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