private async Task DiscoverDevice()
{
var authStageInfo = await SecondaryAuthenticationFactorAuthentication.GetAuthenticationStageInfoAsync();
if (authStageInfo.Stage != SecondaryAuthenticationFactorAuthenticationStage.CollectingCredential)
{
return; // Bad status!
}
findAuth = true;
var deviceList = await SecondaryAuthenticationFactorRegistration.FindAllRegisteredDeviceInfoAsync(SecondaryAuthenticationFactorDeviceFindScope.User);
var db = new DatabaseContext();
var devicesInDb = db.Devices.ToList();
db.Dispose();
IPDiscover.DiscoverIP();
foreach (var device in deviceList)
{
var deviceInDb = devicesInDb.Find(d => d.DeviceId.ToString() == device.DeviceId);
if (deviceInDb == null)
{
continue;
}
var session = new DeviceAuthSession
{
LastIP = deviceInDb.LastConnectedHost,
MACAddress = deviceInDb.DeviceMacAddress,
DeviceID = device.DeviceId,
DeviceInDb = deviceInDb
};
deviceSessions.Add(session);
}
while (findAuth)
{
foreach (var session in deviceSessions)
{
switch (session.Status)
{
case DeviceStatus.NotConnected:
var payload = Convert.ToBase64String(Encoding.UTF8.GetBytes(session.DeviceID));
var data = Encoding.UTF8.GetBytes(DeviceDiscoverPrefix + payload);
if (!string.IsNullOrWhiteSpace(session.LastIP))
{
try
{
UDPListener.Send(session.LastIP, data);
}
catch (Exception)
{
// ignored
}
}
var ips = session.FindIPs()?.ToList();
if ((ips == null || !ips.Any()) && string.IsNullOrWhiteSpace(session.MACAddress) && IPDiscover.IsDiscoveryCompleted)
{
session.Status = DeviceStatus.Unreachable;
continue;
}
if (ips != null)
{
foreach (var ip in ips)
{
try
{
UDPListener.Send(ip, data);
}
catch (Exception)
{
// ignored
}
}
}
await UDPListener.Send(UDPListener.DeviceMulticastGroupAddress, data);
break;
case DeviceStatus.Unreachable:
deviceSessions.Remove(session);
break;
case DeviceStatus.Established:
findAuth = false;
break;
}
}
Thread.Sleep(1000);
}
Auth(deviceSessions.FirstOrDefault(s => s.Status == DeviceStatus.Established));
CurrentSession = null;
}
private async Task AuthenticateWithSmartCardAsync(SmartCard card)
{
var localSettings = Windows.Storage.ApplicationData.Current.LocalSettings;
String m_selectedDeviceId = localSettings.Values["SelectedDevice"] as String;
string m_selectedDeviceFriendlyName = string.Empty;
string m_selectedDeviceAddDate = string.Empty;
string deviceConfigString = string.Empty;
char[] deviceConfigCharArray;
byte[] deviceIdArray = new byte[16];
byte[] deviceDlockState = new byte[1];
bool foundCompanionDevice = false;
byte[] response = { 0 };
string sw1sw2 = null;
SecondaryAuthenticationFactorAuthenticationStageInfo authStageInfo = await SecondaryAuthenticationFactorAuthentication.GetAuthenticationStageInfoAsync();
if ((authStageInfo.Stage != SecondaryAuthenticationFactorAuthenticationStage.CollectingCredential) && (authStageInfo.Stage != SecondaryAuthenticationFactorAuthenticationStage.WaitingForUserConfirmation))
{
throw new Exception("Unexpected! Stage: " + authStageInfo.Stage);
}
//ShowToastNotification("Post Collecting Credential");
System.Diagnostics.Debug.WriteLine("[AuthenticateWithSmartCardAsync] Post Collecting Credential");
IReadOnlyList <SecondaryAuthenticationFactorInfo> deviceList = await SecondaryAuthenticationFactorRegistration.FindAllRegisteredDeviceInfoAsync(
