{
use strict;
use warnings;
use Carp qw[carp];
use Fcntl ':flock';
our $MAJOR = 0.074; our $MINOR = 0; our $DEV = 1; our $VERSION = sprintf('%1.3f%03d' . ($DEV ? (($DEV < 0 ? '' : '_') . '%03d') : ('')), $MAJOR, $MINOR, abs $DEV);
use vars qw[@EXPORT_OK %EXPORT_TAGS];
use Exporter qw[];
*import = *import = *Exporter::import;
@EXPORT_OK = qw[compact_ipv6 uncompact_ipv6];
%EXPORT_TAGS = (all => [@EXPORT_OK], bencode => [@EXPORT_OK]);
sub uncompact_ipv6 {
my %peers;
$peers{sprintf("%X:%X:%X:%X:%X:%X:%X:%X:%s", unpack('n9', $1))}++
while ($_[0] =~ s[^(.{18})][]g);
return keys %peers;
}
sub compact_ipv6 {
my (@peers) = @_;
@peers || return;
my $return;
my %seen;
PEER: for my $peer (grep(defined && !$seen{$_}++, @peers)) {
next if not $peer;
my ($ip, $port) = ($peer =~ m[^([\da-f:]+):(\d+)$]i);
if ($port > 2**16) {
carp 'Port number beyond ephemeral range: ' . $peer;
}
else {
next PEER unless $ip;
if ($ip
=~ /^(.*):(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})$/)
{ # mixed hex, dot-quad
next PEER if $2 > 255 || $3 > 255 || $4 > 255 || $5 > 255;
$ip = sprintf("%s:%X%02X:%X%02X", $1, $2, $3, $4, $5)
; # convert to pure hex
}
my $c;
next PEER
if $ip =~ /[^:0-9a-fA-F]/ || # non-hex character
(($c = $ip) =~ s/::/x/ && $c =~ /(?:x|:):/)
|| # double :: ::?
$ip =~ /[0-9a-fA-F]{5,}/; # more than 4 digits
$c = $ip =~ tr/:/:/; # count the colons
next PEER if $c < 7 && $ip !~ /::/;
if ($c > 7) { # strip leading or trailing ::
next PEER unless $ip =~ s/^::/:/ || $ip =~ s/::$/:/;
next PEER if --$c > 7;
}
$ip =~ s/::/:::/ while $c++ < 7; # expand compressed fields
$ip .= 0 if $ip =~ /:$/;
my @hex = split(/:/, $ip);
$hex[$_] = hex($hex[$_] || 0) foreach (0 .. $#hex);
$return .= uc pack('n9', @hex, $port);
}
}
return $return;
}
}
1;
=pod
=head1 NAME
Net::BitTorrent::Protocol::BEP07::Compact - Utility functions for BEP07: IPv6 Tracker Extension
=head1 Importing From Net::BitTorrent::Protocol::BEP07::Compact
By default, nothing is exported.
You may import any of the following or use one or more of these tag:
=over
=item C<:all>
Imports the tracker response-related functions
L<compact|/"compact_ipv6 ( LIST )"> and
L<uncompact|/"uncompact_ipv6 ( STRING )">.
=back
=head1 Functions
=over
=item C<compact_ipv6 ( LIST )>
Compacts a list of IPv6:port strings into a single string.
A compact peer is 18 bytes; the first 15 bytes are the host and the last two
bytes are the port.
=item C<uncompact_ipv6 ( STRING )>
Inflates a compacted string of peers and returns a list of IPv6:port strings.
=back
=head1 See Also
=over
=item BEP 07: IPv6 Tracker Extension
=back
=head1 Author
Sanko Robinson <sanko@cpan.org> - http://sankorobinson.com/
CPAN ID: SANKO
=head1 License and Legal
Copyright (C) 2010 by Sanko Robinson <sanko@cpan.org>
This program is free software; you can redistribute it and/or modify it under
the terms of
See the F<LICENSE> file included with this distribution or
L<notes on the Artistic License 2.0|http://www.perlfoundation.org/artistic_2_0_notes>
for clarification.
When separated from the distribution, all original POD documentation is
covered by the
L<Creative Commons Attribution-Share Alike 3.0 License|http://creativecommons.org/licenses/by-sa/3.0/us/legalcode>.
See the
L<clarification of the CCA-SA3.0|http://creativecommons.org/licenses/by-sa/3.0/us/>.
Neither this module nor the L<Author|/Author> is affiliated with BitTorrent,
Inc.
=for rcs $Id: Compact.pm a7f61f8 2010-06-27 02:13:37Z sanko@cpan.org $
=cut