Message-ID: <5150610E.3090706@kcl.ac.uk>
Date: Mon, 25 Mar 2013 14:37:02 +0000
From: Tim Watts <tim.j.watts@kcl.ac.uk>
User-Agent: Mozilla/5.0 (X11; Linux x86_64;
	rv:17.0) Gecko/20130308 Thunderbird/17.0.4
MIME-Version: 1.0
To: Stephen Frost <sfrost@snowman.net>
CC: "pgsql-admin@postgresql.org" <pgsql-admin@postgresql.org>
Subject: Re: Postgresql 8.4 GSSAPI auth with fallback to password
 prompting?
References: <514AFB73.6050300@kcl.ac.uk>
	<5c910ac4f9fa4dc78f1ba6747182b671@DBXPRD0310HT003.eurprd03.prod.outlook.com>
	<51502949.6000903@kcl.ac.uk>
	<41b629dc89ba459b89bd1ccc20624326@DBXPRD0310HT005.eurprd03.prod.outlook.com>
In-Reply-To: 
 <41b629dc89ba459b89bd1ccc20624326@DBXPRD0310HT005.eurprd03.prod.outlook.com>
Content-Type: text/plain; charset="ISO-8859-1"; format=flowed
Content-Transfer-Encoding: 7bit
Precedence: bulk
Sender: pgsql-admin-owner@postgresql.org

On 25/03/13 13:25, Stephen Frost wrote:
> Tim,
>
> * Tim Watts (tim.j.watts@kcl.ac.uk) wrote:
>> I would have to respectfully take another point of view: that that
>> particular judgement is probably better placed with the sysadmin
>> rather than a blanket decision by the devs.
>
> It's not a blanket decision by any means- the current situation is that
> such an option doesn't exist.  It's not "it exists, but we disabled it
> because we felt like it."
>
> Were someone to write the code to support such an option, it's entirely
> possible it'd get committed (though likely with strong caveats about its
> use in the documentation).

That's totally fair... Not sure if I could. I hacked an option into 
Samba from a cold start once. On an equal footing, OpenLDAP's source 
code totally defeated me ;-> I might have a look to see if it looks 
"trivial" or "hard".

>> Reason: Whilst the argument is solid in an ideal world (all clients
>> are part of the kerberos realm), in reality it means that I cannot
>> gain partial security improvements and I have to leave it running
>> with PAM auth which ensures that passwords are chucked around 100%
>> of the time.
>
> The pg_hba.conf allows you to migrate users or sets of users at a time.
> Having a fall-back mechanism if Kerberos doesn't work is a different
> thing.  My experience has been that all clients (or at least, all in a
> given IP range or for a set of users) *are* part of the Kerberos realm
> because they're coming from Active Directory or another entrenched
> Kerberos installation.  That's specifically because that's how
> Kerberos is intended to work and how it provides a strong
> authentication mechanism.

I think that laptops[1] and "BYOD" (Bring your own device, eg *pads) are 
going to make that scenario less common.

[1] OK - it is perfectly possible to have a managed laptop. But it's 
harder than a managed desktop so I've not seen it outside of very large 
corporations with draconian policies on using their and only their devices.

>> But it would be nice to be able to use kerberos tickets *where
>> available* and fallback to password-interactive login where not.
>
> And I continue to contend that this is a very bad idea.

But less bad than not using kerberos for anything...

Cheers

Tim
-- 
Tim Watts                               Tel (VOIP): +44 (0)1580 848360
Systems Manager              Digital Humanities, King's College London

Systems Messages and Notifications: https://systemsblog.cch.kcl.ac.uk/
Personal Blog:                         http://squiddy.blog.dionic.net/

"She got her looks from her father. He's a plastic surgeon."


-- 
Sent via pgsql-admin mailing list (pgsql-admin@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-admin