Re: [v9.4] row level security

On Wed, Sep 4, 2013 at 10:50 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Robert Haas <robertmhaas(at)gmail(dot)com> writes:
>> On Wed, Sep 4, 2013 at 10:45 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>>> Well, the security-barrier view stuff did not present itself as a 100%
>>> solution. But perhaps more to the point, it was conceptually simple to
>>> implement, ie don't flatten views if they have this bit set, and don't
>>> push down quals into such sub-selects unless they're marked leakproof.
>
>> Right. IMHO, this new feature should be similarly simple: when an
>> unprivileged user references a table, treat that as a reference to a
>> leakproof view over the table, with the RLS qual injected into the
>> view.
>
> And for insert/update/delete, we do what exactly?

The same mechanism will prevent UPDATE and DELETE from seeing any rows
the user shouldn't be able to touch.

Simon and Greg are arguing that when an INSERT or UPDATE happens, we
ought to also check that the NEW row matches the RLS qual. I don't
find that to be terribly important because you can accomplish the same
thing with a per-row trigger today; and I also don't think everyone
will want that behavior. Some people will, I'm pretty sure, want to
let users "give away" rows, either unconditionally or subject to
defined restrictions. Perhaps it's worth having, but it's a separate
feature, IMHO.

--
Robert Haas
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