Build the on-host agent that pairs with fleet-hostapi and feeds the
fleet-manager control plane (TODO #14 "STILL TO BUILD (a)"). Nothing on the
workstation talked to the manager before this; Monitor + InfluxDB stayed empty.
Scope: telemetry only. The agent reuses the host TPM identity for mTLS (read-only
tpmkey.LoadSigner at 0x81000100 + cert from NV 0x01800100; the private key never
leaves the TPM), opens the long-lived FleetAgent.Session bidi stream, sends Hello
+ periodic HealthSnapshot (load/cpu/temp/mem/tmpfs/nvme/auth/selinux/chrony/kiosk,
probed read-only from /proc+/sys plus hostapi facts), and LOGS but does not act on
the DesiredState/Command it receives. Reconcile actuators (kiosk URL, reboot,
drain) are deferred until the telemetry half is bench-verified.
- files/agent/: new module (go-tpm + grpc), static CGO_ENABLED=0 like enrol/hostapi.
Copies the enrol tpmkey (+ read-only LoadSigner) and the generated fleet.agent.v1
proto so it stays self-contained without importing the initramfs enrol module.
- files/agent/simtest/: proves the TPM-signed cert completes a real mTLS client-auth
handshake (RequireAndVerifyClientCert) against the go-tpm software simulator.
- files/etc/fleet-agent/agent.env: fleet-generic config (manager DNS name, fleet CA
reused from radius-ca.pem, TPM handle/nvindex, interval). No per-host state.
- fleet-agent.service: hardened unit (tss group for /dev/tpmrm0, INET egress).
- CI builds fleet-agent out-of-VM + runs vet/test + the simulator handshake test.
- Packer: enable_agent flag (default on) + 2b-agent provisioner + fapolicyd trust.
Post-switch-root only, so no dracut/initramfs changes.
- docs: TODO #14 + fleet-management-design as-built updated.
Requires the host already enrolled (broker approve births the inventory row) —
else the manager returns PermissionDenied, the correct "not enrolled yet" signal.
Complete the deployment story for the server-side control plane:
- docker-compose.yml: private InfluxDB (published to loopback only) + a
host-networked fleet-manager (reaches the loopback enrol-broker on
127.0.0.1:9443 and binds a routable gRPC agent listener, like the broker).
- .env.example: RP origin (diskless-server.bitasylum.org), Influx token/DB
password, cert/PKI paths; the Influx token wires influxdb + manager with
one value.
- server-pki.sh: issue the agent-plane server cert from the fleet CA (step)
and stage the fleet root as the client-verify CA.
- DEPLOY.md: end-to-end runbook — three-cert PKI (fleet-CA agent cert, broker
admin-client cert, Let's Encrypt DNS-01 UI cert), register-admin passkey
bootstrap, compose up, hardware-free smoke test, backups.
- .dockerignore: keep host node_modules/dist/pki/secrets out of the build
context so the embedded SPA is the one built in-image.
- .gitignore: never commit .env / issued PKI / data.
Design docs marked as-built: fleet-management-design.md as-built note
(resolved forks — gRPC bidi transport, InfluxDB metrics, SPA graphs, passkey
admin auth, broker fold-in "alongside"); tpm-enrolment-design.md (broker
fold-in + agent transport fork resolved); TODO.md #14 → partly built, with
the on-host agent + per-host boot-version assignment (#6) called out as the
remaining work.
The Dell 820 kept "finding a cert" and bypassing enrolment despite repeated BIOS
TPM clears. tpm2_nvreadpublic revealed 0x01800001 on that hardware is a FIRMWARE
platform index (platformcreate|policydelete|writelocked, 70 bytes — not our
cert; siblings at 0x01800003/4 + 0x01810000). platformcreate survives TPM2_Clear
and policydelete needs the platform's secret policy, so it's permanent and
unusable by us — the blind check false-positived on it, and enrolment could
never write there anyway. Same class of bug as the EK-handle collision.
Move the NV cert index default 0x01800001 -> 0x01800100 (free on the 820, owner
range, overridable via rd.dot1x.nvindex): cmdline (extract-artifacts.sh),
fleet-enrol -nvindex, the dracut hooks, bench scripts, CLAUDE.md invariant #1,
and design/SSP docs. The signing-key handle (0x81000100) is unchanged.
Harden WriteNVCert: refuse a platformcreate index with a clear "pick a free
owner index via rd.dot1x.nvindex" error instead of a confusing undefine
failure. Regression simtest/TestWriteNVCertRefusesPlatformIndex; NV roundtrip +
ReadNVCert tests moved to 0x01800100. All go tests + packer validate pass.
Bench (Proxmox vTPM, host cygnus-cruiser-99) confirmed via tpm2_readpublic that
0x81010001 — the handle our design used for the fleet signing key — is the
TCG-standard RSA Endorsement Key slot: the object there is the swtpm-provisioned
EK (restricted|decrypt|adminwithpolicy, RSA-2048/AES128CFB, canonical EK
authPolicy 837197…, EK cert at NV 0x1c00002). Most firmware/swtpm TPMs occupy
that slot, so EnsureKey could never create our key there — it errored reading
the EK as ECC and enrolment died before the CSR/POST.
Move the fleet signing key to 0x81000100, a non-reserved owner persistent
handle (clear of EK 0x81010001/2 and SRK 0x81000001/2). Threaded through:
- fleet-enrol -handle default + new rd.dot1x.handle= cmdline knob (baked by
extract-artifacts.sh, overridable via SMBIOS)
- files/etc/dot1x/wpa_supplicant-dot1x.conf private_key handle
- the dracut hook, bench tpm-provision.sh / tpm-selftest.sh
- CLAUDE.md invariant #1 + design/SSP docs + TODO #11
NV index 0x01800001 (owner range) is unchanged.
EnsureKey hardening: refuse to evict any restricted-decrypt object (EK/SRK) as
a safety net — never clobber the TPM endorsement/storage identity (also
protects the future EK/AK attestation path). Still self-heals a genuine stale
signing key. New regression TestEnsureKeyRefusesToEvictProtectedKey; the
stale-key regression and handle constants moved to 0x81000100.
Design note records the IDevID (0x81020001) option for the later EK/AK
attestation work. Follow-up items logged: content-aware NV presence check
(verify the cert chains to the fleet CA, so leftover/foreign NV can't suppress
enrolment) and a de-enrol/TPM-reset procedure.
Audiobuzz