001 /* UnresolvedPermission.java -- Placeholder for unresolved permissions
002 Copyright (C) 1998, 2001, 2002, 2004, 2005 Free Software Foundation, Inc.
003
004 This file is part of GNU Classpath.
005
006 GNU Classpath is free software; you can redistribute it and/or modify
007 it under the terms of the GNU General Public License as published by
008 the Free Software Foundation; either version 2, or (at your option)
009 any later version.
010
011 GNU Classpath is distributed in the hope that it will be useful, but
012 WITHOUT ANY WARRANTY; without even the implied warranty of
013 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
014 General Public License for more details.
015
016 You should have received a copy of the GNU General Public License
017 along with GNU Classpath; see the file COPYING. If not, write to the
018 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019 02110-1301 USA.
020
021 Linking this library statically or dynamically with other modules is
022 making a combined work based on this library. Thus, the terms and
023 conditions of the GNU General Public License cover the whole
024 combination.
025
026 As a special exception, the copyright holders of this library give you
027 permission to link this library with independent modules to produce an
028 executable, regardless of the license terms of these independent
029 modules, and to copy and distribute the resulting executable under
030 terms of your choice, provided that you also meet, for each linked
031 independent module, the terms and conditions of the license of that
032 module. An independent module is a module which is not derived from
033 or based on this library. If you modify this library, you may extend
034 this exception to your version of the library, but you are not
035 obligated to do so. If you do not wish to do so, delete this
036 exception statement from your version. */
037
038
039 package java.security;
040
041 // All uses of Certificate in this file refer to the one in the listed
042 // package, not this one.
043 import java.security.cert.Certificate;
044 import java.util.Arrays;
045 import java.util.Enumeration;
046 import java.util.Hashtable;
047 import java.util.NoSuchElementException;
048 import java.util.Vector;
049
050 /**
051 * This class is used to hold instances of all permissions that cannot
052 * be resolved to available permission classes when the security
053 * <code>Policy</code> object is instantiated. This may happen when the
054 * necessary security class has not yet been downloaded from the network.
055 *
056 * <p>Instances of this class are re-resolved when
057 * <code>AccessController</code> check is done. At that time, a scan is
058 * made of all existing <code>UnresolvedPermission</code> objects and they
059 * are converted to objects of the appropriate permission type if the class
060 * for that type is then available.
061 *
062 * @author Aaron M. Renn (arenn@urbanophile.com)
063 * @see Permission
064 * @see Permissions
065 * @see PermissionCollection
066 * @see Policy
067 * @since 1.1
068 * @status updated to 1.4
069 */
070 public final class UnresolvedPermission extends Permission
071 {
072 /**
073 * Compatible with JDK 1.1+.
074 */
075 private static final long serialVersionUID = -4821973115467008846L;
076
077 /**
078 * The list of actions associated with this permission object.
079 *
080 * @serial the permission actions
081 */
082 private final String actions;
083
084 /**
085 * The list of <code>Certificates</code> associated with this object.
086 */
087 private final transient Certificate[] certs;
088
089 /**
090 * The name of the class this object should be resolved to.
091 *
092 * @serial the fully-qualified classname of the resolved type
093 */
094 // Package visible for use by UnresolvedPermissionCollection.
095 final String type;
096
097 /**
098 * The name of the permission.
099 *
100 * @serial the permission name
101 */
102 private final String name;
103
104 /**
105 * Create a new instance with all the information necessary to resolve it
106 * to an instance of the proper class at a future time.
107 *
108 * @param type the fully-qualified name of the class of this permission
109 * @param name the name of this permission
110 * @param actions the action list for this permission
111 * @param certs the list of certificates that sign this permission
112 */
113 public UnresolvedPermission(String type, String name, String actions,
114 Certificate[] certs)
115 {
116 super(name);
117 this.name = name;
118 this.type = type;
119 this.actions = actions;
120 this.certs = certs;
121 }
122
123 /**
124 * This method returns <code>false</code> always to indicate that this
125 * permission does not imply the specified permission. An
126 * <code>UnresolvedPermission</code> never grants any permissions.
127 *
128 * @param perm the <code>Permission</code> object to test
129 * @return false; until a permission is resolved, it implies nothing
130 */
131 public boolean implies(Permission perm)
132 {
133 return false;
134 }
135
136 /**
137 * This method tests this permission for equality against the specified
138 * <code>Object</code>. This will be true if and only if the following
139 * conditions are met:<ul>
140 * <li>The specified <code>Object</code> is an UnresolvedPermission</li>
141 * <li>The specified permission has the same type (i.e., desired class name)
142 * as this permission.</li>
143 * <li>The specified permission has the same name as this one.</li>
144 * <li>The specified permissoin has the same action list as this one.</li>
145 * <li>The specified permission has the same certificate list as this
146 * one.</li>
147 * </ul>
148 *
149 * @param obj the <code>Object</code> to test for equality
150 * @return true if the specified object is equal to this one
151 */
152 public boolean equals(Object obj)
153 {
154 if (! (obj instanceof UnresolvedPermission))
155 return (false);
156 UnresolvedPermission up = (UnresolvedPermission) obj;
157 return up.name.equals(name) && up.actions.equals(actions)
158 && up.type.equals(type) && Arrays.equals(up.certs, certs);
159 }
160
161 /**
162 * Returns a hash code value for this object. Following the lead of
163 * Permission, this returns the hashcode of the permission name.
