1/*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Donn Seeley at Berkeley Software Design, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35#ifndef lint 36static const char copyright[] = 37"@(#) Copyright (c) 1991, 1993\n\ 38 The Regents of the University of California. All rights reserved.\n"; 39#endif /* not lint */ 40 41#ifndef lint 42#if 0 43static char sccsid[] = "@(#)init.c 8.1 (Berkeley) 7/15/93"; 44#endif 45static const char rcsid[] = 46 "$FreeBSD$"; 47#endif /* not lint */ 48 49#include <sys/param.h> 50#include <sys/ioctl.h> 51#include <sys/mman.h> 52#include <sys/mount.h> 53#include <sys/sysctl.h> 54#include <sys/wait.h> 55#include <sys/stat.h> 56#include <sys/uio.h> 57 58#include <db.h> 59#include <errno.h> 60#include <fcntl.h> 61#include <kenv.h> 62#include <libutil.h> 63#include <paths.h> 64#include <signal.h> 65#include <stdio.h> 66#include <stdlib.h> 67#include <string.h> 68#include <syslog.h> 69#include <time.h> 70#include <ttyent.h> 71#include <unistd.h> 72#include <sys/reboot.h> 73#include <err.h> 74 75#include <stdarg.h> 76 77#ifdef SECURE 78#include <pwd.h> 79#endif 80 81#ifdef LOGIN_CAP 82#include <login_cap.h> 83#endif 84 85#include "mntopts.h" 86#include "pathnames.h" 87 88/* 89 * Sleep times; used to prevent thrashing. 90 */ 91#define GETTY_SPACING 5 /* N secs minimum getty spacing */ 92#define GETTY_SLEEP 30 /* sleep N secs after spacing problem */ 93#define GETTY_NSPACE 3 /* max. spacing count to bring reaction */ 94#define WINDOW_WAIT 3 /* wait N secs after starting window */ 95#define STALL_TIMEOUT 30 /* wait N secs after warning */ 96#define DEATH_WATCH 10 /* wait N secs for procs to die */ 97#define DEATH_SCRIPT 120 /* wait for 2min for /etc/rc.shutdown */ 98#define RESOURCE_RC "daemon" 99#define RESOURCE_WINDOW "default" 100#define RESOURCE_GETTY "default" 101 102static void handle(sig_t, ...); 103static void delset(sigset_t *, ...); 104 105static void stall(const char *, ...) __printflike(1, 2); 106static void warning(const char *, ...) __printflike(1, 2); 107static void emergency(const char *, ...) __printflike(1, 2); 108static void disaster(int); 109static void revoke_ttys(void); 110static int runshutdown(void); 111static char *strk(char *); 112 113/* 114 * We really need a recursive typedef... 115 * The following at least guarantees that the return type of (*state_t)() 116 * is sufficiently wide to hold a function pointer. 117 */ 118typedef long (*state_func_t)(void); 119typedef state_func_t (*state_t)(void); 120 121static state_func_t single_user(void); 122static state_func_t runcom(void); 123static state_func_t read_ttys(void); 124static state_func_t multi_user(void); 125static state_func_t clean_ttys(void); 126static state_func_t catatonia(void); 127static state_func_t death(void); 128static state_func_t death_single(void); 129static state_func_t reroot(void); 130static state_func_t reroot_phase_two(void); 131 132static state_func_t run_script(const char *); 133 134static enum { AUTOBOOT, FASTBOOT } runcom_mode = AUTOBOOT; 135#define FALSE 0 136#define TRUE 1 137 138static int Reboot = FALSE; 139static int howto = RB_AUTOBOOT; 140 141static int devfs; 142static char *init_path_argv0; 143 144static void transition(state_t); 145static state_t requested_transition; 146static state_t current_state = death_single; 147 148static void execute_script(char *argv[]); 149static void open_console(void); 150static const char *get_shell(void); 151static void replace_init(char *path); 152static void write_stderr(const char *message); 153 154typedef struct init_session { 155 pid_t se_process; /* controlling process */ 156 time_t se_started; /* used to avoid thrashing */ 157 int se_flags; /* status of session */ 158#define SE_SHUTDOWN 0x1 /* session won't be restarted */ 159#define SE_PRESENT 0x2 /* session is in /etc/ttys */ 160#define SE_IFEXISTS 0x4 /* session defined as "onifexists" */ 161#define SE_IFCONSOLE 0x8 /* session defined as "onifconsole" */ 162 int se_nspace; /* spacing count */ 163 char *se_device; /* filename of port */ 164 char *se_getty; /* what to run on that port */ 165 char *se_getty_argv_space; /* pre-parsed argument array space */ 166 char **se_getty_argv; /* pre-parsed argument array */ 167 char *se_window; /* window system (started only once) */ 168 char *se_window_argv_space; /* pre-parsed argument array space */ 169 char **se_window_argv; /* pre-parsed argument array */ 170 char *se_type; /* default terminal type */ 171 struct init_session *se_prev; 172 struct init_session *se_next; 173} session_t; 174 175static void free_session(session_t *); 176static session_t *new_session(session_t *, struct ttyent *); 177static session_t *sessions; 178 179static char **construct_argv(char *); 180static void start_window_system(session_t *); 181static void collect_child(pid_t); 182static pid_t start_getty(session_t *); 183static void transition_handler(int); 184static void alrm_handler(int); 185static void setsecuritylevel(int); 186static int getsecuritylevel(void); 187static int setupargv(session_t *, struct ttyent *); 188#ifdef LOGIN_CAP 189static void setprocresources(const char *); 190#endif 191static int clang; 192 193static int start_session_db(void); 194static void add_session(session_t *); 195static void del_session(session_t *); 196static session_t *find_session(pid_t); 197static DB *session_db; 198 199/* 200 * The mother of all processes. 