1 /* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */ 2 /* dbus-transport.c DBusTransport object (internal to D-Bus implementation) 3 * 4 * Copyright (C) 2002, 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 21 * 22 */ 23 24 #include <config.h> 25 #include "dbus-transport-protected.h" 26 #include "dbus-transport-unix.h" 27 #include "dbus-transport-socket.h" 28 #include "dbus-connection-internal.h" 29 #include "dbus-watch.h" 30 #include "dbus-auth.h" 31 #include "dbus-address.h" 32 #include "dbus-credentials.h" 33 #include "dbus-message-private.h" 34 #include "dbus-marshal-header.h" 35 #ifdef DBUS_BUILD_TESTS 36 #include "dbus-server-debug-pipe.h" 37 #endif 38 39 /** 40 * @defgroup DBusTransport DBusTransport object 41 * @ingroup DBusInternals 42 * @brief "Backend" for a DBusConnection. 43 * 44 * Types and functions related to DBusTransport. A transport is an 45 * abstraction that can send and receive data via various kinds of 46 * network connections or other IPC mechanisms. 47 * 48 * @{ 49 */ 50 51 /** 52 * @typedef DBusTransport 53 * 54 * Opaque object representing a way message stream. 55 * DBusTransport abstracts various kinds of actual 56 * transport mechanism, such as different network protocols, 57 * or encryption schemes. 58 */ 59 60 static void 61 live_messages_notify (DBusCounter *counter, 62 void *user_data) 63 { 64 DBusTransport *transport = user_data; 65 66 _dbus_transport_ref (transport); 67 68 #if 0 69 _dbus_verbose ("Size counter value is now %d\n", 70 (int) _dbus_counter_get_size_value (counter)); 71 _dbus_verbose ("Unix FD counter value is now %d\n", 72 (int) _dbus_counter_get_unix_fd_value (counter)); 73 #endif 74 75 /* disable or re-enable the read watch for the transport if 76 * required. 77 */ 78 if (transport->vtable->live_messages_changed) 79 (* transport->vtable->live_messages_changed) (transport); 80 81 _dbus_transport_unref (transport); 82 } 83 84 /** 85 * Initializes the base class members of DBusTransport. Chained up to 86 * by subclasses in their constructor. The server GUID is the 87 * globally unique ID for the server creating this connection 88 * and will be #NULL for the client side of a connection. The GUID 89 * is in hex format. 90 * 91 * @param transport the transport being created. 92 * @param vtable the subclass vtable. 93 * @param server_guid non-#NULL if this transport is on the server side of a connection 94 * @param address the address of the transport 95 * @returns #TRUE on success. 96 */ 97 dbus_bool_t 98 _dbus_transport_init_base (DBusTransport *transport, 99 const DBusTransportVTable *vtable, 100 const DBusString *server_guid, 101 const DBusString *address) 102 { 103 DBusMessageLoader *loader; 104 DBusAuth *auth; 105 DBusCounter *counter; 106 char *address_copy; 107 DBusCredentials *creds; 108 109 loader = _dbus_message_loader_new (); 110 if (loader == NULL) 111 return FALSE; 112 113 if (server_guid) 114 auth = _dbus_auth_server_new (server_guid); 115 else 116 auth = _dbus_auth_client_new (); 117 if (auth == NULL) 118 { 119 _dbus_message_loader_unref (loader); 120 return FALSE; 121 } 122 123 counter = _dbus_counter_new (); 124 if (counter == NULL) 125 { 126 _dbus_auth_unref (auth); 127 _dbus_message_loader_unref (loader); 128 return FALSE; 129 } 130 131 creds = _dbus_credentials_new (); 132 if (creds == NULL) 133 { 134 _dbus_counter_unref (counter); 135 _dbus_auth_unref (auth); 136 _dbus_message_loader_unref (loader); 137 return FALSE; 138 } 139 140 if (server_guid) 141 { 142 _dbus_assert (address == NULL); 143 address_copy = NULL; 144 } 145 else 146 { 147 _dbus_assert (address != NULL); 148 149 if (!_dbus_string_copy_data (address, &address_copy)) 150 { 151 _dbus_credentials_unref (creds); 152 _dbus_counter_unref (counter); 153 _dbus_auth_unref (auth); 154 _dbus_message_loader_unref (loader); 155 return FALSE; 156 } 157 } 158 159 transport->refcount = 1; 160 transport->vtable = vtable; 161 transport->loader = loader; 162 transport->auth = auth; 163 transport->live_messages = counter; 164 transport->authenticated = FALSE; 165 transport->disconnected = FALSE; 166 transport->is_server = (server_guid != NULL); 167 transport->send_credentials_pending = !transport->is_server; 168 transport->receive_credentials_pending = transport->is_server; 169 transport->address = address_copy; 170 171 transport->unix_user_function = NULL; 172 transport->unix_user_data = NULL; 173 transport->free_unix_user_data = NULL; 174 175 transport->windows_user_function = NULL; 176 transport->windows_user_data = NULL; 177 transport->free_windows_user_data = NULL; 178 179 transport->expected_guid = NULL; 180 181 /* Try to default to something that won't totally hose the system, 182 * but doesn't impose too much of a limitation. 183 */ 184 transport->max_live_messages_size = _DBUS_ONE_MEGABYTE * 63; 185 186 /* On Linux RLIMIT_NOFILE defaults to 1024, so allowing 4096 fds live 187 should be more than enough */ 188 transport->max_live_messages_unix_fds = 4096; 189 190 /* credentials read from socket if any */ 191 transport->credentials = creds; 192 193 _dbus_counter_set_notify (transport->live_messages, 194 transport->max_live_messages_size, 195 transport->max_live_messages_unix_fds, 196 live_messages_notify, 197 transport); 198 199 if (transport->address) 200 _dbus_verbose ("Initialized transport on address %s\n", transport->address); 201 202 return TRUE; 203 } 204 205 /** 206 * Finalizes base class members of DBusTransport. 