FreeBSD/Linux Kernel Cross Reference
sys/contrib/openzfs/module/zfs/dsl_crypt.c

     /*
      * CDDL HEADER START
      *
      * This file and its contents are supplied under the terms of the
      * Common Development and Distribution License ("CDDL"), version 1.0.
      * You may only use this file in accordance with the terms of version
      * 1.0 of the CDDL.
      *
      * A full copy of the text of the CDDL should have accompanied this
     * source.  A copy of the CDDL is also available via the Internet at
     * http://www.illumos.org/license/CDDL.
     *
     * CDDL HEADER END
     */
    
    /*
     * Copyright (c) 2017, Datto, Inc. All rights reserved.
     * Copyright (c) 2018 by Delphix. All rights reserved.
     */
    
    #include <sys/dsl_crypt.h>
    #include <sys/dsl_pool.h>
    #include <sys/zap.h>
    #include <sys/zil.h>
    #include <sys/dsl_dir.h>
    #include <sys/dsl_prop.h>
    #include <sys/spa_impl.h>
    #include <sys/dmu_objset.h>
    #include <sys/zvol.h>
    
    /*
     * This file's primary purpose is for managing master encryption keys in
     * memory and on disk. For more info on how these keys are used, see the
     * block comment in zio_crypt.c.
     *
     * All master keys are stored encrypted on disk in the form of the DSL
     * Crypto Key ZAP object. The binary key data in this object is always
     * randomly generated and is encrypted with the user's wrapping key. This
     * layer of indirection allows the user to change their key without
     * needing to re-encrypt the entire dataset. The ZAP also holds on to the
     * (non-encrypted) encryption algorithm identifier, IV, and MAC needed to
     * safely decrypt the master key. For more info on the user's key see the
     * block comment in libzfs_crypto.c
     *
     * In-memory encryption keys are managed through the spa_keystore. The
     * keystore consists of 3 AVL trees, which are as follows:
     *
     * The Wrapping Key Tree:
     * The wrapping key (wkey) tree stores the user's keys that are fed into the
     * kernel through 'zfs load-key' and related commands. Datasets inherit their
     * parent's wkey by default, so these structures are refcounted. The wrapping
     * keys remain in memory until they are explicitly unloaded (with
     * "zfs unload-key"). Unloading is only possible when no datasets are using
     * them (refcount=0).
     *
     * The DSL Crypto Key Tree:
     * The DSL Crypto Keys (DCK) are the in-memory representation of decrypted
     * master keys. They are used by the functions in zio_crypt.c to perform
     * encryption, decryption, and authentication. Snapshots and clones of a given
     * dataset will share a DSL Crypto Key, so they are also refcounted. Once the
     * refcount on a key hits zero, it is immediately zeroed out and freed.
     *
     * The Crypto Key Mapping Tree:
     * The zio layer needs to lookup master keys by their dataset object id. Since
     * the DSL Crypto Keys can belong to multiple datasets, we maintain a tree of
     * dsl_key_mapping_t's which essentially just map the dataset object id to its
     * appropriate DSL Crypto Key. The management for creating and destroying these
     * mappings hooks into the code for owning and disowning datasets. Usually,
     * there will only be one active dataset owner, but there are times
     * (particularly during dataset creation and destruction) when this may not be
     * true or the dataset may not be initialized enough to own. As a result, this
     * object is also refcounted.
     */
    
    /*
     * This tunable allows datasets to be raw received even if the stream does
     * not include IVset guids or if the guids don't match. This is used as part
     * of the resolution for ZPOOL_ERRATA_ZOL_8308_ENCRYPTION.
     */
    int zfs_disable_ivset_guid_check = 0;
    
    static void
    dsl_wrapping_key_hold(dsl_wrapping_key_t *wkey, const void *tag)
    {
            (void) zfs_refcount_add(&wkey->wk_refcnt, tag);
    }
    
    static void
    dsl_wrapping_key_rele(dsl_wrapping_key_t *wkey, const void *tag)
    {
            (void) zfs_refcount_remove(&wkey->wk_refcnt, tag);
    }
    
    static void
    dsl_wrapping_key_free(dsl_wrapping_key_t *wkey)
    {
            ASSERT0(zfs_refcount_count(&wkey->wk_refcnt));
    
            if (wkey->wk_key.ck_data) {
                   memset(wkey->wk_key.ck_data, 0,
                       CRYPTO_BITS2BYTES(wkey->wk_key.ck_length));
                   kmem_free(wkey->wk_key.ck_data,
                       CRYPTO_BITS2BYTES(wkey->wk_key.ck_length));
           }
   
           zfs_refcount_destroy(&wkey->wk_refcnt);
           kmem_free(wkey, sizeof (dsl_wrapping_key_t));
   }
   
   static void
   dsl_wrapping_key_create(uint8_t *wkeydata, zfs_keyformat_t keyformat,
       uint64_t salt, uint64_t iters, dsl_wrapping_key_t **wkey_out)
   {
           dsl_wrapping_key_t *wkey;
   
           /* allocate the wrapping key */
           wkey = kmem_alloc(sizeof (dsl_wrapping_key_t), KM_SLEEP);
   
           /* allocate and initialize the underlying crypto key */
           wkey->wk_key.ck_data = kmem_alloc(WRAPPING_KEY_LEN, KM_SLEEP);
   
           wkey->wk_key.ck_length = CRYPTO_BYTES2BITS(WRAPPING_KEY_LEN);
           memcpy(wkey->wk_key.ck_data, wkeydata, WRAPPING_KEY_LEN);
   
           /* initialize the rest of the struct */
           zfs_refcount_create(&wkey->wk_refcnt);
           wkey->wk_keyformat = keyformat;
           wkey->wk_salt = salt;
           wkey->wk_iters = iters;
   
           *wkey_out = wkey;
   }
   
   int
   dsl_crypto_params_create_nvlist(dcp_cmd_t cmd, nvlist_t *props,
       nvlist_t *crypto_args, dsl_crypto_params_t **dcp_out)
   {
           int ret;
           uint64_t crypt = ZIO_CRYPT_INHERIT;
           uint64_t keyformat = ZFS_KEYFORMAT_NONE;
           uint64_t salt = 0, iters = 0;
           dsl_crypto_params_t *dcp = NULL;
           dsl_wrapping_key_t *wkey = NULL;
           uint8_t *wkeydata = NULL;
           uint_t wkeydata_len = 0;
           char *keylocation = NULL;
   
           dcp = kmem_zalloc(sizeof (dsl_crypto_params_t), KM_SLEEP);
           dcp->cp_cmd = cmd;
   
           /* get relevant arguments from the nvlists */
           if (props != NULL) {
                   (void) nvlist_lookup_uint64(props,
                       zfs_prop_to_name(ZFS_PROP_ENCRYPTION), &crypt);
                   (void) nvlist_lookup_uint64(props,
                       zfs_prop_to_name(ZFS_PROP_KEYFORMAT), &keyformat);
                   (void) nvlist_lookup_string(props,
                       zfs_prop_to_name(ZFS_PROP_KEYLOCATION), &keylocation);
                   (void) nvlist_lookup_uint64(props,
                       zfs_prop_to_name(ZFS_PROP_PBKDF2_SALT), &salt);
                   (void) nvlist_lookup_uint64(props,
                       zfs_prop_to_name(ZFS_PROP_PBKDF2_ITERS), &iters);
   
                   dcp->cp_crypt = crypt;
           }
   
           if (crypto_args != NULL) {
                   (void) nvlist_lookup_uint8_array(crypto_args, "wkeydata",
                       &wkeydata, &wkeydata_len);
           }
   
           /* check for valid command */
           if (dcp->cp_cmd >= DCP_CMD_MAX) {
                   ret = SET_ERROR(EINVAL);
                   goto error;
           } else {
                   dcp->cp_cmd = cmd;
           }
   
           /* check for valid crypt */
           if (dcp->cp_crypt >= ZIO_CRYPT_FUNCTIONS) {
                   ret = SET_ERROR(EINVAL);
                   goto error;
           } else {
                   dcp->cp_crypt = crypt;
           }
   
           /* check for valid keyformat */
           if (keyformat >= ZFS_KEYFORMAT_FORMATS) {
                   ret = SET_ERROR(EINVAL);
                   goto error;
           }
   
           /* check for a valid keylocation (of any kind) and copy it in */
           if (keylocation != NULL) {
                   if (!zfs_prop_valid_keylocation(keylocation, B_FALSE)) {
                           ret = SET_ERROR(EINVAL);
                           goto error;
                   }
   
                   dcp->cp_keylocation = spa_strdup(keylocation);
           }
   
           /* check wrapping key length, if given */
           if (wkeydata != NULL && wkeydata_len != WRAPPING_KEY_LEN) {
                   ret = SET_ERROR(EINVAL);
                   goto error;
           }
   
           /* if the user asked for the default crypt, determine that now */
           if (dcp->cp_crypt == ZIO_CRYPT_ON)
                   dcp->cp_crypt = ZIO_CRYPT_ON_VALUE;
   
           /* create the wrapping key from the raw data */
           if (wkeydata != NULL) {
                   /* create the wrapping key with the verified parameters */
                   dsl_wrapping_key_create(wkeydata, keyformat, salt,
                       iters, &wkey);
                   dcp->cp_wkey = wkey;
           }
   
           /*
            * Remove the encryption properties from the nvlist since they are not
            * maintained through the DSL.
            */
           (void) nvlist_remove_all(props, zfs_prop_to_name(ZFS_PROP_ENCRYPTION));
           (void) nvlist_remove_all(props, zfs_prop_to_name(ZFS_PROP_KEYFORMAT));
           (void) nvlist_remove_all(props, zfs_prop_to_name(ZFS_PROP_PBKDF2_SALT));
           (void) nvlist_remove_all(props,
               zfs_prop_to_name(ZFS_PROP_PBKDF2_ITERS));
   
           *dcp_out = dcp;
   
           return (0);
   
   error:
           kmem_free(dcp, sizeof (dsl_crypto_params_t));
           *dcp_out = NULL;
           return (ret);
   }
   
   void
   dsl_crypto_params_free(dsl_crypto_params_t *dcp, boolean_t unload)
   {
           if (dcp == NULL)
                   return;
   
           if (dcp->cp_keylocation != NULL)
                   spa_strfree(dcp->cp_keylocation);
           if (unload && dcp->cp_wkey != NULL)
                   dsl_wrapping_key_free(dcp->cp_wkey);
   
           kmem_free(dcp, sizeof (dsl_crypto_params_t));
   }
   
   static int
   spa_crypto_key_compare(const void *a, const void *b)
   {
           const dsl_crypto_key_t *dcka = a;
           const dsl_crypto_key_t *dckb = b;
   
           if (dcka->dck_obj < dckb->dck_obj)
                   return (-1);
           if (dcka->dck_obj > dckb->dck_obj)
                   return (1);
           return (0);
   }
   
   static int
   spa_key_mapping_compare(const void *a, const void *b)
   {
           const dsl_key_mapping_t *kma = a;
           const dsl_key_mapping_t *kmb = b;
   
           if (kma->km_dsobj < kmb->km_dsobj)
                   return (-1);
           if (kma->km_dsobj > kmb->km_dsobj)
                   return (1);
           return (0);
   }
   
   static int
   spa_wkey_compare(const void *a, const void *b)
   {
           const dsl_wrapping_key_t *wka = a;
           const dsl_wrapping_key_t *wkb = b;
   
           if (wka->wk_ddobj < wkb->wk_ddobj)
                   return (-1);
           if (wka->wk_ddobj > wkb->wk_ddobj)
                   return (1);
           return (0);
   }
   
   void
   spa_keystore_init(spa_keystore_t *sk)
   {
           rw_init(&sk->sk_dk_lock, NULL, RW_DEFAULT, NULL);
           rw_init(&sk->sk_km_lock, NULL, RW_DEFAULT, NULL);
           rw_init(&sk->sk_wkeys_lock, NULL, RW_DEFAULT, NULL);
           avl_create(&sk->sk_dsl_keys, spa_crypto_key_compare,
               sizeof (dsl_crypto_key_t),
               offsetof(dsl_crypto_key_t, dck_avl_link));
           avl_create(&sk->sk_key_mappings, spa_key_mapping_compare,
               sizeof (dsl_key_mapping_t),
               offsetof(dsl_key_mapping_t, km_avl_link));
           avl_create(&sk->sk_wkeys, spa_wkey_compare, sizeof (dsl_wrapping_key_t),
               offsetof(dsl_wrapping_key_t, wk_avl_link));
   }
   
   void
   spa_keystore_fini(spa_keystore_t *sk)
   {
           dsl_wrapping_key_t *wkey;
           void *cookie = NULL;
   
           ASSERT(avl_is_empty(&sk->sk_dsl_keys));
           ASSERT(avl_is_empty(&sk->sk_key_mappings));
   
           while ((wkey = avl_destroy_nodes(&sk->sk_wkeys, &cookie)) != NULL)
                   dsl_wrapping_key_free(wkey);
   
           avl_destroy(&sk->sk_wkeys);
           avl_destroy(&sk->sk_key_mappings);
           avl_destroy(&sk->sk_dsl_keys);
           rw_destroy(&sk->sk_wkeys_lock);
           rw_destroy(&sk->sk_km_lock);
           rw_destroy(&sk->sk_dk_lock);
   }
   
   static int
   dsl_dir_get_encryption_root_ddobj(dsl_dir_t *dd, uint64_t *rddobj)
   {
           if (dd->dd_crypto_obj == 0)
                   return (SET_ERROR(ENOENT));
   
           return (zap_lookup(dd->dd_pool->dp_meta_objset, dd->dd_crypto_obj,
               DSL_CRYPTO_KEY_ROOT_DDOBJ, 8, 1, rddobj));
   }
   
   static int
   dsl_dir_get_encryption_version(dsl_dir_t *dd, uint64_t *version)
   {
           *version = 0;
   
           if (dd->dd_crypto_obj == 0)
                   return (SET_ERROR(ENOENT));
   
           /* version 0 is implied by ENOENT */
           (void) zap_lookup(dd->dd_pool->dp_meta_objset, dd->dd_crypto_obj,
               DSL_CRYPTO_KEY_VERSION, 8, 1, version);
   
           return (0);
   }
   
   boolean_t
   dsl_dir_incompatible_encryption_version(dsl_dir_t *dd)
   {
           int ret;
           uint64_t version = 0;
   
           ret = dsl_dir_get_encryption_version(dd, &version);
           if (ret != 0)
                   return (B_FALSE);
   
           return (version != ZIO_CRYPT_KEY_CURRENT_VERSION);
   }
   
   static int
   spa_keystore_wkey_hold_ddobj_impl(spa_t *spa, uint64_t ddobj,
       const void *tag, dsl_wrapping_key_t **wkey_out)
   {
           int ret;
           dsl_wrapping_key_t search_wkey;
           dsl_wrapping_key_t *found_wkey;
   
