Systemd agent only_from like xinetd?

Hello there.

Is there an equivalent of only_from for systemd socket ?
I had the agent running with xinetd and with only_from = librenms-ip-here
But in a few new systemd servers I installed the agent with systemd.

I didn’t find something similar though. Anyone can telnet on 5665 and see everything.
Should I switch to xinetd or there is something similar to only_from = ?

Can you not just firewall that port off?