From 3a1f834b5228986a7c14fd60da13cf2700e80996 Mon Sep 17 00:00:00 2001 From: Doug Rabson Date: Tue, 20 Jun 2023 14:01:58 +0100 Subject: [PATCH] pf: Add code to enable filtering for locally delivered packets This is disabled by default since it potentially changes the behavior of existing filter rule sets. To enable this extra filter for packets being delivered locally, use: sysctl net.pf.filter_local=1 service pf restart PR: 268717 Reviewed-by: kp MFC-after: 2 weeks Differential Revision: https://reviews.freebsd.org/D40373 --- UPDATING | 12 ++++++++++ sys/netpfil/pf/pf_ioctl.c | 20 ++++++++++++++++ tests/sys/netpfil/common/utils.subr | 3 +-- tests/sys/netpfil/pf/fragmentation_compat.sh | 3 ++- tests/sys/netpfil/pf/fragmentation_pass.sh | 3 ++- tests/sys/netpfil/pf/killstate.sh | 24 +++++++++++++------- tests/sys/netpfil/pf/map_e.sh | 3 ++- tests/sys/netpfil/pf/pass_block.sh | 3 ++- tests/sys/netpfil/pf/pfsync.sh | 1 + tests/sys/netpfil/pf/route_to.sh | 3 ++- tests/sys/netpfil/pf/set_skip.sh | 2 +- tests/sys/netpfil/pf/table.sh | 6 +++-- 12 files changed, 65 insertions(+), 18 deletions(-) diff --git a/UPDATING b/UPDATING index 1980411c185..f4e13d97006 100644 --- a/UPDATING +++ b/UPDATING @@ -27,6 +27,18 @@ NOTE TO PEOPLE WHO THINK THAT FreeBSD 14.x IS SLOW: world, or to merely disable the most expensive debugging functionality at runtime, run "ln -s 'abort:false,junk:false' /etc/malloc.conf".) +20230619: + To enable pf rdr rules for connections initiated from the host, pf + filter rules can be optionally enabled for packets delivered + locally. This can change the behavior of rules which match packets + delivered to lo0. To enable this feature: + + sysctl net.pf.filter_local=1 + service pf restart + + When enabled, its best to ensure that packets delivered locally are not + filtered, e.g. by adding a 'skip on lo' rule. + 20230613: Improvements to libtacplus(8) mean that tacplus.conf(5) now follows POSIX shell syntax rules. This may cause TACACS+ diff --git a/sys/netpfil/pf/pf_ioctl.c b/sys/netpfil/pf/pf_ioctl.c index e76a92fb7e7..b78c30aa4b8 100644 --- a/sys/netpfil/pf/pf_ioctl.c +++ b/sys/netpfil/pf/pf_ioctl.c @@ -195,6 +195,12 @@ static MALLOC_DEFINE(M_PFRULE, "pf_rule", "pf(4) rules"); #error PF_QNAME_SIZE must be equal to PF_TAG_NAME_SIZE #endif +VNET_DEFINE_STATIC(bool, pf_filter_local) = false; +#define V_pf_filter_local VNET(pf_filter_local) +SYSCTL_BOOL(_net_pf, OID_AUTO, filter_local, CTLFLAG_VNET | CTLFLAG_RW, + &VNET_NAME(pf_filter_local), false, + "Enable filtering for packets delivered to local network stack"); + static void pf_init_tagset(struct pf_tagset *, unsigned int *, unsigned int); static void pf_cleanup_tagset(struct pf_tagset *); @@ -6682,6 +6688,13 @@ hook_pf(void) pla.pa_hook = V_pf_ip4_out_hook; ret = pfil_link(&pla); MPASS(ret == 0); + if (V_pf_filter_local) { + pla.pa_flags = PFIL_OUT | PFIL_HEADPTR | PFIL_HOOKPTR; + pla.pa_head = V_inet_local_pfil_head; + pla.pa_hook = V_pf_ip4_out_hook; + ret = pfil_link(&pla); + MPASS(ret == 0); + } #endif #ifdef INET6 pha.pa_type = PFIL_TYPE_IP6; @@ -6703,6 +6716,13 @@ hook_pf(void) pla.pa_hook = V_pf_ip6_out_hook; ret = pfil_link(&pla); MPASS(ret == 0); + if (V_pf_filter_local) { + pla.pa_flags = PFIL_OUT | PFIL_HEADPTR | PFIL_HOOKPTR; + pla.pa_head = V_inet6_local_pfil_head; + pla.pa_hook = V_pf_ip6_out_hook; + ret = pfil_link(&pla); + MPASS(ret == 0); + } #endif atomic_store_bool(&V_pf_pfil_hooked, true); diff --git a/tests/sys/netpfil/common/utils.subr b/tests/sys/netpfil/common/utils.subr index f4eec24618a..e354f6638b8 100644 --- a/tests/sys/netpfil/common/utils.subr +++ b/tests/sys/netpfil/common/utils.subr @@ -55,11 +55,10 @@ firewall_config() jexec ${jname} ipfw -q -f flush jexec ${jname} /bin/sh $cwd/ipfw.rule elif [ ${fw} == "pf" ]; then + jexec ${jname} sysctl net.pf.filter_local=1 jexec ${jname} pfctl -e jexec ${jname} pfctl -F all jexec ${jname} pfctl -f $cwd/pf.rule - jexec ${jname} pfilctl link -o pf:default-out inet-local - jexec ${jname} pfilctl link -o pf:default-out6 inet6-local elif [ ${fw} == "ipf" ]; then jexec ${jname} ipf -E jexec ${jname} ipf -Fa -f $cwd/ipf.rule diff --git a/tests/sys/netpfil/pf/fragmentation_compat.sh b/tests/sys/netpfil/pf/fragmentation_compat.sh index a783755e459..3e559a216b5 100644 --- a/tests/sys/netpfil/pf/fragmentation_compat.sh +++ b/tests/sys/netpfil/pf/fragmentation_compat.sh @@ -112,7 +112,8 @@ v6_body() "scrub fragment reassemble" \ "block in" \ "pass in inet6 proto icmp6 icmp6-type { neighbrsol, neighbradv }" \ - "pass in inet6 proto icmp6 icmp6-type { echoreq, echorep }" + "pass in inet6 proto icmp6 icmp6-type { echoreq, echorep }" \ + "set skip on lo" # Host test atf_check -s exit:0 -o ignore \ diff --git a/tests/sys/netpfil/pf/fragmentation_pass.sh b/tests/sys/netpfil/pf/fragmentation_pass.sh index d257de730d2..e2d28c30750 100644 --- a/tests/sys/netpfil/pf/fragmentation_pass.sh +++ b/tests/sys/netpfil/pf/fragmentation_pass.sh @@ -116,7 +116,8 @@ v6_body() "pass keep state" \ "block in" \ "pass in inet6 proto icmp6 icmp6-type { neighbrsol, neighbradv }" \ - "pass in inet6 proto icmp6 icmp6-type { echoreq, echorep }" + "pass in inet6 proto icmp6 icmp6-type { echoreq, echorep }" \ + "set skip on lo" # Host test atf_check -s exit:0 -o ignore \ diff --git a/tests/sys/netpfil/pf/killstate.sh b/tests/sys/netpfil/pf/killstate.sh index 4263938e26b..cd4eeee05a1 100644 --- a/tests/sys/netpfil/pf/killstate.sh +++ b/tests/sys/netpfil/pf/killstate.sh @@ -60,7 +60,8 @@ v4_body() jexec alcatraz pfctl -e pft_set_rules alcatraz "block all" \ - "pass in proto icmp" + "pass in proto icmp" \ + "set skip on lo" # Sanity check & establish state atf_check -s exit:0 -o ignore ${common_dir}/pft_ping.py \ @@ -126,7 +127,8 @@ v6_body() jexec alcatraz pfctl -e pft_set_rules alcatraz "block all" \ - "pass in proto icmp6" + "pass in proto icmp6" \ + "set skip on lo" # Sanity check & establish state atf_check -s exit:0 -o ignore ${common_dir}/pft_ping.py \ @@ -189,7 +191,8 @@ label_body() pft_set_rules alcatraz "block all" \ "pass in proto tcp label bar" \ - "pass in proto icmp label foo" + "pass in proto icmp label foo" \ + "set skip on lo" # Sanity check & establish state atf_check -s exit:0 -o ignore ${common_dir}/pft_ping.py \ @@ -251,7 +254,8 @@ multilabel_body() jexec alcatraz pfctl -e pft_set_rules alcatraz "block all" \ - "pass in proto icmp label foo label bar" + "pass in proto icmp label foo label bar" \ + "set skip on lo" # Sanity check & establish state atf_check -s exit:0 -o ignore ${common_dir}/pft_ping.py \ @@ -281,7 +285,8 @@ multilabel_body() fi pft_set_rules alcatraz "block all" \ - "pass in proto icmp label foo label bar" + "pass in proto icmp label foo label bar" \ + "set skip on lo" # Reestablish state atf_check -s exit:0 -o ignore ${common_dir}/pft_ping.py \ @@ -329,7 +334,8 @@ gateway_body() jexec alcatraz pfctl -e pft_set_rules alcatraz "block all" \ - "pass in reply-to (${epair}b 192.0.2.1) proto icmp" + "pass in reply-to (${epair}b 192.0.2.1) proto icmp" \ + "set skip on lo" # Sanity check & establish state # Note: use pft_ping so we always use the same ID, so pf considers all @@ -469,7 +475,8 @@ interface_body() jexec alcatraz pfctl -e pft_set_rules alcatraz "block all" \ - "pass in proto icmp" + "pass in