[PATCH net-next v4 0/4] discard ARP/NDP b/mcast/null announce (poison)

[PATCH net-next v4 0/4] discard ARP/NDP b/mcast/null announce (poison)

[Marc Suñé]

The current ARP and NDP implementations accept announcements with
multicast (broadcast incl.) and null MAC addresses as Sender HW Address
(SHA) in ARP or src/target lladdr in NDP, and updates the cache
for that neighbour.

Multicast (incl. broadcast) and null MAC addresses shall never be
associated with a unicast or a multicast IPv4/6 address (see RFC1812,
section 3.3.2).

ARP/NDP poisioning with a broadcast and certain multicast MAC addresses,
especially when poisoning a Gateway IP, have some undesired implications
compared to an ARP/NDP poisioning with a regular MAC (see commit message
in patch 1 for more information).

Worth mentioning that if an attacker is able to ARP/NDP poison in
a L2 segment, that in itself is probably a bigger security threat
(Man-in-middle etc., see Note2 in patch 1)

Since these MACs should never be announced, this patch series discards/drops
these packets, which prevents broadcast and multicast ARP/NDP poisoning
vectors.

This patchset only modifies the behaviour of the neighbouring subsystem
when processing network packets. Static entries can still be added with
mcast/bcast/null MACs.

v3: https://lore.kernel.org/netdev/cover.1770241104.git.marcdevel@gmail.com/
v2: https://lore.kernel.org/netdev/cover.1769464405.git.marcdevel@gmail.com/
v1: https://lore.kernel.org/netdev/cover.1766349632.git.marcdevel@gmail.com/

Changes since v3
================
  - Respin rebase on top net-next

Changes since v2
================
  - Target net-next instead of net
  - Use mausezahn for patch2 and remove arp_send.c
  - Kept ndisc_send.c for patch 4, as ndisc6 and mausezahn are not valid
    options (see comment)
  - Fixed comment llsrc->lltgt (AI review)
  - Misc fixes: shellcheck, alphabetical order in Makefile

Changes since RFC v1
====================
  - Discard announcements with multicast MAC addresses
  - Check for dev->type == ARPHRD_ETHER instead of HW addrlen in ARP
  - Use !is_valid_ether_addr()
  - Added multicast test coverage and renamed tests accordingly
  - Dropped patch 5 (scapy utils)

Comments
========

On `ndisc_send.c` alternatives, ndisc6 and extending mausezahn were not viable
options. Submitted with `ndisc_send.c`, as preferred by maintainers.

Having said that, I still think Scapy is the best tool for these sort of packet
generation, and can simplify - perhaps at a cost of some test execution time -
selftest creation and maintenance. As also mentioned in
../bpf/generate_udp_fragments.py, it's sort of industry standard, and is widely
used for dataplane functional testing. I've personally used it in several
organizations to functionally test ASICs, NPUs and SW datapaths.

If maintainers are willing to reconsider that, I'd be happy to work on
transitioning the existing selftests (using ndisc6, mausezahn...) towards Scapy.

Marc Suñé (4):
  arp: discard invalid sha addr (b/mcast ARP poison)
  selftests/net: add no ARP b/mcast,null poison test
  neigh: discard invalid lladdr (b/mcast poison)
  selftests/net: add no NDP b/mcast,null poison test

 net/ipv4/arp.c                                |   8 +
 net/ipv6/ndisc.c                              |  16 +
 tools/testing/selftests/net/.gitignore        |   1 +
 tools/testing/selftests/net/Makefile          |   3 +
 .../net/arp_ndisc_no_invalid_sha_poison.sh    | 368 ++++++++++++++++++
 tools/testing/selftests/net/ndisc_send.c      | 198 ++++++++++
 6 files changed, 594 insertions(+)
 create mode 100755 tools/testing/selftests/net/arp_ndisc_no_invalid_sha_poison.sh
 create mode 100644 tools/testing/selftests/net/ndisc_send.c

-- 
2.47.3

[PATCH net-next v4 1/4] arp: discard invalid sha addr (b/mcast ARP poison)

[Marc Suñé]

Prior to this commit, the ARP implementation accepted ARP req/replies
with multicast (including broadcast) and null MAC addresses as Sender
HW Address (SHA), and updated the ARP cache for that neighbour.
Broadcast, multicast and null MAC addresses shall never be associated
with a unicast or a multicast IPv4 address (see RFC1812, section 3.3.2).

ARP poisioning with a broadcast MAC address and certain multicast
addresses, especially when poisoning a Gateway IP, have some undesired
implications compared to an ARP poisioning with a regular MAC (see
Note1).

Worth mentioning that if an attacker is able to ARP poison in
a L2 segment, that in itself is probably a bigger security threat
(Man-in-middle etc., see Note2).

However, since these MACs should never be announced as SHA,
discard/drop ARPs with SHA={b/mcast, null}, which prevents the
broadcast/multicast ARP poisoning vector.

Note1:

After a successful broadcast/multicast ARP poisioning attack:

1. Unicast packets and refresh ("targeted") ARPs sent to or via
   the poisioned IP (e.g. the default GW) are flooded by
   bridges/switches. That is in absence of other security controls.

   Hardware swiches generally have rate-limits to prevent/mitigate
   broadcast storms, since ARPs are usually answered by the CPU.
   Legit unicast packets could be dropped (perf. degradation).

   Most modern NICs implement some form of L2 MAC filtering to early
   discard irrelevant packets. In contrast to an ARP poisoning
   attack with any other MAC, both unicast and ARP ("targeted")
   refresh packets are passed up to the Kernel networking stack
   (for all hosts in the L2 segment).

2. A single forged ARP packet (e.g. for the Gateway IP) can produce
   up to N "targeted" (to broadcast) ARPs, where N is the number of
   hosts in the L2 segment that have an ARP entry for that IP
   (e.g. GW), and some more traffic, since the real host will answer
   to targeted refresh ARPs with their (real) reply.

   This is a relatively low amount of traffic compared to 1).

3. An attacker could use this form of ARP poisoning to discover
   all hosts in a L2 segment in a very short period of time with
   one or few packets.

   By poisoning e.g. the default GW (likely multiple times, to
   avoid races with real gARPs from the GW), all hosts will eventually
   issue refresh "targeted" ARPs for the GW IP with the broadcast MAC
   address as destination. These packets will be flooded in the L2
   segment, revealing the presence of hosts to the attacker.

   For comparison:
     * Passive ARP monitoring: also stealthy, but can take a long
       time or not be possible at all in switches, as most refresh
       ARPs are targeted.
     * ARP req flooding: requires swiping the entire subnet. Noisy
       and easy to detect.
     * ICMP/L4 port scans: similar to the above.

4. In the unlikely case that hosts were to run with
   `/proc/sys/net/ipv4/conf/*/arp_accept=1` (unsafe, and disabled
   by default), poisoning with the broadcast MAC could be used to
   create significantly more broadcast traffic (low-volume
   amplification attack).

   An attacker could send M fake gARP with a number of IP addresses,
   where M is `/proc/sys/net/ipv4/neigh/*/gc_thresh3` (1024 by
   default). This would result in M x R ARPs, where R is the number
   of hosts in L2 segment with `arp_accept=1`, and likely other
   (real) ARP replies coming from the attacked host. This starts to
   get really relevant when R > 512, which is possible in large LANs
   but not very common.

Note2:

However, broadcast ARP poisoning might be subtle and difficult to
spot. These ARP packets appear on the surface as regular broadcast
ARP requests (unless ARP hdr is inspected), traffic continues to
flow uninterrupted (unless broadcast rate-limit in switches kick-in)
and, the next refresh ARP reply (from the GW) or any (valid) gARP
from the GW, will restore the original MAC in the ARP table, making
the traffic flow normally again.

