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
 242         if (!srv_send_smb(smbd_server_fd(), (char *)blr->req->outbuf,
 243                         IS_CONN_ENCRYPTED(blr->fsp->conn))) {
 244                 exit_server_cleanly("send_blocking_reply: srv_send_smb failed.");
 245         }
 246
 247         TALLOC_FREE(blr->req->outbuf);
 248 }
 249
 250 /****************************************************************************
 251  Return a generic lock fail error blocking call.
 252 *****************************************************************************/
 253
 254 static void generic_blocking_lock_error(blocking_lock_record *blr, NTSTATUS status)
 255 {
 256         /* whenever a timeout is given w2k maps LOCK_NOT_GRANTED to
 257            FILE_LOCK_CONFLICT! (tridge) */
 258         if (NT_STATUS_EQUAL(status, NT_STATUS_LOCK_NOT_GRANTED)) {
 259                 status = NT_STATUS_FILE_LOCK_CONFLICT;
 260         }
 261
 262         if (NT_STATUS_EQUAL(status, NT_STATUS_FILE_LOCK_CONFLICT)) {
 263                 /* Store the last lock error. */
 264                 files_struct *fsp = blr->fsp;
 265
 266                 if (fsp) {
 267                         fsp->last_lock_failure.context.smbpid = blr->lock_pid;
 268                         fsp->last_lock_failure.context.tid = fsp->conn->cnum;
 269                         fsp->last_lock_failure.context.pid = procid_self();
 270                         fsp->last_lock_failure.start = blr->offset;
 271                         fsp->last_lock_failure.size = blr->count;
 272                         fsp->last_lock_failure.fnum = fsp->fnum;
 273                         fsp->last_lock_failure.lock_type = READ_LOCK; /* Don't care. */
 274                         fsp->last_lock_failure.lock_flav = blr->lock_flav;
 275                 }
 276         }
 277
 278         reply_nterror(blr->req, status);
 279         if (!srv_send_smb(smbd_server_fd(), (char *)blr->req->outbuf,
 280                           blr->req->encrypted)) {
 281                 exit_server_cleanly("generic_blocking_lock_error: srv_send_smb failed.");
 282         }
 283         TALLOC_FREE(blr->req->outbuf);
 284 }
 285
 286 /****************************************************************************
 287  Return a lock fail error for a lockingX call. Undo all the locks we have
 288  obtained first.
 289 *****************************************************************************/
 290
 291 static void reply_lockingX_error(blocking_lock_record *blr, NTSTATUS status)
 292 {
 293         files_struct *fsp = blr->fsp;
 294         uint16 num_ulocks = SVAL(blr->req->vwv+6, 0);
 295         uint64_t count = (uint64_t)0, offset = (uint64_t) 0;
 296         uint32 lock_pid;
 297         unsigned char locktype = CVAL(blr->req->vwv+3, 0);
 298         bool large_file_format = (locktype & LOCKING_ANDX_LARGE_FILES);
 299         uint8_t *data;
 300         int i;
 301
 302         data = (uint8_t *)blr->req->buf
 303                 + ((large_file_format ? 20 : 10)*num_ulocks);
 304
 305         /*
 306          * Data now points at the beginning of the list
 307          * of smb_lkrng structs.
 308          */
 309
 310         /*
 311          * Ensure we don't do a remove on the lock that just failed,
 312          * as under POSIX rules, if we have a lock already there, we
 313          * will delete it (and we shouldn't) .....
 314          */
 315
 316         for(i = blr->lock_num - 1; i >= 0; i--) {
 317                 bool err;
 318
 319                 lock_pid = get_lock_pid( data, i, large_file_format);
 320                 count = get_lock_count( data, i, large_file_format);
 321                 offset = get_lock_offset( data, i, large_file_format, &err);
 322
 323                 /*
 324                  * We know err cannot be set as if it was the lock
 325                  * request would never have been queued. JRA.
