NAME¶
CGI::Application::Plugin::Authentication - Authentication framework for
CGI::Application
VERSION¶
This document describes CGI::Application::Plugin::Authentication version 0.20
SYNOPSIS¶
package MyCGIApp;
use base qw(CGI::Application); # make sure this occurs before you load the plugin
use CGI::Application::Plugin::Authentication;
MyCGIApp->authen->config(
DRIVER => [ 'Generic', { user1 => '123' } ],
);
MyCGIApp->authen->protected_runmodes('myrunmode');
sub myrunmode {
my $self = shift;
# The user should be logged in if we got here
my $username = $self->authen->username;
}
DESCRIPTION¶
CGI::Application::Plugin::Authentication adds the ability to authenticate users
in your CGI::Application modules. It imports one method called 'authen' into
your CGI::Application module. Through the authen method you can call all the
methods of the CGI::Application::Plugin::Authentication plugin.
There are two main decisions that you need to make when using this module. How
will the usernames and password be verified (i.e. from a database, LDAP,
etc...), and how can we keep the knowledge that a user has already logged in
persistent, so that they will not have to enter their credentials again on the
next request (i.e. how do we 'Store' the authentication information across
requests).
Choosing a Driver¶
There are three drivers that are included with the distribution. Also, there is
built in support for all of the Authen::Simple modules (search CPAN for
Authen::Simple for more information). This should be enough to cover
everyone's needs.
If you need to authenticate against a source that is not provided, you can use
the Generic driver which will accept either a hash of username/password pairs,
or an array of arrays of credentials, or a subroutine reference that can
verify the credentials. So through the Generic driver you should be able to
write your own verification system. There is also a Dummy driver, which
blindly accepts any credentials (useful for testing). See the
CGI::Application::Plugin::Authentication::Driver::Generic,
CGI::Application::Plugin::Authentication::Driver::DBI and,
CGI::Application::Plugin::Authentication::Driver::Dummy docs for more
information on how to use these drivers. And see the Authen::Simple suite of
modules for information on those drivers.
Choosing a Store¶
The Store modules keep information about the authentication status of the user
persistent across multiple requests. The information that is stored in the
store include the username, and the expiry time of the login. There are two
Store modules included with this distribution. A Session based store, and a
Cookie based store. If your application is already using Sessions (through the
CGI::Application::Plugin::Session module), then I would recommend that you use
the Session store for authentication. If you are not using the Session plugin,
then you can use the Cookie store. The Cookie store keeps all the
authentication in a cookie, which contains a checksum to ensure that users can
not change the information.
If you do not specify which Store module you wish to use, the plugin will try to
determine the best one for you.
Login page¶
The Authentication plugin comes with a default login page that can be used if
you do not want to create a custom login page. This login form will
automatically be used if you do not provide either a LOGIN_URL or
LOGIN_RUNMODE parameter in the configuration. If you plan to create your own
login page, I would recommend that you start with the HTML code for the
default login page, so that your login page will contain the correct form
fields and hidden fields.
Ticket based authentication¶
This Authentication plugin can handle ticket based authentication systems as
well. All that is required of you is to write a Store module that can
understand the contents of the ticket. The Authentication plugin will require
at least the 'username' to be retrieved from the ticket. A Ticket based
authentication scheme will not need a Driver module at all, since the actual
verification of credentials is done by an external authentication system,
possibly even on a different host. You will need to specify the location of
the login page using the LOGIN_URL configuration variable, and unauthenticated
users will automatically be redirected to your ticket authentication login
page.
EXPORTED METHODS¶
authen¶
This is the only method exported from this module. Everything is controlled
through this method call, which will return a
CGI::Application::Plugin::Authentication object, or just the class name if
called as a class method. When using the plugin, you will always first call
$self->authen or __PACKAGE__->authen and then the method you wish to
invoke. For example:
__PACKAGE__->authen->config(
LOGIN_RUNMODE => 'login',
);
- or -
$self->authen->protected_runmodes(qw(one two));
METHODS¶
config¶
This method is used to configure the CGI::Application::Plugin::Authentication
module. It can be called as an object method, or as a class method. Calling
this function, will not itself generate cookies or session ids.
