1 /* -*- mode: C; c-file-style: "gnu" -*- */ 2 /* connection.c Client connections 3 * 4 * Copyright (C) 2003 Red Hat, Inc. 5 * 6 * Licensed under the Academic Free License version 2.1 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it 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 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License 19 * along with this program; if not, write to the Free Software 20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 21 * 22 */ 23 #include "connection.h" 24 #include "dispatch.h" 25 #include "policy.h" 26 #include "services.h" 27 #include "utils.h" 28 #include "signals.h" 29 #include "expirelist.h" 30 #include "selinux.h" 31 #include <dbus/dbus-list.h> 32 #include <dbus/dbus-hash.h> 33 #include <dbus/dbus-timeout.h> 34 35 static void bus_connection_remove_transactions (DBusConnection *connection); 36 37 typedef struct 38 { 39 BusExpireItem expire_item; 40 41 DBusConnection *will_get_reply; 42 DBusConnection *will_send_reply; 43 44 dbus_uint32_t reply_serial; 45 46 } BusPendingReply; 47 48 struct BusConnections 49 { 50 int refcount; 51 DBusList *completed; /**< List of all completed connections */ 52 int n_completed; /**< Length of completed list */ 53 DBusList *incomplete; /**< List of all not-yet-active connections */ 54 int n_incomplete; /**< Length of incomplete list */ 55 BusContext *context; 56 DBusHashTable *completed_by_user; /**< Number of completed connections for each UID */ 57 DBusTimeout *expire_timeout; /**< Timeout for expiring incomplete connections. */ 58 int stamp; /**< Incrementing number */ 59 BusExpireList *pending_replies; /**< List of pending replies */ 60 }; 61 62 static dbus_int32_t connection_data_slot = -1; 63 64 typedef struct 65 { 66 BusConnections *connections; 67 DBusList *link_in_connection_list; 68 DBusConnection *connection; 69 DBusList *services_owned; 70 int n_services_owned; 71 DBusList *match_rules; 72 int n_match_rules; 73 char *name; 74 DBusList *transaction_messages; /**< Stuff we need to send as part of a transaction */ 75 DBusMessage *oom_message; 76 DBusPreallocatedSend *oom_preallocated; 77 BusClientPolicy *policy; 78 79 BusSELinuxID *selinux_id; 80 81 long connection_tv_sec; /**< Time when we connected (seconds component) */ 82 long connection_tv_usec; /**< Time when we connected (microsec component) */ 83 int stamp; /**< connections->stamp last time we were traversed */ 84 } BusConnectionData; 85 86 static dbus_bool_t bus_pending_reply_expired (BusExpireList *list, 87 DBusList *link, 88 void *data); 89 90 static void bus_connection_drop_pending_replies (BusConnections *connections, 91 DBusConnection *connection); 92 93 static dbus_bool_t expire_incomplete_timeout (void *data); 94 95 #define BUS_CONNECTION_DATA(connection) (dbus_connection_get_data ((connection), connection_data_slot)) 96 97 static DBusLoop* 98 connection_get_loop (DBusConnection *connection) 99 { 100 BusConnectionData *d; 101 102 d = BUS_CONNECTION_DATA (connection); 103 104 return bus_context_get_loop (d->connections->context); 105 } 106 107 108 static int 109 get_connections_for_uid (BusConnections *connections, 110 dbus_uid_t uid) 111 { 112 void *val; 113 int current_count; 114 115 /* val is NULL is 0 when it isn't in the hash yet */ 116 117 val = _dbus_hash_table_lookup_ulong (connections->completed_by_user, 118 uid); 119 120 current_count = _DBUS_POINTER_TO_INT (val); 121 122 return current_count; 123 } 124 125 static dbus_bool_t 126 adjust_connections_for_uid (BusConnections *connections, 127 dbus_uid_t uid, 128 int adjustment) 129 { 130 int current_count; 131 132 current_count = get_connections_for_uid (connections, uid); 133 134 _dbus_verbose ("Adjusting connection count for UID " DBUS_UID_FORMAT 135 ": was %d adjustment %d making %d\n", 136 uid, current_count, adjustment, current_count + adjustment); 137 138 _dbus_assert (current_count >= 0); 139 140 current_count += adjustment; 141 142 _dbus_assert (current_count >= 0); 143 144 if (current_count == 0) 145 { 146 _dbus_hash_table_remove_ulong (connections->completed_by_user, uid); 147 return TRUE; 148 } 149 else 150 { 151 dbus_bool_t retval; 152 153 retval = _dbus_hash_table_insert_ulong (connections->completed_by_user, 154 uid, _DBUS_INT_TO_POINTER (current_count)); 155 156 /* only positive adjustment can fail as otherwise 157 * a hash entry should already exist 158 */ 159 _dbus_assert (adjustment > 0 || 160 (adjustment <= 0 && retval)); 161 162 return retval; 163 } 164 } 165 166 void 167 bus_connection_disconnected (DBusConnection *connection) 168 { 169 BusConnectionData *d; 170 BusService *service; 171 BusMatchmaker *matchmaker; 172 173 d = BUS_CONNECTION_DATA (connection); 174 _dbus_assert (d != NULL); 175 176 _dbus_verbose ("%s disconnected, dropping all service ownership and releasing\n", 177 d->name ? d->name : "(inactive)"); 178 179 /* Delete our match rules */ 180 if (d->n_match_rules > 0) 181 { 182 matchmaker = bus_context_get_matchmaker (d->connections->context); 183 bus_matchmaker_disconnected (matchmaker, connection); 184 } 185 186 /* Drop any service ownership. Unfortunately, this requires 187 * memory allocation and there doesn't seem to be a good way to 188 * handle it other than sleeping; we can't "fail" the operation of 189 * disconnecting a client, and preallocating a broadcast "service is 190 * now gone" message for every client-service pair seems kind of 191 * involved. 192 */ 193 while ((service = _dbus_list_get_last (&d->services_owned))) 194 { 195 BusTransaction *transaction; 196 DBusError error; 197 198 retry: 199 200 dbus_error_init (&error); 201 202 while ((transaction = bus_transaction_new (d->connections->context)) == NULL) 203 _dbus_wait_for_memory (); 204 205 if (!bus_service_remove_owner (service, connection, 206 transaction, &error)) 207 { 208 _DBUS_ASSERT_ERROR_IS_SET (&error); 209 210 if (dbus_error_has_name (&error, DBUS_ERROR_NO_MEMORY)) 211 { 212 dbus_error_free (&error); 213 bus_transaction_cancel_and_free (transaction); 214 _dbus_wait_for_memory (); 215 goto retry; 216 } 217 else 218 { 219 _dbus_verbose ("Failed to remove service owner: %s %s\n", 220 error.name, error.message); 221 _dbus_assert_not_reached ("Removing service owner failed for non-memory-related reason"); 222 } 223 } 224 225 bus_transaction_execute_and_free (transaction); 226 } 227 228 bus_dispatch_remove_connection (connection); 229 230 /* no more watching */ 231 if (!dbus_connection_set_watch_functions (connection, 232 NULL, NULL, NULL, 233 connection, 234 NULL)) 235 _dbus_assert_not_reached ("setting watch functions to NULL failed"); 236 237 if (!dbus_connection_set_timeout_functions (connection, 238 NULL, NULL, NULL, 239 connection, 240 NULL)) 241 _dbus_assert_not_reached ("setting timeout functions to NULL failed"); 242 243 dbus_connection_set_unix_user_function (connection, 244 NULL, NULL, NULL); 245 246 dbus_connection_set_dispatch_status_function (connection, 247 NULL, NULL, NULL); 248 249 bus_connection_remove_transactions (connection); 250 251 if (d->link_in_connection_list != NULL) 252 { 253 if (d->name != NULL) 254 { 255 unsigned long uid; 256 257 _dbus_list_remove_link (&d->connections->completed, d->link_in_connection_list); 258 d->link_in_connection_list = NULL; 259 d->connections->n_completed -= 1; 260 261 if (dbus_connection_get_unix_user (connection, &uid)) 262 { 263 if (!adjust_connections_for_uid (d->connections, 264 uid, -1)) 265 _dbus_assert_not_reached ("adjusting downward should never fail"); 266 } 267 } 268 else 269 { 270 _dbus_list_remove_link (&d->connections->incomplete, d->link_in_connection_list); 271 d->link_in_connection_list = NULL; 272 d->connections->n_incomplete -= 1; 273 } 274 275 _dbus_assert (d->connections->n_incomplete >= 0); 276 _dbus_assert (d->connections->n_completed >= 0); 277 } 278 279 bus_connection_drop_pending_replies (d->connections, connection); 280 281 /* frees "d" as side effect */ 282 dbus_connection_set_data (connection, 283 connection_data_slot, 284 NULL, NULL); 285 286 dbus_connection_unref (connection); 287 } 288 289 static dbus_bool_t 290 connection_watch_callback (DBusWatch *watch, 291 unsigned int condition, 292 void *data) 293 { 294 /* FIXME this can be done in dbus-mainloop.c 295 * if the code in activation.c for the babysitter 296 * watch handler is fixed. 