extended implementation of OTP

src/Kp2aBusinessLogic/Io/CachingFileStorage.cs

@@ -60,7 +60,7 @@ namespace keepass2android.Io
 	/// </summary>
 	public class CachingFileStorage: IFileStorage
 	{
-		private readonly IFileStorage _cachedStorage;
+		protected readonly IFileStorage _cachedStorage;
 		private readonly ICacheSupervisor _cacheSupervisor;
 		private readonly string _streamCacheDir;
 
@@ -179,14 +179,21 @@ namespace keepass2android.Io
 				{
 					if (TryUpdateRemoteFile(localData, ioc, true, hash))
 						_cacheSupervisor.UpdatedRemoteFileOnLoad(ioc);
+					return File.OpenRead(cachedFilePath);
 				}
 			}
 			else
 			{
 				//conflict: both files changed.
-				//signal that we're loading from local
+				return OpenFileForReadWithConflict(ioc, cachedFilePath);
-				_cacheSupervisor.NotifyOpenFromLocalDueToConflict(ioc);
 			}
+			
+		}
+
+		protected virtual Stream OpenFileForReadWithConflict(IOConnectionInfo ioc, string cachedFilePath)
+		{
+			//signal that we're loading from local
+			_cacheSupervisor.NotifyOpenFromLocalDueToConflict(ioc);
 			return File.OpenRead(cachedFilePath);
 		}
 
@@ -214,29 +221,17 @@ namespace keepass2android.Io
 
 		private Stream OpenFileForReadWhenNoLocalChanges(IOConnectionInfo ioc, string cachedFilePath)
 		{
-			//open stream:
+
-			using (Stream file = _cachedStorage.OpenFileForRead(ioc))
+			//remember current hash
-			{
+			string previousHash = null;
+			string baseVersionFilePath = BaseVersionFilePath(ioc);
+			if (File.Exists(baseVersionFilePath))
+				previousHash = File.ReadAllText(baseVersionFilePath);
+
+
+
 				//copy to cache: 
-				//note: we might use the file version to check if it's already in the cache and if copying is required. 
+				var fileHash = UpdateCacheFromRemote(ioc, cachedFilePath);
-				//However, this is safer.
-				string fileHash;
-				using (HashingStreamEx cachedFile = new HashingStreamEx(File.Create(cachedFilePath), true, new SHA256Managed()))
-				{
-					file.CopyTo(cachedFile);
-					cachedFile.Close();
-					fileHash = MemUtil.ByteArrayToHexString(cachedFile.Hash);
-				}
-
-				//remember current hash
-				string previousHash = null;
-				string baseVersionFilePath = BaseVersionFilePath(ioc);
-				if (File.Exists(baseVersionFilePath))
-					previousHash = File.ReadAllText(baseVersionFilePath);
-
-				//save hash in cache files:
-				File.WriteAllText(VersionFilePath(ioc), fileHash);
-				File.WriteAllText(baseVersionFilePath, fileHash);
 
 				//notify supervisor what we did:
 				if (previousHash != fileHash)
@@ -245,8 +240,35 @@ namespace keepass2android.Io
 					_cacheSupervisor.LoadedFromRemoteInSync(ioc);
 
 				return File.OpenRead(cachedFilePath);	
+
+			
+		}
+
+		/// <summary>
+		/// copies the file in ioc to the local cache. Updates the cache version files and returns the new file hash.
+		/// </summary>
+		protected string UpdateCacheFromRemote(IOConnectionInfo ioc, string cachedFilePath)
+		{
+			//note: we might use the file version to check if it's already in the cache and if copying is required. 
+			//However, this is safer.
+			string fileHash;
+			
+			//open stream:
+			using (Stream remoteFile = _cachedStorage.OpenFileForRead(ioc))
+			{
+
+				using (HashingStreamEx cachedFile = new HashingStreamEx(File.Create(cachedFilePath), true, new SHA256Managed()))
+				{
+					remoteFile.CopyTo(cachedFile);
+					cachedFile.Close();
+					fileHash = MemUtil.ByteArrayToHexString(cachedFile.Hash);
+				}
 			}
 
+			//save hash in cache files:
+			File.WriteAllText(VersionFilePath(ioc), fileHash);
+			File.WriteAllText(BaseVersionFilePath(ioc), fileHash);
+			return fileHash;
 		}
 
 		private bool TryUpdateRemoteFile(Stream cachedData, IOConnectionInfo ioc, bool useFileTransaction, string hash)
@@ -266,7 +288,7 @@ namespace keepass2android.Io
 			}
 		}
 
-		private void UpdateRemoteFile(Stream cachedData, IOConnectionInfo ioc, bool useFileTransaction, string hash)
+		protected void UpdateRemoteFile(Stream cachedData, IOConnectionInfo ioc, bool useFileTransaction, string hash)
 		{
 			//try to write to remote:
 			using (

src/Kp2aBusinessLogic/UiStringKey.cs

@@ -44,6 +44,8 @@ namespace keepass2android
 		CheckingDatabaseForChanges,
 		RemoteDatabaseUnchanged,
 		CannotMoveGroupHere,
-		ErrorOcurred
+		ErrorOcurred,
+		SynchronizingOtpAuxFile,
+		SavingOtpAuxFile
     }
 }

src/Kp2aBusinessLogic/database/Database.cs

@@ -44,6 +44,13 @@ namespace keepass2android
 				return KpDatabase == null ? null : KpDatabase.IOConnectionInfo;
 			}
 		}
+
+		/// <summary>
+		/// if an OTP key was used, this property tells the location of the OTP auxiliary file.
+		/// Must be set after loading.
+		/// </summary>
+		public IOConnectionInfo OtpAuxFileIoc { get; set; }
+
 		public string LastFileVersion;
 		public SearchDbHelper SearchHelper;
 		
@@ -192,6 +199,7 @@ namespace keepass2android
 			KpDatabase = null;
 			_loaded = false;
 			_reloadRequested = false;
+			OtpAuxFileIoc = null;
 		}
 		
 		public void MarkAllGroupsAsDirty() {

src/keepass2android/GroupBaseActivity.cs

@@ -25,6 +25,7 @@ using Android.Widget;
 using KeePassLib;
 using Android.Preferences;
 using KeePassLib.Interfaces;
+using KeePassLib.Serialization;
 using KeePassLib.Utility;
 using keepass2android.Io;
 using keepass2android.database.edit;
@@ -367,6 +368,37 @@ namespace keepass2android
 			return base.OnOptionsItemSelected(item);
 		}
 
+		class SyncOtpAuxFile: OnFinish
+		{
+			private readonly IOConnectionInfo _ioc;
+
+			public SyncOtpAuxFile(IOConnectionInfo ioc)
+			{
+				_ioc = ioc;
+			}
+
+			public override void Run()
+			{
+				if (Handler != null)
+				{
+					Handler.Post(DoSyncOtpAuxFile);
+				}
+				else
+					DoSyncOtpAuxFile();
+				base.Run();
+			}
+
+			private void DoSyncOtpAuxFile()
+			{
+				StatusLogger.UpdateMessage(UiStringKey.SynchronizingOtpAuxFile);
+				//simply open the file. The file storage does a complete sync.
+				using (App.Kp2a.GetOtpAuxFileStorage(_ioc).OpenFileForRead(_ioc))
+				{
+					
+				}
+			}
+		}
+
 		private void Synchronize()
 		{
 			var filestorage = App.Kp2a.GetFileStorage(App.Kp2a.GetDb().Ioc);

src/keepass2android/NfcOtpActivity.cs

@@ -3,6 +3,7 @@ using Android.App;
 using Android.Content;
 using Android.Content.PM;
 using Android.OS;
+using Android.Widget;
 using Java.Util.Regex;
 
 namespace keepass2android
@@ -54,8 +55,30 @@ namespace keepass2android
 			
 			
 			i.SetFlags(ActivityFlags.NewTask | ActivityFlags.SingleTop | ActivityFlags.ClearTop);
-			i.PutExtra(Intents.OtpExtraKey, GetOtpFromIntent(Intent));
+			try
-			StartActivity(i);
+			{
+				string otp = GetOtpFromIntent(Intent);
+				if (otp == null)
+					throw new Exception("Otp must not be null!");
+				i.PutExtra(Intents.OtpExtraKey, otp);
+			}
+			catch (Exception e)
+			{
+				Kp2aLog.Log(e.ToString());
+				Toast.MakeText(this, "No Yubikey OTP found!", ToastLength.Long).Show();
+				Finish();
+				return;
+			}
+
+			if (App.Kp2a.GetDb().Loaded)
+			{
+				Toast.MakeText(this, GetString(Resource.String.otp_discarded_because_db_open), ToastLength.Long).Show();
+			}
+			else
+			{
+				StartActivity(i);				
+			}
+
 			Finish();
 
