summaryrefslogtreecommitdiff
path: root/source3/modules/vfs_acl_common.c
blob: 570d14b4b2c3df35fd7c30846bd6b3be00163b4a (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
/*
 * Store Windows ACLs in data store - common functions.
 * #included into modules/vfs_acl_xattr.c and modules/vfs_acl_tdb.c
 *
 * Copyright (C) Volker Lendecke, 2008
 * Copyright (C) Jeremy Allison, 2009
 *
 * 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/>.
 */

static NTSTATUS create_acl_blob(const struct security_descriptor *psd,
			DATA_BLOB *pblob,
			uint16_t hash_type,
			uint8_t hash[XATTR_SD_HASH_SIZE]);

static NTSTATUS get_acl_blob(TALLOC_CTX *ctx,
			vfs_handle_struct *handle,
			files_struct *fsp,
			const char *name,
			DATA_BLOB *pblob);

static NTSTATUS store_acl_blob_fsp(vfs_handle_struct *handle,
			files_struct *fsp,
			DATA_BLOB *pblob);

static NTSTATUS store_acl_blob_pathname(vfs_handle_struct *handle,
			const char *fname,
			DATA_BLOB *pblob);

#define HASH_SECURITY_INFO (OWNER_SECURITY_INFORMATION | \
				GROUP_SECURITY_INFORMATION | \
				DACL_SECURITY_INFORMATION | \
				SACL_SECURITY_INFORMATION)

/*******************************************************************
 Hash a security descriptor.
*******************************************************************/

static NTSTATUS hash_sd_sha256(struct security_descriptor *psd,
			uint8_t *hash)
{
	DATA_BLOB blob;
	SHA256_CTX tctx;
	NTSTATUS status;

	memset(hash, '\0', XATTR_SD_HASH_SIZE);
	status = create_acl_blob(psd, &blob, XATTR_SD_HASH_TYPE_SHA256, hash);
	if (!NT_STATUS_IS_OK(status)) {
		return status;
	}

	SHA256_Init(&tctx);
	SHA256_Update(&tctx, blob.data, blob.length);
	SHA256_Final(hash, &tctx);

	return NT_STATUS_OK;
}

/*******************************************************************
 Parse out a struct security_descriptor from a DATA_BLOB.
*******************************************************************/

static NTSTATUS parse_acl_blob(const DATA_BLOB *pblob,
				struct security_descriptor **ppdesc,
				uint16_t *p_hash_type,
				uint8_t hash[XATTR_SD_HASH_SIZE])
{
	TALLOC_CTX *ctx = talloc_tos();
	struct xattr_NTACL xacl;
	enum ndr_err_code ndr_err;
	size_t sd_size;

	ndr_err = ndr_pull_struct_blob(pblob, ctx, NULL, &xacl,
			(ndr_pull_flags_fn_t)ndr_pull_xattr_NTACL);

	if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
		DEBUG(5, ("parse_acl_blob: ndr_pull_xattr_NTACL failed: %s\n",
			ndr_errstr(ndr_err)));
		return ndr_map_error2ntstatus(ndr_err);;
	}

	switch (xacl.version) {
		case 2:
			*ppdesc = make_sec_desc(ctx, SEC_DESC_REVISION,
					xacl.info.sd_hs2->sd->type | SEC_DESC_SELF_RELATIVE,
					xacl.info.sd_hs2->sd->owner_sid,
					xacl.info.sd_hs2->sd->group_sid,
					xacl.info.sd_hs2->sd->sacl,
					xacl.info.sd_hs2->sd->dacl,
					&sd_size);
			/* No hash - null out. */
			*p_hash_type = XATTR_SD_HASH_TYPE_NONE;
			memset(hash, '\0', XATTR_SD_HASH_SIZE);
			break;
		case 3:
			*ppdesc = make_sec_desc(ctx, SEC_DESC_REVISION,
					xacl.info.sd_hs3->sd->type | SEC_DESC_SELF_RELATIVE,
					xacl.info.sd_hs3->sd->owner_sid,
					xacl.info.sd_hs3->sd->group_sid,
					xacl.info.sd_hs3->sd->sacl,
					xacl.info.sd_hs3->sd->dacl,
					&sd_size);
			*p_hash_type = xacl.info.sd_hs3->hash_type;
			/* Current version 3. */
			memcpy(hash, xacl.info.sd_hs3->hash, XATTR_SD_HASH_SIZE);
			break;
		default:
			return NT_STATUS_REVISION_MISMATCH;
	}