 326                  */
 327
 328                 do_unlock(smbd_messaging_context(),
 329                         fsp,
 330                         lock_pid,
 331                         count,
 332                         offset,
 333                         WINDOWS_LOCK);
 334         }
 335
 336         generic_blocking_lock_error(blr, status);
 337 }
 338
 339 /****************************************************************************
 340  Return a lock fail error.
 341 *****************************************************************************/
 342
 343 static void blocking_lock_reply_error(blocking_lock_record *blr, NTSTATUS status)
 344 {
 345         switch(blr->req->cmd) {
 346         case SMBlockingX:
 347                 reply_lockingX_error(blr, status);
 348                 break;
 349         case SMBtrans2:
 350         case SMBtranss2:
 351                 reply_nterror(blr->req, status);
 352
 353                 /*
 354                  * construct_reply_common has done us the favor to pre-fill
 355                  * the command field with SMBtranss2 which is wrong :-)
 356                  */
 357                 SCVAL(blr->req->outbuf,smb_com,SMBtrans2);
 358
 359                 if (!srv_send_smb(smbd_server_fd(),
 360                                   (char *)blr->req->outbuf,
 361                                   IS_CONN_ENCRYPTED(blr->fsp->conn))) {
 362                         exit_server_cleanly("blocking_lock_reply_error: "
 363                                             "srv_send_smb failed.");
 364                 }
 365                 TALLOC_FREE(blr->req->outbuf);
 366                 break;
 367         default:
 368                 DEBUG(0,("blocking_lock_reply_error: PANIC - unknown type on blocking lock queue - exiting.!\n"));
 369                 exit_server("PANIC - unknown type on blocking lock queue");
 370         }
 371 }
 372
 373 /****************************************************************************
 374  Attempt to finish off getting all pending blocking locks for a lockingX call.
 375  Returns True if we want to be removed from the list.
 376 *****************************************************************************/
 377
 378 static bool process_lockingX(blocking_lock_record *blr)
 379 {
 380         unsigned char locktype = CVAL(blr->req->vwv+3, 0);
 381         files_struct *fsp = blr->fsp;
 382         uint16 num_ulocks = SVAL(blr->req->vwv+6, 0);
 383         uint16 num_locks = SVAL(blr->req->vwv+7, 0);
 384         uint64_t count = (uint64_t)0, offset = (uint64_t)0;
 385         uint32 lock_pid;
 386         bool large_file_format = (locktype & LOCKING_ANDX_LARGE_FILES);
 387         uint8_t *data;
 388         NTSTATUS status = NT_STATUS_OK;
 389
 390         data = (uint8_t *)blr->req->buf
 391                 + ((large_file_format ? 20 : 10)*num_ulocks);
 392
 393         /*
 394          * Data now points at the beginning of the list
 395          * of smb_lkrng structs.
 396          */
 397
 398         for(; blr->lock_num < num_locks; blr->lock_num++) {
 399                 struct byte_range_lock *br_lck = NULL;
 400                 bool err;
 401
 402                 lock_pid = get_lock_pid( data, blr->lock_num, large_file_format);
 403                 count = get_lock_count( data, blr->lock_num, large_file_format);
 404                 offset = get_lock_offset( data, blr->lock_num, large_file_format, &err);
 405
 406                 /*
 407                  * We know err cannot be set as if it was the lock
 408                  * request would never have been queued. JRA.
 409                  */
 410                 errno = 0;
 411                 br_lck = do_lock(smbd_messaging_context(),
 412                                 fsp,
 413                                 lock_pid,
 414                                 count,
 415                                 offset,
 416                                 ((locktype & LOCKING_ANDX_SHARED_LOCK) ?
 417                                         READ_LOCK : WRITE_LOCK),
 418                                 WINDOWS_LOCK,
 419                                 True,
 420                                 &status,
 421                                 &blr->blocking_pid);
 422
 423                 TALLOC_FREE(br_lck);
 424
 425                 if (NT_STATUS_IS_ERR(status)) {
 426                         break;
 427                 }
 428         }
 429
 430         if(blr->lock_num == num_locks) {
 431                 /*
 432                  * Success - we got all the locks.
 433                  */
 434
 435                 DEBUG(3,("process_lockingX file = %s, fnum=%d type=%d num_locks=%d\n",
 436                          fsp->fsp_name, fsp->fnum, (unsigned int)locktype, num_locks) );
 437
 438                 reply_lockingX_success(blr);
 439                 return True;
 440         }
 441
 442         if (!NT_STATUS_EQUAL(status,NT_STATUS_LOCK_NOT_GRANTED) &&
 443             !NT_STATUS_EQUAL(status,NT_STATUS_FILE_LOCK_CONFLICT)) {
 444                 /*
 445                  * We have other than a "can't get lock"
 446                  * error. Free any locks we had and return an error.
 447                  * Return True so we get dequeued.
 448                  */
 449                 blocking_lock_reply_error(blr, status);
 450                 return True;
 451         }
 452
 453         /*
 454          * Still can't get all the locks - keep waiting.
