source: trunk/samba-3.0.25pre1/source/smbd/blocking.c@ 1

Last change on this file since 1 was 1, checked in by Paul Smedley, 18 years ago

Initial code import
File size: 24.4 KB
Line 
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
25extern 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
32typedef 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. */
49static blocking_lock_record *blocking_lock_queue;
50
51/* dlink list we move cancelled lock records onto. */
52static blocking_lock_record *blocking_lock_cancelled_queue;
53
54/****************************************************************************
55 Destructor for the above structure.
56****************************************************************************/
57
58static 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
68static BOOL in_chained_smb(void)
69{
70 return (chain_size != 0);
71}
72
73static void received_unlock_msg(int msg_type, struct process_id src,
74 void *buf, size_t len,
75 void *private_data);
76
77/****************************************************************************
78 Function to push a blocking lock request onto the lock queue.
79****************************************************************************/
80
81BOOL push_blocking_lock_request( struct byte_range_lock *br_lck,
82 char *inbuf, int length,
83 files_struct *fsp,
84 int lock_timeout,
85 int lock_num,
86 uint32 lock_pid,
87 enum brl_type lock_type,
88 enum brl_flavour lock_flav,
89 SMB_BIG_UINT offset, SMB_BIG_UINT count)
90{
91 static BOOL set_lock_msg;
92 blocking_lock_record *blr;
93 NTSTATUS status;
94
95 if(in_chained_smb() ) {
96 DEBUG(0,("push_blocking_lock_request: cannot queue a chained request (currently).\n"));
97 return False;
98 }
99
100 /*
101 * Now queue an entry on the blocking lock queue. We setup
102 * the expiration time here.
103 */
104
105 if((blr = SMB_MALLOC_P(blocking_lock_record)) == NULL) {
106 DEBUG(0,("push_blocking_lock_request: Malloc fail !\n" ));
107 return False;
108 }
109
110 blr->next = NULL;
111 blr->prev = NULL;
112
113 if((blr->inbuf = (char *)SMB_MALLOC(length)) == NULL) {
114 DEBUG(0,("push_blocking_lock_request: Malloc fail (2)!\n" ));
115 SAFE_FREE(blr);
116 return False;
117 }
118
119 blr->com_type = CVAL(inbuf,smb_com);
120 blr->fsp = fsp;
121 if (lock_timeout == -1) {
122 blr->expire_time.tv_sec = 0;
123 blr->expire_time.tv_usec = 0; /* Never expire. */
124 } else {
125 blr->expire_time = timeval_current_ofs(lock_timeout/1000,
126 (lock_timeout % 1000) * 1000);
127 }
128 blr->lock_num = lock_num;
129 blr->lock_pid = lock_pid;
130 blr->lock_flav = lock_flav;
131 blr->lock_type = lock_type;
132 blr->offset = offset;
133 blr->count = count;
134 memcpy(blr->inbuf, inbuf, length);
135 blr->length = length;
136
137 /* Add a pending lock record for this. */
138 status = brl_lock(br_lck,
139 lock_pid,
140 procid_self(),
141 offset,
142 count,
143 lock_type == READ_LOCK ? PENDING_READ_LOCK : PENDING_WRITE_LOCK,
144 blr->lock_flav,
145 lock_timeout ? True : False); /* blocking_lock. */
146
147 if (!NT_STATUS_IS_OK(status)) {
148 DEBUG(0,("push_blocking_lock_request: failed to add PENDING_LOCK record.\n"));
149 DLIST_REMOVE(blocking_lock_queue, blr);
150 free_blocking_lock_record(blr);
151 return False;
152 }
153
154 DLIST_ADD_END(blocking_lock_queue, blr, blocking_lock_record *);
155
156 /* Ensure we'll receive messages when this is unlocked. */
157 if (!set_lock_msg) {
158 message_register(MSG_SMB_UNLOCK, received_unlock_msg,
159 NULL);
160 set_lock_msg = True;
161 }
162
163 DEBUG(3,("push_blocking_lock_request: lock request length=%d blocked with "
164 "expiry time (%u sec. %u usec) (+%d msec) for fnum = %d, name = %s\n",
165 length, (unsigned int)blr->expire_time.tv_sec,
166 (unsigned int)blr->expire_time.tv_usec, lock_timeout,
167 blr->fsp->fnum, blr->fsp->fsp_name ));
168
169 /* Push the MID of this packet on the signing queue. */
170 srv_defer_sign_response(SVAL(inbuf,smb_mid));
171
172 return True;
