Provided by: libcgi-application-plugin-authorization-perl_0.07-2_all bug

NAME

       CGI::Application::Plugin::Authorization - Authorization framework for CGI::Application

SYNOPSIS

        use base qw(CGI::Application);
        use CGI::Application::Plugin::Authentication;
        use CGI::Application::Plugin::Authorization;

        # default config for runmode authorization
        __PACKAGE__->authz->config(
            DRIVER => [ 'HTGroup', FILE => 'htgroup' ],
        );

        # Using a named configuration to distinguish it from
        # the above configuration
        __PACKAGE__->authz('dbaccess')->config(
            DRIVER => [ 'DBI',
                DBH   => $self->dbh,
                TABLES      => ['user', 'access'],
                JOIN_ON     => 'user.id = access.user_id',
                CONSTRAINTS => {
                    'user.name'      => '__USERNAME__',
                    'access.table'   => '__PARAM_1__',
                    'access.item_id' => '__PARAM_2__'
                }
            ],
        );

        sub admin_runmode {
           my $self = shift;

           # User must be in the admin group to have access to this runmode
           return $self->authz->forbidden unless $self->authz->authorize('admin');

           # rest of the runmode
           ...
        }

        sub update_widget {
           my $self = shift;
           my $widget = $self->query->param('widget_id');

           # Can this user edit this widget in the widgets table?
           return $self->authz->forbidden unless $self->authz('dbaccess')->authorize(widgets => $widget);

           # save changes to the widget
           ...
        }

DESCRIPTION

       CGI::Application::Plugin::Authorization adds the ability to authorize users for specific
       tasks.  Once a user has been authenticated and you know who you are dealing with, you can
       then use this plugin to control what that user has access to.  It imports two methods
       ("authz" and "authorization") into your CGI::Application module.  Both of these methods
       are interchangeable, so you should choose one and use it consistently throughout your
       code.  Through the authz method you can call all the methods of the
       CGI::Application::Plugin::Authorization plugin.

   Named Configurations
       There could be multiple ways that you may want to authorize actions in different parts of
       your code.  These differences may conflict with each other.  For example you may have
       runmode level authorization that requires that the user belongs to a certain group.  But
       secondly, you may have row level database authorization that requires that the username
       column of the table contains the name of the current user.  These configurations would
       conflict with each other since they are authorizing using different information.  To solve
       this you can create multiple named configurations, by specifying a unique name to the
       c<authz> method.

        __PACKAGE__->authz('dbaccess')->config(
            DRIVER => [ 'DBI', ... ],
        );
        # later
        $self->authz('dbaccess')->authorize(widgets => $widget_id);

EXPORTED METHODS

   authz -and- authorization
       These methods are interchangeable and provided for users that either prefer brevity, or
       clarity.  Everything is controlled through this method call, which will return a
       CGI::Application::Plugin::Authorization object, or just the class name if called as a
       class method.  When using the plugin, you will always first call $self->authz or
       __PACKAGE__->authz and then the method you wish to invoke.  You can create multiple named
       authorization modules by providing a unique name to the call to authz.  This will allow
       you to handle different types of authorization in your modules.  For example, you could
       use the main configuration to do runmode level authorization, and use a named
       configuration to manage database row level authorization.

METHODS

   config
       This method is used to configure the CGI::Application::Plugin::Authorization module.  It
       can be called as an object method, or as a class method.

       The following parameters are accepted:

       DRIVER
           Here you can choose which authorization module(s) you want to use to perform the
           authorization.  For simplicity, you can leave off the
           CGI::Application::Plugin::Authorization::Driver:: part when specifying the DRIVER
           parameter.  If this module requires extra parameters, you can pass an array reference
           that contains as the first parameter the name of the module, and the required
           parameters as the rest of the array.  You can provide multiple drivers which will be
           used, in order, to check the permissions until a valid response is received.

             DRIVER => [ 'DBI', dbh => $self->dbh ],

             - or -

             DRIVER => [
               [ 'HTGroup', file => '.htgroup' ],
               [ 'LDAP', binddn => '...', host => 'localhost', ... ]
             ],

       FORBIDDEN_RUNMODE
           Here you can specify a runmode that the user will be redirected to if they fail the
           authorization checks.

             FORBIDDEN_RUNMODE => 'forbidden'

       FORBIDDEN_URL
           If your forbidden page is external to this module, then you can use this option to
           specify a URL that the user will be redirected to when they fail the authorization
           checks. If both FORBIDDEN_URL and FORBIDDEN_RUNMODE are specified, then the latter
           will take precedence.

