Crypt::AuthEnc::EAX(3) | User Contributed Perl Documentation | Crypt::AuthEnc::EAX(3) |
NAME
Crypt::AuthEnc::EAX - Authenticated encryption in EAX mode
SYNOPSIS
### OO interface use Crypt::AuthEnc::EAX; # encrypt and authenticate my $ae = Crypt::AuthEnc::EAX->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::EAX->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::EAX qw(eax_encrypt_authenticate eax_decrypt_verify); my ($ciphertext, $tag) = eax_encrypt_authenticate('AES', $key, $iv, $adata, $plaintext); my $plaintext = eax_decrypt_verify('AES', $key, $iv, $adata, $ciphertext, $tag);
DESCRIPTION
EAX is a mode that requires a cipher, CTR and OMAC support and provides encryption and authentication. It is initialized with a random IV that can be shared publicly, additional authenticated data which can be fixed and public, and a random secret symmetric key.
EXPORT
Nothing is exported by default.
You can export selected functions:
use Crypt::AuthEnc::EAX qw(eax_encrypt_authenticate eax_decrypt_verify);
FUNCTIONS
eax_encrypt_authenticate
my ($ciphertext, $tag) = eax_encrypt_authenticate($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 ...... unique initialization vector (no need to keep it secret) # $adata ... additional authenticated data
eax_decrypt_verify
my $plaintext = eax_decrypt_verify($cipher, $key, $iv, $adata, $ciphertext, $tag); # on error returns undef
METHODS
new
my $ae = Crypt::AuthEnc::EAX->new($cipher, $key, $iv); #or my $ae = Crypt::AuthEnc::EAX->new($cipher, $key, $iv, $adata); # $cipher .. 'AES' or name of any other cipher with 16-byte block len # $key ..... AES key of proper length (128/192/256bits) # $iv ...... unique initialization vector (no need to keep it secret) # $adata ... additional authenticated data (optional)
adata_add
$ae->adata_add($adata); # 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)
clone
my $ae_new = $ae->clone;
SEE ALSO
- CryptX, Crypt::AuthEnc::CCM, Crypt::AuthEnc::GCM, Crypt::AuthEnc::OCB
- https://en.wikipedia.org/wiki/EAX_mode
2024-10-20 | perl v5.40.0 |