Add small script for reverse dns enumeration of ipv4 subnets

bin/reverse-subnet.sh

@@ -0,0 +1,17 @@
+#!/bin/bash
+IP4BLOCK="$1"
+
+echo "Doing reverse lookup for $IP4BLOCK.0/24..."
+
+ctr=1
+while [ $ctr -le 255 ]; do
+	ipaddress="$IP4BLOCK.$ctr";
+	result=`dig +short -x $ipaddress`;
+	result=`echo $result | sed -e 's#\n##g'`
+	if [ "$result" != "" ]; then
+		echo "$ipaddress $result";
+	fi;
+	((ctr++));
+done
+
+