1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
2 
3 #include <errno.h>
4 #include <fcntl.h>
5 #include <sys/types.h>
6 #include <unistd.h>
7 
8 #include "sd-daemon.h"
9 #include "sd-device.h"
10 
11 #include "alloc-util.h"
12 #include "bus-error.h"
13 #include "bus-locator.h"
14 #include "bus-log-control-api.h"
15 #include "bus-polkit.h"
16 #include "cgroup-util.h"
17 #include "daemon-util.h"
18 #include "def.h"
19 #include "device-util.h"
20 #include "dirent-util.h"
21 #include "fd-util.h"
22 #include "format-util.h"
23 #include "fs-util.h"
24 #include "logind-dbus.h"
25 #include "logind-seat-dbus.h"
26 #include "logind-session-dbus.h"
27 #include "logind-user-dbus.h"
28 #include "logind.h"
29 #include "main-func.h"
30 #include "mkdir-label.h"
31 #include "parse-util.h"
32 #include "process-util.h"
33 #include "selinux-util.h"
34 #include "service-util.h"
35 #include "signal-util.h"
36 #include "strv.h"
37 #include "terminal-util.h"
38 #include "udev-util.h"
39 #include "user-util.h"
40 
41 static Manager* manager_unref(Manager *m);
42 DEFINE_TRIVIAL_CLEANUP_FUNC(Manager*, manager_unref);
43 
manager_new(Manager ** ret)44 static int manager_new(Manager **ret) {
45         _cleanup_(manager_unrefp) Manager *m = NULL;
46         int r;
47 
48         assert(ret);
49 
50         m = new(Manager, 1);
51         if (!m)
52                 return -ENOMEM;
53 
54         *m = (Manager) {
55                 .console_active_fd = -1,
56                 .reserve_vt_fd = -1,
57                 .enable_wall_messages = true,
58                 .idle_action_not_before_usec = now(CLOCK_MONOTONIC),
59         };
60 
61         m->devices = hashmap_new(&string_hash_ops);
62         m->seats = hashmap_new(&string_hash_ops);
63         m->sessions = hashmap_new(&string_hash_ops);
64         m->sessions_by_leader = hashmap_new(NULL);
65         m->users = hashmap_new(NULL);
66         m->inhibitors = hashmap_new(&string_hash_ops);
67         m->buttons = hashmap_new(&string_hash_ops);
68 
69         m->user_units = hashmap_new(&string_hash_ops);
70         m->session_units = hashmap_new(&string_hash_ops);
71 
72         if (!m->devices || !m->seats || !m->sessions || !m->sessions_by_leader || !m->users || !m->inhibitors || !m->buttons || !m->user_units || !m->session_units)
73                 return -ENOMEM;
74 
75         r = sd_event_default(&m->event);
76         if (r < 0)
77                 return r;
78 
79         r = sd_event_add_signal(m->event, NULL, SIGINT, NULL, NULL);
80         if (r < 0)
81                 return r;
82 
83         r = sd_event_add_signal(m->event, NULL, SIGTERM, NULL, NULL);
84         if (r < 0)
85                 return r;
86 
87         (void) sd_event_set_watchdog(m->event, true);
88 
89         manager_reset_config(m);
90 
91         *ret = TAKE_PTR(m);
92         return 0;
93 }
94 
manager_unref(Manager * m)95 static Manager* manager_unref(Manager *m) {
96         Session *session;
97         User *u;
98         Device *d;
99         Seat *s;
100         Inhibitor *i;
101         Button *b;
102 
103         if (!m)
104                 return NULL;
105 
106         while ((session = hashmap_first(m->sessions)))
107                 session_free(session);
108 
109         while ((u = hashmap_first(m->users)))
110                 user_free(u);
111 
112         while ((d = hashmap_first(m->devices)))
113                 device_free(d);
114 
115         while ((s = hashmap_first(m->seats)))
116                 seat_free(s);
117 
118         while ((i = hashmap_first(m->inhibitors)))
119                 inhibitor_free(i);
120 
121         while ((b = hashmap_first(m->buttons)))
122                 button_free(b);
123 
124         hashmap_free(m->devices);
125         hashmap_free(m->seats);
126         hashmap_free(m->sessions);
127         hashmap_free(m->sessions_by_leader);
128         hashmap_free(m->users);
129         hashmap_free(m->inhibitors);
130         hashmap_free(m->buttons);
131         hashmap_free(m->brightness_writers);
132 
133         hashmap_free(m->user_units);
134         hashmap_free(m->session_units);
135 
136         sd_event_source_unref(m->idle_action_event_source);
137         sd_event_source_unref(m->inhibit_timeout_source);
138         sd_event_source_unref(m->scheduled_shutdown_timeout_source);
139         sd_event_source_unref(m->nologin_timeout_source);
140         sd_event_source_unref(m->wall_message_timeout_source);
141 
142         sd_event_source_unref(m->console_active_event_source);
143         sd_event_source_unref(m->lid_switch_ignore_event_source);
144 
145         sd_event_source_unref(m->reboot_key_long_press_event_source);
146 
147 #if ENABLE_UTMP
148         sd_event_source_unref(m->utmp_event_source);
149 #endif
150 
151         safe_close(m->console_active_fd);
152 
153         sd_device_monitor_unref(m->device_seat_monitor);
154         sd_device_monitor_unref(m->device_monitor);
155         sd_device_monitor_unref(m->device_vcsa_monitor);
156         sd_device_monitor_unref(m->device_button_monitor);
157 
158         if (m->unlink_nologin)
159                 (void) unlink_or_warn("/run/nologin");
160 
161         bus_verify_polkit_async_registry_free(m->polkit_registry);
162 
163         sd_bus_flush_close_unref(m->bus);
164         sd_event_unref(m->event);
165 
166         safe_close(m->reserve_vt_fd);
167 
168         strv_free(m->kill_only_users);
169         strv_free(m->kill_exclude_users);
170 
171         free(m->scheduled_shutdown_tty);
172         free(m->wall_message);
173         free(m->action_job);
174 
175         strv_free(m->efi_boot_loader_entries);
176         free(m->efi_loader_entry_one_shot);
177 
