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 static const char rcsid[] = 46 "$FreeBSD$"; 47 #endif /* not lint */ 48 49 #include <sys/param.h> 50 #include <sys/boottrace.h> 51 #include <sys/ioctl.h> 52 #include <sys/mman.h> 53 #include <sys/mount.h> 54 #include <sys/reboot.h> 55 #include <sys/stat.h> 56 #include <sys/sysctl.h> 57 #include <sys/uio.h> 58 #include <sys/wait.h> 59 60 #include <db.h> 61 #include <err.h> 62 #include <errno.h> 63 #include <fcntl.h> 64 #include <kenv.h> 65 #include <libutil.h> 66 #include <paths.h> 67 #include <signal.h> 68 #include <stdarg.h> 69 #include <stdbool.h> 70 #include <stdio.h> 71 #include <stdlib.h> 72 #include <string.h> 73 #include <syslog.h> 74 #include <time.h> 75 #include <ttyent.h> 76 #include <unistd.h> 77 78 #ifdef SECURE 79 #include <pwd.h> 80 #endif 81 82 #ifdef LOGIN_CAP 83 #include <login_cap.h> 84 #endif 85 86 #include "mntopts.h" 87 #include "pathnames.h" 88 89 /* 90 * Sleep times; used to prevent thrashing. 91 */ 92 #define GETTY_SPACING 5 /* N secs minimum getty spacing */ 93 #define GETTY_SLEEP 30 /* sleep N secs after spacing problem */ 94 #define GETTY_NSPACE 3 /* max. spacing count to bring reaction */ 95 #define WINDOW_WAIT 3 /* wait N secs after starting window */ 96 #define STALL_TIMEOUT 30 /* wait N secs after warning */ 97 #define DEATH_WATCH 10 /* wait N secs for procs to die */ 98 #define DEATH_SCRIPT 120 /* wait for 2min for /etc/rc.shutdown */ 99 #define RESOURCE_RC "daemon" 100 #define RESOURCE_WINDOW "default" 101 #define RESOURCE_GETTY "default" 102 #define SCRIPT_ARGV_SIZE 3 /* size of argv passed to execute_script, can be increased if needed */ 103 104 static void handle(sig_t, ...); 105 static void delset(sigset_t *, ...); 106 107 static void stall(const char *, ...) __printflike(1, 2); 108 static void warning(const char *, ...) __printflike(1, 2); 109 static void emergency(const char *, ...) __printflike(1, 2); 110 static void disaster(int); 111 static void revoke_ttys(void); 112 static int runshutdown(void); 113 static char *strk(char *); 114 static void runfinal(void); 115 116 /* 117 * We really need a recursive typedef... 118 * The following at least guarantees that the return type of (*state_t)() 119 * is sufficiently wide to hold a function pointer. 120 */ 121 typedef long (*state_func_t)(void); 122 typedef state_func_t (*state_t)(void); 123 124 static state_func_t single_user(void); 125 static state_func_t runcom(void); 126 static state_func_t read_ttys(void); 127 static state_func_t multi_user(void); 128 static state_func_t clean_ttys(void); 129 static state_func_t catatonia(void); 130 static state_func_t death(void); 131 static state_func_t death_single(void); 132 static state_func_t reroot(void); 133 static state_func_t reroot_phase_two(void); 134 135 static state_func_t run_script(const char *); 136 137 static enum { AUTOBOOT, FASTBOOT } runcom_mode = AUTOBOOT; 138 139 static bool Reboot = false; 140 static int howto = RB_AUTOBOOT; 141 142 static bool devfs = false; 143 static char *init_path_argv0; 144 145 static void transition(state_t); 146 static state_t requested_transition; 147 static state_t current_state = death_single; 148 149 static void execute_script(char *argv[]); 150 static void open_console(void); 151 static const char *get_shell(void); 152 static void replace_init(char *path); 153 static void write_stderr(const char *message); 154 155 typedef struct init_session { 156 pid_t se_process; /* controlling process */ 157 time_t se_started; /* used to avoid thrashing */ 158 int se_flags; /* status of session */ 159 #define SE_SHUTDOWN 0x1 /* session won't be restarted */ 160 #define SE_PRESENT 0x2 /* session is in /etc/ttys */ 161 #define SE_IFEXISTS 0x4 /* session defined as "onifexists" */ 162 #define SE_IFCONSOLE 0x8 /* session defined as "onifconsole" */ 163 int se_nspace; /* spacing count */ 164 char *se_device; /* filename of port */ 165 char *se_getty; /* what to run on that port */ 166 char *se_getty_argv_space; /* pre-parsed argument array space */ 167 char **se_getty_argv; /* pre-parsed argument array */ 168 char *se_window; /* window system (started only once) */ 169 char *se_window_argv_space; /* pre-parsed argument array space */ 170 char **se_window_argv; /* pre-parsed argument array */ 171 char *se_type; /* default terminal type */ 172 struct init_session *se_prev; 173 struct init_session *se_next; 174 } session_t; 175 176 static void free_session(session_t *); 177 static session_t *new_session(session_t *, struct ttyent *); 178 static session_t *sessions; 179 180 static char **construct_argv(char *); 181 static void start_window_system(session_t *); 182 static void collect_child(pid_t); 183 static pid_t start_getty(session_t *); 184 static void transition_handler(int); 185 static void alrm_handler(int); 186 static void setsecuritylevel(int); 187 static int getsecuritylevel(void); 188 static int setupargv(session_t *, struct ttyent *); 189 #ifdef LOGIN_CAP 190 static void setprocresources(const char *); 191 #endif 192 static bool clang; 193 194 static int start_session_db(void); 195 static void add_session(session_t *); 196 static void del_session(session_t *); 197 static session_t *find_session(pid_t); 198 static DB *session_db; 199 200 /* 201 * The mother of all processes. 202 */ 203 int 204 main(int argc, char *argv[]) 205 { 206 state_t initial_transition = runcom; 207 char kenv_value[PATH_MAX]; 208 int c, error; 209 struct sigaction sa; 210 sigset_t mask; 211 212 /* Dispose of random users. */ 213 if (getuid() != 0) 214 errx(1, "%s", strerror(EPERM)); 215 216 BOOTTRACE("init(8) starting..."); 217 218 /* System V users like to reexec init. */ 219 if (getpid() != 1) { 220 #ifdef COMPAT_SYSV_INIT 221 /* So give them what they want */ 222 if (argc > 1) { 223 if (strlen(argv[1]) == 1) { 224 char runlevel = *argv[1]; 225 int sig; 226 227 switch (runlevel) { 228 case '0': /* halt + poweroff */ 229 sig = SIGUSR2; 230 break; 231 case '1': /* single-user */ 232 sig = SIGTERM; 233 break; 234 case '6': /* reboot */ 235 sig = SIGINT; 236 break; 237 case 'c': /* block further logins */ 238 sig = SIGTSTP; 239 break; 240 case 'q': /* rescan /etc/ttys */ 241 sig = SIGHUP; 242 break; 243 case 'r': /* remount root */ 244 sig = SIGEMT; 245 break; 246 default: 247 goto invalid; 248 } 249 kill(1, sig); 250 _exit(0); 251 } else 252 invalid: 253 errx(1, "invalid run-level ``%s''", argv[1]); 254 } else 255 #endif 256 errx(1, "already running"); 257 } 258 259 init_path_argv0 = strdup(argv[0]); 260 if (init_path_argv0 == NULL) 261 err(1, "strdup"); 262 263 /* 264 * Note that this does NOT open a file... 265 * Does 'init' deserve its own facility number? 