| /* ==================================================================== |
| Licensed to the Apache Software Foundation (ASF) under one or more |
| contributor license agreements. See the NOTICE file distributed with |
| this work for additional information regarding copyright ownership. |
| The ASF licenses this file to You under the Apache License, Version 2.0 |
| (the "License"); you may not use this file except in compliance with |
| the License. You may obtain a copy of the License at |
| |
| http://www.apache.org/licenses/LICENSE-2.0 |
| |
| Unless required by applicable law or agreed to in writing, software |
| distributed under the License is distributed on an "AS IS" BASIS, |
| WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| See the License for the specific language governing permissions and |
| limitations under the License. |
| ==================================================================== */ |
| |
| package org.apache.poi.poifs.crypt.cryptoapi; |
| |
| import java.io.IOException; |
| |
| import org.apache.poi.poifs.crypt.*; |
| import org.apache.poi.util.LittleEndianInput; |
| |
| public class CryptoAPIEncryptionInfoBuilder implements EncryptionInfoBuilder { |
| public CryptoAPIEncryptionInfoBuilder() { |
| } |
| |
| /** |
| * initialize the builder from a stream |
| */ |
| @Override |
| public void initialize(EncryptionInfo info, LittleEndianInput dis) |
| throws IOException { |
| /* int hSize = */ dis.readInt(); |
| CryptoAPIEncryptionHeader header = new CryptoAPIEncryptionHeader(dis); |
| info.setHeader(header); |
| info.setVerifier(new CryptoAPIEncryptionVerifier(dis, header)); |
| CryptoAPIDecryptor dec = new CryptoAPIDecryptor(); |
| dec.setEncryptionInfo(info); |
| info.setDecryptor(dec); |
| CryptoAPIEncryptor enc = new CryptoAPIEncryptor(); |
| enc.setEncryptionInfo(info); |
| info.setEncryptor(enc); |
| } |
| |
| /** |
| * initialize the builder from scratch |
| */ |
| @Override |
| public void initialize(EncryptionInfo info, |
| CipherAlgorithm cipherAlgorithm, HashAlgorithm hashAlgorithm, |
| int keyBits, int blockSize, ChainingMode chainingMode) { |
| if (cipherAlgorithm == null) { |
| cipherAlgorithm = CipherAlgorithm.rc4; |
| } |
| if (hashAlgorithm == null) { |
| hashAlgorithm = HashAlgorithm.sha1; |
| } |
| if (keyBits == -1) { |
| keyBits = 0x28; |
| } |
| assert(cipherAlgorithm == CipherAlgorithm.rc4 && hashAlgorithm == HashAlgorithm.sha1); |
| |
| info.setHeader(new CryptoAPIEncryptionHeader(cipherAlgorithm, hashAlgorithm, keyBits, blockSize, chainingMode)); |
| info.setVerifier(new CryptoAPIEncryptionVerifier(cipherAlgorithm, hashAlgorithm, keyBits, blockSize, chainingMode)); |
| CryptoAPIDecryptor dec = new CryptoAPIDecryptor(); |
| dec.setEncryptionInfo(info); |
| info.setDecryptor(dec); |
| CryptoAPIEncryptor enc = new CryptoAPIEncryptor(); |
| enc.setEncryptionInfo(info); |
| info.setEncryptor(enc); |
| } |
| } |