src/login/logind-seat-dbus.c

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2011 Lennart Poettering
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU General Public License as published by
  10   the Free Software Foundation; either version 2 of the License, or
  11   (at your option) any later version.
  12
  13   systemd is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   General Public License for more details.
  17
  18   You should have received a copy of the GNU General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include <errno.h>
  23 #include <string.h>
  24
  25 #include "logind.h"
  26 #include "logind-seat.h"
  27 #include "dbus-common.h"
  28 #include "util.h"
  29
  30 #define BUS_SEAT_INTERFACE \
  31         " <interface name=\"org.freedesktop.login1.Seat\">\n"           \
  32         "  <method name=\"Terminate\"/>\n"                              \
  33         "  <method name=\"ActivateSession\">\n"                         \
  34         "   <arg name=\"id\" type=\"s\"/>\n"                            \
  35         "  </method>\n"                                                 \
  36         "  <property name=\"Id\" type=\"s\" access=\"read\"/>\n"        \
  37         "  <property name=\"ActiveSession\" type=\"so\" access=\"read\"/>\n" \
  38         "  <property name=\"CanMultiSession\" type=\"b\" access=\"read\"/>\n" \
  39         "  <property name=\"Sessions\" type=\"a(so)\" access=\"read\"/>\n" \
  40         "  <property name=\"IdleHint\" type=\"b\" access=\"read\"/>\n"  \
  41         "  <property name=\"IdleSinceHint\" type=\"t\" access=\"read\"/>\n" \
  42         "  <property name=\"IdleSinceHintMonotonic\" type=\"t\" access=\"read\"/>\n" \
  43         " </interface>\n"                                               \
  44
  45 #define INTROSPECTION                                                   \
  46         DBUS_INTROSPECT_1_0_XML_DOCTYPE_DECL_NODE                       \
  47         "<node>\n"                                                      \
  48         BUS_SEAT_INTERFACE                                              \
  49         BUS_PROPERTIES_INTERFACE                                        \
  50         BUS_PEER_INTERFACE                                              \
  51         BUS_INTROSPECTABLE_INTERFACE                                    \
  52         "</node>\n"
  53
  54 #define INTERFACES_LIST                              \
  55         BUS_GENERIC_INTERFACES_LIST                  \
  56         "org.freedesktop.login1.Seat\0"
  57
  58 static int bus_seat_append_active(DBusMessageIter *i, const char *property, void *data) {
  59         DBusMessageIter sub;
  60         Seat *s = data;
  61         const char *id, *path;
  62         char *p = NULL;
  63
  64         assert(i);
  65         assert(property);
  66         assert(s);
  67
  68         if (!dbus_message_iter_open_container(i, DBUS_TYPE_STRUCT, NULL, &sub))
  69                 return -ENOMEM;
  70
  71         if (s->active) {
  72                 id = s->active->id;
  73                 path = p = session_bus_path(s->active);
  74
  75                 if (!p)
  76                         return -ENOMEM;
  77         } else {
  78                 id = "";
  79                 path = "/";
  80         }
  81
  82         if (!dbus_message_iter_append_basic(&sub, DBUS_TYPE_STRING, &id) ||
  83             !dbus_message_iter_append_basic(&sub, DBUS_TYPE_OBJECT_PATH, &path)) {
  84                 free(p);
  85                 return -ENOMEM;
  86         }
  87
  88         free(p);
  89
  90         if (!dbus_message_iter_close_container(i, &sub))
  91                 return -ENOMEM;
  92
  93         return 0;
  94 }
  95
  96 static int bus_seat_append_sessions(DBusMessageIter *i, const char *property, void *data) {
  97         DBusMessageIter sub, sub2;
  98         Seat *s = data;
  99         Session *session;
 100
 101         assert(i);
 102         assert(property);
 103         assert(s);
 104
 105         if (!dbus_message_iter_open_container(i, DBUS_TYPE_ARRAY, "(so)", &sub))
 106                 return -ENOMEM;
 107
 108         LIST_FOREACH(sessions_by_seat, session, s->sessions) {
 109                 char *p;
 110
 111                 if (!dbus_message_iter_open_container(&sub, DBUS_TYPE_STRUCT, NULL, &sub2))
 112                         return -ENOMEM;
 113
 114                 p = session_bus_path(session);
 115                 if (!p)
 116                         return -ENOMEM;
 117
 118                 if (!dbus_message_iter_append_basic(&sub2, DBUS_TYPE_STRING, &session->id) ||
 119                     !dbus_message_iter_append_basic(&sub2, DBUS_TYPE_OBJECT_PATH, &p)) {
