src/dbus-common.c

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   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 <assert.h>
  23 #include <sys/socket.h>
  24 #include <errno.h>
  25 #include <unistd.h>
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28 #include <dbus/dbus.h>
  29 #include <string.h>
  30 #include <sys/epoll.h>
  31
  32 #include "log.h"
  33 #include "dbus-common.h"
  34 #include "util.h"
  35 #include "def.h"
  36 #include "strv.h"
  37
  38 int bus_check_peercred(DBusConnection *c) {
  39         int fd;
  40         struct ucred ucred;
  41         socklen_t l;
  42
  43         assert(c);
  44
  45         assert_se(dbus_connection_get_unix_fd(c, &fd));
  46
  47         l = sizeof(struct ucred);
  48         if (getsockopt(fd, SOL_SOCKET, SO_PEERCRED, &ucred, &l) < 0) {
  49                 log_error("SO_PEERCRED failed: %m");
  50                 return -errno;
  51         }
  52
  53         if (l != sizeof(struct ucred)) {
  54                 log_error("SO_PEERCRED returned wrong size.");
  55                 return -E2BIG;
  56         }
  57
  58         if (ucred.uid != 0 && ucred.uid != geteuid())
  59                 return -EPERM;
  60
  61         return 1;
  62 }
  63
  64 static int sync_auth(DBusConnection *bus, DBusError *error) {
  65         usec_t begin, tstamp;
  66
  67         assert(bus);
  68
  69         /* This complexity should probably move into D-Bus itself:
  70          *
  71          * https://bugs.freedesktop.org/show_bug.cgi?id=35189 */
  72
  73         begin = tstamp = now(CLOCK_MONOTONIC);
  74         for (;;) {
  75
  76                 if (tstamp > begin + DEFAULT_TIMEOUT_USEC)
  77                         break;
  78
  79                 if (dbus_connection_get_is_authenticated(bus))
  80                         break;
  81
  82                 if (!dbus_connection_read_write_dispatch(bus, ((begin + DEFAULT_TIMEOUT_USEC - tstamp) + USEC_PER_MSEC - 1) / USEC_PER_MSEC))
  83                         break;
  84
  85                 tstamp = now(CLOCK_MONOTONIC);
  86         }
  87
  88         if (!dbus_connection_get_is_connected(bus)) {
  89                 dbus_set_error_const(error, DBUS_ERROR_NO_SERVER, "Connection terminated during authentication.");
  90                 return -ECONNREFUSED;
  91         }
  92
  93         if (!dbus_connection_get_is_authenticated(bus)) {
  94                 dbus_set_error_const(error, DBUS_ERROR_TIMEOUT, "Failed to authenticate in time.");
  95                 return -EACCES;
  96         }
  97
  98         return 0;
  99 }
 100
 101 int bus_connect(DBusBusType t, DBusConnection **_bus, bool *_private, DBusError *error) {
 102         DBusConnection *bus = NULL;
 103         int r;
 104         bool private = true;
 105
 106         assert(_bus);
 107
 108         if (geteuid() == 0 && t == DBUS_BUS_SYSTEM) {
 109                 /* If we are root, then let's talk directly to the
 110                  * system instance, instead of going via the bus */
 111
 112                 bus = dbus_connection_open_private("unix:path=/run/systemd/private", error);
 113                 if (!bus)
 114                         return -EIO;
 115
 116         } else {
 117                 if (t == DBUS_BUS_SESSION) {
 118                         const char *e;
 119
 120                         /* If we are supposed to talk to the instance,
 121                          * try via XDG_RUNTIME_DIR first, then
 122                          * fallback to normal bus access */
 123
 124                         e = getenv("XDG_RUNTIME_DIR");
 125                         if (e) {
 126                                 char *p;
 127
 128                                 if (asprintf(&p, "unix:path=%s/systemd/private", e) < 0)
 129                                         return -ENOMEM;
 130
 131                                 bus = dbus_connection_open_private(p, NULL);
 132                                 free(p);
 133                         }
 134                 }
 135
 136                 if (!bus) {
 137                         bus = dbus_bus_get_private(t, error);
 138                         if (!bus)
 139                                 return -EIO;
 140
 141                         private = false;
 142                 }
 143         }
 144
 145         dbus_connection_set_exit_on_disconnect(bus, FALSE);
 146
 147         if (private) {
 148                 if (bus_check_peercred(bus) < 0) {
 149                         dbus_connection_close(bus);
 150                         dbus_connection_unref(bus);
 151
 152                         dbus_set_error_const(error, DBUS_ERROR_ACCESS_DENIED, "Failed to verify owner of bus.");
 153                         return -EACCES;
 154                 }
 155         }
 156
 157         r = sync_auth(bus, error);
 158         if (r < 0) {
