Change to synchronous password hashing.

lib/crypto.js

@@ -39,11 +39,11 @@ export function getRandomChars(n) {
   return s;
 }
 
-export async function hashPassword(password) {
+export function hashPassword(password) {
   return bcrypt.hashSync(password, SALT_ROUNDS);
 }
 
-export async function checkPassword(password, hash) {
+export function checkPassword(password, hash) {
   return bcrypt.compareSync(password, hash);
 }