xref: /freebsd/sys/contrib/openzfs/module/zfs/dsl_crypt.c (revision d9a42747950146bf03cda7f6e25d219253f8a57a)
1 /*
2  * CDDL HEADER START
3  *
4  * This file and its contents are supplied under the terms of the
5  * Common Development and Distribution License ("CDDL"), version 1.0.
6  * You may only use this file in accordance with the terms of version
7  * 1.0 of the CDDL.
8  *
9  * A full copy of the text of the CDDL should have accompanied this
10  * source.  A copy of the CDDL is also available via the Internet at
11  * http://www.illumos.org/license/CDDL.
12  *
13  * CDDL HEADER END
14  */
15 
16 /*
17  * Copyright (c) 2017, Datto, Inc. All rights reserved.
18  * Copyright (c) 2018 by Delphix. All rights reserved.
19  */
20 
21 #include <sys/dsl_crypt.h>
22 #include <sys/dsl_pool.h>
23 #include <sys/zap.h>
24 #include <sys/zil.h>
25 #include <sys/dsl_dir.h>
26 #include <sys/dsl_prop.h>
27 #include <sys/spa_impl.h>
28 #include <sys/dmu_objset.h>
29 #include <sys/zvol.h>
30 
31 /*
32  * This file's primary purpose is for managing master encryption keys in
33  * memory and on disk. For more info on how these keys are used, see the
34  * block comment in zio_crypt.c.
35  *
36  * All master keys are stored encrypted on disk in the form of the DSL
37  * Crypto Key ZAP object. The binary key data in this object is always
38  * randomly generated and is encrypted with the user's wrapping key. This
39  * layer of indirection allows the user to change their key without
40  * needing to re-encrypt the entire dataset. The ZAP also holds on to the
41  * (non-encrypted) encryption algorithm identifier, IV, and MAC needed to
42  * safely decrypt the master key. For more info on the user's key see the
43  * block comment in libzfs_crypto.c
44  *
45  * In-memory encryption keys are managed through the spa_keystore. The
46  * keystore consists of 3 AVL trees, which are as follows:
47  *
48  * The Wrapping Key Tree:
49  * The wrapping key (wkey) tree stores the user's keys that are fed into the
50  * kernel through 'zfs load-key' and related commands. Datasets inherit their
51  * parent's wkey by default, so these structures are refcounted. The wrapping
52  * keys remain in memory until they are explicitly unloaded (with
53  * "zfs unload-key"). Unloading is only possible when no datasets are using
54  * them (refcount=0).
55  *
56  * The DSL Crypto Key Tree:
57  * The DSL Crypto Keys (DCK) are the in-memory representation of decrypted
58  * master keys. They are used by the functions in zio_crypt.c to perform
59  * encryption, decryption, and authentication. Snapshots and clones of a given
60  * dataset will share a DSL Crypto Key, so they are also refcounted. Once the
61  * refcount on a key hits zero, it is immediately zeroed out and freed.
62  *
63  * The Crypto Key Mapping Tree:
64  * The zio layer needs to lookup master keys by their dataset object id. Since
65  * the DSL Crypto Keys can belong to multiple datasets, we maintain a tree of
66  * dsl_key_mapping_t's which essentially just map the dataset object id to its
67  * appropriate DSL Crypto Key. The management for creating and destroying these
68  * mappings hooks into the code for owning and disowning datasets. Usually,
69  * there will only be one active dataset owner, but there are times
70  * (particularly during dataset creation and destruction) when this may not be
71  * true or the dataset may not be initialized enough to own. As a result, this
72  * object is also refcounted.
73  */
74 
75 /*
76  * This tunable allows datasets to be raw received even if the stream does
77  * not include IVset guids or if the guids don't match. This is used as part
78  * of the resolution for ZPOOL_ERRATA_ZOL_8308_ENCRYPTION.
79  */
80 int zfs_disable_ivset_guid_check = 0;
81 
82 static void
83 dsl_wrapping_key_hold(dsl_wrapping_key_t *wkey, const void *tag)
84 {
85 	(void) zfs_refcount_add(&wkey->wk_refcnt, tag);
86 }
87 
88 static void
89 dsl_wrapping_key_rele(dsl_wrapping_key_t *wkey, const void *tag)
90 {
91 	(void) zfs_refcount_remove(&wkey->wk_refcnt, tag);
92 }
93 
94 static void
95 dsl_wrapping_key_free(dsl_wrapping_key_t *wkey)
96 {
97 	ASSERT0(zfs_refcount_count(&wkey->wk_refcnt));
98 
99 	if (wkey->wk_key.ck_data) {
100 		memset(wkey->wk_key.ck_data, 0,
101 		    CRYPTO_BITS2BYTES(wkey->wk_key.ck_length));
102 		kmem_free(wkey->wk_key.ck_data,
103 		    CRYPTO_BITS2BYTES(wkey->wk_key.ck_length));
104 	}
105 
106 	zfs_refcount_destroy(&wkey->wk_refcnt);
107 	kmem_free(wkey, sizeof (dsl_wrapping_key_t));
108 }
109 
110 static void
111 dsl_wrapping_key_create(uint8_t *wkeydata, zfs_keyformat_t keyformat,
112     uint64_t salt, uint64_t iters, dsl_wrapping_key_t **wkey_out)
113 {
114 	dsl_wrapping_key_t *wkey;
115 
116 	/* allocate the wrapping key */
117 	wkey = kmem_alloc(sizeof (dsl_wrapping_key_t), KM_SLEEP);
118 
119 	/* allocate and initialize the underlying crypto key */
120 	wkey->wk_key.ck_data = kmem_alloc(WRAPPING_KEY_LEN, KM_SLEEP);
121 
122 	wkey->wk_key.ck_length = CRYPTO_BYTES2BITS(WRAPPING_KEY_LEN);
123 	memcpy(wkey->wk_key.ck_data, wkeydata, WRAPPING_KEY_LEN);
124 
125 	/* initialize the rest of the struct */
126 	zfs_refcount_create(&wkey->wk_refcnt);
127 	wkey->wk_keyformat = keyformat;
128 	wkey->wk_salt = salt;
129 	wkey->wk_iters = iters;
130 
131 	*wkey_out = wkey;
132 }
133 
134 int
135 dsl_crypto_params_create_nvlist(dcp_cmd_t cmd, nvlist_t *props,
136     nvlist_t *crypto_args, dsl_crypto_params_t **dcp_out)
137 {
138 	int ret;
139 	uint64_t crypt = ZIO_CRYPT_INHERIT;
140 	uint64_t keyformat = ZFS_KEYFORMAT_NONE;
141 	uint64_t salt = 0, iters = 0;
142 	dsl_crypto_params_t *dcp = NULL;
143 	dsl_wrapping_key_t *wkey = NULL;
144 	uint8_t *wkeydata = NULL;
145 	uint_t wkeydata_len = 0;
146 	const char *keylocation = NULL;
147 
148 	dcp = kmem_zalloc(sizeof (dsl_crypto_params_t), KM_SLEEP);
149 	dcp->cp_cmd = cmd;
150 
151 	/* get relevant arguments from the nvlists */
152 	if (props != NULL) {
153 		(void) nvlist_lookup_uint64(props,
154 		    zfs_prop_to_name(ZFS_PROP_ENCRYPTION), &crypt);
155 		(void) nvlist_lookup_uint64(props,
156 		    zfs_prop_to_name(ZFS_PROP_KEYFORMAT), &keyformat);
157 		(void) nvlist_lookup_string(props,
158 		    zfs_prop_to_name(ZFS_PROP_KEYLOCATION), &keylocation);
159 		(void) nvlist_lookup_uint64(props,
160 		    zfs_prop_to_name(ZFS_PROP_PBKDF2_SALT), &salt);
161 		(void) nvlist_lookup_uint64(props,
162 		    zfs_prop_to_name(ZFS_PROP_PBKDF2_ITERS), &iters);
163 
164 		dcp->cp_crypt = crypt;
165 	}
166 
167 	if (crypto_args != NULL) {
168 		(void) nvlist_lookup_uint8_array(crypto_args, "wkeydata",
169 		    &wkeydata, &wkeydata_len);
170 	}
171 
172 	/* check for valid command */
173 	if (dcp->cp_cmd >= DCP_CMD_MAX) {
174 		ret = SET_ERROR(EINVAL);
175 		goto error;
176 	} else {
177 		dcp->cp_cmd = cmd;
178 	}
179 
180 	/* check for valid crypt */
181 	if (dcp->cp_crypt >= ZIO_CRYPT_FUNCTIONS) {
182 		ret = SET_ERROR(EINVAL);
183 		goto error;
184 	} else {
185 		dcp->cp_crypt = crypt;
186 	}
187 
188 	/* check for valid keyformat */
189 	if (keyformat >= ZFS_KEYFORMAT_FORMATS) {
190 		ret = SET_ERROR(EINVAL);
191 		goto error;
192 	}
193 
194 	/* check for a valid keylocation (of any kind) and copy it in */
195 	if (keylocation != NULL) {
196 		if (!zfs_prop_valid_keylocation(keylocation, B_FALSE)) {
197 			ret = SET_ERROR(EINVAL);
198 			goto error;
199 		}
200 
201 		dcp->cp_keylocation = spa_strdup(keylocation);
202 	}
203 
204 	/* check wrapping key length, if given */
205 	if (wkeydata != NULL && wkeydata_len != WRAPPING_KEY_LEN) {
206 		ret = SET_ERROR(EINVAL);
207 		goto error;
208 	}
209 
210 	/* if the user asked for the default crypt, determine that now */
211 	if (dcp->cp_crypt == ZIO_CRYPT_ON)
212 		dcp->cp_crypt = ZIO_CRYPT_ON_VALUE;
213 
214 	/* create the wrapping key from the raw data */
215 	if (wkeydata != NULL) {
216 		/* create the wrapping key with the verified parameters */
217 		dsl_wrapping_key_create(wkeydata, keyformat, salt,
218 		    iters, &wkey);
219 		dcp->cp_wkey = wkey;
220 	}
221 
222 	/*
223 	 * Remove the encryption properties from the nvlist since they are not
224 	 * maintained through the DSL.
225 	 */
226 	(void) nvlist_remove_all(props, zfs_prop_to_name(ZFS_PROP_ENCRYPTION));
227 	(void) nvlist_remove_all(props, zfs_prop_to_name(ZFS_PROP_KEYFORMAT));
228 	(void) nvlist_remove_all(props, zfs_prop_to_name(ZFS_PROP_PBKDF2_SALT));
229 	(void) nvlist_remove_all(props,
230 	    zfs_prop_to_name(ZFS_PROP_PBKDF2_ITERS));
231 
232 	*dcp_out = dcp;
233 
234 	return (0);
235 
236 error:
237 	kmem_free(dcp, sizeof (dsl_crypto_params_t));
238 	*dcp_out = NULL;
239 	return (ret);
240 }
241 
242 void
243 dsl_crypto_params_free(dsl_crypto_params_t *dcp, boolean_t unload)
244 {
245 	if (dcp == NULL)
246 		return;
247 
248 	if (dcp->cp_keylocation != NULL)
249 		spa_strfree(dcp->cp_keylocation);
250 	if (unload && dcp->cp_wkey != NULL)
251 		dsl_wrapping_key_free(dcp->cp_wkey);
252 
253 	kmem_free(dcp, sizeof (dsl_crypto_params_t));
254 }
255 
256 static int
257 spa_crypto_key_compare(const void *a, const void *b)
258 {
259 	const dsl_crypto_key_t *dcka = a;
260 	const dsl_crypto_key_t *dckb = b;
261 
262 	if (dcka->dck_obj < dckb->dck_obj)
263 		return (-1);
264 	if (dcka->dck_obj > dckb->dck_obj)
265 		return (1);
266 	return (0);
267 }
268 
269 static int
270 spa_key_mapping_compare(const void *a, const void *b)
271 {
272 	const dsl_key_mapping_t *kma = a;
273 	const dsl_key_mapping_t *kmb = b;
274 
275 	if (kma->km_dsobj < kmb->km_dsobj)
276 		return (-1);
277 	if (kma->km_dsobj > kmb->km_dsobj)
278 		return (1);
279 	return (0);
280 }
281 
282 static int
283 spa_wkey_compare(const void *a, const void *b)
284 {
285 	const dsl_wrapping_key_t *wka = a;
286 	const dsl_wrapping_key_t *wkb = b;
287 
288 	if (wka->wk_ddobj < wkb->wk_ddobj)
289 		return (-1);
290 	if (wka->wk_ddobj > wkb->wk_ddobj)
291 		return (1);
292 	return (0);
293 }
294 
295 void
296 spa_keystore_init(spa_keystore_t *sk)
297 {
298 	rw_init(&sk->sk_dk_lock, NULL, RW_DEFAULT, NULL);
299 	rw_init(&sk->sk_km_lock, NULL, RW_DEFAULT, NULL);
300 	rw_init(&sk->sk_wkeys_lock, NULL, RW_DEFAULT, NULL);
301 	avl_create(&sk->sk_dsl_keys, spa_crypto_key_compare,
302 	    sizeof (dsl_crypto_key_t),
303 	    offsetof(dsl_crypto_key_t, dck_avl_link));
304 	avl_create(&sk->sk_key_mappings, spa_key_mapping_compare,
305 	    sizeof (dsl_key_mapping_t),
306 	    offsetof(dsl_key_mapping_t, km_avl_link));
307 	avl_create(&sk->sk_wkeys, spa_wkey_compare, sizeof (dsl_wrapping_key_t),
308 	    offsetof(dsl_wrapping_key_t, wk_avl_link));
309 }
310 
311 void
312 spa_keystore_fini(spa_keystore_t *sk)
313 {
314 	dsl_wrapping_key_t *wkey;
315 	void *cookie = NULL;
316 
317 	ASSERT(avl_is_empty(&sk->sk_dsl_keys));
318 	ASSERT(avl_is_empty(&sk->sk_key_mappings));
319 
320 	while ((wkey = avl_destroy_nodes(&sk->sk_wkeys, &cookie)) != NULL)
321 		dsl_wrapping_key_free(wkey);
322 
323 	avl_destroy(&sk->sk_wkeys);
324 	avl_destroy(&sk->sk_key_mappings);
325 	avl_destroy(&sk->sk_dsl_keys);
326 	rw_destroy(&sk->sk_wkeys_lock);
327 	rw_destroy(&sk->sk_km_lock);
328 	rw_destroy(&sk->sk_dk_lock);
329 }
330 
331 static int
332 dsl_dir_get_encryption_root_ddobj(dsl_dir_t *dd, uint64_t *rddobj)
333 {
334 	if (dd->dd_crypto_obj == 0)
335 		return (SET_ERROR(ENOENT));
336 
337 	return (zap_lookup(dd->dd_pool->dp_meta_objset, dd->dd_crypto_obj,
338 	    DSL_CRYPTO_KEY_ROOT_DDOBJ, 8, 1, rddobj));
339 }
340 
341 static int
342 dsl_dir_get_encryption_version(dsl_dir_t *dd, uint64_t *version)
343 {
344 	*version = 0;
345 
346 	if (dd->dd_crypto_obj == 0)
347 		return (SET_ERROR(ENOENT));
348 
349 	/* version 0 is implied by ENOENT */
350 	(void) zap_lookup(dd->dd_pool->dp_meta_objset, dd->dd_crypto_obj,
351 	    DSL_CRYPTO_KEY_VERSION, 8, 1, version);
352 
353 	return (0);
354 }
355 
356 boolean_t
357 dsl_dir_incompatible_encryption_version(dsl_dir_t *dd)
358 {
359 	int ret;
360 	uint64_t version = 0;
361 
362 	ret = dsl_dir_get_encryption_version(dd, &version);
363 	if (ret != 0)
364 		return (B_FALSE);
365 
366 	return (version != ZIO_CRYPT_KEY_CURRENT_VERSION);
367 }
368 
369 static int
370 spa_keystore_wkey_hold_ddobj_impl(spa_t *spa, uint64_t ddobj,
371     const void *tag, dsl_wrapping_key_t **wkey_out)
372 {
373 	int ret;
374 	dsl_wrapping_key_t search_wkey;
375 	dsl_wrapping_key_t *found_wkey;
376 
377 	ASSERT(RW_LOCK_HELD(&spa->spa_keystore.sk_wkeys_lock));
378 
379 	/* init the search wrapping key */
380 	search_wkey.wk_ddobj = ddobj;
381 
