From b690842d12fd6687c326663d69d5732de00c00f6 Mon Sep 17 00:00:00 2001 From: Matthias May Date: Wed, 17 Aug 2022 09:36:49 +0200 Subject: [PATCH] selftests/net: test l2 tunnel TOS/TTL inheriting There are currently 3 ip tunnels that are capable of carrying L2 traffic: gretap, vxlan and geneve. They all are capable to inherit the TOS/TTL for the outer IP-header from the inner frame. Add a test that verifies that these fields are correctly inherited. These tests failed before the following commits: b09ab9c92e50 ("ip6_tunnel: allow to inherit from VLAN encapsulated IP") 3f8a8447fd0b ("ip6_gre: use actual protocol to select xmit") 41337f52b967 ("ip6_gre: set DSCP for non-IP") 7ae29fd1be43 ("ip_tunnel: allow to inherit from VLAN encapsulated IP") 7074732c8fae ("ip_tunnels: allow VXLAN/GENEVE to inherit TOS/TTL from VLAN") ca2bb69514a8 ("geneve: do not use RT_TOS for IPv6 flowlabel") b4ab94d6adaa ("geneve: fix TOS inheriting for ipv4") Signed-off-by: Matthias May Link: https://lore.kernel.org/r/20220817073649.26117-1-matthias.may@westermo.com Signed-off-by: Jakub Kicinski --- tools/testing/selftests/net/Makefile | 1 + .../selftests/net/l2_tos_ttl_inherit.sh | 390 ++++++++++++++++++ 2 files changed, 391 insertions(+) create mode 100755 tools/testing/selftests/net/l2_tos_ttl_inherit.sh diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile index c0ee2955fe54..11a288b67e2f 100644 --- a/tools/testing/selftests/net/Makefile +++ b/tools/testing/selftests/net/Makefile @@ -42,6 +42,7 @@ TEST_PROGS += arp_ndisc_evict_nocarrier.sh TEST_PROGS += ndisc_unsolicited_na_test.sh TEST_PROGS += arp_ndisc_untracked_subnets.sh TEST_PROGS += stress_reuseport_listen.sh +TEST_PROGS := l2_tos_ttl_inherit.sh TEST_PROGS_EXTENDED := in_netns.sh setup_loopback.sh setup_veth.sh TEST_PROGS_EXTENDED += toeplitz_client.sh toeplitz.sh TEST_GEN_FILES = socket nettest diff --git a/tools/testing/selftests/net/l2_tos_ttl_inherit.sh b/tools/testing/selftests/net/l2_tos_ttl_inherit.sh new file mode 100755 index 000000000000..dca1e6f777a8 --- /dev/null +++ b/tools/testing/selftests/net/l2_tos_ttl_inherit.sh @@ -0,0 +1,390 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 + +# Author: Matthias May +# +# This script evaluates ip tunnels that are capable of carrying L2 traffic +# if they inherit or set the inheritable fields. +# Namely these tunnels are: 'gretap', 'vxlan' and 'geneve'. +# Checked inheritable fields are: TOS and TTL. +# The outer tunnel protocol of 'IPv4' or 'IPv6' is verified- +# As payload frames of type 'IPv4', 'IPv6' and 'other'(ARP) are verified. +# In addition this script also checks if forcing a specific field in the +# outer header is working. + +if [ "$(id -u)" != "0" ]; then + echo "Please run as root." + exit 0 +fi +if ! which tcpdump > /dev/null 2>&1; then + echo "No tcpdump found. Required for this test." + exit 0 +fi + +expected_tos="0x00" +expected_ttl="0" +failed=false + +get_random_tos() { + # Get a random hex tos value between 0x00 and 0xfc, a multiple of 4 + echo "0x$(tr -dc '0-9a-f' < /dev/urandom | head -c 1)\ +$(tr -dc '048c' < /dev/urandom | head -c 1)" +} +get_random_ttl() { + # Get a random dec value between 0 and 255 + printf "%d" "0x$(tr -dc '0-9a-f' < /dev/urandom | head -c 2)" +} +get_field() { + # Expects to get the 'head -n 1' of a captured frame by tcpdump. + # Parses this first line and returns the specified field. + local field="$1" + local input="$2" + local found=false + input="$(echo "$input" | tr -d '(),')" + for input_field in $input; do + if $found; then + echo "$input_field" + return + fi + # The next field that we iterate over is the looked for value + if [ "$input_field" = "$field" ]; then + found=true + fi + done + echo "0" +} +setup() { + local type="$1" + local outer="$2" + local inner="$3" + local tos_ttl="$4" + local vlan="$5" + local test_tos="0x00" + local test_ttl="0" + local ns="ip netns exec testing" + + # We don't want a test-tos of 0x00, + # because this is the value that we get when no tos is set. + expected_tos="$(get_random_tos)" + while [ "$expected_tos" = "0x00" ]; do + expected_tos="$(get_random_tos)" + done + if [ "$tos_ttl" = "random" ]; then + test_tos="$expected_tos" + tos="fixed $test_tos" + elif [ "$tos_ttl" = "inherit" ]; then + test_tos="$tos_ttl" + tos="inherit $expected_tos" + fi + + # We don't want a test-ttl of 64 or 0, + # because 64 is when no ttl is set and 0 is not a valid ttl. + expected_ttl="$(get_random_ttl)" + while [ "$expected_ttl" = "64" ] || [ "$expected_ttl" = "0" ]; do + expected_ttl="$(get_random_ttl)" + done + + if [ "$tos_ttl" = "random" ]; then + test_ttl="$expected_ttl" + ttl="fixed $test_ttl" + elif [ "$tos_ttl" = "inherit" ]; then + test_ttl="$tos_ttl" + ttl="inherit $expected_ttl" + fi + printf "│%7s │%6s │%6s │%13s │%13s │%6s │" \ + "$type" "$outer" "$inner" "$tos" "$ttl" "$vlan" + + # Create 'testing' netns, veth pair and connect main ns with testing ns + ip netns add testing + ip link add type veth + ip link set veth1 netns testing + ip link set veth0 up + $ns ip link set veth1 up + ip addr flush dev veth0 + $ns ip addr flush dev veth1 + + local local_addr1="" + local local_addr2="" + if [ "$type" = "gre" ] || [ "$type" = "vxlan" ]; then + if [ "$outer" = "4" ]; then + local_addr1="local 198.18.0.1" + local_addr2="local 198.18.0.2" + elif [ "$outer" = "6" ]; then + local_addr1="local fdd1:ced0:5d88:3fce::1" + local_addr2="local fdd1:ced0:5d88:3fce::2" + fi + fi + local vxlan="" + if [ "$type" = "vxlan" ]; then + vxlan="vni 100 dstport 4789" + fi + local geneve="" + if [ "$type" = "geneve" ]; then + geneve="vni 100" + fi + # Create tunnel and assign outer IPv4/IPv6 addresses + if [ "$outer" = "4" ]; then + if [ "$type" = "gre" ]; then + type="gretap" + fi + ip addr add 198.18.0.1/24 dev veth0 + $ns ip addr add 198.18.0.2/24 dev veth1 + ip link add name tep0 type $type $local_addr1 remote \ + 198.18.0.2 tos $test_tos ttl $test_ttl $vxlan $geneve + $ns ip link add name tep1 type $type $local_addr2 remote \ + 198.18.0.1 tos $test_tos ttl $test_ttl $vxlan $geneve + elif [ "$outer" = "6" ]; then + if [ "$type" = "gre" ]; then + type="ip6gretap" + fi + ip addr add fdd1:ced0:5d88:3fce::1/64 dev veth0 + $ns ip addr add fdd1:ced0:5d88:3fce::2/64 dev veth1 + ip link add name tep0 type $type $local_addr1 \ + remote fdd1:ced0:5d88:3fce::2 tos $test_tos ttl $test_ttl \ + $vxlan $geneve + $ns ip link add name tep1 type $type $local_addr2 \ + remote fdd1:ced0:5d88:3fce::1 tos $test_tos ttl $test_ttl \ + $vxlan $geneve + fi + + # Bring L2-tunnel link up and create VLAN on top + ip link set tep0 up + $ns ip link set tep1 up + ip addr flush dev tep0 + $ns ip addr flush dev tep1 + local parent + if $vlan; then + parent="vlan99-" + ip link add link tep0 name ${parent}0 type vlan id 99 + $ns ip link add link tep1 name ${parent}1 type vlan id 99 + ip link set ${parent}0 up + $ns ip link set ${parent}1 up + ip addr flush dev ${parent}0 + $ns ip addr