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

# +-------------------------+
# |  H1                     |
# |               $h1 +     |
# |      192.0.2.2/24 |     |
# |  2001:db8:1::2/64 |     |
# +-------------------|-----+
#                     |
# +-------------------|----------------------+
# |                   |                   R1 |
# |             $rp11 +                      |
# |      192.0.2.1/24                        |
# |  2001:db8:1::1/64                        |
# |                                          |
# |  + $rp12              + $rp13            |
# |  | 169.254.2.12/24    | 169.254.3.13/24  |
# |  | fe80:2::12/64      | fe80:3::13/64    |
# +--|--------------------|------------------+
#    |                    |
# +--|--------------------|------------------+
# |  + $rp22              + $rp23            |
# |    169.254.2.22/24      169.254.3.23/24  |
# |    fe80:2::22/64        fe80:3::23/64    |
# |                                          |
# |             $rp21 +                      |
# |   198.51.100.1/24 |                      |
# |  2001:db8:2::1/64 |                   R2 |
# +-------------------|----------------------+
#                     |
# +-------------------|-----+
# |                   |     |
# |               $h2 +     |
# |   198.51.100.2/24       |
# |  2001:db8:2::2/64    H2 |
# +-------------------------+

ALL_TESTS="
	ping_ipv4
	ping_ipv6
	multipath_test
	nh_stats_test_v4
	nh_stats_test_v6
"
NUM_NETIFS=8
source lib.sh
source router_mpath_nh_lib.sh

h1_create()
{
	vrf_create "vrf-h1"
	ip link set dev $h1 master vrf-h1

	ip link set dev vrf-h1 up
	ip link set dev $h1 up

	ip address add 192.0.2.2/24 dev $h1
	ip address add 2001:db8:1::2/64 dev $h1

	ip route add 198.51.100.0/24 vrf vrf-h1 nexthop via 192.0.2.1
	ip route add 2001:db8:2::/64 vrf vrf-h1 nexthop via 2001:db8:1::1
}

h1_destroy()
{
	ip route del 2001:db8:2::/64 vrf vrf-h1
	ip route del 198.51.100.0/24 vrf vrf-h1

	ip address del 2001:db8:1::2/64 dev $h1
	ip address del 192.0.2.2/24 dev $h1

	ip link set dev $h1 down
	vrf_destroy "vrf-h1"
}

h2_create()
{
	vrf_create "vrf-h2"
	ip link set dev $h2 master vrf-h2

	ip link set dev vrf-h2 up
	ip link set dev $h2 up

	ip address add 198.51.100.2/24 dev $h2
	ip address add 2001:db8:2::2/64 dev $h2

	ip route add 192.0.2.0/24 vrf vrf-h2 nexthop via 198.51.100.1
	ip route add 2001:db8:1::/64 vrf vrf-h2 nexthop via 2001:db8:2::1
}

h2_destroy()
{
	ip route del 2001:db8:1::/64 vrf vrf-h2
	ip route del 192.0.2.0/24 vrf vrf-h2

	ip address del 2001:db8:2::2/64 dev $h2
	ip address del 198.51.100.2/24 dev $h2

	ip link set dev $h2 down
	vrf_destroy "vrf-h2"
}

router1_create()
{
	vrf_create "vrf-r1"
	ip link set dev $rp11 master vrf-r1
	ip link set dev $rp12 master vrf-r1
	ip link set dev $rp13 master vrf-r1

	ip link set dev vrf-r1 up
	ip link set dev $rp11 up
	ip link set dev $rp12 up
	ip link set dev $rp13 up

	ip address add 192.0.2.1/24 dev $rp11
	ip address add 2001:db8:1::1/64 dev $rp11

	ip address add 169.254.2.12/24 dev $rp12
	ip address add fe80:2::12/64 dev $rp12

	ip address add 169.254.3.13/24 dev $rp13
	ip address add fe80:3::13/64 dev $rp13
}

