/*
 * JBoss, Home of Professional Open Source.
 * Copyright 2006, Red Hat Middleware LLC, and individual contributors
 * as indicated by the @author tags. See the copyright.txt file in the
 * distribution for a full listing of individual contributors.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */
package org.jboss.mq.security;

import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;
import javax.jms.Destination;
import javax.jms.JMSException;
import javax.jms.JMSSecurityException;
import javax.jms.InvalidDestinationException;
import javax.jms.TemporaryQueue;
import javax.jms.TemporaryTopic;
import org.jboss.mq.ConnectionToken;
import org.jboss.mq.SpyMessage;
import org.jboss.mq.SpyDestination;
import org.jboss.mq.SpyTopic;
import org.jboss.mq.DurableSubscriptionID;
import org.jboss.mq.Subscription;
import org.jboss.mq.TransactionRequest;
import org.jboss.mq.server.JMSServerInterceptorSupport;
/**
 * ServerSecurityInvoker.java
 *
 * @author <a href="mailto:pra@tim.se">Peter Antman</a>
 * @version $Revision: 57198 $
 */
public class ServerSecurityInterceptor extends JMSServerInterceptorSupport
{
   SecurityManager manager;

   /**
    * The temporary destinations for a connection
    */
   private HashMap tempDests = new HashMap();

   public ServerSecurityInterceptor(SecurityManager manager)
   {
      super();
      this.manager = manager;
   }

   public String authenticate(String name, String password) throws JMSException
   {
      log.trace("Authenticating user " + name);
      return manager.authenticate(name, password);
   }

   /**
    * Close connection. Logout user after connection is closed.
    *
    * @param dc             Description of Parameter
    * @exception JMSException  Description of Exception
    */
   public void connectionClosing(ConnectionToken dc) throws JMSException
   {
      super.connectionClosing(dc);
      manager.logout(dc);
      removeTemporaryDestinations(dc);
   }

   /*
    Here is a number of methods that I do no know if we should check access on.
    
    createQueue()
    createTopic()

    unsubscribe() - probably not.
    */
   //
   // Read methods, to check access on
   // 
   public SpyMessage[] browse(ConnectionToken dc, Destination dest, String selector) throws JMSException
   {
      if (log.isTraceEnabled())
         log.trace("Checking browse authorize on " + dc + " dest=" + dest);
      if (!authorizeRead(dc, ((SpyDestination) dest).getName()))
         throw new JMSSecurityException("Connection not authorized to browse to destination: " + dest);
      return super.browse(dc, dest, selector);
   }

   // FIXME This might actually be unneeded since a subscribe is 
   // allways done first. 
   // fuck.
   // If we remove it, remember to remove the getSubscription method
   public SpyMessage receive(ConnectionToken dc, int subscriberId, long wait) throws JMSException
   {
      if (log.isTraceEnabled())
         log.trace("Checking receive authorize on " + dc + " subId=" + subscriberId);
      // Another nightmare, how the fck do we get the dest name.
      Subscription sub = super.getSubscription(dc, subscriberId);
      String destName = sub.destination.getName();
      if (!authorizeRead(dc, destName))
         throw new JMSSecurityException("Connection not authorized to receive from destination: " + destName);
      return super.receive(dc, subscriberId, wait);
   }

   // The price we pay for adding this to an implementation not done
   // for acl's. The method to create a durable susbcriber is this, but
   // with a durableSubscriptionID in the destination of the subscription.
   // For all but, durable subscriptions this is a read access thingy.
   // Even more: if this is a create of a durable sub, or a change of one
   // or just usage of an existing one, that does basically only JMSTopic (it's new or has changed) and StateManager (its allowed) know of.
   // The logic has to be this, to not get into trouble: for ALL usage
   // of a durable sub create access is demanded!
   //
   public void subscribe(org.jboss.mq.ConnectionToken dc, org.jboss.mq.Subscription sub) throws JMSException
   {
      if (log.isTraceEnabled())
         log.trace("Checking subscribe authorize on " + dc + " sub=" + sub);
      // Do some sanity checks
      if (sub == null)
         throw new JMSException("The subscription is not allowed to be null");
      else if (sub.destination == null)
         throw new InvalidDestinationException("Destination is not allowed to be null");
      // Check if its a durable sub/ this might actually not be true create
      // only access to an old one. But we only allow read from durable
      // if you actually have the rights to create one, or...does this make
      // preconfigured clientID meaningless.
      SpyDestination dest = sub.destination;
      String destName = dest.getName();
      if (dest instanceof SpyTopic)
      {
         // Check durable sub
         DurableSubscriptionID id = ((SpyTopic) dest).getDurableSubscriptionID();
         if (id != null)
         {
            // Durable sub, check create access.
            if (!authorizeCreate(dc, destName))
               throw new JMSSecurityException("Connection not authorized to do durable subscription on topic: "
                     + destName);
         }
      }
      // We ALLWAYS check read access, even for durables
      if (!authorizeRead(dc, destName))
         throw new JMSSecurityException("Connection not authorized to subscribe to destination: " + destName);
      super.subscribe(dc, sub);
   }

   //
   // Write methods, to check access on
   //
   public void addMessage(ConnectionToken dc, SpyMessage message) throws JMSException
   {
      String dest = ((SpyDestination) message.getJMSDestination()).getName();
      if (!authorizeWrite(dc, dest))
         throw new JMSSecurityException("Connection not authorized to addMessages to destination: " + dest);
      super.addMessage(dc, message);
   }

