/// <summary>
/// Get the frame from the transmitter.
/// </summary>
/// <returns>The decoded Frame. Null if Frame was corrupted or there was no data in the transmitter.</returns>
private Frame GetReceivedFrame()
{
if (transmitter.DataReceived(StationId))
{
// there is indeed a data, we are going to get it
BitArray encodedFrameBitArray = transmitter.GetData(StationId);
// Decode the frame
Tuple <BitArray, HammingHelper.Status> tuple = HammingHelper.DecryptManager(encodedFrameBitArray, CorrectionMode, EncodedFramePadding);
BitArray frameBitArray = tuple.Item1;
// Keeps the current return type as the last received ones
ReturnTypeOfLastReceivedFrame = tuple.Item2;
// If Hamming detected an error, we return null because the frame is corrupted and Hamming did not fix it
bool isCorrupted = tuple.Item2 == HammingHelper.Status.DETECTED;
if (isCorrupted)
{
Console.WriteLine("corrupted frame received");
return(null);
}
// Converts BitArray to Frame
Frame frame = Frame.GetFrameFromBitArray(frameBitArray);
bool isInvalidFrame = frame.Id >= MaxSequence ||
!Enum.IsDefined(typeof(Constants.FrameType), (int)frame.Type) ||
frame.Ack >= MaxSequence ||
frame.DataSize > DataSizeInFrame ||
frame.Data.Count / 8 > DataSizeInFrame;
if (isInvalidFrame)
{
Console.WriteLine("invalid frame received");
return(null);
}
Console.WriteLine("{4, 11} {0, 12} : id={1, 2}, type={2, 4}, ack={3, 2}, data lenght={5, 3}", "ReceiveFrame", frame.Id, frame.Type.ToString(), frame.Ack, StationId == Constants.StationId.Station1 ? "Station 1" : "Station 2", frame.DataSize);
return(frame);
}
return(null);
}
public void TestEncryptDecryptManager()
{
// #1 case 10000010 (8 bits)
BitArray bitArray = new BitArray(8)
{
[0] = true,
[6] = true
};
BitArray bitArrayEncrypt = HammingHelper.EncryptManager(bitArray, HammingHelper.Mode.CORRECT).Item1;
BitArray bitArrayDecrypt = HammingHelper.DecryptManager(bitArrayEncrypt, HammingHelper.Mode.CORRECT).Item1;
Assert.AreEqual(HammingHelper.BitArrayToDigitString(bitArray), HammingHelper.BitArrayToDigitString(bitArrayDecrypt));
// # Random case
bitArray = new BitArray(32)
{
[0] = false,
[6] = true,
[8] = true,
[18] = true,
[20] = true,
[29] = true,
};
Tuple <BitArray, HammingHelper.Status> tupleEncrypt = HammingHelper.EncryptManager(bitArray, HammingHelper.Mode.CORRECT);
Tuple <BitArray, HammingHelper.Status> tupleDecrypt = HammingHelper.DecryptManager(tupleEncrypt.Item1, HammingHelper.Mode.CORRECT);
Assert.AreEqual(HammingHelper.Status.OK, tupleEncrypt.Item2);
Assert.AreEqual(HammingHelper.Status.OK, tupleDecrypt.Item2);
Assert.AreEqual(HammingHelper.BitArrayToDigitString(bitArray), HammingHelper.BitArrayToDigitString(tupleDecrypt.Item1));
// # Random case with 1 error (CORRECTED)
bitArray = new BitArray(8)
{
[0] = true,
[3] = true,
[5] = true,
};
tupleEncrypt = HammingHelper.EncryptManager(bitArray, HammingHelper.Mode.CORRECT);
tupleEncrypt.Item1[9] = !tupleEncrypt.Item1[9]; // Inject error here
tupleDecrypt = HammingHelper.DecryptManager(tupleEncrypt.Item1, HammingHelper.Mode.CORRECT);
Assert.AreEqual(HammingHelper.Status.OK, tupleEncrypt.Item2);
Assert.AreEqual(HammingHelper.Status.CORRECTED, tupleDecrypt.Item2);
