Improved Certificate Handling (fixed problem with Certificate validation)

src/KeePassLib2Android/KeePassLib2Android.csproj

@@ -20,7 +20,7 @@
     <DebugType>full</DebugType>
     <Optimize>False</Optimize>
     <OutputPath>bin\Debug</OutputPath>
-    <DefineConstants>DEBUG;EXCLUDE_TWOFISH;EXCLUDE_KEYBOARD;EXCLUDE_KEYTRANSFORM;INCLUDE_FILECHOOSER;INCLUDE_JAVAFILESTORAGE</DefineConstants>
+    <DefineConstants>DEBUG;EXCLUDE_TWOFISH;EXCLUDE_KEYBOARD;EXCLUDE_KEYTRANSFORM;EXCLUDE_FILECHOOSER;EXCLUDE_JAVAFILESTORAGE</DefineConstants>
     <ErrorReport>prompt</ErrorReport>
     <WarningLevel>4</WarningLevel>
     <ConsolePause>False</ConsolePause>

src/KeePassLib2Android/Serialization/IOConnection.cs

@@ -317,7 +317,7 @@ namespace KeePassLib.Serialization
 				if ((ex.Response is HttpWebResponse) && (((HttpWebResponse)ex.Response).StatusCode == HttpStatusCode.Unauthorized))
 					return CreateWebClient(ioc, true).OpenRead(new Uri(ioc.Path));
 				else
-					throw ex;
+					throw;
 			}
 
 		}
@@ -369,7 +369,7 @@ namespace KeePassLib.Serialization
 					if ((ex.Response is HttpWebResponse) && (((HttpWebResponse) ex.Response).StatusCode == HttpStatusCode.Unauthorized))
 						uploadData(IOConnection.CreateWebClient(ioc, true));
 					else
-						throw ex;
+						throw;
 				}
 				
 			}

src/Kp2aBusinessLogic/IKp2aApp.cs

@@ -78,5 +78,11 @@ namespace keepass2android
 		IFileStorage GetFileStorage(IOConnectionInfo iocInfo);
 
 		void TriggerReload(Context context);
+
+		/// <summary>
+		/// Handles a failed certificate validation. Returns true if the users wants to continue, false otherwise.
+		/// see http://msdn.microsoft.com/en-us/library/system.net.icertificatepolicy(v=vs.110).aspx
+		/// </summary>
+		bool OnServerCertificateError(int certificateProblem);
     }
 }

src/Kp2aBusinessLogic/Io/BuiltInFileStorage.cs

@@ -3,8 +3,10 @@ using System.Collections.Generic;
 using System.Globalization;
 using System.IO;
 using System.Net;
+using System.Net.Security;
 using Android.Content;
 using Android.OS;
+using Java.Security.Cert;
 using KeePassLib.Serialization;
 using KeePassLib.Utility;
 
@@ -12,6 +14,56 @@ namespace keepass2android.Io
 {
 	public class BuiltInFileStorage: IFileStorage
 	{
+		public enum CertificateProblem :long
+		{
+			CertEXPIRED = 0x800B0101,
+			CertVALIDITYPERIODNESTING = 0x800B0102,
+			CertROLE = 0x800B0103,
+			CertPATHLENCONST = 0x800B0104,
+			CertCRITICAL = 0x800B0105,
+			CertPURPOSE = 0x800B0106,
+			CertISSUERCHAINING = 0x800B0107,
+			CertMALFORMED = 0x800B0108,
+			CertUNTRUSTEDROOT = 0x800B0109,
+			CertCHAINING = 0x800B010A,
+			CertREVOKED = 0x800B010C,
+			CertUNTRUSTEDTESTROOT = 0x800B010D,
+			CertREVOCATION_FAILURE = 0x800B010E,
+			CertCN_NO_MATCH = 0x800B010F,
+			CertWRONG_USAGE = 0x800B0110,
+			CertUNTRUSTEDCA = 0x800B0112
+		}
+
+
+		private readonly IKp2aApp _app;
+
+		class CertificatePolicity: ICertificatePolicy 
+		{
+			private readonly IKp2aApp _app;
+
+			public CertificatePolicity(IKp2aApp app)
+			{
+				_app = app;
+			}
+
+			public bool CheckValidationResult(ServicePoint srvPoint, System.Security.Cryptography.X509Certificates.X509Certificate certificate, WebRequest request,
+			                                  int certificateProblem)
+			{
+				if (certificateProblem == 0) //ok
+					return true;
+				return _app.OnServerCertificateError(certificateProblem);
+			}
+		}
+
+
+		public BuiltInFileStorage(IKp2aApp app)
+		{
+			_app = app;
+			//use the obsolute CertificatePolicy because the ServerCertificateValidationCallback isn't called in Mono for Android (?)
+			ServicePointManager.CertificatePolicy = new CertificatePolicity(app);
+			
+		}
+
 		public IEnumerable<string> SupportedProtocols 
 		{ 
 			get 
@@ -68,26 +120,51 @@ namespace keepass2android.Io
 			}
 			catch (WebException ex)
 			{
-				if ((ex.Response is HttpWebResponse) && (((HttpWebResponse)ex.Response).StatusCode == HttpStatusCode.NotFound))
-				{
-					throw new FileNotFoundException(ex.Message, ioc.Path, ex);
-				}
+				ConvertException(ioc, ex);
 				throw;
 			}
+		}
 