           ASSERT(RW_LOCK_HELD(&spa->spa_keystore.sk_wkeys_lock));
   
           /* init the search wrapping key */
           search_wkey.wk_ddobj = ddobj;
   
           /* lookup the wrapping key */
           found_wkey = avl_find(&spa->spa_keystore.sk_wkeys, &search_wkey, NULL);
           if (!found_wkey) {
                   ret = SET_ERROR(ENOENT);
                   goto error;
           }
   
           /* increment the refcount */
           dsl_wrapping_key_hold(found_wkey, tag);
   
           *wkey_out = found_wkey;
           return (0);
   
   error:
           *wkey_out = NULL;
           return (ret);
   }
   
   static int
   spa_keystore_wkey_hold_dd(spa_t *spa, dsl_dir_t *dd, const void *tag,
       dsl_wrapping_key_t **wkey_out)
   {
           int ret;
           dsl_wrapping_key_t *wkey;
           uint64_t rddobj;
           boolean_t locked = B_FALSE;
   
           if (!RW_WRITE_HELD(&spa->spa_keystore.sk_wkeys_lock)) {
                   rw_enter(&spa->spa_keystore.sk_wkeys_lock, RW_READER);
                   locked = B_TRUE;
           }
   
           /* get the ddobj that the keylocation property was inherited from */
           ret = dsl_dir_get_encryption_root_ddobj(dd, &rddobj);
           if (ret != 0)
                   goto error;
   
           /* lookup the wkey in the avl tree */
           ret = spa_keystore_wkey_hold_ddobj_impl(spa, rddobj, tag, &wkey);
           if (ret != 0)
                   goto error;
   
           /* unlock the wkey tree if we locked it */
           if (locked)
                   rw_exit(&spa->spa_keystore.sk_wkeys_lock);
   
           *wkey_out = wkey;
           return (0);
   
   error:
           if (locked)
                   rw_exit(&spa->spa_keystore.sk_wkeys_lock);
   
           *wkey_out = NULL;
           return (ret);
   }
   
   int
   dsl_crypto_can_set_keylocation(const char *dsname, const char *keylocation)
   {
           int ret = 0;
           dsl_dir_t *dd = NULL;
           dsl_pool_t *dp = NULL;
           uint64_t rddobj;
   
           /* hold the dsl dir */
           ret = dsl_pool_hold(dsname, FTAG, &dp);
           if (ret != 0)
                   goto out;
   
           ret = dsl_dir_hold(dp, dsname, FTAG, &dd, NULL);
           if (ret != 0) {
                   dd = NULL;
                   goto out;
           }
   
           /* if dd is not encrypted, the value may only be "none" */
           if (dd->dd_crypto_obj == 0) {
                   if (strcmp(keylocation, "none") != 0) {
                           ret = SET_ERROR(EACCES);
                           goto out;
                   }
   
                   ret = 0;
                   goto out;
           }
   
           /* check for a valid keylocation for encrypted datasets */
           if (!zfs_prop_valid_keylocation(keylocation, B_TRUE)) {
                   ret = SET_ERROR(EINVAL);
                   goto out;
           }
   
           /* check that this is an encryption root */
           ret = dsl_dir_get_encryption_root_ddobj(dd, &rddobj);
           if (ret != 0)
                   goto out;
   
           if (rddobj != dd->dd_object) {
                   ret = SET_ERROR(EACCES);
                   goto out;
           }
   
           dsl_dir_rele(dd, FTAG);
           dsl_pool_rele(dp, FTAG);
   
           return (0);
   
   out:
           if (dd != NULL)
                   dsl_dir_rele(dd, FTAG);
           if (dp != NULL)
                   dsl_pool_rele(dp, FTAG);
   
           return (ret);
   }
   
   static void
   dsl_crypto_key_free(dsl_crypto_key_t *dck)
   {
           ASSERT(zfs_refcount_count(&dck->dck_holds) == 0);
   
           /* destroy the zio_crypt_key_t */
           zio_crypt_key_destroy(&dck->dck_key);
   
           /* free the refcount, wrapping key, and lock */
           zfs_refcount_destroy(&dck->dck_holds);
           if (dck->dck_wkey)
                   dsl_wrapping_key_rele(dck->dck_wkey, dck);
   
           /* free the key */
           kmem_free(dck, sizeof (dsl_crypto_key_t));
   }
   
   static void
   dsl_crypto_key_rele(dsl_crypto_key_t *dck, const void *tag)
   {
           if (zfs_refcount_remove(&dck->dck_holds, tag) == 0)
                   dsl_crypto_key_free(dck);
   }
   
   static int
   dsl_crypto_key_open(objset_t *mos, dsl_wrapping_key_t *wkey,
       uint64_t dckobj, const void *tag, dsl_crypto_key_t **dck_out)
   {
           int ret;
           uint64_t crypt = 0, guid = 0, version = 0;
           uint8_t raw_keydata[MASTER_KEY_MAX_LEN];
           uint8_t raw_hmac_keydata[SHA512_HMAC_KEYLEN];
           uint8_t iv[WRAPPING_IV_LEN];
           uint8_t mac[WRAPPING_MAC_LEN];
           dsl_crypto_key_t *dck;
   
           /* allocate and initialize the key */
           dck = kmem_zalloc(sizeof (dsl_crypto_key_t), KM_SLEEP);
   
           /* fetch all of the values we need from the ZAP */
           ret = zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_CRYPTO_SUITE, 8, 1,
               &crypt);
           if (ret != 0)
                   goto error;
   
           ret = zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_GUID, 8, 1, &guid);
           if (ret != 0)
                   goto error;
   
           ret = zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_MASTER_KEY, 1,
               MASTER_KEY_MAX_LEN, raw_keydata);
           if (ret != 0)
                   goto error;
   
           ret = zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_HMAC_KEY, 1,
               SHA512_HMAC_KEYLEN, raw_hmac_keydata);
           if (ret != 0)
                   goto error;
   
           ret = zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_IV, 1, WRAPPING_IV_LEN,
               iv);
           if (ret != 0)
                   goto error;
   
           ret = zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_MAC, 1, WRAPPING_MAC_LEN,
               mac);
           if (ret != 0)
                   goto error;
   
           /* the initial on-disk format for encryption did not have a version */
           (void) zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_VERSION, 8, 1, &version);
   
           /*
            * Unwrap the keys. If there is an error return EACCES to indicate
            * an authentication failure.
            */
           ret = zio_crypt_key_unwrap(&wkey->wk_key, crypt, version, guid,
               raw_keydata, raw_hmac_keydata, iv, mac, &dck->dck_key);
           if (ret != 0) {
                   ret = SET_ERROR(EACCES);
                   goto error;
           }
   
           /* finish initializing the dsl_crypto_key_t */
           zfs_refcount_create(&dck->dck_holds);
           dsl_wrapping_key_hold(wkey, dck);
           dck->dck_wkey = wkey;
           dck->dck_obj = dckobj;
           zfs_refcount_add(&dck->dck_holds, tag);
   
           *dck_out = dck;
           return (0);
   
   error:
           if (dck != NULL) {
                   memset(dck, 0, sizeof (dsl_crypto_key_t));
                   kmem_free(dck, sizeof (dsl_crypto_key_t));
           }
   
           *dck_out = NULL;
           return (ret);
   }
   
   static int
   spa_keystore_dsl_key_hold_impl(spa_t *spa, uint64_t dckobj, const void *tag,
       dsl_crypto_key_t **dck_out)
   {
           int ret;
           dsl_crypto_key_t search_dck;
           dsl_crypto_key_t *found_dck;
   
           ASSERT(RW_LOCK_HELD(&spa->spa_keystore.sk_dk_lock));
   
           /* init the search key */
           search_dck.dck_obj = dckobj;
   
           /* find the matching key in the keystore */
           found_dck = avl_find(&spa->spa_keystore.sk_dsl_keys, &search_dck, NULL);
           if (!found_dck) {
                   ret = SET_ERROR(ENOENT);
                   goto error;
           }
   
           /* increment the refcount */
           zfs_refcount_add(&found_dck->dck_holds, tag);
   
           *dck_out = found_dck;
           return (0);
   
   error:
           *dck_out = NULL;
           return (ret);
   }
   
   static int
   spa_keystore_dsl_key_hold_dd(spa_t *spa, dsl_dir_t *dd, const void *tag,
       dsl_crypto_key_t **dck_out)
   {
           int ret;
           avl_index_t where;
           dsl_crypto_key_t *dck_io = NULL, *dck_ks = NULL;
           dsl_wrapping_key_t *wkey = NULL;
           uint64_t dckobj = dd->dd_crypto_obj;
   
           /* Lookup the key in the tree of currently loaded keys */
           rw_enter(&spa->spa_keystore.sk_dk_lock, RW_READER);
           ret = spa_keystore_dsl_key_hold_impl(spa, dckobj, tag, &dck_ks);
           rw_exit(&spa->spa_keystore.sk_dk_lock);
           if (ret == 0) {
                   *dck_out = dck_ks;
                   return (0);
           }
   
           /* Lookup the wrapping key from the keystore */
           ret = spa_keystore_wkey_hold_dd(spa, dd, FTAG, &wkey);
           if (ret != 0) {
                   *dck_out = NULL;
                   return (SET_ERROR(EACCES));
           }
   
           /* Read the key from disk */
           ret = dsl_crypto_key_open(spa->spa_meta_objset, wkey, dckobj,
               tag, &dck_io);
           if (ret != 0) {
                   dsl_wrapping_key_rele(wkey, FTAG);
                   *dck_out = NULL;
                   return (ret);
           }
   
           /*
            * Add the key to the keystore.  It may already exist if it was
            * added while performing the read from disk.  In this case discard
            * it and return the key from the keystore.
            */
           rw_enter(&spa->spa_keystore.sk_dk_lock, RW_WRITER);
           ret = spa_keystore_dsl_key_hold_impl(spa, dckobj, tag, &dck_ks);
           if (ret != 0) {
                   avl_find(&spa->spa_keystore.sk_dsl_keys, dck_io, &where);
                   avl_insert(&spa->spa_keystore.sk_dsl_keys, dck_io, where);
                   *dck_out = dck_io;
           } else {
                   dsl_crypto_key_free(dck_io);
                   *dck_out = dck_ks;
           }
   
           /* Release the wrapping key (the dsl key now has a reference to it) */
           dsl_wrapping_key_rele(wkey, FTAG);
           rw_exit(&spa->spa_keystore.sk_dk_lock);
   
           return (0);
   }
   
   void
   spa_keystore_dsl_key_rele(spa_t *spa, dsl_crypto_key_t *dck, const void *tag)
   {
           rw_enter(&spa->spa_keystore.sk_dk_lock, RW_WRITER);
   
           if (zfs_refcount_remove(&dck->dck_holds, tag) == 0) {
                   avl_remove(&spa->spa_keystore.sk_dsl_keys, dck);
                   dsl_crypto_key_free(dck);
           }
   
           rw_exit(&spa->spa_keystore.sk_dk_lock);
   }
   
   int
   spa_keystore_load_wkey_impl(spa_t *spa, dsl_wrapping_key_t *wkey)
   {
           int ret;
           avl_index_t where;
           dsl_wrapping_key_t *found_wkey;
   
           rw_enter(&spa->spa_keystore.sk_wkeys_lock, RW_WRITER);
   
           /* insert the wrapping key into the keystore */
           found_wkey = avl_find(&spa->spa_keystore.sk_wkeys, wkey, &where);
           if (found_wkey != NULL) {
                   ret = SET_ERROR(EEXIST);
                   goto error_unlock;
           }
           avl_insert(&spa->spa_keystore.sk_wkeys, wkey, where);
   
           rw_exit(&spa->spa_keystore.sk_wkeys_lock);
   
           return (0);
   
   error_unlock:
           rw_exit(&spa->spa_keystore.sk_wkeys_lock);
           return (ret);
   }
   
   int
   spa_keystore_load_wkey(const char *dsname, dsl_crypto_params_t *dcp,
       boolean_t noop)
   {
           int ret;
           dsl_dir_t *dd = NULL;
           dsl_crypto_key_t *dck = NULL;
           dsl_wrapping_key_t *wkey = dcp->cp_wkey;
           dsl_pool_t *dp = NULL;
           uint64_t rddobj, keyformat, salt, iters;
   
           /*
            * We don't validate the wrapping key's keyformat, salt, or iters
            * since they will never be needed after the DCK has been wrapped.
            */
           if (dcp->cp_wkey == NULL ||
               dcp->cp_cmd != DCP_CMD_NONE ||
               dcp->cp_crypt != ZIO_CRYPT_INHERIT ||
               dcp->cp_keylocation != NULL)
                   return (SET_ERROR(EINVAL));
   
           ret = dsl_pool_hold(dsname, FTAG, &dp);
           if (ret != 0)
                   goto error;
   
           if (!spa_feature_is_enabled(dp->dp_spa, SPA_FEATURE_ENCRYPTION)) {
                   ret = SET_ERROR(ENOTSUP);
                   goto error;
           }
   
           /* hold the dsl dir */
           ret = dsl_dir_hold(dp, dsname, FTAG, &dd, NULL);
           if (ret != 0) {
                   dd = NULL;
                   goto error;
           }
   
           /* confirm that dd is the encryption root */
           ret = dsl_dir_get_encryption_root_ddobj(dd, &rddobj);
           if (ret != 0 || rddobj != dd->dd_object) {
                   ret = SET_ERROR(EINVAL);
                   goto error;
           }
   
           /* initialize the wkey's ddobj */
           wkey->wk_ddobj = dd->dd_object;
   
           /* verify that the wkey is correct by opening its dsl key */
           ret = dsl_crypto_key_open(dp->dp_meta_objset, wkey,
               dd->dd_crypto_obj, FTAG, &dck);
           if (ret != 0)
                   goto error;
   
