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 2 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, write to the Free Software
  18    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19 */
  20
  21 #include "includes.h"
  22 #undef DBGC_CLASS
  23 #define DBGC_CLASS DBGC_LOCKING
  24
  25 extern int max_send;
  26
  27 /****************************************************************************
  28  This is the structure to queue to implement blocking locks.
  29  notify. It consists of the requesting SMB and the expiry time.
  30 *****************************************************************************/
  31
  32 typedef struct _blocking_lock_record {
  33         struct _blocking_lock_record *next;
  34         struct _blocking_lock_record *prev;
  35         int com_type;
  36         files_struct *fsp;
  37         struct timeval expire_time;
  38         int lock_num;
  39         SMB_BIG_UINT offset;
  40         SMB_BIG_UINT count;
  41         uint32 lock_pid;
  42         enum brl_flavour lock_flav;
  43         enum brl_type lock_type;
  44         char *inbuf;
  45         int length;
  46 } blocking_lock_record;
  47
  48 /* dlink list we store pending lock records on. */
  49 static blocking_lock_record *blocking_lock_queue;
  50
  51 /* dlink list we move cancelled lock records onto. */
  52 static blocking_lock_record *blocking_lock_cancelled_queue;
  53
  54 /****************************************************************************
  55  Destructor for the above structure.
  56 ****************************************************************************/
  57
  58 static void free_blocking_lock_record(blocking_lock_record *blr)
  59 {
  60         SAFE_FREE(blr->inbuf);
  61         SAFE_FREE(blr);
  62 }
  63
  64 /****************************************************************************
  65  Determine if this is a secondary element of a chained SMB.
  66   **************************************************************************/
  67
  68 static BOOL in_chained_smb(void)
  69 {
  70         return (chain_size != 0);
  71 }
  72
  73 static void received_unlock_msg(int msg_type, struct process_id src,
  74                                 void *buf, size_t len);
  75
  76 /****************************************************************************
  77  Function to push a blocking lock request onto the lock queue.
  78 ****************************************************************************/
  79
  80 BOOL push_blocking_lock_request( struct byte_range_lock *br_lck,
  81                 char *inbuf, int length,
  82                 files_struct *fsp,
  83                 int lock_timeout,
  84                 int lock_num,
  85                 uint32 lock_pid,
  86                 enum brl_type lock_type,
  87                 enum brl_flavour lock_flav,
  88                 SMB_BIG_UINT offset, SMB_BIG_UINT count)
  89 {
  90         static BOOL set_lock_msg;
  91         blocking_lock_record *blr;
  92         NTSTATUS status;
  93
  94         if(in_chained_smb() ) {
  95                 DEBUG(0,("push_blocking_lock_request: cannot queue a chained request (currently).\n"));
  96                 return False;
  97         }
  98
  99         /*
 100          * Now queue an entry on the blocking lock queue. We setup
 101          * the expiration time here.