207 * Chained up to from subclass finalizers. 208 * 209 * @param transport the transport. 210 */ 211 void 212 _dbus_transport_finalize_base (DBusTransport *transport) 213 { 214 if (!transport->disconnected) 215 _dbus_transport_disconnect (transport); 216 217 if (transport->free_unix_user_data != NULL) 218 (* transport->free_unix_user_data) (transport->unix_user_data); 219 220 if (transport->free_windows_user_data != NULL) 221 (* transport->free_windows_user_data) (transport->windows_user_data); 222 223 _dbus_message_loader_unref (transport->loader); 224 _dbus_auth_unref (transport->auth); 225 _dbus_counter_set_notify (transport->live_messages, 226 0, 0, NULL, NULL); 227 _dbus_counter_unref (transport->live_messages); 228 dbus_free (transport->address); 229 dbus_free (transport->expected_guid); 230 if (transport->credentials) 231 _dbus_credentials_unref (transport->credentials); 232 } 233 234 235 /** 236 * Verifies if a given D-Bus address is a valid address 237 * by attempting to connect to it. If it is, returns the 238 * opened DBusTransport object. If it isn't, returns #NULL 239 * and sets @p error. 240 * 241 * @param error address where an error can be returned. 242 * @returns a new transport, or #NULL on failure. 243 */ 244 static DBusTransport* 245 check_address (const char *address, DBusError *error) 246 { 247 DBusAddressEntry **entries; 248 DBusTransport *transport = NULL; 249 int len, i; 250 251 _dbus_assert (address != NULL); 252 _dbus_assert (*address != '\0'); 253 254 if (!dbus_parse_address (address, &entries, &len, error)) 255 return NULL; /* not a valid address */ 256 257 for (i = 0; i < len; i++) 258 { 259 transport = _dbus_transport_open (entries[i], error); 260 if (transport != NULL) 261 break; 262 } 263 264 dbus_address_entries_free (entries); 265 return transport; 266 } 267 268 /** 269 * Creates a new transport for the "autostart" method. 270 * This creates a client-side of a transport. 271 * 272 * @param error address where an error can be returned. 273 * @returns a new transport, or #NULL on failure. 274 */ 275 static DBusTransport* 276 _dbus_transport_new_for_autolaunch (DBusError *error) 277 { 278 DBusString address; 279 DBusTransport *result = NULL; 280 281 _DBUS_ASSERT_ERROR_IS_CLEAR (error); 282 283 if (!_dbus_string_init (&address)) 284 { 285 dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL); 286 return NULL; 287 } 288 289 if (!_dbus_get_autolaunch_address (&address, error)) 290 { 291 _DBUS_ASSERT_ERROR_IS_SET (error); 292 goto out; 293 } 294 295 result = check_address (_dbus_string_get_const_data (&address), error); 296 if (result == NULL) 297 _DBUS_ASSERT_ERROR_IS_SET (error); 298 else 299 _DBUS_ASSERT_ERROR_IS_CLEAR (error); 300 301 out: 302 _dbus_string_free (&address); 303 return result; 304 } 305 306 static DBusTransportOpenResult 307 _dbus_transport_open_autolaunch (DBusAddressEntry *entry, 308 DBusTransport **transport_p, 309 DBusError *error) 310 { 311 const char *method; 312 313 method = dbus_address_entry_get_method (entry); 314 _dbus_assert (method != NULL); 315 316 if (strcmp (method, "autolaunch") == 0) 317 { 318 *transport_p = _dbus_transport_new_for_autolaunch (error); 319 320 if (*transport_p == NULL) 321 { 322 _DBUS_ASSERT_ERROR_IS_SET (error); 323 return DBUS_TRANSPORT_OPEN_DID_NOT_CONNECT; 324 } 325 else 326 { 327 _DBUS_ASSERT_ERROR_IS_CLEAR (error); 328 return DBUS_TRANSPORT_OPEN_OK; 329 } 330 } 331 else 332 { 333 _DBUS_ASSERT_ERROR_IS_CLEAR (error); 334 return DBUS_TRANSPORT_OPEN_NOT_HANDLED; 335 } 336 } 337 338 static const struct { 339 DBusTransportOpenResult (* func) (DBusAddressEntry *entry, 340 DBusTransport **transport_p, 341 DBusError *error); 342 } open_funcs[] = { 343 { _dbus_transport_open_socket }, 344 { _dbus_transport_open_platform_specific }, 345 { _dbus_transport_open_autolaunch } 346 #ifdef DBUS_BUILD_TESTS 347 , { _dbus_transport_open_debug_pipe } 348 #endif 349 }; 350 351 /** 352 * Try to open a new transport for the given address entry. (This 353 * opens a client-side-of-the-connection transport.) 354 * 355 * @param entry the address entry 356 * @param error location to store reason for failure. 357 * @returns new transport of #NULL on failure. 358 */ 359 DBusTransport* 360 _dbus_transport_open (DBusAddressEntry *entry, 361 DBusError *error) 362 { 363 DBusTransport *transport; 364 const char *expected_guid_orig; 365 char *expected_guid; 366 int i; 367 DBusError tmp_error = DBUS_ERROR_INIT; 368 369 _DBUS_ASSERT_ERROR_IS_CLEAR (error); 370 371 transport = NULL; 372 expected_guid_orig = dbus_address_entry_get_value (entry, "guid"); 373 expected_guid = _dbus_strdup (expected_guid_orig); 374 375 if (expected_guid_orig != NULL && expected_guid == NULL) 376 { 377 _DBUS_SET_OOM (error); 378 return NULL; 379 } 380 381 for (i = 0; i < (int) _DBUS_N_ELEMENTS (open_funcs); ++i) 382 { 383 DBusTransportOpenResult result; 384 385 _DBUS_ASSERT_ERROR_CONTENT_IS_CLEAR (&tmp_error); 386 result = (* open_funcs[i].func) (entry, &transport, &tmp_error); 387 388 switch (result) 389 { 390 case