pf tests: ensure that pflog shows malformed packets as blocked, not passed

Sponsored by:	Rubicon Communications, LLC ("Netgate")

tests/sys/netpfil/common/pft_ping.py

@@ -68,7 +68,11 @@ def prepare_ipv4(dst_address, send_params):
     flags = send_params.get('flags')
     tos = send_params.get('tc')
     ttl = send_params.get('hlim')
-    ip = sp.IP(dst=dst_address)
+    opt = send_params.get('nop')
+    options = ''
+    if opt:
+        options='\x00'
+    ip = sp.IP(dst=dst_address, options=options)
     if src_address:
         ip.src = src_address
     if flags:
@@ -443,6 +447,8 @@ def parse_args():
         help='IPv6 Traffic Class or IPv4 DiffServ / ToS')
     parser_send.add_argument('--send-tcpopt-unaligned', action='store_true',
          help='Include unaligned TCP options')
+    parser_send.add_argument('--send-nop', action='store_true',
+         help='Include a NOP IPv4 option')
 
     # Expectations
     parser_expect = parser.add_argument_group('Values expected in sniffed packets')
@@ -489,6 +495,7 @@ def main():
 
     expect_params['length'] = send_params['length']
     send_params['tcpopt_unaligned'] = args.send_tcpopt_unaligned
+    send_params['nop'] = args.send_nop
     send_params['src_address'] = args.fromaddr[0] if args.fromaddr else None
 
     # We may not have a default route. Tell scapy where to start looking for routes

tests/sys/netpfil/pf/Makefile

@@ -24,6 +24,7 @@ ATF_TESTS_SH+=	altq \
 		names \
 		nat \
 		pass_block \
+		pflog \
 		pfsync	\
 		prio \
 		proxy \

tests/sys/netpfil/pf/pflog.sh

@@ -0,0 +1,85 @@
+#
+# SPDX-License-Identifier: BSD-2-Clause
+#
+# Copyright (c) 2023 Rubicon Communications, LLC (Netgate)
+#
+# 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 "malformed" "cleanup"
+malformed_head()
+{
+	atf_set descr 'Test that we do not log malformed packets as passing'
+	atf_set require.user root
+	atf_set require.progs scapy
+}
+
+malformed_body()
+{
+	pflog_init
+
+	epair=$(vnet_mkepair)
+
+	vnet_mkjail srv ${epair}b
+	jexec srv ifconfig ${epair}b 192.0.2.1/24 up
+
+	vnet_mkjail cl ${epair}a
+	jexec cl ifconfig ${epair}a 192.0.2.2/24 up
+
+	jexec cl pfctl -e
+	jexec cl ifconfig pflog0 up
+	pft_set_rules cl \
+		"pass log keep state"
+
+	# Not required, but the 'pf: dropping packet with ip options' kernel log can
+	# help when debugging the test.
+	jexec cl pfctl -x loud
+
+	jexec cl tcpdump -n -e -ttt --immediate-mode -l -U -i pflog0 >> pflog.txt &
+	sleep 1 # Wait for tcpdump to start
+
+	# Sanity check
+	atf_check -s exit:0 -o ignore \
+	    jexec srv ping -c 1 192.0.2.2
+
+	jexec srv ${common_dir}/pft_ping.py  \
+	    --sendif ${epair}b \
+	    --to 192.0.2.2 \
+	    --send-nop \
+	    --recvif ${epair}b
+
+	atf_check -o match:".*rule 0/8\(ip-option\): block in on ${epair}a: 192.0.2.1 > 192.0.2.2: ICMP echo request.*" \
+	    cat pflog.txt
+}
+
+malformed_cleanup()
+{
+	pft_cleanup
+}
+
+atf_init_test_cases()
+{
+	atf_add_test_case "malformed"
+}