1 <?php

     2 /**

     3  * Handle Trackbacks and Pingbacks Sent to WordPress

     4  *

     5  * @since 0.71

     6  *

     7  * @package WordPress

     8  * @subpackage Trackbacks

     9  */

    10 

    11 if (empty($wp)) {

    12 	require_once( dirname( __FILE__ ) . '/wp-load.php' );

    13 	wp( array( 'tb' => '1' ) );

    14 }

    15 

    16 /**

    17  * Response to a trackback.

    18  *

    19  * Responds with an error or success XML message.

    20  *

    21  * @since 0.71

    22  *

    23  * @param int|bool $error         Whether there was an error.

    24  *                                Default '0'. Accepts '0' or '1'.

    25  * @param string   $error_message Error message if an error occurred.

    26  */

    27 function trackback_response($error = 0, $error_message = '') {

    28 	header('Content-Type: text/xml; charset=' . get_option('blog_charset') );

    29 	if ($error) {

    30 		echo '<?xml version="1.0" encoding="utf-8"?'.">\n";

    31 		echo "<response>\n";

    32 		echo "<error>1</error>\n";

    33 		echo "<message>$error_message</message>\n";

    34 		echo "</response>";

    35 		die();

    36 	} else {

    37 		echo '<?xml version="1.0" encoding="utf-8"?'.">\n";

    38 		echo "<response>\n";

    39 		echo "<error>0</error>\n";

    40 		echo "</response>";

    41 	}

    42 }

    43 

    44 // Trackback is done by a POST.

    45 $request_array = 'HTTP_POST_VARS';

    46 

    47 if ( !isset($_GET['tb_id']) || !$_GET['tb_id'] ) {

    48 	$tb_id = explode('/', $_SERVER['REQUEST_URI']);

    49 	$tb_id = intval( $tb_id[ count($tb_id) - 1 ] );

    50 }

    51 

    52 $tb_url  = isset($_POST['url'])     ? $_POST['url']     : '';

    53 $charset = isset($_POST['charset']) ? $_POST['charset'] : '';

    54 

    55 // These three are stripslashed here so they can be properly escaped after mb_convert_encoding().

    56 $title     = isset($_POST['title'])     ? wp_unslash($_POST['title'])      : '';

    57 $excerpt   = isset($_POST['excerpt'])   ? wp_unslash($_POST['excerpt'])    : '';

    58 $blog_name = isset($_POST['blog_name']) ? wp_unslash($_POST['blog_name'])  : '';

    59 

    60 if ($charset)

    61 	$charset = str_replace( array(',', ' '), '', strtoupper( trim($charset) ) );

    62 else

    63 	$charset = 'ASCII, UTF-8, ISO-8859-1, JIS, EUC-JP, SJIS';

    64 

    65 // No valid uses for UTF-7.

    66 if ( false !== strpos($charset, 'UTF-7') )

    67 	die;

    68 

    69 // For international trackbacks.

    70 if ( function_exists('mb_convert_encoding') ) {

    71 	$title     = mb_convert_encoding($title, get_option('blog_charset'), $charset);

    72 	$excerpt   = mb_convert_encoding($excerpt, get_option('blog_charset'), $charset);

    73 	$blog_name = mb_convert_encoding($blog_name, get_option('blog_charset'), $charset);

    74 }

    75 

    76 // Now that mb_convert_encoding() has been given a swing, we need to escape these three.

    77 $title     = wp_slash($title);

    78 $excerpt   = wp_slash($excerpt);

    79 $blog_name = wp_slash($blog_name);

    80 

    81 if ( is_single() || is_page() )

    82 	$tb_id = $posts[0]->ID;

    83 

    84 if ( !isset($tb_id) || !intval( $tb_id ) )

    85 	trackback_response(1, 'I really need an ID for this to work.');

    86 

    87 if (empty($title) && empty($tb_url) && empty($blog_name)) {

    88 	// If it doesn't look like a trackback at all.

    89 	wp_redirect(get_permalink($tb_id));

    90 	exit;

    91 }

    92 

    93 if ( !empty($tb_url) && !empty($title) ) {

    94 	header('Content-Type: text/xml; charset=' . get_option('blog_charset') );

    95 

    96 	if ( !pings_open($tb_id) )

    97 		trackback_response(1, 'Sorry, trackbacks are closed for this item.');

    98 

    99 	$title =  wp_html_excerpt( $title, 250, '…' );

   100 	$excerpt = wp_html_excerpt( $excerpt, 252, '…' );

   101 

   102 	$comment_post_ID = (int) $tb_id;

   103 	$comment_author = $blog_name;

   104 	$comment_author_email = '';

   105 	$comment_author_url = $tb_url;

   106 	$comment_content = "<strong>$title</strong>\n\n$excerpt";

   107 	$comment_type = 'trackback';

   108 

   109 	$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) );

   110 	if ( $dupe )

   111 		trackback_response(1, 'We already have a ping from that URL for this post.');

   112 

   113 	$commentdata = compact('comment_post_ID', 'comment_author', 'comment_author_email', 'comment_author_url', 'comment_content', 'comment_type');

   114 

   115 	wp_new_comment($commentdata);

   116 	$trackback_id = $wpdb->insert_id;

   117 

   118 	/**

   119 	 * Fires after a trackback is added to a post.

   120 	 *

   121 	 * @since 1.2.0

   122 	 *

   123 	 * @param int $trackback_id Trackback ID.

   124 	 */

   125 	do_action( 'trackback_post', $trackback_id );

   126 	trackback_response( 0 );

   127 }