d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
6a7d5cb645
freebsd-dev/sbin/init/init.c
Ralf S. Engelschall 724447ac41 Fix system shutdown timeout handling by again supporting longer running 
shutdown procedures (which have a duration of more than 120 seconds).

We have two user-space affecting shutdown timeouts: a "soft" one in
/etc/rc.shutdown and a "hard" one in init(8). The first one can be
configured via /etc/rc.conf variable "rcshutdown_timeout" and defaults
to 30 seconds. The second one was originally (in 1998) intended to be
configured via sysctl(8) variable "kern.shutdown_timeout" and defaults
to 120 seconds.

Unfortunately, the "kern.shutdown_timeout" was declared "unused" in 1999
(as it obviously is actually not used within the kernel itself) and
hence was intentionally but misleadingly removed in revision 1.107 from
init_main.c. Kernel sysctl(8) variables are certainly a wrong way to
control user-space processes in general, but in this particular case the
sysctl(8) variable should have remained as it supports init(8), which
isn't passed command line flags (which in turn could have been set via
/etc/rc.conf), etc.

As there is already a similar "kern.init_path" sysctl(8) variable which
directly affects init(8), resurrect the init(8) shutdown timeout under
sysctl(8) variable "kern.init_shutdown_timeout". But this time document
it as being intentionally unused within the kernel and used by init(8).
Also document it in the manpages init(8) and rc.conf(5).

Reviewed by: phk
MFC after: 2 weeks
2005-09-15 13:16:07 +00:00

1636 lines
36 KiB
C
Raw Blame History

/*-
* 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.
* 4. 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 <sys/param.h>
#include <sys/ioctl.h>
#include <sys/mount.h>
#include <sys/sysctl.h>
#include <sys/wait.h>
#include <sys/stat.h>
#include <sys/uio.h>
#include <db.h>
#include <errno.h>
#include <fcntl.h>
#include <libutil.h>
#include <paths.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <time.h>
#include <ttyent.h>
#include <unistd.h>
#include <sys/reboot.h>
#include <err.h>
#include <stdarg.h>
#ifdef SECURE
#include <pwd.h>
#endif
#ifdef LOGIN_CAP
#include <login_cap.h>
#endif
#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"
void handle(sig_t, ...);
void delset(sigset_t *, ...);
void stall(const char *, ...) __printflike(1, 2);
void warning(const char *, ...) __printflike(1, 2);
void emergency(const char *, ...) __printflike(1, 2);
void disaster(int);
void badsys(int);
int runshutdown(void);
static char *strk(char *);
/*
* 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);
state_func_t single_user(void);
state_func_t runcom(void);
state_func_t read_ttys(void);
state_func_t multi_user(void);
state_func_t clean_ttys(void);
state_func_t catatonia(void);
state_func_t death(void);
enum { AUTOBOOT, FASTBOOT } runcom_mode = AUTOBOOT;
#define FALSE 0
#define TRUE 1
int Reboot = FALSE;
int howto = RB_AUTOBOOT;
int devfs;
void transition(state_t);
state_t requested_transition = runcom;
void setctty(const char *);
typedef struct init_session {
int se_index; /* index of entry in ttys file */
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 */
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;
void free_session(session_t *);
session_t *new_session(session_t *, int, struct ttyent *);
session_t *sessions;
char **construct_argv(char *);
void start_window_system(session_t *);
void collect_child(pid_t);
pid_t start_getty(session_t *);
void transition_handler(int);
void alrm_handler(int);
void setsecuritylevel(int);
int getsecuritylevel(void);
int setupargv(session_t *, struct ttyent *);
#ifdef LOGIN_CAP
void setprocresources(const char *);
#endif
int clang;
void clear_session_logs(session_t *);
int start_session_db(void);
void add_session(session_t *);
void del_session(session_t *);
session_t *find_session(pid_t);
DB *session_db;
/*
* The mother of all processes.
*/
int
main(int argc, char *argv[])
{
int c;
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;
default:
goto invalid;
}
kill(1, sig);
_exit(0);
} else
invalid:
errx(1, "invalid run-level ``%s''", argv[1]);
} else
#endif
errx(1, "already running");
}
/*
* Note that this does NOT open a file...
* Does 'init' deserve its own facility number?
*/
openlog("init", LOG_CONS|LOG_ODELAY, LOG_AUTH);
/*
* Create an initial session.
*/
if (setsid() < 0)
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, "dsf")) != -1)
switch (c) {
case 'd':
devfs = 1;
break;
case 's':
requested_transition = single_user;
break;
case 'f':
runcom_mode = FASTBOOT;
break;
default:
warning("unrecognized flag '-%c'", c);
break;
}
if (optind != argc)
warning("ignoring excess arguments");
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);
}
/*
* We catch or block signals rather than ignore them,
* so that they get reset on exec.
