1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
4 This file is part of systemd.
6 Copyright 2011 Lennart Poettering
8 systemd is free software; you can redistribute it and/or modify it
9 under the terms of the GNU Lesser General Public License as published by
10 the Free Software Foundation; either version 2.1 of the License, or
11 (at your option) any later version.
13 systemd is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 Lesser General Public License for more details.
18 You should have received a copy of the GNU Lesser General Public License
19 along with systemd; If not, see <http://www.gnu.org/licenses/>.
28 #include <sys/ioctl.h>
32 #include "sd-messages.h"
36 #include "path-util.h"
40 #include "bus-error.h"
41 #include "logind-session.h"
43 #define RELEASE_USEC (20*USEC_PER_SEC)
45 static void session_remove_fifo(Session *s);
47 static unsigned long devt_hash_func(const void *p, const uint8_t hash_key[HASH_KEY_SIZE]) {
48 uint64_t u = *(const dev_t*)p;
50 return uint64_hash_func(&u, hash_key);
53 static int devt_compare_func(const void *_a, const void *_b) {
56 a = *(const dev_t*) _a;
57 b = *(const dev_t*) _b;
59 return a < b ? -1 : (a > b ? 1 : 0);
62 Session* session_new(Manager *m, const char *id) {
67 assert(session_id_valid(id));
73 s->state_file = strappend("/run/systemd/sessions/", id);
79 s->devices = hashmap_new(devt_hash_func, devt_compare_func);
86 s->id = basename(s->state_file);
88 if (hashmap_put(m->sessions, s->id, s) < 0) {
89 hashmap_free(s->devices);
102 void session_free(Session *s) {
108 LIST_REMOVE(gc_queue, s->manager->session_gc_queue, s);
110 s->timer_event_source = sd_event_source_unref(s->timer_event_source);
112 session_remove_fifo(s);
114 session_drop_controller(s);
116 while ((sd = hashmap_first(s->devices)))
117 session_device_free(sd);
119 hashmap_free(s->devices);
122 LIST_REMOVE(sessions_by_user, s->user->sessions, s);
124 if (s->user->display == s)
125 s->user->display = NULL;
129 if (s->seat->active == s)
130 s->seat->active = NULL;
131 if (s->seat->pending_switch == s)
132 s->seat->pending_switch = NULL;
134 seat_evict_position(s->seat, s);
135 LIST_REMOVE(sessions_by_seat, s->seat->sessions, s);
139 hashmap_remove(s->manager->session_units, s->scope);
145 sd_bus_message_unref(s->create_message);
149 free(s->remote_host);
150 free(s->remote_user);
154 hashmap_remove(s->manager->sessions, s->id);
156 s->vt_source = sd_event_source_unref(s->vt_source);
162 void session_set_user(Session *s, User *u) {
167 LIST_PREPEND(sessions_by_user, u->sessions, s);
170 int session_save(Session *s) {
171 _cleanup_free_ char *temp_path = NULL;
172 _cleanup_fclose_ FILE *f = NULL;
183 r = mkdir_safe_label("/run/systemd/sessions", 0755, 0, 0);
187 r = fopen_temporary(s->state_file, &f, &temp_path);
193 fchmod(fileno(f), 0644);
196 "# This is private data. Do not parse.\n"
204 session_is_active(s),
205 session_state_to_string(session_get_state(s)),
209 fprintf(f, "TYPE=%s\n", session_type_to_string(s->type));
212 fprintf(f, "CLASS=%s\n", session_class_to_string(s->class));
215 fprintf(f, "SCOPE=%s\n", s->scope);
218 fprintf(f, "SCOPE_JOB=%s\n", s->scope_job);
221 fprintf(f, "FIFO=%s\n", s->fifo_path);
224 fprintf(f, "SEAT=%s\n", s->seat->id);
