1/*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Donn Seeley at Berkeley Software Design, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35#include <sys/param.h> 36#include <sys/boottrace.h> 37#include <sys/ioctl.h> 38#include <sys/mman.h> 39#include <sys/mount.h> 40#include <sys/reboot.h> 41#include <sys/stat.h> 42#include <sys/sysctl.h> 43#include <sys/uio.h> 44#include <sys/wait.h> 45 46#include <db.h> 47#include <err.h> 48#include <errno.h> 49#include <fcntl.h> 50#include <kenv.h> 51#include <libutil.h> 52#include <paths.h> 53#include <signal.h> 54#include <stdarg.h> 55#include <stdbool.h> 56#include <stdio.h> 57#include <stdlib.h> 58#include <string.h> 59#include <syslog.h> 60#include <time.h> 61#include <ttyent.h> 62#include <unistd.h> 63 64#ifdef SECURE 65#include <pwd.h> 66#endif 67 68#ifdef LOGIN_CAP 69#include <login_cap.h> 70#endif 71 72#include "mntopts.h" 73#include "pathnames.h" 74 75/* 76 * Sleep times; used to prevent thrashing. 77 */ 78#define GETTY_SPACING 5 /* N secs minimum getty spacing */ 79#define GETTY_SLEEP 30 /* sleep N secs after spacing problem */ 80#define GETTY_NSPACE 3 /* max. spacing count to bring reaction */ 81#define WINDOW_WAIT 3 /* wait N secs after starting window */ 82#define STALL_TIMEOUT 30 /* wait N secs after warning */ 83#define DEATH_WATCH 10 /* wait N secs for procs to die */ 84#define DEATH_SCRIPT 120 /* wait for 2min for /etc/rc.shutdown */ 85#define RESOURCE_RC "daemon" 86#define RESOURCE_WINDOW "default" 87#define RESOURCE_GETTY "default" 88#define SCRIPT_ARGV_SIZE 3 /* size of argv passed to execute_script, can be increased if needed */ 89 90static void handle(sig_t, ...); 91static void delset(sigset_t *, ...); 92 93static void stall(const char *, ...) __printflike(1, 2); 94static void warning(const char *, ...) __printflike(1, 2); 95static void emergency(const char *, ...) __printflike(1, 2); 96static void disaster(int); 97static void revoke_ttys(void); 98static int runshutdown(void); 99static char *strk(char *); 100static void runfinal(void); 101 102/* 103 * We really need a recursive typedef... 104 * The following at least guarantees that the return type of (*state_t)() 105 * is sufficiently wide to hold a function pointer. 106 */ 107typedef long (*state_func_t)(void); 108typedef state_func_t (*state_t)(void); 109 110static state_func_t single_user(void); 111static state_func_t runcom(void); 112static state_func_t read_ttys(void); 113static state_func_t multi_user(void); 114static state_func_t clean_ttys(void); 115static state_func_t catatonia(void); 116static state_func_t death(void); 117static state_func_t death_single(void); 118static state_func_t reroot(void); 119static state_func_t reroot_phase_two(void); 120 121static state_func_t run_script(const char *); 122 123static enum { AUTOBOOT, FASTBOOT } runcom_mode = AUTOBOOT; 124 125static bool Reboot = false; 126static int howto = RB_AUTOBOOT; 127 128static bool devfs = false; 129static char *init_path_argv0; 130 131static void transition(state_t); 132static state_t requested_transition; 133static state_t current_state = death_single; 134 135static void execute_script(char *argv[]); 136static void open_console(void); 137static const char *get_shell(void); 138static void replace_init(char *path); 139static void write_stderr(const char *message); 140 141typedef struct init_session { 142 pid_t se_process; /* controlling process */ 143 time_t se_started; /* used to avoid thrashing */ 144 int se_flags; /* status of session */ 145#define SE_SHUTDOWN 0x1 /* session won't be restarted */ 146#define SE_PRESENT 0x2 /* session is in /etc/ttys */ 147#define SE_IFEXISTS 0x4 /* session defined as "onifexists" */ 148#define SE_IFCONSOLE 0x8 /* session defined as "onifconsole" */ 149 int se_nspace; /* spacing count */ 150 char *se_device; /* filename of port */ 151 char *se_getty; /* what to run on that port */ 152 char *se_getty_argv_space; /* pre-parsed argument array space */ 153 char **se_getty_argv; /* pre-parsed argument array */ 154 char *se_window; /* window system (started only once) */ 155 char *se_window_argv_space; /* pre-parsed argument array space */ 156 char **se_window_argv; /* pre-parsed argument array */ 157 char *se_type; /* default terminal type */ 158 struct init_session *se_prev; 159 struct init_session *se_next; 160} session_t; 161 162static void free_session(session_t *); 163static session_t *new_session(session_t *, struct ttyent *); 164static session_t *sessions; 165 166static char **construct_argv(char *); 167static void start_window_system(session_t *); 168static void collect_child(pid_t); 169static pid_t start_getty(session_t *); 170static void transition_handler(int); 171static void alrm_handler(int); 172static void setsecuritylevel(int); 173static int getsecuritylevel(void); 174static int setupargv(session_t *, struct ttyent *); 175#ifdef LOGIN_CAP 176static void setprocresources(const char *); 177#endif 178static bool clang; 179 180static int start_session_db(void); 181static void add_session(session_t *); 182static void del_session(session_t *); 183static session_t *find_session(pid_t); 184static DB *session_db; 185 186/* 187 * The mother of all processes. 188 */ 189int 190main(int argc, char *argv[]) 191{ 192 state_t initial_transition = runcom; 193 char kenv_value[PATH_MAX]; 194 int c, error; 195 struct sigaction sa; 196 sigset_t mask; 197 198 /* Dispose of random users. */ 199 if (getuid() != 0) 200 errx(1, "%s", strerror(EPERM)); 201 202 BOOTTRACE("init(8) starting..."); 203 204 /* System V users like to reexec init. */ 205 if (getpid() != 1) { 206#ifdef COMPAT_SYSV_INIT 207 /* So give them what they want */ 208 if (argc > 1) { 209 if (strlen(argv[1]) == 1) { 210 char runlevel = *argv[1]; 211 int sig; 212 213 switch (runlevel) { 214 case '0': /* halt + poweroff */ 215 sig = SIGUSR2; 216 break; 217 case '1': /* single-user */ 218 sig = SIGTERM; 219 break; 220 case '6': /* reboot */ 221 sig = SIGINT; 222 break; 223 case 'c': /* block further logins */ 224 sig = SIGTSTP; 225 break; 226 case 'q': /* rescan /etc/ttys */ 227 sig = SIGHUP; 228 break; 229 case 'r': /* remount root */ 230 sig = SIGEMT; 231 break; 232 default: 233 goto invalid; 234 } 235 kill(1, sig); 236 _exit(0); 237 } else 238invalid: 239 errx(1, "invalid run-level ``%s''", argv[1]); 240 } else 241#endif 242 errx(1, "already running"); 243 } 244 245 init_path_argv0 = strdup(argv[0]); 246 if (init_path_argv0 == NULL) 247 err(1, "strdup"); 248 249 /* 250 * Note that this does NOT open a file... 251 * Does 'init' deserve its own facility number? 