001/*
002 * Copyright 2023-2024 Ping Identity Corporation
003 * All Rights Reserved.
004 */
005/*
006 * Copyright 2023-2024 Ping Identity Corporation
007 *
008 * Licensed under the Apache License, Version 2.0 (the "License");
009 * you may not use this file except in compliance with the License.
010 * You may obtain a copy of the License at
011 *
012 *    http://www.apache.org/licenses/LICENSE-2.0
013 *
014 * Unless required by applicable law or agreed to in writing, software
015 * distributed under the License is distributed on an "AS IS" BASIS,
016 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
017 * See the License for the specific language governing permissions and
018 * limitations under the License.
019 */
020/*
021 * Copyright (C) 2023-2024 Ping Identity Corporation
022 *
023 * This program is free software; you can redistribute it and/or modify
024 * it under the terms of the GNU General Public License (GPLv2 only)
025 * or the terms of the GNU Lesser General Public License (LGPLv2.1 only)
026 * as published by the Free Software Foundation.
027 *
028 * This program is distributed in the hope that it will be useful,
029 * but WITHOUT ANY WARRANTY; without even the implied warranty of
030 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
031 * GNU General Public License for more details.
032 *
033 * You should have received a copy of the GNU General Public License
034 * along with this program; if not, see <http://www.gnu.org/licenses>.
035 */
036package com.unboundid.util;
037
038
039
040import java.net.InetSocketAddress;
041import java.net.Proxy;
042import javax.net.ssl.SSLSocketFactory;
043
044
045
046/**
047 * This class provides an implementation of a socket factory that can be used
048 * to forward traffic through a SOCKSv4 or SOCKSv5 proxy server.  Because of
049 * limitations in the Java support for SOCKS proxy servers, the following
050 * constraints will be imposed:
051 * <UL>
052 *   <LI>
053 *     Communication with the proxy server itself cannot be encrypted.  However,
054 *     it is possible to encrypt all communication through the proxy server to
055 *     the actual target server using TLS (by providing an
056 *     {@code SSLSocketFactory} instance when creating the
057 *     {@code SOCKSProxySocketFactory}), in which case the data will still be
058 *     protected from the client to that target server, and anyone observing the
059 *     communication between the client and the SOCKS proxy, or between the
060 *     SOCKS proxy and the target server, would not be able to decipher that
061 *     communication.
062 *   </LI>
063 *   <LI>
064 *     This implementation only provides direct support for proxy servers that
065 *     do not require authentication.  Although it may be possible to configure
066 *     authentication using Java system properties, this implementation does not
067 *     provide any direct support for authentication.
068 *   </LI>
069 * </UL>
070 * <BR><BR>
071 * <H2>Example</H2>
072 * The following example demonstrates the process for establishing an LDAPS
073 * connection through a SOCKS proxy server:
074 * <PRE>
075 *   final String socksProxyServerAddress = "socks-proxy.example.com";
076 *   final int socksProxyServerPort = 1080;
077 *   final int connectTimeoutMillis = 10_000;
078 *
079 *   final SSLUtil sslUtil =
080 *        new SSLUtil(new TrustStoreTrustManager("/path/to/trust/store"));
081 *   final SSLSocketFactory ldapsSocketFactory =
082 *        sslUtil.createSSLSocketFactory();
083 *
084 *   final SOCKSProxySocketFactory socksProxySocketFactory =
085 *        new SOCKSProxySocketFactory(socksProxyServerAddress,
086 *             socksProxyServerPort, connectTimeoutMillis,
087 *             ldapsSocketFactory);
088 *
089 *   final String ldapsServerAddress = "ds.example.com";
090 *   final int ldapsServerPort = 636;
091 *
092 *   try (LDAPConnection conn = new LDAPConnection(socksProxySocketFactory,
093 *        ldapsServerAddress, ldapsServerPort))
094 *   {
095 *     // Do something with the connection here.
096 *   }
097 * </PRE>
098 */
099@NotMutable()
100@ThreadSafety(level=ThreadSafetyLevel.COMPLETELY_THREADSAFE)
101public final class SOCKSProxySocketFactory
102       extends ProxySocketFactory
103{
104  /**
105   * Creates a new instance of this SOCKS socket factory with the provided
106   * settings.  The resulting socket factory will provide support for
107   * unencrypted LDAP communication.
108   *
109   * @param  socksProxyHost        The address of the SOCKS proxy server.  It
110   *                               must not be {@code null}.
111   * @param  socksProxyPort        The port on which the SOCKS proxy is
112   *                               listening for new connections.
113   * @param  connectTimeoutMillis  The maximum length of time in milliseconds to
114   *                               wait for a connection to be established.  A
115   *                               value that is less than or equal to zero
116   *                               indicates that no explicit timeout will be
117   *                               imposed.
118   */
119  public SOCKSProxySocketFactory(@NotNull final String socksProxyHost,
120                                 final int socksProxyPort,
121                                 final int connectTimeoutMillis)
122  {
123    this(socksProxyHost, socksProxyPort, connectTimeoutMillis, null);
124  }
125
126
127
128  /**
129   * Creates a new instance of this SOCKS socket factory with the provided
130   * settings.  The resulting socket factory may provide support for either
131   * unencrypted LDAP communication (if the provided {@code sslSocketFactory}
132   * value is {@code null}) or encrypted LDAPS communication (if the provided
133   * {@code sslSocketFactory} value is non-{@code null}).
134   *
135   * @param  socksProxyHost        The address of the SOCKS proxy server.  It
136   *                               must not be {@code null}.
137   * @param  socksProxyPort        The port on which the SOCKS proxy is
138   *                               listening for new connections.
139   * @param  connectTimeoutMillis  The maximum length of time in milliseconds to
140   *                               wait for a connection to be established.  A
141   *                               value that is less than or equal to zero
142   *                               indicates that no explicit timeout will be
143   *                               imposed.
144   * @param  sslSocketFactory      An SSL socket factory that should be used if
145   *                               communication with the target LDAP server
146   *                               should be encrypted with TLS.  It must be
147   *                               {@code null} if communication should not be
148   *                               encrypted, and it must not be {@code null} if
149   *                               communication should be encrypted with TLS.
150   */
151  public SOCKSProxySocketFactory(@NotNull final String socksProxyHost,
152              final int socksProxyPort,
153              final int connectTimeoutMillis,
154              @Nullable final SSLSocketFactory sslSocketFactory)
155  {
156    super(new Proxy(Proxy.Type.SOCKS,
157                    new InetSocketAddress(socksProxyHost, socksProxyPort)),
158         connectTimeoutMillis, sslSocketFactory);
159  }
160}