[NCLUG] filtering DNS proxy ?

[Gabriel Somlo]

Hi All,

I'm looking for a DNS proxy that would match requests against some
set of rules, and either
    - forward the request to a *real* recursive DNS server, or
    - return a "fake" response based on the rule matched, or
    - drop the request on the floor, return some sort of error, etc.
depending on the target of the rule.

Something similar to an ACL or firewall ruleset for DNS requests. Rules
could be based on the IP of the requesting client, the content of the
request (e.g., which host are they trying to resolve), etc.

Does anyone know whether such an animal even exists, and, if so, where
can I find it ?

Thanks a ton,
Gabriel