#!/bin/sh
# SPDX-License-Identifier: GPL-2.0
#
# Check that route PMTU values match expectations, and that initial device MTU
# values are assigned correctly
#
# Tests currently implemented:
#
# - pmtu_ipv4
# Set up two namespaces, A and B, with two paths between them over routers
# R1 and R2 (also implemented with namespaces), with different MTUs:
#
# segment a_r1 segment b_r1 a_r1: 2000
# .--------------R1--------------. a_r2: 1500
# A B a_r3: 2000
# '--------------R2--------------' a_r4: 1400
# segment a_r2 segment b_r2
#
# Check that PMTU exceptions with the correct PMTU are created. Then
# decrease and increase the MTU of the local link for one of the paths,
# A to R1, checking that route exception PMTU changes accordingly over
# this path. Also check that locked exceptions are created when an ICMP
# message advertising a PMTU smaller than net.ipv4.route.min_pmtu is
# received
#
# - pmtu_ipv6
# Same as pmtu_ipv4, except for locked PMTU tests, using IPv6
#
# - pmtu_ipv4_vxlan4_exception
# Set up the same network topology as pmtu_ipv4, create a VXLAN tunnel
# over IPv4 between A and B, routed via R1. On the link between R1 and B,
# set a MTU lower than the VXLAN MTU and the MTU on the link between A and
# R1. Send IPv4 packets, exceeding the MTU between R1 and B, over VXLAN
# from A to B and check that the PMTU exception is created with the right
# value on A
#
# - pmtu_ipv6_vxlan4_exception
# Same as pmtu_ipv4_vxlan4_exception, but send IPv6 packets from A to B
#
# - pmtu_ipv4_vxlan6_exception
# Same as pmtu_ipv4_vxlan4_exception, but use IPv6 transport from A to B
#
# - pmtu_ipv6_vxlan6_exception
# Same as pmtu_ipv4_vxlan6_exception, but send IPv6 packets from A to B
#
# - pmtu_ipv4_geneve4_exception
# Same as pmtu_ipv4_vxlan4_exception, but using a GENEVE tunnel instead of
# VXLAN
#
# - pmtu_ipv6_geneve4_exception
# Same as pmtu_ipv6_vxlan4_exception, but using a GENEVE tunnel instead of
# VXLAN
#
# - pmtu_ipv4_geneve6_exception
# Same as pmtu_ipv4_vxlan6_exception, but using a GENEVE tunnel instead of
# VXLAN
#
# - pmtu_ipv6_geneve6_exception
# Same as pmtu_ipv6_vxlan6_exception, but using a GENEVE tunnel instead of
# VXLAN
#
# - pmtu_ipv{4,6}_fou{4,6}_exception
# Same as pmtu_ipv4_vxlan4, but using a direct IPv4/IPv6 encapsulation
# (FoU) over IPv4/IPv6, instead of VXLAN
#
# - pmtu_ipv{4,6}_fou{4,6}_exception
# Same as pmtu_ipv4_vxlan4, but using a generic UDP IPv4/IPv6
# encapsulation (GUE) over IPv4/IPv6, instead of VXLAN
#
# - pmtu_vti4_exception
# Set up vti tunnel on top of veth, with xfrm states and policies, in two
# namespaces with matching endpoints. Check that route exception is not
# created if link layer MTU is not exceeded, then exceed it and check that
# exception is created with the expected PMTU. The approach described
# below for IPv6 doesn't apply here, because, on IPv4, administrative MTU
# changes alone won't affect PMTU
#
# - pmtu_vti6_exception
# Set up vti6 tunnel on top of veth, with xfrm states and policies, in two
# namespaces with matching endpoints. Check that route exception is
# created by exceeding link layer MTU with ping to other endpoint. Then
# decrease and increase MTU of tunnel, checking that route exception PMTU
# changes accordingly
#
# - pmtu_vti4_default_mtu
# Set up vti4 tunnel on top of veth, in two namespaces with matching
# endpoints. Check that MTU assigned to vti interface is the MTU of the
# lower layer (veth) minus additional lower layer headers (zero, for veth)
# minus IPv4 header length
#
# - pmtu_vti6_default_mtu
# Same as above, for IPv6
#
# - pmtu_vti4_link_add_mtu
# Set up vti4 interface passing MTU value at link creation, check MTU is
# configured, and that link is not created with invalid MTU values
#
# - pmtu_vti6_link_add_mtu
# Same as above, for IPv6
#
# - pmtu_vti6_link_change_mtu
# Set up two dummy interfaces with different MTUs, create a vti6 tunnel
# and check that configured MTU is used on link creation and changes, and
# that MTU is properly calculated instead when MTU is not configured from
# userspace
# Kselftest framework requirement - SKIP code is 4.
ksft_skip=4
