org.fcrepo.server.security.xacml.pdp.MelcoePDPImpl Maven / Gradle / Ivy

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/*
 * File: MelcoePDPImpl.java
 *
 * Copyright 2007 Macquarie E-Learning Centre Of Excellence
 *
 * 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 org.fcrepo.server.security.xacml.pdp;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.util.HashSet;
import java.util.Set;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.sun.xacml.Indenter;
import com.sun.xacml.PDP;
import com.sun.xacml.PDPConfig;
import com.sun.xacml.ParsingException;
import com.sun.xacml.ctx.RequestCtx;
import com.sun.xacml.ctx.ResponseCtx;
import com.sun.xacml.ctx.Result;

/**
 * This is an implementation of the MelcoePDP interface. It provides for the
 * evaluation of requests. It uses
 *
 * @author [email protected]
 */
public class MelcoePDPImpl
        implements MelcoePDP {

    private static final Logger logger =
            LoggerFactory.getLogger(MelcoePDPImpl.class);

    private final PDP m_pdp;

    public MelcoePDPImpl(PDPConfig pdpConfig)
            throws MelcoePDPException {
        m_pdp = new PDP(pdpConfig);

        logger.info("PDP Instantiated and initialised!");
    }

    /*
     * (non-Javadoc)
     * @see org.fcrepo.server.security.xacml.pdp.MelcoePDP#evaluate(java.lang.String)
     */
    @Override
    public String evaluate(String request) throws EvaluationException {
        logger.debug("evaluating request: {}", request);

        RequestCtx req = null;
        ByteArrayInputStream is = new ByteArrayInputStream(request.getBytes());

        try {
            req = RequestCtx.getInstance(is);
        } catch (ParsingException pe) {
            logger.error("Error parsing request:\n" + request, pe);
            throw new EvaluationException("Error parsing request:\n" + request);
        }

        ResponseCtx res = m_pdp.evaluate(req);
        ByteArrayOutputStream os = new ByteArrayOutputStream();
        res.encode(os, new Indenter());

        logger.debug("response is: {}", os.toString());

        return os.toString();
    }

    /*
     * (non-Javadoc)
     * @see org.fcrepo.server.security.xacml.pdp.MelcoePDP#evaluateBatch(java.lang.String[])
     */
    @Override
    public String evaluateBatch(String[] requests) throws EvaluationException {
            logger.debug("evaluating request batch");

        Set results = new HashSet();

        for (String req : requests) {
            ResponseCtx resCtx = null;
            String response = evaluate(req);
            ByteArrayInputStream is =
                    new ByteArrayInputStream(response.getBytes());
            try {
                resCtx = ResponseCtx.getInstance(is);
            } catch (ParsingException pe) {
                logger.error("Error parsing response:\n" + response, pe);
                throw new EvaluationException("Error parsing response:\n"
                        + response);
            }

            @SuppressWarnings("unchecked")
            Set r = resCtx.getResults();
            results.addAll(r);
        }

        ResponseCtx combinedResponse = new ResponseCtx(results);
        ByteArrayOutputStream os = new ByteArrayOutputStream();
        combinedResponse.encode(os, new Indenter());

        return os.toString();
    }

}