- reduced size of chunks, a MAC is calculated for (not final yet)

- faster range requests due to reduced chunk size, thus faster video playback start
- fixed range requests
- making file locks optional (if not supported by file system)

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

@@ -84,7 +84,7 @@ interface AesCryptographicConfiguration {
 	/**
 	 * Number of bytes, a content block over which a MAC is calculated consists of.
 	 */
-	int CONTENT_MAC_BLOCK = 5 * 1024 * 1024;
+	int CONTENT_MAC_BLOCK = 128 * 1024;
 
 	/**
 	 * How to encode the encrypted file names safely. Base32 uses only alphanumeric characters and is case-insensitive.

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

@@ -139,10 +139,10 @@ public class Aes256CryptorTest {
 
 	@Test
 	public void testPartialDecryption() throws IOException, DecryptFailedException, WrongPasswordException, UnsupportedKeyLengthException, EncryptFailedException {
-		// our test plaintext data:
-		final byte[] plaintextData = new byte[524288 * 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 < 524288; i++) {
+		for (int i = 0; i < 2097152; i++) {
 			bbIn.putInt(i);
 		}
 		final InputStream plaintextIn = new ByteArrayInputStream(plaintextData);