summaryrefslogtreecommitdiff
path: root/source3/modules/vfs_streams_depot.c
blob: da11ba432369dd5e34fd8981f2abf73708e03765 (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
/*
 * Store streams in a separate subdirectory
 *
 * Copyright (C) Volker Lendecke, 2007
 *
 * 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 3 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, see <http://www.gnu.org/licenses/>.
 */

#include "includes.h"
#include "smbd/smbd.h"
#include "system/filesys.h"

#undef DBGC_CLASS
#define DBGC_CLASS DBGC_VFS

/*
 * Excerpt from a mail from tridge:
 *
 * Volker, what I'm thinking of is this:
 * /mount-point/.streams/XX/YY/aaaa.bbbb/namedstream1
 * /mount-point/.streams/XX/YY/aaaa.bbbb/namedstream2
 *
 * where XX/YY is a 2 level hash based on the fsid/inode. "aaaa.bbbb"
 * is the fsid/inode. "namedstreamX" is a file named after the stream
 * name.
 */

static uint32_t hash_fn(DATA_BLOB key)
{
	uint32_t value;	/* Used to compute the hash value.  */
	uint32_t i;	/* Used to cycle through random values. */

	/* Set the initial value from the key size. */
	for (value = 0x238F13AF * key.length, i=0; i < key.length; i++)
		value = (value + (key.data[i] << (i*5 % 24)));

	return (1103515243 * value + 12345);
}

/*
 * With the hashing scheme based on the inode we need to protect against
 * streams showing up on files with re-used inodes. This can happen if we
 * create a stream directory from within Samba, and a local process or NFS
 * client deletes the file without deleting the streams directory. When the
 * inode is re-used and the stream directory is still around, the streams in
 * there would be show up as belonging to the new file.
 *
 * There are several workarounds for this, probably the easiest one is on
 * systems which have a true birthtime stat element: When the file has a later
 * birthtime than the streams directory, then we have to recreate the
 * directory.
 *
 * The other workaround is to somehow mark the file as generated by Samba with
 * something that a NFS client would not do. The closest one is a special
 * xattr value being set. On systems which do not support xattrs, it might be
 * an option to put in a special ACL entry for a non-existing group.
 */

static bool file_is_valid(vfs_handle_struct *handle, const char *path)
{
	char buf;

	DEBUG(10, ("file_is_valid (%s) called\n", path));

	if (SMB_VFS_GETXATTR(handle->conn, path, SAMBA_XATTR_MARKER,
				  &buf, sizeof(buf)) != sizeof(buf)) {
		DEBUG(10, ("GETXATTR failed: %s\n", strerror(errno)));
		return false;
	}

	if (buf != '1') {
		DEBUG(10, ("got wrong buffer content: '%c'\n", buf));
		return false;
	}

	return true;
}

static bool mark_file_valid(vfs_handle_struct *handle, const char *path)
{
	char buf = '1';
	int ret;

	DEBUG(10, ("marking file %s as valid\n", path));

	ret = SMB_VFS_SETXATTR(handle->conn, path, SAMBA_XATTR_MARKER,
				    &buf, sizeof(buf), 0);

	if (ret == -1) {
		DEBUG(10, ("SETXATTR failed: %s\n", strerror(errno)));
		return false;
	}

	return true;
}

/**
 * Given an smb_filename, determine the stream directory using the file's
 * base_name.
 */
static char *stream_dir(vfs_handle_struct *handle,
			const struct smb_filename *smb_fname,
			const SMB_STRUCT_STAT *base_sbuf, bool create_it)
{
	uint32_t hash;
	struct smb_filename *smb_fname_hash = NULL;
	char *result = NULL;
	SMB_STRUCT_STAT base_sbuf_tmp;
	uint8_t first, second;
	char *tmp;
	char *id_hex;
	struct file_id id;
	uint8 id_buf[16];
	bool check_valid;
	const char *rootdir;

	check_valid = lp_parm_bool(SNUM(handle->conn),
		      "streams_depot", "check_valid", true);

	tmp = talloc_asprintf(talloc_tos(), "%s/.streams", handle->conn->cwd);

	if (tmp == NULL) {
		errno = ENOMEM;
		goto fail;
	}

	rootdir = lp_parm_const_string(
		SNUM(handle->conn), "streams_depot", "directory",
		tmp);

