1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
12 #include "sd-messages.h"
14 #include "alloc-util.h"
15 #include "audit-util.h"
16 #include "bus-error.h"
18 #include "daemon-util.h"
19 #include "devnum-util.h"
24 #include "format-util.h"
27 #include "logind-dbus.h"
28 #include "logind-seat-dbus.h"
29 #include "logind-session-dbus.h"
30 #include "logind-session.h"
31 #include "logind-user-dbus.h"
32 #include "mkdir-label.h"
33 #include "parse-util.h"
34 #include "path-util.h"
35 #include "process-util.h"
36 #include "serialize.h"
37 #include "string-table.h"
39 #include "terminal-util.h"
40 #include "tmpfile-util.h"
41 #include "uid-classification.h"
42 #include "user-util.h"
44 #define RELEASE_USEC (20*USEC_PER_SEC)
46 static void session_remove_fifo(Session
*s
);
47 static void session_restore_vt(Session
*s
);
49 int session_new(Session
**ret
, Manager
*m
, const char *id
) {
50 _cleanup_(session_freep
) Session
*s
= NULL
;
57 if (!session_id_valid(id
))
68 .audit_id
= AUDIT_SESSION_INVALID
,
69 .tty_validity
= _TTY_VALIDITY_INVALID
,
70 .leader
= PIDREF_NULL
,
73 s
->state_file
= path_join("/run/systemd/sessions", id
);
77 s
->id
= basename(s
->state_file
);
79 s
->devices
= hashmap_new(&devt_hash_ops
);
83 r
= hashmap_put(m
->sessions
, s
->id
, s
);
91 static int session_dispatch_leader_pidfd(sd_event_source
*es
, int fd
, uint32_t revents
, void *userdata
) {
92 Session
*s
= ASSERT_PTR(userdata
);
94 assert(s
->leader
.fd
== fd
);
95 session_stop(s
, /* force= */ false);
100 static int session_watch_pidfd(Session
*s
) {
105 assert(pidref_is_set(&s
->leader
));
107 if (s
->leader
.fd
< 0)
110 r
= sd_event_add_io(s
->manager
->event
, &s
->leader_pidfd_event_source
, s
->leader
.fd
, EPOLLIN
, session_dispatch_leader_pidfd
, s
);
114 r
= sd_event_source_set_priority(s
->leader_pidfd_event_source
, SD_EVENT_PRIORITY_IMPORTANT
);
118 (void) sd_event_source_set_description(s
->leader_pidfd_event_source
, "session-pidfd");
123 static void session_reset_leader(Session
*s
, bool keep_fdstore
) {
127 /* Clear fdstore if we're asked to, no matter if s->leader is set or not, so that when
128 * initially deserializing leader fd we clear the old fd too. */
129 (void) notify_remove_fd_warnf("session-%s-leader-fd", s
->id
);
130 s
->leader_fd_saved
= false;
133 if (!pidref_is_set(&s
->leader
))
136 s
->leader_pidfd_event_source
= sd_event_source_disable_unref(s
->leader_pidfd_event_source
);
138 (void) hashmap_remove_value(s
->manager
->sessions_by_leader
, &s
->leader
, s
);
140 return pidref_done(&s
->leader
);
143 Session
* session_free(Session
*s
) {
150 LIST_REMOVE(gc_queue
, s
->manager
->session_gc_queue
, s
);
152 s
->timer_event_source
= sd_event_source_unref(s
->timer_event_source
);
154 session_drop_controller(s
);
156 while ((sd
= hashmap_first(s
->devices
)))
157 session_device_free(sd
);
159 hashmap_free(s
->devices
);
162 LIST_REMOVE(sessions_by_user
, s
->user
->sessions
, s
);
164 if (s
->user
->display
== s
)
165 s
->user
->display
= NULL
;
167 user_update_last_session_timer(s
->user
);
171 if (s
->seat
->active
== s
)
172 s
->seat
->active
= NULL
;
173 if (s
->seat
->pending_switch
== s
)
174 s
->seat
->pending_switch
= NULL
;
176 seat_evict_position(s
->seat
, s
);
177 LIST_REMOVE(sessions_by_seat
, s
->seat
->sessions
, s
);
181 hashmap_remove(s
->manager
->session_units
, s
->scope
);
187 session_reset_leader(s
, /* keep_fdstore = */ true);
189 sd_bus_message_unref(s
->create_message
);
190 sd_bus_message_unref(s
->upgrade_message
);
194 free(s
->remote_host
);
195 free(s
->remote_user
);
199 hashmap_remove(s
->manager
->sessions
, s
->id
);
201 sd_event_source_unref(s
->fifo_event_source
);
202 safe_close(s
->fifo_fd
);
204 /* Note that we remove neither the state file nor the fifo path here, since we want both to survive
209 sd_event_source_unref(s
->stop_on_idle_event_source
);
214 void session_set_user(Session
*s
, User
*u
) {
219 LIST_PREPEND(sessions_by_user
, u
->sessions
, s
);
221 user_update_last_session_timer(u
);
224 int session_set_leader_consume(Session
*s
, PidRef _leader
) {
225 _cleanup_(pidref_done
) PidRef pidref
= _leader
;
229 assert(pidref_is_set(&pidref
));
231 if (pidref_equal(&s
