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source: branches/samba-3.3.x/source/smbd/blocking.c@ 432

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Last change on this file since 432 was 370, checked in by Herwig Bauernfeind, 16 years ago
Update Samba 3.3 to 3.3.10 (source)
File size: 27.0 KB

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1	/*
2	Unix SMB/CIFS implementation.
3	Blocking Locking functions
4	Copyright (C) Jeremy Allison 1998-2003
5
6	This program is free software; you can redistribute it and/or modify
7	it under the terms of the GNU General Public License as published by
8	the Free Software Foundation; either version 3 of the License, or
9	(at your option) any later version.
10
11	This program is distributed in the hope that it will be useful,
12	but WITHOUT ANY WARRANTY; without even the implied warranty of
13	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14	GNU General Public License for more details.
15
16	You should have received a copy of the GNU General Public License
17	along with this program. If not, see <http://www.gnu.org/licenses/>.
18	*/
19
20	#include "includes.h"
21	#undef DBGC_CLASS
22	#define DBGC_CLASS DBGC_LOCKING
23
24	/****************************************************************************
25	This is the structure to queue to implement blocking locks.
26	notify. It consists of the requesting SMB and the expiry time.
27	*****************************************************************************/
28
29	typedef struct _blocking_lock_record {
30	struct _blocking_lock_record *next;
31	struct _blocking_lock_record *prev;
32	int com_type;
33	files_struct *fsp;
34	struct timeval expire_time;
35	int lock_num;
36	SMB_BIG_UINT offset;
37	SMB_BIG_UINT count;
38	uint32 lock_pid;
39	uint32 blocking_pid; /* PID that blocks us. */
40	enum brl_flavour lock_flav;
41	enum brl_type lock_type;
42	char *inbuf;
43	int length;
44	bool encrypted;
45	} blocking_lock_record;
46
47	/* dlink list we store pending lock records on. */
48	static blocking_lock_record *blocking_lock_queue;
49
50	/* dlink list we move cancelled lock records onto. */
51	static blocking_lock_record *blocking_lock_cancelled_queue;
52
53	/* The event that makes us process our blocking lock queue */
54	static struct timed_event *brl_timeout;
55
56	/****************************************************************************
57	Destructor for the above structure.
58	****************************************************************************/
59
60	static void free_blocking_lock_record(blocking_lock_record *blr)
61	{
62	SAFE_FREE(blr->inbuf);
63	SAFE_FREE(blr);
64	}
65
66	/****************************************************************************
67	Determine if this is a secondary element of a chained SMB.
68	**************************************************************************/
69
70	static bool in_chained_smb(void)
71	{
72	return (chain_size != 0);
73	}
74
75	static void received_unlock_msg(struct messaging_context *msg,
76	void *private_data,
77	uint32_t msg_type,
78	struct server_id server_id,
79	DATA_BLOB *data);
80	static void process_blocking_lock_queue(void);
81
82	static void brl_timeout_fn(struct event_context *event_ctx,
83	struct timed_event *te,
84	struct timeval now,
85	void *private_data)
86	{
87	SMB_ASSERT(brl_timeout == te);
88	TALLOC_FREE(brl_timeout);
89
90	change_to_root_user(); /* TODO: Possibly run all timed events as
91	* root */
92
93	process_blocking_lock_queue();
94	}
95
96	/****************************************************************************
97	We need a version of timeval_min that treats zero timval as infinite.
98	****************************************************************************/
99
100	static struct timeval timeval_brl_min(const struct timeval *tv1,
101	const struct timeval *tv2)
102	{
103	if (timeval_is_zero(tv1)) {
104	return *tv2;
105	}
106	if (timeval_is_zero(tv2)) {
107	return *tv1;
108	}
109	return timeval_min(tv1, tv2);
110	}
111
112	/****************************************************************************
113	After a change to blocking_lock_queue, recalculate the timed_event for the
114	next processing.
