(Delphi DLL) Verify SOAP XML using a wsse:SecurityTokenReference

This example verifies a SOAP XML Digital Signature where the KeyInfo in the XML Signature is a wsse:SecurityTokenReference to the X.509 certificate embedded elsewhere in the SOAP XML.

Chilkat for Delphi Downloads Chilkat non-ActiveX DLL for Delphi Chilkat ActiveX DLL for Delphi * The examples here use the non-ActiveX 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
signedSoapXmlUrl: PWideChar;
http: HCkHttp;
sbXml: HCkStringBuilder;
success: Boolean;
verifier: HCkXmlDSig;
bVerified: Boolean;

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

// The SOAP XML with digital signature verified in this example is available at 
// https://www.chilkatsoft.com/exampleData/signedSoapBinarySecurityToken.xml

signedSoapXmlUrl := 'https://www.chilkatsoft.com/exampleData/signedSoapBinarySecurityToken.xml';

// First, let's get the signed SOAP XML..
http := CkHttp_Create();
sbXml := CkStringBuilder_Create();
success := CkHttp_QuickGetSb(http,signedSoapXmlUrl,sbXml);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkHttp__lastErrorText(http));
    Exit;
  end;

// The signed XML downloaded from the above URL contains the following.
// Note: Everything we need to verify the signature is already available within the signed XML.
// The KeyInfo part of the Signature contains a reference to the wsse:BinarySecurityToken
// For clarity, here is the KeyInfo section extracted from the Signature below:
// 
// <ds:KeyInfo><wsse:SecurityTokenReference><wsse:Reference URI="#x509cert00" ValueType="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-x509-token-profile-1.0#X509" /></wsse:SecurityTokenReference></ds:KeyInfo>
// 
// Chilkat has the capability to automatically follow the SecurityTokenReference.  It will automatically locate the 
// certificate contained in the wsse:BinarySecurityToken element (in this case identified by Id="x509cert00"), 
// automatically extracts the public key from the base64 X.509 certificate, and uses it to verify the signature.

// <?xml version="1.0" encoding="UTF8"?>
// <SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/">
// <SOAP-ENV:Header>
//  <wsse:Security xmlns:ds="http://www.w3.org/2000/09/xmldsig#"
//                 xmlns:wsse="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd"
//                 xmlns:wsu="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd"
//                 xmlns:xenc="http://www.w3.org/2001/04/xmlenc#" SOAP-ENV:mustUnderstand="1">
//  <wsse:BinarySecurityToken
//                EncodingType="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-soap-message-security-1.0#Base64Binary"
//                ValueType="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-x509-token-profile-1.0#X509"
//                wsu:Id="x509cert00">MIIDg...</wsse:BinarySecurityToken>
//  <ds:Signature xmlns:ds="http://www.w3.org/2000/09/xmldsig#"><ds:SignedInfo><ds:CanonicalizationMethod Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#"><InclusiveNamespaces xmlns="http://www.w3.org/2001/10/xml-exc-c14n#" PrefixList="wsse SOAP-ENV"/></ds:CanonicalizationMethod><ds:SignatureMethod Algorithm="http://www.w3.org/2001/04/xmldsig-more#rsa-sha256"/><ds:Reference URI="#TheBody"><ds:Transforms><ds:Transform Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#"/></ds:Transforms><ds:DigestMethod Algorithm="http://www.w3.org/2000/09/xmldsig#sha1"/><ds:DigestValue>VhsSnaEAFsY0OYegKQh99v9csXg=</ds:DigestValue></ds:Reference></ds:SignedInfo><ds:SignatureValue>Ynp3H4rtzpXIh4TaVxkpEkS1bMCCu672aeCzUOzheNNfnpmLsCZz3+zQjMBbchPggCayC5ihpEdhRe3XvPXjPXXAgxDP4mic091QPmjHlmUcu8yqRKfxnPtD35nqaxDtCYw+jGIzj+ch094vA4RPCfY8JQnb1mpy1ZjjsMW8741CIh1epbsd/0bZt6tfINUQ37seg07yvLbCJZ/Zf+h8FlFryQk6lHTTeZl/GfQ9NlDBcShby3x8Hc1KwW++zFqEA7G783R9AYPYn3fWTOBhYk5gkgFc+HaPRLR/L0Bp7ZPbmOR/iZQ+HK4W672tTdN/R2GdN7/deV7QTp2DYK1Z8w==</ds:SignatureValue><ds:KeyInfo><wsse:SecurityTokenReference><wsse:Reference URI="#x509cert00" ValueType="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-x509-token-profile-1.0#X509" /></wsse:SecurityTokenReference></ds:KeyInfo></ds:Signature></wsse:Security>
// </SOAP-ENV:Header>
// <SOAP-ENV:Body xmlns:wsu="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd" wsu:Id="TheBody">
//  <getVersion xmlns="http://msgsec.wssecfvt.ws.ibm.com"/>
// </SOAP-ENV:Body>
// </SOAP-ENV:Envelope>
// 

// To verify this signature, we simply load and verify:
verifier := CkXmlDSig_Create();
success := CkXmlDSig_LoadSignatureSb(verifier,sbXml);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkXmlDSig__lastErrorText(verifier));
    Exit;
  end;

bVerified := CkXmlDSig_VerifySignature(verifier,True);
if (bVerified <> True) then
  begin
    Memo1.Lines.Add(CkXmlDSig__lastErrorText(verifier));
    Exit;
  end;

Memo1.Lines.Add('Signature verified!');

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

end;