1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one
3    * or more contributor license agreements.  See the NOTICE file
4    * distributed with this work for additional information
5    * regarding copyright ownership.  The ASF licenses this file
6    * to you under the Apache License, Version 2.0 (the
7    * "License"); you may not use this file except in compliance
8    * with the License.  You may obtain a copy of the License at
9    *
10   *    http://www.apache.org/licenses/LICENSE-2.0
11   *
12   * Unless required by applicable law or agreed to in writing,
13   * software distributed under the License is distributed on an
14   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15   * KIND, either express or implied.  See the License for the
16   * specific language governing permissions and limitations
17   * under the License.
18   */ 
19   
20  package org.apache.commons.logging.security;
21  
22  import java.io.FilePermission;
23  import java.security.Permission;
24  import java.security.Permissions;
25  
26  
27  /**
28   * Custom implementation of a security manager, so we can control the
29   * security environment for tests in this package.
30   */
31  public class MockSecurityManager extends SecurityManager {
32  
33      private Permissions permissions = new Permissions();
34      private static final Permission setSecurityManagerPerm =
35          new RuntimePermission("setSecurityManager");
36      
37      private int untrustedCodeCount = 0;
38  
39      public MockSecurityManager() {
40          permissions.add(setSecurityManagerPerm);
41      }
42  
43      /**
44       * Define the set of permissions to be granted to classes in the o.a.c.l package,
45       * but NOT to unit-test classes in o.a.c.l.security package.
46       */
47      public void addPermission(Permission p) {
48          permissions.add(p);
49      }
50  
51      /**
52       * This returns the number of times that a check of a permission failed
53       * due to stack-walking tracing up into untrusted code. Any non-zero
54       * value indicates a bug in JCL, ie a situation where code was not
55       * correctly wrapped in an AccessController block. The result of such a
56       * bug is that signing JCL is not sufficient to allow JCL to perform
57       * the operation; the caller would need to be signed too. 
58       */
59      public int getUntrustedCodeCount() {
60          return untrustedCodeCount;
61      }
62  
63      public void checkPermission(Permission p) throws SecurityException {
64          if (setSecurityManagerPerm.implies(p)) {
65              // ok, allow this; we don't want to block any calls to setSecurityManager
66              // otherwise this custom security manager cannot be reset to the original.
67              // System.out.println("setSecurityManager: granted");
68              return;
69          }
70  
71          // Allow read-only access to files, as this is needed to load classes!
72          // Ideally, we would limit this to just .class and .jar files.
73          if (p instanceof FilePermission) {
74            FilePermission fp = (FilePermission) p;
75            if (fp.getActions().equals("read")) {
76              // System.out.println("Permit read of files");
77              return;
78            }
79          }
80  
81          System.out.println("\n\ntesting permission:" + p.getClass() + ":"+ p);
82  
83          Exception e = new Exception();
84          e.fillInStackTrace();
85          StackTraceElement[] stack = e.getStackTrace();
86          
87          // scan the call stack from most recent to oldest.
88          // start at 1 to skip the entry in the stack for this method
89          for(int i=1; i<stack.length; ++i) {
90              String cname = stack[i].getClassName();
91              System.out.println("" + i + ":" + stack[i].getClassName() + 
92                "." + stack[i].getMethodName());
93  
94              if (cname.equals("java.security.AccessController")) {
95                  // Presumably method name equals "doPrivileged"
96                  //
97                  // The previous iteration of this loop verified that the
98                  // PrivilegedAction.run method associated with this
99                  // doPrivileged method call had the right permissions,
100                 // so we just return here. Effectively, the method invoking
101                 // doPrivileged asserted that it checked the input params
102                 // and found them safe, and that code is trusted, so we
103                 // don't need to check the trust level of code higher in
104                 // the call stack.
105                 System.out.println("Access controller found: returning");
106                 return;
107             } else if (cname.startsWith("java.") 
108                 || cname.startsWith("javax.") 
109                 || cname.startsWith("junit.") 
110                 || cname.startsWith("org.apache.tools.ant.")
111                 || cname.startsWith("sun.")) {
112                 // Code in these packages is trusted if the caller is trusted.
113                 //
114                 // TODO: maybe check class is loaded via system loader or similar rather
115                 // than checking name? Trusted domains may be different in alternative
116                 // jvms..
117             } else if (cname.startsWith("org.apache.commons.logging.security")) {
118                 // this is the unit test code; treat this like an untrusted client
119                 // app that is using JCL
120                 ++untrustedCodeCount;
121                 System.out.println("Untrusted code [testcase] found");
122                 throw new SecurityException("Untrusted code [testcase] found");
123             } else if (cname.startsWith("org.apache.commons.logging.")) {
124                 if (permissions.implies(p)) {
125                     // Code here is trusted if the caller is trusted
126                     System.out.println("Permission in allowed set for JCL class");
127                 } else {
128                     System.out.println("Permission refused:" + p.getClass() + ":" + p);
129                     throw new SecurityException("Permission refused:" + p.getClass() + ":" + p);
130                 }
131             } else {
132                 // we found some code that is not trusted to perform this operation.
133                 System.out.println("Unexpected code: permission refused:" + p.getClass() + ":" + p);
134                 throw new SecurityException("Unexpected code: permission refused:" + p.getClass() + ":" + p);
135             }
136         }
137     }
138 }