1 /*
   2  * Copyright (c) 1998, 2011, 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.misc;
  27 
  28 import java.io.File;
  29 import java.io.IOException;
  30 import java.io.FilePermission;
  31 import java.net.URL;
  32 import java.net.URLClassLoader;
  33 import java.net.MalformedURLException;
  34 import java.net.URLStreamHandler;
  35 import java.net.URLStreamHandlerFactory;
  36 import java.util.HashSet;
  37 import java.util.StringTokenizer;
  38 import java.util.Set;
  39 import java.util.Vector;
  40 import java.security.AccessController;
  41 import java.security.PrivilegedAction;
  42 import java.security.PrivilegedExceptionAction;
  43 import java.security.AccessControlContext;
  44 import java.security.PermissionCollection;
  45 import java.security.Permissions;
  46 import java.security.Permission;
  47 import java.security.ProtectionDomain;
  48 import java.security.CodeSource;
  49 import sun.security.util.SecurityConstants;
  50 import sun.net.www.ParseUtil;
  51 
  52 /**
  53  * This class is used by the system to launch the main application.
  54 Launcher */
  55 public class Launcher {
  56     private static URLStreamHandlerFactory factory = new Factory();
  57     private static Launcher launcher = new Launcher();
  58     private static String bootClassPath =
  59         System.getProperty("sun.boot.class.path");
  60 
  61     public static Launcher getLauncher() {
  62         return launcher;
  63     }
  64 
  65     private ClassLoader loader;
  66 
  67     public Launcher() {
  68         // Create the extension class loader
  69         ClassLoader extcl;
  70         try {
  71             extcl = ExtClassLoader.getExtClassLoader();
  72         } catch (IOException e) {
  73             throw new InternalError(
  74                 "Could not create extension class loader", e);
  75         }
  76 
  77         // Now create the class loader to use to launch the application
  78         try {
  79             loader = AppClassLoader.getAppClassLoader(extcl);
  80         } catch (IOException e) {
  81             throw new InternalError(
  82                 "Could not create application class loader", e);
  83         }
  84 
  85         // Also set the context class loader for the primordial thread.
  86         Thread.currentThread().setContextClassLoader(loader);
  87 
  88         // Finally, install a security manager if requested
  89         String s = System.getProperty("java.security.manager");
  90         if (s != null) {
  91             SecurityManager sm = null;
  92             if ("".equals(s) || "default".equals(s)) {
  93                 sm = new java.lang.SecurityManager();
  94             } else {
  95                 try {
  96                     sm = (SecurityManager)loader.loadClass(s).newInstance();
  97                 } catch (IllegalAccessException e) {
  98                 } catch (InstantiationException e) {
  99                 } catch (ClassNotFoundException e) {
 100                 } catch (ClassCastException e) {
 101                 }
 102             }
 103             if (sm != null) {
 104                 System.setSecurityManager(sm);
 105             } else {
 106                 throw new InternalError(
 107                     "Could not create SecurityManager: " + s);
 108             }
 109         }
 110     }
 111 
 112     /*
 113      * Returns the class loader used to launch the main application.
 114      */
 115     public ClassLoader getClassLoader() {
 116         return loader;
 117     }
 118 
 119     /*
 120      * The class loader used for loading installed extensions.
 121      */
 122     static class ExtClassLoader extends URLClassLoader {
 123 
 124         static {
 125             ClassLoader.registerAsParallelCapable();
 126         }
 127 
 128         /**
 129          * create an ExtClassLoader. The ExtClassLoader is created
 130          * within a context that limits which files it can read
 131          */
 132         public static ExtClassLoader getExtClassLoader() throws IOException
 133         {
 134             final File[] dirs = getExtDirs();
 135 
 136             try {
 137                 // Prior implementations of this doPrivileged() block supplied
 138                 // aa synthesized ACC via a call to the private method
 139                 // ExtClassLoader.getContext().
 140 
 141                 return AccessController.doPrivileged(
 142                     new PrivilegedExceptionAction<ExtClassLoader>() {
 143                         public ExtClassLoader run() throws IOException {
 144                             int len = dirs.length;
 145                             for (int i = 0; i < len; i++) {
 146                                 MetaIndex.registerDirectory(dirs[i]);
 147                             }
 148                             return new ExtClassLoader(dirs);
 149                         }
 150                     });
 151             } catch (java.security.PrivilegedActionException e) {
 152                 throw (IOException) e.getException();
 153             }
 154         }
 155 
 156         void addExtURL(URL url) {
 157             super.addURL(url);
 158         }
 159 
 160         /*
 161          * Creates a new ExtClassLoader for the specified directories.
