zdb: add ZFS_KEYFORMAT_RAW support for -K option

This change adds support for ZFS_KEYFORMAT_RAW to zdb_derive_key in 
zdb.c. The implementation reads the raw key from the file specified 
by the -K option which is consistent with how raw keys are handled in 
the other parts of ZFS, along with a check to ensure that the keyfile 
doesn't have too many bytes.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Patrick Xia <patrickx@google.com>
Closes #17783

cmd/zdb/zdb.c

@@ -3301,6 +3301,7 @@ zdb_derive_key(dsl_dir_t *dd, uint8_t *key_out)
 	uint64_t keyformat, salt, iters;
 	int i;
 	unsigned char c;
+	FILE *f;
 
 	VERIFY0(zap_lookup(dd->dd_pool->dp_meta_objset, dd->dd_crypto_obj,
 	    zfs_prop_to_name(ZFS_PROP_KEYFORMAT), sizeof (uint64_t),
@@ -3333,6 +3334,25 @@ zdb_derive_key(dsl_dir_t *dd, uint8_t *key_out)
 
 		break;
 
+	case ZFS_KEYFORMAT_RAW:
+		if ((f = fopen(key_material, "r")) == NULL)
+			return (B_FALSE);
+
+		if (fread(key_out, 1, WRAPPING_KEY_LEN, f) !=
+		    WRAPPING_KEY_LEN) {
+			(void) fclose(f);
+			return (B_FALSE);
+		}
+
+		/* Check the key length */
+		if (fgetc(f) != EOF) {
+			(void) fclose(f);
+			return (B_FALSE);
+		}
+
+		(void) fclose(f);
+		break;
+
 	default:
 		fatal("no support for key format %u\n",
 		    (unsigned int) keyformat);

tests/runfiles/common.run

@@ -168,10 +168,10 @@ tags = ['functional', 'cli_root', 'zinject']
 tests = ['zdb_002_pos', 'zdb_003_pos', 'zdb_004_pos', 'zdb_005_pos',
     'zdb_006_pos', 'zdb_args_neg', 'zdb_args_pos',
     'zdb_block_size_histogram', 'zdb_checksum', 'zdb_decompress',
-    'zdb_display_block', 'zdb_encrypted', 'zdb_label_checksum',
-    'zdb_object_range_neg', 'zdb_object_range_pos', 'zdb_objset_id',
-    'zdb_decompress_zstd', 'zdb_recover', 'zdb_recover_2', 'zdb_backup',
-    'zdb_tunables']
+    'zdb_display_block', 'zdb_encrypted', 'zdb_encrypted_raw',
+    'zdb_label_checksum', 'zdb_object_range_neg', 'zdb_object_range_pos',
+    'zdb_objset_id', 'zdb_decompress_zstd', 'zdb_recover', 'zdb_recover_2',
+    'zdb_backup', 'zdb_tunables']
 pre =
 post =
 tags = ['functional', 'cli_root', 'zdb']

tests/zfs-tests/tests/Makefile.am

@@ -640,6 +640,7 @@ nobase_dist_datadir_zfs_tests_tests_SCRIPTS += \
 	functional/cli_root/zdb/zdb_decompress_zstd.ksh \
 	functional/cli_root/zdb/zdb_display_block.ksh \
 	functional/cli_root/zdb/zdb_encrypted.ksh \
+	functional/cli_root/zdb/zdb_encrypted_raw.ksh \
 	functional/cli_root/zdb/zdb_label_checksum.ksh \
 	functional/cli_root/zdb/zdb_object_range_neg.ksh \
 	functional/cli_root/zdb/zdb_object_range_pos.ksh \

tests/zfs-tests/tests/functional/cli_root/zdb/zdb_encrypted_raw.ksh

@@ -0,0 +1,75 @@
+#!/bin/ksh -p
+# SPDX-License-Identifier: CDDL-1.0
+#
+# 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) 2023, Klara Inc.
+#
+
+. $STF_SUITE/include/libtest.shlib
+. $STF_SUITE/tests/functional/cli_root/zfs_load-key/zfs_load-key_common.kshlib
+
+#
+# DESCRIPTION:
+# 'zdb -K ...' should enable reading from a raw-encrypted dataset
+#
+# STRATEGY:
+# 1. Create an encrypted dataset
+# 2. Write some data to a file
+# 3. Run zdb -dddd on the file, confirm it can't be read
+# 4. Run zdb -K ... -ddddd on the file, confirm it can be read
+#
+
+verify_runnable "both"
+
+dataset="$TESTPOOL/$TESTFS2"
+file="$TESTDIR2/somefile"
+keyfile="$TEST_BASE_DIR/keyfile"
+
+function cleanup
+{
+	datasetexists "$dataset" && destroy_dataset "$dataset" -f
+	rm -f "$keyfile"
+	default_cleanup_noexit
+}
+
+log_onexit cleanup
+
+log_must default_setup_noexit $DISKS
+
+log_assert "'zdb -K' should enable reading from a raw-encrypted dataset"
+
+# The key must be 32 bytes long.
+echo -n "$RAWKEY" > "$keyfile"
+
+log_must zfs create -o mountpoint="$TESTDIR2" \
+    -o encryption=on -o keyformat=raw -o keylocation="file://$keyfile" \
+    "$dataset"
+
+echo 'my great encrypted text' > "$file"
+
+typeset -i obj=$(ls -i "$file" | cut -d' ' -f1)
+typeset -i size=$(wc -c < "$file")
+
+log_note "test file $file is objid $obj, size $size"
+
+sync_pool "$TESTPOOL" true
+
+log_must eval "zdb -dddd $dataset $obj | grep -q 'object encrypted'"
+
+log_must eval "zdb -K $keyfile -dddd $dataset $obj | grep -q 'size\s$size$'"
+
+log_pass "'zdb -K' enables reading from a raw-encrypted dataset"