xref: /linux/tools/testing/selftests/net/pmtu.sh (revision b7d3826c2ed6c3e626e7ae796c5df2c0d2551c6a)
1#!/bin/sh
2# SPDX-License-Identifier: GPL-2.0
3#
4# Check that route PMTU values match expectations, and that initial device MTU
5# values are assigned correctly
6#
7# Tests currently implemented:
8#
9# - pmtu_ipv4
10#	Set up two namespaces, A and B, with two paths between them over routers
11#	R1 and R2 (also implemented with namespaces), with different MTUs:
12#
13#	  segment a_r1    segment b_r1		a_r1: 2000
14#	.--------------R1--------------.	a_r2: 1500
15#	A                               B	a_r3: 2000
16#	'--------------R2--------------'	a_r4: 1400
17#	  segment a_r2    segment b_r2
18#
19#	Check that PMTU exceptions with the correct PMTU are created. Then
20#	decrease and increase the MTU of the local link for one of the paths,
21#	A to R1, checking that route exception PMTU changes accordingly over
22#	this path. Also check that locked exceptions are created when an ICMP
23#	message advertising a PMTU smaller than net.ipv4.route.min_pmtu is
24#	received
25#
26# - pmtu_ipv6
27#	Same as pmtu_ipv4, except for locked PMTU tests, using IPv6
28#
29# - pmtu_vti4_exception
30#	Set up vti tunnel on top of veth, with xfrm states and policies, in two
31#	namespaces with matching endpoints. Check that route exception is not
32#	created if link layer MTU is not exceeded, then exceed it and check that
33#	exception is created with the expected PMTU. The approach described
34#	below for IPv6 doesn't apply here, because, on IPv4, administrative MTU
35#	changes alone won't affect PMTU
36#
37# - pmtu_vti6_exception
38#	Set up vti6 tunnel on top of veth, with xfrm states and policies, in two
39#	namespaces with matching endpoints. Check that route exception is
40#	created by exceeding link layer MTU with ping to other endpoint. Then
41#	decrease and increase MTU of tunnel, checking that route exception PMTU
42#	changes accordingly
43#
44# - pmtu_vti4_default_mtu
45#	Set up vti4 tunnel on top of veth, in two namespaces with matching
46#	endpoints. Check that MTU assigned to vti interface is the MTU of the
47#	lower layer (veth) minus additional lower layer headers (zero, for veth)
48#	minus IPv4 header length
49#
50# - pmtu_vti6_default_mtu
51#	Same as above, for IPv6
52#
53# - pmtu_vti4_link_add_mtu
54#	Set up vti4 interface passing MTU value at link creation, check MTU is
55#	configured, and that link is not created with invalid MTU values
56#
57# - pmtu_vti6_link_add_mtu
58#	Same as above, for IPv6
59#
60# - pmtu_vti6_link_change_mtu
61#	Set up two dummy interfaces with different MTUs, create a vti6 tunnel
62#	and check that configured MTU is used on link creation and changes, and
63#	that MTU is properly calculated instead when MTU is not configured from
64#	userspace
65
66# Kselftest framework requirement - SKIP code is 4.
67ksft_skip=4
68
69# Some systems don't have a ping6 binary anymore
70which ping6 > /dev/null 2>&1 && ping6=$(which ping6) || ping6=$(which ping)
71
72tests="
73	pmtu_ipv4_exception		ipv4: PMTU exceptions
74	pmtu_ipv6_exception		ipv6: PMTU exceptions
75	pmtu_vti6_exception		vti6: PMTU exceptions
76	pmtu_vti4_exception		vti4: PMTU exceptions
77	pmtu_vti4_default_mtu		vti4: default MTU assignment
78	pmtu_vti6_default_mtu		vti6: default MTU assignment
79	pmtu_vti4_link_add_mtu		vti4: MTU setting on link creation
80	pmtu_vti6_link_add_mtu		vti6: MTU setting on link creation
81	pmtu_vti6_link_change_mtu	vti6: MTU changes on link changes"
82
83NS_A="ns-$(mktemp -u XXXXXX)"
84NS_B="ns-$(mktemp -u XXXXXX)"
85NS_R1="ns-$(mktemp -u XXXXXX)"
86NS_R2="ns-$(mktemp -u XXXXXX)"
87ns_a="ip netns exec ${NS_A}"
88ns_b="ip netns exec ${NS_B}"
89ns_r1="ip netns exec ${NS_R1}"
90ns_r2="ip netns exec ${NS_R2}"
91
92# Addressing and routing for tests with routers: four network segments, with
93# index SEGMENT between 1 and 4, a common prefix (PREFIX4 or PREFIX6) and an
94# identifier ID, which is 1 for hosts (A and B), 2 for routers (R1 and R2).
