Recover your data from a LUKS encrypted disk
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9 years ago 5 |
The other day I messed up my system, and needed to find a way to recover my data on the drive. I had encrypted the drive during install, as well as encrypted my Home drive. This tutorial will show you how to recover from both using a live CD. This is only to recover your data, in the end I reinstalled the OS after I got the data I needed.
To recover the whole disk
LM uses LUKS for the disk encryption as of the writing of this tutorial.
Step 1, Boot up the machine you want to recover data from with a live CD or USB, this of course assumes that the physical hardware is still working.
Step 2, open system settings and then users and groups create a user that has admin priveledge, preferably the same user name as was on the system before it went down.
Step 3, log off , then log on as your new user. DO NOT SHUT DOWN You will have to start over if you do.
Step 4, open a terminal and type:
sudo su , enter your password.
WARNING: This will put you in super user mode and allow you to run all the following commands, it will also allow you to do bad things to your system so use carefully. If you do not want to do this, put sudo in front of each command.
Step 5, in the same terminal type:
cat /proc/partitions/
This will give you output similar to this:
# cat /proc/partitions
major minor #blocks name
1 0 65536 ram0
1 1 65536 ram1
1 2 65536 ram2
1 3 65536 ram3
1 4 65536 ram4
1 5 65536 ram5
1 6 65536 ram6
1 7 65536 ram7
1 8 65536 ram8
1 9 65536 ram9
1 10 65536 ram10
1 11 65536 ram11
1 12 65536 ram12
1 13 65536 ram13
1 14 65536 ram14
1 15 65536 ram15
8 0 244198584 sda
8 1 248832 sda1
8 2 1 sda2
8 5 243947520 sda5
11 0 1048575 sr0
252 0 239894528 dm-0
252 1 4046848 dm-1
11 1 1048575 sr1
What you will be looking for is what is highlighted, in my case I only had one disk, so mine was sda.
Step 6, in the terminal again type:
fdisk -l /dev/sda/
Your output should be like this
Disk /dev/sda: 250.1 GB, 250059350016 bytes
255 heads, 63 sectors/track, 30401 cylinders, total 488397168 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: 0x000bfee0
Device Boot Start End Blocks Id System
/dev/sda1 * 2048 499711 248832 83 Linux
/dev/sda2 501758 488396799 243947521 5 Extended
/dev/sda5 501760 488396799 243947520 8e Linux LVM
Step 7, determine which partion is encrypted, I have three partions on this disk, so I will run the command three times, you may not have as many partitions. In the terminal type:
cryptsetup -v luksDump /dev/sda# -- # is the number of each partition, in my case 1, 2, 5
If the partition is not encrypted your output will look like this:
Device /dev/sda# is not a valid LUKS device. --# is the number of the partition you used
Command failed with code 22: Device /dev/sda1 is not a valid LUKS device.
If the partition is encrypted the output should look like this:
LUKS header information for /dev/sda5
Version: 1
Cipher name: aes
Cipher mode: xts-plain64
Hash spec: sha1
Payload offset: 4096
MK bits: 512
MK digest: 21 84 3e c0 3e 9e 23 1e 34 9b 39 05 8f b9 47 61 89 a6 2a 81
MK salt: fc ac 3d 4f 1e 3d d4 ce 66 6b d3 90 ba f4 79 a8
d9 c9 38 a0 c2 79 bc 47 71 c6 8f 49 23 46 f1 6b
MK iterations: 22500
UUID: 2c8d56ec-749f-4d95-ab39-4ea17edb4c01
Key Slot 0: ENABLED
Iterations: 90067
Salt: e4 25 ae 7c 5d 62 81 5e ea 37 95 0f 59 7b c8 7f
13 4f bc 15 70 4e 82 e1 41 db 1d 4b 65 7a de 5c
Key material offset: 8
AF stripes: 4000
Key Slot 1: DISABLED
Key Slot 2: DISABLED
Key Slot 3: DISABLED
Key Slot 4: DISABLED
Key Slot 5: DISABLED
Key Slot 6: DISABLED
Key Slot 7: DISABLED
Command successful.
Step 8, Now that you know which partition to work with you can un-encrypt it.
WARNING - you need to know the pass-phrase that was used when the disk was encrypted if you do not know this, then you are out of luck. that is of course why it was encrypted in the first place.
In the terminal type:
cryptsetup -v luksOpen /dev/sda#/ sda#_crypt -- # is the number of the partition
You will need to enter the pass-phrase, and if successful it will output this:
Key slot 0 unlocked.
Command successful
Step 9, LVM (Logical Volume Management) you will need to see if your data is on a volume so you know which one to mount. in the terminal type:
lvdisplay
If this is being used you will see something like this:
--- Logical volume ---
LV Path /dev/mint-vg/root
LV Name root
VG Name mint-vg
LV UUID C4po3E-t1oZ-cAD4-I8WM-ZbWA-mbPC-n3gYKN
LV Write Access read/write
LV Creation host, time mint, 2015-08-24 18:35:41 -0700
LV Status available
# open 1
LV Size 228.78 GiB
Current LE 58568
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 256
Block device 252:0
--- Logical volume ---
LV Path /dev/mint-vg/swap_1
LV Name swap_1
VG Name mint-vg
LV UUID 4dOwi6-XW2t-BFZa-68Or-Kjeg-jMi6-Wl7fGp
LV Write Access read/write
LV Creation host, time mint, 2015-08-24 18:35:42 -0700
LV Status available
# open 2
LV Size 3.86 GiB
Current LE 988
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 256
Block device 252:1
You want the VG name, in my case it is mint-vg
Step 10, Enable the volume groups, in the terminal type:
vgchange -a y mint-vg
your output should be like this:
2 logical volume(s) in volume group "mint-vg" now active
Step 11, mount the /dev/mint-vg/root volume, byt typing this in the terminal:
mkdir /tmp/disk
mount /dev/mint-vg/root/ /tmp/disk
Step 12, browse to /tmp/disk and view or move your data etc.
WARNING - if you also encrypted your home directory, there is one more step
Step 12a, if you have encrypted your Home directory and you need access to those files as well, then this is why I had you create a user of the same name and password as the original user. In the terminal type:
ecryptfs-recover-private --rw
This will check the whole machine for an encrypted directory, if it finds one you will be asked for the pass-phrase for it.
You can read more about this at:
manpages.ubuntu.com/manpages/vivid/en/man1/ecryptfs-recover-private.1.html
Once you finish you can unmount the partiton and close the encryption back, by using these command in the terminal:
umount /tmp/disk
cryptsetup luksClose /dev/mapper/sda5_crypt
I just restarted the machine and did not worry about this because I was going to re-image the machine again any way.
Comments
Thanks cbertram. We just finished following this guide in #linuxmint-help for a user who had upgrade to 17.2 which caused him to get locked out of his system.