Crypt::AuthEnc::ChaCha20Poly1305 - Authenticated encryption in ChaCha20-Poly1305 mode

NAME  SYNOPSIS  DESCRIPTION  EXPORT  FUNCTIONS  chacha20poly1305_encrypt_authenticate  chacha20poly1305_decrypt_verify  METHODS  new  adata_add  encrypt_add  encrypt_done  decrypt_add  decrypt_done  set_iv  set_iv_rfc7905  clone  SEE ALSO 

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NAME

Crypt::AuthEnc::ChaCha20Poly1305 − Authenticated encryption in ChaCha20−Poly1305 mode

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);

DESCRIPTION

Provides encryption and authentication based on ChaCha20 + Poly1305 as defined in RFC 7539 − <https://tools.ietf.org/html/rfc7539>

EXPORT

Nothing is exported by default.

You can export selected functions:

use Crypt::AuthEnc::ChaCha20Poly1305 qw(chacha20poly1305_encrypt_authenticate chacha20poly1305_decrypt_verify);

FUNCTIONS

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)

chacha20poly1305_decrypt_verify

my $plaintext = chacha20poly1305_decrypt_verify($key, $iv, $adata, $ciphertext, $tag);
# on error returns undef

METHODS

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)

adata_add

Add additional authenticated data. Can be called before the first "encrypt_add" or "decrypt_add";

$ae−>adata_add($aad_data); # can be called multiple times

encrypt_add

$ciphertext = $ae−>encrypt_add($data); # can be called multiple times

encrypt_done

$tag = $ae−>encrypt_done(); # returns $tag value

decrypt_add

$plaintext = $ae−>decrypt_add($ciphertext); # can be called multiple times

decrypt_done

my $tag = $ae−>decrypt_done; # returns $tag value
#or
my $result = $ae−>decrypt_done($tag); # returns 1 (success) or 0 (failure)

set_iv

my $ae = Crypt::AuthEnc::ChaCha20Poly1305−>new($key)−>set_iv($iv);
# $iv ...... initialization vector (64 or 96 bits / 8 or 12 bytes)

set_iv_rfc7905

See <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)

clone

my $ae_new = $ae−>clone;

SEE ALSO

	•		CryptX, Crypt::AuthEnc::GCM, Crypt::AuthEnc::CCM, Crypt::AuthEnc::EAX, Crypt::AuthEnc::OCB
	•		<https://tools.ietf.org/html/rfc7539>

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