Messages in this thread | | | Date | Mon, 24 May 2004 16:41:32 +0200 | From | Christoph Pleger <> | Subject | iptables and bootp |
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Hello,
I'm using the following commands to drop all traffic to and from the bootp-port of one of my machines:
iptables -I INPUT -i eth0 -p tcp --destination-port bootps -j DROP iptables -I INPUT -i eth0 -p udp --destination-port bootps -j DROP iptables -I OUTPUT -o eth0 -p tcp --source-port bootps -j DROP iptables -I OUTPUT -o eth0 -p udp --source-port bootps -j DROP
But this machine gives a reply to another machine's bootp-request that was created by the program "bootpc" (it is not possible that that answer comes from another bootp-Server). Iptables-Statistics show that UDP-packets to the bootps-port have been dropped, but obviously that has not really happened (as shown by tcpdump). Dropped outgoing packets from port bootps do not appear in the statistics.
When I change the port number in the above commands (for example, to 20003), the packets are actually blocked.
Does somebody have any advice?
Kind regards Christoph Pleger - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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