src/dbus.c

   1 /*-*- Mode: C; c-basic-offset: 8 -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2010 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 <sys/epoll.h>
  23 #include <sys/timerfd.h>
  24 #include <errno.h>
  25 #include <unistd.h>
  26 #include <dbus/dbus.h>
  27
  28 #include "dbus.h"
  29 #include "log.h"
  30 #include "strv.h"
  31 #include "cgroup.h"
  32 #include "dbus-unit.h"
  33 #include "dbus-job.h"
  34 #include "dbus-manager.h"
  35 #include "dbus-service.h"
  36 #include "dbus-socket.h"
  37 #include "dbus-target.h"
  38 #include "dbus-device.h"
  39 #include "dbus-mount.h"
  40 #include "dbus-automount.h"
  41 #include "dbus-snapshot.h"
  42 #include "dbus-swap.h"
  43 #include "dbus-timer.h"
  44 #include "dbus-path.h"
  45
  46 static const char bus_properties_interface[] = BUS_PROPERTIES_INTERFACE;
  47 static const char bus_introspectable_interface[] = BUS_INTROSPECTABLE_INTERFACE;
  48
  49 const char *const bus_interface_table[] = {
  50         "org.freedesktop.DBus.Properties",     bus_properties_interface,
  51         "org.freedesktop.DBus.Introspectable", bus_introspectable_interface,
  52         "org.freedesktop.systemd1.Manager",    bus_manager_interface,
  53         "org.freedesktop.systemd1.Job",        bus_job_interface,
  54         "org.freedesktop.systemd1.Unit",       bus_unit_interface,
  55         "org.freedesktop.systemd1.Service",    bus_service_interface,
  56         "org.freedesktop.systemd1.Socket",     bus_socket_interface,
  57         "org.freedesktop.systemd1.Target",     bus_target_interface,
  58         "org.freedesktop.systemd1.Device",     bus_device_interface,
  59         "org.freedesktop.systemd1.Mount",      bus_mount_interface,
  60         "org.freedesktop.systemd1.Automount",  bus_automount_interface,
  61         "org.freedesktop.systemd1.Snapshot",   bus_snapshot_interface,
  62         "org.freedesktop.systemd1.Swap",       bus_swap_interface,
  63         "org.freedesktop.systemd1.Timer",      bus_timer_interface,
  64         "org.freedesktop.systemd1.Path",       bus_path_interface,
  65         NULL
  66 };
  67
  68 static const char *error_to_dbus(int error);
  69
  70 static void api_bus_dispatch_status(DBusConnection *bus, DBusDispatchStatus status, void *data)  {
  71         Manager *m = data;
  72
  73         assert(bus);
  74         assert(m);
  75
  76         if (!m->api_bus)
  77                 return;
  78
  79         assert(m->api_bus == bus);
  80
  81         m->request_api_bus_dispatch = status != DBUS_DISPATCH_COMPLETE;
  82 }
  83
  84 static void system_bus_dispatch_status(DBusConnection *bus, DBusDispatchStatus status, void *data)  {
  85         Manager *m = data;
  86
  87         assert(bus);
  88         assert(m);
  89
  90         if (!m->system_bus)
  91                 return;
  92
  93         assert(m->system_bus == bus);
  94
  95         m->request_system_bus_dispatch = status != DBUS_DISPATCH_COMPLETE;
  96 }
  97
  98 static uint32_t bus_flags_to_events(DBusWatch *bus_watch) {
  99         unsigned flags;
 100         uint32_t events = 0;
 101
 102         assert(bus_watch);
 103
 104         /* no watch flags for disabled watches */
 105         if (!dbus_watch_get_enabled(bus_watch))
 106                 return 0;
 107
 108         flags = dbus_watch_get_flags(bus_watch);
 109
 110         if (flags & DBUS_WATCH_READABLE)
 111                 events |= EPOLLIN;
 112         if (flags & DBUS_WATCH_WRITABLE)
 113                 events |= EPOLLOUT;
 114
 115         return events | EPOLLHUP | EPOLLERR;
 116 }
 117
 118 static unsigned events_to_bus_flags(uint32_t events) {
 119         unsigned flags = 0;
 120
 121         if (events & EPOLLIN)
 122                 flags |= DBUS_WATCH_READABLE;
 123         if (events & EPOLLOUT)
 124                 flags |= DBUS_WATCH_WRITABLE;
 125         if (events & EPOLLHUP)
 126                 flags |= DBUS_WATCH_HANGUP;
 127         if (events & EPOLLERR)
 128                 flags |= DBUS_WATCH_ERROR;
 129
 130         return flags;
 131 }
 132
 133 void bus_watch_event(Manager *m, Watch *w, int events) {
 134         assert(m);
 135         assert(w);
 136
 137         /* This is called by the event loop whenever there is
 138          * something happening on D-Bus' file handles. */
 139
 140         if (!dbus_watch_get_enabled(w->data.bus_watch))
 141                 return;
 142
 143         dbus_watch_handle(w->data.bus_watch, events_to_bus_flags(events));
 144 }
 145
 146 static dbus_bool_t bus_add_watch(DBusWatch *bus_watch, void *data) {
 147         Manager *m = data;
 148         Watch *w;
 149         struct epoll_event ev;
 150
 151         assert(bus_watch);
 152         assert(m);
 153
 154         if (!(w = new0(Watch, 1)))
 155                 return FALSE;
 156
 157         w->fd = dbus_watch_get_unix_fd(bus_watch);
 158         w->type = WATCH_DBUS_WATCH;
 159         w->data.bus_watch = bus_watch;
 160
 161         zero(ev);
 162         ev.events = bus_flags_to_events(bus_watch);
 163         ev.data.ptr = w;
 164
 165         if (epoll_ctl(m->epoll_fd, EPOLL_CTL_ADD, w->fd, &ev) < 0) {
 166
 167                 if (errno != EEXIST) {
 168                         free(w);
 169                         return FALSE;
 170                 }
 171
 172                 /* Hmm, bloody D-Bus creates multiple watches on the
 173                  * same fd. epoll() does not like that. As a dirty
 174                  * hack we simply dup() the fd and hence get a second
 175                  * one we can safely add to the epoll(). */
 176
 177                 if ((w->fd = dup(w->fd)) < 0) {
 178                         free(w);
 179                         return FALSE;
 180                 }
 181
 182                 if (epoll_ctl(m->epoll_fd, EPOLL_CTL_ADD, w->fd, &ev) < 0) {
 183                         free(w);
 184                         close_nointr_nofail(w->fd);
 185                         return FALSE;
