Support other FTPS PROT command options

[kevanb]

Per RFC-2228 supports four arguments to PROT:

C - Clear -neither integrity nor privacy
S - Safe - integrity without privacy
E - Confidential - privacy without integrity
P - Private - integrity and privacy

As of release 2.2.8c of FileZilla, if you specify a
remote site as server type "FTP over TLS (explicit
encryption)" (or "over SSL") the client sends "PROT P",
specifying to encrypt both control and data
connections. There should be an option in the client
to choose the level of protection you desire. Some FTP
servers (such as WS_FTP Server) now support allowing a
clear command channel after authentication for
compatibility with FTP application gateways/proxies
found in firewalls and NAT devices.

[Alexander Schuch]

Taken from closed duplicate #2387:

"It would be great to choose between 'PROT P' and 'PROT
C' in default settings and for each site in the
manager."

[Albert]

Patch for svn revision 5003. Adds support for PROT C command.

[Albert]

Hi,

I've added support for PROT C/P command option. By default, filezilla works as always, using PROT P. If you want to use PROT C, put something like that on your sitemanager.xml

<FileZilla3>

<Servers>

<Server>

[...]
<ProtLevel>C</ProtLevel>
[...]

[Tim Kosse]

I wonder, why not simply use plaintext FTP?

[Albert]

​Here you may find some reasons.

[Tim Kosse]

Please test it with queued files following a restart of FileZilla, it's not being saved there.

[Tim Kosse]

PROT C support won't be implemented as it is vulnerable to data connection stealing attacks.