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Lazarus Pascal

XML Signature Multiple External References

See more XML Digital Signatures Examples

Demonstrates how to add multiple external references to an XML digital signature.

Chilkat Lazarus Pascal Downloads

Lazarus Pascal
program ChilkatDemo;

// Demonstrates using the Chilkat Pascal wrapper via the C bridge DLL.
// Builds as a console application under Lazarus (FPC) or Delphi.

{$IFDEF FPC}
  {$MODE DELPHI}
{$ENDIF}
{$APPTYPE CONSOLE}

uses
  {$IFDEF UNIX}
  cthreads,
  {$ENDIF}
  SysUtils,
  CkDllLoader,
  Chilkat.XmlDSigGen,
  Chilkat.XmlDSig,
  Chilkat.StringBuilder,
  Chilkat.BinData,
  Chilkat.Cert,
  Chilkat.Http,
  Chilkat.Xml;

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

procedure RunDemo;
var
  success: Boolean;
  gen: TXmlDSigGen;
  object1: TXml;
  http: THttp;
  bd: TBinData;
  url: string;
  cert: TCert;
  sbXml: TStringBuilder;
  verifier: TXmlDSig;
  verified: Boolean;

begin
  success := False;

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

  //  This example creates the following signed XML with multiple external references:

  //  <?xml version="1.0" encoding="UTF-8"?>
  //  <ds:Signature xmlns:ds="http://www.w3.org/2000/09/xmldsig#" Id="xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4">
  //      <ds:SignedInfo>
  //          <ds:CanonicalizationMethod Algorithm="http://www.w3.org/TR/2001/REC-xml-c14n-20010315"/>
  //          <ds:SignatureMethod Algorithm="http://www.w3.org/2001/04/xmldsig-more#rsa-sha256"/>
  //          <ds:Reference Id="xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref0" URI="https://isus.ezdrowie.gov.pl/fhir/Patient/123/_history/456">
  //              <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>
  //              <ds:DigestValue>...</ds:DigestValue>
  //          </ds:Reference>
  //          <ds:Reference Id="xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref1" URI="https://isus.ezdrowie.gov.pl/fhir/Encounter/124/_history/22">
  //              <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>
  //              <ds:DigestValue>...</ds:DigestValue>
  //          </ds:Reference>
  //          <ds:Reference Id="xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref2" URI="https://isus.ezdrowie.gov.pl/fhir/Condition/125/_history/1">
  //              <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>
  //              <ds:DigestValue>...</ds:DigestValue>
  //          </ds:Reference>
  //          <ds:Reference Id="xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref3" URI="https://isus.ezdrowie.gov.pl/fhir/Procedure/126/_history/1">
  //              <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>
  //              <ds:DigestValue>...</ds:DigestValue>
  //          </ds:Reference>
  //          <ds:Reference Type="http://uri.etsi.org/01903#SignedProperties" URI="#xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-signedprops">
  //              <ds:Transforms>
  //                  <ds:Transform Algorithm="http://www.w3.org/TR/2001/REC-xml-c14n-20010315"/>
  //              </ds:Transforms>
  //              <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>
  //              <ds:DigestValue>...</ds:DigestValue>
  //          </ds:Reference>
  //      </ds:SignedInfo>
  //      <ds:SignatureValue Id="xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-sigvalue">...</ds:SignatureValue>
  //      <ds:KeyInfo>
  //          <ds:X509Data>
  //              <ds:X509Certificate>...</ds:X509Certificate>
  //              <ds:X509SubjectName>...</ds:X509SubjectName>
  //              <ds:X509IssuerSerial>
  //                  <ds:X509IssuerName>...</ds:X509IssuerName>
  //                  <ds:X509SerialNumber>...</ds:X509SerialNumber>
  //              </ds:X509IssuerSerial>
  //          </ds:X509Data>
  //      </ds:KeyInfo>
  //      <ds:Object>
  //          <xades:QualifyingProperties xmlns:xades="http://uri.etsi.org/01903/v1.3.2#" xmlns:xades141="http://uri.etsi.org/01903/v1.4.1#" Target="#xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4">
  //              <xades:SignedProperties Id="xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-signedprops">
  //                  <xades:SignedSignatureProperties>
  //                      <xades:SigningTime>2021-06-02T07:10:13.306+02:00</xades:SigningTime>
  //                      <xades:SigningCertificate>
  //                          <xades:Cert>
  //                              <xades:CertDigest>
  //                                  <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>
  //                                  <ds:DigestValue>...</ds:DigestValue>
  //                              </xades:CertDigest>
  //                              <xades:IssuerSerial>
  //                                  <ds:X509IssuerName>...</ds:X509IssuerName>
  //                                  <ds:X509SerialNumber>...</ds:X509SerialNumber>
  //                              </xades:IssuerSerial>
  //                          </xades:Cert>
  //                          <xades:Cert>
  //                              <xades:CertDigest>
  //                                  <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>
  //                                  <ds:DigestValue>...</ds:DigestValue>
  //                              </xades:CertDigest>
  //                              <xades:IssuerSerial>
  //                                  <ds:X509IssuerName>...</ds:X509IssuerName>
  //                                  <ds:X509SerialNumber>...</ds:X509SerialNumber>
  //                              </xades:IssuerSerial>
  //                          </xades:Cert>
  //                          <xades:Cert>
  //                              <xades:CertDigest>
  //                                  <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>
  //                                  <ds:DigestValue>...</ds:DigestValue>
  //                              </xades:CertDigest>
  //                              <xades:IssuerSerial>
  //                                  <ds:X509IssuerName>...</ds:X509IssuerName>
  //                                  <ds:X509SerialNumber>...</ds:X509SerialNumber>
  //                              </xades:IssuerSerial>
  //                          </xades:Cert>
  //                      </xades:SigningCertificate>
  //                  </xades:SignedSignatureProperties>
  //              </xades:SignedProperties>
  //          </xades:QualifyingProperties>
  //      </ds:Object>
  //  </ds:Signature>
  //  