 		}

src/keepass2android/PasswordActivity.cs

@@ -17,7 +17,10 @@ This file is part of Keepass2Android, Copyright 2013 Philipp Crocoll. This file
 
 using System;
 using System.Collections.Generic;
+using System.IO;
 using System.Threading.Tasks;
+using System.Xml;
+using System.Xml.Serialization;
 using Android.App;
 using Android.Content;
 using Android.Database;
@@ -27,15 +30,17 @@ using Android.Views;
 using Android.Widget;
 using Java.Net;
 using Android.Preferences;
-using Java.IO;
 using Android.Text;
 using Android.Content.PM;
 using KeePassLib.Keys;
 using KeePassLib.Serialization;
+using KeePassLib.Utility;
 using OtpKeyProv;
 using keepass2android.Io;
 using keepass2android.Utils;
 using Exception = System.Exception;
+using File = Java.IO.File;
+using FileNotFoundException = Java.IO.FileNotFoundException;
 using MemoryStream = System.IO.MemoryStream;
 using Object = Java.Lang.Object;
 using Process = Android.OS.Process;
@@ -55,11 +60,10 @@ namespace keepass2android
 			//int values correspond to indices in passwordSpinner
 			None = 0,
 			KeyFile = 1,
-			Otp = 2
+			Otp = 2,
+			OtpRecovery = 3
 		}
 
-		bool _showPassword;
-
 		public const String KeyDefaultFilename = "defaultFileName";
 
 		public const String KeyFilename = "fileName";
@@ -71,19 +75,23 @@ namespace keepass2android
 		private const String ViewIntent = "android.intent.action.VIEW";
 		private const string ShowpasswordKey = "ShowPassword";
 		private const string KeyProviderIdOtp = "KP2A-OTP";
+		private const string KeyProviderIdOtpRecovery = "KP2A-OTPSecret";
+
+		private const int RequestCodePrepareDbFile = 1000;
+		private const int RequestCodePrepareOtpAuxFile = 1001;
+
 
 		private Task<MemoryStream> _loadDbTask;
 		private IOConnectionInfo _ioConnection;
 		private String _keyFileOrProvider;
+		bool _showPassword;
 
 		internal AppTask AppTask;
 		private bool _killOnDestroy;
 		private string _password = "";
 		//OTPs which should be entered into the OTP fields as soon as these become visible
-		private readonly List<String> _pendingOtps = new List<string>();
+		private List<String> _pendingOtps = new List<string>();
 
-		private const int RequestCodePrepareDbFile = 1000;
-		private const int RequestCodePrepareOtpAuxFile = 1001;
 
 
 		KeyProviders KeyProviderType
@@ -94,6 +102,8 @@ namespace keepass2android
 					return KeyProviders.None;
 				if (_keyFileOrProvider == KeyProviderIdOtp)
 					return KeyProviders.Otp;
+				if (_keyFileOrProvider == KeyProviderIdOtpRecovery)
+					return KeyProviders.OtpRecovery;
 				return KeyProviders.KeyFile;
 			}
 		}
@@ -103,7 +113,12 @@ namespace keepass2android
 
 		private bool _starting;
 		private OtpInfo _otpInfo;
-		private readonly int[] _otpTextViewIds = new int[] {Resource.Id.otp1, Resource.Id.otp2, Resource.Id.otp3, Resource.Id.otp4, Resource.Id.otp5, Resource.Id.otp6};
+		private readonly int[] _otpTextViewIds = new[] {Resource.Id.otp1, Resource.Id.otp2, Resource.Id.otp3, Resource.Id.otp4, Resource.Id.otp5, Resource.Id.otp6};
+		private const string OtpInfoKey = "OtpInfoKey";
+		private const string EnteredOtpsKey = "EnteredOtpsKey";
+		private const string PendingOtpsKey = "PendingOtpsKey";
+		private const string PasswordKey = "PasswordKey";
+		private const string KeyFileOrProviderKey = "KeyFileOrProviderKey";
 
 		public PasswordActivity (IntPtr javaReference, JniHandleOwnership transfer)
 			: base(javaReference, transfer)
@@ -217,7 +232,7 @@ namespace keepass2android
 							KcpKeyFile kcpKeyfile = (KcpKeyFile)App.Kp2a.GetDb().KpDatabase.MasterKey.GetUserKey(typeof(KcpKeyFile));
 
 							SetEditText(Resource.Id.pass_keyfile, kcpKeyfile.Path);
-							_keyFileOrProvider = kcpKeyfile.Path;
+							
 						}
 					}
 					App.Kp2a.LockDatabase(false);
@@ -234,7 +249,7 @@ namespace keepass2android
 							
 							EditText fn = (EditText) FindViewById(Resource.Id.pass_keyfile);
 							fn.Text = filename;
-							_keyFileOrProvider = filename;
+							
 						}
 					}
 					break;
@@ -265,51 +280,54 @@ namespace keepass2android
 							Toast.MakeText(this, GetString(Resource.String.CouldntLoadOtpAuxFile), ToastLength.Long).Show();
 							return;
 						}
-						FindViewById(Resource.Id.otpInitView).Visibility = ViewStates.Gone;
-						FindViewById(Resource.Id.otpEntry).Visibility = ViewStates.Visible;
-						int c = 0;
 
-						foreach (int otpId in _otpTextViewIds)
+						IList<string> prefilledOtps = _pendingOtps;
-						{
+						ShowOtpEntry(prefilledOtps);
-							c++;
-							var otpTextView = FindViewById<EditText>(otpId);
-							if (c <= _pendingOtps.Count)
-							{
-								otpTextView.Text = _pendingOtps[c-1];
-							}
-							else
-							{
-								otpTextView.Text = "";
-							}
-							otpTextView.Hint = GetString(Resource.String.otp_hint, new Object[] {c});
-							otpTextView.SetFilters(new IInputFilter[] {new InputFilterLengthFilter((int)_otpInfo.OtpLength) });
-							if (c > _otpInfo.OtpsRequired)
-							{
-								otpTextView.Visibility = ViewStates.Gone;
-							}
-							else
-							{
-								otpTextView.TextChanged += (sender, args) => 
-								{
-									UpdateOkButtonState();
-								};
-							}
-						}
 						_pendingOtps.Clear();
 						
 					}
 			).Execute();
 		}
 
+		private void ShowOtpEntry(IList<string> prefilledOtps)
+		{
+			FindViewById(Resource.Id.otpInitView).Visibility = ViewStates.Gone;
+			FindViewById(Resource.Id.otpEntry).Visibility = ViewStates.Visible;
+			int c = 0;
+
+			foreach (int otpId in _otpTextViewIds)
+			{
+				c++;
+				var otpTextView = FindViewById<EditText>(otpId);
+				if (c <= prefilledOtps.Count)
+				{
+					otpTextView.Text = prefilledOtps[c - 1];
+				}
+				else
+				{
+					otpTextView.Text = "";
+				}
+				otpTextView.Hint = GetString(Resource.String.otp_hint, new Object[] {c});
+				otpTextView.SetFilters(new IInputFilter[] {new InputFilterLengthFilter((int) _otpInfo.OtpLength)});
+				if (c > _otpInfo.OtpsRequired)
+				{
+					otpTextView.Visibility = ViewStates.Gone;
+				}
+				else
+				{
+					otpTextView.TextChanged += (sender, args) => { UpdateOkButtonState(); };
+				}
+			}
+		}
+
 		protected override void OnCreate(Bundle savedInstanceState)
 		{
 			base.OnCreate(savedInstanceState);
-			if (savedInstanceState != null)
+
-				_showPassword = savedInstanceState.GetBoolean(ShowpasswordKey, false);
+			Intent i = Intent;
 
 			AppTask = AppTask.GetTaskInOnCreate(savedInstanceState, Intent);
 
-			Intent i = Intent;
 			String action = i.Action;
 			
