org.apache.xml.security.c14n.Canonicalizer Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of xmlsec Show documentation
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: 4.0.3
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.c14n;

import java.io.ByteArrayInputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;

import javax.xml.XMLConstants;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;

import org.apache.xml.security.c14n.implementations.Canonicalizer11_OmitComments;
import org.apache.xml.security.c14n.implementations.Canonicalizer11_WithComments;
import org.apache.xml.security.c14n.implementations.Canonicalizer20010315ExclOmitComments;
import org.apache.xml.security.c14n.implementations.Canonicalizer20010315ExclWithComments;
import org.apache.xml.security.c14n.implementations.Canonicalizer20010315OmitComments;
import org.apache.xml.security.c14n.implementations.Canonicalizer20010315WithComments;
import org.apache.xml.security.exceptions.AlgorithmAlreadyRegisteredException;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;

/**
 *
 * @author Christian Geuer-Pollmann
 */
public class Canonicalizer {

    /** The output encoding of canonicalized data */
    public static final String ENCODING = "UTF8";

    /**
     * XPath Expression for selecting every node and continuous comments joined 
     * in only one node 
     */
    public static final String XPATH_C14N_WITH_COMMENTS_SINGLE_NODE = 
        "(.//. | .//@* | .//namespace::*)";

    /**
     * The URL defined in XML-SEC Rec for inclusive c14n without comments.
     */
    public static final String ALGO_ID_C14N_OMIT_COMMENTS = 
        "http://www.w3.org/TR/2001/REC-xml-c14n-20010315";
    /**
     * The URL defined in XML-SEC Rec for inclusive c14n with comments.
     */
    public static final String ALGO_ID_C14N_WITH_COMMENTS = 
        ALGO_ID_C14N_OMIT_COMMENTS + "#WithComments";
    /**
     * The URL defined in XML-SEC Rec for exclusive c14n without comments.
     */
    public static final String ALGO_ID_C14N_EXCL_OMIT_COMMENTS = 
        "http://www.w3.org/2001/10/xml-exc-c14n#";
    /**
     * The URL defined in XML-SEC Rec for exclusive c14n with comments.
     */
    public static final String ALGO_ID_C14N_EXCL_WITH_COMMENTS = 
        ALGO_ID_C14N_EXCL_OMIT_COMMENTS + "WithComments";
    /**
     * The URI for inclusive c14n 1.1 without comments.
     */
    public static final String ALGO_ID_C14N11_OMIT_COMMENTS = 
        "http://www.w3.org/2006/12/xml-c14n11";
    /**
     * The URI for inclusive c14n 1.1 with comments.
     */
    public static final String ALGO_ID_C14N11_WITH_COMMENTS = 
        ALGO_ID_C14N11_OMIT_COMMENTS + "#WithComments";

    private static Map> canonicalizerHash = 
        new ConcurrentHashMap>();
    
    private final CanonicalizerSpi canonicalizerSpi;
    
    /**
     * Constructor Canonicalizer
     *
     * @param algorithmURI
     * @throws InvalidCanonicalizerException
     */
    private Canonicalizer(String algorithmURI) throws InvalidCanonicalizerException {
        try {
            Class implementingClass = 
                canonicalizerHash.get(algorithmURI);

            canonicalizerSpi = implementingClass.newInstance();
            canonicalizerSpi.reset = true;
        } catch (Exception e) {
            Object exArgs[] = { algorithmURI };
            throw new InvalidCanonicalizerException(
                "signature.Canonicalizer.UnknownCanonicalizer", exArgs, e
            );
        }
    }

    /**
     * Method getInstance
     *
     * @param algorithmURI
     * @return a Canonicalizer instance ready for the job
     * @throws InvalidCanonicalizerException
     */
    public static final Canonicalizer getInstance(String algorithmURI)
        throws InvalidCanonicalizerException {
        return new Canonicalizer(algorithmURI);
    }