+		private void ConvertException(IOConnectionInfo ioc, WebException ex)
+		{
+			if ((ex.Response is HttpWebResponse) && (((HttpWebResponse) ex.Response).StatusCode == HttpStatusCode.NotFound))
+			{
+				throw new FileNotFoundException(ex.Message, ioc.Path, ex);
+			}
+			if (ex.Status == WebExceptionStatus.TrustFailure)
+			{
+				throw new Exception(_app.GetResourceString(UiStringKey.CertificateFailure), ex);
+			}
+			var inner1 = ex.InnerException as IOException;
+			if (inner1 != null)
+			{
+				var inner2 = inner1.InnerException;
+				if (inner2 != null)
+				{
+					if (inner2.Message.Contains("Invalid certificate received from server."))
+					{
+						throw new Exception(_app.GetResourceString(UiStringKey.CertificateFailure), ex);
+					}
+				}
+				 
+			}
 		}
 
 		public IWriteTransaction OpenWriteTransaction(IOConnectionInfo ioc, bool useFileTransaction)
 		{
-			return new BuiltInFileTransaction(ioc, useFileTransaction);
+			return new BuiltInFileTransaction(ioc, useFileTransaction, this);
 		}
 
 		public class BuiltInFileTransaction : IWriteTransaction
 		{
+			private readonly IOConnectionInfo _ioc;
+			private readonly BuiltInFileStorage _fileStorage;
 			private readonly FileTransactionEx _transaction;
 
-			public BuiltInFileTransaction(IOConnectionInfo ioc, bool useFileTransaction)
+			public BuiltInFileTransaction(IOConnectionInfo ioc, bool useFileTransaction, BuiltInFileStorage fileStorage)
 			{
+				_ioc = ioc;
+				_fileStorage = fileStorage;
 				_transaction = new FileTransactionEx(ioc, useFileTransaction);
 			}
 
@@ -98,12 +175,30 @@ namespace keepass2android.Io
 
 			public Stream OpenFile()
 			{
-				return _transaction.OpenWrite();
+				try
+				{
+					return _transaction.OpenWrite();
+				}
+				catch (WebException ex)
+				{
+					_fileStorage.ConvertException(_ioc, ex);
+					throw;
+				}
+				
 			}
 
 			public void CommitWrite()
 			{
-				_transaction.CommitWrite();
+				try
+				{
+					_transaction.CommitWrite();
+				}
+				catch (WebException ex)
+				{
+					_fileStorage.ConvertException(_ioc, ex);
+					throw;
+				}
+				
 			}
 		}
 

src/Kp2aBusinessLogic/Kp2aBusinessLogic.csproj

@@ -20,7 +20,7 @@
     <DebugType>full</DebugType>
     <Optimize>false</Optimize>
     <OutputPath>bin\Debug\</OutputPath>
-    <DefineConstants>TRACE;DEBUG;EXCLUDE_TWOFISH;EXCLUDE_KEYBOARD;EXCLUDE_KEYTRANSFORM;INCLUDE_FILECHOOSER;INCLUDE_JAVAFILESTORAGE</DefineConstants>
+    <DefineConstants>TRACE;DEBUG;EXCLUDE_TWOFISH;EXCLUDE_KEYBOARD;EXCLUDE_KEYTRANSFORM;EXCLUDE_FILECHOOSER;EXCLUDE_JAVAFILESTORAGE</DefineConstants>
     <ErrorReport>prompt</ErrorReport>
     <WarningLevel>4</WarningLevel>
   </PropertyGroup>
@@ -44,6 +44,7 @@
   </PropertyGroup>
   <ItemGroup>
     <Reference Include="Mono.Android" />
+    <Reference Include="Mono.Security" />
     <Reference Include="mscorlib" />
     <Reference Include="System" />
     <Reference Include="System.Core" />

src/Kp2aBusinessLogic/UiStringKey.cs

@@ -46,6 +46,7 @@ namespace keepass2android
 		CannotMoveGroupHere,
 		ErrorOcurred,
 		SynchronizingOtpAuxFile,
-		SavingOtpAuxFile
+		SavingOtpAuxFile,
+		CertificateFailure
     }
 }

src/Kp2aUnitTests/MainActivity.cs

@@ -18,9 +18,9 @@ namespace Kp2aUnitTests
         {
             TestRunner runner = new TestRunner();
             // Run all tests from this assembly
-            runner.AddTests(Assembly.GetExecutingAssembly());
-			//runner.AddTests(new List<Type> { typeof(TestSynchronizeCachedDatabase) });
-			//runner.AddTests(typeof(TestSaveDbCached).GetMethod("TestLoadEditSaveWhenModified"));
+            //runner.AddTests(Assembly.GetExecutingAssembly());
+			//runner.AddTests(new List<Type> { typeof(TestSynchronizeCachedDatabase)});
+			runner.AddTests(typeof(TestLoadDb).GetMethod("LoadErrorWithCertificateTrustFailure"));
 			
 			//runner.AddTests(new List<Type> { typeof(TestSaveDb) });
 			//runner.AddTests(new List<Type> { typeof(TestCachingFileStorage) });

src/Kp2aUnitTests/Resources/Resource.Designer.cs

@@ -2,7 +2,7 @@
 //------------------------------------------------------------------------------
 // <auto-generated>
 //     Dieser Code wurde von einem Tool generiert.
-//     Laufzeitversion:4.0.30319.18051
+//     Laufzeitversion:4.0.30319.34003
 //
 //     Änderungen an dieser Datei können falsches Verhalten verursachen und gehen verloren, wenn
 //     der Code erneut generiert wird.