 186                 }
 187
 188                 w->fd_is_dupped = true;
 189         }
 190
 191         dbus_watch_set_data(bus_watch, w, NULL);
 192
 193         return TRUE;
 194 }
 195
 196 static void bus_remove_watch(DBusWatch *bus_watch, void *data) {
 197         Manager *m = data;
 198         Watch *w;
 199
 200         assert(bus_watch);
 201         assert(m);
 202
 203         if (!(w = dbus_watch_get_data(bus_watch)))
 204                 return;
 205
 206         assert(w->type == WATCH_DBUS_WATCH);
 207         assert_se(epoll_ctl(m->epoll_fd, EPOLL_CTL_DEL, w->fd, NULL) >= 0);
 208
 209         if (w->fd_is_dupped)
 210                 close_nointr_nofail(w->fd);
 211
 212         free(w);
 213 }
 214
 215 static void bus_toggle_watch(DBusWatch *bus_watch, void *data) {
 216         Manager *m = data;
 217         Watch *w;
 218         struct epoll_event ev;
 219
 220         assert(bus_watch);
 221         assert(m);
 222
 223         assert_se(w = dbus_watch_get_data(bus_watch));
 224         assert(w->type == WATCH_DBUS_WATCH);
 225
 226         zero(ev);
 227         ev.events = bus_flags_to_events(bus_watch);
 228         ev.data.ptr = w;
 229
 230         assert_se(epoll_ctl(m->epoll_fd, EPOLL_CTL_MOD, w->fd, &ev) == 0);
 231 }
 232
 233 static int bus_timeout_arm(Manager *m, Watch *w) {
 234         struct itimerspec its;
 235
 236         assert(m);
 237         assert(w);
 238
 239         zero(its);
 240
 241         if (dbus_timeout_get_enabled(w->data.bus_timeout)) {
 242                 timespec_store(&its.it_value, dbus_timeout_get_interval(w->data.bus_timeout) * USEC_PER_MSEC);
 243                 its.it_interval = its.it_interval;
 244         }
 245
 246         if (timerfd_settime(w->fd, 0, &its, NULL) < 0)
 247                 return -errno;
 248
 249         return 0;
 250 }
 251
 252 void bus_timeout_event(Manager *m, Watch *w, int events) {
 253         assert(m);
 254         assert(w);
 255
 256         /* This is called by the event loop whenever there is
 257          * something happening on D-Bus' file handles. */
 258
 259         if (!(dbus_timeout_get_enabled(w->data.bus_timeout)))
 260                 return;
 261
 262         dbus_timeout_handle(w->data.bus_timeout);
 263 }
 264
 265 static dbus_bool_t bus_add_timeout(DBusTimeout *timeout, void *data) {
 266         Manager *m = data;
 267         Watch *w;
 268         struct epoll_event ev;
 269
 270         assert(timeout);
 271         assert(m);
 272
 273         if (!(w = new0(Watch, 1)))
 274                 return FALSE;
 275
 276         if (!(w->fd = timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK|TFD_CLOEXEC)) < 0)
 277                 goto fail;
 278
 279         w->type = WATCH_DBUS_TIMEOUT;
 280         w->data.bus_timeout = timeout;
 281
 282         if (bus_timeout_arm(m, w) < 0)
 283                 goto fail;
 284
 285         zero(ev);
 286         ev.events = EPOLLIN;
 287         ev.data.ptr = w;
 288
 289         if (epoll_ctl(m->epoll_fd, EPOLL_CTL_ADD, w->fd, &ev) < 0)
 290                 goto fail;
 291
 292         dbus_timeout_set_data(timeout, w, NULL);
 293
 294         return TRUE;
 295
 296 fail:
 297         if (w->fd >= 0)
 298                 close_nointr_nofail(w->fd);
 299
 300         free(w);
 301         return FALSE;
 302 }
 303
 304 static void bus_remove_timeout(DBusTimeout *timeout, void *data) {
 305         Manager *m = data;
 306         Watch *w;
 307
 308         assert(timeout);
 309         assert(m);
 310
 311         if (!(w = dbus_timeout_get_data(timeout)))
 312                 return;
 313
 314         assert(w->type == WATCH_DBUS_TIMEOUT);
 315         assert_se(epoll_ctl(m->epoll_fd, EPOLL_CTL_DEL, w->fd, NULL) >= 0);
 316         close_nointr_nofail(w->fd);
 317         free(w);
 318 }
 319
 320 static void bus_toggle_timeout(DBusTimeout *timeout, void *data) {
 321         Manager *m = data;
 322         Watch *w;
 323         int r;
 324
 325         assert(timeout);
 326         assert(m);
 327
 328         assert_se(w = dbus_timeout_get_data(timeout));
 329         assert(w->type == WATCH_DBUS_TIMEOUT);
 330
 331         if ((r = bus_timeout_arm(m, w)) < 0)
 332                 log_error("Failed to rearm timer: %s", strerror(-r));
 333 }
 334
 335 static DBusHandlerResult api_bus_message_filter(DBusConnection  *connection, DBusMessage  *message, void *data) {
 336         Manager *m = data;
 337         DBusError error;
 338         DBusMessage *reply = NULL;
 339
 340         assert(connection);
 341         assert(message);
 342         assert(m);
 343
 344         dbus_error_init(&error);
 345
 346         /* log_debug("Got D-Bus request: %s.%s() on %s", */
 347         /*           dbus_message_get_interface(message), */
 348         /*           dbus_message_get_member(message), */
 349         /*           dbus_message_get_path(message)); */
 350
 351         if (dbus_message_is_signal(message, DBUS_INTERFACE_LOCAL, "Disconnected")) {
 352                 log_error("Warning! API D-Bus connection terminated.");
 353                 bus_done_api(m);
 354
 355         } else if (dbus_message_is_signal(message, DBUS_INTERFACE_DBUS, "NameOwnerChanged")) {
 356                 const char *name, *old_owner, *new_owner;
 357
 358                 if (!dbus_message_get_args(message, &error,
 359                                            DBUS_TYPE_STRING, &name,
 360                                            DBUS_TYPE_STRING, &old_owner,
 361                                            DBUS_TYPE_STRING, &new_owner,
 362                                            DBUS_TYPE_INVALID))
 363                         log_error("Failed to parse NameOwnerChanged message: %s", error.message);
 364                 else  {
 365                         if (set_remove(m->subscribed, (char*) name))
 366                                 log_debug("Subscription client vanished: %s (left: %u)", name, set_size(m->subscribed));
