From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001
From: Daniel Baumann <daniel.baumann@progress-linux.org>
Date: Sun, 7 Apr 2024 20:49:45 +0200
Subject: Adding upstream version 6.1.76.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
---
 tools/testing/selftests/net/mptcp/.gitignore       |    6 +
 tools/testing/selftests/net/mptcp/Makefile         |   16 +
 tools/testing/selftests/net/mptcp/config           |   31 +
 tools/testing/selftests/net/mptcp/diag.sh          |  241 ++
 tools/testing/selftests/net/mptcp/mptcp_connect.c  | 1415 +++++++++
 tools/testing/selftests/net/mptcp/mptcp_connect.sh |  934 ++++++
 tools/testing/selftests/net/mptcp/mptcp_inq.c      |  599 ++++
 tools/testing/selftests/net/mptcp/mptcp_join.sh    | 3327 ++++++++++++++++++++
 tools/testing/selftests/net/mptcp/mptcp_lib.sh     |  104 +
 tools/testing/selftests/net/mptcp/mptcp_sockopt.c  |  752 +++++
 tools/testing/selftests/net/mptcp/mptcp_sockopt.sh |  367 +++
 tools/testing/selftests/net/mptcp/pm_netlink.sh    |  196 ++
 tools/testing/selftests/net/mptcp/pm_nl_ctl.c      | 1505 +++++++++
 tools/testing/selftests/net/mptcp/settings         |    1 +
 tools/testing/selftests/net/mptcp/simult_flows.sh  |  310 ++
 tools/testing/selftests/net/mptcp/userspace_pm.sh  |  886 ++++++
 16 files changed, 10690 insertions(+)
 create mode 100644 tools/testing/selftests/net/mptcp/.gitignore
 create mode 100644 tools/testing/selftests/net/mptcp/Makefile
 create mode 100644 tools/testing/selftests/net/mptcp/config
 create mode 100755 tools/testing/selftests/net/mptcp/diag.sh
 create mode 100644 tools/testing/selftests/net/mptcp/mptcp_connect.c
 create mode 100755 tools/testing/selftests/net/mptcp/mptcp_connect.sh
 create mode 100644 tools/testing/selftests/net/mptcp/mptcp_inq.c
 create mode 100755 tools/testing/selftests/net/mptcp/mptcp_join.sh
 create mode 100644 tools/testing/selftests/net/mptcp/mptcp_lib.sh
 create mode 100644 tools/testing/selftests/net/mptcp/mptcp_sockopt.c
 create mode 100755 tools/testing/selftests/net/mptcp/mptcp_sockopt.sh
 create mode 100755 tools/testing/selftests/net/mptcp/pm_netlink.sh
 create mode 100644 tools/testing/selftests/net/mptcp/pm_nl_ctl.c
 create mode 100644 tools/testing/selftests/net/mptcp/settings
 create mode 100755 tools/testing/selftests/net/mptcp/simult_flows.sh
 create mode 100755 tools/testing/selftests/net/mptcp/userspace_pm.sh

(limited to 'tools/testing/selftests/net/mptcp')

diff --git a/tools/testing/selftests/net/mptcp/.gitignore b/tools/testing/selftests/net/mptcp/.gitignore
new file mode 100644
index 000000000..49daae73c
--- /dev/null
+++ b/tools/testing/selftests/net/mptcp/.gitignore
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0-only
+mptcp_connect
+mptcp_inq
+mptcp_sockopt
+pm_nl_ctl
+*.pcap
diff --git a/tools/testing/selftests/net/mptcp/Makefile b/tools/testing/selftests/net/mptcp/Makefile
new file mode 100644
index 000000000..7b936a926
--- /dev/null
+++ b/tools/testing/selftests/net/mptcp/Makefile
@@ -0,0 +1,16 @@
+# SPDX-License-Identifier: GPL-2.0
+
+top_srcdir = ../../../../..
+
+CFLAGS =  -Wall -Wl,--no-as-needed -O2 -g -I$(top_srcdir)/usr/include $(KHDR_INCLUDES)
+
+TEST_PROGS := mptcp_connect.sh pm_netlink.sh mptcp_join.sh diag.sh \
+	      simult_flows.sh mptcp_sockopt.sh userspace_pm.sh
+
+TEST_GEN_FILES = mptcp_connect pm_nl_ctl mptcp_sockopt mptcp_inq
+
+TEST_FILES := mptcp_lib.sh settings
+
+EXTRA_CLEAN := *.pcap
+
+include ../../lib.mk
diff --git a/tools/testing/selftests/net/mptcp/config b/tools/testing/selftests/net/mptcp/config
new file mode 100644
index 000000000..e317c2e44
--- /dev/null
+++ b/tools/testing/selftests/net/mptcp/config
@@ -0,0 +1,31 @@
+CONFIG_KALLSYMS=y
+CONFIG_MPTCP=y
+CONFIG_IPV6=y
+CONFIG_MPTCP_IPV6=y
+CONFIG_INET_DIAG=m
+CONFIG_INET_MPTCP_DIAG=m
+CONFIG_VETH=y
+CONFIG_NET_SCH_NETEM=m
+CONFIG_SYN_COOKIES=y
+CONFIG_NETFILTER=y
+CONFIG_NETFILTER_ADVANCED=y
+CONFIG_NETFILTER_NETLINK=m
+CONFIG_NF_TABLES=m
+CONFIG_NFT_COMPAT=m
+CONFIG_NETFILTER_XTABLES=m
+CONFIG_NETFILTER_XT_MATCH_BPF=m
+CONFIG_NETFILTER_XT_MATCH_LENGTH=m
+CONFIG_NETFILTER_XT_MATCH_STATISTIC=m
+CONFIG_NETFILTER_XT_TARGET_MARK=m
+CONFIG_NF_TABLES_INET=y
+CONFIG_NFT_TPROXY=m
+CONFIG_NFT_SOCKET=m
+CONFIG_IP_ADVANCED_ROUTER=y
+CONFIG_IP_MULTIPLE_TABLES=y
+CONFIG_IP_NF_TARGET_REJECT=m
+CONFIG_IPV6_MULTIPLE_TABLES=y
+CONFIG_NET_ACT_CSUM=m
+CONFIG_NET_ACT_PEDIT=m
+CONFIG_NET_CLS_ACT=y
+CONFIG_NET_CLS_FW=m
+CONFIG_NET_SCH_INGRESS=m
diff --git a/tools/testing/selftests/net/mptcp/diag.sh b/tools/testing/selftests/net/mptcp/diag.sh
new file mode 100755
index 000000000..400cf1ce9
--- /dev/null
+++ b/tools/testing/selftests/net/mptcp/diag.sh
@@ -0,0 +1,241 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+. "$(dirname "${0}")/mptcp_lib.sh"
+
+rndh=$(printf %x $sec)-$(mktemp -u XXXXXX)
+ns="ns1-$rndh"
+ksft_skip=4
+test_cnt=1
+timeout_poll=100
+timeout_test=$((timeout_poll * 2 + 1))
+ret=0
+
+flush_pids()
+{
+	# mptcp_connect in join mode will sleep a bit before completing,
+	# give it some time
+	sleep 1.1
+
+	ip netns pids "${ns}" | xargs --no-run-if-empty kill -SIGUSR1 &>/dev/null
+}
+
+cleanup()
+{
+	ip netns pids "${ns}" | xargs --no-run-if-empty kill -SIGKILL &>/dev/null
+
+	ip netns del $ns
+}
+
+mptcp_lib_check_mptcp
+
+ip -Version > /dev/null 2>&1
+if [ $? -ne 0 ];then
+	echo "SKIP: Could not run test without ip tool"
+	exit $ksft_skip
+fi
+ss -h | grep -q MPTCP
+if [ $? -ne 0 ];then
+	echo "SKIP: ss tool does not support MPTCP"
+	exit $ksft_skip
+fi
+
+__chk_nr()
+{
+	local command="$1"
+	local expected=$2
+	local msg="$3"
+	local skip="${4:-SKIP}"
+	local nr
+
+	nr=$(eval $command)
+
+	printf "%-50s" "$msg"
+	if [ $nr != $expected ]; then
+		if [ $nr = "$skip" ] && ! mptcp_lib_expect_all_features; then
+			echo "[ skip ] Feature probably not supported"
+		else
+			echo "[ fail ] expected $expected found $nr"
+			ret=$test_cnt
+		fi
+	else
+		echo "[  ok  ]"
+	fi
+	test_cnt=$((test_cnt+1))
+}
+
+__chk_msk_nr()
+{
+	local condition=$1
+	shift 1
+
+	__chk_nr "ss -inmHMN $ns | $condition" "$@"
+}
+
+chk_msk_nr()
+{
+	__chk_msk_nr "grep -c token:" "$@"
+}
+
+wait_msk_nr()
+{
+	local condition="grep -c token:"
+	local expected=$1
+	local timeout=20
+	local msg nr
+	local max=0
+	local i=0
+
+	shift 1
+	msg=$*
+
+	while [ $i -lt $timeout ]; do
+		nr=$(ss -inmHMN $ns | $condition)
+		[ $nr == $expected ] && break;
+		[ $nr -gt $max ] && max=$nr
+		i=$((i + 1))
+		sleep 1
+	done
+
+	printf "%-50s" "$msg"
+	if [ $i -ge $timeout ]; then
+		echo "[ fail ] timeout while expecting $expected max $max last $nr"
+		ret=$test_cnt
+	elif [ $nr != $expected ]; then
+		echo "[ fail ] expected $expected found $nr"
+		ret=$test_cnt
+	else
+		echo "[  ok  ]"
+	fi
+	test_cnt=$((test_cnt+1))
+}
+
+chk_msk_fallback_nr()
+{
+	__chk_msk_nr "grep -c fallback" "$@"
+}
+
+chk_msk_remote_key_nr()
+{
+	__chk_msk_nr "grep -c remote_key" "$@"
+}
+
+__chk_listen()
+{
+	local filter="$1"
+	local expected=$2
+	local msg="$3"
+
+	__chk_nr "ss -N $ns -Ml '$filter' | grep -c LISTEN" "$expected" "$msg" 0
+}
+
+chk_msk_listen()
+{
+	lport=$1
+
+	# destination port search should always return empty list
+	__chk_listen "dport $lport" 0 "listen match for dport $lport"
+
+	# should return 'our' mptcp listen socket
+	__chk_listen "sport $lport" 1 "listen match for sport $lport"
+
+	__chk_listen "src inet:0.0.0.0:$lport" 1 "listen match for saddr and sport"
+
+	__chk_listen "" 1 "all listen sockets"
+
+	nr=$(ss -Ml $filter | wc -l)
+}
+
+# $1: ns, $2: port
+wait_local_port_listen()
+{
+	local listener_ns="${1}"
+	local port="${2}"
+
+	local port_hex i
+
+	port_hex="$(printf "%04X" "${port}")"
+	for i in $(seq 10); do
+		ip netns exec "${listener_ns}" cat /proc/net/tcp | \
+			awk "BEGIN {rc=1} {if (\$2 ~ /:${port_hex}\$/ && \$4 ~ /0A/) {rc=0; exit}} END {exit rc}" &&
+			break
+		sleep 0.1
+	done
+}
+
+wait_connected()
+{
+	local listener_ns="${1}"
+	local port="${2}"
+
+	local port_hex i
+
+	port_hex="$(printf "%04X" "${port}")"
+	for i in $(seq 10); do
+		ip netns exec ${listener_ns} grep -q " 0100007F:${port_hex} " /proc/net/tcp && break
+		sleep 0.1
+	done
+}
+
+trap cleanup EXIT
+ip netns add $ns
+ip -n $ns link set dev lo up
+
+echo "a" | \
+	timeout ${timeout_test} \
+		ip netns exec $ns \
+			./mptcp_connect -p 10000 -l -t ${timeout_poll} -w 20 \
+				0.0.0.0 >/dev/null &
+wait_local_port_listen $ns 10000
+chk_msk_nr 0 "no msk on netns creation"
+chk_msk_listen 10000
+
+echo "b" | \
+	timeout ${timeout_test} \
+		ip netns exec $ns \
+			./mptcp_connect -p 10000 -r 0 -t ${timeout_poll} -w 20 \
+				127.0.0.1 >/dev/null &
+wait_connected $ns 10000
+chk_msk_nr 2 "after MPC handshake "
+chk_msk_remote_key_nr 2 "....chk remote_key"
+chk_msk_fallback_nr 0 "....chk no fallback"
+flush_pids
+
+
+echo "a" | \
+	timeout ${timeout_test} \
+		ip netns exec $ns \
+			./mptcp_connect -p 10001 -l -s TCP -t ${timeout_poll} -w 20 \
+				0.0.0.0 >/dev/null &
+wait_local_port_listen $ns 10001
+echo "b" | \
+	timeout ${timeout_test} \
+		ip netns exec $ns \
+			./mptcp_connect -p 10001 -r 0 -t ${timeout_poll} -w 20 \
+				127.0.0.1 >/dev/null &
+wait_connected $ns 10001
+chk_msk_fallback_nr 1 "check fallback"
+flush_pids
+
+NR_CLIENTS=100
+for I in `seq 1 $NR_CLIENTS`; do
+	echo "a" | \
+		timeout ${timeout_test} \
+			ip netns exec $ns \
+				./mptcp_connect -p $((I+10001)) -l -w 20 \
+					-t ${timeout_poll} 0.0.0.0 >/dev/null &
+done
+wait_local_port_listen $ns $((NR_CLIENTS + 10001))
+
+for I in `seq 1 $NR_CLIENTS`; do
+	echo "b" | \
+		timeout ${timeout_test} \
+			ip netns exec $ns \
+				./mptcp_connect -p $((I+10001)) -w 20 \
+					-t ${timeout_poll} 127.0.0.1 >/dev/null &
+done
+
+wait_msk_nr $((NR_CLIENTS*2)) "many msk socket present"
+flush_pids
+
+exit $ret
diff --git a/tools/testing/selftests/net/mptcp/mptcp_connect.c b/tools/testing/selftests/net/mptcp/mptcp_connect.c
new file mode 100644
index 000000000..e6b514cb7
--- /dev/null
+++ b/tools/testing/selftests/net/mptcp/mptcp_connect.c
@@ -0,0 +1,1415 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#define _GNU_SOURCE
+
+#include <errno.h>
+#include <limits.h>
+#include <fcntl.h>
+#include <string.h>
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <strings.h>
+#include <signal.h>
+#include <unistd.h>
+#include <time.h>
+
+#include <sys/ioctl.h>
+#include <sys/poll.h>
+#include <sys/random.h>
+#include <sys/sendfile.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <sys/mman.h>
+
+#include <netdb.h>
+#include <netinet/in.h>
+
+#include <linux/tcp.h>
+#include <linux/time_types.h>
+#include <linux/sockios.h>
+
+extern int optind;
+
+#ifndef IPPROTO_MPTCP
+#define IPPROTO_MPTCP 262
+#endif
+#ifndef TCP_ULP
+#define TCP_ULP 31
+#endif
+
+static int  poll_timeout = 10 * 1000;
+static bool listen_mode;
+static bool quit;
+
+enum cfg_mode {
+	CFG_MODE_POLL,
+	CFG_MODE_MMAP,
+	CFG_MODE_SENDFILE,
+};
+
+enum cfg_peek {
+	CFG_NONE_PEEK,
+	CFG_WITH_PEEK,
+	CFG_AFTER_PEEK,
+};
+
+static enum cfg_mode cfg_mode = CFG_MODE_POLL;
+static enum cfg_peek cfg_peek = CFG_NONE_PEEK;
+static const char *cfg_host;
+static const char *cfg_port	= "12000";
+static int cfg_sock_proto	= IPPROTO_MPTCP;
+static int pf = AF_INET;
+static int cfg_sndbuf;
+static int cfg_rcvbuf;
+static bool cfg_join;
+static bool cfg_remove;
+static unsigned int cfg_time;
+static unsigned int cfg_do_w;
+static int cfg_wait;
+static uint32_t cfg_mark;
+static char *cfg_input;
+static int cfg_repeat = 1;
+static int cfg_truncate;
+static int cfg_rcv_trunc;
+
+struct cfg_cmsg_types {
+	unsigned int cmsg_enabled:1;
+	unsigned int timestampns:1;
+	unsigned int tcp_inq:1;
+};
+
+struct cfg_sockopt_types {
+	unsigned int transparent:1;
+};
+
+struct tcp_inq_state {
+	unsigned int last;
+	bool expect_eof;
+};
+
+static struct tcp_inq_state tcp_inq;
+
+static struct cfg_cmsg_types cfg_cmsg_types;
+static struct cfg_sockopt_types cfg_sockopt_types;
+
+static void die_usage(void)
+{
+	fprintf(stderr, "Usage: mptcp_connect [-6] [-c cmsg] [-f offset] [-i file] [-I num] [-j] [-l] "
+		"[-m mode] [-M mark] [-o option] [-p port] [-P mode] [-r num] [-R num] "
+		"[-s MPTCP|TCP] [-S num] [-t num] [-T num] [-w sec] connect_address\n");
+	fprintf(stderr, "\t-6 use ipv6\n");
+	fprintf(stderr, "\t-c cmsg -- test cmsg type <cmsg>\n");
+	fprintf(stderr, "\t-f offset -- stop the I/O after receiving and sending the specified amount "
+		"of bytes. If there are unread bytes in the receive queue, that will cause a MPTCP "
+		"fastclose at close/shutdown. If offset is negative, expect the peer to close before "
+		"all the local data as been sent, thus toleration errors on write and EPIPE signals\n");
+	fprintf(stderr, "\t-i file -- read the data to send from the given file instead of stdin");
+	fprintf(stderr, "\t-I num -- repeat the transfer 'num' times. In listen mode accepts num "
+		"incoming connections, in client mode, disconnect and reconnect to the server\n");
+	fprintf(stderr, "\t-j     -- add additional sleep at connection start and tear down "
+		"-- for MPJ tests\n");
+	fprintf(stderr, "\t-l     -- listens mode, accepts incoming connection\n");
+	fprintf(stderr, "\t-m [poll|mmap|sendfile] -- use poll(default)/mmap+write/sendfile\n");
+	fprintf(stderr, "\t-M mark -- set socket packet mark\n");
+	fprintf(stderr, "\t-o option -- test sockopt <option>\n");
+	fprintf(stderr, "\t-p num -- use port num\n");
+	fprintf(stderr,
+		"\t-P [saveWithPeek|saveAfterPeek] -- save data with/after MSG_PEEK form tcp socket\n");
+	fprintf(stderr, "\t-r num -- enable slow mode, limiting each write to num bytes "
+		"-- for remove addr tests\n");
+	fprintf(stderr, "\t-R num -- set SO_RCVBUF to num\n");
+	fprintf(stderr, "\t-s [MPTCP|TCP] -- use mptcp(default) or tcp sockets\n");
+	fprintf(stderr, "\t-S num -- set SO_SNDBUF to num\n");
+	fprintf(stderr, "\t-t num -- set poll timeout to num\n");
+	fprintf(stderr, "\t-T num -- set expected runtime to num ms\n");
+	fprintf(stderr, "\t-w num -- wait num sec before closing the socket\n");
+	exit(1);
+}
+
+static void xerror(const char *fmt, ...)
+{
+	va_list ap;
+
+	va_start(ap, fmt);
+	vfprintf(stderr, fmt, ap);
+	va_end(ap);
+	exit(1);
+}
+
+static void handle_signal(int nr)
+{
+	quit = true;
+}
+
+static const char *getxinfo_strerr(int err)
+{
+	if (err == EAI_SYSTEM)
+		return strerror(errno);
+
+	return gai_strerror(err);
+}
+
+static void xgetnameinfo(const struct sockaddr *addr, socklen_t addrlen,
+			 char *host, socklen_t hostlen,
+			 char *serv, socklen_t servlen)
+{
+	int flags = NI_NUMERICHOST | NI_NUMERICSERV;
+	int err = getnameinfo(addr, addrlen, host, hostlen, serv, servlen,
+			      flags);
+
+	if (err) {
+		const char *errstr = getxinfo_strerr(err);
+
+		fprintf(stderr, "Fatal: getnameinfo: %s\n", errstr);
+		exit(1);
+	}
+}
+
+static void xgetaddrinfo(const char *node, const char *service,
+			 const struct addrinfo *hints,
+			 struct addrinfo **res)
+{
+	int err = getaddrinfo(node, service, hints, res);
+
+	if (err) {
+		const char *errstr = getxinfo_strerr(err);
+
+		fprintf(stderr, "Fatal: getaddrinfo(%s:%s): %s\n",
+			node ? node : "", service ? service : "", errstr);
+		exit(1);
+	}
+}
+
+static void set_rcvbuf(int fd, unsigned int size)
+{
+	int err;
+
+	err = setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &size, sizeof(size));
+	if (err) {
+		perror("set SO_RCVBUF");
+		exit(1);
+	}
+}
+
+static void set_sndbuf(int fd, unsigned int size)
+{
+	int err;
+
+	err = setsockopt(fd, SOL_SOCKET, SO_SNDBUF, &size, sizeof(size));
+	if (err) {
+		perror("set SO_SNDBUF");
+		exit(1);
+	}
+}
+
+static void set_mark(int fd, uint32_t mark)
+{
+	int err;
+
+	err = setsockopt(fd, SOL_SOCKET, SO_MARK, &mark, sizeof(mark));
+	if (err) {
+		perror("set SO_MARK");
+		exit(1);
+	}
+}
+
+static void set_transparent(int fd, int pf)
+{
+	int one = 1;
+
+	switch (pf) {
+	case AF_INET:
+		if (-1 == setsockopt(fd, SOL_IP, IP_TRANSPARENT, &one, sizeof(one)))
+			perror("IP_TRANSPARENT");
+		break;
+	case AF_INET6:
+		if (-1 == setsockopt(fd, IPPROTO_IPV6, IPV6_TRANSPARENT, &one, sizeof(one)))
+			perror("IPV6_TRANSPARENT");
+		break;
+	}
+}
+
+static int do_ulp_so(int sock, const char *name)
+{
+	return setsockopt(sock, IPPROTO_TCP, TCP_ULP, name, strlen(name));
+}
+
+#define X(m)	xerror("%s:%u: %s: failed for proto %d at line %u", __FILE__, __LINE__, (m), proto, line)
+static void sock_test_tcpulp(int sock, int proto, unsigned int line)
+{
+	socklen_t buflen = 8;
+	char buf[8] = "";
+	int ret = getsockopt(sock, IPPROTO_TCP, TCP_ULP, buf, &buflen);
+
+	if (ret != 0)
+		X("getsockopt");
+
+	if (buflen > 0) {
+		if (strcmp(buf, "mptcp") != 0)
+			xerror("unexpected ULP '%s' for proto %d at line %u", buf, proto, line);
+		ret = do_ulp_so(sock, "tls");
+		if (ret == 0)
+			X("setsockopt");
+	} else if (proto == IPPROTO_MPTCP) {
+		ret = do_ulp_so(sock, "tls");
+		if (ret != -1)
+			X("setsockopt");
+	}
+
+	ret = do_ulp_so(sock, "mptcp");
+	if (ret != -1)
+		X("setsockopt");
+
+#undef X
+}
+
+#define SOCK_TEST_TCPULP(s, p) sock_test_tcpulp((s), (p), __LINE__)
+
+static int sock_listen_mptcp(const char * const listenaddr,
+			     const char * const port)
+{
+	int sock = -1;
+	struct addrinfo hints = {
+		.ai_protocol = IPPROTO_TCP,
+		.ai_socktype = SOCK_STREAM,
+		.ai_flags = AI_PASSIVE | AI_NUMERICHOST
+	};
+
+	hints.ai_family = pf;
+
+	struct addrinfo *a, *addr;
+	int one = 1;
+
+	xgetaddrinfo(listenaddr, port, &hints, &addr);
+	hints.ai_family = pf;
+
+	for (a = addr; a; a = a->ai_next) {
+		sock = socket(a->ai_family, a->ai_socktype, cfg_sock_proto);
+		if (sock < 0)
+			continue;
+
+		SOCK_TEST_TCPULP(sock, cfg_sock_proto);
+
+		if (-1 == setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &one,
+				     sizeof(one)))
+			perror("setsockopt");
+
+		if (cfg_sockopt_types.transparent)
+			set_transparent(sock, pf);
+
+		if (bind(sock, a->ai_addr, a->ai_addrlen) == 0)
+			break; /* success */
+
+		perror("bind");
+		close(sock);
+		sock = -1;
+	}
+
+	freeaddrinfo(addr);
+
+	if (sock < 0) {
+		fprintf(stderr, "Could not create listen socket\n");
+		return sock;
+	}
+
+	SOCK_TEST_TCPULP(sock, cfg_sock_proto);
+
+	if (listen(sock, 20)) {
+		perror("listen");
+		close(sock);
+		return -1;
+	}
+
+	SOCK_TEST_TCPULP(sock, cfg_sock_proto);
+
+	return sock;
+}
+
+static int sock_connect_mptcp(const char * const remoteaddr,
+			      const char * const port, int proto,
+			      struct addrinfo **peer)
+{
+	struct addrinfo hints = {
+		.ai_protocol = IPPROTO_TCP,
+		.ai_socktype = SOCK_STREAM,
+	};
+	struct addrinfo *a, *addr;
+	int sock = -1;
+
+	hints.ai_family = pf;
+
+	xgetaddrinfo(remoteaddr, port, &hints, &addr);
+	for (a = addr; a; a = a->ai_next) {
+		sock = socket(a->ai_family, a->ai_socktype, proto);
+		if (sock < 0) {
+			perror("socket");
+			continue;
+		}
+
+		SOCK_TEST_TCPULP(sock, proto);
+
+		if (cfg_mark)
+			set_mark(sock, cfg_mark);
+
+		if (connect(sock, a->ai_addr, a->ai_addrlen) == 0) {
+			*peer = a;
+			break; /* success */
+		}
+
+		perror("connect()");
+		close(sock);
+		sock = -1;
+	}
+
+	freeaddrinfo(addr);
+	if (sock != -1)
+		SOCK_TEST_TCPULP(sock, proto);
+	return sock;
+}
+
+static size_t do_rnd_write(const int fd, char *buf, const size_t len)
+{
+	static bool first = true;
+	unsigned int do_w;
+	ssize_t bw;
+
+	do_w = rand() & 0xffff;
+	if (do_w == 0 || do_w > len)
+		do_w = len;
+
+	if (cfg_join && first && do_w > 100)
+		do_w = 100;
+
+	if (cfg_remove && do_w > cfg_do_w)
+		do_w = cfg_do_w;
+
+	bw = write(fd, buf, do_w);
+	if (bw < 0)
+		return bw;
+
+	/* let the join handshake complete, before going on */
+	if (cfg_join && first) {
+		usleep(200000);
+		first = false;
+	}
+
+	if (cfg_remove)
+		usleep(200000);
+
+	return bw;
+}
+
+static size_t do_write(const int fd, char *buf, const size_t len)
+{
+	size_t offset = 0;
+
+	while (offset < len) {
+		size_t written;
+		ssize_t bw;
+
+		bw = write(fd, buf + offset, len - offset);
+		if (bw < 0) {
+			perror("write");
+			return 0;
+		}
+
+		written = (size_t)bw;
+		offset += written;
+	}
+
+	return offset;
+}
+
+static void process_cmsg(struct msghdr *msgh)
+{
+	struct __kernel_timespec ts;
+	bool inq_found = false;
+	bool ts_found = false;
+	unsigned int inq = 0;
+	struct cmsghdr *cmsg;
+
+	for (cmsg = CMSG_FIRSTHDR(msgh); cmsg ; cmsg = CMSG_NXTHDR(msgh, cmsg)) {
+		if (cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SO_TIMESTAMPNS_NEW) {
+			memcpy(&ts, CMSG_DATA(cmsg), sizeof(ts));
+			ts_found = true;
+			continue;
+		}
+		if (cmsg->cmsg_level == IPPROTO_TCP && cmsg->cmsg_type == TCP_CM_INQ) {
+			memcpy(&inq, CMSG_DATA(cmsg), sizeof(inq));
+			inq_found = true;
+			continue;
+		}
+
+	}
+
+	if (cfg_cmsg_types.timestampns) {
+		if (!ts_found)
+			xerror("TIMESTAMPNS not present\n");
+	}
+
+	if (cfg_cmsg_types.tcp_inq) {
+		if (!inq_found)
+			xerror("TCP_INQ not present\n");
+
+		if (inq > 1024)
+			xerror("tcp_inq %u is larger than one kbyte\n", inq);
+		tcp_inq.last = inq;
+	}
+}
+
+static ssize_t do_recvmsg_cmsg(const int fd, char *buf, const size_t len)
+{
+	char msg_buf[8192];
+	struct iovec iov = {
+		.iov_base = buf,
+		.iov_len = len,
+	};
+	struct msghdr msg = {
+		.msg_iov = &iov,
+		.msg_iovlen = 1,
+		.msg_control = msg_buf,
+		.msg_controllen = sizeof(msg_buf),
+	};
+	int flags = 0;
+	unsigned int last_hint = tcp_inq.last;
+	int ret = recvmsg(fd, &msg, flags);
+
+	if (ret <= 0) {
+		if (ret == 0 && tcp_inq.expect_eof)
+			return ret;
+
+		if (ret == 0 && cfg_cmsg_types.tcp_inq)
+			if (last_hint != 1 && last_hint != 0)
+				xerror("EOF but last tcp_inq hint was %u\n", last_hint);
+
+		return ret;
+	}
+
+	if (tcp_inq.expect_eof)
+		xerror("expected EOF, last_hint %u, now %u\n",
+		       last_hint, tcp_inq.last);
+
+	if (msg.msg_controllen && !cfg_cmsg_types.cmsg_enabled)
+		xerror("got %lu bytes of cmsg data, expected 0\n",
+		       (unsigned long)msg.msg_controllen);
+
+	if (msg.msg_controllen == 0 && cfg_cmsg_types.cmsg_enabled)
+		xerror("%s\n", "got no cmsg data");
+
+	if (msg.msg_controllen)
+		process_cmsg(&msg);
+
+	if (cfg_cmsg_types.tcp_inq) {
+		if ((size_t)ret < len && last_hint > (unsigned int)ret) {
+			if (ret + 1 != (int)last_hint) {
+				int next = read(fd, msg_buf, sizeof(msg_buf));
+
+				xerror("read %u of %u, last_hint was %u tcp_inq hint now %u next_read returned %d/%m\n",
+				       ret, (unsigned int)len, last_hint, tcp_inq.last, next);
+			} else {
+				tcp_inq.expect_eof = true;
+			}
+		}
+	}
+
+	return ret;
+}
+
+static ssize_t do_rnd_read(const int fd, char *buf, const size_t len)
+{
+	int ret = 0;
+	char tmp[16384];
+	size_t cap = rand();
+
+	cap &= 0xffff;
+
+	if (cap == 0)
+		cap = 1;
+	else if (cap > len)
+		cap = len;
+
+	if (cfg_peek == CFG_WITH_PEEK) {
+		ret = recv(fd, buf, cap, MSG_PEEK);
+		ret = (ret < 0) ? ret : read(fd, tmp, ret);
+	} else if (cfg_peek == CFG_AFTER_PEEK) {
+		ret = recv(fd, buf, cap, MSG_PEEK);
+		ret = (ret < 0) ? ret : read(fd, buf, cap);
+	} else if (cfg_cmsg_types.cmsg_enabled) {
+		ret = do_recvmsg_cmsg(fd, buf, cap);
+	} else {
+		ret = read(fd, buf, cap);
+	}
+
+	return ret;
+}
+
+static void set_nonblock(int fd, bool nonblock)
+{
+	int flags = fcntl(fd, F_GETFL);
+
+	if (flags == -1)
+		return;
+
+	if (nonblock)
+		fcntl(fd, F_SETFL, flags | O_NONBLOCK);
+	else
+		fcntl(fd, F_SETFL, flags & ~O_NONBLOCK);
+}
+
+static void shut_wr(int fd)
+{
+	/* Close our write side, ev. give some time
+	 * for address notification and/or checking
+	 * the current status
+	 */
+	if (cfg_wait)
+		usleep(cfg_wait);
+
+	shutdown(fd, SHUT_WR);
+}
+
+static int copyfd_io_poll(int infd, int peerfd, int outfd, bool *in_closed_after_out)
+{
+	struct pollfd fds = {
+		.fd = peerfd,
+		.events = POLLIN | POLLOUT,
+	};
+	unsigned int woff = 0, wlen = 0, total_wlen = 0, total_rlen = 0;
+	char wbuf[8192];
+
+	set_nonblock(peerfd, true);
+
+	for (;;) {
+		char rbuf[8192];
+		ssize_t len;
+
+		if (fds.events == 0)
+			break;
+
+		switch (poll(&fds, 1, poll_timeout)) {
+		case -1:
+			if (errno == EINTR)
+				continue;
+			perror("poll");
+			return 1;
+		case 0:
+			fprintf(stderr, "%s: poll timed out (events: "
+				"POLLIN %u, POLLOUT %u)\n", __func__,
+				fds.events & POLLIN, fds.events & POLLOUT);
+			return 2;
+		}
+
+		if (fds.revents & POLLIN) {
+			ssize_t rb = sizeof(rbuf);
+
+			/* limit the total amount of read data to the trunc value*/
+			if (cfg_truncate > 0) {
+				if (rb + total_rlen > cfg_truncate)
+					rb = cfg_truncate - total_rlen;
+				len = read(peerfd, rbuf, rb);
+			} else {
+				len = do_rnd_read(peerfd, rbuf, sizeof(rbuf));
+			}
+			if (len == 0) {
+				/* no more data to receive:
+				 * peer has closed its write side
+				 */
+				fds.events &= ~POLLIN;
+
+				if ((fds.events & POLLOUT) == 0) {
+					*in_closed_after_out = true;
+					/* and nothing more to send */
+					break;
+				}
+
+			/* Else, still have data to transmit */
+			} else if (len < 0) {
+				if (cfg_rcv_trunc)
+					return 0;
+				perror("read");
+				return 3;
+			}
+
+			total_rlen += len;
+			do_write(outfd, rbuf, len);
+		}
+
+		if (fds.revents & POLLOUT) {
+			if (wlen == 0) {
+				woff = 0;
+				wlen = read(infd, wbuf, sizeof(wbuf));
+			}
+
+			if (wlen > 0) {
+				ssize_t bw;
+
+				/* limit the total amount of written data to the trunc value */
+				if (cfg_truncate > 0 && wlen + total_wlen > cfg_truncate)
+					wlen = cfg_truncate - total_wlen;
+
+				bw = do_rnd_write(peerfd, wbuf + woff, wlen);
+				if (bw < 0) {
+					if (cfg_rcv_trunc)
+						return 0;
+					perror("write");
+					return 111;
+				}
+
+				woff += bw;
+				wlen -= bw;
+				total_wlen += bw;
+			} else if (wlen == 0) {
+				/* We have no more data to send. */
+				fds.events &= ~POLLOUT;
+
+				if ((fds.events & POLLIN) == 0)
+					/* ... and peer also closed already */
+					break;
+
+				shut_wr(peerfd);
+			} else {
+				if (errno == EINTR)
+					continue;
+				perror("read");
+				return 4;
+			}
+		}
+
+		if (fds.revents & (POLLERR | POLLNVAL)) {
+			if (cfg_rcv_trunc)
+				return 0;
+			fprintf(stderr, "Unexpected revents: "
+				"POLLERR/POLLNVAL(%x)\n", fds.revents);
+			return 5;
+		}
+
+		if (cfg_truncate > 0 && total_wlen >= cfg_truncate &&
+		    total_rlen >= cfg_truncate)
+			break;
+	}
+
+	/* leave some time for late join/announce */
+	if (cfg_remove)
+		usleep(cfg_wait);
+
+	return 0;
+}
+
+static int do_recvfile(int infd, int outfd)
+{
+	ssize_t r;
+
+	do {
+		char buf[16384];
+
+		r = do_rnd_read(infd, buf, sizeof(buf));
+		if (r > 0) {
+			if (write(outfd, buf, r) != r)
+				break;
+		} else if (r < 0) {
+			perror("read");
+		}
+	} while (r > 0);
+
+	return (int)r;
+}
+
+static int do_mmap(int infd, int outfd, unsigned int size)
+{
+	char *inbuf = mmap(NULL, size, PROT_READ, MAP_SHARED, infd, 0);
+	ssize_t ret = 0, off = 0;
+	size_t rem;
+
+	if (inbuf == MAP_FAILED) {
+		perror("mmap");
+		return 1;
+	}
+
+	rem = size;
+
+	while (rem > 0) {
+		ret = write(outfd, inbuf + off, rem);
+
+		if (ret < 0) {
+			perror("write");
+			break;
+		}
+
+		off += ret;
+		rem -= ret;
+	}
+
+	munmap(inbuf, size);
+	return rem;
+}
+
+static int get_infd_size(int fd)
+{
+	struct stat sb;
+	ssize_t count;
+	int err;
+
+	err = fstat(fd, &sb);
+	if (err < 0) {
+		perror("fstat");
+		return -1;
+	}
+
+	if ((sb.st_mode & S_IFMT) != S_IFREG) {
+		fprintf(stderr, "%s: stdin is not a regular file\n", __func__);
+		return -2;
+	}
+
+	count = sb.st_size;
+	if (count > INT_MAX) {
+		fprintf(stderr, "File too large: %zu\n", count);
+		return -3;
+	}
+
+	return (int)count;
+}
+
+static int do_sendfile(int infd, int outfd, unsigned int count)
+{
+	while (count > 0) {
+		ssize_t r;
+
+		r = sendfile(outfd, infd, NULL, count);
+		if (r < 0) {
+			perror("sendfile");
+			return 3;
+		}
+
+		count -= r;
+	}
+
+	return 0;
+}
+
+static int copyfd_io_mmap(int infd, int peerfd, int outfd,
+			  unsigned int size, bool *in_closed_after_out)
+{
+	int err;
+
+	if (listen_mode) {
+		err = do_recvfile(peerfd, outfd);
+		if (err)
+			return err;
+
+		err = do_mmap(infd, peerfd, size);
+	} else {
+		err = do_mmap(infd, peerfd, size);
+		if (err)
+			return err;
+
+		shut_wr(peerfd);
+
+		err = do_recvfile(peerfd, outfd);
+		*in_closed_after_out = true;
+	}
+
+	return err;
+}
+
+static int copyfd_io_sendfile(int infd, int peerfd, int outfd,
+			      unsigned int size, bool *in_closed_after_out)
+{
+	int err;
+
+	if (listen_mode) {
+		err = do_recvfile(peerfd, outfd);
+		if (err)
+			return err;
+
+		err = do_sendfile(infd, peerfd, size);
+	} else {
+		err = do_sendfile(infd, peerfd, size);
+		if (err)
+			return err;
+
+		shut_wr(peerfd);
+
+		err = do_recvfile(peerfd, outfd);
+		*in_closed_after_out = true;
+	}
+
+	return err;
+}
+
+static int copyfd_io(int infd, int peerfd, int outfd, bool close_peerfd)
+{
+	bool in_closed_after_out = false;
+	struct timespec start, end;
+	int file_size;
+	int ret;
+
+	if (cfg_time && (clock_gettime(CLOCK_MONOTONIC, &start) < 0))
+		xerror("can not fetch start time %d", errno);
+
+	switch (cfg_mode) {
+	case CFG_MODE_POLL:
+		ret = copyfd_io_poll(infd, peerfd, outfd, &in_closed_after_out);
+		break;
+
+	case CFG_MODE_MMAP:
+		file_size = get_infd_size(infd);
+		if (file_size < 0)
+			return file_size;
+		ret = copyfd_io_mmap(infd, peerfd, outfd, file_size, &in_closed_after_out);
+		break;
+
+	case CFG_MODE_SENDFILE:
+		file_size = get_infd_size(infd);
+		if (file_size < 0)
+			return file_size;
+		ret = copyfd_io_sendfile(infd, peerfd, outfd, file_size, &in_closed_after_out);
+		break;
+
+	default:
+		fprintf(stderr, "Invalid mode %d\n", cfg_mode);
+
+		die_usage();
+		return 1;
+	}
+
+	if (ret)
+		return ret;
+
+	if (close_peerfd)
+		close(peerfd);
+
+	if (cfg_time) {
+		unsigned int delta_ms;
+
+		if (clock_gettime(CLOCK_MONOTONIC, &end) < 0)
+			xerror("can not fetch end time %d", errno);
+		delta_ms = (end.tv_sec - start.tv_sec) * 1000 + (end.tv_nsec - start.tv_nsec) / 1000000;
+		if (delta_ms > cfg_time) {
+			xerror("transfer slower than expected! runtime %d ms, expected %d ms",
+			       delta_ms, cfg_time);
+		}
+
+		/* show the runtime only if this end shutdown(wr) before receiving the EOF,
+		 * (that is, if this end got the longer runtime)
+		 */
+		if (in_closed_after_out)
+			fprintf(stderr, "%d", delta_ms);
+	}
+
+	return 0;
+}
+
+static void check_sockaddr(int pf, struct sockaddr_storage *ss,
+			   socklen_t salen)
+{
+	struct sockaddr_in6 *sin6;
+	struct sockaddr_in *sin;
+	socklen_t wanted_size = 0;
+
+	switch (pf) {
+	case AF_INET:
+		wanted_size = sizeof(*sin);
+		sin = (void *)ss;
+		if (!sin->sin_port)
+			fprintf(stderr, "accept: something wrong: ip connection from port 0");
+		break;
+	case AF_INET6:
+		wanted_size = sizeof(*sin6);
+		sin6 = (void *)ss;
+		if (!sin6->sin6_port)
+			fprintf(stderr, "accept: something wrong: ipv6 connection from port 0");
+		break;
+	default:
+		fprintf(stderr, "accept: Unknown pf %d, salen %u\n", pf, salen);
+		return;
+	}
+
+	if (salen != wanted_size)
+		fprintf(stderr, "accept: size mismatch, got %d expected %d\n",
+			(int)salen, wanted_size);
+
+	if (ss->ss_family != pf)
+		fprintf(stderr, "accept: pf mismatch, expect %d, ss_family is %d\n",
+			(int)ss->ss_family, pf);
+}
+
+static void check_getpeername(int fd, struct sockaddr_storage *ss, socklen_t salen)
+{
+	struct sockaddr_storage peerss;
+	socklen_t peersalen = sizeof(peerss);
+
+	if (getpeername(fd, (struct sockaddr *)&peerss, &peersalen) < 0) {
+		perror("getpeername");
+		return;
+	}
+
+	if (peersalen != salen) {
+		fprintf(stderr, "%s: %d vs %d\n", __func__, peersalen, salen);
+		return;
+	}
+
+	if (memcmp(ss, &peerss, peersalen)) {
+		char a[INET6_ADDRSTRLEN];
+		char b[INET6_ADDRSTRLEN];
+		char c[INET6_ADDRSTRLEN];
+		char d[INET6_ADDRSTRLEN];
+
+		xgetnameinfo((struct sockaddr *)ss, salen,
+			     a, sizeof(a), b, sizeof(b));
+
+		xgetnameinfo((struct sockaddr *)&peerss, peersalen,
+			     c, sizeof(c), d, sizeof(d));
+
+		fprintf(stderr, "%s: memcmp failure: accept %s vs peername %s, %s vs %s salen %d vs %d\n",
+			__func__, a, c, b, d, peersalen, salen);
+	}
+}
+
+static void check_getpeername_connect(int fd)
+{
+	struct sockaddr_storage ss;
+	socklen_t salen = sizeof(ss);
+	char a[INET6_ADDRSTRLEN];
+	char b[INET6_ADDRSTRLEN];
+
+	if (getpeername(fd, (struct sockaddr *)&ss, &salen) < 0) {
+		perror("getpeername");
+		return;
+	}
+
+	xgetnameinfo((struct sockaddr *)&ss, salen,
+		     a, sizeof(a), b, sizeof(b));
+
+	if (strcmp(cfg_host, a) || strcmp(cfg_port, b))
+		fprintf(stderr, "%s: %s vs %s, %s vs %s\n", __func__,
+			cfg_host, a, cfg_port, b);
+}
+
+static void maybe_close(int fd)
+{
+	unsigned int r = rand();
+
+	if (!(cfg_join || cfg_remove || cfg_repeat > 1) && (r & 1))
+		close(fd);
+}
+
+int main_loop_s(int listensock)
+{
+	struct sockaddr_storage ss;
+	struct pollfd polls;
+	socklen_t salen;
+	int remotesock;
+	int fd = 0;
+
+again:
+	polls.fd = listensock;
+	polls.events = POLLIN;
+
+	switch (poll(&polls, 1, poll_timeout)) {
+	case -1:
+		perror("poll");
+		return 1;
+	case 0:
+		fprintf(stderr, "%s: timed out\n", __func__);
+		close(listensock);
+		return 2;
+	}
+
+	salen = sizeof(ss);
+	remotesock = accept(listensock, (struct sockaddr *)&ss, &salen);
+	if (remotesock >= 0) {
+		maybe_close(listensock);
+		check_sockaddr(pf, &ss, salen);
+		check_getpeername(remotesock, &ss, salen);
+
+		if (cfg_input) {
+			fd = open(cfg_input, O_RDONLY);
+			if (fd < 0)
+				xerror("can't open %s: %d", cfg_input, errno);
+		}
+
+		SOCK_TEST_TCPULP(remotesock, 0);
+
+		copyfd_io(fd, remotesock, 1, true);
+	} else {
+		perror("accept");
+		return 1;
+	}
+
+	if (--cfg_repeat > 0) {
+		if (cfg_input)
+			close(fd);
+		goto again;
+	}
+
+	return 0;
+}
+
+static void init_rng(void)
+{
+	unsigned int foo;
+
+	if (getrandom(&foo, sizeof(foo), 0) == -1) {
+		perror("getrandom");
+		exit(1);
+	}
+
+	srand(foo);
+}
+
+static void xsetsockopt(int fd, int level, int optname, const void *optval, socklen_t optlen)
+{
+	int err;
+
+	err = setsockopt(fd, level, optname, optval, optlen);
+	if (err) {
+		perror("setsockopt");
+		exit(1);
+	}
+}
+
+static void apply_cmsg_types(int fd, const struct cfg_cmsg_types *cmsg)
+{
+	static const unsigned int on = 1;
+
+	if (cmsg->timestampns)
+		xsetsockopt(fd, SOL_SOCKET, SO_TIMESTAMPNS_NEW, &on, sizeof(on));
+	if (cmsg->tcp_inq)
+		xsetsockopt(fd, IPPROTO_TCP, TCP_INQ, &on, sizeof(on));
+}
+
+static void parse_cmsg_types(const char *type)
+{
+	char *next = strchr(type, ',');
+	unsigned int len = 0;
+
+	cfg_cmsg_types.cmsg_enabled = 1;
+
+	if (next) {
+		parse_cmsg_types(next + 1);
+		len = next - type;
+	} else {
+		len = strlen(type);
+	}
+
+	if (strncmp(type, "TIMESTAMPNS", len) == 0) {
+		cfg_cmsg_types.timestampns = 1;
+		return;
+	}
+
+	if (strncmp(type, "TCPINQ", len) == 0) {
+		cfg_cmsg_types.tcp_inq = 1;
+		return;
+	}
+
+	fprintf(stderr, "Unrecognized cmsg option %s\n", type);
+	exit(1);
+}
+
+static void parse_setsock_options(const char *name)
+{
+	char *next = strchr(name, ',');
+	unsigned int len = 0;
+
+	if (next) {
+		parse_setsock_options(next + 1);
+		len = next - name;
+	} else {
+		len = strlen(name);
+	}
+
+	if (strncmp(name, "TRANSPARENT", len) == 0) {
+		cfg_sockopt_types.transparent = 1;
+		return;
+	}
+
+	fprintf(stderr, "Unrecognized setsockopt option %s\n", name);
+	exit(1);
+}
+
+void xdisconnect(int fd, int addrlen)
+{
+	struct sockaddr_storage empty;
+	int msec_sleep = 10;
+	int queued = 1;
+	int i;
+
+	shutdown(fd, SHUT_WR);
+
+	/* while until the pending data is completely flushed, the later
+	 * disconnect will bypass/ignore/drop any pending data.
