source3/winbindd/winbindd_dual.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    Winbind child daemons
   5
   6    Copyright (C) Andrew Tridgell 2002
   7    Copyright (C) Volker Lendecke 2004,2005
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  21 */
  22
  23 /*
  24  * We fork a child per domain to be able to act non-blocking in the main
  25  * winbind daemon. A domain controller thousands of miles away being being
  26  * slow replying with a 10.000 user list should not hold up netlogon calls
  27  * that can be handled locally.
  28  */
  29
  30 #include "includes.h"
  31 #include "winbindd.h"
  32
  33 #undef DBGC_CLASS
  34 #define DBGC_CLASS DBGC_WINBIND
  35
  36 extern bool override_logfile;
  37
  38 /* Read some data from a client connection */
  39
  40 static void child_read_request(struct winbindd_cli_state *state)
  41 {
  42         ssize_t len;
  43
  44         /* Read data */
  45
  46         len = read_data(state->sock, (char *)&state->request,
  47                         sizeof(state->request), NULL);
  48
  49         if (len != sizeof(state->request)) {
  50                 DEBUG(len > 0 ? 0 : 3, ("Got invalid request length: %d\n", (int)len));
  51                 state->finished = True;
  52                 return;
  53         }
  54
  55         if (state->request.extra_len == 0) {
  56                 state->request.extra_data.data = NULL;
  57                 return;
  58         }
  59
  60         DEBUG(10, ("Need to read %d extra bytes\n", (int)state->request.extra_len));
  61
  62         state->request.extra_data.data =
  63                 SMB_MALLOC_ARRAY(char, state->request.extra_len + 1);
  64
  65         if (state->request.extra_data.data == NULL) {
  66                 DEBUG(0, ("malloc failed\n"));
  67                 state->finished = True;
  68                 return;
  69         }
  70
  71         /* Ensure null termination */
  72         state->request.extra_data.data[state->request.extra_len] = '\0';
  73
  74         len = read_data(state->sock, state->request.extra_data.data,
  75                         state->request.extra_len, NULL);
  76
  77         if (len != state->request.extra_len) {
  78                 DEBUG(0, ("Could not read extra data\n"));
  79                 state->finished = True;
  80                 return;
  81         }
  82 }
  83
  84 /*
  85  * Machinery for async requests sent to children. You set up a
  86  * winbindd_request, select a child to query, and issue a async_request
  87  * call. When the request is completed, the callback function you specified is
  88  * called back with the private pointer you gave to async_request.
  89  */
  90
  91 struct winbindd_async_request {
  92         struct winbindd_async_request *next, *prev;
  93         TALLOC_CTX *mem_ctx;
  94         struct winbindd_child *child;
  95         struct winbindd_request *request;
  96         struct winbindd_response *response;
  97         void (*continuation)(void *private_data, bool success);
  98         struct timed_event *reply_timeout_event;
  99         pid_t child_pid; /* pid of the child we're waiting on. Used to detect
 100                             a restart of the child (child->pid != child_pid). */
 101         void *private_data;
 102 };
 103
 104 static void async_main_request_sent(void *private_data, bool success);
 105 static void async_request_sent(void *private_data, bool success);
 106 static void async_reply_recv(void *private_data, bool success);
 107 static void schedule_async_request(struct winbindd_child *child);
 108
 109 void async_request(TALLOC_CTX *mem_ctx, struct winbindd_child *child,
 110                    struct winbindd_request *request,
 111                    struct winbindd_response *response,
 112                    void (*continuation)(void *private_data, bool success),
 113                    void *private_data)
 114 {
 115         struct winbindd_async_request *state;
 116
 117         SMB_ASSERT(continuation != NULL);
 118
 119         state = TALLOC_P(mem_ctx, struct winbindd_async_request);
 120
 121         if (state == NULL) {
 122                 DEBUG(0, ("talloc failed\n"));
 123                 continuation(private_data, False);
 124                 return;
 125         }
 126
 127         state->mem_ctx = mem_ctx;
 128         state->child = child;
 129         state->request = request;
 130         state->response = response;
 131         state->continuation = continuation;
 132         state->private_data = private_data;
 133
 134         DLIST_ADD_END(child->requests, state, struct winbindd_async_request *);
 135
 136         schedule_async_request(child);
 137
 138         return;
 139 }
 140
 141 static void async_main_request_sent(void *private_data, bool success)
 142 {
 143         struct winbindd_async_request *state =
 144                 talloc_get_type_abort(private_data, struct winbindd_async_request);
 145
 146         if (!success) {
 147                 DEBUG(5, ("Could not send async request\n"));
 148
 149                 state->response->length = sizeof(struct winbindd_response);
 150                 state->response->result = WINBINDD_ERROR;
 151                 state->continuation(state->private_data, False);
 152                 return;
 153         }
 154
 155         if (state->request->extra_len == 0) {
 156                 async_request_sent(private_data, True);
 157                 return;
 158         }
 159
 160         setup_async_write(&state->child->event, state->request->extra_data.data,
 161                           state->request->extra_len,
 162                           async_request_sent, state);
 163 }
 164
 165 /****************************************************************
 166  Handler triggered if the child winbindd doesn't respond within
 167  a given timeout.