201 */ 202int 203main(int argc, char *argv[]) 204{ 205 state_t initial_transition = runcom; 206 char kenv_value[PATH_MAX]; 207 int c, error; 208 struct sigaction sa; 209 sigset_t mask; 210 211 /* Dispose of random users. */ 212 if (getuid() != 0) 213 errx(1, "%s", strerror(EPERM)); 214 215 /* System V users like to reexec init. */ 216 if (getpid() != 1) { 217#ifdef COMPAT_SYSV_INIT 218 /* So give them what they want */ 219 if (argc > 1) { 220 if (strlen(argv[1]) == 1) { 221 char runlevel = *argv[1]; 222 int sig; 223 224 switch (runlevel) { 225 case '0': /* halt + poweroff */ 226 sig = SIGUSR2; 227 break; 228 case '1': /* single-user */ 229 sig = SIGTERM; 230 break; 231 case '6': /* reboot */ 232 sig = SIGINT; 233 break; 234 case 'c': /* block further logins */ 235 sig = SIGTSTP; 236 break; 237 case 'q': /* rescan /etc/ttys */ 238 sig = SIGHUP; 239 break; 240 case 'r': /* remount root */ 241 sig = SIGEMT; 242 break; 243 default: 244 goto invalid; 245 } 246 kill(1, sig); 247 _exit(0); 248 } else 249invalid: 250 errx(1, "invalid run-level ``%s''", argv[1]); 251 } else 252#endif 253 errx(1, "already running"); 254 } 255 256 init_path_argv0 = strdup(argv[0]); 257 if (init_path_argv0 == NULL) 258 err(1, "strdup"); 259 260 /* 261 * Note that this does NOT open a file... 262 * Does 'init' deserve its own facility number? 263 */ 264 openlog("init", LOG_CONS, LOG_AUTH); 265 266 /* 267 * Create an initial session. 268 */ 269 if (setsid() < 0 && (errno != EPERM || getsid(0) != 1)) 270 warning("initial setsid() failed: %m"); 271 272 /* 273 * Establish an initial user so that programs running 274 * single user do not freak out and die (like passwd). 275 */ 276 if (setlogin("root") < 0) 277 warning("setlogin() failed: %m"); 278 279 /* 280 * This code assumes that we always get arguments through flags, 281 * never through bits set in some random machine register. 282 */ 283 while ((c = getopt(argc, argv, "dsfr")) != -1) 284 switch (c) { 285 case 'd': 286 devfs = 1; 287 break; 288 case 's': 289 initial_transition = single_user; 290 break; 291 case 'f': 292 runcom_mode = FASTBOOT; 293 break; 294 case 'r': 295 initial_transition = reroot_phase_two; 296 break; 297 default: 298 warning("unrecognized flag '-%c'", c); 299 break; 300 } 301 302 if (optind != argc) 303 warning("ignoring excess arguments"); 304 305 /* 306 * We catch or block signals rather than ignore them, 307 * so that they get reset on exec. 308 */ 309 handle(disaster, SIGABRT, SIGFPE, SIGILL, SIGSEGV, SIGBUS, SIGSYS, 310 SIGXCPU, SIGXFSZ, 0); 311 handle(transition_handler, SIGHUP, SIGINT, SIGEMT, SIGTERM, SIGTSTP, 312 SIGUSR1, SIGUSR2, SIGWINCH, 0); 313 handle(alrm_handler, SIGALRM, 0); 314 sigfillset(&mask); 315 delset(&mask, SIGABRT, SIGFPE, SIGILL, SIGSEGV, SIGBUS, SIGSYS, 316 SIGXCPU, SIGXFSZ, SIGHUP, SIGINT, SIGEMT, SIGTERM, SIGTSTP, 317 SIGALRM, SIGUSR1, SIGUSR2, SIGWINCH, 0); 318 sigprocmask(SIG_SETMASK, &mask, NULL); 319 sigemptyset(&sa.sa_mask); 320 sa.sa_flags = 0; 321 sa.sa_handler = SIG_IGN; 322 sigaction(SIGTTIN, &sa, NULL); 323 sigaction(SIGTTOU, &sa, NULL); 324 325 /* 326 * Paranoia. 327 */ 328 close(0); 329 close(1); 330 close(2); 331 332 if (kenv(KENV_GET, "init_exec", kenv_value, sizeof(kenv_value)) > 0) { 333 replace_init(kenv_value); 334 _exit(0); /* reboot */ 335 } 336 337 if (kenv(KENV_GET, "init_script", kenv_value, sizeof(kenv_value)) > 0) { 338 state_func_t next_transition; 339 340 if ((next_transition = run_script(kenv_value)) != NULL) 341 initial_transition = (state_t) next_transition; 342 } 343 344 if (kenv(KENV_GET, "init_chroot", kenv_value, sizeof(kenv_value)) > 0) { 345 if (chdir(kenv_value) != 0 || chroot(".") != 0) 346 warning("Can't chroot to %s: %m", kenv_value); 347 } 348 349 /* 350 * Additional check if devfs needs to be mounted: 351 * If "/" and "/dev" have the same device number, 352 * then it hasn't been mounted yet. 353 */ 354 if (!devfs) { 355 struct stat stst; 356 dev_t root_devno; 357 358 stat("/", &stst); 359 root_devno = stst.st_dev; 360 if (stat("/dev", &stst) != 0) 361 warning("Can't stat /dev: %m"); 362 else if (stst.st_dev == root_devno) 363 devfs++; 364 } 365 366 if (devfs) { 367 struct iovec iov[4]; 368 char *s; 369 int i; 370 371 char _fstype[] = "fstype"; 372 char _devfs[] = "devfs"; 373 char _fspath[] = "fspath"; 374 char _path_dev[]= _PATH_DEV; 375 376 iov[0].iov_base = _fstype; 377 iov[0].iov_len = sizeof(_fstype); 378 iov[1].iov_base = _devfs; 379 iov[1].iov_len = sizeof(_devfs); 380 iov[2].iov_base = _fspath; 381 iov[2].iov_len = sizeof(_fspath); 382 /* 383 * Try to avoid the trailing slash in _PATH_DEV. 384 * Be *very* defensive. 