Signed-off-by: Marc Suñé <marcdevel@gmail.com>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
---
 net/ipv4/arp.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/net/ipv4/arp.c b/net/ipv4/arp.c
index c8c3e1713c0e..7dbb3fd5cc8a 100644
--- a/net/ipv4/arp.c
+++ b/net/ipv4/arp.c
@@ -800,6 +800,14 @@ static int arp_process(struct net *net, struct sock *sk, struct sk_buff *skb)
 		goto out_free_skb;
 
 /*
+ *	For Ethernet devices, Multicast/Broadcast and zero MAC addresses should
+ *	never be announced and accepted as sender HW address (RFC1812, 3.3.2).
+ *	Prevents Broadcast/Mcast ARP poisoning attack.
+ */
+	if (dev->type == ARPHRD_ETHER && !is_valid_ether_addr(sha))
+		goto out_free_skb;
+
+ /*
  *     Special case: We must set Frame Relay source Q.922 address
  */
 	if (dev_type == ARPHRD_DLCI)
-- 
2.47.3

[PATCH net-next v4 2/4] selftests/net: add no ARP b/mcast,null poison test

[Marc Suñé]

Add a selftest to test that ARP bcast/mcast/null poisioning checks
are never bypassed.

Signed-off-by: Marc Suñé <marcdevel@gmail.com>
---
 tools/testing/selftests/net/Makefile          |   1 +
 .../net/arp_no_invalid_sha_poision.sh         | 173 ++++++++++++++++++
 2 files changed, 174 insertions(+)
 create mode 100755 tools/testing/selftests/net/arp_no_invalid_sha_poision.sh

diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile
index afdea6d95bde..c6d571bf72be 100644
--- a/tools/testing/selftests/net/Makefile
+++ b/tools/testing/selftests/net/Makefile
@@ -11,6 +11,7 @@ TEST_PROGS := \
 	amt.sh \
 	arp_ndisc_evict_nocarrier.sh \
 	arp_ndisc_untracked_subnets.sh \
+	arp_no_invalid_sha_poision.sh \
 	bareudp.sh \
 	big_tcp.sh \
 	bind_bhash.sh \
diff --git a/tools/testing/selftests/net/arp_no_invalid_sha_poision.sh b/tools/testing/selftests/net/arp_no_invalid_sha_poision.sh
new file mode 100755
index 000000000000..755dd31212c8
--- /dev/null
+++ b/tools/testing/selftests/net/arp_no_invalid_sha_poision.sh
@@ -0,0 +1,173 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# Tests that ARP announcements with Broadcast, Multicast or NULL mac are never
+# accepted
+#
+
+source lib.sh
+
+readonly V4_ADDR0="10.0.10.1"
+readonly V4_ADDR1="10.0.10.2"
+readonly BCAST_MAC="ff:ff:ff:ff:ff:ff"
+readonly MCAST_MAC="01:00:5e:00:00:00"
+readonly NULL_MAC="00:00:00:00:00:00"
+readonly VALID_MAC="02:01:02:03:04:05"
+readonly ARP_REQ="request"
+readonly ARP_REPLY="reply"
+ret=0
+veth1_mac=
+
+setup() {
+	setup_ns PEER_NS
+
+	ip link add name veth0 type veth peer name veth1
+	ip link set dev veth0 up
+	ip link set dev veth1 netns "${PEER_NS}"
+	ip netns exec "${PEER_NS}" ip link set dev veth1 up
+	ip addr add "${V4_ADDR0}"/24 dev veth0
+	ip netns exec "${PEER_NS}" ip addr add "${V4_ADDR1}"/24 dev veth1
+	ip netns exec "${PEER_NS}" ip route add default via "${V4_ADDR0}" dev veth1
+
+	# Raise ARP timers to avoid flakes due to refreshes
+	sysctl -w net.ipv4.neigh.veth0.base_reachable_time=3600 \
+		>/dev/null 2>&1
+	ip netns exec "${PEER_NS}" \
+		sysctl -w net.ipv4.neigh.veth1.gc_stale_time=3600 \
+		>/dev/null 2>&1
+	ip netns exec "${PEER_NS}" \
+		sysctl -w net.ipv4.neigh.veth1.base_reachable_time=3600 \
+		>/dev/null 2>&1
+
+	veth1_mac="$(ip netns exec "${PEER_NS}" ip -j link show veth1 | \
+		jq -r '.[0].address' )"
+}
+
+cleanup() {
+	ip neigh flush dev veth0
+	ip link del veth0
+	cleanup_ns "${PEER_NS}"
+}
+
+# Make sure ARP announcement with invalid MAC is never learnt
+run_no_arp_poisoning() {
+	local l2_dmac="${1}"
+	local tmac="${2}"
+	local op="${3}"
+
+	ret=0
+
+	ip netns exec "${PEER_NS}" ip neigh flush dev veth1 >/dev/null 2>&1
+	ip netns exec "${PEER_NS}" ping -c 1 "${V4_ADDR0}" >/dev/null 2>&1
+
+	# Poison with a valid MAC to ensure injection is working
+	mausezahn "veth0" -q -a "${VALID_MAC}" -b "${BCAST_MAC}" -t arp \
+		  "${op}, sip=${V4_ADDR0}, tip=${V4_ADDR0}, smac=${VALID_MAC}, tmac=${VALID_MAC}"
+
+	neigh=$(ip netns exec "${PEER_NS}" ip neigh show "${V4_ADDR0}" | \
+		grep "${VALID_MAC}")
+	if [ "${neigh}" == "" ]; then
+		echo "ERROR: unable to ARP poision with a valid MAC ${VALID_MAC}"
+		ip netns exec "${PEER_NS}" ip neigh show "${V4_ADDR0}"
+		ret=1
+		return
+	fi
+
+	# Poison with tmac
+	mausezahn "veth0" -q -a "${VALID_MAC}" -b "${l2_dmac}" -t arp \
+		  "${op}, sip=${V4_ADDR0}, tip=${V4_ADDR0}, smac=${tmac}, tmac=${tmac}"
+
+	neigh=$(ip netns exec "${PEER_NS}" ip neigh show "${V4_ADDR0}" | \
+		grep "${tmac}")
+	if [ "${neigh}" != "" ]; then
+		echo "ERROR: ARP entry learnt for ${tmac} announcement."
+		ip netns exec "${PEER_NS}" ip neigh show "${V4_ADDR0}"
+		ret=1
+		return
+	fi
+}
+
+print_test_result() {
+	local msg="${1}"
+	local rc="${2}"
+
+	if [ "${rc}" == 0 ]; then
+		printf "TEST: %-60s  [ OK ]" "${msg}"
+	else
+		printf "TEST: %-60s  [ FAIL ]" "${msg}"
+	fi
+}
+
+run_all_tests() {
+	local results
+
+	setup
+
+	## ARP
+	# Broadcast gARPs
+	msg="1.1  ARP no poisoning dmac=bcast reply sha=bcast"
+	run_no_arp_poisoning "${BCAST_MAC}" "${BCAST_MAC}" "${ARP_REPLY}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="1.2  ARP no poisoning dmac=bcast reply sha=null"
+	run_no_arp_poisoning "${BCAST_MAC}" "${NULL_MAC}" "${ARP_REPLY}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="1.3  ARP no poisoning dmac=bcast req   sha=bcast"
+	run_no_arp_poisoning "${BCAST_MAC}" "${BCAST_MAC}" "${ARP_REQ}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="1.4  ARP no poisoning dmac=bcast req   sha=null"
+	run_no_arp_poisoning "${BCAST_MAC}" "${NULL_MAC}" "${ARP_REQ}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="1.5  ARP no poisoning dmac=bcast req   sha=mcast"
+	run_no_arp_poisoning "${BCAST_MAC}" "${MCAST_MAC}" "${ARP_REQ}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="1.6  ARP no poisoning dmac=bcast reply sha=mcast"
+	run_no_arp_poisoning "${BCAST_MAC}" "${MCAST_MAC}" "${ARP_REPLY}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	# Targeted gARPs
+	msg="1.7  ARP no poisoning dmac=veth0 reply sha=bcast"
+	run_no_arp_poisoning "${veth1_mac}" "${BCAST_MAC}" "${ARP_REPLY}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="1.8  ARP no poisoning dmac=veth0 reply sha=null"
+	run_no_arp_poisoning "${veth1_mac}" "${NULL_MAC}" "${ARP_REPLY}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="1.9  ARP no poisoning dmac=veth0 req   sha=bcast"
+	run_no_arp_poisoning "${veth1_mac}" "${BCAST_MAC}" "${ARP_REQ}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="1.10 ARP no poisoning dmac=veth0 req   sha=null"
+	run_no_arp_poisoning "${veth1_mac}" "${NULL_MAC}" "${ARP_REQ}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="1.11 ARP no poisoning dmac=veth0 req   sha=mcast"
+	run_no_arp_poisoning "${veth1_mac}" "${MCAST_MAC}" "${ARP_REQ}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="1.12 ARP no poisoning dmac=veth0 reply sha=mcast"
+	run_no_arp_poisoning "${veth1_mac}" "${MCAST_MAC}" "${ARP_REPLY}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	cleanup
+
+	printf '%b' "${results}"
+}
+
+if [ "$(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 "${ksft_skip}"
+fi
+
+run_all_tests
+exit "${ret}"
-- 
2.47.3