 168 ****************************************************************/
 169
 170 static void async_request_timeout_handler(struct event_context *ctx,
 171                                         struct timed_event *te,
 172                                         const struct timeval *now,
 173                                         void *private_data)
 174 {
 175         struct winbindd_async_request *state =
 176                 talloc_get_type_abort(private_data, struct winbindd_async_request);
 177
 178         DEBUG(0,("async_request_timeout_handler: child pid %u is not responding. "
 179                 "Closing connection to it.\n",
 180                 state->child_pid ));
 181
 182         /* Deal with the reply - set to error. */
 183         async_reply_recv(private_data, False);
 184 }
 185
 186 /**************************************************************
 187  Common function called on both async send and recv fail.
 188  Cleans up the child and schedules the next request.
 189 **************************************************************/
 190
 191 static void async_request_fail(struct winbindd_async_request *state)
 192 {
 193         DLIST_REMOVE(state->child->requests, state);
 194
 195         TALLOC_FREE(state->reply_timeout_event);
 196
 197         SMB_ASSERT(state->child_pid != (pid_t)0);
 198
 199         /* If not already reaped, send kill signal to child. */
 200         if (state->child->pid == state->child_pid) {
 201                 kill(state->child_pid, SIGTERM);
 202
 203                 /*
 204                  * Close the socket to the child.
 205                  */
 206                 winbind_child_died(state->child_pid);
 207         }
 208
 209         state->response->length = sizeof(struct winbindd_response);
 210         state->response->result = WINBINDD_ERROR;
 211         state->continuation(state->private_data, False);
 212 }
 213
 214 static void async_request_sent(void *private_data_data, bool success)
 215 {
 216         struct winbindd_async_request *state =
 217                 talloc_get_type_abort(private_data_data, struct winbindd_async_request);
 218
 219         if (!success) {
 220                 DEBUG(5, ("Could not send async request to child pid %u\n",
 221                         (unsigned int)state->child_pid ));
 222                 async_request_fail(state);
 223                 return;
 224         }
 225
 226         /* Request successfully sent to the child, setup the wait for reply */
 227
 228         setup_async_read(&state->child->event,
 229                          &state->response->result,
 230                          sizeof(state->response->result),
 231                          async_reply_recv, state);
 232
 233         /*
 234          * Set up a timeout of 300 seconds for the response.
 235          * If we don't get it close the child socket and
 236          * report failure.
 237          */
 238
 239         state->reply_timeout_event = event_add_timed(winbind_event_context(),
 240                                                         NULL,
 241                                                         timeval_current_ofs(300,0),
 242                                                         "async_request_timeout",
 243                                                         async_request_timeout_handler,
 244                                                         state);
 245         if (!state->reply_timeout_event) {
 246                 smb_panic("async_request_sent: failed to add timeout handler.\n");
 247         }
 248 }
 249
 250 static void async_reply_recv(void *private_data, bool success)
 251 {
 252         struct winbindd_async_request *state =
 253                 talloc_get_type_abort(private_data, struct winbindd_async_request);
 254         struct winbindd_child *child = state->child;
 255
 256         TALLOC_FREE(state->reply_timeout_event);
 257
 258         state->response->length = sizeof(struct winbindd_response);
 259
 260         if (!success) {
 261                 DEBUG(5, ("Could not receive async reply from child pid %u\n",
 262                         (unsigned int)state->child_pid ));
 263
 264                 cache_cleanup_response(state->child_pid);
 265                 async_request_fail(state);
 266                 return;
 267         }
 268
 269         SMB_ASSERT(cache_retrieve_response(state->child_pid,
 270                                            state->response));
 271
 272         cache_cleanup_response(state->child_pid);
 273
 274         DLIST_REMOVE(child->requests, state);
 275
 276         schedule_async_request(child);
 277
 278         state->continuation(state->private_data, True);
 279 }
 280
 281 static bool fork_domain_child(struct winbindd_child *child);
 282
 283 static void schedule_async_request(struct winbindd_child *child)
 284 {
 285         struct winbindd_async_request *request = child->requests;
 286
 287         if (request == NULL) {
 288                 return;
 289         }
 290
 291         if (child->event.flags != 0) {
 292                 return;         /* Busy */
 293         }
 294
 295         if ((child->pid == 0) && (!fork_domain_child(child))) {
 296                 /* Cancel all outstanding requests */
 297
 298                 while (request != NULL) {
 299                         /* request might be free'd in the continuation */