385 */ 386 s = strdup(_PATH_DEV); 387 if (s != NULL) { 388 i = strlen(s); 389 if (i > 0 && s[i - 1] == '/') 390 s[i - 1] = '\0'; 391 iov[3].iov_base = s; 392 iov[3].iov_len = strlen(s) + 1; 393 } else { 394 iov[3].iov_base = _path_dev; 395 iov[3].iov_len = sizeof(_path_dev); 396 } 397 nmount(iov, 4, 0); 398 if (s != NULL) 399 free(s); 400 } 401 402 if (initial_transition != reroot_phase_two) { 403 /* 404 * Unmount reroot leftovers. This runs after init(8) 405 * gets reexecuted after reroot_phase_two() is done. 406 */ 407 error = unmount(_PATH_REROOT, MNT_FORCE); 408 if (error != 0 && errno != EINVAL) 409 warning("Cannot unmount %s: %m", _PATH_REROOT); 410 } 411 412 /* 413 * Start the state machine. 414 */ 415 transition(initial_transition); 416 417 /* 418 * Should never reach here. 419 */ 420 return 1; 421} 422 423/* 424 * Associate a function with a signal handler. 425 */ 426static void 427handle(sig_t handler, ...) 428{ 429 int sig; 430 struct sigaction sa; 431 sigset_t mask_everything; 432 va_list ap; 433 va_start(ap, handler); 434 435 sa.sa_handler = handler; 436 sigfillset(&mask_everything); 437 438 while ((sig = va_arg(ap, int)) != 0) { 439 sa.sa_mask = mask_everything; 440 /* XXX SA_RESTART? */ 441 sa.sa_flags = sig == SIGCHLD ? SA_NOCLDSTOP : 0; 442 sigaction(sig, &sa, NULL); 443 } 444 va_end(ap); 445} 446 447/* 448 * Delete a set of signals from a mask. 449 */ 450static void 451delset(sigset_t *maskp, ...) 452{ 453 int sig; 454 va_list ap; 455 va_start(ap, maskp); 456 457 while ((sig = va_arg(ap, int)) != 0) 458 sigdelset(maskp, sig); 459 va_end(ap); 460} 461 462/* 463 * Log a message and sleep for a while (to give someone an opportunity 464 * to read it and to save log or hardcopy output if the problem is chronic). 465 * NB: should send a message to the session logger to avoid blocking. 466 */ 467static void 468stall(const char *message, ...) 469{ 470 va_list ap; 471 va_start(ap, message); 472 473 vsyslog(LOG_ALERT, message, ap); 474 va_end(ap); 475 sleep(STALL_TIMEOUT); 476} 477 478/* 479 * Like stall(), but doesn't sleep. 480 * If cpp had variadic macros, the two functions could be #defines for another. 481 * NB: should send a message to the session logger to avoid blocking. 482 */ 483static void 484warning(const char *message, ...) 485{ 486 va_list ap; 487 va_start(ap, message); 488 489 vsyslog(LOG_ALERT, message, ap); 490 va_end(ap); 491} 492 493/* 494 * Log an emergency message. 495 * NB: should send a message to the session logger to avoid blocking. 496 */ 497static void 498emergency(const char *message, ...) 499{ 500 va_list ap; 501 va_start(ap, message); 502 503 vsyslog(LOG_EMERG, message, ap); 504 va_end(ap); 505} 506 507/* 508 * Catch an unexpected signal. 509 */ 510static void 511disaster(int sig) 512{ 513 514 emergency("fatal signal: %s", 515 (unsigned)sig < NSIG ? sys_siglist[sig] : "unknown signal"); 516 517 sleep(STALL_TIMEOUT); 518 _exit(sig); /* reboot */ 519} 520 521/* 522 * Get the security level of the kernel. 523 */ 524static int 525getsecuritylevel(void) 526{ 527#ifdef KERN_SECURELVL 528 int name[2], curlevel; 529 size_t len; 530 531 name[0] = CTL_KERN; 532 name[1] = KERN_SECURELVL; 533 len = sizeof curlevel; 534 if (sysctl(name, 2, &curlevel, &len, NULL, 0) == -1) { 535 emergency("cannot get kernel security level: %s", 536 strerror(errno)); 537 return (-1); 538 } 539 return (curlevel); 540#else 541 return (-1); 542#endif 543} 544 545/* 546 * Set the security level of the kernel. 547 */ 548static void 549setsecuritylevel(int newlevel) 550{ 551#ifdef KERN_SECURELVL 552 int name[2], curlevel; 553 554 curlevel = getsecuritylevel(); 555 if (newlevel == curlevel) 556 return; 557 name[0] = CTL_KERN; 558 name[1] = KERN_SECURELVL; 559 if (sysctl(name, 2, NULL, NULL, &newlevel, sizeof newlevel) == -1) { 560 emergency( 561 "cannot change kernel security level from %d to %d: %s", 562 curlevel, newlevel, strerror(errno)); 563 return; 564 } 565#ifdef SECURE 566 warning("kernel security level changed from %d to %d", 567 curlevel, newlevel); 568#endif 569#endif 570} 571 572/* 573 * Change states in the finite state machine. 574 * The initial state is passed as an argument. 575 */ 576static void 577transition(state_t s) 578{ 579 580 current_state = s; 581 for (;;) 582 current_state = (state_t) (*current_state)(); 583} 584 585/* 586 * Start a session and allocate a controlling terminal. 587 * Only called by children of init after forking. 588 */ 589static void 590open_console(void) 591{ 592 int fd; 593 594 /* 595 * Try to open /dev/console. Open the device with O_NONBLOCK to 596 * prevent potential blocking on a carrier. 