(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 <C_CkCertStoreW.h>
#include <C_CkCertW.h>
#include <C_CkRsaW.h>
#include <C_CkByteData.h>
#include <C_CkFileAccessW.h>

void ChilkatSample(void)
    {
    HCkCertStoreW certStore;
    const wchar_t *thumbprint;
    BOOL bReadOnly;
    BOOL success;
    HCkCertW cert;
    HCkRsaW rsa;
    BOOL bUsePrivateKey;
    HCkByteData dataToSign;
    HCkByteData sigData;
    HCkFileAccessW fac;

    //  First get the A3 certificate that was installed on the Windows system.
    certStore = CkCertStoreW_Create();

    thumbprint = L"12c1dd8015f3f03f7b1fa619dc24e2493ca8b4b2";

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

    //  Find the certificate with the desired thumbprint
    //  (There are many ways to locate a certificate.  This example chooses to find by thumbprint.)
    cert = CkCertStoreW_FindCertBySha1Thumbprint(certStore,thumbprint);
    if (CkCertStoreW_getLastMethodSuccess(certStore) != TRUE) {
        wprintf(L"Failed to find the certificate.\n");
        CkCertStoreW_Dispose(certStore);
        return;
    }

    wprintf(L"Found: %s\n",CkCertW_subjectCN(cert));

    rsa = CkRsaW_Create();

    //  Provide the cert's private key
    bUsePrivateKey = TRUE;
    success = CkRsaW_SetX509Cert(rsa,cert,bUsePrivateKey);
    CkCertW_Dispose(cert);
    if (success != TRUE) {
        wprintf(L"%s\n",CkRsaW_lastErrorText(rsa));
        CkCertStoreW_Dispose(certStore);
        CkRsaW_Dispose(rsa);
        return;
    }

    //  Now we're ready to sign..
    dataToSign = CkByteData_Create();
    sigData = CkByteData_Create();

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

    success = CkRsaW_SignBytes(rsa,dataToSign,L"SHA-256",sigData);
    if (success != TRUE) {
        wprintf(L"%s\n",CkRsaW_lastErrorText(rsa));
        CkCertStoreW_Dispose(certStore);
        CkRsaW_Dispose(rsa);
        CkByteData_Dispose(dataToSign);
        CkByteData_Dispose(sigData);
        CkFileAccessW_Dispose(fac);
        return;
    }

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


    CkCertStoreW_Dispose(certStore);
    CkRsaW_Dispose(rsa);
    CkByteData_Dispose(dataToSign);
    CkByteData_Dispose(sigData);
    CkFileAccessW_Dispose(fac);

    }