 455          */
 456
 457         DEBUG(10,("process_lockingX: only got %d locks of %d needed for file %s, fnum = %d. \
 458 Waiting....\n",
 459                   blr->lock_num, num_locks, fsp->fsp_name, fsp->fnum));
 460
 461         return False;
 462 }
 463
 464 /****************************************************************************
 465  Attempt to get the posix lock request from a SMBtrans2 call.
 466  Returns True if we want to be removed from the list.
 467 *****************************************************************************/
 468
 469 static bool process_trans2(blocking_lock_record *blr)
 470 {
 471         char params[2];
 472         NTSTATUS status;
 473         struct byte_range_lock *br_lck = do_lock(smbd_messaging_context(),
 474                                                 blr->fsp,
 475                                                 blr->lock_pid,
 476                                                 blr->count,
 477                                                 blr->offset,
 478                                                 blr->lock_type,
 479                                                 blr->lock_flav,
 480                                                 True,
 481                                                 &status,
 482                                                 &blr->blocking_pid);
 483         TALLOC_FREE(br_lck);
 484
 485         if (!NT_STATUS_IS_OK(status)) {
 486                 if (ERROR_WAS_LOCK_DENIED(status)) {
 487                         /* Still can't get the lock, just keep waiting. */
 488                         return False;
 489                 }
 490                 /*
 491                  * We have other than a "can't get lock"
 492                  * error. Send an error and return True so we get dequeued.
 493                  */
 494                 blocking_lock_reply_error(blr, status);
 495                 return True;
 496         }
 497
 498         /* We finally got the lock, return success. */
 499
 500         SSVAL(params,0,0);
 501         /* Fake up max_data_bytes here - we know it fits. */
 502         send_trans2_replies(blr->fsp->conn, blr->req, params, 2, NULL, 0, 0xffff);
 503         return True;
 504 }
 505
 506
 507 /****************************************************************************
 508  Process a blocking lock SMB.
 509  Returns True if we want to be removed from the list.
 510 *****************************************************************************/
 511
 512 static bool blocking_lock_record_process(blocking_lock_record *blr)
 513 {
 514         switch(blr->req->cmd) {
 515                 case SMBlockingX:
 516                         return process_lockingX(blr);
 517                 case SMBtrans2:
 518                 case SMBtranss2:
 519                         return process_trans2(blr);
 520                 default:
 521                         DEBUG(0,("blocking_lock_record_process: PANIC - unknown type on blocking lock queue - exiting.!\n"));
 522                         exit_server("PANIC - unknown type on blocking lock queue");
 523         }
 524         return False; /* Keep compiler happy. */
 525 }
 526
 527 /****************************************************************************
 528  Cancel entries by fnum from the blocking lock pending queue.
 529 *****************************************************************************/
 530
 531 void cancel_pending_lock_requests_by_fid(files_struct *fsp, struct byte_range_lock *br_lck)
 532 {
 533         blocking_lock_record *blr, *next = NULL;
 534
 535         for(blr = blocking_lock_queue; blr; blr = next) {
 536                 unsigned char locktype = 0;
 537
 538                 next = blr->next;
 539                 if (blr->fsp->fnum != fsp->fnum) {
 540                         continue;
 541                 }
 542
 543                 if (blr->req->cmd == SMBlockingX) {
 544                         locktype = CVAL(blr->req->vwv+3, 0);
 545                 }
 546
 547                 DEBUG(10, ("remove_pending_lock_requests_by_fid - removing "
 548                            "request type %d for file %s fnum = %d\n",
 549                            blr->req->cmd, fsp->fsp_name, fsp->fnum));
 550
 551                 brl_lock_cancel(br_lck,
 552                                 blr->lock_pid,
 553                                 procid_self(),
 554                                 blr->offset,
 555                                 blr->count,
 556                                 blr->lock_flav);
 557
 558                 blocking_lock_cancel(fsp,
 559                                      blr->lock_pid,
 560                                      blr->offset,
 561                                      blr->count,
 562                                      blr->lock_flav,
 563                                      locktype,
 564                                      NT_STATUS_RANGE_NOT_LOCKED);
 565
 566                 /* We're closing the file fsp here, so ensure
 567                  * we don't have a dangling pointer. */
 568                 blr->fsp = NULL;
 569         }
 570 }
 571
 572 /****************************************************************************
