public static async Task <IActionResult> GetKeys(HttpRequest req, TraceWriter log, ExecutionContext context, bool returnAppSKey)
{
string devAddr = req.Query["devAddr"];
if (devAddr == null)
{
string errorMsg = "Missing devAddr in querystring";
//log.Error(errorMsg);
throw new Exception(errorMsg);
}
var config = new ConfigurationBuilder()
.SetBasePath(context.FunctionAppDirectory)
.AddJsonFile("local.settings.json", optional: true, reloadOnChange: true)
.AddEnvironmentVariables()
.Build();
string connectionString = config.GetConnectionString("IoTHubConnectionString");
if (connectionString == null)
{
string errorMsg = "Missing IoTHubConnectionString in settings";
//log.Error(errorMsg);
throw new Exception(errorMsg);
}
RegistryManager registryManager = RegistryManager.CreateFromConnectionString(connectionString);
//Currently registry manager query only support select so we need to check for injection on the devaddr only for "'"
//TODO check for sql injection
devAddr = devAddr.Replace('\'', ' ');
var query = registryManager.CreateQuery($"SELECT * FROM devices WHERE tags.DevAddr = '{devAddr}'", 1);
LoraDeviceInfo loraDeviceInfo = new LoraDeviceInfo();
loraDeviceInfo.DevAddr = devAddr;
while (query.HasMoreResults)
{
var page = await query.GetNextAsTwinAsync();
//we query only for 1 result
foreach (var twin in page)
{
loraDeviceInfo.DevEUI = twin.DeviceId;
if (returnAppSKey)
{
loraDeviceInfo.AppSKey = twin.Tags["AppSKey"].Value;
}
loraDeviceInfo.NwkSKey = twin.Tags["NwkSKey"].Value;
if (twin.Tags.Contains("GatewayID"))
{
loraDeviceInfo.GatewayID = twin.Tags["GatewayID"].Value;
}
if (twin.Tags.Contains("SensorDecoder"))
{
loraDeviceInfo.SensorDecoder = twin.Tags["SensorDecoder"].Value;
}
if (twin.Tags.Contains("AppEUI"))
{
loraDeviceInfo.AppEUI = twin.Tags["AppEUI"].Value;
}
loraDeviceInfo.IsOurDevice = true;
if (twin.Properties.Reported.Contains("FCntUp"))
{
loraDeviceInfo.FCntUp = twin.Properties.Reported["FCntUp"];
}
if (twin.Properties.Reported.Contains("FCntDown"))
{
loraDeviceInfo.FCntDown = twin.Properties.Reported["FCntDown"];
}
}
}
if (loraDeviceInfo.IsOurDevice)
{
var device = await registryManager.GetDeviceAsync(loraDeviceInfo.DevEUI);
loraDeviceInfo.PrimaryKey = device.Authentication.SymmetricKey.PrimaryKey;
}
string json = JsonConvert.SerializeObject(loraDeviceInfo);
return((ActionResult) new OkObjectResult(json));
}
public static async Task <IActionResult> PerformOTAA(HttpRequest req, TraceWriter log, ExecutionContext context, bool returnAppSKey)
{
string json;
string AppKey;
string AppSKey;
string NwkSKey;
string DevAddr;
string DevNonce;
string AppNonce;
string devEUI = req.Query["devEUI"];
if (devEUI == null)
{
string errorMsg = "Missing devEUI in querystring";
//log.Error(errorMsg);
throw new Exception(errorMsg);
}
string appEUI = req.Query["appEUI"];
if (appEUI == null)
{
string errorMsg = "Missing appEUI in querystring";
//log.Error(errorMsg);
throw new Exception(errorMsg);
}
DevNonce = req.Query["devNonce"];
if (DevNonce == null)
{
string errorMsg = "Missing devNonce in querystring";
//log.Error(errorMsg);
throw new Exception(errorMsg);
}
string GatewayID = req.Query["GatewayID"];
var config = new ConfigurationBuilder()
.SetBasePath(context.FunctionAppDirectory)
.AddJsonFile("local.settings.json", optional: true, reloadOnChange: true)
.AddEnvironmentVariables()
.Build();
var connectionString = config.GetConnectionString("IoTHubConnectionString");
if (connectionString == null)
{
string errorMsg = "Missing IoTHubConnectionString in settings";
//log.Error(errorMsg);
throw new Exception(errorMsg);
}
RegistryManager registryManager = RegistryManager.CreateFromConnectionString(connectionString);
LoraDeviceInfo loraDeviceInfo = new LoraDeviceInfo();
loraDeviceInfo.DevEUI = devEUI;
var twin = await registryManager.GetTwinAsync(devEUI);
if (twin != null)
{
loraDeviceInfo.IsOurDevice = true;
