From f0e32abc4fdd5dc1ff9779c18b2c217764575981 Mon Sep 17 00:00:00 2001
From: Michael Albert <michael.albert@awesome-technologies.de>
Date: Mon, 10 Feb 2020 18:07:10 +0100
Subject: [PATCH] Fix QR code creation

Change-Id: If05856a6fdafa43a93c6b57963820710db188d42
---
 src/components/ShowUserPdf.js | 22 ++++++++++------------
 1 file changed, 10 insertions(+), 12 deletions(-)

diff --git a/src/components/ShowUserPdf.js b/src/components/ShowUserPdf.js
index 321bedf..124d749 100644
--- a/src/components/ShowUserPdf.js
+++ b/src/components/ShowUserPdf.js
@@ -5,23 +5,17 @@ import { PDFExport } from "@progress/kendo-react-pdf";
 import QRCode from "qrcode.react";
 
 function xor(a, b) {
-  var res = "",
-    i = a.length,
-    j = b.length;
-  while (i-- > 0 && j-- > 0)
-    res = (parseInt(a.charAt(i)) ^ parseInt(b.charAt(j))).toString() + res;
+  var res = "";
+  for (var i = 0; i < a.length; i++) {
+    res += String.fromCharCode(a.charCodeAt(i) ^ b.charCodeAt(i % b.length));
+  }
   return res;
 }
 
 function calculateQrString(serverUrl, username, password) {
-  var magicString = "wo9k5tep252qxsa5yde7366kugy6c01w7oeeya9hrmpf0t7ii7";
-
+  const magicString = "wo9k5tep252qxsa5yde7366kugy6c01w7oeeya9hrmpf0t7ii7";
   var urlString = "user=" + username + "&password=" + password;
 
-  while (urlString.length > magicString.length) {
-    magicString += magicString;
-  }
-
   urlString = xor(urlString, magicString); // xor with magic string
   urlString = btoa(urlString); // to base64
 
@@ -86,7 +80,11 @@ const ShowUserPdf = props => {
   var qrCode = "";
   var displayname = "";
 
-  if (props.location.state) {
+  if (
+    props.location.state &&
+    props.location.state.id &&
+    props.location.state.password
+  ) {
     const { id, password } = props.location.state;
 
     const username = id.substring(1, id.indexOf(":"));