tools/testing/selftests/net/forwarding/bridge_fdb_learning_limit.sh

#!/bin/bash
# SPDX-License-Identifier: GPL-2.0

# ShellCheck incorrectly believes that most of the code here is unreachable
# because it's invoked by variable name following ALL_TESTS.
#
# shellcheck disable=SC2317

ALL_TESTS="check_accounting check_limit"
NUM_NETIFS=6
source lib.sh

TEST_MAC_BASE=de:ad:be:ef:42:

NUM_PKTS=16
FDB_LIMIT=8

FDB_TYPES=(
	# name		is counted?	overrides learned?
	'learned	1		0'
	'static		0		1'
	'user		0		1'
	'extern_learn	0		1'
	'local		0		1'
)

mac()
{
	printf "${TEST_MAC_BASE}%02x" "$1"
}

H1_DEFAULT_MAC=$(mac 42)

switch_create()
{
	ip link add dev br0 type bridge

	ip link set dev "$swp1" master br0
	ip link set dev "$swp2" master br0
	# swp3 is used to add local MACs, so do not add it to the bridge yet.

	# swp2 is only used for replying when learning on swp1, its MAC should not be learned.
	ip link set dev "$swp2" type bridge_slave learning off

	ip link set dev br0 up

	ip link set dev "$swp1" up
	ip link set dev "$swp2" up
	ip link set dev "$swp3" up
}

switch_destroy()
{
	ip link set dev "$swp3" down
	ip link set dev "$swp2" down
	ip link set dev "$swp1" down

	ip link del dev br0
}

h_create()
{
	ip link set "$h1" addr "$H1_DEFAULT_MAC"

	simple_if_init "$h1" 192.0.2.1/24
	simple_if_init "$h2" 192.0.2.2/24
}

h_destroy()
{
	simple_if_fini "$h1" 192.0.2.1/24
	simple_if_fini "$h2" 192.0.2.2/24
}

setup_prepare()
{
	h1=${NETIFS[p1]}
	swp1=${NETIFS[p2]}

	h2=${NETIFS[p3]}
	swp2=${NETIFS[p4]}

	swp3=${NETIFS[p6]}

	vrf_prepare

	h_create

	switch_create
}

cleanup()
{
	pre_cleanup

	switch_destroy

	h_destroy

	vrf_cleanup
}

fdb_get_n_learned()
{
	ip -d -j link show dev br0 type bridge | \
		jq '.[]["linkinfo"]["info_data"]["fdb_n_learned"]'
}

fdb_get_n_mac()
{
	local mac=${1}

	bridge -j fdb show br br0 | \
		jq "map(select(.mac == \"${mac}\" and (has(\"vlan\") | not))) | length"
}

fdb_fill_learned()
{
	local i

	for i in $(seq 1 "$NUM_PKTS"); do
		fdb_add learned "$(mac "$i")"
	done
}

fdb_reset()
{
	bridge fdb flush dev br0

	# Keep the default MAC address of h1 in the table. We set it to a different one when
	# testing dynamic learning.
	bridge fdb add "$H1_DEFAULT_MAC" dev "$swp1" master static use
}

fdb_add()
{
	local type=$1 mac=$2

	case "$type" in
		learned)
			ip link set "$h1" addr "$mac"
			# Wait for a reply so we implicitly wait until after the forwarding
			# code finished and the FDB entry was created.
			PING_COUNT=1 ping_do "$h1" 192.0.2.2
			check_err $? "Failed to ping another bridge port"
			ip link set "$h1" addr "$H1_DEFAULT_MAC"
			;;
		local)
			ip link set dev "$swp3" addr "$mac" && ip link set "$swp3" master br0
			;;
		static)
			bridge fdb replace "$mac" dev "$swp1" master static
			;;
		user)
			bridge fdb replace "$mac" dev "$swp1" master static use
			;;
		extern_learn)
			bridge fdb replace "$mac" dev "$swp1" master extern_learn
			;;
	esac