252 */ 253 openlog("init", LOG_CONS, LOG_AUTH); 254 255 /* 256 * Create an initial session. 257 */ 258 if (setsid() < 0 && (errno != EPERM || getsid(0) != 1)) 259 warning("initial setsid() failed: %m"); 260 261 /* 262 * Establish an initial user so that programs running 263 * single user do not freak out and die (like passwd). 264 */ 265 if (setlogin("root") < 0) 266 warning("setlogin() failed: %m"); 267 268 /* 269 * This code assumes that we always get arguments through flags, 270 * never through bits set in some random machine register. 271 */ 272 while ((c = getopt(argc, argv, "dsfr")) != -1) 273 switch (c) { 274 case 'd': 275 devfs = true; 276 break; 277 case 's': 278 initial_transition = single_user; 279 break; 280 case 'f': 281 runcom_mode = FASTBOOT; 282 break; 283 case 'r': 284 initial_transition = reroot_phase_two; 285 break; 286 default: 287 warning("unrecognized flag '-%c'", c); 288 break; 289 } 290 291 if (optind != argc) 292 warning("ignoring excess arguments"); 293 294 /* 295 * We catch or block signals rather than ignore them, 296 * so that they get reset on exec. 297 */ 298 handle(disaster, SIGABRT, SIGFPE, SIGILL, SIGSEGV, SIGBUS, SIGSYS, 299 SIGXCPU, SIGXFSZ, 0); 300 handle(transition_handler, SIGHUP, SIGINT, SIGEMT, SIGTERM, SIGTSTP, 301 SIGUSR1, SIGUSR2, SIGWINCH, 0); 302 handle(alrm_handler, SIGALRM, 0); 303 sigfillset(&mask); 304 delset(&mask, SIGABRT, SIGFPE, SIGILL, SIGSEGV, SIGBUS, SIGSYS, 305 SIGXCPU, SIGXFSZ, SIGHUP, SIGINT, SIGEMT, SIGTERM, SIGTSTP, 306 SIGALRM, SIGUSR1, SIGUSR2, SIGWINCH, 0); 307 sigprocmask(SIG_SETMASK, &mask, NULL); 308 sigemptyset(&sa.sa_mask); 309 sa.sa_flags = 0; 310 sa.sa_handler = SIG_IGN; 311 sigaction(SIGTTIN, &sa, NULL); 312 sigaction(SIGTTOU, &sa, NULL); 313 314 /* 315 * Paranoia. 316 */ 317 close(0); 318 close(1); 319 close(2); 320 321 if (kenv(KENV_GET, "init_exec", kenv_value, sizeof(kenv_value)) > 0) { 322 replace_init(kenv_value); 323 _exit(0); /* reboot */ 324 } 325 326 if (kenv(KENV_GET, "init_script", kenv_value, sizeof(kenv_value)) > 0) { 327 state_func_t next_transition; 328 329 if ((next_transition = run_script(kenv_value)) != NULL) 330 initial_transition = (state_t) next_transition; 331 } 332 333 if (kenv(KENV_GET, "init_chroot", kenv_value, sizeof(kenv_value)) > 0) { 334 if (chdir(kenv_value) != 0 || chroot(".") != 0) 335 warning("Can't chroot to %s: %m", kenv_value); 336 } 337 338 /* 339 * Additional check if devfs needs to be mounted: 340 * If "/" and "/dev" have the same device number, 341 * then it hasn't been mounted yet. 342 */ 343 if (!devfs) { 344 struct stat stst; 345 dev_t root_devno; 346 347 stat("/", &stst); 348 root_devno = stst.st_dev; 349 if (stat("/dev", &stst) != 0) 350 warning("Can't stat /dev: %m"); 351 else if (stst.st_dev == root_devno) 352 devfs = true; 353 } 354 355 if (devfs) { 356 struct iovec iov[4]; 357 char *s; 358 int i; 359 360 char _fstype[] = "fstype"; 361 char _devfs[] = "devfs"; 362 char _fspath[] = "fspath"; 363 char _path_dev[]= _PATH_DEV; 364 365 iov[0].iov_base = _fstype; 366 iov[0].iov_len = sizeof(_fstype); 367 iov[1].iov_base = _devfs; 368 iov[1].iov_len = sizeof(_devfs); 369 iov[2].iov_base = _fspath; 370 iov[2].iov_len = sizeof(_fspath); 371 /* 372 * Try to avoid the trailing slash in _PATH_DEV. 373 * Be *very* defensive. 374 */ 375 s = strdup(_PATH_DEV); 376 if (s != NULL) { 377 i = strlen(s); 378 if (i > 0 && s[i - 1] == '/') 379 s[i - 1] = '\0'; 380 iov[3].iov_base = s; 381 iov[3].iov_len = strlen(s) + 1; 382 } else { 383 iov[3].iov_base = _path_dev; 384 iov[3].iov_len = sizeof(_path_dev); 385 } 386 nmount(iov, 4, 0); 387 if (s != NULL) 388 free(s); 389 } 390 391 if (initial_transition != reroot_phase_two) { 392 /* 393 * Unmount reroot leftovers. This runs after init(8) 394 * gets reexecuted after reroot_phase_two() is done. 395 */ 396 error = unmount(_PATH_REROOT, MNT_FORCE); 397 if (error != 0 && errno != EINVAL) 398 warning("Cannot unmount %s: %m", _PATH_REROOT); 399 } 400 401 /* 402 * Start the state machine. 403 */ 404 transition(initial_transition); 405 406 /* 407 * Should never reach here. 408 */ 409 return 1; 410} 411 412/* 413 * Associate a function with a signal handler. 414 */ 415static void 416handle(sig_t handler, ...) 417{ 418 int sig; 419 struct sigaction sa; 420 sigset_t mask_everything; 421 va_list ap; 422 va_start(ap, handler); 423 424 sa.sa_handler = handler; 425 sigfillset(&mask_everything); 426 427 while ((sig = va_arg(ap, int)) != 0) { 428 sa.sa_mask = mask_everything; 429 /* XXX SA_RESTART? */ 430 sa.sa_flags = sig == SIGCHLD ? SA_NOCLDSTOP : 0; 431 sigaction(sig, &sa, NULL); 432 } 433 va_end(ap); 434} 435 436/* 437 * Delete a set of signals from a mask. 438 */ 439static void 440delset(sigset_t *maskp, ...) 441{ 442 int sig; 443 va_list ap; 444 va_start(ap, maskp); 445 446 while ((sig = va_arg(ap, int)) != 0) 447 sigdelset(maskp, sig); 448 va_end(ap); 449} 450 451/* 452 * Log a message and sleep for a while (to give someone an opportunity 453 * to read it and to save log or hardcopy output if the problem is chronic). 454 * NB: should send a message to the session logger to avoid blocking. 455 */ 456static void 457stall(const char *message, ...) 458{ 459 va_list ap; 460 va_start(ap, message); 461 462 vsyslog(LOG_ALERT, message, ap); 463 va_end(ap); 464 sleep(STALL_TIMEOUT); 465} 466 467/* 468 * Like stall(), but doesn't sleep. 469 * If cpp had variadic macros, the two functions could be #defines for another. 470 * NB: should send a message to the session logger to avoid blocking. 471 */ 472static void 473warning(const char *message, ...) 474{ 475 va_list ap; 476 va_start(ap, message); 477 478 vsyslog(LOG_ALERT, message, ap); 479 va_end(ap); 480} 481 482/* 483 * Log an emergency message. 484 * NB: should send a message to the session logger to avoid blocking. 485 */ 486static void 487emergency(const char *message, ...) 488{ 489 va_list ap; 490 va_start(ap, message); 491 492 vsyslog(LOG_EMERG, message, ap); 493 va_end(ap); 494} 495 496/* 497 * Catch an unexpected signal. 498 */ 499static void 500disaster(int sig) 501{ 502 503 emergency("fatal signal: %s", 504 (unsigned)sig < NSIG ? sys_siglist[sig] : "unknown signal"); 505 506 sleep(STALL_TIMEOUT); 507 _exit(sig); /* reboot */ 508} 509 510/* 511 * Get the security level of the kernel. 512 */ 513static int 514getsecuritylevel(void) 515{ 516#ifdef KERN_SECURELVL 517 int name[2], curlevel; 518 size_t len; 519 520 name[0] = CTL_KERN; 521 name[1] = KERN_SECURELVL; 522 len = sizeof curlevel; 523 if (sysctl(name, 2, &curlevel, &len, NULL, 0) == -1) { 524 emergency("cannot get kernel security level: %m"); 525 return (-1); 526 } 527 return (curlevel); 528#else 529 return (-1); 530#endif 531} 532 533/* 534 * Set the security level of the kernel. 