149 lines
3.7 KiB
Perl
149 lines
3.7 KiB
Perl
package Crypt::AuthEnc::GCM;
|
|
|
|
use strict;
|
|
use warnings;
|
|
our $VERSION = '0.058_002';
|
|
|
|
require Exporter; our @ISA = qw(Exporter); ### use Exporter 'import';
|
|
our %EXPORT_TAGS = ( all => [qw( gcm_encrypt_authenticate gcm_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::GCM - Authenticated encryption in GCM mode
|
|
|
|
=head1 SYNOPSIS
|
|
|
|
### OO interface
|
|
use Crypt::AuthEnc::GCM;
|
|
|
|
# encrypt and authenticate
|
|
my $ae = Crypt::AuthEnc::GCM->new("AES", $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::GCM->new("AES", $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::GCM qw(gcm_encrypt_authenticate gcm_decrypt_verify);
|
|
|
|
my ($ciphertext, $tag) = gcm_encrypt_authenticate('AES', $key, $iv, $adata, $plaintext);
|
|
my $plaintext = gcm_decrypt_verify('AES', $key, $iv, $adata, $ciphertext, $tag);
|
|
|
|
=head1 DESCRIPTION
|
|
|
|
Galois/Counter Mode (GCM) - provides encryption and authentication.
|
|
|
|
=head1 EXPORT
|
|
|
|
Nothing is exported by default.
|
|
|
|
You can export selected functions:
|
|
|
|
use Crypt::AuthEnc::GCM qw(gcm_encrypt_authenticate gcm_decrypt_verify);
|
|
|
|
=head1 FUNCTIONS
|
|
|
|
=head2 gcm_encrypt_authenticate
|
|
|
|
my ($ciphertext, $tag) = gcm_encrypt_authenticate($cipher, $key, $iv, $adata, $plaintext);
|
|
|
|
# $cipher .. 'AES' or name of any other cipher with 16-byte block len
|
|
# $key ..... AES key of proper length (128/192/256bits)
|
|
# $iv ...... initialization vector
|
|
# $adata ... additional authenticated data
|
|
|
|
=head2 gcm_decrypt_verify
|
|
|
|
my $plaintext = gcm_decrypt_verify($cipher, $key, $iv, $adata, $ciphertext, $tag);
|
|
# on error returns undef
|
|
|
|
=head1 METHODS
|
|
|
|
=head2 new
|
|
|
|
my $ae = Crypt::AuthEnc::GCM->new($cipher, $key);
|
|
#or
|
|
my $ae = Crypt::AuthEnc::GCM->new($cipher, $key, $iv);
|
|
|
|
# $cipher .. 'AES' or name of any other cipher
|
|
# $key ..... encryption key of proper length
|
|
# $iv ...... initialization vector (optional, you can set it later via iv_add method)
|
|
|
|
=head2 iv_add
|
|
|
|
Set initialization vector (IV).
|
|
|
|
$ae->iv_add($iv_data); #can be called multiple times
|
|
|
|
=head2 adata_add
|
|
|
|
Add B<additional authenticated data>.
|
|
Can be called B<after> all C<iv_add> calls but 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 reset
|
|
|
|
$ae->reset;
|
|
|
|
=head2 clone
|
|
|
|
my $ae_new = $ae->clone;
|
|
|
|
=head1 SEE ALSO
|
|
|
|
=over
|
|
|
|
=item * L<CryptX|CryptX>, L<Crypt::AuthEnc::CCM|Crypt::AuthEnc::CCM>, L<Crypt::AuthEnc::EAX|Crypt::AuthEnc::EAX>, L<Crypt::AuthEnc::OCB|Crypt::AuthEnc::OCB>
|
|
|
|
=item * L<https://en.wikipedia.org/wiki/Galois/Counter_Mode>
|
|
|
|
=back
|
|
|
|
=cut
|