 367
 368                         if (old_owner[0] == 0)
 369                                 old_owner = NULL;
 370
 371                         if (new_owner[0] == 0)
 372                                 new_owner = NULL;
 373
 374                         manager_dispatch_bus_name_owner_changed(m, name, old_owner, new_owner);
 375                 }
 376         } else if (dbus_message_is_signal(message, "org.freedesktop.systemd1.Activator", "ActivationRequest")) {
 377                 const char *name;
 378
 379                 if (!dbus_message_get_args(message, &error,
 380                                            DBUS_TYPE_STRING, &name,
 381                                            DBUS_TYPE_INVALID))
 382                         log_error("Failed to parse ActivationRequest message: %s", error.message);
 383                 else  {
 384                         int r;
 385                         Unit *u;
 386
 387                         log_debug("Got D-Bus activation request for %s", name);
 388
 389                         r = manager_load_unit(m, name, NULL, &u);
 390
 391                         if (r >= 0 && u->meta.only_by_dependency)
 392                                 r = -EPERM;
 393
 394                         if (r >= 0)
 395                                 r = manager_add_job(m, JOB_START, u, JOB_REPLACE, true, NULL);
 396
 397                         if (r < 0) {
 398                                 const char *id, *text;
 399
 400                                 if (!(reply = dbus_message_new_signal("/org/freedesktop/systemd1", "org.freedesktop.systemd1.Activator", "ActivationFailure")))
 401                                         goto oom;
 402
 403                                 id = error_to_dbus(r);
 404                                 text = strerror(-r);
 405
 406                                 if (!dbus_message_set_destination(reply, DBUS_SERVICE_DBUS) ||
 407                                     !dbus_message_append_args(reply,
 408                                                               DBUS_TYPE_STRING, &name,
 409                                                               DBUS_TYPE_STRING, &id,
 410                                                               DBUS_TYPE_STRING, &text,
 411                                                               DBUS_TYPE_INVALID))
 412                                         goto oom;
 413                         }
 414
 415                         /* On success we don't do anything, the service will be spwaned now */
 416                 }
 417         }
 418
 419         dbus_error_free(&error);
 420
 421         if (reply) {
 422                 if (!dbus_connection_send(connection, reply, NULL))
 423                         goto oom;
 424
 425                 dbus_message_unref(reply);
 426         }
 427
 428         return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 429
 430 oom:
 431         if (reply)
 432                 dbus_message_unref(reply);
 433
 434         dbus_error_free(&error);
 435
 436         return DBUS_HANDLER_RESULT_NEED_MEMORY;
 437 }
 438
 439 static DBusHandlerResult system_bus_message_filter(DBusConnection  *connection, DBusMessage  *message, void *data) {
 440         Manager *m = data;
 441         DBusError error;
 442
 443         assert(connection);
 444         assert(message);
 445         assert(m);
 446
 447         dbus_error_init(&error);
 448
 449         /* log_debug("Got D-Bus request: %s.%s() on %s", */
 450         /*           dbus_message_get_interface(message), */
 451         /*           dbus_message_get_member(message), */
 452         /*           dbus_message_get_path(message)); */
 453
 454         if (dbus_message_is_signal(message, DBUS_INTERFACE_LOCAL, "Disconnected")) {
 455                 log_error("Warning! System D-Bus connection terminated.");
 456                 bus_done_system(m);
 457
 458         } if (dbus_message_is_signal(message, "org.freedesktop.systemd1.Agent", "Released")) {
 459                 const char *cgroup;
 460
 461                 if (!dbus_message_get_args(message, &error,
 462                                            DBUS_TYPE_STRING, &cgroup,
 463                                            DBUS_TYPE_INVALID))
 464                         log_error("Failed to parse Released message: %s", error.message);
 465                 else
 466                         cgroup_notify_empty(m, cgroup);
 467         }
 468
 469         dbus_error_free(&error);
 470         return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 471 }
 472
 473 unsigned bus_dispatch(Manager *m) {
 474         assert(m);
 475
 476         if (m->queued_message) {
 477                 /* If we cannot get rid of this message we won't
 478                  * dispatch any D-Bus messages, so that we won't end
 479                  * up wanting to queue another message. */
 480
 481                 if (!dbus_connection_send(m->api_bus, m->queued_message, NULL))
 482                         return 0;
 483
 484                 dbus_message_unref(m->queued_message);
 485                 m->queued_message = NULL;
 486         }
 487
 488         if (m->request_api_bus_dispatch) {
 489                 if (dbus_connection_dispatch(m->api_bus) == DBUS_DISPATCH_COMPLETE)
 490                         m->request_api_bus_dispatch = false;
 491
 492                 return 1;
 493         }
 494
 495         if (m->request_system_bus_dispatch) {
 496                 if (dbus_connection_dispatch(m->system_bus) == DBUS_DISPATCH_COMPLETE)
 497                         m->request_system_bus_dispatch = false;
 498
 499                 return 1;
 500         }
 501
 502         return 0;
 503 }
 504
 505 static void request_name_pending_cb(DBusPendingCall *pending, void *userdata) {
 506         DBusMessage *reply;
 507         DBusError error;
 508
 509         dbus_error_init(&error);
 510
 511         assert_se(reply = dbus_pending_call_steal_reply(pending));
