Merge pull request from GHSA-cxjc-r2fp-7mq6

* Add config option `allowUnsafeHtml`: default is `false` which results in
  `<` being replaced with `&lt;`
* Add config option `linkFilter`: can be a function or array of filter pairs
  to control exactly what filtering is applied

This update should minimally affect production applications:

* The behavior of existing links with HTML content will be unchanged
* Existing links that are edited and saved will be filtered (this is only if
  the link is edited, other content within the editor can be edited without
  affecting the link)
* Newly created links will be filtered by default
* For production code to continue working as-is with new data the application
  code will have to be updated to specify `true` for the `LinkDialog` plugin's
  `allowUnsafeHtml` option
(cherry picked from commit 7d9d492)

_editor/plugins/LinkDialog.js

@@ -1,5 +1,6 @@
 define([
 	"require",
+	"dojo/_base/array",
 	"dojo/_base/declare", // declare
 	"dojo/dom-attr", // domAttr.get
 	"dojo/keys", // keys.ENTER
@@ -11,7 +12,7 @@ define([
 	"../_Plugin",
 	"../../form/DropDownButton",
 	"../range"
-], function(require, declare, domAttr, keys, lang, on, has, query, string,
+], function(require, array, declare, domAttr, keys, lang, on, has, query, string,
 	_Plugin, DropDownButton, rangeapi){
 
 	// module:
@@ -26,6 +27,21 @@ define([
 		//
 		//		- createLink
 
+		// allowUnsafeHtml: boolean
+		//		If false (default), the link description will be filtered to prevent HTML content.
+		//		If true no filtering is done, allowing for HTML content within the link element.
+		//		The filter can be specified with the 'linkFilter' option.
+		allowUnsafeHtml: false,
+
+		// linkFilter: function or array of replacement pairs
+		//		If 'allowUnsafeHtml' is false then this filter will be applied to the link Description value.
+		//		function: the function will be invoked with the string value of the Description field and its
+		//			return value will be used
+		//		array: each array item should be an array of two values to pass to String#replace
+		linkFilter: [
+			[/</g, "&lt;"]
+		],
+
 		// Override _Plugin.buttonClass.   This plugin is controlled by a DropDownButton
 		// (which triggers a TooltipDialog).
 		buttonClass: DropDownButton,
@@ -252,6 +268,16 @@ define([
 			if(args && args.urlInput){
 				args.urlInput = args.urlInput.replace(/"/g, "&quot;");
 			}
+			if(!this.allowUnsafeHtml && args && args.textInput){
+				if(typeof this.linkFilter === 'function'){
+					args.textInput = this.linkFilter(args.textInput);
+				}
+				else{
+					array.forEach(this.linkFilter, function (currentFilter) {
+						args.textInput = args.textInput.replace(currentFilter[0], currentFilter[1]);
+					});
+				}
+			}
 			return args;
 		},
 
@@ -629,8 +655,15 @@ define([
 	});
 
 	// Register these plugins
-	_Plugin.registry["createLink"] = function(){
-		return new LinkDialog({command: "createLink"});
+	_Plugin.registry["createLink"] = function(args){
+		var pluginOptions = {
+			command: "createLink",
+			allowUnsafeHtml: ("allowUnsafeHtml" in args) ? args.allowUnsafeHtml : false
+		};
+		if("linkFilter" in args){
+			pluginOptions.linkFilter = args.linkFilter;
+		}
+		return new LinkDialog(pluginOptions);
 	};
 	_Plugin.registry["insertImage"] = function(){
 		return new ImgLinkDialog({command: "insertImage"});

tests/editor/test_LinkDialog.html

@@ -7,6 +7,10 @@
 	<script type="text/javascript" src="../boilerplate.js"></script>
 
 	<script type="text/javascript">
+		function filterLink () {
+			return 'Filtered Value';
+		}
+
 		require([
 			"dojo/parser",
 			"dijit/Editor",
@@ -36,6 +40,22 @@
 		</div>
 	</div>
 
+	<p>Editor with <code>allowUnsafeHtml</code> set to <code>true</code></p>
+	<div style="border: 1px dotted black;">
+		<div id="editorUnsafe" data-dojo-type="dijit/Editor" data-dojo-props='"aria-label":"editor",extraPlugins:[{name: "createLink", allowUnsafeHtml: true}, "insertImage", "viewSource"]'>
+			<p>This editor will allow unrestricted HTML in the Description field of links</p>
+			<br>
+		</div>
+	</div>
+
+	<p>Editor with custom <code>linkFilter</code> function</p>
+	<div style="border: 1px dotted black;">
+		<div id="editorLinkFilter" data-dojo-type="dijit/Editor" data-dojo-props='"aria-label":"editor",extraPlugins:[{name: "createLink", linkFilter: filterLink}, "insertImage", "viewSource"]'>
+			<p>Links created in this editor will always have a description of "Filtered Value", which is the value returned by the custom <code>linkFilter</code> function.</p>
+			<br>
+		</div>
+	</div>
+
 	<p>RTL Editor:</p>
 	<div style="border: 1px dotted black;">
 		<div id="reditor" data-dojo-type="dijit/Editor" dir="rtl" data-dojo-props='"aria-label":"reditor",extraPlugins:["createLink", "insertImage"]'>