 300                         struct winbindd_async_request *next = request->next;
 301                         request->continuation(request->private_data, False);
 302                         request = next;
 303                 }
 304                 return;
 305         }
 306
 307         /* Now we know who we're sending to - remember the pid. */
 308         request->child_pid = child->pid;
 309
 310         setup_async_write(&child->event, request->request,
 311                           sizeof(*request->request),
 312                           async_main_request_sent, request);
 313
 314         return;
 315 }
 316
 317 struct domain_request_state {
 318         TALLOC_CTX *mem_ctx;
 319         struct winbindd_domain *domain;
 320         struct winbindd_request *request;
 321         struct winbindd_response *response;
 322         void (*continuation)(void *private_data_data, bool success);
 323         void *private_data_data;
 324 };
 325
 326 static void domain_init_recv(void *private_data_data, bool success);
 327
 328 void async_domain_request(TALLOC_CTX *mem_ctx,
 329                           struct winbindd_domain *domain,
 330                           struct winbindd_request *request,
 331                           struct winbindd_response *response,
 332                           void (*continuation)(void *private_data_data, bool success),
 333                           void *private_data_data)
 334 {
 335         struct domain_request_state *state;
 336
 337         if (domain->initialized) {
 338                 async_request(mem_ctx, &domain->child, request, response,
 339                               continuation, private_data_data);
 340                 return;
 341         }
 342
 343         state = TALLOC_P(mem_ctx, struct domain_request_state);
 344         if (state == NULL) {
 345                 DEBUG(0, ("talloc failed\n"));
 346                 continuation(private_data_data, False);
 347                 return;
 348         }
 349
 350         state->mem_ctx = mem_ctx;
 351         state->domain = domain;
 352         state->request = request;
 353         state->response = response;
 354         state->continuation = continuation;
 355         state->private_data_data = private_data_data;
 356
 357         init_child_connection(domain, domain_init_recv, state);
 358 }
 359
 360 static void domain_init_recv(void *private_data_data, bool success)
 361 {
 362         struct domain_request_state *state =
 363                 talloc_get_type_abort(private_data_data, struct domain_request_state);
 364
 365         if (!success) {
 366                 DEBUG(5, ("Domain init returned an error\n"));
 367                 state->continuation(state->private_data_data, False);
 368                 return;
 369         }
 370
 371         async_request(state->mem_ctx, &state->domain->child,
 372                       state->request, state->response,
 373                       state->continuation, state->private_data_data);
 374 }
 375
 376 static void recvfrom_child(void *private_data_data, bool success)
 377 {
 378         struct winbindd_cli_state *state =
 379                 talloc_get_type_abort(private_data_data, struct winbindd_cli_state);
 380         enum winbindd_result result = state->response.result;
 381
 382         /* This is an optimization: The child has written directly to the
 383          * response buffer. The request itself is still in pending state,
 384          * state that in the result code. */
 385
 386         state->response.result = WINBINDD_PENDING;
 387
 388         if ((!success) || (result != WINBINDD_OK)) {
 389                 request_error(state);
 390                 return;
 391         }
 392
 393         request_ok(state);
 394 }
 395
 396 void sendto_child(struct winbindd_cli_state *state,
 397                   struct winbindd_child *child)
 398 {
 399         async_request(state->mem_ctx, child, &state->request,
 400                       &state->response, recvfrom_child, state);
 401 }
 402
 403 void sendto_domain(struct winbindd_cli_state *state,
 404                    struct winbindd_domain *domain)
 405 {
 406         async_domain_request(state->mem_ctx, domain,
 407                              &state->request, &state->response,
 408                              recvfrom_child, state);
 409 }
 410
 411 static void child_process_request(struct winbindd_child *child,
 412                                   struct winbindd_cli_state *state)
 413 {
 414         struct winbindd_domain *domain = child->domain;
 415         const struct winbindd_child_dispatch_table *table = child->table;
 416
 417         /* Free response data - we may be interrupted and receive another
 418            command before being able to send this data off. */
 419
 420         state->response.result = WINBINDD_ERROR;
 421         state->response.length = sizeof(struct winbindd_response);
 422
 423         /* as all requests in the child are sync, we can use talloc_tos() */
 424         state->mem_ctx = talloc_tos();
 425
 426         /* Process command */
 427
 428         for (; table->name; table++) {
 429                 if (state->request.cmd == table->struct_cmd) {
 430                         DEBUG(10,("child_process_request: request fn %s\n",
 431                                   table->name));
