1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Donn Seeley at Berkeley Software Design, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #ifndef lint 36 static const char copyright[] = 37 "@(#) Copyright (c) 1991, 1993\n\ 38 The Regents of the University of California. All rights reserved.\n"; 39 #endif /* not lint */ 40 41 #ifndef lint 42 #if 0 43 static char sccsid[] = "@(#)init.c 8.1 (Berkeley) 7/15/93"; 44 #endif 45 static const char rcsid[] = 46 "$FreeBSD$"; 47 #endif /* not lint */ 48 49 #include <sys/param.h> 50 #include <sys/ioctl.h> 51 #include <sys/mman.h> 52 #include <sys/mount.h> 53 #include <sys/sysctl.h> 54 #include <sys/wait.h> 55 #include <sys/stat.h> 56 #include <sys/uio.h> 57 58 #include <db.h> 59 #include <errno.h> 60 #include <fcntl.h> 61 #include <kenv.h> 62 #include <libutil.h> 63 #include <paths.h> 64 #include <signal.h> 65 #include <stdio.h> 66 #include <stdlib.h> 67 #include <string.h> 68 #include <syslog.h> 69 #include <time.h> 70 #include <ttyent.h> 71 #include <unistd.h> 72 #include <sys/reboot.h> 73 #include <err.h> 74 75 #include <stdarg.h> 76 77 #ifdef SECURE 78 #include <pwd.h> 79 #endif 80 81 #ifdef LOGIN_CAP 82 #include <login_cap.h> 83 #endif 84 85 #include "mntopts.h" 86 #include "pathnames.h" 87 88 /* 89 * Sleep times; used to prevent thrashing. 90 */ 91 #define GETTY_SPACING 5 /* N secs minimum getty spacing */ 92 #define GETTY_SLEEP 30 /* sleep N secs after spacing problem */ 93 #define GETTY_NSPACE 3 /* max. spacing count to bring reaction */ 94 #define WINDOW_WAIT 3 /* wait N secs after starting window */ 95 #define STALL_TIMEOUT 30 /* wait N secs after warning */ 96 #define DEATH_WATCH 10 /* wait N secs for procs to die */ 97 #define DEATH_SCRIPT 120 /* wait for 2min for /etc/rc.shutdown */ 98 #define RESOURCE_RC "daemon" 99 #define RESOURCE_WINDOW "default" 100 #define RESOURCE_GETTY "default" 101 102 static void handle(sig_t, ...); 103 static void delset(sigset_t *, ...); 104 105 static void stall(const char *, ...) __printflike(1, 2); 106 static void warning(const char *, ...) __printflike(1, 2); 107 static void emergency(const char *, ...) __printflike(1, 2); 108 static void disaster(int); 109 static void revoke_ttys(void); 110 static int runshutdown(void); 111 static char *strk(char *); 112 113 /* 114 * We really need a recursive typedef... 115 * The following at least guarantees that the return type of (*state_t)() 116 * is sufficiently wide to hold a function pointer. 117 */ 118 typedef long (*state_func_t)(void); 119 typedef state_func_t (*state_t)(void); 120 121 static state_func_t single_user(void); 122 static state_func_t runcom(void); 123 static state_func_t read_ttys(void); 124 static state_func_t multi_user(void); 125 static state_func_t clean_ttys(void); 126 static state_func_t catatonia(void); 127 static state_func_t death(void); 128 static state_func_t death_single(void); 129 static state_func_t reroot(void); 130 static state_func_t reroot_phase_two(void); 131 132 static state_func_t run_script(const char *); 133 134 static enum { AUTOBOOT, FASTBOOT } runcom_mode = AUTOBOOT; 135 #define FALSE 0 136 #define TRUE 1 137 138 static int Reboot = FALSE; 139 static int howto = RB_AUTOBOOT; 140 141 static int devfs; 142 static char *init_path_argv0; 143 144 static void transition(state_t); 145 static state_t requested_transition; 146 static state_t current_state = death_single; 147 148 static void execute_script(char *argv[]); 149 static void open_console(void); 150 static const char *get_shell(void); 151 static void replace_init(char *path); 152 static void write_stderr(const char *message); 153 154 typedef struct init_session { 155 pid_t se_process; /* controlling process */ 156 time_t se_started; /* used to avoid thrashing */ 157 int se_flags; /* status of session */ 158 #define SE_SHUTDOWN 0x1 /* session won't be restarted */ 159 #define SE_PRESENT 0x2 /* session is in /etc/ttys */ 160 #define SE_IFEXISTS 0x4 /* session defined as "onifexists" */ 161 #define SE_IFCONSOLE 0x8 /* session defined as "onifconsole" */ 162 int se_nspace; /* spacing count */ 163 char *se_device; /* filename of port */ 164 char *se_getty; /* what to run on that port */ 165 char *se_getty_argv_space; /* pre-parsed argument array space */ 166 char **se_getty_argv; /* pre-parsed argument array */ 167 char *se_window; /* window system (started only once) */ 168 char *se_window_argv_space; /* pre-parsed argument array space */ 169 char **se_window_argv; /* pre-parsed argument array */ 170 char *se_type; /* default terminal type */ 171 struct init_session *se_prev; 172 struct init_session *se_next; 173 } session_t; 174 175 static void free_session(session_t *); 176 static session_t *new_session(session_t *, struct ttyent *); 177 static session_t *sessions; 178 179 static char **construct_argv(char *); 180 static void start_window_system(session_t *); 181 static void collect_child(pid_t); 182 static pid_t start_getty(session_t *); 183 static void transition_handler(int); 184 static void alrm_handler(int); 185 static void setsecuritylevel(int); 186 static int getsecuritylevel(void); 187 static int setupargv(session_t *, struct ttyent *); 188 #ifdef LOGIN_CAP 189 static void setprocresources(const char *); 190 #endif 191 static int clang; 192 193 static int start_session_db(void); 194 static void add_session(session_t *); 195 static void del_session(session_t *); 196 static session_t *find_session(pid_t); 197 static DB *session_db; 198 199 /* 200 * The mother of all processes. 201 */ 202 int 203 main(int argc, char *argv[]) 204 { 205 state_t initial_transition = runcom; 206 char kenv_value[PATH_MAX]; 207 int c, error; 208 struct sigaction sa; 209 sigset_t mask; 210 211 /* Dispose of random users. */ 212 if (getuid() != 0) 213 errx(1, "%s", strerror(EPERM)); 214 215 /* System V users like to reexec init. */ 216 if (getpid() != 1) { 217 #ifdef COMPAT_SYSV_INIT 218 /* So give them what they want */ 219 if (argc > 1) { 220 if (strlen(argv[1]) == 1) { 221 char runlevel = *argv[1]; 222 int sig; 223 224 switch (runlevel) { 225 case '0': /* halt + poweroff */ 226 sig = SIGUSR2; 227 break; 228 case '1': /* single-user */ 229 sig = SIGTERM; 230 break; 231 case '6': /* reboot */ 232 sig = SIGINT; 233 break; 234 case 'c': /* block further logins */ 235 sig = SIGTSTP; 236 break; 237 case 'q': /* rescan /etc/ttys */ 238 sig = SIGHUP; 239 break; 240 case 'r': /* remount root */ 241 sig = SIGEMT; 242 break; 243 default: 244 goto invalid; 245 } 246 kill(1, sig); 247 _exit(0); 248 } else 249 invalid: 250 errx(1, "invalid run-level ``%s''", argv[1]); 251 } else 252 #endif 253 errx(1, "already running"); 254 } 255 256 init_path_argv0 = strdup(argv[0]); 257 if (init_path_argv0 == NULL) 258 err(1, "strdup"); 259 260 /* 261 * Note that this does NOT open a file... 262 * Does 'init' deserve its own facility number? 