# Some systems don't have a ping6 binary anymore
which ping6 > /dev/null 2>&1 && ping6=$(which ping6) || ping6=$(which ping)
tests="
pmtu_ipv4_exception ipv4: PMTU exceptions
pmtu_ipv6_exception ipv6: PMTU exceptions
pmtu_ipv4_vxlan4_exception IPv4 over vxlan4: PMTU exceptions
pmtu_ipv6_vxlan4_exception IPv6 over vxlan4: PMTU exceptions
pmtu_ipv4_vxlan6_exception IPv4 over vxlan6: PMTU exceptions
pmtu_ipv6_vxlan6_exception IPv6 over vxlan6: PMTU exceptions
pmtu_ipv4_geneve4_exception IPv4 over geneve4: PMTU exceptions
pmtu_ipv6_geneve4_exception IPv6 over geneve4: PMTU exceptions
pmtu_ipv4_geneve6_exception IPv4 over geneve6: PMTU exceptions
pmtu_ipv6_geneve6_exception IPv6 over geneve6: PMTU exceptions
pmtu_ipv4_fou4_exception IPv4 over fou4: PMTU exceptions
pmtu_ipv6_fou4_exception IPv6 over fou4: PMTU exceptions
pmtu_ipv4_fou6_exception IPv4 over fou6: PMTU exceptions
pmtu_ipv6_fou6_exception IPv6 over fou6: PMTU exceptions
pmtu_ipv4_gue4_exception IPv4 over gue4: PMTU exceptions
pmtu_ipv6_gue4_exception IPv6 over gue4: PMTU exceptions
pmtu_ipv4_gue6_exception IPv4 over gue6: PMTU exceptions
pmtu_ipv6_gue6_exception IPv6 over gue6: PMTU exceptions
pmtu_vti6_exception vti6: PMTU exceptions
pmtu_vti4_exception vti4: PMTU exceptions
pmtu_vti4_default_mtu vti4: default MTU assignment
pmtu_vti6_default_mtu vti6: default MTU assignment
pmtu_vti4_link_add_mtu vti4: MTU setting on link creation
pmtu_vti6_link_add_mtu vti6: MTU setting on link creation
pmtu_vti6_link_change_mtu vti6: MTU changes on link changes"
NS_A="ns-$(mktemp -u XXXXXX)"
NS_B="ns-$(mktemp -u XXXXXX)"
NS_R1="ns-$(mktemp -u XXXXXX)"
NS_R2="ns-$(mktemp -u XXXXXX)"
ns_a="ip netns exec ${NS_A}"
ns_b="ip netns exec ${NS_B}"
ns_r1="ip netns exec ${NS_R1}"
ns_r2="ip netns exec ${NS_R2}"
# Addressing and routing for tests with routers: four network segments, with
# index SEGMENT between 1 and 4, a common prefix (PREFIX4 or PREFIX6) and an
# identifier ID, which is 1 for hosts (A and B), 2 for routers (R1 and R2).
# Addresses are:
# - IPv4: PREFIX4.SEGMENT.ID (/24)
# - IPv6: PREFIX6:SEGMENT::ID (/64)
prefix4="10.0"
prefix6="fc00"
a_r1=1
a_r2=2
b_r1=3
b_r2=4
# ns peer segment
routing_addrs="
A R1 ${a_r1}
A R2 ${a_r2}
B R1 ${b_r1}
B R2 ${b_r2}
"
# Traffic from A to B goes through R1 by default, and through R2, if destined to
# B's address on the b_r2 segment.
# Traffic from B to A goes through R1.
# ns destination gateway
routes="
A default ${prefix4}.${a_r1}.2
A ${prefix4}.${b_r2}.1 ${prefix4}.${a_r2}.2
B default ${prefix4}.${b_r1}.2
A default ${prefix6}:${a_r1}::2
A ${prefix6}:${b_r2}::1 ${prefix6}:${a_r2}::2
B default ${prefix6}:${b_r1}::2
"
veth4_a_addr="192.168.1.1"
veth4_b_addr="192.168.1.2"
veth4_mask="24"
veth6_a_addr="fd00:1::a"
veth6_b_addr="fd00:1::b"
veth6_mask="64"
tunnel4_a_addr="192.168.2.1"
tunnel4_b_addr="192.168.2.2"
tunnel4_mask="24"
tunnel6_a_addr="fd00:2::a"
tunnel6_b_addr="fd00:2::b"
tunnel6_mask="64"
dummy6_0_addr="fc00:1000::0"
dummy6_1_addr="fc00:1001::0"
dummy6_mask="64"
cleanup_done=1
err_buf=
tcpdump_pids=
err() {
err_buf="${err_buf}${1}
"
}
err_flush() {
echo -n "${err_buf}"
err_buf=
}
# Find the auto-generated name for this namespace
nsname() {
eval echo \$NS_$1
}
setup_fou_or_gue() {
outer="${1}"
inner="${2}"
encap="${3}"
if [ "${outer}" = "4" ]; then
modprobe fou || return 2
a_addr="${prefix4}.${a_r1}.1"
b_addr="${prefix4}.${b_r1}.1"
if [ "${inner}" = "4" ]; then
type="ipip"
ipproto="4"
else
type="sit"
ipproto="41"
fi
else
modprobe fou6 || return 2
a_addr="${prefix6}:${a_r1}::1"
b_addr="${prefix6}:${b_r1}::1"
