useradminpermission.java

OSGI这是一个中间件,与UPNP齐名,是用于移植到嵌入式平台之上

/*
 * $Header: /home/wistrand/cvs/knopflerfish.org/osgi/bundles/useradmin/src/org/osgi/service/useradmin/UserAdminPermission.java,v 1.1.1.1 2004/03/05 20:35:16 wistrand Exp $
 *
 * Copyright (c) The Open Services Gateway Initiative (2001, 2002).
 * All Rights Reserved.
 *
 * Implementation of certain elements of the Open Services Gateway Initiative
 * (OSGI) Specification may be subject to third party intellectual property
 * rights, including without limitation, patent rights (such a third party may
 * or may not be a member of OSGi). OSGi is not responsible and shall not be
 * held responsible in any manner for identifying or failing to identify any or
 * all such third party intellectual property rights.
 *
 * This document and the information contained herein are provided on an "AS
 * IS" basis and OSGI DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
 * BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL
 * NOT INFRINGE ANY RIGHTS AND ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR
 * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT WILL OSGI BE LIABLE FOR ANY
 * LOSS OF PROFITS, LOSS OF BUSINESS, LOSS OF USE OF DATA, INTERRUPTION OF
 * BUSINESS, OR FOR DIRECT, INDIRECT, SPECIAL OR EXEMPLARY, INCIDENTIAL,
 * PUNITIVE OR CONSEQUENTIAL DAMAGES OF ANY KIND IN CONNECTION WITH THIS
 * DOCUMENT OR THE INFORMATION CONTAINED HEREIN, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH LOSS OR DAMAGE.
 *
 * All Company, brand and product names may be trademarks that are the sole
 * property of their respective owners. All rights reserved.
 */

package org.osgi.service.useradmin;

import java.io.IOException;
import java.security.BasicPermission;
import java.security.Permission;
import java.security.PermissionCollection;
import java.util.Enumeration;
import java.util.Hashtable;

/**
 * Permission to configure and access the {@link Role} objects managed by a User
 * Admin service.
 * 
 * <p>
 * This class represents access to the <tt>Role</tt> objects managed by a User
 * Admin service and their properties and credentials (in the case of
 * {@link User} objects).
 * <p>
 * The permission name is the name (or name prefix) of a property or credential.
 * The naming convention follows the hierarchical property naming convention.
 * Also, an asterisk may appear at the end of the name, following a
 * &quot;.&quot;, or by itself, to signify a wildcard match. For example:
 * &quot;org.osgi.security.protocol.*&quot; or &quot;*&quot; is valid, but
 * &quot;*protocol&quot; or &quot;a*b&quot; are not valid.
 * 
 * <p>
 * The <tt>UserAdminPermission</tt> with the reserved name &quot;admin&quot;
 * represents the permission required for creating and removing <tt>Role</tt>
 * objects in the User Admin service, as well as adding and removing members in
 * a <tt>Group</tt> object. This <tt>UserAdminPermission</tt> does not have
 * any actions associated with it.
 * 
 * <p>
 * The actions to be granted are passed to the constructor in a string
 * containing a list of one or more comma-separated keywords. The possible
 * keywords are: <tt>changeProperty</tt>, <tt>changeCredential</tt>, and
 * <tt>getCredential</tt>. Their meaning is defined as follows:
 * 
 * <pre>
 *    action
 *    changeProperty    Permission to change (i.e., add and remove) 
 *                      Role object properties whose names start with
 *                      the name argument specified in the constructor.
 *    changeCredential  Permission to change (i.e., add and remove) 
 *                      User object credentials whose names start 
 *                      with the name argument specified in the constructor.
 *    getCredential     Permission to retrieve and check for the 
 *                      existence of User object credentials whose names 
 *                      start with the name argument specified in the 
 *                      constructor.
 * </pre>
 * 
 * The action string is converted to lowercase before processing.
 * 
 * <p>
 * Following is a PermissionInfo style policy entry which grants a user
 * administration bundle a number of <tt>UserAdminPermission</tt> object:
 * 
 * <pre>
 *    (org.osgi.service.useradmin.UserAdminPermission &quot;admin&quot;)
 *    (org.osgi.service.useradmin.UserAdminPermission &quot;com.foo.*&quot; &quot;changeProperty,getCredential,changeCredential&quot;)
 *    (org.osgi.service.useradmin.UserAdminPermission &quot;user.*&quot;, &quot;changeProperty,changeCredential&quot;)
 * </pre>
 * 
 * The first permission statement grants the bundle the permission to perform
 * any User Admin service operations of type "admin", that is, create and remove
 * roles and configure <tt>Group</tt> objects.
 * 
 * <p>
 * The second permission statement grants the bundle the permission to change
 * any properties as well as get and change any credentials whose names start
 * with <tt>com.foo.</tt>.
 * 
 * <p>
 * The third permission statement grants the bundle the permission to change any
 * properties and credentials whose names start with <tt>user.</tt>. This
 * means that the bundle is allowed to change, but not retrieve any credentials
 * with the given prefix.
 * 
 * <p>
 * The following policy entry empowers the Http Service bundle to perform user
 * authentication:
 * 
 * <pre>
 *    grant codeBase &quot;${jars}http.jar&quot; {
 *      permission org.osgi.service.useradmin.UserAdminPermission
 *        &quot;user.password&quot;, &quot;getCredential&quot;;
 *    };
 * </pre>
 * 
 * <p>
 * The permission statement grants the Http Service bundle the permission to
 * validate any password credentials (for authentication purposes), but the
 * bundle is not allowed to change any properties or credentials.
 * 
 * @version $Revision: 1.1.1.1 $
 * @author Open Services Gateway Initiative
 */

