For context:
I've encrypted the swap partition with:

cryptsetup -v luksFormat /dev/${DEVICE}
cryptsetup luksOpen /dev/${DEVICE} swap

And what I want is for the user to be able to enter their password only once to decrypt their root partition which would contain a keyfile to then decrypt their swap partition.

Does anyone know if this is possible?
Just thought I'd ask to see if anyone's done this already

Links:

• Dm-crypt Unlocking - With a keyfile embedded in the initramfs
• Dm-crypt - Automated unlocking and mounting