mirror of
https://github.com/sheumann/hush.git
synced 2024-08-14 11:28:58 +00:00
1133 lines
28 KiB
C
1133 lines
28 KiB
C
/* vi: set sw=4 ts=4: */
|
|
/*
|
|
* Mini init implementation for busybox
|
|
*
|
|
* Copyright (C) 1995, 1996 by Bruce Perens <bruce@pixar.com>.
|
|
* Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
|
|
* Adjusted by so many folks, it's impossible to keep track.
|
|
*
|
|
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
|
|
*/
|
|
|
|
#include "busybox.h"
|
|
#include <errno.h>
|
|
#include <paths.h>
|
|
#include <signal.h>
|
|
#include <sys/ioctl.h>
|
|
#include <sys/wait.h>
|
|
#include <sys/reboot.h>
|
|
|
|
#include "init_shared.h"
|
|
|
|
#if ENABLE_SYSLOGD
|
|
# include <sys/syslog.h>
|
|
#endif
|
|
|
|
#define INIT_BUFFS_SIZE 256
|
|
|
|
/* From <linux/vt.h> */
|
|
struct vt_stat {
|
|
unsigned short v_active; /* active vt */
|
|
unsigned short v_signal; /* signal to send */
|
|
unsigned short v_state; /* vt bitmask */
|
|
};
|
|
enum { VT_GETSTATE = 0x5603 }; /* get global vt state info */
|
|
|
|
/* From <linux/serial.h> */
|
|
struct serial_struct {
|
|
int type;
|
|
int line;
|
|
unsigned int port;
|
|
int irq;
|
|
int flags;
|
|
int xmit_fifo_size;
|
|
int custom_divisor;
|
|
int baud_base;
|
|
unsigned short close_delay;
|
|
char io_type;
|
|
char reserved_char[1];
|
|
int hub6;
|
|
unsigned short closing_wait; /* time to wait before closing */
|
|
unsigned short closing_wait2; /* no longer used... */
|
|
unsigned char *iomem_base;
|
|
unsigned short iomem_reg_shift;
|
|
unsigned int port_high;
|
|
unsigned long iomap_base; /* cookie passed into ioremap */
|
|
int reserved[1];
|
|
};
|
|
|
|
#ifndef _PATH_STDPATH
|
|
#define _PATH_STDPATH "/usr/bin:/bin:/usr/sbin:/sbin"
|
|
#endif
|
|
|
|
#if ENABLE_FEATURE_INIT_COREDUMPS
|
|
/*
|
|
* When a file named CORE_ENABLE_FLAG_FILE exists, setrlimit is called
|
|
* before processes are spawned to set core file size as unlimited.
|
|
* This is for debugging only. Don't use this is production, unless
|
|
* you want core dumps lying about....
|
|
*/
|
|
#define CORE_ENABLE_FLAG_FILE "/.init_enable_core"
|
|
#include <sys/resource.h>
|
|
#endif
|
|
|
|
#define INITTAB "/etc/inittab" /* inittab file location */
|
|
#ifndef INIT_SCRIPT
|
|
#define INIT_SCRIPT "/etc/init.d/rcS" /* Default sysinit script. */
|
|
#endif
|
|
|
|
#define MAXENV 16 /* Number of env. vars */
|
|
|
|
#define CONSOLE_BUFF_SIZE 32
|
|
|
|
/* Allowed init action types */
|
|
#define SYSINIT 0x001
|
|
#define RESPAWN 0x002
|
|
#define ASKFIRST 0x004
|
|
#define WAIT 0x008
|
|
#define ONCE 0x010
|
|
#define CTRLALTDEL 0x020
|
|
#define SHUTDOWN 0x040
|
|
#define RESTART 0x080
|
|
|
|
/* A mapping between "inittab" action name strings and action type codes. */
|
|
struct init_action_type {
|
|
const char *name;
|
|
int action;
|
|
};
|
|
|
|
static const struct init_action_type actions[] = {
|
|
{"sysinit", SYSINIT},
|
|
{"respawn", RESPAWN},
|
|
{"askfirst", ASKFIRST},
|
|
{"wait", WAIT},
|
|
{"once", ONCE},
|
|
{"ctrlaltdel", CTRLALTDEL},
|
|
{"shutdown", SHUTDOWN},
|
|
{"restart", RESTART},
|
|
{0, 0}
|
|
};
|
|
|
|
/* Set up a linked list of init_actions, to be read from inittab */
|
|
struct init_action {
|
|
pid_t pid;
|
|
char command[INIT_BUFFS_SIZE];
|
|
char terminal[CONSOLE_BUFF_SIZE];
|
|
struct init_action *next;
|
|
int action;
|
|
};
|
|
|
|
/* Static variables */
|
|
static struct init_action *init_action_list = NULL;
|
|
static char console[CONSOLE_BUFF_SIZE] = CONSOLE_DEV;
|
|
|
|
#if !ENABLE_SYSLOGD
|
|
static char *log_console = VC_5;
|
|
#endif
|
|
#if !ENABLE_DEBUG_INIT
|
|
static sig_atomic_t got_cont = 0;
|
|
#endif
|
|
|
|
enum {
|
|
LOG = 0x1,
|
|
CONSOLE = 0x2,
|
|
|
|
#if ENABLE_FEATURE_EXTRA_QUIET
|
|
MAYBE_CONSOLE = 0x0,
|
|
#else
|
|
MAYBE_CONSOLE = CONSOLE,
|
|
#endif
|
|
|
|
#ifndef RB_HALT_SYSTEM
|
|
RB_HALT_SYSTEM = 0xcdef0123, /* FIXME: this overflows enum */
|
|
RB_ENABLE_CAD = 0x89abcdef,
|
|
RB_DISABLE_CAD = 0,
|
|
RB_POWER_OFF = 0x4321fedc,
|
|
RB_AUTOBOOT = 0x01234567,
|
|
#endif
|
|
};
|
|
|
|
static const char * const environment[] = {
|
|
"HOME=/",
|
|
"PATH=" _PATH_STDPATH,
|
|
"SHELL=/bin/sh",
|
|
"USER=root",
|
|
NULL
|
|
};
|
|
|
|
/* Function prototypes */
|
|
static void delete_init_action(struct init_action *a);
|
|
static int waitfor(const struct init_action *a, pid_t pid);
|
|
#if !ENABLE_DEBUG_INIT
|
|
static void shutdown_signal(int sig);
|
|
#endif
|
|
|
|
#if !ENABLE_DEBUG_INIT
|
|
static void loop_forever(void)
|
|
{
|
|
while (1)
|
|
sleep(1);
|
|
}
|
|
#endif
|
|
|
|
/* Print a message to the specified device.
