diff --git a/sbin/init/init.8 b/sbin/init/init.8 index d852c32ef487..9475b1cce48f 100644 --- a/sbin/init/init.8 +++ b/sbin/init/init.8 @@ -1,458 +1,469 @@ .\" Copyright (c) 1980, 1991, 1993 .\" The Regents of the University of California. All rights reserved. .\" .\" This code is derived from software contributed to Berkeley by .\" Donn Seeley at Berkeley Software Design, Inc. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" 3. Neither the name of the University nor the names of its contributors .\" may be used to endorse or promote products derived from this software .\" without specific prior written permission. .\" .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" .\" @(#)init.8 8.3 (Berkeley) 4/18/94 .\" $FreeBSD$ .\" -.Dd August 6, 2019 +.Dd July 22, 2021 .Dt INIT 8 .Os .Sh NAME .Nm init .Nd process control initialization .Sh SYNOPSIS .Nm .Nm .Oo .Cm 0 | 1 | 6 | .Cm c | q .Oc .Sh DESCRIPTION The .Nm utility is the last stage of the boot process. It normally runs the automatic reboot sequence as described in .Xr rc 8 , and if this succeeds, begins multi-user operation. If the reboot scripts fail, .Nm commences single-user operation by giving the super-user a shell on the console. The .Nm utility may be passed parameters from the boot program to prevent the system from going multi-user and to instead execute a single-user shell without starting the normal daemons. The system is then quiescent for maintenance work and may later be made to go to multi-user by exiting the single-user shell (with ^D). This causes .Nm to run the .Pa /etc/rc start up command file in fastboot mode (skipping disk checks). .Pp If the .Em console entry in the .Xr ttys 5 file is marked .Dq insecure , then .Nm will require that the super-user password be entered before the system will start a single-user shell. The password check is skipped if the .Em console is marked as .Dq secure . Note that the password check does not protect from variables such as .Va init_script being set from the .Xr loader 8 command line; see the .Sx SECURITY section of .Xr loader 8 . .Pp If the system security level (see .Xr security 7 ) is initially nonzero, then .Nm leaves it unchanged. Otherwise, .Nm raises the level to 1 before going multi-user for the first time. Since the level cannot be reduced, it will be at least 1 for subsequent operation, even on return to single-user. If a level higher than 1 is desired while running multi-user, it can be set before going multi-user, e.g., by the startup script .Xr rc 8 , using .Xr sysctl 8 to set the .Va kern.securelevel variable to the required security level. .Pp If .Nm is run in a jail, the security level of the .Dq host system will not be affected. Part of the information set up in the kernel to support a jail is a per-jail security level. This allows running a higher security level inside of a jail than that of the host system. See .Xr jail 8 for more information about jails. .Pp In multi-user operation, .Nm maintains processes for the terminal ports found in the file .Xr ttys 5 . The .Nm utility reads this file and executes the command found in the second field, unless the first field refers to a device in .Pa /dev which is not configured. The first field is supplied as the final argument to the command. This command is usually .Xr getty 8 ; .Nm getty opens and initializes the tty line and executes the .Xr login 1 program. The .Nm login program, when a valid user logs in, executes a shell for that user. When this shell dies, either because the user logged out or an abnormal termination occurred (a signal), the cycle is restarted by executing a new .Nm getty for the line. .Pp The .Nm utility can also be used to keep arbitrary daemons running, automatically restarting them if they die. In this case, the first field in the .Xr ttys 5 file must not reference the path to a configured device node and will be passed to the daemon as the final argument on its command line. This is similar to the facility offered in the .At V .Pa /etc/inittab . .Pp Line status (on, off, secure, getty, or window information) may be changed in the .Xr ttys 5 file without a reboot by sending the signal .Dv SIGHUP to .Nm with the command .Dq Li "kill -HUP 1" . On receipt of this signal, .Nm re-reads the .Xr ttys 5 file. When a line is turned off in .Xr ttys 5 , .Nm will send a SIGHUP signal to the controlling process for the session associated with the line. For any lines that were previously turned off in the .Xr ttys 5 file and are now on, .Nm executes the command specified in the second field. If the command or window field for a line is changed, the change takes effect at the end of the current login session (e.g., the next time .Nm starts a process on the line). If a line is commented out or deleted from .Xr ttys 5 , .Nm will not do anything at all to that line. .Pp The .Nm utility will terminate multi-user operations and resume single-user mode if sent a terminate .Pq Dv TERM signal, for example, .Dq Li "kill \-TERM 1" . If there are processes outstanding that are deadlocked (because of hardware or software failure), .Nm will not wait for them all to die (which might take forever), but will time out after 30 seconds and print a warning message. .Pp The .Nm utility will cease creating new processes and allow the system to slowly die away, if it is sent a terminal stop .Pq Dv TSTP signal, i.e.\& .Dq Li "kill \-TSTP 1" . A later hangup will resume full multi-user operations, or a terminate will start a single-user shell. This hook is used by .Xr reboot 8 and .Xr halt 8 . .Pp The .Nm utility will terminate all possible processes (again, it will not wait for deadlocked processes) and reboot the machine if sent the interrupt .Pq Dv INT signal, i.e.