tools/testing/selftests/net/mptcp/mptcp_lib.sh - linux - Git at Google

 #! /bin/bash
 # SPDX-License-Identifier: GPL-2.0

 . "$(dirname "${0}")/../lib.sh"
 . "$(dirname "${0}")/../net_helper.sh"

 readonly KSFT_PASS=0
 readonly KSFT_FAIL=1
 readonly KSFT_SKIP=4

 # shellcheck disable=SC2155 # declare and assign separately
 readonly KSFT_TEST="${MPTCP_LIB_KSFT_TEST:-$(basename "${0}" .sh)}"

 # These variables are used in some selftests, read-only
 declare -rx MPTCP_LIB_EVENT_CREATED=1           # MPTCP_EVENT_CREATED
 declare -rx MPTCP_LIB_EVENT_ESTABLISHED=2       # MPTCP_EVENT_ESTABLISHED
 declare -rx MPTCP_LIB_EVENT_CLOSED=3            # MPTCP_EVENT_CLOSED
 declare -rx MPTCP_LIB_EVENT_ANNOUNCED=6         # MPTCP_EVENT_ANNOUNCED
 declare -rx MPTCP_LIB_EVENT_REMOVED=7           # MPTCP_EVENT_REMOVED
 declare -rx MPTCP_LIB_EVENT_SUB_ESTABLISHED=10  # MPTCP_EVENT_SUB_ESTABLISHED
 declare -rx MPTCP_LIB_EVENT_SUB_CLOSED=11       # MPTCP_EVENT_SUB_CLOSED
 declare -rx MPTCP_LIB_EVENT_SUB_PRIORITY=13     # MPTCP_EVENT_SUB_PRIORITY
 declare -rx MPTCP_LIB_EVENT_LISTENER_CREATED=15 # MPTCP_EVENT_LISTENER_CREATED
 declare -rx MPTCP_LIB_EVENT_LISTENER_CLOSED=16  # MPTCP_EVENT_LISTENER_CLOSED

 declare -rx MPTCP_LIB_AF_INET=2
 declare -rx MPTCP_LIB_AF_INET6=10

 MPTCP_LIB_SUBTESTS=()
 MPTCP_LIB_SUBTESTS_DUPLICATED=0
 MPTCP_LIB_SUBTEST_FLAKY=0
 MPTCP_LIB_SUBTESTS_LAST_TS_MS=
 MPTCP_LIB_TEST_COUNTER=0
 MPTCP_LIB_TEST_FORMAT="%02u %-50s"
 MPTCP_LIB_IP_MPTCP=0

 # only if supported (or forced) and not disabled, see no-color.org
 if { [ -t 1 ] || [ "${SELFTESTS_MPTCP_LIB_COLOR_FORCE:-}" = "1" ]; } &&
    [ "${NO_COLOR:-}" != "1" ]; then
 	readonly MPTCP_LIB_COLOR_RED="\E[1;31m"
 	readonly MPTCP_LIB_COLOR_GREEN="\E[1;32m"
 	readonly MPTCP_LIB_COLOR_YELLOW="\E[1;33m"
 	readonly MPTCP_LIB_COLOR_BLUE="\E[1;34m"
 	readonly MPTCP_LIB_COLOR_RESET="\E[0m"
 else
 	readonly MPTCP_LIB_COLOR_RED=
 	readonly MPTCP_LIB_COLOR_GREEN=
 	readonly MPTCP_LIB_COLOR_YELLOW=
 	readonly MPTCP_LIB_COLOR_BLUE=
 	readonly MPTCP_LIB_COLOR_RESET=
 fi

 # SELFTESTS_MPTCP_LIB_OVERRIDE_FLAKY env var can be set not to ignore errors
 # from subtests marked as flaky
 mptcp_lib_override_flaky() {
 	[ "${SELFTESTS_MPTCP_LIB_OVERRIDE_FLAKY:-}" = 1 ]
 }

 mptcp_lib_subtest_is_flaky() {
 	[ "${MPTCP_LIB_SUBTEST_FLAKY}" = 1 ] && ! mptcp_lib_override_flaky
 }

 # $1: color, $2: text
 mptcp_lib_print_color() {
 	echo -e "${MPTCP_LIB_START_PRINT:-}${*}${MPTCP_LIB_COLOR_RESET}"
 }

 mptcp_lib_print_ok() {
 	mptcp_lib_print_color "${MPTCP_LIB_COLOR_GREEN}${*}"
 }

 mptcp_lib_print_warn() {
 	mptcp_lib_print_color "${MPTCP_LIB_COLOR_YELLOW}${*}"
 }

 mptcp_lib_print_info() {
 	mptcp_lib_print_color "${MPTCP_LIB_COLOR_BLUE}${*}"
 }

 mptcp_lib_print_err() {
 	mptcp_lib_print_color "${MPTCP_LIB_COLOR_RED}${*}"
 }

 # shellcheck disable=SC2120 # parameters are optional
 mptcp_lib_pr_ok() {
 	mptcp_lib_print_ok "[ OK ]${1:+ ${*}}"
 }

 mptcp_lib_pr_skip() {
 	mptcp_lib_print_warn "[SKIP]${1:+ ${*}}"
 }

 mptcp_lib_pr_fail() {
 	local title cmt

 	if mptcp_lib_subtest_is_flaky; then
 		title="IGNO"
 		cmt=" (flaky)"
 	else
 		title="FAIL"
 	fi

 	mptcp_lib_print_err "[${title}]${cmt}${1:+ ${*}}"
 }

 mptcp_lib_pr_info() {
 	mptcp_lib_print_info "INFO: ${*}"
 }

 # SELFTESTS_MPTCP_LIB_EXPECT_ALL_FEATURES env var can be set when validating all
 # features using the last version of the kernel and the selftests to make sure
 # a test is not being skipped by mistake.
 mptcp_lib_expect_all_features() {
 	[ "${SELFTESTS_MPTCP_LIB_EXPECT_ALL_FEATURES:-}" = "1" ]
 }

