commons-net.jar is the bytecode of Apache Commons Net library, which implements the client side of many basic Internet protocols.

Apache Commons Net Source Code files are provided in the binary packge (commons-net-3.8.0-bin.zip). You can download it at Apache Commons Net Website.

The source code of commons-net-3.8.0.jar is provided below:

⏎ org/apache/commons/net/util/TrustManagerUtils.java

/*
 * 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.commons.net.util;

import java.security.GeneralSecurityException;
import java.security.KeyStore;
import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;

import javax.net.ssl.TrustManagerFactory;
import javax.net.ssl.X509TrustManager;

/**
 * TrustManager utilities for generating TrustManagers.
 *
 * @since 3.0
 */
public final class TrustManagerUtils
{
    private static class TrustManager implements X509TrustManager {

        private final boolean checkServerValidity;

        TrustManager(final boolean checkServerValidity) {
            this.checkServerValidity = checkServerValidity;
        }

        /**
         * Never generates a CertificateException.
         */
        @Override
        public void checkClientTrusted(final X509Certificate[] certificates, final String authType)
        {
        }

        @Override
        public void checkServerTrusted(final X509Certificate[] certificates, final String authType)
            throws CertificateException
        {
            if (checkServerValidity) {
                for (final X509Certificate certificate : certificates)
                {
                    certificate.checkValidity();
                }
            }
        }

        /**
         * @return an empty array of certificates
         */
        @Override
        public X509Certificate[] getAcceptedIssuers()
        {
            return NetConstants.EMPTY_X509_CERTIFICATE_ARRAY;
        }
    }

    private static final X509TrustManager ACCEPT_ALL=new TrustManager(false);

    private static final X509TrustManager CHECK_SERVER_VALIDITY=new TrustManager(true);

    /**
     * Generate a TrustManager that performs no checks.
     *
     * @return the TrustManager
     */
    public static X509TrustManager getAcceptAllTrustManager(){
        return ACCEPT_ALL;
    }

    /**
     * Generate a TrustManager that checks server certificates for validity,
     * but otherwise performs no checks.
     *
     * @return the validating TrustManager
     */
    public static X509TrustManager getValidateServerCertificateTrustManager(){
        return CHECK_SERVER_VALIDITY;
    }

    /**
     * Return the default TrustManager provided by the JVM.
     * <p>
     * This should be the same as the default used by
     *  {@link javax.net.ssl.SSLContext#init(javax.net.ssl.KeyManager[], javax.net.ssl.TrustManager[], java.security.SecureRandom)
     * SSLContext#init(KeyManager[], TrustManager[], SecureRandom)}
     * when the TrustManager parameter is set to {@code null}
     * @param keyStore the KeyStore to use, may be {@code null}
     * @return the default TrustManager
     * @throws GeneralSecurityException if an error occurs
     */
    public static X509TrustManager getDefaultTrustManager(final KeyStore keyStore) throws GeneralSecurityException {
        final String defaultAlgorithm = TrustManagerFactory.getDefaultAlgorithm();
        final TrustManagerFactory instance = TrustManagerFactory.getInstance(defaultAlgorithm);
        instance.init(keyStore);
        return (X509TrustManager) instance.getTrustManagers()[0];
    }

}

⏎ org/apache/commons/net/util/TrustManagerUtils.java

Or download all of them as a single archive file:

File name: commons-net-3.8.0-sources.jar
File size: 437325 bytes
Release date: 2020-01-22
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