Keep a backup of client keys

src/freedombone-app-vpn

@@ -340,6 +340,9 @@ function create_user_vpn_key {
 
     chown $username:$username $user_vpn_cert_file
 
+    # keep a backup
+    cp $user_vpn_cert_file /etc/openvpn/easy-rsa/keys/$username.ovpn
+
     #rm /etc/openvpn/easy-rsa/keys/$username.crt
     #rm /etc/openvpn/easy-rsa/keys/$username.csr
     shred -zu /etc/openvpn/easy-rsa/keys/$username.key