Remote address authentication.
ALLOW_FROM = Comma separated list of IP addresses to allow requests from. By default all other addresses are denied access.
If a worker is invoked directly using an EJB call and no REMOTE_IP is specified in the RequestContext the IP-address is set to the String "null". In that case, to allow requests using EJB calls, null can be added to the list of allowed addresses.
When adding "null" to ALLOW_FROM not only locally running clients like the ClientCLI and AdminGUI is allowed access but also from workers that invoke the other worker directly using an EJB call. This is for instance the case for the XMLValidator which delegates the validation of the certificate to a CertValidator. If the CertValidator had a RemoteAddressAuthorizer allowing access from "null" then the XMLValidator would be able to use it. To restrict users from using the CertValidator (indirectly through the XMLValidator) an Authorizer could be configured for the XMLValidator.
Logging: This authorizer will add the remote IP address to the log field AUTHORIZED_ADDRESS.