source3/smbd/blocking.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Blocking Locking functions
   4    Copyright (C) Jeremy Allison 1998-2003
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "includes.h"
  21 #include "smbd/globals.h"
  22
  23 #undef DBGC_CLASS
  24 #define DBGC_CLASS DBGC_LOCKING
  25
  26 /****************************************************************************
  27  This is the structure to queue to implement blocking locks.
  28  notify. It consists of the requesting SMB and the expiry time.
  29 *****************************************************************************/
  30
  31 typedef struct blocking_lock_record {
  32         struct blocking_lock_record *next;
  33         struct blocking_lock_record *prev;
  34         files_struct *fsp;
  35         struct timeval expire_time;
  36         int lock_num;
  37         uint64_t offset;
  38         uint64_t count;
  39         uint32_t lock_pid;
  40         uint32_t blocking_pid; /* PID that blocks us. */
  41         enum brl_flavour lock_flav;
  42         enum brl_type lock_type;
  43         struct smb_request *req;
  44 } blocking_lock_record;
  45
  46 /****************************************************************************
  47  Determine if this is a secondary element of a chained SMB.
  48   **************************************************************************/
  49
  50 static bool in_chained_smb(void)
  51 {
  52         return (chain_size != 0);
  53 }
  54
  55 static void received_unlock_msg(struct messaging_context *msg,
  56                                 void *private_data,
  57                                 uint32_t msg_type,
  58                                 struct server_id server_id,
  59                                 DATA_BLOB *data);
  60 static void process_blocking_lock_queue(void);
  61
  62 static void brl_timeout_fn(struct event_context *event_ctx,
  63                            struct timed_event *te,
  64                            struct timeval now,
  65                            void *private_data)
  66 {
  67         SMB_ASSERT(brl_timeout == te);
  68         TALLOC_FREE(brl_timeout);
  69
  70         change_to_root_user();  /* TODO: Possibly run all timed events as
  71                                  * root */
  72
  73         process_blocking_lock_queue();
  74 }
  75
  76 /****************************************************************************
  77  After a change to blocking_lock_queue, recalculate the timed_event for the
  78  next processing.
  79 ****************************************************************************/
  80
  81 static bool recalc_brl_timeout(void)
  82 {
  83         blocking_lock_record *brl;
  84         struct timeval next_timeout;
  85
  86         TALLOC_FREE(brl_timeout);
  87
  88         next_timeout = timeval_zero();
  89
  90         for (brl = blocking_lock_queue; brl; brl = brl->next) {
  91                 if (timeval_is_zero(&brl->expire_time)) {
  92                         /*
  93                          * If we're blocked on pid 0xFFFFFFFF this is
  94                          * a POSIX lock, so calculate a timeout of
  95                          * 10 seconds into the future.
  96                          */
  97                         if (brl->blocking_pid == 0xFFFFFFFF) {
  98                                 struct timeval psx_to = timeval_current_ofs(10, 0);
  99                                 next_timeout = timeval_min(&next_timeout, &psx_to);
 100                         }
 101
 102                         continue;
 103                 }
 104
 105                 if (timeval_is_zero(&next_timeout)) {
 106                         next_timeout = brl->expire_time;
 107                 }
 108                 else {
 109                         next_timeout = timeval_min(&next_timeout,
 110                                                    &brl->expire_time);
 111                 }
 112         }
 113
 114         if (timeval_is_zero(&next_timeout)) {
 115                 return True;
 116         }
 117
 118         if (!(brl_timeout = event_add_timed(smbd_event_context(), NULL,
 119                                             next_timeout,
 120                                             brl_timeout_fn, NULL))) {
 121                 return False;
 122         }
 123
 124         return True;
 125 }
 126
 127
 128 /****************************************************************************
 129  Function to push a blocking lock request onto the lock queue.
 130 ****************************************************************************/
 131
 132 bool push_blocking_lock_request( struct byte_range_lock *br_lck,
 133                 struct smb_request *req,
 134                 files_struct *fsp,
 135                 int lock_timeout,
 136                 int lock_num,
 137                 uint32_t lock_pid,
 138                 enum brl_type lock_type,
 139                 enum brl_flavour lock_flav,
 140                 uint64_t offset,
 141                 uint64_t count,
 142                 uint32_t blocking_pid)
 143 {
 144         blocking_lock_record *blr;
 145         NTSTATUS status;
 146
 147         if(in_chained_smb() ) {
 148                 DEBUG(0,("push_blocking_lock_request: cannot queue a chained request (currently).\n"));
 149                 return False;
 150         }
 151
 152         /*
 153          * Now queue an entry on the blocking lock queue. We setup
 154          * the expiration time here.