 # $1: msg
 mptcp_lib_fail_if_expected_feature() {
 	if mptcp_lib_expect_all_features; then
 		echo "ERROR: missing feature: ${*}"
 		exit ${KSFT_FAIL}
 	fi

 	return 1
 }

 # $1: file
 mptcp_lib_has_file() {
 	local f="${1}"

 	if [ -f "${f}" ]; then
 		return 0
 	fi

 	mptcp_lib_fail_if_expected_feature "${f} file not found"
 }

 mptcp_lib_check_mptcp() {
 	if ! mptcp_lib_has_file "/proc/sys/net/mptcp/enabled"; then
 		mptcp_lib_pr_skip "MPTCP support is not available"
 		exit ${KSFT_SKIP}
 	fi
 }

 mptcp_lib_check_kallsyms() {
 	if ! mptcp_lib_has_file "/proc/kallsyms"; then
 		mptcp_lib_pr_skip "CONFIG_KALLSYMS is missing"
 		exit ${KSFT_SKIP}
 	fi
 }

 # Internal: use mptcp_lib_kallsyms_has() instead
 __mptcp_lib_kallsyms_has() {
 	local sym="${1}"

 	mptcp_lib_check_kallsyms

 	grep -q " ${sym}" /proc/kallsyms
 }

 # $1: part of a symbol to look at, add '$' at the end for full name
 mptcp_lib_kallsyms_has() {
 	local sym="${1}"

 	if __mptcp_lib_kallsyms_has "${sym}"; then
 		return 0
 	fi

 	mptcp_lib_fail_if_expected_feature "${sym} symbol not found"
 }

 # $1: part of a symbol to look at, add '$' at the end for full name
 mptcp_lib_kallsyms_doesnt_have() {
 	local sym="${1}"

 	if ! __mptcp_lib_kallsyms_has "${sym}"; then
 		return 0
 	fi

 	mptcp_lib_fail_if_expected_feature "${sym} symbol has been found"
 }

 # !!!AVOID USING THIS!!!
 # Features might not land in the expected version and features can be backported
 #
 # $1: kernel version, e.g. 6.3
 mptcp_lib_kversion_ge() {
 	local exp_maj="${1%.*}"
 	local exp_min="${1#*.}"
 	local v maj min

 	# If the kernel has backported features, set this env var to 1:
 	if [ "${SELFTESTS_MPTCP_LIB_NO_KVERSION_CHECK:-}" = "1" ]; then
 		return 0
 	fi

 	v=$(uname -r | cut -d'.' -f1,2)
 	maj=${v%.*}
 	min=${v#*.}

 	if   [ "${maj}" -gt "${exp_maj}" ] ||
 	   { [ "${maj}" -eq "${exp_maj}" ] && [ "${min}" -ge "${exp_min}" ]; }; then
 		return 0
 	fi

 	mptcp_lib_fail_if_expected_feature "kernel version ${1} lower than ${v}"
 }

 mptcp_lib_subtests_last_ts_reset() {
 	MPTCP_LIB_SUBTESTS_LAST_TS_MS="$(date +%s%3N)"
 }
 mptcp_lib_subtests_last_ts_reset

 __mptcp_lib_result_check_duplicated() {
 	local subtest

 	for subtest in "${MPTCP_LIB_SUBTESTS[@]}"; do
 		if [[ "${subtest}" == *" - ${KSFT_TEST}: ${*%% #*}" ]]; then
 			MPTCP_LIB_SUBTESTS_DUPLICATED=1
 			mptcp_lib_print_err "Duplicated entry: ${*}"
 			break
 		fi
 	done
 }

 __mptcp_lib_result_add() {
 	local result="${1}"
 	local time="time="
 	local ts_prev_ms
 	shift

 	local id=$((${#MPTCP_LIB_SUBTESTS[@]} + 1))

 	__mptcp_lib_result_check_duplicated "${*}"

 	# not to add two '#'
 	[[ "${*}" != *"#"* ]] && time="# ${time}"

 	ts_prev_ms="${MPTCP_LIB_SUBTESTS_LAST_TS_MS}"
 	mptcp_lib_subtests_last_ts_reset
 	time+="$((MPTCP_LIB_SUBTESTS_LAST_TS_MS - ts_prev_ms))ms"

 	MPTCP_LIB_SUBTESTS+=("${result} ${id} - ${KSFT_TEST}: ${*} ${time}")
 }

 # $1: test name
 mptcp_lib_result_pass() {
 	__mptcp_lib_result_add "ok" "${1}"
 }

 # $1: test name
 mptcp_lib_result_fail() {
 	if mptcp_lib_subtest_is_flaky; then
 		# It might sound better to use 'not ok # TODO' or 'ok # SKIP',
 		# but some CIs don't understand 'TODO' and treat SKIP as errors.
 		__mptcp_lib_result_add "ok" "${1} # IGNORE Flaky"
 	else
 		__mptcp_lib_result_add "not ok" "${1}"
 	fi
 }

 # $1: test name
 mptcp_lib_result_skip() {
 	__mptcp_lib_result_add "ok" "${1} # SKIP"
 }

 # $1: result code ; $2: test name
 mptcp_lib_result_code() {
 	local ret="${1}"
 	local name="${2}"

 	case "${ret}" in
 		"${KSFT_PASS}")
 			mptcp_lib_result_pass "${name}"
 			;;
 		"${KSFT_FAIL}")
 			mptcp_lib_result_fail "${name}"
 			;;
 		"${KSFT_SKIP}")
 			mptcp_lib_result_skip "${name}"
 			;;
 		*)
 			echo "ERROR: wrong result code: ${ret}"
 			exit ${KSFT_FAIL}
 			;;
 	esac
 }

 mptcp_lib_result_print_all_tap() {
 	local subtest

 	if [ ${#MPTCP_LIB_SUBTESTS[@]} -eq 0 ] ||
 	   [ "${SELFTESTS_MPTCP_LIB_NO_TAP:-}" = "1" ]; then
 		return
 	fi

 	printf "\nTAP version 13\n"
 	printf "1..%d\n" "${#MPTCP_LIB_SUBTESTS[@]}"

 	for subtest in "${MPTCP_LIB_SUBTESTS[@]}"; do
 		printf "%s\n" "${subtest}"
 	done

 	if [ "${MPTCP_LIB_SUBTESTS_DUPLICATED}" = 1 ] &&
 	   mptcp_lib_expect_all_features; then
 		mptcp_lib_print_err "Duplicated test entries"
 		exit ${KSFT_FAIL}
 	fi
 }