	/* Stat the base file if it hasn't already been done. */
	if (base_sbuf == NULL) {
		struct smb_filename *smb_fname_base;

		smb_fname_base = synthetic_smb_fname(
			talloc_tos(), smb_fname->base_name, NULL, NULL);
		if (smb_fname_base == NULL) {
			errno = ENOMEM;
			goto fail;
		}
		if (SMB_VFS_NEXT_STAT(handle, smb_fname_base) == -1) {
			TALLOC_FREE(smb_fname_base);
			goto fail;
		}
		base_sbuf_tmp = smb_fname_base->st;
		TALLOC_FREE(smb_fname_base);
	} else {
		base_sbuf_tmp = *base_sbuf;
	}

	id = SMB_VFS_FILE_ID_CREATE(handle->conn, &base_sbuf_tmp);

	push_file_id_16((char *)id_buf, &id);

	hash = hash_fn(data_blob_const(id_buf, sizeof(id_buf)));

	first = hash & 0xff;
	second = (hash >> 8) & 0xff;

	id_hex = hex_encode_talloc(talloc_tos(), id_buf, sizeof(id_buf));

	if (id_hex == NULL) {
		errno = ENOMEM;
		goto fail;
	}

	result = talloc_asprintf(talloc_tos(), "%s/%2.2X/%2.2X/%s", rootdir,
				 first, second, id_hex);

	TALLOC_FREE(id_hex);

	if (result == NULL) {
		errno = ENOMEM;
		return NULL;
	}

	smb_fname_hash = synthetic_smb_fname(talloc_tos(), result, NULL, NULL);
	if (smb_fname_hash == NULL) {
		errno = ENOMEM;
		goto fail;
	}

	if (SMB_VFS_NEXT_STAT(handle, smb_fname_hash) == 0) {
		struct smb_filename *smb_fname_new = NULL;
		char *newname;
		bool delete_lost;

		if (!S_ISDIR(smb_fname_hash->st.st_ex_mode)) {
			errno = EINVAL;
			goto fail;
		}

		if (!check_valid ||
		    file_is_valid(handle, smb_fname->base_name)) {
			return result;
		}

		/*
		 * Someone has recreated a file under an existing inode
		 * without deleting the streams directory.
		 * Move it away or remove if streams_depot:delete_lost is set.
		 */

	again:
		delete_lost = lp_parm_bool(SNUM(handle->conn), "streams_depot",
					   "delete_lost", false);

		if (delete_lost) {
			DEBUG(3, ("Someone has recreated a file under an "
			      "existing inode. Removing: %s\n",
			      smb_fname_hash->base_name));
			recursive_rmdir(talloc_tos(), handle->conn,
					smb_fname_hash);
			SMB_VFS_NEXT_RMDIR(handle, smb_fname_hash->base_name);
		} else {
			newname = talloc_asprintf(talloc_tos(), "lost-%lu",
						  random());
			DEBUG(3, ("Someone has recreated a file under an "
			      "existing inode. Renaming: %s to: %s\n",
			      smb_fname_hash->base_name,
			      newname));
			if (newname == NULL) {
				errno = ENOMEM;
				goto fail;
			}

			smb_fname_new = synthetic_smb_fname(
				talloc_tos(), newname, NULL, NULL);
			TALLOC_FREE(newname);
			if (smb_fname_new == NULL) {
				errno = ENOMEM;
				goto fail;
			}

			if (SMB_VFS_NEXT_RENAME(handle, smb_fname_hash,
						smb_fname_new) == -1) {
				TALLOC_FREE(smb_fname_new);
				if ((errno == EEXIST) || (errno == ENOTEMPTY)) {
					goto again;
				}
				goto fail;
			}

			TALLOC_FREE(smb_fname_new);
		}
	}

	if (!create_it) {
		errno = ENOENT;
		goto fail;
	}

	if ((SMB_VFS_NEXT_MKDIR(handle, rootdir, 0755) != 0)
	    && (errno != EEXIST)) {
		goto fail;
	}

	tmp = talloc_asprintf(result, "%s/%2.2X", rootdir, first);
	if (tmp == NULL) {
		errno = ENOMEM;
		goto fail;
	}

	if ((SMB_VFS_NEXT_MKDIR(handle, tmp, 0755) != 0)
	    && (errno != EEXIST)) {
		goto fail;
	}