[PATCH net-next v4 3/4] neigh: discard invalid lladdr (b/mcast poison)

[Marc Suñé]

Prior to this commit, the NDP implementation accepted NDP NS/NA with
the broadcast, multicast and null addresses as src/dst lladdr, and
updated the neighbour cache for that host.

Broadcast, multicast and null MAC addresses shall never be associated
with a unicast or a multicast IPv6 address (see RFC1812, section 3.3.2).

NDP poisioning with a broadcast MAC and certain multicast MAC addresses,
especially when poisoning a Gateway IP, have some undesired implications
compared to an NDP poisioning with a regular MAC (see ARP bcast poison
commit for more details).

Since these MACs should never be announced, discard/drop NDP with
lladdr={bcast, null}, which prevents the broadcast/multicast NDP
poisoning vector.

Signed-off-by: Marc Suñé <marcdevel@gmail.com>
---
 net/ipv6/ndisc.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
index f6a5d8c73af9..8fe215505869 100644
--- a/net/ipv6/ndisc.c
+++ b/net/ipv6/ndisc.c
@@ -830,6 +830,14 @@ static enum skb_drop_reason ndisc_recv_ns(struct sk_buff *skb)
 			return reason;
 		}
 
+		/*
+		 * Broadcast/Multicast and zero MAC addresses should
+		 * never be announced and accepted as llsrc address (prevent
+		 * NDP B/MCAST MAC poisoning attack).
+		 */
+		if (dev->type == ARPHRD_ETHER && !is_valid_ether_addr(lladdr))
+			return reason;
+
 		/* RFC2461 7.1.1:
 		 *	If the IP source address is the unspecified address,
 		 *	there MUST NOT be source link-layer address option
@@ -1033,6 +1041,14 @@ static enum skb_drop_reason ndisc_recv_na(struct sk_buff *skb)
 			net_dbg_ratelimited("NA: invalid link-layer address length\n");
 			return reason;
 		}
+
+		/*
+		 * Broadcast/Multicast and zero MAC addresses should
+		 * never be announced and accepted as lltgt address (prevent
+		 * NDP B/MCAST MAC poisoning attack).
+		 */
+		if (dev->type == ARPHRD_ETHER && !is_valid_ether_addr(lladdr))
+			return reason;
 	}
 	ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1);
 	if (ifp) {
-- 
2.47.3

[PATCH net-next v4 4/4] selftests/net: add no NDP b/mcast,null poison test

[Marc Suñé]

Add a selftest to test that NDP bcast/mcast/null poisioning checks are
never bypassed.

Signed-off-by: Marc Suñé <marcdevel@gmail.com>
---
 tools/testing/selftests/net/.gitignore        |   1 +
 tools/testing/selftests/net/Makefile          |   2 +
 .../net/arp_ndisc_no_invalid_sha_poison.sh    | 368 ++++++++++++++++++
 .../net/arp_no_invalid_sha_poision.sh         | 173 --------
 tools/testing/selftests/net/ndisc_send.c      | 198 ++++++++++
 5 files changed, 569 insertions(+), 173 deletions(-)
 create mode 100755 tools/testing/selftests/net/arp_ndisc_no_invalid_sha_poison.sh
 delete mode 100755 tools/testing/selftests/net/arp_no_invalid_sha_poision.sh
 create mode 100644 tools/testing/selftests/net/ndisc_send.c