297 */ 298 299 #if 0 300 _dbus_verbose ("Calling handle_watch\n"); 301 #endif 302 return dbus_watch_handle (watch, condition); 303 } 304 305 static dbus_bool_t 306 add_connection_watch (DBusWatch *watch, 307 void *data) 308 { 309 DBusConnection *connection = data; 310 311 return _dbus_loop_add_watch (connection_get_loop (connection), 312 watch, connection_watch_callback, connection, 313 NULL); 314 } 315 316 static void 317 remove_connection_watch (DBusWatch *watch, 318 void *data) 319 { 320 DBusConnection *connection = data; 321 322 _dbus_loop_remove_watch (connection_get_loop (connection), 323 watch, connection_watch_callback, connection); 324 } 325 326 static void 327 connection_timeout_callback (DBusTimeout *timeout, 328 void *data) 329 { 330 /* DBusConnection *connection = data; */ 331 332 /* can return FALSE on OOM but we just let it fire again later */ 333 dbus_timeout_handle (timeout); 334 } 335 336 static dbus_bool_t 337 add_connection_timeout (DBusTimeout *timeout, 338 void *data) 339 { 340 DBusConnection *connection = data; 341 342 return _dbus_loop_add_timeout (connection_get_loop (connection), 343 timeout, connection_timeout_callback, connection, NULL); 344 } 345 346 static void 347 remove_connection_timeout (DBusTimeout *timeout, 348 void *data) 349 { 350 DBusConnection *connection = data; 351 352 _dbus_loop_remove_timeout (connection_get_loop (connection), 353 timeout, connection_timeout_callback, connection); 354 } 355 356 static void 357 dispatch_status_function (DBusConnection *connection, 358 DBusDispatchStatus new_status, 359 void *data) 360 { 361 DBusLoop *loop = data; 362 363 if (new_status != DBUS_DISPATCH_COMPLETE) 364 { 365 while (!_dbus_loop_queue_dispatch (loop, connection)) 366 _dbus_wait_for_memory (); 367 } 368 } 369 370 static dbus_bool_t 371 allow_user_function (DBusConnection *connection, 372 unsigned long uid, 373 void *data) 374 { 375 BusConnectionData *d; 376 377 d = BUS_CONNECTION_DATA (connection); 378 379 _dbus_assert (d != NULL); 380 381 return bus_context_allow_user (d->connections->context, uid); 382 } 383 384 static void 385 free_connection_data (void *data) 386 { 387 BusConnectionData *d = data; 388 389 /* services_owned should be NULL since we should be disconnected */ 390 _dbus_assert (d->services_owned == NULL); 391 _dbus_assert (d->n_services_owned == 0); 392 /* similarly */ 393 _dbus_assert (d->transaction_messages == NULL); 394 395 if (d->oom_preallocated) 396 dbus_connection_free_preallocated_send (d->connection, d->oom_preallocated); 397 398 if (d->oom_message) 399 dbus_message_unref (d->oom_message); 400 401 if (d->policy) 402 bus_client_policy_unref (d->policy); 403 404 if (d->selinux_id) 405 bus_selinux_id_unref (d->selinux_id); 406 407 dbus_free (d->name); 408 409 dbus_free (d); 410 } 411 412 static void 413 call_timeout_callback (DBusTimeout *timeout, 414 void *data) 415 { 416 /* can return FALSE on OOM but we just let it fire again later */ 417 dbus_timeout_handle (timeout); 418 } 419 420 BusConnections* 421 bus_connections_new (BusContext *context) 422 { 423 BusConnections *connections; 424 425 if (!dbus_connection_allocate_data_slot (&connection_data_slot)) 426 goto failed_0; 427 428 connections = dbus_new0 (BusConnections, 1); 429 if (connections == NULL) 430 goto failed_1; 431 432 connections->completed_by_user = _dbus_hash_table_new (DBUS_HASH_ULONG, 433 NULL, NULL); 434 if (connections->completed_by_user == NULL) 435 goto failed_2; 436 437 connections->expire_timeout = _dbus_timeout_new (100, /* irrelevant */ 438 expire_incomplete_timeout, 439 connections, NULL); 440 if (connections->expire_timeout == NULL) 441 goto failed_3; 442 443 _dbus_timeout_set_enabled (connections->expire_timeout, FALSE); 444 445 connections->pending_replies = bus_expire_list_new (bus_context_get_loop (context), 446 bus_context_get_reply_timeout (context), 447 bus_pending_reply_expired, 448 connections); 449 if (connections->pending_replies == NULL) 450 goto failed_4; 451 452 if (!_dbus_loop_add_timeout (bus_context_get_loop (context), 453 connections->expire_timeout, 454 call_timeout_callback, NULL, NULL)) 455 goto failed_5; 456 457 connections->refcount = 1; 458 connections->context = context; 459 460 return connections; 461 462 failed_5: 463 bus_expire_list_free (connections->pending_replies); 464 failed_4: 465 _dbus_timeout_unref (connections->expire_timeout); 466 failed_3: 467 _dbus_hash_table_unref (connections->completed_by_user); 468 failed_2: 469 dbus_free (connections); 470 failed_1: 471 dbus_connection_free_data_slot (&connection_data_slot); 472 failed_0: 473 return NULL; 474 } 475 476 BusConnections * 477 bus_connections_ref (BusConnections *connections) 478 { 479 _dbus_assert (connections->refcount > 0); 480 connections->refcount += 1; 481 482 return connections; 483 } 484 485 void 486 bus_connections_unref (BusConnections *connections) 487 { 488 _dbus_assert (connections->refcount > 0); 489 connections->refcount -= 1; 490 if (connections->refcount == 0) 491 { 492 /* drop all incomplete */ 493 while (connections->incomplete != NULL) 494 { 495 DBusConnection *connection; 496 497 connection = connections->incomplete->data; 498 499 dbus_connection_ref (connection); 500 dbus_connection_close (connection); 501 bus_connection_disconnected (connection); 502 dbus_connection_unref (connection); 503 } 504 505 _dbus_assert (connections->n_incomplete == 0); 506 507 /* drop all real connections */ 508 while (connections->completed != NULL) 509 { 510 DBusConnection *connection; 511 512 connection = connections->completed->data; 513 514 dbus_connection_ref (connection); 515 dbus_connection_close (connection); 516 bus_connection_disconnected (connection); 517 dbus_connection_unref (connection); 518 } 519 520 _dbus_assert (connections->n_completed == 0); 521 522 bus_expire_list_free (connections->pending_replies); 523 524 _dbus_loop_remove_timeout (bus_context_get_loop (connections->context), 525 connections->expire_timeout, 526 call_timeout_callback, NULL); 527 528 _dbus_timeout_unref (connections->expire_timeout); 529 530 _dbus_hash_table_unref (connections->completed_by_user); 531 532 dbus_free (connections); 533 534 dbus_connection_free_data_slot (&connection_data_slot); 535 } 536 } 537 538 dbus_bool_t 539 bus_connections_setup_connection (BusConnections *connections, 540 DBusConnection *connection) 541 { 542 BusConnectionData *d; 543 dbus_bool_t retval; 544 DBusError error; 545 546 d = dbus_new0 (BusConnectionData, 1); 547 548 if (d == NULL) 549 return FALSE; 550 551 d->connections = connections; 552 d->connection = connection; 553 554 _dbus_get_current_time (&d->connection_tv_sec, 555 &d->connection_tv_usec); 556 557 _dbus_assert (connection_data_slot >= 0); 558 559 if (!dbus_connection_set_data (connection, 560 connection_data_slot, 561 d, free_connection_data)) 562 { 563 dbus_free (d); 564 return FALSE; 565 } 566 567 dbus_connection_set_route_peer_messages (connection, TRUE); 568 569 retval = FALSE; 570 571 dbus_error_init (&error); 572 d->selinux_id = bus_selinux_init_connection_id (connection, 573 &error); 574 if (dbus_error_is_set (&error)) 575 { 576 /* This is a bit bogus because we pretend all errors 577 * are OOM; this is done because we know that in bus.c 578 * an OOM error disconnects the connection, which is 579 * the same thing we want on any other error. 