Page MenuHomeFreeBSD
Files F154300305

D42355.id129408.diff
No OneTemporary
Actions

D42355.id129408.diff
View Options

diff --git a/sys/netpfil/pf/pf_norm.c b/sys/netpfil/pf/pf_norm.c
--- a/sys/netpfil/pf/pf_norm.c
+++ b/sys/netpfil/pf/pf_norm.c
@@ -1043,14 +1043,22 @@
int ip_len;
int tag = -1;
int verdict;
- int srs;
+ bool scrub_compat;
PF_RULES_RASSERT();
r = TAILQ_FIRST(pf_main_ruleset.rules[PF_RULESET_SCRUB].active.ptr);
- /* Check if there any scrub rules. Lack of scrub rules means enforced
- * packet normalization operation just like in OpenBSD. */
- srs = (r != NULL);
+ /*
+ * Check if there are any scrub rules, matching or not.
+ * Lack of scrub rules means:
+ * - enforced packet normalization operation just like in OpenBSD
+ * - fragment reassembly depends on V_pf_status.reass
+ * With scrub rules:
+ * - packet normalization is performed if there is a matching scrub rule
+ * - fragment reassembly is performed if the matching rule has no
+ * PFRULE_FRAGMENT_NOREASS flag
+ */
+ scrub_compat = (r != NULL);
while (r != NULL) {
pf_counter_u64_add(&r->evaluations, 1);
if (pfi_kkif_match(r->kif, kif) == r->ifnot)
@@ -1076,7 +1084,7 @@
break;
}
- if (srs) {
+ if (scrub_compat) {
/* With scrub rules present IPv4 normalization happens only
* if one of rules has matched and it's not a "no scrub" rule */
if (r == NULL || r->action == PF_NOSCRUB)
@@ -1087,12 +1095,6 @@
pf_counter_u64_add_protected(&r->bytes[pd->dir == PF_OUT], pd->tot_len);
pf_counter_u64_critical_exit();
pf_rule_to_actions(r, &pd->act);
- } else if ((!V_pf_status.reass && (h->ip_off & htons(IP_MF | IP_OFFMASK)))) {
- /* With no scrub rules IPv4 fragment reassembly depends on the
- * global switch. Fragments can be dropped early if reassembly
- * is disabled. */
- REASON_SET(reason, PFRES_NORM);
- goto drop;
}
/* Check for illegal packets */
@@ -1107,9 +1109,10 @@
}
/* Clear IP_DF if the rule uses the no-df option or we're in no-df mode */
- if ((((r && r->rule_flag & PFRULE_NODF) ||
- (V_pf_status.reass & PF_REASS_NODF)) && h->ip_off & htons(IP_DF)
- )) {
+ if (((!scrub_compat && V_pf_status.reass & PF_REASS_NODF) ||
+ (r != NULL && r->rule_flag & PFRULE_NODF)) &&
+ (h->ip_off & htons(IP_DF))
+ ) {
u_int16_t ip_off = h->ip_off;
h->ip_off &= htons(~IP_DF);
@@ -1143,7 +1146,9 @@
goto bad;
}
- if (r==NULL || !(r->rule_flag & PFRULE_FRAGMENT_NOREASS)) {
+ if ((!scrub_compat && V_pf_status.reass) ||
+ (r != NULL && !(r->rule_flag & PFRULE_FRAGMENT_NOREASS))
+ ) {
max = fragoff + ip_len;
/* Fully buffer all of the fragments
@@ -1203,14 +1208,20 @@
int ooff;
u_int8_t proto;
int terminal;
- int srs;
+ bool scrub_compat;
PF_RULES_RASSERT();
r = TAILQ_FIRST(pf_main_ruleset.rules[PF_RULESET_SCRUB].active.ptr);
- /* Check if there any scrub rules. Lack of scrub rules means enforced
- * packet normalization operation just like in OpenBSD. */
- srs = (r != NULL);
+ /*
+ * Check if there are any scrub rules, matching or not.
+ * Lack of scrub rules means:
+ * - enforced packet normalization operation just like in OpenBSD
+ * With scrub rules:
+ * - packet normalization is performed if there is a matching scrub rule
+ * XXX: Fragment reassembly always performed for IPv6!
+ */
+ scrub_compat = (r != NULL);
while (r != NULL) {
pf_counter_u64_add(&r->evaluations, 1);
if (pfi_kkif_match(r->kif, kif) == r->ifnot)
@@ -1235,7 +1246,7 @@
break;
}
- if (srs) {
+ if (scrub_compat) {
/* With scrub rules present IPv6 normalization happens only
* if one of rules has matched and it's not a "no scrub" rule */
if (r == NULL || r->action == PF_NOSCRUB)
diff --git a/tests/sys/netpfil/pf/Makefile b/tests/sys/netpfil/pf/Makefile
--- a/tests/sys/netpfil/pf/Makefile
