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 #include "rpc_client/rpc_client.h"
  33 #include "nsswitch/wb_reqtrans.h"
  34 #include "secrets.h"
  35 #include "../lib/util/select.h"
  36 #include "../libcli/security/security.h"
  37 #include "system/select.h"
  38 #include "messages.h"
  39 #include "../lib/util/tevent_unix.h"
  40 #include "lib/param/loadparm.h"
  41 #include "lib/util/sys_rw.h"
  42 #include "lib/util/sys_rw_data.h"
  43
  44 #undef DBGC_CLASS
  45 #define DBGC_CLASS DBGC_WINBIND
  46
  47 extern bool override_logfile;
  48
  49 static struct winbindd_child *winbindd_children = NULL;
  50
  51 /* Read some data from a client connection */
  52
  53 static NTSTATUS child_read_request(int sock, struct winbindd_request *wreq)
  54 {
  55         NTSTATUS status;
  56
  57         status = read_data_ntstatus(sock, (char *)wreq, sizeof(*wreq));
  58         if (!NT_STATUS_IS_OK(status)) {
  59                 DEBUG(3, ("child_read_request: read_data failed: %s\n",
  60                           nt_errstr(status)));
  61                 return status;
  62         }
  63
  64         if (wreq->extra_len == 0) {
  65                 wreq->extra_data.data = NULL;
  66                 return NT_STATUS_OK;
  67         }
  68
  69         DEBUG(10, ("Need to read %d extra bytes\n", (int)wreq->extra_len));
  70
  71         wreq->extra_data.data = SMB_MALLOC_ARRAY(char, wreq->extra_len + 1);
  72         if (wreq->extra_data.data == NULL) {
  73                 DEBUG(0, ("malloc failed\n"));
  74                 return NT_STATUS_NO_MEMORY;
  75         }
  76
  77         /* Ensure null termination */
  78         wreq->extra_data.data[wreq->extra_len] = '\0';
  79
  80         status = read_data_ntstatus(sock, wreq->extra_data.data,
  81                                     wreq->extra_len);
  82         if (!NT_STATUS_IS_OK(status)) {
  83                 DEBUG(0, ("Could not read extra data: %s\n",
  84                           nt_errstr(status)));
  85         }
  86         return status;
  87 }
  88
  89 static NTSTATUS child_write_response(int sock, struct winbindd_response *wrsp)
  90 {
  91         struct iovec iov[2];
  92         int iov_count;
  93
  94         iov[0].iov_base = (void *)wrsp;
  95         iov[0].iov_len = sizeof(struct winbindd_response);
  96         iov_count = 1;
  97
  98         if (wrsp->length > sizeof(struct winbindd_response)) {
  99                 iov[1].iov_base = (void *)wrsp->extra_data.data;
 100                 iov[1].iov_len = wrsp->length-iov[0].iov_len;
 101                 iov_count = 2;
 102         }
 103
 104         DEBUG(10, ("Writing %d bytes to parent\n", (int)wrsp->length));
 105
 106         if (write_data_iov(sock, iov, iov_count) != wrsp->length) {
 107                 DEBUG(0, ("Could not write result\n"));
 108                 return NT_STATUS_INVALID_HANDLE;
 109         }
 110
 111         return NT_STATUS_OK;
 112 }
 113
 114 /*
 115  * Do winbind child async request. This is not simply wb_simple_trans. We have
 116  * to do the queueing ourselves because while a request is queued, the child
 117  * might have crashed, and we have to re-fork it in the _trigger function.
 118  */
 119
 120 struct wb_child_request_state {
 121         struct tevent_context *ev;
 122         struct tevent_req *queue_subreq;
 123         struct tevent_req *subreq;
 124         struct winbindd_child *child;
 125         struct winbindd_request *request;
 126         struct winbindd_response *response;
 127 };
 128
 129 static bool fork_domain_child(struct winbindd_child *child);
 130
 131 static void wb_child_request_waited(struct tevent_req *subreq);
 132 static void wb_child_request_done(struct tevent_req *subreq);
 133 static void wb_child_request_orphaned(struct tevent_req *subreq);
 134
 135 static void wb_child_request_cleanup(struct tevent_req *req,
 136                                      enum tevent_req_state req_state);
 137
 138 struct tevent_req *wb_child_request_send(TALLOC_CTX *mem_ctx,
 139                                          struct tevent_context *ev,
 140                                          struct winbindd_child *child,
 141                                          struct winbindd_request *request)
 142 {
 143         struct tevent_req *req;
 144         struct wb_child_request_state *state;
 145         struct tevent_req *subreq;
 146
 147         req = tevent_req_create(mem_ctx, &state,
 148                                 struct wb_child_request_state);
 149         if (req == NULL) {
 150                 return NULL;
 151         }
 152
 153         state->ev = ev;
 154         state->child = child;
 155         state->request = request;
 156
 157         subreq = tevent_queue_wait_send(state, ev, child->queue);
 158         if (tevent_req_nomem(subreq, req)) {
 159                 return tevent_req_post(req, ev);
 160         }
 161         tevent_req_set_callback(subreq, wb_child_request_waited, req);
 162         state->queue_subreq = subreq;
 163
 164         tevent_req_set_cleanup_fn(req, wb_child_request_cleanup);
 165
 166         return req;
 167 }
 168
 169 static void wb_child_request_waited(struct tevent_req *subreq)
 170 {
 171         struct tevent_req *req = tevent_req_callback_data(
 172                 subreq, struct tevent_req);
 173         struct wb_child_request_state *state = tevent_req_data(
 174                 req, struct wb_child_request_state);
 175         bool ok;
 176
 177         ok = tevent_queue_wait_recv(subreq);
 178         if (!ok) {
 179                 tevent_req_oom(req);
 180                 return;
 181         }
 182         /*
 183          * We need to keep state->queue_subreq
 184          * in order to block the queue.
 185          */
 186         subreq = NULL;
 187
 188         if ((state->child->sock == -1) && (!fork_domain_child(state->child))) {
 189                 tevent_req_error(req, errno);
 190                 return;
 191         }
 192
 193         subreq = wb_simple_trans_send(state, server_event_context(), NULL,
 194                                       state->child->sock, state->request);
 195         if (tevent_req_nomem(subreq, req)) {
 196                 return;
 197         }
 198
 199         state->subreq = subreq;
 200         tevent_req_set_callback(subreq, wb_child_request_done, req);
 201         tevent_req_set_endtime(req, state->ev, timeval_current_ofs(300, 0));
 202 }
 203
 204 static void wb_child_request_done(struct tevent_req *subreq)
 205 {
 206         struct tevent_req *req = tevent_req_callback_data(
 207                 subreq, struct tevent_req);
 208         struct wb_child_request_state *state = tevent_req_data(
 209                 req, struct wb_child_request_state);
 210         int ret, err;
 211
 212         ret = wb_simple_trans_recv(subreq, state, &state->response, &err);
 213         /* Freeing the subrequest is deferred until the cleanup function,
 214          * which has to know whether a subrequest exists, and consequently
 215          * decide whether to shut down the pipe to the child process.
