src/login/logind-seat-dbus.c

   1 /***
   2   This file is part of systemd.
   3
   4   Copyright 2011 Lennart Poettering
   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 <errno.h>
  21 #include <string.h>
  22
  23 #include "alloc-util.h"
  24 #include "bus-common-errors.h"
  25 #include "bus-label.h"
  26 #include "bus-util.h"
  27 #include "logind-seat.h"
  28 #include "logind.h"
  29 #include "strv.h"
  30 #include "user-util.h"
  31 #include "util.h"
  32
  33 static int property_get_active_session(
  34                 sd_bus *bus,
  35                 const char *path,
  36                 const char *interface,
  37                 const char *property,
  38                 sd_bus_message *reply,
  39                 void *userdata,
  40                 sd_bus_error *error) {
  41
  42         _cleanup_free_ char *p = NULL;
  43         Seat *s = userdata;
  44
  45         assert(bus);
  46         assert(reply);
  47         assert(s);
  48
  49         p = s->active ? session_bus_path(s->active) : strdup("/");
  50         if (!p)
  51                 return -ENOMEM;
  52
  53         return sd_bus_message_append(reply, "(so)", s->active ? s->active->id : "", p);
  54 }
  55
  56 static int property_get_can_multi_session(
  57                 sd_bus *bus,
  58                 const char *path,
  59                 const char *interface,
  60                 const char *property,
  61                 sd_bus_message *reply,
  62                 void *userdata,
  63                 sd_bus_error *error) {
  64
  65         Seat *s = userdata;
  66
  67         assert(bus);
  68         assert(reply);
  69         assert(s);
  70
  71         return sd_bus_message_append(reply, "b", seat_can_multi_session(s));
  72 }
  73
  74 static int property_get_can_tty(
  75                 sd_bus *bus,
  76                 const char *path,
  77                 const char *interface,
  78                 const char *property,
  79                 sd_bus_message *reply,
  80                 void *userdata,
  81                 sd_bus_error *error) {
  82
  83         Seat *s = userdata;
  84
  85         assert(bus);
  86         assert(reply);
  87         assert(s);
  88
  89         return sd_bus_message_append(reply, "b", seat_can_tty(s));
  90 }
  91
  92 static int property_get_can_graphical(
  93                 sd_bus *bus,
  94                 const char *path,
  95                 const char *interface,
  96                 const char *property,
  97                 sd_bus_message *reply,
  98                 void *userdata,
  99                 sd_bus_error *error) {
 100
 101         Seat *s = userdata;
 102
 103         assert(bus);
 104         assert(reply);
 105         assert(s);
 106
 107         return sd_bus_message_append(reply, "b", seat_can_graphical(s));
 108 }
 109
 110 static int property_get_sessions(
 111                 sd_bus *bus,
 112                 const char *path,
 113                 const char *interface,
 114                 const char *property,
 115                 sd_bus_message *reply,
 116                 void *userdata,
 117                 sd_bus_error *error) {
 118
 119         Seat *s = userdata;
 120         Session *session;
 121         int r;
 122
 123         assert(bus);
 124         assert(reply);
 125         assert(s);
 126
 127         r = sd_bus_message_open_container(reply, 'a', "(so)");
 128         if (r < 0)
 129                 return r;
 130
 131         LIST_FOREACH(sessions_by_seat, session, s->sessions) {
 132                 _cleanup_free_ char *p = NULL;
 133
 134                 p = session_bus_path(session);
 135                 if (!p)
 136                         return -ENOMEM;
 137
 138                 r = sd_bus_message_append(reply, "(so)", session->id, p);
 139                 if (r < 0)
 140                         return r;
 141
 142         }
 143
 144         r = sd_bus_message_close_container(reply);
 145         if (r < 0)
 146                 return r;
 147
 148         return 1;
 149 }
 150
 151 static int property_get_idle_hint(
 152                 sd_bus *bus,
 153                 const char *path,
 154                 const char *interface,
 155                 const char *property,
 156                 sd_bus_message *reply,
 157                 void *userdata,
 158                 sd_bus_error *error) {
 159
 160         Seat *s = userdata;
 161
 162         assert(bus);
 163         assert(reply);
 164         assert(s);
 165
 166         return sd_bus_message_append(reply, "b", seat_get_idle_hint(s, NULL) > 0);
 167 }
 168
 169 static int property_get_idle_since_hint(
 170                 sd_bus *bus,
 171                 const char *path,
 172                 const char *interface,
 173                 const char *property,
 174                 sd_bus_message *reply,
 175                 void *userdata,
 176                 sd_bus_error *error) {
 177
 178         Seat *s = userdata;
 179         dual_timestamp t;
 180         uint64_t u;
 181         int r;
 182
 183         assert(bus);
 184         assert(reply);
 185         assert(s);
 186
 187         r = seat_get_idle_hint(s, &t);
