Update 0.8.2

Fixes slow range requests on OS X, as WebDAVFS sometimes processes responses only after closing the connection, even though "keep-alive" is requested.

.travis.yml

@@ -1,7 +1,8 @@
 language: java
 jdk:
 - oraclejdk8
-script: mvn -fmain/pom.xml clean package
+before_install: "curl -L --cookie 'oraclelicense=accept-securebackup-cookie;'  http://download.oracle.com/otn-pub/java/jce/8/jce_policy-8.zip -o /tmp/policy.zip && sudo unzip -j -o /tmp/policy.zip *.jar -d `jdk_switcher home oraclejdk8`/jre/lib/security && rm /tmp/policy.zip"
+script: mvn -fmain/pom.xml -Puber-jar clean package
 notifications:
   webhooks:
     urls:
@@ -11,9 +12,10 @@ notifications:
     on_start: false
 deploy:
   provider: releases
+  prerelease: true
   api_key:
     secure: ZjE1j93v3qbPIe2YbmhS319aCbMdLQw0HuymmluTurxXsZtn9D4t2+eTr99vBVxGRuB5lzzGezPR5zjk5W7iHF7xhwrawXrFzr2rPJWzWFt0aM+Ry2njU1ROTGGXGTbv4anWeBlgMxLEInTAy/9ytOGNJlec83yc0THpOY2wxnk=
-  file: main/ui/target/dist/Cryptomator.jar
+  file: main/uber-jar/target/Cryptomator-$TRAVIS_TAG.jar
   skip_cleanup: true
   on:
     repo: cryptomator/cryptomator

README.md

@@ -46,7 +46,7 @@ If you want to take a look at the current beta version, go ahead and get your co
 apt-get install oracle-java8-installer oracle-java8-unlimited-jce-policy fakeroot maven git
 git clone https://github.com/cryptomator/cryptomator.git
 cd cryptomator/main
-git checkout v0.6.0
+git checkout 0.7.1
 mvn clean install -Pdebian
 ```
 

main/core/pom.xml

@@ -12,16 +12,14 @@
 	<parent>
 		<groupId>org.cryptomator</groupId>
 		<artifactId>main</artifactId>
-		<version>0.7.0</version>
+		<version>0.8.2</version>
 	</parent>
 	<artifactId>core</artifactId>
 	<name>Cryptomator WebDAV and I/O module</name>
 
 	<properties>
-		<jetty.version>9.2.10.v20150310</jetty.version>
-		<jackrabbit.version>2.10.1</jackrabbit.version>
-		<commons.transaction.version>1.2</commons.transaction.version>
-		<jta.version>1.1</jta.version>
+		<jetty.version>9.3.3.v20150827</jetty.version>
+		<jackrabbit.version>2.11.0</jackrabbit.version>
 	</properties>
 
 	<dependencies>
@@ -29,6 +27,11 @@
 			<groupId>org.cryptomator</groupId>
 			<artifactId>crypto-api</artifactId>
 		</dependency>
+		<dependency>
+			<groupId>org.cryptomator</groupId>
+			<artifactId>crypto-aes</artifactId>
+			<scope>test</scope>
+		</dependency>
 
 		<!-- Jetty (Servlet Container) -->
 		<dependency>
@@ -41,6 +44,11 @@
 			<artifactId>jetty-webapp</artifactId>
 			<version>${jetty.version}</version>
 		</dependency>
+		<dependency>
+			<groupId>commons-httpclient</groupId>
+			<artifactId>commons-httpclient</artifactId>
+			<scope>test</scope>
+		</dependency>
 
 		<!-- Jackrabbit -->
 		<dependency>
@@ -48,13 +56,13 @@
 			<artifactId>jackrabbit-webdav</artifactId>
 			<version>${jackrabbit.version}</version>
 		</dependency>
-	
+
 		<!-- Guava -->
 		<dependency>
 			<groupId>com.google.guava</groupId>
 			<artifactId>guava</artifactId>
 		</dependency>
-	
+
 		<!-- I/O -->
 		<dependency>
 			<groupId>commons-io</groupId>
@@ -64,7 +72,7 @@
 			<groupId>org.apache.commons</groupId>
 			<artifactId>commons-lang3</artifactId>
 		</dependency>
-		
+
 		<!-- JSON -->
 		<dependency>
 			<groupId>com.fasterxml.jackson.core</groupId>

main/core/src/main/java/org/cryptomator/webdav/WebDavServer.java

@@ -40,6 +40,7 @@ public final class WebDavServer {
 	private static final int MAX_THREADS = 200;
 	private static final int MIN_THREADS = 4;
 	private static final int THREAD_IDLE_SECONDS = 20;
+	private static final int CONNECTION_IDLE_MILLIS = 100; // idle connection slow down random access on WebDAVFS for some reason. reconnect overhead can be tolerated
 	private final Server server;
 	private final ServerConnector localConnector;
 	private final ContextHandlerCollection servletCollection;
@@ -50,11 +51,14 @@ public final class WebDavServer {
 		server = new Server(tp);
 		localConnector = new ServerConnector(server);
 		localConnector.setHost(LOCALHOST);
+		localConnector.setIdleTimeout(CONNECTION_IDLE_MILLIS);
 		servletCollection = new ContextHandlerCollection();
 
-		final ServletContextHandler servletContext = new ServletContextHandler(servletCollection, "/", ServletContextHandler.NO_SESSIONS);
-		final ServletHolder servlet = new ServletHolder(WindowsSucksServlet.class);
-		servletContext.addServlet(servlet, "/");
+		if (SystemUtils.IS_OS_WINDOWS) {
+			final ServletContextHandler servletContext = new ServletContextHandler(servletCollection, "/", ServletContextHandler.NO_SESSIONS);
+			final ServletHolder servlet = new ServletHolder(WindowsSucksServlet.class);
+			servletContext.addServlet(servlet, "/");
+		}
 
 		server.setConnectors(new Connector[] {localConnector});
 		server.setHandler(servletCollection);
@@ -84,13 +88,11 @@ public final class WebDavServer {
 	/**
 	 * @param workDir Path of encrypted folder.
 	 * @param cryptor A fully initialized cryptor instance ready to en- or decrypt streams.
-	 * @param failingMacCollection A (observable, thread-safe) collection, to which the names of resources are written, whose MAC
-	 *            authentication fails.
-	 * @param name The name of the folder. Must be non-empty and only contain any of
-	 *            _ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789
+	 * @param failingMacCollection A (observable, thread-safe) collection, to which the names of resources are written, whose MAC authentication fails.
+	 * @param name The name of the folder. Must be non-empty and only contain any of _ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789
 	 * @return servlet
 	 */
-	public ServletLifeCycleAdapter createServlet(final Path workDir, final Cryptor cryptor, final Collection<String> failingMacCollection, final String name) {
+	public ServletLifeCycleAdapter createServlet(final Path workDir, final Cryptor cryptor, final Collection<String> failingMacCollection, final Collection<String> whitelistedResourceCollection, final String name) {
 		try {
 			if (StringUtils.isEmpty(name)) {
 				throw new IllegalArgumentException("name empty");
@@ -101,7 +103,7 @@ public final class WebDavServer {
 			final URI uri = new URI(null, null, localConnector.getHost(), localConnector.getLocalPort(), "/" + UUID.randomUUID().toString() + "/" + name, null, null);
 
 			final ServletContextHandler servletContext = new ServletContextHandler(servletCollection, uri.getRawPath(), ServletContextHandler.SESSIONS);
-			final ServletHolder servlet = getWebDavServletHolder(workDir.toString(), cryptor, failingMacCollection);
+			final ServletHolder servlet = getWebDavServletHolder(workDir.toString(), cryptor, failingMacCollection, whitelistedResourceCollection);
 			servletContext.addServlet(servlet, "/*");
 
 			servletCollection.mapContexts();
@@ -113,8 +115,8 @@ public final class WebDavServer {
 		}
 	}
 
-	private ServletHolder getWebDavServletHolder(final String workDir, final Cryptor cryptor, final Collection<String> failingMacCollection) {
-		final ServletHolder result = new ServletHolder("Cryptomator-WebDAV-Servlet", new WebDavServlet(cryptor, failingMacCollection));
+	private ServletHolder getWebDavServletHolder(final String workDir, final Cryptor cryptor, final Collection<String> failingMacCollection, final Collection<String> whitelistedResourceCollection) {
+		final ServletHolder result = new ServletHolder("Cryptomator-WebDAV-Servlet", new WebDavServlet(cryptor, failingMacCollection, whitelistedResourceCollection));
 		result.setInitParameter(WebDavServlet.CFG_FS_ROOT, workDir);
 		return result;
 	}

main/core/src/main/java/org/cryptomator/webdav/jackrabbit/CleartextLocatorFactory.java

@@ -79,7 +79,7 @@ public class CleartextLocatorFactory implements DavLocatorFactory {
 			final String encodedResourcePath = EncodeUtil.escapePath(getResourcePath());
 			final String fullPrefix = pathPrefix.endsWith("/") ? pathPrefix : pathPrefix + "/";
 			final String href = fullPrefix.concat(encodedResourcePath);
-			assert !href.endsWith("/");
+			assert href.equals(fullPrefix) || !href.endsWith("/");
 			if (isCollection) {
 				return href.concat("/");
 			} else {

main/core/src/main/java/org/cryptomator/webdav/jackrabbit/CryptoResourceFactory.java

@@ -5,10 +5,13 @@ import java.nio.file.FileAlreadyExistsException;
 import java.nio.file.FileSystems;
 import java.nio.file.Files;
 import java.nio.file.Path;
-import java.util.concurrent.ExecutorService;
+import java.nio.file.attribute.FileTime;
+import java.time.format.DateTimeParseException;
 
-import org.apache.commons.httpclient.HttpStatus;
 import org.apache.commons.io.FilenameUtils;
+import org.apache.commons.lang3.StringUtils;
+import org.apache.commons.lang3.tuple.ImmutablePair;
+import org.apache.commons.lang3.tuple.Pair;
 import org.apache.jackrabbit.webdav.DavException;
 import org.apache.jackrabbit.webdav.DavMethods;
 import org.apache.jackrabbit.webdav.DavResource;
@@ -21,22 +24,25 @@ import org.apache.jackrabbit.webdav.lock.LockManager;
 import org.apache.jackrabbit.webdav.lock.SimpleLockManager;
 import org.apache.logging.log4j.util.Strings;
 import org.cryptomator.crypto.Cryptor;
+import org.cryptomator.webdav.exceptions.IORuntimeException;
 import org.eclipse.jetty.http.HttpHeader;
 
 public class CryptoResourceFactory implements DavResourceFactory, FileConstants {
 
+	private static final String RANGE_BYTE_PREFIX = "bytes=";
+	private static final char RANGE_SET_SEP = ',';
+	private static final char RANGE_SEP = '-';
+
 	private final LockManager lockManager = new SimpleLockManager();
 	private final Cryptor cryptor;
 	private final CryptoWarningHandler cryptoWarningHandler;
-	private final ExecutorService backgroundTaskExecutor;
 	private final Path dataRoot;
 	private final FilenameTranslator filenameTranslator;
 
-	CryptoResourceFactory(Cryptor cryptor, CryptoWarningHandler cryptoWarningHandler, ExecutorService backgroundTaskExecutor, String vaultRoot) {
+	CryptoResourceFactory(Cryptor cryptor, CryptoWarningHandler cryptoWarningHandler, String vaultRoot) {
 		Path vaultRootPath = FileSystems.getDefault().getPath(vaultRoot);
 		this.cryptor = cryptor;
 		this.cryptoWarningHandler = cryptoWarningHandler;
-		this.backgroundTaskExecutor = backgroundTaskExecutor;
 		this.dataRoot = vaultRootPath.resolve("d");
 		this.filenameTranslator = new FilenameTranslator(cryptor, vaultRootPath);
 	}
@@ -47,20 +53,36 @@ public class CryptoResourceFactory implements DavResourceFactory, FileConstants
 			return createRootDirectory(locator, request.getDavSession());
 		}
 
-		final Path filePath = getEncryptedFilePath(locator.getResourcePath());
-		final Path dirFilePath = getEncryptedDirectoryFilePath(locator.getResourcePath());
-		final String rangeHeader = request.getHeader(HttpHeader.RANGE.asString());
-		if (Files.exists(dirFilePath) || DavMethods.METHOD_MKCOL.equals(request.getMethod())) {
-			return createDirectory(locator, request.getDavSession(), dirFilePath);
-		} else if (Files.exists(filePath) && DavMethods.METHOD_GET.equals(request.getMethod()) && rangeHeader != null) {
-			response.setStatus(HttpStatus.SC_PARTIAL_CONTENT);
-			return createFilePart(locator, request.getDavSession(), request, filePath);
-		} else if (Files.exists(filePath) || DavMethods.METHOD_PUT.equals(request.getMethod())) {
-			return createFile(locator, request.getDavSession(), filePath);
-		} else {
-			// e.g. for MOVE operations:
-			return createNonExisting(locator, request.getDavSession(), filePath, dirFilePath);
+		try {
+			final Path filePath = getEncryptedFilePath(locator.getResourcePath(), false);
+			final Path dirFilePath = getEncryptedDirectoryFilePath(locator.getResourcePath(), false);
+			final String rangeHeader = request.getHeader(HttpHeader.RANGE.asString());
+			final String ifRangeHeader = request.getHeader(HttpHeader.IF_RANGE.asString());
+			if (Files.exists(dirFilePath) || DavMethods.METHOD_MKCOL.equals(request.getMethod())) {
+				// DIRECTORY
+				return createDirectory(locator, request.getDavSession(), dirFilePath);
+			} else if (Files.exists(filePath) && DavMethods.METHOD_GET.equals(request.getMethod()) && rangeHeader != null && isRangeSatisfiable(rangeHeader) && isIfRangePreconditionFulfilled(ifRangeHeader, filePath)) {
+				// FILE RANGE
+				final Pair<String, String> requestRange = getRequestRange(rangeHeader);
+				response.setStatus(DavServletResponse.SC_PARTIAL_CONTENT);
+				return createFilePart(locator, request.getDavSession(), requestRange, filePath);
+			} else if (Files.exists(filePath) && DavMethods.METHOD_GET.equals(request.getMethod()) && rangeHeader != null && isRangeSatisfiable(rangeHeader) && !isIfRangePreconditionFulfilled(ifRangeHeader, filePath)) {
+				// FULL FILE (if-range not fulfilled)
+				return createFile(locator, request.getDavSession(), filePath);
+			} else if (Files.exists(filePath) && DavMethods.METHOD_GET.equals(request.getMethod()) && rangeHeader != null && !isRangeSatisfiable(rangeHeader)) {
+				// FULL FILE (unsatisfiable range)
+				response.setStatus(DavServletResponse.SC_REQUESTED_RANGE_NOT_SATISFIABLE);
+				final EncryptedFile file = createFile(locator, request.getDavSession(), filePath);
+				response.addHeader(HttpHeader.CONTENT_RANGE.asString(), "bytes */" + file.getContentLength());
+				return file;
+			} else if (Files.exists(filePath) || DavMethods.METHOD_PUT.equals(request.getMethod())) {
+				// FULL FILE (as requested)
+				return createFile(locator, request.getDavSession(), filePath);
+			}
+		} catch (NonExistingParentException e) {
+			// return non-existing
 		}
+		return createNonExisting(locator, request.getDavSession());
 	}
 
 	@Override
@@ -69,16 +91,18 @@ public class CryptoResourceFactory implements DavResourceFactory, FileConstants
 			return createRootDirectory(locator, session);
 		}
 
-		final Path filePath = getEncryptedFilePath(locator.getResourcePath());
-		final Path dirFilePath = getEncryptedDirectoryFilePath(locator.getResourcePath());
-		if (Files.exists(dirFilePath)) {
-			return createDirectory(locator, session, dirFilePath);
-		} else if (Files.exists(filePath)) {
-			return createFile(locator, session, filePath);
-		} else {
-			// e.g. for MOVE operations:
-			return createNonExisting(locator, session, filePath, dirFilePath);
+		try {
+			final Path filePath = getEncryptedFilePath(locator.getResourcePath(), false);
+			final Path dirFilePath = getEncryptedDirectoryFilePath(locator.getResourcePath(), false);
+			if (Files.exists(dirFilePath)) {
+				return createDirectory(locator, session, dirFilePath);
+			} else if (Files.exists(filePath)) {
+				return createFile(locator, session, filePath);
+			}
+		} catch (NonExistingParentException e) {
+			// return non-existing
 		}
+		return createNonExisting(locator, session);
 	}
 
 	DavResource createChildDirectoryResource(DavResourceLocator locator, DavSession session, Path existingDirectoryFile) throws DavException {
@@ -90,42 +114,109 @@ public class CryptoResourceFactory implements DavResourceFactory, FileConstants
 	}
 
 	/**
-	 * @return Absolute file path for a given cleartext file resourcePath.
-	 * @throws IOException
+	 * @return <code>true</code> if a partial response should be generated according to an If-Range precondition.
 	 */
-	private Path getEncryptedFilePath(String relativeCleartextPath) throws DavException {
+	private boolean isIfRangePreconditionFulfilled(String ifRangeHeader, Path filePath) throws DavException {
+		if (ifRangeHeader == null) {
+			// no header set -> fulfilled implicitly
+			return true;
+		} else {
+			try {
+				final FileTime expectedTime = FileTimeUtils.fromRfc1123String(ifRangeHeader);
+				final FileTime actualTime = Files.getLastModifiedTime(filePath);
+				return expectedTime.compareTo(actualTime) == 0;
+			} catch (DateTimeParseException e) {
+				throw new DavException(DavServletResponse.SC_BAD_REQUEST, "Unsupported If-Range header: " + ifRangeHeader);
+			} catch (IOException e) {
+				throw new DavException(DavServletResponse.SC_INTERNAL_SERVER_ERROR, e);
+			}
+		}
+	}
+
+	/**
+	 * @return <code>true</code> if and only if exactly one byte range has been requested.
+	 */
+	private boolean isRangeSatisfiable(String rangeHeader) {
+		assert rangeHeader != null;
+		if (!rangeHeader.startsWith(RANGE_BYTE_PREFIX)) {
+			return false;
+		}
+		final String byteRangeSet = StringUtils.removeStartIgnoreCase(rangeHeader, RANGE_BYTE_PREFIX);
+		final String[] byteRanges = StringUtils.split(byteRangeSet, RANGE_SET_SEP);
+		if (byteRanges.length != 1) {
+			return false;
+		}
+		return true;
+	}
+
+	/**
+	 * Processes the given range header field, if it is supported. Only headers containing a single byte range are supported.<br/>
+	 * <code>
+	 * bytes=100-200<br/>
+	 * bytes=-500<br/>
+	 * bytes=1000-
+	 * </code>
+	 * 
+	 * @return Tuple of left and right range.
+	 * @throws DavException HTTP statuscode 400 for malformed requests.
+	 * @throws IllegalArgumentException If the given rangeHeader is not satisfiable. Check with {@link #isRangeSatisfiable(String)} before.
+	 */
+	private Pair<String, String> getRequestRange(String rangeHeader) throws DavException {
+		assert rangeHeader != null;
+		if (!rangeHeader.startsWith(RANGE_BYTE_PREFIX)) {
+			throw new IllegalArgumentException("Unsatisfiable range. Should have generated 416 resonse.");
+		}
+		final String byteRangeSet = StringUtils.removeStartIgnoreCase(rangeHeader, RANGE_BYTE_PREFIX);
+		final String[] byteRanges = StringUtils.split(byteRangeSet, RANGE_SET_SEP);
+		if (byteRanges.length != 1) {
+			throw new IllegalArgumentException("Unsatisfiable range. Should have generated 416 resonse.");
+		}
+		final String byteRange = byteRanges[0];
+		final String[] bytePos = StringUtils.splitPreserveAllTokens(byteRange, RANGE_SEP);
+		if (bytePos.length != 2 || bytePos[0].isEmpty() && bytePos[1].isEmpty()) {
+			throw new DavException(DavServletResponse.SC_BAD_REQUEST, "malformed range header: " + rangeHeader);
+		}
+		return new ImmutablePair<>(bytePos[0], bytePos[1]);
+	}
+
+	/**
+	 * @return Absolute file path for a given cleartext file resourcePath.
+	 * @throws NonExistingParentException If one ancestor of the enrypted path is missing
+	 */
+	Path getEncryptedFilePath(String relativeCleartextPath, boolean createNonExisting) throws NonExistingParentException {
 		final String parentCleartextPath = FilenameUtils.getPathNoEndSeparator(relativeCleartextPath);
-		final Path parent = createEncryptedDirectoryPath(parentCleartextPath);
+		final Path parent = getEncryptedDirectoryPath(parentCleartextPath, createNonExisting);
 		final String cleartextFilename = FilenameUtils.getName(relativeCleartextPath);
 		try {
 			final String encryptedFilename = filenameTranslator.getEncryptedFilename(cleartextFilename);
 			return parent.resolve(encryptedFilename);
 		} catch (IOException e) {
-			throw new DavException(DavServletResponse.SC_INTERNAL_SERVER_ERROR, e);
+			throw new IORuntimeException(e);
 		}
 	}
 
 	/**
 	 * @return Absolute file path for a given cleartext file resourcePath.
-	 * @throws IOException
+	 * @throws NonExistingParentException If one ancestor of the enrypted path is missing
 	 */
-	private Path getEncryptedDirectoryFilePath(String relativeCleartextPath) throws DavException {
+	Path getEncryptedDirectoryFilePath(String relativeCleartextPath, boolean createNonExisting) throws NonExistingParentException {
 		final String parentCleartextPath = FilenameUtils.getPathNoEndSeparator(relativeCleartextPath);
-		final Path parent = createEncryptedDirectoryPath(parentCleartextPath);
+		final Path parent = getEncryptedDirectoryPath(parentCleartextPath, createNonExisting);
 		final String cleartextFilename = FilenameUtils.getName(relativeCleartextPath);
 		try {
 			final String encryptedFilename = filenameTranslator.getEncryptedDirFileName(cleartextFilename);
 			return parent.resolve(encryptedFilename);
 		} catch (IOException e) {
-			throw new DavException(DavServletResponse.SC_INTERNAL_SERVER_ERROR, e);
+			throw new IORuntimeException(e);
 		}
 	}
-
+	
 	/**
+	 * @param createNonExisting if <code>false</code>, a {@link NonExistingParentException} will be thrown for missing ancestors.
 	 * @return Absolute directory path for a given cleartext directory resourcePath.
-	 * @throws IOException
+	 * @throws NonExistingParentException if one ancestor directory is missing.