->leader
, &pidref
))
234 session_reset_leader(s
, /* keep_fdstore = */ false);
236 s
->leader
= TAKE_PIDREF(pidref
);
238 r
= session_watch_pidfd(s
);
240 return log_error_errno(r
, "Failed to watch leader pidfd for session '%s': %m", s
->id
);
242 r
= hashmap_ensure_put(&s
->manager
->sessions_by_leader
, &pidref_hash_ops
, &s
->leader
, s
);
247 if (s
->leader
.fd
>= 0) {
248 r
= notify_push_fdf(s
->leader
.fd
, "session-%s-leader-fd", s
->id
);
250 log_warning_errno(r
, "Failed to push leader pidfd for session '%s', ignoring: %m", s
->id
);
252 s
->leader_fd_saved
= true;
255 (void) audit_session_from_pid(s
->leader
.pid
, &s
->audit_id
);
260 static void session_save_devices(Session
*s
, FILE *f
) {
263 if (!hashmap_isempty(s
->devices
)) {
264 fprintf(f
, "DEVICES=");
265 HASHMAP_FOREACH(sd
, s
->devices
)
266 fprintf(f
, DEVNUM_FORMAT_STR
" ", DEVNUM_FORMAT_VAL(sd
->dev
));
271 int session_save(Session
*s
) {
272 _cleanup_(unlink_and_freep
) char *temp_path
= NULL
;
273 _cleanup_fclose_
FILE *f
= NULL
;
284 r
= mkdir_safe_label("/run/systemd/sessions", 0755, 0, 0, MKDIR_WARN_MODE
);
288 r
= fopen_temporary(s
->state_file
, &f
, &temp_path
);
292 (void) fchmod(fileno(f
), 0644);
295 "# This is private data. Do not parse.\n"
302 "LEADER_FD_SAVED=%s\n",
303 s
->user
->user_record
->uid
,
304 s
->user
->user_record
->user_name
,
305 one_zero(session_is_active(s
)),
306 one_zero(s
->user
->display
== s
),
307 session_state_to_string(session_get_state(s
)),
309 one_zero(s
->leader_fd_saved
));
312 fprintf(f
, "TYPE=%s\n", session_type_to_string(s
->type
));
314 if (s
->original_type
>= 0)
315 fprintf(f
, "ORIGINAL_TYPE=%s\n", session_type_to_string(s
->original_type
));
318 fprintf(f
, "CLASS=%s\n", session_class_to_string(s
->class));
321 fprintf(f
, "SCOPE=%s\n", s
->scope
);
323 fprintf(f
, "SCOPE_JOB=%s\n", s
->scope_job
);
326 fprintf(f
, "FIFO=%s\n", s
->fifo_path
);
329 fprintf(f
, "SEAT=%s\n", s
->seat
->id
);
332 fprintf(f
, "TTY=%s\n", s
->tty
);
334 if (s
->tty_validity
>= 0)
335 fprintf(f
, "TTY_VALIDITY=%s\n", tty_validity_to_string(s
->tty_validity
));
338 fprintf(f
, "DISPLAY=%s\n", s
->display
);
340 if (s
->remote_host
) {
341 _cleanup_free_
char *escaped
= NULL
;
343 escaped
= cescape(s
->remote_host
);
349 fprintf(f
, "REMOTE_HOST=%s\n", escaped
);
352 if (s
->remote_user
) {
353 _cleanup_free_
char *escaped
= NULL
;
355 escaped
= cescape(s
->remote_user
);
361 fprintf(f
, "REMOTE_USER=%s\n", escaped
);
365 _cleanup_free_
char *escaped
= NULL
;
367 escaped
= cescape(s
->service
);
373 fprintf(f
, "SERVICE=%s\n", escaped
);
377 _cleanup_free_
char *escaped
= NULL
;
379 escaped
= cescape(s
->desktop
);
385 fprintf(f
, "DESKTOP=%s\n", escaped
);
388 if (s
->seat
&& seat_has_vts(s
->seat
))
389 fprintf(f
, "VTNR=%u\n", s
->vtnr
);
392 fprintf(f
, "POSITION=%u\n", s
->position
);
394 if (pidref_is_set(&s
->leader
))
395 fprintf(f
, "LEADER="PID_FMT
"\n", s
->leader
.pid
);
397 if (audit_session_is_valid(s
->audit_id
))
398 fprintf(f
, "AUDIT=%"PRIu32
"\n", s
->audit_id
);
400 if (dual_timestamp_is_set(&s
->timestamp
))
402 "REALTIME="USEC_FMT
"\n"
403 "MONOTONIC="USEC_FMT
"\n",
404 s
->timestamp
.realtime
,
405 s
->timestamp
.monotonic
);
408 fprintf(f
, "CONTROLLER=%s\n", s
->controller
);
409 session_save_devices(s
, f
);
412 r
= fflush_and_check(f
);
416 if (rename(temp_path
, s
->state_file
) < 0) {
421 temp_path
= mfree(temp_path
);
425 (void) unlink(s
->state_file
);
427 return log_error_errno(r
, "Failed to save session data %s: %m", s
->state_file
);
430 static int session_load_devices(Session
*s
, const char *devices
) {
435 for (const char *p
= devices
;;) {
436 _cleanup_free_
char *word
= NULL
;
440 k
= extract_first_word(&p
, &word
, NULL
, 0);
446 k
= parse_devnum(word
, &dev
);
452 /* The file descriptors for loaded devices will be reattached later. */
453 RET_GATHER(r
, session_device_new(s
, dev
, /* open_device = */ false, /* ret = */ NULL
));
457 log_error_errno(r
, "Failed to load some session devices for session '%s': %m", s
->id
);
461 int session_load(Session
*s
) {
462 _cleanup_free_
char *remote
= NULL
,
464 *tty_validity
= NULL
,
469 *leader_fd_saved
= NULL
,
471 *original_type
= NULL
,
