Kenneth Downs <ken@secdat.com> writes:
> The biggest security limitation we have is actually a weakness in
> Postgres - the inability to restrict the abilities of a user with
> CREATUSER rights, they can make somebody who can do anything. For
> higher security this requires no ability for public registration of
> accounts. This would be solved if we could restrict a CREATUSER user to
> only GRANTing to roles they themselves are in.
I thought about this for awhile, but I think you are missing the reason
why it's designed the way it is. The point of CREATEROLE privilege is
to be a slightly safer form of superuser: that is, to allow the DBA to
do all his day-to-day management of user accounts without being a real
superuser who can corrupt the database arbitrarily badly. If we
restricted CREATEROLE as you suggest, then either DBAs would have to
make their CREATEROLE account a member of every role they manage, or
they'd have to run as real superusers. Either choice represents a
significant increase in the capabilities of the CREATEROLE account and
thus more chance for mistakes. So while a miscreant with CREATEROLE
can certainly avail himself of any database privilege short of
superuserness, in the intended use of the feature it is actually
possible for DBAs to operate with *fewer* privileges than they would
need to get useful work done if we adopted your suggestion.
regards, tom lane
