netpfil tests: Add functions for testing routing scenarios

Many pf tests use identical setup where one jail is a router and
optionally another jail is a server. Add functions to create such jails
for IPv6 and IPv4 and functions to perform tests on such setup.

Add tests using those functions: scrub actions, routing table, tcp
sequence number modulation.

Reviewed by:	kp
Sponsored by:	InnoGames GmbH
Differential Revision:	https://reviews.freebsd.org/D38126

tests/sys/netpfil/pf/Makefile

@@ -7,7 +7,6 @@ TESTS_SUBDIRS+=	ioctl
 
 ATF_TESTS_SH+=	altq \
 		anchor \
-		checksum \
 		dup \
 		ether \
 		forward \
@@ -18,6 +17,7 @@ ATF_TESTS_SH+=	altq \
 		macro \
 		map_e \
 		match \
+		modulate \
 		names \
 		nat \
 		pass_block \
@@ -27,7 +27,9 @@ ATF_TESTS_SH+=	altq \
 		rdr \
 		ridentifier \
 		route_to \
+		rtable \
 		rules_counter \
+		scrub \
 		set_skip \
 		set_tos \
 		src_track \

tests/sys/netpfil/pf/fragmentation.sh

@@ -327,6 +327,43 @@ reassemble_cleanup()
 	pft_cleanup
 }
 
+atf_test_case "no_df" "cleanup"
+no_df_head()
+{
+	atf_set descr 'Test removing of DF flag'
+	atf_set require.user root
+}
+
+no_df_body()
+{
+	setup_router_server_ipv4
+
+	# Tester can send long packets which will get fragmented by the router.
+	# Replies from server will come in fragments which might get
+	# reassembled resulting in a long reply packet sent back to tester.
+	ifconfig ${epair_tester}a mtu 9000
+	jexec router ifconfig ${epair_tester}b mtu 9000
+	jexec router ifconfig ${epair_server}a mtu 1500
+	jexec server ifconfig ${epair_server}b mtu 1500
+
+	# Sanity check.
+	ping_server_check_reply exit:0 --ping-type=icmp
+
+	# Enable packet reassembly with clearing of the no-df flag.
+	pft_set_rules router \
+		"scrub all fragment reassemble no-df" \
+		"block" \
+		"pass inet proto icmp all icmp-type echoreq"
+	# Ping with non-fragmentable packets.
+	# pf will strip the DF flag resulting in fragmentation and packets
+	# getting properly forwarded.
+	ping_server_check_reply exit:0 --ping-type=icmp --send-length=2000 --send-flags DF
+}
+no_df_cleanup()
+{
+	pft_cleanup
+}
+
 atf_init_test_cases()
 {
 	atf_add_test_case "too_many_fragments"
@@ -336,4 +373,5 @@ atf_init_test_cases()
 	atf_add_test_case "overindex"
 	atf_add_test_case "overlimit"
 	atf_add_test_case "reassemble"
+	atf_add_test_case "no_df"
 }

tests/sys/netpfil/pf/modulate.sh

@@ -1,6 +1,8 @@
+# $FreeBSD$
+#
 # SPDX-License-Identifier: BSD-2-Clause-FreeBSD
 #
-# Copyright (c) 2020 Kristof Provost <kp@FreeBSD.org>
+# Copyright (c) 2023 Kajetan Staszkiewicz <vegetga@tuxpowered.net>
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions
@@ -25,62 +27,54 @@
 
 . $(atf_get_srcdir)/utils.subr
 
-common_dir=$(atf_get_srcdir)/../common
+atf_test_case "modulate_v4" "cleanup"
-
+modulate_v4_head()
-atf_test_case "unaligned" "cleanup"
-unaligned_head()
 {
-	atf_set descr 'Test unaligned checksum updates'
+	atf_set descr 'IPv4 TCP sequence number modulation'
 	atf_set require.user root
 	atf_set require.progs scapy
 }
 
