How to Configure DD-WRT to use pfsense as the remote captive portal server.

[AmeyNhavelkar]

I am new to pfsense and require help in setting up a captive portal server for varrious locations in my city.
Is it possible to configure single instance of pfsense to host varrious captive portal sites .? And how can I setup a straight link between the DD-WRT and the pfsense server for captive portal authentication and after successful connection use the  internet connected to the DD-WRT.
In my setup, pfsense server is located in my home and the DD-WRT Wi-Fi routers are on the remote location.