iproute2/examples/SYN-DoS.rate.limit
2004-04-15 20:56:59 +00:00

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#! /bin/sh -x
#
# sample script on using the ingress capabilities
# this script shows how one can rate limit incoming SYNs
# Useful for TCP-SYN attack protection. You can use
# IPchains to have more powerful additions to the SYN (eg
# in addition the subnet)
#
#path to various utilities;
#change to reflect yours.
#
IPROUTE=/root/DS-6-beta/iproute2-990530-dsing
TC=$IPROUTE/tc/tc
IP=$IPROUTE/ip/ip
IPCHAINS=/root/DS-6-beta/ipchains-1.3.9/ipchains
INDEV=eth2
#
# tag all incoming SYN packets through $INDEV as mark value 1
############################################################
$IPCHAINS -A input -i $INDEV -y -m 1
############################################################
#
# install the ingress qdisc on the ingress interface
############################################################
$TC qdisc add dev $INDEV handle ffff: ingress
############################################################
#
#
# SYN packets are 40 bytes (320 bits) so three SYNs equals
# 960 bits (approximately 1kbit); so we rate limit below
# the incoming SYNs to 3/sec (not very sueful really; but
#serves to show the point - JHS
############################################################
$TC filter add dev $INDEV parent ffff: protocol ip prio 50 handle 1 fw \
police rate 1kbit burst 40 mtu 9k drop flowid :1
############################################################
#
echo "---- qdisc parameters Ingress ----------"
$TC qdisc ls dev $INDEV
echo "---- Class parameters Ingress ----------"
$TC class ls dev $INDEV
echo "---- filter parameters Ingress ----------"
$TC filter ls dev $INDEV parent ffff:
#deleting the ingress qdisc
#$TC qdisc del $INDEV ingress