1 /* SPDX-License-Identifier: LGPL-2.1+ */
12 #include "sd-messages.h"
14 #include "alloc-util.h"
15 #include "audit-util.h"
16 #include "bus-error.h"
22 #include "format-util.h"
24 #include "logind-dbus.h"
25 #include "logind-seat-dbus.h"
26 #include "logind-session-dbus.h"
27 #include "logind-session.h"
28 #include "logind-user-dbus.h"
30 #include "parse-util.h"
31 #include "path-util.h"
32 #include "process-util.h"
33 #include "serialize.h"
34 #include "string-table.h"
36 #include "terminal-util.h"
37 #include "tmpfile-util.h"
38 #include "user-util.h"
41 #define RELEASE_USEC (20*USEC_PER_SEC)
43 static void session_remove_fifo(Session
*s
);
44 static void session_restore_vt(Session
*s
);
46 int session_new(Session
**ret
, Manager
*m
, const char *id
) {
47 _cleanup_(session_freep
) Session
*s
= NULL
;
54 if (!session_id_valid(id
))
65 .audit_id
= AUDIT_SESSION_INVALID
,
66 .tty_validity
= _TTY_VALIDITY_INVALID
,
69 s
->state_file
= path_join("/run/systemd/sessions", id
);
73 s
->id
= basename(s
->state_file
);
75 s
->devices
= hashmap_new(&devt_hash_ops
);
79 r
= hashmap_put(m
->sessions
, s
->id
, s
);
87 Session
* session_free(Session
*s
) {
94 LIST_REMOVE(gc_queue
, s
->manager
->session_gc_queue
, s
);
96 s
->timer_event_source
= sd_event_source_unref(s
->timer_event_source
);
98 session_drop_controller(s
);
100 while ((sd
= hashmap_first(s
->devices
)))
101 session_device_free(sd
);
103 hashmap_free(s
->devices
);
106 LIST_REMOVE(sessions_by_user
, s
->user
->sessions
, s
);
108 if (s
->user
->display
== s
)
109 s
->user
->display
= NULL
;
111 user_update_last_session_timer(s
->user
);
115 if (s
->seat
->active
== s
)
116 s
->seat
->active
= NULL
;
117 if (s
->seat
->pending_switch
== s
)
118 s
->seat
->pending_switch
= NULL
;
120 seat_evict_position(s
->seat
, s
);
121 LIST_REMOVE(sessions_by_seat
, s
->seat
->sessions
, s
);
125 hashmap_remove(s
->manager
->session_units
, s
->scope
);
129 if (pid_is_valid(s
->leader
))
130 (void) hashmap_remove_value(s
->manager
->sessions_by_leader
, PID_TO_PTR(s
->leader
), s
);
134 sd_bus_message_unref(s
->create_message
);
138 free(s
->remote_host
);
139 free(s
->remote_user
);
143 hashmap_remove(s
->manager
->sessions
, s
->id
);
145 sd_event_source_unref(s
->fifo_event_source
);
146 safe_close(s
->fifo_fd
);
148 /* Note that we remove neither the state file nor the fifo path here, since we want both to survive
156 void session_set_user(Session
*s
, User
*u
) {
161 LIST_PREPEND(sessions_by_user
, u
->sessions
, s
);
163 user_update_last_session_timer(u
);
166 int session_set_leader(Session
*s
, pid_t pid
) {
171 if (!pid_is_valid(pid
))
174 if (s
->leader
== pid
)
177 r
= hashmap_put(s
->manager
->sessions_by_leader
, PID_TO_PTR(pid
), s
);
181 if (pid_is_valid(s
->leader
))
182 (void) hashmap_remove_value(s
->manager
->sessions_by_leader
, PID_TO_PTR(s
->leader
), s
);
185 (void) audit_session_from_pid(pid
, &s
->audit_id
);
190 static void session_save_devices(Session
*s
, FILE *f
) {
194 if (!hashmap_isempty(s
->devices
)) {
195 fprintf(f
, "DEVICES=");
196 HASHMAP_FOREACH(sd
, s
->devices
, i
)
197 fprintf(f
, "%u:%u ", major(sd
->dev
), minor(sd
->dev
));
202 int session_save(Session
*s
) {
203 _cleanup_free_
char *temp_path
= NULL
;
204 _cleanup_fclose_
FILE *f
= NULL
;
215 r