 # get the value of keyword $1 in the line marked by keyword $2
 mptcp_lib_get_info_value() {
 	grep "${2}" | sed -n 's/.*\('"${1}"':\)\([0-9a-f:.]*\).*$/\2/p;q'
 }

 # $1: info name ; $2: evts_ns ; [$3: event type; [$4: addr]]
 mptcp_lib_evts_get_info() {
 	grep "${4:-}" "${2}" | mptcp_lib_get_info_value "${1}" "^type:${3:-1},"
 }

 # $1: PID
 mptcp_lib_kill_wait() {
 	[ "${1}" -eq 0 ] && return 0

 	kill -SIGUSR1 "${1}" > /dev/null 2>&1
 	kill "${1}" > /dev/null 2>&1
 	wait "${1}" 2>/dev/null
 }

 # $1: IP address
 mptcp_lib_is_v6() {
 	[ -z "${1##*:*}" ]
 }

 # $1: ns, $2: MIB counter
 mptcp_lib_get_counter() {
 	local ns="${1}"
 	local counter="${2}"
 	local count

 	count=$(ip netns exec "${ns}" nstat -asz "${counter}" |
 		awk 'NR==1 {next} {print $2}')
 	if [ -z "${count}" ]; then
 		mptcp_lib_fail_if_expected_feature "${counter} counter"
 		return 1
 	fi

 	echo "${count}"
 }

 mptcp_lib_make_file() {
 	local name="${1}"
 	local bs="${2}"
 	local size="${3}"

 	dd if=/dev/urandom of="${name}" bs="${bs}" count="${size}" 2> /dev/null
 	echo -e "\nMPTCP_TEST_FILE_END_MARKER" >> "${name}"
 }

 # $1: file
 mptcp_lib_print_file_err() {
 	ls -l "${1}" 1>&2
 	echo "Trailing bytes are: "
 	tail -c 27 "${1}"
 }

 # $1: input file ; $2: output file ; $3: what kind of file
 mptcp_lib_check_transfer() {
 	local in="${1}"
 	local out="${2}"
 	local what="${3}"

 	if ! cmp "$in" "$out" > /dev/null 2>&1; then
 		mptcp_lib_pr_fail "$what does not match (in, out):"
 		mptcp_lib_print_file_err "$in"
 		mptcp_lib_print_file_err "$out"

 		return 1
 	fi

 	return 0
 }

 # $1: ns, $2: port
 mptcp_lib_wait_local_port_listen() {
 	wait_local_port_listen "${@}" "tcp"
 }

 mptcp_lib_check_output() {
 	local err="${1}"
 	local cmd="${2}"
 	local expected="${3}"
 	local cmd_ret=0
 	local out

 	if ! out=$(${cmd} 2>"${err}"); then
 		cmd_ret=${?}
 	fi

 	if [ ${cmd_ret} -ne 0 ]; then
 		mptcp_lib_pr_fail "command execution '${cmd}' stderr"
 		cat "${err}"
 		return 2
 	elif [ "${out}" = "${expected}" ]; then
 		return 0
 	else
 		mptcp_lib_pr_fail "expected '${expected}' got '${out}'"
 		return 1
 	fi
 }

 mptcp_lib_check_tools() {
 	local tool

 	for tool in "${@}"; do
 		case "${tool}" in
 		"ip")
 			if ! ip -Version &> /dev/null; then
 				mptcp_lib_pr_skip "Could not run test without ip tool"
 				exit ${KSFT_SKIP}
 			fi
 			;;
 		"tc")
 			if ! tc -help &> /dev/null; then
 				mptcp_lib_pr_skip "Could not run test without tc tool"
 				exit ${KSFT_SKIP}
 			fi
 			;;
 		"ss")
 			if ! ss -h | grep -q MPTCP; then
 				mptcp_lib_pr_skip "ss tool does not support MPTCP"
 				exit ${KSFT_SKIP}
 			fi
 			;;
 		"iptables"* | "ip6tables"*)
 			if ! "${tool}" -V &> /dev/null; then
 				mptcp_lib_pr_skip "Could not run all tests without ${tool}"
 				exit ${KSFT_SKIP}
 			fi
 			;;
 		*)
 			mptcp_lib_pr_fail "Internal error: unsupported tool: ${tool}"
 			exit ${KSFT_FAIL}
 			;;
 		esac
 	done
 }

 mptcp_lib_ns_init() {
 	if ! setup_ns "${@}"; then
 		mptcp_lib_pr_fail "Failed to setup namespaces ${*}"
 		exit ${KSFT_FAIL}
 	fi

 	local netns
 	for netns in "${@}"; do
 		ip netns exec "${!netns}" sysctl -q net.mptcp.enabled=1
 		ip netns exec "${!netns}" sysctl -q net.ipv4.conf.all.rp_filter=0
 		ip netns exec "${!netns}" sysctl -q net.ipv4.conf.default.rp_filter=0
 	done
 }

 mptcp_lib_ns_exit() {
 	cleanup_ns "${@}"

 	local netns
 	for netns in "${@}"; do
 		rm -f /tmp/"${netns}".{nstat,out}
 	done
 }

 mptcp_lib_events() {
 	local ns="${1}"
 	local evts="${2}"
 	declare -n pid="${3}"

 	:>"${evts}"

 	mptcp_lib_kill_wait "${pid:-0}"
 	ip netns exec "${ns}" ./pm_nl_ctl events >> "${evts}" 2>&1 &
 	pid=$!
 }

 mptcp_lib_print_title() {
 	: "${MPTCP_LIB_TEST_COUNTER:?}"
 	: "${MPTCP_LIB_TEST_FORMAT:?}"