 216          */
 217         if (ret == -1) {
 218                 tevent_req_error(req, err);
 219                 return;
 220         }
 221         tevent_req_done(req);
 222 }
 223
 224 static void wb_child_request_orphaned(struct tevent_req *subreq)
 225 {
 226         DBG_WARNING("cleanup orphaned subreq[%p]\n", subreq);
 227         TALLOC_FREE(subreq);
 228 }
 229
 230 int wb_child_request_recv(struct tevent_req *req, TALLOC_CTX *mem_ctx,
 231                           struct winbindd_response **presponse, int *err)
 232 {
 233         struct wb_child_request_state *state = tevent_req_data(
 234                 req, struct wb_child_request_state);
 235
 236         if (tevent_req_is_unix_error(req, err)) {
 237                 return -1;
 238         }
 239         *presponse = talloc_move(mem_ctx, &state->response);
 240         return 0;
 241 }
 242
 243 static void wb_child_request_cleanup(struct tevent_req *req,
 244                                      enum tevent_req_state req_state)
 245 {
 246         struct wb_child_request_state *state =
 247             tevent_req_data(req, struct wb_child_request_state);
 248
 249         if (state->subreq == NULL) {
 250                 /* nothing to cleanup */
 251                 return;
 252         }
 253
 254         if (req_state == TEVENT_REQ_RECEIVED) {
 255                 struct tevent_req *subreq = NULL;
 256
 257                 /*
 258                  * Our caller gave up, but we need to keep
 259                  * the low level request (wb_simple_trans)
 260                  * in order to maintain the parent child protocol.
 261                  *
 262                  * We also need to keep the child queue blocked
 263                  * until we got the response from the child.
 264                  */
 265
 266                 subreq = talloc_move(state->child->queue, &state->subreq);
 267                 talloc_move(subreq, &state->queue_subreq);
 268                 tevent_req_set_callback(subreq,
 269                                         wb_child_request_orphaned,
 270                                         NULL);
 271
 272                 DBG_WARNING("keep orphaned subreq[%p]\n", subreq);
 273                 return;
 274         }
 275
 276         TALLOC_FREE(state->subreq);
 277         TALLOC_FREE(state->queue_subreq);
 278
 279         if (req_state == TEVENT_REQ_DONE) {
 280                 /* transmitted request and got response */
 281                 return;
 282         }
 283
 284         /*
 285          * Failed to transmit and receive response, or request
 286          * cancelled while being serviced.
 287          * The basic parent/child communication broke, close
 288          * our socket
 289          */
 290         close(state->child->sock);
 291         state->child->sock = -1;
 292         DLIST_REMOVE(winbindd_children, state->child);
 293 }
 294
 295 static struct winbindd_child *choose_domain_child(struct winbindd_domain *domain)
 296 {
 297         struct winbindd_child *shortest = &domain->children[0];
 298         struct winbindd_child *current;
 299         int i;
 300
 301         for (i=0; i<lp_winbind_max_domain_connections(); i++) {
 302                 size_t shortest_len, current_len;
 303
 304                 current = &domain->children[i];
 305                 current_len = tevent_queue_length(current->queue);
 306
 307                 if (current_len == 0) {
 308                         /* idle child */
 309                         return current;
 310                 }
 311
 312                 shortest_len = tevent_queue_length(shortest->queue);
 313
 314                 if (current_len < shortest_len) {
 315                         shortest = current;
 316                 }
 317         }
 318
 319         return shortest;
 320 }
 321
 322 struct dcerpc_binding_handle *dom_child_handle(struct winbindd_domain *domain)
 323 {
 324         return domain->binding_handle;
 325 }
 326
 327 struct wb_domain_request_state {
 328         struct tevent_context *ev;
 329         struct winbindd_domain *domain;
 330         struct winbindd_child *child;
 331         struct winbindd_request *request;
 332         struct winbindd_request *init_req;
 333         struct winbindd_response *response;
 334 };
 335
 336 static void wb_domain_request_gotdc(struct tevent_req *subreq);
 337 static void wb_domain_request_initialized(struct tevent_req *subreq);
 338 static void wb_domain_request_done(struct tevent_req *subreq);
 339
 340 struct tevent_req *wb_domain_request_send(TALLOC_CTX *mem_ctx,
 341                                           struct tevent_context *ev,
 342                                           struct winbindd_domain *domain,
 343                                           struct winbindd_request *request)
 344 {
 345         struct tevent_req *req, *subreq;
 346         struct wb_domain_request_state *state;
 347
 348         req = tevent_req_create(mem_ctx, &state,
 349                                 struct wb_domain_request_state);
 350         if (req == NULL) {
 351                 return NULL;
 352         }
 353
 354         state->domain = domain;
 355         state->ev = ev;
 356         state->request = request;
 357
 358         state->child = choose_domain_child(domain);
 359
 360         if (domain->initialized) {
 361                 subreq = wb_child_request_send(state, state->ev, state->child,
 362                                                state->request);
 363                 if (tevent_req_nomem(subreq, req)) {
 364                         return tevent_req_post(req, ev);
 365                 }
 366                 tevent_req_set_callback(subreq, wb_domain_request_done, req);
 367                 return req;
 368         }
 369
 370         state->init_req = talloc_zero(state, struct winbindd_request);
 371         if (tevent_req_nomem(state->init_req, req)) {
 372                 return tevent_req_post(req, ev);
 373         }
 374
 375         if (IS_DC || domain->primary || domain->internal) {
 376                 /* The primary domain has to find the DC name itself */
 377                 state->init_req->cmd = WINBINDD_INIT_CONNECTION;
 378                 fstrcpy(state->init_req->domain_name, domain->name);
 379                 state->init_req->data.init_conn.is_primary = domain->primary;
 380                 fstrcpy(state->init_req->data.init_conn.dcname, "");
 381
 382                 subreq = wb_child_request_send(state, state->ev, state->child,
 383                                                state->init_req);
 384                 if (tevent_req_nomem(subreq, req)) {
 385                         return tevent_req_post(req, ev);
 386                 }
 387                 tevent_req_set_callback(subreq, wb_domain_request_initialized,
 388                                         req);
 389                 return req;
 390         }
 391
 392         /*
 393          * This is *not* the primary domain,
 394          * let's ask our DC about a DC name.
 395          *
 396          * We prefer getting a dns name in dc_unc,
 397          * which is indicated by DS_RETURN_DNS_NAME.
 398          * For NT4 domains we still get the netbios name.
