aere-quantum/identity/README.md

Aere Identity

Post-quantum credentials with selective disclosure, bound to the holder's key, with delegation to devices, agents and short-lived session keys, revocation and an issuer status list. Everything verifies offline, by anyone, from the files alone. Node.js 24, no dependencies (node:crypto provides Ed25519 and ML-DSA-65, FIPS 204).

node identity-cli.mjs keygen --out issuer.keys.json
node identity-cli.mjs keygen --out holder.keys.json
node identity-cli.mjs pub --keys holder.keys.json --out holder.pub.json
node identity-cli.mjs issue --issuer-keys issuer.keys.json --holder-pub holder.pub.json --type MemberCredential \
     --claim member=true --claim tier=gold --claim org=Example --disclosable member,tier \
     --status-list urn:example:status:1 --status-index 5 --out cred.json          # give cred.json to the holder only
node identity-cli.mjs status-list --issuer-keys issuer.keys.json --id urn:example:status:1 --revoke 7 --out list.json
node identity-cli.mjs present --cred cred.json --reveal member --presenter-keys holder.keys.json \
     --audience https://shop.example --nonce <the verifier's nonce> --out presentation.json
node identity-cli.mjs verify --presentation presentation.json --audience https://shop.example --nonce <nonce> \
     --trust-issuer <issuer id> --status-list list.json

verify prints one line per check (ok, FAIL, or -- for not judged, with the reason) and VALID or INVALID; it exits 0 on VALID, 1 on INVALID, 2 on a usage error. The claims it returns are the plain ones plus the ones the holder chose to show.

What is signed, and by whom

Signatures are hybrid: Ed25519 and ML-DSA-65 over the same message, and both are required, so a break of either scheme alone forges nothing. Every message is domain-separated by purpose (aere-identity/v1/<purpose>\n + text, purposes credential, presentation, delegation, revocation, status-list, and for the Travel Rule kem-binding, travel-rule, travel-rule-receipt), so a signature made for one purpose is not valid for another over the same text. The signed text is the canonical JSON of the statement (keys sorted), rebuilt by the verifier.

An identity is its keys: aere-id: + the first 20 bytes of SHA-256 over the canonical form of the two public keys (SPKI). A credential or a delegation that names an id not derived from the keys it carries fails.

Selective disclosure works the way SD-JWT does (IETF RFC 9901), in a format of its own: each disclosable claim becomes [salt, name, value], base64url-encoded; the issuer signs only the SHA-256 digests of those encodings (the sd list, sorted, with optional decoy digests so the number of claims is hidden), and the holder shows only the ones it picks. Claims that are not disclosable sit in the clear. This is not SD-JWT: the signatures are hybrid and the encoding is canonical JSON, so SD-JWT wallets do not read it. It is also not a zero-knowledge proof: a shown claim is shown whole, so a birth date shows the date; an issuer that wants "over 18" issues age_over_18: true as its own claim.

A presentation is bound to one verifier: the presenter signs the credential's hash, the hash of the disclosures it shows, the delegation chain, the verifier's audience and nonce, and the time. Without the verifier's own audience and nonce a presentation made for someone else would be accepted, so verify reports those checks as not judged instead of passing them. A nonce is the verifier's to make fresh and to accept once: a verifier that reuses one accepts a replay within the presentation's age limit.

Inputs the verifier fetched and cannot read (a malformed status list or revocation) are ignored and reported, never counted against the credential; a malformed trusted issuer key is the verifier's own error and stops the verification.

Delegation

A holder can let another key present its credentials: a phone, an AI agent, a session key valid for ten minutes.

node identity-cli.mjs delegate --from-keys holder.keys.json --to-pub phone.pub.json --credentials <credential id> \
     --claims member,tier --audiences '*' --valid-minutes 1440 --max-depth 1 --out phone.delegation.json
node identity-cli.mjs delegate --from-keys phone.keys.json --to-pub session.pub.json --parent phone.delegation.json \
     --credentials <credential id> --claims member --audiences https://shop.example --valid-minutes 10 --out session.delegation.json
node identity-cli.mjs present --cred cred.json --reveal member --presenter-keys session.keys.json \
     --delegation phone.delegation.json --delegation session.delegation.json --audience https://shop.example --nonce <nonce> --out p.json
node identity-cli.mjs revoke --keys holder.keys.json --delegation phone.delegation.json --out revocation.json

Each link is signed by whoever gives it, names its parent link by hash, and can only narrow: its scope (which credentials, which disclosable claims, which audiences) is inside the parent's, its window inside the parent's window, its depth below the parent's. The first link is given by the credential's holder, and the presenter must be the last delegate. A link is revoked by a statement signed by whoever gave it or by the holder; it applies once its time has passed on the verifier's clock, and verify takes the revocations it is handed with --revocation (a revocation it was not handed cannot be seen, and the verdict says so).

Status list

The issuer's status list follows W3C Bitstring Status List v1.0: a bitstring (bit 0 is the most significant bit of the first byte), gzip-compressed, signed by the issuer, with a validity window; the credential names the list and its index. A list that is missing, signed by someone else, or outside its window leaves the status not judged, never "not revoked". With several current lists of the issuer, a bit set in any of them means revoked. A list is decompressed with a ceiling at its declared size (at most 2^24 bits).

