RBAC Manager was designed to simplify authorization in Kubernetes. This is an operator that supports declarative configuration for RBAC with new custom resources. Instead of managing role bindings or service accounts directly, you can specify a desired state and RBAC Manager will make the necessary changes to achieve that state.
This project has three main goals:
- Provide a declarative approach to RBAC that is more approachable and scalable.
- Reduce the amount of configuration required for great auth.
- Enable automation of RBAC configuration updates with CI/CD.
To fully understand how RBAC Manager works, it’s helpful to walk through a simple example. In this example we’ll have a single user, Joe, that needs
edit access to the
web namespace and
view access to
With RBAC, that requires creating 2 role bindings, the first grants
edit access to the
kind: RoleBinding apiVersion: rbac.authorization.k8s.io/v1 metadata: name: joe-web namespace: web subjects: - kind: User name: firstname.lastname@example.org roleRef: kind: ClusterRole name: edit apiGroup: rbac.authorization.k8s.io
The second grants
view access to the
kind: RoleBinding apiVersion: rbac.authorization.k8s.io/v1 metadata: name: joe-api namespace: api subjects: - kind: User name: email@example.com roleRef: kind: ClusterRole name: view apiGroup: rbac.authorization.k8s.io
It’s easy to see just how repetitive this becomes. With RBAC Manager, we can use a custom resource to achieve the same result.
apiVersion: rbacmanager.reactiveops.io/v1beta1 kind: RBACDefinition metadata: name: joe-access rbacBindings: - name: joe subjects: - kind: User name: firstname.lastname@example.org roleBindings: - namespace: api clusterRole: view - namespace: web clusterRole: edit
With an RBAC Definition custom resource, we can cut the amount of configuration in half (or often significantly more). RBAC Manager is deployed as an operator and listens for new and updated RBAC Definitions, making the necessary changes to achieve the desired state.
This approach is incredibly helpful for 2 specific cases:
1. Updating a Role Binding
Unfortunately there’s no way to change the role an existing Kubernetes Role Binding refers to. That means that changing a role granted to a user involves deleting and recreating a Kubernetes Role Binding. With RBAC Manager, that process happens automatically when an RBAC Definition is updated.
2. Detecting Role Binding Removal
When it comes to potential CI automation of changes to RBAC configuration, tracking the removal of a role binding can get quite tricky. If you were using a traditional workflow where desired Kubernetes objects are represent in a repo as yaml files, the creates and updates are reasonably straightforward, but revoking access on the basis of a Role Binding being removed is quite tricky.
With RBAC Manager, each RBAC Definition “owns” any resources it creates, and will always compare the desired state in the current RBAC Definition with the list of resources currently owned by it. If a Role Binding is no longer included in a RBAC Definition, RBAC Manager will automatically remove it.
RBAC Manager is simple to install with either the Helm chart or Kubernetes deployment YAML included in this repo:
helm repo add fairwinds-stable https://charts.fairwinds.com/stable helm install fairwinds-stable/rbac-manager --name rbac-manager --namespace rbac-manager
kubectl apply -f deploy/
Once RBAC Manager is installed in your cluster, you’ll be able to deploy RBAC Definitions to your cluster. There are examples of these custom resources above as well as in the examples directory of this repository.
Dynamic Namespaces and Labels
RBAC Definitions can now include
namespaceSelectors in place of
namespace attributes when specifying Role Binding configuration. This can be incredibly helpful when working with dynamically provisioned namespaces.
apiVersion: rbacmanager.reactiveops.io/v1beta1 kind: RBACDefinition metadata: name: dev-access rbacBindings: - name: dev-team subjects: - kind: Group name: dev-team roleBindings: - clusterRole: edit namespaceSelector: matchLabels: team: dev
In the example above, Role Bindings would automatically get created for each Namespace with a
team=dev label. This supports the same functionality as other Kubernetes label selectors, read the official docs for more information.
RBAC Definitions can manage Cluster Role Bindings, Role Bindings, and Service Accounts. To better understand how these work, read our RBAC Definition documentation.
Cloud Specific Authentication Tips
To properly configure authorization with RBAC in Kubernetes, you first need to have good authentication. We’ve provided some helpful documentation for working with authentication on AWS, Google Cloud, and Azure.
Better Visibility With RBAC Lookup
We have a related open source tool that allows you to easily find roles and cluster roles attached to any user, service account, or group name in your Kubernetes cluster. If that sounds interesting, take a look at rbac-lookup on GitHub.
Apache License 2.0