router1_destroy()
{
	ip route del 2001:db8:2::/64 vrf vrf-r1
	ip route del 198.51.100.0/24 vrf vrf-r1

	ip address del fe80:3::13/64 dev $rp13
	ip address del 169.254.3.13/24 dev $rp13

	ip address del fe80:2::12/64 dev $rp12
	ip address del 169.254.2.12/24 dev $rp12

	ip address del 2001:db8:1::1/64 dev $rp11
	ip address del 192.0.2.1/24 dev $rp11

	ip nexthop del id 103
	ip nexthop del id 101
	ip nexthop del id 102
	ip nexthop del id 106
	ip nexthop del id 104
	ip nexthop del id 105

	ip link set dev $rp13 down
	ip link set dev $rp12 down
	ip link set dev $rp11 down

	vrf_destroy "vrf-r1"
}

router2_create()
{
	vrf_create "vrf-r2"
	ip link set dev $rp21 master vrf-r2
	ip link set dev $rp22 master vrf-r2
	ip link set dev $rp23 master vrf-r2

	ip link set dev vrf-r2 up
	ip link set dev $rp21 up
	ip link set dev $rp22 up
	ip link set dev $rp23 up

	ip address add 198.51.100.1/24 dev $rp21
	ip address add 2001:db8:2::1/64 dev $rp21

	ip address add 169.254.2.22/24 dev $rp22
	ip address add fe80:2::22/64 dev $rp22

	ip address add 169.254.3.23/24 dev $rp23
	ip address add fe80:3::23/64 dev $rp23
}

router2_destroy()
{
	ip route del 2001:db8:1::/64 vrf vrf-r2
	ip route del 192.0.2.0/24 vrf vrf-r2

	ip address del fe80:3::23/64 dev $rp23
	ip address del 169.254.3.23/24 dev $rp23

	ip address del fe80:2::22/64 dev $rp22
	ip address del 169.254.2.22/24 dev $rp22

	ip address del 2001:db8:2::1/64 dev $rp21
	ip address del 198.51.100.1/24 dev $rp21

	ip nexthop del id 201
	ip nexthop del id 202
	ip nexthop del id 204
	ip nexthop del id 205

	ip link set dev $rp23 down
	ip link set dev $rp22 down
	ip link set dev $rp21 down

	vrf_destroy "vrf-r2"
}

routing_nh_obj()
{
	ip nexthop add id 101 via 169.254.2.22 dev $rp12
	ip nexthop add id 102 via 169.254.3.23 dev $rp13
	ip nexthop add id 103 group 101/102 type resilient buckets 512 \
		idle_timer 0
	ip route add 198.51.100.0/24 vrf vrf-r1 nhid 103

	ip nexthop add id 104 via fe80:2::22 dev $rp12
	ip nexthop add id 105 via fe80:3::23 dev $rp13
	ip nexthop add id 106 group 104/105 type resilient buckets 512 \
		idle_timer 0
	ip route add 2001:db8:2::/64 vrf vrf-r1 nhid 106

	ip nexthop add id 201 via 169.254.2.12 dev $rp22
	ip nexthop add id 202 via 169.254.3.13 dev $rp23
	ip nexthop add id 203 group 201/202 type resilient buckets 512 \
		idle_timer 0
	ip route add 192.0.2.0/24 vrf vrf-r2 nhid 203

	ip nexthop add id 204 via fe80:2::12 dev $rp22
	ip nexthop add id 205 via fe80:3::13 dev $rp23
	ip nexthop add id 206 group 204/205 type resilient buckets 512 \
		idle_timer 0
	ip route add 2001:db8:1::/64 vrf vrf-r2 nhid 206
}

multipath4_test()
{
	local desc="$1"
	local weight_rp12=$2
	local weight_rp13=$3
	local t0_rp12 t0_rp13 t1_rp12 t1_rp13
	local packets_rp12 packets_rp13