227 fprintf(f, "TTY=%s\n", s->tty);
230 fprintf(f, "DISPLAY=%s\n", s->display);
233 fprintf(f, "REMOTE_HOST=%s\n", s->remote_host);
236 fprintf(f, "REMOTE_USER=%s\n", s->remote_user);
239 fprintf(f, "SERVICE=%s\n", s->service);
242 fprintf(f, "DESKTOP=%s\n", s->desktop);
244 if (s->seat && seat_has_vts(s->seat))
245 fprintf(f, "VTNR=%u\n", s->vtnr);
248 fprintf(f, "POS=%u\n", s->pos);
251 fprintf(f, "LEADER="PID_FMT"\n", s->leader);
254 fprintf(f, "AUDIT=%"PRIu32"\n", s->audit_id);
256 if (dual_timestamp_is_set(&s->timestamp))
258 "REALTIME="USEC_FMT"\n"
259 "MONOTONIC="USEC_FMT"\n",
260 s->timestamp.realtime,
261 s->timestamp.monotonic);
264 fprintf(f, "CONTROLLER=%s\n", s->controller);
268 if (ferror(f) || rename(temp_path, s->state_file) < 0) {
270 unlink(s->state_file);
276 log_error("Failed to save session data %s: %s", s->state_file, strerror(-r));
281 int session_load(Session *s) {
282 _cleanup_free_ char *remote = NULL,
298 r = parse_env_file(s->state_file, NEWLINE,
301 "SCOPE_JOB", &s->scope_job,
302 "FIFO", &s->fifo_path,
305 "DISPLAY", &s->display,
306 "REMOTE_HOST", &s->remote_host,
307 "REMOTE_USER", &s->remote_user,
308 "SERVICE", &s->service,
309 "DESKTOP", &s->desktop,
316 "REALTIME", &realtime,
317 "MONOTONIC", &monotonic,
318 "CONTROLLER", &controller,
322 log_error("Failed to read %s: %s", s->state_file, strerror(-r));
331 log_error("UID not specified for session %s", s->id);
335 r = parse_uid(uid, &u);
337 log_error("Failed to parse UID value %s for session %s.", uid, s->id);
341 user = hashmap_get(s->manager->users, ULONG_TO_PTR((unsigned long) u));
343 log_error("User of session %s not known.", s->id);
347 session_set_user(s, user);
351 k = parse_boolean(remote);
357 safe_atou(vtnr, &s->vtnr);
359 if (seat && !s->seat) {
362 o = hashmap_get(s->manager->seats, seat);
364 r = seat_attach_session(o, s);
366 log_error("Cannot attach session %s to seat %s", s->id, seat);
369 if (!s->seat || !seat_has_vts(s->seat))
372 if (pos && s->seat) {
375 safe_atou(pos, &npos);
376 seat_claim_position(s->seat, s, npos);
380 k = parse_pid(leader, &s->leader);
382 audit_session_from_pid(s->leader, &s->audit_id);
388 t = session_type_from_string(type);
396 c = session_class_from_string(class);
404 /* If we open an unopened pipe for reading we will not
405 get an EOF. to trigger an EOF we hence open it for
406 reading, but close it right-away which then will
409 fd = session_create_fifo(s);
414 unsigned long long l;
415 if (sscanf(realtime, "%llu", &l) > 0)
416 s->timestamp.realtime = l;
420 unsigned long long l;
421 if (sscanf(monotonic, "%llu", &l) > 0)
422 s->timestamp.monotonic = l;
426 if (bus_name_has_owner(s->manager->bus, controller, NULL) > 0)
427 session_set_controller(s, controller, false);
429 session_restore_vt(s);
435 int session_activate(Session *s) {
436 unsigned int num_pending;
444 if (s->seat->active == s)
447 /* on seats with VTs, we let VTs manage session-switching */
448 if (seat_has_vts(s->seat)) {
452 return chvt(s->vtnr);
455 /* On seats without VTs, we implement session-switching in logind. We
456 * try to pause all session-devices and wait until the session
457 * controller acknowledged them. Once all devices are asleep, we simply
458 * switch the active session and be done.