 159                 dbus_connection_close(bus);
 160                 dbus_connection_unref(bus);
 161                 return r;
 162         }
 163
 164         if (_private)
 165                 *_private = private;
 166
 167         *_bus = bus;
 168         return 0;
 169 }
 170
 171 int bus_connect_system_ssh(const char *user, const char *host, DBusConnection **_bus, DBusError *error) {
 172         DBusConnection *bus;
 173         char *p = NULL;
 174         int r;
 175
 176         assert(_bus);
 177         assert(user || host);
 178
 179         if (user && host)
 180                 asprintf(&p, "unixexec:path=ssh,argv1=-xT,argv2=%s@%s,argv3=systemd-stdio-bridge", user, host);
 181         else if (user)
 182                 asprintf(&p, "unixexec:path=ssh,argv1=-xT,argv2=%s@localhost,argv3=systemd-stdio-bridge", user);
 183         else if (host)
 184                 asprintf(&p, "unixexec:path=ssh,argv1=-xT,argv2=%s,argv3=systemd-stdio-bridge", host);
 185
 186         if (!p) {
 187                 dbus_set_error_const(error, DBUS_ERROR_NO_MEMORY, NULL);
 188                 return -ENOMEM;
 189         }
 190
 191         bus = dbus_connection_open_private(p, error);
 192         free(p);
 193
 194         if (!bus)
 195                 return -EIO;
 196
 197         dbus_connection_set_exit_on_disconnect(bus, FALSE);
 198
 199         if ((r = sync_auth(bus, error)) < 0) {
 200                 dbus_connection_close(bus);
 201                 dbus_connection_unref(bus);
 202                 return r;
 203         }
 204
 205         if (!dbus_bus_register(bus, error)) {
 206                 dbus_connection_close(bus);
 207                 dbus_connection_unref(bus);
 208                 return r;
 209         }
 210
 211         *_bus = bus;
 212         return 0;
 213 }
 214
 215 int bus_connect_system_polkit(DBusConnection **_bus, DBusError *error) {
 216         DBusConnection *bus;
 217         int r;
 218
 219         assert(_bus);
 220
 221         /* Don't bother with PolicyKit if we are root */
 222         if (geteuid() == 0)
 223                 return bus_connect(DBUS_BUS_SYSTEM, _bus, NULL, error);
 224
 225         bus = dbus_connection_open_private("unixexec:path=pkexec,argv1=" SYSTEMD_STDIO_BRIDGE_BINARY_PATH, error);
 226         if (!bus)
 227                 return -EIO;
 228
 229         dbus_connection_set_exit_on_disconnect(bus, FALSE);
 230
 231         if ((r = sync_auth(bus, error)) < 0) {
 232                 dbus_connection_close(bus);
 233                 dbus_connection_unref(bus);
 234                 return r;
 235         }
 236
 237         if (!dbus_bus_register(bus, error)) {
 238                 dbus_connection_close(bus);
 239                 dbus_connection_unref(bus);
 240                 return r;
 241         }
 242
 243         *_bus = bus;
 244         return 0;
 245 }
 246
 247 const char *bus_error_message(const DBusError *error) {
 248         assert(error);
 249
 250         /* Sometimes the D-Bus server is a little bit too verbose with
 251          * its error messages, so let's override them here */
 252         if (dbus_error_has_name(error, DBUS_ERROR_ACCESS_DENIED))
 253                 return "Access denied";
 254
 255         return error->message;
 256 }
 257
 258 DBusHandlerResult bus_default_message_handler(
 259                 DBusConnection *c,
 260                 DBusMessage *message,
 261                 const char *introspection,
 262                 const char *interfaces,
 263                 const BusBoundProperties *bound_properties) {
 264
 265         DBusError error;
 266         DBusMessage *reply = NULL;
 267         int r;
 268
 269         assert(c);
 270         assert(message);
 271
 272         dbus_error_init(&error);
 273
 274         if (dbus_message_is_method_call(message, "org.freedesktop.DBus.Introspectable", "Introspect") && introspection) {
 275
 276                 if (!(reply = dbus_message_new_method_return(message)))
 277                         goto oom;
 278
 279                 if (!dbus_message_append_args(reply, DBUS_TYPE_STRING, &introspection, DBUS_TYPE_INVALID))
 280                         goto oom;
 281
 282         } else if (dbus_message_is_method_call(message, "org.freedesktop.DBus.Properties", "Get") && bound_properties) {
 283                 const char *interface, *property;
 284                 const BusBoundProperties *bp;
 285                 const BusProperty *p;
 286                 void *data;
 287                 DBusMessageIter iter, sub;
 288
 289                 if (!dbus_message_get_args(
 290                             message,
 291                             &error,
 292                             DBUS_TYPE_STRING, &interface,
 293                             DBUS_TYPE_STRING, &property,
 294                             DBUS_TYPE_INVALID))
