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 * reserved comment block

 * DO NOT REMOVE OR ALTER!

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/**

 * 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

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package com.sun.org.apache.xml.internal.security.c14n.implementations;

import java.io.IOException;

import java.util.Iterator;

import java.util.Set;

import java.util.SortedSet;

import java.util.TreeSet;

import javax.xml.parsers.ParserConfigurationException;

import com.sun.org.apache.xml.internal.security.c14n.CanonicalizationException;

import com.sun.org.apache.xml.internal.security.c14n.helper.C14nHelper;

import com.sun.org.apache.xml.internal.security.signature.XMLSignatureInput;

import com.sun.org.apache.xml.internal.security.transforms.params.InclusiveNamespaces;

import com.sun.org.apache.xml.internal.security.utils.Constants;

import com.sun.org.apache.xml.internal.security.utils.XMLUtils;

import org.w3c.dom.Attr;

import org.w3c.dom.Document;

import org.w3c.dom.Element;

import org.w3c.dom.NamedNodeMap;

import org.w3c.dom.Node;

import org.xml.sax.SAXException;

/**

 * Implements &quot; <A

 * HREF="http://www.w3.org/TR/2002/REC-xml-exc-c14n-20020718/">Exclusive XML

 * Canonicalization, Version 1.0 </A>&quot; <BR />

 * Credits: During restructuring of the Canonicalizer framework, Ren??

 * Kollmorgen from Software AG submitted an implementation of ExclC14n which

 * fitted into the old architecture and which based heavily on my old (and slow)

 * implementation of "Canonical XML". A big "thank you" to Ren?? for this.

 * <BR />

 * <i>THIS </i> implementation is a complete rewrite of the algorithm.

 *

 * @author Christian Geuer-Pollmann <geuerp@apache.org>

 * @version $Revision: 1147448 $

 * @see <a href="http://www.w3.org/TR/2002/REC-xml-exc-c14n-20020718/ Exclusive#">

 *          XML Canonicalization, Version 1.0</a>

 */

public abstract class Canonicalizer20010315Excl extends CanonicalizerBase {

    private static final String XML_LANG_URI = Constants.XML_LANG_SPACE_SpecNS;

    private static final String XMLNS_URI = Constants.NamespaceSpecNS;

    /**

      * This Set contains the names (Strings like "xmlns" or "xmlns:foo") of

      * the inclusive namespaces.

      */

    private SortedSet<String> inclusiveNSSet;

    private final SortedSet<Attr> result = new TreeSet<Attr>(COMPARE);

    /**

     * Constructor Canonicalizer20010315Excl

     *

     * @param includeComments

     */

    public Canonicalizer20010315Excl(boolean includeComments) {

        super(includeComments);

    }

    /**

     * Method engineCanonicalizeSubTree

     * @inheritDoc

     * @param rootNode

     *

     * @throws CanonicalizationException

     */

    public byte[] engineCanonicalizeSubTree(Node rootNode)

        throws CanonicalizationException {

        return engineCanonicalizeSubTree(rootNode, "", null);

    }

    /**

     * Method engineCanonicalizeSubTree

     *  @inheritDoc

     * @param rootNode

     * @param inclusiveNamespaces

     *

     * @throws CanonicalizationException

     */

    public byte[] engineCanonicalizeSubTree(

        Node rootNode, String inclusiveNamespaces

    ) throws CanonicalizationException {

        return engineCanonicalizeSubTree(rootNode, inclusiveNamespaces, null);

    }

    /**

     * Method engineCanonicalizeSubTree

     * @param rootNode

     * @param inclusiveNamespaces

     * @param excl A element to exclude from the c14n process.

     * @return the rootNode c14n.

