package Crypt::Mode::CTR;

### BEWARE - GENERATED FILE, DO NOT EDIT MANUALLY!

use strict;
use warnings;
our $VERSION = '0.044';

use Crypt::Cipher;
use base 'Crypt::Mode';

sub new { my $class = shift; _new(Crypt::Cipher::_trans_cipher_name(shift), @_) }

1;

=pod

=head1 NAME

Crypt::Mode::CTR - Block cipher mode CTR [Counter mode]

=head1 SYNOPSIS

   use Crypt::Mode::CTR;
   my $m = Crypt::Mode::CTR->new('AES');

   #(en|de)crypt at once
   my $ciphertext = $m->encrypt($plaintext, $key, $iv);
   my $plaintext = $m->decrypt($ciphertext, $key, $iv);

   #encrypt more chunks
   $m->start_encrypt($key, $iv);
   my $ciphertext = $m->add('some data');
   $ciphertext .= $m->add('more data');

   #decrypt more chunks
   $m->start_decrypt($key, $iv);
   my $plaintext = $m->add($some_ciphertext);
   $plaintext .= $m->add($more_ciphertext);

=head1 DESCRIPTION

This module implements CTR cipher mode. B<NOTE:> it works only with ciphers from L<CryptX> (Crypt::Cipher::NNNN).

=head1 METHODS

=head2 new

 my $m = Crypt::Mode::CTR->new($cipher_name);
 #or
 my $m = Crypt::Mode::CTR->new($cipher_name, $ctr_mode, $ctr_width);
 #or
 my $m = Crypt::Mode::CTR->new($cipher_name, $ctr_mode, $ctr_width, $cipher_rounds);

 # $ctr_mode .... 0 little-endian counter (DEFAULT)
 #                1 big-endian counter
 #                2 little-endian + RFC3686 incrementing
 #                3 big-endian + RFC3686 incrementing
 # $ctr_width ... counter width in bytes (DEFAULT = full block width)
 # $cipher_rounds ... optional num of rounds for given cipher

=head2 encrypt

   my $ciphertext = $m->encrypt($plaintext, $key, $iv);

=head2 decrypt

   my $plaintext = $m->decrypt($ciphertext, $key, $iv);

=head2 start_encrypt

See example below L</finish>.

=head2 start_decrypt

See example below L</finish>.

=head2 add

See example below L</finish>.

=head2 finish

   #encrypt more chunks
   $m->start_encrypt($key, $iv);
   my $ciphertext = '';
   $ciphertext .= $m->add('some data');
   $ciphertext .= $m->add('more data');

   #decrypt more chunks
   $m->start_decrypt($key, $iv);
   my $plaintext = '';
   $plaintext .= $m->add($some_ciphertext);
   $plaintext .= $m->add($more_ciphertext);

=head1 SEE ALSO

=over

=item * L<CryptX|CryptX>, L<Crypt::Cipher|Crypt::Cipher>

=item * L<Crypt::Cipher::AES|Crypt::Cipher::AES>, L<Crypt::Cipher::Blowfish|Crypt::Cipher::Blowfish>, ...

=item * L<https://en.wikipedia.org/wiki/Block_cipher_mode_of_operation#Counter_.28CTR.29|https://en.wikipedia.org/wiki/Block_cipher_mode_of_operation#Counter_.28CTR.29>

=back
