[net-next,v2,13/14] selftests: devlink_trap: Add test cases for devlink-trap

diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile
index 0bd6b23c97ef..4ea59bf4eeec 100644
--- a/tools/testing/selftests/net/Makefile
+++ b/tools/testing/selftests/net/Makefile
@@ -10,7 +10,7 @@  TEST_PROGS += fib_tests.sh fib-onlink-tests.sh pmtu.sh udpgso.sh ip_defrag.sh
 TEST_PROGS += udpgso_bench.sh fib_rule_tests.sh msg_zerocopy.sh psock_snd.sh
 TEST_PROGS += udpgro_bench.sh udpgro.sh test_vxlan_under_vrf.sh reuseport_addr_any.sh
 TEST_PROGS += test_vxlan_fdb_changelink.sh so_txtime.sh ipv6_flowlabel.sh
-TEST_PROGS += tcp_fastopen_backup_key.sh fcnal-test.sh l2tp.sh
+TEST_PROGS += tcp_fastopen_backup_key.sh fcnal-test.sh l2tp.sh devlink_trap.sh
 TEST_PROGS_EXTENDED := in_netns.sh
 TEST_GEN_FILES =  socket nettest
 TEST_GEN_FILES += psock_fanout psock_tpacket msg_zerocopy reuseport_addr_any
diff --git a/tools/testing/selftests/net/config b/tools/testing/selftests/net/config
index b8503a8119b0..ddd400fd5dce 100644
--- a/tools/testing/selftests/net/config
+++ b/tools/testing/selftests/net/config
@@ -29,3 +29,4 @@  CONFIG_NET_SCH_FQ=m
 CONFIG_NET_SCH_ETF=m
 CONFIG_TEST_BLACKHOLE_DEV=m
 CONFIG_KALLSYMS=y
+CONFIG_NETDEVSIM=y
diff --git a/tools/testing/selftests/net/devlink_trap.sh b/tools/testing/selftests/net/devlink_trap.sh
new file mode 100755
index 000000000000..577bbd6c9411
--- /dev/null
+++ b/tools/testing/selftests/net/devlink_trap.sh
@@ -0,0 +1,616 @@ 
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# This test is for checking devlink-trap functionality. It makes use of
+# netdevsim which implements the required callbacks.
+
+##############################################################################
+# Global variables
+
+# Kselftest framework requirement - SKIP code is 4.
+KSFT_SKIP=4
+# Exit status to return at the end. Set in case one of the tests fails.
+EXIT_STATUS=0
+# Per-test return value. Clear at the beginning of each test.
+RET=0
+
+# netdevsim-specific variables.
+NETDEVSIM_PATH=/sys/bus/netdevsim/
+DEV_ADDR=1337
+SLEEP_TIME=.3
+DEVLINK_DEV=""
+NETDEV=""
+DEV=""
+
+##############################################################################
+# Dependencies
+
+if [ "$(id -u)" -ne 0 ]; then
+	echo "SKIP: Need root privileges"
+	exit $KSFT_SKIP
+fi
+
+if [ ! -d "$NETDEVSIM_PATH" ]; then
+	echo "SKIP: No netdevsim support"
+	exit $KSFT_SKIP
+fi
+
