upgradeOpenWrtRelease

#!/usr/bin/env ash
RELEASE=$(wget -qO- https://downloads.openwrt.org/.versions.json | awk -F '"' '/"stable_version"/{print $4}')
MODEL=$(cat /tmp/sysinfo/model)

case "$MODEL" in
  'Zyxel NWA50AX Pro')
    export SYSUPGRADE_IMAGE_NAME="openwrt-${RELEASE}-mediatek-filogic-zyxel_nwa50ax-pro-squashfs-sysupgrade.bin"
    export TARGET_PREFIX="mediatek/filogic"
  ;;
  'XikeStor SKS8300-8X')
    export SYSUPGRADE_IMAGE_NAME="openwrt-${RELEASE}-realtek-rtl930x-xikestor_sks8300-8x-squashfs-sysupgrade.bin"
    export TARGET_PREFIX="realtek/rtl930x"
  ;;
  'AVM FRITZ!Box 7530')
    export SYSUPGRADE_IMAGE_NAME="openwrt-${RELEASE}-ipq40xx-generic-avm_fritzbox-7530-squashfs-sysupgrade.bin"
    export TARGET_PREFIX="ipq40xx/generic"
  ;;
  *)
    echo "${MODEL} is currently unsupported"
    exit 1
  ;;
esac

export SYSUPGRADE_IMAGE_URL="https://downloads.openwrt.org/releases/${RELEASE}/targets/${TARGET_PREFIX}/${SYSUPGRADE_IMAGE_NAME}"
export CHECKSUMS_URL="https://downloads.openwrt.org/releases/${RELEASE}/targets/${TARGET_PREFIX}/sha256sums"
cd /tmp
wget "${SYSUPGRADE_IMAGE_URL}"
wget -qO- "${CHECKSUMS_URL}" | grep "${SYSUPGRADE_IMAGE_NAME}" | tr -d '*' > sha256sum_filtered
if sha256sum -c sha256sum_filtered; then
  echo "Hash Check Successful!"
  echo "Starting Sysupgrade:"
  echo ""
  sysupgrade -v "${SYSUPGRADE_IMAGE_NAME}"
fi