if [ "${inner}" = "4" ]; then
type="ip6tnl"
mode="mode ipip6"
ipproto="4 -6"
else
type="ip6tnl"
mode="mode ip6ip6"
ipproto="41 -6"
fi
fi
${ns_a} ip fou add port 5555 ipproto ${ipproto} || return 2
${ns_a} ip link add ${encap}_a type ${type} ${mode} local ${a_addr} remote ${b_addr} encap ${encap} encap-sport auto encap-dport 5556 || return 2
${ns_b} ip fou add port 5556 ipproto ${ipproto}
${ns_b} ip link add ${encap}_b type ${type} ${mode} local ${b_addr} remote ${a_addr} encap ${encap} encap-sport auto encap-dport 5555
if [ "${inner}" = "4" ]; then
${ns_a} ip addr add ${tunnel4_a_addr}/${tunnel4_mask} dev ${encap}_a
${ns_b} ip addr add ${tunnel4_b_addr}/${tunnel4_mask} dev ${encap}_b
else
${ns_a} ip addr add ${tunnel6_a_addr}/${tunnel6_mask} dev ${encap}_a
${ns_b} ip addr add ${tunnel6_b_addr}/${tunnel6_mask} dev ${encap}_b
fi
${ns_a} ip link set ${encap}_a up
${ns_b} ip link set ${encap}_b up
sleep 1
}
setup_fou44() {
setup_fou_or_gue 4 4 fou
}
setup_fou46() {
setup_fou_or_gue 4 6 fou
}
setup_fou64() {
setup_fou_or_gue 6 4 fou
}
setup_fou66() {
setup_fou_or_gue 6 6 fou
}
setup_gue44() {
setup_fou_or_gue 4 4 gue
}
setup_gue46() {
setup_fou_or_gue 4 6 gue
}
setup_gue64() {
setup_fou_or_gue 6 4 gue
}
setup_gue66() {
setup_fou_or_gue 6 6 gue
}
setup_namespaces() {
for n in ${NS_A} ${NS_B} ${NS_R1} ${NS_R2}; do
ip netns add ${n} || return 1
done
}
setup_veth() {
${ns_a} ip link add veth_a type veth peer name veth_b || return 1
${ns_a} ip link set veth_b netns ${NS_B}
${ns_a} ip addr add ${veth4_a_addr}/${veth4_mask} dev veth_a
${ns_b} ip addr add ${veth4_b_addr}/${veth4_mask} dev veth_b
${ns_a} ip addr add ${veth6_a_addr}/${veth6_mask} dev veth_a
${ns_b} ip addr add ${veth6_b_addr}/${veth6_mask} dev veth_b
${ns_a} ip link set veth_a up
${ns_b} ip link set veth_b up
}
setup_vti() {
proto=${1}
veth_a_addr="${2}"
veth_b_addr="${3}"
vti_a_addr="${4}"
vti_b_addr="${5}"
vti_mask=${6}
[ ${proto} -eq 6 ] && vti_type="vti6" || vti_type="vti"
${ns_a} ip link add vti${proto}_a type ${vti_type} local ${veth_a_addr} remote ${veth_b_addr} key 10 || return 1
${ns_b} ip link add vti${proto}_b type ${vti_type} local ${veth_b_addr} remote ${veth_a_addr} key 10
${ns_a} ip addr add ${vti_a_addr}/${vti_mask} dev vti${proto}_a
${ns_b} ip addr add ${vti_b_addr}/${vti_mask} dev vti${proto}_b
${ns_a} ip link set vti${proto}_a up
${ns_b} ip link set vti${proto}_b up
sleep 1
}
setup_vti4() {
setup_vti 4 ${veth4_a_addr} ${veth4_b_addr} ${tunnel4_a_addr} ${tunnel4_b_addr} ${tunnel4_mask}
}
setup_vti6() {
setup_vti 6 ${veth6_a_addr} ${veth6_b_addr} ${tunnel6_a_addr} ${tunnel6_b_addr} ${tunnel6_mask}
}
setup_vxlan_or_geneve() {
type="${1}"
a_addr="${2}"
b_addr="${3}"
opts="${4}"
if [ "${type}" = "vxlan" ]; then
opts="${opts} ttl 64 dstport 4789"
opts_a="local ${a_addr}"
opts_b="local ${b_addr}"
else
opts_a=""
opts_b=""
fi
${ns_a} ip link add ${type}_a type ${type} id 1 ${opts_a} remote ${b_addr} ${opts} || return 1
${ns_b} ip link add ${type}_b type ${type} id 1 ${opts_b} remote ${a_addr} ${opts}
${ns_a} ip addr add ${tunnel4_a_addr}/${tunnel4_mask} dev ${type}_a
${ns_b} ip addr add ${tunnel4_b_addr}/${tunnel4_mask} dev ${type}_b
${ns_a} ip addr add ${tunnel6_a_addr}/${tunnel6_mask} dev ${type}_a
${ns_b} ip addr add ${tunnel6_b_addr}/${tunnel6_mask} dev ${type}_b
${ns_a} ip link set ${type}_a up
${ns_b} ip link set ${type}_b up
sleep 1
}
setup_geneve4() {
setup_vxlan_or_geneve geneve ${prefix4}.${a_r1}.1 ${prefix4}.${b_r1}.1 "df set"
}
setup_vxlan4() {
setup_vxlan_or_geneve vxlan ${prefix4}.${a_r1}.1 ${prefix4}.${b_r1}.1 "df set"
}
setup_geneve6() {
setup_vxlan_or_geneve geneve ${prefix6}:${a_r1}::1 ${prefix6}:${b_r1}::1
}
setup_vxlan6() {
setup_vxlan_or_geneve vxlan ${prefix6}:${a_r1}::1 ${prefix6}:${b_r1}::1
}
setup_xfrm() {
proto=${1}
veth_a_addr="${2}"
veth_b_addr="${3}"