485 r
= parse_env_file(NULL
, s
->state_file
,
488 "SCOPE_JOB", &s
->scope_job
,
489 "FIFO", &s
->fifo_path
,
492 "TTY_VALIDITY", &tty_validity
,
493 "DISPLAY", &s
->display
,
494 "REMOTE_HOST", &s
->remote_host
,
495 "REMOTE_USER", &s
->remote_user
,
496 "SERVICE", &s
->service
,
497 "DESKTOP", &s
->desktop
,
500 "POSITION", &position
,
501 "LEADER", &leader_pid
,
502 "LEADER_FD_SAVED", &leader_fd_saved
,
504 "ORIGINAL_TYPE", &original_type
,
507 "REALTIME", &realtime
,
508 "MONOTONIC", &monotonic
,
509 "CONTROLLER", &controller
,
512 "IS_DISPLAY", &is_display
);
514 return log_error_errno(r
, "Failed to read %s: %m", s
->state_file
);
521 return log_error_errno(SYNTHETIC_ERRNO(ENOENT
),
522 "UID not specified for session %s",
525 r
= parse_uid(uid
, &u
);
527 log_error("Failed to parse UID value %s for session %s.", uid
, s
->id
);
531 user
= hashmap_get(s
->manager
->users
, UID_TO_PTR(u
));
533 return log_error_errno(SYNTHETIC_ERRNO(ENOENT
),
534 "User of session %s not known.",
537 session_set_user(s
, user
);
541 k
= parse_boolean(remote
);
547 safe_atou(vtnr
, &s
->vtnr
);
549 if (seat
&& !s
->seat
) {
552 o
= hashmap_get(s
->manager
->seats
, seat
);
554 r
= seat_attach_session(o
, s
);
556 log_error("Cannot attach session %s to seat %s", s
->id
, seat
);
559 if (!s
->seat
|| !seat_has_vts(s
->seat
))
562 if (position
&& s
->seat
) {
565 safe_atou(position
, &npos
);
566 seat_claim_position(s
->seat
, s
, npos
);
572 v
= tty_validity_from_string(tty_validity
);
574 log_debug("Failed to parse TTY validity: %s", tty_validity
);
582 t
= session_type_from_string(type
);
590 ot
= session_type_from_string(original_type
);
592 s
->original_type
= ot
;
594 /* Pre-v246 compat: initialize original_type if not set in the state file */
595 s
->original_type
= s
->type
;
600 c
= session_class_from_string(class);
605 if (streq_ptr(state
, "closing"))
611 /* If we open an unopened pipe for reading we will not
612 get an EOF. to trigger an EOF we hence open it for
613 writing, but close it right away which then will
614 trigger the EOF. This will happen immediately if no
615 other process has the FIFO open for writing, i. e.
616 when the session died before logind (re)started. */
618 fd
= session_create_fifo(s
);
623 (void) deserialize_usec(realtime
, &s
->timestamp
.realtime
);
625 (void) deserialize_usec(monotonic
, &s
->timestamp
.monotonic
);
628 k
= parse_boolean(active
);
634 /* Note that when enumerating users are loaded before sessions, hence the display session to use is
635 * something we have to store along with the session and not the user, as in that case we couldn't
636 * apply it at the time we load the user. */
638 k
= parse_boolean(is_display
);
640 log_warning_errno(k
, "Failed to parse IS_DISPLAY session property: %m");
642 s
->user
->display
= s
;
646 if (bus_name_has_owner(s
->manager
->bus
, controller
, NULL
) > 0) {
647 session_set_controller(s
, controller
, false, false);
648 session_load_devices(s
, devices
);
650 session_restore_vt(s
);
654 assert(!pidref_is_set(&s
->leader
));
656 r
= parse_pid(leader_pid
, &s
->deserialized_pid
);
658 return log_error_errno(r
, "Failed to parse LEADER=%s: %m", leader_pid
);
660 if (leader_fd_saved
) {
661 r
= parse_boolean(leader_fd_saved
);
663 return log_error_errno(r
, "Failed to parse LEADER_FD_SAVED=%s: %m", leader_fd_saved
);
664 s
->leader_fd_saved
= r
> 0;
666 if (s
->leader_fd_saved
)
667 /* The leader fd will be acquired from fdstore later */
671 _cleanup_(pidref_done
) PidRef p
= PIDREF_NULL
;
673 r
= pidref_set_pid(&p
, s
->deserialized_pid
);
675 r
= session_set_leader_consume(s
, TAKE_PIDREF(p
));
677 log_warning_errno(r
, "Failed to set leader PID for session '%s': %m", s
->id
);
683 int session_activate(Session
*s
) {
684 unsigned num_pending
;
692 if (s
->seat
->active
== s
)
695 /* on seats with VTs, we let VTs manage session-switching */
696 if (seat_has_vts(s
->seat
)) {
700 return chvt(s
->vtnr
);
703 /* On seats without VTs, we implement session-switching in logind. We
704 * try to pause all session-devices and wait until the session
705 * controller acknowledged them. Once all devices are asleep, we simply
706 * switch the active session and be done.
