(Unicode C) Examine KeyInfo Certificate in XML Signature

This example loads signed XML and gets the signing certificate, assuming the certificate is contained in X509Certificate within the KeyInfo.

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#include <C_CkXmlDSigW.h>
#include <C_CkStringBuilderW.h>
#include <C_CkXmlW.h>
#include <C_CkCertW.h>

void ChilkatSample(void)
    {
    HCkXmlDSigW dsig;
    HCkStringBuilderW sbXml;
    BOOL success;
    HCkXmlW xmlKeyInfo;
    const wchar_t *certBase64;
    HCkCertW cert;

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

    dsig = CkXmlDSigW_Create();
    sbXml = CkStringBuilderW_Create();

    success = CkStringBuilderW_LoadFile(sbXml,L"c:/aaworkarea/elias/3/face_f09006808443a699d1b.xml",L"utf-8");
    if (success != TRUE) {
        wprintf(L"Failed to load XML file.\n");
        CkXmlDSigW_Dispose(dsig);
        CkStringBuilderW_Dispose(sbXml);
        return;
    }

    success = CkXmlDSigW_LoadSignatureSb(dsig,sbXml);
    if (success != TRUE) {
        wprintf(L"%s\n",CkXmlDSigW_lastErrorText(dsig));
        CkXmlDSigW_Dispose(dsig);
        CkStringBuilderW_Dispose(sbXml);
        return;
    }

    // Get the KeyInfo XML.
    xmlKeyInfo = CkXmlDSigW_GetKeyInfo(dsig);
    if (CkXmlDSigW_getLastMethodSuccess(dsig) != TRUE) {
        wprintf(L"%s\n",CkXmlDSigW_lastErrorText(dsig));
        CkXmlDSigW_Dispose(dsig);
        CkStringBuilderW_Dispose(sbXml);
        return;
    }

    wprintf(L"%s\n",CkXmlW_getXml(xmlKeyInfo));
    wprintf(L"----\n");

    // Assuming the X509Certificate is in the KeyInfo, it will look like this:

    //   <ds:KeyInfo Id="...">
    //     <ds:KeyValue>
    //     ...  
    //     <ds:X509Data>
    //       <ds:X509Certificate>MIIHAz...</ds:X509Certificate>
    //     </ds:X509Data>
    //   </ds:KeyInfo>
    certBase64 = CkXmlW_getChildContent(xmlKeyInfo,L"*:X509Data|*:X509Certificate");
    if (CkXmlW_getLastMethodSuccess(xmlKeyInfo) != TRUE) {
        wprintf(L"No X509Certificate found in the KeyInfo.\n");
        CkXmlDSigW_Dispose(dsig);
        CkStringBuilderW_Dispose(sbXml);
        return;
    }

    // Load a certificate object w/ the base64.
    cert = CkCertW_Create();
    success = CkCertW_LoadFromBase64(cert,certBase64);
    if (success != TRUE) {
        wprintf(L"%s\n",CkCertW_lastErrorText(cert));
        CkXmlDSigW_Dispose(dsig);
        CkStringBuilderW_Dispose(sbXml);
        CkCertW_Dispose(cert);
        return;
    }

    // Examine the cert..
    wprintf(L"SubjectDN: %s\n",CkCertW_subjectDN(cert));
    wprintf(L"IssuerDN: %s\n",CkCertW_issuerDN(cert));
    wprintf(L"SerialNumber as Decimal: %s\n",CkCertW_serialDecimal(cert));

    CkXmlW_Dispose(xmlKeyInfo);


    CkXmlDSigW_Dispose(dsig);
    CkStringBuilderW_Dispose(sbXml);
    CkCertW_Dispose(cert);

    }