| /* |
| * $Header: /cvshome/build/org.osgi.framework/src/org/osgi/framework/ServicePermission.java,v 1.15 2007/02/20 00:06:02 hargrave Exp $ |
| * |
| * Copyright (c) OSGi Alliance (2000, 2007). 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.framework; |
| |
| import java.io.IOException; |
| import java.security.*; |
| import java.util.Enumeration; |
| import java.util.Hashtable; |
| |
| /** |
| * A bundle's authority to register or get a service. |
| * <ul> |
| * <li>The <code>ServicePermission.REGISTER</code> action allows a bundle to |
| * register a service on the specified names. |
| * <li>The <code>ServicePermission.GET</code> action allows a bundle to |
| * detect a service and get it. |
| * </ul> |
| * Permission to get a service is required in order to detect events regarding |
| * the service. Untrusted bundles should not be able to detect the presence of |
| * certain services unless they have the appropriate |
| * <code>ServicePermission</code> to get the specific service. |
| * |
| * @version $Revision: 1.15 $ |
| */ |
| |
| final public class ServicePermission extends BasicPermission { |
| static final long serialVersionUID = -7662148639076511574L; |
| /** |
| * The action string <code>get</code> (Value is "get"). |
| */ |
| public final static String GET = "get"; |
| /** |
| * The action string <code>register</code> (Value is "register"). |
| */ |
| public final static String REGISTER = "register"; |
| |
| private final static int ACTION_GET = 0x00000001; |
| private final static int ACTION_REGISTER = 0x00000002; |
| private final static int ACTION_ALL = ACTION_GET |
| | ACTION_REGISTER; |
| private final static int ACTION_NONE = 0; |
| /** |
| * The actions mask. |
| */ |
| private transient int action_mask = ACTION_NONE; |
| |
| /** |
| * The actions in canonical form. |
| * |
| * @serial |
| */ |
| private String actions = null; |
| |
| /** |
| * Create a new ServicePermission. |
| * |
| * <p> |
| * The name of the service is specified as a fully qualified class name. |
| * |
| * <pre> |
| * ClassName ::= <class name> | <class name ending in ".*"> |
| * </pre> |
| * |
| * Examples: |
| * |
| * <pre> |
| * org.osgi.service.http.HttpService |
| * org.osgi.service.http.* |
| * org.osgi.service.snmp.* |
| * </pre> |
| * |
| * <p> |
| * There are two possible actions: <code>get</code> and |
| * <code>register</code>. The <code>get</code> permission allows the |
| * owner of this permission to obtain a service with this name. The |
| * <code>register</code> permission allows the bundle to register a |
| * service under that name. |
| * |
| * @param name class name |
| * @param actions <code>get</code>,<code>register</code> (canonical |
| * order) |
| */ |
| |
| public ServicePermission(String name, String actions) { |
| this(name, getMask(actions)); |
| } |
| |
| /** |
| * Package private constructor used by ServicePermissionCollection. |
| * |
| * @param name class name |
| * @param mask action mask |
| */ |
| ServicePermission(String name, int mask) { |
| super(name); |
| |
| init(mask); |
| } |
| |
| /** |
| * Called by constructors and when deserialized. |
| * |
| * @param mask action mask |
| */ |
| private void init(int mask) { |
| if ((mask == ACTION_NONE) || ((mask & ACTION_ALL) != mask)) { |
| throw new IllegalArgumentException("invalid action string"); |
| } |
| |
| action_mask = mask; |
| } |
| |
| /** |
| * Parse action string into 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 >= 2 && (a[i - 2] == 'g' || a[i - 2] == 'G') |
| && (a[i - 1] == 'e' || a[i - 1] == 'E') |
| && (a[i] == 't' || a[i] == 'T')) { |
| matchlen = 3; |
| mask |= ACTION_GET; |
| |
| } |
| else |
| if (i >= 7 && (a[i - 7] == 'r' || a[i - 7] == 'R') |
| && (a[i - 6] == 'e' || a[i - 6] == 'E') |
| && (a[i - 5] == 'g' || a[i - 5] == 'G') |
| && (a[i - 4] == 'i' || a[i - 4] == 'I') |
