public static async Task <FidoU2FHidMessage> ReadFidoU2FHidMessageAsync([NotNull] this IHidDevice device, CancellationToken cancellationToken)
{
if (device == null)
{
throw new ArgumentNullException(nameof(device));
}
var initReport = await device.GetInputReportAsync(cancellationToken);
var init = InitializationPacket.ReadFrom(initReport.Data);
var dataSizeReceived = init.Data.Count;
var continuations = new List <ContinuationPacket>();
byte index = 0;
while (dataSizeReceived < init.PayloadLength)
{
var continuationReport = await device.GetInputReportAsync(cancellationToken);
var continuation = ContinuationPacket.ReadFrom(continuationReport.Data, init.PayloadLength - dataSizeReceived);
if (continuation.PaketSequence != index)
{
throw new InvalidSequenceNumberException(continuationReport.Data,
$"The sequence number isn't the expected one, expected {index} but read {continuation.PaketSequence}");
}
continuations.Add(continuation);
dataSizeReceived += continuation.Data.Count;
index += 1;
}
return(BuildMessage(init, continuations));
}
static unsafe void Test(Win32HidDevice device)
{
var init = new InitializationPacket();
init.CommandIdentifier = (byte)U2FHidCommand.Init;
init.ChannelIdentifier = U2FHID_BROADCAST_CID;
init.PayloadLength = 8;
var caps = device.Information.Capabilities;
var buffer = new byte[caps.InputReportByteLength];
fixed(byte *pBuffer = buffer)
{
Marshal.StructureToPtr(init, new IntPtr(pBuffer + 1), false);
buffer[0] = 0x00;
buffer[8] = 0xCA;
buffer[9] = 0xFE;
buffer[10] = 0xBA;
buffer[11] = 0xBE;
buffer[12] = 0xDE;
buffer[13] = 0xAD;
buffer[14] = 0xBA;
buffer[15] = 0xBE;
WriteBuffer(buffer);
var task = Kernel32Dll.WriteFileAsync(device.Handle, new IntPtr(pBuffer), buffer.Length);
var writen = task.Result;
Console.WriteLine("Writen {0} bytes", writen);
}
var bufferOut = new byte[caps.OutputReportByteLength];
fixed(byte *pBuffer = bufferOut)
{
var intPtr = new IntPtr(pBuffer);
var task = Kernel32Dll.ReadFileAsync(device.Handle, intPtr, bufferOut.Length);
var read = task.Result;
Console.WriteLine("Read {0} bytes", read);
}
WriteBuffer(bufferOut);
Wink(device, bufferOut[16], bufferOut[17], bufferOut[18], bufferOut[19]);
}
static Tuple <InitializationPacket, List <ContinuationPacket> > MakeOutputPackets(
int paketLength, FidoU2FHidMessage message)
{
var availableInInit = paketLength - InitializationPacket.NoDataSize;
var availableInContinuation = paketLength - ContinuationPacket.NoDataSize;
var data = message.Data;
var init = new InitializationPacket
{
ChannelIdentifier = message.Channel,
CommandIdentifier = (byte)message.Command,
PayloadLength = (ushort)data.Count,
Data = new ArraySegment <byte>(data.Array, data.Offset,
Math.Min(data.Count, availableInInit))
};
var sizeHandled = init.Data.Count;
var continuations = new List <ContinuationPacket>();
byte sequence = 0;
while (sizeHandled < data.Count)
{
var continuation = new ContinuationPacket
{
ChannelIdentifier = message.Channel,
PaketSequence = sequence,
Data = new ArraySegment <byte>(data.Array, data.Offset + sizeHandled,
Math.Min(data.Count - sizeHandled, availableInContinuation))
};
continuations.Add(continuation);
sizeHandled += continuation.Data.Count;
sequence += 1;
}
return(Tuple.Create(init, continuations));
}
static FidoU2FHidMessage BuildMessage(InitializationPacket init, List <ContinuationPacket> continuations)
{
ArraySegment <byte> data;
if (continuations.Count > 0)
{
// We must allocate memory to reconstruct the message
var stream = new MemoryStream(init.PayloadLength);
stream.Write(init.Data.Array, init.Data.Offset, init.Data.Count);
foreach (var continuation in continuations)
{
stream.Write(continuation.Data.Array, continuation.Data.Offset, continuation.Data.Count);
}
data = stream.ToArray().Segment();
}
else
{
// No need to reconstruct the message
data = init.Data;
}
return(new FidoU2FHidMessage(init.ChannelIdentifier, (U2FHidCommand)init.CommandIdentifier, data));
}
