Index: stable/11/contrib/blacklist/libexec/blacklistd-helper
===================================================================
--- stable/11/contrib/blacklist/libexec/blacklistd-helper	(revision 314323)
+++ stable/11/contrib/blacklist/libexec/blacklistd-helper	(revision 314324)
@@ -1,126 +1,129 @@
 #!/bin/sh
 #echo "run $@" 1>&2
 #set -x
 # $1 command
 # $2 rulename
 # $3 protocol
 # $4 address
 # $5 mask
 # $6 port
 # $7 id
 
 pf=
 if [ -f "/etc/ipfw-blacklist.rc" ]; then
 	pf="ipfw"
 	. /etc/ipfw-blacklist.rc
 	ipfw_offset=${ipfw_offset:-2000}
 fi
 
 if [ -z "$pf" ]; then
 	for f in npf pf ipf; do
 		if [ -f "/etc/$f.conf" ]; then
 		    pf="$f"
 		    break
 		fi
 	done
 fi
 
 if [ -z "$pf" ]; then
 	echo "$0: Unsupported packet filter" 1>&2
 	exit 1
 fi
 
 if [ -n "$3" ]; then
 	proto="proto $3"
 fi
 
 if [ -n "$6" ]; then
 	port="port $6"
 fi
 
 addr="$4"
 mask="$5"
 case "$4" in
 ::ffff:*.*.*.*)
 	if [ "$5" = 128 ]; then
 		mask=32
 		addr=${4#::ffff:}
 	fi;;
 esac
 
 case "$1" in
 add)
 	case "$pf" in
 	ipf)
 		/sbin/ipfstat -io | /sbin/ipf -I -f - >/dev/null 2>&1
 		echo block in quick $proto from $addr/$mask to \
 		    any port=$6 head port$6 | \
 		    /sbin/ipf -I -f - -s >/dev/null 2>&1 && echo OK
 		;;
 	ipfw)
 		# use $ipfw_offset+$port for rule number
 		rule=$(($ipfw_offset + $6))
 		tname="port$6"
 		/sbin/ipfw table $tname create type addr 2>/dev/null
 		/sbin/ipfw -q table $tname add "$addr/$mask"
-		/sbin/ipfw -q add $rule drop $3 from "table("$tname")" to \
-		    any dst-port $6 && echo OK
+		# if rule number $rule does not already exist, create it
+		/sbin/ipfw show $rule >/dev/null 2>&1 || \
+			/sbin/ipfw add $rule drop $3 from \
+			table"("$tname")" to any dst-port $6 >/dev/null && \
+			echo OK
 		;;
 	npf)
 		/sbin/npfctl rule "$2" add block in final $proto from \
 		    "$addr/$mask" to any $port
 		;;
 	pf)
 		# if the filtering rule does not exist, create it
 		/sbin/pfctl -a "$2/$6" -sr 2>/dev/null | \
 		    grep -q "<port$6>" || \
 		    echo "block in quick $proto from <port$6> to any $port" | \
 		    /sbin/pfctl -a "$2/$6" -f -
 		# insert $ip/$mask into per-protocol/port anchored table
 		/sbin/pfctl -a "$2/$6" -t "port$6" -T add "$addr/$mask" && \
 		    echo OK
 		;;
 	esac
 	;;
 rem)
 	case "$pf" in
 	ipf)
 		/sbin/ipfstat -io | /sbin/ipf -I -f - >/dev/null 2>&1
 		echo block in quick $proto from $addr/$mask to \
 		    any port=$6 head port$6 | \
 		    /sbin/ipf -I -r -f - -s >/dev/null 2>&1 && echo OK
 		;;
 	ipfw)
 		/sbin/ipfw table "port$6" delete "$addr/$mask" 2>/dev/null && \
 		    echo OK
 		;;
 	npf)
 		/sbin/npfctl rule "$2" rem-id "$7"
 		;;
 	pf)
 		/sbin/pfctl -a "$2/$6" -t "port$6" -T delete "$addr/$mask" && \
 		    echo OK
 		;;
 	esac
 	;;
 flush)
 	case "$pf" in
 	ipf)
 		/sbin/ipf -Z -I -Fi -s > /dev/null && echo OK
 		;;
 	ipfw)
 		/sbin/ipfw table "port$6" flush 2>/dev/null && echo OK
 		;;
 	npf)
 		/sbin/npfctl rule "$2" flush
 		;;
 	pf)
 		/sbin/pfctl -a "$2/$6" -t "port$6" -T flush && echo OK
 		;;
 	esac
 	;;
 *)
 	echo "$0: Unknown command '$1'" 1>&2
 	exit 1
 	;;
 esac