View Javadoc

1   //
2   //  ========================================================================
3   //  Copyright (c) 1995-2016 Mort Bay Consulting Pty. Ltd.
4   //  ------------------------------------------------------------------------
5   //  All rights reserved. This program and the accompanying materials
6   //  are made available under the terms of the Eclipse Public License v1.0
7   //  and Apache License v2.0 which accompanies this distribution.
8   //
9   //      The Eclipse Public License is available at
10  //      http://www.eclipse.org/legal/epl-v10.html
11  //
12  //      The Apache License v2.0 is available at
13  //      http://www.opensource.org/licenses/apache2.0.php
14  //
15  //  You may elect to redistribute this code under either of these licenses.
16  //  ========================================================================
17  //
18  
19  package org.eclipse.jetty.client;
20  
21  import java.io.IOException;
22  import java.nio.ByteBuffer;
23  import java.nio.charset.StandardCharsets;
24  import java.util.Map;
25  import java.util.concurrent.Executor;
26  import java.util.regex.Matcher;
27  import java.util.regex.Pattern;
28  
29  import org.eclipse.jetty.client.api.Connection;
30  import org.eclipse.jetty.http.HttpScheme;
31  import org.eclipse.jetty.io.AbstractConnection;
32  import org.eclipse.jetty.io.ClientConnectionFactory;
33  import org.eclipse.jetty.io.EndPoint;
34  import org.eclipse.jetty.io.ssl.SslClientConnectionFactory;
35  import org.eclipse.jetty.util.BufferUtil;
36  import org.eclipse.jetty.util.Callback;
37  import org.eclipse.jetty.util.Promise;
38  import org.eclipse.jetty.util.log.Log;
39  import org.eclipse.jetty.util.log.Logger;
40  
41  public class Socks4Proxy extends ProxyConfiguration.Proxy
42  {
43      public Socks4Proxy(String host, int port)
44      {
45          this(new Origin.Address(host, port), false);
46      }
47  
48      public Socks4Proxy(Origin.Address address, boolean secure)
49      {
50          super(address, secure);
51      }
52  
53      @Override
54      public ClientConnectionFactory newClientConnectionFactory(ClientConnectionFactory connectionFactory)
55      {
56          return new Socks4ProxyClientConnectionFactory(connectionFactory);
57      }
58  
59      public static class Socks4ProxyClientConnectionFactory implements ClientConnectionFactory
60      {
61          private final ClientConnectionFactory connectionFactory;
62  
63          public Socks4ProxyClientConnectionFactory(ClientConnectionFactory connectionFactory)
64          {
65              this.connectionFactory = connectionFactory;
66          }
67  
68          @Override
69          public org.eclipse.jetty.io.Connection newConnection(EndPoint endPoint, Map<String, Object> context) throws IOException
70          {
71              HttpDestination destination = (HttpDestination)context.get(HttpClientTransport.HTTP_DESTINATION_CONTEXT_KEY);
72              Executor executor = destination.getHttpClient().getExecutor();
73              Socks4ProxyConnection connection = new Socks4ProxyConnection(endPoint, executor, connectionFactory, context);
74              return customize(connection, context);
75          }
76      }
77  
78      private static class Socks4ProxyConnection extends AbstractConnection implements Callback
79      {
80          private static final Pattern IPv4_PATTERN = Pattern.compile("(\\d{1,3})\\.(\\d{1,3})\\.(\\d{1,3})\\.(\\d{1,3})");
81          private static final Logger LOG = Log.getLogger(Socks4ProxyConnection.class);
82  
83          private final Socks4Parser parser = new Socks4Parser();
84          private final ClientConnectionFactory connectionFactory;
85          private final Map<String, Object> context;
86  
87          public Socks4ProxyConnection(EndPoint endPoint, Executor executor, ClientConnectionFactory connectionFactory, Map<String, Object> context)
88          {
89              super(endPoint, executor);
90              this.connectionFactory = connectionFactory;
91              this.context = context;
92          }
93  
94          @Override
95          public void onOpen()
96          {
97              super.onOpen();
98              writeSocks4Connect();
99          }
100 
101         /**
102          * Writes the SOCKS "connect" bytes, differentiating between SOCKS 4 and 4A;
103          * the former sends an IPv4 address, the latter the full domain name.