 399          */
 400         subreq = wb_dsgetdcname_send(state, state->ev,
 401                                      state->domain->name,
 402                                      NULL, /* domain_guid */
 403                                      NULL, /* site_name */
 404                                      DS_RETURN_DNS_NAME); /* flags */
 405         if (tevent_req_nomem(subreq, req)) {
 406                 return tevent_req_post(req, ev);
 407         }
 408         tevent_req_set_callback(subreq, wb_domain_request_gotdc, req);
 409         return req;
 410 }
 411
 412 static void wb_domain_request_gotdc(struct tevent_req *subreq)
 413 {
 414         struct tevent_req *req = tevent_req_callback_data(
 415                 subreq, struct tevent_req);
 416         struct wb_domain_request_state *state = tevent_req_data(
 417                 req, struct wb_domain_request_state);
 418         struct netr_DsRGetDCNameInfo *dcinfo = NULL;
 419         NTSTATUS status;
 420         const char *dcname = NULL;
 421
 422         status = wb_dsgetdcname_recv(subreq, state, &dcinfo);
 423         TALLOC_FREE(subreq);
 424         if (tevent_req_nterror(req, status)) {
 425                 return;
 426         }
 427         dcname = dcinfo->dc_unc;
 428         while (dcname != NULL && *dcname == '\\') {
 429                 dcname++;
 430         }
 431         state->init_req->cmd = WINBINDD_INIT_CONNECTION;
 432         fstrcpy(state->init_req->domain_name, state->domain->name);
 433         state->init_req->data.init_conn.is_primary = False;
 434         fstrcpy(state->init_req->data.init_conn.dcname,
 435                 dcname);
 436
 437         TALLOC_FREE(dcinfo);
 438
 439         subreq = wb_child_request_send(state, state->ev, state->child,
 440                                        state->init_req);
 441         if (tevent_req_nomem(subreq, req)) {
 442                 return;
 443         }
 444         tevent_req_set_callback(subreq, wb_domain_request_initialized, req);
 445 }
 446
 447 static void wb_domain_request_initialized(struct tevent_req *subreq)
 448 {
 449         struct tevent_req *req = tevent_req_callback_data(
 450                 subreq, struct tevent_req);
 451         struct wb_domain_request_state *state = tevent_req_data(
 452                 req, struct wb_domain_request_state);
 453         struct winbindd_response *response;
 454         int ret, err;
 455
 456         ret = wb_child_request_recv(subreq, talloc_tos(), &response, &err);
 457         TALLOC_FREE(subreq);
 458         if (ret == -1) {
 459                 tevent_req_error(req, err);
 460                 return;
 461         }
 462
 463         if (!string_to_sid(&state->domain->sid,
 464                            response->data.domain_info.sid)) {
 465                 DEBUG(1,("init_child_recv: Could not convert sid %s "
 466                         "from string\n", response->data.domain_info.sid));
 467                 tevent_req_error(req, EINVAL);
 468                 return;
 469         }
 470
 471         talloc_free(state->domain->name);
 472         state->domain->name = talloc_strdup(state->domain,
 473                                             response->data.domain_info.name);
 474         if (state->domain->name == NULL) {
 475                 tevent_req_error(req, ENOMEM);
 476                 return;
 477         }
 478
 479         if (response->data.domain_info.alt_name[0] != '\0') {
 480                 talloc_free(state->domain->alt_name);
 481
 482                 state->domain->alt_name = talloc_strdup(state->domain,
 483                                 response->data.domain_info.alt_name);
 484                 if (state->domain->alt_name == NULL) {
 485                         tevent_req_error(req, ENOMEM);
 486                         return;
 487                 }
 488         }
 489
 490         state->domain->native_mode = response->data.domain_info.native_mode;
 491         state->domain->active_directory =
 492                 response->data.domain_info.active_directory;
 493         state->domain->initialized = true;
 494
 495         TALLOC_FREE(response);
 496
 497         subreq = wb_child_request_send(state, state->ev, state->child,
 498                                        state->request);
 499         if (tevent_req_nomem(subreq, req)) {
 500                 return;
 501         }
 502         tevent_req_set_callback(subreq, wb_domain_request_done, req);
 503 }
 504
 505 static void wb_domain_request_done(struct tevent_req *subreq)
 506 {
 507         struct tevent_req *req = tevent_req_callback_data(
 508                 subreq, struct tevent_req);
 509         struct wb_domain_request_state *state = tevent_req_data(
 510                 req, struct wb_domain_request_state);
 511         int ret, err;
 512
 513         ret = wb_child_request_recv(subreq, talloc_tos(), &state->response,
 514                                     &err);
 515         TALLOC_FREE(subreq);
 516         if (ret == -1) {
 517                 tevent_req_error(req, err);
 518                 return;
 519         }
 520         tevent_req_done(req);
 521 }
 522
 523 int wb_domain_request_recv(struct tevent_req *req, TALLOC_CTX *mem_ctx,
 524                            struct winbindd_response **presponse, int *err)
 525 {
 526         struct wb_domain_request_state *state = tevent_req_data(
 527                 req, struct wb_domain_request_state);
 528
 529         if (tevent_req_is_unix_error(req, err)) {
 530                 return -1;
 531         }
 532         *presponse = talloc_move(mem_ctx, &state->response);
 533         return 0;
 534 }
 535
 536 static void child_process_request(struct winbindd_child *child,
 537                                   struct winbindd_cli_state *state)
 538 {
 539         struct winbindd_domain *domain = child->domain;
 540         const struct winbindd_child_dispatch_table *table = child->table;
 541
 542         /* Free response data - we may be interrupted and receive another
 543            command before being able to send this data off. */
 544
 545         state->response->result = WINBINDD_ERROR;
 546         state->response->length = sizeof(struct winbindd_response);
 547
 548         /* as all requests in the child are sync, we can use talloc_tos() */
 549         state->mem_ctx = talloc_tos();
 550
 551         /* Process command */
 552
 553         for (; table->name; table++) {
 554                 if (state->request->cmd == table->struct_cmd) {
 555                         DEBUG(10,("child_process_request: request fn %s\n",
 556                                   table->name));
 557                         state->response->result = table->struct_fn(domain, state);
 558                         return;
 559                 }
 560         }
 561
 562         DEBUG(1, ("child_process_request: unknown request fn number %d\n",
 563                   (int)state->request->cmd));
 564         state->response->result = WINBINDD_ERROR;
 565 }
 566
 567 void setup_child(struct winbindd_domain *domain, struct winbindd_child *child,
 568                  const struct winbindd_child_dispatch_table *table,
 569                  const char *logprefix,
 570                  const char *logname)
 571 {
 572         if (logprefix && logname) {
 573                 char *logbase = NULL;
 574
 575                 if (*lp_logfile(talloc_tos())) {
 576                         char *end = NULL;
 577
 578                         if (asprintf(&logbase, "%s", lp_logfile(talloc_tos())) < 0) {
 579                                 smb_panic("Internal error: asprintf failed");
 580                         }
 581
 582                         if ((end = strrchr_m(logbase, '/'))) {
 583                                 *end = '\0';
 584                         }
 585                 } else {
 586                         if (asprintf(&logbase, "%s", get_dyn_LOGFILEBASE()) < 0) {
 587                                 smb_panic("Internal error: asprintf failed");
 588                         }
 589                 }
 590
 591                 if (asprintf(&child->logfilename, "%s/%s-%s",
 592                              logbase, logprefix, logname) < 0) {
 593                         SAFE_FREE(logbase);
 594                         smb_panic("Internal error: asprintf failed");
 595                 }
 596
 597                 SAFE_FREE(logbase);
 598         } else {
 599                 smb_panic("Internal error: logprefix == NULL && "
 600                           "logname == NULL");
 601         }
 602
 603         child->sock = -1;
 604         child->domain = domain;
 605         child->table = table;
 606         child->queue = tevent_queue_create(NULL, "winbind_child");
 607         SMB_ASSERT(child->queue != NULL);
 608         if (domain == NULL) {
 609                 child->binding_handle = wbint_binding_handle(NULL, NULL, child);
 610                 SMB_ASSERT(child->binding_handle != NULL);
 611         }
 612 }
 613
 614 void winbind_child_died(pid_t pid)
 615 {
 616         struct winbindd_child *child;
 617
 618         for (child = winbindd_children; child != NULL; child = child->next) {
 619                 if (child->pid == pid) {
 620                         break;
 621                 }
 622         }
 623
 624         if (child == NULL) {
 625                 DEBUG(5, ("Already reaped child %u died\n", (unsigned int)pid));
 626                 return;
 627         }
 628
 629         /* This will be re-added in fork_domain_child() */
 630
 631         DLIST_REMOVE(winbindd_children, child);
 632         child->pid = 0;
 633
 634         if (child->sock != -1) {
 635                 close(child->sock);
 636                 child->sock = -1;
 637         }
 638 }
 639
 640 /* Ensure any negative cache entries with the netbios or realm names are removed. */
 641
 642 void winbindd_flush_negative_conn_cache(struct winbindd_domain *domain)
 643 {
 644         flush_negative_conn_cache_for_domain(domain->name);
 645         if (domain->alt_name != NULL) {
 646                 flush_negative_conn_cache_for_domain(domain->alt_name);
 647         }
 648 }
 649
 650 /*
 651  * Parent winbindd process sets its own debug level first and then
 652  * sends a message to all the winbindd children to adjust their debug
 653  * level to that of parents.