*/
handle(badsys, SIGSYS, 0);
handle(disaster, SIGABRT, SIGFPE, SIGILL, SIGSEGV,
SIGBUS, SIGXCPU, SIGXFSZ, 0);
handle(transition_handler, SIGHUP, SIGINT, SIGTERM, SIGTSTP,
SIGUSR1, SIGUSR2, 0);
handle(alrm_handler, SIGALRM, 0);
sigfillset(&mask);
delset(&mask, SIGABRT, SIGFPE, SIGILL, SIGSEGV, SIGBUS, SIGSYS,
SIGXCPU, SIGXFSZ, SIGHUP, SIGINT, SIGTERM, SIGTSTP, SIGALRM,
SIGUSR1, SIGUSR2, 0);
sigprocmask(SIG_SETMASK, &mask, (sigset_t *) 0);
sigemptyset(&sa.sa_mask);
sa.sa_flags = 0;
sa.sa_handler = SIG_IGN;
(void) sigaction(SIGTTIN, &sa, (struct sigaction *)0);
(void) sigaction(SIGTTOU, &sa, (struct sigaction *)0);
/*
* Paranoia.
*/
close(0);
close(1);
close(2);
/*
* Start the state machine.
*/
transition(requested_transition);
/*
* Should never reach here.
*/
return 1;
}
/*
* Associate a function with a signal handler.
*/
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, (struct sigaction *) 0);
}
va_end(ap);
}
/*
* Delete a set of signals from a mask.
*/
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.
*/
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.
*/
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.
*/
void
emergency(const char *message, ...)
{
va_list ap;
va_start(ap, message);
vsyslog(LOG_EMERG, message, ap);
va_end(ap);
}
/*
* Catch a SIGSYS signal.
*
* These may arise if a system does not support sysctl.
* We tolerate up to 25 of these, then throw in the towel.
*/
void
badsys(int sig)
{
static int badcount = 0;
if (badcount++ < 25)
return;
disaster(sig);
}
/*
* Catch an unexpected signal.
*/
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.
*/
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: %s",
strerror(errno));
return (-1);
}
return (curlevel);
#else
return (-1);
#endif
}
/*
* Set the security level of the kernel.
*/
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: %s",
curlevel, newlevel, strerror(errno));
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.
*/
void
transition(state_t s)
{
for (;;)
s = (state_t) (*s)();
}
/*
* Close out the accounting files for a login session.
* NB: should send a message to the session logger to avoid blocking.
*/
void
clear_session_logs(session_t *sp)
{
char *line = sp->se_device + sizeof(_PATH_DEV) - 1;
if (logout(line))
logwtmp(line, "", "");
}
/*
* Start a session and allocate a controlling terminal.
* Only called by children of init after forking.
*/
void
setctty(const char *name)
{
int fd;
(void) revoke(name);
if ((fd = open(name, O_RDWR)) == -1) {
stall("can't open %s: %m", name);
_exit(1);
}
if (login_tty(fd) == -1) {
stall("can't get %s for controlling terminal: %m", name);
_exit(1);
}
}
/*
* Bring the system up single user.
*/
state_func_t
single_user(void)
{
pid_t pid, wpid;
int status;
sigset_t mask;
const char *shell = _PATH_BSHELL;
char *argv[2];
#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();
alarm(2);
pause();
reboot(howto);
_exit(0);
}
if ((pid = fork()) == 0) {
/*
* Start the single user session.
*/
setctty(_PATH_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_FILENO, banner, sizeof banner - 1);
for (;;) {
clear = getpass("Password:");
if (clear == 0 || *clear == '\0')
_exit(0);
password = crypt(clear, pp->pw_passwd);
bzero(clear, _PASSWORD_LEN);
if (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 " _PATH_BSHELL ": "
(void)write(STDERR_FILENO,
SHREQUEST, sizeof(SHREQUEST) - 1);
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, (sigset_t *) 0);
/*
* Fire off a shell.
* If the default one doesn't work, try the Bourne shell.
*/
char name[] = "-sh";
argv[0] = name;
argv[1] = 0;
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.");
sleep(STALL_TIMEOUT);
_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.
