source/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
  23 extern char *OutBuffer;
  24
  25 /****************************************************************************
  26  This is the structure to queue to implement blocking locks.
  27  notify. It consists of the requesting SMB and the expiry time.
  28 *****************************************************************************/
  29
  30 typedef struct {
  31         ubi_slNode msg_next;
  32         int com_type;
  33         files_struct *fsp;
  34         time_t expire_time;
  35         int lock_num;
  36         SMB_BIG_UINT offset;
  37         SMB_BIG_UINT count;
  38         uint16 lock_pid;
  39         char *inbuf;
  40         int length;
  41 } blocking_lock_record;
  42
  43 static ubi_slList blocking_lock_queue = { NULL, (ubi_slNodePtr)&blocking_lock_queue, 0};
  44
  45 /****************************************************************************
  46  Destructor for the above structure.
  47 ****************************************************************************/
  48
  49 static void free_blocking_lock_record(blocking_lock_record *blr)
  50 {
  51         SAFE_FREE(blr->inbuf);
  52         SAFE_FREE(blr);
  53 }
  54
  55 /****************************************************************************
  56  Get the files_struct given a particular queued SMB.
  57 *****************************************************************************/
  58
  59 static files_struct *get_fsp_from_pkt(char *inbuf)
  60 {
  61         switch(CVAL(inbuf,smb_com)) {
  62                 case SMBlock:
  63                 case SMBlockread:
  64                         return file_fsp(inbuf,smb_vwv0);
  65                 case SMBlockingX:
  66                         return file_fsp(inbuf,smb_vwv2);
  67                 default:
  68                         DEBUG(0,("get_fsp_from_pkt: PANIC - unknown type on blocking lock queue - exiting.!\n"));
  69                         exit_server("PANIC - unknown type on blocking lock queue");
  70         }
  71         return NULL; /* Keep compiler happy. */
  72 }
  73
  74 /****************************************************************************
  75  Determine if this is a secondary element of a chained SMB.
  76   **************************************************************************/
  77
  78 static BOOL in_chained_smb(void)
  79 {
  80         return (chain_size != 0);
  81 }
  82
  83 static void received_unlock_msg(int msg_type, pid_t src, void *buf, size_t len);
  84
  85 /****************************************************************************
  86  Function to push a blocking lock request onto the lock queue.
  87 ****************************************************************************/
  88
  89 BOOL push_blocking_lock_request( char *inbuf, int length, int lock_timeout,
  90                 int lock_num, uint16 lock_pid, SMB_BIG_UINT offset, SMB_BIG_UINT count)
  91 {
  92         static BOOL set_lock_msg;
  93         blocking_lock_record *blr;
  94         NTSTATUS status;
  95
  96         if(in_chained_smb() ) {
  97                 DEBUG(0,("push_blocking_lock_request: cannot queue a chained request (currently).\n"));
  98                 return False;
  99         }
 100
 101         /*
 102          * Now queue an entry on the blocking lock queue. We setup
 103          * the expiration time here.
 104          */
 105
 106         if((blr = (blocking_lock_record *)malloc(sizeof(blocking_lock_record))) == NULL) {
 107                 DEBUG(0,("push_blocking_lock_request: Malloc fail !\n" ));
 108                 return False;
 109         }
 110
 111         if((blr->inbuf = (char *)malloc(length)) == NULL) {
 112                 DEBUG(0,("push_blocking_lock_request: Malloc fail (2)!\n" ));
 113                 SAFE_FREE(blr);
 114                 return False;
 115         }
 116
 117         blr->com_type = CVAL(inbuf,smb_com);
 118         blr->fsp = get_fsp_from_pkt(inbuf);
 119         blr->expire_time = (lock_timeout == -1) ? (time_t)-1 : time(NULL) + (time_t)lock_timeout;
 120         blr->lock_num = lock_num;
 121         blr->lock_pid = lock_pid;
 122         blr->offset = offset;
 123         blr->count = count;
 124         memcpy(blr->inbuf, inbuf, length);
 125         blr->length = length;
 126
 127         /* Add a pending lock record for this. */
 128         status = brl_lock(blr->fsp->dev, blr->fsp->inode, blr->fsp->fnum,
 129                         lock_pid, sys_getpid(), blr->fsp->conn->cnum,
 130                         offset, count, PENDING_LOCK);
 131
 132         if (!NT_STATUS_IS_OK(status)) {
 133                 DEBUG(0,("push_blocking_lock_request: failed to add PENDING_LOCK record.\n"));
 134                 free_blocking_lock_record(blr);
 135                 return False;
 136         }
 137
 138         ubi_slAddTail(&blocking_lock_queue, blr);
 139
 140         /* Ensure we'll receive messages when this is unlocked. */
 141         if (!set_lock_msg) {
 142                 message_register(MSG_SMB_UNLOCK, received_unlock_msg);
 143                 set_lock_msg = True;
 144         }
 145
 146         DEBUG(3,("push_blocking_lock_request: lock request length=%d blocked with expiry time %d (+%d) \
 147 for fnum = %d, name = %s\n", length, (int)blr->expire_time, lock_timeout,
 148                 blr->fsp->fnum, blr->fsp->fsp_name ));
 149
 150         /* Push the MID of this packet on the signing queue. */
 151         srv_defer_sign_response(SVAL(inbuf,smb_mid), True);
 152
 153         return True;
 154 }
 155
 156 /****************************************************************************
