1 /* SPDX-License-Identifier: LGPL-2.1+ */
3 This file is part of systemd.
5 Copyright 2011 Lennart Poettering
11 #include <sys/inotify.h>
16 #include "alloc-util.h"
17 #include "cgroup-util.h"
18 #include "dirent-util.h"
22 #include "format-util.h"
24 #include "hostname-util.h"
26 #include "login-util.h"
28 #include "parse-util.h"
29 #include "path-util.h"
30 #include "socket-util.h"
31 #include "string-util.h"
33 #include "user-util.h"
38 * invalid input parameters → -EINVAL
40 * process does not exist → -ESRCH
41 * cgroup does not exist → -ENOENT
42 * machine, session does not exist → -ENXIO
43 * requested metadata on object is missing → -ENODATA
46 _public_ int sd_pid_get_session(pid_t pid, char **session) {
49 assert_return(pid >= 0, -EINVAL);
50 assert_return(session, -EINVAL);
52 r = cg_pid_get_session(pid, session);
53 return IN_SET(r, -ENXIO, -ENOMEDIUM) ? -ENODATA : r;
56 _public_ int sd_pid_get_unit(pid_t pid, char **unit) {
57 #if 0 /// UNNEEDED by elogind
61 assert_return(pid >= 0, -EINVAL);
62 assert_return(unit, -EINVAL);
64 #if 0 /// elogind does not support systemd units
65 r = cg_pid_get_unit(pid, unit);
66 return IN_SET(r, -ENXIO, -ENOMEDIUM) ? -ENODATA : r;
72 _public_ int sd_pid_get_user_unit(pid_t pid, char **unit) {
73 #if 0 /// UNNEEDED by elogind
77 assert_return(pid >= 0, -EINVAL);
78 assert_return(unit, -EINVAL);
80 #if 0 /// elogind does not support systemd units
81 r = cg_pid_get_user_unit(pid, unit);
82 return IN_SET(r, -ENXIO, -ENOMEDIUM) ? -ENODATA : r;
88 _public_ int sd_pid_get_machine_name(pid_t pid, char **name) {
89 #if 0 /// UNNEEDED by elogind
93 assert_return(pid >= 0, -EINVAL);
94 assert_return(name, -EINVAL);
96 #if 0 /// elogind does not support systemd units
97 r = cg_pid_get_machine_name(pid, name);
98 return IN_SET(r, -ENXIO, -ENOMEDIUM) ? -ENODATA : r;
104 _public_ int sd_pid_get_slice(pid_t pid, char **slice) {
107 assert_return(pid >= 0, -EINVAL);
108 assert_return(slice, -EINVAL);
110 r = cg_pid_get_slice(pid, slice);
111 return IN_SET(r, -ENXIO, -ENOMEDIUM) ? -ENODATA : r;
114 _public_ int sd_pid_get_user_slice(pid_t pid, char **slice) {
117 assert_return(pid >= 0, -EINVAL);
118 assert_return(slice, -EINVAL);
120 r = cg_pid_get_user_slice(pid, slice);
121 return IN_SET(r, -ENXIO, -ENOMEDIUM) ? -ENODATA : r;
124 _public_ int sd_pid_get_owner_uid(pid_t pid, uid_t *uid) {
127 assert_return(pid >= 0, -EINVAL);
128 assert_return(uid, -EINVAL);
130 r = cg_pid_get_owner_uid(pid, uid);
131 return IN_SET(r, -ENXIO, -ENOMEDIUM) ? -ENODATA : r;
134 _public_ int sd_pid_get_cgroup(pid_t pid, char **cgroup) {
138 assert_return(pid >= 0, -EINVAL);
139 assert_return(cgroup, -EINVAL);
141 r = cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, pid, &c);
145 /* The internal APIs return the empty string for the root
146 * cgroup, let's return the "/" in the public APIs instead, as
147 * that's easier and less ambiguous for people to grok. */
160 _public_ int sd_peer_get_session(int fd, char **session) {
161 struct ucred ucred = {};
164 assert_return(fd >= 0, -EBADF);
165 assert_return(session, -EINVAL);
167 r = getpeercred(fd, &ucred);
