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         SAFE_FREE(child->logfilename);
 484
 485         schedule_async_request(child);
 486 }
 487
 488 /* Ensure any negative cache entries with the netbios or realm names are removed. */
 489
 490 void winbindd_flush_negative_conn_cache(struct winbindd_domain *domain)
 491 {
 492         flush_negative_conn_cache_for_domain(domain->name);
 493         if (*domain->alt_name) {
 494                 flush_negative_conn_cache_for_domain(domain->alt_name);
 495         }
 496 }
 497
 498 /* Set our domains as offline and forward the offline message to our children. */
 499
 500 void winbind_msg_offline(struct messaging_context *msg_ctx,
 501                          void *private_data,
 502                          uint32_t msg_type,
 503                          struct server_id server_id,
 504                          DATA_BLOB *data)
 505 {
 506         struct winbindd_child *child;
 507         struct winbindd_domain *domain;
 508
 509         DEBUG(10,("winbind_msg_offline: got offline message.\n"));
 510
 511         if (!lp_winbind_offline_logon()) {
 512                 DEBUG(10,("winbind_msg_offline: rejecting offline message.\n"));
 513                 return;
 514         }
 515
 516         /* Set our global state as offline. */
 517         if (!set_global_winbindd_state_offline()) {
 518                 DEBUG(10,("winbind_msg_offline: offline request failed.\n"));
 519                 return;
 520         }
 521
 522         /* Set all our domains as offline. */
 523         for (domain = domain_list(); domain; domain = domain->next) {
 524                 if (domain->internal) {
 525                         continue;
 526                 }
 527                 DEBUG(5,("winbind_msg_offline: marking %s offline.\n", domain->name));
 528                 set_domain_offline(domain);
 529         }
 530
 531         for (child = children; child != NULL; child = child->next) {
 532                 /* Don't send message to internal childs.  We've already
 533                    done so above. */
 534                 if (!child->domain || winbindd_internal_child(child)) {
 535                         continue;
 536                 }
 537
 538                 /* Or internal domains (this should not be possible....) */
 539                 if (child->domain->internal) {
 540                         continue;
 541                 }
 542
 543                 /* Each winbindd child should only process requests for one domain - make sure
 544                    we only set it online / offline for that domain. */
 545
 546                 DEBUG(10,("winbind_msg_offline: sending message to pid %u for domain %s.\n",
 547                         (unsigned int)child->pid, domain->name ));
 548
 549                 messaging_send_buf(msg_ctx, pid_to_procid(child->pid),
 550                                    MSG_WINBIND_OFFLINE,
 551                                    (uint8 *)child->domain->name,
 552                                    strlen(child->domain->name)+1);
 553         }
 554 }
 555
 556 /* Set our domains as online and forward the online message to our children. */
 557
 558 void winbind_msg_online(struct messaging_context *msg_ctx,
 559                         void *private_data,
 560                         uint32_t msg_type,
 561                         struct server_id server_id,
 562                         DATA_BLOB *data)
 563 {
 564         struct winbindd_child *child;
 565         struct winbindd_domain *domain;
 566
 567         DEBUG(10,("winbind_msg_online: got online message.\n"));
 568
 569         if (!lp_winbind_offline_logon()) {
 570                 DEBUG(10,("winbind_msg_online: rejecting online message.\n"));
 571                 return;
 572         }
 573
 574         /* Set our global state as online. */
 575         set_global_winbindd_state_online();
 576
 577         smb_nscd_flush_user_cache();
 578         smb_nscd_flush_group_cache();
 579
 580         /* Set all our domains as online. */
 581         for (domain = domain_list(); domain; domain = domain->next) {
 582                 if (domain->internal) {
 583                         continue;
 584                 }
 585                 DEBUG(5,("winbind_msg_online: requesting %s to go online.\n", domain->name));
 586
 587                 winbindd_flush_negative_conn_cache(domain);
 588                 set_domain_online_request(domain);
 589
 590                 /* Send an online message to the idmap child when our
 591                    primary domain comes back online */
 592
 593                 if ( domain->primary ) {
 594                         struct winbindd_child *idmap = idmap_child();
 595
 596                         if ( idmap->pid != 0 ) {
