| /* |
| * 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. |
| */ |
| |
| /* $Id$ */ |
| |
| package org.apache.fop.pdf; |
| |
| import java.lang.reflect.InvocationTargetException; |
| import java.lang.reflect.Method; |
| import java.security.Provider; |
| import java.security.Security; |
| |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.logging.LogFactory; |
| |
| /** |
| * This class acts as a factory for PDF encryption support. It enables the |
| * feature to be optional to FOP depending on the availability of JCE. |
| */ |
| public class PDFEncryptionManager { |
| |
| /** logging instance */ |
| protected static Log log = LogFactory.getLog(PDFEncryptionManager.class); |
| |
| /** |
| * Indicates whether JCE is available. |
| * @return boolean true if JCE is present |
| */ |
| public static boolean isJCEAvailable() { |
| try { |
| /*Class clazz =*/ Class.forName("javax.crypto.Cipher"); |
| return true; |
| } catch (ClassNotFoundException e) { |
| return false; |
| } |
| } |
| |
| /** |
| * Checks whether the necessary algorithms are available. |
| * @return boolean True if all necessary algorithms are present |
| */ |
| public static boolean checkAvailableAlgorithms() { |
| if (!isJCEAvailable()) { |
| return false; |
| } else { |
| Provider[] providers; |
| providers = Security.getProviders("Cipher.RC4"); |
| if (providers == null) { |
| log.warn("Cipher provider for RC4 not available."); |
| return false; |
| } |
| providers = Security.getProviders("MessageDigest.MD5"); |
| if (providers == null) { |
| log.warn("MessageDigest provider for MD5 not available."); |
| return false; |
| } |
| return true; |
| } |
| } |
| |
| |
| /** |
| * Sets up PDF encryption if PDF encryption is requested by registering |
| * a <code>PDFEncryptionParams</code> object with the user agent and if |
| * the necessary cryptographic support is available. |
| * @param params the PDF encryption params or null to disable encryption |
| * @param pdf the PDF document to setup encryption for |
| */ |
| public static void setupPDFEncryption(PDFEncryptionParams params, |
| PDFDocument pdf) { |
| if (pdf == null) { |
| throw new NullPointerException("PDF document must not be null"); |
| } |
| if (params != null) { |
| if (!checkAvailableAlgorithms()) { |
| if (isJCEAvailable()) { |
| log.warn("PDF encryption has been requested, JCE is " |
| + "available but there's no " |
| + "JCE provider available that provides the " |
| + "necessary algorithms. The PDF won't be " |
| + "encrypted."); |
| } else { |
| log.warn("PDF encryption has been requested but JCE is " |
| + "unavailable! The PDF won't be encrypted."); |
| } |
| } |
| pdf.setEncryption(params); |
| } |
| } |
| |
| /** |
| * Creates a new PDFEncryption instance if PDF encryption is available. |
| * @param objnum PDF object number |
| * @param params PDF encryption parameters |
| * @return PDFEncryption the newly created instance, null if PDF encryption |
| * is unavailable. |
| */ |
| public static PDFEncryption newInstance(int objnum, PDFEncryptionParams params) { |
| try { |
| Class clazz = Class.forName("org.apache.fop.pdf.PDFEncryptionJCE"); |
| Method makeMethod = clazz.getMethod("make", |
| new Class[] {int.class, PDFEncryptionParams.class}); |
| Object obj = makeMethod.invoke(null, |
| new Object[] {new Integer(objnum), params}); |
| return (PDFEncryption)obj; |
| } catch (ClassNotFoundException e) { |
| if (checkAvailableAlgorithms()) { |
| log.warn("JCE and algorithms available, but the " |
| + "implementation class unavailable. Please do a full " |
| + "rebuild."); |
| } |
| return null; |
| } catch (NoSuchMethodException e) { |
| log.error(e); |
| return null; |
| } catch (IllegalAccessException e) { |
| log.error(e); |
| return null; |
| } catch (InvocationTargetException e) { |
| log.error(e); |
| return null; |
| } |
| } |
| |
| } |