xref: /illumos-gate/usr/src/uts/common/fs/zfs/dsl_deleg.c (revision d616ad8e)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 /*
27  * DSL permissions are stored in a two level zap attribute
28  * mechanism.   The first level identifies the "class" of
29  * entry.  The class is identified by the first 2 letters of
30  * the attribute.  The second letter "l" or "d" identifies whether
31  * it is a local or descendent permission.  The first letter
32  * identifies the type of entry.
33  *
34  * ul$<id>    identifies permissions granted locally for this userid.
35  * ud$<id>    identifies permissions granted on descendent datasets for
36  *            this userid.
37  * Ul$<id>    identifies permission sets granted locally for this userid.
38  * Ud$<id>    identifies permission sets granted on descendent datasets for
39  *            this userid.
40  * gl$<id>    identifies permissions granted locally for this groupid.
41  * gd$<id>    identifies permissions granted on descendent datasets for
42  *            this groupid.
43  * Gl$<id>    identifies permission sets granted locally for this groupid.
44  * Gd$<id>    identifies permission sets granted on descendent datasets for
45  *            this groupid.
46  * el$        identifies permissions granted locally for everyone.
47  * ed$        identifies permissions granted on descendent datasets
48  *            for everyone.
49  * El$        identifies permission sets granted locally for everyone.
50  * Ed$        identifies permission sets granted to descendent datasets for
51  *            everyone.
52  * c-$        identifies permission to create at dataset creation time.
53  * C-$        identifies permission sets to grant locally at dataset creation
54  *            time.
55  * s-$@<name> permissions defined in specified set @<name>
56  * S-$@<name> Sets defined in named set @<name>
57  *
58  * Each of the above entities points to another zap attribute that contains one
59  * attribute for each allowed permission, such as create, destroy,...
60  * All of the "upper" case class types will specify permission set names
61  * rather than permissions.
62  *
63  * Basically it looks something like this:
64  * ul$12 -> ZAP OBJ -> permissions...
65  *
66  * The ZAP OBJ is referred to as the jump object.
67  */
68 
69 #include <sys/dmu.h>
70 #include <sys/dmu_objset.h>
71 #include <sys/dmu_tx.h>
72 #include <sys/dsl_dataset.h>
73 #include <sys/dsl_dir.h>
74 #include <sys/dsl_prop.h>
75 #include <sys/dsl_synctask.h>
76 #include <sys/dsl_deleg.h>
77 #include <sys/spa.h>
78 #include <sys/zap.h>
79 #include <sys/fs/zfs.h>
80 #include <sys/cred.h>
81 #include <sys/sunddi.h>
82 
83 #include "zfs_deleg.h"
84 
85 /*
86  * Validate that user is allowed to delegate specified permissions.
87  *
88  * In order to delegate "create" you must have "create"
89  * and "allow".
90  */
91 int
92 dsl_deleg_can_allow(char *ddname, nvlist_t *nvp, cred_t *cr)
93 {
94 	nvpair_t *whopair = NULL;
95 	int error;
96 
97 	if ((error = dsl_deleg_access(ddname, ZFS_DELEG_PERM_ALLOW, cr)) != 0)
98 		return (error);
99 
100 	while (whopair = nvlist_next_nvpair(nvp, whopair)) {
101 		nvlist_t *perms;
102 		nvpair_t *permpair = NULL;
103 
104 		VERIFY(nvpair_value_nvlist(whopair, &perms) == 0);
105 
106 		while (permpair = nvlist_next_nvpair(perms, permpair)) {
107 			const char *perm = nvpair_name(permpair);
108 
109 			if (strcmp(perm, ZFS_DELEG_PERM_ALLOW) == 0)
110 				return (EPERM);
111 
112 			if ((error = dsl_deleg_access(ddname, perm, cr)) != 0)
113 				return (error);
114 		}
115 	}
116 	return (0);
117 }
118 
119 /*
120  * Validate that user is allowed to unallow specified permissions.  They
121  * must have the 'allow' permission, and even then can only unallow
122  * perms for their uid.