382 	/* lookup the wrapping key */
383 	found_wkey = avl_find(&spa->spa_keystore.sk_wkeys, &search_wkey, NULL);
384 	if (!found_wkey) {
385 		ret = SET_ERROR(ENOENT);
386 		goto error;
387 	}
388 
389 	/* increment the refcount */
390 	dsl_wrapping_key_hold(found_wkey, tag);
391 
392 	*wkey_out = found_wkey;
393 	return (0);
394 
395 error:
396 	*wkey_out = NULL;
397 	return (ret);
398 }
399 
400 static int
401 spa_keystore_wkey_hold_dd(spa_t *spa, dsl_dir_t *dd, const void *tag,
402     dsl_wrapping_key_t **wkey_out)
403 {
404 	int ret;
405 	dsl_wrapping_key_t *wkey;
406 	uint64_t rddobj;
407 	boolean_t locked = B_FALSE;
408 
409 	if (!RW_WRITE_HELD(&spa->spa_keystore.sk_wkeys_lock)) {
410 		rw_enter(&spa->spa_keystore.sk_wkeys_lock, RW_READER);
411 		locked = B_TRUE;
412 	}
413 
414 	/* get the ddobj that the keylocation property was inherited from */
415 	ret = dsl_dir_get_encryption_root_ddobj(dd, &rddobj);
416 	if (ret != 0)
417 		goto error;
418 
419 	/* lookup the wkey in the avl tree */
420 	ret = spa_keystore_wkey_hold_ddobj_impl(spa, rddobj, tag, &wkey);
421 	if (ret != 0)
422 		goto error;
423 
424 	/* unlock the wkey tree if we locked it */
425 	if (locked)
426 		rw_exit(&spa->spa_keystore.sk_wkeys_lock);
427 
428 	*wkey_out = wkey;
429 	return (0);
430 
431 error:
432 	if (locked)
433 		rw_exit(&spa->spa_keystore.sk_wkeys_lock);
434 
435 	*wkey_out = NULL;
436 	return (ret);
437 }
438 
439 int
440 dsl_crypto_can_set_keylocation(const char *dsname, const char *keylocation)
441 {
442 	int ret = 0;
443 	dsl_dir_t *dd = NULL;
444 	dsl_pool_t *dp = NULL;
445 	uint64_t rddobj;
446 
447 	/* hold the dsl dir */
448 	ret = dsl_pool_hold(dsname, FTAG, &dp);
449 	if (ret != 0)
450 		goto out;
451 
452 	ret = dsl_dir_hold(dp, dsname, FTAG, &dd, NULL);
453 	if (ret != 0) {
454 		dd = NULL;
455 		goto out;
456 	}
457 
458 	/* if dd is not encrypted, the value may only be "none" */
459 	if (dd->dd_crypto_obj == 0) {
460 		if (strcmp(keylocation, "none") != 0) {
461 			ret = SET_ERROR(EACCES);
462 			goto out;
463 		}
464 
465 		ret = 0;
466 		goto out;
467 	}
468 
469 	/* check for a valid keylocation for encrypted datasets */
470 	if (!zfs_prop_valid_keylocation(keylocation, B_TRUE)) {
471 		ret = SET_ERROR(EINVAL);
472 		goto out;
473 	}
474 
475 	/* check that this is an encryption root */
476 	ret = dsl_dir_get_encryption_root_ddobj(dd, &rddobj);
477 	if (ret != 0)
478 		goto out;
479 
480 	if (rddobj != dd->dd_object) {
481 		ret = SET_ERROR(EACCES);
482 		goto out;
483 	}
484 
485 	dsl_dir_rele(dd, FTAG);
486 	dsl_pool_rele(dp, FTAG);
487 
488 	return (0);
489 
490 out:
491 	if (dd != NULL)
492 		dsl_dir_rele(dd, FTAG);
493 	if (dp != NULL)
494 		dsl_pool_rele(dp, FTAG);
495 
496 	return (ret);
497 }
498 
499 static void
500 dsl_crypto_key_free(dsl_crypto_key_t *dck)
501 {
502 	ASSERT(zfs_refcount_count(&dck->dck_holds) == 0);
503 
504 	/* destroy the zio_crypt_key_t */
505 	zio_crypt_key_destroy(&dck->dck_key);
506 
507 	/* free the refcount, wrapping key, and lock */
508 	zfs_refcount_destroy(&dck->dck_holds);
509 	if (dck->dck_wkey)
510 		dsl_wrapping_key_rele(dck->dck_wkey, dck);
511 
512 	/* free the key */
513 	kmem_free(dck, sizeof (dsl_crypto_key_t));
514 }
515 
516 static void
517 dsl_crypto_key_rele(dsl_crypto_key_t *dck, const void *tag)
518 {
519 	if (zfs_refcount_remove(&dck->dck_holds, tag) == 0)
520 		dsl_crypto_key_free(dck);
521 }
522 
523 static int
524 dsl_crypto_key_open(objset_t *mos, dsl_wrapping_key_t *wkey,
525     uint64_t dckobj, const void *tag, dsl_crypto_key_t **dck_out)
526 {
527 	int ret;
528 	uint64_t crypt = 0, guid = 0, version = 0;
529 	uint8_t raw_keydata[MASTER_KEY_MAX_LEN];
530 	uint8_t raw_hmac_keydata[SHA512_HMAC_KEYLEN];
531 	uint8_t iv[WRAPPING_IV_LEN];
532 	uint8_t mac[WRAPPING_MAC_LEN];
533 	dsl_crypto_key_t *dck;
534 
535 	/* allocate and initialize the key */
536 	dck = kmem_zalloc(sizeof (dsl_crypto_key_t), KM_SLEEP);
537 
538 	/* fetch all of the values we need from the ZAP */
539 	ret = zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_CRYPTO_SUITE, 8, 1,
540 	    &crypt);
541 	if (ret != 0)
542 		goto error;
543 
544 	/* handle a future crypto suite that we don't support */
545 	if (crypt >= ZIO_CRYPT_FUNCTIONS) {
546 		ret = (SET_ERROR(ZFS_ERR_CRYPTO_NOTSUP));
547 		goto error;
548 	}
549 
550 	ret = zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_GUID, 8, 1, &guid);
551 	if (ret != 0)
552 		goto error;
553 
554 	ret = zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_MASTER_KEY, 1,
555 	    MASTER_KEY_MAX_LEN, raw_keydata);
556 	if (ret != 0)
557 		goto error;
558 
559 	ret = zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_HMAC_KEY, 1,
560 	    SHA512_HMAC_KEYLEN, raw_hmac_keydata);
561 	if (ret != 0)
562 		goto error;
563 
564 	ret = zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_IV, 1, WRAPPING_IV_LEN,
565 	    iv);
566 	if (ret != 0)
567 		goto error;
568 
569 	ret = zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_MAC, 1, WRAPPING_MAC_LEN,
570 	    mac);
571 	if (ret != 0)
572 		goto error;
573 
574 	/* the initial on-disk format for encryption did not have a version */
575 	(void) zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_VERSION, 8, 1, &version);
576 
577 	/*
578 	 * Unwrap the keys. If there is an error return EACCES to indicate
579 	 * an authentication failure.
580 	 */
581 	ret = zio_crypt_key_unwrap(&wkey->wk_key, crypt, version, guid,
582 	    raw_keydata, raw_hmac_keydata, iv, mac, &dck->dck_key);
583 	if (ret != 0) {
584 		ret = SET_ERROR(EACCES);
585 		goto error;
586 	}
587 
588 	/* finish initializing the dsl_crypto_key_t */
589 	zfs_refcount_create(&dck->dck_holds);
590 	dsl_wrapping_key_hold(wkey, dck);
591 	dck->dck_wkey = wkey;
592 	dck->dck_obj = dckobj;
593 	zfs_refcount_add(&dck->dck_holds, tag);
594 
595 	*dck_out = dck;
596 	return (0);
597 
598 error:
599 	if (dck != NULL) {
600 		memset(dck, 0, sizeof (dsl_crypto_key_t));
601 		kmem_free(dck, sizeof (dsl_crypto_key_t));
602 	}
603 
604 	*dck_out = NULL;
605 	return (ret);
606 }
607 
608 static int
609 spa_keystore_dsl_key_hold_impl(spa_t *spa, uint64_t dckobj, const void *tag,
610     dsl_crypto_key_t **dck_out)
611 {
612 	int ret;
613 	dsl_crypto_key_t search_dck;
614 	dsl_crypto_key_t *found_dck;
615 
616 	ASSERT(RW_LOCK_HELD(&spa->spa_keystore.sk_dk_lock));
617 
618 	/* init the search key */
619 	search_dck.dck_obj = dckobj;
620 
621 	/* find the matching key in the keystore */
622 	found_dck = avl_find(&spa->spa_keystore.sk_dsl_keys, &search_dck, NULL);
623 	if (!found_dck) {
624 		ret = SET_ERROR(ENOENT);
625 		goto error;
626 	}
627 
628 	/* increment the refcount */
629 	zfs_refcount_add(&found_dck->dck_holds, tag);
630 
631 	*dck_out = found_dck;
632 	return (0);
633 
634 error:
635 	*dck_out = NULL;
636 	return (ret);
637 }
638 
639 static int
640 spa_keystore_dsl_key_hold_dd(spa_t *spa, dsl_dir_t *dd, const void *tag,
641     dsl_crypto_key_t **dck_out)
642 {
643 	int ret;
644 	avl_index_t where;
645 	dsl_crypto_key_t *dck_io = NULL, *dck_ks = NULL;
646 	dsl_wrapping_key_t *wkey = NULL;
647 	uint64_t dckobj = dd->dd_crypto_obj;
648 
649 	/* Lookup the key in the tree of currently loaded keys */
650 	rw_enter(&spa->spa_keystore.sk_dk_lock, RW_READER);
651 	ret = spa_keystore_dsl_key_hold_impl(spa, dckobj, tag, &dck_ks);
652 	rw_exit(&spa->spa_keystore.sk_dk_lock);
653 	if (ret == 0) {
654 		*dck_out = dck_ks;
655 		return (0);
656 	}
657 
658 	/* Lookup the wrapping key from the keystore */
659 	ret = spa_keystore_wkey_hold_dd(spa, dd, FTAG, &wkey);
660 	if (ret != 0) {
661 		*dck_out = NULL;
662 		return (SET_ERROR(EACCES));
663 	}
664 
665 	/* Read the key from disk */
666 	ret = dsl_crypto_key_open(spa->spa_meta_objset, wkey, dckobj,
667 	    tag, &dck_io);
668 	if (ret != 0) {
669 		dsl_wrapping_key_rele(wkey, FTAG);
670 		*dck_out = NULL;
671 		return (ret);
672 	}
673 
674 	/*
675 	 * Add the key to the keystore.  It may already exist if it was
676 	 * added while performing the read from disk.  In this case discard
677 	 * it and return the key from the keystore.
678 	 */
679 	rw_enter(&spa->spa_keystore.sk_dk_lock, RW_WRITER);
680 	ret = spa_keystore_dsl_key_hold_impl(spa, dckobj, tag, &dck_ks);
681 	if (ret != 0) {
682 		avl_find(&spa->spa_keystore.sk_dsl_keys, dck_io, &where);
683 		avl_insert(&spa->spa_keystore.sk_dsl_keys, dck_io, where);
684 		*dck_out = dck_io;
685 	} else {
686 		dsl_crypto_key_free(dck_io);
687 		*dck_out = dck_ks;
688 	}
689 
690 	/* Release the wrapping key (the dsl key now has a reference to it) */
691 	dsl_wrapping_key_rele(wkey, FTAG);
692 	rw_exit(&spa->spa_keystore.sk_dk_lock);
693 
694 	return (0);
695 }
696 
697 void
698 spa_keystore_dsl_key_rele(spa_t *spa, dsl_crypto_key_t *dck, const void *tag)
699 {
700 	rw_enter(&spa->spa_keystore.sk_dk_lock, RW_WRITER);
701 
702 	if (zfs_refcount_remove(&dck->dck_holds, tag) == 0) {
703 		avl_remove(&spa->spa_keystore.sk_dsl_keys, dck);
704 		dsl_crypto_key_free(dck);
705 	}
706 
707 	rw_exit(&spa->spa_keystore.sk_dk_lock);
708 }
709 
710 int
711 spa_keystore_load_wkey_impl(spa_t *spa, dsl_wrapping_key_t *wkey)
712 {
713 	int ret;
714 	avl_index_t where;
715 	dsl_wrapping_key_t *found_wkey;
716 
717 	rw_enter(&spa->spa_keystore.sk_wkeys_lock, RW_WRITER);
718 
719 	/* insert the wrapping key into the keystore */
720 	found_wkey = avl_find(&spa->spa_keystore.sk_wkeys, wkey, &where);
721 	if (found_wkey != NULL) {
722 		ret = SET_ERROR(EEXIST);
723 		goto error_unlock;
724 	}
725 	avl_insert(&spa->spa_keystore.sk_wkeys, wkey, where);
726 
727 	rw_exit(&spa->spa_keystore.sk_wkeys_lock);
728 
729 	return (0);
730 
731 error_unlock:
732 	rw_exit(&spa->spa_keystore.sk_wkeys_lock);
733 	return (ret);
734 }
735 
736 int
737 spa_keystore_load_wkey(const char *dsname, dsl_crypto_params_t *dcp,
738     boolean_t noop)
739 {
740 	int ret;
741 	dsl_dir_t *dd = NULL;
742 	dsl_crypto_key_t *dck = NULL;
743 	dsl_wrapping_key_t *wkey = dcp->cp_wkey;
744 	dsl_pool_t *dp = NULL;
745 	uint64_t rddobj, keyformat, salt, iters;
746 
747 	/*
748 	 * We don't validate the wrapping key's keyformat, salt, or iters
749 	 * since they will never be needed after the DCK has been wrapped.
750 	 */
751 	if (dcp->cp_wkey == NULL ||
752 	    dcp->cp_cmd != DCP_CMD_NONE ||
753 	    dcp->cp_crypt != ZIO_CRYPT_INHERIT ||
754 	    dcp->cp_keylocation != NULL)
755 		return (SET_ERROR(EINVAL));
756 
757 	ret = dsl_pool_hold(dsname, FTAG, &dp);
758 	if (ret != 0)
759 		goto error;
760 
761 	if (!spa_feature_is_enabled(dp->dp_spa, SPA_FEATURE_ENCRYPTION)) {
762 		ret = SET_ERROR(ENOTSUP);
763 		goto error;
764 	}
765 
766 	/* hold the dsl dir */
767 	ret = dsl_dir_hold(dp, dsname, FTAG, &dd, NULL);
768 	if (ret != 0) {
769 		dd = NULL;
770 		goto error;
771 	}
772 
773 	/* confirm that dd is the encryption root */
774 	ret = dsl_dir_get_encryption_root_ddobj(dd, &rddobj);
775 	if (ret != 0 || rddobj != dd->dd_object) {
776 		ret = SET_ERROR(EINVAL);
777 		goto error;
778 	}
779 
780 	/* initialize the wkey's ddobj */
781 	wkey->wk_ddobj = dd->dd_object;
782 
783 	/* verify that the wkey is correct by opening its dsl key */
784 	ret = dsl_crypto_key_open(dp->dp_meta_objset, wkey,
785 	    dd->dd_crypto_obj, FTAG, &dck);
786 	if (ret != 0)
787 		goto error;
788 
789 	/* initialize the wkey encryption parameters from the DSL Crypto Key */
790 	ret = zap_lookup(dp->dp_meta_objset, dd->dd_crypto_obj,
791 	    zfs_prop_to_name(ZFS_PROP_KEYFORMAT), 8, 1, &keyformat);
792 	if (ret != 0)
793 		goto error;
794 
795 	ret = zap_lookup(dp->dp_meta_objset, dd->dd_crypto_obj,
796 	    zfs_prop_to_name(ZFS_PROP_PBKDF2_SALT), 8, 1, &salt);
797 	if (ret != 0)
798 		goto error;
799 
800 	ret = zap_lookup(dp->dp_meta_objset, dd->dd_crypto_obj,
801 	    zfs_prop_to_name(ZFS_PROP_PBKDF2_ITERS), 8, 1, &iters);
802 	if (ret != 0)
803 		goto error;
804 
805 	ASSERT3U(keyformat, <, ZFS_KEYFORMAT_FORMATS);
806 	ASSERT3U(keyformat, !=, ZFS_KEYFORMAT_NONE);
807 	IMPLY(keyformat == ZFS_KEYFORMAT_PASSPHRASE, iters != 0);
808 	IMPLY(keyformat == ZFS_KEYFORMAT_PASSPHRASE, salt != 0);
809 	IMPLY(keyformat != ZFS_KEYFORMAT_PASSPHRASE, iters == 0);
810 	IMPLY(keyformat != ZFS_KEYFORMAT_PASSPHRASE, salt == 0);
811 
812 	wkey->wk_keyformat = keyformat;
813 	wkey->wk_salt = salt;
814 	wkey->wk_iters = iters;
815 
816 	/*
817 	 * At this point we have verified the wkey and confirmed that it can
818 	 * be used to decrypt a DSL Crypto Key. We can simply cleanup and
819 	 * return if this is all the user wanted to do.