171 return cg_pid_get_session(ucred.pid, session);
174 _public_ int sd_peer_get_owner_uid(int fd, uid_t *uid) {
178 assert_return(fd >= 0, -EBADF);
179 assert_return(uid, -EINVAL);
181 r = getpeercred(fd, &ucred);
185 return cg_pid_get_owner_uid(ucred.pid, uid);
188 _public_ int sd_peer_get_unit(int fd, char **unit) {
192 assert_return(fd >= 0, -EBADF);
193 assert_return(unit, -EINVAL);
195 r = getpeercred(fd, &ucred);
199 #if 0 /// elogind does not support systemd units
200 return cg_pid_get_unit(ucred.pid, unit);
206 _public_ int sd_peer_get_user_unit(int fd, char **unit) {
210 assert_return(fd >= 0, -EBADF);
211 assert_return(unit, -EINVAL);
213 r = getpeercred(fd, &ucred);
217 #if 0 /// elogind does not support systemd units
218 return cg_pid_get_user_unit(ucred.pid, unit);
224 _public_ int sd_peer_get_machine_name(int fd, char **machine) {
228 assert_return(fd >= 0, -EBADF);
229 assert_return(machine, -EINVAL);
231 r = getpeercred(fd, &ucred);
235 #if 0 /// elogind does not support systemd units
236 return cg_pid_get_machine_name(ucred.pid, machine);
242 _public_ int sd_peer_get_slice(int fd, char **slice) {
246 assert_return(fd >= 0, -EBADF);
247 assert_return(slice, -EINVAL);
249 r = getpeercred(fd, &ucred);
253 return cg_pid_get_slice(ucred.pid, slice);
256 _public_ int sd_peer_get_user_slice(int fd, char **slice) {
260 assert_return(fd >= 0, -EBADF);
261 assert_return(slice, -EINVAL);
263 r = getpeercred(fd, &ucred);
267 return cg_pid_get_user_slice(ucred.pid, slice);
270 _public_ int sd_peer_get_cgroup(int fd, char **cgroup) {
274 assert_return(fd >= 0, -EBADF);
275 assert_return(cgroup, -EINVAL);
277 r = getpeercred(fd, &ucred);
281 return sd_pid_get_cgroup(ucred.pid, cgroup);
284 static int file_of_uid(uid_t uid, char **p) {
286 assert_return(uid_is_valid(uid), -EINVAL);
289 if (asprintf(p, "/run/systemd/users/" UID_FMT, uid) < 0)
295 _public_ int sd_uid_get_state(uid_t uid, char**state) {
296 _cleanup_free_ char *p = NULL;
300 assert_return(state, -EINVAL);
302 r = file_of_uid(uid, &p);
306 r = parse_env_file(NULL, p, NEWLINE, "STATE", &s, NULL);
309 s = strdup("offline");
327 _public_ int sd_uid_get_display(uid_t uid, char **session) {
328 _cleanup_free_ char *p = NULL, *s = NULL;
331 assert_return(session, -EINVAL);
333 r = file_of_uid(uid, &p);
337 r = parse_env_file(NULL, p, NEWLINE, "DISPLAY", &s, NULL);
345 *session = TAKE_PTR(s);
350 static int file_of_seat(const char *seat, char **_p) {
357 if (!filename_is_valid(seat))
360 p = strappend("/run/systemd/seats/", seat);
362 _cleanup_free_ char *buf = NULL;
364 r = sd_session_get_seat(NULL, &buf);
368 p = strappend("/run/systemd/seats/", buf);
378 _public_ int sd_uid_is_on_seat(uid_t uid, int require_active, const char *seat) {
379 _cleanup_free_ char *t = NULL, *s = NULL, *p = NULL;
382 const char *word, *variable, *state;
384 assert_return(uid_is_valid(uid), -EINVAL);
386 r = file_of_seat(seat, &p);
390 variable = require_active ? "ACTIVE_UID" : "UIDS";
392 r = parse_env_file(NULL, p, NEWLINE, variable, &s, NULL);
400 if (asprintf(&t, UID_FMT, uid) < 0)
403 FOREACH_WORD(word, l, s, state)