	TALLOC_FREE(xacl.info.sd);

	return (*ppdesc != NULL) ? NT_STATUS_OK : NT_STATUS_NO_MEMORY;
}

/*******************************************************************
 Create a DATA_BLOB from a security descriptor.
*******************************************************************/

static NTSTATUS create_acl_blob(const struct security_descriptor *psd,
			DATA_BLOB *pblob,
			uint16_t hash_type,
			uint8_t hash[XATTR_SD_HASH_SIZE])
{
	struct xattr_NTACL xacl;
	struct security_descriptor_hash_v3 sd_hs3;
	enum ndr_err_code ndr_err;
	TALLOC_CTX *ctx = talloc_tos();

	ZERO_STRUCT(xacl);
	ZERO_STRUCT(sd_hs3);

	xacl.version = 3;
	xacl.info.sd_hs3 = &sd_hs3;
	xacl.info.sd_hs3->sd = CONST_DISCARD(struct security_descriptor *, psd);
	xacl.info.sd_hs3->hash_type = hash_type;
	memcpy(&xacl.info.sd_hs3->hash[0], hash, XATTR_SD_HASH_SIZE);

	ndr_err = ndr_push_struct_blob(
			pblob, ctx, NULL, &xacl,
			(ndr_push_flags_fn_t)ndr_push_xattr_NTACL);

	if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
		DEBUG(5, ("create_acl_blob: ndr_push_xattr_NTACL failed: %s\n",
			ndr_errstr(ndr_err)));
		return ndr_map_error2ntstatus(ndr_err);;
	}

	return NT_STATUS_OK;
}

/*******************************************************************
 Pull a DATA_BLOB from an xattr given a pathname.
 If the hash doesn't match, or doesn't exist - return the underlying
 filesystem sd.
*******************************************************************/

static NTSTATUS get_nt_acl_internal(vfs_handle_struct *handle,
				files_struct *fsp,
				const char *name,
			        uint32_t security_info,
				struct security_descriptor **ppdesc)
{
	DATA_BLOB blob;
	NTSTATUS status;
	uint16_t hash_type;
	uint8_t hash[XATTR_SD_HASH_SIZE];
	uint8_t hash_tmp[XATTR_SD_HASH_SIZE];
	struct security_descriptor *psd = NULL;
	struct security_descriptor *pdesc_next = NULL;

	if (fsp && name == NULL) {
		name = fsp->fsp_name->base_name;
	}

	DEBUG(10, ("get_nt_acl_internal: name=%s\n", name));

	/* Get the full underlying sd for the hash
	   or to return as backup. */
	if (fsp) {
		status = SMB_VFS_NEXT_FGET_NT_ACL(handle,
				fsp,
				HASH_SECURITY_INFO,
				&pdesc_next);
	} else {
		status = SMB_VFS_NEXT_GET_NT_ACL(handle,
				name,
				HASH_SECURITY_INFO,
				&pdesc_next);
	}

	if (!NT_STATUS_IS_OK(status)) {
		DEBUG(10, ("get_nt_acl_internal: get_next_acl for file %s "
			"returned %s\n",
			name,
			nt_errstr(status)));
		return status;
	}

	status = get_acl_blob(talloc_tos(), handle, fsp, name, &blob);
	if (!NT_STATUS_IS_OK(status)) {
		DEBUG(10, ("get_nt_acl_internal: get_acl_blob returned %s\n",
			nt_errstr(status)));
		psd = pdesc_next;
		goto out;
	}

	status = parse_acl_blob(&blob, &psd,
				&hash_type, &hash[0]);
	if (!NT_STATUS_IS_OK(status)) {
		DEBUG(10, ("parse_acl_blob returned %s\n",
				nt_errstr(status)));
		psd = pdesc_next;
		goto out;
	}

	/* Ensure the hash type is one we know. */
	switch (hash_type) {
		case XATTR_SD_HASH_TYPE_NONE:
			/* No hash, just return blob sd. */
			goto out;
		case XATTR_SD_HASH_TYPE_SHA256:
			break;
		default:
			DEBUG(10, ("get_nt_acl_internal: ACL blob revision "
				"mismatch (%u) for file %s\n",
				(unsigned int)hash_type,
				name));
			TALLOC_FREE(psd);
			psd = pdesc_next;
			goto out;
	}


	status = hash_sd_sha256(pdesc_next, hash_tmp);
	if (!NT_STATUS_IS_OK(status)) {
		TALLOC_FREE(psd);
		psd = pdesc_next;
		goto out;
	}

	if (memcmp(&hash[0], &hash_tmp[0], XATTR_SD_HASH_SIZE) == 0) {
		/* Hash matches, return blob sd. */
		goto out;
	}

