JNDI (using a java servlet)

[Joseph]

I have a servlet that authenticates a user against LDAP.  The servlet
runs perfect as an application, but causes an error when I convert it
to a servlet.
The problem seems to have something to do with DirContex because if I
comment it out, I get no error.

Code snip:

import java.util.Hashtable;
import java.util.Enumeration;
import javax.naming.*;
import javax.naming.directory.*;
import javax.servlet.http.*;
import javax.servlet.*;
import java.io.*;
       .
       .
       .
public void doGet(HttpServletRequest req, HttpServletResponse res)
throws
                                                ServletException, IOException
{
   // Set content type and create a stream for output
   res.setContentType("text/html");
   PrintWriter out = res.getWriter();

   // Get an Authorization header
   String auth = req.getHeader("Authorization");

   try
   {
      Hashtable env = new Hashtable();
      env.put(Context.INITIAL_CONTEXT_FACTORY, INITCTX);
      env.put(Context.PROVIDER_URL, MY_HOST);
           
      /* 
      * Error occurs here.  
      * If I comment this out -> no error
      */
      DirContext ctx = new InitialDirContext(env);
           
      SearchControls constraints = new SearchControls();
      constraints.setSearchScope(SearchControls.SUBTREE_SCOPE);

      NamingEnumeration results = ctx.search(MY_SEARCHBASE, MY_FILTER,
constraints);

      while ( results != null && results.hasMore() )
      {
         SearchResult sr = (SearchResult)results.next();
         Attributes attrs = sr.getAttributes();

         for ( NamingEnumeration ne = attrs.getAll(); ne.hasMoreElements() ;
)
         {
            Attribute attr = (Attribute)ne.next();
            String attrID = attr.getID();
            out.println( attrID + ":");

            for ( Enumeration vals = attr.getAll(); vals.hasMoreElements() ;
)
            {
               out.println( "\t" + vals.nextElement() );
            }
          }
          out.println( "\n" );
      }
   }
   catch( Exception e )
   {
      out.println("Error in Try Method");
      e.printStackTrace();
      System.exit(1);
   }

   // Check if user exists in the LDAP database
   if (!allowedUser(auth))
   {
      // Not allowed, so display unauthorized message
      out.println("NOT AUTHORIZED!!");
      res.sendError(res.SC_UNAUTHORIZED);
      res.setHeader("WWW-Authenticate", "BASIC realm=\"users\"");
   }
   else
   {
      // User has a valid entry in the database
      out.println("<H1>You have been authorized!!...</H1>");
   }

}  // end doGet


The error I get in the browser is:

Error in Try Method 

Error: 500
Location: /servlet/TestLdap
Internal Servlet Error:

java.security.AccessControlException: access denied
(java.lang.RuntimePermission exitVM)
        at 
java.security.AccessControlContext.checkPermission(AccessControlContext.java:272)
        at java.security.AccessController.checkPermission(AccessController.java:399)
        at java.lang.SecurityManager.checkPermission(SecurityManager.java:545)
        at java.lang.SecurityManager.checkExit(SecurityManager.java:765)
        at java.lang.Runtime.exit(Runtime.java:91)
        at java.lang.System.exit(System.java:701)
        at TestLdap.doGet(TestLdap.java:91)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:740)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
        at org.apache.tomcat.core.ServletWrapper.doService(ServletWrapper.java:405)
        at org.apache.tomcat.core.Handler.service(Handler.java:287)
        at org.apache.tomcat.core.ServletWrapper.service(ServletWrapper.java:372)
        at 
org.apache.tomcat.core.ContextManager.internalService(ContextManager.java:812)
        at org.apache.tomcat.core.ContextManager.service(ContextManager.java:758)
        at 
org.apache.tomcat.service.connector.Ajp12ConnectionHandler.processConnection(Ajp12ConnectionHandler.java:166)
        at org.apache.tomcat.service.TcpWorkerThread.runIt(PoolTcpEndpoint.java:416)
        at org.apache.tomcat.util.ThreadPool$ControlRunnable.run(ThreadPool.java:501)
        at java.lang.Thread.run(Thread.java:484)

Notes:
I'm using Tomcat with Apache on Linux.
I have JAVA_HOME & TOMCAT_HOME set properly.
A "Hello World" servlet works fine.

Thanks in advance!
-joe