| && (a[i - 3] == 's' || a[i - 3] == 'S') |
| && (a[i - 2] == 't' || a[i - 2] == 'T') |
| && (a[i - 1] == 'e' || a[i - 1] == 'E') |
| && (a[i] == 'r' || a[i] == 'R')) { |
| matchlen = 8; |
| mask |= ACTION_REGISTER; |
| |
| } |
| else { |
| // parse error |
| throw new IllegalArgumentException("invalid permission: " |
| + actions); |
| } |
| |
| // make sure we didn't just match the tail of a word |
| // like "ackbarfregister". 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; |
| } |
| |
| /** |
| * Determines if a <code>ServicePermission</code> object "implies" the |
| * specified permission. |
| * |
| * @param p The target permission to check. |
| * @return <code>true</code> if the specified permission is implied by |
| * this object; <code>false</code> otherwise. |
| */ |
| |
| public boolean implies(Permission p) { |
| if (p instanceof ServicePermission) { |
| ServicePermission target = (ServicePermission) p; |
| |
| return (((action_mask & target.action_mask) == target.action_mask) && super |
| .implies(p)); |
| } |
| |
| return (false); |
| } |
| |
| /** |
| * Returns the canonical string representation of the actions. Always |
| * returns present actions in the following order: <code>get</code>, |
| * <code>register</code>. |
| * |
| * @return The canonical string representation of the actions. |
| */ |
| public String getActions() { |
| if (actions == null) { |
| StringBuffer sb = new StringBuffer(); |
| boolean comma = false; |
| |
| if ((action_mask & ACTION_GET) == ACTION_GET) { |
| sb.append(GET); |
| comma = true; |
| } |
| |
| if ((action_mask & ACTION_REGISTER) == ACTION_REGISTER) { |
| if (comma) |
| sb.append(','); |
| sb.append(REGISTER); |
| } |
| |
| actions = sb.toString(); |
| } |
| |
| return (actions); |
| } |
| |
| /** |
| * Returns a new <code>PermissionCollection</code> object for storing |
| * <code>ServicePermission<code> objects. |
| * |
| * @return A new <code>PermissionCollection</code> object suitable for storing |
| * <code>ServicePermission</code> objects. |
| */ |
| public PermissionCollection newPermissionCollection() { |
| return (new ServicePermissionCollection()); |
| } |
| |
| /** |
| * Determines the equalty of two ServicePermission objects. |
| * |
| * Checks that specified object has the same class name and action as this |
| * <code>ServicePermission</code>. |
| * |
| * @param obj The object to test for equality. |
| * @return true if obj is a <code>ServicePermission</code>, and has the |
| * same class name and actions as this |
| * <code>ServicePermission</code> object; <code>false</code> |
| * otherwise. |
| */ |
| public boolean equals(Object obj) { |
| if (obj == this) { |
| return (true); |
| } |
| |
| if (!(obj instanceof ServicePermission)) { |
| return (false); |
| } |
| |
| ServicePermission p = (ServicePermission) obj; |
| |
| return ((action_mask == p.action_mask) && getName().equals(p.getName())); |
| } |
| |
| /** |
| * Returns the hash code value for this object. |
| * |
| * @return Hash code value for this object. |
| */ |
| |
| public int hashCode() { |
| return (getName().hashCode() ^ getActions().hashCode()); |
| } |
| |
| /** |
| * Returns the current action mask. Used by the ServicePermissionCollection |
| * object. |
| * |
| * @return The actions mask. |
| */ |
| int getMask() { |
| return (action_mask); |
| } |
| |
| /** |
| * 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 { |
| // 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(); |
| init(getMask(actions)); |
| } |
| } |
| |
| /** |
| * Stores a set of ServicePermission permissions. |
| * |
| * @see java.security.Permission |
| * @see java.security.Permissions |
| * @see java.security.PermissionCollection |
| */ |
| |
| final class ServicePermissionCollection extends PermissionCollection { |
| static final long serialVersionUID = 662615640374640621L; |