           /* initialize the wkey encryption parameters from the DSL Crypto Key */
           ret = zap_lookup(dp->dp_meta_objset, dd->dd_crypto_obj,
               zfs_prop_to_name(ZFS_PROP_KEYFORMAT), 8, 1, &keyformat);
           if (ret != 0)
                   goto error;
   
           ret = zap_lookup(dp->dp_meta_objset, dd->dd_crypto_obj,
               zfs_prop_to_name(ZFS_PROP_PBKDF2_SALT), 8, 1, &salt);
           if (ret != 0)
                   goto error;
   
           ret = zap_lookup(dp->dp_meta_objset, dd->dd_crypto_obj,
               zfs_prop_to_name(ZFS_PROP_PBKDF2_ITERS), 8, 1, &iters);
           if (ret != 0)
                   goto error;
   
           ASSERT3U(keyformat, <, ZFS_KEYFORMAT_FORMATS);
           ASSERT3U(keyformat, !=, ZFS_KEYFORMAT_NONE);
           IMPLY(keyformat == ZFS_KEYFORMAT_PASSPHRASE, iters != 0);
           IMPLY(keyformat == ZFS_KEYFORMAT_PASSPHRASE, salt != 0);
           IMPLY(keyformat != ZFS_KEYFORMAT_PASSPHRASE, iters == 0);
           IMPLY(keyformat != ZFS_KEYFORMAT_PASSPHRASE, salt == 0);
   
           wkey->wk_keyformat = keyformat;
           wkey->wk_salt = salt;
           wkey->wk_iters = iters;
   
           /*
            * At this point we have verified the wkey and confirmed that it can
            * be used to decrypt a DSL Crypto Key. We can simply cleanup and
            * return if this is all the user wanted to do.
            */
           if (noop)
                   goto error;
   
           /* insert the wrapping key into the keystore */
           ret = spa_keystore_load_wkey_impl(dp->dp_spa, wkey);
           if (ret != 0)
                   goto error;
   
           dsl_crypto_key_rele(dck, FTAG);
           dsl_dir_rele(dd, FTAG);
           dsl_pool_rele(dp, FTAG);
   
           /* create any zvols under this ds */
           zvol_create_minors_recursive(dsname);
   
           return (0);
   
   error:
           if (dck != NULL)
                   dsl_crypto_key_rele(dck, FTAG);
           if (dd != NULL)
                   dsl_dir_rele(dd, FTAG);
           if (dp != NULL)
                   dsl_pool_rele(dp, FTAG);
   
           return (ret);
   }
   
   int
   spa_keystore_unload_wkey_impl(spa_t *spa, uint64_t ddobj)
   {
           int ret;
           dsl_wrapping_key_t search_wkey;
           dsl_wrapping_key_t *found_wkey;
   
           /* init the search wrapping key */
           search_wkey.wk_ddobj = ddobj;
   
           rw_enter(&spa->spa_keystore.sk_wkeys_lock, RW_WRITER);
   
           /* remove the wrapping key from the keystore */
           found_wkey = avl_find(&spa->spa_keystore.sk_wkeys,
               &search_wkey, NULL);
           if (!found_wkey) {
                   ret = SET_ERROR(EACCES);
                   goto error_unlock;
           } else if (zfs_refcount_count(&found_wkey->wk_refcnt) != 0) {
                   ret = SET_ERROR(EBUSY);
                   goto error_unlock;
           }
           avl_remove(&spa->spa_keystore.sk_wkeys, found_wkey);
   
           rw_exit(&spa->spa_keystore.sk_wkeys_lock);
   
           /* free the wrapping key */
           dsl_wrapping_key_free(found_wkey);
   
           return (0);
   
   error_unlock:
           rw_exit(&spa->spa_keystore.sk_wkeys_lock);
           return (ret);
   }
   
   int
   spa_keystore_unload_wkey(const char *dsname)
   {
           int ret = 0;
           dsl_dir_t *dd = NULL;
           dsl_pool_t *dp = NULL;
           spa_t *spa = NULL;
   
           ret = spa_open(dsname, &spa, FTAG);
           if (ret != 0)
                   return (ret);
   
           /*
            * Wait for any outstanding txg IO to complete, releasing any
            * remaining references on the wkey.
            */
           if (spa_mode(spa) != SPA_MODE_READ)
                   txg_wait_synced(spa->spa_dsl_pool, 0);
   
           spa_close(spa, FTAG);
   
           /* hold the dsl dir */
           ret = dsl_pool_hold(dsname, FTAG, &dp);
           if (ret != 0)
                   goto error;
   
           if (!spa_feature_is_enabled(dp->dp_spa, SPA_FEATURE_ENCRYPTION)) {
                   ret = (SET_ERROR(ENOTSUP));
                   goto error;
           }
   
           ret = dsl_dir_hold(dp, dsname, FTAG, &dd, NULL);
           if (ret != 0) {
                   dd = NULL;
                   goto error;
           }
   
           /* unload the wkey */
           ret = spa_keystore_unload_wkey_impl(dp->dp_spa, dd->dd_object);
           if (ret != 0)
                   goto error;
   
           dsl_dir_rele(dd, FTAG);
           dsl_pool_rele(dp, FTAG);
   
           /* remove any zvols under this ds */
           zvol_remove_minors(dp->dp_spa, dsname, B_TRUE);
   
           return (0);
   
   error:
           if (dd != NULL)
                   dsl_dir_rele(dd, FTAG);
           if (dp != NULL)
                   dsl_pool_rele(dp, FTAG);
   
           return (ret);
   }
   
   void
   key_mapping_add_ref(dsl_key_mapping_t *km, const void *tag)
   {
           ASSERT3U(zfs_refcount_count(&km->km_refcnt), >=, 1);
           zfs_refcount_add(&km->km_refcnt, tag);
   }
   
   /*
    * The locking here is a little tricky to ensure we don't cause unnecessary
    * performance problems. We want to release a key mapping whenever someone
    * decrements the refcount to 0, but freeing the mapping requires removing
    * it from the spa_keystore, which requires holding sk_km_lock as a writer.
    * Most of the time we don't want to hold this lock as a writer, since the
    * same lock is held as a reader for each IO that needs to encrypt / decrypt
    * data for any dataset and in practice we will only actually free the
    * mapping after unmounting a dataset.
    */
   void
   key_mapping_rele(spa_t *spa, dsl_key_mapping_t *km, const void *tag)
   {
           ASSERT3U(zfs_refcount_count(&km->km_refcnt), >=, 1);
   
           if (zfs_refcount_remove(&km->km_refcnt, tag) != 0)
                   return;
   
           /*
            * We think we are going to need to free the mapping. Add a
            * reference to prevent most other releasers from thinking
            * this might be their responsibility. This is inherently
            * racy, so we will confirm that we are legitimately the
            * last holder once we have the sk_km_lock as a writer.
            */
           zfs_refcount_add(&km->km_refcnt, FTAG);
   
           rw_enter(&spa->spa_keystore.sk_km_lock, RW_WRITER);
           if (zfs_refcount_remove(&km->km_refcnt, FTAG) != 0) {
                   rw_exit(&spa->spa_keystore.sk_km_lock);
                   return;
           }
   
           avl_remove(&spa->spa_keystore.sk_key_mappings, km);
           rw_exit(&spa->spa_keystore.sk_km_lock);
   
           spa_keystore_dsl_key_rele(spa, km->km_key, km);
           zfs_refcount_destroy(&km->km_refcnt);
           kmem_free(km, sizeof (dsl_key_mapping_t));
   }
   
   int
   spa_keystore_create_mapping(spa_t *spa, dsl_dataset_t *ds, const void *tag,
       dsl_key_mapping_t **km_out)
   {
           int ret;
           avl_index_t where;
           dsl_key_mapping_t *km, *found_km;
           boolean_t should_free = B_FALSE;
   
           /* Allocate and initialize the mapping */
           km = kmem_zalloc(sizeof (dsl_key_mapping_t), KM_SLEEP);
           zfs_refcount_create(&km->km_refcnt);
   
           ret = spa_keystore_dsl_key_hold_dd(spa, ds->ds_dir, km, &km->km_key);
          if (ret != 0) {
                  zfs_refcount_destroy(&km->km_refcnt);
                  kmem_free(km, sizeof (dsl_key_mapping_t));
  
                  if (km_out != NULL)
                          *km_out = NULL;
                  return (ret);
          }
  
          km->km_dsobj = ds->ds_object;
  
          rw_enter(&spa->spa_keystore.sk_km_lock, RW_WRITER);
  
          /*
           * If a mapping already exists, simply increment its refcount and
           * cleanup the one we made. We want to allocate / free outside of
           * the lock because this lock is also used by the zio layer to lookup
           * key mappings. Otherwise, use the one we created. Normally, there will
           * only be one active reference at a time (the objset owner), but there
           * are times when there could be multiple async users.
           */
          found_km = avl_find(&spa->spa_keystore.sk_key_mappings, km, &where);
          if (found_km != NULL) {
                  should_free = B_TRUE;
                  zfs_refcount_add(&found_km->km_refcnt, tag);
                  if (km_out != NULL)
                          *km_out = found_km;
          } else {
                  zfs_refcount_add(&km->km_refcnt, tag);
                  avl_insert(&spa->spa_keystore.sk_key_mappings, km, where);
                  if (km_out != NULL)
                          *km_out = km;
          }
  
          rw_exit(&spa->spa_keystore.sk_km_lock);
  
          if (should_free) {
                  spa_keystore_dsl_key_rele(spa, km->km_key, km);
                  zfs_refcount_destroy(&km->km_refcnt);
                  kmem_free(km, sizeof (dsl_key_mapping_t));
          }
  
          return (0);
  }
  
  int
  spa_keystore_remove_mapping(spa_t *spa, uint64_t dsobj, const void *tag)
  {
          int ret;
          dsl_key_mapping_t search_km;
          dsl_key_mapping_t *found_km;
  
          /* init the search key mapping */
          search_km.km_dsobj = dsobj;
  
          rw_enter(&spa->spa_keystore.sk_km_lock, RW_READER);
  
          /* find the matching mapping */
          found_km = avl_find(&spa->spa_keystore.sk_key_mappings,
              &search_km, NULL);
          if (found_km == NULL) {
                  ret = SET_ERROR(ENOENT);
                  goto error_unlock;
          }
  
          rw_exit(&spa->spa_keystore.sk_km_lock);
  
          key_mapping_rele(spa, found_km, tag);
  
          return (0);
  
  error_unlock:
          rw_exit(&spa->spa_keystore.sk_km_lock);
          return (ret);
  }
  
  /*
   * This function is primarily used by the zio and arc layer to lookup
   * DSL Crypto Keys for encryption. Callers must release the key with
   * spa_keystore_dsl_key_rele(). The function may also be called with
   * dck_out == NULL and tag == NULL to simply check that a key exists
   * without getting a reference to it.
   */
  int
  spa_keystore_lookup_key(spa_t *spa, uint64_t dsobj, const void *tag,
      dsl_crypto_key_t **dck_out)
  {
          int ret;
          dsl_key_mapping_t search_km;
          dsl_key_mapping_t *found_km;
  
          ASSERT((tag != NULL && dck_out != NULL) ||
              (tag == NULL && dck_out == NULL));
  
          /* init the search key mapping */
          search_km.km_dsobj = dsobj;
  
          rw_enter(&spa->spa_keystore.sk_km_lock, RW_READER);
  
          /* remove the mapping from the tree */
          found_km = avl_find(&spa->spa_keystore.sk_key_mappings, &search_km,
              NULL);
          if (found_km == NULL) {
                  ret = SET_ERROR(ENOENT);
                  goto error_unlock;
          }
  
          if (found_km && tag)
                  zfs_refcount_add(&found_km->km_key->dck_holds, tag);
  
          rw_exit(&spa->spa_keystore.sk_km_lock);
  
          if (dck_out != NULL)
                  *dck_out = found_km->km_key;
          return (0);
  
  error_unlock:
          rw_exit(&spa->spa_keystore.sk_km_lock);
  
          if (dck_out != NULL)
                  *dck_out = NULL;
          return (ret);
  }
  
  static int
  dmu_objset_check_wkey_loaded(dsl_dir_t *dd)
  {
          int ret;
          dsl_wrapping_key_t *wkey = NULL;
  
          ret = spa_keystore_wkey_hold_dd(dd->dd_pool->dp_spa, dd, FTAG,
              &wkey);
          if (ret != 0)
                  return (SET_ERROR(EACCES));
  
          dsl_wrapping_key_rele(wkey, FTAG);
  
          return (0);
  }
  
  zfs_keystatus_t
  dsl_dataset_get_keystatus(dsl_dir_t *dd)
  {
          /* check if this dd has a has a dsl key */
          if (dd->dd_crypto_obj == 0)
                  return (ZFS_KEYSTATUS_NONE);
  
          return (dmu_objset_check_wkey_loaded(dd) == 0 ?
              ZFS_KEYSTATUS_AVAILABLE : ZFS_KEYSTATUS_UNAVAILABLE);
  }
  
  static int
  dsl_dir_get_crypt(dsl_dir_t *dd, uint64_t *crypt)
  {
          if (dd->dd_crypto_obj == 0) {
                  *crypt = ZIO_CRYPT_OFF;
                  return (0);
          }
  
          return (zap_lookup(dd->dd_pool->dp_meta_objset, dd->dd_crypto_obj,
              DSL_CRYPTO_KEY_CRYPTO_SUITE, 8, 1, crypt));
  }
  
  static void
  dsl_crypto_key_sync_impl(objset_t *mos, uint64_t dckobj, uint64_t crypt,
      uint64_t root_ddobj, uint64_t guid, uint8_t *iv, uint8_t *mac,
      uint8_t *keydata, uint8_t *hmac_keydata, uint64_t keyformat,
      uint64_t salt, uint64_t iters, dmu_tx_t *tx)
  {
          VERIFY0(zap_update(mos, dckobj, DSL_CRYPTO_KEY_CRYPTO_SUITE, 8, 1,
              &crypt, tx));
          VERIFY0(zap_update(mos, dckobj, DSL_CRYPTO_KEY_ROOT_DDOBJ, 8, 1,
              &root_ddobj, tx));
          VERIFY0(zap_update(mos, dckobj, DSL_CRYPTO_KEY_GUID, 8, 1,
              &guid, tx));
          VERIFY0(zap_update(mos, dckobj, DSL_CRYPTO_KEY_IV, 1, WRAPPING_IV_LEN,
              iv, tx));
          VERIFY0(zap_update(mos, dckobj, DSL_CRYPTO_KEY_MAC, 1, WRAPPING_MAC_LEN,
              mac, tx));
          VERIFY0(zap_update(mos, dckobj, DSL_CRYPTO_KEY_MASTER_KEY, 1,
              MASTER_KEY_MAX_LEN, keydata, tx));
          VERIFY0(zap_update(mos, dckobj, DSL_CRYPTO_KEY_HMAC_KEY, 1,
              SHA512_HMAC_KEYLEN, hmac_keydata, tx));
          VERIFY0(zap_update(mos, dckobj, zfs_prop_to_name(ZFS_PROP_KEYFORMAT),
              8, 1, &keyformat, tx));
          VERIFY0(zap_update(mos, dckobj, zfs_prop_to_name(ZFS_PROP_PBKDF2_SALT),
              8, 1, &salt, tx));
          VERIFY0(zap_update(mos, dckobj, zfs_prop_to_name(ZFS_PROP_PBKDF2_ITERS),
              8, 1, &iters, tx));
  }
  
  static void
  dsl_crypto_key_sync(dsl_crypto_key_t *dck, dmu_tx_t *tx)
  {
          zio_crypt_key_t *key = &dck->dck_key;
          dsl_wrapping_key_t *wkey = dck->dck_wkey;
          uint8_t keydata[MASTER_KEY_MAX_LEN];
          uint8_t hmac_keydata[SHA512_HMAC_KEYLEN];
          uint8_t iv[WRAPPING_IV_LEN];
          uint8_t mac[WRAPPING_MAC_LEN];
  
