selftests: netfilter: add synproxy test

Simple test for synproxy feature, iperf3 should be intercepted
by synproxy netns, but connection should still succeed.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Florian Westphal 2022-02-04 14:02:33 +01:00 committed by Pablo Neira Ayuso
parent 7db788ad62
commit 7152303cbe
2 changed files with 116 additions and 1 deletions

View File

@ -6,7 +6,7 @@ TEST_PROGS := nft_trans_stress.sh nft_fib.sh nft_nat.sh bridge_brouter.sh \
nft_concat_range.sh nft_conntrack_helper.sh \
nft_queue.sh nft_meta.sh nf_nat_edemux.sh \
ipip-conntrack-mtu.sh conntrack_tcp_unreplied.sh \
conntrack_vrf.sh
conntrack_vrf.sh nft_synproxy.sh
LDLIBS = -lmnl
TEST_GEN_FILES = nf-queue

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@ -0,0 +1,115 @@
#!/bin/bash
# SPDX-License-Identifier: GPL-2.0
#
# Kselftest framework requirement - SKIP code is 4.
ksft_skip=4
ret=0
rnd=$(mktemp -u XXXXXXXX)
nsr="nsr-$rnd" # synproxy machine
ns1="ns1-$rnd" # iperf client
ns2="ns2-$rnd" # iperf server
checktool (){
if ! $1 > /dev/null 2>&1; then
echo "SKIP: Could not $2"
exit $ksft_skip
fi
}
checktool "nft --version" "run test without nft tool"
checktool "ip -Version" "run test without ip tool"
checktool "iperf3 --version" "run test without iperf3"
checktool "ip netns add $nsr" "create net namespace"
ip netns add $ns1
ip netns add $ns2
cleanup() {
ip netns pids $ns1 | xargs kill 2>/dev/null
ip netns pids $ns2 | xargs kill 2>/dev/null
ip netns del $ns1
ip netns del $ns2
ip netns del $nsr
}
trap cleanup EXIT
ip link add veth0 netns $nsr type veth peer name eth0 netns $ns1
ip link add veth1 netns $nsr type veth peer name eth0 netns $ns2
for dev in lo veth0 veth1; do
ip -net $nsr link set $dev up
done
ip -net $nsr addr add 10.0.1.1/24 dev veth0
ip -net $nsr addr add 10.0.2.1/24 dev veth1
ip netns exec $nsr sysctl -q net.ipv4.conf.veth0.forwarding=1
ip netns exec $nsr sysctl -q net.ipv4.conf.veth1.forwarding=1
ip netns exec $nsr sysctl -q net.netfilter.nf_conntrack_tcp_loose=0
for n in $ns1 $ns2; do
ip -net $n link set lo up
ip -net $n link set eth0 up
done
ip -net $ns1 addr add 10.0.1.99/24 dev eth0
ip -net $ns2 addr add 10.0.2.99/24 dev eth0
ip -net $ns1 route add default via 10.0.1.1
ip -net $ns2 route add default via 10.0.2.1
# test basic connectivity
if ! ip netns exec $ns1 ping -c 1 -q 10.0.2.99 > /dev/null; then
echo "ERROR: $ns1 cannot reach $ns2" 1>&2
exit 1
fi
if ! ip netns exec $ns2 ping -c 1 -q 10.0.1.99 > /dev/null; then
echo "ERROR: $ns2 cannot reach $ns1" 1>&2
exit 1
fi
ip netns exec $ns2 iperf3 -s > /dev/null 2>&1 &
# ip netns exec $nsr tcpdump -vvv -n -i veth1 tcp | head -n 10 &
sleep 1
ip netns exec $nsr nft -f - <<EOF
table inet filter {
chain prerouting {
type filter hook prerouting priority -300; policy accept;
meta iif veth0 tcp flags syn counter notrack
}
chain forward {
type filter hook forward priority 0; policy accept;
ct state new,established counter accept
meta iif veth0 meta l4proto tcp ct state untracked,invalid synproxy mss 1460 sack-perm timestamp
ct state invalid counter drop
# make ns2 unreachable w.o. tcp synproxy
tcp flags syn counter drop
}
}
EOF
if [ $? -ne 0 ]; then
echo "SKIP: Cannot add nft synproxy"
exit $ksft_skip
fi
ip netns exec $ns1 timeout 5 iperf3 -c 10.0.2.99 -n $((1 * 1024 * 1024)) > /dev/null
if [ $? -ne 0 ]; then
echo "FAIL: iperf3 returned an error" 1>&2
ret=$?
ip netns exec $nsr nft list ruleset
else
echo "PASS: synproxy connection successful"
fi
exit $ret