|
|
* Device may be bitwise-or'd from LOG | CONSOLE */
|
|
#if ENABLE_DEBUG_INIT
|
|
#define messageD message
|
|
#else
|
|
#define messageD(...) do {} while (0)
|
|
#endif
|
|
static void message(int device, const char *fmt, ...)
|
|
__attribute__ ((format(printf, 2, 3)));
|
|
static void message(int device, const char *fmt, ...)
|
|
{
|
|
va_list arguments;
|
|
int l;
|
|
RESERVE_CONFIG_BUFFER(msg, 1024);
|
|
#if !ENABLE_SYSLOGD
|
|
static int log_fd = -1;
|
|
#endif
|
|
|
|
msg[0] = '\r';
|
|
va_start(arguments, fmt);
|
|
l = vsnprintf(msg + 1, 1024 - 2, fmt, arguments) + 1;
|
|
va_end(arguments);
|
|
|
|
#if ENABLE_SYSLOGD
|
|
/* Log the message to syslogd */
|
|
if (device & LOG) {
|
|
/* don`t out "\r\n" */
|
|
openlog(applet_name, 0, LOG_DAEMON);
|
|
syslog(LOG_INFO, "%s", msg + 1);
|
|
closelog();
|
|
}
|
|
|
|
msg[l++] = '\n';
|
|
msg[l] = 0;
|
|
#else
|
|
|
|
msg[l++] = '\n';
|
|
msg[l] = 0;
|
|
/* Take full control of the log tty, and never close it.
|
|
* It's mine, all mine! Muhahahaha! */
|
|
if (log_fd < 0) {
|
|
if ((log_fd = device_open(log_console, O_RDWR | O_NONBLOCK | O_NOCTTY)) < 0) {
|
|
log_fd = -2;
|
|
bb_error_msg("bummer, can't write to log on %s!", log_console);
|
|
device = CONSOLE;
|
|
} else {
|
|
fcntl(log_fd, F_SETFD, FD_CLOEXEC);
|
|
}
|
|
}
|
|
if ((device & LOG) && (log_fd >= 0)) {
|
|
full_write(log_fd, msg, l);
|
|
}
|
|
#endif
|
|
|
|
if (device & CONSOLE) {
|
|
int fd = device_open(CONSOLE_DEV,
|
|
O_WRONLY | O_NOCTTY | O_NONBLOCK);
|
|
/* Always send console messages to /dev/console so people will see them. */
|
|
if (fd >= 0) {
|
|
full_write(fd, msg, l);
|
|
close(fd);
|
|
#if ENABLE_DEBUG_INIT
|
|
/* all descriptors may be closed */
|
|
} else {
|
|
bb_error_msg("bummer, can't print: ");
|
|
va_start(arguments, fmt);
|
|
vfprintf(stderr, fmt, arguments);
|
|
va_end(arguments);
|
|
#endif
|
|
}
|
|
}
|
|
RELEASE_CONFIG_BUFFER(msg);
|
|
}
|
|
|
|
/* Set terminal settings to reasonable defaults */
|
|
static void set_term(void)
|
|
{
|
|
struct termios tty;
|
|
|
|
tcgetattr(STDIN_FILENO, &tty);
|
|
|
|
/* set control chars */
|
|
tty.c_cc[VINTR] = 3; /* C-c */
|
|
tty.c_cc[VQUIT] = 28; /* C-\ */
|
|
tty.c_cc[VERASE] = 127; /* C-? */
|
|
tty.c_cc[VKILL] = 21; /* C-u */
|
|
tty.c_cc[VEOF] = 4; /* C-d */
|
|
tty.c_cc[VSTART] = 17; /* C-q */
|
|
tty.c_cc[VSTOP] = 19; /* C-s */
|
|
tty.c_cc[VSUSP] = 26; /* C-z */
|
|
|
|
/* use line dicipline 0 */
|
|
tty.c_line = 0;
|
|
|
|
/* Make it be sane */
|
|
tty.c_cflag &= CBAUD | CBAUDEX | CSIZE | CSTOPB | PARENB | PARODD;
|
|
tty.c_cflag |= CREAD | HUPCL | CLOCAL;
|
|
|
|
|
|
/* input modes */
|
|
tty.c_iflag = ICRNL | IXON | IXOFF;
|
|
|
|
/* output modes */
|
|
tty.c_oflag = OPOST | ONLCR;
|
|
|
|
/* local modes */
|
|
tty.c_lflag =
|
|
ISIG | ICANON | ECHO | ECHOE | ECHOK | ECHOCTL | ECHOKE | IEXTEN;
|
|
|
|
tcsetattr(STDIN_FILENO, TCSANOW, &tty);
|
|
}
|
|
|
|
static void console_init(void)
|
|
{
|
|
int fd;
|
|
int tried = 0;
|
|
struct vt_stat vt;
|
|
struct serial_struct sr;
|
|
char *s;
|
|
|
|
if ((s = getenv("CONSOLE")) != NULL || (s = getenv("console")) != NULL) {
|
|
safe_strncpy(console, s, sizeof(console));
|
|
} else {
|
|
/* 2.2 kernels: identify the real console backend and try to use it */
|
|
if (ioctl(0, TIOCGSERIAL, &sr) == 0) {
|
|
