[Cyberduck-trac] [Cyberduck] #10704: FTP Feature 'File transfer: use browser connection' does not work

[Cyberduck]

#10704: FTP Feature  'File transfer: use browser connection' does not work
-----------------------+-------------------
    Reporter:  zapta   |      Owner:
        Type:  defect  |     Status:  new
    Priority:  normal  |  Milestone:
   Component:  core    |    Version:  6.9.4
    Severity:  normal  |   Keywords:  ftp
Architecture:  Intel   |   Platform:
-----------------------+-------------------
 To reproduce:

 1. Using Cyberduck 6.9.4 on Mac OSX (I am using 10.14.4) define an FTP
 connection with this parameters https://i.imgur.com/ILpx6h0.png  (notice
 the 'Use browser connection' and 'PASV' settings)

 2. Setup a network sniffer to view the cyberduck traffic (I am using
 Wireshark)

 3. Establish the ftp connection and open a directory with a file.

 4. Initiate a Download operation and view the captured packets in the
 network sniffer.

 Expected:  Cyberduck use the existing FTP control connection to initiate a
 PASV file transfer (as it does when opening a sub directory in the FTP
 browser)

 Actual: Cyberduck tries to open a new command connection at the host FTP
 port (viewed as a SYNC packet).

 Impact: this prevents using Cyberduck with network appliances that are
 limited to a single FTP connection. FileZilla on the other hand works as
 expected with those appliances.

--
Ticket URL: <https://trac.cyberduck.io/ticket/10704>
Cyberduck <https://cyberduck.io>
Libre FTP, SFTP, WebDAV, S3 & OpenStack Swift browser for Mac and Windows