 	 */
-	private Path createEncryptedDirectoryPath(String relativeCleartextPath) throws DavException {
+	private Path getEncryptedDirectoryPath(String relativeCleartextPath, boolean createNonExisting) throws NonExistingParentException {
 		assert Strings.isEmpty(relativeCleartextPath) || !relativeCleartextPath.endsWith("/");
 		try {
 			final Path result;
@@ -135,10 +226,13 @@ public class CryptoResourceFactory implements DavResourceFactory, FileConstants
 				result = dataRoot.resolve(fixedRootDirectory);
 			} else {
 				final String parentCleartextPath = FilenameUtils.getPathNoEndSeparator(relativeCleartextPath);
-				final Path parent = createEncryptedDirectoryPath(parentCleartextPath);
+				final Path parent = getEncryptedDirectoryPath(parentCleartextPath, createNonExisting);
 				final String cleartextFilename = FilenameUtils.getName(relativeCleartextPath);
 				final String encryptedFilename = filenameTranslator.getEncryptedDirFileName(cleartextFilename);
 				final Path directoryFile = parent.resolve(encryptedFilename);
+				if (!createNonExisting && !Files.exists(directoryFile)) {
+					throw new NonExistingParentException();
+				}
 				final String directoryId = filenameTranslator.getDirectoryId(directoryFile, true);
 				final String directory = cryptor.encryptDirectoryPath(directoryId, FileSystems.getDefault().getSeparator());
 				result = dataRoot.resolve(directory);
@@ -146,12 +240,12 @@ public class CryptoResourceFactory implements DavResourceFactory, FileConstants
 			Files.createDirectories(result);
 			return result;
 		} catch (IOException e) {
-			throw new DavException(DavServletResponse.SC_INTERNAL_SERVER_ERROR, e);
+			throw new IORuntimeException(e);
 		}
 	}
 
-	private EncryptedFile createFilePart(DavResourceLocator locator, DavSession session, DavServletRequest request, Path filePath) {
-		return new EncryptedFilePart(this, locator, session, request, lockManager, cryptor, cryptoWarningHandler, backgroundTaskExecutor, filePath);
+	private EncryptedFile createFilePart(DavResourceLocator locator, DavSession session, Pair<String, String> requestRange, Path filePath) {
+		return new EncryptedFilePart(this, locator, session, requestRange, lockManager, cryptor, cryptoWarningHandler, filePath);
 	}
 
 	private EncryptedFile createFile(DavResourceLocator locator, DavSession session, Path filePath) {
@@ -178,8 +272,14 @@ public class CryptoResourceFactory implements DavResourceFactory, FileConstants
 		return new EncryptedDir(this, locator, session, lockManager, cryptor, filenameTranslator, filePath);
 	}
 
-	private NonExistingNode createNonExisting(DavResourceLocator locator, DavSession session, Path filePath, Path dirFilePath) {
-		return new NonExistingNode(this, locator, session, lockManager, cryptor, filePath, dirFilePath);
+	private NonExistingNode createNonExisting(DavResourceLocator locator, DavSession session) {
+		return new NonExistingNode(this, locator, session, lockManager, cryptor);
+	}
+	
+	static class NonExistingParentException extends Exception {
+		
+		private static final long serialVersionUID = 4421121746624627094L;
+		
 	}
 
 }

main/core/src/main/java/org/cryptomator/webdav/jackrabbit/CryptoWarningHandler.java

@@ -5,15 +5,22 @@ import java.util.Collection;
 class CryptoWarningHandler {
 
 	private final Collection<String> resourcesWithInvalidMac;
+	private final Collection<String> whitelistedResources;
 
-	public CryptoWarningHandler(Collection<String> resourcesWithInvalidMac) {
+	public CryptoWarningHandler(Collection<String> resourcesWithInvalidMac, Collection<String> whitelistedResources) {
 		this.resourcesWithInvalidMac = resourcesWithInvalidMac;
+		this.whitelistedResources = whitelistedResources;
 	}
 
-	public void macAuthFailed(String resourceName) {
-		if (!resourcesWithInvalidMac.contains(resourceName)) {
-			resourcesWithInvalidMac.add(resourceName);
+	public void macAuthFailed(String resourcePath) {
+		// collection might be a list, but we don't want duplicates:
+		if (!resourcesWithInvalidMac.contains(resourcePath)) {
+			resourcesWithInvalidMac.add(resourcePath);
 		}
 	}
 
+	public boolean ignoreMac(String resourcePath) {
+		return whitelistedResources.contains(resourcePath);
+	}
+
 }

main/core/src/main/java/org/cryptomator/webdav/jackrabbit/EncryptedDir.java

@@ -12,7 +12,6 @@ import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.nio.ByteBuffer;
 import java.nio.channels.FileChannel;
-import java.nio.channels.FileLock;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.AtomicMoveNotSupportedException;
 import java.nio.file.DirectoryStream;
@@ -156,7 +155,8 @@ class EncryptedDir extends AbstractEncryptedNode implements FileConstants {
 			final String cleartextFilename = FilenameUtils.getName(childLocator.getResourcePath());
 			final String ciphertextFilename = filenameTranslator.getEncryptedFilename(cleartextFilename);
 			final Path filePath = dirPath.resolve(ciphertextFilename);
-			try (final FileChannel c = FileChannel.open(filePath, StandardOpenOption.WRITE, StandardOpenOption.CREATE, StandardOpenOption.TRUNCATE_EXISTING); final FileLock lock = c.lock(0L, FILE_HEADER_LENGTH, false)) {
+			try (final FileChannel c = FileChannel.open(filePath, StandardOpenOption.WRITE, StandardOpenOption.CREATE, StandardOpenOption.TRUNCATE_EXISTING);
+					final SilentlyFailingFileLock lock = new SilentlyFailingFileLock(c, 0L, FILE_HEADER_LENGTH, false)) {
 				cryptor.encryptFile(inputContext.getInputStream(), c);
 			} catch (SecurityException e) {
 				throw new DavException(DavServletResponse.SC_FORBIDDEN, e);
@@ -260,7 +260,7 @@ class EncryptedDir extends AbstractEncryptedNode implements FileConstants {
 		final Path srcPath = filePath;
 		final Path dstPath;
 		if (dest instanceof NonExistingNode) {
-			dstPath = ((NonExistingNode) dest).getDirFilePath();
+			dstPath = ((NonExistingNode) dest).materializeDirFilePath();
 		} else {
 			dstPath = dest.filePath;
 		}
@@ -278,7 +278,7 @@ class EncryptedDir extends AbstractEncryptedNode implements FileConstants {
 	public void copy(AbstractEncryptedNode dest, boolean shallow) throws DavException, IOException {
 		final Path dstDirFilePath;
 		if (dest instanceof NonExistingNode) {
-			dstDirFilePath = ((NonExistingNode) dest).getDirFilePath();
+			dstDirFilePath = ((NonExistingNode) dest).materializeDirFilePath();
 		} else {
 			dstDirFilePath = dest.filePath;
 		}
@@ -289,7 +289,8 @@ class EncryptedDir extends AbstractEncryptedNode implements FileConstants {
 			throw new DavException(DavServletResponse.SC_NOT_FOUND);
 		}
 		final String dstDirId = UUID.randomUUID().toString();
-		try (final FileChannel c = FileChannel.open(dstDirFilePath, StandardOpenOption.WRITE, StandardOpenOption.CREATE, StandardOpenOption.TRUNCATE_EXISTING, StandardOpenOption.DSYNC); final FileLock lock = c.lock()) {
+		try (final FileChannel c = FileChannel.open(dstDirFilePath, StandardOpenOption.WRITE, StandardOpenOption.CREATE, StandardOpenOption.TRUNCATE_EXISTING, StandardOpenOption.DSYNC);
+				SilentlyFailingFileLock lock = new SilentlyFailingFileLock(c, false)) {
 			c.write(ByteBuffer.wrap(dstDirId.getBytes(StandardCharsets.UTF_8)));
 		}
 

main/core/src/main/java/org/cryptomator/webdav/jackrabbit/EncryptedFile.java

@@ -11,9 +11,7 @@ package org.cryptomator.webdav.jackrabbit;
 import java.io.EOFException;
 import java.io.IOException;
 import java.nio.channels.FileChannel;
-import java.nio.channels.FileLock;
 import java.nio.channels.OverlappingFileLockException;
-import java.nio.channels.SeekableByteChannel;
 import java.nio.file.AtomicMoveNotSupportedException;
 import java.nio.file.Files;
 import java.nio.file.Path;
@@ -31,7 +29,6 @@ import org.apache.jackrabbit.webdav.lock.LockManager;
 import org.apache.jackrabbit.webdav.property.DavPropertyName;
 import org.apache.jackrabbit.webdav.property.DefaultDavProperty;
 import org.cryptomator.crypto.Cryptor;
-import org.cryptomator.crypto.exceptions.DecryptFailedException;
 import org.cryptomator.crypto.exceptions.MacAuthenticationFailedException;
 import org.cryptomator.webdav.exceptions.IORuntimeException;
 import org.eclipse.jetty.http.HttpHeader;
@@ -44,6 +41,7 @@ class EncryptedFile extends AbstractEncryptedNode implements FileConstants {
 	private static final Logger LOG = LoggerFactory.getLogger(EncryptedFile.class);
 
 	protected final CryptoWarningHandler cryptoWarningHandler;
+	protected final Long contentLength;
 
 	public EncryptedFile(CryptoResourceFactory factory, DavResourceLocator locator, DavSession session, LockManager lockManager, Cryptor cryptor, CryptoWarningHandler cryptoWarningHandler, Path filePath) {
 		super(factory, locator, session, lockManager, cryptor, filePath);
@@ -51,9 +49,10 @@ class EncryptedFile extends AbstractEncryptedNode implements FileConstants {
 			throw new IllegalArgumentException("filePath must not be null");
 		}
 		this.cryptoWarningHandler = cryptoWarningHandler;
+		Long contentLength = null;
 		if (Files.isRegularFile(filePath)) {
-			try (final FileChannel c = FileChannel.open(filePath, StandardOpenOption.READ, StandardOpenOption.DSYNC); final FileLock lock = c.tryLock(0L, FILE_HEADER_LENGTH, true)) {
-				final Long contentLength = cryptor.decryptedContentLength(c);
+			try (final FileChannel c = FileChannel.open(filePath, StandardOpenOption.READ, StandardOpenOption.DSYNC); SilentlyFailingFileLock lock = new SilentlyFailingFileLock(c, true)) {
+				contentLength = cryptor.decryptedContentLength(c);
 				properties.add(new DefaultDavProperty<Long>(DavPropertyName.GETCONTENTLENGTH, contentLength));
 				if (contentLength > RANGE_REQUEST_LOWER_LIMIT) {
 					properties.add(new HttpHeaderProperty(HttpHeader.ACCEPT_RANGES.asString(), HttpHeaderValue.BYTES.asString()));
@@ -61,14 +60,19 @@ class EncryptedFile extends AbstractEncryptedNode implements FileConstants {
 			} catch (OverlappingFileLockException e) {
 				// file header currently locked, report -1 for unknown size.
 				properties.add(new DefaultDavProperty<Long>(DavPropertyName.GETCONTENTLENGTH, -1l));
-			} catch (IOException e) {
-				LOG.error("Error reading filesize " + filePath.toString(), e);
-				throw new IORuntimeException(e);
 			} catch (MacAuthenticationFailedException e) {
 				LOG.warn("Content length couldn't be determined due to MAC authentication violation.");
 				// don't add content length DAV property
+			} catch (IOException e) {
+				LOG.error("Error reading filesize " + filePath.toString(), e);
+				throw new IORuntimeException(e);
 			}
 		}
+		this.contentLength = contentLength;
+	}
+
+	public Long getContentLength() {
+		return contentLength;
 	}
 
 	@Override
@@ -96,20 +100,17 @@ class EncryptedFile extends AbstractEncryptedNode implements FileConstants {
 		if (Files.isRegularFile(filePath)) {
 			outputContext.setModificationTime(Files.getLastModifiedTime(filePath).toMillis());
 			outputContext.setProperty(HttpHeader.ACCEPT_RANGES.asString(), HttpHeaderValue.BYTES.asString());
-			try (final SeekableByteChannel channel = Files.newByteChannel(filePath, StandardOpenOption.READ)) {
-				final Long contentLength = cryptor.decryptedContentLength(channel);
+			try (final FileChannel c = FileChannel.open(filePath, StandardOpenOption.READ); SilentlyFailingFileLock lock = new SilentlyFailingFileLock(c, true)) {
+				final Long contentLength = cryptor.decryptedContentLength(c);
 				if (contentLength != null) {
 					outputContext.setContentLength(contentLength);
 				}
 				if (outputContext.hasStream()) {
-					cryptor.decryptFile(channel, outputContext.getOutputStream());
+					final boolean authenticate = !cryptoWarningHandler.ignoreMac(getLocator().getResourcePath());
+					cryptor.decryptFile(c, outputContext.getOutputStream(), authenticate);
 				}
 			} catch (EOFException e) {
 				LOG.warn("Unexpected end of stream (possibly client hung up).");
-			} catch (MacAuthenticationFailedException e) {
-				cryptoWarningHandler.macAuthFailed(getLocator().getResourcePath());
-			} catch (DecryptFailedException e) {
-				throw new IOException("Error decrypting file " + filePath.toString(), e);
 			}
 		}
 	}
@@ -119,7 +120,7 @@ class EncryptedFile extends AbstractEncryptedNode implements FileConstants {
 		final Path srcPath = filePath;
 		final Path dstPath;
 		if (dest instanceof NonExistingNode) {
-			dstPath = ((NonExistingNode) dest).getFilePath();
+			dstPath = ((NonExistingNode) dest).materializeFilePath();
 		} else {
 			dstPath = dest.filePath;
 		}
@@ -136,7 +137,7 @@ class EncryptedFile extends AbstractEncryptedNode implements FileConstants {
 		final Path srcPath = filePath;
 		final Path dstPath;
 		if (dest instanceof NonExistingNode) {
-			dstPath = ((NonExistingNode) dest).getFilePath();
+			dstPath = ((NonExistingNode) dest).materializeFilePath();
 		} else {
 			dstPath = dest.filePath;
 		}

main/core/src/main/java/org/cryptomator/webdav/jackrabbit/EncryptedFilePart.java

@@ -2,34 +2,22 @@ package org.cryptomator.webdav.jackrabbit;
 
 import java.io.EOFException;
 import java.io.IOException;
-import java.nio.channels.ClosedByInterruptException;
-import java.nio.channels.SeekableByteChannel;
+import java.nio.channels.FileChannel;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.StandardOpenOption;
-import java.util.HashSet;
-import java.util.Set;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.TimeUnit;
 
-import org.apache.commons.lang3.StringUtils;
 import org.apache.commons.lang3.tuple.ImmutablePair;
-import org.apache.commons.lang3.tuple.MutablePair;
 import org.apache.commons.lang3.tuple.Pair;
 import org.apache.jackrabbit.webdav.DavResourceLocator;
-import org.apache.jackrabbit.webdav.DavServletRequest;
 import org.apache.jackrabbit.webdav.DavSession;
 import org.apache.jackrabbit.webdav.io.OutputContext;
 import org.apache.jackrabbit.webdav.lock.LockManager;
 import org.cryptomator.crypto.Cryptor;
-import org.cryptomator.crypto.exceptions.DecryptFailedException;
 import org.eclipse.jetty.http.HttpHeader;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import com.google.common.cache.Cache;
-import com.google.common.cache.CacheBuilder;
-
 /**
  * Delivers only the requested range of bytes from a file.
  * 
@@ -38,157 +26,60 @@ import com.google.common.cache.CacheBuilder;
 class EncryptedFilePart extends EncryptedFile {
 
 	private static final Logger LOG = LoggerFactory.getLogger(EncryptedFilePart.class);
-	private static final String BYTE_UNIT_PREFIX = "bytes=";
-	private static final char RANGE_SET_SEP = ',';
-	private static final char RANGE_SEP = '-';
-	private static final Cache<DavResourceLocator, MacAuthenticationJob> cachedMacAuthenticationJobs = CacheBuilder.newBuilder().expireAfterWrite(10, TimeUnit.MINUTES).build();
 
-	/**
-	 * e.g. range -500 (gets the last 500 bytes) -> (-1, 500)
-	 */
-	private static final Long SUFFIX_BYTE_RANGE_LOWER = -1L;
+	private final Pair<Long, Long> range;
 
-	/**
-	 * e.g. range 500- (gets all bytes from 500) -> (500, MAX_LONG)
-	 */
-	private static final Long SUFFIX_BYTE_RANGE_UPPER = Long.MAX_VALUE;
-
-	private final Set<Pair<Long, Long>> requestedContentRanges = new HashSet<Pair<Long, Long>>();
-
-	public EncryptedFilePart(CryptoResourceFactory factory, DavResourceLocator locator, DavSession session, DavServletRequest request, LockManager lockManager, Cryptor cryptor, CryptoWarningHandler cryptoWarningHandler,
-			ExecutorService backgroundTaskExecutor, Path filePath) {
+	public EncryptedFilePart(CryptoResourceFactory factory, DavResourceLocator locator, DavSession session, Pair<String, String> requestRange, LockManager lockManager, Cryptor cryptor,
+			CryptoWarningHandler cryptoWarningHandler, Path filePath) {
 		super(factory, locator, session, lockManager, cryptor, cryptoWarningHandler, filePath);
-		final String rangeHeader = request.getHeader(HttpHeader.RANGE.asString());
-		if (rangeHeader == null) {
-			throw new IllegalArgumentException("HTTP request doesn't contain a range header");
-		}
-		determineByteRanges(rangeHeader);
 
-		synchronized (cachedMacAuthenticationJobs) {
-			if (cachedMacAuthenticationJobs.getIfPresent(locator) == null) {
-				final MacAuthenticationJob macAuthJob = new MacAuthenticationJob(locator);
-				cachedMacAuthenticationJobs.put(locator, macAuthJob);
-				backgroundTaskExecutor.submit(macAuthJob);
-			}
-		}
-
-	}
-
-	private void determineByteRanges(String rangeHeader) {
-		final String byteRangeSet = StringUtils.removeStartIgnoreCase(rangeHeader, BYTE_UNIT_PREFIX);
-		final String[] byteRanges = StringUtils.split(byteRangeSet, RANGE_SET_SEP);
-		if (byteRanges.length == 0) {
-			throw new IllegalArgumentException("Invalid range: " + rangeHeader);
-		}
-		for (final String byteRange : byteRanges) {
-			final String[] bytePos = StringUtils.splitPreserveAllTokens(byteRange, RANGE_SEP);
-			if (bytePos.length != 2 || bytePos[0].isEmpty() && bytePos[1].isEmpty()) {
-				throw new IllegalArgumentException("Invalid range: " + rangeHeader);
-			}
-			final Long lower = bytePos[0].isEmpty() ? SUFFIX_BYTE_RANGE_LOWER : Long.valueOf(bytePos[0]);
-			final Long upper = bytePos[1].isEmpty() ? SUFFIX_BYTE_RANGE_UPPER : Long.valueOf(bytePos[1]);
-			if (lower > upper) {
-				throw new IllegalArgumentException("Invalid range: " + rangeHeader);
-			}
-			requestedContentRanges.add(new ImmutablePair<Long, Long>(lower, upper));
-		}
-	}
-
-	/**
-	 * @return One range, that spans all requested ranges.
-	 */
-	private Pair<Long, Long> getUnionRange(Long fileSize) {
-		final long lastByte = fileSize - 1;
-		final MutablePair<Long, Long> result = new MutablePair<Long, Long>();
-		for (Pair<Long, Long> range : requestedContentRanges) {
-			final long left;
-			final long right;
-			if (SUFFIX_BYTE_RANGE_LOWER.equals(range.getLeft())) {
-				left = lastByte - range.getRight();
-				right = lastByte;
-			} else if (SUFFIX_BYTE_RANGE_UPPER.equals(range.getRight())) {
-				left = range.getLeft();
-				right = lastByte;
+		try {
+			final Long lower = requestRange.getLeft().isEmpty() ? null : Long.valueOf(requestRange.getLeft());
+			final Long upper = requestRange.getRight().isEmpty() ? null : Long.valueOf(requestRange.getRight());
+			if (lower == null) {
+				range = new ImmutablePair<Long, Long>(contentLength - upper, contentLength - 1);
+			} else if (upper == null) {
+				range = new ImmutablePair<Long, Long>(lower, contentLength - 1);
 			} else {
-				left = range.getLeft();
-				right = range.getRight();
-			}
-			if (result.getLeft() == null || left < result.getLeft()) {
-				result.setLeft(left);
-			}
-			if (result.getRight() == null || right > result.getRight()) {
-				result.setRight(right);
+				range = new ImmutablePair<Long, Long>(lower, upper);
 			}
+		} catch (NumberFormatException e) {
+			throw new IllegalArgumentException("Invalid byte range: " + requestRange, e);
 		}
-		return result;
 	}
 
 	@Override
 	public void spool(OutputContext outputContext) throws IOException {
 		assert Files.isRegularFile(filePath);
+		assert this.contentLength != null;
+
+		final Long rangeLength = range.getRight() - range.getLeft() + 1;
 		outputContext.setModificationTime(Files.getLastModifiedTime(filePath).toMillis());
-		try (final SeekableByteChannel channel = Files.newByteChannel(filePath, StandardOpenOption.READ)) {
-			final Long fileSize = cryptor.decryptedContentLength(channel);
-			final Pair<Long, Long> range = getUnionRange(fileSize);
-			final Long rangeLength = range.getRight() - range.getLeft() + 1;
+		if (rangeLength <= 0) {
+			// unsatisfiable content range:
+			outputContext.setContentLength(0);
+			outputContext.setProperty(HttpHeader.CONTENT_RANGE.asString(), getContentRangeHeader(range.getRight(), range.getRight(), contentLength));
+			LOG.debug("Unsatisfiable content range: " + getContentRangeHeader(range.getLeft(), range.getRight(), contentLength));
+			return;
+		} else {
 			outputContext.setContentLength(rangeLength);
-			outputContext.setProperty(HttpHeader.CONTENT_RANGE.asString(), getContentRangeHeader(range.getLeft(), range.getRight(), fileSize));
+			outputContext.setProperty(HttpHeader.CONTENT_RANGE.asString(), getContentRangeHeader(range.getLeft(), range.getRight(), contentLength));
+		}
+
+		try (final FileChannel c = FileChannel.open(filePath, StandardOpenOption.READ)) {
 			if (outputContext.hasStream()) {
-				cryptor.decryptRange(channel, outputContext.getOutputStream(), range.getLeft(), rangeLength);
+				final boolean authenticate = !cryptoWarningHandler.ignoreMac(getLocator().getResourcePath());
+				cryptor.decryptRange(c, outputContext.getOutputStream(), range.getLeft(), rangeLength, authenticate);
 			}
 		} catch (EOFException e) {
 			if (LOG.isDebugEnabled()) {
 				LOG.trace("Unexpected end of stream during delivery of partial content (client hung up).");
 			}
-		} catch (DecryptFailedException e) {
-			throw new IOException("Error decrypting file " + filePath.toString(), e);
 		}
 	}
 
 	private String getContentRangeHeader(long firstByte, long lastByte, long completeLength) {
-		return String.format("%d-%d/%d", firstByte, lastByte, completeLength);
-	}
-
-	private class MacAuthenticationJob implements Runnable {
-
-		private final DavResourceLocator locator;
-
-		public MacAuthenticationJob(final DavResourceLocator locator) {
-			if (locator == null) {
-				throw new IllegalArgumentException("locator must not be null.");
-			}
-			this.locator = locator;
-		}
-
-		@Override
-		public void run() {
-			assert Files.isRegularFile(filePath);
-			try (final SeekableByteChannel channel = Files.newByteChannel(filePath, StandardOpenOption.READ)) {
-				final boolean authentic = cryptor.isAuthentic(channel);
-				if (!authentic) {
-					cryptoWarningHandler.macAuthFailed(locator.getResourcePath());
-				}
-			} catch (ClosedByInterruptException ex) {
-				LOG.debug("Couldn't finish MAC verification due to interruption of worker thread.");
-			} catch (IOException e) {
-				LOG.error("IOException during MAC verification of " + filePath.toString(), e);
-			}
-		}
-
-		@Override
-		public int hashCode() {
-			return locator.hashCode();
-		}
-
-		@Override
-		public boolean equals(Object obj) {
-			if (obj instanceof MacAuthenticationJob) {
-				final MacAuthenticationJob other = (MacAuthenticationJob) obj;
-				return this.locator.equals(other.locator);
-			} else {
-				return false;
-			}
-		}
+		return String.format("bytes %d-%d/%d", firstByte, lastByte, completeLength);
 	}
 
 }

main/core/src/main/java/org/cryptomator/webdav/jackrabbit/FileConstants.java

@@ -21,7 +21,7 @@ interface FileConstants {
 	/**
 	 * Number of bytes in the file header.
 	 */
-	long FILE_HEADER_LENGTH = 96;
+	long FILE_HEADER_LENGTH = 104;
 
 	/**
 	 * Allow range requests for files > 32MiB.

main/core/src/main/java/org/cryptomator/webdav/jackrabbit/FilenameTranslator.java

@@ -5,7 +5,6 @@ import java.io.IOException;
 import java.io.Serializable;
 import java.nio.ByteBuffer;
 import java.nio.channels.FileChannel;
-import java.nio.channels.FileLock;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.FileSystems;
 import java.nio.file.Files;
@@ -130,13 +129,14 @@ class FilenameTranslator implements FileConstants {
 	/* Locked I/O */
 
 	private void writeAllBytesAtomically(Path path, byte[] bytes) throws IOException {
-		try (final FileChannel c = FileChannel.open(path, StandardOpenOption.WRITE, StandardOpenOption.CREATE, StandardOpenOption.TRUNCATE_EXISTING, StandardOpenOption.DSYNC); final FileLock lock = c.lock()) {
+		try (final FileChannel c = FileChannel.open(path, StandardOpenOption.WRITE, StandardOpenOption.CREATE, StandardOpenOption.TRUNCATE_EXISTING, StandardOpenOption.DSYNC);
+				final SilentlyFailingFileLock lock = new SilentlyFailingFileLock(c, false)) {
 			c.write(ByteBuffer.wrap(bytes));
 		}
 	}
 
 	private byte[] readAllBytesAtomically(Path path) throws IOException {
-		try (final FileChannel c = FileChannel.open(path, StandardOpenOption.READ, StandardOpenOption.DSYNC); final FileLock lock = c.lock(0L, Long.MAX_VALUE, true)) {
+		try (final FileChannel c = FileChannel.open(path, StandardOpenOption.READ, StandardOpenOption.DSYNC); final SilentlyFailingFileLock lock = new SilentlyFailingFileLock(c, true)) {
 			final ByteBuffer buffer = ByteBuffer.allocate((int) c.size());
 			c.read(buffer);
 			return buffer.array();

main/core/src/main/java/org/cryptomator/webdav/jackrabbit/NonExistingNode.java

@@ -21,16 +21,12 @@ import org.apache.jackrabbit.webdav.io.OutputContext;
 import org.apache.jackrabbit.webdav.lock.LockManager;
 import org.apache.jackrabbit.webdav.property.DavProperty;
 import org.cryptomator.crypto.Cryptor;
+import org.cryptomator.webdav.jackrabbit.CryptoResourceFactory.NonExistingParentException;
 
 class NonExistingNode extends AbstractEncryptedNode {
 
-	private final Path filePath;
-	private final Path dirFilePath;
-
-	public NonExistingNode(CryptoResourceFactory factory, DavResourceLocator locator, DavSession session, LockManager lockManager, Cryptor cryptor, Path filePath, Path dirFilePath) {
+	public NonExistingNode(CryptoResourceFactory factory, DavResourceLocator locator, DavSession session, LockManager lockManager, Cryptor cryptor) {
 		super(factory, locator, session, lockManager, cryptor, null);
-		this.filePath = filePath;
-		this.dirFilePath = dirFilePath;
 	}
 
 	@Override
@@ -83,12 +79,26 @@ class NonExistingNode extends AbstractEncryptedNode {
 		throw new UnsupportedOperationException("Resource doesn't exist.");
 	}
 
-	public Path getFilePath() {
-		return filePath;
+	/**
+	 * @return lazily resolved file path, e.g. needed during MOVE operations.