= mkdir_safe_label("/run/systemd/sessions", 0755, 0, 0, MKDIR_WARN_MODE
);
219 r
= fopen_temporary(s
->state_file
, &f
, &temp_path
);
223 (void) fchmod(fileno(f
), 0644);
226 "# This is private data. Do not parse.\n"
233 s
->user
->user_record
->uid
,
234 s
->user
->user_record
->user_name
,
235 session_is_active(s
),
236 s
->user
->display
== s
,
237 session_state_to_string(session_get_state(s
)),
241 fprintf(f
, "TYPE=%s\n", session_type_to_string(s
->type
));
243 if (s
->original_type
>= 0)
244 fprintf(f
, "ORIGINAL_TYPE=%s\n", session_type_to_string(s
->original_type
));
247 fprintf(f
, "CLASS=%s\n", session_class_to_string(s
->class));
250 fprintf(f
, "SCOPE=%s\n", s
->scope
);
252 fprintf(f
, "SCOPE_JOB=%s\n", s
->scope_job
);
255 fprintf(f
, "FIFO=%s\n", s
->fifo_path
);
258 fprintf(f
, "SEAT=%s\n", s
->seat
->id
);
261 fprintf(f
, "TTY=%s\n", s
->tty
);
263 if (s
->tty_validity
>= 0)
264 fprintf(f
, "TTY_VALIDITY=%s\n", tty_validity_to_string(s
->tty_validity
));
267 fprintf(f
, "DISPLAY=%s\n", s
->display
);
269 if (s
->remote_host
) {
270 _cleanup_free_
char *escaped
;
272 escaped
= cescape(s
->remote_host
);
278 fprintf(f
, "REMOTE_HOST=%s\n", escaped
);
281 if (s
->remote_user
) {
282 _cleanup_free_
char *escaped
;
284 escaped
= cescape(s
->remote_user
);
290 fprintf(f
, "REMOTE_USER=%s\n", escaped
);
294 _cleanup_free_
char *escaped
;
296 escaped
= cescape(s
->service
);
302 fprintf(f
, "SERVICE=%s\n", escaped
);
306 _cleanup_free_
char *escaped
;
308 escaped
= cescape(s
->desktop
);
314 fprintf(f
, "DESKTOP=%s\n", escaped
);
317 if (s
->seat
&& seat_has_vts(s
->seat
))
318 fprintf(f
, "VTNR=%u\n", s
->vtnr
);
321 fprintf(f
, "POSITION=%u\n", s
->position
);
323 if (pid_is_valid(s
->leader
))
324 fprintf(f
, "LEADER="PID_FMT
"\n", s
->leader
);
326 if (audit_session_is_valid(s
->audit_id
))
327 fprintf(f
, "AUDIT=%"PRIu32
"\n", s
->audit_id
);
329 if (dual_timestamp_is_set(&s
->timestamp
))
331 "REALTIME="USEC_FMT
"\n"
332 "MONOTONIC="USEC_FMT
"\n",
333 s
->timestamp
.realtime
,
334 s
->timestamp
.monotonic
);
337 fprintf(f
, "CONTROLLER=%s\n", s
->controller
);
338 session_save_devices(s
, f
);
341 r
= fflush_and_check(f
);
345 if (rename(temp_path
, s
->state_file
) < 0) {
353 (void) unlink(s
->state_file
);
356 (void) unlink(temp_path
);
358 return log_error_errno(r
, "Failed to save session data %s: %m", s
->state_file
);
361 static int session_load_devices(Session
*s
, const char *devices
) {
367 for (p
= devices
;;) {
368 _cleanup_free_
char *word
= NULL
;
373 k
= extract_first_word(&p
, &word
, NULL
, 0);
381 k
= parse_dev(word
, &dev
);
387 /* The file descriptors for loaded devices will be reattached later. */
388 k
= session_device_new(s
, dev
, false, &sd
);
394 log_error_errno(r
, "Loading session devices for session %s failed: %m", s
->id
);
399 int session_load(Session
*s
) {
400 _cleanup_free_
char *remote
= NULL
,
402 *tty_validity
= NULL
,
408 *original_type
= NULL
,
422 r
= parse_env_file(NULL
, s
->state_file
,
425 "SCOPE_JOB", &s
->scope_job
,
426 "FIFO", &s
->fifo_path
,
429 "TTY_VALIDITY", &tty_validity
,
430 "DISPLAY", &s
->display
,
431 "REMOTE_HOST", &s
->remote_host
,
432 "REMOTE_USER", &s
->remote_user
,
433 "SERVICE", &s
->service
,
434 "DESKTOP", &s
->desktop
,
437 "POSITION", &position
,
440 "ORIGINAL_TYPE", &original_type