+if [ -d "${NETDEVSIM_PATH}/devices/netdevsim${DEV_ADDR}" ]; then
+	echo "SKIP: Device netdevsim${DEV_ADDR} already exists"
+	exit $KSFT_SKIP
+fi
+
+if [ ! -x "$(command -v jq)" ]; then
+	echo "SKIP: Could not run test without jq tool"
+	exit $KSFT_SKIP
+fi
+
+if [ ! -x "$(command -v udevadm)" ]; then
+	echo "SKIP: Could not run test without udevadm tool"
+	exit $KSFT_SKIP
+fi
+
+if [ ! -x "$(command -v ip)" ]; then
+	echo "SKIP: Could not run test without ip tool"
+	exit $KSFT_SKIP
+fi
+
+if [ ! -x "$(command -v devlink)" ]; then
+	echo "SKIP: Could not run test without devlink tool"
+	exit $KSFT_SKIP
+fi
+
+devlink help 2>&1 | grep -q "trap"
+if [ $? -ne 0 ]; then
+	echo "SKIP: iproute2 too old, missing devlink-trap"
+	exit $KSFT_SKIP
+fi
+
+##############################################################################
+# Helpers
+
+check_err()
+{
+	local err=$1; shift
+	local msg=$1; shift
+
+	if [[ $RET -eq 0 && $err -ne 0 ]]; then
+		RET=$err
+		RETMSG=$msg
+	fi
+}
+
+check_fail()
+{
+	local err=$1; shift
+	local msg=$1; shift
+
+	if [[ $RET -eq 0 && $err -eq 0 ]]; then
+		RET=1
+		RETMSG=$msg
+	fi
+}
+
+log_test()
+{
+	local test_name=$1
+	local opt_str=$2
+
+	if [[ $# -eq 2 ]]; then
+		opt_str="($opt_str)"
+	fi
+
+	if [[ $RET -ne 0 ]]; then
+		EXIT_STATUS=1
+		printf "TEST: %-60s  [FAIL]\n" "$test_name $opt_str"
+		if [[ ! -z "$RETMSG" ]]; then
+			printf "\t%s\n" "$RETMSG"
+		fi
+		return 1
+	fi
+
+	printf "TEST: %-60s  [ OK ]\n" "$test_name $opt_str"
+	return 0
+}
+
+netdevsim_dev_create()
+{
+	echo "$DEV_ADDR 0" > ${NETDEVSIM_PATH}/new_device
+}
+
+netdevsim_dev_destroy()
+{
+	echo "$DEV_ADDR" > ${NETDEVSIM_PATH}/del_device
+}
+
+netdevsim_port_create()
+{
+	echo 1 > ${NETDEVSIM_PATH}/devices/${DEV}/new_port
+}
+
+netdevsim_port_destroy()
+{
+	echo 1 > ${NETDEVSIM_PATH}/devices/${DEV}/del_port
+}
+
+##############################################################################
+# Trap helpers
+
+devlink_traps_num_get()
+{
+	devlink -j trap | jq '.[]["'$DEVLINK_DEV'"] | length'
+}
+
+devlink_traps_get()
+{
+	devlink -j trap | jq -r '.[]["'$DEVLINK_DEV'"][].name'
+}
+
+devlink_trap_type_get()
+{
+	local trap_name=$1; shift
+
+	devlink -j trap show $DEVLINK_DEV trap $trap_name \
+		| jq -r '.[][][].type'
+}
+
+devlink_trap_action_set()
+{
+	local trap_name=$1; shift
+	local action=$1; shift
+
+	# Pipe output to /dev/null to avoid expected warnings.
