[dm-crypt] Problem recovering encrypted partitions

Luis P. Mendes luislupe at gmail.com
Sat Jan 14 21:40:19 CET 2012


Hi,

Maybe you can help me on this.

My problem started when I booted my laptop with an OpenBSD CD that I
was trying to install to a SD card. OpenBSD installer didn't detect my
SD card, but went to partition my disk (/dev/sda).
I didnt' confirm any change to the partition table of my disk but the
installer changed the partition table of /dev/sda and I lost the
configuration.
As I didn't have a backup for the MBR of /dev/sda, I used testdisk
http://www.cgsecurity.org/ and recovered the structure of the disk.

Right now, fdisk reports:
# fdisk -l /dev/sda

Disk /dev/sda: 320.1 GB, 320072933376 bytes
255 heads, 63 sectors/track, 38913 cylinders, total 625142448 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x4483617d

Device Boot Start End Blocks Id System
/dev/sda1 63 16064 8001 83 Linux
/dev/sda2 * 81915435 112631714 15358140 83 Linux
/dev/sda3 112631715 259080254 73224270 f W95 Ext'd (LBA)
/dev/sda5 112631778 115700129 1534176 82 Linux swap
/dev/sda6 115700193 115716194 8001 83 Linux
/dev/sda7 259064253 259080254 8001 83 Linux

and cfdisk reports:
cfdisk (util-linux 2.19)

Disk Drive: /dev/sda
Size: 320072933376 bytes, 320.0 GB
Heads: 255 Sectors per Track: 63 Cylinders: 38913

Name Flags Part Type FS Type [Label] Size (MB)
--------------------------------------------------------------------------
sda1 Primary crypto_LUKS 8.23
Primary Free Space 41932.48
sda2 Boot Primary ext3 15726.74
sda5 Logical Linux swap 1571.03
sda6 Logical crypto_LUKS 8.23
Logical Free Space 73394.18
sda7 Logical crypto_LUKS 8.23
Pri/Log Free Space 187423.85*


I can boot the machine (/dev/sda2) but the encrypted partitions are
not available: /home (/dev/sda6), /opt (/dev/sda7) and /mnt/cr1
(/dev/sda1).

As you can see, for each of the three encrypted partitions, testdisk
recovered the partition as having only circa 8MB and left the rest of
the original partition as 'Free Space'.

What can I do to have each one of these partitions consider all the
'Free Space" next to them as belonging to them?

As a note, I did a 'dd' of the whole disk before using testdisk to a file.

Luis


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