/* this is a serial console */
|
|
snprintf(console, sizeof(console) - 1, SC_FORMAT, sr.line);
|
|
} else if (ioctl(0, VT_GETSTATE, &vt) == 0) {
|
|
/* this is linux virtual tty */
|
|
snprintf(console, sizeof(console) - 1, VC_FORMAT, vt.v_active);
|
|
} else {
|
|
safe_strncpy(console, CONSOLE_DEV, sizeof(console));
|
|
tried++;
|
|
}
|
|
}
|
|
|
|
while ((fd = open(console, O_RDONLY | O_NONBLOCK)) < 0 && tried < 2) {
|
|
/* Can't open selected console -- try
|
|
logical system console and VT_MASTER */
|
|
safe_strncpy(console, (tried == 0 ? CONSOLE_DEV : CURRENT_VC),
|
|
sizeof(console));
|
|
tried++;
|
|
}
|
|
if (fd < 0) {
|
|
/* Perhaps we should panic here? */
|
|
#if !ENABLE_SYSLOGD
|
|
log_console =
|
|
#endif
|
|
safe_strncpy(console, bb_dev_null, sizeof(console));
|
|
} else {
|
|
s = getenv("TERM");
|
|
/* check for serial console */
|
|
if (ioctl(fd, TIOCGSERIAL, &sr) == 0) {
|
|
/* Force the TERM setting to vt102 for serial console --
|
|
* if TERM is set to linux (the default) */
|
|
if (s == NULL || strcmp(s, "linux") == 0)
|
|
putenv("TERM=vt102");
|
|
#if !ENABLE_SYSLOGD
|
|
log_console = console;
|
|
#endif
|
|
} else {
|
|
if (s == NULL)
|
|
putenv("TERM=linux");
|
|
}
|
|
close(fd);
|
|
}
|
|
messageD(LOG, "console=%s", console);
|
|
}
|
|
|
|
static void fixup_argv(int argc, char **argv, char *new_argv0)
|
|
{
|
|
int len;
|
|
|
|
/* Fix up argv[0] to be certain we claim to be init */
|
|
len = strlen(argv[0]);
|
|
memset(argv[0], 0, len);
|
|
safe_strncpy(argv[0], new_argv0, len + 1);
|
|
|
|
/* Wipe argv[1]-argv[N] so they don't clutter the ps listing */
|
|
len = 1;
|
|
while (argc > len) {
|
|
memset(argv[len], 0, strlen(argv[len]));
|
|
len++;
|
|
}
|
|
}
|
|
|
|
/* Open the new terminal device */
|
|
static void open_new_terminal(const char * const device, const int fail) {
|
|
struct stat sb;
|
|
|
|
if ((device_open(device, O_RDWR)) < 0) {
|
|
if (stat(device, &sb) != 0) {
|
|
message(LOG | CONSOLE, "device '%s' does not exist.", device);
|
|
} else {
|
|
message(LOG | CONSOLE, "Bummer, can't open %s", device);
|
|
}
|
|
if (fail)
|
|
_exit(1);
|
|
/* else */
|
|
#if !ENABLE_DEBUG_INIT
|
|
shutdown_signal(SIGUSR1);
|
|
#else
|
|
_exit(2);
|
|
#endif
|
|
}
|
|
}
|
|
|
|
static pid_t run(const struct init_action *a)
|
|
{
|
|
int i;
|
|
pid_t pid;
|
|
char *s, *tmpCmd, *cmd[INIT_BUFFS_SIZE], *cmdpath;
|
|
char buf[INIT_BUFFS_SIZE + 6]; /* INIT_BUFFS_SIZE+strlen("exec ")+1 */
|
|
sigset_t nmask, omask;
|
|
static const char press_enter[] =
|
|
#ifdef CUSTOMIZED_BANNER
|
|
#include CUSTOMIZED_BANNER
|
|
#endif
|
|
"\nPlease press Enter to activate this console. ";
|
|
|
|
/* Block sigchild while forking. */
|
|
sigemptyset(&nmask);
|
|
sigaddset(&nmask, SIGCHLD);
|
|
sigprocmask(SIG_BLOCK, &nmask, &omask);
|
|
|
|
if ((pid = fork()) == 0) {
|
|
|
|
/* Clean up */
|
|
close(0);
|
|
close(1);
|
|
close(2);
|
|
sigprocmask(SIG_SETMASK, &omask, NULL);
|
|
|
|
/* Reset signal handlers that were set by the parent process */
|
|
signal(SIGUSR1, SIG_DFL);
|
|
signal(SIGUSR2, SIG_DFL);
|
|
signal(SIGINT, SIG_DFL);
|
|
signal(SIGTERM, SIG_DFL);
|
|
signal(SIGHUP, SIG_DFL);
|
|
signal(SIGQUIT, SIG_DFL);
|
|
signal(SIGCONT, SIG_DFL);
|
|
signal(SIGSTOP, SIG_DFL);
|
|
signal(SIGTSTP, SIG_DFL);
|
|
|
|