 188         if (r < 0)
 189                 return r;
 190
 191         u = streq(property, "IdleSinceHint") ? t.realtime : t.monotonic;
 192
 193         return sd_bus_message_append(reply, "t", u);
 194 }
 195
 196 int bus_seat_method_terminate(sd_bus_message *message, void *userdata, sd_bus_error *error) {
 197         Seat *s = userdata;
 198         int r;
 199
 200         assert(message);
 201         assert(s);
 202
 203         r = bus_verify_polkit_async(
 204                         message,
 205                         CAP_KILL,
 206                         "org.freedesktop.login1.manage",
 207                         NULL,
 208                         false,
 209                         UID_INVALID,
 210                         &s->manager->polkit_registry,
 211                         error);
 212         if (r < 0)
 213                 return r;
 214         if (r == 0)
 215                 return 1; /* Will call us back */
 216
 217         r = seat_stop_sessions(s, true);
 218         if (r < 0)
 219                 return r;
 220
 221         return sd_bus_reply_method_return(message, NULL);
 222 }
 223
 224 static int method_activate_session(sd_bus_message *message, void *userdata, sd_bus_error *error) {
 225         Seat *s = userdata;
 226         const char *name;
 227         Session *session;
 228         int r;
 229
 230         assert(message);
 231         assert(s);
 232
 233         r = sd_bus_message_read(message, "s", &name);
 234         if (r < 0)
 235                 return r;
 236
 237         session = hashmap_get(s->manager->sessions, name);
 238         if (!session)
 239                 return sd_bus_error_setf(error, BUS_ERROR_NO_SUCH_SESSION, "No session '%s' known", name);
 240
 241         if (session->seat != s)
 242                 return sd_bus_error_setf(error, BUS_ERROR_SESSION_NOT_ON_SEAT, "Session %s not on seat %s", name, s->id);
 243
 244         r = session_activate(session);
 245         if (r < 0)
 246                 return r;
 247
 248         return sd_bus_reply_method_return(message, NULL);
 249 }
 250
 251 static int method_switch_to(sd_bus_message *message, void *userdata, sd_bus_error *error) {
 252         Seat *s = userdata;
 253         unsigned int to;
 254         int r;
 255
 256         assert(message);
 257         assert(s);
 258
 259         r = sd_bus_message_read(message, "u", &to);
 260         if (r < 0)
 261                 return r;
 262
 263         if (to <= 0)
 264                 return -EINVAL;
 265
 266         r = seat_switch_to(s, to);
 267         if (r < 0)
 268                 return r;
 269
 270         return sd_bus_reply_method_return(message, NULL);
 271 }
 272
 273 static int method_switch_to_next(sd_bus_message *message, void *userdata, sd_bus_error *error) {
 274         Seat *s = userdata;
 275         int r;
 276
 277         assert(message);
 278         assert(s);
 279
 280         r = seat_switch_to_next(s);
 281         if (r < 0)
 282                 return r;
 283
 284         return sd_bus_reply_method_return(message, NULL);
 285 }
 286
 287 static int method_switch_to_previous(sd_bus_message *message, void *userdata, sd_bus_error *error) {
 288         Seat *s = userdata;
 289         int r;
 290
 291         assert(message);
 292         assert(s);
 293
 294         r = seat_switch_to_previous(s);
 295         if (r < 0)
 296                 return r;
 297
 298         return sd_bus_reply_method_return(message, NULL);
 299 }
 300
 301 const sd_bus_vtable seat_vtable[] = {
 302         SD_BUS_VTABLE_START(0),
 303
 304         SD_BUS_PROPERTY("Id", "s", NULL, offsetof(Seat, id), SD_BUS_VTABLE_PROPERTY_CONST),
 305         SD_BUS_PROPERTY("ActiveSession", "(so)", property_get_active_session, 0, SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
 306         SD_BUS_PROPERTY("CanMultiSession", "b", property_get_can_multi_session, 0, SD_BUS_VTABLE_PROPERTY_CONST),
 307         SD_BUS_PROPERTY("CanTTY", "b", property_get_can_tty, 0, SD_BUS_VTABLE_PROPERTY_CONST),
 308         SD_BUS_PROPERTY("CanGraphical", "b", property_get_can_graphical, 0, SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
 309         SD_BUS_PROPERTY("Sessions", "a(so)", property_get_sessions, 0, 0),
 310         SD_BUS_PROPERTY("IdleHint", "b", property_get_idle_hint, 0, SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
 311         SD_BUS_PROPERTY("IdleSinceHint", "t", property_get_idle_since_hint, 0, SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
 312         SD_BUS_PROPERTY("IdleSinceHintMonotonic", "t", property_get_idle_since_hint, 0, SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
 313
 314         SD_BUS_METHOD("Terminate", NULL, NULL, bus_seat_method_terminate, SD_BUS_VTABLE_UNPRIVILEGED),
 315         SD_BUS_METHOD("ActivateSession", "s", NULL, method_activate_session, SD_BUS_VTABLE_UNPRIVILEGED),
 316         SD_BUS_METHOD("SwitchTo", "u", NULL, method_switch_to, SD_BUS_VTABLE_UNPRIVILEGED),
 317         SD_BUS_METHOD("SwitchToNext", NULL, NULL, method_switch_to_next, SD_BUS_VTABLE_UNPRIVILEGED),
 318         SD_BUS_METHOD("SwitchToPrevious", NULL, NULL, method_switch_to_previous, SD_BUS_VTABLE_UNPRIVILEGED),
