src/login/logind-seat-dbus.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 /***
   3   This file is part of systemd.
   4
   5   Copyright 2011 Lennart Poettering
   6 ***/
   7
   8 #include <errno.h>
   9 #include <string.h>
  10
  11 #include "alloc-util.h"
  12 #include "bus-common-errors.h"
  13 #include "bus-label.h"
  14 #include "bus-util.h"
  15 #include "logind-seat.h"
  16 #include "logind.h"
  17 #include "strv.h"
  18 #include "user-util.h"
  19 #include "util.h"
  20
  21 static BUS_DEFINE_PROPERTY_GET(property_get_can_multi_session, "b", Seat, seat_can_multi_session);
  22 static BUS_DEFINE_PROPERTY_GET(property_get_can_tty, "b", Seat, seat_can_tty);
  23 static BUS_DEFINE_PROPERTY_GET(property_get_can_graphical, "b", Seat, seat_can_graphical);
  24
  25 static int property_get_active_session(
  26                 sd_bus *bus,
  27                 const char *path,
  28                 const char *interface,
  29                 const char *property,
  30                 sd_bus_message *reply,
  31                 void *userdata,
  32                 sd_bus_error *error) {
  33
  34         _cleanup_free_ char *p = NULL;
  35         Seat *s = userdata;
  36
  37         assert(bus);
  38         assert(reply);
  39         assert(s);
  40
  41         p = s->active ? session_bus_path(s->active) : strdup("/");
  42         if (!p)
  43                 return -ENOMEM;
  44
  45         return sd_bus_message_append(reply, "(so)", s->active ? s->active->id : "", p);
  46 }
  47
  48 static int property_get_sessions(
  49                 sd_bus *bus,
  50                 const char *path,
  51                 const char *interface,
  52                 const char *property,
  53                 sd_bus_message *reply,
  54                 void *userdata,
  55                 sd_bus_error *error) {
  56
  57         Seat *s = userdata;
  58         Session *session;
  59         int r;
  60
  61         assert(bus);
  62         assert(reply);
  63         assert(s);
  64
  65         r = sd_bus_message_open_container(reply, 'a', "(so)");
  66         if (r < 0)
  67                 return r;
  68
  69         LIST_FOREACH(sessions_by_seat, session, s->sessions) {
  70                 _cleanup_free_ char *p = NULL;
  71
  72                 p = session_bus_path(session);
  73                 if (!p)
  74                         return -ENOMEM;
  75
  76                 r = sd_bus_message_append(reply, "(so)", session->id, p);
  77                 if (r < 0)
  78                         return r;
  79
  80         }
  81
  82         r = sd_bus_message_close_container(reply);
  83         if (r < 0)
  84                 return r;
  85
  86         return 1;
  87 }
  88
  89 static int property_get_idle_hint(
  90                 sd_bus *bus,
  91                 const char *path,
  92                 const char *interface,
  93                 const char *property,
  94                 sd_bus_message *reply,
  95                 void *userdata,
  96                 sd_bus_error *error) {
  97
  98         Seat *s = userdata;
  99
 100         assert(bus);
 101         assert(reply);
 102         assert(s);
 103
 104         return sd_bus_message_append(reply, "b", seat_get_idle_hint(s, NULL) > 0);
 105 }
 106
 107 static int property_get_idle_since_hint(
 108                 sd_bus *bus,
 109                 const char *path,
 110                 const char *interface,
 111                 const char *property,
 112                 sd_bus_message *reply,
 113                 void *userdata,
 114                 sd_bus_error *error) {
 115
 116         Seat *s = userdata;
 117         dual_timestamp t;
 118         uint64_t u;
 119         int r;
 120
 121         assert(bus);
 122         assert(reply);
 123         assert(s);
 124
 125         r = seat_get_idle_hint(s, &t);
 126         if (r < 0)
 127                 return r;
 128
 129         u = streq(property, "IdleSinceHint") ? t.realtime : t.monotonic;
 130
 131         return sd_bus_message_append(reply, "t", u);
 132 }
 133
 134 int bus_seat_method_terminate(sd_bus_message *message, void *userdata, sd_bus_error *error) {
 135         Seat *s = userdata;
 136         int r;
 137
 138         assert(message);
 139         assert(s);
 140
 141         r = bus_verify_polkit_async(
 142                         message,
 143                         CAP_KILL,
 144                         "org.freedesktop.login1.manage",
 145                         NULL,
 146                         false,