	/* Hash doesn't match, return underlying sd. */
	TALLOC_FREE(psd);
	psd = pdesc_next;

  out:

	if (psd != pdesc_next) {
		/* We're returning the blob, throw
 		 * away the filesystem SD. */
		TALLOC_FREE(pdesc_next);
	}

	if (!(security_info & OWNER_SECURITY_INFORMATION)) {
		psd->owner_sid = NULL;
	}
	if (!(security_info & GROUP_SECURITY_INFORMATION)) {
		psd->group_sid = NULL;
	}
	if (!(security_info & DACL_SECURITY_INFORMATION)) {
		psd->dacl = NULL;
	}
	if (!(security_info & SACL_SECURITY_INFORMATION)) {
		psd->sacl = NULL;
	}

	TALLOC_FREE(blob.data);
	*ppdesc = psd;
	return NT_STATUS_OK;
}

#if 0
/*********************************************************************
 Create a default security descriptor for a file in case no inheritance
 exists. All permissions to the owner and SYSTEM.
*********************************************************************/

static struct security_descriptor *default_file_sd(TALLOC_CTX *mem_ctx,
						SMB_STRUCT_STAT *psbuf,
						bool force_inherit)
{
	struct dom_sid owner_sid, group_sid;
	size_t sd_size;
	struct security_ace *pace = NULL;
	struct security_acl *pacl = NULL;

	uid_to_sid(&owner_sid, psbuf->st_ex_uid);
	gid_to_sid(&group_sid, psbuf->st_ex_gid);

	pace = TALLOC_ARRAY(mem_ctx, struct security_ace, 2);
	if (!pace) {
		return NULL;
	}

	/* If force_inherit is set, this means we are initializing the ACEs for
	 * a container and we want the ACEs for owner_sid and "SYSTEM" to be
	 * inheritable by their children (See Bug #6802).
	 */

	init_sec_ace(&pace[0], &owner_sid, SEC_ACE_TYPE_ACCESS_ALLOWED,
			SEC_RIGHTS_FILE_ALL, (force_inherit ?
					(SEC_ACE_FLAG_OBJECT_INHERIT|
					SEC_ACE_FLAG_CONTAINER_INHERIT) :
					0));

	init_sec_ace(&pace[1], &global_sid_System, SEC_ACE_TYPE_ACCESS_ALLOWED,
			SEC_RIGHTS_FILE_ALL, (force_inherit ?
					(SEC_ACE_FLAG_OBJECT_INHERIT|
					SEC_ACE_FLAG_CONTAINER_INHERIT) :
					0));

	pacl = make_sec_acl(mem_ctx,
				NT4_ACL_REVISION,
				2,
				pace);
	if (!pacl) {
		return NULL;
	}
	return make_sec_desc(mem_ctx,
			SECURITY_DESCRIPTOR_REVISION_1,
			SEC_DESC_SELF_RELATIVE|SEC_DESC_DACL_PRESENT,
			&owner_sid,
			&group_sid,
			NULL,
                        pacl,
			&sd_size);
}
#endif

/*********************************************************************
 Create a default ACL by inheriting from the parent. If no inheritance
 from the parent available, just use the actual permissions the new
 file or directory already got from the filesystem.
*********************************************************************/

static NTSTATUS inherit_new_acl(vfs_handle_struct *handle,
					struct smb_filename *smb_fname,
					files_struct *fsp,
					struct security_descriptor *parent_desc,
					bool is_directory)
{
	TALLOC_CTX *ctx = talloc_tos();
	NTSTATUS status = NT_STATUS_OK;
	struct security_descriptor *psd = NULL;
	struct security_descriptor *pdesc_next = NULL;
	DATA_BLOB blob;
	size_t size;
	uint8_t hash[XATTR_SD_HASH_SIZE];

	if (parent_desc == NULL) {
		/* We don't already have the parent sd, fetch it now. */
		char *parent_name;

		if (!parent_dirname(ctx, smb_fname->base_name, &parent_name, NULL)) {
			return NT_STATUS_NO_MEMORY;
		}