 295                         return bus_send_error_reply(c, message, &error, -EINVAL);
 296
 297                 for (bp = bound_properties; bp->interface; bp++) {
 298                         if (!streq(bp->interface, interface))
 299                                 continue;
 300
 301                         for (p = bp->properties; p->property; p++)
 302                                 if (streq(p->property, property))
 303                                         goto get_prop;
 304                 }
 305
 306                 /* no match */
 307                 if (!nulstr_contains(interfaces, interface))
 308                         dbus_set_error_const(&error, DBUS_ERROR_UNKNOWN_INTERFACE, "Unknown interface");
 309                 else
 310                         dbus_set_error_const(&error, DBUS_ERROR_UNKNOWN_PROPERTY, "Unknown property");
 311
 312                 return bus_send_error_reply(c, message, &error, -EINVAL);
 313
 314 get_prop:
 315                 reply = dbus_message_new_method_return(message);
 316                 if (!reply)
 317                         goto oom;
 318
 319                 dbus_message_iter_init_append(reply, &iter);
 320
 321                 if (!dbus_message_iter_open_container(&iter, DBUS_TYPE_VARIANT, p->signature, &sub))
 322                         goto oom;
 323
 324                 data = (char*)bp->base + p->offset;
 325                 if (p->indirect)
 326                         data = *(void**)data;
 327                 r = p->append(&sub, property, data);
 328                 if (r < 0) {
 329                         if (r == -ENOMEM)
 330                                 goto oom;
 331
 332                         dbus_message_unref(reply);
 333                         return bus_send_error_reply(c, message, NULL, r);
 334                 }
 335
 336                 if (!dbus_message_iter_close_container(&iter, &sub))
 337                         goto oom;
 338
 339         } else if (dbus_message_is_method_call(message, "org.freedesktop.DBus.Properties", "GetAll") && bound_properties) {
 340                 const char *interface;
 341                 const BusBoundProperties *bp;
 342                 const BusProperty *p;
 343                 DBusMessageIter iter, sub, sub2, sub3;
 344
 345                 if (!dbus_message_get_args(
 346                             message,
 347                             &error,
 348                             DBUS_TYPE_STRING, &interface,
 349                             DBUS_TYPE_INVALID))
 350                         return bus_send_error_reply(c, message, &error, -EINVAL);
 351
 352                 if (interface[0] && !nulstr_contains(interfaces, interface)) {
 353                         dbus_set_error_const(&error, DBUS_ERROR_UNKNOWN_INTERFACE, "Unknown interface");
 354                         return bus_send_error_reply(c, message, &error, -EINVAL);
 355                 }
 356
 357                 if (!(reply = dbus_message_new_method_return(message)))
 358                         goto oom;
 359
 360                 dbus_message_iter_init_append(reply, &iter);
 361
 362                 if (!dbus_message_iter_open_container(&iter, DBUS_TYPE_ARRAY, "{sv}", &sub))
 363                         goto oom;
 364
 365                 for (bp = bound_properties; bp->interface; bp++) {
 366                         if (interface[0] && !streq(bp->interface, interface))
 367                                 continue;
 368
 369                         for (p = bp->properties; p->property; p++) {
 370                                 void *data;
 371
 372                                 if (!dbus_message_iter_open_container(&sub, DBUS_TYPE_DICT_ENTRY, NULL, &sub2) ||
 373                                     !dbus_message_iter_append_basic(&sub2, DBUS_TYPE_STRING, &p->property) ||
 374                                     !dbus_message_iter_open_container(&sub2, DBUS_TYPE_VARIANT, p->signature, &sub3))
 375                                         goto oom;
 376
 377                                 data = (char*)bp->base + p->offset;
 378                                 if (p->indirect)
 379                                         data = *(void**)data;
 380                                 r = p->append(&sub3, p->property, data);
 381                                 if (r < 0) {
 382                                         if (r == -ENOMEM)
 383                                                 goto oom;
 384
 385                                         dbus_message_unref(reply);
 386                                         return bus_send_error_reply(c, message, NULL, r);
 387                                 }
 388
 389                                 if (!dbus_message_iter_close_container(&sub2, &sub3) ||
 390                                     !dbus_message_iter_close_container(&sub, &sub2))
