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-rw-r--r--extensions/ConfirmEdit/FancyCaptcha/FancyCaptcha.class.php416
1 files changed, 416 insertions, 0 deletions
diff --git a/extensions/ConfirmEdit/FancyCaptcha/FancyCaptcha.class.php b/extensions/ConfirmEdit/FancyCaptcha/FancyCaptcha.class.php
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+++ b/extensions/ConfirmEdit/FancyCaptcha/FancyCaptcha.class.php
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+<?php
+
+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',
+ 'wikiId' => wfWikiId(),
+ 'lockManager' => new NullLockManager( array() ),
+ '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.
+ *
+ * @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() {
+ global $wgOut, $wgEnableAPI;
+
+ // Uses addModuleStyles so it is loaded when JS is disabled.
+ $wgOut->addModuleStyles( 'ext.confirmEdit.fancyCaptcha.styles' );
+
+ $title = SpecialPage::getTitleFor( 'Captcha', 'image' );
+ $index = $this->getCaptchaIndex();
+
+ if ( $wgEnableAPI ) {
+ // Loaded only if JS is enabled
+ $wgOut->addModules( 'ext.confirmEdit.fancyCaptcha' );
+
+ $captchaReload = Html::element(
+ 'small',
+ array(
+ 'class' => 'confirmedit-captcha-reload fancycaptcha-reload'
+ ),
+ wfMessage( 'fancycaptcha-reload-text' )->text()
+ );
+ } else {
+ $captchaReload = '';
+ }
+
+ $form = Html::openElement( 'div' ) .
+ Html::element( 'label', array(
+ 'for' => 'wpCaptchaWord',
+ ),
+ parent::getMessage( 'label' ) . ' ' . wfMessage( 'createacct-captcha' )->text()
+ ) .
+ Html::openElement( 'div', array( 'class' => 'mw-createacct-captcha-container' ) ) .
+ Html::openElement( 'div', array( 'class' => 'mw-createacct-captcha-and-reload' ) ) .
+ Html::openElement( 'div', array( 'class' => 'fancycaptcha-image-container' ) ) .
+ Html::element( 'img', array(
+ 'class' => 'fancycaptcha-image',
+ 'src' => $title->getLocalUrl( 'wpCaptchaId=' . urlencode( $index ) ),
+ 'alt' => ''
+ )
+ ) . $captchaReload . Html::closeElement( 'div' ) . Html::closeElement( 'div' ) . "\n" .
+ Html::element( 'input', array(
+ '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' => 1,
+ 'placeholder' => wfMessage( 'createacct-imgcaptcha-ph' )
+ )
+ ); // tab in before the edit textarea
+ if ( $this->action == 'usercreate' ) {
+ $form .= HTML::element( 'small',array(
+ 'class' => 'mw-createacct-captcha-assisted'
+ ), wfMessage( 'createacct-imgcaptcha-help' )
+ );
+ }
+ $form .= Html::element( 'input', array(
+ 'type' => 'hidden',
+ 'name' => 'wpCaptchaId',
+ 'id' => 'wpCaptchaId',
+ 'value' => $index
+ )
+ ) . Html::closeElement( 'div' ) . Html::closeElement( 'div' ) . "\n";
+
+ return $form;
+ }
+
+ /**
+ * Get captcha index key
+ * @return string captcha ID key
+ */
+ function getCaptchaIndex() {
+ $info = $this->pickImage();
+ if ( !$info ) {
+ throw new Exception( "Ran out of captcha images" );
+ }
+
+ // 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 );
+
+ return $index;
+ }
+
+ /**
+ * 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 = array(); // subdirs actually present...
+ foreach ( $backend->getTopDirectoryList( array( '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( 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?
+ }
+ }
+
+ 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 = 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;
+ }
+ }
+ 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( 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?
+ }
+
+ return $info;
+ }
+
+ /**
+ * @param $directory string
+ * @param $files array
+ * @param $lockouts integer
+ * @return boolean
+ */
+ 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( $key, '1', 600 ) ) {
+ continue; // could not acquire (skip it to avoid race conditions)
+ }
+ }
+ if ( !$backend->fileExists( array( '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 array(
+ 'salt' => $matches[1],
+ 'hash' => $matches[2],
+ 'viewed' => false,
+ );
+ }
+ }
+
+ return false; // none found
+ }
+
+ function showImage() {
+ global $wgOut;
+
+ $wgOut->disable();
+
+ $info = $this->retrieveCaptcha();
+ if ( $info ) {
+ $timestamp = new MWTimestamp();
+ $info['viewed'] = $timestamp->getTimestamp();
+ $this->storeCaptcha( $info );
+
+ $salt = $info['salt'];
+ $hash = $info['hash'];
+
+ return $this->getBackend()->streamFile( array(
+ 'src' => $this->imagePath( $salt, $hash ),
+ 'headers' => array( "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 array( $matches[1], $matches[2] );
+ } else {
+ throw new Exception( "Invalid filename '$basename'.\n" );
+ }
+ }
+
+ /**
+ * Show a message asking the user to enter a captcha on edit
+ * The result will be treated as wiki text
+ *
+ * @param $action string Action being performed
+ * @return string
+ */
+ function getMessage( $action ) {
+ $name = 'fancycaptcha-' . $action;
+ $text = wfMessage( $name )->text();
+ # Obtain a more tailored message, if possible, otherwise, fall back to
+ # the default for edits
+ return wfMessage( $name, $text )->isDisabled() ?
+ wfMessage( 'fancycaptcha-edit' )->text() : $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 ) {
+ $this->getBackend()->quickDelete( array(
+ 'src' => $this->imagePath( $info['salt'], $info['hash'] )
+ ) );
+ }
+
+ return $pass;
+ }
+}