Intel SGX admission controller for Kubernetes
Table of Contents
The SGX admission controller is one of the components used to add support for Intel SGX functionality to Kubernetes.
NOTE: Installation of the SGX admission controller can be skipped if the SGX device plugin is operated with the Intel Device Plugins Operator since it integrates the controller’s functionality.
The SGX admission webhook is responsible for performing Pod mutations based on the
pod annotation set by the user. The purpose of the webhook is to hide the details of setting the necessary
device resources and volume mounts for using SGX remote attestation in the cluster. Furthermore,
the SGX admission webhook is responsible for writing a pod/sandbox
sgx.intel.com/epc annotation that is used by
Kata Containers to dynamically adjust its virtualized SGX encrypted page cache (EPC) bank(s) size.
The following sections detail how to obtain, build and deploy the admission controller webhook plugin.
The default webhook deployment depends on having cert-manager installed. See its installation instructions here.
Also if your cluster operates behind a corporate proxy make sure that the API server is configured not to send requests to cluster services through the proxy. You can check that with the following command:
$ kubectl describe pod kube-apiserver --namespace kube-system | grep -i no_proxy | grep "\.svc"
In case there’s no output and your cluster was deployed with
/etc/kubernetes/manifests/kube-apiserver.yaml at the control plane nodes and
.svc.cluster.local to the
no_proxy environment variable:
apiVersion: v1 kind: Pod metadata: ... spec: containers: - command: - kube-apiserver - --advertise-address=10.237.71.99 ... env: - name: http_proxy value: http://proxy.host:8080 - name: https_proxy value: http://proxy.host:8433 - name: no_proxy value: 127.0.0.1,localhost,.example.com,10.0.0.0/8,.svc,.svc.cluster.local ...
Note: To build clusters using
kubeadm with the right
no_proxy settings from the very beginning,
set the cluster service names to
$ export no_proxy=$no_proxy,.svc,.svc.cluster.local
To deploy the webhook with cert-manager, run
$ kubectl apply -k https://github.com/intel/intel-device-plugins-for-kubernetes/deployments/sgx_admissionwebhook/overlays/default-with-certmanager?ref=main