Plugin for visual confirmation of new user registration, to prevent automated scripts to create users and spam your wiki with their url's to get a better google ranking.

Syntax Rules


Plugin Settings

Plugin settings are stored as preferences variables. To reference a plugin setting write %<plugin>_<setting>%, i.e. %INTERWIKIPLUGIN_SHORTDESCRIPTION%

Plugin Installation Instructions

Note: You do not need to install anything on the browser to use this plugin. The following instructions are for the administrator who installs the plugin on the server where TWiki is running.

         <Directory "/path/to/twiki/pub/visualconfirm/db">
           deny from all
              <td valign="top" align="right"><IMG SRC="%VISUALCONFIRMURL%">: <br /> (..)   </td>
              <td><input type="hidden" name="Twk1VisualConfirmHash" value="%VISUALCONFIRMHASH%">
                  <input type="text" name="Twk1VisualConfirm" size="5"></td>

Manually patching the register binary

Find the line in bin/register that says:

    # everything OK

Insert the code below directly BEFORE that line:

    # check valid visual confirmation
    for( $x = 0; $x < $formLen; $x++ ) {
        unless(not($formDataName[$x] eq "Visual Confirm Hash"));
        unless(not($formDataName[$x] eq "Visual Confirm"));


    dbmopen(%database, &TWiki::getPubDir()."/visualconfirm/db/hashes" ,0644);

    if(!defined($database{$vcHash})) {
      $url = &TWiki::getOopsUrl( $webName, $topic, "oopsregvisualconfirm",
        "The visual confirmation has expired.");
      TWiki::redirect( $query, $url );

    my ($time,$txt)=split(',',$database{$vcHash});

    if(not(lc($txt) eq lc($vcTxt))) {
      $url = &TWiki::getOopsUrl( $webName, $topic, "oopsregvisualconfirm",
        "The character string you entered for visual confirmation is incorrect.");
      TWiki::redirect( $query, $url );


Further Development

Plugin Info

Plugin Author: TWiki:Main.KoenMartens
Plugin Version: 03 Jan 2006 (V1.001)
Change History:  
07 Oct 2005: Initial version
10 Oct 2005: Strip hash and text from arguments to register binary, or they will end up in the newly created user topic.
03 Jan 2006: Fixed some problems with expiry, also optimised according to TWiki:TWiki.TWikiPlugins#FastPluginHints.
TWiki Dependency: $TWiki::Plugins::VERSION 1.024
CPAN Dependencies: GD, Digest::MD5
Other Dependencies: none
Perl Version: 5.005
License: GPL (GNU General Public License)
TWiki:Plugins/Benchmark: GoodStyle 98%, FormattedSearch 98%, TWikiRegistration (patched) 85%
Plugin Home:

Related Topics: TWikiPreferences, TWikiPlugins

-- TWiki:Main.KoenMartens - 07 Oct 2005