178         return mfree(m);
179 }
180 
manager_enumerate_devices(Manager * m)181 static int manager_enumerate_devices(Manager *m) {
182         _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
183         sd_device *d;
184         int r;
185 
186         assert(m);
187 
188         /* Loads devices from udev and creates seats for them as
189          * necessary */
190 
191         r = sd_device_enumerator_new(&e);
192         if (r < 0)
193                 return r;
194 
195         r = sd_device_enumerator_add_match_tag(e, "master-of-seat");
196         if (r < 0)
197                 return r;
198 
199         FOREACH_DEVICE(e, d) {
200                 int k;
201 
202                 k = manager_process_seat_device(m, d);
203                 if (k < 0)
204                         r = k;
205         }
206 
207         return r;
208 }
209 
manager_enumerate_buttons(Manager * m)210 static int manager_enumerate_buttons(Manager *m) {
211         _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
212         sd_device *d;
213         int r;
214 
215         assert(m);
216 
217         /* Loads buttons from udev */
218 
219         if (manager_all_buttons_ignored(m))
220                 return 0;
221 
222         r = sd_device_enumerator_new(&e);
223         if (r < 0)
224                 return r;
225 
226         r = sd_device_enumerator_add_match_subsystem(e, "input", true);
227         if (r < 0)
228                 return r;
229 
230         r = sd_device_enumerator_add_match_tag(e, "power-switch");
231         if (r < 0)
232                 return r;
233 
234         FOREACH_DEVICE(e, d) {
235                 int k;
236 
237                 k = manager_process_button_device(m, d);
238                 if (k < 0)
239                         r = k;
240         }
241 
242         return r;
243 }
244 
manager_enumerate_seats(Manager * m)245 static int manager_enumerate_seats(Manager *m) {
246         _cleanup_closedir_ DIR *d = NULL;
247         int r = 0;
248 
249         assert(m);
250 
251         /* This loads data about seats stored on disk, but does not
252          * actually create any seats. Removes data of seats that no
253          * longer exist. */
254 
255         d = opendir("/run/systemd/seats");
256         if (!d) {
257                 if (errno == ENOENT)
258                         return 0;
259 
260                 return log_error_errno(errno, "Failed to open /run/systemd/seats: %m");
261         }
262 
263         FOREACH_DIRENT(de, d, return -errno) {
264                 Seat *s;
265                 int k;
266 
267                 if (!dirent_is_file(de))
268                         continue;
269 
270                 s = hashmap_get(m->seats, de->d_name);
271                 if (!s) {
272                         if (unlinkat(dirfd(d), de->d_name, 0) < 0)
273                                 log_warning_errno(errno, "Failed to remove /run/systemd/seats/%s, ignoring: %m",
274                                                   de->d_name);
275                         continue;
276                 }
277 
278                 k = seat_load(s);
279                 if (k < 0)
280                         r = k;
281         }
282 
283         return r;
284 }
285 
manager_enumerate_linger_users(Manager * m)286 static int manager_enumerate_linger_users(Manager *m) {
287         _cleanup_closedir_ DIR *d = NULL;
288         int r = 0;
289 
290         assert(m);
291 
292         d = opendir("/var/lib/systemd/linger");
293         if (!d) {
294                 if (errno == ENOENT)
295                         return 0;
296 
297                 return log_error_errno(errno, "Failed to open /var/lib/systemd/linger/: %m");
298         }
299 
300         FOREACH_DIRENT(de, d, return -errno) {
301                 int k;
302 
303                 if (!dirent_is_file(de))
304                         continue;
305 
306                 k = manager_add_user_by_name(m, de->d_name, NULL);
307                 if (k < 0)
308                         r = log_warning_errno(k, "Couldn't add lingering user %s, ignoring: %m", de->d_name);
309         }
310 
311         return r;
312 }
313 
manager_enumerate_users(Manager * m)314 static int manager_enumerate_users(Manager *m) {
315         _cleanup_closedir_ DIR *d = NULL;
316         int r, k;
317 
318         assert(m);
319 
320         /* Add lingering users */
321         r = manager_enumerate_linger_users(m);
322 
323         /* Read in user data stored on disk */
324         d = opendir("/run/systemd/users");
325         if (!d) {
326                 if (errno == ENOENT)
327                         return 0;
328 
329                 return log_error_errno(errno, "Failed to open /run/systemd/users: %m");
330         }
331 
332         FOREACH_DIRENT(de, d, return -errno) {
333                 User *u;
334                 uid_t uid;
335 
336                 if (!dirent_is_file(de))
337                         continue;
338 
339                 k = parse_uid(de->d_name, &uid);
340                 if (k < 0) {
341                         r = log_warning_errno(k, "Failed to parse filename /run/systemd/users/%s as UID.", de->d_name);
342                         continue;
343                 }
344 
345                 k = manager_add_user_by_uid(m, uid, &u);
346                 if (k < 0) {
347                         r = log_warning_errno(k, "Failed to add user by file name %s, ignoring: %m", de->d_name);
348                         continue;
349                 }
350 
351                 user_add_to_gc_queue(u);
352 
353                 k = user_load(u);
354                 if (k < 0)
355                         r = k;
356         }
357 
358         return r;
