1 /*

     2  * Copyright (c) 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 sun.security.util;

    27 

    28 import java.security.AccessController;

    29 import java.security.AlgorithmConstraints;

    30 import java.security.PrivilegedAction;

    31 import java.security.Security;

    32 import java.util.Map;

    33 import java.util.Set;

    34 

    35 /**

    36  * The class contains common functionality for algorithm constraints classes.

    37  */

    38 public abstract class AbstractAlgorithmConstraints

    39         implements AlgorithmConstraints {

    40 

    41     protected final AlgorithmDecomposer decomposer;

    42 

    43     protected AbstractAlgorithmConstraints(AlgorithmDecomposer decomposer) {

    44         this.decomposer = decomposer;

    45     }

    46 

    47     // Get algorithm constraints from the specified security property.

    48     private static void loadAlgorithmsMap(Map<String, String[]> algorithmsMap,

    49             String propertyName) {

    50         String property = AccessController.doPrivileged(

    51                 (PrivilegedAction<String>) () -> Security.getProperty(

    52                         propertyName));

    53 

    54         String[] algorithmsInProperty = null;

    55         if (property != null && !property.isEmpty()) {

    56             // remove double quote marks from beginning/end of the property

    57             if (property.charAt(0) == '"'

    58                     && property.charAt(property.length() - 1) == '"') {

    59                 property = property.substring(1, property.length() - 1);

    60             }

    61             algorithmsInProperty = property.split(",");

    62             for (int i = 0; i < algorithmsInProperty.length;

    63                     i++) {

    64                 algorithmsInProperty[i] = algorithmsInProperty[i].trim();

    65             }

    66         }

    67 

    68         // map the disabled algorithms

    69         if (algorithmsInProperty == null) {

    70             algorithmsInProperty = new String[0];

    71         }

    72         algorithmsMap.put(propertyName, algorithmsInProperty);

    73     }

    74 

    75     static String[] getAlgorithms(Map<String, String[]> algorithmsMap,

    76             String propertyName) {

    77         synchronized (algorithmsMap) {

    78             if (!algorithmsMap.containsKey(propertyName)) {

    79                 loadAlgorithmsMap(algorithmsMap, propertyName);

    80             }

    81 

    82             return algorithmsMap.get(propertyName);

    83         }

    84     }

    85 

    86     static boolean checkAlgorithm(String[] algorithms, String algorithm,

    87             AlgorithmDecomposer decomposer) {

    88         if (algorithm == null || algorithm.length() == 0) {

    89             throw new IllegalArgumentException("No algorithm name specified");

    90         }

    91 

    92         Set<String> elements = null;

    93         for (String item : algorithms) {

    94             if (item == null || item.isEmpty()) {

    95                 continue;

    96             }

    97 

    98             // check the full name

    99             if (item.equalsIgnoreCase(algorithm)) {

   100                 return false;

   101             }

   102 

   103             // decompose the algorithm into sub-elements

   104             if (elements == null) {

   105                 elements = decomposer.decompose(algorithm);

   106             }

   107 

   108             // check the items of the algorithm

   109             for (String element : elements) {

   110                 if (item.equalsIgnoreCase(element)) {

   111                     return false;

   112                 }

   113             }

   114         }

   115 

   116         return true;

   117     }

   118 

   119 }