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Create named LUKS encrypted volume

Terminal - Create named LUKS encrypted volume
edrv() { N=${1:-edrv}; truncate -s ${2:-256m} $N.img && L=$(losetup -f) && losetup $L $N.img && cryptsetup luksFormat --batch-mode $L && cryptsetup luksOpen $L $N && mkfs.vfat /dev/mapper/$N -n $N; cryptsetup luksClose $N; echo losetup -d $L to unmount; }
2014-02-24 01:38:21
User: snipertyler
Functions: echo losetup
2
Create named LUKS encrypted volume

You need to be root to do this. So check the command before running it.

You enter the same password for

Enter LUKS passphrase:

Verify passphrase:

Enter passphrase for /dev/loopn:

___

You can then copy the .img file to somewhere else.

Loop it it with losetup -f IMAGENAME.img and then mount it with a file manager (eg nemo) or run mount /dev/loopn /media/mountfolder

Acts similar to a mounted flash drive

Alternatives

There are 2 alternatives - vote for the best!

Terminal - Alternatives

Know a better way?

If you can do better, submit your command here.

What others think

Interesting.

A few things I'd improve on.

You use dd to create a sparse file, but truncate would be better:

Besides, your file is 256MiB + 1 byte long. Urgh!

truncate -s 256m

If you're likely to fill the container, then a better bet would be fallocate.

ext4 and btrfs support fallocate which will near-instantly allocate a contiguous block of space.

fallocate -l 256m

Next, I'd add a second parameter to control the size. This is very simple to do, using a defaulting variable

${2:-256}

If $2 exists use it, otherwise use the number 256, e.g.

fallocate -l ${2:-256}m $1

Unless Luks is supported by Windows (I haven't checked, but I'd be surprised if it were),

I'd put a REAL filesystem inside the container:

mke2fs -t ext4

Finally, I'd do something about the passwords. I don't want to type them in three times.

A quick idea might be to turn on cryptsetup's batch mode

cryptsetup luksFormat --batch-mode
Comment by flatcap 21 weeks and 2 days ago

I liked a lot of what you suggested & changed it.

For the purposes of combatibility (there is a third party windows program that can open luks I believe) I left it FAT. In *nix only, I would do that (and personally will)

Comment by snipertyler 21 weeks and 1 day ago

:-)

Comment by flatcap 21 weeks and 1 day ago

Your point of view

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