proto icmp" \ + "set skip on lo" # Sanity check & establish state atf_check -s exit:0 -o ignore ${common_dir}/pft_ping.py \ @@ -525,7 +532,8 @@ id_body() pft_set_rules alcatraz "block all" \ "pass in proto tcp" \ - "pass in proto icmp" + "pass in proto icmp" \ + "set skip on lo" # Sanity check & establish state atf_check -s exit:0 -o ignore ${common_dir}/pft_ping.py \ diff --git a/tests/sys/netpfil/pf/map_e.sh b/tests/sys/netpfil/pf/map_e.sh index ce0e567ae3c..ea8ce33bf32 100644 --- a/tests/sys/netpfil/pf/map_e.sh +++ b/tests/sys/netpfil/pf/map_e.sh @@ -66,7 +66,8 @@ map_e_body() pft_set_rules echo "block return all" \ "pass in on ${epair_echo}b inet proto tcp from 198.51.100.1 port 19720:19723 to (${epair_echo}b) port 7" \ "pass in on ${epair_echo}b inet proto tcp from 198.51.100.1 port 36104:36107 to (${epair_echo}b) port 7" \ - "pass in on ${epair_echo}b inet proto tcp from 198.51.100.1 port 52488:52491 to (${epair_echo}b) port 7" + "pass in on ${epair_echo}b inet proto tcp from 198.51.100.1 port 52488:52491 to (${epair_echo}b) port 7" \ + "set skip on lo" i=0 while [ ${i} -lt ${NC_TRY_COUNT} ] diff --git a/tests/sys/netpfil/pf/pass_block.sh b/tests/sys/netpfil/pf/pass_block.sh index 0f034b23a73..2a226f5c965 100644 --- a/tests/sys/netpfil/pf/pass_block.sh +++ b/tests/sys/netpfil/pf/pass_block.sh @@ -230,7 +230,8 @@ urpf_body() --replyif ${epair_one}a pft_set_rules alcatraz \ - "block quick from urpf-failed" + "block quick from urpf-failed" \ + "set skip on lo" jexec alcatraz pfctl -e # Correct source still works diff --git a/tests/sys/netpfil/pf/pfsync.sh b/tests/sys/netpfil/pf/pfsync.sh index 75788eed4bb..1b61ec4f03a 100644 --- a/tests/sys/netpfil/pf/pfsync.sh +++ b/tests/sys/netpfil/pf/pfsync.sh @@ -152,6 +152,7 @@ defer_body() route add -net 203.0.113.0/24 198.51.100.1 # Enable pf + jexec alcatraz sysctl net.pf.filter_local=0 jexec alcatraz pfctl -e pft_set_rules alcatraz \ "set skip on ${epair_sync}a" \ diff --git a/tests/sys/netpfil/pf/route_to.sh b/tests/sys/netpfil/pf/route_to.sh index 203d0a944a5..18e0e02db65 100644 --- a/tests/sys/netpfil/pf/route_to.sh +++ b/tests/sys/netpfil/pf/route_to.sh @@ -230,7 +230,8 @@ multiwanlocal_body() "block in" \ "block out" \ "pass out quick route-to (${epair_cl_two}a 203.0.113.129) inet proto tcp from 203.0.113.128 to any port 7" \ - "pass out on ${epair_cl_one}a inet proto tcp from any to any port 7" + "pass out on ${epair_cl_one}a inet proto tcp from any to any port 7" \ + "set skip on lo" # This should work result=$(jexec client nc -N -w 1 192.0.2.2 7 | wc -c) diff --git a/tests/sys/netpfil/pf/set_skip.sh b/tests/sys/netpfil/pf/set_skip.sh index 9b3d655a6d1..c666622e3d1 100644 --- a/tests/sys/netpfil/pf/set_skip.sh +++ b/tests/sys/netpfil/pf/set_skip.sh @@ -101,7 +101,7 @@ set_skip_dynamic_body() vnet_mkjail alcatraz jexec alcatraz pfctl -e pft_set_rules alcatraz "set skip on epair" \ - "block" + "block on ! lo" epair=$(vnet_mkepair) ifconfig ${epair}a 192.0.2.2/24 up diff --git a/tests/sys/netpfil/pf/table.sh b/tests/sys/netpfil/pf/table.sh index 64dbd3a3620..b820d0c11e7 100644 --- a/tests/sys/netpfil/pf/table.sh +++ b/tests/sys/netpfil/pf/table.sh @@ -52,7 +52,8 @@ v4_counters_body() "table counters { 192.0.2.1 }" \ "block all" \ "pass in from to any" \ - "pass out from any to " + "pass out from any to " \ + "set skip on lo" atf_check -s exit:0 -o ignore ping -c 3 192.0.2.2 @@ -91,7 +92,8 @@ v6_counters_body() "table counters { 2001:db8:42::1 }" \ "block all" \ "pass in from to any" \ - "pass out from any to " + "pass out from any to " \ + "set skip on lo" atf_check -s exit:0 -o ignore ping -6 -c 3 2001:db8:42::2