+	 */
+	public Path materializeFilePath() {
+		try {
+			return factory.getEncryptedFilePath(locator.getResourcePath(), true);
+		} catch (NonExistingParentException e) {
+			throw new IllegalStateException(e);
+		}
 	}
 
-	public Path getDirFilePath() {
-		return dirFilePath;
+	/**
+	 * @return lazily resolved directory file path, e.g. needed during MOVE operations.
+	 */
+	public Path materializeDirFilePath() {
+		try {
+			return factory.getEncryptedDirectoryFilePath(locator.getResourcePath(), true);
+		} catch (NonExistingParentException e) {
+			throw new IllegalStateException(e);
+		}
 	}
 
 }

main/core/src/main/java/org/cryptomator/webdav/jackrabbit/SilentlyFailingFileLock.java

@@ -0,0 +1,56 @@
+package org.cryptomator.webdav.jackrabbit;
+
+import java.io.IOException;
+import java.nio.channels.FileChannel;
+import java.nio.channels.FileLock;
+import java.nio.channels.NonReadableChannelException;
+import java.nio.channels.NonWritableChannelException;
+import java.nio.channels.OverlappingFileLockException;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Instances of this class wrap a file lock, that is created upon construction and destroyed by {@link #close()}.
+ * 
+ * If the construction fails (e.g. if the file system does not support locks) no exception will be thrown and no lock is created.
+ */
+class SilentlyFailingFileLock implements AutoCloseable {
+
+	private static final Logger LOG = LoggerFactory.getLogger(SilentlyFailingFileLock.class);
+
+	private final FileLock lock;
+
+	/**
+	 * Invokes #SilentlyFailingFileLock(FileChannel, long, long, boolean) with a position of 0 and a size of {@link Long#MAX_VALUE}.
+	 */
+	SilentlyFailingFileLock(FileChannel channel, boolean shared) {
+		this(channel, 0L, Long.MAX_VALUE, shared);
+	}
+
+	/**
+	 * @throws NonReadableChannelException If shared is true this channel was not opened for reading
+	 * @throws NonWritableChannelException If shared is false but this channel was not opened for writing
+	 * @see FileChannel#lock(long, long, boolean)
+	 */
+	SilentlyFailingFileLock(FileChannel channel, long position, long size, boolean shared) {
+		FileLock lock = null;
+		try {
+			lock = channel.tryLock(position, size, shared);
+		} catch (IOException | OverlappingFileLockException e) {
+			if (LOG.isDebugEnabled()) {
+				LOG.warn("Unable to lock file.");
+			}
+		} finally {
+			this.lock = lock;
+		}
+	}
+
+	@Override
+	public void close() throws IOException {
+		if (lock != null) {
+			lock.close();
+		}
+	}
+
+}

main/core/src/main/java/org/cryptomator/webdav/jackrabbit/WebDavServlet.java

@@ -8,63 +8,50 @@
  ******************************************************************************/
 package org.cryptomator.webdav.jackrabbit;
 
+import java.io.IOException;
 import java.util.Collection;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.Executors;
-import java.util.concurrent.TimeUnit;
 
 import javax.servlet.ServletConfig;
 import javax.servlet.ServletException;
+import javax.servlet.http.HttpServletResponse;
 
+import org.apache.jackrabbit.webdav.DavException;
 import org.apache.jackrabbit.webdav.DavLocatorFactory;
 import org.apache.jackrabbit.webdav.DavResource;
 import org.apache.jackrabbit.webdav.DavResourceFactory;
 import org.apache.jackrabbit.webdav.DavSessionProvider;
 import org.apache.jackrabbit.webdav.WebdavRequest;
+import org.apache.jackrabbit.webdav.WebdavResponse;
 import org.apache.jackrabbit.webdav.server.AbstractWebdavServlet;
 import org.cryptomator.crypto.Cryptor;
+import org.cryptomator.crypto.exceptions.MacAuthenticationFailedException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 public class WebDavServlet extends AbstractWebdavServlet {
 
 	private static final long serialVersionUID = 7965170007048673022L;
+	private static final Logger LOG = LoggerFactory.getLogger(WebDavServlet.class);
 	public static final String CFG_FS_ROOT = "cfg.fs.root";
 	private DavSessionProvider davSessionProvider;
 	private DavLocatorFactory davLocatorFactory;
 	private DavResourceFactory davResourceFactory;
 	private final Cryptor cryptor;
 	private final CryptoWarningHandler cryptoWarningHandler;
-	private ExecutorService backgroundTaskExecutor;
 
-	public WebDavServlet(final Cryptor cryptor, final Collection<String> failingMacCollection) {
+	public WebDavServlet(final Cryptor cryptor, final Collection<String> failingMacCollection, final Collection<String> whitelistedResourceCollection) {
 		super();
 		this.cryptor = cryptor;
-		this.cryptoWarningHandler = new CryptoWarningHandler(failingMacCollection);
+		this.cryptoWarningHandler = new CryptoWarningHandler(failingMacCollection, whitelistedResourceCollection);
 	}
 
 	@Override
 	public void init(ServletConfig config) throws ServletException {
 		super.init(config);
 		final String fsRoot = config.getInitParameter(CFG_FS_ROOT);
-		backgroundTaskExecutor = Executors.newCachedThreadPool();
 		davSessionProvider = new DavSessionProviderImpl();
 		davLocatorFactory = new CleartextLocatorFactory(config.getServletContext().getContextPath());
-		davResourceFactory = new CryptoResourceFactory(cryptor, cryptoWarningHandler, backgroundTaskExecutor, fsRoot);
-	}
-
-	@Override
-	public void destroy() {
-		backgroundTaskExecutor.shutdown();
-		try {
-			final boolean tasksFinished = backgroundTaskExecutor.awaitTermination(2, TimeUnit.SECONDS);
-			if (!tasksFinished) {
-				backgroundTaskExecutor.shutdownNow();
-			}
-		} catch (InterruptedException e) {
-			backgroundTaskExecutor.shutdownNow();
-			Thread.currentThread().interrupt();
-		} finally {
-			super.destroy();
-		}
+		davResourceFactory = new CryptoResourceFactory(cryptor, cryptoWarningHandler, fsRoot);
 	}
 
 	@Override
@@ -102,4 +89,30 @@ public class WebDavServlet extends AbstractWebdavServlet {
 		this.davResourceFactory = resourceFactory;
 	}
 
+	@Override
+	protected void doPut(WebdavRequest request, WebdavResponse response, DavResource resource) throws IOException, DavException {
+		long t0 = System.nanoTime();
+		super.doPut(request, response, resource);
+		if (LOG.isDebugEnabled()) {
+			long t1 = System.nanoTime();
+			LOG.debug("PUT TIME: " + (t1 - t0) / 1000 / 1000.0 + " ms");
+		}
+	}
+
+	@Override
+	protected void doGet(WebdavRequest request, WebdavResponse response, DavResource resource) throws IOException, DavException {
+		long t0 = System.nanoTime();
+		try {
+			super.doGet(request, response, resource);
+		} catch (MacAuthenticationFailedException e) {
+			LOG.warn("File integrity violation for " + resource.getLocator().getResourcePath());
+			cryptoWarningHandler.macAuthFailed(resource.getLocator().getResourcePath());
+			response.sendError(HttpServletResponse.SC_SERVICE_UNAVAILABLE);
+		}
+		if (LOG.isDebugEnabled()) {
+			long t1 = System.nanoTime();
+			LOG.debug("GET TIME: " + (t1 - t0) / 1000 / 1000.0 + " ms");
+		}
+	}
+
 }

main/core/src/test/java/org/cryptomator/webdav/jackrabbit/RangeRequestTest.java

@@ -0,0 +1,271 @@
+package org.cryptomator.webdav.jackrabbit;
+
+import java.io.ByteArrayInputStream;
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.URI;
+import java.net.URISyntaxException;
+import java.net.URL;
+import java.nio.ByteBuffer;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+import java.util.Random;
+import java.util.concurrent.ForkJoinPool;
+import java.util.concurrent.ForkJoinTask;
+import java.util.concurrent.atomic.AtomicBoolean;
+
+import org.apache.commons.httpclient.HttpClient;
+import org.apache.commons.httpclient.HttpMethod;
+import org.apache.commons.httpclient.MultiThreadedHttpConnectionManager;
+import org.apache.commons.httpclient.methods.ByteArrayRequestEntity;
+import org.apache.commons.httpclient.methods.EntityEnclosingMethod;
+import org.apache.commons.httpclient.methods.GetMethod;
+import org.apache.commons.httpclient.methods.PutMethod;
+import org.apache.commons.io.FileUtils;
+import org.apache.commons.io.IOUtils;
+import org.cryptomator.crypto.aes256.Aes256Cryptor;
+import org.cryptomator.webdav.WebDavServer;
+import org.cryptomator.webdav.WebDavServer.ServletLifeCycleAdapter;
+import org.junit.AfterClass;
+import org.junit.Assert;
+import org.junit.BeforeClass;
+import org.junit.Test;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.google.common.io.Files;
+
+public class RangeRequestTest {
+
+	private static final Logger LOG = LoggerFactory.getLogger(RangeRequestTest.class);
+	private static final Aes256Cryptor CRYPTOR = new Aes256Cryptor();
+	private static final WebDavServer SERVER = new WebDavServer();
+	private static final File TMP_VAULT = Files.createTempDir();
+	private static ServletLifeCycleAdapter SERVLET;
+	private static URI VAULT_BASE_URI;
+
+	@BeforeClass
+	public static void startServer() throws URISyntaxException {
+		SERVER.start();
+		SERVLET = SERVER.createServlet(TMP_VAULT.toPath(), CRYPTOR, new ArrayList<String>(), new ArrayList<String>(), "JUnitTestVault");
+		SERVLET.start();
+		VAULT_BASE_URI = new URI("http", SERVLET.getServletUri().getSchemeSpecificPart() + "/", null);
+		Assert.assertTrue(SERVLET.isRunning());
+		Assert.assertNotNull(VAULT_BASE_URI);
+	}
+
+	@AfterClass
+	public static void stopServer() {
+		SERVLET.stop();
+		SERVER.stop();
+		FileUtils.deleteQuietly(TMP_VAULT);
+	}
+
+	@Test
+	public void testFullFileDecryption() throws IOException, URISyntaxException {
+		final URL testResourceUrl = new URL(VAULT_BASE_URI.toURL(), "fullFileDecryptionTestFile.txt");
+		final HttpClient client = new HttpClient();
+
+		// prepare 64MiB test data:
+		final byte[] plaintextData = new byte[16777216 * Integer.BYTES];
+		final ByteBuffer bbIn = ByteBuffer.wrap(plaintextData);
+		for (int i = 0; i < 16777216; i++) {
+			bbIn.putInt(i);
+		}
+		final InputStream plaintextDataInputStream = new ByteArrayInputStream(plaintextData);
+
+		// put request:
+		final EntityEnclosingMethod putMethod = new PutMethod(testResourceUrl.toString());
+		putMethod.setRequestEntity(new ByteArrayRequestEntity(plaintextData));
+		final int putResponse = client.executeMethod(putMethod);
+		putMethod.releaseConnection();
+		Assert.assertEquals(201, putResponse);
+
+		// get request:
+		final HttpMethod getMethod = new GetMethod(testResourceUrl.toString());
+		final int statusCode = client.executeMethod(getMethod);
+		Assert.assertEquals(200, statusCode);
+		// final byte[] received = new byte[plaintextData.length];
+		// IOUtils.read(getMethod.getResponseBodyAsStream(), received);
+		// Assert.assertArrayEquals(plaintextData, received);
+		Assert.assertTrue(IOUtils.contentEquals(plaintextDataInputStream, getMethod.getResponseBodyAsStream()));
+		getMethod.releaseConnection();
+	}
+
+	@Test
+	public void testAsyncRangeRequests() throws IOException, URISyntaxException, InterruptedException {
+		final URL testResourceUrl = new URL(VAULT_BASE_URI.toURL(), "asyncRangeRequestTestFile.txt");
+
+		final MultiThreadedHttpConnectionManager cm = new MultiThreadedHttpConnectionManager();
+		cm.getParams().setDefaultMaxConnectionsPerHost(50);
+		final HttpClient client = new HttpClient(cm);
+
+		// prepare 8MiB test data:
+		final byte[] plaintextData = new byte[2097152 * Integer.BYTES];
+		final ByteBuffer bbIn = ByteBuffer.wrap(plaintextData);
+		for (int i = 0; i < 2097152; i++) {
+			bbIn.putInt(i);
+		}
+
+		// put request:
+		final EntityEnclosingMethod putMethod = new PutMethod(testResourceUrl.toString());
+		putMethod.setRequestEntity(new ByteArrayRequestEntity(plaintextData));
+		final int putResponse = client.executeMethod(putMethod);
+		putMethod.releaseConnection();
+		Assert.assertEquals(201, putResponse);
+
+		// multiple async range requests:
+		final List<ForkJoinTask<?>> tasks = new ArrayList<>();
+		final Random generator = new Random(System.currentTimeMillis());
+
+		final AtomicBoolean success = new AtomicBoolean(true);
+
+		// 10 full interrupted requests:
+		for (int i = 0; i < 10; i++) {
+			final ForkJoinTask<?> task = ForkJoinTask.adapt(() -> {
+				try {
+					final HttpMethod getMethod = new GetMethod(testResourceUrl.toString());
+					final int statusCode = client.executeMethod(getMethod);
+					if (statusCode != 200) {
+						LOG.error("Invalid status code for interrupted full request");
+						success.set(false);
+					}
+					getMethod.getResponseBodyAsStream().read();
+					getMethod.getResponseBodyAsStream().close();
+					getMethod.releaseConnection();
+				} catch (IOException e) {
+					throw new RuntimeException(e);
+				}
+			});
+			tasks.add(task);
+		}
+
+		// 50 crappy interrupted range requests:
+		for (int i = 0; i < 50; i++) {
+			final int lower = generator.nextInt(plaintextData.length);
+			final ForkJoinTask<?> task = ForkJoinTask.adapt(() -> {
+				try {
+					final HttpMethod getMethod = new GetMethod(testResourceUrl.toString());
+					getMethod.addRequestHeader("Range", "bytes=" + lower + "-");
+					final int statusCode = client.executeMethod(getMethod);
+					if (statusCode != 206) {
+						LOG.error("Invalid status code for interrupted range request");
+						success.set(false);
+					}
+					getMethod.getResponseBodyAsStream().read();
+					getMethod.getResponseBodyAsStream().close();
+					getMethod.releaseConnection();
+				} catch (IOException e) {
+					throw new RuntimeException(e);
+				}
+			});
+			tasks.add(task);
+		}
+
+		// 50 normal open range requests:
+		for (int i = 0; i < 50; i++) {
+			final int lower = generator.nextInt(plaintextData.length - 512);
+			final int upper = plaintextData.length - 1;
+			final ForkJoinTask<?> task = ForkJoinTask.adapt(() -> {
+				try {
+					final HttpMethod getMethod = new GetMethod(testResourceUrl.toString());
+					getMethod.addRequestHeader("Range", "bytes=" + lower + "-");
+					final byte[] expected = Arrays.copyOfRange(plaintextData, lower, upper + 1);
+					final int statusCode = client.executeMethod(getMethod);
+					final byte[] responseBody = new byte[upper - lower + 10];
+					final int bytesRead = IOUtils.read(getMethod.getResponseBodyAsStream(), responseBody);
+					getMethod.releaseConnection();
+					if (statusCode != 206) {
+						LOG.error("Invalid status code for open range request");
+						success.set(false);
+					} else if (upper - lower + 1 != bytesRead) {
+						LOG.error("Invalid response length for open range request");
+						success.set(false);
+					} else if (!Arrays.equals(expected, Arrays.copyOfRange(responseBody, 0, bytesRead))) {
+						LOG.error("Invalid response body for open range request");
+						success.set(false);
+					}
+				} catch (IOException e) {
+					throw new RuntimeException(e);
+				}
+			});
+			tasks.add(task);
+		}
+
+		// 200 normal closed range requests:
+		for (int i = 0; i < 200; i++) {
+			final int pos1 = generator.nextInt(plaintextData.length - 512);
+			final int pos2 = pos1 + 512;
+			final ForkJoinTask<?> task = ForkJoinTask.adapt(() -> {
+				try {
+					final int lower = Math.min(pos1, pos2);
+					final int upper = Math.max(pos1, pos2);
+					final HttpMethod getMethod = new GetMethod(testResourceUrl.toString());
+					getMethod.addRequestHeader("Range", "bytes=" + lower + "-" + upper);
+					final byte[] expected = Arrays.copyOfRange(plaintextData, lower, upper + 1);
+					final int statusCode = client.executeMethod(getMethod);
+					final byte[] responseBody = new byte[upper - lower + 1];
+					final int bytesRead = IOUtils.read(getMethod.getResponseBodyAsStream(), responseBody);
+					getMethod.releaseConnection();
+					if (statusCode != 206) {
+						LOG.error("Invalid status code for closed range request");
+						success.set(false);
+					} else if (upper - lower + 1 != bytesRead) {
+						LOG.error("Invalid response length for closed range request");
+						success.set(false);
+					} else if (!Arrays.equals(expected, Arrays.copyOfRange(responseBody, 0, bytesRead))) {
+						LOG.error("Invalid response body for closed range request");
+						success.set(false);
+					}
+				} catch (IOException e) {
+					throw new RuntimeException(e);
+				}
+			});
+			tasks.add(task);
+		}
+
+		Collections.shuffle(tasks, generator);
+
+		final ForkJoinPool pool = new ForkJoinPool(4);
+		for (ForkJoinTask<?> task : tasks) {
+			pool.execute(task);
+		}
+		for (ForkJoinTask<?> task : tasks) {
+			task.join();
+		}
+		pool.shutdown();
+		cm.shutdown();
+
+		Assert.assertTrue(success.get());
+	}
+
+	@Test
+	public void testUnsatisfiableRangeRequest() throws IOException, URISyntaxException {
+		final URL testResourceUrl = new URL(VAULT_BASE_URI.toURL(), "unsatisfiableRangeRequestTestFile.txt");
+		final HttpClient client = new HttpClient();
+
+		// prepare file content:
+		final byte[] fileContent = "This is some test file content.".getBytes();
+
+		// put request:
+		final EntityEnclosingMethod putMethod = new PutMethod(testResourceUrl.toString());
+		putMethod.setRequestEntity(new ByteArrayRequestEntity(fileContent));
+		final int putResponse = client.executeMethod(putMethod);
+		putMethod.releaseConnection();
+		Assert.assertEquals(201, putResponse);
+
+		// get request:
+		final HttpMethod getMethod = new GetMethod(testResourceUrl.toString());
+		getMethod.addRequestHeader("Range", "chunks=1-2");
+		final int getResponse = client.executeMethod(getMethod);
+		final byte[] response = new byte[fileContent.length];
+		IOUtils.read(getMethod.getResponseBodyAsStream(), response);
+		getMethod.releaseConnection();
+		Assert.assertEquals(416, getResponse);
+		Assert.assertArrayEquals(fileContent, response);
+	}
+
+}

main/core/src/test/resources/log4j2.xml

@@ -0,0 +1,33 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<!--
+  Copyright (c) 2014 Markus Kreusch
+  This file is licensed under the terms of the MIT license.
+  See the LICENSE.txt file for more info.
+  
+  Contributors:
+      Sebastian Stenzel - log4j config for WebDAV unit tests
+-->
+<Configuration status="WARN">
+
+	<Appenders>
+		<Console name="Console" target="SYSTEM_OUT">
+			<PatternLayout pattern="%16d %-5p [%c{1}:%L] %m%n" />
+			<ThresholdFilter level="WARN" onMatch="DENY" onMismatch="ACCEPT" />
+		</Console>
+		<Console name="StdErr" target="SYSTEM_ERR">
+			<PatternLayout pattern="%16d %-5p [%c{1}:%L] %m%n" />
+			<ThresholdFilter level="WARN" onMatch="ACCEPT" onMismatch="DENY" />
+		</Console>
+	</Appenders>
+
+	<Loggers>
+		<!-- show our own debug messages: -->
+		<Logger name="org.cryptomator" level="DEBUG" />
+		<!-- mute dependencies: -->
+		<Root level="INFO">
+			<AppenderRef ref="Console" />
+			<AppenderRef ref="StdErr" />
+		</Root>
+	</Loggers>
+
+</Configuration>

main/crypto-aes/pom.xml

@@ -12,7 +12,7 @@
 	<parent>
 		<groupId>org.cryptomator</groupId>
 		<artifactId>main</artifactId>
-		<version>0.7.0</version>
+		<version>0.8.2</version>
 	</parent>
 	<artifactId>crypto-aes</artifactId>
 	<name>Cryptomator cryptographic module (AES)</name>

main/crypto-aes/src/main/java/org/cryptomator/crypto/aes256/Aes256Cryptor.java

@@ -8,11 +8,12 @@
  ******************************************************************************/
 package org.cryptomator.crypto.aes256;
 
-import java.io.BufferedOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
 import java.nio.ByteBuffer;
+import java.nio.channels.Channels;
+import java.nio.channels.ReadableByteChannel;
 import java.nio.channels.SeekableByteChannel;
 import java.nio.charset.StandardCharsets;
 import java.security.InvalidAlgorithmParameterException;
@@ -21,26 +22,24 @@ import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
 import java.security.SecureRandom;
 import java.util.Arrays;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.TimeUnit;
 
 import javax.crypto.BadPaddingException;
 import javax.crypto.Cipher;
-import javax.crypto.CipherInputStream;
-import javax.crypto.CipherOutputStream;
 import javax.crypto.IllegalBlockSizeException;
 import javax.crypto.Mac;
 import javax.crypto.NoSuchPaddingException;
 import javax.crypto.SecretKey;
+import javax.crypto.ShortBufferException;
 import javax.crypto.spec.IvParameterSpec;
 import javax.crypto.spec.SecretKeySpec;
 import javax.security.auth.DestroyFailedException;
 import javax.security.auth.Destroyable;
 
 import org.apache.commons.io.IOUtils;
-import org.apache.commons.io.output.NullOutputStream;
 import org.bouncycastle.crypto.generators.SCrypt;
 import org.cryptomator.crypto.Cryptor;
-import org.cryptomator.crypto.aes256.CounterAwareInputStream.CounterAwareInputLimitReachedException;
-import org.cryptomator.crypto.exceptions.CounterOverflowException;
 import org.cryptomator.crypto.exceptions.DecryptFailedException;
 import org.cryptomator.crypto.exceptions.EncryptFailedException;
 import org.cryptomator.crypto.exceptions.MacAuthenticationFailedException;
@@ -48,12 +47,15 @@ import org.cryptomator.crypto.exceptions.UnsupportedKeyLengthException;
 import org.cryptomator.crypto.exceptions.UnsupportedVaultException;
 import org.cryptomator.crypto.exceptions.WrongPasswordException;
 import org.cryptomator.crypto.io.SeekableByteChannelInputStream;
-import org.cryptomator.crypto.io.SeekableByteChannelOutputStream;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import com.fasterxml.jackson.databind.ObjectMapper;
 
 public class Aes256Cryptor implements Cryptor, AesCryptographicConfiguration {
 
+	private static final Logger LOG = LoggerFactory.getLogger(Aes256Cryptor.class);
+
 	/**
 	 * Defined in static initializer. Defaults to 256, but falls back to maximum value possible, if JCE Unlimited Strength Jurisdiction Policy Files isn't installed. Those files can be downloaded
 	 * here: http://www.oracle.com/technetwork/java/javase/downloads/.
