addMessages( array(
'captcha-short' =>
"Your edit includes new URL links; as a protection against automated " .
"spam, you'll need to type in the words that appear in this image:\n" .
" ([[Special:Captcha/help|What is this?]])",
'captchahelp-title' =>
'Captcha help',
'captchahelp-text' =>
"Web sites that accept postings from the public, like this wiki, " .
"are often abused by spammers who use automated tools to post their " .
"links to many sites. While these spam links can be removed, they " .
"are a significant nuisance." .
"\n\n" .
"Sometimes, especially when adding new web links to a page, " .
"the wiki may show you an image of colored or distorted text and " .
"ask you to type the words shown. Since this is a task that's hard " .
"to automate, it will allow most real humans to make their posts " .
"while stopping most spammers and other robotic attackers." .
"\n\n" .
"Unfortunately this may inconvenience users with limited vision or " .
"using text-based or speech-based browsers. At the moment we do not " .
"have an audio alternative available. Please contact the site " .
"administrators for assistance if this is unexpectedly preventing " .
"you from making legitimate posts." .
"\n\n" .
"Hit the 'back' button in your browser to return to the page editor." ) );
SpecialPage::addPage( new SpecialPage( 'Captcha', false,
/*listed*/ false, /*function*/ false, /*file*/ false ) );
$wgCaptcha = new $wgCaptchaClass();
$wgHooks['EditFilter'][] = array( &$wgCaptcha, 'confirmEdit' );
}
/**
* Entry point for Special:Captcha
*/
function wfSpecialCaptcha( $par = null ) {
global $wgCaptcha;
switch( $par ) {
case "image":
return $wgCaptcha->showImage();
case "help":
default:
return $wgCaptcha->showHelp();
}
}
class SimpleCaptcha {
/**
* @param EditPage $editPage
* @param string $newtext
* @param string $section
* @return bool true if the captcha should run
*/
function shouldCheck( &$editPage, $newtext, $section ) {
global $wgUser;
if( $wgUser->isAllowed( 'skipcaptcha' ) ) {
wfDebug( "SimpleCaptcha: user group allows skipping captcha\n" );
return false;
}
global $wgEmailAuthentication, $ceAllowConfirmedEmail;
if( $wgEmailAuthentication && $ceAllowConfirmedEmail &&
$wgUser->isEmailConfirmed() ) {
wfDebug( "SimpleCaptcha: user has confirmed mail, skipping captcha\n" );
return false;
}
global $wgCaptchaTriggers;
if( !empty( $wgCaptchaTriggers['edit'] ) ) {
// Check on all edits
wfDebug( "SimpleCaptcha: checking all edits...\n" );
return true;
}
if( !empty( $wgCaptchaTriggers['addurl'] ) ) {
// Only check edits that add URLs
$oldtext = $this->loadText( $editPage, $section );
$oldLinks = $this->findLinks( $oldtext );
$newLinks = $this->findLinks( $newtext );
$addedLinks = array_diff( $newLinks, $oldLinks );
$numLinks = count( $addedLinks );
if( $numLinks > 0 ) {
global $wgUser, $wgTitle;
wfDebugLog( "captcha", sprintf( "ConfirmEdit: %dx url trigger by %s at [[%s]]: %s",
$numLinks,
$wgUser->getName(),
$wgTitle->getPrefixedText(),
implode( ", ", $addedLinks ) ) );
return true;
}
}
return false;
}
function confirmEdit( &$editPage, $newtext, $section ) {
if( $this->shouldCheck( $editPage, $newtext, $section ) ) {
if( $this->keyMatch() ) {
wfDebug( "ConfirmEdit given proper key from form, passing.\n" );
return true;
} else {
wfDebug( "ConfirmEdit missing form key, prompting.\n" );
$editPage->showEditForm( array( &$this, 'formCallback' ) );
return false;
}
} else {
wfDebug( "ConfirmEdit: no new links.\n" );
return true;
}
}
function keyMatch() {
if( !isset( $_SESSION['ceAnswerVar'] ) ) {
wfDebug( "ConfirmEdit no session captcha key set, this is new visitor.\n" );
return false;
}
global $wgRequest;
return $wgRequest->getVal( $_SESSION['ceAnswerVar'] ) == $_SESSION['ceAnswer'];
}
function formCallback( &$out ) {
$source = 'ceSource' . mt_rand();
$dest = 'ceConfirm' . mt_rand();
$a = mt_rand(0, 100);
$b = mt_rand(0, 10);
$op = mt_rand(0, 1) ? '+' : '-';
$test = "$a $op $b";
$answer = ($op == '+') ? ($a + $b) : ($a - $b);
$_SESSION['ceAnswer'] = $answer;
$_SESSION['ceAnswerVar'] = $dest;
$out->addWikiText( wfMsg( "captcha-short" ) );
$out->addHTML( << =
END
);
}
function loadText( $editPage, $section ) {
$rev = Revision::newFromTitle( $editPage->mTitle );
if( is_null( $rev ) ) {
return "";
} else {
$text = $rev->getText();
if( $section != '' ) {
return Article::getSection( $text, $section );
} else {
return $text;
}
}
}
function findLinks( $text ) {
$regex = '/((?:' . HTTP_PROTOCOLS . ')' . EXT_LINK_URL_CLASS . '+)/';
if( preg_match_all( $regex, $text, $matches, PREG_PATTERN_ORDER ) ) {
return $matches[1];
} else {
return array();
}
}
function showHelp() {
global $wgOut, $ceAllowConfirmedEmail;
$wgOut->setPageTitle( wfMsg( 'captchahelp-title' ) );
$wgOut->addWikiText( wfMsg( 'captchahelp-text' ) );
}
}
} # End invocation guard
?>