   // Check that a transaction request is authorized to send the messages
   public void transact(ConnectionToken dc, TransactionRequest t) throws JMSException
   {
      if (t.messages != null)
      {
         // Optimization for common case
         if (t.messages.length == 1)
         {
            String dest = ((SpyDestination) t.messages[0].getJMSDestination()).getName();
            if (authorizeWrite(dc, dest) == false)
               throw new JMSSecurityException("Connection not authorized to addMessages to destination: " + dest);
         }
         else if (t.messages.length > 0)
         {
            HashSet destinations = new HashSet();
            for (int i = 0; i < t.messages.length; ++i)
               destinations.add(((SpyDestination) t.messages[i].getJMSDestination()).getName());
            
            for (Iterator i = destinations.iterator(); i.hasNext();)
            {
               String destinationName = (String) i.next();
               if (authorizeWrite(dc, destinationName) == false)
                  throw new JMSSecurityException("Connection not authorized to addMessages to destination: " + destinationName);
            }
         }
      }
      super.transact(dc, t);
   }
   
   //
   // Create methods, to check access on
   //
   public void destroySubscription(ConnectionToken dc, DurableSubscriptionID id) throws JMSException
   {
      // Oh, this fucker is a nightmare. How do we get wich topic the
      // connection is trying to unsubscribe from
      SpyTopic t = super.getDurableTopic(id);
      if (t == null)
         throw new InvalidDestinationException("No durable topic found for subscription " + id.getSubscriptionName());
      if (!authorizeCreate(dc, t.getName()))
         throw new JMSSecurityException("Connection not authorized to unsubscribe from subscription: " + t.getName());
      super.destroySubscription(dc, id);
   }

   public TemporaryTopic getTemporaryTopic(ConnectionToken dc) throws JMSException
   {
      TemporaryTopic result = super.getTemporaryTopic(dc);
      addTemporaryDestination(dc, result);
      return result;
   }

   public TemporaryQueue getTemporaryQueue(ConnectionToken dc) throws JMSException
   {
      TemporaryQueue result = super.getTemporaryQueue(dc);
      addTemporaryDestination(dc, result);
      return result;
   }

   public void deleteTemporaryDestination(ConnectionToken dc, SpyDestination destination) throws JMSException
   {
      removeTemporaryDestination(dc, destination);
      super.deleteTemporaryDestination(dc, destination);
   }

   //
   // Security helper methods
   //
   public boolean authorizeRead(ConnectionToken dc, String destination) throws JMSException
   {
      // First we must get access to the destinations security meta data
      SecurityMetadata m = manager.getSecurityMetadata(destination);
      if (m == null)
      {
         log.warn("No security configuration avaliable for " + destination);
         return false;//FIXME, is this OK?
      }
      Set readPrincipals = m.getReadPrincipals();
      if (manager.authorize(dc, readPrincipals))
         return true;
      else
         return false;
   }

   public boolean authorizeWrite(ConnectionToken dc, String destination) throws JMSException
   {
      // First we must get access to the destinations security meta data
      SecurityMetadata m = manager.getSecurityMetadata(destination);
      if (m == null)
      {
         log.warn("No security configuration avaliable for " + destination);
         return false;//FIXME, is this OK?
      }
      Set writePrincipals = m.getWritePrincipals();
      if (manager.authorize(dc, writePrincipals))
         return true;
      else
         return false;
   }

   public boolean authorizeCreate(ConnectionToken dc, String destination) throws JMSException
   {
      // First we must get access to the destinations security meta data
      SecurityMetadata m = manager.getSecurityMetadata(destination);
      if (m == null)
      {
         log.warn("No security configuration avaliable for " + destination);
         return false;//FIXME, is this OK?
      }
      Set createPrincipals = m.getCreatePrincipals();
      if (manager.authorize(dc, createPrincipals))
         return true;
      else
         return false;
   }

   /**
    * Remember the temporary destinations for a connection
    */
   public void addTemporaryDestination(ConnectionToken dc, Destination destination)
   {
      synchronized (tempDests)
      {
         HashSet set = (HashSet) tempDests.get(dc);
         if (set == null)
         {
            set = new HashSet();
            tempDests.put(dc, set);
         }
         set.add(destination);
      }
   }

   /**
    * Remove a temporary destination
    */
   public void removeTemporaryDestination(ConnectionToken dc, SpyDestination destination)
   {
      synchronized (tempDests)
      {
         HashSet set = (HashSet) tempDests.get(dc);
         if (set == null)
            return;
         set.remove(destination);
      }
      try
      {
         manager.removeDestination(destination.getName());
      }
      catch (Exception e)
      {
         log.warn("Unable to remove temporary destination " + destination, e);
      }
   }

   /**
    * Remove all temporary destination for a connection
    */
   public void removeTemporaryDestinations(ConnectionToken dc)
   {
      synchronized (tempDests)
      {
         HashSet set = (HashSet) tempDests.remove(dc);
         if (set == null)
            return;
         for (Iterator iterator = set.iterator(); iterator.hasNext();)
         {
            SpyDestination destination = (SpyDestination) iterator.next();
            try
            {
               manager.removeDestination(destination.getName());
            }
            catch (Exception e)
            {
               log.warn("Unable to remove temporary destination " + destination, e);
            }
         }
      }
   }
} // ServerSecurityInvoker