xref: /illumos-gate/usr/src/uts/common/fs/zfs/dsl_deleg.c (revision 4d7988d6050abba5c1ff60e7fd196e95c22e20f4)
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 = (const perm_set_t *)arg1;
388 	const perm_set_t *node2 = (const perm_set_t *)arg2;
389 	int val;
390 
391 	val = strcmp(node1->p_setname, node2->p_setname);
392 
393 	return (TREE_ISIGN(val));
394 }
395 
396 /*
397  * Determine whether a specified permission exists.
398  *
399  * First the base attribute has to be retrieved.  i.e. ul$12
400  * Once the base object has been retrieved the actual permission
401  * is lookup up in the zap object the base object points to.
402  *
403  * Return 0 if permission exists, ENOENT if there is no whokey, EPERM if
404  * there is no perm in that jumpobj.
405  */
406 static int
dsl_check_access(objset_t * mos,uint64_t zapobj,char type,char checkflag,void * valp,const char * perm)407 dsl_check_access(objset_t *mos, uint64_t zapobj,
408     char type, char checkflag, void *valp, const char *perm)
409 {
410 	int error;
411 	uint64_t jumpobj, zero;
412 	char whokey[ZFS_MAX_DELEG_NAME];
413 
414 	zfs_deleg_whokey(whokey, type, checkflag, valp);
415 	error = zap_lookup(mos, zapobj, whokey, 8, 1, &jumpobj);
416 	if (error == 0) {
417 		error = zap_lookup(mos, jumpobj, perm, 8, 1, &zero);
418 		if (error == ENOENT)
419 			error = SET_ERROR(EPERM);
420 	}
421 	return (error);
422 }
423 
424 /*
425  * check a specified user/group for a requested permission
426  */
427 static int
dsl_check_user_access(objset_t * mos,uint64_t zapobj,const char * perm,int checkflag,cred_t * cr)428 dsl_check_user_access(objset_t *mos, uint64_t zapobj, const char *perm,
429     int checkflag, cred_t *cr)
430 {
431 	const	gid_t *gids;
432 	int	ngids;
433 	int	i;
434 	uint64_t id;
435 
436 	/* check for user */
437 	id = crgetuid(cr);
438 	if (dsl_check_access(mos, zapobj,
439 	    ZFS_DELEG_USER, checkflag, &id, perm) == 0)
440 		return (0);
441 
442 	/* check for users primary group */
443 	id = crgetgid(cr);
444 	if (dsl_check_access(mos, zapobj,
445 	    ZFS_DELEG_GROUP, checkflag, &id, perm) == 0)
446 		return (0);
447 
448 	/* check for everyone entry */
449 	id = -1;
450 	if (dsl_check_access(mos, zapobj,
451 	    ZFS_DELEG_EVERYONE, checkflag, &id, perm) == 0)
452 		return (0);
453 
454 	/* check each supplemental group user is a member of */
455 	ngids = crgetngroups(cr);
456 	gids = crgetgroups(cr);
457 	for (i = 0; i != ngids; i++) {
458 		id = gids[i];
459 		if (dsl_check_access(mos, zapobj,
460 		    ZFS_DELEG_GROUP, checkflag, &id, perm) == 0)
461 			return (0);
462 	}
463 
464 	return (SET_ERROR(EPERM));
465 }
466 
467 /*
468  * Iterate over the sets specified in the specified zapobj
469  * and load them into the permsets avl tree.