${ns_a} ip -${proto} xfrm state add src ${veth_a_addr} dst ${veth_b_addr} spi 0x1000 proto esp aead "rfc4106(gcm(aes))" 0x0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f 128 mode tunnel || return 1
${ns_a} ip -${proto} xfrm state add src ${veth_b_addr} dst ${veth_a_addr} spi 0x1001 proto esp aead "rfc4106(gcm(aes))" 0x0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f 128 mode tunnel
${ns_a} ip -${proto} xfrm policy add dir out mark 10 tmpl src ${veth_a_addr} dst ${veth_b_addr} proto esp mode tunnel
${ns_a} ip -${proto} xfrm policy add dir in mark 10 tmpl src ${veth_b_addr} dst ${veth_a_addr} proto esp mode tunnel
${ns_b} ip -${proto} xfrm state add src ${veth_a_addr} dst ${veth_b_addr} spi 0x1000 proto esp aead "rfc4106(gcm(aes))" 0x0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f 128 mode tunnel
${ns_b} ip -${proto} xfrm state add src ${veth_b_addr} dst ${veth_a_addr} spi 0x1001 proto esp aead "rfc4106(gcm(aes))" 0x0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f 128 mode tunnel
${ns_b} ip -${proto} xfrm policy add dir out mark 10 tmpl src ${veth_b_addr} dst ${veth_a_addr} proto esp mode tunnel
${ns_b} ip -${proto} xfrm policy add dir in mark 10 tmpl src ${veth_a_addr} dst ${veth_b_addr} proto esp mode tunnel
}
setup_xfrm4() {
setup_xfrm 4 ${veth4_a_addr} ${veth4_b_addr}
}
setup_xfrm6() {
setup_xfrm 6 ${veth6_a_addr} ${veth6_b_addr}
}
setup_routing() {
for i in ${NS_R1} ${NS_R2}; do
ip netns exec ${i} sysctl -q net/ipv4/ip_forward=1
ip netns exec ${i} sysctl -q net/ipv6/conf/all/forwarding=1
done
for i in ${routing_addrs}; do
[ "${ns}" = "" ] && ns="${i}" && continue
[ "${peer}" = "" ] && peer="${i}" && continue
[ "${segment}" = "" ] && segment="${i}"
ns_name="$(nsname ${ns})"
peer_name="$(nsname ${peer})"
if="veth_${ns}-${peer}"
ifpeer="veth_${peer}-${ns}"
# Create veth links
ip link add ${if} up netns ${ns_name} type veth peer name ${ifpeer} netns ${peer_name} || return 1
ip -n ${peer_name} link set dev ${ifpeer} up
# Add addresses
ip -n ${ns_name} addr add ${prefix4}.${segment}.1/24 dev ${if}
ip -n ${ns_name} addr add ${prefix6}:${segment}::1/64 dev ${if}
ip -n ${peer_name} addr add ${prefix4}.${segment}.2/24 dev ${ifpeer}
ip -n ${peer_name} addr add ${prefix6}:${segment}::2/64 dev ${ifpeer}
ns=""; peer=""; segment=""
done
for i in ${routes}; do
[ "${ns}" = "" ] && ns="${i}" && continue
[ "${addr}" = "" ] && addr="${i}" && continue
[ "${gw}" = "" ] && gw="${i}"
ns_name="$(nsname ${ns})"
ip -n ${ns_name} route add ${addr} via ${gw}
ns=""; addr=""; gw=""
done
}
setup() {
[ "$(id -u)" -ne 0 ] && echo " need to run as root" && return $ksft_skip
cleanup_done=0
for arg do
eval setup_${arg} || { echo " ${arg} not supported"; return 1; }
done
}
trace() {
[ $tracing -eq 0 ] && return
for arg do
[ "${ns_cmd}" = "" ] && ns_cmd="${arg}" && continue
${ns_cmd} tcpdump -s 0 -i "${arg}" -w "${name}_${arg}.pcap" 2> /dev/null &
tcpdump_pids="${tcpdump_pids} $!"
ns_cmd=
done
sleep 1
}
cleanup() {
for pid in ${tcpdump_pids}; do
kill ${pid}
done
tcpdump_pids=
[ ${cleanup_done} -eq 1 ] && return
for n in ${NS_A} ${NS_B} ${NS_R1} ${NS_R2}; do
ip netns del ${n} 2> /dev/null
done
cleanup_done=1
}
mtu() {
ns_cmd="${1}"
dev="${2}"
mtu="${3}"
${ns_cmd} ip link set dev ${dev} mtu ${mtu}
}
mtu_parse() {
input="${1}"
next=0
for i in ${input}; do
[ ${next} -eq 1 -a "${i}" = "lock" ] && next=2 && continue
[ ${next} -eq 1 ] && echo "${i}" && return
[ ${next} -eq 2 ] && echo "lock ${i}" && return
[ "${i}" = "mtu" ] && next=1
done
}
link_get() {
ns_cmd="${1}"
name="${2}"
${ns_cmd} ip link show dev "${name}"
}
link_get_mtu() {
ns_cmd="${1}"
name="${2}"
mtu_parse "$(link_get "${ns_cmd}" ${name})"
}
route_get_dst_exception() {
ns_cmd="${1}"
dst="${2}"
${ns_cmd} ip route get "${dst}"
}
route_get_dst_pmtu_from_exception() {
ns_cmd="${1}"
dst="${2}"
mtu_parse "$(route_get_dst_exception "${ns_cmd}" ${dst})"
}
check_pmtu_value() {
