xref: /titanic_41/usr/src/uts/common/fs/zfs/dsl_deleg.c (revision 675fc291908baceb17f92b0b6d961439aaddafc9)
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 (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
23  * Copyright (c) 2011, 2015 by Delphix. All rights reserved.
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
dsl_deleg_can_allow(char * ddname,nvlist_t * nvp,cred_t * cr)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 (SET_ERROR(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
dsl_deleg_can_unallow(char * ddname,nvlist_t * nvp,cred_t * cr)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 (SET_ERROR(EPERM));
143 
144 		if (strcmp(idstr, &nvpair_name(whopair)[3]) != 0)
145 			return (SET_ERROR(EPERM));
146 	}
147 	return (0);
148 }
149 
150 typedef struct dsl_deleg_arg {
151 	const char *dda_name;
152 	nvlist_t *dda_nvlist;
153 } dsl_deleg_arg_t;
154 
155 static void
dsl_deleg_set_sync(void * arg,dmu_tx_t * tx)156 dsl_deleg_set_sync(void *arg, dmu_tx_t *tx)
157 {
158 	dsl_deleg_arg_t *dda = arg;
159 	dsl_dir_t *dd;
160 	dsl_pool_t *dp = dmu_tx_pool(tx);
161 	objset_t *mos = dp->dp_meta_objset;
162 	nvpair_t *whopair = NULL;
163 	uint64_t zapobj;
164 
165 	VERIFY0(dsl_dir_hold(dp, dda->dda_name, FTAG, &dd, NULL));
166 
167 	zapobj = dsl_dir_phys(dd)->dd_deleg_zapobj;
168 	if (zapobj == 0) {
169 		dmu_buf_will_dirty(dd->dd_dbuf, tx);
170 		zapobj = dsl_dir_phys(dd)->dd_deleg_zapobj = zap_create(mos,
171 		    DMU_OT_DSL_PERMS, DMU_OT_NONE, 0, tx);
172 	}
173 
174 	while (whopair = nvlist_next_nvpair(dda->dda_nvlist, whopair)) {
175 		const char *whokey = nvpair_name(whopair);
176 		nvlist_t *perms;
177 		nvpair_t *permpair = NULL;
178 		uint64_t jumpobj;
179 
180 		perms = fnvpair_value_nvlist(whopair);
181 
182 		if (zap_lookup(mos, zapobj, whokey, 8, 1, &jumpobj) != 0) {
183 			jumpobj = zap_create_link(mos, DMU_OT_DSL_PERMS,
184 			    zapobj, whokey, tx);
185 		}
186 
187 		while (permpair = nvlist_next_nvpair(perms, permpair)) {
188 			const char *perm = nvpair_name(permpair);
189 			uint64_t n = 0;
190 
191 			VERIFY(zap_update(mos, jumpobj,
192 			    perm, 8, 1, &n, tx) == 0);
193 			spa_history_log_internal_dd(dd, "permission update", tx,
194 			    "%s %s", whokey, perm);
195 		}
196 	}
197 	dsl_dir_rele(dd, FTAG);
198 }
199 
200 static void
dsl_deleg_unset_sync(void * arg,dmu_tx_t * tx)201 dsl_deleg_unset_sync(void *arg, dmu_tx_t *tx)
202 {
203 	dsl_deleg_arg_t *dda = arg;
204 	dsl_dir_t *dd;
205 	dsl_pool_t *dp = dmu_tx_pool(tx);
206 	objset_t *mos = dp->dp_meta_objset;
207 	nvpair_t *whopair = NULL;
208 	uint64_t zapobj;
209 
210 	VERIFY0(dsl_dir_hold(dp, dda->dda_name, FTAG, &dd, NULL));
211 	zapobj = dsl_dir_phys(dd)->dd_deleg_zapobj;
212 	if (zapobj == 0) {
213 		dsl_dir_rele(dd, FTAG);
214 		return;
215 	}
216 
