#!/bin/bash # SPDX-License-Identifier: GPL-2.0 # # This test installs a TC bpf program that throttles a TCP flow # with dst port = 9000 down to 5MBps. Then it measures actual # throughput of the flow. if [[ $EUID -ne 0 ]]; then echo "This script must be run as root" echo "FAIL" exit 1 fi # check that nc, dd, and timeout are present command -v nc >/dev/null 2>&1 || \ { echo >&2 "nc is not available"; exit 1; } command -v dd >/dev/null 2>&1 || \ { echo >&2 "nc is not available"; exit 1; } command -v timeout >/dev/null 2>&1 || \ { echo >&2 "timeout is not available"; exit 1; } readonly NS_SRC="ns-src-$(mktemp -u XXXXXX)" readonly NS_DST="ns-dst-$(mktemp -u XXXXXX)" readonly IP_SRC="172.16.1.100" readonly IP_DST="172.16.2.100" cleanup() { ip netns del ${NS_SRC} ip netns del ${NS_DST} } trap cleanup EXIT set -e # exit on error ip netns add "${NS_SRC}" ip netns add "${NS_DST}" ip link add veth_src type veth peer name veth_dst ip link set veth_src netns ${NS_SRC} ip link set veth_dst netns ${NS_DST} ip -netns ${NS_SRC} addr add ${IP_SRC}/24 dev veth_src ip -netns ${NS_DST} addr add ${IP_DST}/24 dev veth_dst ip -netns ${NS_SRC} link set dev veth_src up ip -netns ${NS_DST} link set dev veth_dst up ip -netns ${NS_SRC} route add ${IP_DST}/32 dev veth_src ip -netns ${NS_DST} route add ${IP_SRC}/32 dev veth_dst # set up TC on TX ip netns exec ${NS_SRC} tc qdisc add dev veth_src root fq ip netns exec ${NS_SRC} tc qdisc add dev veth_src clsact ip netns exec ${NS_SRC} tc filter add dev veth_src egress \ bpf da obj test_tc_edt.o sec cls_test # start the listener ip netns exec ${NS_DST} bash -c \ "nc -4 -l -s ${IP_DST} -p 9000 >/dev/null &" declare -i NC_PID=$! sleep 1 declare -ir TIMEOUT=20 declare -ir EXPECTED_BPS=5000000 # run the load, capture RX bytes on DST declare -ir RX_BYTES_START=$( ip netns exec ${NS_DST} \ cat /sys/class/net/veth_dst/statistics/rx_bytes ) set +e ip netns exec ${NS_SRC} bash -c "timeout ${TIMEOUT} dd if=/dev/zero \ bs=1000 count=1000000 > /dev/tcp/${IP_DST}/9000 2>/dev/null" set -e declare -ir RX_BYTES_END=$( ip netns exec ${NS_DST} \ cat /sys/class/net/veth_dst/statistics/rx_bytes ) declare -ir ACTUAL_BPS=$(( ($RX_BYTES_END - $RX_BYTES_START) / $TIMEOUT )) echo $TIMEOUT $ACTUAL_BPS $EXPECTED_BPS | \ awk '{printf "elapsed: %d sec; bps difference: %.2f%%\n", $1, ($2-$3)*100.0/$3}' # Pass the test if the actual bps is within 1% of the expected bps. # The difference is usually about 0.1% on a 20-sec test, and ==> zero # the longer the test runs. declare -ir RES=$( echo $ACTUAL_BPS $EXPECTED_BPS | \ awk 'function abs(x){return ((x < 0.0) ? -x : x)} {if (abs(($1-$2)*100.0/$2) > 1.0) { print "1" } else { print "0"} }' ) if [ "${RES}" == "0" ] ; then echo "PASS" else echo "FAIL" exit 1 fi