Description:
I use ykfde (from https://github.com/agherzan/yubikey-full-disk-encryption ) as recommended on the Yubikey page to decrypt my luks drive. The provided hook is this package detects the key, provide the challenge, get the answer from the key and sends it to cryptsetup to open the volume.

However, when I use this hook, the encrypt hook following doesn't detect the volume has already been opened. I would like to use both hooks (since I use a keyfile on an external USB key as a backup and only the encrypt hook supports this).

The way forward to solve this issue would be either to consider the device already mounted as valid (if the names are the same), or to support the Yubikey.
The latter solution would be ideal, but I reckon it would need more work to be integrated. The former solution provide (I think) a more modular solution, since it would not prevent someone from using another hook (or even a custom hook) to unlock a volume while still allowing the encrypt hook to detect the volume is already opened.


Additional info:
* package version: 1.7.5-1


Steps to reproduce:
* Install ykfde from https://github.com/agherzan/yubikey-full-disk-encryption
* Setup the ykfde hook just before the encrypt hook in mkinitcpio.conf
* Unlock the same volume with ykfde as is setup to be unlocked by encrypt
* Watch encrypt complain about the volume existing already but not move forward with the boot :)