11 files changed, 776 insertions, 26 deletions
diff --git a/include/net/netns/netfilter.h b/include/net/netns/netfilter.h
index 02bbdc577f8e..a6a0bf4a247e 100644
--- a/include/net/netns/netfilter.h
+++ b/include/net/netns/netfilter.h
@@ -15,6 +15,9 @@ struct netns_nf {
 	const struct nf_logger __rcu *nf_loggers[NFPROTO_NUMPROTO];
 #ifdef CONFIG_SYSCTL
 	struct ctl_table_header *nf_log_dir_header;
+#ifdef CONFIG_LWTUNNEL
+	struct ctl_table_header *nf_lwtnl_dir_header;
+#endif
 #endif
 	struct nf_hook_entries __rcu *hooks_ipv4[NF_INET_NUMHOOKS];
 	struct nf_hook_entries __rcu *hooks_ipv6[NF_INET_NUMHOOKS];
diff --git a/net/ipv6/seg6_local.c b/net/ipv6/seg6_local.c
index 24e2b4b494cb..c434940131b1 100644
--- a/net/ipv6/seg6_local.c
+++ b/net/ipv6/seg6_local.c
@@ -941,8 +941,8 @@ static int input_action_end_dx6(struct sk_buff *skb,
 
 	if (static_branch_unlikely(&nf_hooks_lwtunnel_enabled))
 		return NF_HOOK(NFPROTO_IPV6, NF_INET_PRE_ROUTING,
-			       dev_net(skb->dev), NULL, skb, NULL,
-			       skb_dst(skb)->dev, input_action_end_dx6_finish);
+			       dev_net(skb->dev), NULL, skb, skb->dev,
+			       NULL, input_action_end_dx6_finish);
 
 	return input_action_end_dx6_finish(dev_net(skb->dev), NULL, skb);
 drop:
@@ -991,8 +991,8 @@ static int input_action_end_dx4(struct sk_buff *skb,
 
 	if (static_branch_unlikely(&nf_hooks_lwtunnel_enabled))
 		return NF_HOOK(NFPROTO_IPV4, NF_INET_PRE_ROUTING,
-			       dev_net(skb->dev), NULL, skb, NULL,
-			       skb_dst(skb)->dev, input_action_end_dx4_finish);
+			       dev_net(skb->dev), NULL, skb, skb->dev,
+			       NULL, input_action_end_dx4_finish);
 
 	return input_action_end_dx4_finish(dev_net(skb->dev), NULL, skb);
 drop:
diff --git a/net/netfilter/core.c b/net/netfilter/core.c
index 3126911f5042..b00fc285b334 100644
--- a/net/netfilter/core.c
+++ b/net/netfilter/core.c
@@ -815,12 +815,21 @@ int __init netfilter_init(void)
 	if (ret < 0)
 		goto err;
 
+#ifdef CONFIG_LWTUNNEL
+	ret = netfilter_lwtunnel_init();
+	if (ret < 0)
+		goto err_lwtunnel_pernet;
+#endif
 	ret = netfilter_log_init();
 	if (ret < 0)
-		goto err_pernet;
+		goto err_log_pernet;
 
 	return 0;
-err_pernet:
+err_log_pernet:
+#ifdef CONFIG_LWTUNNEL
+	netfilter_lwtunnel_fini();
+err_lwtunnel_pernet:
+#endif
 	unregister_pernet_subsys(&netfilter_net_ops);
 err:
 	return ret;
diff --git a/net/netfilter/ipset/ip_set_core.c b/net/netfilter/ipset/ip_set_core.c
index c7ae4d9bf3d2..61431690cbd5 100644
--- a/net/netfilter/ipset/ip_set_core.c
+++ b/net/netfilter/ipset/ip_set_core.c
@@ -53,12 +53,13 @@ MODULE_DESCRIPTION("core IP set support");
 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_IPSET);
 
 /* When the nfnl mutex or ip_set_ref_lock is held: */
-#define ip_set_dereference(p)		\
-	rcu_dereference_protected(p,	\
+#define ip_set_dereference(inst)	\
+	rcu_dereference_protected((inst)->ip_set_list,	\
 		lockdep_nfnl_is_held(NFNL_SUBSYS_IPSET) || \
-		lockdep_is_held(&ip_set_ref_lock))
+		lockdep_is_held(&ip_set_ref_lock) || \
+		(inst)->is_deleted)
 #define ip_set(inst, id)		\
-	ip_set_dereference((inst)->ip_set_list)[id]
+	ip_set_dereference(inst)[id]
 #define ip_set_ref_netlink(inst,id)	\
 	rcu_dereference_raw((inst)->ip_set_list)[id]
 #define ip_set_dereference_nfnl(p)	\
@@ -1133,7 +1134,7 @@ static int ip_set_create(struct sk_buff *skb, const struct nfnl_info *info,
 		if (!list)
 			goto cleanup;
 		/* nfnl mutex is held, both lists are valid */
-		tmp = ip_set_dereference(inst->ip_set_list);
+		tmp = ip_set_dereference(inst);
 		memcpy(list, tmp, sizeof(struct ip_set *) * inst->ip_set_max);