		DEBUG(10,("inherit_new_acl: check directory %s\n",
				parent_name));

		status = get_nt_acl_internal(handle,
				NULL,
				parent_name,
				(OWNER_SECURITY_INFORMATION |
				 GROUP_SECURITY_INFORMATION |
				 DACL_SECURITY_INFORMATION),
				&parent_desc);

		if (!NT_STATUS_IS_OK(status)) {
			DEBUG(10,("inherit_new_acl: directory %s failed "
				"to get acl BLOB %s\n",
				parent_name,
				nt_errstr(status) ));
			return status;
		}
	}

	/*
	 * Object must exist. Read the current SD off the filesystem
	 * for the hash.
	 */
	if (fsp) {
		status = SMB_VFS_NEXT_FGET_NT_ACL(handle,
				fsp,
				HASH_SECURITY_INFO,
				&pdesc_next);
	} else {
		status = SMB_VFS_NEXT_GET_NT_ACL(handle,
				smb_fname->base_name,
				HASH_SECURITY_INFO,
				&pdesc_next);
	}

	if (!NT_STATUS_IS_OK(status)) {
		DEBUG(10,("inherit_new_acl: get_next_acl \n"
			"failed for %s (%s)\n",
			smb_fname_str_dbg(smb_fname),
			nt_errstr(status) ));
		return status;
	}

	if (parent_desc && sd_has_inheritable_components(parent_desc, is_directory)) {
		/* Create an inherited descriptor from the parent. */

		if (DEBUGLEVEL >= 10) {
			DEBUG(10,("inherit_new_acl: parent acl is:\n"));
			NDR_PRINT_DEBUG(security_descriptor, parent_desc);
		}

		status = se_create_child_secdesc(ctx,
				&psd,
				&size,
				parent_desc,
				&handle->conn->server_info->ptok->user_sids[PRIMARY_USER_SID_INDEX],
				&handle->conn->server_info->ptok->user_sids[PRIMARY_GROUP_SID_INDEX],
				is_directory);
		if (!NT_STATUS_IS_OK(status)) {
			return status;
		}

	} else {
		DEBUG(10,("inherit_new_acl: using current permissions.\n"
			"to set Windows acl for %s\n",
			smb_fname_str_dbg(smb_fname) ));
		psd = pdesc_next;
	}

	if (DEBUGLEVEL >= 10) {
		DEBUG(10,("inherit_new_acl: child acl is:\n"));
		NDR_PRINT_DEBUG(security_descriptor, psd);
	}

	status = hash_sd_sha256(pdesc_next, hash);
	if (!NT_STATUS_IS_OK(status)) {
		return status;
	}
	status = create_acl_blob(psd, &blob, XATTR_SD_HASH_TYPE_SHA256, hash);
	if (!NT_STATUS_IS_OK(status)) {
		return status;
	}
	if (fsp) {
		return store_acl_blob_fsp(handle, fsp, &blob);
	} else {
		return store_acl_blob_pathname(handle, smb_fname->base_name,
					       &blob);
	}
}

static NTSTATUS check_parent_acl_common(vfs_handle_struct *handle,
				const char *path,
				uint32_t access_mask,
				struct security_descriptor **pp_parent_desc)
{
	char *parent_name = NULL;
	struct security_descriptor *parent_desc = NULL;
	uint32_t access_granted = 0;
	NTSTATUS status;

	if (!parent_dirname(talloc_tos(), path, &parent_name, NULL)) {
		return NT_STATUS_NO_MEMORY;
	}

	status = get_nt_acl_internal(handle,
					NULL,
					parent_name,
					(OWNER_SECURITY_INFORMATION |
					 GROUP_SECURITY_INFORMATION |
					 DACL_SECURITY_INFORMATION),
					&parent_desc);

	if (!NT_STATUS_IS_OK(status)) {
		DEBUG(10,("check_parent_acl_common: get_nt_acl_internal "
			"on directory %s for "
			"path %s returned %s\n",
			parent_name,
			path,
			nt_errstr(status) ));
		return status;
	}
	status = smb1_file_se_access_check(parent_desc,
					handle->conn->server_info->ptok,
					access_mask,
					&access_granted);
	if(!NT_STATUS_IS_OK(status)) {
		DEBUG(10,("check_parent_acl_common: access check "
			"on directory %s for "
			"path %s for mask 0x%x returned %s\n",
			parent_name,
			path,
			access_mask,
			nt_errstr(status) ));
		return status;
	}
	if (pp_parent_desc) {
		*pp_parent_desc = parent_desc;
	}
	return NT_STATUS_OK;
}

