Where to hook my custom access control module?

Hello,

first of all, I've tried to ask on pgsql-general mailing list as advised, 
but no answer.

I'd like to look at a possibility of integrating OpenPMF 
(http://www.openpmf.org) with the PostgreSQL. There is a possibility to 
have a "weak" integration by using a provided rule system and SQL, but 
this way we would lose central management functionality of OpenPMF, 
especially its policy violation notifications and we'll need to 
synchronize rules with policies from time to time. So now I think about 
how to directly integrate some kind of OpenPMF policy enforcement point 
into the PostgreSQL. For this I would need some access control hook inside 
PostgreSQL which would be called on every action and my PEP would get a 
chance to deny some access. Is there anything like that supported in the 
PostgreSQL?

Thanks!
Karel
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Karel Gardas                  kgardas@objectsecurity.com
ObjectSecurity Ltd.           http://www.objectsecurity.com