Java tutorial
/**************************************************************** * Licensed to the AOS Community (AOS) under one or more * * contributor license agreements. See the NOTICE file * * distributed with this work for additional information * * regarding copyright ownership. The AOS 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 io.aos.crypto.spl09; import java.util.Arrays; import javax.crypto.KeyGenerator; import javax.crypto.SecretKey; import org.bouncycastle.cms.CMSEnvelopedData; import org.bouncycastle.cms.CMSEnvelopedDataGenerator; import org.bouncycastle.cms.CMSProcessable; import org.bouncycastle.cms.CMSProcessableByteArray; import org.bouncycastle.cms.KEKRecipientId; import org.bouncycastle.cms.RecipientId; import org.bouncycastle.cms.RecipientInformation; import org.bouncycastle.cms.RecipientInformationStore; /** * Demonstrate creation and processing a key-encrypted key enveloped-message. */ public class KEKEnvelopedDataExample { public static void main(String... args) throws Exception { KeyGenerator keyGen = KeyGenerator.getInstance("DESEDE", "BC"); SecretKey key = keyGen.generateKey(); // set up the generator CMSEnvelopedDataGenerator edGen = new CMSEnvelopedDataGenerator(); byte[] kekID = new byte[] { 1, 2, 3, 4, 5 }; edGen.addKEKRecipient(key, kekID); // create the enveloped-data object CMSProcessable data = new CMSProcessableByteArray("Hello World!".getBytes()); CMSEnvelopedData enveloped = edGen.generate(data, CMSEnvelopedDataGenerator.AES128_CBC, "BC"); // recreate enveloped = new CMSEnvelopedData(enveloped.getEncoded()); // look for our recipient RecipientId recId = new KEKRecipientId(kekID); RecipientInformationStore recipients = enveloped.getRecipientInfos(); RecipientInformation recipient = recipients.get(recId); if (recipient != null) { // decrypt the data byte[] recData = recipient.getContent(key, "BC"); // compare recovered data to the original data if (Arrays.equals((byte[]) data.getContent(), recData)) { System.out.println("data recovery succeeded"); } else { System.out.println("data recovery failed"); } } else { System.out.println("could not find a matching recipient"); } } }