SecurityContextStack.java
/*
** Module : SecurityContextStack.java
** Abstract : Class that manages security context switches for server threads.
**
** Copyright (c) 2004-2025, Golden Code Development Corporation.
**
** -#- -I- --Date-- --JPRM-- ----------------------------------Description-----------------------------------
** 001 NVS 20050314 @20318 Created the initial implementation of SecurityContextStack class.
** 002 NVS 20050427 @20912 Enhanced to provide unlimited storage for any kind of tokens
** (objects) that can be associated with this context. The need is to
** get rid of all sorts of per thread state information and replace it
** with per context one. This overcomes the problem of arbitrary chosen
** threads from the thread pool to serve elementary requests which have
** share some state for the lifespan of the session.
** 003 NVS 20050505 @21106 Added new method getEffectiveContext() which is required to
** implement dropInitialSecurityContext() in SecurityManager. Changed
** the implementation of other methods to benefit from this new one.
** Added a method to access the generation of the security cache this
** context is currently bound to.
** 004 ECF 20060120 @24005 Modified {add|remove|has|get}Token methods. Replaced String token
** name with an Object key.
** 005 NVS 20070412 @32966 Removed an excessive logging call from push() method.
** 006 GES 20111109 Added duplicate().
** 007 IAS 20160407 Fixed "system-security-editing" processing, use synthetic key as
** context key.
** 008 GES 20200205 Added a mechanism to create a copy that doesn't share mutable state.
** 009 GES 20210917 Rework to better encapsulate decision caching.
** 010 GBB 20250403 Casting replaced with generics.
*/
/*
** This program is free software: you can redistribute it and/or modify
** it under the terms of the GNU Affero General Public License as
** published by the Free Software Foundation, either version 3 of the
** License, or (at your option) any later version.
**
** This program 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 Affero General Public License for more details.
**
** You may find a copy of the GNU Affero GPL version 3 at the following
** location: https://www.gnu.org/licenses/agpl-3.0.en.html
**
** Additional terms under GNU Affero GPL version 3 section 7:
**
** Under Section 7 of the GNU Affero GPL version 3, the following additional
** terms apply to the works covered under the License. These additional terms
** are non-permissive additional terms allowed under Section 7 of the GNU
** Affero GPL version 3 and may not be removed by you.
**
** 0. Attribution Requirement.
**
** You must preserve all legal notices or author attributions in the covered
** work or Appropriate Legal Notices displayed by works containing the covered
** work. You may not remove from the covered work any author or developer
** credit already included within the covered work.
**
** 1. No License To Use Trademarks.
**
** This license does not grant any license or rights to use the trademarks
** Golden Code, FWD, any Golden Code or FWD logo, or any other trademarks
** of Golden Code Development Corporation. You are not authorized to use the
** name Golden Code, FWD, or the names of any author or contributor, for
** publicity purposes without written authorization.
**
** 2. No Misrepresentation of Affiliation.
**
** You may not represent yourself as Golden Code Development Corporation or FWD.
**
** You may not represent yourself for publicity purposes as associated with
** Golden Code Development Corporation, FWD, or any author or contributor to
** the covered work, without written authorization.
**
** 3. No Misrepresentation of Source or Origin.
**
** You may not represent the covered work as solely your work. All modified
** versions of the covered work must be marked in a reasonable way to make it
** clear that the modified work is not originating from Golden Code Development
** Corporation or FWD. All modified versions must contain the notices of
** attribution required in this license.
*/
package com.goldencode.p2j.security;
/**
* Security context stack is a mechanism of tracking security context switches
* within a thread.
*/
class SecurityContextStack
{
/** Opaque key for the "system-security-editing" */
private static final ContextKey SYSTEM_SECURITY_EDITING = new ContextKey();
/** Per-thread reference to the security context. */
private static ThreadLocal<SecurityContextStack> contextPointer = new ThreadLocal<>();
/** The initial context. */
private SecurityContext initial = null;
/** The effective context (if not <code>null</code>). */
private SecurityContext additional = null;
/**
* Package private constructor.
*
* @param initial
* The initial security context to use.
*/
SecurityContextStack(SecurityContext initial)
{
this.initial = initial;
}
/**
* Gets the current security context stack.
*
* @return <code>SecurityContextStack</code> object for the current thread
* or <code>null</code> if not initialized
*/
static SecurityContextStack getContext()
{
return contextPointer.get();
}
/**
* Sets the current security context stack.
