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#!/bin/bash
# SPDX-License-Identifier: GPL-2.0
#
# author: Jianguo Wu <wujianguo@chinatelecom.cn>
#
# Mostly copied from tools/testing/selftests/net/srv6_end_dt4_l3vpn_test.sh.
#
# This script is designed for testing the support of netfilter hooks for
# SRv6 End.DX4 behavior.
#
# Hereafter a network diagram is shown, where one tenants (named 100) offer
# IPv4 L3 VPN services allowing hosts to communicate with each other across
# an IPv6 network.
#
# Routers rt-1 and rt-2 implement IPv4 L3 VPN services leveraging the SRv6
# architecture. The key components for such VPNs are: a) SRv6 Encap behavior,
# b) SRv6 End.DX4 behavior.
#
# To explain how an IPv4 L3 VPN based on SRv6 works, let us briefly consider an
# example where, within the same domain of tenant 100, the host hs-1 pings
# the host hs-2.
#
# First of all, L2 reachability of the host hs-2 is taken into account by
# the router rt-1 which acts as an arp proxy.
#
# When the host hs-1 sends an IPv4 packet destined to hs-2, the router rt-1
# receives the packet on the internal veth-t100 interface, rt-1 contains the
# SRv6 Encap route for encapsulating the IPv4 packet in a IPv6 plus the Segment
# Routing Header (SRH) packet. This packet is sent through the (IPv6) core
# network up to the router rt-2 that receives it on veth0 interface.
#
# The rt-2 router uses the 'localsid' routing table to process incoming
# IPv6+SRH packets which belong to the VPN of the tenant 100. For each of these
# packets, the SRv6 End.DX4 behavior removes the outer IPv6+SRH headers and
# routs the packet to the specified nexthop. Afterwards, the packet is sent to
# the host hs-2 through the veth-t100 interface.
#
# The ping response follows the same processing but this time the role of rt-1
# and rt-2 are swapped.
#
# And when net.netfilter.nf_hooks_lwtunnel is set to 1 in rt-1 or rt-2, and a
# rpfilter iptables rule is added, SRv6 packets will go through netfilter PREROUTING
# hooks.
#
#
# +-------------------+ +-------------------+
# | | | |
# | hs-1 netns | | hs-2 netns |
# | | | |
# | +-------------+ | | +-------------+ |
# | | veth0 | | | | veth0 | |
# | | 10.0.0.1/24 | | | | 10.0.0.2/24 | |
# | +-------------+ | | +-------------+ |
# | . | | . |
# +-------------------+ +-------------------+
# . .
# . .
# . .
# +-----------------------------------+ +-----------------------------------+
# | . | | . |
# | +---------------+ | | +---------------- |
# | | veth-t100 | | | | veth-t100 | |
# | | 10.0.0.11/24 | +----------+ | | +----------+ | 10.0.0.22/24 | |
# | +-------+-------+ | route | | | | route | +-------+-------- |
# | | table | | | | table | |
# | +----------+ | | +----------+ |
# | +--------------+ | | +--------------+ |
# | | veth0 | | | | veth0 | |
# | | 2001:11::1/64 |.|...|.| 2001:11::2/64 | |
# | +--------------+ | | +--------------+ |
# | | | |
# | rt-1 netns | | rt-2 netns |
# | | | |
# +-----------------------------------+ +-----------------------------------+
#
# ~~~~~~~~~~~~~~~~~~~~~~~~~
# | Network configuration |
# ~~~~~~~~~~~~~~~~~~~~~~~~~
#
# rt-1: localsid table
# +----------------------------------------------------------------+
# |SID |Action |
# +----------------------------------------------------------------+
# |fc00:21:100::6004|apply SRv6 End.DX4 nh4 10.0.0.1 dev veth-t100 |
# +----------------------------------------------------------------+
#
# rt-1: route table
# +---------------------------------------------------+
# |host |Action |
# +---------------------------------------------------+