263 */ 264 openlog("init", LOG_CONS, LOG_AUTH); 265 266 /* 267 * Create an initial session. 268 */ 269 if (setsid() < 0 && (errno != EPERM || getsid(0) != 1)) 270 warning("initial setsid() failed: %m"); 271 272 /* 273 * Establish an initial user so that programs running 274 * single user do not freak out and die (like passwd). 275 */ 276 if (setlogin("root") < 0) 277 warning("setlogin() failed: %m"); 278 279 /* 280 * This code assumes that we always get arguments through flags, 281 * never through bits set in some random machine register. 282 */ 283 while ((c = getopt(argc, argv, "dsfr")) != -1) 284 switch (c) { 285 case 'd': 286 devfs = 1; 287 break; 288 case 's': 289 initial_transition = single_user; 290 break; 291 case 'f': 292 runcom_mode = FASTBOOT; 293 break; 294 case 'r': 295 initial_transition = reroot_phase_two; 296 break; 297 default: 298 warning("unrecognized flag '-%c'", c); 299 break; 300 } 301 302 if (optind != argc) 303 warning("ignoring excess arguments"); 304 305 /* 306 * We catch or block signals rather than ignore them, 307 * so that they get reset on exec. 308 */ 309 handle(disaster, SIGABRT, SIGFPE, SIGILL, SIGSEGV, SIGBUS, SIGSYS, 310 SIGXCPU, SIGXFSZ, 0); 311 handle(transition_handler, SIGHUP, SIGINT, SIGEMT, SIGTERM, SIGTSTP, 312 SIGUSR1, SIGUSR2, SIGWINCH, 0); 313 handle(alrm_handler, SIGALRM, 0); 314 sigfillset(&mask); 315 delset(&mask, SIGABRT, SIGFPE, SIGILL, SIGSEGV, SIGBUS, SIGSYS, 316 SIGXCPU, SIGXFSZ, SIGHUP, SIGINT, SIGEMT, SIGTERM, SIGTSTP, 317 SIGALRM, SIGUSR1, SIGUSR2, SIGWINCH, 0); 318 sigprocmask(SIG_SETMASK, &mask, NULL); 319 sigemptyset(&sa.sa_mask); 320 sa.sa_flags = 0; 321 sa.sa_handler = SIG_IGN; 322 sigaction(SIGTTIN, &sa, NULL); 323 sigaction(SIGTTOU, &sa, NULL); 324 325 /* 326 * Paranoia. 327 */ 328 close(0); 329 close(1); 330 close(2); 331 332 if (kenv(KENV_GET, "init_exec", kenv_value, sizeof(kenv_value)) > 0) { 333 replace_init(kenv_value); 334 _exit(0); /* reboot */ 335 } 336 337 if (kenv(KENV_GET, "init_script", kenv_value, sizeof(kenv_value)) > 0) { 338 state_func_t next_transition; 339 340 if ((next_transition = run_script(kenv_value)) != NULL) 341 initial_transition = (state_t) next_transition; 342 } 343 344 if (kenv(KENV_GET, "init_chroot", kenv_value, sizeof(kenv_value)) > 0) { 345 if (chdir(kenv_value) != 0 || chroot(".") != 0) 346 warning("Can't chroot to %s: %m", kenv_value); 347 } 348 349 /* 350 * Additional check if devfs needs to be mounted: 351 * If "/" and "/dev" have the same device number, 352 * then it hasn't been mounted yet. 353 */ 354 if (!devfs) { 355 struct stat stst; 356 dev_t root_devno; 357 358 stat("/", &stst); 359 root_devno = stst.st_dev; 360 if (stat("/dev", &stst) != 0) 361 warning("Can't stat /dev: %m"); 362 else if (stst.st_dev == root_devno) 363 devfs++; 364 } 365 366 if (devfs) { 367 struct iovec iov[4]; 368 char *s; 369 int i; 370 371 char _fstype[] = "fstype"; 372 char _devfs[] = "devfs"; 373 char _fspath[] = "fspath"; 374 char _path_dev[]= _PATH_DEV; 375 376 iov[0].iov_base = _fstype; 377 iov[0].iov_len = sizeof(_fstype); 378 iov[1].iov_base = _devfs; 379 iov[1].iov_len = sizeof(_devfs); 380 iov[2].iov_base = _fspath; 381 iov[2].iov_len = sizeof(_fspath); 382 /* 383 * Try to avoid the trailing slash in _PATH_DEV. 384 * Be *very* defensive. 385 */ 386 s = strdup(_PATH_DEV); 387 if (s != NULL) { 388 i = strlen(s); 389 if (i > 0 && s[i - 1] == '/') 390 s[i - 1] = '\0'; 391 iov[3].iov_base = s; 392 iov[3].iov_len = strlen(s) + 1; 393 } else { 394 iov[3].iov_base = _path_dev; 395 iov[3].iov_len = sizeof(_path_dev); 396 } 397 nmount(iov, 4, 0); 398 if (s != NULL) 399 free(s); 400 } 401 402 if (initial_transition != reroot_phase_two) { 403 /* 404 * Unmount reroot leftovers. This runs after init(8) 405 * gets reexecuted after reroot_phase_two() is done. 406 */ 407 error = unmount(_PATH_REROOT, MNT_FORCE); 408 if (error != 0 && errno != EINVAL) 409 warning("Cannot unmount %s: %m", _PATH_REROOT); 410 } 411 412 /* 413 * Start the state machine. 414 */ 415 transition(initial_transition); 416 417 /* 418 * Should never reach here. 419 */ 420 return 1; 421 } 422 423 /* 424 * Associate a function with a signal handler. 425 */ 426 static void 427 handle(sig_t handler, ...) 428 { 429 int sig; 430 struct sigaction sa; 431 sigset_t mask_everything; 432 va_list ap; 433 va_start(ap, handler); 434 435 sa.sa_handler = handler; 436 sigfillset(&mask_everything); 437 438 while ((sig = va_arg(ap, int)) != 0) { 439 sa.sa_mask = mask_everything; 440 /* XXX SA_RESTART? */ 441 sa.sa_flags = sig == SIGCHLD ? SA_NOCLDSTOP : 0; 442 sigaction(sig, &sa, NULL); 443 } 444 va_end(ap); 445 } 446 447 /* 448 * Delete a set of signals from a mask. 449 */ 450 static void 451 delset(sigset_t *maskp, ...) 452 { 453 int sig; 454 va_list ap; 455 va_start(ap, maskp); 456 457 while ((sig = va_arg(ap, int)) != 0) 458 sigdelset(maskp, sig); 459 va_end(ap); 460 } 461 462 /* 463 * Log a message and sleep for a while (to give someone an opportunity 464 * to read it and to save log or hardcopy output if the problem is chronic). 465 * NB: should send a message to the session logger to avoid blocking. 466 */ 467 static void 468 stall(const char *message, ...) 469 { 470 va_list ap; 471 va_start(ap, message); 472 473 vsyslog(LOG_ALERT, message, ap); 474 va_end(ap); 475 sleep(STALL_TIMEOUT); 476 } 477 478 /* 479 * Like stall(), but doesn't sleep. 480 * If cpp had variadic macros, the two functions could be #defines for another. 481 * NB: should send a message to the session logger to avoid blocking. 482 */ 483 static void 484 warning(const char *message, ...) 