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