Re: TCP Wrappers

[Prentis Brooks <prentis at aol dot net>]

Ok, I was basing my response on the info I got from Charles, where he
pointed out that libwrap declares certain ints as extern, leaving tcpd
and ssh to define them.   I am not familiar with DLL's so I am going
solely by what he says, which I expect is accurate considering the work
he has already done.  According to his email, these externally defined
ints work fine when linked statically, but not in a DLL.  He suggested
that I go through and change the libwrap library to define these
variable and export them to the applications.  Once that is done, I have
to go through the applications and stop them from declaring these
variables themselves (this is the part where I do a lot of reading).  

Regarding changes to ssh, that is based on the assumption that ssh, like
tcpd, declares these ints itself and would need similiar edits to work
with the DLL.  Regarding the inetd, I was actually talking about making
the edits to tcpd and using inetd to test the functionality, since that
is the only other place I have used tcpwrap other than in SSH.

Does that clarify or have I muddied the water further?


On Thu, 27 Jun 2002, Corinna Vinschen wrote:

> On Thu, Jun 27, 2002 at 09:51:23AM -0400, Prentis Brooks wrote:
> > Thanks Corinna, I have already started looking at dll'izing the code.
> > Will be working on it through the weekend on a virtual machine as I
> > expect I will break things while trying to get it to work ;)  I expect I
> > should be able to have it working with inetd within a month or so
> > (giving time for work, moving, etc).   Once I have it working with
> > inetd, I will bundle it up and let you test with sshd.  I am not wanting
> > to dig through sshd for all the changes that may need to go there.
> 
> Prentis,
> 
> I don't quite understand what the dll has to do with inetd.  Since
> inetd is using tcpd, it's never linked against libwrap anyway.
> 
> It's actually not that hard.  If sshd is working when linked against
> the static lib, it very likely works using the dll.  You don't even
> have to change ssh's makefile since the Cygwin ld links against the
> dll first, if available.
> 
> However, I've found a problem when sshd is linked against tcp wrappers
> but AFAICS it's a flaw in Cygwin.
> 
> Corinna
> 
> 

-- 
Prentis Brooks	| prentis@aol.net | 703-265-0914 | AIM: PrentisBrooks
Senior System Administrator - Web Infrastructure & Security

       A knight is sworn to valor.  His heart knows only virtue.  His blade
       defends the helpless.  His word speaks only truth.  His wrath undoes
       the wicked. - the old code of Bowen, last of the dragonslayers