Try to move sanitisation & links into setElementText

js/privatebin.js

@@ -43,26 +43,6 @@ jQuery.PrivateBin = function($, sjcl, Base64, RawDeflate) {
     var Helper = (function () {
         var me = {};
 
-        /**
-         * character to HTML entity lookup table
-         *
-         * @see    {@link https://github.com/janl/mustache.js/blob/master/mustache.js#L60}
-         * @name Helper.entityMap
-         * @private
-         * @enum   {Object}
-         * @readonly
-         */
-        var entityMap = {
-            '&': '&',
-            '<': '&lt;',
-            '>': '&gt;',
-            '"': '&quot;',
-            "'": '&#39;',
-            '/': '&#x2F;',
-            '`': '&#x60;',
-            '=': '&#x3D;'
-        };
-
         /**
          * cache for script location
          *
@@ -72,6 +52,36 @@ jQuery.PrivateBin = function($, sjcl, Base64, RawDeflate) {
          */
         var baseUri = null;
 
+        /**
+         * convert URLs to clickable links.
+         * URLs to handle:
+         * <pre>
+         *     magnet:?xt.1=urn:sha1:YNCKHTQCWBTRNJIV4WNAE52SJUQCZO5C&xt.2=urn:sha1:TXGCZQTH26NL6OUQAJJPFALHG2LTGBC7
+         *     http://example.com:8800/zero/?6f09182b8ea51997#WtLEUO5Epj9UHAV9JFs+6pUQZp13TuspAUjnF+iM+dM=
+         *     http://user:example.com@localhost:8800/zero/?6f09182b8ea51997#WtLEUO5Epj9UHAV9JFs+6pUQZp13TuspAUjnF+iM+dM=
+         * </pre>
+         * Attention: Does *not* sanitize HTML code! It is strongly advised to sanitize it after running this function.
+         *
+         *
+         * @name   Helper.urls2links
+         * @function
+         * @param  {String} html - HTML code
+         */
+        urls2links = function(html)
+        {
+            var markup = '<a href="$1" rel="nofollow">$1</a>';
+            // short test: https://regex101.com/r/AttfVd/1
+            html.replace(
+                /((http|https|ftp):\/\/[\w?=&.\/-;#@~%+*-]+(?![\w\s?&.\/;#~%"=-]*>))/ig,
+                markup
+            )
+            // shorttest: https://regex101.com/r/sCm8Xe/2
+            html.replace(
+                /((magnet):[\w?=&.\/-;#@~%+*-]+)/ig,
+                markup
+            );
+        }
+
         /**
          * converts a duration (in seconds) into human friendly approximation
          *
@@ -135,55 +145,38 @@ jQuery.PrivateBin = function($, sjcl, Base64, RawDeflate) {
         }
 
         /**
-         * set text of a jQuery element (required for IE),
+         * set text of a jQuery element (required for IE)
          *
          * @name   Helper.setElementText
          * @function
          * @param  {jQuery} $element - a jQuery element
          * @param  {string} text - the text to enter
+         * @param  {bool} convertLinks - whether to convert the links in the text
          */
-        me.setElementText = function($element, text)
+        me.setElementText = function($element, text, convertLinks)
         {
-            // For IE<10: Doesn't support white-space:pre-wrap; so we have to do this...
-            if ($('#oldienotice').is(':visible')) {
-                var html = me.htmlEntities(text).replace(/\n/ig, '\r\n<br>');
-                $element.html('<pre>' + html + '</pre>');
+            var isIe = $('#oldienotice').is(':visible');
+            // text-only and no IE -> fast way: set text-only
+            if ((convertLinks === false) && isIe === false) {
+                return $element.text(text);
             }
-            // for other (sane) browsers:
-            else
-            {
-                $element.text(text);
+
+            // convert text to plain-text
+            // but as we need to handle HTML code afterwards
+            var html = $(text).text();
+
+            if (convertLinks === true) {
+                html = me.urls2links(html);
             }
-        }
 