820 	 */
821 	if (noop)
822 		goto error;
823 
824 	/* insert the wrapping key into the keystore */
825 	ret = spa_keystore_load_wkey_impl(dp->dp_spa, wkey);
826 	if (ret != 0)
827 		goto error;
828 
829 	dsl_crypto_key_rele(dck, FTAG);
830 	dsl_dir_rele(dd, FTAG);
831 	dsl_pool_rele(dp, FTAG);
832 
833 	/* create any zvols under this ds */
834 	zvol_create_minors_recursive(dsname);
835 
836 	return (0);
837 
838 error:
839 	if (dck != NULL)
840 		dsl_crypto_key_rele(dck, FTAG);
841 	if (dd != NULL)
842 		dsl_dir_rele(dd, FTAG);
843 	if (dp != NULL)
844 		dsl_pool_rele(dp, FTAG);
845 
846 	return (ret);
847 }
848 
849 int
850 spa_keystore_unload_wkey_impl(spa_t *spa, uint64_t ddobj)
851 {
852 	int ret;
853 	dsl_wrapping_key_t search_wkey;
854 	dsl_wrapping_key_t *found_wkey;
855 
856 	/* init the search wrapping key */
857 	search_wkey.wk_ddobj = ddobj;
858 
859 	rw_enter(&spa->spa_keystore.sk_wkeys_lock, RW_WRITER);
860 
861 	/* remove the wrapping key from the keystore */
862 	found_wkey = avl_find(&spa->spa_keystore.sk_wkeys,
863 	    &search_wkey, NULL);
864 	if (!found_wkey) {
865 		ret = SET_ERROR(EACCES);
866 		goto error_unlock;
867 	} else if (zfs_refcount_count(&found_wkey->wk_refcnt) != 0) {
868 		ret = SET_ERROR(EBUSY);
869 		goto error_unlock;
870 	}
871 	avl_remove(&spa->spa_keystore.sk_wkeys, found_wkey);
872 
873 	rw_exit(&spa->spa_keystore.sk_wkeys_lock);
874 
875 	/* free the wrapping key */
876 	dsl_wrapping_key_free(found_wkey);
877 
878 	return (0);
879 
880 error_unlock:
881 	rw_exit(&spa->spa_keystore.sk_wkeys_lock);
882 	return (ret);
883 }
884 
885 int
886 spa_keystore_unload_wkey(const char *dsname)
887 {
888 	int ret = 0;
889 	dsl_dir_t *dd = NULL;
890 	dsl_pool_t *dp = NULL;
891 	spa_t *spa = NULL;
892 
893 	ret = spa_open(dsname, &spa, FTAG);
894 	if (ret != 0)
895 		return (ret);
896 
897 	/*
898 	 * Wait for any outstanding txg IO to complete, releasing any
899 	 * remaining references on the wkey.
900 	 */
901 	if (spa_mode(spa) != SPA_MODE_READ)
902 		txg_wait_synced(spa->spa_dsl_pool, 0);
903 
904 	spa_close(spa, FTAG);
905 
906 	/* hold the dsl dir */
907 	ret = dsl_pool_hold(dsname, FTAG, &dp);
908 	if (ret != 0)
909 		goto error;
910 
911 	if (!spa_feature_is_enabled(dp->dp_spa, SPA_FEATURE_ENCRYPTION)) {
912 		ret = (SET_ERROR(ENOTSUP));
913 		goto error;
914 	}
915 
916 	ret = dsl_dir_hold(dp, dsname, FTAG, &dd, NULL);
917 	if (ret != 0) {
918 		dd = NULL;
919 		goto error;
920 	}
921 
922 	/* unload the wkey */
923 	ret = spa_keystore_unload_wkey_impl(dp->dp_spa, dd->dd_object);
924 	if (ret != 0)
925 		goto error;
926 
927 	dsl_dir_rele(dd, FTAG);
928 	dsl_pool_rele(dp, FTAG);
929 
930 	/* remove any zvols under this ds */
931 	zvol_remove_minors(dp->dp_spa, dsname, B_TRUE);
932 
933 	return (0);
934 
935 error:
936 	if (dd != NULL)
937 		dsl_dir_rele(dd, FTAG);
938 	if (dp != NULL)
939 		dsl_pool_rele(dp, FTAG);
940 
941 	return (ret);
942 }
943 
944 void
945 key_mapping_add_ref(dsl_key_mapping_t *km, const void *tag)
946 {
947 	ASSERT3U(zfs_refcount_count(&km->km_refcnt), >=, 1);
948 	zfs_refcount_add(&km->km_refcnt, tag);
949 }
950 
951 /*
952  * The locking here is a little tricky to ensure we don't cause unnecessary
953  * performance problems. We want to release a key mapping whenever someone
954  * decrements the refcount to 0, but freeing the mapping requires removing
955  * it from the spa_keystore, which requires holding sk_km_lock as a writer.
956  * Most of the time we don't want to hold this lock as a writer, since the
957  * same lock is held as a reader for each IO that needs to encrypt / decrypt
958  * data for any dataset and in practice we will only actually free the
959  * mapping after unmounting a dataset.
960  */
961 void
962 key_mapping_rele(spa_t *spa, dsl_key_mapping_t *km, const void *tag)
963 {
964 	ASSERT3U(zfs_refcount_count(&km->km_refcnt), >=, 1);
965 
966 	if (zfs_refcount_remove(&km->km_refcnt, tag) != 0)
967 		return;
968 
969 	/*
970 	 * We think we are going to need to free the mapping. Add a
971 	 * reference to prevent most other releasers from thinking
972 	 * this might be their responsibility. This is inherently
973 	 * racy, so we will confirm that we are legitimately the
974 	 * last holder once we have the sk_km_lock as a writer.
975 	 */
976 	zfs_refcount_add(&km->km_refcnt, FTAG);
977 
978 	rw_enter(&spa->spa_keystore.sk_km_lock, RW_WRITER);
979 	if (zfs_refcount_remove(&km->km_refcnt, FTAG) != 0) {
980 		rw_exit(&spa->spa_keystore.sk_km_lock);
981 		return;
982 	}
983 
984 	avl_remove(&spa->spa_keystore.sk_key_mappings, km);
985 	rw_exit(&spa->spa_keystore.sk_km_lock);
986 
987 	spa_keystore_dsl_key_rele(spa, km->km_key, km);
988 	zfs_refcount_destroy(&km->km_refcnt);
989 	kmem_free(km, sizeof (dsl_key_mapping_t));
990 }
991 
992 int
993 spa_keystore_create_mapping(spa_t *spa, dsl_dataset_t *ds, const void *tag,
994     dsl_key_mapping_t **km_out)
995 {
996 	int ret;
997 	avl_index_t where;
998 	dsl_key_mapping_t *km, *found_km;
999 	boolean_t should_free = B_FALSE;
1000 
1001 	/* Allocate and initialize the mapping */
1002 	km = kmem_zalloc(sizeof (dsl_key_mapping_t), KM_SLEEP);
1003 	zfs_refcount_create(&km->km_refcnt);
1004 
1005 	ret = spa_keystore_dsl_key_hold_dd(spa, ds->ds_dir, km, &km->km_key);
1006 	if (ret != 0) {
1007 		zfs_refcount_destroy(&km->km_refcnt);
1008 		kmem_free(km, sizeof (dsl_key_mapping_t));
1009 
1010 		if (km_out != NULL)
1011 			*km_out = NULL;
1012 		return (ret);
1013 	}
1014 
1015 	km->km_dsobj = ds->ds_object;
1016 
1017 	rw_enter(&spa->spa_keystore.sk_km_lock, RW_WRITER);
1018 
1019 	/*
1020 	 * If a mapping already exists, simply increment its refcount and
1021 	 * cleanup the one we made. We want to allocate / free outside of
1022 	 * the lock because this lock is also used by the zio layer to lookup
1023 	 * key mappings. Otherwise, use the one we created. Normally, there will
1024 	 * only be one active reference at a time (the objset owner), but there
1025 	 * are times when there could be multiple async users.
1026 	 */
1027 	found_km = avl_find(&spa->spa_keystore.sk_key_mappings, km, &where);
1028 	if (found_km != NULL) {
1029 		should_free = B_TRUE;
1030 		zfs_refcount_add(&found_km->km_refcnt, tag);
1031 		if (km_out != NULL)
1032 			*km_out = found_km;
1033 	} else {
1034 		zfs_refcount_add(&km->km_refcnt, tag);
1035 		avl_insert(&spa->spa_keystore.sk_key_mappings, km, where);
1036 		if (km_out != NULL)
1037 			*km_out = km;
1038 	}
1039 
1040 	rw_exit(&spa->spa_keystore.sk_km_lock);
1041 
1042 	if (should_free) {
1043 		spa_keystore_dsl_key_rele(spa, km->km_key, km);
1044 		zfs_refcount_destroy(&km->km_refcnt);
1045 		kmem_free(km, sizeof (dsl_key_mapping_t));
1046 	}
1047 
1048 	return (0);
1049 }
1050 
1051 int
1052 spa_keystore_remove_mapping(spa_t *spa, uint64_t dsobj, const void *tag)
1053 {
1054 	int ret;
1055 	dsl_key_mapping_t search_km;
1056 	dsl_key_mapping_t *found_km;
1057 
1058 	/* init the search key mapping */
1059 	search_km.km_dsobj = dsobj;
1060 
1061 	rw_enter(&spa->spa_keystore.sk_km_lock, RW_READER);
1062 
1063 	/* find the matching mapping */
1064 	found_km = avl_find(&spa->spa_keystore.sk_key_mappings,
1065 	    &search_km, NULL);
1066 	if (found_km == NULL) {
1067 		ret = SET_ERROR(ENOENT);
1068 		goto error_unlock;
1069 	}
1070 
1071 	rw_exit(&spa->spa_keystore.sk_km_lock);
1072 
1073 	key_mapping_rele(spa, found_km, tag);
1074 
1075 	return (0);
1076 
1077 error_unlock:
1078 	rw_exit(&spa->spa_keystore.sk_km_lock);
1079 	return (ret);
1080 }
1081 
1082 /*
1083  * This function is primarily used by the zio and arc layer to lookup
1084  * DSL Crypto Keys for encryption. Callers must release the key with
1085  * spa_keystore_dsl_key_rele(). The function may also be called with
1086  * dck_out == NULL and tag == NULL to simply check that a key exists
1087  * without getting a reference to it.
1088  */
1089 int
1090 spa_keystore_lookup_key(spa_t *spa, uint64_t dsobj, const void *tag,
1091     dsl_crypto_key_t **dck_out)
1092 {
1093 	int ret;
1094 	dsl_key_mapping_t search_km;
1095 	dsl_key_mapping_t *found_km;
1096 
1097 	ASSERT((tag != NULL && dck_out != NULL) ||
1098 	    (tag == NULL && dck_out == NULL));
1099 
1100 	/* init the search key mapping */
1101 	search_km.km_dsobj = dsobj;
1102 
1103 	rw_enter(&spa->spa_keystore.sk_km_lock, RW_READER);
1104 
1105 	/* remove the mapping from the tree */
1106 	found_km = avl_find(&spa->spa_keystore.sk_key_mappings, &search_km,
1107 	    NULL);
1108 	if (found_km == NULL) {
1109 		ret = SET_ERROR(ENOENT);
1110 		goto error_unlock;
1111 	}
1112 
1113 	if (found_km && tag)
1114 		zfs_refcount_add(&found_km->km_key->dck_holds, tag);
1115 
1116 	rw_exit(&spa->spa_keystore.sk_km_lock);
1117 
1118 	if (dck_out != NULL)
1119 		*dck_out = found_km->km_key;
1120 	return (0);
1121 
1122 error_unlock:
1123 	rw_exit(&spa->spa_keystore.sk_km_lock);
1124 
1125 	if (dck_out != NULL)
1126 		*dck_out = NULL;
1127 	return (ret);
1128 }
1129 
1130 static int
1131 dmu_objset_check_wkey_loaded(dsl_dir_t *dd)
1132 {
1133 	int ret;
1134 	dsl_wrapping_key_t *wkey = NULL;
1135 
1136 	ret = spa_keystore_wkey_hold_dd(dd->dd_pool->dp_spa, dd, FTAG,
1137 	    &wkey);
1138 	if (ret != 0)
1139 		return (SET_ERROR(EACCES));
1140 
1141 	dsl_wrapping_key_rele(wkey, FTAG);
1142 
1143 	return (0);
1144 }
1145 
1146 zfs_keystatus_t
1147 dsl_dataset_get_keystatus(dsl_dir_t *dd)
1148 {
1149 	/* check if this dd has a has a dsl key */
1150 	if (dd->dd_crypto_obj == 0)
1151 		return (ZFS_KEYSTATUS_NONE);
1152 
1153 	return (dmu_objset_check_wkey_loaded(dd) == 0 ?
