/extensions/ConfirmEdit/FancyCaptcha.class.php
PHP | 249 lines | 192 code | 21 blank | 36 comment | 22 complexity | 82f1525090a1d55841c6061179ccbdc5 MD5 | raw file
- <?php
- class FancyCaptcha extends SimpleCaptcha {
- /**
- * Check if the submitted form matches the captcha session data provided
- * by the plugin when the form was generated.
- *
- * @param string $answer
- * @param array $info
- * @return bool
- */
- function keyMatch( $answer, $info ) {
- global $wgCaptchaSecret;
- $digest = $wgCaptchaSecret . $info['salt'] . $answer . $wgCaptchaSecret . $info['salt'];
- $answerHash = substr( md5( $digest ), 0, 16 );
- if ( $answerHash == $info['hash'] ) {
- wfDebug( "FancyCaptcha: answer hash matches expected {$info['hash']}\n" );
- return true;
- } else {
- wfDebug( "FancyCaptcha: answer hashes to $answerHash, expected {$info['hash']}\n" );
- return false;
- }
- }
- function addCaptchaAPI( &$resultArr ) {
- $info = $this->pickImage();
- if ( !$info ) {
- $resultArr['captcha']['error'] = 'Out of images';
- return;
- }
- $index = $this->storeCaptcha( $info );
- $title = SpecialPage::getTitleFor( 'Captcha', 'image' );
- $resultArr['captcha']['type'] = 'image';
- $resultArr['captcha']['mime'] = 'image/png';
- $resultArr['captcha']['id'] = $index;
- $resultArr['captcha']['url'] = $title->getLocalUrl( 'wpCaptchaId=' . urlencode( $index ) );
- }
- /**
- * Insert the captcha prompt into the edit form.
- */
- function getForm() {
- $info = $this->pickImage();
- if ( !$info ) {
- die( "out of captcha images; this shouldn't happen" );
- }
- // Generate a random key for use of this captcha image in this session.
- // This is needed so multiple edits in separate tabs or windows can
- // go through without extra pain.
- $index = $this->storeCaptcha( $info );
- wfDebug( "Captcha id $index using hash ${info['hash']}, salt ${info['salt']}.\n" );
- $title = SpecialPage::getTitleFor( 'Captcha', 'image' );
- return "<p>" .
- Xml::element( 'img', array(
- 'src' => $title->getLocalUrl( 'wpCaptchaId=' . urlencode( $index ) ),
- 'width' => $info['width'],
- 'height' => $info['height'],
- 'alt' => '' ) ) .
- "</p>\n" .
- Xml::element( 'input', array(
- 'type' => 'hidden',
- 'name' => 'wpCaptchaId',
- 'id' => 'wpCaptchaId',
- 'value' => $index ) ) .
- "<p>" .
- Xml::element( 'input', array(
- 'name' => 'wpCaptchaWord',
- 'id' => 'wpCaptchaWord',
- 'tabindex' => 1 ) ) . // tab in before the edit textarea
- "</p>\n";
- }
- /**
- * Select a previously generated captcha image from the queue.
- * @fixme subject to race conditions if lots of files vanish
- * @return mixed tuple of (salt key, text hash) or false if no image to find
- */
- function pickImage() {
- global $wgCaptchaDirectory, $wgCaptchaDirectoryLevels;
- return $this->pickImageDir(
- $wgCaptchaDirectory,
- $wgCaptchaDirectoryLevels );
- }
- function pickImageDir( $directory, $levels ) {
- if ( $levels ) {
- $dirs = array();
- // Check which subdirs are actually present...
- $dir = opendir( $directory );
- while ( false !== ( $entry = readdir( $dir ) ) ) {
- if ( ctype_xdigit( $entry ) && strlen( $entry ) == 1 ) {
- $dirs[] = $entry;
- }
- }
- closedir( $dir );
- $place = mt_rand( 0, count( $dirs ) - 1 );
- // In case all dirs are not filled,
- // cycle through next digits...