+	devlink trap set $DEVLINK_DEV trap $trap_name \
+		action $action &> /dev/null
+}
+
+devlink_trap_action_get()
+{
+	local trap_name=$1; shift
+
+	devlink -j trap show $DEVLINK_DEV trap $trap_name \
+		| jq -r '.[][][].action'
+}
+
+devlink_trap_group_get()
+{
+	devlink -j trap show $DEVLINK_DEV trap $trap_name \
+		| jq -r '.[][][].group'
+}
+
+devlink_trap_metadata_test()
+{
+	local trap_name=$1; shift
+	local metadata=$1; shift
+
+	devlink -jv trap show $DEVLINK_DEV trap $trap_name \
+		| jq -e '.[][][].metadata | contains(["'$metadata'"])' \
+		&> /dev/null
+}
+
+devlink_trap_rx_packets_get()
+{
+	local trap_name=$1; shift
+
+	devlink -js trap show $DEVLINK_DEV trap $trap_name \
+		| jq '.[][][]["stats"]["rx"]["packets"]'
+}
+
+devlink_trap_rx_bytes_get()
+{
+	local trap_name=$1; shift
+
+	devlink -js trap show $DEVLINK_DEV trap $trap_name \
+		| jq '.[][][]["stats"]["rx"]["bytes"]'
+}
+
+devlink_trap_stats_idle_test()
+{
+	local trap_name=$1; shift
+	local t0_packets t0_bytes
+	local t1_packets t1_bytes
+
+	t0_packets=$(devlink_trap_rx_packets_get $trap_name)
+	t0_bytes=$(devlink_trap_rx_bytes_get $trap_name)
+
+	sleep $SLEEP_TIME
+
+	t1_packets=$(devlink_trap_rx_packets_get $trap_name)
+	t1_bytes=$(devlink_trap_rx_bytes_get $trap_name)
+
+	if [[ $t0_packets -eq $t1_packets && $t0_bytes -eq $t1_bytes ]]; then
+		return 0
+	else
+		return 1
+	fi
+}
+
+devlink_traps_enable_all()
+{
+	local trap_name
+
+	for trap_name in $(devlink_traps_get); do
+		devlink_trap_action_set $trap_name "trap"
+	done
+}
+
+devlink_traps_disable_all()
+{
+	for trap_name in $(devlink_traps_get); do
+		devlink_trap_action_set $trap_name "drop"
+	done
+}
+
+##############################################################################
+# Trap group helpers
+
+devlink_trap_groups_get()
+{
+	devlink -j trap group | jq -r '.[]["'$DEVLINK_DEV'"][].name'
+}
+
+devlink_trap_group_action_set()
+{
+	local group_name=$1; shift
+	local action=$1; shift
+
+	# Pipe output to /dev/null to avoid expected warnings.
+	devlink trap group set $DEVLINK_DEV group $group_name action $action \
+		&> /dev/null
+}
+
+devlink_trap_group_rx_packets_get()
+{
+	local group_name=$1; shift
+
+	devlink -js trap group show $DEVLINK_DEV group $group_name \
+		| jq '.[][][]["stats"]["rx"]["packets"]'
+}
+
+devlink_trap_group_rx_bytes_get()
+{
+	local group_name=$1; shift
+
+	devlink -js trap group show $DEVLINK_DEV group $group_name \
+		| jq '.[][][]["stats"]["rx"]["bytes"]'
+}
+
+devlink_trap_group_stats_idle_test()
+{
+	local group_name=$1; shift
+	local t0_packets t0_bytes
+	local t1_packets t1_bytes
+
+	t0_packets=$(devlink_trap_group_rx_packets_get $group_name)
+	t0_bytes=$(devlink_trap_group_rx_bytes_get $group_name)
+
+	sleep $SLEEP_TIME
+
+	t1_packets=$(devlink_trap_group_rx_packets_get $group_name)
+	t1_bytes=$(devlink_trap_group_rx_bytes_get $group_name)
+
+	if [[ $t0_packets -eq $t1_packets && $t0_bytes -eq $t1_bytes ]]; then
+		return 0
+	else
+		return 1
+	fi
+}
+
+##############################################################################
+# Initialization
+
+setup_prepare()
+{
+	local netdev
+
+	DEV=netdevsim${DEV_ADDR}
+	DEVLINK_DEV=netdevsim/${DEV}
+
+	netdevsim_dev_create
+
+	if [ ! -d "${NETDEVSIM_PATH}/devices/${DEV}" ]; then
+		echo "Failed to create netdevsim device"
+		exit 1
+	fi
+
+	netdevsim_port_create
+
+	if [ ! -d "${NETDEVSIM_PATH}/devices/${DEV}/net/" ]; then
+		echo "Failed to create netdevsim port"
+		exit 1
+	fi
+
+	# Wait for udev to rename newly created netdev.
