Re: Postgres 11 release notes - Mailing list pgsql-hackers

On Fri, May 11, 2018 at 11:08:52AM -0400, Bruce Momjian wrote:
> I have committed the first draft of the Postgres 11 release notes.  I
> will add more markup soon.  You can view the most current version
> here:

Thanks for gathering all the commits in one piece, Bruce.

> I expect a torrent of feedback.  ;-)

I looked at the entries where my name shows up.  Here is some feedback
with HEAD at 8c6227a2 (latest as of writing this message).

<para>
 Add information_schema columns related to table constraints and
 triggers (Michael Paquier)
</para>
The author of this entry is Peter Eisentraut, not me.

<para>
 Channel binding requires the server end
 of the <acronym>TLS</acronym> connection to
 prove that it knows the password.  The options are <link
 linkend="libpq-scram-channel-binding"><option>scram_channel_binding=tls-unique</option></link>
 and <option>scram_channel_binding=tls-server-end-point</option>.
</para>
This is not actually correct.  Channel binding is an MITM prevention
mechanism which makes sure that after the SSL handshake the backend and
the frontend are still connected to the same things.  "tls-unique" makes
sure that a connection is uniquely used using a hash of the TLS finish
 message, and end-point makes sure that the endpoints are the same using
 a hash of the server certificate.

<para>
 WHAT DOES THIS DOC TEXT MEAN?  "An empty value specifies that
 the client will not use channel binding.  The default value
 is tls-unique."
</para>
This means that the client can choose to not use channel binding (which
sends a 'n' flag if you refer to the communication protocol of SCRAM),
even if the server has advertised to the client channel binding.  So
this provides a way to disable the feature at will, an on/off switch if
you want.  If a v10 libpq tries to connect to a v11 server, then it
won't use channel binding automatically.  That may be worth adding to
the documentation as well.

<para>
 Allow access to file system functions to be controlled by
 <command>GRANT</command>/<command>REVOKE</command> permissions,
 rather than super-user checks (Michael Paquier)
</para>
Author is Stephen Frost here.

<para>
 Use <command>GRANT</command>/<command>REVOKE</command>
 to control access to <link
 linkend="lo-import"><function>lo_import()</function></link>
 and <function>lo_export()</function> (Michael Paquier)
</para>
Tom Lane is a co-author here I think.

<para>
 Add libpq parameter to allow physical and logical replication
 connections (Michael Paquier)
</para>
This commit has just added documentation which was missing and
incomplete.  I would suggest to remove it from the release notes as no
new feature has been added.

<para>
 Add <link
 linkend="app-pgreceivewal"><application>pg_receivewal</application></link>
 option <option>--no-sync</option> to prevent synchronous
 <acronym>WAL</acronym> writes (Michael Paquier)
</para>
Perhaps this should be rewritten?  --no-sync just disables any fsync
calls for WAL segments, which is useful for tests, not recommended for
production environments.

<para>
 Prevent <application>pg_rewind</application> from running as
 <literal>root</literal> (Magnus Hagander)
</para>
This one's authorship is actually mine, after a bug I found :)
--
Michael