AttachmentResolver.java

/*
 * Copyright(c) 2002 Center for E-Commerce Infrastructure Development, The
 * University of Hong Kong (HKU). All Rights Reserved.
 *
 * This software is licensed under the Academic Free License Version 1.0
 *
 * Academic Free License
 * Version 1.0
 *
 * This Academic Free License applies to any software and associated 
 * documentation (the "Software") whose owner (the "Licensor") has placed the 
 * statement "Licensed under the Academic Free License Version 1.0" immediately 
 * after the copyright notice that applies to the Software. 
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy 
 * of the Software (1) to use, copy, modify, merge, publish, perform, 
 * distribute, sublicense, and/or sell copies of the Software, and to permit 
 * persons to whom the Software is furnished to do so, and (2) under patent 
 * claims owned or controlled by the Licensor that are embodied in the Software 
 * as furnished by the Licensor, to make, use, sell and offer for sale the 
 * Software and derivative works thereof, subject to the following conditions: 
 *
 * - Redistributions of the Software in source code form must retain all 
 *   copyright notices in the Software as furnished by the Licensor, this list 
 *   of conditions, and the following disclaimers. 
 * - Redistributions of the Software in executable form must reproduce all 
 *   copyright notices in the Software as furnished by the Licensor, this list 
 *   of conditions, and the following disclaimers in the documentation and/or 
 *   other materials provided with the distribution. 
 * - Neither the names of Licensor, nor the names of any contributors to the 
 *   Software, nor any of their trademarks or service marks, may be used to 
 *   endorse or promote products derived from this Software without express 
 *   prior written permission of the Licensor. 
 *
 * DISCLAIMERS: LICENSOR WARRANTS THAT THE COPYRIGHT IN AND TO THE SOFTWARE IS 
 * OWNED BY THE LICENSOR OR THAT THE SOFTWARE IS DISTRIBUTED BY LICENSOR UNDER 
 * A VALID CURRENT LICENSE. EXCEPT AS EXPRESSLY STATED IN THE IMMEDIATELY 
 * PRECEDING SENTENCE, THE SOFTWARE IS PROVIDED BY THE LICENSOR, CONTRIBUTORS 
 * AND COPYRIGHT OWNERS "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
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 * LICENSOR, CONTRIBUTORS OR COPYRIGHT OWNERS BE LIABLE FOR ANY CLAIM, DAMAGES 
 * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE. 
 *
 * This license is Copyright (C) 2002 Lawrence E. Rosen. All rights reserved. 
 * Permission is hereby granted to copy and distribute this license without 
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 */

/* ===== 
 *
 * $Header: /home/cvsroot/ebxml-pkg/src/hk/hku/cecid/ebms/pkg/AttachmentResolver.java,v 1.1 2005/07/28 09:36:24 dcmsze Exp $
 *
 * Code authored by:
 *
 * cyng [2002-03-21]
 *
 * Code reviewed by:
 *
 * username [YYYY-MM-DD]
 *
 * Remarks:
 *
 * =====
 */

package hk.hku.cecid.ebms.pkg;

import org.apache.xml.security.signature.XMLSignatureInput;
import org.apache.xml.security.utils.resolver.ResourceResolverException;
import org.apache.xml.security.utils.resolver.ResourceResolverSpi;
import org.w3c.dom.Attr;
/**
 * A <code>ResourceResolver</code> implementation used by Apache Security
 * library. The URI in the <code>Reference</code> element of a digital
 * signature points to some internal or external resources. This
 * <code>AttachmentResolver</code> is used to provide the resources in
 * the <code>EbxmlMessage</code> payload attachments and also the
 * <code>SOAPPart</code> itself with Reference URI="".
 *
 * @author cyng
 * @version $Revision: 1.1 $
 */
class AttachmentResolver extends ResourceResolverSpi {

    private final EbxmlMessage ebxmlMessage;

    AttachmentResolver(EbxmlMessage ebxmlMessage) {
        super();
        this.ebxmlMessage = ebxmlMessage;
    }

    public XMLSignatureInput engineResolve(Attr uri, String baseUri)
        throws ResourceResolverException {
        final String href = uri.getNodeValue();

        if (!href.startsWith(PayloadContainer.HREF_PREFIX)) {
            final Object exArgs[] = { "Reference URI does not start with "
                                      + PayloadContainer.HREF_PREFIX };
            throw new ResourceResolverException(href, exArgs, uri, baseUri);
        }

        final String contentId = href.substring(PayloadContainer.HREF_PREFIX.
                                                length());
        final PayloadContainer payload = ebxmlMessage.
            getPayloadContainer(contentId);
        if (payload == null) {
            final Object exArgs[] = { "Reference URI = " + href
                                      + " does not exist!" };
            throw new ResourceResolverException(href, exArgs, uri, baseUri);
        }
        final XMLSignatureInput input;
        try {
            input = new XMLSignatureInput(payload.getDataHandler().
                                          getInputStream());
        }
        catch (Exception e) {
            throw new ResourceResolverException(href, e, uri, baseUri);
        }
        input.setSourceURI(href);
        input.setMIMEType(payload.getContentType());

        return input;
    }

    public boolean engineCanResolve(Attr uri, String baseUri) {
        final String href = uri.getNodeValue();
        if (href.startsWith(PayloadContainer.HREF_PREFIX)) {
            final String contentId = href.substring(PayloadContainer.
                                                    HREF_PREFIX.length());
            final PayloadContainer payload = ebxmlMessage.
                getPayloadContainer(contentId);
            if (payload != null) {
                return true;
            }
        }
        return false;
    }
}