#!/usr/bin/perl -w
package NetAddr::IP;
require 5.005_62;
use Carp;
use Socket;
use strict;
use warnings;
use overload
'""' => sub { $_[0]->cidr(); },
'eq' => sub { my $a = ref $_[0] eq 'NetAddr::IP' ?
$_[0]->cidr : $_[0];
my $b = ref $_[1] eq 'NetAddr::IP' ?
$_[1]->cidr : $_[1];
$a eq $b;
},
'==' => sub { return 0 unless ref $_[0] eq 'NetAddr::IP';
return 0 unless ref $_[1] eq 'NetAddr::IP';
$_[0]->cidr eq $_[1]->cidr;
},
'@{}' => sub { return [ $_[0]->hostenum ]; };
our $VERSION = '3.02';
# Preloaded methods go here.
# This is a variant to ->new() that
# creates and blesses a new object
# without the fancy parsing of
# IP formats and shorthands.
sub _fnew ($$) {
my $type = shift;
my $class = ref($type) || $type || "NetAddr::IP";
my $r_addr = shift;
return
bless { addr => $r_addr->[0],
mask => $r_addr->[1],
bits => $r_addr->[2] },
$class;
}
# Returns 2 ** $bits -1 (ie,
# $bits one bits)
sub _ones ($) {
my $bits = shift;
return ~vec('', 0, $bits);
}
sub masklen ($) {
my $self = shift;
my $bits = 0;
for (my $i = 0;
$i < $self->{bits};
$i ++)
{
$bits += vec($self->{mask}, $i, 1);
}
return $bits;
}
sub _parse_mask ($$) {
my $mask = shift;
my $bits = shift;
my $bmask = '';
if ($mask =~ m/^default$/i) {
vec($bmask, 0, $bits) = 0x0;
}
elsif ($mask =~ m/^broadcast$/i) {
vec($bmask, 0, $bits) = _ones $bits;
}
elsif ($mask =~ m/^loopback$/i) {
vec($bmask, 0, 8) = 255;
}
elsif ($mask =~ m/^(\d+)\.(\d+)\.(\d+)\.(\d+)$/) {
vec($bmask, 0, 8) = $1;
vec($bmask, 1, 8) = $2;
vec($bmask, 2, 8) = $3;
vec($bmask, 3, 8) = $4;
}
elsif ($mask =~ m/^(\d+)$/ and $1 <= 32) {
if ($1) {
vec($bmask, 0, $bits) = _ones $bits;
vec($bmask, 0, $bits) <<= ($bits - $1);
} else {
vec($bmask, 0, $bits) = 0x0;
}
}
elsif ($mask =~ m/^(\d+)$/) {
vec($bmask, 0, $bits) = $1;
}
return $bmask;
}
sub _v4 ($$) {
my $ip = shift;
my $mask = shift;
my $addr = '';
if ($ip =~ m!^default$!i) {
vec($addr, 0, 32) = 0x0;
}
elsif ($ip =~ m!^broadcast$!i) {
vec($addr, 0, 32) = _ones 32;
}
elsif ($ip =~ m!^loopback$!i) {
vec($addr, 0, 8) = 127;
vec($addr, 3, 8) = 1;
}
elsif ($ip =~ m/^(\d+)\.(\d+)\.(\d+)\.(\d+)$/) {
vec($addr, 0, 8) = $1;
vec($addr, 1, 8) = $2;
vec($addr, 2, 8) = $3;
vec($addr, 3, 8) = $4;
}
elsif ($ip =~ m/^(\d+)\.(\d+)$/) {
vec($addr, 0, 8) = $1;
vec($addr, 1, 8) = 0;
vec($addr, 2, 8) = 0;
vec($addr, 3, 8) = $2;
}
elsif ($ip =~ m/^(\d+)\.(\d+)\.(\d+)$/) {
vec($addr, 0, 8) = $1;
vec($addr, 1, 8) = $2;
vec($addr, 2, 8) = 0;
vec($addr, 3, 8) = $3;
}
elsif ($ip =~ m/^([xb\d]+)$/) {
vec($addr, 0, 32) = $1;
}
elsif (my $a = gethostbyname($ip)) {
if (inet_ntoa($a) =~ m!^(\d+)\.(\d+)\.(\d+)\.(\d+)$!) {
vec($addr, 0, 8) = $1;
vec($addr, 1, 8) = $2;
vec($addr, 2, 8) = $3;
vec($addr, 3, 8) = $4;
}
}
else {
croak "Cannot obtain an IP address out of $ip";
}
return { addr => $addr, mask => $mask, bits => 32 };
}
sub new ($$;$) {
my $type = $_[0];
my $class = ref($type) || $type || "NetAddr::IP";
my $ip = $_[1];
my $mask;
$ip = 'default' unless defined $ip;
if (@_ == 2) {
if ($ip =~ m!^(.+)/(.+)$!) {
$ip = $1;
$mask = $2;
}
elsif ($ip =~ m!^(default|broadcast|loopback)$!) {
$mask = $ip;
}
}
if (defined $_[2]) {
$mask = _parse_mask $_[2], 32;
}
elsif (defined $mask) {
$mask = _parse_mask $mask, 32;
}
else {
$mask = _parse_mask 32, 32;
}
return bless _v4($ip, $mask), $class;
}
sub new4 ($$;$) {
new($_[0], $_[1], $_[2]);
}
# Output a vec() as a dotted-quad
sub _to_quad ($) {
my $vec = shift;
return vec($vec, 0, 8) . '.' .