Assert.AreEqual(HammingHelper.BitArrayToDigitString(bitArray), HammingHelper.BitArrayToDigitString(tupleDecrypt.Item1));
// # Random case with 2 error (DETECTED)
bitArray = new BitArray(8)
{
[0] = true,
[3] = true,
[5] = true,
};
tupleEncrypt = HammingHelper.EncryptManager(bitArray, HammingHelper.Mode.DETECT);
tupleEncrypt.Item1[1] = !tupleEncrypt.Item1[1]; // Inject error here
tupleEncrypt.Item1[9] = !tupleEncrypt.Item1[9]; // Inject error here
tupleDecrypt = HammingHelper.DecryptManager(tupleEncrypt.Item1, HammingHelper.Mode.DETECT);
Assert.AreEqual(HammingHelper.Status.OK, tupleEncrypt.Item2);
Assert.AreEqual(HammingHelper.Status.DETECTED, tupleDecrypt.Item2);
// # Random case with 3 error (1 CORRECTED and 2 DETECTED)
bitArray = new BitArray(16)
{
[0] = true,
[1] = true,
[5] = true,
[7] = true,
[13] = true,
};
tupleEncrypt = HammingHelper.EncryptManager(bitArray, HammingHelper.Mode.CORRECT);
tupleEncrypt.Item1[1] = !tupleEncrypt.Item1[1]; // Inject error here (first 13 bits)
tupleEncrypt.Item1[20] = !tupleEncrypt.Item1[20]; // Inject error here (second 13 bits)
tupleEncrypt.Item1[25] = !tupleEncrypt.Item1[25]; // Inject error here (second 13 bits)
tupleDecrypt = HammingHelper.DecryptManager(tupleEncrypt.Item1, HammingHelper.Mode.CORRECT);
Assert.AreEqual(HammingHelper.Status.OK, tupleEncrypt.Item2);
Assert.AreEqual(HammingHelper.Status.DETECTED, tupleDecrypt.Item2);
// # Random case with 3 error (NOT SUPPORTED)
bitArray = new BitArray(8)
{
[0] = true,
[1] = true,
[5] = true,
};
tupleEncrypt = HammingHelper.EncryptManager(bitArray, HammingHelper.Mode.CORRECT);
tupleEncrypt.Item1[1] = !tupleEncrypt.Item1[1]; // Inject error here
tupleEncrypt.Item1[5] = !tupleEncrypt.Item1[5]; // Inject error here
tupleEncrypt.Item1[9] = !tupleEncrypt.Item1[9]; // Inject error here
tupleDecrypt = HammingHelper.DecryptManager(tupleEncrypt.Item1, HammingHelper.Mode.CORRECT);
Assert.AreEqual(HammingHelper.Status.OK, tupleEncrypt.Item2);
Assert.AreEqual(HammingHelper.Status.DETECTED, tupleDecrypt.Item2);
// # Random case with 1 (Detect only 1 bit)
bitArray = new BitArray(8)
{
[0] = true,
[1] = true,
[5] = true,
};
tupleEncrypt = HammingHelper.EncryptManager(bitArray, HammingHelper.Mode.DETECT);
tupleEncrypt.Item1[1] = !tupleEncrypt.Item1[1]; // Inject error here
tupleDecrypt = HammingHelper.DecryptManager(tupleEncrypt.Item1, HammingHelper.Mode.DETECT);
Assert.AreEqual(HammingHelper.Status.OK, tupleEncrypt.Item2);
Assert.AreEqual(HammingHelper.Status.DETECTED, tupleDecrypt.Item2);
// # Brute force cases
for (int num = 0; num < 256; ++num)
{
for (int i = 0; i < 13; ++i)
{
for (int j = 0; j < 13; ++j)
{
if (i == j)
{
continue;
}
byte[] bytes = BitConverter.GetBytes(num);
bitArray = new BitArray(new[] { bytes[0] });
tupleEncrypt = HammingHelper.EncryptManager(bitArray, HammingHelper.Mode.CORRECT);
tupleEncrypt.Item1[j] = !tupleEncrypt.Item1[j]; // Inject error here
tupleEncrypt.Item1[i] = !tupleEncrypt.Item1[i]; // Inject error here
tupleDecrypt = HammingHelper.DecryptManager(tupleEncrypt.Item1, HammingHelper.Mode.CORRECT);
Assert.AreEqual(HammingHelper.Status.OK, tupleEncrypt.Item2);
Assert.AreEqual(HammingHelper.Status.DETECTED, tupleDecrypt.Item2);
}
}
}
}