,
443 "REALTIME", &realtime
,
444 "MONOTONIC", &monotonic
,
445 "CONTROLLER", &controller
,
448 "IS_DISPLAY", &is_display
);
451 return log_error_errno(r
, "Failed to read %s: %m", s
->state_file
);
458 return log_error_errno(SYNTHETIC_ERRNO(ENOENT
),
459 "UID not specified for session %s",
462 r
= parse_uid(uid
, &u
);
464 log_error("Failed to parse UID value %s for session %s.", uid
, s
->id
);
468 user
= hashmap_get(s
->manager
->users
, UID_TO_PTR(u
));
470 return log_error_errno(SYNTHETIC_ERRNO(ENOENT
),
471 "User of session %s not known.",
474 session_set_user(s
, user
);
478 k
= parse_boolean(remote
);
484 safe_atou(vtnr
, &s
->vtnr
);
486 if (seat
&& !s
->seat
) {
489 o
= hashmap_get(s
->manager
->seats
, seat
);
491 r
= seat_attach_session(o
, s
);
493 log_error("Cannot attach session %s to seat %s", s
->id
, seat
);
496 if (!s
->seat
|| !seat_has_vts(s
->seat
))
499 if (position
&& s
->seat
) {
502 safe_atou(position
, &npos
);
503 seat_claim_position(s
->seat
, s
, npos
);
509 v
= tty_validity_from_string(tty_validity
);
511 log_debug("Failed to parse TTY validity: %s", tty_validity
);
519 r
= parse_pid(leader
, &pid
);
521 log_debug_errno(r
, "Failed to parse leader PID of session: %s", leader
);
523 r
= session_set_leader(s
, pid
);
525 log_warning_errno(r
, "Failed to set session leader PID, ignoring: %m");
532 t
= session_type_from_string(type
);
540 ot
= session_type_from_string(original_type
);
542 s
->original_type
= ot
;
544 /* Pre-v246 compat: initialize original_type if not set in the state file */
545 s
->original_type
= s
->type
;
550 c
= session_class_from_string(class);
555 if (state
&& streq(state
, "closing"))
561 /* If we open an unopened pipe for reading we will not
562 get an EOF. to trigger an EOF we hence open it for
563 writing, but close it right away which then will
564 trigger the EOF. This will happen immediately if no
565 other process has the FIFO open for writing, i. e.
566 when the session died before logind (re)started. */
568 fd
= session_create_fifo(s
);
573 (void) deserialize_usec(realtime
, &s
->timestamp
.realtime
);
575 (void) deserialize_usec(monotonic
, &s
->timestamp
.monotonic
);
578 k
= parse_boolean(active
);
584 /* Note that when enumerating users are loaded before sessions, hence the display session to use is
585 * something we have to store along with the session and not the user, as in that case we couldn't
586 * apply it at the time we load the user. */
588 k
= parse_boolean(is_display
);
590 log_warning_errno(k
, "Failed to parse IS_DISPLAY session property: %m");
592 s
->user
->display
= s
;
596 if (bus_name_has_owner(s
->manager
->bus
, controller
, NULL
) > 0) {
597 session_set_controller(s
, controller
, false, false);
598 session_load_devices(s
, devices
);
600 session_restore_vt(s
);
606 int session_activate(Session
*s
) {
607 unsigned num_pending
;
615 if (s
->seat
->active
== s
)
618 /* on seats with VTs, we let VTs manage session-switching */
619 if (seat_has_vts(s
->seat
)) {
623 return chvt(s
->vtnr
);
626 /* On seats without VTs, we implement session-switching in logind. We
627 * try to pause all session-devices and wait until the session
628 * controller acknowledged them. Once all devices are asleep, we simply
629 * switch the active session and be done.
