diff options
Diffstat (limited to 'www/wiki/extensions/ConfirmEdit/FancyCaptcha/FancyCaptcha.class.php')
| -rw-r--r-- | www/wiki/extensions/ConfirmEdit/FancyCaptcha/FancyCaptcha.class.php | 465 |
1 files changed, 465 insertions, 0 deletions
diff --git a/www/wiki/extensions/ConfirmEdit/FancyCaptcha/FancyCaptcha.class.php b/www/wiki/extensions/ConfirmEdit/FancyCaptcha/FancyCaptcha.class.php new file mode 100644 index 00000000..3010374f --- /dev/null +++ b/www/wiki/extensions/ConfirmEdit/FancyCaptcha/FancyCaptcha.class.php @@ -0,0 +1,465 @@ +<?php + +use MediaWiki\Auth\AuthenticationRequest; +use MediaWiki\Auth\AuthManager; + +/** + * FancyCaptcha for displaying captchas precomputed by captcha.py + */ +class FancyCaptcha extends SimpleCaptcha { + // used for fancycaptcha-edit, fancycaptcha-addurl, fancycaptcha-badlogin, + // fancycaptcha-accountcreate, fancycaptcha-create, fancycaptcha-sendemail via getMessage() + protected static $messagePrefix = 'fancycaptcha-'; + + /** + * @return FileBackend + */ + public function getBackend() { + global $wgCaptchaFileBackend, $wgCaptchaDirectory; + + if ( $wgCaptchaFileBackend ) { + return FileBackendGroup::singleton()->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 ) { + $modules = []; + + $title = SpecialPage::getTitleFor( 'Captcha', 'image' ); + $info = $this->getCaptcha(); + $index = $this->storeCaptcha( $info ); + + // Loaded only for clients with JS enabled + $modules[] = 'ext.confirmEdit.fancyCaptcha'; + + $captchaReload = Html::element( + 'small', + [ + 'class' => 'confirmedit-captcha-reload fancycaptcha-reload' + ], + wfMessage( 'fancycaptcha-reload-text' )->text() + ); + + $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 string $directory + * @param int $levels + * @param int &$lockouts + * @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 string $directory + * @param int &$lockouts + * @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 string $directory + * @param array $files + * @param int &$lockouts + * @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 string $salt + * @param string $hash + * @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 string $basename + * @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']; + } +} |