123  */
124 int
125 dsl_deleg_can_unallow(char *ddname, nvlist_t *nvp, cred_t *cr)
126 {
127 	nvpair_t *whopair = NULL;
128 	int error;
129 	char idstr[32];
130 
131 	if ((error = dsl_deleg_access(ddname, ZFS_DELEG_PERM_ALLOW, cr)) != 0)
132 		return (error);
133 
134 	(void) snprintf(idstr, sizeof (idstr), "%lld",
135 	    (longlong_t)crgetuid(cr));
136 
137 	while (whopair = nvlist_next_nvpair(nvp, whopair)) {
138 		zfs_deleg_who_type_t type = nvpair_name(whopair)[0];
139 
140 		if (type != ZFS_DELEG_USER &&
141 		    type != ZFS_DELEG_USER_SETS)
142 			return (EPERM);
143 
144 		if (strcmp(idstr, &nvpair_name(whopair)[3]) != 0)
145 			return (EPERM);
146 	}
147 	return (0);
148 }
149 
150 static void
151 dsl_deleg_set_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx)
152 {
153 	dsl_dir_t *dd = arg1;
154 	nvlist_t *nvp = arg2;
155 	objset_t *mos = dd->dd_pool->dp_meta_objset;
156 	nvpair_t *whopair = NULL;
157 	uint64_t zapobj = dd->dd_phys->dd_deleg_zapobj;
158 
159 	if (zapobj == 0) {
160 		dmu_buf_will_dirty(dd->dd_dbuf, tx);
161 		zapobj = dd->dd_phys->dd_deleg_zapobj = zap_create(mos,
162 		    DMU_OT_DSL_PERMS, DMU_OT_NONE, 0, tx);
163 	}
164 
165 	while (whopair = nvlist_next_nvpair(nvp, whopair)) {
166 		const char *whokey = nvpair_name(whopair);
167 		nvlist_t *perms;
168 		nvpair_t *permpair = NULL;
169 		uint64_t jumpobj;
170 
171 		VERIFY(nvpair_value_nvlist(whopair, &perms) == 0);
172 
173 		if (zap_lookup(mos, zapobj, whokey, 8, 1, &jumpobj) != 0) {
174 			jumpobj = zap_create(mos, DMU_OT_DSL_PERMS,
175 			    DMU_OT_NONE, 0, tx);
176 			VERIFY(zap_update(mos, zapobj,
177 			    whokey, 8, 1, &jumpobj, tx) == 0);
178 		}
179 
180 		while (permpair = nvlist_next_nvpair(perms, permpair)) {
181 			const char *perm = nvpair_name(permpair);
182 			uint64_t n = 0;
183 
184 			VERIFY(zap_update(mos, jumpobj,
185 			    perm, 8, 1, &n, tx) == 0);
186 			spa_history_internal_log(LOG_DS_PERM_UPDATE,
187 			    dd->dd_pool->dp_spa, tx, cr,
188 			    "%s %s dataset = %llu", whokey, perm,
189 			    dd->dd_phys->dd_head_dataset_obj);
190 		}
191 	}
192 }
193 
194 static void
195 dsl_deleg_unset_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx)
196 {
197 	dsl_dir_t *dd = arg1;
198 	nvlist_t *nvp = arg2;
199 	objset_t *mos = dd->dd_pool->dp_meta_objset;
200 	nvpair_t *whopair = NULL;
201 	uint64_t zapobj = dd->dd_phys->dd_deleg_zapobj;
202 
203 	if (zapobj == 0)
204 		return;
205 
206 	while (whopair = nvlist_next_nvpair(nvp, whopair)) {
207 		const char *whokey = nvpair_name(whopair);
208 		nvlist_t *perms;