public final class UserAdminPermission extends BasicPermission {
    private static final long serialVersionUID = 1L;

    /**
     * The permission name &quot;admin&quot;.
     */
    public static final String ADMIN = "admin";

    /**
     * The action string &quot;changeProperty&quot;.
     */
    public static final String CHANGE_PROPERTY = "changeProperty";

    private static final int ACTION_CHANGE_PROPERTY = 0x1;

    /**
     * The action string &quot;changeCredential&quot;.
     */
    public static final String CHANGE_CREDENTIAL = "changeCredential";

    private static final int ACTION_CHANGE_CREDENTIAL = 0x2;

    /**
     * The action string &quot;getCredential&quot;.
     */
    public static final String GET_CREDENTIAL = "getCredential";

    private static final int ACTION_GET_CREDENTIAL = 0x4;

    /**
     * All actions
     */
    private static final int ACTION_ALL = ACTION_CHANGE_PROPERTY
            | ACTION_CHANGE_CREDENTIAL | ACTION_GET_CREDENTIAL;

    /**
     * No actions.
     */
    static final int ACTION_NONE = 0x0;

    /**
     * The actions in canonical form.
     * 
     * @serial
     */
    private String actions = null;

    /**
     * The actions mask.
     */
    private transient int action_mask = ACTION_NONE;

    /* Description of this <tt>UserAdminPermission</tt> (returned by <tt>toString</tt>) */
    private transient String description;

    /**
     * Creates a new <tt>UserAdminPermission</tt> with the specified name and
     * actions. <tt>name</tt> is either the reserved string &quot;admin&quot;
     * or the name of a credential or property, and <tt>actions</tt> contains
     * a comma-separated list of the actions granted on the specified name.
     * Valid actions are <tt>changeProperty</tt>, <tt>changeCredential</tt>,
     * and getCredential.
     * 
     * @param name
     *            the name of this <tt>UserAdminPermission</tt>
     * @param actions
     *            the action string.
     * 
     * @throws IllegalArgumentException
     *             If <tt>name</tt> equals &quot;admin&quot; and
     *             <tt>actions</tt> are specified.
     */
    public UserAdminPermission(String name, String actions) {
        this(name, getMask(actions));
    }

    /**
     * Package private constructor used by
     * <tt>UserAdminPermissionCollection</tt>.
     * 
     * @param name
     *            class name
     * @param action
     *            mask
     */
    UserAdminPermission(String name, int mask) {
        super(name);
        init(mask);
    }

