[PATCH mptcp-next 2/2] selftests: mptcp: convert iptables to nftables for mptcp_join.sh
From: Hangbin Liu
Date: Wed Sep 02 2026 - 02:54:57 EST
From: Hangbin Liu <liuhangbin@xxxxxxxxxx>
Replace the per-address-family iptables rules with a single inet table
(mjoin_table) that handles both IPv4 and IPv6. The BPF bytecode for
matching MPTCP add-addr and remove-addr suboptions is replaced with
native nft matching via "tcp option mptcp subtype". Rule handles are
captured via "nft -e --handle" so that rules can be selectively removed
during tests.
The config file adds CONFIG_NFT_NUMGEN (replaces iptables statistic nth),
CONFIG_NFT_REJECT and CONFIG_NFT_REJECT_IPV4 for reject‑related rules.
The iptables/ip6tables check inside mptcp_lib.sh is kept in case any
one still need them.
Signed-off-by: Hangbin Liu <liuhangbin@xxxxxxxxxx>
---
tools/testing/selftests/net/mptcp/config | 3 +
tools/testing/selftests/net/mptcp/mptcp_join.sh | 136 +++++++++---------------
2 files changed, 51 insertions(+), 88 deletions(-)
diff --git a/tools/testing/selftests/net/mptcp/config b/tools/testing/selftests/net/mptcp/config
index 59051ee2a986..0d0a744c4ca8 100644
--- a/tools/testing/selftests/net/mptcp/config
+++ b/tools/testing/selftests/net/mptcp/config
@@ -30,6 +30,9 @@ CONFIG_NET_SCH_NETEM=m
CONFIG_NF_TABLES=m
CONFIG_NF_TABLES_INET=y
CONFIG_NFT_COMPAT=m
+CONFIG_NFT_NUMGEN=y
+CONFIG_NFT_REJECT=m
+CONFIG_NFT_REJECT_IPV4=m
CONFIG_NFT_SOCKET=m
CONFIG_NFT_TPROXY=m
CONFIG_SYN_COOKIES=y
diff --git a/tools/testing/selftests/net/mptcp/mptcp_join.sh b/tools/testing/selftests/net/mptcp/mptcp_join.sh
index 18ce7136a2b0..05cbaddb8261 100755
--- a/tools/testing/selftests/net/mptcp/mptcp_join.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh
@@ -26,8 +26,6 @@ capout=""
cappid=""
ns1=""
ns2=""
-iptables="iptables"
-ip6tables="ip6tables"
timeout_poll=30
timeout_test=$((timeout_poll * 2 + 1))
capture=false
@@ -50,6 +48,7 @@ declare -A failed_tests
MPTCP_LIB_TEST_FORMAT="%03u %s\n"
TEST_NAME=""
nr_blank=6
+nft_handle=""
# These var are used only in some tests, make sure they are not already set
unset FAILING_LINKS
@@ -99,42 +98,6 @@ unset add_addr_tx_nr
unset add_addr_echo_tx_nr
unset add_addr_drop_tx_nr
-# generated using "nfbpf_compile '(ip && (ip[54] & 0xf0) == 0x30) ||
-# (ip6 && (ip6[74] & 0xf0) == 0x30)'"
-CBPF_MPTCP_SUBOPTION_ADD_ADDR="14,
- 48 0 0 0,
- 84 0 0 240,
- 21 0 3 64,
- 48 0 0 54,
- 84 0 0 240,
- 21 6 7 48,
- 48 0 0 0,
- 84 0 0 240,
- 21 0 4 96,
- 48 0 0 74,
- 84 0 0 240,
- 21 0 1 48,
- 6 0 0 65535,
- 6 0 0 0"
-
-# IPv4: TCP hdr of 48B, a first suboption of 12B (DACK8), the RM_ADDR suboption
-# generated using "nfbpf_compile '(ip[32] & 0xf0) == 0xc0 && ip[53] == 0x0c &&
-# (ip[66] & 0xf0) == 0x40'"
-CBPF_MPTCP_SUBOPTION_RM_ADDR="13,
- 48 0 0 0,
- 84 0 0 240,
- 21 0 9 64,
- 48 0 0 32,
- 84 0 0 240,
- 21 0 6 192,
- 48 0 0 53,
- 21 0 4 12,
- 48 0 0 66,
- 84 0 0 240,
- 21 0 1 64,
- 6 0 0 65535,
- 6 0 0 0"
-
init_partial()
{
capout=$(mktemp)
