title: Spring security csrf is null
body: <p>I have login form and I want to protect it against csrf atacks.</p>
  
  <p>My spring-security.xml</p>
  
  <pre><code>&lt;sec:http auto-config="true" use-expressions="true"&gt;
      ...
      &lt;sec:csrf /&gt;
  &lt;/sec:http&gt;
  </code></pre>
  
  <p>My jsp-file (use tiles):</p>
  
  <pre><code>&lt;form class="navbar-form navbar-right form-inline" method="POST" role="form"
    action="j_spring_security_check"&gt;
    &lt;div class="form-group"&gt;
      &lt;input class="form-control" type="email" name="j_username"&gt;
    &lt;/div&gt;
    &lt;div class="form-group"&gt;
      &lt;input class="form-control" type="password" name="j_password"&gt;
    &lt;/div&gt;
    &lt;button class="btn btn-default" type="submit"&gt;Login&lt;/button&gt;
  
    &lt;input type="hidden" name="${_csrf.parameterName}" value="${_csrf.token}"&gt;
  &lt;/form&gt;
  </code></pre>
  
  <p>I can authorize, but csrf is empty:</p>
  
  <pre><code>&lt;input type="hidden" value="" name=""&gt;
  </code></pre>
  
  <p>Can anyone help me?</p>