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, 56 insertions, 10 deletions

diff --git a/cmd/zpool/zpool_main.c b/cmd/zpool/zpool_main.c
index 60713197d..3ffd13c8e 100644
--- a/cmd/zpool/zpool_main.c
+++ b/cmd/zpool/zpool_main.c
@@ -55,7 +55,7 @@
 #include <sys/fm/util.h>
 #include <sys/fm/protocol.h>
 #include <sys/zfs_ioctl.h>
-
+#include <sys/mount.h>
 #include <math.h>
 
 #include <libzfs.h>
@@ -313,12 +313,13 @@ get_usage(zpool_help_t idx)
 		return (gettext("\thistory [-il] [<pool>] ...\n"));
 	case HELP_IMPORT:
 		return (gettext("\timport [-d dir] [-D]\n"
-		    "\timport [-d dir | -c cachefile] [-F [-n]] <pool | id>\n"
+		    "\timport [-d dir | -c cachefile] [-F [-n]] [-l] "
+		    "<pool | id>\n"
 		    "\timport [-o mntopts] [-o property=value] ... \n"
-		    "\t    [-d dir | -c cachefile] [-D] [-f] [-m] [-N] "
+		    "\t    [-d dir | -c cachefile] [-D] [-l] [-f] [-m] [-N] "
 		    "[-R root] [-F [-n]] -a\n"
 		    "\timport [-o mntopts] [-o property=value] ... \n"
-		    "\t    [-d dir | -c cachefile] [-D] [-f] [-m] [-N] "
+		    "\t    [-d dir | -c cachefile] [-D] [-l] [-f] [-m] [-N] "
 		    "[-R root] [-F [-n]]\n"
 		    "\t    <pool | id> [newpool]\n"));
 	case HELP_IOSTAT:
@@ -359,7 +360,7 @@ get_usage(zpool_help_t idx)
 	case HELP_SET:
 		return (gettext("\tset <property=value> <pool> \n"));
 	case HELP_SPLIT:
-		return (gettext("\tsplit [-gLnP] [-R altroot] [-o mntopts]\n"
+		return (gettext("\tsplit [-gLnPl] [-R altroot] [-o mntopts]\n"
 		    "\t    [-o property=value] <pool> <newpool> "
 		    "[<device> ...]\n"));
 	case HELP_REGUID:
@@ -2261,6 +2262,7 @@ static int
 do_import(nvlist_t *config, const char *newname, const char *mntopts,
     nvlist_t *props, int flags)
 {
+	int ret = 0;
 	zpool_handle_t *zhp;
 	char *name;
 	uint64_t state;
@@ -2343,6 +2345,16 @@ do_import(nvlist_t *config, const char *newname, const char *mntopts,
 	if ((zhp = zpool_open_canfail(g_zfs, name)) == NULL)
 		return (1);
 
+	/*
+	 * Loading keys is best effort. We don't want to return immediately
+	 * if it fails but we do want to give the error to the caller.
+	 */
+	if (flags & ZFS_IMPORT_LOAD_KEYS) {
+		ret = zfs_crypto_attempt_load_keys(g_zfs, name);
+		if (ret != 0)
+			ret = 1;
+	}
+
 	if (zpool_get_state(zhp) != POOL_STATE_UNAVAIL &&
 	    !(flags & ZFS_IMPORT_ONLY) &&
 	    zpool_enable_datasets(zhp, mntopts, 0) != 0) {
@@ -2351,14 +2363,14 @@ do_import(nvlist_t *config, const char *newname, const char *mntopts,
 	}
 
 	zpool_close(zhp);
-	return (0);
+	return (ret);
 }
 
 /*
  * zpool import [-d dir] [-D]
- *       import [-o mntopts] [-o prop=value] ... [-R root] [-D]
+ *       import [-o mntopts] [-o prop=value] ... [-R root] [-D] [-l]
  *              [-d dir | -c cachefile] [-f] -a
- *       import [-o mntopts] [-o prop=value] ... [-R root] [-D]
+ *       import [-o mntopts] [-o prop=value] ... [-R root] [-D] [-l]
  *              [-d dir | -c cachefile] [-f] [-n] [-F] <pool | id> [newpool]
  *
  *	 -c	Read pool information from a cachefile instead of searching
@@ -2393,6 +2405,8 @@ do_import(nvlist_t *config, const char *newname, const char *mntopts,
  *
  *       -a	Import all pools found.
  *
+ *       -l	Load encryption keys while importing.
+ *
  *       -o	Set property=value and/or temporary mount options (without '=').
  *
  *	 -s	Scan using the default search path, the libblkid cache will
@@ -2434,7 +2448,7 @@ zpool_do_import(int argc, char **argv)
 	char *endptr;
 
