All Downloads are FREE. Search and download functionalities are using the official Maven repository.

org.osgi.service.remoteserviceadmin.EndpointPermission Maven / Gradle / Ivy

The newest version!
/*
 * Copyright (c) OSGi Alliance (2000, 2013). All Rights Reserved.
 *
 * 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.osgi.service.remoteserviceadmin;

import static org.osgi.service.remoteserviceadmin.RemoteConstants.*;
import java.io.IOException;
import java.io.NotSerializableException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.ObjectStreamField;
import java.security.Permission;
import java.security.PermissionCollection;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Dictionary;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.TreeMap;
import org.osgi.framework.Filter;
import org.osgi.framework.FrameworkUtil;
import org.osgi.framework.InvalidSyntaxException;

/**
 * A bundle's authority to export, import or read an Endpoint.
 * 
    *
  • The {@code export} action allows a bundle to export a service as an * Endpoint.
  • *
  • The {@code import} action allows a bundle to import a service from an * Endpoint.
  • *
  • The {@code read} action allows a bundle to read references to an * Endpoint.
  • *
* Permission to read an Endpoint is required in order to detect events * regarding an Endpoint. Untrusted bundles should not be able to detect the * presence of certain Endpoints unless they have the appropriate * {@code EndpointPermission} to read the specific service. * * @ThreadSafe * @author $Id: 60ecb3f4ed224d9dc02c95ee9ce4e4786b4ff126 $ */ public final class EndpointPermission extends Permission { static final long serialVersionUID = -7662148639076511574L; /** * The action string {@code read}. */ public final static String READ = "read"; /** * The action string {@code import}. The {@code import} action implies the * {@code read} action. */ public final static String IMPORT = "import"; /** * The action string {@code export}. The {@code export} action implies the * {@code read} action. */ public final static String EXPORT = "export"; private final static int ACTION_READ = 0x00000001; private final static int ACTION_IMPORT = 0x00000002; private final static int ACTION_EXPORT = 0x00000004; private final static int ACTION_ALL = ACTION_EXPORT | ACTION_IMPORT | ACTION_READ; final static int ACTION_NONE = 0; /** * The actions mask. */ transient int action_mask; /** * The actions in canonical form. * * @serial */ private volatile String actions = null; /** * The endpoint used by this EndpointPermission. Must be {@code null} if not * constructed with a endpoint. */ transient final EndpointDescription endpoint; /** * This dictionary holds the properties of the permission, used to match a * filter in implies. */ private transient final Dictionary properties; /** * If this EndpointPermission was not constructed with an * EndpointDescription, this holds a Filter matching object used to evaluate * the filter in implies or {@code null} for wildcard. */ transient Filter filter; /** * Create a new EndpointPermission with the specified filter. * *

* The filter will be evaluated against the endpoint properties of a * requested EndpointPermission. * *