359 }
360 
parse_fdname(const char * fdname,char ** session_id,dev_t * dev)361 static int parse_fdname(const char *fdname, char **session_id, dev_t *dev) {
362         _cleanup_strv_free_ char **parts = NULL;
363         _cleanup_free_ char *id = NULL;
364         unsigned major, minor;
365         int r;
366 
367         parts = strv_split(fdname, "-");
368         if (!parts)
369                 return -ENOMEM;
370         if (strv_length(parts) != 5)
371                 return -EINVAL;
372 
373         if (!streq(parts[0], "session"))
374                 return -EINVAL;
375 
376         id = strdup(parts[1]);
377         if (!id)
378                 return -ENOMEM;
379 
380         if (!streq(parts[2], "device"))
381                 return -EINVAL;
382 
383         r = safe_atou(parts[3], &major);
384         if (r < 0)
385                 return r;
386         r = safe_atou(parts[4], &minor);
387         if (r < 0)
388                 return r;
389 
390         *dev = makedev(major, minor);
391         *session_id = TAKE_PTR(id);
392 
393         return 0;
394 }
395 
deliver_fd(Manager * m,const char * fdname,int fd)396 static int deliver_fd(Manager *m, const char *fdname, int fd) {
397         _cleanup_free_ char *id = NULL;
398         SessionDevice *sd;
399         struct stat st;
400         Session *s;
401         dev_t dev;
402         int r;
403 
404         assert(m);
405         assert(fd >= 0);
406 
407         r = parse_fdname(fdname, &id, &dev);
408         if (r < 0)
409                 return log_debug_errno(r, "Failed to parse fd name %s: %m", fdname);
410 
411         s = hashmap_get(m->sessions, id);
412         if (!s)
413                 /* If the session doesn't exist anymore, the associated session device attached to this fd
414                  * doesn't either. Let's simply close this fd. */
415                 return log_debug_errno(SYNTHETIC_ERRNO(ENXIO), "Failed to attach fd for unknown session: %s", id);
416 
417         if (fstat(fd, &st) < 0)
418                 /* The device is allowed to go away at a random point, in which case fstat() failing is
419                  * expected. */
420                 return log_debug_errno(errno, "Failed to stat device fd for session %s: %m", id);
421 
422         if (!S_ISCHR(st.st_mode) || st.st_rdev != dev)
423                 return log_debug_errno(SYNTHETIC_ERRNO(ENODEV), "Device fd doesn't point to the expected character device node");
424 
425         sd = hashmap_get(s->devices, &dev);
426         if (!sd)
427                 /* Weird, we got an fd for a session device which wasn't recorded in the session state
428                  * file... */
429                 return log_warning_errno(SYNTHETIC_ERRNO(ENODEV), "Got fd for missing session device [%u:%u] in session %s",
430                                          major(dev), minor(dev), s->id);
431 
432         log_debug("Attaching fd to session device [%u:%u] for session %s",
433                   major(dev), minor(dev), s->id);
434 
435         session_device_attach_fd(sd, fd, s->was_active);
436         return 0;
437 }
438 
manager_attach_fds(Manager * m)439 static int manager_attach_fds(Manager *m) {
440         _cleanup_strv_free_ char **fdnames = NULL;
441         int r, n;
442 
443         /* Upon restart, PID1 will send us back all fds of session devices that we previously opened. Each
444          * file descriptor is associated with a given session. The session ids are passed through FDNAMES. */
445 
446         n = sd_listen_fds_with_names(true, &fdnames);
447         if (n < 0)
448                 return log_warning_errno(n, "Failed to acquire passed fd list: %m");
449         if (n == 0)
450                 return 0;
451 
452         for (int i = 0; i < n; i++) {
453                 int fd = SD_LISTEN_FDS_START + i;
454 
455                 if (deliver_fd(m, fdnames[i], fd) >= 0)
456                         continue;
457 
458                 /* Hmm, we couldn't deliver the fd to any session device object? If so, let's close the fd */
459                 safe_close(fd);
460 
461                 /* Remove from fdstore as well */
462                 r = sd_notifyf(false,
463                                "FDSTOREREMOVE=1\n"
464                                "FDNAME=%s", fdnames[i]);
465                 if (r < 0)
466                         log_warning_errno(r, "Failed to remove file descriptor from the store, ignoring: %m");
467         }
468 
469         return 0;
470 }
471 
manager_enumerate_sessions(Manager * m)472 static int manager_enumerate_sessions(Manager *m) {
473         _cleanup_closedir_ DIR *d = NULL;
474         int r = 0, k;
475 
476         assert(m);
477 
478         /* Read in session data stored on disk */
479         d = opendir("/run/systemd/sessions");
480         if (!d) {
481                 if (errno == ENOENT)
482                         return 0;
483 
484                 return log_error_errno(errno, "Failed to open /run/systemd/sessions: %m");
485         }
486 
487         FOREACH_DIRENT(de, d, return -errno) {
488                 struct Session *s;
489 
490                 if (!dirent_is_file(de))
491                         continue;
492 
493                 k = manager_add_session(m, de->d_name, &s);
494                 if (k < 0) {
495                         r = log_warning_errno(k, "Failed to add session by file name %s, ignoring: %m", de->d_name);
496                         continue;
497                 }
498 
499                 session_add_to_gc_queue(s);
500 
501                 k = session_load(s);
502                 if (k < 0)
503                         r = k;
504         }
505 