 147                         UID_INVALID,
 148                         &s->manager->polkit_registry,
 149                         error);
 150         if (r < 0)
 151                 return r;
 152         if (r == 0)
 153                 return 1; /* Will call us back */
 154
 155         r = seat_stop_sessions(s, true);
 156         if (r < 0)
 157                 return r;
 158
 159         return sd_bus_reply_method_return(message, NULL);
 160 }
 161
 162 static int method_activate_session(sd_bus_message *message, void *userdata, sd_bus_error *error) {
 163         Seat *s = userdata;
 164         const char *name;
 165         Session *session;
 166         int r;
 167
 168         assert(message);
 169         assert(s);
 170
 171         r = sd_bus_message_read(message, "s", &name);
 172         if (r < 0)
 173                 return r;
 174
 175         session = hashmap_get(s->manager->sessions, name);
 176         if (!session)
 177                 return sd_bus_error_setf(error, BUS_ERROR_NO_SUCH_SESSION, "No session '%s' known", name);
 178
 179         if (session->seat != s)
 180                 return sd_bus_error_setf(error, BUS_ERROR_SESSION_NOT_ON_SEAT, "Session %s not on seat %s", name, s->id);
 181
 182         r = session_activate(session);
 183         if (r < 0)
 184                 return r;
 185
 186         return sd_bus_reply_method_return(message, NULL);
 187 }
 188
 189 static int method_switch_to(sd_bus_message *message, void *userdata, sd_bus_error *error) {
 190         Seat *s = userdata;
 191         unsigned int to;
 192         int r;
 193
 194         assert(message);
 195         assert(s);
 196
 197         r = sd_bus_message_read(message, "u", &to);
 198         if (r < 0)
 199                 return r;
 200
 201         if (to <= 0)
 202                 return -EINVAL;
 203
 204         r = seat_switch_to(s, to);
 205         if (r < 0)
 206                 return r;
 207
 208         return sd_bus_reply_method_return(message, NULL);
 209 }
 210
 211 static int method_switch_to_next(sd_bus_message *message, void *userdata, sd_bus_error *error) {
 212         Seat *s = userdata;
 213         int r;
 214
 215         assert(message);
 216         assert(s);
 217
 218         r = seat_switch_to_next(s);
 219         if (r < 0)
 220                 return r;
 221
 222         return sd_bus_reply_method_return(message, NULL);
 223 }
 224
 225 static int method_switch_to_previous(sd_bus_message *message, void *userdata, sd_bus_error *error) {
 226         Seat *s = userdata;
 227         int r;
 228
 229         assert(message);
 230         assert(s);
 231
 232         r = seat_switch_to_previous(s);
 233         if (r < 0)
 234                 return r;
 235
 236         return sd_bus_reply_method_return(message, NULL);
 237 }
 238
 239 const sd_bus_vtable seat_vtable[] = {
 240         SD_BUS_VTABLE_START(0),
 241
 242         SD_BUS_PROPERTY("Id", "s", NULL, offsetof(Seat, id), SD_BUS_VTABLE_PROPERTY_CONST),
 243         SD_BUS_PROPERTY("ActiveSession", "(so)", property_get_active_session, 0, SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
 244         SD_BUS_PROPERTY("CanMultiSession", "b", property_get_can_multi_session, 0, SD_BUS_VTABLE_PROPERTY_CONST),
 245         SD_BUS_PROPERTY("CanTTY", "b", property_get_can_tty, 0, SD_BUS_VTABLE_PROPERTY_CONST),
 246         SD_BUS_PROPERTY("CanGraphical", "b", property_get_can_graphical, 0, SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
 247         SD_BUS_PROPERTY("Sessions", "a(so)", property_get_sessions, 0, 0),
 248         SD_BUS_PROPERTY("IdleHint", "b", property_get_idle_hint, 0, SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
 249         SD_BUS_PROPERTY("IdleSinceHint", "t", property_get_idle_since_hint, 0, SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
 250         SD_BUS_PROPERTY("IdleSinceHintMonotonic", "t", property_get_idle_since_hint, 0, SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
 251
 252         SD_BUS_METHOD("Terminate", NULL, NULL, bus_seat_method_terminate, SD_BUS_VTABLE_UNPRIVILEGED),
 253         SD_BUS_METHOD("ActivateSession", "s", NULL, method_activate_session, SD_BUS_VTABLE_UNPRIVILEGED),
 254         SD_BUS_METHOD("SwitchTo", "u", NULL, method_switch_to, SD_BUS_VTABLE_UNPRIVILEGED),
 255         SD_BUS_METHOD("SwitchToNext", NULL, NULL, method_switch_to_next, SD_BUS_VTABLE_UNPRIVILEGED),
 256         SD_BUS_METHOD("SwitchToPrevious", NULL, NULL, method_switch_to_previous, SD_BUS_VTABLE_UNPRIVILEGED),
 257
 258         SD_BUS_VTABLE_END
 259 };
