The branch main has been updated by kp: URL: https://cgit.FreeBSD.org/src/commit/?id=cdbc9b76ff4901816b5ebdca5d0b7e9947a015cb
commit cdbc9b76ff4901816b5ebdca5d0b7e9947a015cb Author: Kristof Provost <[email protected]> AuthorDate: 2025-12-15 14:26:57 +0000 Commit: Kristof Provost <[email protected]> CommitDate: 2025-12-15 16:24:34 +0000 pf: fix min-ttl and set-tos for nat64 If we have both af-to and min-ttl or set-tos on a single rule we didn't apply the new ttl or tos. That's because the scrub code still applied the change, but we subsequently create a new header for the new address family. That's done based on the ttl/tos saved in the struct pf_pdesc, which are the values from the incoming packet, before the scrub modification(s). Also update the struct pf_pdesc values when we update packets. Reported by: Marek Zarychta Sponsored by: Rubicon Communications, LLC ("Netgate") --- sys/netpfil/pf/pf_norm.c | 6 ++-- tests/sys/netpfil/pf/nat64.sh | 69 +++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 73 insertions(+), 2 deletions(-) diff --git a/sys/netpfil/pf/pf_norm.c b/sys/netpfil/pf/pf_norm.c index 53010222dd07..1362ce5387bb 100644 --- a/sys/netpfil/pf/pf_norm.c +++ b/sys/netpfil/pf/pf_norm.c @@ -2244,14 +2244,14 @@ pf_scrub(struct pf_pdesc *pd) h->ip_ttl < pd->act.min_ttl) { u_int16_t ip_ttl = h->ip_ttl; - h->ip_ttl = pd->act.min_ttl; + pd->ttl = h->ip_ttl = pd->act.min_ttl; h->ip_sum = pf_cksum_fixup(h->ip_sum, ip_ttl, h->ip_ttl, 0); } #ifdef INET6 /* Enforce a minimum ttl, may cause endless packet loops */ if (pd->af == AF_INET6 && pd->act.min_ttl && h6->ip6_hlim < pd->act.min_ttl) - h6->ip6_hlim = pd->act.min_ttl; + pd->ttl = h6->ip6_hlim = pd->act.min_ttl; #endif /* INET6 */ /* Enforce tos */ if (pd->act.flags & PFSTATE_SETTOS) { @@ -2261,6 +2261,7 @@ pf_scrub(struct pf_pdesc *pd) ov = *(u_int16_t *)h; h->ip_tos = pd->act.set_tos | (h->ip_tos & IPTOS_ECN_MASK); + pd->tos = h->ip_tos & ~IPTOS_ECN_MASK; nv = *(u_int16_t *)h; h->ip_sum = pf_cksum_fixup(h->ip_sum, ov, nv, 0); @@ -2270,6 +2271,7 @@ pf_scrub(struct pf_pdesc *pd) case AF_INET6: h6->ip6_flow &= IPV6_FLOWLABEL_MASK | IPV6_VERSION_MASK; h6->ip6_flow |= htonl((pd->act.set_tos | IPV6_ECN(h6)) << 20); + pd->tos = IPV6_DSCP(h6); break; #endif /* INET6 */ } diff --git a/tests/sys/netpfil/pf/nat64.sh b/tests/sys/netpfil/pf/nat64.sh index 6631e3eca2c7..e2a87a6eee40 100644 --- a/tests/sys/netpfil/pf/nat64.sh +++ b/tests/sys/netpfil/pf/nat64.sh @@ -1179,6 +1179,74 @@ v6_gateway_cleanup() pft_cleanup } +atf_test_case "scrub_min_ttl" "cleanup" +scrub_min_ttl_head() +{ + atf_set descr 'Ensure scrub min-ttl applies to nat64 traffic' + atf_set require.user root +} + +scrub_min_ttl_body() +{ + pft_init + + epair=$(vnet_mkepair) + epair_link=$(vnet_mkepair) + epair_link_two=$(vnet_mkepair) + + ifconfig ${epair}a inet6 2001:db8::2/64 up no_dad + route -6 add default 2001:db8::1 + + vnet_mkjail rtr ${epair}b ${epair_link}a + jexec rtr ifconfig ${epair}b inet6 2001:db8::1/64 up no_dad + jexec rtr ifconfig ${epair_link}a 192.0.2.1/24 up + jexec rtr route add default 192.0.2.2 + + vnet_mkjail rtr2 ${epair_link}b ${epair_link_two}a + jexec rtr2 ifconfig ${epair_link}b 192.0.2.2/24 up + jexec rtr2 ifconfig ${epair_link_two}a 198.51.100.2/24 up + jexec rtr2 sysctl net.inet.ip.forwarding=1 + + vnet_mkjail dst ${epair_link_two}b + jexec dst ifconfig ${epair_link_two}b 198.51.100.1/24 up + jexec dst route add default 198.51.100.2 + + # Sanity checks + atf_check -s exit:0 -o ignore \ + ping6 -c 1 2001:db8::1 + atf_check -s exit:0 -o ignore \ + jexec rtr ping -c 1 192.0.2.2 + atf_check -s exit:0 -o ignore \ + jexec rtr ping -c 1 198.51.100.2 + atf_check -s exit:0 -o ignore \ + jexec rtr ping -c 1 198.51.100.1 + + jexec rtr pfctl -e + pft_set_rules rtr \ + "pass" \ + "pass in on ${epair}b inet6 from any to 64:ff9b::/96 af-to inet from (${epair_link}a)" + + # Ping works with a normal TTL + atf_check -s exit:0 -o ignore \ + ping6 -c 1 64:ff9b::198.51.100.1 + + # If we set a TTL of two the packet gets dropped + atf_check -s exit:2 -o ignore \ + ping6 -c 1 -m 2 64:ff9b::198.51.100.1 + + # But if we have pf enforce a minimum ttl of 10 the ping does pass + pft_set_rules rtr \ + "pass" \ + "pass in on ${epair}b inet6 from any to 64:ff9b::/96 af-to inet from (${epair_link}a) scrub (min-ttl 10)" + atf_check -s exit:0 -o ignore \ + ping6 -c 1 -m 2 64:ff9b::198.51.100.1 +} + +scub_min_ttl_cleanup() +{ + pft_cleanup +} + atf_init_test_cases() { atf_add_test_case "icmp_echo_in" @@ -1206,4 +1274,5 @@ atf_init_test_cases() atf_add_test_case "route_to" atf_add_test_case "reply_to" atf_add_test_case "v6_gateway" + atf_add_test_case "scrub_min_ttl" }