@@ -147,6 +110,14 @@ init_partial()
if $checksum; then
ip netns exec $netns sysctl -q net.mptcp.checksum_enabled=1
fi
+
+ ip netns exec "$netns" nft add table inet mjoin_table
+ ip netns exec "$netns" nft add chain inet mjoin_table input \
+ '{ type filter hook input priority filter; policy accept; }'
+ ip netns exec "$netns" nft add chain inet mjoin_table output \
+ '{ type filter hook output priority filter; policy accept; }'
+ ip netns exec "$netns" nft add chain inet mjoin_table mangle \
+ '{ type filter hook output priority mangle; policy accept; }'
done
check_invert=0
@@ -196,7 +167,7 @@ init() {
mptcp_lib_check_mptcp
mptcp_lib_check_kallsyms
- mptcp_lib_check_tools ip tc ss "${iptables}" "${ip6tables}"
+ mptcp_lib_check_tools ip tc ss nft
sin=$(mktemp)
sout=$(mktemp)
@@ -381,23 +352,18 @@ reset_with_cookies()
reset_with_add_addr_timeout()
{
local ip="${2:-4}"
- local tables
reset "${1}" || return 1
- tables="${iptables}"
- if [ $ip -eq 6 ]; then
- tables="${ip6tables}"
- fi
-
# set a maximum, to avoid too long timeout with exponential backoff
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
+
+ nft_handle=$(ip netns exec "$ns2" nft -e --handle add rule \
+ inet mjoin_table output meta nfproto ipv${ip} \
+ tcp option mptcp subtype add-addr \
+ drop | head -n1 | awk '{print $NF}')
+ if [ -z "$nft_handle" ]; then
mark_as_skipped "unable to set the 'add addr' rule"
return 1
fi
@@ -450,22 +416,16 @@ setup_fail_rules()
validate_checksum=true
local i="$1"
local ip="${2:-4}"
- local tables
- tables="${iptables}"
- if [ $ip -eq 6 ]; then
- tables="${ip6tables}"
+ nft_handle=$(ip netns exec "$ns2" nft -e --handle add rule \
+ inet mjoin_table mangle oifname ns2eth$i \
+ meta nfproto ipv${ip} meta l4proto tcp \
+ meta length 150-9999 numgen inc mod 99999 == 1 \
+ meta mark set 42 | head -n1 | awk '{print $NF}')
+ if [ -z "$nft_handle" ]; then
+ return ${KSFT_SKIP}
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 \
@@ -515,11 +475,11 @@ reset_with_tcp_filter()
local target="${3}"
local chain="${4:-INPUT}"
- if ! ip netns exec "${ns}" ${iptables} \
- -A "${chain}" \
- -s "${src}" \
- -p tcp \
- -j "${target}"; then
+ nft_handle=$(ip netns exec "$ns" nft -e --handle add rule \
+ inet mjoin_table "${chain,,}" \
+ ip saddr "{ ${src} }" meta l4proto tcp "${target,,}" | \
+ head -n1 | awk '{print $NF}')
+ if [ -z "$nft_handle" ]; then
mark_as_skipped "unable to set the filter rules"
return 1
fi
@@ -4315,10 +4275,12 @@ userspace_tests()
# force quick loss
ip netns exec $ns2 sysctl -q net.ipv4.tcp_syn_retries=1
- if ip netns exec "${ns1}" ${iptables} -A INPUT -s "10.0.1.2" \
- -p tcp --tcp-option 30 -j REJECT --reject-with tcp-reset &&
- ip netns exec "${ns2}" ${iptables} -A INPUT -d "10.0.1.2" \
- -p tcp --tcp-option 30 -j REJECT --reject-with tcp-reset; then
+ if ip netns exec "${ns1}" nft add rule inet mjoin_table \
+ input ip saddr "10.0.1.2" meta l4proto tcp \
+ tcp option mptcp exists reject with tcp reset &&
