我正在尝试使用基于apache example和FTPSClient class的Apache Commons Net库开发Java FTPS客户端。要运行de代码我正在使用Java 8，更新45。
当我调用方法“retrieveFile”时发生异常。我不确定，但我相信用于传输文件的连接不使用上面指定的HTTP代理。
使用FileZilla客户端，我可以使用相同的配置传输文件。
如何解决此问题？
我的代码：
// client with explicit security
FTPSClient ftps = new FTPSClient(false);
// HTTP proxy configuration
Proxy proxy = new Proxy(Type.HTTP, new InetSocketAddress("<REMOVED_FOR_SERCURITY>", <REMOVED_FOR_SERCURITY>));
ftps.setProxy(proxy);
// to show FTP commands in prompt
ftps.addProtocolCommandListener(new PrintCommandListener(new PrintWriter(System.out), true));
// disable remote host verification
ftps.setRemoteVerificationEnabled(false);
// trust in ALL
ftps.setTrustManager(TrustManagerUtils.getAcceptAllTrustManager());
// send keepAlive every 30 seconds
ftps.setControlKeepAliveTimeout(10l);
// data transfer timeout
ftps.setDataTimeout(30000);
// connect
ftps.connect("<REMOVED_FOR_SERCURITY>", <REMOVED_FOR_SERCURITY>);
ftps.login("<REMOVED_FOR_SERCURITY>", "<REMOVED_FOR_SERCURITY>");
// config
ftps.setCharset(Charset.forName("UTF-8"));
ftps.setBufferSize(0);
ftps.setFileType(FTP.BINARY_FILE_TYPE);
ftps.enterLocalPassiveMode();
ftps.execPROT("P");
// ... do some operations
ftps.retrieveFile("/dir1/dir2/fileX.zip", new ByteArrayOutputStream());
// close
ftps.logout();
ftps.disconnect();
输出：
220 (vsFTPd 2.2.2)
AUTH TLS
234 Proceed with negotiation.
USER *******
331 Please specify the password.
PASS *******
230 Login successful.
TYPE I
200 Switching to Binary mode.
PROT P
200 PROT now Private.
PASV
227 Entering Passive Mode (<REMOVED_FOR_SERCURITY>).
Exception in thread "main" java.net.ConnectException: Connection timed out: connect
at java.net.DualStackPlainSocketImpl.connect0(Native Method)
at java.net.DualStackPlainSocketImpl.socketConnect(DualStackPlainSocketImpl.java:79)
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:345)
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188)
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:172)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
at java.net.Socket.connect(Socket.java:589)
at sun.security.ssl.SSLSocketImpl.connect(SSLSocketImpl.java:656)
at org.apache.commons.net.ftp.FTPClient._openDataConnection_(FTPClient.java:894)
at org.apache.commons.net.ftp.FTPSClient._openDataConnection_(FTPSClient.java:600)
at org.apache.commons.net.ftp.FTPClient._retrieveFile(FTPClient.java:1854)
at org.apache.commons.net.ftp.FTPClient.retrieveFile(FTPClient.java:1845)
at br.com.bat.crm.test.util.FTPSClientTest.main(FTPSClientTest.java:57)
答案 0 :(得分：1)
我下载了commons-net 3.3的源代码，并通过HTTP代理客户端实现了我自己的FTPS。 它在调用方法keepAlive时遇到问题，正在给出异常＆＃34; java.net.SocketTimeoutException：read timed out＆＃34;。我不知道造成这个错误的原因。对我来说不是问题，因为我没有使用这个功能。
在类FTPClient中添加：
protected int getDataTimeout() {
return __dataTimeout;
}
在FTPSClient类中添加：
protected SSLContext getContext() {
return context;
}
创建了FTPSHTTPClient类：
package org.apache.commons.net.ftp;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.UnsupportedEncodingException;
import java.net.Inet6Address;
import java.net.InetSocketAddress;
import java.net.Socket;
import java.net.SocketException;
import java.util.ArrayList;
import java.util.List;
import javax.net.ssl.SSLSocket;
import org.apache.commons.net.util.Base64;
/**
* Experimental attempt at FTPS client that tunnels over an HTTP proxy connection.
