add protection for (on the fly) metadata generated files

by default all request  to unsigned metadatas (federation, circle, federationexport) which are generated on the fly are allowed.
you can limit that by adding below (optional) option into config_rr.php
$config['unsignedmeta_iplimits'] = array('IP1','IP2','IPn');
this option is set then  it must contain array of all allowed iPs (IPv4,IPv6) .  you might need to add ips of clients which are server as metadata signer/validator etc
Access to these metadas are allowed within web interface (ajax)

Access to service (sibgle entity) metadatas is not protected by that option as it can break external metadata validator .