Re: Inserts restricted to a trigger

Thanks for the suggestion. Unfortunately we only have a single login role
(it's a web app) and then we SET ROLE according to the contents of a JSON
Web Token. So we end up with SESSION_USER as the logged in user and the
active role as CURRENT_USER.

It may be that we're just stuck with a gap and need to just try and keep
track of our mutation points, such as limit what is accessible through REST
or GraphQL, and there is no way to fundamentally lock this down in
Postgres. I was checking the mailing list to see if I'd missed anything.

On Tue, Jun 18, 2019 at 9:47 AM Torsten Förtsch <tfoertsch123(at)gmail(dot)com>
wrote:

> Have you tried session_user?
>
> create function xx() returns table (cur text, sess text)
> security definer language sql as $$
> select current_user::text, session_user::text;
> $$;
>
> Then log in as different user and:
>
> => select (xx()).*;
> cur | sess
> ----------+-------
> postgres | write
>
>
> On Tue, Jun 18, 2019 at 6:30 PM Miles Elam <miles(dot)elam(at)productops(dot)com>
> wrote:
>
>> That seems straightforward. Unfortunately I also want to know the
>> user/role that performed the operation. If I use SECURITY DEFINER, I get
>> the superuser account back from CURRENT_USER, not the actual user.
>>
>> Sorry, should have included that in the original email. How do I restrict
>> access while still retaining info about the current user/role?
>>
>>
>> On Mon, Jun 17, 2019 at 5:47 PM <raf(at)raf(dot)org> wrote:
>>
>>> Adrian Klaver wrote:
>>>
>>> > On 6/17/19 4:54 PM, Miles Elam wrote:
>>> > > Is there are way to restrict direct access to a table for inserts but
>>> > > allow a trigger on another table to perform an insert for that user?
>>> > >
>>> > > I'm trying to implement an audit table without allowing user
>>> tampering
>>> > > with the audit information.
>>> >
>>> > Would the below not work?:
>>> > CREATE the table as superuser or other privileged user
>>> > Have trigger function run as above user(use SECURITY DEFINER)
>>>
>>> and make sure not to give any other users insert/update/delete
>>> permissions on the audit table.
>>>
>>> > > Thanks in advance,
>>> > >
>>> > > Miles Elam
>>> >
>>> > --
>>> > Adrian Klaver
>>> > adrian(dot)klaver(at)aklaver(dot)com
>>>
>>>
>>>