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jsonld-signatures-merkleproof2019

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A jsonld signature implementation to support MerkleProof2019 verification in Verifiable Credential context

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var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) { function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); } return new (P || (P = Promise))(function (resolve, reject) { function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } } function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } } function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); } step((generator = generator.apply(thisArg, _arguments || [])).next()); }); }; import jsonld from 'jsonld'; import sha256 from 'sha256'; import preloadedContexts from '../constants/contexts/preloadedContexts'; import { toUTF8Data } from '../utils/data'; import { isObject } from '../utils/object'; import VerifierError from '../models/VerifierError'; import getText from '../helpers/getText'; export function getUnmappedFields(normalized) { const normalizedArray = normalized.split('\n'); const myRegexp = /<http:\/\/fallback\.org\/(.*)>/; const matches = normalizedArray .map(normalizedString => myRegexp.exec(normalizedString)) .filter(match => match != null); if (matches.length > 0) { const unmappedFields = matches.map(match => match[1]).sort(); // only return name of unmapped key return Array.from(new Set(unmappedFields)); // dedup } return null; } export default function computeLocalHash(document_1) { return __awaiter(this, arguments, void 0, function* (document, targetProof = null, documentLoader = (url) => __awaiter(this, void 0, void 0, function* () { return Promise; })) { // the previous implementation was using a reference of @context, thus always adding @vocab to @context, // thus passing the information down to jsonld regardless of the configuration option. We explicitly do that now, // since we want to make sure unmapped fields are detected. if (!document['@context'].find((context) => isObject(context) && '@vocab' in context)) { document['@context'].push({ '@vocab': 'http://fallback.org/' }); } const theDocument = JSON.parse(JSON.stringify(document)); if (!Array.isArray(theDocument.proof)) { // compute the document as it was signed, so without proof delete theDocument.proof; } else { if (!targetProof) { throw new VerifierError('computeLocalHash', getText('errors', 'noProofSpecified')); } const proofIndex = theDocument.proof.findIndex(proof => proof.proofValue === targetProof.proofValue); theDocument.proof = theDocument.proof.slice(0, proofIndex); } const customLoader = function (url) { return __awaiter(this, void 0, void 0, function* () { if (documentLoader != null) { yield documentLoader(url); } if (url in preloadedContexts) { return { contextUrl: null, document: preloadedContexts[url], documentUrl: url }; } return jsonld.documentLoader(url); }); }; const normalizeArgs = { algorithm: 'URDNA2015', format: 'application/nquads', documentLoader: customLoader, safe: false }; let normalizedDocument; try { normalizedDocument = yield jsonld.normalize(theDocument, normalizeArgs); } catch (e) { console.error(e); throw new VerifierError('computeLocalHash', getText('errors', 'failedJsonLdNormalization')); } const unmappedFields = getUnmappedFields(normalizedDocument); if (unmappedFields) { throw new VerifierError('computeLocalHash', `${getText('errors', 'foundUnmappedFields')}: ${unmappedFields.join(', ')}`); } else { return sha256(toUTF8Data(normalizedDocument)); } }); }