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 From:  Peter Allgeyer <allgeyer at web dot de>
 To:  m0n0wall dash dev at lists dot m0n0 dot ch
 Subject:  Bug in "Bypass firewall rules for traffic on the same interface"
 Date:  Thu, 02 Nov 2006 17:09:54 +0100
Hi,

I think, I've found a bug in static route filtering, bypassing firewall
rules for traffic on the same interface. The generated rules are:

@3 pass out quick on lnc0 from 172.31.252.0/22 to 172.16.0.0/16
@4 pass out quick on lnc0 from 172.16.0.0/16 to 172.31.252.0/22

[..]
@6 pass out quick on lnc0 from any to any keep state
[..]

@6 skip 2 in on lnc0 from any to 172.31.252.30/32
@7 pass in quick on lnc0 from 172.31.252.0/22 to 172.16.0.0/16
@8 pass in quick on lnc0 from 172.16.0.0/16 to 172.31.252.0/22

172.31.252/22 is the net m0n0 is in,
172.16.0.0/16 is an internal net
behind an internal router at 172.31.252.1.

I can reach any internal machine, but the reply packets are blocked by
m0n0 because of the incoming skip rule (see @6 skip 2 in on lnc0 ..).

Version  	1.22
Platform 	generic-pc-cdrom

Maybe it's fixed in 1.23b, so far I haven't looked at it.

BR, PIT

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