580 */ 581 dbus_error_free (&error); 582 goto out; 583 } 584 585 if (!dbus_connection_set_watch_functions (connection, 586 add_connection_watch, 587 remove_connection_watch, 588 NULL, 589 connection, 590 NULL)) 591 goto out; 592 593 if (!dbus_connection_set_timeout_functions (connection, 594 add_connection_timeout, 595 remove_connection_timeout, 596 NULL, 597 connection, NULL)) 598 goto out; 599 600 dbus_connection_set_unix_user_function (connection, 601 allow_user_function, 602 NULL, NULL); 603 604 dbus_connection_set_dispatch_status_function (connection, 605 dispatch_status_function, 606 bus_context_get_loop (connections->context), 607 NULL); 608 609 d->link_in_connection_list = _dbus_list_alloc_link (connection); 610 if (d->link_in_connection_list == NULL) 611 goto out; 612 613 /* Setup the connection with the dispatcher */ 614 if (!bus_dispatch_add_connection (connection)) 615 goto out; 616 617 if (dbus_connection_get_dispatch_status (connection) != DBUS_DISPATCH_COMPLETE) 618 { 619 if (!_dbus_loop_queue_dispatch (bus_context_get_loop (connections->context), connection)) 620 { 621 bus_dispatch_remove_connection (connection); 622 goto out; 623 } 624 } 625 626 _dbus_list_append_link (&connections->incomplete, d->link_in_connection_list); 627 connections->n_incomplete += 1; 628 629 dbus_connection_ref (connection); 630 631 /* Note that we might disconnect ourselves here, but it only takes 632 * effect on return to the main loop. We call this to free up 633 * expired connections if possible, and to queue the timeout for our 634 * own expiration. 635 */ 636 bus_connections_expire_incomplete (connections); 637 638 /* And we might also disconnect ourselves here, but again it 639 * only takes effect on return to main loop. 640 */ 641 if (connections->n_incomplete > 642 bus_context_get_max_incomplete_connections (connections->context)) 643 { 644 _dbus_verbose ("Number of incomplete connections exceeds max, dropping oldest one\n"); 645 646 _dbus_assert (connections->incomplete != NULL); 647 /* Disconnect the oldest unauthenticated connection. FIXME 648 * would it be more secure to drop a *random* connection? This 649 * algorithm seems to mean that if someone can create new 650 * connections quickly enough, they can keep anyone else from 651 * completing authentication. But random may or may not really 652 * help with that, a more elaborate solution might be required. 653 */ 654 dbus_connection_close (connections->incomplete->data); 655 } 656 657 retval = TRUE; 658 659 out: 660 if (!retval) 661 { 662 if (d->selinux_id) 663 bus_selinux_id_unref (d->selinux_id); 664 d->selinux_id = NULL; 665 666 if (!dbus_connection_set_watch_functions (connection, 667 NULL, NULL, NULL, 668 connection, 669 NULL)) 670 _dbus_assert_not_reached ("setting watch functions to NULL failed"); 671 672 if (!dbus_connection_set_timeout_functions (connection, 673 NULL, NULL, NULL, 674 connection, 675 NULL)) 676 _dbus_assert_not_reached ("setting timeout functions to NULL failed"); 677 678 dbus_connection_set_unix_user_function (connection, 679 NULL, NULL, NULL); 680 681 dbus_connection_set_dispatch_status_function (connection, 682 NULL, NULL, NULL); 683 684 if (d->link_in_connection_list != NULL) 685 { 686 _dbus_assert (d->link_in_connection_list->next == NULL); 687 _dbus_assert (d->link_in_connection_list->prev == NULL); 688 _dbus_list_free_link (d->link_in_connection_list); 689 d->link_in_connection_list = NULL; 690 } 691 692 if (!dbus_connection_set_data (connection, 693 connection_data_slot, 694 NULL, NULL)) 695 _dbus_assert_not_reached ("failed to set connection data to null"); 696 697 /* "d" has now been freed */ 698 } 699 700 return retval; 701 } 702 703 void 704 bus_connections_expire_incomplete (BusConnections *connections) 705 { 706 int next_interval; 707 708 next_interval = -1; 709 710 if (connections->incomplete != NULL) 711 { 712 long tv_sec, tv_usec; 713 DBusList *link; 714 int auth_timeout; 715 716 _dbus_get_current_time (&tv_sec, &tv_usec); 717 auth_timeout = bus_context_get_auth_timeout (connections->context); 718 719 link = _dbus_list_get_first_link (&connections->incomplete); 720 while (link != NULL) 721 { 722 DBusList *next = _dbus_list_get_next_link (&connections->incomplete, link); 723 DBusConnection *connection; 724 BusConnectionData *d; 725 double elapsed; 726 727 connection = link->data; 728 729 d = BUS_CONNECTION_DATA (connection); 730 731 _dbus_assert (d != NULL); 732 733 elapsed = ELAPSED_MILLISECONDS_SINCE (d->connection_tv_sec, 734 d->connection_tv_usec, 735 tv_sec, tv_usec); 736 737 if (elapsed >= (double) auth_timeout) 738 { 739 _dbus_verbose ("Timing out authentication for connection %p\n", connection); 740 dbus_connection_close (connection); 741 } 742 else 743 { 744 /* We can end the loop, since the connections are in oldest-first order */ 745 next_interval = ((double)auth_timeout) - elapsed; 746 _dbus_verbose ("Connection %p authentication expires in %d milliseconds\n", 747 connection, next_interval); 748 749 break; 750 } 751 752 link = next; 753 } 754 } 755 756 bus_expire_timeout_set_interval (connections->expire_timeout, 757 next_interval); 758 } 759 760 static dbus_bool_t 761 expire_incomplete_timeout (void *data) 762 { 763 BusConnections *connections = data; 764 765 _dbus_verbose ("Running %s\n", _DBUS_FUNCTION_NAME); 766 767 /* note that this may remove the timeout */ 768 bus_connections_expire_incomplete (connections); 769 770 return TRUE; 771 } 772 773 dbus_bool_t 774 bus_connection_get_groups (DBusConnection *connection, 775 unsigned long **groups, 776 int *n_groups, 777 DBusError *error) 778 { 779 BusConnectionData *d; 780 unsigned long uid; 781 DBusUserDatabase *user_database; 782 783 d = BUS_CONNECTION_DATA (connection); 784 785 _dbus_assert (d != NULL); 786 787 user_database = bus_context_get_user_database (d->connections->context); 788 789 *groups = NULL; 790 *n_groups = 0; 791 792 if (dbus_connection_get_unix_user (connection, &uid)) 793 { 794 if (!