266 */ 267 openlog("init", LOG_CONS, LOG_AUTH); 268 269 /* 270 * Create an initial session. 271 */ 272 if (setsid() < 0 && (errno != EPERM || getsid(0) != 1)) 273 warning("initial setsid() failed: %m"); 274 275 /* 276 * Establish an initial user so that programs running 277 * single user do not freak out and die (like passwd). 278 */ 279 if (setlogin("root") < 0) 280 warning("setlogin() failed: %m"); 281 282 /* 283 * This code assumes that we always get arguments through flags, 284 * never through bits set in some random machine register. 285 */ 286 while ((c = getopt(argc, argv, "dsfr")) != -1) 287 switch (c) { 288 case 'd': 289 devfs = true; 290 break; 291 case 's': 292 initial_transition = single_user; 293 break; 294 case 'f': 295 runcom_mode = FASTBOOT; 296 break; 297 case 'r': 298 initial_transition = reroot_phase_two; 299 break; 300 default: 301 warning("unrecognized flag '-%c'", c); 302 break; 303 } 304 305 if (optind != argc) 306 warning("ignoring excess arguments"); 307 308 /* 309 * We catch or block signals rather than ignore them, 310 * so that they get reset on exec. 311 */ 312 handle(disaster, SIGABRT, SIGFPE, SIGILL, SIGSEGV, SIGBUS, SIGSYS, 313 SIGXCPU, SIGXFSZ, 0); 314 handle(transition_handler, SIGHUP, SIGINT, SIGEMT, SIGTERM, SIGTSTP, 315 SIGUSR1, SIGUSR2, SIGWINCH, 0); 316 handle(alrm_handler, SIGALRM, 0); 317 sigfillset(&mask); 318 delset(&mask, SIGABRT, SIGFPE, SIGILL, SIGSEGV, SIGBUS, SIGSYS, 319 SIGXCPU, SIGXFSZ, SIGHUP, SIGINT, SIGEMT, SIGTERM, SIGTSTP, 320 SIGALRM, SIGUSR1, SIGUSR2, SIGWINCH, 0); 321 sigprocmask(SIG_SETMASK, &mask, NULL); 322 sigemptyset(&sa.sa_mask); 323 sa.sa_flags = 0; 324 sa.sa_handler = SIG_IGN; 325 sigaction(SIGTTIN, &sa, NULL); 326 sigaction(SIGTTOU, &sa, NULL); 327 328 /* 329 * Paranoia. 330 */ 331 close(0); 332 close(1); 333 close(2); 334 335 if (kenv(KENV_GET, "init_exec", kenv_value, sizeof(kenv_value)) > 0) { 336 replace_init(kenv_value); 337 _exit(0); /* reboot */ 338 } 339 340 if (kenv(KENV_GET, "init_script", kenv_value, sizeof(kenv_value)) > 0) { 341 state_func_t next_transition; 342 343 if ((next_transition = run_script(kenv_value)) != NULL) 344 initial_transition = (state_t) next_transition; 345 } 346 347 if (kenv(KENV_GET, "init_chroot", kenv_value, sizeof(kenv_value)) > 0) { 348 if (chdir(kenv_value) != 0 || chroot(".") != 0) 349 warning("Can't chroot to %s: %m", kenv_value); 350 } 351 352 /* 353 * Additional check if devfs needs to be mounted: 354 * If "/" and "/dev" have the same device number, 355 * then it hasn't been mounted yet. 356 */ 357 if (!devfs) { 358 struct stat stst; 359 dev_t root_devno; 360 361 stat("/", &stst); 362 root_devno = stst.st_dev; 363 if (stat("/dev", &stst) != 0) 364 warning("Can't stat /dev: %m"); 365 else if (stst.st_dev == root_devno) 366 devfs = true; 367 } 368 369 if (devfs) { 370 struct iovec iov[4]; 371 char *s; 372 int i; 373 374 char _fstype[] = "fstype"; 375 char _devfs[] = "devfs"; 376 char _fspath[] = "fspath"; 377 char _path_dev[]= _PATH_DEV; 378 379 iov[0].iov_base = _fstype; 380 iov[0].iov_len = sizeof(_fstype); 381 iov[1].iov_base = _devfs; 382 iov[1].iov_len = sizeof(_devfs); 383 iov[2].iov_base = _fspath; 384 iov[2].iov_len = sizeof(_fspath); 385 /* 386 * Try to avoid the trailing slash in _PATH_DEV. 387 * Be *very* defensive. 388 */ 389 s = strdup(_PATH_DEV); 390 if (s != NULL) { 391 i = strlen(s); 392 if (i > 0 && s[i - 1] == '/') 393 s[i - 1] = '\0'; 394 iov[3].iov_base = s; 395 iov[3].iov_len = strlen(s) + 1; 396 } else { 397 iov[3].iov_base = _path_dev; 398 iov[3].iov_len = sizeof(_path_dev); 399 } 400 nmount(iov, 4, 0); 401 if (s != NULL) 402 free(s); 403 } 404 405 if (initial_transition != reroot_phase_two) { 406 /* 407 * Unmount reroot leftovers. This runs after init(8) 408 * gets reexecuted after reroot_phase_two() is done. 409 */ 410 error = unmount(_PATH_REROOT, MNT_FORCE); 411 if (error != 0 && errno != EINVAL) 412 warning("Cannot unmount %s: %m", _PATH_REROOT); 413 } 414 415 /* 416 * Start the state machine. 417 */ 418 transition(initial_transition); 419 420 /* 421 * Should never reach here. 422 */ 423 return 1; 424 } 425 426 /* 427 * Associate a function with a signal handler. 428 */ 429 static void 430 handle(sig_t handler, ...) 431 { 432 int sig; 433 struct sigaction sa; 434 sigset_t mask_everything; 435 va_list ap; 436 va_start(ap, handler); 437 438 sa.sa_handler = handler; 439 sigfillset(&mask_everything); 440 441 while ((sig = va_arg(ap, int)) != 0) { 442 sa.sa_mask = mask_everything; 443 /* XXX SA_RESTART? */ 444 sa.sa_flags = sig == SIGCHLD ? SA_NOCLDSTOP : 0; 445 sigaction(sig, &sa, NULL); 446 } 447 va_end(ap); 448 } 449 450 /* 451 * Delete a set of signals from a mask. 452 */ 453 static void 454 delset(sigset_t *maskp, ...) 455 { 456 int sig; 457 va_list ap; 458 va_start(ap, maskp); 459 460 while ((sig = va_arg(ap, int)) != 0) 461 sigdelset(maskp, sig); 462 va_end(ap); 463 } 464 465 /* 466 * Log a message and sleep for a while (to give someone an opportunity 467 * to read it and to save log or hardcopy output if the problem is chronic). 468 * NB: should send a message to the session logger to avoid blocking. 469 */ 470 static void 471 stall(const char *message, ...) 472 { 473 va_list ap; 474 va_start(ap, message); 475 476 vsyslog(LOG_ALERT, message, ap); 477 va_end(ap); 478 sleep(STALL_TIMEOUT); 479 } 480 481 /* 482 * Like stall(), but doesn't sleep. 483 * If cpp had variadic macros, the two functions could be #defines for another. 484 * NB: should send a message to the session logger to avoid blocking. 485 */ 486 static void 487 warning(const char *message, ...) 488 { 489 va_list ap; 490 va_start(ap, message); 491 492 vsyslog(LOG_ALERT, message, ap); 493 va_end(ap); 494 } 495 496 /* 497 * Log an emergency message. 498 * NB: should send a message to the session logger to avoid blocking. 499 */ 500 static void 501 emergency(const char *message, ...) 502 { 503 va_list ap; 504 va_start(ap, message); 505 506 vsyslog(LOG_EMERG, message, ap); 507 va_end(ap); 508 } 509 510 /* 511 * Catch an unexpected signal. 512 */ 513 static void 514 disaster(int sig) 515 { 516 517 emergency("fatal signal: %s", 518 (unsigned)sig < NSIG ? sys_siglist[sig] : "unknown signal"); 519 520 sleep(STALL_TIMEOUT); 521 _exit(sig); /* reboot */ 522 } 523 524 /* 525 * Get the security level of the kernel. 526 */ 527 static int 528 getsecuritylevel(void) 529 { 530 #ifdef KERN_SECURELVL 531 int name[2], curlevel; 532 size_t len; 533 534 name[0] = CTL_KERN; 535 name[1] = KERN_SECURELVL; 536 len = sizeof curlevel; 537 if (sysctl(name, 2, &curlevel, &len, NULL, 0) == -1) { 538 emergency("cannot get kernel security level: %m"); 539 return (-1); 540 } 541 return (curlevel); 542 #else 543 return (-1); 544 #endif 545 } 546 547 /* 548 * Set the security level of the kernel. 