summaryrefslogtreecommitdiff
path: root/source3/locking/locking.c
blob: 28a7fab97d3fd2c0a30fc783adba92df404b77c2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
/* 
   Unix SMB/CIFS implementation.
   Locking functions
   Copyright (C) Andrew Tridgell 1992-2000
   Copyright (C) Jeremy Allison 1992-2006
   Copyright (C) Volker Lendecke 2005
   
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.
   
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
   
   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

   Revision History:

   12 aug 96: Erik.Devriendt@te6.siemens.be
   added support for shared memory implementation of share mode locking

   May 1997. Jeremy Allison (jallison@whistle.com). Modified share mode
   locking to deal with multiple share modes per open file.

   September 1997. Jeremy Allison (jallison@whistle.com). Added oplock
   support.

   rewrtten completely to use new tdb code. Tridge, Dec '99

   Added POSIX locking support. Jeremy Allison (jeremy@valinux.com), Apr. 2000.
   Added Unix Extensions POSIX locking support. Jeremy Allison Mar 2006.
*/

#include "includes.h"

#undef DBGC_CLASS
#define DBGC_CLASS DBGC_LOCKING

/* the locking database handle */
static TDB_CONTEXT *tdb;

/****************************************************************************
 Debugging aids :-).
****************************************************************************/

const char *lock_type_name(enum brl_type lock_type)
{
	switch (lock_type) {
		case READ_LOCK:
			return "READ";
		case WRITE_LOCK:
			return "WRITE";
		case PENDING_READ_LOCK:
			return "PENDING_READ";
		case PENDING_WRITE_LOCK:
			return "PENDING_WRITE";
		default:
			return "other";
	}
}

const char *lock_flav_name(enum brl_flavour lock_flav)
{
	return (lock_flav == WINDOWS_LOCK) ? "WINDOWS_LOCK" : "POSIX_LOCK";
}

/****************************************************************************
 Utility function called to see if a file region is locked.
 Called in the read/write codepath.
****************************************************************************/

BOOL is_locked(files_struct *fsp,
		uint32 smbpid,
		SMB_BIG_UINT count,
		SMB_BIG_UINT offset, 
		enum brl_type lock_type)
{
	int strict_locking = lp_strict_locking(fsp->conn->params);
	enum brl_flavour lock_flav = lp_posix_cifsu_locktype(fsp);
	BOOL ret = True;
	
	if (count == 0) {
		return False;
	}

	if (!lp_locking(fsp->conn->params) || !strict_locking) {
		return False;
	}

	if (strict_locking == Auto) {
		if  (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type) && (lock_type == READ_LOCK || lock_type == WRITE_LOCK)) {
			DEBUG(10,("is_locked: optimisation - exclusive oplock on file %s\n", fsp->fsp_name ));
			ret = False;
		} else if ((fsp->oplock_type == LEVEL_II_OPLOCK) &&
			   (lock_type == READ_LOCK)) {
			DEBUG(10,("is_locked: optimisation - level II oplock on file %s\n", fsp->fsp_name ));
			ret = False;
		} else {
			struct byte_range_lock *br_lck = brl_get_locks_readonly(NULL, fsp);
			if (!br_lck) {
				return False;
			}
			ret = !brl_locktest(br_lck,
					smbpid,
					procid_self(),
					offset,
					count,
					lock_type,
					lock_flav);
			TALLOC_FREE(br_lck);
		}
	} else {
		struct byte_range_lock *br_lck = brl_get_locks_readonly(NULL, fsp);
		if (!br_lck) {
			return False;
		}
		ret = !brl_locktest(br_lck,
				smbpid,
				procid_self(),
				offset,
				count,
				lock_type,
				lock_flav);
		TALLOC_FREE(br_lck);
	}

	DEBUG(10,("is_locked: flavour = %s brl start=%.0f len=%.0f %s for fnum %d file %s\n",
			lock_flav_name(lock_flav),
			(double)offset, (double)count, ret ? "locked" : "unlocked",
			fsp->fnum, fsp->fsp_name ));

	return ret;
}

/****************************************************************************
 Find out if a lock could be granted - return who is blocking us if we can't.
****************************************************************************/

NTSTATUS query_lock(files_struct *fsp,
			uint32 *psmbpid,
			SMB_BIG_UINT *pcount,
			SMB_BIG_UINT *poffset,
			enum brl_type *plock_type,
			enum brl_flavour lock_flav)
{
	struct byte_range_lock *br_lck = NULL;
	NTSTATUS status = NT_STATUS_LOCK_NOT_GRANTED;

	if (!fsp->can_lock) {
		return fsp->is_directory ? NT_STATUS_INVALID_DEVICE_REQUEST : NT_STATUS_INVALID_HANDLE;
	}

	if (!lp_locking(fsp->conn->params)) {
		return NT_STATUS_OK;
	}

	br_lck = brl_get_locks_readonly(NULL, fsp);
	if (!br_lck) {
		return NT_STATUS_NO_MEMORY;
	}

	status = brl_lockquery(br_lck,
			psmbpid,
			procid_self(),
			poffset,
			pcount,
			plock_type,
			lock_flav);