 157  Return a smd with a given size.
 158 *****************************************************************************/
 159
 160 static void send_blocking_reply(char *outbuf, int outsize)
 161 {
 162         if(outsize > 4)
 163                 smb_setlen(outbuf,outsize - 4);
 164
 165         if (!send_smb(smbd_server_fd(),outbuf))
 166                 exit_server("send_blocking_reply: send_smb failed.");
 167 }
 168
 169 /****************************************************************************
 170  Return a lockingX success SMB.
 171 *****************************************************************************/
 172
 173 static void reply_lockingX_success(blocking_lock_record *blr)
 174 {
 175         char *outbuf = OutBuffer;
 176         int bufsize = BUFFER_SIZE;
 177         char *inbuf = blr->inbuf;
 178         int outsize = 0;
 179
 180         construct_reply_common(inbuf, outbuf);
 181         set_message(outbuf,2,0,True);
 182
 183         /*
 184          * As this message is a lockingX call we must handle
 185          * any following chained message correctly.
 186          * This is normally handled in construct_reply(),
 187          * but as that calls switch_message, we can't use
 188          * that here and must set up the chain info manually.
 189          */
 190
 191         outsize = chain_reply(inbuf,outbuf,blr->length,bufsize);
 192
 193         outsize += chain_size;
 194
 195         send_blocking_reply(outbuf,outsize);
 196 }
 197
 198 /****************************************************************************
 199  Return a generic lock fail error blocking call.
 200 *****************************************************************************/
 201
 202 static void generic_blocking_lock_error(blocking_lock_record *blr, NTSTATUS status)
 203 {
 204         char *outbuf = OutBuffer;
 205         char *inbuf = blr->inbuf;
 206         construct_reply_common(inbuf, outbuf);
 207
 208         /* whenever a timeout is given w2k maps LOCK_NOT_GRANTED to
 209            FILE_LOCK_CONFLICT! (tridge) */
 210         if (NT_STATUS_EQUAL(status, NT_STATUS_LOCK_NOT_GRANTED)) {
 211                 status = NT_STATUS_FILE_LOCK_CONFLICT;
 212         }
 213
 214         ERROR_NT(status);
 215         if (!send_smb(smbd_server_fd(),outbuf))
 216                 exit_server("generic_blocking_lock_error: send_smb failed.");
 217 }
 218
 219 /****************************************************************************
 220  Return a lock fail error for a lockingX call. Undo all the locks we have
 221  obtained first.
 222 *****************************************************************************/
 223
 224 static void reply_lockingX_error(blocking_lock_record *blr, NTSTATUS status)
 225 {
 226         char *inbuf = blr->inbuf;
 227         files_struct *fsp = blr->fsp;
 228         connection_struct *conn = conn_find(SVAL(inbuf,smb_tid));
 229         uint16 num_ulocks = SVAL(inbuf,smb_vwv6);
 230         SMB_BIG_UINT count = (SMB_BIG_UINT)0, offset = (SMB_BIG_UINT) 0;
 231         uint16 lock_pid;
 232         unsigned char locktype = CVAL(inbuf,smb_vwv3);
 233         BOOL large_file_format = (locktype & LOCKING_ANDX_LARGE_FILES);
 234         char *data;
 235         int i;
 236
 237         data = smb_buf(inbuf) + ((large_file_format ? 20 : 10)*num_ulocks);
 238
 239         /*
 240          * Data now points at the beginning of the list
 241          * of smb_lkrng structs.
