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