	TALLOC_FREE(br_lck);
	return status;
}

/****************************************************************************
 Utility function called by locking requests.
****************************************************************************/

struct byte_range_lock *do_lock(struct messaging_context *msg_ctx,
			files_struct *fsp,
			uint32 lock_pid,
			SMB_BIG_UINT count,
			SMB_BIG_UINT offset,
			enum brl_type lock_type,
			enum brl_flavour lock_flav,
			BOOL blocking_lock,
			NTSTATUS *perr)
{
	struct byte_range_lock *br_lck = NULL;

	if (!fsp->can_lock) {
		*perr = fsp->is_directory ? NT_STATUS_INVALID_DEVICE_REQUEST : NT_STATUS_INVALID_HANDLE;
		return NULL;
	}

	if (!lp_locking(fsp->conn->params)) {
		*perr = NT_STATUS_OK;
		return NULL;
	}

	/* NOTE! 0 byte long ranges ARE allowed and should be stored  */

	DEBUG(10,("do_lock: lock flavour %s lock type %s start=%.0f len=%.0f requested for fnum %d file %s\n",
		lock_flav_name(lock_flav), lock_type_name(lock_type),
		(double)offset, (double)count, fsp->fnum, fsp->fsp_name ));

	br_lck = brl_get_locks(NULL, fsp);
	if (!br_lck) {
		*perr = NT_STATUS_NO_MEMORY;
		return NULL;
	}

	*perr = brl_lock(msg_ctx,
			br_lck,
			lock_pid,
			procid_self(),
			offset,
			count, 
			lock_type,
			lock_flav,
			blocking_lock);

	/* blocking ie. pending, locks also count here,
	 * as this is an efficiency counter to avoid checking
	 * the lock db. on close. JRA. */

	fsp->current_lock_count++;

	return br_lck;
}

/****************************************************************************
 Utility function called by unlocking requests.
****************************************************************************/

NTSTATUS do_unlock(struct messaging_context *msg_ctx,
			files_struct *fsp,
			uint32 lock_pid,
			SMB_BIG_UINT count,
			SMB_BIG_UINT offset,
			enum brl_flavour lock_flav)
{
	BOOL ok = False;
	struct byte_range_lock *br_lck = NULL;
	
	if (!fsp->can_lock) {
		return fsp->is_directory ? NT_STATUS_INVALID_DEVICE_REQUEST : NT_STATUS_INVALID_HANDLE;
	}
	
	if (!lp_locking(fsp->conn->params)) {
		return NT_STATUS_OK;
	}
	
	DEBUG(10,("do_unlock: unlock start=%.0f len=%.0f requested for fnum %d file %s\n",
		  (double)offset, (double)count, fsp->fnum, fsp->fsp_name ));

	br_lck = brl_get_locks(NULL, fsp);
	if (!br_lck) {
		return NT_STATUS_NO_MEMORY;
	}

	ok = brl_unlock(msg_ctx,
			br_lck,
			lock_pid,
			procid_self(),
			offset,
			count,
			lock_flav);
   
	TALLOC_FREE(br_lck);

	if (!ok) {
		DEBUG(10,("do_unlock: returning ERRlock.\n" ));
		return NT_STATUS_RANGE_NOT_LOCKED;
	}

	SMB_ASSERT(fsp->current_lock_count > 0);
	fsp->current_lock_count--;

	return NT_STATUS_OK;
}

/****************************************************************************
 Cancel any pending blocked locks.
****************************************************************************/

NTSTATUS do_lock_cancel(files_struct *fsp,
			uint32 lock_pid,
			SMB_BIG_UINT count,
			SMB_BIG_UINT offset,
			enum brl_flavour lock_flav)
{
	BOOL ok = False;
	struct byte_range_lock *br_lck = NULL;
	
	if (!fsp->can_lock) {
		return fsp->is_directory ?
			NT_STATUS_INVALID_DEVICE_REQUEST : NT_STATUS_INVALID_HANDLE;
	}
	
	if (!lp_locking(fsp->conn->params)) {
		return NT_STATUS_DOS(ERRDOS, ERRcancelviolation);
	}

	DEBUG(10,("do_lock_cancel: cancel start=%.0f len=%.0f requested for fnum %d file %s\n",
		  (double)offset, (double)count, fsp->fnum, fsp->fsp_name ));

	br_lck = brl_get_locks(NULL, fsp);
	if (!br_lck) {
		return NT_STATUS_NO_MEMORY;
	}

	ok = brl_lock_cancel(br_lck,
			lock_pid,
			procid_self(),
			offset,
			count,
			lock_flav);
   
	TALLOC_FREE(br_lck);

	if (!ok) {
		DEBUG(10,("do_lock_cancel: returning ERRcancelviolation.\n" ));
		return NT_STATUS_DOS(ERRDOS, ERRcancelviolation);
	}

	SMB_ASSERT(fsp->current_lock_count > 0);
	fsp->current_lock_count--;

	return NT_STATUS_OK;
}

/****************************************************************************
 Remove any locks on this fd. Called from file_close().
****************************************************************************/

void locking_close_file(struct messaging_context *msg_ctx,
			files_struct *fsp)
{
	struct byte_range_lock *br_lck;

	if (!lp_locking(fsp->conn->params)) {
		return;
	}

	/* If we have not outstanding locks or pending
	 * locks then we don't need to look in the lock db.
	 */

	if (fsp->current_lock_count == 0) {
		return;
	}

	br_lck = brl_get_locks(NULL,fsp);

	if (br_lck) {
		cancel_pending_lock_requests_by_fid(fsp, br_lck);
		brl_close_fnum(msg_ctx, br_lck);
		TALLOC_FREE(br_lck);
	}
}

