#include <errno.h>

#include <getopt.h>

#include <linux/reboot.h>

#include <signal.h>

#include <stdbool.h>

#include <stdlib.h>

#include <sys/mman.h>

#include <sys/mount.h>

#include <sys/reboot.h>

#include <sys/stat.h>

#include <unistd.h>

#include "cgroup-util.h"

#include "def.h"

#include "fileio.h"

#include "killall.h"

#include "log.h"

#include "missing.h"

#include "parse-util.h"

#include "process-util.h"

#include "string-util.h"

#include "switch-root.h"

#include "terminal-util.h"

#include "umount.h"

#include "util.h"

#include "virt.h"

#include "watchdog.h"

#define FINALIZE_ATTEMPTS 50

static char* arg_verb;

static uint8_t arg_exit_code;

static int parse_argv(int argc, char *argv[]) {

enum {

ARG_LOG_LEVEL = 0x100,

ARG_LOG_TARGET,

ARG_LOG_COLOR,

ARG_LOG_LOCATION,

ARG_EXIT_CODE,

};

static const struct option options[] = {

{ "log-level", required_argument, NULL, ARG_LOG_LEVEL },

{ "log-target", required_argument, NULL, ARG_LOG_TARGET },

{ "log-color", optional_argument, NULL, ARG_LOG_COLOR },

{ "log-location", optional_argument, NULL, ARG_LOG_LOCATION },

{ "exit-code", required_argument, NULL, ARG_EXIT_CODE },

{}

};

int c, r;

assert(argc >= 1);

assert(argv);

/* "-" prevents getopt from permuting argv[] and moving the verb away

while ((c = getopt_long(argc, argv, "-", options, NULL)) >= 0)

switch (c) {

case ARG_LOG_LEVEL:

r = log_set_max_level_from_string(optarg);

if (r < 0)

log_error("Failed to parse log level %s, ignoring.", optarg);

break;

case ARG_LOG_TARGET:

r = log_set_target_from_string(optarg);

if (r < 0)

log_error("Failed to parse log target %s, ignoring", optarg);

break;

case ARG_LOG_COLOR:

if (optarg) {

r = log_show_color_from_string(optarg);

if (r < 0)

log_error("Failed to parse log color setting %s, ignoring", optarg);

} else

log_show_color(true);

break;

case ARG_LOG_LOCATION:

if (optarg) {

r = log_show_location_from_string(optarg);

if (r < 0)

log_error("Failed to parse log location setting %s, ignoring", optarg);

} else

log_show_location(true);

break;

case ARG_EXIT_CODE:

r = safe_atou8(optarg, &arg_exit_code);

if (r < 0)

log_error("Failed to parse exit code %s, ignoring", optarg);

break;

case '\001':

if (!arg_verb)

arg_verb = optarg;

else

log_error("Excess arguments, ignoring");

break;

case '?':

return -EINVAL;

default:

assert_not_reached("Unhandled option code.");

}

if (!arg_verb) {

log_error("Verb argument missing.");

return -EINVAL;

}

return 0;

}

static int switch_root_initramfs(void) {

if (mount("/run/initramfs", "/run/initramfs", NULL, MS_BIND, NULL) < 0)

return log_error_errno(errno, "Failed to mount bind /run/initramfs on /run/initramfs: %m");

if (mount(NULL, "/run/initramfs", NULL, MS_PRIVATE, NULL) < 0)

return log_error_errno(errno, "Failed to make /run/initramfs private mount: %m");

/* switch_root with MS_BIND, because there might still be processes lurking around, which have open file descriptors.

return switch_root("/run/initramfs", "/oldroot", false, MS_BIND);

}

int main(int argc, char *argv[]) {

bool need_umount, need_swapoff, need_loop_detach, need_dm_detach;

bool in_container, use_watchdog = false;

_cleanup_free_ char *cgroup = NULL;

char *arguments[3];

unsigned retries;

int cmd, r;

static const char* const dirs[] = {SYSTEM_SHUTDOWN_PATH, NULL};

log_parse_environment();

r = parse_argv(argc, argv);

if (r < 0)

goto error;

/* journald will die if not gone yet. The log target defaults

log_close_console(); /* force reopen of /dev/console */

log_open();

umask(0022);

if (getpid() != 1) {

log_error("Not executed by init (PID 1).");

r = -EPERM;

goto error;

}

if (streq(arg_verb, "reboot"))

cmd = RB_AUTOBOOT;

else if (streq(arg_verb, "poweroff"))

cmd = RB_POWER_OFF;

else if (streq(arg_verb, "halt"))

cmd = RB_HALT_SYSTEM;

else if (streq(arg_verb, "kexec"))

cmd = LINUX_REBOOT_CMD_KEXEC;

else if (streq(arg_verb, "exit"))

cmd = 0; /* ignored, just checking that arg_verb is valid */

else {

r = -EINVAL;

log_error("Unknown action '%s'.", arg_verb);

goto error;

}

cg_get_root_path(&cgroup);

use_watchdog = !!getenv("WATCHDOG_USEC");

/* lock us into memory */

mlockall(MCL_CURRENT|MCL_FUTURE);

log_info("Sending SIGTERM to remaining processes...");

broadcast_signal(SIGTERM, true, true);

log_info("Sending SIGKILL to remaining processes...");

broadcast_signal(SIGKILL, true, false);

in_container = detect_container() > 0;

need_umount = !in_container;

need_swapoff = !in_container;

need_loop_detach = !in_container;

need_dm_detach = !in_container;