 102          */
 103
 104         if((blr = SMB_MALLOC_P(blocking_lock_record)) == NULL) {
 105                 DEBUG(0,("push_blocking_lock_request: Malloc fail !\n" ));
 106                 return False;
 107         }
 108
 109         blr->next = NULL;
 110         blr->prev = NULL;
 111
 112         if((blr->inbuf = (char *)SMB_MALLOC(length)) == NULL) {
 113                 DEBUG(0,("push_blocking_lock_request: Malloc fail (2)!\n" ));
 114                 SAFE_FREE(blr);
 115                 return False;
 116         }
 117
 118         blr->com_type = CVAL(inbuf,smb_com);
 119         blr->fsp = fsp;
 120         if (lock_timeout == -1) {
 121                 blr->expire_time.tv_sec = 0;
 122                 blr->expire_time.tv_usec = 0; /* Never expire. */
 123         } else {
 124                 blr->expire_time = timeval_current_ofs(lock_timeout/1000,
 125                                         (lock_timeout % 1000) * 1000);
 126         }
 127         blr->lock_num = lock_num;
 128         blr->lock_pid = lock_pid;
 129         blr->lock_flav = lock_flav;
 130         blr->lock_type = lock_type;
 131         blr->offset = offset;
 132         blr->count = count;
 133         memcpy(blr->inbuf, inbuf, length);
 134         blr->length = length;
 135
 136         /* Add a pending lock record for this. */
 137         status = brl_lock(br_lck,
 138                         lock_pid,
 139                         procid_self(),
 140                         offset,
 141                         count,
 142                         lock_type == READ_LOCK ? PENDING_READ_LOCK : PENDING_WRITE_LOCK,
 143                         blr->lock_flav,
 144                         lock_timeout ? True : False); /* blocking_lock. */
 145
 146         if (!NT_STATUS_IS_OK(status)) {
 147                 DEBUG(0,("push_blocking_lock_request: failed to add PENDING_LOCK record.\n"));
 148                 DLIST_REMOVE(blocking_lock_queue, blr);
 149                 free_blocking_lock_record(blr);
 150                 return False;
 151         }
 152
 153         DLIST_ADD_END(blocking_lock_queue, blr, blocking_lock_record *);
 154
 155         /* Ensure we'll receive messages when this is unlocked. */
 156         if (!set_lock_msg) {
 157                 message_register(MSG_SMB_UNLOCK, received_unlock_msg);
 158                 set_lock_msg = True;
 159         }
 160
 161         DEBUG(3,("push_blocking_lock_request: lock request length=%d blocked with "
 162                 "expiry time (%u sec. %u usec) (+%d msec) for fnum = %d, name = %s\n",
 163                 length, (unsigned int)blr->expire_time.tv_sec,
 164                 (unsigned int)blr->expire_time.tv_usec, lock_timeout,
 165                 blr->fsp->fnum, blr->fsp->fsp_name ));
 166
 167         /* Push the MID of this packet on the signing queue. */
 168         srv_defer_sign_response(SVAL(inbuf,smb_mid));
 169
 170         return True;
 171 }
 172
 173 /****************************************************************************
 174  Return a smd with a given size.
 175 *****************************************************************************/
 176
 177 static void send_blocking_reply(char *outbuf, int outsize)
 178 {
 179         if(outsize > 4)
 180                 smb_setlen(outbuf,outsize - 4);
 181
 182         if (!send_smb(smbd_server_fd(),outbuf))
 183                 exit_server_cleanly("send_blocking_reply: send_smb failed.");
 184 }
 185
 186 /****************************************************************************
 187  Return a lockingX success SMB.
 188 *****************************************************************************/
 189
 190 static void reply_lockingX_success(blocking_lock_record *blr)
 191 {
 192         char *outbuf = get_OutBuffer();
 193         int bufsize = BUFFER_SIZE;
 194         char *inbuf = blr->inbuf;
 195         int outsize = 0;
 196
 197         construct_reply_common(inbuf, outbuf);
 198         set_message(outbuf,2,0,True);
 199
 200         /*
 201          * As this message is a lockingX call we must handle
 202          * any following chained message correctly.
 203          * This is normally handled in construct_reply(),
 204          * but as that calls switch_message, we can't use
 205          * that here and must set up the chain info manually.
 206          */
 207
 208         outsize = chain_reply(inbuf,outbuf,blr->length,bufsize);
 209
 210         outsize += chain_size;
 211
 212         send_blocking_reply(outbuf,outsize);
 213 }
 214
 215 /****************************************************************************
