Commit 221200ff authored by Jianguo Wu's avatar Jianguo Wu Committed by Pablo Neira Ayuso
Browse files

selftests: add selftest for the SRv6 End.DX6 behavior with netfilter 



this selftest is designed for evaluating the SRv6 End.DX6 behavior
used with netfilter(rpfilter), in this example, for implementing
IPv6 L3 VPN use cases.

Signed-off-by: default avatarJianguo Wu <wujianguo@chinatelecom.cn>
Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
parent 72e50ef9

tools/testing/selftests/net/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -44,6 +44,7 @@ TEST_PROGS += srv6_end_next_csid_l3vpn_test.sh 
TEST_PROGS += srv6_end_x_next_csid_l3vpn_test.sh

TEST_PROGS += srv6_end_flavors_test.sh

TEST_PROGS += srv6_end_dx4_netfilter_test.sh

TEST_PROGS += srv6_end_dx6_netfilter_test.sh

TEST_PROGS += vrf_strict_mode_test.sh

TEST_PROGS += arp_ndisc_evict_nocarrier.sh

TEST_PROGS += ndisc_unsolicited_na_test.sh

tools/testing/selftests/net/config

+1 −0
Original line number Diff line number Diff line
@@ -102,3 +102,4 @@ CONFIG_CRYPTO_ARIA=y 
CONFIG_XFRM_INTERFACE=m

CONFIG_XFRM_USER=m

CONFIG_IP_NF_MATCH_RPFILTER=m

CONFIG_IP6_NF_MATCH_RPFILTER=m

tools/testing/selftests/net/srv6_end_dx6_netfilter_test.sh

0 → 100755
+340 −0
Original line number Diff line number Diff line 
#!/bin/bash

# SPDX-License-Identifier: GPL-2.0

#

# author: Jianguo Wu <wujianguo@chinatelecom.cn>

#

# Mostly copied from tools/testing/selftests/net/srv6_end_dt6_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

# IPv6 L3 VPN services allowing hosts to communicate with each other across

# an IPv6 network.

#

# Routers rt-1 and rt-2 implement IPv6 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 IPv6 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 IPv6 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 IPv6 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    |  |

# |  | cafe::1/64  |  |                                   |  | cafe::2/64  |  |

# |  +-------------+  |                                   |  +-------------+  |

# |        .          |                                   |         .         |

# +-------------------+                                   +-------------------+

#          .                                                        .

#          .                                                        .

#          .                                                        .

# +-----------------------------------+   +-----------------------------------+

# |        .                          |   |                         .         |

# | +---------------+                 |   |                 +---------------- |

# | |   veth-t100   |                 |   |                 |   veth-t100   | |

# | | cafe::11/64   |    +----------+ |   | +----------+    | cafe::22/64   | |

# | +-------+-------+   |   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.DX6 nh6 cafe::1 dev veth-t100  |

# +----------------------------------------------------------------+

#

# rt-1: route table

# +---------------------------------------------------+

# |host       |Action                                 |

# +---------------------------------------------------+

# |cafe::2    |apply seg6 encap segs fc00:12:100::6004|

# +---------------------------------------------------+

# |cafe::/64  |forward to dev veth_t100               |

# +---------------------------------------------------+

#

#

# rt-2: localsid table

# +---------------------------------------------------------------+

# |SID              |Action                                       |

# +---------------------------------------------------------------+

# |fc00:12:100::6004|apply SRv6 End.DX6 nh6 cafe::2 dev veth-t100 |

# +---------------------------------------------------------------+

#

# rt-2: route table

# +---------------------------------------------------+

# |host       |Action                                 |

# +---------------------------------------------------+

# |cafe::1    |apply seg6 encap segs fc00:21:100::6004|

# +---------------------------------------------------+

# |cafe::/64  |forward to dev veth_t100               |

# +---------------------------------------------------+

#



# Kselftest framework requirement - SKIP code is 4.

ksft_skip=4



readonly IPv6_RT_NETWORK=2001:11

readonly IPv6_HS_NETWORK=cafe

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.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} ip6tables -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 ${IPv6_HS_NETWORK}::${hs}/64 dev veth0 nodad

	ip -netns ${hsname} link set veth0 up

	ip -netns ${hsname} link set lo up



	ip -netns ${rtname} addr add ${IPv6_HS_NETWORK}::${rt}${hs}/64 dev ${rtveth}

	ip -netns ${rtname} link set ${rtveth} up



	ip netns exec ${rtname} sysctl -wq net.ipv6.conf.all.accept_dad=0

	ip netns exec ${rtname} sysctl -wq net.ipv6.conf.default.accept_dad=0



	ip netns exec ${rtname} sysctl -wq net.ipv6.conf.${rtveth}.proxy_ndp=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 rtveth=veth-t${tid}

	local vpn_sid=${SID_LOCATOR}:${hssrc}${hsdst}:${tid}::6004



	ip -netns ${rtsrc_name} -6 neigh add proxy ${IPv6_HS_NETWORK}::${hsdst} dev ${rtveth}



	# set the encap route for encapsulating packets which arrive from the

	# host hssrc and destined to the access router rtsrc.

	ip -netns ${rtsrc_name} -6 route add ${IPv6_HS_NETWORK}::${hsdst}/128 \

		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.DX6 nh6 ${IPv6_HS_NETWORK}::${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 -6 -c 1 -W ${PING_TIMEOUT_SEC} \

		${IPv6_HS_NETWORK}::${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}