File debian.postinst of Package efitools
#!/bin/bash
if efitool-installkeys --install --sign; then
:;
else
echo "Could not find your secure USB stick with the keys"
echo
echo "If you haven't created one yet, please use efitool-genkeys"
echo "If you have created one, please insert it and run"
echo " efitool-updatekeys --install --sign"
fi
exit 0;