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