-        /**
-         * convert URLs to clickable links.
-         * URLs to handle:
-         * <pre>
-         *     magnet:?xt.1=urn:sha1:YNCKHTQCWBTRNJIV4WNAE52SJUQCZO5C&xt.2=urn:sha1:TXGCZQTH26NL6OUQAJJPFALHG2LTGBC7
-         *     http://example.com:8800/zero/?6f09182b8ea51997#WtLEUO5Epj9UHAV9JFs+6pUQZp13TuspAUjnF+iM+dM=
-         *     http://user:example.com@localhost:8800/zero/?6f09182b8ea51997#WtLEUO5Epj9UHAV9JFs+6pUQZp13TuspAUjnF+iM+dM=
-         * </pre>
-         *
-         * @name   Helper.urls2links
-         * @function
-         * @param  {Object} $element - a jQuery DOM element
-         */
-        me.urls2links = function($element)
-        {
-            var markup = '<a href="$1" rel="nofollow">$1</a>';
-            $element.html(
-                $element.html().replace(
-                    /((http|https|ftp):\/\/[\w?=&.\/-;#@~%+*-]+(?![\w\s?&.\/;#~%"=-]*>))/ig,
-                    markup
-                )
-            );
-            $element.html(
-                $element.html().replace(
-                    /((magnet):[\w?=&.\/-;#@~%+*-]+)/ig,
-                    markup
-                )
-            );
+            // workaround: IE<10 doesn't support white-space:pre-wrap; so we have to do this...
+            if (isIe) {
+                html = html.replace(/\n/ig, '\r\n<br>');
+            }
+
+            // finally sanitize it for security (XSS) reasons
+            html = me.sanitizeHtml(text);
+            $element.html(html);
         }
 
         /**
@@ -270,19 +263,17 @@ jQuery.PrivateBin = function($, sjcl, Base64, RawDeflate) {
         }
 
         /**
-         * convert all applicable characters to HTML entities
+         * sanitizes html code to prevent XSS attacks
          *
-         * @see    {@link https://www.owasp.org/index.php/XSS_(Cross_Site_Scripting)_Prevention_Cheat_Sheet#RULE_.231_-_HTML_Escape_Before_Inserting_Untrusted_Data_into_HTML_Element_Content}
-         * @name   Helper.htmlEntities
+         * Now uses DOMPurify instead of some self-made stuff for security reasons.
+         *
+         * @name   Helper.sanitizeHtml
          * @function
          * @param  {string} str
          * @return {string} escaped HTML
          */
-        me.htmlEntities = function(str) {
-            return String(str).replace(
-                /[&<>"'`=\/]/g, function(s) {
-                    return entityMap[s];
-                });
+        me.sanitizeHtml = function(str) {
+            return DOMPurify.sanitize(str, {SAFE_FOR_JQUERY: true});
         }
 
         /**
@@ -1766,9 +1757,8 @@ jQuery.PrivateBin = function($, sjcl, Base64, RawDeflate) {
             }
 
             // set text
-            var sanitizedText = DOMPurify.sanitize(text, {SAFE_FOR_JQUERY: true})
-            Helper.setElementText($plainText, sanitizedText);
-            Helper.setElementText($prettyPrint, sanitizedText);
+            Helper.setElementText($plainText, text, false);
+            Helper.setElementText($prettyPrint, text, true);
 
             switch (format) {
                 case 'markdown':
@@ -1793,15 +1783,12 @@ jQuery.PrivateBin = function($, sjcl, Base64, RawDeflate) {
 
