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package gnu.crypto.keyring; // -*- c-basic-offset: 3 -*-
// ---------------------------------------------------------------------------
// $Id: EncryptedEntry.java,v 1.3 2003/10/23 09:59:41 rsdio Exp $
//
// Copyright (C) 2003 Free Software Foundation, Inc.
//
// This file is part of GNU Crypto.
//
// GNU Crypto is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2, or (at your option)
// any later version.
//
// GNU Crypto 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 for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; see the file COPYING. If not, write to the
//
// Free Software Foundation Inc.,
// 59 Temple Place - Suite 330,
// Boston, MA 02111-1307
// USA
//
// Linking this library statically or dynamically with other modules is
// making a combined work based on this library. Thus, the terms and
// conditions of the GNU General Public License cover the whole
// combination.
//
// As a special exception, the copyright holders of this library give
// you permission to link this library with independent modules to
// produce an executable, regardless of the license terms of these
// independent modules, and to copy and distribute the resulting
// executable under terms of your choice, provided that you also meet,
// for each linked independent module, the terms and conditions of the
// license of that module. An independent module is a module which is
// not derived from or based on this library. If you modify this
// library, you may extend this exception to your version of the
// library, but you are not obligated to do so. If you do not wish to
// do so, delete this exception statement from your version.
//
// ---------------------------------------------------------------------------
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.security.InvalidKeyException;
import java.util.Arrays;
import java.util.Collections;
import java.util.Date;
import java.util.Iterator;
import java.util.HashMap;
import java.util.List;
import gnu.crypto.Registry;
import gnu.crypto.cipher.CipherFactory;
import gnu.crypto.cipher.IBlockCipher;
import gnu.crypto.mode.IMode;
import gnu.crypto.mode.ModeFactory;
import gnu.crypto.pad.IPad;
import gnu.crypto.pad.PadFactory;
import gnu.crypto.pad.WrongPaddingException;
public class EncryptedEntry extends MaskableEnvelopeEntry implements Registry {
// Constants and fields.
// ------------------------------------------------------------------------
public static final int TYPE = 0;
// Constructor.
// ------------------------------------------------------------------------
public EncryptedEntry(String cipher, String mode, Properties properties) {
super(TYPE, properties);
if (cipher == null || mode == null) {
throw new IllegalArgumentException("neither cipher nor mode can be null");
}
properties.put("cipher", cipher);
properties.put("mode", mode);
setMasked(false);
}
private EncryptedEntry() {
setMasked(true);
}
// Class methods.
// ------------------------------------------------------------------------
public static EncryptedEntry decode(DataInputStream in) throws IOException {
EncryptedEntry entry = new EncryptedEntry();
entry.defaultDecode(in);
if (!entry.properties.containsKey("cipher")) {
throw new MalformedKeyringException("no cipher");
}
if (!entry.properties.containsKey("cipher")) {
throw new MalformedKeyringException("no cipher");
}
return entry;
}
// Instance methods.
// ------------------------------------------------------------------------
public void decrypt(byte[] key, byte[] iv)
throws IllegalArgumentException, WrongPaddingException
{
if (!isMasked() || payload == null) {
return;
}
IMode mode = getMode(key, iv, IMode.DECRYPTION);
IPad padding = null;
padding = PadFactory.getInstance("PKCS7");
padding.init(mode.currentBlockSize());
byte[] buf = new byte[payload.length];
int count = 0;
for (int i = 0; i < payload.length; i++) {
mode.update(payload, count, buf, count);
count += mode.currentBlockSize();
}
int padlen = padding.unpad(buf, 0, buf.length);
DataInputStream in =
new DataInputStream(new ByteArrayInputStream(buf, 0, buf.length - padlen));
try {
decodeEnvelope(in);
} catch (IOException ioe) {
throw new IllegalArgumentException("decryption failed");
}
setMasked(false);
payload = null;
}
public void encrypt(byte[] key, byte[] iv) throws IOException {
IMode mode = getMode(key, iv, IMode.ENCRYPTION);
IPad pad = PadFactory.getInstance("PKCS7");
pad.init(mode.currentBlockSize());
ByteArrayOutputStream bout = new ByteArrayOutputStream(1024);
DataOutputStream out2 = new DataOutputStream(bout);
for (Iterator it = entries.iterator(); it.hasNext(); ) {
Entry entry = (Entry) it.next();
entry.encode(out2);
}
byte[] plaintext = bout.toByteArray();
byte[] padding = pad.pad(plaintext, 0, plaintext.length);
payload = new byte[plaintext.length + padding.length];
byte[] lastBlock = new byte[mode.currentBlockSize()];
int l = mode.currentBlockSize() - padding.length;
System.arraycopy(plaintext, plaintext.length - l, lastBlock, 0, l);
System.arraycopy(padding, 0, lastBlock, l, padding.length);
int count = 0;
while (count + mode.currentBlockSize() < plaintext.length) {
mode.update(plaintext, count, payload, count);
count += mode.currentBlockSize();
}
mode.update(lastBlock, 0, payload, count);
}
public void encodePayload() throws IOException {
if (payload == null) {
throw new IOException("not encrypted");
}
}
// Own methods.
// ------------------------------------------------------------------------
private IMode getMode(byte[] key, byte[] iv, int state) {
IBlockCipher cipher = CipherFactory.getInstance(properties.get("cipher"));
if (cipher == null) {
throw new IllegalArgumentException("no such cipher: " + properties.get("cipher"));
}
int blockSize = cipher.defaultBlockSize();
if (properties.containsKey("block-size")) {
try {
blockSize = Integer.parseInt(properties.get("block-size"));
} catch (NumberFormatException nfe) {
throw new IllegalArgumentException("bad block size: " + nfe.getMessage());
}
}
IMode mode = ModeFactory.getInstance(properties.get("mode"), cipher, blockSize);
if (mode == null) {
throw new IllegalArgumentException("no such mode: " + properties.get("mode"));
}
HashMap modeAttr = new HashMap();
modeAttr.put(IMode.KEY_MATERIAL, key);
modeAttr.put(IMode.STATE, new Integer(state));
modeAttr.put(IMode.IV, iv);
try {
mode.init(modeAttr);
} catch (InvalidKeyException ike) {
throw new IllegalArgumentException(ike.toString());
}
return mode;
}
}