diff options
Diffstat (limited to 'extensions/ConfirmEdit/FancyCaptcha.class.php')
| -rw-r--r-- | extensions/ConfirmEdit/FancyCaptcha.class.php | 304 |
1 files changed, 207 insertions, 97 deletions
diff --git a/extensions/ConfirmEdit/FancyCaptcha.class.php b/extensions/ConfirmEdit/FancyCaptcha.class.php index 97a89045..f559f0f3 100644 --- a/extensions/ConfirmEdit/FancyCaptcha.class.php +++ b/extensions/ConfirmEdit/FancyCaptcha.class.php @@ -2,6 +2,53 @@ class FancyCaptcha extends SimpleCaptcha { /** + * @return FileBackend + */ + public function getBackend() { + global $wgCaptchaFileBackend, $wgCaptchaDirectory; + + if ( $wgCaptchaFileBackend ) { + return FileBackendGroup::singleton()->get( $wgCaptchaFileBackend ); + } else { + static $backend = null; + if ( !$backend ) { + $backend = new FSFileBackend( array( + 'name' => 'captcha-backend', + 'lockManager' => 'nullLockManager', + 'containerPaths' => array( 'captcha-render' => $wgCaptchaDirectory ), + 'fileMode' => 777 + ) ); + } + return $backend; + } + } + + /** + * @return integer Estimate of the number of captchas files + */ + public function estimateCaptchaCount() { + global $wgCaptchaDirectoryLevels; + + $factor = 1; + $sampleDir = $this->getBackend()->getRootStoragePath() . '/captcha-render'; + if ( $wgCaptchaDirectoryLevels >= 1 ) { // 1/16 sample if 16 shards + $sampleDir .= '/' . dechex( mt_rand( 0, 15 ) ); + $factor = 16; + } + if ( $wgCaptchaDirectoryLevels >= 3 ) { // 1/256 sample if 4096 shards + $sampleDir .= '/' . dechex( mt_rand( 0, 15 ) ); + $factor = 256; + } + + $count = 0; + foreach ( $this->getBackend()->getFileList( array( 'dir' => $sampleDir ) ) as $file ) { + ++$count; + } + + return ( $count * $factor ); + } + + /** * Check if the submitted form matches the captcha session data provided * by the plugin when the form was generated. * @@ -71,7 +118,7 @@ class FancyCaptcha extends SimpleCaptcha { '<p>' . Html::element( 'label', array( 'for' => 'wpCaptchaWord', - ), parent::getMessage( 'label' ) . wfMsg( 'colon-separator' ) ) . + ), parent::getMessage( 'label' ) . wfMessage( 'colon-separator' )->text() ) . Html::element( 'input', array( 'name' => 'wpCaptchaWord', 'id' => 'wpCaptchaWord', @@ -85,94 +132,151 @@ class FancyCaptcha extends SimpleCaptcha { /** * 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 ); + protected function pickImage() { + global $wgCaptchaDirectoryLevels; + + $lockouts = 0; // number of times another process claimed a file before this one + $baseDir = $this->getBackend()->getRootStoragePath() . '/captcha-render'; + return $this->pickImageDir( $baseDir, $wgCaptchaDirectoryLevels, $lockouts ); } - function pickImageDir( $directory, $levels ) { - if ( $levels ) { - $dirs = array(); + /** + * @param $directory string + * @param $levels integer + * @param $lockouts integer + * @return Array|bool + */ + protected function pickImageDir( $directory, $levels, &$lockouts ) { + global $wgMemc; - // Check which subdirs are actually present... - $dir = opendir( $directory ); - if ( !$dir ) { - return false; - } - while ( false !== ( $entry = readdir( $dir ) ) ) { + if ( $levels <= 0 ) { // $directory has regular files + return $this->pickImageFromDir( $directory, $lockouts ); + } + + $backend = $this->getBackend(); + + $key = "fancycaptcha:dirlist:{$backend->getWikiId()}:" . sha1( $directory ); + $dirs = $wgMemc->get( $key ); // check cache + if ( !is_array( $dirs ) ) { // cache miss + $dirs = array(); // subdirs actually present... + foreach ( $backend->getTopDirectoryList( array( 'dir' => $directory ) ) as $entry ) { 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; - } + wfDebug( "Cache miss for $directory subdirectory listing.