natural commented on a change in pull request #3594: NIFI-3833 Support for Encrypted Flow File Repositories URL: https://github.com/apache/nifi/pull/3594#discussion_r323575201
########## File path: nifi-commons/nifi-write-ahead-log/src/main/java/org/apache/nifi/wali/SimpleCipherInputStream.java ########## @@ -0,0 +1,104 @@ +/* + * 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.nifi.wali; + +import org.bouncycastle.crypto.io.CipherInputStream; +import org.bouncycastle.crypto.modes.AEADBlockCipher; + +import javax.crypto.SecretKey; +import java.io.IOException; +import java.io.InputStream; + +/** + * This class extends {@link CipherInputStream} with a static factory method for constructing + * an input stream with an AEAD block cipher. + */ +public class SimpleCipherInputStream extends CipherInputStream { + protected AEADBlockCipher cipher; + + /** + * Constructs an {@link InputStream} from an existing {@link InputStream} and block cipher. + * + * @param in input stream to wrap. + * @param cipher block cipher, initialized for decryption. + */ + public SimpleCipherInputStream(InputStream in, AEADBlockCipher cipher) { + super(in, cipher); + this.cipher = cipher; + } + + /** + * Static factory for wrapping an input stream with a block cipher. + * + * NB: this function eagerly reads the initial cipher values from the plain input stream before returning the cipher stream. + * + * @param in input stream to wrap. + * @param key cipher key. + * @return wrapped input stream. + * @throws IOException if the stream cannot be read eagerly, or if the cipher cannot be initialized. + */ + public static InputStream wrapWithKey(InputStream in, SecretKey key) throws IOException { + if (key == null) { + return in; + } + + if (in.markSupported()) { + in.mark(0); + } + + // Read the marker, the iv, and the aad in the same order as they're written in the SimpleCipherOutputStream: + try { + final int marker = in.read(); + if (marker != SimpleCipherUtil.MARKER_BYTE) { + if (in.markSupported()) { + in.reset(); + } + return in; + } + + byte[] iv = new byte[SimpleCipherUtil.IV_BYTE_LEN]; + int len = in.read(iv); + if (len != iv.length) { + throw new IOException("Could not read IV."); + } + + byte[] aad = new byte[SimpleCipherUtil.AAD_BYTE_LEN]; + len = in.read(aad); + if (len != aad.length) { + throw new IOException("Could not read AAD."); + } + + AEADBlockCipher cipher = SimpleCipherUtil.initCipher(key, false, iv, aad); + return new SimpleCipherInputStream(in, cipher); + + } catch (final IOException ignored) { + if (in.markSupported()) { + in.reset(); + } + return in; + } + } + + @Override + public void close() throws IOException { + try { Review comment: Ah, my bad for not using the specific exception. The base class implementation throws `InvalidCipherTextIOException`, so I've updated the code to catch that + rethrow the `IOException`. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services