 		rcu_assign_pointer(inst->ip_set_list, list);
 		/* Make sure all current packets have passed through */
diff --git a/net/netfilter/nf_conntrack_standalone.c b/net/netfilter/nf_conntrack_standalone.c
index 74112e9c5dab..6c40bdf8b05a 100644
--- a/net/netfilter/nf_conntrack_standalone.c
+++ b/net/netfilter/nf_conntrack_standalone.c
@@ -22,9 +22,6 @@
 #include <net/netfilter/nf_conntrack_acct.h>
 #include <net/netfilter/nf_conntrack_zones.h>
 #include <net/netfilter/nf_conntrack_timestamp.h>
-#ifdef CONFIG_LWTUNNEL
-#include <net/netfilter/nf_hooks_lwtunnel.h>
-#endif
 #include <linux/rculist_nulls.h>
 
 static bool enable_hooks __read_mostly;
@@ -612,9 +609,6 @@ enum nf_ct_sysctl_index {
 	NF_SYSCTL_CT_PROTO_TIMEOUT_GRE,
 	NF_SYSCTL_CT_PROTO_TIMEOUT_GRE_STREAM,
 #endif
-#ifdef CONFIG_LWTUNNEL
-	NF_SYSCTL_CT_LWTUNNEL,
-#endif
 
 	NF_SYSCTL_CT_LAST_SYSCTL,
 };
@@ -946,15 +940,6 @@ static struct ctl_table nf_ct_sysctl_table[] = {
 		.proc_handler   = proc_dointvec_jiffies,
 	},
 #endif
-#ifdef CONFIG_LWTUNNEL
-	[NF_SYSCTL_CT_LWTUNNEL] = {
-		.procname	= "nf_hooks_lwtunnel",
-		.data		= NULL,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= nf_hooks_lwtunnel_sysctl_handler,
-	},
-#endif
 };
 
 static struct ctl_table nf_ct_netfilter_table[] = {
diff --git a/net/netfilter/nf_hooks_lwtunnel.c b/net/netfilter/nf_hooks_lwtunnel.c
index 00e89ffd78f6..7cdb59bb4459 100644
--- a/net/netfilter/nf_hooks_lwtunnel.c
+++ b/net/netfilter/nf_hooks_lwtunnel.c
@@ -3,6 +3,9 @@
 #include <linux/sysctl.h>
 #include <net/lwtunnel.h>
 #include <net/netfilter/nf_hooks_lwtunnel.h>
+#include <linux/netfilter.h>
+
+#include "nf_internals.h"
 
 static inline int nf_hooks_lwtunnel_get(void)
 {
@@ -50,4 +53,68 @@ int nf_hooks_lwtunnel_sysctl_handler(struct ctl_table *table, int write,
 	return ret;
 }
 EXPORT_SYMBOL_GPL(nf_hooks_lwtunnel_sysctl_handler);
+
+static struct ctl_table nf_lwtunnel_sysctl_table[] = {
+	{
+		.procname	= "nf_hooks_lwtunnel",
+		.data		= NULL,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= nf_hooks_lwtunnel_sysctl_handler,
+	},
+};
+
+static int __net_init nf_lwtunnel_net_init(struct net *net)
+{
+	struct ctl_table_header *hdr;
+	struct ctl_table *table;
+
+	table = nf_lwtunnel_sysctl_table;
+	if (!net_eq(net, &init_net)) {
+		table = kmemdup(nf_lwtunnel_sysctl_table,
+				sizeof(nf_lwtunnel_sysctl_table),
+				GFP_KERNEL);
+		if (!table)
+			goto err_alloc;
+	}
+
+	hdr = register_net_sysctl_sz(net, "net/netfilter", table,
+				     ARRAY_SIZE(nf_lwtunnel_sysctl_table));
+	if (!hdr)
+		goto err_reg;
+
+	net->nf.nf_lwtnl_dir_header = hdr;
+
+	return 0;
+err_reg:
+	if (!net_eq(net, &init_net))
+		kfree(table);
+err_alloc:
+	return -ENOMEM;
+}
+
+static void __net_exit nf_lwtunnel_net_exit(struct net *net)
+{
+	const struct ctl_table *table;
+
+	table = net->nf.nf_lwtnl_dir_header->ctl_table_arg;
+	unregister_net_sysctl_table(net->nf.nf_lwtnl_dir_header);
+	if (!net_eq(net, &init_net))
+		kfree(table);
+}
+
+static struct pernet_operations nf_lwtunnel_net_ops = {
+	.init = nf_lwtunnel_net_init,
+	.exit = nf_lwtunnel_net_exit,
+};
+
+int __init netfilter_lwtunnel_init(void)
+{
+	return register_pernet_subsys(&nf_lwtunnel_net_ops);
+}
+
+void netfilter_lwtunnel_fini(void)
+{
+	unregister_pernet_subsys(&nf_lwtunnel_net_ops);
+}
 #endif /* CONFIG_SYSCTL */
diff --git a/net/netfilter/nf_internals.h b/net/netfilter/nf_internals.h
index 832ae64179f0..25403023060b 100644
--- a/net/netfilter/nf_internals.h
+++ b/net/netfilter/nf_internals.h
@@ -29,6 +29,12 @@ void nf_queue_nf_hook_drop(struct net *net);