	TALLOC_FREE(tmp);

	tmp = talloc_asprintf(result, "%s/%2.2X/%2.2X", rootdir, first,
			      second);
	if (tmp == NULL) {
		errno = ENOMEM;
		goto fail;
	}

	if ((SMB_VFS_NEXT_MKDIR(handle, tmp, 0755) != 0)
	    && (errno != EEXIST)) {
		goto fail;
	}

	TALLOC_FREE(tmp);

	if ((SMB_VFS_NEXT_MKDIR(handle, result, 0755) != 0)
	    && (errno != EEXIST)) {
		goto fail;
	}

	if (check_valid && !mark_file_valid(handle, smb_fname->base_name)) {
		goto fail;
	}

	TALLOC_FREE(smb_fname_hash);
	return result;

 fail:
	TALLOC_FREE(smb_fname_hash);
	TALLOC_FREE(result);
	return NULL;
}
/**
 * Given a stream name, populate smb_fname_out with the actual location of the
 * stream.
 */
static NTSTATUS stream_smb_fname(vfs_handle_struct *handle,
				 const struct smb_filename *smb_fname,
				 struct smb_filename **smb_fname_out,
				 bool create_dir)
{
	char *dirname, *stream_fname;
	const char *stype;
	NTSTATUS status;

	*smb_fname_out = NULL;

	stype = strchr_m(smb_fname->stream_name + 1, ':');

	if (stype) {
		if (strcasecmp_m(stype, ":$DATA") != 0) {
			return NT_STATUS_INVALID_PARAMETER;
		}
	}

	dirname = stream_dir(handle, smb_fname, NULL, create_dir);

	if (dirname == NULL) {
		status = map_nt_error_from_unix(errno);
		goto fail;
	}

	stream_fname = talloc_asprintf(talloc_tos(), "%s/%s", dirname,
				       smb_fname->stream_name);

	if (stream_fname == NULL) {
		status = NT_STATUS_NO_MEMORY;
		goto fail;
	}

	if (stype == NULL) {
		/* Append an explicit stream type if one wasn't specified. */
		stream_fname = talloc_asprintf(talloc_tos(), "%s:$DATA",
					       stream_fname);
		if (stream_fname == NULL) {
			status = NT_STATUS_NO_MEMORY;
			goto fail;
		}
	} else {
		/* Normalize the stream type to upercase. */
		if (!strupper_m(strrchr_m(stream_fname, ':') + 1)) {
			status = NT_STATUS_INVALID_PARAMETER;
			goto fail;
		}
	}

	DEBUG(10, ("stream filename = %s\n", stream_fname));

	/* Create an smb_filename with stream_name == NULL. */
	*smb_fname_out = synthetic_smb_fname(
		talloc_tos(), stream_fname, NULL, NULL);
	if (*smb_fname_out == NULL) {
		return NT_STATUS_NO_MEMORY;
	}

	return NT_STATUS_OK;

 fail:
	DEBUG(5, ("stream_name failed: %s\n", strerror(errno)));
	TALLOC_FREE(*smb_fname_out);
	return status;
}

static NTSTATUS walk_streams(vfs_handle_struct *handle,
			     struct smb_filename *smb_fname_base,
			     char **pdirname,
			     bool (*fn)(const char *dirname,
					const char *dirent,
					void *private_data),
			     void *private_data)
{
	char *dirname;
	DIR *dirhandle = NULL;
	const char *dirent = NULL;
	char *talloced = NULL;

	dirname = stream_dir(handle, smb_fname_base, &smb_fname_base->st,
			     false);

	if (dirname == NULL) {
		if (errno == ENOENT) {
			/*
			 * no stream around
			 */
			return NT_STATUS_OK;
		}
		return map_nt_error_from_unix(errno);
	}

