init.d: 99-lan-filter custom script

2026-03-13 22:03:09 +00:00 · 2026-01-08 20:20:52 +03:00
parent 577959f442
commit 3ec585c97e
2 changed files with 146 additions and 1 deletions
--- a/init.d/custom.d.examples.linux/99-lan-filter
+++ b/init.d/custom.d.examples.linux/99-lan-filter
@@ -0,0 +1,145 @@
+# this custom script sets FILTER_MARK to specified source ips
+
+# NOTE !!! SCRIPT REQUIRES FILTER_MARK VAR IN CONFIG FILE !!!
+# NOTE !!! WITHOUT FILTER_MARK IT DOES NOTHING !!!
+
+# NOTE !!! ON NON-OPENWRT SYSTEMS SCRIPT REQUIRES IFACE_LAN VAR IN CONFIG FILE !!!
+
+# can override in config :
+# LAN ip/cidr list to be fooled. elements are space separated
+FILTER_LAN_IP="${FILTER_LAN_IP:-192.168.0.0/16}"
+FILTER_LAN_IP6="${FILTER_LAN_IP6:-fc00::/7}"
+# allow fooling from local system (0|1) ?
+FILTER_LAN_ALLOW_OUTPUT="${FILTER_LAN_ALLOW_OUTPUT:-1}"
+
+FILTER_LAN_SET="lanfilter"
+FILTER_LAN_SET6="${FILTER_LAN_SET}6"
+FILTER_LAN_IPSET_SIZE=${FILTER_LAN_IPSET_SIZE:-256}
+FILTER_LAN_IPSET_OPT="${FILTER_LAN_IPSET_OPT:-hash:net hashsize 8192 maxelem $FILTER_LAN_IPSET_SIZE}"
+
+filter_mark_check()
+{
+	[ -n "$FILTER_MARK" ] || {
+		echo "WARNING ! lan filter cannot work without FILTER_MARK set in config"
+		return 1
+	}
+	[ "$DISABLE_IPV4" = 1 -a "$DISABLE_IPV6" = 1 ] && return 1
+	return 0
+}
+
+zapret_custom_firewall()
+{
+	# $1 - 1 - run, 0 - stop
+
+	filter_mark_check || return
+
+	local subnet lanifs rule
+	local setmark="-j MARK --set-mark $FILTER_MARK/$FILTER_MARK"
+	local filt4="-m set --match-set $FILTER_LAN_SET src"
+	local filt6="-m set --match-set $FILTER_LAN_SET6 src"
+
+	get_lanif lanifs
+
+	[ "$DISABLE_IPV4" != 1 ] && {
+		[ "$FILTER_LAN_ALLOW_OUTPUT" = 1 ] && {
+			ipt_print_op $1 "$setmark" "filter output"
+			ipt_add_del $1 OUTPUT -t mangle $setmark
+		}
+		[ -n "$lanifs" ] && {
+			[ "$1" = 1 ] && {
+				ipset create $FILTER_LAN_SET $FILTER_LAN_IPSET_OPT family inet 2>/dev/null
+				ipset flush $FILTER_LAN_SET
+				for subnet in $FILTER_LAN_IP; do
+					echo add $FILTER_LAN_SET $subnet
+				done | ipset -! restore
+			}
+			for lan in $lanifs; do
+				rule="-i $lan $filt4 $setmark"
+				ipt_print_op $1 "$rule" "filter forward"
+				ipt_add_del $1 FORWARD -t mangle $rule
+			done
+		}
+	}
+	[ "$DISABLE_IPV6" != 1 ] && {
+		[ "$FILTER_LAN_ALLOW_OUTPUT" = 1 ] && {
+			ipt_print_op $1 "$setmark" "filter output" 6
+			ipt6_add_del $1 OUTPUT -t mangle $setmark
+		}
+		[ -n "$lanifs" ] && {
+			[ "$1" = 1 ] && {
+				ipset create $FILTER_LAN_SET6 $FILTER_LAN_IPSET_OPT family inet6 2>/dev/null
+				ipset flush $FILTER_LAN_SET6
+				for subnet in $FILTER_LAN_IP6; do
+					echo add $FILTER_LAN_SET6 $subnet
+				done | ipset -! restore
+			}
+			for lan in $lanifs; do
+				rule="-i $lan $filt6 $setmark"
+				ipt_print_op $1 "$rule" "filter forward" 6
+				ipt6_add_del $1 FORWARD -t mangle $rule
+			done
+		}
+	}
+
+	[ "$1" = 1 ] || {
+		ipset destroy $FILTER_LAN_SET 2>/dev/null
+		ipset destroy $FILTER_LAN_SET6 2>/dev/null
+	}
+}
+
+zapret_custom_firewall_nft()
+{
+	filter_mark_check || return
+
+	local subnets rule
+	local setmark="meta mark set meta mark or $FILTER_MARK"
+	local filt4="ip saddr == @$FILTER_LAN_SET"
+	local filt6="ip6 saddr == @$FILTER_LAN_SET6"
+	local lanif="iifname @lanif"
+
+	nft_add_chain forward_lan_filter "type filter hook forward priority mangle;"
+	nft_flush_chain forward_lan_filter
+
+	if [ "$FILTER_LAN_ALLOW_OUTPUT" = 1 ]; then
+		nft_add_chain output_lan_filter "type filter hook output priority mangle;"
+		nft_flush_chain output_lan_filter
+		nft_print_op "$setmark" "filter output" "4+6"
+		nft_add_rule output_lan_filter $setmark
+	else
+		nft_del_chain output_lan_filter 2>/dev/null
+	fi
+
+	[ "$DISABLE_IPV4" != 1 ] && {
+	        make_comma_list subnets $FILTER_LAN_IP
+		nft_create_set $FILTER_LAN_SET "type ipv4_addr; size $FILTER_LAN_IPSET_SIZE; auto-merge; flags interval;"
+		nft_flush_set $FILTER_LAN_SET
+		nft_add_set_element $FILTER_LAN_SET "$subnets"
+
+		rule="$lanif $filt4 $setmark"
+		nft_print_op "$rule" "filter forward" "4"
+		nft_add_rule forward_lan_filter $rule
+	}
+	[ "$DISABLE_IPV6" != 1 ] && {
+	        make_comma_list subnets $FILTER_LAN_IP6
+		nft_create_set $FILTER_LAN_SET6 "type ipv6_addr; size $FILTER_LAN_IPSET_SIZE; auto-merge; flags interval;"
+		nft_flush_set $FILTER_LAN_SET6
+		nft_add_set_element $FILTER_LAN_SET6 "$subnets"
+
+		rule="$lanif $filt6 $setmark"
+		nft_print_op "$rule" "filter forward" "6"
+		nft_add_rule forward_lan_filter $rule
+	}
+}
+
+
+zapret_custom_firewall_nft_flush()
+{
+	# this function is called after all nft fw rules are deleted
+	# however sets are not deleted. it's desired to clear sets here.
+
+	nft_del_chain forward_lan_filter 2>/dev/null
+	nft_del_chain output_lan_filter 2>/dev/null
+
+	nft_del_set $FILTER_LAN_SET 2>/dev/null
+	nft_del_set $FILTER_LAN_SET6 2>/dev/null
+}