115	****************************************************************************/
116
117	static bool recalc_brl_timeout(void)
118	{
119	blocking_lock_record *brl;
120	struct timeval next_timeout;
121
122	TALLOC_FREE(brl_timeout);
123
124	next_timeout = timeval_zero();
125
126	for (brl = blocking_lock_queue; brl; brl = brl->next) {
127	if (timeval_is_zero(&brl->expire_time)) {
128	/*
129	* If we're blocked on pid 0xFFFFFFFF this is
130	* a POSIX lock, so calculate a timeout of
131	* 10 seconds into the future.
132	*/
133	if (brl->blocking_pid == 0xFFFFFFFF) {
134	struct timeval psx_to = timeval_current_ofs(10, 0);
135	next_timeout = timeval_brl_min(&next_timeout, &psx_to);
136	}
137
138	continue;
139	}
140
141	next_timeout = timeval_brl_min(&next_timeout, &brl->expire_time);
142	}
143
144	if (timeval_is_zero(&next_timeout)) {
145	return True;
146	}
147
148	if (!(brl_timeout = event_add_timed(smbd_event_context(), NULL,
149	next_timeout,
150	brl_timeout_fn, NULL))) {
151	return False;
152	}
153
154	return True;
155	}
156
157
158	/****************************************************************************
159	Function to push a blocking lock request onto the lock queue.
160	****************************************************************************/
161
162	bool push_blocking_lock_request( struct byte_range_lock *br_lck,
163	const struct smb_request *req,
164	files_struct *fsp,
165	int lock_timeout,
166	int lock_num,
167	uint32 lock_pid,
168	enum brl_type lock_type,
169	enum brl_flavour lock_flav,
170	SMB_BIG_UINT offset,
171	SMB_BIG_UINT count,
172	uint32 blocking_pid)
173	{
174	static bool set_lock_msg;
175	size_t length = smb_len(req->inbuf)+4;
176	blocking_lock_record *blr;
177	NTSTATUS status;
178
179	if(in_chained_smb() ) {
180	DEBUG(0,("push_blocking_lock_request: cannot queue a chained request (currently).\n"));
181	return False;
182	}
183
184	/*
185	* Now queue an entry on the blocking lock queue. We setup
186	* the expiration time here.
187	*/
188
189	if((blr = SMB_MALLOC_P(blocking_lock_record)) == NULL) {
190	DEBUG(0,("push_blocking_lock_request: Malloc fail !\n" ));
191	return False;
192	}
193
194	blr->next = NULL;
195	blr->prev = NULL;
196
197	if((blr->inbuf = (char *)SMB_MALLOC(length)) == NULL) {
198	DEBUG(0,("push_blocking_lock_request: Malloc fail (2)!\n" ));
199	SAFE_FREE(blr);
200	return False;
201	}
202
203	blr->com_type = CVAL(req->inbuf,smb_com);
204	blr->fsp = fsp;
205	if (lock_timeout == -1) {
206	blr->expire_time.tv_sec = 0;
207	blr->expire_time.tv_usec = 0; /* Never expire. */
208	} else {
209	blr->expire_time = timeval_current_ofs(lock_timeout/1000,
210	(lock_timeout % 1000) * 1000);
211	}
212	blr->lock_num = lock_num;
213	blr->lock_pid = lock_pid;
214	blr->blocking_pid = blocking_pid;
215	blr->lock_flav = lock_flav;
216	blr->lock_type = lock_type;
217	blr->offset = offset;
218	blr->count = count;
219	memcpy(blr->inbuf, req->inbuf, length);
220	blr->length = length;
221	blr->encrypted = req->encrypted;
222
223	/* Add a pending lock record for this. */
224	status = brl_lock(smbd_messaging_context(), br_lck,
225	lock_pid,
226	procid_self(),
227	offset,
228	count,
229	lock_type == READ_LOCK ? PENDING_READ_LOCK : PENDING_WRITE_LOCK,
230	blr->lock_flav,
231	lock_timeout ? True : False, /* blocking_lock. */
232	NULL);
233
234	if (!NT_STATUS_IS_OK(status)) {
235	DEBUG(0,("push_blocking_lock_request: failed to add PENDING_LOCK record.\n"));
236	DLIST_REMOVE(blocking_lock_queue, blr);
237	free_blocking_lock_record(blr);
238	return False;
239	}
240
241	DLIST_ADD_END(blocking_lock_queue, blr, blocking_lock_record *);
242	recalc_brl_timeout();
243
244	/* Ensure we'll receive messages when this is unlocked. */
245	if (!set_lock_msg) {
246	messaging_register(smbd_messaging_context(), NULL,
247	MSG_SMB_UNLOCK, received_unlock_msg);
248	set_lock_msg = True;
249	}
250
251	DEBUG(3,("push_blocking_lock_request: lock request length=%u blocked with "
252	"expiry time (%u sec. %u usec) (+%d msec) for fnum = %d, name = %s\n",
253	(unsigned int)length, (unsigned int)blr->expire_time.tv_sec,
254	(unsigned int)blr->expire_time.tv_usec, lock_timeout,
255	blr->fsp->fnum, blr->fsp->fsp_name ));
256
257	/* Push the MID of this packet on the signing queue. */
258	srv_defer_sign_response(SVAL(req->inbuf,smb_mid));
259
260	return True;
261	}
262
263	/****************************************************************************