 597                                 messaging_send_buf(msg_ctx,
 598                                                    pid_to_procid(idmap->pid),
 599                                                    MSG_WINBIND_ONLINE,
 600                                                    (uint8 *)domain->name,
 601                                                    strlen(domain->name)+1);
 602                         }
 603
 604                 }
 605         }
 606
 607         for (child = children; child != NULL; child = child->next) {
 608                 /* Don't send message to internal childs. */
 609                 if (!child->domain || winbindd_internal_child(child)) {
 610                         continue;
 611                 }
 612
 613                 /* Or internal domains (this should not be possible....) */
 614                 if (child->domain->internal) {
 615                         continue;
 616                 }
 617
 618                 /* Each winbindd child should only process requests for one domain - make sure
 619                    we only set it online / offline for that domain. */
 620
 621                 DEBUG(10,("winbind_msg_online: sending message to pid %u for domain %s.\n",
 622                         (unsigned int)child->pid, child->domain->name ));
 623
 624                 messaging_send_buf(msg_ctx, pid_to_procid(child->pid),
 625                                    MSG_WINBIND_ONLINE,
 626                                    (uint8 *)child->domain->name,
 627                                    strlen(child->domain->name)+1);
 628         }
 629 }
 630
 631 /* Forward the online/offline messages to our children. */
 632 void winbind_msg_onlinestatus(struct messaging_context *msg_ctx,
 633                               void *private_data,
 634                               uint32_t msg_type,
 635                               struct server_id server_id,
 636                               DATA_BLOB *data)
 637 {
 638         struct winbindd_child *child;
 639
 640         DEBUG(10,("winbind_msg_onlinestatus: got onlinestatus message.\n"));
 641
 642         for (child = children; child != NULL; child = child->next) {
 643                 if (child->domain && child->domain->primary) {
 644                         DEBUG(10,("winbind_msg_onlinestatus: "
 645                                   "sending message to pid %u of primary domain.\n",
 646                                   (unsigned int)child->pid));
 647                         messaging_send_buf(msg_ctx, pid_to_procid(child->pid),
 648                                            MSG_WINBIND_ONLINESTATUS,
 649                                            (uint8 *)data->data,
 650                                            data->length);
 651                         break;
 652                 }
 653         }
 654 }
 655
 656 void winbind_msg_dump_event_list(struct messaging_context *msg_ctx,
 657                                  void *private_data,
 658                                  uint32_t msg_type,
 659                                  struct server_id server_id,
 660                                  DATA_BLOB *data)
 661 {
 662         struct winbindd_child *child;
 663
 664         DEBUG(10,("winbind_msg_dump_event_list received\n"));
 665
 666         dump_event_list(winbind_event_context());
 667
 668         for (child = children; child != NULL; child = child->next) {
 669
 670                 DEBUG(10,("winbind_msg_dump_event_list: sending message to pid %u\n",
 671                         (unsigned int)child->pid));
 672
 673                 messaging_send_buf(msg_ctx, pid_to_procid(child->pid),
 674                                    MSG_DUMP_EVENT_LIST,
 675                                    NULL, 0);
 676         }
 677
 678 }
 679
 680 static void account_lockout_policy_handler(struct event_context *ctx,
 681                                            struct timed_event *te,
 682                                            const struct timeval *now,
 683                                            void *private_data)
 684 {
 685         struct winbindd_child *child =
 686                 (struct winbindd_child *)private_data;
 687         TALLOC_CTX *mem_ctx = NULL;
 688         struct winbindd_methods *methods;
 689         SAM_UNK_INFO_12 lockout_policy;
 690         NTSTATUS result;
 691
 692         DEBUG(10,("account_lockout_policy_handler called\n"));
 693
 694         TALLOC_FREE(child->lockout_policy_event);
 695
 696         if ( !winbindd_can_contact_domain( child->domain ) ) {
 697                 DEBUG(10,("account_lockout_policy_handler: Removing myself since I "
 698                           "do not have an incoming trust to domain %s\n",
 699                           child->domain->name));