 432                         state->response.result = table->struct_fn(domain, state);
 433                         return;
 434                 }
 435         }
 436
 437         DEBUG(1 ,("child_process_request: unknown request fn number %d\n",
 438                   (int)state->request.cmd));
 439         state->response.result = WINBINDD_ERROR;
 440 }
 441
 442 void setup_child(struct winbindd_child *child,
 443                  const struct winbindd_child_dispatch_table *table,
 444                  const char *logprefix,
 445                  const char *logname)
 446 {
 447         if (logprefix && logname) {
 448                 if (asprintf(&child->logfilename, "%s/%s-%s",
 449                              get_dyn_LOGFILEBASE(), logprefix, logname) < 0) {
 450                         smb_panic("Internal error: asprintf failed");
 451                 }
 452         } else {
 453                 smb_panic("Internal error: logprefix == NULL && "
 454                           "logname == NULL");
 455         }
 456
 457         child->domain = NULL;
 458         child->table = table;
 459 }
 460
 461 struct winbindd_child *children = NULL;
 462
 463 void winbind_child_died(pid_t pid)
 464 {
 465         struct winbindd_child *child;
 466
 467         for (child = children; child != NULL; child = child->next) {
 468                 if (child->pid == pid) {
 469                         break;
 470                 }
 471         }
 472
 473         if (child == NULL) {
 474                 DEBUG(5, ("Already reaped child %u died\n", (unsigned int)pid));
 475                 return;
 476         }
 477
 478         remove_fd_event(&child->event);
 479         close(child->event.fd);
 480         child->event.fd = 0;
 481         child->event.flags = 0;
 482         child->pid = 0;
 483
 484         schedule_async_request(child);
 485 }
 486
 487 /* Ensure any negative cache entries with the netbios or realm names are removed. */
 488
 489 void winbindd_flush_negative_conn_cache(struct winbindd_domain *domain)
 490 {
 491         flush_negative_conn_cache_for_domain(domain->name);
 492         if (*domain->alt_name) {
 493                 flush_negative_conn_cache_for_domain(domain->alt_name);
 494         }
 495 }
 496
 497 /* Set our domains as offline and forward the offline message to our children. */
 498
 499 void winbind_msg_offline(struct messaging_context *msg_ctx,
 500                          void *private_data,
 501                          uint32_t msg_type,
 502                          struct server_id server_id,
 503                          DATA_BLOB *data)
 504 {
 505         struct winbindd_child *child;
 506         struct winbindd_domain *domain;
 507
 508         DEBUG(10,("winbind_msg_offline: got offline message.\n"));
 509
 510         if (!lp_winbind_offline_logon()) {
 511                 DEBUG(10,("winbind_msg_offline: rejecting offline message.\n"));
 512                 return;
 513         }
 514
 515         /* Set our global state as offline. */
 516         if (!set_global_winbindd_state_offline()) {
 517                 DEBUG(10,("winbind_msg_offline: offline request failed.\n"));
 518                 return;
 519         }
 520
 521         /* Set all our domains as offline. */
 522         for (domain = domain_list(); domain; domain = domain->next) {
 523                 if (domain->internal) {
 524                         continue;
 525                 }
 526                 DEBUG(5,("winbind_msg_offline: marking %s offline.\n", domain->name));
 527                 set_domain_offline(domain);
 528         }
 529
 530         for (child = children; child != NULL; child = child->next) {
 531                 /* Don't send message to internal childs.  We've already
 532                    done so above. */
 533                 if (!child->domain || winbindd_internal_child(child)) {
 534                         continue;
 535                 }
 536
 537                 /* Or internal domains (this should not be possible....) */
 538                 if (child->domain->internal) {
 539                         continue;
 540                 }
 541
 542                 /* Each winbindd child should only process requests for one domain - make sure
 543                    we only set it online / offline for that domain. */
 544
 545                 DEBUG(10,("winbind_msg_offline: sending message to pid %u for domain %s.\n",
 546                         (unsigned int)child->pid, domain->name ));
 547
 548                 messaging_send_buf(msg_ctx, pid_to_procid(child->pid),
 549                                    MSG_WINBIND_OFFLINE,
 550                                    (uint8 *)child->domain->name,
 551                                    strlen(child->domain->name)+1);
 552         }
 553 }
 554
 555 /* Set our domains as online and forward the online message to our children. */
 556
 557 void winbind_msg_online(struct messaging_context *msg_ctx,
 558                         void *private_data,
 559                         uint32_t msg_type,
 560                         struct server_id server_id,
 561                         DATA_BLOB *data)
 562 {
 563         struct winbindd_child *child;
 564         struct winbindd_domain *domain;
 565
 566         DEBUG(10,("winbind_msg_online: got online message.\n"));