The following parameters are accepted:
- DRIVER
- Here you can choose which authentication module(s) you want to use to
perform the authentication. For simplicity, you can leave off the
CGI::Application::Plugin::Authentication::Driver:: part when specifying
the DRIVER name 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 rest of the values in the array will be considered options
for the driver. You can provide multiple drivers which will be used, in
order, to check the credentials until a valid response is received.
DRIVER => 'Dummy' # let anyone in regardless of the password
- or -
DRIVER => [ 'DBI',
DBH => $self->dbh,
TABLE => 'user',
CONSTRAINTS => {
'user.name' => '__CREDENTIAL_1__',
'MD5:user.password' => '__CREDENTIAL_2__'
},
],
- or -
DRIVER => [
[ 'Generic', { user1 => '123' } ],
[ 'Generic', sub { my ($u, $p) = @_; is_prime($p) ? 1 : 0 } ]
],
- or -
DRIVER => [ 'Authen::Simple::LDAP',
host => 'ldap.company.com',
basedn => 'ou=People,dc=company,dc=net'
],
- STORE
- Here you can choose how we store the authenticated information after a
user has successfully logged in. We need to store the username so that on
the next request we can tell the user has already logged in, and we do not
have to present them with another login form. If you do not provide the
STORE option, then the plugin will look to see if you are using the
CGI::Application::Plugin::Session module and based on that info use either
the Session module, or fall back on the Cookie module. If the module
requires extra parameters, you can pass an array reference that contains
as the first parameter the name of the module, and the rest of the array
should contain key value pairs of options for this module. These storage
modules generally live under the
CGI::Application::Plugin::Authentication::Store:: name-space, and this
part of the package name can be left off when specifying the STORE
parameter.
STORE => 'Session'
- or -
STORE => ['Cookie',
NAME => 'MYAuthCookie',
SECRET => 'FortyTwo',
EXPIRY => '1d',
]
- POST_LOGIN_RUNMODE
- Here you can specify a runmode that the user will be redirected to if they
successfully login.
POST_LOGIN_RUNMODE => 'welcome'
- POST_LOGIN_URL
- Here you can specify a URL that the user will be redirected to if they
successfully login. If both POST_LOGIN_URL and POST_LOGIN_RUNMODE are
specified, then the latter will take precedence.
POST_LOGIN_URL => 'http://example.com/start.cgi'
- POST_LOGIN_CALLBACK
- A code reference that is executed after login processing but before
POST_LOGIN_RUNMODE or redirecting to POST_LOGIN_URL. This is normally a
method in your CGI::Application application and as such the
CGI::Application object is passed as a parameter.
POST_LOGIN_CALLBACK => \&update_login_date
and later in your code:
sub update_login_date {
my $self = shift;
return unless($self->authen->is_authenticated);
...
}
- LOGIN_RUNMODE
- Here you can specify a runmode that the user will be redirected to if they
need to login.
LOGIN_RUNMODE => 'login'
- LOGIN_URL
- If your login 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 need
to login. If both LOGIN_URL and LOGIN_RUNMODE are specified, then the
latter will take precedence.
LOGIN_URL => 'http://example.com/login.cgi'
- LOGOUT_RUNMODE
- Here you can specify a runmode that the user will be redirected to if they
ask to logout.
LOGOUT_RUNMODE => 'logout'
- LOGOUT_URL
- If your logout 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 ask
to logout. If both LOGOUT_URL and LOGOUT_RUNMODE are specified, then the
latter will take precedence.
LOGIN_URL => 'http://example.com/logout.html'
- DETAINT_URL_REGEXP
- This is a regular expression used to detaint URLs used in the login form.
By default it will be set to
^([\w\_\%\?\&\;\-\/\@\.\+\$\=\#\:\!\*\"\'\(\)\,]+)$
This regular expression is based upon the document
http://www.w3.org/Addressing/URL/url-spec.txt. You could set it to a more
specific regular expression to limit the domains to which users could be
directed.