 700
 701                 return;
 702         }
 703
 704         methods = child->domain->methods;
 705
 706         mem_ctx = talloc_init("account_lockout_policy_handler ctx");
 707         if (!mem_ctx) {
 708                 result = NT_STATUS_NO_MEMORY;
 709         } else {
 710                 result = methods->lockout_policy(child->domain, mem_ctx, &lockout_policy);
 711         }
 712         TALLOC_FREE(mem_ctx);
 713
 714         if (!NT_STATUS_IS_OK(result)) {
 715                 DEBUG(10,("account_lockout_policy_handler: lockout_policy failed error %s\n",
 716                          nt_errstr(result)));
 717         }
 718
 719         child->lockout_policy_event = event_add_timed(winbind_event_context(), NULL,
 720                                                       timeval_current_ofs(3600, 0),
 721                                                       "account_lockout_policy_handler",
 722                                                       account_lockout_policy_handler,
 723                                                       child);
 724 }
 725
 726 /* Deal with a request to go offline. */
 727
 728 static void child_msg_offline(struct messaging_context *msg,
 729                               void *private_data,
 730                               uint32_t msg_type,
 731                               struct server_id server_id,
 732                               DATA_BLOB *data)
 733 {
 734         struct winbindd_domain *domain;
 735         const char *domainname = (const char *)data->data;
 736
 737         if (data->data == NULL || data->length == 0) {
 738                 return;
 739         }
 740
 741         DEBUG(5,("child_msg_offline received for domain %s.\n", domainname));
 742
 743         if (!lp_winbind_offline_logon()) {
 744                 DEBUG(10,("child_msg_offline: rejecting offline message.\n"));
 745                 return;
 746         }
 747
 748         /* Mark the requested domain offline. */
 749
 750         for (domain = domain_list(); domain; domain = domain->next) {
 751                 if (domain->internal) {
 752                         continue;
 753                 }
 754                 if (strequal(domain->name, domainname)) {
 755                         DEBUG(5,("child_msg_offline: marking %s offline.\n", domain->name));
 756                         set_domain_offline(domain);
 757                 }
 758         }
 759 }
 760
 761 /* Deal with a request to go online. */
 762
 763 static void child_msg_online(struct messaging_context *msg,
 764                              void *private_data,
 765                              uint32_t msg_type,
 766                              struct server_id server_id,
 767                              DATA_BLOB *data)
 768 {
 769         struct winbindd_domain *domain;
 770         const char *domainname = (const char *)data->data;
 771
 772         if (data->data == NULL || data->length == 0) {
 773                 return;
 774         }
 775
 776         DEBUG(5,("child_msg_online received for domain %s.\n", domainname));
 777
 778         if (!lp_winbind_offline_logon()) {
 779                 DEBUG(10,("child_msg_online: rejecting online message.\n"));
 780                 return;
 781         }
 782
 783         /* Set our global state as online. */
 784         set_global_winbindd_state_online();
 785
 786         /* Try and mark everything online - delete any negative cache entries
 787            to force a reconnect now. */
 788
 789         for (domain = domain_list(); domain; domain = domain->next) {
 790                 if (domain->internal) {
 791                         continue;
 792                 }
 793                 if (strequal(domain->name, domainname)) {
 794                         DEBUG(5,("child_msg_online: requesting %s to go online.\n", domain->name));
 795                         winbindd_flush_negative_conn_cache(domain);
 796                         set_domain_online_request(domain);
 797                 }
 798         }
 799 }
 800
 801 static const char *collect_onlinestatus(TALLOC_CTX *mem_ctx)
 802 {
 803         struct winbindd_domain *domain;
 804         char *buf = NULL;
 805
 806         if ((buf = talloc_asprintf(mem_ctx, "global:%s ",
 807                                    get_global_winbindd_state_offline() ?
 808                                    "Offline":"Online")) == NULL) {
 809                 return NULL;
 810         }
 811
 812         for (domain = domain_list(); domain; domain = domain->next) {
 813                 if ((buf = talloc_asprintf_append_buffer(buf, "%s:%s ",
 814                                                   domain->name,
 815                                                   domain->online ?
