summaryrefslogtreecommitdiff
path: root/source3/lib/secdesc.c
blob: a443f90dbb4aaeebaa823f9d43e8ba9b1349f40d (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
/* 
 *  Unix SMB/Netbios implementation.
 *  SEC_DESC handling functions
 *  Copyright (C) Andrew Tridgell              1992-1998,
 *  Copyright (C) Jeremy R. Allison            1995-2003.
 *  Copyright (C) Luke Kenneth Casson Leighton 1996-1998,
 *  Copyright (C) Paul Ashton                  1997-1998.
 *  
 *  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.
 */

#include "includes.h"

/* Map generic permissions to file object specific permissions */

struct generic_mapping file_generic_mapping = {
	FILE_GENERIC_READ,
	FILE_GENERIC_WRITE,
	FILE_GENERIC_EXECUTE,
	FILE_GENERIC_ALL
};

/*******************************************************************
 Works out the linearization size of a SEC_DESC.
********************************************************************/

size_t sec_desc_size(SEC_DESC *psd)
{
	size_t offset;

	if (!psd) return 0;

	offset = SEC_DESC_HEADER_SIZE;

	/* don't align */

	if (psd->owner_sid != NULL)
		offset += sid_size(psd->owner_sid);

	if (psd->grp_sid != NULL)
		offset += sid_size(psd->grp_sid);

	if (psd->sacl != NULL)
		offset += psd->sacl->size;

	if (psd->dacl != NULL)
		offset += psd->dacl->size;

	return offset;
}

/*******************************************************************
 Compares two SEC_DESC structures
********************************************************************/

BOOL sec_desc_equal(SEC_DESC *s1, SEC_DESC *s2)
{
	/* Trivial case */

	if (!s1 && !s2) {
		goto done;
	}

	if (!s1 || !s2) {
		return False;
	}

	/* Check top level stuff */

	if (s1->revision != s2->revision) {
		DEBUG(10, ("sec_desc_equal(): revision differs (%d != %d)\n",
			   s1->revision, s2->revision));
		return False;
	}

	if (s1->type!= s2->type) {
		DEBUG(10, ("sec_desc_equal(): type differs (%d != %d)\n",
			   s1->type, s2->type));
		return False;
	}

	/* Check owner and group */

	if (!sid_equal(s1->owner_sid, s2->owner_sid)) {
		fstring str1, str2;

		sid_to_string(str1, s1->owner_sid);
		sid_to_string(str2, s2->owner_sid);

		DEBUG(10, ("sec_desc_equal(): owner differs (%s != %s)\n",
			   str1, str2));
		return False;
	}

	if (!sid_equal(s1->grp_sid, s2->grp_sid)) {
		fstring str1, str2;

		sid_to_string(str1, s1->grp_sid);
		sid_to_string(str2, s2->grp_sid);

		DEBUG(10, ("sec_desc_equal(): group differs (%s != %s)\n",
			   str1, str2));
		return False;
	}

	/* Check ACLs present in one but not the other */

	if ((s1->dacl && !s2->dacl) || (!s1->dacl && s2->dacl) ||
	    (s1->sacl && !s2->sacl) || (!s1->sacl && s2->sacl)) {
		DEBUG(10, ("sec_desc_equal(): dacl or sacl not present\n"));
		return False;
	}

	/* Sigh - we have to do it the hard way by iterating over all
	   the ACEs in the ACLs */

	if (!sec_acl_equal(s1->dacl, s2->dacl) ||
	    !sec_acl_equal(s1->sacl, s2->sacl)) {
		DEBUG(10, ("sec_desc_equal(): dacl/sacl list not equal\n"));
		return False;
	}

 done:
	DEBUG(10, ("sec_desc_equal(): secdescs are identical\n"));
	return True;
}

/*******************************************************************
 Merge part of security descriptor old_sec in to the empty sections of 
 security descriptor new_sec.
********************************************************************/

SEC_DESC_BUF *sec_desc_merge(TALLOC_CTX *ctx, SEC_DESC_BUF *new_sdb, SEC_DESC_BUF *old_sdb)
{
	DOM_SID *owner_sid, *group_sid;
	SEC_DESC_BUF *return_sdb;
	SEC_ACL *dacl, *sacl;
	SEC_DESC *psd = NULL;
	uint16 secdesc_type;
	size_t secdesc_size;