_dbus_user_database_get_groups (user_database, 795 uid, groups, n_groups, 796 error)) 797 { 798 _DBUS_ASSERT_ERROR_IS_SET (error); 799 _dbus_verbose ("Did not get any groups for UID %lu\n", 800 uid); 801 return FALSE; 802 } 803 else 804 { 805 _dbus_verbose ("Got %d groups for UID %lu\n", 806 *n_groups, uid); 807 return TRUE; 808 } 809 } 810 else 811 return TRUE; /* successfully got 0 groups */ 812 } 813 814 dbus_bool_t 815 bus_connection_is_in_group (DBusConnection *connection, 816 unsigned long gid) 817 { 818 int i; 819 unsigned long *group_ids; 820 int n_group_ids; 821 822 if (!bus_connection_get_groups (connection, &group_ids, &n_group_ids, 823 NULL)) 824 return FALSE; 825 826 i = 0; 827 while (i < n_group_ids) 828 { 829 if (group_ids[i] == gid) 830 { 831 dbus_free (group_ids); 832 return TRUE; 833 } 834 ++i; 835 } 836 837 dbus_free (group_ids); 838 return FALSE; 839 } 840 841 BusClientPolicy* 842 bus_connection_get_policy (DBusConnection *connection) 843 { 844 BusConnectionData *d; 845 846 d = BUS_CONNECTION_DATA (connection); 847 848 _dbus_assert (d != NULL); 849 _dbus_assert (d->policy != NULL); 850 851 return d->policy; 852 } 853 854 static dbus_bool_t 855 foreach_active (BusConnections *connections, 856 BusConnectionForeachFunction function, 857 void *data) 858 { 859 DBusList *link; 860 861 link = _dbus_list_get_first_link (&connections->completed); 862 while (link != NULL) 863 { 864 DBusConnection *connection = link->data; 865 DBusList *next = _dbus_list_get_next_link (&connections->completed, link); 866 867 if (!(* function) (connection, data)) 868 return FALSE; 869 870 link = next; 871 } 872 873 return TRUE; 874 } 875 876 static dbus_bool_t 877 foreach_inactive (BusConnections *connections, 878 BusConnectionForeachFunction function, 879 void *data) 880 { 881 DBusList *link; 882 883 link = _dbus_list_get_first_link (&connections->incomplete); 884 while (link != NULL) 885 { 886 DBusConnection *connection = link->data; 887 DBusList *next = _dbus_list_get_next_link (&connections->incomplete, link); 888 889 if (!(* function) (connection, data)) 890 return FALSE; 891 892 link = next; 893 } 894 895 return TRUE; 896 } 897 898 /** 899 * Calls function on each active connection; if the function returns 900 * #FALSE, stops iterating. Active connections are authenticated 901 * and have sent a Hello message. 902 * 903 * @param connections the connections object 904 * @param function the function 905 * @param data data to pass to it as a second arg 906 */ 907 void 908 bus_connections_foreach_active (BusConnections *connections, 909 BusConnectionForeachFunction function, 910 void *data) 911 { 912 foreach_active (connections, function, data); 913 } 914 915 /** 916 * Calls function on each connection; if the function returns 917 * #FALSE, stops iterating. 918 * 919 * @param connections the connections object 920 * @param function the function 921 * @param data data to pass to it as a second arg 922 */ 923 void 924 bus_connections_foreach (BusConnections *connections, 925 BusConnectionForeachFunction function, 926 void *data) 927 { 928 if (!foreach_active (connections, function, data)) 929 return; 930 931 foreach_inactive (connections, function, data); 932 } 933 934 BusContext* 935 bus_connections_get_context (BusConnections *connections) 936 { 937 return connections->context; 938 } 939 940 /* 941 * This is used to avoid covering the same connection twice when 942 * traversing connections. Note that it assumes we will 943 * bus_connection_mark_stamp() each connection at least once per 944 * INT_MAX increments of the global stamp, or wraparound would break 945 * things. 946 */ 947 void 948 bus_connections_increment_stamp (BusConnections *connections) 949 { 950 connections->stamp += 1; 951 } 952 953 /* Mark connection with current stamp, return TRUE if it 954 * didn't already have that stamp 955 */ 956 dbus_bool_t 957 bus_connection_mark_stamp (DBusConnection *connection) 958 { 959 BusConnectionData *d; 960 961 d = BUS_CONNECTION_DATA (connection); 962 963 _dbus_assert (d != NULL); 964 965 if (d->stamp == d->connections->stamp) 966 return FALSE; 967 else 968 { 969 d->stamp = d->connections->stamp; 970 return TRUE; 971 } 972 } 973 974 BusContext* 975 bus_connection_get_context (DBusConnection *connection) 976 { 977 BusConnectionData *d; 978 979 d = BUS_CONNECTION_DATA (connection); 980 981 _dbus_assert (d != NULL); 982 983 return d->connections->context; 984 } 985 986 BusConnections* 987 bus_connection_get_connections (DBusConnection *connection) 988 { 989 BusConnectionData *d; 990 991 d = BUS_CONNECTION_DATA (connection); 992 993 _dbus_assert (d != NULL); 994 995 return d->connections; 996 } 997 998 BusRegistry* 999 bus_connection_get_registry (DBusConnection *connection) 1000 { 1001 BusConnectionData *d; 1002 1003 d = BUS_CONNECTION_DATA (connection); 1004 1005 _dbus_assert (d != NULL); 1006 1007 return bus_context_get_registry (d->connections->context); 1008 } 1009 1010 BusActivation* 1011 bus_connection_get_activation (DBusConnection *connection) 1012 { 1013 BusConnectionData *d; 1014 1015 d = BUS_CONNECTION_DATA (connection); 1016 1017 _dbus_assert (d != NULL); 1018 1019 return bus_context_get_activation (d->connections->context); 1020 } 1021 1022 BusMatchmaker* 1023 bus_connection_get_matchmaker (DBusConnection *connection) 1024 { 1025 BusConnectionData *d; 1026 1027 d = BUS_CONNECTION_DATA (connection); 1028 1029 _dbus_assert (d != NULL); 1030 1031 return bus_context_get_matchmaker (d->connections->context); 1032 } 1033 1034 BusSELinuxID* 1035 bus_connection_get_selinux_id (DBusConnection *connection) 1036 { 1037 BusConnectionData *d; 1038 1039 d = BUS_CONNECTION_DATA (connection); 1040 1041 _dbus_assert (d != NULL); 1042 1043 return d->selinux_id; 1044 } 1045 1046 /** 1047 * Checks whether the connection is registered with the message bus. 1048 * 1049 * @param connection the connection 1050 * @returns #TRUE if we're an active message bus participant 1051 */ 1052 dbus_bool_t 1053 bus_connection_is_active (DBusConnection *connection) 1054 { 1055 BusConnectionData *d; 1056 1057 d = BUS_CONNECTION_DATA (connection); 1058 1059 return d != NULL && d->name != NULL; 1060 } 1061 1062 dbus_bool_t 1063 bus_connection_preallocate_oom_error (DBusConnection *connection) 1064 { 1065 DBusMessage *message; 1066 DBusPreallocatedSend *preallocated; 1067 BusConnectionData *d; 1068 1069 d = BUS_CONNECTION_DATA (connection); 1070 1071 _dbus_assert (d != NULL); 1072 1073 if (d->oom_preallocated != NULL) 1074 return TRUE; 1075 1076 preallocated = dbus_connection_preallocate_send (connection); 1077 if (preallocated == NULL) 1078 return FALSE; 1079 1080 message = dbus_message_new (DBUS_MESSAGE_TYPE_ERROR); 1081 1082 if (message == NULL) 1083 { 1084 dbus_connection_free_preallocated_send (connection, preallocated); 1085 return FALSE; 1086 } 1087 1088 /* d->name may be NULL, but that is OK */ 1089 if (!dbus_message_set_error_name (message, DBUS_ERROR_NO_MEMORY) || 1090 !dbus_message_set_destination (message, d->name) || 1091 !dbus_message_set_sender (message, 1092 DBUS_SERVICE_DBUS)) 1093 { 1094 dbus_connection_free_preallocated_send (connection, preallocated); 1095 dbus_message_unref (message); 1096 return FALSE; 1097 } 1098 1099 /* set reply serial to placeholder value just so space is already allocated 1100 * for it. 1101 */ 1102 if (!dbus_message_set_reply_serial (message, 14)) 1103 { 1104 dbus_connection_free_preallocated_send (connection, preallocated); 1105 dbus_message_unref (message); 1106 return FALSE; 1107 } 1108 1109 d->oom_message = message; 1110 d->oom_preallocated = preallocated; 1111 1112 return TRUE; 1113 } 1114 1115 void 1116 bus_connection_send_oom_error (DBusConnection *connection, 1117 DBusMessage *in_reply_to) 1118 { 1119 BusConnectionData *d; 1120 1121 d = BUS_CONNECTION_DATA (connection); 1122 1123 _dbus_assert (d != NULL); 1124 _dbus_assert (d->oom_message != NULL); 1125 1126 /* should always succeed since we set it to a placeholder earlier */ 1127 if (!dbus_message_set_reply_serial (d->oom_message, 1128 dbus_message_get_serial (in_reply_to))) 1129 _dbus_assert_not_reached ("Failed to set reply serial for preallocated oom message"); 1130 1131 _dbus_assert (dbus_message_get_sender (d->oom_message) != NULL); 1132 1133 dbus_connection_send_preallocated (connection, d->oom_preallocated, 1134 d->oom_message, NULL); 1135 1136 dbus_message_unref (d->oom_message); 1137 d->oom_message = NULL; 1138 d->oom_preallocated = NULL; 1139 } 1140 1141 void 1142 bus_connection_add_match_rule_link (DBusConnection *connection, 1143 DBusList *link) 1144 { 1145 BusConnectionData *d; 1146 1147 d = BUS_CONNECTION_DATA (connection); 1148 _dbus_assert (d != NULL); 1149 1150 _dbus_list_append_link (&d->match_rules, link); 1151 1152 d->n_match_rules += 1; 1153 } 1154 1155 dbus_bool_t 1156 bus_connection_add_match_rule (DBusConnection *connection, 1157 BusMatchRule *rule) 1158 { 1159 DBusList *link; 1160 1161 link = _dbus_list_alloc_link (rule); 1162 1163 if (link == NULL) 1164 return FALSE; 1165 1166 bus_connection_add_match_rule_link (connection, link); 1167 1168 return TRUE; 1169 } 1170 1171 void 1172 bus_connection_remove_match_rule (DBusConnection *connection, 1173 BusMatchRule *rule) 1174 { 1175 BusConnectionData *d; 1176 1177 d = BUS_CONNECTION_DATA (connection); 1178 _dbus_assert (d != NULL); 1179 1180 _dbus_list_remove_last (&d->match_rules, rule); 1181 1182 d->n_match_rules -= 1; 1183 _dbus_assert (d->n_match_rules >= 0); 1184 } 1185 1186 int 1187 bus_connection_get_n_match_rules (DBusConnection *connection) 1188 { 1189 BusConnectionData *d; 1190 1191 d = BUS_CONNECTION_DATA (connection); 1192 _dbus_assert (d != NULL); 1193 1194 return d->n_match_rules; 1195 } 1196 1197 void 1198 bus_connection_add_owned_service_link (DBusConnection *connection, 1199 DBusList *link) 1200 { 1201 BusConnectionData *d; 1202 1203 d = BUS_CONNECTION_DATA (connection); 1204 _dbus_assert (d != NULL); 1205 1206 _dbus_list_append_link (&d->services_owned, link); 1207 1208 d->n_services_owned += 1; 1209 } 1210 1211 dbus_bool_t 1212 bus_connection_add_owned_service (DBusConnection *connection, 1213 BusService *service) 1214 { 1215 DBusList *link; 1216 1217 link = _dbus_list_alloc_link (service); 1218 1219 if (link == NULL) 1220 return FALSE; 1221 1222 bus_connection_add_owned_service_link (connection, link); 1223 1224 return TRUE; 1225 } 1226 1227 void 1228 bus_connection_remove_owned_service (DBusConnection *connection, 1229 BusService *service) 1230 { 1231 BusConnectionData *d; 1232 1233 d = BUS_CONNECTION_DATA (connection); 1234 _dbus_assert (d != NULL); 1235 1236 _dbus_list_remove_last (&d->services_owned, service); 1237 1238 d->n_services_owned -= 1; 1239 _dbus_assert (d->n_services_owned >= 0); 1240 } 1241 1242 int 1243 bus_connection_get_n_services_owned (DBusConnection *connection) 1244 { 1245 BusConnectionData *d; 1246 1247 d = BUS_CONNECTION_DATA (connection); 1248 _dbus_assert (d != NULL); 1249 1250 return d->n_services_owned; 1251 } 1252 1253 dbus_bool_t 1254 bus_connection_complete (DBusConnection *connection, 1255 const DBusString *name, 1256 DBusError *error) 1257 { 1258 BusConnectionData *d; 1259 unsigned long uid; 1260 1261 d = BUS_CONNECTION_DATA (connection); 1262 _dbus_assert (d != NULL); 1263 _dbus_assert (d->name == NULL); 1264 _dbus_assert (d->policy == NULL); 1265 1266 _dbus_assert (!bus_connection_is_active (connection)); 1267 1268 if (!_dbus_string_copy_data (name, &d->name)) 1269 { 1270 BUS_SET_OOM (error); 1271 return FALSE; 1272 } 1273 1274 _dbus_assert (d->name != NULL); 1275 1276 _dbus_verbose ("Name %s assigned to %p\n", d->name, connection); 1277 1278 d->policy = bus_context_create_client_policy (d->connections->context, 1279 connection, 1280 error); 1281 1282 /* we may have a NULL policy on OOM or error getting list of 1283 * groups for a user. In the latter case we don't handle it so 1284 * well currently, as it will just keep failing over and over. 1285 */ 1286 1287 if (d->policy == NULL) 1288 { 1289 _dbus_verbose ("Failed to create security policy for connection %p\n", 1290 connection); 1291 _DBUS_ASSERT_ERROR_IS_SET (error); 1292 dbus_free (d->name); 1293 d->name = NULL; 1294 return FALSE; 1295 } 1296 1297 if (dbus_connection_get_unix_user (connection, &uid)) 1298 { 1299 if (!adjust_connections_for_uid (d->connections, 1300 uid, 1)) 1301 { 1302 BUS_SET_OOM (error); 1303 dbus_free (d->name); 1304 d->name = NULL; 1305 return FALSE; 1306 } 1307 } 1308 1309 /* Now the connection is active, move it between lists */ 1310 _dbus_list_unlink (&d->connections->incomplete, 1311 d->link_in_connection_list); 1312 d->connections->n_incomplete -= 1; 1313 _dbus_list_append_link (&d->connections->completed, 1314 d->link_in_connection_list); 1315 d->connections->n_completed += 1; 1316 1317 _dbus_assert (d->connections->n_incomplete >= 0); 1318 _dbus_assert (d->connections->n_completed > 0); 1319 1320 /* See if we can remove the timeout */ 1321 bus_connections_expire_incomplete (d->connections); 1322 1323 _dbus_assert (bus_connection_is_active (connection)); 1324 1325 return TRUE; 1326 } 1327 1328 const char * 1329 bus_connection_get_name (DBusConnection *connection) 1330 { 1331 BusConnectionData *d; 1332 1333 d = BUS_CONNECTION_DATA (connection); 1334 _dbus_assert (d != NULL); 1335 1336 return d->name; 1337 } 1338 1339 /** 1340 * Check whether completing the passed-in connection would 1341 * exceed limits, and if so set error and return #FALSE 1342 */ 1343 dbus_bool_t 1344 bus_connections_check_limits (BusConnections *connections, 1345 DBusConnection *requesting_completion, 1346 DBusError *error) 1347 { 1348 BusConnectionData *d; 1349 unsigned long uid; 1350 1351 d = BUS_CONNECTION_DATA (requesting_completion); 1352 _dbus_assert (d != NULL); 1353 1354 _dbus_assert (d->name == NULL); 1355 1356 if (connections->n_completed >= 1357 bus_context_get_max_completed_connections (connections->context)) 1358 { 1359 dbus_set_error (error, DBUS_ERROR_LIMITS_EXCEEDED, 1360 "The maximum number of active connections has been reached"); 1361 return FALSE; 1362 } 1363 1364 if (dbus_connection_get_unix_user (requesting_completion, &uid)) 1365 { 1366 if (get_connections_for_uid (connections, uid) >= 1367 bus_context_get_max_connections_per_user (connections->context)) 1368 { 1369 dbus_set_error (error, DBUS_ERROR_LIMITS_EXCEEDED, 1370 "The maximum number of active connections for UID %lu has been reached", 1371 uid); 1372 return FALSE; 1373 } 1374 } 1375 1376 return TRUE; 1377 } 1378 1379 static void 1380 bus_pending_reply_free (BusPendingReply *pending) 1381 { 1382 _dbus_verbose ("Freeing pending reply %p, replier %p receiver %p serial %u\n", 1383 pending, 1384 pending->will_send_reply, 1385 pending->will_get_reply, 1386 pending->reply_serial); 1387 1388 dbus_free (pending); 1389 } 1390 1391 static dbus_bool_t 1392 bus_pending_reply_send_no_reply (BusConnections *connections, 1393 BusTransaction *transaction, 1394 BusPendingReply *pending) 1395 { 1396 DBusMessage *message; 1397 DBusMessageIter iter; 1398 dbus_bool_t retval; 1399 const char *errmsg; 1400 1401 retval = FALSE; 1402 1403 