Merge branch 'mptcp-pm-listener-events-selftests-cleanup'

Matthieu Baerts says:

====================
mptcp: PM listener events + selftests cleanup

Thanks to the patch 6/11, the MPTCP path manager now sends Netlink events
when MPTCP listening sockets are created and closed. The reason why it is
needed is explained in the linked ticket [1]:

  MPTCP for Linux, when not using the in-kernel PM, depends on the
  userspace PM to create extra listening sockets before announcing
  addresses and ports. Let's call these "PM listeners".

  With the existing MPTCP netlink events, a userspace PM can create
  PM listeners at startup time, or in response to an incoming connection.
  Creating sockets in response to connections is not optimal: ADD_ADDRs
  can't be sent until the sockets are created and listen()ed, and if all
  connections are closed then it may not be clear to the userspace
  PM daemon that PM listener sockets should be cleaned up.

  Hence this feature request: to add MPTCP netlink events for listening
  socket close & create, so PM listening sockets can be managed based
  on application activity.

  [1] https://github.com/multipath-tcp/mptcp_net-next/issues/313

Selftests for these new Netlink events have been added in patches 9,11/11.

The remaining patches introduce different cleanups and small improvements
in MPTCP selftests to ease the maintenance and the addition of new tests.
====================

Link: https://lore.kernel.org/r/20221130140637.409926-1-matthieu.baerts@tessares.netSigned-off-by: Jakub Kicinski <kuba@kernel.org>

include/uapi/linux/mptcp.h

@@ -160,6 +160,12 @@ struct mptcp_info {
  *                           daddr4 | daddr6, sport, dport, backup, if_idx
  *                           [, error]
  * The priority of a subflow has changed. 'error' should not be set.
+ *
+ * MPTCP_EVENT_LISTENER_CREATED: family, sport, saddr4 | saddr6
+ * A new PM listener is created.
+ *
+ * MPTCP_EVENT_LISTENER_CLOSED: family, sport, saddr4 | saddr6
+ * A PM listener is closed.
  */
 enum mptcp_event_type {
 	MPTCP_EVENT_UNSPEC = 0,
@@ -174,6 +180,9 @@ enum mptcp_event_type {
 	MPTCP_EVENT_SUB_CLOSED = 11,
 
 	MPTCP_EVENT_SUB_PRIORITY = 13,
+
+	MPTCP_EVENT_LISTENER_CREATED = 15,
+	MPTCP_EVENT_LISTENER_CLOSED = 16,
 };
 
 enum mptcp_event_attr {

net/mptcp/pm_netlink.c

@@ -1029,6 +1029,8 @@ static int mptcp_pm_nl_create_listen_socket(struct sock *sk,
 	if (err)
 		return err;
 
+	mptcp_event_pm_listener(ssock->sk, MPTCP_EVENT_LISTENER_CREATED);
+
 	return 0;
 }
 
@@ -2152,6 +2154,58 @@ void mptcp_event_addr_announced(const struct sock *ssk,
 	kfree_skb(skb);
 }
 
+void mptcp_event_pm_listener(const struct sock *ssk,
+			     enum mptcp_event_type event)
+{
+	const struct inet_sock *issk = inet_sk(ssk);
+	struct net *net = sock_net(ssk);
+	struct nlmsghdr *nlh;
+	struct sk_buff *skb;
+
+	if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET))
+		return;
+
+	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+	if (!skb)
+		return;
+
+	nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, event);
+	if (!nlh)
+		goto nla_put_failure;
+
+	if (nla_put_u16(skb, MPTCP_ATTR_FAMILY, ssk->sk_family))
+		goto nla_put_failure;
+
+	if (nla_put_be16(skb, MPTCP_ATTR_SPORT, issk->inet_sport))
+		goto nla_put_failure;
+
+	switch (ssk->sk_family) {
+	case AF_INET:
+		if (nla_put_in_addr(skb, MPTCP_ATTR_SADDR4, issk->inet_saddr))
+			goto nla_put_failure;
+		break;
+#if IS_ENABLED(CONFIG_MPTCP_IPV6)
+	case AF_INET6: {
+		const struct ipv6_pinfo *np = inet6_sk(ssk);
+
+		if (nla_put_in6_addr(skb, MPTCP_ATTR_SADDR6, &np->saddr))
+			goto nla_put_failure;
+		break;
+	}
+#endif
+	default:
+		WARN_ON_ONCE(1);
+		goto nla_put_failure;
+	}
+
+	genlmsg_end(skb, nlh);
+	mptcp_nl_mcast_send(net, skb, GFP_KERNEL);
+	return;
+
+nla_put_failure:
+	kfree_skb(skb);
+}
+
 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk,
 		 const struct sock *ssk, gfp_t gfp)
 {
@@ -2197,6 +2251,9 @@ void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk,
 		if (mptcp_event_sub_closed(skb, msk, ssk) < 0)
 			goto nla_put_failure;
 		break;
+	case MPTCP_EVENT_LISTENER_CREATED:
+	case MPTCP_EVENT_LISTENER_CLOSED:
+		break;
 	}
 
 	genlmsg_end(skb, nlh);

net/mptcp/protocol.c

@@ -2355,6 +2355,7 @@ static void __mptcp_close_ssk(struct sock *sk, struct sock *ssk,
 			tcp_set_state(ssk, TCP_CLOSE);
 			mptcp_subflow_queue_clean(ssk);
 			inet_csk_listen_stop(ssk);
+			mptcp_event_pm_listener(ssk, MPTCP_EVENT_LISTENER_CLOSED);
 		}
 		__tcp_close(ssk, 0);
 
@@ -3647,6 +3648,8 @@ static int mptcp_listen(struct socket *sock, int backlog)
 	if (!err)
 		mptcp_copy_inaddrs(sock->sk, ssock->sk);
 
+	mptcp_event_pm_listener(ssock->sk, MPTCP_EVENT_LISTENER_CREATED);
+
 unlock:
 	release_sock(sock->sk);
 	return err;

net/mptcp/protocol.h

@@ -839,6 +839,8 @@ void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk,
 		 const struct sock *ssk, gfp_t gfp);
 void mptcp_event_addr_announced(const struct sock *ssk, const struct mptcp_addr_info *info);
 void mptcp_event_addr_removed(const struct mptcp_sock *msk, u8 id);
+void mptcp_event_pm_listener(const struct sock *ssk,
+			     enum mptcp_event_type event);
 bool mptcp_userspace_pm_active(const struct mptcp_sock *msk);
 
 void mptcp_fastopen_gen_msk_ackseq(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow,

tools/testing/selftests/net/mptcp/diag.sh

 #!/bin/bash
 # SPDX-License-Identifier: GPL-2.0
 
+sec=$(date +%s)
 rndh=$(printf %x $sec)-$(mktemp -u XXXXXX)
 ns="ns1-$rndh"
 ksft_skip=4

tools/testing/selftests/net/mptcp/mptcp_connect.sh

@@ -274,8 +274,7 @@ check_transfer()
 
 check_mptcp_disabled()
 {
-	local disabled_ns
-	disabled_ns="ns_disabled-$sech-$(mktemp -u XXXXXX)"
+	local disabled_ns="ns_disabled-$rndh"
 	ip netns add ${disabled_ns} || exit $ksft_skip
 