264	Return a lockingX success SMB.
265	*****************************************************************************/
266
267	static void reply_lockingX_success(blocking_lock_record *blr)
268	{
269	struct smb_request *req;
270
271	if (!(req = talloc(talloc_tos(), struct smb_request))) {
272	smb_panic("Could not allocate smb_request");
273	}
274
275	init_smb_request(req, (uint8 *)blr->inbuf, 0, blr->encrypted);
276	reply_outbuf(req, 2, 0);
277
278	/*
279	* As this message is a lockingX call we must handle
280	* any following chained message correctly.
281	* This is normally handled in construct_reply(),
282	* but as that calls switch_message, we can't use
283	* that here and must set up the chain info manually.
284	*/
285
286	chain_reply(req);
287
288	if (!srv_send_smb(smbd_server_fd(),
289	(char *)req->outbuf,
290	IS_CONN_ENCRYPTED(blr->fsp->conn))) {
291	exit_server_cleanly("send_blocking_reply: srv_send_smb failed.");
292	}
293	}
294
295	/****************************************************************************
296	Return a generic lock fail error blocking call.
297	*****************************************************************************/
298
299	static void generic_blocking_lock_error(blocking_lock_record *blr, NTSTATUS status)
300	{
301	char outbuf[smb_size];
302	char *inbuf = blr->inbuf;
303
304	construct_reply_common(inbuf, outbuf);
305
306	/* whenever a timeout is given w2k maps LOCK_NOT_GRANTED to
307	FILE_LOCK_CONFLICT! (tridge) */
308	if (NT_STATUS_EQUAL(status, NT_STATUS_LOCK_NOT_GRANTED)) {
309	status = NT_STATUS_FILE_LOCK_CONFLICT;
310	}
311
312	if (NT_STATUS_EQUAL(status, NT_STATUS_FILE_LOCK_CONFLICT)) {
313	/* Store the last lock error. */
314	files_struct *fsp = blr->fsp;
315
316	if (fsp) {
317	fsp->last_lock_failure.context.smbpid = blr->lock_pid;
318	fsp->last_lock_failure.context.tid = fsp->conn->cnum;
319	fsp->last_lock_failure.context.pid = procid_self();
320	fsp->last_lock_failure.start = blr->offset;
321	fsp->last_lock_failure.size = blr->count;
322	fsp->last_lock_failure.fnum = fsp->fnum;
323	fsp->last_lock_failure.lock_type = READ_LOCK; /* Don't care. */
324	fsp->last_lock_failure.lock_flav = blr->lock_flav;
325	}
326	}
327
328	ERROR_NT(status);
329	if (!srv_send_smb(smbd_server_fd(),outbuf, blr->encrypted)) {
330	exit_server_cleanly("generic_blocking_lock_error: srv_send_smb failed.");
331	}
332	}
333
334	/****************************************************************************
335	Return a lock fail error for a lockingX call. Undo all the locks we have
336	obtained first.
