The conntrack reconciler maintains the consistency between the
conntrack table on each node and the desired state of Kubernetes UDP services.
A valid entry matches a service's ClusterIP, LoadBalancerIP, or ExternalIP and Service port,
or any ip matching a NodePort, and has a reverse source IP matching an active endpoint for
that service. Other entries are deleted.
Services without endpoints and traffic not handled by kube-proxy are ignored
Co-authored-by: Daman Arora <aroradaman@gmail.com>
Add an interface between CleanStaleEntries and the lower-level
conntrack helpers (ClearEntriesForIP, etc), and a fake implementation
of that interface, so that we can explicitly test CleanStaleEntries's
logic.
Remove some comments from conntrack.go that were explaining the
functions' callers rather than explaining the functions themselves
(and which were redundant with other comments in the callers anyway).