173}
174
175/****************************************************************************
176 Return a smd with a given size.
177*****************************************************************************/
178
179static void send_blocking_reply(char *outbuf, int outsize)
180{
181 if(outsize > 4)
182 smb_setlen(outbuf,outsize - 4);
183
184 if (!send_smb(smbd_server_fd(),outbuf))
185 exit_server_cleanly("send_blocking_reply: send_smb failed.");
186}
187
188/****************************************************************************
189 Return a lockingX success SMB.
190*****************************************************************************/
191
192static void reply_lockingX_success(blocking_lock_record *blr)
193{
194 char *outbuf = get_OutBuffer();
195 int bufsize = BUFFER_SIZE;
196 char *inbuf = blr->inbuf;
197 int outsize = 0;
198
199 construct_reply_common(inbuf, outbuf);
200 set_message(outbuf,2,0,True);
201
202 /*
203 * As this message is a lockingX call we must handle
204 * any following chained message correctly.
205 * This is normally handled in construct_reply(),
206 * but as that calls switch_message, we can't use
207 * that here and must set up the chain info manually.
208 */
209
210 outsize = chain_reply(inbuf,outbuf,blr->length,bufsize);
211
212 outsize += chain_size;
213
214 send_blocking_reply(outbuf,outsize);
215}
216
217/****************************************************************************
218 Return a generic lock fail error blocking call.
219*****************************************************************************/
220
221static void generic_blocking_lock_error(blocking_lock_record *blr, NTSTATUS status)
222{
223 char *outbuf = get_OutBuffer();
224 char *inbuf = blr->inbuf;
225 construct_reply_common(inbuf, outbuf);
226
227 /* whenever a timeout is given w2k maps LOCK_NOT_GRANTED to
228 FILE_LOCK_CONFLICT! (tridge) */
229 if (NT_STATUS_EQUAL(status, NT_STATUS_LOCK_NOT_GRANTED)) {
230 status = NT_STATUS_FILE_LOCK_CONFLICT;
231 }
232
233 if (NT_STATUS_EQUAL(status, NT_STATUS_FILE_LOCK_CONFLICT)) {
234 /* Store the last lock error. */
235 files_struct *fsp = blr->fsp;
236
237 fsp->last_lock_failure.context.smbpid = blr->lock_pid;
238 fsp->last_lock_failure.context.tid = fsp->conn->cnum;
239 fsp->last_lock_failure.context.pid = procid_self();
240 fsp->last_lock_failure.start = blr->offset;
241 fsp->last_lock_failure.size = blr->count;
242 fsp->last_lock_failure.fnum = fsp->fnum;
243 fsp->last_lock_failure.lock_type = READ_LOCK; /* Don't care. */
244 fsp->last_lock_failure.lock_flav = blr->lock_flav;
245 }
246
247 ERROR_NT(status);
248 if (!send_smb(smbd_server_fd(),outbuf)) {
249 exit_server_cleanly("generic_blocking_lock_error: send_smb failed.");
250 }
251}
252
253/****************************************************************************
254 Return a lock fail error for a lockingX call. Undo all the locks we have
255 obtained first.
256*****************************************************************************/
257
258static void reply_lockingX_error(blocking_lock_record *blr, NTSTATUS status)
259{
260 char *inbuf = blr->inbuf;
261 files_struct *fsp = blr->fsp;
262 uint16 num_ulocks = SVAL(inbuf,smb_vwv6);
263 SMB_BIG_UINT count = (SMB_BIG_UINT)0, offset = (SMB_BIG_UINT) 0;
264 uint32 lock_pid;
265 unsigned char locktype = CVAL(inbuf,smb_vwv3);
266 BOOL large_file_format = (locktype & LOCKING_ANDX_LARGE_FILES);
267 char *data;
268 int i;
269
270 data = smb_buf(inbuf) + ((large_file_format ? 20 : 10)*num_ulocks);
271
272 /*
273 * Data now points at the beginning of the list
274 * of smb_lkrng structs.