/* Create a new session and make ourself the process
|
|
* group leader */
|
|
setsid();
|
|
|
|
/* Open the new terminal device */
|
|
open_new_terminal(a->terminal, 1);
|
|
|
|
/* Make sure the terminal will act fairly normal for us */
|
|
set_term();
|
|
/* Setup stdout, stderr for the new process so
|
|
* they point to the supplied terminal */
|
|
dup(0);
|
|
dup(0);
|
|
|
|
/* If the init Action requires us to wait, then force the
|
|
* supplied terminal to be the controlling tty. */
|
|
if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
|
|
|
|
/* Now fork off another process to just hang around */
|
|
if ((pid = fork()) < 0) {
|
|
message(LOG | CONSOLE, "Can't fork!");
|
|
_exit(1);
|
|
}
|
|
|
|
if (pid > 0) {
|
|
|
|
/* We are the parent -- wait till the child is done */
|
|
signal(SIGINT, SIG_IGN);
|
|
signal(SIGTSTP, SIG_IGN);
|
|
signal(SIGQUIT, SIG_IGN);
|
|
signal(SIGCHLD, SIG_DFL);
|
|
|
|
waitfor(NULL, pid);
|
|
/* See if stealing the controlling tty back is necessary */
|
|
if (tcgetpgrp(0) != getpid())
|
|
_exit(0);
|
|
|
|
/* Use a temporary process to steal the controlling tty. */
|
|
if ((pid = fork()) < 0) {
|
|
message(LOG | CONSOLE, "Can't fork!");
|
|
_exit(1);
|
|
}
|
|
if (pid == 0) {
|
|
setsid();
|
|
ioctl(0, TIOCSCTTY, 1);
|
|
_exit(0);
|
|
}
|
|
waitfor(NULL, pid);
|
|
_exit(0);
|
|
}
|
|
|
|
/* Now fall though to actually execute things */
|
|
}
|
|
|
|
/* See if any special /bin/sh requiring characters are present */
|
|
if (strpbrk(a->command, "~`!$^&*()=|\\{}[];\"'<>?") != NULL) {
|
|
cmd[0] = (char *)DEFAULT_SHELL;
|
|
cmd[1] = "-c";
|
|
cmd[2] = strcat(strcpy(buf, "exec "), a->command);
|
|
cmd[3] = NULL;
|
|
} else {
|
|
/* Convert command (char*) into cmd (char**, one word per string) */
|
|
strcpy(buf, a->command);
|
|
s = buf;
|
|
for (tmpCmd = buf, i = 0; (tmpCmd = strsep(&s, " \t")) != NULL;) {
|
|
if (*tmpCmd != '\0') {
|
|
cmd[i] = tmpCmd;
|
|
i++;
|
|
}
|
|
}
|
|
cmd[i] = NULL;
|
|
}
|
|
|
|
cmdpath = cmd[0];
|
|
|
|
/*
|
|
Interactive shells want to see a dash in argv[0]. This
|
|
typically is handled by login, argv will be setup this
|
|
way if a dash appears at the front of the command path
|
|
(like "-/bin/sh").
|
|
*/
|
|
|
|
if (*cmdpath == '-') {
|
|
|
|
/* skip over the dash */
|
|
++cmdpath;
|
|
|
|
/* find the last component in the command pathname */
|
|
s = bb_get_last_path_component(cmdpath);
|
|
|
|
/* make a new argv[0] */
|
|
if ((cmd[0] = malloc(strlen(s) + 2)) == NULL) {
|
|
message(LOG | CONSOLE, bb_msg_memory_exhausted);
|
|
cmd[0] = cmdpath;
|
|
} else {
|
|
cmd[0][0] = '-';
|
|
strcpy(cmd[0] + 1, s);
|
|
}
|
|
#if ENABLE_FEATURE_INIT_SCTTY
|
|
/* Establish this process as session leader and
|
|
* (attempt) to make the tty (if any) a controlling tty.
|
|
*/
|
|
(void) setsid();
|
|
(void) ioctl(0, TIOCSCTTY, 0/*don't steal it*/);
|
|
#endif
|
|
}
|
|
|
|
#if !defined(__UCLIBC__) || defined(__ARCH_HAS_MMU__)
|
|
if (a->action & ASKFIRST) {
|
|
char c;
|
|
/*
|
|
* Save memory by not exec-ing anything large (like a shell)
|
|
* before the user wants it. This is critical if swap is not
|
|
* enabled and the system has low memory. Generally this will
|
|
* be run on the second virtual console, and the first will
|
|
* be allowed to start a shell or whatever an init script
|
|
* specifies.