    /**
     * Called by constructors and when deserialized.
     * 
     * @param action
     *            mask
     */
    private void init(int mask) {
        if (getName().equals(ADMIN)) {
            if (mask != ACTION_NONE) {
                throw new IllegalArgumentException("Actions specified for "
                        + "no-action " + "UserAdminPermission");
            }
        } else {
            if ((mask == ACTION_NONE) || ((mask & ACTION_ALL) != mask)) {
                throw new IllegalArgumentException("Invalid action string");
            }
        }
        action_mask = mask;
    }

    /**
     * Parses the action string into the action mask.
     * 
     * @param actions
     *            Action string.
     * @return action mask.
     */
    private static int getMask(String actions) {
        boolean seencomma = false;

        int mask = ACTION_NONE;

        if (actions == null) {
            return (mask);
        }

        char[] a = actions.toCharArray();

        int i = a.length - 1;
        if (i < 0)
            return (mask);

        while (i != -1) {
            char c;

            // skip whitespace
            while ((i != -1)
                    && ((c = a[i]) == ' ' || c == '\r' || c == '\n'
                            || c == '\f' || c == '\t'))
                i--;

            // check for the known strings
            int matchlen;

            if (i >= 12 && match_get(a, i - 10) && match_credential(a, i)) {
                matchlen = 13;
                mask |= ACTION_GET_CREDENTIAL;

            } else if (i >= 13 && match_change(a, i - 8)
                    && match_property(a, i)) {
                matchlen = 14;
                mask |= ACTION_CHANGE_PROPERTY;

            } else if (i >= 15 && match_change(a, i - 10)
                    && match_credential(a, i)) {
                matchlen = 16;
                mask |= ACTION_CHANGE_CREDENTIAL;

            } else {
                // parse error
                throw new IllegalArgumentException("invalid permission: "
                        + actions);
            }

            // make sure we didn't just match the tail of a word
            // like "ackbarfimport". Also, skip to the comma.
            seencomma = false;
            while (i >= matchlen && !seencomma) {
                switch (a[i - matchlen]) {
                case ',':
                    seencomma = true;
                /* FALLTHROUGH */
                case ' ':
                case '\r':
                case '\n':
                case '\f':
                case '\t':
                    break;
                default:
                    throw new IllegalArgumentException("invalid permission: "
                            + actions);
                }
                i--;
            }

            // point i at the location of the comma minus one (or -1).
            i -= matchlen;
        }

        if (seencomma) {
            throw new IllegalArgumentException("invalid permission: " + actions);
        }

        return (mask);
    }

    private static boolean match_change(char[] a, int i) {
        return ((a[i - 5] == 'c' || a[i - 5] == 'C')
                && (a[i - 4] == 'h' || a[i - 4] == 'H')
                && (a[i - 3] == 'a' || a[i - 3] == 'A')
                && (a[i - 2] == 'n' || a[i - 2] == 'N')
                && (a[i - 1] == 'g' || a[i - 1] == 'G') && (a[i - 0] == 'e' || a[i - 0] == 'E'));
    }

    private static boolean match_get(char[] a, int i) {
        return ((a[i - 2] == 'g' || a[i - 2] == 'G')
                && (a[i - 1] == 'e' || a[i - 1] == 'E') && (a[i - 0] == 't' || a[i - 0] == 'T'));
    }

    private static boolean match_property(char[] a, int i) {
        return ((a[i - 7] == 'p' || a[i - 7] == 'P')
                && (a[i - 6] == 'r' || a[i - 6] == 'R')
                && (a[i - 5] == 'o' || a[i - 5] == 'O')
                && (a[i - 4] == 'p' || a[i - 4] == 'P')
                && (a[i - 3] == 'e' || a[i - 3] == 'E')
                && (a[i - 2] == 'r' || a[i - 2] == 'R')
                && (a[i - 1] == 't' || a[i - 1] == 'T') && (a[i - 0] == 'y' || a[i - 0] == 'Y'));
    }