* There are three possible actions: {@code read}, {@code import} and * {@code export}. The {@code read} action allows the owner of this * permission to see the presence of distributed services. The * {@code import} action allows the owner of this permission to import an * endpoint. The {@code export} action allows the owner of this permission * to export a service. * * @param filterString The filter string or "*" to match all * endpoints. * @param actions The actions {@code read}, {@code import}, or * {@code export}. * @throws IllegalArgumentException If the filter has an invalid syntax or * the actions are not valid. */ public EndpointPermission(String filterString, String actions) { this(filterString, parseActions(actions)); } /** * Creates a new requested {@code EndpointPermission} object to be used by * code that must perform {@code checkPermission}. * {@code EndpointPermission} objects created with this constructor cannot * be added to an {@code EndpointPermission} permission collection. * * @param endpoint The requested endpoint. * @param localFrameworkUUID The UUID of the local framework. This is used * to support matching the * {@link RemoteConstants#ENDPOINT_FRAMEWORK_UUID * endpoint.framework.uuid} endpoint property to the * {@code <>} value in the filter expression. * @param actions The actions {@code read}, {@code import}, or * {@code export}. * @throws IllegalArgumentException If the endpoint is {@code null} or the * actions are not valid. */ public EndpointPermission(EndpointDescription endpoint, String localFrameworkUUID, String actions) { super(createName(endpoint)); setTransients(null, parseActions(actions)); Map props; if ((localFrameworkUUID != null) && localFrameworkUUID.equals(endpoint.getFrameworkUUID())) { props = new TreeMap(String.CASE_INSENSITIVE_ORDER); props.putAll(endpoint.getProperties()); props.put(ENDPOINT_FRAMEWORK_UUID, new String[] {endpoint.getFrameworkUUID(), "<>"}); } else { props = endpoint.getProperties(); } this.endpoint = endpoint; this.properties = new EndpointDescription.UnmodifiableDictionary(props); } /** * Create a permission name from a EndpointDescription. * * @param endpoint EndpointDescription to use to create permission name. * @return permission name. */ private static String createName(EndpointDescription endpoint) { if (endpoint == null) { throw new IllegalArgumentException("invalid endpoint: null"); } StringBuffer sb = new StringBuffer("(" + ENDPOINT_ID + "="); sb.append(endpoint.getId()); sb.append(")"); return sb.toString(); } /** * Package private constructor used by EndpointPermissionCollection. * * @param name class name * @param mask action mask */ EndpointPermission(String name, int mask) { super(name); setTransients(parseFilter(name), mask); this.endpoint = null; this.properties = null; } /** * Called by constructors and when deserialized. * * @param mask action mask */ private void setTransients(Filter f, int mask) { if ((mask == ACTION_NONE) || ((mask & ACTION_ALL) != mask)) { throw new IllegalArgumentException("invalid action string"); } action_mask = mask; filter = f; } /** * Parse action string into action mask. * * @param actions Action string. * @return action mask. */ private static int parseActions(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 >= 5 && (a[i - 5] == 'i' || a[i - 5] == 'I') && (a[i - 4] == 'm' || a[i - 4] == 'M') && (a[i - 3] == 'p' || a[i - 3] == 'P') && (a[i - 2] == 'o' || a[i - 2] == 'O') && (a[i - 1] == 'r' || a[i - 1] == 'R') && (a[i] == 't' || a[i] == 'T')) { matchlen = 6; mask |= ACTION_IMPORT | ACTION_READ; } else if (i >= 5 && (a[i - 5] == 'e' || a[i - 5] == 'E') && (a[i - 4] == 'x' || a[i - 4] == 'X') && (a[i - 3] == 'p' || a[i - 3] == 'P') && (a[i - 2] == 'o' || a[i - 2] == 'O') && (a[i - 1] == 'r' || a[i - 1] == 'R') && (a[i] == 't' || a[i] == 'T')) { matchlen = 6; mask |= ACTION_EXPORT | ACTION_READ; } else { if (i >= 3 && (a[i - 3] == 'r' || a[i - 3] == 'R') && (a[i - 2] == 'e' || a[i - 2] == 'E') && (a[i - 1] == 'a' || a[i - 1] == 'A') && (a[i] == 'd' || a[i] == 'D')) { matchlen = 4; mask |= ACTION_READ; } else { // parse error throw new IllegalArgumentException("invalid permission: " + actions); } } // make sure we didn't just match the tail of a word // like "ackbarfread". 