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 * Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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package com.sun.security.sasl.util;

import javax.security.sasl.Sasl;

import java.util.Map;

/**

 * Static class that contains utilities for dealing with Java SASL

 * security policy-related properties.

 *

 * @author Rosanna Lee

 */

final public class PolicyUtils {

    // Can't create one of these

    private PolicyUtils() {

    }

    public final static int NOPLAINTEXT = 0x0001;

    public final static int NOACTIVE = 0x0002;

    public final static int NODICTIONARY = 0x0004;

    public final static int FORWARD_SECRECY = 0x0008;

    public final static int NOANONYMOUS = 0x0010;

    public final static int PASS_CREDENTIALS = 0x0200;

    /**

     * Determines whether a mechanism's characteristics, as defined in flags,

     * fits the security policy properties found in props.

     * @param flags The mechanism's security characteristics

     * @param props The security policy properties to check

     * @return true if passes; false if fails

     */

    public static boolean checkPolicy(int flags, Map<String, ?> props) {

        if (props == null) {

            return true;

        }

        if ("true".equalsIgnoreCase((String)props.get(Sasl.POLICY_NOPLAINTEXT))

            && (flags&NOPLAINTEXT) == 0) {

            return false;

        }

        if ("true".equalsIgnoreCase((String)props.get(Sasl.POLICY_NOACTIVE))

            && (flags&NOACTIVE) == 0) {

            return false;

        }

        if ("true".equalsIgnoreCase((String)props.get(Sasl.POLICY_NODICTIONARY))

            && (flags&NODICTIONARY) == 0) {

            return false;

        }

        if ("true".equalsIgnoreCase((String)props.get(Sasl.POLICY_NOANONYMOUS))

            && (flags&NOANONYMOUS) == 0) {

            return false;

        }

        if ("true".equalsIgnoreCase((String)props.get(Sasl.POLICY_FORWARD_SECRECY))

            && (flags&FORWARD_SECRECY) == 0) {

            return false;

        }

        if ("true".equalsIgnoreCase((String)props.get(Sasl.POLICY_PASS_CREDENTIALS))

            && (flags&PASS_CREDENTIALS) == 0) {

            return false;

        }

        return true;

    }

    /**

     * Given a list of mechanisms and their characteristics, select the

     * subset that conforms to the policies defined in props.

     * Useful for SaslXXXFactory.getMechanismNames(props) implementations.

     *

     */

    public static String[] filterMechs(String[] mechs, int[] policies,

        Map<String, ?> props) {

        if (props == null) {

            return mechs.clone();

        }

        boolean[] passed = new boolean[mechs.length];

        int count = 0;

        for (int i = 0; i< mechs.length; i++) {

            if (passed[i] = checkPolicy(policies[i], props)) {

                ++count;

            }

        }

        String[] answer = new String[count];

        for (int i = 0, j=0; i< mechs.length; i++) {

            if (passed[i]) {

                answer[j++] = mechs[i];

            }

        }

        return answer;

    }

}