 512
 513         switch (dbus_message_get_type(reply)) {
 514
 515         case DBUS_MESSAGE_TYPE_ERROR:
 516
 517                 assert_se(dbus_set_error_from_message(&error, reply));
 518                 log_warning("RequestName() failed: %s", error.message);
 519                 break;
 520
 521         case DBUS_MESSAGE_TYPE_METHOD_RETURN: {
 522                 uint32_t r;
 523
 524                 if (!dbus_message_get_args(reply,
 525                                            &error,
 526                                            DBUS_TYPE_UINT32, &r,
 527                                            DBUS_TYPE_INVALID)) {
 528                         log_error("Failed to parse RequestName() reply: %s", error.message);
 529                         break;
 530                 }
 531
 532                 if (r == 1)
 533                         log_debug("Successfully acquired name.");
 534                 else
 535                         log_error("Name already owned.");
 536
 537                 break;
 538         }
 539
 540         default:
 541                 assert_not_reached("Invalid reply message");
 542         }
 543
 544         dbus_message_unref(reply);
 545         dbus_error_free(&error);
 546 }
 547
 548 static int request_name(Manager *m) {
 549         const char *name = "org.freedesktop.systemd1";
 550         uint32_t flags = 0;
 551         DBusMessage *message = NULL;
 552         DBusPendingCall *pending = NULL;
 553
 554         if (!(message = dbus_message_new_method_call(
 555                               DBUS_SERVICE_DBUS,
 556                               DBUS_PATH_DBUS,
 557                               DBUS_INTERFACE_DBUS,
 558                               "RequestName")))
 559                 goto oom;
 560
 561         if (!dbus_message_append_args(
 562                             message,
 563                             DBUS_TYPE_STRING, &name,
 564                             DBUS_TYPE_UINT32, &flags,
 565                             DBUS_TYPE_INVALID))
 566                 goto oom;
 567
 568         if (!dbus_connection_send_with_reply(m->api_bus, message, &pending, -1))
 569                 goto oom;
 570
 571         if (!dbus_pending_call_set_notify(pending, request_name_pending_cb, m, NULL))
 572                 goto oom;
 573
 574         dbus_message_unref(message);
 575         dbus_pending_call_unref(pending);
 576
 577         /* We simple ask for the name and don't wait for it. Sooner or
 578          * later we'll have it. */
 579
 580         return 0;
 581
 582 oom:
 583         if (pending) {
 584                 dbus_pending_call_cancel(pending);
 585                 dbus_pending_call_unref(pending);
 586         }
 587
 588         if (message)
 589                 dbus_message_unref(message);
 590
 591         return -ENOMEM;
 592 }
 593
 594 static void query_name_list_pending_cb(DBusPendingCall *pending, void *userdata) {
 595         DBusMessage *reply;
 596         DBusError error;
 597         Manager *m = userdata;
 598
 599         assert(m);
 600
 601         dbus_error_init(&error);
 602
 603         assert_se(reply = dbus_pending_call_steal_reply(pending));
 604
 605         switch (dbus_message_get_type(reply)) {
 606
 607         case DBUS_MESSAGE_TYPE_ERROR:
 608
 609                 assert_se(dbus_set_error_from_message(&error, reply));
 610                 log_warning("ListNames() failed: %s", error.message);
 611                 break;
 612
 613         case DBUS_MESSAGE_TYPE_METHOD_RETURN: {
 614                 int r;
 615                 char **l;
 616
 617                 if ((r = bus_parse_strv(reply, &l)) < 0)
 618                         log_warning("Failed to parse ListNames() reply: %s", strerror(-r));
 619                 else {
 620                         char **t;
 621
 622                         STRV_FOREACH(t, l)
 623                                 /* This is a bit hacky, we say the
 624                                  * owner of the name is the name
 625                                  * itself, because we don't want the
 626                                  * extra traffic to figure out the
 627                                  * real owner. */
 628                                 manager_dispatch_bus_name_owner_changed(m, *t, NULL, *t);
 629
 630                         strv_free(l);
 631                 }
 632
 633                 break;
 634         }
 635
 636         default:
 637                 assert_not_reached("Invalid reply message");
 638         }
 639
 640         dbus_message_unref(reply);
 641         dbus_error_free(&error);
 642 }
 643
 644 static int query_name_list(Manager *m) {
 645         DBusMessage *message = NULL;
 646         DBusPendingCall *pending = NULL;
 647
 648         /* Asks for the currently installed bus names */
 649
 650         if (!(message = dbus_message_new_method_call(
 651                               DBUS_SERVICE_DBUS,
 652                               DBUS_PATH_DBUS,
 653                               DBUS_INTERFACE_DBUS,
 654                               "ListNames")))
 655                 goto oom;
 656
 657         if (!dbus_connection_send_with_reply(m->api_bus, message, &pending, -1))
 658                 goto oom;
 659
 660         if (!dbus_pending_call_set_notify(pending, query_name_list_pending_cb, m, NULL))
 661                 goto oom;
 662
 663         dbus_message_unref(message);
 664         dbus_pending_call_unref(pending);
 665
 666         /* We simple ask for the list and don't wait for it. Sooner or
 667          * later we'll get it. */
 668
 669         return 0;
 670
 671 oom:
 672         if (pending) {
 673                 dbus_pending_call_cancel(pending);
 674                 dbus_pending_call_unref(pending);
 675         }
 676
 677         if (message)
 678                 dbus_message_unref(message);
 679
 680         return -ENOMEM;
 681 }
 682
 683 static int bus_setup_loop(Manager *m, DBusConnection *bus) {
