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Diffstat (limited to 'tools/testing/selftests/net/fou_mcast_encap.sh')
| -rwxr-xr-x | tools/testing/selftests/net/fou_mcast_encap.sh | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/tools/testing/selftests/net/fou_mcast_encap.sh b/tools/testing/selftests/net/fou_mcast_encap.sh new file mode 100755 index 000000000000..70210d39fba3 --- /dev/null +++ b/tools/testing/selftests/net/fou_mcast_encap.sh @@ -0,0 +1,172 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# +# Test that UDP encapsulation (FOU) correctly handles packet resubmit +# when packets are delivered via the multicast UDP delivery path. +# +# When a FOU-encapsulated packet arrives with a multicast destination IP, +# __udp4_lib_mcast_deliver() / __udp6_lib_mcast_deliver() must resubmit +# it to the inner protocol handler (e.g., GRE) rather than consuming it. +# This test verifies both IPv4 and IPv6 paths by creating a FOU/GRETAP +# tunnel with a multicast remote address and sending ping through it. +# +# The early demux optimization can mask this issue by routing packets via +# the unicast path (udp[6]_unicast_rcv_skb), so we disable it to force +# packets through the multicast delivery function. + +source lib.sh + +NSENDER="" +NRECV="" + +FOU_PORT4=4797 +FOU_PORT6=4798 +MCAST4=239.0.0.1 +MCAST6=ff0e::1 + +TUN4_S=192.168.99.1 +TUN4_R=192.168.99.2 +TUN6_S=2001:db8:99::1 +TUN6_R=2001:db8:99::2 + +cleanup() { + cleanup_all_ns +} + +trap cleanup EXIT + +setup_common() { + setup_ns NSENDER NRECV + + # Create veth pair directly inside namespaces to avoid name + # collisions with devices in the root namespace. + ip link add veth_s netns "$NSENDER" type veth \ + peer name veth_r netns "$NRECV" + + ip -n "$NSENDER" link set veth_s up + ip -n "$NRECV" link set veth_r up + + # Same sysctl controls early demux for both IPv4 and IPv6. + ip netns exec "$NRECV" sysctl -wq net.ipv4.ip_early_demux=0 +} + +setup_ipv4() { + # IPv4 FOU (CONFIG_NET_FOU) is built in on kernels configured for + # these tests, so no module load is needed here. + ip -n "$NSENDER" addr add 10.0.0.1/24 dev veth_s + ip -n "$NRECV" addr add 10.0.0.2/24 dev veth_r + + # Join multicast group on receiver + ip -n "$NRECV" addr add "$MCAST4/32" dev veth_r autojoin + + ip -n "$NSENDER" route add 239.0.0.0/8 dev veth_s + ip -n "$NRECV" route add 239.0.0.0/8 dev veth_r + + # Sender: GRETAP with FOU encap (no FOU listener needed on TX side) + ip -n "$NSENDER" link add eoudp4 type gretap \ + remote "$MCAST4" local 10.0.0.1 \ + encap fou encap-sport "$FOU_PORT4" encap-dport "$FOU_PORT4" \ + key "$MCAST4" + ip -n "$NSENDER" link set eoudp4 up + ip -n "$NSENDER" addr add "$TUN4_S/24" dev eoudp4 + + # Receiver: FOU listener + GRETAP + ip netns exec "$NRECV" ip fou add port "$FOU_PORT4" ipproto 47 + ip -n "$NRECV" link add eoudp4 type gretap \ + remote "$MCAST4" local 10.0.0.2 \ + encap fou encap-sport "$FOU_PORT4" encap-dport "$FOU_PORT4" \ + key "$MCAST4" + ip -n "$NRECV" link set eoudp4 up + ip -n "$NRECV" addr add "$TUN4_R/24" dev eoudp4 + + # Static neigh on sender: ARP replies cannot traverse the + # unidirectional multicast tunnel. + local recv_mac + recv_mac=$(ip -n "$NRECV" link show eoudp4 | awk '/ether/{print $2}') + ip -n "$NSENDER" neigh add "$TUN4_R" lladdr "$recv_mac" dev eoudp4 +} + +setup_ipv6() { + # Skip cleanly if IPv6 or the fou6 module is not available. + [ -e /proc/sys/net/ipv6 ] || return "$ksft_skip" + modprobe -q fou6 || return "$ksft_skip" + + ip -n "$NSENDER" addr add 2001:db8::1/64 dev veth_s nodad + ip -n "$NRECV" addr add 2001:db8::2/64 dev veth_r nodad + + # Join multicast group on receiver + ip -n "$NRECV" addr add "$MCAST6/128" dev veth_r autojoin + + ip -n "$NSENDER" -6 route add ff00::/8 dev veth_s + ip -n "$NRECV" -6 route add ff00::/8 dev veth_r + + # Sender: ip6gretap with FOU encap + ip -n "$NSENDER" link add eoudp6 type ip6gretap \ + remote "$MCAST6" local 2001:db8::1 \ + encap fou encap-sport "$FOU_PORT6" encap-dport "$FOU_PORT6" \ + key 42 + ip -n "$NSENDER" link set eoudp6 up + ip -n "$NSENDER" addr add "$TUN6_S/64" dev eoudp6 nodad + + # Receiver: FOU listener (IPv6) + ip6gretap + ip netns exec "$NRECV" ip fou add port "$FOU_PORT6" ipproto 47 -6 + ip -n "$NRECV" link add eoudp6 type ip6gretap \ + remote "$MCAST6" local 2001:db8::2 \ + encap fou encap-sport "$FOU_PORT6" encap-dport "$FOU_PORT6" \ + key 42 + ip -n "$NRECV" link set eoudp6 up + ip -n "$NRECV" addr add "$TUN6_R/64" dev eoudp6 nodad + + # Static neigh on sender: neighbor discovery cannot traverse the + # unidirectional multicast tunnel. + local recv_mac + recv_mac=$(ip -n "$NRECV" link show eoudp6 | awk '/ether/{print $2}') + ip -n "$NSENDER" neigh add "$TUN6_R" lladdr "$recv_mac" dev eoudp6 +} + +get_rx_packets() { + local dev="$1" + + ip -n "$NRECV" -s link show "$dev" | awk '/RX:/{getline; print $2}' +} + +run_ping_test() { + local family="$1" + local dev="$2" + local dst="$3" + local name="$4" + local count=100 + local rx_before rx_after rx_delta + + # Warmup: let any initial broadcast/ND traffic settle + ip netns exec "$NSENDER" ping "$family" -c 1 -W 1 "$dst" \ + >/dev/null 2>&1 + sleep 1 + + rx_before=$(get_rx_packets "$dev") + ip netns exec "$NSENDER" ping "$family" -i 0.01 -c $count -W 1 "$dst" \ + >/dev/null 2>&1 + sleep 1 + rx_after=$(get_rx_packets "$dev") + + rx_delta=$((rx_after - rx_before)) + + if [ "$rx_delta" -ge "$count" ]; then + RET=$ksft_pass + else + RET=$ksft_fail + fi + log_test "$name (received $rx_delta/$count)" +} + +setup_common +setup_ipv4 +run_ping_test -4 eoudp4 "$TUN4_R" "FOU/GRETAP IPv4 multicast encap resubmit" + +if setup_ipv6; then + run_ping_test -6 eoudp6 "$TUN6_R" "FOU/ip6gretap IPv6 multicast encap resubmit" +else + log_test_skip "FOU/ip6gretap IPv6 multicast encap resubmit" +fi + +exit "$EXIT_STATUS" |