flush dev ${parent}1 + else + parent="tep" + fi + + # Assign inner IPv4/IPv6 addresses + if [ "$inner" = "4" ] || [ "$inner" = "other" ]; then + ip addr add 198.19.0.1/24 brd + dev ${parent}0 + $ns ip addr add 198.19.0.2/24 brd + dev ${parent}1 + elif [ "$inner" = "6" ]; then + ip addr add fdd4:96cf:4eae:443b::1/64 dev ${parent}0 + $ns ip addr add fdd4:96cf:4eae:443b::2/64 dev ${parent}1 + fi +} + +verify() { + local outer="$1" + local inner="$2" + local tos_ttl="$3" + local vlan="$4" + + local ping_pid out captured_tos captured_ttl result + + local ping_dst + if [ "$inner" = "4" ]; then + ping_dst="198.19.0.2" + elif [ "$inner" = "6" ]; then + ping_dst="fdd4:96cf:4eae:443b::2" + elif [ "$inner" = "other" ]; then + ping_dst="198.19.0.3" # Generates ARPs which are not IPv4/IPv6 + fi + if [ "$tos_ttl" = "inherit" ]; then + ping -i 0.1 $ping_dst -Q "$expected_tos" -t "$expected_ttl" \ + 2>/dev/null 1>&2 & ping_pid="$!" + else + ping -i 0.1 $ping_dst 2>/dev/null 1>&2 & ping_pid="$!" + fi + local tunnel_type_offset tunnel_type_proto req_proto_offset req_offset + if [ "$type" = "gre" ]; then + tunnel_type_proto="0x2f" + elif [ "$type" = "vxlan" ] || [ "$type" = "geneve" ]; then + tunnel_type_proto="0x11" + fi + if [ "$outer" = "4" ]; then + tunnel_type_offset="9" + if [ "$inner" = "4" ]; then + req_proto_offset="47" + req_offset="58" + if [ "$type" = "vxlan" ] || [ "$type" = "geneve" ]; then + req_proto_offset="$((req_proto_offset + 12))" + req_offset="$((req_offset + 12))" + fi + if $vlan; then + req_proto_offset="$((req_proto_offset + 4))" + req_offset="$((req_offset + 4))" + fi + out="$(tcpdump --immediate-mode -p -c 1 -v -i veth0 -n \ + ip[$tunnel_type_offset] = $tunnel_type_proto and \ + ip[$req_proto_offset] = 0x01 and \ + ip[$req_offset] = 0x08 2>/dev/null | head -n 1)" + elif [ "$inner" = "6" ]; then + req_proto_offset="44" + req_offset="78" + if [ "$type" = "vxlan" ] || [ "$type" = "geneve" ]; then + req_proto_offset="$((req_proto_offset + 12))" + req_offset="$((req_offset + 12))" + fi + if $vlan; then + req_proto_offset="$((req_proto_offset + 4))" + req_offset="$((req_offset + 4))" + fi + out="$(tcpdump --immediate-mode -p -c 1 -v -i veth0 -n \ + ip[$tunnel_type_offset] = $tunnel_type_proto and \ + ip[$req_proto_offset] = 0x3a and \ + ip[$req_offset] = 0x80 2>/dev/null | head -n 1)" + elif [ "$inner" = "other" ]; then + req_proto_offset="36" + req_offset="45" + if [ "$type" = "vxlan" ] || [ "$type" = "geneve" ]; then + req_proto_offset="$((req_proto_offset + 12))" + req_offset="$((req_offset + 12))" + fi + if $vlan; then + req_proto_offset="$((req_proto_offset + 4))" + req_offset="$((req_offset + 4))" + fi + if [ "$tos_ttl" = "inherit" ]; then + expected_tos="0x00" + expected_ttl="64" + fi + out="$(tcpdump --immediate-mode -p -c 1 -v -i veth0 -n \ + ip[$tunnel_type_offset] = $tunnel_type_proto and \ + ip[$req_proto_offset] = 0x08 and \ + ip[$((req_proto_offset + 1))] = 0x06 and \ + ip[$req_offset] = 0x01 2>/dev/null | head -n 1)" + fi + elif [ "$outer" = "6" ]; then + if [ "$type" = "gre" ]; then + tunnel_type_offset="40" + elif [ "$type" = "vxlan" ] || [ "$type" = "geneve" ]; then + tunnel_type_offset="6" + fi + if [ "$inner" = "4" ]; then + local req_proto_offset="75" + local req_offset="86" + if [ "$type" = "vxlan" ] || [ "$type" = "geneve" ]; then + req_proto_offset="$((req_proto_offset + 4))" + req_offset="$((req_offset + 4))" + fi + if $vlan; then + req_proto_offset="$((req_proto_offset + 