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From mauricio.campiglia@gmail.com Mon May 18 00:43:49 2009
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Sender: Mauricio Campiglia <mauricio.campiglia@gmail.com>
From: Mauricio Campiglia <mauricio@campiglia.org>
To: chalpin@cs.wisc.edu
Subject: Incorrect packet traversal path on your Netfilter page?
Date: Mon, 18 May 2009 00:34:03 -0300
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Corey,

I have come across your Netfilter page [0]. Thanks for letting people=20
understand Netfilter in a simple and straightforward way. I have,=20
nevertheless, a couple of diferences on wich, afaik, are the correct=20
traversal of packets.

Where you write:
forwarded
     nat/PREROUTING -> filter/FORWARD -> nat/OUTPUT -> nat/POSTROUTING=20
outgoing
     filter/OUTPUT -> nat/PREROUTING -> nat/OUTPUT -> nat/POSTROUTING

I think the correct flows are [1]:
forwarded
     nat/PREROUTING -> filter/FORWARD -> nat/POSTROUTING=20
outgoing
     nat/OUTPUT -> filter/OUTPUT -> nat/POSTROUTING

[0]http://pages.cs.wisc.edu/~chalpin/project/netfilter.html
[1]http://pub1.zcjh.tpc.edu.tw:9100/computer/Lists/Discussion/Attachments/1=
/PacketFlow.png

Regards,
      Mauricio Campiglia
=2D-=20
=C2=ABHistory is a vast early warning system.=C2=BB
         --Norman Cousins--

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