459 * We save the session we want to switch to in seat->pending_switch and
460 * seat_complete_switch() will perform the final switch. */
462 s->seat->pending_switch = s;
464 /* if no devices are running, immediately perform the session switch */
465 num_pending = session_device_try_pause_all(s);
467 seat_complete_switch(s->seat);
472 static int session_start_scope(Session *s) {
477 assert(s->user->slice);
480 _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
481 _cleanup_free_ char *description = NULL;
482 char *scope, *job = NULL;
484 description = strjoin("Session ", s->id, " of user ", s->user->name, NULL);
488 scope = strjoin("session-", s->id, ".scope", NULL);
492 r = manager_start_scope(s->manager, scope, s->leader, s->user->slice, description, "systemd-logind.service", "systemd-user-sessions.service", &error, &job);
494 log_error("Failed to start session scope %s: %s %s",
495 scope, bus_error_message(&error, r), error.name);
507 hashmap_put(s->manager->session_units, s->scope, s);
512 int session_start(Session *s) {
523 r = user_start(s->user);
528 r = session_start_scope(s);
532 log_struct(s->class == SESSION_BACKGROUND ? LOG_DEBUG : LOG_INFO,
533 MESSAGE_ID(SD_MESSAGE_SESSION_START),
534 "SESSION_ID=%s", s->id,
535 "USER_ID=%s", s->user->name,
536 "LEADER=%lu", (unsigned long) s->leader,
537 "MESSAGE=New session %s of user %s.", s->id, s->user->name,
540 if (!dual_timestamp_is_set(&s->timestamp))
541 dual_timestamp_get(&s->timestamp);
544 seat_read_active_vt(s->seat);
555 session_send_signal(s, true);
556 user_send_changed(s->user, "Sessions", NULL);
558 if (s->seat->active == s)
559 seat_send_changed(s->seat, "Sessions", "ActiveSession", NULL);
561 seat_send_changed(s->seat, "Sessions", NULL);
567 static int session_stop_scope(Session *s, bool force) {
568 _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
577 if (force || manager_shall_kill(s->manager, s->user->name)) {
578 r = manager_stop_unit(s->manager, s->scope, &error, &job);
580 log_error("Failed to stop session scope: %s", bus_error_message(&error, r));
587 r = manager_abandon_scope(s->manager, s->scope, &error);
589 log_error("Failed to abandon session scope: %s", bus_error_message(&error, r));
597 int session_stop(Session *s, bool force) {
605 s->timer_event_source = sd_event_source_unref(s->timer_event_source);
607 /* We are going down, don't care about FIFOs anymore */
608 session_remove_fifo(s);
611 r = session_stop_scope(s, force);
621 int session_finalize(Session *s) {
631 log_struct(s->class == SESSION_BACKGROUND ? LOG_DEBUG : LOG_INFO,
632 MESSAGE_ID(SD_MESSAGE_SESSION_STOP),
633 "SESSION_ID=%s", s->id,
634 "USER_ID=%s", s->user->name,
635 "LEADER=%lu", (unsigned long) s->leader,
636 "MESSAGE=Removed session %s.", s->id,
639 s->timer_event_source = sd_event_source_unref(s->timer_event_source);
641 /* Kill session devices */
642 while ((sd = hashmap_first(s->devices)))
643 session_device_free(sd);
645 unlink(s->state_file);
646 session_add_to_gc_queue(s);
647 user_add_to_gc_queue(s->user);
650 session_send_signal(s, false);
655 if (s->seat->active == s)
656 seat_set_active(s->seat, NULL);
659 seat_send_changed(s->seat, "Sessions", NULL);
663 user_send_changed(s->user, "Sessions", NULL);
668 static int release_timeout_callback(sd_event_source *es, uint64_t usec, void *userdata) {
669 Session *s = userdata;
674 session_stop(s, false);
678 void session_release(Session *s) {
681 if (!s->started || s->stopping)
684 if (!s->timer_event_source)
685 sd_event_add_monotonic(s->manager->event, &s->timer_event_source, now(CLOCK_MONOTONIC) + RELEASE_USEC, 0, release_timeout_callback, s);
688 bool session_is_active(Session *s) {
694 return s->seat->active == s;
697 static int get_tty_atime(const char *tty, usec_t *atime) {
698 _cleanup_free_ char *p = NULL;
704 if (!path_is_absolute(tty)) {
705 p = strappend("/dev/", tty);
710 } else if (!path_startswith(tty, "/dev/"))
713 if (lstat(tty, &st) < 0)
716 *atime = timespec_load(&st.st_atim);
720 static int get_process_ctty_atime(pid_t pid, usec_t *atime) {
721 _cleanup_free_ char *p = NULL;