 319
 320         SD_BUS_VTABLE_END
 321 };
 322
 323 int seat_object_find(sd_bus *bus, const char *path, const char *interface, void *userdata, void **found, sd_bus_error *error) {
 324         Manager *m = userdata;
 325         Seat *seat;
 326         int r;
 327
 328         assert(bus);
 329         assert(path);
 330         assert(interface);
 331         assert(found);
 332         assert(m);
 333
 334         if (streq(path, "/org/freedesktop/login1/seat/self")) {
 335                 _cleanup_(sd_bus_creds_unrefp) sd_bus_creds *creds = NULL;
 336                 sd_bus_message *message;
 337                 Session *session;
 338                 const char *name;
 339
 340                 message = sd_bus_get_current_message(bus);
 341                 if (!message)
 342                         return 0;
 343
 344                 r = sd_bus_query_sender_creds(message, SD_BUS_CREDS_SESSION|SD_BUS_CREDS_AUGMENT, &creds);
 345                 if (r < 0)
 346                         return r;
 347
 348                 r = sd_bus_creds_get_session(creds, &name);
 349                 if (r < 0)
 350                         return r;
 351
 352                 session = hashmap_get(m->sessions, name);
 353                 if (!session)
 354                         return 0;
 355
 356                 seat = session->seat;
 357         } else {
 358                 _cleanup_free_ char *e = NULL;
 359                 const char *p;
 360
 361                 p = startswith(path, "/org/freedesktop/login1/seat/");
 362                 if (!p)
 363                         return 0;
 364
 365                 e = bus_label_unescape(p);
 366                 if (!e)
 367                         return -ENOMEM;
 368
 369                 seat = hashmap_get(m->seats, e);
 370         }
 371
 372         if (!seat)
 373                 return 0;
 374
 375         *found = seat;
 376         return 1;
 377 }
 378
 379 char *seat_bus_path(Seat *s) {
 380         _cleanup_free_ char *t = NULL;
 381
 382         assert(s);
 383
 384         t = bus_label_escape(s->id);
 385         if (!t)
 386                 return NULL;
 387
 388         return strappend("/org/freedesktop/login1/seat/", t);
 389 }
 390
 391 int seat_node_enumerator(sd_bus *bus, const char *path, void *userdata, char ***nodes, sd_bus_error *error) {
 392         _cleanup_strv_free_ char **l = NULL;
 393         sd_bus_message *message;
 394         Manager *m = userdata;
 395         Seat *seat;
 396         Iterator i;
 397         int r;
 398
 399         assert(bus);
 400         assert(path);
 401         assert(nodes);
 402
 403         HASHMAP_FOREACH(seat, m->seats, i) {
 404                 char *p;
 405
 406                 p = seat_bus_path(seat);
 407                 if (!p)
 408                         return -ENOMEM;
 409
 410                 r = strv_consume(&l, p);
 411                 if (r < 0)
 412                         return r;
 413         }
 414
 415         message = sd_bus_get_current_message(bus);
 416         if (message) {
 417                 _cleanup_(sd_bus_creds_unrefp) sd_bus_creds *creds = NULL;
 418                 const char *name;
 419                 Session *session;
 420
 421                 r = sd_bus_query_sender_creds(message, SD_BUS_CREDS_SESSION|SD_BUS_CREDS_AUGMENT, &creds);
 422                 if (r >= 0) {
 423                         r = sd_bus_creds_get_session(creds, &name);
 424                         if (r >= 0) {
 425                                 session = hashmap_get(m->sessions, name);
 426                                 if (session && session->seat) {
 427                                         r = strv_extend(&l, "/org/freedesktop/login1/seat/self");
 428                                         if (r < 0)
 429                                                 return r;
 430                                 }
 431                         }
 432                 }
 433         }
 434
 435         *nodes = l;
 436         l = NULL;
 437
 438         return 1;
 439 }
 440
 441 int seat_send_signal(Seat *s, bool new_seat) {
 442         _cleanup_free_ char *p = NULL;
 443
 444         assert(s);
 445
 446         p = seat_bus_path(s);
 447         if (!p)
 448                 return -ENOMEM;
 449
 450         return sd_bus_emit_signal(
 451                         s->manager->bus,
 452                         "/org/freedesktop/login1",
 453                         "org.freedesktop.login1.Manager",
 454                         new_seat ? "SeatNew" : "SeatRemoved",
 455                         "so", s->id, p);
 456 }
 457
 458 int seat_send_changed(Seat *s, const char *properties, ...) {
 459         _cleanup_free_ char *p = NULL;
 460         char **l;
 461
 462         assert(s);
 463
 464         if (!s->started)
 465                 return 0;
 466
 467         p = seat_bus_path(s);
 468         if (!p)
 469                 return -ENOMEM;
 470
 471         l = strv_from_stdarg_alloca(properties);
 472
 473         return sd_bus_emit_properties_changed_strv(s->manager->bus, p, "org.freedesktop.login1.Seat", l);
 474 }