|
|
*/
|
|
messageD(LOG, "Waiting for enter to start '%s'"
|
|
"(pid %d, terminal %s)\n",
|
|
cmdpath, getpid(), a->terminal);
|
|
full_write(1, press_enter, sizeof(press_enter) - 1);
|
|
while (read(0, &c, 1) == 1 && c != '\n')
|
|
;
|
|
}
|
|
#endif
|
|
|
|
/* Log the process name and args */
|
|
message(LOG, "Starting pid %d, console %s: '%s'",
|
|
getpid(), a->terminal, cmdpath);
|
|
|
|
#if ENABLE_FEATURE_INIT_COREDUMPS
|
|
{
|
|
struct stat sb;
|
|
if (stat(CORE_ENABLE_FLAG_FILE, &sb) == 0) {
|
|
struct rlimit limit;
|
|
|
|
limit.rlim_cur = RLIM_INFINITY;
|
|
limit.rlim_max = RLIM_INFINITY;
|
|
setrlimit(RLIMIT_CORE, &limit);
|
|
}
|
|
}
|
|
#endif
|
|
|
|
/* Now run it. The new program will take over this PID,
|
|
* so nothing further in init.c should be run. */
|
|
execv(cmdpath, cmd);
|
|
|
|
/* We're still here? Some error happened. */
|
|
message(LOG | CONSOLE, "Bummer, cannot run '%s': %m", cmdpath);
|
|
_exit(-1);
|
|
}
|
|
sigprocmask(SIG_SETMASK, &omask, NULL);
|
|
return pid;
|
|
}
|
|
|
|
static int waitfor(const struct init_action *a, pid_t pid)
|
|
{
|
|
int runpid;
|
|
int status, wpid;
|
|
|
|
runpid = (NULL == a)? pid : run(a);
|
|
while (1) {
|
|
wpid = waitpid(runpid,&status,0);
|
|
if (wpid == runpid)
|
|
break;
|
|
if (wpid == -1 && errno == ECHILD) {
|
|
/* we missed its termination */
|
|
break;
|
|
}
|
|
/* FIXME other errors should maybe trigger an error, but allow
|
|
* the program to continue */
|
|
}
|
|
return wpid;
|
|
}
|
|
|
|
/* Run all commands of a particular type */
|
|
static void run_actions(int action)
|
|
{
|
|
struct init_action *a, *tmp;
|
|
|
|
for (a = init_action_list; a; a = tmp) {
|
|
tmp = a->next;
|
|
if (a->action == action) {
|
|
if (access(a->terminal, R_OK | W_OK)) {
|
|
delete_init_action(a);
|
|
} else if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
|
|
waitfor(a, 0);
|
|
delete_init_action(a);
|
|
} else if (a->action & ONCE) {
|
|
run(a);
|
|
delete_init_action(a);
|
|
} else if (a->action & (RESPAWN | ASKFIRST)) {
|
|
/* Only run stuff with pid==0. If they have
|
|
* a pid, that means it is still running */
|
|
if (a->pid == 0) {
|
|
a->pid = run(a);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
#if !ENABLE_DEBUG_INIT
|
|
static void init_reboot(unsigned long magic)
|
|
{
|
|
pid_t pid;
|
|
/* We have to fork here, since the kernel calls do_exit(0) in
|
|
* linux/kernel/sys.c, which can cause the machine to panic when
|
|
* the init process is killed.... */
|
|
pid = vfork();
|
|
if (pid == 0) { /* child */
|
|
reboot(magic);
|
|
_exit(0);
|
|
}
|
|
waitpid(pid, NULL, 0);
|
|
}
|
|
|
|
static void shutdown_system(void)
|
|
{
|
|
sigset_t block_signals;
|
|
|
|
/* run everything to be run at "shutdown". This is done _prior_
|
|
* to killing everything, in case people wish to use scripts to
|
|
* shut things down gracefully... */
|
|
run_actions(SHUTDOWN);
|
|
|
|
/* first disable all our signals */
|
|
sigemptyset(&block_signals);
|
|
sigaddset(&block_signals, SIGHUP);
|
|
sigaddset(&block_signals, SIGQUIT);
|
|
sigaddset(&block_signals, SIGCHLD);
|
|
sigaddset(&block_signals, SIGUSR1);
|
|
sigaddset(&block_signals, SIGUSR2);
|
|
sigaddset(&block_signals, SIGINT);
|
|
sigaddset(&block_signals, SIGTERM);
|
|
sigaddset(&block_signals, SIGCONT);
|
|
sigaddset(&block_signals, SIGSTOP);
|
|
sigaddset(&block_signals, SIGTSTP);
|
|
sigprocmask(SIG_BLOCK, &block_signals, NULL);
|
|
|
|
/* Allow Ctrl-Alt-Del to reboot system. */
|
|
init_reboot(RB_ENABLE_CAD);
|
|
|
|
message(CONSOLE | LOG, "The system is going down NOW !!");
|
|
sync();
|
|
|
|
/* Send signals to every process _except_ pid 1 */
|
|
message(CONSOLE | LOG, init_sending_format, "TERM");
|
|
kill(-1, SIGTERM);
|
|
sleep(1);
|
|
sync();
|
|
|
|
message(CONSOLE | LOG, init_sending_format, "KILL");
|
|
kill(-1, SIGKILL);
|
|
sleep(1);
|
|
|
|
sync();
|
|
}
|
|
|
|
static void exec_signal(int sig ATTRIBUTE_UNUSED)
|
|
{
|
|
struct init_action *a, *tmp;
|
|
sigset_t unblock_signals;
|
|
|
|