630 * We save the session we want to switch to in seat->pending_switch and
631 * seat_complete_switch() will perform the final switch. */
633 s
->seat
->pending_switch
= s
;
635 /* if no devices are running, immediately perform the session switch */
636 num_pending
= session_device_try_pause_all(s
);
638 seat_complete_switch(s
->seat
);
643 static int session_start_scope(Session
*s
, sd_bus_message
*properties
, sd_bus_error
*error
) {
650 _cleanup_free_
char *scope
= NULL
;
651 const char *description
;
653 s
->scope_job
= mfree(s
->scope_job
);
655 scope
= strjoin("session-", s
->id
, ".scope");
659 description
= strjoina("Session ", s
->id
, " of user ", s
->user
->user_record
->user_name
);
661 r
= manager_start_scope(
667 /* These two have StopWhenUnneeded= set, hence add a dep towards them */
668 STRV_MAKE(s
->user
->runtime_dir_service
,
670 /* And order us after some more */
671 STRV_MAKE("systemd-logind.service",
672 "systemd-user-sessions.service",
673 s
->user
->runtime_dir_service
,
675 user_record_home_directory(s
->user
->user_record
),
680 return log_error_errno(r
, "Failed to start session scope %s: %s",
681 scope
, bus_error_message(error
, r
));
683 s
->scope
= TAKE_PTR(scope
);
686 (void) hashmap_put(s
->manager
->session_units
, s
->scope
, s
);
691 int session_start(Session
*s
, sd_bus_message
*properties
, sd_bus_error
*error
) {
705 r
= user_start(s
->user
);
709 r
= session_start_scope(s
, properties
, error
);
713 log_struct(s
->class == SESSION_BACKGROUND
? LOG_DEBUG
: LOG_INFO
,
714 "MESSAGE_ID=" SD_MESSAGE_SESSION_START_STR
,
715 "SESSION_ID=%s", s
->id
,
716 "USER_ID=%s", s
->user
->user_record
->user_name
,
717 "LEADER="PID_FMT
, s
->leader
,
718 LOG_MESSAGE("New session %s of user %s.", s
->id
, s
->user
->user_record
->user_name
));
720 if (!dual_timestamp_is_set(&s
->timestamp
))
721 dual_timestamp_get(&s
->timestamp
);
724 seat_read_active_vt(s
->seat
);
728 user_elect_display(s
->user
);
737 session_send_signal(s
, true);
738 user_send_changed(s
->user
, "Display", NULL
);
740 if (s
->seat
->active
== s
)
741 seat_send_changed(s
->seat
, "ActiveSession", NULL
);
747 static int session_stop_scope(Session
*s
, bool force
) {
748 _cleanup_(sd_bus_error_free
) sd_bus_error error
= SD_BUS_ERROR_NULL
;
756 /* Let's always abandon the scope first. This tells systemd that we are not interested anymore, and everything
757 * that is left in the scope is "left-over". Informing systemd about this has the benefit that it will log
758 * when killing any processes left after this point. */
759 r
= manager_abandon_scope(s
->manager
, s
->scope
, &error
);
761 log_warning_errno(r
, "Failed to abandon session scope, ignoring: %s", bus_error_message(&error
, r
));
762 sd_bus_error_free(&error
);
765 s
->scope_job
= mfree(s
->scope_job
);
767 /* Optionally, let's kill everything that's left now. */
769 (s
->user
->user_record
->kill_processes
!= 0 &&
770 (s
->user
->user_record
->kill_processes
> 0 ||
771 manager_shall_kill(s
->manager
, s
->user
->user_record
->user_name
)))) {
773 r
= manager_stop_unit(s
->manager
, s
->scope
, &error
, &s
->scope_job
);
776 return log_error_errno(r
, "Failed to stop session scope: %s", bus_error_message(&error
, r
));
778 log_warning_errno(r
, "Failed to stop session scope, ignoring: %s", bus_error_message(&error
, r
));
782 /* With no killing, this session is allowed to persist in "closing" state indefinitely.
783 * Therefore session stop and session removal may be two distinct events.