597 */ 598 revoke(_PATH_CONSOLE); 599 if ((fd = open(_PATH_CONSOLE, O_RDWR | O_NONBLOCK)) != -1) { 600 (void)fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) & ~O_NONBLOCK); 601 if (login_tty(fd) == 0) 602 return; 603 close(fd); 604 } 605 606 /* No luck. Log output to file if possible. */ 607 if ((fd = open(_PATH_DEVNULL, O_RDWR)) == -1) { 608 stall("cannot open null device."); 609 _exit(1); 610 } 611 if (fd != STDIN_FILENO) { 612 dup2(fd, STDIN_FILENO); 613 close(fd); 614 } 615 fd = open(_PATH_INITLOG, O_WRONLY | O_APPEND | O_CREAT, 0644); 616 if (fd == -1) 617 dup2(STDIN_FILENO, STDOUT_FILENO); 618 else if (fd != STDOUT_FILENO) { 619 dup2(fd, STDOUT_FILENO); 620 close(fd); 621 } 622 dup2(STDOUT_FILENO, STDERR_FILENO); 623} 624 625static const char * 626get_shell(void) 627{ 628 static char kenv_value[PATH_MAX]; 629 630 if (kenv(KENV_GET, "init_shell", kenv_value, sizeof(kenv_value)) > 0) 631 return kenv_value; 632 else 633 return _PATH_BSHELL; 634} 635 636static void 637write_stderr(const char *message) 638{ 639 640 write(STDERR_FILENO, message, strlen(message)); 641} 642 643static int 644read_file(const char *path, void **bufp, size_t *bufsizep) 645{ 646 struct stat sb; 647 size_t bufsize; 648 void *buf; 649 ssize_t nbytes; 650 int error, fd; 651 652 fd = open(path, O_RDONLY); 653 if (fd < 0) { 654 emergency("%s: %s", path, strerror(errno)); 655 return (-1); 656 } 657 658 error = fstat(fd, &sb); 659 if (error != 0) { 660 emergency("fstat: %s", strerror(errno)); 661 close(fd); 662 return (error); 663 } 664 665 bufsize = sb.st_size; 666 buf = malloc(bufsize); 667 if (buf == NULL) { 668 emergency("malloc: %s", strerror(errno)); 669 close(fd); 670 return (error); 671 } 672 673 nbytes = read(fd, buf, bufsize); 674 if (nbytes != (ssize_t)bufsize) { 675 emergency("read: %s", strerror(errno)); 676 close(fd); 677 free(buf); 678 return (error); 679 } 680 681 error = close(fd); 682 if (error != 0) { 683 emergency("close: %s", strerror(errno)); 684 free(buf); 685 return (error); 686 } 687 688 *bufp = buf; 689 *bufsizep = bufsize; 690 691 return (0); 692} 693 694static int 695create_file(const char *path, const void *buf, size_t bufsize) 696{ 697 ssize_t nbytes; 698 int error, fd; 699 700 fd = open(path, O_WRONLY | O_CREAT | O_EXCL, 0700); 701 if (fd < 0) { 702 emergency("%s: %s", path, strerror(errno)); 703 return (-1); 704 } 705 706 nbytes = write(fd, buf, bufsize); 707 if (nbytes != (ssize_t)bufsize) { 708 emergency("write: %s", strerror(errno)); 709 close(fd); 710 return (-1); 711 } 712 713 error = close(fd); 714 if (error != 0) { 715 emergency("close: %s", strerror(errno)); 716 return (-1); 717 } 718 719 return (0); 720} 721 722static int 723mount_tmpfs(const char *fspath) 724{ 725 struct iovec *iov; 726 char errmsg[255]; 727 int error, iovlen; 728 729 iov = NULL; 730 iovlen = 0; 731 memset(errmsg, 0, sizeof(errmsg)); 732 build_iovec(&iov, &iovlen, "fstype", 733 __DECONST(void *, "tmpfs"), (size_t)-1); 734 build_iovec(&iov, &iovlen, "fspath", 735 __DECONST(void *, fspath), (size_t)-1); 736 build_iovec(&iov, &iovlen, "errmsg", 737 errmsg, sizeof(errmsg)); 738 739 error = nmount(iov, iovlen, 0); 740 if (error != 0) { 741 if (*errmsg != '\0') { 742 emergency("cannot mount tmpfs on %s: %s: %s", 743 fspath, errmsg, strerror(errno)); 744 } else { 745 emergency("cannot mount tmpfs on %s: %s", 746 fspath, strerror(errno)); 747 } 748 return (error); 749 } 750 return (0); 751} 752 753static state_func_t 754reroot(void) 755{ 756 void *buf; 757 size_t bufsize; 758 int error; 759 760 buf = NULL; 761 bufsize = 0; 762 763 revoke_ttys(); 764 runshutdown(); 765 766 /* 767 * Make sure nobody can interfere with our scheme. 768 * Ignore ESRCH, which can apparently happen when 769 * there are no processes to kill. 770 */ 771 error = kill(-1, SIGKILL); 772 if (error != 0 && errno != ESRCH) { 773 emergency("kill(2) failed: %s", strerror(errno)); 774 goto out; 775 } 776 777 /* 778 * Copy the init binary into tmpfs, so that we can unmount 779 * the old rootfs without committing suicide. 780 */ 781 error = read_file(init_path_argv0, &buf, &bufsize); 782 if (error != 0) 783 goto out; 784 error = mount_tmpfs(_PATH_REROOT); 785 if (error != 0) 786 goto out; 787 error = create_file(_PATH_REROOT_INIT, buf, bufsize); 788 if (error != 0) 789 goto out; 790 791 /* 792 * Execute the temporary init. 793 */ 794 execl(_PATH_REROOT_INIT, _PATH_REROOT_INIT, "-r", NULL); 795 emergency("cannot exec %s: %s", _PATH_REROOT_INIT, strerror(errno)); 796 797out: 798 emergency("reroot failed; going to single user mode"); 799 free(buf); 800 return (state_func_t) single_user; 801} 802 803static state_func_t 804reroot_phase_two(void) 805{ 806 char init_path[PATH_MAX], *path, *path_component; 807 size_t init_path_len; 808 int nbytes, error; 809 810 /* 811 * Ask the kernel to mount the new rootfs. 