public void TestConfirmedDataUp()
{
byte[] mhdr = new byte[1];
mhdr[0] = 128;
byte[] devAddr = new byte[4]
{
4, 3, 2, 1
};
byte[] fctrl = new byte[1] {
0
};
byte[] fcnt = new byte[2]
{
0, 0
};
byte[] fport = new byte[1]
{
10
};
byte[] frmPayload = new byte[4]
{
4, 3, 2, 1
};
var appkey = new byte[16] {
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16
};
var nwkkey = new byte[16] {
16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1
};
Array.Reverse(appkey);
Array.Reverse(nwkkey);
LoRaPayloadStandardData lora = new LoRaPayloadStandardData(mhdr, devAddr, fctrl, fcnt, null, fport, frmPayload, 0);
lora.PerformEncryption(BitConverter.ToString(appkey).Replace("-", ""));
byte[] testEncrypt = new byte[4]
{
226, 100, 212, 247
};
Assert.Equal(testEncrypt, lora.frmpayload);
lora.SetMic(BitConverter.ToString(nwkkey).Replace("-", ""));
byte[] testMic = new byte[4]
{
181, 106, 14, 117
};
Assert.Equal(testMic, lora.mic.ToArray());
var mess = Convert.ToBase64String(lora.ToMessage());
Assert.Equal("gAQDAgEAAAAK4mTU97VqDnU=", mess);
}
public void TestUnconfirmedUplink()
{
string jsonUplinkUnconfirmedDataUp = @"{ ""rxpk"":[
{
""time"":""2013-03-31T16:21:17.528002Z"",
""tmst"":3512348611,
""chan"":2,
""rfch"":0,
""freq"":866.349812,
""stat"":1,
""modu"":""LORA"",
""datr"":""SF7BW125"",
""codr"":""4/6"",
""rssi"":-35,
""lsnr"":5.1,
""size"":32,
""data"":""QAQDAgGAAQABppRkJhXWw7WC""
}]}";
byte[] physicalUpstreamPyld = new byte[12];
physicalUpstreamPyld[0] = 2;
var jsonUplinkUnconfirmedDataUpBytes = Encoding.Default.GetBytes(jsonUplinkUnconfirmedDataUp);
LoRaMessage jsonUplinkUnconfirmedMessage = new LoRaMessage(physicalUpstreamPyld.Concat(jsonUplinkUnconfirmedDataUpBytes).ToArray());
Assert.Equal(LoRaMessageType.UnconfirmedDataUp, jsonUplinkUnconfirmedMessage.loRaMessageType);
LoRaPayloadStandardData loRaPayloadUplinkObj = (LoRaPayloadStandardData)jsonUplinkUnconfirmedMessage.payloadMessage;
Assert.True(loRaPayloadUplinkObj.fcnt.SequenceEqual(new byte[2] {
1, 0
}));
Assert.True(loRaPayloadUplinkObj.devAddr.SequenceEqual(new byte[4] {
1, 2, 3, 4
}));
byte[] LoRaPayloadUplinkNwkKey = new byte[16] {
2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2
};
Assert.True(loRaPayloadUplinkObj.CheckMic(BitConverter.ToString(LoRaPayloadUplinkNwkKey).Replace("-", "")));
byte[] LoRaPayloadUplinkAppKey = new byte[16] {
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
};
var key = BitConverter.ToString(LoRaPayloadUplinkAppKey).Replace("-", "");
Assert.Equal("hello", (loRaPayloadUplinkObj.PerformEncryption(key)));
}
private async Task <byte[]> ProcessLoraMessage(LoRaMessage loraMessage)
{
bool validFrameCounter = false;
byte[] udpMsgForPktForwarder = new byte[0];
string devAddr = BitConverter.ToString(loraMessage.payloadMessage.devAddr).Replace("-", "");
Message c2dMsg = null;
Cache.TryGetValue(devAddr, out LoraDeviceInfo loraDeviceInfo);
if (loraDeviceInfo == null)
{
loraDeviceInfo = await LoraDeviceInfoManager.GetLoraDeviceInfoAsync(devAddr);
Logger.Log(loraDeviceInfo.DevEUI, $"processing message, device not in cache", Logger.LoggingLevel.Info);