          ASSERT(dmu_tx_is_syncing(tx));
          ASSERT3U(key->zk_crypt, <, ZIO_CRYPT_FUNCTIONS);
  
          /* encrypt and store the keys along with the IV and MAC */
          VERIFY0(zio_crypt_key_wrap(&dck->dck_wkey->wk_key, key, iv, mac,
              keydata, hmac_keydata));
  
          /* update the ZAP with the obtained values */
          dsl_crypto_key_sync_impl(tx->tx_pool->dp_meta_objset, dck->dck_obj,
              key->zk_crypt, wkey->wk_ddobj, key->zk_guid, iv, mac, keydata,
              hmac_keydata, wkey->wk_keyformat, wkey->wk_salt, wkey->wk_iters,
              tx);
  }
  
  typedef struct spa_keystore_change_key_args {
          const char *skcka_dsname;
          dsl_crypto_params_t *skcka_cp;
  } spa_keystore_change_key_args_t;
  
  static int
  spa_keystore_change_key_check(void *arg, dmu_tx_t *tx)
  {
          int ret;
          dsl_dir_t *dd = NULL;
          dsl_pool_t *dp = dmu_tx_pool(tx);
          spa_keystore_change_key_args_t *skcka = arg;
          dsl_crypto_params_t *dcp = skcka->skcka_cp;
          uint64_t rddobj;
  
          /* check for the encryption feature */
          if (!spa_feature_is_enabled(dp->dp_spa, SPA_FEATURE_ENCRYPTION)) {
                  ret = SET_ERROR(ENOTSUP);
                  goto error;
          }
  
          /* check for valid key change command */
          if (dcp->cp_cmd != DCP_CMD_NEW_KEY &&
              dcp->cp_cmd != DCP_CMD_INHERIT &&
              dcp->cp_cmd != DCP_CMD_FORCE_NEW_KEY &&
              dcp->cp_cmd != DCP_CMD_FORCE_INHERIT) {
                  ret = SET_ERROR(EINVAL);
                  goto error;
          }
  
          /* hold the dd */
          ret = dsl_dir_hold(dp, skcka->skcka_dsname, FTAG, &dd, NULL);
          if (ret != 0) {
                  dd = NULL;
                  goto error;
          }
  
          /* verify that the dataset is encrypted */
          if (dd->dd_crypto_obj == 0) {
                  ret = SET_ERROR(EINVAL);
                  goto error;
          }
  
          /* clones must always use their origin's key */
          if (dsl_dir_is_clone(dd)) {
                  ret = SET_ERROR(EINVAL);
                  goto error;
          }
  
          /* lookup the ddobj we are inheriting the keylocation from */
          ret = dsl_dir_get_encryption_root_ddobj(dd, &rddobj);
          if (ret != 0)
                  goto error;
  
          /* Handle inheritance */
          if (dcp->cp_cmd == DCP_CMD_INHERIT ||
              dcp->cp_cmd == DCP_CMD_FORCE_INHERIT) {
                  /* no other encryption params should be given */
                  if (dcp->cp_crypt != ZIO_CRYPT_INHERIT ||
                      dcp->cp_keylocation != NULL ||
                      dcp->cp_wkey != NULL) {
                          ret = SET_ERROR(EINVAL);
                          goto error;
                  }
  
                  /* check that this is an encryption root */
                  if (dd->dd_object != rddobj) {
                          ret = SET_ERROR(EINVAL);
                          goto error;
                  }
  
                  /* check that the parent is encrypted */
                  if (dd->dd_parent->dd_crypto_obj == 0) {
                          ret = SET_ERROR(EINVAL);
                          goto error;
                  }
  
                  /* if we are rewrapping check that both keys are loaded */
                  if (dcp->cp_cmd == DCP_CMD_INHERIT) {
                          ret = dmu_objset_check_wkey_loaded(dd);
                          if (ret != 0)
                                  goto error;
  
                          ret = dmu_objset_check_wkey_loaded(dd->dd_parent);
                          if (ret != 0)
                                  goto error;
                  }
  
                  dsl_dir_rele(dd, FTAG);
                  return (0);
          }
  
          /* handle forcing an encryption root without rewrapping */
          if (dcp->cp_cmd == DCP_CMD_FORCE_NEW_KEY) {
                  /* no other encryption params should be given */
                  if (dcp->cp_crypt != ZIO_CRYPT_INHERIT ||
                      dcp->cp_keylocation != NULL ||
                      dcp->cp_wkey != NULL) {
                          ret = SET_ERROR(EINVAL);
                          goto error;
                  }
  
                  /* check that this is not an encryption root */
                  if (dd->dd_object == rddobj) {
                          ret = SET_ERROR(EINVAL);
                          goto error;
                  }
  
                  dsl_dir_rele(dd, FTAG);
                  return (0);
          }
  
          /* crypt cannot be changed after creation */
          if (dcp->cp_crypt != ZIO_CRYPT_INHERIT) {
                  ret = SET_ERROR(EINVAL);
                  goto error;
          }
  
          /* we are not inheritting our parent's wkey so we need one ourselves */
          if (dcp->cp_wkey == NULL) {
                  ret = SET_ERROR(EINVAL);
                  goto error;
          }
  
          /* check for a valid keyformat for the new wrapping key */
          if (dcp->cp_wkey->wk_keyformat >= ZFS_KEYFORMAT_FORMATS ||
              dcp->cp_wkey->wk_keyformat == ZFS_KEYFORMAT_NONE) {
                  ret = SET_ERROR(EINVAL);
                  goto error;
          }
  
          /*
           * If this dataset is not currently an encryption root we need a new
           * keylocation for this dataset's new wrapping key. Otherwise we can
           * just keep the one we already had.
           */
          if (dd->dd_object != rddobj && dcp->cp_keylocation == NULL) {
                  ret = SET_ERROR(EINVAL);
                  goto error;
          }
  
          /* check that the keylocation is valid if it is not NULL */
          if (dcp->cp_keylocation != NULL &&
              !zfs_prop_valid_keylocation(dcp->cp_keylocation, B_TRUE)) {
                  ret = SET_ERROR(EINVAL);
                  goto error;
          }
  
          /* passphrases require pbkdf2 salt and iters */
          if (dcp->cp_wkey->wk_keyformat == ZFS_KEYFORMAT_PASSPHRASE) {
                  if (dcp->cp_wkey->wk_salt == 0 ||
                      dcp->cp_wkey->wk_iters < MIN_PBKDF2_ITERATIONS) {
                          ret = SET_ERROR(EINVAL);
                          goto error;
                  }
          } else {
                  if (dcp->cp_wkey->wk_salt != 0 || dcp->cp_wkey->wk_iters != 0) {
                          ret = SET_ERROR(EINVAL);
                          goto error;
                  }
          }
  
          /* make sure the dd's wkey is loaded */
          ret = dmu_objset_check_wkey_loaded(dd);
          if (ret != 0)
                  goto error;
  
          dsl_dir_rele(dd, FTAG);
  
          return (0);
  
  error:
          if (dd != NULL)
                  dsl_dir_rele(dd, FTAG);
  
          return (ret);
  }
  
  /*
   * This function deals with the intricacies of updating wrapping
   * key references and encryption roots recursively in the event
   * of a call to 'zfs change-key' or 'zfs promote'. The 'skip'
   * parameter should always be set to B_FALSE when called
   * externally.
   */
  static void
  spa_keystore_change_key_sync_impl(uint64_t rddobj, uint64_t ddobj,
      uint64_t new_rddobj, dsl_wrapping_key_t *wkey, boolean_t skip,
      dmu_tx_t *tx)
  {
          int ret;
          zap_cursor_t *zc;
          zap_attribute_t *za;
          dsl_pool_t *dp = dmu_tx_pool(tx);
          dsl_dir_t *dd = NULL;
          dsl_crypto_key_t *dck = NULL;
          uint64_t curr_rddobj;
  
          ASSERT(RW_WRITE_HELD(&dp->dp_spa->spa_keystore.sk_wkeys_lock));
  
          /* hold the dd */
          VERIFY0(dsl_dir_hold_obj(dp, ddobj, NULL, FTAG, &dd));
  
          /* ignore special dsl dirs */
          if (dd->dd_myname[0] == '$' || dd->dd_myname[0] == '%') {
                  dsl_dir_rele(dd, FTAG);
                  return;
          }
  
          ret = dsl_dir_get_encryption_root_ddobj(dd, &curr_rddobj);
          VERIFY(ret == 0 || ret == ENOENT);
  
          /*
           * Stop recursing if this dsl dir didn't inherit from the root
           * or if this dd is a clone.
           */
          if (ret == ENOENT ||
              (!skip && (curr_rddobj != rddobj || dsl_dir_is_clone(dd)))) {
                  dsl_dir_rele(dd, FTAG);
                  return;
          }
  
          /*
           * If we don't have a wrapping key just update the dck to reflect the
           * new encryption root. Otherwise rewrap the entire dck and re-sync it
           * to disk. If skip is set, we don't do any of this work.
           */
          if (!skip) {
                  if (wkey == NULL) {
                          VERIFY0(zap_update(dp->dp_meta_objset,
                              dd->dd_crypto_obj,
                              DSL_CRYPTO_KEY_ROOT_DDOBJ, 8, 1,
                              &new_rddobj, tx));
                  } else {
                          VERIFY0(spa_keystore_dsl_key_hold_dd(dp->dp_spa, dd,
                              FTAG, &dck));
                          dsl_wrapping_key_hold(wkey, dck);
                          dsl_wrapping_key_rele(dck->dck_wkey, dck);
                          dck->dck_wkey = wkey;
                          dsl_crypto_key_sync(dck, tx);
                          spa_keystore_dsl_key_rele(dp->dp_spa, dck, FTAG);
                  }
          }
  
          zc = kmem_alloc(sizeof (zap_cursor_t), KM_SLEEP);
          za = kmem_alloc(sizeof (zap_attribute_t), KM_SLEEP);
  
          /* Recurse into all child dsl dirs. */
          for (zap_cursor_init(zc, dp->dp_meta_objset,
              dsl_dir_phys(dd)->dd_child_dir_zapobj);
              zap_cursor_retrieve(zc, za) == 0;
              zap_cursor_advance(zc)) {
                  spa_keystore_change_key_sync_impl(rddobj,
                      za->za_first_integer, new_rddobj, wkey, B_FALSE, tx);
          }
          zap_cursor_fini(zc);
  
          /*
           * Recurse into all dsl dirs of clones. We utilize the skip parameter
           * here so that we don't attempt to process the clones directly. This
           * is because the clone and its origin share the same dck, which has
           * already been updated.
           */
          for (zap_cursor_init(zc, dp->dp_meta_objset,
              dsl_dir_phys(dd)->dd_clones);
              zap_cursor_retrieve(zc, za) == 0;
              zap_cursor_advance(zc)) {
                  dsl_dataset_t *clone;
  
                  VERIFY0(dsl_dataset_hold_obj(dp, za->za_first_integer,
                      FTAG, &clone));
                  spa_keystore_change_key_sync_impl(rddobj,
                      clone->ds_dir->dd_object, new_rddobj, wkey, B_TRUE, tx);
                  dsl_dataset_rele(clone, FTAG);
          }
          zap_cursor_fini(zc);
  
          kmem_free(za, sizeof (zap_attribute_t));
          kmem_free(zc, sizeof (zap_cursor_t));
  
          dsl_dir_rele(dd, FTAG);
  }
  
  static void
  spa_keystore_change_key_sync(void *arg, dmu_tx_t *tx)
  {
          dsl_dataset_t *ds;
          avl_index_t where;
          dsl_pool_t *dp = dmu_tx_pool(tx);
          spa_t *spa = dp->dp_spa;
          spa_keystore_change_key_args_t *skcka = arg;
          dsl_crypto_params_t *dcp = skcka->skcka_cp;
          dsl_wrapping_key_t *wkey = NULL, *found_wkey;
          dsl_wrapping_key_t wkey_search;
          const char *keylocation = dcp->cp_keylocation;
          uint64_t rddobj, new_rddobj;
  
          /* create and initialize the wrapping key */
          VERIFY0(dsl_dataset_hold(dp, skcka->skcka_dsname, FTAG, &ds));
          ASSERT(!ds->ds_is_snapshot);
  
          if (dcp->cp_cmd == DCP_CMD_NEW_KEY ||
              dcp->cp_cmd == DCP_CMD_FORCE_NEW_KEY) {
                  /*
                   * We are changing to a new wkey. Set additional properties
                   * which can be sent along with this ioctl. Note that this
                   * command can set keylocation even if it can't normally be
                   * set via 'zfs set' due to a non-local keylocation.
                   */
                  if (dcp->cp_cmd == DCP_CMD_NEW_KEY) {
                          wkey = dcp->cp_wkey;
                          wkey->wk_ddobj = ds->ds_dir->dd_object;
                  } else {
                          keylocation = "prompt";
                  }
  
                  if (keylocation != NULL) {
                          dsl_prop_set_sync_impl(ds,
                              zfs_prop_to_name(ZFS_PROP_KEYLOCATION),
                              ZPROP_SRC_LOCAL, 1, strlen(keylocation) + 1,
                              keylocation, tx);
                  }
  