217 	while (whopair = nvlist_next_nvpair(dda->dda_nvlist, whopair)) {
218 		const char *whokey = nvpair_name(whopair);
219 		nvlist_t *perms;
220 		nvpair_t *permpair = NULL;
221 		uint64_t jumpobj;
222 
223 		if (nvpair_value_nvlist(whopair, &perms) != 0) {
224 			if (zap_lookup(mos, zapobj, whokey, 8,
225 			    1, &jumpobj) == 0) {
226 				(void) zap_remove(mos, zapobj, whokey, tx);
227 				VERIFY(0 == zap_destroy(mos, jumpobj, tx));
228 			}
229 			spa_history_log_internal_dd(dd, "permission who remove",
230 			    tx, "%s", whokey);
231 			continue;
232 		}
233 
234 		if (zap_lookup(mos, zapobj, whokey, 8, 1, &jumpobj) != 0)
235 			continue;
236 
237 		while (permpair = nvlist_next_nvpair(perms, permpair)) {
238 			const char *perm = nvpair_name(permpair);
239 			uint64_t n = 0;
240 
241 			(void) zap_remove(mos, jumpobj, perm, tx);
242 			if (zap_count(mos, jumpobj, &n) == 0 && n == 0) {
243 				(void) zap_remove(mos, zapobj,
244 				    whokey, tx);
245 				VERIFY(0 == zap_destroy(mos,
246 				    jumpobj, tx));
247 			}
248 			spa_history_log_internal_dd(dd, "permission remove", tx,
249 			    "%s %s", whokey, perm);
250 		}
251 	}
252 	dsl_dir_rele(dd, FTAG);
253 }
254 
255 static int
dsl_deleg_check(void * arg,dmu_tx_t * tx)256 dsl_deleg_check(void *arg, dmu_tx_t *tx)
257 {
258 	dsl_deleg_arg_t *dda = arg;
259 	dsl_dir_t *dd;
260 	int error;
261 
262 	if (spa_version(dmu_tx_pool(tx)->dp_spa) <
263 	    SPA_VERSION_DELEGATED_PERMS) {
264 		return (SET_ERROR(ENOTSUP));
265 	}
266 
267 	error = dsl_dir_hold(dmu_tx_pool(tx), dda->dda_name, FTAG, &dd, NULL);
268 	if (error == 0)
269 		dsl_dir_rele(dd, FTAG);
270 	return (error);
271 }
272 
273 int
dsl_deleg_set(const char * ddname,nvlist_t * nvp,boolean_t unset)274 dsl_deleg_set(const char *ddname, nvlist_t *nvp, boolean_t unset)
275 {
276 	dsl_deleg_arg_t dda;
277 
278 	/* nvp must already have been verified to be valid */
279 
280 	dda.dda_name = ddname;
281 	dda.dda_nvlist = nvp;
282 
283 	return (dsl_sync_task(ddname, dsl_deleg_check,
284 	    unset ? dsl_deleg_unset_sync : dsl_deleg_set_sync,
285 	    &dda, fnvlist_num_pairs(nvp), ZFS_SPACE_CHECK_RESERVED));
286 }
287 
288 /*
289  * Find all 'allow' permissions from a given point and then continue
290  * traversing up to the root.
291  *
292  * This function constructs an nvlist of nvlists.
293  * each setpoint is an nvlist composed of an nvlist of an nvlist
294  * of the individual * users/groups/everyone/create
295  * permissions.
296  *
297  * The nvlist will look like this.
298  *
299  * { source fsname -> { whokeys { permissions,...}, ...}}
300  *
301  * The fsname nvpairs will be arranged in a bottom up order.  For example,
302  * if we have the following structure a/b/c then the nvpairs for the fsnames
303  * will be ordered a/b/c, a/b, a.