 242          */
 243
 244         /*
 245          * Ensure we don't do a remove on the lock that just failed,
 246          * as under POSIX rules, if we have a lock already there, we
 247          * will delete it (and we shouldn't) .....
 248          */
 249
 250         for(i = blr->lock_num - 1; i >= 0; i--) {
 251                 BOOL err;
 252
 253                 lock_pid = get_lock_pid( data, i, large_file_format);
 254                 count = get_lock_count( data, i, large_file_format);
 255                 offset = get_lock_offset( data, i, large_file_format, &err);
 256
 257                 /*
 258                  * We know err cannot be set as if it was the lock
 259                  * request would never have been queued. JRA.
 260                  */
 261
 262                 do_unlock(fsp,conn,lock_pid,count,offset);
 263         }
 264
 265         generic_blocking_lock_error(blr, status);
 266 }
 267
 268 /****************************************************************************
 269  Return a lock fail error.
 270 *****************************************************************************/
 271
 272 static void blocking_lock_reply_error(blocking_lock_record *blr, NTSTATUS status)
 273 {
 274         switch(blr->com_type) {
 275         case SMBlock:
 276         case SMBlockread:
 277                 generic_blocking_lock_error(blr, status);
 278                 break;
 279         case SMBlockingX:
 280                 reply_lockingX_error(blr, status);
 281                 break;
 282         default:
 283                 DEBUG(0,("blocking_lock_reply_error: PANIC - unknown type on blocking lock queue - exiting.!\n"));
 284                 exit_server("PANIC - unknown type on blocking lock queue");
 285         }
 286 }
 287
 288 /****************************************************************************
 289  Attempt to finish off getting all pending blocking locks for a lockread call.
 290  Returns True if we want to be removed from the list.
 291 *****************************************************************************/
 292
 293 static BOOL process_lockread(blocking_lock_record *blr)
 294 {
 295         char *outbuf = OutBuffer;
 296         char *inbuf = blr->inbuf;
 297         ssize_t nread = -1;
 298         char *data, *p;
 299         int outsize = 0;
 300         SMB_BIG_UINT startpos;
 301         size_t numtoread;
 302         NTSTATUS status;
 303         connection_struct *conn = conn_find(SVAL(inbuf,smb_tid));
 304         files_struct *fsp = blr->fsp;
 305
 306         numtoread = SVAL(inbuf,smb_vwv1);
 307         startpos = (SMB_BIG_UINT)IVAL(inbuf,smb_vwv2);
 308
 309         numtoread = MIN(BUFFER_SIZE-outsize,numtoread);
 310         data = smb_buf(outbuf) + 3;
 311
 312         status = do_lock_spin( fsp, conn, SVAL(inbuf,smb_pid), (SMB_BIG_UINT)numtoread,
 313                           startpos, READ_LOCK);
 314         if (NT_STATUS_V(status)) {
 315                 if (!NT_STATUS_EQUAL(status,NT_STATUS_LOCK_NOT_GRANTED) &&
 316                         !NT_STATUS_EQUAL(status,NT_STATUS_FILE_LOCK_CONFLICT)) {
 317                         /*
 318                          * We have other than a "can't get lock"
 319                          * error. Send an error.
 320                          * Return True so we get dequeued.
 321                          */
 322                         generic_blocking_lock_error(blr, status);
 323                         return True;
 324                 }
 325
 326                 /*
 327                  * Still waiting for lock....
