Added more secure crypto random algorithm

Rabbit-Company · May 31, 2021 · 50039ee · 50039ee
1 parent ad5ad67
commit 50039ee
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Showing 2 changed files with 21 additions and 5 deletions.
diff --git a/js/default-functions.js b/js/default-functions.js
@@ -176,6 +176,22 @@ function isPasswordPasswordValid(password){
     return true;
 }
 
+function randRange(min, max) {
+    var range = max - min;
+    var requestBytes = Math.ceil(Math.log2(range) / 8);
+    if (!requestBytes) return min;
+
+    var maxNum = Math.pow(256, requestBytes);
+    var ar = new Uint8Array(requestBytes);
+
+    while (true) {
+        window.crypto.getRandomValues(ar);
+        var val = 0;
+        for (var i = 0;i < requestBytes;i++) val = (val << 8) + ar[i];
+        if (val < maxNum - maxNum % range) return min + (val % range);
+    }
+}
+
 function refreshPasswords(){
     var xhr = new XMLHttpRequest();
     xhr.open("POST", localStorage.url + "/?action=getPasswords");

diff --git a/js/passwords.js b/js/passwords.js
@@ -106,28 +106,28 @@ function updateGeneratedPassword(upper, number, special){
     let numbers = "1234567890";
     let specials = "!@#$%?&*";
 
-    for (let i = 0; i < length; i++) password += lowers.charAt(Math.floor(Math.random() * lowers.length));
+    for (let i = 0; i < length; i++) password += lowers.charAt(randRange(0, lowers.length));
 
     password = password.split("");
 
     if(upper){
         let upper_amount = Math.floor(length / 2 - Math.random() * (length / 2) + 1);
         for(let i = 0; i < upper_amount; i++){
-            password[Math.floor(Math.random() * password.length)] = uppers.charAt(Math.floor(Math.random() * uppers.length));
+            password[randRange(0, password.length)] = uppers.charAt(randRange(0, uppers.length));
         }
     }
 
     if(number){
         let number_amount = Math.floor(length / 2 - Math.random() * (length / 2) + 1);
         for(let i = 0; i < number_amount; i++){
-            password[Math.floor(Math.random() * password.length)] = numbers.charAt(Math.floor(Math.random() * numbers.length));
+            password[randRange(0, password.length)] = numbers.charAt(randRange(0, numbers.length));
         }
     }
 
     if(special){
-        let special_amount = Math.floor(Math.random(3) + 1);
+        let special_amount = randRange(1, 3);
         for(let i = 0; i < special_amount; i++){
-            password[Math.floor(Math.random() * password.length)] = specials.charAt(Math.floor(Math.random() * specials.length));
+            password[randRange(0, password.length)] = specials.charAt(randRange(0, specials.length));
         }
     }