/****************************************************************************
 Initialise the locking functions.
****************************************************************************/

static int open_read_only;

BOOL locking_init(int read_only)
{
	brl_init(read_only);

	if (tdb)
		return True;

	tdb = tdb_open_log(lock_path("locking.tdb"), 
			lp_open_files_db_hash_size(),
			TDB_DEFAULT|(read_only?0x0:TDB_CLEAR_IF_FIRST), 
			read_only?O_RDONLY:O_RDWR|O_CREAT,
			0644);

	if (!tdb) {
		DEBUG(0,("ERROR: Failed to initialise locking database\n"));
		return False;
	}

	/* Activate the per-hashchain freelist */
	tdb_set_max_dead(tdb, 5);

	if (!posix_locking_init(read_only))
		return False;

	open_read_only = read_only;

	return True;
}

/*******************************************************************
 Deinitialize the share_mode management.
******************************************************************/

BOOL locking_end(void)
{
	BOOL ret = True;

	brl_shutdown(open_read_only);
	if (tdb) {
		if (tdb_close(tdb) != 0)
			ret = False;
	}

	return ret;
}

/*******************************************************************
 Form a static locking key for a dev/inode pair.
******************************************************************/

/* key and data records in the tdb locking database */
struct locking_key {
	SMB_DEV_T dev;
	SMB_INO_T ino;
};

/*******************************************************************
 Form a static locking key for a dev/inode pair.
******************************************************************/

static TDB_DATA locking_key(SMB_DEV_T dev, SMB_INO_T inode)
{
	static struct locking_key key;
	TDB_DATA kbuf;

	memset(&key, '\0', sizeof(key));
	key.dev = dev;
	key.ino = inode;
	kbuf.dptr = (uint8 *)&key;
	kbuf.dsize = sizeof(key);
	return kbuf;
}

/*******************************************************************
 Print out a share mode.
********************************************************************/

char *share_mode_str(int num, struct share_mode_entry *e)
{
	static pstring share_str;

	slprintf(share_str, sizeof(share_str)-1, "share_mode_entry[%d]: %s "
		 "pid = %s, share_access = 0x%x, private_options = 0x%x, "
		 "access_mask = 0x%x, mid = 0x%x, type= 0x%x, file_id = %lu, "
		 "uid = %u, flags = %u, dev = 0x%x, inode = %.0f",
		 num,
		 e->op_type == UNUSED_SHARE_MODE_ENTRY ? "UNUSED" : "",
		 procid_str_static(&e->pid),
		 e->share_access, e->private_options,
		 e->access_mask, e->op_mid, e->op_type, e->share_file_id,
		 (unsigned int)e->uid, (unsigned int)e->flags,
		 (unsigned int)e->dev, (double)e->inode );

	return share_str;
}

/*******************************************************************
 Print out a share mode table.
********************************************************************/

static void print_share_mode_table(struct locking_data *data)
{
	int num_share_modes = data->u.s.num_share_mode_entries;
	struct share_mode_entry *shares =
		(struct share_mode_entry *)(data + 1);
	int i;

	for (i = 0; i < num_share_modes; i++) {
		struct share_mode_entry entry;

		memcpy(&entry, &shares[i], sizeof(struct share_mode_entry));
		DEBUG(10,("print_share_mode_table: %s\n",
			  share_mode_str(i, &entry)));
	}
}

/*******************************************************************
 Get all share mode entries for a dev/inode pair.
********************************************************************/

static BOOL parse_share_modes(TDB_DATA dbuf, struct share_mode_lock *lck)
{
	struct locking_data *data;
	int i;

	if (dbuf.dsize < sizeof(struct locking_data)) {
		smb_panic("PANIC: parse_share_modes: buffer too short.\n");
	}

	data = (struct locking_data *)dbuf.dptr;

	lck->delete_on_close = data->u.s.delete_on_close;
	lck->num_share_modes = data->u.s.num_share_mode_entries;

	DEBUG(10, ("parse_share_modes: delete_on_close: %d, "
		   "num_share_modes: %d\n",
		lck->delete_on_close,
		lck->num_share_modes));

	if ((lck->num_share_modes < 0) || (lck->num_share_modes > 1000000)) {
		DEBUG(0, ("invalid number of share modes: %d\n",
			  lck->num_share_modes));
		smb_panic("PANIC: invalid number of share modes");
	}

	lck->share_modes = NULL;
	
	if (lck->num_share_modes != 0) {

		if (dbuf.dsize < (sizeof(struct locking_data) +
				  (lck->num_share_modes *
				   sizeof(struct share_mode_entry)))) {
			smb_panic("PANIC: parse_share_modes: buffer too short.\n");
		}
				  
		lck->share_modes = (struct share_mode_entry *)
			TALLOC_MEMDUP(lck, dbuf.dptr+sizeof(*data),
				      lck->num_share_modes *
				      sizeof(struct share_mode_entry));

		if (lck->share_modes == NULL) {
			smb_panic("talloc failed\n");
		}
	}

	/* Get any delete token. */
	if (data->u.s.delete_token_size) {
		uint8 *p = dbuf.dptr + sizeof(*data) +
				(lck->num_share_modes *
				sizeof(struct share_mode_entry));

		if ((data->u.s.delete_token_size < sizeof(uid_t) + sizeof(gid_t)) ||
				((data->u.s.delete_token_size - sizeof(uid_t)) % sizeof(gid_t)) != 0) {
			DEBUG(0, ("parse_share_modes: invalid token size %d\n",
				data->u.s.delete_token_size));
			smb_panic("parse_share_modes: invalid token size\n");
		}

		lck->delete_token = TALLOC_P(lck, UNIX_USER_TOKEN);
		if (!lck->delete_token) {
			smb_panic("talloc failed\n");
		}