src/Kp2aUnitTests/TestBase.cs

@@ -66,7 +66,7 @@ namespace Kp2aUnitTests
 			var app = CreateTestKp2aApp();
 			app.CreateNewDatabase();
 			bool loadSuccesful = false;
-			LoadDb task = new LoadDb(app, new IOConnectionInfo() { Path = filename }, null, password, keyfile, new ActionOnFinish((success, message) =>
+			LoadDb task = new LoadDb(app, new IOConnectionInfo() { Path = filename }, null, CreateKey(password, keyfile), keyfile, new ActionOnFinish((success, message) =>
 				{
 					if (!success)
 						Kp2aLog.Log(message);
@@ -80,7 +80,20 @@ namespace Kp2aUnitTests
 			Assert.IsTrue(loadSuccesful);
 			return app;
 		}
-
+		protected static CompositeKey CreateKey(string password, string keyfile)
+		{
+			CompositeKey key = new CompositeKey();
+			key.AddUserKey(new KcpPassword(password));
+			if (!String.IsNullOrEmpty(keyfile))
+				key.AddUserKey(new KcpKeyFile(keyfile));
+			return key;
+		}
+		protected static CompositeKey CreateKey(string password)
+		{
+			CompositeKey key = new CompositeKey();
+			key.AddUserKey(new KcpPassword(password));
+			return key;
+		}
 		protected virtual TestKp2aApp CreateTestKp2aApp()
 		{
 			TestKp2aApp app = new TestKp2aApp();

src/Kp2aUnitTests/TestCachingFileStorage.cs

@@ -14,6 +14,12 @@ namespace Kp2aUnitTests
 	[TestClass]
 	class TestCachingFileStorage: TestBase
 	{
+		[TestInitialize]
+		public void InitTests()
+		{
+			TestFileStorage.Offline = false;
+		}
+
 		private TestFileStorage _testFileStorage;
 		private CachingFileStorage _fileStorage;
 		private static readonly string CachingTestFile = DefaultDirectory + "cachingTestFile.txt";
@@ -37,7 +43,7 @@ namespace Kp2aUnitTests
 			Assert.AreEqual(MemoryStreamToString(fileContents), _defaultCacheFileContents);
 
 			//let the base file storage go offline:
-			_testFileStorage.Offline = true;
+			TestFileStorage.Offline = true;
 
 			//now try to read the file again:
 			MemoryStream fileContents2 = ReadToMemoryStream(_fileStorage, CachingTestFile);
@@ -98,7 +104,7 @@ namespace Kp2aUnitTests
 			_testCacheSupervisor.AssertSingleCall(TestCacheSupervisor.UpdatedCachedFileOnLoadId);
 
 			//let the base file storage go offline:
-			_testFileStorage.Offline = true;
+			TestFileStorage.Offline = true;
 
 			//write something to the cache:
 			string newContent = "new content";
@@ -116,7 +122,7 @@ namespace Kp2aUnitTests
 			Assert.AreEqual(MemoryStreamToString(fileContents2), newContent);
 
 			//now go online and read again. This should trigger a sync and the modified data must be returned
-			_testFileStorage.Offline = false;
+			TestFileStorage.Offline = false;
 			MemoryStream fileContents3 = ReadToMemoryStream(_fileStorage, CachingTestFile);
 			Assert.AreEqual(MemoryStreamToString(fileContents3), newContent);
 
@@ -141,7 +147,7 @@ namespace Kp2aUnitTests
 			_testCacheSupervisor.AssertSingleCall(TestCacheSupervisor.UpdatedCachedFileOnLoadId);
 
 			//let the base file storage go offline:
-			_testFileStorage.Offline = true;
+			TestFileStorage.Offline = true;
 
 			//write something to the cache:
 			string newLocalContent = "new local content";
@@ -153,7 +159,7 @@ namespace Kp2aUnitTests
 			File.WriteAllText(CachingTestFile, "new remote content");
 
 			//go online again:
-			_testFileStorage.Offline = false;
+			TestFileStorage.Offline = false;
 
 			//now try to read the file again:
 			MemoryStream fileContents2 = ReadToMemoryStream(_fileStorage, CachingTestFile);
@@ -231,7 +237,7 @@ namespace Kp2aUnitTests
 
 		private void SetupFileStorage()
 		{
-			_testFileStorage = new TestFileStorage();
+			_testFileStorage = new TestFileStorage(new TestKp2aApp());
 			_testCacheSupervisor = new TestCacheSupervisor();
 			//_fileStorage = new CachingFileStorage(_testFileStorage, Application.Context.CacheDir.Path, _testCacheSupervisor);
 			_fileStorage = new CachingFileStorage(_testFileStorage, "/mnt/sdcard/kp2atest_cache", _testCacheSupervisor);

src/Kp2aUnitTests/TestFileStorage.cs

@@ -1,16 +1,23 @@
 using System;
 using System.Collections.Generic;
 using System.IO;
+using Android.Content;
+using Android.OS;
 using KeePassLib.Serialization;
+using keepass2android;
 using keepass2android.Io;
 
 namespace Kp2aUnitTests
 {
 	internal class TestFileStorage: IFileStorage
 	{
-		private BuiltInFileStorage _builtIn = new BuiltInFileStorage();
+		public TestFileStorage(IKp2aApp app)
+		{
+			_builtIn = new BuiltInFileStorage(app);
+		}
+		private BuiltInFileStorage _builtIn;
 
