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	/*
	* Copyright (c) 2013, 2021, Oracle and/or its affiliates. All rights reserved.
	*/
	/*
	* Licensed to the Apache Software Foundation (ASF) under one or more
	* contributor license agreements. See the NOTICE file distributed with
	* this work for additional information regarding copyright ownership.
	* The ASF licenses this file to You under the Apache License, Version 2.0
	* (the "License"); you may not use this file except in compliance with
	* the License. You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	package com.sun.org.apache.xerces.internal.util;

	import jdk.xml.internal.JdkConstants;

	/**
	* This class is a container for parser settings that relate to security, or
	* more specifically, it is intended to be used to prevent denial-of-service
	* attacks from being launched against a system running Xerces. Any component
	* that is aware of a denial-of-service attack that can arise from its
	* processing of a certain kind of document may query its Component Manager for
	* the property (http://apache.org/xml/properties/security-manager) whose value
	* will be an instance of this class. If no value has been set for the property,
	* the component should proceed in the "usual" (spec-compliant) manner. If a
	* value has been set, then it must be the case that the component in question
	* needs to know what method of this class to query. This class will provide
	* defaults for all known security issues, but will also provide setters so that
	* those values can be tailored by applications that care.
	*
	* @author Neil Graham, IBM
	* @LastModified: May 2021
	*/
	public final class SecurityManager {

	//
	// Constants
	//
	// default value for entity expansion limit
	private final static int DEFAULT_ENTITY_EXPANSION_LIMIT = 64000;

	/**
	* Default value of number of nodes created. *
	*/
	private final static int DEFAULT_MAX_OCCUR_NODE_LIMIT = 5000;

	//
	// Data
	//
	private final static int DEFAULT_ELEMENT_ATTRIBUTE_LIMIT = 10000;

	/**
	* Entity expansion limit. *
	*/
	private int entityExpansionLimit;

	/**
	* W3C XML Schema maxOccurs limit. *
	*/
	private int maxOccurLimit;

	private int fElementAttributeLimit;

	// default constructor. Establishes default values for
	// all known security holes.
	/**
	* Default constructor. Establishes default values for known security
	* vulnerabilities.
	*/
	public SecurityManager() {
	entityExpansionLimit = DEFAULT_ENTITY_EXPANSION_LIMIT;
	maxOccurLimit = DEFAULT_MAX_OCCUR_NODE_LIMIT;
	fElementAttributeLimit = DEFAULT_ELEMENT_ATTRIBUTE_LIMIT;
	//We are reading system properties only once ,
	//at the time of creation of this object ,
	readSystemProperties();
	}

	/**
	* <p>
	* Sets the number of entity expansions that the parser should permit in a
	* document.</p>
	*
	* @param limit the number of entity expansions permitted in a document
	*/
	public void setEntityExpansionLimit(int limit) {
	entityExpansionLimit = limit;
	}

	/**
	* <p>
	* Returns the number of entity expansions that the parser permits in a
	* document.</p>
	*
	* @return the number of entity expansions permitted in a document
	*/
	public int getEntityExpansionLimit() {
	return entityExpansionLimit;
	}

	/**
	* <p>
	* Sets the limit of the number of content model nodes that may be created
	* when building a grammar for a W3C XML Schema that contains maxOccurs
	* attributes with values other than "unbounded".</p>
	*
	* @param limit the maximum value for maxOccurs other than "unbounded"
	*/
	public void setMaxOccurNodeLimit(int limit) {
	maxOccurLimit = limit;
	}

	/**
	* <p>
	* Returns the limit of the number of content model nodes that may be
	* created when building a grammar for a W3C XML Schema that contains
	* maxOccurs attributes with values other than "unbounded".</p>
	*
	* @return the maximum value for maxOccurs other than "unbounded"
	*/
	public int getMaxOccurNodeLimit() {
	return maxOccurLimit;
	}

	public int getElementAttrLimit() {
	return fElementAttributeLimit;
	}

	public void setElementAttrLimit(int limit) {
	fElementAttributeLimit = limit;
	}

	private void readSystemProperties() {

	try {
	String value = System.getProperty(JdkConstants.ENTITY_EXPANSION_LIMIT);
	if (value != null && !value.equals("")) {
	entityExpansionLimit = Integer.parseInt(value);
	if (entityExpansionLimit < 0) {
	entityExpansionLimit = DEFAULT_ENTITY_EXPANSION_LIMIT;
	}
	} else {
	entityExpansionLimit = DEFAULT_ENTITY_EXPANSION_LIMIT;
	}
	} catch (Exception ex) {
	}

	try {
	String value = System.getProperty(JdkConstants.MAX_OCCUR_LIMIT);
	if (value != null && !value.equals("")) {
	maxOccurLimit = Integer.parseInt(value);
	if (maxOccurLimit < 0) {
	maxOccurLimit = DEFAULT_MAX_OCCUR_NODE_LIMIT;
	}
	} else {
	maxOccurLimit = DEFAULT_MAX_OCCUR_NODE_LIMIT;
	}
	} catch (Exception ex) {
	}

	try {
	String value = System.getProperty(JdkConstants.ELEMENT_ATTRIBUTE_LIMIT);
	if (value != null && !value.equals("")) {
	fElementAttributeLimit = Integer.parseInt(value);
	if (fElementAttributeLimit < 0) {
	fElementAttributeLimit = DEFAULT_ELEMENT_ATTRIBUTE_LIMIT;
	}
	} else {
	fElementAttributeLimit = DEFAULT_ELEMENT_ATTRIBUTE_LIMIT;
	}

	} catch (Exception ex) {
	}

	}

	} // class SecurityManager

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