public static ContinuationPacket ReadFrom(ArraySegment <byte> segment, int maxDataSize)
{
if (segment.Count < NoDataSize)
{
throw new InvalidPacketSizeException(segment,
$"Data is too small, expected {NoDataSize} bytes but provided only {segment.Count}");
}
var result = new ContinuationPacket();
using (var stream = new MemoryStream(segment.Array, segment.Offset, segment.Count))
{
var reader = new EndianReader(stream, Endianness.BigEndian);
result.ChannelIdentifier = reader.ReadUInt32();
result.PaketSequence = reader.ReadByte();
CheckSequence(segment, result.PaketSequence);
}
var remainingBytes = Math.Min(maxDataSize, segment.Count - NoDataSize);
result.Data = new ArraySegment <byte>(segment.Array, segment.Offset + NoDataSize, remainingBytes);
return(result);
}
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);
}
public static ContinuationPacket ReadFrom(ArraySegment<byte> segment, int maxDataSize)
{
if (segment.Count < NoDataSize)
{
throw new InvalidPacketSizeException(segment,
$"Data is too small, expected {NoDataSize} bytes but provided only {segment.Count}");
}
var result = new ContinuationPacket();
using (var stream = new MemoryStream(segment.Array, segment.Offset, segment.Count))
{
var reader = new EndianReader(stream, Endianness.BigEndian);
result.ChannelIdentifier = reader.ReadUInt32();
result.PaketSequence = reader.ReadByte();
CheckSequence(segment, result.PaketSequence);
}
var remainingBytes = Math.Min(maxDataSize, segment.Count - NoDataSize);
result.Data = new ArraySegment<byte>(segment.Array, segment.Offset + NoDataSize, remainingBytes);
return result;
}
static IHidOutputReport ToOutputReport(IHidDevice device, ContinuationPacket continuation)
{
var report = device.CreateOutputReport();
continuation.WriteTo(report.Data);
return report;
}
