get( $wgCaptchaFileBackend ); } else { static $backend = null; if ( !$backend ) { $backend = new FSFileBackend( [ 'name' => 'captcha-backend', 'wikiId' => wfWikiID(), 'lockManager' => new NullLockManager( [] ), 'containerPaths' => [ 'captcha-render' => $wgCaptchaDirectory ], 'fileMode' => 777, 'obResetFunc' => 'wfResetOutputBuffers', 'streamMimeFunc' => [ 'StreamFile', 'contentTypeFromPath' ] ] ); } return $backend; } } /** * @deprecated Use getCaptchaCount instead for an accurate figure * @return int Number of captcha files */ public function estimateCaptchaCount() { wfDeprecated( __METHOD__ ); return $this->getCaptchaCount(); } /** * @return int Number of captcha files */ public function getCaptchaCount() { $backend = $this->getBackend(); $files = $backend->getFileList( [ 'dir' => $backend->getRootStoragePath() . '/captcha-render' ] ); return iterator_count( $files ); } /** * 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; } } /** * @param array $resultArr */ function addCaptchaAPI( &$resultArr ) { $info = $this->pickImage(); if ( !$info ) { $resultArr['captcha']['error'] = 'Out of images'; return; } $index = $this->storeCaptcha( $info ); $title = SpecialPage::getTitleFor( 'Captcha', 'image' ); $resultArr['captcha'] = $this->describeCaptchaType(); $resultArr['captcha']['id'] = $index; $resultArr['captcha']['url'] = $title->getLocalURL( 'wpCaptchaId=' . urlencode( $index ) ); } /** * @return array */ public function describeCaptchaType() { return [ 'type' => 'image', 'mime' => 'image/png', ]; } /** * @param int $tabIndex * @return array */ function getFormInformation( $tabIndex = 1 ) { global $wgEnableAPI; $modules = []; $title = SpecialPage::getTitleFor( 'Captcha', 'image' ); $info = $this->getCaptcha(); $index = $this->storeCaptcha( $info ); if ( $wgEnableAPI ) { // Loaded only if JS is enabled $modules[] = 'ext.confirmEdit.fancyCaptcha'; $captchaReload = Html::element( 'small', [ 'class' => 'confirmedit-captcha-reload fancycaptcha-reload' ], wfMessage( 'fancycaptcha-reload-text' )->text() ); } else { $captchaReload = ''; } $form = Html::openElement( 'div' ) . Html::element( 'label', [ 'for' => 'wpCaptchaWord', ], wfMessage( 'captcha-label' )->text() . ' ' . wfMessage( 'fancycaptcha-captcha' )->text() ) . Html::openElement( 'div', [ 'class' => 'fancycaptcha-captcha-container' ] ) . Html::openElement( 'div', [ 'class' => 'fancycaptcha-captcha-and-reload' ] ) . Html::openElement( 'div', [ 'class' => 'fancycaptcha-image-container' ] ) . Html::element( 'img', [ 'class' => 'fancycaptcha-image', 'src' => $title->getLocalURL( 'wpCaptchaId=' . urlencode( $index ) ), 'alt' => '' ] ) . $captchaReload . Html::closeElement( 'div' ) . Html::closeElement( 'div' ) . "\n" . Html::element( 'input', [ 'name' => 'wpCaptchaWord', 'class' => 'mw-ui-input', 'id' => 'wpCaptchaWord', 'type' => 'text', 'size' => '12', // max_length in captcha.py plus fudge factor 'autocomplete' => 'off', 'autocorrect' => 'off', 'autocapitalize' => 'off', 'required' => 'required', 'tabindex' => $tabIndex, 'placeholder' => wfMessage( 'fancycaptcha-imgcaptcha-ph' ) ] ); // tab in before the edit textarea if ( $this->action == 'createaccount' ) { // use raw element, because the message can contain links or some other html $form .= Html::rawElement( 'small', [ 'class' => 'mw-createacct-captcha-assisted' ], wfMessage( 'createacct-imgcaptcha-help' )->parse() ); } $form .= Html::element( 'input', [ 'type' => 'hidden', 'name' => 'wpCaptchaId', 'id' => 'wpCaptchaId', 'value' => $index ] ) . Html::closeElement( 'div' ) . Html::closeElement( 'div' ) . "\n"; return [ 'html' => $form, 'modules' => $modules, // Uses addModuleStyles so it is loaded when JS is disabled. 'modulestyles' => [ 'ext.confirmEdit.fancyCaptcha.styles' ], ]; } /** * Select a previously generated captcha image from the queue. * @return mixed tuple of (salt key, text hash) or false if no image to find */ 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 ); } /** * @param $directory string * @param $levels integer * @param $lockouts integer * @return array|bool */ protected function pickImageDir( $directory, $levels, &$lockouts ) { global $wgMemc; 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 ) || !count( $dirs ) ) { // cache miss $dirs = []; // subdirs actually present... foreach ( $backend->getTopDirectoryList( [ 'dir' => $directory ] ) as $entry ) { if ( ctype_xdigit( $entry ) && strlen( $entry ) == 1 ) { $dirs[] = $entry; } } wfDebug( "Cache miss for $directory subdirectory listing.