public EncryptedPacket EncryptDataWithIntegrity(byte[] originalMessage, RsaWithRsaParameterKey rsaParams)
{
// Sender generates AES session key
byte[] sessionKey = _cryptographyExample.GenerateRandomNumber(32);
// Sender generates Initialization Vector
byte[] initializationVector = _cryptographyExample.GenerateRandomNumber(16);
// Sender stores that IV in the packet object
EncryptedPacket EP = new EncryptedPacket
{
IV = initializationVector
};
// Sender encrypts data using AES
EP.EncryptedData = _cryptographyExample.EncryptUsingAES(originalMessage, sessionKey, EP.IV);
//Sender encrypts the session key with RSA
EP.EncryptedSessionKey = rsaParams.EncryptData(sessionKey);
// create an HMAC using the session key and store an HMAC of the encrypted data in the packet
using (HMACSHA256 hmac = new HMACSHA256(sessionKey))
{
EP.Hmac = hmac.ComputeHash(EP.EncryptedData);
}
return(EP);
}
public EncryptedPacket EncryptDataWithSignature(byte[] originalMessage, RsaWithRsaParameterKey rsaParams, DigitalSignatures DS)
{
// Sender generates AES session key
byte[] sessionKey = _cryptographyExample.GenerateRandomNumber(32);
// Sender generates Initialization Vector
byte[] initializationVector = _cryptographyExample.GenerateRandomNumber(16);
// Sender stores that IV in the packet object
EncryptedPacket EP = new EncryptedPacket
{
IV = initializationVector
};
// Sender encrypts data using AES
EP.EncryptedData = _cryptographyExample.EncryptUsingAES(originalMessage, sessionKey, EP.IV);
//Sender encrypts the session key with RSA
EP.EncryptedSessionKey = rsaParams.EncryptData(sessionKey);
// Sender generates hash mac using our session key
using (HMACSHA256 hmac = new HMACSHA256(sessionKey))
{
EP.Hmac = hmac.ComputeHash(EP.EncryptedData);
}
//Sender signs the message with a digital signature
EP.Signature = DS.SignData(EP.Hmac);
return(EP);
}
public EncryptedPacket EncryptData(byte[] originalMessage, RsaWithRsaParameterKey rsaParams)
{
// Sender generates AES session key
byte[] sessionKey = _cryptographyExample.GenerateRandomNumber(32);
// Sender generates Initialization Vector
byte[] initializationVector = _cryptographyExample.GenerateRandomNumber(16);
// Sender stores that IV in the packet object
EncryptedPacket EP = new EncryptedPacket
{
IV = initializationVector
};
// Sender encrypts data using AES
EP.EncryptedData = _cryptographyExample.EncryptUsingAES(originalMessage, sessionKey, EP.IV);
//Sender encrypts the session key with RSA
EP.EncryptedSessionKey = rsaParams.EncryptData(sessionKey);
return(EP);
}