1 /*
2 * Copyright (c) 1999, 2015, 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 com.sun.media.sound;
27
28 import sun.misc.ManagedLocalsThread;
29
30 import java.io.BufferedInputStream;
31 import java.io.InputStream;
32 import java.io.File;
33 import java.io.FileInputStream;
34
35 import java.util.ArrayList;
36 import java.util.Iterator;
37 import java.util.List;
38 import java.util.Properties;
39 import java.util.ServiceLoader;
40
41 import java.security.AccessController;
42 import java.security.PrivilegedAction;
43
44 import javax.sound.sampled.AudioPermission;
45
46 /** Managing security in the Java Sound implementation.
47 * This class contains all code that uses and is used by
48 * SecurityManager.doPrivileged().
49 *
50 * @author Matthias Pfisterer
51 */
52 final class JSSecurityManager {
53
54 /** Prevent instantiation.
55 */
56 private JSSecurityManager() {
57 }
58
59 /** Checks if the VM currently has a SecurityManager installed.
60 * Note that this may change over time. So the result of this method
61 * should not be cached.
62 *
63 * @return true if a SecurityManger is installed, false otherwise.
64 */
65 private static boolean hasSecurityManager() {
66 return (System.getSecurityManager() != null);
67 }
68
69
70 static void checkRecordPermission() throws SecurityException {
71 if(Printer.trace) Printer.trace("JSSecurityManager.checkRecordPermission()");
72 SecurityManager sm = System.getSecurityManager();
73 if (sm != null) {
74 sm.checkPermission(new AudioPermission("record"));
75 }
76 }
77
78 /** Load properties from a file.
79 This method tries to load properties from the filename give into
80 the passed properties object.
81 If the file cannot be found or something else goes wrong,
82 the method silently fails.
83 @param properties The properties bundle to store the values of the
84 properties file.
85 @param filename The filename of the properties file to load. This
86 filename is interpreted as relative to the subdirectory "conf" in
87 the JRE directory.
88 */
89 static void loadProperties(final Properties properties,
90 final String filename) {
91 if(hasSecurityManager()) {
92 try {
93 // invoke the privileged action using 1.2 security
94 PrivilegedAction<Void> action = new PrivilegedAction<Void>() {
95 public Void run() {
96 loadPropertiesImpl(properties, filename);
97 return null;
98 }
99 };
100 AccessController.doPrivileged(action);
101 if(Printer.debug)Printer.debug("Loaded properties with JDK 1.2 security");
102 } catch (Exception e) {
103 if(Printer.debug)Printer.debug("Exception loading properties with JDK 1.2 security");
104 // try without using JDK 1.2 security
105 loadPropertiesImpl(properties, filename);
106 }
107 } else {
108 // not JDK 1.2 security, assume we already have permission
109 loadPropertiesImpl(properties, filename);
110 }
111 }
112
113
114 private static void loadPropertiesImpl(Properties properties,
115 String filename) {
116 if(Printer.trace)Printer.trace(">> JSSecurityManager: loadPropertiesImpl()");
117 String fname = System.getProperty("java.home");
118 try {
119 if (fname == null) {
120 throw new Error("Can't find java.home ??");
121 }
122 File f = new File(fname, "conf");
123 f = new File(f, filename);
124 fname = f.getCanonicalPath();
125 InputStream in = new FileInputStream(fname);
126 BufferedInputStream bin = new BufferedInputStream(in);
127 try {
128 properties.load(bin);
129 } finally {
130 if (in != null) {
131 in.close();
132 }
133 }
134 } catch (Throwable t) {
135 if (Printer.trace) {
136 System.err.println("Could not load properties file \"" + fname + "\"");
137 t.printStackTrace();
138 }
139 }
140 if(Printer.trace)Printer.trace("<< JSSecurityManager: loadPropertiesImpl() completed");
141 }
142
143 /** Create a Thread in the current ThreadGroup.
144 */
145 static Thread createThread(final Runnable runnable,
146 final String threadName,
147 final boolean isDaemon, final int priority,
148 final boolean doStart) {
149 Thread thread = new ManagedLocalsThread(runnable);
150
151 if (threadName != null) {
152 thread.setName(threadName);
153 }
154 thread.setDaemon(isDaemon);
155 if (priority >= 0) {
156 thread.setPriority(priority);
157 }
158 if (doStart) {
159 thread.start();
160 }
161 return thread;
162 }
163
164 static synchronized <T> List<T> getProviders(final Class<T> providerClass) {
165 List<T> p = new ArrayList<>(7);
166 // ServiceLoader creates "lazy" iterator instance, but it ensures that
167 // next/hasNext run with permissions that are restricted by whatever
168 // creates the ServiceLoader instance, so it requires to be called from
169 // privileged section
170 final PrivilegedAction<Iterator<T>> psAction =
171 new PrivilegedAction<Iterator<T>>() {
172 @Override
173 public Iterator<T> run() {
174 return ServiceLoader.load(providerClass).iterator();
175 }
176 };
177 final Iterator<T> ps = AccessController.doPrivileged(psAction);
178
179 // the iterator's hasNext() method looks through classpath for
180 // the provider class names, so it requires read permissions
181 PrivilegedAction<Boolean> hasNextAction = new PrivilegedAction<Boolean>() {
182 public Boolean run() {
183 return ps.hasNext();
184 }
185 };
186
187 while (AccessController.doPrivileged(hasNextAction)) {
188 try {
189 // the iterator's next() method creates instances of the
190 // providers and it should be called in the current security
191 // context
192 T provider = ps.next();
193 if (providerClass.isInstance(provider)) {
194 // $$mp 2003-08-22
195 // Always adding at the beginning reverses the
196 // order of the providers. So we no longer have
197 // to do this in AudioSystem and MidiSystem.
198 p.add(0, provider);
199 }
200 } catch (Throwable t) {
201 //$$fb 2002-11-07: do not fail on SPI not found
202 if (Printer.err) t.printStackTrace();
203 }
204 }
205 return p;
206 }
207 }