 	# shellcheck disable=SC2059 # the format is in a variable
 	printf "${MPTCP_LIB_TEST_FORMAT}" "$((++MPTCP_LIB_TEST_COUNTER))" "${*}"
 }

 # $1: var name ; $2: prev ret
 mptcp_lib_check_expected_one() {
 	local var="${1}"
 	local exp="e_${var}"
 	local prev_ret="${2}"

 	if [ "${!var}" = "${!exp}" ]; then
 		return 0
 	fi

 	if [ "${prev_ret}" = "0" ]; then
 		mptcp_lib_pr_fail
 	fi

 	mptcp_lib_print_err "Expected value for '${var}': '${!exp}', got '${!var}'."
 	return 1
 }

 # $@: all var names to check
 mptcp_lib_check_expected() {
 	local rc=0
 	local var

 	for var in "${@}"; do
 		mptcp_lib_check_expected_one "${var}" "${rc}" || rc=1
 	done

 	return "${rc}"
 }

 # shellcheck disable=SC2034 # Some variables are used below but indirectly
 mptcp_lib_verify_listener_events() {
 	local evt=${1}
 	local e_type=${2}
 	local e_family=${3}
 	local e_saddr=${4}
 	local e_sport=${5}
 	local type
 	local family
 	local saddr
 	local sport
 	local rc=0

 	type=$(mptcp_lib_evts_get_info type "${evt}" "${e_type}")
 	family=$(mptcp_lib_evts_get_info family "${evt}" "${e_type}")
 	if [ "${family}" ] && [ "${family}" = "${AF_INET6}" ]; then
 		saddr=$(mptcp_lib_evts_get_info saddr6 "${evt}" "${e_type}")
 	else
 		saddr=$(mptcp_lib_evts_get_info saddr4 "${evt}" "${e_type}")
 	fi
 	sport=$(mptcp_lib_evts_get_info sport "${evt}" "${e_type}")

 	mptcp_lib_check_expected "type" "family" "saddr" "sport" || rc="${?}"
 	return "${rc}"
 }

 mptcp_lib_set_ip_mptcp() {
 	MPTCP_LIB_IP_MPTCP=1
 }

 mptcp_lib_is_ip_mptcp() {
 	[ "${MPTCP_LIB_IP_MPTCP}" = "1" ]
 }

 # format: <id>,<ip>,<flags>,<dev>
 mptcp_lib_pm_nl_format_endpoints() {
 	local entry id ip flags dev port

 	for entry in "${@}"; do
 		IFS=, read -r id ip flags dev port <<< "${entry}"
 		if mptcp_lib_is_ip_mptcp; then
 			echo -n "${ip}"
 			[ -n "${port}" ] && echo -n " port ${port}"
 			echo -n " id ${id}"
 			[ -n "${flags}" ] && echo -n " ${flags}"
 			[ -n "${dev}" ] && echo -n " dev ${dev}"
 			echo " " # always a space at the end
 		else
 			echo -n "id ${id}"
 			echo -n " flags ${flags//" "/","}"
 			[ -n "${dev}" ] && echo -n " dev ${dev}"
 			echo -n " ${ip}"
 			[ -n "${port}" ] && echo -n " ${port}"
 			echo ""
 		fi
 	done
 }

 mptcp_lib_pm_nl_get_endpoint() {
 	local ns=${1}
 	local id=${2}

 	if mptcp_lib_is_ip_mptcp; then
 		ip -n "${ns}" mptcp endpoint show id "${id}"
 	else
 		ip netns exec "${ns}" ./pm_nl_ctl get "${id}"
 	fi
 }

 mptcp_lib_pm_nl_set_limits() {
 	local ns=${1}
 	local addrs=${2}
 	local subflows=${3}

 	if mptcp_lib_is_ip_mptcp; then
 		ip -n "${ns}" mptcp limits set add_addr_accepted "${addrs}" subflows "${subflows}"
 	else
 		ip netns exec "${ns}" ./pm_nl_ctl limits "${addrs}" "${subflows}"
 	fi
 }

 mptcp_lib_pm_nl_add_endpoint() {
 	local ns=${1}
 	local addr=${2}
 	local flags dev id port
 	local nr=2

 	local p
 	for p in "${@}"; do
 		case "${p}" in
 		"flags" | "dev" | "id" | "port")
 			eval "${p}"=\$"${nr}"
 			;;
 		esac

 		nr=$((nr + 1))
 	done

 	if mptcp_lib_is_ip_mptcp; then
 		# shellcheck disable=SC2086 # blanks in flags, no double quote
 		ip -n "${ns}" mptcp endpoint add "${addr}" ${flags//","/" "} \
 			${dev:+dev "${dev}"} ${id:+id "${id}"} ${port:+port "${port}"}
 	else
 		ip netns exec "${ns}" ./pm_nl_ctl add "${addr}" ${flags:+flags "${flags}"} \
 			${dev:+dev "${dev}"} ${id:+id "${id}"} ${port:+port "${port}"}
 	fi
 }

 mptcp_lib_pm_nl_del_endpoint() {
 	local ns=${1}
 	local id=${2}
 	local addr=${3}

 	if mptcp_lib_is_ip_mptcp; then
 		[ "${id}" -ne 0 ] && addr=''
 		ip -n "${ns}" mptcp endpoint delete id "${id}" ${addr:+"${addr}"}
 	else
 		ip netns exec "${ns}" ./pm_nl_ctl del "${id}" "${addr}"
 	fi
 }

 mptcp_lib_pm_nl_flush_endpoint() {
 	local ns=${1}

 	if mptcp_lib_is_ip_mptcp; then
 		ip -n "${ns}" mptcp endpoint flush
 	else
 		ip netns exec "${ns}" ./pm_nl_ctl flush
 	fi
 }

 mptcp_lib_pm_nl_show_endpoints() {
 	local ns=${1}

 	if mptcp_lib_is_ip_mptcp; then
 		ip -n "${ns}" mptcp endpoint show
 	else
 		ip netns exec "${ns}" ./pm_nl_ctl dump
 	fi
 }

 mptcp_lib_pm_nl_change_endpoint() {
 	local ns=${1}
 	local id=${2}
 	local flags=${3}

 	if mptcp_lib_is_ip_mptcp; then
 		# shellcheck disable=SC2086 # blanks in flags, no double quote
 		ip -n "${ns}" mptcp endpoint change id "${id}" ${flags//","/" "}
 	else
 		ip netns exec "${ns}" ./pm_nl_ctl set id "${id}" flags "${flags}"
 	fi
 }
	#! /bin/bash
	# SPDX-License-Identifier: GPL-2.0