+	 */
+	for (i = 0; ; i += msec_sleep) {
+		if (ioctl(fd, SIOCOUTQ, &queued) < 0)
+			xerror("can't query out socket queue: %d", errno);
+
+		if (!queued)
+			break;
+
+		if (i > poll_timeout)
+			xerror("timeout while waiting for spool to complete");
+		usleep(msec_sleep * 1000);
+	}
+
+	memset(&empty, 0, sizeof(empty));
+	empty.ss_family = AF_UNSPEC;
+	if (connect(fd, (struct sockaddr *)&empty, addrlen) < 0)
+		xerror("can't disconnect: %d", errno);
+}
+
+int main_loop(void)
+{
+	int fd, ret, fd_in = 0;
+	struct addrinfo *peer;
+
+	/* listener is ready. */
+	fd = sock_connect_mptcp(cfg_host, cfg_port, cfg_sock_proto, &peer);
+	if (fd < 0)
+		return 2;
+
+again:
+	check_getpeername_connect(fd);
+
+	SOCK_TEST_TCPULP(fd, cfg_sock_proto);
+
+	if (cfg_rcvbuf)
+		set_rcvbuf(fd, cfg_rcvbuf);
+	if (cfg_sndbuf)
+		set_sndbuf(fd, cfg_sndbuf);
+	if (cfg_cmsg_types.cmsg_enabled)
+		apply_cmsg_types(fd, &cfg_cmsg_types);
+
+	if (cfg_input) {
+		fd_in = open(cfg_input, O_RDONLY);
+		if (fd < 0)
+			xerror("can't open %s:%d", cfg_input, errno);
+	}
+
+	/* close the client socket open only if we are not going to reconnect */
+	ret = copyfd_io(fd_in, fd, 1, 0);
+	if (ret)
+		return ret;
+
+	if (cfg_truncate > 0) {
+		xdisconnect(fd, peer->ai_addrlen);
+	} else if (--cfg_repeat > 0) {
+		xdisconnect(fd, peer->ai_addrlen);
+
+		/* the socket could be unblocking at this point, we need the
+		 * connect to be blocking
+		 */
+		set_nonblock(fd, false);
+		if (connect(fd, peer->ai_addr, peer->ai_addrlen))
+			xerror("can't reconnect: %d", errno);
+		if (cfg_input)
+			close(fd_in);
+		goto again;
+	} else {
+		close(fd);
+	}
+
+	return 0;
+}
+
+int parse_proto(const char *proto)
+{
+	if (!strcasecmp(proto, "MPTCP"))
+		return IPPROTO_MPTCP;
+	if (!strcasecmp(proto, "TCP"))
+		return IPPROTO_TCP;
+
+	fprintf(stderr, "Unknown protocol: %s\n.", proto);
+	die_usage();
+
+	/* silence compiler warning */
+	return 0;
+}
+
+int parse_mode(const char *mode)
+{
+	if (!strcasecmp(mode, "poll"))
+		return CFG_MODE_POLL;
+	if (!strcasecmp(mode, "mmap"))
+		return CFG_MODE_MMAP;
+	if (!strcasecmp(mode, "sendfile"))
+		return CFG_MODE_SENDFILE;
+
+	fprintf(stderr, "Unknown test mode: %s\n", mode);
+	fprintf(stderr, "Supported modes are:\n");
+	fprintf(stderr, "\t\t\"poll\" - interleaved read/write using poll()\n");
+	fprintf(stderr, "\t\t\"mmap\" - send entire input file (mmap+write), then read response (-l will read input first)\n");
+	fprintf(stderr, "\t\t\"sendfile\" - send entire input file (sendfile), then read response (-l will read input first)\n");
+
+	die_usage();
+
+	/* silence compiler warning */
+	return 0;
+}
+
+int parse_peek(const char *mode)
+{
+	if (!strcasecmp(mode, "saveWithPeek"))
+		return CFG_WITH_PEEK;
+	if (!strcasecmp(mode, "saveAfterPeek"))
+		return CFG_AFTER_PEEK;
+
+	fprintf(stderr, "Unknown: %s\n", mode);
+	fprintf(stderr, "Supported MSG_PEEK mode are:\n");
+	fprintf(stderr,
+		"\t\t\"saveWithPeek\" - recv data with flags 'MSG_PEEK' and save the peek data into file\n");
+	fprintf(stderr,
+		"\t\t\"saveAfterPeek\" - read and save data into file after recv with flags 'MSG_PEEK'\n");
+
+	die_usage();
+
+	/* silence compiler warning */
+	return 0;
+}
+
+static int parse_int(const char *size)
+{
+	unsigned long s;
+
+	errno = 0;
+
+	s = strtoul(size, NULL, 0);
+
+	if (errno) {
+		fprintf(stderr, "Invalid sndbuf size %s (%s)\n",
+			size, strerror(errno));
+		die_usage();
+	}
+
+	if (s > INT_MAX) {
+		fprintf(stderr, "Invalid sndbuf size %s (%s)\n",
+			size, strerror(ERANGE));
+		die_usage();
+	}
+
+	return (int)s;
+}
+
+static void parse_opts(int argc, char **argv)
+{
+	int c;
+
+	while ((c = getopt(argc, argv, "6c:f:hi:I:jlm:M:o:p:P:r:R:s:S:t:T:w:")) != -1) {
+		switch (c) {
+		case 'f':
+			cfg_truncate = atoi(optarg);
+
+			/* when receiving a fastclose, ignore PIPE signals and
+			 * all the I/O errors later in the code
+			 */
+			if (cfg_truncate < 0) {
+				cfg_rcv_trunc = true;
+				signal(SIGPIPE, handle_signal);
+			}
+			break;
+		case 'j':
+			cfg_join = true;
+			cfg_mode = CFG_MODE_POLL;
+			break;
+		case 'r':
+			cfg_remove = true;
+			cfg_mode = CFG_MODE_POLL;
+			cfg_wait = 400000;
+			cfg_do_w = atoi(optarg);
+			if (cfg_do_w <= 0)
+				cfg_do_w = 50;
+			break;
+		case 'i':
+			cfg_input = optarg;
+			break;
+		case 'I':
+			cfg_repeat = atoi(optarg);
+			break;
+		case 'l':
+			listen_mode = true;
+			break;
+		case 'p':
+			cfg_port = optarg;
+			break;
+		case 's':
+			cfg_sock_proto = parse_proto(optarg);
+			break;
+		case 'h':
+			die_usage();
+			break;
+		case '6':
+			pf = AF_INET6;
+			break;
+		case 't':
+			poll_timeout = atoi(optarg) * 1000;
+			if (poll_timeout <= 0)
+				poll_timeout = -1;
+			break;
+		case 'T':
+			cfg_time = atoi(optarg);
+			break;
+		case 'm':
+			cfg_mode = parse_mode(optarg);
+			break;
+		case 'S':
+			cfg_sndbuf = parse_int(optarg);
+			break;
+		case 'R':
+			cfg_rcvbuf = parse_int(optarg);
+			break;
+		case 'w':
+			cfg_wait = atoi(optarg)*1000000;
+			break;
+		case 'M':
+			cfg_mark = strtol(optarg, NULL, 0);
+			break;
+		case 'P':
+			cfg_peek = parse_peek(optarg);
+			break;
+		case 'c':
+			parse_cmsg_types(optarg);
+			break;
+		case 'o':
+			parse_setsock_options(optarg);
+			break;
+		}
+	}
+
+	if (optind + 1 != argc)
+		die_usage();
+	cfg_host = argv[optind];
+
+	if (strchr(cfg_host, ':'))
+		pf = AF_INET6;
+}
+
+int main(int argc, char *argv[])
+{
+	init_rng();
+
+	signal(SIGUSR1, handle_signal);
+	parse_opts(argc, argv);
+
+	if (listen_mode) {
+		int fd = sock_listen_mptcp(cfg_host, cfg_port);
+
+		if (fd < 0)
+			return 1;
+
+		if (cfg_rcvbuf)
+			set_rcvbuf(fd, cfg_rcvbuf);
+		if (cfg_sndbuf)
+			set_sndbuf(fd, cfg_sndbuf);
+		if (cfg_mark)
+			set_mark(fd, cfg_mark);
+		if (cfg_cmsg_types.cmsg_enabled)
+			apply_cmsg_types(fd, &cfg_cmsg_types);
+
+		return main_loop_s(fd);
+	}
+
+	return main_loop();
+}
diff --git a/tools/testing/selftests/net/mptcp/mptcp_connect.sh b/tools/testing/selftests/net/mptcp/mptcp_connect.sh
new file mode 100755
index 000000000..18c9b00ca
--- /dev/null
+++ b/tools/testing/selftests/net/mptcp/mptcp_connect.sh
@@ -0,0 +1,934 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+. "$(dirname "${0}")/mptcp_lib.sh"
+
+time_start=$(date +%s)
+
+optstring="S:R:d:e:l:r:h4cm:f:tC"
+ret=0
+sin=""
+sout=""
+cin_disconnect=""
+cin=""
+cout=""
+ksft_skip=4
+capture=false
+timeout_poll=30
+timeout_test=$((timeout_poll * 2 + 1))
+ipv6=true
+ethtool_random_on=true
+tc_delay="$((RANDOM%50))"
+tc_loss=$((RANDOM%101))
+testmode=""
+sndbuf=0
+rcvbuf=0
+options_log=true
+do_tcp=0
+checksum=false
+filesize=0
+connect_per_transfer=1
+
+if [ $tc_loss -eq 100 ];then
+	tc_loss=1%
+elif [ $tc_loss -ge 10 ]; then
+	tc_loss=0.$tc_loss%
+elif [ $tc_loss -ge 1 ]; then
+	tc_loss=0.0$tc_loss%
+else
+	tc_loss=""
+fi
+
+usage() {
+	echo "Usage: $0 [ -a ]"
+	echo -e "\t-d: tc/netem delay in milliseconds, e.g. \"-d 10\" (default random)"
+	echo -e "\t-l: tc/netem loss percentage, e.g. \"-l 0.02\" (default random)"
+	echo -e "\t-r: tc/netem reorder mode, e.g. \"-r 25% 50% gap 5\", use "-r 0" to disable reordering (default random)"
+	echo -e "\t-e: ethtool features to disable, e.g.: \"-e tso -e gso\" (default: randomly disable any of tso/gso/gro)"
+	echo -e "\t-4: IPv4 only: disable IPv6 tests (default: test both IPv4 and IPv6)"
+	echo -e "\t-c: capture packets for each test using tcpdump (default: no capture)"
+	echo -e "\t-f: size of file to transfer in bytes (default random)"
+	echo -e "\t-S: set sndbuf value (default: use kernel default)"
+	echo -e "\t-R: set rcvbuf value (default: use kernel default)"
+	echo -e "\t-m: test mode (poll, sendfile; default: poll)"
+	echo -e "\t-t: also run tests with TCP (use twice to non-fallback tcp)"
+	echo -e "\t-C: enable the MPTCP data checksum"
+}
+
+while getopts "$optstring" option;do
+	case "$option" in
+	"h")
+		usage $0
+		exit 0
+		;;
+	"d")
+		if [ $OPTARG -ge 0 ];then
+			tc_delay="$OPTARG"
+		else
+			echo "-d requires numeric argument, got \"$OPTARG\"" 1>&2
+			exit 1
+		fi
+		;;
+	"e")
+		ethtool_args="$ethtool_args $OPTARG off"
+		ethtool_random_on=false
+		;;
+	"l")
+		tc_loss="$OPTARG"
+		;;
+	"r")
+		tc_reorder="$OPTARG"
+		;;
+	"4")
+		ipv6=false
+		;;
+	"c")
+		capture=true
+		;;
+	"S")
+		if [ $OPTARG -ge 0 ];then
+			sndbuf="$OPTARG"
+		else
+			echo "-S requires numeric argument, got \"$OPTARG\"" 1>&2
+			exit 1
+		fi
+		;;
+	"R")
+		if [ $OPTARG -ge 0 ];then
+			rcvbuf="$OPTARG"
+		else
+			echo "-R requires numeric argument, got \"$OPTARG\"" 1>&2
+			exit 1
+		fi
+		;;
+	"m")
+		testmode="$OPTARG"
+		;;
+	"f")
+		filesize="$OPTARG"
+		;;
+	"t")
+		do_tcp=$((do_tcp+1))
+		;;
+	"C")
+		checksum=true
+		;;
+	"?")
+		usage $0
+		exit 1
+		;;
+	esac
+done
+
+sec=$(date +%s)
+rndh=$(printf %x $sec)-$(mktemp -u XXXXXX)
+ns1="ns1-$rndh"
+ns2="ns2-$rndh"
+ns3="ns3-$rndh"
+ns4="ns4-$rndh"
+
+TEST_COUNT=0
+
+cleanup()
+{
+	rm -f "$cin_disconnect" "$cout_disconnect"
+	rm -f "$cin" "$cout"
+	rm -f "$sin" "$sout"
+	rm -f "$capout"
+
+	local netns
+	for netns in "$ns1" "$ns2" "$ns3" "$ns4";do
+		ip netns del $netns
+		rm -f /tmp/$netns.{nstat,out}
+	done
+}
+
+mptcp_lib_check_mptcp
+mptcp_lib_check_kallsyms
+
+ip -Version > /dev/null 2>&1
+if [ $? -ne 0 ];then
+	echo "SKIP: Could not run test without ip tool"
+	exit $ksft_skip
+fi
+
+sin=$(mktemp)
+sout=$(mktemp)
+cin=$(mktemp)
+cout=$(mktemp)
+capout=$(mktemp)
+cin_disconnect="$cin".disconnect
+cout_disconnect="$cout".disconnect
+trap cleanup EXIT
+
+for i in "$ns1" "$ns2" "$ns3" "$ns4";do
+	ip netns add $i || exit $ksft_skip
+	ip -net $i link set lo up
+done
+
+#  "$ns1"              ns2                    ns3                     ns4
+# ns1eth2    ns2eth1   ns2eth3      ns3eth2   ns3eth4       ns4eth3
+#                           - drop 1% ->            reorder 25%
+#                           <- TSO off -
+
+ip link add ns1eth2 netns "$ns1" type veth peer name ns2eth1 netns "$ns2"
+ip link add ns2eth3 netns "$ns2" type veth peer name ns3eth2 netns "$ns3"
+ip link add ns3eth4 netns "$ns3" type veth peer name ns4eth3 netns "$ns4"
+
+ip -net "$ns1" addr add 10.0.1.1/24 dev ns1eth2
+ip -net "$ns1" addr add dead:beef:1::1/64 dev ns1eth2 nodad
+
+ip -net "$ns1" link set ns1eth2 up
+ip -net "$ns1" route add default via 10.0.1.2
+ip -net "$ns1" route add default via dead:beef:1::2
+
+ip -net "$ns2" addr add 10.0.1.2/24 dev ns2eth1
+ip -net "$ns2" addr add dead:beef:1::2/64 dev ns2eth1 nodad
+ip -net "$ns2" link set ns2eth1 up
+
+ip -net "$ns2" addr add 10.0.2.1/24 dev ns2eth3
+ip -net "$ns2" addr add dead:beef:2::1/64 dev ns2eth3 nodad
+ip -net "$ns2" link set ns2eth3 up
+ip -net "$ns2" route add default via 10.0.2.2
+ip -net "$ns2" route add default via dead:beef:2::2
+ip netns exec "$ns2" sysctl -q net.ipv4.ip_forward=1
+ip netns exec "$ns2" sysctl -q net.ipv6.conf.all.forwarding=1
+
+ip -net "$ns3" addr add 10.0.2.2/24 dev ns3eth2
+ip -net "$ns3" addr add dead:beef:2::2/64 dev ns3eth2 nodad
+ip -net "$ns3" link set ns3eth2 up
+
+ip -net "$ns3" addr add 10.0.3.2/24 dev ns3eth4
+ip -net "$ns3" addr add dead:beef:3::2/64 dev ns3eth4 nodad
+ip -net "$ns3" link set ns3eth4 up
+ip -net "$ns3" route add default via 10.0.2.1
+ip -net "$ns3" route add default via dead:beef:2::1
+ip netns exec "$ns3" sysctl -q net.ipv4.ip_forward=1
+ip netns exec "$ns3" sysctl -q net.ipv6.conf.all.forwarding=1
+
+ip -net "$ns4" addr add 10.0.3.1/24 dev ns4eth3
+ip -net "$ns4" addr add dead:beef:3::1/64 dev ns4eth3 nodad
+ip -net "$ns4" link set ns4eth3 up
+ip -net "$ns4" route add default via 10.0.3.2
+ip -net "$ns4" route add default via dead:beef:3::2
+
+if $checksum; then
+	for i in "$ns1" "$ns2" "$ns3" "$ns4";do
+		ip netns exec $i sysctl -q net.mptcp.checksum_enabled=1
+	done
+fi
+
+set_ethtool_flags() {
+	local ns="$1"
+	local dev="$2"
+	local flags="$3"
+
+	ip netns exec $ns ethtool -K $dev $flags 2>/dev/null
+	[ $? -eq 0 ] && echo "INFO: set $ns dev $dev: ethtool -K $flags"
+}
+
+set_random_ethtool_flags() {
+	local flags=""
+	local r=$RANDOM
+
+	local pick1=$((r & 1))
+	local pick2=$((r & 2))
+	local pick3=$((r & 4))
+
+	[ $pick1 -ne 0 ] && flags="tso off"
+	[ $pick2 -ne 0 ] && flags="$flags gso off"
+	[ $pick3 -ne 0 ] && flags="$flags gro off"
+
+	[ -z "$flags" ] && return
+
+	set_ethtool_flags "$1" "$2" "$flags"
+}
+
+if $ethtool_random_on;then
+	set_random_ethtool_flags "$ns3" ns3eth2
+	set_random_ethtool_flags "$ns4" ns4eth3
+else
+	set_ethtool_flags "$ns3" ns3eth2 "$ethtool_args"
+	set_ethtool_flags "$ns4" ns4eth3 "$ethtool_args"
+fi
+
+print_file_err()
+{
+	ls -l "$1" 1>&2
+	echo "Trailing bytes are: "
+	tail -c 27 "$1"
+}
+
+check_transfer()
+{
+	local in=$1
+	local out=$2
+	local what=$3
+
+	cmp "$in" "$out" > /dev/null 2>&1
+	if [ $? -ne 0 ] ;then
+		echo "[ FAIL ] $what does not match (in, out):"
+		print_file_err "$in"
+		print_file_err "$out"
+
+		return 1
+	fi
+
+	return 0
+}
+
+check_mptcp_disabled()
+{
+	local disabled_ns
+	disabled_ns="ns_disabled-$sech-$(mktemp -u XXXXXX)"
+	ip netns add ${disabled_ns} || exit $ksft_skip
+
+	# net.mptcp.enabled should be enabled by default
+	if [ "$(ip netns exec ${disabled_ns} sysctl net.mptcp.enabled | awk '{ print $3 }')" -ne 1 ]; then
+		echo -e "net.mptcp.enabled sysctl is not 1 by default\t\t[ FAIL ]"
+		ret=1
+		return 1
+	fi
+	ip netns exec ${disabled_ns} sysctl -q net.mptcp.enabled=0
+
+	local err=0
+	LC_ALL=C ip netns exec ${disabled_ns} ./mptcp_connect -p 10000 -s MPTCP 127.0.0.1 < "$cin" 2>&1 | \
+		grep -q "^socket: Protocol not available$" && err=1
+	ip netns delete ${disabled_ns}
+
+	if [ ${err} -eq 0 ]; then
+		echo -e "New MPTCP socket cannot be blocked via sysctl\t\t[ FAIL ]"
+		ret=1
+		return 1
+	fi
+
+	echo -e "New MPTCP socket can be blocked via sysctl\t\t[ OK ]"
+	return 0
+}
+
+# $1: IP address
+is_v6()
+{
+	[ -z "${1##*:*}" ]
+}
+
+do_ping()
+{
+	local listener_ns="$1"
+	local connector_ns="$2"
+	local connect_addr="$3"
+	local ping_args="-q -c 1"
+
+	if is_v6 "${connect_addr}"; then
+		$ipv6 || return 0
+		ping_args="${ping_args} -6"
+	fi
+
+	ip netns exec ${connector_ns} ping ${ping_args} $connect_addr >/dev/null
+	if [ $? -ne 0 ] ; then
+		echo "$listener_ns -> $connect_addr connectivity [ FAIL ]" 1>&2
+		ret=1
+
+		return 1
+	fi
+
+	return 0
+}
+
+# $1: ns, $2: MIB counter
+get_mib_counter()
+{
+	local listener_ns="${1}"
+	local mib="${2}"
+
+	# strip the header
+	ip netns exec "${listener_ns}" \
+		nstat -z -a "${mib}" | \
+			tail -n+2 | \
+			while read a count c rest; do
+				echo $count
+			done
+}
+
+# $1: ns, $2: port
+wait_local_port_listen()
+{
+	local listener_ns="${1}"
+	local port="${2}"
+
+	local port_hex i
+
+	port_hex="$(printf "%04X" "${port}")"
+	for i in $(seq 10); do
+		ip netns exec "${listener_ns}" cat /proc/net/tcp* | \
+			awk "BEGIN {rc=1} {if (\$2 ~ /:${port_hex}\$/ && \$4 ~ /0A/) {rc=0; exit}} END {exit rc}" &&
+			break
+		sleep 0.1
+	done
+}
+
+do_transfer()
+{
+	local listener_ns="$1"
+	local connector_ns="$2"
+	local cl_proto="$3"
+	local srv_proto="$4"
+	local connect_addr="$5"
+	local local_addr="$6"
+	local extra_args="$7"
+
+	local port
+	port=$((10000+$TEST_COUNT))
+	TEST_COUNT=$((TEST_COUNT+1))
+
+	if [ "$rcvbuf" -gt 0 ]; then
+		extra_args="$extra_args -R $rcvbuf"
+	fi
+
+	if [ "$sndbuf" -gt 0 ]; then
+		extra_args="$extra_args -S $sndbuf"
+	fi
+
+	if [ -n "$testmode" ]; then
+		extra_args="$extra_args -m $testmode"
+	fi
+
+	if [ -n "$extra_args" ] && $options_log; then
+		echo "INFO: extra options: $extra_args"
+	fi
+	options_log=false
+
+	:> "$cout"
+	:> "$sout"
+	:> "$capout"
+
+	local addr_port
+	addr_port=$(printf "%s:%d" ${connect_addr} ${port})
+	printf "%.3s %-5s -> %.3s (%-20s) %-5s\t" ${connector_ns} ${cl_proto} ${listener_ns} ${addr_port} ${srv_proto}
+
+	if $capture; then
+		local capuser
+		if [ -z $SUDO_USER ] ; then
+			capuser=""
+		else
+			capuser="-Z $SUDO_USER"
+		fi
+
+		local capfile="${rndh}-${connector_ns:0:3}-${listener_ns:0:3}-${cl_proto}-${srv_proto}-${connect_addr}-${port}"
+		local capopt="-i any -s 65535 -B 32768 ${capuser}"
+
+		ip netns exec ${listener_ns}  tcpdump ${capopt} -w "${capfile}-listener.pcap"  >> "${capout}" 2>&1 &
+		local cappid_listener=$!
+
+		ip netns exec ${connector_ns} tcpdump ${capopt} -w "${capfile}-connector.pcap" >> "${capout}" 2>&1 &
+		local cappid_connector=$!
+
+		sleep 1
+	fi
+
+	NSTAT_HISTORY=/tmp/${listener_ns}.nstat ip netns exec ${listener_ns} \
+		nstat -n
+	if [ ${listener_ns} != ${connector_ns} ]; then
+		NSTAT_HISTORY=/tmp/${connector_ns}.nstat ip netns exec ${connector_ns} \
+			nstat -n
+	fi
+
+	local stat_synrx_last_l=$(get_mib_counter "${listener_ns}" "MPTcpExtMPCapableSYNRX")
+	local stat_ackrx_last_l=$(get_mib_counter "${listener_ns}" "MPTcpExtMPCapableACKRX")
+	local stat_cookietx_last=$(get_mib_counter "${listener_ns}" "TcpExtSyncookiesSent")
+	local stat_cookierx_last=$(get_mib_counter "${listener_ns}" "TcpExtSyncookiesRecv")
+	local stat_csum_err_s=$(get_mib_counter "${listener_ns}" "MPTcpExtDataCsumErr")
+	local stat_csum_err_c=$(get_mib_counter "${connector_ns}" "MPTcpExtDataCsumErr")
+
+	timeout ${timeout_test} \
+		ip netns exec ${listener_ns} \
+			./mptcp_connect -t ${timeout_poll} -l -p $port -s ${srv_proto} \
+				$extra_args $local_addr < "$sin" > "$sout" &
+	local spid=$!
+
+	wait_local_port_listen "${listener_ns}" "${port}"
+
+	local start
+	start=$(date +%s%3N)
+	timeout ${timeout_test} \
+		ip netns exec ${connector_ns} \
+			./mptcp_connect -t ${timeout_poll} -p $port -s ${cl_proto} \
+				$extra_args $connect_addr < "$cin" > "$cout" &
+	local cpid=$!
+
+	wait $cpid
+	local retc=$?
+	wait $spid
+	local rets=$?
+
+	local stop
+	stop=$(date +%s%3N)
+
+	if $capture; then
+		sleep 1
+		kill ${cappid_listener}
+		kill ${cappid_connector}
+	fi
+
+	NSTAT_HISTORY=/tmp/${listener_ns}.nstat ip netns exec ${listener_ns} \
+		nstat | grep Tcp > /tmp/${listener_ns}.out
+	if [ ${listener_ns} != ${connector_ns} ]; then
+		NSTAT_HISTORY=/tmp/${connector_ns}.nstat ip netns exec ${connector_ns} \
+			nstat | grep Tcp > /tmp/${connector_ns}.out
+	fi
+
+	local duration
+	duration=$((stop-start))
+	printf "(duration %05sms) " "${duration}"
+	if [ ${rets} -ne 0 ] || [ ${retc} -ne 0 ]; then
+		echo "[ FAIL ] client exit code $retc, server $rets" 1>&2
+		echo -e "\nnetns ${listener_ns} socket stat for ${port}:" 1>&2
+		ip netns exec ${listener_ns} ss -Menita 1>&2 -o "sport = :$port"
+		cat /tmp/${listener_ns}.out
+		echo -e "\nnetns ${connector_ns} socket stat for ${port}:" 1>&2
+		ip netns exec ${connector_ns} ss -Menita 1>&2 -o "dport = :$port"
+		[ ${listener_ns} != ${connector_ns} ] && cat /tmp/${connector_ns}.out
+
+		echo
+		cat "$capout"
+		return 1
+	fi
+
+	check_transfer $sin $cout "file received by client"
+	retc=$?
+	check_transfer $cin $sout "file received by server"
+	rets=$?
+
+	local stat_synrx_now_l=$(get_mib_counter "${listener_ns}" "MPTcpExtMPCapableSYNRX")
+	local stat_ackrx_now_l=$(get_mib_counter "${listener_ns}" "MPTcpExtMPCapableACKRX")
+	local stat_cookietx_now=$(get_mib_counter "${listener_ns}" "TcpExtSyncookiesSent")
+	local stat_cookierx_now=$(get_mib_counter "${listener_ns}" "TcpExtSyncookiesRecv")
+	local stat_ooo_now=$(get_mib_counter "${listener_ns}" "TcpExtTCPOFOQueue")
+
+	expect_synrx=$((stat_synrx_last_l))
+	expect_ackrx=$((stat_ackrx_last_l))
+
+	cookies=$(ip netns exec ${listener_ns} sysctl net.ipv4.tcp_syncookies)
+	cookies=${cookies##*=}
+
+	if [ ${cl_proto} = "MPTCP" ] && [ ${srv_proto} = "MPTCP" ]; then
+		expect_synrx=$((stat_synrx_last_l+$connect_per_transfer))
+		expect_ackrx=$((stat_ackrx_last_l+$connect_per_transfer))
+	fi
+
+	if [ ${stat_synrx_now_l} -lt ${expect_synrx} ]; then
+		printf "[ FAIL ] lower MPC SYN rx (%d) than expected (%d)\n" \
+			"${stat_synrx_now_l}" "${expect_synrx}" 1>&2
+		retc=1
+	fi
+	if [ ${stat_ackrx_now_l} -lt ${expect_ackrx} -a ${stat_ooo_now} -eq 0 ]; then
+		if [ ${stat_ooo_now} -eq 0 ]; then
+			printf "[ FAIL ] lower MPC ACK rx (%d) than expected (%d)\n" \
+				"${stat_ackrx_now_l}" "${expect_ackrx}" 1>&2
+			rets=1
+		else
+			printf "[ Note ] fallback due to TCP OoO"
+		fi
+	fi
+
+	if $checksum; then
+		local csum_err_s=$(get_mib_counter "${listener_ns}" "MPTcpExtDataCsumErr")
+		local csum_err_c=$(get_mib_counter "${connector_ns}" "MPTcpExtDataCsumErr")
+
+		local csum_err_s_nr=$((csum_err_s - stat_csum_err_s))
+		if [ $csum_err_s_nr -gt 0 ]; then
+			printf "[ FAIL ]\nserver got $csum_err_s_nr data checksum error[s]"
+			rets=1
+		fi
+
+		local csum_err_c_nr=$((csum_err_c - stat_csum_err_c))
+		if [ $csum_err_c_nr -gt 0 ]; then
+			printf "[ FAIL ]\nclient got $csum_err_c_nr data checksum error[s]"
+			retc=1
+		fi
+	fi
+
+	if [ $retc -eq 0 ] && [ $rets -eq 0 ]; then
+		printf "[ OK ]"
+	fi
+
+	if [ $cookies -eq 2 ];then
+		if [ $stat_cookietx_last -ge $stat_cookietx_now ] ;then
+			printf " WARN: CookieSent: did not advance"
+		fi
+		if [ $stat_cookierx_last -ge $stat_cookierx_now ] ;then
+			printf " WARN: CookieRecv: did not advance"
+		fi
+	else
+		if [ $stat_cookietx_last -ne $stat_cookietx_now ] ;then
+			printf " WARN: CookieSent: changed"
+		fi
+		if [ $stat_cookierx_last -ne $stat_cookierx_now ] ;then
+			printf " WARN: CookieRecv: changed"
+		fi
+	fi
+
+	if [ ${stat_synrx_now_l} -gt ${expect_synrx} ]; then
+		printf " WARN: SYNRX: expect %d, got %d (probably retransmissions)" \
+			"${expect_synrx}" "${stat_synrx_now_l}"
+	fi
+	if [ ${stat_ackrx_now_l} -gt ${expect_ackrx} ]; then
+		printf " WARN: ACKRX: expect %d, got %d (probably retransmissions)" \
+			"${expect_ackrx}" "${stat_ackrx_now_l}"
+	fi
+
+	echo
+	cat "$capout"
+	[ $retc -eq 0 ] && [ $rets -eq 0 ]
+}
+
+make_file()
+{
+	local name=$1
+	local who=$2
+	local SIZE=$filesize
+	local ksize
+	local rem
+
+	if [ $SIZE -eq 0 ]; then
+		local MAXSIZE=$((1024 * 1024 * 8))
+		local MINSIZE=$((1024 * 256))
+
+		SIZE=$(((RANDOM * RANDOM + MINSIZE) % MAXSIZE))
+	fi
+
+	ksize=$((SIZE / 1024))
+	rem=$((SIZE - (ksize * 1024)))
+
+	dd if=/dev/urandom of="$name" bs=1024 count=$ksize 2> /dev/null
+	dd if=/dev/urandom conv=notrunc of="$name" bs=1 count=$rem 2> /dev/null
+	echo -e "\nMPTCP_TEST_FILE_END_MARKER" >> "$name"
+
+	echo "Created $name (size $(du -b "$name")) containing data sent by $who"
+}
+
+run_tests_lo()
+{
+	local listener_ns="$1"
+	local connector_ns="$2"
+	local connect_addr="$3"
+	local loopback="$4"
+	local extra_args="$5"
+	local lret=0
+
+	# skip if test programs are running inside same netns for subsequent runs.
+	if [ $loopback -eq 0 ] && [ ${listener_ns} = ${connector_ns} ]; then
+		return 0
+	fi
+
+	# skip if we don't want v6
+	if ! $ipv6 && is_v6 "${connect_addr}"; then
+		return 0
+	fi
+
+	local local_addr
+	if is_v6 "${connect_addr}"; then
+		local_addr="::"
+	else
+		local_addr="0.0.0.0"
+	fi
+
+	do_transfer ${listener_ns} ${connector_ns} MPTCP MPTCP \
+		    ${connect_addr} ${local_addr} "${extra_args}"
+	lret=$?
+	if [ $lret -ne 0 ]; then
+		ret=$lret
+		return 1
+	fi
+
+	if [ $do_tcp -eq 0 ]; then
+		# don't bother testing fallback tcp except for loopback case.
+		if [ ${listener_ns} != ${connector_ns} ]; then
+			return 0
+		fi
+	fi
+
+	do_transfer ${listener_ns} ${connector_ns} MPTCP TCP \
+		    ${connect_addr} ${local_addr} "${extra_args}"
+	lret=$?
+	if [ $lret -ne 0 ]; then
+		ret=$lret
+		return 1
+	fi
+
+	do_transfer ${listener_ns} ${connector_ns} TCP MPTCP \
+		    ${connect_addr} ${local_addr} "${extra_args}"
+	lret=$?
+	if [ $lret -ne 0 ]; then
+		ret=$lret
+		return 1
+	fi
+
+	if [ $do_tcp -gt 1 ] ;then
+		do_transfer ${listener_ns} ${connector_ns} TCP TCP \
+			    ${connect_addr} ${local_addr} "${extra_args}"
+		lret=$?
+		if [ $lret -ne 0 ]; then
+			ret=$lret
+			return 1
+		fi
+	fi
+
+	return 0
+}
+
+run_tests()
+{
+	run_tests_lo $1 $2 $3 0
+}
+
+run_test_transparent()
+{
+	local connect_addr="$1"
+	local msg="$2"
+
+	local connector_ns="$ns1"
+	local listener_ns="$ns2"
+	local lret=0
+	local r6flag=""
+
+	# skip if we don't want v6
+	if ! $ipv6 && is_v6 "${connect_addr}"; then
+		return 0
+	fi
+
+	# IP(V6)_TRANSPARENT has been added after TOS support which came with
+	# the required infrastructure in MPTCP sockopt code. To support TOS, the
+	# following function has been exported (T). Not great but better than
+	# checking for a specific kernel version.
+	if ! mptcp_lib_kallsyms_has "T __ip_sock_set_tos$"; then
+		echo "INFO: ${msg} not supported by the kernel: SKIP"
+		return
+	fi
+
+ip netns exec "$listener_ns" nft -f /dev/stdin <<"EOF"
+flush ruleset
+table inet mangle {
+	chain divert {
+		type filter hook prerouting priority -150;
+
+		meta l4proto tcp socket transparent 1 meta mark set 1 accept
+		tcp dport 20000 tproxy to :20000 meta mark set 1 accept
+	}
+}
+EOF
+	if [ $? -ne 0 ]; then
+		echo "SKIP: $msg, could not load nft ruleset"
+		mptcp_lib_fail_if_expected_feature "nft rules"
+		return
+	fi
+
+	local local_addr
+	if is_v6 "${connect_addr}"; then
+		local_addr="::"
+		r6flag="-6"
+	else
+		local_addr="0.0.0.0"
+	fi
+
+	ip -net "$listener_ns" $r6flag rule add fwmark 1 lookup 100
+	if [ $? -ne 0 ]; then
+		ip netns exec "$listener_ns" nft flush ruleset
+		echo "SKIP: $msg, ip $r6flag rule failed"
+		mptcp_lib_fail_if_expected_feature "ip rule"
+		return
+	fi
+
+	ip -net "$listener_ns" route add local $local_addr/0 dev lo table 100
+	if [ $? -ne 0 ]; then
+		ip netns exec "$listener_ns" nft flush ruleset
+		ip -net "$listener_ns" $r6flag rule del fwmark 1 lookup 100
+		echo "SKIP: $msg, ip route add local $local_addr failed"
+		mptcp_lib_fail_if_expected_feature "ip route"
+		return
+	fi
+
+	echo "INFO: test $msg"
+
+	TEST_COUNT=10000
+	local extra_args="-o TRANSPARENT"
+	do_transfer ${listener_ns} ${connector_ns} MPTCP MPTCP \
+		    ${connect_addr} ${local_addr} "${extra_args}"
+	lret=$?
+
+	ip netns exec "$listener_ns" nft flush ruleset
+	ip -net "$listener_ns" $r6flag rule del fwmark 1 lookup 100
+	ip -net "$listener_ns" route del local $local_addr/0 dev lo table 100
+
+	if [ $lret -ne 0 ]; then
+		echo "FAIL: $msg, mptcp connection error" 1>&2
+		ret=$lret
+		return 1
+	fi
+
+	echo "PASS: $msg"
+	return 0
+}
+
+run_tests_peekmode()
+{
+	local peekmode="$1"
+
+	echo "INFO: with peek mode: ${peekmode}"
+	run_tests_lo "$ns1" "$ns1" 10.0.1.1 1 "-P ${peekmode}"
+	run_tests_lo "$ns1" "$ns1" dead:beef:1::1 1 "-P ${peekmode}"
+}
+
+run_tests_disconnect()
+{
+	local peekmode="$1"
+	local old_cin=$cin
+	local old_sin=$sin
+
+	if ! mptcp_lib_kallsyms_has "mptcp_pm_data_reset$"; then
+		echo "INFO: Full disconnect not supported: SKIP"
+		return
+	fi
+
+	cat $cin $cin $cin > "$cin".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
+
+	echo "INFO: disconnect"
+	run_tests_lo "$ns1" "$ns1" 10.0.1.1 1 "-I 3 -i $old_cin"
+	run_tests_lo "$ns1" "$ns1" dead:beef:1::1 1 "-I 3 -i $old_cin"
+
+	# restore previous status
+	sin=$old_sin
+	sin_disconnect="$cout".disconnect
+	cin=$old_cin
+	cin_disconnect="$cin".disconnect
+	connect_per_transfer=1
+}
+
+display_time()
+{
+	time_end=$(date +%s)
+	time_run=$((time_end-time_start))
+
+	echo "Time: ${time_run} seconds"
+}
+
+stop_if_error()
+{
+	local msg="$1"
+
+	if [ ${ret} -ne 0 ]; then
+		echo "FAIL: ${msg}" 1>&2
+		display_time
+		exit ${ret}
+	fi
+}
+
+make_file "$cin" "client"
+make_file "$sin" "server"
+
+check_mptcp_disabled
+
+stop_if_error "The kernel configuration is not valid for MPTCP"
+
+echo "INFO: validating network environment with pings"
+for sender in "$ns1" "$ns2" "$ns3" "$ns4";do
+	do_ping "$ns1" $sender 10.0.1.1
+	do_ping "$ns1" $sender dead:beef:1::1
+
+	do_ping "$ns2" $sender 10.0.1.2
+	do_ping "$ns2" $sender dead:beef:1::2
+	do_ping "$ns2" $sender 10.0.2.1
+	do_ping "$ns2" $sender dead:beef:2::1
+
+	do_ping "$ns3" $sender 10.0.2.2
+	do_ping "$ns3" $sender dead:beef:2::2
+	do_ping "$ns3" $sender 10.0.3.2
+	do_ping "$ns3" $sender dead:beef:3::2
+
+	do_ping "$ns4" $sender 10.0.3.1
+	do_ping "$ns4" $sender dead:beef:3::1
+done
+
+stop_if_error "Could not even run ping tests"
+
+[ -n "$tc_loss" ] && tc -net "$ns2" qdisc add dev ns2eth3 root netem loss random $tc_loss delay ${tc_delay}ms
+echo -n "INFO: Using loss of $tc_loss "
+test "$tc_delay" -gt 0 && echo -n "delay $tc_delay ms "
+
+reorder_delay=$(($tc_delay / 4))
+
+if [ -z "${tc_reorder}" ]; then
+	reorder1=$((RANDOM%10))
+	reorder1=$((100 - reorder1))
+	reorder2=$((RANDOM%100))
+
+	if [ $reorder_delay -gt 0 ] && [ $reorder1 -lt 100 ] && [ $reorder2 -gt 0 ]; then
+		tc_reorder="reorder ${reorder1}% ${reorder2}%"
+		echo -n "$tc_reorder with delay ${reorder_delay}ms "
+	fi
+elif [ "$tc_reorder" = "0" ];then
+	tc_reorder=""
+elif [ "$reorder_delay" -gt 0 ];then
+	# reordering requires some delay
+	tc_reorder="reorder $tc_reorder"
+	echo -n "$tc_reorder with delay ${reorder_delay}ms "
+fi
+
+echo "on ns3eth4"
+
+tc -net "$ns3" qdisc add dev ns3eth4 root netem delay ${reorder_delay}ms $tc_reorder
+
+run_tests_lo "$ns1" "$ns1" 10.0.1.1 1
+stop_if_error "Could not even run loopback test"
+
+run_tests_lo "$ns1" "$ns1" dead:beef:1::1 1
+stop_if_error "Could not even run loopback v6 test"
+
+for sender in $ns1 $ns2 $ns3 $ns4;do
+	# ns1<->ns2 is not subject to reordering/tc delays. Use it to test
+	# mptcp syncookie support.
