扫描目标网络中未使用的IP

shell scripts说明：只支持C类及其子网。

 

#!/bin/bash

read -p "Please input an ipaddr of destination network:" ip
read -p "Please input destination network mask[255.255.255.0]:" mask
if [ -z $mask ];then
   mask=255.255.255.0
fi
ip1=${ip%%.*}
tempip1=${ip#*.}
ip2=${tempip1%%.*}
tempip2=${ip%.*}
ip3=${tempip2##*.}
ip4=${ip##*.}

mask1=${mask%%.*}
tempmask1=${mask#*.}
mask2=${tempmask1%%.*}
tempmask2=${mask%.*}
mask3=${tempmask2##*.}
mask4=${mask##*.}

destip1=$((ip1 & mask1))
destip2=$((ip2 & mask2))
destip3=$((ip3 & mask3))
destip4=$((ip4 & mask4))

destbcast=$((destip4 + 255 - mask4))

echo "the network address is: $destip4"
echo "the broadcast address is: $destbcast"
echo

let count=0
for (( i=destip4+1; $i-$destbcast; i++ ));
do
   ping -c2 $ip1.$ip2.$ip3.$i > /dev/null 2>&1
   if [ $? -ne 0 ];then
      echo "you can use:$ip1.$ip2.$ip3.$i"
      ((count++))
   fi
done
echo
echo "There are $count IPs can be used"

exit 0