expected="${1}"
value="${2}"
event="${3}"
[ "${expected}" = "any" ] && [ -n "${value}" ] && return 0
[ "${value}" = "${expected}" ] && return 0
[ -z "${value}" ] && err " PMTU exception wasn't created after ${event}" && return 1
[ -z "${expected}" ] && err " PMTU exception shouldn't exist after ${event}" && return 1
err " found PMTU exception with incorrect MTU ${value}, expected ${expected}, after ${event}"
return 1
}
test_pmtu_ipvX() {
family=${1}
setup namespaces routing || return 2
trace "${ns_a}" veth_A-R1 "${ns_r1}" veth_R1-A \
"${ns_r1}" veth_R1-B "${ns_b}" veth_B-R1 \
"${ns_a}" veth_A-R2 "${ns_r2}" veth_R2-A \
"${ns_r2}" veth_R2-B "${ns_b}" veth_B-R2
if [ ${family} -eq 4 ]; then
ping=ping
dst1="${prefix4}.${b_r1}.1"
dst2="${prefix4}.${b_r2}.1"
else
ping=${ping6}
dst1="${prefix6}:${b_r1}::1"
dst2="${prefix6}:${b_r2}::1"
fi
# Set up initial MTU values
mtu "${ns_a}" veth_A-R1 2000
mtu "${ns_r1}" veth_R1-A 2000
mtu "${ns_r1}" veth_R1-B 1400
mtu "${ns_b}" veth_B-R1 1400
mtu "${ns_a}" veth_A-R2 2000
mtu "${ns_r2}" veth_R2-A 2000
mtu "${ns_r2}" veth_R2-B 1500
mtu "${ns_b}" veth_B-R2 1500
# Create route exceptions
${ns_a} ${ping} -q -M want -i 0.1 -w 2 -s 1800 ${dst1} > /dev/null
${ns_a} ${ping} -q -M want -i 0.1 -w 2 -s 1800 ${dst2} > /dev/null
# Check that exceptions have been created with the correct PMTU
pmtu_1="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst1})"
check_pmtu_value "1400" "${pmtu_1}" "exceeding MTU" || return 1
pmtu_2="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst2})"
check_pmtu_value "1500" "${pmtu_2}" "exceeding MTU" || return 1
# Decrease local MTU below PMTU, check for PMTU decrease in route exception
mtu "${ns_a}" veth_A-R1 1300
mtu "${ns_r1}" veth_R1-A 1300
pmtu_1="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst1})"
check_pmtu_value "1300" "${pmtu_1}" "decreasing local MTU" || return 1
# Second exception shouldn't be modified
pmtu_2="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst2})"
check_pmtu_value "1500" "${pmtu_2}" "changing local MTU on a link not on this path" || return 1
# Increase MTU, check for PMTU increase in route exception
mtu "${ns_a}" veth_A-R1 1700
mtu "${ns_r1}" veth_R1-A 1700
pmtu_1="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst1})"
check_pmtu_value "1700" "${pmtu_1}" "increasing local MTU" || return 1
# Second exception shouldn't be modified
pmtu_2="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst2})"
check_pmtu_value "1500" "${pmtu_2}" "changing local MTU on a link not on this path" || return 1
# Skip PMTU locking tests for IPv6
[ $family -eq 6 ] && return 0
# Decrease remote MTU on path via R2, get new exception
mtu "${ns_r2}" veth_R2-B 400
mtu "${ns_b}" veth_B-R2 400
${ns_a} ${ping} -q -M want -i 0.1 -w 2 -s 1400 ${dst2} > /dev/null
pmtu_2="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst2})"
check_pmtu_value "lock 552" "${pmtu_2}" "exceeding MTU, with MTU < min_pmtu" || return 1
# Decrease local MTU below PMTU
mtu "${ns_a}" veth_A-R2 500
mtu "${ns_r2}" veth_R2-A 500
pmtu_2="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst2})"
check_pmtu_value "500" "${pmtu_2}" "decreasing local MTU" || return 1
# Increase local MTU
mtu "${ns_a}" veth_A-R2 1500
mtu "${ns_r2}" veth_R2-A 1500
pmtu_2="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst2})"
check_pmtu_value "1500" "${pmtu_2}" "increasing local MTU" || return 1
# Get new exception
${ns_a} ${ping} -q -M want -i 0.1 -w 2 -s 1400 ${dst2} > /dev/null
pmtu_2="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst2})"
check_pmtu_value "lock 552" "${pmtu_2}" "exceeding MTU, with MTU < min_pmtu" || return 1
}
test_pmtu_ipv4_exception() {
test_pmtu_ipvX 4
}
test_pmtu_ipv6_exception() {
test_pmtu_ipvX 6
}
test_pmtu_ipvX_over_vxlanY_or_geneveY_exception() {
type=${1}
family=${2}
outer_family=${3}
ll_mtu=4000