+ ip netns exec "${ns2}" nft add rule inet mjoin_table \
+ input ip daddr "10.0.1.2" meta l4proto tcp \
+ tcp option mptcp exists reject with tcp reset; then
wait_event ns2 MPTCP_LIB_EVENT_SUB_CLOSED 1
wait_event ns1 MPTCP_LIB_EVENT_SUB_CLOSED 1
chk_subflows_total 1 1
@@ -4393,7 +4355,7 @@ endpoint_tests()
chk_subflow_nr "after new reject" 2
chk_mptcp_info subflows 1 subflows 1
- ip netns exec "${ns2}" ${iptables} -D OUTPUT -s "10.0.3.2" -p tcp -j REJECT
+ ip netns exec "${ns2}" nft delete rule inet mjoin_table output handle "$nft_handle"
pm_nl_del_endpoint $ns2 3 10.0.3.2
pm_nl_add_endpoint $ns2 10.0.3.2 id 3 flags subflow
wait_mpj 3
@@ -4402,12 +4364,10 @@ endpoint_tests()
# To make sure RM_ADDR are sent over a different subflow, but
# allow the rest to quickly and cleanly close the subflow
- local ipt=1
- ip netns exec "${ns2}" ${iptables} -I OUTPUT -s "10.0.1.2" \
- -p tcp -m tcp --tcp-option 30 \
- -m bpf --bytecode \
- "$CBPF_MPTCP_SUBOPTION_RM_ADDR" \
- -j DROP || ipt=0
+ nft_handle=$(ip netns exec "${ns2}" nft -e --handle insert rule \
+ inet mjoin_table output ip saddr 10.0.1.2 meta l4proto tcp \
+ tcp option mptcp subtype remove-addr \
+ drop | head -n1 | awk '{print $NF}')
local i
for i in $(seq 3); do
pm_nl_del_endpoint $ns2 1 10.0.1.2
@@ -4420,7 +4380,8 @@ endpoint_tests()
chk_subflow_nr "after re-add id 0 ($i)" 3
chk_mptcp_info subflows 3 subflows 3
done
- [ ${ipt} = 1 ] && ip netns exec "${ns2}" ${iptables} -D OUTPUT 1
+ [ -n "${nft_handle}" ] && ip netns exec "${ns2}" nft delete rule \
+ inet mjoin_table output handle "${nft_handle}"
mptcp_lib_kill_group_wait $tests_pid
@@ -4482,18 +4443,17 @@ endpoint_tests()
# To make sure RM_ADDR are sent over a different subflow, but
# allow the rest to quickly and cleanly close the subflow
- local ipt=1
- ip netns exec "${ns1}" ${iptables} -I OUTPUT -s "10.0.1.1" \
- -p tcp -m tcp --tcp-option 30 \
- -m bpf --bytecode \
- "$CBPF_MPTCP_SUBOPTION_RM_ADDR" \
- -j DROP || ipt=0
+ nft_handle=$(ip netns exec "${ns1}" nft -e --handle insert rule \
+ inet mjoin_table output ip saddr 10.0.1.1 meta l4proto tcp \
+ tcp option mptcp subtype remove-addr \
+ drop | head -n1 | awk '{print $NF}')
pm_nl_del_endpoint $ns1 42 10.0.1.1
sleep 0.5
chk_subflow_nr "after delete ID 0" 2
chk_mptcp_info subflows 2 subflows 2
chk_mptcp_info add_addr_signal 2 add_addr_accepted 2
- [ ${ipt} = 1 ] && ip netns exec "${ns1}" ${iptables} -D OUTPUT 1
+ [ -n "${nft_handle}" ] && ip netns exec "${ns1}" nft delete rule \
+ inet mjoin_table output handle "${nft_handle}"
pm_nl_add_endpoint $ns1 10.0.1.1 id 42 flags signal
wait_mpj 4
@@ -4555,7 +4515,7 @@ endpoint_tests()
pm_nl_flush_endpoint $ns2
pm_nl_flush_endpoint $ns1
wait_rm_addr $ns2 0
- ip netns exec "${ns2}" ${iptables} -D OUTPUT -s "10.0.3.2" -p tcp -j REJECT
+ ip netns exec "${ns2}" nft delete rule inet mjoin_table output handle "$nft_handle"
pm_nl_add_endpoint $ns2 10.0.3.2 id 3 flags subflow
wait_mpj 1
pm_nl_add_endpoint $ns1 10.0.3.1 id 2 flags signal
--
2.55.0