#include <dbus/dbus.h>

#include <stdio.h>

#include <errno.h>

#include <string.h>

#include <unistd.h>

#include <sys/types.h>

#include <sys/stat.h>

#include <getopt.h>

#include <signal.h>

#include <sys/wait.h>

#include <fcntl.h>

#include "manager.h"

#include "log.h"

#include "mount-setup.h"

#include "hostname-setup.h"

#include "loopback-setup.h"

#include "load-fragment.h"

#include "fdset.h"

static enum {

ACTION_RUN,

ACTION_HELP,

ACTION_TEST,

ACTION_DUMP_CONFIGURATION_ITEMS

} action = ACTION_RUN;

static char *default_unit = NULL;

static ManagerRunningAs running_as = _MANAGER_RUNNING_AS_INVALID;

static bool dump_core = true;

static bool crash_shell = false;

static int crash_chvt = -1;

static bool confirm_spawn = false;

static FILE* serialization = NULL;

_noreturn static void freeze(void) {

for (;;)

pause();

}

static void nop_handler(int sig) {

}

_noreturn static void crash(int sig) {

if (!dump_core)

log_error("Caught <%s>, not dumping core.", strsignal(sig));

else {

struct sigaction sa;

pid_t pid;

/* We want to wait for the core process, hence let's enable SIGCHLD */

zero(sa);

sa.sa_handler = nop_handler;

sa.sa_flags = SA_NOCLDSTOP|SA_RESTART;

assert_se(sigaction(SIGCHLD, &sa, NULL) == 0);

if ((pid = fork()) < 0)

log_error("Caught <%s>, cannot fork for core dump: %s", strsignal(sig), strerror(errno));

else if (pid == 0) {

struct rlimit rl;

/* Enable default signal handler for core dump */

zero(sa);

sa.sa_handler = SIG_DFL;

assert_se(sigaction(sig, &sa, NULL) == 0);

/* Don't limit the core dump size */

zero(rl);

rl.rlim_cur = RLIM_INFINITY;

rl.rlim_max = RLIM_INFINITY;

setrlimit(RLIMIT_CORE, &rl);

/* Just to be sure... */

assert_se(chdir("/") == 0);

/* Raise the signal again */

raise(sig);

assert_not_reached("We shouldn't be here...");

_exit(1);

} else {

int status, r;

/* Order things nicely. */

if ((r = waitpid(pid, &status, 0)) < 0)

log_error("Caught <%s>, waitpid() failed: %s", strsignal(sig), strerror(errno));

else if (!WCOREDUMP(status))

log_error("Caught <%s>, core dump failed.", strsignal(sig));

else

log_error("Caught <%s>, dumped core as pid %llu.", strsignal(sig), (unsigned long long) pid);

}

}

if (crash_chvt)

chvt(crash_chvt);

if (crash_shell) {

struct sigaction sa;

pid_t pid;

log_info("Executing crash shell in 10s...");

sleep(10);

/* Let the kernel reap children for us */

zero(sa);

sa.sa_handler = SIG_IGN;

sa.sa_flags = SA_NOCLDSTOP|SA_NOCLDWAIT|SA_RESTART;

assert_se(sigaction(SIGCHLD, &sa, NULL) == 0);

if ((pid = fork()) < 0)

log_error("Failed to fork off crash shell: %s", strerror(errno));

else if (pid == 0) {

int fd, r;

if ((fd = acquire_terminal("/dev/console", false, true)) < 0) {

log_error("Failed to acquire terminal: %s", strerror(-fd));

_exit(1);

}

if ((r = make_stdio(fd)) < 0) {

log_error("Failed to duplicate terminal fd: %s", strerror(-r));

_exit(1);

}

execl("/bin/sh", "/bin/sh", NULL);

log_error("execl() failed: %s", strerror(errno));

_exit(1);

}

log_info("Successfully spawned crash shall as pid %llu.", (unsigned long long) pid);

}

log_info("Freezing execution.");

freeze();