+	if [ $sender = $ns1 ]; then
+		ip netns exec "$ns2" sysctl -q net.ipv4.tcp_syncookies=2
+	else
+		ip netns exec "$ns2" sysctl -q net.ipv4.tcp_syncookies=1
+	fi
+
+	run_tests "$ns1" $sender 10.0.1.1
+	run_tests "$ns1" $sender dead:beef:1::1
+
+	run_tests "$ns2" $sender 10.0.1.2
+	run_tests "$ns2" $sender dead:beef:1::2
+	run_tests "$ns2" $sender 10.0.2.1
+	run_tests "$ns2" $sender dead:beef:2::1
+
+	run_tests "$ns3" $sender 10.0.2.2
+	run_tests "$ns3" $sender dead:beef:2::2
+	run_tests "$ns3" $sender 10.0.3.2
+	run_tests "$ns3" $sender dead:beef:3::2
+
+	run_tests "$ns4" $sender 10.0.3.1
+	run_tests "$ns4" $sender dead:beef:3::1
+
+	stop_if_error "Tests with $sender as a sender have failed"
+done
+
+run_tests_peekmode "saveWithPeek"
+run_tests_peekmode "saveAfterPeek"
+stop_if_error "Tests with peek mode have failed"
+
+# connect to ns4 ip address, ns2 should intercept/proxy
+run_test_transparent 10.0.3.1 "tproxy ipv4"
+run_test_transparent dead:beef:3::1 "tproxy ipv6"
+stop_if_error "Tests with tproxy have failed"
+
+run_tests_disconnect
+
+display_time
+exit $ret
diff --git a/tools/testing/selftests/net/mptcp/mptcp_inq.c b/tools/testing/selftests/net/mptcp/mptcp_inq.c
new file mode 100644
index 000000000..218aac467
--- /dev/null
+++ b/tools/testing/selftests/net/mptcp/mptcp_inq.c
@@ -0,0 +1,599 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#define _GNU_SOURCE
+
+#include <assert.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <string.h>
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <inttypes.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <strings.h>
+#include <unistd.h>
+#include <time.h>
+
+#include <sys/ioctl.h>
+#include <sys/random.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+
+#include <netdb.h>
+#include <netinet/in.h>
+
+#include <linux/tcp.h>
+#include <linux/sockios.h>
+
+#ifndef IPPROTO_MPTCP
+#define IPPROTO_MPTCP 262
+#endif
+#ifndef SOL_MPTCP
+#define SOL_MPTCP 284
+#endif
+
+static int pf = AF_INET;
+static int proto_tx = IPPROTO_MPTCP;
+static int proto_rx = IPPROTO_MPTCP;
+
+static void die_perror(const char *msg)
+{
+	perror(msg);
+	exit(1);
+}
+
+static void die_usage(int r)
+{
+	fprintf(stderr, "Usage: mptcp_inq [-6] [ -t tcp|mptcp ] [ -r tcp|mptcp]\n");
+	exit(r);
+}
+
+static void xerror(const char *fmt, ...)
+{
+	va_list ap;
+
+	va_start(ap, fmt);
+	vfprintf(stderr, fmt, ap);
+	va_end(ap);
+	fputc('\n', stderr);
+	exit(1);
+}
+
+static const char *getxinfo_strerr(int err)
+{
+	if (err == EAI_SYSTEM)
+		return strerror(errno);
+
+	return gai_strerror(err);
+}
+
+static void xgetaddrinfo(const char *node, const char *service,
+			 const struct addrinfo *hints,
+			 struct addrinfo **res)
+{
+	int err = getaddrinfo(node, service, hints, res);
+
+	if (err) {
+		const char *errstr = getxinfo_strerr(err);
+
+		fprintf(stderr, "Fatal: getaddrinfo(%s:%s): %s\n",
+			node ? node : "", service ? service : "", errstr);
+		exit(1);
+	}
+}
+
+static int sock_listen_mptcp(const char * const listenaddr,
+			     const char * const port)
+{
+	int sock = -1;
+	struct addrinfo hints = {
+		.ai_protocol = IPPROTO_TCP,
+		.ai_socktype = SOCK_STREAM,
+		.ai_flags = AI_PASSIVE | AI_NUMERICHOST
+	};
+
+	hints.ai_family = pf;
+
+	struct addrinfo *a, *addr;
+	int one = 1;
+
+	xgetaddrinfo(listenaddr, port, &hints, &addr);
+	hints.ai_family = pf;
+
+	for (a = addr; a; a = a->ai_next) {
+		sock = socket(a->ai_family, a->ai_socktype, proto_rx);
+		if (sock < 0)
+			continue;
+
+		if (-1 == setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &one,
+				     sizeof(one)))
+			perror("setsockopt");
+
+		if (bind(sock, a->ai_addr, a->ai_addrlen) == 0)
+			break; /* success */
+
+		perror("bind");
+		close(sock);
+		sock = -1;
+	}
+
+	freeaddrinfo(addr);
+
+	if (sock < 0)
+		xerror("could not create listen socket");
+
+	if (listen(sock, 20))
+		die_perror("listen");
+
+	return sock;
+}
+
+static int sock_connect_mptcp(const char * const remoteaddr,
+			      const char * const port, int proto)
+{
+	struct addrinfo hints = {
+		.ai_protocol = IPPROTO_TCP,
+		.ai_socktype = SOCK_STREAM,
+	};
+	struct addrinfo *a, *addr;
+	int sock = -1;
+
+	hints.ai_family = pf;
+
+	xgetaddrinfo(remoteaddr, port, &hints, &addr);
+	for (a = addr; a; a = a->ai_next) {
+		sock = socket(a->ai_family, a->ai_socktype, proto);
+		if (sock < 0)
+			continue;
+
+		if (connect(sock, a->ai_addr, a->ai_addrlen) == 0)
+			break; /* success */
+
+		die_perror("connect");
+	}
+
+	if (sock < 0)
+		xerror("could not create connect socket");
+
+	freeaddrinfo(addr);
+	return sock;
+}
+
+static int protostr_to_num(const char *s)
+{
+	if (strcasecmp(s, "tcp") == 0)
+		return IPPROTO_TCP;
+	if (strcasecmp(s, "mptcp") == 0)
+		return IPPROTO_MPTCP;
+
+	die_usage(1);
+	return 0;
+}
+
+static void parse_opts(int argc, char **argv)
+{
+	int c;
+
+	while ((c = getopt(argc, argv, "h6t:r:")) != -1) {
+		switch (c) {
+		case 'h':
+			die_usage(0);
+			break;
+		case '6':
+			pf = AF_INET6;
+			break;
+		case 't':
+			proto_tx = protostr_to_num(optarg);
+			break;
+		case 'r':
+			proto_rx = protostr_to_num(optarg);
+			break;
+		default:
+			die_usage(1);
+			break;
+		}
+	}
+}
+
+/* wait up to timeout milliseconds */
+static void wait_for_ack(int fd, int timeout, size_t total)
+{
+	int i;
+
+	for (i = 0; i < timeout; i++) {
+		int nsd, ret, queued = -1;
+		struct timespec req;
+
+		ret = ioctl(fd, TIOCOUTQ, &queued);
+		if (ret < 0)
+			die_perror("TIOCOUTQ");
+
+		ret = ioctl(fd, SIOCOUTQNSD, &nsd);
+		if (ret < 0)
+			die_perror("SIOCOUTQNSD");
+
+		if ((size_t)queued > total)
+			xerror("TIOCOUTQ %u, but only %zu expected\n", queued, total);
+		assert(nsd <= queued);
+
+		if (queued == 0)
+			return;
+
+		/* wait for peer to ack rx of all data */
+		req.tv_sec = 0;
+		req.tv_nsec = 1 * 1000 * 1000ul; /* 1ms */
+		nanosleep(&req, NULL);
+	}
+
+	xerror("still tx data queued after %u ms\n", timeout);
+}
+
+static void connect_one_server(int fd, int unixfd)
+{
+	size_t len, i, total, sent;
+	char buf[4096], buf2[4096];
+	ssize_t ret;
+
+	len = rand() % (sizeof(buf) - 1);
+
+	if (len < 128)
+		len = 128;
+
+	for (i = 0; i < len ; i++) {
+		buf[i] = rand() % 26;
+		buf[i] += 'A';
+	}
+
+	buf[i] = '\n';
+
+	/* un-block server */
+	ret = read(unixfd, buf2, 4);
+	assert(ret == 4);
+
+	assert(strncmp(buf2, "xmit", 4) == 0);
+
+	ret = write(unixfd, &len, sizeof(len));
+	assert(ret == (ssize_t)sizeof(len));
+
+	ret = write(fd, buf, len);
+	if (ret < 0)
+		die_perror("write");
+
+	if (ret != (ssize_t)len)
+		xerror("short write");
+
+	ret = read(unixfd, buf2, 4);
+	assert(strncmp(buf2, "huge", 4) == 0);
+
+	total = rand() % (16 * 1024 * 1024);
+	total += (1 * 1024 * 1024);
+	sent = total;
+
+	ret = write(unixfd, &total, sizeof(total));
+	assert(ret == (ssize_t)sizeof(total));
+
+	wait_for_ack(fd, 5000, len);
+
+	while (total > 0) {
+		if (total > sizeof(buf))
+			len = sizeof(buf);
+		else
+			len = total;
+
+		ret = write(fd, buf, len);
+		if (ret < 0)
+			die_perror("write");
+		total -= ret;
+
+		/* we don't have to care about buf content, only
+		 * number of total bytes sent
+		 */
+	}
+
+	ret = read(unixfd, buf2, 4);
+	assert(ret == 4);
+	assert(strncmp(buf2, "shut", 4) == 0);
+
+	wait_for_ack(fd, 5000, sent);
+
+	ret = write(fd, buf, 1);
+	assert(ret == 1);
+	close(fd);
+	ret = write(unixfd, "closed", 6);
+	assert(ret == 6);
+
+	close(unixfd);
+}
+
+static void get_tcp_inq(struct msghdr *msgh, unsigned int *inqv)
+{
+	struct cmsghdr *cmsg;
+
+	for (cmsg = CMSG_FIRSTHDR(msgh); cmsg ; cmsg = CMSG_NXTHDR(msgh, cmsg)) {
+		if (cmsg->cmsg_level == IPPROTO_TCP && cmsg->cmsg_type == TCP_CM_INQ) {
+			memcpy(inqv, CMSG_DATA(cmsg), sizeof(*inqv));
+			return;
+		}
+	}
+
+	xerror("could not find TCP_CM_INQ cmsg type");
+}
+
+static void process_one_client(int fd, int unixfd)
+{
+	unsigned int tcp_inq;
+	size_t expect_len;
+	char msg_buf[4096];
+	char buf[4096];
+	char tmp[16];
+	struct iovec iov = {
+		.iov_base = buf,
+		.iov_len = 1,
+	};
+	struct msghdr msg = {
+		.msg_iov = &iov,
+		.msg_iovlen = 1,
+		.msg_control = msg_buf,
+		.msg_controllen = sizeof(msg_buf),
+	};
+	ssize_t ret, tot;
+
+	ret = write(unixfd, "xmit", 4);
+	assert(ret == 4);
+
+	ret = read(unixfd, &expect_len, sizeof(expect_len));
+	assert(ret == (ssize_t)sizeof(expect_len));
+
+	if (expect_len > sizeof(buf))
+		xerror("expect len %zu exceeds buffer size", expect_len);
+
+	for (;;) {
+		struct timespec req;
+		unsigned int queued;
+
+		ret = ioctl(fd, FIONREAD, &queued);
+		if (ret < 0)
+			die_perror("FIONREAD");
+		if (queued > expect_len)
+			xerror("FIONREAD returned %u, but only %zu expected\n",
+			       queued, expect_len);
+		if (queued == expect_len)
+			break;
+
+		req.tv_sec = 0;
+		req.tv_nsec = 1000 * 1000ul;
+		nanosleep(&req, NULL);
+	}
+
+	/* read one byte, expect cmsg to return expected - 1 */
+	ret = recvmsg(fd, &msg, 0);
+	if (ret < 0)
+		die_perror("recvmsg");
+
+	if (msg.msg_controllen == 0)
+		xerror("msg_controllen is 0");
+
+	get_tcp_inq(&msg, &tcp_inq);
+
+	assert((size_t)tcp_inq == (expect_len - 1));
+
+	iov.iov_len = sizeof(buf);
+	ret = recvmsg(fd, &msg, 0);
+	if (ret < 0)
+		die_perror("recvmsg");
+
+	/* should have gotten exact remainder of all pending data */
+	assert(ret == (ssize_t)tcp_inq);
+
+	/* should be 0, all drained */
+	get_tcp_inq(&msg, &tcp_inq);
+	assert(tcp_inq == 0);
+
+	/* request a large swath of data. */
+	ret = write(unixfd, "huge", 4);
+	assert(ret == 4);
+
+	ret = read(unixfd, &expect_len, sizeof(expect_len));
+	assert(ret == (ssize_t)sizeof(expect_len));
+
+	/* peer should send us a few mb of data */
+	if (expect_len <= sizeof(buf))
+		xerror("expect len %zu too small\n", expect_len);
+
+	tot = 0;
+	do {
+		iov.iov_len = sizeof(buf);
+		ret = recvmsg(fd, &msg, 0);
+		if (ret < 0)
+			die_perror("recvmsg");
+
+		tot += ret;
+
+		get_tcp_inq(&msg, &tcp_inq);
+
+		if (tcp_inq > expect_len - tot)
+			xerror("inq %d, remaining %d total_len %d\n",
+			       tcp_inq, expect_len - tot, (int)expect_len);
+
+		assert(tcp_inq <= expect_len - tot);
+	} while ((size_t)tot < expect_len);
+
+	ret = write(unixfd, "shut", 4);
+	assert(ret == 4);
+
+	/* wait for hangup. Should have received one more byte of data. */
+	ret = read(unixfd, tmp, sizeof(tmp));
+	assert(ret == 6);
+	assert(strncmp(tmp, "closed", 6) == 0);
+
+	sleep(1);
+
+	iov.iov_len = 1;
+	ret = recvmsg(fd, &msg, 0);
+	if (ret < 0)
+		die_perror("recvmsg");
+	assert(ret == 1);
+
+	get_tcp_inq(&msg, &tcp_inq);
+
+	/* tcp_inq should be 1 due to received fin. */
+	assert(tcp_inq == 1);
+
+	iov.iov_len = 1;
+	ret = recvmsg(fd, &msg, 0);
+	if (ret < 0)
+		die_perror("recvmsg");
+
+	/* expect EOF */
+	assert(ret == 0);
+	get_tcp_inq(&msg, &tcp_inq);
+	assert(tcp_inq == 1);
+
+	close(fd);
+}
+
+static int xaccept(int s)
+{
+	int fd = accept(s, NULL, 0);
+
+	if (fd < 0)
+		die_perror("accept");
+
+	return fd;
+}
+
+static int server(int unixfd)
+{
+	int fd = -1, r, on = 1;
+
+	switch (pf) {
+	case AF_INET:
+		fd = sock_listen_mptcp("127.0.0.1", "15432");
+		break;
+	case AF_INET6:
+		fd = sock_listen_mptcp("::1", "15432");
+		break;
+	default:
+		xerror("Unknown pf %d\n", pf);
+		break;
+	}
+
+	r = write(unixfd, "conn", 4);
+	assert(r == 4);
+
+	alarm(15);
+	r = xaccept(fd);
+
+	if (-1 == setsockopt(r, IPPROTO_TCP, TCP_INQ, &on, sizeof(on)))
+		die_perror("setsockopt");
+
+	process_one_client(r, unixfd);
+
+	return 0;
+}
+
+static int client(int unixfd)
+{
+	int fd = -1;
+
+	alarm(15);
+
+	switch (pf) {
+	case AF_INET:
+		fd = sock_connect_mptcp("127.0.0.1", "15432", proto_tx);
+		break;
+	case AF_INET6:
+		fd = sock_connect_mptcp("::1", "15432", proto_tx);
+		break;
+	default:
+		xerror("Unknown pf %d\n", pf);
+	}
+
+	connect_one_server(fd, unixfd);
+
+	return 0;
+}
+
+static void init_rng(void)
+{
+	unsigned int foo;
+
+	if (getrandom(&foo, sizeof(foo), 0) == -1) {
+		perror("getrandom");
+		exit(1);
+	}
+
+	srand(foo);
+}
+
+static pid_t xfork(void)
+{
+	pid_t p = fork();
+
+	if (p < 0)
+		die_perror("fork");
+	else if (p == 0)
+		init_rng();
+
+	return p;
+}
+
+static int rcheck(int wstatus, const char *what)
+{
+	if (WIFEXITED(wstatus)) {
+		if (WEXITSTATUS(wstatus) == 0)
+			return 0;
+		fprintf(stderr, "%s exited, status=%d\n", what, WEXITSTATUS(wstatus));
+		return WEXITSTATUS(wstatus);
+	} else if (WIFSIGNALED(wstatus)) {
+		xerror("%s killed by signal %d\n", what, WTERMSIG(wstatus));
+	} else if (WIFSTOPPED(wstatus)) {
+		xerror("%s stopped by signal %d\n", what, WSTOPSIG(wstatus));
+	}
+
+	return 111;
+}
+
+int main(int argc, char *argv[])
+{
+	int e1, e2, wstatus;
+	pid_t s, c, ret;
+	int unixfds[2];
+
+	parse_opts(argc, argv);
+
+	e1 = socketpair(AF_UNIX, SOCK_DGRAM, 0, unixfds);
+	if (e1 < 0)
+		die_perror("pipe");
+
+	s = xfork();
+	if (s == 0)
+		return server(unixfds[1]);
+
+	close(unixfds[1]);
+
+	/* wait until server bound a socket */
+	e1 = read(unixfds[0], &e1, 4);
+	assert(e1 == 4);
+
+	c = xfork();
+	if (c == 0)
+		return client(unixfds[0]);
+
+	close(unixfds[0]);
+
+	ret = waitpid(s, &wstatus, 0);
+	if (ret == -1)
+		die_perror("waitpid");
+	e1 = rcheck(wstatus, "server");
+	ret = waitpid(c, &wstatus, 0);
+	if (ret == -1)
+		die_perror("waitpid");
+	e2 = rcheck(wstatus, "client");
+
+	return e1 ? e1 : e2;
+}
diff --git a/tools/testing/selftests/net/mptcp/mptcp_join.sh b/tools/testing/selftests/net/mptcp/mptcp_join.sh
new file mode 100755
index 000000000..2107579e2
--- /dev/null
+++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh
@@ -0,0 +1,3327 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+# Double quotes to prevent globbing and word splitting is recommended in new
+# code but we accept it, especially because there were too many before having
+# address all other issues detected by shellcheck.
+#shellcheck disable=SC2086
+
+. "$(dirname "${0}")/mptcp_lib.sh"
+
+# ShellCheck incorrectly believes that most of the code here is unreachable
+# because it's invoked by variable name, see how the "tests" array is used
+#shellcheck disable=SC2317
+
+ret=0
+sin=""
+sinfail=""
+sout=""
+cin=""
+cinfail=""
+cinsent=""
+tmpfile=""
+cout=""
+capout=""
+ns1=""
+ns2=""
+ksft_skip=4
+iptables="iptables"
+ip6tables="ip6tables"
+timeout_poll=30
+timeout_test=$((timeout_poll * 2 + 1))
+capture=0
+checksum=0
+ip_mptcp=0
+check_invert=0
+validate_checksum=0
+init=0
+
+declare -A all_tests
+declare -a only_tests_ids
+declare -a only_tests_names
+declare -A failed_tests
+TEST_COUNT=0
+TEST_NAME=""
+nr_blank=40
+
+export FAILING_LINKS=""
+
+# generated using "nfbpf_compile '(ip && (ip[54] & 0xf0) == 0x30) ||
+#				  (ip6 && (ip6[74] & 0xf0) == 0x30)'"
+CBPF_MPTCP_SUBOPTION_ADD_ADDR="14,
+			       48 0 0 0,
+			       84 0 0 240,
+			       21 0 3 64,
+			       48 0 0 54,
+			       84 0 0 240,
+			       21 6 7 48,
+			       48 0 0 0,
+			       84 0 0 240,
+			       21 0 4 96,
+			       48 0 0 74,
+			       84 0 0 240,
+			       21 0 1 48,
+			       6 0 0 65535,
+			       6 0 0 0"
+
+init_partial()
+{
+	capout=$(mktemp)
+
+	local rndh
+	rndh=$(mktemp -u XXXXXX)
+
+	ns1="ns1-$rndh"
+	ns2="ns2-$rndh"
+
+	local netns
+	for netns in "$ns1" "$ns2"; do
+		ip netns add $netns || exit $ksft_skip
+		ip -net $netns link set lo up
+		ip netns exec $netns sysctl -q net.mptcp.enabled=1
+		ip netns exec $netns sysctl -q net.mptcp.pm_type=0 2>/dev/null || true
+		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
+		if [ $checksum -eq 1 ]; then
+			ip netns exec $netns sysctl -q net.mptcp.checksum_enabled=1
+		fi
+	done
+
+	check_invert=0
+	validate_checksum=$checksum
+	FAILING_LINKS=""
+
+	#  ns1         ns2
+	# ns1eth1    ns2eth1
+	# ns1eth2    ns2eth2
+	# ns1eth3    ns2eth3
+	# ns1eth4    ns2eth4
+
+	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
+		ip -net "$ns1" addr add dead:beef:$i::1/64 dev ns1eth$i nodad
+		ip -net "$ns1" link set ns1eth$i up
+
+		ip -net "$ns2" addr add 10.0.$i.2/24 dev ns2eth$i
+		ip -net "$ns2" addr add dead:beef:$i::2/64 dev ns2eth$i nodad
+		ip -net "$ns2" link set ns2eth$i up
+
+		# let $ns2 reach any $ns1 address from any interface
+		ip -net "$ns2" route add default via 10.0.$i.1 dev ns2eth$i metric 10$i
+		ip -net "$ns2" route add default via dead:beef:$i::1 dev ns2eth$i metric 10$i
+	done
+}
+
+init_shapers()
+{
+	local i
+	for i in $(seq 1 4); do
+		tc -n $ns1 qdisc add dev ns1eth$i root netem rate 20mbit delay 1
+		tc -n $ns2 qdisc add dev ns2eth$i root netem rate 20mbit delay 1
+	done
+}
+
+cleanup_partial()
+{
+	rm -f "$capout"
+
+	local netns
+	for netns in "$ns1" "$ns2"; do
+		ip netns del $netns
+		rm -f /tmp/$netns.{nstat,out}
+	done
+}
+
+check_tools()
+{
+	mptcp_lib_check_mptcp
+	mptcp_lib_check_kallsyms
+
+	if ! ip -Version &> /dev/null; then
+		echo "SKIP: Could not run test without ip tool"
+		exit $ksft_skip
+	fi
+
+	# Use the legacy version if available to support old kernel versions
+	if iptables-legacy -V &> /dev/null; then
+		iptables="iptables-legacy"
+		ip6tables="ip6tables-legacy"
+	elif ! iptables -V &> /dev/null; then
+		echo "SKIP: Could not run all tests without iptables tool"
+		exit $ksft_skip
+	elif ! ip6tables -V &> /dev/null; then
+		echo "SKIP: Could not run all tests without ip6tables tool"
+		exit $ksft_skip
+	fi
+}
+
+init() {
+	init=1
+
+	check_tools
+
+	sin=$(mktemp)
+	sout=$(mktemp)
+	cin=$(mktemp)
+	cinsent=$(mktemp)
+	cout=$(mktemp)
+
+	trap cleanup EXIT
+
+	make_file "$cin" "client" 1
+	make_file "$sin" "server" 1
+}
+
+cleanup()
+{
+	rm -f "$cin" "$cout" "$sinfail"
+	rm -f "$sin" "$sout" "$cinsent" "$cinfail"
+	rm -f "$tmpfile"
+	cleanup_partial
+}
+
+# $1: msg
+print_title()
+{
+	printf "%03u %-36s %s" "${TEST_COUNT}" "${TEST_NAME}" "${1}"
+}
+
+# [ $1: fail msg ]
+mark_as_skipped()
+{
+	local msg="${1:-"Feature not supported"}"
+
+	mptcp_lib_fail_if_expected_feature "${msg}"
+
+	print_title "[ skip ] ${msg}"
+	printf "\n"
+}
+
+# $@: condition
+continue_if()
+{
+	if ! "${@}"; then
+		mark_as_skipped
+		return 1
+	fi
+}
+
+skip_test()
+{
+	if [ "${#only_tests_ids[@]}" -eq 0 ] && [ "${#only_tests_names[@]}" -eq 0 ]; then
+		return 1
+	fi
+
+	local i
+	for i in "${only_tests_ids[@]}"; do
+		if [ "${TEST_COUNT}" -eq "${i}" ]; then
+			return 1
+		fi
+	done
+	for i in "${only_tests_names[@]}"; do
+		if [ "${TEST_NAME}" = "${i}" ]; then
+			return 1
+		fi
+	done
+
+	return 0
+}
+
+# $1: test name
+reset()
+{
+	TEST_NAME="${1}"
+
+	TEST_COUNT=$((TEST_COUNT+1))
+
+	if skip_test; then
+		return 1
+	fi
+
+	if [ "${init}" != "1" ]; then
+		init
+	else
+		cleanup_partial
+	fi
+
+	init_partial
+
+	return 0
+}
+
+# $1: test name ; $2: counter to check
+reset_check_counter()
+{
+	reset "${1}" || return 1
+
+	local counter="${2}"
+
+	if ! nstat -asz "${counter}" | grep -wq "${counter}"; then
+		mark_as_skipped "counter '${counter}' is not available"
+		return 1
+	fi
+}
+
+# $1: test name
+reset_with_cookies()
+{
+	reset "${1}" || return 1
+
+	local netns
+	for netns in "$ns1" "$ns2"; do
+		ip netns exec $netns sysctl -q net.ipv4.tcp_syncookies=2
+	done
+}
+
+# $1: test name
+reset_with_add_addr_timeout()
+{
+	local ip="${2:-4}"
+	local tables
+
+	reset "${1}" || return 1
+
+	tables="${iptables}"
+	if [ $ip -eq 6 ]; then
+		tables="${ip6tables}"
+	fi
+
+	ip netns exec $ns1 sysctl -q net.mptcp.add_addr_timeout=1
+
+	if ! ip netns exec $ns2 $tables -A OUTPUT -p tcp \
+			-m tcp --tcp-option 30 \
+			-m bpf --bytecode \
+			"$CBPF_MPTCP_SUBOPTION_ADD_ADDR" \
+			-j DROP; then
+		mark_as_skipped "unable to set the 'add addr' rule"
+		return 1
+	fi
+}
+
+# $1: test name
+reset_with_checksum()
+{
+	local ns1_enable=$1
+	local ns2_enable=$2
+
+	reset "checksum test ${1} ${2}" || return 1
+
+	ip netns exec $ns1 sysctl -q net.mptcp.checksum_enabled=$ns1_enable
+	ip netns exec $ns2 sysctl -q net.mptcp.checksum_enabled=$ns2_enable
+
+	validate_checksum=1
+}
+
+reset_with_allow_join_id0()
+{
+	local ns1_enable=$2
+	local ns2_enable=$3
+
+	reset "${1}" || return 1
+
+	ip netns exec $ns1 sysctl -q net.mptcp.allow_join_initial_addr_port=$ns1_enable
+	ip netns exec $ns2 sysctl -q net.mptcp.allow_join_initial_addr_port=$ns2_enable
+}
+
+# Modify TCP payload without corrupting the TCP packet
+#
+# This rule inverts a 8-bit word at byte offset 148 for the 2nd TCP ACK packets
+# carrying enough data.
+# Once it is done, the TCP Checksum field is updated so the packet is still
+# considered as valid at the TCP level.
+# Because the MPTCP checksum, covering the TCP options and data, has not been
+# updated, the modification will be detected and an MP_FAIL will be emitted:
+# what we want to validate here without corrupting "random" MPTCP options.
+#
+# To avoid having tc producing this pr_info() message for each TCP ACK packets
+# not carrying enough data:
+#
+#     tc action pedit offset 162 out of bounds
+#
+# Netfilter is used to mark packets with enough data.
+setup_fail_rules()
+{
+	check_invert=1
+	validate_checksum=1
+	local i="$1"
+	local ip="${2:-4}"
+	local tables
+
+	tables="${iptables}"
+	if [ $ip -eq 6 ]; then
+		tables="${ip6tables}"
+	fi
+
+	ip netns exec $ns2 $tables \
+		-t mangle \
+		-A OUTPUT \
+		-o ns2eth$i \
+		-p tcp \
+		-m length --length 150:9999 \
+		-m statistic --mode nth --packet 1 --every 99999 \
+		-j MARK --set-mark 42 || return ${ksft_skip}
+
+	tc -n $ns2 qdisc add dev ns2eth$i clsact || return ${ksft_skip}
+	tc -n $ns2 filter add dev ns2eth$i egress \
+		protocol ip prio 1000 \
+		handle 42 fw \
+		action pedit munge offset 148 u8 invert \
+		pipe csum tcp \
+		index 100 || return ${ksft_skip}
+}
+
+reset_with_fail()
+{
+	reset_check_counter "${1}" "MPTcpExtInfiniteMapTx" || return 1
+	shift
+
+	ip netns exec $ns1 sysctl -q net.mptcp.checksum_enabled=1
+	ip netns exec $ns2 sysctl -q net.mptcp.checksum_enabled=1
+
+	local rc=0
+	setup_fail_rules "${@}" || rc=$?
+
+	if [ ${rc} -eq ${ksft_skip} ]; then
+		mark_as_skipped "unable to set the 'fail' rules"
+		return 1
+	fi
+}
+
+reset_with_tcp_filter()
+{
+	reset "${1}" || return 1
+	shift
+
+	local ns="${!1}"
+	local src="${2}"
+	local target="${3}"
+
+	if ! ip netns exec "${ns}" ${iptables} \
+			-A INPUT \
+			-s "${src}" \
+			-p tcp \
+			-j "${target}"; then
+		mark_as_skipped "unable to set the filter rules"
+		return 1
+	fi
+}
+
+fail_test()
+{
+	ret=1
+	failed_tests[${TEST_COUNT}]="${TEST_NAME}"
+}
+
+get_failed_tests_ids()
+{
+	# sorted
+	local i
+	for i in "${!failed_tests[@]}"; do
+		echo "${i}"
+	done | sort -n
+}
+
+print_file_err()
+{
+	ls -l "$1" 1>&2
+	echo "Trailing bytes are: "
+	tail -c 27 "$1"
+}
+
+check_transfer()
+{
+	local in=$1
+	local out=$2
+	local what=$3
+	local bytes=$4
+	local i a b
+
+	local line
+	if [ -n "$bytes" ]; then
+		local out_size
+		# when truncating we must check the size explicitly
+		out_size=$(wc -c $out | awk '{print $1}')
+		if [ $out_size -ne $bytes ]; then
+			echo "[ FAIL ] $what output file has wrong size ($out_size, $bytes)"
+			fail_test
+			return 1
+		fi
+
+		# note: BusyBox's "cmp" command doesn't support --bytes
+		tmpfile=$(mktemp)
+		head --bytes="$bytes" "$in" > "$tmpfile"
+		mv "$tmpfile" "$in"
+		head --bytes="$bytes" "$out" > "$tmpfile"
+		mv "$tmpfile" "$out"
+		tmpfile=""
+	fi
+	cmp -l "$in" "$out" | while read -r i a b; do
+		local sum=$((0${a} + 0${b}))
+		if [ $check_invert -eq 0 ] || [ $sum -ne $((0xff)) ]; then
+			echo "[ FAIL ] $what does not match (in, out):"
+			print_file_err "$in"
+			print_file_err "$out"
+			fail_test
+
+			return 1
+		else
+			echo "$what has inverted byte at ${i}"
+		fi
+	done
+
+	return 0
+}
+
+do_ping()
+{
+	local listener_ns="$1"
+	local connector_ns="$2"
+	local connect_addr="$3"
+
+	if ! ip netns exec ${connector_ns} ping -q -c 1 $connect_addr >/dev/null; then
+		echo "$listener_ns -> $connect_addr connectivity [ FAIL ]" 1>&2
+		fail_test
+	fi
+}
+
+link_failure()
+{
+	local ns="$1"
+
+	if [ -z "$FAILING_LINKS" ]; then
+		l=$((RANDOM%4))
+		FAILING_LINKS=$((l+1))
+	fi
+
+	local l
+	for l in $FAILING_LINKS; do
+		local veth="ns1eth$l"
+		ip -net "$ns" link set "$veth" down
+	done
+}
+
+# $1: IP address
+is_v6()
+{
+	[ -z "${1##*:*}" ]
+}
+
+# $1: ns, $2: port
+wait_local_port_listen()
+{
+	local listener_ns="${1}"
+	local port="${2}"
+
+	local port_hex
+	port_hex="$(printf "%04X" "${port}")"
+
+	local i
+	for i in $(seq 10); do
+		ip netns exec "${listener_ns}" cat /proc/net/tcp* | \
+			awk "BEGIN {rc=1} {if (\$2 ~ /:${port_hex}\$/ && \$4 ~ /0A/) {rc=0; exit}} END {exit rc}" &&
+			break
+		sleep 0.1
+	done
+}
+
+# $1: ns ; $2: counter
+get_counter()
+{
+	local ns="${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}"
+}
+
+rm_addr_count()
+{
+	get_counter "${1}" "MPTcpExtRmAddr"
+}
+
+# $1: ns, $2: old rm_addr counter in $ns
+wait_rm_addr()
+{
+	local ns="${1}"
+	local old_cnt="${2}"
+	local cnt
+
+	local i
+	for i in $(seq 10); do
+		cnt=$(rm_addr_count ${ns})
+		[ "$cnt" = "${old_cnt}" ] || break
+		sleep 0.1
+	done
+}
+
+wait_mpj()
+{
+	local ns="${1}"
+	local cnt old_cnt
+
+	old_cnt=$(get_counter ${ns} "MPTcpExtMPJoinAckRx")
+
+	local i
+	for i in $(seq 10); do
+		cnt=$(get_counter ${ns} "MPTcpExtMPJoinAckRx")
+		[ "$cnt" = "${old_cnt}" ] || break
+		sleep 0.1
+	done
+}
+
+kill_wait()
+{
+	kill $1 > /dev/null 2>&1
+	wait $1 2>/dev/null
+}
+
+kill_tests_wait()
+{
+	#shellcheck disable=SC2046
+	kill -SIGUSR1 $(ip netns pids $ns2) $(ip netns pids $ns1)
+	wait
+}
+
+pm_nl_set_limits()
+{
+	local ns=$1
+	local addrs=$2
+	local subflows=$3
+
+	if [ $ip_mptcp -eq 1 ]; 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
+}
+
+pm_nl_add_endpoint()
+{
+	local ns=$1
+	local addr=$2
+	local flags _flags
+	local port _port
+	local dev _dev
+	local id _id
+	local nr=2
+
+	local p
+	for p in "${@}"
+	do
+		if [ $p = "flags" ]; then
+			eval _flags=\$"$nr"
+			[ -n "$_flags" ]; flags="flags $_flags"
+		fi
+		if [ $p = "dev" ]; then
+			eval _dev=\$"$nr"
+			[ -n "$_dev" ]; dev="dev $_dev"
+		fi
+		if [ $p = "id" ]; then
+			eval _id=\$"$nr"
+			[ -n "$_id" ]; id="id $_id"
+		fi
+		if [ $p = "port" ]; then
+			eval _port=\$"$nr"
+			[ -n "$_port" ]; port="port $_port"
+		fi
+
+		nr=$((nr + 1))
+	done
+
+	if [ $ip_mptcp -eq 1 ]; then
+		ip -n $ns mptcp endpoint add $addr ${_flags//","/" "} $dev $id $port
+	else
+		ip netns exec $ns ./pm_nl_ctl add $addr $flags $dev $id $port
+	fi
+}
+
+pm_nl_del_endpoint()
+{
+	local ns=$1
+	local id=$2
+	local addr=$3
+
+	if [ $ip_mptcp -eq 1 ]; then
+		[ $id -ne 0 ] && addr=''
+		ip -n $ns mptcp endpoint delete id $id $addr
+	else
+		ip netns exec $ns ./pm_nl_ctl del $id $addr
+	fi
+}
+
+pm_nl_flush_endpoint()
+{
+	local ns=$1
+
+	if [ $ip_mptcp -eq 1 ]; then
+		ip -n $ns mptcp endpoint flush
+	else
+		ip netns exec $ns ./pm_nl_ctl flush
+	fi
+}
+
+pm_nl_show_endpoints()
+{
+	local ns=$1
+
+	if [ $ip_mptcp -eq 1 ]; then
+		ip -n $ns mptcp endpoint show
+	else
+		ip netns exec $ns ./pm_nl_ctl dump
+	fi
+}
+
+pm_nl_change_endpoint()
+{
+	local ns=$1
+	local id=$2
+	local flags=$3
+
+	if [ $ip_mptcp -eq 1 ]; then
+		ip -n $ns mptcp endpoint change id $id ${flags//","/" "}
+	else
+		ip netns exec $ns ./pm_nl_ctl set id $id flags $flags
+	fi
+}
+
+pm_nl_check_endpoint()
+{
+	local line expected_line
+	local need_title=$1
+	local msg="$2"
+	local ns=$3
+	local addr=$4
+	local _flags=""
+	local flags
+	local _port
+	local port
+	local dev
+	local _id
+	local id
+
+	if [ "${need_title}" = 1 ]; then
+		printf "%03u %-36s %s" "${TEST_COUNT}" "${TEST_NAME}" "${msg}"
+	else
+		printf "%-${nr_blank}s %s" " " "${msg}"
+	fi
+
+	shift 4
+	while [ -n "$1" ]; do
+		if [ $1 = "flags" ]; then
+			_flags=$2
+			[ -n "$_flags" ]; flags="flags $_flags"
+			shift
+		elif [ $1 = "dev" ]; then
+			[ -n "$2" ]; dev="dev $1"
+			shift
+		elif [ $1 = "id" ]; then
+			_id=$2
+			[ -n "$_id" ]; id="id $_id"
+			shift
+		elif [ $1 = "port" ]; then
+			_port=$2
+			[ -n "$_port" ]; port=" port $_port"
+			shift
+		fi
+
+		shift
+	done
+
+	if [ -z "$id" ]; then
+		echo "[skip] bad test - missing endpoint id"
+		return
+	fi
+
+	if [ $ip_mptcp -eq 1 ]; then
+		# get line and trim trailing whitespace
+		line=$(ip -n $ns mptcp endpoint show $id)
+		line="${line% }"
+		# the dump order is: address id flags port dev
+		[ -n "$addr" ] && expected_line="$addr"
+		expected_line="$expected_line $id"
+		[ -n "$_flags" ] && expected_line="$expected_line ${_flags//","/" "}"
+		[ -n "$dev" ] && expected_line="$expected_line $dev"
+		[ -n "$port" ] && expected_line="$expected_line $port"
+	else
+		line=$(ip netns exec $ns ./pm_nl_ctl get $_id)
+		# the dump order is: id flags dev address port
+		expected_line="$id"
+		[ -n "$flags" ] && expected_line="$expected_line $flags"
+		[ -n "$dev" ] && expected_line="$expected_line $dev"
+		[ -n "$addr" ] && expected_line="$expected_line $addr"
+		[ -n "$_port" ] && expected_line="$expected_line $_port"
+	fi
+	if [ "$line" = "$expected_line" ]; then
+		echo "[ ok ]"
+	else
+		echo "[fail] expected '$expected_line' found '$line'"
+		fail_test
+	fi
+}
+
+do_transfer()
+{
+	local listener_ns="$1"
+	local connector_ns="$2"
+	local cl_proto="$3"
+	local srv_proto="$4"
+	local connect_addr="$5"
+	local test_link_fail="$6"
+	local addr_nr_ns1="$7"
+	local addr_nr_ns2="$8"
+	local speed="$9"
+	local sflags="${10}"
+
+	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"
+	:> "$sout"
+	:> "$capout"
+
+	if [ $capture -eq 1 ]; then
+		local capuser
+		if [ -z $SUDO_USER ] ; then
+			capuser=""
+		else
+			capuser="-Z $SUDO_USER"
+		fi
+
+		capfile=$(printf "mp_join-%02u-%s.pcap" "$TEST_COUNT" "${listener_ns}")
+
+		echo "Capturing traffic for test $TEST_COUNT into $capfile"
+		ip netns exec ${listener_ns} tcpdump -i any -s 65535 -B 32768 $capuser -w $capfile > "$capout" 2>&1 &
+		cappid=$!
+
+		sleep 1
+	fi
+
+	NSTAT_HISTORY=/tmp/${listener_ns}.nstat ip netns exec ${listener_ns} \
+		nstat -n
+	NSTAT_HISTORY=/tmp/${connector_ns}.nstat ip netns exec ${connector_ns} \
+		nstat -n
+
+	local extra_args
+	if [ $speed = "fast" ]; then
+		extra_args="-j"
+	elif [ $speed = "slow" ]; then
+		extra_args="-r 50"
+	elif [[ $speed = "speed_"* ]]; then
+		extra_args="-r ${speed:6}"
+	fi
+
+	if [[ "${addr_nr_ns1}" = "userspace_"* ]]; then
+		userspace_pm=1
+		addr_nr_ns1=${addr_nr_ns1:10}
+	fi
+
+	local flags="subflow"
+	local extra_cl_args=""
+	local extra_srv_args=""
+	local trunc_size=""
+	if [[ "${addr_nr_ns2}" = "fastclose_"* ]]; then
+		if [ ${test_link_fail} -le 1 ]; then
+			echo "fastclose tests need test_link_fail argument"
+			fail_test
+			return 1
+		fi
+
+		# disconnect
+		trunc_size=${test_link_fail}
+		local side=${addr_nr_ns2:10}
+
+		if [ ${side} = "client" ]; then
+			extra_cl_args="-f ${test_link_fail}"
+			extra_srv_args="-f -1"
+		elif [ ${side} = "server" ]; then
+			extra_srv_args="-f ${test_link_fail}"
+			extra_cl_args="-f -1"
+		else
+			echo "wrong/unknown fastclose spec ${side}"
+			fail_test
+			return 1
+		fi
+		addr_nr_ns2=0
+	elif [[ "${addr_nr_ns2}" = "userspace_"* ]]; then
+		userspace_pm=1
+		addr_nr_ns2=${addr_nr_ns2:10}
+	elif [[ "${addr_nr_ns2}" = "fullmesh_"* ]]; then
+		flags="${flags},fullmesh"
+		addr_nr_ns2=${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="::"
+	else
+		local_addr="0.0.0.0"
+	fi
+
+	extra_srv_args="$extra_args $extra_srv_args"
+	if [ "$test_link_fail" -gt 1 ];then
+		timeout ${timeout_test} \
+			ip netns exec ${listener_ns} \
+				./mptcp_connect -t ${timeout_poll} -l -p $port -s ${srv_proto} \
+					$extra_srv_args ${local_addr} < "$sinfail" > "$sout" &
+	else
+		timeout ${timeout_test} \
+			ip netns exec ${listener_ns} \
+				./mptcp_connect -t ${timeout_poll} -l -p $port -s ${srv_proto} \
+					$extra_srv_args ${local_addr} < "$sin" > "$sout" &
+	fi
+	local spid=$!
+
+	wait_local_port_listen "${listener_ns}" "${port}"
+
+	extra_cl_args="$extra_args $extra_cl_args"
+	if [ "$test_link_fail" -eq 0 ];then
+		timeout ${timeout_test} \
+			ip netns exec ${connector_ns} \
+				./mptcp_connect -t ${timeout_poll} -p $port -s ${cl_proto} \
+					$extra_cl_args $connect_addr < "$cin" > "$cout" &
+	elif [ "$test_link_fail" -eq 1 ] || [ "$test_link_fail" -eq 2 ];then
+		( cat "$cinfail" ; sleep 2; link_failure $listener_ns ; cat "$cinfail" ) | \
+			tee "$cinsent" | \
+			timeout ${timeout_test} \
+				ip netns exec ${connector_ns} \
+					./mptcp_connect -t ${timeout_poll} -p $port -s ${cl_proto} \
+						$extra_cl_args $connect_addr > "$cout" &
+	else
+		tee "$cinsent" < "$cinfail" | \
+			timeout ${timeout_test} \
+				ip netns exec ${connector_ns} \
+					./mptcp_connect -t ${timeout_poll} -p $port -s ${cl_proto} \
+						$extra_cl_args $connect_addr > "$cout" &
+	fi
+	local cpid=$!