message = dbus_message_new (DBUS_MESSAGE_TYPE_ERROR); 1404 if (message == NULL) 1405 return FALSE; 1406 1407 dbus_message_set_no_reply (message, TRUE); 1408 1409 if (!dbus_message_set_reply_serial (message, 1410 pending->reply_serial)) 1411 goto out; 1412 1413 if (!dbus_message_set_error_name (message, 1414 DBUS_ERROR_NO_REPLY)) 1415 goto out; 1416 1417 errmsg = "Message did not receive a reply (timeout by message bus)"; 1418 dbus_message_iter_init_append (message, &iter); 1419 if (!dbus_message_iter_append_basic (&iter, DBUS_TYPE_STRING, &errmsg)) 1420 goto out; 1421 1422 if (!bus_transaction_send_from_driver (transaction, pending->will_get_reply, 1423 message)) 1424 goto out; 1425 1426 retval = TRUE; 1427 1428 out: 1429 dbus_message_unref (message); 1430 return retval; 1431 } 1432 1433 static dbus_bool_t 1434 bus_pending_reply_expired (BusExpireList *list, 1435 DBusList *link, 1436 void *data) 1437 { 1438 BusPendingReply *pending = link->data; 1439 BusConnections *connections = data; 1440 BusTransaction *transaction; 1441 1442 /* No reply is forthcoming. So nuke it if we can. If not, 1443 * leave it in the list to try expiring again later when we 1444 * get more memory. 1445 */ 1446 1447 _dbus_verbose ("Expiring pending reply %p, replier %p receiver %p serial %u\n", 1448 pending, 1449 pending->will_send_reply, 1450 pending->will_get_reply, 1451 pending->reply_serial); 1452 1453 transaction = bus_transaction_new (connections->context); 1454 if (transaction == NULL) 1455 return FALSE; 1456 1457 if (!bus_pending_reply_send_no_reply (connections, 1458 transaction, 1459 pending)) 1460 { 1461 bus_transaction_cancel_and_free (transaction); 1462 return FALSE; 1463 } 1464 1465 _dbus_list_remove_link (&connections->pending_replies->items, 1466 link); 1467 bus_pending_reply_free (pending); 1468 bus_transaction_execute_and_free (transaction); 1469 1470 return TRUE; 1471 } 1472 1473 static void 1474 bus_connection_drop_pending_replies (BusConnections *connections, 1475 DBusConnection *connection) 1476 { 1477 /* The DBusConnection is almost 100% finalized here, so you can't 1478 * do anything with it except check for pointer equality 1479 */ 1480 DBusList *link; 1481 1482 _dbus_verbose ("Dropping pending replies that involve connection %p\n", 1483 connection); 1484 1485 link = _dbus_list_get_first_link (&connections->pending_replies->items); 1486 while (link != NULL) 1487 { 1488 DBusList *next; 1489 BusPendingReply *pending; 1490 1491 next = _dbus_list_get_next_link (&connections->pending_replies->items, 1492 link); 1493 pending = link->data; 1494 1495 if (pending->will_get_reply == connection) 1496 { 1497 /* We don't need to track this pending reply anymore */ 1498 1499 _dbus_verbose ("Dropping pending reply %p, replier %p receiver %p serial %u\n", 1500 pending, 1501 pending->will_send_reply, 1502 pending->will_get_reply, 1503 pending->reply_serial); 1504 1505 _dbus_list_remove_link (&connections->pending_replies->items, 1506 link); 1507 bus_pending_reply_free (pending); 1508 } 1509 else if (pending->will_send_reply == connection) 1510 { 1511 /* The reply isn't going to be sent, so set things 1512 * up so it will be expired right away 1513 */ 1514 _dbus_verbose ("Will expire pending reply %p, replier %p receiver %p serial %u\n", 1515 pending, 1516 pending->will_send_reply, 1517 pending->will_get_reply, 1518 pending->reply_serial); 1519 1520 pending->will_send_reply = NULL; 1521 pending->expire_item.added_tv_sec = 0; 1522 pending->expire_item.added_tv_usec = 0; 1523 1524 bus_expire_timeout_set_interval (connections->pending_replies->timeout, 1525 0); 1526 } 1527 1528 link = next; 1529 } 1530 } 1531 1532 1533 typedef struct 1534 { 1535 BusPendingReply *pending; 1536 BusConnections *connections; 1537 } CancelPendingReplyData; 1538 1539 static void 1540 cancel_pending_reply (void *data) 1541 { 1542 CancelPendingReplyData *d = data; 1543 1544 _dbus_verbose ("%s: d = %p\n", _DBUS_FUNCTION_NAME, d); 1545 1546 if (!_dbus_list_remove (&d->connections->pending_replies->items, 1547 d->pending)) 1548 _dbus_assert_not_reached ("pending reply did not exist to be cancelled"); 1549 1550 bus_pending_reply_free (d->pending); /* since it's been cancelled */ 1551 } 1552 1553 static void 1554 cancel_pending_reply_data_free (void *data) 1555 { 1556 CancelPendingReplyData *d = data; 1557 1558 _dbus_verbose ("%s: d = %p\n", _DBUS_FUNCTION_NAME, d); 1559 1560 /* d->pending should be either freed or still 1561 * in the list of pending replies (owned by someone 1562 * else) 1563 */ 1564 1565 dbus_free (d); 1566 } 1567 1568 /* 1569 * Record that a reply is allowed; return TRUE on success. 1570 */ 1571 dbus_bool_t 1572 bus_connections_expect_reply (BusConnections *connections, 1573 BusTransaction *transaction, 1574 DBusConnection *will_get_reply, 1575 DBusConnection *will_send_reply, 1576 DBusMessage *reply_to_this, 1577 DBusError *error) 1578 { 1579 BusPendingReply *pending; 1580 dbus_uint32_t reply_serial; 1581 DBusList *link; 1582 CancelPendingReplyData *cprd; 1583 int count; 1584 1585 _dbus_assert (will_get_reply != NULL); 1586 _dbus_assert (will_send_reply != NULL); 1587 _dbus_assert (reply_to_this != NULL); 1588 1589 if (dbus_message_get_no_reply (reply_to_this)) 1590 return TRUE; /* we won't allow a reply, since client doesn't care for one. */ 1591 1592 reply_serial = dbus_message_get_serial (reply_to_this); 1593 1594 link = _dbus_list_get_first_link (&connections->pending_replies->items); 1595 count = 0; 1596 while (link != NULL) 1597 { 1598 pending = link->data; 1599 1600 if (pending->reply_serial == reply_serial && 1601 pending->will_get_reply == will_get_reply && 1602 pending->will_send_reply == will_send_reply) 1603 { 1604 dbus_set_error (error, DBUS_ERROR_ACCESS_DENIED, 1605 "Message has the same reply serial as a currently-outstanding existing method call"); 1606 return FALSE; 1607 } 1608 1609 link = _dbus_list_get_next_link (&connections->pending_replies->items, 1610 link); 1611 if (pending->will_get_reply == will_get_reply) 1612 ++count; 1613 } 1614 1615 if (count >= 1616 bus_context_get_max_replies_per_connection (connections->context)) 1617 { 1618 dbus_set_error (error, DBUS_ERROR_LIMITS_EXCEEDED, 1619 "The maximum number of pending replies per connection has been reached"); 1620 return FALSE; 1621 } 1622 1623 pending = dbus_new0 (BusPendingReply, 1); 1624 if (pending == NULL) 1625 { 1626 BUS_SET_OOM (error); 1627 return FALSE; 1628 } 1629 1630 #ifdef DBUS_ENABLE_VERBOSE_MODE 1631 /* so we can see a not-yet-added pending reply */ 1632 pending->expire_item.added_tv_sec = 1; 1633 pending->expire_item.added_tv_usec = 1; 1634 #endif 1635 1636 pending->will_get_reply = will_get_reply; 1637 pending->will_send_reply = will_send_reply; 1638 pending->reply_serial = reply_serial; 1639 1640 cprd = dbus_new0 (CancelPendingReplyData, 1); 1641 if (cprd == NULL) 1642 { 1643 BUS_SET_OOM (error); 1644 bus_pending_reply_free (pending); 1645 return FALSE; 1646 } 1647 1648 if (!