All Downloads are FREE. Search and download functionalities are using the official Maven repository.

org.apache.xml.security.utils.XMLUtils Maven / Gradle / Ivy

Go to download

Apache XML Security for Java supports XML-Signature Syntax and Processing, W3C Recommendation 12 February 2002, and XML Encryption Syntax and Processing, W3C Recommendation 10 December 2002. As of version 1.4, the library supports the standard Java API JSR-105: XML Digital Signature APIs.

There is a newer version: 4.0.2
Show newest version
/**
 * 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 org.apache.xml.security.utils;

import java.io.IOException;
import java.io.OutputStream;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Set;

import org.apache.xml.security.c14n.CanonicalizationException;
import org.apache.xml.security.c14n.Canonicalizer;
import org.apache.xml.security.c14n.InvalidCanonicalizerException;
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.w3c.dom.NodeList;
import org.w3c.dom.ProcessingInstruction;
import org.w3c.dom.Text;

/**
 * DOM and XML accessibility and comfort functions.
 *
 * @author Christian Geuer-Pollmann
 */
public class XMLUtils {

    private static boolean ignoreLineBreaks =
        AccessController.doPrivileged(new PrivilegedAction() {
            public Boolean run() {
                return Boolean.valueOf(Boolean.getBoolean
                    ("org.apache.xml.security.ignoreLineBreaks"));
            }
        }).booleanValue();
    
    private static volatile String dsPrefix = "ds";
    private static volatile String xencPrefix = "xenc";
    private static volatile String xenc11Prefix = "xenc11";
    
    /** {@link org.apache.commons.logging} logging facility */
    private static final org.apache.commons.logging.Log log = 
        org.apache.commons.logging.LogFactory.getLog(XMLUtils.class);


    /**
     * Constructor XMLUtils
     *
     */
    private XMLUtils() {
        // we don't allow instantiation
    }
    
    /**
     * Set the prefix for the digital signature namespace
     * @param prefix the new prefix for the digital signature namespace
     */
    public static void setDsPrefix(String prefix) {
        dsPrefix = prefix;
    }
    
    /**
     * Set the prefix for the encryption namespace
     * @param prefix the new prefix for the encryption namespace
     */
    public static void setXencPrefix(String prefix) {
        xencPrefix = prefix;
    }
    
    /**
     * Set the prefix for the encryption namespace 1.1
     * @param prefix the new prefix for the encryption namespace 1.1
     */
    public static void setXenc11Prefix(String prefix) {
        xenc11Prefix = prefix;
    }
    
    public static Element getNextElement(Node el) {
        while ((el != null) && (el.getNodeType() != Node.ELEMENT_NODE)) {
            el = el.getNextSibling();
        }
        return (Element)el;
    }

    /**
     * @param rootNode
     * @param result
     * @param exclude
     * @param com whether comments or not
     */   
    public static void getSet(Node rootNode, Set result, Node exclude, boolean com) {
        if ((exclude != null) && isDescendantOrSelf(exclude, rootNode)) {
            return;
        }
        getSetRec(rootNode, result, exclude, com);
    }
    
    @SuppressWarnings("fallthrough")
    private static void getSetRec(final Node rootNode, final Set result,
                                final Node exclude, final boolean com) {
        if (rootNode == exclude) {
            return;
        }
        switch (rootNode.getNodeType()) {   	   		   	   			
        case Node.ELEMENT_NODE:
            result.add(rootNode);
            Element el = (Element)rootNode;
            if (el.hasAttributes()) {
                NamedNodeMap nl = el.getAttributes();
                for (int i = 0;i < nl.getLength(); i++) {
                    result.add(nl.item(i));
                }
            }
            //no return keep working
        case Node.DOCUMENT_NODE:   	   			
            for (Node r = rootNode.getFirstChild(); r != null; r = r.getNextSibling()) {                                    
                if (r.getNodeType() == Node.TEXT_NODE) {
                    result.add(r); 
                    while ((r != null) && (r.getNodeType() == Node.TEXT_NODE)) {
                        r = r.getNextSibling();
                    }
                    if (r == null) {
                        return;
                    }
                }  
                getSetRec(r, result, exclude, com);                
            }
            return;
        case Node.COMMENT_NODE:
            if (com) {
                result.add(rootNode);
            }
            return;
        case Node.DOCUMENT_TYPE_NODE:
            return;
        default:
            result.add(rootNode);
        }
    }


