    001/*
    002 * Licensed to the Apache Software Foundation (ASF) under one or more
    003 * contributor license agreements.  See the NOTICE file distributed with
    004 * this work for additional information regarding copyright ownership.
    005 * The ASF licenses this file to You under the Apache License, Version 2.0
    006 * (the "License"); you may not use this file except in compliance with
    007 * the License.  You may obtain a copy of the License at
    008 *
    009 *      http://www.apache.org/licenses/LICENSE-2.0
    010 *
    011 * Unless required by applicable law or agreed to in writing, software
    012 * distributed under the License is distributed on an "AS IS" BASIS,
    013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    014 * See the License for the specific language governing permissions and
    015 * limitations under the License.
    016 */
    017
    018package org.apache.commons.net.util;
    019
    020import java.security.GeneralSecurityException;
    021import java.security.KeyStore;
    022import java.security.cert.CertificateException;
    023import java.security.cert.X509Certificate;
    024
    025import javax.net.ssl.TrustManagerFactory;
    026import javax.net.ssl.X509TrustManager;
    027
    028/**
    029 * TrustManager utilities for generating TrustManagers.
    030 *
    031 * @since 3.0
    032 */
    033public final class TrustManagerUtils
    034{
    035    private static final X509Certificate[] EMPTY_X509CERTIFICATE_ARRAY = new X509Certificate[]{};
    036
    037    private static class TrustManager implements X509TrustManager {
    038
    039        private final boolean checkServerValidity;
    040
    041        TrustManager(final boolean checkServerValidity) {
    042            this.checkServerValidity = checkServerValidity;
    043        }
    044
    045        /**
    046         * Never generates a CertificateException.
    047         */
    048        @Override
    049        public void checkClientTrusted(final X509Certificate[] certificates, final String authType)
    050        {
    051            return;
    052        }
    053
    054        @Override
    055        public void checkServerTrusted(final X509Certificate[] certificates, final String authType)
    056            throws CertificateException
    057        {
    058            if (checkServerValidity) {
    059                for (final X509Certificate certificate : certificates)
    060                {
    061                    certificate.checkValidity();
    062                }
    063            }
    064        }
    065
    066        /**
    067         * @return an empty array of certificates
    068         */
    069        @Override
    070        public X509Certificate[] getAcceptedIssuers()
    071        {
    072            return EMPTY_X509CERTIFICATE_ARRAY;
    073        }
    074    }
    075
    076    private static final X509TrustManager ACCEPT_ALL=new TrustManager(false);
    077
    078    private static final X509TrustManager CHECK_SERVER_VALIDITY=new TrustManager(true);
    079
    080    /**
    081     * Generate a TrustManager that performs no checks.
    082     *
    083     * @return the TrustManager
    084     */
    085    public static X509TrustManager getAcceptAllTrustManager(){
    086        return ACCEPT_ALL;
    087    }
    088
    089    /**
    090     * Generate a TrustManager that checks server certificates for validity,
    091     * but otherwise performs no checks.
    092     *
    093     * @return the validating TrustManager
    094     */
    095    public static X509TrustManager getValidateServerCertificateTrustManager(){
    096        return CHECK_SERVER_VALIDITY;
    097    }
    098
    099    /**
    100     * Return the default TrustManager provided by the JVM.
    101     * <p>
    102     * This should be the same as the default used by
    103     *  {@link javax.net.ssl.SSLContext#init(javax.net.ssl.KeyManager[], javax.net.ssl.TrustManager[], java.security.SecureRandom)
    104     * SSLContext#init(KeyManager[], TrustManager[], SecureRandom)}
    105     * when the TrustManager parameter is set to {@code null}
    106     * @param keyStore the KeyStore to use, may be {@code null}
    107     * @return the default TrustManager
    108     * @throws GeneralSecurityException if an error occurs
    109     */
    110    public static X509TrustManager getDefaultTrustManager(final KeyStore keyStore) throws GeneralSecurityException {
    111        final String defaultAlgorithm = TrustManagerFactory.getDefaultAlgorithm();
    112        final TrustManagerFactory instance = TrustManagerFactory.getInstance(defaultAlgorithm);
    113        instance.init(keyStore);
    114        return (X509TrustManager) instance.getTrustManagers()[0];
    115    }
    116
    117}