 155          */
 156
 157         blr = talloc(NULL, struct blocking_lock_record);
 158         if (blr == NULL) {
 159                 DEBUG(0,("push_blocking_lock_request: Malloc fail !\n" ));
 160                 return False;
 161         }
 162
 163         blr->next = NULL;
 164         blr->prev = NULL;
 165
 166         blr->fsp = fsp;
 167         if (lock_timeout == -1) {
 168                 blr->expire_time.tv_sec = 0;
 169                 blr->expire_time.tv_usec = 0; /* Never expire. */
 170         } else {
 171                 blr->expire_time = timeval_current_ofs(lock_timeout/1000,
 172                                         (lock_timeout % 1000) * 1000);
 173         }
 174         blr->lock_num = lock_num;
 175         blr->lock_pid = lock_pid;
 176         blr->blocking_pid = blocking_pid;
 177         blr->lock_flav = lock_flav;
 178         blr->lock_type = lock_type;
 179         blr->offset = offset;
 180         blr->count = count;
 181
 182         /* Add a pending lock record for this. */
 183         status = brl_lock(smbd_messaging_context(), br_lck,
 184                         lock_pid,
 185                         procid_self(),
 186                         offset,
 187                         count,
 188                         lock_type == READ_LOCK ? PENDING_READ_LOCK : PENDING_WRITE_LOCK,
 189                         blr->lock_flav,
 190                         lock_timeout ? True : False, /* blocking_lock. */
 191                         NULL);
 192
 193         if (!NT_STATUS_IS_OK(status)) {
 194                 DEBUG(0,("push_blocking_lock_request: failed to add PENDING_LOCK record.\n"));
 195                 DLIST_REMOVE(blocking_lock_queue, blr);
 196                 TALLOC_FREE(blr);
 197                 return False;
 198         }
 199
 200         blr->req = talloc_move(blr, &req);
 201
 202         DLIST_ADD_END(blocking_lock_queue, blr, blocking_lock_record *);
 203         recalc_brl_timeout();
 204
 205         /* Ensure we'll receive messages when this is unlocked. */
 206         if (!blocking_lock_unlock_state) {
 207                 messaging_register(smbd_messaging_context(), NULL,
 208                                    MSG_SMB_UNLOCK, received_unlock_msg);
 209                 blocking_lock_unlock_state = true;
 210         }
 211
 212         DEBUG(3,("push_blocking_lock_request: lock request blocked with "
 213                 "expiry time (%u sec. %u usec) (+%d msec) for fnum = %d, name = %s\n",
 214                 (unsigned int)blr->expire_time.tv_sec,
 215                 (unsigned int)blr->expire_time.tv_usec, lock_timeout,
 216                 blr->fsp->fnum, blr->fsp->fsp_name ));
 217
 218         /* Push the MID of this packet on the signing queue. */
 219         srv_defer_sign_response(blr->req->mid);
 220
 221         return True;
 222 }
 223
 224 /****************************************************************************
 225  Return a lockingX success SMB.
 226 *****************************************************************************/
 227
 228 static void reply_lockingX_success(blocking_lock_record *blr)
 229 {
 230         reply_outbuf(blr->req, 2, 0);
 231
 232         /*
 233          * As this message is a lockingX call we must handle
 234          * any following chained message correctly.
 235          * This is normally handled in construct_reply(),
 236          * but as that calls switch_message, we can't use
 237          * that here and must set up the chain info manually.
 238          */
 239
 240         chain_reply(blr->req);
 241         TALLOC_FREE(blr->req->outbuf);
 242 }
 243
 244 /****************************************************************************
