Horton

Re: pg_authid.rolpassword format (was Re: Password identifiers, protocol aging and SCRAM protocol)

Michael Paquier <michael.paquier@gmail.com>

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From: Michael Paquier <michael.paquier@gmail.com>
To: Stephen Frost <sfrost@snowman.net>
Cc: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>, Heikki Linnakangas <hlinnaka@iki.fi>, Robert Haas <robertmhaas@gmail.com>, Andres Freund <andres@anarazel.de>, David Steele <david@pgmasters.net>, Tom Lane <tgl@sss.pgh.pa.us>, David Fetter <david@fetter.org>, Alvaro Herrera <alvherre@2ndquadrant.com>, Magnus Hagander <magnus@hagander.net>, Julian Markwort <julian.markwort@uni-muenster.de>, PostgreSQL mailing lists <pgsql-hackers@postgresql.org>, Valery Popov <v.popov@postgrespro.ru>
Date: 2016-12-17T03:48:30Z
Lists: pgsql-hackers 
On Sat, Dec 17, 2016 at 10:23 AM, Stephen Frost <sfrost@snowman.net> wrote:
> * Michael Paquier (michael.paquier@gmail.com) wrote:
>> (Robert you were in this set at this point), and the same thing was
>> concluded during the informal lunch meeting at PGcon. The point is,
>> the existing SCRAM patch set can survive without touching at *all* the
>> format of pg_authid. We could block SCRAM authentication when
>> "password" is used in pg_hba.conf and as well as when "scram" is used
>> with a plain password stored in pg_authid. Or look at the format of
>> the string in the catalog if "password" is defined and decide the
>> authentication protocol to follow based on that.
>
> As I mentioned up-thread, moving forward with minimal changes to get
> SCRAM in certainly makes sense, but I do think we should be open to
> (and, ideally, encouraging people to work towards) having a seperate
> table for verifiers with independent columns for type and verifier.

Definitely, and you know my position on the matter or I would not have
written last year's patch series. Both things are just orthogonal IMO
at this point. And it would be good to focus just on one problem at
the moment to get it out.
-- 
Michael

Commits

  1. Support SCRAM-SHA-256 authentication (RFC 5802 and 7677).

  2. Refactor SHA2 functions and move them to src/common/.

  3. Replace isMD5() with a more future-proof way to check if pw is encrypted.

  4. Remove bogus notice that older clients might not work with MD5 passwords.

  5. Refactor the code for verifying user's password.

  6. Replace PostmasterRandom() with a stronger source, second attempt.

  7. Remove support for (insecure) crypt authentication.