                  VERIFY0(dsl_dir_get_encryption_root_ddobj(ds->ds_dir, &rddobj));
                  new_rddobj = ds->ds_dir->dd_object;
          } else {
                  /*
                   * We are inheritting the parent's wkey. Unset any local
                   * keylocation and grab a reference to the wkey.
                   */
                  if (dcp->cp_cmd == DCP_CMD_INHERIT) {
                          VERIFY0(spa_keystore_wkey_hold_dd(spa,
                              ds->ds_dir->dd_parent, FTAG, &wkey));
                  }
  
                  dsl_prop_set_sync_impl(ds,
                      zfs_prop_to_name(ZFS_PROP_KEYLOCATION), ZPROP_SRC_NONE,
                      0, 0, NULL, tx);
  
                  rddobj = ds->ds_dir->dd_object;
                  VERIFY0(dsl_dir_get_encryption_root_ddobj(ds->ds_dir->dd_parent,
                      &new_rddobj));
          }
  
          if (wkey == NULL) {
                  ASSERT(dcp->cp_cmd == DCP_CMD_FORCE_INHERIT ||
                      dcp->cp_cmd == DCP_CMD_FORCE_NEW_KEY);
          }
  
          rw_enter(&spa->spa_keystore.sk_wkeys_lock, RW_WRITER);
  
          /* recurse through all children and rewrap their keys */
          spa_keystore_change_key_sync_impl(rddobj, ds->ds_dir->dd_object,
              new_rddobj, wkey, B_FALSE, tx);
  
          /*
           * All references to the old wkey should be released now (if it
           * existed). Replace the wrapping key.
           */
          wkey_search.wk_ddobj = ds->ds_dir->dd_object;
          found_wkey = avl_find(&spa->spa_keystore.sk_wkeys, &wkey_search, NULL);
          if (found_wkey != NULL) {
                  ASSERT0(zfs_refcount_count(&found_wkey->wk_refcnt));
                  avl_remove(&spa->spa_keystore.sk_wkeys, found_wkey);
                  dsl_wrapping_key_free(found_wkey);
          }
  
          if (dcp->cp_cmd == DCP_CMD_NEW_KEY) {
                  avl_find(&spa->spa_keystore.sk_wkeys, wkey, &where);
                  avl_insert(&spa->spa_keystore.sk_wkeys, wkey, where);
          } else if (wkey != NULL) {
                  dsl_wrapping_key_rele(wkey, FTAG);
          }
  
          rw_exit(&spa->spa_keystore.sk_wkeys_lock);
  
          dsl_dataset_rele(ds, FTAG);
  }
  
  int
  spa_keystore_change_key(const char *dsname, dsl_crypto_params_t *dcp)
  {
          spa_keystore_change_key_args_t skcka;
  
          /* initialize the args struct */
          skcka.skcka_dsname = dsname;
          skcka.skcka_cp = dcp;
  
          /*
           * Perform the actual work in syncing context. The blocks modified
           * here could be calculated but it would require holding the pool
           * lock and traversing all of the datasets that will have their keys
           * changed.
           */
          return (dsl_sync_task(dsname, spa_keystore_change_key_check,
              spa_keystore_change_key_sync, &skcka, 15,
              ZFS_SPACE_CHECK_RESERVED));
  }
  
  int
  dsl_dir_rename_crypt_check(dsl_dir_t *dd, dsl_dir_t *newparent)
  {
          int ret;
          uint64_t curr_rddobj, parent_rddobj;
  
          if (dd->dd_crypto_obj == 0)
                  return (0);
  
          ret = dsl_dir_get_encryption_root_ddobj(dd, &curr_rddobj);
          if (ret != 0)
                  goto error;
  
          /*
           * if this is not an encryption root, we must make sure we are not
           * moving dd to a new encryption root
           */
          if (dd->dd_object != curr_rddobj) {
                  ret = dsl_dir_get_encryption_root_ddobj(newparent,
                      &parent_rddobj);
                  if (ret != 0)
                          goto error;
  
                  if (parent_rddobj != curr_rddobj) {
                          ret = SET_ERROR(EACCES);
                          goto error;
                  }
          }
  
          return (0);
  
  error:
          return (ret);
  }
  
  /*
   * Check to make sure that a promote from targetdd to origindd will not require
   * any key rewraps.
   */
  int
  dsl_dataset_promote_crypt_check(dsl_dir_t *target, dsl_dir_t *origin)
  {
          int ret;
          uint64_t rddobj, op_rddobj, tp_rddobj;
  
          /* If the dataset is not encrypted we don't need to check anything */
          if (origin->dd_crypto_obj == 0)
                  return (0);
  
          /*
           * If we are not changing the first origin snapshot in a chain
           * the encryption root won't change either.
           */
          if (dsl_dir_is_clone(origin))
                  return (0);
  
          /*
           * If the origin is the encryption root we will update
           * the DSL Crypto Key to point to the target instead.
           */
          ret = dsl_dir_get_encryption_root_ddobj(origin, &rddobj);
          if (ret != 0)
                  return (ret);
  
          if (rddobj == origin->dd_object)
                  return (0);
  
          /*
           * The origin is inheriting its encryption root from its parent.
           * Check that the parent of the target has the same encryption root.
           */
          ret = dsl_dir_get_encryption_root_ddobj(origin->dd_parent, &op_rddobj);
          if (ret == ENOENT)
                  return (SET_ERROR(EACCES));
          else if (ret != 0)
                  return (ret);
  
          ret = dsl_dir_get_encryption_root_ddobj(target->dd_parent, &tp_rddobj);
          if (ret == ENOENT)
                  return (SET_ERROR(EACCES));
          else if (ret != 0)
                  return (ret);
  
          if (op_rddobj != tp_rddobj)
                  return (SET_ERROR(EACCES));
  
          return (0);
  }
  
  void
  dsl_dataset_promote_crypt_sync(dsl_dir_t *target, dsl_dir_t *origin,
      dmu_tx_t *tx)
  {
          uint64_t rddobj;
          dsl_pool_t *dp = target->dd_pool;
          dsl_dataset_t *targetds;
          dsl_dataset_t *originds;
          char *keylocation;
  
          if (origin->dd_crypto_obj == 0)
                  return;
          if (dsl_dir_is_clone(origin))
                  return;
  
          VERIFY0(dsl_dir_get_encryption_root_ddobj(origin, &rddobj));
  
          if (rddobj != origin->dd_object)
                  return;
  
          /*
           * If the target is being promoted to the encryption root update the
           * DSL Crypto Key and keylocation to reflect that. We also need to
           * update the DSL Crypto Keys of all children inheritting their
           * encryption root to point to the new target. Otherwise, the check
           * function ensured that the encryption root will not change.
           */
          keylocation = kmem_alloc(ZAP_MAXVALUELEN, KM_SLEEP);
  
          VERIFY0(dsl_dataset_hold_obj(dp,
              dsl_dir_phys(target)->dd_head_dataset_obj, FTAG, &targetds));
          VERIFY0(dsl_dataset_hold_obj(dp,
              dsl_dir_phys(origin)->dd_head_dataset_obj, FTAG, &originds));
  
          VERIFY0(dsl_prop_get_dd(origin, zfs_prop_to_name(ZFS_PROP_KEYLOCATION),
              1, ZAP_MAXVALUELEN, keylocation, NULL, B_FALSE));
          dsl_prop_set_sync_impl(targetds, zfs_prop_to_name(ZFS_PROP_KEYLOCATION),
              ZPROP_SRC_LOCAL, 1, strlen(keylocation) + 1, keylocation, tx);
          dsl_prop_set_sync_impl(originds, zfs_prop_to_name(ZFS_PROP_KEYLOCATION),
              ZPROP_SRC_NONE, 0, 0, NULL, tx);
  
          rw_enter(&dp->dp_spa->spa_keystore.sk_wkeys_lock, RW_WRITER);
          spa_keystore_change_key_sync_impl(rddobj, origin->dd_object,
              target->dd_object, NULL, B_FALSE, tx);
          rw_exit(&dp->dp_spa->spa_keystore.sk_wkeys_lock);
  
          dsl_dataset_rele(targetds, FTAG);
          dsl_dataset_rele(originds, FTAG);
          kmem_free(keylocation, ZAP_MAXVALUELEN);
  }
  
  int
  dmu_objset_create_crypt_check(dsl_dir_t *parentdd, dsl_crypto_params_t *dcp,
      boolean_t *will_encrypt)
  {
          int ret;
          uint64_t pcrypt, crypt;
          dsl_crypto_params_t dummy_dcp = { 0 };
  
          if (will_encrypt != NULL)
                  *will_encrypt = B_FALSE;
  
          if (dcp == NULL)
                  dcp = &dummy_dcp;
  
          if (dcp->cp_cmd != DCP_CMD_NONE)
                  return (SET_ERROR(EINVAL));
  
          if (parentdd != NULL) {
                  ret = dsl_dir_get_crypt(parentdd, &pcrypt);
                  if (ret != 0)
                          return (ret);
          } else {
                  pcrypt = ZIO_CRYPT_OFF;
          }
  
          crypt = (dcp->cp_crypt == ZIO_CRYPT_INHERIT) ? pcrypt : dcp->cp_crypt;
  
          ASSERT3U(pcrypt, !=, ZIO_CRYPT_INHERIT);
          ASSERT3U(crypt, !=, ZIO_CRYPT_INHERIT);
  
          /* check for valid dcp with no encryption (inherited or local) */
          if (crypt == ZIO_CRYPT_OFF) {
                  /* Must not specify encryption params */
                  if (dcp->cp_wkey != NULL ||
                      (dcp->cp_keylocation != NULL &&
                      strcmp(dcp->cp_keylocation, "none") != 0))
                          return (SET_ERROR(EINVAL));
  
                  return (0);
          }
  
          if (will_encrypt != NULL)
                  *will_encrypt = B_TRUE;
  
          /*
           * We will now definitely be encrypting. Check the feature flag. When
           * creating the pool the caller will check this for us since we won't
           * technically have the feature activated yet.
           */
          if (parentdd != NULL &&
              !spa_feature_is_enabled(parentdd->dd_pool->dp_spa,
              SPA_FEATURE_ENCRYPTION)) {
                  return (SET_ERROR(EOPNOTSUPP));
          }
  
          /* Check for errata #4 (encryption enabled, bookmark_v2 disabled) */
          if (parentdd != NULL &&
              !spa_feature_is_enabled(parentdd->dd_pool->dp_spa,
              SPA_FEATURE_BOOKMARK_V2)) {
                  return (SET_ERROR(EOPNOTSUPP));
          }
  
          /* handle inheritance */
          if (dcp->cp_wkey == NULL) {
                  ASSERT3P(parentdd, !=, NULL);
  
                  /* key must be fully unspecified */
                  if (dcp->cp_keylocation != NULL)
                          return (SET_ERROR(EINVAL));
  
                  /* parent must have a key to inherit */
                  if (pcrypt == ZIO_CRYPT_OFF)
                          return (SET_ERROR(EINVAL));
  
                  /* check for parent key */
                  ret = dmu_objset_check_wkey_loaded(parentdd);
                  if (ret != 0)
                          return (ret);
  
                  return (0);
          }
  
          /* At this point we should have a fully specified key. Check location */
          if (dcp->cp_keylocation == NULL ||
              !zfs_prop_valid_keylocation(dcp->cp_keylocation, B_TRUE))
                  return (SET_ERROR(EINVAL));
  
          /* Must have fully specified keyformat */
          switch (dcp->cp_wkey->wk_keyformat) {
          case ZFS_KEYFORMAT_HEX:
          case ZFS_KEYFORMAT_RAW:
                  /* requires no pbkdf2 iters and salt */
                  if (dcp->cp_wkey->wk_salt != 0 || dcp->cp_wkey->wk_iters != 0)
                          return (SET_ERROR(EINVAL));
                  break;
          case ZFS_KEYFORMAT_PASSPHRASE:
                  /* requires pbkdf2 iters and salt */
                  if (dcp->cp_wkey->wk_salt == 0 ||
                      dcp->cp_wkey->wk_iters < MIN_PBKDF2_ITERATIONS)
                          return (SET_ERROR(EINVAL));
                  break;
          case ZFS_KEYFORMAT_NONE:
          default:
                  /* keyformat must be specified and valid */
                  return (SET_ERROR(EINVAL));
          }
  
          return (0);
  }
  
  void
  dsl_dataset_create_crypt_sync(uint64_t dsobj, dsl_dir_t *dd,
      dsl_dataset_t *origin, dsl_crypto_params_t *dcp, dmu_tx_t *tx)
  {
          dsl_pool_t *dp = dd->dd_pool;
          uint64_t crypt;
          dsl_wrapping_key_t *wkey;
  
          /* clones always use their origin's wrapping key */
          if (dsl_dir_is_clone(dd)) {
                  ASSERT3P(dcp, ==, NULL);
  
                  /*
                   * If this is an encrypted clone we just need to clone the
                   * dck into dd. Zapify the dd so we can do that.
                   */
                  if (origin->ds_dir->dd_crypto_obj != 0) {
                          dmu_buf_will_dirty(dd->dd_dbuf, tx);
                          dsl_dir_zapify(dd, tx);
  
                          dd->dd_crypto_obj =
                              dsl_crypto_key_clone_sync(origin->ds_dir, tx);
                          VERIFY0(zap_add(dp->dp_meta_objset, dd->dd_object,
                              DD_FIELD_CRYPTO_KEY_OBJ, sizeof (uint64_t), 1,
                              &dd->dd_crypto_obj, tx));
                  }
  
                  return;
          }
  
          /*
           * A NULL dcp at this point indicates this is the origin dataset
           * which does not have an objset to encrypt. Raw receives will handle
           * encryption separately later. In both cases we can simply return.
           */
          if (dcp == NULL || dcp->cp_cmd == DCP_CMD_RAW_RECV)
                  return;
  
          crypt = dcp->cp_crypt;
          wkey = dcp->cp_wkey;
  
          /* figure out the effective crypt */
          if (crypt == ZIO_CRYPT_INHERIT && dd->dd_parent != NULL)
                  VERIFY0(dsl_dir_get_crypt(dd->dd_parent, &crypt));
  
          /* if we aren't doing encryption just return */
          if (crypt == ZIO_CRYPT_OFF || crypt == ZIO_CRYPT_INHERIT)
                  return;
  