404 if (strneq(t, word, l))
410 static int uid_get_array(uid_t uid, const char *variable, char ***array) {
411 _cleanup_free_ char *p = NULL, *s = NULL;
417 r = file_of_uid(uid, &p);
421 r = parse_env_file(NULL, p, NEWLINE, variable, &s, NULL);
422 if (r == -ENOENT || (r >= 0 && isempty(s))) {
430 a = strv_split(s, " ");
435 r = (int) strv_length(a);
445 _public_ int sd_uid_get_sessions(uid_t uid, int require_active, char ***sessions) {
446 return uid_get_array(
448 require_active == 0 ? "ONLINE_SESSIONS" :
449 require_active > 0 ? "ACTIVE_SESSIONS" :
454 _public_ int sd_uid_get_seats(uid_t uid, int require_active, char ***seats) {
455 return uid_get_array(
457 require_active == 0 ? "ONLINE_SEATS" :
458 require_active > 0 ? "ACTIVE_SEATS" :
463 static int file_of_session(const char *session, char **_p) {
470 if (!session_id_valid(session))
473 p = strappend("/run/systemd/sessions/", session);
475 _cleanup_free_ char *buf = NULL;
477 r = sd_pid_get_session(0, &buf);
481 p = strappend("/run/systemd/sessions/", buf);
491 _public_ int sd_session_is_active(const char *session) {
492 _cleanup_free_ char *p = NULL, *s = NULL;
495 r = file_of_session(session, &p);
499 r = parse_env_file(NULL, p, NEWLINE, "ACTIVE", &s, NULL);
507 return parse_boolean(s);
510 _public_ int sd_session_is_remote(const char *session) {
511 _cleanup_free_ char *p = NULL, *s = NULL;
514 r = file_of_session(session, &p);
518 r = parse_env_file(NULL, p, NEWLINE, "REMOTE", &s, NULL);
526 return parse_boolean(s);
529 _public_ int sd_session_get_state(const char *session, char **state) {
530 _cleanup_free_ char *p = NULL, *s = NULL;
533 assert_return(state, -EINVAL);
535 r = file_of_session(session, &p);
539 r = parse_env_file(NULL, p, NEWLINE, "STATE", &s, NULL);
547 *state = TAKE_PTR(s);
552 _public_ int sd_session_get_uid(const char *session, uid_t *uid) {
554 _cleanup_free_ char *p = NULL, *s = NULL;
556 assert_return(uid, -EINVAL);
558 r = file_of_session(session, &p);
562 r = parse_env_file(NULL, p, NEWLINE, "UID", &s, NULL);
570 return parse_uid(s, uid);
573 static int session_get_string(const char *session, const char *field, char **value) {
574 _cleanup_free_ char *p = NULL, *s = NULL;
577 assert_return(value, -EINVAL);
580 r = file_of_session(session, &p);
584 r = parse_env_file(NULL, p, NEWLINE, field, &s, NULL);
592 *value = TAKE_PTR(s);
596 _public_ int sd_session_get_seat(const char *session, char **seat) {
597 return session_get_string(session, "SEAT", seat);
600 _public_ int sd_session_get_tty(const char *session, char **tty) {
601 return session_get_string(session, "TTY", tty);
604 _public_ int sd_session_get_vt(const char *session, unsigned *vtnr) {
605 _cleanup_free_ char *vtnr_string = NULL;
609 assert_return(vtnr, -EINVAL);
611 r = session_get_string(session, "VTNR", &vtnr_string);
615 r = safe_atou(vtnr_string, &u);
623 _public_ int sd_session_get_service(const char *session, char **service) {
624 return session_get_string(session, "SERVICE", service);
627 _public_ int sd_session_get_type(const char *session, char **type) {
628 return session_get_string(session, "TYPE", type);
