[NET-702] FTPSClient fails on listFiles()

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 3.7.2, 3.8.0
• Component/s: FTP
• Assignee: Unassigned
• Reporter: Frits Jalvingh
• Created: 06/Jul/21 18:29
• Updated: 26/Jul/21 12:43

Description

Calling ftpsclient.listFiles() fails in all ways.

See the program below.

Not having the "magic incantations" (execPROT("P")) makes it fail because it returns no files without ANY indication of error, even though the remote server answered with a "522 data connections must be encrypted" error. This is silent failure.

If you do add the execPROC call then listFiles fails with the following exception:

Exception in thread "main" javax.net.ssl.SSLProtocolException: Received close_notify during handshakeException in thread "main" javax.net.ssl.SSLProtocolException: Received close_notify during handshake at java.base/sun.security.ssl.Alert.createSSLException(Alert.java:129) at java.base/sun.security.ssl.Alert.createSSLException(Alert.java:117) at java.base/sun.security.ssl.TransportContext.fatal(TransportContext.java:308) at java.base/sun.security.ssl.TransportContext.fatal(TransportContext.java:264) at java.base/sun.security.ssl.TransportContext.fatal(TransportContext.java:255) at java.base/sun.security.ssl.Alert$AlertConsumer.consume(Alert.java:250) at java.base/sun.security.ssl.TransportContext.dispatch(TransportContext.java:181) at java.base/sun.security.ssl.SSLTransport.decode(SSLTransport.java:164) at java.base/sun.security.ssl.SSLSocketImpl.decode(SSLSocketImpl.java:1155) at java.base/sun.security.ssl.SSLSocketImpl.readApplicationRecord(SSLSocketImpl.java:1125) at java.base/sun.security.ssl.SSLSocketImpl$AppInputStream.read(SSLSocketImpl.java:823) at java.base/sun.nio.cs.StreamDecoder.readBytes(StreamDecoder.java:284) at java.base/sun.nio.cs.StreamDecoder.implRead(StreamDecoder.java:326) at java.base/sun.nio.cs.StreamDecoder.read(StreamDecoder.java:178) at java.base/java.io.InputStreamReader.read(InputStreamReader.java:185) at java.base/java.io.BufferedReader.fill(BufferedReader.java:161) at java.base/java.io.BufferedReader.readLine(BufferedReader.java:326) at java.base/java.io.BufferedReader.readLine(BufferedReader.java:392) at org.apache.commons.net.ftp.FTPFileEntryParserImpl.readNextEntry(FTPFileEntryParserImpl.java:53) at org.apache.commons.net.ftp.FTPListParseEngine.read(FTPListParseEngine.java:139) at org.apache.commons.net.ftp.FTPListParseEngine.readServerList(FTPListParseEngine.java:119) at org.apache.commons.net.ftp.FTPClient.initiateListParsing(FTPClient.java:2264) at org.apache.commons.net.ftp.FTPClient.initiateListParsing(FTPClient.java:2390) at org.apache.commons.net.ftp.FTPClient.listFiles(FTPClient.java:2651) at org.apache.commons.net.ftp.FTPClient.listFiles(FTPClient.java:2595) at nl.skarp.dataloader.datasources.TestFtps.main(TestFtps.java:40)

 

The program I used:

public class TestFtps {
   static public void main(String[] args) throws Exception {
      FTPSClient client = new FTPSClient();
      client.connect("localhost");

      int reply = client.getReplyCode();
      if(!FTPReply.isPositiveCompletion(reply)) {
         throw new DataAccessConfigException("ftp(s) server refused connection");
      }
      client.enterLocalPassiveMode();                   // For firewall usage

      System.out.println("ftp: login");
      if(!client.login("jal", "possward")) {
         throw new DataAccessConfigException("ftp(s) login failed");
      }

      client.setFileType(FTP.BINARY_FILE_TYPE);
      client.type(FTP.BINARY_FILE_TYPE);

      System.out.println("ftp: set passive mode");

      //client.enterLocalPassiveMode();                 // For firewall usage
      System.out.println("Fixing ftps listing");

      FTPSClient ftpsClient = (FTPSClient) client;
      ftpsClient.execPROT("P");
      ftpsClient.execPBSZ(0);

      FTPFile[] ftpFiles = client.listFiles();
      for(FTPFile ftpFile : ftpFiles) {
         System.out.println("Got file " + ftpFile.getName());
      }
   }
}