137 lines
3.9 KiB
Perl
137 lines
3.9 KiB
Perl
package Crypt::AuthEnc::CCM;
|
|
|
|
use strict;
|
|
use warnings;
|
|
our $VERSION = '0.058_002';
|
|
|
|
require Exporter; our @ISA = qw(Exporter); ### use Exporter 'import';
|
|
our %EXPORT_TAGS = ( all => [qw( ccm_encrypt_authenticate ccm_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::CCM - Authenticated encryption in CCM mode
|
|
|
|
=head1 SYNOPSIS
|
|
|
|
### OO interface
|
|
use Crypt::AuthEnc::CCM;
|
|
|
|
# encrypt and authenticate
|
|
my $ae = Crypt::AuthEnc::CCM->new("AES", $key, $iv, $adata, $tag_len, $pt_len);
|
|
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::CCM->new("AES", $key, $iv, $adata, $tag_len, $pt_len);
|
|
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::CCM qw(ccm_encrypt_authenticate ccm_decrypt_verify);
|
|
|
|
($ciphertext, $tag) = ccm_encrypt_authenticate('AES', $key, $nonce, $adata, $tag_len, $plaintext);
|
|
$plaintext = ccm_decrypt_verify('AES', $key, $nonce, $adata, $ciphertext, $tag);
|
|
|
|
=head1 DESCRIPTION
|
|
|
|
CCM is a encrypt+authenticate mode that is centered around using AES (or any 16-byte cipher) as a primitive.
|
|
Unlike EAX and OCB mode, it is only meant for packet mode where the length of the input is known in advance.
|
|
|
|
=head1 EXPORT
|
|
|
|
Nothing is exported by default.
|
|
|
|
You can export selected functions:
|
|
|
|
use Crypt::AuthEnc::CCM qw(ccm_encrypt_authenticate ccm_decrypt_verify);
|
|
|
|
=head1 FUNCTIONS
|
|
|
|
=head2 ccm_encrypt_authenticate
|
|
|
|
my ($ciphertext, $tag) = ccm_encrypt_authenticate($cipher, $key, $nonce, $adata, $tag_len, $plaintext);
|
|
|
|
# $cipher .. 'AES' or name of any other cipher with 16-byte block len
|
|
# $key ..... key of proper length (e.g. 128/192/256bits for AES)
|
|
# $nonce ... unique nonce/salt (no need to keep it secret)
|
|
# $adata ... additional authenticated data
|
|
# $tag_len . required length of output tag
|
|
|
|
CCM parameters should follow L<http://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-38c.pdf>
|
|
|
|
# tag length: 4, 6, 8, 10, 12, 14, 16 (reasonable minimum is 8)
|
|
# nonce length: 7, 8, 9, 10, 11, 12, 13 (if you are not sure, use 11)
|
|
# BEWARE nonce length determines max. enc/dec data size: max_data_size = 2^(8*(15-nonce_len))
|
|
|
|
=head2 ccm_decrypt_verify
|
|
|
|
my $plaintext = ccm_decrypt_verify($cipher, $key, $nonce, $adata, $ciphertext, $tag);
|
|
# on error returns undef
|
|
|
|
=head1 METHODS
|
|
|
|
=head2 new
|
|
|
|
my $ae = Crypt::AuthEnc::CCM->new($cipher, $key, $nonce, $adata, $tag_len, $pt_len);
|
|
|
|
# $cipher .. 'AES' or name of any other cipher with 16-byte block len
|
|
# $key ..... key of proper length (e.g. 128/192/256bits for AES)
|
|
# $nonce ... unique nonce/salt (no need to keep it secret)
|
|
# $adata ... additional authenticated data
|
|
# $tag_len . required length of output tag
|
|
# $pt_len .. expected length of plaintext/ciphertext to encrypt/decrypt
|
|
|
|
=head2 encrypt_add
|
|
|
|
$ciphertext = $ae->encrypt_add($data); # can be called multiple times
|
|
|
|
=head2 encrypt_done
|
|
|
|
my $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 clone
|
|
|
|
my $ae_new = $ae->clone;
|
|
|
|
=head1 SEE ALSO
|
|
|
|
=over
|
|
|
|
=item * L<CryptX|CryptX>, L<Crypt::AuthEnc::EAX|Crypt::AuthEnc::EAX>, L<Crypt::AuthEnc::GCM|Crypt::AuthEnc::GCM>, L<Crypt::AuthEnc::OCB|Crypt::AuthEnc::OCB>
|
|
|
|
=item * L<https://en.wikipedia.org/wiki/CCM_mode|https://en.wikipedia.org/wiki/CCM_mode>
|
|
|
|
=back
|
|
|
|
=cut
|