if [ ${outer_family} -eq 4 ]; then
setup namespaces routing ${type}4 || return 2
# IPv4 header UDP header VXLAN/GENEVE header Ethernet header
exp_mtu=$((${ll_mtu} - 20 - 8 - 8 - 14))
else
setup namespaces routing ${type}6 || return 2
# IPv6 header UDP header VXLAN/GENEVE header Ethernet header
exp_mtu=$((${ll_mtu} - 40 - 8 - 8 - 14))
fi
trace "${ns_a}" ${type}_a "${ns_b}" ${type}_b \
"${ns_a}" veth_A-R1 "${ns_r1}" veth_R1-A \
"${ns_b}" veth_B-R1 "${ns_r1}" veth_R1-B
if [ ${family} -eq 4 ]; then
ping=ping
dst=${tunnel4_b_addr}
else
ping=${ping6}
dst=${tunnel6_b_addr}
fi
# Create route exception by exceeding link layer MTU
mtu "${ns_a}" veth_A-R1 $((${ll_mtu} + 1000))
mtu "${ns_r1}" veth_R1-A $((${ll_mtu} + 1000))
mtu "${ns_b}" veth_B-R1 ${ll_mtu}
mtu "${ns_r1}" veth_R1-B ${ll_mtu}
mtu "${ns_a}" ${type}_a $((${ll_mtu} + 1000))
mtu "${ns_b}" ${type}_b $((${ll_mtu} + 1000))
${ns_a} ${ping} -q -M want -i 0.1 -w 2 -s $((${ll_mtu} + 500)) ${dst} > /dev/null
# Check that exception was created
pmtu="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst})"
check_pmtu_value ${exp_mtu} "${pmtu}" "exceeding link layer MTU on ${type} interface"
}
test_pmtu_ipv4_vxlan4_exception() {
test_pmtu_ipvX_over_vxlanY_or_geneveY_exception vxlan 4 4
}
test_pmtu_ipv6_vxlan4_exception() {
test_pmtu_ipvX_over_vxlanY_or_geneveY_exception vxlan 6 4
}
test_pmtu_ipv4_geneve4_exception() {
test_pmtu_ipvX_over_vxlanY_or_geneveY_exception geneve 4 4
}
test_pmtu_ipv6_geneve4_exception() {
test_pmtu_ipvX_over_vxlanY_or_geneveY_exception geneve 6 4
}
test_pmtu_ipv4_vxlan6_exception() {
test_pmtu_ipvX_over_vxlanY_or_geneveY_exception vxlan 4 6
}
test_pmtu_ipv6_vxlan6_exception() {
test_pmtu_ipvX_over_vxlanY_or_geneveY_exception vxlan 6 6
}
test_pmtu_ipv4_geneve6_exception() {
test_pmtu_ipvX_over_vxlanY_or_geneveY_exception geneve 4 6
}
test_pmtu_ipv6_geneve6_exception() {
test_pmtu_ipvX_over_vxlanY_or_geneveY_exception geneve 6 6
}
test_pmtu_ipvX_over_fouY_or_gueY() {
inner_family=${1}
outer_family=${2}
encap=${3}
ll_mtu=4000
setup namespaces routing ${encap}${outer_family}${inner_family} || return 2
trace "${ns_a}" ${encap}_a "${ns_b}" ${encap}_b \
"${ns_a}" veth_A-R1 "${ns_r1}" veth_R1-A \
"${ns_b}" veth_B-R1 "${ns_r1}" veth_R1-B
if [ ${inner_family} -eq 4 ]; then
ping=ping
dst=${tunnel4_b_addr}
else
ping=${ping6}
dst=${tunnel6_b_addr}
fi
if [ "${encap}" = "gue" ]; then
encap_overhead=4
else
encap_overhead=0
fi
if [ ${outer_family} -eq 4 ]; then
# IPv4 header UDP header
exp_mtu=$((${ll_mtu} - 20 - 8 - ${encap_overhead}))
else
# IPv6 header Option 4 UDP header
exp_mtu=$((${ll_mtu} - 40 - 8 - 8 - ${encap_overhead}))
fi
# Create route exception by exceeding link layer MTU
mtu "${ns_a}" veth_A-R1 $((${ll_mtu} + 1000))
mtu "${ns_r1}" veth_R1-A $((${ll_mtu} + 1000))
mtu "${ns_b}" veth_B-R1 ${ll_mtu}
mtu "${ns_r1}" veth_R1-B ${ll_mtu}
mtu "${ns_a}" ${encap}_a $((${ll_mtu} + 1000))
mtu "${ns_b}" ${encap}_b $((${ll_mtu} + 1000))
${ns_a} ${ping} -q -M want -i 0.1 -w 2 -s $((${ll_mtu} + 500)) ${dst} > /dev/null
# Check that exception was created
pmtu="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst})"
check_pmtu_value ${exp_mtu} "${pmtu}" "exceeding link layer MTU on ${encap} interface"
}
test_pmtu_ipv4_fou4_exception() {
test_pmtu_ipvX_over_fouY_or_gueY 4 4 fou
}
test_pmtu_ipv6_fou4_exception() {
test_pmtu_ipvX_over_fouY_or_gueY 6 4 fou
}
test_pmtu_ipv4_fou6_exception() {
test_pmtu_ipvX_over_fouY_or_gueY 4 6 fou
}
test_pmtu_ipv6_fou6_exception() {
test_pmtu_ipvX_over_fouY_or_gueY 6 6 fou
}
test_pmtu_ipv4_gue4_exception() {
test_pmtu_ipvX_over_fouY_or_gueY 4 4 gue
}
test_pmtu_ipv6_gue4_exception() {
test_pmtu_ipvX_over_fouY_or_gueY 6 4 gue
}
test_pmtu_ipv4_gue6_exception() {
test_pmtu_ipvX_over_fouY_or_gueY 4 6 gue
}
test_pmtu_ipv6_gue6_exception() {
test_pmtu_ipvX_over_fouY_or_gueY 6 6 gue
}
test_pmtu_vti4_exception() {
