fixed serious bugs in stream encrypt/decrypt code

histream-core/src/main/java/de/sekmi/histream/crypto/DecryptingInputStream.java

@@ -26,7 +26,7 @@ public class DecryptingInputStream implements ReadableByteChannel {
 	public DecryptingInputStream(ReadableByteChannel in, String symmetricAlgorithm, int symmetricKeysize, String asymmetricCipher, Key asymmetricKey) throws GeneralSecurityException, IOException{
 		// use buffer
 		endOfStream = false;
-		buffer = ByteBuffer.allocate(1024*10);
+		buffer = ByteBuffer.allocate(1024*8);
 
 		in.read(buffer);
 		buffer.flip();
@@ -64,7 +64,7 @@ public class DecryptingInputStream implements ReadableByteChannel {
 	@Override
 	public int read(ByteBuffer dst) throws IOException {
 		if( endOfStream )
-			return 0; // nothing to do
+			return -1; // nothing to do
 		
 		int bytesRead=0;
 		if( buffer.hasRemaining() ){
@@ -74,9 +74,11 @@ public class DecryptingInputStream implements ReadableByteChannel {
 		try {
 			if( bytesRead == -1 ){
 				endOfStream = true;
-				return cipher.doFinal(buffer, dst);
+				bytesRead = cipher.doFinal(buffer, dst);
+				return bytesRead;
 			}else{
-				return cipher.update(buffer, dst);
+				bytesRead = cipher.update(buffer, dst);
+				return bytesRead;
 			}
 		} catch (ShortBufferException | IllegalBlockSizeException | BadPaddingException e) {
 			throw new IOException(e);

histream-core/src/main/java/de/sekmi/histream/crypto/EncryptingOutputStream.java

@@ -13,6 +13,13 @@ import javax.crypto.KeyGenerator;
 import javax.crypto.SecretKey;
 import javax.crypto.ShortBufferException;
 
+/**
+ * Wraps a WritableByteChannel with encryption. 
+ * Closing the EncryptionOutputStream will close the underlying WritableByteChannel
+
+ * @author Raphael
+ *
+ */
 public class EncryptingOutputStream implements WritableByteChannel{
 	public static final int Version = 1;
 	private Cipher cipher;
@@ -58,9 +65,11 @@ public class EncryptingOutputStream implements WritableByteChannel{
 	}
 	@Override
 	public void close() throws IOException {
+		buffer.flip();
 		if( buffer.hasRemaining() ){
 			out.write(buffer);
 		}
+		buffer.compact();
 		try {
 			out.write(ByteBuffer.wrap(cipher.doFinal()));
 		} catch (IllegalBlockSizeException | BadPaddingException e) {
@@ -70,13 +79,19 @@ public class EncryptingOutputStream implements WritableByteChannel{
 	}
 	@Override
 	public int write(ByteBuffer src) throws IOException {
+		int processed = 0;
 		try {
+			int pos = src.position();
 			cipher.update(src, buffer);
+			processed = src.position() - pos;
 		} catch (ShortBufferException e) {
 			throw new IOException(e);
-		} finally {
+		}
+		if( buffer.position() != 0 ){
 			buffer.flip();
+			out.write(buffer);
+			buffer.compact();
 		}
-		return out.write(buffer);
+		return processed;
 	}
 }