utility module to perform repeated CIDR lookups

modules/util/Util/CIDR.pm

+#!/usr/bin/perl
+
+use strict;
+
+package Util::CIDR;
+
+use Net::CIDR;
+
+__PACKAGE__->main() unless caller();
+
+sub new
+{
+  my $class= shift;
+
+  my $self= { _cidr => {}, _ips => {} };
+  bless ($self, $class);
+  $self->set(@_);
+
+  $self;
+}
+
+sub set
+{
+  my $self= shift;
+  my %pars= @_;
+  foreach my $par (keys %pars)
+  {
+    $self->{$par}= $pars{$par};
+  }
+  $self;
+}
+
+sub add_cidr
+{
+  my $self= shift;
+  my $ip_block= shift;
+  my $comment= shift;
+
+  my $v= Net::CIDR::cidrvalidate($ip_block);
+  return undef unless (defined ($v) && $ip_block =~ m#/#);
+
+  my $cidr= $self->{_cidr};
+
+  my $b;
+  unless (defined ($b= $cidr->{$ip_block}))
+  {
+    $b= $cidr->{$ip_block}= { ip_block => $ip_block };
+  }
+
+  if ($comment)
+  {
+    # print __LINE__, " comment=[$comment] b: ", main::Dumper($b);
+    my $c;
+    unless (defined ($c= $b->{comments})) { $c= $b->{comments}= [] }
+    push (@$c => $comment);
+  }
+
+  $b;
+}
+
+sub read_cidr_list
+{
+  my $self= shift;
+  my $fnm= shift;
+
+  unless (open (FI, '<:utf8', $fnm))
+  {
+    print __LINE__, " can't read CIDR list from fnm=[$fnm]\n";
+    return 0;
+  }
+
+  my $cnt= 0;
+  L: while (defined (my $l= <FI>))
+  {
+    chop($l);
+
+    next L if ($l eq '' || $l =~ m/^#/);
+
+    my ($ip_block, $comment)= split(' ', $l, 2);
+    $self->add_cidr($ip_block, $comment);
+
+    $cnt++;
+  }
+  close(FI);
+
+  $cnt;
+}
+
+=head2 lookup
+
+lookup IP address in cidr list and return structure pointing to the IP block and counter
+
+=cut
+
+sub lookup
+{
+  my $self= shift;
+  my $ip= shift;
+
+  if (exists ($self->{_ips}->{$ip}))
+  {
+    my $x= $self->{_ips}->{$ip};
+    $x->{count}++;
+    return $x;
+  }
+
+  # not yet looked up...
+  my $x= $self->{_ips}->{$ip}= { count => 1 };
+  my $c= $self->{_cidr};
+  L: foreach my $cidr (keys %$c)
+  {
+    if (Net::CIDR::cidrlookup($ip, $cidr))
+    {
+      my $b= $c->{$cidr};
+      $x->{ip_block}= $b;
+      last;
+    }
+  }
+
+  $x;
+}
+
+sub main
+{
+  print join (' ', __FILE__, __LINE__, 'main: caller=['. caller(). ']'), "\n";
+}
+

modules/util/t_util_cidr.pl

+#!/usr/bin/perl
+
+use lib '.';
+
+use Util::CIDR;
+use Data::Dumper;
+$Data::Dumper::Indent= 1;
+$Data::Dumper::Sortkeys= 1;
+
+my $uc= Util::CIDR->new();
+
+$uc->add_cidr('111.121.0.0/16', 'blocked dv05');
+$uc->add_cidr('111.122.0.0/16', 'just looking');
+$uc->add_cidr('131.130.0.0/16', 'UNIVIE');
+$uc->add_cidr('85.208.96.0/24', 'US crawlers');
+
+foreach my $ip (qw(111.121.2.3 131.130.2.194 84.83.32.81 85.208.96.212 1.2.3.4))
+{
+  my $res= $uc->lookup($ip);
+  print __LINE__, " ip=[$ip] res: ", Dumper($res);
+}
+
+print __LINE__, " uc: ", Dumper($uc);
+
+