		/* Copy out the uid and gid. */
		memcpy(&lck->delete_token->uid, p, sizeof(uid_t));
		p += sizeof(uid_t);
		memcpy(&lck->delete_token->gid, p, sizeof(gid_t));
		p += sizeof(gid_t);

		/* Any supplementary groups ? */
		lck->delete_token->ngroups = (data->u.s.delete_token_size > (sizeof(uid_t) + sizeof(gid_t))) ?
					((data->u.s.delete_token_size -
						(sizeof(uid_t) + sizeof(gid_t)))/sizeof(gid_t)) : 0;

		if (lck->delete_token->ngroups) {
			/* Make this a talloc child of lck->delete_token. */
			lck->delete_token->groups = TALLOC_ARRAY(lck->delete_token, gid_t,
							lck->delete_token->ngroups);
			if (!lck->delete_token) {
				smb_panic("talloc failed\n");
			}

			for (i = 0; i < lck->delete_token->ngroups; i++) {
				memcpy(&lck->delete_token->groups[i], p, sizeof(gid_t));
				p += sizeof(gid_t);
			}
		}

	} else {
		lck->delete_token = NULL;
	}

	/* Save off the associated service path and filename. */
	lck->servicepath = talloc_strdup(lck, (const char *)dbuf.dptr + sizeof(*data) +
					(lck->num_share_modes *
					sizeof(struct share_mode_entry)) +
					data->u.s.delete_token_size );
	if (lck->servicepath == NULL) {
		smb_panic("talloc_strdup failed\n");
	}

	lck->filename = talloc_strdup(lck, (const char *)dbuf.dptr + sizeof(*data) +
					(lck->num_share_modes *
					sizeof(struct share_mode_entry)) +
					data->u.s.delete_token_size +
					strlen(lck->servicepath) + 1 );
	if (lck->filename == NULL) {
		smb_panic("talloc_strdup failed\n");
	}

	/*
	 * Ensure that each entry has a real process attached.
	 */

	for (i = 0; i < lck->num_share_modes; i++) {
		struct share_mode_entry *entry_p = &lck->share_modes[i];
		DEBUG(10,("parse_share_modes: %s\n",
			  share_mode_str(i, entry_p) ));
		if (!process_exists(entry_p->pid)) {
			DEBUG(10,("parse_share_modes: deleted %s\n",
				  share_mode_str(i, entry_p) ));
			entry_p->op_type = UNUSED_SHARE_MODE_ENTRY;
			lck->modified = True;
		}
	}

	return True;
}

static TDB_DATA unparse_share_modes(struct share_mode_lock *lck)
{
	TDB_DATA result;
	int num_valid = 0;
	int i;
	struct locking_data *data;
	ssize_t offset;
	ssize_t sp_len;
	uint32 delete_token_size;

	result.dptr = NULL;
	result.dsize = 0;

	for (i=0; i<lck->num_share_modes; i++) {
		if (!is_unused_share_mode_entry(&lck->share_modes[i])) {
			num_valid += 1;
		}
	}

	if (num_valid == 0) {
		return result;
	}

	sp_len = strlen(lck->servicepath);
	delete_token_size = (lck->delete_token ?
			(sizeof(uid_t) + sizeof(gid_t) + (lck->delete_token->ngroups*sizeof(gid_t))) : 0);

	result.dsize = sizeof(*data) +
		lck->num_share_modes * sizeof(struct share_mode_entry) +
		delete_token_size +
		sp_len + 1 +
		strlen(lck->filename) + 1;
	result.dptr = TALLOC_ARRAY(lck, uint8, result.dsize);

	if (result.dptr == NULL) {
		smb_panic("talloc failed\n");
	}

	data = (struct locking_data *)result.dptr;
	ZERO_STRUCTP(data);
	data->u.s.num_share_mode_entries = lck->num_share_modes;
	data->u.s.delete_on_close = lck->delete_on_close;
	data->u.s.delete_token_size = delete_token_size;
	DEBUG(10, ("unparse_share_modes: del: %d, tok = %u, num: %d\n",
		data->u.s.delete_on_close,
		(unsigned int)data->u.s.delete_token_size,
		data->u.s.num_share_mode_entries));
	memcpy(result.dptr + sizeof(*data), lck->share_modes,
	       sizeof(struct share_mode_entry)*lck->num_share_modes);
	offset = sizeof(*data) +
		sizeof(struct share_mode_entry)*lck->num_share_modes;