 	/* check options */
-	while ((c = getopt(argc, argv, ":aCc:d:DEfFmnNo:R:stT:VX")) != -1) {
+	while ((c = getopt(argc, argv, ":aCc:d:DEfFlmnNo:R:stT:VX")) != -1) {
 		switch (c) {
 		case 'a':
 			do_all = B_TRUE;
@@ -2464,6 +2478,9 @@ zpool_do_import(int argc, char **argv)
 		case 'F':
 			do_rewind = B_TRUE;
 			break;
+		case 'l':
+			flags |= ZFS_IMPORT_LOAD_KEYS;
+			break;
 		case 'm':
 			flags |= ZFS_IMPORT_MISSING_LOG;
 			break;
@@ -2538,6 +2555,17 @@ zpool_do_import(int argc, char **argv)
 		usage(B_FALSE);
 	}
 
+	if ((flags & ZFS_IMPORT_LOAD_KEYS) && (flags & ZFS_IMPORT_ONLY)) {
+		(void) fprintf(stderr, gettext("-l is incompatible with -N\n"));
+		usage(B_FALSE);
+	}
+
+	if ((flags & ZFS_IMPORT_LOAD_KEYS) && !do_all && argc == 0) {
+		(void) fprintf(stderr, gettext("-l is only meaningful during "
+		    "an import\n"));
+		usage(B_FALSE);
+	}
+
 	if ((dryrun || xtreme_rewind) && !do_rewind) {
 		(void) fprintf(stderr,
 		    gettext("-n or -X only meaningful with -F\n"));
@@ -5370,6 +5398,7 @@ zpool_do_detach(int argc, char **argv)
  *	-o	Set property=value, or set mount options.
  *	-P	Display full path for vdev name.
  *	-R	Mount the split-off pool under an alternate root.
+ *	-l	Load encryption keys while importing.
  *
  * Splits the named pool and gives it the new pool name.  Devices to be split
  * off may be listed, provided that no more than one device is specified
@@ -5387,6 +5416,7 @@ zpool_do_split(int argc, char **argv)
 	char *mntopts = NULL;
 	splitflags_t flags;
 	int c, ret = 0;
+	boolean_t loadkeys = B_FALSE;
 	zpool_handle_t *zhp;
 	nvlist_t *config, *props = NULL;
 
@@ -5395,7 +5425,7 @@ zpool_do_split(int argc, char **argv)
 	flags.name_flags = 0;
 
 	/* check options */
-	while ((c = getopt(argc, argv, ":gLR:no:P")) != -1) {
+	while ((c = getopt(argc, argv, ":gLR:lno:P")) != -1) {
 		switch (c) {
 		case 'g':
 			flags.name_flags |= VDEV_NAME_GUID;
@@ -5412,6 +5442,9 @@ zpool_do_split(int argc, char **argv)
 				usage(B_FALSE);
 			}
 			break;
+		case 'l':
+			loadkeys = B_TRUE;
+			break;
 		case 'n':
 			flags.dryrun = B_TRUE;
 			break;
@@ -5450,6 +5483,12 @@ zpool_do_split(int argc, char **argv)
 		usage(B_FALSE);
 	}
 
+	if (!flags.import && loadkeys) {
+		(void) fprintf(stderr, gettext("loading keys is only "
+		    "valid when importing the pool\n"));
+		usage(B_FALSE);
+	}
+
 	argc -= optind;
 	argv += optind;
 
@@ -5502,6 +5541,13 @@ zpool_do_split(int argc, char **argv)
 		nvlist_free(props);
 		return (1);
 	}
+
+	if (loadkeys) {
+		ret = zfs_crypto_attempt_load_keys(g_zfs, newpool);
+		if (ret != 0)
+			ret = 1;
+	}
+
 	if (zpool_get_state(zhp) != POOL_STATE_UNAVAIL &&
 	    zpool_enable_datasets(zhp, mntopts, 0) != 0) {
 		ret = 1;