727 r = get_ctty(pid, NULL, &p);
731 return get_tty_atime(p, atime);
734 int session_get_idle_hint(Session *s, dual_timestamp *t) {
740 /* Explicit idle hint is set */
743 *t = s->idle_hint_timestamp;
748 /* Graphical sessions should really implement a real
753 /* For sessions with an explicitly configured tty, let's check
756 r = get_tty_atime(s->tty, &atime);
761 /* For sessions with a leader but no explicitly configured
762 * tty, let's check the controlling tty of the leader */
764 r = get_process_ctty_atime(s->leader, &atime);
771 *t = s->idle_hint_timestamp;
777 dual_timestamp_from_realtime(t, atime);
779 n = now(CLOCK_REALTIME);
781 if (s->manager->idle_action_usec <= 0)
784 return atime + s->manager->idle_action_usec <= n;
787 void session_set_idle_hint(Session *s, bool b) {
790 if (s->idle_hint == b)
794 dual_timestamp_get(&s->idle_hint_timestamp);
796 session_send_changed(s, "IdleHint", "IdleSinceHint", "IdleSinceHintMonotonic", NULL);
799 seat_send_changed(s->seat, "IdleHint", "IdleSinceHint", "IdleSinceHintMonotonic", NULL);
801 user_send_changed(s->user, "IdleHint", "IdleSinceHint", "IdleSinceHintMonotonic", NULL);
802 manager_send_changed(s->manager, "IdleHint", "IdleSinceHint", "IdleSinceHintMonotonic", NULL);
805 static int session_dispatch_fifo(sd_event_source *es, int fd, uint32_t revents, void *userdata) {
806 Session *s = userdata;
809 assert(s->fifo_fd == fd);
811 /* EOF on the FIFO means the session died abnormally. */
813 session_remove_fifo(s);
814 session_stop(s, false);
819 int session_create_fifo(Session *s) {
826 r = mkdir_safe_label("/run/systemd/sessions", 0755, 0, 0);
830 if (asprintf(&s->fifo_path, "/run/systemd/sessions/%s.ref", s->id) < 0)
833 if (mkfifo(s->fifo_path, 0600) < 0 && errno != EEXIST)
837 /* Open reading side */
838 if (s->fifo_fd < 0) {
839 s->fifo_fd = open(s->fifo_path, O_RDONLY|O_CLOEXEC|O_NDELAY);
845 if (!s->fifo_event_source) {
846 r = sd_event_add_io(s->manager->event, &s->fifo_event_source, s->fifo_fd, 0, session_dispatch_fifo, s);
850 r = sd_event_source_set_priority(s->fifo_event_source, SD_EVENT_PRIORITY_IDLE);
855 /* Open writing side */
856 r = open(s->fifo_path, O_WRONLY|O_CLOEXEC|O_NDELAY);
863 static void session_remove_fifo(Session *s) {
866 s->fifo_event_source = sd_event_source_unref(s->fifo_event_source);
867 s->fifo_fd = safe_close(s->fifo_fd);
870 unlink(s->fifo_path);
876 bool session_check_gc(Session *s, bool drop_not_started) {
879 if (drop_not_started && !s->started)
885 if (s->fifo_fd >= 0) {
886 if (pipe_eof(s->fifo_fd) <= 0)
890 if (s->scope_job && manager_job_is_active(s->manager, s->scope_job))
893 if (s->scope && manager_unit_is_active(s->manager, s->scope))
899 void session_add_to_gc_queue(Session *s) {
905 LIST_PREPEND(gc_queue, s->manager->session_gc_queue, s);
906 s->in_gc_queue = true;
909 SessionState session_get_state(Session *s) {
912 /* always check closing first */
913 if (s->stopping || s->timer_event_source)
914 return SESSION_CLOSING;
916 if (s->scope_job || s->fifo_fd < 0)
917 return SESSION_OPENING;
919 if (session_is_active(s))
920 return SESSION_ACTIVE;
922 return SESSION_ONLINE;
925 int session_kill(Session *s, KillWho who, int signo) {
931 return manager_kill_unit(s->manager, s->scope, who, signo, NULL);
934 static int session_open_vt(Session *s) {
935 char path[sizeof("/dev/tty") + DECIMAL_STR_MAX(s->vtnr)];
943 sprintf(path, "/dev/tty%u", s->vtnr);
944 s->vtfd = open(path, O_RDWR | O_CLOEXEC | O_NONBLOCK | O_NOCTTY);
946 log_error("cannot open VT %s of session %s: %m", path, s->id);
953 static int session_vt_fn(sd_event_source *source, const struct signalfd_siginfo *si, void *data) {
957 ioctl(s->vtfd, VT_RELDISP, 1);
962 void session_mute_vt(Session *s) {
964 struct vt_mode mode = { 0 };
967 vt = session_open_vt(s);
971 r = ioctl(vt, KDSKBMODE, K_OFF);
975 r = ioctl(vt, KDSETMODE, KD_GRAPHICS);
980 sigaddset(&mask, SIGUSR1);
981 sigprocmask(SIG_BLOCK, &mask, NULL);
983 r = sd_event_add_signal(s->manager->event, &s->vt_source, SIGUSR1, session_vt_fn, s);
987 /* Oh, thanks to the VT layer, VT_AUTO does not work with KD_GRAPHICS.