209 		nvpair_t *permpair = NULL;
210 		uint64_t jumpobj;
211 
212 		if (nvpair_value_nvlist(whopair, &perms) != 0) {
213 			if (zap_lookup(mos, zapobj, whokey, 8,
214 			    1, &jumpobj) == 0) {
215 				(void) zap_remove(mos, zapobj, whokey, tx);
216 				VERIFY(0 == zap_destroy(mos, jumpobj, tx));
217 			}
218 			spa_history_internal_log(LOG_DS_PERM_WHO_REMOVE,
219 			    dd->dd_pool->dp_spa, tx, cr,
220 			    "%s dataset = %llu", whokey,
221 			    dd->dd_phys->dd_head_dataset_obj);
222 			continue;
223 		}
224 
225 		if (zap_lookup(mos, zapobj, whokey, 8, 1, &jumpobj) != 0)
226 			continue;
227 
228 		while (permpair = nvlist_next_nvpair(perms, permpair)) {
229 			const char *perm = nvpair_name(permpair);
230 			uint64_t n = 0;
231 
232 			(void) zap_remove(mos, jumpobj, perm, tx);
233 			if (zap_count(mos, jumpobj, &n) == 0 && n == 0) {
234 				(void) zap_remove(mos, zapobj,
235 				    whokey, tx);
236 				VERIFY(0 == zap_destroy(mos,
237 				    jumpobj, tx));
238 			}
239 			spa_history_internal_log(LOG_DS_PERM_REMOVE,
240 			    dd->dd_pool->dp_spa, tx, cr,
241 			    "%s %s dataset = %llu", whokey, perm,
242 			    dd->dd_phys->dd_head_dataset_obj);
243 		}
244 	}
245 }
246 
247 int
248 dsl_deleg_set(const char *ddname, nvlist_t *nvp, boolean_t unset)
249 {
250 	dsl_dir_t *dd;
251 	int error;
252 	nvpair_t *whopair = NULL;
253 	int blocks_modified = 0;
254 
255 	error = dsl_dir_open(ddname, FTAG, &dd, NULL);
256 	if (error)
257 		return (error);
258 
259 	if (spa_version(dmu_objset_spa(dd->dd_pool->dp_meta_objset)) <
260 	    SPA_VERSION_DELEGATED_PERMS) {
261 		dsl_dir_close(dd, FTAG);
262 		return (ENOTSUP);
263 	}
264 
265 	while (whopair = nvlist_next_nvpair(nvp, whopair))
266 		blocks_modified++;
267 
268 	error = dsl_sync_task_do(dd->dd_pool, NULL,
269 	    unset ? dsl_deleg_unset_sync : dsl_deleg_set_sync,
270 	    dd, nvp, blocks_modified);
271 	dsl_dir_close(dd, FTAG);
272 
273 	return (error);
274 }
275 
276 /*
277  * Find all 'allow' permissions from a given point and then continue
278  * traversing up to the root.
279  *
280  * This function constructs an nvlist of nvlists.
281  * each setpoint is an nvlist composed of an nvlist of an nvlist
282  * of the individual * users/groups/everyone/create
283  * permissions.
284  *
285  * The nvlist will look like this.
286  *
287  * { source fsname -> { whokeys { permissions,...}, ...}}
288  *
289  * The fsname nvpairs will be arranged in a bottom up order.  For example,
290  * if we have the following structure a/b/c then the nvpairs for the fsnames
291  * will be ordered a/b/c, a/b, a.