	. "$(dirname "${0}")/../lib.sh"
	. "$(dirname "${0}")/../net_helper.sh"

	readonly KSFT_PASS=0
	readonly KSFT_FAIL=1
	readonly KSFT_SKIP=4

	# shellcheck disable=SC2155 # declare and assign separately
	readonly KSFT_TEST="${MPTCP_LIB_KSFT_TEST:-$(basename "${0}" .sh)}"

	# These variables are used in some selftests, read-only
	declare -rx MPTCP_LIB_EVENT_CREATED=1 # MPTCP_EVENT_CREATED
	declare -rx MPTCP_LIB_EVENT_ESTABLISHED=2 # MPTCP_EVENT_ESTABLISHED
	declare -rx MPTCP_LIB_EVENT_CLOSED=3 # MPTCP_EVENT_CLOSED
	declare -rx MPTCP_LIB_EVENT_ANNOUNCED=6 # MPTCP_EVENT_ANNOUNCED
	declare -rx MPTCP_LIB_EVENT_REMOVED=7 # MPTCP_EVENT_REMOVED
	declare -rx MPTCP_LIB_EVENT_SUB_ESTABLISHED=10 # MPTCP_EVENT_SUB_ESTABLISHED
	declare -rx MPTCP_LIB_EVENT_SUB_CLOSED=11 # MPTCP_EVENT_SUB_CLOSED
	declare -rx MPTCP_LIB_EVENT_SUB_PRIORITY=13 # MPTCP_EVENT_SUB_PRIORITY
	declare -rx MPTCP_LIB_EVENT_LISTENER_CREATED=15 # MPTCP_EVENT_LISTENER_CREATED
	declare -rx MPTCP_LIB_EVENT_LISTENER_CLOSED=16 # MPTCP_EVENT_LISTENER_CLOSED

	declare -rx MPTCP_LIB_AF_INET=2
	declare -rx MPTCP_LIB_AF_INET6=10

	MPTCP_LIB_SUBTESTS=()
	MPTCP_LIB_SUBTESTS_DUPLICATED=0
	MPTCP_LIB_SUBTEST_FLAKY=0
	MPTCP_LIB_SUBTESTS_LAST_TS_MS=
	MPTCP_LIB_TEST_COUNTER=0
	MPTCP_LIB_TEST_FORMAT="%02u %-50s"
	MPTCP_LIB_IP_MPTCP=0

	# only if supported (or forced) and not disabled, see no-color.org
	if { [ -t 1 ] \|\| [ "${SELFTESTS_MPTCP_LIB_COLOR_FORCE:-}" = "1" ]; } &&
	[ "${NO_COLOR:-}" != "1" ]; then
	readonly MPTCP_LIB_COLOR_RED="\E[1;31m"
	readonly MPTCP_LIB_COLOR_GREEN="\E[1;32m"
	readonly MPTCP_LIB_COLOR_YELLOW="\E[1;33m"
	readonly MPTCP_LIB_COLOR_BLUE="\E[1;34m"
	readonly MPTCP_LIB_COLOR_RESET="\E[0m"
	else
	readonly MPTCP_LIB_COLOR_RED=
	readonly MPTCP_LIB_COLOR_GREEN=
	readonly MPTCP_LIB_COLOR_YELLOW=
	readonly MPTCP_LIB_COLOR_BLUE=
	readonly MPTCP_LIB_COLOR_RESET=
	fi

	# SELFTESTS_MPTCP_LIB_OVERRIDE_FLAKY env var can be set not to ignore errors
	# from subtests marked as flaky
	mptcp_lib_override_flaky() {
	[ "${SELFTESTS_MPTCP_LIB_OVERRIDE_FLAKY:-}" = 1 ]
	}

	mptcp_lib_subtest_is_flaky() {
	[ "${MPTCP_LIB_SUBTEST_FLAKY}" = 1 ] && ! mptcp_lib_override_flaky
	}

	# $1: color, $2: text
	mptcp_lib_print_color() {
	echo -e "${MPTCP_LIB_START_PRINT:-}${*}${MPTCP_LIB_COLOR_RESET}"
	}

	mptcp_lib_print_ok() {
	mptcp_lib_print_color "${MPTCP_LIB_COLOR_GREEN}${*}"
	}

	mptcp_lib_print_warn() {
	mptcp_lib_print_color "${MPTCP_LIB_COLOR_YELLOW}${*}"
	}

	mptcp_lib_print_info() {
	mptcp_lib_print_color "${MPTCP_LIB_COLOR_BLUE}${*}"
	}

	mptcp_lib_print_err() {
	mptcp_lib_print_color "${MPTCP_LIB_COLOR_RED}${*}"
	}

	# shellcheck disable=SC2120 # parameters are optional
	mptcp_lib_pr_ok() {
	mptcp_lib_print_ok "[ OK ]${1:+ ${*}}"
	}

	mptcp_lib_pr_skip() {
	mptcp_lib_print_warn "[SKIP]${1:+ ${*}}"
	}

	mptcp_lib_pr_fail() {
	local title cmt

	if mptcp_lib_subtest_is_flaky; then
	title="IGNO"
	cmt=" (flaky)"
	else
	title="FAIL"
	fi

	mptcp_lib_print_err "[${title}]${cmt}${1:+ ${*}}"
	}

	mptcp_lib_pr_info() {
	mptcp_lib_print_info "INFO: ${*}"
	}

	# SELFTESTS_MPTCP_LIB_EXPECT_ALL_FEATURES env var can be set when validating all
	# features using the last version of the kernel and the selftests to make sure
	# a test is not being skipped by mistake.
	mptcp_lib_expect_all_features() {
	[ "${SELFTESTS_MPTCP_LIB_EXPECT_ALL_FEATURES:-}" = "1" ]
	}