vec($vec, 1, 8) . '.' .
vec($vec, 2, 8) . '.' .
vec($vec, 3, 8);
}
# Get the network address
sub _network ($) {
my $self = shift;
my $a = $self->{addr};
my $m = $self->{mask};
return [ "$a" & "$m", $self->{mask}, $self->{bits} ];
}
# Should be obvious
sub _broadcast ($) {
my $self = shift;
my $a = $self->{addr};
my $m = $self->{mask};
return [ "$a" | ~ "$m", $self->{mask}, $self->{bits} ];
}
# This will become an lvalue later
sub mask ($) {
my $self = shift;
_to_quad $self->{mask};
}
# idem
sub addr ($) {
my $self = shift;
_to_quad $self->{addr};
}
sub cidr ($) {
my $self = shift;
return $self->addr . '/' . $self->masklen;
}
sub broadcast ($) {
my $self = shift;
return $self->_fnew($self->_broadcast);
}
sub network ($) {
my $self = shift;
return $self->_fnew($self->_network);
}
sub numeric ($) {
my $self = shift;
return
wantarray() ? ( vec($self->{addr}, 0, 32),
vec($self->{mask}, 0, 32) ) :
vec($self->{addr}, 0, 32);
}
# Return the shortest possible subnet
# list that completely contains all
# the given addresses or subnets.
sub compactref ($) {
my @addr = sort
{ (vec($a->{addr}, 0, $a->{bits}) <=> vec($b->{addr}, 0, $a->{bits}))
|| (vec($a->{mask}, 0, $a->{bits})
<=> vec($b->{mask}, 0, $a->{bits}))
} @{$_[0]} or
return [];
my $bits = $addr[0]->{bits};
my $changed;
do {
$changed = 0;
for (my $i = 0;
$i <= $#addr - 1;
$i ++)
{
my $lip = $addr[$i];
my $hip = $addr[$i + 1];
if ($lip->contains($hip)) {
splice(@addr, $i + 1, 1);
++ $changed;
-- $i;
}
elsif (vec($lip->{mask}, 0, $bits)
== vec($hip->{mask}, 0, $bits))
{
my $la = $lip->{addr};
my $ha = $hip->{addr};
my $nb = '';
my $na = '';
my $nm = '';
vec($nb, 0, $bits) =
vec($na, 0, $bits) =
vec($la, 0, $bits);
vec($nb, 0, $bits) ^= vec($ha, 0, $bits);
vec($na, 0, $bits) ^= vec($nb, 0, $bits);
vec($nm, 0, $bits) = vec($lip->{mask}, 0, $bits);
vec($nm, 0, $bits) <<= 1;
# if ((vec($la, 0, $bits) & vec($nm, 0, $bits))
# == (vec($ha, 0, $bits) & vec($nm, 0, $bits)))
if (("$la" & "$nm") eq ("$ha" & "$nm"))
{
if ("$la" eq "$ha") {
splice(@addr, $i + 1, 1);
}
else {
$addr[$i] = ($lip->_fnew([ "$na" & "$nm",
$nm, $bits ]));
splice(@addr, $i + 1, 1);
}
# print $lip->addr, "/", $lip->mask, " + ", $hip->addr,
# "/", $hip->mask, " = ", $addr[$i]->addr, "/",
# $addr[$i]->mask, "\n";
-- $i;
++ $changed;
}
}
}
} while ($changed);
return \@addr;
}
sub compact {
return @{compactref(\@_)};