DBUS_TRANSPORT_OPEN_OK: 391 _DBUS_ASSERT_ERROR_CONTENT_IS_CLEAR (&tmp_error); 392 goto out; 393 break; 394 case DBUS_TRANSPORT_OPEN_NOT_HANDLED: 395 _DBUS_ASSERT_ERROR_CONTENT_IS_CLEAR (&tmp_error); 396 /* keep going through the loop of open funcs */ 397 break; 398 case DBUS_TRANSPORT_OPEN_BAD_ADDRESS: 399 _DBUS_ASSERT_ERROR_CONTENT_IS_SET (&tmp_error); 400 goto out; 401 break; 402 case DBUS_TRANSPORT_OPEN_DID_NOT_CONNECT: 403 _DBUS_ASSERT_ERROR_CONTENT_IS_SET (&tmp_error); 404 goto out; 405 break; 406 } 407 } 408 409 out: 410 411 if (transport == NULL) 412 { 413 if (!dbus_error_is_set (&tmp_error)) 414 _dbus_set_bad_address (&tmp_error, 415 NULL, NULL, 416 "Unknown address type (examples of valid types are \"tcp\" and on UNIX \"unix\")"); 417 418 _DBUS_ASSERT_ERROR_CONTENT_IS_SET (&tmp_error); 419 dbus_move_error(&tmp_error, error); 420 dbus_free (expected_guid); 421 } 422 else 423 { 424 _DBUS_ASSERT_ERROR_CONTENT_IS_CLEAR (&tmp_error); 425 426 /* In the case of autostart the initial guid is NULL 427 * and the autostart transport recursively calls 428 * _dbus_open_transport wich returns a transport 429 * with a guid. That guid is the definitive one. 430 * 431 * FIXME: if more transports are added they may have 432 * an effect on the expected_guid semantics (i.e. 433 * expected_guid and transport->expected_guid may 434 * both have values). This is very unlikely though 435 * we should either throw asserts here for those 436 * corner cases or refactor the code so it is 437 * clearer on what is expected and what is not 438 */ 439 if(expected_guid) 440 transport->expected_guid = expected_guid; 441 } 442 443 return transport; 444 } 445 446 /** 447 * Increments the reference count for the transport. 448 * 449 * @param transport the transport. 450 * @returns the transport. 451 */ 452 DBusTransport * 453 _dbus_transport_ref (DBusTransport *transport) 454 { 455 _dbus_assert (transport->refcount > 0); 456 457 transport->refcount += 1; 458 459 return transport; 460 } 461 462 /** 463 * Decrements the reference count for the transport. 464 * Disconnects and finalizes the transport if 465 * the reference count reaches zero. 466 * 467 * @param transport the transport. 468 */ 469 void 470 _dbus_transport_unref (DBusTransport *transport) 471 { 472 _dbus_assert (transport != NULL); 473 _dbus_assert (transport->refcount > 0); 474 475 transport->refcount -= 1; 476 if (transport->refcount == 0) 477 { 478 _dbus_verbose ("finalizing\n"); 479 480 _dbus_assert (transport->vtable->finalize != NULL); 481 482 (* transport->vtable->finalize) (transport); 483 } 484 } 485 486 /** 487 * Closes our end of the connection to a remote application. Further 488 * attempts to use this transport will fail. Only the first call to 489 * _dbus_transport_disconnect() will have an effect. 490 * 491 * @param transport the transport. 492 * 493 */ 494 void 495 _dbus_transport_disconnect (DBusTransport *transport) 496 { 497 _dbus_verbose ("start\n"); 498 499 _dbus_assert (transport->vtable->disconnect != NULL); 500 501 if (transport->disconnected) 502 return; 503 504 (* transport->vtable->disconnect) (transport); 505 506 transport->disconnected = TRUE; 507 508 _dbus_verbose ("end\n"); 509 } 510 511 /** 512 * Returns #TRUE if the transport has not been disconnected. 513 * Disconnection can result from _dbus_transport_disconnect() 514 * or because the server drops its end of the connection. 515 * 516 * @param transport the transport. 517 * @returns whether we're connected 518 */ 519 dbus_bool_t 520 _dbus_transport_get_is_connected (DBusTransport *transport) 521 { 522 return !transport->disconnected; 523 } 524 525 static dbus_bool_t 526 auth_via_unix_user_function (DBusTransport *transport) 527 { 528 DBusCredentials *auth_identity; 529 dbus_bool_t allow; 530 DBusConnection *connection; 531 DBusAllowUnixUserFunction unix_user_function; 532 void *unix_user_data; 533 dbus_uid_t uid; 534 535 /* Dropping the lock here probably isn't that safe. */ 536 537 auth_identity = _dbus_auth_get_identity (transport->auth); 538 _dbus_assert (auth_identity != NULL); 539 540 connection = transport->connection; 541 unix_user_function = transport->unix_user_function; 542 unix_user_data = transport->unix_user_data; 543 uid = _dbus_credentials_get_unix_uid (auth_identity); 544 545 _dbus_verbose ("unlock\n"); 546 _dbus_connection_unlock (connection); 547 548 allow = (* unix_user_function) (connection, 549 uid, 550 unix_user_data); 551 552 _dbus_verbose ("lock post unix user function\n"); 553 _dbus_connection_lock (connection); 554 555 if (allow) 556 { 557 _dbus_verbose ("Client UID "DBUS_UID_FORMAT" authorized\n", uid); 558 } 559 else 560 { 561 _dbus_verbose ("Client UID "DBUS_UID_FORMAT 562 " was rejected, disconnecting\n", 563 _dbus_credentials_get_unix_uid (auth_identity)); 564 _dbus_transport_disconnect (transport); 565 } 566 567 return allow; 568 } 569 570 static dbus_bool_t 571 auth_via_windows_user_function (DBusTransport *transport) 572 { 573 DBusCredentials *auth_identity; 574 dbus_bool_t allow; 575 DBusConnection *connection; 576 DBusAllowWindowsUserFunction windows_user_function; 577 void *windows_user_data; 578 char *windows_sid; 579 580 /* Dropping the lock here probably isn't that safe. */ 581 582 auth_identity = _dbus_auth_get_identity (transport->auth); 583 _dbus_assert (auth_identity != NULL); 584 585 connection = transport->connection; 586 windows_user_function = transport->windows_user_function; 587 windows_user_data = transport->unix_user_data; 588 windows_sid = _dbus_strdup (_dbus_credentials_get_windows_sid (auth_identity)); 589 590 if (windows_sid == NULL) 591 { 592 /* OOM */ 593 return FALSE; 594 } 595 596 _dbus_verbose ("unlock\n"); 597 _dbus_connection_unlock (connection); 598 599 allow = (* windows_user_function) (connection, 600 windows_sid, 601 windows_user_data); 602 603 _dbus_verbose ("lock post windows user function\n"); 604 _dbus_connection_lock (connection); 605 606 if (allow) 607 { 608 _dbus_verbose ("Client SID '%s' authorized\n", windows_sid); 609 } 610 else 611 { 612 _dbus_verbose ("Client SID '%s' was rejected, disconnecting\n", 613 _dbus_credentials_get_windows_sid (auth_identity)); 614 _dbus_transport_disconnect (transport); 615 } 616 617 return allow; 618 } 619 620 static dbus_bool_t 621 auth_via_default_rules (DBusTransport *transport) 622 { 623 DBusCredentials *auth_identity; 624 DBusCredentials *our_identity; 625 dbus_bool_t allow; 626 627 auth_identity = _dbus_auth_get_identity (transport->auth); 628 _dbus_assert (auth_identity != NULL); 629 630 /* By default, connection is allowed if the client is 1) root or 2) 631 * has the same UID as us or 3) anonymous is allowed. 632 */ 633 634 our_identity = _dbus_credentials_new_from_current_process (); 635 if (our_identity == NULL) 636 { 637 /* OOM */ 638 return FALSE; 639 } 640 641 if (transport->allow_anonymous || 642 _dbus_credentials_get_unix_uid (auth_identity) == 0 || 643 _dbus_credentials_same_user (our_identity, 644 auth_identity)) 645 { 646 if (_dbus_credentials_include(our_identity,DBUS_CREDENTIAL_WINDOWS_SID)) 647 _dbus_verbose ("Client authorized as SID '%s'" 648 "matching our SID '%s'\n", 649 _dbus_credentials_get_windows_sid(auth_identity), 650 _dbus_credentials_get_windows_sid(our_identity)); 651 else 652 _dbus_verbose ("Client authorized as UID "DBUS_UID_FORMAT 653 " matching our UID "DBUS_UID_FORMAT"\n", 654 _dbus_credentials_get_unix_uid(auth_identity), 655 _dbus_credentials_get_unix_uid(our_identity)); 656 /* We have authenticated! */ 657 allow = TRUE; 658 } 659 else 660 { 661 if (_dbus_credentials_include(our_identity,DBUS_CREDENTIAL_WINDOWS_SID)) 662 _dbus_verbose ("Client authorized as SID '%s'" 663 " but our SID is '%s', disconnecting\n", 664 (_dbus_credentials_get_windows_sid(auth_identity) ? 665 _dbus_credentials_get_windows_sid(auth_identity) : "<null>"), 666 (_dbus_credentials_get_windows_sid(our_identity) ? 667 _dbus_credentials_get_windows_sid(our_identity) : "<null>")); 668 else 669 _dbus_verbose ("Client authorized as UID "DBUS_UID_FORMAT 670 " but our UID is "DBUS_UID_FORMAT", disconnecting\n", 671 _dbus_credentials_get_unix_uid(auth_identity), 672 _dbus_credentials_get_unix_uid(our_identity)); 673 _dbus_transport_disconnect (transport); 674 allow = FALSE; 675 } 676 677 _dbus_credentials_unref (our_identity); 678 679 return allow; 680 } 681 682 683 /** 684 * Returns #TRUE if we have been authenticated. Will return #TRUE 685 * even if the transport is disconnected. 686 * 687 * @todo we drop connection->mutex when calling the unix_user_function, 688 * and windows_user_function, which may not be safe really. 689 * 690 * @param transport the transport 691 * @returns whether we're authenticated 692 */ 693 dbus_bool_t 694 _dbus_transport_get_is_authenticated (DBusTransport *transport) 695 { 696 if (transport->authenticated) 697 return TRUE; 698 else 699 { 700 dbus_bool_t maybe_authenticated; 701 702 if (transport->disconnected) 703 return FALSE; 704 705 /* paranoia ref since we call user callbacks sometimes */ 706 _dbus_connection_ref_unlocked (transport->connection); 707 708 maybe_authenticated = 709 (!(transport->send_credentials_pending || 710 transport->receive_credentials_pending)); 711 712 if (maybe_authenticated) 713 { 714 switch (_dbus_auth_do_work (transport->auth)) 715 { 716 case DBUS_AUTH_STATE_AUTHENTICATED: 717 /* leave as maybe_authenticated */ 718 break; 719 default: 720 maybe_authenticated = FALSE; 721 } 722 } 723 724 /* If we're the client, verify the GUID 725 */ 726 if (maybe_authenticated && !transport->is_server) 727 { 728 const char *server_guid; 729 730 server_guid = _dbus_auth_get_guid_from_server (transport->auth); 731 _dbus_assert (server_guid != NULL); 732 733 if (transport->expected_guid && 734 strcmp (transport->expected_guid, server_guid) != 0) 735 { 736 _dbus_verbose ("Client expected GUID '%s' and we got '%s' from the server\n", 737 transport->expected_guid, server_guid); 738 _dbus_transport_disconnect (transport); 739 _dbus_connection_unref_unlocked (transport->connection); 740 return FALSE; 741 } 742 743 if (transport->expected_guid == NULL) 744 { 745 transport->expected_guid = _dbus_strdup (server_guid); 746 747 if (transport->expected_guid == NULL) 748 { 749 _dbus_verbose ("No memory to complete auth\n"); 750 return FALSE; 751 } 752 } 753 } 754 755 /* If we're the server, see if we want to allow this identity to proceed. 