pf tests: Test that dup-to doesn't produce extra duplicate packets

tests/sys/netpfil/common/pft_ping.py

@@ -34,6 +34,27 @@
 
 PAYLOAD_MAGIC = bytes.fromhex('42c0ffee')
 
+dup_found = 0
+
+def check_dup(args, packet):
+	"""
+	Verify that this is an ICMP packet, and that we only see one
+	"""
+	global dup_found
+
+	icmp = packet.getlayer(sp.ICMP)
+	if not icmp:
+		return False
+
+	raw = packet.getlayer(sp.Raw)
+	if not raw:
+		return False
+	if raw.load != PAYLOAD_MAGIC:
+		return False
+
+	dup_found = dup_found + 1
+	return False
+
 def check_ping_request(args, packet):
 	if args.ip6:
 		return check_ping6_request(args, packet)
@@ -169,6 +190,8 @@ def main():
 		help='The interface through which the packet(s) will be sent')
 	parser.add_argument('--recvif', nargs=1,
 		help='The interface on which to expect the ICMP echo response')
+	parser.add_argument('--checkdup', nargs=1,
+		help='The interface on which to expect the duplicated ICMP packets')
 	parser.add_argument('--ip6', action='store_true',
 		help='Use IPv6')
 	parser.add_argument('--to', nargs=1,
@@ -202,6 +225,10 @@ def main():
 
 		sniffer = Sniffer(args, checkfn)
 
+	dupsniffer = None
+	if args.checkdup is not None:
+		dupsniffer = Sniffer(args, check_dup, recvif=args.checkdup[0])
+
 	if args.tcpsyn:
 		tcpsyn(args.sendif[0], args.to[0], args)
 	else:
@@ -210,6 +237,11 @@ def main():
 		else:
 			ping(args.sendif[0], args.to[0], args)
 
+	if dupsniffer:
+		dupsniffer.join()
+		if dup_found != 1:
+			sys.exit(1)
+
 	if sniffer:
 		sniffer.join()
 

tests/sys/netpfil/common/sniffer.py

@@ -30,11 +30,14 @@
 import scapy.all as sp
 
 class Sniffer(threading.Thread):
-	def __init__(self, args, check_function):
+	def __init__(self, args, check_function, recvif=None):
 		threading.Thread.__init__(self)
 
 		self._args = args
-		self._recvif = args.recvif[0]
+		if recvif is not None:
+			self._recvif = recvif
+		else:
+			self._recvif = args.recvif[0]
 		self._check_function = check_function
 		self.foundCorrectPacket = False
 

tests/sys/netpfil/pf/Makefile

@@ -8,6 +8,7 @@ TESTS_SUBDIRS+=	ioctl
 ATF_TESTS_SH+=	altq \
 		anchor \
 		checksum \
+		dup \
 		forward \
 		fragmentation \
 		icmp \

tests/sys/netpfil/pf/dup.sh

@@ -0,0 +1,81 @@
+# $FreeBSD$
+#
+# SPDX-License-Identifier: BSD-2-Clause-FreeBSD
+#
+# Copyright (c) 2021 Kristof Provost <kp@FreeBSD.org>
+#
+# 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.
+
+. $(atf_get_srcdir)/utils.subr
+
+common_dir=$(atf_get_srcdir)/../common
+
+atf_test_case "dup_to" "cleanup"
+do_to_head()
+{
+	atf_set descr 'dup-to test'
+	atf_set require.user root
+}
+
+dup_to_body()
+{
+	pft_init
+
+	epair_send=$(vnet_mkepair)
+	ifconfig ${epair_send}a 192.0.2.1/24 up
+
+	epair_recv=$(vnet_mkepair)
+	ifconfig ${epair_recv}a up
+
+	epair_dupto=$(vnet_mkepair)
+	ifconfig ${epair_dupto}a up
+
+	vnet_mkjail alcatraz ${epair_send}b ${epair_recv}b ${epair_dupto}b
+	jexec alcatraz ifconfig ${epair_send}b 192.0.2.2/24 up
+	jexec alcatraz ifconfig ${epair_recv}b 198.51.100.2/24 up
+	jexec alcatraz ifconfig ${epair_dupto}b 203.0.113.2/24 up
+	jexec alcatraz sysctl net.inet.ip.forwarding=1
+	jexec alcatraz arp -s 198.51.100.3 00:01:02:03:04:05
+	jexec alcatraz arp -s 203.0.113.3 01:02:03:04:05:06
+	route add -net 198.51.100.0/24 192.0.2.2
+
+	jexec alcatraz pfctl -e
+
+	pft_set_rules alcatraz "pass out on { ${epair_recv}b } \
+	    dup-to (${epair_dupto}b 203.0.113.3)"
+
+	atf_check -s exit:0 ${common_dir}/pft_ping.py \
+		--sendif ${epair_send}a \
+		--to 198.51.100.3 \
+		--recv ${epair_recv}a \
+		--checkdup ${epair_dupto}a
+}
+
+dup_to_cleanup()
+{
+	pft_cleanup
+}
+
+atf_init_test_cases()
+{
+	atf_add_test_case "dup_to"
+}