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                                 log_warning("D-Bus activation failed for %s: %s", name, strerror(-r));
 401
 402                                 if (!(reply = dbus_message_new_signal("/org/freedesktop/systemd1", "org.freedesktop.systemd1.Activator", "ActivationFailure")))
 403                                         goto oom;
 404
 405                                 id = error_to_dbus(r);
 406                                 text = strerror(-r);
 407
 408                                 if (!dbus_message_set_destination(reply, DBUS_SERVICE_DBUS) ||
 409                                     !dbus_message_append_args(reply,
 410                                                               DBUS_TYPE_STRING, &name,
 411                                                               DBUS_TYPE_STRING, &id,
 412                                                               DBUS_TYPE_STRING, &text,
 413                                                               DBUS_TYPE_INVALID))
 414                                         goto oom;
 415                         }
 416
 417                         /* On success we don't do anything, the service will be spwaned now */
 418                 }
 419         }
 420
 421         dbus_error_free(&error);
 422
 423         if (reply) {
 424                 if (!dbus_connection_send(connection, reply, NULL))
 425                         goto oom;
 426
 427                 dbus_message_unref(reply);
 428         }
 429
 430         return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 431
 432 oom:
 433         if (reply)
 434                 dbus_message_unref(reply);
 435
 436         dbus_error_free(&error);
 437
 438         return DBUS_HANDLER_RESULT_NEED_MEMORY;
 439 }
 440
 441 static DBusHandlerResult system_bus_message_filter(DBusConnection  *connection, DBusMessage  *message, void *data) {
 442         Manager *m = data;
 443         DBusError error;
 444
 445         assert(connection);
 446         assert(message);
 447         assert(m);
 448
 449         dbus_error_init(&error);
 450
 451         /* log_debug("Got D-Bus request: %s.%s() on %s", */
 452         /*           dbus_message_get_interface(message), */
 453         /*           dbus_message_get_member(message), */
 454         /*           dbus_message_get_path(message)); */
 455
 456         if (dbus_message_is_signal(message, DBUS_INTERFACE_LOCAL, "Disconnected")) {
 457                 log_error("Warning! System D-Bus connection terminated.");
 458                 bus_done_system(m);
 459
 460         } if (dbus_message_is_signal(message, "org.freedesktop.systemd1.Agent", "Released")) {
 461                 const char *cgroup;
 462
 463                 if (!dbus_message_get_args(message, &error,
 464                                            DBUS_TYPE_STRING, &cgroup,
 465                                            DBUS_TYPE_INVALID))
 466                         log_error("Failed to parse Released message: %s", error.message);
 467                 else
 468                         cgroup_notify_empty(m, cgroup);
 469         }
 470
 471         dbus_error_free(&error);
 472         return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 473 }
 474
 475 unsigned bus_dispatch(Manager *m) {
 476         assert(m);
 477
 478         if (m->queued_message) {
 479                 /* If we cannot get rid of this message we won't
 480                  * dispatch any D-Bus messages, so that we won't end
 481                  * up wanting to queue another message. */
 482
 483                 if (!dbus_connection_send(m->api_bus, m->queued_message, NULL))
 484                         return 0;
 485
 486                 dbus_message_unref(m->queued_message);
 487                 m->queued_message = NULL;
 488         }
 489
 490         if (m->request_api_bus_dispatch) {
 491                 if (dbus_connection_dispatch(m->api_bus) == DBUS_DISPATCH_COMPLETE)
 492                         m->request_api_bus_dispatch = false;
 493
 494                 return 1;
 495         }
 496
 497         if (m->request_system_bus_dispatch) {
 498                 if (dbus_connection_dispatch(m->system_bus) == DBUS_DISPATCH_COMPLETE)
 499                         m->request_system_bus_dispatch = false;
