No secure element is on-site: event signing runs on the software HMAC
(EVENT_SIGNING_KEY, an env var on the host disk), so the ledger is
tamper-EVIDENT but forgeable by anyone who owns the host. Several pages
overstated it as present-tense "ATECC608-signed / unforgeable"; correct them.
- NEW concepts/hardware-signer-options.md: four options for a non-extractable
signing key (USB HSM / YubiKey / reuse the TPM / plain-dongle trap) + the
recommendation (TPM interim → USB-HSM target; ATECC608 stays for the embedded
ESP32, wrong part for a PC host).
- entities/atecc608.md: UPCOMING-not-present status banner + PC-vs-embedded.
- disk-os-hardening.md: fix the live-USB row (BIOS boot-order password is
load-bearing, not Secure Boot — a signed live USB runs); add a physical-tamper
chain (Dell 7070 CMOS-reset → live-USB → PCR-7 same-signer unseal) + accepted
risks (that unseal, unsigned-initramfs evil-maid, operator-USB read TODO).
- open-questions #6 reframed; standing-decisions / overview / threat-model /
index de-overstated; log query entry.
Claude-Session: https://claude.ai/code/session_01Xcm6ikLgGoCxxHrxtjkk5V