On Wed, Mar 9, 2022 at 1:57 PM Takashi Kajinami <tkajinam@redhat.com> wrote:
>
> Hello,
>
>
> I've been working on updating policy rules in heat according to the latest
> guideline for SRBAC implementation.

Thanks so much for working on it, definitely +1 on enhancing security.

>
> [1] https://governance.openstack.org/tc/goals/selected/consistent-and-secure-rbac.html#direction-change
>
> However this change reveals one potential issue with system resources.
>
> In heat there are some resource types like OS::Nova::Flavor or OS::Keystone::User
> which is allowed for only system users. (I'll call these resources as "system resources" here)

We create those resources based on checking `role:admin`, so project admin is accepted.

This means a user under that project with role:admin, can operate those resources.

I'm not sure what system user means here, so correct me if I'm wrong.

>
> Because heat uses user credentials to create resources in backend services, if we require
> project scope for stack/resource management then we are no longer able to create these system
> resources as part of stack. (*1)

>
> There are some options I can think of at this moment.
>
> 1. Deprecate and remove all resources which require system scope
> Pros
> - This is most easy solution to be implemented
> Cons
> - This one has the biggest user impact

Don't :)

> 2. Use service credential for resource creation
> Pros:
> - This might have smallest user impact
> Cons:
> - This requires a relatively big change in heat's architecture, which I've not yet evaluated.
> - We need to determine the project scope role to be allowed to do system operation.
>

I think this is something we can discuss more.

> 3. Implement additional project-role in each service to allow creation via stack creation.
> Pros:
> - This would avoid user impact.
> Cons:
> - requires work in multiple components.
> - We need to determine the project scope role to be allowed to do system operation

Indeed current stack operation require `(role:admin and system_scope:all) OR (role:member and project_id:%(project_id)s)`.

And if we remove the system part and keep `(role:member and project_id:%(project_id)s)`, will mean only a user in that project with a member role can operate stack, and if the user got also admin role, that user can manage User/Flavor resources through stack too.

Also, note that

For the case of Nova::Flavor, both policies from Nova and Heat resource will be enforced here, so it only accepts the intersection part of rules.

So if we go with removing the system admin, that means it's time to also remove some deprecated global scope operation.

IMO, to accept Project Admin or member make more reasonable (like you proposed in option 3)

>
> Thank you,
> Takashi
>