NAME

       Authen::Passphrase::MySQL41 - passphrases using the MySQL v4.1 algorithm

SYNOPSIS

               use Authen::Passphrase::MySQL41;

               $ppr = Authen::Passphrase::MySQL41->new(
                       hash_hex => "9CD12C48C4C5DD62914B".
                                   "3FABB93131746E9E9115");

               $ppr = Authen::Passphrase::MySQL41->new(
                       passphrase => "passphrase");

               $hash = $ppr->hash;
               $hash_hex = $ppr->hash_hex;

               if($ppr->match($passphrase)) { ...

DESCRIPTION

       An object of this class encapsulates a passphrase hashed using the algorithm used by MySQL
       from version 4.1.  This is a subclass of Authen::Passphrase, and this document assumes
       that the reader is familiar with the documentation for that class.

       The MySQL v4.1 hash scheme is based on the SHA-1 digest algorithm.  The passphrase is
       first hashed using SHA-1, then the output of that stage is hashed using SHA-1 again.  The
       final hash is the output of the second SHA-1.  No salt is used.

       In MySQL the hash is represented as a "*" followed by 40 uppercase hexadecimal digits.

       The lack of salt is a weakness in this scheme.  Salted SHA-1 is a better scheme; see
       Authen::Passphrase::SaltedDigest.

CONSTRUCTOR

       Authen::Passphrase::MySQL41->new(ATTR => VALUE, ...)
           Generates a new passphrase recogniser object using the MySQL v4.1 algorithm.  The
           following attributes may be given:

           hash
               The hash, as a string of 20 bytes.

           hash_hex
               The hash, as a string of 40 hexadecimal digits.

           passphrase
               A passphrase that will be accepted.

           Either the hash or the passphrase must be given.

METHODS

       $ppr->hash
           Returns the hash value, as a string of 20 bytes.

       $ppr->hash_hex
           Returns the hash value, as a string of 40 uppercase hexadecimal digits.

       $ppr->match(PASSPHRASE)
           This method is part of the standard Authen::Passphrase interface.

SEE ALSO

       Authen::Passphrase, Digest::SHA

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.