wg(4): Add a test that the driver handles a decryption failure

The test uses a fail point to inject a decryption error in OCF while
sending a ping across the tunnel.  The driver should then fail to
respond to the ping and increment the input error counter on the
interface.

Approved by:	so
Security:	FreeBSD-SA-26:52.if_wg
Security:	CVE-2026-58085
Reviewed by:	markj
Sponsored by:	Chelsio Communications

etc/mtree/BSD.tests.dist

@@ -848,6 +848,8 @@
             ..
             routing
             ..
+            wg
+            ..
         ..
         netgraph
         ..

tests/sys/net/Makefile

@@ -15,6 +15,7 @@ ATF_TESTS_SH+=	if_vlan
 ATF_TESTS_SH+=	if_wg
 
 TESTS_SUBDIRS+=	if_ovpn
+TESTS_SUBDIRS+=	wg
 TESTS_SUBDIRS+=	routing
 
 # The netmap bridge application is used by if_wg tests.

tests/sys/net/wg/Makefile

@@ -0,0 +1,10 @@
+PACKAGE=	tests
+
+TESTSDIR=	${TESTSBASE}/sys/net/wg
+BINDIR=		${TESTSDIR}
+
+ATF_TESTS_SH+=	if_wg_nojail
+
+TEST_METADATA.if_wg_nojail=	is_exclusive=true
+
+.include <bsd.test.mk>

tests/sys/net/wg/if_wg_nojail.sh

@@ -0,0 +1,111 @@
+#
+# SPDX-License-Identifier: BSD-2-Clause
+#
+# Copyright (c) 2021 The FreeBSD Foundation
+#
+# This software was developed by Mark Johnston under sponsorship
+# from the FreeBSD Foundation.
+#
+# 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.
+
+. $(atf_get_srcdir)/../../common/vnet.subr
+
+atf_test_case "wg_bad_decrypt" "cleanup"
+wg_bad_decrypt_head()
+{
+	atf_set descr 'Create a wg(4) tunnel over an epair and inject a decryption error'
+	atf_set require.user root
+	atf_set require.kmods if_wg
+}
+
+wg_bad_decrypt_body()
+{
+	local epair pri1 pri2 pub1 pub2 wg1 wg2
+        local endpoint1 endpoint2 tunnel1 tunnel2
+
+	pri1=$(wg genkey)
+	pri2=$(wg genkey)
+
+	endpoint1=192.168.2.1
+	endpoint2=192.168.2.2
+	tunnel1=169.254.0.1
+	tunnel2=169.254.0.2
+
+	epair=$(vnet_mkepair)
+
+	vnet_init
+
+	vnet_mkjail wgtest1 ${epair}a
+	vnet_mkjail wgtest2 ${epair}b
+
+	jexec wgtest1 ifconfig ${epair}a ${endpoint1}/24 up
+	jexec wgtest2 ifconfig ${epair}b ${endpoint2}/24 up
+
+	wg1=$(jexec wgtest1 ifconfig wg create)
+	echo "$pri1" | jexec wgtest1 wg set $wg1 listen-port 12345 \
+	    private-key /dev/stdin
+	pub1=$(jexec wgtest1 wg show $wg1 public-key)
+	wg2=$(jexec wgtest2 ifconfig wg create)
+	echo "$pri2" | jexec wgtest2 wg set $wg2 listen-port 12345 \
+	    private-key /dev/stdin
+	pub2=$(jexec wgtest2 wg show $wg2 public-key)
+
+	atf_check -s exit:0 -o ignore \
+	    jexec wgtest1 wg set $wg1 peer "$pub2" \
+	    endpoint ${endpoint2}:12345 allowed-ips ${tunnel2}/32
+	atf_check -s exit:0 \
+	    jexec wgtest1 ifconfig $wg1 inet ${tunnel1}/24 up
+
+	atf_check -s exit:0 -o ignore \
+	    jexec wgtest2 wg set $wg2 peer "$pub1" \
+	    endpoint ${endpoint1}:12345 allowed-ips ${tunnel1}/32
+	atf_check -s exit:0 \
+	    jexec wgtest2 ifconfig $wg2 inet ${tunnel2}/24 up
+
+	# Generous timeout since the handshake takes some time.
+	atf_check -s exit:0 -o ignore jexec wgtest1 ping -c 1 -t 5 $tunnel2
+
+	# No receive errors before injection
+	ierrs=$(netstat -j wgtest2 -I $wg2 --libxo json,pretty | \
+			awk '/received-errors/ { print $2 }')
+	atf_check_equal "0," "$ierrs"
+
+	# Trigger a decryption error
+	atf_check -s exit:0 -o ignore \
+	    sysctl debug.fail_point.crypto.inject_badmsg="1*return"
+
+	atf_check -s exit:2 -o ignore jexec wgtest1 ping -c 1 -t 5 $tunnel2
+
+	ierrs=$(netstat -j wgtest2 -I $wg2 --libxo json,pretty | \
+			awk '/received-errors/ { print $2 }')
+	atf_check_equal "1," "$ierrs"
+}
+
+wg_bad_decrypt_cleanup()
+{
+	vnet_cleanup
+}
+
+atf_init_test_cases()
+{
+	atf_add_test_case "wg_bad_decrypt"
+}