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; } /** * Parse filter string into a Filter object. * * @param filterString The filter string to parse. * @return a Filter for this bundle. * @throws IllegalArgumentException If the filter syntax is invalid. */ private static Filter parseFilter(String filterString) { if (filterString == null) { throw new IllegalArgumentException("invalid filter: null"); } filterString = filterString.trim(); if (filterString.equals("*")) { return null; // wildcard } try { return FrameworkUtil.createFilter(filterString); } catch (InvalidSyntaxException e) { IllegalArgumentException iae = new IllegalArgumentException("invalid filter"); iae.initCause(e); throw iae; } } /** * Determines if a {@code EndpointPermission} object "implies" the specified * permission. * * @param p The target permission to check. * @return {@code true} if the specified permission is implied by this * object; {@code false} otherwise. */ public boolean implies(Permission p) { if (!(p instanceof EndpointPermission)) { return false; } EndpointPermission requested = (EndpointPermission) p; if (endpoint != null) { return false; } // if requested permission has a filter, then it is an invalid argument if (requested.filter != null) { return false; } return implies0(requested, ACTION_NONE); } /** * Internal implies method. Used by the implies and the permission * collection implies methods. * * @param requested The requested EndpointPermission which has already be * validated as a proper argument. The requested EndpointPermission * must not have a filter expression. * @param effective The effective actions with which to start. * @return {@code true} if the specified permission is implied by this * object; {@code false} otherwise. */ boolean implies0(EndpointPermission requested, int effective) { /* check actions first - much faster */ effective |= action_mask; final int desired = requested.action_mask; if ((effective & desired) != desired) { return false; } /* if we have no filter */ Filter f = filter; if (f == null) { // it's "*" return true; } return f.matchCase(requested.getProperties()); } /** * Returns the canonical string representation of the actions. Always * returns present actions in the following canonical order: {@code read}, * {@code import}, {@code export}. * * @return The canonical string representation of the actions. */ public String getActions() { String result = actions; if (result == null) { StringBuffer sb = new StringBuffer(); boolean comma = false; int mask = action_mask; if ((mask & ACTION_READ) == ACTION_READ) { sb.append(READ); comma = true; } if ((mask & ACTION_IMPORT) == ACTION_IMPORT) { if (comma) sb.append(','); sb.append(IMPORT); } if ((mask & ACTION_EXPORT) == ACTION_EXPORT) { if (comma) sb.append(','); sb.append(EXPORT); } actions = result = sb.toString(); } return result; } /** * Returns a new {@code PermissionCollection} object for storing * {@code EndpointPermission} objects. * * @return A new {@code PermissionCollection} object suitable for storing * {@code EndpointPermission} objects. */ public PermissionCollection newPermissionCollection() { return new EndpointPermissionCollection(); } /** * Determines the equality of two EndpointPermission objects. * * Checks that specified object has the same name, actions and endpoint as * this {@code EndpointPermission}. * * @param obj The object to test for equality. * @return true If obj is a {@code EndpointPermission}, and has the same * name, actions and endpoint as this {@code EndpointPermission} * object; {@code false} otherwise. */ public boolean equals(Object obj) { if (obj == this) { return true; } if (!(obj instanceof EndpointPermission)) { return false; } EndpointPermission ep = (EndpointPermission) obj; return (action_mask == ep.action_mask) && getName().equals(ep.getName()) && ((endpoint == ep.endpoint) || ((endpoint != null) && (ep.endpoint != null) && endpoint.equals(ep.endpoint))); } /** * Returns the hash code value for this object. * * @return Hash code value for this object. */ public int hashCode() { int h = 31 * 17 + getName().hashCode(); h = 31 * h + getActions().hashCode(); if (endpoint != null) { h = 31 * h + endpoint.hashCode(); } return h; } /** * WriteObject is called to save the state of this permission to a stream. * The actions are serialized, and the superclass takes care of the name. */ private synchronized void writeObject(java.io.ObjectOutputStream s) throws IOException { if (endpoint != null) { throw new NotSerializableException("cannot serialize"); } // Write out the actions. The superclass takes care of the name // call getActions to make sure actions field is initialized if (actions == null) { getActions(); } s.defaultWriteObject(); } /** * readObject is called to restore the state of this permission from a * stream. */ private