+
+	# let the mptcp subflow be established in background before
+	# do endpoint manipulation
+	if [ $addr_nr_ns1 != "0" ] || [ $addr_nr_ns2 != "0" ]; then
+		sleep 1
+	fi
+
+	if [ $addr_nr_ns1 -gt 0 ]; then
+		local counter=2
+		local add_nr_ns1=${addr_nr_ns1}
+		local id=10
+		local tk
+		while [ $add_nr_ns1 -gt 0 ]; do
+			local addr
+			if is_v6 "${connect_addr}"; then
+				addr="dead:beef:$counter::1"
+			else
+				addr="10.0.$counter.1"
+			fi
+			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")
+				ip netns exec ${listener_ns} ./pm_nl_ctl ann $addr token $tk id $id
+				sleep 1
+				sp=$(grep "type:10" "$evts_ns1" |
+				     sed -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q')
+				da=$(grep "type:10" "$evts_ns1" |
+				     sed -n 's/.*\(daddr[46]:\)\([0-9a-f:.]*\).*$/\2/p;q')
+				echo "$da" | grep -q ":" && addr="::ffff:$addr"
+				dp=$(grep "type:10" "$evts_ns1" |
+				     sed -n 's/.*\(dport:\)\([[:digit:]]*\).*$/\2/p;q')
+				ip netns exec ${listener_ns} ./pm_nl_ctl rem token $tk id $id
+				ip netns exec ${listener_ns} ./pm_nl_ctl dsf lip "$addr" \
+							lport $sp rip $da rport $dp token $tk
+			fi
+
+			counter=$((counter + 1))
+			add_nr_ns1=$((add_nr_ns1 - 1))
+			id=$((id + 1))
+		done
+	elif [ $addr_nr_ns1 -lt 0 ]; then
+		local rm_nr_ns1=$((-addr_nr_ns1))
+		if [ $rm_nr_ns1 -lt 8 ]; then
+			local counter=0
+			local line
+			pm_nl_show_endpoints ${listener_ns} | while read -r line; do
+				# shellcheck disable=SC2206 # we do want to split per word
+				local arr=($line)
+				local nr=0
+
+				local i
+				for i in "${arr[@]}"; do
+					if [ $i = "id" ]; then
+						if [ $counter -eq $rm_nr_ns1 ]; then
+							break
+						fi
+						id=${arr[$nr+1]}
+						rm_addr=$(rm_addr_count ${connector_ns})
+						pm_nl_del_endpoint ${listener_ns} $id
+						wait_rm_addr ${connector_ns} ${rm_addr}
+						counter=$((counter + 1))
+					fi
+					nr=$((nr + 1))
+				done
+			done
+		elif [ $rm_nr_ns1 -eq 8 ]; then
+			pm_nl_flush_endpoint ${listener_ns}
+		elif [ $rm_nr_ns1 -eq 9 ]; then
+			pm_nl_del_endpoint ${listener_ns} 0 ${connect_addr}
+		fi
+	fi
+
+	# if newly added endpoints must be deleted, give the background msk
+	# some time to created them
+	[ $addr_nr_ns1 -gt 0 ] && [ $addr_nr_ns2 -lt 0 ] && sleep 1
+
+	if [ $addr_nr_ns2 -gt 0 ]; then
+		local add_nr_ns2=${addr_nr_ns2}
+		local counter=3
+		local id=20
+		local tk da dp sp
+		while [ $add_nr_ns2 -gt 0 ]; do
+			local addr
+			if is_v6 "${connect_addr}"; then
+				addr="dead:beef:$counter::2"
+			else
+				addr="10.0.$counter.2"
+			fi
+			if [ $userspace_pm -eq 0 ]; then
+				pm_nl_add_endpoint $ns2 $addr flags $flags
+			else
+				tk=$(sed -n 's/.*\(token:\)\([[:digit:]]*\).*$/\2/p;q' "$evts_ns2")
+				da=$(sed -n 's/.*\(daddr4:\)\([0-9.]*\).*$/\2/p;q' "$evts_ns2")
+				dp=$(sed -n 's/.*\(dport:\)\([[:digit:]]*\).*$/\2/p;q' "$evts_ns2")
+				ip netns exec ${connector_ns} ./pm_nl_ctl csf lip $addr lid $id \
+									rip $da rport $dp token $tk
+				sleep 1
+				sp=$(grep "type:10" "$evts_ns2" |
+				     sed -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q')
+				ip netns exec ${connector_ns} ./pm_nl_ctl rem token $tk id $id
+				ip netns exec ${connector_ns} ./pm_nl_ctl dsf lip $addr lport $sp \
+									rip $da rport $dp token $tk
+			fi
+			counter=$((counter + 1))
+			add_nr_ns2=$((add_nr_ns2 - 1))
+			id=$((id + 1))
+		done
+	elif [ $addr_nr_ns2 -lt 0 ]; then
+		local rm_nr_ns2=$((-addr_nr_ns2))
+		if [ $rm_nr_ns2 -lt 8 ]; then
+			local counter=0
+			local line
+			pm_nl_show_endpoints ${connector_ns} | while read -r line; do
+				# shellcheck disable=SC2206 # we do want to split per word
+				local arr=($line)
+				local nr=0
+
+				local i
+				for i in "${arr[@]}"; do
+					if [ $i = "id" ]; then
+						if [ $counter -eq $rm_nr_ns2 ]; then
+							break
+						fi
+						local id rm_addr
+						# rm_addr are serialized, allow the previous one to
+						# complete
+						id=${arr[$nr+1]}
+						rm_addr=$(rm_addr_count ${listener_ns})
+						pm_nl_del_endpoint ${connector_ns} $id
+						wait_rm_addr ${listener_ns} ${rm_addr}
+						counter=$((counter + 1))
+					fi
+					nr=$((nr + 1))
+				done
+			done
+		elif [ $rm_nr_ns2 -eq 8 ]; then
+			pm_nl_flush_endpoint ${connector_ns}
+		elif [ $rm_nr_ns2 -eq 9 ]; then
+			local addr
+			if is_v6 "${connect_addr}"; then
+				addr="dead:beef:1::2"
+			else
+				addr="10.0.1.2"
+			fi
+			pm_nl_del_endpoint ${connector_ns} 0 $addr
+		fi
+	fi
+
+	if [ -n "${sflags}" ]; then
+		sleep 1
+
+		local netns
+		for netns in "$ns1" "$ns2"; do
+			local line
+			pm_nl_show_endpoints $netns | while read -r line; do
+				# shellcheck disable=SC2206 # we do want to split per word
+				local arr=($line)
+				local nr=0
+				local id
+
+				local i
+				for i in "${arr[@]}"; do
+					if [ $i = "id" ]; then
+						id=${arr[$nr+1]}
+					fi
+					nr=$((nr + 1))
+				done
+				pm_nl_change_endpoint $netns $id $sflags
+			done
+		done
+	fi
+
+	wait $cpid
+	local retc=$?
+	wait $spid
+	local rets=$?
+
+	if [ $capture -eq 1 ]; then
+	    sleep 1
+	    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 ${connector_ns} \
+		nstat | grep Tcp > /tmp/${connector_ns}.out
+
+	if [ ${rets} -ne 0 ] || [ ${retc} -ne 0 ]; then
+		echo " client exit code $retc, server $rets" 1>&2
+		echo -e "\nnetns ${listener_ns} socket stat for ${port}:" 1>&2
+		ip netns exec ${listener_ns} ss -Menita 1>&2 -o "sport = :$port"
+		cat /tmp/${listener_ns}.out
+		echo -e "\nnetns ${connector_ns} socket stat for ${port}:" 1>&2
+		ip netns exec ${connector_ns} ss -Menita 1>&2 -o "dport = :$port"
+		cat /tmp/${connector_ns}.out
+
+		cat "$capout"
+		fail_test
+		return 1
+	fi
+
+	if [ "$test_link_fail" -gt 1 ];then
+		check_transfer $sinfail $cout "file received by client" $trunc_size
+	else
+		check_transfer $sin $cout "file received by client" $trunc_size
+	fi
+	retc=$?
+	if [ "$test_link_fail" -eq 0 ];then
+		check_transfer $cin $sout "file received by server" $trunc_size
+	else
+		check_transfer $cinsent $sout "file received by server" $trunc_size
+	fi
+	rets=$?
+
+	if [ $retc -eq 0 ] && [ $rets -eq 0 ];then
+		cat "$capout"
+		return 0
+	fi
+
+	cat "$capout"
+	return 1
+}
+
+make_file()
+{
+	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"
+
+	echo "Created $name (size $size KB) containing data sent by $who"
+}
+
+run_tests()
+{
+	local listener_ns="$1"
+	local connector_ns="$2"
+	local connect_addr="$3"
+	local test_linkfail="${4:-0}"
+	local addr_nr_ns1="${5:-0}"
+	local addr_nr_ns2="${6:-0}"
+	local speed="${7:-fast}"
+	local sflags="${8:-""}"
+
+	local size
+
+	# The values above 2 are reused to make test files
+	# with the given sizes (KB)
+	if [ "$test_linkfail" -gt 2 ]; then
+		size=$test_linkfail
+
+		if [ -z "$cinfail" ]; then
+			cinfail=$(mktemp)
+		fi
+		make_file "$cinfail" "client" $size
+	# create the input file for the failure test when
+	# the first failure test run
+	elif [ "$test_linkfail" -ne 0 ] && [ -z "$cinfail" ]; then
+		# the client file must be considerably larger
+		# of the maximum expected cwin value, or the
+		# link utilization will be not predicable
+		size=$((RANDOM%2))
+		size=$((size+1))
+		size=$((size*8192))
+		size=$((size + ( RANDOM % 8192) ))
+
+		cinfail=$(mktemp)
+		make_file "$cinfail" "client" $size
+	fi
+
+	if [ "$test_linkfail" -gt 2 ]; then
+		size=$test_linkfail
+
+		if [ -z "$sinfail" ]; then
+			sinfail=$(mktemp)
+		fi
+		make_file "$sinfail" "server" $size
+	elif [ "$test_linkfail" -eq 2 ] && [ -z "$sinfail" ]; then
+		size=$((RANDOM%16))
+		size=$((size+1))
+		size=$((size*2048))
+
+		sinfail=$(mktemp)
+		make_file "$sinfail" "server" $size
+	fi
+
+	do_transfer ${listener_ns} ${connector_ns} MPTCP MPTCP ${connect_addr} \
+		${test_linkfail} ${addr_nr_ns1} ${addr_nr_ns2} ${speed} ${sflags}
+}
+
+dump_stats()
+{
+	echo Server ns stats
+	ip netns exec $ns1 nstat -as | grep Tcp
+	echo Client ns stats
+	ip netns exec $ns2 nstat -as | grep Tcp
+}
+
+chk_csum_nr()
+{
+	local csum_ns1=${1:-0}
+	local csum_ns2=${2:-0}
+	local count
+	local dump_stats
+	local extra_msg=""
+	local allow_multi_errors_ns1=0
+	local allow_multi_errors_ns2=0
+
+	if [[ "${csum_ns1}" = "+"* ]]; then
+		allow_multi_errors_ns1=1
+		csum_ns1=${csum_ns1:1}
+	fi
+	if [[ "${csum_ns2}" = "+"* ]]; then
+		allow_multi_errors_ns2=1
+		csum_ns2=${csum_ns2:1}
+	fi
+
+	printf "%-${nr_blank}s %s" " " "sum"
+	count=$(get_counter ${ns1} "MPTcpExtDataCsumErr")
+	if [ "$count" != "$csum_ns1" ]; then
+		extra_msg="$extra_msg ns1=$count"
+	fi
+	if [ -z "$count" ]; then
+		echo -n "[skip]"
+	elif { [ "$count" != $csum_ns1 ] && [ $allow_multi_errors_ns1 -eq 0 ]; } ||
+	   { [ "$count" -lt $csum_ns1 ] && [ $allow_multi_errors_ns1 -eq 1 ]; }; then
+		echo "[fail] got $count data checksum error[s] expected $csum_ns1"
+		fail_test
+		dump_stats=1
+	else
+		echo -n "[ ok ]"
+	fi
+	echo -n " - csum  "
+	count=$(get_counter ${ns2} "MPTcpExtDataCsumErr")
+	if [ "$count" != "$csum_ns2" ]; then
+		extra_msg="$extra_msg ns2=$count"
+	fi
+	if [ -z "$count" ]; then
+		echo -n "[skip]"
+	elif { [ "$count" != $csum_ns2 ] && [ $allow_multi_errors_ns2 -eq 0 ]; } ||
+	   { [ "$count" -lt $csum_ns2 ] && [ $allow_multi_errors_ns2 -eq 1 ]; }; then
+		echo "[fail] got $count data checksum error[s] expected $csum_ns2"
+		fail_test
+		dump_stats=1
+	else
+		echo -n "[ ok ]"
+	fi
+	[ "${dump_stats}" = 1 ] && dump_stats
+
+	echo "$extra_msg"
+}
+
+chk_fail_nr()
+{
+	local fail_tx=$1
+	local fail_rx=$2
+	local ns_invert=${3:-""}
+	local count
+	local dump_stats
+	local ns_tx=$ns1
+	local ns_rx=$ns2
+	local extra_msg=""
+	local allow_tx_lost=0
+	local allow_rx_lost=0
+
+	if [[ $ns_invert = "invert" ]]; then
+		ns_tx=$ns2
+		ns_rx=$ns1
+		extra_msg=" invert"
+	fi
+
+	if [[ "${fail_tx}" = "-"* ]]; then
+		allow_tx_lost=1
+		fail_tx=${fail_tx:1}
+	fi
+	if [[ "${fail_rx}" = "-"* ]]; then
+		allow_rx_lost=1
+		fail_rx=${fail_rx:1}
+	fi
+
+	printf "%-${nr_blank}s %s" " " "ftx"
+	count=$(get_counter ${ns_tx} "MPTcpExtMPFailTx")
+	if [ "$count" != "$fail_tx" ]; then
+		extra_msg="$extra_msg,tx=$count"
+	fi
+	if [ -z "$count" ]; then
+		echo -n "[skip]"
+	elif { [ "$count" != "$fail_tx" ] && [ $allow_tx_lost -eq 0 ]; } ||
+	   { [ "$count" -gt "$fail_tx" ] && [ $allow_tx_lost -eq 1 ]; }; then
+		echo "[fail] got $count MP_FAIL[s] TX expected $fail_tx"
+		fail_test
+		dump_stats=1
+	else
+		echo -n "[ ok ]"
+	fi
+
+	echo -n " - failrx"
+	count=$(get_counter ${ns_rx} "MPTcpExtMPFailRx")
+	if [ "$count" != "$fail_rx" ]; then
+		extra_msg="$extra_msg,rx=$count"
+	fi
+	if [ -z "$count" ]; then
+		echo -n "[skip]"
+	elif { [ "$count" != "$fail_rx" ] && [ $allow_rx_lost -eq 0 ]; } ||
+	   { [ "$count" -gt "$fail_rx" ] && [ $allow_rx_lost -eq 1 ]; }; then
+		echo "[fail] got $count MP_FAIL[s] RX expected $fail_rx"
+		fail_test
+		dump_stats=1
+	else
+		echo -n "[ ok ]"
+	fi
+
+	[ "${dump_stats}" = 1 ] && dump_stats
+
+	echo "$extra_msg"
+}
+
+chk_fclose_nr()
+{
+	local fclose_tx=$1
+	local fclose_rx=$2
+	local ns_invert=$3
+	local count
+	local dump_stats
+	local ns_tx=$ns2
+	local ns_rx=$ns1
+	local extra_msg="   "
+
+	if [[ $ns_invert = "invert" ]]; then
+		ns_tx=$ns1
+		ns_rx=$ns2
+		extra_msg=${extra_msg}"invert"
+	fi
+
+	printf "%-${nr_blank}s %s" " " "ctx"
+	count=$(get_counter ${ns_tx} "MPTcpExtMPFastcloseTx")
+	if [ -z "$count" ]; then
+		echo -n "[skip]"
+	elif [ "$count" != "$fclose_tx" ]; then
+		extra_msg="$extra_msg,tx=$count"
+		echo "[fail] got $count MP_FASTCLOSE[s] TX expected $fclose_tx"
+		fail_test
+		dump_stats=1
+	else
+		echo -n "[ ok ]"
+	fi
+
+	echo -n " - fclzrx"
+	count=$(get_counter ${ns_rx} "MPTcpExtMPFastcloseRx")
+	if [ -z "$count" ]; then
+		echo -n "[skip]"
+	elif [ "$count" != "$fclose_rx" ]; then
+		extra_msg="$extra_msg,rx=$count"
+		echo "[fail] got $count MP_FASTCLOSE[s] RX expected $fclose_rx"
+		fail_test
+		dump_stats=1
+	else
+		echo -n "[ ok ]"
+	fi
+
+	[ "${dump_stats}" = 1 ] && dump_stats
+
+	echo "$extra_msg"
+}
+
+chk_rst_nr()
+{
+	local rst_tx=$1
+	local rst_rx=$2
+	local ns_invert=${3:-""}
+	local count
+	local dump_stats
+	local ns_tx=$ns1
+	local ns_rx=$ns2
+	local extra_msg=""
+
+	if [[ $ns_invert = "invert" ]]; then
+		ns_tx=$ns2
+		ns_rx=$ns1
+		extra_msg="   invert"
+	fi
+
+	printf "%-${nr_blank}s %s" " " "rtx"
+	count=$(get_counter ${ns_tx} "MPTcpExtMPRstTx")
+	if [ -z "$count" ]; then
+		echo -n "[skip]"
+	# accept more rst than expected except if we don't expect any
+	elif { [ $rst_tx -ne 0 ] && [ $count -lt $rst_tx ]; } ||
+	     { [ $rst_tx -eq 0 ] && [ $count -ne 0 ]; }; then
+		echo "[fail] got $count MP_RST[s] TX expected $rst_tx"
+		fail_test
+		dump_stats=1
+	else
+		echo -n "[ ok ]"
+	fi
+
+	echo -n " - rstrx "
+	count=$(get_counter ${ns_rx} "MPTcpExtMPRstRx")
+	if [ -z "$count" ]; then
+		echo -n "[skip]"
+	# accept more rst than expected except if we don't expect any
+	elif { [ $rst_rx -ne 0 ] && [ $count -lt $rst_rx ]; } ||
+	     { [ $rst_rx -eq 0 ] && [ $count -ne 0 ]; }; then
+		echo "[fail] got $count MP_RST[s] RX expected $rst_rx"
+		fail_test
+		dump_stats=1
+	else
+		echo -n "[ ok ]"
+	fi
+
+	[ "${dump_stats}" = 1 ] && dump_stats
+
+	echo "$extra_msg"
+}
+
+chk_infi_nr()
+{
+	local infi_tx=$1
+	local infi_rx=$2
+	local count
+	local dump_stats
+
+	printf "%-${nr_blank}s %s" " " "itx"
+	count=$(get_counter ${ns2} "MPTcpExtInfiniteMapTx")
+	if [ -z "$count" ]; then
+		echo -n "[skip]"
+	elif [ "$count" != "$infi_tx" ]; then
+		echo "[fail] got $count infinite map[s] TX expected $infi_tx"
+		fail_test
+		dump_stats=1
+	else
+		echo -n "[ ok ]"
+	fi
+
+	echo -n " - infirx"
+	count=$(get_counter ${ns1} "MPTcpExtInfiniteMapRx")
+	if [ -z "$count" ]; then
+		echo "[skip]"
+	elif [ "$count" != "$infi_rx" ]; then
+		echo "[fail] got $count infinite map[s] RX expected $infi_rx"
+		fail_test
+		dump_stats=1
+	else
+		echo "[ ok ]"
+	fi
+
+	[ "${dump_stats}" = 1 ] && dump_stats
+}
+
+chk_join_nr()
+{
+	local syn_nr=$1
+	local syn_ack_nr=$2
+	local ack_nr=$3
+	local csum_ns1=${4:-0}
+	local csum_ns2=${5:-0}
+	local fail_nr=${6:-0}
+	local rst_nr=${7:-0}
+	local infi_nr=${8:-0}
+	local corrupted_pkts=${9:-0}
+	local count
+	local dump_stats
+	local with_cookie
+	local title="${TEST_NAME}"
+
+	if [ "${corrupted_pkts}" -gt 0 ]; then
+		title+=": ${corrupted_pkts} corrupted pkts"
+	fi
+
+	printf "%03u %-36s %s" "${TEST_COUNT}" "${title}" "syn"
+	count=$(get_counter ${ns1} "MPTcpExtMPJoinSynRx")
+	if [ -z "$count" ]; then
+		echo -n "[skip]"
+	elif [ "$count" != "$syn_nr" ]; then
+		echo "[fail] got $count JOIN[s] syn expected $syn_nr"
+		fail_test
+		dump_stats=1
+	else
+		echo -n "[ ok ]"
+	fi
+
+	echo -n " - synack"
+	with_cookie=$(ip netns exec $ns2 sysctl -n net.ipv4.tcp_syncookies)
+	count=$(get_counter ${ns2} "MPTcpExtMPJoinSynAckRx")
+	if [ -z "$count" ]; then
+		echo -n "[skip]"
+	elif [ "$count" != "$syn_ack_nr" ]; then
+		# simult connections exceeding the limit with cookie enabled could go up to
+		# synack validation as the conn limit can be enforced reliably only after
+		# the subflow creation
+		if [ "$with_cookie" = 2 ] && [ "$count" -gt "$syn_ack_nr" ] && [ "$count" -le "$syn_nr" ]; then
+			echo -n "[ ok ]"
+		else
+			echo "[fail] got $count JOIN[s] synack expected $syn_ack_nr"
+			fail_test
+			dump_stats=1
+		fi
+	else
+		echo -n "[ ok ]"
+	fi
+
+	echo -n " - ack"
+	count=$(get_counter ${ns1} "MPTcpExtMPJoinAckRx")
+	if [ -z "$count" ]; then
+		echo "[skip]"
+	elif [ "$count" != "$ack_nr" ]; then
+		echo "[fail] got $count JOIN[s] ack expected $ack_nr"
+		fail_test
+		dump_stats=1
+	else
+		echo "[ ok ]"
+	fi
+	[ "${dump_stats}" = 1 ] && dump_stats
+	if [ $validate_checksum -eq 1 ]; then
+		chk_csum_nr $csum_ns1 $csum_ns2
+		chk_fail_nr $fail_nr $fail_nr
+		chk_rst_nr $rst_nr $rst_nr
+		chk_infi_nr $infi_nr $infi_nr
+	fi
+}
+
+# a negative value for 'stale_max' means no upper bound:
+# for bidirectional transfer, if one peer sleep for a while
+# - as these tests do - we can have a quite high number of
+# stale/recover conversions, proportional to
+# sleep duration/ MPTCP-level RTX interval.
+chk_stale_nr()
+{
+	local ns=$1
+	local stale_min=$2
+	local stale_max=$3
+	local stale_delta=$4
+	local dump_stats
+	local stale_nr
+	local recover_nr
+
+	printf "%-${nr_blank}s %-18s" " " "stale"
+
+	stale_nr=$(get_counter ${ns} "MPTcpExtSubflowStale")
+	recover_nr=$(get_counter ${ns} "MPTcpExtSubflowRecover")
+	if [ -z "$stale_nr" ] || [ -z "$recover_nr" ]; then
+		echo "[skip]"
+	elif [ $stale_nr -lt $stale_min ] ||
+	   { [ $stale_max -gt 0 ] && [ $stale_nr -gt $stale_max ]; } ||
+	   [ $((stale_nr - recover_nr)) -ne $stale_delta ]; then
+		echo "[fail] got $stale_nr stale[s] $recover_nr recover[s], " \
+		     " expected stale in range [$stale_min..$stale_max]," \
+		     " stale-recover delta $stale_delta "
+		fail_test
+		dump_stats=1
+	else
+		echo "[ ok ]"
+	fi
+
+	if [ "${dump_stats}" = 1 ]; then
+		echo $ns stats
+		ip netns exec $ns ip -s link show
+		ip netns exec $ns nstat -as | grep MPTcp
+	fi
+}
+
+chk_add_nr()
+{
+	local add_nr=$1
+	local echo_nr=$2
+	local port_nr=${3:-0}
+	local syn_nr=${4:-$port_nr}
+	local syn_ack_nr=${5:-$port_nr}
+	local ack_nr=${6:-$port_nr}
+	local mis_syn_nr=${7:-0}
+	local mis_ack_nr=${8:-0}
+	local count
+	local dump_stats
+	local timeout
+
+	timeout=$(ip netns exec $ns1 sysctl -n net.mptcp.add_addr_timeout)
+
+	printf "%-${nr_blank}s %s" " " "add"
+	count=$(get_counter ${ns2} "MPTcpExtAddAddr")
+	if [ -z "$count" ]; then
+		echo -n "[skip]"
+	# if the test configured a short timeout tolerate greater then expected
+	# add addrs options, due to retransmissions
+	elif [ "$count" != "$add_nr" ] && { [ "$timeout" -gt 1 ] || [ "$count" -lt "$add_nr" ]; }; then
+		echo "[fail] got $count ADD_ADDR[s] expected $add_nr"
+		fail_test
+		dump_stats=1
+	else
+		echo -n "[ ok ]"
+	fi
+
+	echo -n " - echo  "
+	count=$(get_counter ${ns1} "MPTcpExtEchoAdd")
+	if [ -z "$count" ]; then
+		echo -n "[skip]"
+	elif [ "$count" != "$echo_nr" ]; then
+		echo "[fail] got $count ADD_ADDR echo[s] expected $echo_nr"
+		fail_test
+		dump_stats=1
+	else
+		echo -n "[ ok ]"
+	fi
+
+	if [ $port_nr -gt 0 ]; then
+		echo -n " - pt "
+		count=$(get_counter ${ns2} "MPTcpExtPortAdd")
+		if [ -z "$count" ]; then
+			echo "[skip]"
+		elif [ "$count" != "$port_nr" ]; then
+			echo "[fail] got $count ADD_ADDR[s] with a port-number expected $port_nr"
+			fail_test
+			dump_stats=1
+		else
+			echo "[ ok ]"
+		fi
+
+		printf "%-${nr_blank}s %s" " " "syn"
+		count=$(get_counter ${ns1} "MPTcpExtMPJoinPortSynRx")
+		if [ -z "$count" ]; then
+			echo -n "[skip]"
+		elif [ "$count" != "$syn_nr" ]; then
+			echo "[fail] got $count JOIN[s] syn with a different \
+				port-number expected $syn_nr"
+			fail_test
+			dump_stats=1
+		else
+			echo -n "[ ok ]"
+		fi
+
+		echo -n " - synack"
+		count=$(get_counter ${ns2} "MPTcpExtMPJoinPortSynAckRx")
+		if [ -z "$count" ]; then
+			echo -n "[skip]"
+		elif [ "$count" != "$syn_ack_nr" ]; then
+			echo "[fail] got $count JOIN[s] synack with a different \
+				port-number expected $syn_ack_nr"
+			fail_test
+			dump_stats=1
+		else
+			echo -n "[ ok ]"
+		fi
+
+		echo -n " - ack"
+		count=$(get_counter ${ns1} "MPTcpExtMPJoinPortAckRx")
+		if [ -z "$count" ]; then
+			echo "[skip]"
+		elif [ "$count" != "$ack_nr" ]; then
+			echo "[fail] got $count JOIN[s] ack with a different \
+				port-number expected $ack_nr"
+			fail_test
+			dump_stats=1
+		else
+			echo "[ ok ]"
+		fi
+
+		printf "%-${nr_blank}s %s" " " "syn"
+		count=$(get_counter ${ns1} "MPTcpExtMismatchPortSynRx")
+		if [ -z "$count" ]; then
+			echo -n "[skip]"
+		elif [ "$count" != "$mis_syn_nr" ]; then
+			echo "[fail] got $count JOIN[s] syn with a mismatched \
+				port-number expected $mis_syn_nr"
+			fail_test
+			dump_stats=1
+		else
+			echo -n "[ ok ]"
+		fi
+
+		echo -n " - ack   "
+		count=$(get_counter ${ns1} "MPTcpExtMismatchPortAckRx")
+		if [ -z "$count" ]; then
+			echo "[skip]"
+		elif [ "$count" != "$mis_ack_nr" ]; then
+			echo "[fail] got $count JOIN[s] ack with a mismatched \
+				port-number expected $mis_ack_nr"
+			fail_test
+			dump_stats=1
+		else
+			echo "[ ok ]"
+		fi
+	else
+		echo ""
+	fi
+
+	[ "${dump_stats}" = 1 ] && dump_stats
+}
+
+chk_rm_nr()
+{
+	local rm_addr_nr=$1
+	local rm_subflow_nr=$2
+	local invert
+	local simult
+	local count
+	local dump_stats
+	local addr_ns=$ns1
+	local subflow_ns=$ns2
+	local extra_msg=""
+
+	shift 2
+	while [ -n "$1" ]; do
+		[ "$1" = "invert" ] && invert=true
+		[ "$1" = "simult" ] && simult=true
+		shift
+	done
+
+	if [ -z $invert ]; then
+		addr_ns=$ns1
+		subflow_ns=$ns2
+	elif [ $invert = "true" ]; then
+		addr_ns=$ns2
+		subflow_ns=$ns1
+		extra_msg="   invert"
+	fi
+
+	printf "%-${nr_blank}s %s" " " "rm "
+	count=$(get_counter ${addr_ns} "MPTcpExtRmAddr")
+	if [ -z "$count" ]; then
+		echo -n "[skip]"
+	elif [ "$count" != "$rm_addr_nr" ]; then
+		echo "[fail] got $count RM_ADDR[s] expected $rm_addr_nr"
+		fail_test
+		dump_stats=1
+	else
+		echo -n "[ ok ]"
+	fi
+
+	echo -n " - rmsf  "
+	count=$(get_counter ${subflow_ns} "MPTcpExtRmSubflow")
+	if [ -z "$count" ]; then
+		echo -n "[skip]"
+	elif [ -n "$simult" ]; then
+		local cnt suffix
+
+		cnt=$(get_counter ${addr_ns} "MPTcpExtRmSubflow")
+
+		# in case of simult flush, the subflow removal count on each side is
+		# unreliable
+		count=$((count + cnt))
+		[ "$count" != "$rm_subflow_nr" ] && suffix="$count in [$rm_subflow_nr:$((rm_subflow_nr*2))]"
+		if [ $count -ge "$rm_subflow_nr" ] && \
+		   [ "$count" -le "$((rm_subflow_nr *2 ))" ]; then
+			echo -n "[ ok ] $suffix"
+		else
+			echo "[fail] got $count RM_SUBFLOW[s] expected in range [$rm_subflow_nr:$((rm_subflow_nr*2))]"
+			fail_test
+			dump_stats=1
+		fi
+	elif [ "$count" != "$rm_subflow_nr" ]; then
+		echo "[fail] got $count RM_SUBFLOW[s] expected $rm_subflow_nr"
+		fail_test
+		dump_stats=1
+	else
+		echo -n "[ ok ]"
+	fi
+
+	[ "${dump_stats}" = 1 ] && dump_stats
+
+	echo "$extra_msg"
+}
+
+chk_prio_nr()
+{
+	local mp_prio_nr_tx=$1
+	local mp_prio_nr_rx=$2
+	local count
+	local dump_stats
+
+	printf "%-${nr_blank}s %s" " " "ptx"
+	count=$(get_counter ${ns1} "MPTcpExtMPPrioTx")
+	if [ -z "$count" ]; then
+		echo -n "[skip]"
+	elif [ "$count" != "$mp_prio_nr_tx" ]; then
+		echo "[fail] got $count MP_PRIO[s] TX expected $mp_prio_nr_tx"
+		fail_test
+		dump_stats=1
+	else
+		echo -n "[ ok ]"
+	fi
+
+	echo -n " - prx   "
+	count=$(get_counter ${ns1} "MPTcpExtMPPrioRx")
+	if [ -z "$count" ]; then
+		echo "[skip]"
+	elif [ "$count" != "$mp_prio_nr_rx" ]; then
+		echo "[fail] got $count MP_PRIO[s] RX expected $mp_prio_nr_rx"
+		fail_test
+		dump_stats=1
+	else
+		echo "[ ok ]"
+	fi
+
+	[ "${dump_stats}" = 1 ] && dump_stats
+}
+
+chk_subflow_nr()
+{
+	local need_title="$1"
+	local msg="$2"
+	local subflow_nr=$3
+	local cnt1
+	local cnt2
+	local dump_stats
+
+	if [ -n "${need_title}" ]; then
+		printf "%03u %-36s %s" "${TEST_COUNT}" "${TEST_NAME}" "${msg}"
+	else
+		printf "%-${nr_blank}s %s" " " "${msg}"
+	fi
+
+	cnt1=$(ss -N $ns1 -tOni | grep -c token)
+	cnt2=$(ss -N $ns2 -tOni | grep -c token)
+	if [ "$cnt1" != "$subflow_nr" ] || [ "$cnt2" != "$subflow_nr" ]; then
+		echo "[fail] got $cnt1:$cnt2 subflows expected $subflow_nr"
+		fail_test
+		dump_stats=1
+	else
+		echo "[ ok ]"
+	fi
+
+	if [ "${dump_stats}" = 1 ]; then
+		ss -N $ns1 -tOni
+		ss -N $ns1 -tOni | grep token
+		ip -n $ns1 mptcp endpoint
+		dump_stats
+	fi
+}
+
+chk_link_usage()
+{
+	local ns=$1
+	local link=$2
+	local out=$3
+	local expected_rate=$4
+
+	local tx_link tx_total
+	tx_link=$(ip netns exec $ns cat /sys/class/net/$link/statistics/tx_bytes)
+	tx_total=$(stat --format=%s $out)
+	local tx_rate=$((tx_link * 100 / tx_total))
+	local tolerance=5
+
+	printf "%-${nr_blank}s %-18s" " " "link usage"
+	if [ $tx_rate -lt $((expected_rate - tolerance)) ] || \
+	   [ $tx_rate -gt $((expected_rate + tolerance)) ]; then
+		echo "[fail] got $tx_rate% usage, expected $expected_rate%"
+		fail_test
+	else
+		echo "[ ok ]"
+	fi
+}
+
+wait_attempt_fail()
+{
+	local timeout_ms=$((timeout_poll * 1000))
+	local time=0
+	local ns=$1
+
+	while [ $time -lt $timeout_ms ]; do
+		local cnt
+
+		cnt=$(get_counter ${ns} "TcpAttemptFails")
+
+		[ "$cnt" = 1 ] && return 1
+		time=$((time + 100))
+		sleep 0.1
+	done
+	return 1
+}
+
+set_userspace_pm()
+{
+	local ns=$1
+
+	ip netns exec $ns sysctl -q net.mptcp.pm_type=1
+}
+
+subflows_tests()
+{
+	if reset "no JOIN"; then
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 0 0 0
+	fi
+
+	# subflow limited by client
+	if reset "single subflow, limited by client"; then
+		pm_nl_set_limits $ns1 0 0
+		pm_nl_set_limits $ns2 0 0
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 0 0 0
+	fi
+
+	# subflow limited by server
+	if reset "single subflow, limited by server"; then
+		pm_nl_set_limits $ns1 0 0
+		pm_nl_set_limits $ns2 0 1
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 1 1 0
+	fi
+
+	# subflow
+	if reset "single subflow"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 0 1
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 1 1 1
+	fi
+
+	# multiple subflows
+	if reset "multiple subflows"; then
+		pm_nl_set_limits $ns1 0 2
+		pm_nl_set_limits $ns2 0 2
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		pm_nl_add_endpoint $ns2 10.0.2.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 2 2 2
+	fi
+
+	# multiple subflows limited by server
+	if reset "multiple subflows, limited by server"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 0 2
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		pm_nl_add_endpoint $ns2 10.0.2.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 2 2 1
+	fi
+
+	# single subflow, dev
+	if reset "single subflow, dev"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 0 1
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow dev ns2eth3
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 1 1 1
+	fi
+}
+
+subflows_error_tests()
+{
+	# If a single subflow is configured, and matches the MPC src
+	# address, no additional subflow should be created
+	if reset "no MPC reuse with single endpoint"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 0 1
+		pm_nl_add_endpoint $ns2 10.0.1.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1 0 0 0 slow
+		chk_join_nr 0 0 0
+	fi
+
+	# multiple subflows, with subflow creation error
+	if reset_with_tcp_filter "multi subflows, with failing subflow" ns1 10.0.3.2 REJECT &&
+	   continue_if mptcp_lib_kallsyms_has "mptcp_pm_subflow_check_next$"; then
+		pm_nl_set_limits $ns1 0 2
+		pm_nl_set_limits $ns2 0 2
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		pm_nl_add_endpoint $ns2 10.0.2.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1 0 0 0 slow
+		chk_join_nr 1 1 1
+	fi
+
+	# multiple subflows, with subflow timeout on MPJ
+	if reset_with_tcp_filter "multi subflows, with subflow timeout" ns1 10.0.3.2 DROP &&
+	   continue_if mptcp_lib_kallsyms_has "mptcp_pm_subflow_check_next$"; then
+		pm_nl_set_limits $ns1 0 2
+		pm_nl_set_limits $ns2 0 2
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		pm_nl_add_endpoint $ns2 10.0.2.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1 0 0 0 slow
+		chk_join_nr 1 1 1
+	fi
+
+	# multiple subflows, check that the endpoint corresponding to
+	# closed subflow (due to reset) is not reused if additional
+	# subflows are added later
+	if reset_with_tcp_filter "multi subflows, fair usage on close" ns1 10.0.3.2 REJECT &&
+	   continue_if mptcp_lib_kallsyms_has "mptcp_pm_subflow_check_next$"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 0 1
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1 0 0 0 slow &
+
+		# mpj subflow will be in TW after the reset
+		wait_attempt_fail $ns2
+		pm_nl_add_endpoint $ns2 10.0.2.2 flags subflow
+		wait
+
+		# additional subflow could be created only if the PM select
+		# the later endpoint, skipping the already used one
+		chk_join_nr 1 1 1
+	fi
+}
+
+signal_address_tests()
+{
+	# add_address, unused
+	if reset "unused signal address"; then
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 0 0 0
+		chk_add_nr 1 1
+	fi
+
+	# accept and use add_addr
+	if reset "signal address"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 1 1
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 1 1 1
+		chk_add_nr 1 1
+	fi
+
+	# accept and use add_addr with an additional subflow
+	# note: signal address in server ns and local addresses in client ns must
+	# belong to different subnets or one of the listed local address could be
+	# used for 'add_addr' subflow
+	if reset "subflow and signal"; then
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		pm_nl_set_limits $ns1 0 2
+		pm_nl_set_limits $ns2 1 2
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 2 2 2
+		chk_add_nr 1 1
+	fi
+
+	# accept and use add_addr with additional subflows
+	if reset "multiple subflows and signal"; then
+		pm_nl_set_limits $ns1 0 3
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		pm_nl_set_limits $ns2 1 3
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		pm_nl_add_endpoint $ns2 10.0.4.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 3 3 3
+		chk_add_nr 1 1
+	fi
+
+	# signal addresses
+	if reset "signal addresses"; then
+		pm_nl_set_limits $ns1 3 3
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		pm_nl_add_endpoint $ns1 10.0.3.1 flags signal
+		pm_nl_add_endpoint $ns1 10.0.4.1 flags signal
+		pm_nl_set_limits $ns2 3 3
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 3 3 3
+		chk_add_nr 3 3
+	fi
+
+	# signal invalid addresses
+	if reset "signal invalid addresses"; then
+		pm_nl_set_limits $ns1 3 3
+		pm_nl_add_endpoint $ns1 10.0.12.1 flags signal
+		pm_nl_add_endpoint $ns1 10.0.3.1 flags signal
+		pm_nl_add_endpoint $ns1 10.0.14.1 flags signal
+		pm_nl_set_limits $ns2 3 3
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 1 1 1
+		chk_add_nr 3 3
+	fi
+
+	# signal addresses race test
+	if reset "signal addresses race test"; then
+		pm_nl_set_limits $ns1 4 4
+		pm_nl_set_limits $ns2 4 4
+		pm_nl_add_endpoint $ns1 10.0.1.1 flags signal
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		pm_nl_add_endpoint $ns1 10.0.3.1 flags signal
+		pm_nl_add_endpoint $ns1 10.0.4.1 flags signal
+		pm_nl_add_endpoint $ns2 10.0.1.2 flags signal
+		pm_nl_add_endpoint $ns2 10.0.2.2 flags signal
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags signal
+		pm_nl_add_endpoint $ns2 10.0.4.2 flags signal
+
+		# the peer could possibly miss some addr notification, allow retransmission
+		ip netns exec $ns1 sysctl -q net.mptcp.add_addr_timeout=1
+		run_tests $ns1 $ns2 10.0.1.1 0 0 0 slow
+
+		# It is not directly linked to the commit introducing this
+		# symbol but for the parent one which is linked anyway.
+		if ! mptcp_lib_kallsyms_has "mptcp_pm_subflow_check_next$"; then
+			chk_join_nr 3 3 2
+			chk_add_nr 4 4
+		else
+			chk_join_nr 3 3 3
+			# the server will not signal the address terminating
+			# the MPC subflow
+			chk_add_nr 3 3
+		fi
+	fi
+}
+
+link_failure_tests()
+{
+	# accept and use add_addr with additional subflows and link loss
+	if reset "multiple flows, signal, link failure"; then
+		# without any b/w limit each veth could spool the packets and get
+		# them acked at xmit time, so that the corresponding subflow will
+		# have almost always no outstanding pkts, the scheduler will pick
+		# always the first subflow and we will have hard time testing
+		# active backup and link switch-over.
+		# Let's set some arbitrary (low) virtual link limits.
