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From: Christian Seberino <seberino@spawar.navy.mil>
To: Patrick Schaaf <bof@bof.de>
Cc: netfilter@lists.samba.org
Subject: Re: how is this stuff getting thru default deny iptables firewall?....
Date: Tue, 9 Jul 2002 12:08:52 -0700	[thread overview]
Message-ID: <20020709120852.A24804@spawar.navy.mil> (raw)
In-Reply-To: <20020627093730.C1873@oknodo.bof.de>; from bof@bof.de on Thu, Jun 27, 2002 at 09:37:30AM +0200

> On the other hand, if there is not yet a conntrack record in existence
> for the packet, the nat PREROUTING table is consulted

Patrick

I appreciate all your help and after thinking about this on my vacation
last week I think I got it now thanks to your feedback!
Can I ask you few questions to verify I got what you said regarding
how a private LAN can use DNS, HTTP, SMTP, etc. thru an SSH-only firewall?...

My main confusion I believe was that packets associated with preexisting
conntracks are handled differently than packets *not* associated
with a previous conntrack.

Q1: The conntrack is the "memory" of netfilter that allows it to make
decisions based on "history" of PC traffic right?

Q2: Packets with a previous associated conntrack are handled *differently* than ones
without previous conntrack... and any attempt to try to understand
behavior of firewall *without* this concept is doomed
to confusion right?

Q3: Is conntrack a new "iptables only" feature? I imagine ancient ipchains/ipfwadmin
would have had same issues and therefore would need something like
"conntrack" to work correctly right?

Sincerely,

Chris
-- 
_______________________________________

Dr. Christian Seberino
SPAWAR Systems Center San Diego
Code 2363
53560 Hull Street
San Diego, CA 92152-5001
U.S.A.

Phone: (619) 553-7940
Fax:   (619) 553-2836
Email: seberino@spawar.navy.mil
_______________________________________


  reply	other threads:[~2002-07-09 19:08 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2002-06-22 17:30 how is this stuff getting thru default deny iptables firewall? Christian Seberino
2002-06-22 17:38 ` Antony Stone
2002-06-23  7:13   ` Christian Seberino
2002-06-23  7:53     ` Patrick Schaaf
2002-06-27  7:21       ` Christian Seberino
2002-06-27  7:37         ` Patrick Schaaf
2002-07-09 19:08           ` Christian Seberino [this message]
2002-06-23  8:07     ` Antony Stone
2002-06-27  7:14       ` Christian Seberino
2002-06-27  7:28         ` Patrick Schaaf
  -- strict thread matches above, loose matches on Subject: below --
2002-06-22 21:43 James T. Moore
2002-06-23  7:13 ` Christian Seberino
2002-07-09 19:43 j davis
2002-07-09 21:41 ` Christian Seberino
2002-07-09 21:43 ` Christian Seberino
     [not found]   ` <Pine.LNX.4.33.0207101903030.1723-100000@dodobirdy.nestac.com>
2002-07-10 16:34     ` Christian Seberino

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