\& .Dq Li "kill \-INT 1". This is useful for shutting the machine down cleanly from inside the kernel or from X when the machine appears to be hung. .Pp The .Nm utility will do the same, except it will halt the machine if sent the user defined signal 1 .Pq Dv USR1 , or will halt and turn the power off (if hardware permits) if sent the user defined signal 2 .Pq Dv USR2 . .Pp When shutting down the machine, .Nm will try to run the .Pa /etc/rc.shutdown script. This script can be used to cleanly terminate specific programs such as .Nm innd (the InterNetNews server). If this script does not terminate within 120 seconds, .Nm will terminate it. The timeout can be configured via the .Xr sysctl 8 variable .Va kern.init_shutdown_timeout . .Pp .Nm init passes .Dq Li single as the argument to the shutdown script if return to single-user mode is requested. Otherwise, .Dq Li reboot argument is used. .Pp +After all user processes have been terminated, +.Nm +will try to run the +.Pa /etc/rc.final +script. +This script can be used to finally prepare and unmount filesystems that may have +been needed during shutdown, for instance. +.Pp The role of .Nm is so critical that if it dies, the system will reboot itself automatically. If, at bootstrap time, the .Nm process cannot be located, the system will panic with the message .Dq "panic: init died (signal %d, exit %d)" . .Pp If run as a user process as shown in the second synopsis line, .Nm will emulate .At V behavior, i.e., super-user can specify the desired .Em run-level on a command line, and .Nm will signal the original (PID 1) .Nm as follows: .Bl -column Run-level SIGTERM .It Sy "Run-level Signal Action" .It Cm 0 Ta Dv SIGUSR1 Ta "Halt" .It Cm 0 Ta Dv SIGUSR2 Ta "Halt and turn the power off" .It Cm 0 Ta Dv SIGWINCH Ta "Halt and turn the power off and then back on" .It Cm 1 Ta Dv SIGTERM Ta "Go to single-user mode" .It Cm 6 Ta Dv SIGINT Ta "Reboot the machine" .It Cm c Ta Dv SIGTSTP Ta "Block further logins" .It Cm q Ta Dv SIGHUP Ta Rescan the .Xr ttys 5 file .El .Sh KERNEL ENVIRONMENT VARIABLES The following .Xr kenv 2 variables are available as .Xr loader 8 tunables: .Bl -tag -width indent .It Va init_chroot If set to a valid directory in the root file system, it causes .Nm to perform a .Xr chroot 2 operation on that directory, making it the new root directory. That happens before entering single-user mode or multi-user mode (but after executing the .Va init_script if enabled). This functionality has generally been eclipsed by rerooting. See .Xr reboot 8 .Fl r for details. .It Va init_exec If set to a valid file name in the root file system, instructs .Nm to directly execute that file as the very first action, replacing .Nm as PID 1. .It Va init_script If set to a valid file name in the root file system, instructs .Nm to run that script as the very first action, before doing anything else. Signal handling and exit code interpretation is similar to running the .Pa /etc/rc script. In particular, single-user operation is enforced if the script terminates with a non-zero exit code, or if a SIGTERM is delivered to the .Nm process (PID 1). This functionality has generally been eclipsed by rerooting. See .Xr reboot 8 .Fl r for details. .It Va init_shell Defines the shell binary to be used for executing the various shell scripts. The default is .Dq Li /bin/sh . It is used for running the .Va init_exec or .Va init_script if set, as well as for the -.Pa /etc/rc +.Pa /etc/rc , +.Pa /etc/rc.shutdown , and -.Pa /etc/rc.shutdown +.Pa /etc/rc.final scripts. The value of the corresponding .Xr kenv 2 variable is evaluated every time .Nm calls a shell script, so it can be changed later on using the .Xr kenv 1 utility. In particular, if a non-default shell is used for running an .Va init_script , it might be desirable to have that script reset the value of .Va init_shell back to the default, so that the .Pa /etc/rc script is executed with the standard shell .Pa /bin/sh . .Sh FILES .Bl -tag -width /var/log/init.log -compact .It Pa /dev/console system console device .It Pa /dev/tty* terminal ports found in .Xr ttys 5 .It Pa /etc/ttys the terminal initialization information file .It Pa /etc/rc system startup commands .It Pa /etc/rc.shutdown system shutdown commands +.It Pa /etc/rc.final +system shutdown commands (after process termination) .It Pa /var/log/init.log log of .Xr rc 8 output if the system console device is not available .El .Sh DIAGNOSTICS .Bl -diag .It "getty repeating too quickly on port %s, sleeping." A process being started to service a line is exiting quickly each time it is started. This is often caused by a ringing or noisy terminal line. .Bf -emphasis Init will sleep for 30 seconds, then continue trying to start the process. .Ef .It "some processes would not die; ps axl advised." A process is hung and could not be killed when the system was shutting down. This condition is usually caused by a process that is stuck in a device driver because of a persistent device error condition. .El .Sh SEE ALSO .Xr kill 1 , .Xr login 1 , .Xr sh 1 , .Xr ttys 5 , .Xr security 7 , .Xr getty 8 , .Xr halt 8 , .Xr jail 8 , .Xr rc 8 , .Xr reboot 8 , .Xr shutdown 8 , .Xr sysctl 8 .Sh HISTORY An .Nm utility appeared in .At v1 . .Sh CAVEATS Systems without .Xr sysctl 8 behave as though they have security level \-1. .Pp Setting the security level above 1 too early in the boot sequence can prevent .Xr fsck 8 from repairing inconsistent file systems. The preferred location to set the security level is at the end of .Pa /etc/rc after all multi-user startup actions are complete. diff --git a/sbin/init/init.c b/sbin/init/init.c index 943db9f26bd3..230c141bd351 100644 --- a/sbin/init/init.c +++ b/sbin/init/init.c @@ -1,2041 +1,2092 @@ /*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 1991, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * Donn Seeley at Berkeley Software Design, Inc. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #ifndef lint static const char copyright[] = "@(#) Copyright (c) 1991, 1993\n\ The Regents of the University of California. All rights reserved.\n"; #endif /* not lint */ #ifndef lint #if 0 static char sccsid[] = "@(#)init.c 8.1 (Berkeley) 7/15/93"; #endif static const char rcsid[] = "$FreeBSD$"; #endif /* not lint */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef SECURE #include #endif #ifdef LOGIN_CAP #include #endif #include "mntopts.h" #include "pathnames.h" /* * Sleep times; used to prevent thrashing. */ #define GETTY_SPACING 5 /* N secs minimum getty spacing */ #define GETTY_SLEEP 30 /* sleep N secs after spacing problem */ #define GETTY_NSPACE 3 /* max. spacing count to bring reaction */ #define WINDOW_WAIT 3 /* wait N secs after starting window */ #define STALL_TIMEOUT 30 /* wait N secs after warning */ #define DEATH_WATCH 10 /* wait N secs for procs to die */ #define DEATH_SCRIPT 120 /* wait for 2min for /etc/rc.shutdown */ #define RESOURCE_RC "daemon" #define RESOURCE_WINDOW "default" #define RESOURCE_GETTY "default" static void handle(sig_t, ...); static void delset(sigset_t *, ...); static void stall(const char *, ...) __printflike(1, 2); static void warning(const char *, ...) __printflike(1, 2); static void emergency(const char *, ...) __printflike(1, 2); static void disaster(int); static void revoke_ttys(void); static int runshutdown(void); static char *strk(char *); +static void runfinal(void); /* * We really need a recursive typedef... * The following at least guarantees that the return type of (*state_t)() * is sufficiently wide to hold a function pointer. */ typedef long (*state_func_t)(void); typedef state_func_t (*state_t)(void); static state_func_t single_user(void); static state_func_t