1154 	    ZFS_KEYSTATUS_AVAILABLE : ZFS_KEYSTATUS_UNAVAILABLE);
1155 }
1156 
1157 static int
1158 dsl_dir_get_crypt(dsl_dir_t *dd, uint64_t *crypt)
1159 {
1160 	if (dd->dd_crypto_obj == 0) {
1161 		*crypt = ZIO_CRYPT_OFF;
1162 		return (0);
1163 	}
1164 
1165 	return (zap_lookup(dd->dd_pool->dp_meta_objset, dd->dd_crypto_obj,
1166 	    DSL_CRYPTO_KEY_CRYPTO_SUITE, 8, 1, crypt));
1167 }
1168 
1169 static void
1170 dsl_crypto_key_sync_impl(objset_t *mos, uint64_t dckobj, uint64_t crypt,
1171     uint64_t root_ddobj, uint64_t guid, uint8_t *iv, uint8_t *mac,
1172     uint8_t *keydata, uint8_t *hmac_keydata, uint64_t keyformat,
1173     uint64_t salt, uint64_t iters, dmu_tx_t *tx)
1174 {
1175 	VERIFY0(zap_update(mos, dckobj, DSL_CRYPTO_KEY_CRYPTO_SUITE, 8, 1,
1176 	    &crypt, tx));
1177 	VERIFY0(zap_update(mos, dckobj, DSL_CRYPTO_KEY_ROOT_DDOBJ, 8, 1,
1178 	    &root_ddobj, tx));
1179 	VERIFY0(zap_update(mos, dckobj, DSL_CRYPTO_KEY_GUID, 8, 1,
1180 	    &guid, tx));
1181 	VERIFY0(zap_update(mos, dckobj, DSL_CRYPTO_KEY_IV, 1, WRAPPING_IV_LEN,
1182 	    iv, tx));
1183 	VERIFY0(zap_update(mos, dckobj, DSL_CRYPTO_KEY_MAC, 1, WRAPPING_MAC_LEN,
1184 	    mac, tx));
1185 	VERIFY0(zap_update(mos, dckobj, DSL_CRYPTO_KEY_MASTER_KEY, 1,
1186 	    MASTER_KEY_MAX_LEN, keydata, tx));
1187 	VERIFY0(zap_update(mos, dckobj, DSL_CRYPTO_KEY_HMAC_KEY, 1,
1188 	    SHA512_HMAC_KEYLEN, hmac_keydata, tx));
1189 	VERIFY0(zap_update(mos, dckobj, zfs_prop_to_name(ZFS_PROP_KEYFORMAT),
1190 	    8, 1, &keyformat, tx));
1191 	VERIFY0(zap_update(mos, dckobj, zfs_prop_to_name(ZFS_PROP_PBKDF2_SALT),
1192 	    8, 1, &salt, tx));
1193 	VERIFY0(zap_update(mos, dckobj, zfs_prop_to_name(ZFS_PROP_PBKDF2_ITERS),
1194 	    8, 1, &iters, tx));
1195 }
1196 
1197 static void
1198 dsl_crypto_key_sync(dsl_crypto_key_t *dck, dmu_tx_t *tx)
1199 {
1200 	zio_crypt_key_t *key = &dck->dck_key;
1201 	dsl_wrapping_key_t *wkey = dck->dck_wkey;
1202 	uint8_t keydata[MASTER_KEY_MAX_LEN];
1203 	uint8_t hmac_keydata[SHA512_HMAC_KEYLEN];
1204 	uint8_t iv[WRAPPING_IV_LEN];
1205 	uint8_t mac[WRAPPING_MAC_LEN];
1206 
1207 	ASSERT(dmu_tx_is_syncing(tx));
1208 	ASSERT3U(key->zk_crypt, <, ZIO_CRYPT_FUNCTIONS);
1209 
1210 	/* encrypt and store the keys along with the IV and MAC */
1211 	VERIFY0(zio_crypt_key_wrap(&dck->dck_wkey->wk_key, key, iv, mac,
1212 	    keydata, hmac_keydata));
1213 
1214 	/* update the ZAP with the obtained values */
1215 	dsl_crypto_key_sync_impl(tx->tx_pool->dp_meta_objset, dck->dck_obj,
1216 	    key->zk_crypt, wkey->wk_ddobj, key->zk_guid, iv, mac, keydata,
1217 	    hmac_keydata, wkey->wk_keyformat, wkey->wk_salt, wkey->wk_iters,
1218 	    tx);
1219 }
1220 
1221 typedef struct spa_keystore_change_key_args {
1222 	const char *skcka_dsname;
1223 	dsl_crypto_params_t *skcka_cp;
1224 } spa_keystore_change_key_args_t;
1225 
1226 static int
1227 spa_keystore_change_key_check(void *arg, dmu_tx_t *tx)
1228 {
1229 	int ret;
1230 	dsl_dir_t *dd = NULL;
1231 	dsl_pool_t *dp = dmu_tx_pool(tx);
1232 	spa_keystore_change_key_args_t *skcka = arg;
1233 	dsl_crypto_params_t *dcp = skcka->skcka_cp;
1234 	uint64_t rddobj;
1235 
1236 	/* check for the encryption feature */
1237 	if (!spa_feature_is_enabled(dp->dp_spa, SPA_FEATURE_ENCRYPTION)) {
1238 		ret = SET_ERROR(ENOTSUP);
1239 		goto error;
1240 	}
1241 
1242 	/* check for valid key change command */
1243 	if (dcp->cp_cmd != DCP_CMD_NEW_KEY &&
1244 	    dcp->cp_cmd != DCP_CMD_INHERIT &&
1245 	    dcp->cp_cmd != DCP_CMD_FORCE_NEW_KEY &&
1246 	    dcp->cp_cmd != DCP_CMD_FORCE_INHERIT) {
1247 		ret = SET_ERROR(EINVAL);
1248 		goto error;
1249 	}
1250 
1251 	/* hold the dd */
1252 	ret = dsl_dir_hold(dp, skcka->skcka_dsname, FTAG, &dd, NULL);
1253 	if (ret != 0) {
1254 		dd = NULL;
1255 		goto error;
1256 	}
1257 
1258 	/* verify that the dataset is encrypted */
1259 	if (dd->dd_crypto_obj == 0) {
1260 		ret = SET_ERROR(EINVAL);
1261 		goto error;
1262 	}
1263 
1264 	/* clones must always use their origin's key */
1265 	if (dsl_dir_is_clone(dd)) {
1266 		ret = SET_ERROR(EINVAL);
1267 		goto error;
1268 	}
1269 
1270 	/* lookup the ddobj we are inheriting the keylocation from */
1271 	ret = dsl_dir_get_encryption_root_ddobj(dd, &rddobj);
1272 	if (ret != 0)
1273 		goto error;
1274 
1275 	/* Handle inheritance */
1276 	if (dcp->cp_cmd == DCP_CMD_INHERIT ||
1277 	    dcp->cp_cmd == DCP_CMD_FORCE_INHERIT) {
1278 		/* no other encryption params should be given */
1279 		if (dcp->cp_crypt != ZIO_CRYPT_INHERIT ||
1280 		    dcp->cp_keylocation != NULL ||
1281 		    dcp->cp_wkey != NULL) {
1282 			ret = SET_ERROR(EINVAL);
1283 			goto error;
1284 		}
1285 
1286 		/* check that this is an encryption root */
1287 		if (dd->dd_object != rddobj) {
1288 			ret = SET_ERROR(EINVAL);
1289 			goto error;
1290 		}
1291 
1292 		/* check that the parent is encrypted */
1293 		if (dd->dd_parent->dd_crypto_obj == 0) {
1294 			ret = SET_ERROR(EINVAL);
1295 			goto error;
1296 		}
1297 
1298 		/* if we are rewrapping check that both keys are loaded */
1299 		if (dcp->cp_cmd == DCP_CMD_INHERIT) {
1300 			ret = dmu_objset_check_wkey_loaded(dd);
1301 			if (ret != 0)
1302 				goto error;
1303 
1304 			ret = dmu_objset_check_wkey_loaded(dd->dd_parent);
1305 			if (ret != 0)
1306 				goto error;
1307 		}
1308 
1309 		dsl_dir_rele(dd, FTAG);
1310 		return (0);
1311 	}
1312 
1313 	/* handle forcing an encryption root without rewrapping */
1314 	if (dcp->cp_cmd == DCP_CMD_FORCE_NEW_KEY) {
1315 		/* no other encryption params should be given */
1316 		if (dcp->cp_crypt != ZIO_CRYPT_INHERIT ||
1317 		    dcp->cp_keylocation != NULL ||
1318 		    dcp->cp_wkey != NULL) {
1319 			ret = SET_ERROR(EINVAL);
1320 			goto error;
1321 		}
1322 
1323 		/* check that this is not an encryption root */
1324 		if (dd->dd_object == rddobj) {
1325 			ret = SET_ERROR(EINVAL);
1326 			goto error;
1327 		}
1328 
1329 		dsl_dir_rele(dd, FTAG);
1330 		return (0);
1331 	}
1332 
1333 	/* crypt cannot be changed after creation */
1334 	if (dcp->cp_crypt != ZIO_CRYPT_INHERIT) {
1335 		ret = SET_ERROR(EINVAL);
1336 		goto error;
1337 	}
1338 
1339 	/* we are not inheritting our parent's wkey so we need one ourselves */
1340 	if (dcp->cp_wkey == NULL) {
1341 		ret = SET_ERROR(EINVAL);
1342 		goto error;
1343 	}
1344 
1345 	/* check for a valid keyformat for the new wrapping key */
1346 	if (dcp->cp_wkey->wk_keyformat >= ZFS_KEYFORMAT_FORMATS ||
1347 	    dcp->cp_wkey->wk_keyformat == ZFS_KEYFORMAT_NONE) {
1348 		ret = SET_ERROR(EINVAL);
1349 		goto error;
1350 	}
1351 
1352 	/*
1353 	 * If this dataset is not currently an encryption root we need a new
1354 	 * keylocation for this dataset's new wrapping key. Otherwise we can
1355 	 * just keep the one we already had.
1356 	 */
1357 	if (dd->dd_object != rddobj && dcp->cp_keylocation == NULL) {
1358 		ret = SET_ERROR(EINVAL);
1359 		goto error;
1360 	}
1361 
1362 	/* check that the keylocation is valid if it is not NULL */
1363 	if (dcp->cp_keylocation != NULL &&
1364 	    !zfs_prop_valid_keylocation(dcp->cp_keylocation, B_TRUE)) {
1365 		ret = SET_ERROR(EINVAL);
1366 		goto error;
1367 	}
1368 
1369 	/* passphrases require pbkdf2 salt and iters */
1370 	if (dcp->cp_wkey->wk_keyformat == ZFS_KEYFORMAT_PASSPHRASE) {
1371 		if (dcp->cp_wkey->wk_salt == 0 ||
1372 		    dcp->cp_wkey->wk_iters < MIN_PBKDF2_ITERATIONS) {
1373 			ret = SET_ERROR(EINVAL);
1374 			goto error;
1375 		}
1376 	} else {
1377 		if (dcp->cp_wkey->wk_salt != 0 || dcp->cp_wkey->wk_iters != 0) {
1378 			ret = SET_ERROR(EINVAL);
1379 			goto error;
1380 		}
1381 	}
1382 
1383 	/* make sure the dd's wkey is loaded */
1384 	ret = dmu_objset_check_wkey_loaded(dd);
1385 	if (ret != 0)
1386 		goto error;
1387 
1388 	dsl_dir_rele(dd, FTAG);
1389 
1390 	return (0);
1391 
1392 error:
1393 	if (dd != NULL)
1394 		dsl_dir_rele(dd, FTAG);
1395 
1396 	return (ret);
1397 }
1398 
1399 /*
1400  * This function deals with the intricacies of updating wrapping
1401  * key references and encryption roots recursively in the event
1402  * of a call to 'zfs change-key' or 'zfs promote'. The 'skip'
1403  * parameter should always be set to B_FALSE when called
1404  * externally.
1405  */
1406 static void
1407 spa_keystore_change_key_sync_impl(uint64_t rddobj, uint64_t ddobj,
1408     uint64_t new_rddobj, dsl_wrapping_key_t *wkey, boolean_t skip,
1409     dmu_tx_t *tx)
1410 {
1411 	int ret;
1412 	zap_cursor_t *zc;
1413 	zap_attribute_t *za;
1414 	dsl_pool_t *dp = dmu_tx_pool(tx);
1415 	dsl_dir_t *dd = NULL;
1416 	dsl_crypto_key_t *dck = NULL;
1417 	uint64_t curr_rddobj;
1418 
1419 	ASSERT(RW_WRITE_HELD(&dp->dp_spa->spa_keystore.sk_wkeys_lock));
1420 
1421 	/* hold the dd */
1422 	VERIFY0(dsl_dir_hold_obj(dp, ddobj, NULL, FTAG, &dd));
1423 
1424 	/* ignore special dsl dirs */
1425 	if (dd->dd_myname[0] == '$' || dd->dd_myname[0] == '%') {
1426 		dsl_dir_rele(dd, FTAG);
1427 		return;
1428 	}
1429 
1430 	ret = dsl_dir_get_encryption_root_ddobj(dd, &curr_rddobj);
1431 	VERIFY(ret == 0 || ret == ENOENT);
1432 
1433 	/*
1434 	 * Stop recursing if this dsl dir didn't inherit from the root
1435 	 * or if this dd is a clone.
1436 	 */
1437 	if (ret == ENOENT ||
1438 	    (!skip && (curr_rddobj != rddobj || dsl_dir_is_clone(dd)))) {
1439 		dsl_dir_rele(dd, FTAG);
1440 		return;
1441 	}
1442 
1443 	/*
1444 	 * If we don't have a wrapping key just update the dck to reflect the
1445 	 * new encryption root. Otherwise rewrap the entire dck and re-sync it
1446 	 * to disk. If skip is set, we don't do any of this work.
1447 	 */
1448 	if (!skip) {
1449 		if (wkey == NULL) {
1450 			VERIFY0(zap_update(dp->dp_meta_objset,
1451 			    dd->dd_crypto_obj,
1452 			    DSL_CRYPTO_KEY_ROOT_DDOBJ, 8, 1,
1453 			    &new_rddobj, tx));
1454 		} else {
1455 			VERIFY0(spa_keystore_dsl_key_hold_dd(dp->dp_spa, dd,
1456 			    FTAG, &dck));
1457 			dsl_wrapping_key_hold(wkey, dck);
1458 			dsl_wrapping_key_rele(dck->dck_wkey, dck);
1459 			dck->dck_wkey = wkey;
1460 			dsl_crypto_key_sync(dck, tx);
1461 			spa_keystore_dsl_key_rele(dp->dp_spa, dck, FTAG);
1462 		}
1463 	}
1464 
1465 	zc = kmem_alloc(sizeof (zap_cursor_t), KM_SLEEP);
1466 	za = kmem_alloc(sizeof (zap_attribute_t), KM_SLEEP);
1467 
1468 	/* Recurse into all child dsl dirs. */
1469 	for (zap_cursor_init(zc, dp->dp_meta_objset,
1470 	    dsl_dir_phys(dd)->dd_child_dir_zapobj);
1471 	    zap_cursor_retrieve(zc, za) == 0;
1472 	    zap_cursor_advance(zc)) {
1473 		spa_keystore_change_key_sync_impl(rddobj,
1474 		    za->za_first_integer, new_rddobj, wkey, B_FALSE, tx);
1475 	}
1476 	zap_cursor_fini(zc);
1477 
1478 	/*
1479 	 * Recurse into all dsl dirs of clones. We utilize the skip parameter
1480 	 * here so that we don't attempt to process the clones directly. This
1481 	 * is because the clone and its origin share the same dck, which has
1482 	 * already been updated.
1483 	 */
1484 	for (zap_cursor_init(zc, dp->dp_meta_objset,
1485 	    dsl_dir_phys(dd)->dd_clones);
1486 	    zap_cursor_retrieve(zc, za) == 0;
1487 	    zap_cursor_advance(zc)) {
1488 		dsl_dataset_t *clone;
1489 
1490 		VERIFY0(dsl_dataset_hold_obj(dp, za->za_first_integer,
1491 		    FTAG, &clone));
1492 		spa_keystore_change_key_sync_impl(rddobj,
1493 		    clone->ds_dir->dd_object, new_rddobj, wkey, B_TRUE, tx);
1494 		dsl_dataset_rele(clone, FTAG);
1495 	}
1496 	zap_cursor_fini(zc);
1497 
1498 	kmem_free(za, sizeof (zap_attribute_t));
1499 	kmem_free(zc, sizeof (zap_cursor_t));
1500 
1501 	dsl_dir_rele(dd, FTAG);
1502 }
1503 
1504 static void
1505 spa_keystore_change_key_sync(void *arg, dmu_tx_t *tx)
1506 {
1507 	dsl_dataset_t *ds;
1508 	avl_index_t where;
1509 	dsl_pool_t *dp = dmu_tx_pool(tx);
1510 	spa_t *spa = dp->dp_spa;
1511 	spa_keystore_change_key_args_t *skcka = arg;
1512 	dsl_crypto_params_t *dcp = skcka->skcka_cp;
1513 	dsl_wrapping_key_t *wkey = NULL, *found_wkey;
1514 	dsl_wrapping_key_t wkey_search;
1515 	const char *keylocation = dcp->cp_keylocation;
1516 	uint64_t rddobj, new_rddobj;
1517 
1518 	/* create and initialize the wrapping key */
1519 	VERIFY0(dsl_dataset_hold(dp, skcka->skcka_dsname, FTAG, &ds));
1520 	ASSERT(!ds->ds_is_snapshot);
1521 
1522 	if (dcp->cp_cmd == DCP_CMD_NEW_KEY ||
1523 	    dcp->cp_cmd == DCP_CMD_FORCE_NEW_KEY) {
1524 		/*
1525 		 * We are changing to a new wkey. Set additional properties
1526 		 * which can be sent along with this ioctl. Note that this
1527 		 * command can set keylocation even if it can't normally be
1528 		 * set via 'zfs set' due to a non-local keylocation.
1529 		 */
1530 		if (dcp->cp_cmd == DCP_CMD_NEW_KEY) {
1531 			wkey = dcp->cp_wkey;
1532 			wkey->wk_ddobj = ds->ds_dir->dd_object;
1533 		} else {
1534 			keylocation = "prompt";
1535 		}
1536 
1537 		if (keylocation != NULL) {
1538 			dsl_prop_set_sync_impl(ds,
1539 			    zfs_prop_to_name(ZFS_PROP_KEYLOCATION),
1540 			    ZPROP_SRC_LOCAL, 1, strlen(keylocation) + 1,
1541 			    keylocation, tx);
1542 		}
1543 
1544 		VERIFY0(dsl_dir_get_encryption_root_ddobj(ds->ds_dir, &rddobj));
1545 		new_rddobj = ds->ds_dir->dd_object;
1546 	} else {
1547 		/*
1548 		 * We are inheritting the parent's wkey. Unset any local
1549 		 * keylocation and grab a reference to the wkey.