	# $1: msg
	mptcp_lib_fail_if_expected_feature() {
	if mptcp_lib_expect_all_features; then
	echo "ERROR: missing feature: ${*}"
	exit ${KSFT_FAIL}
	fi

	return 1
	}

	# $1: file
	mptcp_lib_has_file() {
	local f="${1}"

	if [ -f "${f}" ]; then
	return 0
	fi

	mptcp_lib_fail_if_expected_feature "${f} file not found"
	}

	mptcp_lib_check_mptcp() {
	if ! mptcp_lib_has_file "/proc/sys/net/mptcp/enabled"; then
	mptcp_lib_pr_skip "MPTCP support is not available"
	exit ${KSFT_SKIP}
	fi
	}

	mptcp_lib_check_kallsyms() {
	if ! mptcp_lib_has_file "/proc/kallsyms"; then
	mptcp_lib_pr_skip "CONFIG_KALLSYMS is missing"
	exit ${KSFT_SKIP}
	fi
	}

	# Internal: use mptcp_lib_kallsyms_has() instead
	__mptcp_lib_kallsyms_has() {
	local sym="${1}"

	mptcp_lib_check_kallsyms

	grep -q " ${sym}" /proc/kallsyms
	}

	# $1: part of a symbol to look at, add '$' at the end for full name
	mptcp_lib_kallsyms_has() {
	local sym="${1}"

	if __mptcp_lib_kallsyms_has "${sym}"; then
	return 0
	fi

	mptcp_lib_fail_if_expected_feature "${sym} symbol not found"
	}

	# $1: part of a symbol to look at, add '$' at the end for full name
	mptcp_lib_kallsyms_doesnt_have() {
	local sym="${1}"

	if ! __mptcp_lib_kallsyms_has "${sym}"; then
	return 0
	fi

	mptcp_lib_fail_if_expected_feature "${sym} symbol has been found"
	}

	# !!!AVOID USING THIS!!!
	# Features might not land in the expected version and features can be backported
	#
	# $1: kernel version, e.g. 6.3
	mptcp_lib_kversion_ge() {
	local exp_maj="${1%.*}"
	local exp_min="${1#*.}"
	local v maj min

	# If the kernel has backported features, set this env var to 1:
	if [ "${SELFTESTS_MPTCP_LIB_NO_KVERSION_CHECK:-}" = "1" ]; then
	return 0
	fi

	v=$(uname -r \| cut -d'.' -f1,2)
	maj=${v%.*}
	min=${v#*.}

	if [ "${maj}" -gt "${exp_maj}" ] \|\|
	{ [ "${maj}" -eq "${exp_maj}" ] && [ "${min}" -ge "${exp_min}" ]; }; then
	return 0
	fi

	mptcp_lib_fail_if_expected_feature "kernel version ${1} lower than ${v}"
	}

	mptcp_lib_subtests_last_ts_reset() {
	MPTCP_LIB_SUBTESTS_LAST_TS_MS="$(date +%s%3N)"
	}
	mptcp_lib_subtests_last_ts_reset

	__mptcp_lib_result_check_duplicated() {
	local subtest

	for subtest in "${MPTCP_LIB_SUBTESTS[@]}"; do
	if [[ "${subtest}" == " - ${KSFT_TEST}: ${%% #*}" ]]; then
	MPTCP_LIB_SUBTESTS_DUPLICATED=1
	mptcp_lib_print_err "Duplicated entry: ${*}"
	break
	fi
	done
	}

	__mptcp_lib_result_add() {
	local result="${1}"
	local time="time="
	local ts_prev_ms
	shift

	local id=$((${#MPTCP_LIB_SUBTESTS[@]} + 1))

	__mptcp_lib_result_check_duplicated "${*}"

	# not to add two '#'
	[[ "${}" != "#"* ]] && time="# ${time}"

	ts_prev_ms="${MPTCP_LIB_SUBTESTS_LAST_TS_MS}"
	mptcp_lib_subtests_last_ts_reset
	time+="$((MPTCP_LIB_SUBTESTS_LAST_TS_MS - ts_prev_ms))ms"

	MPTCP_LIB_SUBTESTS+=("${result} ${id} - ${KSFT_TEST}: ${*} ${time}")
	}

	# $1: test name
	mptcp_lib_result_pass() {
	__mptcp_lib_result_add "ok" "${1}"
	}

	# $1: test name
	mptcp_lib_result_fail() {
	if mptcp_lib_subtest_is_flaky; then
	# It might sound better to use 'not ok # TODO' or 'ok # SKIP',
	# but some CIs don't understand 'TODO' and treat SKIP as errors.
	__mptcp_lib_result_add "ok" "${1} # IGNORE Flaky"
	else
	__mptcp_lib_result_add "not ok" "${1}"
	fi
	}

	# $1: test name
	mptcp_lib_result_skip() {
	__mptcp_lib_result_add "ok" "${1} # SKIP"
	}

	# $1: result code ; $2: test name
	mptcp_lib_result_code() {
	local ret="${1}"
	local name="${2}"

	case "${ret}" in
	"${KSFT_PASS}")
	mptcp_lib_result_pass "${name}"
	;;
	"${KSFT_FAIL}")
	mptcp_lib_result_fail "${name}"
	;;
	"${KSFT_SKIP}")
	mptcp_lib_result_skip "${name}"
	;;
	*)
	echo "ERROR: wrong result code: ${ret}"
	exit ${KSFT_FAIL}
	;;
	esac
	}

	mptcp_lib_result_print_all_tap() {
	local subtest

	if [ ${#MPTCP_LIB_SUBTESTS[@]} -eq 0 ] \|\|
	[ "${SELFTESTS_MPTCP_LIB_NO_TAP:-}" = "1" ]; then
	return
	fi

	printf "\nTAP version 13\n"
	printf "1..%d\n" "${#MPTCP_LIB_SUBTESTS[@]}"

	for subtest in "${MPTCP_LIB_SUBTESTS[@]}"; do
	printf "%s\n" "${subtest}"
	done

	if [ "${MPTCP_LIB_SUBTESTS_DUPLICATED}" = 1 ] &&
	mptcp_lib_expect_all_features; then
	mptcp_lib_print_err "Duplicated test entries"
	exit ${KSFT_FAIL}
	fi
	}

