Add a test for the OVS datapath POP_VLAN action. The test uses the VLAN sub-interface of a veth pair to generate 802.1Q tagged frames and verifies that pop_vlan correctly strips the VLAN tag before delivery via pcap frame capture.
The test has two verifications: - Negative: forward tagged frames without pop_vlan, verify the VLAN tag is still present on the egress interface. - Positive: apply pop_vlan, verify the tag is removed and an untagged ICMP echo request arrives at the egress interface. Static ARP entries avoid the complexity of VLAN-tagged ARP resolution (the egress side has no VLAN sub-interface and cannot process tagged ARP). Signed-off-by: Minxi Hou <[email protected]> --- v1 -> v2: rebase to latest net-next/main, drop --base=auto .../selftests/net/openvswitch/openvswitch.sh | 132 ++++++++++++++++++ 1 file changed, 132 insertions(+) diff --git a/tools/testing/selftests/net/openvswitch/openvswitch.sh b/tools/testing/selftests/net/openvswitch/openvswitch.sh index b327d3061ed5..cd614ff7b740 100755 --- a/tools/testing/selftests/net/openvswitch/openvswitch.sh +++ b/tools/testing/selftests/net/openvswitch/openvswitch.sh @@ -27,6 +27,7 @@ tests=" upcall_interfaces ovs: test the upcall interfaces tunnel_metadata ovs: test extraction of tunnel metadata drop_reason drop: test drop reasons are emitted + pop_vlan vlan-pop: POP_VLAN action strips 802.1Q tag psample psample: Sampling packets with psample" info() { @@ -830,6 +831,137 @@ test_tunnel_metadata() { return 0 } +test_pop_vlan() { + modprobe -q openvswitch 2>/dev/null || true + [ -d /sys/module/openvswitch ] || return $ksft_skip + ip netns add __test_pop_vlan_netns__ 2>/dev/null || \ + { info "CONFIG_NET_NS missing"; return $ksft_skip; } + ip netns del __test_pop_vlan_netns__ 2>/dev/null + modprobe -q 8021q 2>/dev/null || true + [ -d /sys/module/8021q ] || { info "CONFIG_VLAN_8021Q missing"; return $ksft_skip; } + + local sbx="test_pop_vlan" + sbx_add "$sbx" || return $ksft_skip + ovs_add_dp "$sbx" vlandp || return 1 + + # --- baseline: untagged forwarding --- + ovs_add_netns_and_veths "$sbx" vlandp ns1 veth1 ns1veth 192.0.2.1/24 || return 1 + ovs_add_netns_and_veths "$sbx" vlandp ns2 veth2 ns2veth 192.0.2.2/24 || return 1 + + # ARP + IPv4 bidirectional (all untagged) + ovs_add_flow "$sbx" vlandp \ + 'in_port(1),eth(),eth_type(0x0806),arp()' '2' || return 1 + ovs_add_flow "$sbx" vlandp \ + 'in_port(2),eth(),eth_type(0x0806),arp()' '1' || return 1 + ovs_add_flow "$sbx" vlandp \ + 'in_port(1),eth(),eth_type(0x0800),ipv4()' '2' || return 1 + ovs_add_flow "$sbx" vlandp \ + 'in_port(2),eth(),eth_type(0x0800),ipv4()' '1' || return 1 + ip netns exec ns1 ping -c 3 -W 2 192.0.2.2 || return 1 + + # --- POP_VLAN test --- + # Register cleanup before creating resources (safe on failure paths) + on_exit "ip -n ns1 link del ns1veth.10 2>/dev/null || true + ip -n ns2 addr del 198.51.100.2/24 dev ns2veth 2>/dev/null || true" + + # ns1: VLAN sub-interface generates tagged frames + ip -n ns1 link add link ns1veth name ns1veth.10 type vlan id 10 + ip -n ns1 addr add 198.51.100.1/24 dev ns1veth.10 + ip -n ns1 link set ns1veth.10 up + + # ns2: no VLAN sub-interface. POP delivers untagged frames to ns2veth + ip -n ns2 addr add 198.51.100.2/24 dev ns2veth + + # veth disable VLAN offload + GRO (ensure kernel software tag processing) + if command -v ethtool >/dev/null 2>&1; then + ip netns exec ns1 ethtool -k ns1veth 2>/dev/null | grep -q