Apache Log4j Core Implementation provides the functional components of the logging system. Users are free to create their own plugins and include them in the logging configuration. Apache Log4j Core is a required module to use Apache Log4j.

Bytecode (Java 8) for Apache Log4j Core Implementation is provided in a separate JAR file like log4j-core-2.14.1.jar.

Source Code files for Apache Log4j API are provided in both binary packge like apache-log4j-2.14.1-bin.zip and source package like apache-log4j-2.14.1-src.zip. You can download them at Apache Log4j Website.

You can also browse Source Code files for Apache Log4j Core Implementation 2.14.1 below.

⏎ org/apache/logging/log4j/core/net/ssl/SslConfiguration.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.logging.log4j.core.net.ssl;

import java.security.KeyManagementException;
import java.security.KeyStoreException;
import java.security.NoSuchAlgorithmException;
import java.security.UnrecoverableKeyException;
import java.util.Objects;

import javax.net.ssl.KeyManager;
import javax.net.ssl.KeyManagerFactory;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLServerSocketFactory;
import javax.net.ssl.SSLSocketFactory;
import javax.net.ssl.TrustManager;
import javax.net.ssl.TrustManagerFactory;

import org.apache.logging.log4j.core.Core;
import org.apache.logging.log4j.core.config.plugins.Plugin;
import org.apache.logging.log4j.core.config.plugins.PluginAttribute;
import org.apache.logging.log4j.core.config.plugins.PluginElement;
import org.apache.logging.log4j.core.config.plugins.PluginFactory;
import org.apache.logging.log4j.status.StatusLogger;

/**
 *  SSL Configuration
 */
@Plugin(name = "Ssl", category = Core.CATEGORY_NAME, printObject = true)
public class SslConfiguration {
    private static final StatusLogger LOGGER = StatusLogger.getLogger();
    private final KeyStoreConfiguration keyStoreConfig;
    private final TrustStoreConfiguration trustStoreConfig;
    private final SSLContext sslContext;
    private final String protocol;
    private final boolean verifyHostName;

    private SslConfiguration(final String protocol, final KeyStoreConfiguration keyStoreConfig,
            final TrustStoreConfiguration trustStoreConfig, boolean verifyHostName) {
        this.keyStoreConfig = keyStoreConfig;
        this.trustStoreConfig = trustStoreConfig;
        this.protocol = protocol == null ? SslConfigurationDefaults.PROTOCOL : protocol;
        this.sslContext = this.createSslContext();
        this.verifyHostName = verifyHostName;
    }

    /**
     * Clears the secret fields in this object but still allow it to operate normally.
     */
    public void clearSecrets() {
        if (this.keyStoreConfig != null) {
            this.keyStoreConfig.clearSecrets();
        }
        if (this.trustStoreConfig != null) {
            this.trustStoreConfig.clearSecrets();
        }
    }

    public SSLSocketFactory getSslSocketFactory() {
        return sslContext.getSocketFactory();
    }

    public SSLServerSocketFactory getSslServerSocketFactory() {
        return sslContext.getServerSocketFactory();
    }

    private SSLContext createSslContext() {
        SSLContext context = null;

        try {
            context = createSslContextBasedOnConfiguration();
            LOGGER.debug("Creating SSLContext with the given parameters");
        }
        catch (final TrustStoreConfigurationException e) {
            context = createSslContextWithTrustStoreFailure();
        }
        catch (final KeyStoreConfigurationException e) {
            context = createSslContextWithKeyStoreFailure();
        }
        return context;
    }

    private SSLContext createSslContextWithTrustStoreFailure() {
        SSLContext context;

        try {
            context = createSslContextWithDefaultTrustManagerFactory();
            LOGGER.debug("Creating SSLContext with default truststore");
        }
        catch (final KeyStoreConfigurationException e) {
            context = createDefaultSslContext();
            LOGGER.debug("Creating SSLContext with default configuration");
        }
        return context;
    }

    private SSLContext createSslContextWithKeyStoreFailure() {
        SSLContext context;

        try {
            context = createSslContextWithDefaultKeyManagerFactory();
            LOGGER.debug("Creating SSLContext with default keystore");
        }
        catch (final TrustStoreConfigurationException e) {
            context = createDefaultSslContext();
            LOGGER.debug("Creating SSLContext with default configuration");
        }
        return context;
    }

    private SSLContext createSslContextBasedOnConfiguration() throws KeyStoreConfigurationException, TrustStoreConfigurationException {
        return createSslContext(false, false);
    }

    private SSLContext createSslContextWithDefaultKeyManagerFactory() throws TrustStoreConfigurationException {
        try {
            return createSslContext(true, false);
        } catch (final KeyStoreConfigurationException dummy) {
             LOGGER.debug("Exception occurred while using default keystore. This should be a BUG");
             return null;
        }
    }

    private SSLContext createSslContextWithDefaultTrustManagerFactory() throws KeyStoreConfigurationException {
        try {
            return createSslContext(false, true);
        }
        catch (final TrustStoreConfigurationException dummy) {
            LOGGER.debug("Exception occurred while using default truststore. This should be a BUG");
            return null;
        }
    }

    private SSLContext createDefaultSslContext() {
        try {
            return SSLContext.getDefault();
        } catch (final NoSuchAlgorithmException e) {
            LOGGER.error("Failed to create an SSLContext with default configuration", e);
            return null;
        }
    }

    private SSLContext createSslContext(final boolean loadDefaultKeyManagerFactory, final boolean loadDefaultTrustManagerFactory)
            throws KeyStoreConfigurationException, TrustStoreConfigurationException {
        try {
            KeyManager[] kManagers = null;
            TrustManager[] tManagers = null;

