| /** |
| * 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.xml.security.encryption; |
| |
| import java.security.AccessController; |
| import java.security.PrivilegedAction; |
| import java.security.spec.AlgorithmParameterSpec; |
| |
| import javax.crypto.spec.IvParameterSpec; |
| |
| import org.apache.xml.security.utils.ClassLoaderUtils; |
| import org.apache.xml.security.utils.EncryptionConstants; |
| |
| public final class XMLCipherUtil { |
| |
| private static final org.slf4j.Logger LOG = |
| org.slf4j.LoggerFactory.getLogger(XMLCipherUtil.class); |
| |
| private static final boolean gcmUseIvParameterSpec = |
| AccessController.doPrivileged((PrivilegedAction<Boolean>) |
| () -> Boolean.getBoolean("org.apache.xml.security.cipher.gcm.useIvParameterSpec")); |
| |
| /** |
| * Build an <code>AlgorithmParameterSpec</code> instance used to initialize a <code>Cipher</code> instance |
| * for block cipher encryption and decryption. |
| * |
| * @param algorithm the XML encryption algorithm URI |
| * @param iv the initialization vector |
| * @return the newly constructed AlgorithmParameterSpec instance, appropriate for the |
| * specified algorithm |
| */ |
| public static AlgorithmParameterSpec constructBlockCipherParameters(String algorithm, byte[] iv, Class<?> callingClass) { |
| if (EncryptionConstants.ALGO_ID_BLOCKCIPHER_AES128_GCM.equals(algorithm) |
| || EncryptionConstants.ALGO_ID_BLOCKCIPHER_AES192_GCM.equals(algorithm) |
| || EncryptionConstants.ALGO_ID_BLOCKCIPHER_AES256_GCM.equals(algorithm)) { |
| return constructBlockCipherParametersForGCMAlgorithm(algorithm, iv, callingClass); |
| } else { |
| LOG.debug("Saw non-AES-GCM mode block cipher, returning IvParameterSpec: {}", algorithm); |
| return new IvParameterSpec(iv); |
| } |
| } |
| |
| public static AlgorithmParameterSpec constructBlockCipherParameters(boolean gcmAlgorithm, byte[] iv, Class<?> callingClass) { |
| if (gcmAlgorithm) { |
| return constructBlockCipherParametersForGCMAlgorithm("AES/GCM/NoPadding", iv, callingClass); |
| } else { |
| LOG.debug("Saw non-AES-GCM mode block cipher, returning IvParameterSpec"); |
| return new IvParameterSpec(iv); |
| } |
| } |
| |
| private static AlgorithmParameterSpec constructBlockCipherParametersForGCMAlgorithm(String algorithm, byte[] iv, Class<?> callingClass) { |
| if (gcmUseIvParameterSpec) { |
| // This override allows to support Java 1.7+ with (usually older versions of) third-party security |
| // providers which support or even require GCM via IvParameterSpec rather than GCMParameterSpec, |
| // e.g. BouncyCastle <= 1.49 (really <= 1.50 due to a semi-related bug). |
| LOG.debug("Saw AES-GCM block cipher, using IvParameterSpec due to system property override: {}", algorithm); |
| return new IvParameterSpec(iv); |
| } |
| |
| LOG.debug("Saw AES-GCM block cipher, attempting to create GCMParameterSpec: {}", algorithm); |
| |
| try { |
| // This class only added in Java 1.7. So load reflectively until Santuario starts targeting a minimum of Java 1.7. |
| Class<?> gcmSpecClass = ClassLoaderUtils.loadClass("javax.crypto.spec.GCMParameterSpec", callingClass); |
| |
| // XML Encryption 1.1 mandates a 128-bit Authentication Tag for AES GCM modes. |
| AlgorithmParameterSpec gcmSpec = (AlgorithmParameterSpec) gcmSpecClass.getConstructor(int.class, byte[].class) |
| .newInstance(128, iv); |
| LOG.debug("Successfully created GCMParameterSpec"); |
| return gcmSpec; |
| } catch (Exception e) { |
| // This handles the case of Java < 1.7 with a third-party security provider that |
| // supports GCM mode using only an IvParameterSpec, such as BouncyCastle. |
| LOG.debug("Failed to create GCMParameterSpec, falling back to returning IvParameterSpec", e); |
| return new IvParameterSpec(iv); |
| } |
| } |
| } |