 216  Return a generic lock fail error blocking call.
 217 *****************************************************************************/
 218
 219 static void generic_blocking_lock_error(blocking_lock_record *blr, NTSTATUS status)
 220 {
 221         char *outbuf = get_OutBuffer();
 222         char *inbuf = blr->inbuf;
 223         construct_reply_common(inbuf, outbuf);
 224
 225         /* whenever a timeout is given w2k maps LOCK_NOT_GRANTED to
 226            FILE_LOCK_CONFLICT! (tridge) */
 227         if (NT_STATUS_EQUAL(status, NT_STATUS_LOCK_NOT_GRANTED)) {
 228                 status = NT_STATUS_FILE_LOCK_CONFLICT;
 229         }
 230
 231         if (NT_STATUS_EQUAL(status, NT_STATUS_FILE_LOCK_CONFLICT)) {
 232                 /* Store the last lock error. */
 233                 files_struct *fsp = blr->fsp;
 234
 235                 fsp->last_lock_failure.context.smbpid = blr->lock_pid;
 236                 fsp->last_lock_failure.context.tid = fsp->conn->cnum;
 237                 fsp->last_lock_failure.context.pid = procid_self();
 238                 fsp->last_lock_failure.start = blr->offset;
 239                 fsp->last_lock_failure.size = blr->count;
 240                 fsp->last_lock_failure.fnum = fsp->fnum;
 241                 fsp->last_lock_failure.lock_type = READ_LOCK; /* Don't care. */
 242                 fsp->last_lock_failure.lock_flav = blr->lock_flav;
 243         }
 244
 245         ERROR_NT(status);
 246         if (!send_smb(smbd_server_fd(),outbuf)) {
 247                 exit_server_cleanly("generic_blocking_lock_error: send_smb failed.");
 248         }
 249 }
 250
 251 /****************************************************************************
 252  Return a lock fail error for a lockingX call. Undo all the locks we have
 253  obtained first.
 254 *****************************************************************************/
 255
 256 static void reply_lockingX_error(blocking_lock_record *blr, NTSTATUS status)
 257 {
 258         char *inbuf = blr->inbuf;
 259         files_struct *fsp = blr->fsp;
 260         uint16 num_ulocks = SVAL(inbuf,smb_vwv6);
 261         SMB_BIG_UINT count = (SMB_BIG_UINT)0, offset = (SMB_BIG_UINT) 0;
 262         uint32 lock_pid;
 263         unsigned char locktype = CVAL(inbuf,smb_vwv3);
 264         BOOL large_file_format = (locktype & LOCKING_ANDX_LARGE_FILES);
 265         char *data;
 266         int i;
 267
 268         data = smb_buf(inbuf) + ((large_file_format ? 20 : 10)*num_ulocks);
 269
 270         /*
 271          * Data now points at the beginning of the list
 272          * of smb_lkrng structs.
 273          */
 274
 275         /*
 276          * Ensure we don't do a remove on the lock that just failed,
 277          * as under POSIX rules, if we have a lock already there, we
 278          * will delete it (and we shouldn't) .....
 279          */
 280
 281         for(i = blr->lock_num - 1; i >= 0; i--) {
 282                 BOOL err;
 283
 284                 lock_pid = get_lock_pid( data, i, large_file_format);
 285                 count = get_lock_count( data, i, large_file_format);
 286                 offset = get_lock_offset( data, i, large_file_format, &err);
 287
 288                 /*
 289                  * We know err cannot be set as if it was the lock
 290                  * request would never have been queued. JRA.
 291                  */
 292
 293                 do_unlock(fsp,
 294                         lock_pid,
 295                         count,
 296                         offset,
 297                         WINDOWS_LOCK);
 298         }
 299
 300         generic_blocking_lock_error(blr, status);
 301 }
 302
 303 /****************************************************************************
 304  Return a lock fail error.
 305 *****************************************************************************/
 306
 307 static void blocking_lock_reply_error(blocking_lock_record *blr, NTSTATUS status)
 308 {
 309         switch(blr->com_type) {
 310         case SMBlockingX:
 311                 reply_lockingX_error(blr, status);
 312                 break;
 313         case SMBtrans2:
 314         case SMBtranss2:
 315                 {
 316                         char *outbuf = get_OutBuffer();
 317                         char *inbuf = blr->inbuf;
 318                         construct_reply_common(inbuf, outbuf);
 319                         /* construct_reply_common has done us the favor to pre-fill the
 320                          * command field with SMBtranss2 which is wrong :-)
 321                          */
 322                         SCVAL(outbuf,smb_com,SMBtrans2);
 323                         ERROR_NT(status);
 324                         if (!send_smb(smbd_server_fd(),outbuf)) {
 325                                 exit_server_cleanly("blocking_lock_reply_error: send_smb failed.");
 326                         }
 327                         break;
 328                 }
 329         default:
 330                 DEBUG(0,("blocking_lock_reply_error: PANIC - unknown type on blocking lock queue - exiting.!\n"));
 331                 exit_server("PANIC - unknown type on blocking lock queue");
 332         }
 333 }
 334
 335 /****************************************************************************
