1 /*
2 * Copyright (c) 1996, 2008, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package sun.rmi.server;
27
28 import java.io.IOException;
29 import java.io.InputStream;
30 import java.io.ObjectInputStream;
31 import java.io.ObjectStreamClass;
32 import java.io.StreamCorruptedException;
33 import java.net.URL;
34 import java.util.*;
35 import java.security.AccessControlException;
36 import java.security.Permission;
37
38 import java.rmi.server.RMIClassLoader;
39
40 /**
41 * MarshalInputStream is an extension of ObjectInputStream. When resolving
42 * a class, it reads an object from the stream written by a corresponding
43 * MarshalOutputStream. If the class to be resolved is not available
44 * locally, from the first class loader on the execution stack, or from the
45 * context class loader of the current thread, it will attempt to load the
46 * class from the location annotated by the sending MarshalOutputStream.
47 * This location object must be a string representing a path of URLs.
48 *
49 * A new MarshalInputStream should be created to deserialize remote objects or
50 * graphs containing remote objects. Objects are created from the stream
51 * using the ObjectInputStream.readObject method.
52 *
53 * @author Peter Jones
54 */
55 public class MarshalInputStream extends ObjectInputStream {
56
57 /**
58 * value of "java.rmi.server.useCodebaseOnly" property,
59 * as cached at class initialization time.
60 */
61 private static final boolean useCodebaseOnlyProperty =
62 java.security.AccessController.doPrivileged(
63 new sun.security.action.GetBooleanAction(
64 "java.rmi.server.useCodebaseOnly")).booleanValue();
65
66 /** table to hold sun classes to which access is explicitly permitted */
67 protected static Map<String, Class<?>> permittedSunClasses
68 = new HashMap<String, Class<?>>(3);
69
70 /** if true, don't try superclass first in resolveClass() */
71 private boolean skipDefaultResolveClass = false;
72
73 /** callbacks to make when done() called: maps Object to Runnable */
74 private final Map<Object, Runnable> doneCallbacks
75 = new HashMap<Object, Runnable>(3);
76
77 /**
78 * if true, load classes (if not available locally) only from the
79 * URL specified by the "java.rmi.server.codebase" property.
80 */
81 private boolean useCodebaseOnly = useCodebaseOnlyProperty;
82
83 /*
84 * Fix for 4179055: The remote object services inside the
85 * activation daemon use stubs that are in the package
86 * sun.rmi.server. Classes for these stubs should be loaded from
87 * the classpath by RMI system code and not by the normal
88 * unmarshalling process as applications should not need to have
89 * permission to access the sun implementation classes.
90 *
91 * Note: this fix should be redone when API changes may be
92 * integrated
93 *
94 * During parameter unmarshalling RMI needs to explicitly permit
95 * access to three sun.* stub classes
96 */
97 static {
98 try {
99 String system =
100 "sun.rmi.server.Activation$ActivationSystemImpl_Stub";
101 String registry = "sun.rmi.registry.RegistryImpl_Stub";
102
103 permittedSunClasses.put(system, Class.forName(system));
104 permittedSunClasses.put(registry, Class.forName(registry));
105
106 } catch (ClassNotFoundException e) {
107 throw new NoClassDefFoundError("Missing system class: " +
108 e.getMessage());
109 }
110 }
111
112 /**
113 * Create a new MarshalInputStream object.
114 */
115 public MarshalInputStream(InputStream in)
116 throws IOException, StreamCorruptedException
117 {
118 super(in);
119 }
120
121 /**
122 * Returns a callback previously registered via the setDoneCallback
123 * method with given key, or null if no callback has yet been registered
124 * with that key.
125 */
126 public Runnable getDoneCallback(Object key) {
127 return doneCallbacks.get(key); // not thread-safe
128 }
129
130 /**
131 * Registers a callback to make when this stream's done() method is
132 * invoked, along with a key for retrieving the same callback instance
133 * subsequently from the getDoneCallback method.
134 */
135 public void setDoneCallback(Object key, Runnable callback) {
136 //assert(!doneCallbacks.contains(key));
137 doneCallbacks.put(key, callback); // not thread-safe
138 }
139
140 /**
141 * Indicates that the user of this MarshalInputStream is done reading
142 * objects from it, so all callbacks registered with the setDoneCallback
143 * method should now be (synchronously) executed. When this method
144 * returns, there are no more callbacks registered.
145 *
146 * This method is implicitly invoked by close() before it delegates to
147 * the superclass's close method.
148 */
149 public void done() {
150 Iterator<Runnable> iter = doneCallbacks.values().iterator();
151 while (iter.hasNext()) { // not thread-safe
152 Runnable callback = iter.next();
153 callback.run();
154 }
155 doneCallbacks.clear();
156 }
157
158 /**
159 * Closes this stream, implicitly invoking done() first.
