Re: [rdesktop-devel] rdesktop: logon parameters and legal notice banner?

[<as...@ce...>]

On Wed, 20 Sep 2006, Paul Jansen wrote:

> Our servers all have legal banners that have to be
> acknowleged before you get to the actual login screen.
>  Searching through some of the 'devel' and 'users'
> archives doesn't seem to give any hints as to how to
> use the auto-logon parameters specififed on the
> command line to acknowledge the banner and continue to
> auto logon.  If this is supported and I'm just missing
> this somewhere can someone post some info on how to do
> this?

As far as I know, there's no support in the RDP protocol for doing 
something like this. After all, the idea is that the user should manually 
ack the legal banner. 

Without proper support, the solution will be a little bit "hackish". One 
could for example wait a few seconds and then send a simulated Enter 
press. This is not very reliable, though. Another option is to searching 
for a known bitmap pattern, but the bitmaps can change with different 
versions of Windows. 

The most promising solution, although still a little bit hackish, is to 
look for certain glyph sequences. If the legal caption is, say "Warning! 
Do not logon!", you'll know that glyph 7 and 21 will be same (the 
exclaimation mark). So, when you see a sequence that matches, you can send 
the Enter press. 


> After further reading I came across a posting that
> mentioned that 'tsgrinder' - a terminal services brute
> force password cracking tool - is able to work even
> when there is a banner before the login screen.
> The source for the tsgrinder tool is available:
> http://www.hammerofgod.com/download.htm

Probably, it's sending Enter after some time. 


> Can the facility to acknowledge a legal banner be
> added to rdesktop?  I'm sure the ability to remotely
> automate a file transfer purely over an RDP virtual
> channel would be useful for a lot of people.

Agree. If you are able to find a good solution, please let us know. 
 
Regards, 
-- 
Peter Åstrand		ThinLinc Chief Developer
Cendio AB		http://www.cendio.se
Teknikringen 3
583 30 Linköping	Phone: +46-13-21 46 00