Re: How to suppress ftp code '230 (username) logged on'

Oh, I agree it is weak as a kitten.

Rob Berendt
-- 
"They that can give up essential liberty to obtain a little temporary 
safety deserve neither liberty nor safety." 
Benjamin Franklin 




Scott Klement <klemscot@xxxxxxxxxxxx>
Sent by: midrange-l-bounces@xxxxxxxxxxxx
03/17/2003 03:01 PM
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        Subject:        Re: How to suppress ftp code '230 (username) 
logged on'



A better way to enforce a certain client is to use SSL and only allow
connections from clients bearing a certain certificate.

Your method would only keep out those that didn't understand what they
were doing.  An FTP hacker would have no problem circumventing it.


On Mon, 17 Mar 2003 rob@xxxxxxxxx wrote:

> Two points to this.  Read both.
>
> First,  I goofed.  Instead of changing message TCP11AF in message file
> QTCP/QTCPMSGF (and any other NLS libraries you may have loaded) from 
'230
> &1 logged on.' to '230 User logged on.', I accidentally dropped the 230
> part.  This locked all users out of ftp.  The 230 is required by the 
RFC's
> etc.
>
> Second point.  If you want to cause major grief for any client accessing
> ftp instead of one you created you can go ahead and make a change like 
the
> above.  Then in your custom written client you can violate this RFC and
> make this perfectly acceptable.  Maybe even change the 230 to a 530.
> Granted it is a little like 'security by obscurity'.  Personally, I 
think
> the exit points are a better way to handle security.  But enforcing your
> client may help in those cases in which you want to ensure a certain
> action is performed in a certain sequence.
>
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