- DETAINT_USERNAME_REGEXP
- This is a regular expression used to detaint the username parameter used
in the login form. By default it will be set to
^([\w\_]+)$
- CREDENTIALS
- Set this to the list of form fields where the user will type in their
username and password. By default this is set to ['authen_username',
'authen_password']. The form field names should be set to a value that you
are not likely to use in any other forms. This is important because this
plugin will automatically look for query parameters that match these
values on every request to see if a user is trying to log in. So if you
use the same parameter names on a user management page, you may
inadvertently perform a login when that was not intended. Most of the
Driver modules will return the first CREDENTIAL as the username, so make
sure that you list the username field first. This option can be ignored if
you use the built in login box
CREDENTIALS => 'authen_password'
- or -
CREDENTIALS => [ 'authen_username', 'authen_domain', 'authen_password' ]
- LOGIN_SESSION_TIMEOUT
- This option can be used to tell the system when to force the user to
re-authenticate. There are a few different possibilities that can all be
used concurrently:
- IDLE_FOR
- If this value is set, a re-authentication will be forced if the user was
idle for more then x amount of time.
- EVERY
- If this value is set, a re-authentication will be forced every x amount of
time.
- CUSTOM
- This value can be set to a subroutine reference that returns true if the
session should be timed out, and false if it is still active. This can
allow you to be very selective about how the timeout system works. The
authen object will be passed in as the only parameter.
Time values are specified in seconds. You can also specify the time by using a
number with the following suffixes (m h d w), which represent minutes, hours,
days and weeks. The default is 0 which means the login will never timeout.
Note that the login is also dependent on the type of STORE that is used. If the
Session store is used, and the session expires, then the login will also
automatically expire. The same goes for the Cookie store.
For backwards compatibility, if you set LOGIN_SESSION_TIMEOUT to a time value
instead of a hashref, it will be treated as an IDLE_FOR time out.
# force re-authentication if idle for more than 15 minutes
LOGIN_SESSION_TIMEOUT => '15m'
# Everyone must re-authentication if idle for more than 30 minutes
# also, everyone must re-authentication at least once a day
# and root must re-authentication if idle for more than 5 minutes
LOGIN_SESSION_TIMEOUT => {
IDLE_FOR => '30m',
EVERY => '1d',
CUSTOM => sub {
my $authen = shift;
return ($authen->username eq 'root' && (time() - $authen->last_access) > 300) ? 1 : 0;
}
}
- RENDER_LOGIN
- This value can be set to a subroutine reference that returns the HTML of a
login form. The subroutine reference overrides the default call to
login_box. The subroutine is normally a method in your CGI::Application
application and as such the CGI::Application object is passed as the first
parameter.
RENDER_LOGIN => \&login_form
and later in your code:
sub login_form {
my $self = shift;
...
return $html
}
- LOGIN_FORM
- You can set this option to customize the login form that is created when a
user needs to be authenticated. If you wish to replace the entire login
form with a completely custom version, then just set LOGIN_RUNMODE to
point to your custom runmode.
All of the parameters listed below are optional, and a reasonable default
will be used if left blank:
- DISPLAY_CLASS (default: Classic)
- the class used to display the login form. The alternative is
"Basic" which aims for XHTML compliance and leaving style to
CSS. See CGI::Application::Plugin::Authentication::Display for more
details.
- TITLE (default: Sign In)
- the heading at the top of the login box
- USERNAME_LABEL (default: User Name)
- the label for the user name input
- PASSWORD_LABEL (default: Password)
- the label for the password input
- SUBMIT_LABEL (default: Sign In)
- the label for the submit button
- COMMENT (default: Please enter your username and password in the fields
below.)
- a message provided on the first login attempt
- REMEMBERUSER_OPTION (default: 1)
- provide a checkbox to offer to remember the users name in a cookie so that
their user name will be pre-filled the next time they log in
- REMEMBERUSER_LABEL (default: Remember User Name)
- the label for the remember user name checkbox
- REMEMBERUSER_COOKIENAME (default: CAPAUTHTOKEN)
- the name of the cookie where the user name will be saved
- REGISTER_URL (default: <none>)
- the URL for the register new account link
- REGISTER_LABEL (default: Register Now!)
- the label for the register new account link
- FORGOTPASSWORD_URL (default: <none>)
- the URL for the forgot password link
- FORGOTPASSWORD_LABEL (default: Forgot Password?)