506         /* We might be restarted and PID1 could have sent us back the session device fds we previously
507          * saved. */
508         (void) manager_attach_fds(m);
509 
510         return r;
511 }
512 
manager_enumerate_inhibitors(Manager * m)513 static int manager_enumerate_inhibitors(Manager *m) {
514         _cleanup_closedir_ DIR *d = NULL;
515         int r = 0;
516 
517         assert(m);
518 
519         d = opendir("/run/systemd/inhibit");
520         if (!d) {
521                 if (errno == ENOENT)
522                         return 0;
523 
524                 return log_error_errno(errno, "Failed to open /run/systemd/inhibit: %m");
525         }
526 
527         FOREACH_DIRENT(de, d, return -errno) {
528                 int k;
529                 Inhibitor *i;
530 
531                 if (!dirent_is_file(de))
532                         continue;
533 
534                 k = manager_add_inhibitor(m, de->d_name, &i);
535                 if (k < 0) {
536                         r = log_warning_errno(k, "Couldn't add inhibitor %s, ignoring: %m", de->d_name);
537                         continue;
538                 }
539 
540                 k = inhibitor_load(i);
541                 if (k < 0)
542                         r = k;
543         }
544 
545         return r;
546 }
547 
manager_dispatch_seat_udev(sd_device_monitor * monitor,sd_device * device,void * userdata)548 static int manager_dispatch_seat_udev(sd_device_monitor *monitor, sd_device *device, void *userdata) {
549         Manager *m = userdata;
550 
551         assert(m);
552         assert(device);
553 
554         manager_process_seat_device(m, device);
555         return 0;
556 }
557 
manager_dispatch_device_udev(sd_device_monitor * monitor,sd_device * device,void * userdata)558 static int manager_dispatch_device_udev(sd_device_monitor *monitor, sd_device *device, void *userdata) {
559         Manager *m = userdata;
560 
561         assert(m);
562         assert(device);
563 
564         manager_process_seat_device(m, device);
565         return 0;
566 }
567 
manager_dispatch_vcsa_udev(sd_device_monitor * monitor,sd_device * device,void * userdata)568 static int manager_dispatch_vcsa_udev(sd_device_monitor *monitor, sd_device *device, void *userdata) {
569         Manager *m = userdata;
570         const char *name;
571 
572         assert(m);
573         assert(device);
574 
575         /* Whenever a VCSA device is removed try to reallocate our
576          * VTs, to make sure our auto VTs never go away. */
577 
578         if (sd_device_get_sysname(device, &name) >= 0 &&
579             startswith(name, "vcsa") &&
580             device_for_action(device, SD_DEVICE_REMOVE))
581                 seat_preallocate_vts(m->seat0);
582 
583         return 0;
584 }
585 
manager_dispatch_button_udev(sd_device_monitor * monitor,sd_device * device,void * userdata)586 static int manager_dispatch_button_udev(sd_device_monitor *monitor, sd_device *device, void *userdata) {
587         Manager *m = userdata;
588 
589         assert(m);
590         assert(device);
591 
592         manager_process_button_device(m, device);
593         return 0;
594 }
595 
manager_dispatch_console(sd_event_source * s,int fd,uint32_t revents,void * userdata)596 static int manager_dispatch_console(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
597         Manager *m = userdata;
598 
599         assert(m);
600         assert(m->seat0);
601         assert(m->console_active_fd == fd);
602 
603         seat_read_active_vt(m->seat0);
604         return 0;
605 }
606 
manager_reserve_vt(Manager * m)607 static int manager_reserve_vt(Manager *m) {
608         _cleanup_free_ char *p = NULL;
609 
610         assert(m);
611 
612         if (m->reserve_vt <= 0)
613                 return 0;
614 
615         if (asprintf(&p, "/dev/tty%u", m->reserve_vt) < 0)
616                 return log_oom();
617 
618         m->reserve_vt_fd = open(p, O_RDWR|O_NOCTTY|O_CLOEXEC|O_NONBLOCK);
619         if (m->reserve_vt_fd < 0) {
620 
621                 /* Don't complain on VT-less systems */
622                 if (errno != ENOENT)
623                         log_warning_errno(errno, "Failed to pin reserved VT: %m");
624                 return -errno;
625         }
626 
627         return 0;
628 }
629 
manager_connect_bus(Manager * m)630 static int manager_connect_bus(Manager *m) {
631         int r;
632 
633         assert(m);
634         assert(!m->bus);
635 
636         r = sd_bus_default_system(&m->bus);
637         if (r < 0)
638                 return log_error_errno(r, "Failed to connect to system bus: %m");
639 
640         r = bus_add_implementation(m->bus, &manager_object, m);
641         if (r < 0)
642                 return r;
643 
644         r = bus_log_control_api_register(m->bus);
645         if (r < 0)
646                 return r;
647 
648         r = bus_match_signal_async(m->bus, NULL, bus_systemd_mgr, "JobRemoved", match_job_removed, NULL, m);
649         if (r < 0)
650                 return log_error_errno(r, "Failed to request match for JobRemoved: %m");
651 
652         r = bus_match_signal_async(m->bus, NULL, bus_systemd_mgr, "UnitRemoved", match_unit_removed, NULL, m);
653         if (r < 0)
654                 return log_error_errno(r, "Failed to request match for UnitRemoved: %m");
655 
656         r = sd_bus_match_signal_async(
657                         m->bus,
658                         NULL,
659                         "org.freedesktop.systemd1",
660                         NULL,
661                         "org.freedesktop.DBus.Properties",
662                         "PropertiesChanged",
663                         match_properties_changed, NULL, m);
