wget -O ipk.pub https://master.dl.sourceforge.net/project/openwrt-passwall-build/ipk.pub
opkg-key add ipk.pub
read release arch << EOF
$(. /etc/openwrt_release ; echo ${DISTRIB_RELEASE%.*} $DISTRIB_ARCH)
EOF
for feed in passwall_luci passwall_packages passwall2; do
echo "src/gz $feed https://master.dl.sourceforge.net/project/openwrt-passwall-build/releases/packages-$release/$arch/$feed" >> /etc/opkg/customfeeds.conf
done
opkg update
#Then update the package in web for luci-pa..
Reference link.