@@ -211,7 +213,7 @@ public class Aes256Cryptor implements Cryptor, AesCryptographicConfiguration {
 		} catch (InvalidKeyException ex) {
 			throw new IllegalArgumentException("Invalid key.", ex);
 		} catch (NoSuchAlgorithmException | NoSuchPaddingException ex) {
-			throw new IllegalStateException("Algorithm/Padding should exist and accept GCM specs.", ex);
+			throw new IllegalStateException("Algorithm/Padding should exist.", ex);
 		}
 	}
 
@@ -308,7 +310,7 @@ public class Aes256Cryptor implements Cryptor, AesCryptographicConfiguration {
 	public Long decryptedContentLength(SeekableByteChannel encryptedFile) throws IOException, MacAuthenticationFailedException {
 		// read header:
 		encryptedFile.position(0);
-		final ByteBuffer headerBuf = ByteBuffer.allocate(64);
+		final ByteBuffer headerBuf = ByteBuffer.allocate(104);
 		final int headerBytesRead = encryptedFile.read(headerBuf);
 		if (headerBytesRead != headerBuf.capacity()) {
 			return null;
@@ -319,20 +321,20 @@ public class Aes256Cryptor implements Cryptor, AesCryptographicConfiguration {
 		headerBuf.position(0);
 		headerBuf.get(iv);
 
-		// read content length:
-		final byte[] encryptedContentLengthBytes = new byte[AES_BLOCK_LENGTH];
-		headerBuf.position(16);
-		headerBuf.get(encryptedContentLengthBytes);
+		// read sensitive header data:
+		final byte[] encryptedSensitiveHeaderContentBytes = new byte[48];
+		headerBuf.position(24);
+		headerBuf.get(encryptedSensitiveHeaderContentBytes);
 
 		// read stored header mac:
 		final byte[] storedHeaderMac = new byte[32];
-		headerBuf.position(32);
+		headerBuf.position(72);
 		headerBuf.get(storedHeaderMac);
 
-		// calculate mac over first 32 bytes of header:
+		// calculate mac over first 72 bytes of header:
 		final Mac headerMac = this.hmacSha256(hMacMasterKey);
 		headerBuf.rewind();
-		headerBuf.limit(32);
+		headerBuf.limit(72);
 		headerMac.update(headerBuf);
 
 		final boolean macMatches = MessageDigest.isEqual(storedHeaderMac, headerMac.doFinal());
@@ -340,75 +342,37 @@ public class Aes256Cryptor implements Cryptor, AesCryptographicConfiguration {
 			throw new MacAuthenticationFailedException("MAC authentication failed.");
 		}
 
-		return decryptContentLength(encryptedContentLengthBytes, iv);
+		// decrypt sensitive header data:
+		final byte[] decryptedSensitiveHeaderContentBytes = decryptHeaderData(encryptedSensitiveHeaderContentBytes, iv);
+		final ByteBuffer sensitiveHeaderContentBuf = ByteBuffer.wrap(decryptedSensitiveHeaderContentBytes);
+		final Long fileSize = sensitiveHeaderContentBuf.getLong();
+
+		return fileSize;
 	}
 
-	private long decryptContentLength(byte[] encryptedContentLengthBytes, byte[] iv) {
+	private byte[] decryptHeaderData(byte[] ciphertextBytes, byte[] iv) {
 		try {
 			final Cipher sizeCipher = aesCbcCipher(primaryMasterKey, iv, Cipher.DECRYPT_MODE);
-			final byte[] decryptedFileSize = sizeCipher.doFinal(encryptedContentLengthBytes);
-			final ByteBuffer fileSizeBuffer = ByteBuffer.wrap(decryptedFileSize);
-			return fileSizeBuffer.getLong();
+			return sizeCipher.doFinal(ciphertextBytes);
 		} catch (IllegalBlockSizeException | BadPaddingException e) {
 			throw new IllegalStateException(e);
 		}
 	}
 
-	private byte[] encryptContentLength(long contentLength, byte[] iv) {
+	private byte[] encryptHeaderData(byte[] plaintextBytes, byte[] iv) {
 		try {
-			final ByteBuffer fileSizeBuffer = ByteBuffer.allocate(Long.BYTES);
-			fileSizeBuffer.putLong(contentLength);
 			final Cipher sizeCipher = aesCbcCipher(primaryMasterKey, iv, Cipher.ENCRYPT_MODE);
-			return sizeCipher.doFinal(fileSizeBuffer.array());
+			return sizeCipher.doFinal(plaintextBytes);
 		} catch (IllegalBlockSizeException | BadPaddingException e) {
 			throw new IllegalStateException("Block size must be valid, as padding is requested. BadPaddingException not possible in encrypt mode.", e);
 		}
 	}
 
 	@Override
-	public boolean isAuthentic(SeekableByteChannel encryptedFile) throws IOException {
+	public Long decryptFile(SeekableByteChannel encryptedFile, OutputStream plaintextFile, boolean authenticate) throws IOException, DecryptFailedException {
 		// read header:
 		encryptedFile.position(0l);
-		final ByteBuffer headerBuf = ByteBuffer.allocate(96);
-		final int headerBytesRead = encryptedFile.read(headerBuf);
-		if (headerBytesRead != headerBuf.capacity()) {
-			throw new IOException("Failed to read file header.");
-		}
-
-		// read header mac:
-		final byte[] storedHeaderMac = new byte[32];
-		headerBuf.position(32);
-		headerBuf.get(storedHeaderMac);
-
-		// read content mac:
-		final byte[] storedContentMac = new byte[32];
-		headerBuf.position(64);
-		headerBuf.get(storedContentMac);
-
-		// calculate mac over first 32 bytes of header:
-		final Mac headerMac = this.hmacSha256(hMacMasterKey);
-		headerBuf.position(0);
-		headerBuf.limit(32);
-		headerMac.update(headerBuf);
-
-		// calculate mac over content:
-		encryptedFile.position(96l);
-		final Mac contentMac = this.hmacSha256(hMacMasterKey);
-		final InputStream in = new SeekableByteChannelInputStream(encryptedFile);
-		final InputStream macIn = new MacInputStream(in, contentMac);
-		IOUtils.copyLarge(macIn, new NullOutputStream());
-
-		// compare (in constant time):
-		final boolean headerMacMatches = MessageDigest.isEqual(storedHeaderMac, headerMac.doFinal());
-		final boolean contentMacMatches = MessageDigest.isEqual(storedContentMac, contentMac.doFinal());
-		return headerMacMatches && contentMacMatches;
-	}
-
-	@Override
-	public Long decryptFile(SeekableByteChannel encryptedFile, OutputStream plaintextFile) throws IOException, DecryptFailedException {
-		// read header:
-		encryptedFile.position(0l);
-		final ByteBuffer headerBuf = ByteBuffer.allocate(96);
+		final ByteBuffer headerBuf = ByteBuffer.allocate(104);
 		final int headerBytesRead = encryptedFile.read(headerBuf);
 		if (headerBytesRead != headerBuf.capacity()) {
 			throw new IOException("Failed to read file header.");
@@ -419,134 +383,348 @@ public class Aes256Cryptor implements Cryptor, AesCryptographicConfiguration {
 		headerBuf.position(0);
 		headerBuf.get(iv);
 
-		// read content length:
-		final byte[] encryptedContentLengthBytes = new byte[AES_BLOCK_LENGTH];
+		// read nonce:
+		final byte[] nonce = new byte[8];
 		headerBuf.position(16);
-		headerBuf.get(encryptedContentLengthBytes);
-		final Long fileSize = decryptContentLength(encryptedContentLengthBytes, iv);
+		headerBuf.get(nonce);
+
+		// read sensitive header data:
+		final byte[] encryptedSensitiveHeaderContentBytes = new byte[48];
+		headerBuf.position(24);
+		headerBuf.get(encryptedSensitiveHeaderContentBytes);
 
 		// read header mac:
-		final byte[] headerMac = new byte[32];
-		headerBuf.position(32);
-		headerBuf.get(headerMac);
+		final byte[] storedHeaderMac = new byte[32];
+		headerBuf.position(72);
+		headerBuf.get(storedHeaderMac);
 
-		// read content mac:
-		final byte[] contentMac = new byte[32];
-		headerBuf.position(64);
-		headerBuf.get(contentMac);
-
-		// decrypt content
-		encryptedFile.position(96l);
-		final Mac calculatedContentMac = this.hmacSha256(hMacMasterKey);
-		final Cipher cipher = this.aesCtrCipher(primaryMasterKey, iv, Cipher.DECRYPT_MODE);
-		final InputStream in = new SeekableByteChannelInputStream(encryptedFile);
-		final InputStream macIn = new MacInputStream(in, calculatedContentMac);
-		final InputStream cipheredIn = new CipherInputStream(macIn, cipher);
-		final long bytesDecrypted = IOUtils.copyLarge(cipheredIn, plaintextFile, 0, fileSize);
-
-		// drain remaining bytes to /dev/null to complete MAC calculation:
-		IOUtils.copyLarge(macIn, new NullOutputStream());
-
-		// compare (in constant time):
-		final boolean macMatches = MessageDigest.isEqual(contentMac, calculatedContentMac.doFinal());
-		if (!macMatches) {
-			// This exception will be thrown AFTER we sent the decrypted content to the user.
-			// This has two advantages:
-			// - we don't need to read files twice
-			// - we can still restore files suffering from non-malicious bit rotting
-			// Anyway me MUST make sure to warn the user. This will be done by the UI when catching this exception.
-			throw new MacAuthenticationFailedException("MAC authentication failed.");
+		// calculate mac over first 72 bytes of header:
+		if (authenticate) {
+			final Mac headerMac = this.hmacSha256(hMacMasterKey);
+			headerBuf.position(0);
+			headerBuf.limit(72);
+			headerMac.update(headerBuf);
+			if (!MessageDigest.isEqual(storedHeaderMac, headerMac.doFinal())) {
+				throw new MacAuthenticationFailedException("Header MAC authentication failed.");
+			}
 		}
 
-		return bytesDecrypted;
+		// decrypt sensitive header data:
+		final byte[] fileKeyBytes = new byte[32];
+		final byte[] decryptedSensitiveHeaderContentBytes = decryptHeaderData(encryptedSensitiveHeaderContentBytes, iv);
+		final ByteBuffer sensitiveHeaderContentBuf = ByteBuffer.wrap(decryptedSensitiveHeaderContentBytes);
+		final Long fileSize = sensitiveHeaderContentBuf.getLong();
+		sensitiveHeaderContentBuf.get(fileKeyBytes);
+
+		// prepare content decryption:
+		final SecretKey fileKey = new SecretKeySpec(fileKeyBytes, AES_KEY_ALGORITHM);
+		final LengthLimitingOutputStream paddingRemovingOutputStream = new LengthLimitingOutputStream(plaintextFile, fileSize);
+		final CryptoWorkerExecutor executor = new CryptoWorkerExecutor(Runtime.getRuntime().availableProcessors(), (lock, blockDone, currentBlock, inputQueue) -> {
+			return new DecryptWorker(lock, blockDone, currentBlock, inputQueue, authenticate, Channels.newChannel(paddingRemovingOutputStream)) {
+
+				@Override
+				protected Cipher initCipher(long startBlockNum) {
+					final ByteBuffer nonceAndCounterBuf = ByteBuffer.allocate(AES_BLOCK_LENGTH);
+					nonceAndCounterBuf.put(nonce);
+					nonceAndCounterBuf.putLong(startBlockNum * CONTENT_MAC_BLOCK / AES_BLOCK_LENGTH);
+					final byte[] nonceAndCounter = nonceAndCounterBuf.array();
+					return aesCtrCipher(fileKey, nonceAndCounter, Cipher.DECRYPT_MODE);
+				}
+
+				@Override
+				protected Mac initMac() {
+					return hmacSha256(hMacMasterKey);
+				}
+
+				@Override
+				protected void checkMac(Mac mac, long blockNum, ByteBuffer ciphertextBuf, ByteBuffer macBuf) throws MacAuthenticationFailedException {
+					mac.update(iv);
+					mac.update(longToByteArray(blockNum));
+					mac.update(ciphertextBuf);
+					final byte[] calculatedMac = mac.doFinal();
+					final byte[] storedMac = new byte[mac.getMacLength()];
+					macBuf.get(storedMac);
+					if (!MessageDigest.isEqual(calculatedMac, storedMac)) {
+						throw new MacAuthenticationFailedException("Content MAC authentication failed.");
+					}
+				}
+
+				@Override
+				protected void decrypt(Cipher cipher, ByteBuffer ciphertextBuf, ByteBuffer plaintextBuf) throws DecryptFailedException {
+					assert plaintextBuf.remaining() >= cipher.getOutputSize(ciphertextBuf.remaining());
+					try {
+						cipher.update(ciphertextBuf, plaintextBuf);
+					} catch (ShortBufferException e) {
+						throw new DecryptFailedException(e);
+					}
+				}
+
+			};
+		});
+
+		// read as many blocks from file as possible, but wait if queue is full:
+		encryptedFile.position(104l);
+		final int maxNumBlocks = 64;
+		int numBlocks = 1;
+		int bytesRead = 0;
+		long blockNumber = 0;
+		do {
+			if (numBlocks < maxNumBlocks) {
+				numBlocks++;
+			}
+			final int inBufSize = numBlocks * (CONTENT_MAC_BLOCK + 32);
+			final ByteBuffer buf = ByteBuffer.allocate(inBufSize);
+			bytesRead = encryptedFile.read(buf);
+			buf.flip();
+			final int blocksRead = (int) Math.ceil(bytesRead / (double) (CONTENT_MAC_BLOCK + 32));
+			final boolean consumedInTime = executor.offer(new BlocksData(buf.asReadOnlyBuffer(), blockNumber, blocksRead), 1, TimeUnit.SECONDS);
+			if (!consumedInTime) {
+				break;
+			}
+			blockNumber += numBlocks;
+		} while (bytesRead == numBlocks * (CONTENT_MAC_BLOCK + 32));
+
+		// wait for decryption workers to finish:
+		try {
+			executor.waitUntilDone();
+		} catch (ExecutionException e) {
+			final Throwable cause = e.getCause();
+			if (cause instanceof IOException) {
+				throw (IOException) cause;
+			} else if (cause instanceof RuntimeException) {
+				throw (RuntimeException) cause;
+			} else {
+				LOG.error("Unexpected exception", e);
+			}
+		} finally {
+			destroyQuietly(fileKey);
+		}
+
+		return paddingRemovingOutputStream.getBytesWritten();
 	}
 
 	@Override
-	public Long decryptRange(SeekableByteChannel encryptedFile, OutputStream plaintextFile, long pos, long length) throws IOException, DecryptFailedException {
-		// read iv:
+	public Long decryptRange(SeekableByteChannel encryptedFile, OutputStream plaintextFile, long pos, long length, boolean authenticate) throws IOException, DecryptFailedException {
+		// read header:
 		encryptedFile.position(0l);
-		final ByteBuffer countingIv = ByteBuffer.allocate(AES_BLOCK_LENGTH);
-		final int numIvBytesRead = encryptedFile.read(countingIv);
-
-		// check validity of header:
-		if (numIvBytesRead != AES_BLOCK_LENGTH) {
+		final ByteBuffer headerBuf = ByteBuffer.allocate(104);
+		final int headerBytesRead = encryptedFile.read(headerBuf);
+		if (headerBytesRead != headerBuf.capacity()) {
 			throw new IOException("Failed to read file header.");
 		}
 
-		// seek relevant position and update iv:
-		long firstRelevantBlock = pos / AES_BLOCK_LENGTH; // cut of fraction!
-		long beginOfFirstRelevantBlock = firstRelevantBlock * AES_BLOCK_LENGTH;
-		long offsetInsideFirstRelevantBlock = pos - beginOfFirstRelevantBlock;
-		countingIv.putInt(AES_BLOCK_LENGTH - Integer.BYTES, (int) firstRelevantBlock); // int-cast is possible, as max file size is 64GiB
+		// read iv:
+		final byte[] iv = new byte[AES_BLOCK_LENGTH];
+		headerBuf.position(0);
+		headerBuf.get(iv);
 
-		// fast forward stream:
-		encryptedFile.position(96l + beginOfFirstRelevantBlock);
+		// read nonce:
+		final byte[] nonce = new byte[8];
+		headerBuf.position(16);
+		headerBuf.get(nonce);
 
-		// generate cipher:
-		final Cipher cipher = this.aesCtrCipher(primaryMasterKey, countingIv.array(), Cipher.DECRYPT_MODE);
+		// read sensitive header data:
+		final byte[] encryptedSensitiveHeaderContentBytes = new byte[48];
+		headerBuf.position(24);
+		headerBuf.get(encryptedSensitiveHeaderContentBytes);
 
-		// read content
-		final InputStream in = new SeekableByteChannelInputStream(encryptedFile);
-		final InputStream cipheredIn = new CipherInputStream(in, cipher);
-		return IOUtils.copyLarge(cipheredIn, plaintextFile, offsetInsideFirstRelevantBlock, length);
+		// read header mac:
+		final byte[] storedHeaderMac = new byte[32];
+		headerBuf.position(72);
+		headerBuf.get(storedHeaderMac);
+
+		// calculate mac over first 72 bytes of header:
+		if (authenticate) {
+			final Mac headerMac = this.hmacSha256(hMacMasterKey);
+			headerBuf.position(0);
+			headerBuf.limit(72);
+			headerMac.update(headerBuf);
+			if (!MessageDigest.isEqual(storedHeaderMac, headerMac.doFinal())) {
+				throw new MacAuthenticationFailedException("Header MAC authentication failed.");
+			}
+		}
+
+		// decrypt sensitive header data:
+		final byte[] fileKeyBytes = new byte[32];
+		final byte[] decryptedSensitiveHeaderContentBytes = decryptHeaderData(encryptedSensitiveHeaderContentBytes, iv);
+		final ByteBuffer sensitiveHeaderContentBuf = ByteBuffer.wrap(decryptedSensitiveHeaderContentBytes);
+		sensitiveHeaderContentBuf.position(Long.BYTES); // skip file size
+		sensitiveHeaderContentBuf.get(fileKeyBytes);
+
+		// find first relevant block:
+		final long startBlock = pos / CONTENT_MAC_BLOCK; // floor
+		final long startByte = startBlock * (CONTENT_MAC_BLOCK + 32) + 104;
+		final long offsetFromFirstBlock = pos - startBlock * CONTENT_MAC_BLOCK;
+
+		// append correct counter value to nonce:
+		final ByteBuffer nonceAndCounterBuf = ByteBuffer.allocate(AES_BLOCK_LENGTH);
+		nonceAndCounterBuf.put(nonce);
+		nonceAndCounterBuf.putLong(startBlock * CONTENT_MAC_BLOCK / AES_BLOCK_LENGTH);
+		final byte[] nonceAndCounter = nonceAndCounterBuf.array();
+
+		// content decryption:
+		encryptedFile.position(startByte);
+		final SecretKey fileKey = new SecretKeySpec(fileKeyBytes, AES_KEY_ALGORITHM);
+		final Cipher cipher = this.aesCtrCipher(fileKey, nonceAndCounter, Cipher.DECRYPT_MODE);
+		final Mac contentMac = this.hmacSha256(hMacMasterKey);
+
+		try {
+			// reading ciphered input and MACs interleaved:
+			long bytesWritten = 0;
+			final InputStream in = new SeekableByteChannelInputStream(encryptedFile);
+			byte[] buffer = new byte[CONTENT_MAC_BLOCK + 32];
+			int n = 0;
+			long blockNum = startBlock;
+			while ((n = IOUtils.read(in, buffer)) > 0 && bytesWritten < length) {
+				if (n < 32) {
+					throw new DecryptFailedException("Invalid file content, missing MAC.");
+				}
+
+				// check MAC of current block:
+				if (authenticate) {
+					contentMac.update(iv);
+					contentMac.update(longToByteArray(blockNum));
+					contentMac.update(buffer, 0, n - 32);
+					final byte[] calculatedMac = contentMac.doFinal();
+					final byte[] storedMac = new byte[32];
+					System.arraycopy(buffer, n - 32, storedMac, 0, 32);
+					if (!MessageDigest.isEqual(calculatedMac, storedMac)) {
+						throw new MacAuthenticationFailedException("Content MAC authentication failed.");
+					}
+				}
+
+				// decrypt block:
+				final byte[] plaintext = cipher.update(buffer, 0, n - 32);
+				final int offset = (bytesWritten == 0) ? (int) offsetFromFirstBlock : 0;
+				final long pending = length - bytesWritten;
+				final int available = plaintext.length - offset;
+				final int currentBatch = (int) Math.min(pending, available);
+
+				plaintextFile.write(plaintext, offset, currentBatch);
+				bytesWritten += currentBatch;
+				blockNum++;
+			}
+			return bytesWritten;
+		} finally {
+			destroyQuietly(fileKey);
+		}
 	}
 
 	/**
-	 * header = {16 byte iv, 16 byte filesize, 32 byte headerMac, 32 byte contentMac}
+	 * header = {16 byte iv, 8 byte nonce, 48 byte sensitive header data (file size + file key + padding), 32 byte headerMac}
 	 */
 	@Override
 	public Long encryptFile(InputStream plaintextFile, SeekableByteChannel encryptedFile) throws IOException, EncryptFailedException {
 		// truncate file
 		encryptedFile.truncate(0l);
 
-		// use an IV, whose last 8 bytes store a long used in counter mode and write initial value to file.
-		final ByteBuffer ivBuf = ByteBuffer.wrap(randomData(AES_BLOCK_LENGTH));
-		ivBuf.putInt(AES_BLOCK_LENGTH - Integer.BYTES, 0);
-		final byte[] iv = ivBuf.array();
+		// choose a random header IV:
+		final byte[] iv = randomData(AES_BLOCK_LENGTH);
 
-		// 96 byte header buffer (16 IV, 16 size, 32 headerMac, 32 contentMac), filled after writing the content
-		final ByteBuffer headerBuf = ByteBuffer.allocate(96);
-		headerBuf.limit(96);
+		// chosse 8 byte random nonce and 8 byte counter set to zero:
+		final byte[] nonce = randomData(8);
+
+		// choose a random content key:
+		final byte[] fileKeyBytes = randomData(32);
+
+		// 104 byte header buffer (16 header IV, 8 content nonce, 48 sensitive header data, 32 headerMac), filled after writing the content
+		final ByteBuffer headerBuf = ByteBuffer.allocate(104);
+		headerBuf.limit(104);
 		encryptedFile.write(headerBuf);
 
-		// content encryption:
-		final Cipher cipher = this.aesCtrCipher(primaryMasterKey, iv, Cipher.ENCRYPT_MODE);
-		final Mac contentMac = this.hmacSha256(hMacMasterKey);
-		final OutputStream out = new SeekableByteChannelOutputStream(encryptedFile);
-		final OutputStream macOut = new MacOutputStream(out, contentMac);
-		final OutputStream cipheredOut = new CipherOutputStream(macOut, cipher);
-		final OutputStream blockSizeBufferedOut = new BufferedOutputStream(cipheredOut, AES_BLOCK_LENGTH);
-		final InputStream lengthLimitingIn = new CounterAwareInputStream(plaintextFile);
-		final Long plaintextSize;
-		try {
-			plaintextSize = IOUtils.copyLarge(lengthLimitingIn, blockSizeBufferedOut);
-		} catch (CounterAwareInputLimitReachedException ex) {
-			encryptedFile.truncate(0l);
-			throw new CounterOverflowException("File size exceeds limit (64Gib). Aborting to prevent counter overflow.");
-		}
+		// prepare content encryption:
+		final SecretKey fileKey = new SecretKeySpec(fileKeyBytes, AES_KEY_ALGORITHM);
+		final CryptoWorkerExecutor executor = new CryptoWorkerExecutor(Runtime.getRuntime().availableProcessors(), (lock, blockDone, currentBlock, inputQueue) -> {
+			return new EncryptWorker(lock, blockDone, currentBlock, inputQueue, encryptedFile) {
 
-		// add random length padding to obfuscate file length:
-		final long numberOfPlaintextBlocks = (int) Math.ceil(plaintextSize / AES_BLOCK_LENGTH);
-		final long minAdditionalBlocks = 4;
-		final long maxAdditionalBlocks = Math.min(numberOfPlaintextBlocks >> 3, 1024 * 1024); // 12,5% of original blocks, but not more than 1M blocks (16MiBs)
-		final long availableBlocks = (1l << 32) - numberOfPlaintextBlocks; // before reaching limit of 2^32 blocks
-		final long additionalBlocks = (long) Math.min(Math.random() * Math.max(minAdditionalBlocks, maxAdditionalBlocks), availableBlocks);
+				@Override
+				protected Cipher initCipher(long startBlockNum) {
+					final ByteBuffer nonceAndCounterBuf = ByteBuffer.allocate(AES_BLOCK_LENGTH);
+					nonceAndCounterBuf.put(nonce);
+					nonceAndCounterBuf.putLong(startBlockNum * CONTENT_MAC_BLOCK / AES_BLOCK_LENGTH);
+					final byte[] nonceAndCounter = nonceAndCounterBuf.array();
+					return aesCtrCipher(fileKey, nonceAndCounter, Cipher.ENCRYPT_MODE);
+				}
+
+				@Override
+				protected Mac initMac() {
+					return hmacSha256(hMacMasterKey);
+				}
+
+				@Override
+				protected byte[] calcMac(Mac mac, long blockNum, ByteBuffer ciphertextBuf) {
+					mac.update(iv);
+					mac.update(longToByteArray(blockNum));
+					mac.update(ciphertextBuf);
+					return mac.doFinal();
+				}
+
+				@Override
+				protected void encrypt(Cipher cipher, ByteBuffer plaintextBuf, ByteBuffer ciphertextBuf) throws EncryptFailedException {
+					try {
+						assert ciphertextBuf.remaining() >= cipher.getOutputSize(plaintextBuf.remaining());
+						cipher.update(plaintextBuf, ciphertextBuf);
+					} catch (ShortBufferException e) {
+						throw new EncryptFailedException(e);
+					}
+				}
+			};
+		});
+
+		// read as many blocks from file as possible, but wait if queue is full:
 		final byte[] randomPadding = this.randomData(AES_BLOCK_LENGTH);
-		for (int i = 0; i < additionalBlocks; i += AES_BLOCK_LENGTH) {
-			blockSizeBufferedOut.write(randomPadding);
+		final LengthObfuscatingInputStream in = new LengthObfuscatingInputStream(plaintextFile, randomPadding);
+		final ReadableByteChannel channel = Channels.newChannel(in);
+		int bytesRead = 0;
+		long blockNumber = 0;
+		final int maxNumBlocks = 64;
+		int numBlocks = 0;
+		do {
+			if (numBlocks < maxNumBlocks) {
+				numBlocks++;
+			}
+			final int inBufSize = numBlocks * CONTENT_MAC_BLOCK;
+			final ByteBuffer inBuf = ByteBuffer.allocate(inBufSize);
+			bytesRead = channel.read(inBuf);
+			inBuf.flip();
+			final int blocksRead = (int) Math.ceil(bytesRead / (double) CONTENT_MAC_BLOCK);
+			final boolean consumedInTime = executor.offer(new BlocksData(inBuf.asReadOnlyBuffer(), blockNumber, blocksRead), 1, TimeUnit.SECONDS);
+			if (!consumedInTime) {
+				break;
+			}
+			blockNumber += numBlocks;
+		} while (bytesRead == numBlocks * CONTENT_MAC_BLOCK);
+
+		// wait for encryption workers to finish:
+		try {
+			executor.waitUntilDone();
+		} catch (ExecutionException e) {
+			final Throwable cause = e.getCause();
+			if (cause instanceof IOException) {
+				throw (IOException) cause;
+			} else if (cause instanceof RuntimeException) {
+				throw (RuntimeException) cause;
+			} else {
+				LOG.error("Unexpected exception", e);
+			}
+		} finally {
+			destroyQuietly(fileKey);
 		}
-		blockSizeBufferedOut.flush();
 
 		// create and write header:
+		final long plaintextSize = in.getRealInputLength();
+		final ByteBuffer sensitiveHeaderContentBuf = ByteBuffer.allocate(Long.BYTES + fileKeyBytes.length);
+		sensitiveHeaderContentBuf.putLong(plaintextSize);
+		sensitiveHeaderContentBuf.put(fileKeyBytes);
 		headerBuf.clear();
 		headerBuf.put(iv);
-		headerBuf.put(encryptContentLength(plaintextSize, iv));
+		headerBuf.put(nonce);
+		headerBuf.put(encryptHeaderData(sensitiveHeaderContentBuf.array(), iv));
 		headerBuf.flip();
 		final Mac headerMac = this.hmacSha256(hMacMasterKey);
 		headerMac.update(headerBuf);
-		headerBuf.limit(96);
+		headerBuf.limit(104);
 		headerBuf.put(headerMac.doFinal());
-		headerBuf.put(contentMac.doFinal());
 		headerBuf.flip();
 		encryptedFile.position(0);
 		encryptedFile.write(headerBuf);
@@ -554,4 +732,8 @@ public class Aes256Cryptor implements Cryptor, AesCryptographicConfiguration {
 		return plaintextSize;
 	}
 
+	private byte[] longToByteArray(long lng) {
+		return ByteBuffer.allocate(Long.SIZE / Byte.SIZE).putLong(lng).array();
+	}
+
 }

main/crypto-aes/src/main/java/org/cryptomator/crypto/aes256/AesCryptographicConfiguration.java

@@ -81,6 +81,11 @@ interface AesCryptographicConfiguration {
 	 */
 	int AES_BLOCK_LENGTH = 16;
 
+	/**
+	 * Number of bytes, a content block over which a MAC is calculated consists of.
