int main(int argc, char*argv[]) {
if (argc != 2) {
log_error("This program requires one argument.");
return EXIT_FAILURE;
}
log_set_target(LOG_TARGET_AUTO);
log_parse_environment();
log_open();
umask(0022);
mac_selinux_init(NULL);
if (streq(argv[1], "start")) {
int r = 0;
if (unlink("/run/nologin") < 0 && errno != ENOENT) {
log_error_errno(errno, "Failed to remove /run/nologin file: %m");
r = -errno;
}
if (unlink("/etc/nologin") < 0 && errno != ENOENT) {
/* If the file doesn't exist and /etc simply
* was read-only (in which case unlink()
* returns EROFS even if the file doesn't
* exist), don't complain */
if (errno != EROFS || access("/etc/nologin", F_OK) >= 0) {
log_error_errno(errno, "Failed to remove /etc/nologin file: %m");
return EXIT_FAILURE;
}
}
if (r < 0)
return EXIT_FAILURE;
} else if (streq(argv[1], "stop")) {
int r;
r = write_string_file_atomic_label("/run/nologin", "System is going down.");
if (r < 0) {
log_error_errno(r, "Failed to create /run/nologin: %m");
return EXIT_FAILURE;
}
} else {
log_error("Unknown verb %s.", argv[1]);
return EXIT_FAILURE;
}
mac_selinux_finish();
return EXIT_SUCCESS;
}
static int context_write_data_static_hostname(Context *c) {
assert(c);
if (isempty(c->data[PROP_STATIC_HOSTNAME])) {
if (unlink("/etc/hostname") < 0)
return errno == ENOENT ? 0 : -errno;
return 0;
}
return write_string_file_atomic_label("/etc/hostname", c->data[PROP_STATIC_HOSTNAME]);
}
int create_shutdown_run_nologin_or_warn(void) {
int r;
/* This is used twice: once in systemd-user-sessions.service, in order to block logins when we actually go
* down, and once in systemd-logind.service when shutdowns are scheduled, and logins are to be turned off a bit
* in advance. We use the same wording of the message in both cases. */
r = write_string_file_atomic_label("/run/nologin",
"System is going down. Unprivileged users are not permitted to log in anymore. "
"For technical details, see pam_nologin(8).");
if (r < 0)
return log_error_errno(r, "Failed to create /run/nologin: %m");
return 0;
}
int write_drop_in(const char *dir, const char *unit, unsigned level,
const char *name, const char *data) {
_cleanup_free_ char *p = NULL, *q = NULL;
int r;
assert(dir);
assert(unit);
assert(name);
assert(data);
r = drop_in_file(dir, unit, level, name, &p, &q);
if (r < 0)
return r;
(void) mkdir_p(p, 0755);
return write_string_file_atomic_label(q, data);
}