-		public bool Offline { get; set; }
+		public static bool Offline { get; set; }
 
 		public IEnumerable<string> SupportedProtocols { get { yield return "test"; } }
 
@@ -96,6 +103,11 @@ namespace Kp2aUnitTests
 			return _builtIn.RequiresCredentials(ioc);
 		}
 
+		public void CreateDirectory(IOConnectionInfo ioc, string newDirName)
+		{
+			throw new NotImplementedException();
+		}
+
 		public void CreateDirectory(IOConnectionInfo ioc)
 		{
 			throw new NotImplementedException();
@@ -110,5 +122,66 @@ namespace Kp2aUnitTests
 		{
 			throw new NotImplementedException();
 		}
+
+		public bool RequiresSetup(IOConnectionInfo ioConnection)
+		{
+			return false;
+		}
+
+		public string IocToPath(IOConnectionInfo ioc)
+		{
+			return ioc.Path;
+		}
+
+		public void StartSelectFile(IFileStorageSetupInitiatorActivity activity, bool isForSave, int requestCode, string protocolId)
+		{
+			throw new NotImplementedException();
+		}
+
+		public void PrepareFileUsage(IFileStorageSetupInitiatorActivity activity, IOConnectionInfo ioc, int requestCode,
+		                             bool alwaysReturnSuccess)
+		{
+			throw new NotImplementedException();
+		}
+
+		public void OnCreate(IFileStorageSetupActivity activity, Bundle savedInstanceState)
+		{
+			throw new NotImplementedException();
+		}
+
+		public void OnResume(IFileStorageSetupActivity activity)
+		{
+			throw new NotImplementedException();
+		}
+
+		public void OnStart(IFileStorageSetupActivity activity)
+		{
+			throw new NotImplementedException();
+		}
+
+		public void OnActivityResult(IFileStorageSetupActivity activity, int requestCode, int resultCode, Intent data)
+		{
+			throw new NotImplementedException();
+		}
+
+		public string GetDisplayName(IOConnectionInfo ioc)
+		{
+			return ioc.Path;
+		}
+
+		public string CreateFilePath(string parent, string newFilename)
+		{
+			throw new NotImplementedException();
+		}
+
+		public IOConnectionInfo GetParentPath(IOConnectionInfo ioc)
+		{
+			throw new NotImplementedException();
+		}
+
+		public IOConnectionInfo GetFilePath(IOConnectionInfo folderPath, string filename)
+		{
+			throw new NotImplementedException();
+		}
 	}
 }

src/Kp2aUnitTests/TestKp2aApp.cs

@@ -1,9 +1,11 @@
 using System;
 using System.Collections.Generic;
 using System.IO;
+using System.Net.Security;
 using Android.App;
 using Android.Content;
 using Android.OS;
+using KeePassLib.Keys;
 using KeePassLib.Serialization;
 using keepass2android;
 using keepass2android.Io;
@@ -30,18 +32,27 @@ namespace Kp2aUnitTests
 			
 		}
 
+		public virtual TestFileStorage TestFileStorage
+		{
+			get
+			{
+				if (_testFileStorage != null)
+					return _testFileStorage;
+				return (TestFileStorage) FileStorage;
+			}
+			set { _testFileStorage = value; }
+		}
+
 		public void LockDatabase(bool allowQuickUnlock = true)
 		{
 			throw new NotImplementedException();
 		}
 
-		public void LoadDatabase(IOConnectionInfo ioConnectionInfo, MemoryStream memoryStream, string password, string keyFile,
+		public void LoadDatabase(IOConnectionInfo ioConnectionInfo, MemoryStream memoryStream, CompositeKey compKey,
 		                         ProgressDialogStatusLogger statusLogger)
 		{
-			_db.LoadData(this, ioConnectionInfo, memoryStream, password, statusLogger);
-			
+			_db.LoadData(this, ioConnectionInfo, memoryStream, compKey, statusLogger);
 		}
-
 		public Database GetDb()
 		{
 			return _db;
@@ -128,10 +139,11 @@ namespace Kp2aUnitTests
 
 		
 		public bool TriggerReloadCalled;
+		private TestFileStorage _testFileStorage;
 
 		public TestKp2aApp()
 		{
-			FileStorage = new BuiltInFileStorage();
+			FileStorage = new BuiltInFileStorage(this);
 		}
 
 		public void TriggerReload(Context ctx)
@@ -139,6 +151,16 @@ namespace Kp2aUnitTests
 			TriggerReloadCalled = true;
 		}
 
+		public bool OnServerCertificateError(int sslPolicyErrors)
+		{
+			ServerCertificateErrorCalled = true;
+			return ServerCertificateErrorResponse;
+		}
+
+		public bool ServerCertificateErrorResponse { get; set; }
+
+		protected bool ServerCertificateErrorCalled { get; set; }
+
 		public void SetYesNoCancelResult(YesNoCancelResult yesNoCancelResult)
 		{
 			_yesNoCancelResult = yesNoCancelResult;

src/Kp2aUnitTests/TestLoadDb.cs

@@ -1,9 +1,7 @@
 using System;
 using System.IO;
 using System.Linq;
-using System.Threading;
 using Android.App;
-using Android.OS;
 using KeePassLib.Serialization;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
 using keepass2android;
@@ -21,8 +19,10 @@ namespace Kp2aUnitTests
 			IKp2aApp app = new TestKp2aApp();
 			app.CreateNewDatabase();
 			bool loadSuccesful = false;
-			LoadDb task = new LoadDb(app, new IOConnectionInfo() { Path = TestDbDirectory+filenameWithoutDir }, null,
-				password, keyfile, new ActionOnFinish((success, message) =>
+			var key = CreateKey(password, keyfile);
+
+			LoadDb task = new LoadDb(app, new IOConnectionInfo { Path = TestDbDirectory+filenameWithoutDir }, null,
+				key, keyfile, new ActionOnFinish((success, message) =>
 					{
 						if (!success)
 							Android.Util.Log.Debug("KP2ATest", "error loading db: " + message);
@@ -41,6 +41,8 @@ namespace Kp2aUnitTests
 		}
 