+	 */
+	int CONTENT_MAC_BLOCK = 32 * 1024;
+
 	/**
 	 * How to encode the encrypted file names safely. Base32 uses only alphanumeric characters and is case-insensitive.
 	 */

main/crypto-aes/src/main/java/org/cryptomator/crypto/aes256/BlocksData.java

@@ -0,0 +1,22 @@
+package org.cryptomator.crypto.aes256;
+
+import java.nio.ByteBuffer;
+
+class BlocksData {
+
+	public static final int MAX_NUM_BLOCKS = 128;
+
+	final ByteBuffer buffer;
+	final long startBlockNum;
+	final int numBlocks;
+
+	BlocksData(ByteBuffer buffer, long startBlockNum, int numBlocks) {
+		if (numBlocks > MAX_NUM_BLOCKS) {
+			throw new IllegalArgumentException("Too many blocks to process at once: " + numBlocks);
+		}
+		this.buffer = buffer;
+		this.startBlockNum = startBlockNum;
+		this.numBlocks = numBlocks;
+	}
+
+}

main/crypto-aes/src/main/java/org/cryptomator/crypto/aes256/CounterAwareInputStream.java

@@ -1,57 +0,0 @@
-package org.cryptomator.crypto.aes256;
-
-import java.io.FilterInputStream;
-import java.io.IOException;
-import java.io.InputStream;
-import java.util.concurrent.atomic.AtomicLong;
-
-/**
- * Throws an exception, if more than (2^32)-1 16 byte blocks will be encrypted (would result in an counter overflow).<br/>
- * From https://tools.ietf.org/html/rfc3686: <cite> Using the encryption process described in section 2.1, this construction permits each packet to consist of up to: (2^32)-1 blocks</cite>
- */
-class CounterAwareInputStream extends FilterInputStream {
-
-	static final long SIXTY_FOUR_GIGABYE = ((1l << 32) - 1) * 16;
-
-	private final AtomicLong counter;
-
-	/**
-	 * @param in Stream from which to read contents, which will update the Mac.
-	 */
-	public CounterAwareInputStream(InputStream in) {
-		super(in);
-		this.counter = new AtomicLong(0l);
-	}
-
-	@Override
-	public int read() throws IOException {
-		int b = in.read();
-		if (b != -1) {
-			final long currentValue = counter.incrementAndGet();
-			failWhen64GibReached(currentValue);
-		}
-		return b;
-	}
-
-	@Override
-	public int read(byte[] b, int off, int len) throws IOException {
-		int read = in.read(b, off, len);
-		if (read > 0) {
-			final long currentValue = counter.addAndGet(read);
-			failWhen64GibReached(currentValue);
-		}
-		return read;
-	}
-
-	private void failWhen64GibReached(long currentValue) throws CounterAwareInputLimitReachedException {
-		if (currentValue > SIXTY_FOUR_GIGABYE) {
-			throw new CounterAwareInputLimitReachedException();
-		}
-	}
-
-	static class CounterAwareInputLimitReachedException extends IOException {
-		private static final long serialVersionUID = -1905012809288019359L;
-
-	}
-
-}

main/crypto-aes/src/main/java/org/cryptomator/crypto/aes256/CryptoWorker.java

@@ -0,0 +1,64 @@
+package org.cryptomator.crypto.aes256;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.Callable;
+import java.util.concurrent.atomic.AtomicLong;
+import java.util.concurrent.locks.Condition;
+import java.util.concurrent.locks.Lock;
+
+import org.cryptomator.crypto.exceptions.CryptingException;
+
+abstract class CryptoWorker implements Callable<Void> {
+
+	static final BlocksData POISON = new BlocksData(ByteBuffer.allocate(0), -1L, 0);
+
+	final Lock lock;
+	final Condition blockDone;
+	final AtomicLong currentBlock;
+	final BlockingQueue<BlocksData> queue;
+
+	public CryptoWorker(Lock lock, Condition blockDone, AtomicLong currentBlock, BlockingQueue<BlocksData> queue) {
+		this.lock = lock;
+		this.blockDone = blockDone;
+		this.currentBlock = currentBlock;
+		this.queue = queue;
+	}
+
+	@Override
+	public final Void call() throws IOException {
+		try {
+			while (!Thread.currentThread().isInterrupted()) {
+				final BlocksData blocksData = queue.take();
+				if (blocksData == POISON) {
+					// put poison back in for other threads:
+					break;
+				}
+				final ByteBuffer processedBytes = this.process(blocksData);
+				lock.lock();
+				try {
+					while (currentBlock.get() != blocksData.startBlockNum) {
+						blockDone.await();
+					}
+					assert currentBlock.get() == blocksData.startBlockNum;
+					// yay, its my turn!
+					this.write(processedBytes);
+					// signal worker working on next block:
+					currentBlock.set(blocksData.startBlockNum + blocksData.numBlocks);
+					blockDone.signalAll();
+				} finally {
+					lock.unlock();
+				}
+			}
+		} catch (InterruptedException e) {
+			Thread.currentThread().interrupt();
+		}
+		return null;
+	}
+
+	protected abstract ByteBuffer process(BlocksData block) throws CryptingException;
+
+	protected abstract void write(ByteBuffer processedBytes) throws IOException;
+
+}

main/crypto-aes/src/main/java/org/cryptomator/crypto/aes256/CryptoWorkerExecutor.java

@@ -0,0 +1,112 @@
+package org.cryptomator.crypto.aes256;
+
+import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.CompletionService;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.ExecutorCompletionService;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.LinkedBlockingQueue;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicLong;
+import java.util.concurrent.locks.Condition;
+import java.util.concurrent.locks.Lock;
+import java.util.concurrent.locks.ReentrantLock;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+class CryptoWorkerExecutor {
+
+	private static final Logger LOG = LoggerFactory.getLogger(CryptoWorkerExecutor.class);
+
+	private final int numWorkers;
+	private final Lock lock;
+	private final Condition blockDone;
+	private final AtomicLong currentBlock;
+	private final BlockingQueue<BlocksData> inputQueue;
+	private final ExecutorService executorService;
+	private final CompletionService<Void> completionService;
+	private boolean acceptWork;
+
+	/**
+	 * Starts as many {@link CryptoWorker} as specified in the constructor, that start working immediately on the items submitted via {@link #offer(BlocksData, long, TimeUnit)}.
+	 */
+	public CryptoWorkerExecutor(int numWorkers, WorkerFactory workerFactory) {
+		this.numWorkers = numWorkers;
+		this.lock = new ReentrantLock();
+		this.blockDone = lock.newCondition();
+		this.currentBlock = new AtomicLong();
+		this.inputQueue = new LinkedBlockingQueue<>(numWorkers * 2); // one cycle read-ahead
+		this.executorService = Executors.newFixedThreadPool(numWorkers);
+		this.completionService = new ExecutorCompletionService<>(executorService);
+		this.acceptWork = true;
+
+		// start workers:
+		for (int i = 0; i < numWorkers; i++) {
+			final CryptoWorker worker = workerFactory.createWorker(lock, blockDone, currentBlock, inputQueue);
+			completionService.submit(worker);
+		}
+	}
+
+	/**
+	 * Adds work to the work queue. On timeout all workers will be shut down.
+	 * 
+	 * @see BlockingQueue#offer(Object, long, TimeUnit)
+	 * @return <code>true</code> if the work has been added in time. <code>false</code> in any other case.
+	 */
+	public boolean offer(BlocksData data, long timeout, TimeUnit unit) {
+		if (!acceptWork) {
+			return false;
+		}
+		try {
+			final boolean success = inputQueue.offer(data, timeout, unit);
+			if (!success) {
+				this.acceptWork = false;
+				inputQueue.clear();
+				poisonWorkers();
+			}
+			return success;
+		} catch (InterruptedException e) {
+			LOG.error("Interrupted thread.", e);
+			executorService.shutdownNow();
+			Thread.currentThread().interrupt();
+		}
+		return false;
+	}
+
+	/**
+	 * Graceful shutdown of this executor, waiting for all jobs to finish (normally or by throwing exceptions).
+	 * 
+	 * @throws ExecutionException If any of the workers failed.
+	 */
+	public void waitUntilDone() throws ExecutionException {
+		this.acceptWork = false;
+		try {
+			poisonWorkers();
+			// now workers will one after another finish their work, potentially throwing an ExecutionException:
+			for (int i = 0; i < numWorkers; i++) {
+				completionService.take().get();
+			}
+		} catch (InterruptedException e) {
+			LOG.error("Interrupted thread.", e);
+			Thread.currentThread().interrupt();
+		} finally {
+			// shutdown either after normal decryption or if ANY worker threw an exception:
+			executorService.shutdownNow();
+		}
+	}
+
+	private void poisonWorkers() throws InterruptedException {
+		// add enough poison for each worker:
+		for (int i = 0; i < numWorkers; i++) {
+			inputQueue.put(CryptoWorker.POISON);
+		}
+	}
+
+	@FunctionalInterface
+	interface WorkerFactory {
+		CryptoWorker createWorker(Lock lock, Condition blockDone, AtomicLong currentBlock, BlockingQueue<BlocksData> inputQueue);
+	}
+
+}

main/crypto-aes/src/main/java/org/cryptomator/crypto/aes256/DecryptWorker.java

@@ -0,0 +1,75 @@
+package org.cryptomator.crypto.aes256;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.nio.channels.WritableByteChannel;
+import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.atomic.AtomicLong;
+import java.util.concurrent.locks.Condition;
+import java.util.concurrent.locks.Lock;
+
+import javax.crypto.Cipher;
+import javax.crypto.Mac;
+
+import org.cryptomator.crypto.exceptions.CryptingException;
+import org.cryptomator.crypto.exceptions.DecryptFailedException;
+import org.cryptomator.crypto.exceptions.MacAuthenticationFailedException;
+
+abstract class DecryptWorker extends CryptoWorker implements AesCryptographicConfiguration {
+
+	private final boolean shouldAuthenticate;
+	private final WritableByteChannel out;
+
+	public DecryptWorker(Lock lock, Condition blockDone, AtomicLong currentBlock, BlockingQueue<BlocksData> queue, boolean shouldAuthenticate, WritableByteChannel out) {
+		super(lock, blockDone, currentBlock, queue);
+		this.shouldAuthenticate = shouldAuthenticate;
+		this.out = out;
+	}
+
+	@Override
+	protected ByteBuffer process(BlocksData data) throws CryptingException {
+		final Cipher cipher = initCipher(data.startBlockNum);
+		final Mac mac = initMac();
+
+		final ByteBuffer plaintextBuf = ByteBuffer.allocate(cipher.getOutputSize(CONTENT_MAC_BLOCK) * data.numBlocks);
+
+		final ByteBuffer ciphertextBuf = data.buffer.asReadOnlyBuffer();
+		final ByteBuffer macBuf = data.buffer.asReadOnlyBuffer();
+
+		for (long blockNum = data.startBlockNum; blockNum < data.startBlockNum + data.numBlocks; blockNum++) {
+			assert (blockNum - data.startBlockNum) < BlocksData.MAX_NUM_BLOCKS;
+			assert (blockNum - data.startBlockNum) * CONTENT_MAC_BLOCK < Integer.MAX_VALUE;
+			final int pos = (int) (blockNum - data.startBlockNum) * (CONTENT_MAC_BLOCK + mac.getMacLength());
+			ciphertextBuf.limit(Math.min(data.buffer.limit() - mac.getMacLength(), pos + CONTENT_MAC_BLOCK));
+			ciphertextBuf.position(pos);
+			try {
+				macBuf.limit(ciphertextBuf.limit() + mac.getMacLength());
+				macBuf.position(ciphertextBuf.limit());
+			} catch (IllegalArgumentException e) {
+				throw new DecryptFailedException("Invalid file content, missing MAC.");
+			}
+			if (shouldAuthenticate) {
+				checkMac(mac, blockNum, ciphertextBuf, macBuf);
+			}
+			ciphertextBuf.position(pos);
+			decrypt(cipher, ciphertextBuf, plaintextBuf);
+		}
+
+		plaintextBuf.flip();
+		return plaintextBuf;
+	}
+
+	@Override
+	protected void write(ByteBuffer processedBytes) throws IOException {
+		out.write(processedBytes);
+	}
+
+	protected abstract Cipher initCipher(long startBlockNum);
+
+	protected abstract Mac initMac();
+
+	protected abstract void checkMac(Mac mac, long blockNum, ByteBuffer ciphertextBuf, ByteBuffer macBuf) throws MacAuthenticationFailedException;
+
+	protected abstract void decrypt(Cipher cipher, ByteBuffer ciphertextBuf, ByteBuffer plaintextBuf) throws DecryptFailedException;
+
+}

main/crypto-aes/src/main/java/org/cryptomator/crypto/aes256/EncryptWorker.java

@@ -0,0 +1,61 @@
+package org.cryptomator.crypto.aes256;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.nio.channels.WritableByteChannel;
+import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.atomic.AtomicLong;
+import java.util.concurrent.locks.Condition;
+import java.util.concurrent.locks.Lock;
+
+import javax.crypto.Cipher;
+import javax.crypto.Mac;
+
+import org.cryptomator.crypto.exceptions.CryptingException;
+import org.cryptomator.crypto.exceptions.EncryptFailedException;
+
+abstract class EncryptWorker extends CryptoWorker implements AesCryptographicConfiguration {
+
+	private final WritableByteChannel out;
+
+	public EncryptWorker(Lock lock, Condition blockDone, AtomicLong currentBlock, BlockingQueue<BlocksData> queue, WritableByteChannel out) {
+		super(lock, blockDone, currentBlock, queue);
+		this.out = out;
+	}
+
+	@Override
+	protected ByteBuffer process(BlocksData data) throws CryptingException {
+		final Cipher cipher = initCipher(data.startBlockNum);
+		final Mac mac = initMac();
+
+		final ByteBuffer ciphertextBuf = ByteBuffer.allocate((cipher.getOutputSize(CONTENT_MAC_BLOCK) + mac.getMacLength()) * data.numBlocks);
+		final ByteBuffer plaintextBuf = data.buffer.asReadOnlyBuffer();
+
+		for (long blockNum = data.startBlockNum; blockNum < data.startBlockNum + data.numBlocks; blockNum++) {
+			final int pos = (int) (blockNum - data.startBlockNum) * CONTENT_MAC_BLOCK;
+			plaintextBuf.limit(Math.min(data.buffer.limit(), pos + CONTENT_MAC_BLOCK));
+			encrypt(cipher, plaintextBuf, ciphertextBuf);
+			final ByteBuffer toMac = ciphertextBuf.asReadOnlyBuffer();
+			toMac.limit(ciphertextBuf.position());
+			toMac.position((int) (blockNum - data.startBlockNum) * (CONTENT_MAC_BLOCK + mac.getMacLength()));
+			ciphertextBuf.put(calcMac(mac, blockNum, toMac));
+		}
+
+		ciphertextBuf.flip();
+		return ciphertextBuf;
+	}
+
+	@Override
+	protected void write(ByteBuffer processedBytes) throws IOException {
+		out.write(processedBytes);
+	}
+
+	protected abstract Cipher initCipher(long startBlockNum);
+
+	protected abstract Mac initMac();
+
+	protected abstract byte[] calcMac(Mac mac, long blockNum, ByteBuffer ciphertextBuf);
+
+	protected abstract void encrypt(Cipher cipher, ByteBuffer plaintextBuf, ByteBuffer ciphertextBuf) throws EncryptFailedException;
+
+}

main/crypto-aes/src/main/java/org/cryptomator/crypto/aes256/KeyFile.java

@@ -7,7 +7,7 @@ import com.fasterxml.jackson.annotation.JsonPropertyOrder;
 @JsonPropertyOrder(value = {"version", "scryptSalt", "scryptCostParam", "scryptBlockSize", "keyLength", "primaryMasterKey", "hMacMasterKey"})
 public class KeyFile implements Serializable {
 
-	static final Integer CURRENT_VERSION = 1;
+	static final Integer CURRENT_VERSION = 2;
 	private static final long serialVersionUID = 8578363158959619885L;
 
 	private Integer version;

main/crypto-aes/src/main/java/org/cryptomator/crypto/aes256/LengthLimitingOutputStream.java

@@ -0,0 +1,40 @@
+package org.cryptomator.crypto.aes256;
+
+import java.io.FilterOutputStream;
+import java.io.IOException;
+import java.io.OutputStream;
+
+public class LengthLimitingOutputStream extends FilterOutputStream {
+
+	private final long limit;
+	private volatile long bytesWritten;
+
+	public LengthLimitingOutputStream(OutputStream out, long limit) {
+		super(out);
+		this.limit = limit;
+		this.bytesWritten = 0;
+	}
+
+	@Override
+	public void write(int b) throws IOException {
+		if (bytesWritten < limit) {
+			out.write(b);
+			bytesWritten++;
+		}
+	}
+
+	@Override
+	public void write(byte[] b, int off, int len) throws IOException {
+		final long bytesAvailable = limit - bytesWritten;
+		final int adjustedLen = (int) Math.min(len, bytesAvailable);
+		if (adjustedLen > 0) {
+			out.write(b, off, adjustedLen);
+			bytesWritten += adjustedLen;
+		}
+	}
+
+	public long getBytesWritten() {
+		return bytesWritten;
+	}
+
+}

main/crypto-aes/src/main/java/org/cryptomator/crypto/aes256/LengthObfuscatingInputStream.java

@@ -0,0 +1,129 @@
+package org.cryptomator.crypto.aes256;
+
+import java.io.FilterInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+
+import org.apache.commons.io.IOUtils;
+
+/**
+ * Not thread-safe!
+ */
+public class LengthObfuscatingInputStream extends FilterInputStream {
+
+	private final byte[] padding;
+	private int paddingLength = -1;
+	private long inputBytesRead = 0;
+	private int paddingBytesRead = 0;
+
+	LengthObfuscatingInputStream(InputStream in, byte[] padding) {
+		super(in);
+		this.padding = padding;
+	}
+
+	long getRealInputLength() {
+		return inputBytesRead;
+	}
+
+	private void choosePaddingLengthOnce() {
+		if (paddingLength == -1) {
+			long upperBound = Math.min(Math.max(inputBytesRead / 10, 4096), 16 * 1024 * 1024); // 10% of original bytes (at least 4KiB), but not more than 16MiBs
+			paddingLength = (int) (Math.random() * upperBound);
+		}
+	}
+
+	@Override
+	public int read() throws IOException {
+		final int b = in.read();
+		if (b != -1) {
+			// stream available:
+			inputBytesRead++;
+			return b;
+		} else {
+			choosePaddingLengthOnce();
+			return readFromPadding();
+		}
+	}
+
+	private int readFromPadding() {
+		if (paddingLength == -1) {
+			throw new IllegalStateException("No padding length chosen yet.");
+		}
+
+		if (paddingBytesRead < paddingLength) {
+			// padding available:
+			return padding[paddingBytesRead++ % padding.length];
+		} else {
+			// end of stream AND padding
+			return -1;
+		}
+	}
+
+	@Override
+	public int read(byte[] b, int off, int len) throws IOException {
+		final int bytesRead = IOUtils.read(in, b, off, len); // 0 on EOF
+		inputBytesRead += bytesRead;
+
+		if (bytesRead == len) {
+			return bytesRead;
+		} else if (bytesRead < len) {
+			choosePaddingLengthOnce();
+			final int additionalBytesNeeded = len - bytesRead;
+			final int additionalBytesRead = readFromPadding(b, off + bytesRead, additionalBytesNeeded);
+			return (bytesRead == 0 && additionalBytesRead == 0) ? -1 : bytesRead + additionalBytesRead;
+		} else {
+			// bytesRead > len:
+			throw new IllegalStateException("Read more bytes than requested.");
+		}
+	}
+
+	/**
+	 * @return bytes read from padding (0, if fully read)
+	 */
+	private int readFromPadding(byte[] b, int off, int len) {
+		if (len < 0) {
+			throw new IllegalArgumentException("Length must not be negative");
+		}
+		if (paddingLength == -1) {
+			throw new IllegalStateException("No padding length chosen yet.");
+		}
+
+		final int remainingPadding = paddingLength - paddingBytesRead;
+		if (remainingPadding > len) {
+			// padding available:
+			for (int i = 0; i < len; i++) {
+				b[off + i] = padding[paddingBytesRead++ % padding.length];
+			}
+			return len;
+		} else {
+			// partly available:
+			for (int i = 0; i < remainingPadding; i++) {
+				b[off + i] = padding[paddingBytesRead++ % padding.length];
+			}
+			return remainingPadding;
+		}
+	}
+
+	@Override
+	public long skip(long n) throws IOException {
+		throw new IOException("Skip not supported");
+	}
+
+	@Override
+	public int available() throws IOException {
+		final int inputAvailable = in.available();
+		if (inputAvailable > 0) {
+			return inputAvailable;
+		} else {
+			// remaining padding
+			choosePaddingLengthOnce();
+			return paddingLength - paddingBytesRead;
+		}
+	}
+
+	@Override
+	public boolean markSupported() {
+		return false;
+	}
+
+}

main/crypto-aes/src/main/java/org/cryptomator/crypto/aes256/MacInputStream.java

@@ -1,43 +0,0 @@
-package org.cryptomator.crypto.aes256;
-
-import java.io.FilterInputStream;
-import java.io.IOException;
-import java.io.InputStream;
-
-import javax.crypto.Mac;
-
-/**
- * Updates a {@link Mac} with the bytes read from this stream.
- */
-class MacInputStream extends FilterInputStream {
-
-	private final Mac mac;
-
-	/**
-	 * @param in Stream from which to read contents, which will update the Mac.
-	 * @param mac Mac to be updated during writes.
-	 */
-	public MacInputStream(InputStream in, Mac mac) {
-		super(in);
-		this.mac = mac;
-	}
-
-	@Override
-	public int read() throws IOException {
-		int b = in.read();
-		if (b != -1) {
-			mac.update((byte) b);
-		}
-		return b;
-	}
-
-	@Override
-	public int read(byte[] b, int off, int len) throws IOException {
-		int read = in.read(b, off, len);
-		if (read > 0) {
-			mac.update(b, off, read);
-		}
-		return read;
-	}
-
-}

main/crypto-aes/src/main/java/org/cryptomator/crypto/aes256/MacOutputStream.java

@@ -1,37 +0,0 @@
-package org.cryptomator.crypto.aes256;
-
-import java.io.FilterOutputStream;
-import java.io.IOException;
-import java.io.OutputStream;
-
-import javax.crypto.Mac;
-
-/**
- * Updates a {@link Mac} with the bytes written to this stream.
- */
-class MacOutputStream extends FilterOutputStream {
-
-	private final Mac mac;
-
-	/**
-	 * @param out Stream to redirect contents to after updating the mac.
-	 * @param mac Mac to be updated during writes.