95# Addresses are:
96# - IPv4: PREFIX4.SEGMENT.ID (/24)
97# - IPv6: PREFIX6:SEGMENT::ID (/64)
98prefix4="192.168"
99prefix6="fd00"
100a_r1=1
101a_r2=2
102b_r1=3
103b_r2=4
104#	ns	peer	segment
105routing_addrs="
106	A	R1	${a_r1}
107	A	R2	${a_r2}
108	B	R1	${b_r1}
109	B	R2	${b_r2}
110"
111# Traffic from A to B goes through R1 by default, and through R2, if destined to
112# B's address on the b_r2 segment.
113# Traffic from B to A goes through R1.
114#	ns	destination		gateway
115routes="
116	A	default			${prefix4}.${a_r1}.2
117	A	${prefix4}.${b_r2}.1	${prefix4}.${a_r2}.2
118	B	default			${prefix4}.${b_r1}.2
119
120	A	default			${prefix6}:${a_r1}::2
121	A	${prefix6}:${b_r2}::1	${prefix6}:${a_r2}::2
122	B	default			${prefix6}:${b_r1}::2
123"
124
125veth4_a_addr="192.168.1.1"
126veth4_b_addr="192.168.1.2"
127veth4_mask="24"
128veth6_a_addr="fd00:1::a"
129veth6_b_addr="fd00:1::b"
130veth6_mask="64"
131
132vti4_a_addr="192.168.2.1"
133vti4_b_addr="192.168.2.2"
134vti4_mask="24"
135vti6_a_addr="fd00:2::a"
136vti6_b_addr="fd00:2::b"
137vti6_mask="64"
138
139dummy6_0_addr="fc00:1000::0"
140dummy6_1_addr="fc00:1001::0"
141dummy6_mask="64"
142
143cleanup_done=1
144err_buf=
145
146err() {
147	err_buf="${err_buf}${1}
148"
149}
150
151err_flush() {
152	echo -n "${err_buf}"
153	err_buf=
154}
155
156# Find the auto-generated name for this namespace
157nsname() {
158	eval echo \$NS_$1
159}
160
161setup_namespaces() {
162	for n in ${NS_A} ${NS_B} ${NS_R1} ${NS_R2}; do
163		ip netns add ${n} || return 1
164	done
165}
166
167setup_veth() {
168	${ns_a} ip link add veth_a type veth peer name veth_b || return 1
169	${ns_a} ip link set veth_b netns ${NS_B}
170
171	${ns_a} ip addr add ${veth4_a_addr}/${veth4_mask} dev veth_a
172	${ns_b} ip addr add ${veth4_b_addr}/${veth4_mask} dev veth_b
173
174	${ns_a} ip addr add ${veth6_a_addr}/${veth6_mask} dev veth_a
175	${ns_b} ip addr add ${veth6_b_addr}/${veth6_mask} dev veth_b
176
177	${ns_a} ip link set veth_a up
178	${ns_b} ip link set veth_b up
179}
180
181setup_vti() {
182	proto=${1}
183	veth_a_addr="${2}"
184	veth_b_addr="${3}"
185	vti_a_addr="${4}"
186	vti_b_addr="${5}"
187	vti_mask=${6}
188
189	[ ${proto} -eq 6 ] && vti_type="vti6" || vti_type="vti"
190
191	${ns_a} ip link add vti${proto}_a type ${vti_type} local ${veth_a_addr} remote ${veth_b_addr} key 10 || return 1
192	${ns_b} ip link add vti${proto}_b type ${vti_type} local ${veth_b_addr} remote ${veth_a_addr} key 10
193
194	${ns_a} ip addr add ${vti_a_addr}/${vti_mask} dev vti${proto}_a
195	${ns_b} ip addr add ${vti_b_addr}/${vti_mask} dev vti${proto}_b
196
197	${ns_a} ip link set vti${proto}_a up
198	${ns_b} ip link set vti${proto}_b up
199
200	sleep 1
201}
202
203setup_vti4() {
204	setup_vti 4 ${veth4_a_addr} ${veth4_b_addr} ${vti4_a_addr} ${vti4_b_addr} ${vti4_mask}
205}
206
207setup_vti6() {
208	setup_vti 6 ${veth6_a_addr} ${veth6_b_addr} ${vti6_a_addr} ${vti6_b_addr} ${vti6_mask}
209}
210
211setup_xfrm() {
212	proto=${1}
213	veth_a_addr="${2}"
214	veth_b_addr="${3}"
215
216	${ns_a} ip -${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
