/*

 * reserved comment block

 * DO NOT REMOVE OR ALTER!

 */

/*

 * The Apache Software License, Version 1.1

 *

 *

 * Copyright (c) 2003 The Apache Software Foundation.

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 *

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 *

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in

 *    the documentation and/or other materials provided with the

 *    distribution.

 *

 * 3. The end-user documentation included with the redistribution,

 *    if any, must include the following acknowledgment:

 *       "This product includes software developed by the

 *        Apache Software Foundation (http://www.apache.org/)."

 *    Alternately, this acknowledgment may appear in the software itself,

 *    if and wherever such third-party acknowledgments normally appear.

 *

 * 4. The names "Xerces" and "Apache Software Foundation" must

 *    not be used to endorse or promote products derived from this

 *    software without prior written permission. For written

 *    permission, please contact apache@apache.org.

 *

 * 5. Products derived from this software may not be called "Apache",

 *    nor may "Apache" appear in their name, without prior written

 *    permission of the Apache Software Foundation.

 *

 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED

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 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR

 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF

 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND

 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,

 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT

 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

 * SUCH DAMAGE.

 * ====================================================================

 *

 * This software consists of voluntary contributions made by many

 * individuals on behalf of the Apache Software Foundation and was

 * originally based on software copyright (c) 1999, International

 * Business Machines, Inc., http://www.apache.org.  For more

 * information on the Apache Software Foundation, please see

 * <http://www.apache.org/>.

 */

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

import com.sun.org.apache.xerces.internal.impl.Constants;

/**

 * 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

 *

 */

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(Constants.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(Constants.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(Constants.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