SecondaryAuthenticationFactorDeviceFindScope.AllUsers);
if (deviceList.Count == 0)
{
//ShowToastNotification("Unexpected exception, device list = 0");
throw new Exception("Unexpected exception, device list = 0");
}
SmartCardConnection connection = await card.ConnectAsync();
System.Diagnostics.Debug.WriteLine("[AuthenticateWithSmartCardAsync] Connection");
response = await Apdu.TransmitApduAsync(connection, Apdu.getDeviceGuidCmdApdu);
sw1sw2 = Apdu.ApduResponseParser(response, out response);
deviceIdArray = response;
string deviceId = BitConverter.ToString(response).Replace("-", "");
response = await Apdu.TransmitApduAsync(connection, Apdu.getDlockStateCmdApdu);
sw1sw2 = Apdu.ApduResponseParser(response, out response);
deviceDlockState = response;
//string deviceFriendlyName = null;
byte[] deviceConfigDataArray = new byte[18]; //16 bytes for GUID and 1 byte for dLockstate
IBuffer deviceConfigData;
byte[] deviceConfigurationDataArray;
//List<byte[]> deviceConfigList = new List<byte[]>();
foreach (SecondaryAuthenticationFactorInfo device in deviceList)
{
CryptographicBuffer.CopyToByteArray(device.DeviceConfigurationData, out deviceConfigurationDataArray);
//deviceConfigList.Add(deviceConfigurationDataArray);
//deviceFriendlyName = device.DeviceFriendlyName;
if (device.DeviceId == deviceId)
{
m_selectedDeviceId = deviceId;
m_selectedDeviceFriendlyName = device.DeviceFriendlyName;
deviceConfigString = CryptographicBuffer.ConvertBinaryToString(0, device.DeviceConfigurationData);
//deviceConfigCharArray = new char[deviceConfigString.Count()];
//deviceConfigCharArray = deviceConfigString.ToCharArray();
int count = device.DeviceFriendlyName.Count();
m_selectedDeviceAddDate = deviceConfigString.Substring(35 + 1 + count + 1 + 1);
foundCompanionDevice = true;
//continue;
}
}
//Debugger.Break();
if (!foundCompanionDevice)
{
throw new CompanionDeviceNotFoundException();
}
System.Diagnostics.Debug.WriteLine("[AuthenticateWithSmartCardAsync] Start Nonce APDU sending");
response = await Apdu.TransmitApduAsync(connection, Apdu.getNonceCmdApdu);
sw1sw2 = Apdu.ApduResponseParser(response, out response);
if (sw1sw2 != "9000")
{
throw new UnableTogetNonceFromDeviceException();
}
System.Diagnostics.Debug.WriteLine("[AuthenticateWithSmartCardAsync] Nonce APDU recieved without error");
string nonce = BitConverter.ToString(response).Replace("-", "");
IBuffer svcNonce = CryptographicBuffer.DecodeFromHexString(nonce);
System.Diagnostics.Debug.WriteLine("[AuthenticateWithSmartCardAsync] Start Authentication");
SecondaryAuthenticationFactorAuthenticationResult authResult = await SecondaryAuthenticationFactorAuthentication.StartAuthenticationAsync(
m_selectedDeviceId, svcNonce);
if (authResult.Status != SecondaryAuthenticationFactorAuthenticationStatus.Started)
{
//ShowToastNotification("Unexpected! Could not start authentication!");
throw new Exception("Unexpected! Could not start authentication! Status: " + authResult.Status);
}
byte[] devNonce = { 0 };
byte[] svcHmac = { 0 };
byte[] sessNonce = { 0 };
CryptographicBuffer.CopyToByteArray(authResult.Authentication.ServiceAuthenticationHmac, out svcHmac);
CryptographicBuffer.CopyToByteArray(authResult.Authentication.SessionNonce, out sessNonce);
