title: Per-host Firewalls in Symfony2
body: <p>Is it possible to map firewalls to a given host, something like this for example:</p>
  
  <pre><code>firewalls:
      dev:
          pattern: ^/(_(profiler|wdt)|css|images|js)/
          security: false
      admin:
          pattern: ^/
          host: admin.mysite.com
          http_basic:
              provider: in_memory
              realm: 'MySite Admin'
          logout: 
      main:
          pattern: ^/
          anonymous: ~
          form_login:
              provider: fos_userbundle
          ...
  </code></pre>
  
  <p>Note the fake "host" param under the admin firewall.</p>
  
  <p>The ability to limit firewalls to particular hosts would make it easy to use providers on a per-host basis.  With different domains one doesn't have to worry about overlapping patterns.</p>