Configuring a user should not configure root's authorized_keys

This bug was originally filed in Launchpad as [LP: #1871879](https://bugs.launchpad.net/cloud-init/+bug/1871879)

Launchpad details

affected_projects = []

assignee = None

assignee_name = None

date_closed = None

date_created = 2020-04-09T16:53:41.587279+00:00

date_fix_committed = None

date_fix_released = None

id = 1871879

importance = wishlist

is_complete = False

lp_url = https://bugs.launchpad.net/cloud-init/+bug/1871879

milestone = None

owner = apollo13

owner_name = Florian Apolloner

private = False

status = triaged

submitter = apollo13

submitter_name = Florian Apolloner

tags = []

duplicates = []

_Launchpad user **Florian Apolloner(apollo13)** wrote on 2020-04-09T16:53:41.587279+00:00_

When `ssh_authorized_keys` is configured in user-data keys are unconditionally copied into /root/.ssh/authorized_keys.

If `disable_root` is set to true it leaks the actual configured username: "Please login as the user XYZ rather than the user root." With `disable_root` set to false you can login.

It would be great if there were a way to actually disable root and not touch it at all. I fully understand that the info message is useful for new users, but it would be great to have a way to leave root alone.