-	 */
-	public MacOutputStream(OutputStream out, Mac mac) {
-		super(out);
-		this.mac = mac;
-	}
-
-	@Override
-	public void write(int b) throws IOException {
-		mac.update((byte) b);
-		out.write(b);
-	}
-
-	@Override
-	public void write(byte[] b, int off, int len) throws IOException {
-		mac.update(b, off, len);
-		out.write(b, off, len);
-	}
-
-}

main/crypto-aes/src/test/java/org/cryptomator/crypto/aes256/Aes256CryptorTest.java

@@ -70,38 +70,6 @@ public class Aes256CryptorTest {
 		}
 	}
 
-	@Test
-	public void testIntegrityAuthentication() throws IOException, DecryptFailedException, EncryptFailedException {
-		// our test plaintext data:
-		final byte[] plaintextData = "Hello World".getBytes();
-		final InputStream plaintextIn = new ByteArrayInputStream(plaintextData);
-
-		// init cryptor:
-		final Aes256Cryptor cryptor = new Aes256Cryptor();
-
-		// encrypt:
-		final ByteBuffer encryptedData = ByteBuffer.allocate(256);
-		final SeekableByteChannel encryptedOut = new ByteBufferBackedSeekableChannel(encryptedData);
-		cryptor.encryptFile(plaintextIn, encryptedOut);
-		IOUtils.closeQuietly(plaintextIn);
-		IOUtils.closeQuietly(encryptedOut);
-
-		encryptedData.position(0);
-
-		// toggle one bit inf first content byte:
-		encryptedData.position(64);
-		final byte fifthByte = encryptedData.get();
-		encryptedData.position(64);
-		encryptedData.put((byte) (fifthByte ^ 0x01));
-
-		encryptedData.position(0);
-
-		// check mac (should return false)
-		final SeekableByteChannel encryptedIn = new ByteBufferBackedSeekableChannel(encryptedData);
-		final boolean authentic = cryptor.isAuthentic(encryptedIn);
-		Assert.assertFalse(authentic);
-	}
-
 	@Test(expected = DecryptFailedException.class)
 	public void testIntegrityViolationDuringDecryption() throws IOException, DecryptFailedException, EncryptFailedException {
 		// our test plaintext data:
@@ -112,7 +80,7 @@ public class Aes256CryptorTest {
 		final Aes256Cryptor cryptor = new Aes256Cryptor();
 
 		// encrypt:
-		final ByteBuffer encryptedData = ByteBuffer.allocate(256);
+		final ByteBuffer encryptedData = ByteBuffer.allocate(104 + plaintextData.length + 4096);
 		final SeekableByteChannel encryptedOut = new ByteBufferBackedSeekableChannel(encryptedData);
 		cryptor.encryptFile(plaintextIn, encryptedOut);
 		IOUtils.closeQuietly(plaintextIn);
@@ -131,7 +99,7 @@ public class Aes256CryptorTest {
 		// decrypt modified content (should fail with DecryptFailedException):
 		final SeekableByteChannel encryptedIn = new ByteBufferBackedSeekableChannel(encryptedData);
 		final ByteArrayOutputStream plaintextOut = new ByteArrayOutputStream();
-		cryptor.decryptFile(encryptedIn, plaintextOut);
+		cryptor.decryptFile(encryptedIn, plaintextOut, true);
 	}
 
 	@Test
@@ -144,7 +112,7 @@ public class Aes256CryptorTest {
 		final Aes256Cryptor cryptor = new Aes256Cryptor();
 
 		// encrypt:
-		final ByteBuffer encryptedData = ByteBuffer.allocate(256);
+		final ByteBuffer encryptedData = ByteBuffer.allocate(104 + plaintextData.length + 4096);
 		final SeekableByteChannel encryptedOut = new ByteBufferBackedSeekableChannel(encryptedData);
 		cryptor.encryptFile(plaintextIn, encryptedOut);
 		IOUtils.closeQuietly(plaintextIn);
@@ -159,7 +127,7 @@ public class Aes256CryptorTest {
 
 		// decrypt:
 		final ByteArrayOutputStream plaintextOut = new ByteArrayOutputStream();
-		final Long numDecryptedBytes = cryptor.decryptFile(encryptedIn, plaintextOut);
+		final Long numDecryptedBytes = cryptor.decryptFile(encryptedIn, plaintextOut, true);
 		IOUtils.closeQuietly(encryptedIn);
 		IOUtils.closeQuietly(plaintextOut);
 		Assert.assertEquals(filesize.longValue(), numDecryptedBytes.longValue());
@@ -171,10 +139,10 @@ public class Aes256CryptorTest {
 
 	@Test
 	public void testPartialDecryption() throws IOException, DecryptFailedException, WrongPasswordException, UnsupportedKeyLengthException, EncryptFailedException {
-		// our test plaintext data:
-		final byte[] plaintextData = new byte[65536 * Integer.BYTES];
+		// 8MiB test plaintext data:
+		final byte[] plaintextData = new byte[2097152 * Integer.BYTES];
 		final ByteBuffer bbIn = ByteBuffer.wrap(plaintextData);
-		for (int i = 0; i < 65536; i++) {
+		for (int i = 0; i < 2097152; i++) {
 			bbIn.putInt(i);
 		}
 		final InputStream plaintextIn = new ByteArrayInputStream(plaintextData);
@@ -183,7 +151,7 @@ public class Aes256CryptorTest {
 		final Aes256Cryptor cryptor = new Aes256Cryptor();
 
 		// encrypt:
-		final ByteBuffer encryptedData = ByteBuffer.allocate((int) (96 + plaintextData.length * 1.2));
+		final ByteBuffer encryptedData = ByteBuffer.allocate((int) (104 + plaintextData.length * 1.2));
 		final SeekableByteChannel encryptedOut = new ByteBufferBackedSeekableChannel(encryptedData);
 		cryptor.encryptFile(plaintextIn, encryptedOut);
 		IOUtils.closeQuietly(plaintextIn);
@@ -194,14 +162,14 @@ public class Aes256CryptorTest {
 		// decrypt:
 		final SeekableByteChannel encryptedIn = new ByteBufferBackedSeekableChannel(encryptedData);
 		final ByteArrayOutputStream plaintextOut = new ByteArrayOutputStream();
-		final Long numDecryptedBytes = cryptor.decryptRange(encryptedIn, plaintextOut, 25000 * Integer.BYTES, 30000 * Integer.BYTES);
+		final Long numDecryptedBytes = cryptor.decryptRange(encryptedIn, plaintextOut, 260000 * Integer.BYTES, 4000 * Integer.BYTES, true);
 		IOUtils.closeQuietly(encryptedIn);
 		IOUtils.closeQuietly(plaintextOut);
 		Assert.assertTrue(numDecryptedBytes > 0);
 
 		// check decrypted data:
 		final byte[] result = plaintextOut.toByteArray();
-		final byte[] expected = Arrays.copyOfRange(plaintextData, 25000 * Integer.BYTES, 55000 * Integer.BYTES);
+		final byte[] expected = Arrays.copyOfRange(plaintextData, 260000 * Integer.BYTES, 264000 * Integer.BYTES);
 		Assert.assertArrayEquals(expected, result);
 	}
 

main/crypto-aes/src/test/resources/log4j2.xml

@@ -0,0 +1,33 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<!--
+  Copyright (c) 2014 Markus Kreusch
+  This file is licensed under the terms of the MIT license.
+  See the LICENSE.txt file for more info.
+  
+  Contributors:
+      Sebastian Stenzel - log4j config for WebDAV unit tests
+-->
+<Configuration status="WARN">
+
+	<Appenders>
+		<Console name="Console" target="SYSTEM_OUT">
+			<PatternLayout pattern="%16d %-5p [%c{1}:%L] %m%n" />
+			<ThresholdFilter level="WARN" onMatch="DENY" onMismatch="ACCEPT" />
+		</Console>
+		<Console name="StdErr" target="SYSTEM_ERR">
+			<PatternLayout pattern="%16d %-5p [%c{1}:%L] %m%n" />
+			<ThresholdFilter level="WARN" onMatch="ACCEPT" onMismatch="DENY" />
+		</Console>
+	</Appenders>
+
+	<Loggers>
+		<!-- show our own debug messages: -->
+		<Logger name="org.cryptomator" level="DEBUG" />
+		<!-- mute dependencies: -->
+		<Root level="INFO">
+			<AppenderRef ref="Console" />
+			<AppenderRef ref="StdErr" />
+		</Root>
+	</Loggers>
+
+</Configuration>

main/crypto-api/pom.xml

@@ -12,7 +12,7 @@
 	<parent>
 		<groupId>org.cryptomator</groupId>
 		<artifactId>main</artifactId>
-		<version>0.7.0</version>
+		<version>0.8.2</version>
 	</parent>
 	<artifactId>crypto-api</artifactId>
 	<name>Cryptomator cryptographic module API</name>

main/crypto-api/src/main/java/org/cryptomator/crypto/AbstractCryptorDecorator.java

@@ -53,18 +53,13 @@ public class AbstractCryptorDecorator implements Cryptor {
 	}
 
 	@Override
-	public boolean isAuthentic(SeekableByteChannel encryptedFile) throws IOException {
-		return cryptor.isAuthentic(encryptedFile);
+	public Long decryptFile(SeekableByteChannel encryptedFile, OutputStream plaintextFile, boolean authenticate) throws IOException, DecryptFailedException {
+		return cryptor.decryptFile(encryptedFile, plaintextFile, authenticate);
 	}
 
 	@Override
-	public Long decryptFile(SeekableByteChannel encryptedFile, OutputStream plaintextFile) throws IOException, DecryptFailedException {
-		return cryptor.decryptFile(encryptedFile, plaintextFile);
-	}
-
-	@Override
-	public Long decryptRange(SeekableByteChannel encryptedFile, OutputStream plaintextFile, long pos, long length) throws IOException, DecryptFailedException {
-		return cryptor.decryptRange(encryptedFile, plaintextFile, pos, length);
+	public Long decryptRange(SeekableByteChannel encryptedFile, OutputStream plaintextFile, long pos, long length, boolean authenticate) throws IOException, DecryptFailedException {
+		return cryptor.decryptRange(encryptedFile, plaintextFile, pos, length, authenticate);
 	}
 
 	@Override

main/crypto-api/src/main/java/org/cryptomator/crypto/Cryptor.java

@@ -75,16 +75,11 @@ public interface Cryptor extends Destroyable {
 	 */
 	Long decryptedContentLength(SeekableByteChannel encryptedFile) throws IOException, MacAuthenticationFailedException;
 
-	/**
-	 * @return true, if the stored MAC matches the calculated one.
-	 */
-	boolean isAuthentic(SeekableByteChannel encryptedFile) throws IOException;
-
 	/**
 	 * @return Number of decrypted bytes. This might not be equal to the encrypted file size due to optional metadata written to it.
 	 * @throws DecryptFailedException If decryption failed
 	 */
-	Long decryptFile(SeekableByteChannel encryptedFile, OutputStream plaintextFile) throws IOException, DecryptFailedException;
+	Long decryptFile(SeekableByteChannel encryptedFile, OutputStream plaintextFile, boolean authenticate) throws IOException, DecryptFailedException;
 
 	/**
 	 * @param pos First byte (inclusive)
@@ -92,7 +87,7 @@ public interface Cryptor extends Destroyable {
 	 * @return Number of decrypted bytes. This might not be equal to the number of bytes requested due to potential overheads.
 	 * @throws DecryptFailedException If decryption failed
 	 */
-	Long decryptRange(SeekableByteChannel encryptedFile, OutputStream plaintextFile, long pos, long length) throws IOException, DecryptFailedException;
+	Long decryptRange(SeekableByteChannel encryptedFile, OutputStream plaintextFile, long pos, long length, boolean authenticate) throws IOException, DecryptFailedException;
 
 	/**
 	 * @return Number of encrypted bytes. This might not be equal to the encrypted file size due to optional metadata written to it.

main/crypto-api/src/main/java/org/cryptomator/crypto/SamplingCryptorDecorator.java

@@ -45,15 +45,15 @@ public class SamplingCryptorDecorator extends AbstractCryptorDecorator implement
 	/* Cryptor */
 
 	@Override
-	public Long decryptFile(SeekableByteChannel encryptedFile, OutputStream plaintextFile) throws IOException, DecryptFailedException {
-		final OutputStream countingInputStream = new CountingOutputStream(decryptedBytes, plaintextFile);
-		return cryptor.decryptFile(encryptedFile, countingInputStream);
+	public Long decryptFile(SeekableByteChannel encryptedFile, OutputStream plaintextFile, boolean authenticate) throws IOException, DecryptFailedException {
+		final OutputStream countingOutputStream = new CountingOutputStream(decryptedBytes, plaintextFile);
+		return cryptor.decryptFile(encryptedFile, countingOutputStream, authenticate);
 	}
 
 	@Override
-	public Long decryptRange(SeekableByteChannel encryptedFile, OutputStream plaintextFile, long pos, long length) throws IOException, DecryptFailedException {
-		final OutputStream countingInputStream = new CountingOutputStream(decryptedBytes, plaintextFile);
-		return cryptor.decryptRange(encryptedFile, countingInputStream, pos, length);
+	public Long decryptRange(SeekableByteChannel encryptedFile, OutputStream plaintextFile, long pos, long length, boolean authenticate) throws IOException, DecryptFailedException {
+		final OutputStream countingOutputStream = new CountingOutputStream(decryptedBytes, plaintextFile);
+		return cryptor.decryptRange(encryptedFile, countingOutputStream, pos, length, authenticate);
 	}
 
 	@Override

main/crypto-api/src/main/java/org/cryptomator/crypto/exceptions/CryptingException.java

@@ -0,0 +1,15 @@
+package org.cryptomator.crypto.exceptions;
+
+import java.io.IOException;
+
+public class CryptingException extends IOException {
+	private static final long serialVersionUID = -6622699014483319376L;
+
+	public CryptingException(String string) {
+		super(string);
+	}
+
+	public CryptingException(String string, Throwable t) {
+		super(string, t);
+	}
+}

main/crypto-api/src/main/java/org/cryptomator/crypto/exceptions/DecryptFailedException.java

@@ -1,6 +1,6 @@
 package org.cryptomator.crypto.exceptions;
 
-public class DecryptFailedException extends StorageCryptingException {
+public class DecryptFailedException extends CryptingException {
 	private static final long serialVersionUID = -3855673600374897828L;
 
 	public DecryptFailedException(Throwable t) {

main/crypto-api/src/main/java/org/cryptomator/crypto/exceptions/EncryptFailedException.java

@@ -1,8 +1,12 @@
 package org.cryptomator.crypto.exceptions;
 
-public class EncryptFailedException extends StorageCryptingException {
+public class EncryptFailedException extends CryptingException {
 	private static final long serialVersionUID = -3855673600374897828L;
 
+	public EncryptFailedException(Throwable t) {
+		super("Encryption failed.", t);
+	}
+
 	public EncryptFailedException(String msg) {
 		super(msg);
 	}

main/crypto-api/src/main/java/org/cryptomator/crypto/exceptions/MasterkeyDecryptionException.java

@@ -0,0 +1,11 @@
+package org.cryptomator.crypto.exceptions;
+
+public class MasterkeyDecryptionException extends Exception {
+
+	private static final long serialVersionUID = -6241452734672333206L;
+
+	public MasterkeyDecryptionException(String string) {
+		super(string);
+	}
+
+}

main/crypto-api/src/main/java/org/cryptomator/crypto/exceptions/StorageCryptingException.java

@@ -1,13 +0,0 @@
-package org.cryptomator.crypto.exceptions;
-
-public class StorageCryptingException extends Exception {
-	private static final long serialVersionUID = -6622699014483319376L;
-	
-	public StorageCryptingException(String string) {
-		super(string);
-	}
-	
-	public StorageCryptingException(String string, Throwable t) {
-		super(string, t);
-	}
-}

main/crypto-api/src/main/java/org/cryptomator/crypto/exceptions/UnsupportedKeyLengthException.java

@@ -1,6 +1,6 @@
 package org.cryptomator.crypto.exceptions;
 
-public class UnsupportedKeyLengthException extends StorageCryptingException {
+public class UnsupportedKeyLengthException extends MasterkeyDecryptionException {
 	private static final long serialVersionUID = 8114147446419390179L;
 
 	private final int requestedLength;

main/crypto-api/src/main/java/org/cryptomator/crypto/exceptions/WrongPasswordException.java

@@ -1,6 +1,6 @@
 package org.cryptomator.crypto.exceptions;
 
-public class WrongPasswordException extends StorageCryptingException {
+public class WrongPasswordException extends MasterkeyDecryptionException {
 	private static final long serialVersionUID = -602047799678568780L;
 
 	public WrongPasswordException() {

main/installer-debian/pom.xml

@@ -3,7 +3,7 @@
 	<parent>
 		<groupId>org.cryptomator</groupId>
 		<artifactId>main</artifactId>
-		<version>0.7.0</version>
+		<version>0.8.2</version>
 	</parent>
 	<artifactId>installer-debian</artifactId>
 	<packaging>pom</packaging>
@@ -24,6 +24,15 @@
 
 	<build>
 		<plugins>
+			<plugin>
+				<artifactId>maven-dependency-plugin</artifactId>
+				<executions>
+					<execution>
+						<id>copy-libs</id>
+						<phase>prepare-package</phase>
+					</execution>
+				</executions>
+			</plugin>
 			<plugin>
 				<artifactId>maven-antrun-plugin</artifactId>
 				<version>1.7</version>
@@ -37,15 +46,34 @@
 						<configuration>
 							<target xmlns:fx="javafx:com.sun.javafx.tools.ant">
 								<taskdef uri="javafx:com.sun.javafx.tools.ant" resource="com/sun/javafx/tools/ant/antlib.xml" classpath="${project.basedir}:${javafx.tools.ant.jar}" />
+								
+								<!-- Define application to build -->
+								<fx:application id="fxApp" name="${javafx.application.name}" version="${project.version}" mainClass="${exec.mainClass}" />
+								
+								<!-- Create main application jar -->
+								<fx:jar destfile="${project.build.directory}/Cryptomator-${project.parent.version}.jar">
+									<fx:application refid="fxApp" />
+									<fx:fileset dir="${project.build.directory}" includes="libs/ui-${project.version}.jar"/>
+									<fx:resources>
+										<fx:fileset dir="${project.build.directory}" type="jar" includes="libs/*.jar" excludes="libs/ui-${project.version}.jar" />
+									</fx:resources>
+									<fx:manifest>
+										<fx:attribute name="Implementation-Vendor" value="cryptomator.org" />
+										<fx:attribute name="Implementation-Version" value="${project.version}" />
+									</fx:manifest>
+								</fx:jar>
 
+								<!-- Create native package -->
 								<fx:deploy nativeBundles="deb" outdir="${project.build.directory}" outfile="Cryptomator-${project.parent.version}" verbose="true">
-									<fx:application name="${javafx.application.name}" version="${project.version}" mainClass="${exec.mainClass}" />
+									<fx:application refid="fxApp"/>
 									<fx:info title="${javafx.application.name}" vendor="cryptomator.org" copyright="cryptomator.org" license="MIT" category="Utility" />
 									<fx:platform javafx="2.2+" j2se="8.0">
 										<fx:property name="logPath" value="~/.Cryptomator/cryptomator.log" />
+										<fx:jvmarg value="-Xmx2048m"/>
 									</fx:platform>
 									<fx:resources>
-										<fx:fileset dir="../target/" includes="Cryptomator-${project.parent.version}.jar" />
+										<fx:fileset dir="${project.build.directory}" type="jar" includes="Cryptomator-${project.parent.version}.jar"/>
+                                    	<fx:fileset dir="${project.build.directory}" type="jar" includes="libs/*.jar" excludes="libs/ui-${project.version}.jar"/>
 									</fx:resources>
 									<fx:permissions elevated="false" />
 									<fx:preferences install="true" />

main/installer-osx/pom.xml

@@ -3,7 +3,7 @@
 	<parent>
 		<groupId>org.cryptomator</groupId>
 		<artifactId>main</artifactId>
-		<version>0.7.0</version>
+		<version>0.8.2</version>
 	</parent>
 	<artifactId>installer-osx</artifactId>
 	<packaging>pom</packaging>
@@ -24,6 +24,15 @@
 
 	<build>
 		<plugins>
+			<plugin>
+				<artifactId>maven-dependency-plugin</artifactId>
+				<executions>
+					<execution>
+						<id>copy-libs</id>
+						<phase>prepare-package</phase>
+					</execution>
+				</executions>
+			</plugin>
 			<plugin>
 				<artifactId>maven-antrun-plugin</artifactId>
 				<version>1.7</version>
@@ -37,15 +46,34 @@
 						<configuration>
 							<target xmlns:fx="javafx:com.sun.javafx.tools.ant">
 								<taskdef uri="javafx:com.sun.javafx.tools.ant" resource="com/sun/javafx/tools/ant/antlib.xml" classpath="${project.basedir}:${javafx.tools.ant.jar}" />
+								
+								<!-- Define application to build -->
+								<fx:application id="fxApp" name="${javafx.application.name}" version="${project.version}" mainClass="${exec.mainClass}" />
+								
+								<!-- Create main application jar -->
+								<fx:jar destfile="${project.build.directory}/Cryptomator-${project.parent.version}.jar">
+									<fx:application refid="fxApp" />
+									<fx:fileset dir="${project.build.directory}" includes="libs/ui-${project.version}.jar"/>
+									<fx:resources>
+										<fx:fileset dir="${project.build.directory}" type="jar" includes="libs/*.jar" excludes="libs/ui-${project.version}.jar" />
+									</fx:resources>
+									<fx:manifest>
+										<fx:attribute name="Implementation-Vendor" value="cryptomator.org" />
+										<fx:attribute name="Implementation-Version" value="${project.version}" />
+									</fx:manifest>
+								</fx:jar>
 
+								<!-- Create native package -->
 								<fx:deploy nativeBundles="dmg" outdir="${project.build.directory}" outfile="Cryptomator-${project.parent.version}" verbose="true">
-									<fx:application name="${javafx.application.name}" version="${project.version}" mainClass="${exec.mainClass}" />
+									<fx:application refid="fxApp"/>
 									<fx:info title="${javafx.application.name}" vendor="cryptomator.org" copyright="cryptomator.org" license="MIT" category="Utility" />
 									<fx:platform javafx="2.2+" j2se="8.0">
 										<fx:property name="logPath" value="~/Library/Logs/Cryptomator/cryptomator.log" />
+										<fx:jvmarg value="-Xmx2048m"/>
 									</fx:platform>
 									<fx:resources>
-										<fx:fileset dir="../target/" includes="Cryptomator-${project.parent.version}.jar" />
+										<fx:fileset dir="${project.build.directory}" type="jar" includes="Cryptomator-${project.parent.version}.jar"/>
+                                    	<fx:fileset dir="${project.build.directory}" type="jar" includes="libs/*.jar" excludes="libs/ui-${project.version}.jar"/>
 									</fx:resources>
 									<fx:permissions elevated="false" />
 									<fx:preferences install="true" />

main/installer-win-portable/pom.xml

@@ -3,7 +3,7 @@
 	<parent>
 		<groupId>org.cryptomator</groupId>
 		<artifactId>main</artifactId>
-		<version>0.7.0</version>
+		<version>0.8.2</version>
 	</parent>
 	<artifactId>installer-win-portable</artifactId>
 	<packaging>pom</packaging>
@@ -24,6 +24,15 @@
 
 	<build>
 		<plugins>
+			<plugin>
+				<artifactId>maven-dependency-plugin</artifactId>
+				<executions>
+					<execution>
+						<id>copy-libs</id>
+						<phase>prepare-package</phase>
+					</execution>
+				</executions>
+			</plugin>
 			<plugin>
 				<artifactId>maven-antrun-plugin</artifactId>
 				<version>1.7</version>
@@ -37,16 +46,34 @@
 						<configuration>
 							<target xmlns:fx="javafx:com.sun.javafx.tools.ant">
 								<taskdef uri="javafx:com.sun.javafx.tools.ant" resource="com/sun/javafx/tools/ant/antlib.xml" classpath="${project.basedir}:${javafx.tools.ant.jar}" />
+								
+								<!-- Define application to build -->
+								<fx:application id="fxApp" name="${javafx.application.name}" version="${project.version}" mainClass="${exec.mainClass}" />
+								
+								<!-- Create main application jar -->
+								<fx:jar destfile="${project.build.directory}/Cryptomator-${project.parent.version}.jar">
+									<fx:application refid="fxApp" />
+									<fx:fileset dir="${project.build.directory}" includes="libs/ui-${project.version}.jar"/>
+									<fx:resources>
+										<fx:fileset dir="${project.build.directory}" type="jar" includes="libs/*.jar" excludes="libs/ui-${project.version}.jar" />
+									</fx:resources>
+									<fx:manifest>
+										<fx:attribute name="Implementation-Vendor" value="cryptomator.org" />
+										<fx:attribute name="Implementation-Version" value="${project.version}" />
+									</fx:manifest>
+								</fx:jar>
 
+								<!-- Create native package -->
 								<fx:deploy nativeBundles="exe" outdir="${project.build.directory}" outfile="Cryptomator-${project.parent.version}" verbose="true">
-									<fx:application name="${javafx.application.name}" version="${project.version}" mainClass="${exec.mainClass}" />
+									<fx:application refid="fxApp"/>
 									<fx:info title="${javafx.application.name}" vendor="cryptomator.org" copyright="cryptomator.org" license="MIT" category="Utility" />
 									<fx:platform javafx="2.2+" j2se="8.0">
 										<fx:property name="settingsPath" value="./settings.json" />
 										<fx:property name="logPath" value="cryptomator.log" />
 									</fx:platform>
 									<fx:resources>
-										<fx:fileset dir="../target/" includes="Cryptomator-${project.parent.version}.jar" />
+										<fx:fileset dir="${project.build.directory}" type="jar" includes="Cryptomator-${project.parent.version}.jar"/>
+                                    	<fx:fileset dir="${project.build.directory}" type="jar" includes="libs/*.jar" excludes="libs/ui-${project.version}.jar"/>
 									</fx:resources>
 									<fx:permissions elevated="false" />
 									<fx:preferences install="false" menu="false" shortcut="false" />

main/installer-win/pom.xml

@@ -3,7 +3,7 @@
 	<parent>
 		<groupId>org.cryptomator</groupId>
 		<artifactId>main</artifactId>
-		<version>0.7.0</version>
+		<version>0.8.2</version>
 	</parent>
 	<artifactId>installer-win</artifactId>
 	<packaging>pom</packaging>
@@ -24,6 +24,15 @@
 
 	<build>
 		<plugins>
+			<plugin>
+				<artifactId>maven-dependency-plugin</artifactId>
+				<executions>
+					<execution>
+						<id>copy-libs</id>
+						<phase>prepare-package</phase>
+					</execution>
+				</executions>
+			</plugin>
 			<plugin>
 				<artifactId>maven-antrun-plugin</artifactId>
 				<version>1.7</version>
@@ -37,15 +46,33 @@
 						<configuration>
 							<target xmlns:fx="javafx:com.sun.javafx.tools.ant">
 								<taskdef uri="javafx:com.sun.javafx.tools.ant" resource="com/sun/javafx/tools/ant/antlib.xml" classpath="${project.basedir}:${javafx.tools.ant.jar}" />
+								
+								<!-- Define application to build -->
+								<fx:application id="fxApp" name="${javafx.application.name}" version="${project.version}" mainClass="${exec.mainClass}" />
+								
+								<!-- Create main application jar -->
+								<fx:jar destfile="${project.build.directory}/Cryptomator-${project.parent.version}.jar">
+									<fx:application refid="fxApp" />
+									<fx:fileset dir="${project.build.directory}" includes="libs/ui-${project.version}.jar"/>
+									<fx:resources>
+										<fx:fileset dir="${project.build.directory}" type="jar" includes="libs/*.jar" excludes="libs/ui-${project.version}.jar" />
+									</fx:resources>
+									<fx:manifest>
+										<fx:attribute name="Implementation-Vendor" value="cryptomator.org" />
+										<fx:attribute name="Implementation-Version" value="${project.version}" />
+									</fx:manifest>
+								</fx:jar>
 
+								<!-- Create native package -->
 								<fx:deploy nativeBundles="exe" outdir="${project.build.directory}" outfile="Cryptomator-${project.parent.version}" verbose="true">
-									<fx:application name="${javafx.application.name}" version="${project.version}" mainClass="${exec.mainClass}" />
+									<fx:application refid="fxApp"/>
 									<fx:info title="${javafx.application.name}" vendor="cryptomator.org" copyright="cryptomator.org" license="MIT" category="Utility" />
 									<fx:platform javafx="2.2+" j2se="8.0" >
 										<fx:property name="logPath" value="%appdata%/Cryptomator/cryptomator.log" />
 									</fx:platform>
 									<fx:resources>
-										<fx:fileset dir="../target/" includes="Cryptomator-${project.parent.version}.jar" />
+										<fx:fileset dir="${project.build.directory}" type="jar" includes="Cryptomator-${project.parent.version}.jar"/>
+                                    	<fx:fileset dir="${project.build.directory}" type="jar" includes="libs/*.jar" excludes="libs/ui-${project.version}.jar"/>
 									</fx:resources>
 									<fx:permissions elevated="false" />
 									<fx:preferences install="true" />

main/pom.xml

@@ -11,7 +11,7 @@
 	<modelVersion>4.0.0</modelVersion>
 	<groupId>org.cryptomator</groupId>
 	<artifactId>main</artifactId>
-	<version>0.7.0</version>
+	<version>0.8.2</version>
 	<packaging>pom</packaging>
 	<name>Cryptomator</name>
 
@@ -211,9 +211,35 @@
 				<module>installer-win-portable</module>
 			</modules>
 		</profile>
+		<profile>
+			<id>uber-jar</id>
+			<modules>
+				<module>uber-jar</module>
+			</modules>
+		</profile>
 	</profiles>
 
 	<build>
+		<pluginManagement>
+			<plugins>
+				<plugin>
+					<groupId>org.apache.maven.plugins</groupId>
+					<artifactId>maven-dependency-plugin</artifactId>
+					<executions>
+						<execution>
+							<id>copy-libs</id>
+							<goals>
+								<goal>copy-dependencies</goal>
+							</goals>
+							<configuration>
+								<outputDirectory>${project.build.directory}/libs</outputDirectory>
+								<includeScope>runtime</includeScope>
+							</configuration>
+						</execution>
+					</executions>
+				</plugin>
+			</plugins>
+		</pluginManagement>
 		<plugins>
 			<plugin>
 				<groupId>org.apache.maven.plugins</groupId>

main/uber-jar/pom.xml

@@ -0,0 +1,57 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  Copyright (c) 2014 Sebastian Stenzel
+  This file is licensed under the terms of the MIT license.