 500
 501                 return 1;
 502         }
 503
 504         return 0;
 505 }
 506
 507 static void request_name_pending_cb(DBusPendingCall *pending, void *userdata) {
 508         DBusMessage *reply;
 509         DBusError error;
 510
 511         dbus_error_init(&error);
 512
 513         assert_se(reply = dbus_pending_call_steal_reply(pending));
 514
 515         switch (dbus_message_get_type(reply)) {
 516
 517         case DBUS_MESSAGE_TYPE_ERROR:
 518
 519                 assert_se(dbus_set_error_from_message(&error, reply));
 520                 log_warning("RequestName() failed: %s", error.message);
 521                 break;
 522
 523         case DBUS_MESSAGE_TYPE_METHOD_RETURN: {
 524                 uint32_t r;
 525
 526                 if (!dbus_message_get_args(reply,
 527                                            &error,
 528                                            DBUS_TYPE_UINT32, &r,
 529                                            DBUS_TYPE_INVALID)) {
 530                         log_error("Failed to parse RequestName() reply: %s", error.message);
 531                         break;
 532                 }
 533
 534                 if (r == 1)
 535                         log_debug("Successfully acquired name.");
 536                 else
 537                         log_error("Name already owned.");
 538
 539                 break;
 540         }
 541
 542         default:
 543                 assert_not_reached("Invalid reply message");
 544         }
 545
 546         dbus_message_unref(reply);
 547         dbus_error_free(&error);
 548 }
 549
 550 static int request_name(Manager *m) {
 551         const char *name = "org.freedesktop.systemd1";
 552         uint32_t flags = 0;
 553         DBusMessage *message = NULL;
 554         DBusPendingCall *pending = NULL;
 555
 556         if (!(message = dbus_message_new_method_call(
 557                               DBUS_SERVICE_DBUS,
 558                               DBUS_PATH_DBUS,
 559                               DBUS_INTERFACE_DBUS,
 560                               "RequestName")))
 561                 goto oom;
 562
 563         if (!dbus_message_append_args(
 564                             message,
 565                             DBUS_TYPE_STRING, &name,
 566                             DBUS_TYPE_UINT32, &flags,
 567                             DBUS_TYPE_INVALID))
 568                 goto oom;
 569
 570         if (!dbus_connection_send_with_reply(m->api_bus, message, &pending, -1))
 571                 goto oom;
 572
 573         if (!dbus_pending_call_set_notify(pending, request_name_pending_cb, m, NULL))
 574                 goto oom;
 575
 576         dbus_message_unref(message);
 577         dbus_pending_call_unref(pending);
 578
 579         /* We simple ask for the name and don't wait for it. Sooner or
 580          * later we'll have it. */
 581
 582         return 0;
 583
 584 oom:
 585         if (pending) {
 586                 dbus_pending_call_cancel(pending);
 587                 dbus_pending_call_unref(pending);
 588         }
 589
 590         if (message)
 591                 dbus_message_unref(message);
 592
 593         return -ENOMEM;
 594 }
 595
 596 static void query_name_list_pending_cb(DBusPendingCall *pending, void *userdata) {
 597         DBusMessage *reply;
 598         DBusError error;
 599         Manager *m = userdata;
 600
 601         assert(m);
 602
 603         dbus_error_init(&error);
 604
 605         assert_se(reply = dbus_pending_call_steal_reply(pending));
 606
 607         switch (dbus_message_get_type(reply)) {
 608
 609         case DBUS_MESSAGE_TYPE_ERROR:
 610
 611                 assert_se(dbus_set_error_from_message(&error, reply));
 612                 log_warning("ListNames() failed: %s", error.message);
 613                 break;
 614
 615         case DBUS_MESSAGE_TYPE_METHOD_RETURN: {
 616                 int r;
 617                 char **l;
 618
 619                 if ((r = bus_parse_strv(reply, &l)) < 0)
 620                         log_warning("Failed to parse ListNames() reply: %s", strerror(-r));
 621                 else {
 622                         char **t;
 623
 624                         STRV_FOREACH(t, l)
 625                                 /* This is a bit hacky, we say the