	DEBUG(10, ("walk_streams: dirname=%s\n", dirname));

	dirhandle = SMB_VFS_NEXT_OPENDIR(handle, dirname, NULL, 0);

	if (dirhandle == NULL) {
		TALLOC_FREE(dirname);
		return map_nt_error_from_unix(errno);
	}

	while ((dirent = vfs_readdirname(handle->conn, dirhandle, NULL,
					 &talloced)) != NULL) {

		if (ISDOT(dirent) || ISDOTDOT(dirent)) {
			TALLOC_FREE(talloced);
			continue;
		}

		DEBUG(10, ("walk_streams: dirent=%s\n", dirent));

		if (!fn(dirname, dirent, private_data)) {
			TALLOC_FREE(talloced);
			break;
		}
		TALLOC_FREE(talloced);
	}

	SMB_VFS_NEXT_CLOSEDIR(handle, dirhandle);

	if (pdirname != NULL) {
		*pdirname = dirname;
	}
	else {
		TALLOC_FREE(dirname);
	}

	return NT_STATUS_OK;
}

/**
 * Helper to stat/lstat the base file of an smb_fname. This will actually
 * fills in the stat struct in smb_filename.
 */
static int streams_depot_stat_base(vfs_handle_struct *handle,
				   struct smb_filename *smb_fname,
				   bool follow_links)
{
	char *tmp_stream_name;
	int result;

	tmp_stream_name = smb_fname->stream_name;
	smb_fname->stream_name = NULL;
	if (follow_links) {
		result = SMB_VFS_NEXT_STAT(handle, smb_fname);
	} else {
		result = SMB_VFS_NEXT_LSTAT(handle, smb_fname);
	}
	smb_fname->stream_name = tmp_stream_name;
	return result;
}

static int streams_depot_stat(vfs_handle_struct *handle,
			      struct smb_filename *smb_fname)
{
	struct smb_filename *smb_fname_stream = NULL;
	NTSTATUS status;
	int ret = -1;

	DEBUG(10, ("streams_depot_stat called for [%s]\n",
		   smb_fname_str_dbg(smb_fname)));

	if (!is_ntfs_stream_smb_fname(smb_fname)) {
		return SMB_VFS_NEXT_STAT(handle, smb_fname);
	}

	/* If the default stream is requested, just stat the base file. */
	if (is_ntfs_default_stream_smb_fname(smb_fname)) {
		return streams_depot_stat_base(handle, smb_fname, true);
	}

	/* Stat the actual stream now. */
	status = stream_smb_fname(handle, smb_fname, &smb_fname_stream,
				  false);
	if (!NT_STATUS_IS_OK(status)) {
		ret = -1;
		errno = map_errno_from_nt_status(status);
		goto done;
	}

	ret = SMB_VFS_NEXT_STAT(handle, smb_fname_stream);

	/* Update the original smb_fname with the stat info. */
	smb_fname->st = smb_fname_stream->st;
 done:
	TALLOC_FREE(smb_fname_stream);
	return ret;
}



static int streams_depot_lstat(vfs_handle_struct *handle,
			       struct smb_filename *smb_fname)
{
	struct smb_filename *smb_fname_stream = NULL;
	NTSTATUS status;
	int ret = -1;

	DEBUG(10, ("streams_depot_lstat called for [%s]\n",
		   smb_fname_str_dbg(smb_fname)));

	if (!is_ntfs_stream_smb_fname(smb_fname)) {
		return SMB_VFS_NEXT_LSTAT(handle, smb_fname);
	}

	/* If the default stream is requested, just stat the base file. */
	if (is_ntfs_default_stream_smb_fname(smb_fname)) {
		return streams_depot_stat_base(handle, smb_fname, false);
	}

	/* Stat the actual stream now. */
	status = stream_smb_fname(handle, smb_fname, &smb_fname_stream,
				  false);
	if (!NT_STATUS_IS_OK(status)) {
		ret = -1;
		errno = map_errno_from_nt_status(status);
		goto done;
	}

	ret = SMB_VFS_NEXT_LSTAT(handle, smb_fname_stream);

 done:
	TALLOC_FREE(smb_fname_stream);
	return ret;
}

static int streams_depot_open(vfs_handle_struct *handle,
			      struct smb_filename *smb_fname,
			      files_struct *fsp, int flags, mode_t mode)
{
	struct smb_filename *smb_fname_stream = NULL;
	struct smb_filename *smb_fname_base = NULL;
	NTSTATUS status;
	int ret = -1;

	if (!is_ntfs_stream_smb_fname(smb_fname)) {
		return SMB_VFS_NEXT_OPEN(handle, smb_fname, fsp, flags, mode);
	}