 328                  */
 329
 330                 DEBUG(10,("process_lockread: failed to get lock for file = %s. Still waiting....\n",
 331                           fsp->fsp_name));
 332                 return False;
 333         }
 334
 335         nread = read_file(fsp,data,startpos,numtoread);
 336
 337         if (nread < 0) {
 338                 generic_blocking_lock_error(blr,NT_STATUS_ACCESS_DENIED);
 339                 return True;
 340         }
 341
 342         construct_reply_common(inbuf, outbuf);
 343         outsize = set_message(outbuf,5,0,True);
 344
 345         outsize += nread;
 346         SSVAL(outbuf,smb_vwv0,nread);
 347         SSVAL(outbuf,smb_vwv5,nread+3);
 348         p = smb_buf(outbuf);
 349         *p++ = 1;
 350         SSVAL(p,0,nread); p += 2;
 351         set_message_end(outbuf, p+nread);
 352
 353         DEBUG(3, ( "process_lockread file = %s, fnum=%d num=%d nread=%d\n",
 354                    fsp->fsp_name, fsp->fnum, (int)numtoread, (int)nread ) );
 355
 356         send_blocking_reply(outbuf,outsize);
 357         return True;
 358 }
 359
 360 /****************************************************************************
 361  Attempt to finish off getting all pending blocking locks for a lock call.
 362  Returns True if we want to be removed from the list.
 363 *****************************************************************************/
 364
 365 static BOOL process_lock(blocking_lock_record *blr)
 366 {
 367         char *outbuf = OutBuffer;
 368         char *inbuf = blr->inbuf;
 369         int outsize;
 370         SMB_BIG_UINT count = (SMB_BIG_UINT)0, offset = (SMB_BIG_UINT)0;
 371         NTSTATUS status;
 372         connection_struct *conn = conn_find(SVAL(inbuf,smb_tid));
 373         files_struct *fsp = blr->fsp;
 374
 375         count = IVAL_TO_SMB_OFF_T(inbuf,smb_vwv1);
 376         offset = IVAL_TO_SMB_OFF_T(inbuf,smb_vwv3);
 377
 378         errno = 0;
 379         status = do_lock_spin(fsp, conn, SVAL(inbuf,smb_pid), count,
 380                          offset, WRITE_LOCK);
 381         if (NT_STATUS_IS_ERR(status)) {
 382                 if (!NT_STATUS_EQUAL(status,NT_STATUS_LOCK_NOT_GRANTED) &&
 383                         !NT_STATUS_EQUAL(status,NT_STATUS_FILE_LOCK_CONFLICT)) {
 384                         /*
 385                          * We have other than a "can't get lock"
 386                          * error. Send an error.
 387                          * Return True so we get dequeued.
 388                          */
 389
 390                         blocking_lock_reply_error(blr, status);
 391                         return True;
 392                 }
 393                 /*
 394                  * Still can't get the lock - keep waiting.
 395                  */
 396                 DEBUG(10,("process_lock: failed to get lock for file = %s. Still waiting....\n",
 397                           fsp->fsp_name));
 398                 return False;
 399         }
 400
 401         /*
 402          * Success - we got the lock.
 403          */
 404
 405         DEBUG(3,("process_lock : file=%s fnum=%d offset=%.0f count=%.0f\n",
 406                  fsp->fsp_name, fsp->fnum, (double)offset, (double)count));
 407
 408         construct_reply_common(inbuf, outbuf);
 409         outsize = set_message(outbuf,0,0,True);
 410         send_blocking_reply(outbuf,outsize);
 411         return True;
 412 }
 413
 414 /****************************************************************************
 415  Attempt to finish off getting all pending blocking locks for a lockingX call.
 416  Returns True if we want to be removed from the list.
 417 *****************************************************************************/
 418
 419 static BOOL process_lockingX(blocking_lock_record *blr)
 420 {
 421         char *inbuf = blr->inbuf;
 422         unsigned char locktype = CVAL(inbuf,smb_vwv3);
 423         files_struct *fsp = blr->fsp;
 424         connection_struct *conn = conn_find(SVAL(inbuf,smb_tid));
 425         uint16 num_ulocks = SVAL(inbuf,smb_vwv6);
 426         uint16 num_locks = SVAL(inbuf,smb_vwv7);
 427         SMB_BIG_UINT count = (SMB_BIG_UINT)0, offset = (SMB_BIG_UINT)0;
 428         uint16 lock_pid;
 429         BOOL large_file_format = (locktype & LOCKING_ANDX_LARGE_FILES);
 430         char *data;
 431         NTSTATUS status = NT_STATUS_OK;
 432
 433         data = smb_buf(inbuf) + ((large_file_format ? 20 : 10)*num_ulocks);
 434
 435         /*
 436          * Data now points at the beginning of the list
 437          * of smb_lkrng structs.