 	# net.mptcp.enabled should be enabled by default
@@ -781,7 +780,6 @@ run_tests_mptfo()
 
 run_tests_disconnect()
 {
-	local peekmode="$1"
 	local old_cin=$cin
 	local old_sin=$sin
 
@@ -789,7 +787,6 @@ run_tests_disconnect()
 
 	# force do_transfer to cope with the multiple tranmissions
 	sin="$cin.disconnect"
-	sin_disconnect=$old_sin
 	cin="$cin.disconnect"
 	cin_disconnect="$old_cin"
 	connect_per_transfer=3
@@ -800,7 +797,6 @@ run_tests_disconnect()
 
 	# restore previous status
 	sin=$old_sin
-	sin_disconnect="$cout".disconnect
 	cin=$old_cin
 	cin_disconnect="$cin".disconnect
 	connect_per_transfer=1

tools/testing/selftests/net/mptcp/mptcp_join.sh

@@ -26,6 +26,10 @@ ip_mptcp=0
 check_invert=0
 validate_checksum=0
 init=0
+evts_ns1=""
+evts_ns2=""
+evts_ns1_pid=0
+evts_ns2_pid=0
 
 declare -A all_tests
 declare -a only_tests_ids
@@ -59,8 +63,9 @@ init_partial()
 {
 	capout=$(mktemp)
 
-	local rndh
-	rndh=$(mktemp -u XXXXXX)
+	local sec rndh
+	sec=$(date +%s)
+	rndh=$(printf %x $sec)-$(mktemp -u XXXXXX)
 
 	ns1="ns1-$rndh"
 	ns2="ns2-$rndh"
@@ -153,6 +158,8 @@ init() {
 	cin=$(mktemp)
 	cinsent=$(mktemp)
 	cout=$(mktemp)
+	evts_ns1=$(mktemp)
+	evts_ns2=$(mktemp)
 
 	trap cleanup EXIT
 
@@ -164,6 +171,7 @@ cleanup()
 {
 	rm -f "$cin" "$cout" "$sinfail"
 	rm -f "$sin" "$sout" "$cinsent" "$cinfail"
+	rm -rf $evts_ns1 $evts_ns2
 	cleanup_partial
 }
 
@@ -319,6 +327,18 @@ reset_with_fail()
 		index 100 || exit 1
 }
 
+reset_with_events()
+{
+	reset "${1}" || return 1
+
+	:> "$evts_ns1"
+	:> "$evts_ns2"
+	ip netns exec $ns1 ./pm_nl_ctl events >> "$evts_ns1" 2>&1 &
+	evts_ns1_pid=$!
+	ip netns exec $ns2 ./pm_nl_ctl events >> "$evts_ns2" 2>&1 &
+	evts_ns2_pid=$!
+}
+
 fail_test()
 {
 	ret=1
@@ -472,6 +492,12 @@ kill_wait()
 	wait $1 2>/dev/null
 }
 
+kill_events_pids()
+{
+	kill_wait $evts_ns1_pid
+	kill_wait $evts_ns2_pid
+}
+
 pm_nl_set_limits()
 {
 	local ns=$1
@@ -672,10 +698,6 @@ do_transfer()
 	local port=$((10000 + TEST_COUNT - 1))
 	local cappid
 	local userspace_pm=0
-	local evts_ns1
-	local evts_ns1_pid
-	local evts_ns2
-	local evts_ns2_pid
 
 	:> "$cout"
 	:> "$sout"
@@ -752,17 +774,6 @@ do_transfer()
 		addr_nr_ns2=${addr_nr_ns2:9}
 	fi
 
-	if [ $userspace_pm -eq 1 ]; then
-		evts_ns1=$(mktemp)
-		evts_ns2=$(mktemp)
-		:> "$evts_ns1"
-		:> "$evts_ns2"
-		ip netns exec ${listener_ns} ./pm_nl_ctl events >> "$evts_ns1" 2>&1 &
-		evts_ns1_pid=$!
-		ip netns exec ${connector_ns} ./pm_nl_ctl events >> "$evts_ns2" 2>&1 &
-		evts_ns2_pid=$!
-	fi
-
 	local local_addr
 	if is_v6 "${connect_addr}"; then
 		local_addr="::"
@@ -829,7 +840,8 @@ do_transfer()
 			if [ $userspace_pm -eq 0 ]; then
 				pm_nl_add_endpoint $ns1 $addr flags signal
 			else
-				tk=$(sed -n 's/.*\(token:\)\([[:digit:]]*\).*$/\2/p;q' "$evts_ns1")
+				tk=$(grep "type:1," "$evts_ns1" |
+				     sed -n 's/.*\(token:\)\([[:digit:]]*\).*$/\2/p;q')
 				ip netns exec ${listener_ns} ./pm_nl_ctl ann $addr token $tk id $id
 				sleep 1
 				ip netns exec ${listener_ns} ./pm_nl_ctl rem token $tk id $id
@@ -980,12 +992,6 @@ do_transfer()
 	    kill $cappid
 	fi
 
-	if [ $userspace_pm -eq 1 ]; then
-		kill_wait $evts_ns1_pid
-		kill_wait $evts_ns2_pid
-		rm -rf $evts_ns1 $evts_ns2
-	fi
-
 	NSTAT_HISTORY=/tmp/${listener_ns}.nstat ip netns exec ${listener_ns} \
 		nstat | grep Tcp > /tmp/${listener_ns}.out
 	NSTAT_HISTORY=/tmp/${connector_ns}.nstat ip netns exec ${connector_ns} \
@@ -2507,6 +2513,57 @@ backup_tests()
 	fi
 }
 
+LISTENER_CREATED=15 #MPTCP_EVENT_LISTENER_CREATED
+LISTENER_CLOSED=16  #MPTCP_EVENT_LISTENER_CLOSED
+
+AF_INET=2
+AF_INET6=10
+
+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
+
+	if [ $e_type = $LISTENER_CREATED ]; then
+		stdbuf -o0 -e0 printf "\t\t\t\t\t CREATE_LISTENER %s:%s"\
+			$e_saddr $e_sport
+	elif [ $e_type = $LISTENER_CLOSED ]; then
+		stdbuf -o0 -e0 printf "\t\t\t\t\t CLOSE_LISTENER %s:%s "\
+			$e_saddr $e_sport
+	fi
+
+	type=$(grep "type:$e_type," $evt |
+	       sed --unbuffered -n 's/.*\(type:\)\([[:digit:]]*\).*$/\2/p;q')
+	family=$(grep "type:$e_type," $evt |
+		 sed --unbuffered -n 's/.*\(family:\)\([[:digit:]]*\).*$/\2/p;q')
+	sport=$(grep "type:$e_type," $evt |
+		sed --unbuffered -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q')
+	if [ $family ] && [ $family = $AF_INET6 ]; then
+		saddr=$(grep "type:$e_type," $evt |
+			sed --unbuffered -n 's/.*\(saddr6:\)\([0-9a-f:.]*\).*$/\2/p;q')
+	else
+		saddr=$(grep "type:$e_type," $evt |
+			sed --unbuffered -n 's/.*\(saddr4:\)\([0-9.]*\).*$/\2/p;q')
+	fi
+
+	if [ $type ] && [ $type = $e_type ] &&
+	   [ $family ] && [ $family = $e_family ] &&
+	   [ $saddr ] && [ $saddr = $e_saddr ] &&
+	   [ $sport ] && [ $sport = $e_sport ]; then
+		stdbuf -o0 -e0 printf "[ ok ]\n"
+		return 0
+	fi
+	fail_test
+	stdbuf -o0 -e0 printf "[fail]\n"
+}
+
 add_addr_ports_tests()
 {
 	# signal address with port
@@ -2531,7 +2588,8 @@ add_addr_ports_tests()
 	fi
 