# |10.0.0.2 |apply seg6 encap segs fc00:12:100::6004|
# +---------------------------------------------------+
# |10.0.0.0/24|forward to dev veth_t100 |
# +---------------------------------------------------+
#
#
# rt-2: localsid table
# +---------------------------------------------------------------+
# |SID |Action |
# +---------------------------------------------------------------+
# |fc00:12:100::6004|apply SRv6 End.DX4 nh4 10.0.0.2 dev veth-t100|
# +---------------------------------------------------------------+
#
# rt-2: route table
# +---------------------------------------------------+
# |host |Action |
# +---------------------------------------------------+
# |10.0.0.1 |apply seg6 encap segs fc00:21:100::6004|
# +---------------------------------------------------+
# |10.0.0.0/24|forward to dev veth_t100 |
# +---------------------------------------------------+
#
# Kselftest framework requirement - SKIP code is 4.
ksft_skip=4
readonly IPv6_RT_NETWORK=2001:11
readonly IPv4_HS_NETWORK=10.0.0
readonly SID_LOCATOR=fc00
PING_TIMEOUT_SEC=4
ret=0
PAUSE_ON_FAIL=${PAUSE_ON_FAIL:=no}
log_test()
{
local rc=$1
local expected=$2
local msg="$3"
if [ ${rc} -eq ${expected} ]; then
nsuccess=$((nsuccess+1))
printf "\n TEST: %-60s [ OK ]\n" "${msg}"
else
ret=1
nfail=$((nfail+1))
printf "\n TEST: %-60s [FAIL]\n" "${msg}"
if [ "${PAUSE_ON_FAIL}" = "yes" ]; then
echo
echo "hit enter to continue, 'q' to quit"
read a
[ "$a" = "q" ] && exit 1
fi
fi
}
print_log_test_results()
{
if [ "$TESTS" != "none" ]; then
printf "\nTests passed: %3d\n" ${nsuccess}
printf "Tests failed: %3d\n" ${nfail}
fi
}
log_section()
{
echo
echo "################################################################################"
echo "TEST SECTION: $*"
echo "################################################################################"
}
cleanup()
{
ip link del veth-rt-1 2>/dev/null || true
ip link del veth-rt-2 2>/dev/null || true
# destroy routers rt-* and hosts hs-*
for ns in $(ip netns show | grep -E 'rt-*|hs-*'); do
ip netns del ${ns} || true
done
}
# Setup the basic networking for the routers
setup_rt_networking()
{
local rt=$1
local nsname=rt-${rt}
ip netns add ${nsname}
ip netns exec ${nsname} sysctl -wq net.ipv6.conf.all.accept_dad=0
ip netns exec ${nsname} sysctl -wq net.ipv6.conf.default.accept_dad=0
ip link set veth-rt-${rt} netns ${nsname}
ip -netns ${nsname} link set veth-rt-${rt} name veth0
ip -netns ${nsname} addr add ${IPv6_RT_NETWORK}::${rt}/64 dev veth0 nodad
ip -netns ${nsname} link set veth0 up
ip -netns ${nsname} link set lo up
ip netns exec ${nsname} sysctl -wq net.ipv4.ip_forward=1
ip netns exec ${nsname} sysctl -wq net.ipv6.conf.all.forwarding=1
}
setup_rt_netfilter()
{
local rt=$1
local nsname=rt-${rt}
ip netns exec ${nsname} sysctl -wq net.netfilter.nf_hooks_lwtunnel=1
ip netns exec ${nsname} iptables -t raw -A PREROUTING -m rpfilter --invert -j DROP
}
setup_hs()
{
local hs=$1
local rt=$2
local tid=$3
local hsname=hs-${hs}
local rtname=rt-${rt}
local rtveth=veth-t${tid}
# set the networking for the host
ip netns add ${hsname}
ip -netns ${hsname} link add veth0 type veth peer name ${rtveth}
ip -netns ${hsname} link set ${rtveth} netns ${rtname}
ip -netns ${hsname} addr add ${IPv4_HS_NETWORK}.${hs}/24 dev veth0
ip -netns ${hsname} link set veth0 up
ip -netns ${hsname} link set lo up
ip -netns ${rtname} addr add ${IPv4_HS_NETWORK}.${rt}${hs}/24 dev ${rtveth}
ip -netns ${rtname} link set ${rtveth} up
ip netns exec ${rtname} sysctl -wq net.ipv4.conf.${rtveth}.proxy_arp=1
}
setup_vpn_config()