    /**
     * Outputs a DOM tree to an {@link OutputStream}.
     *
     * @param contextNode root node of the DOM tree
     * @param os the {@link OutputStream}
     */
    public static void outputDOM(Node contextNode, OutputStream os) {
        XMLUtils.outputDOM(contextNode, os, false);
    }

    /**
     * Outputs a DOM tree to an {@link OutputStream}. If an Exception is
     * thrown during execution, it's StackTrace is output to System.out, but the
     * Exception is not re-thrown.
     *
     * @param contextNode root node of the DOM tree
     * @param os the {@link OutputStream}
     * @param addPreamble
     */
    public static void outputDOM(Node contextNode, OutputStream os, boolean addPreamble) {
        try {
            if (addPreamble) {
                os.write("\n".getBytes("UTF-8"));
            }

            os.write(Canonicalizer.getInstance(
                Canonicalizer.ALGO_ID_C14N_WITH_COMMENTS).canonicalizeSubtree(contextNode)
            );
        } catch (IOException ex) {
            if (log.isDebugEnabled()) {
                log.debug(ex);
            }
        }
        catch (InvalidCanonicalizerException ex) {
            if (log.isDebugEnabled()) {
                log.debug(ex);
            }
            ex.printStackTrace();
        } catch (CanonicalizationException ex) {
            if (log.isDebugEnabled()) {
                log.debug(ex);
            }
            ex.printStackTrace();
        }
    }