292  */
293 int
294 dsl_deleg_get(const char *ddname, nvlist_t **nvp)
295 {
296 	dsl_dir_t *dd, *startdd;
297 	dsl_pool_t *dp;
298 	int error;
299 	objset_t *mos;
300 
301 	error = dsl_dir_open(ddname, FTAG, &startdd, NULL);
302 	if (error)
303 		return (error);
304 
305 	dp = startdd->dd_pool;
306 	mos = dp->dp_meta_objset;
307 
308 	VERIFY(nvlist_alloc(nvp, NV_UNIQUE_NAME, KM_SLEEP) == 0);
309 
310 	rw_enter(&dp->dp_config_rwlock, RW_READER);
311 	for (dd = startdd; dd != NULL; dd = dd->dd_parent) {
312 		zap_cursor_t basezc;
313 		zap_attribute_t baseza;
314 		nvlist_t *sp_nvp;
315 		uint64_t n;
316 		char source[MAXNAMELEN];
317 
318 		if (dd->dd_phys->dd_deleg_zapobj &&
319 		    (zap_count(mos, dd->dd_phys->dd_deleg_zapobj,
320 		    &n) == 0) && n) {
321 			VERIFY(nvlist_alloc(&sp_nvp,
322 			    NV_UNIQUE_NAME, KM_SLEEP) == 0);
323 		} else {
324 			continue;
325 		}
326 
327 		for (zap_cursor_init(&basezc, mos,
328 		    dd->dd_phys->dd_deleg_zapobj);
329 		    zap_cursor_retrieve(&basezc, &baseza) == 0;
330 		    zap_cursor_advance(&basezc)) {
331 			zap_cursor_t zc;
332 			zap_attribute_t za;
333 			nvlist_t *perms_nvp;
334 
335 			ASSERT(baseza.za_integer_length == 8);
336 			ASSERT(baseza.za_num_integers == 1);
337 
338 			VERIFY(nvlist_alloc(&perms_nvp,
339 			    NV_UNIQUE_NAME, KM_SLEEP) == 0);
340 			for (zap_cursor_init(&zc, mos, baseza.za_first_integer);
341 			    zap_cursor_retrieve(&zc, &za) == 0;
342 			    zap_cursor_advance(&zc)) {
343 				VERIFY(nvlist_add_boolean(perms_nvp,
344 				    za.za_name) == 0);
345 			}
346 			zap_cursor_fini(&zc);
347 			VERIFY(nvlist_add_nvlist(sp_nvp, baseza.za_name,
348 			    perms_nvp) == 0);
349 			nvlist_free(perms_nvp);
350 		}
351 
352 		zap_cursor_fini(&basezc);
353 
354 		dsl_dir_name(dd, source);
355 		VERIFY(nvlist_add_nvlist(*nvp, source, sp_nvp) == 0);
356 		nvlist_free(sp_nvp);
357 	}
358 	rw_exit(&dp->dp_config_rwlock);
359 
360 	dsl_dir_close(startdd, FTAG);
361 	return (0);
362 }
363 
364 /*
365  * Routines for dsl_deleg_access() -- access checking.
366  */
367 typedef struct perm_set {
368 	avl_node_t	p_node;
369 	boolean_t	p_matched;
370 	char		p_setname[ZFS_MAX_DELEG_NAME];
371 } perm_set_t;
372 
373 static int
374 perm_set_compare(const void *arg1, const void *arg2)
375 {
376 	const perm_set_t *node1 = arg1;
377 	const perm_set_t *node2 = arg2;
378 	int val;
379 
380 	val = strcmp(node1->p_setname, node2->p_setname);
381 	if (val == 0)
382 		return (0);
383 	return (val > 0 ? 1 : -1);
384 }
385 
386 /*
387  * Determine whether a specified permission exists.
388  *
389  * First the base attribute has to be retrieved.  i.e. ul$12
390  * Once the base object has been retrieved the actual permission
391  * is lookup up in the zap object the base object points to.
392  *
393  * Return 0 if permission exists, ENOENT if there is no whokey, EPERM if
394  * there is no perm in that jumpobj.
395  */
396 static int
397 dsl_check_access(objset_t *mos, uint64_t zapobj,
398     char type, char checkflag, void *valp, const char *perm)
399 {
400 	int error;
401 	uint64_t jumpobj, zero;
402 	char whokey[ZFS_MAX_DELEG_NAME];
403 
404 	zfs_deleg_whokey(whokey, type, checkflag, valp);
405 	error = zap_lookup(mos, zapobj, whokey, 8, 1, &jumpobj);
406 	if (error == 0) {
407 		error = zap_lookup(mos, jumpobj, perm, 8, 1, &zero);
408 		if (error == ENOENT)
409 			error = EPERM;
410 	}
411 	return (error);
412 }
413 
414 /*
415  * check a specified user/group for a requested permission
416  */
417 static int
418 dsl_check_user_access(objset_t *mos, uint64_t zapobj, const char *perm,
419     int checkflag, cred_t *cr)
420 {
421 	const	gid_t *gids;
422 	int	ngids;
423 	int	i;
424 	uint64_t id;
425 
426 	/* check for user */
427 	id = crgetuid(cr);
428 	if (dsl_check_access(mos, zapobj,
429 	    ZFS_DELEG_USER, checkflag, &id, perm) == 0)
430 		return (0);
431 
432 	/* check for users primary group */
433 	id = crgetgid(cr);
434 	if (dsl_check_access(mos, zapobj,
435 	    ZFS_DELEG_GROUP, checkflag, &id, perm) == 0)
436 		return (0);
437 
438 	/* check for everyone entry */
439 	id = -1;
440 	if (dsl_check_access(mos, zapobj,
441 	    ZFS_DELEG_EVERYONE, checkflag, &id, perm) == 0)
442 		return (0);
443 
444 	/* check each supplemental group user is a member of */
445 	ngids = crgetngroups(cr);
446 	gids = crgetgroups(cr);
447 	for (i = 0; i != ngids; i++) {
448 		id = gids[i];
449 		if (dsl_check_access(mos, zapobj,
450 		    ZFS_DELEG_GROUP, checkflag, &id, perm) == 0)
451 			return (0);
452 	}
453 
454 	return (EPERM);
455 }
456 
457 /*
458  * Iterate over the sets specified in the specified zapobj
459  * and load them into the permsets avl tree.