549 */ 550 static void 551 setsecuritylevel(int newlevel) 552 { 553 #ifdef KERN_SECURELVL 554 int name[2], curlevel; 555 556 curlevel = getsecuritylevel(); 557 if (newlevel == curlevel) 558 return; 559 name[0] = CTL_KERN; 560 name[1] = KERN_SECURELVL; 561 if (sysctl(name, 2, NULL, NULL, &newlevel, sizeof newlevel) == -1) { 562 emergency( 563 "cannot change kernel security level from %d to %d: %m", 564 curlevel, newlevel); 565 return; 566 } 567 #ifdef SECURE 568 warning("kernel security level changed from %d to %d", 569 curlevel, newlevel); 570 #endif 571 #endif 572 } 573 574 /* 575 * Change states in the finite state machine. 576 * The initial state is passed as an argument. 577 */ 578 static void 579 transition(state_t s) 580 { 581 582 current_state = s; 583 for (;;) 584 current_state = (state_t) (*current_state)(); 585 } 586 587 /* 588 * Start a session and allocate a controlling terminal. 589 * Only called by children of init after forking. 590 */ 591 static void 592 open_console(void) 593 { 594 int fd; 595 596 /* 597 * Try to open /dev/console. Open the device with O_NONBLOCK to 598 * prevent potential blocking on a carrier. 599 */ 600 revoke(_PATH_CONSOLE); 601 if ((fd = open(_PATH_CONSOLE, O_RDWR | O_NONBLOCK)) != -1) { 602 (void)fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) & ~O_NONBLOCK); 603 if (login_tty(fd) == 0) 604 return; 605 close(fd); 606 } 607 608 /* No luck. Log output to file if possible. */ 609 if ((fd = open(_PATH_DEVNULL, O_RDWR)) == -1) { 610 stall("cannot open null device."); 611 _exit(1); 612 } 613 if (fd != STDIN_FILENO) { 614 dup2(fd, STDIN_FILENO); 615 close(fd); 616 } 617 fd = open(_PATH_INITLOG, O_WRONLY | O_APPEND | O_CREAT, 0644); 618 if (fd == -1) 619 dup2(STDIN_FILENO, STDOUT_FILENO); 620 else if (fd != STDOUT_FILENO) { 621 dup2(fd, STDOUT_FILENO); 622 close(fd); 623 } 624 dup2(STDOUT_FILENO, STDERR_FILENO); 625 } 626 627 static const char * 628 get_shell(void) 629 { 630 static char kenv_value[PATH_MAX]; 631 632 if (kenv(KENV_GET, "init_shell", kenv_value, sizeof(kenv_value)) > 0) 633 return kenv_value; 634 else 635 return _PATH_BSHELL; 636 } 637 638 static void 639 write_stderr(const char *message) 640 { 641 642 write(STDERR_FILENO, message, strlen(message)); 643 } 644 645 static int 646 read_file(const char *path, void **bufp, size_t *bufsizep) 647 { 648 struct stat sb; 649 size_t bufsize; 650 void *buf; 651 ssize_t nbytes; 652 int error, fd; 653 654 fd = open(path, O_RDONLY); 655 if (fd < 0) { 656 emergency("%s: %m", path); 657 return (-1); 658 } 659 660 error = fstat(fd, &sb); 661 if (error != 0) { 662 emergency("fstat: %m"); 663 close(fd); 664 return (error); 665 } 666 667 bufsize = sb.st_size; 668 buf = malloc(bufsize); 669 if (buf == NULL) { 670 emergency("malloc: %m"); 671 close(fd); 672 return (error); 673 } 674 675 nbytes = read(fd, buf, bufsize); 676 if (nbytes != (ssize_t)bufsize) { 677 emergency("read: %m"); 678 close(fd); 679 free(buf); 680 return (error); 681 } 682 683 error = close(fd); 684 if (error != 0) { 685 emergency("close: %m"); 686 free(buf); 687 return (error); 688 } 689 690 *bufp = buf; 691 *bufsizep = bufsize; 692 693 return (0); 694 } 695 696 static int 697 create_file(const char *path, const void *buf, size_t bufsize) 698 { 699 ssize_t nbytes; 700 int error, fd; 701 702 fd = open(path, O_WRONLY | O_CREAT | O_EXCL, 0700); 703 if (fd < 0) { 704 emergency("%s: %m", path); 705 return (-1); 706 } 707 708 nbytes = write(fd, buf, bufsize); 709 if (nbytes != (ssize_t)bufsize) { 710 emergency("write: %m"); 711 close(fd); 712 return (-1); 713 } 714 715 error = close(fd); 716 if (error != 0) { 717 emergency("close: %m"); 718 return (-1); 719 } 720 721 return (0); 722 } 723 724 static int 725 mount_tmpfs(const char *fspath) 726 { 727 struct iovec *iov; 728 char errmsg[255]; 729 int error, iovlen; 730 731 iov = NULL; 732 iovlen = 0; 733 memset(errmsg, 0, sizeof(errmsg)); 734 build_iovec(&iov, &iovlen, "fstype", 735 __DECONST(void *, "tmpfs"), (size_t)-1); 736 build_iovec(&iov, &iovlen, "fspath", 737 __DECONST(void *, fspath), (size_t)-1); 738 build_iovec(&iov, &iovlen, "errmsg", 739 errmsg, sizeof(errmsg)); 740 741 error = nmount(iov, iovlen, 0); 742 if (error != 0) { 743 if (*errmsg != '\0') { 744 emergency("cannot mount tmpfs on %s: %s: %m", 745 fspath, errmsg); 746 } else { 747 emergency("cannot mount tmpfs on %s: %m", 748 fspath); 749 } 750 return (error); 751 } 752 return (0); 753 } 754 755 static state_func_t 756 reroot(void) 757 { 758 void *buf; 759 size_t bufsize; 760 int error; 761 762 buf = NULL; 763 bufsize = 0; 764 765 revoke_ttys(); 766 runshutdown(); 767 768 /* 769 * Make sure nobody can interfere with our scheme. 770 * Ignore ESRCH, which can apparently happen when 771 * there are no processes to kill. 772 */ 773 error = kill(-1, SIGKILL); 774 if (error != 0 && errno != ESRCH) { 775 emergency("kill(2) failed: %m"); 776 goto out; 777 } 778 779 /* 780 * Copy the init binary into tmpfs, so that we can unmount 781 * the old rootfs without committing suicide. 782 */ 783 error = read_file(init_path_argv0, &buf, &bufsize); 784 if (error != 0) 785 goto out; 786 error = mount_tmpfs(_PATH_REROOT); 787 if (error != 0) 788 goto out; 789 error = create_file(_PATH_REROOT_INIT, buf, bufsize); 790 if (error != 0) 791 goto out; 792 793 /* 794 * Execute the temporary init. 795 */ 796 execl(_PATH_REROOT_INIT, _PATH_REROOT_INIT, "-r", NULL); 797 emergency("cannot exec %s: %m", _PATH_REROOT_INIT); 798 799 out: 800 emergency("reroot failed; going to single user mode"); 801 free(buf); 802 return (state_func_t) single_user; 803 } 804 805 static state_func_t 806 reroot_phase_two(void) 807 { 808 char init_path[PATH_MAX], *path, *path_component; 809 size_t init_path_len; 810 int nbytes, error; 811 812 /* 813 * Ask the kernel to mount the new rootfs. 814 */ 815 error = reboot(RB_REROOT); 816 if (error != 0) { 817 emergency("RB_REBOOT failed: %m"); 818 goto out; 819 } 820 821 /* 822 * Figure out where the destination init(8) binary is. Note that 823 * the path could be different than what we've started with. Use 824 * the value from kenv, if set, or the one from sysctl otherwise. 825 * The latter defaults to a hardcoded value, but can be overridden 826 * by a build time option. 