Usb drive encryption

[Fitz Mutch]

https://github.com/RMerl/asuswrt-merlin/wiki/LUKS-Encrypted-USB-Drive-HOWTO

That is a very good wiki on how to do encryption with dm-crypt and LUKS.

Next, it's possible to mount a Veracrypt or Truecrypt encrypted device on the router? Yes. This requires a backport from Linux 2.6.38.8 to Asuswrt-Merlin for the algif_skcipher kernel module. And the cryptsetup program must be compiled without "--disable-kernel_crypto".

How to apply the patch

cd ~/asuswrt-merlin
patch -p2 -i ~/380.66-alpha1_ARM_dm-crypt+skcipher.patch

Example: mount a Veracrypt encrypted file container on the router

# first, use Veracrypt to create an encrypted file container named "vctest.img"
# then copy it to the router and run this script
losetup /dev/loop6 ./vctest.img
modprobe algif_skcipher  # you'll need my kernel patch (see below)
cryptsetup --veracrypt tcryptOpen /dev/loop6 vctest
# now wait 5 minutes; yes, it takes a very long time
mkdir /mnt/vctest
mount /dev/mapper/vctest /mnt/vctest
# now copy some files that you want encrypted, to the /mnt/vctest folder
umount /mnt/vctest
cryptsetup tcryptClose vctest
losetup -d /dev/loop6

An encrypted file container created on Microsoft Windows using Veracrypt may now be used on the router.