217	${ns_a} ip -${proto} xfrm state add src ${veth_b_addr} dst ${veth_a_addr} spi 0x1001 proto esp aead "rfc4106(gcm(aes))" 0x0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f 128 mode tunnel
218	${ns_a} ip -${proto} xfrm policy add dir out mark 10 tmpl src ${veth_a_addr} dst ${veth_b_addr} proto esp mode tunnel
219	${ns_a} ip -${proto} xfrm policy add dir in mark 10 tmpl src ${veth_b_addr} dst ${veth_a_addr} proto esp mode tunnel
220
221	${ns_b} ip -${proto} xfrm state add src ${veth_a_addr} dst ${veth_b_addr} spi 0x1000 proto esp aead "rfc4106(gcm(aes))" 0x0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f 128 mode tunnel
222	${ns_b} ip -${proto} xfrm state add src ${veth_b_addr} dst ${veth_a_addr} spi 0x1001 proto esp aead "rfc4106(gcm(aes))" 0x0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f 128 mode tunnel
223	${ns_b} ip -${proto} xfrm policy add dir out mark 10 tmpl src ${veth_b_addr} dst ${veth_a_addr} proto esp mode tunnel
224	${ns_b} ip -${proto} xfrm policy add dir in mark 10 tmpl src ${veth_a_addr} dst ${veth_b_addr} proto esp mode tunnel
225}
226
227setup_xfrm4() {
228	setup_xfrm 4 ${veth4_a_addr} ${veth4_b_addr}
229}
230
231setup_xfrm6() {
232	setup_xfrm 6 ${veth6_a_addr} ${veth6_b_addr}
233}
234
235setup_routing() {
236	for i in ${NS_R1} ${NS_R2}; do
237		ip netns exec ${i} sysctl -q net/ipv4/ip_forward=1
238		ip netns exec ${i} sysctl -q net/ipv6/conf/all/forwarding=1
239	done
240
241	for i in ${routing_addrs}; do
242		[ "${ns}" = "" ]	&& ns="${i}"		&& continue
243		[ "${peer}" = "" ]	&& peer="${i}"		&& continue
244		[ "${segment}" = "" ]	&& segment="${i}"
245
246		ns_name="$(nsname ${ns})"
247		peer_name="$(nsname ${peer})"
248		if="veth_${ns}-${peer}"
249		ifpeer="veth_${peer}-${ns}"
250
251		# Create veth links
252		ip link add ${if} up netns ${ns_name} type veth peer name ${ifpeer} netns ${peer_name} || return 1
253		ip -n ${peer_name} link set dev ${ifpeer} up
254
255		# Add addresses
256		ip -n ${ns_name}   addr add ${prefix4}.${segment}.1/24  dev ${if}
257		ip -n ${ns_name}   addr add ${prefix6}:${segment}::1/64 dev ${if}
258
259		ip -n ${peer_name} addr add ${prefix4}.${segment}.2/24  dev ${ifpeer}
260		ip -n ${peer_name} addr add ${prefix6}:${segment}::2/64 dev ${ifpeer}
261
262		ns=""; peer=""; segment=""
263	done
264
265	for i in ${routes}; do
266		[ "${ns}" = "" ]	&& ns="${i}"		&& continue
267		[ "${addr}" = "" ]	&& addr="${i}"		&& continue
268		[ "${gw}" = "" ]	&& gw="${i}"
269
270		ns_name="$(nsname ${ns})"
271
272		ip -n ${ns_name} route add ${addr} via ${gw}
273
274		ns=""; addr=""; gw=""
275	done
276}
277
278setup() {
279	[ "$(id -u)" -ne 0 ] && echo "  need to run as root" && return $ksft_skip
280
281	cleanup_done=0
282	for arg do
283		eval setup_${arg} || { echo "  ${arg} not supported"; return 1; }
284	done
285}
286
287cleanup() {
288	[ ${cleanup_done} -eq 1 ] && return
289	for n in ${NS_A} ${NS_B} ${NS_R1} ${NS_R2}; do
290		ip netns del ${n} 2> /dev/null
291	done
292	cleanup_done=1
293}
294
295mtu() {
296	ns_cmd="${1}"
297	dev="${2}"
298	mtu="${3}"
299
300	${ns_cmd} ip link set dev ${dev} mtu ${mtu}
301}
302
303mtu_parse() {
304	input="${1}"
305
306	next=0