 		
+
+
 		[TestMethod]
 		public void TestLoadWithPasswordOnly()
 		{
@@ -74,11 +76,12 @@ namespace Kp2aUnitTests
 		public void LoadFromRemoteWithDomain()
 		{
 			var ioc = RemoteDomainIoc; //note: this property is defined in "TestLoadDbCredentials.cs" which is deliberately excluded from Git because the credentials are not public!
-			IKp2aApp app = new TestKp2aApp();
+			var app = new TestKp2aApp();
+			app.ServerCertificateErrorResponse = true; //accept invalid cert
 			app.CreateNewDatabase();
 			
 			bool loadSuccesful = false;
-			LoadDb task = new LoadDb(app, ioc, null, "a", null, new ActionOnFinish((success, message) =>
+			LoadDb task = new LoadDb(app, ioc, null, CreateKey("a"), null, new ActionOnFinish((success, message) =>
 				{
 					if (!success)
 						Android.Util.Log.Debug("KP2ATest", "error loading db: " + message);
@@ -95,14 +98,69 @@ namespace Kp2aUnitTests
 		}
 
 		[TestMethod]
-		public void LoadFromRemote1and1()
+		public void LoadErrorWithCertificateTrustFailure()
+		{
+			var ioc = RemoteCertFailureIoc; //note: this property is defined in "TestLoadDbCredentials.cs" which is deliberately excluded from Git because the credentials are not public!
+			var app = new TestKp2aApp();
+			app.ServerCertificateErrorResponse = false;
+			app.CreateNewDatabase();
+
+			bool loadSuccesful = false;
+			string theMessage = "";
+			LoadDb task = new LoadDb(app, ioc, null, CreateKey("test"), null, new ActionOnFinish((success, message) =>
+			{
+				if (!success)
+					Android.Util.Log.Debug("KP2ATest", "error loading db: " + message);
+				loadSuccesful = success;
+				theMessage = message;
+			})
+				);
+
+
+			ProgressTask pt = new ProgressTask(app, Application.Context, task);
+			Android.Util.Log.Debug("KP2ATest", "Running ProgressTask");
+			pt.Run();
+			pt.JoinWorkerThread();
+			Android.Util.Log.Debug("KP2ATest", "PT.run finished");
+			Assert.IsFalse(loadSuccesful, "database should not be loaded because invalid certificates are not accepted");
+			Assert.AreEqual(theMessage, UiStringKey.ErrorOcurred +" "+UiStringKey.CertificateFailure);
+
+		}
+
+		[TestMethod]
+		public void LoadWithAcceptedCertificateTrustFailure()
+		{
+			var ioc = RemoteCertFailureIoc; //note: this property is defined in "TestLoadDbCredentials.cs" which is deliberately excluded from Git because the credentials are not public!
+			var app = new TestKp2aApp();
+			app.ServerCertificateErrorResponse = true;
+			app.CreateNewDatabase();
+
+			bool loadSuccesful = false;
+			LoadDb task = new LoadDb(app, ioc, null, CreateKey("test"), null, new ActionOnFinish((success, message) =>
+			{
+				if (!success)
+					Android.Util.Log.Debug("KP2ATest", "error loading db: " + message);
+				loadSuccesful = success;
+			})
+				);
+			ProgressTask pt = new ProgressTask(app, Application.Context, task);
+			Android.Util.Log.Debug("KP2ATest", "Running ProgressTask");
+			pt.Run();
+			pt.JoinWorkerThread();
+			Android.Util.Log.Debug("KP2ATest", "PT.run finished");
+			Assert.IsTrue(loadSuccesful, "database should be loaded because invalid certificates are accepted");
+
+		}
+
+		[TestMethod]
+		public void LoadFromRemote1And1()
 		{
 			var ioc = RemoteIoc1and1; //note: this property is defined in "TestLoadDbCredentials.cs" which is deliberately excluded from Git because the credentials are not public!
 			IKp2aApp app = new TestKp2aApp();
 			app.CreateNewDatabase();
 			
 			bool loadSuccesful = false;
-			LoadDb task = new LoadDb(app, ioc, null, "test", null, new ActionOnFinish((success, message) =>
+			LoadDb task = new LoadDb(app, ioc, null, CreateKey("test"), null, new ActionOnFinish((success, message) =>
 				{
 					if (!success)
 						Android.Util.Log.Debug("KP2ATest", "error loading db: " + message);
@@ -120,7 +178,7 @@ namespace Kp2aUnitTests
 