 391                                         goto oom;
 392                         }
 393                 }
 394
 395                 if (!dbus_message_iter_close_container(&iter, &sub))
 396                         goto oom;
 397
 398         } else if (dbus_message_is_method_call(message, "org.freedesktop.DBus.Properties", "Set") && bound_properties) {
 399                 const char *interface, *property;
 400                 DBusMessageIter iter;
 401                 const BusBoundProperties *bp;
 402                 const BusProperty *p;
 403                 DBusMessageIter sub;
 404                 char *sig;
 405                 void *data;
 406
 407                 if (!dbus_message_iter_init(message, &iter) ||
 408                     dbus_message_iter_get_arg_type(&iter) != DBUS_TYPE_STRING)
 409                         return bus_send_error_reply(c, message, NULL, -EINVAL);
 410
 411                 dbus_message_iter_get_basic(&iter, &interface);
 412
 413                 if (!dbus_message_iter_next(&iter) ||
 414                     dbus_message_iter_get_arg_type(&iter) != DBUS_TYPE_STRING)
 415                         return bus_send_error_reply(c, message, NULL, -EINVAL);
 416
 417                 dbus_message_iter_get_basic(&iter, &property);
 418
 419                 if (!dbus_message_iter_next(&iter) ||
 420                     dbus_message_iter_get_arg_type(&iter) != DBUS_TYPE_VARIANT ||
 421                     dbus_message_iter_has_next(&iter))
 422                         return bus_send_error_reply(c, message, NULL, -EINVAL);
 423
 424                 for (bp = bound_properties; bp->interface; bp++) {
 425                         if (!streq(bp->interface, interface))
 426                                 continue;
 427
 428                         for (p = bp->properties; p->property; p++)
 429                                 if (streq(p->property, property))
 430                                         goto set_prop;
 431                 }
 432
 433                 /* no match */
 434                 if (!nulstr_contains(interfaces, interface))
 435                         dbus_set_error_const(&error, DBUS_ERROR_UNKNOWN_INTERFACE, "Unknown interface");
 436                 else
 437                         dbus_set_error_const(&error, DBUS_ERROR_UNKNOWN_PROPERTY, "Unknown property");
 438
 439                 return bus_send_error_reply(c, message, &error, -EINVAL);
 440
 441 set_prop:
 442                 if (!p->set) {
 443                         dbus_set_error_const(&error, DBUS_ERROR_PROPERTY_READ_ONLY, "Property read-only");
 444                         return bus_send_error_reply(c, message, &error, -EINVAL);
 445                 }
 446
 447                 dbus_message_iter_recurse(&iter, &sub);
 448
 449                 sig = dbus_message_iter_get_signature(&sub);
 450                 if (!sig)
 451                         goto oom;
 452
 453                 if (!streq(sig, p->signature)) {
 454                         dbus_free(sig);
 455                         return bus_send_error_reply(c, message, NULL, -EINVAL);
 456                 }
 457
 458                 dbus_free(sig);
 459
 460                 data = (char*)bp->base + p->offset;
 461                 if (p->indirect)
 462                         data = *(void**)data;
 463                 r = p->set(&sub, property, data);
 464                 if (r < 0) {
 465                         if (r == -ENOMEM)
 466                                 goto oom;
 467                         return bus_send_error_reply(c, message, NULL, r);
 468                 }
 469
 470                 reply = dbus_message_new_method_return(message);
 471                 if (!reply)
 472                         goto oom;
 473         } else {
 474                 const char *interface = dbus_message_get_interface(message);
 475
 476                 if (!interface || !nulstr_contains(interfaces, interface)) {
 477                         dbus_set_error_const(&error, DBUS_ERROR_UNKNOWN_INTERFACE, "Unknown interface");
 478                         return bus_send_error_reply(c, message, &error, -EINVAL);
 479                 }
 480         }
 481
 482         if (reply) {
 483                 if (!dbus_connection_send(c, reply, NULL))
 484                         goto oom;
 485
 486                 dbus_message_unref(reply);
 487                 return DBUS_HANDLER_RESULT_HANDLED;
 488         }
 489
 490         return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 491
 492 oom:
 493         if (reply)
 494                 dbus_message_unref(reply);
 495
 496         dbus_error_free(&error);
 497
 498         return DBUS_HANDLER_RESULT_NEED_MEMORY;
 499 }
 500
 501 int bus_property_append_string(DBusMessageIter *i, const char *property, void *data) {
 502         const char *t = data;