337	*****************************************************************************/
338
339	static void reply_lockingX_error(blocking_lock_record *blr, NTSTATUS status)
340	{
341	char *inbuf = blr->inbuf;
342	files_struct *fsp = blr->fsp;
343	uint16 num_ulocks = SVAL(inbuf,smb_vwv6);
344	SMB_BIG_UINT count = (SMB_BIG_UINT)0, offset = (SMB_BIG_UINT) 0;
345	uint32 lock_pid;
346	unsigned char locktype = CVAL(inbuf,smb_vwv3);
347	bool large_file_format = (locktype & LOCKING_ANDX_LARGE_FILES);
348	char *data;
349	int i;
350
351	data = smb_buf(inbuf) + ((large_file_format ? 20 : 10)*num_ulocks);
352
353	/*
354	* Data now points at the beginning of the list
355	* of smb_lkrng structs.
356	*/
357
358	/*
359	* Ensure we don't do a remove on the lock that just failed,
360	* as under POSIX rules, if we have a lock already there, we
361	* will delete it (and we shouldn't) .....
362	*/
363
364	for(i = blr->lock_num - 1; i >= 0; i--) {
365	bool err;
366
367	lock_pid = get_lock_pid( data, i, large_file_format);
368	count = get_lock_count( data, i, large_file_format);
369	offset = get_lock_offset( data, i, large_file_format, &err);
370
371	/*
372	* We know err cannot be set as if it was the lock
373	* request would never have been queued. JRA.
374	*/
375
376	do_unlock(smbd_messaging_context(),
377	fsp,
378	lock_pid,
379	count,
380	offset,
381	WINDOWS_LOCK);
382	}
383
384	generic_blocking_lock_error(blr, status);
385	}
386
387	/****************************************************************************
388	Return a lock fail error.
389	*****************************************************************************/
390
391	static void blocking_lock_reply_error(blocking_lock_record *blr, NTSTATUS status)
392	{
393	switch(blr->com_type) {
394	case SMBlockingX:
395	reply_lockingX_error(blr, status);
396	break;
397	case SMBtrans2:
398	case SMBtranss2:
399	{
400	char outbuf[smb_size];
401	char *inbuf = blr->inbuf;
402	construct_reply_common(inbuf, outbuf);
403	/* construct_reply_common has done us the favor to pre-fill the
404	* command field with SMBtranss2 which is wrong :-)
405	*/
406	SCVAL(outbuf,smb_com,SMBtrans2);
407	ERROR_NT(status);
408	if (!srv_send_smb(smbd_server_fd(),
409	outbuf,
410	IS_CONN_ENCRYPTED(blr->fsp->conn))) {
411	exit_server_cleanly("blocking_lock_reply_error: srv_send_smb failed.");
412	}
413	break;
414	}
415	default:
416	DEBUG(0,("blocking_lock_reply_error: PANIC - unknown type on blocking lock queue - exiting.!\n"));
417	exit_server("PANIC - unknown type on blocking lock queue");
418	}
419	}
420
421	/****************************************************************************
422	Attempt to finish off getting all pending blocking locks for a lockingX call.
423	Returns True if we want to be removed from the list.
424	*****************************************************************************/
425
426	static bool process_lockingX(blocking_lock_record *blr)
427	{
428	char *inbuf = blr->inbuf;
429	unsigned char locktype = CVAL(inbuf,smb_vwv3);
430	files_struct *fsp = blr->fsp;
431	uint16 num_ulocks = SVAL(inbuf,smb_vwv6);
432	uint16 num_locks = SVAL(inbuf,smb_vwv7);
433	SMB_BIG_UINT count = (SMB_BIG_UINT)0, offset = (SMB_BIG_UINT)0;
434	uint32 lock_pid;
435	bool large_file_format = (locktype & LOCKING_ANDX_LARGE_FILES);
436	char *data;
437	NTSTATUS status = NT_STATUS_OK;
438
439	data = smb_buf(inbuf) + ((large_file_format ? 20 : 10)*num_ulocks);
440
441	/*
442	* Data now points at the beginning of the list
443	* of smb_lkrng structs.