 245  Return a generic lock fail error blocking call.
 246 *****************************************************************************/
 247
 248 static void generic_blocking_lock_error(blocking_lock_record *blr, NTSTATUS status)
 249 {
 250         /* whenever a timeout is given w2k maps LOCK_NOT_GRANTED to
 251            FILE_LOCK_CONFLICT! (tridge) */
 252         if (NT_STATUS_EQUAL(status, NT_STATUS_LOCK_NOT_GRANTED)) {
 253                 status = NT_STATUS_FILE_LOCK_CONFLICT;
 254         }
 255
 256         if (NT_STATUS_EQUAL(status, NT_STATUS_FILE_LOCK_CONFLICT)) {
 257                 /* Store the last lock error. */
 258                 files_struct *fsp = blr->fsp;
 259
 260                 if (fsp) {
 261                         fsp->last_lock_failure.context.smbpid = blr->lock_pid;
 262                         fsp->last_lock_failure.context.tid = fsp->conn->cnum;
 263                         fsp->last_lock_failure.context.pid = procid_self();
 264                         fsp->last_lock_failure.start = blr->offset;
 265                         fsp->last_lock_failure.size = blr->count;
 266                         fsp->last_lock_failure.fnum = fsp->fnum;
 267                         fsp->last_lock_failure.lock_type = READ_LOCK; /* Don't care. */
 268                         fsp->last_lock_failure.lock_flav = blr->lock_flav;
 269                 }
 270         }
 271
 272         reply_nterror(blr->req, status);
 273         if (!srv_send_smb(smbd_server_fd(), (char *)blr->req->outbuf,
 274                           blr->req->encrypted)) {
 275                 exit_server_cleanly("generic_blocking_lock_error: srv_send_smb failed.");
 276         }
 277         TALLOC_FREE(blr->req->outbuf);
 278 }
 279
 280 /****************************************************************************
 281  Return a lock fail error for a lockingX call. Undo all the locks we have
 282  obtained first.
 283 *****************************************************************************/
 284
 285 static void reply_lockingX_error(blocking_lock_record *blr, NTSTATUS status)
 286 {
 287         files_struct *fsp = blr->fsp;
 288         uint16 num_ulocks = SVAL(blr->req->vwv+6, 0);
 289         uint64_t count = (uint64_t)0, offset = (uint64_t) 0;
 290         uint32 lock_pid;
 291         unsigned char locktype = CVAL(blr->req->vwv+3, 0);
 292         bool large_file_format = (locktype & LOCKING_ANDX_LARGE_FILES);
 293         uint8_t *data;
 294         int i;
 295
 296         data = (uint8_t *)blr->req->buf
 297                 + ((large_file_format ? 20 : 10)*num_ulocks);
 298
 299         /*
 300          * Data now points at the beginning of the list
 301          * of smb_lkrng structs.
 302          */
 303
 304         /*
 305          * Ensure we don't do a remove on the lock that just failed,
 306          * as under POSIX rules, if we have a lock already there, we
 307          * will delete it (and we shouldn't) .....
 308          */
 309
 310         for(i = blr->lock_num - 1; i >= 0; i--) {
 311                 bool err;
 312
 313                 lock_pid = get_lock_pid( data, i, large_file_format);
 314                 count = get_lock_count( data, i, large_file_format);
 315                 offset = get_lock_offset( data, i, large_file_format, &err);
 316
 317                 /*
 318                  * We know err cannot be set as if it was the lock
 319                  * request would never have been queued. JRA.
 320                  */
 321
 322                 do_unlock(smbd_messaging_context(),
 323                         fsp,
 324                         lock_pid,
 325                         count,
 326                         offset,
 327                         WINDOWS_LOCK);
 328         }
 329
 330         generic_blocking_lock_error(blr, status);
 331 }
 332
 333 /****************************************************************************
 334  Return a lock fail error.
 335 *****************************************************************************/
 336
 337 static void blocking_lock_reply_error(blocking_lock_record *blr, NTSTATUS status)
 338 {
 339         switch(blr->req->cmd) {
 340         case SMBlockingX:
 341                 reply_lockingX_error(blr, status);
 342                 break;
 343         case SMBtrans2:
 344         case SMBtranss2:
 345                 reply_nterror(blr->req, status);
 346
 347                 /*
 348                  * construct_reply_common has done us the favor to pre-fill
 349                  * the command field with SMBtranss2 which is wrong :-)
 350                  */
 351                 SCVAL(blr->req->outbuf,smb_com,SMBtrans2);
 352
 353                 if (!srv_send_smb(smbd_server_fd(),
 354                                   (char *)blr->req->outbuf,
 355                                   IS_CONN_ENCRYPTED(blr->fsp->conn))) {
 356                         exit_server_cleanly("blocking_lock_reply_error: "
 357                                             "srv_send_smb failed.");
 358                 }
 359                 TALLOC_FREE(blr->req->outbuf);
 360                 break;
 361         default:
 362                 DEBUG(0,("blocking_lock_reply_error: PANIC - unknown type on blocking lock queue - exiting.!\n"));
 363                 exit_server("PANIC - unknown type on blocking lock queue");
 364         }
 365 }
 366
 367 /****************************************************************************