664         if (r < 0)
665                 return log_error_errno(r, "Failed to request match for PropertiesChanged: %m");
666 
667         r = bus_match_signal_async(m->bus, NULL, bus_systemd_mgr, "Reloading", match_reloading, NULL, m);
668         if (r < 0)
669                 return log_error_errno(r, "Failed to request match for Reloading: %m");
670 
671         r = bus_call_method_async(m->bus, NULL, bus_systemd_mgr, "Subscribe", NULL, NULL, NULL);
672         if (r < 0)
673                 return log_error_errno(r, "Failed to enable subscription: %m");
674 
675         r = sd_bus_request_name_async(m->bus, NULL, "org.freedesktop.login1", 0, NULL, NULL);
676         if (r < 0)
677                 return log_error_errno(r, "Failed to request name: %m");
678 
679         r = sd_bus_attach_event(m->bus, m->event, SD_EVENT_PRIORITY_NORMAL);
680         if (r < 0)
681                 return log_error_errno(r, "Failed to attach bus to event loop: %m");
682 
683         return 0;
684 }
685 
manager_vt_switch(sd_event_source * src,const struct signalfd_siginfo * si,void * data)686 static int manager_vt_switch(sd_event_source *src, const struct signalfd_siginfo *si, void *data) {
687         Manager *m = data;
688         Session *active;
689 
690         /*
691          * We got a VT-switch signal and we have to acknowledge it immediately.
692          * Preferably, we'd just use m->seat0->active->vtfd, but unfortunately,
693          * old user-space might run multiple sessions on a single VT, *sigh*.
694          * Therefore, we have to iterate all sessions and find one with a vtfd
695          * on the requested VT.
696          * As only VTs with active controllers have VT_PROCESS set, our current
697          * notion of the active VT might be wrong (for instance if the switch
698          * happens while we setup VT_PROCESS). Therefore, read the current VT
699          * first and then use s->active->vtnr as reference. Note that this is
700          * not racy, as no further VT-switch can happen as long as we're in
701          * synchronous VT_PROCESS mode.
702          */
703 
704         assert(m->seat0);
705         seat_read_active_vt(m->seat0);
706 
707         active = m->seat0->active;
708         if (!active || active->vtnr < 1) {
709                 _cleanup_close_ int fd = -1;
710                 int r;
711 
712                 /* We are requested to acknowledge the VT-switch signal by the kernel but
713                  * there's no registered sessions for the current VT. Normally this
714                  * shouldn't happen but something wrong might have happened when we tried
715                  * to release the VT. Better be safe than sorry, and try to release the VT
716                  * one more time otherwise the user will be locked with the current VT. */
717 
718                 log_warning("Received VT_PROCESS signal without a registered session, restoring VT.");
719 
720                 /* At this point we only have the kernel mapping for referring to the
721                  * current VT. */
722                 fd = open_terminal("/dev/tty0", O_RDWR|O_NOCTTY|O_CLOEXEC|O_NONBLOCK);
723                 if (fd < 0) {
724                         log_warning_errno(fd, "Failed to open, ignoring: %m");
725                         return 0;
726                 }
727 
728                 r = vt_release(fd, true);
729                 if (r < 0)
730                         log_warning_errno(r, "Failed to release VT, ignoring: %m");
731 
732                 return 0;
733         }
734 
735         if (active->vtfd >= 0)
736                 session_leave_vt(active);
737         else
738                 LIST_FOREACH(sessions_by_seat, iter, m->seat0->sessions)
739                         if (iter->vtnr == active->vtnr && iter->vtfd >= 0) {
740                                 session_leave_vt(iter);
741                                 break;
742                         }
743 
744         return 0;
745 }
746 
manager_connect_console(Manager * m)747 static int manager_connect_console(Manager *m) {
748         int r;
749 
750         assert(m);
751         assert(m->console_active_fd < 0);
752 
753         /* On certain systems (such as S390, Xen, and containers) /dev/tty0 does not exist (as there is no VC), so
754          * don't fail if we can't open it. */
755 
756         if (access("/dev/tty0", F_OK) < 0)
757                 return 0;
758 
759         m->console_active_fd = open("/sys/class/tty/tty0/active", O_RDONLY|O_NOCTTY|O_CLOEXEC);
760         if (m->console_active_fd < 0) {
761 
762                 /* On some systems /dev/tty0 may exist even though /sys/class/tty/tty0 does not. These are broken, but
763                  * common. Let's complain but continue anyway. */
764                 if (errno == ENOENT) {
765                         log_warning_errno(errno, "System has /dev/tty0 but not /sys/class/tty/tty0/active which is broken, ignoring: %m");
766                         return 0;
767                 }
768 
769                 return log_error_errno(errno, "Failed to open /sys/class/tty/tty0/active: %m");
770         }
771 
772         r = sd_event_add_io(m->event, &m->console_active_event_source, m->console_active_fd, 0, manager_dispatch_console, m);
773         if (r < 0)
774                 return log_error_errno(r, "Failed to watch foreground console: %m");
775 
776         /*
777          * SIGRTMIN is used as global VT-release signal, SIGRTMIN + 1 is used
778          * as VT-acquire signal. We ignore any acquire-events (yes, we still
779          * have to provide a valid signal-number for it!) and acknowledge all
780          * release events immediately.