 567
 568         if (!lp_winbind_offline_logon()) {
 569                 DEBUG(10,("winbind_msg_online: rejecting online message.\n"));
 570                 return;
 571         }
 572
 573         /* Set our global state as online. */
 574         set_global_winbindd_state_online();
 575
 576         smb_nscd_flush_user_cache();
 577         smb_nscd_flush_group_cache();
 578
 579         /* Set all our domains as online. */
 580         for (domain = domain_list(); domain; domain = domain->next) {
 581                 if (domain->internal) {
 582                         continue;
 583                 }
 584                 DEBUG(5,("winbind_msg_online: requesting %s to go online.\n", domain->name));
 585
 586                 winbindd_flush_negative_conn_cache(domain);
 587                 set_domain_online_request(domain);
 588
 589                 /* Send an online message to the idmap child when our
 590                    primary domain comes back online */
 591
 592                 if ( domain->primary ) {
 593                         struct winbindd_child *idmap = idmap_child();
 594
 595                         if ( idmap->pid != 0 ) {
 596                                 messaging_send_buf(msg_ctx,
 597                                                    pid_to_procid(idmap->pid),
 598                                                    MSG_WINBIND_ONLINE,
 599                                                    (uint8 *)domain->name,
 600                                                    strlen(domain->name)+1);
 601                         }
 602
 603                 }
 604         }
 605
 606         for (child = children; child != NULL; child = child->next) {
 607                 /* Don't send message to internal childs. */
 608                 if (!child->domain || winbindd_internal_child(child)) {
 609                         continue;
 610                 }
 611
 612                 /* Or internal domains (this should not be possible....) */
 613                 if (child->domain->internal) {
 614                         continue;
 615                 }
 616
 617                 /* Each winbindd child should only process requests for one domain - make sure
 618                    we only set it online / offline for that domain. */
 619
 620                 DEBUG(10,("winbind_msg_online: sending message to pid %u for domain %s.\n",
 621                         (unsigned int)child->pid, child->domain->name ));
 622
 623                 messaging_send_buf(msg_ctx, pid_to_procid(child->pid),
 624                                    MSG_WINBIND_ONLINE,
 625                                    (uint8 *)child->domain->name,
 626                                    strlen(child->domain->name)+1);
 627         }
 628 }
 629
 630 /* Forward the online/offline messages to our children. */
 631 void winbind_msg_onlinestatus(struct messaging_context *msg_ctx,
 632                               void *private_data,
 633                               uint32_t msg_type,
 634                               struct server_id server_id,
 635                               DATA_BLOB *data)
 636 {
 637         struct winbindd_child *child;
 638
 639         DEBUG(10,("winbind_msg_onlinestatus: got onlinestatus message.\n"));
 640
 641         for (child = children; child != NULL; child = child->next) {
 642                 if (child->domain && child->domain->primary) {
 643                         DEBUG(10,("winbind_msg_onlinestatus: "
 644                                   "sending message to pid %u of primary domain.\n",
 645                                   (unsigned int)child->pid));
 646                         messaging_send_buf(msg_ctx, pid_to_procid(child->pid),
 647                                            MSG_WINBIND_ONLINESTATUS,
 648                                            (uint8 *)data->data,
 649                                            data->length);
 650                         break;
 651                 }
 652         }
 653 }
 654
 655 void winbind_msg_dump_event_list(struct messaging_context *msg_ctx,
 656                                  void *private_data,
 657                                  uint32_t msg_type,
 658                                  struct server_id server_id,
 659                                  DATA_BLOB *data)
 660 {
 661         struct winbindd_child *child;
 662
 663         DEBUG(10,("winbind_msg_dump_event_list received\n"));
 664
 665         dump_event_list(winbind_event_context());
 666
 667         for (child = children; child != NULL; child = child->next) {
 668
 669                 DEBUG(10,("winbind_msg_dump_event_list: sending message to pid %u\n",
 670                         (unsigned int)child->pid));
 671
 672                 messaging_send_buf(msg_ctx, pid_to_procid(child->pid),
 673                                    MSG_DUMP_EVENT_LIST,
 674                                    NULL, 0);
 675         }
 676
 677 }
 678
 679 static void account_lockout_policy_handler(struct event_context *ctx,
 680                                            struct timed_event *te,
 681                                            const struct timeval *now,
 682                                            void *private_data)
 683 {
 684         struct winbindd_child *child =
 685                 (struct winbindd_child *)private_data;