-unaligned_body()
+modulate_v4_body()
 {
-	pft_init
+	setup_router_dummy_ipv4
 
-	epair_in=$(vnet_mkepair)
+	pft_set_rules router \
-	epair_out=$(vnet_mkepair)
+		"pass in on ${epair_tester}b modulate state"
-
+	ping_dummy_check_request exit:0 --ping-type=tcpsyn --send-seq 42 # Sanity check
-	vnet_mkjail alcatraz ${epair_in}b ${epair_out}a
+	ping_dummy_check_request exit:1 --ping-type=tcpsyn --send-seq 42 --expect-seq 42
-
-	ifconfig ${epair_in}a 192.0.2.2/24 up
-	route add -net 198.51.100.0/24 192.0.2.1
-
-	jexec alcatraz ifconfig ${epair_in}b 192.0.2.1/24 up
-	jexec alcatraz sysctl net.inet.ip.forwarding=1
-
-	jexec alcatraz ifconfig ${epair_out}a 198.51.100.1/24 up
-	jexec alcatraz arp -s 198.51.100.2 00:01:02:03:04:05
-
-	ifconfig ${epair_out}b up
-
-	jexec alcatraz pfctl -e
-	pft_set_rules alcatraz \
-		"scrub on ${epair_in}b reassemble tcp max-mss 1200"
-
-	# Check aligned
-	atf_check -s exit:0 ${common_dir}/pft_ping.py \
-		--sendif ${epair_in}a \
-		--to 198.51.100.2 \
-		--recvif ${epair_out}b \
-		--ping-type tcpsyn
-
-	# And unaligned
-	atf_check -s exit:0 ${common_dir}/pft_ping.py \
-		--sendif ${epair_in}a \
-		--to 198.51.100.2 \
-		--recvif ${epair_out}b \
-		--ping-type tcpsyn \
-		--send-tcpopt-unaligned
 }
 
-unaligned_cleanup()
+modulate_v4_cleanup()
+{
+	pft_cleanup
+}
+
+atf_test_case "modulate_v6" "cleanup"
+modulate_v6_head()
+{
+	atf_set descr 'IPv6 TCP sequence number modulation'
+	atf_set require.user root
+	atf_set require.progs scapy
+}
+
+modulate_v6_body()
+{
+	setup_router_dummy_ipv6
+
+	pft_set_rules router \
+		"pass in on ${epair_tester}b modulate state"
+	ping_dummy_check_request exit:0 --ping-type=tcpsyn --send-seq 42 # Sanity check
+	ping_dummy_check_request exit:1 --ping-type=tcpsyn --send-seq 42 --expect-seq 42
+}
+
+modulate_v6_cleanup()
 {
 	pft_cleanup
 }
 
 atf_init_test_cases()
 {
-	atf_add_test_case "unaligned"
+	atf_add_test_case "modulate_v4"
+	atf_add_test_case "modulate_v6"
 }