 336  Attempt to finish off getting all pending blocking locks for a lockingX call.
 337  Returns True if we want to be removed from the list.
 338 *****************************************************************************/
 339
 340 static BOOL process_lockingX(blocking_lock_record *blr)
 341 {
 342         char *inbuf = blr->inbuf;
 343         unsigned char locktype = CVAL(inbuf,smb_vwv3);
 344         files_struct *fsp = blr->fsp;
 345         uint16 num_ulocks = SVAL(inbuf,smb_vwv6);
 346         uint16 num_locks = SVAL(inbuf,smb_vwv7);
 347         SMB_BIG_UINT count = (SMB_BIG_UINT)0, offset = (SMB_BIG_UINT)0;
 348         uint32 lock_pid;
 349         BOOL large_file_format = (locktype & LOCKING_ANDX_LARGE_FILES);
 350         char *data;
 351         NTSTATUS status = NT_STATUS_OK;
 352
 353         data = smb_buf(inbuf) + ((large_file_format ? 20 : 10)*num_ulocks);
 354
 355         /*
 356          * Data now points at the beginning of the list
 357          * of smb_lkrng structs.
 358          */
 359
 360         for(; blr->lock_num < num_locks; blr->lock_num++) {
 361                 struct byte_range_lock *br_lck = NULL;
 362                 BOOL err;
 363
 364                 lock_pid = get_lock_pid( data, blr->lock_num, large_file_format);
 365                 count = get_lock_count( data, blr->lock_num, large_file_format);
 366                 offset = get_lock_offset( data, blr->lock_num, large_file_format, &err);
 367
 368                 /*
 369                  * We know err cannot be set as if it was the lock
 370                  * request would never have been queued. JRA.
 371                  */
 372                 errno = 0;
 373                 br_lck = do_lock(fsp,
 374                                 lock_pid,
 375                                 count,
 376                                 offset,
 377                                 ((locktype & LOCKING_ANDX_SHARED_LOCK) ?
 378                                         READ_LOCK : WRITE_LOCK),
 379                                 WINDOWS_LOCK,
 380                                 True,
 381                                 &status);
 382
 383                 TALLOC_FREE(br_lck);
 384
 385                 if (NT_STATUS_IS_ERR(status)) {
 386                         break;
 387                 }
 388         }
 389
 390         if(blr->lock_num == num_locks) {
 391                 /*
 392                  * Success - we got all the locks.
 393                  */
 394
 395                 DEBUG(3,("process_lockingX file = %s, fnum=%d type=%d num_locks=%d\n",
 396                          fsp->fsp_name, fsp->fnum, (unsigned int)locktype, num_locks) );
 397
 398                 reply_lockingX_success(blr);
 399                 return True;
 400         } else if (!NT_STATUS_EQUAL(status,NT_STATUS_LOCK_NOT_GRANTED) &&
 401                         !NT_STATUS_EQUAL(status,NT_STATUS_FILE_LOCK_CONFLICT)) {
 402                         /*
 403                          * We have other than a "can't get lock"
 404                          * error. Free any locks we had and return an error.
 405                          * Return True so we get dequeued.
 406                          */
 407
 408                 blocking_lock_reply_error(blr, status);
 409                 return True;
 410         }
 411
 412         /*
 413          * Still can't get all the locks - keep waiting.