 			_prefs = PreferenceManager.GetDefaultSharedPreferences(this);
@@ -320,84 +338,11 @@ namespace keepass2android
 
 			if (action != null && action.Equals(ViewIntent))
 			{
-				//started from "view" intent (e.g. from file browser)
+				if (!GetIocFromViewIntent(i)) return;
-				_ioConnection.Path = i.DataString;
-				
-				if (! _ioConnection.Path.Substring(0, 7).Equals("file://"))
-				{
-					//TODO: this might no longer be required as we can handle http(s) and ftp as well (but we need server credentials therefore)
-					Toast.MakeText(this, Resource.String.error_can_not_handle_uri, ToastLength.Long).Show();
-					Finish();
-					return;
-				}
-
-				_ioConnection.Path = URLDecoder.Decode(_ioConnection.Path.Substring(7));
-				
-				if (_ioConnection.Path.Length == 0)
-				{
-					// No file name
-					Toast.MakeText(this, Resource.String.FileNotFound, ToastLength.Long).Show();
-					Finish();
-					return;
-				}
-
-				File dbFile = new File(_ioConnection.Path);
-				if (! dbFile.Exists())
-				{
-					// File does not exist
-					Toast.MakeText(this, Resource.String.FileNotFound, ToastLength.Long).Show();
-					Finish();
-					return;
-				}
-				
-				_keyFileOrProvider = GetKeyFile(_ioConnection.Path);
-				
 			} 
 			else if ((action != null) && (action.Equals(Intents.StartWithOtp)))
 			{
-				//create called after detecting an OTP via NFC
+				if (!GetIocFromOtpIntent(savedInstanceState, i)) return;
-				//this means the Activity was not on the back stack before, i.e. no database has been selected
-
-				_ioConnection = null;
-
-				//see if we can get a database from recent:
-				if (App.Kp2a.FileDbHelper.HasRecentFiles())
-				{
-					ICursor filesCursor = App.Kp2a.FileDbHelper.FetchAllFiles();
-					StartManagingCursor(filesCursor);
-					filesCursor.MoveToFirst();
-					IOConnectionInfo ioc = App.Kp2a.FileDbHelper.CursorToIoc(filesCursor);
-					if (App.Kp2a.GetFileStorage(ioc).RequiresSetup(ioc) == false)
-					{
-						IFileStorage fileStorage = App.Kp2a.GetFileStorage(ioc);
-
-						if (!fileStorage.RequiresCredentials(ioc))
-						{
-							//ok, we can use this file
-							_ioConnection = ioc;
-
-						}
-					}
-				}
-
-				if (_ioConnection == null)
-				{
-					//We need to go to FileSelectActivity first.
-					//For security reasons: discard the OTP (otherwise the user might not select a database now and forget 
-					//about the OTP, but it would still be stored in the Intents and later be passed to PasswordActivity again.
-
-					Toast.MakeText(this, GetString(Resource.String.otp_discarded_because_no_db), ToastLength.Long).Show();
-					GoToFileSelectActivity();
-					Finish();
-					return;
-				}
-
-				//user obviously wants to use OTP:
-				_keyFileOrProvider = KeyProviderIdOtp;
-
-				//remember the OTP for later use
-				_pendingOtps.Add(Intent.GetStringExtra(Intents.OtpExtraKey));
-				Intent.RemoveExtra(Intents.OtpExtraKey);
 			}
 			else
 			{
@@ -419,16 +364,17 @@ namespace keepass2android
 			
 			
 			SetContentView(Resource.Layout.password);
-			PopulateView();
+			InitializeFilenameView();
 
-			EditText passwordEdit = FindViewById<EditText>(Resource.Id.password);
+			if (KeyProviderType == KeyProviders.KeyFile)
+				SetEditText(Resource.Id.pass_keyfile, _keyFileOrProvider);
 
 			FindViewById<EditText>(Resource.Id.pass_keyfile).TextChanged +=
 				(sender, args) =>
-					{
+				{
-						_keyFileOrProvider = FindViewById<EditText>(Resource.Id.pass_keyfile).Text;
+					_keyFileOrProvider = FindViewById<EditText>(Resource.Id.pass_keyfile).Text;
-						UpdateOkButtonState();
+					UpdateOkButtonState();
-					};
+				};
 
 			FindViewById<EditText>(Resource.Id.password).TextChanged +=
 				(sender, args) =>
@@ -437,20 +383,167 @@ namespace keepass2android
 					UpdateOkButtonState();
 				};
 
+			FindViewById<EditText>(Resource.Id.pass_otpsecret).TextChanged += (sender, args) => UpdateOkButtonState();
+
+
+			EditText passwordEdit = FindViewById<EditText>(Resource.Id.password);
 			passwordEdit.RequestFocus();
 			Window.SetSoftInputMode(SoftInput.StateVisible);
 
-			Button confirmButton = (Button)FindViewById(Resource.Id.pass_ok);
+			InitializeOkButton();
+
+			InitializePasswordModeSpinner();
+
+			InitializeOtpSecretSpinner();
+
+			UpdateOkButtonState();
+			
+			InitializeTogglePasswordButton();
+			InitializeKeyfileBrowseButton();
+
+			InitializeQuickUnlockCheckbox();
+
+			RestoreState(savedInstanceState);
+		}
+
+		private void InitializeOtpSecretSpinner()
+		{
+			Spinner spinner = FindViewById<Spinner>(Resource.Id.otpsecret_format_spinner);
+			ArrayAdapter<String> spinnerArrayAdapter = new ArrayAdapter<String>(this, Android.Resource.Layout.SimpleSpinnerDropDownItem, EncodingUtil.Formats);
+			spinner.Adapter = spinnerArrayAdapter;
+		}
+
+		private bool GetIocFromOtpIntent(Bundle savedInstanceState, Intent i)
+		{
+			//create called after detecting an OTP via NFC
+			//this means the Activity was not on the back stack before, i.e. no database has been selected
+
+			_ioConnection = null;
+
+			//see if we can get a database from recent:
+			if (App.Kp2a.FileDbHelper.HasRecentFiles())
+			{
+				ICursor filesCursor = App.Kp2a.FileDbHelper.FetchAllFiles();
+				StartManagingCursor(filesCursor);
+				filesCursor.MoveToFirst();
+				IOConnectionInfo ioc = App.Kp2a.FileDbHelper.CursorToIoc(filesCursor);
+				if (App.Kp2a.GetFileStorage(ioc).RequiresSetup(ioc) == false)
+				{
+					IFileStorage fileStorage = App.Kp2a.GetFileStorage(ioc);
+
+					if (!fileStorage.RequiresCredentials(ioc))
+					{
+						//ok, we can use this file
+						_ioConnection = ioc;
+					}
+				}
+			}
+
+			if (_ioConnection == null)
+			{
+				//We need to go to FileSelectActivity first.
+				//For security reasons: discard the OTP (otherwise the user might not select a database now and forget 
+				//about the OTP, but it would still be stored in the Intents and later be passed to PasswordActivity again.
+
+				Toast.MakeText(this, GetString(Resource.String.otp_discarded_because_no_db), ToastLength.Long).Show();
+				GoToFileSelectActivity();
+				Finish();
+				return false;
+			}
+
+			//user obviously wants to use OTP:
+			_keyFileOrProvider = KeyProviderIdOtp;
+
+			if (savedInstanceState == null) //only when not re-creating
+			{
+				//remember the OTP for later use
+				_pendingOtps.Add(i.GetStringExtra(Intents.OtpExtraKey));
+				i.RemoveExtra(Intents.OtpExtraKey);
+			}
+			return true;
+		}
+
+		private bool GetIocFromViewIntent(Intent i)
+		{
+			//started from "view" intent (e.g. from file browser)
+			_ioConnection.Path = i.DataString;
+
+			if (! _ioConnection.Path.Substring(0, 7).Equals("file://"))
+			{
+				//TODO: this might no longer be required as we can handle http(s) and ftp as well (but we need server credentials therefore)
+				Toast.MakeText(this, Resource.String.error_can_not_handle_uri, ToastLength.Long).Show();
+				Finish();
+				return false;
+			}
+
+			_ioConnection.Path = URLDecoder.Decode(_ioConnection.Path.Substring(7));
+
+			if (_ioConnection.Path.Length == 0)
+			{
+				// No file name
+				Toast.MakeText(this, Resource.String.FileNotFound, ToastLength.Long).Show();
+				Finish();
+				return false;
+			}
+
+			File dbFile = new File(_ioConnection.Path);
+			if (! dbFile.Exists())
+			{
+				// File does not exist
+				Toast.MakeText(this, Resource.String.FileNotFound, ToastLength.Long).Show();
+				Finish();
+				return false;
+			}
+
+			_keyFileOrProvider = GetKeyFile(_ioConnection.Path);
+			return true;
+		}
+
+		private void InitializeOkButton()
+		{
+			Button confirmButton = (Button) FindViewById(Resource.Id.pass_ok);
 			confirmButton.Click += (sender, e) =>
 				{
 					App.Kp2a.GetFileStorage(_ioConnection)
-					   .PrepareFileUsage(new FileStorageSetupInitiatorActivity(this, OnActivityResult, null), _ioConnection, RequestCodePrepareDbFile, false);
+					   .PrepareFileUsage(new FileStorageSetupInitiatorActivity(this, OnActivityResult, null), _ioConnection,
+					                     RequestCodePrepareDbFile, false);
 				};
+		}
 