}

static void install_crash_handler(void) {

struct sigaction sa;

zero(sa);

sa.sa_handler = crash;

sa.sa_flags = SA_NODEFER;

assert_se(sigaction(SIGSEGV, &sa, NULL) == 0);

assert_se(sigaction(SIGILL, &sa, NULL) == 0);

assert_se(sigaction(SIGFPE, &sa, NULL) == 0);

assert_se(sigaction(SIGBUS, &sa, NULL) == 0);

assert_se(sigaction(SIGQUIT, &sa, NULL) == 0);

assert_se(sigaction(SIGABRT, &sa, NULL) == 0);

}

static int make_null_stdio(void) {

int null_fd, r;

if ((null_fd = open("/dev/null", O_RDWR)) < 0) {

log_error("Failed to open /dev/null: %m");

return -errno;

}

if ((r = make_stdio(null_fd)) < 0)

log_warning("Failed to dup2() device: %s", strerror(-r));

return r;

}

static int console_setup(bool do_reset) {

int tty_fd, r;

/* If we are init, we connect stdin/stdout/stderr to /dev/null

release_terminal();

if (!do_reset)

return 0;

if ((tty_fd = open_terminal("/dev/console", O_WRONLY|O_NOCTTY|O_CLOEXEC)) < 0) {

log_error("Failed to open /dev/console: %s", strerror(-tty_fd));

return -tty_fd;

}

if ((r = reset_terminal(tty_fd)) < 0)

log_error("Failed to reset /dev/console: %s", strerror(-r));

close_nointr_nofail(tty_fd);

return r;

}

static int set_default_unit(const char *u) {

char *c;

assert(u);

if (!(c = strdup(u)))

return -ENOMEM;

free(default_unit);

default_unit = c;

return 0;

}

static int parse_proc_cmdline_word(const char *word) {

static const char * const rlmap[] = {

"single", SPECIAL_RUNLEVEL1_TARGET,

"-s", SPECIAL_RUNLEVEL1_TARGET,

"s", SPECIAL_RUNLEVEL1_TARGET,

"S", SPECIAL_RUNLEVEL1_TARGET,

"1", SPECIAL_RUNLEVEL1_TARGET,

"2", SPECIAL_RUNLEVEL2_TARGET,

"3", SPECIAL_RUNLEVEL3_TARGET,

"4", SPECIAL_RUNLEVEL4_TARGET,

"5", SPECIAL_RUNLEVEL5_TARGET

};

if (startswith(word, "systemd.default="))

return set_default_unit(word + 16);

else if (startswith(word, "systemd.log_target=")) {

if (log_set_target_from_string(word + 19) < 0)

log_warning("Failed to parse log target %s. Ignoring.", word + 19);

} else if (startswith(word, "systemd.log_level=")) {

if (log_set_max_level_from_string(word + 18) < 0)

log_warning("Failed to parse log level %s. Ignoring.", word + 18);

} else if (startswith(word, "systemd.dump_core=")) {

int r;

if ((r = parse_boolean(word + 18)) < 0)

log_warning("Failed to parse dump core switch %s, Ignoring.", word + 18);

else

dump_core = r;

} else if (startswith(word, "systemd.crash_shell=")) {

int r;

if ((r = parse_boolean(word + 20)) < 0)

log_warning("Failed to parse crash shell switch %s, Ignoring.", word + 20);

else

crash_shell = r;

} else if (startswith(word, "systemd.confirm_spawn=")) {

int r;

if ((r = parse_boolean(word + 22)) < 0)

log_warning("Failed to parse confirm spawn switch %s, Ignoring.", word + 22);

else

confirm_spawn = r;

} else if (startswith(word, "systemd.crash_chvt=")) {

int k;

if (safe_atoi(word + 19, &k) < 0)

log_warning("Failed to parse crash chvt switch %s, Ignoring.", word + 19);

else

crash_chvt = k;

