1 /* 2 * Copyright (c) 2019, 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.security.util; 27 28 import java.io.File; 29 import java.io.FilePermission; 30 import java.io.IOException; 31 import java.net.URL; 32 import java.security.CodeSource; 33 import java.security.Permission; 34 import java.security.PermissionCollection; 35 import java.util.Enumeration; 36 37 /** 38 * This {@code PermissionCollection} implementation delegates to another 39 * {@code PermissionCollection}, taking care to lazily add the permission needed 40 * to read from the given {@code CodeSource} at first use, i.e., when either of 41 * {@link #elements}, {@link #implies} or {@link #toString} is called, or when 42 * the collection is serialized. 43 */ 44 public final class LazyCodeSourcePermissionCollection 45 extends PermissionCollection 46 { 47 private static final long serialVersionUID = -6727011328946861783L; 48 private final PermissionCollection perms; 49 private final CodeSource cs; 50 private volatile boolean permissionAdded; 51 52 public LazyCodeSourcePermissionCollection(PermissionCollection perms, 53 CodeSource cs) { 54 this.perms = perms; 55 this.cs = cs; 56 } 57 58 private void ensureAdded() { 59 if (!permissionAdded) { 60 synchronized(perms) { 61 if (permissionAdded) 62 return; 63 64 // open connection to determine the permission needed 65 URL location = cs.getLocation(); 66 if (location != null) { 67 try { 68 Permission p = location.openConnection().getPermission(); 69 if (p != null) { 70 // for directories then need recursive access 71 if (p instanceof FilePermission) { 72 String path = p.getName(); 73 if (path.endsWith(File.separator)) { 74 path += "-"; 75 p = new FilePermission(path, 76 SecurityConstants.FILE_READ_ACTION); 77 } 78 } 79 perms.add(p); 80 } 81 } catch (IOException ioe) { 82 } 83 } 84 if (isReadOnly()) { 85 perms.setReadOnly(); 86 } 87 permissionAdded = true; 88 } 89 } 90 } 91 92 @Override 93 public void add(Permission permission) { 94 if (isReadOnly()) 95 throw new SecurityException( 96 "attempt to add a Permission to a readonly PermissionCollection"); 97 perms.add(permission); 98 } 99 100 @Override 101 public boolean implies(Permission permission) { 102 ensureAdded(); 103 return perms.implies(permission); 104 } 105 106 @Override 107 public Enumeration<Permission> elements() { 108 ensureAdded(); 109 return perms.elements(); 110 } 111 112 @Override 113 public String toString() { 114 ensureAdded(); 115 return perms.toString(); 116 } 117 118 /** 119 * On serialization, initialize and replace with the underlying 120 * permissions. This removes the laziness on deserialization. 121 */ 122 private Object writeReplace() { 123 ensureAdded(); 124 return perms; 125 } 126 }