756 */ 757 if (maybe_authenticated && transport->is_server) 758 { 759 dbus_bool_t allow; 760 DBusCredentials *auth_identity; 761 762 auth_identity = _dbus_auth_get_identity (transport->auth); 763 _dbus_assert (auth_identity != NULL); 764 765 /* If we have an auth'd user and a user function, delegate 766 * deciding whether auth credentials are good enough to the 767 * app; otherwise, use our default decision process. 768 */ 769 if (transport->unix_user_function != NULL && 770 _dbus_credentials_include (auth_identity, DBUS_CREDENTIAL_UNIX_USER_ID)) 771 { 772 allow = auth_via_unix_user_function (transport); 773 } 774 else if (transport->windows_user_function != NULL && 775 _dbus_credentials_include (auth_identity, DBUS_CREDENTIAL_WINDOWS_SID)) 776 { 777 allow = auth_via_windows_user_function (transport); 778 } 779 else 780 { 781 allow = auth_via_default_rules (transport); 782 } 783 784 if (!allow) 785 maybe_authenticated = FALSE; 786 } 787 788 transport->authenticated = maybe_authenticated; 789 790 _dbus_connection_unref_unlocked (transport->connection); 791 return maybe_authenticated; 792 } 793 } 794 795 /** 796 * See dbus_connection_get_is_anonymous(). 797 * 798 * @param transport the transport 799 * @returns #TRUE if not authenticated or authenticated as anonymous 800 */ 801 dbus_bool_t 802 _dbus_transport_get_is_anonymous (DBusTransport *transport) 803 { 804 DBusCredentials *auth_identity; 805 806 if (!transport->authenticated) 807 return TRUE; 808 809 auth_identity = _dbus_auth_get_identity (transport->auth); 810 811 if (_dbus_credentials_are_anonymous (auth_identity)) 812 return TRUE; 813 else 814 return FALSE; 815 } 816 817 /** 818 * Returns TRUE if the transport supports sending unix fds. 819 * 820 * @param transport the transport 821 * @returns #TRUE if TRUE it is possible to send unix fds across the transport. 822 */ 823 dbus_bool_t 824 _dbus_transport_can_pass_unix_fd(DBusTransport *transport) 825 { 826 return DBUS_TRANSPORT_CAN_SEND_UNIX_FD(transport); 827 } 828 829 /** 830 * Gets the address of a transport. It will be 831 * #NULL for a server-side transport. 832 * 833 * @param transport the transport 834 * @returns transport's address 835 */ 836 const char* 837 _dbus_transport_get_address (DBusTransport *transport) 838 { 839 return transport->address; 840 } 841 842 /** 843 * Gets the id of the server we are connected to (see 844 * dbus_server_get_id()). Only works on client side. 845 * 846 * @param transport the transport 847 * @returns transport's server's id or #NULL if we are the server side 848 */ 849 const char* 850 _dbus_transport_get_server_id (DBusTransport *transport) 851 { 852 if (transport->is_server) 853 return NULL; 854 else 855 return transport->expected_guid; 856 } 857 858 /** 859 * Handles a watch by reading data, writing data, or disconnecting 860 * the transport, as appropriate for the given condition. 861 * 862 * @param transport the transport. 863 * @param watch the watch. 864 * @param condition the current state of the watched file descriptor. 865 * @returns #FALSE if not enough memory to fully handle the watch 866 */ 867 dbus_bool_t 868 _dbus_transport_handle_watch (DBusTransport *transport, 869 DBusWatch *watch, 870 unsigned int condition) 871 { 872 dbus_bool_t retval; 873 874 _dbus_assert (transport->vtable->handle_watch != NULL); 875 876 if (transport->disconnected) 877 return TRUE; 878 879 if (dbus_watch_get_socket (watch) < 0) 880 { 881 _dbus_warn_check_failed ("Tried to handle an invalidated watch; this watch should have been removed\n"); 882 return TRUE; 883 } 884 885 _dbus_watch_sanitize_condition (watch, &condition); 886 887 _dbus_transport_ref (transport); 888 _dbus_watch_ref (watch); 889 retval = (* transport->vtable->handle_watch) (transport, watch, condition); 890 _dbus_watch_unref (watch); 891 _dbus_transport_unref (transport); 892 893 return retval; 894 } 895 896 /** 897 * Sets the connection using this transport. Allows the transport 898 * to add watches to the connection, queue incoming messages, 899 * and pull outgoing messages. 900 * 901 * @param transport the transport. 902 * @param connection the connection. 903 * @returns #FALSE if not enough memory 904 */ 905 dbus_bool_t 906 _dbus_transport_set_connection (DBusTransport *transport, 907 DBusConnection *connection) 908 { 909 _dbus_assert (transport->vtable->connection_set != NULL); 910 _dbus_assert (transport->connection == NULL); 911 912 transport->connection = connection; 913 914 _dbus_transport_ref (transport); 915 if (!(* transport->vtable->connection_set) (transport)) 916 transport->connection = NULL; 917 _dbus_transport_unref (transport); 918 919 return transport->connection != NULL; 920 } 921 922 /** 923 * Get the socket file descriptor, if any. 924 * 925 * @param transport the transport 926 * @param fd_p pointer to fill in with the descriptor 927 * @returns #TRUE if a descriptor was available 928 */ 929 dbus_bool_t 930 _dbus_transport_get_socket_fd (DBusTransport *transport, 931 int *fd_p) 932 { 933 dbus_bool_t retval; 934 935 if (transport->vtable->get_socket_fd == NULL) 936 return FALSE; 937 938 if (transport->disconnected) 939 return FALSE; 940 941 _dbus_transport_ref (transport); 942 943 retval = (* transport->vtable->get_socket_fd) (transport, 944 fd_p); 945 946 _dbus_transport_unref (transport); 947 948 return retval; 949 } 950 951 /** 952 * Performs a single poll()/select() on the transport's file 953 * descriptors and then reads/writes data as appropriate, 954 * queueing incoming messages and sending outgoing messages. 