 654  */
 655
 656 void winbind_msg_debug(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_debug: got debug message.\n"));
 665
 666         debug_message(msg_ctx, private_data, MSG_DEBUG, server_id, data);
 667
 668         for (child = winbindd_children; child != NULL; child = child->next) {
 669
 670                 DEBUG(10,("winbind_msg_debug: 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_DEBUG,
 675                            data->data,
 676                            strlen((char *) data->data) + 1);
 677         }
 678 }
 679
 680 /* Set our domains as offline and forward the offline message to our children. */
 681
 682 void winbind_msg_offline(struct messaging_context *msg_ctx,
 683                          void *private_data,
 684                          uint32_t msg_type,
 685                          struct server_id server_id,
 686                          DATA_BLOB *data)
 687 {
 688         struct winbindd_child *child;
 689         struct winbindd_domain *domain;
 690
 691         DEBUG(10,("winbind_msg_offline: got offline message.\n"));
 692
 693         if (!lp_winbind_offline_logon()) {
 694                 DEBUG(10,("winbind_msg_offline: rejecting offline message.\n"));
 695                 return;
 696         }
 697
 698         /* Set our global state as offline. */
 699         if (!set_global_winbindd_state_offline()) {
 700                 DEBUG(10,("winbind_msg_offline: offline request failed.\n"));
 701                 return;
 702         }
 703
 704         /* Set all our domains as offline. */
 705         for (domain = domain_list(); domain; domain = domain->next) {
 706                 if (domain->internal) {
 707                         continue;
 708                 }
 709                 DEBUG(5,("winbind_msg_offline: marking %s offline.\n", domain->name));
 710                 set_domain_offline(domain);
 711         }
 712
 713         for (child = winbindd_children; child != NULL; child = child->next) {
 714                 /* Don't send message to internal children.  We've already
 715                    done so above. */
 716                 if (!child->domain || winbindd_internal_child(child)) {
 717                         continue;
 718                 }
 719
 720                 /* Or internal domains (this should not be possible....) */
 721                 if (child->domain->internal) {
 722                         continue;
 723                 }
 724
 725                 /* Each winbindd child should only process requests for one domain - make sure
 726                    we only set it online / offline for that domain. */
 727
 728                 DEBUG(10,("winbind_msg_offline: sending message to pid %u for domain %s.\n",
 729                         (unsigned int)child->pid, child->domain->name ));
 730
 731                 messaging_send_buf(msg_ctx, pid_to_procid(child->pid),
 732                                    MSG_WINBIND_OFFLINE,
 733                                    (const uint8_t *)child->domain->name,
 734                                    strlen(child->domain->name)+1);
 735         }
 736 }
 737
 738 /* Set our domains as online and forward the online message to our children. */
 739
 740 void winbind_msg_online(struct messaging_context *msg_ctx,
 741                         void *private_data,
 742                         uint32_t msg_type,
 743                         struct server_id server_id,
 744                         DATA_BLOB *data)
 745 {
 746         struct winbindd_child *child;
 747         struct winbindd_domain *domain;
 748
 749         DEBUG(10,("winbind_msg_online: got online message.\n"));
 750
 751         if (!lp_winbind_offline_logon()) {
 752                 DEBUG(10,("winbind_msg_online: rejecting online message.\n"));
 753                 return;
 754         }
 755
 756         /* Set our global state as online. */
 757         set_global_winbindd_state_online();
 758
 759         smb_nscd_flush_user_cache();
 760         smb_nscd_flush_group_cache();
 761
 762         /* Set all our domains as online. */
 763         for (domain = domain_list(); domain; domain = domain->next) {
 764                 if (domain->internal) {
 765                         continue;
 766                 }
 767                 DEBUG(5,("winbind_msg_online: requesting %s to go online.\n", domain->name));
 768
 769                 winbindd_flush_negative_conn_cache(domain);
 770                 set_domain_online_request(domain);
 771
 772                 /* Send an online message to the idmap child when our
 773                    primary domain comes back online */
 774
 775                 if ( domain->primary ) {
 776                         struct winbindd_child *idmap = idmap_child();
 777
 778                         if ( idmap->pid != 0 ) {
 779                                 messaging_send_buf(msg_ctx,
 780                                                    pid_to_procid(idmap->pid),
 781                                                    MSG_WINBIND_ONLINE,
 782                                                    (const uint8_t *)domain->name,
 783                                                    strlen(domain->name)+1);
 784                         }
 785                 }
 786         }
 787
 788         for (child = winbindd_children; child != NULL; child = child->next) {
 789                 /* Don't send message to internal childs. */
 790                 if (!child->domain || winbindd_internal_child(child)) {
 791                         continue;
 792                 }
 793
 794                 /* Or internal domains (this should not be possible....) */
 795                 if (child->domain->internal) {
 796                         continue;
 797                 }
 798
 799                 /* Each winbindd child should only process requests for one domain - make sure
 800                    we only set it online / offline for that domain. */
 801
 802                 DEBUG(10,("winbind_msg_online: sending message to pid %u for domain %s.\n",
 803                         (unsigned int)child->pid, child->domain->name ));
 804
 805                 messaging_send_buf(msg_ctx, pid_to_procid(child->pid),
 806                                    MSG_WINBIND_ONLINE,
 807                                    (const uint8_t *)child->domain->name,
 808                                    strlen(child->domain->name)+1);
 809         }
 810 }
 811
 812 static const char *collect_onlinestatus(TALLOC_CTX *mem_ctx)
 813 {
 814         struct winbindd_domain *domain;
 815         char *buf = NULL;
 816
 817         if ((buf = talloc_asprintf(mem_ctx, "global:%s ",
 818                                    get_global_winbindd_state_offline() ?
 819                                    "Offline":"Online")) == NULL) {
 820                 return NULL;
 821         }
 822
 823         for (domain = domain_list(); domain; domain = domain->next) {
 824                 if ((buf = talloc_asprintf_append_buffer(buf, "%s:%s ",
 825                                                   domain->name,
 826                                                   domain->online ?
