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|
#!/bin/sh
# SPDX-License-Identifier: GPL-2.0
#
# Check that route PMTU values match expectations, and that initial device MTU
# values are assigned correctly
#
# Tests currently implemented:
#
# - pmtu_ipv4
# Set up two namespaces, A and B, with two paths between them over routers
# R1 and R2 (also implemented with namespaces), with different MTUs:
#
# segment a_r1 segment b_r1 a_r1: 2000
# .--------------R1--------------. a_r2: 1500
# A B a_r3: 2000
# '--------------R2--------------' a_r4: 1400
# segment a_r2 segment b_r2
#
# Check that PMTU exceptions with the correct PMTU are created. Then
# decrease and increase the MTU of the local link for one of the paths,
# A to R1, checking that route exception PMTU changes accordingly over
# this path. Also check that locked exceptions are created when an ICMP
# message advertising a PMTU smaller than net.ipv4.route.min_pmtu is
# received
#
# - pmtu_ipv6
# Same as pmtu_ipv4, except for locked PMTU tests, using IPv6
#
# - pmtu_ipv4_vxlan4_exception
# Set up the same network topology as pmtu_ipv4, create a VXLAN tunnel
# over IPv4 between A and B, routed via R1. On the link between R1 and B,
# set a MTU lower than the VXLAN MTU and the MTU on the link between A and
# R1. Send IPv4 packets, exceeding the MTU between R1 and B, over VXLAN
# from A to B and check that the PMTU exception is created with the right
# value on A
#
# - pmtu_ipv6_vxlan4_exception
# Same as pmtu_ipv4_vxlan4_exception, but send IPv6 packets from A to B
#
# - pmtu_ipv4_vxlan6_exception
# Same as pmtu_ipv4_vxlan4_exception, but use IPv6 transport from A to B
#
# - pmtu_ipv6_vxlan6_exception
# Same as pmtu_ipv4_vxlan6_exception, but send IPv6 packets from A to B
#
# - pmtu_ipv4_geneve4_exception
# Same as pmtu_ipv4_vxlan4_exception, but using a GENEVE tunnel instead of
# VXLAN
#
# - pmtu_ipv6_geneve4_exception
# Same as pmtu_ipv6_vxlan4_exception, but using a GENEVE tunnel instead of
# VXLAN
#
# - pmtu_ipv4_geneve6_exception
# Same as pmtu_ipv4_vxlan6_exception, but using a GENEVE tunnel instead of
# VXLAN
#
# - pmtu_ipv6_geneve6_exception
# Same as pmtu_ipv6_vxlan6_exception, but using a GENEVE tunnel instead of
# VXLAN
#
# - pmtu_ipv{4,6}_fou{4,6}_exception
# Same as pmtu_ipv4_vxlan4, but using a direct IPv4/IPv6 encapsulation
# (FoU) over IPv4/IPv6, instead of VXLAN
#
# - pmtu_ipv{4,6}_fou{4,6}_exception
# Same as pmtu_ipv4_vxlan4, but using a generic UDP IPv4/IPv6
# encapsulation (GUE) over IPv4/IPv6, instead of VXLAN
#
# - pmtu_vti4_exception
# Set up vti tunnel on top of veth, with xfrm states and policies, in two
# namespaces with matching endpoints. Check that route exception is not
# created if link layer MTU is not exceeded, then exceed it and check that
# exception is created with the expected PMTU. The approach described
# below for IPv6 doesn't apply here, because, on IPv4, administrative MTU
# changes alone won't affect PMTU
#
# - pmtu_vti6_exception
# Set up vti6 tunnel on top of veth, with xfrm states and policies, in two
# namespaces with matching endpoints. Check that route exception is
# created by exceeding link layer MTU with ping to other endpoint. Then
# decrease and increase MTU of tunnel, checking that route exception PMTU
# changes accordingly
#
# - pmtu_vti4_default_mtu
# Set up vti4 tunnel on top of veth, in two namespaces with matching
# endpoints. Check that MTU assigned to vti interface is the MTU of the
# lower layer (veth) minus additional lower layer headers (zero, for veth)
# minus IPv4 header length
#
# - pmtu_vti6_default_mtu
# Same as above, for IPv6
#
# - pmtu_vti4_link_add_mtu
# Set up vti4 interface passing MTU value at link creation, check MTU is
# configured, and that link is not created with invalid MTU values
#
# - pmtu_vti6_link_add_mtu
# Same as above, for IPv6
#
# - pmtu_vti6_link_change_mtu
# Set up two dummy interfaces with different MTUs, create a vti6 tunnel
# and check that configured MTU is used on link creation and changes, and
# that MTU is properly calculated instead when MTU is not configured from
# userspace
# Kselftest framework requirement - SKIP code is 4.
ksft_skip=4
