diff -r 000000000000 -r d970ebf37754 wp/wp-trackback.php
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/wp/wp-trackback.php	Wed Nov 06 03:21:17 2013 +0000
@@ -0,0 +1,127 @@
+<?php
+/**
+ * Handle Trackbacks and Pingbacks Sent to WordPress
+ *
+ * @since 0.71
+ *
+ * @package WordPress
+ * @subpackage Trackbacks
+ */
+
+if (empty($wp)) {
+	require_once( dirname( __FILE__ ) . '/wp-load.php' );
+	wp( array( 'tb' => '1' ) );
+}
+
+/**
+ * Response to a trackback.
+ *
+ * Responds with an error or success XML message.
+ *
+ * @since 0.71
+ *
+ * @param int|bool $error         Whether there was an error.
+ *                                Default '0'. Accepts '0' or '1'.
+ * @param string   $error_message Error message if an error occurred.
+ */
+function trackback_response($error = 0, $error_message = '') {
+	header('Content-Type: text/xml; charset=' . get_option('blog_charset') );
+	if ($error) {
+		echo '<?xml version="1.0" encoding="utf-8"?'.">\n";
+		echo "<response>\n";
+		echo "<error>1</error>\n";
+		echo "<message>$error_message</message>\n";
+		echo "</response>";
+		die();
+	} else {
+		echo '<?xml version="1.0" encoding="utf-8"?'.">\n";
+		echo "<response>\n";
+		echo "<error>0</error>\n";
+		echo "</response>";
+	}
+}
+
+// Trackback is done by a POST.
+$request_array = 'HTTP_POST_VARS';
+
+if ( !isset($_GET['tb_id']) || !$_GET['tb_id'] ) {
+	$tb_id = explode('/', $_SERVER['REQUEST_URI']);
+	$tb_id = intval( $tb_id[ count($tb_id) - 1 ] );
+}
+
+$tb_url  = isset($_POST['url'])     ? $_POST['url']     : '';
+$charset = isset($_POST['charset']) ? $_POST['charset'] : '';
+
+// These three are stripslashed here so they can be properly escaped after mb_convert_encoding().
+$title     = isset($_POST['title'])     ? wp_unslash($_POST['title'])      : '';
+$excerpt   = isset($_POST['excerpt'])   ? wp_unslash($_POST['excerpt'])    : '';
+$blog_name = isset($_POST['blog_name']) ? wp_unslash($_POST['blog_name'])  : '';
+
+if ($charset)
+	$charset = str_replace( array(',', ' '), '', strtoupper( trim($charset) ) );
+else
+	$charset = 'ASCII, UTF-8, ISO-8859-1, JIS, EUC-JP, SJIS';
+
+// No valid uses for UTF-7.
+if ( false !== strpos($charset, 'UTF-7') )
+	die;
+
+// For international trackbacks.
+if ( function_exists('mb_convert_encoding') ) {
+	$title     = mb_convert_encoding($title, get_option('blog_charset'), $charset);
+	$excerpt   = mb_convert_encoding($excerpt, get_option('blog_charset'), $charset);
+	$blog_name = mb_convert_encoding($blog_name, get_option('blog_charset'), $charset);
+}
+
+// Now that mb_convert_encoding() has been given a swing, we need to escape these three.
+$title     = wp_slash($title);
+$excerpt   = wp_slash($excerpt);
+$blog_name = wp_slash($blog_name);
+
+if ( is_single() || is_page() )
+	$tb_id = $posts[0]->ID;
+
+if ( !isset($tb_id) || !intval( $tb_id ) )
+	trackback_response(1, 'I really need an ID for this to work.');
+
+if (empty($title) && empty($tb_url) && empty($blog_name)) {
+	// If it doesn't look like a trackback at all.
+	wp_redirect(get_permalink($tb_id));
+	exit;
+}
+
+if ( !empty($tb_url) && !empty($title) ) {
+	header('Content-Type: text/xml; charset=' . get_option('blog_charset') );
+
+	if ( !pings_open($tb_id) )
+		trackback_response(1, 'Sorry, trackbacks are closed for this item.');
+
+	$title =  wp_html_excerpt( $title, 250, '&#8230;' );
+	$excerpt = wp_html_excerpt( $excerpt, 252, '&#8230;' );
+
+	$comment_post_ID = (int) $tb_id;
+	$comment_author = $blog_name;
+	$comment_author_email = '';
+	$comment_author_url = $tb_url;
+	$comment_content = "<strong>$title</strong>\n\n$excerpt";
+	$comment_type = 'trackback';
+
+	$dupe = $wpdb->get_results( $wpdb->prepare("SELECT * FROM $wpdb->comments WHERE comment_post_ID = %d AND comment_author_url = %s", $comment_post_ID, $comment_author_url) );
+	if ( $dupe )
+		trackback_response(1, 'We already have a ping from that URL for this post.');
+
+	$commentdata = compact('comment_post_ID', 'comment_author', 'comment_author_email', 'comment_author_url', 'comment_content', 'comment_type');
+
+	wp_new_comment($commentdata);
+	$trackback_id = $wpdb->insert_id;
+
+	/**
+	 * Fires after a trackback is added to a post.
+	 *
+	 * @since 1.2.0
+	 *
+	 * @param int $trackback_id Trackback ID.
+	 */
+	do_action( 'trackback_post', $trackback_id );
+	trackback_response( 0 );
+}