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