From owner-freebsd-security  Fri Oct 19  7:29:23 2001
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Date: Fri, 19 Oct 2001 15:29:19 +0100
To: security@freebsd.org
From: slamdunk <slamdunk@neophile.net>
Subject: Re: OT: Data Packet Filters?
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This is from another list, maybe it will work on BSD

echo 1 >/proc/sys/net/ipv4/icmp_echo_ignore_all

To make it permanent, bung it in /etc/rc.d/rc.network, with other similar
commands.

Lets us know how you get on.

Slammer


At 06:00 19/10/2001 -0700, you wrote:
>I'm hoping someone on this list will share his/her knowledge with me
>even though this is somewhat off-topic.  :)
>
>I am trying to deny ICMP echo reply packets on my 3Com 812 ADSL
>modem/router.  It appears that the only way to do this is to write a
>data filter.  The fields I need to determine are offset (bytes - which
>I thought was 36 for ICMP code), length (bytes - I thought 1), Masked
>(hex - appears that FF is to match data exactly), and data (hex - I
>thought 0x0 echo reply).
>
>Can anyone get me pointed in the right direction?  Any help or URLs
>will be most appreciated.
>
>Thanks!
>
>Drew
>
>
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