Re: postgres_fdw, dblink, and CREATE SUBSCRIPTION security

Robert Haas <robertmhaas@gmail.com>

From: Robert Haas <robertmhaas@gmail.com>
To: Jacob Champion <jchampion@timescale.com>
Cc: Andres Freund <andres@anarazel.de>, Mark Dilger <mark.dilger@enterprisedb.com>, Jeff Davis <pgsql@j-davis.com>, Amit Kapila <amit.kapila16@gmail.com>, Andrew Dunstan <andrew@dunslane.net>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2023-03-09T14:12:37Z
Lists: pgsql-hackers
On Wed, Mar 8, 2023 at 5:44 PM Jacob Champion <jchampion@timescale.com> wrote:
>
> On Wed, Mar 8, 2023 at 11:40 AM Robert Haas <robertmhaas@gmail.com> wrote:
> > On Wed, Mar 8, 2023 at 2:30 PM Jacob Champion <jchampion@timescale.com> wrote:
> > > I don't think I necessarily like that option better than SASL-style,
> > > but hopefully that clarifies it somewhat?
> >
> > Hmm, yeah, I guess that's OK.
>
> Okay, cool.
>
> > I still don't love it, though. It feels
> > more solid to me if the proxy can actually block the connections
> > before they even happen, without having to rely on a server
> > interaction to figure out what is permissible.
>
> Sure. I don't see a way for the proxy to figure that out by itself,
> though, going back to my asymmetry argument from before. Only the
> server truly knows, at time of HBA processing, whether the proxy
> itself has authority. If the proxy knew, it wouldn't be confused.
>
> > I don't know what you mean by SASL-style, exactly.
>
> That's the one where the server explicitly names all forms of
> authentication, including the ambient ones (ANONYMOUS, EXTERNAL,
> etc.), and requires the client to choose one before running any
> actions on their behalf. That lets the require_auth machinery work for
> this case, too.
>
> --Jacob



-- 
Robert Haas
EDB: http://www.enterprisedb.com



Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →
  1. Fix possible crash in tablesync worker.

  2. Display 'password_required' option for \dRs+ command.

  3. Restart the apply worker if the 'password_required' option is changed.

  4. Fix possible logical replication crash.

  5. Add new predefined role pg_create_subscription.

  6. Expand AclMode to 64 bits

  7. More cleanup of a2ab9c06ea.

  8. Respect permissions within logical replication.

  9. Improve table locking behavior in the face of current DDL.