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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;

   /**

    * 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 Canoicaliztion algorithm and Signature algorithm

    *

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

    * @param CanonicalizationMethodURI URI representation of the Canonicalization method

    * @param SignatureMethodURI URI representation of the Digest and Signature algorithm

    * @throws XMLSecurityException

    */

   public SignedInfo(

           Document doc, String SignatureMethodURI, String CanonicalizationMethodURI)

              throws XMLSecurityException {

      this(doc, SignatureMethodURI, 0, CanonicalizationMethodURI);

   }

   /**

    * Constructor SignedInfo

    *

    * @param doc

    * @param CanonicalizationMethodURI

    * @param SignatureMethodURI

    * @param HMACOutputLength

    * @throws XMLSecurityException

    */

   public SignedInfo(

           Document doc, String SignatureMethodURI, int HMACOutputLength, String CanonicalizationMethodURI)

              throws XMLSecurityException {

      super(doc);

      // XMLUtils.addReturnToElement(this._constructionElement);

      {

         Element canonElem = XMLUtils.createElementInSignatureSpace(this._doc,

                                Constants._TAG_CANONICALIZATIONMETHOD);

         canonElem.setAttributeNS(null, Constants._ATT_ALGORITHM,

                                CanonicalizationMethodURI);

         this._constructionElement.appendChild(canonElem);

         XMLUtils.addReturnToElement(this._constructionElement);

      }

      {

         if (HMACOutputLength > 0) {

            this._signatureAlgorithm = new SignatureAlgorithm(this._doc,

                    SignatureMethodURI, HMACOutputLength);

         } else {

            this._signatureAlgorithm = new SignatureAlgorithm(this._doc,

                    SignatureMethodURI);

         }

         this._constructionElement

            .appendChild(this._signatureAlgorithm.getElement());

         XMLUtils.addReturnToElement(this._constructionElement);

      }

   }

   /**

    * @param doc

    * @param SignatureMethodElem

    * @param CanonicalizationMethodElem

    * @throws XMLSecurityException

    */

   public SignedInfo(

           Document doc, Element SignatureMethodElem, Element CanonicalizationMethodElem)

              throws XMLSecurityException {

      super(doc);

      this._constructionElement.appendChild(CanonicalizationMethodElem);

      XMLUtils.addReturnToElement(this._constructionElement);

      this._signatureAlgorithm = new SignatureAlgorithm(SignatureMethodElem, null);

      this._constructionElement

         .appendChild(this._signatureAlgorithm.getElement());

      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.

       */

      String c14nMethodURI=this.getCanonicalizationMethodURI();

     if (!(c14nMethodURI.equals("http://www.w3.org/TR/2001/REC-xml-c14n-20010315") ||

                c14nMethodURI.equals("http://www.w3.org/TR/2001/REC-xml-c14n-20010315#WithComments") ||

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

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

        //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();

         org.w3c.dom.Document newdoc =

            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);

      }

      }

      this._signatureAlgorithm =

         new SignatureAlgorithm(this.getSignatureMethodElement(),

                                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() {

    Element el= XMLUtils.selectDsNode(this._constructionElement.getFirstChild(),

     Constants._TAG_CANONICALIZATIONMETHOD,0);

     if (el==null) {

        return null;

     }

     return el.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 XMLUtils.selectDsNode(this._constructionElement.getFirstChild(),

        Constants._TAG_SIGNATUREMETHOD,0);

   }

   /**

    * 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());

   }

   /**

    * Method getBaseLocalName

    * @inheritDoc

    *

    */

   public String getBaseLocalName() {

      return Constants._TAG_SIGNEDINFO;

   }

   public String getInclusiveNamespaces() {

    Element el= XMLUtils.selectDsNode(this._constructionElement.getFirstChild(),

     Constants._TAG_CANONICALIZATIONMETHOD,0);

     if (el==null) {

        return null;

     }

     String c14nMethodURI = el.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.selectNode(

             el.getFirstChild(),InclusiveNamespaces.ExclusiveCanonicalizationNamespace,

        InclusiveNamespaces._TAG_EC_INCLUSIVENAMESPACES,0);

     if(inclusiveElement != null)

     {

         try

         {

             String inclusiveNamespaces = new InclusiveNamespaces(inclusiveElement,

                         InclusiveNamespaces.ExclusiveCanonicalizationNamespace).getInclusiveNamespaces();

             return inclusiveNamespaces;

         }

         catch (XMLSecurityException e)

         {

             return null;

         }

     }

     return null;

    }

}