(Unicode C) RSA Signature with Certificate's Private Key from PFX

See more RSA Examples

Demonstrates how to use a certificate's private key from a PFX file to create an RSA signature.

Chilkat C/C++ Library Downloads
MS Visual C/C++ Linux/CentOS C/C++ Alpine Linux C/C++ MAC OS X C/C++	armhf/aarch64 C/C++ C++ Builder iOS C/C++ Android C/C++	Solaris C/C++ MinGW C/C++

#include <C_CkCertStoreW.h>
#include <C_CkCertW.h>
#include <C_CkPrivateKeyW.h>
#include <C_CkRsaW.h>

void ChilkatSample(void)
    {
    HCkCertStoreW certStore;
    BOOL success;
    HCkCertW cert;
    HCkPrivateKeyW pkey;
    const wchar_t *pkeyXml;
    HCkRsaW rsa;
    const wchar_t *strData;
    const wchar_t *hexSig;

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

    // Create an instance of a certificate store object, load a PFX file,
    // locate the certificate we need, and use it for signing.
    // (a PFX file may contain more than one certificate.)
    certStore = CkCertStoreW_Create();

    // The 1st argument is the filename, the 2nd arg is the 
    // PFX file's password:
    success = CkCertStoreW_LoadPfxFile(certStore,L"chilkat.pfx",L"test");
    if (success != TRUE) {
        wprintf(L"%s\n",CkCertStoreW_lastErrorText(certStore));
        CkCertStoreW_Dispose(certStore);
        return;
    }

    cert = CkCertStoreW_FindCertBySubject(certStore,L"Chilkat Software, Inc.");
    if (CkCertStoreW_getLastMethodSuccess(certStore) == FALSE) {
        wprintf(L"%s\n",CkCertStoreW_lastErrorText(certStore));
        CkCertStoreW_Dispose(certStore);
        return;
    }

    pkey = CkCertW_ExportPrivateKey(cert);
    if (CkCertW_getLastMethodSuccess(cert) == FALSE) {
        wprintf(L"%s\n",CkCertW_lastErrorText(cert));
        CkCertW_Dispose(cert);
        CkCertStoreW_Dispose(certStore);
        return;
    }

    CkCertW_Dispose(cert);

    // Get the private key in XML format:
    pkeyXml = CkPrivateKeyW_getXml(pkey);

    rsa = CkRsaW_Create();

    // Import the private key into the RSA component:
    success = CkRsaW_ImportPrivateKey(rsa,pkeyXml);
    if (success != TRUE) {
        wprintf(L"%s\n",CkRsaW_lastErrorText(rsa));
        CkPrivateKeyW_Dispose(pkey);
        CkCertStoreW_Dispose(certStore);
        CkRsaW_Dispose(rsa);
        return;
    }

    // Encode the signature as a hex string
    CkRsaW_putEncodingMode(rsa,L"hex");

    strData = L"This is the string to be signed.";

    // Sign the string using the sha-1 hash algorithm.
    // Other valid choices are "sha-256", "md2" and "md5".
    hexSig = CkRsaW_signStringENC(rsa,strData,L"sha-1");

    wprintf(L"%s\n",hexSig);

    CkPrivateKeyW_Dispose(pkey);

    wprintf(L"Success!\n");


    CkCertStoreW_Dispose(certStore);
    CkRsaW_Dispose(rsa);

    }