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 * reserved comment block

 * DO NOT REMOVE OR ALTER!

 */

/*

 * Copyright  1999-2004 The Apache Software Foundation.

 *

 *  Licensed 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 com.sun.org.apache.xml.internal.security.signature;

import java.io.ByteArrayInputStream;

import java.io.IOException;

import java.io.OutputStream;

import javax.crypto.SecretKey;

import javax.crypto.spec.SecretKeySpec;

import javax.xml.parsers.ParserConfigurationException;

import com.sun.org.apache.xml.internal.security.algorithms.SignatureAlgorithm;

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

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

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

import com.sun.org.apache.xml.internal.security.exceptions.XMLSecurityException;

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

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

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

import org.w3c.dom.Document;

import org.w3c.dom.Element;

import org.w3c.dom.Node;

import org.xml.sax.SAXException;

/**

 * Handles <code>&lt;ds:SignedInfo&gt;</code> elements

 * This <code>SignedInfo<code> element includes the canonicalization algorithm,

 * a signature algorithm, and one or more references.

 *

 * @author Christian Geuer-Pollmann

 */

public class SignedInfo extends Manifest {

    /** Field _signatureAlgorithm */

    private SignatureAlgorithm _signatureAlgorithm = null;

    /** Field _c14nizedBytes           */

    private byte[] _c14nizedBytes = null;

    private Element c14nMethod;

    private Element signatureMethod;

    /**

     * Overwrites {@link Manifest#addDocument} because it creates another

     * Element.

     *

     * @param doc the {@link Document} in which <code>XMLsignature</code> will

     *    be placed

     * @throws XMLSecurityException

     */

    public SignedInfo(Document doc) throws XMLSecurityException {

        this(doc, XMLSignature.ALGO_ID_SIGNATURE_DSA,

             Canonicalizer.ALGO_ID_C14N_OMIT_COMMENTS);

    }

    /**

     * Constructs {@link SignedInfo} using given Canonicalization algorithm and

     * Signature algorithm.

     *

     * @param doc <code>SignedInfo</code> is placed in this document

     * @param signatureMethodURI URI representation of the Digest and

     *    Signature algorithm

     * @param canonicalizationMethodURI URI representation of the

     *    Canonicalization method

     * @throws XMLSecurityException

     */

    public SignedInfo(Document doc, String signatureMethodURI,

        String canonicalizationMethodURI)

              throws XMLSecurityException {

        this(doc, signatureMethodURI, 0, canonicalizationMethodURI);

    }

    /**

     * Constructor SignedInfo

     *

     * @param doc <code>SignedInfo</code> is placed in this document

     * @param signatureMethodURI URI representation of the Digest and

     *    Signature algorithm

     * @param hMACOutputLength

     * @param canonicalizationMethodURI URI representation of the

     *    Canonicalization method

     * @throws XMLSecurityException

     */

    public SignedInfo(Document doc, String signatureMethodURI,

        int hMACOutputLength, String canonicalizationMethodURI)

              throws XMLSecurityException {

        super(doc);

        c14nMethod = XMLUtils.createElementInSignatureSpace(this._doc,

                                Constants._TAG_CANONICALIZATIONMETHOD);

        c14nMethod.setAttributeNS(null, Constants._ATT_ALGORITHM,

                                  canonicalizationMethodURI);

        this._constructionElement.appendChild(c14nMethod);

        XMLUtils.addReturnToElement(this._constructionElement);

        if (hMACOutputLength > 0) {

            this._signatureAlgorithm = new SignatureAlgorithm(this._doc,

                    signatureMethodURI, hMACOutputLength);

        } else {

            this._signatureAlgorithm = new SignatureAlgorithm(this._doc,

                    signatureMethodURI);

        }

        signatureMethod = this._signatureAlgorithm.getElement();

        this._constructionElement.appendChild(signatureMethod);

        XMLUtils.addReturnToElement(this._constructionElement);

    }

    /**

     * @param doc

     * @param signatureMethodElem

     * @param canonicalizationMethodElem

     * @throws XMLSecurityException

     */

    public SignedInfo(Document doc, Element signatureMethodElem,

        Element canonicalizationMethodElem) throws XMLSecurityException {

        super(doc);

        // Check this?