 503
 504         assert(i);
 505         assert(property);
 506
 507         if (!t)
 508                 t = "";
 509
 510         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_STRING, &t))
 511                 return -ENOMEM;
 512
 513         return 0;
 514 }
 515
 516 int bus_property_append_strv(DBusMessageIter *i, const char *property, void *data) {
 517         char **t = data;
 518
 519         assert(i);
 520         assert(property);
 521
 522         return bus_append_strv_iter(i, t);
 523 }
 524
 525 int bus_property_append_bool(DBusMessageIter *i, const char *property, void *data) {
 526         bool *b = data;
 527         dbus_bool_t db;
 528
 529         assert(i);
 530         assert(property);
 531         assert(b);
 532
 533         db = *b;
 534
 535         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_BOOLEAN, &db))
 536                 return -ENOMEM;
 537
 538         return 0;
 539 }
 540
 541 int bus_property_append_tristate_false(DBusMessageIter *i, const char *property, void *data) {
 542         int *b = data;
 543         dbus_bool_t db;
 544
 545         assert(i);
 546         assert(property);
 547         assert(b);
 548
 549         db = *b > 0;
 550
 551         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_BOOLEAN, &db))
 552                 return -ENOMEM;
 553
 554         return 0;
 555 }
 556
 557 int bus_property_append_uint64(DBusMessageIter *i, const char *property, void *data) {
 558         assert(i);
 559         assert(property);
 560         assert(data);
 561
 562         /* Let's ensure that usec_t is actually 64bit, and hence this
 563          * function can be used for usec_t */
 564         assert_cc(sizeof(uint64_t) == sizeof(usec_t));
 565
 566         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_UINT64, data))
 567                 return -ENOMEM;
 568
 569         return 0;
 570 }
 571
 572 int bus_property_append_uint32(DBusMessageIter *i, const char *property, void *data) {
 573         assert(i);
 574         assert(property);
 575         assert(data);
 576
 577         /* Let's ensure that pid_t, mode_t, uid_t, gid_t are actually
 578          * 32bit, and hence this function can be used for
 579          * pid_t/mode_t/uid_t/gid_t */
 580         assert_cc(sizeof(uint32_t) == sizeof(pid_t));
 581         assert_cc(sizeof(uint32_t) == sizeof(mode_t));
 582         assert_cc(sizeof(uint32_t) == sizeof(unsigned));
 583         assert_cc(sizeof(uint32_t) == sizeof(uid_t));
 584         assert_cc(sizeof(uint32_t) == sizeof(gid_t));
 585
 586         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_UINT32, data))
 587                 return -ENOMEM;
 588
 589         return 0;
 590 }
 591
 592 int bus_property_append_int32(DBusMessageIter *i, const char *property, void *data) {
 593         assert(i);
 594         assert(property);
 595         assert(data);
 596
 597         assert_cc(sizeof(int32_t) == sizeof(int));
 598
 599         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_INT32, data))
 600                 return -ENOMEM;
 601
 602         return 0;
 603 }
 604
 605 int bus_property_append_size(DBusMessageIter *i, const char *property, void *data) {
 606         uint64_t u;
 607
 608         assert(i);
 609         assert(property);
 610         assert(data);
 611
 612         u = (uint64_t) *(size_t*) data;
 613
 614         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_UINT64, &u))
 615                 return -ENOMEM;
 616
 617         return 0;
 618 }
 619
 620 int bus_property_append_ul(DBusMessageIter *i, const char *property, void *data) {
 621         uint64_t u;
 622
 623         assert(i);
 624         assert(property);
 625         assert(data);
 626
 627         u = (uint64_t) *(unsigned long*) data;
 628
 629         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_UINT64, &u))
 630                 return -ENOMEM;
 631
 632         return 0;
 633 }
 634
 635 int bus_property_append_long(DBusMessageIter *i, const char *property, void *data) {
 636         int64_t l;
 637
 638         assert(i);
 639         assert(property);
 640         assert(data);
 641
 642         l = (int64_t) *(long*) data;
 643
 644         if (!dbus_message_iter_append_basic(i, DBUS_TYPE_INT64, &l))
 645                 return -ENOMEM;
 646
 647         return 0;
 648 }
 649
 650 const char *bus_errno_to_dbus(int error) {
 651
 652         switch(error) {
 653
 654         case -EINVAL:
 655                 return DBUS_ERROR_INVALID_ARGS;
 656
 657         case -ENOMEM:
 658                 return DBUS_ERROR_NO_MEMORY;
 659
 660         case -EPERM:
 661         case -EACCES:
 662                 return DBUS_ERROR_ACCESS_DENIED;
 663
 664         case -ESRCH:
 665                 return DBUS_ERROR_UNIX_PROCESS_ID_UNKNOWN;
 666
 667         case -ENOENT:
