NAME

Catalyst::Authentication::Credential::RemoteHTTP - Authenticate against remote HTTP server

VERSION

version 0.05

SYNOPSIS

package MyApp::Controller::Auth;

use Catalyst qw/
  Authentication
  /;

sub login : Local {
    my ( $self, $c ) = @_;

    $c->authenticate( { username => $c->req->param('username'),
                        password => $c->req->param('password') });
}

DESCRIPTION

This authentication credential checker takes authentication information (most often a username) and a password, and attempts to validate the username and password provided against a remote http server - ie against another web server.

This is useful for environments where you want to have a single source of authentication information, but are not able to conveniently use a networked authentication mechanism such as LDAP.

CONFIGURATION

# example
__PACKAGE__->config(
    'Plugin::Authentication' => {
                default_realm => 'members',
                realms => {
                    members => {
                        credential => {
                            class => 'RemoteHTTP',
                            url => 'http://intranet.company.com/authenticated.html',
                            password_field => 'password',
                            username_prefix => 'MYDOMAIN\\',
                            http_keep_alive => 1,
                            defer_find_user => 1,
                        },
                        ...
                },
    },
);

class

The classname used for Credential. This is part of Catalyst::Plugin::Authentication and is the method by which Catalyst::Authentication::Credential::RemoteHTTP is loaded as the credential validator. For this module to be used, this must be set to 'RemoteHTTP'.

url

The URL that is used to authenticate the user. The module attempts to fetch this URL using a HEAD request (to prevent dragging a large page across the network) with the credentials given. If this fails then the authentication fails. If no URL is supplied in the config, then an exception is thrown on startup.

username_field

The field in the authentication hash that contains the username. This may vary, but is most likely 'username'. In fact, this is so common that if this is left out of the config, it defaults to 'username'.

password_field

The field in the authentication hash that contains the password. This may vary, but is most likely 'password'. In fact, this is so common that if this is left out of the config, it defaults to 'password'.

username_prefix

This is an optional prefix to the username, which is added to the username before it is used for authenticating to the remote http server. It may be used (for example) to apply a domain to the authenticated username.

username_suffix

This is an optional suffix to the username, which is added to the username before it is used for authenticating to the remote http server. It may be used (for example) to apply a domain to the authenticated username.

http_keep_alive

If http_keep_alive is set then keep_alive is set on the connections to the remote http server. This is required if you are using NTLM authentication (since an additional encryption nonce is passed in the http negotiation). It is optional, but normally harmless, for other forms of authentication.

defer_find_user

Normally the associated user store is queried for user information before the remote http authentication takes place.

However if, for example, you are using a Catalyst::Authentication::Store::DBIx::Class store with the auto_create_user option, then you can end up with invalid users added to the store. If defer_find_user is set true then the remote http authentication occurs before the user is queried against the store, ensuring that any users passed to the store are known to be valid to the remote http server.

METHODS

There are no publicly exported routines in the RemoteHTTP module (or indeed in most credential modules.) However, below is a description of the routines required by Catalyst::Plugin::Authentication for all credential modules.

new( $config, $app, $realm )

Instantiate a new RemoteHTTP object using the configuration hash provided in $config. A reference to the application is provided as the second argument.

authenticate( $authinfo, $c )

Try to log a user in, receives a hashref containing authentication information as the first argument, and the current context as the second.

JUSTIFICATION

Why would you use this module rather than one of the similar ones?

This module gives a combination of authentication against a remote http server, but maintains a local user store. This allows your authentication to be delegated, but the authorization (for example allocation and use of roles) to be determined by the local user store.

Nearly all the other alternatives require you to combine your authentication and authorization databases.

Catalyst::Authentication::Credential::HTTP::Proxy has a similar basis, but requires you to use HTTP basic authentication for the application, which may not be appropriate.

NTLM NOTES

There are a number of issues relating to NTLM authentication. In particular the supporting modules can be rather picky. To make NTLM authentication work you must have an installed copy of libwww-perl that includes LWP::Authen::Ntlm (some linux distributions may drop this component as it gives you additional dependency requirements over the basic LWP package).

Additionally you require Authen::NTLM of version 1.02 or later. There are 2 different CPAN module distributions that provide this module - but only one of them has the appropriate version number.

Finally, if you are using NTLM-1.02 then you need to apply the patch described in RT entry 9521 http://rt.cpan.org/Ticket/Display.html?id=9521.

When using NTLM authentication the configuration option http_keep_alive must be set true - otherwise the session to the remote server is not maintained and the authentication nonce will be lost between sessions.

You may also need to set username_prefix or username_suffix to set the correct domain for the authentication, unless the username as given to your application includes the domain information.

ACKNOWLEDGEMENTS

Daisuke Murase <typester@cpan.org> - original Catalyst::Plugin::Authentication::Store::HTTP used as the base for a previous version of this module.

The code framework was taken from Catalyst::Authentication::Credential::Password

Tomas Doran (t0m) <t0m@state51.co.uk> - Fixups to best practice guidelines

INSTALLATION

See perlmodinstall for information and options on installing Perl modules.

BUGS AND LIMITATIONS

You can make new bug reports, and view existing ones, through the web interface at http://rt.cpan.org/Public/Dist/Display.html?Name=Catalyst-Authentication-Credential-RemoteHTTP.

AVAILABILITY

The project homepage is https://metacpan.org/release/Catalyst-Authentication-Credential-RemoteHTTP.

The latest version of this module is available from the Comprehensive Perl Archive Network (CPAN). Visit http://www.perl.com/CPAN/ to find a CPAN site near you, or see https://metacpan.org/module/Catalyst::Authentication::Credential::RemoteHTTP/.

AUTHOR

Nigel Metheringham <nigelm@cpan.org>

COPYRIGHT AND LICENSE

This software is copyright (c) 2012 by Nigel Metheringham <nigelm@cpan.org>.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.