 414          */
 415
 416         DEBUG(10,("process_lockingX: only got %d locks of %d needed for file %s, fnum = %d. \
 417 Waiting....\n",
 418                   blr->lock_num, num_locks, fsp->fsp_name, fsp->fnum));
 419
 420         return False;
 421 }
 422
 423 /****************************************************************************
 424  Attempt to get the posix lock request from a SMBtrans2 call.
 425  Returns True if we want to be removed from the list.
 426 *****************************************************************************/
 427
 428 static BOOL process_trans2(blocking_lock_record *blr)
 429 {
 430         char *inbuf = blr->inbuf;
 431         char *outbuf;
 432         char params[2];
 433         NTSTATUS status;
 434         struct byte_range_lock *br_lck = do_lock(blr->fsp,
 435                                                 blr->lock_pid,
 436                                                 blr->count,
 437                                                 blr->offset,
 438                                                 blr->lock_type,
 439                                                 blr->lock_flav,
 440                                                 True,
 441                                                 &status);
 442         TALLOC_FREE(br_lck);
 443
 444         if (!NT_STATUS_IS_OK(status)) {
 445                 if (ERROR_WAS_LOCK_DENIED(status)) {
 446                         /* Still can't get the lock, just keep waiting. */
 447                         return False;
 448                 }
 449                 /*
 450                  * We have other than a "can't get lock"
 451                  * error. Send an error and return True so we get dequeued.
 452                  */
 453                 blocking_lock_reply_error(blr, status);
 454                 return True;
 455         }
 456
 457         /* We finally got the lock, return success. */
 458         outbuf = get_OutBuffer();
 459         construct_reply_common(inbuf, outbuf);
 460         SCVAL(outbuf,smb_com,SMBtrans2);
 461         SSVAL(params,0,0);
 462         /* Fake up max_data_bytes here - we know it fits. */
 463         send_trans2_replies(outbuf, max_send, params, 2, NULL, 0, 0xffff);
 464         return True;
 465 }
 466
 467
 468 /****************************************************************************
 469  Process a blocking lock SMB.
 470  Returns True if we want to be removed from the list.
 471 *****************************************************************************/
 472
 473 static BOOL blocking_lock_record_process(blocking_lock_record *blr)
 474 {
 475         switch(blr->com_type) {
 476                 case SMBlockingX:
 477                         return process_lockingX(blr);
 478                 case SMBtrans2:
 479                 case SMBtranss2:
 480                         return process_trans2(blr);
 481                 default:
 482                         DEBUG(0,("blocking_lock_record_process: PANIC - unknown type on blocking lock queue - exiting.!\n"));
 483                         exit_server("PANIC - unknown type on blocking lock queue");
 484         }
 485         return False; /* Keep compiler happy. */
 486 }
 487
 488 /****************************************************************************
 489  Cancel entries by fnum from the blocking lock pending queue.
 490 *****************************************************************************/
 491
 492 void cancel_pending_lock_requests_by_fid(files_struct *fsp, struct byte_range_lock *br_lck)
 493 {
 494         blocking_lock_record *blr, *next = NULL;
 495
 496         for(blr = blocking_lock_queue; blr; blr = next) {
 497                 next = blr->next;
 498                 if(blr->fsp->fnum == fsp->fnum) {
 499                         unsigned char locktype = 0;
 500
 501                         if (blr->com_type == SMBlockingX) {
 502                                 locktype = CVAL(blr->inbuf,smb_vwv3);
 503                         }
 504
 505                         if (br_lck) {
 506                                 DEBUG(10,("remove_pending_lock_requests_by_fid - removing request type %d for \
 507 file %s fnum = %d\n", blr->com_type, fsp->fsp_name, fsp->fnum ));
 508
 509                                 brl_lock_cancel(br_lck,
 510                                         blr->lock_pid,
 511                                         procid_self(),
 512                                         blr->offset,
 513                                         blr->count,
 514                                         blr->lock_flav);
 515
 516                                 blocking_lock_cancel(fsp,
 517                                         blr->lock_pid,
 518                                         blr->offset,
 519                                         blr->count,
 520                                         blr->lock_flav,
 521                                         locktype,
 522                                         NT_STATUS_RANGE_NOT_LOCKED);
 523                         }
 524                 }
 525         }
 526 }
 527
 528 /****************************************************************************