+		private void InitializeTogglePasswordButton()
+		{
+			ImageButton btnTogglePassword = (ImageButton) FindViewById(Resource.Id.toggle_password);
+			btnTogglePassword.Click += (sender, e) =>
+				{
+					_showPassword = !_showPassword;
+					MakePasswordMaskedOrVisible();
+				};
+		}
+
+		private void InitializeKeyfileBrowseButton()
+		{
+			ImageButton browse = (ImageButton) FindViewById(Resource.Id.browse_button);
+			browse.Click += (sender, evt) =>
+				{
+					string filename = null;
+					if (!String.IsNullOrEmpty(_ioConnection.Path))
+					{
+						File keyfile = new File(_ioConnection.Path);
+						File parent = keyfile.ParentFile;
+						if (parent != null)
+						{
+							filename = parent.AbsolutePath;
+						}
+					}
+					Util.ShowBrowseDialog(filename, this, Intents.RequestCodeFileBrowseForKeyfile, false);
+				};
+		}
+
+		private void InitializePasswordModeSpinner()
+		{
 			Spinner passwordModeSpinner = FindViewById<Spinner>(Resource.Id.password_mode_spinner);
 			if (passwordModeSpinner != null)
 			{
-
 				UpdateKeyProviderUiState();
 				passwordModeSpinner.SetSelection((int) KeyProviderType);
 				passwordModeSpinner.ItemSelected += (sender, args) =>
@@ -466,16 +559,20 @@ namespace keepass2android
 							case 2:
 								_keyFileOrProvider = KeyProviderIdOtp;
 								break;
+							case 3:
+								_keyFileOrProvider = KeyProviderIdOtpRecovery;
+								break;
 							default:
-								throw new Exception("Unexpected position "+args.Position+" / " + ((ICursor)((AdapterView)sender).GetItemAtPosition(args.Position)).GetString(1));
+								throw new Exception("Unexpected position " + args.Position + " / " +
-
+								                    ((ICursor) ((AdapterView) sender).GetItemAtPosition(args.Position)).GetString(1));
 						}
 						UpdateKeyProviderUiState();
 					};
 				FindViewById(Resource.Id.init_otp).Click += (sender, args) =>
 					{
 						App.Kp2a.GetOtpAuxFileStorage(_ioConnection)
-						.PrepareFileUsage(new FileStorageSetupInitiatorActivity(this, OnActivityResult, null), _ioConnection, RequestCodePrepareOtpAuxFile, false);
+						   .PrepareFileUsage(new FileStorageSetupInitiatorActivity(this, OnActivityResult, null), _ioConnection,
+						                     RequestCodePrepareOtpAuxFile, false);
 					};
 			}
 			else
@@ -483,51 +580,35 @@ namespace keepass2android
 				//android 2.x 
 				//TODO test
 			}
+		}
 
-
+		private void RestoreState(Bundle savedInstanceState)
-			UpdateOkButtonState();
+		{
-			
+			if (savedInstanceState != null)
-			
-			
-			/*CheckBox checkBox = (CheckBox) FindViewById(Resource.Id.show_password);
-			// Show or hide password
-			checkBox.CheckedChange += delegate(object sender, CompoundButton.CheckedChangeEventArgs e) {
-
-				TextView password = (TextView) FindViewById(Resource.Id.password);
-				if ( e.IsChecked ) {
-					password.InputType = InputTypes.ClassText | InputTypes.TextVariationVisiblePassword;
-				} else {
-					password.InputType = InputTypes.ClassText | InputTypes.TextVariationPassword;
-				}
-			};
-			*/
-			ImageButton btnTogglePassword = (ImageButton)FindViewById(Resource.Id.toggle_password);
-			btnTogglePassword.Click += (sender, e) =>
-				{
-					_showPassword = !_showPassword;
-					MakePasswordMaskedOrVisible();
-				};
-			
-			
-			
-			ImageButton browse = (ImageButton)FindViewById(Resource.Id.browse_button);
-			browse.Click += (sender, evt) => 
 			{
-				string filename = null;
+				_showPassword = savedInstanceState.GetBoolean(ShowpasswordKey, false);
-				if (!String.IsNullOrEmpty(_ioConnection.Path))
+				MakePasswordMaskedOrVisible();
+
+				_keyFileOrProvider = FindViewById<EditText>(Resource.Id.pass_keyfile).Text = savedInstanceState.GetString(KeyFileOrProviderKey);
+				_password = FindViewById<EditText>(Resource.Id.password).Text = savedInstanceState.GetString(PasswordKey);
+
+				_pendingOtps = new List<string>(savedInstanceState.GetStringArrayList(PendingOtpsKey));
+				
+				string otpInfoString = savedInstanceState.GetString(OtpInfoKey);
+				if (otpInfoString != null)
 				{
-					File keyfile = new File(_ioConnection.Path);
+					
-					File parent = keyfile.ParentFile;
+					XmlSerializer xs = new XmlSerializer(typeof(OtpInfo));
-					if (parent != null)
+					_otpInfo = (OtpInfo)xs.Deserialize(new StringReader(otpInfoString));
-					{
+
-						filename = parent.AbsolutePath;
+					var enteredOtps = savedInstanceState.GetStringArrayList(EnteredOtpsKey);
-					}
+
+					ShowOtpEntry(enteredOtps);
 				}
-				Util.ShowBrowseDialog(filename, this, Intents.RequestCodeFileBrowseForKeyfile, false);
 				
-			};
+				UpdateKeyProviderUiState();
 				
-			RetrieveSettings();
+			}
 		}
 
 		private void UpdateOkButtonState()
@@ -562,6 +643,9 @@ namespace keepass2android
 					
 					FindViewById(Resource.Id.pass_ok).Enabled = enabled;
 					break;
+				case KeyProviders.OtpRecovery:
+					FindViewById(Resource.Id.pass_ok).Enabled = FindViewById<EditText>(Resource.Id.pass_otpsecret).Text != "" && _password != "";
+					break;
 				default:
 					throw new ArgumentOutOfRangeException();
 			}
@@ -575,6 +659,10 @@ namespace keepass2android
 			FindViewById(Resource.Id.otpView).Visibility = KeyProviderType == KeyProviders.Otp
 				                                               ? ViewStates.Visible
 				                                               : ViewStates.Gone;
+
+			FindViewById(Resource.Id.otpSecretLine).Visibility = KeyProviderType == KeyProviders.OtpRecovery
+															   ? ViewStates.Visible
+															   : ViewStates.Gone;
 			if (KeyProviderType == KeyProviders.Otp)
 			{
 				FindViewById(Resource.Id.otps_pending).Visibility = _pendingOtps.Count > 0 ? ViewStates.Visible : ViewStates.Gone;
@@ -597,7 +685,8 @@ namespace keepass2android
 				catch (Exception e)
 				{
 					Kp2aLog.Log(e.ToString());
-					throw new KeyFileException();
+					Toast.MakeText(this, App.Kp2a.GetResourceString(UiStringKey.keyfile_does_not_exist), ToastLength.Long).Show();
+					return;
 				}
 			}
 			else if (KeyProviderType == KeyProviders.Otp)
@@ -605,26 +694,34 @@ namespace keepass2android
 
 				try
 				{
-					List<string> lOtps = new List<string>();
+					var lOtps = GetOtpsFromUI();
-					foreach (int otpId in _otpTextViewIds)
-					{
-						string otpText = FindViewById<EditText>(otpId).Text;
-						if (!String.IsNullOrEmpty(otpText))
-							lOtps.Add(otpText);
-					}
 					CreateOtpSecret(lOtps);
 				}
 				catch (Exception)
 				{
-					const string strMain = "Failed to create OTP key!";
-					const string strLine1 = "Make sure you've entered the correct OTPs.";
 
-					Toast.MakeText(this, strMain + " " + strLine1, ToastLength.Long).Show();
+					Toast.MakeText(this, GetString(Resource.String.OtpKeyError), ToastLength.Long).Show();
 
 					return;
 				}
 				compositeKey.AddUserKey(new KcpCustomKey(OathHotpKeyProv.Name, _otpInfo.Secret, true));
 			}
+			else if (KeyProviderType == KeyProviders.OtpRecovery)
+			{
+				Spinner stpDataFmtSpinner = FindViewById<Spinner>(Resource.Id.otpsecret_format_spinner);
+				EditText secretEdit = FindViewById<EditText>(Resource.Id.pass_otpsecret);
+
+				byte[] pbSecret = EncodingUtil.ParseKey(secretEdit.Text, (OtpDataFmt)stpDataFmtSpinner.SelectedItemPosition);
+				if (pbSecret != null)
+				{
+					compositeKey.AddUserKey(new KcpCustomKey(OathHotpKeyProv.Name, pbSecret, true));
+				}
+				else
+				{
+					Toast.MakeText(this, Resource.String.CouldntParseOtpSecret, ToastLength.Long).Show();
+					return;
+				}
+			}
 
 			CheckBox cbQuickUnlock = (CheckBox) FindViewById(Resource.Id.enable_quickunlock);
 			App.Kp2a.SetQuickUnlockEnabled(cbQuickUnlock.Checked);
@@ -642,6 +739,18 @@ namespace keepass2android
 			new ProgressTask(App.Kp2a, this, task).Run();
 		}
 
