NAME

Net::Subnets - Computing subnets in large scale networks

SYNOPSIS

    use Net::Subnets;
    my $sn = Net::Subnets->new;
    $sn->subnets( \@subnets );
    if ( my $subnetref = $sn->check( \$address ) ) {
        ...
    }
    my ( $lowipref, highipref ) = $sn->range( \$subnet );
    my $listref = $sn->list( \( $lowipref, $highipref ) );

DESCRIPTION

Very fast matches large lists of IP addresses against many CIDR subnets and calculates IP address ranges.

The following functions are provided by this module:

    new()
        Creates an "Net::Subnets" object.
        It takes no arguments.

    subnets( \@subnets )
        The subnets() function lets you prepare a list of CIDR subnets.
        It takes an array reference.

    check( \$address )
        The check() function lets you check an IP address against the
        previously prepared subnets.
        It takes a scalar reference and returns a scalar reference to
        the first matching CIDR subnet.

    range( \$subnet )
        The range() function lets you calculate the IP address range
        of a subnet.
        It takes a scalar reference and returns two scalar references to
        the lowest and highest IP address.

    list( \$lowip, \$highip )
        The list() function lets you calculate a list containing all IP
        addresses in a given range.
        It takes two scalar references and returns a reference to a list
        containing the IP addresses.

This is a simple and efficient example for subnet matching:

    use Net::Subnets;

    my @subnets   = qw(10.0.0.0/24 10.0.1.0/24);
    my @addresses = qw(10.0.0.1 10.0.1.2 10.0.3.1);

    my $sn = Net::Subnets->new;
    $sn->subnets( \@subnets );
    my $results;
    foreach my $address ( @addresses ) {
        if ( my $subnetref = $sn->check( \$address ) ) {
            $results .= "$address: $$subnetref\n";
        }
        else {
            $results .= "$address: not found\n";
        }
    }
    print( $results );

This is a simple example for range calculation:

    use Net::Subnets;

    my @subnets = qw(10.0.0.0/24 10.0.1.0/24);

    my $sn = Net::Subnets->new;
    my $results;
    foreach my $subnet ( @subnets ) {
        my ( $lowipref, $highipref ) = $sn->range( \$subnet );
        $results .= "$subnet: $$lowipref - $$highipref\n";
    }
    print( $results );
    

This is a simple example for list generation:

    use Net::Subnets;

    my $lowip  = '192.168.0.1';
    my $highip = '192.168.0.100';

    my $sn = Net::Subnets->new;
    my $listref = $sn->list( \( $lowip, $highip ) );
    foreach my $address ( @{ $listref } ) {
        # do something cool
    }

AUTHOR

Sebastian Riedel (sri@cpan.org), Juergen Peters (juergen.peters@taulmarill.de)

COPYRIGHT

Copyright 2003 Sebastian Riedel & Juergen Peters. All rights reserved.

This library is free software. You can redistribute it and/or modify it under the same terms as perl itself.