NAME

File::KDBX::Cipher - A block cipher mode or cipher stream

VERSION

version 0.906

SYNOPSIS

use File::KDBX::Cipher;

my $cipher = File::KDBX::Cipher->new(uuid => $uuid, key => $key, iv => $iv);

my $ciphertext = $cipher->encrypt('plaintext');
$ciphertext .= $cipher->encrypt('more plaintext');
$ciphertext .= $cipher->finish;

my $plaintext = $cipher->decrypt('ciphertext');
$plaintext .= $cipher->decrypt('more ciphertext');
$plaintext .= $cipher->finish;

DESCRIPTION

A cipher is used to encrypt and decrypt KDBX files. The File::KDBX distribution comes with several pre-registered ciphers ready to go:

  • 61AB05A1-9464-41C3-8D74-3A563DF8DD35 - AES128 (legacy)

  • 31C1F2E6-BF71-4350-BE58-05216AFC5AFF - AES256

  • D6038A2B-8B6F-4CB5-A524-339A31DBB59A - ChaCha20

  • 716E1C8A-EE17-4BDC-93AE-A977B882833A - Salsa20

  • 098563FF-DDF7-4F98-8619-8079F6DB897A - Serpent

  • AD68F29F-576F-4BB9-A36A-D47AF965346C - Twofish

NOTE: If you want your KDBX file to be readable by other KeePass implementations, you must use a UUID and algorithm that they support. From the list above, AES256 and ChaCha20 are well-supported. You should avoid AES128 for new databases.

You can also "register" your own cipher. Here is a skeleton:

package File::KDBX::Cipher::MyCipher;

use parent 'File::KDBX::Cipher';

File::KDBX::Cipher->register(
    # $uuid, $package, %args
    "\x12\x34\x56\x78\x9a\xbc\xde\xfg\x12\x34\x56\x78\x9a\xbc\xde\xfg" => __PACKAGE__,
);

sub init { ... } # optional

sub encrypt { ... }
sub decrypt { ... }
sub finish  { ... }

sub key_size   { ... }
sub iv_size    { ... }
sub block_size { ... }

ATTRIBUTES

uuid

$uuid = $cipher->uuid;

Get the UUID if the cipher was constructed with one.

stream_id

$stream_id = $cipher->stream_id;

Get the stream ID if the cipher was constructed with one.

key

$key = $cipher->key;

Get the raw encryption key.

iv

$iv = $cipher->iv;

Get the initialization vector.

iv_size

$size = $cipher->iv_size;

Get the expected size of the initialization vector, in bytes.

key_size

$size = $cipher->key_size;

Get the size the mode or stream expects the key to be, in bytes.

block_size

$size = $cipher->block_size;

Get the block size, in bytes.

algorithm

Get the symmetric cipher algorithm.

METHODS

new

new_from_uuid

new_from_stream_id

$cipher = File::KDBX::Cipher->new(uuid => $uuid, key => $key, iv => $iv);
# OR
$cipher = File::KDBX::Cipher->new_from_uuid($uuid, key => $key, iv => $iv);

$cipher = File::KDBX::Cipher->new(stream_id => $id, key => $key);
# OR
$cipher = File::KDBX::Cipher->new_from_stream_id($id, key => $key);

Construct a new File::KDBX::Cipher.

This is a factory method which returns a subclass.

init

$self->init;

Called by "new" to set attributes. You normally shouldn't call this. Returns itself to allow method chaining.

encrypt

$ciphertext = $cipher->encrypt($plaintext, ...);

Encrypt some data.

decrypt

$plaintext = $cipher->decrypt($ciphertext, ...);

Decrypt some data.

finish

$ciphertext .= $cipher->finish; # if encrypting
$plaintext  .= $cipher->finish; # if decrypting

Finish the stream.

encrypt_finish

$ciphertext = $cipher->encrypt_finish($plaintext, ...);

Encrypt and finish a stream in one call.

decrypt_finish

$plaintext = $cipher->decrypt_finish($ciphertext, ...);

Decrypt and finish a stream in one call.

register

File::KDBX::Cipher->register($uuid => $package, %args);

Register a cipher. Registered ciphers can be used to encrypt and decrypt KDBX databases. A cipher's UUID must be unique and musn't change. A cipher UUID is written into each KDBX file and the associated cipher must be registered with the same UUID in order to decrypt the KDBX file.

$package should be a Perl package relative to File::KDBX::Cipher:: or prefixed with a + if it is a fully-qualified package. %args are passed as-is to the cipher's "init" method.

unregister

File::KDBX::Cipher->unregister($uuid);

Unregister a cipher. Unregistered ciphers can no longer be used to encrypt and decrypt KDBX databases, until reregistered (see "register").

BUGS

Please report any bugs or feature requests on the bugtracker website https://github.com/chazmcgarvey/File-KDBX/issues

When submitting a bug or request, please include a test-file or a patch to an existing test-file that illustrates the bug or desired feature.

AUTHOR

Charles McGarvey <ccm@cpan.org>

COPYRIGHT AND LICENSE

This software is copyright (c) 2022 by Charles McGarvey.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.