 573  Delete entries by mid from the blocking lock pending queue. Always send reply.
 574 *****************************************************************************/
 575
 576 void remove_pending_lock_requests_by_mid(int mid)
 577 {
 578         blocking_lock_record *blr, *next = NULL;
 579
 580         for(blr = blocking_lock_queue; blr; blr = next) {
 581                 files_struct *fsp;
 582                 struct byte_range_lock *br_lck;
 583
 584                 next = blr->next;
 585
 586                 if (blr->req->mid != mid) {
 587                         continue;
 588                 }
 589
 590                 fsp = blr->fsp;
 591                 br_lck = brl_get_locks(talloc_tos(), fsp);
 592
 593                 if (br_lck) {
 594                         DEBUG(10, ("remove_pending_lock_requests_by_mid - "
 595                                    "removing request type %d for file %s fnum "
 596                                    "= %d\n", blr->req->cmd, fsp->fsp_name,
 597                                    fsp->fnum ));
 598
 599                         brl_lock_cancel(br_lck,
 600                                         blr->lock_pid,
 601                                         procid_self(),
 602                                         blr->offset,
 603                                         blr->count,
 604                                         blr->lock_flav);
 605                         TALLOC_FREE(br_lck);
 606                 }
 607
 608                 blocking_lock_reply_error(blr,NT_STATUS_FILE_LOCK_CONFLICT);
 609                 DLIST_REMOVE(blocking_lock_queue, blr);
 610                 TALLOC_FREE(blr);
 611         }
 612 }
 613
 614 /****************************************************************************
 615  Is this mid a blocking lock request on the queue ?
 616 *****************************************************************************/
 617
 618 bool blocking_lock_was_deferred(int mid)
 619 {
 620         blocking_lock_record *blr, *next = NULL;
 621
 622         for(blr = blocking_lock_queue; blr; blr = next) {
 623                 next = blr->next;
 624                 if(blr->req->mid == mid) {
 625                         return True;
 626                 }
 627         }
 628         return False;
 629 }
 630
 631 /****************************************************************************
 632   Set a flag as an unlock request affects one of our pending locks.
 633 *****************************************************************************/
 634
 635 static void received_unlock_msg(struct messaging_context *msg,
 636                                 void *private_data,
 637                                 uint32_t msg_type,
 638                                 struct server_id server_id,
 639                                 DATA_BLOB *data)
 640 {
 641         DEBUG(10,("received_unlock_msg\n"));
 642         process_blocking_lock_queue();
 643 }
 644
 645 /****************************************************************************
 646  Process the blocking lock queue. Note that this is only called as root.
 647 *****************************************************************************/
 648
 649 static void process_blocking_lock_queue(void)
 650 {
 651         struct timeval tv_curr = timeval_current();
 652         blocking_lock_record *blr, *next = NULL;
 653         bool recalc_timeout = False;
 654
 655         /*
 656          * Go through the queue and see if we can get any of the locks.
 657          */
 658
 659         for (blr = blocking_lock_queue; blr; blr = next) {
 660
 661                 next = blr->next;
 662
 663                 /*
 664                  * Go through the remaining locks and try and obtain them.
 665                  * The call returns True if all locks were obtained successfully
 666                  * and False if we still need to wait.
 667                  */
 668
 669                 if(blocking_lock_record_process(blr)) {
 670                         struct byte_range_lock *br_lck = brl_get_locks(
 671                                 talloc_tos(), blr->fsp);
 672
 673                         if (br_lck) {
 674                                 brl_lock_cancel(br_lck,
 675                                         blr->lock_pid,
 676                                         procid_self(),
 677                                         blr->offset,
 678                                         blr->count,
 679                                         blr->lock_flav);
 680                                 TALLOC_FREE(br_lck);
 681                         }
 682
 683                         DLIST_REMOVE(blocking_lock_queue, blr);
 684                         TALLOC_FREE(blr);
 685                         recalc_timeout = True;
 686                         continue;
 687                 }
 688
 689                 /*
 690                  * We couldn't get the locks for this record on the list.
 691                  * If the time has expired, return a lock error.
 692                  */
 693
 694                 if (!timeval_is_zero(&blr->expire_time) && timeval_compare(&blr->expire_time, &tv_curr) <= 0) {
 695                         struct byte_range_lock *br_lck = brl_get_locks(
 696                                 talloc_tos(), blr->fsp);
 697
 698                         /*
 699                          * Lock expired - throw away all previously
 700                          * obtained locks and return lock error.