955 * This is the backend for _dbus_connection_do_iteration(). 956 * See _dbus_connection_do_iteration() for full details. 957 * 958 * @param transport the transport. 959 * @param flags indicates whether to read or write, and whether to block. 960 * @param timeout_milliseconds if blocking, timeout or -1 for no timeout. 961 */ 962 void 963 _dbus_transport_do_iteration (DBusTransport *transport, 964 unsigned int flags, 965 int timeout_milliseconds) 966 { 967 _dbus_assert (transport->vtable->do_iteration != NULL); 968 969 _dbus_verbose ("Transport iteration flags 0x%x timeout %d connected = %d\n", 970 flags, timeout_milliseconds, !transport->disconnected); 971 972 if ((flags & (DBUS_ITERATION_DO_WRITING | 973 DBUS_ITERATION_DO_READING)) == 0) 974 return; /* Nothing to do */ 975 976 if (transport->disconnected) 977 return; 978 979 _dbus_transport_ref (transport); 980 (* transport->vtable->do_iteration) (transport, flags, 981 timeout_milliseconds); 982 _dbus_transport_unref (transport); 983 984 _dbus_verbose ("end\n"); 985 } 986 987 static dbus_bool_t 988 recover_unused_bytes (DBusTransport *transport) 989 { 990 if (_dbus_auth_needs_decoding (transport->auth)) 991 { 992 DBusString plaintext; 993 const DBusString *encoded; 994 DBusString *buffer; 995 int orig_len; 996 997 if (!_dbus_string_init (&plaintext)) 998 goto nomem; 999 1000 _dbus_auth_get_unused_bytes (transport->auth, 1001 &encoded); 1002 1003 if (!_dbus_auth_decode_data (transport->auth, 1004 encoded, &plaintext)) 1005 { 1006 _dbus_string_free (&plaintext); 1007 goto nomem; 1008 } 1009 1010 _dbus_message_loader_get_buffer (transport->loader, 1011 &buffer); 1012 1013 orig_len = _dbus_string_get_length (buffer); 1014 1015 if (!_dbus_string_move (&plaintext, 0, buffer, 1016 orig_len)) 1017 { 1018 _dbus_string_free (&plaintext); 1019 goto nomem; 1020 } 1021 1022 _dbus_verbose (" %d unused bytes sent to message loader\n", 1023 _dbus_string_get_length (buffer) - 1024 orig_len); 1025 1026 _dbus_message_loader_return_buffer (transport->loader, 1027 buffer, 1028 _dbus_string_get_length (buffer) - 1029 orig_len); 1030 1031 _dbus_auth_delete_unused_bytes (transport->auth); 1032 1033 _dbus_string_free (&plaintext); 1034 } 1035 else 1036 { 1037 const DBusString *bytes; 1038 DBusString *buffer; 1039 int orig_len; 1040 dbus_bool_t succeeded; 1041 1042 _dbus_message_loader_get_buffer (transport->loader, 1043 &buffer); 1044 1045 orig_len = _dbus_string_get_length (buffer); 1046 1047 _dbus_auth_get_unused_bytes (transport->auth, 1048 &bytes); 1049 1050 succeeded = TRUE; 1051 if (!_dbus_string_copy (bytes, 0, buffer, _dbus_string_get_length (buffer))) 1052 succeeded = FALSE; 1053 1054 _dbus_verbose (" %d unused bytes sent to message loader\n", 1055 _dbus_string_get_length (buffer) - 1056 orig_len); 1057 1058 _dbus_message_loader_return_buffer (transport->loader, 1059 buffer, 1060 _dbus_string_get_length (buffer) - 1061 orig_len); 1062 1063 if (succeeded) 1064 _dbus_auth_delete_unused_bytes (transport->auth); 1065 else 1066 goto nomem; 1067 } 1068 1069 return TRUE; 1070 1071 nomem: 1072 _dbus_verbose ("Not enough memory to transfer unused bytes from auth conversation\n"); 1073 return FALSE; 1074 } 1075 1076 /** 1077 * Reports our current dispatch status (whether there's buffered 1078 * data to be queued as messages, or not, or we need memory). 1079 * 1080 * @param transport the transport 1081 * @returns current status 1082 */ 1083 DBusDispatchStatus 1084 _dbus_transport_get_dispatch_status (DBusTransport *transport) 1085 { 1086 if (_dbus_counter_get_size_value (transport->live_messages) >= transport->max_live_messages_size || 1087 _dbus_counter_get_unix_fd_value (transport->live_messages) >= transport->max_live_messages_unix_fds) 1088 return DBUS_DISPATCH_COMPLETE; /* complete for now */ 1089 1090 if (!_dbus_transport_get_is_authenticated (transport)) 1091 { 1092 if (_dbus_auth_do_work (transport->auth) == 1093 DBUS_AUTH_STATE_WAITING_FOR_MEMORY) 1094 return DBUS_DISPATCH_NEED_MEMORY; 1095 else if (!_dbus_transport_get_is_authenticated (transport)) 1096 return DBUS_DISPATCH_COMPLETE; 1097 } 1098 1099 if (!transport->unused_bytes_recovered && 1100 !recover_unused_bytes (transport)) 1101 return DBUS_DISPATCH_NEED_MEMORY; 1102 1103 transport->unused_bytes_recovered = TRUE; 1104 1105 if (!_dbus_message_loader_queue_messages (transport->loader)) 1106 return DBUS_DISPATCH_NEED_MEMORY; 1107 1108 if (_dbus_message_loader_peek_message (transport->loader) != NULL) 1109 return DBUS_DISPATCH_DATA_REMAINS; 1110 else 1111 return DBUS_DISPATCH_COMPLETE; 1112 } 1113 1114 /** 1115 * Processes data we've read while handling a watch, potentially 1116 * converting some of it to messages and queueing those messages on 1117 * the connection. 