460  */
461 static int
462 dsl_load_sets(objset_t *mos, uint64_t zapobj,
463     char type, char checkflag, void *valp, avl_tree_t *avl)
464 {
465 	zap_cursor_t zc;
466 	zap_attribute_t za;
467 	perm_set_t *permnode;
468 	avl_index_t idx;
469 	uint64_t jumpobj;
470 	int error;
471 	char whokey[ZFS_MAX_DELEG_NAME];
472 
473 	zfs_deleg_whokey(whokey, type, checkflag, valp);
474 
475 	error = zap_lookup(mos, zapobj, whokey, 8, 1, &jumpobj);
476 	if (error != 0)
477 		return (error);
478 
479 	for (zap_cursor_init(&zc, mos, jumpobj);
480 	    zap_cursor_retrieve(&zc, &za) == 0;
481 	    zap_cursor_advance(&zc)) {
482 		permnode = kmem_alloc(sizeof (perm_set_t), KM_SLEEP);
483 		(void) strlcpy(permnode->p_setname, za.za_name,
484 		    sizeof (permnode->p_setname));
485 		permnode->p_matched = B_FALSE;
486 
487 		if (avl_find(avl, permnode, &idx) == NULL) {
488 			avl_insert(avl, permnode, idx);
489 		} else {
490 			kmem_free(permnode, sizeof (perm_set_t));
491 		}
492 	}
493 	zap_cursor_fini(&zc);
494 	return (0);
495 }
496 
497 /*
498  * Load all permissions user based on cred belongs to.
499  */
500 static void
501 dsl_load_user_sets(objset_t *mos, uint64_t zapobj, avl_tree_t *avl,
502     char checkflag, cred_t *cr)
503 {
504 	const	gid_t *gids;
505 	int	ngids, i;
506 	uint64_t id;
507 
508 	id = crgetuid(cr);
509 	(void) dsl_load_sets(mos, zapobj,
510 	    ZFS_DELEG_USER_SETS, checkflag, &id, avl);
511 
512 	id = crgetgid(cr);
513 	(void) dsl_load_sets(mos, zapobj,
514 	    ZFS_DELEG_GROUP_SETS, checkflag, &id, avl);
515 
516 	(void) dsl_load_sets(mos, zapobj,
517 	    ZFS_DELEG_EVERYONE_SETS, checkflag, NULL, avl);
518 
519 	ngids = crgetngroups(cr);
520 	gids = crgetgroups(cr);
521 	for (i = 0; i != ngids; i++) {
522 		id = gids[i];
523 		(void) dsl_load_sets(mos, zapobj,
524 		    ZFS_DELEG_GROUP_SETS, checkflag, &id, avl);
525 	}
526 }
527 
528 /*
529  * Check if user has requested permission.