 626                                  * owner of the name is the name
 627                                  * itself, because we don't want the
 628                                  * extra traffic to figure out the
 629                                  * real owner. */
 630                                 manager_dispatch_bus_name_owner_changed(m, *t, NULL, *t);
 631
 632                         strv_free(l);
 633                 }
 634
 635                 break;
 636         }
 637
 638         default:
 639                 assert_not_reached("Invalid reply message");
 640         }
 641
 642         dbus_message_unref(reply);
 643         dbus_error_free(&error);
 644 }
 645
 646 static int query_name_list(Manager *m) {
 647         DBusMessage *message = NULL;
 648         DBusPendingCall *pending = NULL;
 649
 650         /* Asks for the currently installed bus names */
 651
 652         if (!(message = dbus_message_new_method_call(
 653                               DBUS_SERVICE_DBUS,
 654                               DBUS_PATH_DBUS,
 655                               DBUS_INTERFACE_DBUS,
 656                               "ListNames")))
 657                 goto oom;
 658
 659         if (!dbus_connection_send_with_reply(m->api_bus, message, &pending, -1))
 660                 goto oom;
 661
 662         if (!dbus_pending_call_set_notify(pending, query_name_list_pending_cb, m, NULL))
 663                 goto oom;
 664
 665         dbus_message_unref(message);
 666         dbus_pending_call_unref(pending);
 667
 668         /* We simple ask for the list and don't wait for it. Sooner or
 669          * later we'll get it. */
 670
 671         return 0;
 672
 673 oom:
 674         if (pending) {
 675                 dbus_pending_call_cancel(pending);
 676                 dbus_pending_call_unref(pending);
 677         }
 678
 679         if (message)
 680                 dbus_message_unref(message);
 681
 682         return -ENOMEM;
 683 }
 684
 685 static int bus_setup_loop(Manager *m, DBusConnection *bus) {
 686         assert(m);
 687         assert(bus);
 688
 689         dbus_connection_set_exit_on_disconnect(bus, FALSE);
 690
 691         if (!dbus_connection_set_watch_functions(bus, bus_add_watch, bus_remove_watch, bus_toggle_watch, m, NULL) ||
 692             !dbus_connection_set_timeout_functions(bus, bus_add_timeout, bus_remove_timeout, bus_toggle_timeout, m, NULL))
 693                 return -ENOMEM;
 694
 695         return 0;
 696 }
 697
 698 int bus_init_system(Manager *m) {
 699         DBusError error;
 700         char *id;
 701         int r;
 702
 703         assert(m);
 704
 705         dbus_error_init(&error);
 706
 707         if (m->system_bus)
 708                 return 0;
 709
 710         if (m->running_as != MANAGER_SESSION && m->api_bus)
 711                 m->system_bus = m->api_bus;
 712         else {
 713                 if (!(m->system_bus = dbus_bus_get_private(DBUS_BUS_SYSTEM, &error))) {
 714                         log_debug("Failed to get system D-Bus connection, retrying later: %s", error.message);
 715                         dbus_error_free(&error);
 716                         return 0;
 717                 }
 718
 719                 dbus_connection_set_dispatch_status_function(m->system_bus, system_bus_dispatch_status, m, NULL);
 720                 m->request_system_bus_dispatch = true;
 721
 722                 if ((r = bus_setup_loop(m, m->system_bus)) < 0) {
 723                         bus_done_system(m);
 724                         return r;
 725                 }
 726         }
 727
 728         if (!dbus_connection_add_filter(m->system_bus, system_bus_message_filter, m, NULL)) {
 729                 bus_done_system(m);
 730                 return -ENOMEM;
 731         }
 732
 733         dbus_bus_add_match(m->system_bus,
 734                            "type='signal',"
 735                            "interface='org.freedesktop.systemd1.Agent',"
 736                            "path='/org/freedesktop/systemd1/agent'",
 737                            &error);
 738
 739         if (dbus_error_is_set(&error)) {
 740                 log_error("Failed to register match: %s", error.message);
 741                 dbus_error_free(&error);
 742                 bus_done_system(m);
 743                 return -ENOMEM;
