(MFC) Verify XML Digital Signature

Verifies XML signatures in an XML file.

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

See Also: Using MFC CString in Chilkat

#include <CkStringBuilder.h>
#include <CkXmlDSig.h>

void ChilkatSample(void)
    {
    CkString strOut;

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

    CkStringBuilder sbXml;
    bool success = sbXml.LoadFile("qa_data/xml_dsig_verify/csioz_sample.xml","utf-8");
    if (success != true) {
        strOut.append("Failed to load XML file.");
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    CkXmlDSig dsig;

    // First load the XML containing the signatures to be verified.
    success = dsig.LoadSignatureSb(sbXml);
    if (success != true) {
        strOut.append(dsig.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    // It's possible that an XML document can contain multiple signatures.
    // Each can be verified as follows:
    int i = 0;
    while (i < dsig.get_NumSignatures()) {
        // Select the Nth signature by setting the Selector property.
        dsig.put_Selector(i);

        // The bVerifyReferenceDigests argument determines if we want
        // to also verify each reference digest.  If set to false,
        // then only the SignedInfo part of the Signature is verified.
        bool bVerifyReferenceDigests = true;
        bool bVerified = dsig.VerifySignature(bVerifyReferenceDigests);
        strOut.append("Signature ");
        strOut.appendInt(i + 1);
        strOut.append(" verified = ");
        strOut.appendInt(bVerified);
        strOut.append("\r\n");

        i = i + 1;
    }



    SetDlgItemText(IDC_EDIT1,strOut.getUnicode());

    }