Phase 1A security register items 1 and 2, landed ahead of the command
fan-out because they are independently testable and the fan-out is the
first caller of TryGetPsk.
Item 1 — known-cluster gate. MeshPskProvider gains SetKnownClusters, an
atomic whole-set swap consulted by TryGetPsk BEFORE the config map and
before the secret store. A cluster id outside the set is refused in O(1)
with no store read and no audit write, which closes two things at once:
the pre-auth store/audit flood an unauthenticated caller could drive with
a forged x-otopcua-cluster header, and the timing oracle that defeated
CentralCommandAuthInterceptor's uniform denial text (unknown clusters are
never cached, so they paid a store read on every probe while known ones
answered from memory). Empty or never-published leaves the gate inactive
— central publishes the set from its DB contact refresh, and 'the DB told
me nothing' must not become a fleet-wide authentication outage during
admin boot.
Item 2 — bool Matches(clusterId, presented) on IMeshPskProvider, with
FixedTimeEquals inside the provider. CentralCommandAuthInterceptor now
calls it and never holds key material; its two provider-side denial logs
collapse into one (the provider answers both as false) and the operator
hint is restated there.
No production caller publishes a cluster set yet, so behaviour is
unchanged until the fan-out commit wires the contact refresh.
ControlPlane.Tests 190 -> 205, Host.Tests 91 -> 92.
Joseph Doherty
14d21496fe