- the label for the forgot password link
- INVALIDPASSWORD_MESSAGE (default: Invalid username or password<br
/>(login attempt %d)
- a message given when a login failed
- INCLUDE_STYLESHEET (default: 1)
- use this to disable the built in style-sheet for the login box so you can
provide your own custom styles
- FORM_SUBMIT_METHOD (default: post)
- use this to get the form to submit using 'get' instead of 'post'
- FOCUS_FORM_ONLOAD (default: 1)
- use this to automatically focus the login form when the page loads so a
user can start typing right away.
- BASE_COLOUR (default: #445588)
- This is the base colour that will be used in the included login box. All
other colours are automatically calculated based on this colour (unless
you hardcode the colour values). In order to calculate other colours, you
will need the Color::Calc module. If you do not have the Color::Calc
module, then you will need to use fixed values for all of the colour
options. All colour values besides the BASE_COLOUR can be simple
percentage values (including the % sign). For example if you set the
LIGHTER_COLOUR option to 80%, then the calculated colour will be 80%
lighter than the BASE_COLOUR.
- LIGHT_COLOUR (default: 50% or #a2aac4)
- A colour that is lighter than the base colour.
- LIGHTER_COLOUR (default: 75% or #d0d5e1)
- A colour that is another step lighter than the light colour.
- DARK_COLOUR (default: 30% or #303c5f)
- A colour that is darker than the base colour.
- DARKER_COLOUR (default: 60% or #1b2236)
- A colour that is another step darker than the dark colour.
- GREY_COLOUR (default: #565656)
- A grey colour that is calculated by desaturating the base colour.
protected_runmodes¶
This method takes a list of runmodes that are to be protected by authentication.
If a user tries to access one of these runmodes, then they will be redirected
to a login page unless they are properly logged in. The runmode names can be a
list of simple strings, regular expressions, or special directives that start
with a colon. This method is cumulative, so if it is called multiple times,
the new values are added to existing entries. It returns a list of all entries
that have been saved so far. Calling this function, will not itself generate
cookies or session ids.
- :all - All runmodes in this module will require authentication
# match all runmodes
__PACKAGE__->authen->protected_runmodes(':all');
# only protect runmodes one two and three
__PACKAGE__->authen->protected_runmodes(qw(one two three));
# protect only runmodes that start with auth_
__PACKAGE__->authen->protected_runmodes(qr/^auth_/);
# protect all runmodes that *do not* start with public_
__PACKAGE__->authen->protected_runmodes(qr/^(?!public_)/);
is_protected_runmode¶
This method accepts the name of a runmode, and will tell you if that runmode is
a protected runmode (i.e. does a user need to be authenticated to access this
runmode). Calling this function, will not itself generate cookies or session
ids.
redirect_after_login¶
This method is be called during the prerun stage to redirect the user to the
page that has been configured as the destination after a successful login. The
location is determined as follows:
- POST_LOGIN_RUNMODE
- If the POST_LOGIN_RUNMODE config parameter is set, that run mode will be
the chosen location.
- POST_LOGIN_URL
- If the above fails and the POST_LOGIN_URL config parameter is set, then
there will be a 302 redirection to that location.
- destination
- If the above fails and there is a destination query parameter, which must
a taint check against the DETAINT_URL_REGEXP config parameter, then there
will be a 302 redirection to that location.
- original destination
- If all the above fail then there the originally requested page will be
delivered.
redirect_to_login¶
This method is be called during the prerun stage if the current user is not
logged in, and they are trying to access a protected runmode. It will redirect
to the page that has been configured as the login page, based on the value of
LOGIN_RUNMODE or LOGIN_URL If nothing is configured a simple login page will
be automatically provided.
redirect_to_logout¶
This method is called during the prerun stage if the user has requested to be
logged out. It will redirect to the page that has been configured as the
logout page, based on the value of LOGOUT_RUNMODE or LOGOUT_URL If nothing is
configured, the page will redirect to the website homepage.
setup_runmodes¶
This method is called during the prerun stage to register some custom runmodes
that the Authentication plugin requires in order to function. Calling this
function, will not itself generate cookies or session ids.
last_login¶
This will return return the time of the last login for this user
my $last_login = $self->authen->last_login;
This function will initiate a session or cookie if one has not been created
already.
