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Unicode C++

PKCS7 Sign Text using RSA 2048, SHA256, Base64 Output

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Demonstrates how to sign text using 2048-bit RSA with SHA256, producing PKCS#7 output in Base64. The certificate w/ private key used for signing is loaded from a .p12/.pfx file.

Chilkat Unicode C++ Downloads

Unicode C++
#include <CkCertW.h>
#include <CkCrypt2W.h>

void ChilkatSample(void)
    {
    bool success = false;

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

    CkCertW cert;

    // Load the cert and private key.  Whatever the private key happens to be,
    // such as RSA or ECC, then Chilkat will use it.  If the private key is 
    // a 2048-bit RSA key, then that's what will be used..
    success = cert.LoadPfxFile(L"qa_data/pfx/myCertAndKey.p12",L"password");
    if (success != true) {
        wprintf(L"%s\n",cert.lastErrorText());
        return;
    }

    CkCrypt2W crypt;

    success = crypt.SetSigningCert(cert);
    if (success != true) {
        wprintf(L"%s\n",crypt.lastErrorText());
        return;
    }

    // Use SHA-256
    crypt.put_HashAlgorithm(L"sha256");

    // Hash the utf-8 byte representation of the string
    crypt.put_Charset(L"utf-8");

    // Return the result in base64
    crypt.put_EncodingMode(L"base64");

    // Sign some text..
    const wchar_t *textToSign = L"This is the text to be hashed and signed.";
    const wchar_t *sigBase64 = crypt.opaqueSignStringENC(textToSign);
    if (crypt.get_LastMethodSuccess() != true) {
        wprintf(L"%s\n",crypt.lastErrorText());
        return;
    }

    wprintf(L"%s\n",sigBase64);

    // The result:
    // MIIS2wYJKoZIhvcNAQc ... zGeeY4Oxg==
    }