 /* nf_log.c */
 int __init netfilter_log_init(void);
 
+#ifdef CONFIG_LWTUNNEL
+/* nf_hooks_lwtunnel.c */
+int __init netfilter_lwtunnel_init(void);
+void netfilter_lwtunnel_fini(void);
+#endif
+
 /* core.c */
 void nf_hook_entries_delete_raw(struct nf_hook_entries __rcu **pp,
 				const struct nf_hook_ops *reg);
diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile
index bd01e4a0be2c..d9393569d03a 100644
--- a/tools/testing/selftests/net/Makefile
+++ b/tools/testing/selftests/net/Makefile
@@ -43,6 +43,8 @@ TEST_PROGS += srv6_hl2encap_red_l2vpn_test.sh
 TEST_PROGS += srv6_end_next_csid_l3vpn_test.sh
 TEST_PROGS += srv6_end_x_next_csid_l3vpn_test.sh
 TEST_PROGS += srv6_end_flavors_test.sh
+TEST_PROGS += srv6_end_dx4_netfilter_test.sh
+TEST_PROGS += srv6_end_dx6_netfilter_test.sh
 TEST_PROGS += vrf_strict_mode_test.sh
 TEST_PROGS += arp_ndisc_evict_nocarrier.sh
 TEST_PROGS += ndisc_unsolicited_na_test.sh
diff --git a/tools/testing/selftests/net/config b/tools/testing/selftests/net/config
index 04de7a6ba6f3..d4891f7a2bfa 100644
--- a/tools/testing/selftests/net/config
+++ b/tools/testing/selftests/net/config
@@ -101,3 +101,5 @@ CONFIG_NETFILTER_XT_MATCH_POLICY=m
 CONFIG_CRYPTO_ARIA=y
 CONFIG_XFRM_INTERFACE=m
 CONFIG_XFRM_USER=m
+CONFIG_IP_NF_MATCH_RPFILTER=m
+CONFIG_IP6_NF_MATCH_RPFILTER=m
diff --git a/tools/testing/selftests/net/srv6_end_dx4_netfilter_test.sh b/tools/testing/selftests/net/srv6_end_dx4_netfilter_test.sh
new file mode 100755
index 000000000000..e23210aa547f
--- /dev/null
+++ b/tools/testing/selftests/net/srv6_end_dx4_netfilter_test.sh
@@ -0,0 +1,335 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# author: Jianguo Wu <wujianguo@chinatelecom.cn>
+#
+# Mostly copied from tools/testing/selftests/net/srv6_end_dt4_l3vpn_test.sh.
+#
+# This script is designed for testing the support of netfilter hooks for
+# SRv6 End.DX4 behavior.
+#
+# Hereafter a network diagram is shown, where one tenants (named 100) offer
+# IPv4 L3 VPN services allowing hosts to communicate with each other across
+# an IPv6 network.
+#
+# Routers rt-1 and rt-2 implement IPv4 L3 VPN services leveraging the SRv6
+# architecture. The key components for such VPNs are: a) SRv6 Encap behavior,
+# b) SRv6 End.DX4 behavior.
+#
+# To explain how an IPv4 L3 VPN based on SRv6 works, let us briefly consider an
+# example where, within the same domain of tenant 100, the host hs-1 pings
+# the host hs-2.
+#
+# First of all, L2 reachability of the host hs-2 is taken into account by
+# the router rt-1 which acts as an arp proxy.
+#
+# When the host hs-1 sends an IPv4 packet destined to hs-2, the router rt-1
+# receives the packet on the internal veth-t100 interface, rt-1 contains the
+# SRv6 Encap route for encapsulating the IPv4 packet in a IPv6 plus the Segment
+# Routing Header (SRH) packet. This packet is sent through the (IPv6) core
+# network up to the router rt-2 that receives it on veth0 interface.
+#
+# The rt-2 router uses the 'localsid' routing table to process incoming
+# IPv6+SRH packets which belong to the VPN of the tenant 100. For each of these
+# packets, the SRv6 End.DX4 behavior removes the outer IPv6+SRH headers and
+# routs the packet to the specified nexthop. Afterwards, the packet is sent to
+# the host hs-2 through the veth-t100 interface.
+#
+# The ping response follows the same processing but this time the role of rt-1
+# and rt-2 are swapped.
+#
+# And when net.netfilter.nf_hooks_lwtunnel is set to 1 in rt-1 or rt-2, and a
+# rpfilter iptables rule is added, SRv6 packets will go through netfilter PREROUTING
+# hooks.