707 * We save the session we want to switch to in seat->pending_switch and
708 * seat_complete_switch() will perform the final switch. */
710 s
->seat
->pending_switch
= s
;
712 /* if no devices are running, immediately perform the session switch */
713 num_pending
= session_device_try_pause_all(s
);
715 seat_complete_switch(s
->seat
);
720 static int session_start_scope(Session
*s
, sd_bus_message
*properties
, sd_bus_error
*error
) {
726 if (!SESSION_CLASS_WANTS_SCOPE(s
->class))
730 _cleanup_strv_free_
char **wants
= NULL
, **after
= NULL
;
731 _cleanup_free_
char *scope
= NULL
;
732 const char *description
;
734 s
->scope_job
= mfree(s
->scope_job
);
736 scope
= strjoin("session-", s
->id
, ".scope");
740 description
= strjoina("Session ", s
->id
, " of User ", s
->user
->user_record
->user_name
);
742 /* These two have StopWhenUnneeded= set, hence add a dep towards them */
743 wants
= strv_new(s
->user
->runtime_dir_unit
,
744 SESSION_CLASS_WANTS_SERVICE_MANAGER(s
->class) ? s
->user
->service_manager_unit
: STRV_IGNORE
);
748 /* We usually want to order session scopes after systemd-user-sessions.service since the
749 * latter unit is used as login session barrier for unprivileged users. However the barrier
750 * doesn't apply for root as sysadmin should always be able to log in (and without waiting
751 * for any timeout to expire) in case something goes wrong during the boot process. Since
752 * ordering after systemd-user-sessions.service and the user instance is optional we make use
753 * of STRV_IGNORE with strv_new() to skip these order constraints when needed. */
754 after
= strv_new("systemd-logind.service",
755 s
->user
->runtime_dir_unit
,
756 SESSION_CLASS_IS_EARLY(s
->class) ? STRV_IGNORE
: "systemd-user-sessions.service",
757 s
->user
->service_manager_unit
);
761 r
= manager_start_scope(
769 user_record_home_directory(s
->user
->user_record
),
774 return log_error_errno(r
, "Failed to start session scope %s: %s",
775 scope
, bus_error_message(error
, r
));
777 s
->scope
= TAKE_PTR(scope
);
780 (void) hashmap_put(s
->manager
->session_units
, s
->scope
, s
);
785 static int session_dispatch_stop_on_idle(sd_event_source
*source
, uint64_t t
, void *userdata
) {
786 Session
*s
= userdata
;
795 idle
= session_get_idle_hint(s
, &ts
);
797 log_info("Session \"%s\" of user \"%s\" is idle, stopping.", s
->id
, s
->user
->user_record
->user_name
);
799 return session_stop(s
, /* force */ true);
802 r
= sd_event_source_set_time(
804 usec_add(dual_timestamp_is_set(&ts
) ? ts
.monotonic
: now(CLOCK_MONOTONIC
),
805 s
->manager
->stop_idle_session_usec
));
807 return log_error_errno(r
, "Failed to configure stop on idle session event source: %m");
809 r
= sd_event_source_set_enabled(source
, SD_EVENT_ONESHOT
);
811 return log_error_errno(r
, "Failed to enable stop on idle session event source: %m");
816 static int session_setup_stop_on_idle_timer(Session
*s
) {
821 if (s
->manager
->stop_idle_session_usec
== USEC_INFINITY
|| !SESSION_CLASS_CAN_STOP_ON_IDLE(s
->class))
824 r
= sd_event_add_time_relative(
826 &s
->stop_on_idle_event_source
,
828 s
->manager
->stop_idle_session_usec
,
830 session_dispatch_stop_on_idle
, s
);
832 return log_error_errno(r
, "Failed to add stop on idle session event source: %m");
837 int session_start(Session
*s
, sd_bus_message
*properties
, sd_bus_error
*error
) {
851 r
= user_start(s
->user
);
855 r
= session_start_scope(s
, properties
, error
);
859 r
= session_setup_stop_on_idle_timer(s
);
863 log_struct(s
->class == SESSION_BACKGROUND
? LOG_DEBUG
: LOG_INFO
,
864 "MESSAGE_ID=" SD_MESSAGE_SESSION_START_STR
,
865 "SESSION_ID=%s", s
->id
,
866 "USER_ID=%s", s
->user
->user_record
->user_name
,
867 "LEADER="PID_FMT
, s
->leader
.pid
,
868 LOG_MESSAGE("New session %s of user %s.", s
->id
, s
->user
->user_record
->user_name
));
870 if (!dual_timestamp_is_set(&s
->timestamp
))
871 dual_timestamp_now(&s
->timestamp
);
874 seat_read_active_vt(s
->seat
);
878 user_elect_display(s
->user
);
881 (void) session_save(s
);
882 (void) user_save(s
->user
);
884 (void) seat_save(s
->seat
);
887 session_send_signal(s
, true);
888 user_send_changed(s
->user
, "Display", NULL
);
890 if (s
->seat
&& s
->seat
->active
== s
)
891 (void) seat_send_changed(s
->seat
, "ActiveSession", NULL
);
896 static int session_stop_scope(Session
*s
, bool force
) {
897 _cleanup_(sd_bus_error_free
) sd_bus_error error
= SD_BUS_ERROR_NULL
;
905 /* Let's always abandon the scope first. This tells systemd that we are not interested anymore, and everything
906 * that is left in the scope is "left-over". Informing systemd about this has the benefit that it will log
907 * when killing any processes left after this point. */
908 r
= manager_abandon_scope(s
->manager
, s
->scope
, &error
);
910 log_warning_errno(r
, "Failed to abandon session scope, ignoring: %s", bus_error_message(&error
, r
));
911 sd_bus_error_free(&error
);
914 s
->scope_job
= mfree(s
->scope_job
);
916 /* Optionally, let's kill everything that's left now. */
918 (s
->user
->user_record
->kill_processes
!= 0 &&
919 (s
->user
->user_record
->kill_processes
> 0 ||
920 manager_shall_kill(s
->manager
, s
->user
->user_record
->user_name
)))) {
922 r
= manager_stop_unit(s
->manager
, s
->scope
, force
? "replace" : "fail", &error
, &s
->scope_job
);
925 return log_error_errno(r
, "Failed to stop session scope: %s", bus_error_message(&error
, r
));
927 log_warning_errno(r
, "Failed to stop session scope, ignoring: %s", bus_error_message(&error
, r
));
931 /* With no killing, this session is allowed to persist in "closing" state indefinitely.