827 */ 828 nbytes = kenv(KENV_GET, "init_path", init_path, sizeof(init_path)); 829 if (nbytes <= 0) { 830 init_path_len = sizeof(init_path); 831 error = sysctlbyname("kern.init_path", 832 init_path, &init_path_len, NULL, 0); 833 if (error != 0) { 834 emergency("failed to retrieve kern.init_path: %m"); 835 goto out; 836 } 837 } 838 839 /* 840 * Repeat the init search logic from sys/kern/init_path.c 841 */ 842 path_component = init_path; 843 while ((path = strsep(&path_component, ":")) != NULL) { 844 /* 845 * Execute init(8) from the new rootfs. 846 */ 847 execl(path, path, NULL); 848 } 849 emergency("cannot exec init from %s: %m", init_path); 850 851 out: 852 emergency("reroot failed; going to single user mode"); 853 return (state_func_t) single_user; 854 } 855 856 /* 857 * Bring the system up single user. 858 */ 859 static state_func_t 860 single_user(void) 861 { 862 pid_t pid, wpid; 863 int status; 864 sigset_t mask; 865 const char *shell; 866 char *argv[2]; 867 struct timeval tv, tn; 868 #ifdef SECURE 869 struct ttyent *typ; 870 struct passwd *pp; 871 static const char banner[] = 872 "Enter root password, or ^D to go multi-user\n"; 873 char *clear, *password; 874 #endif 875 #ifdef DEBUGSHELL 876 char altshell[128]; 877 #endif 878 879 if (Reboot) { 880 /* Instead of going single user, let's reboot the machine */ 881 BOOTTRACE("shutting down the system"); 882 sync(); 883 /* Run scripts after all processes have been terminated. */ 884 runfinal(); 885 if (reboot(howto) == -1) { 886 emergency("reboot(%#x) failed, %m", howto); 887 _exit(1); /* panic and reboot */ 888 } 889 warning("reboot(%#x) returned", howto); 890 _exit(0); /* panic as well */ 891 } 892 893 BOOTTRACE("going to single user mode"); 894 shell = get_shell(); 895 896 if ((pid = fork()) == 0) { 897 /* 898 * Start the single user session. 899 */ 900 open_console(); 901 902 #ifdef SECURE 903 /* 904 * Check the root password. 905 * We don't care if the console is 'on' by default; 906 * it's the only tty that can be 'off' and 'secure'. 907 */ 908 typ = getttynam("console"); 909 pp = getpwnam("root"); 910 if (typ && (typ->ty_status & TTY_SECURE) == 0 && 911 pp && *pp->pw_passwd) { 912 write_stderr(banner); 913 for (;;) { 914 clear = getpass("Password:"); 915 if (clear == NULL || *clear == '\0') 916 _exit(0); 917 password = crypt(clear, pp->pw_passwd); 918 explicit_bzero(clear, _PASSWORD_LEN); 919 if (password != NULL && 920 strcmp(password, pp->pw_passwd) == 0) 921 break; 922 warning("single-user login failed\n"); 923 } 924 } 925 endttyent(); 926 endpwent(); 927 #endif /* SECURE */ 928 929 #ifdef DEBUGSHELL 930 { 931 char *cp = altshell; 932 int num; 933 934 #define SHREQUEST "Enter full pathname of shell or RETURN for " 935 write_stderr(SHREQUEST); 936 write_stderr(shell); 937 write_stderr(": "); 938 while ((num = read(STDIN_FILENO, cp, 1)) != -1 && 939 num != 0 && *cp != '\n' && cp < &altshell[127]) 940 cp++; 941 *cp = '\0'; 942 if (altshell[0] != '\0') 943 shell = altshell; 944 } 945 #endif /* DEBUGSHELL */ 946 947 /* 948 * Unblock signals. 949 * We catch all the interesting ones, 950 * and those are reset to SIG_DFL on exec. 951 */ 952 sigemptyset(&mask); 953 sigprocmask(SIG_SETMASK, &mask, NULL); 954 955 /* 956 * Fire off a shell. 957 * If the default one doesn't work, try the Bourne shell. 958 */ 959 960 char name[] = "-sh"; 961 962 argv[0] = name; 963 argv[1] = NULL; 964 execv(shell, argv); 965 emergency("can't exec %s for single user: %m", shell); 966 execv(_PATH_BSHELL, argv); 967 emergency("can't exec %s for single user: %m", _PATH_BSHELL); 968 sleep(STALL_TIMEOUT); 969 _exit(1); 970 } 971 972 if (pid == -1) { 973 /* 974 * We are seriously hosed. Do our best. 975 */ 976 emergency("can't fork single-user shell, trying again"); 977 while (waitpid(-1, (int *) 0, WNOHANG) > 0) 978 continue; 979 return (state_func_t) single_user; 980 } 981 982 requested_transition = 0; 983 do { 984 if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1) 985 collect_child(wpid); 986 if (wpid == -1) { 987 if (errno == EINTR) 988 continue; 989 warning("wait for single-user shell failed: %m; restarting"); 990 return (state_func_t) single_user; 991 } 992 if (wpid == pid && WIFSTOPPED(status)) { 993 warning("init: shell stopped, restarting\n"); 994 kill(pid, SIGCONT); 995 wpid = -1; 996 } 997 } while (wpid != pid && !requested_transition); 998 999 if (requested_transition) 1000 return (state_func_t) requested_transition; 1001 1002 if (!WIFEXITED(status)) { 1003 if (WTERMSIG(status) == SIGKILL) { 1004 /* 1005 * reboot(8) killed shell? 1006 */ 1007 warning("single user shell terminated."); 1008 gettimeofday(&tv, NULL); 1009 tn = tv; 1010 tv.tv_sec += STALL_TIMEOUT; 1011 while (tv.tv_sec > tn.tv_sec || (tv.tv_sec == 1012 tn.tv_sec && tv.tv_usec > tn.tv_usec)) { 1013 sleep(1); 1014 gettimeofday(&tn, NULL); 1015 } 1016 _exit(0); 1017 } else { 1018 warning("single user shell terminated, restarting"); 1019 return (state_func_t) single_user; 1020 } 1021 } 1022 1023 runcom_mode = FASTBOOT; 1024 return (state_func_t) runcom; 1025 } 1026 1027 /* 1028 * Run the system startup script. 1029 */ 1030 static state_func_t 1031 runcom(void) 1032 { 1033 state_func_t next_transition; 1034 1035 BOOTTRACE("/etc/rc starting..."); 1036 if ((next_transition = run_script(_PATH_RUNCOM)) != NULL) 1037 return next_transition; 1038 BOOTTRACE("/etc/rc finished"); 1039 1040 runcom_mode = AUTOBOOT; /* the default */ 1041 return (state_func_t) read_ttys; 1042 } 1043 1044 static void 1045 execute_script(char *argv[]) 1046 { 1047 struct sigaction sa; 1048 char* sh_argv[3 + SCRIPT_ARGV_SIZE]; 1049 const char *shell, *script; 1050 int error, sh_argv_len, i; 1051 1052 bzero(&sa, sizeof(sa)); 1053 sigemptyset(&sa.sa_mask); 1054 sa.sa_handler = SIG_IGN; 1055 sigaction(SIGTSTP, &sa, NULL); 1056 sigaction(SIGHUP, &sa, NULL); 1057 1058 open_console(); 1059 1060 sigprocmask(SIG_SETMASK, &sa.sa_mask, NULL); 1061 #ifdef LOGIN_CAP 1062 setprocresources(RESOURCE_RC); 1063 #endif 1064 1065 /* 1066 * Try to directly execute the script first. If it 1067 * fails, try the old method of passing the script path 1068 * to sh(1). Don't complain if it fails because of 1069 * the missing execute bit. 1070 */ 1071 script = argv[0]; 1072 error = access(script, X_OK); 1073 if (error == 0) { 1074 execv(script, argv); 1075 warning("can't directly exec %s: %m", script); 1076 } else if (errno != EACCES) { 1077 warning("can't access %s: %m", script); 1078 } 1079 1080 shell = get_shell(); 1081 sh_argv[0] = __DECONST(char*, shell); 1082 sh_argv_len = 1; 1083 #ifdef SECURE 1084 if (strcmp(shell, _PATH_BSHELL) == 0) { 1085 sh_argv[1] = __DECONST(char*, "-o"); 1086 sh_argv[2] = __DECONST(char*, "verify"); 1087 sh_argv_len = 3; 1088 } 1089 #endif 1090 for (i = 0; i != SCRIPT_ARGV_SIZE; ++i) 1091 sh_argv[i + sh_argv_len] = argv[i]; 1092 execv(shell, sh_argv); 1093 stall("can't exec %s for %s: %m", shell, script); 1094 } 1095 1096 /* 1097 * Execute binary, replacing init(8) as PID 1. 