(C) Generate a Random 256-bit AES Key and RSA Encrypt

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Generates a random 256-bit AES key and encrypts using an RSA public key. Only the owner of the RSA private key will be able to decrypt the AES key.

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#include <C_CkPublicKey.h>
#include <C_CkRsa.h>
#include <C_CkBinData.h>
#include <C_CkPrng.h>

void ChilkatSample(void)
    {
    HCkPublicKey pubKey;
    BOOL success;
    HCkRsa rsa;
    HCkBinData bdAesKey;
    HCkPrng prng;

    // The RSA public key is used for encryption, and the private key for decryption.

    // The public key's role is to make encryption accessible to anyone while ensuring that
    // only the private key holder can decrypt the messages.
    // The public key is designed to be widely distributed so anyone can use it to encrypt messages
    // intended for the owner of the private key.

    // Load our 2048-bit RSA public key.
    pubKey = CkPublicKey_Create();
    // In all Chilkat methods expecting a path, you pass either absolute or relative paths.
    success = CkPublicKey_LoadFromFile(pubKey,"rsaKeys/Test2048Rsa.pem");
    if (success == FALSE) {
        printf("%s\n",CkPublicKey_lastErrorText(pubKey));
        CkPublicKey_Dispose(pubKey);
        return;
    }

    rsa = CkRsa_Create();

    // Tell RSA to use the public key.
    CkRsa_ImportPublicKeyObj(rsa,pubKey);

    // Generate a random 256-bit AES key (32 bytes)
    bdAesKey = CkBinData_Create();
    prng = CkPrng_Create();
    CkPrng_GenRandomBd(prng,32,bdAesKey);

    // RSA encrypt.
    CkRsa_EncryptBd(rsa,bdAesKey,FALSE);

    // Save the RSA encrypted AES key to a file.
    success = CkBinData_WriteFile(bdAesKey,"rsaEncrypted/myAes.key");


    CkPublicKey_Dispose(pubKey);
    CkRsa_Dispose(rsa);
    CkBinData_Dispose(bdAesKey);
    CkPrng_Dispose(prng);

    }