 438          */
 439
 440         for(; blr->lock_num < num_locks; blr->lock_num++) {
 441                 BOOL err;
 442
 443                 lock_pid = get_lock_pid( data, blr->lock_num, large_file_format);
 444                 count = get_lock_count( data, blr->lock_num, large_file_format);
 445                 offset = get_lock_offset( data, blr->lock_num, large_file_format, &err);
 446
 447                 /*
 448                  * We know err cannot be set as if it was the lock
 449                  * request would never have been queued. JRA.
 450                  */
 451                 errno = 0;
 452                 status = do_lock_spin(fsp,conn,lock_pid,count,offset,
 453                                  ((locktype & 1) ? READ_LOCK : WRITE_LOCK));
 454                 if (NT_STATUS_IS_ERR(status)) break;
 455         }
 456
 457         if(blr->lock_num == num_locks) {
 458                 /*
 459                  * Success - we got all the locks.
 460                  */
 461
 462                 DEBUG(3,("process_lockingX file = %s, fnum=%d type=%d num_locks=%d\n",
 463                          fsp->fsp_name, fsp->fnum, (unsigned int)locktype, num_locks) );
 464
 465                 reply_lockingX_success(blr);
 466                 return True;
 467         } else if (!NT_STATUS_EQUAL(status,NT_STATUS_LOCK_NOT_GRANTED) &&
 468                         !NT_STATUS_EQUAL(status,NT_STATUS_FILE_LOCK_CONFLICT)) {
 469                         /*
 470                          * We have other than a "can't get lock"
 471                          * error. Free any locks we had and return an error.
 472                          * Return True so we get dequeued.
 473                          */
 474
 475                 blocking_lock_reply_error(blr, status);
 476                 return True;
 477         }
 478
 479         /*
 480          * Still can't get all the locks - keep waiting.
 481          */
 482
 483         DEBUG(10,("process_lockingX: only got %d locks of %d needed for file %s, fnum = %d. \
 484 Waiting....\n",
 485                   blr->lock_num, num_locks, fsp->fsp_name, fsp->fnum));
 486
 487         return False;
 488 }
 489
 490 /****************************************************************************
 491  Process a blocking lock SMB.
 492  Returns True if we want to be removed from the list.
 493 *****************************************************************************/
 494
 495 static BOOL blocking_lock_record_process(blocking_lock_record *blr)
 496 {
 497         switch(blr->com_type) {
 498                 case SMBlock:
 499                         return process_lock(blr);
 500                 case SMBlockread:
 501                         return process_lockread(blr);
 502                 case SMBlockingX:
 503                         return process_lockingX(blr);
 504                 default:
 505                         DEBUG(0,("blocking_lock_record_process: PANIC - unknown type on blocking lock queue - exiting.!\n"));
 506                         exit_server("PANIC - unknown type on blocking lock queue");
 507         }
 508         return False; /* Keep compiler happy. */
 509 }
 510
 511 /****************************************************************************
 512  Delete entries by fnum from the blocking lock pending queue.
 513 *****************************************************************************/
 514
 515 void remove_pending_lock_requests_by_fid(files_struct *fsp)
 516 {
 517         blocking_lock_record *blr = (blocking_lock_record *)ubi_slFirst( &blocking_lock_queue );
 518         blocking_lock_record *prev = NULL;
 519
 520         while(blr != NULL) {
 521                 if(blr->fsp->fnum == fsp->fnum) {
 522
 523                         DEBUG(10,("remove_pending_lock_requests_by_fid - removing request type %d for \
 524 file %s fnum = %d\n", blr->com_type, fsp->fsp_name, fsp->fnum ));
 525
 526                         brl_unlock(blr->fsp->dev, blr->fsp->inode, blr->fsp->fnum,
 527                                 blr->lock_pid, sys_getpid(), blr->fsp->conn->cnum,
 528                                 blr->offset, blr->count, True, NULL, NULL);
 529
 530                         free_blocking_lock_record((blocking_lock_record *)ubi_slRemNext( &blocking_lock_queue, prev));
 531                         blr = (blocking_lock_record *)(prev ? ubi_slNext(prev) : ubi_slFirst(&blocking_lock_queue));
 532                         continue;
 533                 }
 534
 535                 prev = blr;
 536                 blr = (blocking_lock_record *)ubi_slNext(blr);
 537         }
 538 }
 539
 540 /****************************************************************************