             FORBIDDEN_URL => 'http://example.com/forbidden.html'

       GET_USERNAME
           This option allows you to provide a method that should return us the username of the
           currently logged in user.  It will be passed the current authz objects as the only
           parameter.  This is not a required option, and can be omitted if you use the
           Authentication plugin, or if your authentication system sets $ENV{REMOTE_USER}.

             GET_USERNAME => sub { my $authz = shift; return $authz->cgiapp->my_username }

   authz_runmodes
       This method takes a list of runmodes that are to be authorized, and the authorization
       rules for said runmodes.  If a user tries to access one of these runmodes, then they will
       be redirected to the forbidden page unless authorization is granted.

       The runmode names can be simple strings, regular expressions, coderefs (which are passed
       the name of the runmode as their only parameter), or special directives that start with a
       colon.

       The authorization rules can be simple strings representing the name of the group that the
       user must be a member of, as a list-ref of group names (of which the user only has to be a
       member of any one of the groups, or as a code-ref that will be called (with no
       parameters).

       This method is cumulative, so if it is called multiple times, the new values are appended
       to the list of existing entries.  It returns a list containing all of the entries that
       have been configured thus far.

       NOTE: compatibility with the interface as was defined in 0.06 is preserved.  0.06 allowed
       for runmodes to be passed in as a list-ref of two-element lists to specify authorization
       rules.  Although this interface is supported, the extra list-refs aren't necessary.

       :all - All runmodes in this module will require authorization

         # match all runmodes
         __PACKAGE__->authz->authz_runmodes(
             ':all' => 'admin',
             );

         # only protect runmodes one and two
         __PACKAGE__->authz->authz_runmodes(
             one => 'admin',
             two => 'admin',
             );

         # protect only runmodes that start with auth_
         __PACKAGE__->authz->authz_runmodes(
             qr/^authz_/ => 'admin',
             );

         # protect all runmodes that *do not* start with public_
         __PACKAGE__->authz->authz_runmodes(
             qr/^(?!public_)/ => 'admin',
             );

         # preserve the interface from 0.06:
         __PACKAGE__->authz->authz_runmodes(
             [':all' => 'admin'],
             );

   is_authz_runmode
       This method accepts the name of a runmode, and if that runmode requires authorization (ie
       the user needs to be a member of a particular group or has to satisfy some other
       authorization rule) then this method returns the corresponding authorization rule which
       must be satisfied (which could be either a scalar, a list-ref, or a code-ref, depending on
       how the rules were defined).

   new
       This method creates a new CGI::Application::Plugin::Authorization object.  It requires as
       it's only parameter a CGI::Application object.  This method should never be called
       directly, since the "authz" method that is imported into the CGI::Application module will
       take care of creating the CGI::Application::Plugin::Authorization object when it is
       required.

   instance
       This method works the same way as "new", except that it returns the same Authorization
       object for the duration of the request.  This method should never be called directly,
       since the "authz" method that is imported into the CGI::Application module will take care
       of creating the CGI::Application::Plugin::Authorization object when it is required.

   authorize
       This method will test to see if the current user has access to the given resource.  It
       will take the given parameters and test them against the DRIVER classes that have been
       configured.  A true return value means the user should have access to the given resource.

        # is the current user in the admin group
        if ($self->authz->authorize('admingroup')) {
           # perform an admin action
        }

   username
       This method will return the name of the currently logged in user.  It uses three different
       methods to figure out the username:

       GET_USERNAME option
           Use the subroutine provided by the GET_USERNAME option to figure out the current
           username

       CGI::Application::Plugin::Authentication
           See if the CGI::Application::Plugin::Authentication plugin is being used, and retrieve
           the username through this plugin

       REMOTE_USER
           See if the REMOTE_USER environment variable is set and use that value

   drivers
       This method will return a list of driver objects that are used for this authorization
       instance.

   cgiapp
       This will return the underlying CGI::Application object.

   setup_runmodes
       This method is called during the prerun stage to register some custom runmodes that the
       Authentication plugin requires in order to function.

CGI::Application CALLBACKS

       We'll automatically add the "authz_forbidden" run mode if you are using CGI::Application
       4.0 or greater.

       If you are using an older version of CGI::Application you will need to add it yourself.

        sub cgiapp_prerun {
           my $self = shift;

           $self->run_modes( authz_forbidden => \&CGI::Application::Plugin::Authorization::authz_forbidden, );
        }

   prerun_callback
       This method is a CGI::Application prerun callback that will be automatically registered
       for you if you are using CGI::Application 4.0 or greater.  If you are using an older
       version of CGI::Application you will have to create your own cgiapp_prerun method and make
       sure you call this method from there.

        sub cgiapp_prerun {
           my $self = shift;

           $self->CGI::Application::Plugin::Authorization::prerun_callback();
        }

   redirect_to_forbidden
       This method is be called during the prerun stage if the current user is not authorized,
       and they are trying to access an authz runmode.  It will redirect to the page that has
       been configured as the forbidden page, based on the value of FORBIDDEN_RUNMODE or
       FORBIDDEN_URL  If nothing is configured then the default forbidden page will be used.

   forbidden
       This will return a forbidden page.  It checks the configuration to see if there is a
       custom runmode or URL to redirect to, otherwise it calls the builtin authz_forbidden
       runmode.

