File Coverage

blib/lib/Net/SSH/Perl/Cipher/DES3.pm

Criterion	Covered	Total	%
statement	38	59	64.4
branch	6	14	42.8
condition	2	3	66.6
subroutine	11	19	57.8
pod	3	6	50.0
total	60	101	59.4

# $Id: DES3.pm,v 1.10 2001/05/02 21:58:23 btrott Exp $

package Net::SSH::Perl::Cipher::DES3;

use strict;
use warnings;

use Net::SSH::Perl::Cipher;
use base qw( Net::SSH::Perl::Cipher );

use Net::SSH::Perl::Cipher::CBC;
use Crypt::Cipher::DES;

sub new {
    my $class = shift;
    my $ciph = bless { }, $class;
    $ciph->init(@_) if @_;
    $ciph;
}

sub keysize { 24 }
sub blocksize { 8 }

sub init {
    my $ciph = shift;
    my($key, $iv, $is_ssh2) = @_;
    $ciph->{is_ssh2} = defined $is_ssh2 ? $is_ssh2 : 0;

    if ($is_ssh2) {
        my $ede3 = Net::SSH::Perl::Cipher::DES3::EDE3->new($key);
        $ciph->{cbc} = Net::SSH::Perl::Cipher::CBC->new($ede3,
            substr($iv, 0, 8));
    }
    else {
        for my $i (1..3) {
            my $this_key = $i == 3 && length($key) <= 16 ?
                substr $key, 0, 8 :
                substr $key, 8*($i-1), 8;
            $ciph->{"cbc$i"} = Net::SSH::Perl::Cipher::CBC->new(
                Crypt::Cipher::DES->new($this_key)
            );
        }
    }
}

sub encrypt {
    my($ciph, $text) = @_;
    if ($ciph->{is_ssh2}) {
        return $ciph->{cbc}->encrypt($text);
    }
    else {
        return $ciph->{cbc3}->encrypt(
            $ciph->{cbc2}->decrypt(
                $ciph->{cbc1}->encrypt($text)
            )
        );
    }
}

sub decrypt {
    my($ciph, $text) = @_;
    if ($ciph->{is_ssh2}) {
        return $ciph->{cbc}->decrypt($text);
    }
    else {
        return $ciph->{cbc1}->decrypt(
            $ciph->{cbc2}->encrypt(
                $ciph->{cbc3}->decrypt($text)
            )
        );
    }
}

package Net::SSH::Perl::Cipher::DES3::EDE3;
use strict;

sub new {
    my $class = shift;
    my $ede3 = bless {}, $class;
    $ede3->init(@_) if @_;
    $ede3;
}

sub keysize { 24 }
sub blocksize { 8 }

sub init {
    my $ede3 = shift;
    my($key) = @_;
    for my $i (1..3) {
        my $k = substr $key, 8*($i-1), 8;
        $ede3->{"des$i"} = Crypt::Cipher::DES->new($k);
    }
}

sub encrypt {
    my($ede3, $block) = @_;
    $ede3->{des3}->encrypt(
        $ede3->{des2}->decrypt(
            $ede3->{des1}->encrypt($block)
        )
    );
}

sub decrypt {
    my($ede3, $block) = @_;
    $ede3->{des1}->decrypt(
        $ede3->{des2}->encrypt(
            $ede3->{des3}->decrypt($block)
        )
    );
}

1;
__END__