vlan-offload && \ + ip netns exec ns1 ethtool -K ns1veth rx-vlan-offload off \ + tx-vlan-offload off gro off 2>/dev/null || true + ip netns exec ns2 ethtool -k ns2veth 2>/dev/null | grep -q vlan-offload && \ + ip netns exec ns2 ethtool -K ns2veth rx-vlan-offload off \ + tx-vlan-offload off gro off 2>/dev/null || true + fi + + ovs_del_flows "$sbx" vlandp + + # Static ARP avoids VLAN-tagged ARP complexity (ns2 has no VLAN + # sub-interface, so tagged ARP would be invisible to ns2). + local ns1veth10mac ns2mac + ns1veth10mac=$(ip -n ns1 link show ns1veth.10 | \ + awk '/link\/ether/ {print $2}') + ns2mac=$(ip -n ns2 link show ns2veth | \ + awk '/link\/ether/ {print $2}') + [ -n "$ns1veth10mac" ] && echo "$ns1veth10mac" | \ + grep -qE "^([0-9a-fA-F]{2}:){5}[0-9a-fA-F]{2}$" || return 1 + [ -n "$ns2mac" ] && echo "$ns2mac" | \ + grep -qE "^([0-9a-fA-F]{2}:){5}[0-9a-fA-F]{2}$" || return 1 + ip -n ns1 neigh replace 198.51.100.2 lladdr "$ns2mac" \ + dev ns1veth.10 nud permanent || return 1 + ip -n ns2 neigh replace 198.51.100.1 lladdr "$ns1veth10mac" \ + dev ns2veth nud permanent || return 1 + + # --- Negative check: fwd without pop_vlan, VLAN tag stays --- + ovs_add_flow "$sbx" vlandp \ + 'in_port(1),eth(),eth_type(0x8100),vlan(vid=10),encap(eth_type(0x0800),ipv4(src=198.51.100.1,proto=1),icmp())' \ + '2' || return 1 + + local pcap_no_pop + pcap_no_pop=$(mktemp --suffix=.pcap) + on_exit "rm -f $pcap_no_pop" + ip netns exec ns2 tcpdump -nei ns2veth -w "$pcap_no_pop" -U & + local tpid_no_pop=$! + on_exit "kill $tpid_no_pop 2>/dev/null || true" + sleep $((WAIT_TIMEOUT / 5 < 2 ? 2 : WAIT_TIMEOUT / 5)) + + ip netns exec ns1 ping -I ns1veth.10 -c 3 -W 1 198.51.100.2 \ + >/dev/null 2>&1 || true + kill $tpid_no_pop 2>/dev/null || true; wait $tpid_no_pop 2>/dev/null || true + + # assert: VLAN tag still present (no pop_vlan in action) + tcpdump -nr "$pcap_no_pop" 'vlan' 2>/dev/null | grep -q . || { + info "FAIL: negative check: no VLAN tag (expected tag present)"; return 1 + } + + ovs_del_flows "$sbx" vlandp + + # --- Positive: pop_vlan strips tag --- + ovs_add_flow "$sbx" vlandp \ + 'in_port(1),eth(),eth_type(0x8100),vlan(vid=10),encap(eth_type(0x0800),ipv4(src=198.51.100.1,proto=1),icmp())' \ + 'pop_vlan,2' || return 1 + ovs_add_flow "$sbx" vlandp \ + 'in_port(2),eth(),eth_type(0x0800),ipv4()' '1' || return 1 + + local pcap + pcap=$(mktemp --suffix=.pcap) + on_exit "rm -f $pcap" + ip netns exec ns2 tcpdump -nei ns2veth -w "$pcap" -U & + local tpid=$! + on_exit "kill $tpid 2>/dev/null || true" + sleep $((WAIT_TIMEOUT / 5 < 2 ? 2 : WAIT_TIMEOUT / 5)) + + # ping reply unreachable: ns1veth.10 only accepts tagged frames, + # ns2 sends untagged reply -> dropped by ns1veth.10. + local ping_rc=0 + ip netns exec ns1 ping -I ns1veth.10 -c 3 -W 1 198.51.100.2 \ + >/dev/null 2>&1 || ping_rc=$? + kill $tpid 2>/dev/null || true; wait $tpid 2>/dev/null || true + + # ping failure is expected (reply path asymmetric) + [ "$ping_rc" -ne 0 ] || \ + info "NOTE: ping succeeded unexpectedly (reply reached ns1veth.10)" + + # assert: no VLAN tag (POP succeeded), untagged ICMP echo request arrived + tcpdump -nr "$pcap" 'vlan' 2>/dev/null | grep -q . && { + info "FAIL: POP_VLAN: VLAN tag still present"; return 1 + } + tcpdump -nr "$pcap" 'icmp and icmp[icmptype]=8' \ + 2>/dev/null | grep -q . || { + info "FAIL: POP_VLAN: no untagged ICMP echo request"; return 1 + } + + return 0 +} + run_test() { ( tname="$1" -- 2.53.0
