Re: [pgAdmin4][Patch] - RM 5457 - Kerberos Authentication - Phase 1

Greetings Dave!

* Dave Page (dpage@pgadmin.org) wrote:
> On Sat, 2 Jan 2021 at 15:41, Stephen Frost <sfrost@snowman.net> wrote:
> > * Khushboo Vashi (khushboo.vashi@enterprisedb.com) wrote:
> > > Please find the attached patch to support Kerberos Authentication in
> > > pgAdmin RM 5457.
> > >
> > > The patch introduces a new pluggable option for Kerberos authentication,
> > > using SPNEGO to forward kerberos tickets through a browser which will
> > > bypass the login page entirely if the Kerberos Authentication succeeds.
> >
> > I've taken a (very short) look at this as it's certainly something that
> > I'm interested in and glad to see work is being done on it.
> >
> > I notice that 'delegated_creds' is being set but it's unclear to me how
> > they're actually being used (if at all), which is a very important part
> > of Kerberos.
> >
> > What's commonly done with mod_auth_kerb/mod_auth_gss is that the
> > delegated credentials are stored on the filesystem in a temporary
> > directory and then an environment variable is set to signal to libpq /
> > the Kerberos libraries that the delegated credentials can be found in
> > the temporary file.  I don't see any of that happening in this patch- is
> > that already handled in some way?  If not, what's the plan for making
> > that work?  Also important is to make sure that this approach will work
> > for constrainted delegation implementations.
>
> Phase 1 of this project (which this patch aims to implement) is to handle
> Kerberos logins to pgAdmin when running in server mode (as we’ve already
> done for LDAP, except KRB authenticated users don’t see a login page of
> course). Phase 2 will add support for logging into the PostgreSQL servers -
> I believe that is where we’ll need to handle delegated credentials, correct?

Yes, though I sure hope there isn't a plan to release just 'phase 1'
since that would imply that the user is still sending their password to
pgAdmin in some form that pgAdmin then turns around and impersonates the
user, basically completely against how Kerberos auth should be working
in this kind of a intermediate service arrangement.

In other words, if just 'phase 1' is released, it'd probably be CVE
worthy right out of the gate...