_dbus_list_prepend (&connections->pending_replies->items, 1649 pending)) 1650 { 1651 BUS_SET_OOM (error); 1652 dbus_free (cprd); 1653 bus_pending_reply_free (pending); 1654 return FALSE; 1655 } 1656 1657 if (!bus_transaction_add_cancel_hook (transaction, 1658 cancel_pending_reply, 1659 cprd, 1660 cancel_pending_reply_data_free)) 1661 { 1662 BUS_SET_OOM (error); 1663 _dbus_list_remove (&connections->pending_replies->items, pending); 1664 dbus_free (cprd); 1665 bus_pending_reply_free (pending); 1666 return FALSE; 1667 } 1668 1669 cprd->pending = pending; 1670 cprd->connections = connections; 1671 1672 _dbus_get_current_time (&pending->expire_item.added_tv_sec, 1673 &pending->expire_item.added_tv_usec); 1674 1675 _dbus_verbose ("Added pending reply %p, replier %p receiver %p serial %u\n", 1676 pending, 1677 pending->will_send_reply, 1678 pending->will_get_reply, 1679 pending->reply_serial); 1680 1681 return TRUE; 1682 } 1683 1684 typedef struct 1685 { 1686 DBusList *link; 1687 BusConnections *connections; 1688 } CheckPendingReplyData; 1689 1690 static void 1691 cancel_check_pending_reply (void *data) 1692 { 1693 CheckPendingReplyData *d = data; 1694 1695 _dbus_verbose ("%s: d = %p\n", _DBUS_FUNCTION_NAME, d); 1696 1697 _dbus_list_prepend_link (&d->connections->pending_replies->items, 1698 d->link); 1699 d->link = NULL; 1700 } 1701 1702 static void 1703 check_pending_reply_data_free (void *data) 1704 { 1705 CheckPendingReplyData *d = data; 1706 1707 _dbus_verbose ("%s: d = %p\n", _DBUS_FUNCTION_NAME, d); 1708 1709 if (d->link != NULL) 1710 { 1711 BusPendingReply *pending = d->link->data; 1712 1713 _dbus_assert (_dbus_list_find_last (&d->connections->pending_replies->items, 1714 pending) == NULL); 1715 1716 bus_pending_reply_free (pending); 1717 _dbus_list_free_link (d->link); 1718 } 1719 1720 dbus_free (d); 1721 } 1722 1723 /* 1724 * Check whether a reply is allowed, remove BusPendingReply 1725 * if so, return TRUE if so. 1726 */ 1727 dbus_bool_t 1728 bus_connections_check_reply (BusConnections *connections, 1729 BusTransaction *transaction, 1730 DBusConnection *sending_reply, 1731 DBusConnection *receiving_reply, 1732 DBusMessage *reply, 1733 DBusError *error) 1734 { 1735 CheckPendingReplyData *cprd; 1736 DBusList *link; 1737 dbus_uint32_t reply_serial; 1738 1739 _dbus_assert (sending_reply != NULL); 1740 _dbus_assert (receiving_reply != NULL); 1741 1742 reply_serial = dbus_message_get_reply_serial (reply); 1743 1744 link = _dbus_list_get_first_link (&connections->pending_replies->items); 1745 while (link != NULL) 1746 { 1747 BusPendingReply *pending = link->data; 1748 1749 if (pending->reply_serial == reply_serial && 1750 pending->will_get_reply == receiving_reply && 1751 pending->will_send_reply == sending_reply) 1752 { 1753 _dbus_verbose ("Found pending reply with serial %u\n", reply_serial); 1754 break; 1755 } 1756 1757 link = _dbus_list_get_next_link (&connections->pending_replies->items, 1758 link); 1759 } 1760 1761 if (link == NULL) 1762 { 1763 _dbus_verbose ("No pending reply expected\n"); 1764 1765 return FALSE; 1766 } 1767 1768 cprd = dbus_new0 (CheckPendingReplyData, 1); 1769 if (cprd == NULL) 1770 { 1771 BUS_SET_OOM (error); 1772 return FALSE; 1773 } 1774 1775 if (!bus_transaction_add_cancel_hook (transaction, 1776 cancel_check_pending_reply, 1777 cprd, 1778 check_pending_reply_data_free)) 1779 { 1780 BUS_SET_OOM (error); 1781 dbus_free (cprd); 1782 return FALSE; 1783 } 1784 1785 cprd->link = link; 1786 cprd->connections = connections; 1787 1788 _dbus_list_unlink (&connections->pending_replies->items, 1789 link); 1790 1791 _dbus_assert (_dbus_list_find_last (&connections->pending_replies->items, 1792 link->data) == NULL); 1793 1794 return TRUE; 1795 } 1796 1797 /* 1798 * Transactions 1799 * 1800 * Note that this is fairly fragile; in particular, don't try to use 1801 * one transaction across any main loop iterations. 1802 */ 1803 1804 typedef struct 1805 { 1806 BusTransaction *transaction; 1807 DBusMessage *message; 1808 DBusPreallocatedSend *preallocated; 1809 } MessageToSend; 1810 1811 typedef struct 1812 { 1813 BusTransactionCancelFunction cancel_function; 1814 DBusFreeFunction free_data_function; 1815 void *data; 1816 } CancelHook; 1817 1818 struct BusTransaction 1819 { 1820 DBusList *connections; 1821 BusContext *context; 1822 DBusList *cancel_hooks; 1823 }; 1824 1825 static void 1826 message_to_send_free (DBusConnection *connection, 1827 MessageToSend *to_send) 1828 { 1829 if (to_send->message) 1830 dbus_message_unref (to_send->message); 1831 1832 if (to_send->preallocated) 1833 dbus_connection_free_preallocated_send (connection, to_send->preallocated); 1834 1835 dbus_free (to_send); 1836 } 1837 1838 static void 1839 cancel_hook_cancel (void *element, 1840 void *data) 1841 { 1842 CancelHook *ch = element; 1843 1844 _dbus_verbose ("Running transaction cancel hook\n"); 1845 1846 if (ch->cancel_function) 1847 (* ch->cancel_function) (ch->data); 1848 } 1849 1850 static void 1851 cancel_hook_free (void *element, 1852 void *data) 1853 { 1854 CancelHook *ch = element; 1855 1856 if (ch->free_data_function) 1857 (* ch->free_data_function) (ch->data); 1858 1859 dbus_free (ch); 1860 } 1861 1862 static void 1863 free_cancel_hooks (BusTransaction *transaction) 1864 { 1865 _dbus_list_foreach (&transaction->cancel_hooks, 1866 cancel_hook_free, NULL); 1867 1868 _dbus_list_clear (&transaction->cancel_hooks); 1869 } 1870 1871 BusTransaction* 1872 bus_transaction_new (BusContext *context) 1873 { 1874 BusTransaction *transaction; 1875 1876 transaction = dbus_new0 (BusTransaction, 1); 1877 if (transaction == NULL) 1878 return NULL; 1879 1880 transaction->context = context; 1881 1882 return transaction; 1883 } 1884 1885 BusContext* 1886 bus_transaction_get_context (BusTransaction *transaction) 1887 { 1888 return transaction->context; 1889 } 1890 1891 BusConnections* 1892 bus_transaction_get_connections (BusTransaction *transaction) 1893 { 1894 return bus_context_get_connections (transaction->context); 1895 } 1896 1897 dbus_bool_t 1898 bus_transaction_send_from_driver (BusTransaction *transaction, 1899 DBusConnection *connection, 1900 DBusMessage *message) 1901 { 1902 /* We have to set the sender to the driver, and have 1903 * to check security policy since it was not done in 1904 * dispatch.c 1905 */ 1906 _dbus_verbose ("Sending %s %s %s from driver\n", 1907 dbus_message_get_interface (message) ? 1908 dbus_message_get_interface (message) : "(no interface)", 1909 dbus_message_get_member (message) ? 1910 dbus_message_get_member (message) : "(no member)", 1911 dbus_message_get_error_name (message) ? 1912 dbus_message_get_error_name (message) : "(no error name)"); 1913 1914 if (!dbus_message_set_sender (message, DBUS_SERVICE_DBUS)) 1915 return FALSE; 1916 1917 if (bus_connection_is_active (connection)) 1918 { 1919 if (!dbus_message_set_destination (message, 1920 bus_connection_get_name (connection))) 1921 return FALSE; 1922 } 1923 1924 /* bus driver never wants a reply */ 1925 dbus_message_set_no_reply (message, TRUE); 1926 1927 /* If security policy doesn't allow the message, we silently 1928 * eat it; the driver doesn't care about getting a reply. 1929 */ 1930 if (!bus_context_check_security_policy (bus_transaction_get_context (transaction), 1931 transaction, 1932 NULL, connection, connection, message, NULL)) 1933 return TRUE; 1934 1935 return bus_transaction_send (transaction, connection, message); 1936 } 1937 1938 dbus_bool_t 1939 bus_transaction_send (BusTransaction *transaction, 1940 DBusConnection *connection, 1941 DBusMessage *message) 1942 { 1943 MessageToSend *to_send; 1944 BusConnectionData *d; 1945 DBusList *link; 1946 1947 _dbus_verbose (" trying to add %s interface=%s member=%s error=%s to transaction%s\n", 1948 dbus_message_get_type (message) == DBUS_MESSAGE_TYPE_ERROR ? "error" : 1949 dbus_message_get_reply_serial (message) != 0 ? "reply" : 1950 "message", 1951 dbus_message_get_interface (message) ? 