tests/sys/netpfil/pf/rtable.sh

@@ -0,0 +1,131 @@
+# $FreeBSD$
+#
+# SPDX-License-Identifier: BSD-2-Clause-FreeBSD
+#
+# Copyright (c) 2023 Kajetan Staszkiewicz <vegetga@tuxpowered.net>
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+# SUCH DAMAGE.
+
+. $(atf_get_srcdir)/utils.subr
+
+atf_test_case "forward_v4" "cleanup"
+forward_v4_head()
+{
+	atf_set descr 'Test IPv4 forwarding with rtable'
+	atf_set require.user root
+	atf_set require.progs scapy
+}
+
+forward_v4_body()
+{
+	setup_router_server_ipv4
+
+	# Sanity check
+	ping_server_check_reply exit:0
+
+	jexec router sysctl net.fibs=2
+	jexec router ifconfig ${epair_server}a fib 1
+	jexec router route del -net ${net_server}
+	jexec router route add -fib 1 -net ${net_server} -iface ${epair_server}a
+
+	# Sanity check
+	ping_server_check_reply exit:1
+
+	# This rule is not enough.
+	# Echo requests will be properly forwarded but replies can't be routed back.
+	pft_set_rules router \
+		"pass in on ${epair_tester}b inet proto icmp all icmp-type echoreq rtable 1"
+	ping_server_check_reply exit:1
+
+	# Allow replies coming back to the tester properly via stateful filtering post-routing.
+	pft_set_rules router \
+		"pass in  on ${epair_tester}b inet proto icmp all icmp-type echoreq rtable 1" \
+		"pass out on ${epair_server}a inet proto icmp all icmp-type echoreq rtable 0"
+	ping_server_check_reply exit:0
+
+	# Allow replies coming back to the tester properly via provding extra routes in rtable 1
+	pft_set_rules router \
+		"pass in  on ${epair_tester}b inet proto icmp all icmp-type echoreq rtable 1"
+	jexec router route add -fib 1 -net ${net_tester} -iface ${epair_tester}b
+	ping_server_check_reply exit:0
+}
+
+forward_v4_cleanup()
+{
+	pft_cleanup
+}
+
+atf_test_case "forward_v6" "cleanup"
+forward_v6_head()
+{
+	atf_set descr 'Test IPv6 forwarding with rtable'
+	atf_set require.user root
+	atf_set require.progs scapy
+}
+
+forward_v6_body()
+{
+	setup_router_server_ipv6
+
+	# Sanity check
+	ping_server_check_reply exit:0
+
+	jexec router sysctl net.fibs=2
+	jexec router ifconfig ${epair_server}a fib 1
+	jexec router route del -6 ${net_server}
+	jexec router route add -fib 1 -6 ${net_server} -iface ${epair_server}a
+
+	# Sanity check
+	ping_server_check_reply exit:1
+
+	# This rule is not enough.
+	# Echo requests will be properly forwarded but replies can't be routed back.
+	pft_set_rules router \
+		"pass inet6 proto icmp6 icmp6-type { neighbrsol, neighbradv }" \
+		"pass in on ${epair_tester}b inet6 proto icmp6 icmp6-type echoreq"
+	ping_server_check_reply exit:1
+
+	# Allow replies coming back to the tester properly via stateful filtering post-routing.
+	pft_set_rules router \
+		"pass inet6 proto icmp6 icmp6-type { neighbrsol, neighbradv }" \
+		"pass in  on ${epair_tester}b inet6 proto icmp6 icmp6-type echoreq rtable 1" \
+		"pass out on ${epair_server}a inet6 proto icmp6 icmp6-type echoreq rtable 0"
+	ping_server_check_reply exit:0
+
+	# Allow replies coming back to the tester properly via provding extra routes in rtable 1
+	pft_set_rules router \
+		"pass inet6 proto icmp6 icmp6-type { neighbrsol, neighbradv }" \
+		"pass in  on ${epair_tester}b inet6 proto icmp6 icmp6-type echoreq rtable 1"
+	jexec router route add -fib 1 -6 ${net_tester} -iface ${epair_tester}b
+	ping_server_check_reply exit:0
+}
+
+forward_v6_cleanup()
+{
+	pft_cleanup
+}
+
+atf_init_test_cases()
+{
+	atf_add_test_case "forward_v4"
+	atf_add_test_case "forward_v6"
+}

