Add comment and validation about current unsupported configuration

[nak3]

dataplane-trust and controlplane-trust have many options but most of them are not supported. (And IIUC it will not supported in the near feature.)

networking/config/config-network.yaml

Lines 183 to 206 in 964322c

	# dataplane-trust indicates the level of trust established in the knative data-plane.
	# dataplane-trust = "disabled" (the default) - uses no encryption for internal data plane traffic
	# Using any other value ensures that the following traffic is encrypted using TLS:
	# - ingress to activator
	# - ingress to queue-proxy
	# - activator to queue-proxy
	#
	# dataplane-trust = "minimal" ensures data messages are encrypted, Kingress authenticate that the receiver is a Ksvc
	# dataplane-trust = "enabled" same as "minimal" and in addition, Kingress authenticate that Ksvc is at the correct namespace
	# dataplane-trust = "mutual" same as "enabled" and in addition, Ksvc authenticate that the messages come from the Kingress
	# dataplane-trust = "identity" same as "mutual" with Kingress adding a trusted sender identity to the message
	#
	# NOTE: This flag is in an alpha state and is mostly here to enable internal testing for now. Use with caution.
	dataplane-trust: "disabled"
	# controlplane-trust indicates the level of trust established in the knative control-plane.
	# controlplane-trust = "disabled" (the default) - uses no encryption for internal control plane traffic
	# Using any other value ensures that control traffic is encrypted using TLS.
	#
	# controlplane-trust = "enabled" ensures control messages are encrypted using TLS (client authenticate the server)
	# controlplane-trust = "mutual" ensures control messages are encrypted using mTLS (client and server authenticate each other)
	#
	# NOTE: This flag is in an alpha state and is mostly here to enable internal testing for now. Use with caution.
	controlplane-trust: "disabled"

The comment and validation should be added to avoid confusion.

[nak3]

ref knative/serving#13968

[ReToCode]

I think this will be resolved with knative/serving#14368, right? The idea is, that we'll only add options if we are really supporting them.

[nak3]

Yes, that's right. Closing as knative/serving#14368 can be tracked.