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On Thu, 20 Jan 2022 at 18:40, Ghanshyam Mann <gmann at ghanshyammann.com> wrote:
>
>
>  ---- On Thu, 20 Jan 2022 03:35:33 -0600 Mark Goddard <mark at stackhpc.com> wrote ----
>  > On Wed, 19 Jan 2022 at 16:12, Ghanshyam Mann <gmann at ghanshyammann.com> wrote:
>  > >
>  > >  ---- On Wed, 19 Jan 2022 04:35:53 -0600 Mark Goddard <mark at stackhpc.com> wrote ----
>  > >  > Hi,
>  > >  >
>  > >  > If you haven't been paying close attention, it would be easy to miss
>  > >  > some of the upcoming RBAC changes which will have an impact on
>  > >  > deployment projects. I thought I'd start a thread so that we can share
>  > >  > how we are approaching this, get answers to open questions, and
>  > >  > ideally all end up with a fairly consistent approach.
>  > >  >
>  > >  > The secure RBAC work has a long history, and continues to evolve.
>  > >  > According to [1], we should start to see some fairly substantial
>  > >  > changes over the next few releases. That spec is fairly long, but
>  > >  > worth a read.
>  > >  >
>  > >  > In the yoga timeline [2], there is one change in particular that has
>  > >  > an impact on deployment projects, "3. Keystone enforces scope by
>  > >  > default". After this change, all of the deprecated policies that many
>  > >  > still rely on in Keystone will be removed.
>  > >  >
>  > >  > In kolla-ansible, we have an etherpad [5] with some notes, questions
>  > >  > and half-baked plans. We made some changes in Xena [3] to use system
>  > >  > scope in some places when interacting with system APIs in Ansible
>  > >  > tasks.
>  > >  >
>  > >  > The next change we have staged is to add the service role to all
>  > >  > service users [4], in preparation for [2].
>  > >  >
>  > >  > Question: should the role be added with system scope or in the
>  > >  > existing service project? The obvious main use for this is token
>  > >  > validation, which seems to allow system or project scope.
>  > >  >
>  > >  > We anticipate that some service users may still require some
>  > >  > project-scoped roles, e.g. when creating resources for octavia. We'll
>  > >  > deal with those on a case by case basis.
>  > >
>  > > Service roles are planned for phase2 which is Z release[1]. The Idea here is
>  > > service to service communication will happen with 'service' role (which keystone
>  > > need to implement yet) and end users will keep using the what ever role
>  > > is default (or overridden in policy file) which can be project or system scoped
>  > > depends on the APIs.
>  > >
>  > > So at the end service-service APIs policy default will looks like
>  > >
>  > >  '(role:admin and system:network and project_id:%(project_id)s) or (role:service and project_name:service)'
>  > >
>  > > Say nova will use that service role to communicate to cinder and cinder policy will pass
>  > > as service role is in OR in default policy.
>  > >
>  > > But let's see how they are going to be and if any challenges when we will implement
>  > > it in Z cycle.
>  >
>  > I'm not 100% on our reasoning for using the service role in yoga (I
>  > wasn't in the discussion when we made the switch, although John
>  > Garbutt was), although I can provide at least one reason.
>  >
>  > Currently, we have a bunch of service users doing things like keystone
>  > token validation using the admin role in the service project. If we
>  > enforce scopes & new defaults in keystone, this will no longer work,
>  > due to the default policy:
>  >
>  > identity:validate_token: (role:reader and system_scope:all) or
>  > rule:service_role or rule:token_subject
>  >
>  > Now we could go and assign system-reader to all these users, but if
>  > the end goal is to give them all the service role, and that allows
>  > token validation, then to me that seems like a better path.
>  >
>  > Currently, we're creating the service role during deploy & upgrade,
>  > then assigning it to users. Keystone is supposed to create the service
>  > role in yoga, so we can eventually drop that part.
>  >
>  > Does this seem reasonable? Is keystone still on track to create the
>  > service role in yoga?
>
> I think this is a reasonable plan and once we have service roles implemented
> in keystone as well as in all the services to request other service APIs then
> deployment project (Kolla here) can update them from system_reader to
> actual service role.

To be clear, I am proposing to skip system-reader, and go straight to
the service role in yoga.

>
> And yes that can be done for token validation as well as
> the service-to-service API calls for example nova to cinder or neutron to nova
> APIs call. I do not think we can migrate everything (service tokens) together for all
> the services in deployment projects until all these services are ready with the 'service'
> role implementation (implementation means changing their default roles
> to add 'service' role for service-to-service APIs).
>
> Regarding the keystone track on service role work in Yoga or not, I do not
> have clear answer may be Lance or keystone team can answer it. But Lance
> has spec up[1] but not yet merged.
>
> [1] https://review.opendev.org/c/openstack/keystone-specs/+/818616
>
> -gmann
>
>  >
>  > >
>  > >  >
>  > >  > In anticipation of keystone setting enforce_scope=True and removing
>  > >  > old default policies (which I assume effectively removes
>  > >  > enforce_new_defaults?), we will set this in kolla-ansible, and try to
>  > >  > deal with any fallout. Hopefully the previous work will make this
>  > >  > minimal.
>  > >  >
>  > >  > How does that line up with other projects' approaches? What have we missed?
>  > >
>  > > Yeah, we want users/deployment projects/horizon etc to use the new policy from
>  > > keystone as first and we will see feedback how they are (good, bad, really bad) from
>  > > usage perspective. Why we choose keystone is, because new policy are there since
>  > > many cycle and ready to use. Other projects needs to work their policy as per new
>  > > SRBAC design/direction (for example nova needs to modify their policy before we ask
>  > > users to use new policy and work is under progress[2]).
>  > >
>  > > I think trying in kolla will be good way to know if we can move to keystone's new policy
>  > > completely in yoga.
>  >
>  > We have a scope-enforcing preview patch [1], and it's passing our base
>  > set of tests. I have another that triggers all of the jobs.
>  >
>  > [1] https://review.opendev.org/c/openstack/kolla-ansible/+/825406
>  > >
>  > > [1] https://opendev.org/openstack/governance/src/branch/master/goals/selected/consistent-and-secure-rbac.rst#z-release-timeline
>  > > [2] https://blueprints.launchpad.net/nova/+spec/policy-defaults-refresh-2
>  > >
>  > > -gmann
>  > >
>  > >  >
>  > >  > Mark
>  > >  >
>  > >  > [1] https://opendev.org/openstack/governance/src/branch/master/goals/selected/consistent-and-secure-rbac.rst
>  > >  > [2] https://opendev.org/openstack/governance/src/branch/master/goals/selected/consistent-and-secure-rbac.rst#yoga-timeline-7th-mar-2022
>  > >  > [3] https://opendev.org/openstack/kolla-ansible/commit/2e933dceb591c3505f35c2c1de924f3978fb81a7
>  > >  > [4] https://review.opendev.org/c/openstack/kolla-ansible/+/815577
>  > >  > [5] https://etherpad.opendev.org/p/enabling-system-scope-in-kolla-ansible
>  > >  >
>  > >  >
>  >
>  >