1098 */ 1099 static void 1100 replace_init(char *path) 1101 { 1102 char *argv[SCRIPT_ARGV_SIZE]; 1103 1104 argv[0] = path; 1105 argv[1] = NULL; 1106 1107 execute_script(argv); 1108 } 1109 1110 /* 1111 * Run a shell script. 1112 * Returns 0 on success, otherwise the next transition to enter: 1113 * - single_user if fork/execv/waitpid failed, or if the script 1114 * terminated with a signal or exit code != 0. 1115 * - death_single if a SIGTERM was delivered to init(8). 1116 */ 1117 static state_func_t 1118 run_script(const char *script) 1119 { 1120 pid_t pid, wpid; 1121 int status; 1122 char *argv[SCRIPT_ARGV_SIZE]; 1123 const char *shell; 1124 1125 shell = get_shell(); 1126 1127 if ((pid = fork()) == 0) { 1128 1129 char _autoboot[] = "autoboot"; 1130 1131 argv[0] = __DECONST(char *, script); 1132 argv[1] = runcom_mode == AUTOBOOT ? _autoboot : NULL; 1133 argv[2] = NULL; 1134 1135 execute_script(argv); 1136 sleep(STALL_TIMEOUT); 1137 _exit(1); /* force single user mode */ 1138 } 1139 1140 if (pid == -1) { 1141 emergency("can't fork for %s on %s: %m", shell, script); 1142 while (waitpid(-1, (int *) 0, WNOHANG) > 0) 1143 continue; 1144 sleep(STALL_TIMEOUT); 1145 return (state_func_t) single_user; 1146 } 1147 1148 /* 1149 * Copied from single_user(). This is a bit paranoid. 1150 */ 1151 requested_transition = 0; 1152 do { 1153 if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1) 1154 collect_child(wpid); 1155 if (requested_transition == death_single || 1156 requested_transition == reroot) 1157 return (state_func_t) requested_transition; 1158 if (wpid == -1) { 1159 if (errno == EINTR) 1160 continue; 1161 warning("wait for %s on %s failed: %m; going to " 1162 "single user mode", shell, script); 1163 return (state_func_t) single_user; 1164 } 1165 if (wpid == pid && WIFSTOPPED(status)) { 1166 warning("init: %s on %s stopped, restarting\n", 1167 shell, script); 1168 kill(pid, SIGCONT); 1169 wpid = -1; 1170 } 1171 } while (wpid != pid); 1172 1173 if (WIFSIGNALED(status) && WTERMSIG(status) == SIGTERM && 1174 requested_transition == catatonia) { 1175 /* /etc/rc executed /sbin/reboot; wait for the end quietly */ 1176 sigset_t s; 1177 1178 sigfillset(&s); 1179 for (;;) 1180 sigsuspend(&s); 1181 } 1182 1183 if (!WIFEXITED(status)) { 1184 warning("%s on %s terminated abnormally, going to single " 1185 "user mode", shell, script); 1186 return (state_func_t) single_user; 1187 } 1188 1189 if (WEXITSTATUS(status)) 1190 return (state_func_t) single_user; 1191 1192 return (state_func_t) 0; 1193 } 1194 1195 /* 1196 * Open the session database. 1197 * 1198 * NB: We could pass in the size here; is it necessary? 1199 */ 1200 static int 1201 start_session_db(void) 1202 { 1203 if (session_db && (*session_db->close)(session_db)) 1204 emergency("session database close: %m"); 1205 if ((session_db = dbopen(NULL, O_RDWR, 0, DB_HASH, NULL)) == NULL) { 1206 emergency("session database open: %m"); 1207 return (1); 1208 } 1209 return (0); 1210 1211 } 1212 1213 /* 1214 * Add a new login session. 1215 */ 1216 static void 1217 add_session(session_t *sp) 1218 { 1219 DBT key; 1220 DBT data; 1221 1222 key.data = &sp->se_process; 1223 key.size = sizeof sp->se_process; 1224 data.data = &sp; 1225 data.size = sizeof sp; 1226 1227 if ((*session_db->put)(session_db, &key, &data, 0)) 1228 emergency("insert %d: %m", sp->se_process); 1229 } 1230 1231 /* 1232 * Delete an old login session. 1233 */ 1234 static void 1235 del_session(session_t *sp) 1236 { 1237 DBT key; 1238 1239 key.data = &sp->se_process; 1240 key.size = sizeof sp->se_process; 1241 1242 if ((*session_db->del)(session_db, &key, 0)) 1243 emergency("delete %d: %m", sp->se_process); 1244 } 1245 1246 /* 1247 * Look up a login session by pid. 1248 */ 1249 static session_t * 1250 find_session(pid_t pid) 1251 { 1252 DBT key; 1253 DBT data; 1254 session_t *ret; 1255 1256 key.data = &pid; 1257 key.size = sizeof pid; 1258 if ((*session_db->get)(session_db, &key, &data, 0) != 0) 1259 return 0; 1260 bcopy(data.data, (char *)&ret, sizeof(ret)); 1261 return ret; 1262 } 1263 1264 /* 1265 * Construct an argument vector from a command line. 1266 */ 1267 static char ** 1268 construct_argv(char *command) 1269 { 1270 int argc = 0; 1271 char **argv = (char **) malloc(((strlen(command) + 1) / 2 + 1) 1272 * sizeof (char *)); 1273 1274 if ((argv[argc++] = strk(command)) == NULL) { 1275 free(argv); 1276 return (NULL); 1277 } 1278 while ((argv[argc++] = strk((char *) 0)) != NULL) 1279 continue; 1280 return argv; 1281 } 1282 1283 /* 1284 * Deallocate a session descriptor. 1285 */ 1286 static void 1287 free_session(session_t *sp) 1288 { 1289 free(sp->se_device); 1290 if (sp->se_getty) { 1291 free(sp->se_getty); 1292 free(sp->se_getty_argv_space); 1293 free(sp->se_getty_argv); 1294 } 1295 if (sp->se_window) { 1296 free(sp->se_window); 1297 free(sp->se_window_argv_space); 1298 free(sp->se_window_argv); 1299 } 1300 if (sp->se_type) 1301 free(sp->se_type); 1302 free(sp); 1303 } 1304 1305 /* 1306 * Allocate a new session descriptor. 1307 * Mark it SE_PRESENT. 1308 */ 1309 static session_t * 1310 new_session(session_t *sprev, struct ttyent *typ) 1311 { 1312 session_t *sp; 1313 1314 if ((typ->ty_status & TTY_ON) == 0 || 1315 typ->ty_name == 0 || 1316 typ->ty_getty == 0) 1317 return 0; 1318 1319 sp = (session_t *) calloc(1, sizeof (session_t)); 1320 1321 sp->se_flags |= SE_PRESENT; 1322 1323 if ((typ->ty_status & TTY_IFEXISTS) != 0) 1324 sp->se_flags |= SE_IFEXISTS; 1325 1326 if ((typ->ty_status & TTY_IFCONSOLE) != 0) 1327 sp->se_flags |= SE_IFCONSOLE; 1328 1329 if (asprintf(&sp->se_device, "%s%s", _PATH_DEV, typ->ty_name) < 0) 1330 err(1, "asprintf"); 1331 1332 if (setupargv(sp, typ) == 0) { 1333 free_session(sp); 1334 return (0); 1335 } 1336 1337 sp->se_next = 0; 1338 if (sprev == NULL) { 1339 sessions = sp; 1340 sp->se_prev = 0; 1341 } else { 1342 sprev->se_next = sp; 1343 sp->se_prev = sprev; 1344 } 1345 1346 return sp; 1347 } 1348 1349 /* 1350 * Calculate getty and if useful window argv vectors. 