 529  Delete entries by mid from the blocking lock pending queue. Always send reply.
 530 *****************************************************************************/
 531
 532 void remove_pending_lock_requests_by_mid(int mid)
 533 {
 534         blocking_lock_record *blr, *next = NULL;
 535
 536         for(blr = blocking_lock_queue; blr; blr = next) {
 537                 next = blr->next;
 538                 if(SVAL(blr->inbuf,smb_mid) == mid) {
 539                         files_struct *fsp = blr->fsp;
 540                         struct byte_range_lock *br_lck = brl_get_locks(NULL, fsp);
 541
 542                         if (br_lck) {
 543                                 DEBUG(10,("remove_pending_lock_requests_by_mid - removing request type %d for \
 544 file %s fnum = %d\n", blr->com_type, fsp->fsp_name, fsp->fnum ));
 545
 546                                 brl_lock_cancel(br_lck,
 547                                         blr->lock_pid,
 548                                         procid_self(),
 549                                         blr->offset,
 550                                         blr->count,
 551                                         blr->lock_flav);
 552                                 TALLOC_FREE(br_lck);
 553                         }
 554
 555                         blocking_lock_reply_error(blr,NT_STATUS_FILE_LOCK_CONFLICT);
 556                         DLIST_REMOVE(blocking_lock_queue, blr);
 557                         free_blocking_lock_record(blr);
 558                 }
 559         }
 560 }
 561
 562 /****************************************************************************
 563   Set a flag as an unlock request affects one of our pending locks.
 564 *****************************************************************************/
 565
 566 static void received_unlock_msg(int msg_type, struct process_id src,
 567                                 void *buf, size_t len)
 568 {
 569         DEBUG(10,("received_unlock_msg\n"));
 570         process_blocking_lock_queue();
 571 }
 572
 573 /****************************************************************************
 574  Return the number of milliseconds to the next blocking locks timeout, or default_timeout
 575 *****************************************************************************/
 576
 577 unsigned int blocking_locks_timeout_ms(unsigned int default_timeout_ms)
 578 {
 579         unsigned int timeout_ms = default_timeout_ms;
 580         struct timeval tv_curr;
 581         SMB_BIG_INT min_tv_dif_us = 0x7FFFFFFF; /* A large +ve number. */
 582         blocking_lock_record *blr = blocking_lock_queue;
 583
 584         /* note that we avoid the GetTimeOfDay() syscall if there are no blocking locks */
 585         if (!blr) {
 586                 return timeout_ms;
 587         }
 588
 589         tv_curr = timeval_current();
 590
 591         for (; blr; blr = blr->next) {
 592                 SMB_BIG_INT tv_dif_us;
 593
 594                 if (timeval_is_zero(&blr->expire_time)) {
 595                         continue; /* Never timeout. */
 596                 }
 597
 598                 tv_dif_us = usec_time_diff(&blr->expire_time, &tv_curr);
 599                 min_tv_dif_us = MIN(min_tv_dif_us, tv_dif_us);
 600         }
 601
 602         if (min_tv_dif_us < 0) {
 603                 min_tv_dif_us = 0;
 604         }
 605
 606         timeout_ms = (unsigned int)(min_tv_dif_us / (SMB_BIG_INT)1000);
 607
 608         if (timeout_ms < 1) {
 609                 timeout_ms = 1;
 610         }
 611
 612         DEBUG(10,("blocking_locks_timeout_ms: returning %u\n", timeout_ms));
 613
 614         return timeout_ms;
 615 }
 616
 617 /****************************************************************************
 618  Process the blocking lock queue. Note that this is only called as root.
 619 *****************************************************************************/
 620
 621 void process_blocking_lock_queue(void)
 622 {
 623         struct timeval tv_curr = timeval_current();
 624         blocking_lock_record *blr, *next = NULL;
 625
 626         /*
 627          * Go through the queue and see if we can get any of the locks.
 628          */
 629
 630         for (blr = blocking_lock_queue; blr; blr = next) {
 631                 connection_struct *conn = NULL;
 632                 uint16 vuid;
 633                 files_struct *fsp = NULL;
 634
 635                 next = blr->next;
 636
 637                 /*
 638                  * Ensure we don't have any old chain_fsp values
 639                  * sitting around....