485 { 486 va_list ap; 487 va_start(ap, message); 488 489 vsyslog(LOG_ALERT, message, ap); 490 va_end(ap); 491 } 492 493 /* 494 * Log an emergency message. 495 * NB: should send a message to the session logger to avoid blocking. 496 */ 497 static void 498 emergency(const char *message, ...) 499 { 500 va_list ap; 501 va_start(ap, message); 502 503 vsyslog(LOG_EMERG, message, ap); 504 va_end(ap); 505 } 506 507 /* 508 * Catch an unexpected signal. 509 */ 510 static void 511 disaster(int sig) 512 { 513 514 emergency("fatal signal: %s", 515 (unsigned)sig < NSIG ? sys_siglist[sig] : "unknown signal"); 516 517 sleep(STALL_TIMEOUT); 518 _exit(sig); /* reboot */ 519 } 520 521 /* 522 * Get the security level of the kernel. 523 */ 524 static int 525 getsecuritylevel(void) 526 { 527 #ifdef KERN_SECURELVL 528 int name[2], curlevel; 529 size_t len; 530 531 name[0] = CTL_KERN; 532 name[1] = KERN_SECURELVL; 533 len = sizeof curlevel; 534 if (sysctl(name, 2, &curlevel, &len, NULL, 0) == -1) { 535 emergency("cannot get kernel security level: %m"); 536 return (-1); 537 } 538 return (curlevel); 539 #else 540 return (-1); 541 #endif 542 } 543 544 /* 545 * Set the security level of the kernel. 546 */ 547 static void 548 setsecuritylevel(int newlevel) 549 { 550 #ifdef KERN_SECURELVL 551 int name[2], curlevel; 552 553 curlevel = getsecuritylevel(); 554 if (newlevel == curlevel) 555 return; 556 name[0] = CTL_KERN; 557 name[1] = KERN_SECURELVL; 558 if (sysctl(name, 2, NULL, NULL, &newlevel, sizeof newlevel) == -1) { 559 emergency( 560 "cannot change kernel security level from %d to %d: %m", 561 curlevel, newlevel); 562 return; 563 } 564 #ifdef SECURE 565 warning("kernel security level changed from %d to %d", 566 curlevel, newlevel); 567 #endif 568 #endif 569 } 570 571 /* 572 * Change states in the finite state machine. 573 * The initial state is passed as an argument. 574 */ 575 static void 576 transition(state_t s) 577 { 578 579 current_state = s; 580 for (;;) 581 current_state = (state_t) (*current_state)(); 582 } 583 584 /* 585 * Start a session and allocate a controlling terminal. 586 * Only called by children of init after forking. 587 */ 588 static void 589 open_console(void) 590 { 591 int fd; 592 593 /* 594 * Try to open /dev/console. Open the device with O_NONBLOCK to 595 * prevent potential blocking on a carrier. 596 */ 597 revoke(_PATH_CONSOLE); 598 if ((fd = open(_PATH_CONSOLE, O_RDWR | O_NONBLOCK)) != -1) { 599 (void)fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) & ~O_NONBLOCK); 600 if (login_tty(fd) == 0) 601 return; 602 close(fd); 603 } 604 605 /* No luck. Log output to file if possible. */ 606 if ((fd = open(_PATH_DEVNULL, O_RDWR)) == -1) { 607 stall("cannot open null device."); 608 _exit(1); 609 } 610 if (fd != STDIN_FILENO) { 611 dup2(fd, STDIN_FILENO); 612 close(fd); 613 } 614 fd = open(_PATH_INITLOG, O_WRONLY | O_APPEND | O_CREAT, 0644); 615 if (fd == -1) 616 dup2(STDIN_FILENO, STDOUT_FILENO); 617 else if (fd != STDOUT_FILENO) { 618 dup2(fd, STDOUT_FILENO); 619 close(fd); 620 } 621 dup2(STDOUT_FILENO, STDERR_FILENO); 622 } 623 624 static const char * 625 get_shell(void) 626 { 627 static char kenv_value[PATH_MAX]; 628 629 if (kenv(KENV_GET, "init_shell", kenv_value, sizeof(kenv_value)) > 0) 630 return kenv_value; 631 else 632 return _PATH_BSHELL; 633 } 634 635 static void 636 write_stderr(const char *message) 637 { 638 639 write(STDERR_FILENO, message, strlen(message)); 640 } 641 642 static int 643 read_file(const char *path, void **bufp, size_t *bufsizep) 644 { 645 struct stat sb; 646 size_t bufsize; 647 void *buf; 648 ssize_t nbytes; 649 int error, fd; 650 651 fd = open(path, O_RDONLY); 652 if (fd < 0) { 653 emergency("%s: %m", path); 654 return (-1); 655 } 656 657 error = fstat(fd, &sb); 658 if (error != 0) { 659 emergency("fstat: %m"); 660 close(fd); 661 return (error); 662 } 663 664 bufsize = sb.st_size; 665 buf = malloc(bufsize); 666 if (buf == NULL) { 667 emergency("malloc: %m"); 668 close(fd); 669 return (error); 670 } 671 672 nbytes = read(fd, buf, bufsize); 673 if (nbytes != (ssize_t)bufsize) { 674 emergency("read: %m"); 675 close(fd); 676 free(buf); 677 return (error); 678 } 679 680 error = close(fd); 681 if (error != 0) { 682 emergency("close: %m"); 683 free(buf); 684 return (error); 685 } 686 687 *bufp = buf; 688 *bufsizep = bufsize; 689 690 return (0); 691 } 692 693 static int 694 create_file(const char *path, const void *buf, size_t bufsize) 695 { 696 ssize_t nbytes; 697 int error, fd; 698 699 fd = open(path, O_WRONLY | O_CREAT | O_EXCL, 0700); 700 if (fd < 0) { 701 emergency("%s: %m", path); 702 return (-1); 703 } 704 705 nbytes = write(fd, buf, bufsize); 706 if (nbytes != (ssize_t)bufsize) { 707 emergency("write: %m"); 708 close(fd); 709 return (-1); 710 } 711 712 error = close(fd); 713 if (error != 0) { 714 emergency("close: %m"); 715 return (-1); 716 } 717 718 return (0); 719 } 720 721 static int 722 mount_tmpfs(const char *fspath) 723 { 724 struct iovec *iov; 725 char errmsg[255]; 726 int error, iovlen; 727 728 iov = NULL; 729 iovlen = 0; 730 memset(errmsg, 0, sizeof(errmsg)); 731 build_iovec(&iov, &iovlen, "fstype", 732 __DECONST(void *, "tmpfs"), (size_t)-1); 733 build_iovec(&iov, &iovlen, "fspath", 734 __DECONST(void *, fspath), (size_t)-1); 735 build_iovec(&iov, &iovlen, "errmsg", 736 errmsg, sizeof(errmsg)); 737 738 error = nmount(iov, iovlen, 0); 739 if (error != 0) { 740 if (*errmsg != '\0') { 741 emergency("cannot mount tmpfs on %s: %s: %m", 742 fspath, errmsg); 743 } else { 744 emergency("cannot mount tmpfs on %s: %m", 745 fspath); 746 } 747 return (error); 748 } 749 return (0); 750 } 751 752 static state_func_t 753 reroot(void) 754 { 755 void *buf; 756 size_t bufsize; 757 int error; 758 759 buf = NULL; 760 bufsize = 0; 761 762 revoke_ttys(); 763 runshutdown(); 764 765 /* 766 * Make sure nobody can interfere with our scheme. 767 * Ignore ESRCH, which can apparently happen when 768 * there are no processes to kill. 769 */ 770 error = kill(-1, SIGKILL); 771 if (error != 0 && errno != ESRCH) { 772 emergency("kill(2) failed: %m"); 773 goto out; 774 } 775 776 /* 777 * Copy the init binary into tmpfs, so that we can unmount 778 * the old rootfs without committing suicide. 