 260
 261 int seat_object_find(sd_bus *bus, const char *path, const char *interface, void *userdata, void **found, sd_bus_error *error) {
 262         Manager *m = userdata;
 263         Seat *seat;
 264         int r;
 265
 266         assert(bus);
 267         assert(path);
 268         assert(interface);
 269         assert(found);
 270         assert(m);
 271
 272         if (streq(path, "/org/freedesktop/login1/seat/self")) {
 273                 sd_bus_message *message;
 274
 275                 message = sd_bus_get_current_message(bus);
 276                 if (!message)
 277                         return 0;
 278
 279                 r = manager_get_seat_from_creds(m, message, NULL, error, &seat);
 280                 if (r < 0)
 281                         return r;
 282         } else {
 283                 _cleanup_free_ char *e = NULL;
 284                 const char *p;
 285
 286                 p = startswith(path, "/org/freedesktop/login1/seat/");
 287                 if (!p)
 288                         return 0;
 289
 290                 e = bus_label_unescape(p);
 291                 if (!e)
 292                         return -ENOMEM;
 293
 294                 seat = hashmap_get(m->seats, e);
 295                 if (!seat)
 296                         return 0;
 297         }
 298
 299         *found = seat;
 300         return 1;
 301 }
 302
 303 char *seat_bus_path(Seat *s) {
 304         _cleanup_free_ char *t = NULL;
 305
 306         assert(s);
 307
 308         t = bus_label_escape(s->id);
 309         if (!t)
 310                 return NULL;
 311
 312         return strappend("/org/freedesktop/login1/seat/", t);
 313 }
 314
 315 int seat_node_enumerator(sd_bus *bus, const char *path, void *userdata, char ***nodes, sd_bus_error *error) {
 316         _cleanup_strv_free_ char **l = NULL;
 317         sd_bus_message *message;
 318         Manager *m = userdata;
 319         Seat *seat;
 320         Iterator i;
 321         int r;
 322
 323         assert(bus);
 324         assert(path);
 325         assert(nodes);
 326
 327         HASHMAP_FOREACH(seat, m->seats, i) {
 328                 char *p;
 329
 330                 p = seat_bus_path(seat);
 331                 if (!p)
 332                         return -ENOMEM;
 333
 334                 r = strv_consume(&l, p);
 335                 if (r < 0)
 336                         return r;
 337         }
 338
 339         message = sd_bus_get_current_message(bus);
 340         if (message) {
 341                 _cleanup_(sd_bus_creds_unrefp) sd_bus_creds *creds = NULL;
 342                 const char *name;
 343                 Session *session;
 344
 345                 r = sd_bus_query_sender_creds(message, SD_BUS_CREDS_SESSION|SD_BUS_CREDS_AUGMENT, &creds);
 346                 if (r >= 0) {
 347                         r = sd_bus_creds_get_session(creds, &name);
 348                         if (r >= 0) {
 349                                 session = hashmap_get(m->sessions, name);
 350                                 if (session && session->seat) {
 351                                         r = strv_extend(&l, "/org/freedesktop/login1/seat/self");
 352                                         if (r < 0)
 353                                                 return r;
 354                                 }
 355                         }
 356                 }
 357         }
 358
 359         *nodes = TAKE_PTR(l);
 360
 361         return 1;
 362 }
 363
 364 int seat_send_signal(Seat *s, bool new_seat) {
 365         _cleanup_free_ char *p = NULL;
 366
 367         assert(s);
 368
 369         p = seat_bus_path(s);
 370         if (!p)
 371                 return -ENOMEM;
 372
 373         return sd_bus_emit_signal(
 374                         s->manager->bus,
 375                         "/org/freedesktop/login1",
 376                         "org.freedesktop.login1.Manager",
 377                         new_seat ? "SeatNew" : "SeatRemoved",
 378                         "so", s->id, p);
 379 }
 380
 381 int seat_send_changed(Seat *s, const char *properties, ...) {
 382         _cleanup_free_ char *p = NULL;
 383         char **l;
 384
 385         assert(s);
 386
 387         if (!s->started)
 388                 return 0;
 389
 390         p = seat_bus_path(s);
 391         if (!p)
 392                 return -ENOMEM;
 393
 394         l = strv_from_stdarg_alloca(properties);
 395
 396         return sd_bus_emit_properties_changed_strv(s->manager->bus, p, "org.freedesktop.login1.Seat", l);
 397 }