    /**
     * Method register
     *
     * @param algorithmURI
     * @param implementingClass
     * @throws AlgorithmAlreadyRegisteredException
     */
    @SuppressWarnings("unchecked")
    public static void register(String algorithmURI, String implementingClass)
        throws AlgorithmAlreadyRegisteredException, ClassNotFoundException {
        // check whether URI is already registered
        Class registeredClass = 
            canonicalizerHash.get(algorithmURI);

        if (registeredClass != null)  {
            Object exArgs[] = { algorithmURI, registeredClass };
            throw new AlgorithmAlreadyRegisteredException("algorithm.alreadyRegistered", exArgs);
        }

        canonicalizerHash.put(
            algorithmURI, (Class)Class.forName(implementingClass)
        );
    }
    
    /**
     * Method register
     *
     * @param algorithmURI
     * @param implementingClass
     * @throws AlgorithmAlreadyRegisteredException
     */
    public static void register(String algorithmURI, Class implementingClass)
        throws AlgorithmAlreadyRegisteredException, ClassNotFoundException {
        // check whether URI is already registered
        Class registeredClass = canonicalizerHash.get(algorithmURI);

        if (registeredClass != null)  {
            Object exArgs[] = { algorithmURI, registeredClass };
            throw new AlgorithmAlreadyRegisteredException("algorithm.alreadyRegistered", exArgs);
        }

        canonicalizerHash.put(algorithmURI, implementingClass);
    }
    
    /**
     * This method registers the default algorithms.
     */
    public static void registerDefaultAlgorithms() {
        canonicalizerHash.put(
            Canonicalizer.ALGO_ID_C14N_OMIT_COMMENTS, 
            Canonicalizer20010315OmitComments.class
        );
        canonicalizerHash.put(
            Canonicalizer.ALGO_ID_C14N_WITH_COMMENTS, 
            Canonicalizer20010315WithComments.class
        );
        canonicalizerHash.put(
            Canonicalizer.ALGO_ID_C14N_EXCL_OMIT_COMMENTS, 
            Canonicalizer20010315ExclOmitComments.class
        );
        canonicalizerHash.put(
            Canonicalizer.ALGO_ID_C14N_EXCL_WITH_COMMENTS, 
            Canonicalizer20010315ExclWithComments.class
        );
        canonicalizerHash.put(
            Canonicalizer.ALGO_ID_C14N11_OMIT_COMMENTS, 
            Canonicalizer11_OmitComments.class
        );
        canonicalizerHash.put(
            Canonicalizer.ALGO_ID_C14N11_WITH_COMMENTS, 
            Canonicalizer11_WithComments.class
        );
    }

    /**
     * Method getURI
     *
     * @return the URI defined for this c14n instance.
     */
    public final String getURI() {
        return canonicalizerSpi.engineGetURI();
    }

    /**
     * Method getIncludeComments
     *
     * @return true if the c14n respect the comments.
     */
    public boolean getIncludeComments() {
        return canonicalizerSpi.engineGetIncludeComments();
    }

    /**
     * This method tries to canonicalize the given bytes. It's possible to even
     * canonicalize non-wellformed sequences if they are well-formed after being
     * wrapped with a >a<...>/a<.
     *
     * @param inputBytes
     * @return the result of the canonicalization.
     * @throws CanonicalizationException
     * @throws java.io.IOException
     * @throws javax.xml.parsers.ParserConfigurationException
     * @throws org.xml.sax.SAXException
     */
    public byte[] canonicalize(byte[] inputBytes)
        throws javax.xml.parsers.ParserConfigurationException,
        java.io.IOException, org.xml.sax.SAXException, CanonicalizationException {
        InputStream bais = new ByteArrayInputStream(inputBytes);
        InputSource in = new InputSource(bais);
        DocumentBuilderFactory dfactory = DocumentBuilderFactory.newInstance();
        dfactory.setFeature(XMLConstants.FEATURE_SECURE_PROCESSING, Boolean.TRUE);

        dfactory.setNamespaceAware(true);

        // needs to validate for ID attribute normalization
        dfactory.setValidating(true);

        DocumentBuilder db = dfactory.newDocumentBuilder();