812 */ 813 error = reboot(RB_REROOT); 814 if (error != 0) { 815 emergency("RB_REBOOT failed: %s", strerror(errno)); 816 goto out; 817 } 818 819 /* 820 * Figure out where the destination init(8) binary is. Note that 821 * the path could be different than what we've started with. Use 822 * the value from kenv, if set, or the one from sysctl otherwise. 823 * The latter defaults to a hardcoded value, but can be overridden 824 * by a build time option. 825 */ 826 nbytes = kenv(KENV_GET, "init_path", init_path, sizeof(init_path)); 827 if (nbytes <= 0) { 828 init_path_len = sizeof(init_path); 829 error = sysctlbyname("kern.init_path", 830 init_path, &init_path_len, NULL, 0); 831 if (error != 0) { 832 emergency("failed to retrieve kern.init_path: %s", 833 strerror(errno)); 834 goto out; 835 } 836 } 837 838 /* 839 * Repeat the init search logic from sys/kern/init_path.c 840 */ 841 path_component = init_path; 842 while ((path = strsep(&path_component, ":")) != NULL) { 843 /* 844 * Execute init(8) from the new rootfs. 845 */ 846 execl(path, path, NULL); 847 } 848 emergency("cannot exec init from %s: %s", init_path, strerror(errno)); 849 850out: 851 emergency("reroot failed; going to single user mode"); 852 return (state_func_t) single_user; 853} 854 855/* 856 * Bring the system up single user. 857 */ 858static state_func_t 859single_user(void) 860{ 861 pid_t pid, wpid; 862 int status; 863 sigset_t mask; 864 const char *shell; 865 char *argv[2]; 866 struct timeval tv, tn; 867#ifdef SECURE 868 struct ttyent *typ; 869 struct passwd *pp; 870 static const char banner[] = 871 "Enter root password, or ^D to go multi-user\n"; 872 char *clear, *password; 873#endif 874#ifdef DEBUGSHELL 875 char altshell[128]; 876#endif 877 878 if (Reboot) { 879 /* Instead of going single user, let's reboot the machine */ 880 sync(); 881 if (reboot(howto) == -1) { 882 emergency("reboot(%#x) failed, %s", howto, 883 strerror(errno)); 884 _exit(1); /* panic and reboot */ 885 } 886 warning("reboot(%#x) returned", howto); 887 _exit(0); /* panic as well */ 888 } 889 890 shell = get_shell(); 891 892 if ((pid = fork()) == 0) { 893 /* 894 * Start the single user session. 895 */ 896 open_console(); 897 898#ifdef SECURE 899 /* 900 * Check the root password. 901 * We don't care if the console is 'on' by default; 902 * it's the only tty that can be 'off' and 'secure'. 903 */ 904 typ = getttynam("console"); 905 pp = getpwnam("root"); 906 if (typ && (typ->ty_status & TTY_SECURE) == 0 && 907 pp && *pp->pw_passwd) { 908 write_stderr(banner); 909 for (;;) { 910 clear = getpass("Password:"); 911 if (clear == NULL || *clear == '\0') 912 _exit(0); 913 password = crypt(clear, pp->pw_passwd); 914 explicit_bzero(clear, _PASSWORD_LEN); 915 if (password != NULL && 916 strcmp(password, pp->pw_passwd) == 0) 917 break; 918 warning("single-user login failed\n"); 919 } 920 } 921 endttyent(); 922 endpwent(); 923#endif /* SECURE */ 924 925#ifdef DEBUGSHELL 926 { 927 char *cp = altshell; 928 int num; 929 930#define SHREQUEST "Enter full pathname of shell or RETURN for " 931 write_stderr(SHREQUEST); 932 write_stderr(shell); 933 write_stderr(": "); 934 while ((num = read(STDIN_FILENO, cp, 1)) != -1 && 935 num != 0 && *cp != '\n' && cp < &altshell[127]) 936 cp++; 937 *cp = '\0'; 938 if (altshell[0] != '\0') 939 shell = altshell; 940 } 941#endif /* DEBUGSHELL */ 942 943 /* 944 * Unblock signals. 945 * We catch all the interesting ones, 946 * and those are reset to SIG_DFL on exec. 947 */ 948 sigemptyset(&mask); 949 sigprocmask(SIG_SETMASK, &mask, NULL); 950 951 /* 952 * Fire off a shell. 953 * If the default one doesn't work, try the Bourne shell. 954 */ 955 956 char name[] = "-sh"; 957 958 argv[0] = name; 959 argv[1] = NULL; 960 execv(shell, argv); 961 emergency("can't exec %s for single user: %m", shell); 962 execv(_PATH_BSHELL, argv); 963 emergency("can't exec %s for single user: %m", _PATH_BSHELL); 964 sleep(STALL_TIMEOUT); 965 _exit(1); 966 } 967 968 if (pid == -1) { 969 /* 970 * We are seriously hosed. Do our best. 971 */ 972 emergency("can't fork single-user shell, trying again"); 973 while (waitpid(-1, (int *) 0, WNOHANG) > 0) 974 continue; 975 return (state_func_t) single_user; 976 } 977 978 requested_transition = 0; 979 do { 980 if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1) 981 collect_child(wpid); 982 if (wpid == -1) { 983 if (errno == EINTR) 984 continue; 985 warning("wait for single-user shell failed: %m; restarting"); 986 return (state_func_t) single_user; 987 } 988 if (wpid == pid && WIFSTOPPED(status)) { 989 warning("init: shell stopped, restarting\n"); 990 kill(pid, SIGCONT); 991 wpid = -1; 992 } 993 } while (wpid != pid && !requested_transition); 994 995 if (requested_transition) 996 return (state_func_t) requested_transition; 997 998 if (!WIFEXITED(status)) { 999 if (WTERMSIG(status) == SIGKILL) { 1000 /* 1001 * reboot(8) killed shell? 