 	# single address with port, remove
-	if reset "remove single address with port"; then
+	# pm listener events
+	if reset_with_events "remove single address with port"; then
 		pm_nl_set_limits $ns1 0 1
 		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal port 10100
 		pm_nl_set_limits $ns2 1 1
@@ -2539,6 +2597,10 @@ add_addr_ports_tests()
 		chk_join_nr 1 1 1
 		chk_add_nr 1 1 1
 		chk_rm_nr 1 1 invert
+
+		verify_listener_events $evts_ns1 $LISTENER_CREATED $AF_INET 10.0.2.1 10100
+		verify_listener_events $evts_ns1 $LISTENER_CLOSED $AF_INET 10.0.2.1 10100
+		kill_events_pids
 	fi
 
 	# subflow and signal with port, remove
@@ -2959,22 +3021,24 @@ userspace_tests()
 	fi
 
 	# userspace pm add & remove address
-	if reset "userspace pm add & remove address"; then
+	if reset_with_events "userspace pm add & remove address"; then
 		set_userspace_pm $ns1
 		pm_nl_set_limits $ns2 1 1
 		run_tests $ns1 $ns2 10.0.1.1 0 userspace_1 0 slow
 		chk_join_nr 1 1 1
 		chk_add_nr 1 1
 		chk_rm_nr 1 1 invert
+		kill_events_pids
 	fi
 
 	# userspace pm create destroy subflow
-	if reset "userspace pm create destroy subflow"; then
+	if reset_with_events "userspace pm create destroy subflow"; then
 		set_userspace_pm $ns2
 		pm_nl_set_limits $ns1 0 1
 		run_tests $ns1 $ns2 10.0.1.1 0 0 userspace_1 slow
 		chk_join_nr 1 1 1
 		chk_rm_nr 0 1
+		kill_events_pids
 	fi
 }
 

tools/testing/selftests/net/mptcp/mptcp_sockopt.sh

@@ -10,13 +10,19 @@ ksft_skip=4
 timeout_poll=30
 timeout_test=$((timeout_poll * 2 + 1))
 mptcp_connect=""
-do_all_tests=1
+
+sec=$(date +%s)
+rndh=$(printf %x $sec)-$(mktemp -u XXXXXX)
+ns1="ns1-$rndh"
+ns2="ns2-$rndh"
+ns_sbox="ns_sbox-$rndh"
 
 add_mark_rules()
 {
 	local ns=$1
 	local m=$2
 
+	local t
 	for t in iptables ip6tables; do
 		# just to debug: check we have multiple subflows connection requests
 		ip netns exec $ns $t -A OUTPUT -p tcp --syn -m mark --mark $m -j ACCEPT
@@ -31,12 +37,7 @@ add_mark_rules()
 
 init()
 {
-	rndh=$(printf %x $sec)-$(mktemp -u XXXXXX)
-
-	ns1="ns1-$rndh"
-	ns2="ns2-$rndh"
-	ns_sbox="ns_sbox-$rndh"
-
+	local netns
 	for netns in "$ns1" "$ns2" "$ns_sbox";do
 		ip netns add $netns || exit $ksft_skip
 		ip -net $netns link set lo up
@@ -45,6 +46,7 @@ init()
 		ip netns exec $netns sysctl -q net.ipv4.conf.default.rp_filter=0
 	done
 
+	local i
 	for i in `seq 1 4`; do
 		ip link add ns1eth$i netns "$ns1" type veth peer name ns2eth$i netns "$ns2"
 		ip -net "$ns1" addr add 10.0.$i.1/24 dev ns1eth$i
@@ -74,6 +76,7 @@ init()
 
 cleanup()
 {
+	local netns
 	for netns in "$ns1" "$ns2" "$ns_sbox"; do
 		ip netns del $netns
 	done
@@ -104,15 +107,17 @@ check_mark()
 	local ns=$1
 	local af=$2
 
-	tables=iptables
+	local tables=iptables
 
 	if [ $af -eq 6 ];then
 		tables=ip6tables
 	fi
 
+	local counters values
 	counters=$(ip netns exec $ns $tables -v -L OUTPUT | grep DROP)
 	values=${counters%DROP*}
 
+	local v
 	for v in $values; do
 		if [ $v -ne 0 ]; then
 			echo "FAIL: got $tables $values in ns $ns , not 0 - not all expected packets marked" 1>&2
@@ -132,9 +137,9 @@ print_file_err()
 
 check_transfer()
 {
-	in=$1
-	out=$2
-	what=$3
+	local in=$1
+	local out=$2
+	local what=$3
 
 	cmp "$in" "$out" > /dev/null 2>&1
 	if [ $? -ne 0 ] ;then
@@ -157,18 +162,18 @@ is_v6()
 
 do_transfer()
 {
-	listener_ns="$1"
-	connector_ns="$2"
-	cl_proto="$3"
-	srv_proto="$4"
-	connect_addr="$5"
+	local listener_ns="$1"
+	local connector_ns="$2"
+	local cl_proto="$3"
+	local srv_proto="$4"
+	local connect_addr="$5"
 
-	port=12001
+	local port=12001
 
 	:> "$cout"
 	:> "$sout"
 
-	mptcp_connect="./mptcp_connect -r 20"
+	local mptcp_connect="./mptcp_connect -r 20"
 
 	local local_addr
 	if is_v6 "${connect_addr}"; then
@@ -181,7 +186,7 @@ do_transfer()
 		ip netns exec ${listener_ns} \
 			$mptcp_connect -t ${timeout_poll} -l -M 1 -p $port -s ${srv_proto} -c TIMESTAMPNS,TCPINQ \
 				${local_addr} < "$sin" > "$sout" &
-	spid=$!
+	local spid=$!
 
 	sleep 1
 
@@ -190,12 +195,12 @@ do_transfer()
 			$mptcp_connect -t ${timeout_poll} -M 2 -p $port -s ${cl_proto} -c TIMESTAMPNS,TCPINQ \
 				$connect_addr < "$cin" > "$cout" &
 
-	cpid=$!
+	local cpid=$!
 
 	wait $cpid
-	retc=$?
+	local retc=$?
 	wait $spid
-	rets=$?
+	local rets=$?
 