CryptographicBuffer.CopyToByteArray(authResult.Authentication.DeviceNonce, out devNonce);
byte[] cmd = new byte[Apdu.challengeCmdApdu.Length + svcHmac.Length + sessNonce.Length + devNonce.Length];
System.Buffer.BlockCopy(Apdu.challengeCmdApdu, 0, cmd, 0, Apdu.challengeCmdApdu.Length);
System.Buffer.BlockCopy(svcHmac, 0, cmd, Apdu.challengeCmdApdu.Length, svcHmac.Length);
System.Buffer.BlockCopy(sessNonce, 0, cmd, Apdu.challengeCmdApdu.Length + svcHmac.Length, sessNonce.Length);
System.Buffer.BlockCopy(devNonce, 0, cmd, Apdu.challengeCmdApdu.Length + svcHmac.Length + sessNonce.Length, devNonce.Length);
System.Diagnostics.Debug.WriteLine("[AuthenticateWithSmartCardAsync] Send Challenge");
string str = "\"" + m_selectedDeviceFriendlyName + "\"";
await SecondaryAuthenticationFactorAuthentication.ShowNotificationMessageAsync(
str,
SecondaryAuthenticationFactorAuthenticationMessage.DeviceNeedsAttention);
response = await Apdu.TransmitApduAsync(connection, cmd);
sw1sw2 = Apdu.ApduResponseParser(response, out response);
if (sw1sw2 == "6985")
{
throw new UnauthorizedUserException();
}
else if (sw1sw2 == "6984")
{
//ShowToastNotification("Log-in denied by user");
throw new LogInDeniedByUserException();
}
System.Diagnostics.Debug.WriteLine("[AuthenticateWithSmartCardAsync] Response recieved");
byte[] HMACdk = new byte[32];
byte[] HMACsk = new byte[32];
System.Buffer.BlockCopy(response, 0, HMACdk, 0, 32);
System.Buffer.BlockCopy(response, 32, HMACsk, 0, 32);
IBuffer deviceHmac = CryptographicBuffer.CreateFromByteArray(HMACdk);
IBuffer sessionHmac = CryptographicBuffer.CreateFromByteArray(HMACsk);
SecondaryAuthenticationFactorFinishAuthenticationStatus authStatus = await authResult.Authentication.FinishAuthenticationAsync(deviceHmac,
sessionHmac);
if (authStatus != SecondaryAuthenticationFactorFinishAuthenticationStatus.Completed)
{
//ShowToastNotification("Unable to complete authentication!");
System.Diagnostics.Debug.WriteLine("[AuthenticateWithSmartCardAsync] Unable to complete authentication");
throw new Exception("Unable to complete authentication!");
}
deviceConfigString = "";
if (deviceDlockState[0] == 0)
{
deviceConfigString = deviceId + "-0-1-" + m_selectedDeviceFriendlyName + "-" + m_selectedDeviceAddDate;
}
else
{
deviceConfigString = deviceId + "-1-1-" + m_selectedDeviceFriendlyName + "-" + m_selectedDeviceAddDate;
}
deviceConfigCharArray = new char[deviceConfigString.Count()];
deviceConfigString.CopyTo(0, deviceConfigCharArray, 0, deviceConfigString.Count()); // because deviceConfigString is readonly
deviceConfigCharArray[35] = '1'; // to indicate that device was not used for last login
string deviceConfigStringNew = new string(deviceConfigCharArray);
//Debugger.Break();
deviceConfigData = CryptographicBuffer.ConvertStringToBinary(deviceConfigStringNew, 0);
await SecondaryAuthenticationFactorRegistration.UpdateDeviceConfigurationDataAsync(deviceId, deviceConfigData); //update deviceConfigData
foreach (SecondaryAuthenticationFactorInfo device in deviceList)
{
if (device.DeviceId != deviceId)
{
deviceConfigString = CryptographicBuffer.ConvertBinaryToString(0, device.DeviceConfigurationData);
deviceConfigCharArray = new char[deviceConfigString.Count()];
