public void DecryptFile(IFileReader fileReader, IFileWriter fileWriter, uint d)
{
if (fileReader == null)
{
throw new ArgumentNullException(nameof(fileReader));
}
if (fileWriter == null)
{
throw new ArgumentNullException(nameof(fileWriter));
}
if (d < 1)
{
throw new ArgumentException($"{nameof(d)} must be higher than 0");
}
KeysFromLastRun.Clear();
RsaKeysFromLastRun.Clear();
var e = fileReader.ReadBits(32);
var n = fileReader.ReadBits(32);
var keys = GetKeysFromFile(fileReader, n, d);
var indexOfByte = 0;
while (!fileReader.ReachedEndOfFile)
{
var encryptedByte = (byte)fileReader.ReadBits(8);
var decryptedByte = DecryptByte(encryptedByte, keys, indexOfByte);
fileWriter.WriteValueOnBits(decryptedByte, 8);
indexOfByte++;
}
}
public void EncryptFile(IFileReader fileReader, IFileWriter fileWriter, uint n, uint e)
{
if (fileReader == null)
{
throw new ArgumentNullException(nameof(fileReader));
}
if (fileWriter == null)
{
throw new ArgumentNullException(nameof(fileWriter));
}
if (n < 1)
{
throw new ArgumentException($"{nameof(n)} must be higher than 0");
}
if (e < 1)
{
throw new ArgumentException($"{nameof(e)} must be higher than 0");
}
KeysFromLastRun.Clear();
RsaKeysFromLastRun.Clear();
// TODO: Is it normal for the random key to be smaller than n?
var randomKeys = GetRandomKeys(n - 1);
var rsaKeys = GetRsaKeys(randomKeys, n, e);
fileWriter.WriteValueOnBits(e, 32);
fileWriter.WriteValueOnBits(n, 32);
WriteRsaKeysToFile(rsaKeys, fileWriter);
var currentIndex = 0;
while (!fileReader.ReachedEndOfFile)
{
var currentByte = (byte)fileReader.ReadBits(8);
var encodedByte = GetEncodedByte(currentByte, randomKeys, currentIndex);
fileWriter.WriteValueOnBits(encodedByte, 8);
currentIndex++;
}
}