openssl dgst -sha256 -verify public.pem -signature /mnt/usb-update/update.sig /mnt/usb-update/update.zip > /dev/null 2>&1
if [[ $? = 0 ]]; then
(unzip -o /mnt/usb-update/update.zip -d /home/pi > /dev/null 2>&1 && printf "\tOK\n") || printf "\tExtract failure\n"
+ chmod +x start.sh
+ chmod +x update.sh
else
printf "\tSignature failure\n"
fi