        /*
         * for some of the test vectors from the specification,
         * there has to be a validating parser for ID attributes, default
         * attribute values, NMTOKENS, etc.
         * Unfortunately, the test vectors do use different DTDs or
         * even no DTD. So Xerces 1.3.1 fires many warnings about using
         * ErrorHandlers.
         *
         * Text from the spec:
         *
         * The input octet stream MUST contain a well-formed XML document,
         * but the input need not be validated. However, the attribute
         * value normalization and entity reference resolution MUST be
         * performed in accordance with the behaviors of a validating
         * XML processor. As well, nodes for default attributes (declared
         * in the ATTLIST with an AttValue but not specified) are created
         * in each element. Thus, the declarations in the document type
         * declaration are used to help create the canonical form, even
         * though the document type declaration is not retained in the
         * canonical form.
         */
        db.setErrorHandler(new org.apache.xml.security.utils.IgnoreAllErrorHandler());

        Document document = db.parse(in);
        return this.canonicalizeSubtree(document);
    }

    /**
     * Canonicalizes the subtree rooted by node.
     *
     * @param node The node to canonicalize
     * @return the result of the c14n.
     *
     * @throws CanonicalizationException
     */
    public byte[] canonicalizeSubtree(Node node) throws CanonicalizationException {
        return canonicalizerSpi.engineCanonicalizeSubTree(node);
    }

    /**
     * Canonicalizes the subtree rooted by node.
     *
     * @param node
     * @param inclusiveNamespaces
     * @return the result of the c14n.
     * @throws CanonicalizationException
     */
    public byte[] canonicalizeSubtree(Node node, String inclusiveNamespaces)
        throws CanonicalizationException {
        return canonicalizerSpi.engineCanonicalizeSubTree(node, inclusiveNamespaces);
    }

    /**
     * Canonicalizes an XPath node set. The xpathNodeSet is treated
     * as a list of XPath nodes, not as a list of subtrees.
     *
     * @param xpathNodeSet
     * @return the result of the c14n.
     * @throws CanonicalizationException
     */
    public byte[] canonicalizeXPathNodeSet(NodeList xpathNodeSet)
        throws CanonicalizationException {
        return canonicalizerSpi.engineCanonicalizeXPathNodeSet(xpathNodeSet);
    }

    /**
     * Canonicalizes an XPath node set. The xpathNodeSet is treated
     * as a list of XPath nodes, not as a list of subtrees.
     *
     * @param xpathNodeSet
     * @param inclusiveNamespaces
     * @return the result of the c14n.
     * @throws CanonicalizationException
     */
    public byte[] canonicalizeXPathNodeSet(
        NodeList xpathNodeSet, String inclusiveNamespaces
    ) throws CanonicalizationException {
        return 
            canonicalizerSpi.engineCanonicalizeXPathNodeSet(xpathNodeSet, inclusiveNamespaces);
    } 

    /**
     * Canonicalizes an XPath node set.
     *
     * @param xpathNodeSet
     * @return the result of the c14n.
     * @throws CanonicalizationException
     */
    public byte[] canonicalizeXPathNodeSet(Set xpathNodeSet) 
        throws CanonicalizationException {
        return canonicalizerSpi.engineCanonicalizeXPathNodeSet(xpathNodeSet);
    }

    /**
     * Canonicalizes an XPath node set.
     *
     * @param xpathNodeSet
     * @param inclusiveNamespaces
     * @return the result of the c14n.
     * @throws CanonicalizationException
     */
    public byte[] canonicalizeXPathNodeSet(
        Set xpathNodeSet, String inclusiveNamespaces
    ) throws CanonicalizationException {
        return 
            canonicalizerSpi.engineCanonicalizeXPathNodeSet(xpathNodeSet, inclusiveNamespaces);
    }

    /**
     * Sets the writer where the canonicalization ends.  ByteArrayOutputStream 
     * if none is set.
     * @param os
     */
    public void setWriter(OutputStream os) {
        canonicalizerSpi.setWriter(os);
    }

    /**
     * Returns the name of the implementing {@link CanonicalizerSpi} class
     *
     * @return the name of the implementing {@link CanonicalizerSpi} class
     */
    public String getImplementingCanonicalizerClass() {
        return canonicalizerSpi.getClass().getName();
    }

    /**
     * Set the canonicalizer behaviour to not reset.
     */
    public void notReset() {
        canonicalizerSpi.reset = false;
    }
    
}