530  */
531 int
532 dsl_deleg_access(const char *dsname, const char *perm, cred_t *cr)
533 {
534 	dsl_dataset_t *ds;
535 	dsl_dir_t *dd;
536 	dsl_pool_t *dp;
537 	void *cookie;
538 	int	error;
539 	char	checkflag;
540 	objset_t *mos;
541 	avl_tree_t permsets;
542 	perm_set_t *setnode;
543 
544 	error = dsl_dataset_hold(dsname, FTAG, &ds);
545 	if (error)
546 		return (error);
547 
548 	dp = ds->ds_dir->dd_pool;
549 	mos = dp->dp_meta_objset;
550 
551 	if (dsl_delegation_on(mos) == B_FALSE) {
552 		dsl_dataset_rele(ds, FTAG);
553 		return (ECANCELED);
554 	}
555 
556 	if (spa_version(dmu_objset_spa(dp->dp_meta_objset)) <
557 	    SPA_VERSION_DELEGATED_PERMS) {
558 		dsl_dataset_rele(ds, FTAG);
559 		return (EPERM);
560 	}
561 
562 	if (dsl_dataset_is_snapshot(ds)) {
563 		/*
564 		 * Snapshots are treated as descendents only,
565 		 * local permissions do not apply.
566 		 */
567 		checkflag = ZFS_DELEG_DESCENDENT;
568 	} else {
569 		checkflag = ZFS_DELEG_LOCAL;
570 	}
571 
572 	avl_create(&permsets, perm_set_compare, sizeof (perm_set_t),
573 	    offsetof(perm_set_t, p_node));
574 
575 	rw_enter(&dp->dp_config_rwlock, RW_READER);
576 	for (dd = ds->ds_dir; dd != NULL; dd = dd->dd_parent,
577 	    checkflag = ZFS_DELEG_DESCENDENT) {
578 		uint64_t zapobj;
579 		boolean_t expanded;
580 
581 		/*
582 		 * If not in global zone then make sure
583 		 * the zoned property is set
584 		 */
585 		if (!INGLOBALZONE(curproc)) {
586 			uint64_t zoned;
587 
588 			if (dsl_prop_get_dd(dd,
589 			    zfs_prop_to_name(ZFS_PROP_ZONED),
590 			    8, 1, &zoned, NULL) != 0)
591 				break;
592 			if (!zoned)
593 				break;
594 		}
595 		zapobj = dd->dd_phys->dd_deleg_zapobj;
596 
597 		if (zapobj == 0)
598 			continue;
599 
600 		dsl_load_user_sets(mos, zapobj, &permsets, checkflag, cr);
601 again:
602 		expanded = B_FALSE;
603 		for (setnode = avl_first(&permsets); setnode;
604 		    setnode = AVL_NEXT(&permsets, setnode)) {
605 			if (setnode->p_matched == B_TRUE)
606 				continue;
607 
608 			/* See if this set directly grants this permission */
609 			error = dsl_check_access(mos, zapobj,
610 			    ZFS_DELEG_NAMED_SET, 0, setnode->p_setname, perm);
611 			if (error == 0)
612 				goto success;
613 			if (error == EPERM)
614 				setnode->p_matched = B_TRUE;
615 
616 			/* See if this set includes other sets */
617 			error = dsl_load_sets(mos, zapobj,
618 			    ZFS_DELEG_NAMED_SET_SETS, 0,
619 			    setnode->p_setname, &permsets);
620 			if (error == 0)
621 				setnode->p_matched = expanded = B_TRUE;
622 		}
623 		/*
624 		 * If we expanded any sets, that will define more sets,
625 		 * which we need to check.
626 		 */
627 		if (expanded)
628 			goto again;
629 
630 		error = dsl_check_user_access(mos, zapobj, perm, checkflag, cr);
631 		if (error == 0)
632 			goto success;
633 	}
634 	error = EPERM;
635 success:
636 	rw_exit(&dp->dp_config_rwlock);
637 	dsl_dataset_rele(ds, FTAG);
638 
639 	cookie = NULL;
640 	while ((setnode = avl_destroy_nodes(&permsets, &cookie)) != NULL)
641 		kmem_free(setnode, sizeof (perm_set_t));
642 
643 	return (error);
644 }
645 
646 /*
647  * Other routines.