 368  Attempt to finish off getting all pending blocking locks for a lockingX call.
 369  Returns True if we want to be removed from the list.
 370 *****************************************************************************/
 371
 372 static bool process_lockingX(blocking_lock_record *blr)
 373 {
 374         unsigned char locktype = CVAL(blr->req->vwv+3, 0);
 375         files_struct *fsp = blr->fsp;
 376         uint16 num_ulocks = SVAL(blr->req->vwv+6, 0);
 377         uint16 num_locks = SVAL(blr->req->vwv+7, 0);
 378         uint64_t count = (uint64_t)0, offset = (uint64_t)0;
 379         uint32 lock_pid;
 380         bool large_file_format = (locktype & LOCKING_ANDX_LARGE_FILES);
 381         uint8_t *data;
 382         NTSTATUS status = NT_STATUS_OK;
 383
 384         data = (uint8_t *)blr->req->buf
 385                 + ((large_file_format ? 20 : 10)*num_ulocks);
 386
 387         /*
 388          * Data now points at the beginning of the list
 389          * of smb_lkrng structs.
 390          */
 391
 392         for(; blr->lock_num < num_locks; blr->lock_num++) {
 393                 struct byte_range_lock *br_lck = NULL;
 394                 bool err;
 395
 396                 lock_pid = get_lock_pid( data, blr->lock_num, large_file_format);
 397                 count = get_lock_count( data, blr->lock_num, large_file_format);
 398                 offset = get_lock_offset( data, blr->lock_num, large_file_format, &err);
 399
 400                 /*
 401                  * We know err cannot be set as if it was the lock
 402                  * request would never have been queued. JRA.
 403                  */
 404                 errno = 0;
 405                 br_lck = do_lock(smbd_messaging_context(),
 406                                 fsp,
 407                                 lock_pid,
 408                                 count,
 409                                 offset,
 410                                 ((locktype & LOCKING_ANDX_SHARED_LOCK) ?
 411                                         READ_LOCK : WRITE_LOCK),
 412                                 WINDOWS_LOCK,
 413                                 True,
 414                                 &status,
 415                                 &blr->blocking_pid);
 416
 417                 TALLOC_FREE(br_lck);
 418
 419                 if (NT_STATUS_IS_ERR(status)) {
 420                         break;
 421                 }
 422         }
 423
 424         if(blr->lock_num == num_locks) {
 425                 /*
 426                  * Success - we got all the locks.
 427                  */
 428
 429                 DEBUG(3,("process_lockingX file = %s, fnum=%d type=%d num_locks=%d\n",
 430                          fsp->fsp_name, fsp->fnum, (unsigned int)locktype, num_locks) );
 431
 432                 reply_lockingX_success(blr);
 433                 return True;
 434         }
 435
 436         if (!NT_STATUS_EQUAL(status,NT_STATUS_LOCK_NOT_GRANTED) &&
 437             !NT_STATUS_EQUAL(status,NT_STATUS_FILE_LOCK_CONFLICT)) {
 438                 /*
 439                  * We have other than a "can't get lock"
 440                  * error. Free any locks we had and return an error.
 441                  * Return True so we get dequeued.
 442                  */
 443                 blocking_lock_reply_error(blr, status);
 444                 return True;
 445         }
 446
 447         /*
 448          * Still can't get all the locks - keep waiting.
 449          */
 450
 451         DEBUG(10,("process_lockingX: only got %d locks of %d needed for file %s, fnum = %d. \
 452 Waiting....\n",
 453                   blr->lock_num, num_locks, fsp->fsp_name, fsp->fnum));
 454
 455         return False;
 456 }
 457
 458 /****************************************************************************
