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.ftp; 019 020import java.io.BufferedReader; 021import java.io.IOException; 022import java.io.InputStream; 023import java.io.InputStreamReader; 024import java.io.OutputStream; 025import java.io.Reader; 026import java.io.UnsupportedEncodingException; 027import java.net.Inet6Address; 028import java.net.Socket; 029import java.net.SocketException; 030import java.nio.charset.Charset; 031import java.util.ArrayList; 032import java.util.List; 033 034import org.apache.commons.net.util.Base64; 035 036/** 037 * Experimental attempt at FTP client that tunnels over an HTTP proxy connection. 038 * 039 * @since 2.2 040 */ 041public class FTPHTTPClient extends FTPClient { 042 private final String proxyHost; 043 private final int proxyPort; 044 private final String proxyUsername; 045 private final String proxyPassword; 046 private final Charset charset; 047 048 private static final byte[] CRLF={'\r', '\n'}; 049 private final Base64 base64 = new Base64(); 050 051 private String tunnelHost; // Save the host when setting up a tunnel (needed for EPSV) 052 053 /** 054 * Create an instance with the specified encoding 055 * 056 * @param proxyHost the hostname to use 057 * @param proxyPort the port to use 058 * @param proxyUser the user name for the proxy 059 * @param proxyPass the password for the proxy 060 * @param encoding the encoding to use 061 */ 062 public FTPHTTPClient(final String proxyHost, final int proxyPort, final String proxyUser, final String proxyPass, 063 final Charset encoding) { 064 this.proxyHost = proxyHost; 065 this.proxyPort = proxyPort; 066 this.proxyUsername = proxyUser; 067 this.proxyPassword = proxyPass; 068 this.tunnelHost = null; 069 this.charset = encoding; 070 } 071 072 /** 073 * Create an instance using the UTF-8 encoding 074 * 075 * @param proxyHost the hostname to use 076 * @param proxyPort the port to use 077 * @param proxyUser the user name for the proxy 078 * @param proxyPass the password for the proxy 079 */ 080 public FTPHTTPClient(final String proxyHost, final int proxyPort, final String proxyUser, final String proxyPass) { 081 this(proxyHost, proxyPort, proxyUser, proxyPass, Charset.forName("UTF-8")); 082 } 083 084 /** 085 * Create an instance using the UTF-8 encoding, with no proxy credentials. 086 * 087 * @param proxyHost the hostname to use 088 * @param proxyPort the port to use 089 */ 090 public FTPHTTPClient(final String proxyHost, final int proxyPort) { 091 this(proxyHost, proxyPort, null, null); 092 } 093 094 095 /** 096 * Create an instance using the specified encoding, with no proxy credentials. 097 * 098 * @param proxyHost the hostname to use 099 * @param proxyPort the port to use 100 * @param encoding the encoding to use 101 */ 102 public FTPHTTPClient(final String proxyHost, final int proxyPort, final Charset encoding) { 103 this(proxyHost, proxyPort, null, null, encoding); 104 } 105 106 107 /** 108 * {@inheritDoc} 109 * 110 * @throws IllegalStateException if connection mode is not passive 111 * @deprecated (3.3) Use {@link FTPClient#_openDataConnection_(FTPCmd, String)} instead 112 */ 113 // Kept to maintain binary compatibility 114 // Not strictly necessary, but Clirr complains even though there is a super-impl 115 @Override 116 @Deprecated 117 protected Socket _openDataConnection_(final int command, final String arg) 118 throws IOException { 119 return super._openDataConnection_(command, arg); 120 } 121 122 /** 123 * {@inheritDoc} 124 * 125 * @throws IllegalStateException if connection mode is not passive 126 * @since 3.1 127 */ 128 @Override 129 protected Socket _openDataConnection_(final String command, final String arg) 130 throws IOException { 131 //Force local passive mode, active mode not supported by through proxy 132 