src/systemd/sd-login.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 #ifndef foosdloginhfoo
   3 #define foosdloginhfoo
   4
   5 /***
   6   systemd is free software; you can redistribute it and/or modify it
   7   under the terms of the GNU Lesser General Public License as published by
   8   the Free Software Foundation; either version 2.1 of the License, or
   9   (at your option) any later version.
  10
  11   systemd is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   Lesser General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  18 ***/
  19
  20 #include <inttypes.h>
  21 #include <sys/types.h>
  22
  23 #include "_sd-common.h"
  24
  25 /*
  26  * A few points:
  27  *
  28  * Instead of returning an empty string array or empty uid array, we
  29  * may return NULL.
  30  *
  31  * Free the data the library returns with libc free(). String arrays
  32  * are NULL terminated, and you need to free the array itself, in
  33  * addition to the strings contained.
  34  *
  35  * We return error codes as negative errno, kernel-style. On success, we
  36  * return 0 or positive.
  37  *
  38  * These functions access data in /proc, /sys/fs/cgroup, and /run. All
  39  * of these are virtual file systems; therefore, accesses are
  40  * relatively cheap.
  41  *
  42  * See sd-login(3) for more information.
  43  */
  44
  45 _SD_BEGIN_DECLARATIONS;
  46
  47 /* Get session from PID. Note that 'shared' processes of a user are
  48  * not attached to a session, but only attached to a user. This will
  49  * return an error for system processes and 'shared' processes of a
  50  * user. */
  51 int sd_pid_get_session(pid_t pid, char **session);
  52
  53 /* Get UID of the owner of the session of the PID (or in case the
  54  * process is a 'shared' user process, the UID of that user is
  55  * returned). This will not return the UID of the process, but rather
  56  * the UID of the owner of the cgroup that the process is in. This will
  57  * return an error for system processes. */
  58 int sd_pid_get_owner_uid(pid_t pid, uid_t *uid);
  59
  60 /* Get systemd non-slice unit (i.e. service) name from PID, for system
  61  * services. This will return an error for non-service processes. */
  62 int sd_pid_get_unit(pid_t pid, char **unit);
  63
  64 /* Get systemd non-slice unit (i.e. service) name from PID, for user
  65  * services. This will return an error for non-user-service
  66  * processes. */
  67 int sd_pid_get_user_unit(pid_t pid, char **unit);
  68
  69 /* Get slice name from PID. */
  70 int sd_pid_get_slice(pid_t pid, char **slice);
  71
  72 /* Get user slice name from PID. */
  73 int sd_pid_get_user_slice(pid_t pid, char **slice);
  74
  75 /* Get machine name from PID, for processes assigned to a VM or
  76  * container. This will return an error for non-machine processes. */
  77 int sd_pid_get_machine_name(pid_t pid, char **machine);
  78
  79 /* Get the control group from a PID, relative to the root of the
  80  * hierarchy. */
  81 int sd_pid_get_cgroup(pid_t pid, char **cgroup);
  82
  83 /* Similar to sd_pid_get_session(), but retrieves data about the peer
  84  * of a connected AF_UNIX socket */
  85 int sd_peer_get_session(int fd, char **session);
  86
  87 /* Similar to sd_pid_get_owner_uid(), but retrieves data about the peer of
  88  * a connected AF_UNIX socket */
  89 int sd_peer_get_owner_uid(int fd, uid_t *uid);
  90
  91 /* Similar to sd_pid_get_unit(), but retrieves data about the peer of
  92  * a connected AF_UNIX socket */
  93 int sd_peer_get_unit(int fd, char **unit);
  94
  95 /* Similar to sd_pid_get_user_unit(), but retrieves data about the peer of
  96  * a connected AF_UNIX socket */
  97 int sd_peer_get_user_unit(int fd, char **unit);
  98
  99 /* Similar to sd_pid_get_slice(), but retrieves data about the peer of
 100  * a connected AF_UNIX socket */
 101 int sd_peer_get_slice(int fd, char **slice);
 102
 103 /* Similar to sd_pid_get_user_slice(), but retrieves data about the peer of
 104  * a connected AF_UNIX socket */
 105 int sd_peer_get_user_slice(int fd, char **slice);
 106
 107 /* Similar to sd_pid_get_machine_name(), but retrieves data about the
 108  * peer of a connected AF_UNIX socket */
 109 int sd_peer_get_machine_name(int fd, char **machine);
 110
 111 /* Similar to sd_pid_get_cgroup(), but retrieves data about the peer
 112  * of a connected AF_UNIX socket. */
 113 int sd_peer_get_cgroup(pid_t pid, char **cgroup);
 114
 115 /* Get state from UID. Possible states: offline, lingering, online, active, closing */
 116 int sd_uid_get_state(uid_t uid, char **state);
 117
 118 /* Return primary session of user, if there is any */
 119 int sd_uid_get_display(uid_t uid, char **session);
 120
 121 /* Return 1 if UID has session on seat. If require_active is true, this will
 122  * look for active sessions only. */
 123 int sd_uid_is_on_seat(uid_t uid, int require_active, const char *seat);
 124
 125 /* Return sessions of user. If require_active is true, this will look for
 126  * active sessions only. Returns the number of sessions.