tests/sys/netpfil/pf/scrub.sh

@@ -0,0 +1,221 @@
+# $FreeBSD$
+#
+# SPDX-License-Identifier: BSD-2-Clause-FreeBSD
+#
+# Copyright (c) 2020 Kristof Provost <kp@FreeBSD.org>
+# Copyright (c) 2023 Kajetan Staszkiewicz <vegeta@tuxpowered.net>
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+# SUCH DAMAGE.
+
+. $(atf_get_srcdir)/utils.subr
+
+atf_test_case "max_mss_v4" "cleanup"
+max_mss_v4_head()
+{
+	atf_set descr 'Test IPv4 scrub "mss" rule'
+	atf_set require.user root
+	atf_set require.progs scapy
+}
+
+max_mss_v4_body()
+{
+	setup_router_dummy_ipv4
+	pft_set_rules router "scrub on ${epair_tester}b max-mss 1300"
+	# Check aligned
+	ping_dummy_check_request exit:0 --ping-type=tcpsyn --send-mss=1400 --expect-mss=1300
+	# And unaligned
+	ping_dummy_check_request exit:0 --ping-type=tcpsyn --send-mss=1400 --expect-mss=1300 \
+	    --send-tcpopt-unaligned
+}
+
+max_mss_v4_cleanup()
+{
+	pft_cleanup
+}
+
+
+atf_test_case "max_mss_v6" "cleanup"
+max_mss_v6_head()
+{
+	atf_set descr 'Test IPv6 scrub "mss" rule'
+	atf_set require.user root
+	atf_set require.progs scapy
+}
+
+max_mss_v6_body()
+{
+	setup_router_dummy_ipv6
+	pft_set_rules router "scrub on ${epair_tester}b max-mss 1300"
+	# Check aligned
+	ping_dummy_check_request exit:0 --ping-type=tcpsyn --send-mss=1400 --expect-mss=1300
+	# And unaligned
+	ping_dummy_check_request exit:0 --ping-type=tcpsyn --send-mss=1400 --expect-mss=1300 \
+	    --send-tcpopt-unaligned
+}
+
+max_mss_v6_cleanup()
+{
+	pft_cleanup
+}
+
+
+atf_test_case "set_tos_v4" "cleanup"
+set_tos_v4_head()
+{
+	atf_set descr 'Test IPv4 scub "set-tos" rule'
+	atf_set require.user root
+	atf_set require.progs scapy
+}
+
+set_tos_v4_body()
+{
+	setup_router_dummy_ipv4
+	pft_set_rules router "scrub on ${epair_tester}b set-tos 0x42"
+	ping_dummy_check_request exit:0 --send-tc=0 --expect-tc=66
+}
+
+set_tos_v4_cleanup()
+{
+	pft_cleanup
+}
+
+
+atf_test_case "set_tos_v6" "cleanup"
+set_tos_v6_head()
+{
+	atf_set descr 'Test IPv6 scub "set-tos" rule'
+	atf_set require.user root
+	atf_set require.progs scapy
+}
+
+set_tos_v6_body()
+{
+	setup_router_dummy_ipv6
+	pft_set_rules router "scrub on ${epair_tester}b set-tos 0x42"