if (getDataConnectionMode() != PASSIVE_LOCAL_DATA_CONNECTION_MODE) { 133 throw new IllegalStateException("Only passive connection mode supported"); 134 } 135 136 final boolean isInet6Address = getRemoteAddress() instanceof Inet6Address; 137 String passiveHost = null; 138 139 final boolean attemptEPSV = isUseEPSVwithIPv4() || isInet6Address; 140 if (attemptEPSV && epsv() == FTPReply.ENTERING_EPSV_MODE) { 141 _parseExtendedPassiveModeReply(_replyLines.get(0)); 142 passiveHost = this.tunnelHost; 143 } else { 144 if (isInet6Address) { 145 return null; // Must use EPSV for IPV6 146 } 147 // If EPSV failed on IPV4, revert to PASV 148 if (pasv() != FTPReply.ENTERING_PASSIVE_MODE) { 149 return null; 150 } 151 _parsePassiveModeReply(_replyLines.get(0)); 152 passiveHost = this.getPassiveHost(); 153 } 154 155 final Socket socket = _socketFactory_.createSocket(proxyHost, proxyPort); 156 final InputStream is = socket.getInputStream(); 157 final OutputStream os = socket.getOutputStream(); 158 tunnelHandshake(passiveHost, this.getPassivePort(), is, os); 159 if (getRestartOffset() > 0 && !restart(getRestartOffset())) { 160 socket.close(); 161 return null; 162 } 163 164 if (!FTPReply.isPositivePreliminary(sendCommand(command, arg))) { 165 socket.close(); 166 return null; 167 } 168 169 return socket; 170 } 171 172 @Override 173 public void connect(final String host, final int port) throws SocketException, IOException { 174 175 _socket_ = _socketFactory_.createSocket(proxyHost, proxyPort); 176 _input_ = _socket_.getInputStream(); 177 _output_ = _socket_.getOutputStream(); 178 Reader socketIsReader; 179 try { 180 socketIsReader = tunnelHandshake(host, port, _input_, _output_); 181 } 182 catch (final Exception e) { 183 final IOException ioe = new IOException("Could not connect to " + host+ " using port " + port); 184 ioe.initCause(e); 185 throw ioe; 186 } 187 super._connectAction_(socketIsReader); 188 } 189 190 private BufferedReader tunnelHandshake(final String host, final int port, final InputStream input, 191 final OutputStream output) throws IOException, UnsupportedEncodingException { 192 final String connectString = "CONNECT " + host + ":" + port + " HTTP/1.1"; 193 final String hostString = "Host: " + host + ":" + port; 194 195 this.tunnelHost = host; 196 output.write(connectString.getBytes(charset)); 197 output.write(CRLF); 198 output.write(hostString.getBytes(charset)); 199 output.write(CRLF); 200 201 if (proxyUsername != null && proxyPassword != null) { 202 final String auth = proxyUsername + ":" + proxyPassword; 203 final String header = "Proxy-Authorization: Basic " + base64.encodeToString(auth.getBytes(charset)); 204 output.write(header.getBytes(charset)); 205 } 206 output.write(CRLF); 207 208 final List<String> response = new ArrayList<>(); 209 final BufferedReader reader = new BufferedReader(new InputStreamReader(input, getCharset())); 210 211 for (String line = reader.readLine(); line != null && line.length() > 0; line = reader.readLine()) { 212 response.add(line); 213 } 214 215 final int size = response.size(); 216 if (size == 0) { 217 throw new IOException("No response from proxy"); 218 } 219 220 String code = null; 221 final String resp = response.get(0); 222 if (resp.startsWith("HTTP/") && resp.length() >= 12) { 223 code = resp.substring(9, 12); 224 } else { 225 throw new IOException("Invalid response from proxy: " + resp); 226 } 227 228 if (!"200".equals(code)) { 229 final StringBuilder msg = new StringBuilder(); 230 msg.append("HTTPTunnelConnector: connection failed\r\n"); 231 msg.append("Response received from the proxy:\r\n"); 232 for (final String line : response) { 233 msg.append(line); 234 msg.append("\r\n"); 235 } 236 throw new IOException(msg.toString()); 237 } 238 return reader; 239 } 240} 241 242