932 * Therefore session stop and session removal may be two distinct events.
933 * Session stop is quite significant on its own, let's log it. */
934 log_struct(s
->class == SESSION_BACKGROUND
? LOG_DEBUG
: LOG_INFO
,
935 "SESSION_ID=%s", s
->id
,
936 "USER_ID=%s", s
->user
->user_record
->user_name
,
937 "LEADER="PID_FMT
, s
->leader
.pid
,
938 LOG_MESSAGE("Session %s logged out. Waiting for processes to exit.", s
->id
));
944 int session_stop(Session
*s
, bool force
) {
949 /* This is called whenever we begin with tearing down a session record. It's called in four cases: explicit API
950 * request via the bus (either directly for the session object or for the seat or user object this session
951 * belongs to; 'force' is true), or due to automatic GC (i.e. scope vanished; 'force' is false), or because the
952 * session FIFO saw an EOF ('force' is false), or because the release timer hit ('force' is false). */
961 s
->timer_event_source
= sd_event_source_unref(s
->timer_event_source
);
962 s
->leader_pidfd_event_source
= sd_event_source_unref(s
->leader_pidfd_event_source
);
965 seat_evict_position(s
->seat
, s
);
967 /* We are going down, don't care about FIFOs anymore */
968 session_remove_fifo(s
);
971 r
= session_stop_scope(s
, force
);
975 user_elect_display(s
->user
);
977 (void) session_save(s
);
978 (void) user_save(s
->user
);
983 int session_finalize(Session
*s
) {
992 log_struct(s
->class == SESSION_BACKGROUND
? LOG_DEBUG
: LOG_INFO
,
993 "MESSAGE_ID=" SD_MESSAGE_SESSION_STOP_STR
,
994 "SESSION_ID=%s", s
->id
,
995 "USER_ID=%s", s
->user
->user_record
->user_name
,
996 "LEADER="PID_FMT
, s
->leader
.pid
,
997 LOG_MESSAGE("Removed session %s.", s
->id
));
999 s
->timer_event_source
= sd_event_source_unref(s
->timer_event_source
);
1002 seat_evict_position(s
->seat
, s
);
1004 /* Kill session devices */
1005 while ((sd
= hashmap_first(s
->devices
)))
1006 session_device_free(sd
);
1008 (void) unlink(s
->state_file
);
1009 session_add_to_gc_queue(s
);
1010 user_add_to_gc_queue(s
->user
);
1013 session_send_signal(s
, false);
1018 if (s
->seat
->active
== s
)
1019 seat_set_active(s
->seat
, NULL
);
1024 session_reset_leader(s
, /* keep_fdstore = */ false);
1026 (void) user_save(s
->user
);
1027 (void) user_send_changed(s
->user
, "Display", NULL
);
1032 static int release_timeout_callback(sd_event_source
*es
, uint64_t usec
, void *userdata
) {
1033 Session
*s
= ASSERT_PTR(userdata
);
1037 session_stop(s
, /* force = */ false);
1041 int session_release(Session
*s
) {
1044 if (!s
->started
|| s
->stopping
)
1047 if (s
->timer_event_source
)
1050 return sd_event_add_time_relative(
1052 &s
->timer_event_source
,
1055 release_timeout_callback
, s
);
1058 bool session_is_active(Session
*s
) {
1064 return s
->seat
->active
== s
;
1067 static int get_tty_atime(const char *tty
, usec_t
*atime
) {
1068 _cleanup_free_
char *p
= NULL
;
1074 if (!path_is_absolute(tty
)) {
1075 p
= path_join("/dev", tty
);
1080 } else if (!path_startswith(tty
, "/dev/"))
1083 if (lstat(tty
, &st
) < 0)
1086 *atime
= timespec_load(&st
.st_atim
);
1090 static int get_process_ctty_atime(pid_t pid
, usec_t
*atime
) {
1091 _cleanup_free_
char *p
= NULL
;
1097 r
= get_ctty(pid
, NULL
, &p
);
1101 return get_tty_atime(p
, atime
);
1104 int session_get_idle_hint(Session
*s
, dual_timestamp
*t
) {
1105 usec_t atime
= 0, dtime
= 0;
1110 /* Graphical sessions have an explicit idle hint */
1111 if (SESSION_TYPE_IS_GRAPHICAL(s
->type
)) {
1113 *t
= s
->idle_hint_timestamp
;
1115 return s
->idle_hint
;
1118 if (s
->type
== SESSION_TTY
) {
1119 /* For sessions with an explicitly configured tty, let's check its atime */
1121 r
= get_tty_atime(s
->tty
, &atime
);
1126 /* For sessions with a leader but no explicitly configured tty, let's check the controlling tty of
1128 if (pidref_is_set(&s
->leader
)) {
1129 r
= get_process_ctty_atime(s
->leader
.pid
, &atime
);
1136 *t
= DUAL_TIMESTAMP_NULL
;
1142 dual_timestamp_from_realtime(t