last_access¶
This will return return the time of the last access for this user
my $last_access = $self->authen->last_access;
This function will initiate a session or cookie if one has not been created
already.
is_login_timeout¶
This will return true or false depending on whether the users login status just
timed out
$self->add_message('login session timed out') if $self->authen->is_login_timeout;
This function will initiate a session or cookie if one has not been created
already.
is_authenticated¶
This will return true or false depending on the login status of this user
assert($self->authen->is_authenticated); # The user should be logged in if we got here
This function will initiate a session or cookie if one has not been created
already.
login_attempts¶
This method will return the number of failed login attempts have been made by
this user since the last successful login. This is not a number that can be
trusted, as it is dependent on the underlying store to be able to return the
correct value for this user. For example, if the store uses a cookie based
session, the user trying to login could delete their cookies, and hence get a
new session which will not have any login attempts listed. The number will be
cleared upon a successful login. This function will initiate a session or
cookie if one has not been created already.
username¶
This will return the username of the currently logged in user, or undef if no
user is currently logged in.
my $username = $self->authen->username;
This function will initiate a session or cookie if one has not been created
already.
is_new_login¶
This will return true or false depending on if this is a fresh login
$self->log->info("New Login") if $self->authen->is_new_login;
This function will initiate a session or cookie if one has not been created
already.
credentials¶
This method will return the names of the form parameters that will be looked for
during a login. By default they are authen_username and authen_password, but
these values can be changed by supplying the CREDENTIALS parameters in the
configuration. Calling this function, will not itself generate cookies or
session ids.
logout¶
This will attempt to logout the user. If during a request the Authentication
module sees a parameter called 'authen_logout', it will automatically call
this method to log out the user.
$self->authen->logout();
This function will initiate a session or cookie if one has not been created
already.
drivers¶
This method will return a list of driver objects that are used for verifying the
login credentials. Calling this function, will not itself generate cookies or
session ids.
store¶
This method will return a store object that is used to store information about
the status of the authentication across multiple requests. This function will
initiate a session or cookie if one has not been created already.
initialize¶
This does most of the heavy lifting for the Authentication plugin. It will check
to see if the user is currently attempting to login by looking for the
credential form fields in the query object. It will load the required driver
objects and authenticate the user. It is OK to call this method multiple times
as it checks to see if it has already been executed and will just return
without doing anything if called multiple times. This allows us to call
initialize as late as possible in the request so that no unnecessary work is
done.
The user will be logged out by calling the "logout()" method if the
login session has been idle for too long, if it has been too long since the
last login, or if the login has timed out. If you need to know if a user was
logged out because of a time out, you can call the
"is_login_timeout" method.
If all goes well, a true value will be returned, although it is usually not
necessary to check.
This function will initiate a session or cookie if one has not been created
already.
display¶
This method will return the CGI::Application::Plugin::Authentication::Display
object, creating and caching it if necessary.
login_box¶
This method will return the HTML for a login box that can be embedded into
another page. This is the same login box that is used in the default
authen_login runmode that the plugin provides.
This function will initiate a session or cookie if one has not been created
already.
new¶
This method creates a new CGI::Application::Plugin::Authentication object. It
requires as it's only parameter a CGI::Application object. This method should
never be called directly, since the 'authen' method that is imported into the
CGI::Application module will take care of creating the
CGI::Application::Plugin::Authentication object when it is required. Calling
this function, will not itself generate cookies or session ids.
instance¶
This method works the same way as 'new', except that it returns the same
Authentication object for the duration of the request. This method should
never be called directly, since the 'authen' method that is imported into the
CGI::Application module will take care of creating the
CGI::Application::Plugin::Authentication object when it is required. Calling
this function, will not itself generate cookies or session ids.