diff --git a/tools/testing/selftests/net/.gitignore b/tools/testing/selftests/net/.gitignore
index 97ad4d551d44..3e703b31a8e1 100644
--- a/tools/testing/selftests/net/.gitignore
+++ b/tools/testing/selftests/net/.gitignore
@@ -18,6 +18,7 @@ ipv6_flowlabel_mgr
 ipv6_fragmentation
 log.txt
 msg_zerocopy
+ndisc_send
 netlink-dumps
 nettest
 proc_net_pktgen
diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile
index c6d571bf72be..a8661191a78b 100644
--- a/tools/testing/selftests/net/Makefile
+++ b/tools/testing/selftests/net/Makefile
@@ -10,6 +10,7 @@ TEST_PROGS := \
 	altnames.sh \
 	amt.sh \
 	arp_ndisc_evict_nocarrier.sh \
+	arp_ndisc_no_invalid_sha_poison.sh \
 	arp_ndisc_untracked_subnets.sh \
 	arp_no_invalid_sha_poision.sh \
 	bareudp.sh \
@@ -171,6 +172,7 @@ TEST_GEN_PROGS := \
 	epoll_busy_poll \
 	icmp_rfc4884 \
 	ipv6_fragmentation \
+	ndisc_send \
 	proc_net_pktgen \
 	reuseaddr_conflict \
 	reuseport_bpf \
diff --git a/tools/testing/selftests/net/arp_ndisc_no_invalid_sha_poison.sh b/tools/testing/selftests/net/arp_ndisc_no_invalid_sha_poison.sh
new file mode 100755
index 000000000000..ad91eac18c89
--- /dev/null
+++ b/tools/testing/selftests/net/arp_ndisc_no_invalid_sha_poison.sh
@@ -0,0 +1,368 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# Tests that ARP announcements with Broadcast or NULL mac are never
+# accepted
+#
+
+source lib.sh
+
+readonly V4_ADDR0="10.0.10.1"
+readonly V6_ADDR0="fd00:1::1"
+readonly V4_ADDR1="10.0.10.2"
+readonly V6_ADDR1="fd00:1::2"
+readonly V6_ALL_NODES="ff02::1"
+readonly V6_SOL_NODE1="ff02::1:ff00:0002"
+readonly BCAST_MAC="ff:ff:ff:ff:ff:ff"
+readonly MCAST_MAC="01:00:5e:00:00:00"
+readonly NULL_MAC="00:00:00:00:00:00"
+readonly VALID_MAC="02:01:02:03:04:05"
+readonly V6_ALL_NODE_MAC="33:33:FF:00:00:01"
+readonly V6_SOL_NODE_MAC1="33:33:FF:00:00:02"
+readonly NS=135
+readonly NA=136
+readonly ARP_REQ=request
+readonly ARP_REPLY=reply
+ret=0
+veth0_ifindex=0
+veth1_mac=
+
+setup() {
+	setup_ns PEER_NS
+
+	ip link add name veth0 type veth peer name veth1
+	ip link set dev veth0 up
+	ip link set dev veth1 netns "${PEER_NS}"
+	ip netns exec "${PEER_NS}" ip link set dev veth1 up
+	ip addr add "${V4_ADDR0}"/24 dev veth0
+	ip addr add "${V6_ADDR0}"/64 dev veth0
+	ip netns exec "${PEER_NS}" ip addr add "${V4_ADDR1}"/24 dev veth1
+	ip netns exec "${PEER_NS}" ip route add default via "${V4_ADDR0}" dev veth1
+
+	ip netns exec "${PEER_NS}" ip addr add "${V6_ADDR1}"/64 dev veth1
+	ip netns exec "${PEER_NS}" ip route add default via "${V6_ADDR0}" dev veth1
+
+	# Raise ARP timers to avoid flakes due to refreshes
+	sysctl -w net.ipv4.neigh.veth0.base_reachable_time=3600 \
+		>/dev/null 2>&1
+	ip netns exec "${PEER_NS}" \
+		sysctl -w net.ipv4.neigh.veth1.gc_stale_time=3600 \
+		>/dev/null 2>&1
+	ip netns exec "${PEER_NS}" \
+		sysctl -w net.ipv4.neigh.veth1.base_reachable_time=3600 \
+		>/dev/null 2>&1
+
+	veth0_ifindex=$(ip -j link show veth0 | jq -r '.[0].ifindex')
+	veth1_mac="$(ip netns exec "${PEER_NS}" ip -j link show veth1 | \
+		jq -r '.[0].address' )"
+}
+
+cleanup() {
+	ip neigh flush dev veth0
+	ip link del veth0
+	cleanup_ns "${PEER_NS}"
+}
+
+# Make sure ARP announcement with invalid MAC is never learnt
+run_no_arp_poisoning() {
+	local l2_dmac="${1}"
+	local tmac="${2}"
+	local op="${3}"
+
+	ret=0
+
+	ip netns exec "${PEER_NS}" ip neigh flush dev veth1 >/dev/null 2>&1
+	ip netns exec "${PEER_NS}" ping -c 1 "${V4_ADDR0}" >/dev/null 2>&1
+
+	# Poison with a valid MAC to ensure injection is working
+	mausezahn "veth0" -q -a "${VALID_MAC}" -b "${BCAST_MAC}" -t arp \
+		  "${op}, sip=${V4_ADDR0}, tip=${V4_ADDR0}, smac=${VALID_MAC}, tmac=${VALID_MAC}"
+
+	neigh=$(ip netns exec "${PEER_NS}" ip neigh show "${V4_ADDR0}" | \
+		grep "${VALID_MAC}")
+	if [ "${neigh}" == "" ]; then
+		echo "ERROR: unable to ARP poision with a valid MAC ${VALID_MAC}"
+		ip netns exec "${PEER_NS}" ip neigh show "${V4_ADDR0}"
+		ret=1
+		return
+	fi
+
+	# Poison with tmac
+	mausezahn "veth0" -q -a "${VALID_MAC}" -b "${l2_dmac}" -t arp \
+		  "${op}, sip=${V4_ADDR0}, tip=${V4_ADDR0}, smac=${tmac}, tmac=${tmac}"
+
+
+	neigh=$(ip netns exec "${PEER_NS}" ip neigh show "${V4_ADDR0}" | \
+		grep "${tmac}")
+	if [ "${neigh}" != "" ]; then
+		echo "ERROR: ARP entry learnt for ${tmac} announcement."
+		ip netns exec "${PEER_NS}" ip neigh show "${V4_ADDR0}"
+		ret=1
+		return
+	fi
+}
+
+# Make sure NDP announcement with invalid MAC is never learnt
+run_no_ndp_poisoning() {
+	local l2_dmac="${1}"
+	local dst_ip="${2}"
+	local op="${3}"
+	local tip="${V6_ADDR0}"
+	local tmac="${4}"
+
+	if [ "${op}" == "${NS}" ]; then
+		tip="${V6_ADDR1}"
+	fi
+
+	ret=0
+
+	ip netns exec "${PEER_NS}" ip -6 neigh flush dev veth1 >/dev/null 2>&1
+	ip netns exec "${PEER_NS}" ping -c 1 "${V6_ADDR0}" >/dev/null 2>&1
+
+	# Poison with a valid MAC to ensure injection is working
+	./ndisc_send "${veth0_ifindex}" "${l2_dmac}" "${VALID_MAC}" "${dst_ip}" \
+		"${V6_ADDR0}" "${tip}" "${op}" "${VALID_MAC}"
+	neigh=$(ip netns exec "${PEER_NS}" ip neigh show "${V6_ADDR0}" | \
+		grep "${VALID_MAC}")
+	if [ "${neigh}" == "" ]; then
+		echo "ERROR: unable to NDP poision with a valid MAC ${VALID_MAC}"
+		ip netns exec "${PEER_NS}" ip neigh show "${V6_ADDR0}"
+		ret=1
+		return
+	fi
+
+	# Poison with tmac
+	./ndisc_send "${veth0_ifindex}" "${l2_dmac}" "${VALID_MAC}" "${dst_ip}" \
+		"${V6_ADDR0}" "${tip}" "${op}" "${tmac}"
+	neigh=$(ip netns exec "${PEER_NS}" ip neigh show "${V6_ADDR0}" | \
+		grep "${tmac}")
+	if [ "${neigh}" != "" ]; then
+		echo "ERROR: NDP entry learnt for ${tmac} announcement."
+		ip netns exec "${PEER_NS}" ip neigh show "${V6_ADDR0}"
+		ret=1
+		return
+	fi
+}
+
+print_test_result() {
+	local msg="${1}"
+	local rc="${2}"
+
+	if [ "${rc}" == 0 ]; then
+		printf "TEST: %-60s  [ OK ]" "${msg}"
+	else
+		printf "TEST: %-60s  [ FAIL ]" "${msg}"
+	fi
+}
+
+run_all_tests() {
+	local results
+
+	setup
+
+	## ARP
+	# Broadcast gARPs
+	msg="1.1  ARP no poisoning dmac=bcast reply sha=bcast"
+	run_no_arp_poisoning "${BCAST_MAC}" "${BCAST_MAC}" "${ARP_REPLY}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="1.2  ARP no poisoning dmac=bcast reply sha=null"