 541  Delete entries by mid from the blocking lock pending queue. Always send reply.
 542 *****************************************************************************/
 543
 544 void remove_pending_lock_requests_by_mid(int mid)
 545 {
 546         blocking_lock_record *blr = (blocking_lock_record *)ubi_slFirst( &blocking_lock_queue );
 547         blocking_lock_record *prev = NULL;
 548
 549         while(blr != NULL) {
 550                 if(SVAL(blr->inbuf,smb_mid) == mid) {
 551                         files_struct *fsp = blr->fsp;
 552
 553                         DEBUG(10,("remove_pending_lock_requests_by_mid - removing request type %d for \
 554 file %s fnum = %d\n", blr->com_type, fsp->fsp_name, fsp->fnum ));
 555
 556                         blocking_lock_reply_error(blr,NT_STATUS_CANCELLED);
 557                         brl_unlock(blr->fsp->dev, blr->fsp->inode, blr->fsp->fnum,
 558                                 blr->lock_pid, sys_getpid(), blr->fsp->conn->cnum,
 559                                 blr->offset, blr->count, True, NULL, NULL);
 560                         free_blocking_lock_record((blocking_lock_record *)ubi_slRemNext( &blocking_lock_queue, prev));
 561                         blr = (blocking_lock_record *)(prev ? ubi_slNext(prev) : ubi_slFirst(&blocking_lock_queue));
 562                         continue;
 563                 }
 564
 565                 prev = blr;
 566                 blr = (blocking_lock_record *)ubi_slNext(blr);
 567         }
 568 }
 569
 570 /****************************************************************************
 571   Set a flag as an unlock request affects one of our pending locks.
 572 *****************************************************************************/
 573
 574 static void received_unlock_msg(int msg_type, pid_t src, void *buf, size_t len)
 575 {
 576         DEBUG(10,("received_unlock_msg\n"));
 577         process_blocking_lock_queue(time(NULL));
 578 }
 579
 580 /****************************************************************************
 581  Return the number of seconds to the next blocking locks timeout, or default_timeout
 582 *****************************************************************************/
 583
 584 unsigned blocking_locks_timeout(unsigned default_timeout)
 585 {
 586         unsigned timeout = default_timeout;
 587         time_t t;
 588         blocking_lock_record *blr = (blocking_lock_record *)ubi_slFirst(&blocking_lock_queue);
 589
 590         /* note that we avoid the time() syscall if there are no blocking locks */
 591         if (!blr)
 592                 return timeout;
 593
 594         t = time(NULL);
 595
 596         while (blr) {
 597                 if ((blr->expire_time != (time_t)-1) &&
 598                                         (timeout > (blr->expire_time - t))) {
 599                         timeout = blr->expire_time - t;
 600                 }
 601                 blr = (blocking_lock_record *)ubi_slNext(blr);
 602         }
 603
 604         if (timeout < 1)
 605                 timeout = 1;
 606
 607         return timeout;
 608 }
 609
 610 /****************************************************************************
 611  Process the blocking lock queue. Note that this is only called as root.
 612 *****************************************************************************/
 613
 614 void process_blocking_lock_queue(time_t t)
 615 {
 616         blocking_lock_record *blr = (blocking_lock_record *)ubi_slFirst( &blocking_lock_queue );
 617         blocking_lock_record *prev = NULL;
 618
 619         if(blr == NULL)
 620                 return;
 621
 622         /*
 623          * Go through the queue and see if we can get any of the locks.
 624          */
 625
 626         while(blr != NULL) {
 627                 connection_struct *conn = NULL;
 628                 uint16 vuid;
 629                 files_struct *fsp = NULL;
 630
 631                 /*
 632                  * Ensure we don't have any old chain_fsp values
 633                  * sitting around....