*
* @param stack
* <code>SecurityContextStack</code> object to be set for
* the current thread
*/
static void setContext(SecurityContextStack stack)
{
contextPointer.set(stack);
}
/**
* Create a copy of this stack with shared initial and effective contexts.
*
* @return The copy which has shared contexts.
*/
SecurityContextStack duplicate()
{
SecurityContextStack dup = new SecurityContextStack(initial);
dup.additional = additional;
return dup;
}
/**
* Create a copy of this stack with the initial context set from the current effective
* context BUT with no shared data and no existing session. The intention is to provide all
* the state needed to quickly create a new session that is related to the current session
* but which is independent. The copied state will include the subjects and ACLs of the
* existing session but will exclude context-local data.
*
* @return The copy which is related.
*/
SecurityContextStack related()
{
return new SecurityContextStack(new SecurityContext(getEffectiveContext()));
}
/**
* Gets the effective security context.
*
* @return <code>SecurityContext</code> object for the current thread
*/
SecurityContext getEffectiveContext()
{
return (additional != null) ? additional : initial;
}
/**
* Gets the current check list for the context.
*
* @return an array of indices into accounts that represent this security
* context
*/
int[] getCheckList()
{
return getEffectiveContext().getCheckList();
}
/**
* Gets the array of original subject IDs of this context.
*
* @return array of indices into accounts
*/
int[] getIdList()
{
return getEffectiveContext().getIdList();
}
/**
* Get the access decision cache for the context.
*
* @param resource
* The unique index that identifies the resource type.
*
* @return map containing access decisions
*/
Decision getDecisionCache(int resource)
{
return getEffectiveContext().getDecisionCache(resource);
}
/**
* Conditionally pushes an additional security context to the stack.
*
* @return <code>true</code> if successful
*/
boolean push(SecurityContext ctx)
{
if (additional != null || !initial.isInitial() || ctx.isInitial())
return false;
additional = ctx;
return true;
}
/**
* Conditionally pops an additional security context off the stack.
*
* @return <code>true</code> if successful
*/
SecurityContext pop()
{
SecurityContext ctx = additional;
additional = null;
return ctx;
}
/**
* Gets the context that is the session key object.
*
* @return security context instance or <code>null</code>
*/
SecurityContext getSessionKey()
{
return additional;
}
/**
* Gets the initial context.
*
* @return security context instance or <code>null</code>
*/
SecurityContext getInitial()
{
return initial;
}
/**
* Gets the batch editing status.
*
* @return <code>true</code> if an editing batch is open for this context
*/
boolean isEditing()
{
return hasToken(SYSTEM_SECURITY_EDITING);
}
/**
* Sets the batch editing status.
*
* @param isEditing
* new state of the batch editing for this context
*/
void setEditing(boolean isEditing)
{
SecurityContext ctx = getEffectiveContext();
if (isEditing)
ctx.addToken(SYSTEM_SECURITY_EDITING, Boolean.TRUE);
else
ctx.removeToken(SYSTEM_SECURITY_EDITING);
}
/**
* Adds a token to the context map.
*
* @param key
* token key to be used as a key in the map
*
* @param token
* an arbitrary object to be kept in the entry
*
* @return <code>true</code> if the token is added successfully
*/
boolean addToken(ContextKey key, Object token)
{
return getEffectiveContext().addToken(key, token);
}
/**
* Remove a token from the context map.
*
* @param key
* token key to be used as a key in the map
*
* @return <code>true</code> if the token was removed successfully
*/
boolean removeToken(ContextKey key)
{
return getEffectiveContext().removeToken(key);
}
/**
* Checks whether the specified token is in the context map.
*
* @param key
* token key to be used as a key in the map
*
* @return <code>true</code> if the token is found
*/
boolean hasToken(ContextKey key)
{
return getEffectiveContext().hasToken(key);
}
/**
* Gets the token from the context map.
*
* @param key
* token key to be used as a key in the map
*
* @return the value of the token as a generic object or <code>null</code>
*/
Object getToken(ContextKey key)
{
return getEffectiveContext().getToken(key);
}
/**
* Gets the security cache this context stack is bound to.
*
* @return <code>SecurityCache</code>
*/
SecurityCache getCache()
{
return getEffectiveContext().getCache();
}
}