 	if [ ${rets} -ne 0 ] || [ ${retc} -ne 0 ]; then
 		echo " client exit code $retc, server $rets" 1>&2
@@ -230,9 +235,9 @@ do_transfer()
 
 make_file()
 {
-	name=$1
-	who=$2
-	size=$3
+	local name=$1
+	local who=$2
+	local size=$3
 
 	dd if=/dev/urandom of="$name" bs=1024 count=$size 2> /dev/null
 	echo -e "\nMPTCP_TEST_FILE_END_MARKER" >> "$name"
@@ -265,9 +270,9 @@ do_mptcp_sockopt_tests()
 
 run_tests()
 {
-	listener_ns="$1"
-	connector_ns="$2"
-	connect_addr="$3"
+	local listener_ns="$1"
+	local connector_ns="$2"
+	local connect_addr="$3"
 	local lret=0
 
 	do_transfer ${listener_ns} ${connector_ns} MPTCP MPTCP ${connect_addr}
@@ -282,8 +287,8 @@ run_tests()
 
 do_tcpinq_test()
 {
-	ip netns exec "$ns1" ./mptcp_inq "$@"
-	lret=$?
+	ip netns exec "$ns_sbox" ./mptcp_inq "$@"
+	local lret=$?
 	if [ $lret -ne 0 ];then
 		ret=$lret
 		echo "FAIL: mptcp_inq $@" 1>&2
@@ -298,9 +303,7 @@ do_tcpinq_tests()
 {
 	local lret=0
 
-	ip netns exec "$ns1" iptables -F
-	ip netns exec "$ns1" ip6tables -F
-
+	local args
 	for args in "-t tcp" "-r tcp"; do
 		do_tcpinq_test $args
 		lret=$?

tools/testing/selftests/net/mptcp/simult_flows.sh

 #!/bin/bash
 # SPDX-License-Identifier: GPL-2.0
 
+sec=$(date +%s)
 rndh=$(printf %x $sec)-$(mktemp -u XXXXXX)
 ns1="ns1-$rndh"
 ns2="ns2-$rndh"
@@ -148,9 +149,6 @@ do_transfer()
 	:> "$sout"
 	:> "$capout"
 
-	local addr_port
-	addr_port=$(printf "%s:%d" ${connect_addr} ${port})
-
 	if $capture; then
 		local capuser
 		if [ -z $SUDO_USER ] ; then

tools/testing/selftests/net/mptcp/userspace_pm.sh

@@ -11,11 +11,17 @@ ANNOUNCED=6        # MPTCP_EVENT_ANNOUNCED
 REMOVED=7          # MPTCP_EVENT_REMOVED
 SUB_ESTABLISHED=10 # MPTCP_EVENT_SUB_ESTABLISHED
 SUB_CLOSED=11      # MPTCP_EVENT_SUB_CLOSED
+LISTENER_CREATED=15 #MPTCP_EVENT_LISTENER_CREATED
+LISTENER_CLOSED=16  #MPTCP_EVENT_LISTENER_CLOSED
 
 AF_INET=2
 AF_INET6=10
 
-evts_pid=0
+file=""
+server_evts=""
+client_evts=""
+server_evts_pid=0
+client_evts_pid=0
 client4_pid=0
 server4_pid=0
 client6_pid=0
@@ -33,7 +39,7 @@ client_addr_id=${RANDOM:0:2}
 server_addr_id=${RANDOM:0:2}
 
 sec=$(date +%s)
-rndh=$(stdbuf -o0 -e0 printf %x "$sec")-$(mktemp -u XXXXXX)
+rndh=$(printf %x "$sec")-$(mktemp -u XXXXXX)
 ns1="ns1-$rndh"
 ns2="ns2-$rndh"
 
@@ -47,7 +53,7 @@ cleanup()
 {
 	echo "cleanup"
 
-	rm -rf $file
+	rm -rf $file $client_evts $server_evts
 
 	# Terminate the MPTCP connection and related processes
 	if [ $client4_pid -ne 0 ]; then
@@ -62,8 +68,11 @@ cleanup()
 	if [ $server6_pid -ne 0 ]; then
 		kill_wait $server6_pid
 	fi
-	if [ $evts_pid -ne 0 ]; then
-		kill_wait $evts_pid
+	if [ $server_evts_pid -ne 0 ]; then
+		kill_wait $server_evts_pid
+	fi
+	if [ $client_evts_pid -ne 0 ]; then
+		kill_wait $client_evts_pid
 	fi
 	local netns
 	for netns in "$ns1" "$ns2" ;do
@@ -113,8 +122,9 @@ make_file()
 
 make_connection()
 {
-	local file
+	if [ -z "$file" ]; then
 		file=$(mktemp)
+	fi
 	make_file "$file" "client"
 
 	local is_v6=$1
@@ -132,16 +142,24 @@ make_connection()
 
 	# Capture netlink events over the two network namespaces running
 	# the MPTCP client and server
-	local client_evts
+	if [ -z "$client_evts" ]; then
 		client_evts=$(mktemp)
+	fi
 	:>"$client_evts"
+	if [ $client_evts_pid -ne 0 ]; then
+		kill_wait $client_evts_pid
+	fi
 	ip netns exec "$ns2" ./pm_nl_ctl events >> "$client_evts" 2>&1 &
-	local client_evts_pid=$!
-	local server_evts
+	client_evts_pid=$!
+	if [ -z "$server_evts" ]; then
 		server_evts=$(mktemp)
+	fi
 	:>"$server_evts"
+	if [ $server_evts_pid -ne 0 ]; then
+		kill_wait $server_evts_pid
+	fi
 	ip netns exec "$ns1" ./pm_nl_ctl events >> "$server_evts" 2>&1 &
-	local server_evts_pid=$!
+	server_evts_pid=$!
 	sleep 0.5
 
 	# Run the server
@@ -159,7 +177,6 @@ make_connection()
 	sleep 1
 
 	# Capture client/server attributes from MPTCP connection netlink events
-	kill_wait $client_evts_pid
 
 	local client_token
 	local client_port
@@ -171,11 +188,10 @@ make_connection()
 	client_port=$(sed --unbuffered -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q' "$client_evts")
 	client_serverside=$(sed --unbuffered -n 's/.*\(server_side:\)\([[:digit:]]*\).*$/\2/p;q'\
 				      "$client_evts")
-	kill_wait $server_evts_pid
-	server_token=$(sed --unbuffered -n 's/.*\(token:\)\([[:digit:]]*\).*$/\2/p;q' "$server_evts")
-	server_serverside=$(sed --unbuffered -n 's/.*\(server_side:\)\([[:digit:]]*\).*$/\2/p;q'\
-				      "$server_evts")
-	rm -f "$client_evts" "$server_evts" "$file"
+	server_token=$(grep "type:1," "$server_evts" |
+		       sed --unbuffered -n 's/.*\(token:\)\([[:digit:]]*\).*$/\2/p;q')
+	server_serverside=$(grep "type:1," "$server_evts" |
+			    sed --unbuffered -n 's/.*\(server_side:\)\([[:digit:]]*\).*$/\2/p;q')
 
 	if [ "$client_token" != "" ] && [ "$server_token" != "" ] && [ "$client_serverside" = 0 ] &&
 		   [ "$server_serverside" = 1 ]
@@ -239,13 +255,8 @@ verify_announce_event()
 
 test_announce()
 {
-	local evts
-	evts=$(mktemp)
 	# Capture events on the network namespace running the server
-	:>"$evts"
-	ip netns exec "$ns1" ./pm_nl_ctl events >> "$evts" 2>&1 &
-	evts_pid=$!
-	sleep 0.5
+	:>"$server_evts"
 
