[PATCH net-next 6/7] selftests: forwarding: Add a test for TC trapping behavior

From: Petr Machata <petrm@nvidia.com>
To: <netdev@vger.kernel.org>
Cc: Petr Machata <petrm@nvidia.com>, Jiri Pirko <jiri@nvidia.com>,
	"David S. Miller" <davem@davemloft.net>,
	Jakub Kicinski <kuba@kernel.org>,
	Ido Schimmel <idosch@nvidia.com>,
	Cong Wang <xiyou.wangcong@gmail.com>,
	Jamal Hadi Salim <jhs@mojatatu.com>
Subject: [PATCH net-next 6/7] selftests: forwarding: Add a test for TC trapping behavior
Date: Thu, 8 Apr 2021 15:38:28 +0200	[thread overview]
Message-ID: <20210408133829.2135103-7-petrm@nvidia.com> (raw)
In-Reply-To: <20210408133829.2135103-1-petrm@nvidia.com>

Test that trapped packets are forwarded through the SW datapath, whereas
trap_fwd'd ones are not (but are forwarded through HW datapath). For
completeness' sake, also test that "pass" (i.e. lack of trapping) simply
forwards the packets in the HW datapath.

Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
---
 .../selftests/net/forwarding/tc_trap.sh       | 170 ++++++++++++++++++
 1 file changed, 170 insertions(+)
 create mode 100755 tools/testing/selftests/net/forwarding/tc_trap.sh

diff --git a/tools/testing/selftests/net/forwarding/tc_trap.sh b/tools/testing/selftests/net/forwarding/tc_trap.sh
new file mode 100755
index 000000000000..56336cea45a2
--- /dev/null
+++ b/tools/testing/selftests/net/forwarding/tc_trap.sh
@@ -0,0 +1,170 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+# In the following simple routing scenario, put SW datapath packet probes on
+# $swp1, $swp2 and $h2. Always expect packets to arrive at $h2. Depending on
+# whether, in the HW datapath, $swp1 lets packets pass, traps them, or
+# traps_forwards them, $swp1 and $swp2 probes are expected to give different
+# results.
+#
+# +----------------------+                             +----------------------+
+# | H1                   |                             |                   H2 |
+# |    + $h1             |                             |            $h2 +     |
+# |    | 192.0.2.1/28    |                             |  192.0.2.18/28 |     |
+# +----|-----------------+                             +----------------|-----+
+#      |                                                                |
+# +----|----------------------------------------------------------------|-----+
+# | SW |                                                                |     |
+# |    + $swp1                                                    $swp2 +     |
+# |      192.0.2.2/28                                     192.0.2.17/28       |
+# +---------------------------------------------------------------------------+
+
+
+ALL_TESTS="
+	no_trap_test
+	trap_fwd_test
+	trap_test
+"
+
+NUM_NETIFS=4
+source lib.sh
+source tc_common.sh
+
+h1_create()
+{
+	simple_if_init $h1 192.0.2.1/28
+	ip route add vrf v$h1 192.0.2.16/28 via 192.0.2.2
+}
+
+h1_destroy()
+{
+	ip route del vrf v$h1 192.0.2.16/28 via 192.0.2.2
+	simple_if_fini $h1 192.0.2.1/28
+}
+
+h2_create()
+{
+	simple_if_init $h2 192.0.2.18/28
+	ip route add vrf v$h2 192.0.2.0/28 via 192.0.2.17
+	tc qdisc add dev $h2 clsact
+}
+
+h2_destroy()
+{
+	tc qdisc del dev $h2 clsact
+	ip route del vrf v$h2 192.0.2.0/28 via 192.0.2.17
+	simple_if_fini $h2 192.0.2.18/28
+}
+
+switch_create()
+{
+	simple_if_init $swp1 192.0.2.2/28
+	__simple_if_init $swp2 v$swp1 192.0.2.17/28
+
+	tc qdisc add dev $swp1 clsact
+	tc qdisc add dev $swp2 clsact
+}
+
+switch_destroy()
+{
+	tc qdisc del dev $swp2 clsact
+	tc qdisc del dev $swp1 clsact
+
+	__simple_if_fini $swp2 192.0.2.17/28
+	simple_if_fini $swp1 192.0.2.2/28
+}
+
+setup_prepare()
+{
+	h1=${NETIFS[p1]}
+	swp1=${NETIFS[p2]}
+
+	swp2=${NETIFS[p3]}
+	h2=${NETIFS[p4]}
+
+	vrf_prepare
+	forwarding_enable
+
+	h1_create
+	h2_create
+	switch_create
+}
+
+cleanup()
+{
+	pre_cleanup
+
+	switch_destroy
+	h2_destroy
+	h1_destroy
+
+	forwarding_restore
+	vrf_cleanup
+}
+
+__test()
+{
+	local action=$1; shift
+	local ingress_should_fail=$1; shift
+	local egress_should_fail=$1; shift
+
+	tc filter add dev $swp1 ingress protocol ip pref 2 handle 101 \
+		flower skip_sw dst_ip 192.0.2.18 action $action
+	tc filter add dev $swp1 ingress protocol ip pref 1 handle 102 \
+		flower skip_hw dst_ip 192.0.2.18 action pass
+	tc filter add dev $swp2 egress protocol ip pref 1 handle 103 \
+		flower skip_hw dst_ip 192.0.2.18 action pass
+	tc filter add dev $h2 ingress protocol ip pref 1 handle 104 \
+		flower dst_ip 192.0.2.18 action drop
+
+	RET=0
+
+	$MZ $h1 -c 1 -p 64 -a $(mac_get $h1) -b $(mac_get $swp1) \
+		-A 192.0.2.1 -B 192.0.2.18 -q -t ip
+
+	tc_check_packets "dev $swp1 ingress" 102 1
+	check_err_fail $ingress_should_fail $? "ingress should_fail $ingress_should_fail"
+
+	tc_check_packets "dev $swp2 egress" 103 1
+	check_err_fail $egress_should_fail $? "egress should_fail $egress_should_fail"
+
+	tc_check_packets "dev $h2 ingress" 104 1
+	check_err $? "Did not see the packet on host"
+
+	log_test "$action test"
+
+	tc filter del dev $h2 ingress protocol ip pref 1 handle 104 flower
+	tc filter del dev $swp2 egress protocol ip pref 1 handle 103 flower
+	tc filter del dev $swp1 ingress protocol ip pref 1 handle 102 flower
+	tc filter del dev $swp1 ingress protocol ip pref 2 handle 101 flower
+}
+
+no_trap_test()
+{
+	__test pass 1 1
+}
+
+trap_fwd_test()
+{
+	__test trap_fwd 0 1
+}
+
+trap_test()
+{
+	__test trap 0 0
+}
+
+trap cleanup EXIT
+
+setup_prepare
+setup_wait
+
+if ! tc_offload_check; then
+	check_err 1 "Could not test offloaded functionality"
+	log_test "offloaded tc_trap test"
+	exit
+fi
+
+tests_run
+
+exit $EXIT_STATUS
-- 
2.26.2