deviceConfigString.CopyTo(0, deviceConfigCharArray, 0, deviceConfigString.Count()); // decause deviceConfigString is readonly
deviceConfigCharArray[35] = '0'; // to indicate that device was not used for last login
deviceConfigStringNew = new string(deviceConfigCharArray);
deviceConfigData = CryptographicBuffer.ConvertStringToBinary(deviceConfigStringNew, 0);
//Debugger.Break();
await SecondaryAuthenticationFactorRegistration.UpdateDeviceConfigurationDataAsync(device.DeviceId, deviceConfigData); //update deviceConfigData
}
}
System.Diagnostics.Debug.WriteLine("[AuthenticateWithSmartCardAsync] Auth completed");
connection.Dispose();
}
public async void Run(IBackgroundTaskInstance taskInstance)
{
deferral = taskInstance.GetDeferral();
StorageFolder folder = ApplicationData.Current.LocalFolder;
//StorageFile logsFile = await folder.CreateFileAsync("BGtask.txt", CreationCollisionOption.OpenIfExists);
//string txt = "[RUN]: " + DateTime.Now.ToString() + Environment.NewLine;
//await FileIO.WriteTextAsync(logsFile, txt);
// This event is signaled when the operation completes
opCompletedEvent = new ManualResetEvent(false);
SecondaryAuthenticationFactorAuthentication.AuthenticationStageChanged += OnStageChanged;
//ShowToastNotification("BG Task Hit!");
if (taskInstance.TriggerDetails is DeviceWatcherTriggerDetails)
{
DeviceWatcherTriggerDetails triggerDetails = (DeviceWatcherTriggerDetails)taskInstance.TriggerDetails;
foreach (DeviceWatcherEvent e in triggerDetails.DeviceWatcherEvents)
{
switch (e.Kind)
{
case DeviceWatcherEventKind.Add:
Debug.WriteLine("[RUN] Add: " + e.DeviceInformation.Id);
deferral = taskInstance.GetDeferral();
try
{
SecondaryAuthenticationFactorAuthenticationStageInfo authStageInfo = await SecondaryAuthenticationFactorAuthentication.GetAuthenticationStageInfoAsync();
SecondaryAuthenticationFactorAuthenticationStage stage = authStageInfo.Stage;
//Debugger.Break();
if ((authStageInfo.Stage == SecondaryAuthenticationFactorAuthenticationStage.WaitingForUserConfirmation) ||
(authStageInfo.Stage == SecondaryAuthenticationFactorAuthenticationStage.CollectingCredential))
{
System.Diagnostics.Debug.WriteLine("[RUN] Perform Auth / plug trigger");
Task t = PerformAuthentication();
await t;
}
//Debugger.Break();
if (e.DeviceInformation.Name.Contains("Ledger"))
{
Task t = writeConnectedRegisteredDevices();
await t;
}
}
catch (Exception ex)
{
}
finally
{
deferral.Complete();
}
break;
//case DeviceWatcherEventKind.Update:
// Debug.WriteLine("[RUN] Update: " + e.DeviceInformationUpdate.Id);
// deferral = taskInstance.GetDeferral();
//
// try
// {
// Task i = writeConnectedRegisteredDevices();
// await i;
// }
// catch (Exception ex)
// {
// Debugger.Break();
// }
// finally
// {
// deferral.Complete();
// }
// break;
case DeviceWatcherEventKind.Remove:
Debug.WriteLine("[RUN] Remove: " + e.DeviceInformationUpdate.Id);
deferral = taskInstance.GetDeferral();
try
{
List <dLock> pluggedRegisteredDeviceListBeforeRemove = await readConnectedRegisteredDevices();
List <Tuple <string, bool, bool> > pluggedRegisteredDeviceListBeforeRemove_tuple = new List <Tuple <string, bool, bool> >();
foreach (dLock device in pluggedRegisteredDeviceListBeforeRemove)
{
Tuple <string, bool, bool> newElem = new Tuple <string, bool, bool>(device.DeviceId, device.isDlockEnabled, device.isUsedForLastLogin);
