NAME

Crypt::ARIA - Perl extension for ARIA encryption/decryption algorithm.

VERSION

version 0.004

SYNOPSIS

  use Crypt::ARIA;

  # create an object
  my $aria = Crypt::ARIA->new();
  # or,
  my $key = pack 'H*', '00112233445566778899aabbccddeeff';
  my $aria = Crypt::ARIA->new( $key );


  # set master key
  $aria->set_key( pack 'H*', '00112233445566778899aabbccddeeff' );
  # or
  # (whitespace allowed)
  $aria->set_key_hexstring( '00 11 22 33 44 55 66 77 88 99 aa bb cc dd ee ff' );


  # one block encryption/decryption
  # $plaintext and $ciphertext should be of "blocksize()" bytes.
  my $cipher = $aria->encrypt( $plain );
  my $plain  = $aria->decrypt( $cipher );

  
  # multi block encryption/decryption
  # simple ECB mode
  my $cipher    = $aria->encrypt_ecb( $plain );
  my $decrypted = $aria->decrypt_ecb( $cipher );
  # note that $decrypt may not be same as $plain, because it is appended
  # null bytes to.


  # CBC mode
  use Crypt::CBC;
  my $cbc = Crypt::CBC->new(
        -cipher => Crypt::ARIA->new()->set_key( $key ),
        -iv     => $initial_vector,
        -header => 'none';
        -padding => 'none';
    );
  my $cipher = $cbc->encrypt( $plain );
  my $plain  = $cbc->decrypt( $cipher );

DESCRIPTION

Crypt::ARIA provides an interface between Perl and ARIA implementation in C.

ARIA is a block cipher algorithm designed in South Korea. For more information about ARIA, visit links in "SEE ALSO" section.

The C portion of this module is made by researchers of ARIA and is available from the ARIA website. I had asked them and they've made sure that the code is free to use.

METHODS

new

new() method creates an object.

  my $aria = Crypt::ARIA->new();

You can give a master key as argument. The master key in ARIA should be of 16, 24, or 32 bytes.

  my $key = pack 'H*', '00112233445566778899aabbccddeeff';
  my $aria = Crypt::ARIA->new( $key );
set_key

set_key() sets a master key. This method returns the object itself.

  $aria->set_key( pack 'H*', '00112233445566778899aabbccddeeff' );
set_key_hexstring

set_key_hexstring() sets a master key. You can give a hexstring as argument. The hexstring can include whitespaces. This method returns the object itself.

  $aria->set_key_hexstring( '00 11 22 33 44 55 66 77 88 99 aa bb cc dd ee ff' );
unset_key

This method removes the master key from object and return the object itsetf.

  $aria->unset_key();
has_key

This method returns true if a master key is set, false otherwise.

encrypt

encrypt() encrypts a block of plaintext.

  my $cipher = $aria->encrypt( $plain );

$plain should be of exactly 16 bytes. It returns a ciphertext of 16 bytes. If you want to encrypt a text of different length, you have to choose the operation mode and the padding method. You may implement them by yourself or use another module for them.

Crypt::ARIA is designed to be compatible with Crypt::CBC. Therefore, you can use Crypt::CBC to use CBC mode with several padding methods.

  use Crypt::CBC;
  my $cbc = Crypt::CBC->new(
        -cipher => Crypt::ARIA->new()->set_key( $key ),
        -iv     => $initial_vector,
        -header => 'none';
        -padding => 'none';
    );
  my $cipher = $cbc->encrypt( $plain );
  my $plain  = $cbc->decrypt( $cipher );
decrypt

decrypt() decrypts a block of ciphertext.

  my $plain  = $aria->decrypt( $cipher );

$cipher should be of exactly 16 bytes. Again, you have to use another module to decrypt multi-block message.

encrypt_ecb

This method encrypts a plaintext of arbitrary length.

  my $cipher  = $aria->encrypt_ecb( $plain );

It returns the ciphertext whose length is multiple of 16 bytes.

NOTE: If the length of $plain is not n-times of 16 exactly, encrypt_ecb() appends null bytes to fill it. If the length is n-times of 16 exactly, $plain would be untouched. This means you should have to deliver the original length of $plain to the receiver. You had better use other module like Crypt::CBC that provides advanced operation mode and padding method. This method is just for test purpose.

decrypt_ecb

This method decrypts a multi-block ciphertext.

  my $decrypted = $aria->decrypt_ecb( $cipher );

As described in "encrypt_ecb", $decrypted may contain a sequence of null bytes in its end. You should remove them yourself.

SEE ALSO

Crypt::CBC, Crypt::SEED

http://en.wikipedia.org/wiki/ARIA_%28cipher%29

http://210.104.33.10/ARIA/index-e.html

IETF RFC 5794 : A Description of the ARIA Encryption Algorithm http://tools.ietf.org/html/rfc5794

AUTHOR

Geunyoung Park <gypark@gmail.com>

COPYRIGHT AND LICENSE

This software is copyright (c) 2013 by Geunyoung Park.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.