+		init_shapers
+		pm_nl_set_limits $ns1 0 3
+		pm_nl_add_endpoint $ns1 10.0.2.1 dev ns1eth2 flags signal
+		pm_nl_set_limits $ns2 1 3
+		pm_nl_add_endpoint $ns2 10.0.3.2 dev ns2eth3 flags subflow
+		pm_nl_add_endpoint $ns2 10.0.4.2 dev ns2eth4 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1 1
+		chk_join_nr 3 3 3
+		chk_add_nr 1 1
+		chk_stale_nr $ns2 1 5 1
+	fi
+
+	# accept and use add_addr with additional subflows and link loss
+	# for bidirectional transfer
+	if reset "multi flows, signal, bidi, link fail"; then
+		init_shapers
+		pm_nl_set_limits $ns1 0 3
+		pm_nl_add_endpoint $ns1 10.0.2.1 dev ns1eth2 flags signal
+		pm_nl_set_limits $ns2 1 3
+		pm_nl_add_endpoint $ns2 10.0.3.2 dev ns2eth3 flags subflow
+		pm_nl_add_endpoint $ns2 10.0.4.2 dev ns2eth4 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1 2
+		chk_join_nr 3 3 3
+		chk_add_nr 1 1
+		chk_stale_nr $ns2 1 -1 1
+	fi
+
+	# 2 subflows plus 1 backup subflow with a lossy link, backup
+	# will never be used
+	if reset "backup subflow unused, link failure"; then
+		init_shapers
+		pm_nl_set_limits $ns1 0 2
+		pm_nl_add_endpoint $ns1 10.0.2.1 dev ns1eth2 flags signal
+		pm_nl_set_limits $ns2 1 2
+		pm_nl_add_endpoint $ns2 10.0.3.2 dev ns2eth3 flags subflow,backup
+		FAILING_LINKS="1" \
+			run_tests $ns1 $ns2 10.0.1.1 1
+		chk_join_nr 2 2 2
+		chk_add_nr 1 1
+		chk_link_usage $ns2 ns2eth3 $cinsent 0
+	fi
+
+	# 2 lossy links after half transfer, backup will get half of
+	# the traffic
+	if reset "backup flow used, multi links fail"; then
+		init_shapers
+		pm_nl_set_limits $ns1 0 2
+		pm_nl_add_endpoint $ns1 10.0.2.1 dev ns1eth2 flags signal
+		pm_nl_set_limits $ns2 1 2
+		pm_nl_add_endpoint $ns2 10.0.3.2 dev ns2eth3 flags subflow,backup
+		FAILING_LINKS="1 2" \
+			run_tests $ns1 $ns2 10.0.1.1 1
+		chk_join_nr 2 2 2
+		chk_add_nr 1 1
+		chk_stale_nr $ns2 2 4 2
+		chk_link_usage $ns2 ns2eth3 $cinsent 50
+	fi
+
+	# use a backup subflow with the first subflow on a lossy link
+	# for bidirectional transfer
+	if reset "backup flow used, bidi, link failure"; then
+		init_shapers
+		pm_nl_set_limits $ns1 0 2
+		pm_nl_add_endpoint $ns1 10.0.2.1 dev ns1eth2 flags signal
+		pm_nl_set_limits $ns2 1 3
+		pm_nl_add_endpoint $ns2 10.0.3.2 dev ns2eth3 flags subflow,backup
+		FAILING_LINKS="1 2" \
+			run_tests $ns1 $ns2 10.0.1.1 2
+		chk_join_nr 2 2 2
+		chk_add_nr 1 1
+		chk_stale_nr $ns2 1 -1 2
+		chk_link_usage $ns2 ns2eth3 $cinsent 50
+	fi
+}
+
+add_addr_timeout_tests()
+{
+	# add_addr timeout
+	if reset_with_add_addr_timeout "signal address, ADD_ADDR timeout"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 1 1
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		run_tests $ns1 $ns2 10.0.1.1 0 0 0 slow
+		chk_join_nr 1 1 1
+		chk_add_nr 4 0
+	fi
+
+	# add_addr timeout IPv6
+	if reset_with_add_addr_timeout "signal address, ADD_ADDR6 timeout" 6; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 1 1
+		pm_nl_add_endpoint $ns1 dead:beef:2::1 flags signal
+		run_tests $ns1 $ns2 dead:beef:1::1 0 0 0 slow
+		chk_join_nr 1 1 1
+		chk_add_nr 4 0
+	fi
+
+	# signal addresses timeout
+	if reset_with_add_addr_timeout "signal addresses, ADD_ADDR timeout"; then
+		pm_nl_set_limits $ns1 2 2
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		pm_nl_add_endpoint $ns1 10.0.3.1 flags signal
+		pm_nl_set_limits $ns2 2 2
+		run_tests $ns1 $ns2 10.0.1.1 0 0 0 speed_10
+		chk_join_nr 2 2 2
+		chk_add_nr 8 0
+	fi
+
+	# signal invalid addresses timeout
+	if reset_with_add_addr_timeout "invalid address, ADD_ADDR timeout"; then
+		pm_nl_set_limits $ns1 2 2
+		pm_nl_add_endpoint $ns1 10.0.12.1 flags signal
+		pm_nl_add_endpoint $ns1 10.0.3.1 flags signal
+		pm_nl_set_limits $ns2 2 2
+		run_tests $ns1 $ns2 10.0.1.1 0 0 0 speed_10
+		chk_join_nr 1 1 1
+		chk_add_nr 8 0
+	fi
+}
+
+remove_tests()
+{
+	# single subflow, remove
+	if reset "remove single subflow"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 0 1
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1 0 0 -1 slow
+		chk_join_nr 1 1 1
+		chk_rm_nr 1 1
+		chk_rst_nr 0 0
+	fi
+
+	# multiple subflows, remove
+	if reset "remove multiple subflows"; then
+		pm_nl_set_limits $ns1 0 2
+		pm_nl_set_limits $ns2 0 2
+		pm_nl_add_endpoint $ns2 10.0.2.2 flags subflow
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1 0 0 -2 slow
+		chk_join_nr 2 2 2
+		chk_rm_nr 2 2
+		chk_rst_nr 0 0
+	fi
+
+	# single address, remove
+	if reset "remove single address"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		pm_nl_set_limits $ns2 1 1
+		run_tests $ns1 $ns2 10.0.1.1 0 -1 0 slow
+		chk_join_nr 1 1 1
+		chk_add_nr 1 1
+		chk_rm_nr 1 1 invert
+		chk_rst_nr 0 0
+	fi
+
+	# subflow and signal, remove
+	if reset "remove subflow and signal"; then
+		pm_nl_set_limits $ns1 0 2
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		pm_nl_set_limits $ns2 1 2
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1 0 -1 -1 slow
+		chk_join_nr 2 2 2
+		chk_add_nr 1 1
+		chk_rm_nr 1 1
+		chk_rst_nr 0 0
+	fi
+
+	# subflows and signal, remove
+	if reset "remove subflows and signal"; then
+		pm_nl_set_limits $ns1 0 3
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		pm_nl_set_limits $ns2 1 3
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		pm_nl_add_endpoint $ns2 10.0.4.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1 0 -1 -2 speed_10
+		chk_join_nr 3 3 3
+		chk_add_nr 1 1
+		chk_rm_nr 2 2
+		chk_rst_nr 0 0
+	fi
+
+	# addresses remove
+	if reset "remove addresses"; then
+		pm_nl_set_limits $ns1 3 3
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal id 250
+		pm_nl_add_endpoint $ns1 10.0.3.1 flags signal
+		pm_nl_add_endpoint $ns1 10.0.4.1 flags signal
+		pm_nl_set_limits $ns2 3 3
+		run_tests $ns1 $ns2 10.0.1.1 0 -3 0 speed_10
+		chk_join_nr 3 3 3
+		chk_add_nr 3 3
+		chk_rm_nr 3 3 invert
+		chk_rst_nr 0 0
+	fi
+
+	# invalid addresses remove
+	if reset "remove invalid addresses"; then
+		pm_nl_set_limits $ns1 3 3
+		pm_nl_add_endpoint $ns1 10.0.12.1 flags signal
+		pm_nl_add_endpoint $ns1 10.0.3.1 flags signal
+		pm_nl_add_endpoint $ns1 10.0.14.1 flags signal
+		pm_nl_set_limits $ns2 3 3
+		run_tests $ns1 $ns2 10.0.1.1 0 -3 0 speed_10
+		chk_join_nr 1 1 1
+		chk_add_nr 3 3
+		chk_rm_nr 3 1 invert
+		chk_rst_nr 0 0
+	fi
+
+	# subflows and signal, flush
+	if reset "flush subflows and signal"; then
+		pm_nl_set_limits $ns1 0 3
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		pm_nl_set_limits $ns2 1 3
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		pm_nl_add_endpoint $ns2 10.0.4.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1 0 -8 -8 slow
+		chk_join_nr 3 3 3
+		chk_add_nr 1 1
+		chk_rm_nr 1 3 invert simult
+		chk_rst_nr 0 0
+	fi
+
+	# subflows flush
+	if reset "flush subflows"; then
+		pm_nl_set_limits $ns1 3 3
+		pm_nl_set_limits $ns2 3 3
+		pm_nl_add_endpoint $ns2 10.0.2.2 flags subflow id 150
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		pm_nl_add_endpoint $ns2 10.0.4.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1 0 -8 -8 slow
+		chk_join_nr 3 3 3
+
+		if mptcp_lib_kversion_ge 5.18; then
+			chk_rm_nr 0 3 simult
+		else
+			chk_rm_nr 3 3
+		fi
+		chk_rst_nr 0 0
+	fi
+
+	# addresses flush
+	if reset "flush addresses"; then
+		pm_nl_set_limits $ns1 3 3
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal id 250
+		pm_nl_add_endpoint $ns1 10.0.3.1 flags signal
+		pm_nl_add_endpoint $ns1 10.0.4.1 flags signal
+		pm_nl_set_limits $ns2 3 3
+		run_tests $ns1 $ns2 10.0.1.1 0 -8 -8 slow
+		chk_join_nr 3 3 3
+		chk_add_nr 3 3
+		chk_rm_nr 3 3 invert simult
+		chk_rst_nr 0 0
+	fi
+
+	# invalid addresses flush
+	if reset "flush invalid addresses"; then
+		pm_nl_set_limits $ns1 3 3
+		pm_nl_add_endpoint $ns1 10.0.12.1 flags signal
+		pm_nl_add_endpoint $ns1 10.0.3.1 flags signal
+		pm_nl_add_endpoint $ns1 10.0.14.1 flags signal
+		pm_nl_set_limits $ns2 3 3
+		run_tests $ns1 $ns2 10.0.1.1 0 -8 0 slow
+		chk_join_nr 1 1 1
+		chk_add_nr 3 3
+		chk_rm_nr 3 1 invert
+		chk_rst_nr 0 0
+	fi
+
+	# remove id 0 subflow
+	if reset "remove id 0 subflow"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 0 1
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1 0 0 -9 slow
+		chk_join_nr 1 1 1
+		chk_rm_nr 1 1
+		chk_rst_nr 0 0
+	fi
+
+	# remove id 0 address
+	if reset "remove id 0 address"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		pm_nl_set_limits $ns2 1 1
+		run_tests $ns1 $ns2 10.0.1.1 0 -9 0 slow
+		chk_join_nr 1 1 1
+		chk_add_nr 1 1
+		chk_rm_nr 1 1 invert
+		chk_rst_nr 0 0 invert
+	fi
+}
+
+add_tests()
+{
+	# add single subflow
+	if reset "add single subflow"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 0 1
+		run_tests $ns1 $ns2 10.0.1.1 0 0 1 slow
+		chk_join_nr 1 1 1
+	fi
+
+	# add signal address
+	if reset "add signal address"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 1 1
+		run_tests $ns1 $ns2 10.0.1.1 0 1 0 slow
+		chk_join_nr 1 1 1
+		chk_add_nr 1 1
+	fi
+
+	# add multiple subflows
+	if reset "add multiple subflows"; then
+		pm_nl_set_limits $ns1 0 2
+		pm_nl_set_limits $ns2 0 2
+		run_tests $ns1 $ns2 10.0.1.1 0 0 2 slow
+		chk_join_nr 2 2 2
+	fi
+
+	# add multiple subflows IPv6
+	if reset "add multiple subflows IPv6"; then
+		pm_nl_set_limits $ns1 0 2
+		pm_nl_set_limits $ns2 0 2
+		run_tests $ns1 $ns2 dead:beef:1::1 0 0 2 slow
+		chk_join_nr 2 2 2
+	fi
+
+	# add multiple addresses IPv6
+	if reset "add multiple addresses IPv6"; then
+		pm_nl_set_limits $ns1 0 2
+		pm_nl_set_limits $ns2 2 2
+		run_tests $ns1 $ns2 dead:beef:1::1 0 2 0 slow
+		chk_join_nr 2 2 2
+		chk_add_nr 2 2
+	fi
+}
+
+ipv6_tests()
+{
+	# subflow IPv6
+	if reset "single subflow IPv6"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 0 1
+		pm_nl_add_endpoint $ns2 dead:beef:3::2 dev ns2eth3 flags subflow
+		run_tests $ns1 $ns2 dead:beef:1::1 0 0 0 slow
+		chk_join_nr 1 1 1
+	fi
+
+	# add_address, unused IPv6
+	if reset "unused signal address IPv6"; then
+		pm_nl_add_endpoint $ns1 dead:beef:2::1 flags signal
+		run_tests $ns1 $ns2 dead:beef:1::1 0 0 0 slow
+		chk_join_nr 0 0 0
+		chk_add_nr 1 1
+	fi
+
+	# signal address IPv6
+	if reset "single address IPv6"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_add_endpoint $ns1 dead:beef:2::1 flags signal
+		pm_nl_set_limits $ns2 1 1
+		run_tests $ns1 $ns2 dead:beef:1::1 0 0 0 slow
+		chk_join_nr 1 1 1
+		chk_add_nr 1 1
+	fi
+
+	# single address IPv6, remove
+	if reset "remove single address IPv6"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_add_endpoint $ns1 dead:beef:2::1 flags signal
+		pm_nl_set_limits $ns2 1 1
+		run_tests $ns1 $ns2 dead:beef:1::1 0 -1 0 slow
+		chk_join_nr 1 1 1
+		chk_add_nr 1 1
+		chk_rm_nr 1 1 invert
+	fi
+
+	# subflow and signal IPv6, remove
+	if reset "remove subflow and signal IPv6"; then
+		pm_nl_set_limits $ns1 0 2
+		pm_nl_add_endpoint $ns1 dead:beef:2::1 flags signal
+		pm_nl_set_limits $ns2 1 2
+		pm_nl_add_endpoint $ns2 dead:beef:3::2 dev ns2eth3 flags subflow
+		run_tests $ns1 $ns2 dead:beef:1::1 0 -1 -1 slow
+		chk_join_nr 2 2 2
+		chk_add_nr 1 1
+		chk_rm_nr 1 1
+	fi
+}
+
+v4mapped_tests()
+{
+	# subflow IPv4-mapped to IPv4-mapped
+	if reset "single subflow IPv4-mapped"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 0 1
+		pm_nl_add_endpoint $ns2 "::ffff:10.0.3.2" flags subflow
+		run_tests $ns1 $ns2 "::ffff:10.0.1.1"
+		chk_join_nr 1 1 1
+	fi
+
+	# signal address IPv4-mapped with IPv4-mapped sk
+	if reset "signal address IPv4-mapped"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 1 1
+		pm_nl_add_endpoint $ns1 "::ffff:10.0.2.1" flags signal
+		run_tests $ns1 $ns2 "::ffff:10.0.1.1"
+		chk_join_nr 1 1 1
+		chk_add_nr 1 1
+	fi
+
+	# subflow v4-map-v6
+	if reset "single subflow v4-map-v6"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 0 1
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		run_tests $ns1 $ns2 "::ffff:10.0.1.1"
+		chk_join_nr 1 1 1
+	fi
+
+	# signal address v4-map-v6
+	if reset "signal address v4-map-v6"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 1 1
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		run_tests $ns1 $ns2 "::ffff:10.0.1.1"
+		chk_join_nr 1 1 1
+		chk_add_nr 1 1
+	fi
+
+	# subflow v6-map-v4
+	if reset "single subflow v6-map-v4"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 0 1
+		pm_nl_add_endpoint $ns2 "::ffff:10.0.3.2" flags subflow
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 1 1 1
+	fi
+
+	# signal address v6-map-v4
+	if reset "signal address v6-map-v4"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 1 1
+		pm_nl_add_endpoint $ns1 "::ffff:10.0.2.1" flags signal
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 1 1 1
+		chk_add_nr 1 1
+	fi
+
+	# no subflow IPv6 to v4 address
+	if reset "no JOIN with diff families v4-v6"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 0 1
+		pm_nl_add_endpoint $ns2 dead:beef:2::2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 0 0 0
+	fi
+
+	# no subflow IPv6 to v4 address even if v6 has a valid v4 at the end
+	if reset "no JOIN with diff families v4-v6-2"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 0 1
+		pm_nl_add_endpoint $ns2 dead:beef:2::10.0.3.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 0 0 0
+	fi
+
+	# no subflow IPv4 to v6 address, no need to slow down too then
+	if reset "no JOIN with diff families v6-v4"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 0 1
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		run_tests $ns1 $ns2 dead:beef:1::1
+		chk_join_nr 0 0 0
+	fi
+}
+
+backup_tests()
+{
+	# single subflow, backup
+	if reset "single subflow, backup" &&
+	   continue_if mptcp_lib_kallsyms_has "subflow_rebuild_header$"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 0 1
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow,backup
+		run_tests $ns1 $ns2 10.0.1.1 0 0 0 slow nobackup
+		chk_join_nr 1 1 1
+		chk_prio_nr 0 1
+	fi
+
+	# single address, backup
+	if reset "single address, backup" &&
+	   continue_if mptcp_lib_kallsyms_has "subflow_rebuild_header$"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		pm_nl_set_limits $ns2 1 1
+		run_tests $ns1 $ns2 10.0.1.1 0 0 0 slow backup
+		chk_join_nr 1 1 1
+		chk_add_nr 1 1
+		chk_prio_nr 1 1
+	fi
+
+	# single address with port, backup
+	if reset "single address with port, backup" &&
+	   continue_if mptcp_lib_kallsyms_has "subflow_rebuild_header$"; 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
+		run_tests $ns1 $ns2 10.0.1.1 0 0 0 slow backup
+		chk_join_nr 1 1 1
+		chk_add_nr 1 1
+		chk_prio_nr 1 1
+	fi
+
+	if reset "mpc backup" &&
+	   continue_if mptcp_lib_kallsyms_doesnt_have "T mptcp_subflow_send_ack$"; then
+		pm_nl_add_endpoint $ns2 10.0.1.2 flags subflow,backup
+		run_tests $ns1 $ns2 10.0.1.1 0 0 0 slow
+		chk_join_nr 0 0 0
+		chk_prio_nr 0 1
+	fi
+
+	if reset "mpc backup both sides" &&
+	   continue_if mptcp_lib_kallsyms_doesnt_have "T mptcp_subflow_send_ack$"; then
+		pm_nl_add_endpoint $ns1 10.0.1.1 flags subflow,backup
+		pm_nl_add_endpoint $ns2 10.0.1.2 flags subflow,backup
+		run_tests $ns1 $ns2 10.0.1.1 0 0 0 slow
+		chk_join_nr 0 0 0
+		chk_prio_nr 1 1
+	fi
+
+	if reset "mpc switch to backup" &&
+	   continue_if mptcp_lib_kallsyms_doesnt_have "T mptcp_subflow_send_ack$"; then
+		pm_nl_add_endpoint $ns2 10.0.1.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1 0 0 0 slow backup
+		chk_join_nr 0 0 0
+		chk_prio_nr 0 1
+	fi
+
+	if reset "mpc switch to backup both sides" &&
+	   continue_if mptcp_lib_kallsyms_doesnt_have "T mptcp_subflow_send_ack$"; then
+		pm_nl_add_endpoint $ns1 10.0.1.1 flags subflow
+		pm_nl_add_endpoint $ns2 10.0.1.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1 0 0 0 slow backup
+		chk_join_nr 0 0 0
+		chk_prio_nr 1 1
+	fi
+}
+
+add_addr_ports_tests()
+{
+	# signal address with port
+	if reset "signal address with port"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 1 1
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal port 10100
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 1 1 1
+		chk_add_nr 1 1 1
+	fi
+
+	# subflow and signal with port
+	if reset "subflow and signal with port"; then
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal port 10100
+		pm_nl_set_limits $ns1 0 2
+		pm_nl_set_limits $ns2 1 2
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 2 2 2
+		chk_add_nr 1 1 1
+	fi
+
+	# single address with port, remove
+	if reset "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
+		run_tests $ns1 $ns2 10.0.1.1 0 -1 0 slow
+		chk_join_nr 1 1 1
+		chk_add_nr 1 1 1
+		chk_rm_nr 1 1 invert
+	fi
+
+	# subflow and signal with port, remove
+	if reset "remove subflow and signal with port"; then
+		pm_nl_set_limits $ns1 0 2
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal port 10100
+		pm_nl_set_limits $ns2 1 2
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1 0 -1 -1 slow
+		chk_join_nr 2 2 2
+		chk_add_nr 1 1 1
+		chk_rm_nr 1 1
+	fi
+
+	# subflows and signal with port, flush
+	if reset "flush subflows and signal with port"; then
+		pm_nl_set_limits $ns1 0 3
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal port 10100
+		pm_nl_set_limits $ns2 1 3
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		pm_nl_add_endpoint $ns2 10.0.4.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1 0 -8 -2 slow
+		chk_join_nr 3 3 3
+		chk_add_nr 1 1
+		chk_rm_nr 1 3 invert simult
+	fi
+
+	# multiple addresses with port
+	if reset "multiple addresses with port"; then
+		pm_nl_set_limits $ns1 2 2
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal port 10100
+		pm_nl_add_endpoint $ns1 10.0.3.1 flags signal port 10100
+		pm_nl_set_limits $ns2 2 2
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 2 2 2
+		chk_add_nr 2 2 2
+	fi
+
+	# multiple addresses with ports
+	if reset "multiple addresses with ports"; then
+		pm_nl_set_limits $ns1 2 2
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal port 10100
+		pm_nl_add_endpoint $ns1 10.0.3.1 flags signal port 10101
+		pm_nl_set_limits $ns2 2 2
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 2 2 2
+		chk_add_nr 2 2 2
+	fi
+}
+
+syncookies_tests()
+{
+	# single subflow, syncookies
+	if reset_with_cookies "single subflow with syn cookies"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 0 1
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 1 1 1
+	fi
+
+	# multiple subflows with syn cookies
+	if reset_with_cookies "multiple subflows with syn cookies"; then
+		pm_nl_set_limits $ns1 0 2
+		pm_nl_set_limits $ns2 0 2
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		pm_nl_add_endpoint $ns2 10.0.2.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 2 2 2
+	fi
+
+	# multiple subflows limited by server
+	if reset_with_cookies "subflows limited by server w cookies"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 0 2
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		pm_nl_add_endpoint $ns2 10.0.2.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 2 1 1
+	fi
+
+	# test signal address with cookies
+	if reset_with_cookies "signal address with syn cookies"; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 1 1
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 1 1 1
+		chk_add_nr 1 1
+	fi
+
+	# test cookie with subflow and signal
+	if reset_with_cookies "subflow and signal w cookies"; then
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		pm_nl_set_limits $ns1 0 2
+		pm_nl_set_limits $ns2 1 2
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 2 2 2
+		chk_add_nr 1 1
+	fi
+
+	# accept and use add_addr with additional subflows
+	if reset_with_cookies "subflows and signal w. cookies"; then
+		pm_nl_set_limits $ns1 0 3
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		pm_nl_set_limits $ns2 1 3
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		pm_nl_add_endpoint $ns2 10.0.4.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 3 3 3
+		chk_add_nr 1 1
+	fi
+}
+
+checksum_tests()
+{
+	# checksum test 0 0
+	if reset_with_checksum 0 0; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 0 1
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 0 0 0
+	fi
+
+	# checksum test 1 1
+	if reset_with_checksum 1 1; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 0 1
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 0 0 0
+	fi
+
+	# checksum test 0 1
+	if reset_with_checksum 0 1; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 0 1
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 0 0 0
+	fi
+
+	# checksum test 1 0
+	if reset_with_checksum 1 0; then
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 0 1
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 0 0 0
+	fi
+}
+
+deny_join_id0_tests()
+{
+	# subflow allow join id0 ns1
+	if reset_with_allow_join_id0 "single subflow allow join id0 ns1" 1 0; then
+		pm_nl_set_limits $ns1 1 1
+		pm_nl_set_limits $ns2 1 1
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 1 1 1
+	fi
+
+	# subflow allow join id0 ns2
+	if reset_with_allow_join_id0 "single subflow allow join id0 ns2" 0 1; then
+		pm_nl_set_limits $ns1 1 1
+		pm_nl_set_limits $ns2 1 1
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 0 0 0
+	fi
+
+	# signal address allow join id0 ns1
+	# ADD_ADDRs are not affected by allow_join_id0 value.
+	if reset_with_allow_join_id0 "signal address allow join id0 ns1" 1 0; then
+		pm_nl_set_limits $ns1 1 1
+		pm_nl_set_limits $ns2 1 1
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 1 1 1
+		chk_add_nr 1 1
+	fi
+
+	# signal address allow join id0 ns2
+	# ADD_ADDRs are not affected by allow_join_id0 value.
+	if reset_with_allow_join_id0 "signal address allow join id0 ns2" 0 1; then
+		pm_nl_set_limits $ns1 1 1
+		pm_nl_set_limits $ns2 1 1
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 1 1 1
+		chk_add_nr 1 1
+	fi
+
+	# subflow and address allow join id0 ns1
+	if reset_with_allow_join_id0 "subflow and address allow join id0 1" 1 0; then
+		pm_nl_set_limits $ns1 2 2
+		pm_nl_set_limits $ns2 2 2
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 2 2 2
+	fi
+
+	# subflow and address allow join id0 ns2
+	if reset_with_allow_join_id0 "subflow and address allow join id0 2" 0 1; then
+		pm_nl_set_limits $ns1 2 2
+		pm_nl_set_limits $ns2 2 2
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 1 1 1
+	fi
+}
+
+fullmesh_tests()
+{
+	# fullmesh 1
+	# 2 fullmesh addrs in ns2, added before the connection,
+	# 1 non-fullmesh addr in ns1, added during the connection.
+	if reset "fullmesh test 2x1"; then
+		pm_nl_set_limits $ns1 0 4
+		pm_nl_set_limits $ns2 1 4
+		pm_nl_add_endpoint $ns2 10.0.2.2 flags subflow,fullmesh
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow,fullmesh
+		run_tests $ns1 $ns2 10.0.1.1 0 1 0 slow
+		chk_join_nr 4 4 4
+		chk_add_nr 1 1
+	fi
+
+	# fullmesh 2
+	# 1 non-fullmesh addr in ns1, added before the connection,
+	# 1 fullmesh addr in ns2, added during the connection.
+	if reset "fullmesh test 1x1"; then
+		pm_nl_set_limits $ns1 1 3
+		pm_nl_set_limits $ns2 1 3
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		run_tests $ns1 $ns2 10.0.1.1 0 0 fullmesh_1 slow
+		chk_join_nr 3 3 3
+		chk_add_nr 1 1
+	fi
+
+	# fullmesh 3
+	# 1 non-fullmesh addr in ns1, added before the connection,
+	# 2 fullmesh addrs in ns2, added during the connection.
+	if reset "fullmesh test 1x2"; then
+		pm_nl_set_limits $ns1 2 5
+		pm_nl_set_limits $ns2 1 5
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		run_tests $ns1 $ns2 10.0.1.1 0 0 fullmesh_2 slow
+		chk_join_nr 5 5 5
+		chk_add_nr 1 1
+	fi
+
+	# fullmesh 4
+	# 1 non-fullmesh addr in ns1, added before the connection,
+	# 2 fullmesh addrs in ns2, added during the connection,
+	# limit max_subflows to 4.
+	if reset "fullmesh test 1x2, limited"; then
+		pm_nl_set_limits $ns1 2 4
+		pm_nl_set_limits $ns2 1 4
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		run_tests $ns1 $ns2 10.0.1.1 0 0 fullmesh_2 slow
+		chk_join_nr 4 4 4
+		chk_add_nr 1 1
+	fi
+
+	# set fullmesh flag
+	if reset "set fullmesh flag test" &&
+	   continue_if mptcp_lib_kversion_ge 5.18; then
+		pm_nl_set_limits $ns1 4 4
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags subflow
+		pm_nl_set_limits $ns2 4 4
+		run_tests $ns1 $ns2 10.0.1.1 0 0 1 slow fullmesh
+		chk_join_nr 2 2 2
+		chk_rm_nr 0 1
+	fi
+
+	# set nofullmesh flag
+	if reset "set nofullmesh flag test" &&
+	   continue_if mptcp_lib_kversion_ge 5.18; then
+		pm_nl_set_limits $ns1 4 4
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags subflow,fullmesh
+		pm_nl_set_limits $ns2 4 4
+		run_tests $ns1 $ns2 10.0.1.1 0 0 fullmesh_1 slow nofullmesh
+		chk_join_nr 2 2 2
+		chk_rm_nr 0 1
+	fi
+
+	# set backup,fullmesh flags
+	if reset "set backup,fullmesh flags test" &&
+	   continue_if mptcp_lib_kversion_ge 5.18; then
+		pm_nl_set_limits $ns1 4 4
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags subflow
+		pm_nl_set_limits $ns2 4 4
+		run_tests $ns1 $ns2 10.0.1.1 0 0 1 slow backup,fullmesh
+		chk_join_nr 2 2 2
+		chk_prio_nr 0 1
+		chk_rm_nr 0 1
+	fi
+
+	# set nobackup,nofullmesh flags
+	if reset "set nobackup,nofullmesh flags test" &&
+	   continue_if mptcp_lib_kversion_ge 5.18; then
+		pm_nl_set_limits $ns1 4 4
+		pm_nl_set_limits $ns2 4 4
+		pm_nl_add_endpoint $ns2 10.0.2.2 flags subflow,backup,fullmesh
+		run_tests $ns1 $ns2 10.0.1.1 0 0 0 slow nobackup,nofullmesh
+		chk_join_nr 2 2 2
+		chk_prio_nr 0 1
+		chk_rm_nr 0 1
+	fi
+}
+
+fastclose_tests()
+{
+	if reset_check_counter "fastclose test" "MPTcpExtMPFastcloseTx"; then
+		run_tests $ns1 $ns2 10.0.1.1 1024 0 fastclose_client
+		chk_join_nr 0 0 0
+		chk_fclose_nr 1 1
+		chk_rst_nr 1 1 invert
+	fi
+
+	if reset_check_counter "fastclose server test" "MPTcpExtMPFastcloseRx"; then
+		run_tests $ns1 $ns2 10.0.1.1 1024 0 fastclose_server
+		chk_join_nr 0 0 0 0 0 0 1
+		chk_fclose_nr 1 1 invert
+		chk_rst_nr 1 1
+	fi
+}
+
+pedit_action_pkts()
+{
+	tc -n $ns2 -j -s action show action pedit index 100 | \
+		grep "packets" | \
+		sed 's/.*"packets":\([0-9]\+\),.*/\1/'
+}
+
+fail_tests()
+{
+	# single subflow
+	if reset_with_fail "Infinite map" 1; then
+		run_tests $ns1 $ns2 10.0.1.1 128
+		chk_join_nr 0 0 0 +1 +0 1 0 1 "$(pedit_action_pkts)"
+		chk_fail_nr 1 -1 invert
+	fi
+
+	# multiple subflows
+	if reset_with_fail "MP_FAIL MP_RST" 2; then
+		tc -n $ns2 qdisc add dev ns2eth1 root netem rate 1mbit delay 5
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 0 1
+		pm_nl_add_endpoint $ns2 10.0.2.2 dev ns2eth2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1 1024
+		chk_join_nr 1 1 1 1 0 1 1 0 "$(pedit_action_pkts)"
+	fi
+}
+
+userspace_tests()
+{
+	# userspace pm type prevents add_addr
+	if reset "userspace pm type prevents add_addr" &&
+	   continue_if mptcp_lib_has_file '/proc/sys/net/mptcp/pm_type'; then
+		set_userspace_pm $ns1
+		pm_nl_set_limits $ns1 0 2
+		pm_nl_set_limits $ns2 0 2
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 0 0 0
+		chk_add_nr 0 0
+	fi
+
+	# userspace pm type does not echo add_addr without daemon
+	if reset "userspace pm no echo w/o daemon" &&
+	   continue_if mptcp_lib_has_file '/proc/sys/net/mptcp/pm_type'; then
+		set_userspace_pm $ns2
+		pm_nl_set_limits $ns1 0 2
+		pm_nl_set_limits $ns2 0 2
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 0 0 0
+		chk_add_nr 1 0
+	fi
+
+	# userspace pm type rejects join
+	if reset "userspace pm type rejects join" &&
+	   continue_if mptcp_lib_has_file '/proc/sys/net/mptcp/pm_type'; then
+		set_userspace_pm $ns1
+		pm_nl_set_limits $ns1 1 1
+		pm_nl_set_limits $ns2 1 1
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 1 1 0
+	fi
+
+	# userspace pm type does not send join
+	if reset "userspace pm type does not send join" &&
+	   continue_if mptcp_lib_has_file '/proc/sys/net/mptcp/pm_type'; then
+		set_userspace_pm $ns2
+		pm_nl_set_limits $ns1 1 1
+		pm_nl_set_limits $ns2 1 1
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 0 0 0
+	fi
+
+	# userspace pm type prevents mp_prio
+	if reset "userspace pm type prevents mp_prio" &&
+	   continue_if mptcp_lib_has_file '/proc/sys/net/mptcp/pm_type'; then
+		set_userspace_pm $ns1
+		pm_nl_set_limits $ns1 1 1
+		pm_nl_set_limits $ns2 1 1
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1 0 0 0 slow backup
+		chk_join_nr 1 1 0
+		chk_prio_nr 0 0
+	fi
+
+	# userspace pm type prevents rm_addr
+	if reset "userspace pm type prevents rm_addr" &&
+	   continue_if mptcp_lib_has_file '/proc/sys/net/mptcp/pm_type'; then
+		set_userspace_pm $ns1
+		set_userspace_pm $ns2
+		pm_nl_set_limits $ns1 0 1
+		pm_nl_set_limits $ns2 0 1
+		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1 0 0 -1 slow
+		chk_join_nr 0 0 0
+		chk_rm_nr 0 0
+	fi
+
+	# userspace pm add & remove address
+	if reset "userspace pm add & remove address" &&
+	   continue_if mptcp_lib_has_file '/proc/sys/net/mptcp/pm_type'; 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
+	fi
+
+	# userspace pm create destroy subflow
+	if reset "userspace pm create destroy subflow" &&
+	   continue_if mptcp_lib_has_file '/proc/sys/net/mptcp/pm_type'; then
+		set_userspace_pm $ns2
+		pm_nl_set_limits $ns1 0 1
+		run_tests $ns1 $ns2 10.0.1.1 0 0 userspace_1 slow
+		chk_join_nr 1 1 1
+		chk_rm_nr 1 1
+	fi
+}
+
+endpoint_tests()
+{
+	# subflow_rebuild_header is needed to support the implicit flag
+	# userspace pm type prevents add_addr
+	if reset "implicit EP" &&
+	   mptcp_lib_kallsyms_has "subflow_rebuild_header$"; then
+		pm_nl_set_limits $ns1 2 2
+		pm_nl_set_limits $ns2 2 2
+		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal
+		run_tests $ns1 $ns2 10.0.1.1 0 0 0 slow 2>/dev/null &
+
+		wait_mpj $ns1
+		pm_nl_check_endpoint 1 "creation" \
+			$ns2 10.0.2.2 id 1 flags implicit
+
+		pm_nl_add_endpoint $ns2 10.0.2.2 id 33
+		pm_nl_check_endpoint 0 "ID change is prevented" \
+			$ns2 10.0.2.2 id 1 flags implicit
+
+		pm_nl_add_endpoint $ns2 10.0.2.2 flags signal
+		pm_nl_check_endpoint 0 "modif is allowed" \
+			$ns2 10.0.2.2 id 1 flags signal
+		kill_tests_wait
+	fi
+
+	if reset "delete and re-add" &&
+	   mptcp_lib_kallsyms_has "subflow_rebuild_header$"; then
+		pm_nl_set_limits $ns1 1 1
+		pm_nl_set_limits $ns2 1 1
+		pm_nl_add_endpoint $ns2 10.0.2.2 id 2 dev ns2eth2 flags subflow
+		run_tests $ns1 $ns2 10.0.1.1 4 0 0 speed_20 2>/dev/null &
+
+		wait_mpj $ns2
+		pm_nl_del_endpoint $ns2 2 10.0.2.2
+		sleep 0.5
+		chk_subflow_nr needtitle "after delete" 1
+
+		pm_nl_add_endpoint $ns2 10.0.2.2 dev ns2eth2 flags subflow
+		wait_mpj $ns2
+		chk_subflow_nr "" "after re-add" 2
+		kill_tests_wait
+	fi
+}
+
+# [$1: error message]
+usage()
+{
+	if [ -n "${1}" ]; then
+		echo "${1}"
+		ret=1
+	fi
+
+	echo "mptcp_join usage:"
+
+	local key
+	for key in "${!all_tests[@]}"; do
+		echo "  -${key} ${all_tests[${key}]}"
+	done
+
+	echo "  -c capture pcap files"
+	echo "  -C enable data checksum"
+	echo "  -i use ip mptcp"
+	echo "  -h help"
+
+	echo "[test ids|names]"
+
+	exit ${ret}
+}
+
+
+# Use a "simple" array to force an specific order we cannot have with an associative one
+all_tests_sorted=(
+	f@subflows_tests
+	e@subflows_error_tests
+	s@signal_address_tests
+	l@link_failure_tests
+	t@add_addr_timeout_tests
+	r@remove_tests
+	a@add_tests
+	6@ipv6_tests
+	4@v4mapped_tests
+	b@backup_tests
+	p@add_addr_ports_tests
+	k@syncookies_tests
+	S@checksum_tests
+	d@deny_join_id0_tests
+	m@fullmesh_tests
+	z@fastclose_tests
+	F@fail_tests
+	u@userspace_tests
+	I@endpoint_tests
+)
+
+all_tests_args=""
+all_tests_names=()
+for subtests in "${all_tests_sorted[@]}"; do
+	key="${subtests%@*}"
+	value="${subtests#*@}"
+
+	all_tests_args+="${key}"
+	all_tests_names+=("${value}")
+	all_tests[${key}]="${value}"
+done
+
+tests=()
+while getopts "${all_tests_args}cCih" opt; do
+	case $opt in
+		["${all_tests_args}"])
+			tests+=("${all_tests[${opt}]}")
+			;;
+		c)
+			capture=1
+			;;
+		C)
+			checksum=1
+			;;
+		i)
+			ip_mptcp=1
+			;;
+		h)
+			usage
+			;;
+		*)
+			usage "Unknown option: -${opt}"
+			;;
+	esac
+done
+
+shift $((OPTIND - 1))
+
+for arg in "${@}"; do
+	if [[ "${arg}" =~ ^[0-9]+$ ]]; then
+		only_tests_ids+=("${arg}")
+	else
+		only_tests_names+=("${arg}")
+	fi
+done
+
+if [ ${#tests[@]} -eq 0 ]; then
+	tests=("${all_tests_names[@]}")
+fi
+
+for subtests in "${tests[@]}"; do
+	"${subtests}"
+done
+
+if [ ${ret} -ne 0 ]; then
+	echo
+	echo "${#failed_tests[@]} failure(s) has(ve) been detected:"
+	for i in $(get_failed_tests_ids); do
+		echo -e "\t- ${i}: ${failed_tests[${i}]}"
+	done
+	echo
+fi
+
+exit $ret
diff --git a/tools/testing/selftests/net/mptcp/mptcp_lib.sh b/tools/testing/selftests/net/mptcp/mptcp_lib.sh
new file mode 100644
index 000000000..f32045b23
--- /dev/null
+++ b/tools/testing/selftests/net/mptcp/mptcp_lib.sh
@@ -0,0 +1,104 @@
+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+readonly KSFT_FAIL=1
+readonly KSFT_SKIP=4
+
+# SELFTESTS_MPTCP_LIB_EXPECT_ALL_FEATURES env var can be set when validating all
+# features using the last version of the kernel and the selftests to make sure
+# a test is not being skipped by mistake.
+mptcp_lib_expect_all_features() {
+	[ "${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
+		echo "SKIP: MPTCP support is not available"
+		exit ${KSFT_SKIP}
+	fi
+}
+
+mptcp_lib_check_kallsyms() {
+	if ! mptcp_lib_has_file "/proc/kallsyms"; then
+		echo "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}"
+}
diff --git a/tools/testing/selftests/net/mptcp/mptcp_sockopt.c b/tools/testing/selftests/net/mptcp/mptcp_sockopt.c
new file mode 100644
index 000000000..b35148edb
--- /dev/null
+++ b/tools/testing/selftests/net/mptcp/mptcp_sockopt.c
@@ -0,0 +1,752 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#define _GNU_SOURCE
+
+#include <assert.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <string.h>
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <inttypes.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <strings.h>
+#include <time.h>
+#include <unistd.h>
+
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+
+#include <netdb.h>
+#include <netinet/in.h>
+
+#include <linux/tcp.h>
+
+static int pf = AF_INET;
+
+#ifndef IPPROTO_MPTCP
+#define IPPROTO_MPTCP 262
+#endif
+#ifndef SOL_MPTCP
+#define SOL_MPTCP 284
+#endif
+
+#ifndef MPTCP_INFO
+struct mptcp_info {
+	__u8	mptcpi_subflows;
+	__u8	mptcpi_add_addr_signal;
+	__u8	mptcpi_add_addr_accepted;
+	__u8	mptcpi_subflows_max;
+	__u8	mptcpi_add_addr_signal_max;
+	__u8	mptcpi_add_addr_accepted_max;
+	__u32	mptcpi_flags;
+	__u32	mptcpi_token;
+	__u64	mptcpi_write_seq;
+	__u64	mptcpi_snd_una;
+	__u64	mptcpi_rcv_nxt;
+	__u8	mptcpi_local_addr_used;
+	__u8	mptcpi_local_addr_max;
+	__u8	mptcpi_csum_enabled;
+};
+
+struct mptcp_subflow_data {
+	__u32		size_subflow_data;		/* size of this structure in userspace */
+	__u32		num_subflows;			/* must be 0, set by kernel */
+	__u32		size_kernel;			/* must be 0, set by kernel */
+	__u32		size_user;			/* size of one element in data[] */
+} __attribute__((aligned(8)));
+
+struct mptcp_subflow_addrs {
+	union {
+		__kernel_sa_family_t sa_family;
+		struct sockaddr sa_local;
+		struct sockaddr_in sin_local;
+		struct sockaddr_in6 sin6_local;
+		struct __kernel_sockaddr_storage ss_local;
+	};
+	union {
+		struct sockaddr sa_remote;
+		struct sockaddr_in sin_remote;
+		struct sockaddr_in6 sin6_remote;
+		struct __kernel_sockaddr_storage ss_remote;
+	};
+};
+
+#define MPTCP_INFO		1
+#define MPTCP_TCPINFO		2
+#define MPTCP_SUBFLOW_ADDRS	3
+#endif
+
+struct so_state {
+	struct mptcp_info mi;
+	uint64_t mptcpi_rcv_delta;
+	uint64_t tcpi_rcv_delta;
+};
+
+#ifndef MIN
+#define MIN(a, b) ((a) < (b) ? (a) : (b))
+#endif
+
+static void die_perror(const char *msg)
+{
+	perror(msg);
+	exit(1);
+}
+
+static void die_usage(int r)
+{
+	fprintf(stderr, "Usage: mptcp_sockopt [-6]\n");
+	exit(r);
+}
+
+static void xerror(const char *fmt, ...)
