[Freeipa-users] Limiting Host access by UID/GID

[Jakub Hrozek]

On Fri, May 31, 2013 at 08:50:29AM -0700, Chandan Kumar wrote:
> As far as my understanding goes it does not stop even if I disable cache
> credentials. I set following parameters in sssd.conf but still UID 20000 is
> able to login.
> 

Sorry, there was some terminology confusion. I didn't ask for disabling
cache credentials, but removing the on-disk cache and starting afresh.

The cache is stored in /var/lib/sss/db/cache_$domname.ldb, so you can mv
or rm it and check again if the IDs are still allowed.

> cache_credentials = False
> krb5_store_password_if_offline = False
> min_id=5000
> max_id=5010
> enumerate = False
> entry_cache_timeout=3
> 
> Package Info:
> Client;
> sssd-client-1.9.2-82.7.el6_4.x86_64
> 
> Server:
> ipa-server-2.2.0-16.el6.x86_64
> 
> Thanks
> Chandan
> 
> On Friday, May 31, 2013, Jakub Hrozek wrote:
> 
> > On Fri, May 31, 2013 at 09:26:40AM -0400, Simo Sorce wrote:
> > > On Fri, 2013-05-31 at 11:55 +0200, Jakub Hrozek wrote:
> > > > On Thu, May 30, 2013 at 07:23:38PM -0400, Dmitri Pal wrote:
> > > > > On 05/30/2013 06:52 PM, Chandan Kumar wrote:
> > > > > > Hello,
> > > > > >
> > > > > > As part of migration from passwd/shadow to IPA, I want to roll out
> > > > > > IPA/SSSD based password first for a small number of users and then
> > for
> > > > > > all. (same goes with host. first small number of host and then
> > all).
> > > > > >
> > > > > > I was trying to limit it using max_id/min_id parameters in sssd
> > but it
> > > > > > does not seems to work the way I expected.
> > > > > > -------
> > > > > > min_id = 5000
> > > > > > max_id = 5100
> > > > > > ------
> > > > > > So there is a user "kchandan" with UID/GID 20000
> > > > > > ------
> > > > > > [root at tipa1 ~]# id kchandan
> > > > > > uid=20000(kchandan) gid=20000 groups=20000
> > > > > > -------
> > > > > >
> > > > > > But It is allowing me to login with that ID with only error showing
> > > > > > GID 20000 not found.
> > > > > > -----------
> > > > > > ssh 10.2.3.105 -l kchandan
> > > > > > kchandan at 10.2.3.105 <mailto:kchandan at 10.2.3.105>'s password:
> > > > > > id: cannot find name for group ID 20000
> > > > > > -------------
> > > > > >
> > > > > > Is there any way to achieve this?
> > > > >
> > > > > So you want to allow only a subset of users with a specific range to
> > log
> > > > > into the systems controlled by SSSD before you open it to a broader
> > public?
> > > > > I would defer to SSSD gurus but the hack that comes to mind is to
> > > > > configure a simple access provider to limit the access to just the
> > users
> > > > > you care about (man sssd-simple) or configure ldap access provider
> > based
> > > > > on a filter (man sssd-ldap).
> > > >
> > > > Hi,
> > > >
> > > > The user shouldn't be even saved to cache if it's filtered out of
> > range.
> > > >
> > > > But looking at the current NSS code, the entry would have been
> > returned if
> > > > it was saved *before* you changed the min_id/max_id parameters. Could
> > that be
> > > > the case? Can you check if after removing the cache the entry still
> > shows up?
> > > >
> > > > I think that the fact that the entry is returned from cache even if it
> > > > should be filtered out is a bug:
> > > > https://fedorahosted.org/sssd/ticket/1954
> > >
> > > So far we always maintained that if you consistently change
> > > configuration (and a change of ranges is a big change) then it's on the
> > > admin to wipe the cache file.
> >
> > Yes, that's why the ticket is minor. But mostly I don't like the
> > inconsistency where some requests check the ranges even in the responder
> > and some don't.
> >
> > _______________________________________________
> > Freeipa-users mailing list
> > Freeipa-users at redhat.com
> > https://www.redhat.com/mailman/listinfo/freeipa-users
> >
> 
> 
> -- 
> 
> --
> http://about.me/chandank