}
# Splits the current object in
# smaller subnets, of $bits bits
# netmask.
sub splitref ($;$) {
my $self = shift;
my $mask = _parse_mask shift || $self->{bits}, $self->{bits};
my $bits = $self->{bits};
my @ret;
if (vec($self->{mask}, 0, $bits)
<= vec($mask, 0, $bits))
{
my $delta = '';
my $num = '';
my $v = '';
vec($num, 0, $bits) = _ones $bits;
vec($num, 0, $bits) ^= vec($mask, 0, $bits);
vec($num, 0, $bits) ++;
vec($delta, 0, $bits) = (vec($self->{mask}, 0, $bits)
^ vec($mask, 0, $bits));
my $net = $self->network->{addr};
$net = "$net" & "$mask";
my $to = $self->broadcast->{addr};
$to = "$to" & "$mask";
# XXX - Note that most likely,
# this loop will NOT work on IPv6...
# $net, $to and $num might very well
# be too large for most integer or
# floating pointrepresentations.
for (my $i = vec($net, 0, $bits);
$i <= vec($to, 0, $bits);
$i += vec($num, 0, $bits))
{
vec($v, 0, $bits) = $i;
push @ret, $self->_fnew([ $v, $mask, $bits ]);
}
}
return \@ret;
}
sub split ($;$) {
return @{$_[0]->splitref($_[1])};
}
sub hostenumref ($) {
my $r = $_[0]->splitref(32);
if ($_[0]->mask ne '255.255.255.255') {
splice(@$r, 0, 1);
splice(@$r, scalar @$r - 1, 1);
}
return $r;
}
sub hostenum ($) {
return @{$_[0]->hostenumref};
}
# Returns TRUE if $a completely
# contains $b and both are of the
# same length (ie, V4 or V6).
sub contains ($$) {
my $a = shift;
my $b = shift;
my $bits = $a->{bits};
my $mask;
# Both must be of the same length...
return undef
unless $bits == $b->{bits};
# $a must be less specific than $b...
return 0
unless ($mask = vec($a->{mask}, 0, $bits))
<= vec($b->{mask}, 0, $bits);
# A default address always contains
return 1 if ($mask == 0x0);
return
((vec($a->{addr}, 0, $bits) & $mask)
== (vec($b->{addr}, 0, $bits) & $mask));
}
sub within ($$) {
return contains($_[1], $_[0]);
}
sub first ($) {
my $self = shift;
my $bits = $self->{bits};
my $a = $self->{addr};
my $m = $self->{mask};
my $h = '';
my $addr = '';
vec($h, 0, $bits) = 0x1; # Turn on just the first bit
return $self->_fnew([ ("$a" & "$m") | "$h",
$self->{mask}, $bits ]);
}
sub last ($) {
my $self = shift;
my $bits = $self->{bits};
my $a = $self->{addr};
my $m = $self->{mask};
my $h = '';
my $addr = '';
vec($h, 0, $bits) = _ones $bits;
return $self->_fnew([ ("$a" & "$m") | ("$h" & ~"$m"),
$self->{mask}, $bits ]);
}
# XXX - The constant below should be
# constructed dinamically depending on
# the address size in order to work with
# V6.
sub num ($) {
my $self = shift;
return ~vec($self->{mask}, 0, $self->{bits}) & 0xFFFFFFFF;
}
1;
__END__
=head1 NAME
NetAddr::IP - Manages IPv4 addresses and subnets
=head1 SYNOPSIS
use NetAddr::IP;
my $ip = new NetAddr::IP 'loopback';
print "The address is ", $ip->addr, " with mask ", $ip->mask, "\n" ;
if ($ip->within(new NetAddr::IP "127.0.0.0", "255.0.0.0")) {
print "Is a loopback address\n";
}
# This prints 127.0.0.1/32
print "You can also say $ip...\n";
=head1 DESCRIPTION
This module provides a number of methods useful for handling IPv4
addresses ans subnets. Hopefully, its methods are also usable for IPv6
addresses.
Methods so far include:
=over
=item C<-E<gt>new([$addr, [ $mask ]])>
This method creates a new IPv4 address with the supplied address in
C<$addr> and an optional netmask C<$mask>, which can be omitted to get
a /32 mask.
