/ 
CGI-Application-Plugin-ProtectCSRF-1.01
River stage zero No dependents
/ CGI::Application::Plugin::ProtectCSRF

NAME

CGI::Application::Plugin::ProtectCSRF - Plug-in protected from CSRF

VERSION

1.01

SYNPSIS

use Your::App;
use base qw(CGI::Application);
use CGI::Application::Plugin::Session; # require!!
use CGI::Application::Plugin::ProtectCSRF;

sub input_form : PublishCSRFID {
  my $self = shift;
  do_something();
}

sub finish : ProtectCSRF {
  my $self = shift;
  $self->clear_csrf_id;
  do_something();
}

DESCRIPTION

CGI::Application::Plugin::ProtectCSRF is C::A::P protected from CSRF.

When CSRF is detected, Forbidden is returned and processing is interrupted.

ACTION

PublishCSRFID

PublishCSRFID is action publishes CSRF ticket. CSRF ticket is published when I define it as an attribute of runmode method publishing CSRF ticket, and it is saved in session. If there is form tag in HTML to display after the processing end, as for runmode method to publish, CSRF ticket is set automatically by hidden field

# publish CSRF ticket
sub input_form : PublishCSRFID {
  my $self = shift;
  return <<HTML;
<form action="foo" method="post">
<input type="text" name="name">
<input type="submit" value="submit!">
<input type="hidden" name="rm" value="finish">
</form>
HTML
}

# display html source
<form action="foo" method="post">
<input type="hidden" name="_csrf_id" value="random string" /> <- insert hidden field
<input type="text" name="name">
<input type="submit" value="submit!">
<input type="hidden" name="rm" value="finish">
</form>

ProtectCSRF

ProtectCSRF is action to protect from CSRF Attack. If session CSRF ticket does not accord with query CSRF ticket, application consideres it to be CSRF attack and refuse to access it. Carry out the processing that you want to perform after having carried out clear_csrf_id method when access it, and it was admitted.

sub finish : ProtectCSRF {
  my $self = shift;
  $self->clear_csrf_id; # require! There is not a meaning unless I do it
  do_something();       # The processing that you want to perform (DB processing etc)
}

METHOD

csrf_id

Get ticket for protect CSRF

Example:

sub input_form : PublishCSRFID {
  my $self = shift;

  my $csrf_id = $self->csrf_id;
  do_something();
}

protect_csrf_config

Initialize ProtectCSRF

Option:

csrf_error_status      : CSRF error status code (default: 200)
csrf_error_mode        : CSRF error runmode name (default: _csrf_error)
csrf_error_tmpl        : CSRF error display html. scalarref or filepath or filehandle (default: $CSRF_ERROR_TMPL - scalarref)
csrf_error_tmpl_param  : CSRF error display html parameter (for HTML::Template)
csrf_id                : CSRF ticket name (default: _csrf_id)
csrf_post_only         : CSRF protect runmode request method check(default:0  1:POST Only)

Example:

sub cgiapp_init {
  my $self = shift;
  $self->tmpl_path("/path/to/template");
  $self->protect_csrf_config(
                         csrf_error_status     => 403, # change forbidden
                         csrf_error_tmpl       => "csrf_error.tmpl",
                         csrf_error_tmpl_param => { TITLE => "CSRF ERROR", MESSAGE => "your access is csrf!"},
                         csrf_id               => "ticket_id",
                         csrf_post_only        => 1
                       );
}

# csrf_error.tmpl
<html><head><title><TMPL_VAR NAME=TITLE ESCAPE=HTML></title></head>
<body>
<h1>CSRF Error</h1>
<span style="color: red"><TMPL_VAR NAME=MESSAGE ESCAPE=HTML></span>
</body>
</html>

clear_csrf_id

Clear csrfid. It is preferable to make it execute after processing ends.

Example :

sub cgiapp_init {
  my $self = shift;
  $self->protect_csrf_config;
}

sub input {
  my $self = shift;
  do_something(). # input form display..
}

sub confirm : PublishCSRFID {
  my $self = shift;
  do_something(). # publish csrf_id and input check and confirm display..
}

sub complete : ProtectCSRF {
  my $self = shift;
  $self->clear_csrf_id(1); # clear csrf_id for CSRF protect
  do_something();          # DB insert etc..
}

CALLBACK

_publish_csrf_id

prerun callback

_csrf_forbidden

prerun callback

_add_csrf_id

postrun callback

CAUTION

It has only the protection function of basic CSRF,and mount other security checks in the application, please.

SEE ALSO

Attribute::Handlers Carp CGI::Application CGI::Application::Plugin::Session Digest::SHA1 Exporter HTML::TokeParser

AUTHOR

Akira Horimoto <kurt0027@gmail.com>

COPYRIGHT

Copyright (C) 2006 - 2008 Akira Horimoto

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