 668                 return DBUS_ERROR_FILE_NOT_FOUND;
 669
 670         case -EEXIST:
 671                 return DBUS_ERROR_FILE_EXISTS;
 672
 673         case -ETIMEDOUT:
 674         case -ETIME:
 675                 return DBUS_ERROR_TIMEOUT;
 676
 677         case -EIO:
 678                 return DBUS_ERROR_IO_ERROR;
 679
 680         case -ENETRESET:
 681         case -ECONNABORTED:
 682         case -ECONNRESET:
 683                 return DBUS_ERROR_DISCONNECTED;
 684         }
 685
 686         return DBUS_ERROR_FAILED;
 687 }
 688
 689 DBusHandlerResult bus_send_error_reply(DBusConnection *c, DBusMessage *message, DBusError *berror, int error) {
 690         DBusMessage *reply = NULL;
 691         const char *name, *text;
 692
 693         if (berror && dbus_error_is_set(berror)) {
 694                 name = berror->name;
 695                 text = berror->message;
 696         } else {
 697                 name = bus_errno_to_dbus(error);
 698                 text = strerror(-error);
 699         }
 700
 701         if (!(reply = dbus_message_new_error(message, name, text)))
 702                 goto oom;
 703
 704         if (!dbus_connection_send(c, reply, NULL))
 705                 goto oom;
 706
 707         dbus_message_unref(reply);
 708
 709         if (berror)
 710                 dbus_error_free(berror);
 711
 712         return DBUS_HANDLER_RESULT_HANDLED;
 713
 714 oom:
 715         if (reply)
 716                 dbus_message_unref(reply);
 717
 718         if (berror)
 719                 dbus_error_free(berror);
 720
 721         return DBUS_HANDLER_RESULT_NEED_MEMORY;
 722 }
 723
 724 DBusMessage* bus_properties_changed_new(const char *path, const char *interface, const char *properties) {
 725         DBusMessage *m;
 726         DBusMessageIter iter, sub;
 727         const char *i;
 728
 729         assert(interface);
 730         assert(properties);
 731
 732         if (!(m = dbus_message_new_signal(path, "org.freedesktop.DBus.Properties", "PropertiesChanged")))
 733                 goto oom;
 734
 735         dbus_message_iter_init_append(m, &iter);
 736
 737         /* We won't send any property values, since they might be
 738          * large and sometimes not cheap to generated */
 739
 740         if (!dbus_message_iter_append_basic(&iter, DBUS_TYPE_STRING, &interface) ||
 741             !dbus_message_iter_open_container(&iter, DBUS_TYPE_ARRAY, "{sv}", &sub) ||
 742             !dbus_message_iter_close_container(&iter, &sub) ||
 743             !dbus_message_iter_open_container(&iter, DBUS_TYPE_ARRAY, "s", &sub))
 744                 goto oom;
 745
 746         NULSTR_FOREACH(i, properties)
 747                 if (!dbus_message_iter_append_basic(&sub, DBUS_TYPE_STRING, &i))
 748                         goto oom;
 749
 750         if (!dbus_message_iter_close_container(&iter, &sub))
 751                 goto oom;
 752
 753         return m;
 754
 755 oom:
 756         if (m)
 757                 dbus_message_unref(m);
 758
 759         return NULL;
 760 }
 761
 762 uint32_t bus_flags_to_events(DBusWatch *bus_watch) {
 763         unsigned flags;
 764         uint32_t events = 0;
 765
 766         assert(bus_watch);
 767
 768         /* no watch flags for disabled watches */
 769         if (!dbus_watch_get_enabled(bus_watch))
 770                 return 0;
 771
 772         flags = dbus_watch_get_flags(bus_watch);
 773
 774         if (flags & DBUS_WATCH_READABLE)
 775                 events |= EPOLLIN;
 776         if (flags & DBUS_WATCH_WRITABLE)
 777                 events |= EPOLLOUT;
 778
 779         return events | EPOLLHUP | EPOLLERR;
 780 }
 781
 782 unsigned bus_events_to_flags(uint32_t events) {
 783         unsigned flags = 0;
 784
 785         if (events & EPOLLIN)
 786                 flags |= DBUS_WATCH_READABLE;
 787         if (events & EPOLLOUT)
 788                 flags |= DBUS_WATCH_WRITABLE;
 789         if (events & EPOLLHUP)
 790                 flags |= DBUS_WATCH_HANGUP;
 791         if (events & EPOLLERR)
 792                 flags |= DBUS_WATCH_ERROR;
 793
 794         return flags;
 795 }
 796
 797 int bus_parse_strv(DBusMessage *m, char ***_l) {
 798         DBusMessageIter iter;
 799
 800         assert(m);
 801         assert(_l);
 802
 803         if (!dbus_message_iter_init(m, &iter))
 804                 return -EINVAL;
 805
 806         return bus_parse_strv_iter(&iter, _l);
 807 }
 808
 809 int bus_parse_strv_iter(DBusMessageIter *iter, char ***_l) {
 810         DBusMessageIter sub;
 811         unsigned n = 0, i = 0;
 812         char **l;
 813
 814         assert(iter);
 815         assert(_l);
 816
 817         if (dbus_message_iter_get_arg_type(iter) != DBUS_TYPE_ARRAY ||
 818             dbus_message_iter_get_element_type(iter) != DBUS_TYPE_STRING)
 819             return -EINVAL;
