(Unicode C++) Encrypt File using X.509 Certificate using AES in CBC Mode

Demonstrates how to encrypt a file using an X.509 Certificate's public key, where the underlying bulk encryption algorithm is 128-bit AES in CBC mode. (The underlying bulk encryption algorithm can be specified to be other algorithms/strengths.)

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#include <CkCrypt2W.h>
#include <CkCertW.h>

void ChilkatSample(void)
    {
    //  This example requires the Chilkat Crypt API to have been previously unlocked.
    //  See Unlock Chilkat Crypt for sample code.

    CkCrypt2W crypt;

    //  Use public-key cryptography for encryption.
    crypt.put_CryptAlgorithm(L"pki");

    //  Get an X.509 certificate to use for encrypting.
    //  Note: Chilkat provides many different ways of loading a certificate, from many different formats,
    //  or if on Windows, from the installed certificates on the system.
    //  This example simply loads a certificate from a file.
    //  Also, for encryption, only the public key is needed.  Digital certificates embed the public key
    //  within the X.509 format itself.  Therefore, if you have a certificate, you also have the public key.
    CkCertW cert;
    bool success = cert.LoadFromFile(L"qa_data/certs/testCert.cer");
    if (success != true) {
        wprintf(L"%s\n",cert.lastErrorText());
        return;
    }

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

    //  Indicate the underlying bulk encryption algorithm to be used:
    crypt.put_Pkcs7CryptAlg(L"aes");
    crypt.put_KeyLength(128);

    //  Note: When doing public-key encryption the underlying bulk symmetric cipher mode will always be CBC. (at least with Chilkat...)

    //  There's one last option that could be set.  If is the RSA encryption encryption/padding scheme.
    //  By default, RSAES_PKCS1-V1_5 is used.  If desired, the OaepPadding property could be set to true to
    //  use RSAES_OAEP.  (We'll leave it set at the default value of false)
    crypt.put_OaepPadding(false);

    //  Everything is specified.  Now just encrypt...
    //  The output is PKCS7 in binary DER format.
    success = crypt.CkEncryptFile(L"qa_data/hamlet.xml",L"qa_output/hamlet.p7");
    if (success != true) {
        wprintf(L"%s\n",crypt.lastErrorText());
        return;
    }

    wprintf(L"Finished.\n");
    }