 162          */
 163         public ExtClassLoader(File[] dirs) throws IOException {
 164             super(getExtURLs(dirs), null, factory);
 165         }
 166 
 167         private static File[] getExtDirs() {
 168             String s = System.getProperty("java.ext.dirs");
 169             File[] dirs;
 170             if (s != null) {
 171                 StringTokenizer st =
 172                     new StringTokenizer(s, File.pathSeparator);
 173                 int count = st.countTokens();
 174                 dirs = new File[count];
 175                 for (int i = 0; i < count; i++) {
 176                     dirs[i] = new File(st.nextToken());
 177                 }
 178             } else {
 179                 dirs = new File[0];
 180             }
 181             return dirs;
 182         }
 183 
 184         private static URL[] getExtURLs(File[] dirs) throws IOException {
 185             Vector<URL> urls = new Vector<URL>();
 186             for (int i = 0; i < dirs.length; i++) {
 187                 String[] files = dirs[i].list();
 188                 if (files != null) {
 189                     for (int j = 0; j < files.length; j++) {
 190                         if (!files[j].equals("meta-index")) {
 191                             File f = new File(dirs[i], files[j]);
 192                             urls.add(getFileURL(f));
 193                         }
 194                     }
 195                 }
 196             }
 197             URL[] ua = new URL[urls.size()];
 198             urls.copyInto(ua);
 199             return ua;
 200         }
 201 
 202         /*
 203          * Searches the installed extension directories for the specified
 204          * library name. For each extension directory, we first look for
 205          * the native library in the subdirectory whose name is the value
 206          * of the system property <code>os.arch</code>. Failing that, we
 207          * look in the extension directory itself.
 208          */
 209         public String findLibrary(String name) {
 210             name = System.mapLibraryName(name);
 211             URL[] urls = super.getURLs();
 212             File prevDir = null;
 213             for (int i = 0; i < urls.length; i++) {
 214                 // Get the ext directory from the URL
 215                 File dir = new File(urls[i].getPath()).getParentFile();
 216                 if (dir != null && !dir.equals(prevDir)) {
 217                     // Look in architecture-specific subdirectory first
 218                     // Read from the saved system properties to avoid deadlock
 219                     String arch = VM.getSavedProperty("os.arch");
 220                     if (arch != null) {
 221                         File file = new File(new File(dir, arch), name);
 222                         if (file.exists()) {
 223                             return file.getAbsolutePath();
 224                         }
 225                     }
 226                     // Then check the extension directory
 227                     File file = new File(dir, name);
 228                     if (file.exists()) {
 229                         return file.getAbsolutePath();
 230                     }
 231                 }
 232                 prevDir = dir;
 233             }
 234             return null;
 235         }
 236 
 237         private static AccessControlContext getContext(File[] dirs)
 238             throws IOException
 239         {
 240             PathPermissions perms =
 241                 new PathPermissions(dirs);
 242 
 243             ProtectionDomain domain = new ProtectionDomain(
 244                 new CodeSource(perms.getCodeBase(),
 245                     (java.security.cert.Certificate[]) null),
 246                 perms);
 247 
 248             AccessControlContext acc =
 249                 new AccessControlContext(new ProtectionDomain[] { domain });
 250 
 251             return acc;
 252         }
 253     }
 254 
 255     /**
 256      * The class loader used for loading from java.class.path.
 257      * runs in a restricted security context.
 258      */
 259     static class AppClassLoader extends URLClassLoader {
 260 
 261         static {
 262             ClassLoader.registerAsParallelCapable();
 263         }
 264 
 265         public static ClassLoader getAppClassLoader(final ClassLoader extcl)
 266             throws IOException
 267         {
 268             final String s = System.getProperty("java.class.path");
 269             final File[] path = (s == null) ? new File[0] : getClassPath(s);
 270 
 271             // Note: on bugid 4256530
 272             // Prior implementations of this doPrivileged() block supplied
 273             // a rather restrictive ACC via a call to the private method
 274             // AppClassLoader.getContext(). This proved overly restrictive
 275             // when loading  classes. Specifically it prevent
 276             // accessClassInPackage.sun.* grants from being honored.
 277             //
 278             return AccessController.doPrivileged(
 279                 new PrivilegedAction<AppClassLoader>() {
 280                     public AppClassLoader run() {
 281                     URL[] urls =
 282                         (s == null) ? new URL[0] : pathToURLs(path);
 283                     return new AppClassLoader(urls, extcl);
 284                 }
 285             });
 286         }
 287 
 288         /*
 289          * Creates a new AppClassLoader
 290          */
 291         AppClassLoader(URL[] urls, ClassLoader parent) {
 292             super(urls, parent, factory);
 293         }
 294 
 295         /**
 296          * Override loadClass so we can checkPackageAccess.