275 */
276
277 /*
278 * Ensure we don't do a remove on the lock that just failed,
279 * as under POSIX rules, if we have a lock already there, we
280 * will delete it (and we shouldn't) .....
281 */
282
283 for(i = blr->lock_num - 1; i >= 0; i--) {
284 BOOL err;
285
286 lock_pid = get_lock_pid( data, i, large_file_format);
287 count = get_lock_count( data, i, large_file_format);
288 offset = get_lock_offset( data, i, large_file_format, &err);
289
290 /*
291 * We know err cannot be set as if it was the lock
292 * request would never have been queued. JRA.
293 */
294
295 do_unlock(fsp,
296 lock_pid,
297 count,
298 offset,
299 WINDOWS_LOCK);
300 }
301
302 generic_blocking_lock_error(blr, status);
303}
304
305/****************************************************************************
306 Return a lock fail error.
307*****************************************************************************/
308
309static void blocking_lock_reply_error(blocking_lock_record *blr, NTSTATUS status)
310{
311 switch(blr->com_type) {
312 case SMBlockingX:
313 reply_lockingX_error(blr, status);
314 break;
315 case SMBtrans2:
316 case SMBtranss2:
317 {
318 char *outbuf = get_OutBuffer();
319 char *inbuf = blr->inbuf;
320 construct_reply_common(inbuf, outbuf);
321 /* construct_reply_common has done us the favor to pre-fill the
322 * command field with SMBtranss2 which is wrong :-)
323 */
324 SCVAL(outbuf,smb_com,SMBtrans2);
325 ERROR_NT(status);
326 if (!send_smb(smbd_server_fd(),outbuf)) {
327 exit_server_cleanly("blocking_lock_reply_error: send_smb failed.");
328 }
329 break;
330 }
331 default:
332 DEBUG(0,("blocking_lock_reply_error: PANIC - unknown type on blocking lock queue - exiting.!\n"));
333 exit_server("PANIC - unknown type on blocking lock queue");
334 }
335}
336
337/****************************************************************************
338 Attempt to finish off getting all pending blocking locks for a lockingX call.
339 Returns True if we want to be removed from the list.
340*****************************************************************************/
341
342static BOOL process_lockingX(blocking_lock_record *blr)
343{
344 char *inbuf = blr->inbuf;
345 unsigned char locktype = CVAL(inbuf,smb_vwv3);
346 files_struct *fsp = blr->fsp;
347 uint16 num_ulocks = SVAL(inbuf,smb_vwv6);
348 uint16 num_locks = SVAL(inbuf,smb_vwv7);
349 SMB_BIG_UINT count = (SMB_BIG_UINT)0, offset = (SMB_BIG_UINT)0;
350 uint32 lock_pid;
351 BOOL large_file_format = (locktype & LOCKING_ANDX_LARGE_FILES);
352 char *data;
353 NTSTATUS status = NT_STATUS_OK;
354
355 data = smb_buf(inbuf) + ((large_file_format ? 20 : 10)*num_ulocks);
356
357 /*
358 * Data now points at the beginning of the list
359 * of smb_lkrng structs.
360 */
361
362 for(; blr->lock_num < num_locks; blr->lock_num++) {
363 struct byte_range_lock *br_lck = NULL;
364 BOOL err;
365
366 lock_pid = get_lock_pid( data, blr->lock_num, large_file_format);
367 count = get_lock_count( data, blr->lock_num, large_file_format);
368 offset = get_lock_offset( data, blr->lock_num, large_file_format, &err);
369
370 /*
371 * We know err cannot be set as if it was the lock
372 * request would never have been queued. JRA.
373 */
374 errno = 0;
375 br_lck = do_lock(fsp,
376 lock_pid,
377 count,
378 offset,
379 ((locktype & LOCKING_ANDX_SHARED_LOCK) ?