+	ping_dummy_check_request exit:0 --ping-type=tcpsyn --send-tc=0 --expect-tc=66
+}
+
+set_tos_v6_cleanup()
+{
+	pft_cleanup
+}
+
+
+atf_test_case "min_ttl_v4" "cleanup"
+min_ttl_v4_head()
+{
+	atf_set descr 'Test IPv4 scub "min-ttl" rule'
+	atf_set require.user root
+	atf_set require.progs scapy
+}
+
+min_ttl_v4_body()
+{
+	setup_router_dummy_ipv4
+	pft_set_rules router "scrub on ${epair_tester}b min-ttl 50"
+	ping_dummy_check_request exit:0 --ping-type=tcpsyn --send-hlim=40 --expect-hlim=49
+}
+
+min_ttl_v4_cleanup()
+{
+	pft_cleanup
+}
+
+
+atf_test_case "min_ttl_v6" "cleanup"
+min_ttl_v6_head()
+{
+	atf_set descr 'Test IPv6 scub "min-ttl" rule'
+	atf_set require.user root
+	atf_set require.progs scapy
+}
+
+min_ttl_v6_body()
+{
+	setup_router_dummy_ipv6
+	pft_set_rules router "scrub on ${epair_tester}b min-ttl 50"
+	ping_dummy_check_request exit:0 --ping-type=tcpsyn --send-hlim=40 --expect-hlim=49
+}
+
+min_ttl_v6_cleanup()
+{
+	pft_cleanup
+}
+
+
+atf_test_case "no_scrub_v4" "cleanup"
+no_scrub_v4_head()
+{
+	atf_set descr 'Test IPv4 "no scrub" rule'
+	atf_set require.user root
+	atf_set require.progs scapy
+}
+
+no_scrub_v4_body()
+{
+	setup_router_dummy_ipv4
+	pft_set_rules router\
+		"no scrub on ${epair_tester}b to ${net_server_host_server}"
+		"scrub on ${epair_tester}b set-tos 0x42"
+	ping_dummy_check_request exit:0 --send-tc=0 --expect-tc=0
+}
+
+no_scrub_v4_cleanup()
+{
+	pft_cleanup
+}
+
+
+atf_test_case "no_scrub_v6" "cleanup"
+no_scrub_v6_head()
+{
+	atf_set descr 'Test IPv6 "no scrub" rule'
+	atf_set require.user root
+	atf_set require.progs scapy
+}
+
+no_scrub_v6_body()
+{
+	setup_router_dummy_ipv6
+	pft_set_rules router \
+		"no scrub on ${epair_tester}b to ${net_server_host_server}"
+		"scrub on ${epair_tester}b set-tos 0x42"
+	ping_dummy_check_request exit:0 --send-tc=0 --expect-tc=0
+}
+
+no_scrub_v6_cleanup()
+{
+	pft_cleanup
+}
+
+
+atf_init_test_cases()
+{
+	atf_add_test_case "max_mss_v4"
+	atf_add_test_case "max_mss_v6"
+	atf_add_test_case "set_tos_v4"
+	atf_add_test_case "set_tos_v6"
+	atf_add_test_case "min_ttl_v4"
+	atf_add_test_case "min_ttl_v6"
+	atf_add_test_case "no_scrub_v4"
+	atf_add_test_case "no_scrub_v6"
+}