 744         }
 745
 746         log_debug("Successfully connected to system D-Bus bus %s as %s",
 747                   strnull((id = dbus_connection_get_server_id(m->system_bus))),
 748                   strnull(dbus_bus_get_unique_name(m->system_bus)));
 749         dbus_free(id);
 750
 751         return 0;
 752 }
 753
 754 int bus_init_api(Manager *m) {
 755         DBusError error;
 756         char *id;
 757         int r;
 758
 759         assert(m);
 760
 761         dbus_error_init(&error);
 762
 763         if (m->api_bus)
 764                 return 0;
 765
 766         if (m->name_data_slot < 0)
 767                 if (!dbus_pending_call_allocate_data_slot(&m->name_data_slot))
 768                         return -ENOMEM;
 769
 770         if (m->running_as != MANAGER_SESSION && m->system_bus)
 771                 m->api_bus = m->system_bus;
 772         else {
 773                 if (!(m->api_bus = dbus_bus_get_private(m->running_as == MANAGER_SESSION ? DBUS_BUS_SESSION : DBUS_BUS_SYSTEM, &error))) {
 774                         log_debug("Failed to get API D-Bus connection, retrying later: %s", error.message);
 775                         dbus_error_free(&error);
 776                         return 0;
 777                 }
 778
 779                 dbus_connection_set_dispatch_status_function(m->api_bus, api_bus_dispatch_status, m, NULL);
 780                 m->request_api_bus_dispatch = true;
 781
 782                 if ((r = bus_setup_loop(m, m->api_bus)) < 0) {
 783                         bus_done_api(m);
 784                         return r;
 785                 }
 786         }
 787
 788         if (!dbus_connection_register_object_path(m->api_bus, "/org/freedesktop/systemd1", &bus_manager_vtable, m) ||
 789             !dbus_connection_register_fallback(m->api_bus, "/org/freedesktop/systemd1/unit", &bus_unit_vtable, m) ||
 790             !dbus_connection_register_fallback(m->api_bus, "/org/freedesktop/systemd1/job", &bus_job_vtable, m) ||
 791             !dbus_connection_add_filter(m->api_bus, api_bus_message_filter, m, NULL)) {
 792                 bus_done_api(m);
 793                 return -ENOMEM;
 794         }
 795
 796         /* Get NameOwnerChange messages */
 797         dbus_bus_add_match(m->api_bus,
 798                            "type='signal',"
 799                            "sender='"DBUS_SERVICE_DBUS"',"
 800                            "interface='"DBUS_INTERFACE_DBUS"',"
 801                            "path='"DBUS_PATH_DBUS"'",
 802                            &error);
 803
 804         if (dbus_error_is_set(&error)) {
 805                 log_error("Failed to register match: %s", error.message);
 806                 dbus_error_free(&error);
 807                 bus_done_api(m);
 808                 return -ENOMEM;
 809         }
 810
 811         /* Get activation requests */
 812         dbus_bus_add_match(m->api_bus,
 813                            "type='signal',"
 814                            "sender='"DBUS_SERVICE_DBUS"',"
 815                            "interface='org.freedesktop.systemd1.Activator',"
 816                            "path='"DBUS_PATH_DBUS"'",
 817                            &error);
 818
 819         if (dbus_error_is_set(&error)) {
 820                 log_error("Failed to register match: %s", error.message);
 821                 dbus_error_free(&error);
 822                 bus_done_api(m);
 823                 return -ENOMEM;
 824         }
 825
 826         if ((r = request_name(m)) < 0) {
 827                 bus_done_api(m);
 828                 return r;
 829         }
 830
 831         if ((r = query_name_list(m)) < 0) {
 832                 bus_done_api(m);
 833                 return r;
 834         }
 835
 836         log_debug("Successfully connected to API D-Bus bus %s as %s",
 837                   strnull((id = dbus_connection_get_server_id(m->api_bus))),
 838                   strnull(dbus_bus_get_unique_name(m->api_bus)));
 839         dbus_free(id);
 840
 841         if (!m->subscribed)
 842                 if (!(m->subscribed = set_new(string_hash_func, string_compare_func)))
 843                         return -ENOMEM;
 844
 845         return 0;
 846 }
 847
 848 void bus_done_api(Manager *m) {
 849         assert(m);
 850
 851         if (m->api_bus) {