470  */
471 static int
dsl_load_sets(objset_t * mos,uint64_t zapobj,char type,char checkflag,void * valp,avl_tree_t * avl)472 dsl_load_sets(objset_t *mos, uint64_t zapobj,
473     char type, char checkflag, void *valp, avl_tree_t *avl)
474 {
475 	zap_cursor_t zc;
476 	zap_attribute_t za;
477 	perm_set_t *permnode;
478 	avl_index_t idx;
479 	uint64_t jumpobj;
480 	int error;
481 	char whokey[ZFS_MAX_DELEG_NAME];
482 
483 	zfs_deleg_whokey(whokey, type, checkflag, valp);
484 
485 	error = zap_lookup(mos, zapobj, whokey, 8, 1, &jumpobj);
486 	if (error != 0)
487 		return (error);
488 
489 	for (zap_cursor_init(&zc, mos, jumpobj);
490 	    zap_cursor_retrieve(&zc, &za) == 0;
491 	    zap_cursor_advance(&zc)) {
492 		permnode = kmem_alloc(sizeof (perm_set_t), KM_SLEEP);
493 		(void) strlcpy(permnode->p_setname, za.za_name,
494 		    sizeof (permnode->p_setname));
495 		permnode->p_matched = B_FALSE;
496 
497 		if (avl_find(avl, permnode, &idx) == NULL) {
498 			avl_insert(avl, permnode, idx);
499 		} else {
500 			kmem_free(permnode, sizeof (perm_set_t));
501 		}
502 	}
503 	zap_cursor_fini(&zc);
504 	return (0);
505 }
506 
507 /*
508  * Load all permissions user based on cred belongs to.
509  */
510 static void
dsl_load_user_sets(objset_t * mos,uint64_t zapobj,avl_tree_t * avl,char checkflag,cred_t * cr)511 dsl_load_user_sets(objset_t *mos, uint64_t zapobj, avl_tree_t *avl,
512     char checkflag, cred_t *cr)
513 {
514 	const	gid_t *gids;
515 	int	ngids, i;
516 	uint64_t id;
517 
518 	id = crgetuid(cr);
519 	(void) dsl_load_sets(mos, zapobj,
520 	    ZFS_DELEG_USER_SETS, checkflag, &id, avl);
521 
522 	id = crgetgid(cr);
523 	(void) dsl_load_sets(mos, zapobj,
524 	    ZFS_DELEG_GROUP_SETS, checkflag, &id, avl);
525 
526 	(void) dsl_load_sets(mos, zapobj,
527 	    ZFS_DELEG_EVERYONE_SETS, checkflag, NULL, avl);
528 
529 	ngids = crgetngroups(cr);
530 	gids = crgetgroups(cr);
531 	for (i = 0; i != ngids; i++) {
532 		id = gids[i];
533 		(void) dsl_load_sets(mos, zapobj,
534 		    ZFS_DELEG_GROUP_SETS, checkflag, &id, avl);
535 	}
536 }
537 
538 /*
539  * Check if user has requested permission.
540  */
541 int
dsl_deleg_access_impl(dsl_dataset_t * ds,const char * perm,cred_t * cr)542 dsl_deleg_access_impl(dsl_dataset_t *ds, const char *perm, cred_t *cr)
543 {
544 	dsl_dir_t *dd;
545 	dsl_pool_t *dp;
546 	void *cookie;
547 	int	error;
548 	char	checkflag;
549 	objset_t *mos;
550 	avl_tree_t permsets;
551 	perm_set_t *setnode;
552 
553 	dp = ds->ds_dir->dd_pool;
554 	mos = dp->dp_meta_objset;
555 
556 	if (dsl_delegation_on(mos) == B_FALSE)
557 		return (SET_ERROR(ECANCELED));
558 
559 	if (spa_version(dmu_objset_spa(dp->dp_meta_objset)) <
560 	    SPA_VERSION_DELEGATED_PERMS)
561 		return (SET_ERROR(EPERM));
562 
563 	if (ds->ds_is_snapshot) {
564 		/*
565 		 * Snapshots are treated as descendents only,
566 		 * local permissions do not apply.