    /**
     * Serializes the contextNode into the OutputStream, but
     * suppresses all Exceptions.
     * 
* NOTE: This should only be used for debugging purposes, * NOT in a production environment; this method ignores all exceptions, * so you won't notice if something goes wrong. If you're asking what is to * be used in a production environment, simply use the code inside the * try{} statement, but handle the Exceptions appropriately. * * @param contextNode * @param os */ public static void outputDOMc14nWithComments(Node contextNode, OutputStream os) { try { os.write(Canonicalizer.getInstance( Canonicalizer.ALGO_ID_C14N_WITH_COMMENTS).canonicalizeSubtree(contextNode) ); } catch (IOException ex) { if (log.isDebugEnabled()) { log.debug(ex); } // throw new RuntimeException(ex.getMessage()); } catch (InvalidCanonicalizerException ex) { if (log.isDebugEnabled()) { log.debug(ex); } // throw new RuntimeException(ex.getMessage()); } catch (CanonicalizationException ex) { if (log.isDebugEnabled()) { log.debug(ex); } // throw new RuntimeException(ex.getMessage()); } } /** * Method getFullTextChildrenFromElement * * @param element * @return the string of children */ public static String getFullTextChildrenFromElement(Element element) { StringBuilder sb = new StringBuilder(); Node child = element.getFirstChild(); while (child != null) { if (child.getNodeType() == Node.TEXT_NODE) { sb.append(((Text)child).getData()); } child = child.getNextSibling(); } return sb.toString(); } /** * Creates an Element in the XML Signature specification namespace. * * @param doc the factory Document * @param elementName the local name of the Element * @return the Element */ public static Element createElementInSignatureSpace(Document doc, String elementName) { if (doc == null) { throw new RuntimeException("Document is null"); } if ((dsPrefix == null) || (dsPrefix.length() == 0)) { return doc.createElementNS(Constants.SignatureSpecNS, elementName); } return doc.createElementNS(Constants.SignatureSpecNS, dsPrefix + ":" + elementName); } /** * Creates an Element in the XML Encryption specification namespace. * * @param doc the factory Document * @param elementName the local name of the Element * @return the Element */ public static Element createElementInEncryptionSpace(Document doc, String elementName) { if (doc == null) { throw new RuntimeException("Document is null"); } if ((xencPrefix == null) || (xencPrefix.length() == 0)) { return doc.createElementNS(EncryptionConstants.EncryptionSpecNS, elementName); } return doc.createElementNS( EncryptionConstants.EncryptionSpecNS, xencPrefix + ":" + elementName ); } /** * Creates an Element in the XML Encryption 1.1 specification namespace. * * @param doc the factory Document * @param elementName the local name of the Element * @return the Element */ public static Element createElementInEncryption11Space(Document doc, String elementName) { if (doc == null) { throw new RuntimeException("Document is null"); } if ((xenc11Prefix == null) || (xenc11Prefix.length() == 0)) { return doc.createElementNS(EncryptionConstants.EncryptionSpec11NS, elementName); } return doc.createElementNS( EncryptionConstants.EncryptionSpec11NS, xenc11Prefix + ":" + elementName ); } /** * Returns true if the element is in XML Signature namespace and the local * name equals the supplied one. * * @param element * @param localName * @return true if the element is in XML Signature namespace and the local name equals * the supplied one */ public static boolean elementIsInSignatureSpace(Element element, String localName) { if (element == null){ return false; } return Constants.SignatureSpecNS.equals(element.getNamespaceURI()) && element.getLocalName().equals(localName); } /** * Returns true if the element is in XML Encryption namespace and the local * name equals the supplied one. * * @param element * @param localName * @return true if the element is in XML Encryption namespace and the local name * equals the supplied one */ public static boolean elementIsInEncryptionSpace(Element element, String localName) { if (element == null){ return false; } return EncryptionConstants.EncryptionSpecNS.equals(element.getNamespaceURI()) && element.getLocalName().equals(localName); } /** * Returns true if the element is in XML Encryption 1.1 namespace and the local * name equals the supplied one. * * @param element * @param localName * @return true if the element is in XML Encryption 1.1 namespace and the local name * equals the supplied one */ public static boolean elementIsInEncryption11Space(Element element, String localName) { if (element == null){ return false; } return EncryptionConstants.EncryptionSpec11NS.equals(element.getNamespaceURI()) && element.getLocalName().equals(localName); } /** * This method returns the owner document of a particular node. * This method is necessary because it always returns a * {@link Document}. {@link Node#getOwnerDocument} returns null * if the {@link Node} is a {@link