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From: "Jorge Dávila" <jorgedavilalopez@gmail.com>
To: netfilter@vger.kernel.org
Subject: Re: Correct Chains to Apply Rules
Date: Tue, 17 May 2011 16:06:32 -0600	[thread overview]
Message-ID: <BANLkTi=HLSfceXiVuEc45QHQOPd0ebFCPg@mail.gmail.com> (raw)
In-Reply-To: <1305669045.20717.1453045045@webmail.messagingengine.com>

Incoming traffic to eth0 or eth1 can be directed to the box itself or
must be FORWARDed in the case of:

1) Incoming traffic on eth0 directed to the internal network
2) Incoming traffic on eth1 directed to Internet

Jorge.

On Tue, May 17, 2011 at 3:50 PM,  <netfilter@buglecreek.com> wrote:
> OK.  Thanks.  So to block/allow traffic from network A to/from network B
> I would apply my rules to the FORWARD chain using a source/destination.
> The INPUT and OUTPUT chains on eth0 and eth1 are only for traffic bound
> for the firewall/router box itself?
>
> On Tue, 17 May 2011 23:29 +0200, "Pascal Hambourg"
> <pascal.mail@plouf.fr.eu.org> wrote:
>> Hello,
>>
>> netfilter@buglecreek.com a écrit :
>> >
>> > In the following scenario.  Someone makes a new HTTP request from the
>> > Internet that is allowed inbound on eth0 and goes out of the eth1
>> > interface to the HTTP server in the server network.
>> > The HTTP server in the server network sends the response to the original
>> > requester.
>> >
>> > Does the response ever hit the INPUT chain of ETH1?
>>
>> No.
>>
>> > Or does it immediately go to the FORWARD chain
>>
>> Yes.
>>
>> > and out the OUTPUT chain of eth0.
>>
>> No.
>> The three filter chains are mutually exclusive : a packet can only go
>> through one of them. Forwarded packets only go through the FORWARD chain.
>>
> --
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-- 
Jorge Isaac Dávila López
+505 8430 5462
jorgedavilalopez@gmail.com
---

  reply	other threads:[~2011-05-17 22:06 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-05-17 21:14 Correct Chains to Apply Rules netfilter
2011-05-17 21:29 ` Pascal Hambourg
2011-05-17 21:50   ` netfilter
2011-05-17 22:06     ` Jorge Dávila [this message]
2011-05-17 22:19     ` Andrew Beverley

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