First of all, I should say I'm implementing partial features of protocols
which are practically useful and necessary at the time.
In message <_A4380@delegate-en.ML_> on 02/27/09(09:59:51)
you Jacob Lundberg <email@example.com> wrote:
|On Thu, 2009-02-26 at 14:40 +0900, Yutaka Sato wrote:
|> The problem is in the implicit-negotiation of SSL usage in FTPS of which
|> specification is not well specified. In your case, DeleGate is waiting
|> SSL negotiation from the client on the data-connection but lftp does not
|> do SSL (at least by default) for a FTPS server.
|Aha! Thank you for the information. I read some of RFC 2228 and I see
|the problem is that lftp never issues a PROT command (most likely
|because delegate does not list PROT in its supported commands when in
|ftps mode). So, I have delegate configured to require an encrypted data
|channel and lftp assumes it is PROT level C. I suppose this means my
|use of delegate is actually wrong according to the RFC. The RFC expects
As long as I know, FTPS using port #990 applies SSL without any
negotiation and nothing to do with RFC2228.
And what I can't understand is why you still try to use FTPS with a
client as lftp which does not need it, supporting the negotiation by
RFC2228 over the standard FTP port #21. It might be that you are
making a configuration which is commonly applicable to other
implementations of clients and servers, but I'm not sure...
|I did notice one problem. If delegate is configured to require
|encryption on the data channel, it will still accept "PROT C" from the
|client. So the client says "PROT C" and delegate says "200" but then
|the client will hang when it tries to download the file. I think the
|RFC is clear delegate should reject the PROT with "534" (protection
Yes it should be, but I did not think it so necessary, at least when I
implemented it, to disable SSL while negotiating about SSL.
Nowadays the usage of SSL for FTP becomes more usual and it might be
9 9 Yutaka Sato <firstname.lastname@example.org> http://delegate.org/y.sato/
( ~ ) National Institute of Advanced Industrial Science and Technology
_< >_ 1-1-4 Umezono, Tsukuba, Ibaraki, 305-8568 Japan
Do the more with the less -- B. Fuller