784 * Session stop is quite significant on its own, let's log it. */
785 log_struct(s
->class == SESSION_BACKGROUND
? LOG_DEBUG
: LOG_INFO
,
786 "SESSION_ID=%s", s
->id
,
787 "USER_ID=%s", s
->user
->user_record
->user_name
,
788 "LEADER="PID_FMT
, s
->leader
,
789 LOG_MESSAGE("Session %s logged out. Waiting for processes to exit.", s
->id
));
795 int session_stop(Session
*s
, bool force
) {
800 /* This is called whenever we begin with tearing down a session record. It's called in four cases: explicit API
801 * request via the bus (either directly for the session object or for the seat or user object this session
802 * belongs to; 'force' is true), or due to automatic GC (i.e. scope vanished; 'force' is false), or because the
803 * session FIFO saw an EOF ('force' is false), or because the release timer hit ('force' is false). */
812 s
->timer_event_source
= sd_event_source_unref(s
->timer_event_source
);
815 seat_evict_position(s
->seat
, s
);
817 /* We are going down, don't care about FIFOs anymore */
818 session_remove_fifo(s
);
821 r
= session_stop_scope(s
, force
);
825 user_elect_display(s
->user
);
833 int session_finalize(Session
*s
) {
842 log_struct(s
->class == SESSION_BACKGROUND
? LOG_DEBUG
: LOG_INFO
,
843 "MESSAGE_ID=" SD_MESSAGE_SESSION_STOP_STR
,
844 "SESSION_ID=%s", s
->id
,
845 "USER_ID=%s", s
->user
->user_record
->user_name
,
846 "LEADER="PID_FMT
, s
->leader
,
847 LOG_MESSAGE("Removed session %s.", s
->id
));
849 s
->timer_event_source
= sd_event_source_unref(s
->timer_event_source
);
852 seat_evict_position(s
->seat
, s
);
854 /* Kill session devices */
855 while ((sd
= hashmap_first(s
->devices
)))
856 session_device_free(sd
);
858 (void) unlink(s
->state_file
);
859 session_add_to_gc_queue(s
);
860 user_add_to_gc_queue(s
->user
);
863 session_send_signal(s
, false);
868 if (s
->seat
->active
== s
)
869 seat_set_active(s
->seat
, NULL
);
875 user_send_changed(s
->user
, "Display", NULL
);
880 static int release_timeout_callback(sd_event_source
*es
, uint64_t usec
, void *userdata
) {
881 Session
*s
= userdata
;
886 session_stop(s
, false);
890 int session_release(Session
*s
) {
893 if (!s
->started
|| s
->stopping
)
896 if (s
->timer_event_source
)
899 return sd_event_add_time_relative(
901 &s
->timer_event_source
,
904 release_timeout_callback
, s
);
907 bool session_is_active(Session
*s
) {
913 return s
->seat
->active
== s
;
916 static int get_tty_atime(const char *tty
, usec_t
*atime
) {
917 _cleanup_free_
char *p
= NULL
;
923 if (!path_is_absolute(tty
)) {
924 p
= path_join("/dev", tty
);
929 } else if (!path_startswith(tty
, "/dev/"))
932 if (lstat(tty
, &st
) < 0)
935 *atime
= timespec_load(&st
.st_atim
);
939 static int get_process_ctty_atime(pid_t pid
, usec_t
*atime
) {
940 _cleanup_free_
char *p
= NULL
;
946 r
= get_ctty(pid
, NULL
, &p
);
950 return get_tty_atime(p
, atime
);
953 int session_get_idle_hint(Session
*s
, dual_timestamp
*t
) {
959 /* Graphical sessions have an explicit idle hint */
960 if (SESSION_TYPE_IS_GRAPHICAL(s
->type
)) {
962 *t
= s
->idle_hint_timestamp
;
967 /* For sessions with an explicitly configured tty, let's check its atime */
969 r
