public DownlinkMessage(byte[] payload,
ulong xtime,
ReceiveWindow?rx1,
ReceiveWindow rx2,
DevEui devEui,
RxDelay lnsRxDelay,
LoRaDeviceClassType deviceClassType,
StationEui stationEui = default,
uint?antennaPreference = null)
{
if (payload is null)
{
throw new ArgumentNullException(nameof(payload));
}
Data = payload;
DevEui = devEui;
LnsRxDelay = lnsRxDelay;
DeviceClassType = deviceClassType;
AntennaPreference = antennaPreference;
Rx1 = rx1;
Rx2 = rx2;
StationEui = stationEui;
Xtime = xtime;
}
private static DownlinkMessage BuildDownstreamMessage(LoRaDevice loRaDevice,
StationEui stationEUI,
ILogger logger,
ulong xTime,
ReceiveWindow?rx1,
ReceiveWindow rx2,
RxDelay lnsRxDelay,
LoRaPayloadData loRaMessage,
LoRaDeviceClassType deviceClassType,
uint?antennaPreference = null)
{
var messageBytes = loRaMessage.Serialize(loRaDevice.AppSKey.Value, loRaDevice.NwkSKey.Value);
var downlinkMessage = new DownlinkMessage(
messageBytes,
xTime,
rx1, rx2,
loRaDevice.DevEUI,
lnsRxDelay,
deviceClassType,
stationEUI,
antennaPreference
);
if (logger.IsEnabled(LogLevel.Debug))
{
logger.LogDebug($"{loRaMessage.MessageType} {JsonConvert.SerializeObject(downlinkMessage)}");
}
return(downlinkMessage);
}
private static uint CalculateRXWindowsTime(uint windowTime, RxDelay rxDelay)
{
// RxDelay follows specification of RXTimingSetupReq and the delay
// | rXDelay | Delay |
// ===================
// | 0 | 1 |
// | 1 | 1 |
// | 2 | 2 |
// | 3 | 3 |
return((uint)(Enum.IsDefined(rxDelay) ? windowTime + rxDelay.ToSeconds() - 1 : windowTime));
}
public override byte[] PerformEncryption(string appSkey)
{
byte[] pt;
if (!CfList.Span.IsEmpty)
{
pt = AppNonce.ToArray().Concat(NetID.ToArray()).Concat(DevAddr.ToArray()).Concat(DlSettings.ToArray()).Concat(RxDelay.ToArray()).Concat(CfList.ToArray()).Concat(Mic.ToArray()).ToArray();
}
else
{
pt = AppNonce.ToArray().Concat(NetID.ToArray()).Concat(DevAddr.ToArray()).Concat(DlSettings.ToArray()).Concat(RxDelay.ToArray()).Concat(Mic.ToArray()).ToArray();
}
Aes aes = new AesManaged();
aes.Key = ConversionHelper.StringToByteArray(appSkey);
aes.IV = new byte[16];
aes.Mode = CipherMode.ECB;
aes.Padding = PaddingMode.None;
ICryptoTransform cipher;
cipher = aes.CreateDecryptor();
var encryptedPayload = cipher.TransformFinalBlock(pt, 0, pt.Length);
RawMessage = new byte[encryptedPayload.Length];
Array.Copy(encryptedPayload, 0, RawMessage, 0, encryptedPayload.Length);
return(encryptedPayload);
}
/// <summary>
/// Write the value to a bytes buffer.
/// </summary>
public static Span <byte> Write(this RxDelay delay, Span <byte> buffer)
{
buffer[0] = (byte)delay;
return(buffer[sizeof(RxDelay)..]);
/// <summary> /// Converts to <see cref="TimeSpan"/>, if valid. /// </summary> public static TimeSpan ToTimeSpan(this RxDelay delay) => TimeSpan.FromSeconds(ToSeconds(delay));
/// <summary> /// Converts to integral seconds, if valid. /// </summary> public static int ToSeconds(this RxDelay delay) => Enum.IsDefined(delay) ? (delay is RxDelay.RxDelay0 ? 1 : (int)delay) : throw new ArgumentException(null, nameof(delay));
/// <summary> /// Increments delay by a second. /// </summary> public static RxDelay Inc(this RxDelay delay) => (RxDelay) checked ((byte)(delay + 1));
