com.itextpdf.kernel.crypto.OutputStreamAesEncryption Maven / Gradle / Ivy
/*
This file is part of the iText (R) project.
Copyright (c) 1998-2021 iText Group NV
Authors: Bruno Lowagie, Paulo Soares, et al.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License version 3
as published by the Free Software Foundation with the addition of the
following permission added to Section 15 as permitted in Section 7(a):
FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY
ITEXT GROUP. ITEXT GROUP DISCLAIMS THE WARRANTY OF NON INFRINGEMENT
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or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License
along with this program; if not, see http://www.gnu.org/licenses or write to
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Boston, MA, 02110-1301 USA, or download the license from the following URL:
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The interactive user interfaces in modified source and object code versions
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Section 5 of the GNU Affero General Public License.
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a covered work must retain the producer line in every PDF that is created
or manipulated using iText.
You can be released from the requirements of the license by purchasing
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develop commercial activities involving the iText software without
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These activities include: offering paid services to customers as an ASP,
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*/
package com.itextpdf.kernel.crypto;
import com.itextpdf.kernel.PdfException;
import java.io.IOException;
public class OutputStreamAesEncryption extends OutputStreamEncryption {
protected AESCipher cipher;
private boolean finished;
/**
* Creates a new instance of {@link OutputStreamAesEncryption}
* @param out the {@link java.io.OutputStream} instance to be used as the destination for the encrypted content
* @param key the byte array containing the key for encryption
* @param off offset of the key in the byte array
* @param len the length of the key in the byte array
*/
public OutputStreamAesEncryption(java.io.OutputStream out, byte[] key, int off, int len) {
super(out);
byte[] iv = IVGenerator.getIV();
byte[] nkey = new byte[len];
System.arraycopy(key, off, nkey, 0, len);
cipher = new AESCipher(true, nkey, iv);
try {
write(iv);
} catch (IOException e) {
throw new PdfException(PdfException.PdfEncryption, e);
}
}
/**
* Creates a new instance of {@link OutputStreamAesEncryption}
* @param out the {@link java.io.OutputStream} instance to be used as the destination for the encrypted content
* @param key the byte array which is the key for encryption
*/
public OutputStreamAesEncryption(java.io.OutputStream out, byte[] key) {
this(out, key, 0, key.length);
}
/**
* Writes {@code len} bytes from the specified byte array
* starting at offset {@code off} to this output stream.
* The general contract for {@code write(b, off, len)} is that
* some of the bytes in the array {@code b} are written to the
* output stream in order; element {@code b[off]} is the first
* byte written and {@code b[off+len-1]} is the last byte written
* by this operation.
*
* The {@code write} method of {@code OutputStream} calls
* the write method of one argument on each of the bytes to be
* written out. Subclasses are encouraged to override this method and
* provide a more efficient implementation.
*
* If {@code b} is {@code null}, a
* {@code NullPointerException} is thrown.
*
* If {@code off} is negative, or {@code len} is negative, or
* {@code off+len} is greater than the length of the array
* {@code b}, then an IndexOutOfBoundsException is thrown.
*
* @param b the data.
* @param off the start offset in the data.
* @param len the number of bytes to write.
* @throws IOException if an I/O error occurs. In particular,
* an {@code IOException} is thrown if the output
* stream is closed.
*/
public void write(byte[] b, int off, int len) throws IOException {
byte[] b2 = cipher.update(b, off, len);
if (b2 == null || b2.length == 0)
return;
out.write(b2, 0, b2.length);
}
public void finish() {
if (!finished) {
finished = true;
byte[] b = cipher.doFinal();
try {
out.write(b, 0, b.length);
} catch (IOException e) {
throw new PdfException(PdfException.PdfEncryption, e);
}
}
}
}