4))" + req_offset="$((req_offset + 4))" + fi + out="$(tcpdump --immediate-mode -p -c 1 -v -i veth0 -n \ + ip6[$tunnel_type_offset] = $tunnel_type_proto and \ + ip6[$req_proto_offset] = 0x01 and \ + ip6[$req_offset] = 0x08 2>/dev/null | head -n 1)" + elif [ "$inner" = "6" ]; then + local req_proto_offset="72" + local req_offset="106" + if [ "$type" = "vxlan" ] || [ "$type" = "geneve" ]; then + req_proto_offset="$((req_proto_offset + 4))" + req_offset="$((req_offset + 4))" + fi + if $vlan; then + req_proto_offset="$((req_proto_offset + 4))" + req_offset="$((req_offset + 4))" + fi + out="$(tcpdump --immediate-mode -p -c 1 -v -i veth0 -n \ + ip6[$tunnel_type_offset] = $tunnel_type_proto and \ + ip6[$req_proto_offset] = 0x3a and \ + ip6[$req_offset] = 0x80 2>/dev/null | head -n 1)" + elif [ "$inner" = "other" ]; then + local req_proto_offset="64" + local req_offset="73" + if [ "$type" = "vxlan" ] || [ "$type" = "geneve" ]; then + req_proto_offset="$((req_proto_offset + 4))" + req_offset="$((req_offset + 4))" + fi + if $vlan; then + req_proto_offset="$((req_proto_offset + 4))" + req_offset="$((req_offset + 4))" + fi + if [ "$tos_ttl" = "inherit" ]; then + expected_tos="0x00" + expected_ttl="64" + fi + out="$(tcpdump --immediate-mode -p -c 1 -v -i veth0 -n \ + ip6[$tunnel_type_offset] = $tunnel_type_proto and \ + ip6[$req_proto_offset] = 0x08 and \ + ip6[$((req_proto_offset + 1))] = 0x06 and \ + ip6[$req_offset] = 0x01 2>/dev/null | head -n 1)" + fi + fi + kill -9 $ping_pid + wait $ping_pid 2>/dev/null + result="FAIL" + if [ "$outer" = "4" ]; then + captured_ttl="$(get_field "ttl" "$out")" + captured_tos="$(printf "0x%02x" "$(get_field "tos" "$out")")" + if [ "$captured_tos" = "$expected_tos" ] && + [ "$captured_ttl" = "$expected_ttl" ]; then + result="OK" + fi + elif [ "$outer" = "6" ]; then + captured_ttl="$(get_field "hlim" "$out")" + captured_tos="$(printf "0x%02x" "$(get_field "class" "$out")")" + if [ "$captured_tos" = "$expected_tos" ] && + [ "$captured_ttl" = "$expected_ttl" ]; then + result="OK" + fi + fi + + printf "%7s │\n" "$result" + if [ "$result" = "FAIL" ]; then + failed=true + if [ "$captured_tos" != "$expected_tos" ]; then + printf "│%43s%27s │\n" \ + "Expected TOS value: $expected_tos" \ + "Captured TOS value: $captured_tos" + fi + if [ "$captured_ttl" != "$expected_ttl" ]; then + printf "│%43s%27s │\n" \ + "Expected TTL value: $expected_ttl" \ + "Captured TTL value: $captured_ttl" + fi + printf "│%71s│\n" " " + fi +} + +cleanup() { + ip link del veth0 2>/dev/null + ip netns del testing 2>/dev/null + ip link del tep0 2>/dev/null +} + +printf "┌────────┬───────┬───────┬──────────────┬" +printf "──────────────┬───────┬────────┐\n" +for type in gre vxlan geneve; do + if ! $(modprobe "$type" 2>/dev/null); then + continue + fi + for outer in 4 6; do + printf "├────────┼───────┼───────┼──────────────┼" + printf "──────────────┼───────┼────────┤\n" + printf "│ Type │ outer | inner │ tos │" + printf " ttl │ vlan │ result │\n" + for inner in 4 6 other; do + printf "├────────┼───────┼───────┼──────────────┼" + printf "──────────────┼───────┼────────┤\n" + for tos_ttl in inherit random; do + for vlan in false true; do + setup "$type" "$outer" "$inner" \ + "$tos_ttl" "$vlan" + verify "$outer" "$inner" "$tos_ttl" \ + "$vlan" + cleanup + done + done + done + done +done +printf "└────────┴───────┴───────┴──────────────┴" +printf "──────────────┴───────┴────────┘\n" + +if $failed; then + exit 1 +fi -- 2.20.1