380 READ_LOCK : WRITE_LOCK),
381 WINDOWS_LOCK,
382 True,
383 &status);
384
385 TALLOC_FREE(br_lck);
386
387 if (NT_STATUS_IS_ERR(status)) {
388 break;
389 }
390 }
391
392 if(blr->lock_num == num_locks) {
393 /*
394 * Success - we got all the locks.
395 */
396
397 DEBUG(3,("process_lockingX file = %s, fnum=%d type=%d num_locks=%d\n",
398 fsp->fsp_name, fsp->fnum, (unsigned int)locktype, num_locks) );
399
400 reply_lockingX_success(blr);
401 return True;
402 } else if (!NT_STATUS_EQUAL(status,NT_STATUS_LOCK_NOT_GRANTED) &&
403 !NT_STATUS_EQUAL(status,NT_STATUS_FILE_LOCK_CONFLICT)) {
404 /*
405 * We have other than a "can't get lock"
406 * error. Free any locks we had and return an error.
407 * Return True so we get dequeued.
408 */
409
410 blocking_lock_reply_error(blr, status);
411 return True;
412 }
413
414 /*
415 * Still can't get all the locks - keep waiting.
416 */
417
418 DEBUG(10,("process_lockingX: only got %d locks of %d needed for file %s, fnum = %d. \
419Waiting....\n",
420 blr->lock_num, num_locks, fsp->fsp_name, fsp->fnum));
421
422 return False;
423}
424
425/****************************************************************************
426 Attempt to get the posix lock request from a SMBtrans2 call.
427 Returns True if we want to be removed from the list.
428*****************************************************************************/
429
430static BOOL process_trans2(blocking_lock_record *blr)
431{
432 char *inbuf = blr->inbuf;
433 char *outbuf;
434 char params[2];
435 NTSTATUS status;
436 struct byte_range_lock *br_lck = do_lock(blr->fsp,
437 blr->lock_pid,
438 blr->count,
439 blr->offset,
440 blr->lock_type,
441 blr->lock_flav,
442 True,
443 &status);
444 TALLOC_FREE(br_lck);
445
446 if (!NT_STATUS_IS_OK(status)) {
447 if (ERROR_WAS_LOCK_DENIED(status)) {
448 /* Still can't get the lock, just keep waiting. */
449 return False;
450 }
451 /*
452 * We have other than a "can't get lock"
453 * error. Send an error and return True so we get dequeued.
454 */
455 blocking_lock_reply_error(blr, status);
456 return True;
457 }
458
459 /* We finally got the lock, return success. */
460 outbuf = get_OutBuffer();
461 construct_reply_common(inbuf, outbuf);
462 SCVAL(outbuf,smb_com,SMBtrans2);
463 SSVAL(params,0,0);
464 /* Fake up max_data_bytes here - we know it fits. */
465 send_trans2_replies(outbuf, max_send, params, 2, NULL, 0, 0xffff);
466 return True;
467}
468
469
470/****************************************************************************
471 Process a blocking lock SMB.
472 Returns True if we want to be removed from the list.
473*****************************************************************************/
474
475static BOOL blocking_lock_record_process(blocking_lock_record *blr)
476{
477 switch(blr->com_type) {
478 case SMBlockingX:
479 return process_lockingX(blr);
480 case SMBtrans2:
481 case SMBtranss2:
482 return process_trans2(blr);
483 default:
484 DEBUG(0,("blocking_lock_record_process: PANIC - unknown type on blocking lock queue - exiting.!\n"));
485 exit_server("PANIC - unknown type on blocking lock queue");
