/* Copyright 2002 The JA-SIG Collaborative. All rights reserved.
* See license distributed with this file and
* available online at http://www.uportal.org/license.html
*/
package org.jasig.portal.security.provider;
import java.util.Date;
import java.util.Iterator;
import org.jasig.portal.AuthorizationException;
import org.jasig.portal.groups.GroupsException;
import org.jasig.portal.groups.IGroupMember;
import org.jasig.portal.security.IAuthorizationPrincipal;
import org.jasig.portal.security.IAuthorizationService;
import org.jasig.portal.security.IPermission;
import org.jasig.portal.security.IPermissionPolicy;
/**
* Implements a strategy for answering the basic authorization question: does the
* <code>principal</code> have permission to perform the <code>activity</code> on
* the <code>target</code>.
*
* @author Dan Ellentuck (de3@columbia.edu)
* @version $Revision: 1.7 $
*/
public class DefaultPermissionPolicy implements IPermissionPolicy {
/**
* DefaultPermissionPolicy constructor.
*/
public DefaultPermissionPolicy() {
super();
}
/**
* Answers if the owner has authorized the principal to perform the activity
* on the target, based on permissions provided by the service. Params
* <code>service</code>, <code>owner</code> and <code>activity</code> must
* be non-null.
*
* @return boolean
* @param service org.jasig.portal.security.IAuthorizationService
* @param principal org.jasig.portal.security.IAuthorizationPrincipal
* @param owner java.lang.String
* @param activity java.lang.String
* @param target java.lang.String
* @exception org.jasig.portal.AuthorizationException
*/
public boolean doesPrincipalHavePermission
(IAuthorizationService service,
IAuthorizationPrincipal principal,
String owner,
String activity,
String target)
throws org.jasig.portal.AuthorizationException
{
IPermission[] perms = service.getPermissionsForPrincipal(principal, owner, activity, target);
// We found a permission associated with this principal.
if ( perms.length == 1 )
{ return permissionIsGranted(perms[0]); }
// Should never be.
if ( perms.length > 1 )
{ throw new AuthorizationException("Duplicate permissions for: " + perms[0]); }
// No permissions for this principal. Check inherited permissions.
boolean hasPermission = false;
try
{
Iterator i = service.getGroupMember(principal).getAllContainingGroups();
while ( i.hasNext() && ! hasPermission )
{
IAuthorizationPrincipal prn = service.newPrincipal( (IGroupMember) i.next() );
hasPermission = primDoesPrincipalHavePermission(prn, owner, activity, target, service);
}
}
catch ( GroupsException ge )
{ throw new AuthorizationException(ge); }
return hasPermission;
}
/**
* Checks that the permission is explicitly granted and not expired.
* @return boolean
* @param p org.jasig.portal.security.IPermission
*/
private boolean permissionIsGranted(IPermission p)
{
Date now = new Date();
return
(p.getType().equals(IPermission.PERMISSION_TYPE_GRANT)) &&
(p.getEffective() == null || ! p.getEffective().after(now)) &&
(p.getExpires() == null || p.getExpires().after(now));
}
/**
* Answers if this specific principal (as opposed to its parents) has the permission.
* @return boolean
* @param principal IAuthorizationPrincipal
* @param owner java.lang.String
* @param activity java.lang.String
* @param target java.lang.String
* @exception AuthorizationException indicates authorization information could not
* be retrieved or was invalid.
*/
private boolean primDoesPrincipalHavePermission(
IAuthorizationPrincipal principal,
String owner,
String activity,
String target,
IAuthorizationService service)
throws AuthorizationException
{
IPermission[] perms = service.getPermissionsForPrincipal(principal, owner, activity, target);
if ( perms.length == 0 )
{ return false; }
if ( perms.length == 1 )
{ return permissionIsGranted(perms[0]); }
else
{ throw new AuthorizationException("Duplicate permissions for: " + perms[0]); }
}
}