, atime
);
1144 if (s
->manager
->idle_action_usec
> 0 && s
->manager
->stop_idle_session_usec
!= USEC_INFINITY
)
1145 dtime
= MIN(s
->manager
->idle_action_usec
, s
->manager
->stop_idle_session_usec
);
1146 else if (s
->manager
->idle_action_usec
> 0)
1147 dtime
= s
->manager
->idle_action_usec
;
1148 else if (s
->manager
->stop_idle_session_usec
!= USEC_INFINITY
)
1149 dtime
= s
->manager
->stop_idle_session_usec
;
1153 return usec_add(atime
, dtime
) <= now(CLOCK_REALTIME
);
1156 int session_set_idle_hint(Session
*s
, bool b
) {
1159 if (!SESSION_CLASS_CAN_IDLE(s
->class)) /* Only some session classes know the idle concept at all */
1161 if (!SESSION_TYPE_IS_GRAPHICAL(s
->type
)) /* And only graphical session types can set the field explicitly */
1164 if (s
->idle_hint
== b
)
1168 dual_timestamp_now(&s
->idle_hint_timestamp
);
1170 session_send_changed(s
, "IdleHint", "IdleSinceHint", "IdleSinceHintMonotonic", NULL
);
1173 seat_send_changed(s
->seat
, "IdleHint", "IdleSinceHint", "IdleSinceHintMonotonic", NULL
);
1175 user_send_changed(s
->user
, "IdleHint", "IdleSinceHint", "IdleSinceHintMonotonic", NULL
);
1176 manager_send_changed(s
->manager
, "IdleHint", "IdleSinceHint", "IdleSinceHintMonotonic", NULL
);
1181 int session_get_locked_hint(Session
*s
) {
1184 return s
->locked_hint
;
1187 int session_set_locked_hint(Session
*s
, bool b
) {
1190 if (!SESSION_CLASS_CAN_LOCK(s
->class))
1193 if (s
->locked_hint
== b
)
1197 (void) session_save(s
);
1198 (void) session_send_changed(s
, "LockedHint", NULL
);
1203 void session_set_type(Session
*s
, SessionType t
) {
1210 (void) session_save(s
);
1211 (void) session_send_changed(s
, "Type", NULL
);
1214 void session_set_class(Session
*s
, SessionClass c
) {
1221 (void) session_save(s
);
1222 (void) session_send_changed(s
, "Class", NULL
);
1224 /* This class change might mean we need the per-user session manager now. Try to start it. */
1225 (void) user_start_service_manager(s
->user
);
1228 int session_set_display(Session
*s
, const char *display
) {
1234 r
= free_and_strdup(&s
->display
, display
);
1235 if (r
<= 0) /* 0 means the strings were equal */
1238 (void) session_save(s
);
1239 (void) session_send_changed(s
, "Display", NULL
);
1244 int session_set_tty(Session
*s
, const char *tty
) {
1250 r
= free_and_strdup(&s
->tty
, tty
);
1251 if (r
<= 0) /* 0 means the strings were equal */
1254 (void) session_save(s
);
1255 (void) session_send_changed(s
, "TTY", NULL
);
1260 static int session_dispatch_fifo(sd_event_source
*es
, int fd
, uint32_t revents
, void *userdata
) {
1261 Session
*s
= ASSERT_PTR(userdata
);
1263 assert(s
->fifo_fd
== fd
);
1265 /* EOF on the FIFO means the session died abnormally. */
1267 session_remove_fifo(s
);
1268 session_stop(s
, /* force = */ false);
1273 int session_create_fifo(Session
*s
) {
1279 if (!s
->fifo_path
) {
1280 r
= mkdir_safe_label("/run/systemd/sessions", 0755, 0, 0, MKDIR_WARN_MODE
);
1284 s
->fifo_path
= strjoin("/run/systemd/sessions/", s
->id
, ".ref");
1288 if (mkfifo(s
->fifo_path
, 0600) < 0 && errno
!= EEXIST
)
1292 /* Open reading side */
1293 if (s
->fifo_fd
< 0) {
1294 s
->fifo_fd
= open(s
->fifo_path
, O_RDONLY
|O_CLOEXEC
|O_NONBLOCK
);
1299 if (!s
->fifo_event_source
) {
1300 r
= sd_event_add_io(s
->manager
->event
, &s
->fifo_event_source
, s
->fifo_fd
, 0, session_dispatch_fifo
, s
);
1304 /* Let's make sure we noticed dead sessions before we process new bus requests (which might
1305 * create new sessions). */
1306 r
= sd_event_source_set_priority(s
->fifo_event_source
, SD_EVENT_PRIORITY_NORMAL
-10);
1311 /* Open writing side */
1312 return RET_NERRNO(open(s
->fifo_path
, O_WRONLY
|O_CLOEXEC
|O_NONBLOCK
));
1315 static void session_remove_fifo(Session
*s
) {
1318 s
->fifo_event_source
= sd_event_source_unref(s
->fifo_event_source
);
1319 s
->fifo_fd
= safe_close(s
->fifo_fd
);
1320 s
->fifo_path
= unlink_and_free(s
->fifo_path
);
1323 bool session_may_gc(Session
*s
