新增 LUKS 的 keyfiles

1. 在 xfs, ext4 及 vfat 三個 lv 掛載目錄下，各新增一把金鑰。

   [root@kvm7 ~]# dd if=/dev/urandom of=/mnt/lukskey/xfs/xfskeyfile bs=1024 count=4
   4+0 records in
   4+0 records out
   4096 bytes (4.1 kB) copied, 0.000942181 s, 4.3 MB/s
   [root@kvm7 ~]# dd if=/dev/urandom of=/mnt/lukskey/ext4/ext4keyfile bs=1024 count=4
   4+0 records in
   4+0 records out
   4096 bytes (4.1 kB) copied, 0.000761101 s, 5.4 MB/s
   [root@kvm7 ~]# dd if=/dev/urandom of=/mnt/lukskey/vfat/vfatkeyfile bs=1024 count=4
   4+0 records in
   4+0 records out
   4096 bytes (4.1 kB) copied, 0.00172373 s, 2.4 MB/s
   

2. 將 xfs, ext4 及 vfat 三個 lv 掛載目錄下的金鑰，都新增為開啟 /dev/vdb1 的金鑰。

   [root@kvm7 ~]# cryptsetup luksAddKey /dev/vdb1 /mnt/lukskey/xfs/xfskeyfile 
   Enter any existing passphrase: 
   [root@kvm7 ~]# cryptsetup luksAddKey /dev/vdb1 /mnt/lukskey/ext4/ext4keyfile 
   Enter any existing passphrase: 
   [root@kvm7 ~]# cryptsetup luksAddKey /dev/vdb1 /mnt/lukskey/vfat/vfatkeyfile 
   Enter any existing passphrase:
   

3. 查看 /dev/vdb1 的金鑰，目前有 Key Slot 0 至 4 共 5 把金鑰。

   [root@kvm7 ~]# cryptsetup luksDump /dev/vdb1
   LUKS header information for /dev/vdb1
   
   Version:		1
   Cipher name:	aes
   Cipher mode:	xts-plain64
   Hash spec:		sha256
   Payload offset:	4096
   MK bits:		256
   MK digest:		dc f8 00 ba 18 9d ee 80 80 27 c9 5e 2b e4 88 5e e0 05 d6 39 
   MK salt:		d1 3e 91 cb 80 f3 4f 9d 91 c4 da e2 25 e2 5b 5e 
   				78 d5 07 de 04 6e fd 9e 48 4d 8a 31 49 42 16 f5 
   MK iterations:	35008
   UUID:			77472cc9-0dd3-4c4c-81ad-e0ecae7570b2
   
   Key Slot 0: ENABLED
   	Iterations:				556568
   	Salt:					6f ea 6a 2c c8 4b 97 d2 47 c9 6b c8 ef b2 d7 86 
   							a6 58 41 14 8f 34 3f a9 d4 25 02 6c 0e c8 a6 12 
   	Key material offset:	8
   	AF stripes:				4000
   Key Slot 1: ENABLED
   	Iterations:				563144
   	Salt:					66 0e 2e c1 8a a3 3f cb 21 7d 50 ed aa 96 3d d7 
   							09 54 36 a9 15 5a b1 3e 4e fe 35 d6 10 b3 ac 35 
   	Key material offset:	264
   	AF stripes:				4000
   Key Slot 2: ENABLED
   	Iterations:				517558
   	Salt:					59 ef 20 e6 1b da 6e b9 03 0f c4 8c 4d 1a 57 71 
   							5d 18 92 e8 da 42 b9 9b 00 0f f2 17 ee e1 10 41 
   	Key material offset:	520
   	AF stripes:				4000
   Key Slot 3: ENABLED
   	Iterations:				539946
   	Salt:					8b 0e d0 09 ad 19 77 51 a6 5c 61 24 37 24 a6 02 
   							f2 95 02 6e 36 52 52 fb 2a 24 66 56 ad 54 2f fd 
   	Key material offset:	776
   	AF stripes:				4000
   Key Slot 4: ENABLED
   	Iterations:				520642
   	Salt:					7f 34 1c 22 4d 97 1d 9f d2 fe fb 8b 4c 47 42 de 
   							b0 a5 6d 82 54 0e 26 65 f5 4f ac 9e 9e 8a 01 33 
   	Key material offset:	1032
   	AF stripes:				4000
   Key Slot 5: DISABLED
   Key Slot 6: DISABLED
   Key Slot 7: DISABLED