1351 */ 1352 static int 1353 setupargv(session_t *sp, struct ttyent *typ) 1354 { 1355 1356 if (sp->se_getty) { 1357 free(sp->se_getty); 1358 free(sp->se_getty_argv_space); 1359 free(sp->se_getty_argv); 1360 } 1361 if (asprintf(&sp->se_getty, "%s %s", typ->ty_getty, typ->ty_name) < 0) 1362 err(1, "asprintf"); 1363 sp->se_getty_argv_space = strdup(sp->se_getty); 1364 sp->se_getty_argv = construct_argv(sp->se_getty_argv_space); 1365 if (sp->se_getty_argv == NULL) { 1366 warning("can't parse getty for port %s", sp->se_device); 1367 free(sp->se_getty); 1368 free(sp->se_getty_argv_space); 1369 sp->se_getty = sp->se_getty_argv_space = 0; 1370 return (0); 1371 } 1372 if (sp->se_window) { 1373 free(sp->se_window); 1374 free(sp->se_window_argv_space); 1375 free(sp->se_window_argv); 1376 } 1377 sp->se_window = sp->se_window_argv_space = 0; 1378 sp->se_window_argv = 0; 1379 if (typ->ty_window) { 1380 sp->se_window = strdup(typ->ty_window); 1381 sp->se_window_argv_space = strdup(sp->se_window); 1382 sp->se_window_argv = construct_argv(sp->se_window_argv_space); 1383 if (sp->se_window_argv == NULL) { 1384 warning("can't parse window for port %s", 1385 sp->se_device); 1386 free(sp->se_window_argv_space); 1387 free(sp->se_window); 1388 sp->se_window = sp->se_window_argv_space = 0; 1389 return (0); 1390 } 1391 } 1392 if (sp->se_type) 1393 free(sp->se_type); 1394 sp->se_type = typ->ty_type ? strdup(typ->ty_type) : 0; 1395 return (1); 1396 } 1397 1398 /* 1399 * Walk the list of ttys and create sessions for each active line. 1400 */ 1401 static state_func_t 1402 read_ttys(void) 1403 { 1404 session_t *sp, *snext; 1405 struct ttyent *typ; 1406 1407 /* 1408 * Destroy any previous session state. 1409 * There shouldn't be any, but just in case... 1410 */ 1411 for (sp = sessions; sp; sp = snext) { 1412 snext = sp->se_next; 1413 free_session(sp); 1414 } 1415 sessions = 0; 1416 if (start_session_db()) 1417 return (state_func_t) single_user; 1418 1419 /* 1420 * Allocate a session entry for each active port. 1421 * Note that sp starts at 0. 1422 */ 1423 while ((typ = getttyent()) != NULL) 1424 if ((snext = new_session(sp, typ)) != NULL) 1425 sp = snext; 1426 1427 endttyent(); 1428 1429 return (state_func_t) multi_user; 1430 } 1431 1432 /* 1433 * Start a window system running. 1434 */ 1435 static void 1436 start_window_system(session_t *sp) 1437 { 1438 pid_t pid; 1439 sigset_t mask; 1440 char term[64], *env[2]; 1441 int status; 1442 1443 if ((pid = fork()) == -1) { 1444 emergency("can't fork for window system on port %s: %m", 1445 sp->se_device); 1446 /* hope that getty fails and we can try again */ 1447 return; 1448 } 1449 if (pid) { 1450 waitpid(-1, &status, 0); 1451 return; 1452 } 1453 1454 /* reparent window process to the init to not make a zombie on exit */ 1455 if ((pid = fork()) == -1) { 1456 emergency("can't fork for window system on port %s: %m", 1457 sp->se_device); 1458 _exit(1); 1459 } 1460 if (pid) 1461 _exit(0); 1462 1463 sigemptyset(&mask); 1464 sigprocmask(SIG_SETMASK, &mask, NULL); 1465 1466 if (setsid() < 0) 1467 emergency("setsid failed (window) %m"); 1468 1469 #ifdef LOGIN_CAP 1470 setprocresources(RESOURCE_WINDOW); 1471 #endif 1472 if (sp->se_type) { 1473 /* Don't use malloc after fork */ 1474 strcpy(term, "TERM="); 1475 strlcat(term, sp->se_type, sizeof(term)); 1476 env[0] = term; 1477 env[1] = NULL; 1478 } 1479 else 1480 env[0] = NULL; 1481 execve(sp->se_window_argv[0], sp->se_window_argv, env); 1482 stall("can't exec window system '%s' for port %s: %m", 1483 sp->se_window_argv[0], sp->se_device); 1484 _exit(1); 1485 } 1486 1487 /* 1488 * Start a login session running. 1489 */ 1490 static pid_t 1491 start_getty(session_t *sp) 1492 { 1493 pid_t pid; 1494 sigset_t mask; 1495 time_t current_time = time((time_t *) 0); 1496 int too_quick = 0; 1497 char term[64], *env[2]; 1498 1499 if (current_time >= sp->se_started && 1500 current_time - sp->se_started < GETTY_SPACING) { 1501 if (++sp->se_nspace > GETTY_NSPACE) { 1502 sp->se_nspace = 0; 1503 too_quick = 1; 1504 } 1505 } else 1506 sp->se_nspace = 0; 1507 1508 /* 1509 * fork(), not vfork() -- we can't afford to block. 1510 */ 1511 if ((pid = fork()) == -1) { 1512 emergency("can't fork for getty on port %s: %m", sp->se_device); 1513 return -1; 1514 } 1515 1516 if (pid) 1517 return pid; 1518 1519 if (too_quick) { 1520 warning("getty repeating too quickly on port %s, sleeping %d secs", 1521 sp->se_device, GETTY_SLEEP); 1522 sleep((unsigned) GETTY_SLEEP); 1523 } 1524 1525 if (sp->se_window) { 1526 start_window_system(sp); 1527 sleep(WINDOW_WAIT); 1528 } 1529 1530 sigemptyset(&mask); 1531 sigprocmask(SIG_SETMASK, &mask, NULL); 1532 1533 #ifdef LOGIN_CAP 1534 setprocresources(RESOURCE_GETTY); 1535 #endif 1536 if (sp->se_type) { 1537 /* Don't use malloc after fork */ 1538 strcpy(term, "TERM="); 1539 strlcat(term, sp->se_type, sizeof(term)); 1540 env[0] = term; 1541 env[1] = NULL; 1542 } else 1543 env[0] = NULL; 1544 execve(sp->se_getty_argv[0], sp->se_getty_argv, env); 1545 stall("can't exec getty '%s' for port %s: %m", 1546 sp->se_getty_argv[0], sp->se_device); 1547 _exit(1); 1548 } 1549 1550 /* 1551 * Return 1 if the session is defined as "onifexists" 1552 * or "onifconsole" and the device node does not exist. 1553 */ 1554 static int 1555 session_has_no_tty(session_t *sp) 1556 { 1557 int fd; 1558 1559 if ((sp->se_flags & SE_IFEXISTS) == 0 && 1560 (sp->se_flags & SE_IFCONSOLE) == 0) 1561 return (0); 1562 1563 fd = open(sp->se_device, O_RDONLY | O_NONBLOCK, 0); 1564 if (fd < 0) { 1565 if (errno == ENOENT) 1566 return (1); 1567 return (0); 1568 } 1569 1570 close(fd); 1571 return (0); 1572 } 1573 1574 /* 1575 * Collect exit status for a child. 1576 * If an exiting login, start a new login running. 1577 */ 1578 static void 1579 collect_child(pid_t pid) 1580 { 1581 session_t *sp, *sprev, *snext; 1582 1583 if (! sessions) 1584 return; 1585 1586 if (! (sp = find_session(pid))) 1587 return; 1588 1589 del_session(sp); 1590 sp->se_process = 0; 1591 1592 if (sp->se_flags & SE_SHUTDOWN || 1593 session_has_no_tty(sp)) { 1594 if ((sprev = sp->se_prev) != NULL) 1595 sprev->se_next = sp->se_next; 1596 else 1597 sessions = sp->se_next; 1598 if ((snext = sp->se_next) != NULL) 1599 snext->se_prev = sp->se_prev; 1600 free_session(sp); 1601 return; 1602 } 1603 1604 if ((pid = start_getty(sp)) == -1) { 1605 /* serious trouble */ 1606 requested_transition = clean_ttys; 1607 return; 1608 } 1609 1610 sp->se_process = pid; 1611 sp->se_started = time((time_t *) 0); 1612 add_session(sp); 1613 } 1614 1615 static const char * 1616 get_current_state(void) 1617 { 1618 1619 if (current_state == single_user) 1620 return ("single-user"); 1621 if (current_state == runcom) 1622 return ("runcom"); 1623 if (current_state == read_ttys) 1624 return ("read-ttys"); 1625 if (current_state == multi_user) 1626 return ("multi-user"); 1627 if (current_state == clean_ttys) 1628 return ("clean-ttys"); 1629 if (current_state == catatonia) 1630 return ("catatonia"); 1631 if (current_state == death) 1632 return ("death"); 1633 if (current_state == death_single) 1634 return ("death-single"); 1635 return ("unknown"); 1636 } 1637 1638 static void 1639 boottrace_transition(int sig) 1640 { 1641 const char *action; 1642 1643 switch (sig) { 1644 case SIGUSR2: 1645 action = "halt & poweroff"; 1646 break; 1647 case SIGUSR1: 1648 action = "halt"; 1649 break; 1650 case SIGINT: 1651 action = "reboot"; 1652 break; 1653 case SIGWINCH: 1654 action = "powercycle"; 1655 break; 1656 case SIGTERM: 1657 action = Reboot ? "reboot" : "single-user"; 1658 break; 1659 default: 1660 BOOTTRACE("signal %d from %s", sig, get_current_state()); 1661 return; 1662 } 1663 1664 /* Trace the shutdown reason. */ 1665 SHUTTRACE("%s from %s", action, get_current_state()); 1666 } 1667 1668 /* 1669 * Catch a signal and request a state transition. 