[Freeipa-devel] KDC proxy implementation specs

[Simo Sorce]

On Thu, 2015-05-28 at 17:00 +0200, Christian Heimes wrote:
> On 2015-05-28 16:53, Simo Sorce wrote:
> > We can't have 2 different keytabs with the same principal name.
> > If we need privilege separation we'll have to work on integrating
> > GSS-Proxy and give the keytab only to GSS-Proxy leaving it off the hands
> > of both the framework, the proxy, and apache itself.
> 
> I had a different principal like KDCPROXY/fqdn at realm in mind.
> 
> > Although to be honest I do not see why the proxy need access to the
> > keytab at all, can we simply run it as a wsgi application under a
> > different user and prevent it from accessing the apache keytab at all ?
> 
> Yes, mod_wsgi is able to run a WSGI app as a different user:
> 
> https://code.google.com/p/modwsgi/wiki/ConfigurationDirectives#WSGIDaemonProcess
> 
> A different user needs another location for the ccache and perhaps
> additional SELinux rules.

If you are using the keytab only to acquire credentials to access ldap
you could use a memory ccache and not have to deal with locations:
KRB5CCNAME=MEMORY:kdcproxy_<random_number>

> > What do we need the keytab for ?
> > Is it just in order to authenticate and read if the service is enabled ?
> > Can we make that information available anonymously ?
> 
> Yes, the information is not available for anon bind. It doesn't feel
> right to disclose the settings to the public.

Another option is to use ldapi and external auth, I forgot if we allow
automatic binding for no-root users though.

Rob,
do you remember ?

Simo.

-- 
Simo Sorce * Red Hat, Inc * New York