cowrie ssh service is blocked while trying to connect using ftpget.

[christianbeland]

Describe the bug
cowrie ssh service is blocked while trying to connect using ftpget.

To Reproduce
Steps to reproduce the behavior:

1. Run cowrie ssh service
2. Connect 2 terminals to cowrie ssh
3. In one terminal, type: ftpget -v -u anonymous -p anonymous -P 21 greektaverna.tk .sh .sh
4. See that the other terminal connected through ssh is blocked until the ftpget comamnd times out in the first terminal.
5. See that no new connection is accepted until the ftpget comamnd times out in the first terminal.
6. Once the ftpget command times out, see all other active connection timing out.

Expected behavior
Other connections not affected by the ftpget command in another cowrie ssh session.

Is there configuration settings to avoid this behaviour?

[micheloosterhof]

Yes, so this is a side effect of the ftpget command using ftplib and now Twisted asynchronous functionality to do networking. This means that while the ftpget is in progress, it will run in the only thread available and all other ones are not active. The solution would be to rewrite ftpget using Twisted.