	/* Copy over owner and group sids.  There seems to be no flag for
	   this so just check the pointer values. */

	owner_sid = new_sdb->sec->owner_sid ? new_sdb->sec->owner_sid :
		old_sdb->sec->owner_sid;

	group_sid = new_sdb->sec->grp_sid ? new_sdb->sec->grp_sid :
		old_sdb->sec->grp_sid;
	
	secdesc_type = new_sdb->sec->type;

	/* Ignore changes to the system ACL.  This has the effect of making
	   changes through the security tab audit button not sticking. 
	   Perhaps in future Samba could implement these settings somehow. */

	sacl = NULL;
	secdesc_type &= ~SEC_DESC_SACL_PRESENT;

	/* Copy across discretionary ACL */

	if (secdesc_type & SEC_DESC_DACL_PRESENT) {
		dacl = new_sdb->sec->dacl;
	} else {
		dacl = old_sdb->sec->dacl;
	}

	/* Create new security descriptor from bits */

	psd = make_sec_desc(ctx, new_sdb->sec->revision, secdesc_type,
			    owner_sid, group_sid, sacl, dacl, &secdesc_size);

	return_sdb = make_sec_desc_buf(ctx, secdesc_size, psd);

	return(return_sdb);
}

/*******************************************************************
 Creates a SEC_DESC structure
********************************************************************/

SEC_DESC *make_sec_desc(TALLOC_CTX *ctx, uint16 revision, uint16 type,
			const DOM_SID *owner_sid, const DOM_SID *grp_sid,
			SEC_ACL *sacl, SEC_ACL *dacl, size_t *sd_size)
{
	SEC_DESC *dst;
	uint32 offset     = 0;

	*sd_size = 0;

	if(( dst = TALLOC_ZERO_P(ctx, SEC_DESC)) == NULL)
		return NULL;

	dst->revision = revision;
	dst->type = type;

	if (sacl)
		dst->type |= SEC_DESC_SACL_PRESENT;
	if (dacl)
		dst->type |= SEC_DESC_DACL_PRESENT;

	dst->off_owner_sid = 0;
	dst->off_grp_sid   = 0;
	dst->off_sacl      = 0;
	dst->off_dacl      = 0;

	if(owner_sid && ((dst->owner_sid = sid_dup_talloc(ctx,owner_sid)) == NULL))
		goto error_exit;

	if(grp_sid && ((dst->grp_sid = sid_dup_talloc(ctx,grp_sid)) == NULL))
		goto error_exit;

	if(sacl && ((dst->sacl = dup_sec_acl(ctx, sacl)) == NULL))
		goto error_exit;

	if(dacl && ((dst->dacl = dup_sec_acl(ctx, dacl)) == NULL))
		goto error_exit;

	offset = SEC_DESC_HEADER_SIZE;

	/*
	 * Work out the linearization sizes.
	 */

	if (dst->sacl != NULL) {
		dst->off_sacl = offset;
		offset += dst->sacl->size;
	}
	if (dst->dacl != NULL) {
		dst->off_dacl = offset;
		offset += dst->dacl->size;
	}

	if (dst->owner_sid != NULL) {
		dst->off_owner_sid = offset;
		offset += sid_size(dst->owner_sid);
	}

	if (dst->grp_sid != NULL) {
		dst->off_grp_sid = offset;
		offset += sid_size(dst->grp_sid);
	}

	*sd_size = (size_t)offset;
	return dst;

error_exit:

	*sd_size = 0;
	return NULL;
}

/*******************************************************************
 Duplicate a SEC_DESC structure.  
********************************************************************/

SEC_DESC *dup_sec_desc(TALLOC_CTX *ctx, const SEC_DESC *src)
{
	size_t dummy;

	if(src == NULL)
		return NULL;

	return make_sec_desc( ctx, src->revision, src->type,
				src->owner_sid, src->grp_sid, src->sacl,
				src->dacl, &dummy);
}

/*******************************************************************
 Creates a SEC_DESC structure with typical defaults.
********************************************************************/

SEC_DESC *make_standard_sec_desc(TALLOC_CTX *ctx, const DOM_SID *owner_sid, const DOM_SID *grp_sid,
				 SEC_ACL *dacl, size_t *sd_size)
{
	return make_sec_desc(ctx, SEC_DESC_REVISION, SEC_DESC_SELF_RELATIVE,
			     owner_sid, grp_sid, NULL, dacl, sd_size);
}

