net.yapbam.util.CipherOutputStream Maven / Gradle / Ivy
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package net.yapbam.util;
import java.io.*;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
/*
* Copyright (c) 1997, 2007, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/**
* A modified version of the javax.crypto.CipherOutputStream that allows the cipher to be finished
* without closing the underlying stream.
*
A CipherOutputStream is composed of an OutputStream and a Cipher so that
* write() methods first process the data before writing them out to the
* underlying OutputStream. The cipher must be fully initialized before being
* used by a CipherOutputStream.
*
*
* For example, if the cipher is initialized for encryption, the
* CipherOutputStream will attempt to encrypt data before writing out the
* encrypted data.
*
*
* This class adheres strictly to the semantics, especially the failure
* semantics, of its ancestor classes java.io.OutputStream and
* java.io.FilterOutputStream. This class has exactly those methods specified in
* its ancestor classes, and overrides them all. Moreover, this class catches
* all exceptions that are not thrown by its ancestor classes.
*
*
* It is crucial for a programmer using this class not to use methods that are
* not defined or overridden in this class (such as a new method or constructor
* that is later added to one of the super classes), because the design and
* implementation of those methods are unlikely to have considered security
* impact with regard to CipherOutputStream.
*
* @author Jean-Marc Astesana (based on the original work of Li Gong)
* @see java.io.OutputStream
* @see java.io.FilterOutputStream
* @see javax.crypto.Cipher
* @see javax.crypto.CipherInputStream
*
* @since 1.4
* @deprecated
*/
@Deprecated
class CipherOutputStream extends FilterOutputStream { //NOSONAR
// the cipher engine to use to process stream data
private Cipher cipher;
// the underlying output stream
private OutputStream output;
/* the buffer holding one byte of incoming data */
private byte[] ibuffer = new byte[1];
// the buffer holding data ready to be written out
private byte[] obuffer;
/**
*
* Constructs a CipherOutputStream from an OutputStream and a Cipher.
* Note: if the specified output stream or cipher is null, a
* NullPointerException may be thrown later when they are used.
*
* @param os
* the OutputStream object
* @param c
* an initialized Cipher object
*/
public CipherOutputStream(OutputStream os, Cipher c) {
super(os);
output = os;
cipher = c;
}
/**
* Writes the specified byte to this output stream.
*
* @param b
* the byte.
* @exception IOException
* if an I/O error occurs.
* @since JCE1.2
*/
public void write(int b) throws IOException {
ibuffer[0] = (byte) b;
obuffer = cipher.update(ibuffer, 0, 1);
if (obuffer != null) {
output.write(obuffer);
obuffer = null;
}
}
/**
* Writes b.length bytes from the specified byte array to this
* output stream.
*
* The write method of CipherOutputStream calls the
* write method of three arguments with the three arguments
* b, 0, and b.length.
*
* @param b
* the data.
* @exception NullPointerException
* if b is null.
* @exception IOException
* if an I/O error occurs.
* @see javax.crypto.CipherOutputStream#write(byte[], int, int)
* @since JCE1.2
*/
public void write(byte b[]) throws IOException {
write(b, 0, b.length);
}
/**
* Writes len bytes from the specified byte array starting at
* offset off to this output stream.
*
* @param b
* the data.
* @param off
* the start offset in the data.
* @param len
* the number of bytes to write.
* @exception IOException
* if an I/O error occurs.
* @since JCE1.2
*/
public void write(byte b[], int off, int len) throws IOException {
obuffer = cipher.update(b, off, len);
if (obuffer != null) {
output.write(obuffer);
obuffer = null;
}
}
/**
* Flushes this output stream by forcing any buffered output bytes that have
* already been processed by the encapsulated cipher object to be written out.
*
*
* Any bytes buffered by the encapsulated cipher and waiting to be processed
* by it will not be written out. For example, if the encapsulated cipher is a
* block cipher, and the total number of bytes written using one of the
* write methods is less than the cipher's block size, no bytes
* will be written out.
*
* @exception IOException
* if an I/O error occurs.
* @since JCE1.2
*/
public void flush() throws IOException {
if (obuffer != null) {
output.write(obuffer);
obuffer = null;
}
output.flush();
}
/**
* Closes this output stream and releases any system resources associated with
* this stream.
*
* This method invokes the doFinal method of the encapsulated
* cipher object, which causes any bytes buffered by the encapsulated cipher
* to be processed. The result is written out by calling the
* flush method of this output stream.
*
* This method resets the encapsulated cipher object to its initial state and
* calls the close method of the underlying output stream.
*
* @exception IOException
* if an I/O error occurs.
* @since JCE1.2
*/
public void close() throws IOException {
finish();
out.close();
}
public void finish() throws IOException {
try {
obuffer = cipher.doFinal();
} catch (IllegalBlockSizeException e) {
obuffer = null;
} catch (BadPaddingException e) {
obuffer = null;
}
try {
flush();
} catch (IOException ignored) {
}
}
}