 	# ADD_ADDR using an invalid token should result in no action
 	local invalid_token=$(( client4_token - 1))
@@ -253,7 +264,7 @@ test_announce()
 	   $client_addr_id dev ns2eth1 > /dev/null 2>&1
 
 	local type
-	type=$(sed --unbuffered -n 's/.*\(type:\)\([[:digit:]]*\).*$/\2/p;q' "$evts")
+	type=$(sed --unbuffered -n 's/.*\(type:\)\([[:digit:]]*\).*$/\2/p;q' "$server_evts")
 	stdbuf -o0 -e0 printf "ADD_ADDR 10.0.2.2 (ns2) => ns1, invalid token    \t\t"
 	if [ "$type" = "" ]
 	then
@@ -264,71 +275,63 @@ test_announce()
 	fi
 
 	# ADD_ADDR from the client to server machine reusing the subflow port
-	:>"$evts"
+	:>"$server_evts"
 	ip netns exec "$ns2"\
 	   ./pm_nl_ctl ann 10.0.2.2 token "$client4_token" id $client_addr_id dev\
 	   ns2eth1 > /dev/null 2>&1
 	stdbuf -o0 -e0 printf "ADD_ADDR id:%d 10.0.2.2 (ns2) => ns1, reuse port \t\t" $client_addr_id
 	sleep 0.5
-	verify_announce_event "$evts" "$ANNOUNCED" "$server4_token" "10.0.2.2" "$client_addr_id"\
+	verify_announce_event $server_evts $ANNOUNCED $server4_token "10.0.2.2" $client_addr_id \
 			      "$client4_port"
 
 	# ADD_ADDR6 from the client to server machine reusing the subflow port
-	:>"$evts"
+	:>"$server_evts"
 	ip netns exec "$ns2" ./pm_nl_ctl ann\
 	   dead:beef:2::2 token "$client6_token" id $client_addr_id dev ns2eth1 > /dev/null 2>&1
 	stdbuf -o0 -e0 printf "ADD_ADDR6 id:%d dead:beef:2::2 (ns2) => ns1, reuse port\t\t" $client_addr_id
 	sleep 0.5
-	verify_announce_event "$evts" "$ANNOUNCED" "$server6_token" "dead:beef:2::2"\
+	verify_announce_event "$server_evts" "$ANNOUNCED" "$server6_token" "dead:beef:2::2"\
 			      "$client_addr_id" "$client6_port" "v6"
 
 	# ADD_ADDR from the client to server machine using a new port
-	:>"$evts"
+	:>"$server_evts"
 	client_addr_id=$((client_addr_id+1))
 	ip netns exec "$ns2" ./pm_nl_ctl ann 10.0.2.2 token "$client4_token" id\
 	   $client_addr_id dev ns2eth1 port $new4_port > /dev/null 2>&1
 	stdbuf -o0 -e0 printf "ADD_ADDR id:%d 10.0.2.2 (ns2) => ns1, new port \t\t\t" $client_addr_id
 	sleep 0.5
-	verify_announce_event "$evts" "$ANNOUNCED" "$server4_token" "10.0.2.2"\
+	verify_announce_event "$server_evts" "$ANNOUNCED" "$server4_token" "10.0.2.2"\
 			      "$client_addr_id" "$new4_port"
 
-	kill_wait $evts_pid
-
 	# Capture events on the network namespace running the client
-	:>"$evts"
-	ip netns exec "$ns2" ./pm_nl_ctl events >> "$evts" 2>&1 &
-	evts_pid=$!
-	sleep 0.5
+	:>"$client_evts"
 
 	# ADD_ADDR from the server to client machine reusing the subflow port
 	ip netns exec "$ns1" ./pm_nl_ctl ann 10.0.2.1 token "$server4_token" id\
 	   $server_addr_id dev ns1eth2 > /dev/null 2>&1
 	stdbuf -o0 -e0 printf "ADD_ADDR id:%d 10.0.2.1 (ns1) => ns2, reuse port \t\t" $server_addr_id
 	sleep 0.5
-	verify_announce_event "$evts" "$ANNOUNCED" "$client4_token" "10.0.2.1"\
+	verify_announce_event "$client_evts" "$ANNOUNCED" "$client4_token" "10.0.2.1"\
 			      "$server_addr_id" "$app4_port"
 
 	# ADD_ADDR6 from the server to client machine reusing the subflow port
-	:>"$evts"
+	:>"$client_evts"
 	ip netns exec "$ns1" ./pm_nl_ctl ann dead:beef:2::1 token "$server6_token" id\
 	   $server_addr_id dev ns1eth2 > /dev/null 2>&1
 	stdbuf -o0 -e0 printf "ADD_ADDR6 id:%d dead:beef:2::1 (ns1) => ns2, reuse port\t\t" $server_addr_id
 	sleep 0.5
-	verify_announce_event "$evts" "$ANNOUNCED" "$client6_token" "dead:beef:2::1"\
+	verify_announce_event "$client_evts" "$ANNOUNCED" "$client6_token" "dead:beef:2::1"\
 			      "$server_addr_id" "$app6_port" "v6"
 
 	# ADD_ADDR from the server to client machine using a new port
-	:>"$evts"
+	:>"$client_evts"
 	server_addr_id=$((server_addr_id+1))
 	ip netns exec "$ns1" ./pm_nl_ctl ann 10.0.2.1 token "$server4_token" id\
 	   $server_addr_id dev ns1eth2 port $new4_port > /dev/null 2>&1
 	stdbuf -o0 -e0 printf "ADD_ADDR id:%d 10.0.2.1 (ns1) => ns2, new port \t\t\t" $server_addr_id
 	sleep 0.5
-	verify_announce_event "$evts" "$ANNOUNCED" "$client4_token" "10.0.2.1"\
+	verify_announce_event "$client_evts" "$ANNOUNCED" "$client4_token" "10.0.2.1"\
 			      "$server_addr_id" "$new4_port"
-
-	kill_wait $evts_pid
-	rm -f "$evts"
 }
 
 verify_remove_event()
@@ -356,14 +359,8 @@ verify_remove_event()
 
 test_remove()
 {
-	local evts
-	evts=$(mktemp)
-
 	# Capture events on the network namespace running the server
-	:>"$evts"
-	ip netns exec "$ns1" ./pm_nl_ctl events >> "$evts" 2>&1 &
-	evts_pid=$!
-	sleep 0.5
+	:>"$server_evts"
 
 	# RM_ADDR using an invalid token should result in no action
 	local invalid_token=$(( client4_token - 1 ))
@@ -372,7 +369,7 @@ test_remove()
 	stdbuf -o0 -e0 printf "RM_ADDR id:%d ns2 => ns1, invalid token                    \t"\
 	       $client_addr_id
 	local type
-	type=$(sed --unbuffered -n 's/.*\(type:\)\([[:digit:]]*\).*$/\2/p;q' "$evts")
+	type=$(sed --unbuffered -n 's/.*\(type:\)\([[:digit:]]*\).*$/\2/p;q' "$server_evts")
 	if [ "$type" = "" ]
 	then
 		stdbuf -o0 -e0 printf "[OK]\n"
@@ -386,7 +383,7 @@ test_remove()
 	   $invalid_id > /dev/null 2>&1
 	stdbuf -o0 -e0 printf "RM_ADDR id:%d ns2 => ns1, invalid id                    \t"\
 	       $invalid_id
-	type=$(sed --unbuffered -n 's/.*\(type:\)\([[:digit:]]*\).*$/\2/p;q' "$evts")
+	type=$(sed --unbuffered -n 's/.*\(type:\)\([[:digit:]]*\).*$/\2/p;q' "$server_evts")
 	if [ "$type" = "" ]
 	then
 		stdbuf -o0 -e0 printf "[OK]\n"
@@ -395,40 +392,35 @@ test_remove()
 	fi
 
