1#!/bin/bash
2# SPDX-License-Identifier: GPL-2.0
3#
4# author: Andrea Mayer <andrea.mayer@uniroma2.it>
5# author: Paolo Lungaroni <paolo.lungaroni@cnit.it>
6
7# This test is designed for evaluating the new SRv6 End.DT6 behavior used for
8# implementing IPv6 L3 VPN use cases.
9#
10# Hereafter a network diagram is shown, where two different tenants (named 100
11# and 200) offer IPv6 L3 VPN services allowing hosts to communicate with each
12# other across an IPv6 network.
13#
14# Only hosts belonging to the same tenant (and to the same VPN) can communicate
15# with each other. Instead, the communication among hosts of different tenants
16# is forbidden.
17# In other words, hosts hs-t100-1 and hs-t100-2 are connected through the IPv6
18# L3 VPN of tenant 100 while hs-t200-3 and hs-t200-4 are connected using the
19# IPv6 L3 VPN of tenant 200. Cross connection between tenant 100 and tenant 200
20# is forbidden and thus, for example, hs-t100-1 cannot reach hs-t200-3 and vice
21# versa.
22#
23# Routers rt-1 and rt-2 implement IPv6 L3 VPN services leveraging the SRv6
24# architecture. The key components for such VPNs are: a) SRv6 Encap behavior,
25# b) SRv6 End.DT6 behavior and c) VRF.
26#
27# To explain how an IPv6 L3 VPN based on SRv6 works, let us briefly consider an
28# example where, within the same domain of tenant 100, the host hs-t100-1 pings
29# the host hs-t100-2.
30#
31# First of all, L2 reachability of the host hs-t100-2 is taken into account by
32# the router rt-1 which acts as a ndp proxy.
33#
34# When the host hs-t100-1 sends an IPv6 packet destined to hs-t100-2, the
35# router rt-1 receives the packet on the internal veth-t100 interface. Such
36# interface is enslaved to the VRF vrf-100 whose associated table contains the
37# SRv6 Encap route for encapsulating any IPv6 packet in a IPv6 plus the Segment
38# Routing Header (SRH) packet. This packet is sent through the (IPv6) core
39# network up to the router rt-2 that receives it on veth0 interface.
40#
41# The rt-2 router uses the 'localsid' routing table to process incoming
42# IPv6+SRH packets which belong to the VPN of the tenant 100. For each of these
43# packets, the SRv6 End.DT6 behavior removes the outer IPv6+SRH headers and
44# performs the lookup on the vrf-100 table using the destination address of
45# the decapsulated IPv6 packet. Afterwards, the packet is sent to the host
46# hs-t100-2 through the veth-t100 interface.
47#
48# The ping response follows the same processing but this time the role of rt-1
49# and rt-2 are swapped.
50#
51# Of course, the IPv6 L3 VPN for tenant 200 works exactly as the IPv6 L3 VPN
52# for tenant 100. In this case, only hosts hs-t200-3 and hs-t200-4 are able to
53# connect with each other.
54#
55#
56# +-------------------+                                   +-------------------+
57# |                   |                                   |                   |
58# |  hs-t100-1 netns  |                                   |  hs-t100-2 netns  |
59# |                   |                                   |                   |
60# |  +-------------+  |                                   |  +-------------+  |
61# |  |    veth0    |  |                                   |  |    veth0    |  |
62# |  |  cafe::1/64 |  |                                   |  |  cafe::2/64 |  |
63# |  +-------------+  |                                   |  +-------------+  |
64# |        .          |                                   |         .         |
65# +-------------------+                                   +-------------------+
66#          .                                                        .
67#          .                                                        .
68#          .                                                        .
