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On 01/09/2015 11:38, "Douglas Mendizábal"
<douglas.mendizabal at rackspace.com> wrote:

This turned into exactly what I was trying to avoid, I probably shouldn’t
have mentioned Anchor, but as I started us down this road (where really I
was just expressing some concerns over certificate lifecycle) please see
my comments below :)

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>Added a few comments inline.
>
>- - Douglas Mendizábal
>
>On 9/1/15 12:03 PM, John Dennis wrote:
>> On 09/01/2015 10:57 AM, Clark, Robert Graham wrote:
>>> 
>>>> The reason that is compelling is that you can have Barbican
>>>> generate, sign, and store a keypair without transmitting the
>>>> private key over the network to the client that originates the
>>>>  signing request. It can be directly stored, and made available
>>>>  only to the clients that need access to it.
>>> 
>>> This is absolutely _not_ how PKI for TLS is supposed to work,
>>> yes Barbican can create keypairs etc because sometimes that¹s
>>> useful but in the public-private PKI model that TLS expects this
>>> is completely wrong. Magnum nodes should be creating their own
>>> private key and CSR and submitting them to some CA for signing.
>>> 
>
>Barbican provides a lot of options for provisioning certificates. We
>do support provisioning certs by only passing a CSR so that clients
>can keep ownership of their keys, if that's what the client prefers.
>
>Of course, when you're provisioning keys for every node in a cluster
>for many clusters then key management becomes an issue, and if these
>are not throwaway keys, then storing them in Barbican makes sense.
>
>We can also provision the keys, and create CSRs on the Barbican side,
>so we make it very easy for clients who don't want to do any of this
>locally.

I wasn’t bashing Barbican, just the way that it looks like it’s being used
here, as I said, there’s good reasons why Barbican works the way it does,
but not all available options are appropriate for all types of deployments.



>
>>> Now this gets messy because you probably don¹t want to push
>>> keystone credentials onto each node (that they would use to
>>> communicate with Barbican).
>>> 
>
>Kevin Fox is working on a Nova spec to provide identity to VMs. I'm
>really hoping this spec gains some traction because it's a problem
>that not only Barbican, but all other user-facing projects can benefit
>from.
>
>See: https://blueprints.launchpad.net/nova/+spec/instance-users
>
>>> I¹m a bit conflicted writing this next bit because I¹m not
>>> particularly familiar with the Kubernetes/Magnum architectures
>>> and also because I¹m one of the core developers for Anchor but
>>> here goesŠ.
>>> 
>>> Have you considered using Anchor for this? It¹s a pretty
>>> lightweight ephemeral CA that is built to work well in small PKI
>>>  communities (like a Kubernetes cluster) you can configure
>>> multiple methods for authentication and build pretty simple
>>> validation rules for deciding if a host should be given a
>>> certificate. Anchor is built to provide short-lifetime
>>> certificates where each node re-requests a certificate typically
>>>  every 12-24 hours, this has some really nice properties like
>>> ³passive revocation² (Think revocation that actually works) and
>>> strong ways to enforce issuing logic on a per host basis.
>>> 
>
>Someone from the Magnum team can correct me if I'm wrong, but I do
>believe they considered Anchor for certificate provisioning.
>
>As I understand the Magnum use case, they will be provisioning many
>clusters across different tenants. While Anchor would work well for a
>single cluster, they need the ability to provision new CA roots for
>each and every cluster, and then provision certs off that root for
>every node in the cluster. This way node certs are only valid in the
>context of the cluster.
>
>A new feature for Barbican Liberty will be the ability to add new CA
>roots scoped to a tenant via API, which will address the Magnum
>requirements of separating the certificate roots per cluster.

Interestingly, we recently added support for this, you can have multiple
CA roots within Anchor. When we announced it a few summits back we
focussed on how you can use Anchor in silo’d deployments where you would
spin up an instance for each cluster but recently we added the ability to
run Anchor with multiple CA roots, each can have it’s own auth and it’s
own validation chain.


>
>>> Anchor or not, I¹d like to talk to you more about how you¹re
>>> attempting to secure Magnum - I think it¹s an extremely
>>> interesting project that I¹d like to help out with.
>>> 
>>> -Rob (Security Project PTL / Anchor flunkie)
>> 
>> Let's not reinvent the wheel. I can't comment on what Magnum is
>> doing but I do know the members of the Barbican project are PKI
>> experts and understand CSR's, key escrow, revocation, etc. Some of
>>  the design work is being done by engineers who currently
>> contribute to products in use by the Dept. of Defense, an agency
>> that takes their PKI infrastructure very seriously. They also have
>> been involved with Keystone. I work with these engineers on a
>> regular basis.

To address some of the points above, Anchor and Barbican are complimentary
technologies, I’m not suggesting that one be used over the other, just
that the way that Barbican is being proposed to be used looks scary to me.
As for the people that work on it, I think they’re great! They’re the same
sort of (in some cases exactly the same) people that contribute to Anchor.


>> 
>> The Barbican blueprint states:
>> 
>> Barbican supports full lifecycle management including
>> provisioning, expiration, reporting, etc. A plugin system allows
>> for multiple certificate authority support (including public and
>> private CAs).
>> 
>> Perhaps Anchor would be a great candidate for a Barbican plugin.
>> 
>
>We've talked about this before with the Security team, and I agree
>that adding a CA plugin to Barbican to support Anchor would be awesome.

+1

>
>> What I don't want to see is spinning our wheels, going backward,
>> or inventing one-off solutions to a very demanding and complex
>> problem space. There have been way too many one-off solutions in
>> the past, we want to consolidate the expertise in one project that
>> is designed by experts and fully vetted, this is the role of
>> Barbican. Would you like to contribute to Barbican? I'm sure your
>> skills would be a tremendous asset.
>> 
>> 
>
>Rob does help out on Barbican occasionally, and I agree his skills are
>a tremendous asset. :)

I have a lot of love for Barbican, just not enough time!

>