001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 * http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package org.apache.hadoop.hbase.io.crypto.aes;
019
020import java.io.InputStream;
021import java.security.InvalidAlgorithmParameterException;
022import java.security.InvalidKeyException;
023import java.security.Key;
024import javax.crypto.spec.IvParameterSpec;
025
026import org.apache.hadoop.hbase.io.crypto.Decryptor;
027import org.apache.yetus.audience.InterfaceAudience;
028import org.apache.yetus.audience.InterfaceStability;
029
030import org.apache.hbase.thirdparty.com.google.common.base.Preconditions;
031
032@InterfaceAudience.Private
033@InterfaceStability.Evolving
034public class AESDecryptor implements Decryptor {
035
036  private javax.crypto.Cipher cipher;
037  private Key key;
038  private byte[] iv;
039  private boolean initialized = false;
040
041  public AESDecryptor(javax.crypto.Cipher cipher) {
042    this.cipher = cipher;
043  }
044
045  javax.crypto.Cipher getCipher() {
046    return cipher;
047  }
048
049  @Override
050  public void setKey(Key key) {
051    Preconditions.checkNotNull(key, "Key cannot be null");
052    this.key = key;
053  }
054
055  @Override
056  public int getIvLength() {
057    return AES.IV_LENGTH;
058  }
059
060  @Override
061  public int getBlockSize() {
062    return AES.BLOCK_SIZE;
063  }
064
065  @Override
066  public void setIv(byte[] iv) {
067    Preconditions.checkNotNull(iv, "IV cannot be null");
068    Preconditions.checkArgument(iv.length == AES.IV_LENGTH, "Invalid IV length");
069    this.iv = iv;
070  }
071
072  @Override
073  public InputStream createDecryptionStream(InputStream in) {
074    if (!initialized) {
075      init();
076    }
077    return new javax.crypto.CipherInputStream(in, cipher);
078  }
079
080  @Override
081  public void reset() {
082    init();
083  }
084
085  protected void init() {
086    Preconditions.checkState(iv != null, "IV is null");
087    try {
088      cipher.init(javax.crypto.Cipher.DECRYPT_MODE, key, new IvParameterSpec(iv));
089    } catch (InvalidKeyException e) {
090      throw new RuntimeException(e);
091    } catch (InvalidAlgorithmParameterException e) {
092      throw new RuntimeException(e);
093    }
094    initialized = true;
095  }
096
097}