Re: [HACKERS] Enabling replication connections by default inpg_hba.conf

On 2/2/17 8:32 AM, Simon Riggs wrote:
> I think we should remove the "replication" false database concept in
> pg_hba.conf altogether and allow any valid pg_hba rule to invoke a
> replication connection, if one is requested. Roles would still need
> the REPLICATION capability before this would be allowed. Having both
> of those things doesn't materially improve security control.

It's weirdly inconsistent now.  You need a "replication" line in
pg_hba.conf to connect for logical decoding, but you can't restrict that
to a specific database because the database column in pg_hba.conf is
occupied by the "replication" key word.

However, you would still want a way to configure a user for logical
decoding for any database but no physical replication, or vice versa.
Just getting rid of the replication key word would prevent that, I think.

> It would also be useful to be able prevent users with REPLICATION
> capability from connecting as normal users, if the are marked as
> NOLOGIN.

That sounds useful.

(Superusers not have the replication attribute by default is an
additional possible annoyance.)

-- 
Peter Eisentraut              http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services