C#

RSA Encrypt Randomly Generated AES Key

See more RSA Examples

Demonstrates how to RSA encrypt a randomly generated AES key. C#

bool success = false;

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

// First generate a 256-bit AES key (32 bytes).
Chilkat.Prng prng = new Chilkat.Prng();
Chilkat.BinData bdAesKey = new Chilkat.BinData();
success = prng.GenRandomBd(32,bdAesKey);

// Use a public key from a certificate for RSA encryption.
Chilkat.Cert cert = new Chilkat.Cert();

success = cert.LoadFromFile("qa_data/pem/mf_public_rsa.pem");
if (success == false) {
    Debug.WriteLine(cert.LastErrorText);
    return;
}

Chilkat.PublicKey pubKey = new Chilkat.PublicKey();
cert.GetPublicKey(pubKey);

Chilkat.Rsa rsa = new Chilkat.Rsa();
success = rsa.UsePublicKey(pubKey);
if (success == false) {
    Debug.WriteLine(rsa.LastErrorText);
    return;
}

// RSA encrypt our 32-byte AES key.
// The contents of bdAesKey are replaced with result of the RSA encryption.
success = rsa.EncryptBd(bdAesKey,false);
if (success == false) {
    Debug.WriteLine(rsa.LastErrorText);
    return;
}

// Return the result as a base64 string
string encryptedAesKey = bdAesKey.GetEncoded("base64");

Debug.WriteLine("encrypted AES key = " + encryptedAesKey);