567 		 */
568 		checkflag = ZFS_DELEG_DESCENDENT;
569 	} else {
570 		checkflag = ZFS_DELEG_LOCAL;
571 	}
572 
573 	avl_create(&permsets, perm_set_compare, sizeof (perm_set_t),
574 	    offsetof(perm_set_t, p_node));
575 
576 	ASSERT(dsl_pool_config_held(dp));
577 	for (dd = ds->ds_dir; dd != NULL; dd = dd->dd_parent,
578 	    checkflag = ZFS_DELEG_DESCENDENT) {
579 		uint64_t zapobj;
580 		boolean_t expanded;
581 
582 		/*
583 		 * If not in global zone then make sure
584 		 * the zoned property is set
585 		 */
586 		if (!INGLOBALZONE(curproc)) {
587 			uint64_t zoned;
588 
589 			if (dsl_prop_get_dd(dd,
590 			    zfs_prop_to_name(ZFS_PROP_ZONED),
591 			    8, 1, &zoned, NULL, B_FALSE) != 0)
592 				break;
593 			if (!zoned)
594 				break;
595 		}
596 		zapobj = dsl_dir_phys(dd)->dd_deleg_zapobj;
597 
598 		if (zapobj == 0)
599 			continue;
600 
601 		dsl_load_user_sets(mos, zapobj, &permsets, checkflag, cr);
602 again:
603 		expanded = B_FALSE;
604 		for (setnode = avl_first(&permsets); setnode;
605 		    setnode = AVL_NEXT(&permsets, setnode)) {
606 			if (setnode->p_matched == B_TRUE)
607 				continue;
608 
609 			/* See if this set directly grants this permission */
610 			error = dsl_check_access(mos, zapobj,
611 			    ZFS_DELEG_NAMED_SET, 0, setnode->p_setname, perm);
612 			if (error == 0)
613 				goto success;
614 			if (error == EPERM)
615 				setnode->p_matched = B_TRUE;
616 
617 			/* See if this set includes other sets */
618 			error = dsl_load_sets(mos, zapobj,
619 			    ZFS_DELEG_NAMED_SET_SETS, 0,
620 			    setnode->p_setname, &permsets);
621 			if (error == 0)
622 				setnode->p_matched = expanded = B_TRUE;
623 		}
624 		/*
625 		 * If we expanded any sets, that will define more sets,
626 		 * which we need to check.
627 		 */
628 		if (expanded)
629 			goto again;
630 
631 		error = dsl_check_user_access(mos, zapobj, perm, checkflag, cr);
632 		if (error == 0)
633 			goto success;
634 	}
635 	error = SET_ERROR(EPERM);
636 success:
637 
638 	cookie = NULL;
639 	while ((setnode = avl_destroy_nodes(&permsets, &cookie)) != NULL)
640 		kmem_free(setnode, sizeof (perm_set_t));
641 
642 	return (error);
643 }
644 
645 int
dsl_deleg_access(const char * dsname,const char * perm,cred_t * cr)646 dsl_deleg_access(const char *dsname, const char *perm, cred_t *cr)
647 {
648 	dsl_pool_t *dp;
649 	dsl_dataset_t *ds;
650 	int error;
651 
652 	error = dsl_pool_hold(dsname, FTAG, &dp);
653 	if (error != 0)
654 		return (error);
655 	error = dsl_dataset_hold(dp, dsname, FTAG, &ds);
656 	if (error == 0) {
657 		error = dsl_deleg_access_impl(ds, perm, cr);
658 		dsl_dataset_rele(ds, FTAG);
659 	}
660 	dsl_pool_rele(dp, FTAG);
661 
662 	return (error);
663 }
664 
665 /*
666  * Other routines.