Document}. * * @param node * @return the owner document of the node */ public static Document getOwnerDocument(Node node) { if (node.getNodeType() == Node.DOCUMENT_NODE) { return (Document) node; } try { return node.getOwnerDocument(); } catch (NullPointerException npe) { throw new NullPointerException(I18n.translate("endorsed.jdk1.4.0") + " Original message was \"" + npe.getMessage() + "\""); } } /** * This method returns the first non-null owner document of the Nodes in this Set. * This method is necessary because it always returns a * {@link Document}. {@link Node#getOwnerDocument} returns null * if the {@link Node} is a {@link Document}. * * @param xpathNodeSet * @return the owner document */ public static Document getOwnerDocument(Set xpathNodeSet) { NullPointerException npe = null; for (Node node : xpathNodeSet) { int nodeType = node.getNodeType(); if (nodeType == Node.DOCUMENT_NODE) { return (Document) node; } try { if (nodeType == Node.ATTRIBUTE_NODE) { return ((Attr)node).getOwnerElement().getOwnerDocument(); } return node.getOwnerDocument(); } catch (NullPointerException e) { npe = e; } } throw new NullPointerException(I18n.translate("endorsed.jdk1.4.0") + " Original message was \"" + (npe == null ? "" : npe.getMessage()) + "\""); } /** * Method createDSctx * * @param doc * @param prefix * @param namespace * @return the element. */ public static Element createDSctx(Document doc, String prefix, String namespace) { if ((prefix == null) || (prefix.trim().length() == 0)) { throw new IllegalArgumentException("You must supply a prefix"); } Element ctx = doc.createElementNS(null, "namespaceContext"); ctx.setAttributeNS(Constants.NamespaceSpecNS, "xmlns:" + prefix.trim(), namespace); return ctx; } /** * Method addReturnToElement * * @param e */ public static void addReturnToElement(Element e) { if (!ignoreLineBreaks) { Document doc = e.getOwnerDocument(); e.appendChild(doc.createTextNode("\n")); } } public static void addReturnToElement(Document doc, HelperNodeList nl) { if (!ignoreLineBreaks) { nl.appendChild(doc.createTextNode("\n")); } } public static void addReturnBeforeChild(Element e, Node child) { if (!ignoreLineBreaks) { Document doc = e.getOwnerDocument(); e.insertBefore(doc.createTextNode("\n"), child); } } /** * Method convertNodelistToSet * * @param xpathNodeSet * @return the set with the nodelist */ public static Set convertNodelistToSet(NodeList xpathNodeSet) { if (xpathNodeSet == null) { return new HashSet(); } int length = xpathNodeSet.getLength(); Set set = new HashSet(length); for (int i = 0; i < length; i++) { set.add(xpathNodeSet.item(i)); } return set; } /** * This method spreads all namespace attributes in a DOM document to their * children. This is needed because the XML Signature XPath transform * must evaluate the XPath against all nodes in the input, even against * XPath namespace nodes. Through a bug in XalanJ2, the namespace nodes are * not fully visible in the Xalan XPath model, so we have to do this by * hand in DOM spaces so that the nodes become visible in XPath space. * * @param doc * @see * Namespace axis resolution is not XPath compliant */ public static void circumventBug2650(Document doc) { Element documentElement = doc.getDocumentElement(); // if the document element has no xmlns definition, we add xmlns="" Attr xmlnsAttr = documentElement.getAttributeNodeNS(Constants.NamespaceSpecNS, "xmlns"); if (xmlnsAttr == null) { documentElement.setAttributeNS(Constants.NamespaceSpecNS, "xmlns", ""); } XMLUtils.circumventBug2650internal(doc); } /** * This is the work horse for {@link #circumventBug2650}. * * @param node * @see * Namespace axis resolution is not XPath compliant */ @SuppressWarnings("fallthrough") private static void circumventBug2650internal(Node node) { Node parent = null; Node sibling = null; final String namespaceNs = Constants.NamespaceSpecNS; do { switch (node.getNodeType()) { case Node.ELEMENT_NODE : Element element = (Element) node; if (!element.hasChildNodes()) { break; } if (element.hasAttributes()) { NamedNodeMap attributes = element.getAttributes(); int attributesLength = attributes.getLength(); for (Node child = element.getFirstChild(); child!=null; child = child.getNextSibling()) { if (child.getNodeType() != Node.ELEMENT_NODE) { continue; } Element childElement = (Element) child; for (int i = 0; i < attributesLength; i++) { Attr currentAttr = (Attr) attributes.item(i); if (!namespaceNs.equals(currentAttr.getNamespaceURI())) continue; if (childElement.hasAttributeNS(namespaceNs, currentAttr.getLocalName())) { continue; } childElement.setAttributeNS(namespaceNs, currentAttr.getName(), currentAttr.getNodeValue()); } } } case Node.ENTITY_REFERENCE_NODE : parent = node; sibling = node.getFirstChild(); break; case Node.DOCUMENT_NODE : parent = node; sibling = node.getFirstChild(); break; } while ((sibling == null) && (parent != null)) { sibling = parent.getNextSibling(); parent = parent.getParentNode(); } if (sibling == null) { return; } node = sibling; sibling = node.getNextSibling(); } while (true); } /** * @param sibling * @param nodeName * @param number * @return nodes with the constraint */ public static Element selectDsNode(Node sibling, String nodeName, int number) { while (sibling != null) { if (Constants.SignatureSpecNS.equals(sibling.getNamespaceURI()) && sibling.getLocalName().equals(nodeName)) { if (number == 0){ return (Element)sibling; } number--; } sibling = sibling.getNextSibling(); } return null; } /** * @param sibling * @param nodeName * @param number * @return nodes with the constrain */ public static Element selectXencNode(Node sibling, String nodeName, int number) { while (sibling != null) { if (EncryptionConstants.EncryptionSpecNS.equals(sibling.getNamespaceURI()) && sibling.getLocalName().equals(nodeName)) { if (number == 0){ return (Element)sibling; } number--; } sibling = sibling.getNextSibling(); } return null; } /** * @param sibling * @param nodeName * @param number * @return nodes with the constrain */ public static Text selectDsNodeText(Node sibling, String nodeName, int number) { Node n = selectDsNode(sibling,nodeName,number); if (n == null) { return null; } n = n.getFirstChild(); while (n != null && n.getNodeType() != Node.TEXT_NODE) { n = n.getNextSibling(); } return (Text)n; } /** * @param sibling * @param uri * @param nodeName * @param number * @return nodes with the constrain */ public static Text selectNodeText(Node sibling, String uri, String nodeName, int number) { Node n = selectNode(sibling,uri,nodeName,number); if (n == null) { return null; } n = n.getFirstChild(); while (n != null && n.getNodeType() != Node.TEXT_NODE) { n = n.getNextSibling(); } return (Text)n; } /** * @param sibling * @param uri * @param nodeName * @param number * @return nodes with the constrain */ public static Element selectNode(Node sibling, String uri, String nodeName, int number) { while (sibling != null) { if (sibling.getNamespaceURI() != null && sibling.getNamespaceURI().equals(uri) && sibling.getLocalName().equals(nodeName)) { if (number == 0){ return (Element)sibling; } number--; } sibling = sibling.getNextSibling(); } return null; } /** * @param sibling * @param nodeName * @return nodes with the constrain */ public static Element[] selectDsNodes(Node sibling, String nodeName) { return selectNodes(sibling, Constants.SignatureSpecNS, nodeName); } /** * @param sibling * @param uri * @param nodeName * @return nodes with the constraint */ public static Element[] selectNodes(Node sibling, String uri, String nodeName) { List list = new ArrayList(); while (sibling != null) { if (sibling.getNamespaceURI() != null && sibling.getNamespaceURI().equals(uri) && sibling.getLocalName().equals(nodeName)) { list.add((Element)sibling); } sibling = sibling.getNextSibling(); } return list.toArray(new Element[list.size()]); } /** * @param signatureElement * @param inputSet * @return nodes with the constrain */ public static Set excludeNodeFromSet(Node signatureElement, Set inputSet) { Set resultSet = new HashSet(); Iterator iterator = inputSet.iterator(); while (iterator.hasNext()) { Node inputNode = iterator.next(); if (!XMLUtils.isDescendantOrSelf(signatureElement, inputNode)) { resultSet.add(inputNode); } } return resultSet; } /** * Method getStrFromNode * * @param xpathnode * @return the string for the node. */ public static String getStrFromNode(Node xpathnode) { if (xpathnode.getNodeType() == Node.TEXT_NODE) { // we iterate over all siblings of the context node because eventually, // the text is "polluted" with pi's or comments StringBuilder sb = new StringBuilder(); for (Node currentSibling = xpathnode.getParentNode().getFirstChild(); currentSibling != null; currentSibling = currentSibling.getNextSibling()) { if (currentSibling.getNodeType() == Node.TEXT_NODE) { sb.append(((Text) currentSibling).getData()); } } return sb.toString(); } else if (xpathnode.getNodeType() == Node.ATTRIBUTE_NODE) { return ((Attr) xpathnode).getNodeValue(); } else if (xpathnode.getNodeType() == Node.PROCESSING_INSTRUCTION_NODE) { return ((ProcessingInstruction) xpathnode).getNodeValue(); } return null; } /** * Returns true if the descendantOrSelf is on the descendant-or-self axis * of the context node. * * @param ctx * @param descendantOrSelf * @return true if the node is descendant */ public static boolean isDescendantOrSelf(Node ctx, Node descendantOrSelf) { if (ctx == descendantOrSelf) { return true; } Node parent = descendantOrSelf; while (true) { if (parent == null) { return false; } if (parent == ctx) { return true; } if (parent.getNodeType() == Node.ATTRIBUTE_NODE) { parent = ((Attr) parent).getOwnerElement(); } else { parent = parent.getParentNode(); } } } public static boolean ignoreLineBreaks() { return ignoreLineBreaks; } /** * Returns the attribute value for the attribute with the specified name. * Returns null if there is no such attribute, or * the empty string if the attribute value is empty. * *