 459  Attempt to get the posix lock request from a SMBtrans2 call.
 460  Returns True if we want to be removed from the list.
 461 *****************************************************************************/
 462
 463 static bool process_trans2(blocking_lock_record *blr)
 464 {
 465         char params[2];
 466         NTSTATUS status;
 467         struct byte_range_lock *br_lck = do_lock(smbd_messaging_context(),
 468                                                 blr->fsp,
 469                                                 blr->lock_pid,
 470                                                 blr->count,
 471                                                 blr->offset,
 472                                                 blr->lock_type,
 473                                                 blr->lock_flav,
 474                                                 True,
 475                                                 &status,
 476                                                 &blr->blocking_pid);
 477         TALLOC_FREE(br_lck);
 478
 479         if (!NT_STATUS_IS_OK(status)) {
 480                 if (ERROR_WAS_LOCK_DENIED(status)) {
 481                         /* Still can't get the lock, just keep waiting. */
 482                         return False;
 483                 }
 484                 /*
 485                  * We have other than a "can't get lock"
 486                  * error. Send an error and return True so we get dequeued.
 487                  */
 488                 blocking_lock_reply_error(blr, status);
 489                 return True;
 490         }
 491
 492         /* We finally got the lock, return success. */
 493
 494         SSVAL(params,0,0);
 495         /* Fake up max_data_bytes here - we know it fits. */
 496         send_trans2_replies(blr->fsp->conn, blr->req, params, 2, NULL, 0, 0xffff);
 497         return True;
 498 }
 499
 500
 501 /****************************************************************************
 502  Process a blocking lock SMB.
 503  Returns True if we want to be removed from the list.
 504 *****************************************************************************/
 505
 506 static bool blocking_lock_record_process(blocking_lock_record *blr)
 507 {
 508         switch(blr->req->cmd) {
 509                 case SMBlockingX:
 510                         return process_lockingX(blr);
 511                 case SMBtrans2:
 512                 case SMBtranss2:
 513                         return process_trans2(blr);
 514                 default:
 515                         DEBUG(0,("blocking_lock_record_process: PANIC - unknown type on blocking lock queue - exiting.!\n"));
 516                         exit_server("PANIC - unknown type on blocking lock queue");
 517         }
 518         return False; /* Keep compiler happy. */
 519 }
 520
 521 /****************************************************************************
 522  Cancel entries by fnum from the blocking lock pending queue.
 523 *****************************************************************************/
 524
 525 void cancel_pending_lock_requests_by_fid(files_struct *fsp, struct byte_range_lock *br_lck)
 526 {
 527         blocking_lock_record *blr, *next = NULL;
 528
 529         for(blr = blocking_lock_queue; blr; blr = next) {
 530                 unsigned char locktype = 0;
 531
 532                 next = blr->next;
 533                 if (blr->fsp->fnum != fsp->fnum) {
 534                         continue;
 535                 }
 536
 537                 if (blr->req->cmd == SMBlockingX) {
 538                         locktype = CVAL(blr->req->vwv+3, 0);
 539                 }
 540
 541                 DEBUG(10, ("remove_pending_lock_requests_by_fid - removing "
 542                            "request type %d for file %s fnum = %d\n",
 543                            blr->req->cmd, fsp->fsp_name, fsp->fnum));
 544
 545                 brl_lock_cancel(br_lck,
 546                                 blr->lock_pid,
 547                                 procid_self(),
 548                                 blr->offset,
 549                                 blr->count,
 550                                 blr->lock_flav);
 551
 552                 blocking_lock_cancel(fsp,
 553                                      blr->lock_pid,
 554                                      blr->offset,
 555                                      blr->count,
 556                                      blr->lock_flav,
 557                                      locktype,
 558                                      NT_STATUS_RANGE_NOT_LOCKED);
 559
 560                 /* We're closing the file fsp here, so ensure
 561                  * we don't have a dangling pointer. */
 562                 blr->fsp = NULL;
 563         }
 564 }
 565
 566 /****************************************************************************