                     $prettyPrint.html(
                         prettyPrintOne(
-                            Helper.htmlEntities(sanitizedText), null, true
+                            Helper.sanitizeHtml(text), null, true
                         )
                     );
                     // fall through, as the rest is the same
                 default: // = 'plaintext'
-                    // convert URLs to clickable links
-                    Helper.urls2links($plainText);
-                    Helper.urls2links($prettyPrint);
-
+                    // adjust CSS so it looks good
                     $prettyPrint.css('white-space', 'pre-wrap');
                     $prettyPrint.css('word-break', 'normal');
                     $prettyPrint.removeClass('prettyprint');
@@ -2594,7 +2581,7 @@ jQuery.PrivateBin = function($, sjcl, Base64, RawDeflate) {
             for (var i = 0; i < $head.length; i++) {
                 newDoc.write($head[i].outerHTML);
             }
-            newDoc.write('</head><body><pre>' + Helper.htmlEntities(paste) + '</pre></body></html>');
+            newDoc.write('</head><body><pre>' + Helper.sanitizeHtml(paste) + '</pre></body></html>');
             newDoc.close();
         }
 

js/test.js

@@ -93,7 +93,7 @@ describe('Helper', function () {
                 var html = '',
                     result = true;
                 ids.forEach(function(item, i) {
-                    html += '<div id="' + item.join('') + '">' + $.PrivateBin.Helper.htmlEntities(contents[i] || contents[0]) + '</div>';
+                    html += '<div id="' + item.join('') + '">' + $.PrivateBin.Helper.sanitizeHtml(contents[i] || contents[0]) + '</div>';
                 });
                 var clean = jsdom(html);
                 ids.forEach(function(item, i) {
@@ -122,7 +122,7 @@ describe('Helper', function () {
                 var html = '',
                     result = true;
                 ids.forEach(function(item, i) {
-                    html += '<div id="' + item.join('') + '">' + $.PrivateBin.Helper.htmlEntities(contents[i] || contents[0]) + '</div>';
+                    html += '<div id="' + item.join('') + '">' + $.PrivateBin.Helper.sanitizeHtml(contents[i] || contents[0]) + '</div>';
                 });
                 var elements = $('<body />').html(html);
                 ids.forEach(function(item, i) {
@@ -163,9 +163,9 @@ describe('Helper', function () {
                 var query = query.join(''),
                     fragment = fragment.join(''),
                     url = schema + '://' + address.join('') + '/?' + query + '#' + fragment,
-                    prefix = $.PrivateBin.Helper.htmlEntities(prefix),
-                    postfix = ' ' + $.PrivateBin.Helper.htmlEntities(postfix),
-                    element = $('<div>' + prefix + url + postfix + '</div>');
+                    prefix = $.PrivateBin.Helper.sanitizeHtml(prefix),
+                    postfix = ' ' + $.PrivateBin.Helper.sanitizeHtml(postfix),
+                    element = '<div>' + prefix + url + postfix + '</div>';
 
                 // special cases: When the query string and fragment imply the beginning of an HTML entity, eg. &#0 or &#x
                 if (
@@ -175,11 +175,11 @@ describe('Helper', function () {
                 {
                     url = schema + '://' + address.join('') + '/?' + query.substring(0, query.length - 1);
                     postfix = '';
-                    element = $('<div>' + prefix + url + '</div>');
+                    element = '<div>' + prefix + url + '</div>';
                 }
 
                 $.PrivateBin.Helper.urls2links(element);
-                return element.html() === $('<div>' + prefix + '<a href="' + url + '" rel="nofollow">' + url + '</a>' + postfix + '</div>').html();
+                return element.html() === '<div>' + prefix + '<a href="' + url + '" rel="nofollow">' + url + '</a>' + postfix + '</div>';
             }
         );
         jsc.property(
@@ -189,8 +189,8 @@ describe('Helper', function () {
             'string',
             function (prefix, query, postfix) {
                 var url = 'magnet:?' + query.join('').replace(/^&+|&+$/gm,''),
-                    prefix = $.PrivateBin.Helper.htmlEntities(prefix),
-                    postfix = $.PrivateBin.Helper.htmlEntities(postfix),
+                    prefix = $.PrivateBin.Helper.sanitizeHtml(prefix),
+                    postfix = $.PrivateBin.Helper.sanitizeHtml(postfix),
                     element = $('<div>' + prefix + url + ' ' + postfix + '</div>');
                 $.PrivateBin.Helper.urls2links(element);
                 return element.html() === $('<div>' + prefix + '<a href="' + url + '" rel="nofollow">' + url + '</a> ' + postfix + '</div>').html();
@@ -329,7 +329,7 @@ describe('Helper', function () {
         );
     });
 
