src/shared/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 Lesser General Public License as published by
  10   the Free Software Foundation; either version 2.1 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   Lesser General Public License for more details.
  17
  18   You should have received a copy of the GNU Lesser 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 }