1670 */ 1671 static void 1672 transition_handler(int sig) 1673 { 1674 1675 boottrace_transition(sig); 1676 switch (sig) { 1677 case SIGHUP: 1678 if (current_state == read_ttys || current_state == multi_user || 1679 current_state == clean_ttys || current_state == catatonia) 1680 requested_transition = clean_ttys; 1681 break; 1682 case SIGUSR2: 1683 howto = RB_POWEROFF; 1684 case SIGUSR1: 1685 howto |= RB_HALT; 1686 case SIGWINCH: 1687 case SIGINT: 1688 if (sig == SIGWINCH) 1689 howto |= RB_POWERCYCLE; 1690 Reboot = true; 1691 case SIGTERM: 1692 if (current_state == read_ttys || current_state == multi_user || 1693 current_state == clean_ttys || current_state == catatonia) 1694 requested_transition = death; 1695 else 1696 requested_transition = death_single; 1697 break; 1698 case SIGTSTP: 1699 if (current_state == runcom || current_state == read_ttys || 1700 current_state == clean_ttys || 1701 current_state == multi_user || current_state == catatonia) 1702 requested_transition = catatonia; 1703 break; 1704 case SIGEMT: 1705 requested_transition = reroot; 1706 break; 1707 default: 1708 requested_transition = 0; 1709 break; 1710 } 1711 } 1712 1713 /* 1714 * Take the system multiuser. 1715 */ 1716 static state_func_t 1717 multi_user(void) 1718 { 1719 static bool inmultiuser = false; 1720 pid_t pid; 1721 session_t *sp; 1722 1723 requested_transition = 0; 1724 1725 /* 1726 * If the administrator has not set the security level to -1 1727 * to indicate that the kernel should not run multiuser in secure 1728 * mode, and the run script has not set a higher level of security 1729 * than level 1, then put the kernel into secure mode. 1730 */ 1731 if (getsecuritylevel() == 0) 1732 setsecuritylevel(1); 1733 1734 for (sp = sessions; sp; sp = sp->se_next) { 1735 if (sp->se_process) 1736 continue; 1737 if (session_has_no_tty(sp)) 1738 continue; 1739 if ((pid = start_getty(sp)) == -1) { 1740 /* serious trouble */ 1741 requested_transition = clean_ttys; 1742 break; 1743 } 1744 sp->se_process = pid; 1745 sp->se_started = time((time_t *) 0); 1746 add_session(sp); 1747 } 1748 1749 if (requested_transition == 0 && !inmultiuser) { 1750 inmultiuser = true; 1751 /* This marks the change from boot-time tracing to run-time. */ 1752 RUNTRACE("multi-user start"); 1753 } 1754 while (!requested_transition) 1755 if ((pid = waitpid(-1, (int *) 0, 0)) != -1) 1756 collect_child(pid); 1757 1758 return (state_func_t) requested_transition; 1759 } 1760 1761 /* 1762 * This is an (n*2)+(n^2) algorithm. We hope it isn't run often... 1763 */ 1764 static state_func_t 1765 clean_ttys(void) 1766 { 1767 session_t *sp, *sprev; 1768 struct ttyent *typ; 1769 int devlen; 1770 char *old_getty, *old_window, *old_type; 1771 1772 /* 1773 * mark all sessions for death, (!SE_PRESENT) 1774 * as we find or create new ones they'll be marked as keepers, 1775 * we'll later nuke all the ones not found in /etc/ttys 1776 */ 1777 for (sp = sessions; sp != NULL; sp = sp->se_next) 1778 sp->se_flags &= ~SE_PRESENT; 1779 1780 devlen = sizeof(_PATH_DEV) - 1; 1781 while ((typ = getttyent()) != NULL) { 1782 for (sprev = 0, sp = sessions; sp; sprev = sp, sp = sp->se_next) 1783 if (strcmp(typ->ty_name, sp->se_device + devlen) == 0) 1784 break; 1785 1786 if (sp) { 1787 /* we want this one to live */ 1788 sp->se_flags |= SE_PRESENT; 1789 if ((typ->ty_status & TTY_ON) == 0 || 1790 typ->ty_getty == 0) { 1791 sp->se_flags |= SE_SHUTDOWN; 1792 kill(sp->se_process, SIGHUP); 1793 continue; 1794 } 1795 sp->se_flags &= ~SE_SHUTDOWN; 1796 old_getty = sp->se_getty ? strdup(sp->se_getty) : 0; 1797 old_window = sp->se_window ? strdup(sp->se_window) : 0; 1798 old_type = sp->se_type ? strdup(sp->se_type) : 0; 1799 if (setupargv(sp, typ) == 0) { 1800 warning("can't parse getty for port %s", 1801 sp->se_device); 1802 sp->se_flags |= SE_SHUTDOWN; 1803 kill(sp->se_process, SIGHUP); 1804 } 1805 else if ( !old_getty 1806 || (!old_type && sp->se_type) 1807 || (old_type && !sp->se_type) 1808 || (!old_window && sp->se_window) 1809 || (old_window && !sp->se_window) 1810 || (strcmp(old_getty, sp->se_getty) != 0) 1811 || (old_window && strcmp(old_window, sp->se_window) != 0) 1812 || (old_type && strcmp(old_type, sp->se_type) != 0) 1813 ) { 1814 /* Don't set SE_SHUTDOWN here */ 1815 sp->se_nspace = 0; 1816 sp->se_started = 0; 1817 kill(sp->se_process, SIGHUP); 1818 } 1819 if (old_getty) 1820 free(old_getty); 1821 if (old_window) 1822 free(old_window); 1823 if (old_type) 1824 free(old_type); 1825 continue; 1826 } 1827 1828 new_session(sprev, typ); 1829 } 1830 1831 endttyent(); 1832 1833 /* 1834 * sweep through and kill all deleted sessions 1835 * ones who's /etc/ttys line was deleted (SE_PRESENT unset) 1836 */ 1837 for (sp = sessions; sp != NULL; sp = sp->se_next) { 1838 if ((sp->se_flags & SE_PRESENT) == 0) { 1839 sp->se_flags |= SE_SHUTDOWN; 1840 kill(sp->se_process, SIGHUP); 1841 } 1842 } 1843 1844 return (state_func_t) multi_user; 1845 } 1846 1847 /* 1848 * Block further logins. 1849 */ 1850 static state_func_t 1851 catatonia(void) 1852 { 1853 session_t *sp; 1854 1855 for (sp = sessions; sp; sp = sp->se_next) 1856 sp->se_flags |= SE_SHUTDOWN; 1857 1858 return (state_func_t) multi_user; 1859 } 1860 1861 /* 1862 * Note SIGALRM. 1863 */ 1864 static void 1865 alrm_handler(int sig) 1866 { 1867 1868 (void)sig; 1869 clang = true; 1870 } 1871 1872 /* 1873 * Bring the system down to single user. 1874 */ 1875 static state_func_t 1876 death(void) 1877 { 1878 int block, blocked; 1879 size_t len; 1880 1881 /* Temporarily block suspend. */ 1882 len = sizeof(blocked); 1883 block = 1; 1884 if (sysctlbyname("kern.suspend_blocked", &blocked, &len, 1885 &block, sizeof(block)) == -1) 1886 blocked = 0; 1887 1888 /* 1889 * Also revoke the TTY here. Because runshutdown() may reopen 1890 * the TTY whose getty we're killing here, there is no guarantee 1891 * runshutdown() will perform the initial open() call, causing 1892 * the terminal attributes to be misconfigured. 