	/* Store any delete on close token. */
	if (lck->delete_token) {
		uint8 *p = result.dptr + offset;

		memcpy(p, &lck->delete_token->uid, sizeof(uid_t));
		p += sizeof(uid_t);

		memcpy(p, &lck->delete_token->gid, sizeof(gid_t));
		p += sizeof(gid_t);

		for (i = 0; i < lck->delete_token->ngroups; i++) {
			memcpy(p, &lck->delete_token->groups[i], sizeof(gid_t));
			p += sizeof(gid_t);
		}
		offset = p - result.dptr;
	}

	safe_strcpy((char *)result.dptr + offset, lck->servicepath,
		    result.dsize - offset - 1);
	offset += sp_len + 1;
	safe_strcpy((char *)result.dptr + offset, lck->filename,
		    result.dsize - offset - 1);

	if (DEBUGLEVEL >= 10) {
		print_share_mode_table(data);
	}

	return result;
}

static int share_mode_lock_destructor(struct share_mode_lock *lck)
{
	TDB_DATA key = locking_key(lck->dev, lck->ino);
	TDB_DATA data;

	if (!lck->modified) {
		goto done;
	}

	data = unparse_share_modes(lck);

	if (data.dptr == NULL) {
		if (!lck->fresh) {
			/* There has been an entry before, delete it */
			if (tdb_delete(tdb, key) == -1) {
				smb_panic("Could not delete share entry\n");
			}
		}
		goto done;
	}

	if (tdb_store(tdb, key, data, TDB_REPLACE) == -1) {
		smb_panic("Could not store share mode entry\n");
	}

 done:
	tdb_chainunlock(tdb, key);

	return 0;
}

struct share_mode_lock *get_share_mode_lock(TALLOC_CTX *mem_ctx,
						SMB_DEV_T dev, SMB_INO_T ino,
						const char *servicepath,
						const char *fname)
{
	struct share_mode_lock *lck;
	TDB_DATA key = locking_key(dev, ino);
	TDB_DATA data;

	lck = TALLOC_P(mem_ctx, struct share_mode_lock);
	if (lck == NULL) {
		DEBUG(0, ("talloc failed\n"));
		return NULL;
	}

	/* Ensure we set every field here as the destructor must be
	   valid even if parse_share_modes fails. */

	lck->servicepath = NULL;
	lck->filename = NULL;
	lck->dev = dev;
	lck->ino = ino;
	lck->num_share_modes = 0;
	lck->share_modes = NULL;
	lck->delete_token = NULL;
	lck->delete_on_close = False;
	lck->fresh = False;
	lck->modified = False;

	if (tdb_chainlock(tdb, key) != 0) {
		DEBUG(3, ("Could not lock share entry\n"));
		TALLOC_FREE(lck);
		return NULL;
	}

	/* We must set the destructor immediately after the chainlock
	   ensure the lock is cleaned up on any of the error return
	   paths below. */

	talloc_set_destructor(lck, share_mode_lock_destructor);

	data = tdb_fetch(tdb, key);
	lck->fresh = (data.dptr == NULL);

	if (lck->fresh) {

		if (fname == NULL || servicepath == NULL) {
			TALLOC_FREE(lck);
			return NULL;
		}
		lck->filename = talloc_strdup(lck, fname);
		lck->servicepath = talloc_strdup(lck, servicepath);
		if (lck->filename == NULL || lck->servicepath == NULL) {
			DEBUG(0, ("talloc failed\n"));
			TALLOC_FREE(lck);
			return NULL;
		}
	} else {
		if (!parse_share_modes(data, lck)) {
			DEBUG(0, ("Could not parse share modes\n"));
			TALLOC_FREE(lck);
			SAFE_FREE(data.dptr);
			return NULL;
		}
	}

	SAFE_FREE(data.dptr);

	return lck;
}

/*******************************************************************
 Sets the service name and filename for rename.
 At this point we emit "file renamed" messages to all
 process id's that have this file open.
 Based on an initial code idea from SATOH Fumiyasu <fumiya@samba.gr.jp>
********************************************************************/

BOOL rename_share_filename(struct messaging_context *msg_ctx,
			struct share_mode_lock *lck,
			const char *servicepath,
			const char *newname)
{
	size_t sp_len;
	size_t fn_len;
	size_t msg_len;
	char *frm = NULL;
	int i;
	DATA_BLOB msg;

	if (!lck) {
		return False;
	}

	DEBUG(10, ("rename_share_filename: servicepath %s newname %s\n",
		servicepath, newname));

	/*
	 * rename_internal_fsp() and rename_internals() add './' to
	 * head of newname if newname does not contain a '/'.
	 */
	while (newname[0] && newname[1] && newname[0] == '.' && newname[1] == '/') {
		newname += 2;
	}

	lck->servicepath = talloc_strdup(lck, servicepath);
	lck->filename = talloc_strdup(lck, newname);
	if (lck->filename == NULL || lck->servicepath == NULL) {
		DEBUG(0, ("rename_share_filename: talloc failed\n"));
		return False;
	}
	lck->modified = True;

	sp_len = strlen(lck->servicepath);
	fn_len = strlen(lck->filename);

	msg_len = MSG_FILE_RENAMED_MIN_SIZE + sp_len + 1 + fn_len + 1;

	/* Set up the name changed message. */
	frm = TALLOC_ARRAY(lck, char, msg_len);
	if (!frm) {
		return False;
	}

	SDEV_T_VAL(frm,0,lck->dev);
	SINO_T_VAL(frm,8,lck->ino);