444	*/
445
446	for(; blr->lock_num < num_locks; blr->lock_num++) {
447	struct byte_range_lock *br_lck = NULL;
448	bool err;
449
450	lock_pid = get_lock_pid( data, blr->lock_num, large_file_format);
451	count = get_lock_count( data, blr->lock_num, large_file_format);
452	offset = get_lock_offset( data, blr->lock_num, large_file_format, &err);
453
454	/*
455	* We know err cannot be set as if it was the lock
456	* request would never have been queued. JRA.
457	*/
458	errno = 0;
459	br_lck = do_lock(smbd_messaging_context(),
460	fsp,
461	lock_pid,
462	count,
463	offset,
464	((locktype & LOCKING_ANDX_SHARED_LOCK) ?
465	READ_LOCK : WRITE_LOCK),
466	WINDOWS_LOCK,
467	True,
468	&status,
469	&blr->blocking_pid);
470
471	TALLOC_FREE(br_lck);
472
473	if (NT_STATUS_IS_ERR(status)) {
474	break;
475	}
476	}
477
478	if(blr->lock_num == num_locks) {
479	/*
480	* Success - we got all the locks.
481	*/
482
483	DEBUG(3,("process_lockingX file = %s, fnum=%d type=%d num_locks=%d\n",
484	fsp->fsp_name, fsp->fnum, (unsigned int)locktype, num_locks) );
485
486	reply_lockingX_success(blr);
487	return True;
488	} else if (!NT_STATUS_EQUAL(status,NT_STATUS_LOCK_NOT_GRANTED) &&
489	!NT_STATUS_EQUAL(status,NT_STATUS_FILE_LOCK_CONFLICT)) {
490	/*
491	* We have other than a "can't get lock"
492	* error. Free any locks we had and return an error.
493	* Return True so we get dequeued.
494	*/
495
496	blocking_lock_reply_error(blr, status);
497	return True;
498	}
499
500	/*
501	* Still can't get all the locks - keep waiting.
502	*/
503
504	DEBUG(10,("process_lockingX: only got %d locks of %d needed for file %s, fnum = %d. \
505	Waiting....\n",
506	blr->lock_num, num_locks, fsp->fsp_name, fsp->fnum));
507
508	return False;
509	}
510
511	/****************************************************************************
512	Attempt to get the posix lock request from a SMBtrans2 call.
513	Returns True if we want to be removed from the list.
514	*****************************************************************************/
515
516	static bool process_trans2(blocking_lock_record *blr)
517	{
518	struct smb_request *req;
519	char params[2];
520	NTSTATUS status;
521	struct byte_range_lock *br_lck = do_lock(smbd_messaging_context(),
522	blr->fsp,
523	blr->lock_pid,
524	blr->count,
525	blr->offset,
526	blr->lock_type,
527	blr->lock_flav,
528	True,
529	&status,
530	&blr->blocking_pid);
531	TALLOC_FREE(br_lck);
532
533	if (!NT_STATUS_IS_OK(status)) {
534	if (ERROR_WAS_LOCK_DENIED(status)) {
535	/* Still can't get the lock, just keep waiting. */
536	return False;
537	}
538	/*
539	* We have other than a "can't get lock"
540	* error. Send an error and return True so we get dequeued.
541	*/
542	blocking_lock_reply_error(blr, status);
543	return True;
544	}
545
546	/* We finally got the lock, return success. */
547
548	if (!(req = talloc(talloc_tos(), struct smb_request))) {
549	blocking_lock_reply_error(blr, NT_STATUS_NO_MEMORY);
550	return True;
551	}
552
553	init_smb_request(req, (uint8 *)blr->inbuf, 0, blr->encrypted);
554
555	SCVAL(req->inbuf, smb_com, SMBtrans2);
556	SSVAL(params,0,0);
557	/* Fake up max_data_bytes here - we know it fits. */
558	send_trans2_replies(blr->fsp->conn, req, params, 2, NULL, 0, 0xffff);
559	return True;
560	}
561
562
563	/****************************************************************************
