java/src/main/com/google/appengine/tools/development/agent/impl/BlackList.java

   1 // Copyright 2009 Google Inc. All Rights Reserved.
   2
   3 package com.google.appengine.tools.development.agent.impl;
   4
   5 import com.google.apphosting.runtime.security.WhiteList;
   6
   7 import java.io.File;
   8 import java.io.FilenameFilter;
   9 import java.io.IOException;
  10 import java.util.Collections;
  11 import java.util.Enumeration;
  12 import java.util.HashSet;
  13 import java.util.Set;
  14 import java.util.jar.JarEntry;
  15 import java.util.jar.JarFile;
  16 import java.util.logging.Level;
  17 import java.util.logging.Logger;
  18
  19 /**
  20  * The list of JRE classes that we don't support in user code.
  21  *
  22  */
  23 public class BlackList {
  24
  25   private static final Logger logger = Logger.getLogger(BlackList.class.getName());
  26
  27   private static Set<String> blackList = new HashSet<String>();
  28
  29   static {
  30     initBlackList();
  31   }
  32
  33   private static void initBlackList() {
  34
  35     Set<File> jreJars = getCurrentJreJars();
  36
  37     for (File f : jreJars) {
  38       JarFile jarFile = null;
  39       try {
  40         jarFile = new JarFile(f);
  41       } catch (IOException e) {
  42         logger.log(Level.SEVERE, "Unable to read a jre library while constructing the blacklist. " +
  43             "Security restrictions may not be entirely emulated. " + f.getAbsolutePath());
  44         continue;
  45       }
  46
  47       Enumeration<JarEntry> entries = jarFile.entries();
  48
  49       while (entries.hasMoreElements()) {
  50         JarEntry entry = entries.nextElement();
  51         String entryName = entry.getName();
  52         if (!entryName.endsWith(".class")) {
  53           continue;
  54         }
  55         String className = entryName.replace('/', '.').substring(0, entryName.length() -
  56             ".class".length());
  57         if (isBlackListed(className)) {
  58           blackList.add(className.replace('.', '/'));
  59         }
  60       }
  61     }
  62
  63     blackList = Collections.unmodifiableSet(blackList);
  64   }
  65
  66   private static boolean isBlackListed(String className) {
  67     Set<String> whiteList = WhiteList.getWhiteList();
  68     if (whiteList.contains(className)) {
  69       return false;
  70     }
  71     if (className.startsWith("com.sun.xml.internal.bind.")) {
  72       return false;
  73     }
  74     return true;
  75   }
  76
  77   /**
  78    * Returns a list of classes that are blacklisted. Unlike the WhiteList,
  79    * classes are in JVMS binary format, for example, "java/lang/String".
  80    */
  81   public static Set<String> getBlackList() {
  82     return blackList;
  83   }
  84
  85   private static Set<File> getCurrentJreJars() {
  86     return getJreJars(System.getProperty("java.home"));
  87   }
  88
  89   private static Set<File> getJreJars(String jreHome) {
  90     Set<File> matchingFiles = new HashSet<File>();
  91     FilenameFilter filter = new FilenameFilter() {
  92       @Override
  93       public boolean accept(File dir, String name) {
  94         return name.endsWith(".jar");
  95       }
  96     };
  97
  98     getFilesRecursive(matchingFiles, new File(jreHome + File.separator + "lib"), filter);
  99
 100     return matchingFiles;
 101   }
 102
 103   private static void getFilesRecursive(final Set<File> matchingFiles, final File dir,
 104       final FilenameFilter filter) {
 105     File[] files = dir.listFiles();
 106
 107     for (File f : files) {
 108       if (f.isDirectory()) {
 109         getFilesRecursive(matchingFiles, f, filter);
 110       } else if (filter.accept(dir, f.getName())) {
 111         matchingFiles.add(f);
 112       }
 113     }
 114   }
 115
 116 }