1118 * 1119 * @param transport the transport 1120 * @returns #TRUE if we had enough memory to queue all messages 1121 */ 1122 dbus_bool_t 1123 _dbus_transport_queue_messages (DBusTransport *transport) 1124 { 1125 DBusDispatchStatus status; 1126 1127 #if 0 1128 _dbus_verbose ("_dbus_transport_queue_messages()\n"); 1129 #endif 1130 1131 /* Queue any messages */ 1132 while ((status = _dbus_transport_get_dispatch_status (transport)) == DBUS_DISPATCH_DATA_REMAINS) 1133 { 1134 DBusMessage *message; 1135 DBusList *link; 1136 1137 link = _dbus_message_loader_pop_message_link (transport->loader); 1138 _dbus_assert (link != NULL); 1139 1140 message = link->data; 1141 1142 _dbus_verbose ("queueing received message %p\n", message); 1143 1144 if (!_dbus_message_add_counter (message, transport->live_messages)) 1145 { 1146 _dbus_message_loader_putback_message_link (transport->loader, 1147 link); 1148 status = DBUS_DISPATCH_NEED_MEMORY; 1149 break; 1150 } 1151 else 1152 { 1153 /* pass ownership of link and message ref to connection */ 1154 _dbus_connection_queue_received_message_link (transport->connection, 1155 link); 1156 } 1157 } 1158 1159 if (_dbus_message_loader_get_is_corrupted (transport->loader)) 1160 { 1161 _dbus_verbose ("Corrupted message stream, disconnecting\n"); 1162 _dbus_transport_disconnect (transport); 1163 } 1164 1165 return status != DBUS_DISPATCH_NEED_MEMORY; 1166 } 1167 1168 /** 1169 * See dbus_connection_set_max_message_size(). 1170 * 1171 * @param transport the transport 1172 * @param size the max size of a single message 1173 */ 1174 void 1175 _dbus_transport_set_max_message_size (DBusTransport *transport, 1176 long size) 1177 { 1178 _dbus_message_loader_set_max_message_size (transport->loader, size); 1179 } 1180 1181 /** 1182 * See dbus_connection_set_max_message_unix_fds(). 1183 * 1184 * @param transport the transport 1185 * @param n the max number of unix fds of a single message 1186 */ 1187 void 1188 _dbus_transport_set_max_message_unix_fds (DBusTransport *transport, 1189 long n) 1190 { 1191 _dbus_message_loader_set_max_message_unix_fds (transport->loader, n); 1192 } 1193 1194 /** 1195 * See dbus_connection_get_max_message_size(). 1196 * 1197 * @param transport the transport 1198 * @returns max message size 1199 */ 1200 long 1201 _dbus_transport_get_max_message_size (DBusTransport *transport) 1202 { 1203 return _dbus_message_loader_get_max_message_size (transport->loader); 1204 } 1205 1206 /** 1207 * See dbus_connection_get_max_message_unix_fds(). 1208 * 1209 * @param transport the transport 1210 * @returns max message unix fds 1211 */ 1212 long 1213 _dbus_transport_get_max_message_unix_fds (DBusTransport *transport) 1214 { 1215 return _dbus_message_loader_get_max_message_unix_fds (transport->loader); 1216 } 1217 1218 /** 1219 * See dbus_connection_set_max_received_size(). 1220 * 1221 * @param transport the transport 1222 * @param size the max size of all incoming messages 1223 */ 1224 void 1225 _dbus_transport_set_max_received_size (DBusTransport *transport, 1226 long size) 1227 { 1228 transport->max_live_messages_size = size; 1229 _dbus_counter_set_notify (transport->live_messages, 1230 transport->max_live_messages_size, 1231 transport->max_live_messages_unix_fds, 1232 live_messages_notify, 1233 transport); 1234 } 1235 1236 /** 1237 * See dbus_connection_set_max_received_unix_fds(). 1238 * 1239 * @param transport the transport 1240 * @param n the max unix fds of all incoming messages 1241 */ 1242 void 1243 _dbus_transport_set_max_received_unix_fds (DBusTransport *transport, 1244 long n) 1245 { 1246 transport->max_live_messages_unix_fds = n; 1247 _dbus_counter_set_notify (transport->live_messages, 1248 transport->max_live_messages_size, 1249 transport->max_live_messages_unix_fds, 1250 live_messages_notify, 1251 transport); 1252 } 1253 1254 /** 1255 * See dbus_connection_get_max_received_size(). 1256 * 1257 * @param transport the transport 1258 * @returns max bytes for all live messages 1259 */ 1260 long 1261 _dbus_transport_get_max_received_size (DBusTransport *transport) 1262 { 1263 return transport->max_live_messages_size; 1264 } 1265 1266 /** 1267 * See dbus_connection_set_max_received_unix_fds(). 1268 * 1269 * @param transport the transport 1270 * @returns max unix fds for all live messages 1271 */ 1272 long 1273 _dbus_transport_get_max_received_unix_fds (DBusTransport *transport) 1274 { 1275 return transport->max_live_messages_unix_fds; 1276 } 1277 1278 /** 1279 * See dbus_connection_get_unix_user(). 1280 * 1281 * @param transport the transport 1282 * @param uid return location for the user ID 1283 * @returns #TRUE if uid is filled in with a valid user ID 1284 */ 1285 dbus_bool_t 1286 _dbus_transport_get_unix_user (DBusTransport *transport, 1287 unsigned long *uid) 1288 { 1289 DBusCredentials *auth_identity; 1290 1291 *uid = _DBUS_INT32_MAX; /* better than some root or system user in 1292 * case of bugs in the caller. Caller should 1293 * never use this value on purpose, however. 1294 */ 1295 1296 if (!transport->authenticated) 1297 return FALSE; 1298 1299 auth_identity = _dbus_auth_get_identity (transport->auth); 1300 1301 if (_dbus_credentials_include (auth_identity, 1302 DBUS_CREDENTIAL_UNIX_USER_ID)) 1303 { 1304 *uid = _dbus_credentials_get_unix_uid (auth_identity); 1305 return TRUE; 1306 } 1307 else 1308 return FALSE; 1309 } 1310 1311 /** 1312 * See dbus_connection_get_unix_process_id(). 