CIDR to IP Script - TheGetch/Penetration-Testing-Methodology GitHub Wiki
CIDR to IP Script
./cidr-to-ip.sh [OPTION(only one)] [STRING/FILENAME] > Output.txt
-h Displays this help screen -f Forces a check for network boundary when given a STRING(s) -i Will read from an Input file (file should contain one CIDR per line) (no network boundary check) -b Will do the same as –i but with network boundary check
./cidr-to-ip.sh 192.168.0.1/24 ./cidr-to-ip.sh 192.168.0.1/24 10.10.0.0/28 ./cidr-to-ip.sh -f 192.168.0.0/16 ./cidr-to-ip.sh -i inputfile.txt ./cidr-to-ip.sh -b inputfile.txt
#!/bin/bash
############################
## Methods
############################
prefix_to_bit_netmask() {
prefix=$1;
shift=$(( 32 - prefix ));
bitmask=""
for (( i=0; i < 32; i++ )); do
num=0
if [ $i -lt $prefix ]; then
num=1
fi
space=
if [ $(( i % 8 )) -eq 0 ]; then
space=" ";
fi
bitmask="${bitmask}${space}${num}"
done
echo $bitmask
}
bit_netmask_to_wildcard_netmask() {
bitmask=$1;
wildcard_mask=
for octet in $bitmask; do
wildcard_mask="${wildcard_mask} $(( 255 - 2#$octet ))"
done
echo $wildcard_mask;
}
check_net_boundary() {
net=$1;
wildcard_mask=$2;
is_correct=1;
for (( i = 1; i <= 4; i++ )); do
net_octet=$(echo $net | cut -d '.' -f $i)
mask_octet=$(echo $wildcard_mask | cut -d ' ' -f $i)
if [ $mask_octet -gt 0 ]; then
if [ $(( $net_octet&$mask_octet )) -ne 0 ]; then
is_correct=0;
fi
fi
done
echo $is_correct;
}
#######################
## MAIN
#######################
OPTIND=1;
getopts "fibh" force;
shift $((OPTIND-1))
if [ $force = 'h' ]; then
echo ""
echo -e "THIS SCRIPT WILL EXPAND A CIDR ADDRESS.\n\nSYNOPSIS\n ./cidr-to-ip.sh [OPTION(only one)] [STRING/FILENAME]\nDESCRIPTION\n -h Displays this help screen\n -f Forces a check for network boundary when given a STRING(s)\n -i Will read from an Input file (no network boundary check)\n -b Will do the same as –i but with network boundary check\n\nEXAMPLES\n ./cidr-to-ip.sh 192.168.0.1/24\n ./cidr-to-ip.sh 192.168.0.1/24 10.10.0.0/28\n ./cidr-to-ip.sh -f 192.168.0.0/16\n ./cidr-to-ip.sh -i inputfile.txt\n ./cidr-to-ip.sh -b inputfile.txt\n"
exit
fi
if [ $force = 'i' ] || [ $force = 'b' ]; then
old_IPS=$IPS
IPS=$'\n'
lines=($(cat $1)) # array
IPS=$old_IPS
else
lines=$@
fi
for ip in ${lines[@]}; do
net=$(echo $ip | cut -d '/' -f 1);
prefix=$(echo $ip | cut -d '/' -f 2);
do_processing=1;
bit_netmask=$(prefix_to_bit_netmask $prefix);
wildcard_mask=$(bit_netmask_to_wildcard_netmask "$bit_netmask");
is_net_boundary=$(check_net_boundary $net "$wildcard_mask");
if [ $force = 'f' ] && [ $is_net_boundary -ne 1 ] || [ $force = 'b' ] && [ $is_net_boundary -ne 1 ] ; then
read -p "Not a network boundary! Continue anyway (y/N)? " -n 1 -r
echo ## move to a new line
if [[ $REPLY =~ ^[Yy]$ ]]; then
do_processing=1;
else
do_processing=0;
fi
fi
if [ $do_processing -eq 1 ]; then
str=
for (( i = 1; i <= 4; i++ )); do
range=$(echo $net | cut -d '.' -f $i)
mask_octet=$(echo $wildcard_mask | cut -d ' ' -f $i)
if [ $mask_octet -gt 0 ]; then
range="{$range..$(( $range | $mask_octet ))}";
fi
str="${str} $range"
done
ips=$(echo $str | sed "s, ,\\.,g"); ## replace spaces with periods, a join...
eval echo $ips | tr ' ' '\n'
else
exit
fi
done