667  */
668 
669 static void
copy_create_perms(dsl_dir_t * dd,uint64_t pzapobj,boolean_t dosets,uint64_t uid,dmu_tx_t * tx)670 copy_create_perms(dsl_dir_t *dd, uint64_t pzapobj,
671     boolean_t dosets, uint64_t uid, dmu_tx_t *tx)
672 {
673 	objset_t *mos = dd->dd_pool->dp_meta_objset;
674 	uint64_t jumpobj, pjumpobj;
675 	uint64_t zapobj = dsl_dir_phys(dd)->dd_deleg_zapobj;
676 	zap_cursor_t zc;
677 	zap_attribute_t za;
678 	char whokey[ZFS_MAX_DELEG_NAME];
679 
680 	zfs_deleg_whokey(whokey,
681 	    dosets ? ZFS_DELEG_CREATE_SETS : ZFS_DELEG_CREATE,
682 	    ZFS_DELEG_LOCAL, NULL);
683 	if (zap_lookup(mos, pzapobj, whokey, 8, 1, &pjumpobj) != 0)
684 		return;
685 
686 	if (zapobj == 0) {
687 		dmu_buf_will_dirty(dd->dd_dbuf, tx);
688 		zapobj = dsl_dir_phys(dd)->dd_deleg_zapobj = zap_create(mos,
689 		    DMU_OT_DSL_PERMS, DMU_OT_NONE, 0, tx);
690 	}
691 
692 	zfs_deleg_whokey(whokey,
693 	    dosets ? ZFS_DELEG_USER_SETS : ZFS_DELEG_USER,
694 	    ZFS_DELEG_LOCAL, &uid);
695 	if (zap_lookup(mos, zapobj, whokey, 8, 1, &jumpobj) == ENOENT) {
696 		jumpobj = zap_create(mos, DMU_OT_DSL_PERMS, DMU_OT_NONE, 0, tx);
697 		VERIFY(zap_add(mos, zapobj, whokey, 8, 1, &jumpobj, tx) == 0);
698 	}
699 
700 	for (zap_cursor_init(&zc, mos, pjumpobj);
701 	    zap_cursor_retrieve(&zc, &za) == 0;
702 	    zap_cursor_advance(&zc)) {
703 		uint64_t zero = 0;
704 		ASSERT(za.za_integer_length == 8 && za.za_num_integers == 1);
705 
706 		VERIFY(zap_update(mos, jumpobj, za.za_name,
707 		    8, 1, &zero, tx) == 0);
708 	}
709 	zap_cursor_fini(&zc);
710 }
711 
712 /*
713  * set all create time permission on new dataset.
714  */
715 void
dsl_deleg_set_create_perms(dsl_dir_t * sdd,dmu_tx_t * tx,cred_t * cr)716 dsl_deleg_set_create_perms(dsl_dir_t *sdd, dmu_tx_t *tx, cred_t *cr)
717 {
718 	dsl_dir_t *dd;
719 	uint64_t uid = crgetuid(cr);
720 
721 	if (spa_version(dmu_objset_spa(sdd->dd_pool->dp_meta_objset)) <
722 	    SPA_VERSION_DELEGATED_PERMS)
723 		return;
724 
725 	for (dd = sdd->dd_parent; dd != NULL; dd = dd->dd_parent) {
726 		uint64_t pzapobj = dsl_dir_phys(dd)->dd_deleg_zapobj;
727 
728 		if (pzapobj == 0)
729 			continue;
730 
731 		copy_create_perms(sdd, pzapobj, B_FALSE, uid, tx);
732 		copy_create_perms(sdd, pzapobj, B_TRUE, uid, tx);
733 	}
734 }
735 
736 int
dsl_deleg_destroy(objset_t * mos,uint64_t zapobj,dmu_tx_t * tx)737 dsl_deleg_destroy(objset_t *mos, uint64_t zapobj, dmu_tx_t *tx)
738 {
739 	zap_cursor_t zc;
740 	zap_attribute_t za;
741 
742 	if (zapobj == 0)
743 		return (0);
744 
745 	for (zap_cursor_init(&zc, mos, zapobj);
746 	    zap_cursor_retrieve(&zc, &za) == 0;
747 	    zap_cursor_advance(&zc)) {
748 		ASSERT(za.za_integer_length == 8 && za.za_num_integers == 1);
749 		VERIFY(0 == zap_destroy(mos, za.za_first_integer, tx));
750 	}
751 	zap_cursor_fini(&zc);
752 	VERIFY(0 == zap_destroy(mos, zapobj, tx));
753 	return (0);
754 }
755 
756 boolean_t
dsl_delegation_on(objset_t * os)757 dsl_delegation_on(objset_t *os)
758 {
759 	return (!!spa_delegation(os->os_spa));
760 }
761