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Name	Size	Permission
OMAC	[ DIR ]	drwxrwxrwx
Perl	[ DIR ]	drwxrwxrwx
CMAC.pm	3.13 KB	-rw-rw-rw-
HMAC.pm	2.82 KB	-rw-rw-rw-
HMAC_MD5.pm	1.09 KB	-rw-rw-rw-
HMAC_SHA1.pm	1.14 KB	-rw-rw-rw-
MD2.pm	1.33 KB	-rw-rw-rw-
OMAC1.pm	447 B	-rw-rw-rw-
OMAC2.pm	1.25 KB	-rw-rw-rw-
SHA1.pm	6.92 KB	-rw-rw-rw-
Whirlpool.pm	3.23 KB	-rw-rw-rw-

Code Editor : OMAC2.pm

package Digest::OMAC2;

use base qw(Digest::OMAC::Base);

use strict;
#use warnings;
use Carp;
use MIME::Base64;

# we still call it Lu2 even though it's actually no longer squared ;-)

sub _lu2 {
	my ( $self, $blocksize,  $L ) = @_;
	$self->_shift_lu2( $L, $self->_lu2_constant($blocksize) );
}

sub _shift_lu2 {
	my ( $self, $L, $constant ) = @_;

# used to do Bit::Vector's shift_left but that's broken
	my $unpacked = unpack("B*",$L);
	my $lsb = chop $unpacked;
	my $Lt = pack("B*", "0" . $unpacked);

if ( $lsb ) {
		return $Lt ^ $constant;
	} else {
		return $Lt;
	}
}

sub _lu2_constant {
	my ( $self, $blocksize ) = @_;

if ( $blocksize == 16 ) { # 128
		return ("\x80" . ("\x00" x 14) . "\x43");
	} elsif ( $blocksize == 8 ) { # 64
		return ("\x80" . ("\x00" x 6) . "\x0d");
	} else {
		die "Blocksize $blocksize is not supported by OMAC";
	}
}

1;
__END__

=pod

=head1 NAME

Digest::OMAC2 - OMAC 2 implementation

=head1 SYNOPSIS

use Digest::OMAC2;

my $d = Digest::OMAC2->new( $key, $cipher );

=head1 DESCRIPTION

OMAC 2 is a variant of the CMAC/OMAC 1 algorithm. The initialization routines
are slightly different. OMAC2 actually precedes OMAC1, so
L<Digest::CMAC>/L<Digest::OMAC1> is the reccomended version. Supposedly OMAC1
was more rigorously analyzed.

${this.title}

Code Editor : OMAC2.pm