1550 		 */
1551 		if (dcp->cp_cmd == DCP_CMD_INHERIT) {
1552 			VERIFY0(spa_keystore_wkey_hold_dd(spa,
1553 			    ds->ds_dir->dd_parent, FTAG, &wkey));
1554 		}
1555 
1556 		dsl_prop_set_sync_impl(ds,
1557 		    zfs_prop_to_name(ZFS_PROP_KEYLOCATION), ZPROP_SRC_NONE,
1558 		    0, 0, NULL, tx);
1559 
1560 		rddobj = ds->ds_dir->dd_object;
1561 		VERIFY0(dsl_dir_get_encryption_root_ddobj(ds->ds_dir->dd_parent,
1562 		    &new_rddobj));
1563 	}
1564 
1565 	if (wkey == NULL) {
1566 		ASSERT(dcp->cp_cmd == DCP_CMD_FORCE_INHERIT ||
1567 		    dcp->cp_cmd == DCP_CMD_FORCE_NEW_KEY);
1568 	}
1569 
1570 	rw_enter(&spa->spa_keystore.sk_wkeys_lock, RW_WRITER);
1571 
1572 	/* recurse through all children and rewrap their keys */
1573 	spa_keystore_change_key_sync_impl(rddobj, ds->ds_dir->dd_object,
1574 	    new_rddobj, wkey, B_FALSE, tx);
1575 
1576 	/*
1577 	 * All references to the old wkey should be released now (if it
1578 	 * existed). Replace the wrapping key.
1579 	 */
1580 	wkey_search.wk_ddobj = ds->ds_dir->dd_object;
1581 	found_wkey = avl_find(&spa->spa_keystore.sk_wkeys, &wkey_search, NULL);
1582 	if (found_wkey != NULL) {
1583 		ASSERT0(zfs_refcount_count(&found_wkey->wk_refcnt));
1584 		avl_remove(&spa->spa_keystore.sk_wkeys, found_wkey);
1585 		dsl_wrapping_key_free(found_wkey);
1586 	}
1587 
1588 	if (dcp->cp_cmd == DCP_CMD_NEW_KEY) {
1589 		avl_find(&spa->spa_keystore.sk_wkeys, wkey, &where);
1590 		avl_insert(&spa->spa_keystore.sk_wkeys, wkey, where);
1591 	} else if (wkey != NULL) {
1592 		dsl_wrapping_key_rele(wkey, FTAG);
1593 	}
1594 
1595 	rw_exit(&spa->spa_keystore.sk_wkeys_lock);
1596 
1597 	dsl_dataset_rele(ds, FTAG);
1598 }
1599 
1600 int
1601 spa_keystore_change_key(const char *dsname, dsl_crypto_params_t *dcp)
1602 {
1603 	spa_keystore_change_key_args_t skcka;
1604 
1605 	/* initialize the args struct */
1606 	skcka.skcka_dsname = dsname;
1607 	skcka.skcka_cp = dcp;
1608 
1609 	/*
1610 	 * Perform the actual work in syncing context. The blocks modified
1611 	 * here could be calculated but it would require holding the pool
1612 	 * lock and traversing all of the datasets that will have their keys
1613 	 * changed.
1614 	 */
1615 	return (dsl_sync_task(dsname, spa_keystore_change_key_check,
1616 	    spa_keystore_change_key_sync, &skcka, 15,
1617 	    ZFS_SPACE_CHECK_RESERVED));
1618 }
1619 
1620 int
1621 dsl_dir_rename_crypt_check(dsl_dir_t *dd, dsl_dir_t *newparent)
1622 {
1623 	int ret;
1624 	uint64_t curr_rddobj, parent_rddobj;
1625 
1626 	if (dd->dd_crypto_obj == 0)
1627 		return (0);
1628 
1629 	ret = dsl_dir_get_encryption_root_ddobj(dd, &curr_rddobj);
1630 	if (ret != 0)
1631 		goto error;
1632 
1633 	/*
1634 	 * if this is not an encryption root, we must make sure we are not
1635 	 * moving dd to a new encryption root
1636 	 */
1637 	if (dd->dd_object != curr_rddobj) {
1638 		ret = dsl_dir_get_encryption_root_ddobj(newparent,
1639 		    &parent_rddobj);
1640 		if (ret != 0)
1641 			goto error;
1642 
1643 		if (parent_rddobj != curr_rddobj) {
1644 			ret = SET_ERROR(EACCES);
1645 			goto error;
1646 		}
1647 	}
1648 
1649 	return (0);
1650 
1651 error:
1652 	return (ret);
1653 }
1654 
1655 /*
1656  * Check to make sure that a promote from targetdd to origindd will not require
1657  * any key rewraps.
1658  */
1659 int
1660 dsl_dataset_promote_crypt_check(dsl_dir_t *target, dsl_dir_t *origin)
1661 {
1662 	int ret;
1663 	uint64_t rddobj, op_rddobj, tp_rddobj;
1664 
1665 	/* If the dataset is not encrypted we don't need to check anything */
1666 	if (origin->dd_crypto_obj == 0)
1667 		return (0);
1668 
1669 	/*
1670 	 * If we are not changing the first origin snapshot in a chain
1671 	 * the encryption root won't change either.
1672 	 */
1673 	if (dsl_dir_is_clone(origin))
1674 		return (0);
1675 
1676 	/*
1677 	 * If the origin is the encryption root we will update
1678 	 * the DSL Crypto Key to point to the target instead.
1679 	 */
1680 	ret = dsl_dir_get_encryption_root_ddobj(origin, &rddobj);
1681 	if (ret != 0)
1682 		return (ret);
1683 
1684 	if (rddobj == origin->dd_object)
1685 		return (0);
1686 
1687 	/*
1688 	 * The origin is inheriting its encryption root from its parent.
1689 	 * Check that the parent of the target has the same encryption root.
1690 	 */
1691 	ret = dsl_dir_get_encryption_root_ddobj(origin->dd_parent, &op_rddobj);
1692 	if (ret == ENOENT)
1693 		return (SET_ERROR(EACCES));
1694 	else if (ret != 0)
1695 		return (ret);
1696 
1697 	ret = dsl_dir_get_encryption_root_ddobj(target->dd_parent, &tp_rddobj);
1698 	if (ret == ENOENT)
1699 		return (SET_ERROR(EACCES));
1700 	else if (ret != 0)
1701 		return (ret);
1702 
1703 	if (op_rddobj != tp_rddobj)
1704 		return (SET_ERROR(EACCES));
1705 
1706 	return (0);
1707 }
1708 
1709 void
1710 dsl_dataset_promote_crypt_sync(dsl_dir_t *target, dsl_dir_t *origin,
1711     dmu_tx_t *tx)
1712 {
1713 	uint64_t rddobj;
1714 	dsl_pool_t *dp = target->dd_pool;
1715 	dsl_dataset_t *targetds;
1716 	dsl_dataset_t *originds;
1717 	char *keylocation;
1718 
1719 	if (origin->dd_crypto_obj == 0)
1720 		return;
1721 	if (dsl_dir_is_clone(origin))
1722 		return;
1723 
1724 	VERIFY0(dsl_dir_get_encryption_root_ddobj(origin, &rddobj));
1725 
1726 	if (rddobj != origin->dd_object)
1727 		return;
1728 
1729 	/*
1730 	 * If the target is being promoted to the encryption root update the
1731 	 * DSL Crypto Key and keylocation to reflect that. We also need to
1732 	 * update the DSL Crypto Keys of all children inheritting their
1733 	 * encryption root to point to the new target. Otherwise, the check
1734 	 * function ensured that the encryption root will not change.
1735 	 */
1736 	keylocation = kmem_alloc(ZAP_MAXVALUELEN, KM_SLEEP);
1737 
1738 	VERIFY0(dsl_dataset_hold_obj(dp,
1739 	    dsl_dir_phys(target)->dd_head_dataset_obj, FTAG, &targetds));
1740 	VERIFY0(dsl_dataset_hold_obj(dp,
1741 	    dsl_dir_phys(origin)->dd_head_dataset_obj, FTAG, &originds));
1742 
1743 	VERIFY0(dsl_prop_get_dd(origin, zfs_prop_to_name(ZFS_PROP_KEYLOCATION),
1744 	    1, ZAP_MAXVALUELEN, keylocation, NULL, B_FALSE));
1745 	dsl_prop_set_sync_impl(targetds, zfs_prop_to_name(ZFS_PROP_KEYLOCATION),
1746 	    ZPROP_SRC_LOCAL, 1, strlen(keylocation) + 1, keylocation, tx);
1747 	dsl_prop_set_sync_impl(originds, zfs_prop_to_name(ZFS_PROP_KEYLOCATION),
1748 	    ZPROP_SRC_NONE, 0, 0, NULL, tx);
1749 
1750 	rw_enter(&dp->dp_spa->spa_keystore.sk_wkeys_lock, RW_WRITER);
1751 	spa_keystore_change_key_sync_impl(rddobj, origin->dd_object,
1752 	    target->dd_object, NULL, B_FALSE, tx);
1753 	rw_exit(&dp->dp_spa->spa_keystore.sk_wkeys_lock);
1754 
1755 	dsl_dataset_rele(targetds, FTAG);
1756 	dsl_dataset_rele(originds, FTAG);
1757 	kmem_free(keylocation, ZAP_MAXVALUELEN);
1758 }
1759 
1760 int
1761 dmu_objset_create_crypt_check(dsl_dir_t *parentdd, dsl_crypto_params_t *dcp,
1762     boolean_t *will_encrypt)
1763 {
1764 	int ret;
1765 	uint64_t pcrypt, crypt;
1766 	dsl_crypto_params_t dummy_dcp = { 0 };
1767 
1768 	if (will_encrypt != NULL)
1769 		*will_encrypt = B_FALSE;
1770 
1771 	if (dcp == NULL)
1772 		dcp = &dummy_dcp;
1773 
1774 	if (dcp->cp_cmd != DCP_CMD_NONE)
1775 		return (SET_ERROR(EINVAL));
1776 
1777 	if (parentdd != NULL) {
1778 		ret = dsl_dir_get_crypt(parentdd, &pcrypt);
1779 		if (ret != 0)
1780 			return (ret);
1781 	} else {
1782 		pcrypt = ZIO_CRYPT_OFF;
1783 	}
1784 
1785 	crypt = (dcp->cp_crypt == ZIO_CRYPT_INHERIT) ? pcrypt : dcp->cp_crypt;
1786 
1787 	ASSERT3U(pcrypt, !=, ZIO_CRYPT_INHERIT);
1788 	ASSERT3U(crypt, !=, ZIO_CRYPT_INHERIT);
1789 
1790 	/* check for valid dcp with no encryption (inherited or local) */
1791 	if (crypt == ZIO_CRYPT_OFF) {
1792 		/* Must not specify encryption params */
1793 		if (dcp->cp_wkey != NULL ||
1794 		    (dcp->cp_keylocation != NULL &&
1795 		    strcmp(dcp->cp_keylocation, "none") != 0))
1796 			return (SET_ERROR(EINVAL));
1797 
1798 		return (0);
1799 	}
1800 
1801 	if (will_encrypt != NULL)
1802 		*will_encrypt = B_TRUE;
1803 
1804 	/*
1805 	 * We will now definitely be encrypting. Check the feature flag. When
1806 	 * creating the pool the caller will check this for us since we won't
1807 	 * technically have the feature activated yet.
1808 	 */
1809 	if (parentdd != NULL &&
1810 	    !spa_feature_is_enabled(parentdd->dd_pool->dp_spa,
1811 	    SPA_FEATURE_ENCRYPTION)) {
1812 		return (SET_ERROR(EOPNOTSUPP));
1813 	}
1814 
1815 	/* Check for errata #4 (encryption enabled, bookmark_v2 disabled) */
1816 	if (parentdd != NULL &&
1817 	    !spa_feature_is_enabled(parentdd->dd_pool->dp_spa,
1818 	    SPA_FEATURE_BOOKMARK_V2)) {
1819 		return (SET_ERROR(EOPNOTSUPP));
1820 	}
1821 
1822 	/* handle inheritance */
1823 	if (dcp->cp_wkey == NULL) {
1824 		ASSERT3P(parentdd, !=, NULL);
1825 
1826 		/* key must be fully unspecified */
1827 		if (dcp->cp_keylocation != NULL)
1828 			return (SET_ERROR(EINVAL));
1829 
1830 		/* parent must have a key to inherit */
1831 		if (pcrypt == ZIO_CRYPT_OFF)
1832 			return (SET_ERROR(EINVAL));
1833 
1834 		/* check for parent key */
1835 		ret = dmu_objset_check_wkey_loaded(parentdd);
1836 		if (ret != 0)
1837 			return (ret);
1838 
1839 		return (0);
1840 	}
1841 
1842 	/* At this point we should have a fully specified key. Check location */
1843 	if (dcp->cp_keylocation == NULL ||
1844 	    !zfs_prop_valid_keylocation(dcp->cp_keylocation, B_TRUE))
1845 		return (SET_ERROR(EINVAL));
1846 
1847 	/* Must have fully specified keyformat */
1848 	switch (dcp->cp_wkey->wk_keyformat) {
1849 	case ZFS_KEYFORMAT_HEX:
1850 	case ZFS_KEYFORMAT_RAW:
1851 		/* requires no pbkdf2 iters and salt */
1852 		if (dcp->cp_wkey->wk_salt != 0 || dcp->cp_wkey->wk_iters != 0)
1853 			return (SET_ERROR(EINVAL));
1854 		break;
1855 	case ZFS_KEYFORMAT_PASSPHRASE:
1856 		/* requires pbkdf2 iters and salt */
1857 		if (dcp->cp_wkey->wk_salt == 0 ||
1858 		    dcp->cp_wkey->wk_iters < MIN_PBKDF2_ITERATIONS)
1859 			return (SET_ERROR(EINVAL));
1860 		break;
1861 	case ZFS_KEYFORMAT_NONE:
1862 	default:
1863 		/* keyformat must be specified and valid */
1864 		return (SET_ERROR(EINVAL));
1865 	}
1866 
1867 	return (0);
1868 }
1869 
1870 void
1871 dsl_dataset_create_crypt_sync(uint64_t dsobj, dsl_dir_t *dd,
1872     dsl_dataset_t *origin, dsl_crypto_params_t *dcp, dmu_tx_t *tx)
1873 {
1874 	dsl_pool_t *dp = dd->dd_pool;
1875 	uint64_t crypt;
1876 	dsl_wrapping_key_t *wkey;
1877 
1878 	/* clones always use their origin's wrapping key */
1879 	if (dsl_dir_is_clone(dd)) {
1880 		ASSERT3P(dcp, ==, NULL);
1881 
1882 		/*
1883 		 * If this is an encrypted clone we just need to clone the
1884 		 * dck into dd. Zapify the dd so we can do that.
1885 		 */
1886 		if (origin->ds_dir->dd_crypto_obj != 0) {
1887 			dmu_buf_will_dirty(dd->dd_dbuf, tx);
1888 			dsl_dir_zapify(dd, tx);
1889 
1890 			dd->dd_crypto_obj =
1891 			    dsl_crypto_key_clone_sync(origin->ds_dir, tx);
1892 			VERIFY0(zap_add(dp->dp_meta_objset, dd->dd_object,
1893 			    DD_FIELD_CRYPTO_KEY_OBJ, sizeof (uint64_t), 1,
1894 			    &dd->dd_crypto_obj, tx));
1895 		}
1896 
1897 		return;
1898 	}
1899 
1900 	/*
1901 	 * A NULL dcp at this point indicates this is the origin dataset
1902 	 * which does not have an objset to encrypt. Raw receives will handle
1903 	 * encryption separately later. In both cases we can simply return.
1904 	 */
1905 	if (dcp == NULL || dcp->cp_cmd == DCP_CMD_RAW_RECV)
1906 		return;
1907 
1908 	crypt = dcp->cp_crypt;
1909 	wkey = dcp->cp_wkey;
1910 
1911 	/* figure out the effective crypt */
1912 	if (crypt == ZIO_CRYPT_INHERIT && dd->dd_parent != NULL)
1913 		VERIFY0(dsl_dir_get_crypt(dd->dd_parent, &crypt));
1914 
1915 	/* if we aren't doing encryption just return */
1916 	if (crypt == ZIO_CRYPT_OFF || crypt == ZIO_CRYPT_INHERIT)
1917 		return;
1918 
1919 	/* zapify the dd so that we can add the crypto key obj to it */
1920 	dmu_buf_will_dirty(dd->dd_dbuf, tx);
1921 	dsl_dir_zapify(dd, tx);
1922 
1923 	/* use the new key if given or inherit from the parent */
1924 	if (wkey == NULL) {
1925 		VERIFY0(spa_keystore_wkey_hold_dd(dp->dp_spa,
1926 		    dd->dd_parent, FTAG, &wkey));
1927 	} else {
1928 		wkey->wk_ddobj = dd->dd_object;
1929 	}
1930 
1931 	ASSERT3P(wkey, !=, NULL);
1932 
1933 	/* Create or clone the DSL crypto key and activate the feature */
1934 	dd->dd_crypto_obj = dsl_crypto_key_create_sync(crypt, wkey, tx);
1935 	VERIFY0(zap_add(dp->dp_meta_objset, dd->dd_object,
1936 	    DD_FIELD_CRYPTO_KEY_OBJ, sizeof (uint64_t), 1, &dd->dd_crypto_obj,
1937 	    tx));
1938 	dsl_dataset_activate_feature(dsobj, SPA_FEATURE_ENCRYPTION,
1939 	    (void *)B_TRUE, tx);
1940 
1941 	/*
1942 	 * If we inherited the wrapping key we release our reference now.