 816                                                   "Online":"Offline")) == NULL) {
 817                         return NULL;
 818                 }
 819         }
 820
 821         buf = talloc_asprintf_append_buffer(buf, "\n");
 822
 823         DEBUG(5,("collect_onlinestatus: %s", buf));
 824
 825         return buf;
 826 }
 827
 828 static void child_msg_onlinestatus(struct messaging_context *msg_ctx,
 829                                    void *private_data,
 830                                    uint32_t msg_type,
 831                                    struct server_id server_id,
 832                                    DATA_BLOB *data)
 833 {
 834         TALLOC_CTX *mem_ctx;
 835         const char *message;
 836         struct server_id *sender;
 837
 838         DEBUG(5,("winbind_msg_onlinestatus received.\n"));
 839
 840         if (!data->data) {
 841                 return;
 842         }
 843
 844         sender = (struct server_id *)data->data;
 845
 846         mem_ctx = talloc_init("winbind_msg_onlinestatus");
 847         if (mem_ctx == NULL) {
 848                 return;
 849         }
 850
 851         message = collect_onlinestatus(mem_ctx);
 852         if (message == NULL) {
 853                 talloc_destroy(mem_ctx);
 854                 return;
 855         }
 856
 857         messaging_send_buf(msg_ctx, *sender, MSG_WINBIND_ONLINESTATUS,
 858                            (uint8 *)message, strlen(message) + 1);
 859
 860         talloc_destroy(mem_ctx);
 861 }
 862
 863 static void child_msg_dump_event_list(struct messaging_context *msg,
 864                                       void *private_data,
 865                                       uint32_t msg_type,
 866                                       struct server_id server_id,
 867                                       DATA_BLOB *data)
 868 {
 869         DEBUG(5,("child_msg_dump_event_list received\n"));
 870
 871         dump_event_list(winbind_event_context());
 872 }
 873
 874
 875 static bool fork_domain_child(struct winbindd_child *child)
 876 {
 877         int fdpair[2];
 878         struct winbindd_cli_state state;
 879         struct winbindd_domain *domain;
 880
 881         if (socketpair(AF_UNIX, SOCK_STREAM, 0, fdpair) != 0) {
 882                 DEBUG(0, ("Could not open child pipe: %s\n",
 883                           strerror(errno)));
 884                 return False;
 885         }
 886
 887         ZERO_STRUCT(state);
 888         state.pid = sys_getpid();
 889
 890         /* Stop zombies */
 891         CatchChild();
 892
 893         child->pid = sys_fork();
 894
 895         if (child->pid == -1) {
 896                 DEBUG(0, ("Could not fork: %s\n", strerror(errno)));
 897                 return False;
 898         }
 899
 900         if (child->pid != 0) {
 901                 /* Parent */
 902                 close(fdpair[0]);
 903                 child->next = child->prev = NULL;
 904                 DLIST_ADD(children, child);
 905                 child->event.fd = fdpair[1];
 906                 child->event.flags = 0;
 907                 child->requests = NULL;
 908                 add_fd_event(&child->event);
 909                 return True;
 910         }
 911
 912         /* Child */
 913
 914         state.sock = fdpair[0];
 915         close(fdpair[1]);
 916
 917         /* tdb needs special fork handling */
 918         if (tdb_reopen_all(1) == -1) {
 919                 DEBUG(0,("tdb_reopen_all failed.\n"));
 920                 _exit(0);
 921         }
 922
 923         close_conns_after_fork();
 924
 925         if (!override_logfile) {
 926                 lp_set_logfile(child->logfilename);
 927                 reopen_logs();
 928         }
 929
 930         /*
 931          * For clustering, we need to re-init our ctdbd connection after the
 932          * fork
 933          */
 934         if (!NT_STATUS_IS_OK(messaging_reinit(winbind_messaging_context())))
 935                 exit(1);
 936
 937         /* Don't handle the same messages as our parent. */
 938         messaging_deregister(winbind_messaging_context(),
 939                              MSG_SMB_CONF_UPDATED, NULL);
 940         messaging_deregister(winbind_messaging_context(),
 941                              MSG_SHUTDOWN, NULL);
 942         messaging_deregister(winbind_messaging_context(),
 943                              MSG_WINBIND_OFFLINE, NULL);
 944         messaging_deregister(winbind_messaging_context(),
 945                              MSG_WINBIND_ONLINE, NULL);
 946         messaging_deregister(winbind_messaging_context(),
 947                              MSG_WINBIND_ONLINESTATUS, NULL);
 948         messaging_deregister(winbind_messaging_context(),
 949                              MSG_DUMP_EVENT_LIST, NULL);
 950
 951         /* Handle online/offline messages. */
 952         messaging_register(winbind_messaging_context(), NULL,
 953                            MSG_WINBIND_OFFLINE, child_msg_offline);
 954         messaging_register(winbind_messaging_context(), NULL,
 955                            MSG_WINBIND_ONLINE, child_msg_online);
 956         messaging_register(winbind_messaging_context(), NULL,