 827                                                   "Online":"Offline")) == NULL) {
 828                         return NULL;
 829                 }
 830         }
 831
 832         buf = talloc_asprintf_append_buffer(buf, "\n");
 833
 834         DEBUG(5,("collect_onlinestatus: %s", buf));
 835
 836         return buf;
 837 }
 838
 839 void winbind_msg_onlinestatus(struct messaging_context *msg_ctx,
 840                               void *private_data,
 841                               uint32_t msg_type,
 842                               struct server_id server_id,
 843                               DATA_BLOB *data)
 844 {
 845         TALLOC_CTX *mem_ctx;
 846         const char *message;
 847
 848         DEBUG(5,("winbind_msg_onlinestatus received.\n"));
 849
 850         mem_ctx = talloc_init("winbind_msg_onlinestatus");
 851         if (mem_ctx == NULL) {
 852                 return;
 853         }
 854
 855         message = collect_onlinestatus(mem_ctx);
 856         if (message == NULL) {
 857                 talloc_destroy(mem_ctx);
 858                 return;
 859         }
 860
 861         messaging_send_buf(msg_ctx, server_id, MSG_WINBIND_ONLINESTATUS,
 862                            (const uint8_t *)message, strlen(message) + 1);
 863
 864         talloc_destroy(mem_ctx);
 865 }
 866
 867 void winbind_msg_dump_event_list(struct messaging_context *msg_ctx,
 868                                  void *private_data,
 869                                  uint32_t msg_type,
 870                                  struct server_id server_id,
 871                                  DATA_BLOB *data)
 872 {
 873         struct winbindd_child *child;
 874
 875         DEBUG(10,("winbind_msg_dump_event_list received\n"));
 876
 877         DBG_WARNING("dump event list no longer implemented\n");
 878
 879         for (child = winbindd_children; child != NULL; child = child->next) {
 880
 881                 DEBUG(10,("winbind_msg_dump_event_list: sending message to pid %u\n",
 882                         (unsigned int)child->pid));
 883
 884                 messaging_send_buf(msg_ctx, pid_to_procid(child->pid),
 885                                    MSG_DUMP_EVENT_LIST,
 886                                    NULL, 0);
 887         }
 888
 889 }
 890
 891 void winbind_msg_dump_domain_list(struct messaging_context *msg_ctx,
 892                                   void *private_data,
 893                                   uint32_t msg_type,
 894                                   struct server_id server_id,
 895                                   DATA_BLOB *data)
 896 {
 897         TALLOC_CTX *mem_ctx;
 898         const char *message = NULL;
 899         const char *domain = NULL;
 900         char *s = NULL;
 901         NTSTATUS status;
 902         struct winbindd_domain *dom = NULL;
 903
 904         DEBUG(5,("winbind_msg_dump_domain_list received.\n"));
 905
 906         mem_ctx = talloc_init("winbind_msg_dump_domain_list");
 907         if (!mem_ctx) {
 908                 return;
 909         }
 910
 911         if (data->length > 0) {
 912                 domain = (const char *)data->data;
 913         }
 914
 915         if (domain) {
 916
 917                 DEBUG(5,("winbind_msg_dump_domain_list for domain: %s\n",
 918                         domain));
 919
 920                 message = NDR_PRINT_STRUCT_STRING(mem_ctx, winbindd_domain,
 921                                                   find_domain_from_name_noinit(domain));
 922                 if (!message) {
 923                         talloc_destroy(mem_ctx);
 924                         return;
 925                 }
 926
 927                 messaging_send_buf(msg_ctx, server_id,
 928                                    MSG_WINBIND_DUMP_DOMAIN_LIST,
 929                                    (const uint8_t *)message, strlen(message) + 1);
 930
 931                 talloc_destroy(mem_ctx);
 932
 933                 return;
 934         }
 935
 936         DEBUG(5,("winbind_msg_dump_domain_list all domains\n"));
 937
 938         for (dom = domain_list(); dom; dom=dom->next) {
 939                 message = NDR_PRINT_STRUCT_STRING(mem_ctx, winbindd_domain, dom);
 940                 if (!message) {
 941                         talloc_destroy(mem_ctx);
 942                         return;
 943                 }
 944
 945                 s = talloc_asprintf_append(s, "%s\n", message);
 946                 if (!s) {
 947                         talloc_destroy(mem_ctx);
 948                         return;
 949                 }
 950         }
 951
 952         status = messaging_send_buf(msg_ctx, server_id,
 953                                     MSG_WINBIND_DUMP_DOMAIN_LIST,
 954                                     (uint8_t *)s, strlen(s) + 1);
 955         if (!NT_STATUS_IS_OK(status)) {
 956                 DEBUG(0,("failed to send message: %s\n",
 957                 nt_errstr(status)));
 958         }
 959
 960         talloc_destroy(mem_ctx);
 961 }
 962
 963 static void account_lockout_policy_handler(struct tevent_context *ctx,
 964                                            struct tevent_timer *te,
 965                                            struct timeval now,
 966                                            void *private_data)
 967 {
 968         struct winbindd_child *child =
 969                 (struct winbindd_child *)private_data;
 970         TALLOC_CTX *mem_ctx = NULL;
 971         struct samr_DomInfo12 lockout_policy;
 972         NTSTATUS result;
 973
 974         DEBUG(10,("account_lockout_policy_handler called\n"));
 975
 976         TALLOC_FREE(child->lockout_policy_event);
 977
 978         if ( !winbindd_can_contact_domain( child->domain ) ) {
 979                 DEBUG(10,("account_lockout_policy_handler: Removing myself since I "
 980                           "do not have an incoming trust to domain %s\n",
 981                           child->domain->name));
 982
 983                 return;
 984         }
 985
 986         mem_ctx = talloc_init("account_lockout_policy_handler ctx");
 987         if (!mem_ctx) {
 988                 result = NT_STATUS_NO_MEMORY;
 989         } else {
 990                 result = wb_cache_lockout_policy(child->domain, mem_ctx,
 991                                                  &lockout_policy);
 992         }
 993         TALLOC_FREE(mem_ctx);
 994
 995         if (!NT_STATUS_IS_OK(result)) {
 996                 DEBUG(10,("account_lockout_policy_handler: lockout_policy failed error %s\n",
 997                          nt_errstr(result)));
 998         }
 999
1000         child->lockout_policy_event = tevent_add_timer(server_event_context(), NULL,
1001                                                       timeval_current_ofs(3600, 0),
1002                                                       account_lockout_policy_handler,
1003                                                       child);
1004 }
1005
1006 static time_t get_machine_password_timeout(void)
1007 {
1008         /* until we have gpo support use lp setting */
1009         return lp_machine_password_timeout();
1010 }
1011
1012 static bool calculate_next_machine_pwd_change(const char *domain,
1013                                               struct timeval *t)
1014 {
1015         time_t pass_last_set_time;
1016         time_t timeout;
1017         time_t next_change;
1018         struct timeval tv;
1019         char *pw;
1020
1021         pw = secrets_fetch_machine_password(domain,
1022                                             &pass_last_set_time,
1023                                             NULL);
1024
1025         if (pw == NULL) {
1026                 DEBUG(0,("cannot fetch own machine password ????"));
1027                 return false;
1028         }
1029
1030         SAFE_FREE(pw);
1031
1032         timeout = get_machine_password_timeout();
1033         if (timeout == 0) {
1034                 DEBUG(10,("machine password never expires\n"));
1035                 return false;
1036         }
1037
1038         tv.tv_sec = pass_last_set_time;
1039         DEBUG(10, ("password last changed %s\n",
1040                    timeval_string(talloc_tos(), &tv, false)));
1041         tv.tv_sec += timeout;
1042         DEBUGADD(10, ("password valid until %s\n",
1043                       timeval_string(talloc_tos(), &tv, false)));
1044
1045         if (time(NULL) < (pass_last_set_time + timeout)) {
1046                 next_change = pass_last_set_time + timeout;
1047                 DEBUG(10,("machine password still valid until: %s\n",
1048                         http_timestring(talloc_tos(), next_change)));
1049                 *t = timeval_set(next_change, 0);
1050
1051                 if (lp_clustering()) {
1052                         uint8_t randbuf;
1053                         /*
1054                          * When having a cluster, we have several
1055                          * winbinds racing for the password change. In
1056                          * the machine_password_change_handler()
1057                          * function we check if someone else was
1058                          * faster when the event triggers. We add a
1059                          * 255-second random delay here, so that we
1060                          * don't run to change the password at the
1061                          * exact same moment.