CGI::Application RUNMODES

   authz_forbidden
       This runmode is provided if you do not want to create your own forbidden runmode.  It will
       display a simple error page to the user.

   authz_dummy_redirect
       This runmode is provided for convenience when an external redirect needs to be done.  It
       just returns an empty string.

EXAMPLE

       In a CGI::Application module:

         package MyCGIApp;

         use base qw(CGI::Application);
         use CGI::Application::Plugin::AutoRunmode;
         use CGI::Application::Plugin::Authentication;
         use CGI::Application::Plugin::Authorization;

         # Configure Authentication
         MyCGIApp->authen->config(
               DRIVER => 'Dummy',
         );
         MyCGIApp->authen->protected_runmodes(qr/^admin_/);

         # Configure Authorization (manages runmode authorization)
         MyCGIApp->authz->config(
             DRIVER => [ 'DBI',
                 DBH         => $self->dbh,
                 TABLES      => ['user', 'usergroup', 'group'],
                 JOIN_ON     => 'user.id = usergroup.user_id AND usergroup.group_id = group.id',
                 CONSTRAINTS => {
                    'user.name'  => '__USERNAME__',
                    'group.name' => '__GROUP__',
                 }
             ],
         );
         MyCGIApp->authz->authz_runmodes(
            [a_runmode => 'a_group'],
            [qr/^admin_/ => 'admin'],
            [':all' => 'all_group'],
            [sub {my $rm = shift; return ($rm eq "dangerous_rm")} => 'super_group'],
         );

         # Configure second Authorization module using a named configuration
         __PACKAGE__->authz('dbaccess')->config(
             DRIVER => [ 'DBI',
                 DBH   => $self->dbh,
                 TABLES      => ['user', 'access'],
                 JOIN_ON     => 'user.id = access.user_id',
                 CONSTRAINTS => {
                     'user.name'      => '__USERNAME__',
                     'access.table'   => '__PARAM_1__',
                     'access.item_id' => '__PARAM_2__'
                 }
             ],
         );

         sub start : Runmode {
           my $self = shift;

         }

         sub admin_one : Runmode {
           my $self = shift;
           # The user will only get here if they are logged in and
           # belong to the admin group

         }

         sub admin_widgets : Runmode {
           my $self = shift;
           # The user will only get here if they are logged in and
           # belong to the admin group

           # Can this user edit this widget in the widgets table?
           my $widget_id = $self->query->param('widget_id');
           return $self->authz->forbidden unless $self->authz('dbaccess')->authorize(widgets => $widget_id);

         }

TODO

       The module is definitely in a usable state, but there are still some parts missing that I
       would like to add in:

       provide easy methods for authorizing runmode access automatically
       allow subroutine attributes to configure authorization for a runmode
       write a tutorial/cookbook to include with the docs

BUGS

       This is alpha software and as such, the features and interface are subject to change.  So
       please check the Changes file when upgrading.

SEE ALSO

       CGI::Application::Plugin::Authentication, CGI::Application, perl(1)

AUTHOR

       Cees Hek <ceeshek@gmail.com>

CREDITS

       Thanks to SiteSuite (http://www.sitesuite.com.au) for funding the development of this
       plugin and for releasing it to the world.

LICENCE AND COPYRIGHT

       Copyright (c) 2005, SiteSuite. All rights reserved.

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

DISCLAIMER OF WARRANTY

       BECAUSE THIS SOFTWARE IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR THE SOFTWARE,
       TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE
       COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE SOFTWARE "AS IS" WITHOUT WARRANTY OF
       ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
       WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO
       THE QUALITY AND PERFORMANCE OF THE SOFTWARE IS WITH YOU. SHOULD THE SOFTWARE PROVE
       DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR, OR CORRECTION.

       IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT
       HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE THE SOFTWARE AS PERMITTED BY
       THE ABOVE LICENCE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL,
       INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE
       SOFTWARE (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR
       LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE SOFTWARE TO OPERATE WITH ANY
       OTHER SOFTWARE), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
       SUCH DAMAGES.

perl v5.12.3                                2011-05-1CGI::Application::Plugin::Authorization(3pm)