+	run_no_arp_poisoning "${BCAST_MAC}" "${NULL_MAC}" "${ARP_REPLY}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="1.3  ARP no poisoning dmac=bcast req   sha=bcast"
+	run_no_arp_poisoning "${BCAST_MAC}" "${BCAST_MAC}" "${ARP_REQ}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="1.4  ARP no poisoning dmac=bcast req   sha=null"
+	run_no_arp_poisoning "${BCAST_MAC}" "${NULL_MAC}" "${ARP_REQ}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="1.5  ARP no poisoning dmac=bcast req   sha=mcast"
+	run_no_arp_poisoning "${BCAST_MAC}" "${MCAST_MAC}" "${ARP_REQ}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="1.6  ARP no poisoning dmac=bcast reply sha=mcast"
+	run_no_arp_poisoning "${BCAST_MAC}" "${MCAST_MAC}" "${ARP_REPLY}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	# Targeted gARPs
+	msg="1.7  ARP no poisoning dmac=veth0 reply sha=bcast"
+	run_no_arp_poisoning "${veth1_mac}" "${BCAST_MAC}" "${ARP_REPLY}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="1.8  ARP no poisoning dmac=veth0 reply sha=null"
+	run_no_arp_poisoning "${veth1_mac}" "${NULL_MAC}" "${ARP_REPLY}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="1.9  ARP no poisoning dmac=veth0 req   sha=bcast"
+	run_no_arp_poisoning "${veth1_mac}" "${BCAST_MAC}" "${ARP_REQ}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="1.10 ARP no poisoning dmac=veth0 req   sha=null"
+	run_no_arp_poisoning "${veth1_mac}" "${NULL_MAC}" "${ARP_REQ}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="1.11 ARP no poisoning dmac=veth0 req   sha=mcast"
+	run_no_arp_poisoning "${veth1_mac}" "${MCAST_MAC}" "${ARP_REQ}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="1.12 ARP no poisoning dmac=veth0 reply sha=mcast"
+	run_no_arp_poisoning "${veth1_mac}" "${MCAST_MAC}" "${ARP_REPLY}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	### NDP
+	## NA
+	# Broadcast / All node MAC, all-node IP announcements
+	msg="2.1  NDP no poisoning dmac=bcast   all_nodes na lladdr=bcast"
+	run_no_ndp_poisoning "${BCAST_MAC}" "${V6_ALL_NODES}" "${NA}" "${BCAST_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="2.2  NDP no poisoning dmac=bcast   all_nodes na lladdr=null"
+	run_no_ndp_poisoning "${BCAST_MAC}" "${V6_ALL_NODES}" "${NA}" "${NULL_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="2.3  NDP no poisoning dmac=allnode all_nodes na lladdr=bcast"
+	run_no_ndp_poisoning "${V6_ALL_NODE_MAC}" "${V6_ALL_NODES}" "${NA}" "${BCAST_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="2.4  NDP no poisoning dmac=allnode all_nodes na lladdr=null"
+	run_no_ndp_poisoning "${V6_ALL_NODE_MAC}" "${V6_ALL_NODES}" "${NA}" "${NULL_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="2.5  NDP no poisoning dmac=bcast   all_nodes na lladdr=bcast"
+	run_no_ndp_poisoning "${BCAST_MAC}" "${V6_ALL_NODES}" "${NA}" "${BCAST_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="2.6  NDP no poisoning dmac=bcast   all_nodes na lladdr=null"
+	run_no_ndp_poisoning "${BCAST_MAC}" "${V6_ALL_NODES}" "${NA}" "${NULL_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="2.7  NDP no poisoning dmac=allnode all_nodes na lladdr=bcast"
+	run_no_ndp_poisoning "${V6_ALL_NODE_MAC}" "${V6_ALL_NODES}" "${NA}" "${BCAST_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="2.8  NDP no poisoning dmac=allnode all_nodes na lladdr=null"
+	run_no_ndp_poisoning "${V6_ALL_NODE_MAC}" "${V6_ALL_NODES}" "${NA}" "${NULL_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	# Broadcast / All node MAC, Targeted IP announce
+	msg="2.9  NDP no poisoning dmac=bcast   targeted  na lladdr=bcast"
+	run_no_ndp_poisoning "${BCAST_MAC}" "${V6_ADDR1}" "${NA}" "${BCAST_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="2.10 NDP no poisoning dmac=bcast   targeted  na lladdr=null"
+	run_no_ndp_poisoning "${BCAST_MAC}" "${V6_ADDR1}" "${NA}" "${NULL_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="2.11 NDP no poisoning dmac=allnode targeted  na lladdr=bcast"
+	run_no_ndp_poisoning "${V6_ALL_NODE_MAC}" "${V6_ADDR1}" "${NA}" "${BCAST_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="2.12 NDP no poisoning dmac=allnode targeted  na lladdr=null"
+	run_no_ndp_poisoning "${V6_ALL_NODE_MAC}" "${V6_ADDR1}" "${NA}" "${NULL_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="2.13 NDP no poisoning dmac=bcast   targeted  na lladdr=bcast"
+	run_no_ndp_poisoning "${BCAST_MAC}" "${V6_ADDR1}" "${NA}" "${BCAST_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="2.14 NDP no poisoning dmac=bcast   targeted  na lladdr=null"
+	run_no_ndp_poisoning "${BCAST_MAC}" "${V6_ADDR1}" "${NA}" "${NULL_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="2.15 NDP no poisoning dmac=allnode targeted  na lladdr=bcast"
+	run_no_ndp_poisoning "${V6_ALL_NODE_MAC}" "${V6_ADDR1}" "${NA}" "${BCAST_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="2.16 NDP no poisoning dmac=allnode targeted  na lladdr=null"
+	run_no_ndp_poisoning "${V6_ALL_NODE_MAC}" "${V6_ADDR1}" "${NA}" "${NULL_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	# Targeted MAC, Targeted IP announce
+	msg="2.17 NDP no poisoning dmac=veth1   targeted  na lladdr=bcast"
+	run_no_ndp_poisoning "${veth1_mac}" "${V6_ADDR1}" "${NA}" "${BCAST_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="2.18 NDP no poisoning dmac=veth1   targeted  na lladdr=null"
+	run_no_ndp_poisoning "${veth1_mac}" "${V6_ADDR1}" "${NA}" "${NULL_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	# Poison with MCAST mac
+	msg="2.19 NDP no poisoning dmac=allnode all_nodes na lladdr=mcast"
+	run_no_ndp_poisoning "${V6_ALL_NODE_MAC}" "${V6_ALL_NODES}" "${NA}" "${MCAST_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+	msg="2.20 NDP no poisoning dmac=veth1   targeted  na lladdr=mcast"
+	run_no_ndp_poisoning "${veth1_mac}" "${V6_ADDR1}" "${NA}" "${MCAST_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	## NS
+	# Broadcast / SolNode node MAC, SolNode IP solic
+	msg="2.21 NDP no poisoning dmac=bcast   solnode   ns lladdr=bcast"
+	run_no_ndp_poisoning "${BCAST_MAC}" "${V6_SOL_NODE1}" "${NS}" "${BCAST_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="2.22 NDP no poisoning dmac=bcast   solnode   ns lladdr=null"