Time, said exactly

issuedAt, validFrom and validUntil are the issuer's statements; the presentation time is the presenter's, bounded by the verifier's clock (--max-age, default 300 s, both ways); a revocation time is the revoker's. Everything is judged on the verifier's clock. For a time the issuer does not choose, notarize: proofOfCredential and proofOfDelegation (in identity.mjs) build AIP-23 envelopes (identity and authorization kinds of ../proof-kinds) that the Aere Proof API notarizes and that the AIP-23 reference verifier checks.

Compliance without surveillance (conformitate.mjs)

A verifier writes its compliance policy once: which issuers it believes, and which claims it needs (equals, in, notIn, atLeast, present), for example "over 18, not in these jurisdictions, verification level at least 2". checkCompliance judges a presentation against it: the presentation must be valid and bound to the verifier's audience and nonce, the issuer must be one of the policy's, the credential status must be judged, not merely "not known to be revoked" (unless the policy says otherwise), and every rule must hold. The policy's hash is recomputed from its normal form, so a looser policy cannot pass under a strict one's hash.

node identity-cli.mjs comply --presentation p.json --policy policy.json --audience https://exchange.example --nonce <nonce> \
     --status-list list.json --record record.json [--pseudonym-key-file key]

The record (complianceEnvelope) is an AIP-23 compliance envelope that carries no personal data: the policy's hash, the result, the digest of the presentation, and a pseudonym of the holder bound to this verifier. Without --pseudonym-key-file the pseudonym is a SHA-256 over the holder's id and the audience, which anyone who knows both can recompute (it keeps the id out of the record, it does not hide it from them); with a key it is an HMAC only the verifier can recompute. The verifier keeps the record, and can notarize it for a time it does not choose, instead of keeping the data. What this is not: a zero-knowledge proof (a shown claim is shown whole; "over 18" is a claim the issuer made), an AML or sanctions screening (it consults no list), or legal compliance with anything: it says that one presentation met one policy at one time, as judged by the verifier.

Travel Rule between VASPs, post-quantum (travel-rule.mjs)

The originator and beneficiary data of a transfer (an IVMS101 object) sent from the paying VASP to the receiving VASP, readable only by it: a hybrid key encapsulation (X25519 and ML-KEM-768, both secrets required, HKDF-SHA-256, AES-256-GCM), signed by the originator (Ed25519 and ML-DSA-65), bound to the transfer (chain, asset, amount, beneficiary address, transaction) as authenticated data and in the key derivation, and acknowledged with a signed receipt. Each side proves it is a VASP with a presentation of an Aere Identity credential (vasp: true) from a registry the other side trusts, made for the other side, with its status judged.

import { generateKemKeys, bindKemKeys, acceptBeneficiary, sealMessage, openMessage, acknowledge, verifyReceipt, travelRuleRecord } from './travel-rule.mjs';
// beneficiary: its KEM keys, bound to its identity (signed), handed over with a presentation of its VASP credential for the originator
// originator: acceptBeneficiary({ binding, presentation, registries, originatorId, nonce, statusLists }) -> { ok, beneficiary }
//             sealMessage({ from, beneficiary, ivms101, transfer, presentation /* its own, for the beneficiary, nonce = messageId */ })
// beneficiary: openMessage(message, { me, kem, registries, statusLists, seen }) -> { ok, ivms101, transfer } ; acknowledge(...)
// originator: verifyReceipt(receipt, { message, beneficiaryId }) ; travelRuleRecord({ message, receipt, buildProof })

openMessage refuses a message not signed by the originator it names, sealed for another VASP or other keys, older or newer than 300 seconds on its clock, already received, or whose originator is not proven a VASP. The replay store seen is required (a Set, or any object with has and add, that keeps the ids for at least the 300 seconds): without one, openMessage opens nothing, since the same signed and sealed message could otherwise be opened any number of times. travelRuleRecord writes an AIP-23 compliance envelope with no personal data and no amount: a pseudonymous transfer reference, the policy name, the result and a digest of the exchange. What it does not do: validate the IVMS101 schema (it carries the object as given and requires originator and beneficiary), find the beneficiary's VASP from an address (that is a discovery protocol's job), or say that a transfer is lawful.

What it does not do

It does not bind a key to hardware: a device key is a key like any other, and no TPM or secure-enclave attestation is checked here. It does not rotate or recover keys. It does not say who an identity is in the world: the issuer says that, and the verifier chooses which issuers it believes (--trust-issuer). Without --trust-issuer, anyone can issue a credential with their own keys, and the issuer line is reported as not judged. The private key files are written with mode 0600, which Windows does not apply.

Tests

node proba-identity.mjs              # 43: the paths above, and each attack of the adversarial review as its own test
node control-negativ-identity.mjs    # on a copy, each of 46 guards removed -> its own named test turns red
node proba-conformitate.mjs          # 14: compliance policies judged on real presentations, the record without personal data, the command line
node control-negativ-conformitate.mjs   # on a copy, each of 13 guards removed -> its own named test turns red
node proba-travel-rule.mjs           # 19: two VASPs with registry credentials, the whole exchange, and each attack of the review
node control-negativ-travel-rule.mjs    # on a copy, each of 19 guards removed -> its own named test turns red

The envelope test needs the AIP-23 reference verifier (AERE_VERIFY_PROOF=<verify-proof.mjs>); without it that test is reported as not measured and the suite exits 2. No third party has reviewed any of this.