+		private List<string> GetOtpsFromUI()
+		{
+			List<string> lOtps = new List<string>();
+			foreach (int otpId in _otpTextViewIds)
+			{
+				string otpText = FindViewById<EditText>(otpId).Text;
+				if (!String.IsNullOrEmpty(otpText))
+					lOtps.Add(otpText);
+			}
+			return lOtps;
+		}
+
 		private void CreateOtpSecret(List<string> lOtps)
 		{
 			byte[] pbSecret;
@@ -785,13 +894,32 @@ namespace keepass2android
 			base.OnSaveInstanceState(outState);
 			AppTask.ToBundle(outState);
 			outState.PutBoolean(ShowpasswordKey, _showPassword);
-			//TODO: 
+
-			// * save OTP state
+			outState.PutString(KeyFileOrProviderKey, _keyFileOrProvider);
+			outState.PutString(PasswordKey, _password);
+			outState.PutStringArrayList(PendingOtpsKey, _pendingOtps);
+			if (_otpInfo != null)
+			{
+				outState.PutStringArrayList(EnteredOtpsKey, GetOtpsFromUI());
+
+				var sw = new StringWriter();
+
+				var xws = OtpInfo.XmlWriterSettings();
+
+				XmlWriter xw = XmlWriter.Create(sw, xws);
+
+				XmlSerializer xs = new XmlSerializer(typeof(OtpInfo));
+				xs.Serialize(xw, _otpInfo);
+
+				xw.Close();
+
+				outState.PutString(OtpInfoKey, sw.ToString());
+			}
 			
 			//more OTP TODO:
-			// * NfcOtp: Ask for close when db open
 			// * Caching of aux file
 			// *  -> implement IFileStorage in JavaFileStorage based on ListFiles
+			// *  -> Sync
 		}
 
 		protected override void OnNewIntent(Intent intent)
@@ -896,7 +1024,7 @@ namespace keepass2android
 			}
 		}
 		
-		private void RetrieveSettings() {
+		private void InitializeQuickUnlockCheckbox() {
 			CheckBox cbQuickUnlock = (CheckBox)FindViewById(Resource.Id.enable_quickunlock);
 			cbQuickUnlock.Checked = _prefs.GetBoolean(GetString(Resource.String.QuickUnlockDefaultEnabled_key), true);
 		}
@@ -909,7 +1037,7 @@ namespace keepass2android
 			}
 		}
 		
-		private void PopulateView() {
+		private void InitializeFilenameView() {
 			SetEditText(Resource.Id.filename, App.Kp2a.GetFileStorage(_ioConnection).GetDisplayName(_ioConnection));
 			if (App.Kp2a.FileDbHelper.NumberOfRecentFiles() < 2)
 			{
@@ -919,8 +1047,7 @@ namespace keepass2android
 			{
 				FindViewById(Resource.Id.filename_group).Visibility = ViewStates.Visible;
 			}
-			if (KeyProviderType == KeyProviders.KeyFile)
+			
-				SetEditText(Resource.Id.pass_keyfile, _keyFileOrProvider);
 		}
 
 		protected override void OnDestroy()
@@ -937,15 +1064,6 @@ namespace keepass2android
 	}
 	*/
 
-		private void ErrorMessage(int resId)
-		{
-			Toast.MakeText(this, resId, ToastLength.Long).Show();
-		}
-	
-		private String GetEditText(int resId) {
-			return Util.GetEditText(this, resId);
-		}
-		
 		private void SetEditText(int resId, String str) {
 			TextView te =  (TextView) FindViewById(resId);
 			//assert(te == null);
@@ -1002,13 +1120,40 @@ namespace keepass2android
 
 
 			public override void Run() {
+
+				if (_act.KeyProviderType == KeyProviders.Otp)
+				{
+					try
+					{
+						StatusLogger.UpdateMessage(UiStringKey.SavingOtpAuxFile);
+
+						if (!OathHotpKeyProv.CreateAuxFile(_act._otpInfo, new KeyProviderQueryContext(_act._ioConnection, false, false)))
+							Toast.MakeText(_act, _act.GetString(Resource.String.ErrorUpdatingOtpAuxFile), ToastLength.Long).Show();
+					}
+					catch (Exception e)
+					{
+						Kp2aLog.Log(e.Message);
+
+						Toast.MakeText(_act, _act.GetString(Resource.String.ErrorUpdatingOtpAuxFile)+" "+e.Message, ToastLength.Long).Show();
+					}
+				}
+				
+
 				if ( Success ) 
 				{
 					_act.SetEditText(Resource.Id.password, "");
+					_act.SetEditText(Resource.Id.pass_otpsecret, "");
+					foreach (int otpId in  _act._otpTextViewIds)
+					{
+						_act.SetEditText(otpId, "");
+					}
 
 					_act.LaunchNextActivity();
 
-					GC.Collect(); // Ensure temporary memory used while loading is collected - it will contain sensitive data such as username and password, and also the large data of the encrypted database file
+					if ((_act.KeyProviderType == KeyProviders.Otp) || (_act.KeyProviderType == KeyProviders.OtpRecovery))
+						App.Kp2a.GetDb().OtpAuxFileIoc = OathHotpKeyProv.GetAuxFileIoc(_act._ioConnection);
+
+					GC.Collect(); // Ensure temporary memory used while loading is collected
 				} 
 				else
 				{