631 _public_ int sd_session_get_class(const char *session, char **class) {
632 return session_get_string(session, "CLASS", class);
635 _public_ int sd_session_get_desktop(const char *session, char **desktop) {
636 _cleanup_free_ char *escaped = NULL;
640 assert_return(desktop, -EINVAL);
642 r = session_get_string(session, "DESKTOP", &escaped);
646 r = cunescape(escaped, 0, &t);
654 _public_ int sd_session_get_display(const char *session, char **display) {
655 return session_get_string(session, "DISPLAY", display);
658 _public_ int sd_session_get_remote_user(const char *session, char **remote_user) {
659 return session_get_string(session, "REMOTE_USER", remote_user);
662 _public_ int sd_session_get_remote_host(const char *session, char **remote_host) {
663 return session_get_string(session, "REMOTE_HOST", remote_host);
666 _public_ int sd_seat_get_active(const char *seat, char **session, uid_t *uid) {
667 _cleanup_free_ char *p = NULL, *s = NULL, *t = NULL;
670 assert_return(session || uid, -EINVAL);
672 r = file_of_seat(seat, &p);
676 r = parse_env_file(NULL, p, NEWLINE,
692 r = parse_uid(t, uid);
698 *session = TAKE_PTR(s);
703 _public_ int sd_seat_get_sessions(const char *seat, char ***sessions, uid_t **uids, unsigned *n_uids) {
704 _cleanup_free_ char *p = NULL, *s = NULL, *t = NULL;
705 _cleanup_strv_free_ char **a = NULL;
706 _cleanup_free_ uid_t *b = NULL;
710 r = file_of_seat(seat, &p);
714 r = parse_env_file(NULL, p, NEWLINE,
724 a = strv_split(s, " ");
730 const char *word, *state;
733 FOREACH_WORD(word, l, t, state)
743 FOREACH_WORD(word, l, t, state) {
744 _cleanup_free_ char *k = NULL;
746 k = strndup(word, l);
750 r = parse_uid(k, b + i);
759 r = (int) strv_length(a);
762 *sessions = TAKE_PTR(a);
773 static int seat_get_can(const char *seat, const char *variable) {
774 _cleanup_free_ char *p = NULL, *s = NULL;
779 r = file_of_seat(seat, &p);
783 r = parse_env_file(NULL, p, NEWLINE,
793 return parse_boolean(s);
796 _public_ int sd_seat_can_multi_session(const char *seat) {
797 return seat_get_can(seat, "CAN_MULTI_SESSION");
800 _public_ int sd_seat_can_tty(const char *seat) {
801 return seat_get_can(seat, "CAN_TTY");
804 _public_ int sd_seat_can_graphical(const char *seat) {
805 return seat_get_can(seat, "CAN_GRAPHICAL");
808 _public_ int sd_get_seats(char ***seats) {
811 r = get_files_in_directory("/run/systemd/seats/", seats);
820 _public_ int sd_get_sessions(char ***sessions) {
823 r = get_files_in_directory("/run/systemd/sessions/", sessions);
832 _public_ int sd_get_uids(uid_t **users) {
833 _cleanup_closedir_ DIR *d;
837 _cleanup_free_ uid_t *l = NULL;
839 d = opendir("/run/systemd/users/");
841 if (errno == ENOENT) {
849 FOREACH_DIRENT_ALL(de, d, return -errno) {
853 dirent_ensure_type(d, de);
855 if (!dirent_is_file(de))
858 k = parse_uid(de->d_name, &uid);
863 if ((unsigned) r >= n) {
867 t = realloc(l, sizeof(uid_t) * n);
874 assert((unsigned) r < n);
881 *users = TAKE_PTR(l);
886 _public_ int sd_get_machine_names(char ***machines) {
887 _cleanup_strv_free_ char **l = NULL;
891 r = get_files_in_directory("/run/systemd/machines/", &l);