1002 */ 1003 warning("single user shell terminated."); 1004 gettimeofday(&tv, NULL); 1005 tn = tv; 1006 tv.tv_sec += STALL_TIMEOUT; 1007 while (tv.tv_sec > tn.tv_sec || (tv.tv_sec == 1008 tn.tv_sec && tv.tv_usec > tn.tv_usec)) { 1009 sleep(1); 1010 gettimeofday(&tn, NULL); 1011 } 1012 _exit(0); 1013 } else { 1014 warning("single user shell terminated, restarting"); 1015 return (state_func_t) single_user; 1016 } 1017 } 1018 1019 runcom_mode = FASTBOOT; 1020 return (state_func_t) runcom; 1021} 1022 1023/* 1024 * Run the system startup script. 1025 */ 1026static state_func_t 1027runcom(void) 1028{ 1029 state_func_t next_transition; 1030 1031 if ((next_transition = run_script(_PATH_RUNCOM)) != NULL) 1032 return next_transition; 1033 1034 runcom_mode = AUTOBOOT; /* the default */ 1035 return (state_func_t) read_ttys; 1036} 1037 1038static void 1039execute_script(char *argv[]) 1040{ 1041 struct sigaction sa; 1042 const char *shell, *script; 1043 int error; 1044 1045 bzero(&sa, sizeof(sa)); 1046 sigemptyset(&sa.sa_mask); 1047 sa.sa_handler = SIG_IGN; 1048 sigaction(SIGTSTP, &sa, NULL); 1049 sigaction(SIGHUP, &sa, NULL); 1050 1051 open_console(); 1052 1053 sigprocmask(SIG_SETMASK, &sa.sa_mask, NULL); 1054#ifdef LOGIN_CAP 1055 setprocresources(RESOURCE_RC); 1056#endif 1057 1058 /* 1059 * Try to directly execute the script first. If it 1060 * fails, try the old method of passing the script path 1061 * to sh(1). Don't complain if it fails because of 1062 * the missing execute bit. 1063 */ 1064 script = argv[1]; 1065 error = access(script, X_OK); 1066 if (error == 0) { 1067 execv(script, argv + 1); 1068 warning("can't exec %s: %m", script); 1069 } else if (errno != EACCES) { 1070 warning("can't access %s: %m", script); 1071 } 1072 1073 shell = get_shell(); 1074 execv(shell, argv); 1075 stall("can't exec %s for %s: %m", shell, script); 1076} 1077 1078/* 1079 * Execute binary, replacing init(8) as PID 1. 1080 */ 1081static void 1082replace_init(char *path) 1083{ 1084 char *argv[3]; 1085 char sh[] = "sh"; 1086 1087 argv[0] = sh; 1088 argv[1] = path; 1089 argv[2] = NULL; 1090 1091 execute_script(argv); 1092} 1093 1094/* 1095 * Run a shell script. 1096 * Returns 0 on success, otherwise the next transition to enter: 1097 * - single_user if fork/execv/waitpid failed, or if the script 1098 * terminated with a signal or exit code != 0. 1099 * - death_single if a SIGTERM was delivered to init(8). 1100 */ 1101static state_func_t 1102run_script(const char *script) 1103{ 1104 pid_t pid, wpid; 1105 int status; 1106 char *argv[4]; 1107 const char *shell; 1108 1109 shell = get_shell(); 1110 1111 if ((pid = fork()) == 0) { 1112 1113 char _sh[] = "sh"; 1114 char _autoboot[] = "autoboot"; 1115 1116 argv[0] = _sh; 1117 argv[1] = __DECONST(char *, script); 1118 argv[2] = runcom_mode == AUTOBOOT ? _autoboot : 0; 1119 argv[3] = 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 (wpid == -1) { 1142 if (requested_transition == death_single || 1143 requested_transition == reroot) 1144 return (state_func_t) requested_transition; 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: %s", strerror(errno)); 1191 if ((session_db = dbopen(NULL, O_RDWR, 0, DB_HASH, NULL)) == NULL) { 1192 emergency("session database open: %s", strerror(errno)); 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: %s", sp->se_process, strerror(errno)); 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: %s", sp->se_process, strerror(errno)); 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 1601/* 1602 * Catch a signal and request a state transition. 1603 */ 1604static void 1605transition_handler(int sig) 1606{ 1607 1608 switch (sig) { 1609 case SIGHUP: 1610 if (current_state == read_ttys || current_state == multi_user || 1611 current_state == clean_ttys || current_state == catatonia) 1612 requested_transition = clean_ttys; 1613 break; 1614 case SIGWINCH: 1615 case SIGUSR2: 1616 howto = sig == SIGUSR2 ? RB_POWEROFF : RB_POWERCYCLE; 1617 case SIGUSR1: 1618 howto |= RB_HALT; 1619 case SIGINT: 1620 Reboot = TRUE; 1621 case SIGTERM: 1622 if (current_state == read_ttys || current_state == multi_user || 1623 current_state == clean_ttys || current_state == catatonia) 1624 requested_transition = death; 1625 else 1626 requested_transition = death_single; 1627 break; 1628 case SIGTSTP: 1629 if (current_state == runcom || current_state == read_ttys || 1630 current_state == clean_ttys || 1631 current_state == multi_user || current_state == catatonia) 1632 requested_transition = catatonia; 1633 break; 1634 case SIGEMT: 1635 requested_transition = reroot; 1636 break; 1637 default: 1638 requested_transition = 0; 1639 break; 1640 } 1641} 1642 1643/* 1644 * Take the system multiuser. 