title: Relative path for JAAS keytab configuration
body: <p>I have a system wherein .NET clients authenticate against a Java server with Kerberos. Everything works, but I'm trying to improve the server configuration. Currently a <em>keytab</em> file is required in the root of <em>C:\</em> because my <em>jaas.conf</em> looks like this:</p>
  
  <pre><code>Server {
      com.sun.security.auth.module.Krb5LoginModule required
      useKeyTab=true
      storeKey=true
      isInitiator=false
      keyTab="///C:/keytab"
      principal="XXX";
  };
  </code></pre>
  
  <p>I am trying to make the <code>keyTab</code> property a relative path, but am having no luck. What I've tried:</p>
  
  <ul>
  <li><code>keyTab="///keytab"</code></li>
  <li><code>keyTab="///./keytab"</code></li>
  <li><code>keyTab="classpath:keytab"</code></li>
  </ul>
  
  <p>All of these result in an exception, so clearly the <em>keytab</em> file cannot be found.</p>
  
  <p>I've searched and <a href="http://docs.oracle.com/javase/7/docs/jre/api/security/jaas/spec/com/sun/security/auth/module/Krb5LoginModule.html" rel="noreferrer">read the docs</a> and banged my head on a wall over this. Can anyone reveal the magical incantation I need to make this happen?</p>