Alex,
> As such, I would like to see some documentation about securing the
> database at a data and application level. It would be nice to have some
> general guidelines, as well as being able to cite documentation when
> setting up a security policy for a database application.
I'd be happy to participate in discussing security strategies for PostgreSQL
databases; I do a bit of this for my clients though, not, I think, on the
level of need you face. A lot can be done especially with 7.4 by
manipulating permissions, obfuscating database objects through views,
functions, and rules, and otherwise "locking down" database objects. For
example, if the web server user's only access to a table is via a
set-returing search function, and that user has no other permissions, a SQL
injection attack isn't going to obtain anything other than an error.
The problem with this approach, of course, is that large application
developers generally like to make the database fairly "passive" and put all
business & security logic in the middleware. I do think it would be useful
for them to realize that they are sacrificing a significant portion of their
data security by doing so.
On a machine/network level, all I really do is lock down port access to the
database server, and make sure that the db server has no ports that point to
unsecured networks (as well as the usual user/database/password
restrictions). My general perspective is that if an attacker can gain
unrestricted port access to the database, a break-in is only a matter of time
-- if through nothing else than password-guessing attacks.
I'm not sure such a paper is appropriate for the main docs. But it is
definitely appropriate for TechDocs.
--
Josh Berkus
Aglio Database Solutions
San Francisco