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Diffstat (limited to '')
| -rwxr-xr-x | tools/testing/selftests/net/pmtu.sh | 477 |
1 files changed, 477 insertions, 0 deletions
diff --git a/tools/testing/selftests/net/pmtu.sh b/tools/testing/selftests/net/pmtu.sh new file mode 100755 index 000000000..0ab9423d0 --- /dev/null +++ b/tools/testing/selftests/net/pmtu.sh @@ -0,0 +1,477 @@ +#!/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_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_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_a="ip netns exec ${NS_A}" +ns_b="ip netns exec ${NS_B}" + +veth4_a_addr="192.168.1.1" +veth4_b_addr="192.168.1.2" +veth4_mask="24" +veth6_a_addr="fd00:1::a" +veth6_b_addr="fd00:1::b" +veth6_mask="64" + +vti4_a_addr="192.168.2.1" +vti4_b_addr="192.168.2.2" +vti4_mask="24" +vti6_a_addr="fd00:2::a" +vti6_b_addr="fd00:2::b" +vti6_mask="64" + +dummy6_0_addr="fc00:1000::0" +dummy6_1_addr="fc00:1001::0" +dummy6_mask="64" + +cleanup_done=1 +err_buf= + +err() { + err_buf="${err_buf}${1} +" +} + +err_flush() { + echo -n "${err_buf}" + err_buf= +} + +setup_namespaces() { + ip netns add ${NS_A} || return 1 + ip netns add ${NS_B} +} + +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} ${vti4_a_addr} ${vti4_b_addr} ${vti4_mask} +} + +setup_vti6() { + setup_vti 6 ${veth6_a_addr} ${veth6_b_addr} ${vti6_a_addr} ${vti6_b_addr} ${vti6_mask} +} + +setup_xfrm() { + proto=${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} ${veth6_b_addr} +} + +setup() { + [ "$(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 +} + +cleanup() { + [ ${cleanup_done} -eq 1 ] && return + ip netns del ${NS_A} 2> /dev/null + ip netns del ${NS_B} 2> /dev/null + cleanup_done=1 +} + +mtu() { + ns_cmd="${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 + [ ${next} -eq 1 ] && echo "${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}" ${dst})" +} + +test_pmtu_vti4_exception() { + setup namespaces veth vti4 xfrm4 || return 2 + + veth_mtu=1500 + vti_mtu=$((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} ${vti4_b_addr} > /dev/null + pmtu="$(route_get_dst_pmtu_from_exception "${ns_a}" ${vti4_b_addr})" + if [ "${pmtu}" != "" ]; then + err " unexpected exception created with PMTU ${pmtu} for IP payload length ${esp_payload_rfc4106}" + return 1 + fi + + # Now exceed link layer MTU by one byte, check that exception is created + ${ns_a} ping -q -M want -i 0.1 -w 2 -s $((ping_payload + 1)) ${vti4_b_addr} > /dev/null + pmtu="$(route_get_dst_pmtu_from_exception "${ns_a}" ${vti4_b_addr})" + if [ "${pmtu}" = "" ]; then + err " exception not created for IP payload length $((esp_payload_rfc4106 + 1))" + return 1 + fi + + # ...with the right PMTU value + if [ ${pmtu} -ne ${esp_payload_rfc4106} ]; then + err " wrong PMTU ${pmtu} in exception, expected: ${esp_payload_rfc4106}" + return 1 + fi +} + +test_pmtu_vti6_exception() { + setup namespaces veth vti6 xfrm6 || return 2 + fail=0 + + # Create route exception by exceeding link layer MTU + mtu "${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 ${vti6_b_addr} > /dev/null + + # Check that exception was created + if [ "$(route_get_dst_pmtu_from_exception "${ns_a}" ${vti6_b_addr})" = "" ]; then + err " tunnel exceeding link layer MTU didn't create route exception" + return 1 + fi + + # Decrease tunnel MTU, check for PMTU decrease in route exception + mtu "${ns_a}" vti6_a 3000 + + if [ "$(route_get_dst_pmtu_from_exception "${ns_a}" ${vti6_b_addr})" -ne 3000 ]; then + err " decreasing tunnel MTU didn't decrease route exception PMTU" + fail=1 + fi + + # Increase tunnel MTU, check for PMTU increase in route exception + mtu "${ns_a}" vti6_a 9000 + if [ "$(route_get_dst_pmtu_from_exception "${ns_a}" ${vti6_b_addr})" -ne 9000 ]; then + err " increasing tunnel MTU didn't increase route exception PMTU" + fail=1 + fi + + 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} +} + +trap cleanup EXIT + +exitcode=0 +desc=0 +IFS=" +" +for t in ${tests}; do + [ $desc -eq 0 ] && name="${t}" && desc=1 && continue || desc=0 + + ( + 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} |