486 }
487 return False; /* Keep compiler happy. */
488}
489
490/****************************************************************************
491 Cancel entries by fnum from the blocking lock pending queue.
492*****************************************************************************/
493
494void cancel_pending_lock_requests_by_fid(files_struct *fsp, struct byte_range_lock *br_lck)
495{
496 blocking_lock_record *blr, *next = NULL;
497
498 for(blr = blocking_lock_queue; blr; blr = next) {
499 next = blr->next;
500 if(blr->fsp->fnum == fsp->fnum) {
501 unsigned char locktype = 0;
502
503 if (blr->com_type == SMBlockingX) {
504 locktype = CVAL(blr->inbuf,smb_vwv3);
505 }
506
507 if (br_lck) {
508 DEBUG(10,("remove_pending_lock_requests_by_fid - removing request type %d for \
509file %s fnum = %d\n", blr->com_type, fsp->fsp_name, fsp->fnum ));
510
511 brl_lock_cancel(br_lck,
512 blr->lock_pid,
513 procid_self(),
514 blr->offset,
515 blr->count,
516 blr->lock_flav);
517
518 blocking_lock_cancel(fsp,
519 blr->lock_pid,
520 blr->offset,
521 blr->count,
522 blr->lock_flav,
523 locktype,
524 NT_STATUS_RANGE_NOT_LOCKED);
525 }
526 }
527 }
528}
529
530/****************************************************************************
531 Delete entries by mid from the blocking lock pending queue. Always send reply.
532*****************************************************************************/
533
534void remove_pending_lock_requests_by_mid(int mid)
535{
536 blocking_lock_record *blr, *next = NULL;
537
538 for(blr = blocking_lock_queue; blr; blr = next) {
539 next = blr->next;
540 if(SVAL(blr->inbuf,smb_mid) == mid) {
541 files_struct *fsp = blr->fsp;
542 struct byte_range_lock *br_lck = brl_get_locks(NULL, fsp);
543
544 if (br_lck) {
545 DEBUG(10,("remove_pending_lock_requests_by_mid - removing request type %d for \
546file %s fnum = %d\n", blr->com_type, fsp->fsp_name, fsp->fnum ));
547
548 brl_lock_cancel(br_lck,
549 blr->lock_pid,
550 procid_self(),
551 blr->offset,
552 blr->count,
553 blr->lock_flav);
554 TALLOC_FREE(br_lck);
555 }
556
557 blocking_lock_reply_error(blr,NT_STATUS_FILE_LOCK_CONFLICT);
558 DLIST_REMOVE(blocking_lock_queue, blr);
559 free_blocking_lock_record(blr);
560 }
561 }
562}
563
564/****************************************************************************
565 Is this mid a blocking lock request on the queue ?
566*****************************************************************************/
567
568BOOL blocking_lock_was_deferred(int mid)
569{
570 blocking_lock_record *blr, *next = NULL;
571
572 for(blr = blocking_lock_queue; blr; blr = next) {
573 next = blr->next;
574 if(SVAL(blr->inbuf,smb_mid) == mid) {
575 return True;
576 }
577 }
578 return False;
579}
580
581/****************************************************************************
582 Set a flag as an unlock request affects one of our pending locks.
583*****************************************************************************/
584
585static void received_unlock_msg(int msg_type, struct process_id src,
586 void *buf, size_t len,
587 void *private_data)
588{
589 DEBUG(10,("received_unlock_msg\n"));
590 process_blocking_lock_queue();
591}
592
593/****************************************************************************
594 Return the number of milliseconds to the next blocking locks timeout, or default_timeout
595*****************************************************************************/
596
597unsigned int blocking_locks_timeout_ms(unsigned int default_timeout_ms)
598{
599 unsigned int timeout_ms = default_timeout_ms;
600 struct timeval tv_curr;
601 SMB_BIG_INT min_tv_dif_us = 0x7FFFFFFF; /* A large +ve number. */
602 blocking_lock_record *blr = blocking_lock_queue;
603
604 /* note that we avoid the GetTimeOfDay() syscall if there are no blocking locks */
605 if (!blr) {
606 return timeout_ms;
607 }
608
609 tv_curr = timeval_current();
610
611 for (; blr; blr = blr->next) {
612 SMB_BIG_INT tv_dif_us;
613
614 if (timeval_is_zero(&blr->expire_time)) {
615 continue; /* Never timeout. */
616 }
617
618 tv_dif_us = usec_time_diff(&blr->expire_time, &tv_curr);
619 min_tv_dif_us = MIN(min_tv_dif_us, tv_dif_us);
620 }
621
622 if (min_tv_dif_us < 0) {
623 min_tv_dif_us = 0;
624 }
625
626 timeout_ms = (unsigned int)(min_tv_dif_us / (SMB_BIG_INT)1000);
627
628 if (timeout_ms < 1) {
629 timeout_ms = 1;
630 }
631
632 DEBUG(10,("blocking_locks_timeout_ms: returning %u\n", timeout_ms));
633
634 return timeout_ms;
635}
636
637/****************************************************************************
638 Process the blocking lock queue. Note that this is only called as root.
639*****************************************************************************/
640
641void process_blocking_lock_queue(void)
642{
643 struct timeval tv_curr = timeval_current();
644 blocking_lock_record *blr, *next = NULL;
645
646 /*
647 * Go through the queue and see if we can get any of the locks.
