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 sgx.intel.com/quote-provider
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 simplest webhook deployment depends on having cert-manager installed:
$ kubectl apply -f https://github.com/jetstack/cert-manager/releases/download/v1.3.1/cert-manager.yaml
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 kubeadm
open
/etc/kubernetes/manifests/kube-apiserver.yaml
at the control plane nodes and
append .svc
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 $no_proxy
before kubeadm init
:
$ 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