304  */
305 int
dsl_deleg_get(const char * ddname,nvlist_t ** nvp)306 dsl_deleg_get(const char *ddname, nvlist_t **nvp)
307 {
308 	dsl_dir_t *dd, *startdd;
309 	dsl_pool_t *dp;
310 	int error;
311 	objset_t *mos;
312 
313 	error = dsl_pool_hold(ddname, FTAG, &dp);
314 	if (error != 0)
315 		return (error);
316 
317 	error = dsl_dir_hold(dp, ddname, FTAG, &startdd, NULL);
318 	if (error != 0) {
319 		dsl_pool_rele(dp, FTAG);
320 		return (error);
321 	}
322 
323 	dp = startdd->dd_pool;
324 	mos = dp->dp_meta_objset;
325 
326 	VERIFY(nvlist_alloc(nvp, NV_UNIQUE_NAME, KM_SLEEP) == 0);
327 
328 	for (dd = startdd; dd != NULL; dd = dd->dd_parent) {
329 		zap_cursor_t basezc;
330 		zap_attribute_t baseza;
331 		nvlist_t *sp_nvp;
332 		uint64_t n;
333 		char source[ZFS_MAX_DATASET_NAME_LEN];
334 
335 		if (dsl_dir_phys(dd)->dd_deleg_zapobj == 0 ||
336 		    zap_count(mos,
337 		    dsl_dir_phys(dd)->dd_deleg_zapobj, &n) != 0 || n == 0)
338 			continue;
339 
340 		sp_nvp = fnvlist_alloc();
341 		for (zap_cursor_init(&basezc, mos,
342 		    dsl_dir_phys(dd)->dd_deleg_zapobj);
343 		    zap_cursor_retrieve(&basezc, &baseza) == 0;
344 		    zap_cursor_advance(&basezc)) {
345 			zap_cursor_t zc;
346 			zap_attribute_t za;
347 			nvlist_t *perms_nvp;
348 
349 			ASSERT(baseza.za_integer_length == 8);
350 			ASSERT(baseza.za_num_integers == 1);
351 
352 			perms_nvp = fnvlist_alloc();
353 			for (zap_cursor_init(&zc, mos, baseza.za_first_integer);
354 			    zap_cursor_retrieve(&zc, &za) == 0;
355 			    zap_cursor_advance(&zc)) {
356 				fnvlist_add_boolean(perms_nvp, za.za_name);
357 			}
358 			zap_cursor_fini(&zc);
359 			fnvlist_add_nvlist(sp_nvp, baseza.za_name, perms_nvp);
360 			fnvlist_free(perms_nvp);
361 		}
362 
363 		zap_cursor_fini(&basezc);
364 
365 		dsl_dir_name(dd, source);
366 		fnvlist_add_nvlist(*nvp, source, sp_nvp);
367 		nvlist_free(sp_nvp);
368 	}
369 
370 	dsl_dir_rele(startdd, FTAG);
371 	dsl_pool_rele(dp, FTAG);
372 	return (0);
373 }
374 
375 /*
376  * Routines for dsl_deleg_access() -- access checking.
377  */
378 typedef struct perm_set {
379 	avl_node_t	p_node;
380 	boolean_t	p_matched;
381 	char		p_setname[ZFS_MAX_DELEG_NAME];
382 } perm_set_t;
383 
384 static int
perm_set_compare(const void * arg1,const void * arg2)385 perm_set_compare(const void *arg1, const void *arg2)
386 {
387 	const perm_set_t *node1 = arg1;
388 	const perm_set_t *node2 = arg2;
389 	int val;
390 
391 	val = strcmp(node1->p_setname, node2->p_setname);
392 	if (val == 0)
393 		return (0);
394 	return (val > 0 ? 1 : -1);
395 }
396 
397 /*
398  * Determine whether a specified permission exists.
399  *
400  * First the base attribute has to be retrieved.  i.e. ul$12
401  * Once the base object has been retrieved the actual permission
402  * is lookup up in the zap object the base object points to.
403  *
404  * Return 0 if permission exists, ENOENT if there is no whokey, EPERM if
405  * there is no perm in that jumpobj.
406  */
407 static int
dsl_check_access(objset_t * mos,uint64_t zapobj,char type,char checkflag,void * valp,const char * perm)408 dsl_check_access(objset_t *mos, uint64_t zapobj,
409     char type, char checkflag, void *valp, const char *perm)
410 {
411 	int error;
412 	uint64_t jumpobj, zero;
413 	char whokey[ZFS_MAX_DELEG_NAME];
414 
415 	zfs_deleg_whokey(whokey, type, checkflag, valp);
416 	error = zap_lookup(mos, zapobj, whokey, 8, 1, &jumpobj);
417 	if (error == 0) {
418 		error = zap_lookup(mos, jumpobj, perm, 8, 1, &zero);
419 		if (error == ENOENT)
420 			error = SET_ERROR(EPERM);
421 	}
422 	return (error);
423 }
424 
425 /*
426  * check a specified user/group for a requested permission
427  */
428 static int
dsl_check_user_access(objset_t * mos,uint64_t zapobj,const char * perm,int checkflag,cred_t * cr)429 dsl_check_user_access(objset_t *mos, uint64_t zapobj, const char *perm,
430     int checkflag, cred_t *cr)
431 {
432 	const	gid_t *gids;
433 	int	ngids;
434 	int	i;
435 	uint64_t id;
436 
437 	/* check for user */
438 	id = crgetuid(cr);
439 	if (dsl_check_access(mos, zapobj,
440 	    ZFS_DELEG_USER, checkflag, &id, perm) == 0)
441 		return (0);
442 
443 	/* check for users primary group */
444 	id = crgetgid(cr);
445 	if (dsl_check_access(mos, zapobj,
446 	    ZFS_DELEG_GROUP, checkflag, &id, perm) == 0)
447 		return (0);
448 
449 	/* check for everyone entry */
450 	id = -1;
451 	if (dsl_check_access(mos, zapobj,
452 	    ZFS_DELEG_EVERYONE, checkflag, &id, perm) == 0)
453 		return (0);
454 
455 	/* check each supplemental group user is a member of */
456 	ngids = crgetngroups(cr);
457 	gids = crgetgroups(cr);
458 	for (i = 0; i != ngids; i++) {
459 		id = gids[i];
460 		if (dsl_check_access(mos, zapobj,
461 		    ZFS_DELEG_GROUP, checkflag, &id, perm) == 0)
462 			return (0);
463 	}
464 
465 	return (SET_ERROR(EPERM));
466 }
467 
468 /*
469  * Iterate over the sets specified in the specified zapobj
470  * and load them into the permsets avl tree.