988 * So we need a dummy handler here which just acknowledges *all* VT
989 * switch requests. */
990 mode.mode = VT_PROCESS;
991 mode.relsig = SIGUSR1;
992 mode.acqsig = SIGUSR1;
993 r = ioctl(vt, VT_SETMODE, &mode);
1000 log_error("cannot mute VT %u for session %s (%d/%d)", s->vtnr, s->id, r, errno);
1001 session_restore_vt(s);
1004 void session_restore_vt(Session *s) {
1005 _cleanup_free_ char *utf8 = NULL;
1006 int vt, kb = K_XLATE;
1007 struct vt_mode mode = { 0 };
1009 vt = session_open_vt(s);
1013 s->vt_source = sd_event_source_unref(s->vt_source);
1015 ioctl(vt, KDSETMODE, KD_TEXT);
1017 if (read_one_line_file("/sys/module/vt/parameters/default_utf8", &utf8) >= 0 && *utf8 == '1')
1020 ioctl(vt, KDSKBMODE, kb);
1022 mode.mode = VT_AUTO;
1023 ioctl(vt, VT_SETMODE, &mode);
1025 s->vtfd = safe_close(s->vtfd);
1028 bool session_is_controller(Session *s, const char *sender) {
1031 return streq_ptr(s->controller, sender);
1034 static void session_swap_controller(Session *s, char *name) {
1037 if (s->controller) {
1038 manager_drop_busname(s->manager, s->controller);
1039 free(s->controller);
1040 s->controller = NULL;
1042 /* Drop all devices as they're now unused. Do that after the
1043 * controller is released to avoid sending out useles
1045 while ((sd = hashmap_first(s->devices)))
1046 session_device_free(sd);
1049 session_restore_vt(s);
1052 s->controller = name;
1056 int session_set_controller(Session *s, const char *sender, bool force) {
1063 if (session_is_controller(s, sender))
1065 if (s->controller && !force)
1072 r = manager_watch_busname(s->manager, sender);
1078 session_swap_controller(s, t);
1080 /* When setting a session controller, we forcibly mute the VT and set
1081 * it into graphics-mode. Applications can override that by changing
1082 * VT state after calling TakeControl(). However, this serves as a good
1083 * default and well-behaving controllers can now ignore VTs entirely.
1084 * Note that we reset the VT on ReleaseControl() and if the controller
1086 * If logind crashes/restarts, we restore the controller during restart
1087 * or reset the VT in case it crashed/exited, too. */
1093 void session_drop_controller(Session *s) {
1099 session_swap_controller(s, NULL);
1102 static const char* const session_state_table[_SESSION_STATE_MAX] = {
1103 [SESSION_OPENING] = "opening",
1104 [SESSION_ONLINE] = "online",
1105 [SESSION_ACTIVE] = "active",
1106 [SESSION_CLOSING] = "closing"
1109 DEFINE_STRING_TABLE_LOOKUP(session_state, SessionState);
1111 static const char* const session_type_table[_SESSION_TYPE_MAX] = {
1112 [SESSION_UNSPECIFIED] = "unspecified",
1113 [SESSION_TTY] = "tty",
1114 [SESSION_X11] = "x11",
1115 [SESSION_WAYLAND] = "wayland",
1118 DEFINE_STRING_TABLE_LOOKUP(session_type, SessionType);
1120 static const char* const session_class_table[_SESSION_CLASS_MAX] = {
1121 [SESSION_USER] = "user",
1122 [SESSION_GREETER] = "greeter",
1123 [SESSION_LOCK_SCREEN] = "lock-screen",
1124 [SESSION_BACKGROUND] = "background"
1127 DEFINE_STRING_TABLE_LOOKUP(session_class, SessionClass);
1129 static const char* const kill_who_table[_KILL_WHO_MAX] = {
1130 [KILL_LEADER] = "leader",
1134 DEFINE_STRING_TABLE_LOOKUP(kill_who, KillWho);