React Native

Load .crl, Convert to XML, Get Revoked Serial Numbers and Dates

See more Certificates Examples

Load a binary .crl file (Certificate Revocation List), converts to XML, and then gets the revoked certificate serial numbers and revocation dates.

Note: This example requires Chilkat v9.5.0.77 or greater.

React Native

import { Asn, BinData, CkDateTime, Xml } from '@chilkat/react-native'

function chilkatExample() {
  // This example requires the Chilkat API to have been previously unlocked.
  // See Global Unlock Sample for sample code.

  // Load a binary .crl file.
  const bdCrl = new BinData();
  try {
    bdCrl.loadFile('qa_data/crl/ca1.crl');
  } catch {
    console.log('Failed to load CRL file.');
    return;
  }

  const asn = new Asn();
  try {
    asn.loadBd(bdCrl);
  } catch {
    console.log(asn.lastErrorText);
    return;
  }

  // Convert ASN.1 to XML and load into xml and re-emit for pretty printing..
  const xml = new Xml();
  xml.loadXml(asn.asnToXml());
  xml.saveXml('qa_output/crl.xml');

  // Use this online tool to generate parsing code from CRL XML: 
  // Generate Parsing Code from XML

  // Here's code to parse the XML.  This code was generated by the above tool,
  // and then we modified it by removing unneeded code and changing some names
  let i = 0;
  const tagPath = '';
  let j = 0;
  let countJ = 0;
  let k = 0;
  let countK = 0;

  let revokedCertSerialHex = '';
  let dateRevoked = '';

  const dt = new CkDateTime();

  i = 0;
  const countI = xml.numChildrenHavingTag('sequence');
  while (i < countI) {
    xml.i = i;

    j = 0;
    countJ = xml.numChildrenHavingTag('sequence[i]|sequence');
    while (j < countJ) {
      xml.j = j;

      k = 0;
      countK = xml.numChildrenHavingTag('sequence[i]|sequence[j]|sequence');
      while (k < countK) {
        xml.k = k;

        // Get the revoked certificate's serial number in uppercase hex.
        revokedCertSerialHex = xml.getChildContent('sequence[i]|sequence[j]|sequence[k]|int');
        console.log(`serial number: ${revokedCertSerialHex}`);

        // Get the date/time revoked.  It will be a string formatted as "YYMMDDhhmmssZ", such as "181023093028Z"
        dateRevoked = xml.getChildContent('sequence[i]|sequence[j]|sequence[k]|utctime');

        // Starting in Chilkat v9.5.0.77, date/time strings formatted as YYMMDDhhmmssZ can be parsed as follows:
        dt.setFromTimestamp(dateRevoked);
        console.log(`date revoked: ${dt.getAsRfc822(false)}`);

        k++;
      }

      j++;
    }

    i++;
  }
}