for (a = init_action_list; a; a = tmp) {
|
|
tmp = a->next;
|
|
if (a->action & RESTART) {
|
|
shutdown_system();
|
|
|
|
/* unblock all signals, blocked in shutdown_system() */
|
|
sigemptyset(&unblock_signals);
|
|
sigaddset(&unblock_signals, SIGHUP);
|
|
sigaddset(&unblock_signals, SIGQUIT);
|
|
sigaddset(&unblock_signals, SIGCHLD);
|
|
sigaddset(&unblock_signals, SIGUSR1);
|
|
sigaddset(&unblock_signals, SIGUSR2);
|
|
sigaddset(&unblock_signals, SIGINT);
|
|
sigaddset(&unblock_signals, SIGTERM);
|
|
sigaddset(&unblock_signals, SIGCONT);
|
|
sigaddset(&unblock_signals, SIGSTOP);
|
|
sigaddset(&unblock_signals, SIGTSTP);
|
|
sigprocmask(SIG_UNBLOCK, &unblock_signals, NULL);
|
|
|
|
/* Close whatever files are open. */
|
|
close(0);
|
|
close(1);
|
|
close(2);
|
|
|
|
/* Open the new terminal device */
|
|
open_new_terminal(a->terminal, 0);
|
|
|
|
/* Make sure the terminal will act fairly normal for us */
|
|
set_term();
|
|
/* Setup stdout, stderr on the supplied terminal */
|
|
dup(0);
|
|
dup(0);
|
|
|
|
messageD(CONSOLE | LOG, "Trying to re-exec %s", a->command);
|
|
execl(a->command, a->command, NULL);
|
|
|
|
message(CONSOLE | LOG, "exec of '%s' failed: %m",
|
|
a->command);
|
|
sync();
|
|
sleep(2);
|
|
init_reboot(RB_HALT_SYSTEM);
|
|
loop_forever();
|
|
}
|
|
}
|
|
}
|
|
|
|
static void shutdown_signal(int sig)
|
|
{
|
|
char *m;
|
|
int rb;
|
|
|
|
shutdown_system();
|
|
|
|
if (sig == SIGTERM) {
|
|
m = "reboot";
|
|
rb = RB_AUTOBOOT;
|
|
} else if (sig == SIGUSR2) {
|
|
m = "poweroff";
|
|
rb = RB_POWER_OFF;
|
|
} else {
|
|
m = "halt";
|
|
rb = RB_HALT_SYSTEM;
|
|
}
|
|
message(CONSOLE | LOG, "Requesting system %s.", m);
|
|
sync();
|
|
|
|
/* allow time for last message to reach serial console */
|
|
sleep(2);
|
|
|
|
init_reboot(rb);
|
|
loop_forever();
|
|
}
|
|
|
|
static void ctrlaltdel_signal(int sig ATTRIBUTE_UNUSED)
|
|
{
|
|
run_actions(CTRLALTDEL);
|
|
}
|
|
|
|
/* The SIGSTOP & SIGTSTP handler */
|
|
static void stop_handler(int sig ATTRIBUTE_UNUSED)
|
|
{
|
|
int saved_errno = errno;
|
|
|
|
got_cont = 0;
|
|
while (!got_cont)
|
|
pause();
|
|
got_cont = 0;
|
|
errno = saved_errno;
|
|
}
|
|
|
|
/* The SIGCONT handler */
|
|
static void cont_handler(int sig ATTRIBUTE_UNUSED)
|
|
{
|
|
got_cont = 1;
|
|
}
|
|
|
|
#endif /* ! ENABLE_DEBUG_INIT */
|
|
|
|
static void new_init_action(int action, const char *command, const char *cons)
|
|
{
|
|
struct init_action *new_action, *a, *last;
|
|
|
|
if (*cons == '\0')
|
|
cons = console;
|
|
|
|
if (strcmp(cons, bb_dev_null) == 0 && (action & ASKFIRST))
|
|
return;
|
|
|
|
new_action = xzalloc(sizeof(struct init_action));
|
|
|
|
/* Append to the end of the list */
|
|
for (a = last = init_action_list; a; a = a->next) {
|
|
/* don't enter action if it's already in the list,
|
|
* but do overwrite existing actions */
|
|
if ((strcmp(a->command, command) == 0) &&
|
|
(strcmp(a->terminal, cons) ==0)) {
|
|
a->action = action;
|
|
free(new_action);
|
|
return;
|
|
}
|
|
last = a;
|
|
}
|
|
if (last) {
|
|
last->next = new_action;
|
|
} else {
|
|
init_action_list = new_action;
|
|
}
|
|
strcpy(new_action->command, command);
|
|
new_action->action = action;
|
|
strcpy(new_action->terminal, cons);
|
|
messageD(LOG|CONSOLE, "command='%s' action='%d' terminal='%s'\n",
|
|
new_action->command, new_action->action, new_action->terminal);
|
|
}
|
|
|
|
static void delete_init_action(struct init_action *action)
|
|
{
|
|
struct init_action *a, *b = NULL;
|
|
|
|
for (a = init_action_list; a; b = a, a = a->next) {
|
|
if (a == action) {
|
|
if (b == NULL) {
|
|
init_action_list = a->next;
|
|
} else {
|
|
b->next = a->next;
|
|
}
|
|
free(a);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
|
|
* then parse_inittab() simply adds in some default
|
|
* actions(i.e., runs INIT_SCRIPT and then starts a pair
|
|
* of "askfirst" shells). If CONFIG_FEATURE_USE_INITTAB
|
|
* _is_ defined, but /etc/inittab is missing, this
|
|
* results in the same set of default behaviors.