 640                  */
 641                 chain_size = 0;
 642                 file_chain_reset();
 643                 fsp = blr->fsp;
 644
 645                 conn = conn_find(SVAL(blr->inbuf,smb_tid));
 646                 vuid = (lp_security() == SEC_SHARE) ? UID_FIELD_INVALID :
 647                                 SVAL(blr->inbuf,smb_uid);
 648
 649                 DEBUG(5,("process_blocking_lock_queue: examining pending lock fnum = %d for file %s\n",
 650                         fsp->fnum, fsp->fsp_name ));
 651
 652                 if (!timeval_is_zero(&blr->expire_time) && timeval_compare(&blr->expire_time, &tv_curr) <= 0) {
 653                         struct byte_range_lock *br_lck = brl_get_locks(NULL, fsp);
 654
 655                         /*
 656                          * Lock expired - throw away all previously
 657                          * obtained locks and return lock error.
 658                          */
 659
 660                         if (br_lck) {
 661                                 DEBUG(5,("process_blocking_lock_queue: pending lock fnum = %d for file %s timed out.\n",
 662                                         fsp->fnum, fsp->fsp_name ));
 663
 664                                 brl_lock_cancel(br_lck,
 665                                         blr->lock_pid,
 666                                         procid_self(),
 667                                         blr->offset,
 668                                         blr->count,
 669                                         blr->lock_flav);
 670                                 TALLOC_FREE(br_lck);
 671                         }
 672
 673                         blocking_lock_reply_error(blr,NT_STATUS_FILE_LOCK_CONFLICT);
 674                         DLIST_REMOVE(blocking_lock_queue, blr);
 675                         free_blocking_lock_record(blr);
 676                         continue;
 677                 }
 678
 679                 if(!change_to_user(conn,vuid)) {
 680                         struct byte_range_lock *br_lck = brl_get_locks(NULL, fsp);
 681
 682                         /*
 683                          * Remove the entry and return an error to the client.
 684                          */
 685
 686                         if (br_lck) {
 687                                 brl_lock_cancel(br_lck,
 688                                         blr->lock_pid,
 689                                         procid_self(),
 690                                         blr->offset,
 691                                         blr->count,
 692                                         blr->lock_flav);
 693                                 TALLOC_FREE(br_lck);
 694                         }
 695
 696                         DEBUG(0,("process_blocking_lock_queue: Unable to become user vuid=%d.\n",
 697                                 vuid ));
 698                         blocking_lock_reply_error(blr,NT_STATUS_ACCESS_DENIED);
 699                         DLIST_REMOVE(blocking_lock_queue, blr);
 700                         free_blocking_lock_record(blr);
 701                         continue;
 702                 }
 703
 704                 if(!set_current_service(conn,SVAL(blr->inbuf,smb_flg),True)) {
 705                         struct byte_range_lock *br_lck = brl_get_locks(NULL, fsp);
 706
 707                         /*
 708                          * Remove the entry and return an error to the client.
 709                          */
 710
 711                         if (br_lck) {
 712                                 brl_lock_cancel(br_lck,
 713                                         blr->lock_pid,
 714                                         procid_self(),
 715                                         blr->offset,
 716                                         blr->count,
 717                                         blr->lock_flav);
 718                                 TALLOC_FREE(br_lck);
 719                         }
 720
 721                         DEBUG(0,("process_blocking_lock_queue: Unable to become service Error was %s.\n", strerror(errno) ));
 722                         blocking_lock_reply_error(blr,NT_STATUS_ACCESS_DENIED);
 723                         DLIST_REMOVE(blocking_lock_queue, blr);
 724                         free_blocking_lock_record(blr);
 725                         change_to_root_user();
 726                         continue;
 727                 }
 728
 729                 /*
 730                  * Go through the remaining locks and try and obtain them.
 731                  * The call returns True if all locks were obtained successfully
 732                  * and False if we still need to wait.