	DEBUG(10,("rename_share_filename: msg_len = %u\n", (unsigned int)msg_len ));

	safe_strcpy(&frm[16], lck->servicepath, sp_len);
	safe_strcpy(&frm[16 + sp_len + 1], lck->filename, fn_len);

	msg = data_blob_const(frm, msg_len);

	/* Send the messages. */
	for (i=0; i<lck->num_share_modes; i++) {
		struct share_mode_entry *se = &lck->share_modes[i];
		if (!is_valid_share_mode_entry(se)) {
			continue;
		}
		/* But not to ourselves... */
		if (procid_is_me(&se->pid)) {
			continue;
		}

		DEBUG(10,("rename_share_filename: sending rename message to pid %s "
			"dev %x, inode  %.0f sharepath %s newname %s\n",
			procid_str_static(&se->pid),
			(unsigned int)lck->dev, (double)lck->ino,
			lck->servicepath, lck->filename ));

		messaging_send(msg_ctx, se->pid, MSG_SMB_FILE_RENAME, &msg);
	}

	return True;
}

static int pull_delete_on_close_flag(TDB_DATA key, TDB_DATA dbuf,
				     void *private_data)
{
	BOOL *result = (BOOL *)private_data;
	struct locking_data *data;

	if (dbuf.dsize < sizeof(struct locking_data)) {
		smb_panic("PANIC: parse_share_modes: buffer too short.\n");
	}

	data = (struct locking_data *)dbuf.dptr;

	*result = data->u.s.delete_on_close;
	return 0;
}

BOOL get_delete_on_close_flag(SMB_DEV_T dev, SMB_INO_T inode)
{
	TDB_DATA key = locking_key(dev, inode);
	BOOL result = False;

	tdb_parse_record(tdb, key, pull_delete_on_close_flag,
			 (void *)&result);
	return result;
}

BOOL is_valid_share_mode_entry(const struct share_mode_entry *e)
{
	int num_props = 0;

	num_props += ((e->op_type == NO_OPLOCK) ? 1 : 0);
	num_props += (EXCLUSIVE_OPLOCK_TYPE(e->op_type) ? 1 : 0);
	num_props += (LEVEL_II_OPLOCK_TYPE(e->op_type) ? 1 : 0);

	SMB_ASSERT(num_props <= 1);
	return (num_props != 0);
}

BOOL is_deferred_open_entry(const struct share_mode_entry *e)
{
	return (e->op_type == DEFERRED_OPEN_ENTRY);
}

BOOL is_unused_share_mode_entry(const struct share_mode_entry *e)
{
	return (e->op_type == UNUSED_SHARE_MODE_ENTRY);
}

/*******************************************************************
 Fill a share mode entry.
********************************************************************/

static void fill_share_mode_entry(struct share_mode_entry *e,
				  files_struct *fsp,
				  uid_t uid, uint16 mid, uint16 op_type)
{
	ZERO_STRUCTP(e);
	e->pid = procid_self();
	e->share_access = fsp->share_access;
	e->private_options = fsp->fh->private_options;
	e->access_mask = fsp->access_mask;
	e->op_mid = mid;
	e->op_type = op_type;
	e->time.tv_sec = fsp->open_time.tv_sec;
	e->time.tv_usec = fsp->open_time.tv_usec;
	e->dev = fsp->dev;
	e->inode = fsp->inode;
	e->share_file_id = fsp->fh->file_id;
	e->uid = (uint32)uid;
	e->flags = fsp->posix_open ? SHARE_MODE_FLAG_POSIX_OPEN : 0;
}

static void fill_deferred_open_entry(struct share_mode_entry *e,
				     const struct timeval request_time,
				     SMB_DEV_T dev, SMB_INO_T ino, uint16 mid)
{
	ZERO_STRUCTP(e);
	e->pid = procid_self();
	e->op_mid = mid;
	e->op_type = DEFERRED_OPEN_ENTRY;
	e->time.tv_sec = request_time.tv_sec;
	e->time.tv_usec = request_time.tv_usec;
	e->dev = dev;
	e->inode = ino;
	e->uid = (uint32)-1;
	e->flags = 0;
}

static void add_share_mode_entry(struct share_mode_lock *lck,
				 const struct share_mode_entry *entry)
{
	int i;

	for (i=0; i<lck->num_share_modes; i++) {
		struct share_mode_entry *e = &lck->share_modes[i];
		if (is_unused_share_mode_entry(e)) {
			*e = *entry;
			break;
		}
	}

	if (i == lck->num_share_modes) {
		/* No unused entry found */
		ADD_TO_ARRAY(lck, struct share_mode_entry, *entry,
			     &lck->share_modes, &lck->num_share_modes);
	}
	lck->modified = True;
}

void set_share_mode(struct share_mode_lock *lck, files_struct *fsp,
			uid_t uid, uint16 mid, uint16 op_type)
{
	struct share_mode_entry entry;
	fill_share_mode_entry(&entry, fsp, uid, mid, op_type);
	add_share_mode_entry(lck, &entry);
}

void add_deferred_open(struct share_mode_lock *lck, uint16 mid,
		       struct timeval request_time,
		       SMB_DEV_T dev, SMB_INO_T ino)
{
	struct share_mode_entry entry;
	fill_deferred_open_entry(&entry, request_time, dev, ino, mid);
	add_share_mode_entry(lck, &entry);
}