|
|
*/
|
|
static void parse_inittab(void)
|
|
{
|
|
#if ENABLE_FEATURE_USE_INITTAB
|
|
FILE *file;
|
|
char buf[INIT_BUFFS_SIZE], lineAsRead[INIT_BUFFS_SIZE];
|
|
char tmpConsole[CONSOLE_BUFF_SIZE];
|
|
char *id, *runlev, *action, *command, *eol;
|
|
const struct init_action_type *a = actions;
|
|
|
|
|
|
file = fopen(INITTAB, "r");
|
|
if (file == NULL) {
|
|
/* No inittab file -- set up some default behavior */
|
|
#endif
|
|
/* Reboot on Ctrl-Alt-Del */
|
|
new_init_action(CTRLALTDEL, "/sbin/reboot", "");
|
|
/* Umount all filesystems on halt/reboot */
|
|
new_init_action(SHUTDOWN, "/bin/umount -a -r", "");
|
|
/* Swapoff on halt/reboot */
|
|
if(ENABLE_SWAPONOFF) new_init_action(SHUTDOWN, "/sbin/swapoff -a", "");
|
|
/* Prepare to restart init when a HUP is received */
|
|
new_init_action(RESTART, "/sbin/init", "");
|
|
/* Askfirst shell on tty1-4 */
|
|
new_init_action(ASKFIRST, bb_default_login_shell, "");
|
|
new_init_action(ASKFIRST, bb_default_login_shell, VC_2);
|
|
new_init_action(ASKFIRST, bb_default_login_shell, VC_3);
|
|
new_init_action(ASKFIRST, bb_default_login_shell, VC_4);
|
|
/* sysinit */
|
|
new_init_action(SYSINIT, INIT_SCRIPT, "");
|
|
|
|
return;
|
|
#if ENABLE_FEATURE_USE_INITTAB
|
|
}
|
|
|
|
while (fgets(buf, INIT_BUFFS_SIZE, file) != NULL) {
|
|
/* Skip leading spaces */
|
|
for (id = buf; *id == ' ' || *id == '\t'; id++);
|
|
|
|
/* Skip the line if it's a comment */
|
|
if (*id == '#' || *id == '\n')
|
|
continue;
|
|
|
|
/* Trim the trailing \n */
|
|
eol = strrchr(id, '\n');
|
|
if (eol != NULL)
|
|
*eol = '\0';
|
|
|
|
/* Keep a copy around for posterity's sake (and error msgs) */
|
|
strcpy(lineAsRead, buf);
|
|
|
|
/* Separate the ID field from the runlevels */
|
|
runlev = strchr(id, ':');
|
|
if (runlev == NULL || *(runlev + 1) == '\0') {
|
|
message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
|
|
continue;
|
|
} else {
|
|
*runlev = '\0';
|
|
++runlev;
|
|
}
|
|
|
|
/* Separate the runlevels from the action */
|
|
action = strchr(runlev, ':');
|
|
if (action == NULL || *(action + 1) == '\0') {
|
|
message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
|
|
continue;
|
|
} else {
|
|
*action = '\0';
|
|
++action;
|
|
}
|
|
|
|
/* Separate the action from the command */
|
|
command = strchr(action, ':');
|
|
if (command == NULL || *(command + 1) == '\0') {
|
|
message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
|
|
continue;
|
|
} else {
|
|
*command = '\0';
|
|
++command;
|
|
}
|
|
|
|
/* Ok, now process it */
|
|
for (a = actions; a->name != 0; a++) {
|
|
if (strcmp(a->name, action) == 0) {
|
|
if (*id != '\0') {
|
|
if(strncmp(id, "/dev/", 5) == 0)
|
|
id += 5;
|
|
strcpy(tmpConsole, "/dev/");
|
|
safe_strncpy(tmpConsole + 5, id,
|
|
CONSOLE_BUFF_SIZE - 5);
|
|
id = tmpConsole;
|
|
}
|
|
new_init_action(a->action, command, id);
|
|
break;
|
|
}
|
|
}
|
|
if (a->name == 0) {
|
|
/* Choke on an unknown action */
|
|
message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
|
|
}
|
|
}
|
|
fclose(file);
|
|
return;
|
|
#endif /* FEATURE_USE_INITTAB */
|
|
}
|
|
|
|
#if ENABLE_FEATURE_USE_INITTAB
|
|
static void reload_signal(int sig ATTRIBUTE_UNUSED)
|
|
{
|
|
struct init_action *a, *tmp;
|
|
|
|
message(LOG, "Reloading /etc/inittab");
|
|
|
|
/* disable old entrys */
|
|
for (a = init_action_list; a; a = a->next ) {
|
|
a->action = ONCE;
|
|
}
|
|
|
|
parse_inittab();
|
|
|
|
/* remove unused entrys */
|
|
for (a = init_action_list; a; a = tmp) {
|
|
tmp = a->next;
|
|
if (a->action & (ONCE | SYSINIT | WAIT ) &&
|
|
a->pid == 0 ) {
|
|
delete_init_action(a);
|
|
}
|
|
}
|
|
run_actions(RESPAWN);
|
|
return;
|
|
}
|
|
#endif /* FEATURE_USE_INITTAB */
|
|
|
|
int init_main(int argc, char **argv)
|
|
{
|
|
struct init_action *a;
|
|
pid_t wpid;
|
|
|
|
die_sleep = 30 * 24*60*60; /* if xmalloc will ever die... */
|
|
|
|
if (argc > 1 && !strcmp(argv[1], "-q")) {
|
|
return kill(1,SIGHUP);
|
|
}
|
|
#if !ENABLE_DEBUG_INIT
|
|
/* Expect to be invoked as init with PID=1 or be invoked as linuxrc */
|
|
if (getpid() != 1 &&
|
|
(!ENABLE_FEATURE_INITRD || !strstr(applet_name, "linuxrc")))
|
|
{
|
|
bb_show_usage();
|
|
}
|
|
/* Set up sig handlers -- be sure to
|
|
