libcryptx-perl/lib/Crypt/AuthEnc/ChaCha20Poly1305.pm
2018-03-22 15:54:03 +01:00

148 lines
4.1 KiB
Perl

package Crypt::AuthEnc::ChaCha20Poly1305;
use strict;
use warnings;
our $VERSION = '0.058_002';
require Exporter; our @ISA = qw(Exporter); ### use Exporter 'import';
our %EXPORT_TAGS = ( all => [qw( chacha20poly1305_encrypt_authenticate chacha20poly1305_decrypt_verify )] );
our @EXPORT_OK = ( @{ $EXPORT_TAGS{'all'} } );
our @EXPORT = qw();
use Carp;
$Carp::Internal{(__PACKAGE__)}++;
use CryptX;
sub CLONE_SKIP { 1 } # prevent cloning
1;
=pod
=head1 NAME
Crypt::AuthEnc::ChaCha20Poly1305 - Authenticated encryption in ChaCha20-Poly1305 mode
=head1 SYNOPSIS
### OO interface
use Crypt::AuthEnc::ChaCha20Poly1305;
# encrypt and authenticate
my $ae = Crypt::AuthEnc::ChaCha20Poly1305->new($key, $iv);
$ae->adata_add('additional_authenticated_data1');
$ae->adata_add('additional_authenticated_data2');
my $ct = $ae->encrypt_add('data1');
$ct .= $ae->encrypt_add('data2');
$ct .= $ae->encrypt_add('data3');
my $tag = $ae->encrypt_done();
# decrypt and verify
my $ae = Crypt::AuthEnc::ChaCha20Poly1305->new($key, $iv);
$ae->adata_add('additional_authenticated_data1');
$ae->adata_add('additional_authenticated_data2');
my $pt = $ae->decrypt_add('ciphertext1');
$pt .= $ae->decrypt_add('ciphertext2');
$pt .= $ae->decrypt_add('ciphertext3');
my $tag = $ae->decrypt_done();
die "decrypt failed" unless $tag eq $expected_tag;
#or
my $result = $ae->decrypt_done($expected_tag); # 0 or 1
### functional interface
use Crypt::AuthEnc::ChaCha20Poly1305 qw(chacha20poly1305_encrypt_authenticate chacha20poly1305_decrypt_verify);
my ($ciphertext, $tag) = chacha20poly1305_encrypt_authenticate($key, $iv, $adata, $plaintext);
my $plaintext = chacha20poly1305_decrypt_verify($key, $iv, $adata, $ciphertext, $tag);
=head1 DESCRIPTION
Provides encryption and authentication based on ChaCha20 + Poly1305 as defined in RFC 7539 - L<https://tools.ietf.org/html/rfc7539>
=head1 EXPORT
Nothing is exported by default.
You can export selected functions:
use Crypt::AuthEnc::ChaCha20Poly1305 qw(chacha20poly1305_encrypt_authenticate chacha20poly1305_decrypt_verify);
=head1 FUNCTIONS
=head2 chacha20poly1305_encrypt_authenticate
my ($ciphertext, $tag) = chacha20poly1305_encrypt_authenticate($key, $iv, $adata, $plaintext);
# $key ..... key of proper length (128 or 256 bits / 16 or 32 bytes)
# $iv ...... initialization vector (64 or 96 bits / 8 or 12 bytes)
# $adata ... additional authenticated data (optional)
=head2 chacha20poly1305_decrypt_verify
my $plaintext = chacha20poly1305_decrypt_verify($key, $iv, $adata, $ciphertext, $tag);
# on error returns undef
=head1 METHODS
=head2 new
my $ae = Crypt::AuthEnc::ChaCha20Poly1305->new($key, $iv);
# $key ..... encryption key of proper length (128 or 256 bits / 16 or 32 bytes)
# $iv ...... initialization vector (64 or 96 bits / 8 or 12 bytes)
=head2 adata_add
Add B<additional authenticated data>.
Can be called before the first C<encrypt_add> or C<decrypt_add>;
$ae->adata_add($aad_data); # can be called multiple times
=head2 encrypt_add
$ciphertext = $ae->encrypt_add($data); # can be called multiple times
=head2 encrypt_done
$tag = $ae->encrypt_done(); # returns $tag value
=head2 decrypt_add
$plaintext = $ae->decrypt_add($ciphertext); # can be called multiple times
=head2 decrypt_done
my $tag = $ae->decrypt_done; # returns $tag value
#or
my $result = $ae->decrypt_done($tag); # returns 1 (success) or 0 (failure)
=head2 set_iv
my $ae = Crypt::AuthEnc::ChaCha20Poly1305->new($key)->set_iv($iv);
# $iv ...... initialization vector (64 or 96 bits / 8 or 12 bytes)
=head2 set_iv_rfc7905
See L<https://tools.ietf.org/html/rfc7905>
my $ae = Crypt::AuthEnc::ChaCha20Poly1305->new($key)->set_iv_rfc7905($iv, $seqnum);
# $iv ...... initialization vector (96 bits / 12 bytes)
# $seqnum .. 64bit integer (sequence number)
=head2 clone
my $ae_new = $ae->clone;
=head1 SEE ALSO
=over
=item * L<CryptX|CryptX>, L<Crypt::AuthEnc::GCM|Crypt::AuthEnc::GCM>, L<Crypt::AuthEnc::CCM|Crypt::AuthEnc::CCM>, L<Crypt::AuthEnc::EAX|Crypt::AuthEnc::EAX>, L<Crypt::AuthEnc::OCB|Crypt::AuthEnc::OCB>
=item * L<https://tools.ietf.org/html/rfc7539>
=back
=cut