+  See the LICENSE.txt file for more info.
+  
+  Contributors:
+      Sebastian Stenzel - initial API and implementation
+-->
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<parent>
+		<groupId>org.cryptomator</groupId>
+		<artifactId>main</artifactId>
+		<version>0.8.2</version>
+	</parent>
+	<artifactId>uber-jar</artifactId>
+	<packaging>pom</packaging>
+	<name>Single über jar with all dependencies</name>
+
+	<dependencies>
+		<dependency>
+			<groupId>org.cryptomator</groupId>
+			<artifactId>ui</artifactId>
+		</dependency>
+	</dependencies>
+
+	<build>
+		<plugins>
+			<plugin>
+				<artifactId>maven-assembly-plugin</artifactId>
+				<executions>
+					<execution>
+						<id>make-assembly</id>
+						<phase>package</phase>
+						<goals>
+							<goal>single</goal>
+						</goals>
+					</execution>
+				</executions>
+				<configuration>
+					<finalName>Cryptomator-${project.parent.version}</finalName>
+					<descriptorRefs>
+						<descriptorRef>jar-with-dependencies</descriptorRef>
+					</descriptorRefs>
+					<appendAssemblyId>false</appendAssemblyId>
+					<archive>
+						<manifestEntries>
+							<Main-Class>org.cryptomator.ui.Cryptomator</Main-Class>
+							<Implementation-Version>${project.version}</Implementation-Version>
+						</manifestEntries>
+					</archive>
+				</configuration>
+			</plugin>
+		</plugins>
+	</build>
+</project>

main/ui/pom.xml

@@ -12,7 +12,7 @@
 	<parent>
 		<groupId>org.cryptomator</groupId>
 		<artifactId>main</artifactId>
-		<version>0.7.0</version>
+		<version>0.8.2</version>
 	</parent>
 	<artifactId>ui</artifactId>
 	<name>Cryptomator GUI</name>
@@ -32,6 +32,12 @@
 			<groupId>com.fasterxml.jackson.core</groupId>
 			<artifactId>jackson-databind</artifactId>
 		</dependency>
+	
+		<!-- Guava -->
+		<dependency>
+			<groupId>com.google.guava</groupId>
+			<artifactId>guava</artifactId>
+		</dependency>
 
 		<!-- apache commons -->
 		<dependency>
@@ -53,35 +59,4 @@
 			<artifactId>guice</artifactId>
 		</dependency>
 	</dependencies>
-	
-	<build>
-		<plugins>
-			<plugin>
-				<artifactId>maven-assembly-plugin</artifactId>
-				<executions>
-					<execution>
-						<id>make-assembly</id>
-						<phase>package</phase>
-						<goals>
-							<goal>single</goal>
-						</goals>
-					</execution>
-				</executions>
-				<configuration>
-					<outputDirectory>${project.parent.build.directory}</outputDirectory>
-					<finalName>Cryptomator-${project.parent.version}</finalName>
-					<descriptorRefs>
-						<descriptorRef>jar-with-dependencies</descriptorRef>
-					</descriptorRefs>
-					<appendAssemblyId>false</appendAssemblyId>
-					<archive>
-						<manifestEntries>
-							<Main-Class>org.cryptomator.ui.Cryptomator</Main-Class>
-							<Implementation-Version>${project.version}</Implementation-Version>
-						</manifestEntries>
-					</archive>
-				</configuration>
-			</plugin>
-		</plugins>
-	</build>
 </project>

main/ui/src/main/java/org/cryptomator/ui/controllers/ChangePasswordController.java

@@ -20,7 +20,6 @@ import javafx.scene.control.Button;
 import javafx.scene.control.Hyperlink;
 import javafx.scene.text.Text;
 
-import org.cryptomator.crypto.exceptions.DecryptFailedException;
 import org.cryptomator.crypto.exceptions.UnsupportedKeyLengthException;
 import org.cryptomator.crypto.exceptions.UnsupportedVaultException;
 import org.cryptomator.crypto.exceptions.WrongPasswordException;
@@ -109,7 +108,7 @@ public class ChangePasswordController implements Initializable {
 		try (final InputStream masterKeyInputStream = Files.newInputStream(masterKeyPath, StandardOpenOption.READ)) {
 			vault.getCryptor().decryptMasterKey(masterKeyInputStream, oldPassword);
 			Files.copy(masterKeyPath, masterKeyBackupPath, StandardCopyOption.REPLACE_EXISTING);
-		} catch (DecryptFailedException | IOException ex) {
+		} catch (IOException ex) {
 			messageText.setText(rb.getString("changePassword.errorMessage.decryptionFailed"));
 			LOG.error("Decryption failed for technical reasons.", ex);
 			newPasswordField.swipe();

main/ui/src/main/java/org/cryptomator/ui/controllers/MacWarningsController.java

@@ -1,33 +1,83 @@
 package org.cryptomator.ui.controllers;
 
+import java.net.URL;
+import java.util.ResourceBundle;
+import java.util.stream.Collectors;
+
 import javafx.application.Application;
+import javafx.beans.Observable;
+import javafx.beans.property.BooleanProperty;
+import javafx.beans.property.ReadOnlyStringWrapper;
+import javafx.beans.property.SimpleBooleanProperty;
+import javafx.beans.value.ChangeListener;
+import javafx.beans.value.ObservableValue;
+import javafx.beans.value.WeakChangeListener;
+import javafx.collections.FXCollections;
+import javafx.collections.ListChangeListener;
 import javafx.collections.ListChangeListener.Change;
 import javafx.collections.ObservableList;
-import javafx.collections.WeakListChangeListener;
 import javafx.event.ActionEvent;
 import javafx.fxml.FXML;
+import javafx.fxml.Initializable;
+import javafx.scene.control.Button;
 import javafx.scene.control.ListView;
+import javafx.scene.control.cell.CheckBoxListCell;
 import javafx.stage.Stage;
+import javafx.util.StringConverter;
 
 import javax.inject.Inject;
 
-public class MacWarningsController {
+import org.cryptomator.ui.model.Vault;
+
+public class MacWarningsController implements Initializable {
 
 	@FXML
-	private ListView<String> warningsList;
+	private ListView<Warning> warningsList;
 
-	private Stage stage;
+	@FXML
+	private Button whitelistButton;
 
 	private final Application application;
+	private final ObservableList<Warning> warnings = FXCollections.observableArrayList();
+	private final ListChangeListener<String> unauthenticatedResourcesChangeListener = this::unauthenticatedResourcesDidChange;
+	private final ChangeListener<Boolean> stageVisibilityChangeListener = this::windowVisibilityDidChange;
+	private Stage stage;
+	private Vault vault;
+	private ResourceBundle rb;
 
 	@Inject
 	public MacWarningsController(Application application) {
 		this.application = application;
 	}
 
+	@Override
+	public void initialize(URL location, ResourceBundle rb) {
+		this.rb = rb;
+		warnings.addListener(this::warningsDidInvalidate);
+		warningsList.setItems(warnings);
+		warningsList.setCellFactory(CheckBoxListCell.forListView(Warning::selectedProperty, new StringConverter<Warning>() {
+
+			@Override
+			public String toString(Warning object) {
+				return object.getName();
+			}
+
+			@Override
+			public Warning fromString(String string) {
+				return null;
+			}
+
+		}));
+	}
+
 	@FXML
-	private void didClickDismissButton(ActionEvent event) {
-		stage.hide();
+	private void didClickWhitelistButton(ActionEvent event) {
+		warnings.filtered(w -> w.isSelected()).stream().forEach(w -> {
+			final String resourceToBeWhitelisted = w.getName();
+			vault.getWhitelistedResourcesWithInvalidMac().add(resourceToBeWhitelisted);
+			vault.getNamesOfResourcesWithInvalidMac().remove(resourceToBeWhitelisted);
+		});
+		warnings.removeIf(w -> w.isSelected());
 	}
 
 	@FXML
@@ -35,24 +85,70 @@ public class MacWarningsController {
 		application.getHostServices().showDocument("https://cryptomator.org/help.html#macWarning");
 	}
 
-	public void setMacWarnings(ObservableList<String> macWarnings) {
-		this.warningsList.setItems(macWarnings);
-		this.warningsList.getItems().addListener(new WeakListChangeListener<String>(this::warningsDidChange));
-	}
-
-	// closes this window automatically, if all warnings disappeared (e.g. due to an unmount event)
-	private void warningsDidChange(Change<? extends String> change) {
-		if (change.getList().isEmpty()) {
-			stage.hide();
+	private void unauthenticatedResourcesDidChange(Change<? extends String> change) {
+		while (change.next()) {
+			if (change.wasAdded()) {
+				warnings.addAll(change.getAddedSubList().stream().map(Warning::new).collect(Collectors.toList()));
+			} else if (change.wasRemoved()) {
+				change.getRemoved().forEach(str -> {
+					warnings.removeIf(w -> str.equals(w.name.get()));
+				});
+			}
 		}
 	}
 
-	public Stage getStage() {
-		return stage;
+	private void warningsDidInvalidate(Observable observable) {
+		disableWhitelistButtonIfNothingSelected();
+	}
+
+	private void windowVisibilityDidChange(ObservableValue<? extends Boolean> observable, Boolean oldValue, Boolean newValue) {
+		if (Boolean.TRUE.equals(newValue)) {
+			stage.setTitle(String.format(rb.getString("macWarnings.windowTitle"), vault.getName()));
+			warnings.addAll(vault.getNamesOfResourcesWithInvalidMac().stream().map(Warning::new).collect(Collectors.toList()));
+			vault.getNamesOfResourcesWithInvalidMac().addListener(this.unauthenticatedResourcesChangeListener);
+		} else {
+			vault.getNamesOfResourcesWithInvalidMac().clear();
+			vault.getNamesOfResourcesWithInvalidMac().removeListener(this.unauthenticatedResourcesChangeListener);
+		}
+	}
+
+	private void disableWhitelistButtonIfNothingSelected() {
+		whitelistButton.setDisable(warnings.filtered(w -> w.isSelected()).isEmpty());
 	}
 
 	public void setStage(Stage stage) {
 		this.stage = stage;
+		stage.showingProperty().addListener(new WeakChangeListener<>(stageVisibilityChangeListener));
+	}
+
+	public void setVault(Vault vault) {
+		this.vault = vault;
+	}
+
+	private class Warning {
+
+		private final ReadOnlyStringWrapper name = new ReadOnlyStringWrapper();
+		private final BooleanProperty selected = new SimpleBooleanProperty(false);
+
+		public Warning(String name) {
+			this.name.set(name);
+			this.selectedProperty().addListener(change -> {
+				disableWhitelistButtonIfNothingSelected();
+			});
+		}
+
+		public String getName() {
+			return name.get();
+		}
+
+		public BooleanProperty selectedProperty() {
+			return selected;
+		}
+
+		public boolean isSelected() {
+			return selected.get();
+		}
+
 	}
 
 }

main/ui/src/main/java/org/cryptomator/ui/controllers/MainController.java

@@ -13,25 +13,21 @@ import java.io.IOException;
 import java.net.URL;
 import java.nio.file.Files;
 import java.nio.file.Path;
-import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
 import java.util.ResourceBundle;
-import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.stream.Collectors;
 
 import javafx.application.Platform;
 import javafx.collections.FXCollections;
 import javafx.collections.ListChangeListener;
 import javafx.collections.ObservableList;
-import javafx.collections.SetChangeListener;
 import javafx.event.ActionEvent;
 import javafx.fxml.FXML;
 import javafx.fxml.FXMLLoader;
 import javafx.fxml.Initializable;
 import javafx.geometry.Side;
 import javafx.scene.Parent;
-import javafx.scene.Scene;
 import javafx.scene.control.ContextMenu;
 import javafx.scene.control.ListCell;
 import javafx.scene.control.ListView;
@@ -51,8 +47,6 @@ import org.cryptomator.ui.controls.DirectoryListCell;
 import org.cryptomator.ui.model.Vault;
 import org.cryptomator.ui.model.VaultFactory;
 import org.cryptomator.ui.settings.Settings;
-import org.cryptomator.ui.util.ActiveWindowStyleSupport;
-import org.cryptomator.ui.util.ObservableSetAggregator;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -85,9 +79,6 @@ public class MainController implements Initializable, InitializationListener, Un
 	private final ControllerFactory controllerFactory;
 	private final Settings settings;
 	private final VaultFactory vaultFactoy;
-	private final ObservableList<String> aggregatedMacWarnings;
-	private final SetChangeListener<String> macWarningsAggregator;
-	private final AtomicBoolean macWarningsWindowVisible;
 
 	private ResourceBundle rb;
 
@@ -97,9 +88,6 @@ public class MainController implements Initializable, InitializationListener, Un
 		this.controllerFactory = controllerFactory;
 		this.settings = settings;
 		this.vaultFactoy = vaultFactoy;
-		this.aggregatedMacWarnings = FXCollections.observableList(new ArrayList<>());
-		this.macWarningsAggregator = new ObservableSetAggregator<>(this.aggregatedMacWarnings);
-		this.macWarningsWindowVisible = new AtomicBoolean();
 	}
 
 	@Override
@@ -110,8 +98,6 @@ public class MainController implements Initializable, InitializationListener, Un
 		vaultList.setItems(items);
 		vaultList.setCellFactory(this::createDirecoryListCell);
 		vaultList.getSelectionModel().getSelectedItems().addListener(this::selectedVaultDidChange);
-
-		aggregatedMacWarnings.addListener(this::macWarningsDidChange);
 	}
 
 	@FXML
@@ -233,12 +219,6 @@ public class MainController implements Initializable, InitializationListener, Un
 		showChangePasswordView(selectedVault);
 	}
 
-	private void macWarningsDidChange(ListChangeListener.Change<? extends String> change) {
-		if (aggregatedMacWarnings.size() > 0) {
-			Platform.runLater(this::showMacWarningsWindow);
-		}
-	}
-
 	// ****************************************
 	// Subcontroller for right panel
 	// ****************************************
@@ -293,7 +273,6 @@ public class MainController implements Initializable, InitializationListener, Un
 
 	@Override
 	public void didUnlock(UnlockController ctrl) {
-		ctrl.getVault().getNamesOfResourcesWithInvalidMac().addListener(this.macWarningsAggregator);
 		showUnlockedView(ctrl.getVault());
 		Platform.setImplicitExit(false);
 	}
@@ -306,9 +285,8 @@ public class MainController implements Initializable, InitializationListener, Un
 
 	@Override
 	public void didLock(UnlockedController ctrl) {
-		ctrl.getVault().getNamesOfResourcesWithInvalidMac().removeListener(this.macWarningsAggregator);
 		showUnlockView(ctrl.getVault());
-		if (getUnlockedDirectories().isEmpty()) {
+		if (getUnlockedVaults().isEmpty()) {
 			Platform.setImplicitExit(true);
 		}
 	}
@@ -324,45 +302,14 @@ public class MainController implements Initializable, InitializationListener, Un
 		showUnlockView(ctrl.getVault());
 	}
 
-	private void showMacWarningsWindow() {
-		if (macWarningsWindowVisible.getAndSet(true) == false) {
-			try {
-				final FXMLLoader loader = new FXMLLoader(getClass().getResource("/fxml/mac_warnings.fxml"), rb);
-				loader.setControllerFactory(controllerFactory);
-
-				final Parent root = loader.load();
-				final Stage stage = new Stage();
-				stage.setTitle(rb.getString("macWarnings.windowTitle"));
-				stage.setScene(new Scene(root));
-				stage.sizeToScene();
-				stage.setResizable(false);
-				stage.setOnHidden(this::onHideMacWarningsWindow);
-				ActiveWindowStyleSupport.startObservingFocus(stage);
-
-				final MacWarningsController ctrl = loader.getController();
-				ctrl.setMacWarnings(this.aggregatedMacWarnings);
-				ctrl.setStage(stage);
-
-				stage.show();
-			} catch (IOException e) {
-				throw new IllegalStateException("Failed to load fxml file.", e);
-			}
-		}
-	}
-
-	private void onHideMacWarningsWindow(WindowEvent event) {
-		macWarningsWindowVisible.set(false);
-		aggregatedMacWarnings.clear();
-	}
-
 	/* Convenience */
 
-	public Collection<Vault> getDirectories() {
+	public Collection<Vault> getVaults() {
 		return vaultList.getItems();
 	}
 
-	public Collection<Vault> getUnlockedDirectories() {
-		return getDirectories().stream().filter(d -> d.isUnlocked()).collect(Collectors.toSet());
+	public Collection<Vault> getUnlockedVaults() {
+		return getVaults().stream().filter(d -> d.isUnlocked()).collect(Collectors.toSet());
 	}
 
 	/* public Getter/Setter */

main/ui/src/main/java/org/cryptomator/ui/controllers/UnlockController.java

@@ -35,7 +35,6 @@ import javafx.scene.text.Text;
 import javax.security.auth.DestroyFailedException;
 
 import org.apache.commons.lang3.CharUtils;
-import org.cryptomator.crypto.exceptions.DecryptFailedException;
 import org.cryptomator.crypto.exceptions.UnsupportedKeyLengthException;
 import org.cryptomator.crypto.exceptions.UnsupportedVaultException;
 import org.cryptomator.crypto.exceptions.WrongPasswordException;
@@ -134,7 +133,7 @@ public class UnlockController implements Initializable {
 			vault.setUnlocked(true);
 			final Future<Boolean> futureMount = exec.submit(() -> vault.mount());
 			FXThreads.runOnMainThreadWhenFinished(exec, futureMount, this::unlockAndMountFinished);
-		} catch (DecryptFailedException | IOException ex) {
+		} catch (IOException ex) {
 			setControlsDisabled(false);
 			progressIndicator.setVisible(false);
 			messageText.setText(rb.getString("unlock.errorMessage.decryptionFailed"));
@@ -178,6 +177,7 @@ public class UnlockController implements Initializable {
 		setControlsDisabled(false);
 		if (vault.isUnlocked() && !mountSuccess) {
 			vault.stopServer();
+			vault.setUnlocked(false);
 		}
 		if (mountSuccess && listener != null) {
 			listener.didUnlock(this);

main/ui/src/main/java/org/cryptomator/ui/controllers/UnlockedController.java

@@ -8,31 +8,45 @@
  ******************************************************************************/
 package org.cryptomator.ui.controllers;
 
+import java.io.IOException;
 import java.net.URL;
 import java.util.ResourceBundle;
 
 import javafx.animation.Animation;
 import javafx.animation.KeyFrame;
 import javafx.animation.Timeline;
+import javafx.application.Platform;
+import javafx.collections.ListChangeListener;
 import javafx.event.ActionEvent;
 import javafx.event.EventHandler;
 import javafx.fxml.FXML;
+import javafx.fxml.FXMLLoader;
 import javafx.fxml.Initializable;
+import javafx.scene.Parent;
+import javafx.scene.Scene;
 import javafx.scene.chart.LineChart;
 import javafx.scene.chart.NumberAxis;
 import javafx.scene.chart.XYChart.Data;
 import javafx.scene.chart.XYChart.Series;
 import javafx.scene.control.Label;
+import javafx.stage.Stage;
 import javafx.util.Duration;
 
 import org.cryptomator.crypto.CryptorIOSampling;
+import org.cryptomator.ui.MainModule.ControllerFactory;
 import org.cryptomator.ui.model.Vault;
+import org.cryptomator.ui.util.ActiveWindowStyleSupport;
 import org.cryptomator.ui.util.mount.CommandFailedException;
 
+import com.google.inject.Inject;
+
 public class UnlockedController implements Initializable {
 
 	private static final int IO_SAMPLING_STEPS = 100;
 	private static final double IO_SAMPLING_INTERVAL = 0.25;
+	private final ControllerFactory controllerFactory;
+	private final Stage macWarningWindow = new Stage();
+	private MacWarningsController macWarningCtrl;
 	private LockListener listener;
 	private Vault vault;
 	private Timeline ioAnimation;
@@ -48,9 +62,30 @@ public class UnlockedController implements Initializable {
 
 	private ResourceBundle rb;
 
+	@Inject
+	public UnlockedController(ControllerFactory controllerFactory) {
+		this.controllerFactory = controllerFactory;
+	}
+
 	@Override
 	public void initialize(URL url, ResourceBundle rb) {
 		this.rb = rb;
+
+		try {
+			final FXMLLoader loader = new FXMLLoader(getClass().getResource("/fxml/mac_warnings.fxml"), rb);
+			loader.setControllerFactory(controllerFactory);
+
+			final Parent root = loader.load();
+			macWarningWindow.setScene(new Scene(root));
+			macWarningWindow.sizeToScene();
+			macWarningWindow.setResizable(false);
+			ActiveWindowStyleSupport.startObservingFocus(macWarningWindow);
+
+			macWarningCtrl = loader.getController();
+			macWarningCtrl.setStage(macWarningWindow);
+		} catch (IOException e) {
+			throw new IllegalStateException("Failed to load fxml file.", e);
+		}
 	}
 
 	@FXML
@@ -68,6 +103,22 @@ public class UnlockedController implements Initializable {
 		}
 	}
 
+	// ****************************************
+	// MAC Auth Warnings
+	// ****************************************
+
+	private void macWarningsDidChange(ListChangeListener.Change<? extends String> change) {
+		if (change.getList().size() > 0) {
+			Platform.runLater(() -> {
+				macWarningWindow.show();
+			});
+		} else {
+			Platform.runLater(() -> {
+				macWarningWindow.hide();
+			});
+		}
+	}
+
 	// ****************************************
 	// IO Graph
 	// ****************************************
@@ -128,11 +179,22 @@ public class UnlockedController implements Initializable {
 		return vault;
 	}
 
-	public void setVault(Vault directory) {
-		this.vault = directory;
+	public void setVault(Vault vault) {
+		this.vault = vault;
+		macWarningCtrl.setVault(vault);
 
-		if (directory.getCryptor() instanceof CryptorIOSampling) {
-			startIoSampling((CryptorIOSampling) directory.getCryptor());
+		// listen to MAC warnings as long as this vault is unlocked:
+		final ListChangeListener<String> macWarningsListener = this::macWarningsDidChange;
+		vault.getNamesOfResourcesWithInvalidMac().addListener(macWarningsListener);
+		vault.unlockedProperty().addListener((observable, oldValue, newValue) -> {
+			if (Boolean.FALSE.equals(newValue)) {
+				vault.getNamesOfResourcesWithInvalidMac().removeListener(macWarningsListener);
+			}
+		});
+
+		// sample crypto-throughput:
+		if (vault.getCryptor() instanceof CryptorIOSampling) {
+			startIoSampling((CryptorIOSampling) vault.getCryptor());
 		} else {
 			ioGraph.setVisible(false);
 		}

main/ui/src/main/java/org/cryptomator/ui/model/Vault.java

@@ -6,12 +6,14 @@ import java.nio.file.Files;
 import java.nio.file.Path;
 import java.text.Normalizer;
 import java.text.Normalizer.Form;
+import java.util.HashSet;
 import java.util.Optional;
+import java.util.Set;
 
 import javafx.beans.property.ObjectProperty;
 import javafx.beans.property.SimpleObjectProperty;
 import javafx.collections.FXCollections;
-import javafx.collections.ObservableSet;
+import javafx.collections.ObservableList;
 
 import javax.security.auth.DestroyFailedException;
 
@@ -43,7 +45,8 @@ public class Vault implements Serializable {
 	private final WebDavMounter mounter;
 	private final DeferredCloser closer;
 	private final ObjectProperty<Boolean> unlocked = new SimpleObjectProperty<Boolean>(this, "unlocked", Boolean.FALSE);
-	private final ObservableSet<String> namesOfResourcesWithInvalidMac = FXThreads.observableSetOnMainThread(FXCollections.observableSet());
+	private final ObservableList<String> namesOfResourcesWithInvalidMac = FXThreads.observableListOnMainThread(FXCollections.observableArrayList());
+	private final Set<String> whitelistedResourcesWithInvalidMac = new HashSet<>();
 
 	private String mountName;
 	private DeferredClosable<ServletLifeCycleAdapter> webDavServlet = DeferredClosable.empty();
@@ -77,11 +80,12 @@ public class Vault implements Serializable {
 
 	public synchronized boolean startServer() {
 		namesOfResourcesWithInvalidMac.clear();
+		whitelistedResourcesWithInvalidMac.clear();
 		Optional<ServletLifeCycleAdapter> o = webDavServlet.get();
 		if (o.isPresent() && o.get().isRunning()) {
 			return false;
 		}
-		ServletLifeCycleAdapter servlet = server.createServlet(path, cryptor, namesOfResourcesWithInvalidMac, mountName);
+		ServletLifeCycleAdapter servlet = server.createServlet(path, cryptor, namesOfResourcesWithInvalidMac, whitelistedResourcesWithInvalidMac, mountName);
 		if (servlet.start()) {
 			webDavServlet = closer.closeLater(servlet);
 			return true;
@@ -101,7 +105,7 @@ public class Vault implements Serializable {
 		} catch (DestroyFailedException e) {
 			LOG.error("Destruction of cryptor throw an exception.", e);
 		}
-		setUnlocked(false);
+		whitelistedResourcesWithInvalidMac.clear();
 		namesOfResourcesWithInvalidMac.clear();
 	}
 
@@ -160,10 +164,14 @@ public class Vault implements Serializable {
 		return mountName;
 	}
 
-	public ObservableSet<String> getNamesOfResourcesWithInvalidMac() {
+	public ObservableList<String> getNamesOfResourcesWithInvalidMac() {
 		return namesOfResourcesWithInvalidMac;
 	}
 
+	public Set<String> getWhitelistedResourcesWithInvalidMac() {
+		return whitelistedResourcesWithInvalidMac;
+	}
+
 	/**
 	 * Tries to form a similar string using the regular latin alphabet.
