covid-certificate/lib/parse/readCertificate.js

Parse and verify a european digital covid certificate (dcc)

"use strict";
var __importDefault = (this && this.__importDefault) || function (mod) {
    return (mod && mod.__esModule) ? mod : { "default": mod };
};
Object.defineProperty(exports, "__esModule", { value: true });
exports.readCertificate = void 0;
const SingleSignedMessage_1 = require("../cose/SingleSignedMessage");
const pako_1 = require("pako");
const base45_1 = require("./base45");
const strip_header_1 = require("./strip_header");
const cbor_1 = require("cbor");
const ChainValidator_1 = __importDefault(require("../validate/ChainValidator"));
const IsCoseSingleSignedMessageValidator_1 = __importDefault(require("../validate/cbor/IsCoseSingleSignedMessageValidator"));
/**
 * Parse a certificate string into a COSE single signed message
 *
 * @example
 * Here is an example:
 * ```
 * const cert = readCertificate("HC1:data_from_QR_scanner");
 * ```
 *
 * @param certificate - The base45 encoded, zlib deflated, CBor encoded string. Normally one can obtain
 * such string by scanning a QR-code
 */
const readCertificate = (certificate) => {
    const coseMessage = (0, pako_1.inflate)((0, base45_1.decode)((0, strip_header_1.strip_header)(certificate)));
    const data = (0, cbor_1.decode)(coseMessage);
    // Create validator
    const cborValidator = new ChainValidator_1.default([
        new IsCoseSingleSignedMessageValidator_1.default(),
    ]);
    // Validate data
    const validationResult = cborValidator.validate(data);
    if (!validationResult.isValid()) {
        throw new Error("Given certificate string not valid: " + validationResult.getMessage());
    }
    // Create single signed cose message
    const [protectedHeaders, unprotectedHeaders, payload, signature] = data.value;
    const message = new SingleSignedMessage_1.SingleSignedMessage();
    message.setProtectedHeaders(protectedHeaders);
    message.setUnprotectedHeaders(unprotectedHeaders);
    message.setPayload(payload);
    message.setSignature(signature);
    return message;
};
exports.readCertificate = readCertificate;