netpfil tests: Add the set ToS test for ipfw and pf

This test tests the following:

 - The firewall is able to set the tos bits
 - The firewall is able to set the DSCP bits when EN bits is already set and
   the EN bits remains unchanged.
 - The firewall is able to drop the packets based on ToS value

Submitted by:	Ahsan Barkati
Reviewed by:	kp
Sponsored by:	Google, Inc. (GSoC 2019)
Differential Revision:	https://reviews.freebsd.org/D21305

tests/sys/netpfil/common/Makefile

@@ -7,7 +7,8 @@ TESTSDIR=	${TESTSBASE}/sys/netpfil/common
 
 ATF_TESTS_SH+=	\
 		pass_block \
-		nat
+		nat \
+		tos
 
 ${PACKAGE}FILES+=	\
 		utils.subr \

tests/sys/netpfil/common/tos.sh

@@ -0,0 +1,118 @@
+#-
+# SPDX-License-Identifier: BSD-2-Clause-FreeBSD
+#
+# Copyright (c) 2019 Ahsan Barkati
+#
+# 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.
+#
+# $FreeBSD$
+#
+
+. $(atf_get_srcdir)/utils.subr
+. $(atf_get_srcdir)/runner.subr
+
+tos_head()
+{
+	atf_set descr 'set-tos test'
+	atf_set require.user root
+	atf_set require.progs scapy
+}
+
+tos_body()
+{
+	firewall=$1
+	firewall_init $firewall
+
+	epair_send=$(vnet_mkepair)
+	ifconfig ${epair_send}a 192.0.2.1/24 up
+
+	epair_recv=$(vnet_mkepair)
+	ifconfig ${epair_recv}a up
+
+	vnet_mkjail iron ${epair_send}b ${epair_recv}b
+	jexec iron ifconfig ${epair_send}b 192.0.2.2/24 up
+	jexec iron ifconfig ${epair_recv}b 198.51.100.2/24 up
+	jexec iron sysctl net.inet.ip.forwarding=1
+	jexec iron arp -s 198.51.100.3 00:01:02:03:04:05
+	route add -net 198.51.100.0/24 192.0.2.2
+
+	# Check if the firewall is able to set the ToS bits
+	firewall_config "iron" ${firewall} \
+		"pf" \
+			"scrub out proto icmp set-tos 36" \
+		"ipfw" \
+			"ipfw -q add 100 setdscp 9 ip from any to any"
+		# dscp is set to 9 because last two bits are for
+		# EN and hence tos would be 36
+
+	atf_check -s exit:0 $(atf_get_srcdir)/pft_ping.py \
+		--sendif ${epair_send}a \
+		--to 198.51.100.3 \
+		--recvif ${epair_recv}a \
+		--expect-tos 36
+
+	# Check if the firewall is able to set the ToS bits
+	# and persists the EN bits (if already set)
+	firewall_config "iron" ${firewall} \
+		"pf" \
+			"scrub out proto icmp set-tos 36" \
+		"ipfw" \
+			"ipfw -q add 100 setdscp 9 ip from any to any"
+
+	atf_check -s exit:0 $(atf_get_srcdir)/pft_ping.py \
+		--sendif ${epair_send}a \
+		--to 198.51.100.3 \
+		--recvif ${epair_recv}a \
+		--send-tos 3 \
+		--expect-tos 39
+
+	# Check if the firewall is able to filter the
+	# packets based on the ToS value
+	firewall_config "iron" ${firewall} \
+		"pf" \
+			"block all tos 36" \
+		"ipfw" \
+			"ipfw -q add 100 deny all from any to any dscp 9"
+
+	atf_check -s exit:1 $(atf_get_srcdir)/pft_ping.py \
+		--sendif ${epair_send}a \
+		--to 198.51.100.3 \
+		--recvif ${epair_recv}a \
+		--send-tos 36
+
+	atf_check -s exit:0 $(atf_get_srcdir)/pft_ping.py \
+		--sendif ${epair_send}a \
+		--to 198.51.100.3 \
+		--recvif ${epair_recv}a \
+		--send-tos 32
+}
+
+tos_cleanup()
+{
+	firewall=$1
+	firewall_cleanup $firewall
+}
+
+setup_tests \
+		"tos" \
+			"pf" \
+			"ipfw"