 852                 if (m->system_bus == m->api_bus)
 853                         m->system_bus = NULL;
 854
 855                 dbus_connection_set_dispatch_status_function(m->api_bus, NULL, NULL, NULL);
 856                 dbus_connection_flush(m->api_bus);
 857                 dbus_connection_close(m->api_bus);
 858                 dbus_connection_unref(m->api_bus);
 859                 m->api_bus = NULL;
 860         }
 861
 862         if (m->subscribed) {
 863                 char *c;
 864
 865                 while ((c = set_steal_first(m->subscribed)))
 866                         free(c);
 867
 868                 set_free(m->subscribed);
 869                 m->subscribed = NULL;
 870         }
 871
 872        if (m->name_data_slot >= 0)
 873                dbus_pending_call_free_data_slot(&m->name_data_slot);
 874
 875        if (m->queued_message) {
 876                dbus_message_unref(m->queued_message);
 877                m->queued_message = NULL;
 878        }
 879 }
 880
 881 void bus_done_system(Manager *m) {
 882         assert(m);
 883
 884         if (m->system_bus == m->api_bus)
 885                 bus_done_api(m);
 886
 887         if (m->system_bus) {
 888                 dbus_connection_set_dispatch_status_function(m->system_bus, NULL, NULL, NULL);
 889                 dbus_connection_flush(m->system_bus);
 890                 dbus_connection_close(m->system_bus);
 891                 dbus_connection_unref(m->system_bus);
 892                 m->system_bus = NULL;
 893         }
 894 }
 895
 896 static void query_pid_pending_cb(DBusPendingCall *pending, void *userdata) {
 897         Manager *m = userdata;
 898         DBusMessage *reply;
 899         DBusError error;
 900         const char *name;
 901
 902         dbus_error_init(&error);
 903
 904         assert_se(name = dbus_pending_call_get_data(pending, m->name_data_slot));
 905         assert_se(reply = dbus_pending_call_steal_reply(pending));
 906
 907         switch (dbus_message_get_type(reply)) {
 908
 909         case DBUS_MESSAGE_TYPE_ERROR:
 910
 911                 assert_se(dbus_set_error_from_message(&error, reply));
 912                 log_warning("GetConnectionUnixProcessID() failed: %s", error.message);
 913                 break;
 914
 915         case DBUS_MESSAGE_TYPE_METHOD_RETURN: {
 916                 uint32_t r;
 917
 918                 if (!dbus_message_get_args(reply,
 919                                            &error,
 920                                            DBUS_TYPE_UINT32, &r,
 921                                            DBUS_TYPE_INVALID)) {
 922                         log_error("Failed to parse GetConnectionUnixProcessID() reply: %s", error.message);
 923                         break;
 924                 }
 925
 926                 manager_dispatch_bus_query_pid_done(m, name, (pid_t) r);
 927                 break;
 928         }
 929
 930         default:
 931                 assert_not_reached("Invalid reply message");
 932         }
 933
 934         dbus_message_unref(reply);
 935         dbus_error_free(&error);
 936 }
 937
 938 int bus_query_pid(Manager *m, const char *name) {
 939         DBusMessage *message = NULL;
 940         DBusPendingCall *pending = NULL;
 941         char *n = NULL;
 942
 943         assert(m);
 944         assert(name);
 945
 946         if (!(message = dbus_message_new_method_call(
 947                               DBUS_SERVICE_DBUS,
 948                               DBUS_PATH_DBUS,
 949                               DBUS_INTERFACE_DBUS,
 950                               "GetConnectionUnixProcessID")))
 951                 goto oom;
 952
 953         if (!(dbus_message_append_args(
 954                               message,
 955                               DBUS_TYPE_STRING, &name,
 956                               DBUS_TYPE_INVALID)))
 957                 goto oom;
 958
 959         if (!dbus_connection_send_with_reply(m->api_bus, message, &pending, -1))
 960                 goto oom;
 961
 962         if (!(n = strdup(name)))
 963                 goto oom;
 964
 965         if (!dbus_pending_call_set_data(pending, m->name_data_slot, n, free))
 966                 goto oom;
 967
 968         n = NULL;
 969
 970         if (!dbus_pending_call_set_notify(pending, query_pid_pending_cb, m, NULL))