Cache.AddToCache(devAddr, loraDeviceInfo);
}
else
{
Logger.Log(loraDeviceInfo.DevEUI, $"processing message, device in cache", Logger.LoggingLevel.Info);
}
if (loraDeviceInfo.IsOurDevice)
{
//either there is no gateway linked to the device or the gateway is the one that the code is running
if (String.IsNullOrEmpty(loraDeviceInfo.GatewayID) || loraDeviceInfo.GatewayID.ToUpper() == GatewayID.ToUpper())
{
if (loraMessage.CheckMic(loraDeviceInfo.NwkSKey))
{
if (loraDeviceInfo.HubSender == null)
{
loraDeviceInfo.HubSender = new IoTHubSender(loraDeviceInfo.DevEUI, loraDeviceInfo.PrimaryKey);
}
UInt16 fcntup = BitConverter.ToUInt16(((LoRaPayloadStandardData)loraMessage.payloadMessage).fcnt, 0);
//check if the frame counter is valid: either is above the server one or is an ABP device resetting the counter (relaxed seqno checking)
if (fcntup > loraDeviceInfo.FCntUp || (fcntup == 1 && String.IsNullOrEmpty(loraDeviceInfo.AppEUI)))
{
//save the reset fcnt for ABP (relaxed seqno checking)
if (fcntup == 1 && String.IsNullOrEmpty(loraDeviceInfo.AppEUI))
{
_ = loraDeviceInfo.HubSender.UpdateFcntAsync(fcntup, 0, true);
}
validFrameCounter = true;
Logger.Log(loraDeviceInfo.DevEUI, $"valid frame counter, msg: {fcntup} server: {loraDeviceInfo.FCntUp}", Logger.LoggingLevel.Info);
byte[] decryptedMessage = null;
try
{
decryptedMessage = loraMessage.DecryptPayload(loraDeviceInfo.AppSKey);
}
catch (Exception ex)
{
Logger.Log(loraDeviceInfo.DevEUI, $"failed to decrypt message: {ex.Message}", Logger.LoggingLevel.Error);
}
Rxpk rxPk = ((UplinkPktFwdMessage)loraMessage.loraMetadata.fullPayload).rxpk[0];
dynamic fullPayload = JObject.FromObject(rxPk);
string jsonDataPayload = "";
uint fportUp = (uint)((LoRaPayloadStandardData)loraMessage.payloadMessage).fport[0];
fullPayload.port = fportUp;
fullPayload.fcnt = fcntup;
if (String.IsNullOrEmpty(loraDeviceInfo.SensorDecoder))
{
jsonDataPayload = Convert.ToBase64String(decryptedMessage);
fullPayload.data = jsonDataPayload;
}
else
{
Logger.Log(loraDeviceInfo.DevEUI, $"decoding with: {loraDeviceInfo.SensorDecoder} port: {fportUp}", Logger.LoggingLevel.Info);
jsonDataPayload = LoraDecoders.DecodeMessage(decryptedMessage, fportUp, loraDeviceInfo.SensorDecoder);
fullPayload.data = JObject.Parse(jsonDataPayload);
}
fullPayload.eui = loraDeviceInfo.DevEUI;
fullPayload.gatewayid = GatewayID;
//todo check what the other ts are if milliseconds or seconds
fullPayload.edgets = (long)((startTimeProcessing - new DateTime(1970, 1, 1)).TotalMilliseconds);
string iotHubMsg = fullPayload.ToString(Newtonsoft.Json.Formatting.None);
await loraDeviceInfo.HubSender.SendMessageAsync(iotHubMsg);
Logger.Log(loraDeviceInfo.DevEUI, $"sent message '{jsonDataPayload}' to hub", Logger.LoggingLevel.Info);
loraDeviceInfo.FCntUp = fcntup;
}
else
{
validFrameCounter = false;
Logger.Log(loraDeviceInfo.DevEUI, $"invalid frame counter, msg: {fcntup} server: {loraDeviceInfo.FCntUp}", Logger.LoggingLevel.Info);
}
//start checking for new c2d message, we do it even if the fcnt is invalid so we support replying to the ConfirmedDataUp
//todo ronnie should we wait up to 900 msec?
