Hi all, I would like to insert a check on users' MAC address operated by freeRADIUS. The objective is to allow users to use only one MAC address to gain access to a Wi-Fi network. The new query will check if user's MAC address is the same of his first access, and deny access if he is using a different one. To do this a new query needs to be inserted into /raddb/sql.conf to perform this check in the authentication process, and the src/modules/rlm_sql/rlm_sql.c needs to be modified. Writing the new query is not a problem, but modifying rlm_sql.c seems to be not so easy. Could somebody give indication on how to do this in order to speed up development process? A description of information flow (variables/funtions/pointers) into rlm_sql.c might be useful. Thank you in advance, Best regards, Carlo