779 */ 780 error = read_file(init_path_argv0, &buf, &bufsize); 781 if (error != 0) 782 goto out; 783 error = mount_tmpfs(_PATH_REROOT); 784 if (error != 0) 785 goto out; 786 error = create_file(_PATH_REROOT_INIT, buf, bufsize); 787 if (error != 0) 788 goto out; 789 790 /* 791 * Execute the temporary init. 792 */ 793 execl(_PATH_REROOT_INIT, _PATH_REROOT_INIT, "-r", NULL); 794 emergency("cannot exec %s: %m", _PATH_REROOT_INIT); 795 796 out: 797 emergency("reroot failed; going to single user mode"); 798 free(buf); 799 return (state_func_t) single_user; 800 } 801 802 static state_func_t 803 reroot_phase_two(void) 804 { 805 char init_path[PATH_MAX], *path, *path_component; 806 size_t init_path_len; 807 int nbytes, error; 808 809 /* 810 * Ask the kernel to mount the new rootfs. 811 */ 812 error = reboot(RB_REROOT); 813 if (error != 0) { 814 emergency("RB_REBOOT failed: %m"); 815 goto out; 816 } 817 818 /* 819 * Figure out where the destination init(8) binary is. Note that 820 * the path could be different than what we've started with. Use 821 * the value from kenv, if set, or the one from sysctl otherwise. 822 * The latter defaults to a hardcoded value, but can be overridden 823 * by a build time option. 824 */ 825 nbytes = kenv(KENV_GET, "init_path", init_path, sizeof(init_path)); 826 if (nbytes <= 0) { 827 init_path_len = sizeof(init_path); 828 error = sysctlbyname("kern.init_path", 829 init_path, &init_path_len, NULL, 0); 830 if (error != 0) { 831 emergency("failed to retrieve kern.init_path: %m"); 832 goto out; 833 } 834 } 835 836 /* 837 * Repeat the init search logic from sys/kern/init_path.c 838 */ 839 path_component = init_path; 840 while ((path = strsep(&path_component, ":")) != NULL) { 841 /* 842 * Execute init(8) from the new rootfs. 843 */ 844 execl(path, path, NULL); 845 } 846 emergency("cannot exec init from %s: %m", init_path); 847 848 out: 849 emergency("reroot failed; going to single user mode"); 850 return (state_func_t) single_user; 851 } 852 853 /* 854 * Bring the system up single user. 855 */ 856 static state_func_t 857 single_user(void) 858 { 859 pid_t pid, wpid; 860 int status; 861 sigset_t mask; 862 const char *shell; 863 char *argv[2]; 864 struct timeval tv, tn; 865 #ifdef SECURE 866 struct ttyent *typ; 867 struct passwd *pp; 868 static const char banner[] = 869 "Enter root password, or ^D to go multi-user\n"; 870 char *clear, *password; 871 #endif 872 #ifdef DEBUGSHELL 873 char altshell[128]; 874 #endif 875 876 if (Reboot) { 877 /* Instead of going single user, let's reboot the machine */ 878 sync(); 879 if (reboot(howto) == -1) { 880 emergency("reboot(%#x) failed, %m", howto); 881 _exit(1); /* panic and reboot */ 882 } 883 warning("reboot(%#x) returned", howto); 884 _exit(0); /* panic as well */ 885 } 886 887 shell = get_shell(); 888 889 if ((pid = fork()) == 0) { 890 /* 891 * Start the single user session. 892 */ 893 open_console(); 894 895 #ifdef SECURE 896 /* 897 * Check the root password. 898 * We don't care if the console is 'on' by default; 899 * it's the only tty that can be 'off' and 'secure'. 900 */ 901 typ = getttynam("console"); 902 pp = getpwnam("root"); 903 if (typ && (typ->ty_status & TTY_SECURE) == 0 && 904 pp && *pp->pw_passwd) { 905 write_stderr(banner); 906 for (;;) { 907 clear = getpass("Password:"); 908 if (clear == NULL || *clear == '\0') 909 _exit(0); 910 password = crypt(clear, pp->pw_passwd); 911 explicit_bzero(clear, _PASSWORD_LEN); 912 if (password != NULL && 913 strcmp(password, pp->pw_passwd) == 0) 914 break; 915 warning("single-user login failed\n"); 916 } 917 } 918 endttyent(); 919 endpwent(); 920 #endif /* SECURE */ 921 922 #ifdef DEBUGSHELL 923 { 924 char *cp = altshell; 925 int num; 926 927 #define SHREQUEST "Enter full pathname of shell or RETURN for " 928 write_stderr(SHREQUEST); 929 write_stderr(shell); 930 write_stderr(": "); 931 while ((num = read(STDIN_FILENO, cp, 1)) != -1 && 932 num != 0 && *cp != '\n' && cp < &altshell[127]) 933 cp++; 934 *cp = '\0'; 935 if (altshell[0] != '\0') 936 shell = altshell; 937 } 938 #endif /* DEBUGSHELL */ 939 940 /* 941 * Unblock signals. 942 * We catch all the interesting ones, 943 * and those are reset to SIG_DFL on exec. 944 */ 945 sigemptyset(&mask); 946 sigprocmask(SIG_SETMASK, &mask, NULL); 947 948 /* 949 * Fire off a shell. 950 * If the default one doesn't work, try the Bourne shell. 951 */ 952 953 char name[] = "-sh"; 954 955 argv[0] = name; 956 argv[1] = NULL; 957 execv(shell, argv); 958 emergency("can't exec %s for single user: %m", shell); 959 execv(_PATH_BSHELL, argv); 960 emergency("can't exec %s for single user: %m", _PATH_BSHELL); 961 sleep(STALL_TIMEOUT); 962 _exit(1); 963 } 964 965 if (pid == -1) { 966 /* 967 * We are seriously hosed. Do our best. 968 */ 969 emergency("can't fork single-user shell, trying again"); 970 while (waitpid(-1, (int *) 0, WNOHANG) > 0) 971 continue; 972 return (state_func_t) single_user; 973 } 974 975 requested_transition = 0; 976 do { 977 if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1) 978 collect_child(wpid); 979 if (wpid == -1) { 980 if (errno == EINTR) 981 continue; 982 warning("wait for single-user shell failed: %m; restarting"); 983 return (state_func_t) single_user; 984 } 985 if (wpid == pid && WIFSTOPPED(status)) { 986 warning("init: shell stopped, restarting\n"); 987 kill(pid, SIGCONT); 988 wpid = -1; 989 } 990 } while (wpid != pid && !requested_transition); 991 992 if (requested_transition) 993 return (state_func_t) requested_transition; 994 995 if (!WIFEXITED(status)) { 996 if (WTERMSIG(status) == SIGKILL) { 997 /* 998 * reboot(8) killed shell? 999 */ 1000 warning("single user shell terminated."); 1001 gettimeofday(&tv, NULL); 1002 tn = tv; 1003 tv.tv_sec += STALL_TIMEOUT; 1004 while (tv.tv_sec > tn.tv_sec || (tv.tv_sec == 1005 tn.tv_sec && tv.tv_usec > tn.tv_usec)) { 1006 sleep(1); 1007 gettimeofday(&tn, NULL); 1008 } 1009 _exit(0); 1010 } else { 1011 warning("single user shell terminated, restarting"); 1012 return (state_func_t) single_user; 1013 } 1014 } 1015 1016 runcom_mode = FASTBOOT; 1017 return (state_func_t) runcom; 1018 } 1019 1020 /* 1021 * Run the system startup script. 