 686         TALLOC_CTX *mem_ctx = NULL;
 687         struct winbindd_methods *methods;
 688         SAM_UNK_INFO_12 lockout_policy;
 689         NTSTATUS result;
 690
 691         DEBUG(10,("account_lockout_policy_handler called\n"));
 692
 693         TALLOC_FREE(child->lockout_policy_event);
 694
 695         if ( !winbindd_can_contact_domain( child->domain ) ) {
 696                 DEBUG(10,("account_lockout_policy_handler: Removing myself since I "
 697                           "do not have an incoming trust to domain %s\n",
 698                           child->domain->name));
 699
 700                 return;
 701         }
 702
 703         methods = child->domain->methods;
 704
 705         mem_ctx = talloc_init("account_lockout_policy_handler ctx");
 706         if (!mem_ctx) {
 707                 result = NT_STATUS_NO_MEMORY;
 708         } else {
 709                 result = methods->lockout_policy(child->domain, mem_ctx, &lockout_policy);
 710         }
 711         TALLOC_FREE(mem_ctx);
 712
 713         if (!NT_STATUS_IS_OK(result)) {
 714                 DEBUG(10,("account_lockout_policy_handler: lockout_policy failed error %s\n",
 715                          nt_errstr(result)));
 716         }
 717
 718         child->lockout_policy_event = event_add_timed(winbind_event_context(), NULL,
 719                                                       timeval_current_ofs(3600, 0),
 720                                                       "account_lockout_policy_handler",
 721                                                       account_lockout_policy_handler,
 722                                                       child);
 723 }
 724
 725 /* Deal with a request to go offline. */
 726
 727 static void child_msg_offline(struct messaging_context *msg,
 728                               void *private_data,
 729                               uint32_t msg_type,
 730                               struct server_id server_id,
 731                               DATA_BLOB *data)
 732 {
 733         struct winbindd_domain *domain;
 734         const char *domainname = (const char *)data->data;
 735
 736         if (data->data == NULL || data->length == 0) {
 737                 return;
 738         }
 739
 740         DEBUG(5,("child_msg_offline received for domain %s.\n", domainname));
 741
 742         if (!lp_winbind_offline_logon()) {
 743                 DEBUG(10,("child_msg_offline: rejecting offline message.\n"));
 744                 return;
 745         }
 746
 747         /* Mark the requested domain offline. */
 748
 749         for (domain = domain_list(); domain; domain = domain->next) {
 750                 if (domain->internal) {
 751                         continue;
 752                 }
 753                 if (strequal(domain->name, domainname)) {
 754                         DEBUG(5,("child_msg_offline: marking %s offline.\n", domain->name));
 755                         set_domain_offline(domain);
 756                 }
 757         }
 758 }
 759
 760 /* Deal with a request to go online. */
 761
 762 static void child_msg_online(struct messaging_context *msg,
 763                              void *private_data,
 764                              uint32_t msg_type,
 765                              struct server_id server_id,
 766                              DATA_BLOB *data)
 767 {
 768         struct winbindd_domain *domain;
 769         const char *domainname = (const char *)data->data;
 770
 771         if (data->data == NULL || data->length == 0) {
 772                 return;
 773         }
 774
 775         DEBUG(5,("child_msg_online received for domain %s.\n", domainname));
 776
 777         if (!lp_winbind_offline_logon()) {
 778                 DEBUG(10,("child_msg_online: rejecting online message.\n"));
 779                 return;
 780         }
 781
 782         /* Set our global state as online. */
 783         set_global_winbindd_state_online();
 784
 785         /* Try and mark everything online - delete any negative cache entries
 786            to force a reconnect now. */
 787
 788         for (domain = domain_list(); domain; domain = domain->next) {
 789                 if (domain->internal) {
 790                         continue;
 791                 }
 792                 if (strequal(domain->name, domainname)) {
 793                         DEBUG(5,("child_msg_online: requesting %s to go online.\n", domain->name));
 794                         winbindd_flush_negative_conn_cache(domain);
 795                         set_domain_online_request(domain);
 796                 }
 797         }
 798 }
 799
 800 static const char *collect_onlinestatus(TALLOC_CTX *mem_ctx)
 801 {
 802         struct winbindd_domain *domain;
 803         char *buf = NULL;
 804
 805         if ((buf = talloc_asprintf(mem_ctx, "global:%s ",
 806                                    get_global_winbindd_state_offline() ?
 807                                    "Offline":"Online")) == NULL) {
 808                 return NULL;
 809         }
 810
 811         for (domain = domain_list(); domain; domain = domain->next) {
 812                 if ((buf = talloc_asprintf_append_buffer(buf, "%s:%s ",
 813                                                   domain->name,
 814                                                   domain->online ?