	check_err $? "Failed to add a FDB entry of type ${type}"
}

fdb_del()
{
	local type=$1 mac=$2

	case "$type" in
		local)
			ip link set "$swp3" nomaster
			;;
		*)
			bridge fdb del "$mac" dev "$swp1" master
			;;
	esac

	check_err $? "Failed to remove a FDB entry of type ${type}"
}

check_fdb_n_learned_support()
{
	if ! ip link help bridge 2>&1 | grep -q "fdb_max_learned"; then
		echo "SKIP: iproute2 too old, missing bridge max learned support"
		exit $ksft_skip
	fi

	ip link add dev br0 type bridge
	local learned=$(fdb_get_n_learned)
	ip link del dev br0
	if [ "$learned" == "null" ]; then
		echo "SKIP: kernel too old; bridge fdb_n_learned feature not supported."
		exit $ksft_skip
	fi
}

check_accounting_one_type()
{
	local type=$1 is_counted=$2 overrides_learned=$3
	shift 3
	RET=0

	fdb_reset
	fdb_add "$type" "$(mac 0)"
	learned=$(fdb_get_n_learned)
	[ "$learned" -ne "$is_counted" ]
	check_fail $? "Inserted FDB type ${type}: Expected the count ${is_counted}, but got ${learned}"

	fdb_del "$type" "$(mac 0)"
	learned=$(fdb_get_n_learned)
	[ "$learned" -ne 0 ]
	check_fail $? "Removed FDB type ${type}: Expected the count 0, but got ${learned}"

	if [ "$overrides_learned" -eq 1 ]; then
		fdb_reset
		fdb_add learned "$(mac 0)"
		fdb_add "$type" "$(mac 0)"
		learned=$(fdb_get_n_learned)
		[ "$learned" -ne "$is_counted" ]
		check_fail $? "Set a learned entry to FDB type ${type}: Expected the count ${is_counted}, but got ${learned}"
		fdb_del "$type" "$(mac 0)"
	fi

	log_test "FDB accounting interacting with FDB type ${type}"
}

check_accounting()
{
	local type_args learned
	RET=0

	fdb_reset
	learned=$(fdb_get_n_learned)
	[ "$learned" -ne 0 ]
	check_fail $? "Flushed the FDB table: Expected the count 0, but got ${learned}"

	fdb_fill_learned
	sleep 1

	learned=$(fdb_get_n_learned)
	[ "$learned" -ne "$NUM_PKTS" ]
	check_fail $? "Filled the FDB table: Expected the count ${NUM_PKTS}, but got ${learned}"

	log_test "FDB accounting"

	for type_args in "${FDB_TYPES[@]}"; do
		# This is intentional use of word splitting.
		# shellcheck disable=SC2086
		check_accounting_one_type $type_args
	done
}

check_limit_one_type()
{
	local type=$1 is_counted=$2
	local n_mac expected=$((1 - is_counted))
	RET=0

	fdb_reset
	fdb_fill_learned

	fdb_add "$type" "$(mac 0)"
	n_mac=$(fdb_get_n_mac "$(mac 0)")
	[ "$n_mac" -ne "$expected" ]
	check_fail $? "Inserted FDB type ${type} at limit: Expected the count ${expected}, but got ${n_mac}"

	log_test "FDB limits interacting with FDB type ${type}"
}

check_limit()
{
	local learned
	RET=0

	ip link set br0 type bridge fdb_max_learned "$FDB_LIMIT"

	fdb_reset
	fdb_fill_learned

	learned=$(fdb_get_n_learned)
	[ "$learned" -ne "$FDB_LIMIT" ]
	check_fail $? "Filled the limited FDB table: Expected the count ${FDB_LIMIT}, but got ${learned}"

	log_test "FDB limits"

	for type_args in "${FDB_TYPES[@]}"; do
		# This is intentional use of word splitting.
		# shellcheck disable=SC2086
		check_limit_one_type $type_args
	done
}

check_fdb_n_learned_support

trap cleanup EXIT

setup_prepare

tests_run

exit $EXIT_STATUS