public static void OpenDigitalEnvelope(string envelopeFile, string RSAprivateKey, string outputFile, EncryptionMode mode, SymetricAlgorithm algorithm)
{
var envelope = FileManager.Read_Envelope(envelopeFile);
var privateKey = FileManager.Read_RSAKey(RSAprivateKey);
var keyCipher = Convert.ToBase64String(HelperFunctions.FromHexToByte(envelope.Key));
var key = RSA.Decrypt(keyCipher, privateKey.Modulus, privateKey.Exponent);
var input = Convert.FromBase64String(envelope.Data);
var keyBytes = HelperFunctions.FromHexToByte(key);
var vector = FileManager.ReadFile_IVector("IVector.txt");
var data = algorithm == SymetricAlgorithm.THREE_DES ? THREE_DES.Decrypt(input, keyBytes, mode) : AES.Decrypt(input, keyBytes, vector, mode);
var envelopeText = Encoding.ASCII.GetString(data);
FileManager.Write(envelopeText, outputFile);
}
public static void CreateDigitalEnvelope(string textFile, string RSApublicKey, string outputFile, EncryptionMode mode, SymetricAlgorithm algorithm, KeySize keySize)
{
var envelope = new HelperClasses.Envelope();
var text = FileManager.ReadFile_Byte(textFile);
var vector = FileManager.ReadFile_IVector("IVector.txt");
byte[] cryptedText;
byte[] key;
if (algorithm == SymetricAlgorithm.THREE_DES)
{
key = HelperFunctions.GenerateKey((int)keySize);
cryptedText = THREE_DES.Encrypt(text, key, mode);
}
else
{
key = HelperFunctions.GenerateKey((int)keySize);
cryptedText = AES.Encrypt(text, key, vector, mode);
}
var keyHex = HelperFunctions.FromByteToHex(key);
var publicKey = FileManager.Read_RSAKey(RSApublicKey);
var RSAcrypted = RSA.Encrypt(keyHex, publicKey.Modulus, publicKey.Exponent);
var cryptedKey = Convert.FromBase64String(RSAcrypted);
RSAcrypted = HelperFunctions.FromByteToHex(cryptedKey);
envelope.Data = Convert.ToBase64String(cryptedText);
envelope.Key = RSAcrypted;
FileManager.Write_Envelope(outputFile, envelope, key.Length * 8, publicKey.Modulus.Length * 4, algorithm);
}