471  */
472 static int
dsl_load_sets(objset_t * mos,uint64_t zapobj,char type,char checkflag,void * valp,avl_tree_t * avl)473 dsl_load_sets(objset_t *mos, uint64_t zapobj,
474     char type, char checkflag, void *valp, avl_tree_t *avl)
475 {
476 	zap_cursor_t zc;
477 	zap_attribute_t za;
478 	perm_set_t *permnode;
479 	avl_index_t idx;
480 	uint64_t jumpobj;
481 	int error;
482 	char whokey[ZFS_MAX_DELEG_NAME];
483 
484 	zfs_deleg_whokey(whokey, type, checkflag, valp);
485 
486 	error = zap_lookup(mos, zapobj, whokey, 8, 1, &jumpobj);
487 	if (error != 0)
488 		return (error);
489 
490 	for (zap_cursor_init(&zc, mos, jumpobj);
491 	    zap_cursor_retrieve(&zc, &za) == 0;
492 	    zap_cursor_advance(&zc)) {
493 		permnode = kmem_alloc(sizeof (perm_set_t), KM_SLEEP);
494 		(void) strlcpy(permnode->p_setname, za.za_name,
495 		    sizeof (permnode->p_setname));
496 		permnode->p_matched = B_FALSE;
497 
498 		if (avl_find(avl, permnode, &idx) == NULL) {
499 			avl_insert(avl, permnode, idx);
500 		} else {
501 			kmem_free(permnode, sizeof (perm_set_t));
502 		}
503 	}
504 	zap_cursor_fini(&zc);
505 	return (0);
506 }
507 
508 /*
509  * Load all permissions user based on cred belongs to.
510  */
511 static void
dsl_load_user_sets(objset_t * mos,uint64_t zapobj,avl_tree_t * avl,char checkflag,cred_t * cr)512 dsl_load_user_sets(objset_t *mos, uint64_t zapobj, avl_tree_t *avl,
513     char checkflag, cred_t *cr)
514 {
515 	const	gid_t *gids;
516 	int	ngids, i;
517 	uint64_t id;
518 
519 	id = crgetuid(cr);
520 	(void) dsl_load_sets(mos, zapobj,
521 	    ZFS_DELEG_USER_SETS, checkflag, &id, avl);
522 
523 	id = crgetgid(cr);
524 	(void) dsl_load_sets(mos, zapobj,
525 	    ZFS_DELEG_GROUP_SETS, checkflag, &id, avl);
526 
527 	(void) dsl_load_sets(mos, zapobj,
528 	    ZFS_DELEG_EVERYONE_SETS, checkflag, NULL, avl);
529 
530 	ngids = crgetngroups(cr);
531 	gids = crgetgroups(cr);
532 	for (i = 0; i != ngids; i++) {
533 		id = gids[i];
534 		(void) dsl_load_sets(mos, zapobj,
535 		    ZFS_DELEG_GROUP_SETS, checkflag, &id, avl);
536 	}
537 }
538 
539 /*
540  * Check if user has requested permission.