 684         assert(m);
 685         assert(bus);
 686
 687         dbus_connection_set_exit_on_disconnect(bus, FALSE);
 688
 689         if (!dbus_connection_set_watch_functions(bus, bus_add_watch, bus_remove_watch, bus_toggle_watch, m, NULL) ||
 690             !dbus_connection_set_timeout_functions(bus, bus_add_timeout, bus_remove_timeout, bus_toggle_timeout, m, NULL))
 691                 return -ENOMEM;
 692
 693         return 0;
 694 }
 695
 696 int bus_init_system(Manager *m) {
 697         DBusError error;
 698         char *id;
 699         int r;
 700
 701         assert(m);
 702
 703         dbus_error_init(&error);
 704
 705         if (m->system_bus)
 706                 return 0;
 707
 708         if (m->running_as != MANAGER_SESSION && m->api_bus)
 709                 m->system_bus = m->api_bus;
 710         else {
 711                 if (!(m->system_bus = dbus_bus_get_private(DBUS_BUS_SYSTEM, &error))) {
 712                         log_debug("Failed to get system D-Bus connection, retrying later: %s", error.message);
 713                         dbus_error_free(&error);
 714                         return 0;
 715                 }
 716
 717                 dbus_connection_set_dispatch_status_function(m->system_bus, system_bus_dispatch_status, m, NULL);
 718                 m->request_system_bus_dispatch = true;
 719
 720                 if ((r = bus_setup_loop(m, m->system_bus)) < 0) {
 721                         bus_done_system(m);
 722                         return r;
 723                 }
 724         }
 725
 726         if (!dbus_connection_add_filter(m->system_bus, system_bus_message_filter, m, NULL)) {
 727                 bus_done_system(m);
 728                 return -ENOMEM;
 729         }
 730
 731         dbus_bus_add_match(m->system_bus,
 732                            "type='signal',"
 733                            "interface='org.freedesktop.systemd1.Agent',"
 734                            "path='/org/freedesktop/systemd1/agent'",
 735                            &error);
 736
 737         if (dbus_error_is_set(&error)) {
 738                 log_error("Failed to register match: %s", error.message);
 739                 dbus_error_free(&error);
 740                 bus_done_system(m);
 741                 return -ENOMEM;
 742         }
 743
 744         log_debug("Successfully connected to system D-Bus bus %s as %s",
 745                   strnull((id = dbus_connection_get_server_id(m->system_bus))),
 746                   strnull(dbus_bus_get_unique_name(m->system_bus)));
 747         dbus_free(id);
 748
 749         return 0;
 750 }
 751
 752 int bus_init_api(Manager *m) {
 753         DBusError error;
 754         char *id;
 755         int r;
 756
 757         assert(m);
 758
 759         dbus_error_init(&error);
 760
 761         if (m->api_bus)
 762                 return 0;
 763
 764         if (m->name_data_slot < 0)
 765                 if (!dbus_pending_call_allocate_data_slot(&m->name_data_slot))
 766                         return -ENOMEM;
 767
 768         if (m->running_as != MANAGER_SESSION && m->system_bus)
 769                 m->api_bus = m->system_bus;
 770         else {
 771                 if (!(m->api_bus = dbus_bus_get_private(m->running_as == MANAGER_SESSION ? DBUS_BUS_SESSION : DBUS_BUS_SYSTEM, &error))) {
 772                         log_debug("Failed to get API D-Bus connection, retrying later: %s", error.message);
 773                         dbus_error_free(&error);
 774                         return 0;
 775                 }
 776
 777                 dbus_connection_set_dispatch_status_function(m->api_bus, api_bus_dispatch_status, m, NULL);
 778                 m->request_api_bus_dispatch = true;
 779
 780                 if ((r = bus_setup_loop(m, m->api_bus)) < 0) {
 781                         bus_done_api(m);
 782                         return r;
 783                 }
 784         }
 785
 786         if (!dbus_connection_register_object_path(m->api_bus, "/org/freedesktop/systemd1", &bus_manager_vtable, m) ||
 787             !dbus_connection_register_fallback(m->api_bus, "/org/freedesktop/systemd1/unit", &bus_unit_vtable, m) ||
 788             !dbus_connection_register_fallback(m->api_bus, "/org/freedesktop/systemd1/job", &bus_job_vtable, m) ||
 789             !dbus_connection_add_filter(m->api_bus, api_bus_message_filter, m, NULL)) {
 790                 bus_done_api(m);
 791                 return -ENOMEM;
 792         }
 793
 794         /* Get NameOwnerChange messages */
 795         dbus_bus_add_match(m->api_bus,
 796                            "type='signal',"
 797                            "sender='"DBUS_SERVICE_DBUS"',"
 798                            "interface='"DBUS_INTERFACE_DBUS"',"
 799                            "path='"DBUS_PATH_DBUS"'",
 800                            &error);
 801
 802         if (dbus_error_is_set(&error)) {
 803                 log_error("Failed to register match: %s", error.message);
 804                 dbus_error_free(&error);
 805                 bus_done_api(m);
 806                 return -ENOMEM;
 807         }
 808
 809         /* Get activation requests */
 810         dbus_bus_add_match(m->api_bus,
 811                            "type='signal',"
 812                            "sender='"DBUS_SERVICE_DBUS"',"
 813                            "interface='org.freedesktop.systemd1.Activator',"
 814                            "path='"DBUS_PATH_DBUS"'",
 815                            &error);
 816
 817         if (dbus_error_is_set(&error)) {
 818                 log_error("Failed to register match: %s", error.message);
 819                 dbus_error_free(&error);
 820                 bus_done_api(m);
 821                 return -ENOMEM;
 822         }
 823
 824         if ((r = request_name(m)) < 0) {
 825                 bus_done_api(m);
 826                 return r;
 827         }
 828
 829         if ((r = query_name_list(m)) < 0) {