+{
+	va_list ap;
+
+	va_start(ap, fmt);
+	vfprintf(stderr, fmt, ap);
+	va_end(ap);
+	fputc('\n', stderr);
+	exit(1);
+}
+
+static const char *getxinfo_strerr(int err)
+{
+	if (err == EAI_SYSTEM)
+		return strerror(errno);
+
+	return gai_strerror(err);
+}
+
+static void xgetaddrinfo(const char *node, const char *service,
+			 const struct addrinfo *hints,
+			 struct addrinfo **res)
+{
+	int err = getaddrinfo(node, service, hints, res);
+
+	if (err) {
+		const char *errstr = getxinfo_strerr(err);
+
+		fprintf(stderr, "Fatal: getaddrinfo(%s:%s): %s\n",
+			node ? node : "", service ? service : "", errstr);
+		exit(1);
+	}
+}
+
+static int sock_listen_mptcp(const char * const listenaddr,
+			     const char * const port)
+{
+	int sock = -1;
+	struct addrinfo hints = {
+		.ai_protocol = IPPROTO_TCP,
+		.ai_socktype = SOCK_STREAM,
+		.ai_flags = AI_PASSIVE | AI_NUMERICHOST
+	};
+
+	hints.ai_family = pf;
+
+	struct addrinfo *a, *addr;
+	int one = 1;
+
+	xgetaddrinfo(listenaddr, port, &hints, &addr);
+	hints.ai_family = pf;
+
+	for (a = addr; a; a = a->ai_next) {
+		sock = socket(a->ai_family, a->ai_socktype, IPPROTO_MPTCP);
+		if (sock < 0)
+			continue;
+
+		if (-1 == setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &one,
+				     sizeof(one)))
+			perror("setsockopt");
+
+		if (bind(sock, a->ai_addr, a->ai_addrlen) == 0)
+			break; /* success */
+
+		perror("bind");
+		close(sock);
+		sock = -1;
+	}
+
+	freeaddrinfo(addr);
+
+	if (sock < 0)
+		xerror("could not create listen socket");
+
+	if (listen(sock, 20))
+		die_perror("listen");
+
+	return sock;
+}
+
+static int sock_connect_mptcp(const char * const remoteaddr,
+			      const char * const port, int proto)
+{
+	struct addrinfo hints = {
+		.ai_protocol = IPPROTO_TCP,
+		.ai_socktype = SOCK_STREAM,
+	};
+	struct addrinfo *a, *addr;
+	int sock = -1;
+
+	hints.ai_family = pf;
+
+	xgetaddrinfo(remoteaddr, port, &hints, &addr);
+	for (a = addr; a; a = a->ai_next) {
+		sock = socket(a->ai_family, a->ai_socktype, proto);
+		if (sock < 0)
+			continue;
+
+		if (connect(sock, a->ai_addr, a->ai_addrlen) == 0)
+			break; /* success */
+
+		die_perror("connect");
+	}
+
+	if (sock < 0)
+		xerror("could not create connect socket");
+
+	freeaddrinfo(addr);
+	return sock;
+}
+
+static void parse_opts(int argc, char **argv)
+{
+	int c;
+
+	while ((c = getopt(argc, argv, "h6")) != -1) {
+		switch (c) {
+		case 'h':
+			die_usage(0);
+			break;
+		case '6':
+			pf = AF_INET6;
+			break;
+		default:
+			die_usage(1);
+			break;
+		}
+	}
+}
+
+static void do_getsockopt_bogus_sf_data(int fd, int optname)
+{
+	struct mptcp_subflow_data good_data;
+	struct bogus_data {
+		struct mptcp_subflow_data d;
+		char buf[2];
+	} bd;
+	socklen_t olen, _olen;
+	int ret;
+
+	memset(&bd, 0, sizeof(bd));
+	memset(&good_data, 0, sizeof(good_data));
+
+	olen = sizeof(good_data);
+	good_data.size_subflow_data = olen;
+
+	ret = getsockopt(fd, SOL_MPTCP, optname, &bd, &olen);
+	assert(ret < 0); /* 0 size_subflow_data */
+	assert(olen == sizeof(good_data));
+
+	bd.d = good_data;
+
+	ret = getsockopt(fd, SOL_MPTCP, optname, &bd, &olen);
+	assert(ret == 0);
+	assert(olen == sizeof(good_data));
+	assert(bd.d.num_subflows == 1);
+	assert(bd.d.size_kernel > 0);
+	assert(bd.d.size_user == 0);
+
+	bd.d = good_data;
+	_olen = rand() % olen;
+	olen = _olen;
+	ret = getsockopt(fd, SOL_MPTCP, optname, &bd, &olen);
+	assert(ret < 0);	/* bogus olen */
+	assert(olen == _olen);	/* must be unchanged */
+
+	bd.d = good_data;
+	olen = sizeof(good_data);
+	bd.d.size_kernel = 1;
+	ret = getsockopt(fd, SOL_MPTCP, optname, &bd, &olen);
+	assert(ret < 0); /* size_kernel not 0 */
+
+	bd.d = good_data;
+	olen = sizeof(good_data);
+	bd.d.num_subflows = 1;
+	ret = getsockopt(fd, SOL_MPTCP, optname, &bd, &olen);
+	assert(ret < 0); /* num_subflows not 0 */
+
+	/* forward compat check: larger struct mptcp_subflow_data on 'old' kernel */
+	bd.d = good_data;
+	olen = sizeof(bd);
+	bd.d.size_subflow_data = sizeof(bd);
+
+	ret = getsockopt(fd, SOL_MPTCP, optname, &bd, &olen);
+	assert(ret == 0);
+
+	/* olen must be truncated to real data size filled by kernel: */
+	assert(olen == sizeof(good_data));
+
+	assert(bd.d.size_subflow_data == sizeof(bd));
+
+	bd.d = good_data;
+	bd.d.size_subflow_data += 1;
+	bd.d.size_user = 1;
+	olen = bd.d.size_subflow_data + 1;
+	_olen = olen;
+
+	ret = getsockopt(fd, SOL_MPTCP, optname, &bd, &_olen);
+	assert(ret == 0);
+
+	/* no truncation, kernel should have filled 1 byte of optname payload in buf[1]: */
+	assert(olen == _olen);
+
+	assert(bd.d.size_subflow_data == sizeof(good_data) + 1);
+	assert(bd.buf[0] == 0);
+}
+
+static void do_getsockopt_mptcp_info(struct so_state *s, int fd, size_t w)
+{
+	struct mptcp_info i;
+	socklen_t olen;
+	int ret;
+
+	olen = sizeof(i);
+	ret = getsockopt(fd, SOL_MPTCP, MPTCP_INFO, &i, &olen);
+
+	if (ret < 0)
+		die_perror("getsockopt MPTCP_INFO");
+
+	assert(olen == sizeof(i));
+
+	if (s->mi.mptcpi_write_seq == 0)
+		s->mi = i;
+
+	assert(s->mi.mptcpi_write_seq + w == i.mptcpi_write_seq);
+
+	s->mptcpi_rcv_delta = i.mptcpi_rcv_nxt - s->mi.mptcpi_rcv_nxt;
+}
+
+static void do_getsockopt_tcp_info(struct so_state *s, int fd, size_t r, size_t w)
+{
+	struct my_tcp_info {
+		struct mptcp_subflow_data d;
+		struct tcp_info ti[2];
+	} ti;
+	int ret, tries = 5;
+	socklen_t olen;
+
+	do {
+		memset(&ti, 0, sizeof(ti));
+
+		ti.d.size_subflow_data = sizeof(struct mptcp_subflow_data);
+		ti.d.size_user = sizeof(struct tcp_info);
+		olen = sizeof(ti);
+
+		ret = getsockopt(fd, SOL_MPTCP, MPTCP_TCPINFO, &ti, &olen);
+		if (ret < 0)
+			xerror("getsockopt MPTCP_TCPINFO (tries %d, %m)");
+
+		assert(olen <= sizeof(ti));
+		assert(ti.d.size_kernel > 0);
+		assert(ti.d.size_user ==
+		       MIN(ti.d.size_kernel, sizeof(struct tcp_info)));
+		assert(ti.d.num_subflows == 1);
+
+		assert(olen > (socklen_t)sizeof(struct mptcp_subflow_data));
+		olen -= sizeof(struct mptcp_subflow_data);
+		assert(olen == ti.d.size_user);
+
+		if (ti.ti[0].tcpi_bytes_sent == w &&
+		    ti.ti[0].tcpi_bytes_received == r)
+			goto done;
+
+		if (r == 0 && ti.ti[0].tcpi_bytes_sent == w &&
+		    ti.ti[0].tcpi_bytes_received) {
+			s->tcpi_rcv_delta = ti.ti[0].tcpi_bytes_received;
+			goto done;
+		}
+
+		/* wait and repeat, might be that tx is still ongoing */
+		sleep(1);
+	} while (tries-- > 0);
+
+	xerror("tcpi_bytes_sent %" PRIu64 ", want %zu. tcpi_bytes_received %" PRIu64 ", want %zu",
+		ti.ti[0].tcpi_bytes_sent, w, ti.ti[0].tcpi_bytes_received, r);
+
+done:
+	do_getsockopt_bogus_sf_data(fd, MPTCP_TCPINFO);
+}
+
+static void do_getsockopt_subflow_addrs(int fd)
+{
+	struct sockaddr_storage remote, local;
+	socklen_t olen, rlen, llen;
+	int ret;
+	struct my_addrs {
+		struct mptcp_subflow_data d;
+		struct mptcp_subflow_addrs addr[2];
+	} addrs;
+
+	memset(&addrs, 0, sizeof(addrs));
+	memset(&local, 0, sizeof(local));
+	memset(&remote, 0, sizeof(remote));
+
+	addrs.d.size_subflow_data = sizeof(struct mptcp_subflow_data);
+	addrs.d.size_user = sizeof(struct mptcp_subflow_addrs);
+	olen = sizeof(addrs);
+
+	ret = getsockopt(fd, SOL_MPTCP, MPTCP_SUBFLOW_ADDRS, &addrs, &olen);
+	if (ret < 0)
+		die_perror("getsockopt MPTCP_SUBFLOW_ADDRS");
+
+	assert(olen <= sizeof(addrs));
+	assert(addrs.d.size_kernel > 0);
+	assert(addrs.d.size_user ==
+	       MIN(addrs.d.size_kernel, sizeof(struct mptcp_subflow_addrs)));
+	assert(addrs.d.num_subflows == 1);
+
+	assert(olen > (socklen_t)sizeof(struct mptcp_subflow_data));
+	olen -= sizeof(struct mptcp_subflow_data);
+	assert(olen == addrs.d.size_user);
+
+	llen = sizeof(local);
+	ret = getsockname(fd, (struct sockaddr *)&local, &llen);
+	if (ret < 0)
+		die_perror("getsockname");
+	rlen = sizeof(remote);
+	ret = getpeername(fd, (struct sockaddr *)&remote, &rlen);
+	if (ret < 0)
+		die_perror("getpeername");
+
+	assert(rlen > 0);
+	assert(rlen == llen);
+
+	assert(remote.ss_family == local.ss_family);
+
+	assert(memcmp(&local, &addrs.addr[0].ss_local, sizeof(local)) == 0);
+	assert(memcmp(&remote, &addrs.addr[0].ss_remote, sizeof(remote)) == 0);
+
+	memset(&addrs, 0, sizeof(addrs));
+
+	addrs.d.size_subflow_data = sizeof(struct mptcp_subflow_data);
+	addrs.d.size_user = sizeof(sa_family_t);
+	olen = sizeof(addrs.d) + sizeof(sa_family_t);
+
+	ret = getsockopt(fd, SOL_MPTCP, MPTCP_SUBFLOW_ADDRS, &addrs, &olen);
+	assert(ret == 0);
+	assert(olen == sizeof(addrs.d) + sizeof(sa_family_t));
+
+	assert(addrs.addr[0].sa_family == pf);
+	assert(addrs.addr[0].sa_family == local.ss_family);
+
+	assert(memcmp(&local, &addrs.addr[0].ss_local, sizeof(local)) != 0);
+	assert(memcmp(&remote, &addrs.addr[0].ss_remote, sizeof(remote)) != 0);
+
+	do_getsockopt_bogus_sf_data(fd, MPTCP_SUBFLOW_ADDRS);
+}
+
+static void do_getsockopts(struct so_state *s, int fd, size_t r, size_t w)
+{
+	do_getsockopt_mptcp_info(s, fd, w);
+
+	do_getsockopt_tcp_info(s, fd, r, w);
+
+	do_getsockopt_subflow_addrs(fd);
+}
+
+static void connect_one_server(int fd, int pipefd)
+{
+	char buf[4096], buf2[4096];
+	size_t len, i, total;
+	struct so_state s;
+	bool eof = false;
+	ssize_t ret;
+
+	memset(&s, 0, sizeof(s));
+
+	len = rand() % (sizeof(buf) - 1);
+
+	if (len < 128)
+		len = 128;
+
+	for (i = 0; i < len ; i++) {
+		buf[i] = rand() % 26;
+		buf[i] += 'A';
+	}
+
+	buf[i] = '\n';
+
+	do_getsockopts(&s, fd, 0, 0);
+
+	/* un-block server */
+	ret = read(pipefd, buf2, 4);
+	assert(ret == 4);
+	close(pipefd);
+
+	assert(strncmp(buf2, "xmit", 4) == 0);
+
+	ret = write(fd, buf, len);
+	if (ret < 0)
+		die_perror("write");
+
+	if (ret != (ssize_t)len)
+		xerror("short write");
+
+	total = 0;
+	do {
+		ret = read(fd, buf2 + total, sizeof(buf2) - total);
+		if (ret < 0)
+			die_perror("read");
+		if (ret == 0) {
+			eof = true;
+			break;
+		}
+
+		total += ret;
+	} while (total < len);
+
+	if (total != len)
+		xerror("total %lu, len %lu eof %d\n", total, len, eof);
+
+	if (memcmp(buf, buf2, len))
+		xerror("data corruption");
+
+	if (s.tcpi_rcv_delta)
+		assert(s.tcpi_rcv_delta <= total);
+
+	do_getsockopts(&s, fd, ret, ret);
+
+	if (eof)
+		total += 1; /* sequence advances due to FIN */
+
+	assert(s.mptcpi_rcv_delta == (uint64_t)total);
+	close(fd);
+}
+
+static void process_one_client(int fd, int pipefd)
+{
+	ssize_t ret, ret2, ret3;
+	struct so_state s;
+	char buf[4096];
+
+	memset(&s, 0, sizeof(s));
+	do_getsockopts(&s, fd, 0, 0);
+
+	ret = write(pipefd, "xmit", 4);
+	assert(ret == 4);
+
+	ret = read(fd, buf, sizeof(buf));
+	if (ret < 0)
+		die_perror("read");
+
+	assert(s.mptcpi_rcv_delta <= (uint64_t)ret);
+
+	if (s.tcpi_rcv_delta)
+		assert(s.tcpi_rcv_delta == (uint64_t)ret);
+
+	ret2 = write(fd, buf, ret);
+	if (ret2 < 0)
+		die_perror("write");
+
+	/* wait for hangup */
+	ret3 = read(fd, buf, 1);
+	if (ret3 != 0)
+		xerror("expected EOF, got %lu", ret3);
+
+	do_getsockopts(&s, fd, ret, ret2);
+	if (s.mptcpi_rcv_delta != (uint64_t)ret + 1)
+		xerror("mptcpi_rcv_delta %" PRIu64 ", expect %" PRIu64, s.mptcpi_rcv_delta, ret + 1, s.mptcpi_rcv_delta - ret);
+	close(fd);
+}
+
+static int xaccept(int s)
+{
+	int fd = accept(s, NULL, 0);
+
+	if (fd < 0)
+		die_perror("accept");
+
+	return fd;
+}
+
+static int server(int pipefd)
+{
+	int fd = -1, r;
+
+	switch (pf) {
+	case AF_INET:
+		fd = sock_listen_mptcp("127.0.0.1", "15432");
+		break;
+	case AF_INET6:
+		fd = sock_listen_mptcp("::1", "15432");
+		break;
+	default:
+		xerror("Unknown pf %d\n", pf);
+		break;
+	}
+
+	r = write(pipefd, "conn", 4);
+	assert(r == 4);
+
+	alarm(15);
+	r = xaccept(fd);
+
+	process_one_client(r, pipefd);
+
+	return 0;
+}
+
+static void test_ip_tos_sockopt(int fd)
+{
+	uint8_t tos_in, tos_out;
+	socklen_t s;
+	int r;
+
+	tos_in = rand() & 0xfc;
+	r = setsockopt(fd, SOL_IP, IP_TOS, &tos_in, sizeof(tos_out));
+	if (r != 0)
+		die_perror("setsockopt IP_TOS");
+
+	tos_out = 0;
+	s = sizeof(tos_out);
+	r = getsockopt(fd, SOL_IP, IP_TOS, &tos_out, &s);
+	if (r != 0)
+		die_perror("getsockopt IP_TOS");
+
+	if (tos_in != tos_out)
+		xerror("tos %x != %x socklen_t %d\n", tos_in, tos_out, s);
+
+	if (s != 1)
+		xerror("tos should be 1 byte");
+
+	s = 0;
+	r = getsockopt(fd, SOL_IP, IP_TOS, &tos_out, &s);
+	if (r != 0)
+		die_perror("getsockopt IP_TOS 0");
+	if (s != 0)
+		xerror("expect socklen_t == 0");
+
+	s = -1;
+	r = getsockopt(fd, SOL_IP, IP_TOS, &tos_out, &s);
+	if (r != -1 && errno != EINVAL)
+		die_perror("getsockopt IP_TOS did not indicate -EINVAL");
+	if (s != -1)
+		xerror("expect socklen_t == -1");
+}
+
+static int client(int pipefd)
+{
+	int fd = -1;
+
+	alarm(15);
+
+	switch (pf) {
+	case AF_INET:
+		fd = sock_connect_mptcp("127.0.0.1", "15432", IPPROTO_MPTCP);
+		break;
+	case AF_INET6:
+		fd = sock_connect_mptcp("::1", "15432", IPPROTO_MPTCP);
+		break;
+	default:
+		xerror("Unknown pf %d\n", pf);
+	}
+
+	test_ip_tos_sockopt(fd);
+
+	connect_one_server(fd, pipefd);
+
+	return 0;
+}
+
+static pid_t xfork(void)
+{
+	pid_t p = fork();
+
+	if (p < 0)
+		die_perror("fork");
+
+	return p;
+}
+
+static int rcheck(int wstatus, const char *what)
+{
+	if (WIFEXITED(wstatus)) {
+		if (WEXITSTATUS(wstatus) == 0)
+			return 0;
+		fprintf(stderr, "%s exited, status=%d\n", what, WEXITSTATUS(wstatus));
+		return WEXITSTATUS(wstatus);
+	} else if (WIFSIGNALED(wstatus)) {
+		xerror("%s killed by signal %d\n", what, WTERMSIG(wstatus));
+	} else if (WIFSTOPPED(wstatus)) {
+		xerror("%s stopped by signal %d\n", what, WSTOPSIG(wstatus));
+	}
+
+	return 111;
+}
+
+static void init_rng(void)
+{
+	int fd = open("/dev/urandom", O_RDONLY);
+
+	if (fd >= 0) {
+		unsigned int foo;
+		ssize_t ret;
+
+		/* can't fail */
+		ret = read(fd, &foo, sizeof(foo));
+		assert(ret == sizeof(foo));
+
+		close(fd);
+		srand(foo);
+	} else {
+		srand(time(NULL));
+	}
+}
+
+int main(int argc, char *argv[])
+{
+	int e1, e2, wstatus;
+	pid_t s, c, ret;
+	int pipefds[2];
+
+	parse_opts(argc, argv);
+
+	init_rng();
+
+	e1 = pipe(pipefds);
+	if (e1 < 0)
+		die_perror("pipe");
+
+	s = xfork();
+	if (s == 0)
+		return server(pipefds[1]);
+
+	close(pipefds[1]);
+
+	/* wait until server bound a socket */
+	e1 = read(pipefds[0], &e1, 4);
+	assert(e1 == 4);
+
+	c = xfork();
+	if (c == 0)
+		return client(pipefds[0]);
+
+	close(pipefds[0]);
+
+	ret = waitpid(s, &wstatus, 0);
+	if (ret == -1)
+		die_perror("waitpid");
+	e1 = rcheck(wstatus, "server");
+	ret = waitpid(c, &wstatus, 0);
+	if (ret == -1)
+		die_perror("waitpid");
+	e2 = rcheck(wstatus, "client");
+
+	return e1 ? e1 : e2;
+}
diff --git a/tools/testing/selftests/net/mptcp/mptcp_sockopt.sh b/tools/testing/selftests/net/mptcp/mptcp_sockopt.sh
new file mode 100755
index 000000000..114c4ce71
--- /dev/null
+++ b/tools/testing/selftests/net/mptcp/mptcp_sockopt.sh
@@ -0,0 +1,367 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+. "$(dirname "${0}")/mptcp_lib.sh"
+
+ret=0
+sin=""
+sout=""
+cin=""
+cout=""
+ksft_skip=4
+timeout_poll=30
+timeout_test=$((timeout_poll * 2 + 1))
+mptcp_connect=""
+do_all_tests=1
+iptables="iptables"
+ip6tables="ip6tables"
+
+add_mark_rules()
+{
+	local ns=$1
+	local m=$2
+
+	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
+
+		# RST packets might be handled by a internal dummy socket
+		ip netns exec $ns $t -A OUTPUT -p tcp --tcp-flags RST RST -m mark --mark 0 -j ACCEPT
+
+		ip netns exec $ns $t -A OUTPUT -p tcp -m mark --mark $m -j ACCEPT
+		ip netns exec $ns $t -A OUTPUT -p tcp -m mark --mark 0 -j DROP
+	done
+}
+
+init()
+{
+	rndh=$(printf %x $sec)-$(mktemp -u XXXXXX)
+
+	ns1="ns1-$rndh"
+	ns2="ns2-$rndh"
+	ns_sbox="ns_sbox-$rndh"
+
+	for netns in "$ns1" "$ns2" "$ns_sbox";do
+		ip netns add $netns || exit $ksft_skip
+		ip -net $netns link set lo up
+		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 $netns sysctl -q net.ipv4.conf.default.rp_filter=0
+	done
+
+	for i in `seq 1 4`; do
+		ip link add ns1eth$i netns "$ns1" type veth peer name ns2eth$i netns "$ns2"
+		ip -net "$ns1" addr add 10.0.$i.1/24 dev ns1eth$i
+		ip -net "$ns1" addr add dead:beef:$i::1/64 dev ns1eth$i nodad
+		ip -net "$ns1" link set ns1eth$i up
+
+		ip -net "$ns2" addr add 10.0.$i.2/24 dev ns2eth$i
+		ip -net "$ns2" addr add dead:beef:$i::2/64 dev ns2eth$i nodad
+		ip -net "$ns2" link set ns2eth$i up
+
+		# let $ns2 reach any $ns1 address from any interface
+		ip -net "$ns2" route add default via 10.0.$i.1 dev ns2eth$i metric 10$i
+
+		ip netns exec $ns1 ./pm_nl_ctl add 10.0.$i.1 flags signal
+		ip netns exec $ns1 ./pm_nl_ctl add dead:beef:$i::1 flags signal
+
+		ip netns exec $ns2 ./pm_nl_ctl add 10.0.$i.2 flags signal
+		ip netns exec $ns2 ./pm_nl_ctl add dead:beef:$i::2 flags signal
+	done
+
+	ip netns exec $ns1 ./pm_nl_ctl limits 8 8
+	ip netns exec $ns2 ./pm_nl_ctl limits 8 8
+
+	add_mark_rules $ns1 1
+	add_mark_rules $ns2 2
+}
+
+cleanup()
+{
+	for netns in "$ns1" "$ns2" "$ns_sbox"; do
+		ip netns del $netns
+	done
+	rm -f "$cin" "$cout"
+	rm -f "$sin" "$sout"
+}
+
+mptcp_lib_check_mptcp
+mptcp_lib_check_kallsyms
+
+ip -Version > /dev/null 2>&1
+if [ $? -ne 0 ];then
+	echo "SKIP: Could not run test without ip tool"
+	exit $ksft_skip
+fi
+
+# Use the legacy version if available to support old kernel versions
+if iptables-legacy -V &> /dev/null; then
+	iptables="iptables-legacy"
+	ip6tables="ip6tables-legacy"
+elif ! iptables -V &> /dev/null; then
+	echo "SKIP: Could not run all tests without iptables tool"
+	exit $ksft_skip
+elif ! ip6tables -V &> /dev/null; then
+	echo "SKIP: Could not run all tests without ip6tables tool"
+	exit $ksft_skip
+fi
+
+check_mark()
+{
+	local ns=$1
+	local af=$2
+
+	tables=${iptables}
+
+	if [ $af -eq 6 ];then
+		tables=${ip6tables}
+	fi
+
+	counters=$(ip netns exec $ns $tables -v -L OUTPUT | grep DROP)
+	values=${counters%DROP*}
+
+	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
+			ret=1
+			return 1
+		fi
+	done
+
+	return 0
+}
+
+print_file_err()
+{
+	ls -l "$1" 1>&2
+	echo "Trailing bytes are: "
+	tail -c 27 "$1"
+}
+
+check_transfer()
+{
+	in=$1
+	out=$2
+	what=$3
+
+	cmp "$in" "$out" > /dev/null 2>&1
+	if [ $? -ne 0 ] ;then
+		echo "[ FAIL ] $what does not match (in, out):"
+		print_file_err "$in"
+		print_file_err "$out"
+		ret=1
+
+		return 1
+	fi
+
+	return 0
+}
+
+# $1: IP address
+is_v6()
+{
+	[ -z "${1##*:*}" ]
+}
+
+do_transfer()
+{
+	listener_ns="$1"
+	connector_ns="$2"
+	cl_proto="$3"
+	srv_proto="$4"
+	connect_addr="$5"
+
+	port=12001
+
+	:> "$cout"
+	:> "$sout"
+
+	mptcp_connect="./mptcp_connect -r 20"
+
+	local local_addr
+	if is_v6 "${connect_addr}"; then
+		local_addr="::"
+	else
+		local_addr="0.0.0.0"
+	fi
+
+	cmsg="TIMESTAMPNS"
+	if mptcp_lib_kallsyms_has "mptcp_ioctl$"; then
+		cmsg+=",TCPINQ"
+	fi
+
+	timeout ${timeout_test} \
+		ip netns exec ${listener_ns} \
+			$mptcp_connect -t ${timeout_poll} -l -M 1 -p $port -s ${srv_proto} -c "${cmsg}" \
+				${local_addr} < "$sin" > "$sout" &
+	spid=$!
+
+	sleep 1
+
+	timeout ${timeout_test} \
+		ip netns exec ${connector_ns} \
+			$mptcp_connect -t ${timeout_poll} -M 2 -p $port -s ${cl_proto} -c "${cmsg}" \
+				$connect_addr < "$cin" > "$cout" &
+
+	cpid=$!
+
+	wait $cpid
+	retc=$?
+	wait $spid
+	rets=$?
+
+	if [ ${rets} -ne 0 ] || [ ${retc} -ne 0 ]; then
+		echo " client exit code $retc, server $rets" 1>&2
+		echo -e "\nnetns ${listener_ns} socket stat for ${port}:" 1>&2
+		ip netns exec ${listener_ns} ss -Menita 1>&2 -o "sport = :$port"
+
+		echo -e "\nnetns ${connector_ns} socket stat for ${port}:" 1>&2
+		ip netns exec ${connector_ns} ss -Menita 1>&2 -o "dport = :$port"
+
+		ret=1
+		return 1
+	fi
+
+	if [ $local_addr = "::" ];then
+		check_mark $listener_ns 6 || retc=1
+		check_mark $connector_ns 6 || retc=1
+	else
+		check_mark $listener_ns 4 || retc=1
+		check_mark $connector_ns 4 || retc=1
+	fi
+
+	check_transfer $cin $sout "file received by server"
+
+	rets=$?
+
+	if [ $retc -eq 0 ] && [ $rets -eq 0 ];then
+		return 0
+	fi
+
+	return 1
+}
+
+make_file()
+{
+	name=$1
+	who=$2
+	size=$3
+
+	dd if=/dev/urandom of="$name" bs=1024 count=$size 2> /dev/null
+	echo -e "\nMPTCP_TEST_FILE_END_MARKER" >> "$name"
+
+	echo "Created $name (size $size KB) containing data sent by $who"
+}
+
+do_mptcp_sockopt_tests()
+{
+	local lret=0
+
+	if ! mptcp_lib_kallsyms_has "mptcp_diag_fill_info$"; then
+		echo "INFO: MPTCP sockopt not supported: SKIP"
+		return
+	fi
+
+	ip netns exec "$ns_sbox" ./mptcp_sockopt
+	lret=$?
+
+	if [ $lret -ne 0 ]; then
+		echo "FAIL: SOL_MPTCP getsockopt" 1>&2
+		ret=$lret
+		return
+	fi
+
+	ip netns exec "$ns_sbox" ./mptcp_sockopt -6
+	lret=$?
+
+	if [ $lret -ne 0 ]; then
+		echo "FAIL: SOL_MPTCP getsockopt (ipv6)" 1>&2
+		ret=$lret
+		return
+	fi
+}
+
+run_tests()
+{
+	listener_ns="$1"
+	connector_ns="$2"
+	connect_addr="$3"
+	local lret=0
+
+	do_transfer ${listener_ns} ${connector_ns} MPTCP MPTCP ${connect_addr}
+
+	lret=$?
+
+	if [ $lret -ne 0 ]; then
+		ret=$lret
+		return
+	fi
+}
+
+do_tcpinq_test()
+{
+	ip netns exec "$ns1" ./mptcp_inq "$@"
+	lret=$?
+	if [ $lret -ne 0 ];then
+		ret=$lret
+		echo "FAIL: mptcp_inq $@" 1>&2
+		return $lret
+	fi
+
+	echo "PASS: TCP_INQ cmsg/ioctl $@"
+	return $lret
+}
+
+do_tcpinq_tests()
+{
+	local lret=0
+
+	ip netns exec "$ns1" ${iptables} -F
+	ip netns exec "$ns1" ${ip6tables} -F
+
+	if ! mptcp_lib_kallsyms_has "mptcp_ioctl$"; then
+		echo "INFO: TCP_INQ not supported: SKIP"
+		return
+	fi
+
+	for args in "-t tcp" "-r tcp"; do
+		do_tcpinq_test $args
+		lret=$?
+		if [ $lret -ne 0 ] ; then
+			return $lret
+		fi
+		do_tcpinq_test -6 $args
+		lret=$?
+		if [ $lret -ne 0 ] ; then
+			return $lret
+		fi
+	done
+
+	do_tcpinq_test -r tcp -t tcp
+
+	return $?
+}
+
+sin=$(mktemp)
+sout=$(mktemp)
+cin=$(mktemp)
+cout=$(mktemp)
+init
+make_file "$cin" "client" 1
+make_file "$sin" "server" 1
+trap cleanup EXIT
+
+run_tests $ns1 $ns2 10.0.1.1
+run_tests $ns1 $ns2 dead:beef:1::1
+
+if [ $ret -eq 0 ];then
+	echo "PASS: all packets had packet mark set"
+fi
+
+do_mptcp_sockopt_tests
+if [ $ret -eq 0 ];then
+	echo "PASS: SOL_MPTCP getsockopt has expected information"
+fi
+
+do_tcpinq_tests
+exit $ret
diff --git a/tools/testing/selftests/net/mptcp/pm_netlink.sh b/tools/testing/selftests/net/mptcp/pm_netlink.sh
new file mode 100755
index 000000000..d02e0d63a
--- /dev/null
+++ b/tools/testing/selftests/net/mptcp/pm_netlink.sh
@@ -0,0 +1,196 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+. "$(dirname "${0}")/mptcp_lib.sh"
+
+ksft_skip=4
+ret=0
+
+usage() {
+	echo "Usage: $0 [ -h ]"
+}
+
+
+while getopts "$optstring" option;do
+	case "$option" in
+	"h")
+		usage $0
+		exit 0
+		;;
+	"?")
+		usage $0
+		exit 1
+		;;
+	esac
+done
+
+sec=$(date +%s)
+rndh=$(printf %x $sec)-$(mktemp -u XXXXXX)
+ns1="ns1-$rndh"
+err=$(mktemp)
+ret=0
+
+cleanup()
+{
+	rm -f $err
+	ip netns del $ns1
+}
+
+mptcp_lib_check_mptcp
+
+ip -Version > /dev/null 2>&1
+if [ $? -ne 0 ];then
+	echo "SKIP: Could not run test without ip tool"
+	exit $ksft_skip
+fi
+
+trap cleanup EXIT
+
+ip netns add $ns1 || exit $ksft_skip
+ip -net $ns1 link set lo up
+ip netns exec $ns1 sysctl -q net.mptcp.enabled=1
+
+check()
+{
+	local cmd="$1"
+	local expected="$2"
+	local msg="$3"
+	local out=`$cmd 2>$err`
+	local cmd_ret=$?
+
+	printf "%-50s %s" "$msg"
+	if [ $cmd_ret -ne 0 ]; then
+		echo "[FAIL] command execution '$cmd' stderr "
+		cat $err
+		ret=1
+	elif [ "$out" = "$expected" ]; then
+		echo "[ OK ]"
+	else
+		echo -n "[FAIL] "
+		echo "expected '$expected' got '$out'"
+		ret=1
+	fi
+}
+
+check "ip netns exec $ns1 ./pm_nl_ctl dump" "" "defaults addr list"
+
+default_limits="$(ip netns exec $ns1 ./pm_nl_ctl limits)"
+if mptcp_lib_expect_all_features; then
+	check "ip netns exec $ns1 ./pm_nl_ctl limits" "accept 0
+subflows 2" "defaults limits"
+fi
+
+ip netns exec $ns1 ./pm_nl_ctl add 10.0.1.1
+ip netns exec $ns1 ./pm_nl_ctl add 10.0.1.2 flags subflow dev lo
+ip netns exec $ns1 ./pm_nl_ctl add 10.0.1.3 flags signal,backup
+check "ip netns exec $ns1 ./pm_nl_ctl get 1" "id 1 flags  10.0.1.1" "simple add/get addr"
+
+check "ip netns exec $ns1 ./pm_nl_ctl dump" \
+"id 1 flags  10.0.1.1
+id 2 flags subflow dev lo 10.0.1.2
+id 3 flags signal,backup 10.0.1.3" "dump addrs"
+
+ip netns exec $ns1 ./pm_nl_ctl del 2
+check "ip netns exec $ns1 ./pm_nl_ctl get 2" "" "simple del addr"
+check "ip netns exec $ns1 ./pm_nl_ctl dump" \
+"id 1 flags  10.0.1.1
+id 3 flags signal,backup 10.0.1.3" "dump addrs after del"
+
+ip netns exec $ns1 ./pm_nl_ctl add 10.0.1.3
+check "ip netns exec $ns1 ./pm_nl_ctl get 4" "" "duplicate addr"
+
+ip netns exec $ns1 ./pm_nl_ctl add 10.0.1.4 flags signal
+check "ip netns exec $ns1 ./pm_nl_ctl get 4" "id 4 flags signal 10.0.1.4" "id addr increment"
+
+for i in `seq 5 9`; do
+	ip netns exec $ns1 ./pm_nl_ctl add 10.0.1.$i flags signal >/dev/null 2>&1
+done
+check "ip netns exec $ns1 ./pm_nl_ctl get 9" "id 9 flags signal 10.0.1.9" "hard addr limit"
+check "ip netns exec $ns1 ./pm_nl_ctl get 10" "" "above hard addr limit"
+
+ip netns exec $ns1 ./pm_nl_ctl del 9
+for i in `seq 10 255`; do
+	ip netns exec $ns1 ./pm_nl_ctl add 10.0.0.9 id $i
+	ip netns exec $ns1 ./pm_nl_ctl del $i
+done
+check "ip netns exec $ns1 ./pm_nl_ctl dump" "id 1 flags  10.0.1.1
+id 3 flags signal,backup 10.0.1.3
+id 4 flags signal 10.0.1.4
+id 5 flags signal 10.0.1.5
+id 6 flags signal 10.0.1.6
+id 7 flags signal 10.0.1.7
+id 8 flags signal 10.0.1.8" "id limit"
+
+ip netns exec $ns1 ./pm_nl_ctl flush
+check "ip netns exec $ns1 ./pm_nl_ctl dump" "" "flush addrs"
+
+ip netns exec $ns1 ./pm_nl_ctl limits 9 1
+check "ip netns exec $ns1 ./pm_nl_ctl limits" "$default_limits" "rcv addrs above hard limit"
+
+ip netns exec $ns1 ./pm_nl_ctl limits 1 9
+check "ip netns exec $ns1 ./pm_nl_ctl limits" "$default_limits" "subflows above hard limit"
+
+ip netns exec $ns1 ./pm_nl_ctl limits 8 8
+check "ip netns exec $ns1 ./pm_nl_ctl limits" "accept 8
+subflows 8" "set limits"
+
+ip netns exec $ns1 ./pm_nl_ctl flush
+ip netns exec $ns1 ./pm_nl_ctl add 10.0.1.1
+ip netns exec $ns1 ./pm_nl_ctl add 10.0.1.2
+ip netns exec $ns1 ./pm_nl_ctl add 10.0.1.3 id 100
+ip netns exec $ns1 ./pm_nl_ctl add 10.0.1.4
+ip netns exec $ns1 ./pm_nl_ctl add 10.0.1.5 id 254
+ip netns exec $ns1 ./pm_nl_ctl add 10.0.1.6
+ip netns exec $ns1 ./pm_nl_ctl add 10.0.1.7
+ip netns exec $ns1 ./pm_nl_ctl add 10.0.1.8
+check "ip netns exec $ns1 ./pm_nl_ctl dump" "id 1 flags  10.0.1.1
+id 2 flags  10.0.1.2
+id 3 flags  10.0.1.7
+id 4 flags  10.0.1.8
+id 100 flags  10.0.1.3
+id 101 flags  10.0.1.4
+id 254 flags  10.0.1.5
+id 255 flags  10.0.1.6" "set ids"
+
+ip netns exec $ns1 ./pm_nl_ctl flush
+ip netns exec $ns1 ./pm_nl_ctl add 10.0.0.1
+ip netns exec $ns1 ./pm_nl_ctl add 10.0.0.2 id 254
+ip netns exec $ns1 ./pm_nl_ctl add 10.0.0.3
+ip netns exec $ns1 ./pm_nl_ctl add 10.0.0.4
+ip netns exec $ns1 ./pm_nl_ctl add 10.0.0.5 id 253
+ip netns exec $ns1 ./pm_nl_ctl add 10.0.0.6
+ip netns exec $ns1 ./pm_nl_ctl add 10.0.0.7
+ip netns exec $ns1 ./pm_nl_ctl add 10.0.0.8
+check "ip netns exec $ns1 ./pm_nl_ctl dump" "id 1 flags  10.0.0.1
+id 2 flags  10.0.0.4
+id 3 flags  10.0.0.6
+id 4 flags  10.0.0.7
+id 5 flags  10.0.0.8
+id 253 flags  10.0.0.5
+id 254 flags  10.0.0.2
+id 255 flags  10.0.0.3" "wrap-around ids"
+
+ip netns exec $ns1 ./pm_nl_ctl flush
+ip netns exec $ns1 ./pm_nl_ctl add 10.0.1.1 flags subflow
+ip netns exec $ns1 ./pm_nl_ctl set 10.0.1.1 flags backup
+check "ip netns exec $ns1 ./pm_nl_ctl dump" "id 1 flags \
+subflow,backup 10.0.1.1" "set flags (backup)"
+ip netns exec $ns1 ./pm_nl_ctl set 10.0.1.1 flags nobackup
+check "ip netns exec $ns1 ./pm_nl_ctl dump" "id 1 flags \
+subflow 10.0.1.1" "          (nobackup)"
+
+# fullmesh support has been added later
+ip netns exec $ns1 ./pm_nl_ctl set id 1 flags fullmesh
+if ip netns exec $ns1 ./pm_nl_ctl dump | grep -q "fullmesh" ||
+   mptcp_lib_expect_all_features; then
+	check "ip netns exec $ns1 ./pm_nl_ctl dump" "id 1 flags \
+subflow,fullmesh 10.0.1.1" "          (fullmesh)"
+	ip netns exec $ns1 ./pm_nl_ctl set id 1 flags nofullmesh
+	check "ip netns exec $ns1 ./pm_nl_ctl dump" "id 1 flags \
+subflow 10.0.1.1" "          (nofullmesh)"
+	ip netns exec $ns1 ./pm_nl_ctl set id 1 flags backup,fullmesh
+	check "ip netns exec $ns1 ./pm_nl_ctl dump" "id 1 flags \
+subflow,backup,fullmesh 10.0.1.1" "          (backup,fullmesh)"
+fi
+
+exit $ret
diff --git a/tools/testing/selftests/net/mptcp/pm_nl_ctl.c b/tools/testing/selftests/net/mptcp/pm_nl_ctl.c
new file mode 100644
index 000000000..1887bd61b
--- /dev/null
+++ b/tools/testing/selftests/net/mptcp/pm_nl_ctl.c
@@ -0,0 +1,1505 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <errno.h>
+#include <error.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <limits.h>
+
+#include <sys/socket.h>
+#include <sys/types.h>
+
+#include <arpa/inet.h>
+#include <net/if.h>
+
+#include <linux/rtnetlink.h>
+#include <linux/genetlink.h>
+
+#include "linux/mptcp.h"
+
+#ifndef MPTCP_PM_NAME
+#define MPTCP_PM_NAME		"mptcp_pm"
+#endif
+#ifndef MPTCP_PM_EVENTS
+#define MPTCP_PM_EVENTS		"mptcp_pm_events"
+#endif
+#ifndef IPPROTO_MPTCP
+#define IPPROTO_MPTCP 262
+#endif
+
+static void syntax(char *argv[])
+{
+	fprintf(stderr, "%s add|ann|rem|csf|dsf|get|set|del|flush|dump|events|listen|accept [<args>]\n", argv[0]);
+	fprintf(stderr, "\tadd [flags signal|subflow|backup|fullmesh] [id <nr>] [dev <name>] <ip>\n");
+	fprintf(stderr, "\tann <local-ip> id <local-id> token <token> [port <local-port>] [dev <name>]\n");
+	fprintf(stderr, "\trem id <local-id> token <token>\n");
+	fprintf(stderr, "\tcsf lip <local-ip> lid <local-id> rip <remote-ip> rport <remote-port> token <token>\n");
+	fprintf(stderr, "\tdsf lip <local-ip> lport <local-port> rip <remote-ip> rport <remote-port> token <token>\n");
+	fprintf(stderr, "\tdel <id> [<ip>]\n");
+	fprintf(stderr, "\tget <id>\n");
+	fprintf(stderr, "\tset [<ip>] [id <nr>] flags [no]backup|[no]fullmesh [port <nr>] [token <token>] [rip <ip>] [rport <port>]\n");
+	fprintf(stderr, "\tflush\n");
+	fprintf(stderr, "\tdump\n");
+	fprintf(stderr, "\tlimits [<rcv addr max> <subflow max>]\n");
+	fprintf(stderr, "\tevents\n");
+	fprintf(stderr, "\tlisten <local-ip> <local-port>\n");
+	exit(0);
+}
+
+static int init_genl_req(char *data, int family, int cmd, int version)
+{
+	struct nlmsghdr *nh = (void *)data;
+	struct genlmsghdr *gh;
+	int off = 0;
+
+	nh->nlmsg_type = family;
+	nh->nlmsg_flags = NLM_F_REQUEST;
+	nh->nlmsg_len = NLMSG_LENGTH(GENL_HDRLEN);
+	off += NLMSG_ALIGN(sizeof(*nh));
+
+	gh = (void *)(data + off);
+	gh->cmd = cmd;
+	gh->version = version;
