[SR-Users] Kamailio reading an external configuration file from the main config.

Is there any way that i can create a list of ips for kamailio to compare and do something, for example create an authorize list of ips on txt that it can read for each invite that i receive than check a variable against that list. for example do a search $si on the external text file and if match do something if it doesn't then continue the route downwards. I am trying to create a list of banned ips but don't want to do it on the firewall since i want to log all the bad ips and added to the list and do something every time i receive a packed from any of the ips on the list. is that possible with kamailio , is there any module i can use to cook this configuration ? Thank you Julian