 830                 bus_done_api(m);
 831                 return r;
 832         }
 833
 834         log_debug("Successfully connected to API D-Bus bus %s as %s",
 835                   strnull((id = dbus_connection_get_server_id(m->api_bus))),
 836                   strnull(dbus_bus_get_unique_name(m->api_bus)));
 837         dbus_free(id);
 838
 839         if (!m->subscribed)
 840                 if (!(m->subscribed = set_new(string_hash_func, string_compare_func)))
 841                         return -ENOMEM;
 842
 843         return 0;
 844 }
 845
 846 void bus_done_api(Manager *m) {
 847         assert(m);
 848
 849         if (m->api_bus) {
 850                 if (m->system_bus == m->api_bus)
 851                         m->system_bus = NULL;
 852
 853                 dbus_connection_set_dispatch_status_function(m->api_bus, NULL, NULL, NULL);
 854                 dbus_connection_flush(m->api_bus);
 855                 dbus_connection_close(m->api_bus);
 856                 dbus_connection_unref(m->api_bus);
 857                 m->api_bus = NULL;
 858         }
 859
 860         if (m->subscribed) {
 861                 char *c;
 862
 863                 while ((c = set_steal_first(m->subscribed)))
 864                         free(c);
 865
 866                 set_free(m->subscribed);
 867                 m->subscribed = NULL;
 868         }
 869
 870        if (m->name_data_slot >= 0)
 871                dbus_pending_call_free_data_slot(&m->name_data_slot);
 872
 873        if (m->queued_message) {
 874                dbus_message_unref(m->queued_message);
 875                m->queued_message = NULL;
 876        }
 877 }
 878
 879 void bus_done_system(Manager *m) {
 880         assert(m);
 881
 882         if (m->system_bus == m->api_bus)
 883                 bus_done_api(m);
 884
 885         if (m->system_bus) {
 886                 dbus_connection_set_dispatch_status_function(m->system_bus, NULL, NULL, NULL);
 887                 dbus_connection_flush(m->system_bus);
 888                 dbus_connection_close(m->system_bus);
 889                 dbus_connection_unref(m->system_bus);
 890                 m->system_bus = NULL;
 891         }
 892 }
 893
 894 static void query_pid_pending_cb(DBusPendingCall *pending, void *userdata) {
 895         Manager *m = userdata;
 896         DBusMessage *reply;
 897         DBusError error;
 898         const char *name;
 899
 900         dbus_error_init(&error);
 901
 902         assert_se(name = dbus_pending_call_get_data(pending, m->name_data_slot));
 903         assert_se(reply = dbus_pending_call_steal_reply(pending));
 904
 905         switch (dbus_message_get_type(reply)) {
 906
 907         case DBUS_MESSAGE_TYPE_ERROR:
 908
 909                 assert_se(dbus_set_error_from_message(&error, reply));
 910                 log_warning("GetConnectionUnixProcessID() failed: %s", error.message);
 911                 break;
 912
 913         case DBUS_MESSAGE_TYPE_METHOD_RETURN: {
 914                 uint32_t r;
 915
 916                 if (!dbus_message_get_args(reply,
 917                                            &error,
 918                                            DBUS_TYPE_UINT32, &r,
 919                                            DBUS_TYPE_INVALID)) {
 920                         log_error("Failed to parse GetConnectionUnixProcessID() reply: %s", error.message);
 921                         break;
 922                 }
 923
 924                 manager_dispatch_bus_query_pid_done(m, name, (pid_t) r);
 925                 break;
 926         }
 927
 928         default:
 929                 assert_not_reached("Invalid reply message");
 930         }
 931
 932         dbus_message_unref(reply);
 933         dbus_error_free(&error);
 934 }
 935
 936 int bus_query_pid(Manager *m, const char *name) {
 937         DBusMessage *message = NULL;
 938         DBusPendingCall *pending = NULL;
 939         char *n = NULL;
 940
 941         assert(m);
 942         assert(name);
 943
 944         if (!(message = dbus_message_new_method_call(
 945                               DBUS_SERVICE_DBUS,
 946                               DBUS_PATH_DBUS,
 947                               DBUS_INTERFACE_DBUS,
 948                               "GetConnectionUnixProcessID")))
 949                 goto oom;
 950
 951         if (!(dbus_message_append_args(
 952                               message,
 953                               DBUS_TYPE_STRING, &name,
 954                               DBUS_TYPE_INVALID)))
 955                 goto oom;
 956
 957         if (!dbus_connection_send_with_reply(m->api_bus, message, &pending, -1))
 958                 goto oom;
 959
 960         if (!(n = strdup(name)))
 961                 goto oom;
 962
 963         if (!dbus_pending_call_set_data(pending, m->name_data_slot, n, free))
 964                 goto oom;
 965
 966         n = NULL;
 967
 968         if (!dbus_pending_call_set_notify(pending, query_pid_pending_cb, m, NULL))
 969                 goto oom;
 970
 971         dbus_message_unref(message);
 972         dbus_pending_call_unref(pending);
 973
 974         return 0;
 975
 976 oom:
 977         free(n);
 978
 979         if (pending) {
 980                 dbus_pending_call_cancel(pending);
 981                 dbus_pending_call_unref(pending);
 982         }
 983
 984         if (message)
 985                 dbus_message_unref(message);
 986
 987         return -ENOMEM;
 988 }
 989
 990 DBusHandlerResult bus_default_message_handler(Manager *m, DBusMessage *message, const char*introspection, const BusProperty *properties) {
 991         DBusError error;
 992         DBusMessage *reply = NULL;
 993         int r;
 994
 995         assert(m);
 996         assert(message);
 997
 998         dbus_error_init(&error);
 999
1000         if (dbus_message_is_method_call(message, "org.freedesktop.DBus.Introspectable", "Introspect") && introspection) {
1001
