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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.

Chilkat C++ Downloads

C++
#include <CkPublicKey.h>
#include <CkRsa.h>
#include <CkBinData.h>
#include <CkPrng.h>

void ChilkatSample(void)
    {
    bool success = false;

    //  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.
    CkPublicKey pubKey;
    //  In all Chilkat methods expecting a path, you pass either absolute or relative paths.
    success = pubKey.LoadFromFile("rsaKeys/Test2048Rsa.pem");
    if (success == false) {
        std::cout << pubKey.lastErrorText() << "\r\n";
        return;
    }

    CkRsa rsa;

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

    //  Generate a random 256-bit AES key (32 bytes)
    CkBinData bdAesKey;
    CkPrng prng;
    prng.GenRandomBd(32,bdAesKey);

    //  RSA encrypt.
    rsa.EncryptBd(bdAesKey,false);

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