+	udevadm settle
+
+	NETDEV=$(ls ${NETDEVSIM_PATH}/devices/${DEV}/net/)
+}
+
+cleanup()
+{
+	netdevsim_port_destroy
+	netdevsim_dev_destroy
+}
+
+##############################################################################
+# Tests
+
+init_test()
+{
+	RET=0
+
+	test $(devlink_traps_num_get) -ne 0
+	check_err $? "No traps were registered"
+
+	log_test "Initialization"
+}
+
+trap_action_test()
+{
+	local orig_action
+	local trap_name
+	local action
+
+	RET=0
+
+	for trap_name in $(devlink_traps_get); do
+		# The action of non-drop traps cannot be changed.
+		if [ $(devlink_trap_type_get $trap_name) = "drop" ]; then
+			devlink_trap_action_set $trap_name "trap"
+			action=$(devlink_trap_action_get $trap_name)
+			if [ $action != "trap" ]; then
+				check_err 1 "Trap $trap_name did not change action to trap"
+			fi
+
+			devlink_trap_action_set $trap_name "drop"
+			action=$(devlink_trap_action_get $trap_name)
+			if [ $action != "drop" ]; then
+				check_err 1 "Trap $trap_name did not change action to drop"
+			fi
+		else
+			orig_action=$(devlink_trap_action_get $trap_name)
+
+			devlink_trap_action_set $trap_name "trap"
+			action=$(devlink_trap_action_get $trap_name)
+			if [ $action != $orig_action ]; then
+				check_err 1 "Trap $trap_name changed action when should not"
+			fi
+
+			devlink_trap_action_set $trap_name "drop"
+			action=$(devlink_trap_action_get $trap_name)
+			if [ $action != $orig_action ]; then
+				check_err 1 "Trap $trap_name changed action when should not"
+			fi
+		fi
+	done
+
+	log_test "Trap action"
+}
+
+trap_metadata_test()
+{
+	local trap_name
+
+	RET=0
+
+	for trap_name in $(devlink_traps_get); do
+		devlink_trap_metadata_test $trap_name "input_port"
+		check_err $? "Input port not reported as metadata of trap $trap_name"
+	done
+
+	log_test "Trap metadata"
+}
+
+bad_trap_test()
+{
+	RET=0
+
+	devlink_trap_action_set "made_up_trap" "drop"
+	check_fail $? "Did not get an error for non-existing trap"
+
+	log_test "Non-existing trap"
+}
+
+bad_trap_action_test()
+{
+	local traps_arr
+	local trap_name
+
+	RET=0
+
+	# Pick first trap.
+	traps_arr=($(devlink_traps_get))
+	trap_name=${traps_arr[0]}
+
+	devlink_trap_action_set $trap_name "made_up_action"
+	check_fail $? "Did not get an error for non-existing trap action"
+
+	log_test "Non-existing trap action"
+}
+
+trap_stats_test()
+{
+	local trap_name
+
+	RET=0
+
+	for trap_name in $(devlink_traps_get); do
+		devlink_trap_stats_idle_test $trap_name
+		check_err $? "Stats of trap $trap_name not idle when netdev down"
+
+		ip link set dev $NETDEV up
+
+		if [ $(devlink_trap_type_get $trap_name) = "drop" ]; then
+			devlink_trap_action_set $trap_name "trap"
+			devlink_trap_stats_idle_test $trap_name
+			check_fail $? "Stats of trap $trap_name idle when action is trap"
+
+			devlink_trap_action_set $trap_name "drop"
+			devlink_trap_stats_idle_test $trap_name
+			check_err $? "Stats of trap $trap_name not idle when action is drop"
+		else
+			devlink_trap_stats_idle_test $trap_name
+			check_fail $? "Stats of non-drop trap $trap_name idle when should not"
+		fi
+
+		ip link set dev $NETDEV down
+	done
+
+	log_test "Trap statistics"
+}
+
+trap_group_action_test()
