On 8/9/07, Andrew Dunstan <andrew@dunslane.net> wrote:
> Decibel! wrote:
> > This is also related to the desire to be able to restrict access to the
> > catalog tables. Doing so could potentially solve this problem; it
> > solves other issues (such as being able to see all the databases that
> > exist on a server, something that hosting environments care about).>
>
> You can hide the catalogs, albeit at the cost of some functionality. I
> did some experimentation a couple of years back with removing public
> access from the catalogs, removing information_schema and the public
> schema, etc, and it worked quite well. I set up a user who had access to
> a single schema, which only contained functions, and the user wasn't
> able (so far as I could determine) to see anything other than those
> functions - no tables, no catalogs, no databases, no users. The user was
> still able to function exactly as intended. The intended scenario was
> for a web app user, where the web server was subverted, the aim being to
> restrict the amount of information the intruder could steal.
This works very well to stop casual browsing of functions from psql, etc.
That said, I am in the camp that securing system catalogs (including
pg_proc) is a good and necessary feature. This debate came up a while
back with all the usual arguments pro- and con-. IIRC the general
conclusion was that if you want to truly encrypt the sources for your
functions, the basic idea is to create a new stored procedure language
that wraps pl/pgsql and handles encryption there.
This would be relatively easy to support as an external module, I think.
merlin
