Changes IP address CIDRs to varnish vcl regex.

cidr2varnish.pl

#!/usr/env/perl

use strict;
use warnings;

use Net::Netmask;
use Regexp::Assemble::Compressed;

print "Enter the filename to varnishize: ";
my $filename = <STDIN>;
chomp $filename;
exit 0 if ($filename eq "") or (! -e $filename);

my @output = ();
open (my $fh, '<', $filename) or die "cannot open < $filename : $!";
while (<$fh>) {
  # Strip it down to just numbers, dots and slashes
  $_ =~ s/[^0-9.\/]+//g;

  # Convert CIDRs to Varnish Regex
  my $block = new2 Net::Netmask ($_);
  if ($block) {
    my $first = $block->first();
    my $last = $block->last();
    my @regex = ();

    my @firstarray = split(/\./, $first);
    my @lastarray = split(/\./, $last);

    foreach my $index (0 .. $#firstarray) {
      if ($firstarray[$index] == $lastarray[$index]) {
        push @regex, $firstarray[$index];

      }
      elsif ($firstarray[$index] == 0 && $lastarray[$index] == 255 && $index == 3) {
        push @regex, "[0-9]+";
      }
      else {
        # Split the number up into individual arrays to compare each one.
        if (length($firstarray[$index]) == length($lastarray[$index])) {
          my @firstsection = split(//, $firstarray[$index]);
          my @lastsection = split(//, $lastarray[$index]);
          my @firstclone = @firstsection;
          my @lastclone = @lastsection;

          my $ra = Regexp::Assemble::Compressed->new;
          my $startrange = join('', @firstsection);
          my $endrange = join('', @lastsection);
          my @range = $startrange .. $endrange;

          for my $part (@range) {
            $ra->add($part);
          }
          my $delicious_regex = $ra->re;
          # Varnish doesn't need the fancy ?^: so we can remove them.
          $delicious_regex =~ s/[?^:]//g;
          push @regex, $delicious_regex;
        }
      }
    }

  my $single_line = join('\.', @regex) . '$';
  print "$block => $single_line\n";
  push @output, $single_line;
  }
}
close $fh;
print "-" x 100;
print join('|', @output) . "\n";