535 */ 536static void 537setsecuritylevel(int newlevel) 538{ 539#ifdef KERN_SECURELVL 540 int name[2], curlevel; 541 542 curlevel = getsecuritylevel(); 543 if (newlevel == curlevel) 544 return; 545 name[0] = CTL_KERN; 546 name[1] = KERN_SECURELVL; 547 if (sysctl(name, 2, NULL, NULL, &newlevel, sizeof newlevel) == -1) { 548 emergency( 549 "cannot change kernel security level from %d to %d: %m", 550 curlevel, newlevel); 551 return; 552 } 553#ifdef SECURE 554 warning("kernel security level changed from %d to %d", 555 curlevel, newlevel); 556#endif 557#endif 558} 559 560/* 561 * Change states in the finite state machine. 562 * The initial state is passed as an argument. 563 */ 564static void 565transition(state_t s) 566{ 567 568 current_state = s; 569 for (;;) 570 current_state = (state_t) (*current_state)(); 571} 572 573/* 574 * Start a session and allocate a controlling terminal. 575 * Only called by children of init after forking. 576 */ 577static void 578open_console(void) 579{ 580 int fd; 581 582 /* 583 * Try to open /dev/console. Open the device with O_NONBLOCK to 584 * prevent potential blocking on a carrier. 585 */ 586 revoke(_PATH_CONSOLE); 587 if ((fd = open(_PATH_CONSOLE, O_RDWR | O_NONBLOCK)) != -1) { 588 (void)fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) & ~O_NONBLOCK); 589 if (login_tty(fd) == 0) 590 return; 591 close(fd); 592 } 593 594 /* No luck. Log output to file if possible. */ 595 if ((fd = open(_PATH_DEVNULL, O_RDWR)) == -1) { 596 stall("cannot open null device."); 597 _exit(1); 598 } 599 if (fd != STDIN_FILENO) { 600 dup2(fd, STDIN_FILENO); 601 close(fd); 602 } 603 fd = open(_PATH_INITLOG, O_WRONLY | O_APPEND | O_CREAT, 0644); 604 if (fd == -1) 605 dup2(STDIN_FILENO, STDOUT_FILENO); 606 else if (fd != STDOUT_FILENO) { 607 dup2(fd, STDOUT_FILENO); 608 close(fd); 609 } 610 dup2(STDOUT_FILENO, STDERR_FILENO); 611} 612 613static const char * 614get_shell(void) 615{ 616 static char kenv_value[PATH_MAX]; 617 618 if (kenv(KENV_GET, "init_shell", kenv_value, sizeof(kenv_value)) > 0) 619 return kenv_value; 620 else 621 return _PATH_BSHELL; 622} 623 624static void 625write_stderr(const char *message) 626{ 627 628 write(STDERR_FILENO, message, strlen(message)); 629} 630 631static int 632read_file(const char *path, void **bufp, size_t *bufsizep) 633{ 634 struct stat sb; 635 size_t bufsize; 636 void *buf; 637 ssize_t nbytes; 638 int error, fd; 639 640 fd = open(path, O_RDONLY); 641 if (fd < 0) { 642 emergency("%s: %m", path); 643 return (-1); 644 } 645 646 error = fstat(fd, &sb); 647 if (error != 0) { 648 emergency("fstat: %m"); 649 close(fd); 650 return (error); 651 } 652 653 bufsize = sb.st_size; 654 buf = malloc(bufsize); 655 if (buf == NULL) { 656 emergency("malloc: %m"); 657 close(fd); 658 return (error); 659 } 660 661 nbytes = read(fd, buf, bufsize); 662 if (nbytes != (ssize_t)bufsize) { 663 emergency("read: %m"); 664 close(fd); 665 free(buf); 666 return (error); 667 } 668 669 error = close(fd); 670 if (error != 0) { 671 emergency("close: %m"); 672 free(buf); 673 return (error); 674 } 675 676 *bufp = buf; 677 *bufsizep = bufsize; 678 679 return (0); 680} 681 682static int 683create_file(const char *path, const void *buf, size_t bufsize) 684{ 685 ssize_t nbytes; 686 int error, fd; 687 688 fd = open(path, O_WRONLY | O_CREAT | O_EXCL, 0700); 689 if (fd < 0) { 690 emergency("%s: %m", path); 691 return (-1); 692 } 693 694 nbytes = write(fd, buf, bufsize); 695 if (nbytes != (ssize_t)bufsize) { 696 emergency("write: %m"); 697 close(fd); 698 return (-1); 699 } 700 701 error = close(fd); 702 if (error != 0) { 703 emergency("close: %m"); 704 return (-1); 705 } 706 707 return (0); 708} 709 710static int 711mount_tmpfs(const char *fspath) 712{ 713 struct iovec *iov; 714 char errmsg[255]; 715 int error, iovlen; 716 717 iov = NULL; 718 iovlen = 0; 719 memset(errmsg, 0, sizeof(errmsg)); 720 build_iovec(&iov, &iovlen, "fstype", 721 __DECONST(void *, "tmpfs"), (size_t)-1); 722 build_iovec(&iov, &iovlen, "fspath", 723 __DECONST(void *, fspath), (size_t)-1); 724 build_iovec(&iov, &iovlen, "errmsg", 725 errmsg, sizeof(errmsg)); 726 727 error = nmount(iov, iovlen, 0); 728 if (error != 0) { 729 if (*errmsg != '\0') { 730 emergency("cannot mount tmpfs on %s: %s: %m", 731 fspath, errmsg); 732 } else { 733 emergency("cannot mount tmpfs on %s: %m", 734 fspath); 735 } 736 return (error); 737 } 738 return (0); 739} 740 741static state_func_t 742reroot(void) 743{ 744 void *buf; 745 size_t bufsize; 746 int error; 747 748 buf = NULL; 749 bufsize = 0; 750 751 revoke_ttys(); 752 runshutdown(); 753 754 /* 755 * Make sure nobody can interfere with our scheme. 756 * Ignore ESRCH, which can apparently happen when 757 * there are no processes to kill. 758 */ 759 error = kill(-1, SIGKILL); 760 if (error != 0 && errno != ESRCH) { 761 emergency("kill(2) failed: %m"); 762 goto out; 763 } 764 765 /* 766 * Copy the init binary into tmpfs, so that we can unmount 767 * the old rootfs without committing suicide. 768 */ 769 error = read_file(init_path_argv0, &buf, &bufsize); 770 if (error != 0) 771 goto out; 772 error = mount_tmpfs(_PATH_REROOT); 773 if (error != 0) 774 goto out; 775 error = create_file(_PATH_REROOT_INIT, buf, bufsize); 776 if (error != 0) 777 goto out; 778 779 /* 780 * Execute the temporary init. 781 */ 782 execl(_PATH_REROOT_INIT, _PATH_REROOT_INIT, "-r", NULL); 783 emergency("cannot exec %s: %m", _PATH_REROOT_INIT); 784 785out: 786 emergency("reroot failed; going to single user mode"); 787 free(buf); 788 return (state_func_t) single_user; 789} 790 791static state_func_t 792reroot_phase_two(void) 793{ 794 char init_path[PATH_MAX], *path, *path_component; 795 size_t init_path_len; 796 int nbytes, error; 797 798 /* 799 * Ask the kernel to mount the new rootfs. 800 */ 801 error = reboot(RB_REROOT); 802 if (error != 0) { 803 emergency("RB_REBOOT failed: %m"); 804 goto out; 805 } 806 807 /* 808 * Figure out where the destination init(8) binary is. Note that 809 * the path could be different than what we've started with. Use 810 * the value from kenv, if set, or the one from sysctl otherwise. 811 * The latter defaults to a hardcoded value, but can be overridden 812 * by a build time option. 