 815                                                   "Online":"Offline")) == NULL) {
 816                         return NULL;
 817                 }
 818         }
 819
 820         buf = talloc_asprintf_append_buffer(buf, "\n");
 821
 822         DEBUG(5,("collect_onlinestatus: %s", buf));
 823
 824         return buf;
 825 }
 826
 827 static void child_msg_onlinestatus(struct messaging_context *msg_ctx,
 828                                    void *private_data,
 829                                    uint32_t msg_type,
 830                                    struct server_id server_id,
 831                                    DATA_BLOB *data)
 832 {
 833         TALLOC_CTX *mem_ctx;
 834         const char *message;
 835         struct server_id *sender;
 836
 837         DEBUG(5,("winbind_msg_onlinestatus received.\n"));
 838
 839         if (!data->data) {
 840                 return;
 841         }
 842
 843         sender = (struct server_id *)data->data;
 844
 845         mem_ctx = talloc_init("winbind_msg_onlinestatus");
 846         if (mem_ctx == NULL) {
 847                 return;
 848         }
 849
 850         message = collect_onlinestatus(mem_ctx);
 851         if (message == NULL) {
 852                 talloc_destroy(mem_ctx);
 853                 return;
 854         }
 855
 856         messaging_send_buf(msg_ctx, *sender, MSG_WINBIND_ONLINESTATUS,
 857                            (uint8 *)message, strlen(message) + 1);
 858
 859         talloc_destroy(mem_ctx);
 860 }
 861
 862 static void child_msg_dump_event_list(struct messaging_context *msg,
 863                                       void *private_data,
 864                                       uint32_t msg_type,
 865                                       struct server_id server_id,
 866                                       DATA_BLOB *data)
 867 {
 868         DEBUG(5,("child_msg_dump_event_list received\n"));
 869
 870         dump_event_list(winbind_event_context());
 871 }
 872
 873
 874 static bool fork_domain_child(struct winbindd_child *child)
 875 {
 876         int fdpair[2];
 877         struct winbindd_cli_state state;
 878         struct winbindd_domain *domain;
 879
 880         if (socketpair(AF_UNIX, SOCK_STREAM, 0, fdpair) != 0) {
 881                 DEBUG(0, ("Could not open child pipe: %s\n",
 882                           strerror(errno)));
 883                 return False;
 884         }
 885
 886         ZERO_STRUCT(state);
 887         state.pid = sys_getpid();
 888
 889         /* Stop zombies */
 890         CatchChild();
 891
 892         child->pid = sys_fork();
 893
 894         if (child->pid == -1) {
 895                 DEBUG(0, ("Could not fork: %s\n", strerror(errno)));
 896                 return False;
 897         }
 898
 899         if (child->pid != 0) {
 900                 /* Parent */
 901                 close(fdpair[0]);
 902                 child->next = child->prev = NULL;
 903                 DLIST_ADD(children, child);
 904                 child->event.fd = fdpair[1];
 905                 child->event.flags = 0;
 906                 child->requests = NULL;
 907                 add_fd_event(&child->event);
 908                 return True;
 909         }
 910
 911         /* Child */
 912
 913         state.sock = fdpair[0];
 914         close(fdpair[1]);
 915
 916         /* tdb needs special fork handling */
 917         if (tdb_reopen_all(1) == -1) {
 918                 DEBUG(0,("tdb_reopen_all failed.\n"));
 919                 _exit(0);
 920         }
 921
 922         close_conns_after_fork();
 923
 924         if (!override_logfile) {
 925                 lp_set_logfile(child->logfilename);
 926                 reopen_logs();
 927         }
 928
 929         /*
 930          * For clustering, we need to re-init our ctdbd connection after the
 931          * fork
 932          */
 933         if (!NT_STATUS_IS_OK(messaging_reinit(winbind_messaging_context())))
 934                 exit(1);
 935
 936         /* Don't handle the same messages as our parent. */
 937         messaging_deregister(winbind_messaging_context(),
 938                              MSG_SMB_CONF_UPDATED, NULL);
 939         messaging_deregister(winbind_messaging_context(),
 940                              MSG_SHUTDOWN, NULL);
 941         messaging_deregister(winbind_messaging_context(),
 942                              MSG_WINBIND_OFFLINE, NULL);
 943         messaging_deregister(winbind_messaging_context(),
 944                              MSG_WINBIND_ONLINE, NULL);
 945         messaging_deregister(winbind_messaging_context(),
 946                              MSG_WINBIND_ONLINESTATUS, NULL);
 947         messaging_deregister(winbind_messaging_context(),
 948                              MSG_DUMP_EVENT_LIST, NULL);
 949
 950         /* Handle online/offline messages. */
 951         messaging_register(winbind_messaging_context(), NULL,
 952                            MSG_WINBIND_OFFLINE, child_msg_offline);
 953         messaging_register(winbind_messaging_context(), NULL,
 954                            MSG_WINBIND_ONLINE, child_msg_online);
 955         messaging_register(winbind_messaging_context(), NULL,