1893 */ 1894 revoke_ttys(); 1895 1896 /* Try to run the rc.shutdown script within a period of time */ 1897 runshutdown(); 1898 1899 /* Unblock suspend if we blocked it. */ 1900 if (!blocked) 1901 sysctlbyname("kern.suspend_blocked", NULL, NULL, 1902 &blocked, sizeof(blocked)); 1903 1904 return (state_func_t) death_single; 1905 } 1906 1907 /* 1908 * Do what is necessary to reinitialize single user mode or reboot 1909 * from an incomplete state. 1910 */ 1911 static state_func_t 1912 death_single(void) 1913 { 1914 int i; 1915 pid_t pid; 1916 static const int death_sigs[2] = { SIGTERM, SIGKILL }; 1917 1918 revoke(_PATH_CONSOLE); 1919 1920 BOOTTRACE("start killing user processes"); 1921 for (i = 0; i < 2; ++i) { 1922 if (kill(-1, death_sigs[i]) == -1 && errno == ESRCH) 1923 return (state_func_t) single_user; 1924 1925 clang = false; 1926 alarm(DEATH_WATCH); 1927 do 1928 if ((pid = waitpid(-1, (int *)0, 0)) != -1) 1929 collect_child(pid); 1930 while (!clang && errno != ECHILD); 1931 1932 if (errno == ECHILD) 1933 return (state_func_t) single_user; 1934 } 1935 1936 warning("some processes would not die; ps axl advised"); 1937 1938 return (state_func_t) single_user; 1939 } 1940 1941 static void 1942 revoke_ttys(void) 1943 { 1944 session_t *sp; 1945 1946 for (sp = sessions; sp; sp = sp->se_next) { 1947 sp->se_flags |= SE_SHUTDOWN; 1948 kill(sp->se_process, SIGHUP); 1949 revoke(sp->se_device); 1950 } 1951 } 1952 1953 /* 1954 * Run the system shutdown script. 1955 * 1956 * Exit codes: XXX I should document more 1957 * -2 shutdown script terminated abnormally 1958 * -1 fatal error - can't run script 1959 * 0 good. 1960 * >0 some error (exit code) 1961 */ 1962 static int 1963 runshutdown(void) 1964 { 1965 pid_t pid, wpid; 1966 int status; 1967 int shutdowntimeout; 1968 size_t len; 1969 char *argv[SCRIPT_ARGV_SIZE]; 1970 struct stat sb; 1971 1972 BOOTTRACE("init(8): start rc.shutdown"); 1973 1974 /* 1975 * rc.shutdown is optional, so to prevent any unnecessary 1976 * complaints from the shell we simply don't run it if the 1977 * file does not exist. If the stat() here fails for other 1978 * reasons, we'll let the shell complain. 1979 */ 1980 if (stat(_PATH_RUNDOWN, &sb) == -1 && errno == ENOENT) 1981 return 0; 1982 1983 if ((pid = fork()) == 0) { 1984 char _reboot[] = "reboot"; 1985 char _single[] = "single"; 1986 char _path_rundown[] = _PATH_RUNDOWN; 1987 1988 argv[0] = _path_rundown; 1989 argv[1] = Reboot ? _reboot : _single; 1990 argv[2] = NULL; 1991 1992 execute_script(argv); 1993 _exit(1); /* force single user mode */ 1994 } 1995 1996 if (pid == -1) { 1997 emergency("can't fork for %s: %m", _PATH_RUNDOWN); 1998 while (waitpid(-1, (int *) 0, WNOHANG) > 0) 1999 continue; 2000 sleep(STALL_TIMEOUT); 2001 return -1; 2002 } 2003 2004 len = sizeof(shutdowntimeout); 2005 if (sysctlbyname("kern.init_shutdown_timeout", &shutdowntimeout, &len, 2006 NULL, 0) == -1 || shutdowntimeout < 2) 2007 shutdowntimeout = DEATH_SCRIPT; 2008 alarm(shutdowntimeout); 2009 clang = false; 2010 /* 2011 * Copied from single_user(). This is a bit paranoid. 2012 * Use the same ALRM handler. 2013 */ 2014 do { 2015 if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1) 2016 collect_child(wpid); 2017 if (clang) { 2018 /* we were waiting for the sub-shell */ 2019 kill(wpid, SIGTERM); 2020 warning("timeout expired for %s: %m; going to " 2021 "single user mode", _PATH_RUNDOWN); 2022 BOOTTRACE("rc.shutdown's %d sec timeout expired", 2023 shutdowntimeout); 2024 return -1; 2025 } 2026 if (wpid == -1) { 2027 if (errno == EINTR) 2028 continue; 2029 warning("wait for %s failed: %m; going to " 2030 "single user mode", _PATH_RUNDOWN); 2031 return -1; 2032 } 2033 if (wpid == pid && WIFSTOPPED(status)) { 2034 warning("init: %s stopped, restarting\n", 2035 _PATH_RUNDOWN); 2036 kill(pid, SIGCONT); 2037 wpid = -1; 2038 } 2039 } while (wpid != pid && !clang); 2040 2041 /* Turn off the alarm */ 2042 alarm(0); 2043 2044 if (WIFSIGNALED(status) && WTERMSIG(status) == SIGTERM && 2045 requested_transition == catatonia) { 2046 /* 2047 * /etc/rc.shutdown executed /sbin/reboot; 2048 * wait for the end quietly 2049 */ 2050 sigset_t s; 2051 2052 sigfillset(&s); 2053 for (;;) 2054 sigsuspend(&s); 2055 } 2056 2057 if (!WIFEXITED(status)) { 2058 warning("%s terminated abnormally, going to " 2059 "single user mode", _PATH_RUNDOWN); 2060 return -2; 2061 } 2062 2063 if ((status = WEXITSTATUS(status)) != 0) 2064 warning("%s returned status %d", _PATH_RUNDOWN, status); 2065 2066 return status; 2067 } 2068 2069 static char * 2070 strk(char *p) 2071 { 2072 static char *t; 2073 char *q; 2074 int c; 2075 2076 if (p) 2077 t = p; 2078 if (!t) 2079 return 0; 2080 2081 c = *t; 2082 while (c == ' ' || c == '\t' ) 2083 c = *++t; 2084 if (!c) { 2085 t = 0; 2086 return 0; 2087 } 2088 q = t; 2089 if (c == '\'') { 2090 c = *++t; 2091 q = t; 2092 while (c && c != '\'') 2093 c = *++t; 2094 if (!c) /* unterminated string */ 2095 q = t = 0; 2096 else 2097 *t++ = 0; 2098 } else { 2099 while (c && c != ' ' && c != '\t' ) 2100 c = *++t; 2101 *t++ = 0; 2102 if (!c) 2103 t = 0; 2104 } 2105 return q; 2106 } 2107 2108 #ifdef LOGIN_CAP 2109 static void 2110 setprocresources(const char *cname) 2111 { 2112 login_cap_t *lc; 2113 if ((lc = login_getclassbyname(cname, NULL)) != NULL) { 2114 setusercontext(lc, (struct passwd*)NULL, 0, 2115 LOGIN_SETENV | 2116 LOGIN_SETPRIORITY | LOGIN_SETRESOURCES | 2117 LOGIN_SETLOGINCLASS | LOGIN_SETCPUMASK); 2118 login_close(lc); 2119 } 2120 } 2121 #endif 2122 2123 /* 2124 * Run /etc/rc.final to execute scripts after all user processes have been 2125 * terminated. 2126 */ 2127 static void 2128 runfinal(void) 2129 { 2130 struct stat sb; 2131 pid_t other_pid, pid; 2132 sigset_t mask; 2133 2134 /* Avoid any surprises. */ 2135 alarm(0); 2136 2137 /* rc.final is optional. */ 2138 if (stat(_PATH_RUNFINAL, &sb) == -1 && errno == ENOENT) 2139 return; 2140 if (access(_PATH_RUNFINAL, X_OK) != 0) { 2141 warning("%s exists, but not executable", _PATH_RUNFINAL); 2142 return; 2143 } 2144 2145 pid = fork(); 2146 if (pid == 0) { 2147 /* 2148 * Reopen stdin/stdout/stderr so that scripts can write to 2149 * console. 2150 */ 2151 close(0); 2152 open(_PATH_DEVNULL, O_RDONLY); 2153 close(1); 2154 close(2); 2155 open_console(); 2156 dup2(1, 2); 2157 sigemptyset(&mask); 2158 sigprocmask(SIG_SETMASK, &mask, NULL); 2159 signal(SIGCHLD, SIG_DFL); 2160 execl(_PATH_RUNFINAL, _PATH_RUNFINAL, NULL); 2161 perror("execl(" _PATH_RUNFINAL ") failed"); 2162 exit(1); 2163 } 2164 2165 /* Wait for rc.final script to exit */ 2166 while ((other_pid = waitpid(-1, NULL, 0)) != pid && other_pid > 0) { 2167 continue; 2168 } 2169 } 2170