src/keepass2android/Resources/layout-v14/password.xml

@@ -1,188 +1,213 @@
 <?xml version="1.0" encoding="utf-8"?>
-<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
-    android:layout_width="fill_parent"
+xmlns:tools="http://schemas.android.com/tools"
-    android:layout_height="wrap_content"
+android:layout_width="match_parent"
-    android:layout_marginLeft="12dip"
+android:layout_height="match_parent"
-    android:layout_marginRight="12dip"
+>
-    android:layout_marginBottom="12dip"
+	<LinearLayout
-	android:orientation="vertical"
-			  >
-	<RelativeLayout
-		android:id="@+id/filename_group"
 		android:layout_width="fill_parent"
-		android:layout_height="wrap_content">
+		android:layout_height="match_parent"
-		<TextView
-			android:id="@+id/filename_label"
-			android:layout_width="wrap_content"
-			android:layout_height="wrap_content"
-			style="@style/TextAppearance_SmallHeading"
-			android:text="@string/pass_filename" />
-		<ImageView
-			android:id="@+id/divider1"
-			android:layout_width="fill_parent"
-			android:layout_height="wrap_content"
-			android:layout_below="@id/filename_label"
-			android:scaleType="fitXY"
-			android:src="@android:drawable/divider_horizontal_dark" />
-		<HorizontalScrollView
-			android:id="@+id/filenamescroll"
-			android:layout_width="fill_parent"
-			android:layout_height="wrap_content"
-			android:layout_below="@id/divider1">
-			<TextView
-				android:id="@+id/filename"
-				style="@style/GroupText"
-				android:layout_width="fill_parent"
-				android:layout_height="wrap_content"
-				android:singleLine="true"
-				android:ellipsize="none"
-				android:focusable="true"
-				android:focusableInTouchMode="true" />
-		</HorizontalScrollView>
-		<ImageView
-			android:id="@+id/divider2"
-			android:layout_width="fill_parent"
-			android:layout_height="wrap_content"
-			android:layout_below="@id/filenamescroll"
-			android:scaleType="fitXY"
-			android:src="@android:drawable/divider_horizontal_dark" />
-	</RelativeLayout>
-    <TextView
-        android:id="@+id/password_label"
-        android:layout_width="wrap_content"
-        android:layout_height="wrap_content"
-        android:text="" />
-	<Spinner
-    android:id="@+id/password_mode_spinner"
-    android:layout_width="fill_parent"
-    android:layout_height="wrap_content" 
-	android:entries="@array/password_modes"
-	/>
-
-	<LinearLayout
-        android:id="@+id/passwordLine"
-        android:layout_width="fill_parent"
-        android:layout_height="wrap_content"
-        android:orientation="horizontal">
-        <EditText
-            android:id="@+id/password"
-            android:layout_width="0px"
-            android:layout_height="wrap_content"
-            android:singleLine="true"
-            android:inputType="textPassword"
-            android:layout_weight="1"
-            android:hint="@string/hint_login_pass" />
-        <ImageButton
-            android:id="@+id/toggle_password"
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:src="@drawable/ic_menu_view" />
-    </LinearLayout>
-	<LinearLayout
-        android:id="@+id/keyfileLine"
-        android:layout_width="fill_parent"
-        android:layout_height="wrap_content"
-        android:orientation="horizontal">
-        <EditText
-            android:id="@+id/pass_keyfile"
-            android:layout_width="0px"
-            android:layout_height="wrap_content"
-            android:singleLine="true"
-            android:layout_weight="1"
-            android:hint="@string/entry_keyfile" />
-        <ImageButton
-            android:id="@+id/browse_button"
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:src="@drawable/ic_launcher_folder_small" />
-    </LinearLayout>
-	<LinearLayout
-        android:id="@+id/otpView"
 		android:layout_marginLeft="12dip"
 		android:layout_marginRight="12dip"
-        android:layout_width="fill_parent"
+		android:layout_marginBottom="12dip"
-        android:layout_height="wrap_content"
 		android:orientation="vertical"
-		>
+			  >
-		<LinearLayout
+		<RelativeLayout
-        android:id="@+id/otpInitView"
+			android:id="@+id/filename_group"
+			android:layout_width="fill_parent"
+			android:layout_height="wrap_content">
+			<TextView
+				android:id="@+id/filename_label"
+				android:layout_width="wrap_content"
+				android:layout_height="wrap_content"
+				style="@style/TextAppearance_SmallHeading"
+				android:text="@string/pass_filename" />
+			<ImageView
+				android:id="@+id/divider1"
+				android:layout_width="fill_parent"
+				android:layout_height="wrap_content"
+				android:layout_below="@id/filename_label"
+				android:scaleType="fitXY"
+				android:src="@android:drawable/divider_horizontal_dark" />
+			<HorizontalScrollView
+				android:id="@+id/filenamescroll"
+				android:layout_width="fill_parent"
+				android:layout_height="wrap_content"
+				android:layout_below="@id/divider1">
+				<TextView
+					android:id="@+id/filename"
+					style="@style/GroupText"
+					android:layout_width="fill_parent"
+					android:layout_height="wrap_content"
+					android:singleLine="true"
+					android:ellipsize="none"
+					android:focusable="true"
+					android:focusableInTouchMode="true" />
+			</HorizontalScrollView>
+			<ImageView
+				android:id="@+id/divider2"
+				android:layout_width="fill_parent"
+				android:layout_height="wrap_content"
+				android:layout_below="@id/filenamescroll"
+				android:scaleType="fitXY"
+				android:src="@android:drawable/divider_horizontal_dark" />
+		</RelativeLayout>
+		<TextView
+			android:id="@+id/password_label"
+			android:layout_width="wrap_content"
+			android:layout_height="wrap_content"
+			android:text="@string/master_key_type" />
+		<Spinner
+		android:id="@+id/password_mode_spinner"
 		android:layout_width="fill_parent"
-        android:layout_height="wrap_content"
+		android:layout_height="wrap_content"
-		>
+		android:entries="@array/password_modes"
-			<Button
+	/>
-			android:id="@+id/init_otp"
+
-			android:text="@string/init_otp"
+		<LinearLayout
-			android:layout_width="wrap_content"
+			android:id="@+id/passwordLine"
-			android:layout_height="wrap_content"/>
+			android:layout_width="fill_parent"
-			<TextView
+			android:layout_height="wrap_content"
-				android:id="@+id/otps_pending"
+			android:orientation="horizontal">
-			android:text="@string/otps_pending"
+			<EditText
-			android:layout_width="wrap_content"
+				android:id="@+id/password"
-			android:layout_height="wrap_content" />
+				android:layout_width="0px"
+				android:layout_height="wrap_content"
+				android:singleLine="true"
+				android:inputType="textPassword"
+				android:layout_weight="1"
+				android:hint="@string/hint_login_pass" />
+			<ImageButton
+				android:id="@+id/toggle_password"
+				android:layout_width="wrap_content"
+				android:layout_height="wrap_content"
+				android:src="@drawable/ic_menu_view" />
 		</LinearLayout>
 		<LinearLayout
-        android:id="@+id/otpEntry"
+			android:id="@+id/keyfileLine"
-        android:layout_width="fill_parent"
+			android:layout_width="fill_parent"
-        android:layout_height="wrap_content"
+			android:layout_height="wrap_content"
-		android:visibility="gone"
+			android:orientation="horizontal">
-		android:orientation="vertical"
+			<EditText
+				android:id="@+id/pass_keyfile"
+				android:layout_width="0px"
+				android:layout_height="wrap_content"
+				android:singleLine="true"
+				android:layout_weight="1"
+				android:hint="@string/entry_keyfile" />
+			<ImageButton
+				android:id="@+id/browse_button"
+				android:layout_width="wrap_content"
+				android:layout_height="wrap_content"
+				android:src="@drawable/ic_launcher_folder_small" />
+		</LinearLayout>
+		<LinearLayout
+			android:id="@+id/otpView"
+			android:layout_marginLeft="12dip"
+			android:layout_marginRight="12dip"
+			android:layout_width="fill_parent"
+			android:layout_height="wrap_content"
+			android:orientation="vertical"
 		>
-			<TextView
+			<LinearLayout
-        android:id="@+id/otp_expl"
+			android:id="@+id/otpInitView"
-        android:layout_width="wrap_content"
+			android:layout_width="fill_parent"
-        android:layout_height="wrap_content"
+			android:layout_height="wrap_content"
-        android:text="@string/otp_explanation" />
+			android:orientation="vertical"
+		>
+				<Button
+				android:id="@+id/init_otp"
+				android:text="@string/init_otp"
+				android:layout_width="wrap_content"
+				android:layout_height="wrap_content"/>
+				<TextView
+					android:id="@+id/otps_pending"
+				android:text="@string/otps_pending"
+				android:layout_width="wrap_content"
+				android:layout_height="wrap_content" />
+			</LinearLayout>
+			<LinearLayout
+			android:id="@+id/otpEntry"
+			android:layout_width="fill_parent"
+			android:layout_height="wrap_content"
+			android:visibility="gone"
+			android:orientation="vertical"
+		>
+				<TextView
+			android:id="@+id/otp_expl"
+			android:layout_width="wrap_content"
+			android:layout_height="wrap_content"
+			android:text="@string/otp_explanation" />
 
-			<EditText
+				<EditText
-						android:id="@+id/otp1"
+							android:id="@+id/otp1"
-						android:layout_width="fill_parent"
+							android:layout_width="fill_parent"
-						android:layout_height="wrap_content"
+							android:layout_height="wrap_content"
-						android:text="93317749"
+							android:text="93317749"
-						android:singleLine="true" />
+							android:singleLine="true" />
-			<EditText
+				<EditText
-						android:id="@+id/otp2"
+							android:id="@+id/otp2"
-						android:text="54719327"
+							android:text="54719327"
-						android:layout_width="fill_parent"
+							android:layout_width="fill_parent"
-						android:layout_height="wrap_content"
+							android:layout_height="wrap_content"
-						android:singleLine="true" />
+							android:singleLine="true" />
-			<EditText
+				<EditText
-						android:id="@+id/otp3"
+							android:id="@+id/otp3"
-						android:text="49844651"
+							android:text="49844651"
-						android:layout_width="fill_parent"
+							android:layout_width="fill_parent"
-						android:layout_height="wrap_content"
+							android:layout_height="wrap_content"
-						android:singleLine="true" />
+							android:singleLine="true" />
-			<EditText
+				<EditText
-						android:id="@+id/otp4"
+							android:id="@+id/otp4"
-						android:layout_width="fill_parent"
+							android:layout_width="fill_parent"
-						android:layout_height="wrap_content"
+							android:layout_height="wrap_content"
-						android:singleLine="true" />
+							android:singleLine="true" />
-			<EditText
+				<EditText
-						android:id="@+id/otp5"
+							android:id="@+id/otp5"
-						android:layout_width="fill_parent"
+							android:layout_width="fill_parent"
-						android:layout_height="wrap_content"
+							android:layout_height="wrap_content"
-						android:singleLine="true" />
+							android:singleLine="true" />
-			<EditText
+				<EditText
-						android:id="@+id/otp6"
+							android:id="@+id/otp6"
-						android:layout_width="fill_parent"
+							android:layout_width="fill_parent"
-						android:layout_height="wrap_content"
+							android:layout_height="wrap_content"
-						android:singleLine="true" />
+							android:singleLine="true" />
+
+			</LinearLayout>
 
