This patch added the self tests for MP_FASTCLOSE. Added a new argment
fastclose for the function do_transfer(). Passed the extra argments '-I 2'
and '-I 3' to the mptcp_connect commands to disconnect the connections to
trigger the MP_FASTCLOSE sending and receiving. Used chk_fclose_nr to check
the MP_FASTCLOSE mibs and used chk_rst_nr to check the MP_RST mibs.

The output looks like this:

001 fastclose test 1              syn[ ok ] - synack[ ok ] - ack[ ok ]
                                  sum[ ok ] - csum  [ ok ]
                                  ftx[ ok ] - frx   [ ok ]
                                  rtx[ ok ] - rstrx [ ok ]
                                  itx[ ok ] - irx   [ ok ]
                                  ctx[ ok ] - fclzrx[ ok ]
                                  rtx[ ok ] - rstrx [ ok ] - invert

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
---
 .../testing/selftests/net/mptcp/mptcp_join.sh | 37 +++++++++++++++++--
 1 file changed, 33 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/net/mptcp/mptcp_join.sh b/tools/testing/selftests/net/mptcp/mptcp_join.sh
index ee747f4a4c7d..2fc26fe68a9d 100755
--- a/tools/testing/selftests/net/mptcp/mptcp_join.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh
@@ -424,6 +424,7 @@ do_transfer()
 	addr_nr_ns2="$8"
 	speed="$9"
 	sflags="${10}"
+	fastclose="${11}"
 
 	port=$((10000+$TEST_COUNT))
 	TEST_COUNT=$((TEST_COUNT+1))
@@ -462,6 +463,13 @@ do_transfer()
 		extra_args="-r 10"
 	fi
 
+	if [ $fastclose -eq 2 ]; then
+		# disconnect
+		extra_args="$extra_args -I 2"
+	elif [ $fastclose -eq 3 ]; then
+		extra_args="$extra_args -I 3"
+	fi
+
 	local local_addr
 	if is_v6 "${connect_addr}"; then
 		local_addr="::"
@@ -607,7 +615,7 @@ do_transfer()
 		fi
 	fi
 
-	if [ ! -z $sflags ]; then
+	if [ $sflags != "null" ]; then
 		sleep 1
 		for netns in "$ns1" "$ns2"; do
 			pm_nl_show_endpoints $netns | while read line; do
@@ -698,7 +706,8 @@ run_tests()
 	addr_nr_ns1="${5:-0}"
 	addr_nr_ns2="${6:-0}"
 	speed="${7:-fast}"
-	sflags="${8:-""}"
+	sflags="${8:-null}"
+	fastclose="${9:-0}"
 
 	# create the input file for the failure test when
 	# the first failure test run
@@ -725,7 +734,7 @@ run_tests()
 	fi
 
 	do_transfer ${listener_ns} ${connector_ns} MPTCP MPTCP ${connect_addr} \
-		${test_linkfail} ${addr_nr_ns1} ${addr_nr_ns2} ${speed} ${sflags}
+		${test_linkfail} ${addr_nr_ns1} ${addr_nr_ns2} ${speed} ${sflags} ${fastclose}
 }
 
 dump_stats()
@@ -2285,6 +2294,21 @@ userspace_tests()
 	chk_rm_nr 0 0
 }
 
+fastclose_tests()
+{
+	reset
+	run_tests $ns1 $ns2 10.0.1.1 0 0 0 fast null 2
+	chk_join_nr "fastclose test 1" 0 0 0
+	chk_fclose_nr 1 1
+	chk_rst_nr 1 1 invert
+
+	reset
+	run_tests $ns1 $ns2 10.0.1.1 0 0 0 slow null 3
+	chk_join_nr "fastclose test 2" 0 0 0
+	chk_fclose_nr 2 2
+	chk_rst_nr 2 2 invert
+}
+
 all_tests()
 {
 	subflows_tests
@@ -2303,6 +2327,7 @@ all_tests()
 	deny_join_id0_tests
 	fullmesh_tests
 	userspace_tests
+	fastclose_tests
 }
 
 # [$1: error message]
@@ -2330,6 +2355,7 @@ usage()
 	echo "  -d deny_join_id0_tests"
 	echo "  -m fullmesh_tests"
 	echo "  -u userspace_tests"
+	echo "  -z fastclose_tests"
 	echo "  -c capture pcap files"
 	echo "  -C enable data checksum"
 	echo "  -i use ip mptcp"
@@ -2361,7 +2387,7 @@ if [ $do_all_tests -eq 1 ]; then
 	exit $ret
 fi
 
-while getopts 'fesltra64bpkdmuchCSi' opt; do
+while getopts 'fesltra64bpkdmuchzCSi' opt; do
 	case $opt in
 		f)
 			subflows_tests
@@ -2411,6 +2437,9 @@ while getopts 'fesltra64bpkdmuchCSi' opt; do
 		u)
 			userspace_tests
 			;;
+		z)
+			fastclose_tests
+			;;
 		c)
 			;;
 		C)
-- 
2.34.1