104          */
105         private void writeSocks4Connect()
106         {
107             HttpDestination destination = (HttpDestination)context.get(HttpClientTransport.HTTP_DESTINATION_CONTEXT_KEY);
108             String host = destination.getHost();
109             short port = (short)destination.getPort();
110             Matcher matcher = IPv4_PATTERN.matcher(host);
111             if (matcher.matches())
112             {
113                 // SOCKS 4
114                 ByteBuffer buffer = ByteBuffer.allocate(9);
115                 buffer.put((byte)4).put((byte)1).putShort(port);
116                 for (int i = 1; i <= 4; ++i)
117                     buffer.put((byte)Integer.parseInt(matcher.group(i)));
118                 buffer.put((byte)0);
119                 buffer.flip();
120                 getEndPoint().write(this, buffer);
121             }
122             else
123             {
124                 // SOCKS 4A
125                 byte[] hostBytes = host.getBytes(StandardCharsets.UTF_8);
126                 ByteBuffer buffer = ByteBuffer.allocate(9 + hostBytes.length + 1);
127                 buffer.put((byte)4).put((byte)1).putShort(port);
128                 buffer.put((byte)0).put((byte)0).put((byte)0).put((byte)1).put((byte)0);
129                 buffer.put(hostBytes).put((byte)0);
130                 buffer.flip();
131                 getEndPoint().write(this, buffer);
132             }
133         }
134 
135         @Override
136         public void succeeded()
137         {
138             if (LOG.isDebugEnabled())
139                 LOG.debug("Written SOCKS4 connect request");
140             fillInterested();
141         }
142 
143         @Override
144         public void failed(Throwable x)
145         {
146             close();
147             @SuppressWarnings("unchecked")
148             Promise<Connection> promise = (Promise<Connection>)context.get(HttpClientTransport.HTTP_CONNECTION_PROMISE_CONTEXT_KEY);
149             promise.failed(x);
150         }
151 
152         @Override
153         public void onFillable()
154         {
155             try
156             {
157                 while (true)
158                 {
159                     // Avoid to read too much from the socket: ask
160                     // the parser how much left there is to read.
161                     ByteBuffer buffer = BufferUtil.allocate(parser.expected());
162                     int filled = getEndPoint().fill(buffer);
163                     if (LOG.isDebugEnabled())
164                         LOG.debug("Read SOCKS4 connect response, {} bytes", filled);
165 
166                     if (filled < 0)
167                         throw new IOException("SOCKS4 tunnel failed, connection closed");
168 
169                     if (filled == 0)
170                     {
171                         fillInterested();
172                         return;
173                     }
174 
175                     if (parser.parse(buffer))
176                         return;
177                 }
178             }
179             catch (Throwable x)
180             {
181                 failed(x);
182             }
183         }
184 
185         private void onSocks4Response(int responseCode) throws IOException
186         {
187             if (responseCode == 0x5A)
188                 tunnel();
189             else
190                 throw new IOException("SOCKS4 tunnel failed with code " + responseCode);
191         }
192 
193         private void tunnel()
194         {
195             try
196             {
197                 HttpDestination destination = (HttpDestination)context.get(HttpClientTransport.HTTP_DESTINATION_CONTEXT_KEY);
198                 HttpClient client = destination.getHttpClient();
199                 ClientConnectionFactory connectionFactory = this.connectionFactory;
200                 if (HttpScheme.HTTPS.is(destination.getScheme()))
201                     connectionFactory = new SslClientConnectionFactory(client.getSslContextFactory(), client.getByteBufferPool(), client.getExecutor(), connectionFactory);
202                 org.eclipse.jetty.io.Connection newConnection = connectionFactory.newConnection(getEndPoint(), context);
203                 getEndPoint().upgrade(newConnection);
204                 if (LOG.isDebugEnabled())
205                     LOG.debug("SOCKS4 tunnel established: {} over {}", this, newConnection);
206             }
207             catch (Throwable x)
208             {
209                 failed(x);
210             }
211         }
212 
213         private class Socks4Parser
214         {
215             private static final int EXPECTED_LENGTH = 8;
216             private int cursor;
217             private int response;
218 
219             private boolean parse(ByteBuffer buffer) throws IOException
220             {
221                 while (buffer.hasRemaining())
222                 {
223                     byte current = buffer.get();
224                     if (cursor == 1)
225                         response = current & 0xFF;
226                     ++cursor;
227                     if (cursor == EXPECTED_LENGTH)
228                     {
229                         onSocks4Response(response);
230                         return true;
231                     }
232                 }
233                 return false;
234             }
235 
236             private int expected()
237             {
238                 return EXPECTED_LENGTH - cursor;
239             }
240         }
241     }
242 }