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

    
W3C XML Schema maxOccurs limit. /** 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.
/**
     * 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();
    }

    
Sets the number of entity expansions that the
parser should permit in a document.
Params:
limit – the number of entity expansions
permitted in a document/**
     * <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;
    }

    
Returns the number of entity expansions
that the parser permits in a document.
Returns:
the number of entity expansions
permitted in a document/**
     * <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;
    }

    
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".
Params:
limit – the maximum value for maxOccurs other
than "unbounded"/**
     * <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;
    }

    
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".
Returns:
the maximum value for maxOccurs other
than "unbounded"/**
     * <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