} else if (startswith(word, "systemd.")) {

log_warning("Unknown kernel switch %s. Ignoring.", word);

log_info("Supported kernel switches:");

log_info("systemd.default=UNIT Default unit to start");

log_info("systemd.log_target=console|kmsg|syslog Log target");

log_info("systemd.log_level=LEVEL Log level");

log_info("systemd.dump_core=0|1 Dump core on crash");

log_info("systemd.crash_shell=0|1 On crash run shell");

log_info("systemd.crash_chvt=N Change to VT #N on crash");

log_info("systemd.confirm_spawn=0|1 Confirm every process spawn");

} else {

unsigned i;

/* SysV compatibility */

for (i = 0; i < ELEMENTSOF(rlmap); i += 2)

if (streq(word, rlmap[i]))

return set_default_unit(rlmap[i+1]);

}

return 0;

}

static int parse_proc_cmdline(void) {

char *line;

int r;

char *w;

size_t l;

char *state;

if ((r = read_one_line_file("/proc/cmdline", &line)) < 0) {

log_warning("Failed to read /proc/cmdline, ignoring: %s", strerror(errno));

return 0;

}

FOREACH_WORD_QUOTED(w, l, line, state) {

char *word;

if (!(word = strndup(w, l))) {

r = -ENOMEM;

goto finish;

}

r = parse_proc_cmdline_word(word);

free(word);

if (r < 0)

goto finish;

}

r = 0;

finish:

free(line);

return r;

}

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

enum {

ARG_LOG_LEVEL = 0x100,

ARG_LOG_TARGET,

ARG_DEFAULT,

ARG_RUNNING_AS,

ARG_TEST,

ARG_DUMP_CONFIGURATION_ITEMS,

ARG_CONFIRM_SPAWN,

ARG_DESERIALIZE

};

static const struct option options[] = {

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

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

{ "default", required_argument, NULL, ARG_DEFAULT },

{ "running-as", required_argument, NULL, ARG_RUNNING_AS },

{ "test", no_argument, NULL, ARG_TEST },

{ "help", no_argument, NULL, 'h' },

{ "dump-configuration-items", no_argument, NULL, ARG_DUMP_CONFIGURATION_ITEMS },

{ "confirm-spawn", no_argument, NULL, ARG_CONFIRM_SPAWN },

{ "deserialize", required_argument, NULL, ARG_DESERIALIZE },

{ NULL, 0, NULL, 0 }

};

int c, r;

assert(argc >= 1);

assert(argv);

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

switch (c) {

case ARG_LOG_LEVEL:

if ((r = log_set_max_level_from_string(optarg)) < 0) {

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

return r;

}

break;

case ARG_LOG_TARGET:

if ((r = log_set_target_from_string(optarg)) < 0) {

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

return r;

}

break;

case ARG_DEFAULT:

if ((r = set_default_unit(optarg)) < 0) {

log_error("Failed to set default unit %s: %s", optarg, strerror(-r));

return r;

}

break;

case ARG_RUNNING_AS: {

ManagerRunningAs as;

if ((as = manager_running_as_from_string(optarg)) < 0) {

log_error("Failed to parse running as value %s", optarg);

return -EINVAL;

}

running_as = as;

break;

}

case ARG_TEST:

action = ACTION_TEST;

break;

case ARG_DUMP_CONFIGURATION_ITEMS:

action = ACTION_DUMP_CONFIGURATION_ITEMS;

break;

case ARG_CONFIRM_SPAWN:

confirm_spawn = true;

break;

case ARG_DESERIALIZE: {

int fd;

FILE *f;

if ((r = safe_atoi(optarg, &fd)) < 0 || fd < 0) {

log_error("Failed to parse deserialize option %s.", optarg);

return r;

}

if (!(f = fdopen(fd, "r"))) {

log_error("Failed to open serialization fd: %m");

return r;

}

if (serialization)

fclose(serialization);

serialization = f;

break;

}

case 'h':

action = ACTION_HELP;

break;

case '?':

return -EINVAL;

default:

log_error("Unknown option code %c", c);

return -EINVAL;