 701                          */
 702
 703                         if (br_lck) {
 704                                 DEBUG(5,("process_blocking_lock_queue: "
 705                                          "pending lock fnum = %d for file %s "
 706                                          "timed out.\n", blr->fsp->fnum,
 707                                          blr->fsp->fsp_name ));
 708
 709                                 brl_lock_cancel(br_lck,
 710                                         blr->lock_pid,
 711                                         procid_self(),
 712                                         blr->offset,
 713                                         blr->count,
 714                                         blr->lock_flav);
 715                                 TALLOC_FREE(br_lck);
 716                         }
 717
 718                         blocking_lock_reply_error(blr,NT_STATUS_FILE_LOCK_CONFLICT);
 719                         DLIST_REMOVE(blocking_lock_queue, blr);
 720                         TALLOC_FREE(blr);
 721                         recalc_timeout = True;
 722                 }
 723         }
 724
 725         if (recalc_timeout) {
 726                 recalc_brl_timeout();
 727         }
 728 }
 729
 730 /****************************************************************************
 731  Handle a cancel message. Lock already moved onto the cancel queue.
 732 *****************************************************************************/
 733
 734 #define MSG_BLOCKING_LOCK_CANCEL_SIZE (sizeof(blocking_lock_record *) + sizeof(NTSTATUS))
 735
 736 static void process_blocking_lock_cancel_message(struct messaging_context *ctx,
 737                                                  void *private_data,
 738                                                  uint32_t msg_type,
 739                                                  struct server_id server_id,
 740                                                  DATA_BLOB *data)
 741 {
 742         NTSTATUS err;
 743         const char *msg = (const char *)data->data;
 744         blocking_lock_record *blr;
 745
 746         if (data->data == NULL) {
 747                 smb_panic("process_blocking_lock_cancel_message: null msg");
 748         }
 749
 750         if (data->length != MSG_BLOCKING_LOCK_CANCEL_SIZE) {
 751                 DEBUG(0, ("process_blocking_lock_cancel_message: "
 752                           "Got invalid msg len %d\n", (int)data->length));
 753                 smb_panic("process_blocking_lock_cancel_message: bad msg");
 754         }
 755
 756         memcpy(&blr, msg, sizeof(blr));
 757         memcpy(&err, &msg[sizeof(blr)], sizeof(NTSTATUS));
 758
 759         DEBUG(10,("process_blocking_lock_cancel_message: returning error %s\n",
 760                 nt_errstr(err) ));
 761
 762         blocking_lock_reply_error(blr, err);
 763         DLIST_REMOVE(blocking_lock_cancelled_queue, blr);
 764         TALLOC_FREE(blr);
 765 }
 766
 767 /****************************************************************************
 768  Send ourselves a blocking lock cancelled message. Handled asynchronously above.
 769 *****************************************************************************/
 770
 771 bool blocking_lock_cancel(files_struct *fsp,
 772                         uint32 lock_pid,
 773                         uint64_t offset,
 774                         uint64_t count,
 775                         enum brl_flavour lock_flav,
 776                         unsigned char locktype,
 777                         NTSTATUS err)
 778 {
 779         char msg[MSG_BLOCKING_LOCK_CANCEL_SIZE];
 780         blocking_lock_record *blr;
 781
 782         if (!blocking_lock_cancel_state) {
 783                 /* Register our message. */
 784                 messaging_register(smbd_messaging_context(), NULL,
 785                                    MSG_SMB_BLOCKING_LOCK_CANCEL,
 786                                    process_blocking_lock_cancel_message);
 787
 788                 blocking_lock_cancel_state = True;
 789         }
 790
 791         for (blr = blocking_lock_queue; blr; blr = blr->next) {
 792                 if (fsp == blr->fsp &&
 793                                 lock_pid == blr->lock_pid &&
 794                                 offset == blr->offset &&
 795                                 count == blr->count &&
 796                                 lock_flav == blr->lock_flav) {
 797                         break;
 798                 }
 799         }
 800
 801         if (!blr) {
 802                 return False;
 803         }
 804
 805         /* Check the flags are right. */
 806         if (blr->req->cmd == SMBlockingX &&
 807                 (locktype & LOCKING_ANDX_LARGE_FILES) !=
 808                         (CVAL(blr->req->vwv+3, 0) & LOCKING_ANDX_LARGE_FILES)) {
 809                 return False;
 810         }
 811
 812         /* Move to cancelled queue. */
 813         DLIST_REMOVE(blocking_lock_queue, blr);
 814         DLIST_ADD(blocking_lock_cancelled_queue, blr);
 815
 816         /* Create the message. */
 817         memcpy(msg, &blr, sizeof(blr));
 818         memcpy(&msg[sizeof(blr)], &err, sizeof(NTSTATUS));
 819
 820         messaging_send_buf(smbd_messaging_context(), procid_self(),
 821                            MSG_SMB_BLOCKING_LOCK_CANCEL,
 822                            (uint8 *)&msg, sizeof(msg));
 823
 824         return True;
 825 }