(MFC) Alliance Access LAU Sign Message (XML Signature using HMAC-SHA-256)

Demonstrates how to sign XML according to the requirements for Alliance Access LAU (Local Authentication) using HMAC-SHA-256.

Chilkat C/C++ Library Downloads MS Visual C/C++ Libs

See Also: Using MFC CString in Chilkat

#include <CkXml.h>
#include <CkXmlDSigGen.h>
#include <CkStringBuilder.h>

void ChilkatSample(void)
    {
    CkString strOut;

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

    // We begin with this message:

    // <?xml version="1.0" encoding="utf-8"?>
    // <Saa:DataPDU xmlns:Saa="urn:swift:saa:xsd:saa.2.0" xmlns:Sw="urn:swift:snl:ns.Sw"
    //   xmlns:SwGbl="urn:swift:snl:ns.SwGbl" xmlns:SwInt="urn:swift:snl:ns:SwInt" xmlns:SwSec="url:swift:snl:ns.SwSec">
    //     <Saa:Revision>2.0.7</Saa:Revision>
    //     <Saa:Header>
    //         <Saa:Message>
    // 			<test>blah blah</test>
    //         </Saa:Message>
    //     </Saa:Header>
    //     <Saa:Body>...</Saa:Body>
    //     <Saa:LAU>
    //     </Saa:LAU>
    // </Saa:DataPDU>

    // And we want so sign to create this as the result:
    // The signed XML we'll create will not be indented and pretty-printed like this.
    // Instead, we'll use the "CompactSignedXml" behavior to produce compact single-line XML.

    // <?xml version="1.0" encoding="utf-8"?>
    // <Saa:DataPDU xmlns:Saa="urn:swift:saa:xsd:saa.2.0" xmlns:Sw="urn:swift:snl:ns.Sw"
    //   xmlns:SwGbl="urn:swift:snl:ns.SwGbl" xmlns:SwInt="urn:swift:snl:ns:SwInt" xmlns:SwSec="url:swift:snl:ns.SwSec">
    //     <Saa:Revision>2.0.7</Saa:Revision>
    //     <Saa:Header>
    //         <Saa:Message>
    // 			<test>blah blah</test>
    //         </Saa:Message>
    //     </Saa:Header>
    //     <Saa:Body>...</Saa:Body>
    //     <Saa:LAU>
    //         <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#"/>
    //                 <ds:SignatureMethod Algorithm="http://www.w3.org/2001/04/xmldsig-more#hmac-sha256"/>
    //                 <ds:Reference URI="">
    //                     <ds:Transforms>
    //                         <ds:Transform Algorithm="http://www.w3.org/2000/09/xmldsig#enveloped-signature"/>
    //                         <ds:Transform Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#"/>
    //                     </ds:Transforms>
    //                     <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>
    //                     <ds:DigestValue>Y7oScHnYOUQvni/TSzZbDec+HR+mWIFH149GXpwj1Ws=</ds:DigestValue>
    //                 </ds:Reference>
    //             </ds:SignedInfo>
    //             <ds:SignatureValue>6ynF/FcwbPsHrtlj3h2agJigdnvpbO6hOzKSRGzqkw0=</ds:SignatureValue>
    //         </ds:Signature>
    //     </Saa:LAU>
    // </Saa:DataPDU>

    bool success = true;

    // Create the XML to be signed...

    // (The XML does not need to be created this way.  It can be loaded from a file or a string.)
    // Also, use this online tool to generate code from sample XML: 
    // Generate Code to Create XML

    CkXml xmlToSign;
    xmlToSign.put_Tag("Saa:DataPDU");
    xmlToSign.AddAttribute("xmlns:Saa","urn:swift:saa:xsd:saa.2.0");
    xmlToSign.AddAttribute("xmlns:Sw","urn:swift:snl:ns.Sw");
    xmlToSign.AddAttribute("xmlns:SwGbl","urn:swift:snl:ns.SwGbl");
    xmlToSign.AddAttribute("xmlns:SwInt","urn:swift:snl:ns:SwInt");
    xmlToSign.AddAttribute("xmlns:SwSec","url:swift:snl:ns.SwSec");
    xmlToSign.UpdateChildContent("Saa:Revision","2.0.7");
    xmlToSign.UpdateChildContent("Saa:Header|Saa:Message|test","blah blah");
    xmlToSign.UpdateChildContent("Saa:Body","...");
    xmlToSign.UpdateChildContent("Saa:LAU","");

    CkXmlDSigGen gen;

    gen.put_SigLocation("Saa:DataPDU|Saa:LAU");
    gen.put_SigLocationMod(0);
    gen.put_SigNamespacePrefix("ds");
    gen.put_SigNamespaceUri("http://www.w3.org/2000/09/xmldsig#");
    gen.put_SignedInfoCanonAlg("EXCL_C14N");
    gen.put_SignedInfoDigestMethod("sha256");

    // You may alternatively choose "IndentedSignature" instead of "CompactSignedXml"
    gen.put_Behaviors("CompactSignedXml");

    gen.AddSameDocRef("","sha256","EXCL_C14N","","");

    // Specify the HMAC key.
    // For example, if the HMAC key is to be the us-ascii bytes of the string "secret",
    // the HMAC key can be set in any of the following ways (and also more ways not shown here..)
    gen.SetHmacKey("secret","ascii");
    // or
    gen.SetHmacKey("c2VjcmV0","base64");
    // or
    gen.SetHmacKey("736563726574","hex");

    // Sign the XML..
    CkStringBuilder sbXml;
    xmlToSign.GetXmlSb(sbXml);
    success = gen.CreateXmlDSigSb(sbXml);
    if (success != true) {
        strOut.append(gen.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

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

    // Show the signed XML.
    strOut.append(sbXml.getAsString());
    strOut.append("\r\n");


    SetDlgItemText(IDC_EDIT1,strOut.getUnicode());

    }