 297          */
 298         public Class loadClass(String name, boolean resolve)
 299             throws ClassNotFoundException
 300         {
 301             int i = name.lastIndexOf('.');
 302             if (i != -1) {
 303                 SecurityManager sm = System.getSecurityManager();
 304                 if (sm != null) {
 305                     sm.checkPackageAccess(name.substring(0, i));
 306                 }
 307             }
 308             return (super.loadClass(name, resolve));
 309         }
 310 
 311         /**
 312          * allow any classes loaded from classpath to exit the VM.
 313          */
 314         protected PermissionCollection getPermissions(CodeSource codesource)
 315         {
 316             PermissionCollection perms = super.getPermissions(codesource);
 317             perms.add(new RuntimePermission("exitVM"));
 318             return perms;
 319         }
 320 
 321         /**
 322          * This class loader supports dynamic additions to the class path
 323          * at runtime.
 324          *
 325          * @see java.lang.instrument.Instrumentation#appendToSystemClassPathSearch
 326          */
 327         private void appendToClassPathForInstrumentation(String path) {
 328             assert(Thread.holdsLock(this));
 329 
 330             // addURL is a no-op if path already contains the URL
 331             super.addURL( getFileURL(new File(path)) );
 332         }
 333 
 334         /**
 335          * create a context that can read any directories (recursively)
 336          * mentioned in the class path. In the case of a jar, it has to
 337          * be the directory containing the jar, not just the jar, as jar
 338          * files might refer to other jar files.
 339          */
 340 
 341         private static AccessControlContext getContext(File[] cp)
 342             throws java.net.MalformedURLException
 343         {
 344             PathPermissions perms =
 345                 new PathPermissions(cp);
 346 
 347             ProtectionDomain domain =
 348                 new ProtectionDomain(new CodeSource(perms.getCodeBase(),
 349                     (java.security.cert.Certificate[]) null),
 350                 perms);
 351 
 352             AccessControlContext acc =
 353                 new AccessControlContext(new ProtectionDomain[] { domain });
 354 
 355             return acc;
 356         }
 357     }
 358 
 359     private static class BootClassPathHolder {
 360         static final URLClassPath bcp;
 361         static {
 362             URL[] urls;
 363             if (bootClassPath != null) {
 364                 urls = AccessController.doPrivileged(
 365                     new PrivilegedAction<URL[]>() {
 366                         public URL[] run() {
 367                             File[] classPath = getClassPath(bootClassPath);
 368                             int len = classPath.length;
 369                             Set<File> seenDirs = new HashSet<File>();
 370                             for (int i = 0; i < len; i++) {
 371                                 File curEntry = classPath[i];
 372                                 // Negative test used to properly handle
 373                                 // nonexistent jars on boot class path
 374                                 if (!curEntry.isDirectory()) {
 375                                     curEntry = curEntry.getParentFile();
 376                                 }
 377                                 if (curEntry != null && seenDirs.add(curEntry)) {
 378                                     MetaIndex.registerDirectory(curEntry);
 379                                 }
 380                             }
 381                             return pathToURLs(classPath);
 382                         }
 383                     }
 384                 );
 385             } else {
 386                 urls = new URL[0];
 387             }
 388             bcp = new URLClassPath(urls, factory);
 389         }
 390     }
 391 
 392     public static URLClassPath getBootstrapClassPath() {
 393         return BootClassPathHolder.bcp;
 394     }
 395 
 396     private static URL[] pathToURLs(File[] path) {
 397         URL[] urls = new URL[path.length];
 398         for (int i = 0; i < path.length; i++) {
 399             urls[i] = getFileURL(path[i]);
 400         }
 401         // DEBUG
 402         //for (int i = 0; i < urls.length; i++) {
 403         //  System.out.println("urls[" + i + "] = " + '"' + urls[i] + '"');
 404         //}
 405         return urls;
 406     }
 407 
 408     private static File[] getClassPath(String cp) {
 409         File[] path;
 410         if (cp != null) {
 411             int count = 0, maxCount = 1;
 412             int pos = 0, lastPos = 0;
 413             // Count the number of separators first
 414             while ((pos = cp.indexOf(File.pathSeparator, lastPos)) != -1) {
 415                 maxCount++;
 416                 lastPos = pos + 1;
 417             }
 418             path = new File[maxCount];
 419             lastPos = pos = 0;
 420             // Now scan for each path component
 421             while ((pos = cp.indexOf(File.pathSeparator, lastPos)) != -1) {
 422                 if (pos - lastPos > 0) {
 423                     path[count++] = new File(cp.substring(lastPos, pos));
 424                 } else {
 425                     // empty path component translates to "."