69# +-----------------------------------+   +-----------------------------------+
70# |        .                          |   |                         .         |
71# | +---------------+                 |   |                 +---------------- |
72# | |   veth-t100   |                 |   |                 |   veth-t100   | |
73# | |  cafe::254/64 |    +----------+ |   | +----------+    |  cafe::254/64 | |
74# | +-------+-------+    | localsid | |   | | localsid |    +-------+-------- |
75# |         |            |   table  | |   | |   table  |            |         |
76# |    +----+----+       +----------+ |   | +----------+       +----+----+    |
77# |    | vrf-100 |                    |   |                    | vrf-100 |    |
78# |    +---------+     +------------+ |   | +------------+     +---------+    |
79# |                    |   veth0    | |   | |   veth0    |                    |
80# |                    | fd00::1/64 |.|...|.| fd00::2/64 |                    |
81# |    +---------+     +------------+ |   | +------------+     +---------+    |
82# |    | vrf-200 |                    |   |                    | vrf-200 |    |
83# |    +----+----+                    |   |                    +----+----+    |
84# |         |                         |   |                         |         |
85# | +-------+-------+                 |   |                 +-------+-------- |
86# | |   veth-t200   |                 |   |                 |   veth-t200   | |
87# | |  cafe::254/64 |                 |   |                 |  cafe::254/64 | |
88# | +---------------+      rt-1 netns |   | rt-2 netns      +---------------- |
89# |        .                          |   |                          .        |
90# +-----------------------------------+   +-----------------------------------+
91#          .                                                         .
92#          .                                                         .
93#          .                                                         .
94#          .                                                         .
95# +-------------------+                                   +-------------------+
96# |        .          |                                   |          .        |
97# |  +-------------+  |                                   |  +-------------+  |
98# |  |    veth0    |  |                                   |  |    veth0    |  |
99# |  |  cafe::3/64 |  |                                   |  |  cafe::4/64 |  |
100# |  +-------------+  |                                   |  +-------------+  |
101# |                   |                                   |                   |
102# |  hs-t200-3 netns  |                                   |  hs-t200-4 netns  |
103# |                   |                                   |                   |
104# +-------------------+                                   +-------------------+
105#
106#
107# ~~~~~~~~~~~~~~~~~~~~~~~~~
108# | Network configuration |
109# ~~~~~~~~~~~~~~~~~~~~~~~~~
110#
111# rt-1: localsid table (table 90)
112# +-------------------------------------------------+
113# |SID              |Action                         |
114# +-------------------------------------------------+
115# |fc00:21:100::6006|apply SRv6 End.DT6 vrftable 100|
116# +-------------------------------------------------+
117# |fc00:21:200::6006|apply SRv6 End.DT6 vrftable 200|
118# +-------------------------------------------------+
119#
120# rt-1: VRF tenant 100 (table 100)
121# +---------------------------------------------------+
122# |host       |Action                                 |
123# +---------------------------------------------------+
124# |cafe::2    |apply seg6 encap segs fc00:12:100::6006|
125# +---------------------------------------------------+
126# |cafe::/64  |forward to dev veth_t100               |
127# +---------------------------------------------------+
128#
129# rt-1: VRF tenant 200 (table 200)
130# +---------------------------------------------------+
131# |host       |Action                                 |
132# +---------------------------------------------------+
133# |cafe::4    |apply seg6 encap segs fc00:12:200::6006|
134# +---------------------------------------------------+