+	run_no_ndp_poisoning "${BCAST_MAC}" "${V6_SOL_NODE1}" "${NS}" "${NULL_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="2.23 NDP no poisoning dmac=solnode solnode   ns lladdr=bcast"
+	run_no_ndp_poisoning "${V6_SOL_NODE_MAC1}" "${V6_SOL_NODE1}" "${NS}" "${BCAST_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="2.24 NDP no poisoning dmac=solnode solnode   ns lladdr=null"
+	run_no_ndp_poisoning "${V6_SOL_NODE_MAC1}" "${V6_SOL_NODE1}" "${NS}" "${NULL_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	# Broadcast / SolNode node MAC, target IP solic
+	msg="2.25 NDP no poisoning dmac=bcast   target    ns lladdr=bcast"
+	run_no_ndp_poisoning "${BCAST_MAC}" "${V6_ADDR1}" "${NS}" "${BCAST_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="2.26 NDP no poisoning dmac=bcast   target    ns lladdr=null"
+	run_no_ndp_poisoning "${BCAST_MAC}" "${V6_ADDR1}" "${NS}" "${NULL_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="2.27 NDP no poisoning dmac=solnode target    ns lladdr=bcast"
+	run_no_ndp_poisoning "${V6_SOL_NODE_MAC1}" "${V6_ADDR1}" "${NS}" "${BCAST_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="2.28 NDP no poisoning dmac=solnode target    ns lladdr=null"
+	run_no_ndp_poisoning "${V6_SOL_NODE_MAC1}" "${V6_ADDR1}" "${NS}" "${NULL_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	# Targeted MAC, Targeted IP solic
+	msg="2.29 NDP no poisoning dmac=veth1   target    ns lladdr=bcast"
+	run_no_ndp_poisoning "${veth1_mac}" "${V6_ADDR1}" "${NS}" "${BCAST_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="2.30 NDP no poisoning dmac=veth1   target    ns lladdr=null"
+	run_no_ndp_poisoning "${veth1_mac}" "${V6_ADDR1}" "${NS}" "${NULL_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	# Poison with MCAST mac
+	msg="2.31 NDP no poisoning dmac=solnode solnode   ns lladdr=mcast"
+	run_no_ndp_poisoning "${V6_SOL_NODE_MAC1}" "${V6_SOL_NODE1}" "${NS}" "${MCAST_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	msg="2.32 NDP no poisoning dmac=veth1   target    ns lladdr=mcast"
+	run_no_ndp_poisoning "${veth1_mac}" "${V6_ADDR1}" "${NS}" "${MCAST_MAC}"
+	results+="$(print_test_result "${msg}" "${ret}")\n"
+
+	cleanup
+
+	printf '%b' "${results}"
+}
+
+if [ "$(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 "${ksft_skip}"
+fi
+
+run_all_tests
+exit "${ret}"
diff --git a/tools/testing/selftests/net/arp_no_invalid_sha_poision.sh b/tools/testing/selftests/net/arp_no_invalid_sha_poision.sh
deleted file mode 100755
index 755dd31212c8..000000000000
--- a/tools/testing/selftests/net/arp_no_invalid_sha_poision.sh
+++ /dev/null
@@ -1,173 +0,0 @@
-#!/bin/bash
-# SPDX-License-Identifier: GPL-2.0
-#
-# Tests that ARP announcements with Broadcast, Multicast or NULL mac are never
-# accepted
-#
-
-source lib.sh
-
-readonly V4_ADDR0="10.0.10.1"
-readonly V4_ADDR1="10.0.10.2"
-readonly BCAST_MAC="ff:ff:ff:ff:ff:ff"
-readonly MCAST_MAC="01:00:5e:00:00:00"
-readonly NULL_MAC="00:00:00:00:00:00"
-readonly VALID_MAC="02:01:02:03:04:05"
-readonly ARP_REQ="request"
-readonly ARP_REPLY="reply"
-ret=0
-veth1_mac=
-
-setup() {
-	setup_ns PEER_NS
-
-	ip link add name veth0 type veth peer name veth1
-	ip link set dev veth0 up
-	ip link set dev veth1 netns "${PEER_NS}"
-	ip netns exec "${PEER_NS}" ip link set dev veth1 up
-	ip addr add "${V4_ADDR0}"/24 dev veth0
-	ip netns exec "${PEER_NS}" ip addr add "${V4_ADDR1}"/24 dev veth1
-	ip netns exec "${PEER_NS}" ip route add default via "${V4_ADDR0}" dev veth1
-
-	# Raise ARP timers to avoid flakes due to refreshes
-	sysctl -w net.ipv4.neigh.veth0.base_reachable_time=3600 \
-		>/dev/null 2>&1
-	ip netns exec "${PEER_NS}" \
-		sysctl -w net.ipv4.neigh.veth1.gc_stale_time=3600 \
-		>/dev/null 2>&1
-	ip netns exec "${PEER_NS}" \
-		sysctl -w net.ipv4.neigh.veth1.base_reachable_time=3600 \
-		>/dev/null 2>&1
-
-	veth1_mac="$(ip netns exec "${PEER_NS}" ip -j link show veth1 | \
-		jq -r '.[0].address' )"
-}
-
-cleanup() {
-	ip neigh flush dev veth0
-	ip link del veth0
-	cleanup_ns "${PEER_NS}"
-}
-
-# Make sure ARP announcement with invalid MAC is never learnt
-run_no_arp_poisoning() {
-	local l2_dmac="${1}"
-	local tmac="${2}"
-	local op="${3}"
-
-	ret=0
-
-	ip netns exec "${PEER_NS}" ip neigh flush dev veth1 >/dev/null 2>&1
-	ip netns exec "${PEER_NS}" ping -c 1 "${V4_ADDR0}" >/dev/null 2>&1
-
-	# Poison with a valid MAC to ensure injection is working
-	mausezahn "veth0" -q -a "${VALID_MAC}" -b "${BCAST_MAC}" -t arp \
-		  "${op}, sip=${V4_ADDR0}, tip=${V4_ADDR0}, smac=${VALID_MAC}, tmac=${VALID_MAC}"
-
-	neigh=$(ip netns exec "${PEER_NS}" ip neigh show "${V4_ADDR0}" | \
-		grep "${VALID_MAC}")
-	if [ "${neigh}" == "" ]; then
-		echo "ERROR: unable to ARP poision with a valid MAC ${VALID_MAC}"
-		ip netns exec "${PEER_NS}" ip neigh show "${V4_ADDR0}"
-		ret=1
-		return
-	fi
-
-	# Poison with tmac
-	mausezahn "veth0" -q -a "${VALID_MAC}" -b "${l2_dmac}" -t arp \
-		  "${op}, sip=${V4_ADDR0}, tip=${V4_ADDR0}, smac=${tmac}, tmac=${tmac}"
-
-	neigh=$(ip netns exec "${PEER_NS}" ip neigh show "${V4_ADDR0}" | \
-		grep "${tmac}")
-	if [ "${neigh}" != "" ]; then
-		echo "ERROR: ARP entry learnt for ${tmac} announcement."
-		ip netns exec "${PEER_NS}" ip neigh show "${V4_ADDR0}"
-		ret=1
-		return
-	fi
-}
-
-print_test_result() {
-	local msg="${1}"
-	local rc="${2}"
-
-	if [ "${rc}" == 0 ]; then
-		printf "TEST: %-60s  [ OK ]" "${msg}"
-	else
-		printf "TEST: %-60s  [ FAIL ]" "${msg}"
-	fi
-}
-
-run_all_tests() {
-	local results
-
-	setup
-
-	## ARP
-	# Broadcast gARPs
-	msg="1.1  ARP no poisoning dmac=bcast reply sha=bcast"
-	run_no_arp_poisoning "${BCAST_MAC}" "${BCAST_MAC}" "${ARP_REPLY}"
-	results+="$(print_test_result "${msg}" "${ret}")\n"
-
-	msg="1.2  ARP no poisoning dmac=bcast reply sha=null"
-	run_no_arp_poisoning "${BCAST_MAC}" "${NULL_MAC}" "${ARP_REPLY}"
-	results+="$(print_test_result "${msg}" "${ret}")\n"
-
-	msg="1.3  ARP no poisoning dmac=bcast req   sha=bcast"
-	run_no_arp_poisoning "${BCAST_MAC}" "${BCAST_MAC}" "${ARP_REQ}"
-	results+="$(print_test_result "${msg}" "${ret}")\n"
-
-	msg="1.4  ARP no poisoning dmac=bcast req   sha=null"
-	run_no_arp_poisoning "${BCAST_MAC}" "${NULL_MAC}" "${ARP_REQ}"
-	results+="$(print_test_result "${msg}" "${ret}")\n"