1002                 if (!(reply = dbus_message_new_method_return(message)))
1003                         goto oom;
1004
1005                 if (!dbus_message_append_args(reply, DBUS_TYPE_STRING, &introspection, DBUS_TYPE_INVALID))
1006                         goto oom;
1007
1008         } else if (dbus_message_is_method_call(message, "org.freedesktop.DBus.Properties", "Get") && properties) {
1009                 const char *interface, *property;
1010                 const BusProperty *p;
1011
1012                 if (!dbus_message_get_args(
1013                             message,
1014                             &error,
1015                             DBUS_TYPE_STRING, &interface,
1016                             DBUS_TYPE_STRING, &property,
1017                             DBUS_TYPE_INVALID))
1018                         return bus_send_error_reply(m, message, &error, -EINVAL);
1019
1020                 for (p = properties; p->property; p++)
1021                         if (streq(p->interface, interface) && streq(p->property, property))
1022                                 break;
1023
1024                 if (p->property) {
1025                         DBusMessageIter iter, sub;
1026
1027                         if (!(reply = dbus_message_new_method_return(message)))
1028                                 goto oom;
1029
1030                         dbus_message_iter_init_append(reply, &iter);
1031
1032                         if (!dbus_message_iter_open_container(&iter, DBUS_TYPE_VARIANT, p->signature, &sub))
1033                                 goto oom;
1034
1035                         if ((r = p->append(m, &sub, property, (void*) p->data)) < 0) {
1036
1037                                 if (r == -ENOMEM)
1038                                         goto oom;
1039
1040                                 dbus_message_unref(reply);
1041                                 return bus_send_error_reply(m, message, NULL, r);
1042                         }
1043
1044                         if (!dbus_message_iter_close_container(&iter, &sub))
1045                                 goto oom;
1046                 }
1047         } else if (dbus_message_is_method_call(message, "org.freedesktop.DBus.Properties", "GetAll") && properties) {
1048                 const char *interface;
1049                 const BusProperty *p;
1050                 DBusMessageIter iter, sub, sub2, sub3;
1051                 bool any = false;
1052
1053                 if (!dbus_message_get_args(
1054                             message,
1055                             &error,
1056                             DBUS_TYPE_STRING, &interface,
1057                             DBUS_TYPE_INVALID))
1058                         return bus_send_error_reply(m, message, &error, -EINVAL);
1059
1060                 if (!(reply = dbus_message_new_method_return(message)))
1061                         goto oom;
1062
1063                 dbus_message_iter_init_append(reply, &iter);
1064
1065                 if (!dbus_message_iter_open_container(&iter, DBUS_TYPE_ARRAY, "{sv}", &sub))
1066                         goto oom;
1067
1068                 for (p = properties; p->property; p++) {
1069                         if (!streq(p->interface, interface))
1070                                 continue;
1071
1072                         if (!dbus_message_iter_open_container(&sub, DBUS_TYPE_DICT_ENTRY, NULL, &sub2) ||
1073                             !dbus_message_iter_append_basic(&sub2, DBUS_TYPE_STRING, &p->property) ||
1074                             !dbus_message_iter_open_container(&sub2, DBUS_TYPE_VARIANT, p->signature, &sub3))
1075                                 goto oom;
1076
1077                         if ((r = p->append(m, &sub3, p->property, (void*) p->data)) < 0) {
1078
1079                                 if (r == -ENOMEM)
1080                                         goto oom;
1081
1082                                 dbus_message_unref(reply);
1083                                 return bus_send_error_reply(m, message, NULL, r);
1084                         }
1085
1086                         if (!dbus_message_iter_close_container(&sub2, &sub3) ||
1087                             !dbus_message_iter_close_container(&sub, &sub2))
1088                                 goto oom;
1089
1090                         any = true;
1091                 }
1092
1093                 if (!dbus_message_iter_close_container(&iter, &sub))
1094                         goto oom;
1095         }
1096
1097         if (reply) {
1098                 if (!dbus_connection_send(m->api_bus, reply, NULL))
1099                         goto oom;
1100
1101                 dbus_message_unref(reply);
1102                 return DBUS_HANDLER_RESULT_HANDLED;
1103         }
1104
1105         return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
1106
1107 oom:
1108         if (reply)
1109                 dbus_message_unref(reply);
1110
1111         dbus_error_free(&error);
1112
1113         return DBUS_HANDLER_RESULT_NEED_MEMORY;
1114 }
1115
1116 static const char *error_to_dbus(int error) {
1117
1118         switch(error) {
1119
1120         case -EINVAL:
1121                 return DBUS_ERROR_INVALID_ARGS;
1122
1123         case -ENOMEM:
1124                 return DBUS_ERROR_NO_MEMORY;
1125
1126         case -EPERM:
1127         case -EACCES:
1128                 return DBUS_ERROR_ACCESS_DENIED;
1129
1130         case -ESRCH:
1131                 return DBUS_ERROR_UNIX_PROCESS_ID_UNKNOWN;
1132
1133         case -ENOENT:
1134                 return DBUS_ERROR_FILE_NOT_FOUND;
1135
1136         case -EEXIST:
1137                 return DBUS_ERROR_FILE_EXISTS;
1138
1139         case -ETIMEDOUT:
1140                 return DBUS_ERROR_TIMEOUT;
1141
1142         case -EIO:
1143                 return DBUS_ERROR_IO_ERROR;
1144
1145         case -ENETRESET:
1146         case -ECONNABORTED:
1147         case -ECONNRESET:
1148                 return DBUS_ERROR_DISCONNECTED;
1149         }
1150