	# get the value of keyword $1 in the line marked by keyword $2
	mptcp_lib_get_info_value() {
	grep "${2}" \| sed -n 's/.\('"${1}"':\)\([0-9a-f:.]\).*$/\2/p;q'
	}

	# $1: info name ; $2: evts_ns ; [$3: event type; [$4: addr]]
	mptcp_lib_evts_get_info() {
	grep "${4:-}" "${2}" \| mptcp_lib_get_info_value "${1}" "^type:${3:-1},"
	}

	# $1: PID
	mptcp_lib_kill_wait() {
	[ "${1}" -eq 0 ] && return 0

	kill -SIGUSR1 "${1}" > /dev/null 2>&1
	kill "${1}" > /dev/null 2>&1
	wait "${1}" 2>/dev/null
	}

	# $1: IP address
	mptcp_lib_is_v6() {
	[ -z "${1##:}" ]
	}

	# $1: ns, $2: MIB counter
	mptcp_lib_get_counter() {
	local ns="${1}"
	local counter="${2}"
	local count

	count=$(ip netns exec "${ns}" nstat -asz "${counter}" \|
	awk 'NR==1 {next} {print $2}')
	if [ -z "${count}" ]; then
	mptcp_lib_fail_if_expected_feature "${counter} counter"
	return 1
	fi

	echo "${count}"
	}

	mptcp_lib_make_file() {
	local name="${1}"
	local bs="${2}"
	local size="${3}"

	dd if=/dev/urandom of="${name}" bs="${bs}" count="${size}" 2> /dev/null
	echo -e "\nMPTCP_TEST_FILE_END_MARKER" >> "${name}"
	}

	# $1: file
	mptcp_lib_print_file_err() {
	ls -l "${1}" 1>&2
	echo "Trailing bytes are: "
	tail -c 27 "${1}"
	}

	# $1: input file ; $2: output file ; $3: what kind of file
	mptcp_lib_check_transfer() {
	local in="${1}"
	local out="${2}"
	local what="${3}"

	if ! cmp "$in" "$out" > /dev/null 2>&1; then
	mptcp_lib_pr_fail "$what does not match (in, out):"
	mptcp_lib_print_file_err "$in"
	mptcp_lib_print_file_err "$out"

	return 1
	fi

	return 0
	}

	# $1: ns, $2: port
	mptcp_lib_wait_local_port_listen() {
	wait_local_port_listen "${@}" "tcp"
	}

	mptcp_lib_check_output() {
	local err="${1}"
	local cmd="${2}"
	local expected="${3}"
	local cmd_ret=0
	local out

	if ! out=$(${cmd} 2>"${err}"); then
	cmd_ret=${?}
	fi

	if [ ${cmd_ret} -ne 0 ]; then
	mptcp_lib_pr_fail "command execution '${cmd}' stderr"
	cat "${err}"
	return 2
	elif [ "${out}" = "${expected}" ]; then
	return 0
	else
	mptcp_lib_pr_fail "expected '${expected}' got '${out}'"
	return 1
	fi
	}

	mptcp_lib_check_tools() {
	local tool

	for tool in "${@}"; do
	case "${tool}" in
	"ip")
	if ! ip -Version &> /dev/null; then
	mptcp_lib_pr_skip "Could not run test without ip tool"
	exit ${KSFT_SKIP}
	fi
	;;
	"tc")
	if ! tc -help &> /dev/null; then
	mptcp_lib_pr_skip "Could not run test without tc tool"
	exit ${KSFT_SKIP}
	fi
	;;
	"ss")
	if ! ss -h \| grep -q MPTCP; then
	mptcp_lib_pr_skip "ss tool does not support MPTCP"
	exit ${KSFT_SKIP}
	fi
	;;
	"iptables"* \| "ip6tables"*)
	if ! "${tool}" -V &> /dev/null; then
	mptcp_lib_pr_skip "Could not run all tests without ${tool}"
	exit ${KSFT_SKIP}
	fi
	;;
	*)
	mptcp_lib_pr_fail "Internal error: unsupported tool: ${tool}"
	exit ${KSFT_FAIL}
	;;
	esac
	done
	}

	mptcp_lib_ns_init() {
	if ! setup_ns "${@}"; then
	mptcp_lib_pr_fail "Failed to setup namespaces ${*}"
	exit ${KSFT_FAIL}
	fi

	local netns
	for netns in "${@}"; do
	ip netns exec "${!netns}" sysctl -q net.mptcp.enabled=1
	ip netns exec "${!netns}" sysctl -q net.ipv4.conf.all.rp_filter=0
	ip netns exec "${!netns}" sysctl -q net.ipv4.conf.default.rp_filter=0
	done
	}

	mptcp_lib_ns_exit() {
	cleanup_ns "${@}"

	local netns
	for netns in "${@}"; do
	rm -f /tmp/"${netns}".{nstat,out}
	done
	}

	mptcp_lib_events() {
	local ns="${1}"
	local evts="${2}"
	declare -n pid="${3}"

	:>"${evts}"

	mptcp_lib_kill_wait "${pid:-0}"
	ip netns exec "${ns}" ./pm_nl_ctl events >> "${evts}" 2>&1 &
	pid=$!
	}

	mptcp_lib_print_title() {
	: "${MPTCP_LIB_TEST_COUNTER:?}"
	: "${MPTCP_LIB_TEST_FORMAT:?}"

	# shellcheck disable=SC2059 # the format is in a variable
	printf "${MPTCP_LIB_TEST_FORMAT}" "$((++MPTCP_LIB_TEST_COUNTER))" "${*}"
	}