-
-	msg="1.5  ARP no poisoning dmac=bcast req   sha=mcast"
-	run_no_arp_poisoning "${BCAST_MAC}" "${MCAST_MAC}" "${ARP_REQ}"
-	results+="$(print_test_result "${msg}" "${ret}")\n"
-
-	msg="1.6  ARP no poisoning dmac=bcast reply sha=mcast"
-	run_no_arp_poisoning "${BCAST_MAC}" "${MCAST_MAC}" "${ARP_REPLY}"
-	results+="$(print_test_result "${msg}" "${ret}")\n"
-
-	# Targeted gARPs
-	msg="1.7  ARP no poisoning dmac=veth0 reply sha=bcast"
-	run_no_arp_poisoning "${veth1_mac}" "${BCAST_MAC}" "${ARP_REPLY}"
-	results+="$(print_test_result "${msg}" "${ret}")\n"
-
-	msg="1.8  ARP no poisoning dmac=veth0 reply sha=null"
-	run_no_arp_poisoning "${veth1_mac}" "${NULL_MAC}" "${ARP_REPLY}"
-	results+="$(print_test_result "${msg}" "${ret}")\n"
-
-	msg="1.9  ARP no poisoning dmac=veth0 req   sha=bcast"
-	run_no_arp_poisoning "${veth1_mac}" "${BCAST_MAC}" "${ARP_REQ}"
-	results+="$(print_test_result "${msg}" "${ret}")\n"
-
-	msg="1.10 ARP no poisoning dmac=veth0 req   sha=null"
-	run_no_arp_poisoning "${veth1_mac}" "${NULL_MAC}" "${ARP_REQ}"
-	results+="$(print_test_result "${msg}" "${ret}")\n"
-
-	msg="1.11 ARP no poisoning dmac=veth0 req   sha=mcast"
-	run_no_arp_poisoning "${veth1_mac}" "${MCAST_MAC}" "${ARP_REQ}"
-	results+="$(print_test_result "${msg}" "${ret}")\n"
-
-	msg="1.12 ARP no poisoning dmac=veth0 reply sha=mcast"
-	run_no_arp_poisoning "${veth1_mac}" "${MCAST_MAC}" "${ARP_REPLY}"
-	results+="$(print_test_result "${msg}" "${ret}")\n"
-
-	cleanup
-
-	printf '%b' "${results}"
-}
-
-if [ "$(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 "${ksft_skip}"
-fi
-
-run_all_tests
-exit "${ret}"
diff --git a/tools/testing/selftests/net/ndisc_send.c b/tools/testing/selftests/net/ndisc_send.c
new file mode 100644
index 000000000000..4f226221d079
--- /dev/null
+++ b/tools/testing/selftests/net/ndisc_send.c
@@ -0,0 +1,198 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <sys/socket.h>
+#include <inttypes.h>
+#include <netinet/ether.h>
+#include <arpa/inet.h>
+
+#include <linux/if_packet.h>
+#include <linux/if_ether.h>
+#include <linux/ipv6.h>
+#include <linux/icmpv6.h>
+
+#define ICMPV6_ND_NS 135
+#define ICMPV6_ND_NA 136
+#define ICMPV6_ND_SLLADR 1
+#define ICMPV6_ND_TLLADR 2
+
+#ifndef __noinline
+#define __noinline __attribute__((noinline))
+#endif
+#ifndef __packed
+#define __packed __attribute__((packed))
+#endif
+
+struct icmp6_pseudohdr {
+	struct in6_addr saddr;
+	struct in6_addr daddr;
+	uint32_t plen;
+	uint8_t zero[3];
+	uint8_t next;
+};
+
+struct ndisc_pkt {
+	struct ethhdr eth;
+	struct ipv6hdr ip6;
+	struct ndp_hdrs {
+		struct icmp6hdr hdr;
+		struct in6_addr target;
+
+		uint8_t opt_type;
+		uint8_t opt_len;
+		uint8_t opt_mac[ETH_ALEN];
+	} __packed ndp;
+} __packed;
+
+__noinline uint32_t csum_add(void *buf, int len, uint32_t sum)
+{
+	uint16_t *p = (uint16_t *)buf;
+
+	while (len > 1) {
+		sum += *p++;
+		len -= 2;
+	}
+
+	if (len)
+		sum += *(uint8_t *)p;
+
+	return sum;
+}
+
+static uint16_t csum_fold(uint32_t sum)
+{
+	return ~((sum & 0xffff) + (sum >> 16)) ? : 0xffff;
+}
+
+int parse_opts(int argc, char **argv, int *ifindex, struct ndisc_pkt *pkt)
+{
+	struct ether_addr *mac;
+	uint16_t op;
+	struct icmp6_pseudohdr ph = {0};
+	uint32_t sum = 0;
+
+	if (argc != 9) {
+		fprintf(stderr, "Usage: %s <iface> <mac_dst> <mac_src> <dst_ip> <src_ip> <target_ip> <op> <lladr>\n",
+			argv[0]);
+		return -1;
+	}
+
+	*ifindex = atoi(argv[1]);
+	mac = ether_aton(argv[2]);
+	if (!mac) {
+		fprintf(stderr, "Unable to parse mac_dst from '%s'\n", argv[1]);
+		return -1;
+	}
+
+	/* Ethernet */
+	memcpy(pkt->eth.h_dest, mac, ETH_ALEN);
+	mac = ether_aton(argv[3]);
+	if (!mac) {
+		fprintf(stderr, "Unable to parse mac_src from '%s'\n", argv[2]);
+		return -1;
+	}
+	memcpy(pkt->eth.h_source, mac, ETH_ALEN);
+	pkt->eth.h_proto = htons(ETH_P_IPV6);
+
+	/* IPv6 */
+	pkt->ip6.version = 6;
+	pkt->ip6.nexthdr = IPPROTO_ICMPV6;
+	pkt->ip6.hop_limit = 255;
+
+	if (inet_pton(AF_INET6, argv[4], &pkt->ip6.daddr) != 1) {
+		fprintf(stderr, "Unable to parse src_ip from '%s'\n", argv[4]);
+		return -1;
+	}
+	if (inet_pton(AF_INET6, argv[5], &pkt->ip6.saddr) != 1) {
+		fprintf(stderr, "Unable to parse src_ip from '%s'\n", argv[5]);
+		return -1;
+	}
+
+	/* ICMPv6 */
+	op = atoi(argv[7]);
+	if (op != ICMPV6_ND_NS && op != ICMPV6_ND_NA) {
+		fprintf(stderr, "Invalid ICMPv6 op %d\n", op);
+		return -1;
+	}
+
+	pkt->ndp.hdr.icmp6_type = op;
+	pkt->ndp.hdr.icmp6_code = 0;
+
+	if (inet_pton(AF_INET6, argv[6], &pkt->ndp.target) != 1) {
+		fprintf(stderr, "Unable to parse target_ip from '%s'\n",
+			argv[6]);
+		return -1;
+	}
+
+	/* Target/Source Link-Layer Address */
+	if (op == ICMPV6_ND_NS) {
+		pkt->ndp.opt_type = ICMPV6_ND_SLLADR;
+	} else {
+		pkt->ndp.opt_type = ICMPV6_ND_TLLADR;
+		pkt->ndp.hdr.icmp6_override = 1;
+	}
+	pkt->ndp.opt_len = 1;
+
+	mac = ether_aton(argv[8]);
+	if (!mac) {
+		fprintf(stderr, "Invalid lladdr %s\n", argv[8]);
+		return -1;
+	}
+
+	memcpy(pkt->ndp.opt_mac, mac, ETH_ALEN);
+
+	pkt->ip6.payload_len = htons(sizeof(pkt->ndp));
+
+	/* Pseudoheader */
+	ph.saddr = pkt->ip6.saddr;
+	ph.daddr = pkt->ip6.daddr;
+	ph.plen = htonl(sizeof(pkt->ndp));
+	ph.next = IPPROTO_ICMPV6;
+
+	sum = csum_add(&ph, sizeof(ph), 0);
+	sum = csum_add(&pkt->ndp, sizeof(pkt->ndp), sum);
+
+	pkt->ndp.hdr.icmp6_cksum = csum_fold(sum);
+
+	return 0;
+}
+
+int main(int argc, char **argv)
+{
+	int rc, fd;
+	struct sockaddr_ll bind_addr = {0};
+	int ifindex;
+	struct ndisc_pkt pkt = {0};
+
+	if (parse_opts(argc, argv, &ifindex, &pkt) < 0)
+		return -1;
+
+	fd = socket(AF_PACKET, SOCK_RAW, htons(ETH_P_ALL));
+	if (fd < 0) {
+		fprintf(stderr, "Unable to open raw socket(%d). Need root privileges?\n",
+			fd);
+		return 1;
+	}
+
+	bind_addr.sll_family   = AF_PACKET;
+	bind_addr.sll_protocol = htons(ETH_P_ALL);
+	bind_addr.sll_ifindex  = ifindex;
+
+	rc = bind(fd, (struct sockaddr *)&bind_addr, sizeof(bind_addr));
+	if (rc < 0) {
+		fprintf(stderr, "Unable to bind raw socket(%d). Invalid iface '%d'?\n",
+			rc, ifindex);
+		return 1;
+	}
+
+	rc = send(fd, &pkt, sizeof(pkt), 0);
+	if (rc < 0) {
+		fprintf(stderr, "Unable to send packet: %d\n", rc);
+		return 1;
+	}
+
+	return 0;
+}
-- 
2.47.3

