luci/applications/luci-app-openvpn/root/usr/share/rpcd/acl.d/luci-app-openvpn.json

{
	"luci-app-openvpn": {
		"description": "Grant access to OpenVPN configuration",
		"read": {
			"uci": [ "openvpn", "openvpn_recipes" ]
		},
		"write": {
			"cgi-io": [ "upload" ],
			"file": {
				"/etc/openvpn/*": [ "write" ]
			},
			"uci": [ "openvpn" ]
		}
	}
}