}

/* PID 1 will get the kernel arguments as parameters, which we

if (running_as != MANAGER_INIT && optind < argc) {

log_error("Excess arguments.");

return -EINVAL;

}

return 0;

}

static int help(void) {

printf("%s [options]\n\n"

" -h --help Show this help\n"

" --default=UNIT Set default unit\n"

" --log-level=LEVEL Set log level\n"

" --log-target=TARGET Set log target (console, syslog, kmsg, syslog-or-kmsg)\n"

" --running-as=AS Set running as (init, system, session)\n"

" --test Determine startup sequence, dump it and exit\n"

" --dump-configuration-items Dump understood unit configuration items\n"

" --confirm-spawn Ask for confirmation when spawning processes\n",

__progname);

return 0;

}

static int prepare_reexecute(Manager *m, FILE **_f, FDSet **_fds) {

FILE *f = NULL;

FDSet *fds = NULL;

int r;

assert(m);

assert(_f);

assert(_fds);

if ((r = manager_open_serialization(&f)) < 0) {

log_error("Failed to create serialization faile: %s", strerror(-r));

goto fail;

}

if (!(fds = fdset_new())) {

r = -ENOMEM;

log_error("Failed to allocate fd set: %s", strerror(-r));

goto fail;

}

if ((r = manager_serialize(m, f, fds)) < 0) {

log_error("Failed to serialize state: %s", strerror(-r));

goto fail;

}

if (fseeko(f, 0, SEEK_SET) < 0) {

log_error("Failed to rewind serialization fd: %m");

goto fail;

}

if ((r = fd_cloexec(fileno(f), false)) < 0) {

log_error("Failed to disable O_CLOEXEC for serialization: %s", strerror(-r));

goto fail;

}

if ((r = fdset_cloexec(fds, false)) < 0) {

log_error("Failed to disable O_CLOEXEC for serialization fds: %s", strerror(-r));

goto fail;

}

*_f = f;

*_fds = fds;

return 0;

fail:

fdset_free(fds);

if (f)

fclose(f);

return r;

}

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

Manager *m = NULL;

Unit *target = NULL;

Job *job = NULL;

int r, retval = 1;

FDSet *fds = NULL;

bool reexecute = false;

if (getpid() == 1) {

running_as = MANAGER_INIT;

log_set_target(LOG_TARGET_SYSLOG_OR_KMSG);

} else

running_as = MANAGER_SESSION;

if (set_default_unit(SPECIAL_DEFAULT_TARGET) < 0)

goto finish;

/* Mount /proc, /sys and friends, so that /proc/cmdline and

if (mount_setup() < 0)

goto finish;

/* Reset all signal handlers. */

assert_se(reset_all_signal_handlers() == 0);

/* If we are init, we can block sigkill. Yay. */

ignore_signal(SIGKILL);

ignore_signal(SIGPIPE);

if (running_as != MANAGER_SESSION)

if (parse_proc_cmdline() < 0)

goto finish;

log_parse_environment();

if (parse_argv(argc, argv) < 0)

goto finish;

if (action == ACTION_HELP) {

retval = help();

goto finish;

} else if (action == ACTION_DUMP_CONFIGURATION_ITEMS) {

unit_dump_config_items(stdout);

retval = 0;

goto finish;

}

assert_se(action == ACTION_RUN || action == ACTION_TEST);

/* Remember open file descriptors for later deserialization */

if (serialization) {

if ((r = fdset_new_fill(&fds)) < 0) {

log_error("Failed to allocate fd set: %s", strerror(-r));

goto finish;

}

assert_se(fdset_remove(fds, fileno(serialization)) >= 0);

} else

close_all_fds(NULL, 0);

/* Set up PATH unless it is already set */

setenv("PATH",

"/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",

running_as == MANAGER_INIT);