164 *
165 * @return A hash value
166 */
167 public int hashCode()
168 {
169 return name.hashCode();
170 }
171
172 /**
173 * This method returns the list of actions associated with this
174 * permission.
175 *
176 * @return the action list
177 */
178 public String getActions()
179 {
180 return actions;
181 }
182
183 /**
184 * This method returns a <code>String</code> representation of this
185 * class. The format is: '(unresolved "ClassName "name" "actions")'
186 *
187 * @return <code>String</code> representation of this object
188 */
189 public String toString()
190 {
191 return "(unresolved " + type + ' ' + name + ' ' + actions + ')';
192 }
193
194 /**
195 * This class returns a <code>PermissionCollection</code> object that can
196 * be used to store instances of <code>UnresolvedPermission</code>.
197 *
198 * @return a new <code>PermissionCollection</code>
199 */
200 public PermissionCollection newPermissionCollection()
201 {
202 return new UnresolvedPermissionCollection();
203 }
204
205 /**
206 * Return the name of the class of the unresolved permission.
207 * @since 1.5
208 */
209 public String getUnresolvedType()
210 {
211 return type;
212 }
213
214 /**
215 * Return the name of the unresolved permission.
216 * @since 1.5
217 */
218 public String getUnresolvedName()
219 {
220 return name;
221 }
222
223 /**
224 * Return the actions of the unresolved permission, or null
225 * if there are no actions.
226 * @since 1.5
227 */
228 public String getUnresolvedActions()
229 {
230 return actions;
231 }
232
233 /**
234 * Return the certificates of the unresolved permission.
235 * If there are no certificates, null is returned. Otherwise,
236 * a new array is returned.
237 * @since 1.5
238 */
239 public Certificate[] getUnresolvedCerts()
240 {
241 if (certs == null)
242 return null;
243 return (Certificate[]) certs.clone();
244 }
245 } // class UnresolvedPermission
246
247 /**
248 * Implements the permission collection for unresolved permissions, and
249 * obeys serialization of JDK.
250 *
251 * @author Eric Blake (ebb9@email.byu.edu)
252 */
253 class UnresolvedPermissionCollection extends PermissionCollection
254 {
255 /**
256 * Compatible with JDK 1.1+.
257 */
258 private static final long serialVersionUID = -7176153071733132400L;
259
260 // Package-private to avoid a trampoline.
261 /**
262 * Hashtable where we store permissions.
263 *
264 * @serial map of typename to a Vector of permissions (you'd think Sun
265 * would document this better!)
266 */
267 final Hashtable permissions = new Hashtable();
268
269 /**
270 * Add a permission.
271 *
272 * @param perm the permission to add
273 * @throws IllegalArgumentException if perm is not an UnresolvedPermission
274 * @throws SecurityException if the collection is read-only
275 */
276 public void add(Permission perm)
277 {
278 if (isReadOnly())
279 throw new SecurityException();
280 if (! (perm instanceof UnresolvedPermission))
281 throw new IllegalArgumentException();
282 UnresolvedPermission up = (UnresolvedPermission) perm;
283 Vector v = (Vector) permissions.get(up.type);
284 if (v == null)
285 {
286 v = new Vector();
287 permissions.put(up.type, v);
288 }
289 v.add(up);
290 }
291
292 /**
293 * Returns true if perm is implied by the collection.
294 *
295 * @param perm the permission to check
296 * @return false; unresolved permissions imply nothing
297 */
298 public boolean implies(Permission perm)
299 {
300 return false;
301 }
302
303 /**
304 * Return the elements.
305 *
306 * @return the elements
307 */
308 public Enumeration elements()
309 {
310 return new Enumeration()
311 {
312 Enumeration main_enum = permissions.elements();
313 Enumeration sub_enum;
314
315 public boolean hasMoreElements()
316 {
317 if (sub_enum == null)
318 {
319 if (main_enum == null)
320 return false;
321 if (! main_enum.hasMoreElements())
322 {
323 main_enum = null;
324 return false;
325 }
326 Vector v = (Vector) main_enum.nextElement();
327 sub_enum = v.elements();
328 }
329 if (! sub_enum.hasMoreElements())
330 {
331 sub_enum = null;
332 return hasMoreElements();
333 }
334 return true;
335 }
336
337 public Object nextElement()
338 {
339 if (! hasMoreElements())
340 throw new NoSuchElementException();
341 return sub_enum.nextElement();
342 }
343 };
344 }
345 } // class UnresolvedPermissionCollection