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Dart

XML-DSig Add Object Reference with Transforms Specified Explicitly

Demonstrates how to use the new AddObjectRef2 method to explicitly specify the XML Transforms fragment.

Chilkat Dart Downloads

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.

  // Build the following XML to be signed:

  // <?xml version="1.0" encoding="utf-8"?>
  // <InitUpload xmlns="http://e-dokumenty.mf.gov.pl">
  //     <DocumentType>JPK</DocumentType>
  //     <Version>01.02.01.20160617</Version>
  //     <EncryptionKey algorithm="RSA" encoding="Base64" mode="ECB" padding="PKCS#1">xxxx</EncryptionKey>
  //     <DocumentList>
  //         <Document>
  //             <FormCode schemaVersion="1-1" systemCode="JPK_VAT (3)">JPK_VAT</FormCode>
  //             <FileName>JPK_VAT_3_v1-1_20181201.xml</FileName>
  //             <ContentLength>8736</ContentLength>
  //             <HashValue algorithm="SHA-256" encoding="Base64">JEDI1pItwh6dj/Xx1uts/x61qnjZ4DLHpkZMhmf1oKQ=</HashValue>
  //             <FileSignatureList filesNumber="1">
  //                 <Packaging>
  //                     <SplitZip mode="zip" type="split"/>
  //                 </Packaging>
  //                 <Encryption>
  //                     <AES block="16" mode="CBC" padding="PKCS#7" size="256">
  //                         <IV bytes="16" encoding="Base64">z64oN9zXHt1+S3XACRSCYw==</IV>
  //                     </AES>
  //                 </Encryption>
  //                 <FileSignature>
  //                     <OrdinalNumber>1</OrdinalNumber>
  //                     <FileName>JPK_VAT_3_v1-1_20181201-000.xml.zip.aes</FileName>
  //                     <ContentLength>16</ContentLength>
  //                     <HashValue algorithm="MD5" encoding="Base64">5MX0q1935fvMjLFV7E1yDw==</HashValue>
  //                 </FileSignature>
  //             </FileSignatureList>
  //         </Document>
  //     </DocumentList>
  // </InitUpload>

  // Use this online tool to generate code from sample XML: 
  // Generate Code to Create XML

