title: PBKDF2 security in Javascript
body: <p>In PBKDF2 the salt should be unique for each passwort, so two users using the same password are getting two different hashes.</p>
  
  <p>My Idea for the salt is a SHA1-hash of the username and the password, so it will be unique for each user.</p>
  
  <p>Actually I must generate the PBKDF2 hash in a JavaScript environment. Is it save to show how the salt is generated, because JavaScript sources are plain text?</p>