  success := True;
  gen := TXmlDSigGen.Create;

  gen.SigLocation := '';
  gen.SigLocationMod := 0;
  //  Note: ID's simply need to be unique values in the signed XML document.  They don't necessarily need to be GUID/UUID formatted.
  gen.SigId := 'xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4';
  gen.SigNamespacePrefix := 'ds';
  gen.SigNamespaceUri := 'http://www.w3.org/2000/09/xmldsig#';
  gen.SigValueId := 'xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-sigvalue';
  gen.SignedInfoCanonAlg := 'C14N';
  gen.SignedInfoDigestMethod := 'sha256';

  //  Create an Object to be added to the Signature.
  object1 := TXml.Create;
  object1.Tag := 'xades:QualifyingProperties';
  object1.AddAttribute('xmlns:xades','http://uri.etsi.org/01903/v1.3.2#');
  object1.AddAttribute('xmlns:xades141','http://uri.etsi.org/01903/v1.4.1#');
  object1.AddAttribute('Target','#xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4');
  object1.UpdateAttrAt('xades:SignedProperties',True,'Id','xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-signedprops');
  object1.UpdateChildContent('xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningTime','TO BE GENERATED BY CHILKAT');
  //  This assumes there are 3 certs in the certificate chain:  The signing certificate, an intermediate root, and the root CA.
  //  Remove the lines with "Cert[2]" if there is no intermediate root...
  object1.UpdateAttrAt('xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningCertificateV2|xades:Cert|xades:CertDigest|ds:DigestMethod',True,'Algorithm','http://www.w3.org/2001/04/xmlenc#sha256');
  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');

  gen.AddObject('',object1.GetXml(),'','');

  http := THttp.Create;
  bd := TBinData.Create;

  url := 'https://isus.ezdrowie.gov.pl/fhir/Patient/123/_history/456';
  success := http.QuickGetBd(url,bd);
  if (success <> True) then
    begin
      WriteLn(http.LastErrorText);
      Exit;
    end;