 567  Delete entries by mid from the blocking lock pending queue. Always send reply.
 568 *****************************************************************************/
 569
 570 void remove_pending_lock_requests_by_mid(int mid)
 571 {
 572         blocking_lock_record *blr, *next = NULL;
 573
 574         for(blr = blocking_lock_queue; blr; blr = next) {
 575                 files_struct *fsp;
 576                 struct byte_range_lock *br_lck;
 577
 578                 next = blr->next;
 579
 580                 if (blr->req->mid != mid) {
 581                         continue;
 582                 }
 583
 584                 fsp = blr->fsp;
 585                 br_lck = brl_get_locks(talloc_tos(), fsp);
 586
 587                 if (br_lck) {
 588                         DEBUG(10, ("remove_pending_lock_requests_by_mid - "
 589                                    "removing request type %d for file %s fnum "
 590                                    "= %d\n", blr->req->cmd, fsp->fsp_name,
 591                                    fsp->fnum ));
 592
 593                         brl_lock_cancel(br_lck,
 594                                         blr->lock_pid,
 595                                         procid_self(),
 596                                         blr->offset,
 597                                         blr->count,
 598                                         blr->lock_flav);
 599                         TALLOC_FREE(br_lck);
 600                 }
 601
 602                 blocking_lock_reply_error(blr,NT_STATUS_FILE_LOCK_CONFLICT);
 603                 DLIST_REMOVE(blocking_lock_queue, blr);
 604                 TALLOC_FREE(blr);
 605         }
 606 }
 607
 608 /****************************************************************************
 609  Is this mid a blocking lock request on the queue ?
 610 *****************************************************************************/
 611
 612 bool blocking_lock_was_deferred(int mid)
 613 {
 614         blocking_lock_record *blr, *next = NULL;
 615
 616         for(blr = blocking_lock_queue; blr; blr = next) {
 617                 next = blr->next;
 618                 if(blr->req->mid == mid) {
 619                         return True;
 620                 }
 621         }
 622         return False;
 623 }
 624
 625 /****************************************************************************
 626   Set a flag as an unlock request affects one of our pending locks.
 627 *****************************************************************************/
 628
 629 static void received_unlock_msg(struct messaging_context *msg,
 630                                 void *private_data,
 631                                 uint32_t msg_type,
 632                                 struct server_id server_id,
 633                                 DATA_BLOB *data)
 634 {
 635         DEBUG(10,("received_unlock_msg\n"));
 636         process_blocking_lock_queue();
 637 }
 638
 639 /****************************************************************************
 640  Process the blocking lock queue. Note that this is only called as root.
 641 *****************************************************************************/
 642
 643 static void process_blocking_lock_queue(void)
 644 {
 645         struct timeval tv_curr = timeval_current();
 646         blocking_lock_record *blr, *next = NULL;
 647         bool recalc_timeout = False;
 648
 649         /*
 650          * Go through the queue and see if we can get any of the locks.
 651          */
 652
 653         for (blr = blocking_lock_queue; blr; blr = next) {
 654
 655                 next = blr->next;
 656
 657                 /*
 658                  * Go through the remaining locks and try and obtain them.
 659                  * The call returns True if all locks were obtained successfully
 660                  * and False if we still need to wait.
 661                  */
 662
 663                 if(blocking_lock_record_process(blr)) {
 664                         struct byte_range_lock *br_lck = brl_get_locks(
 665                                 talloc_tos(), blr->fsp);
 666
 667                         if (br_lck) {
 668                                 brl_lock_cancel(br_lck,
 669                                         blr->lock_pid,
 670                                         procid_self(),
 671                                         blr->offset,
 672                                         blr->count,
 673                                         blr->lock_flav);
 674                                 TALLOC_FREE(br_lck);
 675                         }
 676
 677                         DLIST_REMOVE(blocking_lock_queue, blr);
 678                         TALLOC_FREE(blr);
 679                         recalc_timeout = True;
 680                         continue;
 681                 }
 682
 683                 /*
 684                  * We couldn't get the locks for this record on the list.
 685                  * If the time has expired, return a lock error.
 686                  */
 687
 688                 if (!timeval_is_zero(&blr->expire_time) && timeval_compare(&blr->expire_time, &tv_curr) <= 0) {
 689                         struct byte_range_lock *br_lck = brl_get_locks(
 690                                 talloc_tos(), blr->fsp);
 691
 692                         /*
 693                          * Lock expired - throw away all previously
 694                          * obtained locks and return lock error.
