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;
025import org.apache.hadoop.hbase.io.crypto.Decryptor;
026import org.apache.yetus.audience.InterfaceAudience;
027import org.apache.yetus.audience.InterfaceStability;
028
029import org.apache.hbase.thirdparty.com.google.common.base.Preconditions;
030
031@InterfaceAudience.Private
032@InterfaceStability.Evolving
033public class AESDecryptor implements Decryptor {
034
035  private javax.crypto.Cipher cipher;
036  private Key key;
037  private byte[] iv;
038  private boolean initialized = false;
039
040  public AESDecryptor(javax.crypto.Cipher cipher) {
041    this.cipher = cipher;
042  }
043
044  javax.crypto.Cipher getCipher() {
045    return cipher;
046  }
047
048  @Override
049  public void setKey(Key key) {
050    Preconditions.checkNotNull(key, "Key cannot be null");
051    this.key = key;
052  }
053
054  @Override
055  public int getIvLength() {
056    return AES.IV_LENGTH;
057  }
058
059  @Override
060  public int getBlockSize() {
061    return AES.BLOCK_SIZE;
062  }
063
064  @Override
065  public void setIv(byte[] iv) {
066    Preconditions.checkNotNull(iv, "IV cannot be null");
067    Preconditions.checkArgument(iv.length == AES.IV_LENGTH, "Invalid IV length");
068    this.iv = iv;
069  }
070
071  @Override
072  public InputStream createDecryptionStream(InputStream in) {
073    if (!initialized) {
074      init();
075    }
076    return new javax.crypto.CipherInputStream(in, cipher);
077  }
078
079  @Override
080  public void reset() {
081    init();
082  }
083
084  protected void init() {
085    Preconditions.checkState(iv != null, "IV is null");
086    try {
087      cipher.init(javax.crypto.Cipher.DECRYPT_MODE, key, new IvParameterSpec(iv));
088    } catch (InvalidKeyException e) {
089      throw new RuntimeException(e);
090    } catch (InvalidAlgorithmParameterException e) {
091      throw new RuntimeException(e);
092    }
093    initialized = true;
094  }
095
096}