	# $1: var name ; $2: prev ret
	mptcp_lib_check_expected_one() {
	local var="${1}"
	local exp="e_${var}"
	local prev_ret="${2}"

	if [ "${!var}" = "${!exp}" ]; then
	return 0
	fi

	if [ "${prev_ret}" = "0" ]; then
	mptcp_lib_pr_fail
	fi

	mptcp_lib_print_err "Expected value for '${var}': '${!exp}', got '${!var}'."
	return 1
	}

	# $@: all var names to check
	mptcp_lib_check_expected() {
	local rc=0
	local var

	for var in "${@}"; do
	mptcp_lib_check_expected_one "${var}" "${rc}" \|\| rc=1
	done

	return "${rc}"
	}

	# shellcheck disable=SC2034 # Some variables are used below but indirectly
	mptcp_lib_verify_listener_events() {
	local evt=${1}
	local e_type=${2}
	local e_family=${3}
	local e_saddr=${4}
	local e_sport=${5}
	local type
	local family
	local saddr
	local sport
	local rc=0

	type=$(mptcp_lib_evts_get_info type "${evt}" "${e_type}")
	family=$(mptcp_lib_evts_get_info family "${evt}" "${e_type}")
	if [ "${family}" ] && [ "${family}" = "${AF_INET6}" ]; then
	saddr=$(mptcp_lib_evts_get_info saddr6 "${evt}" "${e_type}")
	else
	saddr=$(mptcp_lib_evts_get_info saddr4 "${evt}" "${e_type}")
	fi
	sport=$(mptcp_lib_evts_get_info sport "${evt}" "${e_type}")

	mptcp_lib_check_expected "type" "family" "saddr" "sport" \|\| rc="${?}"
	return "${rc}"
	}

	mptcp_lib_set_ip_mptcp() {
	MPTCP_LIB_IP_MPTCP=1
	}

	mptcp_lib_is_ip_mptcp() {
	[ "${MPTCP_LIB_IP_MPTCP}" = "1" ]
	}

	# format: <id>,<ip>,<flags>,<dev>
	mptcp_lib_pm_nl_format_endpoints() {
	local entry id ip flags dev port

	for entry in "${@}"; do
	IFS=, read -r id ip flags dev port <<< "${entry}"
	if mptcp_lib_is_ip_mptcp; then
	echo -n "${ip}"
	[ -n "${port}" ] && echo -n " port ${port}"
	echo -n " id ${id}"
	[ -n "${flags}" ] && echo -n " ${flags}"
	[ -n "${dev}" ] && echo -n " dev ${dev}"
	echo " " # always a space at the end
	else
	echo -n "id ${id}"
	echo -n " flags ${flags//" "/","}"
	[ -n "${dev}" ] && echo -n " dev ${dev}"
	echo -n " ${ip}"
	[ -n "${port}" ] && echo -n " ${port}"
	echo ""
	fi
	done
	}

	mptcp_lib_pm_nl_get_endpoint() {
	local ns=${1}
	local id=${2}

	if mptcp_lib_is_ip_mptcp; then
	ip -n "${ns}" mptcp endpoint show id "${id}"
	else
	ip netns exec "${ns}" ./pm_nl_ctl get "${id}"
	fi
	}

	mptcp_lib_pm_nl_set_limits() {
	local ns=${1}
	local addrs=${2}
	local subflows=${3}

	if mptcp_lib_is_ip_mptcp; then
	ip -n "${ns}" mptcp limits set add_addr_accepted "${addrs}" subflows "${subflows}"
	else
	ip netns exec "${ns}" ./pm_nl_ctl limits "${addrs}" "${subflows}"
	fi
	}

	mptcp_lib_pm_nl_add_endpoint() {
	local ns=${1}
	local addr=${2}
	local flags dev id port
	local nr=2

	local p
	for p in "${@}"; do
	case "${p}" in
	"flags" \| "dev" \| "id" \| "port")
	eval "${p}"=\$"${nr}"
	;;
	esac

	nr=$((nr + 1))
	done

	if mptcp_lib_is_ip_mptcp; then
	# shellcheck disable=SC2086 # blanks in flags, no double quote
	ip -n "${ns}" mptcp endpoint add "${addr}" ${flags//","/" "} \
	${dev:+dev "${dev}"} ${id:+id "${id}"} ${port:+port "${port}"}
	else
	ip netns exec "${ns}" ./pm_nl_ctl add "${addr}" ${flags:+flags "${flags}"} \
	${dev:+dev "${dev}"} ${id:+id "${id}"} ${port:+port "${port}"}
	fi
	}

	mptcp_lib_pm_nl_del_endpoint() {
	local ns=${1}
	local id=${2}
	local addr=${3}

	if mptcp_lib_is_ip_mptcp; then
	[ "${id}" -ne 0 ] && addr=''
	ip -n "${ns}" mptcp endpoint delete id "${id}" ${addr:+"${addr}"}
	else
	ip netns exec "${ns}" ./pm_nl_ctl del "${id}" "${addr}"
	fi
	}

	mptcp_lib_pm_nl_flush_endpoint() {
	local ns=${1}

	if mptcp_lib_is_ip_mptcp; then
	ip -n "${ns}" mptcp endpoint flush
	else
	ip netns exec "${ns}" ./pm_nl_ctl flush
	fi
	}

	mptcp_lib_pm_nl_show_endpoints() {
	local ns=${1}

	if mptcp_lib_is_ip_mptcp; then
	ip -n "${ns}" mptcp endpoint show
	else
	ip netns exec "${ns}" ./pm_nl_ctl dump
	fi
	}

	mptcp_lib_pm_nl_change_endpoint() {
	local ns=${1}
	local id=${2}
	local flags=${3}

	if mptcp_lib_is_ip_mptcp; then
	# shellcheck disable=SC2086 # blanks in flags, no double quote
	ip -n "${ns}" mptcp endpoint change id "${id}" ${flags//","/" "}
	else
	ip netns exec "${ns}" ./pm_nl_ctl set id "${id}" flags "${flags}"
	fi
	}