Dart

Verify XML Digital Signature

See more XML Digital Signatures Examples

Verifies XML signatures in an XML file. Dart

import 'package:chilkat/chilkat.dart';

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

  final sbXml = CkStringBuilder();
  try {
    sbXml.loadFile('qa_data/xml_dsig_verify/csioz_sample.xml', 'utf-8');
  } on ChilkatException {
    print('Failed to load XML file.');
    return;
  }

  final dsig = CkXmlDSig();

  // First load the XML containing the signatures to be verified.
  try {
    dsig.loadSignatureSb(sbXml);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // It's possible that an XML document can contain multiple signatures.
  // Each can be verified as follows:
  var i = 0;
  while (i < dsig.numSignatures) {
    // Select the Nth signature by setting the Selector property.
    dsig.selector = i;

    // The bVerifyReferenceDigests argument determines if we want
    // to also verify each reference digest.  If set to false,
    // then only the SignedInfo part of the Signature is verified.
    final bVerifyReferenceDigests = true;
    var bVerified = true;
    try {
      dsig.verifySignature(bVerifyReferenceDigests);
    } on ChilkatException {
      bVerified = false;
    }
    print('Signature ${i + 1} verified = $bVerified');

    i++;
  }
}