 956                            MSG_WINBIND_ONLINESTATUS, child_msg_onlinestatus);
 957         messaging_register(winbind_messaging_context(), NULL,
 958                            MSG_DUMP_EVENT_LIST, child_msg_dump_event_list);
 959
 960         if ( child->domain ) {
 961                 child->domain->startup = True;
 962                 child->domain->startup_time = time(NULL);
 963         }
 964
 965         /* Ensure we have no pending check_online events other
 966            than one for this domain. */
 967
 968         for (domain = domain_list(); domain; domain = domain->next) {
 969                 if (domain != child->domain) {
 970                         TALLOC_FREE(domain->check_online_event);
 971                 }
 972         }
 973
 974         /* Ensure we're not handling an event inherited from
 975            our parent. */
 976
 977         cancel_named_event(winbind_event_context(),
 978                            "krb5_ticket_refresh_handler");
 979
 980         /* We might be in the idmap child...*/
 981         if (child->domain && !(child->domain->internal) &&
 982             lp_winbind_offline_logon()) {
 983
 984                 set_domain_online_request(child->domain);
 985
 986                 child->lockout_policy_event = event_add_timed(
 987                         winbind_event_context(), NULL, timeval_zero(),
 988                         "account_lockout_policy_handler",
 989                         account_lockout_policy_handler,
 990                         child);
 991         }
 992
 993         while (1) {
 994
 995                 int ret;
 996                 fd_set read_fds;
 997                 struct timeval t;
 998                 struct timeval *tp;
 999                 struct timeval now;
1000                 TALLOC_CTX *frame = talloc_stackframe();
1001
1002                 run_events(winbind_event_context(), 0, NULL, NULL);
1003
1004                 GetTimeOfDay(&now);
1005
1006                 if (child->domain && child->domain->startup &&
1007                                 (now.tv_sec > child->domain->startup_time + 30)) {
1008                         /* No longer in "startup" mode. */
1009                         DEBUG(10,("fork_domain_child: domain %s no longer in 'startup' mode.\n",
1010                                 child->domain->name ));
1011                         child->domain->startup = False;
1012                 }
1013
1014                 tp = get_timed_events_timeout(winbind_event_context(), &t);
1015                 if (tp) {
1016                         DEBUG(11,("select will use timeout of %u.%u seconds\n",
1017                                 (unsigned int)tp->tv_sec, (unsigned int)tp->tv_usec ));
1018                 }
1019
1020                 /* Handle messages */
1021
1022                 message_dispatch(winbind_messaging_context());
1023
1024                 FD_ZERO(&read_fds);
1025                 FD_SET(state.sock, &read_fds);
1026
1027                 ret = sys_select(state.sock + 1, &read_fds, NULL, NULL, tp);
1028
1029                 if (ret == 0) {
1030                         DEBUG(11,("nothing is ready yet, continue\n"));
1031                         TALLOC_FREE(frame);
1032                         continue;
1033                 }
1034
1035                 if (ret == -1 && errno == EINTR) {
1036                         /* We got a signal - continue. */
1037                         TALLOC_FREE(frame);
1038                         continue;
1039                 }
1040
1041                 if (ret == -1 && errno != EINTR) {
1042                         DEBUG(0,("select error occured\n"));
1043                         TALLOC_FREE(frame);
1044                         perror("select");
1045                         return False;
1046                 }
1047
1048                 /* fetch a request from the main daemon */
1049                 child_read_request(&state);
1050
1051                 if (state.finished) {
1052                         /* we lost contact with our parent */
1053                         exit(0);
1054                 }
1055
1056                 DEBUG(4,("child daemon request %d\n", (int)state.request.cmd));
1057
1058                 ZERO_STRUCT(state.response);
1059                 state.request.null_term = '\0';
1060                 child_process_request(child, &state);
1061
1062                 SAFE_FREE(state.request.extra_data.data);
1063
1064                 cache_store_response(sys_getpid(), &state.response);
1065
1066                 SAFE_FREE(state.response.extra_data.data);
1067
1068                 /* We just send the result code back, the result
1069                  * structure needs to be fetched via the
1070                  * winbindd_cache. Hmm. That needs fixing... */
1071
1072                 if (write_data(state.sock,
1073                                (const char *)&state.response.result,
1074                                sizeof(state.response.result)) !=
1075                     sizeof(state.response.result)) {
1076                         DEBUG(0, ("Could not write result\n"));
1077                         exit(1);
1078                 }
1079                 TALLOC_FREE(frame);
1080         }
1081 }