public static string DecryptData(EncryptedPacket encryptedPacket, RSAWithRSAParameterKey rsaParams)
{
var aes = new AesEncryption();
// Decrypt AES key with RSA and then decrypt data with AES.
var decryptedSessionKey = rsaParams.DecryptData(encryptedPacket.EncryptedSessionKey);
var decryptedData = aes.Decrypt(encryptedPacket.EncryptedData, decryptedSessionKey, encryptedPacket.Iv);
return(Encoding.UTF8.GetString(decryptedData));
}
public byte[] DecryptData(EncryptedPacket encryptedPacket, RSAWithRSAParameterKey rsaParams)
{
var decryptedSessionKey = rsaParams.DecryptData(encryptedPacket.EncryptedSessionKey);
var decryptedData = _aes.Decrypt(encryptedPacket.EncryptedData, decryptedSessionKey,
encryptedPacket.Iv, encryptedPacket.Tag, null);
return(decryptedData);
}
public byte[] DecryptData(EncryptedPacket encryptedPacket, RSAWithRSAParameterKey rsaParams)
{
// Decrypt AES Key with RSA.
var decryptedSessionKey = rsaParams.DecryptData(encryptedPacket.EncryptedSessionKey);
// Decrypt our data with AES using the decrypted session key.
var decryptedData = _aes.Decrypt(encryptedPacket.EncryptedData,
decryptedSessionKey, encryptedPacket.Iv);
return(decryptedData);
}
private static void TestRSAWithRSAParameterKey()
{
var rsaParams = new RSAWithRSAParameterKey();
const string original = "Text to encrypt";
rsaParams.AssignNewKey();
var encryptedRSAParams = rsaParams.EncryptData(Encoding.UTF8.GetBytes(original));
var decryptedRSAParams = rsaParams.DecryptData(encryptedRSAParams);
Console.WriteLine($"Original Text: {original}");
Console.WriteLine($"Encrypted RSA Params: {Convert.ToBase64String(encryptedRSAParams)}");
Console.WriteLine($"Decrypted RSA Params: {Convert.ToBase64String(decryptedRSAParams)}");
Console.WriteLine($"Decrypted Text: {Encoding.Default.GetString(decryptedRSAParams)}");
}
public byte[] DecryptData(EncryptedPacket encryptedPacket, RSAWithRSAParameterKey rsaParams)
{
// Decrypt AES Key with RSA
var decryptedSessionKey = rsaParams.DecryptData(encryptedPacket.EncryptedSessionKey);
// Integrity Check
var hmacToCheck = HMac.ComputeHMACSha256(encryptedPacket.EncryptedData, decryptedSessionKey);
if (!Compare(encryptedPacket.HMAC, hmacToCheck))
{
throw new CryptographicException("HMAC for decryption does not match encrypted package HMAC code received. This means the message has been tampered with.");
}
// Decrypt our data with AES using the decryptedSessionKey
return(_aes.Decrypt(encryptedPacket.EncryptedData, decryptedSessionKey, encryptedPacket.IV));
}
public static string DecryptData(EncryptedPacket encryptedPacket, RSAWithRSAParameterKey rsaParams)
{
var aes = new AesEncryption();
// Decrypt AES key with RSA and then decrypt data with AES.
var decryptedSessionKey = rsaParams.DecryptData(encryptedPacket.EncryptedSessionKey);
using (var hmac = new HMACSHA256(decryptedSessionKey))
{
var hmacToCheck = hmac.ComputeHash(encryptedPacket.EncryptedData);
if (!CompareArrays.Compare(encryptedPacket.Hmac, hmacToCheck))
{
throw new CryptographicException("HMAC for decryption does not match encrypted packet.");
}
}
var decryptedData = aes.Decrypt(encryptedPacket.EncryptedData, decryptedSessionKey, encryptedPacket.Iv);
return(Encoding.UTF8.GetString(decryptedData));
}