runcom(void); static state_func_t read_ttys(void); static state_func_t multi_user(void); static state_func_t clean_ttys(void); static state_func_t catatonia(void); static state_func_t death(void); static state_func_t death_single(void); static state_func_t reroot(void); static state_func_t reroot_phase_two(void); static state_func_t run_script(const char *); static enum { AUTOBOOT, FASTBOOT } runcom_mode = AUTOBOOT; #define FALSE 0 #define TRUE 1 static int Reboot = FALSE; static int howto = RB_AUTOBOOT; static int devfs; static char *init_path_argv0; static void transition(state_t); static state_t requested_transition; static state_t current_state = death_single; static void execute_script(char *argv[]); static void open_console(void); static const char *get_shell(void); static void replace_init(char *path); static void write_stderr(const char *message); typedef struct init_session { pid_t se_process; /* controlling process */ time_t se_started; /* used to avoid thrashing */ int se_flags; /* status of session */ #define SE_SHUTDOWN 0x1 /* session won't be restarted */ #define SE_PRESENT 0x2 /* session is in /etc/ttys */ #define SE_IFEXISTS 0x4 /* session defined as "onifexists" */ #define SE_IFCONSOLE 0x8 /* session defined as "onifconsole" */ int se_nspace; /* spacing count */ char *se_device; /* filename of port */ char *se_getty; /* what to run on that port */ char *se_getty_argv_space; /* pre-parsed argument array space */ char **se_getty_argv; /* pre-parsed argument array */ char *se_window; /* window system (started only once) */ char *se_window_argv_space; /* pre-parsed argument array space */ char **se_window_argv; /* pre-parsed argument array */ char *se_type; /* default terminal type */ struct init_session *se_prev; struct init_session *se_next; } session_t; static void free_session(session_t *); static session_t *new_session(session_t *, struct ttyent *); static session_t *sessions; static char **construct_argv(char *); static void start_window_system(session_t *); static void collect_child(pid_t); static pid_t start_getty(session_t *); static void transition_handler(int); static void alrm_handler(int); static void setsecuritylevel(int); static int getsecuritylevel(void); static int setupargv(session_t *, struct ttyent *); #ifdef LOGIN_CAP static void setprocresources(const char *); #endif static int clang; static int start_session_db(void); static void add_session(session_t *); static void del_session(session_t *); static session_t *find_session(pid_t); static DB *session_db; /* * The mother of all processes. */ int main(int argc, char *argv[]) { state_t initial_transition = runcom; char kenv_value[PATH_MAX]; int c, error; struct sigaction sa; sigset_t mask; /* Dispose of random users. */ if (getuid() != 0) errx(1, "%s", strerror(EPERM)); /* System V users like to reexec init. */ if (getpid() != 1) { #ifdef COMPAT_SYSV_INIT /* So give them what they want */ if (argc > 1) { if (strlen(argv[1]) == 1) { char runlevel = *argv[1]; int sig; switch (runlevel) { case '0': /* halt + poweroff */ sig = SIGUSR2; break; case '1': /* single-user */ sig = SIGTERM; break; case '6': /* reboot */ sig = SIGINT; break; case 'c': /* block further logins */ sig = SIGTSTP; break; case 'q': /* rescan /etc/ttys */ sig = SIGHUP; break; case 'r': /* remount root */ sig = SIGEMT; break; default: goto invalid; } kill(1, sig); _exit(0); } else invalid: errx(1, "invalid run-level ``%s''", argv[1]); } else #endif errx(1, "already running"); } init_path_argv0 = strdup(argv[0]); if (init_path_argv0 == NULL) err(1, "strdup"); /* * Note that this does NOT open a file... * Does 'init' deserve its own facility number? */ openlog("init", LOG_CONS, LOG_AUTH); /* * Create an initial session. */ if (setsid() < 0 && (errno != EPERM || getsid(0) != 1)) warning("initial setsid() failed: %m"); /* * Establish an initial user so that programs running * single user do not freak out and die (like passwd). */ if (setlogin("root") < 0) warning("setlogin() failed: %m"); /* * This code assumes that we always get arguments through flags, * never through bits set in some random machine register. */ while ((c = getopt(argc, argv, "dsfr")) != -1) switch (c) { case 'd': devfs = 1; break; case 's': initial_transition = single_user; break; case 'f': runcom_mode = FASTBOOT; break; case 'r': initial_transition = reroot_phase_two; break; default: warning("unrecognized flag '-%c'", c); break; } if (optind != argc) warning("ignoring excess arguments"); /* * We catch or block signals rather than ignore them, * so that they get reset on exec. */ handle(disaster, SIGABRT, SIGFPE, SIGILL, SIGSEGV, SIGBUS, SIGSYS, SIGXCPU, SIGXFSZ, 0); handle(transition_handler, SIGHUP, SIGINT, SIGEMT, SIGTERM, SIGTSTP, SIGUSR1, SIGUSR2, SIGWINCH, 0); handle(alrm_handler, SIGALRM, 0); sigfillset(&mask); delset(&mask, SIGABRT, SIGFPE, SIGILL, SIGSEGV, SIGBUS, SIGSYS, SIGXCPU, SIGXFSZ, SIGHUP, SIGINT, SIGEMT, SIGTERM, SIGTSTP, SIGALRM, SIGUSR1, SIGUSR2, SIGWINCH, 0); sigprocmask(SIG_SETMASK, &mask, NULL); sigemptyset(&sa.sa_mask); sa.sa_flags = 0; sa.sa_handler = SIG_IGN; sigaction(SIGTTIN, &sa, NULL); sigaction(SIGTTOU, &sa, NULL); /* * Paranoia. */ close(0); close(1); close(2); if (kenv(KENV_GET, "init_exec", kenv_value, sizeof(kenv_value)) > 0) { replace_init(kenv_value); _exit(0); /* reboot */ } if (kenv(KENV_GET, "init_script", kenv_value, sizeof(kenv_value)) > 0) { state_func_t next_transition; if ((next_transition = run_script(kenv_value)) != NULL) initial_transition = (state_t) next_transition; } if (kenv(KENV_GET, "init_chroot", kenv_value, sizeof(kenv_value)) > 0) { if (chdir(kenv_value) != 0 || chroot(".") != 0) warning("Can't chroot to %s: %m", kenv_value); } /* * Additional check if devfs needs to be mounted: * If "/" and "/dev" have the same device number, * then it hasn't been mounted yet. */ if (!devfs) { struct stat stst; dev_t root_devno; stat("/", &stst); root_devno = stst.st_dev; if (stat("/dev", &stst) != 0) warning("Can't stat /dev: %m"); else if (stst.st_dev == root_devno) devfs++; } if (devfs) { struct iovec iov[4]; char *s; int i; char _fstype[] = "fstype"; char _devfs[] = "devfs"; char _fspath[] = "fspath"; char _path_dev[]= _PATH_DEV; iov[0].iov_base = _fstype; iov[0].iov_len = sizeof(_fstype); iov[1].iov_base = _devfs; iov[1].iov_len = sizeof(_devfs); iov[2].iov_base = _fspath; iov[2].iov_len = sizeof(_fspath); /* * Try to avoid the trailing slash in _PATH_DEV. * Be *very* defensive. */ s = strdup(_PATH_DEV); if (s != NULL) { i = strlen(s); if (i > 0 && s[i - 1] == '/') s[i - 1] = '\0'; iov[3].iov_base = s; iov[3].iov_len = strlen(s) + 1; } else { iov[3].iov_base = _path_dev; iov[3].iov_len = sizeof(_path_dev); } nmount(iov, 4, 0); if (s != NULL) free(s); } if (initial_transition != reroot_phase_two) { /* * Unmount reroot leftovers. This runs after init(8) * gets reexecuted after reroot_phase_two() is done. */ error = unmount(_PATH_REROOT, MNT_FORCE); if (error != 0 && errno != EINVAL) warning("Cannot unmount %s: %m", _PATH_REROOT); } /* * Start the state machine. */ transition(initial_transition); /* * Should never reach here. */ return 1; } /* * Associate a function with a signal handler. */ static void handle(sig_t handler, ...) { int sig; struct sigaction sa; sigset_t mask_everything; va_list ap; va_start(ap, handler); sa.sa_handler = handler; sigfillset(&mask_everything); while ((sig = va_arg(ap, int)) != 0) { sa.sa_mask = mask_everything; /* XXX SA_RESTART? */ sa.sa_flags = sig == SIGCHLD ? SA_NOCLDSTOP : 0; sigaction(sig, &sa, NULL); } va_end(ap); } /* * Delete a set of signals from a mask. */ static void delset(sigset_t *maskp, ...) { int sig; va_list ap; va_start(ap, maskp); while ((sig = va_arg(ap, int)) != 0) sigdelset(maskp, sig); va_end(ap); } /* * Log a message and sleep for a while (to give someone an opportunity * to read it and to save log or hardcopy output if the problem is chronic). * NB: should send a message to the session logger to avoid blocking. */ static void stall(const char *message, ...) { va_list ap; va_start(ap, message); vsyslog(LOG_ALERT, message, ap); va_end(ap); sleep(STALL_TIMEOUT); } /* * Like stall(), but doesn't sleep. * If cpp had variadic macros, the two functions could be #defines for another. * NB: should send a message to the session logger to avoid blocking. */ static void warning(const char *message, ...) { va_list ap; va_start(ap, message); vsyslog(LOG_ALERT, message, ap); va_end(ap); } /* * Log an emergency message. * NB: should send a message to the session logger to avoid blocking. */ static void emergency(const char *message, ...) { va_list ap; va_start(ap, message); vsyslog(LOG_EMERG, message, ap); va_end(ap); } /* * Catch an unexpected signal. */ static void disaster(int sig) { emergency("fatal signal: %s", (unsigned)sig < NSIG ? sys_siglist[sig] : "unknown signal"); sleep(STALL_TIMEOUT); _exit(sig); /* reboot */ } /* * Get the security level of the kernel. */ static int getsecuritylevel(void) { #ifdef KERN_SECURELVL int name[2], curlevel; size_t len; name[0] = CTL_KERN; name[1] = KERN_SECURELVL; len = sizeof curlevel; if (sysctl(name, 2, &curlevel, &len, NULL, 0) == -1) { emergency("cannot get kernel security level: %m"); return (-1); } return (curlevel); #else return (-1); #endif } /* * Set the security level of the kernel. */ static void setsecuritylevel(int newlevel) { #ifdef KERN_SECURELVL int name[2], curlevel; curlevel = getsecuritylevel(); if (newlevel == curlevel) return; name[0] = CTL_KERN; name[1] = KERN_SECURELVL; if (sysctl(name, 2, NULL, NULL, &newlevel, sizeof newlevel) == -1) { emergency( "cannot change kernel security level from %d to %d: %m", curlevel, newlevel); return; } #ifdef SECURE warning("kernel security level changed from %d to %d", curlevel, newlevel); #endif #endif } /* * Change states in the finite state machine. * The initial state is passed as an argument. */ static void transition(state_t s) { current_state = s; for (;;) current_state = (state_t) (*current_state)(); } /* * Start a session and allocate a controlling terminal. * Only called by children of init after forking. */ static void open_console(void) { int fd; /* * Try to open /dev/console. Open the device with O_NONBLOCK to * prevent potential blocking on a carrier. */ revoke(_PATH_CONSOLE); if ((fd = open(_PATH_CONSOLE, O_RDWR | O_NONBLOCK)) != -1) { (void)fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) & ~O_NONBLOCK); if (login_tty(fd) == 0) return; close(fd); } /* No luck. Log output to file if possible. */ if ((fd = open(_PATH_DEVNULL, O_RDWR)) == -1) { stall("cannot open null device."); _exit(1); } if (fd != STDIN_FILENO) { dup2(fd, STDIN_FILENO); close(fd); } fd = open(_PATH_INITLOG, O_WRONLY | O_APPEND | O_CREAT, 0644); if (fd == -1) dup2(STDIN_FILENO, STDOUT_FILENO); else if (fd != STDOUT_FILENO) { dup2(fd, STDOUT_FILENO); close(fd); } dup2(STDOUT_FILENO, STDERR_FILENO); } static const char * get_shell(void) { static char kenv_value[PATH_MAX]; if (kenv(KENV_GET, "init_shell", kenv_value, sizeof(kenv_value)) > 0) return kenv_value; else return _PATH_BSHELL; } static void write_stderr(const char *message) { write(STDERR_FILENO, message, strlen(message)); } static int read_file(const char *path, void **bufp, size_t *bufsizep) { struct stat sb; size_t bufsize; void *buf; ssize_t nbytes; int error, fd; fd = open(path, O_RDONLY); if (fd < 0) { emergency("%s: %m", path); return (-1); } error = fstat(fd, &sb); if (error != 0) { emergency("fstat: %m"); close(fd); return (error); } bufsize = sb.st_size; buf = malloc(bufsize); if (buf == NULL) { emergency("malloc: %m"); close(fd); return (error); } nbytes = read(fd, buf, bufsize); if (nbytes != (ssize_t)bufsize) { emergency("read: %m"); close(fd); free(buf); return (error); } error = close(fd); if (error != 0) { emergency("close: %m"); free(buf); return (error); } *bufp = buf; *bufsizep = bufsize; return (0); } static int create_file(const char *path, const void *buf, size_t bufsize) { ssize_t nbytes; int error, fd; fd = open(path, O_WRONLY | O_CREAT | O_EXCL, 0700); if (fd < 0) { emergency("%s: %m", path); return (-1); } nbytes = write(fd, buf, bufsize); if (nbytes != (ssize_t)bufsize) { emergency("write: %m"); close(fd); return (-1); } error = close(fd); if (error != 0) { emergency("close: %m"); return (-1); } return (0); } static int mount_tmpfs(const char *fspath) { struct iovec *iov; char errmsg[255]; int error, iovlen; iov = NULL; iovlen = 0; memset(errmsg, 0, sizeof(errmsg)); build_iovec(&iov, &iovlen, "fstype", __DECONST(void *, "tmpfs"), (size_t)-1); build_iovec(&iov, &iovlen, "fspath", __DECONST(void *, fspath), (size_t)-1); build_iovec(&iov, &iovlen, "errmsg", errmsg, sizeof(errmsg)); error = nmount(iov, iovlen, 0); if (error != 0) { if (*errmsg != '\0') { emergency("cannot mount tmpfs on %s: %s: %m", fspath, errmsg); } else { emergency("cannot mount tmpfs on %s: %m", fspath); } return (error); } return (0); } static state_func_t reroot(void) { void *buf; size_t bufsize; int error; buf = NULL; bufsize = 0; revoke_ttys(); runshutdown(); /* * Make sure nobody can interfere with our scheme. * Ignore ESRCH, which can apparently happen when * there are no processes to kill. */ error = kill(-1, SIGKILL); if (error != 0 && errno != ESRCH) { emergency("kill(2) failed: %m"); goto out; } /* * Copy the init binary into tmpfs, so that we can unmount * the old rootfs without committing suicide. */ error = read_file(init_path_argv0, &buf, &bufsize); if (error != 0) goto out; error = mount_tmpfs(_PATH_REROOT); if (error != 0) goto out; error = create_file(_PATH_REROOT_INIT, buf, bufsize); if (error != 0) goto out; /* * Execute the temporary init. */ execl(_PATH_REROOT_INIT, _PATH_REROOT_INIT, "-r", NULL); emergency("cannot exec %s: %m", _PATH_REROOT_INIT); out: emergency("reroot failed; going to single user mode"); free(buf); return (state_func_t) single_user; } static state_func_t reroot_phase_two(void) { char init_path[PATH_MAX], *path, *path_component; size_t init_path_len; int nbytes, error; /* * Ask the kernel to mount the new rootfs. */ error = reboot(RB_REROOT); if (error != 0) { emergency("RB_REBOOT failed: %m"); goto out; } /* * Figure out where the destination init(8) binary is. Note that * the path could be different than what we've started with. Use * the value from kenv, if set, or the one from sysctl otherwise. * The latter defaults to a hardcoded value, but can be overridden * by a build time option. */ nbytes = kenv(KENV_GET, "init_path", init_path, sizeof(init_path)); if (nbytes <= 0) { init_path_len = sizeof(init_path); error = sysctlbyname("kern.init_path", init_path, &init_path_len, NULL, 0); if (error != 0) { emergency("failed to retrieve kern.init_path: %m"); goto out; } } /* * Repeat the init search logic from sys/kern/init_path.c */ path_component = init_path; while ((path = strsep(&path_component, ":")) != NULL) { /* * Execute init(8) from the new rootfs. */ execl(path, path, NULL); } emergency("cannot exec init from %s: %m", init_path); out: emergency("reroot failed; going to single user mode"); return (state_func_t) single_user; } /* * Bring the system up single user. */ static state_func_t single_user(void) { pid_t pid, wpid; int status; sigset_t mask; const char *shell; char *argv[2]; struct timeval tv, tn; #ifdef SECURE struct ttyent *typ; struct passwd *pp; static const char banner[] = "Enter root password, or ^D to go multi-user\n"; char *clear, *password; #endif #ifdef DEBUGSHELL char altshell[128]; #endif if (Reboot) { /* Instead of going single user, let's reboot the machine */ sync(); + /* Run scripts after all processes have been terminated. */ + runfinal(); if (reboot(howto) == -1) { emergency("reboot(%#x) failed, %m", howto); _exit(1); /* panic and reboot */ } warning("reboot(%#x) returned", howto); _exit(0); /* panic as well */ } shell = get_shell(); if ((pid = fork()) == 0) { /* * Start the single user session. */ open_console(); #ifdef SECURE /* * Check the root password. * We don't care if the console is 'on' by default; * it's the only tty that can be 'off' and 'secure'. */ typ = getttynam("console"); pp = getpwnam("root"); if (typ && (typ->ty_status & TTY_SECURE) == 0 && pp && *pp->pw_passwd) { write_stderr(banner); for (;;) { clear = getpass("Password:"); if (clear == NULL || *clear == '\0') _exit(0); password = crypt(clear, pp->pw_passwd); explicit_bzero(clear, _PASSWORD_LEN); if (password != NULL && strcmp(password, pp->pw_passwd) == 0) break; warning("single-user login failed\n"); } } endttyent(); endpwent(); #endif /* SECURE */ #ifdef DEBUGSHELL { char *cp = altshell; int num; #define SHREQUEST "Enter full pathname of shell or RETURN for " write_stderr(SHREQUEST); write_stderr(shell); write_stderr(": "); while ((num = read(STDIN_FILENO, cp, 1)) != -1 && num != 0 && *cp != '\n' && cp < &altshell[127]) cp++; *cp = '\0'; if (altshell[0] != '\0') shell = altshell; } #endif /* DEBUGSHELL */ /* * Unblock signals. * We catch all the interesting ones, * and those are reset to SIG_DFL on exec. */ sigemptyset(&mask); sigprocmask(SIG_SETMASK, &mask, NULL); /* * Fire off a shell. * If the default one doesn't work, try the Bourne shell. */ char name[] = "-sh"; argv[0] = name; argv[1] = NULL; execv(shell, argv); emergency("can't exec %s for single user: %m", shell); execv(_PATH_BSHELL, argv); emergency("can't exec %s for single user: %m", _PATH_BSHELL); sleep(STALL_TIMEOUT); _exit(1); } if (pid == -1) { /* * We are seriously hosed. Do our best. */ emergency("can't fork single-user shell, trying again"); while (waitpid(-1, (int *) 0, WNOHANG) > 0) continue; return (state_func_t) single_user; } requested_transition = 0; do { if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1) collect_child(wpid); if (wpid == -1) { if (errno == EINTR) continue; warning("wait for single-user shell failed: %m; restarting"); return (state_func_t) single_user; } if (wpid == pid && WIFSTOPPED(status)) { warning("init: shell stopped, restarting\n"); kill(pid, SIGCONT); wpid = -1; } } while (wpid != pid && !requested_transition); if (requested_transition) return (state_func_t) requested_transition; if (!WIFEXITED(status)) { if (WTERMSIG(status) == SIGKILL) { /* * reboot(8) killed shell? */ warning("single user shell terminated."); gettimeofday(&tv, NULL); tn = tv; tv.tv_sec += STALL_TIMEOUT; while (tv.tv_sec > tn.tv_sec || (tv.tv_sec == tn.tv_sec && tv.tv_usec > tn.tv_usec)) { sleep(1); gettimeofday(&tn, NULL); } _exit(0); } else { warning("single user shell terminated, restarting"); return (state_func_t) single_user; } } runcom_mode = FASTBOOT; return (state_func_t) runcom; } /* * Run the system startup script. */ static state_func_t runcom(void) { state_func_t next_transition; if ((next_transition = run_script(_PATH_RUNCOM)) != NULL) return next_transition; runcom_mode = AUTOBOOT; /* the default */ return (state_func_t) read_ttys; } static void execute_script(char *argv[]) { struct sigaction sa; const char *shell, *script; int error; bzero(&sa, sizeof(sa)); sigemptyset(&sa.sa_mask); sa.sa_handler = SIG_IGN; sigaction(SIGTSTP, &sa, NULL); sigaction(SIGHUP, &sa, NULL); open_console(); sigprocmask(SIG_SETMASK, &sa.sa_mask, NULL); #ifdef LOGIN_CAP setprocresources(RESOURCE_RC); #endif /* * Try to directly execute the script first. If it * fails, try the old method of passing the script path * to sh(1). Don't complain if it fails because of * the missing execute bit. */ script = argv[1]; error = access(script, X_OK); if (error == 0) { execv(script, argv + 1); warning("can't directly exec %s: %m", script); } else if (errno != EACCES) { warning("can't access %s: %m", script); } shell = get_shell(); execv(shell, argv); stall("can't exec %s for %s: %m", shell, script); } /* * Execute binary, replacing init(8) as PID 1. */ static void replace_init(char *path) { char *argv[3]; char sh[] = "sh"; argv[0] = sh; argv[1] = path; argv[2] = NULL; execute_script(argv); } /* * Run a shell script. * Returns 0 on success, otherwise the next transition to enter: * - single_user if fork/execv/waitpid failed, or if the script * terminated with a signal or exit code != 0. * - death_single if a SIGTERM was delivered to init(8). */ static