 	# RM_ADDR from the client to server machine
-	:>"$evts"
+	:>"$server_evts"
 	ip netns exec "$ns2" ./pm_nl_ctl rem token "$client4_token" id\
 	   $client_addr_id > /dev/null 2>&1
 	stdbuf -o0 -e0 printf "RM_ADDR id:%d ns2 => ns1                                \t"\
 	       $client_addr_id
 	sleep 0.5
-	verify_remove_event "$evts" "$REMOVED" "$server4_token" "$client_addr_id"
+	verify_remove_event "$server_evts" "$REMOVED" "$server4_token" "$client_addr_id"
 
 	# RM_ADDR from the client to server machine
-	:>"$evts"
+	:>"$server_evts"
 	client_addr_id=$(( client_addr_id - 1 ))
 	ip netns exec "$ns2" ./pm_nl_ctl rem token "$client4_token" id\
 	   $client_addr_id > /dev/null 2>&1
 	stdbuf -o0 -e0 printf "RM_ADDR id:%d ns2 => ns1                                \t"\
 	       $client_addr_id
 	sleep 0.5
-	verify_remove_event "$evts" "$REMOVED" "$server4_token" "$client_addr_id"
+	verify_remove_event "$server_evts" "$REMOVED" "$server4_token" "$client_addr_id"
 
 	# RM_ADDR6 from the client to server machine
-	:>"$evts"
+	:>"$server_evts"
 	ip netns exec "$ns2" ./pm_nl_ctl rem token "$client6_token" id\
 	   $client_addr_id > /dev/null 2>&1
 	stdbuf -o0 -e0 printf "RM_ADDR6 id:%d ns2 => ns1                               \t"\
 	       $client_addr_id
 	sleep 0.5
-	verify_remove_event "$evts" "$REMOVED" "$server6_token" "$client_addr_id"
-
-	kill_wait $evts_pid
+	verify_remove_event "$server_evts" "$REMOVED" "$server6_token" "$client_addr_id"
 
 	# Capture events on the network namespace running the client
-	:>"$evts"
-	ip netns exec "$ns2" ./pm_nl_ctl events >> "$evts" 2>&1 &
-	evts_pid=$!
-	sleep 0.5
+	:>"$client_evts"
 
 	# RM_ADDR from the server to client machine
 	ip netns exec "$ns1" ./pm_nl_ctl rem token "$server4_token" id\
@@ -436,27 +428,24 @@ test_remove()
 	stdbuf -o0 -e0 printf "RM_ADDR id:%d ns1 => ns2                                \t"\
 	       $server_addr_id
 	sleep 0.5
-	verify_remove_event "$evts" "$REMOVED" "$client4_token" "$server_addr_id"
+	verify_remove_event "$client_evts" "$REMOVED" "$client4_token" "$server_addr_id"
 
 	# RM_ADDR from the server to client machine
-	:>"$evts"
+	:>"$client_evts"
 	server_addr_id=$(( server_addr_id - 1 ))
 	ip netns exec "$ns1" ./pm_nl_ctl rem token "$server4_token" id\
 	   $server_addr_id > /dev/null 2>&1
 	stdbuf -o0 -e0 printf "RM_ADDR id:%d ns1 => ns2                                \t" $server_addr_id
 	sleep 0.5
-	verify_remove_event "$evts" "$REMOVED" "$client4_token" "$server_addr_id"
+	verify_remove_event "$client_evts" "$REMOVED" "$client4_token" "$server_addr_id"
 
 	# RM_ADDR6 from the server to client machine
-	:>"$evts"
+	:>"$client_evts"
 	ip netns exec "$ns1" ./pm_nl_ctl rem token "$server6_token" id\
 	   $server_addr_id > /dev/null 2>&1
 	stdbuf -o0 -e0 printf "RM_ADDR6 id:%d ns1 => ns2                               \t" $server_addr_id
 	sleep 0.5
-	verify_remove_event "$evts" "$REMOVED" "$client6_token" "$server_addr_id"
-
-	kill_wait $evts_pid
-	rm -f "$evts"
+	verify_remove_event "$client_evts" "$REMOVED" "$client6_token" "$server_addr_id"
 }
 
 verify_subflow_events()
@@ -532,13 +521,8 @@ verify_subflow_events()
 
 test_subflows()
 {
-	local evts
-	evts=$(mktemp)
 	# Capture events on the network namespace running the server
-	:>"$evts"
-	ip netns exec "$ns1" ./pm_nl_ctl events >> "$evts" 2>&1 &
-	evts_pid=$!
-	sleep 0.5
+	:>"$server_evts"
 
 	# Attempt to add a listener at 10.0.2.2:<subflow-port>
 	ip netns exec "$ns2" ./pm_nl_ctl listen 10.0.2.2\
@@ -551,25 +535,25 @@ test_subflows()
 	sleep 0.5
 
 	# CREATE_SUBFLOW from server to client machine
-	:>"$evts"
+	:>"$server_evts"
 	ip netns exec "$ns1" ./pm_nl_ctl csf lip 10.0.2.1 lid 23 rip 10.0.2.2\
 	   rport "$client4_port" token "$server4_token" > /dev/null 2>&1
 	sleep 0.5
-	verify_subflow_events "$evts" "$SUB_ESTABLISHED" "$server4_token" "$AF_INET" "10.0.2.1"\
+	verify_subflow_events $server_evts $SUB_ESTABLISHED $server4_token $AF_INET "10.0.2.1" \
 			      "10.0.2.2" "$client4_port" "23" "$client_addr_id" "ns1" "ns2"
 
 	# Delete the listener from the client ns, if one was created
 	kill_wait $listener_pid
 
 	local sport
-	sport=$(sed --unbuffered -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q' "$evts")
+	sport=$(sed --unbuffered -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q' "$server_evts")
 
 	# DESTROY_SUBFLOW from server to client machine
-	:>"$evts"
+	:>"$server_evts"
 	ip netns exec "$ns1" ./pm_nl_ctl dsf lip 10.0.2.1 lport "$sport" rip 10.0.2.2 rport\
 	   "$client4_port" token "$server4_token" > /dev/null 2>&1
 	sleep 0.5
-	verify_subflow_events "$evts" "$SUB_CLOSED" "$server4_token" "$AF_INET" "10.0.2.1"\
+	verify_subflow_events "$server_evts" "$SUB_CLOSED" "$server4_token" "$AF_INET" "10.0.2.1"\
 			      "10.0.2.2" "$client4_port" "23" "$client_addr_id" "ns1" "ns2"
 
