Provide image signing configuration operator

[toshiyamamoto]

In order to automate the configuration for the image signing and verification, an operator needs to be used. It takes a Image Signing custom resource to generate a keypair for image signing/verification, place a secret key as a secret for a sign task, generates policy.json and a file under registries.d directory to configure each node for enforcing image signature verification. And minor configurations for the sign task. It's a container image written by Go. This operator is cluster scope, so it needs to be placed openshift-operators namespace.

This task contains following tasks:

• Define ImageSIgning custom resource definition which covers all configuration parameters which are required to configure the end to end scenarios of the image signing and verification.
• Develop Image signing operator, and an container image which contains it.
• Package above two as an operator lifecycle management (OLM).
• If there is not a separate issue, integrate the package to ICP4A installation

[toshiyamamoto]

moved out to a security issue #49