Native Encryption for ZFS on Linux

This change incorporates three major pieces:

The first change is a keystore that manages wrapping
and encryption keys for encrypted datasets. These
commands mostly involve manipulating the new
DSL Crypto Key ZAP Objects that live in the MOS. Each
encrypted dataset has its own DSL Crypto Key that is
protected with a user's key. This level of indirection
allows users to change their keys without re-encrypting
their entire datasets. The change implements the new
subcommands "zfs load-key", "zfs unload-key" and
"zfs change-key" which allow the user to manage their
encryption keys and settings. In addition, several new
flags and properties have been added to allow dataset
creation and to make mounting and unmounting more
convenient.

The second piece of this patch provides the ability to
encrypt, decyrpt, and authenticate protected datasets.
Each object set maintains a Merkel tree of Message
Authentication Codes that protect the lower layers,
similarly to how checksums are maintained. This part
impacts the zio layer, which handles the actual
encryption and generation of MACs, as well as the ARC
and DMU, which need to be able to handle encrypted
buffers and protected data.

The last addition is the ability to do raw, encrypted
sends and receives. The idea here is to send raw
encrypted and compressed data and receive it exactly
as is on a backup system. This means that the dataset
on the receiving system is protected using the same
user key that is in use on the sending side. By doing
so, datasets can be efficiently backed up to an
untrusted system without fear of data being
compromised.

Reviewed by: Matthew Ahrens <[email protected]>
Reviewed-by: Brian Behlendorf <[email protected]>
Reviewed-by: Jorgen Lundman <[email protected]>
Signed-off-by: Tom Caputi <[email protected]>
Closes #494 
Closes #5769 

1 files changed, 24 insertions, 5 deletions

diff --git a/include/sys/dmu_objset.h b/include/sys/dmu_objset.h
index a836e0372..11b8fc625 100644
--- a/include/sys/dmu_objset.h
+++ b/include/sys/dmu_objset.h
@@ -58,13 +58,19 @@ struct dmu_tx;
 #define	OBJSET_FLAG_USERACCOUNTING_COMPLETE	(1ULL<<0)
 #define	OBJSET_FLAG_USEROBJACCOUNTING_COMPLETE	(1ULL<<1)
 
+/* all flags are currently non-portable */
+#define	OBJSET_CRYPT_PORTABLE_FLAGS_MASK	(0)
+
 typedef struct objset_phys {
 	dnode_phys_t os_meta_dnode;
 	zil_header_t os_zil_header;
 	uint64_t os_type;
 	uint64_t os_flags;
+	uint8_t os_portable_mac[ZIO_OBJSET_MAC_LEN];
+	uint8_t os_local_mac[ZIO_OBJSET_MAC_LEN];
 	char os_pad[OBJSET_PHYS_SIZE - sizeof (dnode_phys_t)*3 -
-	    sizeof (zil_header_t) - sizeof (uint64_t)*2];
+	    sizeof (zil_header_t) - sizeof (uint64_t)*2 -
+	    2*ZIO_OBJSET_MAC_LEN];
 	dnode_phys_t os_userused_dnode;
 	dnode_phys_t os_groupused_dnode;
 } objset_phys_t;
@@ -77,6 +83,8 @@ struct objset {
 	spa_t *os_spa;
 	arc_buf_t *os_phys_buf;
 	objset_phys_t *os_phys;
+	boolean_t os_encrypted;
+
 	/*
 	 * The following "special" dnodes have no parent, are exempt
 	 * from dnode_move(), and are not recorded in os_dnodes, but they
@@ -118,6 +126,9 @@ struct objset {
 	uint64_t os_freed_dnodes;
 	boolean_t os_rescan_dnodes;
 
+	/* os_phys_buf should be written raw next txg */
+	boolean_t os_next_write_raw;
+
 	/* Protected by os_obj_lock */
 	kmutex_t os_obj_lock;
 	uint64_t os_obj_next_chunk;
@@ -161,13 +172,18 @@ struct objset {
 
 /* called from zpl */
 int dmu_objset_hold(const char *name, void *tag, objset_t **osp);
+int dmu_objset_hold_flags(const char *name, boolean_t decrypt, void *tag,
+    objset_t **osp);
 int dmu_objset_own(const char *name, dmu_objset_type_t type,
-    boolean_t readonly, void *tag, objset_t **osp);
+    boolean_t readonly, boolean_t decrypt, void *tag, objset_t **osp);
 int dmu_objset_own_obj(struct dsl_pool *dp, uint64_t obj,
-    dmu_objset_type_t type, boolean_t readonly, void *tag, objset_t **osp);
-void dmu_objset_refresh_ownership(objset_t *os, void *tag);
+    dmu_objset_type_t type, boolean_t readonly, boolean_t decrypt,
+    void *tag, objset_t **osp);
+void dmu_objset_refresh_ownership(objset_t *os, boolean_t key_needed,
+    void *tag);
 void dmu_objset_rele(objset_t *os, void *tag);
-void dmu_objset_disown(objset_t *os, void *tag);
+void dmu_objset_rele_flags(objset_t *os, boolean_t decrypt, void *tag);
+void dmu_objset_disown(objset_t *os, boolean_t decrypt, void *tag);
 int dmu_objset_from_ds(struct dsl_dataset *ds, objset_t **osp);
 
 void dmu_objset_stats(objset_t *os, nvlist_t *nv);
@@ -184,6 +200,9 @@ timestruc_t dmu_objset_snap_cmtime(objset_t *os);
 /* called from dsl */
 void dmu_objset_sync(objset_t *os, zio_t *zio, dmu_tx_t *tx);
 boolean_t dmu_objset_is_dirty(objset_t *os, uint64_t txg);
+objset_t *dmu_objset_create_impl_dnstats(spa_t *spa, struct dsl_dataset *ds,
+    blkptr_t *bp, dmu_objset_type_t type, int levels, int blksz, int ibs,
+    dmu_tx_t *tx);
 objset_t *dmu_objset_create_impl(spa_t *spa, struct dsl_dataset *ds,
     blkptr_t *bp, dmu_objset_type_t type, dmu_tx_t *tx);
 int dmu_objset_open_impl(spa_t *spa, struct dsl_dataset *ds, blkptr_t *bp,