state_func_t run_script(const char *script) { pid_t pid, wpid; int status; char *argv[4]; const char *shell; shell = get_shell(); if ((pid = fork()) == 0) { char _sh[] = "sh"; char _autoboot[] = "autoboot"; argv[0] = _sh; argv[1] = __DECONST(char *, script); argv[2] = runcom_mode == AUTOBOOT ? _autoboot : 0; argv[3] = NULL; execute_script(argv); sleep(STALL_TIMEOUT); _exit(1); /* force single user mode */ } if (pid == -1) { emergency("can't fork for %s on %s: %m", shell, script); while (waitpid(-1, (int *) 0, WNOHANG) > 0) continue; sleep(STALL_TIMEOUT); return (state_func_t) single_user; } /* * Copied from single_user(). This is a bit paranoid. */ requested_transition = 0; do { if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1) collect_child(wpid); if (wpid == -1) { if (requested_transition == death_single || requested_transition == reroot) return (state_func_t) requested_transition; if (errno == EINTR) continue; warning("wait for %s on %s failed: %m; going to " "single user mode", shell, script); return (state_func_t) single_user; } if (wpid == pid && WIFSTOPPED(status)) { warning("init: %s on %s stopped, restarting\n", shell, script); kill(pid, SIGCONT); wpid = -1; } } while (wpid != pid); if (WIFSIGNALED(status) && WTERMSIG(status) == SIGTERM && requested_transition == catatonia) { /* /etc/rc executed /sbin/reboot; wait for the end quietly */ sigset_t s; sigfillset(&s); for (;;) sigsuspend(&s); } if (!WIFEXITED(status)) { warning("%s on %s terminated abnormally, going to single " "user mode", shell, script); return (state_func_t) single_user; } if (WEXITSTATUS(status)) return (state_func_t) single_user; return (state_func_t) 0; } /* * Open the session database. * * NB: We could pass in the size here; is it necessary? */ static int start_session_db(void) { if (session_db && (*session_db->close)(session_db)) emergency("session database close: %m"); if ((session_db = dbopen(NULL, O_RDWR, 0, DB_HASH, NULL)) == NULL) { emergency("session database open: %m"); return (1); } return (0); } /* * Add a new login session. */ static void add_session(session_t *sp) { DBT key; DBT data; key.data = &sp->se_process; key.size = sizeof sp->se_process; data.data = &sp; data.size = sizeof sp; if ((*session_db->put)(session_db, &key, &data, 0)) emergency("insert %d: %m", sp->se_process); } /* * Delete an old login session. */ static void del_session(session_t *sp) { DBT key; key.data = &sp->se_process; key.size = sizeof sp->se_process; if ((*session_db->del)(session_db, &key, 0)) emergency("delete %d: %m", sp->se_process); } /* * Look up a login session by pid. */ static session_t * find_session(pid_t pid) { DBT key; DBT data; session_t *ret; key.data = &pid; key.size = sizeof pid; if ((*session_db->get)(session_db, &key, &data, 0) != 0) return 0; bcopy(data.data, (char *)&ret, sizeof(ret)); return ret; } /* * Construct an argument vector from a command line. */ static char ** construct_argv(char *command) { int argc = 0; char **argv = (char **) malloc(((strlen(command) + 1) / 2 + 1) * sizeof (char *)); if ((argv[argc++] = strk(command)) == NULL) { free(argv); return (NULL); } while ((argv[argc++] = strk((char *) 0)) != NULL) continue; return argv; } /* * Deallocate a session descriptor. */ static void free_session(session_t *sp) { free(sp->se_device); if (sp->se_getty) { free(sp->se_getty); free(sp->se_getty_argv_space); free(sp->se_getty_argv); } if (sp->se_window) { free(sp->se_window); free(sp->se_window_argv_space); free(sp->se_window_argv); } if (sp->se_type) free(sp->se_type); free(sp); } /* * Allocate a new session descriptor. * Mark it SE_PRESENT. */ static session_t * new_session(session_t *sprev, struct ttyent *typ) { session_t *sp; if ((typ->ty_status & TTY_ON) == 0 || typ->ty_name == 0 || typ->ty_getty == 0) return 0; sp = (session_t *) calloc(1, sizeof (session_t)); sp->se_flags |= SE_PRESENT; if ((typ->ty_status & TTY_IFEXISTS) != 0) sp->se_flags |= SE_IFEXISTS; if ((typ->ty_status & TTY_IFCONSOLE) != 0) sp->se_flags |= SE_IFCONSOLE; if (asprintf(&sp->se_device, "%s%s", _PATH_DEV, typ->ty_name) < 0) err(1, "asprintf"); if (setupargv(sp, typ) == 0) { free_session(sp); return (0); } sp->se_next = 0; if (sprev == NULL) { sessions = sp; sp->se_prev = 0; } else { sprev->se_next = sp; sp->se_prev = sprev; } return sp; } /* * Calculate getty and if useful window argv vectors. */ static int setupargv(session_t *sp, struct ttyent *typ) { if (sp->se_getty) { free(sp->se_getty); free(sp->se_getty_argv_space); free(sp->se_getty_argv); } if (asprintf(&sp->se_getty, "%s %s", typ->ty_getty, typ->ty_name) < 0) err(1, "asprintf"); sp->se_getty_argv_space = strdup(sp->se_getty); sp->se_getty_argv = construct_argv(sp->se_getty_argv_space); if (sp->se_getty_argv == NULL) { warning("can't parse getty for port %s", sp->se_device); free(sp->se_getty); free(sp->se_getty_argv_space); sp->se_getty = sp->se_getty_argv_space = 0; return (0); } if (sp->se_window) { free(sp->se_window); free(sp->se_window_argv_space); free(sp->se_window_argv); } sp->se_window = sp->se_window_argv_space = 0; sp->se_window_argv = 0; if (typ->ty_window) { sp->se_window = strdup(typ->ty_window); sp->se_window_argv_space = strdup(sp->se_window); sp->se_window_argv = construct_argv(sp->se_window_argv_space); if (sp->se_window_argv == NULL) { warning("can't parse window for port %s", sp->se_device); free(sp->se_window_argv_space); free(sp->se_window); sp->se_window = sp->se_window_argv_space = 0; return (0); } } if (sp->se_type) free(sp->se_type); sp->se_type = typ->ty_type ? strdup(typ->ty_type) : 0; return (1); } /* * Walk the list of ttys and create sessions for each active line. */ static state_func_t read_ttys(void) { session_t *sp, *snext; struct ttyent *typ; /* * Destroy any previous session state. * There shouldn't be any, but just in case... */ for (sp = sessions; sp; sp = snext) { snext = sp->se_next; free_session(sp); } sessions = 0; if (start_session_db()) return (state_func_t) single_user; /* * Allocate a session entry for each active port. * Note that sp starts at 0. */ while ((typ = getttyent()) != NULL) if ((snext = new_session(sp, typ)) != NULL) sp = snext; endttyent(); return (state_func_t) multi_user; } /* * Start a window system running. */ static void start_window_system(session_t *sp) { pid_t pid; sigset_t mask; char term[64], *env[2]; int status; if ((pid = fork()) == -1) { emergency("can't fork for window system on port %s: %m", sp->se_device); /* hope that getty fails and we can try again */ return; } if (pid) { waitpid(-1, &status, 0); return; } /* reparent window process to the init to not make a zombie on exit */ if ((pid = fork()) == -1) { emergency("can't fork for window system on port %s: %m", sp->se_device); _exit(1); } if (pid) _exit(0); sigemptyset(&mask); sigprocmask(SIG_SETMASK, &mask, NULL); if (setsid() < 0) emergency("setsid failed (window) %m"); #ifdef LOGIN_CAP setprocresources(RESOURCE_WINDOW); #endif if (sp->se_type) { /* Don't use malloc after fork */ strcpy(term, "TERM="); strlcat(term, sp->se_type, sizeof(term)); env[0] = term; env[1] = NULL; } else env[0] = NULL; execve(sp->se_window_argv[0], sp->se_window_argv, env); stall("can't exec window system '%s' for port %s: %m", sp->se_window_argv[0], sp->se_device); _exit(1); } /* * Start a login session running. */ static pid_t start_getty(session_t *sp) { pid_t pid; sigset_t mask; time_t current_time = time((time_t *) 0); int too_quick = 0; char term[64], *env[2]; if (current_time >= sp->se_started && current_time - sp->se_started < GETTY_SPACING) { if (++sp->se_nspace > GETTY_NSPACE) { sp->se_nspace = 0; too_quick = 1; } } else sp->se_nspace = 0; /* * fork(), not vfork() -- we can't afford to block. */ if ((pid = fork()) == -1) { emergency("can't fork for getty on port %s: %m", sp->se_device); return -1; } if (pid) return pid; if (too_quick) { warning("getty repeating too quickly on port %s, sleeping %d secs", sp->se_device, GETTY_SLEEP); sleep((unsigned) GETTY_SLEEP); } if (sp->se_window) { start_window_system(sp); sleep(WINDOW_WAIT); } sigemptyset(&mask); sigprocmask(SIG_SETMASK, &mask, NULL); #ifdef LOGIN_CAP setprocresources(RESOURCE_GETTY); #endif if (sp->se_type) { /* Don't use malloc after fork */ strcpy(term, "TERM="); strlcat(term, sp->se_type, sizeof(term)); env[0] = term; env[1] = NULL; } else env[0] = NULL; execve(sp->se_getty_argv[0], sp->se_getty_argv, env); stall("can't exec getty '%s' for port %s: %m", sp->se_getty_argv[0], sp->se_device); _exit(1); } /* * Return 1 if the session is defined as "onifexists" * or "onifconsole" and the device node does not exist. */ static int session_has_no_tty(session_t *sp) { int fd; if ((sp->se_flags & SE_IFEXISTS) == 0 && (sp->se_flags & SE_IFCONSOLE) == 0) return (0); fd = open(sp->se_device, O_RDONLY | O_NONBLOCK, 0); if (fd < 0) { if (errno == ENOENT) return (1); return (0); } close(fd); return (0); } /* * Collect exit status for a child. * If an exiting login, start a new login running. */ static void collect_child(pid_t pid) { session_t *sp, *sprev, *snext; if (! sessions) return; if (! (sp = find_session(pid))) return; del_session(sp); sp->se_process = 0; if (sp->se_flags & SE_SHUTDOWN || session_has_no_tty(sp)) { if ((sprev = sp->se_prev) != NULL) sprev->se_next = sp->se_next; else sessions = sp->se_next; if ((snext = sp->se_next) != NULL) snext->se_prev = sp->se_prev; free_session(sp); return; } if ((pid = start_getty(sp)) == -1) { /* serious trouble */ requested_transition = clean_ttys; return; } sp->se_process = pid; sp->se_started = time((time_t *) 0); add_session(sp); } /* * Catch a signal and request a state transition. */ static void transition_handler(int sig) { switch (sig) { case SIGHUP: if (current_state == read_ttys || current_state == multi_user || current_state == clean_ttys || current_state == catatonia) requested_transition = clean_ttys; break; case SIGUSR2: howto = RB_POWEROFF; case SIGUSR1: howto |= RB_HALT; case SIGWINCH: case SIGINT: if (sig == SIGWINCH) howto |= RB_POWERCYCLE; Reboot = TRUE; case SIGTERM: if (current_state == read_ttys || current_state == multi_user || current_state == clean_ttys || current_state == catatonia) requested_transition = death; else requested_transition = death_single; break; case SIGTSTP: if (current_state == runcom || current_state == read_ttys || current_state == clean_ttys || current_state == multi_user || current_state == catatonia) requested_transition = catatonia; break; case SIGEMT: requested_transition = reroot; break; default: requested_transition = 0; break; } } /* * Take the system multiuser. */ static state_func_t multi_user(void) { pid_t pid; session_t *sp; requested_transition = 0; /* * If the administrator has not set the security level to -1 * to indicate that the kernel should not run multiuser in secure * mode, and the run script has not set a higher level of security * than level 1, then put the kernel into secure mode. */ if (getsecuritylevel() == 0) setsecuritylevel(1); for (sp = sessions; sp; sp = sp->se_next) { if (sp->se_process) continue; if (session_has_no_tty(sp)) continue; if ((pid = start_getty(sp)) == -1) { /* serious trouble */ requested_transition = clean_ttys; break; } sp->se_process = pid; sp->se_started = time((time_t *) 0); add_session(sp); } while (!requested_transition) if ((pid = waitpid(-1, (int *) 0, 0)) != -1) collect_child(pid); return (state_func_t) requested_transition; } /* * This is an (n*2)+(n^2) algorithm. We hope it isn't run often... */ static state_func_t clean_ttys(void) { session_t *sp, *sprev; struct ttyent *typ; int devlen; char *old_getty, *old_window, *old_type; /* * mark all sessions for death, (!SE_PRESENT) * as we find or create new ones they'll be marked as keepers, * we'll later nuke all the ones not found in /etc/ttys */ for (sp = sessions; sp != NULL; sp = sp->se_next) sp->se_flags &= ~SE_PRESENT; devlen = sizeof(_PATH_DEV) - 1; while ((typ = getttyent()) != NULL) { for (sprev = 0, sp = sessions; sp; sprev = sp, sp = sp->se_next) if (strcmp(typ->ty_name, sp->se_device + devlen) == 0) break; if (sp) { /* we want this one to live */ sp->se_flags |= SE_PRESENT; if ((typ->ty_status & TTY_ON) == 0 || typ->ty_getty == 0) { sp->se_flags |= SE_SHUTDOWN; kill(sp->se_process, SIGHUP); continue; } sp->se_flags &= ~SE_SHUTDOWN; old_getty = sp->se_getty ? strdup(sp->se_getty) : 0; old_window = sp->se_window ? strdup(sp->se_window) : 0; old_type = sp->se_type ? strdup(sp->se_type) : 0; if (setupargv(sp, typ) == 0) { warning("can't parse getty for port %s", sp->se_device); sp->se_flags |= SE_SHUTDOWN; kill(sp->se_process, SIGHUP); } else if ( !old_getty || (!old_type && sp->se_type) || (old_type && !sp->se_type) || (!old_window && sp->se_window) || (old_window && !sp->se_window) || (strcmp(old_getty, sp->se_getty) != 0) || (old_window && strcmp(old_window, sp->se_window) != 0) || (old_type && strcmp(old_type, sp->se_type) != 0) ) { /* Don't set SE_SHUTDOWN here */ sp->se_nspace = 0; sp->se_started = 0; kill(sp->se_process, SIGHUP); } if (old_getty) free(old_getty); if (old_window) free(old_window); if (old_type) free(old_type); continue; } new_session(sprev, typ); } endttyent(); /* * sweep through and kill all deleted sessions * ones who's /etc/ttys line was deleted (SE_PRESENT unset) */ for (sp = sessions; sp != NULL; sp = sp->se_next) { if ((sp->se_flags & SE_PRESENT) == 0) { sp->se_flags |= SE_SHUTDOWN; kill(sp->se_process, SIGHUP); } } return (state_func_t) multi_user; } /* * Block