1645 */ 1646static state_func_t 1647multi_user(void) 1648{ 1649 pid_t pid; 1650 session_t *sp; 1651 1652 requested_transition = 0; 1653 1654 /* 1655 * If the administrator has not set the security level to -1 1656 * to indicate that the kernel should not run multiuser in secure 1657 * mode, and the run script has not set a higher level of security 1658 * than level 1, then put the kernel into secure mode. 1659 */ 1660 if (getsecuritylevel() == 0) 1661 setsecuritylevel(1); 1662 1663 for (sp = sessions; sp; sp = sp->se_next) { 1664 if (sp->se_process) 1665 continue; 1666 if (session_has_no_tty(sp)) 1667 continue; 1668 if ((pid = start_getty(sp)) == -1) { 1669 /* serious trouble */ 1670 requested_transition = clean_ttys; 1671 break; 1672 } 1673 sp->se_process = pid; 1674 sp->se_started = time((time_t *) 0); 1675 add_session(sp); 1676 } 1677 1678 while (!requested_transition) 1679 if ((pid = waitpid(-1, (int *) 0, 0)) != -1) 1680 collect_child(pid); 1681 1682 return (state_func_t) requested_transition; 1683} 1684 1685/* 1686 * This is an (n*2)+(n^2) algorithm. We hope it isn't run often... 1687 */ 1688static state_func_t 1689clean_ttys(void) 1690{ 1691 session_t *sp, *sprev; 1692 struct ttyent *typ; 1693 int devlen; 1694 char *old_getty, *old_window, *old_type; 1695 1696 /* 1697 * mark all sessions for death, (!SE_PRESENT) 1698 * as we find or create new ones they'll be marked as keepers, 1699 * we'll later nuke all the ones not found in /etc/ttys 1700 */ 1701 for (sp = sessions; sp != NULL; sp = sp->se_next) 1702 sp->se_flags &= ~SE_PRESENT; 1703 1704 devlen = sizeof(_PATH_DEV) - 1; 1705 while ((typ = getttyent()) != NULL) { 1706 for (sprev = 0, sp = sessions; sp; sprev = sp, sp = sp->se_next) 1707 if (strcmp(typ->ty_name, sp->se_device + devlen) == 0) 1708 break; 1709 1710 if (sp) { 1711 /* we want this one to live */ 1712 sp->se_flags |= SE_PRESENT; 1713 if ((typ->ty_status & TTY_ON) == 0 || 1714 typ->ty_getty == 0) { 1715 sp->se_flags |= SE_SHUTDOWN; 1716 kill(sp->se_process, SIGHUP); 1717 continue; 1718 } 1719 sp->se_flags &= ~SE_SHUTDOWN; 1720 old_getty = sp->se_getty ? strdup(sp->se_getty) : 0; 1721 old_window = sp->se_window ? strdup(sp->se_window) : 0; 1722 old_type = sp->se_type ? strdup(sp->se_type) : 0; 1723 if (setupargv(sp, typ) == 0) { 1724 warning("can't parse getty for port %s", 1725 sp->se_device); 1726 sp->se_flags |= SE_SHUTDOWN; 1727 kill(sp->se_process, SIGHUP); 1728 } 1729 else if ( !old_getty 1730 || (!old_type && sp->se_type) 1731 || (old_type && !sp->se_type) 1732 || (!old_window && sp->se_window) 1733 || (old_window && !sp->se_window) 1734 || (strcmp(old_getty, sp->se_getty) != 0) 1735 || (old_window && strcmp(old_window, sp->se_window) != 0) 1736 || (old_type && strcmp(old_type, sp->se_type) != 0) 1737 ) { 1738 /* Don't set SE_SHUTDOWN here */ 1739 sp->se_nspace = 0; 1740 sp->se_started = 0; 1741 kill(sp->se_process, SIGHUP); 1742 } 1743 if (old_getty) 1744 free(old_getty); 1745 if (old_window) 1746 free(old_window); 1747 if (old_type) 1748 free(old_type); 1749 continue; 1750 } 1751 1752 new_session(sprev, typ); 1753 } 1754 1755 endttyent(); 1756 1757 /* 1758 * sweep through and kill all deleted sessions 1759 * ones who's /etc/ttys line was deleted (SE_PRESENT unset) 1760 */ 1761 for (sp = sessions; sp != NULL; sp = sp->se_next) { 1762 if ((sp->se_flags & SE_PRESENT) == 0) { 1763 sp->se_flags |= SE_SHUTDOWN; 1764 kill(sp->se_process, SIGHUP); 1765 } 1766 } 1767 1768 return (state_func_t) multi_user; 1769} 1770 1771/* 1772 * Block further logins. 1773 */ 1774static state_func_t 1775catatonia(void) 1776{ 1777 session_t *sp; 1778 1779 for (sp = sessions; sp; sp = sp->se_next) 1780 sp->se_flags |= SE_SHUTDOWN; 1781 1782 return (state_func_t) multi_user; 1783} 1784 1785/* 1786 * Note SIGALRM. 1787 */ 1788static void 1789alrm_handler(int sig) 1790{ 1791 1792 (void)sig; 1793 clang = 1; 1794} 1795 1796/* 1797 * Bring the system down to single user. 1798 */ 1799static state_func_t 1800death(void) 1801{ 1802 int block, blocked; 1803 size_t len; 1804 1805 /* Temporarily block suspend. */ 1806 len = sizeof(blocked); 1807 block = 1; 1808 if (sysctlbyname("kern.suspend_blocked", &blocked, &len, 1809 &block, sizeof(block)) == -1) 1810 blocked = 0; 1811 1812 /* 1813 * Also revoke the TTY here. Because runshutdown() may reopen 1814 * the TTY whose getty we're killing here, there is no guarantee 1815 * runshutdown() will perform the initial open() call, causing 1816 * the terminal attributes to be misconfigured. 1817 */ 1818 revoke_ttys(); 1819 1820 /* Try to run the rc.shutdown script within a period of time */ 1821 runshutdown(); 1822 1823 /* Unblock suspend if we blocked it. */ 1824 if (!blocked) 1825 sysctlbyname("kern.suspend_blocked", NULL, NULL, 1826 &blocked, sizeof(blocked)); 1827 1828 return (state_func_t) death_single; 1829} 1830 1831/* 1832 * Do what is necessary to reinitialize single user mode or reboot 1833 * from an incomplete state. 