Open Stack

At Rackspace, we've attempted to mitigate this be requiring products that
want to cache user tokens to listen to an ATOM feed that our identity
system exposes that tracks user state changes. When a tenant is disabled,
a message appears on the ATOM feed, which the products use to invalidate
the cache entry.

It's not super great (ATOM is still polling), but it does allow some
guarantee that an existing token will get revoked within x minutes from
invalidation, usually less than 5.


I think this functionality is build into repose, our rest proxy. It's open
source if people want to poke at it:

http://openrepose.org/



Jarret




On 8/7/13 7:33 AM, "Clark, Robert Graham" <robert.clark at hp.com> wrote:

>[DRAFT] - Please Review
>Disabling a tenant does not disable a user token
>----
>
>### Summary ###
>When a tenant is disabled in Keystone, tokens that have been issued to
>that tenant are not invalidated. This can result in users having access
>to your cloud after you have attempted to revoke them.
>
>### Affected Services / Software ###
>Keystone
>
>### Discussion ###
>It appears that Keystone does not purge the tokens given out to tenants
>when a tenant is disabled. In some scenarios this could be very
>important to cloud providers. Take the case where a cloud provider must
>a tenant's access because of some legal investigation. Even though the
>tenant is disabled it would be possible for them to terminate VMs /
>delete Swift files etc. - There are many other abuse-cases...
>
>### Recommended Actions ###
>How the tokens are stored depends on your cloud deployment. If you
>deploy using Memcache to back Keystone then flushing the cash when
>disabling a token would resolve this issue for you, at the cost of other
>token lookups which are no longer in the cash requiring Keystone
>interaction.
>
>It is of course possible to script something to remove tokens from any
>backend DB or cache but there is no 'official' way to do this.
>
>### Contacts / References ###
>Proposed Fix : https://review.openstack.org/#/c/39878/
>This OSSN : https://bugs.launchpad.net/ossn/+bug/1179955
>OpenStack Security ML : openstack-security at lists.openstack.org
>OpenStack Security Group : https://launchpad.net/~openstack-ossg