| /** |
| * Table of permissions. |
| * |
| * @serial |
| */ |
| private Hashtable<String,Permission> permissions; |
| |
| /** |
| * Boolean saying if "*" is in the collection. |
| * |
| * @serial |
| */ |
| private boolean all_allowed; |
| |
| /** |
| * Creates an empty ServicePermissions object. |
| */ |
| |
| public ServicePermissionCollection() { |
| permissions = new Hashtable<String,Permission>(); |
| all_allowed = false; |
| } |
| |
| /** |
| * Adds a permission to the <code>ServicePermission</code> objects using |
| * the key for the hash as the name. |
| * |
| * @param permission The Permission object to add. |
| * |
| * @throws IllegalArgumentException If the permission is not a |
| * ServicePermission object. |
| * @throws SecurityException If this |
| * <code>ServicePermissionCollection</code> object has been marked |
| * read-only. |
| */ |
| |
| public void add(Permission permission) { |
| if (!(permission instanceof ServicePermission)) |
| throw new IllegalArgumentException("invalid permission: " |
| + permission); |
| if (isReadOnly()) |
| throw new SecurityException("attempt to add a Permission to a " |
| + "readonly PermissionCollection"); |
| |
| ServicePermission sp = (ServicePermission) permission; |
| String name = sp.getName(); |
| |
| ServicePermission existing = (ServicePermission) permissions.get(name); |
| |
| if (existing != null) { |
| int oldMask = existing.getMask(); |
| int newMask = sp.getMask(); |
| if (oldMask != newMask) { |
| permissions.put(name, new ServicePermission(name, oldMask |
| | newMask)); |
| } |
| } |
| else { |
| permissions.put(name, permission); |
| } |
| |
| if (!all_allowed) { |
| if (name.equals("*")) |
| all_allowed = true; |
| } |
| } |
| |
| /** |
| * Determines if a set of permissions implies the permissions expressed in |
| * <code>permission</code>. |
| * |
| * @param permission The Permission object to compare. |
| * |
| * @return <code>true</code> if <code>permission</code> is a proper |
| * subset of a permission in the set; <code>false</code> |
| * otherwise. |
| */ |
| |
| public boolean implies(Permission permission) { |
| if (!(permission instanceof ServicePermission)) |
| return (false); |
| |
| ServicePermission sp = (ServicePermission) permission; |
| ServicePermission x; |
| |
| int desired = sp.getMask(); |
| int effective = 0; |
| |
| // short circuit if the "*" Permission was added |
| if (all_allowed) { |
| x = (ServicePermission) permissions.get("*"); |
| if (x != null) { |
| effective |= x.getMask(); |
| if ((effective & desired) == desired) |
| return (true); |
| } |
| } |
| |
| // strategy: |
| // Check for full match first. Then work our way up the |
| // name looking for matches on a.b.* |
| |
| String name = sp.getName(); |
| |
| x = (ServicePermission) permissions.get(name); |
| |
| if (x != null) { |
| // we have a direct hit! |
| effective |= x.getMask(); |
| if ((effective & desired) == desired) |
| return (true); |
| } |
| |
| // work our way up the tree... |
| int last, offset; |
| |
| offset = name.length() - 1; |
| |
| while ((last = name.lastIndexOf(".", offset)) != -1) { |
| |
| name = name.substring(0, last + 1) + "*"; |
| x = (ServicePermission) permissions.get(name); |
| |
| if (x != null) { |
| effective |= x.getMask(); |
| if ((effective & desired) == desired) |
| return (true); |
| } |
| offset = last - 1; |
| } |
| |
| // we don't have to check for "*" as it was already checked |
| // at the top (all_allowed), so we just return false |
| return (false); |
| } |
| |
| /** |
| * Returns an enumeration of all the <code>ServicePermission</code> |
| * objects in the container. |
| * |
| * @return Enumeration of all the ServicePermission objects. |
| */ |
| |
| public Enumeration<Permission> elements() { |
| return (permissions.elements()); |
| } |
| } |