1022 */ 1023 static state_func_t 1024 runcom(void) 1025 { 1026 state_func_t next_transition; 1027 1028 if ((next_transition = run_script(_PATH_RUNCOM)) != NULL) 1029 return next_transition; 1030 1031 runcom_mode = AUTOBOOT; /* the default */ 1032 return (state_func_t) read_ttys; 1033 } 1034 1035 static void 1036 execute_script(char *argv[]) 1037 { 1038 struct sigaction sa; 1039 const char *shell, *script; 1040 int error; 1041 1042 bzero(&sa, sizeof(sa)); 1043 sigemptyset(&sa.sa_mask); 1044 sa.sa_handler = SIG_IGN; 1045 sigaction(SIGTSTP, &sa, NULL); 1046 sigaction(SIGHUP, &sa, NULL); 1047 1048 open_console(); 1049 1050 sigprocmask(SIG_SETMASK, &sa.sa_mask, NULL); 1051 #ifdef LOGIN_CAP 1052 setprocresources(RESOURCE_RC); 1053 #endif 1054 1055 /* 1056 * Try to directly execute the script first. If it 1057 * fails, try the old method of passing the script path 1058 * to sh(1). Don't complain if it fails because of 1059 * the missing execute bit. 1060 */ 1061 script = argv[1]; 1062 error = access(script, X_OK); 1063 if (error == 0) { 1064 execv(script, argv + 1); 1065 warning("can't directly exec %s: %m", script); 1066 } else if (errno != EACCES) { 1067 warning("can't access %s: %m", script); 1068 } 1069 1070 shell = get_shell(); 1071 execv(shell, argv); 1072 stall("can't exec %s for %s: %m", shell, script); 1073 } 1074 1075 /* 1076 * Execute binary, replacing init(8) as PID 1. 1077 */ 1078 static void 1079 replace_init(char *path) 1080 { 1081 char *argv[3]; 1082 char sh[] = "sh"; 1083 1084 argv[0] = sh; 1085 argv[1] = path; 1086 argv[2] = NULL; 1087 1088 execute_script(argv); 1089 } 1090 1091 /* 1092 * Run a shell script. 1093 * Returns 0 on success, otherwise the next transition to enter: 1094 * - single_user if fork/execv/waitpid failed, or if the script 1095 * terminated with a signal or exit code != 0. 1096 * - death_single if a SIGTERM was delivered to init(8). 1097 */ 1098 static state_func_t 1099 run_script(const char *script) 1100 { 1101 pid_t pid, wpid; 1102 int status; 1103 char *argv[4]; 1104 const char *shell; 1105 1106 shell = get_shell(); 1107 1108 if ((pid = fork()) == 0) { 1109 1110 char _sh[] = "sh"; 1111 char _autoboot[] = "autoboot"; 1112 1113 argv[0] = _sh; 1114 argv[1] = __DECONST(char *, script); 1115 argv[2] = runcom_mode == AUTOBOOT ? _autoboot : 0; 1116 argv[3] = NULL; 1117 1118 execute_script(argv); 1119 sleep(STALL_TIMEOUT); 1120 _exit(1); /* force single user mode */ 1121 } 1122 1123 if (pid == -1) { 1124 emergency("can't fork for %s on %s: %m", shell, script); 1125 while (waitpid(-1, (int *) 0, WNOHANG) > 0) 1126 continue; 1127 sleep(STALL_TIMEOUT); 1128 return (state_func_t) single_user; 1129 } 1130 1131 /* 1132 * Copied from single_user(). This is a bit paranoid. 1133 */ 1134 requested_transition = 0; 1135 do { 1136 if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1) 1137 collect_child(wpid); 1138 if (wpid == -1) { 1139 if (requested_transition == death_single || 1140 requested_transition == reroot) 1141 return (state_func_t) requested_transition; 1142 if (errno == EINTR) 1143 continue; 1144 warning("wait for %s on %s failed: %m; going to " 1145 "single user mode", shell, script); 1146 return (state_func_t) single_user; 1147 } 1148 if (wpid == pid && WIFSTOPPED(status)) { 1149 warning("init: %s on %s stopped, restarting\n", 1150 shell, script); 1151 kill(pid, SIGCONT); 1152 wpid = -1; 1153 } 1154 } while (wpid != pid); 1155 1156 if (WIFSIGNALED(status) && WTERMSIG(status) == SIGTERM && 1157 requested_transition == catatonia) { 1158 /* /etc/rc executed /sbin/reboot; wait for the end quietly */ 1159 sigset_t s; 1160 1161 sigfillset(&s); 1162 for (;;) 1163 sigsuspend(&s); 1164 } 1165 1166 if (!WIFEXITED(status)) { 1167 warning("%s on %s terminated abnormally, going to single " 1168 "user mode", shell, script); 1169 return (state_func_t) single_user; 1170 } 1171 1172 if (WEXITSTATUS(status)) 1173 return (state_func_t) single_user; 1174 1175 return (state_func_t) 0; 1176 } 1177 1178 /* 1179 * Open the session database. 1180 * 1181 * NB: We could pass in the size here; is it necessary? 1182 */ 1183 static int 1184 start_session_db(void) 1185 { 1186 if (session_db && (*session_db->close)(session_db)) 1187 emergency("session database close: %m"); 1188 if ((session_db = dbopen(NULL, O_RDWR, 0, DB_HASH, NULL)) == NULL) { 1189 emergency("session database open: %m"); 1190 return (1); 1191 } 1192 return (0); 1193 1194 } 1195 1196 /* 1197 * Add a new login session. 1198 */ 1199 static void 1200 add_session(session_t *sp) 1201 { 1202 DBT key; 1203 DBT data; 1204 1205 key.data = &sp->se_process; 1206 key.size = sizeof sp->se_process; 1207 data.data = &sp; 1208 data.size = sizeof sp; 1209 1210 if ((*session_db->put)(session_db, &key, &data, 0)) 1211 emergency("insert %d: %m", sp->se_process); 1212 } 1213 1214 /* 1215 * Delete an old login session. 1216 */ 1217 static void 1218 del_session(session_t *sp) 1219 { 1220 DBT key; 1221 1222 key.data = &sp->se_process; 1223 key.size = sizeof sp->se_process; 1224 1225 if ((*session_db->del)(session_db, &key, 0)) 1226 emergency("delete %d: %m", sp->se_process); 1227 } 1228 1229 /* 1230 * Look up a login session by pid. 1231 */ 1232 static session_t * 1233 find_session(pid_t pid) 1234 { 1235 DBT key; 1236 DBT data; 1237 session_t *ret; 1238 1239 key.data = &pid; 1240 key.size = sizeof pid; 1241 if ((*session_db->get)(session_db, &key, &data, 0) != 0) 1242 return 0; 1243 bcopy(data.data, (char *)&ret, sizeof(ret)); 1244 return ret; 1245 } 1246 1247 /* 1248 * Construct an argument vector from a command line. 1249 */ 1250 static char ** 1251 construct_argv(char *command) 1252 { 1253 int argc = 0; 1254 char **argv = (char **) malloc(((strlen(command) + 1) / 2 + 1) 1255 * sizeof (char *)); 1256 1257 if ((argv[argc++] = strk(command)) == NULL) { 1258 free(argv); 1259 return (NULL); 1260 } 1261 while ((argv[argc++] = strk((char *) 0)) != NULL) 1262 continue; 1263 return argv; 1264 } 1265 1266 /* 1267 * Deallocate a session descriptor. 1268 */ 1269 static void 1270 free_session(session_t *sp) 1271 { 1272 free(sp->se_device); 1273 if (sp->se_getty) { 1274 free(sp->se_getty); 1275 free(sp->se_getty_argv_space); 1276 free(sp->se_getty_argv); 1277 } 1278 if (sp->se_window) { 1279 free(sp->se_window); 1280 free(sp->se_window_argv_space); 1281 free(sp->se_window_argv); 1282 } 1283 if (sp->se_type) 1284 free(sp->se_type); 1285 free(sp); 1286 } 1287 1288 /* 1289 * Allocate a new session descriptor. 