 120                         free(p);
 121                         return -ENOMEM;
 122                 }
 123
 124                 free(p);
 125
 126                 if (!dbus_message_iter_close_container(&sub, &sub2))
 127                         return -ENOMEM;
 128         }
 129
 130         if (!dbus_message_iter_close_container(i, &sub))
 131                 return -ENOMEM;
 132
 133         return 0;
 134 }
 135
 136 static int bus_seat_append_multi_session(DBusMessageIter *i, const char *property, void *data) {
 137         Seat *s = data;
 138         dbus_bool_t b;
 139
 140         assert(i);
 141         assert(property);
 142         assert(s);
 143
 144         b = seat_can_multi_session(s);
 145
 146         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_BOOLEAN, &b))
 147                 return -ENOMEM;
 148
 149         return 0;
 150 }
 151
 152 static int bus_seat_append_idle_hint(DBusMessageIter *i, const char *property, void *data) {
 153         Seat *s = data;
 154         dbus_bool_t b;
 155
 156         assert(i);
 157         assert(property);
 158         assert(s);
 159
 160         b = seat_get_idle_hint(s, NULL) > 0;
 161         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_BOOLEAN, &b))
 162                 return -ENOMEM;
 163
 164         return 0;
 165 }
 166
 167 static int bus_seat_append_idle_hint_since(DBusMessageIter *i, const char *property, void *data) {
 168         Seat *s = data;
 169         dual_timestamp t;
 170         uint64_t k;
 171
 172         assert(i);
 173         assert(property);
 174         assert(s);
 175
 176         seat_get_idle_hint(s, &t);
 177         k = streq(property, "IdleSinceHint") ? t.realtime : t.monotonic;
 178
 179         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_UINT64, &k))
 180                 return -ENOMEM;
 181
 182         return 0;
 183 }
 184
 185 static int get_seat_for_path(Manager *m, const char *path, Seat **_s) {
 186         Seat *s;
 187         char *id;
 188
 189         assert(m);
 190         assert(path);
 191         assert(_s);
 192
 193         if (!startswith(path, "/org/freedesktop/login1/seat/"))
 194                 return -EINVAL;
 195
 196         id = bus_path_unescape(path + 29);
 197         if (!id)
 198                 return -ENOMEM;
 199
 200         s = hashmap_get(m->seats, id);
 201         free(id);
 202
 203         if (!s)
 204                 return -ENOENT;
 205
 206         *_s = s;
 207         return 0;
 208 }
 209
 210 static const BusProperty bus_login_seat_properties[] = {
 211         { "Id",                     bus_property_append_string,      "s", offsetof(Seat, id), true },
 212         { "ActiveSession",          bus_seat_append_active,       "(so)", 0 },
 213         { "CanMultiSession",        bus_seat_append_multi_session,   "b", 0 },
 214         { "Sessions",               bus_seat_append_sessions,    "a(so)", 0 },
 215         { "IdleHint",               bus_seat_append_idle_hint,       "b", 0 },
 216         { "IdleSinceHint",          bus_seat_append_idle_hint_since, "t", 0 },
 217         { "IdleSinceHintMonotonic", bus_seat_append_idle_hint_since, "t", 0 },
 218         { NULL, }
 219 };
 220
 221 static DBusHandlerResult seat_message_dispatch(
 222                 Seat *s,
 223                 DBusConnection *connection,
 224                 DBusMessage *message) {
 225
 226         DBusError error;
 227         DBusMessage *reply = NULL;
 228         int r;
 229
 230         assert(s);
 231         assert(connection);
 232         assert(message);
 233
 234         dbus_error_init(&error);
 235
 236         if (dbus_message_is_method_call(message, "org.freedesktop.login1.Seat", "Terminate")) {
 237
 238                 r = seat_stop_sessions(s);
 239                 if (r < 0)
 240                         return bus_send_error_reply(connection, message, NULL, r);
 241
 242                 reply = dbus_message_new_method_return(message);
 243                 if (!reply)
 244                         goto oom;
 245
 246         } else if (dbus_message_is_method_call(message, "org.freedesktop.login1.Seat", "ActivateSession")) {
 247                 const char *name;
 248                 Session *session;
 249
 250                 if (!dbus_message_get_args(
 251                                     message,
 252                                     &error,
 253                                     DBUS_TYPE_STRING, &name,
 254                                     DBUS_TYPE_INVALID))
 255                         return bus_send_error_reply(connection, message, &error, -EINVAL);
 256