813 */ 814 nbytes = kenv(KENV_GET, "init_path", init_path, sizeof(init_path)); 815 if (nbytes <= 0) { 816 init_path_len = sizeof(init_path); 817 error = sysctlbyname("kern.init_path", 818 init_path, &init_path_len, NULL, 0); 819 if (error != 0) { 820 emergency("failed to retrieve kern.init_path: %m"); 821 goto out; 822 } 823 } 824 825 /* 826 * Repeat the init search logic from sys/kern/init_path.c 827 */ 828 path_component = init_path; 829 while ((path = strsep(&path_component, ":")) != NULL) { 830 /* 831 * Execute init(8) from the new rootfs. 832 */ 833 execl(path, path, NULL); 834 } 835 emergency("cannot exec init from %s: %m", init_path); 836 837out: 838 emergency("reroot failed; going to single user mode"); 839 return (state_func_t) single_user; 840} 841 842/* 843 * Bring the system up single user. 844 */ 845static state_func_t 846single_user(void) 847{ 848 pid_t pid, wpid; 849 int status; 850 sigset_t mask; 851 const char *shell; 852 char *argv[2]; 853 struct timeval tv, tn; 854#ifdef SECURE 855 struct ttyent *typ; 856 struct passwd *pp; 857 static const char banner[] = 858 "Enter root password, or ^D to go multi-user\n"; 859 char *clear, *password; 860#endif 861#ifdef DEBUGSHELL 862 char altshell[128]; 863#endif 864 865 if (Reboot) { 866 /* Instead of going single user, let's reboot the machine */ 867 BOOTTRACE("shutting down the system"); 868 sync(); 869 /* Run scripts after all processes have been terminated. */ 870 runfinal(); 871 if (reboot(howto) == -1) { 872 emergency("reboot(%#x) failed, %m", howto); 873 _exit(1); /* panic and reboot */ 874 } 875 warning("reboot(%#x) returned", howto); 876 _exit(0); /* panic as well */ 877 } 878 879 BOOTTRACE("going to single user mode"); 880 shell = get_shell(); 881 882 if ((pid = fork()) == 0) { 883 /* 884 * Start the single user session. 885 */ 886 open_console(); 887 888#ifdef SECURE 889 /* 890 * Check the root password. 891 * We don't care if the console is 'on' by default; 892 * it's the only tty that can be 'off' and 'secure'. 893 */ 894 typ = getttynam("console"); 895 pp = getpwnam("root"); 896 if (typ && (typ->ty_status & TTY_SECURE) == 0 && 897 pp && *pp->pw_passwd) { 898 write_stderr(banner); 899 for (;;) { 900 clear = getpass("Password:"); 901 if (clear == NULL || *clear == '\0') 902 _exit(0); 903 password = crypt(clear, pp->pw_passwd); 904 explicit_bzero(clear, _PASSWORD_LEN); 905 if (password != NULL && 906 strcmp(password, pp->pw_passwd) == 0) 907 break; 908 warning("single-user login failed\n"); 909 } 910 } 911 endttyent(); 912 endpwent(); 913#endif /* SECURE */ 914 915#ifdef DEBUGSHELL 916 { 917 char *cp = altshell; 918 int num; 919 920#define SHREQUEST "Enter full pathname of shell or RETURN for " 921 write_stderr(SHREQUEST); 922 write_stderr(shell); 923 write_stderr(": "); 924 while ((num = read(STDIN_FILENO, cp, 1)) != -1 && 925 num != 0 && *cp != '\n' && cp < &altshell[127]) 926 cp++; 927 *cp = '\0'; 928 if (altshell[0] != '\0') 929 shell = altshell; 930 } 931#endif /* DEBUGSHELL */ 932 933 /* 934 * Unblock signals. 935 * We catch all the interesting ones, 936 * and those are reset to SIG_DFL on exec. 937 */ 938 sigemptyset(&mask); 939 sigprocmask(SIG_SETMASK, &mask, NULL); 940 941 /* 942 * Fire off a shell. 943 * If the default one doesn't work, try the Bourne shell. 944 */ 945 946 char name[] = "-sh"; 947 948 argv[0] = name; 949 argv[1] = NULL; 950 execv(shell, argv); 951 emergency("can't exec %s for single user: %m", shell); 952 execv(_PATH_BSHELL, argv); 953 emergency("can't exec %s for single user: %m", _PATH_BSHELL); 954 sleep(STALL_TIMEOUT); 955 _exit(1); 956 } 957 958 if (pid == -1) { 959 /* 960 * We are seriously hosed. Do our best. 961 */ 962 emergency("can't fork single-user shell, trying again"); 963 while (waitpid(-1, (int *) 0, WNOHANG) > 0) 964 continue; 965 return (state_func_t) single_user; 966 } 967 968 requested_transition = 0; 969 do { 970 if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1) 971 collect_child(wpid); 972 if (wpid == -1) { 973 if (errno == EINTR) 974 continue; 975 warning("wait for single-user shell failed: %m; restarting"); 976 return (state_func_t) single_user; 977 } 978 if (wpid == pid && WIFSTOPPED(status)) { 979 warning("init: shell stopped, restarting\n"); 980 kill(pid, SIGCONT); 981 wpid = -1; 982 } 983 } while (wpid != pid && !requested_transition); 984 985 if (requested_transition) 986 return (state_func_t) requested_transition; 987 988 if (!WIFEXITED(status)) { 989 if (WTERMSIG(status) == SIGKILL) { 990 /* 991 * reboot(8) killed shell? 992 */ 993 warning("single user shell terminated."); 994 gettimeofday(&tv, NULL); 995 tn = tv; 996 tv.tv_sec += STALL_TIMEOUT; 997 while (tv.tv_sec > tn.tv_sec || (tv.tv_sec == 998 tn.tv_sec && tv.tv_usec > tn.tv_usec)) { 999 sleep(1); 1000 gettimeofday(&tn, NULL); 1001 } 1002 _exit(0); 1003 } else { 1004 warning("single user shell terminated, restarting"); 1005 return (state_func_t) single_user; 1006 } 1007 } 1008 1009 runcom_mode = FASTBOOT; 1010 return (state_func_t) runcom; 1011} 1012 1013/* 1014 * Run the system startup script. 1015 */ 1016static state_func_t 1017runcom(void) 1018{ 1019 state_func_t next_transition; 1020 1021 BOOTTRACE("/etc/rc starting..."); 1022 if ((next_transition = run_script(_PATH_RUNCOM)) != NULL) 1023 return next_transition; 1024 BOOTTRACE("/etc/rc finished"); 1025 1026 runcom_mode = AUTOBOOT; /* the default */ 1027 return (state_func_t) read_ttys; 1028} 1029 1030static void 1031execute_script(char *argv[]) 1032{ 1033 struct sigaction sa; 1034 char* sh_argv[3 + SCRIPT_ARGV_SIZE]; 1035 const char *shell, *script; 1036 int error, sh_argv_len, i; 1037 1038 bzero(&sa, sizeof(sa)); 1039 sigemptyset(&sa.sa_mask); 1040 sa.sa_handler = SIG_IGN; 1041 sigaction(SIGTSTP, &sa, NULL); 1042 sigaction(SIGHUP, &sa, NULL); 1043 1044 open_console(); 1045 1046 sigprocmask(SIG_SETMASK, &sa.sa_mask, NULL); 1047#ifdef LOGIN_CAP 1048 setprocresources(RESOURCE_RC); 1049#endif 1050 1051 /* 1052 * Try to directly execute the script first. If it 1053 * fails, try the old method of passing the script path 1054 * to sh(1). Don't complain if it fails because of 1055 * the missing execute bit. 1056 */ 1057 script = argv[0]; 1058 error = access(script, X_OK); 1059 if (error == 0) { 1060 execv(script, argv); 1061 warning("can't directly exec %s: %m", script); 1062 } else if (errno != EACCES) { 1063 warning("can't access %s: %m", script); 1064 } 1065 1066 shell = get_shell(); 1067 sh_argv[0] = __DECONST(char*, shell); 1068 sh_argv_len = 1; 1069#ifdef SECURE 1070 if (strcmp(shell, _PATH_BSHELL) == 0) { 1071 sh_argv[1] = __DECONST(char*, "-o"); 1072 sh_argv[2] = __DECONST(char*, "verify"); 1073 sh_argv_len = 3; 1074 } 1075#endif 1076 for (i = 0; i != SCRIPT_ARGV_SIZE; ++i) 1077 sh_argv[i + sh_argv_len] = argv[i]; 1078 execv(shell, sh_argv); 1079 stall("can't exec %s for %s: %m", shell, script); 1080} 1081 1082/* 1083 * Execute binary, replacing init(8) as PID 1. 