st.nextToken("=");
st.nextToken();
String iterationCount = st.nextToken(",");
// SaltedPassword := Hi(Normalize(password), salt, i)
PBKDF2Engine engine = new PBKDF2Engine(new PBKDF2Parameters("HMacSHA1", null, serverSalt, Integer.parseInt(iterationCount)));
byte[] saltedPassword = engine.deriveKey(password, 20);
// ClientKey := HMAC(SaltedPassword, "Client Key")
hmac.init(saltedPassword);
byte[] clientKey = hmac.doFinal("Client Key".getBytes());