selftests: mlxsw: devlink_trap_tunnel_ipip6: Add test case for IPv6 decap_error

IPv6 underlay support was added, add test to check that "decap_error" trap
is triggered under the right conditions and that devlink counters increase.
Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tools/testing/selftests/drivers/net/mlxsw/spectrum-2/devlink_trap_tunnel_ipip6.sh

+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# Test devlink-trap tunnel exceptions functionality over mlxsw.
+# Check all exception traps to make sure they are triggered under the right
+# conditions.
+
+# +-------------------------+
+# | H1                      |
+# |               $h1 +     |
+# |  2001:db8:1::1/64 |     |
+# +-------------------|-----+
+#                     |
+# +-------------------|-----+
+# | SW1               |     |
+# |             $swp1 +     |
+# |  2001:db8:1::2/64       |
+# |                         |
+# |  + g1 (ip6gre)          |
+# |    loc=2001:db8:3::1    |
+# |    rem=2001:db8:3::2    |
+# |    tos=inherit          |
+# |                         |
+# |  + $rp1                 |
+# |  | 2001:db8:10::1/64    |
+# +--|----------------------+
+#    |
+# +--|----------------------+
+# |  |                 VRF2 |
+# |  + $rp2                 |
+# |    2001:db8:10::2/64    |
+# +-------------------------+
+
+lib_dir=$(dirname $0)/../../../../net/forwarding
+
+ALL_TESTS="
+	decap_error_test
+"
+
+NUM_NETIFS=4
+source $lib_dir/lib.sh
+source $lib_dir/tc_common.sh
+source $lib_dir/devlink_lib.sh
+
+h1_create()
+{
+	simple_if_init $h1 2001:db8:1::1/64
+}
+
+h1_destroy()
+{
+	simple_if_fini $h1 2001:db8:1::1/64
+}
+
+vrf2_create()
+{
+	simple_if_init $rp2 2001:db8:10::2/64
+}
+
+vrf2_destroy()
+{
+	simple_if_fini $rp2 2001:db8:10::2/64
+}
+
+switch_create()
+{
+	ip link set dev $swp1 up
+	__addr_add_del $swp1 add 2001:db8:1::2/64
+	tc qdisc add dev $swp1 clsact
+
+	tunnel_create g1 ip6gre 2001:db8:3::1 2001:db8:3::2 tos inherit \
+		ttl inherit
+	ip link set dev g1 up
+	__addr_add_del g1 add 2001:db8:3::1/128
+
+	ip link set dev $rp1 up
+	__addr_add_del $rp1 add 2001:db8:10::1/64
+}
+
+switch_destroy()
+{
+	__addr_add_del $rp1 del 2001:db8:10::1/64
+	ip link set dev $rp1 down
+
+	__addr_add_del g1 del 2001:db8:3::1/128
+	ip link set dev g1 down
+	tunnel_destroy g1
+
+	tc qdisc del dev $swp1 clsact
+	__addr_add_del $swp1 del 2001:db8:1::2/64
+	ip link set dev $swp1 down
+}
+
+setup_prepare()
+{
+	h1=${NETIFS[p1]}
+	swp1=${NETIFS[p2]}
+
+	rp1=${NETIFS[p3]}
+	rp2=${NETIFS[p4]}
+
+	forwarding_enable
+	vrf_prepare
+	h1_create
+	switch_create
+	vrf2_create
+}
+
+cleanup()
+{
+	pre_cleanup
+
+	vrf2_destroy
+	switch_destroy
+	h1_destroy
+	vrf_cleanup
+	forwarding_restore
+}
+
+ipip_payload_get()
+{
+	local saddr="20:01:0d:b8:00:02:00:00:00:00:00:00:00:00:00:01"
+	local daddr="20:01:0d:b8:00:01:00:00:00:00:00:00:00:00:00:01"
+	local flags=$1; shift
+	local key=$1; shift
+
+	p=$(:
+		)"$flags"$(		      : GRE flags
+	        )"0:00:"$(                    : Reserved + version
+		)"86:dd:"$(		      : ETH protocol type