 	# RM_ADDR from client to server machine
@@ -583,31 +567,31 @@ test_subflows()
 	listener_pid=$!
 
 	# ADD_ADDR6 from client to server machine reusing the subflow port
-	:>"$evts"
+	:>"$server_evts"
 	ip netns exec "$ns2" ./pm_nl_ctl ann dead:beef:2::2 token "$client6_token" id\
 	   $client_addr_id > /dev/null 2>&1
 	sleep 0.5
 
 	# CREATE_SUBFLOW6 from server to client machine
-	:>"$evts"
+	:>"$server_evts"
 	ip netns exec "$ns1" ./pm_nl_ctl csf lip dead:beef:2::1 lid 23 rip\
 	   dead:beef:2::2 rport "$client6_port" token "$server6_token" > /dev/null 2>&1
 	sleep 0.5
-	verify_subflow_events "$evts" "$SUB_ESTABLISHED" "$server6_token" "$AF_INET6"\
+	verify_subflow_events "$server_evts" "$SUB_ESTABLISHED" "$server6_token" "$AF_INET6"\
 			      "dead:beef:2::1" "dead:beef:2::2" "$client6_port" "23"\
 			      "$client_addr_id" "ns1" "ns2"
 
 	# Delete the listener from the client ns, if one was created
 	kill_wait $listener_pid
 
-	sport=$(sed --unbuffered -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q' "$evts")
+	sport=$(sed --unbuffered -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q' "$server_evts")
 
 	# DESTROY_SUBFLOW6 from server to client machine
-	:>"$evts"
+	:>"$server_evts"
 	ip netns exec "$ns1" ./pm_nl_ctl dsf lip dead:beef:2::1 lport "$sport" rip\
 	   dead:beef:2::2 rport "$client6_port" token "$server6_token" > /dev/null 2>&1
 	sleep 0.5
-	verify_subflow_events "$evts" "$SUB_CLOSED" "$server6_token" "$AF_INET6"\
+	verify_subflow_events "$server_evts" "$SUB_CLOSED" "$server6_token" "$AF_INET6"\
 			      "dead:beef:2::1" "dead:beef:2::2" "$client6_port" "23"\
 			      "$client_addr_id" "ns1" "ns2"
 
@@ -622,44 +606,39 @@ test_subflows()
 	listener_pid=$!
 
 	# ADD_ADDR from client to server machine using a new port
-	:>"$evts"
+	:>"$server_evts"
 	ip netns exec "$ns2" ./pm_nl_ctl ann 10.0.2.2 token "$client4_token" id\
 	   $client_addr_id port $new4_port > /dev/null 2>&1
 	sleep 0.5
 
 	# CREATE_SUBFLOW from server to client machine
-	:>"$evts"
+	:>"$server_evts"
 	ip netns exec "$ns1" ./pm_nl_ctl csf lip 10.0.2.1 lid 23 rip 10.0.2.2 rport\
 	   $new4_port token "$server4_token" > /dev/null 2>&1
 	sleep 0.5
-	verify_subflow_events "$evts" "$SUB_ESTABLISHED" "$server4_token" "$AF_INET"\
+	verify_subflow_events "$server_evts" "$SUB_ESTABLISHED" "$server4_token" "$AF_INET"\
 			      "10.0.2.1" "10.0.2.2" "$new4_port" "23"\
 			      "$client_addr_id" "ns1" "ns2"
 
 	# Delete the listener from the client ns, if one was created
 	kill_wait $listener_pid
 
-	sport=$(sed --unbuffered -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q' "$evts")
+	sport=$(sed --unbuffered -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q' "$server_evts")
 
 	# DESTROY_SUBFLOW from server to client machine
-	:>"$evts"
+	:>"$server_evts"
 	ip netns exec "$ns1" ./pm_nl_ctl dsf lip 10.0.2.1 lport "$sport" rip 10.0.2.2 rport\
 	   $new4_port token "$server4_token" > /dev/null 2>&1
 	sleep 0.5
-	verify_subflow_events "$evts" "$SUB_CLOSED" "$server4_token" "$AF_INET" "10.0.2.1"\
+	verify_subflow_events "$server_evts" "$SUB_CLOSED" "$server4_token" "$AF_INET" "10.0.2.1"\
 			      "10.0.2.2" "$new4_port" "23" "$client_addr_id" "ns1" "ns2"
 
 	# RM_ADDR from client to server machine
 	ip netns exec "$ns2" ./pm_nl_ctl rem id $client_addr_id token\
 	   "$client4_token" > /dev/null 2>&1
 
-	kill_wait $evts_pid
-
 	# Capture events on the network namespace running the client
-	:>"$evts"
-	ip netns exec "$ns2" ./pm_nl_ctl events >> "$evts" 2>&1 &
-	evts_pid=$!
-	sleep 0.5
+	:>"$client_evts"
 
 	# Attempt to add a listener at 10.0.2.1:<subflow-port>
 	ip netns exec "$ns1" ./pm_nl_ctl listen 10.0.2.1\
@@ -672,24 +651,24 @@ test_subflows()
 	sleep 0.5
 
 	# CREATE_SUBFLOW from client to server machine
-	:>"$evts"
+	:>"$client_evts"
 	ip netns exec "$ns2" ./pm_nl_ctl csf lip 10.0.2.2 lid 23 rip 10.0.2.1 rport\
 	   $app4_port token "$client4_token" > /dev/null 2>&1
 	sleep 0.5
-	verify_subflow_events "$evts" "$SUB_ESTABLISHED" "$client4_token" "$AF_INET" "10.0.2.2"\
+	verify_subflow_events $client_evts $SUB_ESTABLISHED $client4_token $AF_INET "10.0.2.2"\
 			      "10.0.2.1" "$app4_port" "23" "$server_addr_id" "ns2" "ns1"
 
 	# Delete the listener from the server ns, if one was created
 	kill_wait $listener_pid
 
-	sport=$(sed --unbuffered -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q' "$evts")
+	sport=$(sed --unbuffered -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q' "$client_evts")
 
 	# DESTROY_SUBFLOW from client to server machine
-	:>"$evts"
+	:>"$client_evts"
 	ip netns exec "$ns2" ./pm_nl_ctl dsf lip 10.0.2.2 lport "$sport" rip 10.0.2.1 rport\
 	   $app4_port token "$client4_token" > /dev/null 2>&1
 	sleep 0.5
-	verify_subflow_events "$evts" "$SUB_CLOSED" "$client4_token" "$AF_INET" "10.0.2.2"\
+	verify_subflow_events "$client_evts" "$SUB_CLOSED" "$client4_token" "$AF_INET" "10.0.2.2"\
 			      "10.0.2.1" "$app4_port" "23" "$server_addr_id" "ns2" "ns1"
 
 	# RM_ADDR from server to client machine
@@ -703,17 +682,17 @@ test_subflows()
 	listener_pid=$!
 
 	# ADD_ADDR6 from server to client machine reusing the subflow port
-	:>"$evts"
+	:>"$client_evts"
 	ip netns exec "$ns1" ./pm_nl_ctl ann dead:beef:2::1 token "$server6_token" id\
 	   $server_addr_id > /dev/null 2>&1
 	sleep 0.5
 