/* Unmount all mountpoints, swaps, and loopback devices */

for (retries = 0; retries < FINALIZE_ATTEMPTS; retries++) {

bool changed = false;

if (use_watchdog)

watchdog_ping();

/* Let's trim the cgroup tree on each iteration so

if (cgroup)

cg_trim(SYSTEMD_CGROUP_CONTROLLER, cgroup, false);

if (need_umount) {

log_info("Unmounting file systems.");

r = umount_all(&changed);

if (r == 0) {

need_umount = false;

log_info("All filesystems unmounted.");

} else if (r > 0)

log_info("Not all file systems unmounted, %d left.", r);

else

log_error_errno(r, "Failed to unmount file systems: %m");

}

if (need_swapoff) {

log_info("Deactivating swaps.");

r = swapoff_all(&changed);

if (r == 0) {

need_swapoff = false;

log_info("All swaps deactivated.");

} else if (r > 0)

log_info("Not all swaps deactivated, %d left.", r);

else

log_error_errno(r, "Failed to deactivate swaps: %m");

}

if (need_loop_detach) {

log_info("Detaching loop devices.");

r = loopback_detach_all(&changed);

if (r == 0) {

need_loop_detach = false;

log_info("All loop devices detached.");

} else if (r > 0)

log_info("Not all loop devices detached, %d left.", r);

else

log_error_errno(r, "Failed to detach loop devices: %m");

}

if (need_dm_detach) {

log_info("Detaching DM devices.");

r = dm_detach_all(&changed);

if (r == 0) {

need_dm_detach = false;

log_info("All DM devices detached.");

} else if (r > 0)

log_info("Not all DM devices detached, %d left.", r);

else

log_error_errno(r, "Failed to detach DM devices: %m");

}

if (!need_umount && !need_swapoff && !need_loop_detach && !need_dm_detach) {

if (retries > 0)

log_info("All filesystems, swaps, loop devices, DM devices detached.");

/* Yay, done */

goto initrd_jump;

}

/* If in this iteration we didn't manage to

if (!changed) {

log_info("Cannot finalize remaining%s%s%s%s continuing.",

need_umount ? " file systems," : "",

need_swapoff ? " swap devices," : "",

need_loop_detach ? " loop devices," : "",

need_dm_detach ? " DM devices," : "");

goto initrd_jump;

}

log_debug("After %u retries, couldn't finalize remaining %s%s%s%s trying again.",

retries + 1,

need_umount ? " file systems," : "",

need_swapoff ? " swap devices," : "",

need_loop_detach ? " loop devices," : "",

need_dm_detach ? " DM devices," : "");

}

log_error("Too many iterations, giving up.");

initrd_jump:

arguments[0] = NULL;

arguments[1] = arg_verb;

arguments[2] = NULL;

execute_directories(dirs, DEFAULT_TIMEOUT_USEC, arguments);

if (!in_container && !in_initrd() &&

access("/run/initramfs/shutdown", X_OK) == 0) {

r = switch_root_initramfs();

if (r >= 0) {

argv[0] = (char*) "/shutdown";

setsid();

make_console_stdio();

log_info("Successfully changed into root pivot.\n"

"Returning to initrd...");

execv("/shutdown", argv);

log_error_errno(errno, "Failed to execute shutdown binary: %m");

} else

log_error_errno(r, "Failed to switch root to \"/run/initramfs\": %m");

}

if (need_umount || need_swapoff || need_loop_detach || need_dm_detach)

log_error("Failed to finalize %s%s%s%s ignoring",

need_umount ? " file systems," : "",

need_swapoff ? " swap devices," : "",

need_loop_detach ? " loop devices," : "",

need_dm_detach ? " DM devices," : "");

/* The kernel will automaticall flush ATA disks and suchlike

if (!in_container)

sync();

if (streq(arg_verb, "exit")) {

if (in_container)

exit(arg_exit_code);

else {

/* We cannot exit() on the host, fallback on another

cmd = RB_POWER_OFF;

}

}

switch (cmd) {

case LINUX_REBOOT_CMD_KEXEC:

if (!in_container) {

/* We cheat and exec kexec to avoid doing all its work */

pid_t pid;

log_info("Rebooting with kexec.");

pid = fork();

if (pid < 0)

log_error_errno(errno, "Failed to fork: %m");

else if (pid == 0) {

const char * const args[] = {

KEXEC, "-e", NULL

};

/* Child */

execv(args[0], (char * const *) args);

_exit(EXIT_FAILURE);

} else

wait_for_terminate_and_warn("kexec", pid, true);

}

cmd = RB_AUTOBOOT;

/* Fall through */

case RB_AUTOBOOT:

if (!in_container) {

_cleanup_free_ char *param = NULL;

if (read_one_line_file(REBOOT_PARAM_FILE, &param) >= 0) {

log_info("Rebooting with argument '%s'.", param);

syscall(SYS_reboot, LINUX_REBOOT_MAGIC1, LINUX_REBOOT_MAGIC2, LINUX_REBOOT_CMD_RESTART2, param);

}

}

log_info("Rebooting.");

break;

case RB_POWER_OFF:

log_info("Powering off.");

break;

case RB_HALT_SYSTEM:

log_info("Halting system.");

break;

default:

assert_not_reached("Unknown magic");

}

reboot(cmd);

if (errno == EPERM && in_container) {

/* If we are in a container, and we lacked

log_info("Exiting container.");

exit(0);

}

r = log_error_errno(errno, "Failed to invoke reboot(): %m");

error:

log_emergency_errno(r, "Critical error while doing system shutdown: %m");

freeze();

}