1062                          */
1063                         generate_random_buffer(&randbuf, sizeof(randbuf));
1064                         DEBUG(10, ("adding %d seconds randomness\n",
1065                                    (int)randbuf));
1066                         t->tv_sec += randbuf;
1067                 }
1068                 return true;
1069         }
1070
1071         DEBUG(10,("machine password expired, needs immediate change\n"));
1072
1073         *t = timeval_zero();
1074
1075         return true;
1076 }
1077
1078 static void machine_password_change_handler(struct tevent_context *ctx,
1079                                             struct tevent_timer *te,
1080                                             struct timeval now,
1081                                             void *private_data)
1082 {
1083         struct messaging_context *msg_ctx = server_messaging_context();
1084         struct winbindd_child *child =
1085                 (struct winbindd_child *)private_data;
1086         struct rpc_pipe_client *netlogon_pipe = NULL;
1087         struct netlogon_creds_cli_context *netlogon_creds_ctx = NULL;
1088         NTSTATUS result;
1089         struct timeval next_change;
1090
1091         DEBUG(10,("machine_password_change_handler called\n"));
1092
1093         TALLOC_FREE(child->machine_password_change_event);
1094
1095         if (!calculate_next_machine_pwd_change(child->domain->name,
1096                                                &next_change)) {
1097                 DEBUG(10, ("calculate_next_machine_pwd_change failed\n"));
1098                 return;
1099         }
1100
1101         DEBUG(10, ("calculate_next_machine_pwd_change returned %s\n",
1102                    timeval_string(talloc_tos(), &next_change, false)));
1103
1104         if (!timeval_expired(&next_change)) {
1105                 DEBUG(10, ("Someone else has already changed the pw\n"));
1106                 goto done;
1107         }
1108
1109         if (!winbindd_can_contact_domain(child->domain)) {
1110                 DEBUG(10,("machine_password_change_handler: Removing myself since I "
1111                           "do not have an incoming trust to domain %s\n",
1112                           child->domain->name));
1113                 return;
1114         }
1115
1116         result = cm_connect_netlogon_secure(child->domain,
1117                                             &netlogon_pipe,
1118                                             &netlogon_creds_ctx);
1119         if (!NT_STATUS_IS_OK(result)) {
1120                 DEBUG(10,("machine_password_change_handler: "
1121                         "failed to connect netlogon pipe: %s\n",
1122                          nt_errstr(result)));
1123                 return;
1124         }
1125
1126         result = trust_pw_change(netlogon_creds_ctx,
1127                                  msg_ctx,
1128                                  netlogon_pipe->binding_handle,
1129                                  child->domain->name,
1130                                  child->domain->dcname,
1131                                  false); /* force */
1132
1133         DEBUG(10, ("machine_password_change_handler: "
1134                    "trust_pw_change returned %s\n",
1135                    nt_errstr(result)));
1136
1137         if (NT_STATUS_EQUAL(result, NT_STATUS_ACCESS_DENIED) ) {
1138                 DEBUG(3,("machine_password_change_handler: password set returned "
1139                          "ACCESS_DENIED.  Maybe the trust account "
1140                          "password was changed and we didn't know it. "
1141                          "Killing connections to domain %s\n",
1142                          child->domain->name));
1143                 invalidate_cm_connection(child->domain);
1144         }
1145
1146         if (!calculate_next_machine_pwd_change(child->domain->name,
1147                                                &next_change)) {
1148                 DEBUG(10, ("calculate_next_machine_pwd_change failed\n"));
1149                 return;
1150         }
1151
1152         DEBUG(10, ("calculate_next_machine_pwd_change returned %s\n",
1153                    timeval_string(talloc_tos(), &next_change, false)));
1154
1155         if (!NT_STATUS_IS_OK(result)) {
1156                 struct timeval tmp;
1157                 /*
1158                  * In case of failure, give the DC a minute to recover
1159                  */
1160                 tmp = timeval_current_ofs(60, 0);
1161                 next_change = timeval_max(&next_change, &tmp);
1162         }
1163
1164 done:
1165         child->machine_password_change_event = tevent_add_timer(server_event_context(), NULL,
1166                                                               next_change,
1167                                                               machine_password_change_handler,
1168                                                               child);
1169 }
1170
1171 /* Deal with a request to go offline. */
1172
1173 static void child_msg_offline(struct messaging_context *msg,
1174                               void *private_data,
1175                               uint32_t msg_type,
1176                               struct server_id server_id,
1177                               DATA_BLOB *data)
1178 {
1179         struct winbindd_domain *domain;
1180         struct winbindd_domain *primary_domain = NULL;
1181         const char *domainname = (const char *)data->data;
1182
1183         if (data->data == NULL || data->length == 0) {
1184                 return;
1185         }
1186
1187         DEBUG(5,("child_msg_offline received for domain %s.\n", domainname));
1188
1189         if (!lp_winbind_offline_logon()) {
1190                 DEBUG(10,("child_msg_offline: rejecting offline message.\n"));
1191                 return;
1192         }
1193
1194         primary_domain = find_our_domain();
1195
1196         /* Mark the requested domain offline. */
1197
1198         for (domain = domain_list(); domain; domain = domain->next) {
1199                 if (domain->internal) {
1200                         continue;
1201                 }
1202                 if (strequal(domain->name, domainname)) {
1203                         DEBUG(5,("child_msg_offline: marking %s offline.\n", domain->name));
1204                         set_domain_offline(domain);
1205                         /* we are in the trusted domain, set the primary domain
1206                          * offline too */
1207                         if (domain != primary_domain) {
1208                                 set_domain_offline(primary_domain);
1209                         }
1210                 }
1211         }
1212 }
1213
1214 /* Deal with a request to go online. */
1215
1216 static void child_msg_online(struct messaging_context *msg,
1217                              void *private_data,
1218                              uint32_t msg_type,
1219                              struct server_id server_id,
1220                              DATA_BLOB *data)
1221 {
1222         struct winbindd_domain *domain;
1223         struct winbindd_domain *primary_domain = NULL;
1224         const char *domainname = (const char *)data->data;
1225
1226         if (data->data == NULL || data->length == 0) {
1227                 return;
1228         }
1229
1230         DEBUG(5,("child_msg_online received for domain %s.\n", domainname));
1231
1232         if (!lp_winbind_offline_logon()) {
1233                 DEBUG(10,("child_msg_online: rejecting online message.\n"));
1234                 return;
1235         }
1236
1237         primary_domain = find_our_domain();
1238
1239         /* Set our global state as online. */
1240         set_global_winbindd_state_online();
1241
1242         /* Try and mark everything online - delete any negative cache entries
1243            to force a reconnect now. */
1244
1245         for (domain = domain_list(); domain; domain = domain->next) {
1246                 if (domain->internal) {
1247                         continue;
1248                 }
1249                 if (strequal(domain->name, domainname)) {
1250                         DEBUG(5,("child_msg_online: requesting %s to go online.\n", domain->name));
1251                         winbindd_flush_negative_conn_cache(domain);
1252                         set_domain_online_request(domain);
1253
1254                         /* we can be in trusted domain, which will contact primary domain
1255                          * we have to bring primary domain online in trusted domain process