/* Move out of the way, so that we won't block unmounts */

assert_se(chdir("/") == 0);

if (running_as != MANAGER_SESSION) {

/* Become a session leader if we aren't one yet. */

setsid();

/* Disable the umask logic */

umask(0);

}

/* Make sure D-Bus doesn't fiddle with the SIGPIPE handlers */

dbus_connection_set_change_sigpipe(FALSE);

/* Reset the console, but only if this is really init and we

if (running_as != MANAGER_SESSION && action == ACTION_RUN) {

console_setup(getpid() == 1 && !serialization);

make_null_stdio();

}

/* Open the logging devices, if possible and necessary */

log_open();

/* Make sure we leave a core dump without panicing the

if (getpid() == 1)

install_crash_handler();

log_debug("systemd running in %s mode.", manager_running_as_to_string(running_as));

if (running_as == MANAGER_INIT) {

hostname_setup();

loopback_setup();

}

if ((r = manager_new(running_as, confirm_spawn, &m)) < 0) {

log_error("Failed to allocate manager object: %s", strerror(-r));

goto finish;

}

if ((r = manager_startup(m, serialization, fds)) < 0)

log_error("Failed to fully start up daemon: %s", strerror(-r));

if (fds) {

/* This will close all file descriptors that were opened, but

fdset_free(fds);

fds = NULL;

}

if (serialization) {

fclose(serialization);

serialization = NULL;

} else {

log_debug("Activating default unit: %s", default_unit);

if ((r = manager_load_unit(m, default_unit, NULL, &target)) < 0) {

log_error("Failed to load default target: %s", strerror(-r));

log_info("Trying to load rescue target...");

if ((r = manager_load_unit(m, SPECIAL_RESCUE_TARGET, NULL, &target)) < 0) {

log_error("Failed to load rescue target: %s", strerror(-r));

goto finish;

}

}

if (action == ACTION_TEST) {

printf("-> By units:\n");

manager_dump_units(m, stdout, "\t");

}

if ((r = manager_add_job(m, JOB_START, target, JOB_REPLACE, false, &job)) < 0) {

log_error("Failed to start default target: %s", strerror(-r));

goto finish;

}

if (action == ACTION_TEST) {

printf("-> By jobs:\n");

manager_dump_jobs(m, stdout, "\t");

retval = 0;

goto finish;

}

}

for (;;) {

if ((r = manager_loop(m)) < 0) {

log_error("Failed to run mainloop: %s", strerror(-r));

goto finish;

}

switch (m->exit_code) {

case MANAGER_EXIT:

retval = 0;

log_debug("Exit.");

goto finish;

case MANAGER_RELOAD:

if ((r = manager_reload(m)) < 0)

log_error("Failed to reload: %s", strerror(-r));

break;

case MANAGER_REEXECUTE:

if (prepare_reexecute(m, &serialization, &fds) < 0)

goto finish;

reexecute = true;

log_debug("Reexecuting.");

goto finish;

default:

assert_not_reached("Unknown exit code.");

}

}

finish:

if (m)

manager_free(m);

free(default_unit);

dbus_shutdown();

if (reexecute) {

const char *args[11];

unsigned i = 0;

char sfd[16];

assert(serialization);

assert(fds);

args[i++] = SYSTEMD_BINARY_PATH;

args[i++] = "--log-level";

args[i++] = log_level_to_string(log_get_max_level());

args[i++] = "--log-target";

args[i++] = log_target_to_string(log_get_target());

args[i++] = "--running-as";

args[i++] = manager_running_as_to_string(running_as);

snprintf(sfd, sizeof(sfd), "%i", fileno(serialization));

char_array_0(sfd);

args[i++] = "--deserialize";

args[i++] = sfd;

if (confirm_spawn)

args[i++] = "--confirm-spawn";

args[i++] = NULL;

assert(i <= ELEMENTSOF(args));

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

log_error("Failed to reexecute: %m");

}

if (serialization)

fclose(serialization);

if (fds)

fdset_free(fds);

if (getpid() == 1)

freeze();

return retval;

}