*
* @author TECBMJNA
* @created 22/07/2015 09:29:45
*/
public class FTPSHTTPClient extends FTPSClient {
private final String proxyHost;
private final int proxyPort;
private final String proxyUsername;
private final String proxyPassword;
private String tunnelHost; // Save the host when setting up a tunnel (needed for EPSV)
private static final byte[] CRLF = { '\r', '\n' };
private final Base64 base64 = new Base64();
/**
* Constructor with proxy authentication
*
* @param proxyHost
* @param proxyPort
* @param proxyUser
* @param proxyPass
*
* @author TECBMJNA
* @created 22/07/2015 10:06:04
*/
public FTPSHTTPClient(String proxyHost, int proxyPort, String proxyUser, String proxyPass) {
super();
this.proxyHost = proxyHost;
this.proxyPort = proxyPort;
this.proxyUsername = proxyUser;
this.proxyPassword = proxyPass;
this.tunnelHost = null;
//TECBMJNA so funciona a partir do Java 8, pois Java 8 aceita proxy HTTP
//setProxy(new Proxy(Type.HTTP, new InetSocketAddress(proxyHost, proxyPort)));
}
/**
* Default constructor
*
* @param proxyHost
* @param proxyPort
*
* @author TECBMJNA
* @created 22/07/2015 10:06:14
*/
public FTPSHTTPClient(String proxyHost, int proxyPort) {
this(proxyHost, proxyPort, null, null);
}
/**
*
* @see org.apache.commons.net.ftp.FTPSClient#_openDataConnection_(java.lang.String, java.lang.String)
*/
@Override
protected Socket _openDataConnection_(String command, String arg) throws IOException {
//Force local passive mode, active mode not supported by through proxy
if (getDataConnectionMode() != PASSIVE_LOCAL_DATA_CONNECTION_MODE) {
throw new IllegalStateException("Only passive connection mode supported");
}
final boolean isInet6Address = getRemoteAddress() instanceof Inet6Address;
String passiveHost = null;
// Try EPSV command first on IPv6 - and IPv4 if enabled.
// When using IPv4 with NAT it has the advantage
// to work with more rare configurations.
// E.g. if FTP server has a static PASV address (external network)
// and the client is coming from another internal network.
// In that case the data connection after PASV command would fail,
// while EPSV would make the client succeed by taking just the port.
boolean attemptEPSV = isUseEPSVwithIPv4() || isInet6Address;
if (attemptEPSV && epsv() == FTPReply.ENTERING_EPSV_MODE) {
_parseExtendedPassiveModeReply(_replyLines.get(0));
passiveHost = this.tunnelHost;
} else {
if (isInet6Address) {
return null; // Must use EPSV for IPV6
}
// If EPSV failed on IPV4, revert to PASV
if (pasv() != FTPReply.ENTERING_PASSIVE_MODE) {
return null;
}
_parsePassiveModeReply(_replyLines.get(0));
passiveHost = this.getPassiveHost();
}
Socket proxySocket = new Socket();
if (getReceiveDataSocketBufferSize() > 0) {
proxySocket.setReceiveBufferSize(getReceiveDataSocketBufferSize());
}
if (getSendDataSocketBufferSize() > 0) {
proxySocket.setSendBufferSize(getSendDataSocketBufferSize());
}
if (getPassiveLocalIPAddress() != null) {
proxySocket.bind(new InetSocketAddress(getPassiveLocalIPAddress(), 0));
}
if (getDataTimeout() >= 0) {
proxySocket.setSoTimeout(getDataTimeout());
}
proxySocket.connect(new InetSocketAddress(proxyHost, proxyPort), getConnectTimeout());
tunnelHandshake(passiveHost, this.getPassivePort(), proxySocket.getInputStream(),
proxySocket.getOutputStream());
Socket socket = getContext().getSocketFactory().createSocket(proxySocket, passiveHost,
this.getPassivePort(), true);
if (getReceiveDataSocketBufferSize() > 0) {
socket.setReceiveBufferSize(getReceiveDataSocketBufferSize());
}
if (getSendDataSocketBufferSize() > 0) {
socket.setSendBufferSize(getSendDataSocketBufferSize());
}
if (getPassiveLocalIPAddress() != null) {
socket.bind(new InetSocketAddress(getPassiveLocalIPAddress(), 0));
}
if (getDataTimeout() >= 0) {
socket.setSoTimeout(getDataTimeout());
}
if ((getRestartOffset() > 0) && !restart(getRestartOffset())) {
proxySocket.close();
socket.close();
return null;
}
if (!FTPReply.isPositivePreliminary(sendCommand(command, arg))) {
proxySocket.close();
socket.close();
return null;
}
if (socket instanceof SSLSocket) {
SSLSocket sslSocket = (SSLSocket) socket;
sslSocket.setUseClientMode(getUseClientMode());
sslSocket.setEnableSessionCreation(getEnableSessionCreation());