+#
+#
+# +-------------------+                                   +-------------------+
+# |                   |                                   |                   |
+# |    hs-1 netns     |                                   |     hs-2 netns    |
+# |                   |                                   |                   |
+# |  +-------------+  |                                   |  +-------------+  |
+# |  |    veth0    |  |                                   |  |    veth0    |  |
+# |  | 10.0.0.1/24 |  |                                   |  | 10.0.0.2/24 |  |
+# |  +-------------+  |                                   |  +-------------+  |
+# |        .          |                                   |         .         |
+# +-------------------+                                   +-------------------+
+#          .                                                        .
+#          .                                                        .
+#          .                                                        .
+# +-----------------------------------+   +-----------------------------------+
+# |        .                          |   |                         .         |
+# | +---------------+                 |   |                 +---------------- |
+# | |   veth-t100   |                 |   |                 |   veth-t100   | |
+# | | 10.0.0.11/24  |    +----------+ |   | +----------+    | 10.0.0.22/24  | |
+# | +-------+-------+   |   route   | |   | |   route  |    +-------+-------- |
+# |                     |   table   | |   | |   table  |                      |
+# |                      +----------+ |   | +----------+                      |
+# |                  +--------------+ |   | +--------------+                  |
+# |                 |      veth0    | |   | |   veth0       |                 |
+# |                 | 2001:11::1/64 |.|...|.| 2001:11::2/64 |                 |
+# |                  +--------------+ |   | +--------------+                  |
+# |                                   |   |                                   |
+# |                        rt-1 netns |   | rt-2 netns                        |
+# |                                   |   |                                   |
+# +-----------------------------------+   +-----------------------------------+
+#
+# ~~~~~~~~~~~~~~~~~~~~~~~~~
+# | Network configuration |
+# ~~~~~~~~~~~~~~~~~~~~~~~~~
+#
+# rt-1: localsid table
+# +----------------------------------------------------------------+
+# |SID              |Action                                        |
+# +----------------------------------------------------------------+
+# |fc00:21:100::6004|apply SRv6 End.DX4 nh4 10.0.0.1 dev veth-t100 |
+# +----------------------------------------------------------------+
+#
+# rt-1: route table
+# +---------------------------------------------------+
+# |host       |Action                                 |
+# +---------------------------------------------------+
+# |10.0.0.2   |apply seg6 encap segs fc00:12:100::6004|
+# +---------------------------------------------------+
+# |10.0.0.0/24|forward to dev veth_t100               |
+# +---------------------------------------------------+
+#
+#
+# rt-2: localsid table
+# +---------------------------------------------------------------+
+# |SID              |Action                                       |
+# +---------------------------------------------------------------+
+# |fc00:12:100::6004|apply SRv6 End.DX4 nh4 10.0.0.2 dev veth-t100|
+# +---------------------------------------------------------------+
+#
+# rt-2: route table
+# +---------------------------------------------------+
+# |host       |Action                                 |
+# +---------------------------------------------------+
+# |10.0.0.1   |apply seg6 encap segs fc00:21:100::6004|
+# +---------------------------------------------------+
+# |10.0.0.0/24|forward to dev veth_t100               |
+# +---------------------------------------------------+
+#
+
+# Kselftest framework requirement - SKIP code is 4.
+ksft_skip=4
+
+readonly IPv6_RT_NETWORK=2001:11