further logins. */ static state_func_t catatonia(void) { session_t *sp; for (sp = sessions; sp; sp = sp->se_next) sp->se_flags |= SE_SHUTDOWN; return (state_func_t) multi_user; } /* * Note SIGALRM. */ static void alrm_handler(int sig) { (void)sig; clang = 1; } /* * Bring the system down to single user. */ static state_func_t death(void) { int block, blocked; size_t len; /* Temporarily block suspend. */ len = sizeof(blocked); block = 1; if (sysctlbyname("kern.suspend_blocked", &blocked, &len, &block, sizeof(block)) == -1) blocked = 0; /* * Also revoke the TTY here. Because runshutdown() may reopen * the TTY whose getty we're killing here, there is no guarantee * runshutdown() will perform the initial open() call, causing * the terminal attributes to be misconfigured. */ revoke_ttys(); /* Try to run the rc.shutdown script within a period of time */ runshutdown(); /* Unblock suspend if we blocked it. */ if (!blocked) sysctlbyname("kern.suspend_blocked", NULL, NULL, &blocked, sizeof(blocked)); return (state_func_t) death_single; } /* * Do what is necessary to reinitialize single user mode or reboot * from an incomplete state. */ static state_func_t death_single(void) { int i; pid_t pid; static const int death_sigs[2] = { SIGTERM, SIGKILL }; revoke(_PATH_CONSOLE); for (i = 0; i < 2; ++i) { if (kill(-1, death_sigs[i]) == -1 && errno == ESRCH) return (state_func_t) single_user; clang = 0; alarm(DEATH_WATCH); do if ((pid = waitpid(-1, (int *)0, 0)) != -1) collect_child(pid); while (clang == 0 && errno != ECHILD); if (errno == ECHILD) return (state_func_t) single_user; } warning("some processes would not die; ps axl advised"); return (state_func_t) single_user; } static void revoke_ttys(void) { session_t *sp; for (sp = sessions; sp; sp = sp->se_next) { sp->se_flags |= SE_SHUTDOWN; kill(sp->se_process, SIGHUP); revoke(sp->se_device); } } /* * Run the system shutdown script. * * Exit codes: XXX I should document more * -2 shutdown script terminated abnormally * -1 fatal error - can't run script * 0 good. * >0 some error (exit code) */ static int runshutdown(void) { pid_t pid, wpid; int status; int shutdowntimeout; size_t len; char *argv[4]; struct stat sb; /* * rc.shutdown is optional, so to prevent any unnecessary * complaints from the shell we simply don't run it if the * file does not exist. If the stat() here fails for other * reasons, we'll let the shell complain. */ if (stat(_PATH_RUNDOWN, &sb) == -1 && errno == ENOENT) return 0; if ((pid = fork()) == 0) { char _sh[] = "sh"; char _reboot[] = "reboot"; char _single[] = "single"; char _path_rundown[] = _PATH_RUNDOWN; argv[0] = _sh; argv[1] = _path_rundown; argv[2] = Reboot ? _reboot : _single; argv[3] = NULL; execute_script(argv); _exit(1); /* force single user mode */ } if (pid == -1) { emergency("can't fork for %s: %m", _PATH_RUNDOWN); while (waitpid(-1, (int *) 0, WNOHANG) > 0) continue; sleep(STALL_TIMEOUT); return -1; } len = sizeof(shutdowntimeout); if (sysctlbyname("kern.init_shutdown_timeout", &shutdowntimeout, &len, NULL, 0) == -1 || shutdowntimeout < 2) shutdowntimeout = DEATH_SCRIPT; alarm(shutdowntimeout); clang = 0; /* * Copied from single_user(). This is a bit paranoid. * Use the same ALRM handler. */ do { if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1) collect_child(wpid); if (clang == 1) { /* we were waiting for the sub-shell */ kill(wpid, SIGTERM); warning("timeout expired for %s: %m; going to " "single user mode", _PATH_RUNDOWN); return -1; } if (wpid == -1) { if (errno == EINTR) continue; warning("wait for %s failed: %m; going to " "single user mode", _PATH_RUNDOWN); return -1; } if (wpid == pid && WIFSTOPPED(status)) { warning("init: %s stopped, restarting\n", _PATH_RUNDOWN); kill(pid, SIGCONT); wpid = -1; } } while (wpid != pid && !clang); /* Turn off the alarm */ alarm(0); if (WIFSIGNALED(status) && WTERMSIG(status) == SIGTERM && requested_transition == catatonia) { /* * /etc/rc.shutdown executed /sbin/reboot; * wait for the end quietly */ sigset_t s; sigfillset(&s); for (;;) sigsuspend(&s); } if (!WIFEXITED(status)) { warning("%s terminated abnormally, going to " "single user mode", _PATH_RUNDOWN); return -2; } if ((status = WEXITSTATUS(status)) != 0) warning("%s returned status %d", _PATH_RUNDOWN, status); return status; } static char * strk(char *p) { static char *t; char *q; int c; if (p) t = p; if (!t) return 0; c = *t; while (c == ' ' || c == '\t' ) c = *++t; if (!c) { t = 0; return 0; } q = t; if (c == '\'') { c = *++t; q = t; while (c && c != '\'') c = *++t; if (!c) /* unterminated string */ q = t = 0; else *t++ = 0; } else { while (c && c != ' ' && c != '\t' ) c = *++t; *t++ = 0; if (!c) t = 0; } return q; } #ifdef LOGIN_CAP static void setprocresources(const char *cname) { login_cap_t *lc; if ((lc = login_getclassbyname(cname, NULL)) != NULL) { setusercontext(lc, (struct passwd*)NULL, 0, LOGIN_SETENV | LOGIN_SETPRIORITY | LOGIN_SETRESOURCES | LOGIN_SETLOGINCLASS | LOGIN_SETCPUMASK); login_close(lc); } } #endif + +/* + * Run /etc/rc.final to execute scripts after all user processes have been + * terminated. + */ +static void +runfinal(void) +{ + struct stat sb; + pid_t other_pid, pid; + sigset_t mask; + + /* Avoid any surprises. */ + alarm(0); + + /* rc.final is optional. */ + if (stat(_PATH_RUNFINAL, &sb) == -1 && errno == ENOENT) + return; + if (access(_PATH_RUNFINAL, X_OK) != 0) { + warning("%s exists, but not executable", _PATH_RUNFINAL); + return; + } + + pid = fork(); + if (pid == 0) { + /* + * Reopen stdin/stdout/stderr so that scripts can write to + * console. + */ + close(0); + open(_PATH_DEVNULL, O_RDONLY); + close(1); + close(2); + open_console(); + dup2(1, 2); + sigemptyset(&mask); + sigprocmask(SIG_SETMASK, &mask, NULL); + signal(SIGCHLD, SIG_DFL); + execl(_PATH_RUNFINAL, _PATH_RUNFINAL, NULL); + perror("execl(" _PATH_RUNFINAL ") failed"); + exit(1); + } + + /* Wait for rc.final script to exit */ + while ((other_pid = waitpid(-1, NULL, 0)) != pid && other_pid > 0) { + continue; + } +} diff --git a/sbin/init/pathnames.h b/sbin/init/pathnames.h index 2ed366e4f7f7..7dc75ba52491 100644 --- a/sbin/init/pathnames.h +++ b/sbin/init/pathnames.h @@ -1,45 +1,46 @@ /*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 1991, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * Donn Seeley at Berkeley Software Design, Inc. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)pathnames.h 8.1 (Berkeley) 6/5/93 * $FreeBSD$ */ #include #define _PATH_INITLOG "/var/log/init.log" #define _PATH_SLOGGER "/sbin/session_logger" #define _PATH_RUNCOM "/etc/rc" #define _PATH_RUNDOWN "/etc/rc.shutdown" +#define _PATH_RUNFINAL "/etc/rc.final" #define _PATH_REROOT "/dev/reroot" #define _PATH_REROOT_INIT _PATH_REROOT "/init"