setup namespaces veth vti4 xfrm4 || return 2
trace "${ns_a}" veth_a "${ns_b}" veth_b \
"${ns_a}" vti4_a "${ns_b}" vti4_b
veth_mtu=1500
vti_mtu=$((veth_mtu - 20))
# SPI SN IV ICV pad length next header
esp_payload_rfc4106=$((vti_mtu - 4 - 4 - 8 - 16 - 1 - 1))
ping_payload=$((esp_payload_rfc4106 - 28))
mtu "${ns_a}" veth_a ${veth_mtu}
mtu "${ns_b}" veth_b ${veth_mtu}
mtu "${ns_a}" vti4_a ${vti_mtu}
mtu "${ns_b}" vti4_b ${vti_mtu}
# Send DF packet without exceeding link layer MTU, check that no
# exception is created
${ns_a} ping -q -M want -i 0.1 -w 2 -s ${ping_payload} ${tunnel4_b_addr} > /dev/null
pmtu="$(route_get_dst_pmtu_from_exception "${ns_a}" ${tunnel4_b_addr})"
check_pmtu_value "" "${pmtu}" "sending packet smaller than PMTU (IP payload length ${esp_payload_rfc4106})" || return 1
# Now exceed link layer MTU by one byte, check that exception is created
# with the right PMTU value
${ns_a} ping -q -M want -i 0.1 -w 2 -s $((ping_payload + 1)) ${tunnel4_b_addr} > /dev/null
pmtu="$(route_get_dst_pmtu_from_exception "${ns_a}" ${tunnel4_b_addr})"
check_pmtu_value "${esp_payload_rfc4106}" "${pmtu}" "exceeding PMTU (IP payload length $((esp_payload_rfc4106 + 1)))"
}
test_pmtu_vti6_exception() {
setup namespaces veth vti6 xfrm6 || return 2
trace "${ns_a}" veth_a "${ns_b}" veth_b \
"${ns_a}" vti6_a "${ns_b}" vti6_b
fail=0
# Create route exception by exceeding link layer MTU
mtu "${ns_a}" veth_a 4000
mtu "${ns_b}" veth_b 4000
mtu "${ns_a}" vti6_a 5000
mtu "${ns_b}" vti6_b 5000
${ns_a} ${ping6} -q -i 0.1 -w 2 -s 60000 ${tunnel6_b_addr} > /dev/null
# Check that exception was created
pmtu="$(route_get_dst_pmtu_from_exception "${ns_a}" ${tunnel6_b_addr})"
check_pmtu_value any "${pmtu}" "creating tunnel exceeding link layer MTU" || return 1
# Decrease tunnel MTU, check for PMTU decrease in route exception
mtu "${ns_a}" vti6_a 3000
pmtu="$(route_get_dst_pmtu_from_exception "${ns_a}" ${tunnel6_b_addr})"
check_pmtu_value "3000" "${pmtu}" "decreasing tunnel MTU" || fail=1
# Increase tunnel MTU, check for PMTU increase in route exception
mtu "${ns_a}" vti6_a 9000
pmtu="$(route_get_dst_pmtu_from_exception "${ns_a}" ${tunnel6_b_addr})"
check_pmtu_value "9000" "${pmtu}" "increasing tunnel MTU" || fail=1
return ${fail}
}
test_pmtu_vti4_default_mtu() {
setup namespaces veth vti4 || return 2
# Check that MTU of vti device is MTU of veth minus IPv4 header length
veth_mtu="$(link_get_mtu "${ns_a}" veth_a)"
vti4_mtu="$(link_get_mtu "${ns_a}" vti4_a)"
if [ $((veth_mtu - vti4_mtu)) -ne 20 ]; then
err " vti MTU ${vti4_mtu} is not veth MTU ${veth_mtu} minus IPv4 header length"
return 1
fi
}
test_pmtu_vti6_default_mtu() {
setup namespaces veth vti6 || return 2
# Check that MTU of vti device is MTU of veth minus IPv6 header length
veth_mtu="$(link_get_mtu "${ns_a}" veth_a)"
vti6_mtu="$(link_get_mtu "${ns_a}" vti6_a)"
if [ $((veth_mtu - vti6_mtu)) -ne 40 ]; then
err " vti MTU ${vti6_mtu} is not veth MTU ${veth_mtu} minus IPv6 header length"
return 1
fi
}
test_pmtu_vti4_link_add_mtu() {
setup namespaces || return 2
${ns_a} ip link add vti4_a type vti local ${veth4_a_addr} remote ${veth4_b_addr} key 10
[ $? -ne 0 ] && err " vti not supported" && return 2
${ns_a} ip link del vti4_a
fail=0
min=68
max=$((65535 - 20))
# Check invalid values first
for v in $((min - 1)) $((max + 1)); do
${ns_a} ip link add vti4_a mtu ${v} type vti local ${veth4_a_addr} remote ${veth4_b_addr} key 10 2>/dev/null
# This can fail, or MTU can be adjusted to a proper value
[ $? -ne 0 ] && continue
mtu="$(link_get_mtu "${ns_a}" vti4_a)"
if [ ${mtu} -lt ${min} -o ${mtu} -gt ${max} ]; then
err " vti tunnel created with invalid MTU ${mtu}"
fail=1
fi
${ns_a} ip link del vti4_a
done
# Now check valid values
for v in ${min} 1300 ${max}; do
${ns_a} ip link add vti4_a mtu ${v} type vti local ${veth4_a_addr} remote ${veth4_b_addr} key 10