564	Process a blocking lock SMB.
565	Returns True if we want to be removed from the list.
566	*****************************************************************************/
567
568	static bool blocking_lock_record_process(blocking_lock_record *blr)
569	{
570	switch(blr->com_type) {
571	case SMBlockingX:
572	return process_lockingX(blr);
573	case SMBtrans2:
574	case SMBtranss2:
575	return process_trans2(blr);
576	default:
577	DEBUG(0,("blocking_lock_record_process: PANIC - unknown type on blocking lock queue - exiting.!\n"));
578	exit_server("PANIC - unknown type on blocking lock queue");
579	}
580	return False; /* Keep compiler happy. */
581	}
582
583	/****************************************************************************
584	Cancel entries by fnum from the blocking lock pending queue.
585	*****************************************************************************/
586
587	void cancel_pending_lock_requests_by_fid(files_struct fsp, struct byte_range_lock br_lck)
588	{
589	blocking_lock_record blr, next = NULL;
590
591	for(blr = blocking_lock_queue; blr; blr = next) {
592	next = blr->next;
593	if(blr->fsp->fnum == fsp->fnum) {
594	unsigned char locktype = 0;
595
596	if (blr->com_type == SMBlockingX) {
597	locktype = CVAL(blr->inbuf,smb_vwv3);
598	}
599
600	if (br_lck) {
601	DEBUG(10,("remove_pending_lock_requests_by_fid - removing request type %d for \
602	file %s fnum = %d\n", blr->com_type, fsp->fsp_name, fsp->fnum ));
603
604	brl_lock_cancel(br_lck,
605	blr->lock_pid,
606	procid_self(),
607	blr->offset,
608	blr->count,
609	blr->lock_flav);
610
611	blocking_lock_cancel(fsp,
612	blr->lock_pid,
613	blr->offset,
614	blr->count,
615	blr->lock_flav,
616	locktype,
617	NT_STATUS_RANGE_NOT_LOCKED);
618	}
619	/* We're closing the file fsp here, so ensure
620	* we don't have a dangling pointer. */
621	blr->fsp = NULL;
622	}
623	}
624	}
625
626	/****************************************************************************
627	Delete entries by mid from the blocking lock pending queue. Always send reply.
628	*****************************************************************************/
629
630	void remove_pending_lock_requests_by_mid(int mid)
631	{
632	blocking_lock_record blr, next = NULL;
633
634	for(blr = blocking_lock_queue; blr; blr = next) {
635	next = blr->next;
636	if(SVAL(blr->inbuf,smb_mid) == mid) {
637	files_struct *fsp = blr->fsp;
638	struct byte_range_lock *br_lck = brl_get_locks(talloc_tos(), fsp);
639
640	if (br_lck) {
641	DEBUG(10,("remove_pending_lock_requests_by_mid - removing request type %d for \
642	file %s fnum = %d\n", blr->com_type, fsp->fsp_name, fsp->fnum ));
643
644	brl_lock_cancel(br_lck,
645	blr->lock_pid,
646	procid_self(),
647	blr->offset,
648	blr->count,
649	blr->lock_flav);
650	TALLOC_FREE(br_lck);
651	}
652
653	blocking_lock_reply_error(blr,NT_STATUS_FILE_LOCK_CONFLICT);
654	DLIST_REMOVE(blocking_lock_queue, blr);
655	free_blocking_lock_record(blr);
656	}
657	}
658	}
659
660	/****************************************************************************
661	Is this mid a blocking lock request on the queue ?
662	*****************************************************************************/
663
664	bool blocking_lock_was_deferred(int mid)
665	{
666	blocking_lock_record blr, next = NULL;
667
668	for(blr = blocking_lock_queue; blr; blr = next) {
669	next = blr->next;
670	if(SVAL(blr->inbuf,smb_mid) == mid) {
671	return True;
672	}
673	}
674	return False;
675	}
676
677	/****************************************************************************
678	Set a flag as an unlock request affects one of our pending locks.
679	*****************************************************************************/
680
681	static void received_unlock_msg(struct messaging_context *msg,
682	void *private_data,
683	uint32_t msg_type,
684	struct server_id server_id,
685	DATA_BLOB *data)
686	{
687	DEBUG(10,("received_unlock_msg\n"));
688	process_blocking_lock_queue();
689	}
690
691	/****************************************************************************
692	Process the blocking lock queue. Note that this is only called as root.
693	*****************************************************************************/
694
695	static void process_blocking_lock_queue(void)
696	{
697	struct timeval tv_curr = timeval_current();
698	blocking_lock_record blr, next = NULL;
699
700	/*
701	* Go through the queue and see if we can get any of the locks.