1313 * 1314 * @param transport the transport 1315 * @param pid return location for the process ID 1316 * @returns #TRUE if uid is filled in with a valid process ID 1317 */ 1318 dbus_bool_t 1319 _dbus_transport_get_unix_process_id (DBusTransport *transport, 1320 unsigned long *pid) 1321 { 1322 DBusCredentials *auth_identity; 1323 1324 *pid = DBUS_PID_UNSET; /* Caller should never use this value on purpose, 1325 * but we set it to a safe number, INT_MAX, 1326 * just to root out possible bugs in bad callers. 1327 */ 1328 1329 if (!transport->authenticated) 1330 return FALSE; 1331 1332 auth_identity = _dbus_auth_get_identity (transport->auth); 1333 1334 if (_dbus_credentials_include (auth_identity, 1335 DBUS_CREDENTIAL_UNIX_PROCESS_ID)) 1336 { 1337 *pid = _dbus_credentials_get_unix_pid (auth_identity); 1338 return TRUE; 1339 } 1340 else 1341 return FALSE; 1342 } 1343 1344 /** 1345 * See dbus_connection_get_adt_audit_session_data(). 1346 * 1347 * @param transport the transport 1348 * @param data return location for the ADT audit data 1349 * @param data_size return length of audit data 1350 * @returns #TRUE if audit data is filled in with a valid ucred 1351 */ 1352 dbus_bool_t 1353 _dbus_transport_get_adt_audit_session_data (DBusTransport *transport, 1354 void **data, 1355 int *data_size) 1356 { 1357 DBusCredentials *auth_identity; 1358 1359 *data = NULL; 1360 *data_size = 0; 1361 1362 if (!transport->authenticated) 1363 return FALSE; 1364 1365 auth_identity = _dbus_auth_get_identity (transport->auth); 1366 1367 if (_dbus_credentials_include (auth_identity, 1368 DBUS_CREDENTIAL_ADT_AUDIT_DATA_ID)) 1369 { 1370 *data = (void *) _dbus_credentials_get_adt_audit_data (auth_identity); 1371 *data_size = _dbus_credentials_get_adt_audit_data_size (auth_identity); 1372 return TRUE; 1373 } 1374 else 1375 return FALSE; 1376 } 1377 1378 /** 1379 * See dbus_connection_set_unix_user_function(). 1380 * 1381 * @param transport the transport 1382 * @param function the predicate 1383 * @param data data to pass to the predicate 1384 * @param free_data_function function to free the data 1385 * @param old_data the old user data to be freed 1386 * @param old_free_data_function old free data function to free it with 1387 */ 1388 void 1389 _dbus_transport_set_unix_user_function (DBusTransport *transport, 1390 DBusAllowUnixUserFunction function, 1391 void *data, 1392 DBusFreeFunction free_data_function, 1393 void **old_data, 1394 DBusFreeFunction *old_free_data_function) 1395 { 1396 *old_data = transport->unix_user_data; 1397 *old_free_data_function = transport->free_unix_user_data; 1398 1399 transport->unix_user_function = function; 1400 transport->unix_user_data = data; 1401 transport->free_unix_user_data = free_data_function; 1402 } 1403 1404 /** 1405 * See dbus_connection_get_windows_user(). 1406 * 1407 * @param transport the transport 1408 * @param windows_sid_p return location for the user ID 1409 * @returns #TRUE if user is available; the returned value may still be #NULL if no memory to copy it 1410 */ 1411 dbus_bool_t 1412 _dbus_transport_get_windows_user (DBusTransport *transport, 1413 char **windows_sid_p) 1414 { 1415 DBusCredentials *auth_identity; 1416 1417 *windows_sid_p = NULL; 1418 1419 if (!transport->authenticated) 1420 return FALSE; 1421 1422 auth_identity = _dbus_auth_get_identity (transport->auth); 1423 1424 if (_dbus_credentials_include (auth_identity, 1425 DBUS_CREDENTIAL_WINDOWS_SID)) 1426 { 1427 /* If no memory, we are supposed to return TRUE and set NULL */ 1428 *windows_sid_p = _dbus_strdup (_dbus_credentials_get_windows_sid (auth_identity)); 1429 1430 return TRUE; 1431 } 1432 else 1433 return FALSE; 1434 } 1435 1436 /** 1437 * See dbus_connection_set_windows_user_function(). 1438 * 1439 * @param transport the transport 1440 * @param function the predicate 1441 * @param data data to pass to the predicate 1442 * @param free_data_function function to free the data 1443 * @param old_data the old user data to be freed 1444 * @param old_free_data_function old free data function to free it with 1445 */ 1446 1447 void 1448 _dbus_transport_set_windows_user_function (DBusTransport *transport, 1449 DBusAllowWindowsUserFunction function, 1450 void *data, 1451 DBusFreeFunction free_data_function, 1452 void **old_data, 1453 DBusFreeFunction *old_free_data_function) 1454 { 1455 *old_data = transport->windows_user_data; 1456 *old_free_data_function = transport->free_windows_user_data; 1457 1458 transport->windows_user_function = function; 1459 transport->windows_user_data = data; 1460 transport->free_windows_user_data = free_data_function; 1461 } 1462 1463 /** 1464 * Sets the SASL authentication mechanisms supported by this transport. 1465 * 1466 * @param transport the transport 1467 * @param mechanisms the #NULL-terminated array of mechanisms 1468 * 1469 * @returns #FALSE if no memory 1470 */ 1471 dbus_bool_t 1472 _dbus_transport_set_auth_mechanisms (DBusTransport *transport, 1473 const char **mechanisms) 1474 { 1475 return _dbus_auth_set_mechanisms (transport->auth, mechanisms); 1476 } 1477 1478 /** 1479 * See dbus_connection_set_allow_anonymous() 1480 * 1481 * @param transport the transport 1482 * @param value #TRUE to allow anonymous connection 1483 */ 1484 void 1485 _dbus_transport_set_allow_anonymous (DBusTransport *transport, 1486 dbus_bool_t value) 1487 { 1488 transport->allow_anonymous = value != FALSE; 1489 } 1490 1491 /** @} */ 1492