\n" ); if ( count( $dirs ) ) { $wgMemc->set( $key, $dirs, 86400 ); } } if ( !count( $dirs ) ) { // Remove this directory if empty so callers don't keep looking here $backend->clean( [ '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... $fancyCount = count( $dirs ); for ( $j = 0; $j < $fancyCount; $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? } } return false; // didn't find any images in this directory... empty? } /** * @param $directory string * @param $lockouts integer * @return array|bool */ protected function pickImageFromDir( $directory, &$lockouts ) { global $wgMemc; $backend = $this->getBackend(); $key = "fancycaptcha:filelist:{$backend->getWikiId()}:" . sha1( $directory ); $files = $wgMemc->get( $key ); // check cache if ( !is_array( $files ) || !count( $files ) ) { // cache miss $files = []; // captcha files foreach ( $backend->getTopFileList( [ 'dir' => $directory ] ) as $entry ) { $files[] = $entry; if ( count( $files ) >= 500 ) { // sanity wfDebug( 'Skipping some captchas; $wgCaptchaDirectoryLevels set too low?.' ); break; } } if ( count( $files ) ) { $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( [ '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? } return $info; } /** * @param $directory string * @param $files array * @param $lockouts integer * @return array|bool */ 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 $fancyImageCount = count( $files ); for ( $j = 0; $j < $fancyImageCount; $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( $key, '1', 600 ) ) { continue; // could not acquire (skip it to avoid race conditions) } } if ( !$backend->fileExists( [ 'src' => "$directory/$entry" ] ) ) { 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 } return [ 'salt' => $matches[1], 'hash' => $matches[2], 'viewed' => false, ]; } } return false; // none found } /** * @return bool|StatusValue */ function showImage() { global $wgOut, $wgRequest; $wgOut->disable(); $index = $wgRequest->getVal( 'wpCaptchaId' ); $info = $this->retrieveCaptcha( $index ); if ( $info ) { $timestamp = new MWTimestamp(); $info['viewed'] = $timestamp->getTimestamp(); $this->storeCaptcha( $info ); $salt = $info['salt']; $hash = $info['hash']; return $this->getBackend()->streamFile( [ 'src' => $this->imagePath( $salt, $hash ), 'headers' => [ "Cache-Control: private, s-maxage=0, max-age=3600" ] ] )->isOK(); } wfHttpError( 400, 'Request Error', 'Requested bogus captcha image' ); return false; } /** * @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 } . '/'; } $file .= "image_{$salt}_{$hash}.png"; return $file; } /** * @param $basename string * @return array (salt, hash) * @throws Exception */ public function hashFromImageName( $basename ) { if ( preg_match( '/^image_([0-9a-f]+)_([0-9a-f]+)\\.png$/', $basename, $matches ) ) { return [ $matches[1], $matches[2] ]; } else { throw new Exception( "Invalid filename '$basename'.\n" ); } } /** * Delete a solved captcha image, if $wgCaptchaDeleteOnSolve is true. * @inheritdoc */ protected function passCaptcha( $index, $word ) { global $wgCaptchaDeleteOnSolve; $info = $this->retrieveCaptcha( $index ); // get the captcha info before it gets deleted $pass = parent::passCaptcha( $index, $word ); if ( $pass && $wgCaptchaDeleteOnSolve ) { $this->getBackend()->quickDelete( [ 'src' => $this->imagePath( $info['salt'], $info['hash'] ) ] ); } return $pass; } /** * Returns an array with 'salt' and 'hash' keys. Hash is * md5( $wgCaptchaSecret . $salt . $answer . $wgCaptchaSecret . $salt )[0..15] * @return array * @throws Exception When a captcha image cannot be produced. */ public function getCaptcha() { $info = $this->pickImage(); if ( !$info ) { throw new UnderflowException( 'Ran out of captcha images' ); } return $info; } /** * @param array $captchaData * @param string $id * @return string */ public function getCaptchaInfo( $captchaData, $id ) { $title = SpecialPage::getTitleFor( 'Captcha', 'image' ); return $title->getLocalURL( 'wpCaptchaId=' . urlencode( $id ) ); } /** * @param array $requests * @param array $fieldInfo * @param array $formDescriptor * @param string $action */ public function onAuthChangeFormFields( array $requests, array $fieldInfo, array &$formDescriptor, $action ) { /** @var CaptchaAuthenticationRequest $req */ $req = AuthenticationRequest::getRequestByClass( $requests, CaptchaAuthenticationRequest::class, true ); if ( !$req ) { return; } // HTMLFancyCaptchaField will include this unset( $formDescriptor['captchaInfo' ] ); $formDescriptor['captchaWord'] = [ 'class' => HTMLFancyCaptchaField::class, 'imageUrl' => $this->getCaptchaInfo( $req->captchaData, $req->captchaId ), 'label-message' => $this->getMessage( $this->action ), 'showCreateHelp' => in_array( $action, [ AuthManager::ACTION_CREATE, AuthManager::ACTION_CREATE_CONTINUE ], true ), ] + $formDescriptor['captchaWord']; } }