1952 dbus_message_get_interface (message) : "(unset)", 1953 dbus_message_get_member (message) ? 1954 dbus_message_get_member (message) : "(unset)", 1955 dbus_message_get_error_name (message) ? 1956 dbus_message_get_error_name (message) : "(unset)", 1957 dbus_connection_get_is_connected (connection) ? 1958 "" : " (disconnected)"); 1959 1960 _dbus_assert (dbus_message_get_sender (message) != NULL); 1961 1962 if (!dbus_connection_get_is_connected (connection)) 1963 return TRUE; /* silently ignore disconnected connections */ 1964 1965 d = BUS_CONNECTION_DATA (connection); 1966 _dbus_assert (d != NULL); 1967 1968 to_send = dbus_new (MessageToSend, 1); 1969 if (to_send == NULL) 1970 { 1971 return FALSE; 1972 } 1973 1974 to_send->preallocated = dbus_connection_preallocate_send (connection); 1975 if (to_send->preallocated == NULL) 1976 { 1977 dbus_free (to_send); 1978 return FALSE; 1979 } 1980 1981 dbus_message_ref (message); 1982 to_send->message = message; 1983 to_send->transaction = transaction; 1984 1985 _dbus_verbose ("about to prepend message\n"); 1986 1987 if (!_dbus_list_prepend (&d->transaction_messages, to_send)) 1988 { 1989 message_to_send_free (connection, to_send); 1990 return FALSE; 1991 } 1992 1993 _dbus_verbose ("prepended message\n"); 1994 1995 /* See if we already had this connection in the list 1996 * for this transaction. If we have a pending message, 1997 * then we should already be in transaction->connections 1998 */ 1999 link = _dbus_list_get_first_link (&d->transaction_messages); 2000 _dbus_assert (link->data == to_send); 2001 link = _dbus_list_get_next_link (&d->transaction_messages, link); 2002 while (link != NULL) 2003 { 2004 MessageToSend *m = link->data; 2005 DBusList *next = _dbus_list_get_next_link (&d->transaction_messages, link); 2006 2007 if (m->transaction == transaction) 2008 break; 2009 2010 link = next; 2011 } 2012 2013 if (link == NULL) 2014 { 2015 if (!_dbus_list_prepend (&transaction->connections, connection)) 2016 { 2017 _dbus_list_remove (&d->transaction_messages, to_send); 2018 message_to_send_free (connection, to_send); 2019 return FALSE; 2020 } 2021 } 2022 2023 return TRUE; 2024 } 2025 2026 static void 2027 connection_cancel_transaction (DBusConnection *connection, 2028 BusTransaction *transaction) 2029 { 2030 DBusList *link; 2031 BusConnectionData *d; 2032 2033 d = BUS_CONNECTION_DATA (connection); 2034 _dbus_assert (d != NULL); 2035 2036 link = _dbus_list_get_first_link (&d->transaction_messages); 2037 while (link != NULL) 2038 { 2039 MessageToSend *m = link->data; 2040 DBusList *next = _dbus_list_get_next_link (&d->transaction_messages, link); 2041 2042 if (m->transaction == transaction) 2043 { 2044 _dbus_list_remove_link (&d->transaction_messages, 2045 link); 2046 2047 message_to_send_free (connection, m); 2048 } 2049 2050 link = next; 2051 } 2052 } 2053 2054 void 2055 bus_transaction_cancel_and_free (BusTransaction *transaction) 2056 { 2057 DBusConnection *connection; 2058 2059 _dbus_verbose ("TRANSACTION: cancelled\n"); 2060 2061 while ((connection = _dbus_list_pop_first (&transaction->connections))) 2062 connection_cancel_transaction (connection, transaction); 2063 2064 _dbus_assert (transaction->connections == NULL); 2065 2066 _dbus_list_foreach (&transaction->cancel_hooks, 2067 cancel_hook_cancel, NULL); 2068 2069 free_cancel_hooks (transaction); 2070 2071 dbus_free (transaction); 2072 } 2073 2074 static void 2075 connection_execute_transaction (DBusConnection *connection, 2076 BusTransaction *transaction) 2077 { 2078 DBusList *link; 2079 BusConnectionData *d; 2080 2081 d = BUS_CONNECTION_DATA (connection); 2082 _dbus_assert (d != NULL); 2083 2084 /* Send the queue in order (FIFO) */ 2085 link = _dbus_list_get_last_link (&d->transaction_messages); 2086 while (link != NULL) 2087 { 2088 MessageToSend *m = link->data; 2089 DBusList *prev = _dbus_list_get_prev_link (&d->transaction_messages, link); 2090 2091 if (m->transaction == transaction) 2092 { 2093 _dbus_list_remove_link (&d->transaction_messages, 2094 link); 2095 2096 _dbus_assert (dbus_message_get_sender (m->message) != NULL); 2097 2098 dbus_connection_send_preallocated (connection, 2099 m->preallocated, 2100 m->message, 2101 NULL); 2102 2103 m->preallocated = NULL; /* so we don't double-free it */ 2104 2105 message_to_send_free (connection, m); 2106 } 2107 2108 link = prev; 2109 } 2110 } 2111 2112 void 2113 bus_transaction_execute_and_free (BusTransaction *transaction) 2114 { 2115 /* For each connection in transaction->connections 2116 * send the messages 2117 */ 2118 DBusConnection *connection; 2119 2120 _dbus_verbose ("TRANSACTION: executing\n"); 2121 2122 while ((connection = _dbus_list_pop_first (&transaction->connections))) 2123 connection_execute_transaction (connection, transaction); 2124 2125 _dbus_assert (transaction->connections == NULL); 2126 2127 free_cancel_hooks (transaction); 2128 2129 dbus_free (transaction); 2130 } 2131 2132 static void 2133 bus_connection_remove_transactions (DBusConnection *connection) 2134 { 2135 MessageToSend *to_send; 2136 BusConnectionData *d; 2137 2138 d = BUS_CONNECTION_DATA (connection); 2139 _dbus_assert (d != NULL); 2140 2141 while ((to_send = _dbus_list_get_first (&d->transaction_messages))) 2142 { 2143 /* only has an effect for the first MessageToSend listing this transaction */ 2144 _dbus_list_remove (&to_send->transaction->connections, 2145 connection); 2146 2147 _dbus_list_remove (&d->transaction_messages, to_send); 2148 message_to_send_free (connection, to_send); 2149 } 2150 } 2151 2152 /** 2153 * Converts the DBusError to a message reply 2154 */ 2155 dbus_bool_t 2156 bus_transaction_send_error_reply (BusTransaction *transaction, 2157 DBusConnection *connection, 2158 const DBusError *error, 2159 DBusMessage *in_reply_to) 2160 { 2161 DBusMessage *reply; 2162 2163 _dbus_assert (error != NULL); 2164 _DBUS_ASSERT_ERROR_IS_SET (error); 2165 2166 _dbus_verbose ("Sending error reply %s \"%s\"\n", 2167 error->name, error->message); 2168 2169 reply = dbus_message_new_error (in_reply_to, 2170 error->name, 2171 error->message); 2172 if (reply == NULL) 2173 return FALSE; 2174 2175 if (!bus_transaction_send_from_driver (transaction, connection, reply)) 2176 { 2177 dbus_message_unref (reply); 2178 return FALSE; 2179 } 2180 2181 dbus_message_unref (reply); 2182 2183 return TRUE; 2184 } 2185 2186 dbus_bool_t 2187 bus_transaction_add_cancel_hook (BusTransaction *transaction, 2188 BusTransactionCancelFunction cancel_function, 2189 void *data, 2190 DBusFreeFunction free_data_function) 2191 { 2192 CancelHook *ch; 2193 2194 ch = dbus_new (CancelHook, 1); 2195 if (ch == NULL) 2196 return FALSE; 2197 2198 _dbus_verbose (" adding cancel hook function = %p data = %p\n", 2199 cancel_function, data); 2200 2201 ch->cancel_function = cancel_function; 2202 ch->data = data; 2203 ch->free_data_function = free_data_function; 2204 2205 /* It's important that the hooks get run in reverse order that they 2206 * were added 2207 */ 2208 if (!_dbus_list_prepend (&transaction->cancel_hooks, ch)) 2209 { 2210 dbus_free (ch); 2211 return FALSE; 2212 } 2213 2214 return TRUE; 2215 } 2216