1943 	 * Otherwise, this is a new key and we need to load it into the
1944 	 * keystore.
1945 	 */
1946 	if (dcp->cp_wkey == NULL) {
1947 		dsl_wrapping_key_rele(wkey, FTAG);
1948 	} else {
1949 		VERIFY0(spa_keystore_load_wkey_impl(dp->dp_spa, wkey));
1950 	}
1951 }
1952 
1953 typedef struct dsl_crypto_recv_key_arg {
1954 	uint64_t dcrka_dsobj;
1955 	uint64_t dcrka_fromobj;
1956 	dmu_objset_type_t dcrka_ostype;
1957 	nvlist_t *dcrka_nvl;
1958 	boolean_t dcrka_do_key;
1959 } dsl_crypto_recv_key_arg_t;
1960 
1961 static int
1962 dsl_crypto_recv_raw_objset_check(dsl_dataset_t *ds, dsl_dataset_t *fromds,
1963     dmu_objset_type_t ostype, nvlist_t *nvl, dmu_tx_t *tx)
1964 {
1965 	int ret;
1966 	objset_t *os;
1967 	dnode_t *mdn;
1968 	uint8_t *buf = NULL;
1969 	uint_t len;
1970 	uint64_t intval, nlevels, blksz, ibs;
1971 	uint64_t nblkptr, maxblkid;
1972 
1973 	if (ostype != DMU_OST_ZFS && ostype != DMU_OST_ZVOL)
1974 		return (SET_ERROR(EINVAL));
1975 
1976 	/* raw receives also need info about the structure of the metadnode */
1977 	ret = nvlist_lookup_uint64(nvl, "mdn_compress", &intval);
1978 	if (ret != 0 || intval >= ZIO_COMPRESS_LEGACY_FUNCTIONS)
1979 		return (SET_ERROR(EINVAL));
1980 
1981 	ret = nvlist_lookup_uint64(nvl, "mdn_checksum", &intval);
1982 	if (ret != 0 || intval >= ZIO_CHECKSUM_LEGACY_FUNCTIONS)
1983 		return (SET_ERROR(EINVAL));
1984 
1985 	ret = nvlist_lookup_uint64(nvl, "mdn_nlevels", &nlevels);
1986 	if (ret != 0 || nlevels > DN_MAX_LEVELS)
1987 		return (SET_ERROR(EINVAL));
1988 
1989 	ret = nvlist_lookup_uint64(nvl, "mdn_blksz", &blksz);
1990 	if (ret != 0 || blksz < SPA_MINBLOCKSIZE)
1991 		return (SET_ERROR(EINVAL));
1992 	else if (blksz > spa_maxblocksize(tx->tx_pool->dp_spa))
1993 		return (SET_ERROR(ENOTSUP));
1994 
1995 	ret = nvlist_lookup_uint64(nvl, "mdn_indblkshift", &ibs);
1996 	if (ret != 0 || ibs < DN_MIN_INDBLKSHIFT || ibs > DN_MAX_INDBLKSHIFT)
1997 		return (SET_ERROR(ENOTSUP));
1998 
1999 	ret = nvlist_lookup_uint64(nvl, "mdn_nblkptr", &nblkptr);
2000 	if (ret != 0 || nblkptr != DN_MAX_NBLKPTR)
2001 		return (SET_ERROR(ENOTSUP));
2002 
2003 	ret = nvlist_lookup_uint64(nvl, "mdn_maxblkid", &maxblkid);
2004 	if (ret != 0)
2005 		return (SET_ERROR(EINVAL));
2006 
2007 	ret = nvlist_lookup_uint8_array(nvl, "portable_mac", &buf, &len);
2008 	if (ret != 0 || len != ZIO_OBJSET_MAC_LEN)
2009 		return (SET_ERROR(EINVAL));
2010 
2011 	ret = dmu_objset_from_ds(ds, &os);
2012 	if (ret != 0)
2013 		return (ret);
2014 
2015 	mdn = DMU_META_DNODE(os);
2016 
2017 	/*
2018 	 * If we already created the objset, make sure its unchangeable
2019 	 * properties match the ones received in the nvlist.
2020 	 */
2021 	rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG);
2022 	if (!BP_IS_HOLE(dsl_dataset_get_blkptr(ds)) &&
2023 	    (mdn->dn_nlevels != nlevels || mdn->dn_datablksz != blksz ||
2024 	    mdn->dn_indblkshift != ibs || mdn->dn_nblkptr != nblkptr)) {
2025 		rrw_exit(&ds->ds_bp_rwlock, FTAG);
2026 		return (SET_ERROR(EINVAL));
2027 	}
2028 	rrw_exit(&ds->ds_bp_rwlock, FTAG);
2029 
2030 	/*
2031 	 * Check that the ivset guid of the fromds matches the one from the
2032 	 * send stream. Older versions of the encryption code did not have
2033 	 * an ivset guid on the from dataset and did not send one in the
2034 	 * stream. For these streams we provide the
2035 	 * zfs_disable_ivset_guid_check tunable to allow these datasets to
2036 	 * be received with a generated ivset guid.
2037 	 */
2038 	if (fromds != NULL && !zfs_disable_ivset_guid_check) {
2039 		uint64_t from_ivset_guid = 0;
2040 		intval = 0;
2041 
2042 		(void) nvlist_lookup_uint64(nvl, "from_ivset_guid", &intval);
2043 		(void) zap_lookup(tx->tx_pool->dp_meta_objset,
2044 		    fromds->ds_object, DS_FIELD_IVSET_GUID,
2045 		    sizeof (from_ivset_guid), 1, &from_ivset_guid);
2046 
2047 		if (intval == 0 || from_ivset_guid == 0)
2048 			return (SET_ERROR(ZFS_ERR_FROM_IVSET_GUID_MISSING));
2049 
2050 		if (intval != from_ivset_guid)
2051 			return (SET_ERROR(ZFS_ERR_FROM_IVSET_GUID_MISMATCH));
2052 	}
2053 
2054 	return (0);
2055 }
2056 
2057 static void
2058 dsl_crypto_recv_raw_objset_sync(dsl_dataset_t *ds, dmu_objset_type_t ostype,
2059     nvlist_t *nvl, dmu_tx_t *tx)
2060 {
2061 	dsl_pool_t *dp = tx->tx_pool;
2062 	objset_t *os;
2063 	dnode_t *mdn;
2064 	zio_t *zio;
2065 	uint8_t *portable_mac;
2066 	uint_t len;
2067 	uint64_t compress, checksum, nlevels, blksz, ibs, maxblkid;
2068 	boolean_t newds = B_FALSE;
2069 
2070 	VERIFY0(dmu_objset_from_ds(ds, &os));
2071 	mdn = DMU_META_DNODE(os);
2072 
2073 	/*
2074 	 * Fetch the values we need from the nvlist. "to_ivset_guid" must
2075 	 * be set on the snapshot, which doesn't exist yet. The receive
2076 	 * code will take care of this for us later.
2077 	 */
2078 	compress = fnvlist_lookup_uint64(nvl, "mdn_compress");
2079 	checksum = fnvlist_lookup_uint64(nvl, "mdn_checksum");
2080 	nlevels = fnvlist_lookup_uint64(nvl, "mdn_nlevels");
2081 	blksz = fnvlist_lookup_uint64(nvl, "mdn_blksz");
2082 	ibs = fnvlist_lookup_uint64(nvl, "mdn_indblkshift");
2083 	maxblkid = fnvlist_lookup_uint64(nvl, "mdn_maxblkid");
2084 	VERIFY0(nvlist_lookup_uint8_array(nvl, "portable_mac", &portable_mac,
2085 	    &len));
2086 
2087 	/* if we haven't created an objset for the ds yet, do that now */
2088 	rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG);
2089 	if (BP_IS_HOLE(dsl_dataset_get_blkptr(ds))) {
2090 		(void) dmu_objset_create_impl_dnstats(dp->dp_spa, ds,
2091 		    dsl_dataset_get_blkptr(ds), ostype, nlevels, blksz,
2092 		    ibs, tx);
2093 		newds = B_TRUE;
2094 	}
2095 	rrw_exit(&ds->ds_bp_rwlock, FTAG);
2096 
2097 	/*
2098 	 * Set the portable MAC. The local MAC will always be zero since the
2099 	 * incoming data will all be portable and user accounting will be
2100 	 * deferred until the next mount. Afterwards, flag the os to be
2101 	 * written out raw next time.
2102 	 */
2103 	arc_release(os->os_phys_buf, &os->os_phys_buf);
2104 	memcpy(os->os_phys->os_portable_mac, portable_mac, ZIO_OBJSET_MAC_LEN);
2105 	memset(os->os_phys->os_local_mac, 0, ZIO_OBJSET_MAC_LEN);
2106 	os->os_flags &= ~OBJSET_FLAG_USERACCOUNTING_COMPLETE;
2107 	os->os_next_write_raw[tx->tx_txg & TXG_MASK] = B_TRUE;
2108 
2109 	/* set metadnode compression and checksum */
2110 	mdn->dn_compress = compress;
2111 	mdn->dn_checksum = checksum;
2112 
2113 	rw_enter(&mdn->dn_struct_rwlock, RW_WRITER);
2114 	dnode_new_blkid(mdn, maxblkid, tx, B_FALSE, B_TRUE);
2115 	rw_exit(&mdn->dn_struct_rwlock);
2116 
2117 	/*
2118 	 * We can't normally dirty the dataset in syncing context unless
2119 	 * we are creating a new dataset. In this case, we perform a
2120 	 * pseudo txg sync here instead.
2121 	 */
2122 	if (newds) {
2123 		dsl_dataset_dirty(ds, tx);
2124 	} else {
2125 		zio = zio_root(dp->dp_spa, NULL, NULL, ZIO_FLAG_MUSTSUCCEED);
2126 		dsl_dataset_sync(ds, zio, tx);
2127 		VERIFY0(zio_wait(zio));
2128 		dsl_dataset_sync_done(ds, tx);
2129 	}
2130 }
2131 
2132 int
2133 dsl_crypto_recv_raw_key_check(dsl_dataset_t *ds, nvlist_t *nvl, dmu_tx_t *tx)
2134 {
2135 	int ret;
2136 	objset_t *mos = tx->tx_pool->dp_meta_objset;
2137 	uint8_t *buf = NULL;
2138 	uint_t len;
2139 	uint64_t intval, key_guid, version;
2140 	boolean_t is_passphrase = B_FALSE;
2141 
2142 	ASSERT(dsl_dataset_phys(ds)->ds_flags & DS_FLAG_INCONSISTENT);
2143 
2144 	/*
2145 	 * Read and check all the encryption values from the nvlist. We need
2146 	 * all of the fields of a DSL Crypto Key, as well as a fully specified
2147 	 * wrapping key.
2148 	 */
2149 	ret = nvlist_lookup_uint64(nvl, DSL_CRYPTO_KEY_CRYPTO_SUITE, &intval);
2150 	if (ret != 0 || intval <= ZIO_CRYPT_OFF)
2151 		return (SET_ERROR(EINVAL));
2152 
2153 	/*
2154 	 * Flag a future crypto suite that we don't support differently, so
2155 	 * we can return a more useful error to the user.
2156 	 */
2157 	if (intval >= ZIO_CRYPT_FUNCTIONS)
2158 		return (SET_ERROR(ZFS_ERR_CRYPTO_NOTSUP));
2159 
2160 	ret = nvlist_lookup_uint64(nvl, DSL_CRYPTO_KEY_GUID, &intval);
2161 	if (ret != 0)
2162 		return (SET_ERROR(EINVAL));
2163 
2164 	/*
2165 	 * If this is an incremental receive make sure the given key guid
2166 	 * matches the one we already have.
2167 	 */
2168 	if (ds->ds_dir->dd_crypto_obj != 0) {
2169 		ret = zap_lookup(mos, ds->ds_dir->dd_crypto_obj,
2170 		    DSL_CRYPTO_KEY_GUID, 8, 1, &key_guid);
2171 		if (ret != 0)
2172 			return (ret);
2173 		if (intval != key_guid)
2174 			return (SET_ERROR(EACCES));
2175 	}
2176 
2177 	ret = nvlist_lookup_uint8_array(nvl, DSL_CRYPTO_KEY_MASTER_KEY,
2178 	    &buf, &len);
2179 	if (ret != 0 || len != MASTER_KEY_MAX_LEN)
2180 		return (SET_ERROR(EINVAL));
2181 
2182 	ret = nvlist_lookup_uint8_array(nvl, DSL_CRYPTO_KEY_HMAC_KEY,
2183 	    &buf, &len);
2184 	if (ret != 0 || len != SHA512_HMAC_KEYLEN)
2185 		return (SET_ERROR(EINVAL));
2186 
2187 	ret = nvlist_lookup_uint8_array(nvl, DSL_CRYPTO_KEY_IV, &buf, &len);
2188 	if (ret != 0 || len != WRAPPING_IV_LEN)
2189 		return (SET_ERROR(EINVAL));
2190 
2191 	ret = nvlist_lookup_uint8_array(nvl, DSL_CRYPTO_KEY_MAC, &buf, &len);
2192 	if (ret != 0 || len != WRAPPING_MAC_LEN)
2193 		return (SET_ERROR(EINVAL));
2194 
2195 	/*
2196 	 * We don't support receiving old on-disk formats. The version 0
2197 	 * implementation protected several fields in an objset that were
2198 	 * not always portable during a raw receive. As a result, we call
2199 	 * the old version an on-disk errata #3.
2200 	 */
2201 	ret = nvlist_lookup_uint64(nvl, DSL_CRYPTO_KEY_VERSION, &version);
2202 	if (ret != 0 || version != ZIO_CRYPT_KEY_CURRENT_VERSION)
2203 		return (SET_ERROR(ENOTSUP));
2204 
2205 	ret = nvlist_lookup_uint64(nvl, zfs_prop_to_name(ZFS_PROP_KEYFORMAT),
2206 	    &intval);
2207 	if (ret != 0 || intval >= ZFS_KEYFORMAT_FORMATS ||
2208 	    intval == ZFS_KEYFORMAT_NONE)
2209 		return (SET_ERROR(EINVAL));
2210 
2211 	is_passphrase = (intval == ZFS_KEYFORMAT_PASSPHRASE);
2212 
2213 	/*
2214 	 * for raw receives we allow any number of pbkdf2iters since there
2215 	 * won't be a chance for the user to change it.
