FlashFXP won't connect with a proxy

Hi,

When I try to connect to a site with a proxy, I got this error:

[R] SOCKS Error: GSSAPI Authentication not supported
[R] Connection failed (Connection closed by client)

I tried with another FTP client and it works fine.

How can I fix it ?

I'm running FlashFXP 4.2.5 (build 1813) on Windows 8 x64 Pro.

Thanks

MxxCon asked me to update the ticket so I will do it...

THE BUG IS ALWAYS HERE!

Windows 8 x64 Pro
FlashFXP 4.3.0 build 1944

Log:
[R] Connecting to test via Proxy -> IP=xxx.xx.xx.xx PORT=xxxx
[R] SOCKS Error: GSSAPI Authentication not supported
[R] Connection failed

I just tested it with Windows 7 x64 Ultimate and I got the same issue!

For your info, I use mocks and proxy server. http://sourceforge.net/projects/mocks/

Anyone can reply this ticket to tell me it was considered ?

Thanks for your time!

I am quite confused by this error, it indicates that the proxy requires GSSAPI authentication but after reviewing the MOCKS source code I was unable to find any indication that it uses GSSAPI authentication.

In fact it would appear that MOCKS doesn't use any authentication at all.

I ran MOCKS on one of my test machines and was able to connect to it just fine with FlashFXP without any problems.

Did you make & compile MOCKS or did you run the pre-built binary? If you did perhaps something went wrong during the process?
Do you have MOCKS configured to connect to an upstream proxy?
Perhaps there is a problem with the MOCKS configuration?

Perhaps you might want to try another socks server such as
http://ss5.sourceforge.net/

Hi again,

I used mocks before with another FTP client and it worked fine.
I use these 2 configs to authenticate to my proxy:

UP_PROXY_USER = xxxxxx # These two can be missing if you
UP_PROXY_PASSWD = xxxxxxxx # are not required to authenticate

There is no ./configure and make in mocks...
I have to use this command to compile it. gcc -lnsl -o mocks child.c error.c misc.c socksd.c up_proxy.c

I dunno why it don't work...

Did you set the UP_PROXY_USER and UP_PROXY_PASSWD in your config file ?

I figured it out.

Remove the user and password set for the proxy server profile in FlashFXP and it will work just fine. with a user and password set it returns an error.

This is because MOCKS doesn't provide client authentication, it does however provide upstream authentication when chaining proxies via UP_PROXY_USER and UP_PROXY_PASSWD.

To complicate things it appears that the error reply sends the wrong error byte, it should return authentication failed with a value of #00, instead its returning #01 which indicates GSSAPI authentication required.

When a proxy user/password is set only the user/password authentication method is sent to the server, with no fall back methods the handshake fails.

We can remedy this and prevent over-complicating the issue by providing two methods to the socks server during the handshake (1. user/password) followed by (2. no authentication required). Had we done this we could of avoided the whole issue and the connection would of succeeded from the start without problems.

I will include this change in the next maintenance release, but in the meantime just remove the user/password from the socks profile.

If this socks proxy is accessible via the internet you'll want to make sure to configure the proper ALLOW/DENY IP rules to prevent just anyone from accessing it.