160 */
161 public void close() throws IOException {
162 done();
163 super.close();
164 }
165
166 /**
167 * resolveClass is extended to acquire (if present) the location
168 * from which to load the specified class.
169 * It will find, load, and return the class.
170 */
171 protected Class resolveClass(ObjectStreamClass classDesc)
172 throws IOException, ClassNotFoundException
173 {
174 /*
175 * Always read annotation written by MarshalOutputStream
176 * describing where to load class from.
177 */
178 Object annotation = readLocation();
179
180 String className = classDesc.getName();
181
182 /*
183 * Unless we were told to skip this consideration, choose the
184 * "default loader" to simulate the default ObjectInputStream
185 * resolveClass mechanism (that is, choose the first non-null
186 * loader on the execution stack) to maximize the likelihood of
187 * type compatibility with calling code. (This consideration
188 * is skipped during server parameter unmarshalling using the 1.2
189 * stub protocol, because there would never be a non-null class
190 * loader on the stack in that situation anyway.)
191 */
192 ClassLoader defaultLoader =
193 skipDefaultResolveClass ? null : latestUserDefinedLoader();
194
195 /*
196 * If the "java.rmi.server.useCodebaseOnly" property was true or
197 * useCodebaseOnly() was called or the annotation is not a String,
198 * load from the local loader using the "java.rmi.server.codebase"
199 * URL. Otherwise, load from a loader using the codebase URL in
200 * the annotation.
201 */
202 String codebase = null;
203 if (!useCodebaseOnly && annotation instanceof String) {
204 codebase = (String) annotation;
205 }
206
207 try {
208 return RMIClassLoader.loadClass(codebase, className,
209 defaultLoader);
210 } catch (AccessControlException e) {
211 return checkSunClass(className, e);
212 } catch (ClassNotFoundException e) {
213 /*
214 * Fix for 4442373: delegate to ObjectInputStream.resolveClass()
215 * to resolve primitive classes.
216 */
217 try {
218 if (Character.isLowerCase(className.charAt(0)) &&
219 className.indexOf('.') == -1)
220 {
221 return super.resolveClass(classDesc);
222 }
223 } catch (ClassNotFoundException e2) {
224 }
225 throw e;
226 }
227 }
228
229 /**
230 * resolveProxyClass is extended to acquire (if present) the location
231 * to determine the class loader to define the proxy class in.
232 */
233 protected Class resolveProxyClass(String[] interfaces)
234 throws IOException, ClassNotFoundException
235 {
236 /*
237 * Always read annotation written by MarshalOutputStream.
238 */
239 Object annotation = readLocation();
240
241 ClassLoader defaultLoader =
242 skipDefaultResolveClass ? null : latestUserDefinedLoader();
243
244 String codebase = null;
245 if (!useCodebaseOnly && annotation instanceof String) {
246 codebase = (String) annotation;
247 }
248
249 return RMIClassLoader.loadProxyClass(codebase, interfaces,
250 defaultLoader);
251 }
252
253 /*
254 * Returns the first non-null class loader up the execution stack, or null
255 * if only code from the null class loader is on the stack.
256 */
257 private static ClassLoader latestUserDefinedLoader() {
258 return sun.misc.VM.latestUserDefinedLoader();
259 }
260
261 /**
262 * Fix for 4179055: Need to assist resolving sun stubs; resolve
263 * class locally if it is a "permitted" sun class
264 */
265 private Class checkSunClass(String className, AccessControlException e)
266 throws AccessControlException
267 {
268 // ensure that we are giving out a stub for the correct reason
269 Permission perm = e.getPermission();
270 String name = null;
271 if (perm != null) {
272 name = perm.getName();
273 }
274
275 Class<?> resolvedClass = permittedSunClasses.get(className);
276
277 // if class not permitted, throw the SecurityException
278 if ((name == null) ||
279 (resolvedClass == null) ||
280 ((!name.equals("accessClassInPackage.sun.rmi.server")) &&
281 (!name.equals("accessClassInPackage.sun.rmi.registry"))))
282 {
283 throw e;
284 }
285
286 return resolvedClass;
287 }
288
289 /**
290 * Return the location for the class in the stream. This method can
291 * be overridden by subclasses that store this annotation somewhere
292 * else than as the next object in the stream, as is done by this class.
293 */
294 protected Object readLocation()
295 throws IOException, ClassNotFoundException
296 {
297 return readObject();
298 }
299
300 /**
301 * Set a flag to indicate that the superclass's default resolveClass()
302 * implementation should not be invoked by our resolveClass().
303 */
304 void skipDefaultResolveClass() {
305 skipDefaultResolveClass = true;
306 }
307
308 /**
309 * Disable code downloading except from the URL specified by the
310 * "java.rmi.server.codebase" property.
311 */
312 void useCodebaseOnly() {
313 useCodebaseOnly = true;
314 }
315 }