This package is inspired and based on https://github.com/tfheen/ykfde.
This enables you to use the yubikey as 2FA for LUKS. The Password you enter is used as challenge for the yubikey
The keyscript allows to boot the machine with either the password and the Yubikey or with a normal password from any key slot.
Initialize the Yubikey for challenge response in slot 2
ykpersonalize -2 -ochal-resp -ochal-hmac -ohmac-lt64 -oserial-api-visible
Build the package:
make builddeb
Install the package:
dpkg -i DEBUILD/yubikey-luks_0.?-1_all.deb
You can now assign the Yubikey to a slot using the tool
yubikey-luks-enroll
Note: The partition is hardcoded in yubikey-luks-enroll. You might need to change this!
Technically this is done by writing the response to your password (1st factor knowlege) created by the Yubikey (2nd factor possession) to a key slot.
Admitted - If the attacker was able to phish this response which looks like this: bd438575f4e8df965c80363f8aa6fe1debbe9ea9 it can be used as normal password.
It is possible to manage several Yubikeys and machines. You need to use privacyIDEA to maange the Yubikeys and the privacyIDEA admin client to push the Yubikey responses to the LUKS slots.
See https://github.com/privacyidea/privacyideaadm and https://github.com/privacyidea/privacyidea