 	# CREATE_SUBFLOW6 from client to server machine
-	:>"$evts"
+	:>"$client_evts"
 	ip netns exec "$ns2" ./pm_nl_ctl csf lip dead:beef:2::2 lid 23 rip\
 	   dead:beef:2::1 rport $app6_port token "$client6_token" > /dev/null 2>&1
 	sleep 0.5
-	verify_subflow_events "$evts" "$SUB_ESTABLISHED" "$client6_token"\
+	verify_subflow_events "$client_evts" "$SUB_ESTABLISHED" "$client6_token"\
 			      "$AF_INET6" "dead:beef:2::2"\
 			      "dead:beef:2::1" "$app6_port" "23"\
 			      "$server_addr_id" "ns2" "ns1"
@@ -721,14 +700,14 @@ test_subflows()
 	# Delete the listener from the server ns, if one was created
 	kill_wait $listener_pid
 
-	sport=$(sed --unbuffered -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q' "$evts")
+	sport=$(sed --unbuffered -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q' "$client_evts")
 
 	# DESTROY_SUBFLOW6 from client to server machine
-	:>"$evts"
+	:>"$client_evts"
 	ip netns exec "$ns2" ./pm_nl_ctl dsf lip dead:beef:2::2 lport "$sport" rip\
 	   dead:beef:2::1 rport $app6_port token "$client6_token" > /dev/null 2>&1
 	sleep 0.5
-	verify_subflow_events "$evts" "$SUB_CLOSED" "$client6_token" "$AF_INET6" "dead:beef:2::2"\
+	verify_subflow_events $client_evts $SUB_CLOSED $client6_token $AF_INET6 "dead:beef:2::2"\
 			      "dead:beef:2::1" "$app6_port" "23" "$server_addr_id" "ns2" "ns1"
 
 	# RM_ADDR6 from server to client machine
@@ -742,38 +721,35 @@ test_subflows()
 	listener_pid=$!
 
 	# ADD_ADDR from server to client machine using a new port
-	:>"$evts"
+	:>"$client_evts"
 	ip netns exec "$ns1" ./pm_nl_ctl ann 10.0.2.1 token "$server4_token" id\
 	   $server_addr_id port $new4_port > /dev/null 2>&1
 	sleep 0.5
 
 	# CREATE_SUBFLOW from client to server machine
-	:>"$evts"
+	:>"$client_evts"
 	ip netns exec "$ns2" ./pm_nl_ctl csf lip 10.0.2.2 lid 23 rip 10.0.2.1 rport\
 	   $new4_port token "$client4_token" > /dev/null 2>&1
 	sleep 0.5
-	verify_subflow_events "$evts" "$SUB_ESTABLISHED" "$client4_token" "$AF_INET"\
+	verify_subflow_events "$client_evts" "$SUB_ESTABLISHED" "$client4_token" "$AF_INET"\
 			      "10.0.2.2" "10.0.2.1" "$new4_port" "23" "$server_addr_id" "ns2" "ns1"
 
 	# Delete the listener from the server ns, if one was created
 	kill_wait $listener_pid
 
-	sport=$(sed --unbuffered -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q' "$evts")
+	sport=$(sed --unbuffered -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q' "$client_evts")
 
 	# DESTROY_SUBFLOW from client to server machine
-	:>"$evts"
+	:>"$client_evts"
 	ip netns exec "$ns2" ./pm_nl_ctl dsf lip 10.0.2.2 lport "$sport" rip 10.0.2.1 rport\
 	   $new4_port token "$client4_token" > /dev/null 2>&1
 	sleep 0.5
-	verify_subflow_events "$evts" "$SUB_CLOSED" "$client4_token" "$AF_INET" "10.0.2.2"\
+	verify_subflow_events "$client_evts" "$SUB_CLOSED" "$client4_token" "$AF_INET" "10.0.2.2"\
 			      "10.0.2.1" "$new4_port" "23" "$server_addr_id" "ns2" "ns1"
 
 	# RM_ADDR from server to client machine
 	ip netns exec "$ns1" ./pm_nl_ctl rem id $server_addr_id token\
 	   "$server4_token" > /dev/null 2>&1
-
-	kill_wait $evts_pid
-	rm -f "$evts"
 }
 
 test_prio()
@@ -807,11 +783,85 @@ test_prio()
 	fi
 }
 
+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
+
+	if [ $e_type = $LISTENER_CREATED ]; then
+		stdbuf -o0 -e0 printf "CREATE_LISTENER %s:%s\t\t\t\t\t"\
+			$e_saddr $e_sport
+	elif [ $e_type = $LISTENER_CLOSED ]; then
+		stdbuf -o0 -e0 printf "CLOSE_LISTENER %s:%s\t\t\t\t\t"\
+			$e_saddr $e_sport
+	fi
+
+	type=$(grep "type:$e_type," $evt |
+	       sed --unbuffered -n 's/.*\(type:\)\([[:digit:]]*\).*$/\2/p;q')
+	family=$(grep "type:$e_type," $evt |
+		 sed --unbuffered -n 's/.*\(family:\)\([[:digit:]]*\).*$/\2/p;q')
+	sport=$(grep "type:$e_type," $evt |
+		sed --unbuffered -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q')
+	if [ $family ] && [ $family = $AF_INET6 ]; then
+		saddr=$(grep "type:$e_type," $evt |
+			sed --unbuffered -n 's/.*\(saddr6:\)\([0-9a-f:.]*\).*$/\2/p;q')
+	else
+		saddr=$(grep "type:$e_type," $evt |
+			sed --unbuffered -n 's/.*\(saddr4:\)\([0-9.]*\).*$/\2/p;q')
+	fi
+
+	if [ $type ] && [ $type = $e_type ] &&
+	   [ $family ] && [ $family = $e_family ] &&
+	   [ $saddr ] && [ $saddr = $e_saddr ] &&
+	   [ $sport ] && [ $sport = $e_sport ]; then
+		stdbuf -o0 -e0 printf "[OK]\n"
+		return 0
+	fi
+	stdbuf -o0 -e0 printf "[FAIL]\n"
+	exit 1
+}
+
+test_listener()
+{
+	# Capture events on the network namespace running the client
+	:>$client_evts
+
+	# Attempt to add a listener at 10.0.2.2:<subflow-port>
+	ip netns exec $ns2 ./pm_nl_ctl listen 10.0.2.2\
+		$client4_port > /dev/null 2>&1 &
+	local listener_pid=$!
+
+	verify_listener_events $client_evts $LISTENER_CREATED $AF_INET 10.0.2.2 $client4_port
+
+	# ADD_ADDR from client to server machine reusing the subflow port
+	ip netns exec $ns2 ./pm_nl_ctl ann 10.0.2.2 token $client4_token id\
+		$client_addr_id > /dev/null 2>&1
+	sleep 0.5
+
+	# CREATE_SUBFLOW from server to client machine
+	ip netns exec $ns1 ./pm_nl_ctl csf lip 10.0.2.1 lid 23 rip 10.0.2.2\
+		rport $client4_port token $server4_token > /dev/null 2>&1
+	sleep 0.5
+
+	# Delete the listener from the client ns, if one was created
+	kill_wait $listener_pid
+
+	verify_listener_events $client_evts $LISTENER_CLOSED $AF_INET 10.0.2.2 $client4_port
+}
+
 make_connection
 make_connection "v6"
 test_announce
 test_remove
 test_subflows
 test_prio
+test_listener
 
 exit 0