 820
 821         dbus_message_iter_recurse(iter, &sub);
 822
 823         while (dbus_message_iter_get_arg_type(&sub) != DBUS_TYPE_INVALID) {
 824                 n++;
 825                 dbus_message_iter_next(&sub);
 826         }
 827
 828         if (!(l = new(char*, n+1)))
 829                 return -ENOMEM;
 830
 831         dbus_message_iter_recurse(iter, &sub);
 832
 833         while (dbus_message_iter_get_arg_type(&sub) != DBUS_TYPE_INVALID) {
 834                 const char *s;
 835
 836                 assert_se(dbus_message_iter_get_arg_type(&sub) == DBUS_TYPE_STRING);
 837                 dbus_message_iter_get_basic(&sub, &s);
 838
 839                 if (!(l[i++] = strdup(s))) {
 840                         strv_free(l);
 841                         return -ENOMEM;
 842                 }
 843
 844                 dbus_message_iter_next(&sub);
 845         }
 846
 847         assert(i == n);
 848         l[i] = NULL;
 849
 850         if (_l)
 851                 *_l = l;
 852
 853         return 0;
 854 }
 855
 856 int bus_append_strv_iter(DBusMessageIter *iter, char **l) {
 857         DBusMessageIter sub;
 858
 859         assert(iter);
 860
 861         if (!dbus_message_iter_open_container(iter, DBUS_TYPE_ARRAY, "s", &sub))
 862                 return -ENOMEM;
 863
 864         STRV_FOREACH(l, l)
 865                 if (!dbus_message_iter_append_basic(&sub, DBUS_TYPE_STRING, l))
 866                         return -ENOMEM;
 867
 868         if (!dbus_message_iter_close_container(iter, &sub))
 869                 return -ENOMEM;
 870
 871         return 0;
 872 }
 873
 874 int bus_iter_get_basic_and_next(DBusMessageIter *iter, int type, void *data, bool next) {
 875
 876         assert(iter);
 877         assert(data);
 878
 879         if (dbus_message_iter_get_arg_type(iter) != type)
 880                 return -EIO;
 881
 882         dbus_message_iter_get_basic(iter, data);
 883
 884         if (!dbus_message_iter_next(iter) != !next)
 885                 return -EIO;
 886
 887         return 0;
 888 }
 889
 890 int generic_print_property(const char *name, DBusMessageIter *iter, bool all) {
 891         assert(name);
 892         assert(iter);
 893
 894         switch (dbus_message_iter_get_arg_type(iter)) {
 895
 896         case DBUS_TYPE_STRING: {
 897                 const char *s;
 898                 dbus_message_iter_get_basic(iter, &s);
 899
 900                 if (all || !isempty(s))
 901                         printf("%s=%s\n", name, s);
 902
 903                 return 1;
 904         }
 905
 906         case DBUS_TYPE_BOOLEAN: {
 907                 dbus_bool_t b;
 908
 909                 dbus_message_iter_get_basic(iter, &b);
 910                 printf("%s=%s\n", name, yes_no(b));
 911
 912                 return 1;
 913         }
 914
 915         case DBUS_TYPE_UINT64: {
 916                 uint64_t u;
 917                 dbus_message_iter_get_basic(iter, &u);
 918
 919                 /* Yes, heuristics! But we can change this check
 920                  * should it turn out to not be sufficient */
 921
 922                 if (endswith(name, "Timestamp")) {
 923                         char timestamp[FORMAT_TIMESTAMP_MAX], *t;
 924
 925                         t = format_timestamp(timestamp, sizeof(timestamp), u);
 926                         if (t || all)
 927                                 printf("%s=%s\n", name, strempty(t));
 928
 929                 } else if (strstr(name, "USec")) {
 930                         char timespan[FORMAT_TIMESPAN_MAX];
 931
 932                         printf("%s=%s\n", name, format_timespan(timespan, sizeof(timespan), u));
 933                 } else
 934                         printf("%s=%llu\n", name, (unsigned long long) u);
 935
 936                 return 1;
 937         }
 938
 939         case DBUS_TYPE_UINT32: {
 940                 uint32_t u;
 941                 dbus_message_iter_get_basic(iter, &u);
 942
 943                 if (strstr(name, "UMask") || strstr(name, "Mode"))
 944                         printf("%s=%04o\n", name, u);
 945                 else
 946                         printf("%s=%u\n", name, (unsigned) u);
 947
 948                 return 1;
 949         }
 950
 951         case DBUS_TYPE_INT32: {
 952                 int32_t i;
 953                 dbus_message_iter_get_basic(iter, &i);
 954
 955                 printf("%s=%i\n", name, (int) i);
 956                 return 1;
 957         }
 958
 959         case DBUS_TYPE_DOUBLE: {
 960                 double d;
 961                 dbus_message_iter_get_basic(iter, &d);
 962
 963                 printf("%s=%g\n", name, d);
 964                 return 1;
 965         }
 966
 967         case DBUS_TYPE_ARRAY:
 968
 969                 if (dbus_message_iter_get_element_type(iter) == DBUS_TYPE_STRING) {