1290 * Mark it SE_PRESENT. 1291 */ 1292 static session_t * 1293 new_session(session_t *sprev, struct ttyent *typ) 1294 { 1295 session_t *sp; 1296 1297 if ((typ->ty_status & TTY_ON) == 0 || 1298 typ->ty_name == 0 || 1299 typ->ty_getty == 0) 1300 return 0; 1301 1302 sp = (session_t *) calloc(1, sizeof (session_t)); 1303 1304 sp->se_flags |= SE_PRESENT; 1305 1306 if ((typ->ty_status & TTY_IFEXISTS) != 0) 1307 sp->se_flags |= SE_IFEXISTS; 1308 1309 if ((typ->ty_status & TTY_IFCONSOLE) != 0) 1310 sp->se_flags |= SE_IFCONSOLE; 1311 1312 if (asprintf(&sp->se_device, "%s%s", _PATH_DEV, typ->ty_name) < 0) 1313 err(1, "asprintf"); 1314 1315 if (setupargv(sp, typ) == 0) { 1316 free_session(sp); 1317 return (0); 1318 } 1319 1320 sp->se_next = 0; 1321 if (sprev == NULL) { 1322 sessions = sp; 1323 sp->se_prev = 0; 1324 } else { 1325 sprev->se_next = sp; 1326 sp->se_prev = sprev; 1327 } 1328 1329 return sp; 1330 } 1331 1332 /* 1333 * Calculate getty and if useful window argv vectors. 1334 */ 1335 static int 1336 setupargv(session_t *sp, struct ttyent *typ) 1337 { 1338 1339 if (sp->se_getty) { 1340 free(sp->se_getty); 1341 free(sp->se_getty_argv_space); 1342 free(sp->se_getty_argv); 1343 } 1344 if (asprintf(&sp->se_getty, "%s %s", typ->ty_getty, typ->ty_name) < 0) 1345 err(1, "asprintf"); 1346 sp->se_getty_argv_space = strdup(sp->se_getty); 1347 sp->se_getty_argv = construct_argv(sp->se_getty_argv_space); 1348 if (sp->se_getty_argv == NULL) { 1349 warning("can't parse getty for port %s", sp->se_device); 1350 free(sp->se_getty); 1351 free(sp->se_getty_argv_space); 1352 sp->se_getty = sp->se_getty_argv_space = 0; 1353 return (0); 1354 } 1355 if (sp->se_window) { 1356 free(sp->se_window); 1357 free(sp->se_window_argv_space); 1358 free(sp->se_window_argv); 1359 } 1360 sp->se_window = sp->se_window_argv_space = 0; 1361 sp->se_window_argv = 0; 1362 if (typ->ty_window) { 1363 sp->se_window = strdup(typ->ty_window); 1364 sp->se_window_argv_space = strdup(sp->se_window); 1365 sp->se_window_argv = construct_argv(sp->se_window_argv_space); 1366 if (sp->se_window_argv == NULL) { 1367 warning("can't parse window for port %s", 1368 sp->se_device); 1369 free(sp->se_window_argv_space); 1370 free(sp->se_window); 1371 sp->se_window = sp->se_window_argv_space = 0; 1372 return (0); 1373 } 1374 } 1375 if (sp->se_type) 1376 free(sp->se_type); 1377 sp->se_type = typ->ty_type ? strdup(typ->ty_type) : 0; 1378 return (1); 1379 } 1380 1381 /* 1382 * Walk the list of ttys and create sessions for each active line. 1383 */ 1384 static state_func_t 1385 read_ttys(void) 1386 { 1387 session_t *sp, *snext; 1388 struct ttyent *typ; 1389 1390 /* 1391 * Destroy any previous session state. 1392 * There shouldn't be any, but just in case... 1393 */ 1394 for (sp = sessions; sp; sp = snext) { 1395 snext = sp->se_next; 1396 free_session(sp); 1397 } 1398 sessions = 0; 1399 if (start_session_db()) 1400 return (state_func_t) single_user; 1401 1402 /* 1403 * Allocate a session entry for each active port. 1404 * Note that sp starts at 0. 1405 */ 1406 while ((typ = getttyent()) != NULL) 1407 if ((snext = new_session(sp, typ)) != NULL) 1408 sp = snext; 1409 1410 endttyent(); 1411 1412 return (state_func_t) multi_user; 1413 } 1414 1415 /* 1416 * Start a window system running. 1417 */ 1418 static void 1419 start_window_system(session_t *sp) 1420 { 1421 pid_t pid; 1422 sigset_t mask; 1423 char term[64], *env[2]; 1424 int status; 1425 1426 if ((pid = fork()) == -1) { 1427 emergency("can't fork for window system on port %s: %m", 1428 sp->se_device); 1429 /* hope that getty fails and we can try again */ 1430 return; 1431 } 1432 if (pid) { 1433 waitpid(-1, &status, 0); 1434 return; 1435 } 1436 1437 /* reparent window process to the init to not make a zombie on exit */ 1438 if ((pid = fork()) == -1) { 1439 emergency("can't fork for window system on port %s: %m", 1440 sp->se_device); 1441 _exit(1); 1442 } 1443 if (pid) 1444 _exit(0); 1445 1446 sigemptyset(&mask); 1447 sigprocmask(SIG_SETMASK, &mask, NULL); 1448 1449 if (setsid() < 0) 1450 emergency("setsid failed (window) %m"); 1451 1452 #ifdef LOGIN_CAP 1453 setprocresources(RESOURCE_WINDOW); 1454 #endif 1455 if (sp->se_type) { 1456 /* Don't use malloc after fork */ 1457 strcpy(term, "TERM="); 1458 strlcat(term, sp->se_type, sizeof(term)); 1459 env[0] = term; 1460 env[1] = NULL; 1461 } 1462 else 1463 env[0] = NULL; 1464 execve(sp->se_window_argv[0], sp->se_window_argv, env); 1465 stall("can't exec window system '%s' for port %s: %m", 1466 sp->se_window_argv[0], sp->se_device); 1467 _exit(1); 1468 } 1469 1470 /* 1471 * Start a login session running. 1472 */ 1473 static pid_t 1474 start_getty(session_t *sp) 1475 { 1476 pid_t pid; 1477 sigset_t mask; 1478 time_t current_time = time((time_t *) 0); 1479 int too_quick = 0; 1480 char term[64], *env[2]; 1481 1482 if (current_time >= sp->se_started && 1483 current_time - sp->se_started < GETTY_SPACING) { 1484 if (++sp->se_nspace > GETTY_NSPACE) { 1485 sp->se_nspace = 0; 1486 too_quick = 1; 1487 } 1488 } else 1489 sp->se_nspace = 0; 1490 1491 /* 1492 * fork(), not vfork() -- we can't afford to block. 1493 */ 1494 if ((pid = fork()) == -1) { 1495 emergency("can't fork for getty on port %s: %m", sp->se_device); 1496 return -1; 1497 } 1498 1499 if (pid) 1500 return pid; 1501 1502 if (too_quick) { 1503 warning("getty repeating too quickly on port %s, sleeping %d secs", 1504 sp->se_device, GETTY_SLEEP); 1505 sleep((unsigned) GETTY_SLEEP); 1506 } 1507 1508 if (sp->se_window) { 1509 start_window_system(sp); 1510 sleep(WINDOW_WAIT); 1511 } 1512 1513 sigemptyset(&mask); 1514 sigprocmask(SIG_SETMASK, &mask, NULL); 1515 1516 #ifdef LOGIN_CAP 1517 setprocresources(RESOURCE_GETTY); 1518 #endif 1519 if (sp->se_type) { 1520 /* Don't use malloc after fork */ 1521 strcpy(term, "TERM="); 1522 strlcat(term, sp->se_type, sizeof(term)); 1523 env[0] = term; 1524 env[1] = NULL; 1525 } else 1526 env[0] = NULL; 1527 execve(sp->se_getty_argv[0], sp->se_getty_argv, env); 1528 stall("can't exec getty '%s' for port %s: %m", 1529 sp->se_getty_argv[0], sp->se_device); 1530 _exit(1); 1531 } 1532 1533 /* 1534 * Return 1 if the session is defined as "onifexists" 1535 * or "onifconsole" and the device node does not exist. 