Unicode C

Add EncapsulatedTimestamp to Already-Signed XML

See more XML Digital Signatures Examples

Demonstrates how to add an EncapsulatedTimestamp to an existing XML signature.

Note: This example requires Chilkat v9.5.0.90 or greater.

Unicode C

#include <C_CkStringBuilderW.h>
#include <C_CkXmlDSigW.h>
#include <C_CkJsonObjectW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkStringBuilderW sbXml;
    HCkXmlDSigW dsig;
    HCkJsonObjectW json;
    HCkStringBuilderW sbOut;
    HCkXmlDSigW verifier;
    int numSigs;
    int verifyIdx;
    BOOL verified;

    success = FALSE;

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

    // Note: We cannot load the already-signed XML into a Chilkat XML object because it would re-format the XML when re-emitted.
    // (i.e. indentation and whitespace could change, and it would invalidate the existing signature.)
    // We must use a StringBuilder.
    sbXml = CkStringBuilderW_Create();
    success = CkStringBuilderW_LoadFile(sbXml,L"qa_data/xml_dsig_valid_samples/encapsulatedTimestamp_not_yet_added.xml",L"utf-8");
    if (success == FALSE) {
        wprintf(L"Failed to load the XML file.\n");
        CkStringBuilderW_Dispose(sbXml);
        return;
    }

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

    if (CkXmlDSigW_HasEncapsulatedTimeStamp(dsig) == TRUE) {
        wprintf(L"This signed XML already has an EncapsulatedTimeStamp\n");
        CkStringBuilderW_Dispose(sbXml);
        CkXmlDSigW_Dispose(dsig);
        return;
    }

    // Specify the timestamping authority URL
    json = CkJsonObjectW_Create();
    CkJsonObjectW_UpdateString(json,L"timestampToken.tsaUrl",L"http://timestamp.digicert.com");
    CkJsonObjectW_UpdateBool(json,L"timestampToken.requestTsaCert",TRUE);

    // Call AddEncapsulatedTimeStamp to add the EncapsulatedTimeStamp to the signature.
    // Note: If the signed XML contains multiple signatures, the signature modified is the one 
    // indicated by the dsig.Selector property.
    sbOut = CkStringBuilderW_Create();
    success = CkXmlDSigW_AddEncapsulatedTimeStamp(dsig,json,sbOut);
    if (success == FALSE) {
        wprintf(L"%s\n",CkXmlDSigW_lastErrorText(dsig));
        CkStringBuilderW_Dispose(sbXml);
        CkXmlDSigW_Dispose(dsig);
        CkJsonObjectW_Dispose(json);
        CkStringBuilderW_Dispose(sbOut);
        return;
    }

    CkStringBuilderW_WriteFile(sbOut,L"qa_output/addedEncapsulatedTimeStamp.xml",L"utf-8",FALSE);

    // The EncapsulatedTimeStamp can be validated when validating the signature by adding the VerifyEncapsulatedTimeStamp
    // keyword to UncommonOptions.  See here:

    // ----------------------------------------
    // Verify the signatures we just produced...
    verifier = CkXmlDSigW_Create();
    success = CkXmlDSigW_LoadSignatureSb(verifier,sbOut);
    if (success != TRUE) {
        wprintf(L"%s\n",CkXmlDSigW_lastErrorText(verifier));
        CkStringBuilderW_Dispose(sbXml);
        CkXmlDSigW_Dispose(dsig);
        CkJsonObjectW_Dispose(json);
        CkStringBuilderW_Dispose(sbOut);
        CkXmlDSigW_Dispose(verifier);
        return;
    }

    // Add "VerifyEncapsulatedTimeStamp" to the UncommonOptions to also verify any EncapsulatedTimeStamps
    CkXmlDSigW_putUncommonOptions(verifier,L"VerifyEncapsulatedTimeStamp");

    numSigs = CkXmlDSigW_getNumSignatures(verifier);
    verifyIdx = 0;
    while (verifyIdx < numSigs) {
        CkXmlDSigW_putSelector(verifier,verifyIdx);
        verified = CkXmlDSigW_VerifySignature(verifier,TRUE);
        if (verified != TRUE) {
            wprintf(L"%s\n",CkXmlDSigW_lastErrorText(verifier));
            CkStringBuilderW_Dispose(sbXml);
            CkXmlDSigW_Dispose(dsig);
            CkJsonObjectW_Dispose(json);
            CkStringBuilderW_Dispose(sbOut);
            CkXmlDSigW_Dispose(verifier);
            return;
        }

        verifyIdx = verifyIdx + 1;
    }

    wprintf(L"All signatures were successfully verified.\n");


    CkStringBuilderW_Dispose(sbXml);
    CkXmlDSigW_Dispose(dsig);
    CkJsonObjectW_Dispose(json);
    CkStringBuilderW_Dispose(sbOut);
    CkXmlDSigW_Dispose(verifier);

    }