Nocid inbound rule

Hi to all. I’ve searched here and there, unfortunately I’ve found no answer.
I’ve freepbx based on raspberry. What I need to do is forward all calls with no cid info to an extension.
I’ve tried to play with some setting in the inbound route module without luck. I think the telco is not passing me the info “Private, Anonymous, etc…” but is simply not passing the CID or a “null” cid. So how can I discriminate between match all cids and no cid as leaving the box empty matches both?
Thanks for reading :smile:
Regards, Gianluca