781          */
782 
783         if (SIGRTMIN + 1 > SIGRTMAX)
784                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
785                                        "Not enough real-time signals available: %u-%u",
786                                        SIGRTMIN, SIGRTMAX);
787 
788         assert_se(ignore_signals(SIGRTMIN + 1) >= 0);
789         assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGRTMIN, -1) >= 0);
790 
791         r = sd_event_add_signal(m->event, NULL, SIGRTMIN, manager_vt_switch, m);
792         if (r < 0)
793                 return log_error_errno(r, "Failed to subscribe to signal: %m");
794 
795         return 0;
796 }
797 
manager_connect_udev(Manager * m)798 static int manager_connect_udev(Manager *m) {
799         int r;
800 
801         assert(m);
802         assert(!m->device_seat_monitor);
803         assert(!m->device_monitor);
804         assert(!m->device_vcsa_monitor);
805         assert(!m->device_button_monitor);
806 
807         r = sd_device_monitor_new(&m->device_seat_monitor);
808         if (r < 0)
809                 return r;
810 
811         r = sd_device_monitor_filter_add_match_tag(m->device_seat_monitor, "master-of-seat");
812         if (r < 0)
813                 return r;
814 
815         r = sd_device_monitor_attach_event(m->device_seat_monitor, m->event);
816         if (r < 0)
817                 return r;
818 
819         r = sd_device_monitor_start(m->device_seat_monitor, manager_dispatch_seat_udev, m);
820         if (r < 0)
821                 return r;
822 
823         (void) sd_event_source_set_description(sd_device_monitor_get_event_source(m->device_seat_monitor), "logind-seat-monitor");
824 
825         r = sd_device_monitor_new(&m->device_monitor);
826         if (r < 0)
827                 return r;
828 
829         r = sd_device_monitor_filter_add_match_subsystem_devtype(m->device_monitor, "input", NULL);
830         if (r < 0)
831                 return r;
832 
833         r = sd_device_monitor_filter_add_match_subsystem_devtype(m->device_monitor, "graphics", NULL);
834         if (r < 0)
835                 return r;
836 
837         r = sd_device_monitor_filter_add_match_subsystem_devtype(m->device_monitor, "drm", NULL);
838         if (r < 0)
839                 return r;
840 
841         r = sd_device_monitor_attach_event(m->device_monitor, m->event);
842         if (r < 0)
843                 return r;
844 
845         r = sd_device_monitor_start(m->device_monitor, manager_dispatch_device_udev, m);
846         if (r < 0)
847                 return r;
848 
849         (void) sd_event_source_set_description(sd_device_monitor_get_event_source(m->device_monitor), "logind-device-monitor");
850 
851         /* Don't watch keys if nobody cares */
852         if (!manager_all_buttons_ignored(m)) {
853                 r = sd_device_monitor_new(&m->device_button_monitor);
854                 if (r < 0)
855                         return r;
856 
857                 r = sd_device_monitor_filter_add_match_tag(m->device_button_monitor, "power-switch");
858                 if (r < 0)
859                         return r;
860 
861                 r = sd_device_monitor_filter_add_match_subsystem_devtype(m->device_button_monitor, "input", NULL);
862                 if (r < 0)
863                         return r;
864 
865                 r = sd_device_monitor_attach_event(m->device_button_monitor, m->event);
866                 if (r < 0)
867                         return r;
868 
869                 r = sd_device_monitor_start(m->device_button_monitor, manager_dispatch_button_udev, m);
870                 if (r < 0)
871                         return r;
872 
873                 (void) sd_event_source_set_description(sd_device_monitor_get_event_source(m->device_button_monitor), "logind-button-monitor");
874         }
875 
876         /* Don't bother watching VCSA devices, if nobody cares */
877         if (m->n_autovts > 0 && m->console_active_fd >= 0) {
878 
879                 r = sd_device_monitor_new(&m->device_vcsa_monitor);
880                 if (r < 0)
881                         return r;
882 
883                 r = sd_device_monitor_filter_add_match_subsystem_devtype(m->device_vcsa_monitor, "vc", NULL);
884                 if (r < 0)
885                         return r;
886 
887                 r = sd_device_monitor_attach_event(m->device_vcsa_monitor, m->event);
888                 if (r < 0)
889                         return r;
890 
891                 r = sd_device_monitor_start(m->device_vcsa_monitor, manager_dispatch_vcsa_udev, m);
892                 if (r < 0)
893                         return r;
894 
895                 (void) sd_event_source_set_description(sd_device_monitor_get_event_source(m->device_vcsa_monitor), "logind-vcsa-monitor");
896         }
897 
898         return 0;
899 }
900 
manager_gc(Manager * m,bool drop_not_started)901 static void manager_gc(Manager *m, bool drop_not_started) {
902         Seat *seat;
903         Session *session;
904         User *user;
905 
906         assert(m);
907 
908         while ((seat = m->seat_gc_queue)) {
909                 LIST_REMOVE(gc_queue, m->seat_gc_queue, seat);
910                 seat->in_gc_queue = false;
911 
912                 if (seat_may_gc(seat, drop_not_started)) {
913                         seat_stop(seat, /* force = */ false);
914                         seat_free(seat);
915                 }
916         }
917 
918         while ((session = m->session_gc_queue)) {
919                 LIST_REMOVE(gc_queue, m->session_gc_queue, session);