          /* zapify the dd so that we can add the crypto key obj to it */
          dmu_buf_will_dirty(dd->dd_dbuf, tx);
          dsl_dir_zapify(dd, tx);
  
          /* use the new key if given or inherit from the parent */
          if (wkey == NULL) {
                  VERIFY0(spa_keystore_wkey_hold_dd(dp->dp_spa,
                      dd->dd_parent, FTAG, &wkey));
          } else {
                  wkey->wk_ddobj = dd->dd_object;
          }
  
          ASSERT3P(wkey, !=, NULL);
  
          /* Create or clone the DSL crypto key and activate the feature */
          dd->dd_crypto_obj = dsl_crypto_key_create_sync(crypt, wkey, tx);
          VERIFY0(zap_add(dp->dp_meta_objset, dd->dd_object,
              DD_FIELD_CRYPTO_KEY_OBJ, sizeof (uint64_t), 1, &dd->dd_crypto_obj,
              tx));
          dsl_dataset_activate_feature(dsobj, SPA_FEATURE_ENCRYPTION,
              (void *)B_TRUE, tx);
  
          /*
           * If we inherited the wrapping key we release our reference now.
           * Otherwise, this is a new key and we need to load it into the
           * keystore.
           */
          if (dcp->cp_wkey == NULL) {
                  dsl_wrapping_key_rele(wkey, FTAG);
          } else {
                  VERIFY0(spa_keystore_load_wkey_impl(dp->dp_spa, wkey));
          }
  }
  
  typedef struct dsl_crypto_recv_key_arg {
          uint64_t dcrka_dsobj;
          uint64_t dcrka_fromobj;
          dmu_objset_type_t dcrka_ostype;
          nvlist_t *dcrka_nvl;
          boolean_t dcrka_do_key;
  } dsl_crypto_recv_key_arg_t;
  
  static int
  dsl_crypto_recv_raw_objset_check(dsl_dataset_t *ds, dsl_dataset_t *fromds,
      dmu_objset_type_t ostype, nvlist_t *nvl, dmu_tx_t *tx)
  {
          int ret;
          objset_t *os;
          dnode_t *mdn;
          uint8_t *buf = NULL;
          uint_t len;
          uint64_t intval, nlevels, blksz, ibs;
          uint64_t nblkptr, maxblkid;
  
          if (ostype != DMU_OST_ZFS && ostype != DMU_OST_ZVOL)
                  return (SET_ERROR(EINVAL));
  
          /* raw receives also need info about the structure of the metadnode */
          ret = nvlist_lookup_uint64(nvl, "mdn_compress", &intval);
          if (ret != 0 || intval >= ZIO_COMPRESS_LEGACY_FUNCTIONS)
                  return (SET_ERROR(EINVAL));
  
          ret = nvlist_lookup_uint64(nvl, "mdn_checksum", &intval);
          if (ret != 0 || intval >= ZIO_CHECKSUM_LEGACY_FUNCTIONS)
                  return (SET_ERROR(EINVAL));
  
          ret = nvlist_lookup_uint64(nvl, "mdn_nlevels", &nlevels);
          if (ret != 0 || nlevels > DN_MAX_LEVELS)
                  return (SET_ERROR(EINVAL));
  
          ret = nvlist_lookup_uint64(nvl, "mdn_blksz", &blksz);
          if (ret != 0 || blksz < SPA_MINBLOCKSIZE)
                  return (SET_ERROR(EINVAL));
          else if (blksz > spa_maxblocksize(tx->tx_pool->dp_spa))
                  return (SET_ERROR(ENOTSUP));
  
          ret = nvlist_lookup_uint64(nvl, "mdn_indblkshift", &ibs);
          if (ret != 0 || ibs < DN_MIN_INDBLKSHIFT || ibs > DN_MAX_INDBLKSHIFT)
                  return (SET_ERROR(ENOTSUP));
  
          ret = nvlist_lookup_uint64(nvl, "mdn_nblkptr", &nblkptr);
          if (ret != 0 || nblkptr != DN_MAX_NBLKPTR)
                  return (SET_ERROR(ENOTSUP));
  
          ret = nvlist_lookup_uint64(nvl, "mdn_maxblkid", &maxblkid);
          if (ret != 0)
                  return (SET_ERROR(EINVAL));
  
          ret = nvlist_lookup_uint8_array(nvl, "portable_mac", &buf, &len);
          if (ret != 0 || len != ZIO_OBJSET_MAC_LEN)
                  return (SET_ERROR(EINVAL));
  
          ret = dmu_objset_from_ds(ds, &os);
          if (ret != 0)
                  return (ret);
  
          mdn = DMU_META_DNODE(os);
  
          /*
           * If we already created the objset, make sure its unchangeable
           * properties match the ones received in the nvlist.
           */
          rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG);
          if (!BP_IS_HOLE(dsl_dataset_get_blkptr(ds)) &&
              (mdn->dn_nlevels != nlevels || mdn->dn_datablksz != blksz ||
              mdn->dn_indblkshift != ibs || mdn->dn_nblkptr != nblkptr)) {
                  rrw_exit(&ds->ds_bp_rwlock, FTAG);
                  return (SET_ERROR(EINVAL));
          }
          rrw_exit(&ds->ds_bp_rwlock, FTAG);
  
          /*
           * Check that the ivset guid of the fromds matches the one from the
           * send stream. Older versions of the encryption code did not have
           * an ivset guid on the from dataset and did not send one in the
           * stream. For these streams we provide the
           * zfs_disable_ivset_guid_check tunable to allow these datasets to
           * be received with a generated ivset guid.
           */
          if (fromds != NULL && !zfs_disable_ivset_guid_check) {
                  uint64_t from_ivset_guid = 0;
                  intval = 0;
  
                  (void) nvlist_lookup_uint64(nvl, "from_ivset_guid", &intval);
                  (void) zap_lookup(tx->tx_pool->dp_meta_objset,
                      fromds->ds_object, DS_FIELD_IVSET_GUID,
                      sizeof (from_ivset_guid), 1, &from_ivset_guid);
  
                  if (intval == 0 || from_ivset_guid == 0)
                          return (SET_ERROR(ZFS_ERR_FROM_IVSET_GUID_MISSING));
  
                  if (intval != from_ivset_guid)
                          return (SET_ERROR(ZFS_ERR_FROM_IVSET_GUID_MISMATCH));
          }
  
          return (0);
  }
  
  static void
  dsl_crypto_recv_raw_objset_sync(dsl_dataset_t *ds, dmu_objset_type_t ostype,
      nvlist_t *nvl, dmu_tx_t *tx)
  {
          dsl_pool_t *dp = tx->tx_pool;
          objset_t *os;
          dnode_t *mdn;
          zio_t *zio;
          uint8_t *portable_mac;
          uint_t len;
          uint64_t compress, checksum, nlevels, blksz, ibs, maxblkid;
          boolean_t newds = B_FALSE;
  
          VERIFY0(dmu_objset_from_ds(ds, &os));
          mdn = DMU_META_DNODE(os);
  
          /*
           * Fetch the values we need from the nvlist. "to_ivset_guid" must
           * be set on the snapshot, which doesn't exist yet. The receive
           * code will take care of this for us later.
           */
          compress = fnvlist_lookup_uint64(nvl, "mdn_compress");
          checksum = fnvlist_lookup_uint64(nvl, "mdn_checksum");
          nlevels = fnvlist_lookup_uint64(nvl, "mdn_nlevels");
          blksz = fnvlist_lookup_uint64(nvl, "mdn_blksz");
          ibs = fnvlist_lookup_uint64(nvl, "mdn_indblkshift");
          maxblkid = fnvlist_lookup_uint64(nvl, "mdn_maxblkid");
          VERIFY0(nvlist_lookup_uint8_array(nvl, "portable_mac", &portable_mac,
              &len));
  
          /* if we haven't created an objset for the ds yet, do that now */
          rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG);
          if (BP_IS_HOLE(dsl_dataset_get_blkptr(ds))) {
                  (void) dmu_objset_create_impl_dnstats(dp->dp_spa, ds,
                      dsl_dataset_get_blkptr(ds), ostype, nlevels, blksz,
                      ibs, tx);
                  newds = B_TRUE;
          }
          rrw_exit(&ds->ds_bp_rwlock, FTAG);
  
          /*
           * Set the portable MAC. The local MAC will always be zero since the
           * incoming data will all be portable and user accounting will be
           * deferred until the next mount. Afterwards, flag the os to be
           * written out raw next time.
           */
          arc_release(os->os_phys_buf, &os->os_phys_buf);
          memcpy(os->os_phys->os_portable_mac, portable_mac, ZIO_OBJSET_MAC_LEN);
          memset(os->os_phys->os_local_mac, 0, ZIO_OBJSET_MAC_LEN);
          os->os_flags &= ~OBJSET_FLAG_USERACCOUNTING_COMPLETE;
          os->os_next_write_raw[tx->tx_txg & TXG_MASK] = B_TRUE;
  
          /* set metadnode compression and checksum */
          mdn->dn_compress = compress;
          mdn->dn_checksum = checksum;
  
          rw_enter(&mdn->dn_struct_rwlock, RW_WRITER);
          dnode_new_blkid(mdn, maxblkid, tx, B_FALSE, B_TRUE);
          rw_exit(&mdn->dn_struct_rwlock);
  
          /*
           * We can't normally dirty the dataset in syncing context unless
           * we are creating a new dataset. In this case, we perform a
           * pseudo txg sync here instead.
           */
          if (newds) {
                  dsl_dataset_dirty(ds, tx);
          } else {
                  zio = zio_root(dp->dp_spa, NULL, NULL, ZIO_FLAG_MUSTSUCCEED);
                  dsl_dataset_sync(ds, zio, tx);
                  VERIFY0(zio_wait(zio));
  
                  /* dsl_dataset_sync_done will drop this reference. */
                  dmu_buf_add_ref(ds->ds_dbuf, ds);
                  dsl_dataset_sync_done(ds, tx);
          }
  }
  
  int
  dsl_crypto_recv_raw_key_check(dsl_dataset_t *ds, nvlist_t *nvl, dmu_tx_t *tx)
  {
          int ret;
          objset_t *mos = tx->tx_pool->dp_meta_objset;
          uint8_t *buf = NULL;
          uint_t len;
          uint64_t intval, key_guid, version;
          boolean_t is_passphrase = B_FALSE;
  
          ASSERT(dsl_dataset_phys(ds)->ds_flags & DS_FLAG_INCONSISTENT);
  
          /*
           * Read and check all the encryption values from the nvlist. We need
           * all of the fields of a DSL Crypto Key, as well as a fully specified
           * wrapping key.
           */
          ret = nvlist_lookup_uint64(nvl, DSL_CRYPTO_KEY_CRYPTO_SUITE, &intval);
          if (ret != 0 || intval >= ZIO_CRYPT_FUNCTIONS ||
              intval <= ZIO_CRYPT_OFF)
                  return (SET_ERROR(EINVAL));
  
          ret = nvlist_lookup_uint64(nvl, DSL_CRYPTO_KEY_GUID, &intval);
          if (ret != 0)
                  return (SET_ERROR(EINVAL));
  
          /*
           * If this is an incremental receive make sure the given key guid
           * matches the one we already have.
           */
          if (ds->ds_dir->dd_crypto_obj != 0) {
                  ret = zap_lookup(mos, ds->ds_dir->dd_crypto_obj,
                      DSL_CRYPTO_KEY_GUID, 8, 1, &key_guid);
                  if (ret != 0)
                          return (ret);
                  if (intval != key_guid)
                          return (SET_ERROR(EACCES));
          }
  
          ret = nvlist_lookup_uint8_array(nvl, DSL_CRYPTO_KEY_MASTER_KEY,
              &buf, &len);
          if (ret != 0 || len != MASTER_KEY_MAX_LEN)
                  return (SET_ERROR(EINVAL));
  
          ret = nvlist_lookup_uint8_array(nvl, DSL_CRYPTO_KEY_HMAC_KEY,
              &buf, &len);
          if (ret != 0 || len != SHA512_HMAC_KEYLEN)
                  return (SET_ERROR(EINVAL));
  
          ret = nvlist_lookup_uint8_array(nvl, DSL_CRYPTO_KEY_IV, &buf, &len);
          if (ret != 0 || len != WRAPPING_IV_LEN)
                  return (SET_ERROR(EINVAL));
  
          ret = nvlist_lookup_uint8_array(nvl, DSL_CRYPTO_KEY_MAC, &buf, &len);
          if (ret != 0 || len != WRAPPING_MAC_LEN)
                  return (SET_ERROR(EINVAL));
  
          /*
           * We don't support receiving old on-disk formats. The version 0
           * implementation protected several fields in an objset that were
           * not always portable during a raw receive. As a result, we call
           * the old version an on-disk errata #3.
           */
          ret = nvlist_lookup_uint64(nvl, DSL_CRYPTO_KEY_VERSION, &version);
          if (ret != 0 || version != ZIO_CRYPT_KEY_CURRENT_VERSION)
                  return (SET_ERROR(ENOTSUP));
  
          ret = nvlist_lookup_uint64(nvl, zfs_prop_to_name(ZFS_PROP_KEYFORMAT),
              &intval);
          if (ret != 0 || intval >= ZFS_KEYFORMAT_FORMATS ||
              intval == ZFS_KEYFORMAT_NONE)
                  return (SET_ERROR(EINVAL));
  
          is_passphrase = (intval == ZFS_KEYFORMAT_PASSPHRASE);
  
          /*
           * for raw receives we allow any number of pbkdf2iters since there
           * won't be a chance for the user to change it.
           */
          ret = nvlist_lookup_uint64(nvl, zfs_prop_to_name(ZFS_PROP_PBKDF2_ITERS),
              &intval);
          if (ret != 0 || (is_passphrase == (intval == 0)))
                  return (SET_ERROR(EINVAL));
  
          ret = nvlist_lookup_uint64(nvl, zfs_prop_to_name(ZFS_PROP_PBKDF2_SALT),
              &intval);
          if (ret != 0 || (is_passphrase == (intval == 0)))
                  return (SET_ERROR(EINVAL));
  
          return (0);
  }
  
  void
  dsl_crypto_recv_raw_key_sync(dsl_dataset_t *ds, nvlist_t *nvl, dmu_tx_t *tx)
  {
          dsl_pool_t *dp = tx->tx_pool;
          objset_t *mos = dp->dp_meta_objset;
          dsl_dir_t *dd = ds->ds_dir;
          uint_t len;
          uint64_t rddobj, one = 1;
          uint8_t *keydata, *hmac_keydata, *iv, *mac;
          uint64_t crypt, key_guid, keyformat, iters, salt;
          uint64_t version = ZIO_CRYPT_KEY_CURRENT_VERSION;
          const char *keylocation = "prompt";
  
