src/userdb/userdbd.c

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2
   3 #include <sys/stat.h>
   4 #include <sys/types.h>
   5
   6 #include "daemon-util.h"
   7 #include "userdbd-manager.h"
   8 #include "log.h"
   9 #include "main-func.h"
  10 #include "signal-util.h"
  11
  12 /* This service offers two Varlink services, both implementing io.systemd.UserDatabase:
  13  *
  14  *         → io.systemd.NameServiceSwitch: this is a compatibility interface for glibc NSS: it responds to
  15  *           name lookups by checking the classic NSS interfaces and responding that.
  16  *
  17  *         → io.systemd.Multiplexer: this multiplexes lookup requests to all Varlink services that have a
  18  *           socket in /run/systemd/userdb/. It's supposed to simplify clients that don't want to implement
  19  *           the full iterative logic on their own.
  20  *
  21  *         → io.systemd.DropIn: this makes JSON user/group records dropped into /run/userdb/ available as
  22  *           regular users.
  23  */
  24
  25 static int run(int argc, char *argv[]) {
  26         _cleanup_(manager_freep) Manager *m = NULL;
  27         _unused_ _cleanup_(notify_on_cleanup) const char *notify_stop = NULL;
  28         int r;
  29
  30         log_setup();
  31
  32         umask(0022);
  33
  34         if (argc != 1)
  35                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "This program takes no arguments.");
  36
  37         if (setenv("SYSTEMD_BYPASS_USERDB", "io.systemd.NameServiceSwitch:io.systemd.Multiplexer:io.systemd.DropIn", 1) < 0)
  38                 return log_error_errno(errno, "Failed to set $SYSTEMD_BYPASS_USERDB: %m");
  39
  40         assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGCHLD) >= 0);
  41
  42         r = manager_new(&m);
  43         if (r < 0)
  44                 return log_error_errno(r, "Could not create manager: %m");
  45
  46         r = manager_startup(m);
  47         if (r < 0)
  48                 return log_error_errno(r, "Failed to start up daemon: %m");
  49
  50         notify_stop = notify_start(NOTIFY_READY, NOTIFY_STOPPING);
  51
  52         r = sd_event_loop(m->event);
  53         if (r < 0)
  54                 return log_error_errno(r, "Event loop failed: %m");
  55
  56         return 0;
  57 }
  58
  59 DEFINE_MAIN_FUNCTION(run);