* clear all of these in run() */
|
|
signal(SIGHUP, exec_signal);
|
|
signal(SIGQUIT, exec_signal);
|
|
signal(SIGUSR1, shutdown_signal);
|
|
signal(SIGUSR2, shutdown_signal);
|
|
signal(SIGINT, ctrlaltdel_signal);
|
|
signal(SIGTERM, shutdown_signal);
|
|
signal(SIGCONT, cont_handler);
|
|
signal(SIGSTOP, stop_handler);
|
|
signal(SIGTSTP, stop_handler);
|
|
|
|
/* Turn off rebooting via CTL-ALT-DEL -- we get a
|
|
* SIGINT on CAD so we can shut things down gracefully... */
|
|
init_reboot(RB_DISABLE_CAD);
|
|
#endif
|
|
|
|
/* Figure out where the default console should be */
|
|
console_init();
|
|
|
|
/* Close whatever files are open, and reset the console. */
|
|
close(0);
|
|
close(1);
|
|
close(2);
|
|
|
|
if (device_open(console, O_RDWR | O_NOCTTY) == 0) {
|
|
set_term();
|
|
close(0);
|
|
}
|
|
|
|
chdir("/");
|
|
setsid();
|
|
{
|
|
const char * const *e;
|
|
/* Make sure environs is set to something sane */
|
|
for (e = environment; *e; e++)
|
|
putenv((char *) *e);
|
|
}
|
|
|
|
if (argc > 1) setenv("RUNLEVEL", argv[1], 1);
|
|
|
|
/* Hello world */
|
|
message(MAYBE_CONSOLE | LOG, "init started: %s", bb_msg_full_version);
|
|
|
|
/* Make sure there is enough memory to do something useful. */
|
|
if (ENABLE_SWAPONOFF) {
|
|
struct sysinfo info;
|
|
|
|
if (!sysinfo(&info) &&
|
|
(info.mem_unit ? : 1) * (long long)info.totalram < 1024*1024)
|
|
{
|
|
message(CONSOLE,"Low memory: forcing swapon.");
|
|
/* swapon -a requires /proc typically */
|
|
new_init_action(SYSINIT, "/bin/mount -t proc proc /proc", "");
|
|
/* Try to turn on swap */
|
|
new_init_action(SYSINIT, "/sbin/swapon -a", "");
|
|
run_actions(SYSINIT); /* wait and removing */
|
|
}
|
|
}
|
|
|
|
/* Check if we are supposed to be in single user mode */
|
|
if (argc > 1
|
|
&& (!strcmp(argv[1], "single") || !strcmp(argv[1], "-s") || LONE_CHAR(argv[1], '1'))
|
|
) {
|
|
/* Start a shell on console */
|
|
new_init_action(RESPAWN, bb_default_login_shell, "");
|
|
} else {
|
|
/* Not in single user mode -- see what inittab says */
|
|
|
|
/* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
|
|
* then parse_inittab() simply adds in some default
|
|
* actions(i.e., runs INIT_SCRIPT and then starts a pair
|
|
* of "askfirst" shells */
|
|
parse_inittab();
|
|
}
|
|
|
|
#if ENABLE_SELINUX
|
|
if (getenv("SELINUX_INIT") == NULL) {
|
|
int enforce = 0;
|
|
|
|
putenv("SELINUX_INIT=YES");
|
|
if (selinux_init_load_policy(&enforce) == 0) {
|
|
execv(argv[0], argv);
|
|
} else if (enforce > 0) {
|
|
/* SELinux in enforcing mode but load_policy failed */
|
|
/* At this point, we probably can't open /dev/console, so log() won't work */
|
|
message(CONSOLE,"Unable to load SELinux Policy. Machine is in enforcing mode. Halting now.");
|
|
exit(1);
|
|
}
|
|
}
|
|
#endif /* CONFIG_SELINUX */
|
|
|
|
/* Make the command line just say "init" -- thats all, nothing else */
|
|
fixup_argv(argc, argv, "init");
|
|
|
|
/* Now run everything that needs to be run */
|
|
|
|
/* First run the sysinit command */
|
|
run_actions(SYSINIT);
|
|
|
|
/* Next run anything that wants to block */
|
|
run_actions(WAIT);
|
|
|
|
/* Next run anything to be run only once */
|
|
run_actions(ONCE);
|
|
|
|
#if ENABLE_FEATURE_USE_INITTAB
|
|
/* Redefine SIGHUP to reread /etc/inittab */
|
|
signal(SIGHUP, reload_signal);
|
|
#else
|
|
signal(SIGHUP, SIG_IGN);
|
|
#endif /* FEATURE_USE_INITTAB */
|
|
|
|
|
|
/* Now run the looping stuff for the rest of forever */
|
|
while (1) {
|
|
/* run the respawn stuff */
|
|
run_actions(RESPAWN);
|
|
|
|
/* run the askfirst stuff */
|
|
run_actions(ASKFIRST);
|
|
|
|
/* Don't consume all CPU time -- sleep a bit */
|
|
sleep(1);
|
|
|
|
/* Wait for a child process to exit */
|
|
wpid = wait(NULL);
|
|
while (wpid > 0) {
|
|
/* Find out who died and clean up their corpse */
|
|
for (a = init_action_list; a; a = a->next) {
|
|
if (a->pid == wpid) {
|
|
/* Set the pid to 0 so that the process gets
|
|
* restarted by run_actions() */
|
|
a->pid = 0;
|
|
message(LOG, "Process '%s' (pid %d) exited. "
|
|
"Scheduling it for restart.",
|
|
a->command, wpid);
|
|
}
|
|
}
|
|
/* see if anyone else is waiting to be reaped */
|
|
wpid = waitpid(-1, NULL, WNOHANG);
|
|
}
|
|
}
|
|
}
|