[NET-610] FTPClient.mlistFile incorrectly handles MLST reply

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 3.5
• Fix Version/s: 3.6
• Component/s: FTP
• Labels: easyfix patch

Environment

using some FTP-server incorrectly releasing RFC 3659. For example xlight ftp server (https://www.xlightftpd.com/)

• Flags: Patch, Important
• Assignee: Unassigned
• Reporter: Sergey Yanzin
• Created: 06/Feb/17 10:50
• Updated: 14/Feb/17 22:22
• Resolved: 07/Feb/17 15:40

Description

By RFC 3659 server must start fact with space character. But some inaccurate realisations reply without starting space.
But org.apache.commons.net.ftp.FTPClient.mlistFile() skips leading character even it is not a space:
public FTPFile mlistFile(String pathname) throws IOException
{
boolean success = FTPReply.isPositiveCompletion(sendCommand(FTPCmd.MLST, pathname));
if (success)

{ String entry = getReplyStrings()[1].substring(1); // skip leading space for parser return MLSxEntryParser.parseEntry(entry); }

else

{ return null; }
}


I think it is wrong. The method should throw exception, if first character is not a space. Or does not remove starting char (and should be some option responsible for that behaviour) if it is not a space.

my workaround in overriden method:
public FTPFile mlistFile(String pathname) throws IOException {
final boolean success = FTPReply.isPositiveCompletion(sendCommand(FTPCmd.MLST, pathname));
if (success) { final String reply = getReplyStrings()[1]; final String entry = reply.charAt(0) == ' ' ? reply.substring(1) : reply; return MLSxEntryParser.parseEntry(entry); } else { return null; }

}