307	for i in ${input}; do
308		[ ${next} -eq 1 -a "${i}" = "lock" ] && next=2 && continue
309		[ ${next} -eq 1 ] && echo "${i}" && return
310		[ ${next} -eq 2 ] && echo "lock ${i}" && return
311		[ "${i}" = "mtu" ] && next=1
312	done
313}
314
315link_get() {
316	ns_cmd="${1}"
317	name="${2}"
318
319	${ns_cmd} ip link show dev "${name}"
320}
321
322link_get_mtu() {
323	ns_cmd="${1}"
324	name="${2}"
325
326	mtu_parse "$(link_get "${ns_cmd}" ${name})"
327}
328
329route_get_dst_exception() {
330	ns_cmd="${1}"
331	dst="${2}"
332
333	${ns_cmd} ip route get "${dst}"
334}
335
336route_get_dst_pmtu_from_exception() {
337	ns_cmd="${1}"
338	dst="${2}"
339
340	mtu_parse "$(route_get_dst_exception "${ns_cmd}" ${dst})"
341}
342
343check_pmtu_value() {
344	expected="${1}"
345	value="${2}"
346	event="${3}"
347
348	[ "${expected}" = "any" ] && [ -n "${value}" ] && return 0
349	[ "${value}" = "${expected}" ] && return 0
350	[ -z "${value}" ] &&    err "  PMTU exception wasn't created after ${event}" && return 1
351	[ -z "${expected}" ] && err "  PMTU exception shouldn't exist after ${event}" && return 1
352	err "  found PMTU exception with incorrect MTU ${value}, expected ${expected}, after ${event}"
353	return 1
354}
355
356test_pmtu_ipvX() {
357	family=${1}
358
359	setup namespaces routing || return 2
360
361	if [ ${family} -eq 4 ]; then
362		ping=ping
363		dst1="${prefix4}.${b_r1}.1"
364		dst2="${prefix4}.${b_r2}.1"
365	else
366		ping=${ping6}
367		dst1="${prefix6}:${b_r1}::1"
368		dst2="${prefix6}:${b_r2}::1"
369	fi
370
371	# Set up initial MTU values
372	mtu "${ns_a}"  veth_A-R1 2000
373	mtu "${ns_r1}" veth_R1-A 2000
374	mtu "${ns_r1}" veth_R1-B 1400
375	mtu "${ns_b}"  veth_B-R1 1400
376
377	mtu "${ns_a}"  veth_A-R2 2000
378	mtu "${ns_r2}" veth_R2-A 2000
379	mtu "${ns_r2}" veth_R2-B 1500
380	mtu "${ns_b}"  veth_B-R2 1500
381
382	# Create route exceptions
383	${ns_a} ${ping} -q -M want -i 0.1 -w 2 -s 1800 ${dst1} > /dev/null
384	${ns_a} ${ping} -q -M want -i 0.1 -w 2 -s 1800 ${dst2} > /dev/null
385
386	# Check that exceptions have been created with the correct PMTU
387	pmtu_1="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst1})"
388	check_pmtu_value "1400" "${pmtu_1}" "exceeding MTU" || return 1
389	pmtu_2="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst2})"
390	check_pmtu_value "1500" "${pmtu_2}" "exceeding MTU" || return 1
391
392	# Decrease local MTU below PMTU, check for PMTU decrease in route exception
393	mtu "${ns_a}"  veth_A-R1 1300
394	mtu "${ns_r1}" veth_R1-A 1300
395	pmtu_1="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst1})"
396	check_pmtu_value "1300" "${pmtu_1}" "decreasing local MTU" || return 1
397	# Second exception shouldn't be modified
398	pmtu_2="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst2})"
399	check_pmtu_value "1500" "${pmtu_2}" "changing local MTU on a link not on this path" || return 1
400
401	# Increase MTU, check for PMTU increase in route exception
402	mtu "${ns_a}"  veth_A-R1 1700
403	mtu "${ns_r1}" veth_R1-A 1700
404	pmtu_1="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst1})"