1084 */ 1085static void 1086replace_init(char *path) 1087{ 1088 char *argv[SCRIPT_ARGV_SIZE]; 1089 1090 argv[0] = path; 1091 argv[1] = NULL; 1092 1093 execute_script(argv); 1094} 1095 1096/* 1097 * Run a shell script. 1098 * Returns 0 on success, otherwise the next transition to enter: 1099 * - single_user if fork/execv/waitpid failed, or if the script 1100 * terminated with a signal or exit code != 0. 1101 * - death_single if a SIGTERM was delivered to init(8). 1102 */ 1103static state_func_t 1104run_script(const char *script) 1105{ 1106 pid_t pid, wpid; 1107 int status; 1108 char *argv[SCRIPT_ARGV_SIZE]; 1109 const char *shell; 1110 1111 shell = get_shell(); 1112 1113 if ((pid = fork()) == 0) { 1114 1115 char _autoboot[] = "autoboot"; 1116 1117 argv[0] = __DECONST(char *, script); 1118 argv[1] = runcom_mode == AUTOBOOT ? _autoboot : NULL; 1119 argv[2] = NULL; 1120 1121 execute_script(argv); 1122 sleep(STALL_TIMEOUT); 1123 _exit(1); /* force single user mode */ 1124 } 1125 1126 if (pid == -1) { 1127 emergency("can't fork for %s on %s: %m", shell, script); 1128 while (waitpid(-1, (int *) 0, WNOHANG) > 0) 1129 continue; 1130 sleep(STALL_TIMEOUT); 1131 return (state_func_t) single_user; 1132 } 1133 1134 /* 1135 * Copied from single_user(). This is a bit paranoid. 1136 */ 1137 requested_transition = 0; 1138 do { 1139 if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1) 1140 collect_child(wpid); 1141 if (requested_transition == death_single || 1142 requested_transition == reroot) 1143 return (state_func_t) requested_transition; 1144 if (wpid == -1) { 1145 if (errno == EINTR) 1146 continue; 1147 warning("wait for %s on %s failed: %m; going to " 1148 "single user mode", shell, script); 1149 return (state_func_t) single_user; 1150 } 1151 if (wpid == pid && WIFSTOPPED(status)) { 1152 warning("init: %s on %s stopped, restarting\n", 1153 shell, script); 1154 kill(pid, SIGCONT); 1155 wpid = -1; 1156 } 1157 } while (wpid != pid); 1158 1159 if (WIFSIGNALED(status) && WTERMSIG(status) == SIGTERM && 1160 requested_transition == catatonia) { 1161 /* /etc/rc executed /sbin/reboot; wait for the end quietly */ 1162 sigset_t s; 1163 1164 sigfillset(&s); 1165 for (;;) 1166 sigsuspend(&s); 1167 } 1168 1169 if (!WIFEXITED(status)) { 1170 warning("%s on %s terminated abnormally, going to single " 1171 "user mode", shell, script); 1172 return (state_func_t) single_user; 1173 } 1174 1175 if (WEXITSTATUS(status)) 1176 return (state_func_t) single_user; 1177 1178 return (state_func_t) 0; 1179} 1180 1181/* 1182 * Open the session database. 1183 * 1184 * NB: We could pass in the size here; is it necessary? 1185 */ 1186static int 1187start_session_db(void) 1188{ 1189 if (session_db && (*session_db->close)(session_db)) 1190 emergency("session database close: %m"); 1191 if ((session_db = dbopen(NULL, O_RDWR, 0, DB_HASH, NULL)) == NULL) { 1192 emergency("session database open: %m"); 1193 return (1); 1194 } 1195 return (0); 1196 1197} 1198 1199/* 1200 * Add a new login session. 1201 */ 1202static void 1203add_session(session_t *sp) 1204{ 1205 DBT key; 1206 DBT data; 1207 1208 key.data = &sp->se_process; 1209 key.size = sizeof sp->se_process; 1210 data.data = &sp; 1211 data.size = sizeof sp; 1212 1213 if ((*session_db->put)(session_db, &key, &data, 0)) 1214 emergency("insert %d: %m", sp->se_process); 1215} 1216 1217/* 1218 * Delete an old login session. 1219 */ 1220static void 1221del_session(session_t *sp) 1222{ 1223 DBT key; 1224 1225 key.data = &sp->se_process; 1226 key.size = sizeof sp->se_process; 1227 1228 if ((*session_db->del)(session_db, &key, 0)) 1229 emergency("delete %d: %m", sp->se_process); 1230} 1231 1232/* 1233 * Look up a login session by pid. 1234 */ 1235static session_t * 1236find_session(pid_t pid) 1237{ 1238 DBT key; 1239 DBT data; 1240 session_t *ret; 1241 1242 key.data = &pid; 1243 key.size = sizeof pid; 1244 if ((*session_db->get)(session_db, &key, &data, 0) != 0) 1245 return 0; 1246 bcopy(data.data, (char *)&ret, sizeof(ret)); 1247 return ret; 1248} 1249 1250/* 1251 * Construct an argument vector from a command line. 1252 */ 1253static char ** 1254construct_argv(char *command) 1255{ 1256 int argc = 0; 1257 char **argv = (char **) malloc(((strlen(command) + 1) / 2 + 1) 1258 * sizeof (char *)); 1259 1260 if ((argv[argc++] = strk(command)) == NULL) { 1261 free(argv); 1262 return (NULL); 1263 } 1264 while ((argv[argc++] = strk((char *) 0)) != NULL) 1265 continue; 1266 return argv; 1267} 1268 1269/* 1270 * Deallocate a session descriptor. 1271 */ 1272static void 1273free_session(session_t *sp) 1274{ 1275 free(sp->se_device); 1276 if (sp->se_getty) { 1277 free(sp->se_getty); 1278 free(sp->se_getty_argv_space); 1279 free(sp->se_getty_argv); 1280 } 1281 if (sp->se_window) { 1282 free(sp->se_window); 1283 free(sp->se_window_argv_space); 1284 free(sp->se_window_argv); 1285 } 1286 if (sp->se_type) 1287 free(sp->se_type); 1288 free(sp); 1289} 1290 1291/* 1292 * Allocate a new session descriptor. 1293 * Mark it SE_PRESENT. 1294 */ 1295static session_t * 1296new_session(session_t *sprev, struct ttyent *typ) 1297{ 1298 session_t *sp; 1299 1300 if ((typ->ty_status & TTY_ON) == 0 || 1301 typ->ty_name == 0 || 1302 typ->ty_getty == 0) 1303 return 0; 1304 1305 sp = (session_t *) calloc(1, sizeof (session_t)); 1306 1307 sp->se_flags |= SE_PRESENT; 1308 1309 if ((typ->ty_status & TTY_IFEXISTS) != 0) 1310 sp->se_flags |= SE_IFEXISTS; 1311 1312 if ((typ->ty_status & TTY_IFCONSOLE) != 0) 1313 sp->se_flags |= SE_IFCONSOLE; 1314 1315 if (asprintf(&sp->se_device, "%s%s", _PATH_DEV, typ->ty_name) < 0) 1316 err(1, "asprintf"); 1317 1318 if (setupargv(sp, typ) == 0) { 1319 free_session(sp); 1320 return (0); 1321 } 1322 1323 sp->se_next = 0; 1324 if (sprev == NULL) { 1325 sessions = sp; 1326 sp->se_prev = 0; 1327 } else { 1328 sprev->se_next = sp; 1329 sp->se_prev = sprev; 1330 } 1331 1332 return sp; 1333} 1334 1335/* 1336 * Calculate getty and if useful window argv vectors. 