C<$addr> can be almost anything that can be resolved to an IP address
in all the notations I have seen over time. It can optionally contain
the mask in CIDR notation.
If called with no arguments, 'default' is assumed.
=item C<-E<gt>broadcast()>
Returns a new object refering to the broadcast address of a given
subnet.
=item C<-E<gt>network()>
Returns a new object refering to the network address of a given
subnet.
=item C<-E<gt>addr()>
Returns a scalar with the address part of the object as a dotted-quad.
=item C<-E<gt>mask()>
Returns a scalar with the mask as a dotted-quad.
=item C<-E<gt>masklen()>
Returns a scalar the number of one bits in the mask.
=item C<-E<gt>cidr()>
Returns a scalar with the address and mask in CIDR notation.
=item C<-E<gt>numeric()>
When called in a scalar context, will return a numeric representation
of the address part of the IP address. When called in an array
contest, it returns a list of two elements. The first element is as
described, the second element is the numeric representation of the
netmask.
=item C<$me-E<gt>contains($other)>
Returns true when C<$me> completely contains C<$other>. False is
returned otherwise and C<undef> is returned if C<$me> and C<$other>
are of different versions.
=item C<$me-E<gt>within($other)>
The complement of C<-E<gt>contains()>. Returns true when C<$me> is
completely con tained within C<$other>.
=item C<-E<gt>split($bits)>
Returns a list of objects, representing subnets of C<$bits> mask
produced by splitting the original object, which is left
unchanged. Note that C<$bits> must be longer than the original
object's mask in order for it to be splittable.
Note that C<$bits> can be given as an integer (the length of the mask)
or as a dotted-quad. If omitted, a host mask is assumed.
=item C<-E<gt>splitref($bits)>
A (faster) version of C<-E<gt>split()> that returns a reference to a
list of objects instead of a real list. This is useful when large
numbers of objects are expected.
=item C<-E<gt>hostenum()>
Returns the list of hosts within a subnet.
=item C<-E<gt>hostenumref()>
Faster version of C<-E<gt>hostenum()>, returning a reference to a list.
=item C<$me-E<gt>compact($addr1, $addr2, ...)>
Given a list of objects (including C<$me>), this method will compact
all the addresses and subnets into the largest (ie, least specific)
subnets possible that contain exactly all of the given objects.
Note that in versions prior to 3.02, if fed with the same IP subnets
multiple times, these subnets would be returned. From 3.02 on, a more
"correct" approach has been adopted and only one address would be
returned.
=item C<$me-E<gt>compactref(\@list)>
As usual, a faster version of =item C<-E<gt>compact()> that returns a
reference to a list. Note that this method takes a reference to a list
instead.
=item C<-E<gt>first()>
Returns a new object representing the first useable IP address within
the subnet (ie, the first host address).
=item C<-E<gt>last()>
Returns a new object representing the last useable IP address within
the subnet (ie, one less than the broadcast address).
=item C<-E<gt>num()>
Returns the number of useable addresses IP addresses within the
subnet, not counting the broadcast address.
=back
In addition to the methods, some functions are overloaded to ease
manipulation of the objects. The available operations are:
=over
=item B<Stringification>
An object can be used just as a string. For instance, the following code
my $ip = new NetAddr::IP 'loopback';
print "$ip\n";
Will print the string 127.0.0.1/8.
=item B<Equality>
You can test for equality with either C<eq> or C<==>.
=item B<Dereferencing as an ARRAY>
You can do something along the lines of
my $net = new NetAddr::IP $cidr_spec;
for my $ip (@$net) {
print "Host $ip is in $net\n";
}
However, note that this might generate a very large amount of items
in the list. You must be careful when doing this kind of expansion.
=back
=head2 EXPORT
None by default.
=head1 HISTORY
=over
=item 0.01
=over
=item *
original version; Basic testing and release to CPAN as
version 0.01. This is considered beta software.
=back
=item 0.02
=over
=item *
Multiple changes to fix endiannes issues. This code is now
moderately tested on Wintel and Sun/Solaris boxes.
=back
=item 0.03
=over
=item *
Added -E<gt>first and -E<gt>last methods. Version changed to 0.03.
=back
=item 1.00
=over
=item *
Implemented -E<gt>new_subnet. Version changed to 1.00.
=item *
less croak()ing when improper input is fed to the module. A
more consistent 'undef' is returned now instead to allow the
user to better handle the error.