c2dMsg = await loraDeviceInfo.HubSender.ReceiveAsync(TimeSpan.FromMilliseconds(20));
byte[] bytesC2dMsg = null;
byte[] fport = null;
byte[] fctl = new byte[1] {
32
};
//check if we got a c2d message to be added in the ack message and preprare the message
if (c2dMsg != null)
{
//check if there is another message
var secondC2dMsg = await loraDeviceInfo.HubSender.ReceiveAsync(TimeSpan.FromMilliseconds(20));
if (secondC2dMsg != null)
{
//put it back to the queue for the next pickup
_ = loraDeviceInfo.HubSender.AbandonAsync(secondC2dMsg);
//set the fpending flag so the lora device will call us back for the next message
fctl = new byte[1] {
48
};
}
bytesC2dMsg = c2dMsg.GetBytes();
fport = new byte[1] {
1
};
if (bytesC2dMsg != null)
{
Logger.Log(loraDeviceInfo.DevEUI, $"C2D message: {Encoding.UTF8.GetString(bytesC2dMsg)}", Logger.LoggingLevel.Info);
}
//todo ronnie implement a better max payload size by datarate
//cut to the max payload of lora for any EU datarate
if (bytesC2dMsg.Length > 51)
{
Array.Resize(ref bytesC2dMsg, 51);
}
Array.Reverse(bytesC2dMsg);
}
//if confirmation or cloud to device msg send down the message
if (loraMessage.loRaMessageType == LoRaMessageType.ConfirmedDataUp || c2dMsg != null)
{
//check if we are not too late for the 1 and 2 window
if (((DateTime.UtcNow - startTimeProcessing) <= TimeSpan.FromMilliseconds(1900)))
{
//increase the fcnt down and save it to iot hub twins
loraDeviceInfo.FCntDown++;
Logger.Log(loraDeviceInfo.DevEUI, $"down frame counter: {loraDeviceInfo.FCntDown}", Logger.LoggingLevel.Info);
//Saving both fcnts to twins
_ = loraDeviceInfo.HubSender.UpdateFcntAsync(loraDeviceInfo.FCntUp, loraDeviceInfo.FCntDown);
var _datr = ((UplinkPktFwdMessage)loraMessage.loraMetadata.fullPayload).rxpk[0].datr;
uint _rfch = ((UplinkPktFwdMessage)loraMessage.loraMetadata.fullPayload).rxpk[0].rfch;
double _freq = ((UplinkPktFwdMessage)loraMessage.loraMetadata.fullPayload).rxpk[0].freq;
uint txDelay = 0;
//if we are already longer than 900 mssecond move to the 2 second window
//uncomment to force second windows usage
//Thread.Sleep(901);
if ((DateTime.UtcNow - startTimeProcessing) > TimeSpan.FromMilliseconds(900))
{
if (!string.IsNullOrEmpty(Environment.GetEnvironmentVariable("RX2_DATR")))
{
Logger.Log(loraDeviceInfo.DevEUI, $"using standard second receive windows", Logger.LoggingLevel.Info);
//using EU fix DR for RX2
_freq = 869.525;
_datr = "SF12BW125";
}
//if specific twins are set, specify second channel to be as specified
else
{
_freq = double.Parse(Environment.GetEnvironmentVariable("RX2_FREQ"));
_datr = Environment.GetEnvironmentVariable("RX2_DATR");
Logger.Log(loraDeviceInfo.DevEUI, $"using custom DR second receive windows freq : {_freq}, datr:{_datr}", Logger.LoggingLevel.Info);