= get_tty_atime(s
->tty
, &atime
);
974 /* For sessions with a leader but no explicitly configured tty, let's check the controlling tty of
976 if (pid_is_valid(s
->leader
)) {
977 r
= get_process_ctty_atime(s
->leader
, &atime
);
983 *t
= DUAL_TIMESTAMP_NULL
;
989 dual_timestamp_from_realtime(t
, atime
);
991 if (s
->manager
->idle_action_usec
<= 0)
994 return usec_add(atime
, s
->manager
->idle_action_usec
) <= now(CLOCK_REALTIME
);
997 int session_set_idle_hint(Session
*s
, bool b
) {
1000 if (!SESSION_TYPE_IS_GRAPHICAL(s
->type
))
1003 if (s
->idle_hint
== b
)
1007 dual_timestamp_get(&s
->idle_hint_timestamp
);
1009 session_send_changed(s
, "IdleHint", "IdleSinceHint", "IdleSinceHintMonotonic", NULL
);
1012 seat_send_changed(s
->seat
, "IdleHint", "IdleSinceHint", "IdleSinceHintMonotonic", NULL
);
1014 user_send_changed(s
->user
, "IdleHint", "IdleSinceHint", "IdleSinceHintMonotonic", NULL
);
1015 manager_send_changed(s
->manager
, "IdleHint", "IdleSinceHint", "IdleSinceHintMonotonic", NULL
);
1020 int session_get_locked_hint(Session
*s
) {
1023 return s
->locked_hint
;
1026 void session_set_locked_hint(Session
*s
, bool b
) {
1029 if (s
->locked_hint
== b
)
1034 session_send_changed(s
, "LockedHint", NULL
);
1037 void session_set_type(Session
*s
, SessionType t
) {
1046 session_send_changed(s
, "Type", NULL
);
1049 static int session_dispatch_fifo(sd_event_source
*es
, int fd
, uint32_t revents
, void *userdata
) {
1050 Session
*s
= userdata
;
1053 assert(s
->fifo_fd
== fd
);
1055 /* EOF on the FIFO means the session died abnormally. */
1057 session_remove_fifo(s
);
1058 session_stop(s
, false);
1063 int session_create_fifo(Session
*s
) {
1069 if (!s
->fifo_path
) {
1070 r
= mkdir_safe_label("/run/systemd/sessions", 0755, 0, 0, MKDIR_WARN_MODE
);
1074 s
->fifo_path
= strjoin("/run/systemd/sessions/", s
->id
, ".ref");
1078 if (mkfifo(s
->fifo_path
, 0600) < 0 && errno
!= EEXIST
)
1082 /* Open reading side */
1083 if (s
->fifo_fd
< 0) {
1084 s
->fifo_fd
= open(s
->fifo_path
, O_RDONLY
|O_CLOEXEC
|O_NONBLOCK
);
1089 if (!s
->fifo_event_source
) {
1090 r
= sd_event_add_io(s
->manager
->event
, &s
->fifo_event_source
, s
->fifo_fd
, 0, session_dispatch_fifo
, s
);
1094 /* Let's make sure we noticed dead sessions before we process new bus requests (which might create new
1096 r
= sd_event_source_set_priority(s
->fifo_event_source
, SD_EVENT_PRIORITY_NORMAL
-10);
1101 /* Open writing side */
1102 r
= open(s
->fifo_path
, O_WRONLY
|O_CLOEXEC
|O_NONBLOCK
);
1109 static void session_remove_fifo(Session
*s
) {
1112 s
->fifo_event_source
= sd_event_source_unref(s
->fifo_event_source
);
1113 s
->fifo_fd
= safe_close(s
->fifo_fd
);
1116 (void) unlink(s
->fifo_path
);
1117 s
->fifo_path
= mfree(s
->fifo_path
);
1121 bool session_may_gc(Session
*s
, bool drop_not_started
) {
1126 if (drop_not_started
&& !s
->started
)
1132 if (s
->fifo_fd
>= 0) {
1133 if (pipe_eof(s
->fifo_fd
) <= 0)
1138 _cleanup_(sd_bus_error_free
) sd_bus_error error
= SD_BUS_ERROR_NULL
;
1140 r
= manager_job_is_active(s
->manager
, s
->scope_job
, &error
);
1142 log_debug_errno(r
, "Failed to determine whether job '%s' is pending, ignoring: %s", s