        this.c14nMethod = canonicalizationMethodElem;

        this._constructionElement.appendChild(c14nMethod);

        XMLUtils.addReturnToElement(this._constructionElement);

        this._signatureAlgorithm =

            new SignatureAlgorithm(signatureMethodElem, null);

        signatureMethod = this._signatureAlgorithm.getElement();

        this._constructionElement.appendChild(signatureMethod);

        XMLUtils.addReturnToElement(this._constructionElement);

    }

    /**

     * Build a {@link SignedInfo} from an {@link Element}

     *

     * @param element <code>SignedInfo</code>

     * @param baseURI the URI of the resource where the XML instance was stored

     * @throws XMLSecurityException

     * @see <A HREF="http://lists.w3.org/Archives/Public/w3c-ietf-xmldsig/2001OctDec/0033.html">Question</A>

     * @see <A HREF="http://lists.w3.org/Archives/Public/w3c-ietf-xmldsig/2001OctDec/0054.html">Answer</A>

     */

    public SignedInfo(Element element, String baseURI)

           throws XMLSecurityException {

        // Parse the Reference children and Id attribute in the Manifest

        super(element, baseURI);

        /* canonicalize ds:SignedInfo, reparse it into a new document

         * and replace the original not-canonicalized ds:SignedInfo by

         * the re-parsed canonicalized one.

         */

        c14nMethod = XMLUtils.getNextElement(element.getFirstChild());

        String c14nMethodURI = this.getCanonicalizationMethodURI();

        if (!(c14nMethodURI.equals(Canonicalizer.ALGO_ID_C14N_OMIT_COMMENTS) ||

              c14nMethodURI.equals(Canonicalizer.ALGO_ID_C14N_WITH_COMMENTS) ||

              c14nMethodURI.equals(Canonicalizer.ALGO_ID_C14N_EXCL_OMIT_COMMENTS) ||

              c14nMethodURI.equals(Canonicalizer.ALGO_ID_C14N_EXCL_WITH_COMMENTS))) {

            // the c14n is not a secure one and can rewrite the URIs or like

            // that reparse the SignedInfo to be sure

            try {

                Canonicalizer c14nizer =

                Canonicalizer.getInstance(this.getCanonicalizationMethodURI());

                this._c14nizedBytes =

                    c14nizer.canonicalizeSubtree(this._constructionElement);

                javax.xml.parsers.DocumentBuilderFactory dbf =

                    javax.xml.parsers.DocumentBuilderFactory.newInstance();

                dbf.setNamespaceAware(true);

                javax.xml.parsers.DocumentBuilder db = dbf.newDocumentBuilder();

                    db.parse(new ByteArrayInputStream(this._c14nizedBytes));

                Node imported =

                    this._doc.importNode(newdoc.getDocumentElement(), true);

                this._constructionElement.getParentNode().replaceChild(imported,

                    this._constructionElement);

                this._constructionElement = (Element) imported;

            } catch (ParserConfigurationException ex) {

                throw new XMLSecurityException("empty", ex);

            } catch (IOException ex) {

                throw new XMLSecurityException("empty", ex);

            } catch (SAXException ex) {

                throw new XMLSecurityException("empty", ex);

            }

        }

        signatureMethod = XMLUtils.getNextElement(c14nMethod.getNextSibling());

        this._signatureAlgorithm =

            new SignatureAlgorithm(signatureMethod, this.getBaseURI());

    }

   /**

    * Tests core validation process

    *

    * @return true if verification was successful

    * @throws MissingResourceFailureException

    * @throws XMLSecurityException

    */

   public boolean verify()

           throws MissingResourceFailureException, XMLSecurityException {

      return super.verifyReferences(false);

   }

   /**

    * Tests core validation process

    *

    * @param followManifests defines whether the verification process has to verify referenced <CODE>ds:Manifest</CODE>s, too

    * @return true if verification was successful

    * @throws MissingResourceFailureException

    * @throws XMLSecurityException

    */

   public boolean verify(boolean followManifests)

           throws MissingResourceFailureException, XMLSecurityException {

      return super.verifyReferences(followManifests);

   }

   /**

    * Returns getCanonicalizedOctetStream

    *

    * @return the canonicalization result octedt stream of <code>SignedInfo</code> element