2216 	 */
2217 	ret = nvlist_lookup_uint64(nvl, zfs_prop_to_name(ZFS_PROP_PBKDF2_ITERS),
2218 	    &intval);
2219 	if (ret != 0 || (is_passphrase == (intval == 0)))
2220 		return (SET_ERROR(EINVAL));
2221 
2222 	ret = nvlist_lookup_uint64(nvl, zfs_prop_to_name(ZFS_PROP_PBKDF2_SALT),
2223 	    &intval);
2224 	if (ret != 0 || (is_passphrase == (intval == 0)))
2225 		return (SET_ERROR(EINVAL));
2226 
2227 	return (0);
2228 }
2229 
2230 void
2231 dsl_crypto_recv_raw_key_sync(dsl_dataset_t *ds, nvlist_t *nvl, dmu_tx_t *tx)
2232 {
2233 	dsl_pool_t *dp = tx->tx_pool;
2234 	objset_t *mos = dp->dp_meta_objset;
2235 	dsl_dir_t *dd = ds->ds_dir;
2236 	uint_t len;
2237 	uint64_t rddobj, one = 1;
2238 	uint8_t *keydata, *hmac_keydata, *iv, *mac;
2239 	uint64_t crypt, key_guid, keyformat, iters, salt;
2240 	uint64_t version = ZIO_CRYPT_KEY_CURRENT_VERSION;
2241 	const char *keylocation = "prompt";
2242 
2243 	/* lookup the values we need to create the DSL Crypto Key */
2244 	crypt = fnvlist_lookup_uint64(nvl, DSL_CRYPTO_KEY_CRYPTO_SUITE);
2245 	key_guid = fnvlist_lookup_uint64(nvl, DSL_CRYPTO_KEY_GUID);
2246 	keyformat = fnvlist_lookup_uint64(nvl,
2247 	    zfs_prop_to_name(ZFS_PROP_KEYFORMAT));
2248 	iters = fnvlist_lookup_uint64(nvl,
2249 	    zfs_prop_to_name(ZFS_PROP_PBKDF2_ITERS));
2250 	salt = fnvlist_lookup_uint64(nvl,
2251 	    zfs_prop_to_name(ZFS_PROP_PBKDF2_SALT));
2252 	VERIFY0(nvlist_lookup_uint8_array(nvl, DSL_CRYPTO_KEY_MASTER_KEY,
2253 	    &keydata, &len));
2254 	VERIFY0(nvlist_lookup_uint8_array(nvl, DSL_CRYPTO_KEY_HMAC_KEY,
2255 	    &hmac_keydata, &len));
2256 	VERIFY0(nvlist_lookup_uint8_array(nvl, DSL_CRYPTO_KEY_IV, &iv, &len));
2257 	VERIFY0(nvlist_lookup_uint8_array(nvl, DSL_CRYPTO_KEY_MAC, &mac, &len));
2258 
2259 	/* if this is a new dataset setup the DSL Crypto Key. */
2260 	if (dd->dd_crypto_obj == 0) {
2261 		/* zapify the dsl dir so we can add the key object to it */
2262 		dmu_buf_will_dirty(dd->dd_dbuf, tx);
2263 		dsl_dir_zapify(dd, tx);
2264 
2265 		/* create the DSL Crypto Key on disk and activate the feature */
2266 		dd->dd_crypto_obj = zap_create(mos,
2267 		    DMU_OTN_ZAP_METADATA, DMU_OT_NONE, 0, tx);
2268 		VERIFY0(zap_update(tx->tx_pool->dp_meta_objset,
2269 		    dd->dd_crypto_obj, DSL_CRYPTO_KEY_REFCOUNT,
2270 		    sizeof (uint64_t), 1, &one, tx));
2271 		VERIFY0(zap_update(tx->tx_pool->dp_meta_objset,
2272 		    dd->dd_crypto_obj, DSL_CRYPTO_KEY_VERSION,
2273 		    sizeof (uint64_t), 1, &version, tx));
2274 
2275 		dsl_dataset_activate_feature(ds->ds_object,
2276 		    SPA_FEATURE_ENCRYPTION, (void *)B_TRUE, tx);
2277 		ds->ds_feature[SPA_FEATURE_ENCRYPTION] = (void *)B_TRUE;
2278 
2279 		/* save the dd_crypto_obj on disk */
2280 		VERIFY0(zap_add(mos, dd->dd_object, DD_FIELD_CRYPTO_KEY_OBJ,
2281 		    sizeof (uint64_t), 1, &dd->dd_crypto_obj, tx));
2282 
2283 		/*
2284 		 * Set the keylocation to prompt by default. If keylocation
2285 		 * has been provided via the properties, this will be overridden
2286 		 * later.
2287 		 */
2288 		dsl_prop_set_sync_impl(ds,
2289 		    zfs_prop_to_name(ZFS_PROP_KEYLOCATION),
2290 		    ZPROP_SRC_LOCAL, 1, strlen(keylocation) + 1,
2291 		    keylocation, tx);
2292 
2293 		rddobj = dd->dd_object;
2294 	} else {
2295 		VERIFY0(dsl_dir_get_encryption_root_ddobj(dd, &rddobj));
2296 	}
2297 
2298 	/* sync the key data to the ZAP object on disk */
2299 	dsl_crypto_key_sync_impl(mos, dd->dd_crypto_obj, crypt,
2300 	    rddobj, key_guid, iv, mac, keydata, hmac_keydata, keyformat, salt,
2301 	    iters, tx);
2302 }
2303 
2304 static int
2305 dsl_crypto_recv_key_check(void *arg, dmu_tx_t *tx)
2306 {
2307 	int ret;
2308 	dsl_crypto_recv_key_arg_t *dcrka = arg;
2309 	dsl_dataset_t *ds = NULL, *fromds = NULL;
2310 
2311 	ret = dsl_dataset_hold_obj(tx->tx_pool, dcrka->dcrka_dsobj,
2312 	    FTAG, &ds);
2313 	if (ret != 0)
2314 		goto out;
2315 
2316 	if (dcrka->dcrka_fromobj != 0) {
2317 		ret = dsl_dataset_hold_obj(tx->tx_pool, dcrka->dcrka_fromobj,
2318 		    FTAG, &fromds);
2319 		if (ret != 0)
2320 			goto out;
2321 	}
2322 
2323 	ret = dsl_crypto_recv_raw_objset_check(ds, fromds,
2324 	    dcrka->dcrka_ostype, dcrka->dcrka_nvl, tx);
2325 	if (ret != 0)
2326 		goto out;
2327 
2328 	/*
2329 	 * We run this check even if we won't be doing this part of
2330 	 * the receive now so that we don't make the user wait until
2331 	 * the receive finishes to fail.
2332 	 */
2333 	ret = dsl_crypto_recv_raw_key_check(ds, dcrka->dcrka_nvl, tx);
2334 	if (ret != 0)
2335 		goto out;
2336 
2337 out:
2338 	if (ds != NULL)
2339 		dsl_dataset_rele(ds, FTAG);
2340 	if (fromds != NULL)
2341 		dsl_dataset_rele(fromds, FTAG);
2342 	return (ret);
2343 }
2344 
2345 static void
2346 dsl_crypto_recv_key_sync(void *arg, dmu_tx_t *tx)
2347 {
2348 	dsl_crypto_recv_key_arg_t *dcrka = arg;
2349 	dsl_dataset_t *ds;
2350 
2351 	VERIFY0(dsl_dataset_hold_obj(tx->tx_pool, dcrka->dcrka_dsobj,
2352 	    FTAG, &ds));
2353 	dsl_crypto_recv_raw_objset_sync(ds, dcrka->dcrka_ostype,
2354 	    dcrka->dcrka_nvl, tx);
2355 	if (dcrka->dcrka_do_key)
2356 		dsl_crypto_recv_raw_key_sync(ds, dcrka->dcrka_nvl, tx);
2357 	dsl_dataset_rele(ds, FTAG);
2358 }
2359 
2360 /*
2361  * This function is used to sync an nvlist representing a DSL Crypto Key and
2362  * the associated encryption parameters. The key will be written exactly as is
2363  * without wrapping it.
2364  */
2365 int
2366 dsl_crypto_recv_raw(const char *poolname, uint64_t dsobj, uint64_t fromobj,
2367     dmu_objset_type_t ostype, nvlist_t *nvl, boolean_t do_key)
2368 {
2369 	dsl_crypto_recv_key_arg_t dcrka;
2370 
2371 	dcrka.dcrka_dsobj = dsobj;
2372 	dcrka.dcrka_fromobj = fromobj;
2373 	dcrka.dcrka_ostype = ostype;
2374 	dcrka.dcrka_nvl = nvl;
2375 	dcrka.dcrka_do_key = do_key;
2376 
2377 	return (dsl_sync_task(poolname, dsl_crypto_recv_key_check,
2378 	    dsl_crypto_recv_key_sync, &dcrka, 1, ZFS_SPACE_CHECK_NORMAL));
2379 }
2380 
2381 int
2382 dsl_crypto_populate_key_nvlist(objset_t *os, uint64_t from_ivset_guid,
2383     nvlist_t **nvl_out)
2384 {
2385 	int ret;
2386 	dsl_dataset_t *ds = os->os_dsl_dataset;
2387 	dnode_t *mdn;
2388 	uint64_t rddobj;
2389 	nvlist_t *nvl = NULL;
2390 	uint64_t dckobj = ds->ds_dir->dd_crypto_obj;
2391 	dsl_dir_t *rdd = NULL;
2392 	dsl_pool_t *dp = ds->ds_dir->dd_pool;
2393 	objset_t *mos = dp->dp_meta_objset;
2394 	uint64_t crypt = 0, key_guid = 0, format = 0;
2395 	uint64_t iters = 0, salt = 0, version = 0;
2396 	uint64_t to_ivset_guid = 0;
2397 	uint8_t raw_keydata[MASTER_KEY_MAX_LEN];
2398 	uint8_t raw_hmac_keydata[SHA512_HMAC_KEYLEN];
2399 	uint8_t iv[WRAPPING_IV_LEN];
2400 	uint8_t mac[WRAPPING_MAC_LEN];
2401 
2402 	ASSERT(dckobj != 0);
2403 
2404 	mdn = DMU_META_DNODE(os);
2405 
2406 	nvl = fnvlist_alloc();
2407 
2408 	/* lookup values from the DSL Crypto Key */
2409 	ret = zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_CRYPTO_SUITE, 8, 1,
2410 	    &crypt);
2411 	if (ret != 0)
2412 		goto error;
2413 
2414 	ret = zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_GUID, 8, 1, &key_guid);
2415 	if (ret != 0)
2416 		goto error;
2417 
2418 	ret = zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_MASTER_KEY, 1,
2419 	    MASTER_KEY_MAX_LEN, raw_keydata);
2420 	if (ret != 0)
2421 		goto error;
2422 
2423 	ret = zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_HMAC_KEY, 1,
2424 	    SHA512_HMAC_KEYLEN, raw_hmac_keydata);
2425 	if (ret != 0)
2426 		goto error;
2427 
2428 	ret = zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_IV, 1, WRAPPING_IV_LEN,
2429 	    iv);
2430 	if (ret != 0)
2431 		goto error;
2432 
2433 	ret = zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_MAC, 1, WRAPPING_MAC_LEN,
2434 	    mac);
2435 	if (ret != 0)
2436 		goto error;
2437 
2438 	/* see zfs_disable_ivset_guid_check tunable for errata info */
2439 	ret = zap_lookup(mos, ds->ds_object, DS_FIELD_IVSET_GUID, 8, 1,
2440 	    &to_ivset_guid);
2441 	if (ret != 0)
2442 		ASSERT3U(dp->dp_spa->spa_errata, !=, 0);
2443 
2444 	/*
2445 	 * We don't support raw sends of legacy on-disk formats. See the
2446 	 * comment in dsl_crypto_recv_key_check() for details.
2447 	 */
2448 	ret = zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_VERSION, 8, 1, &version);
2449 	if (ret != 0 || version != ZIO_CRYPT_KEY_CURRENT_VERSION) {
2450 		dp->dp_spa->spa_errata = ZPOOL_ERRATA_ZOL_6845_ENCRYPTION;
2451 		ret = SET_ERROR(ENOTSUP);
2452 		goto error;
2453 	}
2454 
2455 	/*
2456 	 * Lookup wrapping key properties. An early version of the code did
2457 	 * not correctly add these values to the wrapping key or the DSL
2458 	 * Crypto Key on disk for non encryption roots, so to be safe we
2459 	 * always take the slightly circuitous route of looking it up from
2460 	 * the encryption root's key.
2461 	 */
2462 	ret = dsl_dir_get_encryption_root_ddobj(ds->ds_dir, &rddobj);
2463 	if (ret != 0)
2464 		goto error;
2465 
2466 	dsl_pool_config_enter(dp, FTAG);
2467 
2468 	ret = dsl_dir_hold_obj(dp, rddobj, NULL, FTAG, &rdd);
2469 	if (ret != 0)
2470 		goto error_unlock;
2471 
2472 	ret = zap_lookup(dp->dp_meta_objset, rdd->dd_crypto_obj,
2473 	    zfs_prop_to_name(ZFS_PROP_KEYFORMAT), 8, 1, &format);
2474 	if (ret != 0)
2475 		goto error_unlock;
2476 
2477 	if (format == ZFS_KEYFORMAT_PASSPHRASE) {
2478 		ret = zap_lookup(dp->dp_meta_objset, rdd->dd_crypto_obj,
2479 		    zfs_prop_to_name(ZFS_PROP_PBKDF2_ITERS), 8, 1, &iters);
2480 		if (ret != 0)
2481 			goto error_unlock;
2482 
2483 		ret = zap_lookup(dp->dp_meta_objset, rdd->dd_crypto_obj,
2484 		    zfs_prop_to_name(ZFS_PROP_PBKDF2_SALT), 8, 1, &salt);
2485 		if (ret != 0)
2486 			goto error_unlock;
2487 	}
2488 
2489 	dsl_dir_rele(rdd, FTAG);
2490 	dsl_pool_config_exit(dp, FTAG);
2491 
2492 	fnvlist_add_uint64(nvl, DSL_CRYPTO_KEY_CRYPTO_SUITE, crypt);
2493 	fnvlist_add_uint64(nvl, DSL_CRYPTO_KEY_GUID, key_guid);
2494 	fnvlist_add_uint64(nvl, DSL_CRYPTO_KEY_VERSION, version);
2495 	VERIFY0(nvlist_add_uint8_array(nvl, DSL_CRYPTO_KEY_MASTER_KEY,
2496 	    raw_keydata, MASTER_KEY_MAX_LEN));
2497 	VERIFY0(nvlist_add_uint8_array(nvl, DSL_CRYPTO_KEY_HMAC_KEY,
2498 	    raw_hmac_keydata, SHA512_HMAC_KEYLEN));
2499 	VERIFY0(nvlist_add_uint8_array(nvl, DSL_CRYPTO_KEY_IV, iv,
2500 	    WRAPPING_IV_LEN));
2501 	VERIFY0(nvlist_add_uint8_array(nvl, DSL_CRYPTO_KEY_MAC, mac,
2502 	    WRAPPING_MAC_LEN));
2503 	VERIFY0(nvlist_add_uint8_array(nvl, "portable_mac",
2504 	    os->os_phys->os_portable_mac, ZIO_OBJSET_MAC_LEN));
2505 	fnvlist_add_uint64(nvl, zfs_prop_to_name(ZFS_PROP_KEYFORMAT), format);
2506 	fnvlist_add_uint64(nvl, zfs_prop_to_name(ZFS_PROP_PBKDF2_ITERS), iters);
2507 	fnvlist_add_uint64(nvl, zfs_prop_to_name(ZFS_PROP_PBKDF2_SALT), salt);
2508 	fnvlist_add_uint64(nvl, "mdn_checksum", mdn->dn_checksum);
2509 	fnvlist_add_uint64(nvl, "mdn_compress", mdn->dn_compress);
2510 	fnvlist_add_uint64(nvl, "mdn_nlevels", mdn->dn_nlevels);
2511 	fnvlist_add_uint64(nvl, "mdn_blksz", mdn->dn_datablksz);
2512 	fnvlist_add_uint64(nvl, "mdn_indblkshift", mdn->dn_indblkshift);
2513 	fnvlist_add_uint64(nvl, "mdn_nblkptr", mdn->dn_nblkptr);
2514 	fnvlist_add_uint64(nvl, "mdn_maxblkid", mdn->dn_maxblkid);
2515 	fnvlist_add_uint64(nvl, "to_ivset_guid", to_ivset_guid);
2516 	fnvlist_add_uint64(nvl, "from_ivset_guid", from_ivset_guid);
2517 
2518 	*nvl_out = nvl;
2519 	return (0);
2520 
2521 error_unlock:
2522 	dsl_pool_config_exit(dp, FTAG);
2523 error:
2524 	if (rdd != NULL)
2525 		dsl_dir_rele(rdd, FTAG);
2526 	nvlist_free(nvl);
2527 
2528 	*nvl_out = NULL;
2529 	return (ret);
2530 }
2531 
2532 uint64_t
2533 dsl_crypto_key_create_sync(uint64_t crypt, dsl_wrapping_key_t *wkey,
2534     dmu_tx_t *tx)
2535 {
2536 	dsl_crypto_key_t dck;
2537 	uint64_t version = ZIO_CRYPT_KEY_CURRENT_VERSION;
2538 	uint64_t one = 1ULL;
2539 
2540 	ASSERT(dmu_tx_is_syncing(tx));
2541 	ASSERT3U(crypt, <, ZIO_CRYPT_FUNCTIONS);
2542 	ASSERT3U(crypt, >, ZIO_CRYPT_OFF);
2543 
2544 	/* create the DSL Crypto Key ZAP object */