+		)"$key"$( 		      : Key
+		)"6"$(	                      : IP version
+		)"0:0"$(		      : Traffic class
+		)"0:00:00:"$(		      : Flow label
+		)"00:00:"$(                   : Payload length
+		)"3a:"$(                      : Next header
+		)"04:"$(                      : Hop limit
+		)"$saddr:"$(                  : IP saddr
+		)"$daddr:"$(                  : IP daddr
+		)
+	echo $p
+}
+
+ecn_payload_get()
+{
+	echo $(ipip_payload_get "0")
+}
+
+ecn_decap_test()
+{
+	local trap_name="decap_error"
+	local desc=$1; shift
+	local ecn_desc=$1; shift
+	local outer_tos=$1; shift
+	local mz_pid
+
+	RET=0
+
+	tc filter add dev $swp1 egress protocol ipv6 pref 1 handle 101 \
+		flower src_ip 2001:db8:2::1 dst_ip 2001:db8:1::1 skip_sw \
+		action pass
+
+	rp1_mac=$(mac_get $rp1)
+	rp2_mac=$(mac_get $rp2)
+	payload=$(ecn_payload_get)
+
+	ip vrf exec v$rp2 $MZ -6 $rp2 -c 0 -d 1msec -a $rp2_mac -b $rp1_mac \
+		-A 2001:db8:3::2 -B 2001:db8:3::1 -t ip \
+			tos=$outer_tos,next=47,p=$payload -q &
+	mz_pid=$!
+
+	devlink_trap_exception_test $trap_name
+
+	tc_check_packets "dev $swp1 egress" 101 0
+	check_err $? "Packets were not dropped"
+
+	log_test "$desc: Inner ECN is not ECT and outer is $ecn_desc"
+
+	kill $mz_pid && wait $mz_pid &> /dev/null
+	tc filter del dev $swp1 egress protocol ipv6 pref 1 handle 101 flower
+}
+
+no_matching_tunnel_test()
+{
+	local trap_name="decap_error"
+	local desc=$1; shift
+	local sip=$1; shift
+	local mz_pid
+
+	RET=0
+
+	tc filter add dev $swp1 egress protocol ipv6 pref 1 handle 101 \
+		flower src_ip 2001:db8:2::1 dst_ip 2001:db8:1::1 action pass
+
+	rp1_mac=$(mac_get $rp1)
+	rp2_mac=$(mac_get $rp2)
+	payload=$(ipip_payload_get "$@")
+
+	ip vrf exec v$rp2 $MZ -6 $rp2 -c 0 -d 1msec -a $rp2_mac -b $rp1_mac \
+		-A $sip -B 2001:db8:3::1 -t ip next=47,p=$payload -q &
+	mz_pid=$!
+
+	devlink_trap_exception_test $trap_name
+
+	tc_check_packets "dev $swp1 egress" 101 0
+	check_err $? "Packets were not dropped"
+
+	log_test "$desc"
+
+	kill $mz_pid && wait $mz_pid &> /dev/null
+	tc filter del dev $swp1 egress protocol ipv6 pref 1 handle 101 flower
+}
+
+decap_error_test()
+{
+	# Correct source IP - the remote address
+	local sip=2001:db8:3::2
+
+	ecn_decap_test "Decap error" "ECT(1)" 01
+	ecn_decap_test "Decap error" "ECT(0)" 02
+	ecn_decap_test "Decap error" "CE" 03
+
+	no_matching_tunnel_test "Decap error: Source IP check failed" \
+		2001:db8:4::2 "0"
+	no_matching_tunnel_test \
+		"Decap error: Key exists but was not expected" $sip "2" \
+		"00:00:00:E9:"
+
+	# Destroy the tunnel and create new one with key
+	__addr_add_del g1 del 2001:db8:3::1/128
+	tunnel_destroy g1
+
+	tunnel_create g1 ip6gre 2001:db8:3::1 2001:db8:3::2 tos inherit \
+		ttl inherit key 233
+	__addr_add_del g1 add 2001:db8:3::1/128
+
+	no_matching_tunnel_test \
+		"Decap error: Key does not exist but was expected" $sip "0"
+	no_matching_tunnel_test \
+		"Decap error: Packet has a wrong key field" $sip "2" \
+		"00:00:00:E8:"
+}
+
+trap cleanup EXIT
+
+setup_prepare
+setup_wait
+tests_run
+
+exit $EXIT_STATUS