Authen::Passphrase::LANManagerHalf(3pm) User Contributed Perl Documentation Authen::Passphrase::LANManagerHalf(3pm)
NAME
Authen::Passphrase::LANManagerHalf - passphrases using half the LAN Manager algorithm
SYNOPSIS
use Authen::Passphrase::LANManagerHalf;
$ppr = Authen::Passphrase::LANManagerHalf->new(
hash_hex => "855c3697d9979e78");
$ppr = Authen::Passphrase::LANManagerHalf->new(
passphrase => "passphr");
$ppr = Authen::Passphrase::LANManagerHalf->from_crypt(
'$LM$855c3697d9979e78');
$ppr = Authen::Passphrase::LANManagerHalf->from_rfc2307(
'{CRYPT}$LM$855c3697d9979e78');
$hash = $ppr->hash;
$hash_hex = $ppr->hash_hex;
if($ppr->match($passphrase)) { ...
$passwd = $ppr->as_crypt;
$userPassword = $ppr->as_rfc2307;
DESCRIPTION
An object of this class encapsulates half of a passphrase hashed using the Microsoft LAN Manager hash function. This is a subclass of
Authen::Passphrase, and this document assumes that the reader is familiar with the documentation for that class. For the complete LAN
Manager hash function, see Authen::Passphrase::LANManager.
In a spectacularly bad design decision, the Microsoft LAN Manager hash function splits the passphrase into two parts and hashes them
separately. It is therefore possible to separate the halves of a LAN Manager hash, and do things with them (such as crack them)
separately. This class is about using such a hash half on its own.
The half hash algorithm can be used on up to seven Latin-1 characters of passphrase. First the passphrase is folded to uppercase, and
zero-padded to seven bytes. Then the seven bytes are used as a 56-bit DES key, to encrypt the fixed plaintext block "KGS!@#$%". The eight
byte ciphertext block is the half hash. There is no salt.
Warning: Don't even think about using this seriously. It's an exceptionally weak design, flawed in pretty much every respect.
CONSTRUCTORS
Authen::Passphrase::LANManagerHalf->new(ATTR => VALUE, ...)
Generates a new passphrase recogniser object using the LAN Manager half hash algorithm. The following attributes may be given:
hash
The hash, as a string of 8 bytes.
hash_hex
The hash, as a string of 16 hexadecimal digits.
passphrase
A passphrase that will be accepted.
Either the hash or the passphrase must be given.
Authen::Passphrase::LANManagerHalf->from_crypt(PASSWD)
Generates a new LAN Manager half passphrase recogniser object from a crypt string. The crypt string must consist of "$LM$" followed by
the hash in lowercase hexadecimal.
Authen::Passphrase::LANManagerHalf->from_rfc2307(USERPASSWORD)
Generates a new LAN Manager half passphrase recogniser object from an RFC 2307 string. The string must consist of "{CRYPT}" (case
insensitive) followed by an acceptable crypt string.
METHODS
$ppr->hash
Returns the hash value, as a string of 8 bytes.
$ppr->hash_hex
Returns the hash value, as a string of 16 hexadecimal digits.
$ppr->match(PASSPHRASE)
$ppr->as_crypt
$ppr->as_rfc2307
These methods are part of the standard Authen::Passphrase interface.
SEE ALSO
Authen::Passphrase, Authen::Passphrase::LANManager, Crypt::DES
AUTHOR
Andrew Main (Zefram) <zefram@fysh.org>
COPYRIGHT
Copyright (C) 2006, 2007, 2009, 2010, 2012 Andrew Main (Zefram) <zefram@fysh.org>
LICENSE
This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
perl v5.14.2 2012-02-07 Authen::Passphrase::LANManagerHalf(3pm)