 971                 goto oom;
 972
 973         dbus_message_unref(message);
 974         dbus_pending_call_unref(pending);
 975
 976         return 0;
 977
 978 oom:
 979         free(n);
 980
 981         if (pending) {
 982                 dbus_pending_call_cancel(pending);
 983                 dbus_pending_call_unref(pending);
 984         }
 985
 986         if (message)
 987                 dbus_message_unref(message);
 988
 989         return -ENOMEM;
 990 }
 991
 992 DBusHandlerResult bus_default_message_handler(Manager *m, DBusMessage *message, const char*introspection, const BusProperty *properties) {
 993         DBusError error;
 994         DBusMessage *reply = NULL;
 995         int r;
 996
 997         assert(m);
 998         assert(message);
 999
1000         dbus_error_init(&error);
1001
1002         if (dbus_message_is_method_call(message, "org.freedesktop.DBus.Introspectable", "Introspect") && introspection) {
1003
1004                 if (!(reply = dbus_message_new_method_return(message)))
1005                         goto oom;
1006
1007                 if (!dbus_message_append_args(reply, DBUS_TYPE_STRING, &introspection, DBUS_TYPE_INVALID))
1008                         goto oom;
1009
1010         } else if (dbus_message_is_method_call(message, "org.freedesktop.DBus.Properties", "Get") && properties) {
1011                 const char *interface, *property;
1012                 const BusProperty *p;
1013
1014                 if (!dbus_message_get_args(
1015                             message,
1016                             &error,
1017                             DBUS_TYPE_STRING, &interface,
1018                             DBUS_TYPE_STRING, &property,
1019                             DBUS_TYPE_INVALID))
1020                         return bus_send_error_reply(m, message, &error, -EINVAL);
1021
1022                 for (p = properties; p->property; p++)
1023                         if (streq(p->interface, interface) && streq(p->property, property))
1024                                 break;
1025
1026                 if (p->property) {
1027                         DBusMessageIter iter, sub;
1028
1029                         if (!(reply = dbus_message_new_method_return(message)))
1030                                 goto oom;
1031
1032                         dbus_message_iter_init_append(reply, &iter);
1033
1034                         if (!dbus_message_iter_open_container(&iter, DBUS_TYPE_VARIANT, p->signature, &sub))
1035                                 goto oom;
1036
1037                         if ((r = p->append(m, &sub, property, (void*) p->data)) < 0) {
1038
1039                                 if (r == -ENOMEM)
1040                                         goto oom;
1041
1042                                 dbus_message_unref(reply);
1043                                 return bus_send_error_reply(m, message, NULL, r);
1044                         }
1045
1046                         if (!dbus_message_iter_close_container(&iter, &sub))
1047                                 goto oom;
1048                 }
1049         } else if (dbus_message_is_method_call(message, "org.freedesktop.DBus.Properties", "GetAll") && properties) {
1050                 const char *interface;
1051                 const BusProperty *p;
1052                 DBusMessageIter iter, sub, sub2, sub3;
1053                 bool any = false;
1054
1055                 if (!dbus_message_get_args(
1056                             message,
1057                             &error,
1058                             DBUS_TYPE_STRING, &interface,
1059                             DBUS_TYPE_INVALID))
1060                         return bus_send_error_reply(m, message, &error, -EINVAL);
1061
1062                 if (!(reply = dbus_message_new_method_return(message)))
1063                         goto oom;
1064
1065                 dbus_message_iter_init_append(reply, &iter);
1066
1067                 if (!dbus_message_iter_open_container(&iter, DBUS_TYPE_ARRAY, "{sv}", &sub))
1068                         goto oom;
1069
1070                 for (p = properties; p->property; p++) {
1071                         if (!streq(p->interface, interface))
1072                                 continue;
1073