// server mode
if (!getUseClientMode()) {
sslSocket.setNeedClientAuth(getNeedClientAuth());
sslSocket.setWantClientAuth(getWantClientAuth());
}
if (getEnabledCipherSuites() != null) {
sslSocket.setEnabledCipherSuites(getEnabledCipherSuites());
}
if (getEnabledProtocols() != null) {
sslSocket.setEnabledProtocols(getEnabledProtocols());
}
sslSocket.startHandshake();
}
return socket;
}
/**
*
* @see org.apache.commons.net.SocketClient#connect(java.lang.String, int)
*/
@Override
public void connect(String host, int port) throws SocketException, IOException {
_socket_ = new Socket(proxyHost, proxyPort);
_input_ = _socket_.getInputStream();
_output_ = _socket_.getOutputStream();
try {
tunnelHandshake(host, port, _input_, _output_);
} catch (Exception e) {
IOException ioe = new IOException("Could not connect to " + host + " using port " + port);
ioe.initCause(e);
throw ioe;
}
super._connectAction_();
}
/**
* Tunnels FTPS client connection over an HTTP proxy connection
*
* @param host
* @param port
* @param input
* @param output
* @throws IOException
* @throws UnsupportedEncodingException
*
* @author TECBMJNA
* @created 22/07/2015 09:32:23
*/
private void tunnelHandshake(String host, int port, InputStream input, OutputStream output) throws IOException,
UnsupportedEncodingException {
final String connectString = "CONNECT " + host + ":" + port + " HTTP/1.1";
final String hostString = "Host: " + host + ":" + port;
this.tunnelHost = host;
output.write(connectString.getBytes("UTF-8")); // TODO what is the correct encoding?
output.write(CRLF);
output.write(hostString.getBytes("UTF-8"));
output.write(CRLF);
if (proxyUsername != null && proxyPassword != null) {
final String auth = proxyUsername + ":" + proxyPassword;
final String header = "Proxy-Authorization: Basic " + base64.encodeToString(auth.getBytes("UTF-8"));
output.write(header.getBytes("UTF-8"));
}
output.write(CRLF);
output.flush();
List<String> response = new ArrayList<String>();
BufferedReader reader = new BufferedReader(new InputStreamReader(input, getCharsetName())); // Java 1.6 can use getCharset()
for (String line = reader.readLine(); line != null && line.length() > 0; line = reader.readLine()) {
response.add(line);
}
int size = response.size();
if (size == 0) {
throw new IOException("No response from proxy");
}
String code = null;
String resp = response.get(0);
if (resp.startsWith("HTTP/") && resp.length() >= 12) {
code = resp.substring(9, 12);
} else {
throw new IOException("Invalid response from proxy: " + resp);
}
if (!"200".equals(code)) {
StringBuilder msg = new StringBuilder();
msg.append("HTTPTunnelConnector: connection failed\r\n");
msg.append("Response received from the proxy:\r\n");
for (String line : response) {
msg.append(line);
msg.append("\r\n");
}
throw new IOException(msg.toString());
}
}
}
可以使用以下代码测试上述代码：
// client with explicit security, TLS protocol and tunneled over HTTP proxy
FTPSHTTPClient ftps = new FTPSHTTPClient(<REMOVED_FOR_SERCURITY>, <REMOVED_FOR_SERCURITY>);
// to show FTP commands in prompt
ftps.addProtocolCommandListener(new PrintCommandListener(new PrintWriter(System.out), true));
// disable remote host verification
ftps.setRemoteVerificationEnabled(false);
// trust in ALL
ftps.setTrustManager(TrustManagerUtils.getAcceptAllTrustManager());
// data transfer timeout
ftps.setDataTimeout(1800000); // 30
// keepAlive - DON'T USE, HAS A BUG WITH HTTP PROXY - java.net.SocketTimeoutException: Read timed out
//ftps.setControlKeepAliveTimeout(10l);
// connect
ftps.connect(<REMOVED_FOR_SERCURITY>, <REMOVED_FOR_SERCURITY>);
ftps.login(<REMOVED_FOR_SERCURITY>, <REMOVED_FOR_SERCURITY>);
// config
ftps.setCharset(Charset.forName("UTF-8"));
ftps.setBufferSize(0);
ftps.execPROT("P");
ftps.setFileType(FTP.BINARY_FILE_TYPE);
ftps.enterLocalPassiveMode();
// ... do some operations
ftps.changeWorkingDirectory(<REMOVED_FOR_SERCURITY>);
ftps.storeFile(<REMOVED_FOR_SERCURITY>, new FileInputStream(<REMOVED_FOR_SERCURITY>));
BufferedOutputStream outputStream = new BufferedOutputStream(new FileOutputStream(<REMOVED_FOR_SERCURITY>));
ftps.retrieveFile(<REMOVED_FOR_SERCURITY>, outputStream);
outputStream.close();
// close
ftps.logout();
ftps.disconnect();