mtu="$(link_get_mtu "${ns_a}" vti4_a)"
${ns_a} ip link del vti4_a
if [ "${mtu}" != "${v}" ]; then
err " vti MTU ${mtu} doesn't match configured value ${v}"
fail=1
fi
done
return ${fail}
}
test_pmtu_vti6_link_add_mtu() {
setup namespaces || return 2
${ns_a} ip link add vti6_a type vti6 local ${veth6_a_addr} remote ${veth6_b_addr} key 10
[ $? -ne 0 ] && err " vti6 not supported" && return 2
${ns_a} ip link del vti6_a
fail=0
min=68 # vti6 can carry IPv4 packets too
max=$((65535 - 40))
# Check invalid values first
for v in $((min - 1)) $((max + 1)); do
${ns_a} ip link add vti6_a mtu ${v} type vti6 local ${veth6_a_addr} remote ${veth6_b_addr} key 10 2>/dev/null
# This can fail, or MTU can be adjusted to a proper value
[ $? -ne 0 ] && continue
mtu="$(link_get_mtu "${ns_a}" vti6_a)"
if [ ${mtu} -lt ${min} -o ${mtu} -gt ${max} ]; then
err " vti6 tunnel created with invalid MTU ${v}"
fail=1
fi
${ns_a} ip link del vti6_a
done
# Now check valid values
for v in 68 1280 1300 $((65535 - 40)); do
${ns_a} ip link add vti6_a mtu ${v} type vti6 local ${veth6_a_addr} remote ${veth6_b_addr} key 10
mtu="$(link_get_mtu "${ns_a}" vti6_a)"
${ns_a} ip link del vti6_a
if [ "${mtu}" != "${v}" ]; then
err " vti6 MTU ${mtu} doesn't match configured value ${v}"
fail=1
fi
done
return ${fail}
}
test_pmtu_vti6_link_change_mtu() {
setup namespaces || return 2
${ns_a} ip link add dummy0 mtu 1500 type dummy
[ $? -ne 0 ] && err " dummy not supported" && return 2
${ns_a} ip link add dummy1 mtu 3000 type dummy
${ns_a} ip link set dummy0 up
${ns_a} ip link set dummy1 up
${ns_a} ip addr add ${dummy6_0_addr}/${dummy6_mask} dev dummy0
${ns_a} ip addr add ${dummy6_1_addr}/${dummy6_mask} dev dummy1
fail=0
# Create vti6 interface bound to device, passing MTU, check it
${ns_a} ip link add vti6_a mtu 1300 type vti6 remote ${dummy6_0_addr} local ${dummy6_0_addr}
mtu="$(link_get_mtu "${ns_a}" vti6_a)"
if [ ${mtu} -ne 1300 ]; then
err " vti6 MTU ${mtu} doesn't match configured value 1300"
fail=1
fi
# Move to another device with different MTU, without passing MTU, check
# MTU is adjusted
${ns_a} ip link set vti6_a type vti6 remote ${dummy6_1_addr} local ${dummy6_1_addr}
mtu="$(link_get_mtu "${ns_a}" vti6_a)"
if [ ${mtu} -ne $((3000 - 40)) ]; then
err " vti MTU ${mtu} is not dummy MTU 3000 minus IPv6 header length"
fail=1
fi
# Move it back, passing MTU, check MTU is not overridden
${ns_a} ip link set vti6_a mtu 1280 type vti6 remote ${dummy6_0_addr} local ${dummy6_0_addr}
mtu="$(link_get_mtu "${ns_a}" vti6_a)"
if [ ${mtu} -ne 1280 ]; then
err " vti6 MTU ${mtu} doesn't match configured value 1280"
fail=1
fi
return ${fail}
}
usage() {
echo
echo "$0 [OPTIONS] [TEST]..."
echo "If no TEST argument is given, all tests will be run."
echo
echo "Options"
echo " --trace: capture traffic to TEST_INTERFACE.pcap"
echo
echo "Available tests${tests}"
exit 1
}
exitcode=0
desc=0
IFS="
"
tracing=0
for arg do
if [ "${arg}" != "${arg#--*}" ]; then
opt="${arg#--}"
if [ "${opt}" = "trace" ]; then
if which tcpdump > /dev/null 2>&1; then
tracing=1
else
echo "=== tcpdump not available, tracing disabled"
fi
else
usage
fi
else
# Check first that all requested tests are available before
# running any
command -v > /dev/null "test_${arg}" || { echo "=== Test ${arg} not found"; usage; }
fi
done
trap cleanup EXIT
for t in ${tests}; do
[ $desc -eq 0 ] && name="${t}" && desc=1 && continue || desc=0
run_this=1
for arg do
[ "${arg}" != "${arg#--*}" ] && continue
[ "${arg}" = "${name}" ] && run_this=1 && break
run_this=0
done
[ $run_this -eq 0 ] && continue
(
unset IFS
eval test_${name}
ret=$?
cleanup
if [ $ret -eq 0 ]; then
printf "TEST: %-60s [ OK ]\n" "${t}"
elif [ $ret -eq 1 ]; then
printf "TEST: %-60s [FAIL]\n" "${t}"
err_flush
exit 1
elif [ $ret -eq 2 ]; then
printf "TEST: %-60s [SKIP]\n" "${t}"
err_flush
fi
)
[ $? -ne 0 ] && exitcode=1
done
exit ${exitcode}