1074                         if (!dbus_message_iter_open_container(&sub, DBUS_TYPE_DICT_ENTRY, NULL, &sub2) ||
1075                             !dbus_message_iter_append_basic(&sub2, DBUS_TYPE_STRING, &p->property) ||
1076                             !dbus_message_iter_open_container(&sub2, DBUS_TYPE_VARIANT, p->signature, &sub3))
1077                                 goto oom;
1078
1079                         if ((r = p->append(m, &sub3, p->property, (void*) p->data)) < 0) {
1080
1081                                 if (r == -ENOMEM)
1082                                         goto oom;
1083
1084                                 dbus_message_unref(reply);
1085                                 return bus_send_error_reply(m, message, NULL, r);
1086                         }
1087
1088                         if (!dbus_message_iter_close_container(&sub2, &sub3) ||
1089                             !dbus_message_iter_close_container(&sub, &sub2))
1090                                 goto oom;
1091
1092                         any = true;
1093                 }
1094
1095                 if (!dbus_message_iter_close_container(&iter, &sub))
1096                         goto oom;
1097         }
1098
1099         if (reply) {
1100                 if (!dbus_connection_send(m->api_bus, reply, NULL))
1101                         goto oom;
1102
1103                 dbus_message_unref(reply);
1104                 return DBUS_HANDLER_RESULT_HANDLED;
1105         }
1106
1107         return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
1108
1109 oom:
1110         if (reply)
1111                 dbus_message_unref(reply);
1112
1113         dbus_error_free(&error);
1114
1115         return DBUS_HANDLER_RESULT_NEED_MEMORY;
1116 }
1117
1118 static const char *error_to_dbus(int error) {
1119
1120         switch(error) {
1121
1122         case -EINVAL:
1123                 return DBUS_ERROR_INVALID_ARGS;
1124
1125         case -ENOMEM:
1126                 return DBUS_ERROR_NO_MEMORY;
1127
1128         case -EPERM:
1129         case -EACCES:
1130                 return DBUS_ERROR_ACCESS_DENIED;
1131
1132         case -ESRCH:
1133                 return DBUS_ERROR_UNIX_PROCESS_ID_UNKNOWN;
1134
1135         case -ENOENT:
1136                 return DBUS_ERROR_FILE_NOT_FOUND;
1137
1138         case -EEXIST:
1139                 return DBUS_ERROR_FILE_EXISTS;
1140
1141         case -ETIMEDOUT:
1142                 return DBUS_ERROR_TIMEOUT;
1143
1144         case -EIO:
1145                 return DBUS_ERROR_IO_ERROR;
1146
1147         case -ENETRESET:
1148         case -ECONNABORTED:
1149         case -ECONNRESET:
1150                 return DBUS_ERROR_DISCONNECTED;
1151         }
1152
1153         return DBUS_ERROR_FAILED;
1154 }
1155
1156 DBusHandlerResult bus_send_error_reply(Manager *m, DBusMessage *message, DBusError *bus_error, int error) {
1157         DBusMessage *reply = NULL;
1158         const char *name, *text;
1159
1160         if (bus_error && dbus_error_is_set(bus_error)) {
1161                 name = bus_error->name;
1162                 text = bus_error->message;
1163         } else {
1164                 name = error_to_dbus(error);
1165                 text = strerror(-error);
1166         }
1167
1168         if (!(reply = dbus_message_new_error(message, name, text)))
1169                 goto oom;
1170
1171         if (!dbus_connection_send(m->api_bus, reply, NULL))
1172                 goto oom;
1173
1174         dbus_message_unref(reply);
1175
1176         if (bus_error)
1177                 dbus_error_free(bus_error);
1178
1179         return DBUS_HANDLER_RESULT_HANDLED;
1180
1181 oom:
1182         if (reply)
1183                 dbus_message_unref(reply);
1184
1185         if (bus_error)
1186                 dbus_error_free(bus_error);
1187
1188         return DBUS_HANDLER_RESULT_NEED_MEMORY;
1189 }
1190
1191 int bus_property_append_string(Manager *m, DBusMessageIter *i, const char *property, void *data) {
1192         const char *t = data;
1193
1194         assert(m);
1195         assert(i);
1196         assert(property);
1197
1198         if (!t)
1199                 t = "";
1200
1201         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_STRING, &t))
1202                 return -ENOMEM;
1203
1204         return 0;
1205 }
1206
1207 int bus_property_append_strv(Manager *m, DBusMessageIter *i, const char *property, void *data) {