-    describe('htmlEntities', function () {
+    describe('sanitizeHtml', function () {
         after(function () {
             cleanup();
         });
@@ -338,7 +338,7 @@ describe('Helper', function () {
             'removes all HTML entities from any given string',
             'string',
             function (string) {
-                var result = $.PrivateBin.Helper.htmlEntities(string);
+                var result = $.PrivateBin.Helper.sanitizeHtml(string);
                 return !(/[<>"'`=\/]/.test(result)) && !(string.indexOf('&') > -1 && !(/&amp;/.test(result)));
             }
         );
@@ -583,8 +583,8 @@ describe('Model', function () {
             'string',
             'small nat',
             function (keys, value, key) {
-                keys = keys.map($.PrivateBin.Helper.htmlEntities);
-                value = $.PrivateBin.Helper.htmlEntities(value);
+                keys = keys.map($.PrivateBin.Helper.sanitizeHtml);
+                value = $.PrivateBin.Helper.sanitizeHtml(value);
                 var content = keys.length > key ? keys[key] : (keys.length > 0 ? keys[0] : 'null'),
                     contents = '<select id="pasteExpiration" name="pasteExpiration">';
                 keys.forEach(function(item) {
@@ -596,7 +596,7 @@ describe('Model', function () {
                 });
                 contents += '</select>';
                 $('body').html(contents);
-                var result = $.PrivateBin.Helper.htmlEntities(
+                var result = $.PrivateBin.Helper.sanitizeHtml(
                     $.PrivateBin.Model.getExpirationDefault()
                 );
                 $.PrivateBin.Model.reset();
@@ -617,8 +617,8 @@ describe('Model', function () {
             'string',
             'small nat',
             function (keys, value, key) {
-                keys = keys.map($.PrivateBin.Helper.htmlEntities);
-                value = $.PrivateBin.Helper.htmlEntities(value);
+                keys = keys.map($.PrivateBin.Helper.sanitizeHtml);
+                value = $.PrivateBin.Helper.sanitizeHtml(value);
                 var content = keys.length > key ? keys[key] : (keys.length > 0 ? keys[0] : 'null'),
                     contents = '<select id="pasteFormatter" name="pasteFormatter">';
                 keys.forEach(function(item) {
@@ -630,7 +630,7 @@ describe('Model', function () {
                 });
                 contents += '</select>';
                 $('body').html(contents);
-                var result = $.PrivateBin.Helper.htmlEntities(
+                var result = $.PrivateBin.Helper.sanitizeHtml(
                     $.PrivateBin.Model.getFormatDefault()
                 );
                 $.PrivateBin.Model.reset();
@@ -649,7 +649,7 @@ describe('Model', function () {
             'checks if the element with id "cipherdata" contains any data',
             'asciistring',
             function (value) {
-                value = $.PrivateBin.Helper.htmlEntities(value).trim();
+                value = $.PrivateBin.Helper.sanitizeHtml(value).trim();
                 $('body').html('<div id="cipherdata">' + value + '</div>');
                 $.PrivateBin.Model.init();
                 var result = $.PrivateBin.Model.hasCipherData();
@@ -669,10 +669,10 @@ describe('Model', function () {
             'returns the contents of the element with id "cipherdata"',
             'asciistring',
             function (value) {
-                value = $.PrivateBin.Helper.htmlEntities(value).trim();
+                value = $.PrivateBin.Helper.sanitizeHtml(value).trim();
                 $('body').html('<div id="cipherdata">' + value + '</div>');
                 $.PrivateBin.Model.init();
-                var result = $.PrivateBin.Helper.htmlEntities(
+                var result = $.PrivateBin.Helper.sanitizeHtml(
                     $.PrivateBin.Model.getCipherData()
                 );
                 $.PrivateBin.Model.reset();