920                 session->in_gc_queue = false;
921 
922                 /* First, if we are not closing yet, initiate stopping. */
923                 if (session_may_gc(session, drop_not_started) &&
924                     session_get_state(session) != SESSION_CLOSING)
925                         (void) session_stop(session, /* force = */ false);
926 
927                 /* Normally, this should make the session referenced again, if it doesn't then let's get rid
928                  * of it immediately. */
929                 if (session_may_gc(session, drop_not_started)) {
930                         (void) session_finalize(session);
931                         session_free(session);
932                 }
933         }
934 
935         while ((user = m->user_gc_queue)) {
936                 LIST_REMOVE(gc_queue, m->user_gc_queue, user);
937                 user->in_gc_queue = false;
938 
939                 /* First step: queue stop jobs */
940                 if (user_may_gc(user, drop_not_started))
941                         (void) user_stop(user, false);
942 
943                 /* Second step: finalize user */
944                 if (user_may_gc(user, drop_not_started)) {
945                         (void) user_finalize(user);
946                         user_free(user);
947                 }
948         }
949 }
950 
manager_dispatch_idle_action(sd_event_source * s,uint64_t t,void * userdata)951 static int manager_dispatch_idle_action(sd_event_source *s, uint64_t t, void *userdata) {
952         Manager *m = userdata;
953         struct dual_timestamp since;
954         usec_t n, elapse;
955         int r;
956 
957         assert(m);
958 
959         if (m->idle_action == HANDLE_IGNORE ||
960             m->idle_action_usec <= 0)
961                 return 0;
962 
963         n = now(CLOCK_MONOTONIC);
964 
965         r = manager_get_idle_hint(m, &since);
966         if (r <= 0)
967                 /* Not idle. Let's check if after a timeout it might be idle then. */
968                 elapse = n + m->idle_action_usec;
969         else {
970                 /* Idle! Let's see if it's time to do something, or if
971                  * we shall sleep for longer. */
972 
973                 if (n >= since.monotonic + m->idle_action_usec &&
974                     (m->idle_action_not_before_usec <= 0 || n >= m->idle_action_not_before_usec + m->idle_action_usec)) {
975                         log_info("System idle. Doing %s operation.", handle_action_to_string(m->idle_action));
976 
977                         manager_handle_action(m, 0, m->idle_action, false, false);
978                         m->idle_action_not_before_usec = n;
979                 }
980 
981                 elapse = MAX(since.monotonic, m->idle_action_not_before_usec) + m->idle_action_usec;
982         }
983 
984         if (!m->idle_action_event_source) {
985 
986                 r = sd_event_add_time(
987                                 m->event,
988                                 &m->idle_action_event_source,
989                                 CLOCK_MONOTONIC,
990                                 elapse, USEC_PER_SEC*30,
991                                 manager_dispatch_idle_action, m);
992                 if (r < 0)
993                         return log_error_errno(r, "Failed to add idle event source: %m");
994 
995                 r = sd_event_source_set_priority(m->idle_action_event_source, SD_EVENT_PRIORITY_IDLE+10);
996                 if (r < 0)
997                         return log_error_errno(r, "Failed to set idle event source priority: %m");
998         } else {
999                 r = sd_event_source_set_time(m->idle_action_event_source, elapse);
1000                 if (r < 0)
1001                         return log_error_errno(r, "Failed to set idle event timer: %m");
1002 
1003                 r = sd_event_source_set_enabled(m->idle_action_event_source, SD_EVENT_ONESHOT);
1004                 if (r < 0)
1005                         return log_error_errno(r, "Failed to enable idle event timer: %m");
1006         }
1007 
1008         return 0;
1009 }
1010 
manager_dispatch_reload_signal(sd_event_source * s,const struct signalfd_siginfo * si,void * userdata)1011 static int manager_dispatch_reload_signal(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {
1012         Manager *m = userdata;
1013         int r;
1014 
1015         manager_reset_config(m);
1016         r = manager_parse_config_file(m);
1017         if (r < 0)
1018                 log_warning_errno(r, "Failed to parse config file, using defaults: %m");
1019         else
1020                 log_info("Config file reloaded.");
1021 
1022         return 0;
1023 }
1024 
manager_startup(Manager * m)1025 static int manager_startup(Manager *m) {
1026         int r;
1027         Seat *seat;
1028         Session *session;
1029         User *user;
1030         Button *button;
1031         Inhibitor *inhibitor;
1032 
1033         assert(m);
1034 
1035         r = sd_event_add_signal(m->event, NULL, SIGHUP, manager_dispatch_reload_signal, m);
1036         if (r < 0)
1037                 return log_error_errno(r, "Failed to register SIGHUP handler: %m");
1038 
1039         /* Connect to utmp */
1040         manager_connect_utmp(m);
1041 
1042         /* Connect to console */
1043         r = manager_connect_console(m);
1044         if (r < 0)
1045                 return r;
1046 
1047         /* Connect to udev */
1048         r = manager_connect_udev(m);
1049         if (r < 0)
1050                 return log_error_errno(r, "Failed to create udev watchers: %m");
1051 