541  */
542 int
dsl_deleg_access_impl(dsl_dataset_t * ds,const char * perm,cred_t * cr)543 dsl_deleg_access_impl(dsl_dataset_t *ds, const char *perm, cred_t *cr)
544 {
545 	dsl_dir_t *dd;
546 	dsl_pool_t *dp;
547 	void *cookie;
548 	int	error;
549 	char	checkflag;
550 	objset_t *mos;
551 	avl_tree_t permsets;
552 	perm_set_t *setnode;
553 
554 	dp = ds->ds_dir->dd_pool;
555 	mos = dp->dp_meta_objset;
556 
557 	if (dsl_delegation_on(mos) == B_FALSE)
558 		return (SET_ERROR(ECANCELED));
559 
560 	if (spa_version(dmu_objset_spa(dp->dp_meta_objset)) <
561 	    SPA_VERSION_DELEGATED_PERMS)
562 		return (SET_ERROR(EPERM));
563 
564 	if (ds->ds_is_snapshot) {
565 		/*
566 		 * Snapshots are treated as descendents only,
567 		 * local permissions do not apply.
568 		 */
569 		checkflag = ZFS_DELEG_DESCENDENT;
570 	} else {
571 		checkflag = ZFS_DELEG_LOCAL;
572 	}
573 
574 	avl_create(&permsets, perm_set_compare, sizeof (perm_set_t),
575 	    offsetof(perm_set_t, p_node));
576 
577 	ASSERT(dsl_pool_config_held(dp));
578 	for (dd = ds->ds_dir; dd != NULL; dd = dd->dd_parent,
579 	    checkflag = ZFS_DELEG_DESCENDENT) {
580 		uint64_t zapobj;
581 		boolean_t expanded;
582 
583 		/*
584 		 * If not in global zone then make sure
585 		 * the zoned property is set
586 		 */
587 		if (!INGLOBALZONE(curproc)) {
588 			uint64_t zoned;
589 
590 			if (dsl_prop_get_dd(dd,
591 			    zfs_prop_to_name(ZFS_PROP_ZONED),
592 			    8, 1, &zoned, NULL, B_FALSE) != 0)
593 				break;
594 			if (!zoned)
595 				break;
596 		}
597 		zapobj = dsl_dir_phys(dd)->dd_deleg_zapobj;
598 
599 		if (zapobj == 0)
600 			continue;
601 
602 		dsl_load_user_sets(mos, zapobj, &permsets, checkflag, cr);
603 again:
604 		expanded = B_FALSE;
605 		for (setnode = avl_first(&permsets); setnode;
606 		    setnode = AVL_NEXT(&permsets, setnode)) {
607 			if (setnode->p_matched == B_TRUE)
608 				continue;
609 
610 			/* See if this set directly grants this permission */
611 			error = dsl_check_access(mos, zapobj,
612 			    ZFS_DELEG_NAMED_SET, 0, setnode->p_setname, perm);
613 			if (error == 0)
614 				goto success;
615 			if (error == EPERM)
616 				setnode->p_matched = B_TRUE;
617 
618 			/* See if this set includes other sets */
619 			error = dsl_load_sets(mos, zapobj,
620 			    ZFS_DELEG_NAMED_SET_SETS, 0,
621 			    setnode->p_setname, &permsets);
622 			if (error == 0)
623 				setnode->p_matched = expanded = B_TRUE;
624 		}
625 		/*
626 		 * If we expanded any sets, that will define more sets,
627 		 * which we need to check.
628 		 */
629 		if (expanded)
630 			goto again;
631 
632 		error = dsl_check_user_access(mos, zapobj, perm, checkflag, cr);
633 		if (error == 0)
634 			goto success;
635 	}
636 	error = SET_ERROR(EPERM);
637 success:
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 int
dsl_deleg_access(const char * dsname,const char * perm,cred_t * cr)647 dsl_deleg_access(const char *dsname, const char *perm, cred_t *cr)
648 {
649 	dsl_pool_t *dp;
650 	dsl_dataset_t *ds;
651 	int error;
652 
653 	error = dsl_pool_hold(dsname, FTAG, &dp);
654 	if (error != 0)
655 		return (error);
656 	error = dsl_dataset_hold(dp, dsname, FTAG, &ds);
657 	if (error == 0) {
658 		error = dsl_deleg_access_impl(ds, perm, cr);
659 		dsl_dataset_rele(ds, FTAG);
660 	}
661 	dsl_pool_rele(dp, FTAG);
662 
663 	return (error);
664 }
665 
666 /*
667  * Other routines.