1256                          * see, winbindd_dual_pam_auth() --> winbindd_dual_pam_auth_samlogon()
1257                          * --> contact_domain = find_our_domain()
1258                          * */
1259                         if (domain != primary_domain) {
1260                                 winbindd_flush_negative_conn_cache(primary_domain);
1261                                 set_domain_online_request(primary_domain);
1262                         }
1263                 }
1264         }
1265 }
1266
1267 static void child_msg_dump_event_list(struct messaging_context *msg,
1268                                       void *private_data,
1269                                       uint32_t msg_type,
1270                                       struct server_id server_id,
1271                                       DATA_BLOB *data)
1272 {
1273         DEBUG(5,("child_msg_dump_event_list received\n"));
1274         DBG_WARNING("dump_event_list no longer implemented\n");
1275 }
1276
1277 NTSTATUS winbindd_reinit_after_fork(const struct winbindd_child *myself,
1278                                     const char *logfilename)
1279 {
1280         struct winbindd_domain *domain;
1281         struct winbindd_child *cl;
1282         NTSTATUS status;
1283
1284         status = reinit_after_fork(
1285                 server_messaging_context(),
1286                 server_event_context(),
1287                 true, NULL);
1288         if (!NT_STATUS_IS_OK(status)) {
1289                 DEBUG(0,("reinit_after_fork() failed\n"));
1290                 return status;
1291         }
1292
1293         close_conns_after_fork();
1294
1295         if (!override_logfile && logfilename) {
1296                 lp_set_logfile(logfilename);
1297                 reopen_logs();
1298         }
1299
1300         if (!winbindd_setup_sig_term_handler(false))
1301                 return NT_STATUS_NO_MEMORY;
1302         if (!winbindd_setup_sig_hup_handler(override_logfile ? NULL :
1303                                             logfilename))
1304                 return NT_STATUS_NO_MEMORY;
1305
1306         /* Stop zombies in children */
1307         CatchChild();
1308
1309         /* Don't handle the same messages as our parent. */
1310         messaging_deregister(server_messaging_context(),
1311                              MSG_SMB_CONF_UPDATED, NULL);
1312         messaging_deregister(server_messaging_context(),
1313                              MSG_SHUTDOWN, NULL);
1314         messaging_deregister(server_messaging_context(),
1315                              MSG_WINBIND_OFFLINE, NULL);
1316         messaging_deregister(server_messaging_context(),
1317                              MSG_WINBIND_ONLINE, NULL);
1318         messaging_deregister(server_messaging_context(),
1319                              MSG_WINBIND_ONLINESTATUS, NULL);
1320         messaging_deregister(server_messaging_context(),
1321                              MSG_DUMP_EVENT_LIST, NULL);
1322         messaging_deregister(server_messaging_context(),
1323                              MSG_WINBIND_DUMP_DOMAIN_LIST, NULL);
1324         messaging_deregister(server_messaging_context(),
1325                              MSG_DEBUG, NULL);
1326
1327         messaging_deregister(server_messaging_context(),
1328                              MSG_WINBIND_DOMAIN_OFFLINE, NULL);
1329         messaging_deregister(server_messaging_context(),
1330                              MSG_WINBIND_DOMAIN_ONLINE, NULL);
1331
1332         /* We have destroyed all events in the winbindd_event_context
1333          * in reinit_after_fork(), so clean out all possible pending
1334          * event pointers. */
1335
1336         /* Deal with check_online_events. */
1337
1338         for (domain = domain_list(); domain; domain = domain->next) {
1339                 TALLOC_FREE(domain->check_online_event);
1340         }
1341
1342         /* Ensure we're not handling a credential cache event inherited
1343          * from our parent. */
1344
1345         ccache_remove_all_after_fork();
1346
1347         /* Destroy all possible events in child list. */
1348         for (cl = winbindd_children; cl != NULL; cl = cl->next) {
1349                 TALLOC_FREE(cl->lockout_policy_event);
1350                 TALLOC_FREE(cl->machine_password_change_event);
1351
1352                 /* Children should never be able to send
1353                  * each other messages, all messages must
1354                  * go through the parent.
1355                  */
1356                 cl->pid = (pid_t)0;
1357
1358                 /*
1359                  * Close service sockets to all other children
1360                  */
1361                 if ((cl != myself) && (cl->sock != -1)) {
1362                         close(cl->sock);
1363                         cl->sock = -1;
1364                 }
1365         }
1366         /*
1367          * This is a little tricky, children must not
1368          * send an MSG_WINBIND_ONLINE message to idmap_child().
1369          * If we are in a child of our primary domain or
1370          * in the process created by fork_child_dc_connect(),
1371          * and the primary domain cannot go online,
1372          * fork_child_dc_connection() sends MSG_WINBIND_ONLINE
1373          * periodically to idmap_child().
1374          *
1375          * The sequence is, fork_child_dc_connect() ---> getdcs() --->
1376          * get_dc_name_via_netlogon() ---> cm_connect_netlogon()
1377          * ---> init_dc_connection() ---> cm_open_connection --->
1378          * set_domain_online(), sends MSG_WINBIND_ONLINE to
1379          * idmap_child(). Disallow children sending messages
1380          * to each other, all messages must go through the parent.
1381          */
1382         cl = idmap_child();
1383         cl->pid = (pid_t)0;
1384
1385         return NT_STATUS_OK;
1386 }
1387
1388 /*
1389  * In a child there will be only one domain, reference that here.
1390  */
1391 static struct winbindd_domain *child_domain;
1392
1393 struct winbindd_domain *wb_child_domain(void)
1394 {
1395         return child_domain;
1396 }
1397
1398 struct child_handler_state {
1399         struct winbindd_child *child;
1400         struct winbindd_cli_state cli;
1401 };
1402
1403 static void child_handler(struct tevent_context *ev, struct tevent_fd *fde,
1404                           uint16_t flags, void *private_data)
1405 {
1406         struct child_handler_state *state =
1407                 (struct child_handler_state *)private_data;
1408         NTSTATUS status;
1409
1410         /* fetch a request from the main daemon */
1411         status = child_read_request(state->cli.sock, state->cli.request);
1412
1413         if (!NT_STATUS_IS_OK(status)) {
1414                 /* we lost contact with our parent */
1415                 _exit(0);
1416         }
1417
1418         DEBUG(4,("child daemon request %d\n",
1419                  (int)state->cli.request->cmd));
1420
1421         ZERO_STRUCTP(state->cli.response);
1422         state->cli.request->null_term = '\0';
1423         state->cli.mem_ctx = talloc_tos();
1424         child_process_request(state->child, &state->cli);
1425
1426         DEBUG(4, ("Finished processing child request %d\n",
1427                   (int)state->cli.request->cmd));
1428
1429         SAFE_FREE(state->cli.request->extra_data.data);
1430
1431         status = child_write_response(state->cli.sock, state->cli.response);
1432         if (!NT_STATUS_IS_OK(status)) {
1433                 exit(1);
1434         }
1435 }
1436
1437 static bool fork_domain_child(struct winbindd_child *child)
1438 {
1439         int fdpair[2];
1440         struct child_handler_state state;
1441         struct winbindd_request request;
1442         struct winbindd_response response;
1443         struct winbindd_domain *primary_domain = NULL;
1444         NTSTATUS status;
1445         ssize_t nwritten;
1446         struct tevent_fd *fde;
1447
1448         if (child->domain) {
1449                 DEBUG(10, ("fork_domain_child called for domain '%s'\n",
1450                            child->domain->name));
1451         } else {
1452                 DEBUG(10, ("fork_domain_child called without domain.\n"));
1453         }
1454
1455         if (socketpair(AF_UNIX, SOCK_STREAM, 0, fdpair) != 0) {
1456                 DEBUG(0, ("Could not open child pipe: %s\n",
1457                           strerror(errno)));
1458                 return False;
1459         }
1460
1461         ZERO_STRUCT(state);
1462         state.child = child;
1463         state.cli.pid = getpid();
1464         state.cli.request = &request;