/*********************************************************************
 Check ACL on open. For new files inherit from parent directory.
*********************************************************************/

static int open_acl_common(vfs_handle_struct *handle,
			struct smb_filename *smb_fname,
			files_struct *fsp,
			int flags,
			mode_t mode)
{
	uint32_t access_granted = 0;
	struct security_descriptor *pdesc = NULL;
	struct security_descriptor *parent_desc = NULL;
	bool file_existed = true;
	char *fname = NULL;
	NTSTATUS status;

	if (fsp->base_fsp) {
		/* Stream open. Base filename open already did the ACL check. */
		DEBUG(10,("open_acl_common: stream open on %s\n",
			smb_fname_str_dbg(smb_fname) ));
		return SMB_VFS_NEXT_OPEN(handle, smb_fname, fsp, flags, mode);
	}

	status = get_full_smb_filename(talloc_tos(), smb_fname,
				       &fname);
	if (!NT_STATUS_IS_OK(status)) {
		goto err;
	}

	status = get_nt_acl_internal(handle,
				NULL,
				fname,
				(OWNER_SECURITY_INFORMATION |
				 GROUP_SECURITY_INFORMATION |
				 DACL_SECURITY_INFORMATION),
				&pdesc);
        if (NT_STATUS_IS_OK(status)) {
		/* See if we can access it. */
		status = smb1_file_se_access_check(pdesc,
					handle->conn->server_info->ptok,
					fsp->access_mask,
					&access_granted);
		if (!NT_STATUS_IS_OK(status)) {
			DEBUG(10,("open_acl_xattr: file %s open "
				"refused with error %s\n",
				smb_fname_str_dbg(smb_fname),
				nt_errstr(status) ));
			goto err;
		}
        } else if (NT_STATUS_EQUAL(status,NT_STATUS_OBJECT_NAME_NOT_FOUND)) {
		file_existed = false;
		/*
		 * If O_CREAT is true then we're trying to create a file.
		 * Check the parent directory ACL will allow this.
		 */
		if (flags & O_CREAT) {
			status = check_parent_acl_common(handle, fname,
					SEC_DIR_ADD_FILE, &parent_desc);
			if (!NT_STATUS_IS_OK(status)) {
				goto err;
			}
		}
	}

	DEBUG(10,("open_acl_xattr: get_nt_acl_attr_internal for "
		"file %s returned %s\n",
		smb_fname_str_dbg(smb_fname),
		nt_errstr(status) ));

	fsp->fh->fd = SMB_VFS_NEXT_OPEN(handle, smb_fname, fsp, flags, mode);

	if (!file_existed && fsp->fh->fd != -1) {
		/* File was created. Inherit from parent directory. */
		status = fsp_set_smb_fname(fsp, smb_fname);
		if (!NT_STATUS_IS_OK(status)) {
			goto err;
		}
		inherit_new_acl(handle, smb_fname, fsp, parent_desc, false);
	}

	return fsp->fh->fd;

  err:

	errno = map_errno_from_nt_status(status);
	return -1;
}

static int mkdir_acl_common(vfs_handle_struct *handle, const char *path, mode_t mode)
{
	struct smb_filename *smb_fname = NULL;
	int ret;
	NTSTATUS status;
	SMB_STRUCT_STAT sbuf;
	struct security_descriptor *parent_desc = NULL;

	ret = vfs_stat_smb_fname(handle->conn, path, &sbuf);
	if (ret == -1 && errno == ENOENT) {
		/* We're creating a new directory. */
		status = check_parent_acl_common(handle, path,
				SEC_DIR_ADD_SUBDIR, &parent_desc);
		if (!NT_STATUS_IS_OK(status)) {
			errno = map_errno_from_nt_status(status);
			return -1;
		}
	}

	ret = SMB_VFS_NEXT_MKDIR(handle, path, mode);
	if (ret == -1) {
		return ret;
	}

	status = create_synthetic_smb_fname(talloc_tos(), path, NULL, NULL,
					    &smb_fname);
	if (!NT_STATUS_IS_OK(status)) {
		errno = map_errno_from_nt_status(status);
		return -1;
	}

	/* New directory - inherit from parent. */
	inherit_new_acl(handle, smb_fname, NULL, parent_desc, true);
	TALLOC_FREE(smb_fname);
	return ret;
}

/*********************************************************************
 Fetch a security descriptor given an fsp.
*********************************************************************/

static NTSTATUS fget_nt_acl_common(vfs_handle_struct *handle, files_struct *fsp,
        uint32_t security_info, struct security_descriptor **ppdesc)
{
	return get_nt_acl_internal(handle, fsp,
				NULL, security_info, ppdesc);
}