/*******************************************************************
 Check if two share mode entries are identical, ignoring oplock 
 and mid info and desired_access. (Removed paranoia test - it's
 not automatically a logic error if they are identical. JRA.)
********************************************************************/

static BOOL share_modes_identical(struct share_mode_entry *e1,
				  struct share_mode_entry *e2)
{
	/* We used to check for e1->share_access == e2->share_access here
	   as well as the other fields but 2 different DOS or FCB opens
	   sharing the same share mode entry may validly differ in
	   fsp->share_access field. */

	return (procid_equal(&e1->pid, &e2->pid) &&
		e1->dev == e2->dev &&
		e1->inode == e2->inode &&
		e1->share_file_id == e2->share_file_id );
}

static BOOL deferred_open_identical(struct share_mode_entry *e1,
				    struct share_mode_entry *e2)
{
	return (procid_equal(&e1->pid, &e2->pid) &&
		(e1->op_mid == e2->op_mid) &&
		(e1->dev == e2->dev) &&
		(e1->inode == e2->inode));
}

static struct share_mode_entry *find_share_mode_entry(struct share_mode_lock *lck,
						      struct share_mode_entry *entry)
{
	int i;

	for (i=0; i<lck->num_share_modes; i++) {
		struct share_mode_entry *e = &lck->share_modes[i];
		if (is_valid_share_mode_entry(entry) &&
		    is_valid_share_mode_entry(e) &&
		    share_modes_identical(e, entry)) {
			return e;
		}
		if (is_deferred_open_entry(entry) &&
		    is_deferred_open_entry(e) &&
		    deferred_open_identical(e, entry)) {
			return e;
		}
	}
	return NULL;
}

/*******************************************************************
 Del the share mode of a file for this process. Return the number of
 entries left.
********************************************************************/

BOOL del_share_mode(struct share_mode_lock *lck, files_struct *fsp)
{
	struct share_mode_entry entry, *e;

	/* Don't care about the pid owner being correct here - just a search. */
	fill_share_mode_entry(&entry, fsp, (uid_t)-1, 0, NO_OPLOCK);

	e = find_share_mode_entry(lck, &entry);
	if (e == NULL) {
		return False;
	}

	e->op_type = UNUSED_SHARE_MODE_ENTRY;
	lck->modified = True;
	return True;
}

void del_deferred_open_entry(struct share_mode_lock *lck, uint16 mid)
{
	struct share_mode_entry entry, *e;

	fill_deferred_open_entry(&entry, timeval_zero(),
				 lck->dev, lck->ino, mid);

	e = find_share_mode_entry(lck, &entry);
	if (e == NULL) {
		return;
	}

	e->op_type = UNUSED_SHARE_MODE_ENTRY;
	lck->modified = True;
}

/*******************************************************************
 Remove an oplock mid and mode entry from a share mode.
********************************************************************/

BOOL remove_share_oplock(struct share_mode_lock *lck, files_struct *fsp)
{
	struct share_mode_entry entry, *e;

	/* Don't care about the pid owner being correct here - just a search. */
	fill_share_mode_entry(&entry, fsp, (uid_t)-1, 0, NO_OPLOCK);

	e = find_share_mode_entry(lck, &entry);
	if (e == NULL) {
		return False;
	}

	e->op_mid = 0;
	e->op_type = NO_OPLOCK;
	lck->modified = True;
	return True;
}

/*******************************************************************
 Downgrade a oplock type from exclusive to level II.
********************************************************************/

BOOL downgrade_share_oplock(struct share_mode_lock *lck, files_struct *fsp)
{
	struct share_mode_entry entry, *e;

	/* Don't care about the pid owner being correct here - just a search. */
	fill_share_mode_entry(&entry, fsp, (uid_t)-1, 0, NO_OPLOCK);

	e = find_share_mode_entry(lck, &entry);
	if (e == NULL) {
		return False;
	}

	e->op_type = LEVEL_II_OPLOCK;
	lck->modified = True;
	return True;
}

/****************************************************************************
 Deal with the internal needs of setting the delete on close flag. Note that
 as the tdb locking is recursive, it is safe to call this from within 
 open_file_ntcreate. JRA.
****************************************************************************/

NTSTATUS can_set_delete_on_close(files_struct *fsp, BOOL delete_on_close,
				 uint32 dosmode)
{
	if (!delete_on_close) {
		return NT_STATUS_OK;
	}

	/*
	 * Only allow delete on close for writable files.
	 */

	if ((dosmode & aRONLY) &&
	    !lp_delete_readonly(SNUM(fsp->conn))) {
		DEBUG(10,("can_set_delete_on_close: file %s delete on close "
			  "flag set but file attribute is readonly.\n",
			  fsp->fsp_name ));
		return NT_STATUS_CANNOT_DELETE;
	}

	/*
	 * Only allow delete on close for writable shares.
	 */

	if (!CAN_WRITE(fsp->conn)) {
		DEBUG(10,("can_set_delete_on_close: file %s delete on "
			  "close flag set but write access denied on share.\n",
			  fsp->fsp_name ));
		return NT_STATUS_ACCESS_DENIED;
	}

	/*
	 * Only allow delete on close for files/directories opened with delete
	 * intent.
	 */

	if (!(fsp->access_mask & DELETE_ACCESS)) {
		DEBUG(10,("can_set_delete_on_close: file %s delete on "
			  "close flag set but delete access denied.\n",
			  fsp->fsp_name ));
		return NT_STATUS_ACCESS_DENIED;
	}