648 */
649
650 for (blr = blocking_lock_queue; blr; blr = next) {
651 connection_struct *conn = NULL;
652 uint16 vuid;
653 files_struct *fsp = NULL;
654
655 next = blr->next;
656
657 /*
658 * Ensure we don't have any old chain_fsp values
659 * sitting around....
660 */
661 chain_size = 0;
662 file_chain_reset();
663 fsp = blr->fsp;
664
665 conn = conn_find(SVAL(blr->inbuf,smb_tid));
666 vuid = (lp_security() == SEC_SHARE) ? UID_FIELD_INVALID :
667 SVAL(blr->inbuf,smb_uid);
668
669 DEBUG(5,("process_blocking_lock_queue: examining pending lock fnum = %d for file %s\n",
670 fsp->fnum, fsp->fsp_name ));
671
672 if (!timeval_is_zero(&blr->expire_time) && timeval_compare(&blr->expire_time, &tv_curr) <= 0) {
673 struct byte_range_lock *br_lck = brl_get_locks(NULL, fsp);
674
675 /*
676 * Lock expired - throw away all previously
677 * obtained locks and return lock error.
678 */
679
680 if (br_lck) {
681 DEBUG(5,("process_blocking_lock_queue: pending lock fnum = %d for file %s timed out.\n",
682 fsp->fnum, fsp->fsp_name ));
683
684 brl_lock_cancel(br_lck,
685 blr->lock_pid,
686 procid_self(),
687 blr->offset,
688 blr->count,
689 blr->lock_flav);
690 TALLOC_FREE(br_lck);
691 }
692
693 blocking_lock_reply_error(blr,NT_STATUS_FILE_LOCK_CONFLICT);
694 DLIST_REMOVE(blocking_lock_queue, blr);
695 free_blocking_lock_record(blr);
696 continue;
697 }
698
699 if(!change_to_user(conn,vuid)) {
700 struct byte_range_lock *br_lck = brl_get_locks(NULL, fsp);
701
702 /*
703 * Remove the entry and return an error to the client.
704 */
705
706 if (br_lck) {
707 brl_lock_cancel(br_lck,
708 blr->lock_pid,
709 procid_self(),
710 blr->offset,
711 blr->count,
712 blr->lock_flav);
713 TALLOC_FREE(br_lck);
714 }
715
716 DEBUG(0,("process_blocking_lock_queue: Unable to become user vuid=%d.\n",
717 vuid ));
718 blocking_lock_reply_error(blr,NT_STATUS_ACCESS_DENIED);
719 DLIST_REMOVE(blocking_lock_queue, blr);
720 free_blocking_lock_record(blr);
721 continue;
722 }
723
724 if(!set_current_service(conn,SVAL(blr->inbuf,smb_flg),True)) {
725 struct byte_range_lock *br_lck = brl_get_locks(NULL, fsp);
726
727 /*
728 * Remove the entry and return an error to the client.
729 */
730
731 if (br_lck) {
732 brl_lock_cancel(br_lck,
733 blr->lock_pid,
734 procid_self(),
735 blr->offset,
736 blr->count,
737 blr->lock_flav);
738 TALLOC_FREE(br_lck);
739 }
740
741 DEBUG(0,("process_blocking_lock_queue: Unable to become service Error was %s.\n", strerror(errno) ));
742 blocking_lock_reply_error(blr,NT_STATUS_ACCESS_DENIED);
743 DLIST_REMOVE(blocking_lock_queue, blr);
744 free_blocking_lock_record(blr);
745 change_to_root_user();
746 continue;
747 }
748
749 /*
750 * Go through the remaining locks and try and obtain them.
751 * The call returns True if all locks were obtained successfully
752 * and False if we still need to wait.