 733                  */
 734
 735                 if(blocking_lock_record_process(blr)) {
 736                         struct byte_range_lock *br_lck = brl_get_locks(NULL, fsp);
 737
 738                         if (br_lck) {
 739                                 brl_lock_cancel(br_lck,
 740                                         blr->lock_pid,
 741                                         procid_self(),
 742                                         blr->offset,
 743                                         blr->count,
 744                                         blr->lock_flav);
 745                                 TALLOC_FREE(br_lck);
 746                         }
 747
 748                         DLIST_REMOVE(blocking_lock_queue, blr);
 749                         free_blocking_lock_record(blr);
 750                 }
 751                 change_to_root_user();
 752         }
 753 }
 754
 755 /****************************************************************************
 756  Handle a cancel message. Lock already moved onto the cancel queue.
 757 *****************************************************************************/
 758
 759 #define MSG_BLOCKING_LOCK_CANCEL_SIZE (sizeof(blocking_lock_record *) + sizeof(NTSTATUS))
 760
 761 static void process_blocking_lock_cancel_message(int msg_type, struct process_id src,
 762                                          void *buf, size_t len)
 763 {
 764         NTSTATUS err;
 765         const char *msg = (const char *)buf;
 766         blocking_lock_record *blr;
 767
 768         if (buf == NULL) {
 769                 smb_panic("process_blocking_lock_cancel_message: null msg\n");
 770         }
 771
 772         if (len != MSG_BLOCKING_LOCK_CANCEL_SIZE) {
 773                 DEBUG(0, ("process_blocking_lock_cancel_message: "
 774                         "Got invalid msg len %d\n", (int)len));
 775                 smb_panic("process_blocking_lock_cancel_message: bad msg\n");
 776         }
 777
 778         memcpy(&blr, msg, sizeof(blr));
 779         memcpy(&err, &msg[sizeof(blr)], sizeof(NTSTATUS));
 780
 781         DEBUG(10,("process_blocking_lock_cancel_message: returning error %s\n",
 782                 nt_errstr(err) ));
 783
 784         blocking_lock_reply_error(blr, err);
 785         DLIST_REMOVE(blocking_lock_cancelled_queue, blr);
 786         free_blocking_lock_record(blr);
 787 }
 788
 789 /****************************************************************************
 790  Send ourselves a blocking lock cancelled message. Handled asynchronously above.
 791 *****************************************************************************/
 792
 793 BOOL blocking_lock_cancel(files_struct *fsp,
 794                         uint32 lock_pid,
 795                         SMB_BIG_UINT offset,
 796                         SMB_BIG_UINT count,
 797                         enum brl_flavour lock_flav,
 798                         unsigned char locktype,
 799                         NTSTATUS err)
 800 {
 801         static BOOL initialized;
 802         char msg[MSG_BLOCKING_LOCK_CANCEL_SIZE];
 803         blocking_lock_record *blr;
 804
 805         if (!initialized) {
 806                 /* Register our message. */
 807                 message_register(MSG_SMB_BLOCKING_LOCK_CANCEL,
 808                                 process_blocking_lock_cancel_message);
 809
 810                 initialized = True;
 811         }
 812
 813         for (blr = blocking_lock_queue; blr; blr = blr->next) {
 814                 if (fsp == blr->fsp &&
 815                                 lock_pid == blr->lock_pid &&
 816                                 offset == blr->offset &&
 817                                 count == blr->count &&
 818                                 lock_flav == blr->lock_flav) {
 819                         break;
 820                 }
 821         }
 822
 823         if (!blr) {
 824                 return False;
 825         }
 826
 827         /* Check the flags are right. */
 828         if (blr->com_type == SMBlockingX &&
 829                 (locktype & LOCKING_ANDX_LARGE_FILES) !=
 830                         (CVAL(blr->inbuf,smb_vwv3) & LOCKING_ANDX_LARGE_FILES)) {
 831                 return False;
 832         }
 833
 834         /* Move to cancelled queue. */
 835         DLIST_REMOVE(blocking_lock_queue, blr);
 836         DLIST_ADD(blocking_lock_cancelled_queue, blr);
 837
 838         /* Create the message. */
 839         memcpy(msg, &blr, sizeof(blr));
 840         memcpy(&msg[sizeof(blr)], &err, sizeof(NTSTATUS));
 841
 842         message_send_pid(pid_to_procid(sys_getpid()),
 843                         MSG_SMB_BLOCKING_LOCK_CANCEL,
 844                         &msg, sizeof(msg), True);
 845
 846         return True;
 847 }