*/
state_func_t
runcom(void)
{
pid_t pid, wpid;
int status;
char *argv[4];
struct sigaction sa;
if ((pid = fork()) == 0) {
sigemptyset(&sa.sa_mask);
sa.sa_flags = 0;
sa.sa_handler = SIG_IGN;
(void) sigaction(SIGTSTP, &sa, (struct sigaction *)0);
(void) sigaction(SIGHUP, &sa, (struct sigaction *)0);
setctty(_PATH_CONSOLE);
char _sh[] = "sh";
char _path_runcom[] = _PATH_RUNCOM;
char _autoboot[] = "autoboot";
argv[0] = _sh;
argv[1] = _path_runcom;
argv[2] = runcom_mode == AUTOBOOT ? _autoboot : 0;
argv[3] = 0;
sigprocmask(SIG_SETMASK, &sa.sa_mask, (sigset_t *) 0);
#ifdef LOGIN_CAP
setprocresources(RESOURCE_RC);
#endif
execv(_PATH_BSHELL, argv);
stall("can't exec %s for %s: %m", _PATH_BSHELL, _PATH_RUNCOM);
_exit(1); /* force single user mode */
}
if (pid == -1) {
emergency("can't fork for %s on %s: %m",
_PATH_BSHELL, _PATH_RUNCOM);
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)
return (state_func_t) death;
if (errno == EINTR)
continue;
warning("wait for %s on %s failed: %m; going to single user mode",
_PATH_BSHELL, _PATH_RUNCOM);
return (state_func_t) single_user;
}
if (wpid == pid && WIFSTOPPED(status)) {
warning("init: %s on %s stopped, restarting\n",
_PATH_BSHELL, _PATH_RUNCOM);
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",
_PATH_BSHELL, _PATH_RUNCOM);
return (state_func_t) single_user;
}
if (WEXITSTATUS(status))
return (state_func_t) single_user;
runcom_mode = AUTOBOOT; /* the default */
/* NB: should send a message to the session logger to avoid blocking. */
logwtmp("~", "reboot", "");
return (state_func_t) read_ttys;
}
/*
* Open the session database.
*
* NB: We could pass in the size here; is it necessary?
*/
int
start_session_db(void)
{
if (session_db && (*session_db->close)(session_db))
emergency("session database close: %s", strerror(errno));
if ((session_db = dbopen(NULL, O_RDWR, 0, DB_HASH, NULL)) == 0) {
emergency("session database open: %s", strerror(errno));
return (1);
}
return (0);
}
/*
* Add a new login session.
*/
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: %s", sp->se_process, strerror(errno));
}
/*
* Delete an old login session.
*/
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: %s", sp->se_process, strerror(errno));
}
/*
* Look up a login session by pid.
*/
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.
*/
char **
construct_argv(char *command)
{
int argc = 0;
char **argv = (char **) malloc(((strlen(command) + 1) / 2 + 1)
* sizeof (char *));
if ((argv[argc++] = strk(command)) == 0) {
free(argv);
return (NULL);
}
while ((argv[argc++] = strk((char *) 0)) != NULL)
continue;
return argv;
}
/*
* Deallocate a session descriptor.
*/
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.
*/
session_t *
new_session(session_t *sprev, int session_index, struct ttyent *typ)
{
session_t *sp;
int fd;
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_index = session_index;
sp->se_flags |= SE_PRESENT;
sp->se_device = malloc(sizeof(_PATH_DEV) + strlen(typ->ty_name));
(void) sprintf(sp->se_device, "%s%s", _PATH_DEV, typ->ty_name);
/*
* Attempt to open the device, if we get "device not configured"
* then don't add the device to the session list.
*/
if ((fd = open(sp->se_device, O_RDONLY | O_NONBLOCK, 0)) < 0) {
if (errno == ENXIO) {
free_session(sp);
return (0);
}
} else
close(fd);
if (setupargv(sp, typ) == 0) {
free_session(sp);
return (0);
}
sp->se_next = 0;
if (sprev == 0) {
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.
*/
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);
}
sp->se_getty = malloc(strlen(typ->ty_getty) + strlen(typ->ty_name) + 2);
(void) sprintf(sp->se_getty, "%s %s", typ->ty_getty, typ->ty_name);
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 == 0) {
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 == 0) {
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.
*/
state_func_t
read_ttys(void)
{
int session_index = 0;
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) {
if (sp->se_process)
clear_session_logs(sp);
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, ++session_index, typ)) != NULL)
sp = snext;
endttyent();
return (state_func_t) multi_user;
}
/*
* Start a window system running.
*/
void
start_window_system(session_t *sp)
{
pid_t pid;
sigset_t mask;
char term[64], *env[2];
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)
return;
sigemptyset(&mask);
sigprocmask(SIG_SETMASK, &mask, (sigset_t *) 0);
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=");
strncat(term, sp->se_type, sizeof(term) - 6);
env[0] = term;
env[1] = 0;
}
else
env[0] = 0;
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.