tests/sys/netpfil/pf/utils.subr

@@ -4,6 +4,7 @@
 # SPDX-License-Identifier: BSD-2-Clause-FreeBSD
 #
 # Copyright (c) 2017 Kristof Provost <kp@FreeBSD.org>
+# Copyright (c) 2023 Kajetan Staszkiewicz <vegeta@tuxpowered.net>
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions
@@ -27,6 +28,7 @@
 # SUCH DAMAGE.
 
 . $(atf_get_srcdir)/../../common/vnet.subr
+common_dir=$(atf_get_srcdir)/../common
 
 pft_onerror()
 {
@@ -153,3 +155,137 @@ altq_cleanup()
 {
 	pft_cleanup
 }
+
+# Create a bare router jail.
+# This function lacks target configuration.
+setup_router_ipv4()
+{
+	pft_init
+
+	epair_tester=$(vnet_mkepair)
+	epair_server=$(vnet_mkepair)
+
+	net_tester=192.0.2.0/24
+	net_tester_mask=24
+	net_tester_host_router=192.0.2.1
+	net_tester_host_tester=192.0.2.2
+
+	net_server=198.51.100.0/24
+	net_server_mask=24
+	net_server_host_router=198.51.100.1
+	net_server_host_server=198.51.100.2
+
+	vnet_mkjail router ${epair_tester}b ${epair_server}a
+
+	ifconfig ${epair_tester}a ${net_tester_host_tester}/${net_tester_mask} up
+	route add -net ${net_server} ${net_tester_host_router}
+
+	jexec router ifconfig ${epair_tester}b ${net_tester_host_router}/${net_tester_mask} up
+	jexec router sysctl net.inet.ip.forwarding=1
+	jexec router ifconfig ${epair_server}a ${net_server_host_router}/${net_server_mask} up
+
+	jexec router pfctl -e
+}
+
+# Create a router jail.
+# The target for tests does not exist but a static ARP entry does
+# so packets to it can be properly routed.
+setup_router_dummy_ipv4()
+{
+	setup_router_ipv4
+	jexec router arp -s ${net_server_host_server} 00:01:02:03:04:05
+	ifconfig ${epair_server}b up
+}
+
+# Create a router and a server jail.
+# The server is capable of responding to pings from the tester.
+setup_router_server_ipv4()
+{
+	setup_router_ipv4
+	vnet_mkjail server ${epair_server}b
+	jexec server ifconfig ${epair_server}b ${net_server_host_server}/${net_server_mask} up
+	jexec server route add -net ${net_tester} ${net_server_host_router}
+	jexec server nc -4l 666 &
+	sleep 1 # Give nc time to start and listen
+}
+
+# Create a bare router jail.
+# This function lacks target configuration.
+setup_router_ipv6()
+{
+	pft_init
+
+	epair_tester=$(vnet_mkepair)
+	epair_server=$(vnet_mkepair)
+
+	net_tester=2001:db8:42::/64
+	net_tester_mask=64
+	net_tester_host_router=2001:db8:42::1
+	net_tester_host_tester=2001:db8:42::2
+
+	net_server=2001:db8:43::/64
+	net_server_mask=64
+	net_server_host_router=2001:db8:43::1
+	net_server_host_server=2001:db8:43::2
+
+	vnet_mkjail router ${epair_tester}b ${epair_server}a
+
+	ifconfig ${epair_tester}a inet6 ${net_tester_host_tester}/${net_tester_mask}up no_dad
+	route add -6 ${net_server} ${net_tester_host_router}
+
+	jexec router ifconfig ${epair_tester}b inet6 ${net_tester_host_router}/${net_tester_mask} up no_dad
+	jexec router sysctl net.inet6.ip6.forwarding=1
+	jexec router ifconfig ${epair_server}a inet6 ${net_server_host_router}/${net_server_mask} up no_dad
+
+	jexec router pfctl -e
+}
+
+# Create a router jail.
+# The target for tests does not exist but a static NDP entry does
+# so packets to it can be properly routed.
+setup_router_dummy_ipv6()
+{
+	setup_router_ipv6
+	jexec router ndp -s ${net_server_host_server} 00:01:02:03:04:05
+	ifconfig ${epair_server}b up
+}
+
+# Create a router and a server jail.
+# The server is capable of responding to pings from tester.
+setup_router_server_ipv6()
+{
+	setup_router_ipv6
+	vnet_mkjail server ${epair_server}b
+	jexec server ifconfig ${epair_server}b inet6 ${net_server_host_server}/${net_server_mask} up no_dad
+	jexec server route add -6 ${net_tester} ${net_server_host_router}
+	jexec server nc -6l 666 &
+	sleep 1 # Give nc time to start and listen
+}
+
+# Ping the dummy static NDP target.
+# Check for pings being forwarded through the router towards the target.
+ping_dummy_check_request()
+{
+	exit_condition=$1
+	shift
+	params=$@
+	atf_check -s ${exit_condition} ${common_dir}/pft_ping.py \
+	    --sendif ${epair_tester}a \
+	    --to ${net_server_host_server} \
+	    --recvif ${epair_server}b \
+	$params
+}
+
+# Ping the server jail.
+# Check for responses coming back throught the router back to the tester.
+ping_server_check_reply()
+{
+	exit_condition=$1
+	shift
+	params=$@
+	atf_check -s ${exit_condition} ${common_dir}/pft_ping.py \
+	    --sendif ${epair_tester}a \
+	    --to ${net_server_host_server} \
+	    --replyif ${epair_tester}a \
+	$params
+}