Crypt::AuthEnc::GCM(3) | User Contributed Perl Documentation | Crypt::AuthEnc::GCM(3) |
NAME
Crypt::AuthEnc::GCM - Authenticated encryption in GCM mode
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, $tag);
DESCRIPTION
Galois/Counter Mode (GCM) - provides encryption and authentication.
EXPORT
Nothing is exported by default.
You can export selected functions:
use Crypt::AuthEnc::GCM qw(gcm_encrypt_authenticate gcm_decrypt_verify);
FUNCTIONS
gcm_encrypt_authenticate
my ($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
gcm_decrypt_verify
my $plaintext = gcm_decrypt_verify($cipher, $key, $iv, $adata, $ciphertext, $tag); # on error returns undef
METHODS
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)
iv_add
Set initialization vector (IV).
$ae->iv_add($iv_data); #can be called multiple times
adata_add
Add additional authenticated data. Can be called after all "iv_add" calls but 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)
reset
$ae->reset;
clone
my $ae_new = $ae->clone;
SEE ALSO
- CryptX, Crypt::AuthEnc::CCM, Crypt::AuthEnc::EAX, Crypt::AuthEnc::OCB
- https://en.wikipedia.org/wiki/Galois/Counter_Mode
2024-10-20 | perl v5.40.0 |