1337 */ 1338static int 1339setupargv(session_t *sp, struct ttyent *typ) 1340{ 1341 1342 if (sp->se_getty) { 1343 free(sp->se_getty); 1344 free(sp->se_getty_argv_space); 1345 free(sp->se_getty_argv); 1346 } 1347 if (asprintf(&sp->se_getty, "%s %s", typ->ty_getty, typ->ty_name) < 0) 1348 err(1, "asprintf"); 1349 sp->se_getty_argv_space = strdup(sp->se_getty); 1350 sp->se_getty_argv = construct_argv(sp->se_getty_argv_space); 1351 if (sp->se_getty_argv == NULL) { 1352 warning("can't parse getty for port %s", sp->se_device); 1353 free(sp->se_getty); 1354 free(sp->se_getty_argv_space); 1355 sp->se_getty = sp->se_getty_argv_space = 0; 1356 return (0); 1357 } 1358 if (sp->se_window) { 1359 free(sp->se_window); 1360 free(sp->se_window_argv_space); 1361 free(sp->se_window_argv); 1362 } 1363 sp->se_window = sp->se_window_argv_space = 0; 1364 sp->se_window_argv = 0; 1365 if (typ->ty_window) { 1366 sp->se_window = strdup(typ->ty_window); 1367 sp->se_window_argv_space = strdup(sp->se_window); 1368 sp->se_window_argv = construct_argv(sp->se_window_argv_space); 1369 if (sp->se_window_argv == NULL) { 1370 warning("can't parse window for port %s", 1371 sp->se_device); 1372 free(sp->se_window_argv_space); 1373 free(sp->se_window); 1374 sp->se_window = sp->se_window_argv_space = 0; 1375 return (0); 1376 } 1377 } 1378 if (sp->se_type) 1379 free(sp->se_type); 1380 sp->se_type = typ->ty_type ? strdup(typ->ty_type) : 0; 1381 return (1); 1382} 1383 1384/* 1385 * Walk the list of ttys and create sessions for each active line. 1386 */ 1387static state_func_t 1388read_ttys(void) 1389{ 1390 session_t *sp, *snext; 1391 struct ttyent *typ; 1392 1393 /* 1394 * Destroy any previous session state. 1395 * There shouldn't be any, but just in case... 1396 */ 1397 for (sp = sessions; sp; sp = snext) { 1398 snext = sp->se_next; 1399 free_session(sp); 1400 } 1401 sessions = 0; 1402 if (start_session_db()) 1403 return (state_func_t) single_user; 1404 1405 /* 1406 * Allocate a session entry for each active port. 1407 * Note that sp starts at 0. 1408 */ 1409 while ((typ = getttyent()) != NULL) 1410 if ((snext = new_session(sp, typ)) != NULL) 1411 sp = snext; 1412 1413 endttyent(); 1414 1415 return (state_func_t) multi_user; 1416} 1417 1418/* 1419 * Start a window system running. 1420 */ 1421static void 1422start_window_system(session_t *sp) 1423{ 1424 pid_t pid; 1425 sigset_t mask; 1426 char term[64], *env[2]; 1427 int status; 1428 1429 if ((pid = fork()) == -1) { 1430 emergency("can't fork for window system on port %s: %m", 1431 sp->se_device); 1432 /* hope that getty fails and we can try again */ 1433 return; 1434 } 1435 if (pid) { 1436 waitpid(-1, &status, 0); 1437 return; 1438 } 1439 1440 /* reparent window process to the init to not make a zombie on exit */ 1441 if ((pid = fork()) == -1) { 1442 emergency("can't fork for window system on port %s: %m", 1443 sp->se_device); 1444 _exit(1); 1445 } 1446 if (pid) 1447 _exit(0); 1448 1449 sigemptyset(&mask); 1450 sigprocmask(SIG_SETMASK, &mask, NULL); 1451 1452 if (setsid() < 0) 1453 emergency("setsid failed (window) %m"); 1454 1455#ifdef LOGIN_CAP 1456 setprocresources(RESOURCE_WINDOW); 1457#endif 1458 if (sp->se_type) { 1459 /* Don't use malloc after fork */ 1460 strcpy(term, "TERM="); 1461 strlcat(term, sp->se_type, sizeof(term)); 1462 env[0] = term; 1463 env[1] = NULL; 1464 } 1465 else 1466 env[0] = NULL; 1467 execve(sp->se_window_argv[0], sp->se_window_argv, env); 1468 stall("can't exec window system '%s' for port %s: %m", 1469 sp->se_window_argv[0], sp->se_device); 1470 _exit(1); 1471} 1472 1473/* 1474 * Start a login session running. 1475 */ 1476static pid_t 1477start_getty(session_t *sp) 1478{ 1479 pid_t pid; 1480 sigset_t mask; 1481 time_t current_time = time((time_t *) 0); 1482 int too_quick = 0; 1483 char term[64], *env[2]; 1484 1485 if (current_time >= sp->se_started && 1486 current_time - sp->se_started < GETTY_SPACING) { 1487 if (++sp->se_nspace > GETTY_NSPACE) { 1488 sp->se_nspace = 0; 1489 too_quick = 1; 1490 } 1491 } else 1492 sp->se_nspace = 0; 1493 1494 /* 1495 * fork(), not vfork() -- we can't afford to block. 1496 */ 1497 if ((pid = fork()) == -1) { 1498 emergency("can't fork for getty on port %s: %m", sp->se_device); 1499 return -1; 1500 } 1501 1502 if (pid) 1503 return pid; 1504 1505 if (too_quick) { 1506 warning("getty repeating too quickly on port %s, sleeping %d secs", 1507 sp->se_device, GETTY_SLEEP); 1508 sleep((unsigned) GETTY_SLEEP); 1509 } 1510 1511 if (sp->se_window) { 1512 start_window_system(sp); 1513 sleep(WINDOW_WAIT); 1514 } 1515 1516 sigemptyset(&mask); 1517 sigprocmask(SIG_SETMASK, &mask, NULL); 1518 1519#ifdef LOGIN_CAP 1520 setprocresources(RESOURCE_GETTY); 1521#endif 1522 if (sp->se_type) { 1523 /* Don't use malloc after fork */ 1524 strcpy(term, "TERM="); 1525 strlcat(term, sp->se_type, sizeof(term)); 1526 env[0] = term; 1527 env[1] = NULL; 1528 } else 1529 env[0] = NULL; 1530 execve(sp->se_getty_argv[0], sp->se_getty_argv, env); 1531 stall("can't exec getty '%s' for port %s: %m", 1532 sp->se_getty_argv[0], sp->se_device); 1533 _exit(1); 1534} 1535 1536/* 1537 * Return 1 if the session is defined as "onifexists" 1538 * or "onifconsole" and the device node does not exist. 1539 */ 1540static int 1541session_has_no_tty(session_t *sp) 1542{ 1543 int fd; 1544 1545 if ((sp->se_flags & SE_IFEXISTS) == 0 && 1546 (sp->se_flags & SE_IFCONSOLE) == 0) 1547 return (0); 1548 1549 fd = open(sp->se_device, O_RDONLY | O_NONBLOCK, 0); 1550 if (fd < 0) { 1551 if (errno == ENOENT) 1552 return (1); 1553 return (0); 1554 } 1555 1556 close(fd); 1557 return (0); 1558} 1559 1560/* 1561 * Collect exit status for a child. 1562 * If an exiting login, start a new login running. 1563 */ 1564static void 1565collect_child(pid_t pid) 1566{ 1567 session_t *sp, *sprev, *snext; 1568 1569 if (! sessions) 1570 return; 1571 1572 if (! (sp = find_session(pid))) 1573 return; 1574 1575 del_session(sp); 1576 sp->se_process = 0; 1577 1578 if (sp->se_flags & SE_SHUTDOWN || 1579 session_has_no_tty(sp)) { 1580 if ((sprev = sp->se_prev) != NULL) 1581 sprev->se_next = sp->se_next; 1582 else 1583 sessions = sp->se_next; 1584 if ((snext = sp->se_next) != NULL) 1585 snext->se_prev = sp->se_prev; 1586 free_session(sp); 1587 return; 1588 } 1589 1590 if ((pid = start_getty(sp)) == -1) { 1591 /* serious trouble */ 1592 requested_transition = clean_ttys; 1593 return; 1594 } 1595 1596 sp->se_process = pid; 1597 sp->se_started = time((time_t *) 0); 1598 add_session(sp); 1599} 1600 1601static const char * 1602get_current_state(void) 1603{ 1604 1605 if (current_state == single_user) 1606 return ("single-user"); 1607 if (current_state == runcom) 1608 return ("runcom"); 1609 if (current_state == read_ttys) 1610 return ("read-ttys"); 1611 if (current_state == multi_user) 1612 return ("multi-user"); 1613 if (current_state == clean_ttys) 1614 return ("clean-ttys"); 1615 if (current_state == catatonia) 1616 return ("catatonia"); 1617 if (current_state == death) 1618 return ("death"); 1619 if (current_state == death_single) 1620 return ("death-single"); 1621 return ("unknown"); 1622} 1623 1624static void 1625boottrace_transition(int sig) 1626{ 1627 const char *action; 1628 1629 switch (sig) { 1630 case SIGUSR2: 1631 action = "halt & poweroff"; 1632 break; 1633 case SIGUSR1: 1634 action = "halt"; 1635 break; 1636 case SIGINT: 1637 action = "reboot"; 1638 break; 1639 case SIGWINCH: 1640 action = "powercycle"; 1641 break; 1642 case SIGTERM: 1643 action = Reboot ? "reboot" : "single-user"; 1644 break; 1645 default: 1646 BOOTTRACE("signal %d from %s", sig, get_current_state()); 1647 return; 1648 } 1649 1650 /* Trace the shutdown reason. */ 1651 SHUTTRACE("%s from %s", action, get_current_state()); 1652} 1653 1654/* 1655 * Catch a signal and request a state transition. 