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.UnsupportedEncodingException; 026import java.net.Inet6Address; 027import java.net.Socket; 028import java.net.SocketException; 029import java.util.ArrayList; 030import java.util.List; 031 032import org.apache.commons.net.util.Base64; 033 034/** 035 * Experimental attempt at FTP client that tunnels over an HTTP proxy connection. 036 * 037 * @since 2.2 038 */ 039public class FTPHTTPClient extends FTPClient { 040 private final String proxyHost; 041 private final int proxyPort; 042 private final String proxyUsername; 043 private final String proxyPassword; 044 045 private static final byte[] CRLF={'\r', '\n'}; 046 private final Base64 base64 = new Base64(); 047 048 public FTPHTTPClient(String proxyHost, int proxyPort, String proxyUser, String proxyPass) { 049 this.proxyHost = proxyHost; 050 this.proxyPort = proxyPort; 051 this.proxyUsername = proxyUser; 052 this.proxyPassword = proxyPass; 053 } 054 055 public FTPHTTPClient(String proxyHost, int proxyPort) { 056 this(proxyHost, proxyPort, null, null); 057 } 058 059 060 /** 061 * {@inheritDoc} 062 * 063 * @throws IllegalStateException if connection mode is not passive 064 */ 065 // Kept to maintain binary compatibility 066 // Not strictly necessary, but Clirr complains even though there is a super-impl 067 @Override 068 protected Socket _openDataConnection_(int command, String arg) 069 throws IOException { 070 return super._openDataConnection_(command, arg); 071 } 072 073 /** 074 * {@inheritDoc} 075 * 076 * @throws IllegalStateException if connection mode is not passive 077 */ 078 @Override 079 protected Socket _openDataConnection_(String command, String arg) 080 throws IOException { 081 //Force local passive mode, active mode not supported by through proxy 082 if (getDataConnectionMode() != PASSIVE_LOCAL_DATA_CONNECTION_MODE) { 083 throw new IllegalStateException("Only passive connection mode supported"); 084 } 085 086 final boolean isInet6Address = getRemoteAddress() instanceof Inet6Address; 087 088 boolean attemptEPSV = isUseEPSVwithIPv4() || isInet6Address; 089 if (attemptEPSV && epsv() == FTPReply.ENTERING_EPSV_MODE) { 090 _parseExtendedPassiveModeReply(_replyLines.get(0)); 091 } else { 092 if (isInet6Address) { 093 return null; // Must use EPSV for IPV6 094 } 095 // If EPSV failed on IPV4, revert to PASV 096 if (pasv() != FTPReply.ENTERING_PASSIVE_MODE) { 097 return null; 098 } 099 _parsePassiveModeReply(_replyLines.get(0)); 100 } 101 102 Socket socket = new Socket(proxyHost, proxyPort); 103 InputStream is = socket.getInputStream(); 104 OutputStream os = socket.getOutputStream(); 105 tunnelHandshake(this.getPassiveHost(), this.getPassivePort(), is, os); 106 if ((getRestartOffset() > 0) && !restart(getRestartOffset())) { 107 socket.close(); 108 return null; 109 } 110 111 if (!FTPReply.isPositivePreliminary(sendCommand(command, arg))) { 112 socket.close(); 113 return null; 114 } 115 116 return socket; 117 } 118 119 @Override 120 public void connect(String host, int port) throws SocketException, IOException { 121 122 _socket_ = new Socket(proxyHost, proxyPort); 123 _input_ = _socket_.getInputStream(); 124 _output_ = _socket_.getOutputStream(); 125 try { 126 tunnelHandshake(host, port, _input_, _output_); 127 } 128 catch (Exception e) { 129 IOException ioe = new IOException("Could not connect to " + host+ " using port " + port); 130 ioe.initCause(e); 131 throw ioe; 132 } 133 super._connectAction_(); 134 } 135 136 private void tunnelHandshake(String host, int port, InputStream input, OutputStream output) throws IOException, 137 UnsupportedEncodingException { 138 final String connectString = "CONNECT " + host + ":" + port + " HTTP/1.1"; 139 final String hostString = "Host: " + host + ":" + port; 140 141 output.write(connectString.getBytes("UTF-8")); // TODO what is the correct encoding? 142 output.write(CRLF); 143 output.write(hostString.getBytes("UTF-8")); 144 output.write(CRLF); 145 146 if (proxyUsername != null && proxyPassword != null) { 147 final String auth = proxyUsername + ":" + proxyPassword; 148 final String header = "Proxy-Authorization: Basic " 149 + base64.encodeToString(auth.getBytes("UTF-8")); 150 output.write(header.getBytes("UTF-8")); 151 } 152 output.write(CRLF); 153 154 List<String> response = new ArrayList<String>(); 155 BufferedReader reader = new BufferedReader( 156 new InputStreamReader(input)); 157 158 for (String line = reader.readLine(); line != null 159 && line.length() > 0; line = reader.readLine()) { 160 response.add(line); 161 } 162 163 int size = response.size(); 164 if (size == 0) { 165 throw new IOException("No response from proxy"); 166 } 167 168 String code = null; 169 String resp = response.get(0); 170 if (resp.startsWith("HTTP/") && resp.length() >= 12) { 171 code = resp.substring(9, 12); 172 } else { 173 throw new IOException("Invalid response from proxy: " + resp); 174 } 175 176 if (!"200".equals(code)) { 177 StringBuilder msg = new StringBuilder(); 178 msg.append("HTTPTunnelConnector: connection failed\r\n"); 179 msg.append("Response received from the proxy:\r\n"); 180 for (String line : response) { 181 msg.append(line); 182 msg.append("\r\n"); 183 } 184 throw new IOException(msg.toString()); 185 } 186 } 187} 188 189