/*********************************************************************
 Fetch a security descriptor given a pathname.
*********************************************************************/

static NTSTATUS get_nt_acl_common(vfs_handle_struct *handle,
        const char *name, uint32_t security_info, struct security_descriptor **ppdesc)
{
	return get_nt_acl_internal(handle, NULL,
				name, security_info, ppdesc);
}

/*********************************************************************
 Store a security descriptor given an fsp.
*********************************************************************/

static NTSTATUS fset_nt_acl_common(vfs_handle_struct *handle, files_struct *fsp,
        uint32_t security_info_sent, const struct security_descriptor *psd)
{
	NTSTATUS status;
	DATA_BLOB blob;
	struct security_descriptor *pdesc_next = NULL;
	uint8_t hash[XATTR_SD_HASH_SIZE];

	if (DEBUGLEVEL >= 10) {
		DEBUG(10,("fset_nt_acl_xattr: incoming sd for file %s\n",
			  fsp_str_dbg(fsp)));
		NDR_PRINT_DEBUG(security_descriptor,
			CONST_DISCARD(struct security_descriptor *,psd));
	}

        /* Ensure we have OWNER/GROUP/DACL set. */

	if ((security_info_sent & (OWNER_SECURITY_INFORMATION|
				GROUP_SECURITY_INFORMATION|
				DACL_SECURITY_INFORMATION)) !=
				(OWNER_SECURITY_INFORMATION|
				 GROUP_SECURITY_INFORMATION|
				 DACL_SECURITY_INFORMATION)) {
		/* No we don't - read from the existing SD. */
		struct security_descriptor *nc_psd = NULL;

		status = get_nt_acl_internal(handle, fsp,
				NULL,
				(OWNER_SECURITY_INFORMATION|
				 GROUP_SECURITY_INFORMATION|
				 DACL_SECURITY_INFORMATION),
				&nc_psd);

		if (!NT_STATUS_IS_OK(status)) {
			return status;
		}

		/* This is safe as nc_psd is discarded at fn exit. */
		if (security_info_sent & OWNER_SECURITY_INFORMATION) {
			nc_psd->owner_sid = psd->owner_sid;
		}
		security_info_sent |= OWNER_SECURITY_INFORMATION;

		if (security_info_sent & GROUP_SECURITY_INFORMATION) {
			nc_psd->group_sid = psd->group_sid;
		}
		security_info_sent |= GROUP_SECURITY_INFORMATION;

		if (security_info_sent & DACL_SECURITY_INFORMATION) {
			nc_psd->dacl = dup_sec_acl(talloc_tos(), psd->dacl);
			if (nc_psd->dacl == NULL) {
				return NT_STATUS_NO_MEMORY;
			}
		}
		security_info_sent |= DACL_SECURITY_INFORMATION;
		psd = nc_psd;
	}

	status = SMB_VFS_NEXT_FSET_NT_ACL(handle, fsp, security_info_sent, psd);
	if (!NT_STATUS_IS_OK(status)) {
		return status;
	}

	/* Get the full underlying sd, then hash. */
	status = SMB_VFS_NEXT_FGET_NT_ACL(handle,
				fsp,
				HASH_SECURITY_INFO,
				&pdesc_next);

	if (!NT_STATUS_IS_OK(status)) {
		return status;
	}

	status = hash_sd_sha256(pdesc_next, hash);
	if (!NT_STATUS_IS_OK(status)) {
		return status;
	}

	if (DEBUGLEVEL >= 10) {
		DEBUG(10,("fset_nt_acl_xattr: storing xattr sd for file %s\n",
			  fsp_str_dbg(fsp)));
		NDR_PRINT_DEBUG(security_descriptor,
			CONST_DISCARD(struct security_descriptor *,psd));
	}
	create_acl_blob(psd, &blob, XATTR_SD_HASH_TYPE_SHA256, hash);
	store_acl_blob_fsp(handle, fsp, &blob);

	return NT_STATUS_OK;
}

static SMB_STRUCT_DIR *opendir_acl_common(vfs_handle_struct *handle,
			const char *fname, const char *mask, uint32 attr)
{
	NTSTATUS status = check_parent_acl_common(handle, fname,
					SEC_DIR_LIST, NULL);

	if (!NT_STATUS_IS_OK(status)) {
		errno = map_errno_from_nt_status(status);
		return NULL;
	}
	return SMB_VFS_NEXT_OPENDIR(handle, fname, mask, attr);
}