 		</LinearLayout>
-		
+		<LinearLayout
+			android:id="@+id/otpSecretLine"
+			android:layout_width="fill_parent"
+			android:layout_height="wrap_content"
+			android:orientation="horizontal">
+			<EditText
+				android:id="@+id/pass_otpsecret"
+				android:layout_width="0px"
+				android:layout_height="wrap_content"
+				android:singleLine="true"
+				android:layout_weight="1"
+				android:hint="@string/otpsecret_hint" />
+			<Spinner
+		android:id="@+id/otpsecret_format_spinner"
+		android:layout_width="wrap_content"
+		android:layout_height="wrap_content"
+		/>
+		</LinearLayout>
+		<Button
+			android:id="@+id/pass_ok"
+			android:text="@android:string/ok"
+			android:layout_width="fill_parent"
+			android:layout_height="wrap_content"/>
+		<Button
+			android:id="@+id/kill_app"
+			android:text="@string/kill_app_label"
+			android:layout_width="fill_parent"
+			android:layout_height="wrap_content" />
+		<CheckBox
+			android:id="@+id/enable_quickunlock"
+			android:layout_width="wrap_content"
+			android:layout_height="wrap_content"
+			android:text="@string/enable_quickunlock" />
 	</LinearLayout>
-	<Button
+</ScrollView>
-        android:id="@+id/pass_ok"
-        android:text="@android:string/ok"
-        android:layout_width="fill_parent"
-        android:layout_height="wrap_content"/>
-	<Button
-        android:id="@+id/kill_app"
-        android:text="@string/kill_app_label"
-        android:layout_width="fill_parent"
-        android:layout_height="wrap_content" />
-    <CheckBox
-        android:id="@+id/enable_quickunlock"
-        android:layout_width="wrap_content"
-        android:layout_height="wrap_content"
-        android:text="@string/enable_quickunlock" />
-</LinearLayout>

src/keepass2android/Resources/values/strings.xml

@@ -143,6 +143,7 @@
   <string name="omitbackup_summary">Omit \'Backup\' and Recycle Bin group from search results</string>
   <string name="pass_filename">KeePass database filename</string>
   <string name="password_title">Enter database password</string>
+  <string name="master_key_type">Select master key type:</string>
   <string name="progress_create">Creating new database…</string>
   <string name="create_database">Create database</string>
   <string name="progress_title">Working…</string>
@@ -299,9 +300,17 @@
 	<string name="UpdatedRemoteFileOnLoad">Updated remote file.</string>
 	<string name="NotifyOpenFromLocalDueToConflict">Opened local file due to conflict with changes in remote file. Use Synchronize menu to merge.</string>
 	<string name="LoadedFromRemoteInSync">Remote file and cache are synchronized.</string>
-	<string name="UpdatedCachedFileOnLoad">Updated local cache copy of database.</string>
+	<string name="UpdatedCachedFileOnLoad">Updated local cache copy of %1$s.</string>
 	<string name="RemoteDatabaseUnchanged">No changes detected.</string>
 
+	<string name="ResolvedCacheConflictByUsingRemoteOtpAux">Updated cached OTP auxiliary file: Remote counter was higher.</string>
+	<string name="ResolvedCacheConflictByUsingLocalOtpAux">Updated remote OTP auxiliary file: Local counter was higher.</string>
+
+	<string name="SynchronizingOtpAuxFile">Synchronizing OTP auxiliary file…</string>
+	
+	<string name="database_file">database file</string>
+	<string name="otp_aux_file">OTP auxiliary file</string>
+
 	<string name="ErrorOcurred">An error occured:</string>
 
 	<string name="synchronize_database_menu">Synchronize database…</string>
@@ -343,14 +352,19 @@
 
 	<string name="error_adding_keyfile">Error while adding the keyfile!</string>
 
-	<string name="init_otp">Enter OTPs…</string>
+	<string name="init_otp">Load OTP auxiliary file…</string>
 	<string name="otp_explanation">Enter the next One-time-passwords (OTPs). Swipe your Yubikey NEO at the back of your device to enter via NFC.</string>
 	<string name="otp_hint">OTP %1$d</string>
 	<string name="CouldntLoadOtpAuxFile">Could not load auxiliary OTP file!</string>
 	<string name="otp_discarded_because_no_db">Please select database first. OTP is discarded for security reasons.</string>
 	<string name="otp_discarded_no_space">OTP discarded: All OTPs already entered!</string>
+	<string name="otp_discarded_because_db_open">Please close database first. OTP is discarded.</string>
 	<string name="otps_pending">(One or more OTPs already available)</string>
-
+	<string name="otpsecret_hint">OTP secret (e.g. 01 23 ab cd…)</string>
+	<string name="CouldntParseOtpSecret">Error parsing OTP secret!</string>
+	<string name="OtpKeyError">Failed to create OTP key! Make sure you have entered the correct OTPs.</string>
+	<string name="ErrorUpdatingOtpAuxFile">Error updating OTP auxiliary file!</string>
+	<string name="SavingOtpAuxFile">Saving auxiliary OTP file…</string>
 
 	<string name="loading">Loading…</string>
 	
@@ -477,5 +491,6 @@ Initial public release
 		<item>Password only</item>
 		<item>Password + Key file</item>
 		<item>Password + OTP</item>
+		<item>Password + OTP secret (recovery mode)</item>
 	</string-array>
 </resources>

src/keepass2android/addons/OtpKeyProv/OathHotpKeyProv.cs

@@ -49,13 +49,19 @@ namespace OtpKeyProv
 		private static IOConnectionInfo GetAuxFileIoc(KeyProviderQueryContext ctx)
 		{
 			IOConnectionInfo ioc = ctx.DatabaseIOInfo.CloneDeep();
-			IFileStorage fileStorage = App.Kp2a.GetOtpAuxFileStorage(ioc);
+			var iocAux = GetAuxFileIoc(ioc);
-			IOConnectionInfo iocAux = fileStorage.GetFilePath(fileStorage.GetParentPath(ioc),
-			                                                  fileStorage.GetFilenameWithoutPathAndExt(ioc) + AuxFileExt);
 
 			return iocAux;
 		}
 
+		public static IOConnectionInfo GetAuxFileIoc(IOConnectionInfo databaseIoc)
+		{
+			IFileStorage fileStorage = App.Kp2a.GetOtpAuxFileStorage(databaseIoc);
+			IOConnectionInfo iocAux = fileStorage.GetFilePath(fileStorage.GetParentPath(databaseIoc),
+			                                                  fileStorage.GetFilenameWithoutPathAndExt(databaseIoc) + AuxFileExt);
+			return iocAux;
+		}
+
 		public static OtpInfo LoadOtpInfo(KeyProviderQueryContext ctx)
 		{
 			return OtpInfo.Load(GetAuxFileIoc(ctx));
@@ -130,7 +136,7 @@ namespace OtpKeyProv
 		}
 
 
-		private static bool CreateAuxFile(OtpInfo otpInfo,
+		public static bool CreateAuxFile(OtpInfo otpInfo,
 			KeyProviderQueryContext ctx)
 		{
 			otpInfo.Type = ProvType;

src/keepass2android/addons/OtpKeyProv/OtpAuxCachingFileStorage.cs

@@ -0,0 +1,70 @@
+using System.IO;
+using System.Xml.Serialization;
+using KeePassLib.Serialization;
+using OtpKeyProv;
+using keepass2android.Io;
+
+namespace keepass2android.addons.OtpKeyProv
+{
+	/// <summary>
+	/// Class which provides caching for OtpInfo-files. This is an extension to CachingFileStorage required to handle conflicts directly when loading.
+	/// </summary>
+	class OtpAuxCachingFileStorage: CachingFileStorage
+	{
+		private readonly IOtpAuxCacheSupervisor _cacheSupervisor;
+
+		internal interface IOtpAuxCacheSupervisor: ICacheSupervisor
+		{
+			/// <summary>
+			/// called when there was a conflict which was resolved by using the remote file.
+			/// </summary>
+			void ResolvedCacheConflictByUsingRemote(IOConnectionInfo ioc);
+
+			/// <summary>
+			/// called when there was a conflict which was resolved by using the local file.
+			/// </summary>
+			void ResolvedCacheConflictByUsingLocal(IOConnectionInfo ioc);
+		}
+
+
+		public OtpAuxCachingFileStorage(IFileStorage cachedStorage, string cacheDir, IOtpAuxCacheSupervisor cacheSupervisor)
+			: base(cachedStorage, cacheDir, cacheSupervisor)
+		{
+			_cacheSupervisor = cacheSupervisor;
+		}
+
+		protected override Stream OpenFileForReadWithConflict(IOConnectionInfo ioc, string cachedFilePath)
+		{
+			OtpInfo remoteOtpInfo, localOtpInfo;
+			//load both files
+			XmlSerializer xs = new XmlSerializer(typeof (OtpInfo));
+			localOtpInfo = (OtpInfo) xs.Deserialize(File.OpenRead(cachedFilePath));
+			using (Stream remoteStream = _cachedStorage.OpenFileForRead(ioc))
+			{
+				remoteOtpInfo = (OtpInfo) xs.Deserialize(remoteStream);
+			}
+
+			//see which OtpInfo has the bigger Counter value and use this one:
+			if (localOtpInfo.Counter > remoteOtpInfo.Counter)
+			{
+				//overwrite the remote file
+				UpdateRemoteFile(File.OpenRead(cachedFilePath), 
+				                 ioc, 
+				                 App.Kp2a.GetBooleanPreference(PreferenceKey.UseFileTransactions),
+				                 GetBaseVersionHash(ioc)
+					);
+
+				_cacheSupervisor.ResolvedCacheConflictByUsingRemote(ioc);
+			}
+			else
+			{
+				//overwrite the local file:
+				UpdateCacheFromRemote(ioc, cachedFilePath);
+				_cacheSupervisor.ResolvedCacheConflictByUsingLocal(ioc);
+			}
+
+			//now return the local file in any way:
+			return File.OpenRead(cachedFilePath);
+		}
+	}
+}