Re: [PATCH net-next v4 2/4] selftests/net: add no ARP b/mcast,null poison test

[Jakub Kicinski]

On Sat,  7 Feb 2026 21:40:34 +0100 Marc Suñé wrote:
> diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile
> index afdea6d95bde..c6d571bf72be 100644
> --- a/tools/testing/selftests/net/Makefile
> +++ b/tools/testing/selftests/net/Makefile
> @@ -11,6 +11,7 @@ TEST_PROGS := \
>  	amt.sh \
>  	arp_ndisc_evict_nocarrier.sh \
>  	arp_ndisc_untracked_subnets.sh \
> +	arp_no_invalid_sha_poision.sh \
>  	bareudp.sh \
>  	big_tcp.sh \
>  	bind_bhash.sh \

Not sure why but we get:

# selftests: net: arp_no_invalid_sha_poision.sh
# Warning: file arp_no_invalid_sha_poision.sh is missing!
not ok 1 selftests: net: arp_no_invalid_sha_poision.sh

When we run 
	make TARGETS=net run_tests

The word "poison" is misspelled but both in the file name and makefile.
I guess there's another typo somewhere.

Re: [PATCH net-next v4 4/4] selftests/net: add no NDP b/mcast,null poison test

[Jakub Kicinski]

On Sat,  7 Feb 2026 21:40:36 +0100 Marc Suñé wrote:
> @@ -171,6 +172,7 @@ TEST_GEN_PROGS := \
>  	epoll_busy_poll \
>  	icmp_rfc4884 \
>  	ipv6_fragmentation \
> +	ndisc_send \

This needs to go to TEST_GEN_FILES, _PROGS are tests in the kselftest
makefile framework (somewhat confusingly). If we add it here ksft
tries to run it which fails:

# selftests: net: ndisc_send
# 0.01 [+0.01] Usage: ./ndisc_send <iface> <mac_dst> <mac_src> <dst_ip> <src_ip> <target_ip> <op> <lladr>
not ok 1 selftests: net: ndisc_send # exit=255

Re: [PATCH net-next v4 2/4] selftests/net: add no ARP b/mcast,null poison test

[Marc Sune]

Missatge de Jakub Kicinski <kuba@kernel.org> del dia dc., 11 de febr.
2026 a les 3:11:
>
> On Sat,  7 Feb 2026 21:40:34 +0100 Marc Suñé wrote:
> > diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile
> > index afdea6d95bde..c6d571bf72be 100644
> > --- a/tools/testing/selftests/net/Makefile
> > +++ b/tools/testing/selftests/net/Makefile
> > @@ -11,6 +11,7 @@ TEST_PROGS := \
> >       amt.sh \
> >       arp_ndisc_evict_nocarrier.sh \
> >       arp_ndisc_untracked_subnets.sh \
> > +     arp_no_invalid_sha_poision.sh \
> >       bareudp.sh \
> >       big_tcp.sh \
> >       bind_bhash.sh \
>
> Not sure why but we get:
>
> # selftests: net: arp_no_invalid_sha_poision.sh
> # Warning: file arp_no_invalid_sha_poision.sh is missing!
> not ok 1 selftests: net: arp_no_invalid_sha_poision.sh
>
> When we run
>         make TARGETS=net run_tests
>

It seems to work for me (typo already fixed):

sudo make TARGETS=net run_tests

[...]

# timeout set to 3600
# selftests: net: arp_no_invalid_sha_poison.sh
# TEST: 1.1  ARP no poisoning dmac=bcast reply sha=bcast              [ OK ]
# TEST: 1.2  ARP no poisoning dmac=bcast reply sha=null               [ OK ]
# TEST: 1.3  ARP no poisoning dmac=bcast req   sha=bcast              [ OK ]
# TEST: 1.4  ARP no poisoning dmac=bcast req   sha=null               [ OK ]
# TEST: 1.5  ARP no poisoning dmac=bcast req   sha=mcast              [ OK ]
# TEST: 1.6  ARP no poisoning dmac=bcast reply sha=mcast              [ OK ]
# TEST: 1.7  ARP no poisoning dmac=veth0 reply sha=bcast              [ OK ]
# TEST: 1.8  ARP no poisoning dmac=veth0 reply sha=null               [ OK ]
# TEST: 1.9  ARP no poisoning dmac=veth0 req   sha=bcast              [ OK ]
# TEST: 1.10 ARP no poisoning dmac=veth0 req   sha=null               [ OK ]
# TEST: 1.11 ARP no poisoning dmac=veth0 req   sha=mcast              [ OK ]
# TEST: 1.12 ARP no poisoning dmac=veth0 reply sha=mcast              [ OK ]
ok 25 selftests: net: arp_no_invalid_sha_poison.sh

Not sure why you are getting this error, and why selftests didn't fail
in any of the 4 versions in patchwork. I assume tests run there too.

> The word "poison" is misspelled but both in the file name and makefile.
> I guess there's another typo somewhere.

Sigh. Let me fix that, along with your comment on patch 4
(TEST_GEN_FILES vs. _PROGS) on the other thread. I will also fix some
AI review warnings (error traces) on patch 4 that AI reviews _now_
highlighted. It seems AI reviews are non deterministic, as
ndisc_send.c didn't change since v2, and the patch didn't even change
v3->v4.

I guess you'd like me to wait till net-next is open again, correct?

Thank you for the guidance Jakub.

Re: [PATCH net-next v4 2/4] selftests/net: add no ARP b/mcast,null poison test

[Jakub Kicinski]

On Wed, 11 Feb 2026 19:29:01 +0100 Marc Sune wrote:
> > The word "poison" is misspelled but both in the file name and makefile.
> > I guess there's another typo somewhere.  
> 
> Sigh. Let me fix that, along with your comment on patch 4
> (TEST_GEN_FILES vs. _PROGS) on the other thread. I will also fix some
> AI review warnings (error traces) on patch 4 that AI reviews _now_
> highlighted. It seems AI reviews are non deterministic, as
> ndisc_send.c didn't change since v2, and the patch didn't even change
> v3->v4.
> 
> I guess you'd like me to wait till net-next is open again, correct?

Yes, let's wait for net-next.