/*******************************************************************
 Creates a SEC_DESC_BUF structure.
********************************************************************/

SEC_DESC_BUF *make_sec_desc_buf(TALLOC_CTX *ctx, size_t len, SEC_DESC *sec_desc)
{
	SEC_DESC_BUF *dst;

	if((dst = TALLOC_ZERO_P(ctx, SEC_DESC_BUF)) == NULL)
		return NULL;

	/* max buffer size (allocated size) */
	dst->max_len = (uint32)len;
	dst->len = (uint32)len;
	
	if(sec_desc && ((dst->sec = dup_sec_desc(ctx, sec_desc)) == NULL)) {
		return NULL;
	}

	dst->ptr = 0x1;

	return dst;
}

/*******************************************************************
 Duplicates a SEC_DESC_BUF structure.
********************************************************************/

SEC_DESC_BUF *dup_sec_desc_buf(TALLOC_CTX *ctx, SEC_DESC_BUF *src)
{
	if(src == NULL)
		return NULL;

	return make_sec_desc_buf( ctx, src->len, src->sec);
}

/*******************************************************************
 Add a new SID with its permissions to SEC_DESC.
********************************************************************/

NTSTATUS sec_desc_add_sid(TALLOC_CTX *ctx, SEC_DESC **psd, DOM_SID *sid, uint32 mask, size_t *sd_size)
{
	SEC_DESC *sd   = 0;
	SEC_ACL  *dacl = 0;
	SEC_ACE  *ace  = 0;
	NTSTATUS  status;

	*sd_size = 0;

	if (!ctx || !psd || !sid || !sd_size)
		return NT_STATUS_INVALID_PARAMETER;

	status = sec_ace_add_sid(ctx, &ace, psd[0]->dacl->ace, &psd[0]->dacl->num_aces, sid, mask);
	
	if (!NT_STATUS_IS_OK(status))
		return status;

	if (!(dacl = make_sec_acl(ctx, psd[0]->dacl->revision, psd[0]->dacl->num_aces, ace)))
		return NT_STATUS_UNSUCCESSFUL;
	
	if (!(sd = make_sec_desc(ctx, psd[0]->revision, psd[0]->type, psd[0]->owner_sid, 
		psd[0]->grp_sid, psd[0]->sacl, dacl, sd_size)))
		return NT_STATUS_UNSUCCESSFUL;

	*psd = sd;
	 sd  = 0;
	return NT_STATUS_OK;
}

/*******************************************************************
 Modify a SID's permissions in a SEC_DESC.
********************************************************************/

NTSTATUS sec_desc_mod_sid(SEC_DESC *sd, DOM_SID *sid, uint32 mask)
{
	NTSTATUS status;

	if (!sd || !sid)
		return NT_STATUS_INVALID_PARAMETER;

	status = sec_ace_mod_sid(sd->dacl->ace, sd->dacl->num_aces, sid, mask);

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

/*******************************************************************
 Delete a SID from a SEC_DESC.
********************************************************************/

NTSTATUS sec_desc_del_sid(TALLOC_CTX *ctx, SEC_DESC **psd, DOM_SID *sid, size_t *sd_size)
{
	SEC_DESC *sd   = 0;
	SEC_ACL  *dacl = 0;
	SEC_ACE  *ace  = 0;
	NTSTATUS  status;

	*sd_size = 0;
	
	if (!ctx || !psd[0] || !sid || !sd_size)
		return NT_STATUS_INVALID_PARAMETER;

	status = sec_ace_del_sid(ctx, &ace, psd[0]->dacl->ace, &psd[0]->dacl->num_aces, sid);

	if (!NT_STATUS_IS_OK(status))
		return status;

	if (!(dacl = make_sec_acl(ctx, psd[0]->dacl->revision, psd[0]->dacl->num_aces, ace)))
		return NT_STATUS_UNSUCCESSFUL;
	
	if (!(sd = make_sec_desc(ctx, psd[0]->revision, psd[0]->type, psd[0]->owner_sid, 
		psd[0]->grp_sid, psd[0]->sacl, dacl, sd_size)))
		return NT_STATUS_UNSUCCESSFUL;

	*psd = sd;
	 sd  = 0;
	return NT_STATUS_OK;
}

/* Create a child security descriptor using another security descriptor as
   the parent container.  This child object can either be a container or
   non-container object. */

