Re: not listening

In article <4g7vmcF1julblU2@xxxxxxxxxxxxxx>,
Sebastian Gottschalk <seppi@xxxxxxxxx> wrote:
Walter Roberson wrote:

Nothing listening for *new* connections on any port,
but you sure have something listening for returning packets.

Now would you please read RFC 793 and maybe also the POSIX standard to
clearly understand what "listening" means in terms of TCP/IP communication?

We have no reason to expect that the original poster is using a POSIX
compatible sockets -- for example it would be extremely reasonable to
suppose that the original poster might be using Microsoft Windows XP.

Oh noes, no POSIX for Windows !!!11
Now does this make a bind() and listen() work any different?

Darned if I know. Microsoft wrote their own IP stack as a subset
of their TDI interface. I don't have the patience to go through all the
microsoft documentation to find out whether microsoft's listen()
always has the same behaviour as POSIX.1's listen() .


Beside that, WinSrv03 R2 has got the POSIX subsystem back.

Well, since the original poster did not say anything about what
kind of system it is, I suppose there's a chance that it is
WinSrv03 R2, but since that's not a very common operating system,
if that prospect is to be seriously considered then so too should
be the possibility that some other OS (or some old Windows OS) is
present.


If you recheck you will find that the original poster did not
specify TCP/IP.

So, what else could you conclude to be consistent with the terms
"firewall" and "port", especially in comp.security.firewalls?

You already know my conclusion: that in the absense of information
that establishes that the OP is definitely running a secured system,
that the OP needs to be told "Yes, you may well need a firewall".

It should be the First Fundamental Theorem of comp.security.firewalls :
that a firewall is needed until the situation is proven safe. If
we are missing important information about the situation, then we
should not be telling anyone that they definitely do not need a firewall.
.

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