pluggedRegisteredDeviceListBeforeRemove_tuple.Add(newElem);
}
IReadOnlyList <SecondaryAuthenticationFactorInfo> registeredDeviceList_removeEvent = await SecondaryAuthenticationFactorRegistration.FindAllRegisteredDeviceInfoAsync(
SecondaryAuthenticationFactorDeviceFindScope.User);
List <SecondaryAuthenticationFactorInfo> pluggedRegisteredDeviceListAfterRemove = await getConnectedRegisteredDeviceList(registeredDeviceList_removeEvent);
foreach (SecondaryAuthenticationFactorInfo deviceToCheck in pluggedRegisteredDeviceListAfterRemove)
{
foreach (dLock device in pluggedRegisteredDeviceListBeforeRemove)
{
if (deviceToCheck.DeviceId == device.DeviceId)
{
var t = pluggedRegisteredDeviceListBeforeRemove_tuple.FirstOrDefault(i => i.Item1 == device.DeviceId);
if (t != null)
{
// delete
pluggedRegisteredDeviceListBeforeRemove_tuple.Remove(t);
}
}
}
}
bool lockDevice = true;
string deviceId = "";
for (int i = 0; i < pluggedRegisteredDeviceListBeforeRemove_tuple.Count(); i++)
{
deviceId = pluggedRegisteredDeviceListBeforeRemove_tuple[i].Item1;
if ((!pluggedRegisteredDeviceListBeforeRemove_tuple[i].Item2) || (!pluggedRegisteredDeviceListBeforeRemove_tuple[i].Item3))
{
lockDevice = false;
}
}
if (lockDevice)
{
Task t = LockDevice(deviceId);
await t;
}
await writeConnectedRegisteredDevices();
}
catch (Exception ex)
{
}
finally
{
deferral.Complete();
}
break;
}
}
}
else
{
Debug.WriteLine("[RUN] Unknown trigger");
deferral = taskInstance.GetDeferral();
//try
//{
// Task t = writeConnectedRegisteredDevices();
// await t;
//}
//catch (ConnectedRegisteredDevicesListTxtFileEmpty Ex)
//{
//}
//finally
//{
// deferral.Complete();
//}
}
// Wait until the operation completes
opCompletedEvent.WaitOne();
deferral.Complete();
}
async void PerformAuthentication()
{
ShowToastNotification("Performing Auth!");
//Get the selected device from app settings
var localSettings = Windows.Storage.ApplicationData.Current.LocalSettings;
String m_selectedDeviceId = localSettings.Values["SelectedDevice"] as String;
SecondaryAuthenticationFactorAuthenticationStageInfo authStageInfo = await SecondaryAuthenticationFactorAuthentication.GetAuthenticationStageInfoAsync();
if (authStageInfo.Stage != SecondaryAuthenticationFactorAuthenticationStage.CollectingCredential)
{
ShowToastNotification("Unexpected!");
throw new Exception("Unexpected!");
}
ShowToastNotification("Post Collecting Credential");
IReadOnlyList <SecondaryAuthenticationFactorInfo> deviceList = await SecondaryAuthenticationFactorRegistration.FindAllRegisteredDeviceInfoAsync(
SecondaryAuthenticationFactorDeviceFindScope.AllUsers);
if (deviceList.Count == 0)
{
ShowToastNotification("Unexpected exception, device list = 0");
throw new Exception("Unexpected exception, device list = 0");
}
ShowToastNotification("Found companion devices");
SecondaryAuthenticationFactorInfo deviceInfo = deviceList.ElementAt(0);
m_selectedDeviceId = deviceInfo.DeviceId;
ShowToastNotification("Device ID: " + m_selectedDeviceId);
//a nonce is an arbitrary number that may only be used once - a random or pseudo-random number issued in an authentication protocol to ensure that old communications cannot be reused in replay attacks.