+readonly IPv4_HS_NETWORK=10.0.0
+readonly SID_LOCATOR=fc00
+
+PING_TIMEOUT_SEC=4
+
+ret=0
+
+PAUSE_ON_FAIL=${PAUSE_ON_FAIL:=no}
+
+log_test()
+{
+	local rc=$1
+	local expected=$2
+	local msg="$3"
+
+	if [ ${rc} -eq ${expected} ]; then
+		nsuccess=$((nsuccess+1))
+		printf "\n    TEST: %-60s  [ OK ]\n" "${msg}"
+	else
+		ret=1
+		nfail=$((nfail+1))
+		printf "\n    TEST: %-60s  [FAIL]\n" "${msg}"
+		if [ "${PAUSE_ON_FAIL}" = "yes" ]; then
+			echo
+			echo "hit enter to continue, 'q' to quit"
+			read a
+			[ "$a" = "q" ] && exit 1
+		fi
+	fi
+}
+
+print_log_test_results()
+{
+	if [ "$TESTS" != "none" ]; then
+		printf "\nTests passed: %3d\n" ${nsuccess}
+		printf "Tests failed: %3d\n"   ${nfail}
+	fi
+}
+
+log_section()
+{
+	echo
+	echo "################################################################################"
+	echo "TEST SECTION: $*"
+	echo "################################################################################"
+}
+
+cleanup()
+{
+	ip link del veth-rt-1 2>/dev/null || true
+	ip link del veth-rt-2 2>/dev/null || true
+
+	# destroy routers rt-* and hosts hs-*
+	for ns in $(ip netns show | grep -E 'rt-*|hs-*'); do
+		ip netns del ${ns} || true
+	done
+}
+
+# Setup the basic networking for the routers
+setup_rt_networking()
+{
+	local rt=$1
+	local nsname=rt-${rt}
+
+	ip netns add ${nsname}
+
+	ip netns exec ${nsname} sysctl -wq net.ipv6.conf.all.accept_dad=0
+	ip netns exec ${nsname} sysctl -wq net.ipv6.conf.default.accept_dad=0
+
+	ip link set veth-rt-${rt} netns ${nsname}
+	ip -netns ${nsname} link set veth-rt-${rt} name veth0
+
+	ip -netns ${nsname} addr add ${IPv6_RT_NETWORK}::${rt}/64 dev veth0 nodad
+	ip -netns ${nsname} link set veth0 up
+	ip -netns ${nsname} link set lo up
+
+	ip netns exec ${nsname} sysctl -wq net.ipv4.ip_forward=1
+	ip netns exec ${nsname} sysctl -wq net.ipv6.conf.all.forwarding=1
+}
+
+setup_rt_netfilter()
+{
+	local rt=$1
+	local nsname=rt-${rt}
+
+	ip netns exec ${nsname} sysctl -wq net.netfilter.nf_hooks_lwtunnel=1
+	ip netns exec ${nsname} iptables -t raw -A PREROUTING -m rpfilter --invert -j DROP
+}
+
+setup_hs()
+{
+	local hs=$1
+	local rt=$2
+	local tid=$3
+	local hsname=hs-${hs}
+	local rtname=rt-${rt}
+	local rtveth=veth-t${tid}
+
+	# set the networking for the host
+	ip netns add ${hsname}
+
+	ip -netns ${hsname} link add veth0 type veth peer name ${rtveth}
+	ip -netns ${hsname} link set ${rtveth} netns ${rtname}
+	ip -netns ${hsname} addr add ${IPv4_HS_NETWORK}.${hs}/24 dev veth0
+	ip -netns ${hsname} link set veth0 up
+	ip -netns ${hsname} link set lo up
+
+	ip -netns ${rtname} addr add ${IPv4_HS_NETWORK}.${rt}${hs}/24 dev ${rtveth}
+	ip -netns ${rtname} link set ${rtveth} up
+
+	ip netns exec ${rtname} sysctl -wq net.ipv4.conf.${rtveth}.proxy_arp=1
+}
+
+setup_vpn_config()
+{
+	local hssrc=$1
+	local rtsrc=$2
+	local hsdst=$3
+	local rtdst=$4
+	local tid=$5
+
+	local hssrc_name=hs-t${tid}-${hssrc}
+	local hsdst_name=hs-t${tid}-${hsdst}
+	local rtsrc_name=rt-${rtsrc}
+	local rtdst_name=rt-${rtdst}
+	local vpn_sid=${SID_LOCATOR}:${hssrc}${hsdst}:${tid}::6004
+
+	# set the encap route for encapsulating packets which arrive from the
+	# host hssrc and destined to the access router rtsrc.
+	ip -netns ${rtsrc_name} -4 route add ${IPv4_HS_NETWORK}.${hsdst}/32 \
+		encap seg6 mode encap segs ${vpn_sid} dev veth0
+	ip -netns ${rtsrc_name} -6 route add ${vpn_sid}/128 \
+		via 2001:11::${rtdst} dev veth0
+
+	# set the decap route for decapsulating packets which arrive from
+	# the rtdst router and destined to the hsdst host.
+	ip -netns ${rtdst_name} -6 route add ${vpn_sid}/128 \
+		encap seg6local action End.DX4 nh4 ${IPv4_HS_NETWORK}.${hsdst} dev veth-t${tid}
+}
+
+setup()
+{
+	ip link add veth-rt-1 type veth peer name veth-rt-2
+	# setup the networking for router rt-1 and router rt-2
+	setup_rt_networking 1
+	setup_rt_networking 2
+
+	# setup two hosts for the tenant 100.
+	#  - host hs-1 is directly connected to the router rt-1;
+	#  - host hs-2 is directly connected to the router rt-2.
+	setup_hs 1 1 100
+	setup_hs 2 2 100
+
+	# setup the IPv4 L3 VPN which connects the host hs-1 and host hs-2.