1656 */ 1657static void 1658transition_handler(int sig) 1659{ 1660 1661 boottrace_transition(sig); 1662 switch (sig) { 1663 case SIGHUP: 1664 if (current_state == read_ttys || current_state == multi_user || 1665 current_state == clean_ttys || current_state == catatonia) 1666 requested_transition = clean_ttys; 1667 break; 1668 case SIGUSR2: 1669 howto = RB_POWEROFF; 1670 case SIGUSR1: 1671 howto |= RB_HALT; 1672 case SIGWINCH: 1673 case SIGINT: 1674 if (sig == SIGWINCH) 1675 howto |= RB_POWERCYCLE; 1676 Reboot = true; 1677 case SIGTERM: 1678 if (current_state == read_ttys || current_state == multi_user || 1679 current_state == clean_ttys || current_state == catatonia) 1680 requested_transition = death; 1681 else 1682 requested_transition = death_single; 1683 break; 1684 case SIGTSTP: 1685 if (current_state == runcom || current_state == read_ttys || 1686 current_state == clean_ttys || 1687 current_state == multi_user || current_state == catatonia) 1688 requested_transition = catatonia; 1689 break; 1690 case SIGEMT: 1691 requested_transition = reroot; 1692 break; 1693 default: 1694 requested_transition = 0; 1695 break; 1696 } 1697} 1698 1699/* 1700 * Take the system multiuser. 1701 */ 1702static state_func_t 1703multi_user(void) 1704{ 1705 static bool inmultiuser = false; 1706 pid_t pid; 1707 session_t *sp; 1708 1709 requested_transition = 0; 1710 1711 /* 1712 * If the administrator has not set the security level to -1 1713 * to indicate that the kernel should not run multiuser in secure 1714 * mode, and the run script has not set a higher level of security 1715 * than level 1, then put the kernel into secure mode. 1716 */ 1717 if (getsecuritylevel() == 0) 1718 setsecuritylevel(1); 1719 1720 for (sp = sessions; sp; sp = sp->se_next) { 1721 if (sp->se_process) 1722 continue; 1723 if (session_has_no_tty(sp)) 1724 continue; 1725 if ((pid = start_getty(sp)) == -1) { 1726 /* serious trouble */ 1727 requested_transition = clean_ttys; 1728 break; 1729 } 1730 sp->se_process = pid; 1731 sp->se_started = time((time_t *) 0); 1732 add_session(sp); 1733 } 1734 1735 if (requested_transition == 0 && !inmultiuser) { 1736 inmultiuser = true; 1737 /* This marks the change from boot-time tracing to run-time. */ 1738 RUNTRACE("multi-user start"); 1739 } 1740 while (!requested_transition) 1741 if ((pid = waitpid(-1, (int *) 0, 0)) != -1) 1742 collect_child(pid); 1743 1744 return (state_func_t) requested_transition; 1745} 1746 1747/* 1748 * This is an (n*2)+(n^2) algorithm. We hope it isn't run often... 1749 */ 1750static state_func_t 1751clean_ttys(void) 1752{ 1753 session_t *sp, *sprev; 1754 struct ttyent *typ; 1755 int devlen; 1756 char *old_getty, *old_window, *old_type; 1757 1758 /* 1759 * mark all sessions for death, (!SE_PRESENT) 1760 * as we find or create new ones they'll be marked as keepers, 1761 * we'll later nuke all the ones not found in /etc/ttys 1762 */ 1763 for (sp = sessions; sp != NULL; sp = sp->se_next) 1764 sp->se_flags &= ~SE_PRESENT; 1765 1766 devlen = sizeof(_PATH_DEV) - 1; 1767 while ((typ = getttyent()) != NULL) { 1768 for (sprev = 0, sp = sessions; sp; sprev = sp, sp = sp->se_next) 1769 if (strcmp(typ->ty_name, sp->se_device + devlen) == 0) 1770 break; 1771 1772 if (sp) { 1773 /* we want this one to live */ 1774 sp->se_flags |= SE_PRESENT; 1775 if ((typ->ty_status & TTY_ON) == 0 || 1776 typ->ty_getty == 0) { 1777 sp->se_flags |= SE_SHUTDOWN; 1778 kill(sp->se_process, SIGHUP); 1779 continue; 1780 } 1781 sp->se_flags &= ~SE_SHUTDOWN; 1782 old_getty = sp->se_getty ? strdup(sp->se_getty) : 0; 1783 old_window = sp->se_window ? strdup(sp->se_window) : 0; 1784 old_type = sp->se_type ? strdup(sp->se_type) : 0; 1785 if (setupargv(sp, typ) == 0) { 1786 warning("can't parse getty for port %s", 1787 sp->se_device); 1788 sp->se_flags |= SE_SHUTDOWN; 1789 kill(sp->se_process, SIGHUP); 1790 } 1791 else if ( !old_getty 1792 || (!old_type && sp->se_type) 1793 || (old_type && !sp->se_type) 1794 || (!old_window && sp->se_window) 1795 || (old_window && !sp->se_window) 1796 || (strcmp(old_getty, sp->se_getty) != 0) 1797 || (old_window && strcmp(old_window, sp->se_window) != 0) 1798 || (old_type && strcmp(old_type, sp->se_type) != 0) 1799 ) { 1800 /* Don't set SE_SHUTDOWN here */ 1801 sp->se_nspace = 0; 1802 sp->se_started = 0; 1803 kill(sp->se_process, SIGHUP); 1804 } 1805 if (old_getty) 1806 free(old_getty); 1807 if (old_window) 1808 free(old_window); 1809 if (old_type) 1810 free(old_type); 1811 continue; 1812 } 1813 1814 new_session(sprev, typ); 1815 } 1816 1817 endttyent(); 1818 1819 /* 1820 * sweep through and kill all deleted sessions 1821 * ones who's /etc/ttys line was deleted (SE_PRESENT unset) 1822 */ 1823 for (sp = sessions; sp != NULL; sp = sp->se_next) { 1824 if ((sp->se_flags & SE_PRESENT) == 0) { 1825 sp->se_flags |= SE_SHUTDOWN; 1826 kill(sp->se_process, SIGHUP); 1827 } 1828 } 1829 1830 return (state_func_t) multi_user; 1831} 1832 1833/* 1834 * Block further logins. 1835 */ 1836static state_func_t 1837catatonia(void) 1838{ 1839 session_t *sp; 1840 1841 for (sp = sessions; sp; sp = sp->se_next) 1842 sp->se_flags |= SE_SHUTDOWN; 1843 1844 return (state_func_t) multi_user; 1845} 1846 1847/* 1848 * Note SIGALRM. 1849 */ 1850static void 1851alrm_handler(int sig) 1852{ 1853 1854 (void)sig; 1855 clang = true; 1856} 1857 1858/* 1859 * Bring the system down to single user. 1860 */ 1861static state_func_t 1862death(void) 1863{ 1864 int block, blocked; 1865 size_t len; 1866 1867 /* Temporarily block suspend. */ 1868 len = sizeof(blocked); 1869 block = 1; 1870 if (sysctlbyname("kern.suspend_blocked", &blocked, &len, 1871 &block, sizeof(block)) == -1) 1872 blocked = 0; 1873 1874 /* 1875 * Also revoke the TTY here. Because runshutdown() may reopen 1876 * the TTY whose getty we're killing here, there is no guarantee 1877 * runshutdown() will perform the initial open() call, causing 1878 * the terminal attributes to be misconfigured. 