/**
* Some functions to help implement an external link filter for spam control.
*
- * TODO: implement the filter. Currently these are just some functions to help
+ * @todo implement the filter. Currently these are just some functions to help
* maintenance/cleanupSpam.php remove links to a single specified domain. The
* next thing is to implement functions for checking a given page against a big
* list of domains.
* Another cool thing to do would be a web interface for fast spam removal.
*/
class LinkFilter {
+
/**
- * @static
+ * Check whether $text contains a link to $filterEntry
+ *
+ * @param $text String: text to check
+ * @param $filterEntry String: domainparts, see makeRegex() for more details
+ * @return Integer: 0 if no match or 1 if there's at least one match
*/
- function matchEntry( $text, $filterEntry ) {
+ static function matchEntry( $text, $filterEntry ) {
$regex = LinkFilter::makeRegex( $filterEntry );
return preg_match( $regex, $text );
}
/**
- * @static
+ * Builds a regex pattern for $filterEntry.
+ *
+ * @param $filterEntry String: URL, if it begins with "*.", it'll be
+ * replaced to match any subdomain
+ * @return String: regex pattern, for preg_match()
*/
- function makeRegex( $filterEntry ) {
+ private static function makeRegex( $filterEntry ) {
$regex = '!http://';
if ( substr( $filterEntry, 0, 2 ) == '*.' ) {
- $regex .= '([A-Za-z0-9.-]+\.|)';
+ $regex .= '(?:[A-Za-z0-9.-]+\.|)';
$filterEntry = substr( $filterEntry, 2 );
}
$regex .= preg_quote( $filterEntry, '!' ) . '!Si';
*
* Asterisks in any other location are considered invalid.
*
- * @static
* @param $filterEntry String: domainparts
* @param $prot String: protocol
+ * @return String
+ * @deprecated Use makeLikeArray() and pass result to Database::buildLike() instead
+ */
+ public static function makeLike( $filterEntry , $prot = 'http://' ) {
+ wfDeprecated( __METHOD__ );
+
+ $like = self::makeLikeArray( $filterEntry , $prot );
+ if ( !$like ) {
+ return false;
+ }
+ $dbw = wfGetDB( DB_MASTER );
+ $s = $dbw->buildLike( $like );
+ $m = false;
+ if ( preg_match( "/^ *LIKE '(.*)' *$/", $s, $m ) ) {
+ return $m[1];
+ } else {
+ throw new MWException( __METHOD__.': this DBMS is not supported by this function.' );
+ }
+ }
+
+ /**
+ * Make an array to be used for calls to DatabaseBase::buildLike(), which
+ * will match the specified string. There are several kinds of filter entry:
+ * *.domain.com - Produces http://com.domain.%, matches domain.com
+ * and www.domain.com
+ * domain.com - Produces http://com.domain./%, matches domain.com
+ * or domain.com/ but not www.domain.com
+ * *.domain.com/x - Produces http://com.domain.%/x%, matches
+ * www.domain.com/xy
+ * domain.com/x - Produces http://com.domain./x%, matches
+ * domain.com/xy but not www.domain.com/xy
+ *
+ * Asterisks in any other location are considered invalid.
+ *
+ * @param $filterEntry String: domainparts
+ * @param $prot String: protocol
+ * @return Array to be passed to DatabaseBase::buildLike() or false on error
*/
- function makeLike( $filterEntry , $prot = 'http' ) {
+ public static function makeLikeArray( $filterEntry , $prot = 'http://' ) {
+ $db = wfGetDB( DB_MASTER );
if ( substr( $filterEntry, 0, 2 ) == '*.' ) {
$subdomains = true;
$filterEntry = substr( $filterEntry, 2 );
$path = '/';
$host = $filterEntry;
}
- $host = strtolower( implode( '.', array_reverse( explode( '.', $host ) ) ) );
- if ( substr( $host, -1, 1 ) !== '.' ) {
- $host .= '.';
+ // Reverse the labels in the hostname, convert to lower case
+ // For emails reverse domainpart only
+ if ( $prot == 'mailto:' && strpos($host, '@') ) {
+ // complete email adress
+ $mailparts = explode( '@', $host );
+ $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
+ $host = $domainpart . '@' . $mailparts[0];
+ $like = array( "$prot$host", $db->anyString() );
+ } elseif ( $prot == 'mailto:' ) {
+ // domainpart of email adress only. do not add '.'
+ $host = strtolower( implode( '.', array_reverse( explode( '.', $host ) ) ) );
+ $like = array( "$prot$host", $db->anyString() );
+ } else {
+ $host = strtolower( implode( '.', array_reverse( explode( '.', $host ) ) ) );
+ if ( substr( $host, -1, 1 ) !== '.' ) {
+ $host .= '.';
+ }
+ $like = array( "$prot$host" );
+
+ if ( $subdomains ) {
+ $like[] = $db->anyString();
+ }
+ if ( !$subdomains || $path !== '/' ) {
+ $like[] = $path;
+ $like[] = $db->anyString();
+ }
}
- $like = "$prot://$host";
-
- if ( $subdomains ) {
- $like .= '%';
+ return $like;
+ }
+
+ /**
+ * Filters an array returned by makeLikeArray(), removing everything past first pattern placeholder.
+ *
+ * @param $arr array: array to filter
+ * @return filtered array
+ */
+ public static function keepOneWildcard( $arr ) {
+ if( !is_array( $arr ) ) {
+ return $arr;
}
- if ( !$subdomains || $path !== '/' ) {
- $like .= $path . '%';
+
+ foreach( $arr as $key => $value ) {
+ if ( $value instanceof LikeMatch ) {
+ return array_slice( $arr, 0, $key + 1 );
+ }
}
- return $like;
+
+ return $arr;
}
}
-?>