2545 	dck.dck_obj = zap_create(tx->tx_pool->dp_meta_objset,
2546 	    DMU_OTN_ZAP_METADATA, DMU_OT_NONE, 0, tx);
2547 
2548 	/* fill in the key (on the stack) and sync it to disk */
2549 	dck.dck_wkey = wkey;
2550 	VERIFY0(zio_crypt_key_init(crypt, &dck.dck_key));
2551 
2552 	dsl_crypto_key_sync(&dck, tx);
2553 	VERIFY0(zap_update(tx->tx_pool->dp_meta_objset, dck.dck_obj,
2554 	    DSL_CRYPTO_KEY_REFCOUNT, sizeof (uint64_t), 1, &one, tx));
2555 	VERIFY0(zap_update(tx->tx_pool->dp_meta_objset, dck.dck_obj,
2556 	    DSL_CRYPTO_KEY_VERSION, sizeof (uint64_t), 1, &version, tx));
2557 
2558 	zio_crypt_key_destroy(&dck.dck_key);
2559 	memset(&dck.dck_key, 0, sizeof (zio_crypt_key_t));
2560 
2561 	return (dck.dck_obj);
2562 }
2563 
2564 uint64_t
2565 dsl_crypto_key_clone_sync(dsl_dir_t *origindd, dmu_tx_t *tx)
2566 {
2567 	objset_t *mos = tx->tx_pool->dp_meta_objset;
2568 
2569 	ASSERT(dmu_tx_is_syncing(tx));
2570 
2571 	VERIFY0(zap_increment(mos, origindd->dd_crypto_obj,
2572 	    DSL_CRYPTO_KEY_REFCOUNT, 1, tx));
2573 
2574 	return (origindd->dd_crypto_obj);
2575 }
2576 
2577 void
2578 dsl_crypto_key_destroy_sync(uint64_t dckobj, dmu_tx_t *tx)
2579 {
2580 	objset_t *mos = tx->tx_pool->dp_meta_objset;
2581 	uint64_t refcnt;
2582 
2583 	/* Decrement the refcount, destroy if this is the last reference */
2584 	VERIFY0(zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_REFCOUNT,
2585 	    sizeof (uint64_t), 1, &refcnt));
2586 
2587 	if (refcnt != 1) {
2588 		VERIFY0(zap_increment(mos, dckobj, DSL_CRYPTO_KEY_REFCOUNT,
2589 		    -1, tx));
2590 	} else {
2591 		VERIFY0(zap_destroy(mos, dckobj, tx));
2592 	}
2593 }
2594 
2595 void
2596 dsl_dataset_crypt_stats(dsl_dataset_t *ds, nvlist_t *nv)
2597 {
2598 	uint64_t intval;
2599 	dsl_dir_t *dd = ds->ds_dir;
2600 	dsl_dir_t *enc_root;
2601 	char buf[ZFS_MAX_DATASET_NAME_LEN];
2602 
2603 	if (dd->dd_crypto_obj == 0)
2604 		return;
2605 
2606 	intval = dsl_dataset_get_keystatus(dd);
2607 	dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_KEYSTATUS, intval);
2608 
2609 	if (dsl_dir_get_crypt(dd, &intval) == 0)
2610 		dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_ENCRYPTION, intval);
2611 	if (zap_lookup(dd->dd_pool->dp_meta_objset, dd->dd_crypto_obj,
2612 	    DSL_CRYPTO_KEY_GUID, 8, 1, &intval) == 0) {
2613 		dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_KEY_GUID, intval);
2614 	}
2615 	if (zap_lookup(dd->dd_pool->dp_meta_objset, dd->dd_crypto_obj,
2616 	    zfs_prop_to_name(ZFS_PROP_KEYFORMAT), 8, 1, &intval) == 0) {
2617 		dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_KEYFORMAT, intval);
2618 	}
2619 	if (zap_lookup(dd->dd_pool->dp_meta_objset, dd->dd_crypto_obj,
2620 	    zfs_prop_to_name(ZFS_PROP_PBKDF2_SALT), 8, 1, &intval) == 0) {
2621 		dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_PBKDF2_SALT, intval);
2622 	}
2623 	if (zap_lookup(dd->dd_pool->dp_meta_objset, dd->dd_crypto_obj,
2624 	    zfs_prop_to_name(ZFS_PROP_PBKDF2_ITERS), 8, 1, &intval) == 0) {
2625 		dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_PBKDF2_ITERS, intval);
2626 	}
2627 	if (zap_lookup(dd->dd_pool->dp_meta_objset, ds->ds_object,
2628 	    DS_FIELD_IVSET_GUID, 8, 1, &intval) == 0) {
2629 		dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_IVSET_GUID, intval);
2630 	}
2631 
2632 	if (dsl_dir_get_encryption_root_ddobj(dd, &intval) == 0) {
2633 		if (dsl_dir_hold_obj(dd->dd_pool, intval, NULL, FTAG,
2634 		    &enc_root) == 0) {
2635 			dsl_dir_name(enc_root, buf);
2636 			dsl_dir_rele(enc_root, FTAG);
2637 			dsl_prop_nvlist_add_string(nv,
2638 			    ZFS_PROP_ENCRYPTION_ROOT, buf);
2639 		}
2640 	}
2641 }
2642 
2643 int
2644 spa_crypt_get_salt(spa_t *spa, uint64_t dsobj, uint8_t *salt)
2645 {
2646 	int ret;
2647 	dsl_crypto_key_t *dck = NULL;
2648 
2649 	/* look up the key from the spa's keystore */
2650 	ret = spa_keystore_lookup_key(spa, dsobj, FTAG, &dck);
2651 	if (ret != 0)
2652 		goto error;
2653 
2654 	ret = zio_crypt_key_get_salt(&dck->dck_key, salt);
2655 	if (ret != 0)
2656 		goto error;
2657 
2658 	spa_keystore_dsl_key_rele(spa, dck, FTAG);
2659 	return (0);
2660 
2661 error:
2662 	if (dck != NULL)
2663 		spa_keystore_dsl_key_rele(spa, dck, FTAG);
2664 	return (ret);
2665 }
2666 
2667 /*
2668  * Objset blocks are a special case for MAC generation. These blocks have 2
2669  * 256-bit MACs which are embedded within the block itself, rather than a
2670  * single 128 bit MAC. As a result, this function handles encoding and decoding
2671  * the MACs on its own, unlike other functions in this file.
2672  */
2673 int
2674 spa_do_crypt_objset_mac_abd(boolean_t generate, spa_t *spa, uint64_t dsobj,
2675     abd_t *abd, uint_t datalen, boolean_t byteswap)
2676 {
2677 	int ret;
2678 	dsl_crypto_key_t *dck = NULL;
2679 	void *buf = abd_borrow_buf_copy(abd, datalen);
2680 	objset_phys_t *osp = buf;
2681 	uint8_t portable_mac[ZIO_OBJSET_MAC_LEN];
2682 	uint8_t local_mac[ZIO_OBJSET_MAC_LEN];
2683 	const uint8_t zeroed_mac[ZIO_OBJSET_MAC_LEN] = {0};
2684 
2685 	/* look up the key from the spa's keystore */
2686 	ret = spa_keystore_lookup_key(spa, dsobj, FTAG, &dck);
2687 	if (ret != 0)
2688 		goto error;
2689 
2690 	/* calculate both HMACs */
2691 	ret = zio_crypt_do_objset_hmacs(&dck->dck_key, buf, datalen,
2692 	    byteswap, portable_mac, local_mac);
2693 	if (ret != 0)
2694 		goto error;
2695 
2696 	spa_keystore_dsl_key_rele(spa, dck, FTAG);
2697 
2698 	/* if we are generating encode the HMACs in the objset_phys_t */
2699 	if (generate) {
2700 		memcpy(osp->os_portable_mac, portable_mac, ZIO_OBJSET_MAC_LEN);
2701 		memcpy(osp->os_local_mac, local_mac, ZIO_OBJSET_MAC_LEN);
2702 		abd_return_buf_copy(abd, buf, datalen);
2703 		return (0);
2704 	}
2705 
2706 	if (memcmp(portable_mac, osp->os_portable_mac,
2707 	    ZIO_OBJSET_MAC_LEN) != 0 ||
2708 	    memcmp(local_mac, osp->os_local_mac, ZIO_OBJSET_MAC_LEN) != 0) {
2709 		/*
2710 		 * If the MAC is zeroed out, we failed to decrypt it.
2711 		 * This should only arise, at least on Linux,
2712 		 * if we hit edge case handling for useraccounting, since we
2713 		 * shouldn't get here without bailing out on error earlier
2714 		 * otherwise.
2715 		 *
2716 		 * So if we're in that case, we can just fall through and
2717 		 * special-casing noticing that it's zero will handle it
2718 		 * elsewhere, since we can just regenerate it.
2719 		 */
2720 		if (memcmp(local_mac, zeroed_mac, ZIO_OBJSET_MAC_LEN) != 0) {
2721 			abd_return_buf(abd, buf, datalen);
2722 			return (SET_ERROR(ECKSUM));
2723 		}
2724 	}
2725 
2726 	abd_return_buf(abd, buf, datalen);
2727 
2728 	return (0);
2729 
2730 error:
2731 	if (dck != NULL)
2732 		spa_keystore_dsl_key_rele(spa, dck, FTAG);
2733 	abd_return_buf(abd, buf, datalen);
2734 	return (ret);
2735 }
2736 
2737 int
2738 spa_do_crypt_mac_abd(boolean_t generate, spa_t *spa, uint64_t dsobj, abd_t *abd,
2739     uint_t datalen, uint8_t *mac)
2740 {
2741 	int ret;
2742 	dsl_crypto_key_t *dck = NULL;
2743 	uint8_t *buf = abd_borrow_buf_copy(abd, datalen);
2744 	uint8_t digestbuf[ZIO_DATA_MAC_LEN];
2745 
2746 	/* look up the key from the spa's keystore */
2747 	ret = spa_keystore_lookup_key(spa, dsobj, FTAG, &dck);
2748 	if (ret != 0)
2749 		goto error;
2750 
2751 	/* perform the hmac */
2752 	ret = zio_crypt_do_hmac(&dck->dck_key, buf, datalen,
2753 	    digestbuf, ZIO_DATA_MAC_LEN);
2754 	if (ret != 0)
2755 		goto error;
2756 
2757 	abd_return_buf(abd, buf, datalen);
2758 	spa_keystore_dsl_key_rele(spa, dck, FTAG);
2759 
2760 	/*
2761 	 * Truncate and fill in mac buffer if we were asked to generate a MAC.
2762 	 * Otherwise verify that the MAC matched what we expected.
2763 	 */
2764 	if (generate) {
2765 		memcpy(mac, digestbuf, ZIO_DATA_MAC_LEN);
2766 		return (0);
2767 	}
2768 
2769 	if (memcmp(digestbuf, mac, ZIO_DATA_MAC_LEN) != 0)
2770 		return (SET_ERROR(ECKSUM));
2771 
2772 	return (0);
2773 
2774 error:
2775 	if (dck != NULL)
2776 		spa_keystore_dsl_key_rele(spa, dck, FTAG);
2777 	abd_return_buf(abd, buf, datalen);
2778 	return (ret);
2779 }
2780 
2781 /*
2782  * This function serves as a multiplexer for encryption and decryption of
2783  * all blocks (except the L2ARC). For encryption, it will populate the IV,
2784  * salt, MAC, and cabd (the ciphertext). On decryption it will simply use
2785  * these fields to populate pabd (the plaintext).
2786  */
2787 int
2788 spa_do_crypt_abd(boolean_t encrypt, spa_t *spa, const zbookmark_phys_t *zb,
2789     dmu_object_type_t ot, boolean_t dedup, boolean_t bswap, uint8_t *salt,
2790     uint8_t *iv, uint8_t *mac, uint_t datalen, abd_t *pabd, abd_t *cabd,
2791     boolean_t *no_crypt)
2792 {
2793 	int ret;
2794 	dsl_crypto_key_t *dck = NULL;
2795 	uint8_t *plainbuf = NULL, *cipherbuf = NULL;
2796 
2797 	ASSERT(spa_feature_is_active(spa, SPA_FEATURE_ENCRYPTION));
2798 
2799 	/* look up the key from the spa's keystore */
2800 	ret = spa_keystore_lookup_key(spa, zb->zb_objset, FTAG, &dck);
2801 	if (ret != 0) {
2802 		ret = SET_ERROR(EACCES);
2803 		return (ret);
2804 	}
2805 
2806 	if (encrypt) {
2807 		plainbuf = abd_borrow_buf_copy(pabd, datalen);
2808 		cipherbuf = abd_borrow_buf(cabd, datalen);
2809 	} else {
2810 		plainbuf = abd_borrow_buf(pabd, datalen);
2811 		cipherbuf = abd_borrow_buf_copy(cabd, datalen);
2812 	}
2813 
2814 	/*
2815 	 * Both encryption and decryption functions need a salt for key
2816 	 * generation and an IV. When encrypting a non-dedup block, we
2817 	 * generate the salt and IV randomly to be stored by the caller. Dedup
2818 	 * blocks perform a (more expensive) HMAC of the plaintext to obtain
2819 	 * the salt and the IV. ZIL blocks have their salt and IV generated
2820 	 * at allocation time in zio_alloc_zil(). On decryption, we simply use
2821 	 * the provided values.
2822 	 */
2823 	if (encrypt && ot != DMU_OT_INTENT_LOG && !dedup) {
2824 		ret = zio_crypt_key_get_salt(&dck->dck_key, salt);
2825 		if (ret != 0)
2826 			goto error;
2827 
2828 		ret = zio_crypt_generate_iv(iv);
2829 		if (ret != 0)
2830 			goto error;
2831 	} else if (encrypt && dedup) {
2832 		ret = zio_crypt_generate_iv_salt_dedup(&dck->dck_key,
2833 		    plainbuf, datalen, iv, salt);
2834 		if (ret != 0)
2835 			goto error;
2836 	}
2837 
2838 	/* call lower level function to perform encryption / decryption */
2839 	ret = zio_do_crypt_data(encrypt, &dck->dck_key, ot, bswap, salt, iv,
2840 	    mac, datalen, plainbuf, cipherbuf, no_crypt);
2841 
2842 	/*
2843 	 * Handle injected decryption faults. Unfortunately, we cannot inject
2844 	 * faults for dnode blocks because we might trigger the panic in
2845 	 * dbuf_prepare_encrypted_dnode_leaf(), which exists because syncing
2846 	 * context is not prepared to handle malicious decryption failures.
2847 	 */
2848 	if (zio_injection_enabled && !encrypt && ot != DMU_OT_DNODE && ret == 0)
2849 		ret = zio_handle_decrypt_injection(spa, zb, ot, ECKSUM);
2850 	if (ret != 0)
2851 		goto error;
2852 
2853 	if (encrypt) {
2854 		abd_return_buf(pabd, plainbuf, datalen);
2855 		abd_return_buf_copy(cabd, cipherbuf, datalen);
2856 	} else {
2857 		abd_return_buf_copy(pabd, plainbuf, datalen);
2858 		abd_return_buf(cabd, cipherbuf, datalen);
2859 	}
2860 
2861 	spa_keystore_dsl_key_rele(spa, dck, FTAG);
2862 
2863 	return (0);
2864 
2865 error:
2866 	if (encrypt) {
2867 		/* zero out any state we might have changed while encrypting */
2868 		memset(salt, 0, ZIO_DATA_SALT_LEN);
2869 		memset(iv, 0, ZIO_DATA_IV_LEN);
2870 		memset(mac, 0, ZIO_DATA_MAC_LEN);
2871 		abd_return_buf(pabd, plainbuf, datalen);
2872 		abd_return_buf_copy(cabd, cipherbuf, datalen);
2873 	} else {
2874 		abd_return_buf_copy(pabd, plainbuf, datalen);
2875 		abd_return_buf(cabd, cipherbuf, datalen);
2876 	}
2877 
2878 	spa_keystore_dsl_key_rele(spa, dck, FTAG);
2879 
2880 	return (ret);
2881 }
2882 
2883 ZFS_MODULE_PARAM(zfs, zfs_, disable_ivset_guid_check, INT, ZMOD_RW,
2884 	"Set to allow raw receives without IVset guids");
2885