	# Transmit multiple flows from h1 to h2 and make sure they are
	# distributed between both multipath links (rp12 and rp13)
	# according to the provided weights.
	sysctl_set net.ipv4.fib_multipath_hash_policy 1

	t0_rp12=$(link_stats_tx_packets_get $rp12)
	t0_rp13=$(link_stats_tx_packets_get $rp13)

	ip vrf exec vrf-h1 $MZ $h1 -q -p 64 -A 192.0.2.2 -B 198.51.100.2 \
		-d $MZ_DELAY -t udp "sp=1024,dp=0-32768"

	t1_rp12=$(link_stats_tx_packets_get $rp12)
	t1_rp13=$(link_stats_tx_packets_get $rp13)

	let "packets_rp12 = $t1_rp12 - $t0_rp12"
	let "packets_rp13 = $t1_rp13 - $t0_rp13"
	multipath_eval "$desc" $weight_rp12 $weight_rp13 $packets_rp12 $packets_rp13

	# Restore settings.
	sysctl_restore net.ipv4.fib_multipath_hash_policy
}

multipath6_l4_test()
{
	local desc="$1"
	local weight_rp12=$2
	local weight_rp13=$3
	local t0_rp12 t0_rp13 t1_rp12 t1_rp13
	local packets_rp12 packets_rp13

	# Transmit multiple flows from h1 to h2 and make sure they are
	# distributed between both multipath links (rp12 and rp13)
	# according to the provided weights.
	sysctl_set net.ipv6.fib_multipath_hash_policy 1

	t0_rp12=$(link_stats_tx_packets_get $rp12)
	t0_rp13=$(link_stats_tx_packets_get $rp13)

	$MZ $h1 -6 -q -p 64 -A 2001:db8:1::2 -B 2001:db8:2::2 \
		-d $MZ_DELAY -t udp "sp=1024,dp=0-32768"

	t1_rp12=$(link_stats_tx_packets_get $rp12)
	t1_rp13=$(link_stats_tx_packets_get $rp13)

	let "packets_rp12 = $t1_rp12 - $t0_rp12"
	let "packets_rp13 = $t1_rp13 - $t0_rp13"
	multipath_eval "$desc" $weight_rp12 $weight_rp13 $packets_rp12 $packets_rp13

	sysctl_restore net.ipv6.fib_multipath_hash_policy
}

multipath_test()
{
	# Without an idle timer, weight replacement should happen immediately.
	log_info "Running multipath tests without an idle timer"
	ip nexthop replace id 103 group 101/102 type resilient idle_timer 0
	ip nexthop replace id 106 group 104/105 type resilient idle_timer 0

	log_info "Running IPv4 multipath tests"
	ip nexthop replace id 103 group 101,1/102,1 type resilient
	multipath4_test "ECMP" 1 1
	ip nexthop replace id 103 group 101,2/102,1 type resilient
	multipath4_test "Weighted MP 2:1" 2 1
	ip nexthop replace id 103 group 101,11/102,45 type resilient
	multipath4_test "Weighted MP 11:45" 11 45

	ip nexthop replace id 103 group 101,1/102,1 type resilient

	log_info "Running IPv6 L4 hash multipath tests"
	ip nexthop replace id 106 group 104,1/105,1 type resilient
	multipath6_l4_test "ECMP" 1 1
	ip nexthop replace id 106 group 104,2/105,1 type resilient
	multipath6_l4_test "Weighted MP 2:1" 2 1
	ip nexthop replace id 106 group 104,11/105,45 type resilient
	multipath6_l4_test "Weighted MP 11:45" 11 45

	ip nexthop replace id 106 group 104,1/105,1 type resilient

	# With an idle timer, weight replacement should not happen, so the
	# expected ratio should always be the initial one (1:1).
	log_info "Running multipath tests with an idle timer of 120 seconds"
	ip nexthop replace id 103 group 101/102 type resilient idle_timer 120
	ip nexthop replace id 106 group 104/105 type resilient idle_timer 120