\n" ); + $wgMemc->set( $key, $dirs, 86400 ); + } + + if ( !count( $dirs ) ) { + // Remove this directory if empty so callers don't keep looking here + $backend->clean( array( 'dir' => $directory ) ); + return false; // none found + } + + $place = mt_rand( 0, count( $dirs ) - 1 ); // pick a random subdir + // In case all dirs are not filled, cycle through next digits... + for ( $j = 0; $j < count( $dirs ); $j++ ) { + $char = $dirs[( $place + $j ) % count( $dirs )]; + $info = $this->pickImageDir( "$directory/$char", $levels - 1, $lockouts ); + if ( $info ) { + return $info; // found a captcha + } else { + wfDebug( "Could not find captcha in $directory.\n" ); + $wgMemc->delete( $key ); // files changed on disk? } - // Didn't find any images in this directory... empty? - return false; - } else { - return $this->pickImageFromDir( $directory ); } + + return false; // didn't find any images in this directory... empty? } - function pickImageFromDir( $directory ) { - if ( !is_dir( $directory ) ) { - return false; - } - $n = mt_rand( 0, $this->countFiles( $directory ) - 1 ); - $dir = opendir( $directory ); + /** + * @param $directory string + * @param $lockouts integer + * @return Array|bool + */ + protected function pickImageFromDir( $directory, &$lockouts ) { + global $wgMemc; - $count = 0; + $backend = $this->getBackend(); - $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 ) { + $key = "fancycaptcha:filelist:{$backend->getWikiId()}:" . sha1( $directory ); + $files = $wgMemc->get( $key ); // check cache + if ( !is_array( $files ) ) { // cache miss + $files = array(); // captcha files + foreach ( $backend->getTopFileList( array( 'dir' => $directory ) ) as $entry ) { + $files[] = $entry; + if ( count( $files ) >= 500 ) { // sanity + wfDebug( 'Skipping some captchas; $wgCaptchaDirectoryLevels set too low?.' ); break; } } + $wgMemc->set( $key, $files, 86400 ); + wfDebug( "Cache miss for $directory captcha listing.\n" ); + } + + if ( !count( $files ) ) { + // Remove this directory if empty so callers don't keep looking here + $backend->clean( array( 'dir' => $directory ) ); + return false; + } + + $info = $this->pickImageFromList( $directory, $files, $lockouts ); + if ( !$info ) { + wfDebug( "Could not find captcha in $directory.\n" ); + $wgMemc->delete( $key ); // files changed on disk? } - closedir( $dir ); - return $pick; + + return $info; } /** - * Count the number of files in a directory. - * @return int + * @param $directory string + * @param $files array + * @param $lockouts integer + * @return boolean */ - function countFiles( $dirname ) { - $dir = opendir( $dirname ); - $count = 0; - while ( false !== ( $entry = readdir( $dir ) ) ) { - if ( $entry != '.' && $entry != '..' ) { - $count++; + protected function pickImageFromList( $directory, array $files, &$lockouts ) { + global $wgMemc, $wgCaptchaDeleteOnSolve; + + if ( !count( $files ) ) { + return false; // none found + } + + $backend = $this->getBackend(); + $place = mt_rand( 0, count( $files ) - 1 ); // pick a random file + $misses = 0; // number of files in listing that don't actually exist + for ( $j = 0; $j < count( $files ); $j++ ) { + $entry = $files[( $place + $j ) % count( $files )]; + if ( preg_match( '/^image_([0-9a-f]+)_([0-9a-f]+)\\.png$/', $entry, $matches ) ) { + if ( $wgCaptchaDeleteOnSolve ) { // captcha will be deleted when solved + $key = "fancycaptcha:filelock:{$backend->getWikiId()}:" . sha1( $entry ); + // Try to claim this captcha for 10 minutes (for the user to solve)... + if ( ++$lockouts <= 10 && !