     * @throws CanonicalizationException

     */

    public byte[] engineCanonicalizeSubTree(

        Node rootNode, String inclusiveNamespaces, Node excl

    ) throws CanonicalizationException{

        inclusiveNSSet = InclusiveNamespaces.prefixStr2Set(inclusiveNamespaces);

        return super.engineCanonicalizeSubTree(rootNode, excl);

    }

    /**

     *

     * @param rootNode

     * @param inclusiveNamespaces

     * @return the rootNode c14n.

     * @throws CanonicalizationException

     */

    public byte[] engineCanonicalize(

        XMLSignatureInput rootNode, String inclusiveNamespaces

    ) throws CanonicalizationException {

        inclusiveNSSet = InclusiveNamespaces.prefixStr2Set(inclusiveNamespaces);

        return super.engineCanonicalize(rootNode);

    }

    /**

     * Method engineCanonicalizeXPathNodeSet

     * @inheritDoc

     * @param xpathNodeSet

     * @param inclusiveNamespaces

     * @throws CanonicalizationException

     */

    public byte[] engineCanonicalizeXPathNodeSet(

        Set<Node> xpathNodeSet, String inclusiveNamespaces

    ) throws CanonicalizationException {

        inclusiveNSSet = InclusiveNamespaces.prefixStr2Set(inclusiveNamespaces);

        return super.engineCanonicalizeXPathNodeSet(xpathNodeSet);

    }

    @Override

    protected Iterator<Attr> handleAttributesSubtree(Element element, NameSpaceSymbTable ns)

        throws CanonicalizationException {

        // result will contain the attrs which have to be output

        final SortedSet<Attr> result = this.result;

        result.clear();

        // The prefix visibly utilized (in the attribute or in the name) in

        // the element

        SortedSet<String> visiblyUtilized = new TreeSet<String>();

        if (inclusiveNSSet != null && !inclusiveNSSet.isEmpty()) {

            visiblyUtilized.addAll(inclusiveNSSet);

        }

        if (element.hasAttributes()) {

            NamedNodeMap attrs = element.getAttributes();

            int attrsLength = attrs.getLength();

            for (int i = 0; i < attrsLength; i++) {

                Attr attribute = (Attr) attrs.item(i);

                String NName = attribute.getLocalName();

                String NNodeValue = attribute.getNodeValue();

                if (!XMLNS_URI.equals(attribute.getNamespaceURI())) {

                    // Not a namespace definition.

                    // The Element is output element, add the prefix (if used) to

                    // visiblyUtilized

                    String prefix = attribute.getPrefix();

                    if (prefix != null && !(prefix.equals(XML) || prefix.equals(XMLNS))) {

                        visiblyUtilized.add(prefix);

                    }

                    // Add to the result.

                    result.add(attribute);

                } else if (!(XML.equals(NName) && XML_LANG_URI.equals(NNodeValue))

                    && ns.addMapping(NName, NNodeValue, attribute)

                    && C14nHelper.namespaceIsRelative(NNodeValue)) {

                    // The default mapping for xml must not be output.

                    // New definition check if it is relative.

                    Object exArgs[] = {element.getTagName(), NName, attribute.getNodeValue()};

                    throw new CanonicalizationException(

                        "c14n.Canonicalizer.RelativeNamespace", exArgs

                    );

                }

            }

        }

        String prefix = null;

        if (element.getNamespaceURI() != null

            && !(element.getPrefix() == null || element.getPrefix().length() == 0)) {

            prefix = element.getPrefix();

        } else {

            prefix = XMLNS;

        }

        visiblyUtilized.add(prefix);

        for (String s : visiblyUtilized) {

            Attr key = ns.getMapping(s);

            if (key != null) {

                result.add(key);

            }

        }

        return result.iterator();

    }

    /**

     * @inheritDoc

     * @param element

     * @throws CanonicalizationException

     */

    @Override

    protected final Iterator<Attr> handleAttributes(Element element, NameSpaceSymbTable ns)

        throws CanonicalizationException {

        // result will contain the attrs which have to be output

        final SortedSet<Attr> result = this.result;

        result.clear();