 634                  */
 635                 chain_size = 0;
 636                 file_chain_reset();
 637                 fsp = blr->fsp;
 638
 639                 conn = conn_find(SVAL(blr->inbuf,smb_tid));
 640                 vuid = (lp_security() == SEC_SHARE) ? UID_FIELD_INVALID :
 641                                 SVAL(blr->inbuf,smb_uid);
 642
 643                 DEBUG(5,("process_blocking_lock_queue: examining pending lock fnum = %d for file %s\n",
 644                         fsp->fnum, fsp->fsp_name ));
 645
 646                 if((blr->expire_time != -1) && (blr->expire_time <= t)) {
 647                         /*
 648                          * Lock expired - throw away all previously
 649                          * obtained locks and return lock error.
 650                          */
 651                         DEBUG(5,("process_blocking_lock_queue: pending lock fnum = %d for file %s timed out.\n",
 652                                 fsp->fnum, fsp->fsp_name ));
 653
 654                         brl_unlock(fsp->dev, fsp->inode, fsp->fnum,
 655                                 blr->lock_pid, sys_getpid(), conn->cnum,
 656                                 blr->offset, blr->count, True, NULL, NULL);
 657
 658                         blocking_lock_reply_error(blr,NT_STATUS_FILE_LOCK_CONFLICT);
 659                         free_blocking_lock_record((blocking_lock_record *)ubi_slRemNext( &blocking_lock_queue, prev));
 660                         blr = (blocking_lock_record *)(prev ? ubi_slNext(prev) : ubi_slFirst(&blocking_lock_queue));
 661                         continue;
 662                 }
 663
 664                 if(!change_to_user(conn,vuid)) {
 665                         DEBUG(0,("process_blocking_lock_queue: Unable to become user vuid=%d.\n",
 666                                 vuid ));
 667                         /*
 668                          * Remove the entry and return an error to the client.
 669                          */
 670                         blocking_lock_reply_error(blr,NT_STATUS_ACCESS_DENIED);
 671
 672                         brl_unlock(fsp->dev, fsp->inode, fsp->fnum,
 673                                         blr->lock_pid, sys_getpid(), conn->cnum,
 674                                         blr->offset, blr->count, True, NULL, NULL);
 675
 676                         free_blocking_lock_record((blocking_lock_record *)ubi_slRemNext( &blocking_lock_queue, prev));
 677                         blr = (blocking_lock_record *)(prev ? ubi_slNext(prev) : ubi_slFirst(&blocking_lock_queue));
 678                         continue;
 679                 }
 680
 681                 if(!set_current_service(conn,True)) {
 682                         DEBUG(0,("process_blocking_lock_queue: Unable to become service Error was %s.\n", strerror(errno) ));
 683                         /*
 684                          * Remove the entry and return an error to the client.
 685                          */
 686                         blocking_lock_reply_error(blr,NT_STATUS_ACCESS_DENIED);
 687
 688                         brl_unlock(fsp->dev, fsp->inode, fsp->fnum,
 689                                         blr->lock_pid, sys_getpid(), conn->cnum,
 690                                         blr->offset, blr->count, True, NULL, NULL);
 691
 692                         free_blocking_lock_record((blocking_lock_record *)ubi_slRemNext( &blocking_lock_queue, prev));
 693                         blr = (blocking_lock_record *)(prev ? ubi_slNext(prev) : ubi_slFirst(&blocking_lock_queue));
 694                         change_to_root_user();
 695                         continue;
 696                 }
 697
 698                 /*
 699                  * Go through the remaining locks and try and obtain them.
 700                  * The call returns True if all locks were obtained successfully
 701                  * and False if we still need to wait.
 702                  */
 703
 704                 if(blocking_lock_record_process(blr)) {
 705
 706                         brl_unlock(fsp->dev, fsp->inode, fsp->fnum,
 707                                         blr->lock_pid, sys_getpid(), conn->cnum,
 708                                         blr->offset, blr->count, True, NULL, NULL);
 709
 710                         free_blocking_lock_record((blocking_lock_record *)ubi_slRemNext( &blocking_lock_queue, prev));
 711                         blr = (blocking_lock_record *)(prev ? ubi_slNext(prev) : ubi_slFirst(&blocking_lock_queue));
 712                         change_to_root_user();
 713                         continue;
 714                 }
 715
 716                 change_to_root_user();
 717
 718                 /*
 719                  * Move to the next in the list.
 720                  */
 721                 prev = blr;
 722                 blr = (blocking_lock_record *)ubi_slNext(blr);
 723         }
 724 }