->scope_job
, bus_error_message(&error
, r
));
1148 _cleanup_(sd_bus_error_free
) sd_bus_error error
= SD_BUS_ERROR_NULL
;
1150 r
= manager_unit_is_active(s
->manager
, s
->scope
, &error
);
1152 log_debug_errno(r
, "Failed to determine whether unit '%s' is active, ignoring: %s", s
->scope
, bus_error_message(&error
, r
));
1160 void session_add_to_gc_queue(Session
*s
) {
1166 LIST_PREPEND(gc_queue
, s
->manager
->session_gc_queue
, s
);
1167 s
->in_gc_queue
= true;
1170 SessionState
session_get_state(Session
*s
) {
1173 /* always check closing first */
1174 if (s
->stopping
|| s
->timer_event_source
)
1175 return SESSION_CLOSING
;
1177 if (s
->scope_job
|| s
->fifo_fd
< 0)
1178 return SESSION_OPENING
;
1180 if (session_is_active(s
))
1181 return SESSION_ACTIVE
;
1183 return SESSION_ONLINE
;
1186 int session_kill(Session
*s
, KillWho who
, int signo
) {
1192 return manager_kill_unit(s
->manager
, s
->scope
, who
, signo
, NULL
);
1195 static int session_open_vt(Session
*s
) {
1196 char path
[sizeof("/dev/tty") + DECIMAL_STR_MAX(s
->vtnr
)];
1204 sprintf(path
, "/dev/tty%u", s
->vtnr
);
1205 s
->vtfd
= open_terminal(path
, O_RDWR
| O_CLOEXEC
| O_NONBLOCK
| O_NOCTTY
);
1207 return log_error_errno(s
->vtfd
, "cannot open VT %s of session %s: %m", path
, s
->id
);
1212 static int session_prepare_vt(Session
*s
) {
1214 struct vt_mode mode
= {};
1219 vt
= session_open_vt(s
);
1223 r
= fchown(vt
, s
->user
->user_record
->uid
, -1);
1225 r
= log_error_errno(errno
,
1226 "Cannot change owner of /dev/tty%u: %m",
1231 r
= ioctl(vt
, KDSKBMODE
, K_OFF
);
1233 r
= log_error_errno(errno
,
1234 "Cannot set K_OFF on /dev/tty%u: %m",
1239 r
= ioctl(vt
, KDSETMODE
, KD_GRAPHICS
);
1241 r
= log_error_errno(errno
,
1242 "Cannot set KD_GRAPHICS on /dev/tty%u: %m",
1247 /* Oh, thanks to the VT layer, VT_AUTO does not work with KD_GRAPHICS.
1248 * So we need a dummy handler here which just acknowledges *all* VT
1249 * switch requests. */
1250 mode
.mode
= VT_PROCESS
;
1251 mode
.relsig
= SIGRTMIN
;
1252 mode
.acqsig
= SIGRTMIN
+ 1;
1253 r
= ioctl(vt
, VT_SETMODE
, &mode
);
1255 r
= log_error_errno(errno
,
1256 "Cannot set VT_PROCESS on /dev/tty%u: %m",
1264 session_restore_vt(s
);
1268 static void session_restore_vt(Session
*s
) {
1271 r
= vt_restore(s
->vtfd
);
1275 /* It might happen if the controlling process exited before or while we were
1276 * restoring the VT as it would leave the old file-descriptor in a hung-up
1277 * state. In this case let's retry with a fresh handle to the virtual terminal. */
1279 /* We do a little dance to avoid having the terminal be available
1280 * for reuse before we've cleaned it up. */
1281 old_fd
= TAKE_FD(s
->vtfd
);
1283 vt
= session_open_vt(s
);
1291 log_warning_errno(r
, "Failed to restore VT, ignoring: %m");
1293 s
->vtfd
= safe_close(s
->vtfd
);
1296 void session_leave_vt(Session
*s
) {
1301 /* This is called whenever we get a VT-switch signal from the kernel.
1302 * We acknowledge all of them unconditionally. Note that session are
1303 * free to overwrite those handlers and we only register them for
1304 * sessions with controllers. Legacy sessions are not affected.