        // The prefix visibly utilized (in the attribute or in the name) in

        // the element

        Set<String> visiblyUtilized = null;

        // It's the output selected.

        boolean isOutputElement = isVisibleDO(element, ns.getLevel()) == 1;

        if (isOutputElement) {

            visiblyUtilized = new TreeSet<String>();

            if (inclusiveNSSet != null && !inclusiveNSSet.isEmpty()) {

                visiblyUtilized.addAll(inclusiveNSSet);

            }

        }

        if (element.hasAttributes()) {

            NamedNodeMap attrs = element.getAttributes();

            int attrsLength = attrs.getLength();

            for (int i = 0; i < attrsLength; i++) {

                Attr attribute = (Attr) attrs.item(i);

                String NName = attribute.getLocalName();

                String NNodeValue = attribute.getNodeValue();

                if (!XMLNS_URI.equals(attribute.getNamespaceURI())) {

                    if (isVisible(attribute) && isOutputElement) {

                        // The Element is output element, add the prefix (if used)

                        // to visibyUtilized

                        String prefix = attribute.getPrefix();

                        if (prefix != null && !(prefix.equals(XML) || prefix.equals(XMLNS))) {

                            visiblyUtilized.add(prefix);

                        }

                        // Add to the result.

                        result.add(attribute);

                    }

                } else if (isOutputElement && !isVisible(attribute) && !XMLNS.equals(NName)) {

                    ns.removeMappingIfNotRender(NName);

                } else {

                    if (!isOutputElement && isVisible(attribute)

                        && inclusiveNSSet.contains(NName)

                        && !ns.removeMappingIfRender(NName)) {

                        Node n = ns.addMappingAndRender(NName, NNodeValue, attribute);

                        if (n != null) {

                            result.add((Attr)n);

                            if (C14nHelper.namespaceIsRelative(attribute)) {

                                Object exArgs[] = { element.getTagName(), NName, attribute.getNodeValue() };

                                throw new CanonicalizationException(

                                    "c14n.Canonicalizer.RelativeNamespace", exArgs

                                );

                            }

                        }

                    }

                    if (ns.addMapping(NName, NNodeValue, attribute)

                        && C14nHelper.namespaceIsRelative(NNodeValue)) {

                        // New definition check if it is relative

                        Object exArgs[] = { element.getTagName(), NName, attribute.getNodeValue() };

                        throw new CanonicalizationException(

                            "c14n.Canonicalizer.RelativeNamespace", exArgs

                        );

                    }

                }

            }

        }

        if (isOutputElement) {

            // The element is visible, handle the xmlns definition

            Attr xmlns = element.getAttributeNodeNS(XMLNS_URI, XMLNS);

            if (xmlns != null && !isVisible(xmlns)) {

                // There is a definition but the xmlns is not selected by the

                // xpath. then xmlns=""

            }

            String prefix = null;

            if (element.getNamespaceURI() != null

                && !(element.getPrefix() == null || element.getPrefix().length() == 0)) {

                prefix = element.getPrefix();

            } else {

                prefix = XMLNS;

            }

            visiblyUtilized.add(prefix);

            for (String s : visiblyUtilized) {

                Attr key = ns.getMapping(s);

                if (key != null) {

                    result.add(key);

                }

            }

        }

        return result.iterator();

    }

    protected void circumventBugIfNeeded(XMLSignatureInput input)

        throws CanonicalizationException, ParserConfigurationException,

               IOException, SAXException {

        if (!input.isNeedsToBeExpanded() || inclusiveNSSet.isEmpty() || inclusiveNSSet.isEmpty()) {

            return;

        }

        Document doc = null;

        if (input.getSubNode() != null) {

            doc = XMLUtils.getOwnerDocument(input.getSubNode());

        } else {

            doc = XMLUtils.getOwnerDocument(input.getNodeSet());

        }

        XMLUtils.circumventBug2650(doc);

    }

}