	/* Don't allow delete on close for non-empty directories. */
	if (fsp->is_directory) {
		return can_delete_directory(fsp->conn, fsp->fsp_name);
	}

	return NT_STATUS_OK;
}

/*************************************************************************
 Return a talloced copy of a UNIX_USER_TOKEN. NULL on fail.
 (Should this be in locking.c.... ?).
*************************************************************************/

static UNIX_USER_TOKEN *copy_unix_token(TALLOC_CTX *ctx, UNIX_USER_TOKEN *tok)
{
	UNIX_USER_TOKEN *cpy;

	if (tok == NULL) {
		return NULL;
	}

	cpy = TALLOC_P(ctx, UNIX_USER_TOKEN);
	if (!cpy) {
		return NULL;
	}

	cpy->uid = tok->uid;
	cpy->gid = tok->gid;
	cpy->ngroups = tok->ngroups;
	if (tok->ngroups) {
		/* Make this a talloc child of cpy. */
		cpy->groups = TALLOC_ARRAY(cpy, gid_t, tok->ngroups);
		if (!cpy->groups) {
			return NULL;
		}
		memcpy(cpy->groups, tok->groups, tok->ngroups * sizeof(gid_t));
	}
	return cpy;
}

/****************************************************************************
 Replace the delete on close token.
****************************************************************************/

void set_delete_on_close_token(struct share_mode_lock *lck, UNIX_USER_TOKEN *tok)
{
	/* Ensure there's no token. */
	if (lck->delete_token) {
		TALLOC_FREE(lck->delete_token); /* Also deletes groups... */
		lck->delete_token = NULL;
	}

	/* Copy the new token (can be NULL). */
	lck->delete_token = copy_unix_token(lck, tok);
	lck->modified = True;
}

/****************************************************************************
 Sets the delete on close flag over all share modes on this file.
 Modify the share mode entry for all files open
 on this device and inode to tell other smbds we have
 changed the delete on close flag. This will be noticed
 in the close code, the last closer will delete the file
 if flag is set.
 This makes a copy of any UNIX_USER_TOKEN into the
 lck entry. This function is used when the lock is already granted.
****************************************************************************/

void set_delete_on_close_lck(struct share_mode_lock *lck, BOOL delete_on_close, UNIX_USER_TOKEN *tok)
{
	if (lck->delete_on_close != delete_on_close) {
		set_delete_on_close_token(lck, tok);
		lck->delete_on_close = delete_on_close;
		if (delete_on_close) {
			SMB_ASSERT(lck->delete_token != NULL);
		}
		lck->modified = True;
	}
}

BOOL set_delete_on_close(files_struct *fsp, BOOL delete_on_close, UNIX_USER_TOKEN *tok)
{
	struct share_mode_lock *lck;
	
	DEBUG(10,("set_delete_on_close: %s delete on close flag for "
		  "fnum = %d, file %s\n",
		  delete_on_close ? "Adding" : "Removing", fsp->fnum,
		  fsp->fsp_name ));

	if (fsp->is_stat) {
		return True;
	}

	lck = get_share_mode_lock(NULL, fsp->dev, fsp->inode, NULL, NULL);
	if (lck == NULL) {
		return False;
	}

	set_delete_on_close_lck(lck, delete_on_close, tok);

	if (fsp->is_directory) {
		send_stat_cache_delete_message(fsp->fsp_name);
	}

	TALLOC_FREE(lck);
	return True;
}

struct forall_state {
	void (*fn)(const struct share_mode_entry *entry,
		   const char *sharepath,
		   const char *fname,
		   void *private_data);
	void *private_data;
};

static int traverse_fn(TDB_CONTEXT *the_tdb, TDB_DATA kbuf, TDB_DATA dbuf, 
                       void *_state)
{
	struct forall_state *state = (struct forall_state *)_state;
	struct locking_data *data;
	struct share_mode_entry *shares;
	const char *sharepath;
	const char *fname;
	int i;

	/* Ensure this is a locking_key record. */
	if (kbuf.dsize != sizeof(struct locking_key))
		return 0;

	data = (struct locking_data *)dbuf.dptr;
	shares = (struct share_mode_entry *)(dbuf.dptr + sizeof(*data));
	sharepath = (const char *)dbuf.dptr + sizeof(*data) +
		data->u.s.num_share_mode_entries*sizeof(*shares) +
		data->u.s.delete_token_size;
	fname = (const char *)dbuf.dptr + sizeof(*data) +
		data->u.s.num_share_mode_entries*sizeof(*shares) +
		data->u.s.delete_token_size +
		strlen(sharepath) + 1;

	for (i=0;i<data->u.s.num_share_mode_entries;i++) {
		state->fn(&shares[i], sharepath, fname,
			  state->private_data);
	}
	return 0;
}

/*******************************************************************
 Call the specified function on each entry under management by the
 share mode system.
********************************************************************/

int share_mode_forall(void (*fn)(const struct share_mode_entry *, const char *,
				 const char *, void *),
		      void *private_data)
{
	struct forall_state state;

	if (tdb == NULL)
		return 0;

	state.fn = fn;
	state.private_data = private_data;

	return tdb_traverse(tdb, traverse_fn, (void *)&state);
}