// 미밴드 인증
async public void Authenticate(OnAuthHandler callback = null)
{
GattDeviceServicesResult servicesResult = await manager.Device.GetGattServicesForUuidAsync(new Guid(ATS_UUID));
if (servicesResult.Status == GattCommunicationStatus.Success && servicesResult.Services.Count > 0)
{
GattDeviceService service = servicesResult.Services[0];
GattCharacteristicsResult characteristicsResult = await service.GetCharacteristicsForUuidAsync(new Guid(ATC_UUID));
if (characteristicsResult.Status == GattCommunicationStatus.Success && characteristicsResult.Characteristics.Count > 0)
{
GattCharacteristic characteristic = characteristicsResult.Characteristics[0];
// Enable notification
GattCommunicationStatus status = await characteristic.WriteClientCharacteristicConfigurationDescriptorAsync(GattClientCharacteristicConfigurationDescriptorValue.Notify);
if (status == GattCommunicationStatus.Success)
{
characteristic.ValueChanged += (GattCharacteristic sender, GattValueChangedEventArgs args) => {
var reader = DataReader.FromBuffer(args.CharacteristicValue);
byte[] messageType = new byte[3]; reader.ReadBytes(messageType);
if (messageType[1] == 0x01) // Request random number
{
if (messageType[2] == 0x01)
{
manager.Write(sender, new byte[] { 0x02, 0x08 });
}
else
{
callback.Invoke(this, false);
service.Dispose();
}
}
else if (messageType[1] == 0x02) // Get random number
{
byte[] number = new byte[reader.UnconsumedBufferLength];
reader.ReadBytes(number);
// Encrypt number
byte[] encNumber;
using (Aes aes = Aes.Create()) {
aes.Key = _authKey;
aes.Mode = CipherMode.ECB;
aes.Padding = PaddingMode.None;
ICryptoTransform encryptor = aes.CreateEncryptor(aes.Key, new byte[] { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }); // Constant iv, bad :(
using (MemoryStream stream = new MemoryStream()) {
using (CryptoStream cryptoStream = new CryptoStream(stream, encryptor, CryptoStreamMode.Write)) {
cryptoStream.Write(number, 0, number.Length);
cryptoStream.FlushFinalBlock();
encNumber = stream.ToArray();
}
}
}
// Send encrypted number
using (var stream = new MemoryStream()) {
stream.Write(new byte[] { 0x03, 0x08 }, 0, 2);
stream.Write(encNumber, 0, encNumber.Length);
manager.Write(characteristic, stream.ToArray());
}
}
else if (messageType[1] == 0x03)
{
if (messageType[2] == 0x01)
{
callback.Invoke(this, true);
}
else
{
callback.Invoke(this, false);
service.Dispose();
}
}
};
}
// Define auth secret key
byte[] hash = new SHA256Managed().ComputeHash(Guid.NewGuid().ToByteArray());
_authKey = hash.Take(16).ToArray();
// Send key it to device
using (var stream = new MemoryStream()) {
stream.Write(new byte[] { 0x01, 0x08 }, 0, 2);
stream.Write(_authKey, 0, _authKey.Length);
manager.Write(characteristic, stream.ToArray());
}
}
}
}