+	off += NLMSG_ALIGN(sizeof(*gh));
+	return off;
+}
+
+static void nl_error(struct nlmsghdr *nh)
+{
+	struct nlmsgerr *err = (struct nlmsgerr *)NLMSG_DATA(nh);
+	int len = nh->nlmsg_len - sizeof(*nh);
+	uint32_t off;
+
+	if (len < sizeof(struct nlmsgerr))
+		error(1, 0, "netlink error message truncated %d min %ld", len,
+		      sizeof(struct nlmsgerr));
+
+	if (!err->error) {
+		/* check messages from kernel */
+		struct rtattr *attrs = (struct rtattr *)NLMSG_DATA(nh);
+
+		while (RTA_OK(attrs, len)) {
+			if (attrs->rta_type == NLMSGERR_ATTR_MSG)
+				fprintf(stderr, "netlink ext ack msg: %s\n",
+					(char *)RTA_DATA(attrs));
+			if (attrs->rta_type == NLMSGERR_ATTR_OFFS) {
+				memcpy(&off, RTA_DATA(attrs), 4);
+				fprintf(stderr, "netlink err off %d\n",
+					(int)off);
+			}
+			attrs = RTA_NEXT(attrs, len);
+		}
+	} else {
+		fprintf(stderr, "netlink error %d", err->error);
+	}
+}
+
+static int capture_events(int fd, int event_group)
+{
+	u_int8_t buffer[NLMSG_ALIGN(sizeof(struct nlmsghdr)) +
+			NLMSG_ALIGN(sizeof(struct genlmsghdr)) + 1024];
+	struct genlmsghdr *ghdr;
+	struct rtattr *attrs;
+	struct nlmsghdr *nh;
+	int ret = 0;
+	int res_len;
+	int msg_len;
+	fd_set rfds;
+
+	if (setsockopt(fd, SOL_NETLINK, NETLINK_ADD_MEMBERSHIP,
+		       &event_group, sizeof(event_group)) < 0)
+		error(1, errno, "could not join the " MPTCP_PM_EVENTS " mcast group");
+
+	do {
+		FD_ZERO(&rfds);
+		FD_SET(fd, &rfds);
+		res_len = NLMSG_ALIGN(sizeof(struct nlmsghdr)) +
+		  NLMSG_ALIGN(sizeof(struct genlmsghdr)) + 1024;
+
+		ret = select(FD_SETSIZE, &rfds, NULL, NULL, NULL);
+
+		if (ret < 0)
+			error(1, ret, "error in select() on NL socket");
+
+		res_len = recv(fd, buffer, res_len, 0);
+		if (res_len < 0)
+			error(1, res_len, "error on recv() from NL socket");
+
+		nh = (struct nlmsghdr *)buffer;
+
+		for (; NLMSG_OK(nh, res_len); nh = NLMSG_NEXT(nh, res_len)) {
+			if (nh->nlmsg_type == NLMSG_ERROR)
+				error(1, NLMSG_ERROR, "received invalid NL message");
+
+			ghdr = (struct genlmsghdr *)NLMSG_DATA(nh);
+
+			if (ghdr->cmd == 0)
+				continue;
+
+			fprintf(stderr, "type:%d", ghdr->cmd);
+
+			msg_len = nh->nlmsg_len - NLMSG_LENGTH(GENL_HDRLEN);
+
+			attrs = (struct rtattr *) ((char *) ghdr + GENL_HDRLEN);
+			while (RTA_OK(attrs, msg_len)) {
+				if (attrs->rta_type == MPTCP_ATTR_TOKEN)
+					fprintf(stderr, ",token:%u", *(__u32 *)RTA_DATA(attrs));
+				else if (attrs->rta_type == MPTCP_ATTR_FAMILY)
+					fprintf(stderr, ",family:%u", *(__u16 *)RTA_DATA(attrs));
+				else if (attrs->rta_type == MPTCP_ATTR_LOC_ID)
+					fprintf(stderr, ",loc_id:%u", *(__u8 *)RTA_DATA(attrs));
+				else if (attrs->rta_type == MPTCP_ATTR_REM_ID)
+					fprintf(stderr, ",rem_id:%u", *(__u8 *)RTA_DATA(attrs));
+				else if (attrs->rta_type == MPTCP_ATTR_SADDR4) {
+					u_int32_t saddr4 = ntohl(*(__u32 *)RTA_DATA(attrs));
+
+					fprintf(stderr, ",saddr4:%u.%u.%u.%u", saddr4 >> 24,
+					       (saddr4 >> 16) & 0xFF, (saddr4 >> 8) & 0xFF,
+					       (saddr4 & 0xFF));
+				} else if (attrs->rta_type == MPTCP_ATTR_SADDR6) {
+					char buf[INET6_ADDRSTRLEN];
+
+					if (inet_ntop(AF_INET6, RTA_DATA(attrs), buf,
+						      sizeof(buf)) != NULL)
+						fprintf(stderr, ",saddr6:%s", buf);
+				} else if (attrs->rta_type == MPTCP_ATTR_DADDR4) {
+					u_int32_t daddr4 = ntohl(*(__u32 *)RTA_DATA(attrs));
+
+					fprintf(stderr, ",daddr4:%u.%u.%u.%u", daddr4 >> 24,
+					       (daddr4 >> 16) & 0xFF, (daddr4 >> 8) & 0xFF,
+					       (daddr4 & 0xFF));
+				} else if (attrs->rta_type == MPTCP_ATTR_DADDR6) {
+					char buf[INET6_ADDRSTRLEN];
+
+					if (inet_ntop(AF_INET6, RTA_DATA(attrs), buf,
+						      sizeof(buf)) != NULL)
+						fprintf(stderr, ",daddr6:%s", buf);
+				} else if (attrs->rta_type == MPTCP_ATTR_SPORT)
+					fprintf(stderr, ",sport:%u",
+						ntohs(*(__u16 *)RTA_DATA(attrs)));
+				else if (attrs->rta_type == MPTCP_ATTR_DPORT)
+					fprintf(stderr, ",dport:%u",
+						ntohs(*(__u16 *)RTA_DATA(attrs)));
+				else if (attrs->rta_type == MPTCP_ATTR_BACKUP)
+					fprintf(stderr, ",backup:%u", *(__u8 *)RTA_DATA(attrs));
+				else if (attrs->rta_type == MPTCP_ATTR_ERROR)
+					fprintf(stderr, ",error:%u", *(__u8 *)RTA_DATA(attrs));
+				else if (attrs->rta_type == MPTCP_ATTR_SERVER_SIDE)
+					fprintf(stderr, ",server_side:%u", *(__u8 *)RTA_DATA(attrs));
+
+				attrs = RTA_NEXT(attrs, msg_len);
+			}
+		}
+		fprintf(stderr, "\n");
+	} while (1);
+
+	return 0;
+}
+
+/* do a netlink command and, if max > 0, fetch the reply  */
+static int do_nl_req(int fd, struct nlmsghdr *nh, int len, int max)
+{
+	struct sockaddr_nl nladdr = { .nl_family = AF_NETLINK };
+	socklen_t addr_len;
+	void *data = nh;
+	int rem, ret;
+	int err = 0;
+
+	nh->nlmsg_len = len;
+	ret = sendto(fd, data, len, 0, (void *)&nladdr, sizeof(nladdr));
+	if (ret != len)
+		error(1, errno, "send netlink: %uB != %uB\n", ret, len);
+	if (max == 0)
+		return 0;
+
+	addr_len = sizeof(nladdr);
+	rem = ret = recvfrom(fd, data, max, 0, (void *)&nladdr, &addr_len);
+	if (ret < 0)
+		error(1, errno, "recv netlink: %uB\n", ret);
+
+	/* Beware: the NLMSG_NEXT macro updates the 'rem' argument */
+	for (; NLMSG_OK(nh, rem); nh = NLMSG_NEXT(nh, rem)) {
+		if (nh->nlmsg_type == NLMSG_ERROR) {
+			nl_error(nh);
+			err = 1;
+		}
+	}
+	if (err)
+		error(1, 0, "bailing out due to netlink error[s]");
+	return ret;
+}
+
+static int genl_parse_getfamily(struct nlmsghdr *nlh, int *pm_family,
+				int *events_mcast_grp)
+{
+	struct genlmsghdr *ghdr = NLMSG_DATA(nlh);
+	int len = nlh->nlmsg_len;
+	struct rtattr *attrs;
+	struct rtattr *grps;
+	struct rtattr *grp;
+	int got_events_grp;
+	int got_family;
+	int grps_len;
+	int grp_len;
+
+	if (nlh->nlmsg_type != GENL_ID_CTRL)
+		error(1, errno, "Not a controller message, len=%d type=0x%x\n",
+		      nlh->nlmsg_len, nlh->nlmsg_type);
+
+	len -= NLMSG_LENGTH(GENL_HDRLEN);
+
+	if (len < 0)
+		error(1, errno, "wrong controller message len %d\n", len);
+
+	if (ghdr->cmd != CTRL_CMD_NEWFAMILY)
+		error(1, errno, "Unknown controller command %d\n", ghdr->cmd);
+
+	attrs = (struct rtattr *) ((char *) ghdr + GENL_HDRLEN);
+	got_family = 0;
+	got_events_grp = 0;
+
+	while (RTA_OK(attrs, len)) {
+		if (attrs->rta_type == CTRL_ATTR_FAMILY_ID) {
+			*pm_family = *(__u16 *)RTA_DATA(attrs);
+			got_family = 1;
+		} else if (attrs->rta_type == CTRL_ATTR_MCAST_GROUPS) {
+			grps = RTA_DATA(attrs);
+			grps_len = RTA_PAYLOAD(attrs);
+
+			while (RTA_OK(grps, grps_len)) {
+				grp = RTA_DATA(grps);
+				grp_len = RTA_PAYLOAD(grps);
+				got_events_grp = 0;
+
+				while (RTA_OK(grp, grp_len)) {
+					if (grp->rta_type == CTRL_ATTR_MCAST_GRP_ID)
+						*events_mcast_grp = *(__u32 *)RTA_DATA(grp);
+					else if (grp->rta_type == CTRL_ATTR_MCAST_GRP_NAME &&
+						 !strcmp(RTA_DATA(grp), MPTCP_PM_EVENTS))
+						got_events_grp = 1;
+
+					grp = RTA_NEXT(grp, grp_len);
+				}
+
+				if (got_events_grp)
+					break;
+
+				grps = RTA_NEXT(grps, grps_len);
+			}
+		}
+
+		if (got_family && got_events_grp)
+			return 0;
+
+		attrs = RTA_NEXT(attrs, len);
+	}
+
+	error(1, errno, "can't find CTRL_ATTR_FAMILY_ID attr");
+	return -1;
+}
+
+static int resolve_mptcp_pm_netlink(int fd, int *pm_family, int *events_mcast_grp)
+{
+	char data[NLMSG_ALIGN(sizeof(struct nlmsghdr)) +
+		  NLMSG_ALIGN(sizeof(struct genlmsghdr)) +
+		  1024];
+	struct nlmsghdr *nh;
+	struct rtattr *rta;
+	int namelen;
+	int off = 0;
+
+	memset(data, 0, sizeof(data));
+	nh = (void *)data;
+	off = init_genl_req(data, GENL_ID_CTRL, CTRL_CMD_GETFAMILY, 0);
+
+	rta = (void *)(data + off);
+	namelen = strlen(MPTCP_PM_NAME) + 1;
+	rta->rta_type = CTRL_ATTR_FAMILY_NAME;
+	rta->rta_len = RTA_LENGTH(namelen);
+	memcpy(RTA_DATA(rta), MPTCP_PM_NAME, namelen);
+	off += NLMSG_ALIGN(rta->rta_len);
+
+	do_nl_req(fd, nh, off, sizeof(data));
+	return genl_parse_getfamily((void *)data, pm_family, events_mcast_grp);
+}
+
+int dsf(int fd, int pm_family, int argc, char *argv[])
+{
+	char data[NLMSG_ALIGN(sizeof(struct nlmsghdr)) +
+		  NLMSG_ALIGN(sizeof(struct genlmsghdr)) +
+		  1024];
+	struct rtattr *rta, *addr;
+	u_int16_t family, port;
+	struct nlmsghdr *nh;
+	u_int32_t token;
+	int addr_start;
+	int off = 0;
+	int arg;
+
+	const char *params[5];
+
+	memset(params, 0, 5 * sizeof(const char *));
+
+	memset(data, 0, sizeof(data));
+	nh = (void *)data;
+	off = init_genl_req(data, pm_family, MPTCP_PM_CMD_SUBFLOW_DESTROY,
+			    MPTCP_PM_VER);
+
+	if (argc < 12)
+		syntax(argv);
+
+	/* Params recorded in this order:
+	 * <local-ip>, <local-port>, <remote-ip>, <remote-port>, <token>
+	 */
+	for (arg = 2; arg < argc; arg++) {
+		if (!strcmp(argv[arg], "lip")) {
+			if (++arg >= argc)
+				error(1, 0, " missing local IP");
+
+			params[0] = argv[arg];
+		} else if (!strcmp(argv[arg], "lport")) {
+			if (++arg >= argc)
+				error(1, 0, " missing local port");
+
+			params[1] = argv[arg];
+		} else if (!strcmp(argv[arg], "rip")) {
+			if (++arg >= argc)
+				error(1, 0, " missing remote IP");
+
+			params[2] = argv[arg];
+		} else if (!strcmp(argv[arg], "rport")) {
+			if (++arg >= argc)
+				error(1, 0, " missing remote port");
+
+			params[3] = argv[arg];
+		} else if (!strcmp(argv[arg], "token")) {
+			if (++arg >= argc)
+				error(1, 0, " missing token");
+
+			params[4] = argv[arg];
+		} else
+			error(1, 0, "unknown keyword %s", argv[arg]);
+	}
+
+	for (arg = 0; arg < 4; arg = arg + 2) {
+		/*  addr header */
+		addr_start = off;
+		addr = (void *)(data + off);
+		addr->rta_type = NLA_F_NESTED |
+			((arg == 0) ? MPTCP_PM_ATTR_ADDR : MPTCP_PM_ATTR_ADDR_REMOTE);
+		addr->rta_len = RTA_LENGTH(0);
+		off += NLMSG_ALIGN(addr->rta_len);
+
+		/*  addr data */
+		rta = (void *)(data + off);
+		if (inet_pton(AF_INET, params[arg], RTA_DATA(rta))) {
+			family = AF_INET;
+			rta->rta_type = MPTCP_PM_ADDR_ATTR_ADDR4;
+			rta->rta_len = RTA_LENGTH(4);
+		} else if (inet_pton(AF_INET6, params[arg], RTA_DATA(rta))) {
+			family = AF_INET6;
+			rta->rta_type = MPTCP_PM_ADDR_ATTR_ADDR6;
+			rta->rta_len = RTA_LENGTH(16);
+		} else
+			error(1, errno, "can't parse ip %s", params[arg]);
+		off += NLMSG_ALIGN(rta->rta_len);
+
+		/* family */
+		rta = (void *)(data + off);
+		rta->rta_type = MPTCP_PM_ADDR_ATTR_FAMILY;
+		rta->rta_len = RTA_LENGTH(2);
+		memcpy(RTA_DATA(rta), &family, 2);
+		off += NLMSG_ALIGN(rta->rta_len);
+
+		/*  port */
+		port = atoi(params[arg + 1]);
+		rta = (void *)(data + off);
+		rta->rta_type = MPTCP_PM_ADDR_ATTR_PORT;
+		rta->rta_len = RTA_LENGTH(2);
+		memcpy(RTA_DATA(rta), &port, 2);
+		off += NLMSG_ALIGN(rta->rta_len);
+
+		addr->rta_len = off - addr_start;
+	}
+
+	/* token */
+	token = strtoul(params[4], NULL, 10);
+	rta = (void *)(data + off);
+	rta->rta_type = MPTCP_PM_ATTR_TOKEN;
+	rta->rta_len = RTA_LENGTH(4);
+	memcpy(RTA_DATA(rta), &token, 4);
+	off += NLMSG_ALIGN(rta->rta_len);
+
+	do_nl_req(fd, nh, off, 0);
+
+	return 0;
+}
+
+int csf(int fd, int pm_family, int argc, char *argv[])
+{
+	char data[NLMSG_ALIGN(sizeof(struct nlmsghdr)) +
+		  NLMSG_ALIGN(sizeof(struct genlmsghdr)) +
+		  1024];
+	const char *params[5];
+	struct nlmsghdr *nh;
+	struct rtattr *addr;
+	struct rtattr *rta;
+	u_int16_t family;
+	u_int32_t token;
+	u_int16_t port;
+	int addr_start;
+	u_int8_t id;
+	int off = 0;
+	int arg;
+
+	memset(params, 0, 5 * sizeof(const char *));
+
+	memset(data, 0, sizeof(data));
+	nh = (void *)data;
+	off = init_genl_req(data, pm_family, MPTCP_PM_CMD_SUBFLOW_CREATE,
+			    MPTCP_PM_VER);
+
+	if (argc < 12)
+		syntax(argv);
+
+	/* Params recorded in this order:
+	 * <local-ip>, <local-id>, <remote-ip>, <remote-port>, <token>
+	 */
+	for (arg = 2; arg < argc; arg++) {
+		if (!strcmp(argv[arg], "lip")) {
+			if (++arg >= argc)
+				error(1, 0, " missing local IP");
+
+			params[0] = argv[arg];
+		} else if (!strcmp(argv[arg], "lid")) {
+			if (++arg >= argc)
+				error(1, 0, " missing local id");
+
+			params[1] = argv[arg];
+		} else if (!strcmp(argv[arg], "rip")) {
+			if (++arg >= argc)
+				error(1, 0, " missing remote ip");
+
+			params[2] = argv[arg];
+		} else if (!strcmp(argv[arg], "rport")) {
+			if (++arg >= argc)
+				error(1, 0, " missing remote port");
+
+			params[3] = argv[arg];
+		} else if (!strcmp(argv[arg], "token")) {
+			if (++arg >= argc)
+				error(1, 0, " missing token");
+
+			params[4] = argv[arg];
+		} else
+			error(1, 0, "unknown param %s", argv[arg]);
+	}
+
+	for (arg = 0; arg < 4; arg = arg + 2) {
+		/*  addr header */
+		addr_start = off;
+		addr = (void *)(data + off);
+		addr->rta_type = NLA_F_NESTED |
+			((arg == 0) ? MPTCP_PM_ATTR_ADDR : MPTCP_PM_ATTR_ADDR_REMOTE);
+		addr->rta_len = RTA_LENGTH(0);
+		off += NLMSG_ALIGN(addr->rta_len);
+
+		/*  addr data */
+		rta = (void *)(data + off);
+		if (inet_pton(AF_INET, params[arg], RTA_DATA(rta))) {
+			family = AF_INET;
+			rta->rta_type = MPTCP_PM_ADDR_ATTR_ADDR4;
+			rta->rta_len = RTA_LENGTH(4);
+		} else if (inet_pton(AF_INET6, params[arg], RTA_DATA(rta))) {
+			family = AF_INET6;
+			rta->rta_type = MPTCP_PM_ADDR_ATTR_ADDR6;
+			rta->rta_len = RTA_LENGTH(16);
+		} else
+			error(1, errno, "can't parse ip %s", params[arg]);
+		off += NLMSG_ALIGN(rta->rta_len);
+
+		/* family */
+		rta = (void *)(data + off);
+		rta->rta_type = MPTCP_PM_ADDR_ATTR_FAMILY;
+		rta->rta_len = RTA_LENGTH(2);
+		memcpy(RTA_DATA(rta), &family, 2);
+		off += NLMSG_ALIGN(rta->rta_len);
+
+		if (arg == 2) {
+			/*  port */
+			port = atoi(params[arg + 1]);
+			rta = (void *)(data + off);
+			rta->rta_type = MPTCP_PM_ADDR_ATTR_PORT;
+			rta->rta_len = RTA_LENGTH(2);
+			memcpy(RTA_DATA(rta), &port, 2);
+			off += NLMSG_ALIGN(rta->rta_len);
+		}
+
+		if (arg == 0) {
+			/* id */
+			id = atoi(params[arg + 1]);
+			rta = (void *)(data + off);
+			rta->rta_type = MPTCP_PM_ADDR_ATTR_ID;
+			rta->rta_len = RTA_LENGTH(1);
+			memcpy(RTA_DATA(rta), &id, 1);
+			off += NLMSG_ALIGN(rta->rta_len);
+		}
+
+		addr->rta_len = off - addr_start;
+	}
+
+	/* token */
+	token = strtoul(params[4], NULL, 10);
+	rta = (void *)(data + off);
+	rta->rta_type = MPTCP_PM_ATTR_TOKEN;
+	rta->rta_len = RTA_LENGTH(4);
+	memcpy(RTA_DATA(rta), &token, 4);
+	off += NLMSG_ALIGN(rta->rta_len);
+
+	do_nl_req(fd, nh, off, 0);
+
+	return 0;
+}
+
+int remove_addr(int fd, int pm_family, int argc, char *argv[])
+{
+	char data[NLMSG_ALIGN(sizeof(struct nlmsghdr)) +
+		  NLMSG_ALIGN(sizeof(struct genlmsghdr)) +
+		  1024];
+	struct nlmsghdr *nh;
+	struct rtattr *rta;
+	u_int32_t token;
+	u_int8_t id;
+	int off = 0;
+	int arg;
+
+	memset(data, 0, sizeof(data));
+	nh = (void *)data;
+	off = init_genl_req(data, pm_family, MPTCP_PM_CMD_REMOVE,
+			    MPTCP_PM_VER);
+
+	if (argc < 6)
+		syntax(argv);
+
+	for (arg = 2; arg < argc; arg++) {
+		if (!strcmp(argv[arg], "id")) {
+			if (++arg >= argc)
+				error(1, 0, " missing id value");
+
+			id = atoi(argv[arg]);
+			rta = (void *)(data + off);
+			rta->rta_type = MPTCP_PM_ATTR_LOC_ID;
+			rta->rta_len = RTA_LENGTH(1);
+			memcpy(RTA_DATA(rta), &id, 1);
+			off += NLMSG_ALIGN(rta->rta_len);
+		} else if (!strcmp(argv[arg], "token")) {
+			if (++arg >= argc)
+				error(1, 0, " missing token value");
+
+			token = strtoul(argv[arg], NULL, 10);
+			rta = (void *)(data + off);
+			rta->rta_type = MPTCP_PM_ATTR_TOKEN;
+			rta->rta_len = RTA_LENGTH(4);
+			memcpy(RTA_DATA(rta), &token, 4);
+			off += NLMSG_ALIGN(rta->rta_len);
+		} else
+			error(1, 0, "unknown keyword %s", argv[arg]);
+	}
+
+	do_nl_req(fd, nh, off, 0);
+	return 0;
+}
+
+int announce_addr(int fd, int pm_family, int argc, char *argv[])
+{
+	char data[NLMSG_ALIGN(sizeof(struct nlmsghdr)) +
+		  NLMSG_ALIGN(sizeof(struct genlmsghdr)) +
+		  1024];
+	u_int32_t flags = MPTCP_PM_ADDR_FLAG_SIGNAL;
+	u_int32_t token = UINT_MAX;
+	struct rtattr *rta, *addr;
+	u_int32_t id = UINT_MAX;
+	struct nlmsghdr *nh;
+	u_int16_t family;
+	int addr_start;
+	int off = 0;
+	int arg;
+
+	memset(data, 0, sizeof(data));
+	nh = (void *)data;
+	off = init_genl_req(data, pm_family, MPTCP_PM_CMD_ANNOUNCE,
+			    MPTCP_PM_VER);
+
+	if (argc < 7)
+		syntax(argv);
+
+	/* local-ip header */
+	addr_start = off;
+	addr = (void *)(data + off);
+	addr->rta_type = NLA_F_NESTED | MPTCP_PM_ATTR_ADDR;
+	addr->rta_len = RTA_LENGTH(0);
+	off += NLMSG_ALIGN(addr->rta_len);
+
+	/* local-ip data */
+	/* record addr type */
+	rta = (void *)(data + off);
+	if (inet_pton(AF_INET, argv[2], RTA_DATA(rta))) {
+		family = AF_INET;
+		rta->rta_type = MPTCP_PM_ADDR_ATTR_ADDR4;
+		rta->rta_len = RTA_LENGTH(4);
+	} else if (inet_pton(AF_INET6, argv[2], RTA_DATA(rta))) {
+		family = AF_INET6;
+		rta->rta_type = MPTCP_PM_ADDR_ATTR_ADDR6;
+		rta->rta_len = RTA_LENGTH(16);
+	} else
+		error(1, errno, "can't parse ip %s", argv[2]);
+	off += NLMSG_ALIGN(rta->rta_len);
+
+	/* addr family */
+	rta = (void *)(data + off);
+	rta->rta_type = MPTCP_PM_ADDR_ATTR_FAMILY;
+	rta->rta_len = RTA_LENGTH(2);
+	memcpy(RTA_DATA(rta), &family, 2);
+	off += NLMSG_ALIGN(rta->rta_len);
+
+	for (arg = 3; arg < argc; arg++) {
+		if (!strcmp(argv[arg], "id")) {
+			/* local-id */
+			if (++arg >= argc)
+				error(1, 0, " missing id value");
+
+			id = atoi(argv[arg]);
+			rta = (void *)(data + off);
+			rta->rta_type = MPTCP_PM_ADDR_ATTR_ID;
+			rta->rta_len = RTA_LENGTH(1);
+			memcpy(RTA_DATA(rta), &id, 1);
+			off += NLMSG_ALIGN(rta->rta_len);
+		} else if (!strcmp(argv[arg], "dev")) {
+			/* for the if_index */
+			int32_t ifindex;
+
+			if (++arg >= argc)
+				error(1, 0, " missing dev name");
+
+			ifindex = if_nametoindex(argv[arg]);
+			if (!ifindex)
+				error(1, errno, "unknown device %s", argv[arg]);
+
+			rta = (void *)(data + off);
+			rta->rta_type = MPTCP_PM_ADDR_ATTR_IF_IDX;
+			rta->rta_len = RTA_LENGTH(4);
+			memcpy(RTA_DATA(rta), &ifindex, 4);
+			off += NLMSG_ALIGN(rta->rta_len);
+		} else if (!strcmp(argv[arg], "port")) {
+			/* local-port (optional) */
+			u_int16_t port;
+
+			if (++arg >= argc)
+				error(1, 0, " missing port value");
+
+			port = atoi(argv[arg]);
+			rta = (void *)(data + off);
+			rta->rta_type = MPTCP_PM_ADDR_ATTR_PORT;
+			rta->rta_len = RTA_LENGTH(2);
+			memcpy(RTA_DATA(rta), &port, 2);
+			off += NLMSG_ALIGN(rta->rta_len);
+		} else if (!strcmp(argv[arg], "token")) {
+			/* MPTCP connection token */
+			if (++arg >= argc)
+				error(1, 0, " missing token value");
+
+			token = strtoul(argv[arg], NULL, 10);
+		} else
+			error(1, 0, "unknown keyword %s", argv[arg]);
+	}
+
+	/* addr flags */
+	rta = (void *)(data + off);
+	rta->rta_type = MPTCP_PM_ADDR_ATTR_FLAGS;
+	rta->rta_len = RTA_LENGTH(4);
+	memcpy(RTA_DATA(rta), &flags, 4);
+	off += NLMSG_ALIGN(rta->rta_len);
+
+	addr->rta_len = off - addr_start;
+
+	if (id == UINT_MAX || token == UINT_MAX)
+		error(1, 0, " missing mandatory inputs");
+
+	/* token */
+	rta = (void *)(data + off);
+	rta->rta_type = MPTCP_PM_ATTR_TOKEN;
+	rta->rta_len = RTA_LENGTH(4);
+	memcpy(RTA_DATA(rta), &token, 4);
+	off += NLMSG_ALIGN(rta->rta_len);
+
+	do_nl_req(fd, nh, off, 0);
+
+	return 0;
+}
+
+int add_addr(int fd, int pm_family, int argc, char *argv[])
+{
+	char data[NLMSG_ALIGN(sizeof(struct nlmsghdr)) +
+		  NLMSG_ALIGN(sizeof(struct genlmsghdr)) +
+		  1024];
+	struct rtattr *rta, *nest;
+	struct nlmsghdr *nh;
+	u_int32_t flags = 0;
+	u_int16_t family;
+	int nest_start;
+	u_int8_t id;
+	int off = 0;
+	int arg;
+
+	memset(data, 0, sizeof(data));
+	nh = (void *)data;
+	off = init_genl_req(data, pm_family, MPTCP_PM_CMD_ADD_ADDR,
+			    MPTCP_PM_VER);
+
+	if (argc < 3)
+		syntax(argv);
+
+	nest_start = off;
+	nest = (void *)(data + off);
+	nest->rta_type = NLA_F_NESTED | MPTCP_PM_ATTR_ADDR;
+	nest->rta_len = RTA_LENGTH(0);
+	off += NLMSG_ALIGN(nest->rta_len);
+
+	/* addr data */
+	rta = (void *)(data + off);
+	if (inet_pton(AF_INET, argv[2], RTA_DATA(rta))) {
+		family = AF_INET;
+		rta->rta_type = MPTCP_PM_ADDR_ATTR_ADDR4;
+		rta->rta_len = RTA_LENGTH(4);
+	} else if (inet_pton(AF_INET6, argv[2], RTA_DATA(rta))) {
+		family = AF_INET6;
+		rta->rta_type = MPTCP_PM_ADDR_ATTR_ADDR6;
+		rta->rta_len = RTA_LENGTH(16);
+	} else
+		error(1, errno, "can't parse ip %s", argv[2]);
+	off += NLMSG_ALIGN(rta->rta_len);
+
+	/* family */
+	rta = (void *)(data + off);
+	rta->rta_type = MPTCP_PM_ADDR_ATTR_FAMILY;
+	rta->rta_len = RTA_LENGTH(2);
+	memcpy(RTA_DATA(rta), &family, 2);
+	off += NLMSG_ALIGN(rta->rta_len);
+
+	for (arg = 3; arg < argc; arg++) {
+		if (!strcmp(argv[arg], "flags")) {
+			char *tok, *str;
+
+			/* flags */
+			if (++arg >= argc)
+				error(1, 0, " missing flags value");
+
+			/* do not support flag list yet */
+			for (str = argv[arg]; (tok = strtok(str, ","));
+			     str = NULL) {
+				if (!strcmp(tok, "subflow"))
+					flags |= MPTCP_PM_ADDR_FLAG_SUBFLOW;
+				else if (!strcmp(tok, "signal"))
+					flags |= MPTCP_PM_ADDR_FLAG_SIGNAL;
+				else if (!strcmp(tok, "backup"))
+					flags |= MPTCP_PM_ADDR_FLAG_BACKUP;
+				else if (!strcmp(tok, "fullmesh"))
+					flags |= MPTCP_PM_ADDR_FLAG_FULLMESH;
+				else
+					error(1, errno,
+					      "unknown flag %s", argv[arg]);
+			}
+
+			if (flags & MPTCP_PM_ADDR_FLAG_SIGNAL &&
+			    flags & MPTCP_PM_ADDR_FLAG_FULLMESH) {
+				error(1, errno, "error flag fullmesh");
+			}
+
+			rta = (void *)(data + off);
+			rta->rta_type = MPTCP_PM_ADDR_ATTR_FLAGS;
+			rta->rta_len = RTA_LENGTH(4);
+			memcpy(RTA_DATA(rta), &flags, 4);
+			off += NLMSG_ALIGN(rta->rta_len);
+		} else if (!strcmp(argv[arg], "id")) {
+			if (++arg >= argc)
+				error(1, 0, " missing id value");
+
+			id = atoi(argv[arg]);
+			rta = (void *)(data + off);
+			rta->rta_type = MPTCP_PM_ADDR_ATTR_ID;
+			rta->rta_len = RTA_LENGTH(1);
+			memcpy(RTA_DATA(rta), &id, 1);
+			off += NLMSG_ALIGN(rta->rta_len);
+		} else if (!strcmp(argv[arg], "dev")) {
+			int32_t ifindex;
+
+			if (++arg >= argc)
+				error(1, 0, " missing dev name");
+
+			ifindex = if_nametoindex(argv[arg]);
+			if (!ifindex)
+				error(1, errno, "unknown device %s", argv[arg]);
+
+			rta = (void *)(data + off);
+			rta->rta_type = MPTCP_PM_ADDR_ATTR_IF_IDX;
+			rta->rta_len = RTA_LENGTH(4);
+			memcpy(RTA_DATA(rta), &ifindex, 4);
+			off += NLMSG_ALIGN(rta->rta_len);
+		} else if (!strcmp(argv[arg], "port")) {
+			u_int16_t port;
+
+			if (++arg >= argc)
+				error(1, 0, " missing port value");
+			if (!(flags & MPTCP_PM_ADDR_FLAG_SIGNAL))
+				error(1, 0, " flags must be signal when using port");
+
+			port = atoi(argv[arg]);
+			rta = (void *)(data + off);
+			rta->rta_type = MPTCP_PM_ADDR_ATTR_PORT;
+			rta->rta_len = RTA_LENGTH(2);
+			memcpy(RTA_DATA(rta), &port, 2);
+			off += NLMSG_ALIGN(rta->rta_len);
+		} else
+			error(1, 0, "unknown keyword %s", argv[arg]);
+	}
+	nest->rta_len = off - nest_start;
+
+	do_nl_req(fd, nh, off, 0);
+	return 0;
+}
+
+int del_addr(int fd, int pm_family, int argc, char *argv[])
+{
+	char data[NLMSG_ALIGN(sizeof(struct nlmsghdr)) +
+		  NLMSG_ALIGN(sizeof(struct genlmsghdr)) +
+		  1024];
+	struct rtattr *rta, *nest;
+	struct nlmsghdr *nh;
+	u_int16_t family;
+	int nest_start;
+	u_int8_t id;
+	int off = 0;
+
+	memset(data, 0, sizeof(data));
+	nh = (void *)data;
+	off = init_genl_req(data, pm_family, MPTCP_PM_CMD_DEL_ADDR,
+			    MPTCP_PM_VER);
+
+	/* the only argument is the address id (nonzero) */
+	if (argc != 3 && argc != 4)
+		syntax(argv);
+
+	id = atoi(argv[2]);
+	/* zero id with the IP address */
+	if (!id && argc != 4)
+		syntax(argv);
+
+	nest_start = off;
+	nest = (void *)(data + off);
+	nest->rta_type = NLA_F_NESTED | MPTCP_PM_ATTR_ADDR;
+	nest->rta_len =  RTA_LENGTH(0);
+	off += NLMSG_ALIGN(nest->rta_len);
+
+	/* build a dummy addr with only the ID set */
+	rta = (void *)(data + off);
+	rta->rta_type = MPTCP_PM_ADDR_ATTR_ID;
+	rta->rta_len = RTA_LENGTH(1);
+	memcpy(RTA_DATA(rta), &id, 1);
+	off += NLMSG_ALIGN(rta->rta_len);
+
+	if (!id) {
+		/* addr data */
+		rta = (void *)(data + off);
+		if (inet_pton(AF_INET, argv[3], RTA_DATA(rta))) {
+			family = AF_INET;
+			rta->rta_type = MPTCP_PM_ADDR_ATTR_ADDR4;
+			rta->rta_len = RTA_LENGTH(4);
+		} else if (inet_pton(AF_INET6, argv[3], RTA_DATA(rta))) {
+			family = AF_INET6;
+			rta->rta_type = MPTCP_PM_ADDR_ATTR_ADDR6;
+			rta->rta_len = RTA_LENGTH(16);
+		} else {
+			error(1, errno, "can't parse ip %s", argv[3]);
+		}
+		off += NLMSG_ALIGN(rta->rta_len);
+
+		/* family */
+		rta = (void *)(data + off);
+		rta->rta_type = MPTCP_PM_ADDR_ATTR_FAMILY;
+		rta->rta_len = RTA_LENGTH(2);
+		memcpy(RTA_DATA(rta), &family, 2);
+		off += NLMSG_ALIGN(rta->rta_len);
+	}
+	nest->rta_len = off - nest_start;
+
+	do_nl_req(fd, nh, off, 0);
+	return 0;
+}
+
+static void print_addr(struct rtattr *attrs, int len)
+{
+	uint16_t family = 0;
+	uint16_t port = 0;
+	char str[1024];
+	uint32_t flags;
+	uint8_t id;
+
+	while (RTA_OK(attrs, len)) {
+		if (attrs->rta_type == MPTCP_PM_ADDR_ATTR_FAMILY)
+			memcpy(&family, RTA_DATA(attrs), 2);
+		if (attrs->rta_type == MPTCP_PM_ADDR_ATTR_PORT)
+			memcpy(&port, RTA_DATA(attrs), 2);
+		if (attrs->rta_type == MPTCP_PM_ADDR_ATTR_ADDR4) {
+			if (family != AF_INET)
+				error(1, errno, "wrong IP (v4) for family %d",
+				      family);
+			inet_ntop(AF_INET, RTA_DATA(attrs), str, sizeof(str));
+			printf("%s", str);
+			if (port)
+				printf(" %d", port);
+		}
+		if (attrs->rta_type == MPTCP_PM_ADDR_ATTR_ADDR6) {
+			if (family != AF_INET6)
+				error(1, errno, "wrong IP (v6) for family %d",
+				      family);
+			inet_ntop(AF_INET6, RTA_DATA(attrs), str, sizeof(str));
+			printf("%s", str);
+			if (port)
+				printf(" %d", port);
+		}
+		if (attrs->rta_type == MPTCP_PM_ADDR_ATTR_ID) {
+			memcpy(&id, RTA_DATA(attrs), 1);
+			printf("id %d ", id);
+		}
+		if (attrs->rta_type == MPTCP_PM_ADDR_ATTR_FLAGS) {
+			memcpy(&flags, RTA_DATA(attrs), 4);
+
+			printf("flags ");
+			if (flags & MPTCP_PM_ADDR_FLAG_SIGNAL) {
+				printf("signal");
+				flags &= ~MPTCP_PM_ADDR_FLAG_SIGNAL;
+				if (flags)
+					printf(",");
+			}
+
+			if (flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) {
+				printf("subflow");
+				flags &= ~MPTCP_PM_ADDR_FLAG_SUBFLOW;
+				if (flags)
+					printf(",");
+			}
+
+			if (flags & MPTCP_PM_ADDR_FLAG_BACKUP) {
+				printf("backup");
+				flags &= ~MPTCP_PM_ADDR_FLAG_BACKUP;
+				if (flags)
+					printf(",");
+			}
+
+			if (flags & MPTCP_PM_ADDR_FLAG_FULLMESH) {
+				printf("fullmesh");
+				flags &= ~MPTCP_PM_ADDR_FLAG_FULLMESH;
+				if (flags)
+					printf(",");
+			}
+
+			if (flags & MPTCP_PM_ADDR_FLAG_IMPLICIT) {
+				printf("implicit");
+				flags &= ~MPTCP_PM_ADDR_FLAG_IMPLICIT;
+				if (flags)
+					printf(",");
+			}
+
+			/* bump unknown flags, if any */
+			if (flags)
+				printf("0x%x", flags);
+			printf(" ");
+		}
+		if (attrs->rta_type == MPTCP_PM_ADDR_ATTR_IF_IDX) {
+			char name[IF_NAMESIZE], *ret;
+			int32_t ifindex;
+
+			memcpy(&ifindex, RTA_DATA(attrs), 4);
+			ret = if_indextoname(ifindex, name);
+			if (ret)
+				printf("dev %s ", ret);
+			else
+				printf("dev unknown/%d", ifindex);
+		}
+
+		attrs = RTA_NEXT(attrs, len);
+	}
+	printf("\n");
+}
+
+static void print_addrs(struct nlmsghdr *nh, int pm_family, int total_len)
+{
+	struct rtattr *attrs;
+
+	for (; NLMSG_OK(nh, total_len); nh = NLMSG_NEXT(nh, total_len)) {
+		int len = nh->nlmsg_len;
+
+		if (nh->nlmsg_type == NLMSG_DONE)
+			break;
+		if (nh->nlmsg_type == NLMSG_ERROR)
+			nl_error(nh);
+		if (nh->nlmsg_type != pm_family)
+			continue;
+
+		len -= NLMSG_LENGTH(GENL_HDRLEN);
+		attrs = (struct rtattr *) ((char *) NLMSG_DATA(nh) +
+					   GENL_HDRLEN);
+		while (RTA_OK(attrs, len)) {
+			if (attrs->rta_type ==
+			    (MPTCP_PM_ATTR_ADDR | NLA_F_NESTED))
+				print_addr((void *)RTA_DATA(attrs),
+					   attrs->rta_len);
+			attrs = RTA_NEXT(attrs, len);
+		}
+	}
+}
+
+int get_addr(int fd, int pm_family, int argc, char *argv[])
+{
+	char data[NLMSG_ALIGN(sizeof(struct nlmsghdr)) +
+		  NLMSG_ALIGN(sizeof(struct genlmsghdr)) +
+		  1024];
+	struct rtattr *rta, *nest;
+	struct nlmsghdr *nh;
+	int nest_start;
+	u_int8_t id;
+	int off = 0;
+
+	memset(data, 0, sizeof(data));
+	nh = (void *)data;
+	off = init_genl_req(data, pm_family, MPTCP_PM_CMD_GET_ADDR,
+			    MPTCP_PM_VER);
+
+	/* the only argument is the address id */
+	if (argc != 3)
+		syntax(argv);
+
+	id = atoi(argv[2]);
+
+	nest_start = off;
+	nest = (void *)(data + off);
+	nest->rta_type = NLA_F_NESTED | MPTCP_PM_ATTR_ADDR;
+	nest->rta_len =  RTA_LENGTH(0);
+	off += NLMSG_ALIGN(nest->rta_len);
+
+	/* build a dummy addr with only the ID set */
+	rta = (void *)(data + off);
+	rta->rta_type = MPTCP_PM_ADDR_ATTR_ID;
+	rta->rta_len = RTA_LENGTH(1);
+	memcpy(RTA_DATA(rta), &id, 1);
+	off += NLMSG_ALIGN(rta->rta_len);
+	nest->rta_len = off - nest_start;
+
+	print_addrs(nh, pm_family, do_nl_req(fd, nh, off, sizeof(data)));
+	return 0;
+}
+
+int dump_addrs(int fd, int pm_family, int argc, char *argv[])
+{
+	char data[NLMSG_ALIGN(sizeof(struct nlmsghdr)) +
+		  NLMSG_ALIGN(sizeof(struct genlmsghdr)) +
+		  1024];
+	pid_t pid = getpid();
+	struct nlmsghdr *nh;
+	int off = 0;
+
+	memset(data, 0, sizeof(data));
+	nh = (void *)data;
+	off = init_genl_req(data, pm_family, MPTCP_PM_CMD_GET_ADDR,
+			    MPTCP_PM_VER);
+	nh->nlmsg_flags |= NLM_F_DUMP;
+	nh->nlmsg_seq = 1;
+	nh->nlmsg_pid = pid;
+	nh->nlmsg_len = off;
+
+	print_addrs(nh, pm_family, do_nl_req(fd, nh, off, sizeof(data)));
+	return 0;
+}
+
+int flush_addrs(int fd, int pm_family, int argc, char *argv[])
+{
+	char data[NLMSG_ALIGN(sizeof(struct nlmsghdr)) +
+		  NLMSG_ALIGN(sizeof(struct genlmsghdr)) +
+		  1024];
+	struct nlmsghdr *nh;
+	int off = 0;
+
+	memset(data, 0, sizeof(data));
+	nh = (void *)data;
+	off = init_genl_req(data, pm_family, MPTCP_PM_CMD_FLUSH_ADDRS,
+			    MPTCP_PM_VER);
+
+	do_nl_req(fd, nh, off, 0);
+	return 0;
+}
+
+static void print_limits(struct nlmsghdr *nh, int pm_family, int total_len)
+{
+	struct rtattr *attrs;
+	uint32_t max;
+
+	for (; NLMSG_OK(nh, total_len); nh = NLMSG_NEXT(nh, total_len)) {
+		int len = nh->nlmsg_len;
+
+		if (nh->nlmsg_type == NLMSG_DONE)
+			break;
+		if (nh->nlmsg_type == NLMSG_ERROR)
+			nl_error(nh);
+		if (nh->nlmsg_type != pm_family)
+			continue;
+
+		len -= NLMSG_LENGTH(GENL_HDRLEN);
+		attrs = (struct rtattr *) ((char *) NLMSG_DATA(nh) +
+					   GENL_HDRLEN);
+		while (RTA_OK(attrs, len)) {
+			int type = attrs->rta_type;
+
+			if (type != MPTCP_PM_ATTR_RCV_ADD_ADDRS &&
+			    type != MPTCP_PM_ATTR_SUBFLOWS)
+				goto next;
+
+			memcpy(&max, RTA_DATA(attrs), 4);
+			printf("%s %u\n", type == MPTCP_PM_ATTR_SUBFLOWS ?
