How to use the asn1.js-rfc5280.Certificate function in asn1

var ncert = chain[i + 1];
    // The root cert, check if it's trusted:
    if (!ncert || name) {
      if (!name) {
        return false;
      }
      chain.length = 0;
      return true;
    }
    var nder = ncert.toString('hex');
    var npem = KJUR.asn1.ASN1Util.getPEMStringFromHex(nder, 'CERTIFICATE');

    // Get Next Certificate:
    var ndata = new Buffer(nder, 'hex');
    var nc = rfc5280.Certificate.decode(ndata, 'der');

    var npubKey;
    // Get Public Key from next certificate (via KJUR because it's a mess):
    if (sigHashAlg !== 'none') {
      var js = new KJUR.crypto.Signature({
        alg: sigHashAlg + 'withRSA',
        prov: 'cryptojs/jsrsa'
      });
      js.init(npem);
      npubKey = js.pubKey;
    }

    // Get Signature Value from current certificate:
    var data = new Buffer(der, 'hex');
    var c = rfc5280.Certificate.decode(data, 'der');
    var sig = c.signature.data;

var nc = rfc5280.Certificate.decode(ndata, 'der');

    var npubKey;
    // Get Public Key from next certificate (via KJUR because it's a mess):
    if (sigHashAlg !== 'none') {
      var js = new KJUR.crypto.Signature({
        alg: sigHashAlg + 'withRSA',
        prov: 'cryptojs/jsrsa'
      });
      js.init(npem);
      npubKey = js.pubKey;
    }

    // Get Signature Value from current certificate:
    var data = new Buffer(der, 'hex');
    var c = rfc5280.Certificate.decode(data, 'der');
    var sig = c.signature.data;

    // Check Validity of Certificates
    var validityVerified = PaymentProtocol.validateCertTime(c, nc);

    // Check the Issuer matches the Subject of the next certificate:
    var issuerVerified = PaymentProtocol.validateCertIssuer(c, nc);

    var sigVerified;

    // Verify current Certificate signature
    if (sigHashAlg !== 'none') {
      var jsrsaSig = new KJUR.crypto.Signature({
        alg: sigHashAlg + 'withRSA',
        prov: 'cryptojs/jsrsa'
      });

chain.length = 0;
      return true;
    }
    var nder = ncert.toString('hex');

    // Get Public Key from next certificate:
    var ndata = new Buffer(nder, 'hex');
    var nc = rfc5280.Certificate.decode(ndata, 'der');
    var npubKeyAlg = PaymentProtocol.getAlgorithm(
      nc.tbsCertificate.subjectPublicKeyInfo.algorithm.algorithm);
    var npubKey = nc.tbsCertificate.subjectPublicKeyInfo.subjectPublicKey.data;
    npubKey = PaymentProtocol.DERtoPEM(npubKey, npubKeyAlg + ' PUBLIC KEY');

    // Get Signature Value from current certificate:
    var data = new Buffer(der, 'hex');
    var c = rfc5280.Certificate.decode(data, 'der');
    var sig = c.signature.data;

    // Check Validity of Certificates
    var validityVerified = PaymentProtocol.validateCertTime(c, nc);

    // Check the Issuer matches the Subject of the next certificate:
    var issuerVerified = PaymentProtocol.validateCertIssuer(c, nc);

    // Verify current Certificate signature:
    // Get the raw DER TBSCertificate
    // from the DER Certificate:
    var tbs = PaymentProtocol.getTBSCertificate(data, sig);

    var verifier = crypto.createVerify('RSA-' + sigHashAlg);
    verifier.update(tbs);
    var sigVerified = verifier.verify(npubKey, sig);

var ncert = chain[i + 1];

    // The root cert, check if it's trusted:
    if (!ncert || name) {
      if (!name) {
        return false;
      }
      chain.length = 0;
      return true;
    }
    var nder = ncert.toString('hex');

    // Get Public Key from next certificate:
    var ndata = new Buffer(nder, 'hex');
    var nc = rfc5280.Certificate.decode(ndata, 'der');
    var npubKeyAlg = PaymentProtocol.getAlgorithm(
      nc.tbsCertificate.subjectPublicKeyInfo.algorithm.algorithm);
    var npubKey = nc.tbsCertificate.subjectPublicKeyInfo.subjectPublicKey.data;
    npubKey = PaymentProtocol.DERtoPEM(npubKey, npubKeyAlg + ' PUBLIC KEY');