1052         /* Connect to the bus */
1053         r = manager_connect_bus(m);
1054         if (r < 0)
1055                 return r;
1056 
1057         /* Instantiate magic seat 0 */
1058         r = manager_add_seat(m, "seat0", &m->seat0);
1059         if (r < 0)
1060                 return log_error_errno(r, "Failed to add seat0: %m");
1061 
1062         r = manager_set_lid_switch_ignore(m, 0 + m->holdoff_timeout_usec);
1063         if (r < 0)
1064                 log_warning_errno(r, "Failed to set up lid switch ignore event source: %m");
1065 
1066         /* Deserialize state */
1067         r = manager_enumerate_devices(m);
1068         if (r < 0)
1069                 log_warning_errno(r, "Device enumeration failed: %m");
1070 
1071         r = manager_enumerate_seats(m);
1072         if (r < 0)
1073                 log_warning_errno(r, "Seat enumeration failed: %m");
1074 
1075         r = manager_enumerate_users(m);
1076         if (r < 0)
1077                 log_warning_errno(r, "User enumeration failed: %m");
1078 
1079         r = manager_enumerate_sessions(m);
1080         if (r < 0)
1081                 log_warning_errno(r, "Session enumeration failed: %m");
1082 
1083         r = manager_enumerate_inhibitors(m);
1084         if (r < 0)
1085                 log_warning_errno(r, "Inhibitor enumeration failed: %m");
1086 
1087         r = manager_enumerate_buttons(m);
1088         if (r < 0)
1089                 log_warning_errno(r, "Button enumeration failed: %m");
1090 
1091         manager_load_scheduled_shutdown(m);
1092 
1093         /* Remove stale objects before we start them */
1094         manager_gc(m, false);
1095 
1096         /* Reserve the special reserved VT */
1097         manager_reserve_vt(m);
1098 
1099         /* Read in utmp if it exists */
1100         manager_read_utmp(m);
1101 
1102         /* And start everything */
1103         HASHMAP_FOREACH(seat, m->seats)
1104                 (void) seat_start(seat);
1105 
1106         HASHMAP_FOREACH(user, m->users)
1107                 (void) user_start(user);
1108 
1109         HASHMAP_FOREACH(session, m->sessions)
1110                 (void) session_start(session, NULL, NULL);
1111 
1112         HASHMAP_FOREACH(inhibitor, m->inhibitors) {
1113                 (void) inhibitor_start(inhibitor);
1114 
1115                 /* Let's see if the inhibitor is dead now, then remove it */
1116                 if (inhibitor_is_orphan(inhibitor)) {
1117                         inhibitor_stop(inhibitor);
1118                         inhibitor_free(inhibitor);
1119                 }
1120         }
1121 
1122         HASHMAP_FOREACH(button, m->buttons)
1123                 button_check_switches(button);
1124 
1125         manager_dispatch_idle_action(NULL, 0, m);
1126 
1127         return 0;
1128 }
1129 
manager_run(Manager * m)1130 static int manager_run(Manager *m) {
1131         int r;
1132 
1133         assert(m);
1134 
1135         for (;;) {
1136                 r = sd_event_get_state(m->event);
1137                 if (r < 0)
1138                         return r;
1139                 if (r == SD_EVENT_FINISHED)
1140                         return 0;
1141 
1142                 manager_gc(m, true);
1143 
1144                 r = manager_dispatch_delayed(m, false);
1145                 if (r < 0)
1146                         return r;
1147                 if (r > 0)
1148                         continue;
1149 
1150                 r = sd_event_run(m->event, UINT64_MAX);
1151                 if (r < 0)
1152                         return r;
1153         }
1154 }
1155 
run(int argc,char * argv[])1156 static int run(int argc, char *argv[]) {
1157         _cleanup_(manager_unrefp) Manager *m = NULL;
1158         _unused_ _cleanup_(notify_on_cleanup) const char *notify_message = NULL;
1159         int r;
1160 
1161         log_set_facility(LOG_AUTH);
1162         log_setup();
1163 
1164         r = service_parse_argv("systemd-logind.service",
1165                                "Manager for user logins and devices and privileged operations.",
1166                                BUS_IMPLEMENTATIONS(&manager_object,
1167                                                    &log_control_object),
1168                                argc, argv);
1169         if (r <= 0)
1170                 return r;
1171 
1172         umask(0022);
1173 
1174         r = mac_selinux_init();
1175         if (r < 0)
1176                 return r;
1177 
1178         /* Always create the directories people can create inotify watches in. Note that some applications
1179          * might check for the existence of /run/systemd/seats/ to determine whether logind is available, so
1180          * please always make sure these directories are created early on and unconditionally. */
1181         (void) mkdir_label("/run/systemd/seats", 0755);
1182         (void) mkdir_label("/run/systemd/users", 0755);
1183         (void) mkdir_label("/run/systemd/sessions", 0755);
1184 
1185         assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGHUP, SIGTERM, SIGINT, SIGCHLD, -1) >= 0);
1186 
1187         r = manager_new(&m);
1188         if (r < 0)
1189                 return log_error_errno(r, "Failed to allocate manager object: %m");
1190 
1191         (void) manager_parse_config_file(m);
1192 
1193         r = manager_startup(m);
1194         if (r < 0)
1195                 return log_error_errno(r, "Failed to fully start up daemon: %m");
1196 
1197         notify_message = notify_start(NOTIFY_READY, NOTIFY_STOPPING);
1198         return manager_run(m);
1199 }
1200 
1201 DEFINE_MAIN_FUNCTION(run);
1202