 957                            MSG_WINBIND_ONLINESTATUS, child_msg_onlinestatus);
 958         messaging_register(winbind_messaging_context(), NULL,
 959                            MSG_DUMP_EVENT_LIST, child_msg_dump_event_list);
 960
 961         if ( child->domain ) {
 962                 child->domain->startup = True;
 963                 child->domain->startup_time = time(NULL);
 964         }
 965
 966         /* Ensure we have no pending check_online events other
 967            than one for this domain. */
 968
 969         for (domain = domain_list(); domain; domain = domain->next) {
 970                 if (domain != child->domain) {
 971                         TALLOC_FREE(domain->check_online_event);
 972                 }
 973         }
 974
 975         /* Ensure we're not handling an event inherited from
 976            our parent. */
 977
 978         cancel_named_event(winbind_event_context(),
 979                            "krb5_ticket_refresh_handler");
 980
 981         /* We might be in the idmap child...*/
 982         if (child->domain && !(child->domain->internal) &&
 983             lp_winbind_offline_logon()) {
 984
 985                 set_domain_online_request(child->domain);
 986
 987                 child->lockout_policy_event = event_add_timed(
 988                         winbind_event_context(), NULL, timeval_zero(),
 989                         "account_lockout_policy_handler",
 990                         account_lockout_policy_handler,
 991                         child);
 992         }
 993
 994         while (1) {
 995
 996                 int ret;
 997                 fd_set read_fds;
 998                 struct timeval t;
 999                 struct timeval *tp;
1000                 struct timeval now;
1001                 TALLOC_CTX *frame = talloc_stackframe();
1002
1003                 run_events(winbind_event_context(), 0, NULL, NULL);
1004
1005                 GetTimeOfDay(&now);
1006
1007                 if (child->domain && child->domain->startup &&
1008                                 (now.tv_sec > child->domain->startup_time + 30)) {
1009                         /* No longer in "startup" mode. */
1010                         DEBUG(10,("fork_domain_child: domain %s no longer in 'startup' mode.\n",
1011                                 child->domain->name ));
1012                         child->domain->startup = False;
1013                 }
1014
1015                 tp = get_timed_events_timeout(winbind_event_context(), &t);
1016                 if (tp) {
1017                         DEBUG(11,("select will use timeout of %u.%u seconds\n",
1018                                 (unsigned int)tp->tv_sec, (unsigned int)tp->tv_usec ));
1019                 }
1020
1021                 /* Handle messages */
1022
1023                 message_dispatch(winbind_messaging_context());
1024
1025                 FD_ZERO(&read_fds);
1026                 FD_SET(state.sock, &read_fds);
1027
1028                 ret = sys_select(state.sock + 1, &read_fds, NULL, NULL, tp);
1029
1030                 if (ret == 0) {
1031                         DEBUG(11,("nothing is ready yet, continue\n"));
1032                         TALLOC_FREE(frame);
1033                         continue;
1034                 }
1035
1036                 if (ret == -1 && errno == EINTR) {
1037                         /* We got a signal - continue. */
1038                         TALLOC_FREE(frame);
1039                         continue;
1040                 }
1041
1042                 if (ret == -1 && errno != EINTR) {
1043                         DEBUG(0,("select error occured\n"));
1044                         TALLOC_FREE(frame);
1045                         perror("select");
1046                         return False;
1047                 }
1048
1049                 /* fetch a request from the main daemon */
1050                 child_read_request(&state);
1051
1052                 if (state.finished) {
1053                         /* we lost contact with our parent */
1054                         exit(0);
1055                 }
1056
1057                 DEBUG(4,("child daemon request %d\n", (int)state.request.cmd));
1058
1059                 ZERO_STRUCT(state.response);
1060                 state.request.null_term = '\0';
1061                 child_process_request(child, &state);
1062
1063                 SAFE_FREE(state.request.extra_data.data);
1064
1065                 cache_store_response(sys_getpid(), &state.response);
1066
1067                 SAFE_FREE(state.response.extra_data.data);
1068
1069                 /* We just send the result code back, the result
1070                  * structure needs to be fetched via the
1071                  * winbindd_cache. Hmm. That needs fixing... */
1072
1073                 if (write_data(state.sock,
1074                                (const char *)&state.response.result,
1075                                sizeof(state.response.result)) !=
1076                     sizeof(state.response.result)) {
1077                         DEBUG(0, ("Could not write result\n"));
1078                         exit(1);
1079                 }
1080                 TALLOC_FREE(frame);
1081         }
1082 }