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