405	check_pmtu_value "1700" "${pmtu_1}" "increasing local MTU" || return 1
406	# Second exception shouldn't be modified
407	pmtu_2="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst2})"
408	check_pmtu_value "1500" "${pmtu_2}" "changing local MTU on a link not on this path" || return 1
409
410	# Skip PMTU locking tests for IPv6
411	[ $family -eq 6 ] && return 0
412
413	# Decrease remote MTU on path via R2, get new exception
414	mtu "${ns_r2}" veth_R2-B 400
415	mtu "${ns_b}"  veth_B-R2 400
416	${ns_a} ${ping} -q -M want -i 0.1 -w 2 -s 1400 ${dst2} > /dev/null
417	pmtu_2="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst2})"
418	check_pmtu_value "lock 552" "${pmtu_2}" "exceeding MTU, with MTU < min_pmtu" || return 1
419
420	# Decrease local MTU below PMTU
421	mtu "${ns_a}"  veth_A-R2 500
422	mtu "${ns_r2}" veth_R2-A 500
423	pmtu_2="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst2})"
424	check_pmtu_value "500" "${pmtu_2}" "decreasing local MTU" || return 1
425
426	# Increase local MTU
427	mtu "${ns_a}"  veth_A-R2 1500
428	mtu "${ns_r2}" veth_R2-A 1500
429	pmtu_2="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst2})"
430	check_pmtu_value "1500" "${pmtu_2}" "increasing local MTU" || return 1
431
432	# Get new exception
433	${ns_a} ${ping} -q -M want -i 0.1 -w 2 -s 1400 ${dst2} > /dev/null
434	pmtu_2="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst2})"
435	check_pmtu_value "lock 552" "${pmtu_2}" "exceeding MTU, with MTU < min_pmtu" || return 1
436}
437
438test_pmtu_ipv4_exception() {
439	test_pmtu_ipvX 4
440}
441
442test_pmtu_ipv6_exception() {
443	test_pmtu_ipvX 6
444}
445
446test_pmtu_vti4_exception() {
447	setup namespaces veth vti4 xfrm4 || return 2
448
449	veth_mtu=1500
450	vti_mtu=$((veth_mtu - 20))
451
452	#                                SPI   SN   IV  ICV   pad length   next header
453	esp_payload_rfc4106=$((vti_mtu - 4   - 4  - 8 - 16  - 1          - 1))
454	ping_payload=$((esp_payload_rfc4106 - 28))
455
456	mtu "${ns_a}" veth_a ${veth_mtu}
457	mtu "${ns_b}" veth_b ${veth_mtu}
458	mtu "${ns_a}" vti4_a ${vti_mtu}
459	mtu "${ns_b}" vti4_b ${vti_mtu}
460
461	# Send DF packet without exceeding link layer MTU, check that no
462	# exception is created
463	${ns_a} ping -q -M want -i 0.1 -w 2 -s ${ping_payload} ${vti4_b_addr} > /dev/null
464	pmtu="$(route_get_dst_pmtu_from_exception "${ns_a}" ${vti4_b_addr})"
465	check_pmtu_value "" "${pmtu}" "sending packet smaller than PMTU (IP payload length ${esp_payload_rfc4106})" || return 1
466
467	# Now exceed link layer MTU by one byte, check that exception is created
468	# with the right PMTU value
469	${ns_a} ping -q -M want -i 0.1 -w 2 -s $((ping_payload + 1)) ${vti4_b_addr} > /dev/null
470	pmtu="$(route_get_dst_pmtu_from_exception "${ns_a}" ${vti4_b_addr})"
471	check_pmtu_value "${esp_payload_rfc4106}" "${pmtu}" "exceeding PMTU (IP payload length $((esp_payload_rfc4106 + 1)))"
472}
473
474test_pmtu_vti6_exception() {
475	setup namespaces veth vti6 xfrm6 || return 2
476	fail=0
477
478	# Create route exception by exceeding link layer MTU
479	mtu "${ns_a}" veth_a 4000
480	mtu "${ns_b}" veth_b 4000
481	mtu "${ns_a}" vti6_a 5000