	/* If the default stream is requested, just open the base file. */
	if (is_ntfs_default_stream_smb_fname(smb_fname)) {
		char *tmp_stream_name;

		tmp_stream_name = smb_fname->stream_name;
		smb_fname->stream_name = NULL;
		ret = SMB_VFS_NEXT_OPEN(handle, smb_fname, fsp, flags, mode);
		smb_fname->stream_name = tmp_stream_name;

		return ret;
	}

	/* Ensure the base file still exists. */
	smb_fname_base = synthetic_smb_fname(
		talloc_tos(), smb_fname->base_name, NULL, NULL);
	if (smb_fname_base == NULL) {
		ret = -1;
		errno = ENOMEM;
		goto done;
	}

	ret = SMB_VFS_NEXT_STAT(handle, smb_fname_base);
	if (ret == -1) {
		goto done;
	}

	/* Determine the stream name, and then open it. */
	status = stream_smb_fname(handle, smb_fname, &smb_fname_stream, true);
	if (!NT_STATUS_IS_OK(status)) {
		ret = -1;
		errno = map_errno_from_nt_status(status);
		goto done;
	}

	ret = SMB_VFS_NEXT_OPEN(handle, smb_fname_stream, fsp, flags, mode);

 done:
	TALLOC_FREE(smb_fname_stream);
	TALLOC_FREE(smb_fname_base);
	return ret;
}

static int streams_depot_unlink(vfs_handle_struct *handle,
				const struct smb_filename *smb_fname)
{
	struct smb_filename *smb_fname_base = NULL;
	int ret = -1;

	DEBUG(10, ("streams_depot_unlink called for %s\n",
		   smb_fname_str_dbg(smb_fname)));

	/* If there is a valid stream, just unlink the stream and return. */
	if (is_ntfs_stream_smb_fname(smb_fname) &&
	    !is_ntfs_default_stream_smb_fname(smb_fname)) {
		struct smb_filename *smb_fname_stream = NULL;
		NTSTATUS status;

		status = stream_smb_fname(handle, smb_fname, &smb_fname_stream,
					  false);
		if (!NT_STATUS_IS_OK(status)) {
			errno = map_errno_from_nt_status(status);
			return -1;
		}

		ret = SMB_VFS_NEXT_UNLINK(handle, smb_fname_stream);

		TALLOC_FREE(smb_fname_stream);
		return ret;
	}

	/*
	 * We potentially need to delete the per-inode streams directory
	 */

	smb_fname_base = synthetic_smb_fname(
		talloc_tos(), smb_fname->base_name, NULL, NULL);
	if (smb_fname_base == NULL) {
		errno = ENOMEM;
		return -1;
	}

	if (lp_posix_pathnames()) {
		ret = SMB_VFS_NEXT_LSTAT(handle, smb_fname_base);
	} else {
		ret = SMB_VFS_NEXT_STAT(handle, smb_fname_base);
	}

	if (ret == -1) {
		TALLOC_FREE(smb_fname_base);
		return -1;
	}

	if (smb_fname_base->st.st_ex_nlink == 1) {
		char *dirname = stream_dir(handle, smb_fname_base,
					   &smb_fname_base->st, false);

		if (dirname != NULL) {
			SMB_VFS_NEXT_RMDIR(handle, dirname);
		}
		TALLOC_FREE(dirname);
	}

	ret = SMB_VFS_NEXT_UNLINK(handle, smb_fname);

	TALLOC_FREE(smb_fname_base);
	return ret;
}

static int streams_depot_rmdir(vfs_handle_struct *handle, const char *path)
{
	struct smb_filename *smb_fname_base = NULL;
	int ret = -1;

	DEBUG(10, ("streams_depot_rmdir called for %s\n", path));