1834 */ 1835static state_func_t 1836death_single(void) 1837{ 1838 int i; 1839 pid_t pid; 1840 static const int death_sigs[2] = { SIGTERM, SIGKILL }; 1841 1842 revoke(_PATH_CONSOLE); 1843 1844 for (i = 0; i < 2; ++i) { 1845 if (kill(-1, death_sigs[i]) == -1 && errno == ESRCH) 1846 return (state_func_t) single_user; 1847 1848 clang = 0; 1849 alarm(DEATH_WATCH); 1850 do 1851 if ((pid = waitpid(-1, (int *)0, 0)) != -1) 1852 collect_child(pid); 1853 while (clang == 0 && errno != ECHILD); 1854 1855 if (errno == ECHILD) 1856 return (state_func_t) single_user; 1857 } 1858 1859 warning("some processes would not die; ps axl advised"); 1860 1861 return (state_func_t) single_user; 1862} 1863 1864static void 1865revoke_ttys(void) 1866{ 1867 session_t *sp; 1868 1869 for (sp = sessions; sp; sp = sp->se_next) { 1870 sp->se_flags |= SE_SHUTDOWN; 1871 kill(sp->se_process, SIGHUP); 1872 revoke(sp->se_device); 1873 } 1874} 1875 1876/* 1877 * Run the system shutdown script. 1878 * 1879 * Exit codes: XXX I should document more 1880 * -2 shutdown script terminated abnormally 1881 * -1 fatal error - can't run script 1882 * 0 good. 1883 * >0 some error (exit code) 1884 */ 1885static int 1886runshutdown(void) 1887{ 1888 pid_t pid, wpid; 1889 int status; 1890 int shutdowntimeout; 1891 size_t len; 1892 char *argv[4]; 1893 struct stat sb; 1894 1895 /* 1896 * rc.shutdown is optional, so to prevent any unnecessary 1897 * complaints from the shell we simply don't run it if the 1898 * file does not exist. If the stat() here fails for other 1899 * reasons, we'll let the shell complain. 1900 */ 1901 if (stat(_PATH_RUNDOWN, &sb) == -1 && errno == ENOENT) 1902 return 0; 1903 1904 if ((pid = fork()) == 0) { 1905 char _sh[] = "sh"; 1906 char _reboot[] = "reboot"; 1907 char _single[] = "single"; 1908 char _path_rundown[] = _PATH_RUNDOWN; 1909 1910 argv[0] = _sh; 1911 argv[1] = _path_rundown; 1912 argv[2] = Reboot ? _reboot : _single; 1913 argv[3] = NULL; 1914 1915 execute_script(argv); 1916 _exit(1); /* force single user mode */ 1917 } 1918 1919 if (pid == -1) { 1920 emergency("can't fork for %s: %m", _PATH_RUNDOWN); 1921 while (waitpid(-1, (int *) 0, WNOHANG) > 0) 1922 continue; 1923 sleep(STALL_TIMEOUT); 1924 return -1; 1925 } 1926 1927 len = sizeof(shutdowntimeout); 1928 if (sysctlbyname("kern.init_shutdown_timeout", &shutdowntimeout, &len, 1929 NULL, 0) == -1 || shutdowntimeout < 2) 1930 shutdowntimeout = DEATH_SCRIPT; 1931 alarm(shutdowntimeout); 1932 clang = 0; 1933 /* 1934 * Copied from single_user(). This is a bit paranoid. 1935 * Use the same ALRM handler. 1936 */ 1937 do { 1938 if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1) 1939 collect_child(wpid); 1940 if (clang == 1) { 1941 /* we were waiting for the sub-shell */ 1942 kill(wpid, SIGTERM); 1943 warning("timeout expired for %s: %m; going to " 1944 "single user mode", _PATH_RUNDOWN); 1945 return -1; 1946 } 1947 if (wpid == -1) { 1948 if (errno == EINTR) 1949 continue; 1950 warning("wait for %s failed: %m; going to " 1951 "single user mode", _PATH_RUNDOWN); 1952 return -1; 1953 } 1954 if (wpid == pid && WIFSTOPPED(status)) { 1955 warning("init: %s stopped, restarting\n", 1956 _PATH_RUNDOWN); 1957 kill(pid, SIGCONT); 1958 wpid = -1; 1959 } 1960 } while (wpid != pid && !clang); 1961 1962 /* Turn off the alarm */ 1963 alarm(0); 1964 1965 if (WIFSIGNALED(status) && WTERMSIG(status) == SIGTERM && 1966 requested_transition == catatonia) { 1967 /* 1968 * /etc/rc.shutdown executed /sbin/reboot; 1969 * wait for the end quietly 1970 */ 1971 sigset_t s; 1972 1973 sigfillset(&s); 1974 for (;;) 1975 sigsuspend(&s); 1976 } 1977 1978 if (!WIFEXITED(status)) { 1979 warning("%s terminated abnormally, going to " 1980 "single user mode", _PATH_RUNDOWN); 1981 return -2; 1982 } 1983 1984 if ((status = WEXITSTATUS(status)) != 0) 1985 warning("%s returned status %d", _PATH_RUNDOWN, status); 1986 1987 return status; 1988} 1989 1990static char * 1991strk(char *p) 1992{ 1993 static char *t; 1994 char *q; 1995 int c; 1996 1997 if (p) 1998 t = p; 1999 if (!t) 2000 return 0; 2001 2002 c = *t; 2003 while (c == ' ' || c == '\t' ) 2004 c = *++t; 2005 if (!c) { 2006 t = 0; 2007 return 0; 2008 } 2009 q = t; 2010 if (c == '\'') { 2011 c = *++t; 2012 q = t; 2013 while (c && c != '\'') 2014 c = *++t; 2015 if (!c) /* unterminated string */ 2016 q = t = 0; 2017 else 2018 *t++ = 0; 2019 } else { 2020 while (c && c != ' ' && c != '\t' ) 2021 c = *++t; 2022 *t++ = 0; 2023 if (!c) 2024 t = 0; 2025 } 2026 return q; 2027} 2028 2029#ifdef LOGIN_CAP 2030static void 2031setprocresources(const char *cname) 2032{ 2033 login_cap_t *lc; 2034 if ((lc = login_getclassbyname(cname, NULL)) != NULL) { 2035 setusercontext(lc, (struct passwd*)NULL, 0, 2036 LOGIN_SETENV | 2037 LOGIN_SETPRIORITY | LOGIN_SETRESOURCES | 2038 LOGIN_SETLOGINCLASS | LOGIN_SETCPUMASK); 2039 login_close(lc); 2040 } 2041} 2042#endif 2043