NAME

    Crypt::Simple - encrypt stuff simply

SYNOPSIS

      use Crypt::Simple;
  
      my $data = encrypt(@stuff);

      my @same_stuff = decrypt($data);

DESCRIPTION

    Maybe you have a web application and you need to store some session data at
    the client side (in a cookie or hidden form fields) but you don't want the
    user to be able to mess with the data. Maybe you want to save secret
    information to a text file. Maybe you have better ideas of what to do with
    encrypted stuff!

    This little module will convert all your data into nice base64 text that you
    can save in a text file, send in an email, store in a cookie or web page, or
    bounce around the Net. The data you encrypt can be as simple or as
    complicated as you like.

KEY

    If you don't pass any options when using "Crypt::Simple" we will generate a
    key for you based on the name of your module that uses this one. In many
    cases this works fine, but you may want more control over the key.

INTERNALS

    "Crypt::Simple" is really just a wrapper round a few other useful Perl
    modules: you may want to read the documentation for these modules too.

    We use "FreezeThaw" to squish all your data into a concise textual
    representation. We use "Compress::Zlib" to compress this string, and then
    use "Crypt::Blowfish" in a home-brew CBC mode to perform the encryption.
    Somewhere in this process we also add a MD5 digest (using "Digest::MD5").
    Then we throw the whole thing through "MIME::Base64" to produce a nice bit
    of text for you to play with.

    Decryption, obviously, is the reverse of this process.

WARNING

    Governments throughout the world do not like encryption because it makes it
    difficult for them to look at all your stuff. Each country has a different
    policy designed to stop you using encryption: some governments are honest
    enough to make it illegal; some think it is a dangerous weapon; some insist
    that you are free to encrypt, but only evil people would want to; some make
    confusing and contradictory laws because they try to do all of the above.

    Although this modules itself does not include any encryption code, it does
    use another module that contains encryption code, and this documentation
    mentions encryption. Downloading, using, or reading this modules could be
    illegal where you live.

AUTHOR

    Marty Pauley <marty@kasei.com>

COPYRIGHT

      Copyright (C) 2001 Kasei Limited

      This program is free software; you can redistribute it and/or modify it under
      the terms of the GNU General Public License; either version 2 of the License,
      or (at your option) any later version.

      This program is distributed in the hope that it will be useful, but WITHOUT
      ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
      FOR A PARTICULAR PURPOSE.