CGI::Application CALLBACKS¶
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::Authentication::prerun_callback();
}
CGI::Application RUNMODES¶
authen_login_runmode¶
This runmode is provided if you do not want to create your own login runmode. It
will display a simple login form for the user, which can be replaced by
assigning RENDER_LOGIN a coderef that returns the HTML.
authen_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:
use base qw(CGI::Application);
use CGI::Application::Plugin::AutoRunmode;
use CGI::Application::Plugin::Session;
use CGI::Application::Plugin::Authentication;
__PACKAGE__->authen->config(
DRIVER => [ 'Generic', { user1 => '123' } ],
STORE => 'Session',
LOGOUT_RUNMODE => 'start',
);
__PACKAGE__->authen->protected_runmodes(qr/^auth_/, 'one');
sub start : RunMode {
my $self = shift;
}
sub one : RunMode {
my $self = shift;
# The user will only get here if they are logged in
}
sub auth_two : RunMode {
my $self = shift;
# This is also protected because of the
# regexp call to protected_runmodes above
}
COMPATIBILITY WITH CGI::Application::Plugin::ActionDispatch¶
The prerun callback has been modified so that it will check for the presence of
a prerun mode. This is for compatibility with
CGI::Application::Plugin::ActionDispatch. This change should be considered
experimental. It is necessary to load the ActionDispatch module so that the
two prerun callbacks will be called in the correct order.
RECOMMENDED USAGE¶
- CSS
- The best practice nowadays is generally considered to be to not have CSS
embedded in HTML. Thus it should be best to set LOGIN_FORM ->
DISPLAY_CLASS to 'Basic'.
- Post login destination
- Of the various means of selecting a post login destination the most secure
would seem to be POST_LOGIN_URL. The "destination" parameter
could potentially be hijacked by hackers. The POST_LOGIN_RUNMODE parameter
requires a hidden parameter that could potentially be hijacked.
- Taint mode
- Do run your code under taint mode. It should help protect your application
against a number of attacks.
- URL and username checking
- Please set the "DETAINT_URL_REGEXP" and
"DETAINT_USERNAME_REGEXP" parameters as tightly as possible. In
particular you should prevent the destination parameter being used to
redirect authenticated users to external sites; unless of course that is
what you want in which case that site should be the only possible external
site.
- The login form
- The HTML currently generated does not seem to be standards compliant as
per RT bug 58023. Also the default login form includes hidden forms which
could conceivably be hijacked. Set LOGIN_FORM -> DISPLAY_CLASS to
'Basic' to fix this.
TODO¶
There are lots of things that can still be done to improve this plugin. If
anyone else is interested in helping out feel free to dig right in. Many of
these things don't need my input, but if you want to avoid duplicated efforts,
send me a note, and I'll let you know of anyone else is working in the same
area.
- review the code for security bugs and report
- complete the separation of presentation and logic
- write a tutorial
- build more Drivers (Class::DBI, LDAP, Radius, etc...)
- Add support for method attributes to identify runmodes that require
authentication
- finish the test suite
- provide more example code
- clean up the documentation
- build a DB driver that builds it's own table structure. This can be used
by people that don't have their own user database to work with, and could
include a simple user management application.
BUGS¶
This is alpha software and as such, the features and interface are subject to
change. So please check the Changes file when upgrading.
Some of the test scripts appear to be incompatible with versions of Devel::Cover
later than 0.65.
SEE ALSO¶
CGI::Application,
perl(1)
AUTHOR¶
Author: Cees Hek <ceeshek@gmail.com>; Co-maintainer: Nicholas Bamber
<nicholas@periapt.co.uk>.
CREDITS¶
Thanks to SiteSuite <
http://www.sitesuite.com.au> for funding the
development of this plugin and for releasing it to the world.
Thanks to Christian Walde for suggesting changes to fix the incompatibility with
CGI::Application::Plugin::ActionDispatch and for help with github.
Thanks to Alexandr Ciornii for pointing out some typos.
LICENCE AND COPYRIGHT¶
Copyright (c) 2005, SiteSuite. All rights reserved. Copyright (c) 2010, Nicholas
Bamber. (Portions of the code).
This module is free software; you can redistribute it and/or modify it under the
same terms as Perl itself.
The background images in the default login forms are used courtesy of
www.famfamfam.com <
http://www.famfamfam.com/lab/icons/silk/>. Those
icons are issued under the Creative Commons Attribution 3.0 License
<
http://creativecommons.org/licenses/by/3.0/>. Those icons are
copyrighted 2006 by Mark James <mjames at gmail dot com>
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