- `reject_unknown_client:` reject the request if the client hostname is unknown.
- `permit_mynetworks:` permit if the client address matches `$mynetworks`.
- `check_client_access maptype:mapname:` look up client name, parent domains, client address, or networks obtained by stripping octets. Reject if result is REJECT or "[45]xx text". Permit otherwise.
- `reject_maps_rbl:` reject if the client is listed under `$maps_rbl_domains`.
- `reject:` reject the request. Place this at the end of a restriction.
- `permit:` permit the request. Place this at the end of a restriction.