 426                     path[count++] = new File(".");
 427                 }
 428                 lastPos = pos + 1;
 429             }
 430             // Make sure we include the last path component
 431             if (lastPos < cp.length()) {
 432                 path[count++] = new File(cp.substring(lastPos));
 433             } else {
 434                 path[count++] = new File(".");
 435             }
 436             // Trim array to correct size
 437             if (count != maxCount) {
 438                 File[] tmp = new File[count];
 439                 System.arraycopy(path, 0, tmp, 0, count);
 440                 path = tmp;
 441             }
 442         } else {
 443             path = new File[0];
 444         }
 445         // DEBUG
 446         //for (int i = 0; i < path.length; i++) {
 447         //  System.out.println("path[" + i + "] = " + '"' + path[i] + '"');
 448         //}
 449         return path;
 450     }
 451 
 452     private static URLStreamHandler fileHandler;
 453 
 454     static URL getFileURL(File file) {
 455         try {
 456             file = file.getCanonicalFile();
 457         } catch (IOException e) {}
 458 
 459         try {
 460             return ParseUtil.fileToEncodedURL(file);
 461         } catch (MalformedURLException e) {
 462             // Should never happen since we specify the protocol...
 463             throw new InternalError(e);
 464         }
 465     }
 466 
 467     /*
 468      * The stream handler factory for loading system protocol handlers.
 469      */
 470     private static class Factory implements URLStreamHandlerFactory {
 471         private static String PREFIX = "sun.net.www.protocol";
 472 
 473         public URLStreamHandler createURLStreamHandler(String protocol) {
 474             String name = PREFIX + "." + protocol + ".Handler";
 475             try {
 476                 Class c = Class.forName(name);
 477                 return (URLStreamHandler)c.newInstance();
 478             } catch (ReflectiveOperationException e) {
 479                 throw new InternalError("could not load " + protocol +
 480                                         "system protocol handler", e);
 481             }
 482         }
 483     }
 484 }
 485 
 486 class PathPermissions extends PermissionCollection {
 487     // use serialVersionUID from JDK 1.2.2 for interoperability
 488     private static final long serialVersionUID = 8133287259134945693L;
 489 
 490     private File path[];
 491     private Permissions perms;
 492 
 493     URL codeBase;
 494 
 495     PathPermissions(File path[])
 496     {
 497         this.path = path;
 498         this.perms = null;
 499         this.codeBase = null;
 500     }
 501 
 502     URL getCodeBase()
 503     {
 504         return codeBase;
 505     }
 506 
 507     public void add(java.security.Permission permission) {
 508         throw new SecurityException("attempt to add a permission");
 509     }
 510 
 511     private synchronized void init()
 512     {
 513         if (perms != null)
 514             return;
 515 
 516         perms = new Permissions();
 517 
 518         // this is needed to be able to create the classloader itself!
 519         perms.add(SecurityConstants.CREATE_CLASSLOADER_PERMISSION);
 520 
 521         // add permission to read any "java.*" property
 522         perms.add(new java.util.PropertyPermission("java.*",
 523             SecurityConstants.PROPERTY_READ_ACTION));
 524 
 525         AccessController.doPrivileged(new PrivilegedAction<Void>() {
 526             public Void run() {
 527                 for (int i=0; i < path.length; i++) {
 528                     File f = path[i];
 529                     String path;
 530                     try {
 531                         path = f.getCanonicalPath();
 532                     } catch (IOException ioe) {
 533                         path = f.getAbsolutePath();
 534                     }
 535                     if (i == 0) {
 536                         codeBase = Launcher.getFileURL(new File(path));
 537                     }
 538                     if (f.isDirectory()) {
 539                         if (path.endsWith(File.separator)) {
 540                             perms.add(new FilePermission(path+"-",
 541                                 SecurityConstants.FILE_READ_ACTION));
 542                         } else {
 543                             perms.add(new FilePermission(
 544                                 path + File.separator+"-",
 545                                 SecurityConstants.FILE_READ_ACTION));
 546                         }
 547                     } else {
 548                         int endIndex = path.lastIndexOf(File.separatorChar);
 549                         if (endIndex != -1) {
 550                             path = path.substring(0, endIndex+1) + "-";
 551                             perms.add(new FilePermission(path,
 552                                 SecurityConstants.FILE_READ_ACTION));
 553                         } else {
 554                             // XXX?
 555                         }
 556                     }
 557                 }
 558                 return null;
 559             }
 560         });
 561     }
 562 
 563     public boolean implies(java.security.Permission permission) {
 564         if (perms == null)
 565             init();
 566         return perms.implies(permission);
 567     }
 568 
 569     public java.util.Enumeration<Permission> elements() {
 570         if (perms == null)
 571             init();
 572         synchronized (perms) {
 573             return perms.elements();
 574         }
 575     }
 576 
 577     public String toString() {
 578         if (perms == null)
 579             init();
 580         return perms.toString();
 581     }
 582 }