I have an input file with IPv4 addresses:
94.228.16.0 - 94.228.25.255 94.241.136.0/24 94.241.136.0 - 94.241.136.255 94.29.128.0/17 94.29.128.0 - 94.29.191.0 94.29.192.0 - 94.29.255.0 94.74.181.0/24 94.74.181.0 - 94.74.181.31 94.74.181.128 - 94.74.181.255 How I can convert the address ranges to netmasks? The result should be:
94.228.16.0/21 94.241.136.0/24 94.241.136.0/24 94.29.128.0/17 94.29.128.0/19 94.29.192.0/19 94.74.181.0/24 94.74.181.0/27 94.74.181.128/25 2 Answers
First you will need to install a package to do the conversion
sudo apt install ipcalc Now you can do it with this little script (please note that it doesn't work if you quote the variable):
$ while read line; do if [[ $line = *-* ]]; then (ipcalc $line | sed '2!d'); else echo $line; fi; done < file 94.228.16.0/21 94.241.136.0/24 94.241.136.0/24 94.29.128.0/17 94.29.128.0/19 94.29.192.0/19 94.74.181.0/24 94.74.181.0/27 94.74.181.128/25 or more readably
while read line; do if [[ $line = *-* ]]; then (ipcalc $line | sed '2!d') else echo $line fi done < file Perhaps not surprisingly, there is a CPAN perl module Net::CIDR for this.
So for example:
$ perl -MNet::CIDR=range2cidr -lne 'print for range2cidr $_' yourfile 94.228.16.0/21 94.228.24.0/23 94.241.136.0/24 94.241.136.0/24 94.29.128.0/17 94.29.191.0/32 94.29.128.0/19 94.29.160.0/20 94.29.176.0/21 94.29.184.0/22 94.29.188.0/23 94.29.190.0/24 94.29.255.0/32 94.29.192.0/19 94.29.224.0/20 94.29.240.0/21 94.29.248.0/22 94.29.252.0/23 94.29.254.0/24 94.74.181.0/24 94.74.181.0/27 94.74.181.128/25 The module is available on Ubuntu by installing the libnet-cidr-perl package.
NB I have not validated your input or the results.
