Subject: Re: [PATCH bpf-next 7/7] selftests/bpf: introduce XDP compliance test tool

From: Martin KaFai Lau <[email-masked]>
Date: Mon, 23 Jan 2023 22:34:36 -0800

On 1/20/23 9:16 AM, Lorenzo Bianconi wrote:
> +static __always_inline int xdp_process_echo_packet(struct xdp_md *xdp, bool dut)
> +{
> +	void *data_end = (void *)(long)xdp->data_end;
> +	__be32 saddr = dut ? tester_ip : dut_ip;
> +	__be32 daddr = dut ? dut_ip : tester_ip;
> +	void *data = (void *)(long)xdp->data;
> +	struct ethhdr *eh = data;
> +	struct tlv_hdr *tlv;
> +	struct udphdr *uh;
> +	struct iphdr *ih;
> +	__be16 port;
> +	__u8 *cmd;
> +
> +	if (eh + 1 > (struct ethhdr *)data_end)
> +		return -EINVAL;
> +
> +	if (eh->h_proto != bpf_htons(ETH_P_IP))
> +		return -EINVAL;

Both v6 and v4 support are needed as a tool.

[ ... ]

> diff --git a/tools/testing/selftests/bpf/test_xdp_features.sh b/tools/testing/selftests/bpf/test_xdp_features.sh
> new file mode 100755
> index 000000000000..98b8fd2b6c16
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/test_xdp_features.sh
> @@ -0,0 +1,99 @@
> +#!/bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +
> +# Create 2 namespaces with two veth peers, and
> +# check reported and detected XDP capabilities
> +#
> +#   NS0(v00)              NS1(v11)
> +#       |                     |
> +#       |                     |
> +# (v01, id:111)  ------  (v10,id:222)
> +
> +readonly NS0="ns1-$(mktemp -u XXXXXX)"
> +readonly NS1="ns2-$(mktemp -u XXXXXX)"
> +ret=1
> +
> +setup() {
> +	{
> +		ip netns add ${NS0}
> +		ip netns add ${NS1}
> +
> +		ip link add v01 index 111 type veth peer name v00 netns ${NS0}
> +		ip link add v10 index 222 type veth peer name v11 netns ${NS1}
> +
> +		ip link set v01 up
> +		ip addr add 10.10.0.1/24 dev v01
> +		ip link set v01 address 00:11:22:33:44:55
> +		ip -n ${NS0} link set dev v00 up
> +		ip -n ${NS0} addr add 10.10.0.11/24 dev v00
> +		ip -n ${NS0} route add default via 10.10.0.1
> +		ip -n ${NS0} link set v00 address 00:12:22:33:44:55
> +
> +		ip link set v10 up
> +		ip addr add 10.10.1.1/24 dev v10
> +		ip link set v10 address 00:13:22:33:44:55
> +		ip -n ${NS1} link set dev v11 up
> +		ip -n ${NS1} addr add 10.10.1.11/24 dev v11
> +		ip -n ${NS1} route add default via 10.10.1.1
> +		ip -n ${NS1} link set v11 address 00:14:22:33:44:55
> +
> +		sysctl -w net.ipv4.ip_forward=1
> +		# Enable XDP mode
> +		ethtool -K v01 gro on
> +		ethtool -K v01 tx-checksumming off
> +		ip netns exec ${NS0} ethtool -K v00 gro on
> +		ip netns exec ${NS0} ethtool -K v00 tx-checksumming off
> +		ethtool -K v10 gro on
> +		ethtool -K v10 tx-checksumming off
> +		ip netns exec ${NS1} ethtool -K v11 gro on
> +		ip netns exec ${NS1} ethtool -K v11 tx-checksumming off
> +	} > /dev/null 2>&1
> +}
> +
> +cleanup() {
> +	ip link del v01 2> /dev/null
> +	ip link del v10 2> /dev/null
> +	ip netns del ${NS0} 2> /dev/null
> +	ip netns del ${NS1} 2> /dev/null
> +	[ "$(pidof xdp_features)" = "" ] || kill $(pidof xdp_features) 2> /dev/null
> +}
> +
> +test_xdp_features() {
> +	setup
> +
> +	## XDP_PASS
> +	ip netns exec ${NS1} ./xdp_features -f XDP_PASS -D 10.10.1.11 -T 10.10.0.11 v11 &
> +	ip netns exec ${NS0} ./xdp_features -t -f XDP_PASS -D 10.10.1.11 -C 10.10.1.11 -T 10.10.0.11 v00
> +
> +	[ $? -ne 0 ] && exit
> +
> +	# XDP_DROP
> +	ip netns exec ${NS1} ./xdp_features -f XDP_DROP -D 10.10.1.11 -T 10.10.0.11 v11 &
> +	ip netns exec ${NS0} ./xdp_features -t -f XDP_DROP -D 10.10.1.11 -C 10.10.1.11 -T 10.10.0.11 v00
> +
> +	[ $? -ne 0 ] && exit
> +
> +	## XDP_TX
> +	./xdp_features -f XDP_TX -D 10.10.0.1 -T 10.10.0.11 v01 &
> +	ip netns exec ${NS0} ./xdp_features -t -f XDP_TX -D 10.10.0.1 -C 10.10.0.1 -T 10.10.0.11 v00
> +
> +	## XDP_REDIRECT
> +	ip netns exec ${NS1} ./xdp_features -f XDP_REDIRECT -D 10.10.1.11 -T 10.10.0.11 v11 &
> +	ip netns exec ${NS0} ./xdp_features -t -f XDP_REDIRECT -D 10.10.1.11 -C 10.10.1.11 -T 10.10.0.11 v00
> +
> +	[ $? -ne 0 ] && exit
> +
> +	## XDP_NDO_XMIT
> +	./xdp_features -f XDP_NDO_XMIT -D 10.10.0.1 -T 10.10.0.11 v01 &
> +	ip netns exec ${NS0} ./xdp_features -t -f XDP_NDO_XMIT -D 10.10.0.1 -C 10.10.0.1 -T 10.10.0.11 v00
> +
> +	ret=$?
> +	cleanup
> +}
> +
> +set -e
> +trap cleanup 2 3 6 9
> +
> +test_xdp_features

This won't be run by bpf CI.

A selftest in test_progs is needed to test the libbpf changes in patch 6.