src/keepass2android/addons/OtpKeyProv/OtpInfo.cs

@@ -197,18 +197,8 @@ namespace OtpKeyProv
 				using (var trans = App.Kp2a.GetOtpAuxFileStorage(ioc)
 					               .OpenWriteTransaction(ioc, App.Kp2a.GetBooleanPreference(PreferenceKey.UseFileTransactions)))
 				{
-					XmlWriterSettings xws = new XmlWriterSettings();
+					var stream = trans.OpenFile();
-					xws.CloseOutput = true;
+					WriteToStream(otpInfo, stream);
-					xws.Encoding = StrUtil.Utf8;
-					xws.Indent = true;
-					xws.IndentChars = "\t";
-
-					XmlWriter xw = XmlWriter.Create(trans.OpenFile(), xws);
-
-					XmlSerializer xs = new XmlSerializer(typeof (OtpInfo));
-					xs.Serialize(xw, otpInfo);
-
-					xw.Close();
 					trans.CommitWrite();
 				}
 				return true;
@@ -222,6 +212,31 @@ namespace OtpKeyProv
 			return false;
 		}
 
+
+		public static void WriteToStream(OtpInfo otpInfo, Stream stream)
+		{
+			var xws = XmlWriterSettings();
+
+			XmlWriter xw = XmlWriter.Create(stream, xws);
+
+			XmlSerializer xs = new XmlSerializer(typeof (OtpInfo));
+			xs.Serialize(xw, otpInfo);
+
+			xw.Close();
+		}
+
+		public static XmlWriterSettings XmlWriterSettings()
+		{
+			XmlWriterSettings xws = new XmlWriterSettings
+				{
+					CloseOutput = true,
+					Encoding = StrUtil.Utf8,
+					Indent = true,
+					IndentChars = "\t"
+				};
+			return xws;
+		}
+
 		public void EncryptSecret()
 		{
 			if(m_pbSecret == null) throw new InvalidOperationException();

src/keepass2android/app/App.cs

@@ -32,6 +32,7 @@ using Android.Preferences;
 using TwofishCipher;
 #endif
 using keepass2android.Io;
+using keepass2android.addons.OtpKeyProv;
 
 namespace keepass2android
 {
@@ -294,8 +295,11 @@ namespace keepass2android
 
 					builder.SetNegativeButton(GetResourceString(noString), noHandler);
 
-					builder.SetNeutralButton(ctx.GetString(Android.Resource.String.Cancel),
+					if (cancelHandler != null)
-											 cancelHandler);
+					{
+						builder.SetNeutralButton(ctx.GetString(Android.Resource.String.Cancel),
+												 cancelHandler);	
+					}
 
 					Dialog dialog = builder.Create();
 					dialog.Show();
@@ -447,7 +451,7 @@ namespace keepass2android
             return _db;
         }
 
-		void ShowToast(string message)
+		internal void ShowToast(string message)
 		{
 			var handler = new Handler(Looper.MainLooper);
 			handler.Post(() => { Toast.MakeText(Application.Context, message, ToastLength.Long).Show(); });
@@ -466,7 +470,8 @@ namespace keepass2android
 
 		public void UpdatedCachedFileOnLoad(IOConnectionInfo ioc)
 		{
-			ShowToast(Application.Context.GetString(Resource.String.UpdatedCachedFileOnLoad));
+			ShowToast(Application.Context.GetString(Resource.String.UpdatedCachedFileOnLoad, 
+				new Java.Lang.Object[] { Application.Context.GetString(Resource.String.database_file) }));
 		}
 
 		public void UpdatedRemoteFileOnLoad(IOConnectionInfo ioc)
@@ -510,7 +515,7 @@ namespace keepass2android
 				
 				if (DatabaseCacheEnabled)
 				{
-					return new CachingFileStorage(innerFileStorage, Application.Context.CacheDir.Path, this);
+					return new OtpAuxCachingFileStorage(innerFileStorage, Application.Context.CacheDir.Path, new OtpAuxCacheSupervisor(this));
 				}
 				else
 				{
@@ -532,7 +537,7 @@ namespace keepass2android
 	}
 
 
-    ///Application class for Keepass2Android: Contains static Database variable to be used by all components.
+	///Application class for Keepass2Android: Contains static Database variable to be used by all components.
 #if NoNet
 	[Application(Debuggable=false, Label=AppNames.AppName)]
 #else

src/keepass2android/app/OtpAuxCacheSupervisor.cs

@@ -0,0 +1,59 @@
+using System;
+using Android.App;
+using KeePassLib.Serialization;
+using keepass2android.addons.OtpKeyProv;
+
+namespace keepass2android
+{
+	public class OtpAuxCacheSupervisor : OtpAuxCachingFileStorage.IOtpAuxCacheSupervisor
+	{
+		private readonly Kp2aApp _app;
+
+		public OtpAuxCacheSupervisor(Kp2aApp app)
+		{
+			_app = app;
+		}
+
+		public void CouldntSaveToRemote(IOConnectionInfo ioc, Exception ex)
+		{
+			_app.CouldntSaveToRemote(ioc, ex);
+		}
+
+		public void CouldntOpenFromRemote(IOConnectionInfo ioc, Exception ex)
+		{
+			_app.CouldntOpenFromRemote(ioc, ex);
+		}
+
+		public void UpdatedCachedFileOnLoad(IOConnectionInfo ioc)
+		{
+			_app.ShowToast(Application.Context.GetString(Resource.String.UpdatedCachedFileOnLoad,
+			                                             new Java.Lang.Object[] { Application.Context.GetString(Resource.String.otp_aux_file) }));
+		}
+
+		public void UpdatedRemoteFileOnLoad(IOConnectionInfo ioc)
+		{
+			_app.UpdatedRemoteFileOnLoad(ioc);
+		}
+
+		public void NotifyOpenFromLocalDueToConflict(IOConnectionInfo ioc)
+		{
+			//must not be called . Conflicts should be resolved.
+			throw new InvalidOperationException();
+		}
+
+		public void LoadedFromRemoteInSync(IOConnectionInfo ioc)
+		{
+			_app.LoadedFromRemoteInSync(ioc);
+		}
+
+		public void ResolvedCacheConflictByUsingRemote(IOConnectionInfo ioc)
+		{
+			_app.ShowToast(Application.Context.GetString(Resource.String.ResolvedCacheConflictByUsingRemoteOtpAux));
+		}
+
+		public void ResolvedCacheConflictByUsingLocal(IOConnectionInfo ioc)
+		{
+			_app.ShowToast(Application.Context.GetString(Resource.String.ResolvedCacheConflictByUsingLocalOtpAux));
+		}
+	}
+}

src/keepass2android/fileselect/FileSelectActivity.cs

@@ -373,7 +373,7 @@ namespace keepass2android
 #if !EXCLUDE_FILECHOOSER
 				StartFileChooser(ioc.Path);
 #else
-				LaunchPasswordActivityForIoc(new IOConnectionInfo { Path = "/mnt/sdcard/keepass/yubi2.kdbx"});
+				LaunchPasswordActivityForIoc(new IOConnectionInfo { Path = "/mnt/sdcard/keepass/yubi.kdbx"});
 #endif
 			}
 			if ((resultCode == Result.Canceled) && (data != null) && (data.HasExtra("EXTRA_ERROR_MESSAGE")))

src/keepass2android/keepass2android.csproj

@@ -84,9 +84,11 @@
   <ItemGroup>
     <Compile Include="addons\OtpKeyProv\EncodingUtil.cs" />
     <Compile Include="addons\OtpKeyProv\OathHotpKeyProv.cs" />
+    <Compile Include="addons\OtpKeyProv\OtpAuxCachingFileStorage.cs" />
     <Compile Include="addons\OtpKeyProv\OtpInfo.cs" />
     <Compile Include="addons\OtpKeyProv\OtpUtil.cs" />
     <Compile Include="app\NoFileStorageFoundException.cs" />
+    <Compile Include="app\OtpAuxCacheSupervisor.cs" />
     <Compile Include="CreateDatabaseActivity.cs" />
     <Compile Include="fileselect\FileChooserFileProvider.cs" />
     <Compile Include="fileselect\FileStorageSetupActivity.cs" />