*/
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, (sigset_t *) 0);
#ifdef LOGIN_CAP
setprocresources(RESOURCE_GETTY);
#endif
if (sp->se_type) {
/* Don't use malloc after fork */
strcpy(term, "TERM=");
strncat(term, sp->se_type, sizeof(term) - 6);
env[0] = term;
env[1] = 0;
}
else
env[0] = 0;
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);
}
/*
* Collect exit status for a child.
* If an exiting login, start a new login running.
*/
void
collect_child(pid_t pid)
{
session_t *sp, *sprev, *snext;
if (! sessions)
return;
if (! (sp = find_session(pid)))
return;
clear_session_logs(sp);
del_session(sp);
sp->se_process = 0;
if (sp->se_flags & SE_SHUTDOWN) {
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.
*/
void
transition_handler(int sig)
{
switch (sig) {
case SIGHUP:
requested_transition = clean_ttys;
break;
case SIGUSR2:
howto = RB_POWEROFF;
case SIGUSR1:
howto |= RB_HALT;
case SIGINT:
Reboot = TRUE;
case SIGTERM:
requested_transition = death;
break;
case SIGTSTP:
requested_transition = catatonia;
break;
default:
requested_transition = 0;
break;
}
}
/*
* Take the system multiuser.
*/
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 ((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...
*/
state_func_t
clean_ttys(void)
{
session_t *sp, *sprev;
struct ttyent *typ;
int session_index = 0;
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) {
++session_index;
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 (sp->se_index != session_index) {
warning("port %s changed utmp index from %d to %d",
sp->se_device, sp->se_index,
session_index);
sp->se_index = session_index;
}
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, session_index, 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.
*/
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.
*/
void
alrm_handler(int sig)
{
(void)sig;
clang = 1;
}
/*
* Bring the system down to single user.
*/
state_func_t
death(void)
{
session_t *sp;
int i;
pid_t pid;
static const int death_sigs[2] = { SIGTERM, SIGKILL };
/* NB: should send a message to the session logger to avoid blocking. */
logwtmp("~", "shutdown", "");
for (sp = sessions; sp; sp = sp->se_next) {
sp->se_flags |= SE_SHUTDOWN;
kill(sp->se_process, SIGHUP);
}
/* Try to run the rc.shutdown script within a period of time */
(void) runshutdown();
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;
}
/*
* 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)
*/
int
runshutdown(void)
{
pid_t pid, wpid;
int status;
int shutdowntimeout;
size_t len;
char *argv[4];
struct sigaction sa;
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) {
int fd;
/* Assume that init already grab console as ctty before */
sigemptyset(&sa.sa_mask);
sa.sa_flags = 0;
sa.sa_handler = SIG_IGN;
(void) sigaction(SIGTSTP, &sa, (struct sigaction *)0);
(void) sigaction(SIGHUP, &sa, (struct sigaction *)0);
if ((fd = open(_PATH_CONSOLE, O_RDWR)) == -1)
warning("can't open %s: %m", _PATH_CONSOLE);
else {
(void) dup2(fd, 0);
(void) dup2(fd, 1);
(void) dup2(fd, 2);
if (fd > 2)
close(fd);
}
/*
* Run the shutdown script.
*/
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] = 0;
sigprocmask(SIG_SETMASK, &sa.sa_mask, (sigset_t *) 0);
#ifdef LOGIN_CAP
setprocresources(RESOURCE_RC);
#endif
execv(_PATH_BSHELL, argv);
warning("can't exec %s for %s: %m", _PATH_BSHELL, _PATH_RUNDOWN);
_exit(1); /* force single user mode */
}
if (pid == -1) {
emergency("can't fork for %s on %s: %m",
_PATH_BSHELL, _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 on %s: %m; going to single user mode",
_PATH_BSHELL, _PATH_RUNDOWN);
return -1;
}
if (wpid == -1) {
if (errno == EINTR)
continue;
warning("wait for %s on %s failed: %m; going to single user mode",
_PATH_BSHELL, _PATH_RUNDOWN);
return -1;
}
if (wpid == pid && WIFSTOPPED(status)) {
warning("init: %s on %s stopped, restarting\n",
_PATH_BSHELL, _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 on %s terminated abnormally, going to single user mode",
_PATH_BSHELL, _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
void
setprocresources(const char *cname)
{
login_cap_t *lc;
if ((lc = login_getclassbyname(cname, NULL)) != NULL) {
setusercontext(lc, (struct passwd*)NULL, 0, LOGIN_SETPRIORITY|LOGIN_SETRESOURCES);
login_close(lc);
}
}
#endif
Reference in New Issue View Git Blame Copy Permalink