+	setup_vpn_config 1 1 2 2 100  #args: src_host src_router dst_host dst_router tenant
+	setup_vpn_config 2 2 1 1 100
+}
+
+check_hs_connectivity()
+{
+	local hssrc=$1
+	local hsdst=$2
+	local tid=$3
+
+	ip netns exec hs-${hssrc} ping -c 1 -W ${PING_TIMEOUT_SEC} \
+		${IPv4_HS_NETWORK}.${hsdst} >/dev/null 2>&1
+}
+
+check_and_log_hs_connectivity()
+{
+	local hssrc=$1
+	local hsdst=$2
+	local tid=$3
+
+	check_hs_connectivity ${hssrc} ${hsdst} ${tid}
+	log_test $? 0 "Hosts connectivity: hs-${hssrc} -> hs-${hsdst} (tenant ${tid})"
+}
+
+host_tests()
+{
+	log_section "SRv6 VPN connectivity test among hosts in the same tenant"
+
+	check_and_log_hs_connectivity 1 2 100
+	check_and_log_hs_connectivity 2 1 100
+}
+
+router_netfilter_tests()
+{
+	log_section "SRv6 VPN connectivity test with netfilter enabled in routers"
+	setup_rt_netfilter 1
+	setup_rt_netfilter 2
+
+	check_and_log_hs_connectivity 1 2 100
+	check_and_log_hs_connectivity 2 1 100
+}
+
+if [ "$(id -u)" -ne 0 ];then
+	echo "SKIP: Need root privileges"
+	exit $ksft_skip
+fi
+
+if [ ! -x "$(command -v ip)" ]; then
+	echo "SKIP: Could not run test without ip tool"
+	exit $ksft_skip
+fi
+
+cleanup &>/dev/null
+
+setup
+
+host_tests
+router_netfilter_tests
+
+print_log_test_results
+
+cleanup &>/dev/null
+
+exit ${ret}
diff --git a/tools/testing/selftests/net/srv6_end_dx6_netfilter_test.sh b/tools/testing/selftests/net/srv6_end_dx6_netfilter_test.sh
new file mode 100755
index 000000000000..9e69a2ed5bc3
--- /dev/null
+++ b/tools/testing/selftests/net/srv6_end_dx6_netfilter_test.sh
@@ -0,0 +1,340 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# author: Jianguo Wu <wujianguo@chinatelecom.cn>
+#
+# Mostly copied from tools/testing/selftests/net/srv6_end_dt6_l3vpn_test.sh.
+#
+# This script is designed for testing the support of netfilter hooks for
+# SRv6 End.DX4 behavior.
+#
+# Hereafter a network diagram is shown, where one tenants (named 100) offer
+# IPv6 L3 VPN services allowing hosts to communicate with each other across
+# an IPv6 network.
+#
+# Routers rt-1 and rt-2 implement IPv6 L3 VPN services leveraging the SRv6
+# architecture. The key components for such VPNs are: a) SRv6 Encap behavior,
+# b) SRv6 End.DX4 behavior.
+#
+# To explain how an IPv6 L3 VPN based on SRv6 works, let us briefly consider an
+# example where, within the same domain of tenant 100, the host hs-1 pings
+# the host hs-2.
+#
+# First of all, L2 reachability of the host hs-2 is taken into account by
+# the router rt-1 which acts as an arp proxy.
+#
+# When the host hs-1 sends an IPv6 packet destined to hs-2, the router rt-1
+# receives the packet on the internal veth-t100 interface, rt-1 contains the
+# SRv6 Encap route for encapsulating the IPv6 packet in a IPv6 plus the Segment
+# Routing Header (SRH) packet. This packet is sent through the (IPv6) core
+# network up to the router rt-2 that receives it on veth0 interface.
+#
+# The rt-2 router uses the 'localsid' routing table to process incoming
+# IPv6+SRH packets which belong to the VPN of the tenant 100. For each of these
+# packets, the SRv6 End.DX4 behavior removes the outer IPv6+SRH headers and
+# routs the packet to the specified nexthop. Afterwards, the packet is sent to
+# the host hs-2 through the veth-t100 interface.
+#
+# The ping response follows the same processing but this time the role of rt-1
+# and rt-2 are swapped.
+#
+# And when net.netfilter.nf_hooks_lwtunnel is set to 1 in rt-1 or rt-2, and a
+# rpfilter iptables rule is added, SRv6 packets will go through netfilter PREROUTING
+# hooks.
+#
+#
+# +-------------------+                                   +-------------------+
+# |                   |                                   |                   |
+# |    hs-1 netns     |                                   |     hs-2 netns    |
+# |                   |                                   |                   |
+# |  +-------------+  |                                   |  +-------------+  |
+# |  |    veth0    |  |                                   |  |    veth0    |  |
+# |  | cafe::1/64  |  |                                   |  | cafe::2/64  |  |
+# |  +-------------+  |                                   |  +-------------+  |
+# |        .          |                                   |         .         |
+# +-------------------+                                   +-------------------+
+#          .                                                        .
+#          .                                                        .
+#          .                                                        .
