Josh <josh@saucetel.com> wrote:
> I am looking for suggestions on how best to secure a server that
> is accessible via the internet. Even account creation for the
> database is open to the world. Does anybody have any extra changes
> they would make to postgresql.conf or OS changes they would
> suggest? Perhaps some default permissions that would be best
> revoked?
>
> The system setup is currently a Linux box running PostgreSQL 8.4
> My pg_hba.conf already limits remote connections to one database
> and one particular role.
The role can create databases but not access them? Odd.
In no particular order, these come to mind:
* Only allow SSL connections.
* Use a non-standard port, to obscure what the service is.
* Put the machine behind a firewall which only allows packets
through to the desired port.
* Make sure you *don't* run the database service as root.
* Make sure that the user which does run the database server doesn't
have access to anything more than it absolutely needs, directly or
through group membership. (In particular, sudo rights should be
carefully limited or non-existent.)
* Turn on logging of connections and disconnections. Save the logs
for a while.
* Limit permissions for the role to the bare minimum needed. You
haven't told us enough to know what the would mean, exactly; but not
having rights to create functions in untrusted languages would be a
start.
* If you can limit the IP addresses which need to connect, do so (in
the firewall and/or pg_hba.conf). Be prepared to block IP ranges
which are the source of attacks.
* Stay up-to-date on PostgreSQL minor releases and OS security
updates.
-Kevin