 127  * If sessions is NULL, this will just return the number of sessions. */
 128 int sd_uid_get_sessions(uid_t uid, int require_active, char ***sessions);
 129
 130 /* Return seats of user is on. If require_active is true, this will look for
 131  * active seats only. Returns the number of seats.
 132  * If seats is NULL, this will just return the number of seats. */
 133 int sd_uid_get_seats(uid_t uid, int require_active, char ***seats);
 134
 135 /* Return 1 if the session is active. */
 136 int sd_session_is_active(const char *session);
 137
 138 /* Return 1 if the session is remote. */
 139 int sd_session_is_remote(const char *session);
 140
 141 /* Get state from session. Possible states: online, active, closing.
 142  * This function is a more generic version of sd_session_is_active(). */
 143 int sd_session_get_state(const char *session, char **state);
 144
 145 /* Determine user ID of session */
 146 int sd_session_get_uid(const char *session, uid_t *uid);
 147
 148 /* Determine seat of session */
 149 int sd_session_get_seat(const char *session, char **seat);
 150
 151 /* Determine the (PAM) service name this session was registered by. */
 152 int sd_session_get_service(const char *session, char **service);
 153
 154 /* Determine the type of this session, i.e. one of "tty", "x11", "wayland", "mir" or "unspecified". */
 155 int sd_session_get_type(const char *session, char **type);
 156
 157 /* Determine the class of this session, i.e. one of "user", "greeter" or "lock-screen". */
 158 int sd_session_get_class(const char *session, char **clazz);
 159
 160 /* Determine the desktop brand of this session, i.e. something like "GNOME", "KDE" or "systemd-console". */
 161 int sd_session_get_desktop(const char *session, char **desktop);
 162
 163 /* Determine the X11 display of this session. */
 164 int sd_session_get_display(const char *session, char **display);
 165
 166 /* Determine the remote host of this session. */
 167 int sd_session_get_remote_host(const char *session, char **remote_host);
 168
 169 /* Determine the remote user of this session (if provided by PAM). */
 170 int sd_session_get_remote_user(const char *session, char **remote_user);
 171
 172 /* Determine the TTY of this session. */
 173 int sd_session_get_tty(const char *session, char **display);
 174
 175 /* Determine the VT number of this session. */
 176 int sd_session_get_vt(const char *session, unsigned *vtnr);
 177
 178 /* Return active session and user of seat */
 179 int sd_seat_get_active(const char *seat, char **session, uid_t *uid);
 180
 181 /* Return sessions and users on seat. Returns number of sessions.
 182  * If sessions is NULL, this returns only the number of sessions. */
 183 int sd_seat_get_sessions(const char *seat, char ***sessions, uid_t **uid, unsigned *n_uids);
 184
 185 /* Return whether the seat is multi-session capable */
 186 int sd_seat_can_multi_session(const char *seat);
 187
 188 /* Return whether the seat is TTY capable, i.e. suitable for showing console UIs */
 189 int sd_seat_can_tty(const char *seat);
 190
 191 /* Return whether the seat is graphics capable, i.e. suitable for showing graphical UIs */
 192 int sd_seat_can_graphical(const char *seat);
 193
 194 /* Return the class of machine */
 195 int sd_machine_get_class(const char *machine, char **clazz);
 196
 197 /* Return the list if host-side network interface indices of a machine */
 198 int sd_machine_get_ifindices(const char *machine, int **ifindices);
 199
 200 /* Get all seats, store in *seats. Returns the number of seats. If
 201  * seats is NULL, this only returns the number of seats. */
 202 int sd_get_seats(char ***seats);
 203
 204 /* Get all sessions, store in *sessions. Returns the number of
 205  * sessions. If sessions is NULL, this only returns the number of sessions. */
 206 int sd_get_sessions(char ***sessions);
 207
 208 /* Get all logged in users, store in *users. Returns the number of
 209  * users. If users is NULL, this only returns the number of users. */
 210 int sd_get_uids(uid_t **users);
 211
 212 /* Get all running virtual machines/containers */
 213 int sd_get_machine_names(char ***machines);
 214
 215 /* Monitor object */
 216 typedef struct sd_login_monitor sd_login_monitor;
 217
 218 /* Create a new monitor. Category must be NULL, "seat", "session",
 219  * "uid", or "machine" to get monitor events for the specific category
 220  * (or all). */
 221 int sd_login_monitor_new(const char *category, sd_login_monitor** ret);
 222
 223 /* Destroys the passed monitor. Returns NULL. */
 224 sd_login_monitor* sd_login_monitor_unref(sd_login_monitor *m);
 225
 226 /* Flushes the monitor */
 227 int sd_login_monitor_flush(sd_login_monitor *m);
 228
 229 /* Get FD from monitor */
 230 int sd_login_monitor_get_fd(sd_login_monitor *m);
 231
 232 /* Get poll() mask to monitor */
 233 int sd_login_monitor_get_events(sd_login_monitor *m);
 234
 235 /* Get timeout for poll(), as usec value relative to CLOCK_MONOTONIC's epoch */
 236 int sd_login_monitor_get_timeout(sd_login_monitor *m, uint64_t *timeout_usec);
 237
 238 _SD_DEFINE_POINTER_CLEANUP_FUNC(sd_login_monitor, sd_login_monitor_unref);
 239
 240 _SD_END_DECLARATIONS;
 241
 242 #endif