mkinitcpio install hook to embed LUKS decryption keys to initramfs

decryption-keys

#!/bin.bash
# stigok 22-02-2018

KEYDIR=/etc/initcpio/keys

function help {
  cat <<EOF
This hook will embed decryption keys for the encrypted root device into
initramfs to automatically mount the root partition after a successful
decryption of the boot partition.
Expects keyfiles to reside in $KEYDIR with files named after their mount name
E.g: $KEYDIR/encrypted-boot.key
EOF
}

function build {
  # Add all available keys
  for file in $KEYDIR/*; do
    [ -e "$file" ] || continue
    add_file "$file" "/$(basename $file)" 0400
  done
}

This hook should be specified in /etc/mkinitcpio.conf in the HOOKS array. Example:

HOOKS=(base udev autodetect modconf block encrypt lvm2 resume decryption-keys filesystems fsck)

This file should reside at /etc/initcpio/install/decryption-keys