+# +-----------------------------------+   +-----------------------------------+
+# |        .                          |   |                         .         |
+# | +---------------+                 |   |                 +---------------- |
+# | |   veth-t100   |                 |   |                 |   veth-t100   | |
+# | | cafe::11/64   |    +----------+ |   | +----------+    | cafe::22/64   | |
+# | +-------+-------+   |   route   | |   | |   route  |    +-------+-------- |
+# |                     |   table   | |   | |   table  |                      |
+# |                      +----------+ |   | +----------+                      |
+# |                  +--------------+ |   | +--------------+                  |
+# |                 |      veth0    | |   | |   veth0       |                 |
+# |                 | 2001:11::1/64 |.|...|.| 2001:11::2/64 |                 |
+# |                  +--------------+ |   | +--------------+                  |
+# |                                   |   |                                   |
+# |                        rt-1 netns |   | rt-2 netns                        |
+# |                                   |   |                                   |
+# +-----------------------------------+   +-----------------------------------+
+#
+# ~~~~~~~~~~~~~~~~~~~~~~~~~
+# | Network configuration |
+# ~~~~~~~~~~~~~~~~~~~~~~~~~
+#
+# rt-1: localsid table
+# +----------------------------------------------------------------+
+# |SID              |Action                                        |
+# +----------------------------------------------------------------+
+# |fc00:21:100::6004|apply SRv6 End.DX6 nh6 cafe::1 dev veth-t100  |
+# +----------------------------------------------------------------+
+#
+# rt-1: route table
+# +---------------------------------------------------+
+# |host       |Action                                 |
+# +---------------------------------------------------+
+# |cafe::2    |apply seg6 encap segs fc00:12:100::6004|
+# +---------------------------------------------------+
+# |cafe::/64  |forward to dev veth_t100               |
+# +---------------------------------------------------+
+#
+#
+# rt-2: localsid table
+# +---------------------------------------------------------------+
+# |SID              |Action                                       |
+# +---------------------------------------------------------------+
+# |fc00:12:100::6004|apply SRv6 End.DX6 nh6 cafe::2 dev veth-t100 |
+# +---------------------------------------------------------------+
+#
+# rt-2: route table
+# +---------------------------------------------------+
+# |host       |Action                                 |
+# +---------------------------------------------------+
+# |cafe::1    |apply seg6 encap segs fc00:21:100::6004|
+# +---------------------------------------------------+
+# |cafe::/64  |forward to dev veth_t100               |
+# +---------------------------------------------------+
+#
+
+# Kselftest framework requirement - SKIP code is 4.
+ksft_skip=4
+
+readonly IPv6_RT_NETWORK=2001:11
+readonly IPv6_HS_NETWORK=cafe
+readonly SID_LOCATOR=fc00
+
+PING_TIMEOUT_SEC=4
+
+ret=0
+
+PAUSE_ON_FAIL=${PAUSE_ON_FAIL:=no}
+
+log_test()
+{
+	local rc=$1
+	local expected=$2
+	local msg="$3"
+
+	if [ ${rc} -eq ${expected} ]; then
+		nsuccess=$((nsuccess+1))
+		printf "\n    TEST: %-60s  [ OK ]\n" "${msg}"
+	else
+		ret=1
+		nfail=$((nfail+1))
+		printf "\n    TEST: %-60s  [FAIL]\n" "${msg}"
+		if [ "${PAUSE_ON_FAIL}" = "yes" ]; then
+			echo
+			echo "hit enter to continue, 'q' to quit"
+			read a
+			[ "$a" = "q" ] && exit 1
+		fi
+	fi
+}
+
+print_log_test_results()
+{
+	if [ "$TESTS" != "none" ]; then
+		printf "\nTests passed: %3d\n" ${nsuccess}
+		printf "Tests failed: %3d\n"   ${nfail}
+	fi
+}
+
+log_section()
+{
+	echo
+	echo "################################################################################"
+	echo "TEST SECTION: $*"
+	echo "################################################################################"
+}
+
+cleanup()
+{
+	ip link del veth-rt-1 2>/dev/null || true
+	ip link del veth-rt-2 2>/dev/null || true
+
+	# destroy routers rt-* and hosts hs-*
+	for ns in $(ip netns show | grep -E 'rt-*|hs-*'); do
+		ip netns del ${ns} || true
+	done
+}
+
+# Setup the basic networking for the routers
+setup_rt_networking()
+{