            final SSLContext newSslContext = SSLContext.getInstance(this.protocol);
            if (!loadDefaultKeyManagerFactory) {
                final KeyManagerFactory kmFactory = loadKeyManagerFactory();
                kManagers = kmFactory.getKeyManagers();
            }
            if (!loadDefaultTrustManagerFactory) {
                final TrustManagerFactory tmFactory = loadTrustManagerFactory();
                tManagers = tmFactory.getTrustManagers();
            }

            newSslContext.init(kManagers, tManagers, null);
            return newSslContext;
        }
        catch (final NoSuchAlgorithmException e) {
            LOGGER.error("No Provider supports a TrustManagerFactorySpi implementation for the specified protocol", e);
            throw new TrustStoreConfigurationException(e);
        }
        catch (final KeyManagementException e) {
            LOGGER.error("Failed to initialize the SSLContext", e);
            throw new KeyStoreConfigurationException(e);
        }
    }

    private TrustManagerFactory loadTrustManagerFactory() throws TrustStoreConfigurationException {
        if (trustStoreConfig == null) {
            throw new TrustStoreConfigurationException(new Exception("The trustStoreConfiguration is null"));
        }

        try {
            return trustStoreConfig.initTrustManagerFactory();
        }
        catch (final NoSuchAlgorithmException e) {
            LOGGER.error("The specified algorithm is not available from the specified provider", e);
            throw new TrustStoreConfigurationException(e);
        } catch (final KeyStoreException e) {
            LOGGER.error("Failed to initialize the TrustManagerFactory", e);
            throw new TrustStoreConfigurationException(e);
        }
    }

    private KeyManagerFactory loadKeyManagerFactory() throws KeyStoreConfigurationException {
        if (keyStoreConfig == null) {
            throw new KeyStoreConfigurationException(new Exception("The keyStoreConfiguration is null"));
        }

        try {
            return keyStoreConfig.initKeyManagerFactory();
        }
        catch (final NoSuchAlgorithmException e) {
            LOGGER.error("The specified algorithm is not available from the specified provider", e);
            throw new KeyStoreConfigurationException(e);
        } catch (final KeyStoreException e) {
            LOGGER.error("Failed to initialize the TrustManagerFactory", e);
            throw new KeyStoreConfigurationException(e);
        } catch (final UnrecoverableKeyException e) {
            LOGGER.error("The key cannot be recovered (e.g. the given password is wrong)", e);
            throw new KeyStoreConfigurationException(e);
        }
    }

    /**
     * Creates an SslConfiguration from a KeyStoreConfiguration and a TrustStoreConfiguration.
     *
     * @param protocol The protocol, see http://docs.oracle.com/javase/7/docs/technotes/guides/security/StandardNames.html#SSLContext
     * @param keyStoreConfig The KeyStoreConfiguration.
     * @param trustStoreConfig The TrustStoreConfiguration.
     * @return a new SslConfiguration
     */
    @PluginFactory
    public static SslConfiguration createSSLConfiguration(
            // @formatter:off
            @PluginAttribute("protocol") final String protocol,
            @PluginElement("KeyStore") final KeyStoreConfiguration keyStoreConfig,
            @PluginElement("TrustStore") final TrustStoreConfiguration trustStoreConfig) {
            // @formatter:on
        return new SslConfiguration(protocol, keyStoreConfig, trustStoreConfig, false);
    }

    /**
     * Creates an SslConfiguration from a KeyStoreConfiguration and a TrustStoreConfiguration.
     *
     * @param protocol The protocol, see http://docs.oracle.com/javase/7/docs/technotes/guides/security/StandardNames.html#SSLContext
     * @param keyStoreConfig The KeyStoreConfiguration.
     * @param trustStoreConfig The TrustStoreConfiguration.
     * @param verifyHostName whether or not to perform host name verification
     * @return a new SslConfiguration
     * @since 2.12
     */
    public static SslConfiguration createSSLConfiguration(
        // @formatter:off
        @PluginAttribute("protocol") final String protocol,
        @PluginElement("KeyStore") final KeyStoreConfiguration keyStoreConfig,
        @PluginElement("TrustStore") final TrustStoreConfiguration trustStoreConfig,
        @PluginAttribute("verifyHostName") final boolean verifyHostName) {
        // @formatter:on
        return new SslConfiguration(protocol, keyStoreConfig, trustStoreConfig, verifyHostName);
    }

    @Override
    public int hashCode() {
        return Objects.hash(keyStoreConfig, protocol, sslContext, trustStoreConfig);
    }

    @Override
    public boolean equals(final Object obj) {
        if (this == obj) {
            return true;
        }
        if (obj == null) {
            return false;
        }
        if (getClass() != obj.getClass()) {
            return false;
        }
        final SslConfiguration other = (SslConfiguration) obj;
        if (!Objects.equals(keyStoreConfig, other.keyStoreConfig)) {
            return false;
        }
        if (!Objects.equals(protocol, other.protocol)) {
            return false;
        }
        if (!Objects.equals(sslContext, other.sslContext)) {
            return false;
        }
        if (!Objects.equals(trustStoreConfig, other.trustStoreConfig)) {
            return false;
        }
        return true;
    }

    public KeyStoreConfiguration getKeyStoreConfig() {
        return keyStoreConfig;
    }

    public TrustStoreConfiguration getTrustStoreConfig() {
        return trustStoreConfig;
    }

    public SSLContext getSslContext() {
        return sslContext;
    }

    public String getProtocol() {
        return protocol;
    }

    public boolean isVerifyHostName() {
        return verifyHostName;
    }
}

⏎ org/apache/logging/log4j/core/net/ssl/SslConfiguration.java

Or download all of them as a single archive file:

File name: log4j-core-2.14.1-sources.jar
File size: 1281358 bytes
Release date: 2021-03-06
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