	/*
	 * We potentially need to delete the per-inode streams directory
	 */

	smb_fname_base = synthetic_smb_fname(talloc_tos(), path, NULL, NULL);
	if (smb_fname_base == NULL) {
		errno = ENOMEM;
		return -1;
	}

	if (lp_posix_pathnames()) {
		ret = SMB_VFS_NEXT_LSTAT(handle, smb_fname_base);
	} else {
		ret = SMB_VFS_NEXT_STAT(handle, smb_fname_base);
	}

	if (ret == -1) {
		TALLOC_FREE(smb_fname_base);
		return -1;
	}

	if (smb_fname_base->st.st_ex_nlink == 2) {
		char *dirname = stream_dir(handle, smb_fname_base,
					   &smb_fname_base->st, false);

		if (dirname != NULL) {
			SMB_VFS_NEXT_RMDIR(handle, dirname);
		}
		TALLOC_FREE(dirname);
	}

	ret = SMB_VFS_NEXT_RMDIR(handle, path);

	TALLOC_FREE(smb_fname_base);
	return ret;
}

static int streams_depot_rename(vfs_handle_struct *handle,
				const struct smb_filename *smb_fname_src,
				const struct smb_filename *smb_fname_dst)
{
	struct smb_filename *smb_fname_src_stream = NULL;
	struct smb_filename *smb_fname_dst_stream = NULL;
	bool src_is_stream, dst_is_stream;
	NTSTATUS status;
	int ret = -1;

	DEBUG(10, ("streams_depot_rename called for %s => %s\n",
		   smb_fname_str_dbg(smb_fname_src),
		   smb_fname_str_dbg(smb_fname_dst)));

	src_is_stream = is_ntfs_stream_smb_fname(smb_fname_src);
	dst_is_stream = is_ntfs_stream_smb_fname(smb_fname_dst);

	if (!src_is_stream && !dst_is_stream) {
		return SMB_VFS_NEXT_RENAME(handle, smb_fname_src,
					   smb_fname_dst);
	}

	/* for now don't allow renames from or to the default stream */
	if (is_ntfs_default_stream_smb_fname(smb_fname_src) ||
	    is_ntfs_default_stream_smb_fname(smb_fname_dst)) {
		errno = ENOSYS;
		goto done;
	}

	status = stream_smb_fname(handle, smb_fname_src, &smb_fname_src_stream,
				  false);
	if (!NT_STATUS_IS_OK(status)) {
		errno = map_errno_from_nt_status(status);
		goto done;
	}

	status = stream_smb_fname(handle, smb_fname_dst,
				  &smb_fname_dst_stream, false);
	if (!NT_STATUS_IS_OK(status)) {
		errno = map_errno_from_nt_status(status);
		goto done;
	}

	ret = SMB_VFS_NEXT_RENAME(handle, smb_fname_src_stream,
				  smb_fname_dst_stream);

done:
	TALLOC_FREE(smb_fname_src_stream);
	TALLOC_FREE(smb_fname_dst_stream);
	return ret;
}

static bool add_one_stream(TALLOC_CTX *mem_ctx, unsigned int *num_streams,
			   struct stream_struct **streams,
			   const char *name, off_t size,
			   off_t alloc_size)
{
	struct stream_struct *tmp;

	tmp = talloc_realloc(mem_ctx, *streams, struct stream_struct,
				   (*num_streams)+1);
	if (tmp == NULL) {
		return false;
	}

	tmp[*num_streams].name = talloc_strdup(tmp, name);
	if (tmp[*num_streams].name == NULL) {
		return false;
	}

	tmp[*num_streams].size = size;
	tmp[*num_streams].alloc_size = alloc_size;

