#!/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 # # - cleanup_ipv4_exception # Similar to pmtu_ipv4_vxlan4_exception, but explicitly generate PMTU # exceptions on multiple CPUs and check that the veth device tear-down # happens in a timely manner # # - cleanup_ipv6_exception # Same as above, but use IPv6 transport from A to B # 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 cleanup_ipv4_exception ipv4: cleanup of cached exceptions cleanup_ipv6_exception ipv6: cleanup of cached exceptions" 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 } 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 # Disable DAD, so that we don't have to wait to use the # configured IPv6 addresses ip netns exec ${n} sysctl -q net/ipv6/conf/default/accept_dad=0 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 } 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 } 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 1 -s 1800 ${dst1} > /dev/null ${ns_a} ${ping} -q -M want -i 0.1 -w 1 -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 1 -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 1 -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 1 -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 1 -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 1 -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 1 -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 1 -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 ${fail} } check_command() { cmd=${1} if ! which ${cmd} > /dev/null 2>&1; then err " missing required command: '${cmd}'" return 1 fi return 0 } test_cleanup_vxlanX_exception() { outer="${1}" encap="vxlan" ll_mtu=4000 check_command taskset || return 2 cpu_list=$(grep -m 2 processor /proc/cpuinfo | cut -d ' ' -f 2) setup namespaces routing ${encap}${outer} || 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 "${ns_r1}" veth_R1-B # Create route exception by exceeding link layer MTU mtu "${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)) # Fill exception cache for multiple CPUs (2) # we can always use inner IPv4 for that for cpu in ${cpu_list}; do taskset --cpu-list ${cpu} ${ns_a} ping -q -M want -i 0.1 -w 1 -s $((${ll_mtu} + 500)) ${tunnel4_b_addr} > /dev/null done ${ns_a} ip link del dev veth_A-R1 & iplink_pid=$! sleep 1 if [ "$(cat /proc/${iplink_pid}/cmdline 2>/dev/null | tr -d '\0')" = "iplinkdeldevveth_A-R1" ]; then err " can't delete veth device in a timely manner, PMTU dst likely leaked" return 1 fi } test_cleanup_ipv6_exception() { test_cleanup_vxlanX_exception 6 } test_cleanup_ipv4_exception() { test_cleanup_vxlanX_exception 4 } 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}