1208         DBusMessageIter sub;
1209         char **t = data;
1210
1211         assert(m);
1212         assert(i);
1213         assert(property);
1214
1215         if (!dbus_message_iter_open_container(i, DBUS_TYPE_ARRAY, "s", &sub))
1216                 return -ENOMEM;
1217
1218         STRV_FOREACH(t, t)
1219                 if (!dbus_message_iter_append_basic(&sub, DBUS_TYPE_STRING, t))
1220                         return -ENOMEM;
1221
1222         if (!dbus_message_iter_close_container(i, &sub))
1223                 return -ENOMEM;
1224
1225         return 0;
1226 }
1227
1228 int bus_property_append_bool(Manager *m, DBusMessageIter *i, const char *property, void *data) {
1229         bool *b = data;
1230         dbus_bool_t db;
1231
1232         assert(m);
1233         assert(i);
1234         assert(property);
1235         assert(b);
1236
1237         db = *b;
1238
1239         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_BOOLEAN, &db))
1240                 return -ENOMEM;
1241
1242         return 0;
1243 }
1244
1245 int bus_property_append_uint64(Manager *m, DBusMessageIter *i, const char *property, void *data) {
1246         assert(m);
1247         assert(i);
1248         assert(property);
1249         assert(data);
1250
1251         /* Let's ensure that pid_t is actually 64bit, and hence this
1252          * function can be used for usec_t */
1253         assert_cc(sizeof(uint64_t) == sizeof(usec_t));
1254
1255         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_UINT64, data))
1256                 return -ENOMEM;
1257
1258         return 0;
1259 }
1260
1261 int bus_property_append_uint32(Manager *m, DBusMessageIter *i, const char *property, void *data) {
1262         assert(m);
1263         assert(i);
1264         assert(property);
1265         assert(data);
1266
1267         /* Let's ensure that pid_t and mode_t is actually 32bit, and
1268          * hence this function can be used for pid_t/mode_t */
1269         assert_cc(sizeof(uint32_t) == sizeof(pid_t));
1270         assert_cc(sizeof(uint32_t) == sizeof(mode_t));
1271         assert_cc(sizeof(uint32_t) == sizeof(unsigned));
1272
1273         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_UINT32, data))
1274                 return -ENOMEM;
1275
1276         return 0;
1277 }
1278
1279 int bus_property_append_int32(Manager *m, DBusMessageIter *i, const char *property, void *data) {
1280         assert(m);
1281         assert(i);
1282         assert(property);
1283         assert(data);
1284
1285         assert_cc(sizeof(int32_t) == sizeof(int));
1286
1287         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_INT32, data))
1288                 return -ENOMEM;
1289
1290         return 0;
1291 }
1292
1293 int bus_parse_strv(DBusMessage *m, char ***_l) {
1294         DBusMessageIter iter, sub;
1295         unsigned n = 0, i = 0;
1296         char **l;
1297
1298         assert(m);
1299         assert(_l);
1300
1301         if (!dbus_message_iter_init(m, &iter) ||
1302             dbus_message_iter_get_arg_type(&iter) != DBUS_TYPE_ARRAY ||
1303             dbus_message_iter_get_element_type(&iter) != DBUS_TYPE_STRING)
1304             return -EINVAL;
1305
1306         dbus_message_iter_recurse(&iter, &sub);
1307
1308         while (dbus_message_iter_get_arg_type(&sub) != DBUS_TYPE_INVALID) {
1309                 n++;
1310                 dbus_message_iter_next(&sub);
1311         }
1312
1313         if (!(l = new(char*, n+1)))
1314                 return -ENOMEM;
1315
1316         assert_se(dbus_message_iter_init(m, &iter));
1317         dbus_message_iter_recurse(&iter, &sub);
1318
1319         while (dbus_message_iter_get_arg_type(&sub) != DBUS_TYPE_INVALID) {
1320                 const char *s;
1321
1322                 assert_se(dbus_message_iter_get_arg_type(&sub) == DBUS_TYPE_STRING);
1323                 dbus_message_iter_get_basic(&sub, &s);
1324
1325                 if (!(l[i++] = strdup(s))) {
1326                         strv_free(l);
1327                         return -ENOMEM;
1328                 }
1329
1330                 dbus_message_iter_next(&sub);
1331         }
1332
1333         assert(i == n);
1334         l[i] = NULL;
1335
1336         if (_l)
1337                 *_l = l;
1338
1339         return 0;
1340 }