(Unicode C++) RSA Sign using Private Key of Certificate Type A3 (smart card / token)

Demonstrates RSA signing data using the private key of a certificate type A3 (smart card, token).

Note: This is a Windows-only example.

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#include <CkCertStoreW.h>
#include <CkCertW.h>
#include <CkRsaW.h>
#include <CkByteData.h>
#include <CkFileAccessW.h>

void ChilkatSample(void)
    {
    //  First get the A3 certificate that was installed on the Windows system.
    CkCertStoreW certStore;

    const wchar_t *thumbprint = L"12c1dd8015f3f03f7b1fa619dc24e2493ca8b4b2";

    //  This is specific to Windows because it is opening the Windows Current-User certificate store.
    bool bReadOnly = true;
    bool success = certStore.OpenCurrentUserStore(bReadOnly);
    if (success != true) {
        wprintf(L"%s\n",certStore.lastErrorText());
        return;
    }

    //  Find the certificate with the desired thumbprint
    //  (There are many ways to locate a certificate.  This example chooses to find by thumbprint.)
    CkCertW *cert = certStore.FindCertBySha1Thumbprint(thumbprint);
    if (certStore.get_LastMethodSuccess() != true) {
        wprintf(L"Failed to find the certificate.\n");
        return;
    }

    wprintf(L"Found: %s\n",cert->subjectCN());

    CkRsaW rsa;

    //  Provide the cert's private key
    bool bUsePrivateKey = true;
    success = rsa.SetX509Cert(*cert,bUsePrivateKey);
    delete cert;
    if (success != true) {
        wprintf(L"%s\n",rsa.lastErrorText());
        return;
    }

    //  Now we're ready to sign..
    CkByteData dataToSign;
    CkByteData sigData;

    //  Get bytes to be signed..
    CkFileAccessW fac;
    success = fac.ReadEntireFile(L"in.dat",dataToSign);

    success = rsa.SignBytes(dataToSign,L"SHA-256",sigData);
    if (success != true) {
        wprintf(L"%s\n",rsa.lastErrorText());
        return;
    }

    wprintf(L"Signature created.\n");
    }