 695                          */
 696
 697                         if (br_lck) {
 698                                 DEBUG(5,("process_blocking_lock_queue: "
 699                                          "pending lock fnum = %d for file %s "
 700                                          "timed out.\n", blr->fsp->fnum,
 701                                          blr->fsp->fsp_name ));
 702
 703                                 brl_lock_cancel(br_lck,
 704                                         blr->lock_pid,
 705                                         procid_self(),
 706                                         blr->offset,
 707                                         blr->count,
 708                                         blr->lock_flav);
 709                                 TALLOC_FREE(br_lck);
 710                         }
 711
 712                         blocking_lock_reply_error(blr,NT_STATUS_FILE_LOCK_CONFLICT);
 713                         DLIST_REMOVE(blocking_lock_queue, blr);
 714                         TALLOC_FREE(blr);
 715                         recalc_timeout = True;
 716                 }
 717         }
 718
 719         if (recalc_timeout) {
 720                 recalc_brl_timeout();
 721         }
 722 }
 723
 724 /****************************************************************************
 725  Handle a cancel message. Lock already moved onto the cancel queue.
 726 *****************************************************************************/
 727
 728 #define MSG_BLOCKING_LOCK_CANCEL_SIZE (sizeof(blocking_lock_record *) + sizeof(NTSTATUS))
 729
 730 static void process_blocking_lock_cancel_message(struct messaging_context *ctx,
 731                                                  void *private_data,
 732                                                  uint32_t msg_type,
 733                                                  struct server_id server_id,
 734                                                  DATA_BLOB *data)
 735 {
 736         NTSTATUS err;
 737         const char *msg = (const char *)data->data;
 738         blocking_lock_record *blr;
 739
 740         if (data->data == NULL) {
 741                 smb_panic("process_blocking_lock_cancel_message: null msg");
 742         }
 743
 744         if (data->length != MSG_BLOCKING_LOCK_CANCEL_SIZE) {
 745                 DEBUG(0, ("process_blocking_lock_cancel_message: "
 746                           "Got invalid msg len %d\n", (int)data->length));
 747                 smb_panic("process_blocking_lock_cancel_message: bad msg");
 748         }
 749
 750         memcpy(&blr, msg, sizeof(blr));
 751         memcpy(&err, &msg[sizeof(blr)], sizeof(NTSTATUS));
 752
 753         DEBUG(10,("process_blocking_lock_cancel_message: returning error %s\n",
 754                 nt_errstr(err) ));
 755
 756         blocking_lock_reply_error(blr, err);
 757         DLIST_REMOVE(blocking_lock_cancelled_queue, blr);
 758         TALLOC_FREE(blr);
 759 }
 760
 761 /****************************************************************************
 762  Send ourselves a blocking lock cancelled message. Handled asynchronously above.
 763 *****************************************************************************/
 764
 765 bool blocking_lock_cancel(files_struct *fsp,
 766                         uint32 lock_pid,
 767                         uint64_t offset,
 768                         uint64_t count,
 769                         enum brl_flavour lock_flav,
 770                         unsigned char locktype,
 771                         NTSTATUS err)
 772 {
 773         char msg[MSG_BLOCKING_LOCK_CANCEL_SIZE];
 774         blocking_lock_record *blr;
 775
 776         if (!blocking_lock_cancel_state) {
 777                 /* Register our message. */
 778                 messaging_register(smbd_messaging_context(), NULL,
 779                                    MSG_SMB_BLOCKING_LOCK_CANCEL,
 780                                    process_blocking_lock_cancel_message);
 781
 782                 blocking_lock_cancel_state = True;
 783         }
 784
 785         for (blr = blocking_lock_queue; blr; blr = blr->next) {
 786                 if (fsp == blr->fsp &&
 787                                 lock_pid == blr->lock_pid &&
 788                                 offset == blr->offset &&
 789                                 count == blr->count &&
 790                                 lock_flav == blr->lock_flav) {
 791                         break;
 792                 }
 793         }
 794
 795         if (!blr) {
 796                 return False;
 797         }
 798
 799         /* Check the flags are right. */
 800         if (blr->req->cmd == SMBlockingX &&
 801                 (locktype & LOCKING_ANDX_LARGE_FILES) !=
 802                         (CVAL(blr->req->vwv+3, 0) & LOCKING_ANDX_LARGE_FILES)) {
 803                 return False;
 804         }
 805
 806         /* Move to cancelled queue. */
 807         DLIST_REMOVE(blocking_lock_queue, blr);
 808         DLIST_ADD(blocking_lock_cancelled_queue, blr);
 809
 810         /* Create the message. */
 811         memcpy(msg, &blr, sizeof(blr));
 812         memcpy(&msg[sizeof(blr)], &err, sizeof(NTSTATUS));
 813
 814         messaging_send_buf(smbd_messaging_context(), procid_self(),
 815                            MSG_SMB_BLOCKING_LOCK_CANCEL,
 816                            (uint8 *)&msg, sizeof(msg));
 817
 818         return True;
 819 }