 	 * 

main/ui/src/main/java/org/cryptomator/ui/util/ActiveWindowStyleSupport.java

@@ -2,7 +2,6 @@ package org.cryptomator.ui.util;
 
 import javafx.beans.value.ChangeListener;
 import javafx.beans.value.ObservableValue;
-import javafx.beans.value.WeakChangeListener;
 import javafx.stage.Window;
 
 public class ActiveWindowStyleSupport implements ChangeListener<Boolean> {
@@ -18,9 +17,8 @@ public class ActiveWindowStyleSupport implements ChangeListener<Boolean> {
 	}
 
 	/**
-	 * Creates and registers a listener on the given window, that will add the class {@value #ACTIVE_WINDOW_STYLE_CLASS} to the scenes root
-	 * element, if the window is active. Otherwise {@value #INACTIVE_WINDOW_STYLE_CLASS} will be added. Allows CSS rules to be defined
-	 * depending on the window's focus.<br/>
+	 * Creates and registers a listener on the given window, that will add the class {@value #ACTIVE_WINDOW_STYLE_CLASS} to the scenes root element, if the window is active. Otherwise
+	 * {@value #INACTIVE_WINDOW_STYLE_CLASS} will be added. Allows CSS rules to be defined depending on the window's focus.<br/>
 	 * <br/>
 	 * Example:<br/>
 	 * <code>
@@ -32,7 +30,7 @@ public class ActiveWindowStyleSupport implements ChangeListener<Boolean> {
 	 * @return The observer
 	 */
 	public static ChangeListener<Boolean> startObservingFocus(final Window window) {
-		final ChangeListener<Boolean> observer = new WeakChangeListener<Boolean>(new ActiveWindowStyleSupport(window));
+		final ChangeListener<Boolean> observer = new ActiveWindowStyleSupport(window);
 		window.focusedProperty().addListener(observer);
 		return observer;
 	}

main/ui/src/main/java/org/cryptomator/ui/util/FXThreads.java

@@ -15,6 +15,7 @@ import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Future;
 
 import javafx.application.Platform;
+import javafx.collections.ObservableList;
 import javafx.collections.ObservableSet;
 
 /**
@@ -53,8 +54,7 @@ public final class FXThreads {
 	};
 
 	/**
-	 * Waits for the given task to complete and notifies the given successCallback. If an exception occurs, the callback will never be
-	 * called. If you are interested in the exception, use
+	 * Waits for the given task to complete and notifies the given successCallback. If an exception occurs, the callback will never be called. If you are interested in the exception, use
 	 * {@link #runOnMainThreadWhenFinished(ExecutorService, Future, CallbackWhenTaskFinished, CallbackWhenTaskFailed)} instead.
 	 * 
 	 * <pre>
@@ -74,8 +74,7 @@ public final class FXThreads {
 	}
 
 	/**
-	 * Waits for the given task to complete and notifies the given successCallback. If an exception occurs, the callback will never be
-	 * called. If you are interested in the exception, use
+	 * Waits for the given task to complete and notifies the given successCallback. If an exception occurs, the callback will never be called. If you are interested in the exception, use
 	 * {@link #runOnMainThreadWhenFinished(ExecutorService, Future, CallbackWhenTaskFinished, CallbackWhenTaskFailed)} instead.
 	 * 
 	 * <pre>
@@ -123,4 +122,8 @@ public final class FXThreads {
 		return new ObservableSetOnMainThread<E>(set);
 	}
 
+	public static <E> ObservableList<E> observableListOnMainThread(ObservableList<E> list) {
+		return new ObservableListOnMainThread<E>(list);
+	}
+
 }

main/ui/src/main/java/org/cryptomator/ui/util/ObservableListOnMainThread.java

@@ -0,0 +1,276 @@
+package org.cryptomator.ui.util;
+
+import java.util.Collection;
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.List;
+import java.util.ListIterator;
+
+import javafx.application.Platform;
+import javafx.beans.InvalidationListener;
+import javafx.beans.Observable;
+import javafx.collections.ListChangeListener;
+import javafx.collections.ListChangeListener.Change;
+import javafx.collections.ObservableList;
+
+import com.google.common.collect.ImmutableList;
+
+class ObservableListOnMainThread<E> implements ObservableList<E> {
+
+	private final ObservableList<E> list;
+	private final Collection<InvalidationListener> invalidationListeners;
+	private final Collection<ListChangeListener<? super E>> listChangeListeners;
+
+	public ObservableListOnMainThread(ObservableList<E> list) {
+		this.list = list;
+		this.invalidationListeners = new HashSet<>();
+		this.listChangeListeners = new HashSet<>();
+		this.list.addListener(this::invalidated);
+		this.list.addListener(this::onChanged);
+	}
+
+	@Override
+	public int size() {
+		return list.size();
+	}
+
+	@Override
+	public boolean isEmpty() {
+		return list.isEmpty();
+	}
+
+	@Override
+	public boolean contains(Object o) {
+		return list.contains(o);
+	}
+
+	@Override
+	public Iterator<E> iterator() {
+		return list.iterator();
+	}
+
+	@Override
+	public Object[] toArray() {
+		return list.toArray();
+	}
+
+	@Override
+	public <T> T[] toArray(T[] a) {
+		return list.toArray(a);
+	}
+
+	@Override
+	public boolean add(E e) {
+		return list.add(e);
+	}
+
+	@Override
+	public boolean remove(Object o) {
+		return list.remove(o);
+	}
+
+	@Override
+	public boolean containsAll(Collection<?> c) {
+		return list.containsAll(c);
+	}
+
+	@Override
+	public boolean addAll(Collection<? extends E> c) {
+		return list.addAll(c);
+	}
+
+	@Override
+	public boolean addAll(int index, Collection<? extends E> c) {
+		return list.addAll(index, c);
+	}
+
+	@Override
+	public boolean removeAll(Collection<?> c) {
+		return list.removeAll(c);
+	}
+
+	@Override
+	public boolean retainAll(Collection<?> c) {
+		return list.retainAll(c);
+	}
+
+	@Override
+	public void clear() {
+		list.clear();
+	}
+
+	@Override
+	public E get(int index) {
+		return list.get(index);
+	}
+
+	@Override
+	public E set(int index, E element) {
+		return list.set(index, element);
+	}
+
+	@Override
+	public void add(int index, E element) {
+		list.add(index, element);
+	}
+
+	@Override
+	public E remove(int index) {
+		return list.remove(index);
+	}
+
+	@Override
+	public int indexOf(Object o) {
+		return list.indexOf(o);
+	}
+
+	@Override
+	public int lastIndexOf(Object o) {
+		return list.lastIndexOf(o);
+	}
+
+	@Override
+	public ListIterator<E> listIterator() {
+		return list.listIterator();
+	}
+
+	@Override
+	public ListIterator<E> listIterator(int index) {
+		return list.listIterator(index);
+	}
+
+	@Override
+	public List<E> subList(int fromIndex, int toIndex) {
+		return list.subList(fromIndex, toIndex);
+	}
+
+	@Override
+	public boolean addAll(@SuppressWarnings("unchecked") E... elements) {
+		return list.addAll(elements);
+	}
+
+	@Override
+	public boolean setAll(@SuppressWarnings("unchecked") E... elements) {
+		return list.addAll(elements);
+	}
+
+	@Override
+	public boolean setAll(Collection<? extends E> col) {
+		return list.setAll(col);
+	}
+
+	@Override
+	public boolean removeAll(@SuppressWarnings("unchecked") E... elements) {
+		return list.removeAll(elements);
+	}
+
+	@Override
+	public boolean retainAll(@SuppressWarnings("unchecked") E... elements) {
+		return list.retainAll(elements);
+	}
+
+	@Override
+	public void remove(int from, int to) {
+		list.remove(from, to);
+	}
+
+	private void invalidated(Observable observable) {
+		final Collection<InvalidationListener> listeners = ImmutableList.copyOf(invalidationListeners);
+		Platform.runLater(() -> {
+			for (InvalidationListener listener : listeners) {
+				listener.invalidated(this);
+			}
+		});
+	}
+
+	@Override
+	public void addListener(InvalidationListener listener) {
+		invalidationListeners.add(listener);
+	}
+
+	@Override
+	public void removeListener(InvalidationListener listener) {
+		invalidationListeners.remove(listener);
+	}
+
+	private void onChanged(Change<? extends E> change) {
+		final Change<? extends E> c = new ListChange(change);
+		final Collection<ListChangeListener<? super E>> listeners = ImmutableList.copyOf(listChangeListeners);
+		Platform.runLater(() -> {
+			for (ListChangeListener<? super E> listener : listeners) {
+				listener.onChanged(c);
+			}
+		});
+	}
+
+	@Override
+	public void addListener(ListChangeListener<? super E> listener) {
+		listChangeListeners.add(listener);
+	}
+
+	@Override
+	public void removeListener(ListChangeListener<? super E> listener) {
+		listChangeListeners.remove(listener);
+	}
+
+	private class ListChange extends ListChangeListener.Change<E> {
+
+		private final Change<? extends E> originalChange;
+
+		public ListChange(Change<? extends E> change) {
+			super(ObservableListOnMainThread.this);
+			this.originalChange = change;
+		}
+
+		@Override
+		public boolean wasAdded() {
+			return originalChange.wasAdded();
+		}
+
+		@Override
+		public boolean wasRemoved() {
+			return originalChange.wasRemoved();
+		}
+
+		@Override
+		public boolean next() {
+			return originalChange.next();
+		}
+
+		@Override
+		public void reset() {
+			originalChange.reset();
+		}
+
+		@Override
+		public int getFrom() {
+			return originalChange.getFrom();
+		}
+
+		@Override
+		public int getTo() {
+			return originalChange.getTo();
+		}
+
+		@Override
+		@SuppressWarnings("unchecked")
+		public List<E> getRemoved() {
+			return (List<E>) originalChange.getRemoved();
+		}
+
+		@Override
+		protected int[] getPermutation() {
+			if (originalChange.wasPermutated()) {
+				int[] permutations = new int[originalChange.getTo() - originalChange.getFrom()];
+				for (int i = 0; i < permutations.length; i++) {
+					permutations[i] = originalChange.getPermutation(i);
+				}
+				return permutations;
+			} else {
+				return new int[0];
+			}
+		}
+
+	}
+
+}

main/ui/src/main/java/org/cryptomator/ui/util/ObservableSetAggregator.java

@@ -1,44 +0,0 @@
-/*******************************************************************************
- * Copyright (c) 2014 cryptomator.org
- * This file is licensed under the terms of the MIT license.
- * See the LICENSE.txt file for more info.
- * 
- * Contributors:
- *    Sebastian Stenzel - initial implementation
- ******************************************************************************/
-package org.cryptomator.ui.util;
-
-import java.util.Collection;
-
-import javafx.collections.ObservableSet;
-import javafx.collections.SetChangeListener;
-
-/**
- * From the moment on, this aggregator is added as an observer to one or many {@link ObservableSet}s, change-events will be passed through
- * to the given aggregation.
- */
-public class ObservableSetAggregator<E> implements SetChangeListener<E> {
-
-	private final Collection<E> aggregation;
-
-	/**
-	 * @param aggregation Set to which elements from observed subsets shall be added.
-	 */
-	public ObservableSetAggregator(final Collection<E> aggregation) {
-		this.aggregation = aggregation;
-	}
-
-	@Override
-	public void onChanged(Change<? extends E> change) {
-		if (change.getSet() == aggregation) {
-			// break cycle if aggregator observes aggregation
-			return;
-		}
-		if (change.wasAdded()) {
-			aggregation.add(change.getElementAdded());
-		} else if (change.wasRemoved()) {
-			aggregation.remove(change.getElementRemoved());
-		}
-	}
-
-}

main/ui/src/main/java/org/cryptomator/ui/util/ObservableSetOnMainThread.java

@@ -11,6 +11,8 @@ import javafx.collections.ObservableSet;
 import javafx.collections.SetChangeListener;
 import javafx.collections.SetChangeListener.Change;
 
+import com.google.common.collect.ImmutableList;
+
 class ObservableSetOnMainThread<E> implements ObservableSet<E> {
 
 	private final ObservableSet<E> set;
@@ -91,8 +93,9 @@ class ObservableSetOnMainThread<E> implements ObservableSet<E> {
 	}
 
 	private void invalidated(Observable observable) {
+		final Collection<InvalidationListener> listeners = ImmutableList.copyOf(invalidationListeners);
 		Platform.runLater(() -> {
-			for (InvalidationListener listener : invalidationListeners) {
+			for (InvalidationListener listener : listeners) {
 				listener.invalidated(this);
 			}
 		});
@@ -110,8 +113,9 @@ class ObservableSetOnMainThread<E> implements ObservableSet<E> {
 
 	private void onChanged(Change<? extends E> change) {
 		final Change<? extends E> c = new SetChange(this, change.getElementAdded(), change.getElementRemoved());
+		final Collection<SetChangeListener<? super E>> listeners = ImmutableList.copyOf(setChangeListeners);
 		Platform.runLater(() -> {
-			for (SetChangeListener<? super E> listener : setChangeListeners) {
+			for (SetChangeListener<? super E> listener : listeners) {
 				listener.onChanged(c);
 			}
 		});

main/ui/src/main/java/org/cryptomator/ui/util/mount/WindowsWebDavMounter.java

@@ -30,7 +30,7 @@ import org.cryptomator.ui.util.command.Script;
 final class WindowsWebDavMounter implements WebDavMounterStrategy {
 
 	private static final Pattern WIN_MOUNT_DRIVELETTER_PATTERN = Pattern.compile("\\s*([A-Z]:)\\s*");
-	private static final int MAX_MOUNT_ATTEMPTS = 5;
+	private static final int MAX_MOUNT_ATTEMPTS = 8;
 
 	@Override
 	public boolean shouldWork() {
@@ -39,30 +39,26 @@ final class WindowsWebDavMounter implements WebDavMounterStrategy {
 
 	@Override
 	public void warmUp(int serverPort) {
-//		try {
-//			final Script mountScript = fromLines("net use * \\\\localhost@%DAV_PORT%\\DavWWWRoot\\bill-gates-mom-uses-goto /persistent:no");
-//			mountScript.addEnv("DAV_PORT", String.valueOf(serverPort));
-//			mountScript.execute(1, TimeUnit.SECONDS);
-//		} catch (CommandFailedException e) {
-//            // will most certainly throw an exception, because this is a fake WebDav path. But now windows has some DNS things cached :)
-//		}
+		// no-op
 	}
 
 	@Override
 	public WebDavMount mount(URI uri, String name) throws CommandFailedException {
 		CommandResult mountResult;
 		try {
-			final Script mountScript = fromLines("net use * \\\\0--1.ipv6-literal.net@%DAV_PORT%\\DavWWWRoot%DAV_UNC_PATH% /persistent:no");
+			final Script mountScript = fromLines("net use * \\\\localhost@%DAV_PORT%\\DavWWWRoot%DAV_UNC_PATH% /persistent:no");
 			mountScript.addEnv("DAV_PORT", String.valueOf(uri.getPort())).addEnv("DAV_UNC_PATH", uri.getRawPath().replace('/', '\\'));
 			mountResult = mountScript.execute(5, TimeUnit.SECONDS);
 		} catch (CommandFailedException ex) {
-			final Script mountScript = fromLines("net use * \\\\0--1.ipv6-literal.net@%DAV_PORT%\\DavWWWRoot%DAV_UNC_PATH% /persistent:no");
-			mountScript.addEnv("DAV_PORT", String.valueOf(uri.getPort())).addEnv("DAV_UNC_PATH", uri.getRawPath().replace('/', '\\'));
+			final Script localhostMountScript = fromLines("net use * \\\\localhost@%DAV_PORT%\\DavWWWRoot%DAV_UNC_PATH% /persistent:no");
+			localhostMountScript.addEnv("DAV_PORT", String.valueOf(uri.getPort())).addEnv("DAV_UNC_PATH", uri.getRawPath().replace('/', '\\'));
+			final Script ipv6literaltMountScript = fromLines("net use * \\\\0--1.ipv6-literal.net@%DAV_PORT%\\DavWWWRoot%DAV_UNC_PATH% /persistent:no");
+			ipv6literaltMountScript.addEnv("DAV_PORT", String.valueOf(uri.getPort())).addEnv("DAV_UNC_PATH", uri.getRawPath().replace('/', '\\'));
 			final Script proxyBypassScript = fromLines("reg add \"HKCU\\Software\\Microsoft\\Windows\\CurrentVersion\\Internet Settings\" /v \"ProxyOverride\" /d \"<local>;0--1.ipv6-literal.net;0--1.ipv6-literal.net:%DAV_PORT%\" /f");
-	        proxyBypassScript.addEnv("DAV_PORT", String.valueOf(uri.getPort()));
-			mountResult = bypassProxyAndRetryMount(mountScript, proxyBypassScript);
+			proxyBypassScript.addEnv("DAV_PORT", String.valueOf(uri.getPort()));
+			mountResult = bypassProxyAndRetryMount(localhostMountScript, ipv6literaltMountScript, proxyBypassScript);
 		}
-		
+
 		final String driveLetter = getDriveLetter(mountResult.getStdOut());
 		final Script openExplorerScript = fromLines("start explorer.exe " + driveLetter);
 		openExplorerScript.execute();
@@ -77,7 +73,7 @@ final class WindowsWebDavMounter implements WebDavMounterStrategy {
 			}
 		};
 	}
-	
+
 	private boolean isVolumeMounted(String driveLetter) {
 		for (Path path : FileSystems.getDefault().getRootDirectories()) {
 			if (path.toString().startsWith(driveLetter)) {
@@ -86,15 +82,17 @@ final class WindowsWebDavMounter implements WebDavMounterStrategy {
 		}
 		return false;
 	}
-	
-	private CommandResult bypassProxyAndRetryMount(Script mountScript, Script proxyBypassScript) throws CommandFailedException {
+
+	private CommandResult bypassProxyAndRetryMount(Script localhostMountScript, Script ipv6literalMountScript, Script proxyBypassScript) throws CommandFailedException {
 		CommandFailedException latestException = null;
 		for (int i = 0; i < MAX_MOUNT_ATTEMPTS; i++) {
 			try {
 				// wait a moment before next attempt
 				Thread.sleep(5000);
 				proxyBypassScript.execute();
-				return mountScript.execute(5, TimeUnit.SECONDS);
+				// alternate localhost and 0--1.ipv6literal.net
+				final Script mountScript = (i % 2 == 0) ? localhostMountScript : ipv6literalMountScript;
+				return mountScript.execute(3, TimeUnit.SECONDS);
 			} catch (CommandFailedException ex) {
 				latestException = ex;
 			} catch (InterruptedException ex) {

main/ui/src/main/resources/fxml/mac_warnings.fxml

@@ -24,7 +24,7 @@
 		<ListView fx:id="warningsList" VBox.vgrow="ALWAYS" focusTraversable="false" />
 		<HBox alignment="CENTER_RIGHT" spacing="12.0">
 			<children>
-				<Button text="%macWarnings.dismissButton" prefWidth="200.0" onAction="#didClickDismissButton" focusTraversable="false"/>
+				<Button fx:id="whitelistButton" text="%macWarnings.whitelistButton" prefWidth="200.0" onAction="#didClickWhitelistButton" focusTraversable="false"/>
 				<Button text="%macWarnings.moreInformationButton" defaultButton="true" prefWidth="200.0" onAction="#didClickMoreInformationButton" focusTraversable="false"/>
 			</children>
 		</HBox>

main/ui/src/main/resources/localization.properties

@@ -56,10 +56,10 @@ unlocked.label.unmountFailed=Ejecting drive failed.
 unlocked.ioGraph.yAxis.label=Throughput (MiB/s)
 
 # mac_warnings.fxml
-macWarnings.windowTitle=Danger - MAC authentication failed
+macWarnings.windowTitle=Danger - Corrupted file in %s
 macWarnings.message=Cryptomator detected potentially malicious corruptions in the following files:
 macWarnings.moreInformationButton=Learn more
-macWarnings.dismissButton=I promise to be careful
+macWarnings.whitelistButton=Decrypt selected anyway
 
 # tray icon
 tray.menu.open=Open