135# |cafe::/64  |forward to dev veth_t200               |
136# +---------------------------------------------------+
137#
138#
139# rt-2: localsid table (table 90)
140# +-------------------------------------------------+
141# |SID              |Action                         |
142# +-------------------------------------------------+
143# |fc00:12:100::6006|apply SRv6 End.DT6 vrftable 100|
144# +-------------------------------------------------+
145# |fc00:12:200::6006|apply SRv6 End.DT6 vrftable 200|
146# +-------------------------------------------------+
147#
148# rt-2: VRF tenant 100 (table 100)
149# +---------------------------------------------------+
150# |host       |Action                                 |
151# +---------------------------------------------------+
152# |cafe::1    |apply seg6 encap segs fc00:21:100::6006|
153# +---------------------------------------------------+
154# |cafe::/64  |forward to dev veth_t100               |
155# +---------------------------------------------------+
156#
157# rt-2: VRF tenant 200 (table 200)
158# +---------------------------------------------------+
159# |host       |Action                                 |
160# +---------------------------------------------------+
161# |cafe::3    |apply seg6 encap segs fc00:21:200::6006|
162# +---------------------------------------------------+
163# |cafe::/64  |forward to dev veth_t200               |
164# +---------------------------------------------------+
165#
166
167readonly LOCALSID_TABLE_ID=90
168readonly IPv6_RT_NETWORK=fd00
169readonly IPv6_HS_NETWORK=cafe
170readonly VPN_LOCATOR_SERVICE=fc00
171PING_TIMEOUT_SEC=4
172
173ret=0
174
175PAUSE_ON_FAIL=${PAUSE_ON_FAIL:=no}
176
177log_test()
178{
179	local rc=$1
180	local expected=$2
181	local msg="$3"
182
183	if [ ${rc} -eq ${expected} ]; then
184		nsuccess=$((nsuccess+1))
185		printf "\n    TEST: %-60s  [ OK ]\n" "${msg}"
186	else
187		ret=1
188		nfail=$((nfail+1))
189		printf "\n    TEST: %-60s  [FAIL]\n" "${msg}"
190		if [ "${PAUSE_ON_FAIL}" = "yes" ]; then
191			echo
192			echo "hit enter to continue, 'q' to quit"
193			read a
194			[ "$a" = "q" ] && exit 1
195		fi
196	fi
197}
198
199print_log_test_results()
200{
201	if [ "$TESTS" != "none" ]; then
202		printf "\nTests passed: %3d\n" ${nsuccess}
203		printf "Tests failed: %3d\n"   ${nfail}
204	fi
205}
206
207log_section()
208{
209	echo
210	echo "################################################################################"
211	echo "TEST SECTION: $*"
212	echo "################################################################################"
213}
214
215cleanup()
216{
217	ip link del veth-rt-1 2>/dev/null || true
218	ip link del veth-rt-2 2>/dev/null || true
219
220	# destroy routers rt-* and hosts hs-*
221	for ns in $(ip netns show | grep -E 'rt-*|hs-*'); do
222		ip netns del ${ns} || true
223	done
224}
225
226# Setup the basic networking for the routers
227setup_rt_networking()
228{
229	local rt=$1
230	local nsname=rt-${rt}
231
232	ip netns add ${nsname}
233	ip link set veth-rt-${rt} netns ${nsname}
234	ip -netns ${nsname} link set veth-rt-${rt} name veth0
235
236	ip netns exec ${nsname} sysctl -wq net.ipv6.conf.all.accept_dad=0
237	ip netns exec ${nsname} sysctl -wq net.ipv6.conf.default.accept_dad=0
238
239	ip -netns ${nsname} addr add ${IPv6_RT_NETWORK}::${rt}/64 dev veth0 nodad
240	ip -netns ${nsname} link set veth0 up
241	ip -netns ${nsname} link set lo up
242
243	ip netns exec ${nsname} sysctl -wq net.ipv6.conf.all.forwarding=1
244}
245
246setup_hs()
247{
248	local hs=$1
249	local rt=$2
250	local tid=$3
251	local hsname=hs-t${tid}-${hs}
252	local rtname=rt-${rt}
253	local rtveth=veth-t${tid}
254
255	# set the networking for the host
256	ip netns add ${hsname}
257
258	ip netns exec ${hsname} sysctl -wq net.ipv6.conf.all.accept_dad=0
259	ip netns exec ${hsname} sysctl -wq net.ipv6.conf.default.accept_dad=0
260
261	ip -netns ${hsname} link add veth0 type veth peer name ${rtveth}
262	ip -netns ${hsname} link set ${rtveth} netns ${rtname}
263	ip -netns ${hsname} addr add ${IPv6_HS_NETWORK}::${hs}/64 dev veth0 nodad
264	ip -netns ${hsname} link set veth0 up
265	ip -netns ${hsname} link set lo up
266
267	# configure the VRF for the tenant X on the router which is directly
268	# connected to the source host.