 
 		[TestMethod]
-		public void LoadFromRemote1and1NonExisting()
+		public void LoadFromRemote1And1NonExisting()
 		{
 			var ioc = RemoteIoc1and1NonExisting; //note: this property is defined in "TestLoadDbCredentials.cs" which is deliberately excluded from Git because the credentials are not public!
 			IKp2aApp app = new TestKp2aApp();
@@ -128,7 +186,7 @@ namespace Kp2aUnitTests
 
 			bool loadSuccesful = false;
 			bool gotError = false;
-			LoadDb task = new LoadDb(app, ioc, null, "test", null, new ActionOnFinish((success, message) =>
+			LoadDb task = new LoadDb(app, ioc, null, CreateKey("test"), null, new ActionOnFinish((success, message) =>
 			{
 				if (!success)
 				{
@@ -148,7 +206,7 @@ namespace Kp2aUnitTests
 		}
 
 		[TestMethod]
-		public void LoadFromRemote1and1WrongCredentials()
+		public void LoadFromRemote1And1WrongCredentials()
 		{
 			var ioc = RemoteIoc1and1WrongCredentials; //note: this property is defined in "TestLoadDbCredentials.cs" which is deliberately excluded from Git because the credentials are not public!
 			IKp2aApp app = new TestKp2aApp();
@@ -156,7 +214,7 @@ namespace Kp2aUnitTests
 
 			bool loadSuccesful = false;
 			bool gotError = false;
-			LoadDb task = new LoadDb(app, ioc, null, "test", null, new ActionOnFinish((success, message) =>
+			LoadDb task = new LoadDb(app, ioc, null, CreateKey("test"), null, new ActionOnFinish((success, message) =>
 			{
 				if (!success)
 				{
@@ -179,7 +237,7 @@ namespace Kp2aUnitTests
 		[TestMethod]
 		public void FileNotFoundExceptionWithWebDav()
 		{
-			var fileStorage = new BuiltInFileStorage();
+			var fileStorage = new BuiltInFileStorage(new TestKp2aApp());
 			
 			//should work:
 			using (var stream = fileStorage.OpenFileForRead(RemoteIoc1and1))

src/Kp2aUnitTests/TestSaveDbCached.cs

@@ -22,12 +22,12 @@ namespace Kp2aUnitTests
 	class TestSaveDbCached: TestBase
 	{
 		private TestCacheSupervisor _testCacheSupervisor = new TestCacheSupervisor();
-		private TestFileStorage _testFileStorage = new TestFileStorage();
+		
 
 		protected override TestKp2aApp CreateTestKp2aApp()
 		{
 			TestKp2aApp app = base.CreateTestKp2aApp();
-			app.FileStorage = new CachingFileStorage(_testFileStorage, "/mnt/sdcard/kp2atest/cache/", _testCacheSupervisor);
+			app.FileStorage = new CachingFileStorage(new TestFileStorage(app), "/mnt/sdcard/kp2atest/cache/", _testCacheSupervisor);
 			return app;
 		}
 

src/Kp2aUnitTests/TestSynchronizeCachedDatabase.cs

@@ -19,13 +19,20 @@ namespace Kp2aUnitTests
 	[TestClass]
 	internal class TestSynchronizeCachedDatabase : TestBase
 	{
+		[TestInitialize]
+		public void InitTests()
+		{
+			TestFileStorage.Offline = false;
+		}
+
 		private TestCacheSupervisor _testCacheSupervisor = new TestCacheSupervisor();
-		private TestFileStorage _testFileStorage = new TestFileStorage();
 
 		protected override TestKp2aApp CreateTestKp2aApp()
 		{
 			TestKp2aApp app = base.CreateTestKp2aApp();
-			app.FileStorage = new CachingFileStorage(_testFileStorage, "/mnt/sdcard/kp2atest/cache/", _testCacheSupervisor);
+			app.TestFileStorage = new TestFileStorage(app);
+
+			app.FileStorage = new CachingFileStorage(app.TestFileStorage, "/mnt/sdcard/kp2atest/cache/", _testCacheSupervisor);
 			return app;
 		}
 
@@ -58,7 +65,7 @@ namespace Kp2aUnitTests
 			Assert.AreEqual(resultMessage, app.GetResourceString(UiStringKey.FilesInSync));
 
 			//go offline:
-			_testFileStorage.Offline = true;
+			TestFileStorage.Offline = true;
 
 			//sync when offline (->error)
 			Synchronize(app, out wasSuccessful, out resultMessage);
@@ -73,7 +80,7 @@ namespace Kp2aUnitTests
 			_testCacheSupervisor.AssertSingleCall(TestCacheSupervisor.CouldntSaveToRemoteId);
 
 			//go online again:
-			_testFileStorage.Offline = false;
+			TestFileStorage.Offline = false;
 
 			//sync with local changes only (-> upload):
 			Synchronize(app, out wasSuccessful, out resultMessage);
@@ -81,10 +88,10 @@ namespace Kp2aUnitTests
 			Assert.AreEqual(resultMessage, app.GetResourceString(UiStringKey.SynchronizedDatabaseSuccessfully));
 
 			//ensure both files are identical and up to date now:
-			_testFileStorage.Offline = true;
+			TestFileStorage.Offline = true;
 			var appOfflineLoaded = LoadDatabase(DefaultFilename, DefaultPassword, DefaultKeyfile);
 			_testCacheSupervisor.AssertSingleCall(TestCacheSupervisor.CouldntOpenFromRemoteId);
-			_testFileStorage.Offline = false;
+			TestFileStorage.Offline = false;
 			var appRemoteLoaded = LoadDatabase(DefaultFilename, DefaultPassword, DefaultKeyfile);
 			_testCacheSupervisor.AssertSingleCall(TestCacheSupervisor.LoadedFromRemoteInSyncId);
 
