chore: Experimentally removing the depth counter logic as we have bet…

…ter defenses now

dist/purify.es.mjs

@@ -48,10 +48,6 @@ const stringTrim = unapply(String.prototype.trim);
 const objectHasOwnProperty = unapply(Object.prototype.hasOwnProperty);
 const regExpTest = unapply(RegExp.prototype.test);
 const typeErrorCreate = unconstruct(TypeError);
-function numberIsNaN(x) {
-  // eslint-disable-next-line unicorn/prefer-number-properties
-  return typeof x === 'number' && isNaN(x);
-}
 
 /**
  * Creates a new function that calls the given function with a specified thisArg and arguments.
@@ -537,9 +533,6 @@ function createDOMPurify() {
   /* Keep a reference to config to pass to hooks */
   let CONFIG = null;
 
-  /* Specify the maximum element nesting depth to prevent mXSS */
-  const MAX_NESTING_DEPTH = 255;
-
   /* Ideally, do not touch anything below this line */
   /* ______________________________________________ */
 
@@ -950,11 +943,7 @@ function createDOMPurify() {
    * @return {Boolean} true if clobbered, false if safe
    */
   const _isClobbered = function _isClobbered(elm) {
-    return elm instanceof HTMLFormElement && (
-    // eslint-disable-next-line unicorn/no-typeof-undefined
-    typeof elm.__depth !== 'undefined' && typeof elm.__depth !== 'number' ||
-    // eslint-disable-next-line unicorn/no-typeof-undefined
-    typeof elm.__removalCount !== 'undefined' && typeof elm.__removalCount !== 'number' || typeof elm.nodeName !== 'string' || typeof elm.textContent !== 'string' || typeof elm.removeChild !== 'function' || !(elm.attributes instanceof NamedNodeMap) || typeof elm.removeAttribute !== 'function' || typeof elm.setAttribute !== 'function' || typeof elm.namespaceURI !== 'string' || typeof elm.insertBefore !== 'function' || typeof elm.hasChildNodes !== 'function');
+    return elm instanceof HTMLFormElement && (typeof elm.nodeName !== 'string' || typeof elm.textContent !== 'string' || typeof elm.removeChild !== 'function' || !(elm.attributes instanceof NamedNodeMap) || typeof elm.removeAttribute !== 'function' || typeof elm.setAttribute !== 'function' || typeof elm.namespaceURI !== 'string' || typeof elm.insertBefore !== 'function' || typeof elm.hasChildNodes !== 'function');
   };
 
   /**
@@ -1105,7 +1094,7 @@ function createDOMPurify() {
   // eslint-disable-next-line complexity
   const _isValidAttribute = function _isValidAttribute(lcTag, lcName, value) {
     /* Make sure attribute cannot clobber */
-    if (SANITIZE_DOM && (lcName === 'id' || lcName === 'name') && (value in document || value in formElement || value === '__depth' || value === '__removalCount')) {
+    if (SANITIZE_DOM && (lcName === 'id' || lcName === 'name') && (value in document || value in formElement)) {
       return false;
     }
 
@@ -1296,32 +1285,9 @@ function createDOMPurify() {
       if (_sanitizeElements(shadowNode)) {
         continue;
       }
-      const parentNode = getParentNode(shadowNode);
-
-      /* Set the nesting depth of an element */
-      if (shadowNode.nodeType === NODE_TYPE.element) {
-        if (parentNode && parentNode.__depth) {
-          /*
-            We want the depth of the node in the original tree, which can
-            change when it's removed from its parent.
-          */
-          shadowNode.__depth = (shadowNode.__removalCount || 0) + parentNode.__depth + 1;
-        } else {
-          shadowNode.__depth = 1;
-        }
-      }
-
-      /*
-       * Remove an element if nested too deeply to avoid mXSS
-       * or if the __depth might have been tampered with
-       */
-      if (shadowNode.__depth >= MAX_NESTING_DEPTH || shadowNode.__depth < 0 || numberIsNaN(shadowNode.__depth)) {
-        _forceRemove(shadowNode);
-      }
 
       /* Deep shadow DOM detected */
       if (shadowNode.content instanceof DocumentFragment) {
-        shadowNode.content.__depth = shadowNode.__depth;
         _sanitizeShadowDOM(shadowNode.content);
       }
 
@@ -1437,32 +1403,9 @@ function createDOMPurify() {
       if (_sanitizeElements(currentNode)) {
         continue;
       }
-      const parentNode = getParentNode(currentNode);
-
-      /* Set the nesting depth of an element */
-      if (currentNode.nodeType === NODE_TYPE.element) {
-        if (parentNode && parentNode.__depth) {
-          /*
-            We want the depth of the node in the original tree, which can
-            change when it's removed from its parent.
-          */
-          currentNode.__depth = (currentNode.__removalCount || 0) + parentNode.__depth + 1;
-        } else {
-          currentNode.__depth = 1;
-        }
-      }
-
-      /*
-       * Remove an element if nested too deeply to avoid mXSS
-       * or if the __depth might have been tampered with
-       */
-      if (currentNode.__depth >= MAX_NESTING_DEPTH || currentNode.__depth < 0 || numberIsNaN(currentNode.__depth)) {
-        _forceRemove(currentNode);
-      }
 
       /* Shadow DOM detected, sanitize it */
       if (currentNode.content instanceof DocumentFragment) {
-        currentNode.content.__depth = currentNode.__depth;
         _sanitizeShadowDOM(currentNode.content);
       }