feat: adding protobuf decoder for parse of google auth migrations

lib/totp-quickjs/base32decoder.js

@@ -23,4 +23,24 @@ function leftpad(str, len, pad) {
 			(str = new Array(len + 1 - str.length).join(pad) + str),
 		str
 	);
+}
+
+export function base64decode(base64String) {    
+        var sliceSize = 1024;
+        var byteCharacters = window.atob(base64String);
+        var bytesLength = byteCharacters.length;
+        var slicesCount = Math.ceil(bytesLength / sliceSize);
+        var byteArrays = new Array(slicesCount);
+
+        for (var sliceIndex = 0; sliceIndex < slicesCount; ++sliceIndex) {
+            var begin = sliceIndex * sliceSize;
+            var end = Math.min(begin + sliceSize, bytesLength);
+
+            var bytes = new Array(end - begin);
+            for (var offset = begin, i = 0; offset < end; ++i, ++offset) {
+                bytes[i] = byteCharacters[offset].charCodeAt(0);
+            }
+            byteArrays[sliceIndex] = new Uint8Array(bytes);
+        }
+        return byteArrays
 }