- for ( $j = 0; $j < count( $dirs ); $j++ ) {
- $char = $dirs[( $place + $j ) % count( $dirs )];
- $return = $this->pickImageDir( "$directory/$char", $levels - 1 );
- if ( $return ) {
- return $return;
- }
- }
- // Didn't find any images in this directory... empty?
- return false;
- } else {
- return $this->pickImageFromDir( $directory );
- }
- }
- function pickImageFromDir( $directory ) {
- if ( !is_dir( $directory ) ) {
- return false;
- }
- $n = mt_rand( 0, $this->countFiles( $directory ) - 1 );
- $dir = opendir( $directory );
- $count = 0;
- $entry = readdir( $dir );
- $pick = false;
- while ( false !== $entry ) {
- $entry = readdir( $dir );
- if ( preg_match( '/^image_([0-9a-f]+)_([0-9a-f]+)\\.png$/', $entry, $matches ) ) {
- $size = getimagesize( "$directory/$entry" );
- $pick = array(
- 'salt' => $matches[1],
- 'hash' => $matches[2],
- 'width' => $size[0],
- 'height' => $size[1],
- 'viewed' => false,
- );
- if ( $count++ == $n ) {
- break;
- }
- }
- }
- closedir( $dir );
- return $pick;
- }
- /**
- * Count the number of files in a directory.
- * @return int
- */
- function countFiles( $dirname ) {
- $dir = opendir( $dirname );
- $count = 0;
- while ( false !== ( $entry = readdir( $dir ) ) ) {
- if ( $entry != '.' && $entry != '..' ) {
- $count++;
- }
- }
- closedir( $dir );
- return $count;
- }
- function showImage() {
- global $wgOut;
- $wgOut->disable();
- $info = $this->retrieveCaptcha();
- if ( $info ) {
- /*
- // Be a little less restrictive for now; in at least some circumstances,
- // Konqueror tries to reload the image even if you haven't navigated
- // away from the page.
- if( $info['viewed'] ) {
- wfHttpError( 403, 'Access Forbidden', "Can't view captcha image a second time." );
- return false;
- }
- */
- $info['viewed'] = wfTimestamp();
- $this->storeCaptcha( $info );
- $salt = $info['salt'];
- $hash = $info['hash'];
- $file = $this->imagePath( $salt, $hash );
- if ( file_exists( $file ) ) {
- global $IP;
- require_once "$IP/includes/StreamFile.php";
- header( "Cache-Control: private, s-maxage=0, max-age=3600" );
- wfStreamFile( $file );
- return true;
- }
- }
- wfHttpError( 500, 'Internal Error', 'Requested bogus captcha image' );
- return false;
- }
- function imagePath( $salt, $hash ) {
- global $wgCaptchaDirectory, $wgCaptchaDirectoryLevels;
- $file = $wgCaptchaDirectory;
- $file .= DIRECTORY_SEPARATOR;
- for ( $i = 0; $i < $wgCaptchaDirectoryLevels; $i++ ) {
- $file .= $hash { $i } ;
- $file .= DIRECTORY_SEPARATOR;
- }
- $file .= "image_{$salt}_{$hash}.png";
- return $file;
- }
- /**
- * Show a message asking the user to enter a captcha on edit
- * The result will be treated as wiki text
- *
- * @param $action Action being performed
- * @return string
- */
- function getMessage( $action ) {
- $name = 'fancycaptcha-' . $action;
- $text = wfMsg( $name );
- # Obtain a more tailored message, if possible, otherwise, fall back to
- # the default for edits
- return wfEmptyMsg( $name, $text ) ? wfMsg( 'fancycaptcha-edit' ) : $text;
- }
- /**
- * Delete a solved captcha image, if $wgCaptchaDeleteOnSolve is true.
- */
- function passCaptcha() {
- global $wgCaptchaDeleteOnSolve;
- $info = $this->retrieveCaptcha(); // get the captcha info before it gets deleted
- $pass = parent::passCaptcha();
- if ( $pass && $wgCaptchaDeleteOnSolve ) {
- $filename = $this->imagePath( $info['salt'], $info['hash'] );
- if ( file_exists( $filename ) ) {
- unlink( $filename );
- }
- }
- return $pass;
- }
- }