Re: [PATCH] user mapping extension to pg_ident.conf

On Wed, Jul 22, 2009 at 14:53, Tom Lane<tgl@sss.pgh.pa.us> wrote:
> Magnus Hagander <magnus@hagander.net> writes:
>>> Yup, you would need a protocol change that would allow the client to
>>> change its mind about what the username was after it got the auth
>>> challenge.  And then what effects does that have on username-sensitive
>>> pg_hba.conf decisions?  We go back and change our minds about the
>>> challenge type, perhaps?  The whole thing seems like a nonstarter to me.
>
>> "challenge type"? Not sure I understand what you are referring to here.
>
> The point is that pg_hba.conf allows the selection of auth method to
> depend on username.  What happens if, after being told auth method is
> (say) Kerberos, the client comes back and wants to use a different
> username that should have resulted in a different auth method according
> to pg_hba.conf?  It's not hard to construct scenarios where that would
> be seen as a security breach.

Oh. Now I get it. Good point. Forgot about the username being part of
that. Yeah, that basicalliy says it has to be a client-side
implementation only.

-- Magnus HaganderSelf: http://www.hagander.net/Work: http://www.redpill-linpro.com/