$wgMemc->add( $key, '1', 600 ) ) { + continue; // could not acquire (skip it to avoid race conditions) + } + } + $fsFile = $backend->getLocalReference( array( 'src' => "$directory/$entry" ) ); + if ( !$fsFile || !$fsFile->exists() ) { + if ( ++$misses >= 5 ) { // too many files in the listing don't exist + break; // listing cache too stale? break out so it will be cleared + } + continue; // try next file + } + $size = getimagesize( $fsFile->getPath() ); + return array( + 'salt' => $matches[1], + 'hash' => $matches[2], + 'width' => $size[0], + 'height' => $size[1], + 'viewed' => false, + ); } } - closedir( $dir ); - return $count; + + return false; // none found } function showImage() { @@ -182,60 +286,67 @@ class FancyCaptcha extends SimpleCaptcha { $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(); + $timestamp = new MWTimestamp(); + $info['viewed'] = $timestamp->getTimestamp(); $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; - } + + return $this->getBackend()->streamFile( array( + 'src' => $this->imagePath( $salt, $hash ), + 'headers' => array( "Cache-Control: private, s-maxage=0, max-age=3600" ) + ) )->isOK(); } + wfHttpError( 500, 'Internal Error', 'Requested bogus captcha image' ); return false; } - function imagePath( $salt, $hash ) { - global $wgCaptchaDirectory, $wgCaptchaDirectoryLevels; - $file = $wgCaptchaDirectory; - $file .= DIRECTORY_SEPARATOR; + /** + * @param $salt string + * @param $hash string + * @return string + */ + public function imagePath( $salt, $hash ) { + global $wgCaptchaDirectoryLevels; + + $file = $this->getBackend()->getRootStoragePath() . '/captcha-render/'; for ( $i = 0; $i < $wgCaptchaDirectoryLevels; $i++ ) { - $file .= $hash { $i } ; - $file .= DIRECTORY_SEPARATOR; + $file .= $hash{ $i } . '/'; } $file .= "image_{$salt}_{$hash}.png"; + return $file; } /** + * @param $basename string + * @return Array (salt, hash) + * @throws MWException + */ + public function hashFromImageName( $basename ) { + if ( preg_match( '/^image_([0-9a-f]+)_([0-9a-f]+)\\.png$/', $basename, $matches ) ) { + return array( $matches[1], $matches[2] ); + } else { + throw new MWException( "Invalid filename '$basename'.\n" ); + } + } + + /** * 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 + * @param $action string Action being performed * @return string */ function getMessage( $action ) { $name = 'fancycaptcha-' . $action; - $text = wfMsg( $name ); + $text = wfMessage( $name )->text(); # Obtain a more tailored message, if possible, otherwise, fall back to # the default for edits - return wfEmptyMsg( $name, $text ) ? wfMsg( 'fancycaptcha-edit' ) : $text; + return wfMessage( $name, $text )->isDisabled() ? + wfMessage( 'fancycaptcha-edit' )->text() : $text; } /** @@ -248,10 +359,9 @@ class FancyCaptcha extends SimpleCaptcha { $pass = parent::passCaptcha(); if ( $pass && $wgCaptchaDeleteOnSolve ) { - $filename = $this->imagePath( $info['salt'], $info['hash'] ); - if ( file_exists( $filename ) ) { - unlink( $filename ); - } + $this->getBackend()->quickDelete( array( + 'src' => $this->imagePath( $info['salt'], $info['hash'] ) + ) ); } return $pass; |