Changeset 48086 for trunk/src/wp-includes/kses.php

Timestamp:

06/18/2020 08:59:43 PM (5 years ago)

Author:

adamsilverstein

Message:

Formatting: new filter safecss_filter_attr_allow_css on css parts.

Enables developers to determine whether a section of CSS should be allowed or discarded. By default, the value will be false if the part contains \ ( & } = or comments. Returning true allows the CSS part to be included in the output.

Replaces the safe_style_disallowed_chars filter introduced in r47891.

Props azaozz.
Fixes #37134.

File:

• trunk/src/wp-includes/kses.php (modified) (1 diff)

trunk/src/wp-includes/kses.php

@@ -2358 +2358 @@
 
         if ( $found ) {
+            // Check for any CSS containing \ ( & } = or comments, except for url() usage checked above.
+            $allow_css = ! preg_match( '%[\\\(&=}]|/\*%', $css_test_string );
+
             /**
-             * Filters the regex limiting the list of characters not allowed in CSS rules.
+             * Filters the check for unsafe CSS in `safecss_filter_attr`.
              *
-             * Default behaviour is to remove any CSS containing \ ( & } = or comments,
-             * except for url() usage.
+             * Enables developers to determine whether a section of CSS should be allowed or discarded.
+             * By default, the value will be false if the part contains \ ( & } = or comments.
+             * Return true to allow the CSS part to be included in the output.
              *
              * @since 5.5.0
              *
-             * @param string $regex           Regex pattern of disallowed characters in CSS rules.
-             *                                Default is '%[\\\(&=}]|/\*%'.
-             * @param string $css_test_string CSS value to test.
+             * @param bool   $allow_css       Whether the CSS in the test string is considered safe.
+             * @param string $css_test_string The css string to test.
              */
-            $disallowed_chars = apply_filters( 'safe_style_disallowed_chars', '%[\\\(&=}]|/\*%', $css_test_string );
-            if ( ! preg_match( $disallowed_chars, $css_test_string ) ) {
+            $allow_css = apply_filters( 'safecss_filter_attr_allow_css', $allow_css, $css_test_string );
+
+             // Only add the css part if it passes the regex check.
+            if ( $allow_css ) {
                 if ( '' !== $css ) {
                     $css .= ';';
                 }
+
                 $css .= $css_item;
             }