+	local rt=$1
+	local nsname=rt-${rt}
+
+	ip netns add ${nsname}
+
+	ip netns exec ${nsname} sysctl -wq net.ipv6.conf.all.accept_dad=0
+	ip netns exec ${nsname} sysctl -wq net.ipv6.conf.default.accept_dad=0
+
+	ip link set veth-rt-${rt} netns ${nsname}
+	ip -netns ${nsname} link set veth-rt-${rt} name veth0
+
+	ip -netns ${nsname} addr add ${IPv6_RT_NETWORK}::${rt}/64 dev veth0 nodad
+	ip -netns ${nsname} link set veth0 up
+	ip -netns ${nsname} link set lo up
+
+	ip netns exec ${nsname} sysctl -wq net.ipv6.conf.all.forwarding=1
+}
+
+setup_rt_netfilter()
+{
+	local rt=$1
+	local nsname=rt-${rt}
+
+	ip netns exec ${nsname} sysctl -wq net.netfilter.nf_hooks_lwtunnel=1
+	ip netns exec ${nsname} ip6tables -t raw -A PREROUTING -m rpfilter --invert -j DROP
+}
+
+setup_hs()
+{
+	local hs=$1
+	local rt=$2
+	local tid=$3
+	local hsname=hs-${hs}
+	local rtname=rt-${rt}
+	local rtveth=veth-t${tid}
+
+	# set the networking for the host
+	ip netns add ${hsname}
+
+	ip -netns ${hsname} link add veth0 type veth peer name ${rtveth}
+	ip -netns ${hsname} link set ${rtveth} netns ${rtname}
+	ip -netns ${hsname} addr add ${IPv6_HS_NETWORK}::${hs}/64 dev veth0 nodad
+	ip -netns ${hsname} link set veth0 up
+	ip -netns ${hsname} link set lo up
+
+	ip -netns ${rtname} addr add ${IPv6_HS_NETWORK}::${rt}${hs}/64 dev ${rtveth}
+	ip -netns ${rtname} link set ${rtveth} up
+
+	ip netns exec ${rtname} sysctl -wq net.ipv6.conf.all.accept_dad=0
+	ip netns exec ${rtname} sysctl -wq net.ipv6.conf.default.accept_dad=0
+
+	ip netns exec ${rtname} sysctl -wq net.ipv6.conf.${rtveth}.proxy_ndp=1
+}
+
+setup_vpn_config()
+{
+	local hssrc=$1
+	local rtsrc=$2
+	local hsdst=$3
+	local rtdst=$4
+	local tid=$5
+
+	local hssrc_name=hs-t${tid}-${hssrc}
+	local hsdst_name=hs-t${tid}-${hsdst}
+	local rtsrc_name=rt-${rtsrc}
+	local rtdst_name=rt-${rtdst}
+	local rtveth=veth-t${tid}
+	local vpn_sid=${SID_LOCATOR}:${hssrc}${hsdst}:${tid}::6004
+
+	ip -netns ${rtsrc_name} -6 neigh add proxy ${IPv6_HS_NETWORK}::${hsdst} dev ${rtveth}
+
+	# set the encap route for encapsulating packets which arrive from the
+	# host hssrc and destined to the access router rtsrc.
+	ip -netns ${rtsrc_name} -6 route add ${IPv6_HS_NETWORK}::${hsdst}/128 \
+		encap seg6 mode encap segs ${vpn_sid} dev veth0
+	ip -netns ${rtsrc_name} -6 route add ${vpn_sid}/128 \
+		via 2001:11::${rtdst} dev veth0
+
+	# set the decap route for decapsulating packets which arrive from
+	# the rtdst router and destined to the hsdst host.
+	ip -netns ${rtdst_name} -6 route add ${vpn_sid}/128 \
+		encap seg6local action End.DX6 nh6 ${IPv6_HS_NETWORK}::${hsdst} dev veth-t${tid}
+}
+
+setup()
+{
+	ip link add veth-rt-1 type veth peer name veth-rt-2
+	# setup the networking for router rt-1 and router rt-2
+	setup_rt_networking 1
+	setup_rt_networking 2
+
+	# setup two hosts for the tenant 100.
+	#  - host hs-1 is directly connected to the router rt-1;
+	#  - host hs-2 is directly connected to the router rt-2.
+	setup_hs 1 1 100
+	setup_hs 2 2 100
+
+	# setup the IPv4 L3 VPN which connects the host hs-1 and host hs-2.
+	setup_vpn_config 1 1 2 2 100  #args: src_host src_router dst_host dst_router tenant
+	setup_vpn_config 2 2 1 1 100
+}
+
+check_hs_connectivity()
+{
+	local hssrc=$1
+	local hsdst=$2
+	local tid=$3
+
+	ip netns exec hs-${hssrc} ping -6 -c 1 -W ${PING_TIMEOUT_SEC} \
+		${IPv6_HS_NETWORK}::${hsdst} >/dev/null 2>&1
+}
+
+check_and_log_hs_connectivity()
+{
+	local hssrc=$1
+	local hsdst=$2
+	local tid=$3
+
+	check_hs_connectivity ${hssrc} ${hsdst} ${tid}
+	log_test $? 0 "Hosts connectivity: hs-${hssrc} -> hs-${hsdst} (tenant ${tid})"
+}
+
+host_tests()
+{
+	log_section "SRv6 VPN connectivity test among hosts in the same tenant"
+
+	check_and_log_hs_connectivity 1 2 100
+	check_and_log_hs_connectivity 2 1 100
+}
+
+router_netfilter_tests()
+{
+	log_section "SRv6 VPN connectivity test with netfilter enabled in routers"
+	setup_rt_netfilter 1
+	setup_rt_netfilter 2
+
+	check_and_log_hs_connectivity 1 2 100
+	check_and_log_hs_connectivity 2 1 100
+}
+
+if [ "$(id -u)" -ne 0 ];then
+	echo "SKIP: Need root privileges"
+	exit $ksft_skip
+fi
+
+if [ ! -x "$(command -v ip)" ]; then
+	echo "SKIP: Could not run test without ip tool"
+	exit $ksft_skip
+fi
+
+cleanup &>/dev/null
+
+setup
+
+host_tests
+router_netfilter_tests
+
+print_log_test_results
+
+cleanup &>/dev/null
+
+exit ${ret}