This fork allow signing csr request with kubernetes.io/legacy-unknown signer. This is usefull for distribution which for security reasons don't implement kube-controller-manager signing feature and remove CA from the hosts himself.

signer-ca

signer-ca is an operator for automatically signing an approved CertificateSigningRequest.

NOTE: This operator is EXPERIMENTAL and requires Kubernetes >= 1.18. It uses Certificates API Enhancements which are only available in Kubernetes >= 1.18.

It watches CertificateSigningRequest (CSR) resources and if the CSR has a .spec.signerName that it recognizes, and if the CSR has been approved, it creates a signed certificate using a certificate-authority file that you supply as a command-line argument to the operator. The signed certificate is configured using the encoded CSR in .spec.request. The signed certificate is added to the .status.certificate of the CSR resource.

Installation

signer-ca can be deployed using kubectl -k config/default. See config/e2e for an example of how to make a CA file available to the operator, as a mounted secret.

Build

You can build and deploy signer-ca using make docker-build docker-push deploy-e2e DOCKER_PREFIX=gcr.io/<YOUR_PROJECT>/signer-ca/. See the Makefile for details.

Demo