 970                         DBusMessageIter sub;
 971                         bool space = false;
 972
 973                         dbus_message_iter_recurse(iter, &sub);
 974                         if (all ||
 975                             dbus_message_iter_get_arg_type(&sub) != DBUS_TYPE_INVALID) {
 976                                 printf("%s=", name);
 977
 978                                 while (dbus_message_iter_get_arg_type(&sub) != DBUS_TYPE_INVALID) {
 979                                         const char *s;
 980
 981                                         assert(dbus_message_iter_get_arg_type(&sub) == DBUS_TYPE_STRING);
 982                                         dbus_message_iter_get_basic(&sub, &s);
 983                                         printf("%s%s", space ? " " : "", s);
 984
 985                                         space = true;
 986                                         dbus_message_iter_next(&sub);
 987                                 }
 988
 989                                 puts("");
 990                         }
 991
 992                         return 1;
 993
 994                 } else if (dbus_message_iter_get_element_type(iter) == DBUS_TYPE_BYTE) {
 995                         DBusMessageIter sub;
 996
 997                         dbus_message_iter_recurse(iter, &sub);
 998                         if (all ||
 999                             dbus_message_iter_get_arg_type(&sub) != DBUS_TYPE_INVALID) {
1000                                 printf("%s=", name);
1001
1002                                 while (dbus_message_iter_get_arg_type(&sub) != DBUS_TYPE_INVALID) {
1003                                         uint8_t u;
1004
1005                                         assert(dbus_message_iter_get_arg_type(&sub) == DBUS_TYPE_BYTE);
1006                                         dbus_message_iter_get_basic(&sub, &u);
1007                                         printf("%02x", u);
1008
1009                                         dbus_message_iter_next(&sub);
1010                                 }
1011
1012                                 puts("");
1013                         }
1014
1015                         return 1;
1016                 }
1017
1018                 break;
1019         }
1020
1021         return 0;
1022 }
1023
1024 static void release_name_pending_cb(DBusPendingCall *pending, void *userdata) {
1025         DBusMessage *reply;
1026         DBusConnection *bus = userdata;
1027
1028         assert_se(reply = dbus_pending_call_steal_reply(pending));
1029         dbus_message_unref(reply);
1030
1031         dbus_connection_close(bus);
1032 }
1033
1034 void bus_async_unregister_and_exit(DBusConnection *bus, const char *name) {
1035         DBusMessage *m = NULL;
1036         DBusPendingCall *pending = NULL;
1037
1038         assert(bus);
1039
1040         /* We unregister the name here, but we continue to process
1041          * requests, until we get the response for it, so that all
1042          * requests are guaranteed to be processed. */
1043
1044         m = dbus_message_new_method_call(
1045                         DBUS_SERVICE_DBUS,
1046                         DBUS_PATH_DBUS,
1047                         DBUS_INTERFACE_DBUS,
1048                         "ReleaseName");
1049         if (!m)
1050                 goto oom;
1051
1052         if (!dbus_message_append_args(
1053                             m,
1054                             DBUS_TYPE_STRING,
1055                             &name,
1056                             DBUS_TYPE_INVALID))
1057                 goto oom;
1058
1059         if (!dbus_connection_send_with_reply(bus, m, &pending, -1))
1060                 goto oom;
1061
1062         if (!dbus_pending_call_set_notify(pending, release_name_pending_cb, bus, NULL))
1063                 goto oom;
1064
1065         dbus_message_unref(m);
1066         dbus_pending_call_unref(pending);
1067
1068         return;
1069
1070 oom:
1071         log_error("Out of memory");
1072
1073         if (pending) {
1074                 dbus_pending_call_cancel(pending);
1075                 dbus_pending_call_unref(pending);
1076         }
1077
1078         if (m)
1079                 dbus_message_unref(m);
1080 }
1081
1082 DBusHandlerResult bus_exit_idle_filter(DBusConnection *bus, DBusMessage *m, void *userdata) {
1083         usec_t *remain_until = userdata;
1084
1085         assert(bus);
1086         assert(m);
1087         assert(remain_until);
1088
1089         /* Everytime we get a new message we reset out timeout */
1090         *remain_until = now(CLOCK_MONOTONIC) + DEFAULT_EXIT_USEC;
1091
1092         if (dbus_message_is_signal(m, DBUS_INTERFACE_LOCAL, "Disconnected"))
1093                 dbus_connection_close(bus);
1094
1095         return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
1096 }