@@ -92,6 +99,8 @@ namespace Kp2aUnitTests
 			AssertDatabasesAreEqual(app.GetDb().KpDatabase, appRemoteLoaded.GetDb().KpDatabase);
 		}
 
+		
+
 		[TestMethod]
 		public void TestSyncWhenRemoteDeleted()
 		{
@@ -133,11 +142,11 @@ namespace Kp2aUnitTests
 			_testCacheSupervisor.AssertSingleCall(TestCacheSupervisor.LoadedFromRemoteInSyncId);
 
 			var app2 = LoadDatabase(DefaultFilename, DefaultPassword, DefaultKeyfile);
-			app2.FileStorage = _testFileStorage; //give app2 direct access to the remote file
+			app2.FileStorage = app.TestFileStorage; //give app2 direct access to the remote file
 			_testCacheSupervisor.AssertSingleCall(TestCacheSupervisor.LoadedFromRemoteInSyncId);
 
 			//go offline:
-			_testFileStorage.Offline = true;
+			TestFileStorage.Offline = true;
 
 
 			string resultMessage;
@@ -153,7 +162,7 @@ namespace Kp2aUnitTests
 			_testCacheSupervisor.AssertSingleCall(TestCacheSupervisor.CouldntSaveToRemoteId);
 
 			//go online again:
-			_testFileStorage.Offline = false;
+			TestFileStorage.Offline = false;
 			
 			//...and remote only for "app2":
 			SaveDatabase(app2);

src/keepass2android/Properties/AndroidManifest_net.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<manifest xmlns:android="http://schemas.android.com/apk/res/android" android:versionCode="30" android:versionName="0.9.2" package="keepass2android.keepass2android" android:installLocation="auto">
+<manifest xmlns:android="http://schemas.android.com/apk/res/android" android:versionCode="31" android:versionName="0.9.2-r2" package="keepass2android.keepass2android" android:installLocation="auto">
 	<uses-sdk android:minSdkVersion="8" android:targetSdkVersion="14" />
 	<permission android:description="@string/permission_desc" android:icon="@drawable/ic_launcher" android:label="KP2A internal file browsing" android:name="keepass2android.keepass2android.permission.KP2aInternalFileBrowsing" android:protectionLevel="signature" />
 	<application android:label="keepass2android" android:icon="@drawable/ic_launcher">

src/keepass2android/Resources/values/config.xml

@@ -89,6 +89,7 @@
 	<string name="UseFileTransactions_key">UseFileTransactions</string>
 	<string name="LockWhenScreenOff_key">LockWhenScreenOff</string>
 	<string name="UseOfflineCache_key">UseOfflineCache</string>
+	<string name="AcceptAllServerCertificates_key">AcceptAllServerCertificates</string>
 	<string name="CheckForFileChangesOnSave_key">CheckForFileChangesOnSave</string>
 
 	<string name="MarketURL">market://details?id=</string>
@@ -122,6 +123,13 @@
     	<item>28</item>
     </string-array>
 
+	<string name="AcceptAllServerCertificates_default">WARN</string>
+	<string-array name="AcceptAllServerCertificates_values">
+		<item>IGNORE</item>
+		<item>WARN</item>
+		<item>ERROR</item>
+	</string-array>
+
 	<string name="ShowUnlockedNotification_key">ShowUnlockedNotification</string>
 	<bool name="ShowUnlockedNotification_default">true</bool>
 

src/keepass2android/Resources/values/strings.xml

@@ -239,6 +239,11 @@
   <string name="LockWhenScreenOff_summary">Lock the database when screen is switched off.</string>
 	<string name="UseOfflineCache_title">Database caching</string>
 	<string name="UseOfflineCache_summary">Keep a copy of remote database files in the application cache directory. This allows to use remote databases even when offline.</string>
+
+	<string name="AcceptAllServerCertificates_title">SSL certificates</string>
+	<string name="AcceptAllServerCertificates_summary">Define the behavior when certificate validation fails. Note: you can install certificates on your device if validation fails!</string>
+	
+	
 	<string name="ClearOfflineCache_title">Clear cache?</string>
 	<string name="ClearOfflineCache_question">This will delete all cached database files. Any changes you made while being offline which have not yet been synchronized will be lost! Continue?</string>
   <string name="CheckForFileChangesOnSave_title">Check for modifications</string>
@@ -373,15 +378,19 @@
 
 	<string name="loading">Loading…</string>
 
+	<string name="CertificateWarning">Warning: Server certificate validation failed: %1$s. Install appropriate root certificate on your device or see settings!</string>
+	<string name="CertificateFailure">Error: Server certificate validation failed! Install appropriate root certificate on your device or see settings!</string>
+	
 	<string name="ChangeLog_title">Change log</string>
 
 	<string name="ChangeLog_0_9_2">
-		<b>Version 0.9.2b (preview)</b>\n
+		<b>Version 0.9.2</b>\n
 		* Added OTP support (compatible with OtpKeyProv plugin)\n
 		* Integrated NFC support for OTPs from YubiKey NEO \n
 		* Several UI improvements\n
 		* Integrated Keepass 2.24 library\n
 		* Added option to kill the app process (see settings)\n
+		* Improved SSL certificate validation\n
 		* Bug fixes\n
 	</string>
 