+					  "subflows" : "accept", max);
+
+next:
+			attrs = RTA_NEXT(attrs, len);
+		}
+	}
+}
+
+int get_set_limits(int fd, int pm_family, int argc, char *argv[])
+{
+	char data[NLMSG_ALIGN(sizeof(struct nlmsghdr)) +
+		  NLMSG_ALIGN(sizeof(struct genlmsghdr)) +
+		  1024];
+	uint32_t rcv_addr = 0, subflows = 0;
+	int cmd, len = sizeof(data);
+	struct nlmsghdr *nh;
+	int off = 0;
+
+	/* limit */
+	if (argc == 4) {
+		rcv_addr = atoi(argv[2]);
+		subflows = atoi(argv[3]);
+		cmd = MPTCP_PM_CMD_SET_LIMITS;
+	} else {
+		cmd = MPTCP_PM_CMD_GET_LIMITS;
+	}
+
+	memset(data, 0, sizeof(data));
+	nh = (void *)data;
+	off = init_genl_req(data, pm_family, cmd, MPTCP_PM_VER);
+
+	/* limit */
+	if (cmd == MPTCP_PM_CMD_SET_LIMITS) {
+		struct rtattr *rta = (void *)(data + off);
+
+		rta->rta_type = MPTCP_PM_ATTR_RCV_ADD_ADDRS;
+		rta->rta_len = RTA_LENGTH(4);
+		memcpy(RTA_DATA(rta), &rcv_addr, 4);
+		off += NLMSG_ALIGN(rta->rta_len);
+
+		rta = (void *)(data + off);
+		rta->rta_type = MPTCP_PM_ATTR_SUBFLOWS;
+		rta->rta_len = RTA_LENGTH(4);
+		memcpy(RTA_DATA(rta), &subflows, 4);
+		off += NLMSG_ALIGN(rta->rta_len);
+
+		/* do not expect a reply */
+		len = 0;
+	}
+
+	len = do_nl_req(fd, nh, off, len);
+	if (cmd == MPTCP_PM_CMD_GET_LIMITS)
+		print_limits(nh, pm_family, len);
+	return 0;
+}
+
+int add_listener(int argc, char *argv[])
+{
+	struct sockaddr_storage addr;
+	struct sockaddr_in6 *a6;
+	struct sockaddr_in *a4;
+	u_int16_t family;
+	int enable = 1;
+	int sock;
+	int err;
+
+	if (argc < 4)
+		syntax(argv);
+
+	memset(&addr, 0, sizeof(struct sockaddr_storage));
+	a4 = (struct sockaddr_in *)&addr;
+	a6 = (struct sockaddr_in6 *)&addr;
+
+	if (inet_pton(AF_INET, argv[2], &a4->sin_addr)) {
+		family = AF_INET;
+		a4->sin_family = family;
+		a4->sin_port = htons(atoi(argv[3]));
+	} else if (inet_pton(AF_INET6, argv[2], &a6->sin6_addr)) {
+		family = AF_INET6;
+		a6->sin6_family = family;
+		a6->sin6_port = htons(atoi(argv[3]));
+	} else
+		error(1, errno, "can't parse ip %s", argv[2]);
+
+	sock = socket(family, SOCK_STREAM, IPPROTO_MPTCP);
+	if (sock < 0)
+		error(1, errno, "can't create listener sock\n");
+
+	if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &enable, sizeof(enable))) {
+		close(sock);
+		error(1, errno, "can't set SO_REUSEADDR on listener sock\n");
+	}
+
+	err = bind(sock, (struct sockaddr *)&addr,
+		   ((family == AF_INET) ? sizeof(struct sockaddr_in) :
+		    sizeof(struct sockaddr_in6)));
+
+	if (err == 0 && listen(sock, 30) == 0)
+		pause();
+
+	close(sock);
+	return 0;
+}
+
+int set_flags(int fd, int pm_family, int argc, char *argv[])
+{
+	char data[NLMSG_ALIGN(sizeof(struct nlmsghdr)) +
+		  NLMSG_ALIGN(sizeof(struct genlmsghdr)) +
+		  1024];
+	struct rtattr *rta, *nest;
+	struct nlmsghdr *nh;
+	u_int32_t flags = 0;
+	u_int32_t token = 0;
+	u_int16_t rport = 0;
+	u_int16_t family;
+	void *rip = NULL;
+	int nest_start;
+	int use_id = 0;
+	u_int8_t id;
+	int off = 0;
+	int arg = 2;
+
+	memset(data, 0, sizeof(data));
+	nh = (void *)data;
+	off = init_genl_req(data, pm_family, MPTCP_PM_CMD_SET_FLAGS,
+			    MPTCP_PM_VER);
+
+	if (argc < 3)
+		syntax(argv);
+
+	nest_start = off;
+	nest = (void *)(data + off);
+	nest->rta_type = NLA_F_NESTED | MPTCP_PM_ATTR_ADDR;
+	nest->rta_len = RTA_LENGTH(0);
+	off += NLMSG_ALIGN(nest->rta_len);
+
+	if (!strcmp(argv[arg], "id")) {
+		if (++arg >= argc)
+			error(1, 0, " missing id value");
+
+		use_id = 1;
+		id = atoi(argv[arg]);
+		rta = (void *)(data + off);
+		rta->rta_type = MPTCP_PM_ADDR_ATTR_ID;
+		rta->rta_len = RTA_LENGTH(1);
+		memcpy(RTA_DATA(rta), &id, 1);
+		off += NLMSG_ALIGN(rta->rta_len);
+	} else {
+		/* addr data */
+		rta = (void *)(data + off);
+		if (inet_pton(AF_INET, argv[arg], RTA_DATA(rta))) {
+			family = AF_INET;
+			rta->rta_type = MPTCP_PM_ADDR_ATTR_ADDR4;
+			rta->rta_len = RTA_LENGTH(4);
+		} else if (inet_pton(AF_INET6, argv[arg], RTA_DATA(rta))) {
+			family = AF_INET6;
+			rta->rta_type = MPTCP_PM_ADDR_ATTR_ADDR6;
+			rta->rta_len = RTA_LENGTH(16);
+		} else {
+			error(1, errno, "can't parse ip %s", argv[arg]);
+		}
+		off += NLMSG_ALIGN(rta->rta_len);
+
+		/* family */
+		rta = (void *)(data + off);
+		rta->rta_type = MPTCP_PM_ADDR_ATTR_FAMILY;
+		rta->rta_len = RTA_LENGTH(2);
+		memcpy(RTA_DATA(rta), &family, 2);
+		off += NLMSG_ALIGN(rta->rta_len);
+	}
+
+	if (++arg >= argc)
+		error(1, 0, " missing flags keyword");
+
+	for (; arg < argc; arg++) {
+		if (!strcmp(argv[arg], "token")) {
+			if (++arg >= argc)
+				error(1, 0, " missing token value");
+
+			/* token */
+			token = strtoul(argv[arg], NULL, 10);
+		} else if (!strcmp(argv[arg], "flags")) {
+			char *tok, *str;
+
+			/* flags */
+			if (++arg >= argc)
+				error(1, 0, " missing flags value");
+
+			for (str = argv[arg]; (tok = strtok(str, ","));
+			     str = NULL) {
+				if (!strcmp(tok, "backup"))
+					flags |= MPTCP_PM_ADDR_FLAG_BACKUP;
+				else if (!strcmp(tok, "fullmesh"))
+					flags |= MPTCP_PM_ADDR_FLAG_FULLMESH;
+				else if (strcmp(tok, "nobackup") &&
+					 strcmp(tok, "nofullmesh"))
+					error(1, errno,
+					      "unknown flag %s", argv[arg]);
+			}
+
+			rta = (void *)(data + off);
+			rta->rta_type = MPTCP_PM_ADDR_ATTR_FLAGS;
+			rta->rta_len = RTA_LENGTH(4);
+			memcpy(RTA_DATA(rta), &flags, 4);
+			off += NLMSG_ALIGN(rta->rta_len);
+		} else if (!strcmp(argv[arg], "port")) {
+			u_int16_t port;
+
+			if (use_id)
+				error(1, 0, " port can't be used with id");
+
+			if (++arg >= argc)
+				error(1, 0, " missing port value");
+
+			port = atoi(argv[arg]);
+			rta = (void *)(data + off);
+			rta->rta_type = MPTCP_PM_ADDR_ATTR_PORT;
+			rta->rta_len = RTA_LENGTH(2);
+			memcpy(RTA_DATA(rta), &port, 2);
+			off += NLMSG_ALIGN(rta->rta_len);
+		} else if (!strcmp(argv[arg], "rport")) {
+			if (++arg >= argc)
+				error(1, 0, " missing remote port");
+
+			rport = atoi(argv[arg]);
+		} else if (!strcmp(argv[arg], "rip")) {
+			if (++arg >= argc)
+				error(1, 0, " missing remote ip");
+
+			rip = argv[arg];
+		} else {
+			error(1, 0, "unknown keyword %s", argv[arg]);
+		}
+	}
+	nest->rta_len = off - nest_start;
+
+	/* token */
+	if (token) {
+		rta = (void *)(data + off);
+		rta->rta_type = MPTCP_PM_ATTR_TOKEN;
+		rta->rta_len = RTA_LENGTH(4);
+		memcpy(RTA_DATA(rta), &token, 4);
+		off += NLMSG_ALIGN(rta->rta_len);
+	}
+
+	/* remote addr/port */
+	if (rip) {
+		nest_start = off;
+		nest = (void *)(data + off);
+		nest->rta_type = NLA_F_NESTED | MPTCP_PM_ATTR_ADDR_REMOTE;
+		nest->rta_len = RTA_LENGTH(0);
+		off += NLMSG_ALIGN(nest->rta_len);
+
+		/* addr data */
+		rta = (void *)(data + off);
+		if (inet_pton(AF_INET, rip, RTA_DATA(rta))) {
+			family = AF_INET;
+			rta->rta_type = MPTCP_PM_ADDR_ATTR_ADDR4;
+			rta->rta_len = RTA_LENGTH(4);
+		} else if (inet_pton(AF_INET6, rip, RTA_DATA(rta))) {
+			family = AF_INET6;
+			rta->rta_type = MPTCP_PM_ADDR_ATTR_ADDR6;
+			rta->rta_len = RTA_LENGTH(16);
+		} else {
+			error(1, errno, "can't parse ip %s", (char *)rip);
+		}
+		off += NLMSG_ALIGN(rta->rta_len);
+
+		/* family */
+		rta = (void *)(data + off);
+		rta->rta_type = MPTCP_PM_ADDR_ATTR_FAMILY;
+		rta->rta_len = RTA_LENGTH(2);
+		memcpy(RTA_DATA(rta), &family, 2);
+		off += NLMSG_ALIGN(rta->rta_len);
+
+		if (rport) {
+			rta = (void *)(data + off);
+			rta->rta_type = MPTCP_PM_ADDR_ATTR_PORT;
+			rta->rta_len = RTA_LENGTH(2);
+			memcpy(RTA_DATA(rta), &rport, 2);
+			off += NLMSG_ALIGN(rta->rta_len);
+		}
+
+		nest->rta_len = off - nest_start;
+	}
+
+	do_nl_req(fd, nh, off, 0);
+	return 0;
+}
+
+int main(int argc, char *argv[])
+{
+	int events_mcast_grp;
+	int pm_family;
+	int fd;
+
+	if (argc < 2)
+		syntax(argv);
+
+	fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC);
+	if (fd == -1)
+		error(1, errno, "socket netlink");
+
+	resolve_mptcp_pm_netlink(fd, &pm_family, &events_mcast_grp);
+
+	if (!strcmp(argv[1], "add"))
+		return add_addr(fd, pm_family, argc, argv);
+	else if (!strcmp(argv[1], "ann"))
+		return announce_addr(fd, pm_family, argc, argv);
+	else if (!strcmp(argv[1], "rem"))
+		return remove_addr(fd, pm_family, argc, argv);
+	else if (!strcmp(argv[1], "csf"))
+		return csf(fd, pm_family, argc, argv);
+	else if (!strcmp(argv[1], "dsf"))
+		return dsf(fd, pm_family, argc, argv);
+	else if (!strcmp(argv[1], "del"))
+		return del_addr(fd, pm_family, argc, argv);
+	else if (!strcmp(argv[1], "flush"))
+		return flush_addrs(fd, pm_family, argc, argv);
+	else if (!strcmp(argv[1], "get"))
+		return get_addr(fd, pm_family, argc, argv);
+	else if (!strcmp(argv[1], "dump"))
+		return dump_addrs(fd, pm_family, argc, argv);
+	else if (!strcmp(argv[1], "limits"))
+		return get_set_limits(fd, pm_family, argc, argv);
+	else if (!strcmp(argv[1], "set"))
+		return set_flags(fd, pm_family, argc, argv);
+	else if (!strcmp(argv[1], "events"))
+		return capture_events(fd, events_mcast_grp);
+	else if (!strcmp(argv[1], "listen"))
+		return add_listener(argc, argv);
+
+	fprintf(stderr, "unknown sub-command: %s", argv[1]);
+	syntax(argv);
+	return 0;
+}
diff --git a/tools/testing/selftests/net/mptcp/settings b/tools/testing/selftests/net/mptcp/settings
new file mode 100644
index 000000000..79b65bdf0
--- /dev/null
+++ b/tools/testing/selftests/net/mptcp/settings
@@ -0,0 +1 @@
+timeout=1200
diff --git a/tools/testing/selftests/net/mptcp/simult_flows.sh b/tools/testing/selftests/net/mptcp/simult_flows.sh
new file mode 100755
index 000000000..4a417f9d5
--- /dev/null
+++ b/tools/testing/selftests/net/mptcp/simult_flows.sh
@@ -0,0 +1,310 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+. "$(dirname "${0}")/mptcp_lib.sh"
+
+rndh=$(printf %x $sec)-$(mktemp -u XXXXXX)
+ns1="ns1-$rndh"
+ns2="ns2-$rndh"
+ns3="ns3-$rndh"
+capture=false
+ksft_skip=4
+timeout_poll=30
+timeout_test=$((timeout_poll * 2 + 1))
+test_cnt=1
+ret=0
+bail=0
+slack=50
+
+usage() {
+	echo "Usage: $0 [ -b ] [ -c ] [ -d ]"
+	echo -e "\t-b: bail out after first error, otherwise runs al testcases"
+	echo -e "\t-c: capture packets for each test using tcpdump (default: no capture)"
+	echo -e "\t-d: debug this script"
+}
+
+cleanup()
+{
+	rm -f "$cout" "$sout"
+	rm -f "$large" "$small"
+	rm -f "$capout"
+
+	local netns
+	for netns in "$ns1" "$ns2" "$ns3";do
+		ip netns del $netns
+	done
+}
+
+mptcp_lib_check_mptcp
+
+ip -Version > /dev/null 2>&1
+if [ $? -ne 0 ];then
+	echo "SKIP: Could not run test without ip tool"
+	exit $ksft_skip
+fi
+
+#  "$ns1"              ns2                    ns3
+#     ns1eth1    ns2eth1   ns2eth3      ns3eth1
+#            netem
+#     ns1eth2    ns2eth2
+#            netem
+
+setup()
+{
+	large=$(mktemp)
+	small=$(mktemp)
+	sout=$(mktemp)
+	cout=$(mktemp)
+	capout=$(mktemp)
+	size=$((2 * 2048 * 4096))
+
+	dd if=/dev/zero of=$small bs=4096 count=20 >/dev/null 2>&1
+	dd if=/dev/zero of=$large bs=4096 count=$((size / 4096)) >/dev/null 2>&1
+
+	trap cleanup EXIT
+
+	for i in "$ns1" "$ns2" "$ns3";do
+		ip netns add $i || exit $ksft_skip
+		ip -net $i link set lo up
+		ip netns exec $i sysctl -q net.ipv4.conf.all.rp_filter=0
+		ip netns exec $i sysctl -q net.ipv4.conf.default.rp_filter=0
+	done
+
+	ip link add ns1eth1 netns "$ns1" type veth peer name ns2eth1 netns "$ns2"
+	ip link add ns1eth2 netns "$ns1" type veth peer name ns2eth2 netns "$ns2"
+	ip link add ns2eth3 netns "$ns2" type veth peer name ns3eth1 netns "$ns3"
+
+	ip -net "$ns1" addr add 10.0.1.1/24 dev ns1eth1
+	ip -net "$ns1" addr add dead:beef:1::1/64 dev ns1eth1 nodad
+	ip -net "$ns1" link set ns1eth1 up mtu 1500
+	ip -net "$ns1" route add default via 10.0.1.2
+	ip -net "$ns1" route add default via dead:beef:1::2
+
+	ip -net "$ns1" addr add 10.0.2.1/24 dev ns1eth2
+	ip -net "$ns1" addr add dead:beef:2::1/64 dev ns1eth2 nodad
+	ip -net "$ns1" link set ns1eth2 up mtu 1500
+	ip -net "$ns1" route add default via 10.0.2.2 metric 101
+	ip -net "$ns1" route add default via dead:beef:2::2 metric 101
+
+	ip netns exec "$ns1" ./pm_nl_ctl limits 1 1
+	ip netns exec "$ns1" ./pm_nl_ctl add 10.0.2.1 dev ns1eth2 flags subflow
+
+	ip -net "$ns2" addr add 10.0.1.2/24 dev ns2eth1
+	ip -net "$ns2" addr add dead:beef:1::2/64 dev ns2eth1 nodad
+	ip -net "$ns2" link set ns2eth1 up mtu 1500
+
+	ip -net "$ns2" addr add 10.0.2.2/24 dev ns2eth2
+	ip -net "$ns2" addr add dead:beef:2::2/64 dev ns2eth2 nodad
+	ip -net "$ns2" link set ns2eth2 up mtu 1500
+
+	ip -net "$ns2" addr add 10.0.3.2/24 dev ns2eth3
+	ip -net "$ns2" addr add dead:beef:3::2/64 dev ns2eth3 nodad
+	ip -net "$ns2" link set ns2eth3 up mtu 1500
+	ip netns exec "$ns2" sysctl -q net.ipv4.ip_forward=1
+	ip netns exec "$ns2" sysctl -q net.ipv6.conf.all.forwarding=1
+
+	ip -net "$ns3" addr add 10.0.3.3/24 dev ns3eth1
+	ip -net "$ns3" addr add dead:beef:3::3/64 dev ns3eth1 nodad
+	ip -net "$ns3" link set ns3eth1 up mtu 1500
+	ip -net "$ns3" route add default via 10.0.3.2
+	ip -net "$ns3" route add default via dead:beef:3::2
+
+	ip netns exec "$ns3" ./pm_nl_ctl limits 1 1
+
+	# debug build can slow down measurably the test program
+	# we use quite tight time limit on the run-time, to ensure
+	# maximum B/W usage.
+	# Use kmemleak/lockdep/kasan/prove_locking presence as a rough
+	# estimate for this being a debug kernel and increase the
+	# maximum run-time accordingly. Observed run times for CI builds
+	# running selftests, including kbuild, were used to determine the
+	# amount of time to add.
+	grep -q ' kmemleak_init$\| lockdep_init$\| kasan_init$\| prove_locking$' /proc/kallsyms && slack=$((slack+550))
+}
+
+# $1: ns, $2: port
+wait_local_port_listen()
+{
+	local listener_ns="${1}"
+	local port="${2}"
+
+	local port_hex i
+
+	port_hex="$(printf "%04X" "${port}")"
+	for i in $(seq 10); do
+		ip netns exec "${listener_ns}" cat /proc/net/tcp* | \
+			awk "BEGIN {rc=1} {if (\$2 ~ /:${port_hex}\$/ && \$4 ~ /0A/) {rc=0; exit}} END {exit rc}" &&
+			break
+		sleep 0.1
+	done
+}
+
+do_transfer()
+{
+	local cin=$1
+	local sin=$2
+	local max_time=$3
+	local port
+	port=$((10000+$test_cnt))
+	test_cnt=$((test_cnt+1))
+
+	:> "$cout"
+	:> "$sout"
+	:> "$capout"
+
+	local addr_port
+	addr_port=$(printf "%s:%d" ${connect_addr} ${port})
+
+	if $capture; then
+		local capuser
+		if [ -z $SUDO_USER ] ; then
+			capuser=""
+		else
+			capuser="-Z $SUDO_USER"
+		fi
+
+		local capfile="${rndh}-${port}"
+		local capopt="-i any -s 65535 -B 32768 ${capuser}"
+
+		ip netns exec ${ns3}  tcpdump ${capopt} -w "${capfile}-listener.pcap"  >> "${capout}" 2>&1 &
+		local cappid_listener=$!
+
+		ip netns exec ${ns1} tcpdump ${capopt} -w "${capfile}-connector.pcap" >> "${capout}" 2>&1 &
+		local cappid_connector=$!
+
+		sleep 1
+	fi
+
+	timeout ${timeout_test} \
+		ip netns exec ${ns3} \
+			./mptcp_connect -jt ${timeout_poll} -l -p $port -T $time \
+				0.0.0.0 < "$sin" > "$sout" &
+	local spid=$!
+
+	wait_local_port_listen "${ns3}" "${port}"
+
+	timeout ${timeout_test} \
+		ip netns exec ${ns1} \
+			./mptcp_connect -jt ${timeout_poll} -p $port -T $time \
+				10.0.3.3 < "$cin" > "$cout" &
+	local cpid=$!
+
+	wait $cpid
+	local retc=$?
+	wait $spid
+	local rets=$?
+
+	if $capture; then
+		sleep 1
+		kill ${cappid_listener}
+		kill ${cappid_connector}
+	fi
+
+	cmp $sin $cout > /dev/null 2>&1
+	local cmps=$?
+	cmp $cin $sout > /dev/null 2>&1
+	local cmpc=$?
+
+	printf "%-16s" " max $max_time "
+	if [ $retc -eq 0 ] && [ $rets -eq 0 ] && \
+	   [ $cmpc -eq 0 ] && [ $cmps -eq 0 ]; then
+		echo "[ OK ]"
+		cat "$capout"
+		return 0
+	fi
+
+	echo " [ fail ]"
+	echo "client exit code $retc, server $rets" 1>&2
+	echo -e "\nnetns ${ns3} socket stat for $port:" 1>&2
+	ip netns exec ${ns3} ss -nita 1>&2 -o "sport = :$port"
+	echo -e "\nnetns ${ns1} socket stat for $port:" 1>&2
+	ip netns exec ${ns1} ss -nita 1>&2 -o "dport = :$port"
+	ls -l $sin $cout
+	ls -l $cin $sout
+
+	cat "$capout"
+	return 1
+}
+
+run_test()
+{
+	local rate1=$1
+	local rate2=$2
+	local delay1=$3
+	local delay2=$4
+	local lret
+	local dev
+	shift 4
+	local msg=$*
+
+	[ $delay1 -gt 0 ] && delay1="delay $delay1" || delay1=""
+	[ $delay2 -gt 0 ] && delay2="delay $delay2" || delay2=""
+
+	for dev in ns1eth1 ns1eth2; do
+		tc -n $ns1 qdisc del dev $dev root >/dev/null 2>&1
+	done
+	for dev in ns2eth1 ns2eth2; do
+		tc -n $ns2 qdisc del dev $dev root >/dev/null 2>&1
+	done
+	tc -n $ns1 qdisc add dev ns1eth1 root netem rate ${rate1}mbit $delay1
+	tc -n $ns1 qdisc add dev ns1eth2 root netem rate ${rate2}mbit $delay2
+	tc -n $ns2 qdisc add dev ns2eth1 root netem rate ${rate1}mbit $delay1
+	tc -n $ns2 qdisc add dev ns2eth2 root netem rate ${rate2}mbit $delay2
+
+	# time is measured in ms, account for transfer size, aggregated link speed
+	# and header overhead (10%)
+	#              ms    byte -> bit   10%        mbit      -> kbit -> bit  10%
+	local time=$((1000 * size  *  8  * 10 / ((rate1 + rate2) * 1000 * 1000 * 9) ))
+
+	# mptcp_connect will do some sleeps to allow the mp_join handshake
+	# completion (see mptcp_connect): 200ms on each side, add some slack
+	time=$((time + 400 + slack))
+
+	printf "%-60s" "$msg"
+	do_transfer $small $large $time
+	lret=$?
+	if [ $lret -ne 0 ]; then
+		ret=$lret
+		[ $bail -eq 0 ] || exit $ret
+	fi
+
+	printf "%-60s" "$msg - reverse direction"
+	do_transfer $large $small $time
+	lret=$?
+	if [ $lret -ne 0 ]; then
+		ret=$lret
+		[ $bail -eq 0 ] || exit $ret
+	fi
+}
+
+while getopts "bcdh" option;do
+	case "$option" in
+	"h")
+		usage $0
+		exit 0
+		;;
+	"b")
+		bail=1
+		;;
+	"c")
+		capture=true
+		;;
+	"d")
+		set -x
+		;;
+	"?")
+		usage $0
+		exit 1
+		;;
+	esac
+done
+
+setup
+run_test 10 10 0 0 "balanced bwidth"
+run_test 10 10 1 50 "balanced bwidth with unbalanced delay"
+
+# we still need some additional infrastructure to pass the following test-cases
+run_test 30 10 0 0 "unbalanced bwidth"
+run_test 30 10 1 50 "unbalanced bwidth with unbalanced delay"
+run_test 30 10 50 1 "unbalanced bwidth with opposed, unbalanced delay"
+exit $ret
diff --git a/tools/testing/selftests/net/mptcp/userspace_pm.sh b/tools/testing/selftests/net/mptcp/userspace_pm.sh
new file mode 100755
index 000000000..cb6c28d40
--- /dev/null
+++ b/tools/testing/selftests/net/mptcp/userspace_pm.sh
@@ -0,0 +1,886 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+. "$(dirname "${0}")/mptcp_lib.sh"
+
+mptcp_lib_check_mptcp
+
+if ! mptcp_lib_has_file '/proc/sys/net/mptcp/pm_type'; then
+	echo "userspace pm tests are not supported by the kernel: SKIP"
+	exit ${KSFT_SKIP}
+fi
+
+ip -Version > /dev/null 2>&1
+if [ $? -ne 0 ];then
+	echo "SKIP: Cannot not run test without ip tool"
+	exit ${KSFT_SKIP}
+fi
+
+ANNOUNCED=6        # MPTCP_EVENT_ANNOUNCED
+REMOVED=7          # MPTCP_EVENT_REMOVED
+SUB_ESTABLISHED=10 # MPTCP_EVENT_SUB_ESTABLISHED
+SUB_CLOSED=11      # MPTCP_EVENT_SUB_CLOSED
+
+AF_INET=2
+AF_INET6=10
+
+evts_pid=0
+client4_pid=0
+server4_pid=0
+client6_pid=0
+server6_pid=0
+client4_token=""
+server4_token=""
+client6_token=""
+server6_token=""
+client4_port=0;
+client6_port=0;
+app4_port=50002
+new4_port=50003
+app6_port=50004
+client_addr_id=${RANDOM:0:2}
+server_addr_id=${RANDOM:0:2}
+
+sec=$(date +%s)
+rndh=$(stdbuf -o0 -e0 printf %x "$sec")-$(mktemp -u XXXXXX)
+ns1="ns1-$rndh"
+ns2="ns2-$rndh"
+
+kill_wait()
+{
+	kill $1 > /dev/null 2>&1
+	wait $1 2>/dev/null
+}
+
+cleanup()
+{
+	echo "cleanup"
+
+	rm -rf $file
+
+	# Terminate the MPTCP connection and related processes
+	if [ $client4_pid -ne 0 ]; then
+		kill -SIGUSR1 $client4_pid > /dev/null 2>&1
+	fi
+	if [ $server4_pid -ne 0 ]; then
+		kill_wait $server4_pid
+	fi
+	if [ $client6_pid -ne 0 ]; then
+		kill -SIGUSR1 $client6_pid > /dev/null 2>&1
+	fi
+	if [ $server6_pid -ne 0 ]; then
+		kill_wait $server6_pid
+	fi
+	if [ $evts_pid -ne 0 ]; then
+		kill_wait $evts_pid
+	fi
+	local netns
+	for netns in "$ns1" "$ns2" ;do
+		ip netns del "$netns"
+	done
+}
+
+trap cleanup EXIT
+
+# Create and configure network namespaces for testing
+for i in "$ns1" "$ns2" ;do
+	ip netns add "$i" || exit 1
+	ip -net "$i" link set lo up
+	ip netns exec "$i" sysctl -q net.mptcp.enabled=1
+	ip netns exec "$i" sysctl -q net.mptcp.pm_type=1
+done
+
+#  "$ns1"              ns2
+#     ns1eth2    ns2eth1
+
+ip link add ns1eth2 netns "$ns1" type veth peer name ns2eth1 netns "$ns2"
+
+# Add IPv4/v6 addresses to the namespaces
+ip -net "$ns1" addr add 10.0.1.1/24 dev ns1eth2
+ip -net "$ns1" addr add 10.0.2.1/24 dev ns1eth2
+ip -net "$ns1" addr add dead:beef:1::1/64 dev ns1eth2 nodad
+ip -net "$ns1" addr add dead:beef:2::1/64 dev ns1eth2 nodad
+ip -net "$ns1" link set ns1eth2 up
+
+ip -net "$ns2" addr add 10.0.1.2/24 dev ns2eth1
+ip -net "$ns2" addr add 10.0.2.2/24 dev ns2eth1
+ip -net "$ns2" addr add dead:beef:1::2/64 dev ns2eth1 nodad
+ip -net "$ns2" addr add dead:beef:2::2/64 dev ns2eth1 nodad
+ip -net "$ns2" link set ns2eth1 up
+
+stdbuf -o0 -e0 printf "Created network namespaces ns1, ns2         \t\t\t[OK]\n"
+
+make_file()
+{
+	# Store a chunk of data in a file to transmit over an MPTCP connection
+	local name=$1
+	local ksize=1
+
+	dd if=/dev/urandom of="$name" bs=2 count=$ksize 2> /dev/null
+	echo -e "\nMPTCP_TEST_FILE_END_MARKER" >> "$name"
+}
+
+make_connection()
+{
+	local file
+	file=$(mktemp)
+	make_file "$file" "client"
+
+	local is_v6=$1
+	local app_port=$app4_port
+	local connect_addr="10.0.1.1"
+	local listen_addr="0.0.0.0"
+	if [ "$is_v6" = "v6" ]
+	then
+		connect_addr="dead:beef:1::1"
+		listen_addr="::"
+		app_port=$app6_port
+	else
+		is_v6="v4"
+	fi
+
+	# Capture netlink events over the two network namespaces running
+	# the MPTCP client and server
+	local client_evts
+	client_evts=$(mktemp)
+	:>"$client_evts"
+	ip netns exec "$ns2" ./pm_nl_ctl events >> "$client_evts" 2>&1 &
+	local client_evts_pid=$!
+	local server_evts
+	server_evts=$(mktemp)
+	:>"$server_evts"
+	ip netns exec "$ns1" ./pm_nl_ctl events >> "$server_evts" 2>&1 &
+	local server_evts_pid=$!
+	sleep 0.5
+
+	# Run the server
+	ip netns exec "$ns1" \
+	   ./mptcp_connect -s MPTCP -w 300 -p $app_port -l $listen_addr > /dev/null 2>&1 &
+	local server_pid=$!
+	sleep 0.5
+
+	# Run the client, transfer $file and stay connected to the server
+	# to conduct tests
+	ip netns exec "$ns2" \
+	   ./mptcp_connect -s MPTCP -w 300 -m sendfile -p $app_port $connect_addr\
+	   2>&1 > /dev/null < "$file" &
+	local client_pid=$!
+	sleep 1
+
+	# Capture client/server attributes from MPTCP connection netlink events
+	kill_wait $client_evts_pid
+
+	local client_token
+	local client_port
+	local client_serverside
+	local server_token
+	local server_serverside
+
+	client_token=$(sed --unbuffered -n 's/.*\(token:\)\([[:digit:]]*\).*$/\2/p;q' "$client_evts")
+	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" "$file"
+
+	if [ "$client_token" != "" ] && [ "$server_token" != "" ] && [ "$client_serverside" = 0 ] &&
+		   [ "$server_serverside" = 1 ]
+	then
+		stdbuf -o0 -e0 printf "Established IP%s MPTCP Connection ns2 => ns1    \t\t[OK]\n" $is_v6
+	else
+		exit 1
+	fi
+
+	if [ "$is_v6" = "v6" ]
+	then
+		client6_token=$client_token
+		server6_token=$server_token
+		client6_port=$client_port
+		client6_pid=$client_pid
+		server6_pid=$server_pid
+	else
+		client4_token=$client_token
+		server4_token=$server_token
+		client4_port=$client_port
+		client4_pid=$client_pid
+		server4_pid=$server_pid
+	fi
+}
+
+verify_announce_event()
+{
+	local evt=$1
+	local e_type=$2
+	local e_token=$3
+	local e_addr=$4
+	local e_id=$5
+	local e_dport=$6
+	local e_af=$7
+	local type
+	local token
+	local addr
+	local dport
+	local id
+
+	type=$(sed --unbuffered -n 's/.*\(type:\)\([[:digit:]]*\).*$/\2/p;q' "$evt")
+	token=$(sed --unbuffered -n 's/.*\(token:\)\([[:digit:]]*\).*$/\2/p;q' "$evt")
+	if [ "$e_af" = "v6" ]
+	then
+		addr=$(sed --unbuffered -n 's/.*\(daddr6:\)\([0-9a-f:.]*\).*$/\2/p;q' "$evt")
+	else
+		addr=$(sed --unbuffered -n 's/.*\(daddr4:\)\([0-9.]*\).*$/\2/p;q' "$evt")
+	fi
+	dport=$(sed --unbuffered -n 's/.*\(dport:\)\([[:digit:]]*\).*$/\2/p;q' "$evt")
+	id=$(sed --unbuffered -n 's/.*\(rem_id:\)\([[:digit:]]*\).*$/\2/p;q' "$evt")
+	if [ "$type" = "$e_type" ] && [ "$token" = "$e_token" ] &&
+		   [ "$addr" = "$e_addr" ] && [ "$dport" = "$e_dport" ] &&
+		   [ "$id" = "$e_id" ]
+	then
+		stdbuf -o0 -e0 printf "[OK]\n"
+		return 0
+	fi
+	stdbuf -o0 -e0 printf "[FAIL]\n"
+	exit 1
+}
+
+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=$!
+	sleep 0.5
+
+	# ADD_ADDR using an invalid token should result in no action
+	local invalid_token=$(( client4_token - 1))
+	ip netns exec "$ns2" ./pm_nl_ctl ann 10.0.2.2 token $invalid_token id\
+	   $client_addr_id dev ns2eth1 > /dev/null 2>&1
+
+	local type
+	type=$(sed --unbuffered -n 's/.*\(type:\)\([[:digit:]]*\).*$/\2/p;q' "$evts")
+	stdbuf -o0 -e0 printf "ADD_ADDR 10.0.2.2 (ns2) => ns1, invalid token    \t\t"
+	if [ "$type" = "" ]
+	then
+		stdbuf -o0 -e0 printf "[OK]\n"
+	else
+		stdbuf -o0 -e0 printf "[FAIL]\n"
+		exit 1
+	fi
+
+	# ADD_ADDR from the client to server machine reusing the subflow port
+	:>"$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" "$client_addr_id"\
+			      "$client4_port"
+
+	# ADD_ADDR6 from the client to server machine reusing the subflow port
+	:>"$evts"
+	ip netns exec "$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"\
+			      "$client_addr_id" "$client6_port" "v6"
+
+	# ADD_ADDR from the client to server machine using a new port
+	:>"$evts"
+	client_addr_id=$((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"\
+			      "$client_addr_id" "$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=$!
+	sleep 0.5
+
+	# ADD_ADDR from the server to client machine reusing the subflow port
+	ip netns exec "$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"\
+			      "$server_addr_id" "$app4_port"
+
+	# ADD_ADDR6 from the server to client machine reusing the subflow port
+	:>"$evts"
+	ip netns exec "$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"\
+			      "$server_addr_id" "$app6_port" "v6"
+
+	# ADD_ADDR from the server to client machine using a new port
+	:>"$evts"
+	server_addr_id=$((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"\
+			      "$server_addr_id" "$new4_port"
+
+	kill_wait $evts_pid
+	rm -f "$evts"
+}
+
+verify_remove_event()
+{
+	local evt=$1
+	local e_type=$2
+	local e_token=$3
+	local e_id=$4
+	local type
+	local token
+	local id
+
+	type=$(sed --unbuffered -n 's/.*\(type:\)\([[:digit:]]*\).*$/\2/p;q' "$evt")
+	token=$(sed --unbuffered -n 's/.*\(token:\)\([[:digit:]]*\).*$/\2/p;q' "$evt")
+	id=$(sed --unbuffered -n 's/.*\(rem_id:\)\([[:digit:]]*\).*$/\2/p;q' "$evt")
+	if [ "$type" = "$e_type" ] && [ "$token" = "$e_token" ] &&
+		   [ "$id" = "$e_id" ]
+	then
+		stdbuf -o0 -e0 printf "[OK]\n"
+		return 0
+	fi
+	stdbuf -o0 -e0 printf "[FAIL]\n"
+	exit 1
+}
+
+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=$!
+	sleep 0.5
+
+	# RM_ADDR using an invalid token should result in no action
+	local invalid_token=$(( client4_token - 1 ))
+	ip netns exec "$ns2" ./pm_nl_ctl rem token $invalid_token id\
+	   $client_addr_id > /dev/null 2>&1
+	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")
+	if [ "$type" = "" ]
+	then
+		stdbuf -o0 -e0 printf "[OK]\n"
+	else
+		stdbuf -o0 -e0 printf "[FAIL]\n"
+		exit 1
+	fi
+
+	# RM_ADDR using an invalid addr id should result in no action
+	local invalid_id=$(( client_addr_id + 1 ))
+	ip netns exec "$ns2" ./pm_nl_ctl rem token "$client4_token" id\
+	   $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")
+	if [ "$type" = "" ]
+	then
+		stdbuf -o0 -e0 printf "[OK]\n"
+	else
+		stdbuf -o0 -e0 printf "[FAIL]\n"
+		exit 1
+	fi
+
+	# RM_ADDR from the client to server machine
+	:>"$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" "$client_addr_id"
+
+	# RM_ADDR from the client to server machine
+	:>"$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" "$client_addr_id"
+
+	# RM_ADDR6 from the client to server machine
+	:>"$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 $evts_pid
+
+	# Capture events on the network namespace running the client
+	:>"$evts"
+	ip netns exec "$ns2" ./pm_nl_ctl events >> "$evts" 2>&1 &
+	evts_pid=$!
+	sleep 0.5
+
+	# RM_ADDR from the server to client machine
+	ip netns exec "$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" "$server_addr_id"
+
+	# RM_ADDR from the server to client machine
+	:>"$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" "$server_addr_id"
+
+	# RM_ADDR6 from the server to client machine
+	:>"$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_subflow_events()
+{
+	local evt=$1
+	local e_type=$2
+	local e_token=$3
+	local e_family=$4
+	local e_saddr=$5
+	local e_daddr=$6
+	local e_dport=$7
+	local e_locid=$8
+	local e_remid=$9
+	shift 2
+	local e_from=$8
+	local e_to=$9
+	local type
+	local token
+	local family
+	local saddr
+	local daddr
+	local dport
+	local locid
+	local remid
+
+	if [ "$e_type" = "$SUB_ESTABLISHED" ]
+	then
+		if [ "$e_family" = "$AF_INET6" ]
+		then
+			stdbuf -o0 -e0 printf "CREATE_SUBFLOW6 %s (%s) => %s (%s)    "\
+			       "$e_saddr" "$e_from" "$e_daddr" "$e_to"
+		else
+			stdbuf -o0 -e0 printf "CREATE_SUBFLOW %s (%s) => %s (%s)         \t"\
+			       "$e_saddr" "$e_from" "$e_daddr" "$e_to"
+		fi
+	else
+		if [ "$e_family" = "$AF_INET6" ]
+		then
+			stdbuf -o0 -e0 printf "DESTROY_SUBFLOW6 %s (%s) => %s (%s)   "\
+			       "$e_saddr" "$e_from" "$e_daddr" "$e_to"
+		else
+			stdbuf -o0 -e0 printf "DESTROY_SUBFLOW %s (%s) => %s (%s)         \t"\
+			       "$e_saddr" "$e_from" "$e_daddr" "$e_to"
+		fi
+	fi
+
+	type=$(sed --unbuffered -n 's/.*\(type:\)\([[:digit:]]*\).*$/\2/p;q' "$evt")
+	token=$(sed --unbuffered -n 's/.*\(token:\)\([[:digit:]]*\).*$/\2/p;q' "$evt")
+	family=$(sed --unbuffered -n 's/.*\(family:\)\([[:digit:]]*\).*$/\2/p;q' "$evt")
+	dport=$(sed --unbuffered -n 's/.*\(dport:\)\([[:digit:]]*\).*$/\2/p;q' "$evt")
+	locid=$(sed --unbuffered -n 's/.*\(loc_id:\)\([[:digit:]]*\).*$/\2/p;q' "$evt")
+	remid=$(sed --unbuffered -n 's/.*\(rem_id:\)\([[:digit:]]*\).*$/\2/p;q' "$evt")
+	if [ "$family" = "$AF_INET6" ]
+	then
+		saddr=$(sed --unbuffered -n 's/.*\(saddr6:\)\([0-9a-f:.]*\).*$/\2/p;q' "$evt")
+		daddr=$(sed --unbuffered -n 's/.*\(daddr6:\)\([0-9a-f:.]*\).*$/\2/p;q' "$evt")
+	else
+		saddr=$(sed --unbuffered -n 's/.*\(saddr4:\)\([0-9.]*\).*$/\2/p;q' "$evt")
+		daddr=$(sed --unbuffered -n 's/.*\(daddr4:\)\([0-9.]*\).*$/\2/p;q' "$evt")
+	fi
+
+	if [ "$type" = "$e_type" ] && [ "$token" = "$e_token" ] &&
+		   [ "$daddr" = "$e_daddr" ] && [ "$e_dport" = "$dport" ] &&
+		   [ "$family" = "$e_family" ] && [ "$saddr" = "$e_saddr" ] &&
+		   [ "$e_locid" = "$locid" ] && [ "$e_remid" = "$remid" ]
+	then
+		stdbuf -o0 -e0 printf "[OK]\n"
+		return 0
+	fi
+	stdbuf -o0 -e0 printf "[FAIL]\n"
+	exit 1
+}
+
+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=$!
+	sleep 0.5
+
+	# Attempt to add a listener at 10.0.2.2:<subflow-port>
+	ip netns exec "$ns2" ./pm_nl_ctl listen 10.0.2.2\
+	   "$client4_port" > /dev/null 2>&1 &
+	local listener_pid=$!
+
+	# 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\
+	   $client_addr_id > /dev/null 2>&1
+	sleep 0.5
+
+	# CREATE_SUBFLOW from server to client machine
+	:>"$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" "$AF_INET" "10.0.2.1"\
+			      "10.0.2.2" "$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")
+
+	# DESTROY_SUBFLOW from server to client machine
+	:>"$evts"
+	ip netns exec "$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" "$AF_INET" "10.0.2.1"\
+			      "10.0.2.2" "$client4_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
+	sleep 0.5
+
+	# Attempt to add a listener at dead:beef:2::2:<subflow-port>
+	ip netns exec "$ns2" ./pm_nl_ctl listen dead:beef:2::2\
+	   "$client6_port" > /dev/null 2>&1 &
+	listener_pid=$!
+
+	# ADD_ADDR6 from client to server machine reusing the subflow port
+	:>"$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"
+	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" "$AF_INET6"\
+			      "dead:beef:2::1" "dead:beef:2::2" "$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")
+
+	# DESTROY_SUBFLOW6 from server to client machine
+	:>"$evts"
+	ip netns exec "$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" "$AF_INET6"\
+			      "dead:beef:2::1" "dead:beef:2::2" "$client6_port" "23"\
+			      "$client_addr_id" "ns1" "ns2"
+
+	# RM_ADDR from client to server machine
+	ip netns exec "$ns2" ./pm_nl_ctl rem id $client_addr_id token\
+	   "$client6_token" > /dev/null 2>&1
+	sleep 0.5
+
+	# Attempt to add a listener at 10.0.2.2:<new-port>
+	ip netns exec "$ns2" ./pm_nl_ctl listen 10.0.2.2\
+	   $new4_port > /dev/null 2>&1 &
+	listener_pid=$!
+
+	# ADD_ADDR from client to server machine using a new port
+	:>"$evts"
+	ip netns exec "$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"
+	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"\
+			      "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")
+
+	# DESTROY_SUBFLOW from server to client machine
+	:>"$evts"
+	ip netns exec "$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"\
+			      "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=$!
+	sleep 0.5
+
+	# Attempt to add a listener at 10.0.2.1:<subflow-port>
+	ip netns exec "$ns1" ./pm_nl_ctl listen 10.0.2.1\
+	   $app4_port > /dev/null 2>&1 &
+	listener_pid=$!
+
+	# ADD_ADDR from server to client machine reusing the subflow port
+	ip netns exec "$ns1" ./pm_nl_ctl ann 10.0.2.1 token "$server4_token" id\
+	   $server_addr_id > /dev/null 2>&1
+	sleep 0.5
+
+	# CREATE_SUBFLOW from client to server machine
+	:>"$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"\
+			      "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")
+
+	# DESTROY_SUBFLOW from client to server machine
+	:>"$evts"
+	ip netns exec "$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"\
+			      "10.0.2.1" "$app4_port" "23" "$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
+	sleep 0.5
+
+	# Attempt to add a listener at dead:beef:2::1:<subflow-port>
+	ip netns exec "$ns1" ./pm_nl_ctl listen dead:beef:2::1\
+	   $app6_port > /dev/null 2>&1 &
+	listener_pid=$!
+
+	# ADD_ADDR6 from server to client machine reusing the subflow port
+	:>"$evts"
+	ip netns exec "$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"
+	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" "$client6_token"\
+			      "$AF_INET6" "dead:beef:2::2"\
+			      "dead:beef:2::1" "$app6_port" "23"\
+			      "$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")
+
+	# DESTROY_SUBFLOW6 from client to server machine
+	:>"$evts"
+	ip netns exec "$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"\
+			      "dead:beef:2::1" "$app6_port" "23" "$server_addr_id" "ns2" "ns1"
+
+	# RM_ADDR6 from server to client machine
+	ip netns exec "$ns1" ./pm_nl_ctl rem id $server_addr_id token\
+	   "$server6_token" > /dev/null 2>&1
+	sleep 0.5
+
+	# Attempt to add a listener at 10.0.2.1:<new-port>
+	ip netns exec "$ns1" ./pm_nl_ctl listen 10.0.2.1\
+	   $new4_port > /dev/null 2>&1 &
+	listener_pid=$!
+
+	# ADD_ADDR from server to client machine using a new port
+	:>"$evts"
+	ip netns exec "$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"
+	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"\
+			      "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")
+
+	# DESTROY_SUBFLOW from client to server machine
+	:>"$evts"
+	ip netns exec "$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"\
+			      "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_subflows_v4_v6_mix()
+{
+	local client_evts
+	client_evts=$(mktemp)
+	# Capture events on the network namespace running the client
+	:>"$client_evts"
+	ip netns exec "$ns2" ./pm_nl_ctl events >> "$client_evts" 2>&1 &
+	evts_pid=$!
+	sleep 0.5
+
+	# Attempt to add a listener at 10.0.2.1:<subflow-port>
+	ip netns exec "$ns1" ./pm_nl_ctl listen 10.0.2.1\
+	   $app6_port > /dev/null 2>&1 &
+	local listener_pid=$!
+
+	# ADD_ADDR4 from server to client machine reusing the subflow port on
+	# the established v6 connection
+	:>"$client_evts"
+	ip netns exec "$ns1" ./pm_nl_ctl ann 10.0.2.1 token "$server6_token" id\
+	   $server_addr_id dev ns1eth2 > /dev/null 2>&1
+	stdbuf -o0 -e0 printf "ADD_ADDR4 id:%d 10.0.2.1 (ns1) => ns2, reuse port\t\t" $server_addr_id
+	sleep 0.5
+	verify_announce_event "$client_evts" "$ANNOUNCED" "$client6_token" "10.0.2.1"\
+			      "$server_addr_id" "$app6_port"
+
+	# CREATE_SUBFLOW from client to server machine
+	:>"$client_evts"
+	ip netns exec "$ns2" ./pm_nl_ctl csf lip 10.0.2.2 lid 23 rip 10.0.2.1 rport\
+	   $app6_port token "$client6_token" > /dev/null 2>&1
+	sleep 0.5
+	verify_subflow_events "$client_evts" "$SUB_ESTABLISHED" "$client6_token"\
+			      "$AF_INET" "10.0.2.2" "10.0.2.1" "$app6_port" "23"\
+			      "$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/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q' "$client_evts")
+
+	# DESTROY_SUBFLOW from client to server machine
+	:>"$client_evts"
+	ip netns exec "$ns2" ./pm_nl_ctl dsf lip 10.0.2.2 lport "$sport" rip 10.0.2.1 rport\
+	   $app6_port token "$client6_token" > /dev/null 2>&1
+	sleep 0.5
+	verify_subflow_events "$client_evts" "$SUB_CLOSED" "$client6_token" \
+			      "$AF_INET" "10.0.2.2" "10.0.2.1" "$app6_port" "23"\
+			      "$server_addr_id" "ns2" "ns1"
+
+	# RM_ADDR from server to client machine
+	ip netns exec "$ns1" ./pm_nl_ctl rem id $server_addr_id token\
+	   "$server6_token" > /dev/null 2>&1
+	sleep 0.5
+
+	kill_wait $evts_pid
+	rm -f "$client_evts"
+}
+
+test_prio()
+{
+	local count
+
+	# Send MP_PRIO signal from client to server machine
+	ip netns exec "$ns2" ./pm_nl_ctl set 10.0.1.2 port "$client4_port" flags backup token "$client4_token" rip 10.0.1.1 rport "$app4_port"
+	sleep 0.5
+
+	# Check TX
+	stdbuf -o0 -e0 printf "MP_PRIO TX                                                 \t"
+	count=$(ip netns exec "$ns2" nstat -as | grep MPTcpExtMPPrioTx | awk '{print $2}')
+	[ -z "$count" ] && count=0
+	if [ $count != 1 ]; then
+		stdbuf -o0 -e0 printf "[FAIL]\n"
+		exit 1
+	else
+		stdbuf -o0 -e0 printf "[OK]\n"
+	fi
+
+	# Check RX
+	stdbuf -o0 -e0 printf "MP_PRIO RX                                                 \t"
+	count=$(ip netns exec "$ns1" nstat -as | grep MPTcpExtMPPrioRx | awk '{print $2}')
+	[ -z "$count" ] && count=0
+	if [ $count != 1 ]; then
+		stdbuf -o0 -e0 printf "[FAIL]\n"
+		exit 1
+	else
+		stdbuf -o0 -e0 printf "[OK]\n"
+	fi
+}
+
+make_connection
+make_connection "v6"
+test_announce
+test_remove
+test_subflows
+test_subflows_v4_v6_mix
+test_prio
+
+exit 0
-- 
cgit v1.2.3