Delphi DLL

Canonicalize XML Fragment

See more XML Digital Signatures Examples

Demonstrates how to canonicalize a fragment of an XML document. The fragment is identified by the element having an Id attribute equal to a specified value. (The Id attribute can have any namespace, and the attribute name is case-insensitive (thus "ID", "Id", "id", etc. match). Delphi DLL

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Http, StringBuilder, XmlDSig;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
http: HCkHttp;
sbXml: HCkStringBuilder;
canon: HCkXmlDSig;
canonVersion: PWideChar;
withComments: Boolean;
prefixList: PWideChar;
url: PWideChar;
xmlCanonFrag: PWideChar;

begin
success := False;

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

http := CkHttp_Create();
sbXml := CkStringBuilder_Create();
canon := CkXmlDSig_Create();

// Use exclusive XML canonicalization.
canonVersion := 'EXCL_C14N';
withComments := False;
// The optional inclusive namespaces prefix list if using exclusive canonicalization.
prefixList := '';

url := 'https://www.chilkatsoft.com/exampleData/canonicalizeFragmentTest.xml';
success := CkHttp_QuickGetSb(http,url,sbXml);

// This is the input XML:

// <?xml version="1.0" encoding="UTF-8"?>
// <Signature xmlns="http://www.w3.org/2000/09/xmldsig#">
// <SignedInfo>
//   <CanonicalizationMethod Algorithm="http://www.w3.org/TR/2001/REC-xml-c14n-20010315" />
//   <SignatureMethod Algorithm="http://www.w3.org/2000/09/xmldsig#rsa-sha1" />
//   <Reference URI="#object">
//     <DigestMethod Algorithm="http://www.w3.org/2000/09/xmldsig#sha1" />
//     <DigestValue>OPnpF/ZNLDxJ/I+1F3iHhlmSwgo=</DigestValue>
//   </Reference>
// </SignedInfo>
// <SignatureValue>nihUFQg4mDhLgecvhIcKb9Gz8VRTOlw+adiZOBBXgK4JodEe5aFfCqm8WcRIT8GL
// LXSk8PsUP4//SsKqUBQkpotcAqQAhtz2v9kCWdoUDnAOtFZkd/CnsZ1sge0ndha4
// 0wWDV+nOWyJxkYgicvB8POYtSmldLLepPGMz+J7/Uws=</SignatureValue>
// <KeyInfo>
//   <KeyValue>
//     <RSAKeyValue>
//       <Modulus>4IlzOY3Y9fXoh3Y5f06wBbtTg94Pt6vcfcd1KQ0FLm0S36aGJtTSb6pYKfyX7PqC
//       UQ8wgL6xUJ5GRPEsu9gyz8ZobwfZsGCsvu40CWoT9fcFBZPfXro1Vtlh/xl/yYHm
//       +Gzqh0Bw76xtLHSfLfpVOrmZdwKmSFKMTvNXOFd0V18=</Modulus>
//       <Exponent>AQAB</Exponent>
//     </RSAKeyValue>
//   </KeyValue>
// </KeyInfo>
// <Object Id="object">some text
//   with spaces and CR-LF.</Object>
// </Signature>

// Canonicalize and return the fragment of XML starting at the element where the Id attribute equals "object".
xmlCanonFrag := CkXmlDSig__canonicalizeFragment(canon,CkStringBuilder__getAsString(sbXml),'object',canonVersion,prefixList,withComments);
Memo1.Lines.Add(xmlCanonFrag);

// The output is:
// 
// <Object xmlns="http://www.w3.org/2000/09/xmldsig#" Id="object">some text
//   with spaces and CR-LF.</Object>
// 

CkHttp_Dispose(http);
CkStringBuilder_Dispose(sbXml);
CkXmlDSig_Dispose(canon);

end;