<html>
<script>
function hashPassword() {
document.getElementById("password_field").value = "hashed_value";
}
</script>
<body>
<form method="POST" target="_top" action="done.html"
onsubmit="hashPassword(); return true;" id="testform">
<input type="text" id="username_field" name="username_field">
<input type="password" id="password_field" name="password_field">
<input type="submit" id="input_submit_button" name="input_submit_button">
</form>
</body>
</html>