#
# 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_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
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_vti6_exception vti6: PMTU exceptions
pmtu_vti4_exception vti4: PMTU exceptions
pmtu_vti4_default_mtu vti4: default MTU assignment
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="192.168"
+prefix6="fd00"
+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"
err_buf=
}
+# Find the auto-generated name for this namespace
+nsname() {
+ eval echo \$NS_$1
+}
+
setup_namespaces() {
- ip netns add ${NS_A} || return 1
- ip netns add ${NS_B}
+ for n in ${NS_A} ${NS_B} ${NS_R1} ${NS_R2}; do
+ ip netns add ${n} || return 1
+ done
}
setup_veth() {
setup_xfrm 6 ${veth6_a_addr} ${veth6_b_addr}
}
+setup_routing() {
+ for i in ${NS_R1} ${NS_R2}; do
+ ip netns exec ${i} sysctl -q net/ipv4/ip_forward=1
+ ip netns exec ${i} sysctl -q net/ipv6/conf/all/forwarding=1
+ done
+
+ for i in ${routing_addrs}; do
+ [ "${ns}" = "" ] && ns="${i}" && continue
+ [ "${peer}" = "" ] && peer="${i}" && continue
+ [ "${segment}" = "" ] && segment="${i}"
+
+ ns_name="$(nsname ${ns})"
+ peer_name="$(nsname ${peer})"
+ if="veth_${ns}-${peer}"
+ ifpeer="veth_${peer}-${ns}"
+
+ # Create veth links
+ ip link add ${if} up netns ${ns_name} type veth peer name ${ifpeer} netns ${peer_name} || return 1
+ ip -n ${peer_name} link set dev ${ifpeer} up
+
+ # Add addresses
+ ip -n ${ns_name} addr add ${prefix4}.${segment}.1/24 dev ${if}
+ ip -n ${ns_name} addr add ${prefix6}:${segment}::1/64 dev ${if}
+
+ ip -n ${peer_name} addr add ${prefix4}.${segment}.2/24 dev ${ifpeer}
+ ip -n ${peer_name} addr add ${prefix6}:${segment}::2/64 dev ${ifpeer}
+
+ ns=""; peer=""; segment=""
+ done
+
+ for i in ${routes}; do
+ [ "${ns}" = "" ] && ns="${i}" && continue
+ [ "${addr}" = "" ] && addr="${i}" && continue
+ [ "${gw}" = "" ] && gw="${i}"
+
+ ns_name="$(nsname ${ns})"
+
+ ip -n ${ns_name} route add ${addr} via ${gw}
+
+ ns=""; addr=""; gw=""
+ done
+}
+
setup() {
[ "$(id -u)" -ne 0 ] && echo " need to run as root" && return $ksft_skip
cleanup() {
[ ${cleanup_done} -eq 1 ] && return
- ip netns del ${NS_A} 2> /dev/null
- ip netns del ${NS_B} 2> /dev/null
+ for n in ${NS_A} ${NS_B} ${NS_R1} ${NS_R2}; do
+ ip netns del ${n} 2> /dev/null
+ done
cleanup_done=1
}
return 1
}
+test_pmtu_ipvX() {
+ family=${1}
+
+ setup namespaces routing || return 2
+
+ if [ ${family} -eq 4 ]; then
+ ping=ping
+ dst1="${prefix4}.${b_r1}.1"
+ dst2="${prefix4}.${b_r2}.1"
+ else
+ ping=${ping6}
+ dst1="${prefix6}:${b_r1}::1"
+ dst2="${prefix6}:${b_r2}::1"
+ fi
+
+ # Set up initial MTU values
+ mtu "${ns_a}" veth_A-R1 2000
+ mtu "${ns_r1}" veth_R1-A 2000
+ mtu "${ns_r1}" veth_R1-B 1400
+ mtu "${ns_b}" veth_B-R1 1400
+
+ mtu "${ns_a}" veth_A-R2 2000
+ mtu "${ns_r2}" veth_R2-A 2000
+ mtu "${ns_r2}" veth_R2-B 1500
+ mtu "${ns_b}" veth_B-R2 1500
+
+ # Create route exceptions
+ ${ns_a} ${ping} -q -M want -i 0.1 -w 2 -s 1800 ${dst1} > /dev/null
+ ${ns_a} ${ping} -q -M want -i 0.1 -w 2 -s 1800 ${dst2} > /dev/null
+
+ # Check that exceptions have been created with the correct PMTU
+ pmtu_1="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst1})"
+ check_pmtu_value "1400" "${pmtu_1}" "exceeding MTU" || return 1
+ pmtu_2="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst2})"
+ check_pmtu_value "1500" "${pmtu_2}" "exceeding MTU" || return 1
+
+ # Decrease local MTU below PMTU, check for PMTU decrease in route exception
+ mtu "${ns_a}" veth_A-R1 1300
+ mtu "${ns_r1}" veth_R1-A 1300
+ pmtu_1="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst1})"
+ check_pmtu_value "1300" "${pmtu_1}" "decreasing local MTU" || return 1
+ # Second exception shouldn't be modified
+ pmtu_2="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst2})"
+ check_pmtu_value "1500" "${pmtu_2}" "changing local MTU on a link not on this path" || return 1
+
+ # Increase MTU, check for PMTU increase in route exception
+ mtu "${ns_a}" veth_A-R1 1700
+ mtu "${ns_r1}" veth_R1-A 1700
+ pmtu_1="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst1})"
+ check_pmtu_value "1700" "${pmtu_1}" "increasing local MTU" || return 1
+ # Second exception shouldn't be modified
+ pmtu_2="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst2})"
+ check_pmtu_value "1500" "${pmtu_2}" "changing local MTU on a link not on this path" || return 1
+
+ # Skip PMTU locking tests for IPv6
+ [ $family -eq 6 ] && return 0
+
+ # Decrease remote MTU on path via R2, get new exception
+ mtu "${ns_r2}" veth_R2-B 400
+ mtu "${ns_b}" veth_B-R2 400
+ ${ns_a} ${ping} -q -M want -i 0.1 -w 2 -s 1400 ${dst2} > /dev/null
+ pmtu_2="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst2})"
+ check_pmtu_value "lock 552" "${pmtu_2}" "exceeding MTU, with MTU < min_pmtu" || return 1
+
+ # Decrease local MTU below PMTU
+ mtu "${ns_a}" veth_A-R2 500
+ mtu "${ns_r2}" veth_R2-A 500
+ pmtu_2="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst2})"
+ check_pmtu_value "500" "${pmtu_2}" "decreasing local MTU" || return 1
+
+ # Increase local MTU
+ mtu "${ns_a}" veth_A-R2 1500
+ mtu "${ns_r2}" veth_R2-A 1500
+ pmtu_2="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst2})"
+ check_pmtu_value "1500" "${pmtu_2}" "increasing local MTU" || return 1
+
+ # Get new exception
+ ${ns_a} ${ping} -q -M want -i 0.1 -w 2 -s 1400 ${dst2} > /dev/null
+ pmtu_2="$(route_get_dst_pmtu_from_exception "${ns_a}" ${dst2})"
+ check_pmtu_value "lock 552" "${pmtu_2}" "exceeding MTU, with MTU < min_pmtu" || return 1
+}
+
+test_pmtu_ipv4_exception() {
+ test_pmtu_ipvX 4
+}
+
+test_pmtu_ipv6_exception() {
+ test_pmtu_ipvX 6
+}
+
test_pmtu_vti4_exception() {
setup namespaces veth vti4 xfrm4 || return 2