Simple test for synproxy feature, iperf3 should be intercepted
by synproxy netns, but connection should still succeed.
Signed-off-by: Florian Westphal <fw@xxxxxxxxx>
---
tools/testing/selftests/netfilter/Makefile | 2 +-
.../selftests/netfilter/nft_synproxy.sh | 115 ++++++++++++++++++
2 files changed, 116 insertions(+), 1 deletion(-)
create mode 100755 tools/testing/selftests/netfilter/nft_synproxy.sh
diff --git a/tools/testing/selftests/netfilter/Makefile b/tools/testing/selftests/netfilter/Makefile
index ffca314897c4..e4f845dd942b 100644
--- a/tools/testing/selftests/netfilter/Makefile
+++ b/tools/testing/selftests/netfilter/Makefile
@@ -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
diff --git a/tools/testing/selftests/netfilter/nft_synproxy.sh b/tools/testing/selftests/netfilter/nft_synproxy.sh
new file mode 100755
index 000000000000..09bb95c87198
--- /dev/null
+++ b/tools/testing/selftests/netfilter/nft_synproxy.sh
@@ -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
--
2.34.1