903 /* Filter out the unit: symlinks */
904 for (a = b = l; *a; a++) {
905 if (startswith(*a, "unit:") || !machine_name_is_valid(*a))
918 *machines = TAKE_PTR(l);
923 _public_ int sd_machine_get_class(const char *machine, char **class) {
924 _cleanup_free_ char *c = NULL;
928 assert_return(machine_name_is_valid(machine), -EINVAL);
929 assert_return(class, -EINVAL);
931 p = strjoina("/run/systemd/machines/", machine);
932 r = parse_env_file(NULL, p, NEWLINE, "CLASS", &c, NULL);
940 *class = TAKE_PTR(c);
945 _public_ int sd_machine_get_ifindices(const char *machine, int **ifindices) {
946 _cleanup_free_ char *netif = NULL;
947 size_t l, allocated = 0, nr = 0;
949 const char *p, *word, *state;
952 assert_return(machine_name_is_valid(machine), -EINVAL);
953 assert_return(ifindices, -EINVAL);
955 p = strjoina("/run/systemd/machines/", machine);
956 r = parse_env_file(NULL, p, NEWLINE, "NETIF", &netif, NULL);
966 FOREACH_WORD(word, l, netif, state) {
970 *(char*) (mempcpy(buf, word, l)) = 0;
972 if (parse_ifindex(buf, &ifi) < 0)
975 if (!GREEDY_REALLOC(ni, allocated, nr+1)) {
987 static inline int MONITOR_TO_FD(sd_login_monitor *m) {
988 return (int) (unsigned long) m - 1;
991 static inline sd_login_monitor* FD_TO_MONITOR(int fd) {
992 return (sd_login_monitor*) (unsigned long) (fd + 1);
995 _public_ int sd_login_monitor_new(const char *category, sd_login_monitor **m) {
996 _cleanup_close_ int fd = -1;
1000 assert_return(m, -EINVAL);
1002 fd = inotify_init1(IN_NONBLOCK|IN_CLOEXEC);
1006 if (!category || streq(category, "seat")) {
1007 k = inotify_add_watch(fd, "/run/systemd/seats/", IN_MOVED_TO|IN_DELETE);
1014 if (!category || streq(category, "session")) {
1015 k = inotify_add_watch(fd, "/run/systemd/sessions/", IN_MOVED_TO|IN_DELETE);
1022 if (!category || streq(category, "uid")) {
1023 k = inotify_add_watch(fd, "/run/systemd/users/", IN_MOVED_TO|IN_DELETE);
1030 if (!category || streq(category, "machine")) {
1031 k = inotify_add_watch(fd, "/run/systemd/machines/", IN_MOVED_TO|IN_DELETE);
1041 *m = FD_TO_MONITOR(fd);
1047 _public_ sd_login_monitor* sd_login_monitor_unref(sd_login_monitor *m) {
1053 fd = MONITOR_TO_FD(m);
1059 _public_ int sd_login_monitor_flush(sd_login_monitor *m) {
1062 assert_return(m, -EINVAL);
1064 r = flush_fd(MONITOR_TO_FD(m));
1071 _public_ int sd_login_monitor_get_fd(sd_login_monitor *m) {
1073 assert_return(m, -EINVAL);
1075 return MONITOR_TO_FD(m);
1078 _public_ int sd_login_monitor_get_events(sd_login_monitor *m) {
1080 assert_return(m, -EINVAL);
1082 /* For now we will only return POLLIN here, since we don't
1083 * need anything else ever for inotify. However, let's have
1084 * this API to keep our options open should we later on need
1089 _public_ int sd_login_monitor_get_timeout(sd_login_monitor *m, uint64_t *timeout_usec) {
1091 assert_return(m, -EINVAL);
1092 assert_return(timeout_usec, -EINVAL);
1094 /* For now we will only return (uint64_t) -1, since we don't
1095 * need any timeout. However, let's have this API to keep our
1096 * options open should we later on need it. */
1097 *timeout_usec = (uint64_t) -1;