    * @throws CanonicalizationException

    * @throws InvalidCanonicalizerException

    * @throws XMLSecurityException

    */

   public byte[] getCanonicalizedOctetStream()

           throws CanonicalizationException, InvalidCanonicalizerException,

                 XMLSecurityException {

      if ((this._c14nizedBytes == null)

              /*&& (this._state == ElementProxy.MODE_SIGN)*/) {

         Canonicalizer c14nizer =

            Canonicalizer.getInstance(this.getCanonicalizationMethodURI());

         this._c14nizedBytes =

            c14nizer.canonicalizeSubtree(this._constructionElement);

      }

      // make defensive copy

      byte[] output = new byte[this._c14nizedBytes.length];

      System.arraycopy(this._c14nizedBytes, 0, output, 0, output.length);

      return output;

   }

   /**

    *  Output the C14n stream to the give outputstream.

    * @param os

    * @throws CanonicalizationException

    * @throws InvalidCanonicalizerException

    * @throws XMLSecurityException

    */

   public void signInOctectStream(OutputStream os)

       throws CanonicalizationException, InvalidCanonicalizerException,

           XMLSecurityException {

        if ((this._c14nizedBytes == null)) {

       Canonicalizer c14nizer =

          Canonicalizer.getInstance(this.getCanonicalizationMethodURI());

       c14nizer.setWriter(os);

       String inclusiveNamespaces = this.getInclusiveNamespaces();

       if(inclusiveNamespaces == null)

        c14nizer.canonicalizeSubtree(this._constructionElement);

       else

        c14nizer.canonicalizeSubtree(this._constructionElement, inclusiveNamespaces);

    } else {

        try {

                        os.write(this._c14nizedBytes);

                } catch (IOException e) {

                        throw new RuntimeException(""+e);

                }

    }

   }

   /**

    * Returns the Canonicalization method URI

    *

    * @return the Canonicalization method URI

    */

   public String getCanonicalizationMethodURI() {

     return c14nMethod.getAttributeNS(null, Constants._ATT_ALGORITHM);

   }

   /**

    * Returns the Signature method URI

    *

    * @return the Signature method URI

    */

   public String getSignatureMethodURI() {

      Element signatureElement = this.getSignatureMethodElement();

      if (signatureElement != null) {

         return signatureElement.getAttributeNS(null, Constants._ATT_ALGORITHM);

      }

      return null;

   }

   /**

    * Method getSignatureMethodElement

    * @return gets The SignatureMethod Node.

    *

    */

   public Element getSignatureMethodElement() {

           return signatureMethod;

   }

   /**

    * Creates a SecretKey for the appropriate Mac algorithm based on a

    * byte[] array password.

    *

    * @param secretKeyBytes

    * @return the secret key for the SignedInfo element.

    */

   public SecretKey createSecretKey(byte[] secretKeyBytes)

   {

      return new SecretKeySpec(secretKeyBytes,

                               this._signatureAlgorithm

                                  .getJCEAlgorithmString());

   }

   protected SignatureAlgorithm getSignatureAlgorithm() {

           return _signatureAlgorithm;

   }

   /**

    * Method getBaseLocalName

    * @inheritDoc

    *

    */

   public String getBaseLocalName() {

      return Constants._TAG_SIGNEDINFO;

   }

   public String getInclusiveNamespaces() {

     String c14nMethodURI = c14nMethod.getAttributeNS(null, Constants._ATT_ALGORITHM);

     if(!(c14nMethodURI.equals("http://www.w3.org/2001/10/xml-exc-c14n#") ||

                        c14nMethodURI.equals("http://www.w3.org/2001/10/xml-exc-c14n#WithComments"))) {

                return null;

            }

     Element inclusiveElement = XMLUtils.getNextElement(

                 c14nMethod.getFirstChild());

     if(inclusiveElement != null)

     {

         try

         {

             String inclusiveNamespaces = new InclusiveNamespaces(inclusiveElement,

                         InclusiveNamespaces.ExclusiveCanonicalizationNamespace).getInclusiveNamespaces();

             return inclusiveNamespaces;

         }

         catch (XMLSecurityException e)

         {

             return null;

         }

     }

     return null;

    }

}