753 */
754
755 if(blocking_lock_record_process(blr)) {
756 struct byte_range_lock *br_lck = brl_get_locks(NULL, fsp);
757
758 if (br_lck) {
759 brl_lock_cancel(br_lck,
760 blr->lock_pid,
761 procid_self(),
762 blr->offset,
763 blr->count,
764 blr->lock_flav);
765 TALLOC_FREE(br_lck);
766 }
767
768 DLIST_REMOVE(blocking_lock_queue, blr);
769 free_blocking_lock_record(blr);
770 }
771 change_to_root_user();
772 }
773}
774
775/****************************************************************************
776 Handle a cancel message. Lock already moved onto the cancel queue.
777*****************************************************************************/
778
779#define MSG_BLOCKING_LOCK_CANCEL_SIZE (sizeof(blocking_lock_record *) + sizeof(NTSTATUS))
780
781static void process_blocking_lock_cancel_message(int msg_type,
782 struct process_id src,
783 void *buf, size_t len,
784 void *private_data)
785{
786 NTSTATUS err;
787 const char *msg = (const char *)buf;
788 blocking_lock_record *blr;
789
790 if (buf == NULL) {
791 smb_panic("process_blocking_lock_cancel_message: null msg\n");
792 }
793
794 if (len != MSG_BLOCKING_LOCK_CANCEL_SIZE) {
795 DEBUG(0, ("process_blocking_lock_cancel_message: "
796 "Got invalid msg len %d\n", (int)len));
797 smb_panic("process_blocking_lock_cancel_message: bad msg\n");
798 }
799
800 memcpy(&blr, msg, sizeof(blr));
801 memcpy(&err, &msg[sizeof(blr)], sizeof(NTSTATUS));
802
803 DEBUG(10,("process_blocking_lock_cancel_message: returning error %s\n",
804 nt_errstr(err) ));
805
806 blocking_lock_reply_error(blr, err);
807 DLIST_REMOVE(blocking_lock_cancelled_queue, blr);
808 free_blocking_lock_record(blr);
809}
810
811/****************************************************************************
812 Send ourselves a blocking lock cancelled message. Handled asynchronously above.
813*****************************************************************************/
814
815BOOL blocking_lock_cancel(files_struct *fsp,
816 uint32 lock_pid,
817 SMB_BIG_UINT offset,
818 SMB_BIG_UINT count,
819 enum brl_flavour lock_flav,
820 unsigned char locktype,
821 NTSTATUS err)
822{
823 static BOOL initialized;
824 char msg[MSG_BLOCKING_LOCK_CANCEL_SIZE];
825 blocking_lock_record *blr;
826
827 if (!initialized) {
828 /* Register our message. */
829 message_register(MSG_SMB_BLOCKING_LOCK_CANCEL,
830 process_blocking_lock_cancel_message,
831 NULL);
832
833 initialized = True;
834 }
835
836 for (blr = blocking_lock_queue; blr; blr = blr->next) {
837 if (fsp == blr->fsp &&
838 lock_pid == blr->lock_pid &&
839 offset == blr->offset &&
840 count == blr->count &&
841 lock_flav == blr->lock_flav) {
842 break;
843 }
844 }
845
846 if (!blr) {
847 return False;
848 }
849
850 /* Check the flags are right. */
851 if (blr->com_type == SMBlockingX &&
852 (locktype & LOCKING_ANDX_LARGE_FILES) !=
853 (CVAL(blr->inbuf,smb_vwv3) & LOCKING_ANDX_LARGE_FILES)) {
854 return False;
855 }
856
857 /* Move to cancelled queue. */
858 DLIST_REMOVE(blocking_lock_queue, blr);
859 DLIST_ADD(blocking_lock_cancelled_queue, blr);
860
861 /* Create the message. */
862 memcpy(msg, &blr, sizeof(blr));
863 memcpy(&msg[sizeof(blr)], &err, sizeof(NTSTATUS));
864
865 message_send_pid(pid_to_procid(sys_getpid()),
866 MSG_SMB_BLOCKING_LOCK_CANCEL,
867 &msg, sizeof(msg), True);
868
869 return True;
870}
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