648  */
649 
650 static void
651 copy_create_perms(dsl_dir_t *dd, uint64_t pzapobj,
652     boolean_t dosets, uint64_t uid, dmu_tx_t *tx)
653 {
654 	objset_t *mos = dd->dd_pool->dp_meta_objset;
655 	uint64_t jumpobj, pjumpobj;
656 	uint64_t zapobj = dd->dd_phys->dd_deleg_zapobj;
657 	zap_cursor_t zc;
658 	zap_attribute_t za;
659 	char whokey[ZFS_MAX_DELEG_NAME];
660 
661 	zfs_deleg_whokey(whokey,
662 	    dosets ? ZFS_DELEG_CREATE_SETS : ZFS_DELEG_CREATE,
663 	    ZFS_DELEG_LOCAL, NULL);
664 	if (zap_lookup(mos, pzapobj, whokey, 8, 1, &pjumpobj) != 0)
665 		return;
666 
667 	if (zapobj == 0) {
668 		dmu_buf_will_dirty(dd->dd_dbuf, tx);
669 		zapobj = dd->dd_phys->dd_deleg_zapobj = zap_create(mos,
670 		    DMU_OT_DSL_PERMS, DMU_OT_NONE, 0, tx);
671 	}
672 
673 	zfs_deleg_whokey(whokey,
674 	    dosets ? ZFS_DELEG_USER_SETS : ZFS_DELEG_USER,
675 	    ZFS_DELEG_LOCAL, &uid);
676 	if (zap_lookup(mos, zapobj, whokey, 8, 1, &jumpobj) == ENOENT) {
677 		jumpobj = zap_create(mos, DMU_OT_DSL_PERMS, DMU_OT_NONE, 0, tx);
678 		VERIFY(zap_add(mos, zapobj, whokey, 8, 1, &jumpobj, tx) == 0);
679 	}
680 
681 	for (zap_cursor_init(&zc, mos, pjumpobj);
682 	    zap_cursor_retrieve(&zc, &za) == 0;
683 	    zap_cursor_advance(&zc)) {
684 		uint64_t zero = 0;
685 		ASSERT(za.za_integer_length == 8 && za.za_num_integers == 1);
686 
687 		VERIFY(zap_update(mos, jumpobj, za.za_name,
688 		    8, 1, &zero, tx) == 0);
689 	}
690 	zap_cursor_fini(&zc);
691 }
692 
693 /*
694  * set all create time permission on new dataset.
695  */
696 void
697 dsl_deleg_set_create_perms(dsl_dir_t *sdd, dmu_tx_t *tx, cred_t *cr)
698 {
699 	dsl_dir_t *dd;
700 	uint64_t uid = crgetuid(cr);
701 
702 	if (spa_version(dmu_objset_spa(sdd->dd_pool->dp_meta_objset)) <
703 	    SPA_VERSION_DELEGATED_PERMS)
704 		return;
705 
706 	for (dd = sdd->dd_parent; dd != NULL; dd = dd->dd_parent) {
707 		uint64_t pzapobj = dd->dd_phys->dd_deleg_zapobj;
708 
709 		if (pzapobj == 0)
710 			continue;
711 
712 		copy_create_perms(sdd, pzapobj, B_FALSE, uid, tx);
713 		copy_create_perms(sdd, pzapobj, B_TRUE, uid, tx);
714 	}
715 }
716 
717 int
718 dsl_deleg_destroy(objset_t *mos, uint64_t zapobj, dmu_tx_t *tx)
719 {
720 	zap_cursor_t zc;
721 	zap_attribute_t za;
722 
723 	if (zapobj == 0)
724 		return (0);
725 
726 	for (zap_cursor_init(&zc, mos, zapobj);
727 	    zap_cursor_retrieve(&zc, &za) == 0;
728 	    zap_cursor_advance(&zc)) {
729 		ASSERT(za.za_integer_length == 8 && za.za_num_integers == 1);
730 		VERIFY(0 == zap_destroy(mos, za.za_first_integer, tx));
731 	}
732 	zap_cursor_fini(&zc);
733 	VERIFY(0 == zap_destroy(mos, zapobj, tx));
734 	return (0);
735 }
736 
737 boolean_t
738 dsl_delegation_on(objset_t *os)
739 {
740 	return (!!spa_delegation(os->os_spa));
741 }
742