1536 */ 1537 static int 1538 session_has_no_tty(session_t *sp) 1539 { 1540 int fd; 1541 1542 if ((sp->se_flags & SE_IFEXISTS) == 0 && 1543 (sp->se_flags & SE_IFCONSOLE) == 0) 1544 return (0); 1545 1546 fd = open(sp->se_device, O_RDONLY | O_NONBLOCK, 0); 1547 if (fd < 0) { 1548 if (errno == ENOENT) 1549 return (1); 1550 return (0); 1551 } 1552 1553 close(fd); 1554 return (0); 1555 } 1556 1557 /* 1558 * Collect exit status for a child. 1559 * If an exiting login, start a new login running. 1560 */ 1561 static void 1562 collect_child(pid_t pid) 1563 { 1564 session_t *sp, *sprev, *snext; 1565 1566 if (! sessions) 1567 return; 1568 1569 if (! (sp = find_session(pid))) 1570 return; 1571 1572 del_session(sp); 1573 sp->se_process = 0; 1574 1575 if (sp->se_flags & SE_SHUTDOWN || 1576 session_has_no_tty(sp)) { 1577 if ((sprev = sp->se_prev) != NULL) 1578 sprev->se_next = sp->se_next; 1579 else 1580 sessions = sp->se_next; 1581 if ((snext = sp->se_next) != NULL) 1582 snext->se_prev = sp->se_prev; 1583 free_session(sp); 1584 return; 1585 } 1586 1587 if ((pid = start_getty(sp)) == -1) { 1588 /* serious trouble */ 1589 requested_transition = clean_ttys; 1590 return; 1591 } 1592 1593 sp->se_process = pid; 1594 sp->se_started = time((time_t *) 0); 1595 add_session(sp); 1596 } 1597 1598 /* 1599 * Catch a signal and request a state transition. 1600 */ 1601 static void 1602 transition_handler(int sig) 1603 { 1604 1605 switch (sig) { 1606 case SIGHUP: 1607 if (current_state == read_ttys || current_state == multi_user || 1608 current_state == clean_ttys || current_state == catatonia) 1609 requested_transition = clean_ttys; 1610 break; 1611 case SIGUSR2: 1612 howto = RB_POWEROFF; 1613 case SIGUSR1: 1614 howto |= RB_HALT; 1615 case SIGWINCH: 1616 case SIGINT: 1617 if (sig == SIGWINCH) 1618 howto |= RB_POWERCYCLE; 1619 Reboot = TRUE; 1620 case SIGTERM: 1621 if (current_state == read_ttys || current_state == multi_user || 1622 current_state == clean_ttys || current_state == catatonia) 1623 requested_transition = death; 1624 else 1625 requested_transition = death_single; 1626 break; 1627 case SIGTSTP: 1628 if (current_state == runcom || current_state == read_ttys || 1629 current_state == clean_ttys || 1630 current_state == multi_user || current_state == catatonia) 1631 requested_transition = catatonia; 1632 break; 1633 case SIGEMT: 1634 requested_transition = reroot; 1635 break; 1636 default: 1637 requested_transition = 0; 1638 break; 1639 } 1640 } 1641 1642 /* 1643 * Take the system multiuser. 1644 */ 1645 static state_func_t 1646 multi_user(void) 1647 { 1648 pid_t pid; 1649 session_t *sp; 1650 1651 requested_transition = 0; 1652 1653 /* 1654 * If the administrator has not set the security level to -1 1655 * to indicate that the kernel should not run multiuser in secure 1656 * mode, and the run script has not set a higher level of security 1657 * than level 1, then put the kernel into secure mode. 1658 */ 1659 if (getsecuritylevel() == 0) 1660 setsecuritylevel(1); 1661 1662 for (sp = sessions; sp; sp = sp->se_next) { 1663 if (sp->se_process) 1664 continue; 1665 if (session_has_no_tty(sp)) 1666 continue; 1667 if ((pid = start_getty(sp)) == -1) { 1668 /* serious trouble */ 1669 requested_transition = clean_ttys; 1670 break; 1671 } 1672 sp->se_process = pid; 1673 sp->se_started = time((time_t *) 0); 1674 add_session(sp); 1675 } 1676 1677 while (!requested_transition) 1678 if ((pid = waitpid(-1, (int *) 0, 0)) != -1) 1679 collect_child(pid); 1680 1681 return (state_func_t) requested_transition; 1682 } 1683 1684 /* 1685 * This is an (n*2)+(n^2) algorithm. We hope it isn't run often... 1686 */ 1687 static state_func_t 1688 clean_ttys(void) 1689 { 1690 session_t *sp, *sprev; 1691 struct ttyent *typ; 1692 int devlen; 1693 char *old_getty, *old_window, *old_type; 1694 1695 /* 1696 * mark all sessions for death, (!SE_PRESENT) 1697 * as we find or create new ones they'll be marked as keepers, 1698 * we'll later nuke all the ones not found in /etc/ttys 1699 */ 1700 for (sp = sessions; sp != NULL; sp = sp->se_next) 1701 sp->se_flags &= ~SE_PRESENT; 1702 1703 devlen = sizeof(_PATH_DEV) - 1; 1704 while ((typ = getttyent()) != NULL) { 1705 for (sprev = 0, sp = sessions; sp; sprev = sp, sp = sp->se_next) 1706 if (strcmp(typ->ty_name, sp->se_device + devlen) == 0) 1707 break; 1708 1709 if (sp) { 1710 /* we want this one to live */ 1711 sp->se_flags |= SE_PRESENT; 1712 if ((typ->ty_status & TTY_ON) == 0 || 1713 typ->ty_getty == 0) { 1714 sp->se_flags |= SE_SHUTDOWN; 1715 kill(sp->se_process, SIGHUP); 1716 continue; 1717 } 1718 sp->se_flags &= ~SE_SHUTDOWN; 1719 old_getty = sp->se_getty ? strdup(sp->se_getty) : 0; 1720 old_window = sp->se_window ? strdup(sp->se_window) : 0; 1721 old_type = sp->se_type ? strdup(sp->se_type) : 0; 1722 if (setupargv(sp, typ) == 0) { 1723 warning("can't parse getty for port %s", 1724 sp->se_device); 1725 sp->se_flags |= SE_SHUTDOWN; 1726 kill(sp->se_process, SIGHUP); 1727 } 1728 else if ( !old_getty 1729 || (!old_type && sp->se_type) 1730 || (old_type && !sp->se_type) 1731 || (!old_window && sp->se_window) 1732 || (old_window && !sp->se_window) 1733 || (strcmp(old_getty, sp->se_getty) != 0) 1734 || (old_window && strcmp(old_window, sp->se_window) != 0) 1735 || (old_type && strcmp(old_type, sp->se_type) != 0) 1736 ) { 1737 /* Don't set SE_SHUTDOWN here */ 1738 sp->se_nspace = 0; 1739 sp->se_started = 0; 1740 kill(sp->se_process, SIGHUP); 1741 } 1742 if (old_getty) 1743 free(old_getty); 1744 if (old_window) 1745 free(old_window); 1746 if (old_type) 1747 free(old_type); 1748 continue; 1749 } 1750 1751 new_session(sprev, typ); 1752 } 1753 1754 endttyent(); 1755 1756 /* 1757 * sweep through and kill all deleted sessions 1758 * ones who's /etc/ttys line was deleted (SE_PRESENT unset) 1759 */ 1760 for (sp = sessions; sp != NULL; sp = sp->se_next) { 1761 if ((sp->se_flags & SE_PRESENT) == 0) { 1762 sp->se_flags |= SE_SHUTDOWN; 1763 kill(sp->se_process, SIGHUP); 1764 } 1765 } 1766 1767 return (state_func_t) multi_user; 1768 } 1769 1770 /* 1771 * Block further logins. 