  final xmlToSign = CkXml();
  xmlToSign.tag = 'InitUpload';
  xmlToSign.addAttribute('xmlns', 'http://e-dokumenty.mf.gov.pl');
  xmlToSign.updateChildContent('DocumentType', 'JPK');
  xmlToSign.updateChildContent('Version', '01.02.01.20160617');
  xmlToSign.updateAttrAt('EncryptionKey', true, 'algorithm', 'RSA');
  xmlToSign.updateAttrAt('EncryptionKey', true, 'encoding', 'Base64');
  xmlToSign.updateAttrAt('EncryptionKey', true, 'mode', 'ECB');
  xmlToSign.updateAttrAt('EncryptionKey', true, 'padding', 'PKCS#1');
  xmlToSign.updateChildContent('EncryptionKey', 'xxxx');
  xmlToSign.updateAttrAt('DocumentList|Document|FormCode', true, 'schemaVersion', '1-1');
  xmlToSign.updateAttrAt('DocumentList|Document|FormCode', true, 'systemCode', 'JPK_VAT (3)');
  xmlToSign.updateChildContent('DocumentList|Document|FormCode', 'JPK_VAT');
  xmlToSign.updateChildContent('DocumentList|Document|FileName', 'JPK_VAT_3_v1-1_20181201.xml');
  xmlToSign.updateChildContent('DocumentList|Document|ContentLength', '8736');
  xmlToSign.updateAttrAt('DocumentList|Document|HashValue', true, 'algorithm', 'SHA-256');
  xmlToSign.updateAttrAt('DocumentList|Document|HashValue', true, 'encoding', 'Base64');
  xmlToSign.updateChildContent('DocumentList|Document|HashValue', 'JEDI1pItwh6dj/Xx1uts/x61qnjZ4DLHpkZMhmf1oKQ=');
  xmlToSign.updateAttrAt('DocumentList|Document|FileSignatureList', true, 'filesNumber', '1');
  xmlToSign.updateAttrAt('DocumentList|Document|FileSignatureList|Packaging|SplitZip', true, 'mode', 'zip');
  xmlToSign.updateAttrAt('DocumentList|Document|FileSignatureList|Packaging|SplitZip', true, 'type', 'split');
  xmlToSign.updateAttrAt('DocumentList|Document|FileSignatureList|Encryption|AES', true, 'block', '16');
  xmlToSign.updateAttrAt('DocumentList|Document|FileSignatureList|Encryption|AES', true, 'mode', 'CBC');
  xmlToSign.updateAttrAt('DocumentList|Document|FileSignatureList|Encryption|AES', true, 'padding', 'PKCS#7');
  xmlToSign.updateAttrAt('DocumentList|Document|FileSignatureList|Encryption|AES', true, 'size', '256');
  xmlToSign.updateAttrAt('DocumentList|Document|FileSignatureList|Encryption|AES|IV', true, 'bytes', '16');
  xmlToSign.updateAttrAt('DocumentList|Document|FileSignatureList|Encryption|AES|IV', true, 'encoding', 'Base64');
  xmlToSign.updateChildContent('DocumentList|Document|FileSignatureList|Encryption|AES|IV', 'z64oN9zXHt1+S3XACRSCYw==');
  xmlToSign.updateChildContent('DocumentList|Document|FileSignatureList|FileSignature|OrdinalNumber', '1');
  xmlToSign.updateChildContent('DocumentList|Document|FileSignatureList|FileSignature|FileName', 'JPK_VAT_3_v1-1_20181201-000.xml.zip.aes');
  xmlToSign.updateChildContent('DocumentList|Document|FileSignatureList|FileSignature|ContentLength', '16');
  xmlToSign.updateAttrAt('DocumentList|Document|FileSignatureList|FileSignature|HashValue', true, 'algorithm', 'MD5');
  xmlToSign.updateAttrAt('DocumentList|Document|FileSignatureList|FileSignature|HashValue', true, 'encoding', 'Base64');
  xmlToSign.updateChildContent('DocumentList|Document|FileSignatureList|FileSignature|HashValue', '5MX0q1935fvMjLFV7E1yDw==');

  final gen = CkXmlDSigGen();

  gen.sigLocation = 'InitUpload';
  gen.sigLocationMod = 0;
  gen.sigId = 'id-1234';
  gen.sigNamespacePrefix = 'ds';
  gen.sigNamespaceUri = 'http://www.w3.org/2000/09/xmldsig#';
  gen.signedInfoCanonAlg = 'EXCL_C14N';
  gen.signedInfoDigestMethod = 'sha256';

  // Create an Object to be added to the Signature.

  // <xades:QualifyingProperties Target="#id-1234" xmlns:xades="http://uri.etsi.org/01903/v1.3.2#">
  //     <xades:SignedProperties Id="xades-id-1234">
  //         <xades:SignedSignatureProperties>
  //             <xades:SigningTime>TO BE GENERATED BY CHILKAT</xades:SigningTime>
  //             <xades:SigningCertificate>
  //                 <xades:Cert>
  //                     <xades:CertDigest>
  //                         <ds:DigestMethod Algorithm="http://www.w3.org/2000/09/xmldsig#sha1"/>
  //                         <ds:DigestValue>TO BE GENERATED BY CHILKAT</ds:DigestValue>
  //                     </xades:CertDigest>
  //                     <xades:IssuerSerial>
  //                         <ds:X509IssuerName>TO BE GENERATED BY CHILKAT</ds:X509IssuerName>
  //                         <ds:X509SerialNumber>TO BE GENERATED BY CHILKAT</ds:X509SerialNumber>
  //                     </xades:IssuerSerial>
  //                 </xades:Cert>
  //             </xades:SigningCertificate>
  //         </xades:SignedSignatureProperties>
  //         <xades:SignedDataObjectProperties>
  //             <xades:DataObjectFormat ObjectReference="#r-id-1">
  //                 <xades:MimeType>text/xml</xades:MimeType>
  //             </xades:DataObjectFormat>
  //         </xades:SignedDataObjectProperties>
  //     </xades:SignedProperties>
  // </xades:QualifyingProperties>

