On Fri, 2018-05-11 at 13:52 -0400, Rob Crittenden wrote:
Simo Sorce wrote:
> On Fri, 2018-05-11 at 15:47 +1000, Fraser Tweedale via FreeIPA-devel
> > Hi all,
> > Ticket https://pagure.io/freeipa/issue/7482
made me think about the
> > current revocation behaviour in `ipa cert-request`. For hosts and
> > services, all old certificates get revoked.
> > I wrote a blog post outlining the problems with the current
> > behaviour, and some suggested changes. I'd like to know others'
> > thoughts. If we go ahead it would be something for a major release,
> > not a bugfix release. The actual amount of work is pretty small.
> > 
> I'd prefer no revocation by default, if people need two+ certs with the
> same name they should be able to do so easily (for example for
> clustered services that need to answer as a single machine).
Multiple certs is fine but the convention to date has been one cert per
service so that usage can be more easily tracked. If they want that can
have a single cert and share it everywhere but then things are more
opaque and the systems harder to manage. You can't easily answer the
question "What TLS services are we running on bob?"
I am not sure this is such a huge winner though.
First of all that tracking is expensive for our directory, and we
should think if it is worth.
A lot of systems have certs not IPA based anyway (public certs, private
domain specific CAs, etc... so IPA is not the source of all truth for
TLS certs anyway.
I can't quite get my head around Fraser's scenario
Certificate for new
purpose (non-renewal). New purpose for the same service? Do you have any
examples of that?
Simple cases are needing certs for both Apache, Postfix and IMAP, all
sharing the same name for ease of configuration by mail clients.
Also think about load balancers serving behind a DNS round robin
service, and they have HSMs
It is more ideal to have multiple certs in that case thn copying around
This is a bit out there, but in general not sharing the key when
multiple services use the same name is a win.
(for example if only one system is compromised you can revoke that
system's specific cert and not have to take a full outage to rotate
cert and keys on all systems, etc...)
Beyond the fact that we'll have to come up with some other scheme
sift the database looking for expired certs to remove from usercertificate.
Not sure I understand this point
Remember that storing usercertificate in host/service entries
really no value whatsoever except to pin the fact that the service has a
certificate at all. So being able to store 0, 1 or more doesn't really
buy you a lot unless you are using these services to bind as clients.
Even now when you display a service it provides the details for only ONE
I would not store the cert unless we have a good reason for it.
I would think dogtag can already do tracking and we do not need to do
it again in DS.
user certs are another story altogether and not covered here.
> It also fills a CRL list for no good reasons, we should be conservative
> on CRL size, and if someone has a dynamic environment where hosts are
> created and destroyed frequently the CRL could become enormous.
Sure, assuming they actually use the CRL or OCSP.
I'd be ok making it a config option.
I think I'd rather not extend the cert-request API for the revocation
case and use post-command scripts to do it instead. This is an IPA
policy so it should live within IPA.
Is it a IPA policy ? Or should it be controlled by admins ?
I think I am getting in the camp that admins/cert owners should decide
if they want to revoke a cert. Doing it automatically has some
benefits, but in time I came around to think the negatives are more
than the positives.
Sr. Principal Software Engineer
Red Hat, Inc