 257                 session = hashmap_get(s->manager->sessions, name);
 258                 if (!session || session->seat != s)
 259                         return bus_send_error_reply(connection, message, &error, -ENOENT);
 260
 261                 r = session_activate(session);
 262                 if (r < 0)
 263                         return bus_send_error_reply(connection, message, NULL, r);
 264
 265                 reply = dbus_message_new_method_return(message);
 266                 if (!reply)
 267                         goto oom;
 268         } else {
 269                 const BusBoundProperties bps[] = {
 270                         { "org.freedesktop.login1.Seat", bus_login_seat_properties, s },
 271                         { NULL, }
 272                 };
 273                 return bus_default_message_handler(connection, message, INTROSPECTION, INTERFACES_LIST, bps);
 274         }
 275
 276         if (reply) {
 277                 if (!dbus_connection_send(connection, reply, NULL))
 278                         goto oom;
 279
 280                 dbus_message_unref(reply);
 281         }
 282
 283         return DBUS_HANDLER_RESULT_HANDLED;
 284
 285 oom:
 286         if (reply)
 287                 dbus_message_unref(reply);
 288
 289         dbus_error_free(&error);
 290
 291         return DBUS_HANDLER_RESULT_NEED_MEMORY;
 292 }
 293
 294 static DBusHandlerResult seat_message_handler(
 295                 DBusConnection *connection,
 296                 DBusMessage *message,
 297                 void *userdata) {
 298
 299         Manager *m = userdata;
 300         Seat *s;
 301         int r;
 302
 303         r = get_seat_for_path(m, dbus_message_get_path(message), &s);
 304         if (r < 0) {
 305
 306                 if (r == -ENOMEM)
 307                         return DBUS_HANDLER_RESULT_NEED_MEMORY;
 308
 309                 if (r == -ENOENT) {
 310                         DBusError e;
 311
 312                         dbus_error_init(&e);
 313                         dbus_set_error_const(&e, DBUS_ERROR_UNKNOWN_OBJECT, "Unknown seat");
 314                         return bus_send_error_reply(connection, message, &e, r);
 315                 }
 316
 317                 return bus_send_error_reply(connection, message, NULL, r);
 318         }
 319
 320         return seat_message_dispatch(s, connection, message);
 321 }
 322
 323 const DBusObjectPathVTable bus_seat_vtable = {
 324         .message_function = seat_message_handler
 325 };
 326
 327 char *seat_bus_path(Seat *s) {
 328         char *t, *r;
 329
 330         assert(s);
 331
 332         t = bus_path_escape(s->id);
 333         if (!t)
 334                 return NULL;
 335
 336         r = strappend("/org/freedesktop/login1/seat/", t);
 337         free(t);
 338
 339         return r;
 340 }
 341
 342 int seat_send_signal(Seat *s, bool new_seat) {
 343         DBusMessage *m;
 344         int r = -ENOMEM;
 345         char *p = NULL;
 346
 347         assert(s);
 348
 349         m = dbus_message_new_signal("/org/freedesktop/login1",
 350                                     "org.freedesktop.login1.Manager",
 351                                     new_seat ? "SeatNew" : "SeatRemoved");
 352
 353         if (!m)
 354                 return -ENOMEM;
 355
 356         p = seat_bus_path(s);
 357         if (!p)
 358                 goto finish;
 359
 360         if (!dbus_message_append_args(
 361                             m,
 362                             DBUS_TYPE_STRING, &s->id,
 363                             DBUS_TYPE_OBJECT_PATH, &p,
 364                             DBUS_TYPE_INVALID))
 365                 goto finish;
 366
 367         if (!dbus_connection_send(s->manager->bus, m, NULL))
 368                 goto finish;
 369
 370         r = 0;
 371
 372 finish:
 373         dbus_message_unref(m);
 374         free(p);
 375
 376         return r;
 377 }
 378
 379 int seat_send_changed(Seat *s, const char *properties) {
 380         DBusMessage *m;
 381         int r = -ENOMEM;
 382         char *p = NULL;
 383
 384         assert(s);
 385
 386         if (!s->started)
 387                 return 0;
 388
 389         p = seat_bus_path(s);
 390         if (!p)
 391                 return -ENOMEM;
 392
 393         m = bus_properties_changed_new(p, "org.freedesktop.login1.Seat", properties);
 394         if (!m)
 395                 goto finish;
 396
 397         if (!dbus_connection_send(s->manager->bus, m, NULL))
 398                 goto finish;
 399
 400         r = 0;
 401
 402 finish:
 403         if (m)
 404                 dbus_message_unref(m);
 405         free(p);
 406
 407         return r;
 408 }