          /* lookup the values we need to create the DSL Crypto Key */
          crypt = fnvlist_lookup_uint64(nvl, DSL_CRYPTO_KEY_CRYPTO_SUITE);
          key_guid = fnvlist_lookup_uint64(nvl, DSL_CRYPTO_KEY_GUID);
          keyformat = fnvlist_lookup_uint64(nvl,
              zfs_prop_to_name(ZFS_PROP_KEYFORMAT));
          iters = fnvlist_lookup_uint64(nvl,
              zfs_prop_to_name(ZFS_PROP_PBKDF2_ITERS));
          salt = fnvlist_lookup_uint64(nvl,
              zfs_prop_to_name(ZFS_PROP_PBKDF2_SALT));
          VERIFY0(nvlist_lookup_uint8_array(nvl, DSL_CRYPTO_KEY_MASTER_KEY,
              &keydata, &len));
          VERIFY0(nvlist_lookup_uint8_array(nvl, DSL_CRYPTO_KEY_HMAC_KEY,
              &hmac_keydata, &len));
          VERIFY0(nvlist_lookup_uint8_array(nvl, DSL_CRYPTO_KEY_IV, &iv, &len));
          VERIFY0(nvlist_lookup_uint8_array(nvl, DSL_CRYPTO_KEY_MAC, &mac, &len));
  
          /* if this is a new dataset setup the DSL Crypto Key. */
          if (dd->dd_crypto_obj == 0) {
                  /* zapify the dsl dir so we can add the key object to it */
                  dmu_buf_will_dirty(dd->dd_dbuf, tx);
                  dsl_dir_zapify(dd, tx);
  
                  /* create the DSL Crypto Key on disk and activate the feature */
                  dd->dd_crypto_obj = zap_create(mos,
                      DMU_OTN_ZAP_METADATA, DMU_OT_NONE, 0, tx);
                  VERIFY0(zap_update(tx->tx_pool->dp_meta_objset,
                      dd->dd_crypto_obj, DSL_CRYPTO_KEY_REFCOUNT,
                      sizeof (uint64_t), 1, &one, tx));
                  VERIFY0(zap_update(tx->tx_pool->dp_meta_objset,
                      dd->dd_crypto_obj, DSL_CRYPTO_KEY_VERSION,
                      sizeof (uint64_t), 1, &version, tx));
  
                  dsl_dataset_activate_feature(ds->ds_object,
                      SPA_FEATURE_ENCRYPTION, (void *)B_TRUE, tx);
                  ds->ds_feature[SPA_FEATURE_ENCRYPTION] = (void *)B_TRUE;
  
                  /* save the dd_crypto_obj on disk */
                  VERIFY0(zap_add(mos, dd->dd_object, DD_FIELD_CRYPTO_KEY_OBJ,
                      sizeof (uint64_t), 1, &dd->dd_crypto_obj, tx));
  
                  /*
                   * Set the keylocation to prompt by default. If keylocation
                   * has been provided via the properties, this will be overridden
                   * later.
                   */
                  dsl_prop_set_sync_impl(ds,
                      zfs_prop_to_name(ZFS_PROP_KEYLOCATION),
                      ZPROP_SRC_LOCAL, 1, strlen(keylocation) + 1,
                      keylocation, tx);
  
                  rddobj = dd->dd_object;
          } else {
                  VERIFY0(dsl_dir_get_encryption_root_ddobj(dd, &rddobj));
          }
  
          /* sync the key data to the ZAP object on disk */
          dsl_crypto_key_sync_impl(mos, dd->dd_crypto_obj, crypt,
              rddobj, key_guid, iv, mac, keydata, hmac_keydata, keyformat, salt,
              iters, tx);
  }
  
  static int
  dsl_crypto_recv_key_check(void *arg, dmu_tx_t *tx)
  {
          int ret;
          dsl_crypto_recv_key_arg_t *dcrka = arg;
          dsl_dataset_t *ds = NULL, *fromds = NULL;
  
          ret = dsl_dataset_hold_obj(tx->tx_pool, dcrka->dcrka_dsobj,
              FTAG, &ds);
          if (ret != 0)
                  goto out;
  
          if (dcrka->dcrka_fromobj != 0) {
                  ret = dsl_dataset_hold_obj(tx->tx_pool, dcrka->dcrka_fromobj,
                      FTAG, &fromds);
                  if (ret != 0)
                          goto out;
          }
  
          ret = dsl_crypto_recv_raw_objset_check(ds, fromds,
              dcrka->dcrka_ostype, dcrka->dcrka_nvl, tx);
          if (ret != 0)
                  goto out;
  
          /*
           * We run this check even if we won't be doing this part of
           * the receive now so that we don't make the user wait until
           * the receive finishes to fail.
           */
          ret = dsl_crypto_recv_raw_key_check(ds, dcrka->dcrka_nvl, tx);
          if (ret != 0)
                  goto out;
  
  out:
          if (ds != NULL)
                  dsl_dataset_rele(ds, FTAG);
          if (fromds != NULL)
                  dsl_dataset_rele(fromds, FTAG);
          return (ret);
  }
  
  static void
  dsl_crypto_recv_key_sync(void *arg, dmu_tx_t *tx)
  {
          dsl_crypto_recv_key_arg_t *dcrka = arg;
          dsl_dataset_t *ds;
  
          VERIFY0(dsl_dataset_hold_obj(tx->tx_pool, dcrka->dcrka_dsobj,
              FTAG, &ds));
          dsl_crypto_recv_raw_objset_sync(ds, dcrka->dcrka_ostype,
              dcrka->dcrka_nvl, tx);
          if (dcrka->dcrka_do_key)
                  dsl_crypto_recv_raw_key_sync(ds, dcrka->dcrka_nvl, tx);
          dsl_dataset_rele(ds, FTAG);
  }
  
  /*
   * This function is used to sync an nvlist representing a DSL Crypto Key and
   * the associated encryption parameters. The key will be written exactly as is
   * without wrapping it.
   */
  int
  dsl_crypto_recv_raw(const char *poolname, uint64_t dsobj, uint64_t fromobj,
      dmu_objset_type_t ostype, nvlist_t *nvl, boolean_t do_key)
  {
          dsl_crypto_recv_key_arg_t dcrka;
  
          dcrka.dcrka_dsobj = dsobj;
          dcrka.dcrka_fromobj = fromobj;
          dcrka.dcrka_ostype = ostype;
          dcrka.dcrka_nvl = nvl;
          dcrka.dcrka_do_key = do_key;
  
          return (dsl_sync_task(poolname, dsl_crypto_recv_key_check,
              dsl_crypto_recv_key_sync, &dcrka, 1, ZFS_SPACE_CHECK_NORMAL));
  }
  
  int
  dsl_crypto_populate_key_nvlist(objset_t *os, uint64_t from_ivset_guid,
      nvlist_t **nvl_out)
  {
          int ret;
          dsl_dataset_t *ds = os->os_dsl_dataset;
          dnode_t *mdn;
          uint64_t rddobj;
          nvlist_t *nvl = NULL;
          uint64_t dckobj = ds->ds_dir->dd_crypto_obj;
          dsl_dir_t *rdd = NULL;
          dsl_pool_t *dp = ds->ds_dir->dd_pool;
          objset_t *mos = dp->dp_meta_objset;
          uint64_t crypt = 0, key_guid = 0, format = 0;
          uint64_t iters = 0, salt = 0, version = 0;
          uint64_t to_ivset_guid = 0;
          uint8_t raw_keydata[MASTER_KEY_MAX_LEN];
          uint8_t raw_hmac_keydata[SHA512_HMAC_KEYLEN];
          uint8_t iv[WRAPPING_IV_LEN];
          uint8_t mac[WRAPPING_MAC_LEN];
  
          ASSERT(dckobj != 0);
  
          mdn = DMU_META_DNODE(os);
  
          nvl = fnvlist_alloc();
  
          /* lookup values from the DSL Crypto Key */
          ret = zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_CRYPTO_SUITE, 8, 1,
              &crypt);
          if (ret != 0)
                  goto error;
  
          ret = zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_GUID, 8, 1, &key_guid);
          if (ret != 0)
                  goto error;
  
          ret = zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_MASTER_KEY, 1,
              MASTER_KEY_MAX_LEN, raw_keydata);
          if (ret != 0)
                  goto error;
  
          ret = zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_HMAC_KEY, 1,
              SHA512_HMAC_KEYLEN, raw_hmac_keydata);
          if (ret != 0)
                  goto error;
  
          ret = zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_IV, 1, WRAPPING_IV_LEN,
              iv);
          if (ret != 0)
                  goto error;
  
          ret = zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_MAC, 1, WRAPPING_MAC_LEN,
              mac);
          if (ret != 0)
                  goto error;
  
          /* see zfs_disable_ivset_guid_check tunable for errata info */
          ret = zap_lookup(mos, ds->ds_object, DS_FIELD_IVSET_GUID, 8, 1,
              &to_ivset_guid);
          if (ret != 0)
                  ASSERT3U(dp->dp_spa->spa_errata, !=, 0);
  
          /*
           * We don't support raw sends of legacy on-disk formats. See the
           * comment in dsl_crypto_recv_key_check() for details.
           */
          ret = zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_VERSION, 8, 1, &version);
          if (ret != 0 || version != ZIO_CRYPT_KEY_CURRENT_VERSION) {
                  dp->dp_spa->spa_errata = ZPOOL_ERRATA_ZOL_6845_ENCRYPTION;
                  ret = SET_ERROR(ENOTSUP);
                  goto error;
          }
  
          /*
           * Lookup wrapping key properties. An early version of the code did
           * not correctly add these values to the wrapping key or the DSL
           * Crypto Key on disk for non encryption roots, so to be safe we
           * always take the slightly circuitous route of looking it up from
           * the encryption root's key.
           */
          ret = dsl_dir_get_encryption_root_ddobj(ds->ds_dir, &rddobj);
          if (ret != 0)
                  goto error;
  
          dsl_pool_config_enter(dp, FTAG);
  
          ret = dsl_dir_hold_obj(dp, rddobj, NULL, FTAG, &rdd);
          if (ret != 0)
                  goto error_unlock;
  
          ret = zap_lookup(dp->dp_meta_objset, rdd->dd_crypto_obj,
              zfs_prop_to_name(ZFS_PROP_KEYFORMAT), 8, 1, &format);
          if (ret != 0)
                  goto error_unlock;
  
          if (format == ZFS_KEYFORMAT_PASSPHRASE) {
                  ret = zap_lookup(dp->dp_meta_objset, rdd->dd_crypto_obj,
                      zfs_prop_to_name(ZFS_PROP_PBKDF2_ITERS), 8, 1, &iters);
                  if (ret != 0)
                          goto error_unlock;
  
                  ret = zap_lookup(dp->dp_meta_objset, rdd->dd_crypto_obj,
                      zfs_prop_to_name(ZFS_PROP_PBKDF2_SALT), 8, 1, &salt);
                  if (ret != 0)
                          goto error_unlock;
          }
  
          dsl_dir_rele(rdd, FTAG);
          dsl_pool_config_exit(dp, FTAG);
  
          fnvlist_add_uint64(nvl, DSL_CRYPTO_KEY_CRYPTO_SUITE, crypt);
          fnvlist_add_uint64(nvl, DSL_CRYPTO_KEY_GUID, key_guid);
          fnvlist_add_uint64(nvl, DSL_CRYPTO_KEY_VERSION, version);
          VERIFY0(nvlist_add_uint8_array(nvl, DSL_CRYPTO_KEY_MASTER_KEY,
              raw_keydata, MASTER_KEY_MAX_LEN));
          VERIFY0(nvlist_add_uint8_array(nvl, DSL_CRYPTO_KEY_HMAC_KEY,
              raw_hmac_keydata, SHA512_HMAC_KEYLEN));
          VERIFY0(nvlist_add_uint8_array(nvl, DSL_CRYPTO_KEY_IV, iv,
              WRAPPING_IV_LEN));
          VERIFY0(nvlist_add_uint8_array(nvl, DSL_CRYPTO_KEY_MAC, mac,
              WRAPPING_MAC_LEN));
          VERIFY0(nvlist_add_uint8_array(nvl, "portable_mac",
              os->os_phys->os_portable_mac, ZIO_OBJSET_MAC_LEN));
          fnvlist_add_uint64(nvl, zfs_prop_to_name(ZFS_PROP_KEYFORMAT), format);
          fnvlist_add_uint64(nvl, zfs_prop_to_name(ZFS_PROP_PBKDF2_ITERS), iters);
          fnvlist_add_uint64(nvl, zfs_prop_to_name(ZFS_PROP_PBKDF2_SALT), salt);
          fnvlist_add_uint64(nvl, "mdn_checksum", mdn->dn_checksum);
          fnvlist_add_uint64(nvl, "mdn_compress", mdn->dn_compress);
          fnvlist_add_uint64(nvl, "mdn_nlevels", mdn->dn_nlevels);
          fnvlist_add_uint64(nvl, "mdn_blksz", mdn->dn_datablksz);
          fnvlist_add_uint64(nvl, "mdn_indblkshift", mdn->dn_indblkshift);
          fnvlist_add_uint64(nvl, "mdn_nblkptr", mdn->dn_nblkptr);
          fnvlist_add_uint64(nvl, "mdn_maxblkid", mdn->dn_maxblkid);
          fnvlist_add_uint64(nvl, "to_ivset_guid", to_ivset_guid);
          fnvlist_add_uint64(nvl, "from_ivset_guid", from_ivset_guid);
  
          *nvl_out = nvl;
          return (0);
  
  error_unlock:
          dsl_pool_config_exit(dp, FTAG);
  error:
          if (rdd != NULL)
                  dsl_dir_rele(rdd, FTAG);
          nvlist_free(nvl);
  
          *nvl_out = NULL;
          return (ret);
  }
  
  uint64_t
  dsl_crypto_key_create_sync(uint64_t crypt, dsl_wrapping_key_t *wkey,
      dmu_tx_t *tx)
  {
          dsl_crypto_key_t dck;
          uint64_t version = ZIO_CRYPT_KEY_CURRENT_VERSION;
          uint64_t one = 1ULL;
  