1772 */ 1773 static state_func_t 1774 catatonia(void) 1775 { 1776 session_t *sp; 1777 1778 for (sp = sessions; sp; sp = sp->se_next) 1779 sp->se_flags |= SE_SHUTDOWN; 1780 1781 return (state_func_t) multi_user; 1782 } 1783 1784 /* 1785 * Note SIGALRM. 1786 */ 1787 static void 1788 alrm_handler(int sig) 1789 { 1790 1791 (void)sig; 1792 clang = 1; 1793 } 1794 1795 /* 1796 * Bring the system down to single user. 1797 */ 1798 static state_func_t 1799 death(void) 1800 { 1801 int block, blocked; 1802 size_t len; 1803 1804 /* Temporarily block suspend. */ 1805 len = sizeof(blocked); 1806 block = 1; 1807 if (sysctlbyname("kern.suspend_blocked", &blocked, &len, 1808 &block, sizeof(block)) == -1) 1809 blocked = 0; 1810 1811 /* 1812 * Also revoke the TTY here. Because runshutdown() may reopen 1813 * the TTY whose getty we're killing here, there is no guarantee 1814 * runshutdown() will perform the initial open() call, causing 1815 * the terminal attributes to be misconfigured. 1816 */ 1817 revoke_ttys(); 1818 1819 /* Try to run the rc.shutdown script within a period of time */ 1820 runshutdown(); 1821 1822 /* Unblock suspend if we blocked it. */ 1823 if (!blocked) 1824 sysctlbyname("kern.suspend_blocked", NULL, NULL, 1825 &blocked, sizeof(blocked)); 1826 1827 return (state_func_t) death_single; 1828 } 1829 1830 /* 1831 * Do what is necessary to reinitialize single user mode or reboot 1832 * from an incomplete state. 1833 */ 1834 static state_func_t 1835 death_single(void) 1836 { 1837 int i; 1838 pid_t pid; 1839 static const int death_sigs[2] = { SIGTERM, SIGKILL }; 1840 1841 revoke(_PATH_CONSOLE); 1842 1843 for (i = 0; i < 2; ++i) { 1844 if (kill(-1, death_sigs[i]) == -1 && errno == ESRCH) 1845 return (state_func_t) single_user; 1846 1847 clang = 0; 1848 alarm(DEATH_WATCH); 1849 do 1850 if ((pid = waitpid(-1, (int *)0, 0)) != -1) 1851 collect_child(pid); 1852 while (clang == 0 && errno != ECHILD); 1853 1854 if (errno == ECHILD) 1855 return (state_func_t) single_user; 1856 } 1857 1858 warning("some processes would not die; ps axl advised"); 1859 1860 return (state_func_t) single_user; 1861 } 1862 1863 static void 1864 revoke_ttys(void) 1865 { 1866 session_t *sp; 1867 1868 for (sp = sessions; sp; sp = sp->se_next) { 1869 sp->se_flags |= SE_SHUTDOWN; 1870 kill(sp->se_process, SIGHUP); 1871 revoke(sp->se_device); 1872 } 1873 } 1874 1875 /* 1876 * Run the system shutdown script. 1877 * 1878 * Exit codes: XXX I should document more 1879 * -2 shutdown script terminated abnormally 1880 * -1 fatal error - can't run script 1881 * 0 good. 1882 * >0 some error (exit code) 1883 */ 1884 static int 1885 runshutdown(void) 1886 { 1887 pid_t pid, wpid; 1888 int status; 1889 int shutdowntimeout; 1890 size_t len; 1891 char *argv[4]; 1892 struct stat sb; 1893 1894 /* 1895 * rc.shutdown is optional, so to prevent any unnecessary 1896 * complaints from the shell we simply don't run it if the 1897 * file does not exist. If the stat() here fails for other 1898 * reasons, we'll let the shell complain. 1899 */ 1900 if (stat(_PATH_RUNDOWN, &sb) == -1 && errno == ENOENT) 1901 return 0; 1902 1903 if ((pid = fork()) == 0) { 1904 char _sh[] = "sh"; 1905 char _reboot[] = "reboot"; 1906 char _single[] = "single"; 1907 char _path_rundown[] = _PATH_RUNDOWN; 1908 1909 argv[0] = _sh; 1910 argv[1] = _path_rundown; 1911 argv[2] = Reboot ? _reboot : _single; 1912 argv[3] = NULL; 1913 1914 execute_script(argv); 1915 _exit(1); /* force single user mode */ 1916 } 1917 1918 if (pid == -1) { 1919 emergency("can't fork for %s: %m", _PATH_RUNDOWN); 1920 while (waitpid(-1, (int *) 0, WNOHANG) > 0) 1921 continue; 1922 sleep(STALL_TIMEOUT); 1923 return -1; 1924 } 1925 1926 len = sizeof(shutdowntimeout); 1927 if (sysctlbyname("kern.init_shutdown_timeout", &shutdowntimeout, &len, 1928 NULL, 0) == -1 || shutdowntimeout < 2) 1929 shutdowntimeout = DEATH_SCRIPT; 1930 alarm(shutdowntimeout); 1931 clang = 0; 1932 /* 1933 * Copied from single_user(). This is a bit paranoid. 1934 * Use the same ALRM handler. 1935 */ 1936 do { 1937 if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1) 1938 collect_child(wpid); 1939 if (clang == 1) { 1940 /* we were waiting for the sub-shell */ 1941 kill(wpid, SIGTERM); 1942 warning("timeout expired for %s: %m; going to " 1943 "single user mode", _PATH_RUNDOWN); 1944 return -1; 1945 } 1946 if (wpid == -1) { 1947 if (errno == EINTR) 1948 continue; 1949 warning("wait for %s failed: %m; going to " 1950 "single user mode", _PATH_RUNDOWN); 1951 return -1; 1952 } 1953 if (wpid == pid && WIFSTOPPED(status)) { 1954 warning("init: %s stopped, restarting\n", 1955 _PATH_RUNDOWN); 1956 kill(pid, SIGCONT); 1957 wpid = -1; 1958 } 1959 } while (wpid != pid && !clang); 1960 1961 /* Turn off the alarm */ 1962 alarm(0); 1963 1964 if (WIFSIGNALED(status) && WTERMSIG(status) == SIGTERM && 1965 requested_transition == catatonia) { 1966 /* 1967 * /etc/rc.shutdown executed /sbin/reboot; 1968 * wait for the end quietly 1969 */ 1970 sigset_t s; 1971 1972 sigfillset(&s); 1973 for (;;) 1974 sigsuspend(&s); 1975 } 1976 1977 if (!WIFEXITED(status)) { 1978 warning("%s terminated abnormally, going to " 1979 "single user mode", _PATH_RUNDOWN); 1980 return -2; 1981 } 1982 1983 if ((status = WEXITSTATUS(status)) != 0) 1984 warning("%s returned status %d", _PATH_RUNDOWN, status); 1985 1986 return status; 1987 } 1988 1989 static char * 1990 strk(char *p) 1991 { 1992 static char *t; 1993 char *q; 1994 int c; 1995 1996 if (p) 1997 t = p; 1998 if (!t) 1999 return 0; 2000 2001 c = *t; 2002 while (c == ' ' || c == '\t' ) 2003 c = *++t; 2004 if (!c) { 2005 t = 0; 2006 return 0; 2007 } 2008 q = t; 2009 if (c == '\'') { 2010 c = *++t; 2011 q = t; 2012 while (c && c != '\'') 2013 c = *++t; 2014 if (!c) /* unterminated string */ 2015 q = t = 0; 2016 else 2017 *t++ = 0; 2018 } else { 2019 while (c && c != ' ' && c != '\t' ) 2020 c = *++t; 2021 *t++ = 0; 2022 if (!c) 2023 t = 0; 2024 } 2025 return q; 2026 } 2027 2028 #ifdef LOGIN_CAP 2029 static void 2030 setprocresources(const char *cname) 2031 { 2032 login_cap_t *lc; 2033 if ((lc = login_getclassbyname(cname, NULL)) != NULL) { 2034 setusercontext(lc, (struct passwd*)NULL, 0, 2035 LOGIN_SETENV | 2036 LOGIN_SETPRIORITY | LOGIN_SETRESOURCES | 2037 LOGIN_SETLOGINCLASS | LOGIN_SETCPUMASK); 2038 login_close(lc); 2039 } 2040 } 2041 #endif 2042