NAME

Crypt::Misty1 - Crypt::CBC-compliant block cipher

ABSTRACT

Misty1 is a 128-bit key, 64-bit block cipher. Designed by Mitsuru Matsui, the inventor of linear cryptanalysis, Misty1 is the first cipher that is provably secure against linear and differential cryptanalysis.

SYNOPSIS

    use Crypt::Misty1;

    $cipher = new Crypt::Misty1 $key;
    $ciphertext = $cipher->encrypt($plaintext);
    $plaintext  = $cipher->decrypt($ciphertext);

DESCRIPTION

Misty1 is a 64-bit symmetric block cipher with a 128-bit key. It was developed by Mitsuru Matsui, and is described in the paper New Block Encryption Algorithm MISTY and in RFC2994.

In January of 2000, the 3GPP consortium selected a variant of Misty1, dubbed as KASUMI (the Japanese word for ``misty''), as the mandatory cipher in W-CDMA.

This module supports the Crypt::CBC interface, with the following functions.

Functions

blocksize: Returns the size (in bytes) of the block (8, in this case).
keysize: Returns the size (in bytes) of the key (16, in this case).
encrypt($data): Encrypts 8 bytes of $data and returns the corresponding ciphertext.
decrypt($data): Decrypts 8 bytes of $data and returns the corresponding plaintext.

EXAMPLE 1

    #!/usr/local/bin/perl

    use diagnostics;
    use strict;
    use warnings;
    use Crypt::Misty1;

    # key must be 16 bytes long
    my $key = "0123456789abcdef";

    my $cipher = new Crypt::Misty1 $key;

    print "blocksize = ", $cipher->blocksize, " bytes \n";
    print "keysize = ", $cipher->keysize, " bytes \n";

    # block must be 8 bytes long
    my $plaintext1 = "Testing1";

    my $ciphertext = $cipher->encrypt($plaintext1);
    my $plaintext2 = $cipher->decrypt($ciphertext);

    print "Decryption OK\n" if ($plaintext1 eq $plaintext2);

EXAMPLE 2

    #!/usr/local/bin/perl

    use diagnostics;
    use strict;
    use warnings;
    use Crypt::CBC;  # CBC automatically loads Misty1 for us

    # when using Crypt::CBC, key may be of ANY length
    my $key = "0123456789abcdef";

    # IV must be exactly 8 bytes long
    my $IV = pack "H16", 0;

    my $cipher = Crypt::CBC->new({'key' => $key,
                                  'cipher' => 'Misty1',
                                  'iv' => $IV,
                                  'regenerate_key' => 1,
                                  'padding' => 'standard',
                                  'prepend_iv' => 0
                                });

    # when using Crypt::CBC, plaintext may be of ANY length
    my $plaintext1 = "This is a test";

    my $ciphertext = $cipher->encrypt($plaintext1);
    my $plaintext2 = $cipher->decrypt($ciphertext);

    print "Decryption OK\n" if ($plaintext1 eq $plaintext2);

MORE EXAMPLES

See Crypt::CBC for more examples using CBC mode. See also the ``examples'' and ``t'' directories for some more examples.

COPYRIGHT AND LICENSE

This library is free software; you can redistribute it and/or modify it under the same terms as the GNU General Public License.

Crypt::Misty1 - Crypt::CBC-compliant block cipher