1151         return DBUS_ERROR_FAILED;
1152 }
1153
1154 DBusHandlerResult bus_send_error_reply(Manager *m, DBusMessage *message, DBusError *bus_error, int error) {
1155         DBusMessage *reply = NULL;
1156         const char *name, *text;
1157
1158         if (bus_error && dbus_error_is_set(bus_error)) {
1159                 name = bus_error->name;
1160                 text = bus_error->message;
1161         } else {
1162                 name = error_to_dbus(error);
1163                 text = strerror(-error);
1164         }
1165
1166         if (!(reply = dbus_message_new_error(message, name, text)))
1167                 goto oom;
1168
1169         if (!dbus_connection_send(m->api_bus, reply, NULL))
1170                 goto oom;
1171
1172         dbus_message_unref(reply);
1173
1174         if (bus_error)
1175                 dbus_error_free(bus_error);
1176
1177         return DBUS_HANDLER_RESULT_HANDLED;
1178
1179 oom:
1180         if (reply)
1181                 dbus_message_unref(reply);
1182
1183         if (bus_error)
1184                 dbus_error_free(bus_error);
1185
1186         return DBUS_HANDLER_RESULT_NEED_MEMORY;
1187 }
1188
1189 int bus_property_append_string(Manager *m, DBusMessageIter *i, const char *property, void *data) {
1190         const char *t = data;
1191
1192         assert(m);
1193         assert(i);
1194         assert(property);
1195
1196         if (!t)
1197                 t = "";
1198
1199         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_STRING, &t))
1200                 return -ENOMEM;
1201
1202         return 0;
1203 }
1204
1205 int bus_property_append_strv(Manager *m, DBusMessageIter *i, const char *property, void *data) {
1206         DBusMessageIter sub;
1207         char **t = data;
1208
1209         assert(m);
1210         assert(i);
1211         assert(property);
1212
1213         if (!dbus_message_iter_open_container(i, DBUS_TYPE_ARRAY, "s", &sub))
1214                 return -ENOMEM;
1215
1216         STRV_FOREACH(t, t)
1217                 if (!dbus_message_iter_append_basic(&sub, DBUS_TYPE_STRING, t))
1218                         return -ENOMEM;
1219
1220         if (!dbus_message_iter_close_container(i, &sub))
1221                 return -ENOMEM;
1222
1223         return 0;
1224 }
1225
1226 int bus_property_append_bool(Manager *m, DBusMessageIter *i, const char *property, void *data) {
1227         bool *b = data;
1228         dbus_bool_t db;
1229
1230         assert(m);
1231         assert(i);
1232         assert(property);
1233         assert(b);
1234
1235         db = *b;
1236
1237         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_BOOLEAN, &db))
1238                 return -ENOMEM;
1239
1240         return 0;
1241 }
1242
1243 int bus_property_append_uint64(Manager *m, DBusMessageIter *i, const char *property, void *data) {
1244         assert(m);
1245         assert(i);
1246         assert(property);
1247         assert(data);
1248
1249         /* Let's ensure that pid_t is actually 64bit, and hence this
1250          * function can be used for usec_t */
1251         assert_cc(sizeof(uint64_t) == sizeof(usec_t));
1252
1253         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_UINT64, data))
1254                 return -ENOMEM;
1255
1256         return 0;
1257 }
1258
1259 int bus_property_append_uint32(Manager *m, DBusMessageIter *i, const char *property, void *data) {
1260         assert(m);
1261         assert(i);
1262         assert(property);
1263         assert(data);
1264
1265         /* Let's ensure that pid_t and mode_t is actually 32bit, and
1266          * hence this function can be used for pid_t/mode_t */
1267         assert_cc(sizeof(uint32_t) == sizeof(pid_t));
1268         assert_cc(sizeof(uint32_t) == sizeof(mode_t));
1269         assert_cc(sizeof(uint32_t) == sizeof(unsigned));
1270
1271         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_UINT32, data))
1272                 return -ENOMEM;
1273
1274         return 0;
1275 }
1276
1277 int bus_property_append_int32(Manager *m, DBusMessageIter *i, const char *property, void *data) {
1278         assert(m);
1279         assert(i);
1280         assert(property);
1281         assert(data);
1282
1283         assert_cc(sizeof(int32_t) == sizeof(int));
1284
1285         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_INT32, data))
1286                 return -ENOMEM;
1287
1288         return 0;
1289 }
1290
1291 int bus_parse_strv(DBusMessage *m, char ***_l) {
1292         DBusMessageIter iter, sub;
1293         unsigned n = 0, i = 0;
1294         char **l;
1295
1296         assert(m);
1297         assert(_l);
1298
1299         if (!dbus_message_iter_init(m, &iter) ||
1300             dbus_message_iter_get_arg_type(&iter) != DBUS_TYPE_ARRAY ||
1301             dbus_message_iter_get_element_type(&iter) != DBUS_TYPE_STRING)
1302             return -EINVAL;
1303
1304         dbus_message_iter_recurse(&iter, &sub);
1305
1306         while (dbus_message_iter_get_arg_type(&sub) != DBUS_TYPE_INVALID) {
1307                 n++;
1308                 dbus_message_iter_next(&sub);
1309         }
1310
1311         if (!(l = new(char*, n+1)))
1312                 return -ENOMEM;
1313
1314         assert_se(dbus_message_iter_init(m, &iter));
1315         dbus_message_iter_recurse(&iter, &sub);
1316
1317         while (dbus_message_iter_get_arg_type(&sub) != DBUS_TYPE_INVALID) {
1318                 const char *s;
1319
1320                 assert_se(dbus_message_iter_get_arg_type(&sub) == DBUS_TYPE_STRING);
1321                 dbus_message_iter_get_basic(&sub, &s);
1322
1323                 if (!(l[i++] = strdup(s))) {
1324                         strv_free(l);
1325                         return -ENOMEM;
1326                 }
1327
1328                 dbus_message_iter_next(&sub);
1329         }
1330
1331         assert(i == n);
1332         l[i] = NULL;
1333
1334         if (_l)
1335                 *_l = l;
1336
1337         return 0;
1338 }