, bool drop_not_started
) {
1328 if (drop_not_started
&& !s
->started
)
1334 r
= pidref_is_alive(&s
->leader
);
1336 /* Session has no leader. This is probably because the leader vanished before deserializing
1337 * pidfd from FD store. */
1340 log_debug_errno(r
, "Unable to determine if leader PID " PID_FMT
" is still alive, assuming not: %m", s
->leader
.pid
);
1344 if (s
->fifo_fd
>= 0 && pipe_eof(s
->fifo_fd
) <= 0)
1348 _cleanup_(sd_bus_error_free
) sd_bus_error error
= SD_BUS_ERROR_NULL
;
1350 r
= manager_job_is_active(s
->manager
, s
->scope_job
, &error
);
1352 log_debug_errno(r
, "Failed to determine whether job '%s' is pending, ignoring: %s", s
->scope_job
, bus_error_message(&error
, r
));
1358 _cleanup_(sd_bus_error_free
) sd_bus_error error
= SD_BUS_ERROR_NULL
;
1360 r
= manager_unit_is_active(s
->manager
, s
->scope
, &error
);
1362 log_debug_errno(r
, "Failed to determine whether unit '%s' is active, ignoring: %s", s
->scope
, bus_error_message(&error
, r
));
1370 void session_add_to_gc_queue(Session
*s
) {
1376 LIST_PREPEND(gc_queue
, s
->manager
->session_gc_queue
, s
);
1377 s
->in_gc_queue
= true;
1380 SessionState
session_get_state(Session
*s
) {
1383 /* always check closing first */
1384 if (s
->stopping
|| s
->timer_event_source
)
1385 return SESSION_CLOSING
;
1387 if (s
->scope_job
|| (!pidref_is_set(&s
->leader
) && s
->fifo_fd
< 0))
1388 return SESSION_OPENING
;
1390 if (session_is_active(s
))
1391 return SESSION_ACTIVE
;
1393 return SESSION_ONLINE
;
1396 int session_kill(Session
*s
, KillWho who
, int signo
) {
1402 return manager_kill_unit(s
->manager
, s
->scope
, who
, signo
, NULL
);
1405 static int session_open_vt(Session
*s
, bool reopen
) {
1406 _cleanup_close_
int fd
= -EBADF
;
1407 char path
[sizeof("/dev/tty") + DECIMAL_STR_MAX(s
->vtnr
)];
1414 if (!reopen
&& s
->vtfd
>= 0)
1417 sprintf(path
, "/dev/tty%u", s
->vtnr
);
1419 fd
= open_terminal(path
, O_RDWR
| O_CLOEXEC
| O_NONBLOCK
| O_NOCTTY
);
1421 return log_error_errno(fd
, "Cannot open VT %s of session %s: %m", path
, s
->id
);
1423 close_and_replace(s
->vtfd
, fd
);
1427 static int session_prepare_vt(Session
*s
) {
1429 struct vt_mode mode
= {};
1436 vt
= session_open_vt(s
, /* reopen = */ false);
1440 r
= fchown(vt
, s
->user
->user_record
->uid
, -1);
1442 r
= log_error_errno(errno
,
1443 "Cannot change owner of /dev/tty%u: %m",
1448 r
= ioctl(vt
, KDSKBMODE
, K_OFF
);
1450 r
= log_error_errno(errno
,
1451 "Cannot set K_OFF on /dev/tty%u: %m",
1456 r
= ioctl(vt
, KDSETMODE
, KD_GRAPHICS
);
1458 r
= log_error_errno(errno
,
1459 "Cannot set KD_GRAPHICS on /dev/tty%u: %m",
1464 /* Oh, thanks to the VT layer, VT_AUTO does not work with KD_GRAPHICS.
1465 * So we need a dummy handler here which just acknowledges *all* VT
1466 * switch requests. */
1467 mode
.mode
= VT_PROCESS
;
1468 mode
.relsig
= SIGRTMIN
;
1469 mode
.acqsig
= SIGRTMIN
+ 1;
1470 r
= ioctl(vt
, VT_SETMODE
, &mode
);
1472 r
= log_error_errno(errno
,
1473 "Cannot set VT_PROCESS on /dev/tty%u: %m",
1481 session_restore_vt(s
);
1485 static void session_restore_vt(Session
*s
) {
1493 r
= vt_restore(s
->vtfd
);
1495 /* It might happen if the controlling process exited before or while we were
1496 * restoring the VT as it would leave the old file-descriptor in a hung-up
1497 * state. In this case let's retry with a fresh handle to the virtual terminal. */
1499 /* We do a little dance to avoid having the terminal be available
1500 * for reuse before we've cleaned it up. */
1502 int fd
= session_open_vt(s
, /* reopen = */ true);
1507 log_warning_errno(r
, "Failed to restore VT, ignoring: %m");
1509 s
->vtfd
= safe_close(s
->vtfd
);
1512 void session_leave_vt(Session
*s
) {
1517 /* This is called whenever we get a VT-switch signal from the kernel.
1518 * We acknowledge all of them unconditionally. Note that session are
1519 * free to overwrite those handlers and we only register them for
1520 * sessions with controllers. Legacy sessions are not affected.