This works around a limitation of the DOM * Element.getAttributeNode method, which does not distinguish * between an unspecified attribute and an attribute with a value of * "" (it returns "" for both cases). * * @param elem the element containing the attribute * @param name the name of the attribute * @return the attribute value (may be null if unspecified) */ public static String getAttributeValue(Element elem, String name) { Attr attr = elem.getAttributeNodeNS(null, name); return (attr == null) ? null : attr.getValue(); } /** * This method is a tree-search to help prevent against wrapping attacks. It checks that no * two Elements have ID Attributes that match the "value" argument, if this is the case then * "false" is returned. Note that a return value of "true" does not necessarily mean that * a matching Element has been found, just that no wrapping attack has been detected. */ public static boolean protectAgainstWrappingAttack(Node startNode, String value) { Node startParent = startNode.getParentNode(); Node processedNode = null; Element foundElement = null; String id = value.trim(); if (id.charAt(0) == '#') { id = id.substring(1); } while (startNode != null) { if (startNode.getNodeType() == Node.ELEMENT_NODE) { Element se = (Element) startNode; NamedNodeMap attributes = se.getAttributes(); if (attributes != null) { for (int i = 0; i < attributes.getLength(); i++) { Attr attr = (Attr)attributes.item(i); if (attr.isId() && id.equals(attr.getValue())) { if (foundElement == null) { // Continue searching to find duplicates foundElement = attr.getOwnerElement(); } else { log.debug("Multiple elements with the same 'Id' attribute value!"); return false; } } } } } processedNode = startNode; startNode = startNode.getFirstChild(); // no child, this node is done. if (startNode == null) { // close node processing, get sibling startNode = processedNode.getNextSibling(); } // no more siblings, get parent, all children // of parent are processed. while (startNode == null) { processedNode = processedNode.getParentNode(); if (processedNode == startParent) { return true; } // close parent node processing (processed node now) startNode = processedNode.getNextSibling(); } } return true; } /** * This method is a tree-search to help prevent against wrapping attacks. It checks that no other * Element than the given "knownElement" argument has an ID attribute that matches the "value" * argument, which is the ID value of "knownElement". If this is the case then "false" is returned. */ public static boolean protectAgainstWrappingAttack( Node startNode, Element knownElement, String value ) { Node startParent = startNode.getParentNode(); Node processedNode = null; String id = value.trim(); if (id.charAt(0) == '#') { id = id.substring(1); } while (startNode != null) { if (startNode.getNodeType() == Node.ELEMENT_NODE) { Element se = (Element) startNode; NamedNodeMap attributes = se.getAttributes(); if (attributes != null) { for (int i = 0; i < attributes.getLength(); i++) { Attr attr = (Attr)attributes.item(i); if (attr.isId() && id.equals(attr.getValue()) && se != knownElement) { log.debug("Multiple elements with the same 'Id' attribute value!"); return false; } } } } processedNode = startNode; startNode = startNode.getFirstChild(); // no child, this node is done. if (startNode == null) { // close node processing, get sibling startNode = processedNode.getNextSibling(); } // no more siblings, get parent, all children // of parent are processed. while (startNode == null) { processedNode = processedNode.getParentNode(); if (processedNode == startParent) { return true; } // close parent node processing (processed node now) startNode = processedNode.getNextSibling(); } } return true; } }





© 2015 - 2024 Weber Informatics LLC | Privacy Policy