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