SEC_DESC_BUF *se_create_child_secdesc(TALLOC_CTX *ctx, SEC_DESC *parent_ctr, 
				      BOOL child_container)
{
	SEC_DESC_BUF *sdb;
	SEC_DESC *sd;
	SEC_ACL *new_dacl, *the_acl;
	SEC_ACE *new_ace_list = NULL;
	unsigned int new_ace_list_ndx = 0, i;
	size_t size;

	/* Currently we only process the dacl when creating the child.  The
	   sacl should also be processed but this is left out as sacls are
	   not implemented in Samba at the moment.*/

	the_acl = parent_ctr->dacl;

	if (!(new_ace_list = TALLOC_ARRAY(ctx, SEC_ACE, the_acl->num_aces))) 
		return NULL;

	for (i = 0; the_acl && i < the_acl->num_aces; i++) {
		SEC_ACE *ace = &the_acl->ace[i];
		SEC_ACE *new_ace = &new_ace_list[new_ace_list_ndx];
		uint8 new_flags = 0;
		BOOL inherit = False;
		fstring sid_str;

		/* The OBJECT_INHERIT_ACE flag causes the ACE to be
		   inherited by non-container children objects.  Container
		   children objects will inherit it as an INHERIT_ONLY
		   ACE. */

		if (ace->flags & SEC_ACE_FLAG_OBJECT_INHERIT) {

			if (!child_container) {
				new_flags |= SEC_ACE_FLAG_OBJECT_INHERIT;
			} else {
				new_flags |= SEC_ACE_FLAG_INHERIT_ONLY;
			}

			inherit = True;
		}

		/* The CONAINER_INHERIT_ACE flag means all child container
		   objects will inherit and use the ACE. */

		if (ace->flags & SEC_ACE_FLAG_CONTAINER_INHERIT) {
			if (!child_container) {
				inherit = False;
			} else {
				new_flags |= SEC_ACE_FLAG_CONTAINER_INHERIT;
			}
		}

		/* The INHERIT_ONLY_ACE is not used by the se_access_check()
		   function for the parent container, but is inherited by
		   all child objects as a normal ACE. */

		if (ace->flags & SEC_ACE_FLAG_INHERIT_ONLY) {
			/* Move along, nothing to see here */
		}

		/* The SEC_ACE_FLAG_NO_PROPAGATE_INHERIT flag means the ACE
		   is inherited by child objects but not grandchildren
		   objects.  We clear the object inherit and container
		   inherit flags in the inherited ACE. */

		if (ace->flags & SEC_ACE_FLAG_NO_PROPAGATE_INHERIT) {
			new_flags &= ~(SEC_ACE_FLAG_OBJECT_INHERIT |
				       SEC_ACE_FLAG_CONTAINER_INHERIT);
		}

		/* Add ACE to ACE list */

		if (!inherit)
			continue;

		init_sec_access(&new_ace->info, ace->info.mask);
		init_sec_ace(new_ace, &ace->trustee, ace->type,
			     new_ace->info, new_flags);

		sid_to_string(sid_str, &ace->trustee);

		DEBUG(5, ("se_create_child_secdesc(): %s:%d/0x%02x/0x%08x "
			  " inherited as %s:%d/0x%02x/0x%08x\n", sid_str,
			  ace->type, ace->flags, ace->info.mask,
			  sid_str, new_ace->type, new_ace->flags,
			  new_ace->info.mask));

		new_ace_list_ndx++;
	}

	/* Create child security descriptor to return */
	
	new_dacl = make_sec_acl(ctx, ACL_REVISION, new_ace_list_ndx, new_ace_list);

	/* Use the existing user and group sids.  I don't think this is
	   correct.  Perhaps the user and group should be passed in as
	   parameters by the caller? */

	sd = make_sec_desc(ctx, SEC_DESC_REVISION, SEC_DESC_SELF_RELATIVE,
			   parent_ctr->owner_sid,
			   parent_ctr->grp_sid,
			   parent_ctr->sacl,
			   new_dacl, &size);

	sdb = make_sec_desc_buf(ctx, size, sd);

	return sdb;
}

/*******************************************************************
 Sets up a SEC_ACCESS structure.
********************************************************************/

void init_sec_access(SEC_ACCESS *t, uint32 mask)
{
	t->mask = mask;
}