	log_info "Running IPv4 multipath tests"
	ip nexthop replace id 103 group 101,1/102,1 type resilient
	multipath4_test "ECMP" 1 1
	ip nexthop replace id 103 group 101,2/102,1 type resilient
	multipath4_test "Weighted MP 2:1" 1 1
	ip nexthop replace id 103 group 101,11/102,45 type resilient
	multipath4_test "Weighted MP 11:45" 1 1

	ip nexthop replace id 103 group 101,1/102,1 type resilient

	log_info "Running IPv6 L4 hash multipath tests"
	ip nexthop replace id 106 group 104,1/105,1 type resilient
	multipath6_l4_test "ECMP" 1 1
	ip nexthop replace id 106 group 104,2/105,1 type resilient
	multipath6_l4_test "Weighted MP 2:1" 1 1
	ip nexthop replace id 106 group 104,11/105,45 type resilient
	multipath6_l4_test "Weighted MP 11:45" 1 1

	ip nexthop replace id 106 group 104,1/105,1 type resilient

	# With a short idle timer and enough idle time, weight replacement
	# should happen.
	log_info "Running multipath tests with an idle timer of 5 seconds"
	ip nexthop replace id 103 group 101/102 type resilient idle_timer 5
	ip nexthop replace id 106 group 104/105 type resilient idle_timer 5

	log_info "Running IPv4 multipath tests"
	sleep 10
	ip nexthop replace id 103 group 101,1/102,1 type resilient
	multipath4_test "ECMP" 1 1
	sleep 10
	ip nexthop replace id 103 group 101,2/102,1 type resilient
	multipath4_test "Weighted MP 2:1" 2 1
	sleep 10
	ip nexthop replace id 103 group 101,11/102,45 type resilient
	multipath4_test "Weighted MP 11:45" 11 45

	ip nexthop replace id 103 group 101,1/102,1 type resilient

	log_info "Running IPv6 L4 hash multipath tests"
	sleep 10
	ip nexthop replace id 106 group 104,1/105,1 type resilient
	multipath6_l4_test "ECMP" 1 1
	sleep 10
	ip nexthop replace id 106 group 104,2/105,1 type resilient
	multipath6_l4_test "Weighted MP 2:1" 2 1
	sleep 10
	ip nexthop replace id 106 group 104,11/105,45 type resilient
	multipath6_l4_test "Weighted MP 11:45" 11 45

	ip nexthop replace id 106 group 104,1/105,1 type resilient
}

nh_stats_test_v4()
{
	__nh_stats_test_v4 resilient
}

nh_stats_test_v6()
{
	__nh_stats_test_v6 resilient
}

setup_prepare()
{
	h1=${NETIFS[p1]}
	rp11=${NETIFS[p2]}

	rp12=${NETIFS[p3]}
	rp22=${NETIFS[p4]}

	rp13=${NETIFS[p5]}
	rp23=${NETIFS[p6]}

	rp21=${NETIFS[p7]}
	h2=${NETIFS[p8]}

	vrf_prepare

	h1_create
	h2_create

	router1_create
	router2_create

	forwarding_enable
}

cleanup()
{
	pre_cleanup

	forwarding_restore

	router2_destroy
	router1_destroy

	h2_destroy
	h1_destroy

	vrf_cleanup
}

ping_ipv4()
{
	ping_test $h1 198.51.100.2
}

ping_ipv6()
{
	ping6_test $h1 2001:db8:2::2
}

ip nexthop ls >/dev/null 2>&1
if [ $? -ne 0 ]; then
	echo "Nexthop objects not supported; skipping tests"
	exit $ksft_skip
fi

trap cleanup EXIT

setup_prepare
setup_wait
routing_nh_obj

tests_run

exit $EXIT_STATUS