482	mtu "${ns_b}" vti6_b 5000
483	${ns_a} ${ping6} -q -i 0.1 -w 2 -s 60000 ${vti6_b_addr} > /dev/null
484
485	# Check that exception was created
486	pmtu="$(route_get_dst_pmtu_from_exception "${ns_a}" ${vti6_b_addr})"
487	check_pmtu_value any "${pmtu}" "creating tunnel exceeding link layer MTU" || return 1
488
489	# Decrease tunnel MTU, check for PMTU decrease in route exception
490	mtu "${ns_a}" vti6_a 3000
491	pmtu="$(route_get_dst_pmtu_from_exception "${ns_a}" ${vti6_b_addr})"
492	check_pmtu_value "3000" "${pmtu}" "decreasing tunnel MTU" || fail=1
493
494	# Increase tunnel MTU, check for PMTU increase in route exception
495	mtu "${ns_a}" vti6_a 9000
496	pmtu="$(route_get_dst_pmtu_from_exception "${ns_a}" ${vti6_b_addr})"
497	check_pmtu_value "9000" "${pmtu}" "increasing tunnel MTU" || fail=1
498
499	return ${fail}
500}
501
502test_pmtu_vti4_default_mtu() {
503	setup namespaces veth vti4 || return 2
504
505	# Check that MTU of vti device is MTU of veth minus IPv4 header length
506	veth_mtu="$(link_get_mtu "${ns_a}" veth_a)"
507	vti4_mtu="$(link_get_mtu "${ns_a}" vti4_a)"
508	if [ $((veth_mtu - vti4_mtu)) -ne 20 ]; then
509		err "  vti MTU ${vti4_mtu} is not veth MTU ${veth_mtu} minus IPv4 header length"
510		return 1
511	fi
512}
513
514test_pmtu_vti6_default_mtu() {
515	setup namespaces veth vti6 || return 2
516
517	# Check that MTU of vti device is MTU of veth minus IPv6 header length
518	veth_mtu="$(link_get_mtu "${ns_a}" veth_a)"
519	vti6_mtu="$(link_get_mtu "${ns_a}" vti6_a)"
520	if [ $((veth_mtu - vti6_mtu)) -ne 40 ]; then
521		err "  vti MTU ${vti6_mtu} is not veth MTU ${veth_mtu} minus IPv6 header length"
522		return 1
523	fi
524}
525
526test_pmtu_vti4_link_add_mtu() {
527	setup namespaces || return 2
528
529	${ns_a} ip link add vti4_a type vti local ${veth4_a_addr} remote ${veth4_b_addr} key 10
530	[ $? -ne 0 ] && err "  vti not supported" && return 2
531	${ns_a} ip link del vti4_a
532
533	fail=0
534
535	min=68
536	max=$((65535 - 20))
537	# Check invalid values first
538	for v in $((min - 1)) $((max + 1)); do
539		${ns_a} ip link add vti4_a mtu ${v} type vti local ${veth4_a_addr} remote ${veth4_b_addr} key 10 2>/dev/null
540		# This can fail, or MTU can be adjusted to a proper value
541		[ $? -ne 0 ] && continue
542		mtu="$(link_get_mtu "${ns_a}" vti4_a)"
543		if [ ${mtu} -lt ${min} -o ${mtu} -gt ${max} ]; then
544			err "  vti tunnel created with invalid MTU ${mtu}"
545			fail=1
546		fi
547		${ns_a} ip link del vti4_a
548	done
549
550	# Now check valid values
551	for v in ${min} 1300 ${max}; do
552		${ns_a} ip link add vti4_a mtu ${v} type vti local ${veth4_a_addr} remote ${veth4_b_addr} key 10
553		mtu="$(link_get_mtu "${ns_a}" vti4_a)"
554		${ns_a} ip link del vti4_a
555		if [ "${mtu}" != "${v}" ]; then
556			err "  vti MTU ${mtu} doesn't match configured value ${v}"
557			fail=1
558		fi
559	done
560
561	return ${fail}
562}
563
564test_pmtu_vti6_link_add_mtu() {
565	setup namespaces || return 2
566
567	${ns_a} ip link add vti6_a type vti6 local ${veth6_a_addr} remote ${veth6_b_addr} key 10
568	[ $? -ne 0 ] && err "  vti6 not supported" && return 2