          ASSERT(dmu_tx_is_syncing(tx));
          ASSERT3U(crypt, <, ZIO_CRYPT_FUNCTIONS);
          ASSERT3U(crypt, >, ZIO_CRYPT_OFF);
  
          /* create the DSL Crypto Key ZAP object */
          dck.dck_obj = zap_create(tx->tx_pool->dp_meta_objset,
              DMU_OTN_ZAP_METADATA, DMU_OT_NONE, 0, tx);
  
          /* fill in the key (on the stack) and sync it to disk */
          dck.dck_wkey = wkey;
          VERIFY0(zio_crypt_key_init(crypt, &dck.dck_key));
  
          dsl_crypto_key_sync(&dck, tx);
          VERIFY0(zap_update(tx->tx_pool->dp_meta_objset, dck.dck_obj,
              DSL_CRYPTO_KEY_REFCOUNT, sizeof (uint64_t), 1, &one, tx));
          VERIFY0(zap_update(tx->tx_pool->dp_meta_objset, dck.dck_obj,
              DSL_CRYPTO_KEY_VERSION, sizeof (uint64_t), 1, &version, tx));
  
          zio_crypt_key_destroy(&dck.dck_key);
          memset(&dck.dck_key, 0, sizeof (zio_crypt_key_t));
  
          return (dck.dck_obj);
  }
  
  uint64_t
  dsl_crypto_key_clone_sync(dsl_dir_t *origindd, dmu_tx_t *tx)
  {
          objset_t *mos = tx->tx_pool->dp_meta_objset;
  
          ASSERT(dmu_tx_is_syncing(tx));
  
          VERIFY0(zap_increment(mos, origindd->dd_crypto_obj,
              DSL_CRYPTO_KEY_REFCOUNT, 1, tx));
  
          return (origindd->dd_crypto_obj);
  }
  
  void
  dsl_crypto_key_destroy_sync(uint64_t dckobj, dmu_tx_t *tx)
  {
          objset_t *mos = tx->tx_pool->dp_meta_objset;
          uint64_t refcnt;
  
          /* Decrement the refcount, destroy if this is the last reference */
          VERIFY0(zap_lookup(mos, dckobj, DSL_CRYPTO_KEY_REFCOUNT,
              sizeof (uint64_t), 1, &refcnt));
  
          if (refcnt != 1) {
                  VERIFY0(zap_increment(mos, dckobj, DSL_CRYPTO_KEY_REFCOUNT,
                      -1, tx));
          } else {
                  VERIFY0(zap_destroy(mos, dckobj, tx));
          }
  }
  
  void
  dsl_dataset_crypt_stats(dsl_dataset_t *ds, nvlist_t *nv)
  {
          uint64_t intval;
          dsl_dir_t *dd = ds->ds_dir;
          dsl_dir_t *enc_root;
          char buf[ZFS_MAX_DATASET_NAME_LEN];
  
          if (dd->dd_crypto_obj == 0)
                  return;
  
          intval = dsl_dataset_get_keystatus(dd);
          dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_KEYSTATUS, intval);
  
          if (dsl_dir_get_crypt(dd, &intval) == 0)
                  dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_ENCRYPTION, intval);
          if (zap_lookup(dd->dd_pool->dp_meta_objset, dd->dd_crypto_obj,
              DSL_CRYPTO_KEY_GUID, 8, 1, &intval) == 0) {
                  dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_KEY_GUID, intval);
          }
          if (zap_lookup(dd->dd_pool->dp_meta_objset, dd->dd_crypto_obj,
              zfs_prop_to_name(ZFS_PROP_KEYFORMAT), 8, 1, &intval) == 0) {
                  dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_KEYFORMAT, intval);
          }
          if (zap_lookup(dd->dd_pool->dp_meta_objset, dd->dd_crypto_obj,
              zfs_prop_to_name(ZFS_PROP_PBKDF2_SALT), 8, 1, &intval) == 0) {
                  dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_PBKDF2_SALT, intval);
          }
          if (zap_lookup(dd->dd_pool->dp_meta_objset, dd->dd_crypto_obj,
              zfs_prop_to_name(ZFS_PROP_PBKDF2_ITERS), 8, 1, &intval) == 0) {
                  dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_PBKDF2_ITERS, intval);
          }
          if (zap_lookup(dd->dd_pool->dp_meta_objset, ds->ds_object,
              DS_FIELD_IVSET_GUID, 8, 1, &intval) == 0) {
                  dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_IVSET_GUID, intval);
          }
  
          if (dsl_dir_get_encryption_root_ddobj(dd, &intval) == 0) {
                  if (dsl_dir_hold_obj(dd->dd_pool, intval, NULL, FTAG,
                      &enc_root) == 0) {
                          dsl_dir_name(enc_root, buf);
                          dsl_dir_rele(enc_root, FTAG);
                          dsl_prop_nvlist_add_string(nv,
                              ZFS_PROP_ENCRYPTION_ROOT, buf);
                  }
          }
  }
  
  int
  spa_crypt_get_salt(spa_t *spa, uint64_t dsobj, uint8_t *salt)
  {
          int ret;
          dsl_crypto_key_t *dck = NULL;
  
          /* look up the key from the spa's keystore */
          ret = spa_keystore_lookup_key(spa, dsobj, FTAG, &dck);
          if (ret != 0)
                  goto error;
  
          ret = zio_crypt_key_get_salt(&dck->dck_key, salt);
          if (ret != 0)
                  goto error;
  
          spa_keystore_dsl_key_rele(spa, dck, FTAG);
          return (0);
  
  error:
          if (dck != NULL)
                  spa_keystore_dsl_key_rele(spa, dck, FTAG);
          return (ret);
  }
  
  /*
   * Objset blocks are a special case for MAC generation. These blocks have 2
   * 256-bit MACs which are embedded within the block itself, rather than a
   * single 128 bit MAC. As a result, this function handles encoding and decoding
   * the MACs on its own, unlike other functions in this file.
   */
  int
  spa_do_crypt_objset_mac_abd(boolean_t generate, spa_t *spa, uint64_t dsobj,
      abd_t *abd, uint_t datalen, boolean_t byteswap)
  {
          int ret;
          dsl_crypto_key_t *dck = NULL;
          void *buf = abd_borrow_buf_copy(abd, datalen);
          objset_phys_t *osp = buf;
          uint8_t portable_mac[ZIO_OBJSET_MAC_LEN];
          uint8_t local_mac[ZIO_OBJSET_MAC_LEN];
          const uint8_t zeroed_mac[ZIO_OBJSET_MAC_LEN] = {0};
  
          /* look up the key from the spa's keystore */
          ret = spa_keystore_lookup_key(spa, dsobj, FTAG, &dck);
          if (ret != 0)
                  goto error;
  
          /* calculate both HMACs */
          ret = zio_crypt_do_objset_hmacs(&dck->dck_key, buf, datalen,
              byteswap, portable_mac, local_mac);
          if (ret != 0)
                  goto error;
  
          spa_keystore_dsl_key_rele(spa, dck, FTAG);
  
          /* if we are generating encode the HMACs in the objset_phys_t */
          if (generate) {
                  memcpy(osp->os_portable_mac, portable_mac, ZIO_OBJSET_MAC_LEN);
                  memcpy(osp->os_local_mac, local_mac, ZIO_OBJSET_MAC_LEN);
                  abd_return_buf_copy(abd, buf, datalen);
                  return (0);
          }
  
          if (memcmp(portable_mac, osp->os_portable_mac,
              ZIO_OBJSET_MAC_LEN) != 0 ||
              memcmp(local_mac, osp->os_local_mac, ZIO_OBJSET_MAC_LEN) != 0) {
                  /*
                   * If the MAC is zeroed out, we failed to decrypt it.
                   * This should only arise, at least on Linux,
                   * if we hit edge case handling for useraccounting, since we
                   * shouldn't get here without bailing out on error earlier
                   * otherwise.
                   *
                   * So if we're in that case, we can just fall through and
                   * special-casing noticing that it's zero will handle it
                   * elsewhere, since we can just regenerate it.
                   */
                  if (memcmp(local_mac, zeroed_mac, ZIO_OBJSET_MAC_LEN) != 0) {
                          abd_return_buf(abd, buf, datalen);
                          return (SET_ERROR(ECKSUM));
                  }
          }
  
          abd_return_buf(abd, buf, datalen);
  
          return (0);
  
  error:
          if (dck != NULL)
                  spa_keystore_dsl_key_rele(spa, dck, FTAG);
          abd_return_buf(abd, buf, datalen);
          return (ret);
  }
  
  int
  spa_do_crypt_mac_abd(boolean_t generate, spa_t *spa, uint64_t dsobj, abd_t *abd,
      uint_t datalen, uint8_t *mac)
  {
          int ret;
          dsl_crypto_key_t *dck = NULL;
          uint8_t *buf = abd_borrow_buf_copy(abd, datalen);
          uint8_t digestbuf[ZIO_DATA_MAC_LEN];
  
          /* look up the key from the spa's keystore */
          ret = spa_keystore_lookup_key(spa, dsobj, FTAG, &dck);
          if (ret != 0)
                  goto error;
  
          /* perform the hmac */
          ret = zio_crypt_do_hmac(&dck->dck_key, buf, datalen,
              digestbuf, ZIO_DATA_MAC_LEN);
          if (ret != 0)
                  goto error;
  
          abd_return_buf(abd, buf, datalen);
          spa_keystore_dsl_key_rele(spa, dck, FTAG);
  
          /*
           * Truncate and fill in mac buffer if we were asked to generate a MAC.
           * Otherwise verify that the MAC matched what we expected.
           */
          if (generate) {
                  memcpy(mac, digestbuf, ZIO_DATA_MAC_LEN);
                  return (0);
          }
  
          if (memcmp(digestbuf, mac, ZIO_DATA_MAC_LEN) != 0)
                  return (SET_ERROR(ECKSUM));
  
          return (0);
  
  error:
          if (dck != NULL)
                  spa_keystore_dsl_key_rele(spa, dck, FTAG);
          abd_return_buf(abd, buf, datalen);
          return (ret);
  }
  
  /*
   * This function serves as a multiplexer for encryption and decryption of
   * all blocks (except the L2ARC). For encryption, it will populate the IV,
   * salt, MAC, and cabd (the ciphertext). On decryption it will simply use
   * these fields to populate pabd (the plaintext).
   */
  int
  spa_do_crypt_abd(boolean_t encrypt, spa_t *spa, const zbookmark_phys_t *zb,
      dmu_object_type_t ot, boolean_t dedup, boolean_t bswap, uint8_t *salt,
      uint8_t *iv, uint8_t *mac, uint_t datalen, abd_t *pabd, abd_t *cabd,
      boolean_t *no_crypt)
  {
          int ret;
          dsl_crypto_key_t *dck = NULL;
          uint8_t *plainbuf = NULL, *cipherbuf = NULL;
  
          ASSERT(spa_feature_is_active(spa, SPA_FEATURE_ENCRYPTION));
  
          /* look up the key from the spa's keystore */
          ret = spa_keystore_lookup_key(spa, zb->zb_objset, FTAG, &dck);
          if (ret != 0) {
                  ret = SET_ERROR(EACCES);
                  return (ret);
          }
  
          if (encrypt) {
                  plainbuf = abd_borrow_buf_copy(pabd, datalen);
                  cipherbuf = abd_borrow_buf(cabd, datalen);
          } else {
                  plainbuf = abd_borrow_buf(pabd, datalen);
                  cipherbuf = abd_borrow_buf_copy(cabd, datalen);
          }
  
          /*
           * Both encryption and decryption functions need a salt for key
           * generation and an IV. When encrypting a non-dedup block, we
           * generate the salt and IV randomly to be stored by the caller. Dedup
           * blocks perform a (more expensive) HMAC of the plaintext to obtain
           * the salt and the IV. ZIL blocks have their salt and IV generated
           * at allocation time in zio_alloc_zil(). On decryption, we simply use
           * the provided values.
           */
          if (encrypt && ot != DMU_OT_INTENT_LOG && !dedup) {
                  ret = zio_crypt_key_get_salt(&dck->dck_key, salt);
                  if (ret != 0)
                          goto error;
  
                  ret = zio_crypt_generate_iv(iv);
                  if (ret != 0)
                          goto error;
          } else if (encrypt && dedup) {
                  ret = zio_crypt_generate_iv_salt_dedup(&dck->dck_key,
                      plainbuf, datalen, iv, salt);
                  if (ret != 0)
                          goto error;
          }
  
          /* call lower level function to perform encryption / decryption */
          ret = zio_do_crypt_data(encrypt, &dck->dck_key, ot, bswap, salt, iv,
              mac, datalen, plainbuf, cipherbuf, no_crypt);
  
          /*
           * Handle injected decryption faults. Unfortunately, we cannot inject
           * faults for dnode blocks because we might trigger the panic in
           * dbuf_prepare_encrypted_dnode_leaf(), which exists because syncing
           * context is not prepared to handle malicious decryption failures.
           */
          if (zio_injection_enabled && !encrypt && ot != DMU_OT_DNODE && ret == 0)
                  ret = zio_handle_decrypt_injection(spa, zb, ot, ECKSUM);
          if (ret != 0)
                  goto error;
  
          if (encrypt) {
                  abd_return_buf(pabd, plainbuf, datalen);
                  abd_return_buf_copy(cabd, cipherbuf, datalen);
          } else {
                  abd_return_buf_copy(pabd, plainbuf, datalen);
                  abd_return_buf(cabd, cipherbuf, datalen);
          }
  
          spa_keystore_dsl_key_rele(spa, dck, FTAG);
  
          return (0);
  
  error:
          if (encrypt) {
                  /* zero out any state we might have changed while encrypting */
                  memset(salt, 0, ZIO_DATA_SALT_LEN);
                  memset(iv, 0, ZIO_DATA_IV_LEN);
                  memset(mac, 0, ZIO_DATA_MAC_LEN);
                  abd_return_buf(pabd, plainbuf, datalen);
                  abd_return_buf_copy(cabd, cipherbuf, datalen);
          } else {
                  abd_return_buf_copy(pabd, plainbuf, datalen);
                  abd_return_buf(cabd, cipherbuf, datalen);
          }
  
          spa_keystore_dsl_key_rele(spa, dck, FTAG);
  
          return (ret);
  }
  
  ZFS_MODULE_PARAM(zfs, zfs_, disable_ivset_guid_check, INT, ZMOD_RW,
          "Set to allow raw receives without IVset guids");

Cache object: 8c324347ecc8149d418b204780f1099d