NAME
    Apache::AuthenCache - Authentication caching used in conjuction
    with a primary authentication module (Apache::AuthenDBI, etc.)

SYNOPSIS
     # In your httpd.conf
     PerlModule Apache::AuthenCache

     # In httpd.conf or .htaccess:
     AuthName Name
     AuthType Basic
     PerlAuthenHandler Apache::AuthenCache <Primary Authentication Module> Apache::AuthenCache::manage_cache
     <Limit GET>
     require valid-user # Limited to valid-user or user
     </Limit>

     # Optional parameters
     PerlSetVar AuthenCache_cache_size     100 # Maximum number of entries in cache (no default)
     PerlSetVar AuthenCache_cache_time      900 # Number of seconds cache is good for (no default)
     PerlSetVar AuthenCache_nopasswd       on  # Allows authentication with out a password (defaults to off)
     PerlSetVar AuthenCache_encrypted      off # Uses plaintext passwords (defaults to on)
     PerlSetVar AuthenCache_casesensitive  off # Allows for Windows-like case-insensitivity (defaults to on)

DESCRIPTION
    This module implements a caching mechanism in order to speed up
    authentication and to reduce the usage of system resources. It
    must be used in conjunction with a regular mod_perl
    authentication module. (It was designed with AuthenDBI in mind.)
    For mod_perl authentication modules see:

     http://www.perl.com/CPAN-local/modules/by-module/Apache/apache-modlist.html

    When an access controlled request is received
    AuthenCache::handler looks up the username in the cache and
    compares the cached password to the sent password. A new cache
    is created for the first request or if the cache has expired. If
    the passwords match the remaing Authen handlers are removed from
    the stack and OK is returned. If the passwords don't match
    DECLINED is returned and the next Authen handler is called.

    After the primary authentication handler authenticates the user,
    AuthenCache::manage_cache adds the new user to the cache and
    removes the oldest user if AuthenCache_cache_size is set and the
    size of the cache is greater than AuthenCache_cache_size.

PREREQUISITES
    mod_perl 1.11_01 is required. The following call-back hooks need
    to be enabled when making mod_perl:

      perl Makefile.PL PERL_AUTHEN=1 PERL_STACKED_HANDLERS=1 PERL_GET_SET_HANDLERS

    Tie::IxHash is also required.

TODO
    * Make cache LRU
SEE ALSO
    the Apache manpage, the mod_perl manpage

AUTHOR
    Jason Bodnar <jcbodnar@mail.utexas.edu>

COPYRIGHT
    Copyright (C) 1998, Jason Bodnar

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