569	${ns_a} ip link del vti6_a
570
571	fail=0
572
573	min=68			# vti6 can carry IPv4 packets too
574	max=$((65535 - 40))
575	# Check invalid values first
576	for v in $((min - 1)) $((max + 1)); do
577		${ns_a} ip link add vti6_a mtu ${v} type vti6 local ${veth6_a_addr} remote ${veth6_b_addr} key 10 2>/dev/null
578		# This can fail, or MTU can be adjusted to a proper value
579		[ $? -ne 0 ] && continue
580		mtu="$(link_get_mtu "${ns_a}" vti6_a)"
581		if [ ${mtu} -lt ${min} -o ${mtu} -gt ${max} ]; then
582			err "  vti6 tunnel created with invalid MTU ${v}"
583			fail=1
584		fi
585		${ns_a} ip link del vti6_a
586	done
587
588	# Now check valid values
589	for v in 68 1280 1300 $((65535 - 40)); do
590		${ns_a} ip link add vti6_a mtu ${v} type vti6 local ${veth6_a_addr} remote ${veth6_b_addr} key 10
591		mtu="$(link_get_mtu "${ns_a}" vti6_a)"
592		${ns_a} ip link del vti6_a
593		if [ "${mtu}" != "${v}" ]; then
594			err "  vti6 MTU ${mtu} doesn't match configured value ${v}"
595			fail=1
596		fi
597	done
598
599	return ${fail}
600}
601
602test_pmtu_vti6_link_change_mtu() {
603	setup namespaces || return 2
604
605	${ns_a} ip link add dummy0 mtu 1500 type dummy
606	[ $? -ne 0 ] && err "  dummy not supported" && return 2
607	${ns_a} ip link add dummy1 mtu 3000 type dummy
608	${ns_a} ip link set dummy0 up
609	${ns_a} ip link set dummy1 up
610
611	${ns_a} ip addr add ${dummy6_0_addr}/${dummy6_mask} dev dummy0
612	${ns_a} ip addr add ${dummy6_1_addr}/${dummy6_mask} dev dummy1
613
614	fail=0
615
616	# Create vti6 interface bound to device, passing MTU, check it
617	${ns_a} ip link add vti6_a mtu 1300 type vti6 remote ${dummy6_0_addr} local ${dummy6_0_addr}
618	mtu="$(link_get_mtu "${ns_a}" vti6_a)"
619	if [ ${mtu} -ne 1300 ]; then
620		err "  vti6 MTU ${mtu} doesn't match configured value 1300"
621		fail=1
622	fi
623
624	# Move to another device with different MTU, without passing MTU, check
625	# MTU is adjusted
626	${ns_a} ip link set vti6_a type vti6 remote ${dummy6_1_addr} local ${dummy6_1_addr}
627	mtu="$(link_get_mtu "${ns_a}" vti6_a)"
628	if [ ${mtu} -ne $((3000 - 40)) ]; then
629		err "  vti MTU ${mtu} is not dummy MTU 3000 minus IPv6 header length"
630		fail=1
631	fi
632
633	# Move it back, passing MTU, check MTU is not overridden
634	${ns_a} ip link set vti6_a mtu 1280 type vti6 remote ${dummy6_0_addr} local ${dummy6_0_addr}
635	mtu="$(link_get_mtu "${ns_a}" vti6_a)"
636	if [ ${mtu} -ne 1280 ]; then
637		err "  vti6 MTU ${mtu} doesn't match configured value 1280"
638		fail=1
639	fi
640
641	return ${fail}
642}
643
644trap cleanup EXIT
645
646exitcode=0
647desc=0
648IFS="
649"
650for t in ${tests}; do
651	[ $desc -eq 0 ] && name="${t}" && desc=1 && continue || desc=0
652
653	(
654		unset IFS
655		eval test_${name}
656		ret=$?
657		cleanup
658
659		if [ $ret -eq 0 ]; then
660			printf "TEST: %-60s  [ OK ]\n" "${t}"
661		elif [ $ret -eq 1 ]; then
662			printf "TEST: %-60s  [FAIL]\n" "${t}"
663			err_flush
664			exit 1
665		elif [ $ret -eq 2 ]; then
666			printf "TEST: %-60s  [SKIP]\n" "${t}"
667			err_flush
668		fi
669	)
670	[ $? -ne 0 ] && exitcode=1
671done
672
673exit ${exitcode}
674