2103 return q; 2104 } 2105 2106 #ifdef LOGIN_CAP 2107 static void 2108 setprocresources(const char *cname) 2109 { 2110 login_cap_t *lc; 2111 if ((lc = login_getclassbyname(cname, NULL)) != NULL) { 2112 setusercontext(lc, (struct passwd*)NULL, 0, 2113 LOGIN_SETENV | 2114 LOGIN_SETPRIORITY | LOGIN_SETRESOURCES | 2115 LOGIN_SETLOGINCLASS | LOGIN_SETCPUMASK); 2116 login_close(lc); 2117 } 2118 } 2119 #endif 2120 2121 /* 2122 * Run /etc/rc.final to execute scripts after all user processes have been 2123 * terminated. 2124 */ 2125 static void 2126 runfinal(void) 2127 { 2128 struct stat sb; 2129 pid_t other_pid, pid; 2130 sigset_t mask; 2131 2132 /* Avoid any surprises. */ 2133 alarm(0); 2134 2135 /* rc.final is optional. */ 2136 if (stat(_PATH_RUNFINAL, &sb) == -1 && errno == ENOENT) 2137 return; 2138 if (access(_PATH_RUNFINAL, X_OK) != 0) { 2139 warning("%s exists, but not executable", _PATH_RUNFINAL); 2140 return; 2141 } 2142 2143 pid = fork(); 2144 if (pid == 0) { 2145 /* 2146 * Reopen stdin/stdout/stderr so that scripts can write to 2147 * console. 2148 */ 2149 close(0); 2150 open(_PATH_DEVNULL, O_RDONLY); 2151 close(1); 2152 close(2); 2153 open_console(); 2154 dup2(1, 2); 2155 sigemptyset(&mask); 2156 sigprocmask(SIG_SETMASK, &mask, NULL); 2157 signal(SIGCHLD, SIG_DFL); 2158 execl(_PATH_RUNFINAL, _PATH_RUNFINAL, NULL); 2159 perror("execl(" _PATH_RUNFINAL ") failed"); 2160 exit(1); 2161 } 2162 2163 /* Wait for rc.final script to exit */ 2164 while ((other_pid = waitpid(-1, NULL, 0)) != pid && other_pid > 0) { 2165 continue; 2166 } 2167 } 2168