1465         state.cli.response = &response;
1466
1467         child->pid = fork();
1468
1469         if (child->pid == -1) {
1470                 DEBUG(0, ("Could not fork: %s\n", strerror(errno)));
1471                 close(fdpair[0]);
1472                 close(fdpair[1]);
1473                 return False;
1474         }
1475
1476         if (child->pid != 0) {
1477                 /* Parent */
1478                 ssize_t nread;
1479
1480                 close(fdpair[0]);
1481
1482                 nread = sys_read(fdpair[1], &status, sizeof(status));
1483                 if (nread != sizeof(status)) {
1484                         DEBUG(1, ("fork_domain_child: Could not read child status: "
1485                                   "nread=%d, error=%s\n", (int)nread,
1486                                   strerror(errno)));
1487                         close(fdpair[1]);
1488                         return false;
1489                 }
1490                 if (!NT_STATUS_IS_OK(status)) {
1491                         DEBUG(1, ("fork_domain_child: Child status is %s\n",
1492                                   nt_errstr(status)));
1493                         close(fdpair[1]);
1494                         return false;
1495                 }
1496
1497                 child->next = child->prev = NULL;
1498                 DLIST_ADD(winbindd_children, child);
1499                 child->sock = fdpair[1];
1500                 return True;
1501         }
1502
1503         /* Child */
1504         child_domain = child->domain;
1505
1506         DEBUG(10, ("Child process %d\n", (int)getpid()));
1507
1508         state.cli.sock = fdpair[0];
1509         close(fdpair[1]);
1510
1511         status = winbindd_reinit_after_fork(child, child->logfilename);
1512
1513         nwritten = sys_write(state.cli.sock, &status, sizeof(status));
1514         if (nwritten != sizeof(status)) {
1515                 DEBUG(1, ("fork_domain_child: Could not write status: "
1516                           "nwritten=%d, error=%s\n", (int)nwritten,
1517                           strerror(errno)));
1518                 _exit(0);
1519         }
1520         if (!NT_STATUS_IS_OK(status)) {
1521                 DEBUG(1, ("winbindd_reinit_after_fork failed: %s\n",
1522                           nt_errstr(status)));
1523                 _exit(0);
1524         }
1525
1526         if (child_domain != NULL) {
1527                 setproctitle("domain child [%s]", child_domain->name);
1528         } else if (child == idmap_child()) {
1529                 setproctitle("idmap child");
1530         }
1531
1532         /* Handle online/offline messages. */
1533         messaging_register(server_messaging_context(), NULL,
1534                            MSG_WINBIND_OFFLINE, child_msg_offline);
1535         messaging_register(server_messaging_context(), NULL,
1536                            MSG_WINBIND_ONLINE, child_msg_online);
1537         messaging_register(server_messaging_context(), NULL,
1538                            MSG_DUMP_EVENT_LIST, child_msg_dump_event_list);
1539         messaging_register(server_messaging_context(), NULL,
1540                            MSG_DEBUG, debug_message);
1541         messaging_register(server_messaging_context(), NULL,
1542                            MSG_WINBIND_IP_DROPPED,
1543                            winbind_msg_ip_dropped);
1544
1545
1546         primary_domain = find_our_domain();
1547
1548         if (primary_domain == NULL) {
1549                 smb_panic("no primary domain found");
1550         }
1551
1552         /* It doesn't matter if we allow cache login,
1553          * try to bring domain online after fork. */
1554         if ( child->domain ) {
1555                 child->domain->startup = True;
1556                 child->domain->startup_time = time_mono(NULL);
1557                 /* we can be in primary domain or in trusted domain
1558                  * If we are in trusted domain, set the primary domain
1559                  * in start-up mode */
1560                 if (!(child->domain->internal)) {
1561                         set_domain_online_request(child->domain);
1562                         if (!(child->domain->primary)) {
1563                                 primary_domain->startup = True;
1564                                 primary_domain->startup_time = time_mono(NULL);
1565                                 set_domain_online_request(primary_domain);
1566                         }
1567                 }
1568         }
1569
1570         /*
1571          * We are in idmap child, make sure that we set the
1572          * check_online_event to bring primary domain online.
1573          */
1574         if (child == idmap_child()) {
1575                 set_domain_online_request(primary_domain);
1576         }
1577
1578         /* We might be in the idmap child...*/
1579         if (child->domain && !(child->domain->internal) &&
1580             lp_winbind_offline_logon()) {
1581
1582                 set_domain_online_request(child->domain);
1583
1584                 if (primary_domain && (primary_domain != child->domain)) {
1585                         /* We need to talk to the primary
1586                          * domain as well as the trusted
1587                          * domain inside a trusted domain
1588                          * child.
1589                          * See the code in :
1590                          * set_dc_type_and_flags_trustinfo()
1591                          * for details.
1592                          */
1593                         set_domain_online_request(primary_domain);
1594                 }
1595
1596                 child->lockout_policy_event = tevent_add_timer(
1597                         server_event_context(), NULL, timeval_zero(),
1598                         account_lockout_policy_handler,
1599                         child);
1600         }
1601
1602         if (child->domain && child->domain->primary &&
1603             !USE_KERBEROS_KEYTAB &&
1604             lp_server_role() == ROLE_DOMAIN_MEMBER) {
1605
1606                 struct timeval next_change;
1607
1608                 if (calculate_next_machine_pwd_change(child->domain->name,
1609                                                        &next_change)) {
1610                         child->machine_password_change_event = tevent_add_timer(
1611                                 server_event_context(), NULL, next_change,
1612                                 machine_password_change_handler,
1613                                 child);
1614                 }
1615         }
1616
1617         fde = tevent_add_fd(server_event_context(), NULL, state.cli.sock,
1618                             TEVENT_FD_READ, child_handler, &state);
1619         if (fde == NULL) {
1620                 DEBUG(1, ("tevent_add_fd failed\n"));
1621                 _exit(1);
1622         }
1623
1624         while (1) {
1625
1626                 int ret;
1627                 TALLOC_CTX *frame = talloc_stackframe();
1628
1629                 ret = tevent_loop_once(server_event_context());
1630                 if (ret != 0) {
1631                         DEBUG(1, ("tevent_loop_once failed: %s\n",
1632                                   strerror(errno)));
1633                         _exit(1);
1634                 }
1635
1636                 if (child->domain && child->domain->startup &&
1637                                 (time_mono(NULL) > child->domain->startup_time + 30)) {
1638                         /* No longer in "startup" mode. */
1639                         DEBUG(10,("fork_domain_child: domain %s no longer in 'startup' mode.\n",
1640                                 child->domain->name ));
1641                         child->domain->startup = False;
1642                 }
1643
1644                 TALLOC_FREE(frame);
1645         }
1646 }
1647
1648 void winbind_msg_ip_dropped_parent(struct messaging_context *msg_ctx,
1649                                    void *private_data,
1650                                    uint32_t msg_type,
1651                                    struct server_id server_id,
1652                                    DATA_BLOB *data)
1653 {
1654         struct winbindd_child *child;
1655
1656         winbind_msg_ip_dropped(msg_ctx, private_data, msg_type,
1657                                server_id, data);
1658
1659
1660         for (child = winbindd_children; child != NULL; child = child->next) {
1661                 messaging_send_buf(msg_ctx, pid_to_procid(child->pid),
1662                                    msg_type, data->data, data->length);
1663         }
1664 }