{
local hssrc=$1
local rtsrc=$2
local hsdst=$3
local rtdst=$4
local tid=$5
local hssrc_name=hs-t${tid}-${hssrc}
local hsdst_name=hs-t${tid}-${hsdst}
local rtsrc_name=rt-${rtsrc}
local rtdst_name=rt-${rtdst}
local vpn_sid=${SID_LOCATOR}:${hssrc}${hsdst}:${tid}::6004
# set the encap route for encapsulating packets which arrive from the
# host hssrc and destined to the access router rtsrc.
ip -netns ${rtsrc_name} -4 route add ${IPv4_HS_NETWORK}.${hsdst}/32 \
encap seg6 mode encap segs ${vpn_sid} dev veth0
ip -netns ${rtsrc_name} -6 route add ${vpn_sid}/128 \
via 2001:11::${rtdst} dev veth0
# set the decap route for decapsulating packets which arrive from
# the rtdst router and destined to the hsdst host.
ip -netns ${rtdst_name} -6 route add ${vpn_sid}/128 \
encap seg6local action End.DX4 nh4 ${IPv4_HS_NETWORK}.${hsdst} dev veth-t${tid}
}
setup()
{
ip link add veth-rt-1 type veth peer name veth-rt-2
# setup the networking for router rt-1 and router rt-2
setup_rt_networking 1
setup_rt_networking 2
# setup two hosts for the tenant 100.
# - host hs-1 is directly connected to the router rt-1;
# - host hs-2 is directly connected to the router rt-2.
setup_hs 1 1 100
setup_hs 2 2 100
# setup the IPv4 L3 VPN which connects the host hs-1 and host hs-2.
setup_vpn_config 1 1 2 2 100 #args: src_host src_router dst_host dst_router tenant
setup_vpn_config 2 2 1 1 100
}
check_hs_connectivity()
{
local hssrc=$1
local hsdst=$2
local tid=$3
ip netns exec hs-${hssrc} ping -c 1 -W ${PING_TIMEOUT_SEC} \
${IPv4_HS_NETWORK}.${hsdst} >/dev/null 2>&1
}
check_and_log_hs_connectivity()
{
local hssrc=$1
local hsdst=$2
local tid=$3
check_hs_connectivity ${hssrc} ${hsdst} ${tid}
log_test $? 0 "Hosts connectivity: hs-${hssrc} -> hs-${hsdst} (tenant ${tid})"
}
host_tests()
{
log_section "SRv6 VPN connectivity test among hosts in the same tenant"
check_and_log_hs_connectivity 1 2 100
check_and_log_hs_connectivity 2 1 100
}
router_netfilter_tests()
{
log_section "SRv6 VPN connectivity test with netfilter enabled in routers"
setup_rt_netfilter 1
setup_rt_netfilter 2
check_and_log_hs_connectivity 1 2 100
check_and_log_hs_connectivity 2 1 100
}
if [ "$(id -u)" -ne 0 ];then
echo "SKIP: Need root privileges"
exit $ksft_skip
fi
if [ ! -x "$(command -v ip)" ]; then
echo "SKIP: Could not run test without ip tool"
exit $ksft_skip
fi
cleanup &>/dev/null
setup
host_tests
router_netfilter_tests
print_log_test_results
cleanup &>/dev/null
exit ${ret}
|