702	*/
703
704	for (blr = blocking_lock_queue; blr; blr = next) {
705	connection_struct *conn = NULL;
706	uint16 vuid;
707	files_struct *fsp = NULL;
708
709	next = blr->next;
710
711	/*
712	* Ensure we don't have any old chain_fsp values
713	* sitting around....
714	*/
715	chain_size = 0;
716	file_chain_reset();
717	fsp = blr->fsp;
718
719	conn = conn_find(SVAL(blr->inbuf,smb_tid));
720	vuid = (lp_security() == SEC_SHARE) ? UID_FIELD_INVALID :
721	SVAL(blr->inbuf,smb_uid);
722
723	DEBUG(5,("process_blocking_lock_queue: examining pending lock fnum = %d for file %s\n",
724	fsp->fnum, fsp->fsp_name ));
725
726	if(!change_to_user(conn,vuid)) {
727	struct byte_range_lock *br_lck = brl_get_locks(talloc_tos(), fsp);
728
729	/*
730	* Remove the entry and return an error to the client.
731	*/
732
733	if (br_lck) {
734	brl_lock_cancel(br_lck,
735	blr->lock_pid,
736	procid_self(),
737	blr->offset,
738	blr->count,
739	blr->lock_flav);
740	TALLOC_FREE(br_lck);
741	}
742
743	DEBUG(0,("process_blocking_lock_queue: Unable to become user vuid=%d.\n",
744	vuid ));
745	blocking_lock_reply_error(blr,NT_STATUS_ACCESS_DENIED);
746	DLIST_REMOVE(blocking_lock_queue, blr);
747	free_blocking_lock_record(blr);
748	continue;
749	}
750
751	if(!set_current_service(conn,SVAL(blr->inbuf,smb_flg),True)) {
752	struct byte_range_lock *br_lck = brl_get_locks(talloc_tos(), fsp);
753
754	/*
755	* Remove the entry and return an error to the client.
756	*/
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	DEBUG(0,("process_blocking_lock_queue: Unable to become service Error was %s.\n", strerror(errno) ));
769	blocking_lock_reply_error(blr,NT_STATUS_ACCESS_DENIED);
770	DLIST_REMOVE(blocking_lock_queue, blr);
771	free_blocking_lock_record(blr);
772	change_to_root_user();
773	continue;
774	}
775
776	/*
777	* Go through the remaining locks and try and obtain them.
778	* The call returns True if all locks were obtained successfully
779	* and False if we still need to wait.
780	*/
781
782	if(blocking_lock_record_process(blr)) {
783	struct byte_range_lock *br_lck = brl_get_locks(talloc_tos(), fsp);
784
785	if (br_lck) {
786	brl_lock_cancel(br_lck,
787	blr->lock_pid,
788	procid_self(),
789	blr->offset,
790	blr->count,
791	blr->lock_flav);
792	TALLOC_FREE(br_lck);
793	}
794
795	DLIST_REMOVE(blocking_lock_queue, blr);
796	free_blocking_lock_record(blr);
797	change_to_root_user();
798	continue;
799	}
800
801	change_to_root_user();
802
803	/*
804	* We couldn't get the locks for this record on the list.
805	* If the time has expired, return a lock error.
806	*/
807
808	if (!timeval_is_zero(&blr->expire_time) && timeval_compare(&blr->expire_time, &tv_curr) <= 0) {
809	struct byte_range_lock *br_lck = brl_get_locks(talloc_tos(), fsp);
810
811	/*
812	* Lock expired - throw away all previously
813	* obtained locks and return lock error.