=back
=item 1.10
=over
=item *
As per Marnix A. Van Ammers [mav6@ns02.comp.pge.com]
suggestion, changed the syntax of the loop in host_enum to
be the same of the enum method.
=item *
Fixed the MS-DOS ^M at the end-of-line problem. This should
make the module easier to use for *nix users.
=back
=item 1.20
=over
=item *
Implemented -E<gt>compact and -E<gt>expand methods.
=item *
Applying for official name
=back
=item 1.21
=over
=item *
Added -E<gt>addr_number and -E<gt>mask_bits. Currently we return
normal numbers (not BigInts). Please test this in your
platform and report any problems!
=back
=item 2.00
=over
=item *
Released under the new *official* name of NetAddr::IP
=back
=item 2.10
=over
=item *
Added support for -E<gt>new($min, $max, $bits) form
=item *
Added -E<gt>to_numeric. This helps serializing objects
=back
=item 2.20
=over
=item *
Chris Dowling reported that the sort method introduced in
v1.20 for -E<gt>expand and -E<gt>compact doesn't always return a
number under perl versions < 5.6.0. His fix was applied and
redistributed. Thanks Chris!
=item *
This module is hopefully released with no CR-LF issues!
=item *
Fixed a warning about uninitialized values during make test
=back
=item 2.21
=over
=item *
Dennis Boylan pointed out a bug under Linux and perhaps
other platforms as well causing the error "Sort subroutine
didn't return single value at
/usr/lib/perl5/site_perl/5.6.0/NetAddr/IP.pm line 299, E<lt>E<gt>
line 2." or similar. This was fixed.
=back
=item 2.22
=over
=item *
Some changes suggested by Jeroen Ruigrok and Anton Berezin
were included. Thanks guys!
=back
=item 2.23
=over
=item *
Bug fix for /XXX.XXX.XXX.XXX netmasks under v5.6.1 suggested
by Tim Wuyts. Thanks!
=item *
Tested the module under MACHTYPE=hppa1.0-hp-hpux11.00. It is
now konwn to work under Linux (Intel/AMD), Digital Unix
(Alpha), Solaris (Sun), HP-UX11 (HP-PA-RISC), Windows
9x/NT/2K (using ActiveState on Intel).
=back
=item 2.24
=over
=item *
A spurious warning when expand()ing with -w under certain
circumstances was removed. This involved using /31s, /32s
and the same netmask as the input. Thanks to Elie Rosenblum
for pointing it out.
=item *
Slight change in license terms to ease redistribution as a
Debian package.
=back
=item 3.00
=over
This is a major rewrite, supposed to fix a number of issues pointed
out in earlier versions.
The goals for this version include getting rid of BigInts, speeding up
and also cleaning up the code, which is written in a modular enough
way so as to allow IPv6 functionality in the future, taking benefit
from most of the methods.
Note that no effort has been made to remain backwards compatible with
earlier versions. In particular, certain semantics of the earlier
versions have been removed in favor of faster performance.
This version was tested under Win98/2K (ActiveState 5.6.0/5.6.1),
HP-UX11 on PA-RISC (5.6.0), RedHat Linux 6.2 (5.6.0), Digital Unix on
Alpha (5.6.0), Solaris on Sparc (5.6.0) and possibly others.
=back
=item 3.01
=over
=item *
Added C<-E<gt>numeric()>.
=item *
C<-E<gt>new()> called with no parameters creates a B<default>
NetAddr::IP object.
=back
=item 3.02
=over
=item *
Fxed C<-E<gt>compact()> for cases of equal subnets or
mutually-contained IP addresses as pointed out by Peter Wirdemo. Note
that now only distinct IP addresses will be returned by this method.
=item *
Fixed the docs as suggested by Thomas Linden.
=item *
Introduced overloading to ease certain common operations.
=item *
Fixed compatibility issue with C<-E<gt>num()> on 64-bit processors.
=back
=back
=head1 AUTHOR
Luis E. Munoz <lem@cantv.net>
=head1 WARRANTY
This software comes with the same warranty as perl itself (ie, none), so
by using it you accept any and all the liability.
=head1 LICENSE
This software is (c) Luis E. Munoz. It can be used under the terms of
the perl artistic license provided that proper credit for the work of
the author is preserved in the form of this copyright notice and
license for this module.
=head1 SEE ALSO
perl(1).
=cut
Luis Muñoz