The steady-state host<->manager transport, resolving the design's OPEN FORK to
bespoke gRPC (not OTLP+Wazuh). One long-lived, host-dialed, mTLS bidi stream:
health/metrics up, desired-state/commands down — no polling, real-time control,
still no inbound host port.
- proto/fleet_agent.proto: FleetAgent.Session(stream AgentUp) -> stream ManagerDown.
AgentUp = Hello | HealthSnapshot | CommandResult; ManagerDown = DesiredState |
Command(reboot/drain/resync). int64 unix times (no well-known-type dep).
Generated stubs committed (CI needs no protoc).
- agent.go: gRPC server with mTLS verified by the FLEET CA (the host's reused TPM
identity cert — distinct from the admin plane's admin CA). Identity is the peer
cert SERIAL, taken from the verified cert = inventory key, never self-asserted;
an unenrolled serial is refused (enrolment gates the stream). Per-conn send
channel decouples admin pushes from stream.Send. Stream registry (serial->conn)
with reconnect eviction. On connect + on change, desired-state is pushed live;
inventory stays authoritative so offline hosts reconcile on reconnect. Metrics
go through a MetricsSink seam (no-op now; InfluxDB in ckpt 4).
- main.go: agent plane starts only when its cert/key/CA are set; admin can run
standalone. Lifecycle PUT now live-pushes and reports pushed_live.
Full mTLS integration test (in-process fleet CA + host client cert): initial
desired-state on connect, Hello+snapshot -> inventory + online presence, live
desired-state push, and unenrolled-serial rejection. go build/test/vet/gofmt clean.
Deps (server-side only): google.golang.org/grpc + protobuf.
