Allow unencrypted children of encrypted datasets

When encryption was first added to ZFS, we made a decision to
prevent users from creating unencrypted children of encrypted
datasets. The idea was to prevent users from inadvertently
leaving some of their data unencrypted. However, since the
release of 0.8.0, some legitimate reasons have been brought up
for this behavior to be allowed. This patch simply removes this
limitation from all code paths that had checks for it and updates
the tests accordingly.

Reviewed-by: Jason King <[email protected]>
Reviewed-by: Sean Eric Fagan <[email protected]>
Reviewed-by: Richard Laager <[email protected]>
Reviewed-by: Brian Behlendorf <[email protected]>
Signed-off-by: Tom Caputi <[email protected]>
Closes #8737 
Closes #8870 

1 files changed, 1 insertions, 40 deletions

diff --git a/lib/libzfs/libzfs_crypto.c b/lib/libzfs/libzfs_crypto.c
index 3318a6bd2..d31f43b1f 100644
--- a/lib/libzfs/libzfs_crypto.c
+++ b/lib/libzfs/libzfs_crypto.c
@@ -740,14 +740,6 @@ zfs_crypto_create(libzfs_handle_t *hdl, char *parent_name, nvlist_t *props,
 		pcrypt = ZIO_CRYPT_OFF;
 	}
 
-	/* Check for encryption being explicitly truned off */
-	if (crypt == ZIO_CRYPT_OFF && pcrypt != ZIO_CRYPT_OFF) {
-		ret = EINVAL;
-		zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
-		    "Invalid encryption value. Dataset must be encrypted."));
-		goto out;
-	}
-
 	/* Get the inherited encryption property if we don't have it locally */
 	if (!local_crypt)
 		crypt = pcrypt;
@@ -849,10 +841,7 @@ int
 zfs_crypto_clone_check(libzfs_handle_t *hdl, zfs_handle_t *origin_zhp,
     char *parent_name, nvlist_t *props)
 {
-	int ret;
 	char errbuf[1024];
-	zfs_handle_t *pzhp = NULL;
-	uint64_t pcrypt, ocrypt;
 
 	(void) snprintf(errbuf, sizeof (errbuf),
 	    dgettext(TEXT_DOMAIN, "Encryption clone error"));
@@ -865,40 +854,12 @@ zfs_crypto_clone_check(libzfs_handle_t *hdl, zfs_handle_t *origin_zhp,
 	    nvlist_exists(props, zfs_prop_to_name(ZFS_PROP_KEYLOCATION)) ||
 	    nvlist_exists(props, zfs_prop_to_name(ZFS_PROP_ENCRYPTION)) ||
 	    nvlist_exists(props, zfs_prop_to_name(ZFS_PROP_PBKDF2_ITERS))) {
-		ret = EINVAL;
 		zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 		    "Encryption properties must inherit from origin dataset."));
-		goto out;
-	}
-
-	/* get a reference to parent dataset, should never be NULL */
-	pzhp = make_dataset_handle(hdl, parent_name);
-	if (pzhp == NULL) {
-		zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
-		    "Failed to lookup parent."));
-		return (ENOENT);
+		return (EINVAL);
 	}
 
-	/* Lookup parent's crypt */
-	pcrypt = zfs_prop_get_int(pzhp, ZFS_PROP_ENCRYPTION);
-	ocrypt = zfs_prop_get_int(origin_zhp, ZFS_PROP_ENCRYPTION);
-
-	/* all children of encrypted parents must be encrypted */
-	if (pcrypt != ZIO_CRYPT_OFF && ocrypt == ZIO_CRYPT_OFF) {
-		ret = EINVAL;
-		zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
-		    "Cannot create unencrypted clone as a child "
-		    "of encrypted parent."));
-		goto out;
-	}
-
-	zfs_close(pzhp);
 	return (0);
-
-out:
-	if (pzhp != NULL)
-		zfs_close(pzhp);
-	return (ret);
 }
 
 typedef struct loadkeys_cbdata {