}
txDelay = 1000000;
}
long _tmst = ((UplinkPktFwdMessage)loraMessage.loraMetadata.fullPayload).rxpk[0].tmst + txDelay;
Byte[] devAddrCorrect = new byte[4];
Array.Copy(loraMessage.payloadMessage.devAddr, devAddrCorrect, 4);
Array.Reverse(devAddrCorrect);
//todo mik check what is the A0
LoRaPayloadStandardData ackLoRaMessage = new LoRaPayloadStandardData(StringToByteArray("A0"),
devAddrCorrect,
fctl,
BitConverter.GetBytes(loraDeviceInfo.FCntDown),
null,
fport,
bytesC2dMsg,
1);
ackLoRaMessage.PerformEncryption(loraDeviceInfo.AppSKey);
ackLoRaMessage.SetMic(loraDeviceInfo.NwkSKey);
byte[] rndToken = new byte[2];
Random rnd = new Random();
rnd.NextBytes(rndToken);
//todo ronnie should check the device twin preference if using confirmed or unconfirmed down
LoRaMessage ackMessage = new LoRaMessage(ackLoRaMessage, LoRaMessageType.ConfirmedDataDown, rndToken, _datr, 0, _freq, _tmst);
udpMsgForPktForwarder = ackMessage.physicalPayload.GetMessage();
//confirm the message to iot hub only if we are in time for a delivery
if (c2dMsg != null)
{
_ = loraDeviceInfo.HubSender.CompleteAsync(c2dMsg);
Logger.Log(loraDeviceInfo.DevEUI, $"complete the c2d msg to IoT Hub", Logger.LoggingLevel.Info);
}
}
else
{
PhysicalPayload pushAck = new PhysicalPayload(loraMessage.physicalPayload.token, PhysicalIdentifier.PUSH_ACK, null);
udpMsgForPktForwarder = pushAck.GetMessage();
_ = loraDeviceInfo.HubSender.UpdateFcntAsync(loraDeviceInfo.FCntUp, null);
//put back the c2d message to the queue for the next round
_ = loraDeviceInfo.HubSender.AbandonAsync(c2dMsg);
Logger.Log(loraDeviceInfo.DevEUI, $"too late for down message, sending only ACK to gateway", Logger.LoggingLevel.Info);
}
}
//No ack requested and no c2d message we send the udp ack only to the gateway
else if (loraMessage.loRaMessageType == LoRaMessageType.UnconfirmedDataUp && c2dMsg == null)
{
PhysicalPayload pushAck = new PhysicalPayload(loraMessage.physicalPayload.token, PhysicalIdentifier.PUSH_ACK, null);
udpMsgForPktForwarder = pushAck.GetMessage();
if (validFrameCounter)
{
_ = loraDeviceInfo.HubSender.UpdateFcntAsync(loraDeviceInfo.FCntUp, null);
}
}
}
else
{
Logger.Log(loraDeviceInfo.DevEUI, $"with devAddr {devAddr} check MIC failed. Device will be ignored from now on", Logger.LoggingLevel.Info);
loraDeviceInfo.IsOurDevice = false;
}
}
else
{
Logger.Log(loraDeviceInfo.DevEUI, $"ignore message because is not linked to this GatewayID", Logger.LoggingLevel.Info);
}
}
else
{
Logger.Log(devAddr, $"device with devAddr {devAddr} is not our device, ignore message", Logger.LoggingLevel.Info);
}
Logger.Log(loraDeviceInfo.DevEUI, $"processing time: {DateTime.UtcNow - startTimeProcessing}", Logger.LoggingLevel.Info);
return(udpMsgForPktForwarder);
}