  //  -------- Reference 1 --------
  gen.AddExternalBinaryRef(url,bd,'sha256','');
  gen.SetRefIdAttr(url,'xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref0');

  //  -------- Reference 2 --------
  bd.Clear();
  url := 'https://isus.ezdrowie.gov.pl/fhir/Encounter/789/_history/1';
  success := http.QuickGetBd(url,bd);
  if (success <> True) then
    begin
      WriteLn(http.LastErrorText);
      Exit;
    end;
  gen.AddExternalBinaryRef(url,bd,'sha256','');
  gen.SetRefIdAttr(url,'xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref1');

  //  -------- Reference 3 --------
  bd.Clear();
  url := 'https://isus.ezdrowie.gov.pl/fhir/Condition/123456/_history/1';
  success := http.QuickGetBd(url,bd);
  if (success <> True) then
    begin
      WriteLn(http.LastErrorText);
      Exit;
    end;
  gen.AddExternalBinaryRef(url,bd,'sha256','');
  gen.SetRefIdAttr(url,'xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref2');

  //  -------- Reference 4 --------
  bd.Clear();
  url := 'https://isus.ezdrowie.gov.pl/fhir/Procedure/123456/_history/1';
  success := http.QuickGetBd(url,bd);
  if (success <> True) then
    begin
      WriteLn(http.LastErrorText);
      Exit;
    end;
  gen.AddExternalBinaryRef(url,bd,'sha256','');
  gen.SetRefIdAttr(url,'xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref3');

  //  -------- Reference 5 --------
  gen.AddObjectRef('xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-signedprops','sha256','C14N','','http://uri.etsi.org/01903#SignedProperties');

  //  Provide a certificate + private key. (PFX password is test123)
  cert := TCert.Create;
  success := cert.LoadPfxFile('qa_data/pfx/cert_test123.pfx','test123');
  if (success <> True) then
    begin
      WriteLn(cert.LastErrorText);
      Exit;
    end;
  gen.SetX509Cert(cert,True);

  gen.KeyInfoType := 'X509Data';
  gen.X509Type := 'IssuerSerial,SubjectName,Certificate';

  //  This will be an enveloping signature where the Signature element
  //  is the XML document root, the signed data is contained within Object
  //  tag(s) within the Signature.
  //  Therefore, pass an empty sbXml to CreateXmlDsigSb.
  sbXml := TStringBuilder.Create;

  gen.Behaviors := 'IndentedSignature';

  //  Sign the XML...
  success := gen.CreateXmlDSigSb(sbXml);
  if (success <> True) then
    begin
      WriteLn(gen.LastErrorText);
      Exit;
    end;
  //  -----------------------------------------------

  //  Save the signed XML to a file.
  success := sbXml.WriteFile('qa_output/signedXml.xml','utf-8',False);

  WriteLn(sbXml.GetAsString());

  //  ----------------------------------------
  //  Verify the signature we just produced...
  verifier := TXmlDSig.Create;
  success := verifier.LoadSignatureSb(sbXml);
  if (success <> True) then
    begin
      WriteLn(verifier.LastErrorText);
      Exit;
    end;

  verified := verifier.VerifySignature(True);
  if (verified <> True) then
    begin
      WriteLn(verifier.LastErrorText);
      Exit;
    end;
  WriteLn('This signature was successfully verified.');


  gen.Free;
  object1.Free;
  http.Free;
  bd.Free;
  cert.Free;
  sbXml.Free;
  verifier.Free;

end;

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

begin

  try
    RunDemo;
  except
    on E: Exception do
      WriteLn('Unhandled exception: ', E.ClassName, ': ', E.Message);
  end;

  WriteLn;
  {$IFDEF MSWINDOWS}
  WriteLn('Press Enter to exit...');
  ReadLn;
  {$ENDIF}
end.