@@ -501,4 +510,10 @@ Initial public release
 		<item>Password + OTP</item>
 		<item>Password + OTP secret (recovery mode)</item>
 	</string-array>
+	<string-array name="AcceptAllServerCertificates_options">
+		<item>Ignore certificate validation failures</item>
+		<item>Warn when validation fails</item>
+		<item>Do not accept invalid certificates</item>
+	</string-array>
+
 </resources>

src/keepass2android/Resources/xml/preferences.xml

@@ -204,6 +204,16 @@
 				  android:defaultValue="true"
 				  android:title="@string/UseOfflineCache_title"
 				  android:key="@string/UseOfflineCache_key" />
+			<ListPreference
+			  android:key="@string/AcceptAllServerCertificates_key"
+			  android:title="@string/AcceptAllServerCertificates_title"
+			  android:summary="@string/AcceptAllServerCertificates_summary"
+			  android:entries="@array/AcceptAllServerCertificates_options"
+			  android:entryValues="@array/AcceptAllServerCertificates_values"
+			  android:dialogTitle="@string/AcceptAllServerCertificates_title"
+			  android:defaultValue="@string/AcceptAllServerCertificates_default"/>
+			
+		
 			<CheckBoxPreference
 				android:enabled="true"
 				  android:persistent="true"

src/keepass2android/app/App.cs

@@ -353,7 +353,7 @@ namespace keepass2android
 		public IFileStorage GetFileStorage(IOConnectionInfo iocInfo)
 		{
 			if (iocInfo.IsLocalFile())
-				return new BuiltInFileStorage();
+				return new BuiltInFileStorage(this);
 			else
 			{
 				IFileStorage innerFileStorage = GetCloudFileStorage(iocInfo);
@@ -399,7 +399,7 @@ namespace keepass2android
 							new GoogleDriveFileStorage(Application.Context, this),
 							new SkyDriveFileStorage(Application.Context, this),
 #endif
-							new BuiltInFileStorage()
+							new BuiltInFileStorage(this)
 						};
 				}
 				return _fileStorages;
@@ -416,6 +416,61 @@ namespace keepass2android
 		}
 
 		
+
+		private String GetProblemMessage(BuiltInFileStorage.CertificateProblem problem)
+		{
+			String problemMessage;
+			const BuiltInFileStorage.CertificateProblem problemList = new BuiltInFileStorage.CertificateProblem();
+			string problemCodeName = Enum.GetName(typeof(BuiltInFileStorage.CertificateProblem), problem);
+				
+			if (problemCodeName != null)
+				problemMessage = problemCodeName;
+			else
+				problemMessage = "Unknown Certificate Problem";
+			return problemMessage;
+		}
+
+		enum ValidationMode
+		{
+			Ignore, Warn, Error
+		}
+
+		public bool OnServerCertificateError(int certificateProblem)
+		{
+			var prefs = PreferenceManager.GetDefaultSharedPreferences(Application.Context);
+
+			ValidationMode validationMode = ValidationMode.Warn;
+			
+			string strValMode = prefs.GetString(Application.Context.Resources.GetString(Resource.String.AcceptAllServerCertificates_key),
+												 Application.Context.Resources.GetString(Resource.String.AcceptAllServerCertificates_default));
+
+			if (strValMode == "IGNORE")
+				validationMode = ValidationMode.Ignore;
+			else if (strValMode == "ERROR")
+				validationMode = ValidationMode.Error;
+			;
+
+			switch (validationMode)
+			{
+				case ValidationMode.Ignore:
+					return true;
+				case ValidationMode.Warn:
+					ShowToast(Application.Context.GetString(Resource.String.CertificateWarning,
+				                                        new Java.Lang.Object[]
+					                                        {
+						                                        GetProblemMessage(
+							                                        (BuiltInFileStorage.CertificateProblem)
+							                                        (System.UInt32) certificateProblem)
+					                                        }));
+					return true;
+				case ValidationMode.Error:
+					return false;
+				default:
+					throw new ArgumentOutOfRangeException();
+			}
+		}
+
+
 		internal void OnTerminate()
         {
             if (_db != null)
@@ -492,7 +547,7 @@ namespace keepass2android
 
 		public void ClearOfflineCache()
 		{
-			new CachingFileStorage(new BuiltInFileStorage(), Application.Context.CacheDir.Path, this).ClearCache();
+			new CachingFileStorage(new BuiltInFileStorage(this), Application.Context.CacheDir.Path, this).ClearCache();
 		}
 
 		public IFileStorage GetFileStorage(string protocolId)
@@ -508,7 +563,7 @@ namespace keepass2android
 		{
 
 			if (iocInfo.IsLocalFile())
-				return new BuiltInFileStorage();
+				return new BuiltInFileStorage(this);
 			else
 			{
 				IFileStorage innerFileStorage = GetCloudFileStorage(iocInfo);

src/keepass2android/keepass2android.csproj

@@ -29,7 +29,7 @@
     <DebugType>full</DebugType>
     <Optimize>False</Optimize>
     <OutputPath>bin\Debug</OutputPath>
-    <DefineConstants>DEBUG;EXCLUDE_TWOFISH;INCLUDE_KEYBOARD;EXCLUDE_KEYTRANSFORM;INCLUDE_FILECHOOSER;INCLUDE_JAVAFILESTORAGE</DefineConstants>
+    <DefineConstants>DEBUG;EXCLUDE_TWOFISH;EXCLUDE_KEYBOARD;EXCLUDE_KEYTRANSFORM;EXCLUDE_FILECHOOSER;EXCLUDE_JAVAFILESTORAGE</DefineConstants>
     <ErrorReport>prompt</ErrorReport>
     <WarningLevel>4</WarningLevel>
     <ConsolePause>False</ConsolePause>