  final object1 = CkXml();
  object1.tag = 'xades:QualifyingProperties';
  object1.addAttribute('xmlns:xades', 'http://uri.etsi.org/01903/v1.3.2#');
  object1.addAttribute('Target', '#id-1234');
  object1.updateAttrAt('xades:SignedProperties', true, 'Id', 'xades-id-1234');
  // Note: It may be that http://www.w3.org/2001/04/xmlenc#sha256 is needed in the following line instead of http://www.w3.org/2000/09/xmldsig#sha1
  object1.updateChildContent('xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningTime', 'TO BE GENERATED BY CHILKAT');
  object1.updateAttrAt('xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningCertificateV2|xades:Cert|xades:CertDigest|ds:DigestMethod', true, 'Algorithm', 'http://www.w3.org/2000/09/xmldsig#sha1');
  object1.updateChildContent('xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningCertificateV2|xades:Cert|xades:CertDigest|ds:DigestValue', 'TO BE GENERATED BY CHILKAT');
  object1.updateChildContent('xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningCertificateV2|xades:Cert|xades:IssuerSerialV2', 'TO BE GENERATED BY CHILKAT');
  object1.updateAttrAt('xades:SignedProperties|xades:SignedDataObjectProperties|xades:DataObjectFormat', true, 'ObjectReference', '#r-id-1');
  object1.updateChildContent('xades:SignedProperties|xades:SignedDataObjectProperties|xades:DataObjectFormat|xades:MimeType', 'text/xml');

  gen.addObject('', object1.getXml(), '', '');

  // -------- Reference 1 --------
  // Build the following Transforms fragment:

  // <ds:Transforms>
  //     <ds:Transform Algorithm="http://www.w3.org/TR/1999/REC-xpath-19991116">
  //         <ds:XPath>not(ancestor-or-self::ds:Signature)</ds:XPath>
  //     </ds:Transform>
  //     <ds:Transform Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#"/>
  // </ds:Transforms>

  final xml1 = CkXml();
  xml1.tag = 'ds:Transforms';
  xml1.updateAttrAt('ds:Transform', true, 'Algorithm', 'http://www.w3.org/TR/1999/REC-xpath-19991116');
  xml1.updateChildContent('ds:Transform|ds:XPath', 'not(ancestor-or-self::ds:Signature)');
  xml1.updateAttrAt('ds:Transform[1]', true, 'Algorithm', 'http://www.w3.org/2001/10/xml-exc-c14n#');

  gen.addSameDocRef2('', 'sha256', xml1, '');
  gen.setRefIdAttr('', 'r-id-1');

  // -------- Reference 2 --------
  // Build the following Transforms fragment:

  // <ds:Transforms>
  //     <ds:Transform Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#"/>
  // </ds:Transforms>

  final xml2 = CkXml();
  xml2.tag = 'ds:Transforms';
  xml2.updateAttrAt('ds:Transform', true, 'Algorithm', 'http://www.w3.org/2001/10/xml-exc-c14n#');

  gen.addObjectRef2('xades-id-1234', 'sha256', xml2, 'http://uri.etsi.org/01903#SignedProperties');

  // Provide a certificate + private key. (PFX password is test123)
  final cert = CkCert();
  try {
    cert.loadPfxFile('qa_data/pfx/cert_test123.pfx', 'test123');
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  gen.setX509Cert(cert, true);

  gen.keyInfoType = 'X509Data';
  gen.x509Type = 'Certificate';

  // Load XML to be signed...
  final sbXml = CkStringBuilder();
  xmlToSign.getXmlSb(sbXml);

  gen.behaviors = 'IndentedSignature';

  // Sign the XML...
  try {
    gen.createXmlDSigSb(sbXml);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // -----------------------------------------------

  // Save the signed XML to a file.
  sbXml.writeFile('qa_output/signedXml.xml', 'utf-8', false);

  print(sbXml.getAsString());

  // ----------------------------------------
  // Verify the signatures we just produced...
  final verifier = CkXmlDSig();
  try {
    verifier.loadSignatureSb(sbXml);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  final numSigs = verifier.numSignatures;
  var verifyIdx = 0;
  while (verifyIdx < numSigs) {
    verifier.selector = verifyIdx;
    try {
      verifier.verifySignature(true);
    } on ChilkatException catch (e) {
      print(e.lastErrorText);
      return;
    }

    verifyIdx++;
  }

  print('All signatures were successfully verified.');
}