814	*/
815
816	if (br_lck) {
817	DEBUG(5,("process_blocking_lock_queue: pending lock fnum = %d for file %s timed out.\n",
818	fsp->fnum, fsp->fsp_name ));
819
820	brl_lock_cancel(br_lck,
821	blr->lock_pid,
822	procid_self(),
823	blr->offset,
824	blr->count,
825	blr->lock_flav);
826	TALLOC_FREE(br_lck);
827	}
828
829	blocking_lock_reply_error(blr,NT_STATUS_FILE_LOCK_CONFLICT);
830	DLIST_REMOVE(blocking_lock_queue, blr);
831	free_blocking_lock_record(blr);
832	}
833	}
834
835	recalc_brl_timeout();
836	}
837
838	/****************************************************************************
839	Handle a cancel message. Lock already moved onto the cancel queue.
840	*****************************************************************************/
841
842	#define MSG_BLOCKING_LOCK_CANCEL_SIZE (sizeof(blocking_lock_record *) + sizeof(NTSTATUS))
843
844	static void process_blocking_lock_cancel_message(struct messaging_context *ctx,
845	void *private_data,
846	uint32_t msg_type,
847	struct server_id server_id,
848	DATA_BLOB *data)
849	{
850	NTSTATUS err;
851	const char msg = (const char )data->data;
852	blocking_lock_record *blr;
853
854	if (data->data == NULL) {
855	smb_panic("process_blocking_lock_cancel_message: null msg");
856	}
857
858	if (data->length != MSG_BLOCKING_LOCK_CANCEL_SIZE) {
859	DEBUG(0, ("process_blocking_lock_cancel_message: "
860	"Got invalid msg len %d\n", (int)data->length));
861	smb_panic("process_blocking_lock_cancel_message: bad msg");
862	}
863
864	memcpy(&blr, msg, sizeof(blr));
865	memcpy(&err, &msg[sizeof(blr)], sizeof(NTSTATUS));
866
867	DEBUG(10,("process_blocking_lock_cancel_message: returning error %s\n",
868	nt_errstr(err) ));
869
870	blocking_lock_reply_error(blr, err);
871	DLIST_REMOVE(blocking_lock_cancelled_queue, blr);
872	free_blocking_lock_record(blr);
873	}
874
875	/****************************************************************************
876	Send ourselves a blocking lock cancelled message. Handled asynchronously above.
877	*****************************************************************************/
878
879	bool blocking_lock_cancel(files_struct *fsp,
880	uint32 lock_pid,
881	SMB_BIG_UINT offset,
882	SMB_BIG_UINT count,
883	enum brl_flavour lock_flav,
884	unsigned char locktype,
885	NTSTATUS err)
886	{
887	static bool initialized;
888	char msg[MSG_BLOCKING_LOCK_CANCEL_SIZE];
889	blocking_lock_record *blr;
890
891	if (!initialized) {
892	/* Register our message. */
893	messaging_register(smbd_messaging_context(), NULL,
894	MSG_SMB_BLOCKING_LOCK_CANCEL,
895	process_blocking_lock_cancel_message);
896
897	initialized = True;
898	}
899
900	for (blr = blocking_lock_queue; blr; blr = blr->next) {
901	if (fsp == blr->fsp &&
902	lock_pid == blr->lock_pid &&
903	offset == blr->offset &&
904	count == blr->count &&
905	lock_flav == blr->lock_flav) {
906	break;
907	}
908	}
909
910	if (!blr) {
911	return False;
912	}
913
914	/* Check the flags are right. */
915	if (blr->com_type == SMBlockingX &&
916	(locktype & LOCKING_ANDX_LARGE_FILES) !=
917	(CVAL(blr->inbuf,smb_vwv3) & LOCKING_ANDX_LARGE_FILES)) {
918	return False;
919	}
920
921	/* Move to cancelled queue. */
922	DLIST_REMOVE(blocking_lock_queue, blr);
923	DLIST_ADD(blocking_lock_cancelled_queue, blr);
924
925	/* Create the message. */
926	memcpy(msg, &blr, sizeof(blr));
927	memcpy(&msg[sizeof(blr)], &err, sizeof(NTSTATUS));
928
929	messaging_send_buf(smbd_messaging_context(), procid_self(),
930	MSG_SMB_BLOCKING_LOCK_CANCEL,
931	(uint8 *)&msg, sizeof(msg));
932
933	return True;
934	}

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