synchronized void readObject(java.io.ObjectInputStream s) throws IOException, ClassNotFoundException { // Read in the action, then initialize the rest s.defaultReadObject(); setTransients(parseFilter(getName()), parseActions(actions)); } /** * Called by {@link EndpointPermission#implies(Permission)}. * * @return a dictionary of properties for this permission. */ private Dictionary getProperties() { return properties; } } /** * Stores a set of EndpointPermission permissions. * * @see java.security.Permission * @see java.security.Permissions * @see java.security.PermissionCollection */ final class EndpointPermissionCollection extends PermissionCollection { static final long serialVersionUID = 662615640374640621L; /** * Table of permissions. * * @serial * @GuardedBy this */ private Map permissions; /** * Boolean saying if "*" is in the collection. * * @serial * @GuardedBy this */ private boolean all_allowed; /** * Creates an empty EndpointPermissions object. */ public EndpointPermissionCollection() { permissions = new HashMap(); all_allowed = false; } /** * Adds a permission to this permission collection. * * @param permission The Permission object to add. * @throws IllegalArgumentException If the specified permission is not a * EndpointPermission object. * @throws SecurityException If this {@code EndpointPermissionCollection} * object has been marked read-only. */ public void add(final Permission permission) { if (!(permission instanceof EndpointPermission)) { throw new IllegalArgumentException("invalid permission: " + permission); } if (isReadOnly()) { throw new SecurityException("attempt to add a Permission to a " + "readonly PermissionCollection"); } final EndpointPermission ep = (EndpointPermission) permission; if (ep.endpoint != null) { throw new IllegalArgumentException("cannot add to collection: " + ep); } final String name = ep.getName(); synchronized (this) { /* select the bucket for the permission */ Map pc = permissions; final EndpointPermission existing = pc.get(name); if (existing != null) { final int oldMask = existing.action_mask; final int newMask = ep.action_mask; if (oldMask != newMask) { pc.put(name, new EndpointPermission(name, oldMask | newMask)); } } else { pc.put(name, ep); } if (!all_allowed) { if (name.equals("*")) { all_allowed = true; } } } } /** * Determines if a set of permissions implies the permissions expressed in * {@code permission}. * * @param permission The Permission object to compare. * @return {@code true} if {@code permission} is a proper subset of a * permission in the set; {@code false} otherwise. */ public boolean implies(final Permission permission) { if (!(permission instanceof EndpointPermission)) { return false; } final EndpointPermission requested = (EndpointPermission) permission; /* if requested permission has a filter, then it is an invalid argument */ if (requested.filter != null) { return false; } int effective = EndpointPermission.ACTION_NONE; Collection perms; synchronized (this) { final int desired = requested.action_mask; /* short circuit if the "*" Permission was added */ if (all_allowed) { EndpointPermission ep = permissions.get("*"); if (ep != null) { effective |= ep.action_mask; if ((effective & desired) == desired) { return true; } } } perms = permissions.values(); } /* iterate one by one over permissions */ for (Iterator iter = perms.iterator(); iter.hasNext();) { if (iter.next().implies0(requested, effective)) { return true; } } return false; } /** * Returns an enumeration of all the {@code EndpointPermission} objects in * the container. * * @return Enumeration of all the EndpointPermission objects. */ public synchronized Enumeration elements() { List all = new ArrayList(permissions.values()); return Collections.enumeration(all); } /* serialization logic */ private static final ObjectStreamField[] serialPersistentFields = {new ObjectStreamField("permissions", HashMap.class), new ObjectStreamField("all_allowed", Boolean.TYPE)}; private synchronized void writeObject(ObjectOutputStream out) throws IOException { ObjectOutputStream.PutField pfields = out.putFields(); pfields.put("permissions", permissions); pfields.put("all_allowed", all_allowed); out.writeFields(); } private synchronized void readObject(java.io.ObjectInputStream in) throws IOException, ClassNotFoundException { ObjectInputStream.GetField gfields = in.readFields(); permissions = (HashMap) gfields.get("permissions", new HashMap()); all_allowed = gfields.get("all_allowed", false); } }





© 2015 - 2024 Weber Informatics LLC | Privacy Policy