IBuffer svcNonce = CryptographicBuffer.GenerateRandom(32); //Generate a nonce and do a HMAC operation with the nonce
//In real world, you would need to take this nonce and send to companion device to perform an HMAC operation with it
//You will have only 20 second to get the HMAC from the companion device
SecondaryAuthenticationFactorAuthenticationResult authResult = await SecondaryAuthenticationFactorAuthentication.StartAuthenticationAsync(
m_selectedDeviceId, svcNonce);
if (authResult.Status != SecondaryAuthenticationFactorAuthenticationStatus.Started)
{
ShowToastNotification("Unexpected! Could not start authentication!");
throw new Exception("Unexpected! Could not start authentication!");
}
ShowToastNotification("Auth Started");
//
// WARNING: Test code
// The HAMC calculation SHOULD be done on companion device
//
byte[] combinedDataArray;
CryptographicBuffer.CopyToByteArray(authResult.Authentication.DeviceConfigurationData, out combinedDataArray);
byte[] deviceKeyArray = new byte[32];
byte[] authKeyArray = new byte[32];
for (int index = 0; index < deviceKeyArray.Length; index++)
{
deviceKeyArray[index] = combinedDataArray[index];
}
for (int index = 0; index < authKeyArray.Length; index++)
{
authKeyArray[index] = combinedDataArray[deviceKeyArray.Length + index];
}
// Create device key and authentication key
IBuffer deviceKey = CryptographicBuffer.CreateFromByteArray(deviceKeyArray);
IBuffer authKey = CryptographicBuffer.CreateFromByteArray(authKeyArray);
// Calculate the HMAC
MacAlgorithmProvider hMACSha256Provider = MacAlgorithmProvider.OpenAlgorithm(MacAlgorithmNames.HmacSha256);
CryptographicKey deviceHmacKey = hMACSha256Provider.CreateKey(deviceKey);
IBuffer deviceHmac = CryptographicEngine.Sign(deviceHmacKey, authResult.Authentication.DeviceNonce);
// sessionHmac = HMAC(authKey, deviceHmac || sessionNonce)
IBuffer sessionHmac;
byte[] deviceHmacArray = { 0 };
CryptographicBuffer.CopyToByteArray(deviceHmac, out deviceHmacArray);
byte[] sessionNonceArray = { 0 };
CryptographicBuffer.CopyToByteArray(authResult.Authentication.SessionNonce, out sessionNonceArray);
combinedDataArray = new byte[deviceHmacArray.Length + sessionNonceArray.Length];
for (int index = 0; index < deviceHmacArray.Length; index++)
{
combinedDataArray[index] = deviceHmacArray[index];
}
for (int index = 0; index < sessionNonceArray.Length; index++)
{
combinedDataArray[deviceHmacArray.Length + index] = sessionNonceArray[index];
}
// Get a Ibuffer from combinedDataArray
IBuffer sessionMessage = CryptographicBuffer.CreateFromByteArray(combinedDataArray);
// Calculate sessionHmac
CryptographicKey authHmacKey = hMACSha256Provider.CreateKey(authKey);
sessionHmac = CryptographicEngine.Sign(authHmacKey, sessionMessage);
ShowToastNotification("Before finish auth");
SecondaryAuthenticationFactorFinishAuthenticationStatus authStatus = await authResult.Authentication.FinishAuthenticationAsync(deviceHmac,
sessionHmac);
if (authStatus != SecondaryAuthenticationFactorFinishAuthenticationStatus.Completed)
{
ShowToastNotification("Unable to complete authentication!");
throw new Exception("Unable to complete authentication!");
}
ShowToastNotification("Auth completed");
}