The Perl Toolchain Summit needs more sponsors. If your company depends on Perl, please support this very important event.

NAME

Crypt::AuthEnc::GCM - Authenticated encryption in GCM mode

SYNOPSIS

 ### OO interface

 # encrypt and authenticate
 my $ae = Crypt::AuthEnc::GCM->new("AES", $key);
 $ae->iv_add('data_iv1');
 $ae->iv_add('data_iv2');
 $ae->aad_add('data_aad1');
 $ae->aad_add('data_aad2');
 $ct = $ae->encrypt_add('data1');
 $ct = $ae->encrypt_add('data2');
 $ct = $ae->encrypt_add('data3');
 $tag = $ae->encrypt_done();

 # decrypt and verify
 my $ae = Crypt::AuthEnc::GCM->new("AES", $key);
 $ae->iv_add('data_iv1');
 $ae->iv_add('data_iv2');
 $ae->aad_add('data_aad1');
 $ae->aad_add('data_aad2');
 $pt = $ae->decrypt_add($ciphertext1);
 $pt = $ae->decrypt_add($ciphertext2);
 $pt = $ae->decrypt_add($ciphertext3);
 $tag = $ae->decrypt_done();

 ### 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 ...... initial vector
 # $adata ... additional authentication 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);

 # $cipher .. 'AES' or name of any other cipher
 # $key ..... encryption key of proper length

iv_add

 $ae->iv_add($iv_data);                 #can be called multiple times

aad_add

Can be called after all iv_add calls but before the first encrypt_add or decrypt_add;

 $ae->aad_add($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();

decrypt_add

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

decrypt_done

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

reset

 $ae->reset;

clone

 my $ae_new = $ae->clone;

SEE ALSO