	*streams = tmp;
	*num_streams += 1;
	return true;
}

struct streaminfo_state {
	TALLOC_CTX *mem_ctx;
	vfs_handle_struct *handle;
	unsigned int num_streams;
	struct stream_struct *streams;
	NTSTATUS status;
};

static bool collect_one_stream(const char *dirname,
			       const char *dirent,
			       void *private_data)
{
	struct streaminfo_state *state =
		(struct streaminfo_state *)private_data;
	struct smb_filename *smb_fname = NULL;
	char *sname = NULL;
	bool ret;

	sname = talloc_asprintf(talloc_tos(), "%s/%s", dirname, dirent);
	if (sname == NULL) {
		state->status = NT_STATUS_NO_MEMORY;
		ret = false;
		goto out;
	}

	smb_fname = synthetic_smb_fname(talloc_tos(), sname, NULL, NULL);
	if (smb_fname == NULL) {
		state->status = NT_STATUS_NO_MEMORY;
		ret = false;
		goto out;
	}

	if (SMB_VFS_NEXT_STAT(state->handle, smb_fname) == -1) {
		DEBUG(10, ("Could not stat %s: %s\n", sname,
			   strerror(errno)));
		ret = true;
		goto out;
	}

	if (!add_one_stream(state->mem_ctx,
			    &state->num_streams, &state->streams,
			    dirent, smb_fname->st.st_ex_size,
			    SMB_VFS_GET_ALLOC_SIZE(state->handle->conn, NULL,
						   &smb_fname->st))) {
		state->status = NT_STATUS_NO_MEMORY;
		ret = false;
		goto out;
	}

	ret = true;
 out:
	TALLOC_FREE(sname);
	TALLOC_FREE(smb_fname);
	return ret;
}

static NTSTATUS streams_depot_streaminfo(vfs_handle_struct *handle,
					 struct files_struct *fsp,
					 const char *fname,
					 TALLOC_CTX *mem_ctx,
					 unsigned int *pnum_streams,
					 struct stream_struct **pstreams)
{
	struct smb_filename *smb_fname_base = NULL;
	int ret;
	NTSTATUS status;
	struct streaminfo_state state;

	status = create_synthetic_smb_fname(talloc_tos(), fname, NULL, NULL,
					    &smb_fname_base);
	if (!NT_STATUS_IS_OK(status)) {
		return status;
	}

	if ((fsp != NULL) && (fsp->fh->fd != -1)) {
		ret = SMB_VFS_NEXT_FSTAT(handle, fsp, &smb_fname_base->st);
	}
	else {
		if (lp_posix_pathnames()) {
			ret = SMB_VFS_NEXT_LSTAT(handle, smb_fname_base);
		} else {
			ret = SMB_VFS_NEXT_STAT(handle, smb_fname_base);
		}
	}

	if (ret == -1) {
		status = map_nt_error_from_unix(errno);
		goto out;
	}

	state.streams = *pstreams;
	state.num_streams = *pnum_streams;
	state.mem_ctx = mem_ctx;
	state.handle = handle;
	state.status = NT_STATUS_OK;

	status = walk_streams(handle, smb_fname_base, NULL, collect_one_stream,
			      &state);

	if (!NT_STATUS_IS_OK(status)) {
		TALLOC_FREE(state.streams);
		goto out;
	}

	if (!NT_STATUS_IS_OK(state.status)) {
		TALLOC_FREE(state.streams);
		status = state.status;
		goto out;
	}

	*pnum_streams = state.num_streams;
	*pstreams = state.streams;
	status = SMB_VFS_NEXT_STREAMINFO(handle, fsp, fname, mem_ctx, pnum_streams, pstreams);

 out:
	TALLOC_FREE(smb_fname_base);
	return status;
}

static uint32_t streams_depot_fs_capabilities(struct vfs_handle_struct *handle,
			enum timestamp_set_resolution *p_ts_res)
{
	return SMB_VFS_NEXT_FS_CAPABILITIES(handle, p_ts_res) | FILE_NAMED_STREAMS;
}

static struct vfs_fn_pointers vfs_streams_depot_fns = {
	.fs_capabilities_fn = streams_depot_fs_capabilities,
	.open_fn = streams_depot_open,
	.stat_fn = streams_depot_stat,
	.lstat_fn = streams_depot_lstat,
	.unlink_fn = streams_depot_unlink,
	.rmdir_fn = streams_depot_rmdir,
	.rename_fn = streams_depot_rename,
	.streaminfo_fn = streams_depot_streaminfo,
};

NTSTATUS vfs_streams_depot_init(void);
NTSTATUS vfs_streams_depot_init(void)
{
	return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "streams_depot",
				&vfs_streams_depot_fns);
}