+++ b/tests/sys/netpfil/pf/Makefile
@@ -13,6 +13,7 @@
forward \
fragmentation_compat \
fragmentation_pass \
+ fragmentation_no_reassembly \
get_state \
icmp \
killstate \
diff --git a/tests/sys/netpfil/pf/fragmentation_compat.sh b/tests/sys/netpfil/pf/fragmentation_compat.sh
--- a/tests/sys/netpfil/pf/fragmentation_compat.sh
+++ b/tests/sys/netpfil/pf/fragmentation_compat.sh
@@ -300,17 +300,6 @@
atf_check -s exit:0 -o ignore ping -c 1 192.0.2.2
jexec alcatraz pfctl -e
- pft_set_rules alcatraz \
- "pass out" \
- "block in" \
- "pass in inet proto icmp all icmp-type echoreq"
-
- # Single fragment passes
- atf_check -s exit:0 -o ignore ping -c 1 192.0.2.2
-
- # But a fragmented ping does not
- atf_check -s exit:2 -o ignore ping -c 1 -s 2000 192.0.2.2
-
pft_set_rules alcatraz \
"scrub in" \
"pass out" \
diff --git a/tests/sys/netpfil/pf/fragmentation_no_reassembly.sh b/tests/sys/netpfil/pf/fragmentation_no_reassembly.sh
new file mode 100644
--- /dev/null
+++ b/tests/sys/netpfil/pf/fragmentation_no_reassembly.sh
@@ -0,0 +1,130 @@
+#
+# SPDX-License-Identifier: BSD-2-Clause
+#
+# 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
+# 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 "match_full_v4" "cleanup"
+match_full_v4_head()
+{
+ atf_set descr 'Matching non-fragmented IPv4 packets'
+ atf_set require.user root
+ atf_set require.progs scapy
+}
+
+match_full_v4_body()
+{
+ setup_router_dummy_ipv4
+
+ # Sanity check.
+ ping_dummy_check_request exit:0 --ping-type=icmp
+
+ # Only non-fragmented packets are passed
+ jexec router pfctl -e
+ pft_set_rules router \
+ "pass out" \
+ "block in" \
+ "pass in inet proto icmp all icmp-type echoreq"
+ ping_dummy_check_request exit:0 --ping-type=icmp
+ ping_dummy_check_request exit:1 --ping-type=icmp --send-length=2000 --send-frag-length 1000
+}
+
+match_full_v4_cleanup()
+{
+ pft_cleanup
+}
+
+
+atf_test_case "match_fragment_v4" "cleanup"
+match_fragment_v4_head()
+{
+ atf_set descr 'Matching fragmented IPv4 packets'
+ atf_set require.user root
+ atf_set require.progs scapy
+}
+
+match_fragment_v4_body()
+{
+ setup_router_dummy_ipv4
+
+ # Sanity check.
+ ping_dummy_check_request exit:0 --ping-type=icmp
+
+ # Only fragmented packets are passed
+ pft_set_rules router \
+ "pass out" \
+ "block in" \
+ "pass in inet proto icmp fragment"
+ ping_dummy_check_request exit:1 --ping-type=icmp
+ ping_dummy_check_request exit:0 --ping-type=icmp --send-length=2000 --send-frag-length 1000
+}
+
+match_fragment_v4_cleanup()
+{
+ pft_cleanup
+}
+
+
+atf_test_case "compat_override_v4" "cleanup"
+compat_override_v4_head()
+{
+ atf_set descr 'Scrub rules override "set reassemble" for IPv4'
+ atf_set require.user root
+ atf_set require.progs scapy
+}
+
+compat_override_v4_body()
+{
+ setup_router_dummy_ipv4
+
+ # Sanity check.
+ ping_dummy_check_request exit:0 --ping-type=icmp
+
+ # The same as match_fragment_v4 but with "set reassemble yes" which
+ # is ignored because of presence of scrub rules.
+ # Only fragmented packets are passed.
+ pft_set_rules router \
+ "set reassemble yes" \
+ "no scrub" \
+ "pass out" \
+ "block in" \
+ "pass in inet proto icmp fragment"
+ ping_dummy_check_request exit:1 --ping-type=icmp
+ ping_dummy_check_request exit:0 --ping-type=icmp --send-length=2000 --send-frag-length 1000
+}
+
+compat_override_v4_cleanup()
+{
+ pft_cleanup
+}
+
+
+atf_init_test_cases()
+{
+ atf_add_test_case "match_full_v4"
+ atf_add_test_case "match_fragment_v4"
+ atf_add_test_case "compat_override_v4"
+}

File Metadata

Mime Type
text/plain
Expires
Tue, Apr 28, 5:00 PM (3 h, 33 m)
Storage Engine
blob
Storage Format
Raw Data
Storage Handle
32293472
Default Alt Text
D42355.id129408.diff (8 KB)

Event Timeline