Horton

Re: Password identifiers, protocol aging and SCRAM protocol

David Fetter <david@fetter.org>

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From: David Fetter <david@fetter.org>
To: Alvaro Herrera <alvherre@2ndquadrant.com>
Cc: Michael Paquier <michael.paquier@gmail.com>, Magnus Hagander <magnus@hagander.net>, Peter Eisentraut <peter.eisentraut@2ndquadrant.com>, Heikki Linnakangas <hlinnaka@iki.fi>, Robert Haas <robertmhaas@gmail.com>, Julian Markwort <julian.markwort@uni-muenster.de>, Stephen Frost <sfrost@snowman.net>, David Steele <david@pgmasters.net>, PostgreSQL mailing lists <pgsql-hackers@postgresql.org>, Valery Popov <v.popov@postgrespro.ru>
Date: 2016-07-20T20:25:24Z
Lists: pgsql-hackers 
On Wed, Jul 20, 2016 at 02:12:57PM -0400, Alvaro Herrera wrote:
> Michael Paquier wrote:
> > On Wed, Jul 6, 2016 at 4:18 PM, Michael Paquier
> > <michael.paquier@gmail.com> wrote:
> > > OK, after hacking that for a bit I have finished with option 2 and the
> > > set of PG-like set of routines, the use of USE_SSL in the file
> > > containing all the SHA functions of OpenBSD has proved to be really
> > > ugly, but with a split things are really clear to the eye. The stuff I
> > > got builds on OSX, Linux and MSVC. pgcrypto cannot link directly to
> > > libpgcommon.a, so I am making it compile directly with the source
> > > files, as it is doing on HEAD.
> > 
> > Btw, attached is the patch I did for this part if there is any interest in it.
> 
> After quickly eyeballing your patch, I agree with the decision of going
> with (2), even if my gut initially told me that (1) would be better
> because it'd require less makefile trickery.
> 
> I'm surprised that you say pgcrypto cannot link libpgcommon directly.
> Is there some insurmountable problem there?  I notice your MSVC patch
> uses libpgcommon while the Makefile symlinks the files.

People have, in the past, expressed concerns about linking in
pgcrypto.  Apparently, in some countries, it's a legal problem.

Best,
David.
-- 
David Fetter <david(at)fetter(dot)org> http://fetter.org/
Phone: +1 415 235 3778  AIM: dfetter666  Yahoo!: dfetter
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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.