    // Get Signature Value from current certificate:
    var data = new Buffer(der, 'hex');
    var c = rfc5280.Certificate.decode(data, 'der');
    var sig = c.signature.data;

    // Check Validity of Certificates
    var validityVerified = PaymentProtocol.validateCertTime(c, nc);

    // Check the Issuer matches the Subject of the next certificate:
    var issuerVerified = PaymentProtocol.validateCertIssuer(c, nc);

exports.buildCertId = function (cert)
{
  var issuer = cert.issuerCertificate;
  cert = cert.raw;

  try
  {
    cert = rfc5280.Certificate.decode(cert, 'der');
    if (issuer)
    {
      issuer = issuer.raw;
      issuer = rfc5280.Certificate.decode(issuer, 'der');
    }
  }
  catch (e)
  {
    return null; // if we encountered an error during decoding, return null
  }

  var tbsCert = cert.tbsCertificate;
  var tbsIssuer = issuer.tbsCertificate;

  const certID = {
    hashAlgorithm: {

exports.buildCertId = function (cert)
{
  var issuer = cert.issuerCertificate;
  cert = cert.raw;

  try
  {
    cert = rfc5280.Certificate.decode(cert, 'der');
    if (issuer)
    {
      issuer = issuer.raw;
      issuer = rfc5280.Certificate.decode(issuer, 'der');
    }
  }
  catch (e)
  {
    return null; // if we encountered an error during decoding, return null
  }

  var tbsCert = cert.tbsCertificate;
  var tbsIssuer = issuer.tbsCertificate;

  const certID = {
    hashAlgorithm: {
      // algorithm: [ 2, 16, 840, 1, 101, 3, 4, 2, 1 ]  // sha256
      algorithm: [1, 3, 14, 3, 2, 26]  // sha1
    },
    issuerNameHash: sha1(rfc5280.Name.encode(tbsCert.issuer, 'der')),

};

const tbs_der = rfc5280.TBSCertificate.encode(tbs, 'der');

const sign = crypto.createSign(digest);
sign.update(tbs_der);
const signature = sign.sign(private_key);

const cert = {
  tbsCertificate: tbs,
  signatureAlgorithm: { algorithm: sha256WithRSAEncryption, parameters: null_ },
  signature:
  { unused: 0,
    data: signature }
};
const pem = rfc5280.Certificate.encode(cert, 'pem', {label: 'CERTIFICATE'});

fs.writeFileSync('./0-dns-cert.pem', pem + '\n');

var BasicOCSPResponse = asn1.define('BasicOCSPResponse', function() {
  this.seq().obj(
    this.key('tbsResponseData').use(ResponseData),
    this.key('signatureAlgorithm').use(rfc5280.AlgorithmIdentifier),
    this.key('signature').bitstr(),
    this.key('certs').optional().explicit(0).seqof(rfc5280.Certificate)
  );
});
exports.BasicOCSPResponse = BasicOCSPResponse;

exports.IA5Str = IA5Str;

var Null = asn1.define('Null', function() {
  this.null_();
});

exports.SHA256 = [ 2, 16, 840, 1, 101, 3, 4, 2, 1 ];
exports.SHA256RSA = [ 1, 2, 840, 113549, 1, 1, 11 ];
exports.SHA512 = [ 2, 16, 840, 1, 101, 3, 4, 2, 3 ];
exports.SHA512RSA = [ 1, 2, 840, 113549, 1, 1, 13 ];
exports.RSA = [ 1, 2, 840, 113549, 1, 1, 1 ];
exports.COMMONNAME = [ 2, 5, 4, 3 ];
exports.ALTNAME = [ 2, 5, 29, 17 ];

exports.TBSCertificate = rfc5280.TBSCertificate;
exports.Certificate = rfc5280.Certificate;
exports.EMPTY_PARAMETERS = Null.encode(null, 'der');

Agent.prototype.handleOCSPResponse = function handleOCSPResponse(socket,
                                                                 stapling,
                                                                 cb) {
  var cert = socket.ssl.getPeerCertificate(true);
  var issuer = cert.issuerCertificate;

  cert = cert.raw;
  try {
    cert = rfc5280.Certificate.decode(cert, 'der');

    if (issuer) {
      issuer = issuer.raw;
      issuer = rfc5280.Certificate.decode(issuer, 'der');
    }
  } catch (e) {
    return cb(e);
  }

  function onIssuer(err, x509) {
    if (err)
      return cb(err);

    issuer = x509;

    if (stapling) {
      var req = ocsp.request.generate(cert, issuer);
      ocsp.verify({
        request: req,
        response: stapling