Genuineness guide

The Cryptnox genuineness / attestation applet (RID A0000010, AID A000001000024701) carries an on-card EC device key and a device certificate that chains to the Cryptnox PKI. It lets a host prove a card is genuine Cryptnox hardware without any shared secret. For the condensed version, see Quick start: prove a card is genuine.

The applet is contact-only — it does not answer over a contactless reader (SELECT returns 6A82 there) — and all genuine commands are read-only: the applet is inspected, never provisioned, by this tool.

What is checked — and what deliberately is not

There is more than one way to test a Cryptnox card’s genuineness; the methods differ in what secret the verifier needs. This tool performs the two checks that need no secret key material:

  • Proof of possession (live). The host sends a fresh random nonce and the card signs it with its device key (ATTEST); the signature is verified against the on-card leaf certificate’s public key. Because the nonce is random per run, a copied certificate or a replayed signature cannot pass — the card must physically hold the device private key now.

  • Certificate chain. leaf -> Genuineness CA -> … -> pinned Cryptnox root, validated (name chaining, signatures, validity windows, CA constraints) and anchored on the pinned trust store. A root is trusted only because it is pinned — never because it appears in a chain read off the card.

The verdict is GENUINE only when both pass; proof of possession alone yields NOT proven.

It deliberately does not attempt the ISD or PIV-SSD key checks: those verify per-card, HSM/KDF-derived secret keys that this tool has no access to. Their absence is stated in the output, never hidden.

Trust anchors

The Cryptnox production root ships bundled, together with the genuineness CA that sits under it, so production cards anchor without extra setup. Where no pinned root covers the chain, the chain step reports “cannot verify” and the verdict is NOT proven even though proof of possession passes — the tool never silently treats an unanchored chain as genuine.

Add anchors with --anchors DIR (a directory of CA PEMs) or the CRYPTNOX_TRUST_DIR environment variable; both extend the bundled set rather than replacing it.

Development cards

A dev card chains to a throwaway dev root and can never pass as genuine Cryptnox hardware; genuine verify --anchors <dev-ca-dir> verifies it against the dev PKI for testing the flow only.

Inspection without the proof

info, doctor and the report commands surface the applet’s state (present / personalized / not present) without running the proof; report genuine emits it as a secret-safe JSON snapshot (see JSON output). Only genuine verify produces a verdict.

Next steps