设备/dev/sda3 3不是有效的LUKS设备

Question

我已经根据文档创建了一个LUKS加密分区。但是在重新启动之后，我就不能再访问驱动器了。错误消息非常简短：

Device /dev/sda3 is not a valid LUKS device.

当然，我试图搜索它，并尝试了一些恢复尝试，但是当我查看设备时，我得到了一些在我看来是有效的LUKS标题：

# dd if=/dev/sda3 count=128 | hd
2+0 records in
2+0 records out
1024 bytes (1.0 kB, 1.0 KiB) copied, 0.00133979 s, 764 kB/s
00000000  4c 55 4b 53 ba be 00 02  00 00 00 00 00 00 40 00  |LUKS..........@.|
00000010  00 00 00 00 00 00 00 04  00 00 00 00 00 00 00 00  |................|
00000020  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00000040  00 00 00 00 00 00 00 00  73 68 61 32 35 36 00 00  |........sha256..|
00000050  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
00000060  00 00 00 00 00 00 00 00  fb 4b 9c 76 5f 0f ac 65  |.........K.v_..e|
00000070  8b 78 3e 7f 32 8e c3 ea  b9 fb 43 83 92 41 64 9e  |.x>.2.....C..Ad.|
00000080  14 83 eb 3c 65 09 2a 31  36 c1 c1 36 16 62 c8 f7  |...<e.*16..6.b..|
00000090  ce 43 bc 41 ad 3e 3f 74  18 4c 09 78 98 96 c6 0e  |.C.A.>?t.L.x....|
000000a0  60 19 e1 fe 5e db 64 ce  64 66 32 66 35 61 62 63  |`...^.d.df2f5abc|
000000b0  2d 37 38 66 33 2d 34 66  34 38 2d 39 33 62 30 2d  |-78f3-4f48-93b0-|
000000c0  35 32 63 35 37 38 34 34  34 30 61 37 00 00 00 00  |52c5784440a7....|
000000d0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
000001c0  3d e5 70 f7 eb ac 1f cf  f9 0b d4 a9 83 17 e9 38  |=.p............8|
000001d0  08 0b e5 3f 8d 5b 52 dc  87 1f d2 f4 4f 2a 27 d1  |...?.[R.....O*'.|
000001e0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|

唯一明显错误的是，我错误地创建了分区：

# fdisk -l /dev/sda
Ignoring extra data in partition table 5.
Invalid flag 0x0000 of EBR (for partition 5) will be corrected by w(rite).
Disk /dev/sda: 400 GiB, 429496729600 bytes, 838860800 sectors
Disk model: QEMU HARDDISK   
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0xc915a69a

Device     Boot     Start        End   Sectors   Size Id Type
/dev/sda1  *         2048    1953791   1951744   953M 83 Linux
/dev/sda2         1953792  419428351 417474560 199.1G 83 Linux
/dev/sda3       419428352  838860799 419432448   200G  5 Extended
/dev/sda5       620349215 1014853874 394504660 188.1G 70 DiskSecure Multi-Boot

尽管如此，我还是应该能够以某种方式访问这些数据。但是怎么做呢？

Answer 1

我解决这个问题的一种方法是通过一个回环设备安装它：

losetup -o 214747316224 /dev/loop0 /dev/sda && cryptsetup luksOpen /dev/loop0 data --key-file=...

214747316224是分区/dev/sda3 3倍于块大小(419428352*512)的开始。

所以很明显，分区表是错误的。这就留下了一个问题:如何在不丢失所有数据的情况下修复它？