1879 */ 1880 revoke_ttys(); 1881 1882 /* Try to run the rc.shutdown script within a period of time */ 1883 runshutdown(); 1884 1885 /* Unblock suspend if we blocked it. */ 1886 if (!blocked) 1887 sysctlbyname("kern.suspend_blocked", NULL, NULL, 1888 &blocked, sizeof(blocked)); 1889 1890 return (state_func_t) death_single; 1891} 1892 1893/* 1894 * Do what is necessary to reinitialize single user mode or reboot 1895 * from an incomplete state. 1896 */ 1897static state_func_t 1898death_single(void) 1899{ 1900 int i; 1901 pid_t pid; 1902 static const int death_sigs[2] = { SIGTERM, SIGKILL }; 1903 1904 revoke(_PATH_CONSOLE); 1905 1906 BOOTTRACE("start killing user processes"); 1907 for (i = 0; i < 2; ++i) { 1908 if (kill(-1, death_sigs[i]) == -1 && errno == ESRCH) 1909 return (state_func_t) single_user; 1910 1911 clang = false; 1912 alarm(DEATH_WATCH); 1913 do 1914 if ((pid = waitpid(-1, (int *)0, 0)) != -1) 1915 collect_child(pid); 1916 while (!clang && errno != ECHILD); 1917 1918 if (errno == ECHILD) 1919 return (state_func_t) single_user; 1920 } 1921 1922 warning("some processes would not die; ps axl advised"); 1923 1924 return (state_func_t) single_user; 1925} 1926 1927static void 1928revoke_ttys(void) 1929{ 1930 session_t *sp; 1931 1932 for (sp = sessions; sp; sp = sp->se_next) { 1933 sp->se_flags |= SE_SHUTDOWN; 1934 kill(sp->se_process, SIGHUP); 1935 revoke(sp->se_device); 1936 } 1937} 1938 1939/* 1940 * Run the system shutdown script. 1941 * 1942 * Exit codes: XXX I should document more 1943 * -2 shutdown script terminated abnormally 1944 * -1 fatal error - can't run script 1945 * 0 good. 1946 * >0 some error (exit code) 1947 */ 1948static int 1949runshutdown(void) 1950{ 1951 pid_t pid, wpid; 1952 int status; 1953 int shutdowntimeout; 1954 size_t len; 1955 char *argv[SCRIPT_ARGV_SIZE]; 1956 struct stat sb; 1957 1958 BOOTTRACE("init(8): start rc.shutdown"); 1959 1960 /* 1961 * rc.shutdown is optional, so to prevent any unnecessary 1962 * complaints from the shell we simply don't run it if the 1963 * file does not exist. If the stat() here fails for other 1964 * reasons, we'll let the shell complain. 1965 */ 1966 if (stat(_PATH_RUNDOWN, &sb) == -1 && errno == ENOENT) 1967 return 0; 1968 1969 if ((pid = fork()) == 0) { 1970 char _reboot[] = "reboot"; 1971 char _single[] = "single"; 1972 char _path_rundown[] = _PATH_RUNDOWN; 1973 1974 argv[0] = _path_rundown; 1975 argv[1] = Reboot ? _reboot : _single; 1976 argv[2] = NULL; 1977 1978 execute_script(argv); 1979 _exit(1); /* force single user mode */ 1980 } 1981 1982 if (pid == -1) { 1983 emergency("can't fork for %s: %m", _PATH_RUNDOWN); 1984 while (waitpid(-1, (int *) 0, WNOHANG) > 0) 1985 continue; 1986 sleep(STALL_TIMEOUT); 1987 return -1; 1988 } 1989 1990 len = sizeof(shutdowntimeout); 1991 if (sysctlbyname("kern.init_shutdown_timeout", &shutdowntimeout, &len, 1992 NULL, 0) == -1 || shutdowntimeout < 2) 1993 shutdowntimeout = DEATH_SCRIPT; 1994 alarm(shutdowntimeout); 1995 clang = false; 1996 /* 1997 * Copied from single_user(). This is a bit paranoid. 1998 * Use the same ALRM handler. 1999 */ 2000 do { 2001 if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1) 2002 collect_child(wpid); 2003 if (clang) { 2004 /* we were waiting for the sub-shell */ 2005 kill(wpid, SIGTERM); 2006 warning("timeout expired for %s: %m; going to " 2007 "single user mode", _PATH_RUNDOWN); 2008 BOOTTRACE("rc.shutdown's %d sec timeout expired", 2009 shutdowntimeout); 2010 return -1; 2011 } 2012 if (wpid == -1) { 2013 if (errno == EINTR) 2014 continue; 2015 warning("wait for %s failed: %m; going to " 2016 "single user mode", _PATH_RUNDOWN); 2017 return -1; 2018 } 2019 if (wpid == pid && WIFSTOPPED(status)) { 2020 warning("init: %s stopped, restarting\n", 2021 _PATH_RUNDOWN); 2022 kill(pid, SIGCONT); 2023 wpid = -1; 2024 } 2025 } while (wpid != pid && !clang); 2026 2027 /* Turn off the alarm */ 2028 alarm(0); 2029 2030 if (WIFSIGNALED(status) && WTERMSIG(status) == SIGTERM && 2031 requested_transition == catatonia) { 2032 /* 2033 * /etc/rc.shutdown executed /sbin/reboot; 2034 * wait for the end quietly 2035 */ 2036 sigset_t s; 2037 2038 sigfillset(&s); 2039 for (;;) 2040 sigsuspend(&s); 2041 } 2042 2043 if (!WIFEXITED(status)) { 2044 warning("%s terminated abnormally, going to " 2045 "single user mode", _PATH_RUNDOWN); 2046 return -2; 2047 } 2048 2049 if ((status = WEXITSTATUS(status)) != 0) 2050 warning("%s returned status %d", _PATH_RUNDOWN, status); 2051 2052 return status; 2053} 2054 2055static char * 2056strk(char *p) 2057{ 2058 static char *t; 2059 char *q; 2060 int c; 2061 2062 if (p) 2063 t = p; 2064 if (!t) 2065 return 0; 2066 2067 c = *t; 2068 while (c == ' ' || c == '\t' ) 2069 c = *++t; 2070 if (!c) { 2071 t = 0; 2072 return 0; 2073 } 2074 q = t; 2075 if (c == '\'') { 2076 c = *++t; 2077 q = t; 2078 while (c && c != '\'') 2079 c = *++t; 2080 if (!c) /* unterminated string */ 2081 q = t = 0; 2082 else 2083 *t++ = 0; 2084 } else { 2085 while (c && c != ' ' && c != '\t' ) 2086 c = *++t; 2087 *t++ = 0; 2088 if (!c) 2089 t = 0; 2090 } 2091 return q; 2092} 2093 2094#ifdef LOGIN_CAP 2095static void 2096setprocresources(const char *cname) 2097{ 2098 login_cap_t *lc; 2099 if ((lc = login_getclassbyname(cname, NULL)) != NULL) { 2100 setusercontext(lc, (struct passwd*)NULL, 0, 2101 LOGIN_SETENV | 2102 LOGIN_SETPRIORITY | LOGIN_SETRESOURCES | 2103 LOGIN_SETLOGINCLASS | LOGIN_SETCPUMASK); 2104 login_close(lc); 2105 } 2106} 2107#endif 2108 2109/* 2110 * Run /etc/rc.final to execute scripts after all user processes have been 2111 * terminated. 2112 */ 2113static void 2114runfinal(void) 2115{ 2116 struct stat sb; 2117 pid_t other_pid, pid; 2118 sigset_t mask; 2119 2120 /* Avoid any surprises. */ 2121 alarm(0); 2122 2123 /* rc.final is optional. */ 2124 if (stat(_PATH_RUNFINAL, &sb) == -1 && errno == ENOENT) 2125 return; 2126 if (access(_PATH_RUNFINAL, X_OK) != 0) { 2127 warning("%s exists, but not executable", _PATH_RUNFINAL); 2128 return; 2129 } 2130 2131 pid = fork(); 2132 if (pid == 0) { 2133 /* 2134 * Reopen stdin/stdout/stderr so that scripts can write to 2135 * console. 2136 */ 2137 close(0); 2138 open(_PATH_DEVNULL, O_RDONLY); 2139 close(1); 2140 close(2); 2141 open_console(); 2142 dup2(1, 2); 2143 sigemptyset(&mask); 2144 sigprocmask(SIG_SETMASK, &mask, NULL); 2145 signal(SIGCHLD, SIG_DFL); 2146 execl(_PATH_RUNFINAL, _PATH_RUNFINAL, NULL); 2147 perror("execl(" _PATH_RUNFINAL ") failed"); 2148 exit(1); 2149 } 2150 2151 /* Wait for rc.final script to exit */ 2152 while ((other_pid = waitpid(-1, NULL, 0)) != pid && other_pid > 0) { 2153 continue; 2154 } 2155} 2156