668  */
669 
670 static void
copy_create_perms(dsl_dir_t * dd,uint64_t pzapobj,boolean_t dosets,uint64_t uid,dmu_tx_t * tx)671 copy_create_perms(dsl_dir_t *dd, uint64_t pzapobj,
672     boolean_t dosets, uint64_t uid, dmu_tx_t *tx)
673 {
674 	objset_t *mos = dd->dd_pool->dp_meta_objset;
675 	uint64_t jumpobj, pjumpobj;
676 	uint64_t zapobj = dsl_dir_phys(dd)->dd_deleg_zapobj;
677 	zap_cursor_t zc;
678 	zap_attribute_t za;
679 	char whokey[ZFS_MAX_DELEG_NAME];
680 
681 	zfs_deleg_whokey(whokey,
682 	    dosets ? ZFS_DELEG_CREATE_SETS : ZFS_DELEG_CREATE,
683 	    ZFS_DELEG_LOCAL, NULL);
684 	if (zap_lookup(mos, pzapobj, whokey, 8, 1, &pjumpobj) != 0)
685 		return;
686 
687 	if (zapobj == 0) {
688 		dmu_buf_will_dirty(dd->dd_dbuf, tx);
689 		zapobj = dsl_dir_phys(dd)->dd_deleg_zapobj = zap_create(mos,
690 		    DMU_OT_DSL_PERMS, DMU_OT_NONE, 0, tx);
691 	}
692 
693 	zfs_deleg_whokey(whokey,
694 	    dosets ? ZFS_DELEG_USER_SETS : ZFS_DELEG_USER,
695 	    ZFS_DELEG_LOCAL, &uid);
696 	if (zap_lookup(mos, zapobj, whokey, 8, 1, &jumpobj) == ENOENT) {
697 		jumpobj = zap_create(mos, DMU_OT_DSL_PERMS, DMU_OT_NONE, 0, tx);
698 		VERIFY(zap_add(mos, zapobj, whokey, 8, 1, &jumpobj, tx) == 0);
699 	}
700 
701 	for (zap_cursor_init(&zc, mos, pjumpobj);
702 	    zap_cursor_retrieve(&zc, &za) == 0;
703 	    zap_cursor_advance(&zc)) {
704 		uint64_t zero = 0;
705 		ASSERT(za.za_integer_length == 8 && za.za_num_integers == 1);
706 
707 		VERIFY(zap_update(mos, jumpobj, za.za_name,
708 		    8, 1, &zero, tx) == 0);
709 	}
710 	zap_cursor_fini(&zc);
711 }
712 
713 /*
714  * set all create time permission on new dataset.
715  */
716 void
dsl_deleg_set_create_perms(dsl_dir_t * sdd,dmu_tx_t * tx,cred_t * cr)717 dsl_deleg_set_create_perms(dsl_dir_t *sdd, dmu_tx_t *tx, cred_t *cr)
718 {
719 	dsl_dir_t *dd;
720 	uint64_t uid = crgetuid(cr);
721 
722 	if (spa_version(dmu_objset_spa(sdd->dd_pool->dp_meta_objset)) <
723 	    SPA_VERSION_DELEGATED_PERMS)
724 		return;
725 
726 	for (dd = sdd->dd_parent; dd != NULL; dd = dd->dd_parent) {
727 		uint64_t pzapobj = dsl_dir_phys(dd)->dd_deleg_zapobj;
728 
729 		if (pzapobj == 0)
730 			continue;
731 
732 		copy_create_perms(sdd, pzapobj, B_FALSE, uid, tx);
733 		copy_create_perms(sdd, pzapobj, B_TRUE, uid, tx);
734 	}
735 }
736 
737 int
dsl_deleg_destroy(objset_t * mos,uint64_t zapobj,dmu_tx_t * tx)738 dsl_deleg_destroy(objset_t *mos, uint64_t zapobj, dmu_tx_t *tx)
739 {
740 	zap_cursor_t zc;
741 	zap_attribute_t za;
742 
743 	if (zapobj == 0)
744 		return (0);
745 
746 	for (zap_cursor_init(&zc, mos, zapobj);
747 	    zap_cursor_retrieve(&zc, &za) == 0;
748 	    zap_cursor_advance(&zc)) {
749 		ASSERT(za.za_integer_length == 8 && za.za_num_integers == 1);
750 		VERIFY(0 == zap_destroy(mos, za.za_first_integer, tx));
751 	}
752 	zap_cursor_fini(&zc);
753 	VERIFY(0 == zap_destroy(mos, zapobj, tx));
754 	return (0);
755 }
756 
757 boolean_t
dsl_delegation_on(objset_t * os)758 dsl_delegation_on(objset_t *os)
759 {
760 	return (!!spa_delegation(os->os_spa));
761 }
762