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