//Make sure that there is the AppEUI and it matches if not we cannot do the OTAA
if (!twin.Tags.Contains("AppEUI"))
{
string errorMsg = $"Missing AppEUI for OTAA for device {devEUI}";
//log.Error(errorMsg);
throw new Exception(errorMsg);
}
else
{
if (twin.Tags["AppEUI"].Value != appEUI)
{
string errorMsg = $"AppEUI for OTAA does not match for device {devEUI}";
//log.Error(errorMsg);
throw new Exception(errorMsg);
}
}
//Make sure that there is the AppKey if not we cannot do the OTAA
if (!twin.Tags.Contains("AppKey"))
{
string errorMsg = $"Missing AppKey for OTAA for device {devEUI}";
//log.Error(errorMsg);
throw new Exception(errorMsg);
}
else
{
AppKey = twin.Tags["AppKey"].Value;
}
//Make sure that is a new request and not a replay
if (twin.Tags.Contains("DevNonce"))
{
if (twin.Tags["DevNonce"] == DevNonce)
{
string errorMsg = $"DevNonce already used for device {devEUI}";
log.Info(errorMsg);
loraDeviceInfo.DevAddr = DevNonce;
loraDeviceInfo.IsJoinValid = false;
json = JsonConvert.SerializeObject(loraDeviceInfo);
return((ActionResult) new OkObjectResult(json));
}
}
//Check that the device is joining throught the linked gateway and not another
if (twin.Tags.Contains("GatewayID"))
{
if (!String.IsNullOrEmpty(twin.Tags["GatewayID"].Value) && twin.Tags["GatewayID"].Value.ToUpper() != GatewayID.ToUpper())
{
string errorMsg = $"Not the right gateway device-gateway:{twin.Tags["GatewayID"].Value} current-gateway:{GatewayID}";
log.Info(errorMsg);
loraDeviceInfo.DevAddr = DevNonce;
if (twin.Tags.Contains("GatewayID"))
{
loraDeviceInfo.GatewayID = twin.Tags["GatewayID"].Value;
}
loraDeviceInfo.IsJoinValid = false;
json = JsonConvert.SerializeObject(loraDeviceInfo);
return((ActionResult) new OkObjectResult(json));
}
}
byte[] netId = new byte[3] {
0, 0, 1
};
AppNonce = OTAAKeysGenerator.getAppNonce();
AppSKey = OTAAKeysGenerator.calculateKey(new byte[1] {
0x02
}, OTAAKeysGenerator.StringToByteArray(AppNonce), netId, OTAAKeysGenerator.StringToByteArray(DevNonce), OTAAKeysGenerator.StringToByteArray(AppKey));
NwkSKey = OTAAKeysGenerator.calculateKey(new byte[1] {
0x01
}, OTAAKeysGenerator.StringToByteArray(AppNonce), netId, OTAAKeysGenerator.StringToByteArray(DevNonce), OTAAKeysGenerator.StringToByteArray(AppKey));;
//check that the devaddr is unique in the IoTHub registry
bool isDevAddrUnique = false;
do
{
DevAddr = OTAAKeysGenerator.getDevAddr(netId);
var query = registryManager.CreateQuery($"SELECT * FROM devices WHERE tags.DevAddr = '{DevAddr}'", 1);
if (query.HasMoreResults)
{
var page = await query.GetNextAsTwinAsync();
if (!page.GetEnumerator().MoveNext())
{
isDevAddrUnique = true;
}
else
{
isDevAddrUnique = false;
}
}
else
{
isDevAddrUnique = true;
}
} while (!isDevAddrUnique);
var patch = new
{
tags = new
{
AppSKey,
NwkSKey,
DevAddr,
DevNonce
}
};
await registryManager.UpdateTwinAsync(loraDeviceInfo.DevEUI, JsonConvert.SerializeObject(patch), twin.ETag);
loraDeviceInfo.DevAddr = DevAddr;
loraDeviceInfo.AppKey = twin.Tags["AppKey"].Value;
loraDeviceInfo.NwkSKey = NwkSKey;
loraDeviceInfo.AppSKey = AppSKey;
loraDeviceInfo.AppNonce = AppNonce;
loraDeviceInfo.AppEUI = appEUI;
loraDeviceInfo.NetId = BitConverter.ToString(netId).Replace("-", "");;
if (!returnAppSKey)
{
loraDeviceInfo.AppSKey = null;
}
//Accept the JOIN Request and the futher messages
loraDeviceInfo.IsJoinValid = true;
var device = await registryManager.GetDeviceAsync(loraDeviceInfo.DevEUI);
loraDeviceInfo.PrimaryKey = device.Authentication.SymmetricKey.PrimaryKey;
if (twin.Tags.Contains("GatewayID"))
{
loraDeviceInfo.GatewayID = twin.Tags["GatewayID"].Value;
}
if (twin.Tags.Contains("SensorDecoder"))
{
loraDeviceInfo.SensorDecoder = twin.Tags["SensorDecoder"].Value;
}
}
else
{
loraDeviceInfo.IsOurDevice = false;
}
json = JsonConvert.SerializeObject(loraDeviceInfo);
return((ActionResult) new OkObjectResult(json));
}