1521 * However, if we switch from a non-legacy to a legacy session, we must
1522 * make sure to pause all device before acknowledging the switch. We
1523 * process the real switch only after we are notified via sysfs, so the
1524 * legacy session might have already started using the devices. If we
1525 * don't pause the devices before the switch, we might confuse the
1526 * session we switch to. */
1531 session_device_pause_all(s
);
1532 r
= vt_release(s
->vtfd
, /* restore = */ false);
1534 /* Handle the same VT hung-up case as in session_restore_vt */
1536 int fd
= session_open_vt(s
, /* reopen = */ true);
1538 r
= vt_release(fd
, /* restore = */ false);
1541 log_debug_errno(r
, "Cannot release VT of session %s: %m", s
->id
);
1544 bool session_is_controller(Session
*s
, const char *sender
) {
1545 return streq_ptr(ASSERT_PTR(s
)->controller
, sender
);
1548 static void session_release_controller(Session
*s
, bool notify
) {
1549 _unused_ _cleanup_free_
char *name
= NULL
;
1557 name
= s
->controller
;
1559 /* By resetting the controller before releasing the devices, we won't send notification signals.
1560 * This avoids sending useless notifications if the controller is released on disconnects. */
1562 s
->controller
= NULL
;
1564 while ((sd
= hashmap_first(s
->devices
)))
1565 session_device_free(sd
);
1567 s
->controller
= NULL
;
1568 s
->track
= sd_bus_track_unref(s
->track
);
1571 static int on_bus_track(sd_bus_track
*track
, void *userdata
) {
1572 Session
*s
= ASSERT_PTR(userdata
);
1576 session_drop_controller(s
);
1581 int session_set_controller(Session
*s
, const char *sender
, bool force
, bool prepare
) {
1582 _cleanup_free_
char *name
= NULL
;
1588 if (session_is_controller(s
, sender
))
1590 if (s
->controller
&& !force
)
1593 name
= strdup(sender
);
1597 s
->track
= sd_bus_track_unref(s
->track
);
1598 r
= sd_bus_track_new(s
->manager
->bus
, &s
->track
, on_bus_track
, s
);
1602 r
= sd_bus_track_add_name(s
->track
, name
);
1606 /* When setting a session controller, we forcibly mute the VT and set
1607 * it into graphics-mode. Applications can override that by changing
1608 * VT state after calling TakeControl(). However, this serves as a good
1609 * default and well-behaving controllers can now ignore VTs entirely.
1610 * Note that we reset the VT on ReleaseControl() and if the controller
1612 * If logind crashes/restarts, we restore the controller during restart
1613 * (without preparing the VT since the controller has probably overridden
1614 * VT state by now) or reset the VT in case it crashed/exited, too. */
1616 r
= session_prepare_vt(s
);
1618 s
->track
= sd_bus_track_unref(s
->track
);
1623 session_release_controller(s
, true);
1624 s
->controller
= TAKE_PTR(name
);
1625 (void) session_save(s
);
1630 void session_drop_controller(Session
*s
) {
1636 s
->track
= sd_bus_track_unref(s
->track
);
1637 session_set_type(s
, s
->original_type
);
1638 session_release_controller(s
, false);
1639 (void) session_save(s
);
1640 session_restore_vt(s
);
1643 static const char* const session_state_table
[_SESSION_STATE_MAX
] = {
1644 [SESSION_OPENING
] = "opening",
1645 [SESSION_ONLINE
] = "online",
1646 [SESSION_ACTIVE
] = "active",
1647 [SESSION_CLOSING
] = "closing",
1650 DEFINE_STRING_TABLE_LOOKUP(session_state
, SessionState
);
1652 static const char* const session_type_table
[_SESSION_TYPE_MAX
] = {
1653 [SESSION_UNSPECIFIED
] = "unspecified",
1654 [SESSION_TTY
] = "tty",
1655 [SESSION_X11
] = "x11",
1656 [SESSION_WAYLAND
] = "wayland",
1657 [SESSION_MIR
] = "mir",
1658 [SESSION_WEB
] = "web",
1661 DEFINE_STRING_TABLE_LOOKUP(session_type
, SessionType
);
1663 static const char* const session_class_table
[_SESSION_CLASS_MAX
] = {
1664 [SESSION_USER
] = "user",
1665 [SESSION_USER_EARLY
] = "user-early",
1666 [SESSION_USER_INCOMPLETE
] = "user-incomplete",
1667 [SESSION_GREETER
] = "greeter",
1668 [SESSION_LOCK_SCREEN
] = "lock-screen",
1669 [SESSION_BACKGROUND
] = "background",
1670 [SESSION_BACKGROUND_LIGHT
] = "background-light",
1671 [SESSION_MANAGER
] = "manager",
1672 [SESSION_MANAGER_EARLY
] = "manager-early",
1675 DEFINE_STRING_TABLE_LOOKUP(session_class
, SessionClass
);
1677 static const char* const kill_who_table
[_KILL_WHO_MAX
] = {
1678 [KILL_LEADER
] = "leader",
1682 DEFINE_STRING_TABLE_LOOKUP(kill_who
, KillWho
);
1684 static const char* const tty_validity_table
[_TTY_VALIDITY_MAX
] = {
1685 [TTY_FROM_PAM
] = "from-pam",
1686 [TTY_FROM_UTMP
] = "from-utmp",
1687 [TTY_UTMP_INCONSISTENT
] = "utmp-inconsistent",
1690 DEFINE_STRING_TABLE_LOOKUP(tty_validity
, TTYValidity
);