@gramota/sd-jwt

IETF SD-JWT-VC primitives — parse, issue, hash-binding verify, key-binding (KB-JWT) build / verify. Tight low-level layer; most consumers should reach for @gramota/issuer, @gramota/holder, or @gramota/verifier instead.

Part of Gramota — the TypeScript SDK for the EU Digital Identity Wallet (EUDIW).

Install

pnpm add @gramota/sd-jwt
# or: npm install @gramota/sd-jwt
# or: yarn add @gramota/sd-jwt

Quick example — parse + hash-binding verify

import { parseSdJwt, verifyHashBinding } from "@gramota/sd-jwt";

const parsed = parseSdJwt(presentationToken);
const verified = verifyHashBinding(parsed);
console.log(verified.disclosed);          // user claims
console.log(verified.unmatchedDisclosures); // expected []

Quick example — KB-JWT (holder presentation binding)

import { buildKeyBindingJwt, computeSdHash } from "@gramota/sd-jwt";

const sdHash = computeSdHash(presentationPrefix); // <issuer-jws>~<d1>~...~<dN>~
const kbJwt = await buildKeyBindingJwt({
  signer,                       // holder's @gramota/jose Signer
  aud: "https://verifier.example",
  nonce: "n-from-verifier",
  sdHash,
});
const fullPresentation = `${presentationPrefix}${kbJwt}`;

What's inside

• parseSdJwt — split <issuer-jws>~<d1>~...~<dN>~<kb-jwt?> and decode parts
• issueSdJwt — produce a fresh SD-JWT from claims + a list of selectively-disclosable paths
• verifyHashBinding — match disclosures to _sd digests; reject forgeries
• buildKeyBindingJwt / verifyKeyBinding — IETF SD-JWT §4.3 holder binding
• computeSdHash — RFC-aligned sd_hash claim used in KB-JWT
• One error class — SdJwtError — with codes namespaced by operation (sd_jwt.parse.*, sd_jwt.verify.*, sd_jwt.kb.*, sd_jwt.issue.*)

For the high-level Verifier / Issuer / Holder API, see the main repo.

License

Apache 2.0