+{
+	local curr_group group_name
+	local trap_name
+	local trap_type
+	local action
+
+	RET=0
+
+	for group_name in $(devlink_trap_groups_get); do
+		devlink_trap_group_action_set $group_name "trap"
+
+		for trap_name in $(devlink_traps_get); do
+			curr_group=$(devlink_trap_group_get $trap_name)
+			if [ $curr_group != $group_name ]; then
+				continue
+			fi
+
+			trap_type=$(devlink_trap_type_get $trap_name)
+			if [ $trap_type != "drop" ]; then
+				continue
+			fi
+
+			action=$(devlink_trap_action_get $trap_name)
+			if [ $action != "trap" ]; then
+				check_err 1 "Trap $trap_name did not change action to trap"
+			fi
+		done
+
+		devlink_trap_group_action_set $group_name "drop"
+
+		for trap_name in $(devlink_traps_get); do
+			curr_group=$(devlink_trap_group_get $trap_name)
+			if [ $curr_group != $group_name ]; then
+				continue
+			fi
+
+			trap_type=$(devlink_trap_type_get $trap_name)
+			if [ $trap_type != "drop" ]; then
+				continue
+			fi
+
+			action=$(devlink_trap_action_get $trap_name)
+			if [ $action != "drop" ]; then
+				check_err 1 "Trap $trap_name did not change action to drop"
+			fi
+		done
+	done
+
+	log_test "Trap group action"
+}
+
+bad_trap_group_test()
+{
+	RET=0
+
+	devlink_trap_group_action_set "made_up_trap_group" "drop"
+	check_fail $? "Did not get an error for non-existing trap group"
+
+	log_test "Non-existing trap group"
+}
+
+trap_group_stats_test()
+{
+	local group_name
+
+	RET=0
+
+	for group_name in $(devlink_trap_groups_get); do
+		devlink_trap_group_stats_idle_test $group_name
+		check_err $? "Stats of trap group $group_name not idle when netdev down"
+
+		ip link set dev $NETDEV up
+
+		devlink_trap_group_action_set $group_name "trap"
+		devlink_trap_group_stats_idle_test $group_name
+		check_fail $? "Stats of trap group $group_name idle when action is trap"
+
+		devlink_trap_group_action_set $group_name "drop"
+		ip link set dev $NETDEV down
+	done
+
+	log_test "Trap group statistics"
+}
+
+port_del_test()
+{
+	local group_name
+	local i
+
+	# The test never fails. It is meant to exercise different code paths
+	# and make sure we properly dismantle a port while packets are
+	# in-flight.
+	RET=0
+
+	devlink_traps_enable_all
+
+	for i in $(seq 1 10); do
+		ip link set dev $NETDEV up
+
+		sleep $SLEEP_TIME
+
+		netdevsim_port_destroy
+		netdevsim_port_create
+		udevadm settle
+	done
+
+	devlink_traps_disable_all
+
+	log_test "Port delete"
+}
+
+dev_del_test()
+{
+	local group_name
+	local i
+
+	# The test never fails. It is meant to exercise different code paths
+	# and make sure we properly unregister traps while packets are
+	# in-flight.
+	RET=0
+
+	devlink_traps_enable_all
+
+	for i in $(seq 1 10); do
+		ip link set dev $NETDEV up
+
+		sleep $SLEEP_TIME
+
+		cleanup
+		setup_prepare
+	done
+
+	devlink_traps_disable_all
+
+	log_test "Device delete"
+}
+
+trap cleanup EXIT
+
+# Each test should make sure that initial state is resumed at the end.
+setup_prepare
+init_test
+trap_action_test
+trap_metadata_test
+bad_trap_test
+bad_trap_action_test
+trap_stats_test
+trap_group_action_test
+bad_trap_group_test
+trap_group_stats_test
+port_del_test
+dev_del_test
+
+exit $EXIT_STATUS