# Some systems don't have a ping6 binary anymore
which ping6 > /dev/null 2>&1 && ping6=$(which ping6) || ping6=$(which ping)
tests="
pmtu_ipv4_exception ipv4: PMTU exceptions
pmtu_ipv6_exception ipv6: PMTU exceptions
pmtu_ipv4_vxlan4_exception IPv4 over vxlan4: PMTU exceptions
pmtu_ipv6_vxlan4_exception IPv6 over vxlan4: PMTU exceptions
pmtu_ipv4_vxlan6_exception IPv4 over vxlan6: PMTU exceptions
pmtu_ipv6_vxlan6_exception IPv6 over vxlan6: PMTU exceptions
pmtu_ipv4_geneve4_exception IPv4 over geneve4: PMTU exceptions
pmtu_ipv6_geneve4_exception IPv6 over geneve4: PMTU exceptions
pmtu_ipv4_geneve6_exception IPv4 over geneve6: PMTU exceptions
pmtu_ipv6_geneve6_exception IPv6 over geneve6: PMTU exceptions
pmtu_ipv4_fou4_exception IPv4 over fou4: PMTU exceptions
pmtu_ipv6_fou4_exception IPv6 over fou4: PMTU exceptions
pmtu_ipv4_fou6_exception IPv4 over fou6: PMTU exceptions
pmtu_ipv6_fou6_exception IPv6 over fou6: PMTU exceptions
pmtu_ipv4_gue4_exception IPv4 over gue4: PMTU exceptions
pmtu_ipv6_gue4_exception IPv6 over gue4: PMTU exceptions
pmtu_ipv4_gue6_exception IPv4 over gue6: PMTU exceptions
pmtu_ipv6_gue6_exception IPv6 over gue6: PMTU exceptions
pmtu_vti6_exception vti6: PMTU exceptions
pmtu_vti4_exception vti4: PMTU exceptions
pmtu_vti4_default_mtu vti4: default MTU assignment
pmtu_vti6_default_mtu vti6: default MTU assignment
pmtu_vti4_link_add_mtu vti4: MTU setting on link creation
pmtu_vti6_link_add_mtu vti6: MTU setting on link creation
pmtu_vti6_link_change_mtu vti6: MTU changes on link changes"
NS_A="ns-$(mktemp -u XXXXXX)"
NS_B="ns-$(mktemp -u XXXXXX)"
NS_R1="ns-$(mktemp -u XXXXXX)"
NS_R2="ns-$(mktemp -u XXXXXX)"
ns_a="ip netns exec ${NS_A}"
ns_b="ip netns exec ${NS_B}"
ns_r1="ip netns exec ${NS_R1}"
ns_r2="ip netns exec ${NS_R2}"
# Addressing and routing for tests with routers: four network segments, with
# index SEGMENT between 1 and 4, a common prefix (PREFIX4 or PREFIX6) and an
# identifier ID, which is 1 for hosts (A and B), 2 for routers (R1 and R2).
# Addresses are:
# - IPv4: PREFIX4.SEGMENT.ID (/24)
# - IPv6: PREFIX6:SEGMENT::ID (/64)
prefix4="10.0"
prefix6="fc00"
a_r1=1
a_r2=2
b_r1=3
b_r2=4
# ns peer segment
routing_addrs="
A R1 ${a_r1}
A R2 ${a_r2}
B R1 ${b_r1}
B R2 ${b_r2}
"
# Traffic from A to B goes through R1 by default, and through R2, if destined to
# B's address on the b_r2 segment.
# Traffic from B to A goes through R1.
# ns destination gateway
routes="
A default ${prefix4}.${a_r1}.2
A ${prefix4}.${b_r2}.1 ${prefix4}.${a_r2}.2
B default ${prefix4}.${b_r1}.2
A default ${prefix6}:${a_r1}::2
A ${prefix6}:${b_r2}::1 ${prefix6}:${a_r2}::2
B default ${prefix6}:${b_r1}::2
"
veth4_a_addr="192.168.1.1"
veth4_b_addr="192.168.1.2"
veth4_mask="24"
veth6_a_addr="fd00:1::a"
veth6_b_addr="fd00:1::b"
veth6_mask="64"
tunnel4_a_addr="192.168.2.1"
tunnel4_b_addr="192.168.2.2"
tunnel4_mask="24"
tunnel6_a_addr="fd00:2::a"
tunnel6_b_addr="fd00:2::b"
tunnel6_mask="64"
dummy6_0_addr="fc00:1000::0"
dummy6_1_addr="fc00:1001::0"
dummy6_mask="64"
cleanup_done=1
err_buf=
tcpdump_pids=
err() {
err_buf="${err_buf}${1}
"
}
err_flush() {
echo -n "${err_buf}"
err_buf=
}
# Find the auto-generated name for this namespace
nsname() {
eval echo \$NS_$1
}
setup_fou_or_gue() {
outer="${1}"
inner="${2}"
encap="${3}"
if [ "${outer}" = "4" ]; then
modprobe fou || return 2
a_addr="<
|