269	ip -netns ${rtname} link add vrf-${tid} type vrf table ${tid}
270	ip -netns ${rtname} link set vrf-${tid} up
271
272	ip netns exec ${rtname} sysctl -wq net.ipv6.conf.all.accept_dad=0
273	ip netns exec ${rtname} sysctl -wq net.ipv6.conf.default.accept_dad=0
274
275	# enslave the veth-tX interface to the vrf-X in the access router
276	ip -netns ${rtname} link set ${rtveth} master vrf-${tid}
277	ip -netns ${rtname} addr add ${IPv6_HS_NETWORK}::254/64 dev ${rtveth} nodad
278	ip -netns ${rtname} link set ${rtveth} up
279
280	ip netns exec ${rtname} sysctl -wq net.ipv6.conf.${rtveth}.proxy_ndp=1
281
282	ip netns exec ${rtname} sh -c "echo 1 > /proc/sys/net/vrf/strict_mode"
283}
284
285setup_vpn_config()
286{
287	local hssrc=$1
288	local rtsrc=$2
289	local hsdst=$3
290	local rtdst=$4
291	local tid=$5
292
293	local hssrc_name=hs-t${tid}-${hssrc}
294	local hsdst_name=hs-t${tid}-${hsdst}
295	local rtsrc_name=rt-${rtsrc}
296	local rtdst_name=rt-${rtdst}
297	local rtveth=veth-t${tid}
298	local vpn_sid=${VPN_LOCATOR_SERVICE}:${hssrc}${hsdst}:${tid}::6006
299
300	ip -netns ${rtsrc_name} -6 neigh add proxy ${IPv6_HS_NETWORK}::${hsdst} dev ${rtveth}
301
302	# set the encap route for encapsulating packets which arrive from the
303	# host hssrc and destined to the access router rtsrc.
304	ip -netns ${rtsrc_name} -6 route add ${IPv6_HS_NETWORK}::${hsdst}/128 vrf vrf-${tid} \
305		encap seg6 mode encap segs ${vpn_sid} dev veth0
306	ip -netns ${rtsrc_name} -6 route add ${vpn_sid}/128 vrf vrf-${tid} \
307		via fd00::${rtdst} dev veth0
308
309	# set the decap route for decapsulating packets which arrive from
310	# the rtdst router and destined to the hsdst host.
311	ip -netns ${rtdst_name} -6 route add ${vpn_sid}/128 table ${LOCALSID_TABLE_ID} \
312		encap seg6local action End.DT6 vrftable ${tid} dev vrf-${tid}
313
314	# all sids for VPNs start with a common locator which is fc00::/16.
315	# Routes for handling the SRv6 End.DT6 behavior instances are grouped
316	# together in the 'localsid' table.
317	#
318	# NOTE: added only once
319	if [ -z "$(ip -netns ${rtdst_name} -6 rule show | \
320	    grep "to ${VPN_LOCATOR_SERVICE}::/16 lookup ${LOCALSID_TABLE_ID}")" ]; then
321		ip -netns ${rtdst_name} -6 rule add \
322			to ${VPN_LOCATOR_SERVICE}::/16 \
323			lookup ${LOCALSID_TABLE_ID} prio 999
324	fi
325}
326
327setup()
328{
329	ip link add veth-rt-1 type veth peer name veth-rt-2
330	# setup the networking for router rt-1 and router rt-2
331	setup_rt_networking 1
332	setup_rt_networking 2
333
334	# setup two hosts for the tenant 100.
335	#  - host hs-1 is directly connected to the router rt-1;
336	#  - host hs-2 is directly connected to the router rt-2.
337	setup_hs 1 1 100  #args: host router tenant
338	setup_hs 2 2 100
339
340	# setup two hosts for the tenant 200
341	#  - host hs-3 is directly connected to the router rt-1;
342	#  - host hs-4 is directly connected to the router rt-2.
343	setup_hs 3 1 200
344	setup_hs 4 2 200
345
346	# setup the IPv6 L3 VPN which connects the host hs-t100-1 and host
347	# hs-t100-2 within the same tenant 100.
348	setup_vpn_config 1 1 2 2 100  #args: src_host src_router dst_host dst_router tenant
349	setup_vpn_config 2 2 1 1 100
350
351	# setup the IPv6 L3 VPN which connects the host hs-t200-3 and host
352	# hs-t200-4 within the same tenant 200.