1305 * However, if we switch from a non-legacy to a legacy session, we must
1306 * make sure to pause all device before acknowledging the switch. We
1307 * process the real switch only after we are notified via sysfs, so the
1308 * legacy session might have already started using the devices. If we
1309 * don't pause the devices before the switch, we might confuse the
1310 * session we switch to. */
1315 session_device_pause_all(s
);
1316 r
= vt_release(s
->vtfd
, false);
1318 log_debug_errno(r
, "Cannot release VT of session %s: %m", s
->id
);
1321 bool session_is_controller(Session
*s
, const char *sender
) {
1324 return streq_ptr(s
->controller
, sender
);
1327 static void session_release_controller(Session
*s
, bool notify
) {
1328 _cleanup_free_
char *name
= NULL
;
1334 name
= s
->controller
;
1336 /* By resetting the controller before releasing the devices, we won't
1337 * send notification signals. This avoids sending useless notifications
1338 * if the controller is released on disconnects. */
1340 s
->controller
= NULL
;
1342 while ((sd
= hashmap_first(s
->devices
)))
1343 session_device_free(sd
);
1345 s
->controller
= NULL
;
1346 s
->track
= sd_bus_track_unref(s
->track
);
1349 static int on_bus_track(sd_bus_track
*track
, void *userdata
) {
1350 Session
*s
= userdata
;
1355 session_drop_controller(s
);
1360 int session_set_controller(Session
*s
, const char *sender
, bool force
, bool prepare
) {
1361 _cleanup_free_
char *name
= NULL
;
1367 if (session_is_controller(s
, sender
))
1369 if (s
->controller
&& !force
)
1372 name
= strdup(sender
);
1376 s
->track
= sd_bus_track_unref(s
->track
);
1377 r
= sd_bus_track_new(s
->manager
->bus
, &s
->track
, on_bus_track
, s
);
1381 r
= sd_bus_track_add_name(s
->track
, name
);
1385 /* When setting a session controller, we forcibly mute the VT and set
1386 * it into graphics-mode. Applications can override that by changing
1387 * VT state after calling TakeControl(). However, this serves as a good
1388 * default and well-behaving controllers can now ignore VTs entirely.
1389 * Note that we reset the VT on ReleaseControl() and if the controller
1391 * If logind crashes/restarts, we restore the controller during restart
1392 * (without preparing the VT since the controller has probably overridden
1393 * VT state by now) or reset the VT in case it crashed/exited, too. */
1395 r
= session_prepare_vt(s
);
1397 s
->track
= sd_bus_track_unref(s
->track
);
1402 session_release_controller(s
, true);
1403 s
->controller
= TAKE_PTR(name
);
1409 void session_drop_controller(Session
*s
) {
1415 s
->track
= sd_bus_track_unref(s
->track
);
1416 session_set_type(s
, s
->original_type
);
1417 session_release_controller(s
, false);
1419 session_restore_vt(s
);
1422 static const char* const session_state_table
[_SESSION_STATE_MAX
] = {
1423 [SESSION_OPENING
] = "opening",
1424 [SESSION_ONLINE
] = "online",
1425 [SESSION_ACTIVE
] = "active",
1426 [SESSION_CLOSING
] = "closing"
1429 DEFINE_STRING_TABLE_LOOKUP(session_state
, SessionState
);
1431 static const char* const session_type_table
[_SESSION_TYPE_MAX
] = {
1432 [SESSION_UNSPECIFIED
] = "unspecified",
1433 [SESSION_TTY
] = "tty",
1434 [SESSION_X11
] = "x11",
1435 [SESSION_WAYLAND
] = "wayland",
1436 [SESSION_MIR
] = "mir",
1437 [SESSION_WEB
] = "web",
1440 DEFINE_STRING_TABLE_LOOKUP(session_type
, SessionType
);
1442 static const char* const session_class_table
[_SESSION_CLASS_MAX
] = {
1443 [SESSION_USER
] = "user",
1444 [SESSION_GREETER
] = "greeter",
1445 [SESSION_LOCK_SCREEN
] = "lock-screen",
1446 [SESSION_BACKGROUND
] = "background"
1449 DEFINE_STRING_TABLE_LOOKUP(session_class
, SessionClass
);
1451 static const char* const kill_who_table
[_KILL_WHO_MAX
] = {
1452 [KILL_LEADER
] = "leader",
1456 DEFINE_STRING_TABLE_LOOKUP(kill_who
, KillWho
);
1458 static const char* const tty_validity_table
[_TTY_VALIDITY_MAX
] = {
1459 [TTY_FROM_PAM
] = "from-pam",
1460 [TTY_FROM_UTMP
] = "from-utmp",
1461 [TTY_UTMP_INCONSISTENT
] = "utmp-inconsistent",
1464 DEFINE_STRING_TABLE_LOOKUP(tty_validity
, TTYValidity
);