353	setup_vpn_config 3 1 4 2 200
354	setup_vpn_config 4 2 3 1 200
355}
356
357check_rt_connectivity()
358{
359	local rtsrc=$1
360	local rtdst=$2
361
362	ip netns exec rt-${rtsrc} ping -c 1 -W 1 ${IPv6_RT_NETWORK}::${rtdst} \
363		>/dev/null 2>&1
364}
365
366check_and_log_rt_connectivity()
367{
368	local rtsrc=$1
369	local rtdst=$2
370
371	check_rt_connectivity ${rtsrc} ${rtdst}
372	log_test $? 0 "Routers connectivity: rt-${rtsrc} -> rt-${rtdst}"
373}
374
375check_hs_connectivity()
376{
377	local hssrc=$1
378	local hsdst=$2
379	local tid=$3
380
381	ip netns exec hs-t${tid}-${hssrc} ping -c 1 -W ${PING_TIMEOUT_SEC} \
382		${IPv6_HS_NETWORK}::${hsdst} >/dev/null 2>&1
383}
384
385check_and_log_hs_connectivity()
386{
387	local hssrc=$1
388	local hsdst=$2
389	local tid=$3
390
391	check_hs_connectivity ${hssrc} ${hsdst} ${tid}
392	log_test $? 0 "Hosts connectivity: hs-t${tid}-${hssrc} -> hs-t${tid}-${hsdst} (tenant ${tid})"
393}
394
395check_and_log_hs_isolation()
396{
397	local hssrc=$1
398	local tidsrc=$2
399	local hsdst=$3
400	local tiddst=$4
401
402	check_hs_connectivity ${hssrc} ${hsdst} ${tidsrc}
403	# NOTE: ping should fail
404	log_test $? 1 "Hosts isolation: hs-t${tidsrc}-${hssrc} -X-> hs-t${tiddst}-${hsdst}"
405}
406
407
408check_and_log_hs2gw_connectivity()
409{
410	local hssrc=$1
411	local tid=$2
412
413	check_hs_connectivity ${hssrc} 254 ${tid}
414	log_test $? 0 "Hosts connectivity: hs-t${tid}-${hssrc} -> gw (tenant ${tid})"
415}
416
417router_tests()
418{
419	log_section "IPv6 routers connectivity test"
420
421	check_and_log_rt_connectivity 1 2
422	check_and_log_rt_connectivity 2 1
423}
424
425host2gateway_tests()
426{
427	log_section "IPv6 connectivity test among hosts and gateway"
428
429	check_and_log_hs2gw_connectivity 1 100
430	check_and_log_hs2gw_connectivity 2 100
431
432	check_and_log_hs2gw_connectivity 3 200
433	check_and_log_hs2gw_connectivity 4 200
434}
435
436host_vpn_tests()
437{
438	log_section "SRv6 VPN connectivity test among hosts in the same tenant"
439
440	check_and_log_hs_connectivity 1 2 100
441	check_and_log_hs_connectivity 2 1 100
442
443	check_and_log_hs_connectivity 3 4 200
444	check_and_log_hs_connectivity 4 3 200
445}
446
447host_vpn_isolation_tests()
448{
449	local i
450	local j
451	local k
452	local tmp
453	local l1="1 2"
454	local l2="3 4"
455	local t1=100
456	local t2=200
457
458	log_section "SRv6 VPN isolation test among hosts in different tentants"
459
460	for k in 0 1; do
461		for i in ${l1}; do
462			for j in ${l2}; do
463				check_and_log_hs_isolation ${i} ${t1} ${j} ${t2}
464			done
465		done
466
467		# let us test the reverse path
468		tmp="${l1}"; l1="${l2}"; l2="${tmp}"
469		tmp=${t1}; t1=${t2}; t2=${tmp}
470	done
471}
472
473if [ "$(id -u)" -ne 0 ];then
474	echo "SKIP: Need root privileges"
475	exit 0
476fi
477
478if [ ! -x "$(command -v ip)" ]; then
479	echo "SKIP: Could not run test without ip tool"
480	exit 0
481fi
482
483modprobe vrf &>/dev/null
484if [ ! -e /proc/sys/net/vrf/strict_mode ]; then
485        echo "SKIP: vrf sysctl does not exist"
486        exit 0
487fi
488
489cleanup &>/dev/null
490
491setup
492
493router_tests
494host2gateway_tests
495host_vpn_tests
496host_vpn_isolation_tests
497
498print_log_test_results
499
500cleanup &>/dev/null
501
502exit ${ret}
503